If you start smoking cigarettes, chances are you'll become addicted. But that's only part of the story, according to new research published in Psychopharmacology. After exposing rats to passive smoke and studying how their brains responded, the authors of the studies are suggesting that just being exposed to cigarette smoke may result in nicotine dependence.
In a set of four experiments on male Wistar rats, researchers investigated whether rats exposed passively to tobacco smoke would become dependent on nicotine. They specifically looked at how the rats' brains responded to being exposed to tobacco smoke and whether the rats displayed withdrawal symptoms.
Female fruit flies can be too attractive to the opposite sex –– too attractive for their own good –– say biologists at UC Santa Barbara. In a new PLoS Biology study, they report that too much male attention directed toward attractive females can lead to smaller families and, ultimately, a reduced rate of population-wide adaptive evolution.
The authors explain that the term "good looking," among fruit flies, refers to something, like a large body. From the perspective of a male fly, a desirable mate is a female that is larger and can therefore produce more offspring.
Not only is cardiovascular health good for children physically, it turns out that it may also promote intelligence. In a study published this week in PNAS, researchers say they have demonstrated a clear positive association between adolescent fitness and adult cognitive performance.
The results of the study also show the importance of getting healthier between the ages of 15 and 18 while the brain is still changing.
Despite the considerable amount of concern generated by the H1N1 outbreak earlier this year, the authors of a new study featured in PLoS Medicine believe it's impact will be relatively mild this flu season, with the number of hospitalizations and deaths related to the virus likely to remain much lower than anticipated.
"As more detailed data have become available, we have been able to improve our estimates of how severe this disease is. Early on, it was difficult to measure the flu's impact and it was crucial to plan for the full range of possible outcomes. Fortunately, the virus now appears to be near the milder end," said Marc Lipsitch, professor of epidemiology at HSPH and the study's senior author.
Astronomers at the Max Planck Institute for Astronomy have discovered and directly imaged a faint celestial body that orbits the star GJ 758. Its mass is estimated to be between 10 and 40 Jupiter masses.
Accordingly, it is either a giant planet or a brown dwarf, a would-be sun. One thing is certain: with a temperature of around 330 degrees Celsius, GJ 758 B is the coldest companion of a Sun-like star ever to be directly imaged. The discovery is detailed in Astrophysical Journal Letters
Social isolation and stress are two environmental mechanisms likely to contribute to breast cancer susceptibility, researchers from the University of Chicago said this week.
Their study, published in PNAS, found that isolation led to higher production of a stress hormone, corticosterone, among rats that were kept alone and subjected to the disturbances of colony life as well as stressful situations, such as the smell of a predator or being briefly constrained. Additionally, the isolated rats took longer to recover from a stressful situation than rats that lived together in small groups.