Homeostasis (draft 5/6)

Submitted by kheredia on Thu, 09/12/2019 - 23:53

The body is constantly working to maintain a stable internal environment. This is more commonly known as homeostasis. When an imbalance occurs, a negative feedback loop is initiated to bring levels back to their normal function. Within a negative feedback, there are 3 simplified components: a sensor, control center, and an effector which executes a change to bring the imbalance back to a normal state. For example: when candy is ingested in large quantities, blood glucose levels rise. In this case, pancreatic B cells are both the sensor and control center. First, they sense the change. Following this, they respond to the high glucose levels by changing the behavior in cells to release insulin stored inside vesicles through the bloodstream to the effectors: fat and skeletal muscle. The effectors contain an insulin receptor, so that when the insulin does arrive, it binds to this receptor and causes a shape change which then triggers a reaction. Glucose transporters are signaled to be inserted into the plasma membrane of the cell and carry glucose via facilitated diffusion back into the cell to be stored. Thus, the result is blood glucose levels falling by leaving the blood and homeostasis is restored. 

Drosophila formation PP

Submitted by zalam on Thu, 09/12/2019 - 23:22

How does the body at an embryonic stage even know where to place all the organs in such perfect order? The drosophila's dorsoventral axis formation is a good model system to give us a general idea. At an early stage, the drosophila undergoes syncytial specification – in short, it is one cell full of nuclei in the same cytoplasm and they signal each other. Along the cytoplasm, there are genes creating proteins in different concentrations to establish different axes, including the dorsoventral axis. Gurken is a protein that starts off a signaling cascade that leads to the determination of the ventral identity. Dorsal protein controls the ventral identity of the embryo. Toll protein assists in transporting dorsal into the nucleus of the ventral side, where it acts a transcription factor to establish the identity. Another protein called cactus helps by preventing dorsal from entering and hence dorsalizing that end. To prove this theory, Roth et al had performed immunolocalization and Western blots to find location of the proteins in the wildtype, dorsalized and ventralized embryo. In short, it is the difference in concentrations of dorsal in the cytoplasm and the nucleus that creates the morphogenic gradient, which leads to the embryo to have a dorsoventral axis. In fact, the morphogenic gradient is a concept that can be seen in other settings too. For example, when our hands our forming, the the placement of our fingers from our thumb down to our little finger depends upon morphogenic gradient of a certain protein. 

protocol and procedure

Submitted by ziweiwang on Thu, 09/12/2019 - 23:10

I think that one of the most interesting things to me about being in the lab is how different it is being taught in classrooms. For example, there are many classes at the University of Massachusetts that teach about how to be in a lab and how to keep records.  The problem with all of this is that I have never really seen anyone who actually follows the protocol to the word. In the lab, especially in a high-pressure lab where there are so much pressure to publish, proper record keeping and following all the safety regulation can go out of the window, mainly because no one has the time to do that. Scientist's time is stretched into overwork as it is. No one wants to stay until 12 keeping records when they are already leaving the office at ten. scientists have actual lives to live, family to raise and bills to pay. I think that in this sense, the portrayal of scientists in the media is very much harming scientists. In the media, a scientist's career is their identity.  it is both what they do and what they are. Because of this, scientists, especially those in academia, is under pressure to overwork in order to achieve excellence. There is no time to achieve proper bookkeeping and safety precaution when putting out the results too late can mean the difference between funding and no funding. The fact that academics (postdocs) are not paid by the university means that they are under constant pressure to procure their own salary. 

so while I do think that it is absolutely important to have safety regulations,  I also think that it is absolutely understandable if those safety regulations are not met all of the time, because somethings just have to go in the name of efficiency and while the idea of trying to keep everyone safe is an honorable one, it is also absolutely impossible. resources are limited, and sometimes when the job needs to be done, something has to go, and it usually isn't the one where it pays everyone's bills.

Draft #7 Methods Introduction Draft

Submitted by ashorey on Thu, 09/12/2019 - 22:54

My initial ideas while developing my project are that I would like my phytophaging subject to be a caterpillar web in a tree where the caterpillars eat the leaves. I have witnesses this phenomenon many times at home, while driving on the highway staring out the window, and in the apple orchards in my grandparents' yard. The tree can be bright green but the very small caterpillars devour the leaves so that they turn brown and decay. Unfortunately, I have never seen this on campus and that means my subject may have to be different matter. I suppose I will first take pictures of trees/greens on campus that have evidence of phytophagy and then decide which to use for my figure. I will also research my specimen in the photos to ensure that I did in fact take images of eaten plant matter and not just some dead leaf. The format for the figure will include the first photo of phytophagy unlabeled on the far left upper corner and next to it with little spacing the distant photo with arrows highlighting the examples. Both photos will be squares and then the map will be oriented on the right upper corner and will be rectangular as to accomadate the shape of the UMass campus. The process of obtaining a guaranteed original map may be of issue, I might consider using illustrator to create my own image with reference photos of other similar maps of the campus. That way the map can include symbols or images of places of reference on campus and the photo of the phytophagy itself. 

Comparing Scientific Literature

Submitted by mpetracchi on Thu, 09/12/2019 - 22:43

The articles Smart behavior of true slime mold in a labyrinth and Monophagous leaf‐mining larvae of Stigmella (Lepidoptera: Nepticulidae) on birch: patterns and differentiation in exploitation of the host have many similarities and differences in their approach to writing a scientific article. 

Informative paragraphs in the introduction are similar. Both articles begin fairly broad and give basic information that leads the reader toward a more in-depth understanding of the subject and what the article is ultimately about. Each article approaches this task differently. The Smart behavior of true slime mold is written in colloquial terms and may be easier to read for someone who is not scientifically oriented. The use of the first person 'we' , and how a question was asked open-endedly 'What sort of behavior could be expected?' are examples. This style is not very common in scientific writing and not present in the Monophagous leaf‐mining article. The Monophagous leaf‐mining article uses passive voice and no first person. It stays focused on the facts. However, this is not to say that the final product of one or the other doesn't achieve what it set out to do. 

Both articles use a level 1 header and some text before the introduction in order to give background information on the study. Both articles have sub-sections and use level 2 headers for their sub-sections. In the Smart behavior of true slime mold article, the subsections give a basic description of what the section will be on, almost like a topic sentence. The Monophagous leaf‐mining article uses a scientific subsection style consisting of an introduction, methods, etc. Both achieve a similar premise of describing what the following section is about by different means. The subsections in Smart behavior of true slime mold usually begin with introductory sentences which give the reader a basic overview of what will be discussed, while the Monophagous leaf‐mining sections immediately introduce the content and skip the 'fluffy' introductory sentences. In both articles, the subsections are used to introduce the new content to continue the flow of the paper. They both follow logical schemes which lead the reader to a final conclusion.


Submitted by mlabib on Thu, 09/12/2019 - 22:28

My draft today is something I have always been curious about and would like to know more about. SSRI's, which stands for Selective Seratonin Reuptake Inhibitor. I have been on these for almost a year yet I do not exactly know what they do inside our body. They ease depression by increasing levels of seratonin in the brain, which is usally what people taking this medication need. Seratonin helps you feel happy, and if you have too little of it, you will feel down. Since information is communicated between brain cells, there needs to be a connector, which is a neurotransmitter. Seratonin is a neurotransmitter. It has a neuron called seratonergic neuron. As seratonin releases, it gets released into the synapse. Then, it can either keep going through the post synaptic neuron, or get reuptaked. When enough seratonin goes through the post synaptic neuron, you can finally feel happy. However, if you are depressed, not enough seratonin will go through. So, SSRI's will travel through the pre synaptic neuron, and will block the seratonin from going back up. That leads to a buildup of seratonin in the synapse, and when the body detects it needs seratonin, there will be seratonin available in the synapse to go through the post synaptic neuron. This is a very interesting finding for me, as I never really discovered the true function of SSRI's. I believe this is the best kind of antidepression to prescribe to patients, as there is a guarantee that the seratonin will not go through the reuptake channels. This can be tricky though however, because the body will always want more, which is why individuals tend to increase their dosage after being on a certain dose for 4-8 weeks. They are also called selective as they work only with the seratonergic neuron, and not with other neurotransmitters. They do have side effects, but these side effects are not proven to be from the medication itself, and rather could be coming from the history of the patient.

Structure of scientific Literature

Submitted by mpetracchi on Thu, 09/12/2019 - 22:23

The scientific articles Smart behavior of true slime mold in a labyrinth and Monophagous leaf‐mining larvae of Stigmella (Lepidoptera: Nepticulidae) on birch: patterns and differentiation in exploitation of the host have many similarities and difference in their written styles. Both articles use a level 1 header and have some text before the introduction which give background information on the study. Both of the articles use level 2 headers for their sub-sections and both articles have sub-sections. These subsections explain what the following section will be about. In the Smart behavior of true slime mold article, the subsections give a basic description of what the section will be on. The Monophagous leaf‐mining article uses a traditional sub-section style consisting of an introduction, methods, etc. Both achieve a similar premise of describing what the following section is about. The sections in Smart behavior of true slime mold usually begin with an introductory sentence which gives the reader a basic overview of what will be discussed, while the Monophagous leaf‐mining article begins each section by jumping straight into the content and skipping the 'fluff'. In both articles, the sub-sections are used to introduce the new content to continue the flow of the paper. Again They both contain figures and descriptions of those figures. At the end of the articles, both papers have a reference section written in a similar fashion in alphabetical order. The way the informative paragraphs are written, in the introduction, are similar as well. Both articles begin fairly broad in the beginning and give basic information that leads the reader toward a more in-depth understanding of the subject and what the article is ultimately about. However, each article approaches this task differently. The Smart behavior of true slime mold is written in more colloquial terms and is easier to read for someone who may not be very scientifically oriented. Examples of this are the uses of the first person 'we' and how a question was asked open-endedly 'What sort of behavior could be expected?'. This style is not very common in scientific writing and not present in the Monophagous leaf‐mining article. However, this is not to say that the final product of one or the other doesn't achieve what it set out to do. They both follow logical flow schemes which lead the reader to a conclusion and are organized in their own ways from broad to precise. The Monophagous leaf‐mining article does this in a writing style many consider proper scientific writing.

mutations of sickle cell anemia

Submitted by ziweiwang on Thu, 09/12/2019 - 22:05

All of the mutations for sickle cell disease happens at 14p15.4. (OMIM). However, there are different types of mutation that can occur in the same place, and as a result, have similar effects. For example, the most common mutation is 141900.0243. This mutation causes the HBs variant of sickle cell disease, which is common in people who have traditionally lived in a tropical climate. Another variant is the HBc disease, which occurs in children. There have also been other mutations described, such as sickle cell (SE) disease, SC(Arab) disease, and SC (Harlem) disease which all have their own mutations.


    There is a clear genotype/phenotype association. The location that the mutation occurs is essential to the hemoglobin structure, and as a result, any mutation that happens in that part of the gene is likely to have the phenotype of sickle cell disease, although there are some variants of the disease that may be different. 


There are many factors that increase and decrease the severity. For genetic modifiers, having a Bantu/CAR type or Benin type of the modifiers is more likely to have more severe symptoms and more likely to be hospitalized. This is the same with low levels of Hbf, which can mitigate the effect of HBs. a high number of alpha-globin genes is also likely to make the disease worse. Higher wind speed, humidity, and pollution such as PM are also more likely to cause the disease to be worse. In addition, a problem with access to health care is also likely to cause the disease to worsen.

Running and Appointment

Submitted by nskinner on Thu, 09/12/2019 - 21:44

As a veterinary technician one of my many jobs in the hospital is to run appointments alongside a doctor. The very first thing that I do each day is go through the entire schedule and review what each pet is coming in for and make sure that their medical record matches their appointment notes for that day. For example, if a dog has an appointment for a wellness exam and a rabies vaccine, I want to ensure that the dog is actually due for a rabies vaccine. When the client checks in for the appointment, I then walk to the reception area, obtain a clip board that has a check-in sheet on it and call out the name of the patient that is here for the appointment. I then bring the client and the pet into the exam room. I always introduce myself as “Nikki, one of the technicians here” so the owner of the pet knows who I am and what my roll is in the hospital. I then begin by confirming the patient is there for the correct thing. If the pet is there for a wellness appointment I may say “I see you’re here with your pet to get a wellness exam and up to date on vaccines.” If the owner confirms this is correct, I then ask a very open-ended question “How is (lets say fluffy) doing today? Any concerns?” This opens the floor for the owner to tell me about anything they can think of that may be of concern to them. Sometimes concerns can include that their pet has been itching a lot lately. Sometimes the owner states they have no concerns at all. I then ask a slew of detailed questions as I am searching for very particular information about the pets well being that the owner may have forgotten to mention, or possibly they didn’t realize could be a negative aspect to their pet’s health. I ask if their pet has had any coughing, sneezing, vomiting, or diarrhea. I also as if their pet has any increase in drinking or urination. I will also ask how their pet’s energy, activity and behavior has been. I want to know what their pet eats and how much. I also ask if their pet goes to boarding facilities or daycares or any other place where they are exposed to other animals. While I am asking these questions, I will be watching and accessing the pet’s behavior. A dog that is fearful may sit quietly. They may be panting, or lip smacking, which is basically licking their lips. Many people do not know that lip smacking is a sign of anxiety for dogs. Some dogs are happy to be there jumping up on me wagging their tail. Cats generally are sitting quiet with their legs tucked in underneath themselves. Their tail may be twitching at the end. Cats like that are generally not happy and possibly anxious, fearful, or stressed. Cats that are lounging around with their legs out or walking around bunting items in the exam room are comfortable and not afraid to be there. After asking questions and documenting them in the medical record I weigh the patient and record their weight. I then exit the exam room to round the doctor on how the pet is doing, what they are due for, and what the owner would like to have done. I will then draw up vaccines and get their invoice for the visit all set in the software system that we use. I enter the room with the doctor and restrain the pet for the physical exam and vaccines. If they pet is do for lab work I will then take the pet to the treatment area in our hospital while the owner discuses any questions or significant findings during the pets physical exam. I will draw blood, collect urine if needed, trim nails, then bring the pet back to the exam room. At this point the owner is usually finishing up talking to the doctor and will be heading to the reception area to then check out for their appointment. Of course, not all appointments run like this because not all appointments are just wellness visits for vaccines. Some appointments may include giving injectable medications, subcutaneous fluids, or even in extreme cases life saving procedures such as CPR.  

Sleep study

Submitted by ekirchner on Thu, 09/12/2019 - 21:19

When setting up a participant for a sleep study, there are 3 types of electrodes that must be properly placed. The first are EEG, electroencephalogram, which are placed around the head and measure brain activity. The second are EOG, electrooculography, which are placed on the sides of the eyes and measure rapid eye movements. The third are EMG, electromyography, which are placed in certain positions on the face. The participant wears an embletta unit that all electrodes are plugged into, as well as two respiratory belts, one for the thorax and one for the abdomen. There is also a nasal cannula and thermistor that the particpant must wear that measure air flow and temperature, as well as EKG monitors for the heart and leg electrodes that will detect restless leg movements. Finally, once the participant's equipment is all set up and everything is working correctly, their head is wrapped with pre-wrap to make sure everything stays secure during the night. 


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