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Recent News and Articles on the Keywords: new + holes + black  Related to the article below (Last Update: 8/5/2008)

CDC study reveals gaping holes, unanswered questions
The Daily Voice, NY -
The study concludes that Black Americans made up at least 45 percent of new infections in 2006. Given that finding, it must now be the CDC's most urgent ...
Black Hat/DefCon: Welcome to the Funhouse
Washington Post, United States -
Rootkits will be a hot topic at Black Hat as some of the world's foremost researchers on the subject reveal new discoveries they've made about subverting ...
You can take these science books to the beach
USA Today -
He takes readers on a tour ? not skipping the stories of how scientists really joust over ideas ? of the brawl over whether black holes truly destroy matter ...
Bright flares emitted by mangled stars could reveal ejected black ...
Thaindian.com, Thailand - Aug 3, 2008
When two supermassive black holes collide, one or both may be hurled from the centre of the galaxy. Some such recoiling black holes can be detected by their ...
Absence of Tiger makes Tour a safer place for all
Irish Times, Ireland - 57 minutes ago
Well, the sight of a very large black bear looking even more bemused than some competitors on the 13th hole at the Broadmoor golf club in Colorado Springs ...
Black Knights set to run no-name offense
Times Herald-Record, NY -
"I'm starting to get there, just making the reads and what holes open up." Army ran about two or three option plays in '07. Ironically, it was Mooney who ...
On a flight to Mexico, passenger is detoured into 'black hole'
Albany Times Union, NY -
To get the next flight, he'd have to buy a new $275 ticket; he managed to argue his way down to $150. It's money Tick's father doggedly tried to recover, ...
BSN Interviews Bobby Seale, the Black Panther founder
RushPRnews.com (press release), Canada -
BSN: What do you think of the New Black Panthers? Their philosophy strikes me as being totally different from yours. BobbyS: Thumbs down! ...

Los Angeles Times
Recalling Al Campanis' 'Nightline' nightmare
Los Angeles Times, CA -
When Ted gave Campanis a chance to dig himself out of a hole, Campanis asked, "Why are black men or black people not good swimmers? ...

Brisbane Times
'Dingo' Deans says move on
The Australian, Australia - Aug 3, 2008
As captain Stirling Mortlock noted, the harder the Wallabies tried, the deeper they dug themselves into a hole. Nonu's bonus point try after the siren ...
All Blacks throw down the gauntlet SuperSport
N Zealand 39 Australia 10 TeleText
Wallabies lick wounds ahead of South Africa trip LIVENEWS.com.au
iAfrica.com
all 481 news articles »
Source: Google News

[BOOK] Black Holes, White Dwarfs and Neutron Stars: The Physics of Compact Objects -
SL Shapiro, SA Teukolsky - 1983 - osti.gov
... above neutron drip; Pulsars; Accretion onto black holes; Supermassive stars and
black holes; Appendices; and ... Publisher, John Wiley and Sons Inc.,New York, NY. ...

[BOOK] Black Hole Physics: Basic Concepts and New Developments -
VP Frolov, I Novikov - 1998 - books.google.com
... new generation re- quired developments in numerical relativity and anatytieai^neihnds
for the analysis of the gravitational radiation generated by black holes. ...

… and Timing Behavior of the Black Hole Candidate XTE J1550-564: A New Interpretation of Black Hole … -
J Homan, R Wijnands, M van der Klis, T Belloni, J … - The Astrophysical Journal Supplement Series, 2001 - UChicago Press
... Correlated X-Ray Spectral and Timing Behavior of the Black Hole Candidate XTE
J1550-564: A New Interpretation of Black Hole States. Jeroen Homan,1. ...

Black holes from cosmic rays: Probes of extra dimensions and new limits on TeV-scale gravity -
LA Anchordoqui, JL Feng, H Goldberg, AD Shapere - Physical Review D, 2002 - APS
Black holes from cosmic rays: Probes of extra dimensions and new limits on
TeV-scale gravity. Luis A. Anchordoqui 1 , Jonathan L. Feng ...

Black hole explosions? -
SW Hawking - Nature, 1974 - nature.com
... Hawking, SW, in Black Holes (edit. by de Witt, CM, and de Witt, B. S), Les Houches
Summer School, 1972 (Gordon and Breach, New York, 1973). ...

Extending the lifetime of 3D black hole computations with a new hyperbolic system of evolution … -
LE Kidder, MA Scheel, SA Teukolsky - Physical Review D, 2001 - APS
... formulation significantly effects the numerical solution of the evolution equations,
we perform numerical evolutions of single black holes using a new 3D code ...

New black hole solutions with hair -
S Droz, M Heusler, N Straumann - Physics Letters B, 1991 - Elsevier
... (The energy density of the matter field decays rapidly.) Therefore, the new "Skyrme
black holes" provide counter examples to the "no hair" conjecture. ...

New connections between 4D and 5D black holes -
D Gaiotto, A Strominger, X Yin - JHEP, 2006 - iop.org
... February 8, 2006 New connections between 4D and 5D black holes Davide Gaiotto, *
Andrew Strominger* and Xi Yin* Center of Mathematical ...

Charged black holes in string theory -
D Garfinkle, GT Horowitz, A Strominger - Physical Review D, 1991 - APS
... For the charged black holes one finds 2 2e2i0 D= Q (10) This contrasts with the ... that
the scalar charge must vanish.6 However, D is not a new free parameter in ...

Particle creation by black holes -
SW Hawking - Communications in Mathematical Physics, 1975 - Springer
Commun. math. Phys. 43, 199--220 (1975) @ by Springer-Verlag 1975 Particle Creation
by Black Holes ... a[ for the Page 3. Particle Creation by Black Holes 201 ...

Source: Google Scholar
 

New technology enables astronomers to detect two supermassive black holes in colliding galaxies

UCR's Gabriela Canalizo helped use 'adaptive optics' to compensate for atmospheric blurring

RIVERSIDE, Calif. -- Astronomers, including UC Riverside’s Gabriela Canalizo, have used powerful adaptive optics technology at the W. M. Keck Observatory in Hawai‘i to reveal the precise locations and environments of a pair of supermassive black holes at the center of an ongoing collision between two galaxies 300 million light-years away.

The new observations of the galaxy merger known as NGC 6240 reveal that each of the black holes resides at the center of a rotating disk of stars and is surrounded by a cloud of young star clusters formed in the merger.

Study results appear online in Science Express today; in print in Science at a date to be determined.

Article continues below and (thank you)

 

"The study of the interplay between galaxy mergers, star formation, and activity from accreting black holes is crucial to our understanding of how the universe evolved to the galaxies and structures we see today," said Canalizo, an assistant professor of physics in UCR’s Institute of Geophysics and Planetary Physics.

Canalizo, the second author of the research paper, worked with Claire E. Max, the paper’s lead author, as a postdoctoral researcher at Lawrence Livermore National Laboratory (LLNL) from 2000 to 2003. Willem H. de Vries, a physicist at LLNL and UC Davis, is also a coauthor.

"NGC 6240 is a system of a pair of galaxies caught in the act of merging," said Canalizo, who is also a faculty member in the Department of Physics and Astronomy at UCR. "It presents an ideal lab for study and for testing our current models of galaxy evolution. It exhibits not only accreting black holes, also called active galactic nuclei, but also prodigious star formation, and a galaxy merger in progress. Moreover, the two black holes are in the process of merging and the system is very close to us, making it easier to observe in detail. At about 300 million light years away, NGC 6240 might as well be in our backyard, compared to the majority of active nuclei in the universe."

Previous studies had already discovered the presence of the two active galactic nuclei. "People had observed this pair of colliding galaxies at different wavelengths and seen what they thought were the black holes, but it's been very hard to make sense of how the observations at various wavelengths correspond to each other," said Max, a professor of astronomy and astrophysics at UC Santa Cruz and the director of its Center for Adaptive Optics. "The adaptive optics results enabled us to tie it all together, so now we can really see it all – the hot dust in the infrared, the stars in the visible and infrared, and the X-rays and radio emissions coming from right around the black holes."

Adaptive optics (AO) is a system comprised of telescopes, computers and deformable mirrors. It enables astronomers to counteract the blurring effects of turbulence in Earth's atmosphere, which degrades images seen by ground-based telescopes.

"Using AO, we were able to pinpoint the exact location of the active nuclei within the two galaxies," Canalizo said. "This will allow us, for the first time in this system, to study and model the interaction between the accreting black holes and the star formation around them. It turn, this will give us clues to how galaxies assemble from smaller units to the galaxies we see today."

Images of NGC 6240 in visible light from the Hubble Space Telescope show the outer parts of the colliding galaxies distorted by their ongoing merger into long tidal tails of stars, gas, and dust. In the bright central region, two distinct nuclei can be discerned, but clouds of dust obscure much of the visible light from the core. The presence of two supermassive black holes in NGC 6240 was first demonstrated by X-ray observations from NASA's Chandra X-ray Observatory in 2002. Two point-like radio sources were also detected in the central region.

According to the research team, the two black holes in NGC 6240 will eventually, in 10 million to 100 million years, spiral into each other and merge, producing a powerful burst of gravitational radiation.

Canalizo, who was in charge of planning and making the AO observations at the 10-meter Keck II Telescope, processed the near-infrared data for the team. De Vries made precise measurements of the positions of astronomical objects in the sky, allowing the researchers to match up their near-infrared images with the data at other wavelengths.

###

The University of California, Riverside is a doctoral research university, a living laboratory for groundbreaking exploration of issues critical to Inland Southern California, the state and communities around the world. Reflecting California's diverse culture, UCR's enrollment of about 17,000 is projected to grow to 21,000 students by 2010. The campus is proposing a medical school and already has reached the heart of the Coachella Valley by way of the UCR Palm Desert Graduate Center. With an annual statewide economic impact of nearly $1 billion, UCR is actively shaping the region's future. To learn more, visit www.ucr.edu or call (951) UCR-NEWS.

 

NGC 6240, 1 (of 2)

Caption: NGC 6240 is an ongoing collision of two gas-rich disk galaxies. Using adaptive optics at the Keck II Telescope, University of California researchers have resolved young star clusters formed because of the merger (small blue dots), and have identified which features within the twin nuclei are associated with the two supermassive black holes known to inhabit the nuclear regions. In this image taken in infrared light, the nucleus from each of the two galaxies is shown using a color scheme that emphasizes the detail within the nuclei. The green vertical line represents one second of arc, or 1600 light years at the distance of NGC 6240.

Credit: C. Max, G. Canalizo, and W. de Vries

NGC 6240, 2 (of 2)

Caption: An adaptive optics image of the double nucleus of the galaxy merger NGC 6240, taken in infrared light with the Keck II Telescope. The feature within the north nucleus labeled "North 2" is at the position of the northern supermassive black hole. The southern supermassive black hole is located just north (above) the feature labeled "South 1" in the south nucleus. The yellow vertical line represents one second of arc, or 490 parsecs at the distance of NGC 6240.

Credit: C. Max, G. Canalizo, and W. de Vries

 

 

 
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Chemical Compounds Boost Breast Cancer Risk

Pollutants, food ingredients, solvents may all cause harm, researchers say.

By Alan Mozes
HealthDay Reporter

MONDAY, May 14 (HealthDay News) -- A detailed analysis of hundreds of completed breast cancer studies has linked disease development with environmental exposure to more than 200 chemical compounds.

The finding is part of an effort to build a free, online breast cancer database for researchers and the public.

Described as "the most comprehensive of its kind," the database will highlight growing concern about environmental carcinogens such as pollutants, food contaminants, and organic solvents. The scope of the project will also extend to work that explores risk-related lifestyle factors such as diet, levels of physical activity, smoking/drinking habits and body mass.

"This compilation is a great effort, because it summarizes all the evidence and gives us hints of what to look for next," explained researcher Leslie Bernstein, a professor of preventive medicine with the Keck School of Medicine at the University of Southern California in Los Angeles.

The results are outlined in a supplement to the May 14th online issue of Cancer. The database is already accessible at either www.silentspring.org/sciencereview or www.komen.org/environment.

According to the American Cancer Society (ACS), carcinogens are defined as agents that instigate abnormal cell division or harmful changes in the structure of a cell's DNA. They include chemicals, radiation, or infectious agents, among other things.

The ACS also notes that with the exception of skin cancer, breast cancer is the most common cancer among American women. This year, almost 179,000 women in the United States will be diagnosed with the disease, and about 40,000 will die.

The International Agency of Research on Cancer has already classified 90 or so compounds as human carcinogens, according to the ACS. But Bernstein's team said that most of the chemicals to which people are routinely exposed have not undergone any testing for carcinogenic risk. An estimated 80,000 chemicals are registered in the United States for commercial use, according to the researchers.

For more than two years, Bernstein worked alongside colleagues from Harvard University, the Roswell Park Cancer Institute, and the Silent Spring Institute to amass and sort through approximately 900 national and international breast cancer studies focused on carcinogens.

The team honed in on 460 human breast cancer studies, of which more than 150 looked at specific environmental carcinogens among breast cancer patients. Most of those studies were conducted in the 1990s.

The remaining studies involved animal or laboratory research. The researchers pointed out that animal studies are valid references, because all known human carcinogens have also triggered tumors in animal subjects.

In the animal studies alone, evidence surfaced that linked 216 chemicals to the onset of breast tumors. These included 36 industrial chemicals, 6 chlorinated solvents, 18 products of combustion, 10 pesticides, 18 dyes, four type of radiation, 47 pharmaceuticals, and 17 hormones.

Of these compounds, the researchers isolated 73 that can be found in either human food or consumer products.

They noted, for example, the lingering hazards associated with polychlorinated biphenyls (or PCBs), which were typically used in the production of electrical equipment until federally banned in 1979. PCBs continue to pose a risk via contaminated rivers, fish, and pre-existing building construction, the researchers warned.

In addition, the authors categorized 35 compounds as carcinogenic air pollutants, including polycyclic aromatic hydrocarbons (or PAHs), which are byproducts of combustion.

The team also drew attention to another group of 25 organic compounds, including dioxins, which are produced by waste incineration and manufacturing. These carcinogenic chemicals are present in many American workplaces and place more than 5,000 women at an increased risk for breast cancer, the researchers said. These include women working in machine shops, dry cleaners, hairdressers, glass manufacturers, and aircraft maintenance facilities, all of which use harmful organic solvents.

Furthermore, among the identified carcinogens, 29 are produced in large amounts -- upwards of one million pounds or more per year.

The database project did not set strict guidelines as to how to limit exposure to carcinogens. But the authors said they encouraged research and government oversight into the problem. They advised that people do try and limit their exposure to PCB-contaminated fish, gasoline-generated air pollution, chlorinated tap water, non-stick coated cookware, and detergents containing fluorescent whiteners.

Just how carcinogenic, in terms of breast cancer risk, are these and other compounds on the list? The jury is still out on that question, Bernstein said.

"Women are terribly concerned about environmental causes of breast cancer," she said. "But it's really very difficult to study. Often the only way we've been able to look at some of these things is during occupational exposures or accidents -- what we usually call disasters."

"So, this work is a very useful tool for those of us who want to try to understand what we've missed in breast cancer. Now, it's up to us to do something with all this information," Bernstein said.

Janet Gray, a professor of psychology and the director of the program in science, technology and society at Vassar College in Poughkeepsie, N.Y., called the new database "an enormous contribution."

"Its greatest value is just the sheer comprehensive nature of the work, which allows both the public and researchers to have access to huge amounts of information in one place," she said. "I think this effort will really move us forward."

 

Known and Probable Carcinogens

Including Industrial Processes, Occupational Exposures, Infectious Agents, Chemicals, and Radiation)

What Is a Carcinogen?

Cancer is caused by abnormalities in a cell’s DNA (its genetic "blueprint"). These may be inherited from parents, or they may be caused by outside exposures to the body such as chemicals, radiation, or even infectious agents.

Substances that can cause changes that can lead to cancer are called carcinogens. Some carcinogens do not act on DNA directly, but lead to cancer in other ways, such as causing cells to divide at a faster rate, which could increase the chances that DNA changes will occur.

Carcinogens do not cause cancer in every case, all the time. Substances classified as carcinogens may have different levels of cancer-causing potential. Some may cause cancer only after prolonged, high levels of exposure. And for any particular person, the risk of developing cancer depends on many factors, including the length and intensity of exposure to the carcinogen and the person’s genetic makeup.

How Do We Determine if Something Is a Carcinogen?
Scientists get much of their data about whether something might cause cancer from laboratory (cell culture and animal) studies. Although it isn’t possible to predict with certainty which substances will cause cancer in humans based on animal studies alone, virtually all known human carcinogens that have been adequately tested produce cancer in lab animals. In many cases, carcinogens are first found to cause cancer in lab animals and are later found to cause cancer in people. Because there are far too many substances (natural and manmade) to test each one in lab animals, scientists use knowledge about chemical structure, other types of lab tests, and information about the extent of human exposure to select chemicals for testing.

Most studies of potential carcinogens expose the lab animals to doses that are higher than common human exposures. This is so that cancer risk can be detected in relatively small groups of animals. For most carcinogens, it is assumed that those that cause cancer at larger doses in animals will also cause cancer in people. Although it isn’t always possible to know the relationship between exposure dose and risk, it is reasonable for public health purposes to assume that lowering human exposure will reduce risk.

Another important way to identify carcinogens is through epidemiologic studies, which look at human populations to determine which factors might be linked to cancer. While these studies also provide useful information, they also have their limitations. Humans do not live in a controlled environment. People are exposed to numerous substances at any one time, including those they encounter at work, school, or home; in the food they eat; and the air they breathe. And it is usually many years (often decades) between exposure to a carcinogen and the development of cancer. Therefore, it can be very hard to single out any particular exposure as having a definite link to cancer.

By combining data from both types of studies, scientists are able to make an educated assessment of a substance’s cancer-causing ability. When the available evidence is compelling but not felt to be conclusive, the substance may be considered to be a probable carcinogen.

How Are Carcinogens Classified?

International Agency for Research on Cancer (IARC)

The most widely used system for classifying carcinogens comes from the IARC, which is part if the World Health Organization (WHO). In the past 30 years, the IARC has evaluated the cancer-causing potential of about 900 likely candidates, placing them into one of the following groups:

Perhaps not surprisingly, most of the agents are of probable, possible, or unknown risk. Only about 90 are classified as "carcinogenic to humans."

National Toxicology Program (NTP)

In the United States, the NTP releases the Report on Carcinogens about every 2 years. The NTP is formed from parts of several different government agencies, including the National Institutes of Health (NIH), the Centers for Disease Control and Prevention (CDC), and the Food and Drug Administration (FDA).

The Report on Carcinogens (RoC) identifies 2 groups of agents:

Unlike the IARC’s list, the RoC does not list substances that have been studied and found not to be carcinogens. Below are the lists of known and probable human carcinogens from both groups.

Known Human Carcinogens

International Agency for Research on Cancer (IARC)
"Carcinogenic to Humans" (Group 1)

Agents and Groups of Agents

Mixtures

Exposure Circumstances

National Toxicology Program (NTP) 11th Report on Carcinogens

"Known to Be Human Carcinogens"

Probable Carcinogens

International Agency for Research on Cancer (IARC)
"Probably Carcinogenic to Humans" (Group 2A)

Agents and Groups of Agents