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Week 7

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  During the second week of July, Dr. Fritz's lab ran out of Ben’s squish prep buffer along with positive Culex species controls. Instead of PhD student Ben Gregory preparing more of these solutions for me, he thought it would be best to teach me how to make the buffer! The protocol to make more of these reagents requires proteinase and RNAase-free water that is communally shared in the lab. To use this water we had to pour the bottle high above an Eppendorf tube before using a graduated cylinder to avoid any contamination. Now that I know how to make squish prep buffer myself; I am better able to act independently in the lab. But there was another problem … without positive Culex restuans , and Cx. pipens controls, the PCR protocol could not identify the cryptic species! Therefore we had to do a protocol that Ben dreaded doing; DNA Extraction using the Qiagen DNeasy Blood & Tissue Kit. Just like the RNA extraction procedure I learned two weeks ago this procedure r

Week 6

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  The first week of July was  a short week  in terms of trapping. On Monday Ben, Izi, and I set up traps at the UMD Medical Campus Police Station, Queenstown Park, and the Patuxent Wildlife Refuge. The Patuxent Wildlife Refuge is the prettiest place we have set traps this trapping season by far! Now that it is July, we are going back through the 24 site locations to re-trap. As the summer progresses, the community distribution often changes resulting in different  species of Culex  peaking at  different  times. According to previous studies,  Culex  restuans  peak first near the end of spring, while  pipens  peak in June and July. 1 During the downtime of sorting and identifying Culex, Izi and I had the opportunity to learn more about other laboratory techniques of RNA isolation with an RNAeasy miniprep kit, along with qualifying controls used to determine the quantity of RNA isolated.   To start the RNA isolation process, β-Mercaptoethanol is mixed with Buffer RLT in a 2 ml flat-botto

Week 5

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 During the last week of June, my mentor Ben Gregory was out of the office for a vacation. As such, I have been tasked with catching up on the backlog of PCR and gel electrophoresis necessary to identify the difference between Cx .  restuans and Cx. pipens . Normally, during the week, I have performed two PCR’s per week; however, with six different trap nights coming in a week, and the preference to run smaller, 36 sample groups from each trap night, it has been challenging to keep up.  On Monday, Izi and I ran three PCR’s. Then I had to go set up traps at the last three sites of June; Hillcrest Park, SERC, and Church of the Holy City.  The Hillcrest Park gravid trap was set up between two trees next to a pond. The park happened to be windy, and I got dust in my eyes! On Tuesday, we ran more PCRs and got 100% amplification when viewing the gels. We also had to make more gels for gel electrophoresis on Wednesday. Here is the 100% amplification gel! I was so proud of the teamwork Izi and

Week 4

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  After nearly a month working at the Department of Entomology, I have got the hang of all the molecular work done to assist Ben with his research, including the most technical, polymerase chain reaction, otherwise known as PCR. PCR is a molecular technique used to amplify specific segments of DNA in vitro. Thermal cycling separates dsDNA into ssDNA and primers are used to select the DNA segment that will be amplified. In this case, multiple primers used to segment multiple target sequences to identify the different species within the Culex genus. The Primers are annealed to the template ssDNA to allow for the Taq, a DNA polymerase, to add onto the primers dNTPs to synthesize the segment of interest. This process of denaturation, annihilation and elongation repeats until billions of segments are replicated. Having a thorough understanding of the process of PCR provides a framework for how to set up a PCR in practice, as well as a great appreciation. The lab work of PCR is simple, unlik

Week 3

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During the third week, Izi and I learned about how to prepare a “squish prep” otherwise known as a DNA extraction. This step was fun to learn because it involves more technical squish prep where we must dissect the mosquitoes by separating the thorax from their abdomen.  Picture of dissected Culex mosquito. Abdomen is used for squish prep and kept in a strip tube while the thorax is kept in a separate tube as the individual. To prepare for this first part of DNA extraction, we set up an ice bucket to keep the thoraxes, and four strip tubes to keep the abdomen. The tubes for the thoraxes are much bigger and are labeled with the mosquito's names, which include the year, their trap night, and the number of the individual. We organize the individual abdomens using a drawn diagram. Shown below. This is an example of the notebook setup and the microscope used to dissect the mosquitos. the beaker contains a 10% bleach solution for disinfecting the Petri dish and forceps. Generally, it is

Week 2

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  After catching mosquitoes, the next step in the protocol is to sort mosquitos underneath a microscope. So to start off the second week of the internship, Ben showed me the proper way to identify different insects in the trap as well as the key field features of Culex mosquitoes! The first thing to look for to identify mosquitoes from other invertebrates are their scaly wings. They have hair-like appendages on the very ends of their wings. They also have a long proboscis, a long tubular mouthpiece used to suck up the blood of other animals. The insect above lacks scaly wings while the insect below is a Culex mosquito.  Culex in particular focuses on avians and people, though different subspecies have a preference for each group with Culex pipiens and Culex quinquefasciatus biting both humans and birds and people. The other species in the genus, Culex r estuans tends to feed primarily on birds. After identifying the insect to be a mosquito, the next field characteristic of Culex I w

Week 1

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Today was my first day of my internship! I was so excited to finally meet everyone I have been emailing for the past two months and obtain a better idea of the specifics of the project PhD student Ben Gregory has carried on with Dr. Fritz regarding the spatiotemporal organization of Culex mosquitos along an urbanization gradient. They have proposed that the relative abundance and distribution three West Nile virus vectors, Culex. pipens, Cx. restuans, and  Cx. quinquefasciatus have been influenced by the rise of new niches novel in cities driven by urbanization. This research can be applied to raise questions of current city design, and how urban areas might be contribute to the public health issue that is West Nile virus, and how might cities be designed or innovated in the future to reduce the opportunity for niches that promote these vector species habitation.   From a public health and epidemiological perspective I find this research to be fascinating, I had previously not conside