August 1991

Color Vision

Peter Lennie

The most useful question to ask initially about color vision is "What is it good for?" The best answer is probably that it allows us to distinguish and identify objects that otherwise would be confused. This emphasis on the properties of objects prompts us to ask whether the characteristics that determine their colors are stable, and how these characteristics might be economically represented in the brain. Most surfaces do have stable attributes, so one might cast the problem of color vision as one of representing the color attributes reliably, despite differences in the conditions under which the objects are viewed.

Retinal Regulation of Visual Contrast Sensitivity

Mechanisms for Motion Perception

One the goals of vision science is to understand the workings of visual systems from the diverse perspectives of psychophysics, neurophysiology, and computation, and to develop this understanding into an integrated theory of vision. This program has been particularly successful in the study of motion perception.

The Use of Neuroimaging in the Study of Vision

Visual neuroscience has been the focus of inquiry across many disciplines and has produced an explosion of understanding about how visual information is processed. A fundamental question is: Where are the computations necessary for vision performed?

Optical engineering challenges of the IBM 3800 laser printer: Part I

The IBM 3800 laser printer is a computer system printer that uses a He-Ne laser, acousto-optic modulator, and rotating polygonal mirror to produce raster scanned electrophotographic printing. It was the first commercially available laser printer and was originally designed for 144 x 180 PEL/inch resolution. It incorporated a forms flash system for forms overlay and merging with computer generated printing. Depending on the timing of the engineering activity, "engineering challenges " can be: (a) a feature of the basic design or (b) solutions to problems incorporated at some later stage in the research/development/manufacturing process. Part I deals with the optical design challenges encountered during development. Part II will discuss the manufacturing challenges.

EC '92 pushing ophthalmic standards

This month we focus on more global issues of standardization and consider some of these issues as they relate to ophthalmic optics. There are presently two international efforts being pursued in optics standardization—one a truly international effort sponsored by ISO and the other a European-based effort run by CEN that is motivated by the 1992 free market plan for Europe.

Otherwise the sky would be black ...

The other day, my daughter was in a chattery mood, and commented to me that it's sometimes hard having a "scientist" for a mom, because you can't always discuss things with her. "How's that?" I asked. "Well, one of the great mysteries of childhood is why is the sky blue? Every kid has their own theory. But I can't even discuss it with you, because you'll tell me why it's blue." I think she has a point. We all know kids love to be impressed with experiments, but often young kids really prefer not to hang around for an explanation. And I'd forgotten how much fun it is just to speculate. I remember in high school my friends enjoyed talking about dilemmas like what if a car is doing the speed of light and you turn on the lights. Sometimes speculating can be more interesting than finding out, when you're young.

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Basic Terms of Shinto

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A style of shrine architecture represented by the honden of the two Kamo shrines of Kyoto. The most widespread style today, it is thought to be a development of the Nara period under the influence of Continental culture.

A priestess belonging to the Board of Ceremonies in the Imperial Household Agency (Kunaichô). Naishôten attend exclusively to religious ceremonies in the shrines of the imperial palace.

Nakatomi no harae[Glossary: nakatomi_no_muraji]

see Harae

Naobi no kami[Glossary: naobi_no_kami]

Deities who restore conditions to normal. They remove all sin, pollution, and disaster to bring back the pure, bright, correct, and straightforward world of the gods. Ô-naobi-no-kami means "Great Naobi God." Kan-naobi-no-kami means "Sacred Naobi God."

Naorai[Glossary: naorai]

see Matsuri

Natsu matsuri[Glossary: natsu_matsuri][Glossary: kitano_tenjin]

Summer festival. Summer is the season when pestilences, insect damage to crops, and unexpected disasters such as storms and floods are most likely to occur; summer festivals characteristically are held to pray for protection against such calamities. Major summer festivals in Japan include those of Yasaka Jinja (Gion Matsuri), Kitano Jinja, and Iwashimizu Hachimangû.

Negi[Glossary: negi]

see Shinshoku

Nenchû gyoji[Glossary: nenchu_gyoji]

[Nenchu gyoji] The cycle of annual events traditionally observed by a family, a village, or on a national scale. Includes observances such as New Year's celebrations, the Doll Festival on March 3, Children's Day on May 5, tanabata, bon matsuri, moon-viewing on the 15th of the eighth lunar month, and shichi-go-san.

Ne no kuni[Glossary: ne_no_kuni]

Also called ne no kuni soko no kuni. The subterranean world. Often thought to be the same as Yomi.

see Nihon shoki

Nihon shoki[Glossary: nihon_shoki]

The Chronicles of Japan, a classical Japanese history written in Chinese. Compiled at the imperial court in 720 under the influence of continental culture, it indicates the development of a national consciousness. Thirty volumes of historical narratives cover the time from the age of the gods through the reign of Empress Jitô (r. 690-697). The first half of the work contains many myths and legends, while the latter half is more historically reliable. Together with the Kojiki, it is an important source for Shinto theology.

Niinamesai[Glossary: niinamesai]

see Aki matsuri

Ningen-shin[Glossary: nigimitama][Glossary: yasukuni_jinja]

Human kami. Of the numerous kami worshiped in Shinto, many are the spirits of human beings worshiped as kami. For example, the spirit of Sugawara Michizane is worshiped as Tenjin, the spirit of Tokugawa Ieyasu is worshiped as Tôshôgu, and the spirits of the war dead are worshiped as gods at Yasukuni Jinja. It should be noted that it is not the individual but rather that person's spirit (tama) that is revered and worshiped as a kami.

Dance of the ninjô, the conductor of the kagura orchestra. During the Heian period, the Konoe-toneri (head of the imperial guard) performed this function. As the master of ceremonies, the ninjô plays an important role in kagura, in the burning of the niwabi fire, tuning of instruments, and assembling of musicians. As he dances, the ninjô holds in his hand a branch of sacred evergreen to which is attached a ring called a wamuchi.

Norito[Glossary: norito]

Words addressed to a deity or deities in an ancient style of Japanese. The chief priest recites the norito (a general term including norito, yogoto, and iwaigoto) on behalf of the faithful. It was believed that beautiful, correct words brought about good, and that words of the opposite sort caused evil. This attitude stems from a belief in kotodama, a spiritual power residing in words. The style of expression is typified by the norito recorded in the Engi shiki, the book of court procedures compiled in the tenth century. Norito include words of praise for the gods, lists of offerings, words identifying the persons originating and pronouncing the prayer, and the subject of the prayer; but they contain no didactic elements. With the establishment of state Shinto (see Kokka Shintô) in the Meiji period, shrine norito were standardized by the government, but these restrictions were removed after World War II.

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How does OVT work to ensure that where U.S. citizens are injured or killed in terrorist attacks overseas, investigation and prosecution remain a high priority within the Department of Justice?

Who does OVT assist?

How can I stay informed about the investigation and prosecution of an overseas terrorist attack?

Will the perpetrator of the terrorist attack be prosecuted? If so, where?

If there is a court case, will victims be able to attend?

As a victim, do I need to hire a lawyer if the trial is in a foreign country?

OVT’s efforts to identify victims, monitor victim cases, and ensure victims’ rights help keep victim cases and issues a priority with investigators and prosecutors. Moreover, maintaining communication and cooperation with victims is a key element in a successful investigation and prosecution. Through its advocacy on behalf of victims and in serving as a bridge between victims and decision-makers, OVT has made many valuable contributions to the investigation and prosecution of terrorism offenses domestically as well as abroad and kept justice for the victims a primary Department goal. OVT’s efforts include the following:

  • OVT reports directly to the office of the Assistant Attorney General for National Security. Direct reporting enables OVT to raise U.S. citizen victims’ issues, views, and concerns at a high level in the Justice Department.
  • OVT’s Director participates in weekly meetings led by the Deputy Assistant Attorney General for Counterterrorism and Counterespionage to stay current on case status and ensure that U.S. victims are identified and their issues addressed.
  • OVT coordinates meetings between senior Justice Department officials and U.S. victims of overseas terrorism.
  • OVT staff sends daily case updates to staff in the Assistant Attorney General’s office and prosecutors and investigators around the country and abroad.
  • OVT has conducted extensive training on victims’ rights and services in overseas terrorism cases.
  • For the past four years, OVT has sponsored a commemoration ceremony within the National Security Division for National Crime Victims’ Rights Week.

Who does OVT assist?

OVT supports and assists U.S. citizen victims and families of U.S. citizen victims who are injured or killed in terrorist attacks in foreign countries.

Congress indicated that OVT’s purpose is “...to ensure that the investigation and prosecution of deaths of American Citizens overseas are a high priority within the Department of Justice…” Conference Report, H.R. 4818, Title I, Section 126 (108th Congress). When establishing the Office, the Attorney General stated that the geographic scope of the Office will not be limited to any specific region, but, instead, will extend more generally to terrorist attacks against Americans abroad, including such countries as Canada and Mexico. The Attorney General interpreted the legislation not to apply to attacks against American members of the armed forces or National Guard in war zones.

Where the direct victim is deceased, incapacitated, or a minor, services will be provided to representative victims, such as spouses, legal guardians, parents, children, siblings, other family members or other persons designated by a court. More than one representative victim can be identified depending on the circumstances. A person being held as a hostage will be considered an incapacitated direct victim. Accordingly, family members will be considered representative victims.

In keeping with Justice Department policy, OVT operates under a presumption in favor of providing rather than withholding services. See Attorney General Guidelines for Victim and Witness Assistance, Art. II.A (May 2012). OVT provides additional assistance to victims where appropriate and within available resources, as situations warrant. (Id.) (See also Id. at Article III.I).

how can I stay informed about the investigation and prosecution of an overseas terrorist attack?

OVT will work to keep victims and their families informed about significant developments related to an overseas investigation and prosecution of a terrorist attack. Please keep in mind, however, that OVT strives to convey only information which has been verified by a trustworthy source. Oftentimes media reports, especially as they relate to the criminal justice system of a foreign country, may be inaccurate or incomplete. OVT maintains password secured websites with information on many attacks against American citizens. If you are victim or the family member of a victim you can email OVT to request access and password information for the relevant attack at nsd.ovt@usdoj.gov. OVT also provides victim information through phone calls, emails, letters, and personal briefings.

For information about a U.S. government investigation or prosecution, OVT will put victims in touch with the appropriate FBI or Justice Department contacts. The FBI is the U.S. investigative agency. U.S. prosecutions are handled by the Counterterrorism Section in the Justice Department’s National Security Division and by a United States Attorney’s Office.

Will the perpetrators of the terrorist attack be prosecuted? If so, where?

Foreign Prosecutions: Terrorist attacks in foreign countries are usually a crime in the country where the attack occurs.  Many times the government of the country where an attack occurs will pursue justice in its own criminal justice system for all of the victims, including U.S. citizen victims.  Law enforcement agencies in the country where the attack occurs have sole jurisdiction to investigate crimes within their borders.  Foreign law enforcement’s ability to investigate crimes can vary greatly based on many factors, including capability, training, resources, and degree of control over the geographical location where the crime occurred.  If law enforcement is able to collect sufficient evidence to bring charges and apprehend the perpetrators, the crime may be prosecuted in court.    Some countries have special terrorism or military courts that handle terrorist crimes, while in other countries terrorist crimes are handled in the ordinary criminal courts.

Prosecution in the United States: The Department of Justice is committed to the principle that those who engage in or materially support terrorist acts against U.S. citizens must be brought to justice, whether in the United States or elsewhere, regardless of where the attack took place.  Accordingly, the Department remains committed to bringing appropriate charges against the perpetrators of such acts in the United States whenever such prosecution would be feasible and supported by evidence in our possession.

Generally, the following steps are necessary for a prosecution in the United States:

(1) Evidence Collection: Sufficient admissible evidence must be obtained, including from foreign authorities.

(2) Charges: A Grand Jury must charge the perpetrators in an Indictment or the Prosecutor must charge the perpetrators through an Information or Complaint.

(3) Arrest: The persons charged must be arrested either in the United States or overseas.

(4) Extradition (or other lawful removal and return of the suspect): If a charged person is in the custody of a foreign government, the foreign government must agree to transfer the person to the United States to stand trial.

This process can take many years. Sometimes charges are filed in the United States, but are not made public. One purpose for nonpublic charges is to make it easier to capture the perpetrators. Although the FBI and prosecutors are generally legally required to provide victims with information about the status of a United States investigation, government staff will not always be able to share particular details about the case because it could interfere with the investigation, would violate a court order, or would otherwise be inappropriate.

The United States may not be able to prosecute a case that occurs in a foreign country, even when a foreign nation cooperates with the FBI. Some of the reasons may include:

  • The evidence collected in a foreign country may not be admissible in U.S. courts.

  • The United States does not possess sufficient admissible evidence to prove guilt of a perpetrator beyond a reasonable doubt.

  • A foreign country’s prosecution may take precedence.

  • The host country may decide to imprison the perpetrator.

  • The host country may not agree to extradite the perpetrator to the United States or there may be legal or other obstacles to extradition.

  • The perpetrator cannot be found or apprehended.

  • There may be concerns about compromising the investigation if an arrest is made while the case is still being investigated.

If there is a court case will victims be able to attend?

Depending on the location of the court proceeding, victims may be able to attend. It is also possible that security concerns, the laws of that country, or some other factor may affect victims' ability to observe court proceedings. OVT will work to inform victims about the status of court proceedings, providing as much information as is allowed. OVT will also advocate for victim participation within foreign court systems.

In the United States federal courts, victims have a right not to be excluded from public court proceedings.

as a victim, Do I Need to Hire a Lawyer if the Trial is in a Foreign Country?

The decision to hire a lawyer to represent your interests as a victim is a very personal decision based on a number of important factors. While some countries may, as a matter of law or legal tradition, provide victims or their surviving family members with legal representation, the vast majority of countries do not. A comprehensive discussion of the factors to consider before hiring a foreign attorney may be found on the Department of State’s website .

Updated July 26, 2016


Your hidden potential as a Shadow God

But I promised things would get more interesting, didn’t I? Well, it would ruin the story to tell you everything right now, but you are destined to become a Shadow God, a spiritual warrior that protects the mortal world from monsters – shadows, ghost, ghouls, vampires, and worse – that come from a place known as the Shadow Realm.

A Shadow God is an alternate form that you take, that allows you to fight and kill those monsters. Because of this, you will be essentially creating two characters ~ one, your middle-school aged Human self, will change very little throughout the campaign. The other, your spirit-powered Shadow God self, will grow by leaps and bounds as the anime progresses, giving you more and more power and allowing you to defeat stronger and stronger foes.

Your Shadow God form is the same as your Human form, as far as the appearance of your body goes. Your clothes will be different ~ your alternate you assuming more traditionally Japanese garb (be it a kimono + sword, or samurai armor, or ninja clothing, etc). You’ll want to come up with your fantastical appearance. A picture from anime that closely resembles your idea, or a picture you draw yourself, will help everyone visualize the change and the concept in your mind.

Another vital aspect of your Shadow God form is your weapon. Your Shadow Slayer is the special weapon of a Shadow God, and it s very strongly tied to your character’s spirit and their eventual progression. You should choose a traditional weapon type for your Shadow Slayer. Most people will use a Sword or Katana, or similarly bladed weapon, but others will do bows or nunchaku or bo-staves, etc. Modern weapons, such as a gun, can’t be used for your Shadow Slayer (although you can ask me if you have a really good reason you want an exception). Don’t be afraid to make your weapon a bit unique ~ double-weapons are ok, so are ninja-weapons such as daggers, sai, and shuriken. Polearms are fine, and Asia has a large variety of them to draw inspiration from. You can also use medieval European weapons if you want, such as a western style bastard-sword / claymore, a glaive or poleaxe, etc etc etc. Two-sword style fighting is rare among Shadow Gods, but don’t be afraid to go all Musashi on the bad guy’s butt if you want.

Your Shadow Slayer is a sentient being, and has a form that can be manifested at a later point in the campaign. You’ll want to create a description of the “spirit” of your Shadow Slayer, its looks and basic personality, but the spirits will be NPCs under the GM’s control rather than role-played by yourself. Many Shadow Slayer spirits are human in form, but there are known to be some animals, monkeys, snakes, and even magical beasts such as dragons or chimera. The important part is to make the Shadow Slayer not only a part of your personality, but to have it be a complimentary personality to your character’s personality. It is a part of you, while at the same time it is its own unique individual being as well. It can be fun to make the Shadow Slayer’s spirit get along with you in perfect harmony, and it can be just as fun to introduce a personality conflict between the two that forces a different kind of character growth.

Shadow Gods often use magic, in addition to their Shadow Slayer. The magic has no name, and is more ancient than the Shadow Gods themselves, but it has been split into five elements ~ Fire, Water, Earth, Air, and Shadow.　火　水　土　風　蔭　 The elements all operate differently, with Fire and Air magic being more offensive, while Earth and Water magic are both more defensive. Shadow magic is both offensive and defensive. Only Water and Air have restorative properties. Shadow can have control over time itself, at higher levels.

All Shadow Gods have a level of affinity to the Shadow element. That is the magic that allows them to dissolve their mortal form and enter into the Shadow God form. Shadow is the magic that has control over Death and the Shadow Realm ~ essentially switching forms is like dying and then being reborn. However, it is uncommon beyond the base affinity for a Shadow God to really master Shadow Magic, because it is the most difficult of the elements to control. The most common element is Fire, because of its strong offensive power, and the next most common element is Water, because of its restorative properties. Earth and Air are less common, again because they are more difficult to use than Water and Fire.

Elemental magic is not even the only type of magic that is available to your characters, if desired. Other types of magic in the world would include Rune Magic, Shamanistic magic, Shinto magic, Scrolls, and so forth. Naruto-style “Ninjutsu” is also ok, and it can be fun to have “inherited” powers from your ancestors (the Sharingan Eye, for example). Anything beyond the five elements, however, will require cooperation with the GM to design for your character.

And don’t forget good ol’ hand-to-hand combat. Especially with a lighter, more “ninja” like weapon, or even a Shadow Slayer that is a fist-weapon like claws, you can certainly “Rock Lee” your way about combat, relying not on magic but on your highly-trained and powerful body to do the damage you need done. There is plenty of room for muscle, speed, and everything in between, and any martial arts style you know of or can make up.

All in all, the Shadow God form is a way to bring out a lot of the personality and inner strength of your character, and is probably among the most important, if not THE most important thing you will be creating as a part of your character. This game will be very combat-heavy, so it is advised that you do your best to create the strongest Shadow God character that you can.

The Character Creation section will contain more information about how to create a Shadow God, as well as providing a number of example characters to learn from.

Your hidden potential as a Shadow God

December sushigaski


Bulls Cast: Episode 22

In this episode of the Bulls Cast, Mac, Etheria and Lamar sit down to talk NBA free agency. Why did the Bulls sign Vladimir Radmanovic? Where does Dwight Howard want to be traded this week? Later in the show, the guys debate whether or not the 1996 dream team could hang with the 92 team.

Follow on Twitter @Midwaymadness


FORMER Winchester Canon Residentiary The Very Revd Alexander Wedderspoon has died aged 83.

During his time at Winchester, Wedderspoon - the son of a Church of Scotland minister - proved himself an adept and foresighted Treasurer.

He was the driving force behind the opening of the pastoral and educational centres in The Close, and eventually became the chairman of the national Cathedrals’ Finance Conference.

Wedderspoon retired in 2001, and lived in Cranleigh until his death on June 10.

His funeral was held at Guildford Cathedral last week.

He is survived by his wife, Judith, daughter Caroline, and son Michael.


The figure shows the essential parts of a hydraulic brakesystem. The area of the piston in the master cylinder is 6.41cm2 and that of the piston in the brake cylinder is 1.75cm2. The coefficient of friction between shoe andwheel drum is 0.541. If the wheel has a radius of 34.4 cm,determine the frictional torque about the axle when a force of 43.9N is exerted on the brake pedal.

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Drug-resistant bacteria loom as a growing health threat

In the first half of the 20th century, many of the leading causes of death, such as pneumonia, diarrhea, tuberculosis and enteritis, were linked to bacteria.

The discovery of penicillin and subsequent generations of antibiotics dramatically altered these numbers. For decades, humans have won battle after battle against bacterial infection. The war, however, is not going so well.

Increasing antibacterial resistance has rendered many antibiotics ineffective or obsolete. Microbes are evolving faster than the development of new drugs. The Food and Drug Administration is considering offering financial incentives to the pharmaceutical industry, like tax breaks and patent extensions, to encourage greater, speedier drug discovery.

Dr. Victor Nizet is a veteran of the antibiotic wars. A UCSD professor of pediatrics and pharmacy, Nizet’s lab investigates how bacterial pathogens interact with humans, and how best to kill, disarm or deactivate them. We asked for a report from the front lines.

Q: Some scientists say we’re losing the war against drug-resistant bacteria, that ordinary infections may again become a major cause of death. Just how bad is the situation?

A: Drug resistance in bacteria is a very serious public health problem. When the first-choice antibiotic is no longer able to treat a patient’s infection, then doctors are forced to prescribe second-or third-choice drugs that may be less effective, more expensive or cause significant side effects. Research has shown that compared to typical infections, patients with drug-resistant bacterial infections have longer and more expensive hospital stays and are more likely to die from the infection. Many hospitals and health care settings are continually battling the problem of drug-resistant bacteria spreading inside their institution.

Inappropriate over-prescription and overuse of antibiotics for self-limited viral conditions, for example the common cold, is one factor driving the evolution of drug-resistance among pathogens. Another problem increasing the numbers of drug-resistant bacteria is the widespread use of antibiotics in agricultural settings. As many as two-thirds of the antibiotics purchased in the U.S. are given to poultry, cattle and swine not to treat diagnosed infections, but to promote faster growth and for routine disease prevention.

Q: “Superbugs” like MRSA (methicillin-resistant staphylococcus aureus) are invulnerable to nearly all modern antibiotics. Do superbugs possess particular qualities, or do all bacteria have this potential?

A: I believe the term “superbug” is aptly applied to a bacteria that is both pathogenic (disease-producing) and resistant to multiple first-line antibiotics. It is important to recognize that the vast majority of bacteria we encounter in our daily lives are not pathogenic.

A healthy person has 10 times more bacterial cells living in their body than human cells, and these “good citizen” bacteria participate in food digestion, vitamin production, strengthening our immune system, and taking up real estate that prevents true pathogens from gaining a foothold.

All bacteria, pathogenic and nonpathogenic, can evolve resistance to antibiotics after repeated exposure; however increasing drug-resistance in true pathogens is the true cause of alarm.

Pathogens cause disease in humans because they produce molecules known as “virulence factors.” Virulence factors cause trouble because they (a) damage or impair the function of human cells – these are also known as “toxins,” or (b) block our immune system from clearing the bacteria from the body. Staphylococcus aureus has been recognized for centuries as one of the most important human pathogens producing skin and wound infections, pneumonia, abscesses, and bloodstream infections. Once limited to hospital settings, drug-resistant MRSA strains are now circulating at epidemic levels in the community at large. In the U.S., it is currently estimated that MRSA infects 100,000 individuals killing more than 18,000. That’s more than the death toll from HIV/AIDS. Other “superbugs” may not be far behind – strains of E. coli containing a gene NDM-1 that confers resistance to nearly all useful antibiotics have appeared in hospitals in Southeast Asia and been carried by travelers to Western Europe and the United States.

Q: Bacterial resistance is a natural evolutionary response, which means traditional antibiotics inevitably become obsolete. Is there a way around this problem, another approach to fending off infection and disease without making the pathogen stronger?

A: Many infectious disease researchers, including myself, have advocated a more targeted approach to treatment of pathogens, including these drug-resistant “superbugs.” Rather than focusing only on broad-spectrum antibiotics that kill a variety pathogens but take out your good-citizen bacteria – “collateral damage” so to speak – we have studied ways to specifically block the virulence factor molecules. Here the goal is not to kill the pathogen directly, but instead to render it harmless so that your own immune system clears the infection without difficulty. Such virulence factor inhibitors could represent “magic bullets” that would not fuel the fire of the drug-resistance and could be used right alongside traditional antibiotics to treat difficult infections.

Infection occurs as a result of two things: a pathogenic bacteria and a letdown of our immune system allowing it to spread in the body. Thus I think another exciting strategy to deal with antibiotic-resistant “superbugs” is to develop new drugs that don’t target the bacteria, but rather work on the immune system side of the equation. Our white blood cells serve a front line role in killing bacteria and preventing them from spreading to cause severe disease. We are learning a lot about how white blood cells turn themselves on and off, and specific drugs that can boost their bacterial killing activities. I don’t think there is any easy way for a bacterium to evolve resistance to a superior immune system.


Religion & Ethics: Content from Across the ABC

Date/Time 24 Jul 2016 4:58:05pm
The one thing that Vaclav Klaus has not gone into in detail is the science of climate change - he therefore treats climate change an an economic issue, and misrepresents the science in the process. This is a sleight of hand to try and reframe the issue.

Scientists in Australia - in the CSIRO, BOM and the Australian Universities - have contributed a lot to the world wide knowledge on climate change. One example is the tracking of the reduction in global atmospheric oxygen levels. The decline in global atmospheric oxygen levels and the increase on CO2 are two complementary aspects of burning fossil fuels. Oxygen is used when fossil fuels are burnt and produce CO2.
The Australian Scientists are the ones we should be listening to.
They are OUR scientists - lets listen to them!


Uproar as 'Japanese Beethoven' Mamoru Samuragochi exposed as a fraud

Niigaki, a lecturer at the prestigious Toho Gakuen School of Music, said that at no stage did he believe Samuragochi was deaf, as the composer had repeatedly listened to and provided feedback on the music he contracted him to write over the years.

Samuragochi is viewed as an inspiration in Japan for having created popular classical symphonies and video game scores, despite reportedly having been completely deaf for 15 years.

Niigaki said he considered himself an accomplice in the deception. "I can't fool the people any more," he said. He said the last time he had seen Samuragochi was on December 15 last year.

But when approached by a reporter for Nippon Television, Orimoto said on camera that the firm believed Samuragochi was indeed deaf, and had a government-issued certificate which confirmed his hearing impairment."

His most popular work, "Symphony No 1, Hiroshima," dedicated to the victims of the 1945 atomic blast, became a symbol of Japanese resilience in the wake of the 2011 tsunami, after it was featured in documentary by public broadcaster NHK which portrayed the composer traveling to the disaster zone.

Daisuke Takahashi, an Olympic bronze medalist figure skater who is planning to skate to one of the works in Sochi, has also become embroiled in the saga. He issued a statement saying he had been unaware that Samuragochi was not the composer of the work, but intended to use the composition regardless.

The potential impact on Takahashi's Sochi ambitions from the controversy was a major talking point on social media, with many users complaining about the timing. Others noted that Samuragochi had built an irresistible "modern Beethoven" myth around himself that the public had lapped up.

More like Japanese Milli Vanilli...


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1.  Kinetochore–microtubule attachment throughout mitosis potentiated by the elongated stalk of the kinetochore kinesin CENP-E
Molecular Biology of the Cell  2014;25(15):2272-2281.
CENP-E kinesin harbors a highly elongated coiled-coil stalk. Using in vitro and in vivo approaches, we characterize a “Bonsai” version of CENP-E with a shortened stalk. We show that the stalk positively regulates CENP-E's motor activity, which is required for maintenance of kinetochore–microtubule attachments in both metaphase and anaphase.
Centromere protein E (CENP-E) is a highly elongated kinesin that transports pole-proximal chromosomes during congression in prometaphase. During metaphase, it facilitates kinetochore–microtubule end-on attachment required to achieve and maintain chromosome alignment. In vitro CENP-E can walk processively along microtubule tracks and follow both growing and shrinking microtubule plus ends. Neither the CENP-E–dependent transport along microtubules nor its tip-tracking activity requires the unusually long coiled-coil stalk of CENP-E. The biological role for the CENP-E stalk has now been identified through creation of “Bonsai” CENP-E with significantly shortened stalk but wild-type motor and tail domains. We demonstrate that Bonsai CENP-E fails to bind microtubules in vitro unless a cargo is contemporaneously bound via its C-terminal tail. In contrast, both full-length and truncated CENP-E that has no stalk and tail exhibit robust motility with and without cargo binding, highlighting the importance of CENP-E stalk for its activity. Correspondingly, kinetochore attachment to microtubule ends is shown to be disrupted in cells whose CENP-E has a shortened stalk, thereby producing chromosome misalignment in metaphase and lagging chromosomes during anaphase. Together these findings establish an unexpected role of CENP-E elongated stalk in ensuring stability of kinetochore–microtubule attachments during chromosome congression and segregation.
PMCID: PMC4116301  PMID: 24920822
2.  TDP-43 toxicity: the usefulness of “junk”
Nature genetics  2012;44(12):1289-1291.
Loss of the lariat debranching enzyme Dbr1 is found to repress TDP-43 toxicity. The accumulated intronic lariat RNAs, which are normally degraded after splicing, likely act as decoys to sequester TDP-43 away from binding to and disrupting function of other RNAs.
PMCID: PMC3612973  PMID: 23192178
3.  Centrosomes, chromosome instability (CIN) and aneuploidy
Current opinion in cell biology  2012;24(6):809-815.
Each time a cell divides its chromosome content must be equally segregated into the two daughter cells. This critical process is mediated by a complex microtubule based apparatus, the mitotic spindle. In most animal cells the centrosomes contribute to the formation and the proper function of the mitotic spindle by anchoring and nucleating microtubules and by establishing its functional bipolar organization. Aberrant expression of proteins involved in centrosome biogenesis can drive centrosome dysfunction or abnormal centrosome number, leading ultimately to improper mitotic spindle formation and chromosome missegregation. Here we review recent work focusing on the importance of the centrosome for mitotic spindle formation and the relation between the centrosome status and the mechanisms controlling faithful chromosome inheritance.
PMCID: PMC3621708  PMID: 23127609
4.  Sustained therapeutic reversal of Huntington’s disease by transient repression of huntingtin synthesis
Neuron  2012;74(6):1031-1044.
The primary cause of Huntington’s disease (HD) is expression of huntingtin with a polyglutamine expansion. Despite an absence of consensus on the mechanism(s) of toxicity, diminishing the synthesis of mutant huntingtin will abate toxicity if delivered to the key affected cells. With antisense oligonucleotides (ASOs) that catalyze RNase H-mediated degradation of huntingtin mRNA, we demonstrate that transient infusion into the cerebral spinal fluid of symptomatic HD mouse models not only delays disease progression, but mediates a sustained reversal of disease phenotype that persists longer than the huntingtin knockdown. Reduction of wild type huntingtin, along with mutant huntingtin, produces the same sustained disease reversal. Similar ASO infusion into non-human primates is shown to effectively lower huntingtin in many brain regions targeted by HD pathology. Rather than requiring continuous treatment, our findings establish a therapeutic strategy for sustained HD disease reversal produced by transient ASO-mediated diminution of huntingtin synthesis.
PMCID: PMC3383626  PMID: 22726834
5.  Neurodegeneration
Nature  2008;454(7202):284-285.
That mutations in the SOD1 enzyme underlie familial form of the motor neuron disease ALS is clear. But there seems to be more than one answer to the question of what are the consequences of such mutations.
PMCID: PMC3625042  PMID: 18633404
6.  Polo-like kinase 4 controls centriole duplication but does not directly regulate cytokinesis
Molecular Biology of the Cell  2012;23(10):1838-1845.
Polo-like kinase 4 (Plk4) plays an essential role in centriole duplication, but recent work led to the conclusion that Plk4 also directly regulates cytokinesis. The consequence of reduced Plk4 levels in human and mouse cells is studied. It is shown that Plk4 controls centriole duplication but does not directly regulate cytokinesis.
Centrioles organize the centrosome, and accurate control of their number is critical for the maintenance of genomic integrity. Centrioles duplicate once per cell cycle, and duplication is coordinated by Polo-like kinase 4 (Plk4). We previously demonstrated that Plk4 accumulation is autoregulated by its own kinase activity. However, loss of heterozygosity of Plk4 in mouse embryonic fibroblasts has been proposed to cause cytokinesis failure as a primary event, leading to centrosome amplification and gross chromosomal abnormalities. Using targeted gene disruption, we show that human epithelial cells with one inactivated Plk4 allele undergo neither cytokinesis failure nor increase in centrosome amplification. Plk4 is shown to localize exclusively at the centrosome, with none in the spindle midbody. Substantial depletion of Plk4 by small interfering RNA leads to loss of centrioles and subsequent spindle defects that lead to a modest increase in the rate of cytokinesis failure. Therefore, Plk4 is a centriole-localized kinase that does not directly regulate cytokinesis.
PMCID: PMC3350549  PMID: 22456511
7.  How to survive aneuploidy
Cell  2010;143(1):27-29.
Aneuploidy, or the abnormal number of chromosomes, adversely effects cell growth, but it is also linked with cancer and tumorigenesis. Now Torres et al. (2010) help resolve this paradox by demonstrating that aneuploid yeast cells can evolve mutations in the proteasome protein degradation pathway that alleviate imbalances in protein production and increase the cell’s proliferative capacities.
PMCID: PMC2955074  PMID: 20887888
8.  Long pre-mRNA depletion and RNA missplicing contribute to neuronal vulnerability from loss of TDP-43
Nature neuroscience  2011;14(4):459-468.
Cross-linking and immunoprecipitation coupled with high-throughput sequencing was used to identify binding sites within 6,304 genes as the brain RNA targets for TDP-43, an RNA binding protein which when mutated causes Amyotrophic Lateral Sclerosis (ALS). Use of massively parallel sequencing and splicing-sensitive junction arrays revealed that levels of 601 mRNAs are changed (including Fus/Tls, progranulin, and other transcripts encoding neurodegenerative disease-associated proteins) and 965 altered splicing events are detected (including in sortilin, the receptor for progranulin), following depletion of TDP-43 from mouse adult brain with antisense oligonucleotides. RNAs whose levels are most depleted by reduction in TDP-43 are derived from genes with very long introns and which encode proteins involved in synaptic activity. Lastly, TDP-43 was found to auto-regulate its synthesis, in part by directly binding and enhancing splicing of an intron within the 3′ untranslated region of its own transcript, thereby triggering nonsense mediated RNA degradation. (147 words)
PMCID: PMC3094729  PMID: 21358643
9.  Multi-classifier proteomics to define complexes yields new chromosomal proteins
Developmental cell  2010;19(3):356-359.
In a recent issue of Cell, Ohta et al. (2010) report a method of quantitative proteomics coupled with bioinformatic analysis for the identification of associated components in complex mixtures. Using this approach, they assayed the protein composition of mitotic chromosomes, identifying 4029 associated proteins, 562 of which are previously uncharacterized.
PMCID: PMC2943763  PMID: 20833356
10.  Misfolded Mutant SOD1 Directly Inhibits VDAC1 Conductance in a Mouse Model of Inherited ALS
Neuron  2010;67(4):575-587.
Mutations in superoxide dismutase (SOD1) cause amyotrophic lateral sclerosis (ALS), a neurodegenerative disease characterized by loss of motor neurons. With conformation specific antibodies, we now demonstrate that misfolded mutant SOD1 binds directly to the voltage-dependent anion channel (VDAC1), an integral membrane protein imbedded in the outer mitochondrial membrane. This interaction is found on isolated spinal cord mitochondria and can be reconstituted with purified components in vitro. ADP passage through the outer membrane is diminished in spinal mitochondria from mutant SOD1-expressing ALS rats. Direct binding of mutant SOD1 to VDAC1 inhibits conductance of individual channels when reconstituted in a lipid bilayer. Reduction of VDAC1 activity with targeted gene disruption is shown to diminish survival by accelerating onset of fatal paralysis in mice expressing the ALS-causing mutation SOD1G37R. Taken together, our results establish a direct link between misfolded mutant SOD1 and mitochondrial dysfunction in this form of inherited ALS.
PMCID: PMC2941987  PMID: 20797535
11.  Centriole duplication
Cell Cycle  2010;9(14):2731-2736.
In interphase and mitosis, centrosomes play a major role in the spatial organization of the microtubule network. Alterations in centrosome number and structure are associated with genomic instability and occur in many cancers. Centrosome duplication is controlled by centriole replication. In most dividing animal cells, centrioles duplicate only once per cell cycle at a site adjacent to existing centrioles. The conserved protein kinase Polo-like kinase 4 (Plk4) has a key role in controlling centriole biogenesis. Overexpression of Plk4 drives centrosome amplification and is associated with tumorigenesis in flies. By contrast, haploinsufficiency of Plk4 promotes cytokinesis failure, leading to an increased incidence of tumors in mice. Recent studies have shown that Plk4 is a low abundance protein whose stability is linked to the activity of the enzyme. We discuss how this autoregulatory feedback loop acts to limit the damaging effects caused by too much or too little Plk4.
PMCID: PMC3040958  PMID: 20647763
centrosome; centriole; polo-like kinase 4; Plk4; SAK; SCF; phosphodegron; β-TrCP; aneuploidy
12.  NuMA after 30 years: the Matrix Revisited
Trends in cell biology  2010;20(4):214-222.
The large Nuclear Mitotic Apparatus (NuMA) protein is an abundant component of interphase nuclei and an essential player in mitotic spindle assembly and maintenance. With its partner, cytoplasmic dynein, NuMA uses its cross-linking properties to tether microtubules to spindle poles. NuMA and its invertebrate homologues play a similar tethering role at the cell cortex, thereby mediating essential asymmetric divisions during development. Despite its maintenance as a nuclear component for decades after the final mitosis of many cell types (including neurons), an interphase role for NuMA remains to be established, although its structural properties implicate it as a component of a nuclear scaffold, perhaps as a central constituent of the proposed nuclear matrix.
PMCID: PMC3137513  PMID: 20137953
13.  Glial cells as intrinsic components of non-cell autonomous neurodegenerative disease
Nature neuroscience  2007;10(11):1355-1360.
A lesson from dominantly inherited forms of diverse neurodegenerative diseases, including amyotrophic lateral sclerosis, spinocerebellar ataxia and Huntington’s disease, is that the selective dysfunction or death of the neuronal population most at risk in each disease is not mediated solely by mutant derived damage within the target neurons. The disease-causing toxic process, which in each case is caused by mutation in a gene that is widely or ubiquitously expressed, involves mutant damage within the non-neuronal glial cells of the central nervous system - especially astrocytes and microglia. Disease mechanism is non-cell autonomous, with toxicity derived from glia as a prominent contributor to driving disease progression and in some instances even disease initiation.
PMCID: PMC3110080  PMID: 17965655
14.  A chemical tool box defines mitotic and interphase roles for Mps1 kinase
The Journal of Cell Biology  2010;190(1):21-24.
In this issue, three groups (Hewitt et al. 2010. J. Cell Biol. doi:10.1083/jcb.201002133; Maciejowski et al. 2010. J. Cell Biol. doi:10.1083/jcb.201001050; Santaguida et al. 2010. J. Cell Biol. doi:10.1083/jcb.201001036) use chemical inhibitors to analyze the function of the mitotic checkpoint kinase Mps1. These studies demonstrate that Mps1 kinase activity ensures accurate chromosome segregation through its recruitment to kinetochores of mitotic checkpoint proteins, formation of interphase and mitotic inhibitors of Cdc20, and correction of faulty microtubule attachments.
PMCID: PMC2911672  PMID: 20624898
15.  Polo-like kinase 4 kinase activity limits centrosome overduplication by autoregulating its own stability
The Journal of Cell Biology  2010;188(2):191-198.
Plk4 phosphorylates itself in trans to prevent accumulation and self-limit kinase activity, which may be important for regulating centriole duplication.
Accurate control of the number of centrosomes, the major microtubule-organizing centers of animal cells, is critical for the maintenance of genome integrity. Abnormalities in centrosome number can promote errors in spindle formation that lead to subsequent chromosome missegregation, and extra centrosomes are found in many cancers. Centrosomes are comprised of a pair of centrioles surrounded by amorphous pericentriolar material, and centrosome duplication is controlled by centriole replication. Polo-like kinase 4 (Plk4) plays a key role in initiating centriole duplication, and overexpression of Plk4 promotes centriole overduplication and the formation of extra centrosomes. Using chemical genetics, we show that kinase-active Plk4 is inherently unstable and targeted for degradation. Plk4 is shown to multiply self-phosphorylate within a 24–amino acid phosphodegron. Phosphorylation of multiple sites is required for Plk4 instability, indicating a requirement for a threshold level of Plk4 kinase activity to promote its own destruction. We propose that kinase-mediated, autoregulated instability of Plk4 self-limits Plk4 activity so as to prevent centrosome amplification.
PMCID: PMC2813471  PMID: 20100909
16.  Centromere specific assembly of CENP-A nucleosomes is mediated by HJURP
Cell  2009;137(3):472-484.
The centromere is responsible for accurate chromosome segregation. Mammalian centromeres are specified epigenetically, with all active centromeres containing centromere specific chromatin in which CENP-A replaces histone H3 within the nucleosome. The proteins responsible for assembly of human CENP-A into centromeric nucleosomes during the G1 phase of the cell cycle are now identified to be distinct from the chromatin assembly factors that load other histone H3 variants. Prenucleosomal CENP-A is complexed with histone H4, nucleophosmin 1 and HJURP. Recruitment of new CENP-A into nucleosomes at replicated centromeres is dependent on HJURP. Recognition by HJURP is mediated through the centromere targeting domain (CATD) of CENP-A, a region that induces a unique conformational rigidity to both the subnucleosomal CENP-A heterotetramer and the corresponding assembled nucleosome. We propose HJURP to be a cell cycle regulated CENP-A specific histone chaperone required for centromeric chromatin assembly.
PMCID: PMC2747366  PMID: 19410544
17.  Unattached Kinetochores Catalyze Production of an Anaphase Inhibitor that Requires a Mad2 Template to Prime Cdc20 for BubR1 Binding
Developmental cell  2009;16(1):105-117.
Premature anaphase onset is prevented by the mitotic checkpoint through production of a “wait anaphase” inhibitor(s) that blocks recognition of cyclin B and securin by Cdc20-activated APC/C, an E3 ubiquitin ligase which targets them for destruction. Using physiologically-relevant levels of Mad2, Bub3, BubR1, and Cdc20, we demonstrate that unattached kinetochores on purified chromosomes catalytically generate a diffusible Cdc20 inhibitor or inhibit Cdc20 already bound to APC/C. Furthermore, the chromosome-produced inhibitor requires both recruitment of Mad2 by Mad1 that is stably bound at unattached kinetochores and dimerization-competent Mad2. We show that purified chromosomes promote BubR1 binding to APC/C-Cdc20 by acting directly on Mad2, but not BubR1. Our results support a model in which immobilized Mad1/Mad2 at kinetochores provides a template for initial assembly of Mad2 bound to Cdc20 that is then converted to a final mitotic checkpoint inhibitor with Cdc20 bound to BubR1.
PMCID: PMC2655205  PMID: 19154722
18.  Phosphorylation of Highly Conserved Neurofilament Medium KSP Repeats Is Not Required for Myelin-Dependent Radial Axonal Growth
Neurofilament medium (NF-M) is essential for the acquisition of normal axonal caliber in response to a myelin-dependent “outside-in” trigger for radial axonal growth. Removal of the tail domain and lysine-serine-proline (KSP) repeats of NF-M, but not neurofilament heavy, produced axons with impaired radial growth and reduced conduction velocities. These earlier findings supported myelin-dependent phosphorylation of NF-MKSP repeats as an essential component of axonal growth. As a direct test of whether phosphorylation of NF-M KSP repeats is the target for the myelin-derived signal, gene replacement has now been used to produce mice in which all serines of NF-M’s KSP repeats have been replaced with phosphorylation-incompetent alanines. This substitution did not alter accumulation of the neurofilaments or their subunits. Axonal caliber and motor neuron conduction velocity of mice expressing KSP phospho-incompetent NF-M were also indistinguishable from wild-type mice. Thus, phosphorylation of NF-M KSP repeats is not an essential component for the acquisition of normal axonal caliber mediated by myelin-dependent outside-in signaling.
PMCID: PMC2782950  PMID: 19193875
neurofilaments; cytoskeleton; myelination; radial growth; motor neuron; phosphorylation
19.  Requirements for NuMA in maintenance and establishment of mammalian spindle poles
The Journal of Cell Biology  2009;184(5):677-690.
Microtubules of the mitotic spindle in mammalian somatic cells are focused at spindle poles, a process thought to include direct capture by astral microtubules of kinetochores and/or noncentrosomally nucleated microtubule bundles. By construction and analysis of a conditional loss of mitotic function allele of the nuclear mitotic apparatus (NuMA) protein in mice and cultured primary cells, we demonstrate that NuMA is an essential mitotic component with distinct contributions to the establishment and maintenance of focused spindle poles. When mitotic NuMA function is disrupted, centrosomes provide initial focusing activity, but continued centrosome attachment to spindle fibers under tension is defective, and the maintenance of focused kinetochore fibers at spindle poles throughout mitosis is prevented. Without centrosomes and NuMA, initial establishment of spindle microtubule focusing completely fails. Thus, NuMA is a defining feature of the mammalian spindle pole and functions as an essential tether linking bulk microtubules of the spindle to centrosomes.
PMCID: PMC2686415  PMID: 19255246
20.  CENP-E combines a slow, processive motor and a flexible coiled coil to produce an essential motile kinetochore tether
The Journal of Cell Biology  2008;181(3):411-419.
The mitotic kinesin centromere protein E (CENP-E) is an essential kinetochore component that directly contributes to the capture and stabilization of spindle microtubules by kinetochores. Although reduction in CENP-E leads to high rates of whole chromosome missegregation, neither its properties as a microtubule-dependent motor nor how it contributes to the dynamic linkage between kinetochores and microtubules is known. Using single-molecule assays, we demonstrate that CENP-E is a very slow, highly processive motor that maintains microtubule attachment for long periods. Direct visualization of full-length Xenopus laevis CENP-E reveals a highly flexible 230-nm coiled coil separating its kinetochore-binding and motor domains. We also show that full-length CENP-E is a slow plus end–directed motor whose activity is essential for metaphase chromosome alignment. We propose that the highly processive microtubule-dependent motor activity of CENP-E serves to power chromosome congression and provides a flexible, motile tether linking kinetochores to dynamic spindle microtubules.
PMCID: PMC2364708  PMID: 18443223
21.  Revisiting oxidative damage in ALS: microglia, Nox, and mutant SOD1
Mutation in superoxide dismutase–1 (SOD1) causes the inherited degenerative neurological disease familial amyotrophic lateral sclerosis (ALS), a non–cell-autonomous disease: mutant SOD1 synthesis in motor neurons and microglia drives disease onset and progression, respectively. In this issue of the JCI, Harraz and colleagues demonstrate that SOD1 mutants expressed in human cell lines directly stimulate NADPH oxidase (Nox) by binding to Rac1, resulting in overproduction of damaging ROS (see the related article beginning on page 659). Diminishing ROS by treatment with the microglial Nox inhibitor apocynin or by elimination of Nox extends survival in ALS mice, reviving the proposal that ROS mediate ALS pathogenesis, but with a new twist: it’s ROS produced by microglia.
PMCID: PMC2213376  PMID: 18219386
22.  Propagation of centromeric chromatin requires exit from mitosis
The Journal of Cell Biology  2007;176(6):795-805.
Centromeres direct chromosomal inheritance by nucleating assembly of the kinetochore, a large multiprotein complex required for microtubule attachment during mitosis. Centromere identity in humans is epigenetically determined, with no DNA sequence either necessary or sufficient. A prime candidate for the epigenetic mark is assembly into centromeric chromatin of centromere protein A (CENP-A), a histone H3 variant found only at functional centromeres. A new covalent fluorescent pulse-chase labeling approach using SNAP tagging has now been developed and is used to demonstrate that CENP-A bound to a mature centromere is quantitatively and equally partitioned to sister centromeres generated during S phase, thereby remaining stably associated through multiple cell divisions. Loading of nascent CENP-A on the megabase domains of replicated centromere DNA is shown to require passage through mitosis but not microtubule attachment. Very surprisingly, assembly and stabilization of new CENP-A–containing nucleosomes is restricted exclusively to the subsequent G1 phase, demonstrating direct coupling between progression through mitosis and assembly/maturation of the next generation of centromeres.
PMCID: PMC2064054  PMID: 17339380
23.  The quantitative architecture of centromeric chromatin
eLife  2014;3:e02137.
The centromere, responsible for chromosome segregation during mitosis, is epigenetically defined by CENP-A containing chromatin. The amount of centromeric CENP-A has direct implications for both the architecture and epigenetic inheritance of centromeres. Using complementary strategies, we determined that typical human centromeres contain ∼400 molecules of CENP-A, which is controlled by a mass-action mechanism. This number, despite representing only ∼4% of all centromeric nucleosomes, forms a ∼50-fold enrichment to the overall genome. In addition, although pre-assembled CENP-A is randomly segregated during cell division, this amount of CENP-A is sufficient to prevent stochastic loss of centromere function and identity. Finally, we produced a statistical map of CENP-A occupancy at a human neocentromere and identified nucleosome positions that feature CENP-A in a majority of cells. In summary, we present a quantitative view of the centromere that provides a mechanistic framework for both robust epigenetic inheritance of centromeres and the paucity of neocentromere formation.
eLife digest
The genetic information in a cell is packed into structures called chromosomes. These contain strands of DNA wrapped around proteins called histones, which helps the long DNA chains to fit inside the relatively small nucleus of the cell.
When a cell divides, it is important that both of the new cells contain all of the genetic information found in the parent cell. Therefore, the chromosomes duplicate during cell division, with the two copies held together at a single region of the chromosome called the centromere. The centromere then recruits and coordinates the molecular machinery that separates the two copies into different cells.
Centromeres are inherited in an epigenetic manner. This means that there is no specific DNA sequence that defines the location of this structure on the chromosomes. Rather, a special type of histone, called CENP-A, is involved in defining its location. Bodor et al. use multiple techniques to show that human centromeres normally contain around 400 molecules of CENP-A, and that this number is crucial for ensuring that centromeres form in the right place. Interestingly, only a minority of the CENP-A molecules are located at centromeres; yet this is more than at any other region of the chromosome. This explains why centromeres are only formed at a single position on each chromosome.
When the chromosomes separate, the CENP-A molecules at the centromere are randomly divided between the two copies. In this way memory of the centromere location is maintained. If the number of copies of CENP-A inherited by one of the chromosomes drops below a threshold value, a centromere will not form. However, Bodor et al. found that the number of CENP-A molecules in a centromere is large enough, not only to support the formation of the centromere structure, but also to keep it above the threshold value in nearly all cases. This threshold is also high enough to make it unlikely that a centromere will form in the wrong place because of a random fluctuation in the number of CENP-A molecules. Therefore, the number of CENP-A molecules is crucial for controlling both the formation and the inheritance of the centromere.
PMCID: PMC4091408  PMID: 25027692
centromere; CENP-A; epigenetics; molecular counting; quantitative microscopy; histone variant; human
24.  Catalytic Assembly of the Mitotic Checkpoint Inhibitor BubR1-Cdc20 by Mad2-induced Functional Switch in Cdc20
Molecular cell  2013;51(1):92-104.
The mitotic checkpoint acts to maintain chromosome content by generation of a diffusible anaphase inhibitor. Unattached kinetochores catalyze a conformational shift in Mad2, converting an inactive open form into a closed one that can capture Cdc20, the mitotic activator of the APC/C ubiquitin ligase. Mad2 binding is now shown to promote a functional switch in Cdc20, exposing a previously inaccessible site for binding to BubR1’s conserved Mad3 homology domain. BubR1, but not Mad2, binding to APC/CCdc20 is demonstrated to inhibit ubiquitination of cyclin B. Closed Mad2 is further shown to catalytically amplify production of BubR1-Cdc20 without necessarily being part of the complex. Thus, the mitotic checkpoint is produced by a cascade of two catalytic steps, an initial one acting at unattached kinetochores to produce a diffusible Mad2-Cdc20 intermediate and a diffusible one in which that intermediate amplifies production of BubR1-Cdc20, the inhibitor of cyclin B ubiquitination by APC/CCdc20.
PMCID: PMC3713096  PMID: 23791783
25.  Microtubule capture by CENP-E silences BubR1-dependent mitotic checkpoint signaling
The Journal of Cell Biology  2005;170(6):873-880.
The mitotic checkpoint is the major cell cycle control mechanism for maintaining chromosome content in multicellular organisms. Prevention of premature onset of anaphase requires activation at unattached kinetochores of the BubR1 kinase, which acts with other components to generate a diffusible “stop anaphase” inhibitor. Not only does direct binding of BubR1 to the centromere-associated kinesin family member CENP-E activate its essential kinase, binding of a motorless fragment of CENP-E is shown here to constitutively activate BubR1 bound at kinetochores, producing checkpoint signaling that is not silenced either by spindle microtubule capture or the tension developed at those kinetochores by other components. Using purified BubR1, microtubules, and CENP-E, microtubule capture by the CENP-E motor domain is shown to silence BubR1 kinase activity in a ternary complex of BubR1–CENP-E–microtubule. Together, this reveals that CENP-E is the signal transducing linker responsible for silencing BubR1-dependent mitotic checkpoint signaling through its capture at kinetochores of spindle microtubules.
PMCID: PMC2171436  PMID: 16144904

Results 1-25 (81)


A Mathematical Structure of Simple Defensive Network Deceptions

Copyright (c) 1999 Fred Cohen

Background and Introduction

In the last year, deception has emerged as one of the emerging techniques for effective information protection [Cohen98] [Drill-Down] in networks. A natural side effect of the use of this technology is the desire to understand the mathematical properties underlying its utility. In the above cited paper, several informal notions were introduced - to wit:

In this paper, we will examine these claims and provide a more mathematical foundation for this aspect of deception as a tool for network defense.

Basic Properties of Deceptive Network Defense

There are an unlimited number of ways that deception may be used for defense. Our analysis is primarily focussed on the information theoretic notion of altering the information content [Shannon48] [Overview Drill Down] gained by intelligence efforts and the workload [Shannon49] [Overview Drill Down] associated with attacking and defending systems. These notions are somewhat different for deception than for cryptography, but conceptually, they are quite similar.

Underlying the notion of using deception for network defense is the model of an enemy who believes that information systems are vulnerable and has finite resources with which to attack them. This model would seem to imply an attack process whereby an intelligence effort is used to try to find vulnerabilities and a technical capability is used to try to exploit the vulnerabilities identified by the intelligence effort.

Even if there were a perfect defense in place, which most experts believe to be impossible, the perception of the enemy that imperfections exist and that their exploitation can affect the outcome of the conflict is key to the notion of the enemy attempting attacks. If the enemy does not believe there is an exploitable weakness, no attack will be forthcoming. Thus, we have the potential for a deception that induces the belief in the enemy that there exists and exploitable weakness of value. The goal of this deception would then be to trick the enemy into misallocating resources.

Today, the reality is that there are such weaknesses in every system of value, and all parties believe this to be the case, so the next level of deception is to try to defeat the enemy's attack process. Assuming that the enemy is technically competent and that there are real vulnerabilities, the proper identification of those vulnerabilities by the enemy's intelligence effort will yield a successful attack. Thus, the defensive deception process is and must be oriented toward defeating the enemy's intelligence process. Other aspects of the defense process, such as prevention techniques, are oriented toward eliminating the technical vulnerabilities, the ability of the enemy to exploit them, or their impacts.

Figure 1 - The Structure of Defensive Network Deception

Figure 1 shows the basic structure of deceptive defense. There are a potentially infinite number of possible attack techniques, and the enemy intelligence effort is directed toward finding a sequence of techniques that will be effective at achieving their goals. The defender's objectives are not necessarily at odds with this, in that the defender's strategic defense needs may not conflict with the enemy's strategic attack needs. We are thus not in a 'zero sum game'. Nevertheless, we will assume for the purposes of our discussion that the objective of the defender is to defeat the attacker's intelligence process without undue consumption of defensive resources. In other terms, the goals are to:

Given an initial set of beliefs about the defender's system, the goal of the attacker's intelligence effort is to reduce the uncertainty about what is present in the defender's systems to the point where technical attack has a high likelihood of achieving success. This is Shannon's notion of increasing information content directed toward the defender's systems. The ideal deceptive defense allows this process to proceed in such a manner that the attacker's intelligence effort appears to meet expectations without being too easy or in any other way tipping the attacker's hat. In other words, the attacker moves toward increased certainty at an appropriate rate, but the content the attacker achieves is to the defender's advantage. Over the long run, the successful defense will induce the attacker to believe that the technical attacks were successful and that some other circumstance was the cause of the ultimate failure of the overall strategy.

A classic example of a successful defense of this sort is the deception program carried out in World War II prior to the Normandy landings. In one case, British intelligence created a set of fictions surrounding the landings that fooled Hitler even after the landings took place. It was several days before he figured out that the real landings weren't a feint to cover up other landings, and by that time it was too late.

The present work is, unfortunately, not matured to the point of being able to describe this level of long-term success. For that reason, we will confine ourselves to the task of detecting each individual 'attack sequence' and making the aggregate of a large number of attack sequences unfruitful for the enemy. Thus, our goals are:

From Honey Pots to the Deception ToolKit

Early 'honey pot' systems (Figure 2) were based on the idea of placing a small number of attractive targets in locations where they are likely to be found, and drawing attackers into them.

Figure 2 - Early Honey Pot Systems

The challenge in these systems from an intelligence viewpoint is to find a way to influence the opponent to concentrate their intelligence efforts against the honey pot over other systems. This challenge is relatively easy to meet against some classes of threats, such as typical Internet-based Web site defacers who look in advertised locations for high profile systems to attack. It is also effective as a system to 'switch' an attacker to once an attack attempt has been detected. Unfortunately, for even a mildly advanced intelligence activity, this type of defense offers little in the way of effective influence because it consumes such a small portion of the overall intelligence space and has little effect on altering the characteristics of the typical intelligence probe.

Figure 3 - The Original Deception ToolKit

The original Deception Toolkit (DTK) provided some relief from the low probability of encountering a deception and the extreme localization of deceptions under previous honey-pot systems (see Figure 3). Under DTK, deceptions are spread among the normal systems in a network in such a way that unused services on those systems are consumed with deceptions. This has two effects. One effect is that it spreads the deceptions over a larger portion of the IP/port address space, a similar effect to Shannon's 'diffusion' used in cryptographic systems. The other effect is that increases the percentage of deceptions in the environment, thus increasing the likelihood of an intelligence probe encountering a deception rather than a vulnerability. (see Figure 4)

Figure 4 - From Honey Pots to DTK

While DTK was an improvement in some sense over previous honey-pots, there are a lot of limitations in the DTK model of deception. In particular, (1) DTK had no affect on the overall search space for the intelligence effort, (2) provides only a relatively poor quality of deception, and (3) only nominally increases the sparsity of vulnerabilities in the search space. But perhaps a far more serious flaw in DTK is that it is only really effective against probes at a distance. If an attacker has gotten part of the way into a network and is willing and able to engage in observation rather than active probing, the real services will rapidly become apparent. For this reason, while DTK is effective against more of the current threats in the current environment than honey pots, it is unlikely to be effective at influencing opponent choices where that opponent has a more advanced intelligence capability.

Increasing the size of the Search Space and the Sparsity of Real Vulnerabilities

One way to improve the situation for the defender is to increase the intelligence workload by increasing the size of the search space. This can be done in fairly trivial ways, but the results will also be fairly trivial to defeat by skilled intelligence groups. Still, any improvement 'raises the bar' for some - perhaps most - of the attackers.

Figure 5 - Multiple Deceptions in a Single Box

Using the multi-homed capabilities of most modern computer systems, a single Ethernet card can act as the host for numerous IP addresses, each optionally having their own MAC address as well. This technique can be applied for deception by filling a large address space that would normally be sparsely populated so that it is less sparsely populated, or perhaps even fully populated, depending on your goals and your adversary. The cost of this technique is very low. In practice, we have been able to place more than 4,000 IP addresses on a single PC running Linux, which means that with 16 $500 computer systems and about $500 worth of connecting cables and Ethernet hubs (for a total of only $8500 worth of hardware) we can do a deception that covers all of the IP addresses in a class B IP network (a.b.*.*).

Making these deceptions convincing is somewhat more complex, as we will go into a bit later, however, from a simplistic viewpoint, placing services on all of these IP addresses increases the workload of the intelligence effort in determining which of these systems are legitimate and which are not. In particular, we have used DTK to populate more than 40,000 IP addresses with false services. While the deceptions are relatively easy to spot, they are highly effective in causing the intelligence workload to go up, in increasing the time to attack, and decreasing the odds of certain classes an intelligence probes going undetected.

When a probe encounters a false service, with proper access to outside routers, we are also able to redirect all traffic into deceptions so that subsequent remote access is deception from that point forward. The conditions under which switchovers occur and what services are switched over in what conditions are held confidential because revealing them would lead to an attack in which any single known valid service that could be easily differentiated from a deception could be used to test whether the intelligence probe had been detected and responded to. The sophisticated intelligence effort would then switch to another source location and continue the search.

Figure 6 - From DTK to D-Wall - Part 1

If we look more deeply into this feedback mechanism we can determine a level at which the IP address space is exhausted before the probability of a meaningful intelligence probe gets high enough to be of concern. This is done by the following process:

1) Set RS = the number of real services. (example 1,000)
2) Set DS = the number of deception services. (example 1,000,000)
3) Set RRD = RS/DS - the ration of real services to deceptions. (example 1/1,000 = 0.1%)

The initial probability of encountering a real service is RRD (0.1%). For each failed probe that is detected by the attacker, assume a new IP address must be used to continue probing. For each failed probe, only the specific service on the specific IP address can be eliminated from probing. This on the second try, the new value of RRD is given by RS/(DS-1). After 100,000 probes, the probability reaches RS/(DS-100,000) or (1,000/900,000) or 0.11%. Depending on various conditions, different assumptions can be made and the computation becomes more complex, but the notional result is that the resource requirement to gain meaningful intelligence via random probes is extremely high.

Of course the reason we call these things intelligence probes is that the opponent is taken to be intelligent. A more intelligent approach might be for an attacker to assume that they will first identify machines with seemingly legitimate Web servers and not search for every other service. Assuming that there are 50 such machines out of 50,000 IP addresses and that all other conditions specified above remain the same, the first probe still yields a 0.1% chance of success, but after 50,000 probes, all 50 of the legitimate web services have been identified. This is less than one attempt from every IP address in a class B network, which we know we can easily simulate using the same deception technology as the defender with only a single machine which flexes IP addresses as needed for the attack.

In the attack, countermeasure game, there is no end to the process, but we will take it a step further to give a real sense of how far we can go with this level of deception. Suppose that the defender correlated IP addresses of historical intelligence probes and, after 10 tries from different IP addresses in a class C network or 100 tries from different IP addresses in a class B network, switched the entire networks to deceptions. In this case, the probe above would be limited to 100 tries per class B network, so that in order for the attacker to identify all 50 Web servers, it would require the use of 50,000 IP addresses in 5,000 class C networks or 500 class B networks.

After determining that this sort of deception is in place, a stronger intelligence effort would not concentrate on some sort of random probing. Instead, the effort might concentrate on a more fruitful, and more expensive process, such as following existing 'known-good' paths into the infrastructure, planting insiders who can probe with far more knowledge in hand, and so forth. Countering these intelligence attempts requires a different deception advancement.

Enhancing the Quality of Deceptions

A technical advancement we have recently explored in this arena is to try to give the deceptions far higher quality so that it is very hard to differentiate a legitimate service from a deception. Some of the areas we have explored include; (1) producing simulated traffic so that traffic analysis will not be able to detect deceptions, (2) reconfiguring the deception network over time to emulate the manner in which a normal network changes over time, (3) creating organizational deceptions that support the technical deceptions, and (4) using real systems for deceptions instead of finite state machines as are used in DTK.

Figure 7 - Multiple Address Translation

The technique shown in Figure 7 uses multiple address translation to provide the means for far higher quality in deceptions than was previously available, and does so at a very low relative cost. The basic notion is to redirect selective services - a proxy service if you will - where DTK used to handle the service directly - but rather than a simple proxy service, this service does address translation so that the same source and destination addresses remain in the deception system as were in place in the original system. In figure 7, a user from m.n.o.p enters at the interface to a.b.c.g and is redirected through a sequence of address translations to a.f.c.g which transmits from 10.n.o.p toward 10.g.c.f and finally, the last translation has the packet going from the deception version of m.n.o.p to the deception version of a.b.c.g. Another example in Figure 7 has more than two address translations (i.e., w.x.y.z eventually becomes k.l.n.q).

Figure 8 - from DTK to D-Wall - Part 2

This mechanism can be used for a wide variety of purposes, including flexing the translation mechanisms over time for diffusion of data through multi-hop anonymizer services, tunneling traffic through intervening infrastructures, and creating multiple deceptions based on source and destinations. In the case of enhanced deception quality, we can use this method to associate deception services to the same machine type and configuration as the real services thus dramatically increasing the realism associated with the deception.

Summary and Conclusions

The set of techniques introduced in this paper address two major impediments to effective deception against high quality technical intelligence efforts; (1) address aliasing, and (2) multiple address translation. By combining these technological advances with a more advanced approach to deception, we can dramatically increase the complexity of the technical intelligence process against networked information systems with relatively little increase in cost.

[Cohen98-1] F. Cohen, A Note on the Role of Deception in Information Protection , Computers and Security 1999. [ This paper concentrates on the role of deception in information protection, and as such, its main focus is on addressing different perspectives on deception. We begin by examining the historical use of deception for information protection in more depth, consider the moral issues associated with the use of deception for protection, and examine techniques for deceptive defense and complexities in their use. Next we describe theoretical issues behind the use of deception in the Deception ToolKit (DTK), practical results on the use of DTK in the Internet and in an experimental environment, and notions about the widespread use of DTK and similar tools. Finally, we summarize results, draw conclusions, and discuss further work.] [Drill-Down]

[Shannon48] C. Shannon, A Mathematical Theory of Communications, Bell Systems Technical Journal. 3, no. 27, (July 1948). [This is perhaps the most famous and seminal paper in the information sciences. In this paper, Shannon described the first practical syntactic information theory, which formed the basis for a vast array of developments in the information sciences from the design of computer instruction sets to the integrity of satellite communications and beyond. It is hard to overestimate the impact of this work.] [Overview Drill Down]

[Shannon49] C. Shannon, Communications Theory of Secrecy Systems, Bell Systems Technical Journal (1949):656--715. [In this paper, Shannon applied his information theory to breaking all of the known ciphers up till that date and provided a proof that the only theoretically unbreakable cryptosystem was the so-called perfect cipher. This paper also introduced the concepts of diffusion and confusion, and introduced the concept of work load which is the basis for using imperfect cryptosystems today.] [Overview Drill Down]


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LEVELS of happiness and emotional wellbeing among Glaswegian adolescents have plunged so far they have pulled the whole of Scotland into a happiness "deficit".

An expert in the mental wellbeing of young people, whose report identified the problem, suggests the economic downturn may be to blame for the phenomenon.

Recent years have seen a reversal of gains made in previous years, which had seen levels of happiness reported by young Scots rising steadily.

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Katy Levin, senior researcher within public health for NHS Greater Glasgow and Clyde, said: "The happiness and confidence of young people in Scotland increased every four years, from 1992 to 2006, but dropped between 2006 and 2010. The rest of Scotland plateaued, but the reductions were so great in Glasgow this caused the whole of the country to fall.

"I would suggest this is because of the recession, which affected Glasgow more than anywhere else in Scotland."

Ms Levin has just published a report on her findings. She explained that although the 15 to 16 year-olds who were interviewed for her survey may not have been directly hit by job losses or changes to the welfare system, they still may have been affected by them: "If there is job insecurity or that type of pressure in the home, it is bound to put a lot of pressure on families.

"If someone loses their job, or their job has been threatened, this would put a tremendous pressure on relationships and put a stress over the household."

The report, No Mean City, examines why Glaswegian adults have the worst health in Scotland while the health of young people is similar to those in the rest of the country, by comparing the behaviours of adolescents in Glasgow with those in the rest of Scotland. This stage of life is seen as pivotal in determining the long-term behaviour of an individual.

Ms Levin explained: "Adolescence is a very important time as it is when people become independent and start to make their own choices. If a bad choice is made as a young person, such as smoking, then they are more likely to be a smoker into adulthood. Making other choices, such as sitting exams or who your peer group is, all have a great influence into adulthood."

Surprisingly, although smoking and drinking are major elements in the poor health of the city's adult population, the research discovered these habits were less prevalent in young people in Glasgow than elsewhere in the country. But aggressive behaviour, poor diet and sedentary behaviour were more common in this city than the rest of Scotland.

Ms Levin suggests more focus could be placed on reducing the inactivity of young Glaswegians, which tends to be overlooked as a factor in unhappiness in favour of initiatives promoting physical activity or improving diet.

"One of the key targets should be to reduce sedentary behaviour as well as increasing physical activity to combat obesity, although it is particularly difficult. You could play basketball for an hour, then sit on your computer for four hours, and that won't be overcome by the physical activity."

She notes the causes of sedentary behaviour, watching television, playing a games console or sitting on the computer generally occur in the home and suggests parents could be more aware of this but understands the difficulty of breaking habits: "If parents ask other parents how long their children play computer games and they discover the whole community is spending hours on games, then it becomes the norm.

"However it is important to get the message across that sedentary behaviour is not a good thing."

Co-author David Walsh, from the Glasgow Centre of Population Health, believes research into the health of adolescents could help unlock why life expectancy in Scotland is the lowest in Western Europe, the difference most markedly pronounced amongst those of working ages. He said: "This is important research into the life course; how health changes from childhood through to adolescence and then adulthood.

"It is important young people get the message of good health behaviours but it should be done in tandem with creating an environment that allows that to happen.."


Armed police officer charged with murder over Azelle Rodney shooting

A decorated former Scotland Yard marksman involved in a botched armed operation against a drugs gang was charged yesterday with murdering one of the suspects.

Known only as E7, he is just the third officer in the last two decades to be charged with murdering a suspect in the line of duty.

The officer was charged after a public inquiry found last year that the decision to fire two fatal bursts of gunfire at Azelle Rodney nine years ago was irrational and without “lawful justification”.

Mr Rodney, 24, was killed after undercover police teams rammed a car carrying him and two others who were believed to be on their way to rob a group of Colombian drug dealers of a stash of cocaine. The officer had been due to provide cover for his colleagues during the operation and told the inquiry that he believed Mr Rodney had picked up a gun and was about to use it.

The prosecution comes eight years after the Crown Prosecution Service had previously declined to charge the officer after an investigation by a watchdog which found nothing to criticise in the police operation.

“I am very pleased at the CPS’s decision to prosecute the officer who killed my son,” said the dead man’s mother Susan Alexander. “I have waited a long time to see this day and hope this prosecution will lead to justice for Azelle.”

Suspects of crime are normally named when they are charged but the now-retired officer was given anonymity before he gave evidence at the 11-week inquiry into the fatal shooting. The inquiry heard that the officer had lawfully previously shot four people, including two fatally, during the 1980s and had been commended for bravery for his role in arresting an armed man.

The head of the inquiry, Sir Christopher Holland, found that E7 had changed his story and there was little or no justification for seven of the eight shots that he fired within two seconds.

“I have to find that there was no lawful justification of shooting Azelle Rodney so as to kill him,” the report said. In relation to the four fatal shots, Sir Christopher concluded: “I am wholly satisfied that firing so as to kill him … was disproportionate and therefore unreasonable and unlawful.”

Backed by Scotland Yard and the Police Federation, the officer went to court to challenge the finding that the shooting had been “irrational” but lost his case. The Federation indicated it would continue to pay the officer’s legal expenses when the case went to court. The former officer declined to comment through his solicitor.

Alison Saunders, the Director of Public Prosecutions, said: “We have carefully considered the new file of evidence submitted to us and have decided that a former Metropolitan Police officer, currently identified only as E7, will be prosecuted for murder. We have determined that there is a realistic prospect of conviction and that a prosecution is in the public interest.”

The family said that it was disappointed that prosecutors did not support a prosecution against the force because of failures over the planning and oversight of the operation on April 30, 2005.

Sir Christopher reported there had been a “systemic failure of communication” between the firearms team and senior officers running the operation, and opportunities were missed to arrest Mr Rodney before his car was stopped outside a packed pub in north London. “Due to the active legal proceedings against E7, we are unable to provide further reasoning for our decisions at this stage,” said the CPS.


Russia braces for IOC Rio ruling

2016-07-22 15:05

Russia insists it expects to avoid a blanket ban from the IOC on its competitors at the Rio Olympics.

Russia lashes out at CAS doping appeal rejection

2016-07-21 14:27

Russia has slammed a ruling by CAS to reject an appeal against a ban for doping that will see the track and field team miss the Rio Games.

CAS rejects Russia Olympic ban appeal

2016-07-21 11:53

The IAAF has welcomed CAS's rejection of Russia's doping appeal, declaring the ruling "has created a level playing field for athletes".

Russia to learn Rio fate 'within a week'

2016-07-20 14:41

The IOC will decide "within seven days" on whether to ban Russia from the Rio Games over rampant state-orchestrated doping.

2 Russian weightlifters banned for doping

2016-07-20 12:18

Two Russian weightlifters have been banned for doping in a further hit to the credibility of both Russian sport ahead of the Rio Olympics.

IOC ban Russian sports minister from Rio

2016-07-19 17:48

The IOC has barred Russian Sports Minister Vitaly Mutko and other ministry officials from attending the Rio Games.

Russia's Rio status hangs by thread

2016-07-19 13:36

The International Olympic Committee is holding emergency talks to decide Russia's status for the Rio Olympics.

Russia says 68 athletes asked to compete in Rio

2016-07-05 15:08

Russia's athletics federation published a list of 68 athletes who have formally requested to be allowed to compete in Rio.

Russia in final plea to IOC over athletes' ban

2016-06-21 17:50

Russia has a zero tolerance policy on doping, saying the "unfair" IAAF ban meant its athletes were "punished for the sins of others".

Russia's doping ban won't affect Paralympians

2016-06-20 18:08

The International Paralympic Committee says Russia's doping ban from athletics won't affect them from competing in the Rio Games.

Russia facing calls for all-out Rio ban

2016-07-22 12:53

Russia is facing calls to be kicked out of the Olympics after their track and field squad lost their appeal over being banned for state-sponsored doping.

3 Russian stars who will miss Rio Games

2016-07-21 13:59

Three Russian star athletes who will miss the Rio Olympics after CAS dismissed an appeal against a ban on Russia's track and field team.

Key court ruling as IOC weighs Russia's Rio fate

2016-07-21 11:09

CAS is to rule on an appeal by 68 Russian athletes barred from the Rio Games, as the IOC debates a blanket ban on Russia.

Timeline of Russian doping scandal

2016-07-20 14:20

A look at a timeline of Russian doping and corruption scandals after the IOC will look into legal options to keep the country from competing in Rio.

IOC studying 'legal options' on Russian ban

2016-07-19 19:02

The IOC will study "legal options" before deciding whether to ban Russia from the Rio Olympics.

4 Russian officials suspended over doping saga

2016-07-19 16:43

Russia's sports minister suspended four more officials over allegations of state-run doping as the IOC could ban them from the Rio Games.

Mouse hole and 'magicians' - how Russia doped

2016-07-19 10:04

A discreet "mouse hole" through a wall, hid tampered samples had night-time visits by Russian secret service agents dubbed "the magicians".

France expels Russian football fan leader for second time

2016-06-22 11:36

Russian football activist Alexander Shprygin was expelled by France for the second time in four days.

Defiant Russian athletes react to doping ban

2016-06-21 08:04

With Russia's athletes now banned from the Rio games, excitement for competition has been replaced by despair and defiance.

New drug claims rock Russia

2016-06-16 08:30

Hundreds of attempts to carry out drug tests on Russian athletes this year have been thwarted, the World Anti-Doping Agency (WADA) claims.

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In 1975, physicist Kip Thorne and astronomer Anna Żytkow proposed that there are hybrids of red supergiant and neutron stars that superficially resemble normal red supergiants, such as Betelguese in the constellation Orion, but differ in their distinct chemical signatures that result from unique activity in their stellar interiors.

These Thorne-Żytkow objects (TŻOs) were hypothesized to be formed by the interaction of two massive stars ― a red supergiant and a neutron star formed during a supernova explosion ― in a close binary system. While the exact mechanism is uncertain, the most commonly held belief is that, during the evolutionary interaction of the two stars, the much more massive red supergiant essentially swallows the neutron star, which spirals into the core of the red supergiant.

While normal red supergiants derive their energy from nuclear fusion in their cores, these TŻOs would probably powered by the unusual activity of the absorbed neutron stars in their cores.

Now we may have find out. The first Thorne-Żytkow object has been discovered.

Teff vs. measured line ratios for our sample of SMC targets. The ratios include features that we expect to be enhanced in TZOs (a) as well as our ‘control’ features (b). A dark grey line shows the best linear fit for each line ratio as a function of Teff, while the light grey lines mark the 3σ
deviations from the fit that should encompass 99.7 per cent of a normally distributed sample. Ratios measured in our spectrum of HV 2112 are plotted in red. Error bars for each point illustrate the systematic errors of .5 per cent in our equivalent width measurements. Credit:

Project leader Emily Levesque of the University of Colorado Boulder, said, "Studying these objects is exciting because it represents a completely new model of how stellar interiors can work. In these interiors we also have a new way of producing heavy elements in our universe. You've heard that everything is made of 'star stuff'—inside these stars we might now have a new way to make some of it."

Preprint: Emily M. Levesque, Philip Massey, Anna N. Zytkow, Nidia Morrell, 'Discovery of a Thorne-Zytkow object candidate in the Small Magellanic Cloud', arXiv:1406.0001. Source: University of Colorado at Boulder