How Selective Hearing Works in the Brain

Selective hearing is an involuntary tendency to focus on an individual speaker in any environment. Humans who have selective hearing are able to ignore all that is occurring around them. What makes people with selective hearing different from people who just decide to tune out the rest of their environment is that people with selective hearing do not realize or choose when to tune out the environment. The article, “How Selective Hearing Works in the Brain,” tells how UCSF neurosurgeon Edward Chang, MD, a faculty member in the UCSF Department of Neurological Surgery and the Keck Center for Integrative Neuroscience, and UCSF postdoctoral fellow Nima Mesgarani, PhD, worked with three patients that went through a brain surgery for their severe epilepsy. The UCSF team performed an experiment on the patients. The patients had to listen to two speech samples (that played at the same time) where different phrases were spoken by different people. After, the patients had to identify words that they heard were spoken by one of the two speakers. In the end, the UCSF team found that neural responses in the auditory cortex (the part of the brain that deals with hearing information) only reflected those of the targeted speaker. Edward Chang stated, “The algorithm worked so well that we could predict not only the correct responses, but also even when they paid attention to the wrong word.” This experiment opens the door toward conducting more research and focusing on ways of examining disorders like attention deficit disorder.

            When was the last time you completely ignored what someone was saying to you, and not even notice that the individual was talking to you? Well, that would be selective hearing. People use selective hearing throughout their lives to focus on something that they want to hear. Selective hearing occurs involuntarily throughout some humans. Unfortunately, selective hearing does not have a cure. However, selective hearing it is not harmful (it will just make the person speaking to you mad).  

            This article was very educational, and interesting. Before reading this article, I did not understand the scientific explanation of how selective hearing works in the brain (but know I do). However, the article should have talked about the percentage of human population that suffers with selective hearing.

"How Selective Hearing Works in the Brain." Biology News Net. 18 Apr. 2012. Web. 26 Apr. 2012. http://www.biologynews.net/archives/2012/04/18/how_selective_hearing_works_in_the_brain.html. 

http://www.biologynews.net/archives/2012/04/18/how_selective_hearing_works_in_the_brain.html

Dow Corn, Resistant to a Weed Killer, Runs Into Opposition

                 To those who do not know 2,4-D is a powerful herbicide and was used in the notorious Agent Orange defoliant which was used in the Vietnam war to expose vietnam guerrilla fighters. Years later it was discovered that Agent Orange lead to birth defects, cancer, and other health problems. Now 2,4-D is being used as a weed killer on corn that has been genetically mutated by the company DOW, to not be damaged by this herbicide by making a protein that is able to break down 2,4-D so that the chemical is not harmful to the plant. DOW and its allies have said that linking the 2,4-D chemical to the harmful medical side effects of Agent Orange because the harm done by Agent Orange was actually from a different ingredient (2,4,5-T) which has been of the market for many years. There is still argument today weather or not 2,4-D should be considered a human carcinogen. The dept. of Agriculture in D.C. has started leaning toward the approval of this genetically mutated corn and many farmers believe that there is an almost urgent need for this kind of corn like Mr. Hurst a farmer in Missouri who says "I think it's a crisis , and we need something to have a solution to get rid of resistant weeds". This corn is also not the only on of its kind Dow is working on soybeans and cotton also immune to 2,4-D along with other agricultural giants like Monsanto. The history of using genetically mutated plants that are immune to certain pesticides has been a success but not all good. Monsanto created a soybean that had been mutated to not be damaged by the chemical glyphosate commonly known as Roundup was so successful that about 90% of the soybeans grown in the states were from this genetically altered plant. Now years after farmers have used roundup so much that the weeds have also developed an immunity to the chemical and farmers are forced to weed their whole fields by hand. There is also the issue of the 2,4-D chemical drifting from one farm with plants immune to the chemical to another farm where the plants are still susceptible. The chemical can also vaporize and travel for miles in the air. DOW says that they are working on now formulations of 2,4-D that is far less prone to vaporization. DOW will also force those who purchase its genetically altered corn to also buy their new pesticide. 

We should pay close attention to this article for now in our modern time we are seeing more and more foods altered in labs to be more efficient for the companies and in a way making agriculture more like a factory with the exact same product every time. This article is also important because this is a growing ethical issue for the planet if it is wise to manipulate nature in a way for our own good and that we don't become too reliant on these mutated plants. This article is greatly important to our Biology class because we have just recently been learning about genetic mutation in plants and the pros and cons about them and I think it really relates to what we have been studying showing that what we learn in class can be directly relate to the real world.

This article was a pretty easy read it was a little long but very interesting on the whole. I really enjoyed this article and the knowledge I gained from reading it. I think it was very interesting how we were just taking about genetic mutation in class. I would say anyone interested in this subject should read this article        


"http://www.nytimes.com/2012/04/26/business/energy-environment/dow-weed-killer-runs-into-opposition.html?pagewanted=2&_r=1&ref=science"http://www.nytimes.com/2012/04/26/business/energy-environment/dow-weed-killer-runs-into-opposition.html?pagewanted=2&_r=1&ref=science 

Mysterious Comsic Rays Leave Scientists in the Dark

Imagine a burst of energy 100 million times greater than the greatest man made burst of energy ever created.  Charles Choi wrote the article, “Mysterious cosmic rays leave scientists in the dark,” that talks about how scientists have recently gained new evidence of this burst of energy named a, “Cosmic Ray.” A cosmic ray is a streak of subatomic particles across deep outer space.  University of Wisconsin professor and leader of the “IceCube” observatory preached how nature is very capable of doing this.  He followed by explaining, “There are basically only two ideas on how she does this — in gravitationally driven particle flows near the supermassive black holes at the centers of active galaxies, and in the collapse of stars to a black hole, seen by astronomers as gamma-ray bursts.”  More studies suggest that this ray can emit as much energy as the sun over its entire lifetime in a couple of minutes or even in a couple of seconds.  In the past scientists have believed that the cause of this rare event was due to gamma ray bursts but new evidence suggests that this is not the case.  The IceCube observatory has been the leading researcher on this topic over the past few years.  They created special detectors that can detect sub atomic particles passing through it in order to obtain neutrino astronomy data.  With this data they recently partially ruled out gamma rays as instigators of these cosmic rays.

            This recent news really connects to our lives as human beings.  This new evidence of cosmic rays enhances the gap in knowledge of what’s going to happen in our future.  I don’t know if it’s just me but I don’t really think these rays bode well for our planet.  The information and research that we have gathered on cosmic rays seems very nebulous to me.  What if these large bursts push our planet or another planet off their course.  If that were to happen then there could be collisions and that’s certainly not what we want to happen in the future.

            I thought that this article was very well written.  Choi made it easy to understand through his tone and word choice.  I really liked how he chose quotes that really fit the article.  The quotes went along with his argument smoothly.  Also I liked how he broke the article into sections.  This allowed for better understanding and allowed for me to keep up with the story.   One thing that I thought Choi could have done better was that he could have provided more research about past studies of cosmic rays.  Overall, I thought this was a very good article and a great read.  I recommend this article to anyone with a curious mind.

Choi, Charles Q. "Mysterious Cosmic Rays Leave Scientists in the Dark." Msnbc.com. Msnbc Digital Network, 18 Apr. 2012. Web. 18 Apr. 2012. <http://www.msnbc.msn.com/id/47089794/ns/technology_and_science-space/>.

http://www.msnbc.msn.com/id/47089794/ns/technology_and_science-space/#.T49gTBxBRfA

The Power of a Radically Affordable Irrigation Pump

I read the article “The Power of a Radically Affordable Irrigation Pump”, posted onto the National Geographic website by Sandra Postel. This article gave insight into the use of the recently invented treadle pump. This pump is based for agricultural families in Southeast Asia and Sub-Saharan Africa. These families are in poverty and are hungry because they don’t have the technology or the resources to make enough crops during the dry season. The treadle pump, invented by Norwegian engineer Gunnar Barnes, is extremely helpful to farmers as, “The operator pedals up and down on two poles (called treadles), which activates a cylinder that suctions water up through a shallow well. The water then empties into an irrigation ditch and travels down the field to irrigate small plots of rice and vegetables.” The great thing about this pump is that it will only cost these families $35. Farmers can irrigate up to half an acre worth of crops with this simple device. The families can produce more crops to escape hunger, and as they make higher value crops, they can escape poverty as well. Eighty-four manufacturers make treadle pumps in Bangladesh and over 1.4 million pumps have been sold since 1984.  Now the International Development Enterprise has set up local posts to sell more pumps to Bangladeshi families in need. Along with the IDE, a non-profit company called KickStart has been giving variations of the treadle pump to farmers in Sub-Saharan Africa. This new affordable pump is changing lives and helping troubled families escape poverty and hunger.

                At this point in history over 850 million people are hungry in the world. Most of them cannot feed themselves or their families because they do not have the resources or the technology to produce enough food. Troubled farmers in Africa and Asia cannot produce enough crops during the difficult dry season, but thanks to the treadle pump, the families can irrigate their fields and have enough food to support their family and sell higher priced crops to the market. Hunger is such a big problem in our world today and so many organizations have been working towards helping people, and the treadle pump is helping the cause to giving everyone food. Each treadle pump sold gets us even closer to our goal of making sure that no one goes hungry.

                Reading the article “The Power of a Radically Affordable Irrigation Pump”, posted by Sandra Postel, really made me happy because I love reading stories about new inventions that help troubled people. Farming life in Sub-Saharan Africa and Southeast Asia is extremely tough, and many farmers have troubles during the hard dry season, but Gunnar Barnes creates a simple way to irrigate their fields. This article is well-written and describes the overview of the treadle pump really well. I really enjoyed this article and I hope my classmates enjoy it as well.

http://newswatch.nationalgeographic.com/2012/04/18/the-power-of-a-radically-affordable-irrigation-pump/

posted for J. Flannery

Melting Glaciers Liberate Ancient Microbes

     The article “Melting Glaciers Liberate Ancient Microbes” describes how global warming and the melting polar ice sheets will release microbes and bacteria from 750,000 years ago into the environment. In the past, the ice sheets appeared to not be able to support life by scientists but have recently been found out to contain an amount of microbe cells that is 1000 times the population of humans on earth. This discovery shows that the ice allows these microbes to store their genes so certain things that were extinct can come back. One concern of the scientists is that as the cells come out of the glaciers they could just turn into compost that generates Methane and Carbon dioxide as they decay which could lead to more greenhouse gas emissions. All of these microorganisms being put into the ocean could mess with the oceans chemistry. The researchers still do not understand how an organism can “sit for 750,00 years in some state of suspended animation”. Scott Rogers, a biologist and professor at Bowling Green University found a living 140,000-year-old plant virus in ice from Greenland. He believes that certain viruses could come back and possibly affect humans, but it would be unlikely for human viruses to be able to survive in the harsh ice conditions.

            I think this article was very interesting because I had no idea anything could survive in ice for hundreds of thousands of years. I don’t know how that would be possible because those cells would have almost no source of nutrients or water while the glacier is very cold and frozen.

            I think this is relevant to today because it shows how our emissions are affecting the world and it presents a new possible problem with the fact that these microbes could become a new source of emissions in the future if the ice continues to melt.

 > http://www.scientificamerican.com/article.cfm?id=melting-glaciers-liberate-ancient-microbes&page=3

posted for C. Gordon

Emperor Penguins Counted From Space -- A First

In the National Geographic article, “Emperor Penguins Counted From Space – A First”, scientists are astounded of what a new piece of technology can do.  Thanks to a futuristic piece of technologic engineering, a satellite is now capable of capturing high-resolution photographs from space. However, these are not regular photographs. This is a new technique called pan sharpening, which captures such high-resolution photos that scientists can tell the difference between penguin poop and ice chunks on the ground. In the article, one of the studies co-authors Michelle LaRue said it’s the same thing as “when you’re looking through binoculars and tightening them up, making [your subject appear in] finer detail.” This technique of extremely high quality photo capturing from space satellites has a variety of essential and immensely important uses that scientists can utilize.  For example the small and hard to study birds, penguins, are almost inaccessible due to their location in extremely harsh and cold temperatures. Now thanks to this new technique, scientists have been able to take the first ever penguin population census from space. To their good luck, penguin populations in the Antarctic are appearing to be expanding with more Emperor penguins than ever before. Although this does not solve the global warming problem this will allow scientists to monitor these penguins and gather information on the species that they never would have been able to get before.

            This break through in satellite technology is a huge step forward in technologic engineering. This will enable scientists to monitor large amounts of species, mainly endangered ones. They will be able to track these animals and collect information on trends in the populations and provide help if a problem arises that is clearly hurting the species. With this newly gathered information scientists will be able to formulate ways to help and provide to these endangered and struggling animal species. Also this will help scientists observe animal behaviors and how they move about in their given landscape.  Clearly this satellite innovation will have a dramatic and long lasting effect on the animal population as well as the environment. 

            Although this was a very interesting and informative article, I do think a few things could be improved.  For example, I think the author could have gone into greater depth with explaining the species of Emperor penguin and giving them proper background coverage, as they were the species that was solely focused on throughout the article.  Another thing I think the author could have done better is giving a better explanation of what else the satellite is used for and what has been done with penguins with the satellite opposed to just stating that they had taken pictures of these massive colonies.  Only a few spots lacked a proper bulk of explanation and information, however, in no way did that ruin the article.  It was very interesting and this new invention will definitely become very widespread in the years to come.

http://news.nationalgeographic.com/news/2012/04/120413-emperor-penguins-survey-antarctica-animals-space-science/

Determine a stems cells fate

The article ‘Determine a stems  cell fate’ describes the new discoveries with what happens to a stem cell at the molecular level that causes it to become one type of cell and how does it become committed. Jingli A. Zhang led up the study a graduate student in Rothenberg's lab. 

The researchers investigated the multipotent hematopoietic precursor cells to find that all of the genes that play a role in transforming the precursor cells into committed T cells, in the immune system. . Researchers also tracked genes that could guide the precursor cells to various alternative pathways. The results show when they become committed and how the T-cell-development process turned off the genes promoting alternative fates.

Five stages have been studied in the cascade of molecular events that yields a T cell. Transcription factors are what they have identified during this process, including many that code for regularity proteins which turn \ particular genes on and off. The discoveries led to that during the second and third a regulatory shift occurs when the T – cell commitment sets it. During this a lot of transcription factors that activate genes associated with uncommitted stem cells turn off while others that activate gene needed for future steps in T- cell development.

A critical component that makes genes possible to be expressed at a particular time is the expression of transcription- factor genes. Parts of the genes are served as docking sights for the genes in identifying the control sequences linked with certain regions of DNA as a result of the action of transcription factors, affecting how hard or easy it is for neighboring gene to be turned on or off. Rothenberg's group has paved the way for researchers to identify control sequences for many of the genes that turn on or off during T-cell development, by identifying DNA regions where epigenetic markers are added or removed. 

This article relates to life and us because we are made up of cells. I thought that this article also went well with the topic of us learning about the cell in class.

I found ‘Determine a stems fate’ very interesting, before reading the article I didn’t know anything of determinating the cells fate before reading this article.

"Determining a Stem Cell's Fate." Biology News Net. California Institute of Technology, 12 Apr. 2012. Web. 17 Apr. 2012. <http://www.biologynews.net/archives/2012/04/12/determining_a_stem_cells_fate_.html>.

http://www.biologynews.net/archives/2012/04/12/determining_a_stem_cells_fate_.html

How Useful Is Whole Genome Sequencing to Predict Disease?

                This article presents the findings of a study published online April 2 in Science Translational Medicine that full genome sequencing might not even be so helpful in predicting disease, as few diseases have strong enough genetic components to make it a reliable way to assess individual risk. The study’s co-author,  Bert Vogelstein, director of the Ludwig Center for Cancer Genetics and Therapeutics at Johns Hopkins University, said that most common diseases, including heart disease and stroke, do not result from a single-point mutation, or even a combination of them. These kinds of diseases also involve one's own lifestyle and environmental exposures. Vogelstein and his colleagues set up an experiment that examined genetic and health data from large existing registries of tens of thousands of identical twins. They looked for 24 common health issues, including some cancers, along with autoimmune, heart and neurological diseases. Though we do not yet have a perfectly clear picture of all how all of these conditions could potentially spear in genetics, the researchers figured out a model that acted as if we did already have that knowledge for the purpose of testing “the upper boundaries” of what we might be able to learn from the genome alone. Still, most people will wind up getting a “negative” (meaning low risk) result in terms of their risk for most diseases. However, for about half of the diseases most of individuals from the registries who would have received a "low-risk" result from a whole-genome sequence would have ended up getting one of these diseases anyway, meaning that this testing wasn’t going to help much. Nonetheless, they found promising results in studying twins’ chance for Alzheimer’s: those in the study whose genomes showed a low risk for Alzheimer's, for example, did have about a 12 percent ( much, much smaller) risk than that of the general population. They also note that one of the keys to improving disease risk prediction will instead be to collect even more information regarding nongenetic factors because most disease contributor factors are nongenetic anyway.

                Clearly this study is very relevant to society and all of our lives. People are really interested in disease prevention, and they always will be. People do often think that genetic factors can give solid readings of their chances for contracting diseases, but this study shows that studying the human genome really doesn’t help much for what it’s worth and probably won’t in the future because these diseases are often due to lifestyle differences or external exposures rather than destined to show up in an individual because of his or her genetic makeup. Furthermore, the researchers note that by better understanding the limitations of genome-wide sequencing, researchers and policymakers might be better able to direct funding and efforts to areas, such as Alzheimer's disease, where a person's genetic profile might actually have an effect on their likelihood of getting the disease.

                This article was quite well done, and I think this study is particularly relevant in terms of what  people need and want in our society, as well as the fact that it brings our idealism about uncovering the key to the eradication of all terrible diseases down to earth: we simply don’t have the science yet, and even when we do, it’s likely it will only help in a pointed area. I thought the discussion about the Alzheimer’s risk was particularly important, though I would have liked to see more numbers for that. Also, I think the writer could have gone further into detail about other diseases besides Alzheimer’s for which full genome testing would actually be useful and described the model that the scientists developed to test high risk or low risk: it wasn’t technically necessary, but the nebulousness , made it harder to conceptualize.

ARTICLE LINK:

http://www.scientificamerican.com/article.cfm?id=whole-genome-sequencing-predict-disease&page=2