Sunday, October 27, 2013

Beauty Sleep isn’t just for Princesses


Picture provided by Science News. Depicts colored tracers penetrate more deeply into a mouse’s brain when it’s asleep (left, red tracer) than awake (right, green tracer).

Sleep has always been a significant biological process that has intrigued people from ancient to modern times. Ancient cultures held different views on sleep depending on their nomadic or sedentary lifestyle and survival needs. Sleep is an important part of our circadian rhythm and holds natural rejuvenating qualities. Many of the benefits of sleep are being revealed with the aid of new technologies. Dr. Maiken Nedergaard, from the University of Rochester Medical Center, is a pioneer in the scientific community. Her research team recently conducted a study to determine if during sleep the brain cleanses itself by flushing out unwanted toxins that accumulate during active hours. In order to study this, the research team injected dye into mice’s cerebrospinal fluid, which is the clear liquid that surrounds the brain and spinal cord, to observe the travel route of the dye through the brain. The data showed that the dye flowed when the mice were asleep or unconscious and remained stagnant when the mice were awake. This helped support their hypothesis because the cell structure must have shifted during sleep creating space between the brain cells, which allowed the dye to be flushed out. The increase in space between the brain cells is most likely controlled by the glymphatic system, which regulates the flow of cerebrospinal fluid in the brain. To further investigate the increased space between the brain cells, the researchers tested it with electrodes. They inserted the electrodes into both alert and unconscious mice’s brain and measured the distance.  The scientists compared the results and the space increased by 60% in sleeping mice. Additional support of this is that the glia cells control the shrinking and swelling of the glymphatic system. When noradrenaline, an arousal hormone responsible for increasing the control cell volume, is blocked it induces asleep or unconsciousness and increases fluid flow and brain cell spacing. Lastly, researchers conducted a test to see if there is a connection between the glymphatic system and neurodegenerative disorders. They injected beta-amyloid, which is a protein associated with Alzheimer’s disease, into the brain to measure how long it remained in the brain when asleep or awake. Scientists observed that the beta-amyloid was flushed out quicker when the mice were asleep. This outcome supports that the brain normally clears out toxic molecules from the brain. The glymphatic system could be the new target for treating disorders and be a major breakthrough in the medical field. There are many aspects and complex workings of the brain we have not discovered yet but we are slowly gaining more understanding of the biological processes.


Saey, Tina Hesman. Sleep allows brain to wash out junk. Science News. Science News Magazine of the Society for Science and the Public, 17 Oct. 2013. Web. 23 Oct. 2013.

Sunday, October 20, 2013

Humpback Whales are Rock and Rollin' on the Seafloor




Picture from FreeDigitalPhotos.net


Picture from FreeDigitalPhotos.net



Humpback whales are one of the most admired ocean mammals due to their tremendous size and grace.  They are known for their surface feeding including acrobatic jumps, which has helped spark the success of the whale watching industry. Humpbacks are known for capturing fish in their large mouths by creating bubble nets with the assistance of other whales in the pod. Humpbacks utilize the lunge feeding method for retrieving prey, primarily herring and sand lance, which entails the whales speeding through large numbers of fish condensed into a “bait ball” with their mouths open. Once inside the humpback’s mouth, baleen plates separate the fish from the water, which is then squirted out of the blowhole, while the fish are passed through the whale’s throat to the stomach. For years scientists believed this was their main technique of acquiring food but the humpbacks that inhabit the Gulf of Maine are proving them wrong. The Stellwagen Bank National Marine Sanctuary and the Great South Channel monitor the local humpbacks using tags and critter cams to track their location and migration patterns. After the data is collected the results are three dimensionally mapped for a visual representation. Recently new data surprised scientists and sparked an entirely new investigation of the humpback whales. The maps showed humpbacks swimming to uncommon depths between 11:00 p.m. and 4:00 a.m. The scientists relied on the critter cams for answers. It showed that the whales were engaging in “bottom side rolls” because the whale’s rostrum, a snot-like projection, hit the seafloor and the whale’s ventral pleats expanded indicating feeding. The scientists theorized that the humpbacks somehow acquired this new skill of shaking up the sand to expose the hidden sand lance, which normally gather around the seafloor at night. The whales perform the bottom side rolls at a rate of 30 rolls per hour at about 1-2 meters above the sea floor. Furthermore, the whales execute the bottom side roll as a group to uncover a larger portion of the sand lance. They speculate that the whales must have a previous family or close bond to have learned this behavior . The same family relationships are viewed during surface feeding when the bubble net is implemented. Humpback whales are a family oriented species that communicate new feeding and survival skills to each other. The scientists investigated other Gulf of Maine humpbacks that focused on herring as a main food source and this behavior was not witnessed.  This discovery will open new doors for understanding the behaviors of the humpback whales and fuel continued research. The only concern with this observed behavior is the risk of the whales becoming entangled in seafloor fishing gear such as, gillnets and trap fisheries. More research needs to be conducted to determine exactly why the humpbacks have resorted to this behavior. A possibility is that the food source at the surface is not as plentiful or the whales are not as successful in capturing prey due to anthropogenic causes. 




National Oceanic & Atmospheric Administration. “Research reveals   bottom feeding techniques of tagged humpback whales in   Stellwagen Bank National Marine Sanctuary.” NOAA: National   Marine Sanctuaries, 26 Sept. 2013. Web. 18 Oct. 2013.
Zieliniski, Sarah. “The bottom feeding behavior of humpback   whales.” Science News: Magazine of the Society for   Science &   The Public, 8 Oct. 2013. Web. 18 Oct. 2013.

Sunday, October 13, 2013

Building Blocks Literally Made Out of Rock

Picture Provided by FreeDigitalPhotos.net


Scientists recently discovered the components of water circulating within the rubble of a star. The GD 61 white dwarf star shattered an asteroid due to its gravitational pull, exposing the asteroid’s contents. A white dwarf star is classified as a dying star that has a strong pull, which draws in neighboring asteroids and planets. GD 61 is 150 light-years away from the constellation Perseus. Perseus, named after a Greek mythological figure, is found in the northern sky and is 250 million light-years away from Earth. Even though the distance away from Earth is so extensive, the Hubble Space Telescope was able to identify the contents of the asteroid rubble. They were determined to be iron, magnesium, and oxygen. The presence of oxygen shocked scientists and led them to only one conclusion. Water had to be present at one point in time for oxygen to be found in the asteroid. Oxygen is vital for the basis of life and its development. Oxygen is one of the main elements found in water, H2O, and it allows for organisms to flourish in aerobic conditions. On Earth the accumulation of oxygen in the atmosphere allowed terrestrial organisms to sustain through respiration. Oxygen is the explanation as to why organism evolved, developed, and reached their success today. The discovery of oxygen in the asteroid is very crucial in understanding the beginning and evolution of life. Finding oxygen ultimately leads to water, which is metaphorically the match that can spark life on a planet. The possibility of life in other areas of the universe is exhilarating and evidence such as this fuels continued research. Scientists believe the amount of water stored in these rocks could have filled massive bodies of water, creating speculation that a planet similar to Earth once orbited GD 61. It is difficult to prove completely if this is the reason there is water in the asteroid, but it is a theory that provides hope and inspiration to the scientific community.

J. Farihi, B.T. Gänsicke and D. Koester. Evidence for water in the rocky debris of a disrupted extrasolar minor planet. Science. Vol. 342, October 11, 2013, p. 218. doi: 10.1126/science.1239447.