Estrogen: Not just produced by ovaries -- ScienceDaily. A University of Wisconsin-Madison research team reports today that the brain can produce and release estrogen -- a discovery that may lead to a better understanding of hormonal changes observed from before birth throughout the entire aging process. The new research shows that the hypothalamus can directly control reproductive function in rhesus monkeys and very likely performs the same action in women. Scientists have known for about 80 years that the hypothalamus, a region in the brain, is involved in regulating the menstrual cycle and reproduction.
Within the past 40 years, they predicted the presence of neural estrogens, but they did not know whether the brain could actually make and release estrogen. Most estrogens, such as estradiol, a primary hormone that controls the menstrual cycle, are produced in the ovaries. Estradiol circulates throughout the body, including the brain and pituitary gland, and influences reproduction, body weight, and learning and memory. Why Do Chili Peppers Taste Hot? Science Graphic of the Week: See What’s Going on Inside the Eye of a Glowing Shark | Science. The density of photoreceptors (top) and ganglion nerve cells (bottom) in the retinas of bioluminescent lanternsharks.
Claes et. al/PLOS ONE Hundreds of feet underwater, where dim rays of sunlight mix with flickers from bioluminescent fish, lanternsharks rely on their sensitive eyes to survive. The image above shows how their retinas have adapted to life in the twilight zone. The eye of E. Spinax . Dr. The top row shows the density of photoreceptive rods in the retinas of three different species of lanternshark (red corresponds to more receptors). The bottom row shows the density of ganglion nerve cells, which aggregate the signals from the rods.
Each lanternshark has bright marks on its flanks, enabling its friends to recognize it and coordinate schooling and hunting. During the day, E. The three species also have something important in common: they use bioluminescence for camouflage. Sleeping In A Cool Environment May Boost Your Metabolism, And Here's Why. Scientists have long known that sleeping in a cool room can help you get a more peaceful snooze. But now new research suggests there's another big benefit -- it just may boost your metabolism. Researchers have found that cool temperatures can stimulate the growth of brown fat, a special kind of fat that burns energy, in your body -- which may boost your metabolic health and may protect against obesity and diabetes. "The big unknown until this study was whether or not we could actually manipulate brown fat to grow and shrink in a human being," study co-author Dr.
Paul Lee, an endocrinologist at the Garvan Institute of Medical Research in Sydney, Australia, said in a written statement. And the study suggests we can. For the four-month study, five healthy men were asked to live their lives normally during the day but spend their nights in a climate-controlled research lab in Bethesda, Maryland. What did the researchers find? “The cold month increased brown fat by around 30-40 percent," Dr. Peces bajo cero | General | Zoo Logik. Peces hay en todos los mares del Planeta, también en los que circundan los polos, en aguas cuyas temperaturas se encuentran por debajo de 0ºC. Parece imposible que así sea, porque cabría pensar que difícilmente pueden vivir peces en aguas que se encuentran a esas temperaturas, dado que sus líquidos internos podrían congelarse con facilidad. Las cosas, no obstante, no son tan sencillas cuando los líquidos en cuestión no son puros, sino disoluciones acuosas.
La concentración salina de los teleosteos marinos, -que son la gran mayoría de los peces de mar-, es tres veces más baja que la del agua de mar. Como es sabido, el agua destilada se congela a 0ºC, mientras que las disoluciones se congelan a temperaturas más bajas. De hecho, la temperatura de congelación de una disolución es dependiente de la concentración de sustancias disueltas; cuanto más alta es esa concentración, más bajo es el punto de fusión, esto es, menor es la temperatura a la que ese líquido se congela. Senses and Non-Sense: 7 Odd Hallucinations.
The many documented cases of strange delusions and neurological syndromes can offer a window into how bizarre the brain can be. It may seem that hallucinations are random images that appear to some individuals, or that delusions are thoughts that arise without purpose. However, in some cases, a specific brain pathway may create a particular image or delusion, and different people may experience the same hallucination.
In recent decades, with advances in brain science, researchers have started to unravel the causes of some of these conditions, while others have remained a mystery. Here is a look at seven odd hallucinations, which show that anything is possible when the brain takes a break from reality. 1. Alice-in-Wonderland syndrome This neurological syndrome is characterized by bizarre, distorted perceptions of time and space, similar to what Alice experienced in Lewis Carroll's "Alice's Adventures in Wonderland. " [7 Mind-Bending Facts About Dreams] 2. 3. 4. 5. 6. 7.
European acclaim for grade 9 experiment - dr.dk/Nyheder/Andre_sprog/English. 17. maj 2013 13.17 English Take 400 cress seeds and divide them into 12 trays. Then place the trays in two rooms at the same temperature, six in each room. Give the trays the same amount of water and sunlight over 12 days, but expose six of the trays to mobile phone radiation. This is the recipe for a biology experiment so ingenious that it has attracted international attention from leading biologists and radiation experts.
“We all thought we experienced concentration problems in school if we slept with our mobile phones at the bedside, and sometimes we also found it difficult sleeping,” explained Lea Nielsen, one of the five budding researchers. The experiment The school did not have the equipment to test the effect of mobile phone radiation on the girls themselves, which, as it turned out, was probably a good thing. The “healthy” cress, which was not exposed to radiation from the routers. Then the girls just had to wait 12 days, observe, measure, weigh and take photos. The reactions. Body Atlas Reveals Where We Feel Happiness and Shame.
Yellow shows regions of increased sensation while blue areas represent decreased feeling in these composite images. Image courtesy of Lauri Nummenmaa, Enrico Glerean, Riitta Hari, and Jari Hietanen. Chests puffing up with pride — and happiness felt head to toe — are sensations as real as they are universal. And now we can make an atlas of them. Researchers have long known that emotions are connected to a range of physiological changes, from nervous job candidates’ sweaty palms to the racing pulse that results from hearing a strange noise at night. But new research reveals that emotional states are universally associated with certain bodily sensations, regardless of individuals’ culture or language. Once More With Feeling More than 700 participants in Finland, Sweden and Taiwan participated in experiments aimed at mapping their bodily sensations in connection with specific emotions.
Hot-Headed The findings enhance researchers’ understanding of how we process emotions. Are These 10 Trendy Health Foods Worth The Hype? Urinating Standing versus Sitting: Position Is of Influence in Men with Prostate Enlargement. A Systematic Review and Meta-Analysis. Background It is suggested that the body posture during urination can influence urodynamic parameters in patients with Lower Urinary Tract Symptoms (LUTS) to an extent approaching pharmacological interventions. In this article, the influence of body position during micturition on maximum urinary flow rate (Qmax), voiding time (TQ) and post-void residual volume (PVR) in healthy males and patients with LUTS is analyzed by means of a systematic review and meta-analysis. Evidence Acquisition A systematic search was conducted in 14 medical databases. Results Eleven articles were included. Conclusion For healthy men, no difference is found in any of the urodynamic parameters.
Figures Citation: de Jong Y, Pinckaers JHFM, ten Brinck RM, Lycklama à Nijeholt AAB, Dekkers OM (2014) Urinating Standing versus Sitting: Position Is of Influence in Men with Prostate Enlargement. Editor: Robert S. Received: March 4, 2014; Accepted: June 5, 2014; Published: July 22, 2014 Copyright: © 2014 de Jong et al. Humans Capable Of Smelling 10 Odor Types, Study Suggests. From fruity to minty to popcorn-y, all smells can be classified as one of 10 types of aroma, scientists say. Taste, vision and hearing can be quantified, but a systematic description of smell has remained elusive.
Now, researchers have used mathematics to describe odors systematically and simplify them into 10 categories: fragrant, woody/resinous, fruity (non-citrus), chemical, minty/peppermint, sweet, popcorn, lemon, pungent and decayed. "It's an open question how many fundamental types of odor qualities there are," study researcher Jason Castro of Bates College said in a statement. "This is in striking contrast to olfaction's 'sister sense,' taste, where we know that five basic qualities seem to organize sensations," Castro said. [8 Strange Things Scientists Have Tasted] Castro and his colleagues took a standard database known as Andew Dravniek's 1985 Atlas of Odor Character Profiles.
The analysis resulted in 10 basic odor groups. To bloom or not to bloom? Researchers discover how flowering time is affected by temperature. Too early or too late blooming can have serious consequences for plants: It may reduce the seed harvest and jeopardize the reproductive success of an entire season. In order not to miss the optimal time of flowering, plants have therefore evolved an extensive control system that involves several dozen genes. Under the leadership of Markus Schmid, molecular geneticist at the Max Planck Institute for Developmental Biology in Tübingen, and in collaboration with the group of Richard Immink, of Wageningen UR (University & Research centre) in the Netherlands, an international team of researchers has studied two key genes that regulate flowering time in response to ambient temperature. According to their report in the current issue of Nature magazine online, they uncovered a clever molecular mechanism.
Many genes involved in the control of flowering time had already been known from previous studies on the plant Arabidopsis thaliana. Siberian hamsters show what helps make seasonal clocks tick. Many animals, including humans, have internal clocks and calendars to help them regulate behavior, physiological functions and biological processes. Although scientists have extensively studied the timekeeping mechanisms that inform daily functions (circadian rhythms), they know very little about the timekeeping mechanisms that inform seasonal functions. New research to be published this week in the online early edition of the Proceedings of the National Academy of Sciences shows, for the first time, that this measurement of seasonal time has an epigenetic component.
Epigenetics refers to an alteration in gene expression that occurs without a change in the sequence of DNA molecules. The research used Siberian hamsters, which only breed in the late spring and early summer, when days are the longest. It revealed the molecular mechanism behind how these hamsters avoid breeding in the fall and winter, thereby preventing births during the cold, resource-scarce winter months.
Your Sleep Quality Suffers Around the Full Moon - D-brief. The moon may be a harsh mistress, but she also might be to blame for your poor night’s sleep. A study in Current Biology shows for the first time that the moon’s shape can impact people’s sleep. Specifically, a full moon negatively affects sleep duration, deep sleep, how long it takes to fall asleep, and levels of melatonin (a sleep-related hormone). With a study like this, it’s important to make sure that nothing unduly influences the results, and the Swiss team responsible ensured this in two ways.
First, they made sure the subjects represented a wide range of people (they had 17 healthy young volunteers and 16 healthy older volunteers, with men and women in every group) and the laboratory conditions were carefully monitored and controlled for. Second, they didn’t bring in the whole “lunar” aspect of this sleep study until much later. Full moon woes It was a good thing they did.
In addition, sleep was less restful around the full moon. What the nose knows: Humans can sense 10 basic smells. For years, humans have had categories for colors, flavors and sounds, but when it comes to the sense of smell, things are a mess. Now, just as there are three primary colors and five basic tastes, researchers propose that odors can fall into 10 basic groups.
In the new scheme, woody smells like pine or fresh cut grass fall into one group. There are the sweet scents, like caramel, chocolate, vanilla. Florals and perfumes are one category, citrus fruits get another, and the rest of the fruit world is lumped into a third. Less pleasant odors like sour milk, gasoline and rotten meat have their own fetid designations. More complex aromas like baked bread or fresh-brewed coffee might be best described as a combination of two or more of these 10 elements, just "as a combination of pitches make up a chord," Jason Castro, associate professor of neuroscience and one of the authors of the new study published in the Sept. 18 issue of PLOS ONE, told NBC News. Some of that has to do with biology. New Brain Activity State Exists In 'Flat Line' Coma Patients, Scans Suggest. When a patient's brain falls completely silent, and electrical recordings devices show a flat line, reflecting a lack of brain activity, doctors consider the patient to have reached the deepest stage of a coma.
However, new findings suggest there can be a coma stage even deeper than this flat line — and that brain activity can ramp up again from this state. In the case of one patient in a drug-induced coma, and in subsequent experiments on cats, the researchers found that after deepening the coma by administering a higher dose of drugs, the silent brain started showing minimum but widespread neural activity across the brain, according to the study published today (Sept. 18) in the journal PLOS ONE. The findings were based on measures of the brain's electrical activity, detected by electroencephalography (EEG), which shows various waveforms.
In comatose patients, depending on the stage of their coma, the waveforms are altered. La adaptación de los tibetanos a la altura sigue siendo una incógnita | General | Zoo Logik. Las grandes posibilidades que ofrecen los métodos de análisis y de secuenciación de ADN han impulsado los estudios genéticos y han permitido trazar la historia de los grupos humanos con un alto grado de precisión. Durante los últimos años hemos asistido a un rosario impresionante de novedades relativas a la historia del linaje humano, tanto basadas en el registro fósil como en datos de ADN antiguo y actual. Además, también se han identificado zonas del genoma que han sido objeto de selección reciente, y se ha desbaratado la idea de que la especie humana dejó de evolucionar hace 50.000 años gracias a la tecnología. Al contrario, hay rasgos que se han seleccionado y extendido tras la expansión del neolítico, asociados al aprovechamiento de nuevos recursos alimenticios, y otros han experimentado también una intensa presión selectiva a cargo de otro tipo de factores, algunos seguramente de naturaleza cultural.
Como ya he señalado, los tibetanos toleran muy bien la hipoxia. Referencias: S. Los hongos alucinógenos provocan el patrón cerebral de los sueños. Scientists uncover new compounds that could affect circadian rhythm.