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U.S. researchers have found that Zika can attack special populations of brain cells in adult mice in the part of the brain involved in learning and memory, raising new questions about how the virus may be impacting millions of adults who have been infected with the virus. The findings, published on Thursday in the journal "Cell Stem Cell," are the first to look at whether Zika can attack the same kinds of cells in adult mice that they do in fetal mice.

Massive vines that blanket the southern United States, climbing high as they uproot trees and swallow buildings. A ravenous snake that is capable of devouring an alligator. Rabbit populations that eat themselves into starvation. These aren't horror movie concepts - they're real stories. But how could such situations exist in nature? Jennifer Klos gives the facts on invasive species.

Curriculum materials for the following topics: HeLa Cells & HPV Genes: Immortality & Cancer, which reviews basic cell biology, tissue culture, and human subjects research in the context of privacy, rights, and compensation. Link: http://www.stemcellcurriculum.org/hela-cells-hpv-genes-immortality-cancer.html · Eggs & Blood: Gifts & Commodities, which addresses the value placed on some bodily tissues/cells and not on others. Link: http://www.stemcellcurriculum.org/eggs-and-blood.html · Disease, Disability, & Immortality: Hope & Hype, which explores the natural physical and cognitive variability in the human population and questions the goal of a "cure" in biomedical research. Link: http://www.stemcellcurriculum.org/disease-disability-immortality-hope-hype.html · Stem Cells & Policy: Values & Religion, which analyzes how policy is shaped in pluralistic societies that require tolerance of different points of view. Link: http://www.stemcellcurriculum.org/stem-cells-policy-values-and-religion.html

Deadly bacteria are spreading through the oceans as waters warm up, and are increasing infection risks, according to a new study. Multiple species of rod-shaped Vibrio bacteria live in the world's oceans, and their populations rise and fall based on many different variables, changing the likelihood of making people sick.

The Ebola epidemic that tore through West Africa in 2014 claimed 11,310 lives, far more than any previous outbreak. A combination of factors contributed to its savagery, among them a mobile population, crumbling public health systems, official neglect and hazardous burial practices. But new research suggests another impetus: The virus may have evolved a new weapon against its human hosts. In studies published on Thursday in the journal Cell, two teams of scientists report that a genetic mutation may have made Ebola more deadly by improving the virus's ability to enter human cells.

This case study focuses on the relationship between evolution and plasticity using a hands-on, inquiry-based approach. Students view examples from the literature that illustrate the difference between nature and nurture, or the relative contributions of genes and the environment in shaping phenotypes. Using the Trinidadian guppy system as an example, students learn about seminal work in the field in addition to exploring quantitative genetic techniques used to partition phenotypic variance between genes (G) and the environment (E). They use real data from one of the publications cited in the case to graph reaction norms illustrating GxE interactions at the family and population level. The inquiry-based approach means that students are introduced to new concepts in a stepwise fashion, and asked to develop and build their understanding using causal, explanatory evidence. The case concludes with an exercise in which students apply their knowledge to a real conservation problem in Trinidad and Tobago, where guppies are native. This case would be appropriate for an upper level biology, genetics, or evolution course.

This case study explores the controversy surrounding Yellowstone bison (Bison bison) and the relationship between wildlife management and pluralist democracy. In the late 1960s Yellowstone National Park suspended the policy of strictly managing bison by culling in favor of "natural processes" management. This led to dramatic herd growth and to bison exiting the park in winter in search of forage. Montana cattle ranchers reacted angrily for fear that the animals would infect their cattle with brucellosis. Since 2000, several government agencies have administered the Interagency Bison Management Plan, which uses culling to manage the population at around 3,000 head. The resumption of culling has upset environmental groups, while the recently approved expansion of bison habitat beyond park boundaries continues to upset ranchers.  The ongoing political battle between ranchers, environmentalists, Native American tribes and government agencies shows how difficult it can be to balance legislative mandates, ecological values, and conflicting public demands. The case study may be employed in a variety of courses, including American Government, Public Policy, Interest Groups, Environmental Studies and National Parks.

This case study is based on the 2014 Ebola epidemic that spread to multiple highly populated countries in West Africa, making it the largest and most devastating outbreak in the history of the virus. The storyline, inspired by a compilation of factual information, unfolds through a fictional narrative wherein students play the role of an infectious disease specialist in training to learn about the techniques used in the detection, diagnosis, and management of Ebola virus outbreaks. The story is presented as an interrupted "clicker case" that combines problem-based case teaching methods with simulated biological laboratory inquiry through the use of Case It, a free molecular biology software, along with the NCBI's online bioinformatics tools and databases. Students work in groups to collaboratively explore various biological and social aspects of this infectious disease outbreak. This case was developed for senior students at the secondary level and can be modified for use in an introductory biology, microbiology, or epidemiology course at the undergraduate level.

Penn State University anthropologist Dr. Nina Jablonski walks us through the evidence that the different shades of skin color among human populations arose as adaptations to the intensity of ultraviolet radiation in different parts of the world.

Researchers analysed the genomes of 51 individuals who lived between 45,000 years ago and 7,000 years ago. The results reveal details about the biology of these early inhabitants, such as skin and eye colour, and how different populations were related. It also shows that Neanderthal ancestry in Europeans has been shrinking over time, perhaps due to natural selection. The study in Nature journal shines a torchlight over some 40,000 years of prehistory, showing that ancient patterns of migration were just as complex as those in more recent times.

To address this issue, we have developed case studies that track the evolution of traits from their origination in DNA mutation, to the production of different proteins, to the fixation of alternate macroscopic phenotypes in reproductively isolated populations.

Why is the North American population of monarch butterflies declining? In 1999, a study published in the journal Nature suggested that a variety of genetically modified corn was killing these iconic butterflies. While it was later shown that the conditions in this study did not mirror those in the field, the results garnered a lot of media attention and many people today still believe that monarchs are being killed by GMOs. This case familiarizes students with the plight of the monarchs, encourages them to think about how to test the hypothesis that a toxin is responsible for their decline, and takes a critical look at several studies that investigated the role of Bt corn in the life cycle of monarchs. This interrupted case takes 60-90 min to complete, requires little to no science background, and can be used to explore the ecology and wildlife management of monarchs; risk assessment, toxicity, and exposure; experimental design, the scientific method, hypothesis, and critical thinking; or the relationship between science, the media and the public.

2:25 video  Scientists have recently discovered that the limbs of some sea stars have been turning into goo, and populations are dying off! Why is this happening, and will this hurt their ecosystem? Join Laci as discusses how this disease is spreading, and why it have some negative consequences.

Scientists and clinicians have demonstrated that a neuroprotectant drug protects the human brain against the damaging effects of stroke. In patients who had ruptured brain aneurysm, which comprise a population of patients at very high risk of neurological damage, those treated with Tat-NR2B9c all had good neurological outcomes, whereas only 68% of those treated with placebo had good outcomes.

The 1000 Genomes Project is an international collaboration to produce an extensive public catalog of human genetic variation, including SNPs and structural variants, and their haplotype contexts. This resource will support genome-wide association studies and other medical research studies. The genomes of about 2500 unidentified people from about 25 populations around the world will be sequenced using next-generation sequencing technologies. The results of the study will be freely and publicly accessible to researchers worldwide. Further information about the project is available in the About tab. Information about downloading, browsing or using the 1000 Genomes data is available in the Data tab.

This explains the techniques and the virtual simulation allows interactive practive

comprehensive data repository and analysis tools with many data sources to graph and investigate

Genetic differences among ethnically diverse individuals are largely due to structural elements called copy number variants (CNVs), according to a study published today (August 6) in Science. Compared with other genomic features, such as single nucleotide variants (SNVs), CNVs have not previously been studied in as much detail because they are more difficult to sequence. Covering 125 distinct human populations around the world, geneticist Evan Eichler at the University of Washington in Seattle and an international team of colleagues studied the genomes of 236 people-analyzing both SNVs and CNVs. "The take-home message is that we continue to find a lot more genetic variation between humans than we appreciated previously," Eichler told The Scientist.

5:27 video, Our planet was once populated by megafauna, big top-of-the-food-chain predators that played their part in balancing our ecosystems. When those megafauna disappear, the result is a "trophic cascade," where every part of the ecosystem reacts to the loss. How can we stay in balance? George Monbiot suggests rewilding: putting wolves, lions and other predators back on top -- with surprising results.

In the past decade, the US honeybee population has been decreasing at an alarming and unprecedented rate. While this is obviously bad news for honeypots everywhere, bees also help feed us in a bigger way -- by pollinating our nation's crops. Emma Bryce investigates potential causes for this widespread colony collapse disorder.