Media centre

Fact sheet N°392
June 2015

Key facts

  • In 2015, 68% of the world’s population had access to improved sanitation facilities including flush toilets and covered latrines, compared with 54% in 1990.
  • Nearly one third of the current global population has gained access to an improved sanitation facility since 1990, a total of 2.1 billion people.2.4 billion people still do not have basic sanitation facilities such as toilets or latrines.

Hygienic sanitation facilities are crucial for public health. Since 1990, the number of people gaining access to improved sanitation has risen from 54% to 68% but some 2.4 billion people still do not have toilets or covered latrines.

In 2010, the UN General Assembly recognized access to safe and clean drinking-water and sanitation as a human right, and called for international efforts to help countries to provide safe, clean, accessible and affordable drinking-water and sanitation.

Despite progress, the 2015 Millennium Development Goal target to halve the proportion of the population without access to improved sanitation facilities was missed by almost 700 million people.

Sanitation facilities

Despite big improvements, inequalities between and within countries and regions persist. In Southern Asia, 47% of the population was using improved sanitation facilities in 2015 compared with 22% in 1990. Sub-Saharan Africa has made slower progress, with sanitation coverage rising from 24% to 30% in 2015. In 47 countries, less than half the population has access to a toilet or an improved latrine.

Some 13% of the global population is forced to defecate in the open. Nine out of 10 people who do this live in rural areas but the number defecating in the open in towns and cities is gradually increasing as urban populations grow without a corresponding expansion of sanitation facilities.

The nearly 700 million people who would have been served if the MDG target for sanitation had been met is equal to the number of unserved people in sub-Saharan Africa.

Sanitation and health

Some 842 000 people in low- and middle-income countries die as a result of inadequate water, sanitation and hygiene each year, representing 58% of total diarrhoeal deaths. Poor sanitation is believed to be the main cause in some 280 000 of these deaths.

Diarrhoea remains a major killer but is largely preventable. Better water, sanitation and hygiene could prevent the deaths of 361 000 children aged under 5 each year.

Open defecation perpetuates a vicious cycle of disease and poverty. The countries where open defection is most widespread have the highest number of deaths of under-5s as well as the highest levels of malnutrition and poverty, and big disparities of wealth.

Benefits of improving sanitation

Benefits of improved sanitation extend well beyond reducing the risk of diarrhoea. These include:

  • reducing the spread of intestinal worms, schistosomiasis and trachoma, which are neglected tropical diseases that cause suffering for millions;
  • reducing the severity and impact of malnutrition;
  • promoting dignity and boosting safety, particularly among women and girls;
  • promoting school attendance: girls’ school attendance is particularly boosted by the provision of separate sanitary facilities;
  • potential recovery of water, renewable energy and nutrients from faecal waste.

A WHO study in 2012 calculated that for every $1 invested in sanitation, there was a return of $5.50 in lower health costs, more productivity and fewer premature deaths.

In 2013, the UN Deputy Secretary General issued a call to action on sanitation that included the elimination of open defecation by 2025. Achieving universal access to a basic drinking water source appears within reach but universal access to basic sanitation will require additional efforts.

There is not much reliable data but estimates suggest that up to 90% of wastewater in developing countries is discharged partially treated or untreated directly into rivers, lakes or the ocean.

Wastewater is increasingly seen as a resource providing reliable water and nutrients for food production to feed growing urban populations. But there needs to be:

  • management practices that ensure wastewater is sufficiently treated and safely reused;
  • institutional oversight and regulation;
  • public education campaigns to inform people about wastewater use.

WHO's response

As the international authority on public health, WHO leads global efforts to prevent transmission of diseases, advising governments on health-based regulations.

On sanitation, WHO monitors global burden of disease and the level of sanitation access and analyses what helps and hinders progress. Such monitoring gives Member States and donors global data to help decide how to invest in providing toilets and ensuring safe management of wastewater and excreta.

WHO works with partners on promoting effective risk assessment and management practices for sanitation through Sanitation Safety Planning, Guidelines on Safe Use of Wastewater, Excreta and Greywater, and forthcoming Sanitation and Health Guidelines and Global Strategy on Water, Sanitation and Hygiene and Neglected Tropical Diseases.

WHO is also working with UNICEF on a global action plan for ending preventable child deaths from pneumonia and diarrhoea by 2025. This aims to meet several prevention and treatment targets, including promoting universal access to drinking water, sanitation and hygiene in health care facilities and homes by 2030.

Increasing people’s access to improved sanitation combined with delivering preventive chemotherapy is also part of the 5 global public health strategies for the control and elimination of neglected tropical diseases.

For more information contact:

WHO Media centre


Compositions of White on Light (Composition #4), 2011. Inkjet print, lacquered wooden frame. 38.1 x 37.8 cm. Edition 3 of 6

All images courtesy of the artist and 1301PE.

Uta Barth's recent works [on view through October 29 at 1301PE, Los Angeles; opening Oct. 27 at Tanya Bonakdar, New York] are photographs at their most literal: pictures of light. All the images in the series "...and to draw a bright white line with light" (all work 2011), wrapped along three walls of 1301PE's upstairs space, share the horizon of a windowsill, which is intersected periodically by the irregular curvature of light across a curtain. Depending on the time they were captured and Barth's manipulation of the fabric's slackness, the light's form varies from slender strands to wide swathes spilling through its gauzy texture. These renderings of interiors emphasize optics as they invoke a slow-moving process of looking.

For the series "Compositions of Light on White," the artist opened and closed blinds to produce rectilinear beams of light projected onto a closet. Architectural elements disappear into a hazy, intense monochrome, invoking a tabular, painterly quality, affirmed only by the composition's margin—a sliver of hallway to the left, the diagonals of a stack of drawers to the right. The spatial complications that these forms generate on the picture plane demand double takes, asking that the viewer not only contemplate the work, but also the phenomenological experience of looking itself.

  "Compositions of Light on White" consists of serial images of light projections onto a single architectural feature, your closet doors. The close-up image verges on complete abstraction, and the viewer must spend time staring in order to identify vertical lines as the edges of a door, and a silver form as a hinge, for example. What attracted you to this space, and what formal decisions did you make with respect to your proximity to the subject matter?

  I first noticed the light. For one week in June, the light projected through the raised blinds in my room is perfectly parallel to the lines of the closet door you see here. One reason you read these images as close-ups is that the house and this room is small. I cannot get the camera further away. The camera stays almost exactly in the same place for the work in this series. I was interested in making these compositions by only working with the grid: that of the minimal architecture and the grid of light I could manipulate as it fell onto the doors. The appearance of the image fluctuating is created by cropping them in order to achieve cohesive compositions. I suppose I could use a different camera and other lenses, but I am interested only in the area where the light happens to fall; I am not trying to describe the room.

  The confusion between depth and flatness owes to Vermeer's compositions and Malevich's forms. The abstract, rectilinear shapes in the center are framed by formal slippages in the margins--the appearance of a diagonal in the hallway, or of your set of drawers, as in Composition #2 and Composition #4. This suggests an experience of the work that extends out beyond the photograph itself. Could you tell me about this interplay, or confusion, and its relation to the photograph's overall composition?

  The shadow lines from the built-in drawers on the right complicate one's initial perception of seeing a flat field. At first glance we assume we're looking at totally flat geometric abstractions, but as you point out, a careful look at the edge of most works will suddenly flip the image into three-dimensional space. I have played with the inversion of figure and ground in a desire to see what we normally ignore. Here the margins play two roles: they bring us to seeing deep space where we don't expect it and they also function as carefully framed compositional devices. When you are playing with geometric composition, it is a game of how every field or line relates to the edge—everything is about the edge. Take a Mondrian painting, move the edge or randomly crop it, and the whole composition just falls apart.

  In Compositions #10 and #12, the margins have been cropped altogether, creating very abstract images, though the shadow and diagonals you would expect there have been drawn towards the center of these two compositions. They are like bookends to "White on Light."

  All deep space in these two works is cropped out. Composition #10 is the most minimal work in the show. It gives little information—it could be a drawing, an etching or a painting, as no camera-like representation is visible. So it is the toughest, most stripped-down work in the show (and maybe, for that, my favorite piece). We can understand it, though, in the context of the rest of the work.

Composition #12 is the point of departure for a whole other way to make these images. It tilts one of the closet doors open, ever so slightly, yet the tilt simply reads as a different shade of dark gray and almost flattens out again. I have made many images in which doors move, which create an entirely different type of composition. For now, I wanted to include just one to open up to their possibility.

  The installations of these two bodies of work are distinct. The images from "Compositions of Light on White" are hung as individual photographs, dispersed with no center along the gallery walls, whereas those in ". . . and to draw a bright white line with light" wrap around the space in diptychs and triptychs along the same center at about the average sight line. How does each series' composition carry over into its distinct hang in the gallery?

  By nature of overtly working with geometric composition, the image must be self-contained, so "Compositions of Light on White" exist as individual images. As the edge of the work holds so much importance, it would be lost and destroyed if these images were sequenced. I went as far as using deep, floating frames for these pieces in order to have the shadow of the frame contrast the white of the image and articulate the edge even more. These frames lock the images down and declare them as singular. The installation continues the compositional play onto the wall and the room as whole. The works (none are the same size or format) are not hung on an even center line or spaced at equal intervals. As I did with the "Ground" (1994–95) series, I try to play off the architecture of a particular space. The installation will be different at every place this work is shown. I look at the large rectangle of the wall and try to carry the compositional ideas onto it, and then onto the room as a whole. So a certain image will be balanced by another of a different scale and format, or by a window, corner or doorway in the space.

In the past, I have used sequences to trace time, optical fatigue, retinal memory and melting, fading afterimages. Sometimes the images are just seconds apart, other times they trace the change of light of a single view over the period of a whole year. "...and to draw a bright white line with light" is presented in a collection of segments of varying length. Here the time covered by the entire project is only a few hours. One segment follows the next in a determined order as the line of light grows with the setting of the sun. As the viewer, one stands surrounded by time articulated in light. This series (unlike others, which are circular) has a distinct beginning and end. Included are images of my hand drawing the curtain to change the shape of the line, so we are also watching a long performance. Its duration is determined by the very first appearance of light as it crosses the windowsill, to the end, when the entire frame is taken up by light.

Seeing the same information in repetition so often creates a very contemplative state of mind. Much like Morandi painting the same few bottles and crockery for most of his life, the images become a sort of mantra and allow us to tune in to the subtlest, the most ephemeral information that I am trying to chase down.

  Your arrangement of the curtains and blinds is made visible in both series, marking an explicit turn in your work—we are left with images of your arm, or your arm's shadow, as they induce specific light effects. Could you tell me about why you've included these pieces?

  My work has for long been about observation of that which is so easily overlooked. The work is always about visual perception, so it has been important for me not to manipulate the scene. It is clear that this new work could only be made by my intervention. Perhaps I have just discovered a way to make marks with light that fits into my ongoing practice. Not only is this mark-making what motivated the work; I felt I needed to be very honest about it and therefore include images of my arm drawing the curtain or pulling the blinds.


Roberto Juarez

Robert Miller Gallery

41 East 57th Street

Through Oct. 4

A dreamy, elegiac warmth suffuses Roberto Juarez's pleasant but somewhat empty paintings, which were inspired by a Prix de Rome sojourn in Italy. With a relaxed, expressionistic touch, he paints flowers, fruit, classical statuary and architectural ornament against flat, tropically hued backgrounds. The way these stray bits of memory hover in tropically hued spaces, it's as though we could see into the mind of someone half asleep basking in the Mediterranean sun.

This floating imagery is grounded by the material dimension of Mr. Juarez's canvases.

Layering generous swatches of paint and large sheets of gauzy paper in rectilinear compositions, he builds surfaces that look like sections of ancient walls. KEN JOHNSON


© 2016 Shmoop University, Inc. All rights reserved.

Theseus's Clique: Student Court

When there's a dispute on campus that needs to get solved, this clique swoops in to make sure that justice gets served. Despite what you might think, Theseus totally fits into this clique. Sure, Theseus is known as a big-time hero always ready for a fight and a major Don Juan who leaves a string of broken hearts in his wake. But he is also the dude that brings law and order to Athens. His name even means "to set" or "to order." So yeah, this definitely gets him a spot in this justice-serving clique.

Nemesis and The Furies

According to some mythologies, these punishment-bringing ladies are often thought to be sisters. They all come complete with wings, a whip, and a burning desire to make evildoers pay.

Themis (Justitia, Lady Justice)

This Titan goddess was Zeus's wife before Hera and was kind of like the grandmamma of all the Greek goddesses of justice. Being the big mamma in the sky, she's usually in charge of divine law and order, not messing around with the day-to-day rights and wrongs of humans. Like a lot of justice goddesses, her best friend is her set of scales. Later on, she became Lady Justice and was shown wearing a blindfold and holding a double-edged sword along with her scales.

Dike is Themis's daughter by Zeus, and just like her Mom, she is all about justice. While Themis was more into heavenly law and order, Dike makes sure everything is going like it ought to down on Earth. Dike is thought of as one of the Horai (the Hours), and along with her sisters Eunomia (Good Order) and Eirene (Peace), she helps guard the gates of Olympus. Dike's main enemy is a demoness named Adikia (Injustice). Whenever she gets a chance, Dike likes to beat her trouble-causing rival with a club. Sounds like a fun party game, right?

This Egyptian goddess of justice hangs out in the Land of the Dead and has a pretty cool system for checking to see if your ka (or soul) is good enough for ever lasting. Basically, she puts your ka on one side of a scale and a feather on the other. If your soul is lighter than the feather, then—hurray!—you can look forward to a happy, blessed afterlife. If your soul is heavier than a feather, though, you get gulped down by Ammit, a hippo-crocodile-lion monster. So we suggest that before you go visit Ammit, you take your ka to the gym or something.

Forseti is a Norse god of justice and order who spends his time chilling in a shining golden courtroom with a brilliant silver ceiling. (Evidently, there aren't many budget cuts in Norse mythology land.) You have nothing to fear when you stand before Forseti—if you're innocent, at least. From what everybody says, he's fair and impartial and never makes a mistake.

People who Shmooped this also Shmooped...


Robert Kaplan’s op-ed on Patrick Leigh Fermor in the New York Times, “The Humanist in the Foxhole,” stands alone as a cool piece of writing worth studying.

Kaplan writes:

Unlike the young Winston Churchill in Sudan or the Prussian general Helmuth von Moltke journeying through the Ottoman Empire, Fermor and his friends refused to reduce the world to questions of strategy and national interest: they were more taken by culture and landscape, which in fact made them more valuable than most intelligence agents.

 Because America’s own security will rest in a world where tribes matter as much as Twitter, Fermor is an icon of the kind of soldier, diplomat or intelligence expert we will need: someone who can seamlessly move from any one of these jobs to another, who is equally at home reading a terrain map as he is reciting the poetry of the people with whom he is dealing. The more depth and rarity of knowledge we can implant in our officials, the less likely they are to serve up the wrong options in a crisis. But as Fermor shows, knowledge can’t be selectively learned for utilitarian ends. He was driven by the kind of appreciation of beauty with which life itself is sanctified.

This is the finest—and most succinct—argument for hearts and minds we’ve ever read. Kaplan writes beautifully, clearly, and without any pretension. He makes his case. But as literary criticism, we had our respectful reservations. Kaplan gives this example of a sentence he loved from Fermor:

“Arcadia is the double flute, Arachova the jingle of hammers on the strings of a dulcimer, Roumeli a klephtic song heckled by dogs and shrill whistles, Epirus the trample of elephants, the Pyrrhic stamp, the heel slapped in the Tsamiko dance, the sigh of Dodonian holm-oaks and Acroceraunian thunder and rain.”

This example belies a generational shift. Most thirty-something English boys raised on hard diets of the Great Game and T.E. Lawrence will attest: it wasn’t Fermor’s writing so much as what he represented that made him a model. One young English novelist put it this way: “he captured really bad guys; we cannot fault him heavy prose.” Why do his sentences seem so archaic?

Heavy prose was in vogue then. Were readers more patient? No. You could say that before Raymond Carver, a generation of writers considered the apotheosis of their craft to be more, not less. But that’s not true, either. Are there too many additional, happy distractions to prevent writers from searching for words like “klephtic?" today? No. But, as Kaplan points out, what we loved about Fermor was that he lived what he wrote. Pollock was an action painter, and Fermor was an action writer. Like Kapuscinski, he was sui generis.

There must be Fermors in foxholes right now. What will their writing be like? Maybe something more like this


Is the Electric Company Liable For Injuries Caused by Power Outages?

With Hurricane Sandy blowing through many people and businesses are expected to lose power.  As a result of the loss of power there are likely to be many injuries and damages.  People may trip and fall in darkened staircases, food in homes and grocery stores will go bad without refrigeration, and car accidents may occur due to lack of traffic lights.   Can the power companies be held liable for loss of power during a storm? Usually, the electric companies, such as Con Ed, LIPA, etc. cannot be held accountable for loss of power during a storm except under special circumstances.

The New York State Court of Appeals has held that the liability of a public utility should be limited to damages arising from the utility’s willful misconduct or gross negligence.  This is because most suppliers of electricity in New York under the tariff or rate schedule filed with the Public Service Commission (PSC) has a provision which sates that they:

 will endeavor at all times to provide a regular and uninterrupted supply of service, but in case the supply of service shall be interrupted or irregular or defective or fail from causes beyond its control or through ordinary negligence of employees, servants or agents, the Company will not be liable therefor.

Current New York Law on the issue was clarified following the 1977 New York City wide blackout caused by two lightning strikes hitting Con Ed equipment.  At a trial in the case of FOOD PAGEANT, INC., v. CONSOLIDATED EDISON CO., it was held that Con Ed was grossly negligent in maintaining their facilities and reacting to the storm and lightning strikes.  A jury agreed and the courts upheld the verdicts.  Thus any person who had a contract for power with Con Ed and who was damaged due to a loss of that power was entitled to recover for their damages.  However, the utility did not owe any duty to those persons who lacked a direct contractual arrangement with it.

Specifically the New York State Court of Appeals has held that:

that in the case of a blackout of a metropolis of several million residents and visitors, each in some manner necessarily affected by a 25-hour power failure, liability for injuries in a building’s common areas should, as a matter of public policy, be limited by the contractual relationship

The issue has since been revisited following other storms.  In the case of DUNLAY v. NIAGARA MOHAWK POWER CORPORATION the court held that

The storm of October 3–4, 1987 was an unprecedented “Act of God.” Nature caused the outage, not any negligence on the part of the defendant. But, what of the restoration? Can any gross negligence be imputed to defendant regarding the restoration efforts? On the record before it, the Court thinks not.

Similarly, following another blackout it was held in the case of  SCHLESINGER v. CON EDISON COMPANY OF NEW YORK, INC. that:

This Court finds that the evidence gathered to date indicates that the August 14, 2003 blackout resulted from events outside of Con Edison’s service area and was not caused by a failure of Con Edison’s local distribution system. No evidence has been presented proving that Con Edison was either negligent or grossly negligent in causing the August 14, 2003 blackout. Con Edison restored service as soon as practical. Under the circumstances in the instant case, there is no liability by defendant for claimant’s food spoilage and therefore for any damages proximately caused by the August 14–15, 2003 interruption of electric service to claimant’s premises.

So, will the power companies be held liable for damages caused by blackouts in October of 2012? Only if it can be shown that the damages were caused by the gross or willful negligence of the power company, and that the damages were incurred by a customer of the power company due to loss of power to be supplied under an agreement.

Of course the electric companies can be sued for their ordinary negligence in many other situations, other than loss of power, and an attorney should be contacted to determine your rights in any specific situation.  Also, entities other than the power company may be responsible for accidents incurred during a blackout.

If you believe that you have been injured due to the actions or negligence of a Power or Utility Company, or any other entity,  you should contact an attorney.  Zalman Schnurman & Miner are personal injury attorneys dedicated to representing the accident victims.  For a free consultation call 1-800-LAWLINE (1-800-529-5463).

Comments are closed.


UltraVISTA Survey Data Release 1

Provided by: Jim Dunlop

Release Date: 15/02/2012

The UltraVISTA program aims to provide extremely deep near-infrared YJHKs and narrow-band NB118 photometry on the COSMOS field. The survey is divided into two components, the "deep" component which covers a 1.5 x 1.2 deg contiguous region in the COSMOS field, and the "ultra-deep" component which covers 4 ultra-deep stripes in the field (cf. Figs. 1a,b). This first data release comprises part of the "deep" component and contains stacked, sky-subtracted images in Y,J,H,Ks and NB118 from the first year of data-taking. Single band and multi-band aperture matched catalogues are also provided.

Overview / Layout of observations

All the stacks released here cover part of the COSMOS field. Figure 1a shows the field layout on the COSMOS CFHT i-band image. The area of the green box is ~1.5 deg2. The green box corresponds to the coverage in the broad-band images (i.e. to the contiguous region); it has corners 9:57:13,02:48:00 (NW) and 10:03:00,01:37:00 (SE). Note that in the actual stacks, some data is missing in the bottom south-east corner due a bad detector on VIRCAM. Figure 1b shows schematically the deep and ultra-deep components of the UltraVISTA survey, in addition to the area covered by ACS/HST. Figure 1c shows the 5 images.

Figure 1a. Location of the UltraVISTA deep data (green box) superimposed on the COSMOS i-band data from CFHT. North is up and west (note!) is to the left in this figure.

Figure 1b. UltraVISTA Ultra-deep and deep surveys and ACS coverage. North is up and east is to the left.

Figure 1c. The 5 stacks, top: Y, J, H; bottom: Ks, NB118. The images have been displayed using intensity cuts -5,15 "ADU" (cf. the colour bar), with the "ADU" in these images corresponding to a zero point of 30.0 in AB magitude. North is up and east is to the left, and the layout corresponds to Fig. 1b.

Release Content

All stacks have a common tangent point corresponding to the COSMOS field (Scoville et al. 2007) as well as the same zero point and pixel scale:
Zero point
Pixel scale
Tangent point
(decimal degrees)
150.116, 2.2000
The characteristics of each stack is as follows:
Table 1. Characteristics of UltraVISTA stacks.
Filename Filter Av. Exposure per. pixel Mean FWHM (" +/- 0.1") 5-sigma 2" ap. (AB MAG; +/- 0.1 mag) 95% completeness
UVISTA_Y_27_04_11_skysub_015_v1.fits Y 42360 0.82 24.6 24.2
UVISTA_J_03_04_11_skysub_015_v1.fits J 49720 0.79 24.7 24.2
UVISTA_H_26_04_11_skysub_015_v1.fits H 42520 0.76 23.9 24.1
UVISTA_Ks_15_12_10_skysub_015_v1.fits K 39400 0.75 23.7 23.8
UVISTA_NB118_20_08_11_skysub_015_v1a.fits NB118 23773 0.75 22.9+/-0.2 TBD

The limiting magnitude for each filter is computed using the 5-sigma standard deviation in 2" diameter apertures scattered randomly over the field. The completeness measurements are computed as the magnitude at which 95% of random stellar sources injected into the real field can be successfully recovered.

Note that the large size of these images means than to display or manipulate them may require a machine with a 64bit architecture and sufficient memory (nominally 8Gb).

Release Notes

Input images and image selection

The images in this release were taken between 5th December 2009 and the 19th of April 2010. This does not consist of the complete number of images taken for the UltraVISTA program in the 2009-2010 observing season; subsequently, around 10% additional images in H and Ks were made available by CASU using a different pipeline processing, after we had already graded the first batch of images. In order to maintain as a homogenous as possible data set, we restrict in this current release ourselves to this initial batch. However, had we included these data, the average exposure time per pixel would have been 4800 s and 5400 s higher in H and Ks respectively, i.e. around 10%.

The images considered here were all processed used v0.8 of the CASU release. In total, we consider 7031 individual images (each of which is a single multi-extension fits image containing 16 image extensions for each of the VISTA detectors). We do not use the confidence maps provided by CASU, but create our own weight-maps from the supplied flat-fields and bad pixel maps.

These images were inspected and graded in the YOUPI environment at the TERAPIX data processing centre at the IAP, Paris. Images were assigned a grade of A, B (usable for science), C, D (rejected). Figure 2 and 3 show the five-filter seeing and ellipticity distributions for all images considered for this release, divided by image classification. Note that the distribution for each object class has been rescaled accordingly.

Based on these distributions we decided to keep all images which have stellar 1.0" and ellipticity <0.1 and which were classified A, B based on visual inspection. The visual inspection process in general finds images which have bad PSFs or other optical defects which would have not been found by a typical seeing or ellipticity cut (for example, tracking problems which produce double-lobed PSFs). In total we reject 426 images or around 6% of the total.

Fig. 2. Seeing distribution

Fig. 3. Ellipticity distribution

Outline of image processing

We adopted the same set of processing steps for each of the five filters. After image selection, we processed the CASU sky-subtracted images (by which we mean astrometric solution, weight map generation, and stacking) to make a ``first-pass'' stack to derive the object mask for each image. For these images we used the TERAPIX QualityFITS tool to create weight-maps from the corresponding flat-fields supplied in the release and image catalogues. Using scamp we computed astrometric and photometric solutions using as reference catalogue the COSMOS i-band astrometric reference catalogue, described in Capak et al. 2007.

To create our sky-subtracted images, we use a set of tools developed at TERAPIX. To summarise, we start by ``adding back'' to each image the sky background frames subtracted by CASU, supplied as part of the original data release. Based on the first pass-stack and astrometric solutions, we compute object masks for each individual image. Next, we use these object masks (appropriately warped to match the images to compute and subtract a running sky for each individual image, based on a median of images taken during a 20 minute timescale. After the subtraction of the running sky, we re-''destripe'' the images and remove large-scale background gradients using sextractor. In the final step weight maps and catalogues are created for each image. Saturated objects, based on an examination of the stellar locii, are flagged in the input catalogues. These catalogues are used to compute the final astrometric and photometric solutions. Note that we use the photometric solutions supplied by CASU for their .st stacks as initial approximate photometric solutions for our individual images. All these images are marked as ``photometric'' , although re-scalings are allowed based on overlapping images.

In the last step, the images are coadded using a modified version of the software which permits combination of images based on a clipped sigma estimator; we use a clipping threshold of 2.8 sigma. Bad regions on individual detectors, such as half of detector 16, are also masked, which explains the irregular appearance in the SE corner of the stacked images (cf. Fig. 1c).

Given the dense sampling for the astrometric reference catalogue, and the large amount of overlap between exposures, our astrometric accuracy is excellent, with r.m.s values much smaller than one pixel, typically ~0.1" compared to the external catalogue and ~0.05" internally.

Stacked data products

In this release Y,J,H, K and NB118 stacked images and their corresponding weight maps for data taken during the first year of public survey operations of the UltraVISTA survey are made available. The images have a zero point of 30.0AB magnitudes and a pixel scale of 0.15"/pixel. The CASU VEGA magnitudes are converted to the AB system by applying the offsets detailed in Table 2 below. These offsets were calculated from the VISTA filter curves and detector efficiency curves. The images all have a common tangent point, in decimal RA,DEC of (150.116, 2.2000), corresponding to the tangent point of the publicly available IRSA/COSMOS images. The uncompressed image is ~9Gb and has a size of 48096x48096 pixels (note that the large amount of blank pixels in these images is primarily so they correspond to publicly-available COSMOS data).

Table 2. Corrections applied to covert from VEGA to AB magnitudes.
Filter Correction to AB (AB=Vega+x)
Y +0.61
J +0.92
H +1.38
Ks +1.84
NB118 +0.85

Two sets of catalogues are supplied: source lists extracted on single images, and "dual-mode" catalogues where the Ks band is used as a detection image. These catalogues, since they share the same detection list, can be used to easily measure colours for each object. These catalogues are meant as preliminary catalogues and have not yet been validated extensively, and should be used with caution. No masks have been applied; the catalogues contain all objects to the specified detection threshold. Aperture magnitudes reported in the catalogues are measured in 2" and 7" diameters respectively.

Quality assessment

We have carried out an extensive set of quality assessment tests on the full mosaics. In addition we have computed the colour-colour diagrams of faint and bright stars. These tests are explained in detail in the accompanying data paper. Figure 4. shows the comparison of 2MASS magnitudes with UltraVISTA magnitudes. In the zone where 2MASS and UltraVISTA magnitudes are both reliable, both catalogues agree well, to within 0.05 magnitudes.

In Figure 5. we compare the positions of sources in our K-band stack with 2MASS stars. The origin of slight offset in RA we observe is because we use the COSMOS astrometric reference catalogue which is not tied to 2MASS. Comparisons with HST-ACS data (detailed in the accompanying data paper) show no offsets.

Fig. 4. Magnitude comparison with 2MASS
Fig. 5. Astrometric position comparison with 2MASS
Figure 6. shows the colour-colour diagram of bright (18.75 < KAB < 19.0) and faint (19.5 < KAB < 20.5) stars using optical-near infrared colours; the position of this locus is constant with magnitude, indicating our stacks are free of any systematic effects at fainter magnitudes.
Fig. 6. Bright and faint stars in the BzK diagram

Data Format

The following table contains a complete list of files provided in the release, and the following file naming convention is used: all filenames start with UVISTA_, followed by the filter name, followed by the creation date of the stack, followed by "skysub" indicating that these are images which were generated using the TERAPIX sky-subtracted individual images. Catalogues are delivered as standard binary FITS tables.
Stacked science images Weight map
UVISTA_Y_27_04_11_skysub_015_v1.fits UVISTA_Y_27_04_11_skysub_015_v1.weight.fits
UVISTA_J_03_04_11_skysub_015_v1.fits UVISTA_J_03_04_11_skysub_015_v1.weight.fits
UVISTA_H_26_04_11_skysub_015_v1.fits UVISTA_H_26_04_11_skysub_015_v1.weight.fits
UVISTA_Ks_15_12_10_skysub_015_v1.fits UVISTA_Ks_15_12_10_skysub_015_v1.weight.fits
UVISTA_NB118_20_08_11_skysub_015_v1a.fits UVISTA_NB118_20_08_11_skysub_015_v1a.weight.fits
Single-band catalogues Multi-colour catalogues(detection on Ks image)
UVISTA_Y_27_04_11_skysub_015_v1_cat.fits UVISTA_Ks_15_12_10_skysub_015_v1_Y_cat.fits
UVISTA_J_03_04_11_skysub_015_v1_cat.fits UVISTA_Ks_15_12_10_skysub_015_v1_J_cat.fits
UVISTA_H_26_04_11_skysub_015_v1_cat.fits UVISTA_Ks_15_12_10_skysub_015_v1_H_cat.fits
UVISTA_Ks_15_12_10_skysub_015_v1_cat.fits N/A
UVISTA_NB118_20_08_11_skysub_015_v1a_cat.fits UVISTA_Ks_15_12_10_skysub_015_v1_NB118_cat.fits

Note that filenames provided by the ESO archive are different than the filenames here; these filenames are given by the ORIGFILE header keyword. This script will rename the ESO images to match the UltraVISTA naming convention.

Data retrieval

Go to the data products query form to find and retrieve the data from the ESO Science Archive. Just press the Search button to find all data belonging to this release, or specify search constraints to find a subset thereof.

Users of this release should cite "McCracken et al. 2012 (in prep.)"; a draft of this paper is available from the ultravista release site ultravista.org/release1/. The data source should be acknowledged as follows:

Based on data products from observations made with ESO Telescopes at the La Silla Paranal Observatory under ESO programme ID 179.A-2005 and on data products produced by TERAPIX and the Cambridge Astronomy Survey Unit on behalf of the UltraVISTA consortium.


Does yoga help with chronic back pain?  Yes it does, but so does stretching.  Either is better than handing people a book, according to the largest U.S. randomized controlled trial of yoga to date.

In the trial, 228 adults in six cities in western Washington state were randomly assigned to 12 weekly 75-minute classes of either yoga or stretching exercises or a comprehensive self-care book called "The Back Pain Helpbook". Nine in 10 of them were primary-care patients at Group Health Cooperative and participants in the trial typically had moderate, but not severe, back pain and relatively good mental health. Most had been at least somewhat active before the trial started.

The class participants received instructional videos and were encouraged to practice at home for 20 minutes a day between their weekly classes. Interviewers who didn't know the patients' treatment assignments assessed their back-related function and pain symptoms at six weeks, 12 weeks, and six months.

"We found yoga classes more effective than a self-care book—but no more effective than stretching classes," said study leader Karen J. Sherman, PhD, MPH, a senior investigator at Group Health Research Institute. Back-related function was better and symptoms were diminished with yoga at 12 weeks; and clinically important benefits, including less use of pain medications, lasted at least six months for both yoga and stretching, with thorough follow-up of more than nine in 10 participants.

In 2005, Sherman and her colleagues conducted a smaller study that found yoga effective for easing chronic low back pain. "In our new trial," she said, "we wanted both to confirm those results in a larger group and to see how yoga compared to a different form of exercise of comparable physical exertion: stretching.

Both the yoga and stretching classes emphasized the torso and legs:

  • The type of yoga used in the trial, called viniyoga, adapts the principles of yoga for each individual and physical condition, with modifications for people with physical limitations. The yoga classes also used breathing exercises, with a deep relaxation at the end.

  • The stretching classes used 15 different stretching exercises, including stretches of the hamstrings and hip flexors and rotators. Each was held for a minute and repeated once, for a total of 52 minutes of stretching. Strengthening exercises were also included.

"We expected back pain to ease more with yoga than with stretching, so our findings surprised us," Sherman said. "The most straightforward interpretation of our findings would be that yoga's benefits on back function and symptoms were largely physical, due to the stretching and strengthening of muscles."

"Our results suggest that both yoga and stretching can be good, safe options for people who are willing to try physical activity to relieve their moderate low back pain," Sherman concluded. "But it's important for the classes to be therapeutically oriented, geared for beginners, and taught by instructors who can modify postures for participants' individual physical limitations."

Published in the Archives of Internal Medicine


Insomnia - Understanding Insomnia -- Treatment

Antidepressant drugs may be used in people with depression to help with sleep. They are not approved for the treatment of insomnia. These may cause daytime sleepiness or other side effects.

Ramelteon (Rozerem) is an insomnia medication that works differently than the other sedative medications. It is less likely to cause morning sleepiness or to be addictive.

Over-the-counter sleep drugs usually contain an antihistamine. Antihistamines are often used for allergies, but they have a side effect of drowsiness. These medications may cause daytime sleepiness and dry mouth along with other side effects.

Many poor sleepers simply need help relaxing. If you're a habitual insomniac and trying to get to sleep just makes you more anxious and awake, try these alternative choices to help reduce your worry about sleep while relaxing your body and mind. If the root cause of insomnia is stress, any treatment must address the problem of stress in your life.

Breathing exercises can promote relaxation. Here's a routine you can do anywhere, anytime:

  1. Exhale completely through your mouth.
  2. Inhale through your nose to a count of four.
  3. Hold your breath for a count of seven.
  4. Exhale through your mouth for a count of eight.
  5. Repeat the cycle three times.

Moderate exercise can help you sleep better and give you more energy while awake. Aim for a 20- to 30-minute routine three or four times a week. Tailor the workout to your physical condition, and exercise in the morning or afternoon, not close to bedtime. Check with your doctor about how much and what type of exercise is right for you.

Mind/Body Medicine

Meditation, yoga, and biofeedback may reduce tension and promote better sleep. Visualization or guided imagery, during which you hold a peaceful image in your mind before bedtime, can also be an effective path to relaxation. You can learn these techniques from an instructor, online sites, a how-to book, or an instructional tape.

Good Sleep Habits

Be sure your bedroom is quiet and dark. Eye shades may help since light comes in even through closed eyelids.


Browse Results What Format Should I Choose?

Showing 1 through 12 of 12 results

The Attention Revolution

by Daniel Goleman B. Alan Wallace

Meditation offers, in addition to its many other benefits, a method for achieving previously inconceivable levels of concentration. Author B. Alan Wallace has nearly thirty years' practice in attention-enhancing meditation, including a retreat he performed under the guidance of the Dalai Lama. An active participant in the much-publicized dialogues between Buddhists and scientists, Alan is uniquely qualified to speak intelligently to both camps, and The Attention Revolution is the definitive presentation of his knowledge. Beginning by pointing out the ill effects that follow from our inability to focus, Wallace moves on to explore a systematic path of meditation to deepen our capacity for deep concentration. The result is an exciting, rewarding "expedition of the mind," tracing everything from the confusion at the bottom of the trail to the extraordinary clarity and power that come with making it to the top. Along the way, the author also provides interludes and complementary practices for cultivating love, compassion, and clarity in our waking and dreaming lives. Attention is the key that makes personal change possible, and the good news is that it can be trained. This book shows how.

Buddhism and Science: Breaking New Ground

by B. Alan Wallace

Distinguished philosophers, Buddhist scholars, physicists, and cognitive scientists examine the contrasts and connections between the worlds of Western science and Buddhism. Contributors, the Dalai Lama among them, assess not only the fruits of inquiry from East and West, they shed light on the underlying assumptions of these disparate world views.

Contemplative Science: Where Buddhism and Neuroscience Converge

by B. Alan Wallace Brian Hodel

B. Alan Wallace, renowned Buddhist scholar, integrates the contemplative methodologies of Buddhism and Western science into a single discipline: contemplative science. The science of consciousness investigates the mind through Buddhist contemplative techniques, such as shamatha, an organized, detailed system of training the attention. Just as scientists make observations and conduct experiments with the aid of technology, contemplatives have long tested their theories with the help of highly developed meditative skills of observation and experimentation. Contemplative science allows for a deeper knowledge of mental phenomena, and its emphasis on strict mental discipline counteracts the effects of conative (intention and desire), attentional,cognitive, and affective imbalances. Just as behaviorism, psychology, and neuroscience shed light on the cognitive processes enabling us to survive and flourish, contemplative science offers a groundbreaking perspective for expanding our capacity to realize genuine well-being. It also forges a link between the material world and the realm of the subconscious, transcending a traditional science-based understanding of the self.

Heart of the Great Perfection: Dudjom Lingpa's Visions of the Great Perfection

by B. Alan Wallace Dudjom Lingpa

The revelations of Düdjom Lingpa, a highly influential mystic of 19th century Tibet, translated by B. Alan Wallace, widely respected for his lucid and readable translations of Tibetan Buddhism. Düdjom Lingpa (1835-1904) was one of the foremost tantric masters of his time. This new series includes his visionary teachings on the Great Perfection (Dzogchen), the pinnacle of practice in Tibet's oldest Buddhist school. Volume 1 contains four works explaining the view and practice of the Great Perfection, the signature style of meditation of the Nyingma school of Tibetan Buddhism: The Sharp Vajra of Conscious Awareness Tantra: This work is considered the root distillation of Düdjom Lingpa's wisdom. Essence of Clear Meaning: This definitive commentary, which unpacks the quintessential verses of The Sharp Vajra, is based on Düdjom Lingpa's oral teachings recorded by his disciple Pema Tashi. The Foolish Dharma of an Idiot Clothed in Mud and Feathers: Düdjom Lingpa narrates the essential Dharma teachings from the perspective of an old man rejecting superficial appearances. The Enlightened View of Samantabhadra: A masterful exposition of the Great Perfection is revealed as a dialogue between wisdom beings who bestow a treasury of pith instructions and specific advice for practitioners. While the teachings in this series have inspired generations of Tibetans, few have been published in translation--until now.

Hidden Dimensions: The Unification of Physics and Consciousness

by B. Alan Wallace

Bridging the gap between the world of science and the realm of the spiritual, B. Alan Wallace introduces a natural theory of human consciousness that has its roots in contemporary physics and Buddhism. Wallace's "special theory of ontological relativity" suggests that mental phenomena are conditioned by the brain, but do not emerge from it. Rather, the entire natural world of mind and matter, subjects and objects, arises from a unitary dimension of reality that is more fundamental than these dualities, as proposed by Wolfgang Pauli and Carl Jung. To test his hypothesis, Wallace employs the Buddhist meditative practice of samatha, refining one's attention and metacognition, to create a kind of telescope to examine the space of the mind. Drawing on the work of the physicist John Wheeler, he then proposes a more general theory in which the participatory nature of reality is envisioned as a self-excited circuit. In comparing these ideas to the Buddhist theory known as the Middle Way philosophy, Wallace explores further aspects of his "general theory of ontological relativity," which can be investigated by means of vipasyana, or insight, meditation. Wallace then focuses on the theme of symmetry in reference to quantum cosmology and the "problem of frozen time," relating these issues to the theory and practices of the Great Perfection school of Tibetan Buddhism. He concludes with a discussion of the general theme of complementarity as it relates to science and religion. The theories of relativity and quantum mechanics were major achievements in the physical sciences, and the theory of evolution has had an equally deep impact on the life sciences. However, rigorous scientific methods do not yet exist to observe mental phenomena, and naturalism has its limits for shedding light on the workings of the mind. A pioneer of modern consciousness research, Wallace offers a practical and revolutionary method for exploring the mind that combines the keenest insights of contemporary physicists and philosophers with the time-honored meditative traditions of Buddhism.

Meditations of a Buddhist Skeptic

by B. Alan Wallace

"B. Alan Wallace displays courage in raising central Buddhist themes such as past-life recall, extrasensory perception, other paranormal abilities, and the realization of emptiness and buddha nature. In his description of the tenets and practices of Buddhism, Wallace is a true master. His range and depth of knowledge to the presence and views of science is nearly unique. Book jacket.

Mind in the Balance

by B. Alan Wallace

Natural Liberation

by Padmasambhava B. Alan Wallace Gyatrul Rinpoche

In life and in death, in meditation and in sleep, every transitional stage of consciousness, or bardo, provides an opportunity to overcome limitations, frustrations, and fears. The profound teachings in this book provide the under- standing and instruction necessary to turn every phase of life into an opportunity for uncontrived, natural liberation. Like the Tibetan Book of the Dead, Natural Liberation is a term, a "hidden treasure" attributed to the eighth-century master Padmasambhava. Gyatrul Rinpoche's lucid commentary accompanies the text, illuminating the path of awakening to the point of full enlightenment. Natural Liberation is an essential contribution to the library of both scholars and practitioners of Tibetan Buddhism.

Sleeping, Dreaming, and Dying

by Thupten Jinpa His Holiness the Dalai Lama B. Alan Wallace Francisco J Varela

Stilling the Mind

by B. Alan Wallace Brian Hodel

In his previous book, The Attention Revolution, bestselling author Alan Wallace guided readers through the stages of shamatha, a meditation for focusing the mind. In Stilling the Mind, he uses the wisdom of Dzogchen--the highest of all the meditation traditions--to open up the shamatha practice into a space of vast freedom. Here, Wallace introduces us to Dudjom Lingpa's Vajra Essence, one of the most cherished works of the Nyingma school from which Dzogchen stems. With his trademark enthusiasm and keen intelligence, Wallace makes obscure concepts intelligible to contemporary readers and allows us to glimpse the profound realizations of a great nineteenth-century spiritual adept.

Tibetan Buddhism from the Ground Up: A Practical Approach for Modern Life

by B. Alan Wallace Steven Wilhelm

Transcending Time

by His Holiness the Dalai Lama B. Alan Wallace Gen Lamrimpa Pauly B. Fitze

Inspired by years of scholarly training and decades of solitary retreat, Tibetan monk Gen Lamrimpa offers a concise overview of all phases of the Kalachakra practice: the preliminaries, the initiation, and finally, the stages of generation and completion. With remarkable clarity, he makes the Six-Session Guruyoga practice accessible to all practitioners, and deepens our understanding and appreciation of this sublime teaching of the Buddha. Gen Lamrimpa begins this eminently practical explanation by emphasizing the importance of a compassionate motivation for spiritual practice. He then explores the nature of suffering and the cycle of existence that traps all living beings, and concludes with a detailed account of the Six-Phase Yoga, which is meant to be recited and contemplated three times during the day and three times at night. Alan Wallace's introduction illuminates both Kalachakra's rich history and Gen Lamrimpa's unique contribution to our understanding. This book provides a clear explanation of Kalachakra as set forth within the context of the Six-Session Guruyoga, a daily meditation practice for initiates. Transcending Time presents all phases of Kalachakra practice--the preliminaries, the initiation, and finally, the stages of generation and completion.

Showing 1 through 12 of 12 results


Reason Foundation

Reason Foundation

Adding FAST Lanes to Milwaukee's Freeways

Congestion Relief, Improved Transit, and Help with Funding Reconstruction

Robert Poole and Kevin Soucie
February 1, 2006

Executive Summary

Greater Milwaukee has a large and growing problem of traffic congestion. In 1982, the average resident spent five hours per year stuck in traffic. By 2003, that total had grown to 23 hours. Trips at rush hour now take more than 20 percent longer to make than at other times of day. The cost of wasted time and fuel averages $310 per person per year in the Milwaukee area, and is likely to grow significantly in coming decades.

Freeway congestion has also had a devastating impact on bus service and has severely hindered transit’s time-savings competitiveness with the automobile. “Freeway Flyers,” stuck in the same traffic jams as cars, have lost their “express bus” advantage as an alternative for commuters. As a result, transit continues to lose commuter market share, circling down the death spiral of service cuts and fare increases.

One seldom discussed cost of freeway congestion is the greatly reduced ability of emergency vehicles (police, fire, paramedic) to get where they need to go rapidly and reliably. In responding to life-threatening emergencies, every second counts. Yet congested freeway lanes may make it impossible for these public safety vehicles to get through when they are urgently needed.

Some may attribute recent traffic delays to construction work on the Marquette Interchange—and that may be partially correct. But it is a mistake to think that traffic jams will go away once the Marquette is completed. In fact, all evidence indicates that traffic congestion will continue to worsen. Southeastern Wisconsin is in the early stages of a $6.2 billion reconstruction and modernization of its aging freeway system. Simply widening much of the system by adding one lane in each direction (as proposed by SEWRPC) will reduce congestion initially, but projected growth will overwhelm the expanded system in the not-too-distant future—and support is unlikely for further widening due to costs, political opposition, and land-use constraints. Hence, this reconstruction cycle may be the last real chance the region has to consider a more sustainable longterm approach to its freeway system.

This report proposes that on the most congested core portion of the rebuilt freeway system, the inner lane in each direction be configured as a “FAST Lane,” on which traffic always flows at the freeway speed limit thanks to variable pricing—adjusting tolls to maintain free-flow traffic conditions. The use of pricing means there will be tolls, but no toll booths. The variable tolls will be charged electronically, via transponder. There is no need for stopping, slowing down, or using coins. Nearly a decade of experience with such priced lanes on two California freeways shows that variable pricing works well to keep such lanes flowing freely, at the speed limit, during highly congested peak periods. The pricing also generates revenue that more than covers the cost of constructing the FAST Lanes.

FAST Lanes assure motorists that no matter how bad traffic gets, they will always have a reliefvalve available when they really need it. Some have begun to call this concept “congestion insurance.” Just as people purchase insurance to guard them against life’s other hazards (fire, theft, accidents), with a network of FAST Lanes they will be able to purchase insurance to guard them against being late. The initial cost of this “insurance” is very low: simply the cost of opening an account and installing a transponder on the car’s windshield. From that point on, account-holders have the peace of mind that whenever they are running late and really need to be somewhere on time, they have a means of buying that faster trip for a price that is lower than the cost of being late. This will always be true since it will be the individual driver who chooses whether or not to pay for a specific trip. Data from the long-established California HOT lanes support the premise that most people don’t use these lanes every day (which for most would be quite costly). Rather, the overwhelming majority uses the lanes in the “congestion insurance” mode, once or twice a week. Data also show that the system is popular with people of all income levels, so all segments of society benefit from the availability of FAST Lanes.

The proposed FAST Lanes system would encompass the approaches to downtown on I-94 from the south and from the west, on I-43 and US 45 from the north, plus the inner core of freeways near downtown (I-894 and I-94/43 north-south, and I-94 and I-43 east-west). This is the portion of the freeway system where congestion is projected to be worst, even after the widening. It is consequently the area where relief is most needed and where willingness to pay to avoid congestion will be greatest. Our proposed construction phasing of the FAST Lanes is designed to get the highest revenue-producing segments in operation first.

Our analysis projects traffic on the freeways and on the FAST Lanes segments through 2045. Based on a starting rush-hour toll equivalent to 15 cents/mile (in 2005 dollars), we estimate that the proposed FAST Lanes would generate enough revenues to support a toll revenue bond issue of about $1 billion. To put it in perspective, that kind of new voluntary (non-tax) revenue could finance the cost of rebuilding the entire Marquette Interchange with money left over. It certainly would make a significant contribution toward the $6.2 billion cost of the overall freeway reconstruction program.

FAST Lanes also provide uncongested guideways for express buses, enabling Freeway Flyers, UBUSes (University buses) and other transit services to operate faster, more efficiently, and more reliably than on regular, congested freeway lanes. Restoration of the time-savings advantage can help transit recapture some of its lost share of the commuter market. In addition, FAST Lanes will provide a greatly improved means for emergency vehicles to reach the scene of incidents, or to get to the portion of the metro area where they need to be, in significantly less time.

This Study's Materials

Print This


Hazardous Materials Incident
What To Do during a Hazardous Materials Incident

If you suspect that there has been some type of chemical release in your area:

    - Listen to radio or TV emergency broadcasts and follow instructions given

    - Bring family and pets inside

    - Change clothes; leave old clothes and shoes outside

    - Close ALL doors and windows

    - Do not eat or drink anything uncovered

How to Shelter-in-Place

    - Bring pets and family members inside

    - Close and lock all exterior doors and windows.  Close vents, fireplace dampers and as many interior doors as possilbe.

    - Go into the pre-selected shelter room with your emergency supply kit.  This room should be above ground and have the fewest openings to the outside.

    - Seal gaps under doorways and windows with wet towels or plastic sheeting and duct tape.

    - If gas or vapors could have entered the building, take shallow breaths through a cloth or a towel.  Avoid eating and drinking any food that may be contaminated.


Tokyo ESP

東京ESP, Toukyou ESP, TokyoESP

Last chapters 72 71 70

Part 1: Urushiba Rinka was a fairly normal high school girl, though she was a bit poor and her only family was her father. Then one day, she saw a penguin and some glowing fish swimming through the sky. Rinka might have thought it was a hallucination if there hadn't been another witness with her, a boy from her school with a strangely scratched-up face. Contact with a fish caused her to pass out, and when she awoke, she had developed the power to move through inanimate objects... such as the floor of her apartment! Later, a call from her father showed her that she was not the only one the flying fish bestowed with hard-to-control superpowers! What exactly is going on here? And does Rinka's classmate know more about this situation than he's letting on? Part 2? It's now one year and four months after the battle with the professor

Manga by SEGAWA Hajime

Top Members

  • sburstalluploader
  • shadowkitshauploader
  • Lizarazuuploader

  • koryuu · 1 year ago

    did the protagonist changed

  • You have to be logged in to post comments.

Readers (95)


Finite difference time domain modeling of finite-sized electromagnetic source over periodic structure via a plane wave spectral expansion approach

[1] A novel three-dimensional time domain method is developed to study interactions between finite-sized electromagnetic sources and infinite periodic structures. The method is based on a periodic finite difference time domain method combined with the spectral expansion of electromagnetic sources. Using this method, only a single periodic cell needs to be modeled in finite difference time domain simulations. The convergence, guidelines on using the algorithm, and the acceleration scheme for the algorithm are discussed. Several periodic structures are simulated by this proposed method. It is shown that this method can significantly reduce the required computer memory and computational time.

1. Introduction

[2] Periodic structures have many electromagnetic applications ranging from frequency selective surfaces to composite meta-materials [Munk, 2000; Vardaxoglou, 1997; Ouchetto et al., 2006]. Rigorous simulations are often used to understand interactions between electromagnetic signals and these structures [Dechant and Elezzabi, 2004; Chae et al., 2004]. To take advantage of the nature of periodic structures, periodic boundary conditions have been developed and implemented in the finite difference time domain (FDTD) method [Taflove, 2000; Kao and Atkins, 1996; Roden et al., 1998; Ren et al., 1994; Marek and MacGillivray, 1993; Ko and Mittra, 1993]. However, all these implementations assume that periodic structures are illuminated by plane wave incidences. That is, these methods are only valid when the incident electromagnetic signal is a plane wave. For some applications where electromagnetic responses from finite-sized sources are required, “brute force” FDTD simulations were performed [Luo et al., 2002a, 2002b]. In the “brute force” simulations, rather than using a single periodic element, many repetitive cells were used to approximate the structure's infinite extension. Oftentimes, at least 30 unit cells are required in directions where infinite repetitions exist. However, such approximation truncates the actual structures, which could lead to significant reflections from the truncated boundary. In addition, this approach requires significantly more computer memory and CPU time compared to the modeling of a single periodic element.

[3] The purpose of this paper is to present a novel FDTD method to analyze the behaviors of arbitrary finite-sized electromagnetic sources over infinite periodic structures. Only a single periodic element needs to be modeled using this method and the field distribution at any location of the structure can be obtained. This approach not only eliminates the simulation domain truncation errors associated with the “brute-force” approach, it also leads to significant savings in both computer memory and CPU time. This approach is based on a source spectral expansion method combined with a spectral FDTD method [Cangellaris et al., 1993; Aminian and Rahmat-Samii, 2005, 2006; Yang et al., 2006; Qiang et al., 2006, 2007a, 2007b; Kokkinos et al., 2006; Li and Sarris, 2008]. In this approach, the finite-sized electromagnetic source is first expanded into its spectral components. Multiple spectral-FDTD simulations in the complex-domain are carried out using spectral electromagnetic sources. The final results obtained from multiple spectral-FDTD simulations are superposed to restore the electromagnetic signals from the original source. In addition to describing the basic principles of this technique, the guidelines of how to use this new method, which cover the convergence analysis, the selection of spectral sampling rate, and the acceleration schemes of this algorithm are also presented. Numerical examples are presented to validate this new method.

[4] The remainder of this paper is organized as follows. In section 2, the methodology of this approach is presented in detail, which includes the source expansion and the spectral-FDTD method with complex periodic boundary conditions. In section 3, some properties of this algorithm are discussed. This includes the convergence analysis, selection of appropriate spectral sampling rate, and acceleration scheme for this method. Following several numerical examples in section 4, conclusions are given in section 5.

2. Methodology

[5] Consider, as an example, the structure in Figure 1, where Px and Py are the periodicity along the x and y directions of this periodic structure. An electromagnetic current source with distribution of equation image(x, y, z, t) is located above the periodic structure. In the first step of this approach, the source is expanded into its spectral components in both the x and y directions.

Figure 1.

Illustration of the periodic structure with periodicity in both x and y directions.

2.1. Source Spectral Expansion

[6] In the source spectral expansion, the original source is expanded into a series of planar spectral sources with wave numbers of kx and ky in the x and y directions as

equation image

Here, equation image(kx, ky, z, t) is the spectral component of the original source. Each spectral component of the source is now a planar electromagnetic source, which will generate planar electromagnetic incidences. It should be noted that after the expansion, the spectral sources are complex numbers. For example, if a z-polarized electric current with a constant magnitude of I0 resides over a rectangular volume with a side length of Δx, Δy and Δz at (x0, y0, z0), a specific planar source with wave numbers of kx and ky in the spectral domain can be obtained by

equation image

where U(zz′) is a step function defined as

equation image

Using the spectral sources defined in equation (1), the original source can now be represented by a series of planar electromagnetic sources as

equation image

In practical applications, only a finite number of kx and ky can be used in the integral of equation (4). For example, for the unit electric current considered earlier, the right side of equation (4) becomes

equation image

where M and N are the number of terms to be used in the spectral expansion and kx,N/2 and ky,M/2 are the maximum values of wave numbers to be used in the spectral expansion. The choice of values for these numbers needs to be determined based on specific applications and will be discussed in the following section. Equations (4) and (5) also indicate that any arbitrary electromagnetic source can be considered as the summation of a series of planar electromagnetic sources with phase delays related to the wave numbers kx and ky in x and y directions, respectively.

2.2. Computation With FDTD Method Using Complex Periodic Boundary Conditions

[7] Since the expanded electromagnetic source includes phase delays in both x and y directions, this planar electromagnetic source can be implemented into the spectral FDTD method with the complex periodic boundary condition [Aminian and Rahmat-Samii, 2005, 2006]. In the spectral FDTD method, instead of using a split-field scheme which requires modifying the conventional FDTD equations, we can include the complex phase shifts in the field components computation in the time domain. Therefore, the periodic boundary condition applied on the electric and magnetic fields with this method becomes

equation image

The procedure of this algorithm can be described as: (1) in the main computational domain, the conventional FDTD method is used; (2) at periodic boundaries, equation (6) is used to update boundary values. Following this procedure, the dispersion relation of the conventional FDTD method is preserved. In addition, no modification in the absorbing boundary condition implementation is required. Furthermore, the time step size of this method is not related to any incident angle compared to the widely used split-field method [Roden et al., 1998; Yang et al., 2006]. Using this method, we can obtain the electromagnetic field distributions of equation image(kx, ky, z, t) due to the plane wave source of equation image(kx, ky, z, t).

[8] Once equation image(kx, ky, z, t) due to a planar source equation image(kx, ky, z, t) is obtained by a single FDTD simulation using the periodic boundary condition in equation (6), the total electric field located at (x, y, z) within a periodic cell is simply the integration of all spectral responses, given by

equation image

For an observation point that is offset m periodic cells in the x direction and n periodic cells in the y direction, the electric field can be obtained by

equation image

Therefore, once the field information within one periodic cell is known, the fields in any other periodic unit can be extrapolated directly from equation (8).

3. Numerical Properties of the Algorithm

[9] Before this algorithm is applied to analyze practical structures, the numerical properties of this algorithm are first discussed. The convergence of the algorithm, the required spectral sampling rate for practical simulations, and an acceleration scheme are discussed in this section. This is done by analyzing the electric field distribution in free space due to the radiation of an electric current as shown in Figure 2. For simplicity, the electric current used here is an infinitely long line current in the y direction. The cross-section of the current is assumed to be infinitely thin (in actual simulations, the current is assumed to be uniformly distributed in the cross-section). Since the current is infinitely long along the y direction, we can perform spectral expansion in the x direction only. In this particular simulation, the operating frequency is 3 GHz sinusoidal signal so that steady state field plot can be obtained to compare the field distribution. The assumed cubic periodic element with a side length of 1 m was used in the simulation. The infinitely long current source passes through the cubic element at the center location.

Figure 2.

Example of infinitely long electromagnetic current source.

3.1. Convergence

[10] As indicated in equation (5), in order to obtain the solution due to a finite electromagnetic source over an infinite periodic structure, one needs to determine the maximum values for wave numbers to be used in each expansion direction. For the example here, we will only discuss the maximum value of the wave number to be used in the x direction and its limit is selected from −100 rad/m to 100 rad/m. Furthermore, we set dkx equal to 1 rad/m and the current strength as 1 A. Figure 3 shows the sampled electric fields obtained by the analytical solution and by the proposed approach along the AA′ and BB′ lines as indicated in Figure 2. If the center of the cubic element (with the current source) is located at (0,0,0) m, the two coordinates for the AA′ line are (0,0,0) m and (0.5, 0,0) m. BB′ line is defined as the duplicate of AA′ line that is shifted −1 m in the z direction. As a result, AA′ corresponds to the electric field along a line perpendicular to the current source while BB′ corresponds to the line that is offset by one unit of the AA′ line along the z direction as shown in Figure 2. As we can see from Figure 2, when these parameters are used in the simulations, a good agreement between the analytical solution and the numerical approach is obtained.

Figure 3.

Comparison between the results obtained by the FDTD method and the proposed approach due to an infinitely long electromagnetic current source.

[11] To understand the effects of the convergence of this algorithm, we show a normalized error as a function of distance from the line source and the maximum value of kx used in the integral of equation (7) or (8). The error is defined as the

equation image

[12] Figure 4a shows the error function defined in equation (9). The error bar on the right side clearly indicates that as the observation point gets closer to the source, a larger number of spectral expansion terms should be used in order to obtain accurate solution. In addition, for any distance away from the source, the error generally decreases as the maximum value of kx increases. However, for an observation point more than 0.05 m (which is equivalent to half of a wavelength) away from the source, increasing the maximum value beyond 63 rad/m for kx does not lead to significant error reduction. This maximum value of 63 rad/m is determined by ωequation image. When kx has a value that is larger than the frees pace wave number, the plane wave will have exponential decay in the z direction. Such evanescent behavior will not given further error reduction if the observation point is far away from the source. This indicates that to evaluate propagating waves in far field region, the maximum value of kx in the expansion can be approximately obtained by ωequation image. However, for near field calculation, larger spectral values are needed to represent the near field evanescent wave behavior. To further investigate the this error plot, Figure 4b shows the normalized error in logarithmic scale along three lines that is 0.01 m, 0.21 m, and 0.41 m away from the source. As we can see from Figure 4b, for the two observation points that are relative far away from the source, increasing the maximum value of kx beyond 63 rad/m does not significantly reduce the normalized error, since most evanescent waves cannot propagate that far. However, for the observation point that is closer to the source, even when maximum value of kx reaches 100 rad/m, the normalized error is still around −30 dB. To further reduce this error, more terms maybe necessary dependent on the required numerical accuracy.

Figure 4.

(a) Error as a function of distance away from the source and the maximum spectral value required in the simulation. (b) Error as a function of maximum sampling value at different observation locations.

3.2. Spectral Sampling Rate

[13] In the previous analysis, we used a fixed spectral domain sampling rate of 1 rad/m in the convergence analysis. In this section, we briefly discussed the effect of spectral sampling rate on the time domain simulation results. Here, the line source emitted a modulated-Gaussian pulse. For the purpose of comparison, conventional FDTD simulations were also carried out. Figure 5 shows the comparison between the time domain signals generated by the FDTD method and this proposed approach. The observation point here is 0.05 m away from the line source in the x direction. For this simulation, we used the maximum value of 100 rad/m for kx and a sampling rate of 1 rad/m. As we can see from Figure 5, the results of these two approaches agree well with each other up to 20 ns. In Figure 6, we show the time domain wave form when we reduce the spectral sampling rate from 1 rad/m to 3 rad/m. Initially, the result obtained by this approach agrees well with the FDTD approach, but a spurious waveform occurs at the time instance around 10 ns. If we further reduce the sampling rate to 5 rad/m, we observed that the spurious waveform will be even closer to the original waveform. The appearance of the spurious waveform can be explained by the sampling theorem. According to the sampling theorem, the aliasing will occur when the spectral sampling rate is not sufficient. In our algorithm, aliasing appears as image sources located at 2πk away from the original sources (Δk is the spectral sampling rate). Therefore, for large value of Δk, the image sources will be close to the actual electromagnetic source causing errors in FDTD results. Consequently, for accurate simulations, a sufficiently large sampling rate shall be used to guarantee the non-aliasing effect.

Figure 5.

Comparison between the time domain waveforms generated by the FDTD method and the proposed method with a spectral sampling rate of 1 rad/m.

Figure 6.

Comparison between the time domain waveforms generated by the FDTD method and the proposed method with a spectral sampling rate of 3 rad/m.

3.3. Acceleration Scheme

[14] In section 2, we indicate that we need to perform spectral sampling for kx and ky from −∞ to ∞. Spectral FDTD simulation should be carried out at every (kx, ky) pair because different kx and ky require different boundary conditions as indicated in equation (6). However, also indicated in equation (6), if we have two different values of kx1 and kx2, and they are related by kx2 = kx1 + 2πn/Px, where n is an arbitrary integer, then both kx1 and kx2 will satisfy equation (6). In other words, if two spectral plane waves whose horizontal wave number kx are offset by the multiples of 2π/Px, both will satisfy the boundary condition described in equation (6).

[15] Since both of them satisfy the same boundary condition, we can launch two excitations simultaneously in spectral FDTD simulations. In light of this, we can launch multiple plane waves during a single spectral FDTD simulation provided their horizontal wave numbers are offset by multiples of 2π/Px in the x direction and multiples of 2π/Py in the y direction.

[16] If we assume that the finite-sized electromagnetic source is a source located at (x0, y0) and its variation in the z direction is described by Z(z), we can write this in the form of

equation image

Following the Fourier series expansion of impulse functions in two-dimensional spatial domain,

equation image

we have

equation image

This is equivalent to

equation image

equation image

Equation (14) indicates that including all kx terms that are offset by multiples of 2π/px in a single simulation can be considered as a different way to perform the source expansion. Rather than performing the planar spectral source expansion, we can also expand the source in terms of the periodic source arrays corresponding to different wave number modes kx and ky. Effectively, approach is similar to the array-scanning-method (ASM) [Munk and Burrell, 1979; Qiang et al., 2007b; Li and Sarris, 2008]. However, it should be pointed out that the convergence and sampling rate criteria of ASM and plane wave expansion approaches can be significantly different due to adding more spectral sources into a single spectral FDTD simulation.

4. Numerical Examples

[17] To demonstrate the effectiveness of our proposed method, two numerical demonstrations are given below.

[18] The first example considered here is a single horizontal electric dipole over the center of an infinite microstrip patch array shown in Figure 7. The periodicity in both directions are given by a = 15 mm and b = 15 mm. The length (l) of the strip is 12 mm and the width (w) of the strip is 3 mm. The microstrip patch array resides on a perfect electric conductor (PEC) backed dielectric substrate whose relative dielectric constant is 4. The thickness (h) of the substrate is 5 mm. The dipole source is operating at 9 GHz and polarized in the z direction. It is located 15 mm above the center point of one of the conductor metal strip.

Figure 7.

Top and side views of the patch structure to be analyzed.

[19] Both the conventional FDTD simulation and the proposed method were used to obtain the electric near field distribution in the vicinity of the microstrip. For the conventional FDTD simulation, 21 unit elements in both directions are required. However, using the proposed approach, only a single unit element needs to be modeled. Figure 8 shows the electric field (z component) distribution at the top of the microstrip array structure. Simulation results from the FDTD simulation were also given for comparison. As we can clearly see from Figure 8, the results obtained by these two approaches agree well with each other in the center regions of this structure. The discrepancy between the FDTD method and the proposed approach near the edges of the structure is caused by reflection due to the structural truncation in the FDTD simulations. Again, we would like to point out that using the proposed approach, the required computer memory is less than 0.5% of that required by the conventional FDTD method. With such reduction in the memory requirement, it is possible to use this method to investigate many periodic structures where extremely fine mesh is required in the discretization.

Figure 8.

Comparisons between the electric field distributions along the microstrip arrays by the FDTD method and the proposed approach. (top) Electric field distribution along the z direction on top of the patch strip. (bottom) Zoomed view of the electric field distribution of Figure 8 (top).

[20] The second example exhibited here is a periodic dipole array with 81 × 81 elements (to approximate infinitely large array) shown in Figure 9. Each element includes a thin wire antenna with a length of 27 mm (λ/2) and its operating frequencyis at 5.55 GHz. The center spacing between dipole antennas are 45mm and 30mm in the x and y directions, respectively. In the simulation, FDTD method used a mesh size of 3 mm in all x, y and z directions.

Figure 9.

An illustration of a dipole array antenna (81 × 81 elements). (a) View of unit element. (b) View of excited array area (21 × 21 elements).

[21] Unlike previous example in which there is only one excitation source, this array structure is driven by multiple source, e.g., in a 21 × 21 active region as indicated in Figure 9b. Outside this region, antenna elements are passive although they can also affect the antenna pattern due to mutual coupling. Two different types of excitation sources are used in the example. In the first case, each antenna in the active region is fed by an identical source at 5.55 GHz. In the second case, excitation sources are uniform in the z direction and have a linear roof-top variation in the x direction.

[22] Using this proposed algorithm, all excitation sources in the active region can be expanded and lumped together into spectral FDTD simulations. Both near field and far field generated by different feedings can be evaluated with simulations performed in a single unit element. Here, only the far field radiation patterns are used as shown in Figure 10. As indicated in Figure 10, the results obtained by this proposed approach agree well with the conventional FDTD method. In addition to using only single unit element in the simulation, we also observed a reduction in CPU time for this particular example. To obtain the results as shown in Figure 10, the proposed method only takes about 0.5 hour on regular CPUs. However the conventional FDTD method requires 10 hours of CPU time on the same PC to analyze the 81 × 81 elements. More importantly, the FDTD simulation already reaches the memory limit on a 32-bits machine and it cannot be used to model larger structures (for example, the 100 × 100 elements array).

Figure 10.

Radiation patterns calculated by the proposed method and the conventional FDTD method with different type of excitations. (a) Uniform excitation within active region. (b) Roof-top excitation within active region.

5. Conclusion

[23] A novel method is proposed for the analysis of the interaction between finite-sized electromagnetic source and infinite periodic structures. The method is based on combining the source spectral expansion with a spectral FDTD method. Some properties of this proposed algorithm are presented in the paper. Several numerical examples are used to demonstrate the effectiveness of the proposed approach. It is observed that this proposed method can reduce the required computer memory by a factor over 100 in most applications.


DaGeneral enjoys rocking dance floors all over Europe as a B Se-Lek tive resident.  On the production front  DaGeneral has had various tracks signed on some prolific labels across the globe including Se-Lek Music, Alchemy, Layer 909, and has also remixed tracks for Blue Amazon, Jon The Dentist, amongst others.  Gaining support from artists such as Skober, Lisa Lashes, Jam El Mar, Arjun Vagale, Anthony Pappa, Phutek, SLAM and many more!


When it comes to ensuring the future health of a newborn, a lot of emphasis is placed on the mother’s lifestyle – as numerous studies have found that a mother’s weight and diet can heavily influence a fetus’s development in the womb.

But it may not just be mom’s eating habits that can affect an unborn child. New research from McGill University in Montreal has revealed that a father’s diet pre-conception may also play a crucial role in the future health of his offspring.

“We know the father contributes half the heritable information, so the potential is there to have an enormous impact on the development of offspring,” lead author Dr. Sarah Kimmins, Canada research chair in epigenetics, reproduction and development at McGill, told FoxNews.com.   “But the research is all targeted at the mother. If you look at national sites, their phrasing is, ‘Women need to do the following preconception.’  Not a single word is there of the father.”

In their study, Kimmins and her colleagues highlighted the significance of the vitamin B9 – also known as folate – which is found naturally in a number of leafy vegetables, fruits, cereals and meats.  Previous research has indicated that mothers must get an adequate amount of folate in their diets in order to prevent birth defects and miscarriages.

However, the relevance of a father’s folate intake has gone unstudied.

“Folate functions in this biochemical pathway in the body, where it serves in basically donating these biochemical tags.  [These] are placed on the DNA in the genome that control whether a gene is on or off,” Kimmins said. “So if you don’t have enough folate, you don’t have enough of these biological tags.  So the embryo may not turn on the genes it should.”

Folate-deficient diets are typically found in countries experiencing food insecurity, as people in those regions lack adequate access to nutritional foods.  Additionally, folate-deficient diets can also be said to mimic the diets of people who are overweight or obese, since their bodies often cannot process folate properly.

To better understand how a father’s diet and folate intake might impact a child’s health, the researchers examined the offspring of a group of male mice.  Before the mice procreated, half of the fathers received a diet deficient in folate and the other half received a diet with adequate levels of the vitamin.

The researchers found that the offspring of the folate-deficient fathers had a 30 percent increased risk of birth defects, compared to the offspring of the fathers who had received a sufficient amount of folate.  They also found that the folate-deficient mice experienced some symptoms of infertility and were less likely to impregnate the female mice.

Kimmins said these findings suggest that a father’s lifestyle may alter his sperms’ epigenome, which can ultimately transfer faulty information to the so-called epigenomic map that influences the development of disease in the long-term health of his offspring

“People have really been focused on what happens in the womb and where birth defects originate,” Kimmins said. “….You see most birth defects happen in the first three months of developments, but the causes of over 50 percent of birth defects are not known.  [They] very well could be originating pre-conception.”

Though the researchers still need to verify their findings in humans, Kimmins hopes the study will inspire men to pay more attention to what they’re eating if they are considering having children.  She noted that men can potentially reverse the damage done to their sperm simply by switching to a healthier diet a few months before conception.

“There should be a paradigm shift,” Kimmins said. “Men are not just responsible for their own health.  They’re also responsible for the health of their offspring.  I think this warrants a much closer look, because it’s a very quick route to intervention and prevention.”

The research was published in the journal Nature Communications.


Neo-Tethys Sea

Ancient sea
Alternate Titles: Neo-Tethys Ocean, New Tethys Sea

Learn about this topic in these articles:

development during

Cenozoic Era

...and Arctic oceans. The Atlantic continued to expand while the Pacific experienced a net reduction in size as a result of continued seafloor spreading. The equatorially situated east–west Tethyan seaway linking the Atlantic and Pacific oceans was modified significantly in the east during the middle Eocene—about 45 million years ago—by the junction of India with Eurasia,...

Oligocene Epoch

...prevailed. This cycle of marine transgression, followed by the establishment of brackish and then freshwater environments, was repeated during the Oligocene. Sediments on the floor of the ancient Tethyan Sea, which covered part of Eurasia during the Oligocene, were deformed early in the development of the European Alps.

Permian Period

...the Earth’s continents and in the evolution of life. The principal geographic features of the Permian world were a supercontinent, Pangea, and a huge ocean basin, Panthalassa, with its branch, the Tethys Sea (a large indentation in the tropical eastern side of Pangea).

Triassic Period

geologic history of

Alpine-Himalayan System

While the Cimmerian continent was drifting northward, a new ocean, the Neo-Tethys, was opening behind it and north of the Gondwanaland supercontinent. The new ocean began closing some 155 million years ago, shortly after the beginning of the major disintegration of Gondwanaland. Two fragments of Gondwanaland, India and Arabia, collided with the rest of Asia during the Eocene (i.e.,...

Black Sea

The geologic history of the Black Sea is not fully known, but it seems to be a residual basin of the ancient Tethys Sea, dating roughly from 250 to 50 million years ago. The present form of the sea probably emerged at the end of the Paleocene Epoch (about 55 million years ago), when structural upheavals in Anatolia split off the Caspian basin from the Mediterranean. The newly...

...that lasted hundreds of millions of years. Formation of the belts gave rise to the supercontinent of Pangea; its fragmentation, beginning about 200 million years ago, gave rise to a new ocean, the Tethys Sea. Closure of that ocean about 50 million years ago, by subduction and plate-tectonic processes, led to the Alpine orogeny—e.g., the formation of the Alpine orogenic system, which...
During the Mesozoic Era the Tethys Sea evolved in what is now southern Europe, and during the Cenozoic Era that ocean was destroyed by subduction as many small plates collided. Those events gave rise to the present-day tectonic mosaic that extends eastward from the Atlas Mountains of North Africa, the Baetic Cordillera of southern Spain, and the Pyrenees via the Alps of maritime France,...

During the Jurassic Period (about 201 to 145 million years ago), a deep crustal downwarp—the Tethys Ocean—bordered the entire southern fringe of Eurasia, then excluding the Arabian Peninsula and the Indian subcontinent. About 180 million years ago, the old supercontinent of Gondwana (or Gondwanaland) began to break up. One of Gondwana’s fragments, the lithospheric...

Mediterranean Sea

Until the 1960s the Mediterranean was thought to be the main existing remnant of the Tethys Sea, which formerly girdled the Eastern Hemisphere. Studies employing the theory of seafloor spreading that have been undertaken since the late 20th century, however, have suggested that the present Mediterranean seafloor is not part of the older (200 million years) Tethys floor. The structure and...

ocean basins

...all the present-day continents. Since that time the major developments have included a shrinking of the Pacific basin at the expense of the growing Atlantic and Arctic basins, the opening of the Tethys seaway circling the globe in tropical latitudes and its subsequent closing, and the opening of the Southern Ocean as the southern continents moved north away from Antarctica.

Tethys equatorial ocean

The Neo (New, or Younger) Tethys Sea, commonly referred to simply as Tethys or the Tethys Sea, began forming in the wake of the rotating Cimmerian continent during the earliest part of the Mesozoic Era. During the Jurassic the breakup of Pangea into Laurasia to the north and Gondwana to the south resulted in a gradual opening of Tethys into a dominant marine seaway of the Mesozoic. A large...

study of continental collision

...collisions are usually preceded by a long history of subduction and terrane accretion, many mountain belts record all three processes. Over the past 70 million years the subduction of the Neo-Tethys Sea, a wedge-shaped body of water that was located between Gondwana and Laurasia, led to the accretion of terranes along the margins of Laurasia, followed by continental collisions...
Neo-Tethys Sea
print bookmark mail_outline
  • MLA
  • APA
  • Harvard
  • Chicago
You have successfully emailed this.
Error when sending the email. Try again later.
Email this page


Faculty: Overview

Through the application process, students must prepare a cover letter, resume, reference page, complete additional requirements and have a personal interview with the prospective business.  Students, if selected for an internship, are required to spend a minimum of 150 hours on the job.  The internship experience is a partnership among the student, faculty advisor, and business practitioner.  Assurance of learning is facilitated through evaluations submitted by the student, faculty advisor, and business practitioner.  Through an analysis of evaluations and review of the overall internship process, the program strives to assure a quality experience for all participants.

The faculty advisor's responsibilities include the following:

  • Provide a course syllabus for the internship experience.
  • Provide a learning objective agreement for the internship experience.


Will.I.Am was allowed into Paris’s Louvre museum at two in the morning to record part of a song entitled “Smile Mona Lisa” in front of the famed painting by Leonardo da Vinci, he told reporters in Paris on Wednesday.

“That song touches me because I recorded a large portion of that song inside the Louvre, next to Mona Lisa’s picture,” the lead singer of the Black Eyed Peas said, adding that the song would appear on his next solo album.

“They let me go to the Louvre at 2 am to record the guitars for that song, I wWill.I.Am records Mona Lisa song in Louvreanted to capture the ambiance of the Louvre, that Mona Lisa lives in. That was exciting, to walk through the Louvre at 2 am with the manager,” he said.

“I’m fascinated with quantum physics. That’s the reason why I’m going back to school this September to learn computer science,” he said.


Register Now

Lost Password

Register Now

To determine the final setting time of cement. This test is required to understand the rate of gain of strength of cement w.r.t. to time.

Vicat apparatus, needle for initial setting time, stop watch.

Place the test block and the non porous plate under the rod bearing the needle with the annular attachment for final setting time. Lower the needle gently till the needle makes an impression there on, while the attachment fails to do so. In the beginning the needle will completely pierce the block. Repeat the procedure. The period elapsing between the time when water is added to the cement and the time at which the needle fails to make an impression on the surface of the test block shall be the final setting time.

The final setting time of the given sample of cement =……………..min

Now ask any questions to Civil Engineers around the world.

Ask question