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Lens are defined as a piece of transparent material that is designed to take in parallel photons. Many people may think of contact lens that individuals, who are farsighted, might wear as a correction for their vision. Contact lens correct farsightedness by converging light rays and increase the eye’s ability to focus. Converging lens are thicker at the middle while diverging lens are thicker at the edges and both types exist depending on what the lens is trying to correct. Since contact lenses rest directly on the eye, they are much thinner than eyeglass lenses that otherwise need to be resistant. They are also shaped to be thin and flexible to fit comfortably on the cornea of the eye. Lastly, lenses are also made to be gas-permeable to allow oxygen to reach the cornea. This explains, why contact lenses are not recommended to wear over a long period of time and advised to wear glasses once in a while to allow the eyes to ‘breathe’.

Chapter 12 of the Sixth Extinction, The Madness Gene, dealt with the various theories that have developed overtime to explain the Neanderthals themselves and also why they disappeared so suddenly. In a larger spectrum, Elizabeth Kolbert addresses the role that humans may have contributed in wiping out the closely related Neanderthals. Hence this chapter shows a bleak portrait of human nature, suggesting that humans are capable of destroying even beings that resemble themselves closely enough to breed with. In a both sad yet fascinating aspect, Kolbert explains that, “before humans finally did in the Neanderthals, they had sex with them. As a result of this interaction, most people today are slightly- up to four percent- Neanderthal” (238). The chapter begins by introducing paleogenetics, in which it is sometimes possible to examine prehistoric remains and find fragments of DNA. Using DNA samples, scientists like Pääbo can reconstruct what long-extinct creatures looked like, and their genome. Pääbo’s goal specifically is to sequence the entire Neanderthal genome, in order to lay out the human and Neanderthal genomes to find where they diverged.

Candida albicans are fungal pathogens that can be infected in humans. It can grow in various forms either a yeast form, which is unicellular or pseudohyphae form. Candida albicans are harmless in general, but can lead to diseases when they over grow. The Candida albicans are found mostly in patients with HIV, transplant recipients, and chemotherapy patients. The morphology of Candida albicans depends on the environment they are placed. Temperature, pH, salt concentration are all factors that determines the appearance of Candida albicans. Through a method called transition, Candida albicans can easily change their morphology. Unlike eukaryotic cell’s gene regulation, in bacterial cells the environment can easily manipulate the gene they are in.

The methods section of a scientific article allows researchers to determine the validity of a study based off of replicability. When developing an experiment, certain factors that may affect the replicability of a study should be controlled in an effort to minimize discrepancies between iterations. The methods project attempts to practice and develop these skills, as well as distinguish between observation and inference through the examination and replication of a multi-panel figure illustrating an interspecific interaction.

    The interspecific interaction between mallard ducks (Anas platyrhynchos) and canada geese (Branta canadensis) will be examined in this project. At UMass, mallard ducks and canada geese are commonly found around or near the campus pond during the winter months. As a result, both species often interact with each other in multiple ways. The most commonly observed interaction between these two species is the sharing of space on the campus pond. These two species are easily photographable together since they are typically not shy, in the same general region, and quite prevalent. Therefore, images of them in this environment would be feasibly replicable.

Elements of this process to take into account for replicability include photography, location, weather, time, and levels of specificity. The location of the ducks and geese are on the campus pond, which is in the center of campus, making it easy to find. Due to its vast size and the mobility of these two organisms, a camera with zooming capabilities should be chosen to document their interaction as well as the organisms individually. The ducks and geese are typically observed near the end of the campus pond closest to the Fine Arts Center, either swimming or along the shore. It may take a while for the ducks and geese to trust a human enough to get close for pictures. If it is raining or snowing outside, the ducks and geese are away from the campus pond, so photography should be performed on a day with fairer weather. Pictures of the geese, ducks, and their interaction should be made as broadly as possible to maximize the chances of successful replication. Out of these three images, the interaction especially should not be particular about exact location on the campus pond due to the mobility of these organisms and the size of their environment.

In the old times, naturalists did not have a solid explanation on how birds migrated. Aristotle found out that cranes migrated seasonally. Based on discoveries and technology, we all know that land birds fly one place to another depending on the seasons. When migration season happens in North America, birds usually to move north to south direction. It is known that most migratory birds breed in the south and returns to the north. Birds living in the southern hemisphere will not migrate to the north as much as the northern birds travel. Some birds only travel during the day, others at night, or even both such as the waterfowl and shorebirds. Birds can fly as high as 2000-4000 meters and sometimes much higher and every bird has different altitude level that they can travel.

I have a biochem exam this week so I have been using my thirty minutes of writing each day to go further in depth with topics that I don’t fully understand and want to get a better grasp on. I went to a review session for it to try and help me with some of the topics and one of the questions that the SI asked us really confused me. She asked if the pKa of an amino acid could change and then said the answer to the question was no. She started to explain why it was no then said the question didn’t make sense and scrapped it all together. I made a note of it and tried to figure it out when I got back home. It turns out that in fact the pKa of amino acids can be altered. That is the pKa of the R-group. The pKa’s get altered when a neighboring R-group, which is ionizable, has a similar pKa. This means that the R-groups will be similarly protonated at similar pH levels which means that they will have similar charges. This will cause the R-groups to repel each other and can alter the folding of a protein which will alter the structure. So if an amino acid like glutamic acid (pKa of 4.25) is located close to aspartic acid (pKa of 3.86) they will have the same negative charge at around the same pH. If they are in a cell at physiological pH of 7 they will both be fully deprotonated and have negative charges, this will cause the two groups to repel. Since aspartic acid has a lower pKa it will become deprotonated first and in an effort to prevent repulsion the pKa of glutamic acid will be raised so it doesn’t acquire a negative charge from deprotonation. This helps maintain protein structure.

Introduction

In this exercise, the methods of one student’s interspecific interaction at UMass was followed by another classmate to replicate the work as accurately as possible. Four different images of a species of yellow flowers were taken and observed. The images were then arranged in a panel with four labeled pictures a, b, c, and d.

Observational Differences

The first difference observed between the two figures are the sizes of the figures and the sizes of the individual panels. The first figure on the top is smaller but the proportions appear to be the same as the second figure because the images do not look stretched or squeezed. The quality of the two figures is not the same as the figure on top appears to have a better quality image than the figure on the bottom. In terms of the lighting the pictures, they are similar although the first figure has more contrast between the colors of the yellow flower petals and the color of the brown center with the small clustered seeds.

In the second panel, the ruler is not measuring the same aspect of the flower. The first figure appears to be measuring the length of one yellow petal whereas panel b, in the second figure, has the ruler placed above the flower without touching it and does not cleary measure from one specific point to another. Also, more of the ruler is shown in the first figure. In panel c, the angles in which the pictures were taken are slightly different because the picture in panel c was taken as a higher viewpoint. This further affects what is visible in the background of the pictures.

Lastly, panel d does not match one another’s images. Panel d in the first figure shows two flowers without petals with leaves on stems in the background and panel d in the second figure shows multiple flowers with bright yellow petals with the ground made up of wood chips in the background.
 

Inferences and Discussion

The several differences mentioned could be a result of different factors of the environment and the methods of how the pictures were taken with a camera and composed in an art application. The proportions of the pictures were most likely discussed but the specific dimensions were not. The pixels could also be different and result in different sizes.

It is also evident that the two students did not have the same quality camera or photography skills, which contributed to the difference in image quality and frame.

In panel b, there most likely were insufficient details on what exactly to measure on the flower and whether to measure it from the side or the top of the flower. In addition, panel c shows differences on the view at which the pictures were taken as panel c in the second figure was taken more from the side as opposed to a slightly birds eye angle.

The last panel was not replicated well, which may have been caused by lack of details, confusion, or not being to find exactly what the student has originally captured. Moreover, the flowers in the first figure may have been trimmed and removed completely if they were dried out.

An estimated 10-15% of pancreatic adenocarcinomas are attributed to genetic causes (Klein 2012). Germline mutations in the BRCA1 and BRCA2 genes are the most common, occurring in 13-19% of families (Lal et al. 2000). The PALB2 and ATM genes are also some that are commonly mutated in hereditary pancreatic adenocarcinomas (Jones et al. 2009). These mutations could be further examined in an effort to detect pancreatic adenocarcinoma earlier in those that are at higher risk. An early screening mechanism of detecting pancreatic adenocarcinoma in patients, regardless of family history, would be significantly beneficial in increasing survivability.

In terms of resistance to the developed ONC201 liposome treatment, a fluorinated-ONC201 analogue, ONC212, has been developed and has shown preclinical efficacy in melanomas and hepatocellular models. A study demonstrated ONC212’s efficacy in in vivo models with ONC201-resistant tumors (Lev et al. 2017). The researchers found an effective combination of ONC212 with the inhibitor AG1024 in vivo for pancreatic adenocarcinoma. ONC212 is effective in pancreatic adenocarcinomas alone and in combination with other drugs such as 5-fluorouracil, irinotecan, oxaliplatin, and RTK inhibitor crizotinib (Lev et al. 2017). This may serve as a backup treatment if resistance to ONC201 develops, and another synergistic combination may be developed from these drugs.

It is a common misconseption that arteries carry oxygenated blood and veins carry deoxygenated blood. This is true in the systemic pathway, where blood is delivered to the body, but it is not true in the pulmonary pathway. The pulmonary system is when the blood is delievered to the lungs. Here deoxygenated blood is carried by arteries and oxygenated blood is carried by the viens. Ultimately, viens carry blood towards the heart and arteries carry blood away from the body. The arteries have a greater amount of pressure than viens due to the fact that blood is pumped out of the heart. Because of that, there is also significantly less blood volume in the arteries than the viens. 

          Due to the deterioration of coastal wetlands in the United States, efforts have been made to devise effective conservation strategies to halt their destruction and potentially aid in their recovery. Wetlands are not only among the most biodiverse habitats, but can also serve as natural speed bumps to approaching hurricanes by starving them of warm ocean water and creating physical barriers to surging flood waters. However, in the last hundred years, the combined forces of human development and increasingly extreme storms have turned thousands of square miles of wetlands in the U.S. into open water.  One strategy to address this issue is government regulation. By 1984, over half of all the wetlands in the U.S. had been drained or filled for development or agriculture. Congress responded to these figures by passing two wetland conservation and restoration programs administered by National Resources Conservation Service (NRCS) to slow or reverse these trends. These two programs are the Wetland Conservation Provisions which was authorized in the 1985 Farm Bill, and the Wetlands Reserve Program which was later authorized in the 1990 Farm Bill. These bills put into law restrictions on pollution, such as requiring more strict run-off protocols, which resulted in reduced agricultural impacts on wetlands. Through these two programs, NRCS works with farmers and ranchers to maintain or increase important wetland benefits, while ensuring the farmers' ability to continue to produce crops. Another strategy is to better communicate the economic benefit of healthy wetlands, in order to incentivize the private sector to take action. Using the latest modeling techniques, researchers from the conservation, engineering, and insurance sectors studied the impact of Hurricane Sandy in the northeast United States in 2012, when New York and New Jersey were badly hit by storm surges. The study determined that more than $625 million in property damages were prevented during this catastrophe due to wetlands along the Northeast coast. Promoting these advantages of wetlands may result in greater consideration in coastal development and habitat restoration decisions, and may provide greater incentives in the private sector to design their development projects in a sustainable way so as to conserve and restore these natural habitats.