Keck Observatory announces upcoming astronomy talk
Keck’s next virtual Public Astronomy Talk will be held at 5 p.m. Nov. 18 and will feature Elizabeth Tasker, associate professor, Japan Aerospace Exploration Agency (JAXA), Institute of Space and Astronautical Sciences (ISAS), presenting “A planet not our own.”
We thought we understood the planets of our solar system until we discovered new worlds beyond our own Sun – planets the size of Jupiter with orbits completed in an Earth day, planets with two suns in the sky, and others with seas of tar or endless oceans. How did these worlds form, how did we find them, and could any of these discoveries be at all like our own Earth? Join us as Tasker helps us get acquainted with this fascinating field of science.
The talk will be streamed online at https://keckobservatory.zoom.us/j/98010004710 with meeting ID 980 1000 4710. The talk will also be live-streamed on Facebook.
How do fish tolerate changes in salinity?
Fish that live in both seawater and freshwater must adjust to changes in salinity in order to survive. But how do they recognize the salt concentration in their immediate environment?
A new multinational study, led by assistant research professor Andre Seale of the University of Hawaii at Manoa College of Tropical Agriculture and Human Resources Department of Human Nutrition, Food and Animal Sciences, is expanding knowledge of how specialized cells can sense the environment, respond to environmental change and regulate the internal environment.
The research is based on the notion that growth and environmental adaptation are regulated through the orderly release of hormones by the neuroendocrine system, which integrates information from genes and the environment.
“We knew from previous work using Mozambique tilapia, a fish widely used in aquaculture, that the hormone prolactin is responsible for maintaining salt-and-water balance,” said Seale. “So we used bioinformatics to identify the genes that are both sensitive to environmental salinity and regulate the expression of prolactin.”
The next step is to identify DNA targets in the gene that respond to salinity challenges, and from there, develop biomarkers to identify salinity stress and adaptation in aquaculture and wild fish, including how salinity may affect their health and growth.
“Other vertebrate genomes could be searched for conserved DNA sequences, which might potentially unveil new targets that, in turn, would shed light on how the body responds to changes in salt concentration and potentially unveil novel markers for salinity stress,” Seale added.
The study, “Transcriptional regulation of prolactin in a euryhaline teleost: Characterisation of gene promoters through in silico and transcriptome analyses,” appears in the latest Journal of Neuroendocrinology.
Living in noisy neighborhoods may raise your dementia risk
Long-term exposure to noise may be linked to an increased risk for Alzheimer’s disease and other forms of dementia.
Researchers did periodic interviews with 5,227 people 65 and older participating in a study on aging. They assessed them with standard tests of orientation, memory and language, and tracked average daytime noise levels in their neighborhoods for the five years preceding the cognitive assessments. About 11% had Alzheimer’s disease, and 30% had mild cognitive impairment, which often progresses to full-blown dementia.
Residential noise levels varied widely, from 51 to 78 decibels, or from the level of a relatively quiet suburban neighborhood to that of an urban setting near a busy highway. The study is in Alzheimer’s &Dementia.
After controlling for education, race, smoking, alcohol consumption, neighborhood air pollution levels and other factors, they found that each 10 decibel increase in community noise level was associated with a 36% higher likelihood of mild cognitive impairment and a 29% increased risk for Alzheimer’s disease. The associations were strongest in poorer neighborhoods, which also had higher noise levels.
The reasons for the connection are unknown, but the lead author, Jennifer Weuve, an associate professor of epidemiology at Boston University, suggested that excessive noise can cause sleep deprivation, hearing loss, increased heart rate, constriction of the blood vessels and elevated blood pressure, all of which are associated with an increased risk for dementia.