Climate change

Submitted by imadjidov on Fri, 09/20/2019 - 01:49

Over the past 40 years, the bird population in the United States and Canada has declined by 29% or almost 3 billion birds. Research was conducted by American scientists at the Cornell Laboratory of Ornithology. According to the results, of the 3 billion dead birds, 90% belong to common families, in particular sparrows, finches and swallows. They play an important role in food chains and support the functioning of ecosystems, such as pest control.

The study noted that bird losses in North America are similar to bird losses in other parts of the world. Co-author of the study, John Sauer, believes that the main factor that affects the extinction of birds is habitat loss, including due to intensive farming and urbanization. Scientists suggest that further climate change will worsen the situation.



Synaptic Plasticity PP

Submitted by zalam on Fri, 09/20/2019 - 00:52

Synaptic plasticity is a concept that had always seemed interesting to me. Even after birth, your brain is capable of changing its connections and wiring. It best described by Donald Hebb's words on long-term potentiation: "Neurons that wire together, fire together". The concept of long-term potentiation involves three stages: input, induction and expression. During the input period, the presynaptic neuron fires a single action potential. This causes a small post-synaptic potential. During induction, multiple action potentials are fired repeatedly along the presynaptic neuron, leaving very little time for the postsynaptic neuron to fire a small action potential and then die down. As a result, the postsynaptic potentials keep bulidng up and reach a threshhold where the neuron is depolarized, leading to an action potential to be fired. This event of accumulation of potentials over a brief period of time is called temporal summation. Finally in the last stage, we see that a single action potential, like the one in the first stage, is able to cause a full action potential called the excitatory postsynaptic potential. This is essentially how we learn. If we keep introducing the same stimulus over and over again, the wiring in our brain adjusts to fire a strong action potential. However, our brain does have a capacity for how much we can learn. The neurons can get too saturated with new wirings if there is no way to reverse this process. Thus, certain wirings start getting weaker by time and this is called long term depression. This would be another way of saying that we are slowly forgetting what we had learned. 

I thought that I write an explanation of what flow cytometry is

Submitted by ziweiwang on Thu, 09/19/2019 - 23:48

I actually almost laughed out loud, during class when I saw the article title How I learned to love flow cytometry. Because it was so accurate of an title. Over the summer, I actually got some experience working with the machine, and it takes quite a long time to get used to, and it was one of the things that I never quite got used to. I got used to handling mice before even being able to explain how flow cytometry work properly. Being fair, it hurt a lot less to handle flow cytometry. The machine had a lot of problems, but biting the people handling them was not one of them. to be honest, I still can't explain it very well, and if I don't write it down somewhere I will probably not be able to remember any of it. 

Basically, flow cytometry is when cells are labeled with specific antibodies and tags then the cells are passed through the machine to detect certain proteins such as antigens and other proteins. when the cell is passed through the tube the computer shines the laser at it and record the size of the cell, the weight of the cell, and what label it has. the scientist using the machine can change the graphs so that they can make a bunch of graphs that suit their needs. one thing that can be done is to show whether the cells have clumped or not. another is how much of one cell is expressing a certain protein. By manipulating the graph, the researcher can see that in certain cell population such as t regulatory cells, certain protein is missing in mice that are missing certain mutations. Because there are not as many cells that are needed for this, the technique is popular both in the lab and in a clinical setting. 

how I got the picture before I forget.

Submitted by ziweiwang on Thu, 09/19/2019 - 23:29

To take this picture, I walked to the closest vendor that was selling Spinacia oleracea leaf.  the leaf that I got specifically was baby spinach, not of the larger variety. I specifically chose a leaf that was not previously damaged and had a relative rounder leaf, and it was still fresh enough that it did not wilt when held up, even at the edges.  I then took a picture of the leaf, holding it by the stem, against a gray background and took a picture.  I held the stem so that most of the stem was covered up by my hand and the only the leaf was visible. When I was taking the picture, I held it up close enough that the leaf was relatively center and filled almost the entire picture rather than just around the corners. the picture that I took was slightly blurry, and as a result, the full-color difference between the differing part of the leaf was only slightly visible.  Then I took a bite that was large enough to cover half of the leaf, held it up again much in a similar position but with further distance so that the hand and the leaf fit within the bottom half of the picture, which was in portrait mode.  and took another picture with a similar background.  

While it does not matter where the plant leaf was obtained personally I obtained the leaf at one of the dining halls at University of Massachusetts Amherst. Specifically, the one that I have pointed out in the map. The gray background was the high chairs that they had at the dining halls.  However, as long as the leaf is baby spinach and the background is a similar color, there should not be any reason why the picture would be different. 



summary of methods from a study on LDL

Submitted by ziweiwang on Thu, 09/19/2019 - 22:55

In the study with the LDL, 25 patients with high blood LDL, was gathered. The 20 of patients had high blood cholesterol, but none of the patients were likely to have FH.  Five patients with heterozygous FH has gathered apart from the 20 patients. The participants with heterozygous were determined by their high LDL blood level in the blood which was much higher than the patients. The 20 participants were given two types of labeled LDL. The first type of LDL that was used is the patient's own LDL, which was extracted by their blood, labeled and inserted back into the body. The other type of LDL was obtained from first-year medical students who had normal blood cholesterol levels and fit the criteria for giving blood. The patients were then all admitted to the hospital for the study and were given a relatively high-fat diet.  The LDL turn over was studie by taking blood from taken from the donors and removed and the amount of the two labeled LDL was detected. 

The result of the study is that while in patients with Het FH, neither LDL was absorbed well. In some of the 20 patients who did not have FH, the patients had a much higher turnover rate of medical student's LDL compared to their own LDL. This indicates that the patient's own LDL is not structurally compatible with the LDL receptors in the cell, and indicate that the patients were unable to make normal LDL. since the absorption of the LDL in the blood causes the cells to decrease the production of LDL, it is not unreasonable to say that the unusual structure of the LDL protein is the cause of high cholesterol in these patients. If that was a true one of the ways that it can be treated is to inject LDL from someone else in to their blood. However, this treatment is not cost-effective, since the patients who have a misformed LDL inly have a slightly higher pressure than normal. 


Submitted by nskinner on Thu, 09/19/2019 - 22:16

To draw blood from a canine patient from the cephalic vein you must first gather the supplies you need to collect the samples. You need isopropyl alcohol, a syringe and needle combination; usually with a 22g needle, and the proper tubes to put the sample in. Second, put the patient in proper restraint. A technician should be holding the patient and occluding the vein of either one of the front legs. The technician drawing the blood should then wet the area over the cephalic vein with isopropyl alcohol. With gloved hands you should then be able to feel the cephalic vein by tapping and rolling your finger over the area where the vein should anatomically be; which is usually half way between the paw and the elbow on the cranial side of the leg. You should then uncap your needle. While holding the leg in your non-dominant hand you should use your dominant hand to insert the needle, bevel up, into the vein. A flash of blood should appear in the hub of the syringe. You should then gently and slowly pull back the plunger of the syringe; blood should fill the syringe. Once you have the desired amount, which for most dogs is usually going to be about 3ml, you can place gauze over the area where the needle had entered the skin quickly after removing the needle from the skin. The person restraining the dog should then take over holding the gauze and applying pressure to stop the bleeding. The technician that has just drawn then blood should recap the needle using a one hand technique for safety and remove the needle from the syringe. You should then uncap the desired tubes to place the blood in and plunge the blood slowly into the tube. Replace the cap to the tube.By removing the cap of the tube rather than piercing the tube you avoid hemolysis of the sample. If the tube requires inversion, invert the tube as needed. You then should dispose of the syringe and needle in a sharps container. At this point most patients can now remove the gauze from their leg. If there is still bleeding, you can apply a pressure bandage for about 10 minutes.  

Midterm Paper ideas pt 2

Submitted by rbudnick on Thu, 09/19/2019 - 21:35

I think I have decided to write my paper on using seaweed farming to help reduce a country's environmental impact. In the coming years, it is imperative that the amount of excess carbon in the atmosphere is reduced, which is where seaweed faming comes in. Seaweed farming is regenerative farming, which is so sustainable it actually helps inprove the area it's grown in. The seaweed can be grown on land or in the ocean, providing benefits to both and returning some of the carbon back into the plants and ecosystem. Not only will the farms be small and produce little waste, but it will also help local farmers and small businesses which already or plan on creating seaweed farms. Importantly, I've read that seaweed farming does not use fertilizer or pesticides, and of course no land will need to be cleared since it is grown in salt water. On top of that, seaweed and kelp help reduce ocean acidification which has been an increasing problem associated with worsening climate change. When you think about it, widespread seaweed farming will help a few of the world's biggest problems: climate change, economy, sustainablility, and world hunger. 

study summary

Submitted by ziweiwang on Thu, 09/19/2019 - 21:27


    The question that is posed in the research is what effect does differing hemoglobin from patients with sickle cell anemia on lung epithelial tissue.

The data tells us that sickle cell hemoglobin causes the cells to oxidative stress. In addition, the epithelial cells fail to function as a barrier when the cells were exposed to HSE and Hbs. While the Hbs and HbE ferryl hemoglobin caused bioenergetic impairment in cells,  a similar result was observed in HbA from healthy people

The experiments concluded in the discussion that while all of the hemoglobin variants caused damage to the cells, the Hbs and HbE were less stable than HbA, and as a result, were more likely to lead to heme loss in the proteins. In addition, Hbs and HbE both allowed higher permeability of epithelial cells, but not in HbA. The conclusion of the data assumes that while free Hb in the blood by itself is damaging. However, if the Hb was of the variant where the Hb is less structurally sound, as in dysfunctional Hb, there was more damage to the function of other cells. 


The impact on SCD is that while it was thought that just the presence of free Hb in the blood is damaging, because of the protein instability of Hb in patients with sickle cell anemia, their Hb are more likely to be damaging to the lung epithelial cells compared to Hb protein from someone who is not ill. The fact that it is more damaging indicates that when researching the treatment of SCD symptoms, a model that uses a normal Hb would not be an accurate representation of the symptom of people with SCD. Knowing this would create a better model for a scientist to use to research treatments. 


mechanism of a study

Submitted by ziweiwang on Thu, 09/19/2019 - 21:26

The first experiment that they did, the experiment involving adding hemoglobin to lung epithelial cell culture answer the question by modeling what happens in the body If there were Hemoglobin S, Hemoglobin SE, and hemoglobin A, normal hemoglobin) was floating in the bloodstream. In the experiment, they measured the permeability by having the epithelial cells grow on a membrane rather than in a flask. Then they measured the permeability of the culture by adding media containing dextran on the top layer and measuring how much dextran there were in the bottom layer. At this stage, they also added hemoglobin to the top layer to see if the hemoglobin had any effect on the permeability of the cell layer. The cells were then washed and immunoblotting and microscopy were done on the cells to visualize how the hemoglobin had an effect on the cells. The researchers also measured the amount of oxidative stress that the cells had gone through by measuring the epithelial lipid hydroperoxide levels.  Mitochondrial Bioenergetic and glycolytic levels were also measured to assess the damage in the cells. The procedure of this experiment is simple in the sense that they had a model and exposed the model to the same environment as those that would be found in sickle cell disease patients, and assessing if there were any damage that the cells sustained. While this experiment does not exactly measure the dysfunction that is present in the hemoglobin (as for example, exactly how and why it is dysfunctional), it measures what the hemoglobin dysfunction causes in other cells (what does the dysfunction of the protein does to other cells?).



Submitted by mpetracchi on Thu, 09/19/2019 - 20:34

Once all three of the images have been gathered I opened google drive, clicked on the new media icon, and hovered over the tab labeled more. A second menu popped out to the side including google drawings. I opened the program which has an empty workspace with a checkerboard pattern in the center workspace. From here I imported the three images from before into the workspace by dragging and dropping them in. I oriented them left to right as follows: Close up shot, distant shot, map. The workspace itself is 10 inches across and the figure should fit that space exactly. I made the close-up image 2.7 inches wide by 3.61 inches tall, the distant shot 2.7 inches wide by 3.61 inches tall and the map is 4.6 inches wide by 3.61 inches tall. Overlaying the map image, I circled the approximate area where the leaf was found by clicking the 'shape' icon and adding a circle. I selected the border color icon and changed the color to red. I selected the arrow icon and added an arrow pointing towards the circle starting from the bottom right of the map. The figure looks as follows. Three images left to right including a close-up shot, distant shot, and map and a red circle identifying where the plant was found with an arrow pointing towards it. Export to a .png file by clicking ‘file’, then ‘download’, and select ‘PNG image (.png)’.


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