The presymptomatic phase of kuru lasts, on average, 10 to 13 years but incubation time can range from 5 years to 50 years (Collinge et al., 2008). Mean clinical duration of the disease is 12 months with a range of 3 months to 2 years (Collinge et al., 2008). Kuru infection presents itself in three progressive stages: ambulatory, sedentary, and terminal (Alpers, 2005). The primary physical symptom of the disease, cerebellar ataxia, worsens as the disease advances through these three stages(Gajdusek, 1957). In the ambulatory phase, patients demonstrate a loss of muscular coordination though they are still capable of speaking and moving around (Gajdusek, 1957). In the sedentary stage, infected individuals show stronger ataxia that manifests as major dysarthria, frequent, excessive bursts of laughter and the impossibility of unassisted movement (Gajdusek, 1957). At the terminal stage, infected individuals can no longer sit without support, the ability to speak is lost, urinary and fecal incontinence is common, dysphagia begins, and many develop ulcerated wounds that are prone to infection (Gajdusek, 1957). Death occurs shortly thereafter either due to wound infection or terminal static bronchopneumonia (Gajdusek, 1957).
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The cell is the foundation of all life. This fundamental unit has given rise to a vast array of organisms, some unicellular and some multicellular. But what if we changed this view, instead considering these life-carrying elements as small machines? Jason Kelly, CEO of Ginko Bioworks, seeks to make this kind of thinking into a reality. Kelly views cells much akin to that of a computer, with a coding language made out of adenine, cytosine, guanine, and tyrosine. As Kelly puts it, "synthetic biology is programming cells like we program computers, by changing the DNA code inside them"1. Ginko has already implemented this methodology in a variety of fields, such as fragrances and flavorings. One of their largest bioengineered flavorings is synthetic mint, which Kelly believes is the "biggest flavor ingredients out there"1. Kelly states that the next target of this technology is the fertilizer industry, replacing nitrogen-based fertilizers that create runoff and greenhouse gas emissions with simple seed treatments. Through synthetic biology, Kelly hopes that his company will innovate and provide novel solutions to the most environmentally unfriendly and expensive problems we face in society.
(1) Weber, J. (2019, November 6). Ginkgo Bioworks CEO Wants Biology to Manufacture Physical Goods. Retrieved November 8, 2019, from https://www.bloomberg.com/news/features/2019-11-06/ginkgo-bioworks-ceo-w....
The Gospel of Germsis a social history of the implications of the germ theory on Americans. It provides a valuable and absorbing window into how the American society, with the introduction of the germ theory, saw the world with new eyes. Major themes of this book are the measures adopted by Americans to avoid germs and how these radical changes served to fortify societal distinctions. The countless stories of the victims of unseen killers shocked me to the core. In each of them, I found a little of myself. However, a disadvantage of the author’s work is her inability to reflect the subjective thoughts of scientists on the issues covered. Tomes is limited to presenting the facts, but not the essence of the scientific discoveries. Furthermore, another problem with The Gospel of Germsis that it focuses too much on the Progressive Era, downgrading the social movements of the later era as less important. Moreover, Tomes failed to recognize the class differences among women. As history tends to forget that class differences have always affected the lives of women. Furthermore, Tomes does not mention the impact of the germ theory on African American women. The gospel of germs highlights the media as an important actor in the public health system, that can catalyze action at the national and local levels. This was particularly true with respect to diseases. The greatest challenge of the early 20-century germ gospellers was to convince Americans that tuberculosis was a communicable disease. As a result, many anti-tuberculosis societies relied on pamphlets, popular lectures, and newspaper articles to promote public awareness of the disease. Through the media, the germ panics reflected the notion that contact with the diseased and the things they touched was bad, so it helped reinforce feelings of class prejudice and racism.
In this research paper, the research shows that the disease in the photoreceptor cells also affects the cells that are around those cells, this changes how the disease should be studied. In the study, the conclusion of the experiment is that the loss of photoreceptors changed the number and morphology of the glial cells such as astrocytes and Muller cells. The change in the number and morphology of the glial cells affected the retina and as a result, may be an important part of the retinitis pigmentosa which was previously only thought to affect cone cells. Because the disease affects other cells and not just the cone cells, there is a need in the cellular and tissue level model to mimic how the cells behave in the disease. In addition, any further research into the treatment for the disease needs to take into account how the treatment would affect the cells surrounding the photoreceptors. For example, if a drug only really works to fix the one problem that is wrong with the mutated protein, this may not necessarily fix the damage that has already present in the surrounding tissue. By taking into account these issues, the treatment will have a higher chance of performing well in the clinical trials, leading to a faster treatment that can be released into the market.
The objective of our proposal is to create a phylogenetic tree examining the possibility of using the HOXC gene as an indicator of the phylogeny. One specific aim of the proposal is to identify highly conserved genes that are present in vertebrates. In preliminary work, we found that one example of a highly conserved gene is the BOP1 gene present in ribosomal DNA. Further research done on HOX genes has noted that the duplication of HOX clusters is shared by all vertebrae (Ruddle et al. 1994). The statement motivated our group to propose that the HOX genes express little variation in vertebrae, and test the statement by knowing how consistent this data would be if we were to expand our subject of interest to a whole kingdom, rather than specific subjects used for their evidence (chicken, zebrafish, Xenopus, and newt). We will now look into HOX genes to see how similar or different expression of the HOX gene is throughout the Animalia kingdom.
From small mosses to large trees, all flora on earth requires water to survive. So what were to happen if an environment experienced an extreme drought? Could life survive? Some plants have developed methods of preventing their death due to water loss, a state which is also known as desiccation. Living cells would normally shrivel up and cease to function, however, some have become tolerant to that stress. These desiccation-tolerant plants produce proteins and morphological changes in response to low water levels. In a desiccation-tolerant plant, its cells synthesize sugars such as trehalose and transport them to cells who are experiencing shrinkage. Trehalose replaces the water and maintains membrane integrity. Another problem desiccation-tolerant plants face is how to repair damage to UV light and radiation when in this low metabolic state. The solution; produce pigments and extracellular sugars to block the incoming rays before they become a problem.
The alcohol industry has been growing exponentially, as college students and young adults are asking for more and more. This industry has been alive for as long as our whole family lineage has been alive for. In fact, alcohol has been around Before Christ. The Babylonians worshiped a wine goddess as early as 2700 B.C. In Greece, one of the first alcoholic beverages to gain popularity was “mead”, a fermented drink made from honey and water. Greek literature is full of warnings against excessive drinking. This shows us that alcohol has been around for a very long time, but when did it become an epidemic? Alcohol is a psychoactive substance with addictive properties, just like nicotine. As above, we can see that it has been widely used in many cultures for centuries. This substance not only has detrimental physical health effects to the individual, but it has psychological effects, and can harm other people such as family members, co-workers and strangers. In fact, alcohol is now the 3rd leading preventable cause of death in the United States, with an estimated 88,000 people dying from alcohol-related causes every year.
The stability of slopes is correlated with the vegetation on that slope in regards to stability (Fan, Lai 2104). The root systems of plants play a pivotal role in the stability of a slope. Does the slope also determine what vegetation is present and for how long? This idea my help determine if trees in different habitats tend to be different sizes. The steepness of a slope can create different habitats. The difference in these habitats can be related to the variance in the steepness of slopes. It is well known that generally the larger the radial measurement of a tree is the older that tree is. A series of small trees could indicate information about the mortality rate of that species. Mortality rates may depend on the slope steepness and elevation (Bigler, 2016). This notion can be related back to the variance in tree size and certain habitats. Steeper slopes have smaller trees due to higher mortality rates of larger trees.
When the sun heats up several water bodies, water vapor starts rising up due to its low density. As it reaches a higher altitude, the temperature starts to cool down. This drop results in the vapor to condense and form clouds above. A more simplified version can be shown using a cloud in a bottle. Adding a small amount of water (or to make the process much faster - ethanol) in a 1 litre plastic bottle would represent the process in a closed system. Using a rubber cork, the nozzle of an air pump can be secured in place. Once everything is set, air is pumped into the bottle with water/ethanol. As more air is pumped into the bottle, the pressure inside starts increasing. Since PV=nRT, the temperature also starts to rise inside. This equates to the water rising once the sun heats up the seas, lakes, rivers etc. As soon as the cork is removed, there is a pop sound followed by a sudden appearance of fog, which represents the cloud. When the cork is removed, there is a sudden drop in pressure, followd by the drastic drop in temperature that rapidly cools down the heated air inside, thereby causing condensation.
HOX genes are a group of highly conserved genes in organisms that dictates their body plans. To determine whether HOX genes are a reliable indicator of phylogeny, we look to determine the reliability of the phylogenetic trees made using the HOXC gene and comparing it to the existing phylogenetic tree. The analysis would highlight differences in HOXC gene expression, which is gathered using MEGA software. The conclusion to this study will allow for the determination of phylogeny in a new species using the sequence of the HOXC gene.