Tag Archives: human

Study Explains Skin’s Response to UVA Light

Researchers have strengthened their understanding of how skin cells called melanocytes sense ultraviolet light and act to protect themselves with melanin. In a new study, they report experiments showing that an ion channel well-known elsewhere in the body for its chemical sensitivity, plays a central role in this process.

PROVIDENCE, R.I. [Brown University] — Last year, a team of researchers at Brown University discovered that certain skin cells use a light-sensitive receptor found outside of the eye to sense ultraviolet light and quickly begin pumping out melanin to protect against DNA damage. In a new study, lab members identify a key player in that biomolecular chain of events that could someday become a pharmacological target for improving this protective response. (more…)

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Global Warming May Have Severe Consequences for Rare Haleakala Silverswords

HONOLULU — While the iconic Haleakalā silversword plant made a strong recovery from early 20th-century threats, it has now entered a period of substantial climate-related decline. New research published this week warns that global warming may have severe consequences for the silversword in its native habitat.

Known for its striking rosette, the silversword grows for 20-90 years before the single reproductive event at the end of its life, at which time it produces a large (up to six feet tall) inflorescence with as many as 600 flower heads. The plant was in jeopardy in the early 1900s due to animals eating the plants and visitors gathering them. With successful management, including legal protection and the physical exclusion of hoofed animals, the species made a strong recovery, but since the mid-1990s it has entered a period of substantial decline. A strong association of annual population growth rates with patterns of precipitation suggests the plants are undergoing increasingly frequent and lethal water stress. Local climate data confirm trends towards warmer and drier conditions on the mountain, which the researchers warn will create a bleak outlook for the threatened silverswords if climate trends continue. (more…)

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U of T Researchers Uncover Major Source of Evolutionary Differences among Species

TORONTO, ON – University of Toronto Faculty of Medicine researchers have uncovered a genetic basis for fundamental differences between humans and other vertebrates that could also help explain why humans are susceptible to diseases not found in other species.

Scientists have wondered why vertebrate species, which look and behave very differently from one another, nevertheless share very similar repertoires of genes. For example, despite obvious physical differences, humans and chimpanzees share a nearly identical set of genes. (more…)

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Harmful Protein-Coding Mutations in People arose Largely in the Past 5,000 to 10,000 Years

A study dating the age of more than 1 million single-letter variations in the human DNA code reveals that most of these mutations are of recent origin, evolutionarily speaking. These kinds of mutations change one nucleotide – an A, C, T or G – in the DNA sequence. Over 86 percent of the harmful protein-coding mutations of this type arose in humans just during the past 5,000 to 10,000 years.

Some of the remaining mutations of this nature may have no effect on people, and a few might be beneficial, according to the project researchers. While each specific mutation is rare, the findings suggest that the human population acquired an abundance of these single-nucleotide genetic variants in a relatively short time. (more…)

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Elevated Indoor Carbon Dioxide Impairs Decision-Making Performance

Berkeley Lab scientists surprised to find significant adverse effects of CO2 on human decision-making performance.

Overturning decades of conventional wisdom, researchers at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) have found that moderately high indoor concentrations of carbon dioxide (CO2) can significantly impair people’s decision-making performance. The results were unexpected and may have particular implications for schools and other spaces with high occupant density.

“In our field we have always had a dogma that CO2 itself, at the levels we find in buildings, is just not important and doesn’t have any direct impacts on people,” said Berkeley Lab scientist William Fisk, a co-author of the study, which was published in Environmental Health Perspectives online last month. “So these results, which were quite unambiguous, were surprising.” The study was conducted with researchers from State University of New York (SUNY) Upstate Medical University. (more…)

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Speaking of Ethics

Lecturer explores the imperatives of environmental ethics

Speaking to University of Delaware faculty and students and community members in Brown Lab on Monday night, Oct. 15, environmental philosopher Kathleen Dean Moore discussed how important it is for humans to realize their ethical responsibility to save the world from a climate crisis.

In a lecture titled “Why It’s Wrong to Wreck the World: Climate Change and the Moral Obligation to the Future,” Moore reflected on the relationship humans have with the environment and argued that once humans realize the impact of their actions, they will naturally feel a moral obligation to care for the planet. (more…)

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New Tool for CSI? Geographic Software Maps Distinctive Features inside Bones

COLUMBUS, Ohio – A common type of geographic mapping software offers a new way to study human remains.

In a recent issue of the American Journal of Physical Anthropology, researchers describe how they used commercially available mapping software to identify features inside a human foot bone – a new way to study human skeletal variation. (more…)

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What’s that Noise?

Paper describes new method to understand sources of noise in gene-expression

Abhyudai Singh, assistant professor of electrical and computer engineering at the University of Delaware, describes a new method to understand sources of “noise” in gene-expression that create variability in protein levels in a paper published in Molecular Systems Biology, a publication of Nature, on Aug. 28.

This noise is expressed as variability in the levels of proteins/mRNAs in a cell. (more…)

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