acceptable toxicity levelsearch for term
active ingredientsearch for term
The specific chemical in a formulation that is responsible for killing or controlling a plant.
acute effectsearch for term
acute exposuresearch for term
A single or short-term exposure to a chemical that results in severe harm or death.
adsorbingsearch for term
To take up and hold by adsorption.
adsorptionsearch for term
The attachment of a thin layer of molecules (as of gasses, solutes, or liquids) to the surfaces of solids or liquids with which they are in contact.
adventivesearch for term
Arrived in the geographical area specified from somewhere else by any means (adjective); not native (non-indigenous) to the area in which it has arrived.
adventive biological controlsearch for term
Regulation of a pest population by a natural enemy that has arrived from elsewhere without deliberate introduction.
algae bloom (algal bloom) (bloom)search for term
When chlorophyll concentrations reach a level over 40 micrograms per liter, forming mats or clumps of algae.
alkalinesearch for term
Basic, having a pH of more than 7.
anadromoussearch for term
A fish that migrates from the sea to freshwater.
anoxiasearch for term
A hypoxia of extreme severity as to result in permanent damage.
apical meristemsearch for term
The portion of a plant, located at end of a root or shoot that is responsible for increase in length.
application ratesearch for term
aquaculturesearch for term
The cultivation of animals and plant life in a water environment. Florida is one of the national leaders in aquaculture, producing large quantities of aquatic plants, fish and animals for commercial sale. Many of the aquaculture crops in Florida are not traditional food species, but specialty items such as tropical fish and ornamental aquatic plants.
aquascapingsearch for term
The practice of using aquatic and wetland plants to landscape in and around water. It is mainly for the purpose of visual enhancement, but can also attract wildlife including waterbirds. In Florida, many retention and stormwater management ponds are aquascaped to help mitigate for lost wetland habitat. Aquascaping helps filter pollutants from runoff and safeguard water quality.
aquatic macrophytesearch for term
Aquatic plants that are large enough to be visable to the naked eye.
aquifersearch for term
A formation, group of formations, or part of a formation that contains or conducts groundwater. Especially one that supplies water for wells and springs.
atmospheric nitrogensearch for term
Nitrogen in gaseous state.
augmentative biological controlsearch for term
Release of large numbers of a biological control agent to supplement small numbers already present, in expectation of a greatly increased effect.
bedrocksearch for term
The solid rock underlying unconsolidated surface materials (such as soil).
benthicsearch for term
Of, relating to, or occurring on the bottom underlying a body of water.
bioaccumulatesearch for term
The accumulation of a substance (as a pesticide) in a living organism.
bioavailabilitysearch for term
The degree and rate at which a substance is absorbed into a living system or is made available at the site of physiological activity.
biodiversitysearch for term
A number of species growing in balance within an ecosystem.
biological controlsearch for term
The purposeful introduction of natural enemies by scientists and environmental managers as a means to weaken and suppress invading plants.
biological productivitysearch for term
The ability of a waterbody (or habitat) to support plants, fish, and wildlife. The rate at which organic material is produced.
biomasssearch for term
Weight of all living material in a unit area at an instantaneous time.
bloomsearch for term
A rapid and excessive growth of a plankton population.
brackishsearch for term
Somewhat salty.
brand namesearch for term
Name under which the manufacturer sells the product.
breakdown pathwaysearch for term
The environmental processes that cause a herbicide to no longer be toxic to plants.
broad spectrum herbicidesearch for term
A herbicide that kills a wide range of plants.
calcareoussearch for term
Resembling calcite or calcium carbonate, especially in hardness. Growing on limestone or in soil with lime.
cationicsearch for term
Relating to a positively charged ion.
cautionsearch for term
certified applicatorsearch for term
chemical namesearch for term
chlorophyllsearch for term
Green, light-absorbing molecules inside the chloroplasts of algae and green plants.
chloroplastssearch for term
Chlorophyll-containing plastids found in algal and green plant cells.
cholorophyllsearch for term
The green photosynthetic pigment found chiefly within plants.
chronic exposuresearch for term
Repeated low level exposures over an extended period of time. Aside from mortality, health effects can be reported in terms of reproductive harm and cancer risk.
colorsearch for term
Refers to the presence of dissolved organic materials (humic acids from decaying leaves) and also dissolved minerals, which can give water a reddish-brown or “tea” color. In some cases, these substances can make the water appear almost black.
common namesearch for term
The recognized, nonscientific name given to pesticides.
contact herbicidesearch for term
A herbicide that causes injury to plant tissue where contact occurs.
contact timesearch for term
Duration of herbicide exposure to the plant.
contaminantssearch for term
Substances that potentially threaten water quality such as; human and animal bacteria, pesticides, fertilizers, fuel spills, and other pollutants.
convectional mixingsearch for term
mixing of water due to changes in temperature (e.g., surface water cools and sinks at night). Water is constantly moving and mixing even on days with no wind.
dangersearch for term
dermal exposuresearch for term
Contact with skin.
detritalsearch for term
Loose material (such as rock fragments or organic particles) that results directly from disintegration.
diffusionsearch for term
To extend freely (extend, scatter). Dissolved substances moving from a region of higher to lower concentration.
directions for usesearch for term
dissipationsearch for term
The slow reduction in concentration and eventual loss of a substance through degradation, dilution, or both processes.
dissolved oxygensearch for term
Oxygen gas that is dissolved in water. Fish need oxygen just as land animals do.
dosesearch for term
The quantity of chemical exposure per unit of time.
drawdownsearch for term
Also called drydown or dewatering, reduction of water body level to control exposed plants and improve substrate to support plant diversity.
ecological nichessearch for term
A habitat supplying the factors necessary for the existance of an organism or species. The ecological role of an organism in a community especially in regard to food consumption.
efficacysearch for term
emergentsearch for term
Rooted in shallow water and having most of the vegetative growth above the water.
emersedsearch for term
Rooted in shallow water and having most of the vegetative growth above the water. Synonymous with emergent.
epilimnionsearch for term
A surface layer of water overlaying the thermocline of a lake.
eradication search for term
To do away with completely. To thoroughly exterminate and remove.
establishment numbersearch for term
euphotic zonesearch for term
Zone where there is sufficient light for the growth of plants.
eutrophicsearch for term
Enriched in dissolved nutrients.
eutrophicationsearch for term
The process by which a body of water becomes enriched in dissolved nutrients (as phosphates) that stimulate the growth of aquatic plant life usually resulting in the depletion of dissolved oxygen.
evaporationsearch for term
The process by which water vaporizes and escapes from water surface, rising into the atmosphere. Evaporation rates are affected by latitude of the water body (solar energy input), air and water temperatures, air pressure, wind velocity over the water surface, and turbulence in the water. Evaporation rates are also influenced by the plant coverage on the lake’s surface. In general, evaporation decreases as emersed plant and floating plant coverage increases. Floating-leaved plants can however reduce the evaporation loss of water in a lake.
evapotranspirationsearch for term
The process by which water vapor is taken up and used by plants, and transpired (emitted as water vapor) to the atmosphere. In most situations, aquatic macrophyte evapotranspiration greatly increases water loss from a water body. Evapotranspiration rates depend on plant characteristics such as height and leaf area index as well as environmental factors such as latitude, air and water temperatures, wind speed, relative humidity, plant growth phase and nutrient availability.
exposuresearch for term
Route of entry into the body (dermal, inhalation, or ingestion).
fire regimesearch for term
The pattern, frequency, and intensity of wildfires and brushfires that prevails in an area.
floating islandssearch for term
Floating rafts from a few inches to several feet thick of peat or muck supporting aquatic, herbaceous and woody plants, and sometimes trees.
floating-leavedsearch for term
A plant that may or may not be anchored to the sediment, but has leaves that float on the surface of the water.
flocculentsearch for term
Having a fluffly or wooly appearance.
Floridan aquifersearch for term
The portion of the principal artesian aquifer that Extends into Florida. The principal artesian aquifer is the largest, oldest and deepest aquifer in the southeastern U.S. It is contained under pressure by a confining bed of impermeable sediments. In areas of great enough pressure, spring flows are produced.
fluvialsearch for term
Of, relating to, or living in a stream or a river. Or produced by the action of a stream or river.
formulationsearch for term
The form in which a herbicide is sold (liquid, granular or other form), or a mixture of active and inert ingredients combined during product manufacture. Synonyms: formulations
fortuitous biological controlsearch for term
free-floatingsearch for term
A plant that is not anchored in the sediment; they get their nutirents directly from the water.
frysearch for term
Young or recently hatched fish.
graminoidsearch for term
Of or resembling the grasses.
gravidsearch for term
Carrying developing young or eggs.
half-lifesearch for term
The half-life of a herbicide describes the length of time it takes for 50% of the herbicide to break down to secondary compounds.
herbaceoussearch for term
Having little or no woody tissue.
herbicidesearch for term
A chemical substance used to destroy or inhibit the growth of plants, especially weeds.
herbicide precipitationsearch for term
Falling out of solution and sinking to the bottom.
herbivoroussearch for term
humic acidsearch for term
Produced when organic matter such as dead leaves and plant material decay. Humic acids can color water so that it appears reddish or reddish-brown, even black.
hydraulic conductivitysearch for term
Ability of a canal to transport water. Water-handling capacity.
hydraulic gradientsearch for term
The movement of water downward along the horizontal slope of the subsurface bedding plane.
hydrologic cyclesearch for term
The sequence of conditions through which water passes from vapor in the atmosphere through precipitation on land and water surfaces and then back to the atmosphere through evaporation and transpiration.
hydrolysissearch for term
Breaking down in water.
hydrostatic headsearch for term
A measure of water pressure. The pressure at a given point in a liquid measured in terms of the vertical height of a column of the liquid needed to produce the same pressure.
hypereutrophicsearch for term
An aquatic system with high productivity and very high nutrients.
hypolimnionsearch for term
the part of a lake below the thermocline made of water that is stagnant and of essentially uniform temperature except during the period of overturn.
hypoxiasearch for term
A deficiency of oxygen.
inactivationsearch for term
Herbicide broken down.
inertsearch for term
Lacking a usual or anticipated chemical or biological action.
inert ingredientssearch for term
inhalationsearch for term
Inhaling or breathing in a substance.
inundative biological controlsearch for term
Release of large numbers of a biological control agent relative to the numbers of a target species, in expectation of a rapid effect. There is no implication that the released biological control agent will establish a permanent population.
karstsearch for term
An irregular limestone region with sinkholes, underground streams, and caverns.
labelingsearch for term
LD50search for term
Dose lethal to 50% of a test population (typically used for lab rats receiving the herbicide orally or in other ways).
lethal plant dosesearch for term
The amount of herbicidal actvie ingredient that is required to kill a plant.
ligninssearch for term
Substances related to cellulose that occur in the woody cell walls of plants and in the cementing material between them.
limnologistsearch for term
A Scientist that studies lakes and other freshwater bodies including their physical, chemical, and biological characteristics.
littoral zonesearch for term
The zone of water closest to the shore where light reaches all the way to the bottom.
magnesiumsearch for term
A common component of water and an essential nutrient for all organisms including vegetables, algae, fish and mammals. It is represented in the Periodic Table as Mg.
marlsearch for term
A loose or crumbling earthy deposit (of sand, silt, or clay) that contains a substantial amount of calcium carbonate.
maximum use rate search for term
The target amount of herbicide in the water after application.
metabolitessearch for term
Products, such as amino acids and nucleotides, that are formed as a result of the chemical reactions that happen during the cellular process, metabolism.
metalimnionsearch for term
The stratum below the epilimnion and hypolimnion water layers.
microbialsearch for term
Broken down by microbes.
migratorysearch for term
To move from one place to another.
miltsearch for term
The sperm-containing fluid of a male fish.
monoculturesearch for term
Population of low or single-species diversity.
narrow-spectrum herbicidesearch for term
A herbicide that targets a specific plant species.
ninety-six hour LC50search for term
nitrogensearch for term
nitrogen fixationsearch for term
non-classical biological controlsearch for term
nutrientssearch for term
oligotrophicsearch for term
An aquatic sytem that contains low concentrations of nutrients. Biologically less productive, supporting small amounts of algae, few plants and fish. Water is clear.
oral exposuresearch for term
oxidesearch for term
Binary compound of oxygen and another element (Example – iron oxide).
oxidizesearch for term
To expose to air, oxygen.
PDMPsearch for term
Pesticide Discharge Management Plan – demonstrates integrated pest management strategies and documents steps taken to reduce pesticide discharges to water of the U.S.
peatsearch for term
Partially carbonized vegetative tissue formed by the partial decomposition in water of various plants.
periphytonsearch for term
Organisms (such as some algae) that live attached to underwater surfaces.
personal protective equipment (PPE)search for term
phosphoroussearch for term
A nonmetallic element that occurs widely especially as phosphate fertilizers.
photic zonesearch for term
The layer of a body of water penetrated by sufficient sunlight for photosynthesis.
photolysissearch for term
Breaking down in sunlight. Synonyms: photodegradation
phytotoxicsearch for term
Poisonous to plants.
pioneeringsearch for term
To open or prepare for others to follow. The first instance of a plant species.
planktonsearch for term
The floating organisms occurring in a body of water, primarily made of microscopic algae and protozoa.
pneumataphoressearch for term
A submerged or exposed root often functioning as a respiratory organ in swamp or marsh plants (Example: a cypress knee).
potable watersearch for term
Water which is fit for consumption for humans and other animals. Drinking water.
ppbsearch for term
Parts per billion.
precipitationsearch for term
Falling out of solution and sinking to the bottom.
prescribed firesearch for term
Fire applied in a knowledgeable manner to vegetative fuels on a specific land area under selected weather conditions to accomplish predetermined, well-defined management objectives.
propagulesearch for term
Vegetative or sexual structures with the ability to create new plants; examples include turions, tubers, bulblets, fragments, winter buds and seeds.
rechargesearch for term
Replenishment of the aquifer by groundwater.
registration numbersearch for term
restricted-use pesticidesearch for term
rhizoidssearch for term
A rootlike structure.
rinsatesearch for term
saturatesearch for term
Secchi depthsearch for term
The depth at which a Secchi disk dropped into the water disappears from sight. A measurement of water clarity.
Secchi disksearch for term
A black and white disk attached to a rope which is used to measure water clarity. The depth at which it disappears from view when dropped into the water is the Secchi depth.
Secchi transparencysearch for term
A small black and white disk called a Secchi disk is dropped into the water, and where it disappears from view is called the Secchi transparency or the Secchi disk depth.
selectivitysearch for term
Ability of a herbicide to kill certain types of plants without causing significant injury to others.
senescesearch for term
To reach later maturity, to grow old.
signal wordsearch for term
standing cropsearch for term
amount of existing plant material present
statement of practical treatmentsearch for term
submersedsearch for term
substratesearch for term
An underlying layer, the base over which an organism lives or which it moves.
surficial aquiferssearch for term
Shallow beds of shells and sand that lie less than 100 feet underground, separated from the Floridian aquifer by a confining bed of soil. Groundwater continuously moves along the hydraulic gradient from areas of recharge to areas of discharge.
systemic herbicidesearch for term
A herbicide that is absorbed into the plant through the leaves, stems or roots and translocated throughout the plant to kill it from the inside. Slower acting than contact herbicides.
tanninsearch for term
A dissolved substance from organic matter that imparts a red or brown stain to the water.
temperature inversionsearch for term
An increase of temperature with height through a layer of air.
thermal stratificationsearch for term
The horizontal layering of differing densities produced in a lake by temperature changes at different depths.
thermoclinesearch for term
Transition zone in a thermally stratified body of water between upper surface water (epilimnion) and deeper water (hypolimnion). Lack of water circulation causes temporary stratification, with the thermocline existing in the middle layer of water.
toxicitysearch for term
The degree or extent that a chemical or substance is poisonous.
transformationsearch for term
The environmental processes that cause a herbicide to no longer be toxic to plants, including adsorption (binding to the soil).
translocatesearch for term
The conduction of a soluble material (as metabolic products) from one part of a plant to another.
transpirationsearch for term
triploid grass carpsearch for term
Carp having three sets of chromosomes (triploid) instead of the normal two sets of chromosomes (diploid), making them sterile.
troglobitessearch for term
True cave-dwelling organisms that cannot survive on the surface. These organisms rely on consistent water temperature and quality for survival. Many of these in Florida are arthropods and are threatened or of special concern.
trophic statesearch for term
Also known as trophic status. The degree of nutrient enrichment of the water.
tuberssearch for term
turbidsearch for term
Murky due to suspended sediment or other particles in the water (stirred up). Synonyms: turbidity
turionsearch for term
A compacted vegetative bud produced along the stem that can overwinter and form a new plant.
tussockssearch for term
Floating rafts of herbaceous vegetation.
vascular plantssearch for term
Plants that have tissue systems responsible for carrying or circulating fluids, such as sap and/or water throughout the body of a plant.
viscositysearch for term
Resistance to flow in a fluid or semifluid.
warningsearch for term
water claritysearch for term
The degree to which water is free from particles and easily seen through; the clearness or transparency of water.
water columnsearch for term
A conceptual column of water from lake surface to bottom sediments.
water transparencysearch for term
The amount of light penetrating into the water column.
water-tablesearch for term
watershedsearch for term
The area that drains into a river or a lake (separated by a dividing ridge such as a mountain range).


All posts in Research Basics

Computerized tomography (CT)^

How CT works^

Advantages and Disadvantages of CT^

CT and Huntington’s disease^

Functional Magnetic Resonance Imaging (fMRI)^

Public domain, NASA

An fMRI scan of a human brain. (Public domain)

How MRI works^

Advantages and Disadvantages of fMRI and MRI^

fMRI and Huntington’s Disease^

Positron Emission Tomography (PET)^

How PET works^

Advantages and Disadvantages of PET^

PET and Huntington’s disease^

Works Cited^

Further Reading^

FAQ about getting CT scans

A more detailed explanation of how MRI works
Additional information about fMRI

FAQ about getting PET/CT scans

J. Nguyen 4.9.12

Clinical Trials on Huntington's disease

What are clinical trials?

What are the different types of clinical trials?^

Clinical trials are conducted in phases.

What is the Huntington Study Group?^

Ongoing Studies that are Currently Enrolling Participants^

Ongoing Studies that are No Longer Enrolling Participants^

Recently Completed Clinical Trials^

For more information:^

-A. Zhang, 7-5-11 More

Studying Huntington's Disease

Fig Y-1: Transgenic Mouse Paw

Animal Research^

  • Click here to learn about the basics of HD mouse models

Epidemiological Studies^

Genetic Studies^

Fig Y-2: The Human Genome

Linkage Studies^

Human Postmortem Studies^

Family Tree Studies^

Clinical Studies^

For more information on clinical trials, click here.

For further reading^

    A technical paper regarding the transplantation of fetal neurons.
  3. Mouse paw picture obtained from National Geographic web site (

Updated by T. Wang, November 2010

Animal Research: The Ethics of Animal Experimentation

An Introduction to Animal Models of Huntington's Disease

Huntington’s disease research and drug testing frequently involve the use of mouse models. However, when different scientists refer to an HD mouse model they may not be referencing the same model. A variety of HD mouse models exist and are used regularly. This chapter will describe the most common HD mouse models, how they differ, and the ways in which they mimic the disease.

This article makes reference to both the mouse and the human huntington gene. The mouse huntington gene is a homolog of the human huntington gene, but there are subtle differences between them. For example, the mouse huntington gene has fewer CAG repeats than the normal human huntington gene, explaining why spontaneous mouse models of the disease do not exist. Despite this difference, the mouse huntington gene is 81% similar to the human huntington gene at the DNA level, showing that the two are true homologs. Different mouse models have been generated since the isolation of the HD gene in 1993. There are three general types of mouse model: knockout, transgenic, and knock-in.

Knockout models were the first models to be generated. These are models where the gene coding for the huntingtin protein (the mouse huntington gene) is removed or interrupted so that the DNA can not be transcribed. Although these models provide valuable scientific insights, they do not actually represent the disease because mice that are nullizygous for the huntington gene die during embryogenesis.

Transgenic models are made when the mutant human huntington gene, or a fragment of that gene, is inserted into the nuclei of a model organism. In transgenic models the gene insertion is not targeted to a specific location in the animal genome, meaning that where the gene inserts itself cannot be predicted. For a mouse model, this means that the mouse will express both the two normal copies of the mouse huntington gene as well as the human mutant gene or fragment that was inserted into its genome. It also means that the expression of the inserted mutant human huntington gene will not be controlled by the homologous promoter region of the mouse huntington gene. This frequently leads to much higher protein expression than normal endogenous levels.

Knock-in mice have either part of or the entire human mutant huntington gene inserted in place of part of or the entire endogenous mouse gene. Knock-in mice, therefore, carry the expanded CAG repeat mutation in the same place in the genome that it would appear if it were to develop naturally. This is the most faithful model in the sense that the mutant gene is located in the appropriate genomic context and will have the normal promoter region associated with the huntingtin protein. Knock-in mouse models can be either homozygous or heterozygous for the huntingtin mutation.

To learn more about the process of creating genetically modified model animals click here.

The remainder of this chapter considers the following topics:

More about knock-out mice^

Although knock-out mouse models are not a viable model of HD, studying these early models did increase understanding of the disease. Showing that a complete absence of the huntington gene, and consequently the huntingtin protein, was embryonic lethal revealed that Huntington’s disease is not a loss-of-function disease. The huntingtin protein is necessary for successful embryogenesis and when it is entirely absent the organism will die before birth. This suggests that the mutant huntingtin protein in individuals with HD must fulfill some of the same functions as the normal huntingtin protein.

Since most individuals with HD are heterozygous for the disease, they do still have one copy of the normal huntington gene and can express some levels of the normal huntingtin protein. However, HD homozygotes do develop normally and have an age of disease onset comparable to HD heterozygotes, confirming that the mutant protein fulfills some of the normal huntingtin protein functions. This suggests that HD is a dominant “gain of function” disease as HD patients are able to live with either one or two mutant HD alleles.

Some scientists suggest that despite the finding that HD is a gain-of-function disease, it is still possible that some loss of normal huntingtin protein function contributes to the disease. One study supporting this idea found postnatal brain degeneration in mice in which huntingtin was selectively inactivated in the brain and testes after early embryogenesis. Furthermore, another study found that normal huntingtin, but not mutant huntingtin, increases the production of brain-derived neurotrophic factor, which is necessary for the survival of striatal neurons in the brain. Although both of these studies support the conclusion that loss of normal huntingtin function contributes to the pathogenesis of HD, most researchers believe that HD should be considered a gain-of-function disease.

More about transgenic mice^

The earliest HD transgenic mouse models and still some of the most frequently used are from the line designated R6. In this model, a fragment encoding exon 1 of the human mutant huntingtin gene is inserted into the mouse genome. Four different R6 lines were established, with CAG repeat lengths ranging from 115-156. The R6/2 mouse, one of this line, is probably still the most commonly used HD mouse model. All four lines use the IT15 promoter. In humans it only takes a CAG repeat length of 36 or more to develop HD, but mouse models seem to need much larger repeat lengths to develop an HD-like phenotype, possibly due to their shorter lifespan.

Three of the R6 lines ubiquitously expressed the mutant huntingtin protein and exhibited an abnormal phenotype. The level of mutant huntingtin protein expression varied among these three R6 lines. The level of protein expression is usually represented as a percentage of the normal endogenous mouse huntingtin protein level. The R6/1 line had the lowest expression, measured at about 31% of endogenous mouse huntingtin levels. The R6/2 and R6/5 lines had an average expression of 75% and 77% endogenous mouse huntingtin levels. These lines displayed motor abnormalities such as chorea-like movements, weight loss, seizures, frequent urination, unusual vocalizations, and sudden deaths of unknown cause.

Newer transgenic mouse models now express longer fragments or the full length human huntington gene. One example is the YAC line. Mice from this line express the full length human huntington gene with a CAG repeat length of up to 128. These newer transgenic mouse models tend to show progressive motor abnormalities as well as neuronal loss in the striatum. These symptoms all closely parallel human symptoms in HD, and provide evidence that these mice might accurately model many aspects of the disease.

More about knock-in mice^

The first HD knock-in models did not display overt motor deficits like those observed in the first transgenic mouse models. Instead, they displayed some behavioral abnormalities such as increased aggression. The earliest models usually had between 70-80 CAG repeats. One reason that the early models did not reveal a phenotype resembling HD may be that they had a low number of CAG repeats for mouse models, which tend to have very high CAG repeat lengths.

Later knock-in models were more promising as they did show abnormal motor abnormalities, as well as cellular, molecular and neuropathological abnormalities suggestive of an HD phenotype. They also tended to reveal behavior abnormalities at earlier ages. These later knock-in models tended to have many more CAG repeats than the earlier models (from 94-140 CAG repeats).

Knock-in models are not all the same. Besides differences in CAG repeat length, there are also differences in how much of the mutant huntington gene is inserted and in the background strain of the mouse. In some models, only the sequence coding for the polyglutamine tract in exon 1 was replaced, while in others the entire first exon was replaced. The models that replace all of exon 1 with the mutant version should be more accurate representations of the human condition, because many of the proteins that interact with mutant huntingtin do so in the region immediately surrounding the polyglutamine tract. In other words, when a larger portion of the gene is inserted and it is expressed at an endogenous level, the mouse imitates the genomic context of the huntingtin mutation as well as the mutation itself, and consequently then phenotype may be more consistent with human HD. Most significantly, this means that any results found with these mice, either about relevant proteins, molecular pathways involved, or pre-clinical drug studies, are much more likely to be relevant to human HD.

Why do transgenic mice frequently display a more obvious disease phenotype?^

Transgenic mouse models sometimes seem to display a phenotype more similar to human HD than the phenotypes displayed by knock-in models. This might seem confusing since the knock-in models are theoretically more accurate representations of the disease genotype.

One reason for this unexpected result is that transgenic mice usually only express a fragment of the human mutant huntington gene. The mutation is then expressed as a truncated, or shortened, protein fragment. In vitro studies have founded the truncated protein to be more toxic than the full length protein, which could explain the more severe disease phenotype of these models.

In some transgenic models, this result could also occur because of unnaturally high expression levels of mutant huntingtin protein. Recall from above, for example, that HD line mice sometimes express as much as five times more mutant huntingtin protein than endogenous huntingtin protein. This overexpression could exaggerate the disease phenotype.

How are animal models used?^

Mouse models allow researchers to study aspects of the disease that would be impossible to do with human subjects. For instance, researchers can focus on changes in the brain or in cell-to-cell interactions during early stages of the disease with animal brain tissue. Mouse models are also a crucial part of early testing of potential therapeutics. Because mice have a shorter lifespan than humans, testing can be carried out much faster. Additionally, in the earliest stages of drug development it would be unethical to subject humans to the risks associated with the new drugs being tested.

Unfortunately, the use of mouse models in drug development does have some drawbacks. Mouse models of HD are not exactly the same as the human disease and there are also differences in how a drug will affect one species compared to another. Hopefully, as scientists develop more sophisticated models that better represent the genetics of human HD, model organisms will become more relevant for drug development and therapeutic testing. But it is always vitally important to keep in mind that drugs that look promising in animal models may not prove successful when applied to humans.

Further Reading^

– Adam Hepworth, 11-21-08

The HD Measuring Stick: Assessment Standards for Huntington's Disease

There are a number of well–established methods used to measure the severity and progression of Huntington’s disease (HD). These can evaluate a patient’s mental and physical capabilities and track any changes over time. Having standardized methods for measurement is important because it allows for the comparison of patients in clinical trials and the quantification of symptoms to guide treatment and therapy options.

Test Definitions^

Each of the tests measures the subject’s abilities to perform various mental and physical functions in different ways. The tests are often used together, providing a more complete picture of the patient’s physical and cognitive well–being.

It is important to recognize that the pages in this article are intended only to give general information about some of the different tests used clinically and in research. We do not recommend the self–administration of these tests. Accurate administration of these tests requires qualified personnel such as doctors, therapists, and other trained professionals.

Fahn Rating Scale (Physical and Mental)^

The Shoulson–Fahn functional capacity rating scale was first proposed in 1979. It measures independence in daily activities such as dressing, eating, managing personal finances, and engagement in occupation. Functional capacity in each category is ranked from Stage 1 to Stage 5, with Stage 1 representing the most independent level of function. The table below summarizes the scale as it was originally proposed:

Shoulson-Fahn Functional Capacity Rating Scale as Proposed in 1979
Engagement in occupation Capacity to handle financial affairs Capacity to manage domestic responsibilities Capacity to perform activities of daily living Care can be provided at
Stage 1 Usual level Full Full Full Home
Stage 2 Lower level Requires slight assistance Full Full Home
Stage 3 Marginal Requires major assistance Impaired Mildly impaired Home
Stage 4 Unable Unable Unable Moderately impaired Home or extended care facility
Stage 5 Unable Unable Unable Severely impaired Total care facility only

This table was adapted from Shoulson and Fahn, 1979. See further reading.

Unified Huntington’s Disease Rating Scale (UHDRS) (Physical and Mental)^

The UHDRS is a standardized rating system used to quantify the severity of HD. Used clinically and in research, it measures the patient’s abilities in four general areas: motor, cognitive, behavioral, and functional. The different portions of the test may be administered separately.

The following table summarizes the individual categories tested in the motor section of the UHDRS:

Skill Category Description
Ocular Pursuit the ability of the patient to follow a finger with the eyes in both the horizontal and vertical directions
Saccade Initiation the ability of the patient to turn the head in both the horizontal and vertical directions
Saccade Velocity the speed at which the patient is able to turn the head both horizontally and vertically
Dysarthria the presence of speech that is slurred, slow, and difficult to understand
Tongue Protrusion the ability to stick out the tongue and the speed to which the task is completed
Finger Taps the ability to tap the fingers of both hands (15 repetitions in 5 seconds is considered normal)
Pronation/Supination the ability to rotate the forearm and hand such that the palm is down (pronation) and to rotate the forearm and hand such that the palm is up (supination) on both sides of the body
Fist-Hand-Palm Sequence the ability to complete the sequence (making a fist, opening the hand palm down, and then rotating the hand palm up) more than 4 times in 10 seconds without cues is considered normal
Rigidity in arms the severity to which the range of motion of the arms is limited
Bradykinesia slowness in initiation and continuation of movements
Maximal Dystonia abnormal muscle tone (measured separately in the extremities, face, and trunk)
Maximal Chorea involuntary jerky movements of the body (measured separately in the extremities, face, and trunk)
Gait walking with normal posture
Tandem Walking the ability to walk in a straight line from heel to toe. The ability to do so regularly for 10 steps is considered normal
Retropulsion the ability to stand after being pushed back

In each category, patients are scored from 0 to 4, with 0 representing normal function, and 4 being the most severe dysfunction. The total score is the sum of the scores in the individual sub–categories. A higher UHDRS score indicates a more severe disease progression.

Zung Depression Scale (Mental)^

Patients with Huntington’s disease are significantly more likely to display signs of depression than people in the general population. Up to half of patients with HD demonstrate symptoms of depression. To learn more about the relationship between HD and depression, click here.

The Zung Depression Scale is a simple 20 item questionnaire. Patients judge statements about how they have been feeling on a qualitative scale ranging from “a little of the time” to “most of the time”. Each of the patient’s answers is then given a score from 1–4 and the sum of these scores is the total score. The range for total scores is between 20 and 80; patients with depression usually score between 50 and 69, while those with severe depression score above 70.

The scores and what they imply are summarized in the table below:

Score Indication
20-49 Normal
50-69 Depression
70+ Severe Depression

Mini–Mental State Examination (Mental)^

The Mini Mental State Examination (MMSE) assesses the overall cognitive status of patients. Its use is not limited to measurement of the progression of HD symptoms. For example, MMSE can also be used in the assessment of patients with other neurological diseases, such as Alzheimer’s disease.

It analyzes the patient’s abilities in 5 different areas of mental status: orientation, attention and calculation, recall, and language. Created in 1975, it is an effective 11–question test that only takes 5–10 minutes to administer and score. It has been used widely in both clinical practice and in research to measure the cognitive abilities of patients and subjects.

To test the patient’s orientation, he or she is asked what year, season, date, day, and month it is. He or she is then asked what state, country, town, hospital, and floor he or she is currently on.

Testing registration next, 3 objects are named, and the patient is given a chance to name all 3 of them. Assessing calculation abilities, patients are asked to count by 7’s.

Recall is tested by asking the patients to repeat the 3 objects he or she learned before.

Finally, language skills are tested in multiple parts. The patient is asked to name a pencil and watch, then is asked to repeat the phrase “No ifs, ands, or buts”. Next, he or she is asked to follow a verbal 3–stage command, and then a written command. Lastly, the patient is asked to write a sentence and copy the following drawing of two interlocking pentagons:

The successes and shortcomings of the patient are added up, and a total score is calculated. The maximum score on the MMSE is 30. Scores of 23 or lower are indicative of cognitive impairment.

Barthel Index (Physical and Mental)^

The Barthel Index (BI) is a commonly used scale to help assess the patient’s independence and his or her need for supervision or assistance. The test scores the patient’s ability to perform 10 basic daily living activities. Full credit for each criterion is not given if the subject needs even minimal help or supervision. The activities considered on this index include:

Scores for each individual item are given in increments of 5. The score for the items ranges from 5 to 15. The maximum total score is 100, and the higher the score, the more independent the patient.

Tinetti Scale (Physical)^

The Tinetti scale, also known as the Tinetti performance Oriented Mobility Assessment (POMA), is an easily administered test that measure’s a patient’s gait and balance abilities. The test takes approximately 10–15 minutes to complete and score.

The test is divided into two main parts, a balance portion and a gait portion. The patient’s balance in both the sitting and standing positions are measured. Additionally, the ability to stand from the sitting position and to sit down from standing up are quantified.

In the gait portion of the test, the subject is asked to walk across the room at a “normal” pace, and then back at a “rapid, but safe” pace. Various parts of the subject’s walk are noted, such as hesitation after being prompted to go, swing of the feet (height and path), step symmetry, step continuity, trunk sway, heel position, and smoothness of gait.

The test is scored on a 28 point scale. The indications for each score range are summarized in the table below. Scores ranging from 25–28 indicate a low fall risk, scores between 19 and 24 indicate a medium fall risk, and scores below 19 indicate a high risk for falls.

Score Indication
0-18 High risk for falls
19-24 Medium risk for falls
25-28 Low risk for falls

Physical Performance Test (Physical)^

The Physical Performance Test quantifies the subject’s performance in physical tasks. It is a standardized 9–item test that measures the subject’s performance on functional tasks:

Subjects are given two chances to complete each of the 9 items, and assistive devices are permitted for the tasks that require a standing position (items 6–9). Both the speed and accuracy at which the subjects complete the items are taken into account during scoring. The maximum score of the test is 36, with higher scores indicating better performance.

Symbol Digit Modalities Test (SDMT) (Mental)^

The Symbol Digit Modalities Test (SDMT) is a brief and simple mental test that takes less than 5 minutes to completely administer and score. The test measures the subject’s information processing speed and attention.

It involves a simple test in which numbers are randomly substituted for letters or geometric symbols. The subject is given a translation key, and is asked to translate them within 90 seconds. The task is easy for normal subjects to complete, but is more difficult for those patients with cognitive dysfunction.

The translation can be given in either a written or oral format. This flexibility in format allows for the testing of almost all subjects, including patients with speech or motor disorders. Additionally, the written format allows for the test to be administered to patients in a group setting.

Thurstone Word Fluency Test (Mental)^

The Thurstone Word Fluency Test (TWFT) is a simple test that measures the subject’s communication abilities. Given in either a written or oral form, the TWFT is commonly used to detect the presence of and define the nature of any cerebral dysfunctions.

First, the subject is given five minutes to write down or say as many words as possible that begin with the letter “s”. Next, he or she is given four minutes to list as many four–letter words as possible that begin with the letter “c”.

Several studies have shown that the TWFT is very accurate in identifying subjects with reduced cerebral function. However, the test is unable to identify which specific areas of the brain have been damaged. For example, the test can determine whether or not a patient has brain damage, but it cannot be used to detect whether the damage is on the left or the right side of the brain.

Despite its shortcomings, the TWFT is informative and is commonly used in combination with other tests to help gauge the presence and extent of brain damage in patients.

Stroop Test (Mental)^

The Stroop Test is a simple mental test commonly used to measure the subject’s attention and mental flexibility. It takes advantage of the Stroop effect, the interference that arises when the brain is presented with conflicting signals.

Patients are presented with a list of colors, like in the image below, each printed in a different color:

stroop test

Next, the subject is asked to name the color of each word rather than what the word is. For example, the correct response to the first word in the third column would be “red” not “blue”.

The subject’s accuracy and speed at the Stroop Test can be recorded and used to track the progression of cognitive disabilities.

Neuropathological Scales^

In addition to the tests discussed in this article, there are also various neuropathological grading systems which measure physical change in the brain as a result of the disease. One such scale that has been developed is the five–tiered pathological grading system, which rates damage done from Grade 0 to Grade 4, with Grade 4 having the most severe damage.

For further reading^

-A. Pipathsouk, 1-15-10

The Huntington's Disease Pipeline

Basic Research:

Target Identification and Validation:

Drug Optimization:

Drug Development/ Pre-Clinical Animal Studies:

Investigational New Drug (IND) Application:

Clinical Trials: Phase I

Clinical Trials: Phase II

Clinical Trials: Phase III

New Drug Application (NDA):

Clinical Trials: Phase IV:

Basic Research^

HD and Basic Research

Target Identification and Validation^

HD and Target Identification^

Drug Optimization^

HD and Drug Optimization^

Drug Development/ Pre-Clinical Animal Studies^

HD and Pre-Clinical Development^

Clinical Trials: Phase I^

HD and Phase I Clinical Trials^

Clinical Trials: Phase II^

HD and Phase II Clinical Trials^

Clinical Trials: Phase III^

HD and Phase III Clinical Trials^

Clinical Trials: Phase IV^

For Further Reading^

  • What is a Clinical Trial? Online
    A useful site from the Huntington’s Study Group that discusses the various phases of clinical trials in more detail.
  • Background Information for Clinical Research in Huntington’s Disease. Online
    A resource from HD Drug Works discussing the types of clinical trials that are conducted for HD
  • Clinical Trials currently being conducted for HD. Click here.
    A service of the U.S. National Institutes of Health

-J. Seidenfeld, 5/19/07


Reader Level:

Inter-process Communication Between Managed Process

By Mohamed Hasan on Jan 08, 2012
This article explains Memory Mapped Files for inter-process communication.

Inter-process communication between Managed Process

There are certain cases, where the developer needs to pass data to another process running on the same system. One of the efficient ways of handling the situation in a Win32 application is using memory mapped files. Mapping between a file and memory allows multiple applications to read and write in the file at the same time. Starting from .NET 4.0, Managed applications can use the memory mapped file functionality as the traditional Win32 application does.

Memory mapped files can be categorized into two types.

1.      Physical memory mapped file.

2.      Virtual memory mapped file.

Physical Memory Mapped File

Physical memory mapped files are also referred as Persisted memory mapped files. This category of memory mapped file is always associated with a physical file in your hard disk.  Very suitable for applications which need to work with huge data files. Once the last process is finished working with the physical memory mapped file, the contents of the file is written back to the source file on the hard disk.

Virtual Memory Mapped File

This category is also known as Non-Persisted memory mapped file. As the name means indicates, it is not associated with a source file on hard disk. It is very effective for run time data communication between two processes.

Let's have a closer look at programming the inter-process communication using the memory mapped files.

As any other files programing you do, the first step is to create the memory mapped file. System.IO.MemoryMappedFile class provides many different static functions to create the memory mapped file.

MemoryMappedFile.CreateNew static function takes 2 arguments. The first one is a string parameter specifying a unique name for the file. This name will uniquely identify the memory mapped file across the processes. The second parameter is a long data type, used to specify the maximum number of bytes that can be stored by the memory mapped file. While creating the file you can also specify the access mode for restricting the access to that file.

The following table lists the entire access mode supported.

Enumerator: MemoryMappedFileAccess

Member name

Read and write access to the file.

Read-only access to the file.

Write-only access to file.

Read and write access to the file, with the restriction that any write operations will not be seen by other processes.

Read access to the file that can store and run executable code.

Read and write access to the file that can can store and run executable code.

Once the file is created, the application must create a view of the file in order to read and write to the file. The view can point to the complete file or to a specific portion of the file.

MemoryMappedfile.CreateViewStream instance function creates a view stream which provides read write operations to the Memory mapped file. You can also create multiple views to the same part of the memory-mapped file, thereby creating concurrent memory. For two views to remain concurrent, they have to be created from the same memory-mapped file.

Once the stream is created, the applications can perform regular read and write operations on the file.

If another process wants to access the same file for read/write purposes, the second process should use "MemoryMappedFile.OpenExisting" function to open the file. OpenExisting function takes file name as an argument. This file name is a unique name, which was provided in the MemoryMappedFile.CreateNew function by the process one.

When two process trying to access the same file, of course it is the programmer's responsibility to make sure that we take care of the synchronization part of it. In the attached sample application, I have used a mutex to implement the synchronization between the processes.

Mohamed Hasan

Mohamed Hasan has 8 years working experience in   C++  and  .NET technologies. He holds Master's degree in Computer Science. Currently working on C#.NET, VC++, SQL Server 2008 and WPF.


FOOD ALLERGIES by ChrisCaflish

At least one third of all adults believe they have some sort of a food allergy, but true food
allergies affects less than 2% of the population. Only five percent of young children are
diagnosed with food allergies and many of those outgrow them by the time they reach

To a small percentage of the population, food allergies can be fatal. In 1993, three Rhode
Islander died as a result of allergic reactions to food; in two cases, the deaths resulted from
foods prepared in a commercial food establishment. The individuals did not know they were
eating foods to which they were allergic.

A food allergy is a violent reaction to an otherwise harmless food that involves the body's
immune system. An allergen is any substance which produces an allergic reaction. The ten
most common food allergens are:

Tree Nuts (i.e. Walnuts, Cashews)

Allergic reactions can begin within minutes to a few hours after eating the problem food.
However, in very sensitive individuals, just touching or smelling the food can result in an
allergic reaction.

Most often, but not always, the symptoms of an allergic reaction begin with: a sensation that
the lips and tongue are swelling; itching or tingling in the mouth; sensation of warmth;
redness to the skin, hives; tightness in the throat; eyes may itch, water and swell; nausea,
vomiting, cramping, diarrhea; Anaphylaxis occurs when several parts of the body have food-
allergic reactions at the same time. This condition is rare, but can be fatal.

Symptoms of food allergy vary among individuals as to the severity, when they begin and the
amount of food that is eaten. The same food can produce different reactions in different
people and different foods can cause the same reaction in one person. Individuals with
asthma appear to be at greater risk of food allergies.

Diagnosing and managing a food allergy requires medical treatment. Once the food allergy is
confirmed through an examination including a complete medical history and a series of
specialized tests, the only proven treatment is to avoid the offending food.
To eliminate the offending food from the diet it is necessary to read and understand food
ingredient labels. By law, a list of ingredients in each food product should be listed on the
label. Labels should be re-checked regularly as the ingredients in products change. Specific
information about the ingredients is available from the company producing or processing the
food product.

Foodservice establishments have a responsibility to provide correct and up to date
information about food items on the menu. "Secret" ingredients which are considered
allergens such as peanuts, nuts, eggs, milk, shellfish and fish should not be used in any food

Waitstaff should take customer inquires about allergies seriously. They should be familiar
with all the ingredients in the food items on the menu and how they are prepared. For
example, waitstaff should know the ingredients in a batter used to bread meats or fish. If the
ingredients change, they should be advised of the change.

Avoid cross contamination during preparation of food items. Cross contamination is the
transfer of one food ingredient to another food ingredient by a nonfood contact surface (i.e.
human hands, cooking utensils). An individual had an allergic reaction when he ate a
sandwich that had been made with a knife that had been used to make a peanut butter

If a patron has a allergic reaction, respond quickly. Ask if there is a history of food allergies
and check for a medical bracelet or necklace. In Rhode Island, the majority of individuals
with this problem carry a syringe loaded with epinephrine (Epi Pen) which can be easily
injected. Call 911 for immediate medical assistance. The sooner the reaction is treated, the
less severe it will be. People have died because they have disregarded their symptoms.

Persons sensitive to these specific allergens should avoid the following foods/ingredients:

            •   Eggs
                   o    Albumin
                   o    Egg (including whites and yolk)
                   o    Eggnog
                   o    Mayonnaise and other dressings
                   o    Ovalvumin
                   o    Ovomucoid
                   o    Simplesse
                   o    Egg-based glaze on baked goods

            •   Fish
                   o    Anchovy (including anchovy paste)
                   o    Caviar
                   o    Fish byproducts
                   o    Imitation crab (surimi)
       o    Roe
       o    Oil used to fry fish would case a reaction

•   Milk
        o   Cream
        o   Curds
        o   Dry milk solids
        o   Lactalbumin, lactalbumin phosphate
        o   Lactose
        o   Milk (derivative, protein, solids)
        o   Artificial butter flavor
        o   Butter, butter fat
        o   Buttermilk
        o   Casein, rennet casein
        o   Cheese
        o   Sour cream
        o   Sour cream or milk solids
        o   Caseinates (ammonium, calcium, magnesium, potassium, sodium)
        o   Whey (delactosed, demineralized, protein concentrate)
        o   Yogurt

•   Peanuts
       o Peanuts
       o Cold pressed peanut oil
       o Mixed nuts
       o Nu-nuts flavored nuts
       o Peanut butter
       o Peanut flour
       o Foods containing peanut protein including
       o Chinese and Thai dishes - egg rolls
       o Baked goods-pastries, cookies, danish
       o Candy
       o Chili
       o Marzipan
       o Soups

•   Tree-nuts
       o Almonds
       o Brazil nuts Cashews
       o Chestnuts
       o Filberts/hazelnuts
                  o   Hickory nuts
                  o   Giandiju (chocolate nut mix)
                  o   Macadamia nuts
                  o   Marzipan/Almond paste

Revised 5/00
University of Rhode Island
Cooperative Extension Food Safety Education

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Photography: Foundation Course

Color photography, RGB color model, Photograph

Photography is the art, science, and practice of creating durable images by recording light or other electromagnetic radiation, either chemically by means of a light-sensitive material such as photographic film, or electronically by means of an image sensor. Typically, a lens is used to focus the light reflected or emitted from objects into a real image on the light-sensitive surface inside a camera during a timed exposure. The result in an electronic image sensor is an electrical charge at each pixel, which is electronically processed and stored in a digital image file for subsequent display or processing. Photography has many uses for business, science, manufacturing, art, recreational purposes, and mass communication. It is invented in the first decades of the 19th century; photography seems to be able to capture more detail and information than traditional mediums, such as painting and sculpting. Photography as a usable process goes back to the 1820s with the development of chemical photography. The first permanent photo etching was an image produced in 1822 by the French inventor Nicéphore Niépce, but it was destroyed by a later attempt to duplicate it. Niépce was successful again in 1825. He made the first permanent photograph from nature with a camera obscura in 1826. All photography was originally monochrome, or black-and-white. Even after color film was readily available, black-and-white photography continued to dominate for decades, due to its lower cost and its classic photographic look. It is important to note that some monochromatic pictures are not always pure blacks and whites, but also contain other hues depending on the process. Color photography was explored beginning in the mid-19th century. Early experiments in color required extremely long exposures (hours or days for camera images) and could not fix the photograph to prevent the color from quickly fading when exposed to white light. The first permanent color photograph was taken in 1861...
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Brain Fog Anxiety Symptoms

Brain fog anxiety symptoms description:

Brain fog is often described as:

What causes brain fog?

Because there are many medical conditions that can cause brain fog, it’s best to discuss this symptom with your doctor. If your doctor attributes your brain fog to anxiety, you can feel assured that there isn’t a medical cause.

Anxiety activates the stress response. The stress response is designed to bring about certain physiological, psychological, and emotional changes that enhance the body’s ability to deal with danger – to either fight or flee.

These changes can affect how the brain functions. And if the stress response is activated too frequently or dramatically, the body can remain in a state of semi stress response readiness, which we call stress-response hyperstimulation. In other words, the body becomes overly stressed.

When the body becomes overly stressed, it can cause a wide range of sensations and symptoms. Experiencing a ‘foggy brain’ is a common consequence of persistently elevated stress, which being overly anxious can cause.

How to get rid of brain fog?

Ending an active stress response and/or reducing the body’s stress generally eliminates all sensations and symptoms of anxiety and stress, including brain fog. Because brain fog is a common symptom of anxiety and stress, it needn’t be a cause for concern.

Yes, brain fog can be uncomfortable and problematic as it pertains to thinking. But, it isn’t harmful. Again, brain fog is a common indication of an overly stressed body. Eliminating your body’s overly stressed state will eliminate this type of brain fog.

For a more detailed explanation about anxiety symptoms including brain fog, why symptoms can persist long after the stress response has ended, common barriers to recovery and symptom elimination, and more recovery strategies and tips, we have many chapters that address this information in the Recovery Support area of our website.

If you’d like personal assistance with your recovery, you can learn more about our Personal Coaching option here.

Return to's anxiety symptoms page or our anxiety symptoms mind page.

Authors: Jim Folk, Marilyn Folk, BScN. Last updated April 2015. Information, support, and coaching/counseling/therapy for problematic anxiety and its sensations and symptoms, including brain fog.


The Ionian Cities, the Threat to Greece, Marathon | The Greeks

The new Persian rulers would not allow their subjects political freedom, which was what the now-captive Ionian Greek cities most valued. Their prosperity declined, as the Persians drew away from Ionia the wealth from the trade routes that had formerly so enriched Aegean towns. By 513 B.C. the Persians had crossed the Bosporus, sailed up the Danube, and moved north across modern Romania into the Ukraine in a campaign against a nomadic people called Scythians.

The Growth of Bureaucracy

Bureaucracy is one of those words that has changed in connotation while also describing a major development that is part of “modernization.” As nation-states became ever more centralized and powerful, they tended to take on more and more responsibilities with respect to their citizens. Agencies of government, that is bureaus, were created to administer the various aspects of government: foreign affairs, excise and taxation, the police, social welfare, national education, and so forth.

The Enlightenment

Reason, Natural Law, Progress – these are the words by the eighteenth century.

It was the Age of Enlightenment, when it was widely assumed that human reason could cure past ills and help achieve utopian government, perpetual peace, and a perfect society. Reason would enable humanity to discover the natural laws regulating existence and thereby assure progress.

Germany and World Depression, 1929-1933 | Between The World Wars

But the economic depression had begun to knock the foundations out from under prosperity and moderation. An economic depression is a sharp and deep decline in trade and general prosperity.

In the worldwide depression of 1873 to 1896, prices had fallen, agricultural distress had intensified—made worse in Europe by bad harvests followed by wet summers and by competition from Argentine and Australian meat and Canadian and American grain—and banks had collapsed, especially in Austria and France.

I Have a Dream

In 1963, on the occasion of a massive civil rights rally held in the U.S. capital, Martin Luther King gave his most famous speech.

Calvinism and Predestination | The Protestant Reformation

For Calvinists the main theological concern was the problem of predestination against free will. The problem arose from the concept that God is all-powerful, all-good, all- knowing; this being so, he must determine all that happens, even willing that the sinner must sin. For if he did not so will, a person would be doing something God did not want, and God would not be all-powerful. There is a grave difficulty here. If God wills that the sinner sin, the sinner cannot be blamed for it. Logical argument appeared to be at a dead end.

Oliver Cromwell

Even today the character of Oliver Cromwell is the subject of much debate. Judgments on the English Civil War are shaped in some measure by opinions about Cromwell’s motives, actions, and policies. His supporters and detractors are no less firmly committed today than in Cromwell’s time, especially in Britain, where the role of the monarchy continues to be debated even now. Some commentators feel that Cromwell, as Lord Protector, simply replaced the king; others argue that he fundamentally transformed England, despite the eventual restoration of the monarchy.


Try the NEW!

Peanut Buddies

by WikiCamps

Developer Notes

Peanut buddies is an adrenalin fueled puzzle game where pairs of conjoined buddies fall from the top of the play field. The goal of the game is to destroy all the square blocks that are taking over the play field. Drag your buddies around to position them in a line of 4 or more of the same colour...


Green Investing Teams Up With Historic Preservation

p2110242The green movement in America is rapidly moving forward. Advice on investing in sustainable development comes at us from every angle, but one sector of the green market that isn't often discussed is historic preservation. It goes without saying that most historic architecture wasn't focused on sustainability or the environment, but that doesn't mean that going green plays no part in the future of historic preservation.

The question that some historic preservationists are asking now is this: why build new green structures of copper, glass and other reusable materials when we could simply reuse old buildings instead? The National Trust for Historic Preservation evidently asked themselves this question and answered it for us: "the greenest building is the one already built." And now, the Trust is reminding consumers that many historic structures are prime candidates for LEED certification.

The National Parks Service is also considering renovating many historic sights as cost-effective green buildings. Officials at Ft. Sumter in South Carolina, for instance, are evaluating the feasibility of solar panels and backup fuel cell generators. The officials say that would install the solar panels on the roof as to not disturb the historic feel of Ft. Sumter, proving that sustainability can be seamlessly integrated with classic architecture.

A major consideration for other government departments and independent contractors considering green-ing historic structures is the balance between the costs and benefits associated with new construction, the refurbishment to LEED standards of old structures, and the methods of traditional preservation and restoration. Nonetheless, historic preservationists are increasingly supporting the sustainable regeneration of original structures, an idea that makes buildings green but allows us to appreciate history.

Photo credit: Jeremy C Bradley


Synonyms and Antonyms of GAIN

the amount of money left when expenses are subtracted from the total amount received <the company posted a substantial fourth-quarter gain, signaling an end to their money-losing ventures>
usually gains pl  an increase usually measured in money that comes from labor, business, or property <net gains this year were better than last>

April 27, 2015
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Ailurophobia, and 9 other unusual fears


'Is it in the public interest?' is a question you need to ask before publishing personal information. The more private or intimate the information is, the greater the public interest justification needs to be.

This is a general and brief account of privacy law and some of the issues that may arise for journalists. It is not a comprehensive account of the law in this area, nor should it be relied upon to make any judgment. BBC journalists should always take specific advice from the BBC’s legal team.

Of course, what is in the public interest is not the same as what is of interest to the public.

In simple terms, the court will balance someone’s right to a private and family life against the media’s right to freedom of expression. This is an area of the law that has developed significantly following the incorporation of the European Convention on Human Rights into UK law in 1998.

Privacy law

Privacy law may be relevant, for example, when you are reporting stories about people’s personal or sexual lives, finances, information about their health, or filming them in their house without their permission. It can even sometimes include situations where the person is in a public place - for example, at a funeral.

Expectation of privacy

The first issue is whether the person had a reasonable expectation of privacy in relation to the information. One way of looking at this question is to ask yourself how you would feel if the information in the story you’re thinking of doing was published.

It does not include trivial information. Generally speaking, if the information is already in the public domain then it will not be private.

Public interest

If a court decides that a person has a reasonable expectation of privacy in relation to a piece of information or a situation, it then looks at the issue of whether, nonetheless, the public interest in the story outweighs this.

In broad terms, this is about whether the issue is of public importance rather than tittle tattle.

Examples of what might be in the public interest include revealing crime, protecting public health or exposing misleading claims by institutions.

The more private or intimate the information is, the greater the public interest justification will need to be for publication.

Invasion of privacy

The law allows people to bring actions for invasion of their privacy, for which the court can award damages. The level of damages is relatively low when compared to damages in libel. The highest recent award was £60,000. However, the legal costs of a case will usually be significantly higher than the damages awarded and are paid by the losing party.

Privacy injunctions are regarded by many as a more important way of protecting their privacy because once private information is published it is difficult to make it private again. As a result, people are usually more concerned with preventing publication of the story than with getting damages subsequently.

Privacy injunctions are orders of the court that prevent publication of the private information. These are often obtained on an urgent basis shortly before a planned story is due to be broadcast, when there is not sufficient time for the court to properly consider all of the arguments.

As a result, the court will often grant an ‘interim injunction’ which is put in place until a full trial of the issues.

Interim and super injunctions

If a person applies for an interim injunction, the court will decide whether or not the person seeking the injunction is more likely than not to succeed at trial - so in essence the court will look on a preliminary basis at the issues discussed above.

Sometimes, in order to avoid undermining the purpose of an injunction, the court will also order that the media is not allowed to report who has obtained an injunction (which is when you will see letters used instead of a person’s name in reports). In rare cases, it will order that the media cannot publish the fact that an injunction has been published at all (often called a ‘super injunction’).

Law & Standards

Photograph: Don Bishop/Getty Images


<![CDATA[Microscopes - Knowledgebase Articles]]> <![CDATA[How do I get replacement bulbs, extra eyepieces, and objectives for my microscope?]]> At this time, Celestron has few spare parts (bulbs, objectives, eyepieces, etc.) for microscopes.

The most common types of microscopes are classified according to the type of view they provide. A high-power or compound microscope gives a highly magnified view of a tiny cell, mineral grain, or pixel on]]>
<![CDATA[How does a microscope work?]]> A microscope works by producing an enlarged image of a small object.

Because the eye can only focus to about 10 in (25 cm), this limits its ability to see fine detail by simply moving in close]]>
<![CDATA[How does a microscope get light to the specimen? What do I need to know about illuminators?]]> The lowest-powered microscopes may not need any light other than that provided from room lighting or the sky. However, the microscope may be so close to the specimen that the instrument may shade it. Or y]]> <![CDATA[What is a condenser?]]> A condenser is a glass lens or lens system located within or below the stage (sub-stage) on compound microscopes. Its basic function is to gather the light coming in from the illuminator and to concentrat]]> <![CDATA[How do I calculate magnification for my microscope?]]> It’s very easy to figure out the magnification of your microscope. Simply multiply the magnification of the eyepiece by the magnification of the objective lens.

<![CDATA[What’s the resolution of a microscope? Is this related to numerical aperture?]]> A microscope’s resolution is its ability to form separate images of lines or dots. It’s defined in terms of the actual distance between details on the object. The wave nature of light puts a p]]> <![CDATA[What do the numbers on the barrel of the microscope objective mean? What about the letters DIN and JIS?]]> Microscope objective lenses will often have four numbers engraved on the barrel in a 2x2 array.

The upper left number is the ]]>
<![CDATA[How do I focus my microscope?]]> First, insert a slide or you specimen on the microscope stage. For first-time use, get an object with a clearly identifiable pattern, like the engraving marks]]> <![CDATA[What are parfocal objectives?]]> Parfocal refers to the ability to change objectives with differing powers and have the focus remain sharp. The distance from the top of the objective to the object being viewed is the parfocal distance.&n]]> <![CDATA[My microscope has a filter wheel. How is it used?]]> Filters are used to increase contrast and color correction for visual observations of specimens or slides. They may be used with live specimens as a non-lethal substitute for staining.

<![CDATA[My 100x objective is called a wet objective. What does this mean? What is oil immersion and why is it important?]]> A wet objective means it operates with oil between the lens and the specimen. Oil concentrates light from the condenser and reduces light losses from reflection and refraction. Oil immersion is the techni]]> <![CDATA[What is the difference among achromatic, semi-plan, and plan objectives?]]> Most microscope objectives come in three basic designs: achromatic, semi-plan, and plan.

An achromatic objective corrects for color and has a flat field across the central 65% of the image. It&]]>
<![CDATA[What is the working distance of my microscope?]]> There are two working distances for microscopes: objective and stage. Together they define the space you have to work with objects and still focus with your microscope.

<![CDATA[How do I use my microscope for photography?]]> There are several ways your microscope can take photos.

The first method is to use a ]]>
<![CDATA[What do I need to know about microscope stages?]]> Your microscope’s stage holds specimens and slides for examination.

Plain stages are usually fixed platforms with a cir]]>
<![CDATA[What’s the best microscope for looking at coins, stamps, jewelry, and rocks?]]> A stereo microscope is the best choice for looking at collectibles. Its lowest powers may allow you to see the entire stamp or coin. It has en]]> <![CDATA[What is the standard diameter of microscope eyepieces?]]> The international standard microscope eyepiece tube diameter is 23 mm or about 0.9 in. Many stereo microscopes use eyepieces with a barrel diameter of 30 mm (1.2 in).

<![CDATA[What would be the best microscope for surveying the contents of a petri dish?]]> A stereo microscope would be effective for examining petri dishes. The stage is large enough to hold big dishes, and the wide field of view will make it easy ]]> <![CDATA[What is bright-field illumination? How is it different from dark-field illumination?]]> In order to clearly see specimens, a microscope will need to light or illuminate them. The most common type of illumination for biological mic]]> <![CDATA[What is the resolution of my microscope in microns and image scale in microns per pixel?]]> A microscope’s resolution is its ability to form separate images of lines or dots. It’s defined in terms of the actual distance b]]> <![CDATA[What slides are included in the Prepared Slide Sets (#44410, #44411, and #44412)?]]> These sets have a wide variety of specimens for you to examine or demonstrate with microscopes.

#44410 is a 25]]>
<![CDATA[What do the abbreviations like wm, cs, and ls mean in descriptions of microscope slide specimens?]]> Types of permanent prepared microscope slides are described by standard abbreviations. Here is a list of the most commonly used abbreviations and their meanings:

<![CDATA[Does the Advanced Stereo Microscope (#44202) use standard eyepieces?]]> Yes, it uses standard diameter stereo microscope eyepieces of 30 mm barrel diameter.

Updated 12/18/13

<![CDATA[What are the three slide specimens in the Microscope Kit (#44121)?]]> There is no fixed list of slides included with this microscope as they are chosen at random, so each Microscope Kit (#44121) will have different slides.

The microscope needs 5-6VDC, 200-1000mA tip positive electrical input. The jack should be 5.5 mm OD, 2.1 mm ID, approx 12.5 mm long. If the jack won't insert due ]]> <![CDATA[Where are the slip covers that were supposed to come with my Celestron microscope?]]> Slip covers are small, thin sheets of glass that are placed over a specimen on a microscope slide.

You may think you are missing some of the ]]>
<![CDATA[What is the field of view on my Celestron optical microscope?]]> Celestron Optical Microscope Field of View Chart

The field of view  (FOV) is given for th]]> <![CDATA[Can I transfer images from the internal memory of my Deluxe Digital Microscope to an SD card loaded in the SD card slot on the unit?]]> No, you cannot transfer files to the SD card. Once the images are stored on the internal memory, they can only be transferred to a computer via the included USB cable.


During a windstorm a 34.0 m/s windblows over the roof of a building. The roof is 18.1 m long and 10.5m wide. It is constructed of materials with approximatelly22.4 kg per square meter. Assume thedensity of air of 1.21 kg/m3.
Calculate the net force acting on the roof due to the action ofgravity and wind, using, in the process, Bernoulli's equation as areasonable approximation. Use vertically upward as positivedirection.

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Gordon Ramsay Fights Over The Fat Cow

     MANHATTAN (CN) - Celebrity chef Gordon Ramsay countersued a former business partner who last month accused Ramsay of being a dictator.
     The "Hell's Kitchen" chef claims Rowen Seibel "tried to ride Mr. Ramsay's star, but through his own fraud, misconduct, and derelictions, brought the Fat Cow restaurant crashing down, while falsely blaming Mr. Ramsay and otherwise interfering with his rights."
     Ramsay claims in the lawsuit that Seibel concocted a "fraudulent scheme to freeload upon the renown and acumen of celebrity chef Gordon Ramsay."
     He claims that Seibel told him he needed Seibel to provide contracts for restaurants in Las Vegas in 2011. Then, after learning of Ramsay's plans to open The Fat Cow restaurant in Los Angeles, Seibel "begged to be included, this time promising Mr. Ramsey that Seibel would be an invaluable partner because of his significant restaurant experience," according to the lawsuit.
     "Having inveigled Mr. Ramsay to include him in The Fat Cow, Seibel took control of the restaurant and proved egregiously inept in its management," the lawsuit states, resulting in "food, service and business operations far below Mr. Ramsay's exacting standards."
     Ramsay claims Seibel "mis-paid" certain workers, which cost the restaurant thousands in penalties and back wages, and that Seibel hid the proceedings from Ramsay after a class action was filed seeking unpaid wages.
     Ramsay claims his efforts to save the restaurant were thwarted, because Seibel "refused to cooperate in any reasonable steps to solve the problems he had created."
     Ramsay says he then pushed to shut the money-losing restaurant, but Seibel insisted on continuing, "while at the same time refusing to provide funds needed to do so or to provide solutions to the trademark problems."
     "Seibel did and contributed nothing," Ramsay claims.
     "Seibel did not thank Mr. Ramsay for the effort," the lawsuit states. "Instead, Seibel filed a related lawsuit in this court, making the false and nonsensical claim that Mr. Ramsey, a successful television star and renowned restaurateur with a reputation for perfection, fraudulently induced Seibel to participate in The Fat Cow restaurant project with the intent to secretly cause to fail by producing a poor quality product and miring it in legal troubles so that he could then close the restaurant, make off with Seibel's money, and reopen a new restaurant in the same location. The claim is nonsense."
     Ramsay now seeks to dissolve the parties' joint ventures.
     He is represented Paul Montclare with Mitchell, Silberberg & Knupp.


A bill to be introduced in the state legislature next year would cut in half the time it takes lenders to sell abandoned properties.

Gov. Bill Ritter and state legislators announced the bill Tuesday at a news conference at the Clements Community Center in Lakewood. The bill, to be co-sponsored by Reps. Jeanne Labuda, D-Denver, and Dianne Primavera, D-Broomfield, and Sen. Mike John ston, D-Denver, will allow homes to be occupied more quickly so they don't become a safety hazard, a magnet for vandalism and other crimes, or a drain on nearby property values.

"Abandoned properties turn a family-friendly neighborhood into a hazard for children," Ritter said.

Current law calls for a minimum four-month sale process, but many foreclosure sales take seven to nine months to complete.

Currently, when a lender submits the paperwork to start the foreclosure process, the title for the property is still with the mortgage holder, even if the home is abandoned. That means there is no one responsible for maintaining the property, because the homeowner is gone and the home does not yet belong to the lender.

The bill would allow the bank to take over a property faster, giving municipalities and homeowners associations someone to hold accountable for maintenance.

"Before, we didn't discriminate between abandoned and non-abandoned," Ritter said. "When someone moves out and abandons their property, there's no reason not to move (the time frame) up and move it up quickly."

Colorado is on track to top the record of 39,900 foreclosure filings set in 2007 as widespread unemployment makes it harder for borrowers to make their mortgage payments. New foreclosure filings statewide during the third quarter reached a record high of 12,468, according to a report released last month by the Colorado Division of Housing. New filings for the first nine months of the year were up 18 percent to 35,112.

The number of completed foreclosures grew to 5,618 in the third quarter, the second consecutive quarter- over-quarter increase. But the total number of completed foreclosures fell to 14,971 during the first three quarters, compared with 16,265 during the same period last year.

The legislation would complement the $5.8 billion federal Neighborhood Stabilization Program designed to help foreclosure-blighted neighborhoods.

"More folks are fighting hard to maintain their mortgages," Johnston said. "The next critical step is to protect neighborhoods."

Margaret Jackson: 303-954-1473 or mjackson@denverpost.com


To conduct the test, PhotoSat constructed an elevation grid using automatic geophysical processing of 50-centimeter ground resolution stereo satellite images taken by DigitalGlobe's WorldView-2 satellite. The resulting elevations were then referenced against more than 20,000 gravity survey stations which had previously been established as being accurate to better than two centimeters.

For full article please visit: DigitalGlobe

Source: DigitalGlobe News Room

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Hit by Climate Change, Dwindling Antarctic Seal Population Grows More Diverse

Heterozygosity is not a trait that can be passed down directly to offspring, however, according to Staniland, so many pups are born with a high degree of genetic similarity and cannot survive the changing environment. Therefore, the overall population of the seals continues to decline, despite increased diversity. “They are not adapting to the changes in the environment,” he says.

Forcada stresses that heterozygosity in itself is not an evolutionary response, yet it could maintain higher levels of genetic variation, giving a greater chance of subsequent evolutionary adaptation that could help “buffer” the impacts of long-term climate change.

This new research is valuable because few studies have examined species’ response to environmental changes in such detail for such a long period of time, according to Staniland. “If we had just looked at the levels of heterozygosity in the population, then we would have seen an encouraging increase in overall fitness and the true picture of what was happening would have been missed,” he says. “Because we followed lots of different individuals over their life times, Dr. Forcada was able to show that actually the population was struggling and failing to adapt. With investment and developing technologies we hope to be able to see if the fur seal population response seen in this study is typical,” he notes, adding that he doesn’t know if the seals’ response to climate change is typical but that there would be reason to worry about any animal populations facing such environmental stress.

“Although some species have been known to evolve very quickly in response to the effects of climate change,” Forcada said in the video statement, “these seals are not adapting, they are not evolving. For them, the future is uncertain. Understanding these changes in the long term is one of the best things we can do to anticipate how the entire ecosystem is going to respond to future changes in the climate.”

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A voyage towards the North Pole : undertaken by His Majesty's command, 1773 / by Constantine John Phipps. Mulgrave, Constantine John Phipps, Baron, 1744-1792 Phipps, Constantine John, 1744-1792 text book London : Printed by W. Bowyer and J. Nichols for J. Nourse, 1774. 1774 English Tables. Journal of Phipps, the commander of the expedition of the ships Racehorse and Carcass towards the North Pole. The ships sailed north of Spitzbergen Island but were prevented by fields of ice from adv Arctic regions British exploration Northeast Passage Racehorse (Ship) Q115 Phipps http://www.biodiversitylibrary.org/bibliography/15240 0665285000 10294517 CaOOCIHM


Hikayat Aceh
text notes
list of words     search

Hikayat Aceh

Teuku Iskandar (ed.), De Hikajat Atjéh, ’s-Gravenhage: Nijhoff, 1958.  Verhandelingen van het Koninklijk Instituut voor Taal-, Land en Volkenkunde, deel 26.

Cod. Or. 1954, Leiden University Library.

text:  ±1600-1625;    manuscript:  ±1675-1700.

text:  Aceh;    manuscript:  unknown.

37933 words

to the pages (tp, 1-281) and lines of the underlying manuscript.

Editorial notes
This old text has many unusual features, which are thoroughly treated in Iskandar's notes.  Noteworthy are:
Spelling.  The Arabic script of the manuscript has many characteristic seventeenth century traits, but these are generally disguised by Iskandar's transcription, upon which the MCP text is based.  There are also a few instances of Acehnese influence on normal Malay spelling.
Vocabulary.  The text has many words which are found rarely or not at all in other Malay sources.  Iskandar provides an extensive glossary of rare words, and copious footnotes tracing items of vocabulary to Acehnese, Persian and Arabic origins.  Many of these are based on the annotations made earlier on the manuscript by an early Dutch scholar, perhaps Leidecker (before 1701).
Morphology.  Word formation is sometimes influenced by Acehnese in, for instance, different patterns of nasalisation, and particularly  (a) the use of mem- for memb- ;  and (b) the use of nasalisation alone in place of the meN- prefix.  Also noteworthy are the frequency of the -i verbal suffix, the occasional use of be- for ber-, and some non-standard or complex morphologies like berlihat  or sekelamaannya.

Iskandar's edition appears carefully prepared and well annotated. It is not a diplomatic edition; indeed this would have been undesirable given the difficulties the text presents.  Nevertheless, in a few places where Iskandar has emended the text, I have restored the original reading, always noting Iskandar's emendation as well.
Added:  1999 - April 2000
The text was scanned in Canberra by the MCP using Recognita™ OCR, and its spelling modernised.
The pages of the manuscript are indicated in Iskandar's edition; the lines have been imputed.


Michael Sarver

41 Shouts   -   37,044 Scrobbles

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    Ferris Wheel - (3:07)  -  41 plays
  2. Miss You Something Crazy - (3:45)  -  16 plays
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    You Are Not Alone - (3:58)  -  17 plays
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Obadiah 1:16-17 KJV

17 But upon mount Zion shall be deliverance,a and there shall be holiness; and the house of Jacob shall possess their possessions.

References for Obadiah 1:17

    • e 1:17 - deliverance: or, they that escape


Animal Fibre - Silk

What is cool in summer and warm in winter? The Chinese guarded the making of this fabric with their life What fabric are we talking about?
Yes! We are talking about silk, the queen of textiles. Silk is a type of an animal fibre produced by the silkworm.

Discovery of silk:  Chinese legend has it that empress Si-lung-Chi was worried about the damaged mulberry leaves in her garden. Emperor Huang-ti found out that the white worms were eating up the mulberry leaves and spinning shiny cocoons. A cocoon accidentally dropped into the empress’s cup of hot tea, and the delicate tangle of threads separated from the cocoon, thus leading to the discovery of silk.
Thus, the silk industry was born in China. This was kept secret for hundreds of years. later this was introduced in other countries by traders and travelers much later. The route they travelled was called the silk route.

Properties of Silk:  Silk is an elastic, lustrous protein fibre. The soft silk thread is as strong as a comparable steel thread.

Types of Silk:  Different types of silk moths yield different types of silk yarn, such as mulberry silk, tassar silk, eri silk and moonga silk.The most common silk moth is the mulberry silk moth. It’s Latin name is Bombyx mori.
Let us discuss about the life cycle of silk moth.

Life Cycle – Silk Moth:  Actually silkworms are not worms, but the larvae or caterpillars hatched from the eggs of the silk moth. The life history of a silk moth starts when a female silk moth lays eggs.

The larvae or caterpillars hatched from the eggs of the silk moth. These silkworms feed on fresh mulberry leaves the silkworm grows in size and then becomes a pupa.

In the pupa stage, it weaves a net to hold itself.  It then swings its head from side to side, secreting a fibre that hardens on contact with air. This fibre is made of a protein and becomes the silk fibre.

The caterpillar covers itself completely with silk fibre and turns into a pupa, this covering is known as the cocoon. The moth continues to develop within the cocoon. The silk thread or yarn is obtained from the silk moth’s cocoon.

Rearing Silkworms:

Sericulture:  Sericulture, or silk farming, is the rearing of silkworms for the production of raw silk. Silkworms are reared under suitable conditions of temperature and humidity to obtain silk threads from their cocoons. The female silk moth lays hundreds of eggs.
These are stored on strips of cloth or paper. Mulberry leaves are the staple diet of silkworms. When the mulberry tree bears a fresh crop of leaves, the eggs are warmed suitably so that the larvae hatch from them.
The larvae, caterpillars or silkworms are then stored in clean bamboo trays and are fed freshly chopped mulberry leaves. They eat day and night, and grow to enormous sizes.
The bamboo trays are provided with small racks or twigs to which the cocoons can be attached.
This happens usually after 25 to 30 days when the caterpillars stop feeding and move to the twigs to spin cocoons. The silk moth develops inside these cocoons.

Interesting fact about Caterpillar: As the caterpillars grow bigger, they shed their skin. The skin of the caterpillar does not grow along with it. So, it sheds its skin, and underneath the old one is a new skin. Caterpillars may shed skin four or five times!

Processing Silk:  Extracting silk from the cocoon is called processing silk.
The first step is to separate the silk fibre from the cocoon. For this, they need to be exposed to warmth.
Piles of cocoons are kept under the sun, boiled or exposed to steam. The warmth causes the silk fibre to separate from the rest of the cocoon.
The next step is called reeling the silk, which is the process of delicately unwinding the fibre from the cocoon.
Reeling is also done in special machines.
The silk thread is then bleached and dyed into many shades.
The silk fibre is then spun into silk thread, which is then woven into silk cloth by weavers.

Activities & Simulations

Activity1: has developed an about silkworm life cycle, silk cultivation and fashioned in silk with interseting images from the ancient times. The simulation is based on images. You can learn the concept through images which excelently desingned in understanding the concept.
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Activity2: has developed an interactive simulation regarding the life cycle of silkworm. The simulation is totally image based about each stage of silkworm.
Go to Activity

Activity3: has developed an interesting simulation regarding life cycle of silkworm through intersingf images and explanation for the each stage of silkworm life cycle. The simulation containes interesting question through the quiz.
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Questions & Answers

1 . Life cycle of silk moth
Life cycle of a silk moth: <...
2 . fibre to fabric
Ans: The hairs on the skin help to control body temperature. The hairs trap a layer of air above the skin, which helps to i...
3 . Activity

What is the activity ?

4 . what is cocoon
Ans:  When the caterpillar is ready to enter the next stage of its life history called pupa, it first weaves a net to hold...
5 . How is silk made?
Silk is made by silk worm