In my project, I constructed a particle detector in order to detect muons coming from cosmic rays. The detector was designed by MIT under the project called Cosmic Watch: Catch yourself a muon [1]. The assembly of the detector involved soldering various electronic components on the board circuits. In the end, I had a fully-assembled detector which was able to register events. While recording, the event rate was not constant and was not consistent with cosmic rays rates. Therefore, the detector needs further troubleshooting.
Electrical malfunctions are one of the leading causes of domestic fires in the United States. Between 2012 and 2016, electrical failures were responsible for 44,860 residential fires (Richard Campbell, "Home Electrical Fires"). All electrical circuits contain circuit breakers, which are used as safety mechanisms to interrupt current flow when a fault develops. It is not always possible to determine if an electrical fire resulted from a circuit breaker malfunction. Thus, it would be beneficial to have a cost-effective and user-friendly system that allows people to test the circuit breakers in their homes regardless of their technical background. The purpose of this capstone project is to develop a reliable and cost-effective automated system capable of testing multiple residential circuit breakers to determine their trip response in the event of a circuit fault. The automated system adopts the UL 489 test procedure fromUnderwriters Laboratories (UL) to test the circuit breakers. The system contains a computer-controlled power supply that outputs a variable current which generates enough heat to trigger the circuit breaker under test. Moreover, the system uses a solid-state bidirectional current controller known as a TRIAC to regulate the current delivered to the circuit breaker being tested. Overall, the automated system can be used to test new and currently installed circuit breakers to determine if they are capable of preventing electrical fires.
We examine at how hybrid images are created on a quantum computer. We wish to find how feasible it is to create a hybrid image, seeing if there are any difficulties in creating it. We start with a background of what hybrid images are and how a quantum computer works at a basic level. We then look at the possible image representations that are used, as well as different filtering algorithms to implement. An attempt is made to implement a filtering algorithm on a simulated quantum computer, but did not completely match the results of the earlier work.
https://prezi.com/view/m2LASWsobUH3adoNNszE/ With the rise in acceptance of LGBT rights, Western culture is slowly moving away from the idea that there are only two genders, male and female. While many people are still not accepting of non-binary identities, and the media likes to paint them as a new phenomenon, the reality is that third genders have been a respected and celebrated part of many non-Western and Indigenous cultures for centuries. The research for this project was done in two parts, with the first part looking into eight different third gender groups around the world: Muxes (Juchit√°n, Southern Mexico), Kathoey (Thailand), Hijra (India), Two-Spirit (Indigenous North America), Fa'afafine (Samoa), Waria (Indonesia), Calabai, Calalai, Bissu (South Sulawesi, Indonesia), and Mahu (Hawaii). The second part heard from non-binary students at Union College, about various topics such as their own identities, thoughts about current and future non-binary representation in the media, and what can be done to make Union College a more accepting place. The goal of this project is to educate people on and expose them to different ge
During the summer of 2019, Professor Francis Wilkin and I joined the Transiting Exoplanet Survey Satellite (TESS) Follow-up Program Working Grouptoanalyze planet candidates from NASA's TESS mission,launchedin 2017. The satellite views the sky in sectors for only 28 days per sector, requiring ground based follow-up observations to identify events on target or eliminate false positives. I have used the Union College Observatory in Schenectady, NY and El Sauce Observatory in Chile to obtain 21 observations during the duration of my thesis. Of these, 8 were submitted to the follow-up team in Sub-category 1, (seeing limited photometry). After Submitting my thesis, I have moved on to the Las Campanas Observatories(LCO) Key Data Group, as partof the follow-up team.
The field of printable electronics has been experiencing increased interest and growth to meet the demands of low-cost, flexible, and lightweight devices. From this subset of devices, graphene-based printable sensors are of specific interest due to their transparency, flexibility, biocompatibility, and high conductivity. In this research, a graphene-based ink is formulated and developed with the goal of having it exhibit characteristics that are suitable for a sensor, namely being electrically conductive, easily manufacturable, and printable through an inkjet-based printer. Based on the ink formulation methodologies presented in the journals Carbon and The Journal of Physical Chemistry Letters by Parvez et al. and Secor et al., respectively, a new graphene-based conductive ink formula and process was developed in this project. To develop this ink, a water-based graphene solution was prepared with a sonication process that demonstrated stable graphene suspension and dispersion in deionized water for up to one month. Additionally, the ink was characterized by a statistical sample of particle height and particle lateral size distributions; surface tension; density; viscosity as a function of shear rate; conductivity; and theoretical inkjet printability using a variety of scientific equipment and procedures. The final product was an ink that could be easily manufactured with simple lab equipment and exhibited a desirable set of liquid properties that represent the ability to be theoretically printed but failed to reach an experimental conductivity on the scale that was achieved in the Parvez et al. and Secor et al. studies.
The Vietnam War was a defining moment in the 20th century and reshaped the landscape of global politics.In my thesis, the post-war period (1975-2020) is analyzed, noting the remarkable changes in relations between the US and Vietnam, from bitter enemies in a traumatizing and lengthy war to a process of reconciliation and normalization. During this period, Vietnam transforms from an isolated, repressive, and poverty-stricken communistnation to a dynamic economic actor with a more complicated political and economic system. The crucial shift occurred in 1986, with the doi moi reforms. At the same time, the US position toward Vietnam was also shifting, from bitterness and anger toward its defeat and concern about POW'sand MIA's, to a grappling with US responsibility toward Vietnam (as Agent Orange and various massacres), as well as concern about the geopolitical realities in Southeast Asia, and that US long-term interests require a more measured relationship with Vietnam as the US attempts to balance the growing power of China. I examine these issues at various levels, most importantly, through the career and shifting views of John McCain.McCain began as a committed military man, patriot, who was captured by the North Vietnamese, and harshly treated in a long captivity. And yet, after his release, and after becoming a powerful Senator in Congress, McCain led the way toward a changed relationship with Vietnam, from both a ethical and national interest perspective. While other Americans were fiercely divided on such issues, McCain courageously argued over the years for a step-by-step normalization policy. I also examine others individuals and groups that articulate various positions on this difficult issue that has continue to adapt to new circumstances over these last 35 years.I concludeby examining thecurrent implications ofcontinued normalization of relations with Vietnam in a world defined by the ongoing competition between the US and China. Even today Vietnam provokes strong feelings and debate, as the deep and nagging wounds inflicted upon one anotherbegin to wane as the years go by.
Follicle Stimulating Hormone, or FSH, is a critical hormone involved in reproduction. In men, FSH signaling in Sertoli cells triggers spermatogenesis, and in women, FSH signaling in the granulosa cells is responsible for follicular development. Current hormonal contraceptives have been found to have incredibly high effectiveness but can also carry multiple side effects. In addition, their effectiveness can be altered due to an individual’s FSH, estrogen, progesterone , or GnRH levels. All FSH signaling happens through the FSH receptor, a member of the G-protein Coupled Receptor (GPCR) family. This receptor is known to interact with many other proteins along its complicated signaling pathway, and there are still many more associated proteins yet to be discovered. Using the APEX technique, the proteins proximal to the FSH receptor were labelled and purified. In the future, these proteins could be analyzed using HPLC-MS, and identified using various computer software. Small proximal proteins, like those isolated in this study, have been shown to allow for receptor activation and function modulation. Thus, this study opens the doors for much more work in the field of contraceptives for both men and women. Another potential benefit from identifying FSHR associated proteins would be in developing new approaches for In Vitro Fertilization (IVF). To perform IVF, FSH is given to women to cause rapid follicle stimulation and maturation. This produces multiple ovulation events and allows for a higher chance of pregnancy. The problem, however, is that FSH alone is expensive, and the chance of multiple pregnancies is vastly increased. Targeting the pathways downstream of the FSH receptor could allow for more careful modulation of the follicle growth and could be much less expensive, vastly lowering the cost of IVF and making it a more viable option for those seeking infertility treatment.
This research paper aims to analyze the current US-China relationship in order to better understand whether China's rise to power will be achieved through military engagement or if it will come about in a peaceful manner. This paper argues that a multipolar world order is plausible, but what remains uncertain is the dynamics and future implications of these changes for global governance. Power transition and Institutional theory, along with Graham Alison's Thucydides Trap analysis, are highlighted to demonstrate the different schools of thought on the outcome of the US-China rivalry. Graham and Power transition theorists remain skeptical of a peaceful rise of China while Institutional theorists are more confident of the role international institutions will play in mediating conflict. Current events like disputes in the South China Sea, independence of Taiwan, role of multinational organizations and access to nuclear weapons are then analyzed through the lenses of these schools of thought. The paper emphasizes the possibility of military hostility between nations involved in the South China Sea dispute, because some of these nations are US allies, the US may engage in such a war with China in the region. Similarly if the Chinese desire for greater voting powers in current international institutions is not met, China may engage in creating alternative multinational organizations where it has greater influence, like the New Development Bank and Asian Infrastructure Investment Bank. This will considerably undermine institutional theorists' claim that international institutions will be successful in preventing conflicts from escalating into war. The paper also discusses the role nuclear weapons play in deterring war. The difference in both nations' nuclear policy induces a competition between these countries to increase their nuclear capabilities, unlike the MAD doctrine adopted during the cold war.
Kirschner Pins, known as K-wires, are smooth sharp stainless steel pins used in the field of orthopedics to stabilize bone fracture fragments in their correct position until they have fully healed. K-wires are most commonly used for comminuted metaphyseal fractures of the long bones, and fractures of smaller bones such as the phalanges. The wires are inserted into bone via a drill and the ends of the wire are bent and left outside of the body for easy removal once the bone has healed. The surgeon uses x-ray images to guide K-wire insertion, ensure proper internal alignment, and determine if any adjustments need to be made. The identical and 2D appearance of the K-wires on x-ray images presents orthopedic surgeons with a challenge of identifying, within the surgical site, the correct K-wires to adjust during surgery. This leads to unnecessary radiation exposure for the patient and longer procedures. We are designing a K-wire attachment to be used by the surgeon that gives each K-wire a unique appearance on the x-ray so that each wire can be identified from different imaging angles. Overall our device will decrease the number of x-rays that need to be taken during surgery, thereby increasing the safety and efficiency of bone reconstruction surgeries. By creating a temporary attachment to be applied by the surgeon, both the number of x-rays and amount of time in surgery will be decreased.
Nymphettamine is a nonlinear creative narrative that combines poetry and prose to explore psychosis, grief, trauma, addiction, psychiatric asylum, and the healing properties of art and nature. This series of vignettes exists between the realms of fiction and nonfiction to translate the disorientation of navigating the dual realities that are characteristic of a manic episode to the reader. Nymphettamine is equal parts memoir, fictive depiction, and thought experiment, which, as a whole, becomes an echo of the processes that occur when one experiences psychosis. Told in scattered images to emulate intrusive thoughts, obtrusive hallucinations, shifting night terrors, and Rorschachian inkblots, Nymphettamine is carried by seemingly dissonant voices; spirits linked by ephemeral connecting threads mirroring the nature of the "looseness of associations" that informs the perceptions of psychotic individuals. This project was driven by a desire to explore queer identities, their relationships with psychiatric institutions, and the fictive visibility, or lack thereof, of individuals diagnosed with various psychiatric disorders. Nymphettamine attempts to confront and subvert archetypical characteristics of mentally ill women by delving into the infinite complexities of each character. The women in this collection are not defined by their psychiatric diagnoses, instead, they are characterized by the way that they interact with moments of dysfunction or function. They embark upon a lifelong pursuit of fulfillment, balance, and artistic creation while they rebel against the archaic psychiatric authorities that attempt to subdue or silence them. Instead of falling prey to the literary tropes of suicide or debilitating incompetence caused by "hysteria" that have been used for centuries to cut the fables of "madwomen" short, reducing their existence to cautionary tales or dramaticized plot twists, each woman outlives their psychotic breaks, sexual assaults, unpredictable erraticisms, and debilitating substance dependencies. Their lives are left ambiguous, given to the reader only in selective, vibrant, slivered glimpses that allow each woman to continue on even after the collection's closing. Thus, they become ethereal victors to pay homage to the strength--presented in opposition to the weakness of the dismantled mind outlined by both fictive and psychiatric texts--required to overcome the severity and the longevity of each psychotic disorder.
I report on a photometric analysis of three cataclysmic variables (HP Lib, NY Lup, and NR TrA) that we observed using the 0.6m-telescope in El Sauce Observatory in Chile and the 0.43m-telescope in Siding Spring Observatory in Australia from June 2020 to March 2021. We used 45s exposures and a 2 to 3 hour-long span. Our goal is to produce a light curve for each target star in order to observe the variation over the course of the observing period. Analyzing the light curve allows us to determine properties of the binary system, such as variations in the material flow rate between the two stars. For our analysis, we used the image processing software AstroImageJ to align our image ensembles and we chose from several field stars for our comparison and check stars for our targets. After performing a photometric analysis of our data with the same software, we observed a substantial variation in the light of each target for each night. Our data will be contributed to the data bases of the Center for Backyard Astrophysics, an amateur professional collaboration, and of the American Association of Variable Star Observers.
Analysis of Possible Hybrid Meson Decay - Jasper Bergh This research looked at data from the GlueX experiment at the Thomas Jefferson National Accelerator Facility to search for evidence of the π1(1600) particle, an exotic hybrid meson, decaying to an eta' and π0. We specifically looked into decays of the eta' to an eta, π+, and π-, with the eta decaying to 3 πo's. We successfully reconstructed an eta from the 3 πo's, and an eta' from the eta, π+, and π-. However, we did not observe the π1(1600), but, a 6:1 ratio of signal to background in the eta' mass. With more statistics this would be a viable channel to search for hybrid mesons. PIXE Analysis of Soil Samples Near the George Washington Bridge - Helen Black Heavy metal pollution is being investigated near bridges in New York City as part of an ongoing environmental pollution project at Union College. Soils collected from around the George Washington Bridge, that crosses the Hudson River, between Washington Heights in Manhattan and northern New Jersey, were investigated for the presence of heavy metal pollution using Proton Induced X-Ray Emission (PIXE) Spectroscopy. 2.2 MeV proton beams were generated in the Union College Ion-Beam Analysis Laboratory and used to bombard 21, 1-g soil pellet targets. The collected soils were sifted and pressed into targets with 10 pellets prepared from the NY side and 11 pellets prepared from the NJ side. X-ray energy spectra were generated and the results of the PIXE analysis show considerable amounts of lead present in the soil at the base of the George Washington Bridge. The lead concentration tends to decrease as the distance from the bridge increases, and this trend is present on both sides of the bridge. The highest lead concentrations were determined to be directly under the span of the bridge with 1509 +/-253 ppm seen on the New York side of the bridge and 478 +/-108 ppm on the New Jersey side of the bridge. Electron Positron Annihilation Lifetime Spectroscopy - Jacob Feinstein This poster presents an introduction to module theory,the purpose of which is to bring an advanced undergraduate student of mathematics to a level of understanding of modules and of tensor products.The thesis on which this poster is based was inspired by various resources written on each topic of interest and was written with the purpose of exploring the tensor product and some of its implications through the lens of introductory module theory. The goal of this poster isto provide a concise and clear introduction to modules and their properties, tensor products, and the dual space of a vector space. Dimensional Reduction on a Scalar Field - Daniel Resnick The introduction of a compact extra dimension into a scalar field theory introduces an infinite tower of increasing (3+1) dimensional masses, called a Kaluza-Klein tower. This process, known as "dimensional reduction,'' depends on the curvature of space-time. We present a very brief overview of the framework necessary to perform a dimensional reduction and an analysis of a trivially curved (4+1) dimensional space-time, followed by a brief discussion on more general curvature and its effects on a Kaluza-Klein tower.
Music production has a high bar of entry due to a multitude of reasons. This can be not only because of the expensive cost of hardware and software but also due to the immense amount of musical knowledge required across an array of disciplines, not limited to simply playing an instrument. In addition to the knowledge required simply to do this on paper, the difficulties are further exacerbated when adding the challenge of understanding current software solutions which often times have a high learning curve. As a revisitation of the initiative last year lead by Ian Krause & Raphael Sebastian II, the goal of this project is to design and implement a software system capable of transcribing music in real time. More generally, the purpose of this endeavor is to make the goal of independent music production easier and more assessable than it has ever been before to attain. With many of the individual pieces of the problem on their own solved, one strategy that has been carried throughout development of this project has been embracing open source implementations. With this, various libraries that pertained to different parts of this project have been found from utilizing signal processing techniques for assigning frequencies to notes, or parsing music notation files. This proved to be a success as currently, the software is effective in identifying various musical notes from audio as well as being capable writing them to the popular digital notation format MIDI which can then through various means be transposed to sheet music. While the current implementation has achieved much in what was aimed for, there is still much more to go from here. From a more verbose notation format to a more approachable user interface, this project has no shortage of possibilities with many of them being explored for the future.
During motor vehicle travel it is a near-universal practice to transport infants in a rear-facing car seat, formally known as a child restraint system (CRS). Car seats are subject to heavy regulations, extensive testing, and are safe, secure, and familiar environments for infants. The use of a CRS reduces fatalities associated with motor vehicle collisions by up to 71%. Current devices on the market for pre-hospital infant transport are harness-based and do not utilize these car seats. Aversion to use of these harnesses occurs for a variety of reasons. The device becomes visually unattractive after remaining in storage for long periods of time between uses. As a result, parents instinctually resist allowing emergency medical technicians (EMTs) to secure their children in these harnesses. Our product will fulfill the need for a universal device that can secure an infant in a rear-facing CRS to an ambulance's cot. It will work with the brands of stretchers commonly used within the Capital Region and take up minimal space in the passenger compartment of the ambulance. Additionally, the product will meet federal guidelines associated with CRS use and be intuitive for EMTs to implement correctly. Facilitating the use of the child's own car seat during transport will allow for the continued utilization of a familiar, safe environment.
A conjecture made in 1849 by French mathematician Alphonse de Polignac is that every odd number can be written as a power of 2 plus some odd prime. Although easily seen to be false with counterexamples 127 and 509 it was not so easily discarded and caused some further thought and discussion on the subject. In 1950 Hungarian mathematician Paul Erdős introduced and developed the theory behind covering systems and proved that there are in fact infinitely many counterexamples to this conjecture of Polignac. In more recent years mathematicians have used covering systems to look at variations of the Polignac conjecture, some involving the Fibonacci numbers and the interesting properties they have as a whole. In this talk we will explore some of these variations.
This oral presentation is on my three weeks spent in Fiji completing the Klemm Fellowship on Nutrition and Chronic Diseases. Chronic disease is the primary cause of death in Fiji; about 80% of Fijians die of chronic diseases each year. My internship experience included conducting free health screenings in Native and Indo-Fijian villages, teaching health education at Dratabu summer school, and giving Zumba lessons at the community center for adults (including social workers, airport staff, and police officers). In addition, my team and I sought to bring social change in Nadi by spreading motivation and positivity during the intense dry heat period. We conducted a project in which we surprised strangers at the local market with inspirational quotes, and I designed a free personal food diary for patients to track their own health. My time in Fiji was also filled with Fijian language classes, hiking, traveling to the beautiful islands and beaches, and spending quality time with my loving host family.
The Albany Pine Bush Preserve, APBP, maintains a globally unique inland pine barrens ecosystem that houses many rare and endangered species. However, non-native black locust trees have invaded many pine barren sites, leading to a loss of biodiversity. The APBP commission staff have restored several of the invaded sites by removing black locust trees, replanting native vegetation, and introducing prescribed fire treatments. The restored areas have yet to match the original pine barrens habitat in plant species composition, but have a similar grassy, open habitat. The effects of restoration on local bee populations is unclear. The bee communities are extremely important to monitor as they are declining worldwide at an alarming rate. Bee decline is due to a variety of reasons including: habitat loss, pesticide use, and climate change. To analyze the bee communities in restored and native sites, four survey plots of each were established. We utilized pan trapping and sweep netting methods six times between mid-June and late September resulting in 958 individuals, which are being identified and prepared for quantitative community analysis. Bee communities in the two habitat types will be analyzed by comparing species abundances and diversity indices. In addition, community composition will be evaluated using non-metric multidimensional scaling to summarize species distributions among sites. We have already analyzed the differences in the number of bees collected at each site and there was not a significant difference between the number of bees collected at restored sites versus native sites (p=0.62). However, finding distinct bee community compositions between different site types has been a common result in other studies. We hypothesize that we will find similar differences in community composition between native and restored sites due to greater number and abundance of specialist bees in the native habitats.
The turn of the 21st century marked the beginning of a modern age in human history. As developing nations continued on their paths to industrialization, global markets became inter-connected, and large swaths of the people were lifted out of poverty throughout the world. As market demand increased due to the influx of new capital, new alliances between nations were drawn and the production of goods transformed. Today, firms are more globally fragmented than ever before. Rarely do firms house all facets of production in one location and serve only one market; instead, production is separated to cheapen product cost and maximize efficiency. Though this practice is beneficial for the firms involved, it simultaneously complicates how nation's control markets and protect domestic industries. It is necessary for governments to properly determine firm nationality if they are to govern and regulate appropriately. Recently, US-China relations were stressed as President Trump's "America First" protectionist trade policies clashed with China's attempts to become more self-sufficient. As the nations battled back and forth through a trade war, firms were caught in the middle, awaiting determinations of their fate which was decided based upon their perceived nationality. Accuracy in this process was crucial to limit the damage to markets that sanctions and tariffs would bring; there was little room for error. The conflict between the United States government, ARM Ltd. (ARM), and Chinese telecommunications giant Huawei is one such example that demonstrates the complexities of defining firm nationality. In May of 2019, the US government alleged that Huawei was a national security risk. Huawei repeatedly denied the allegations, but the United States enforced sanctions, all but banning American companies from doing business with Huawei. This situation complicated Huawei's relationships with its suppliers, one of them being ARM. Given that ARM believed some of its technology had originated in the United States, its leadership made the decision that the company fell within the extraterritoriality of US law and thus, that their firm was subject to adhering to the ban on selling technology to Huawei. Without ARM's designs, Huawei's production of processors came to a halt, and the firm was pushed to the brink of disaster. Nearly five months later, ARM's leadership reversed its decision and continued its sale of IP to Huawei when it determined that the technology in its designs was, in fact, from the UK. As can be seen from this dilemma, firm nationality can have real, potentially crippling implications for firms and broader market structures. Defining firm nationality is not just an academic exercise; rather, it has relevant policy implications. No matter the stances that the United States and China take going forward, it will be of vital importance that decisions are made while accurately considering firms' nationality
In Sub-Saharan Africa, 1 in 5 children are admitted to the hospital due to below average levels of oxygen in the blood caused by respiratory illnesses such as pneumonia. Other acute lower respiratory infections account for 1.4 million deaths annually in low resource areas. Pulse oximetry is commonly used to measure oxygen saturation levels, specifically for those with compromised respiratory conditions, to make sure that enough oxygen is being transported to the extremities. Low resource countries face many challenges to access pulse oximeters, mainly due to cost and durability of the device. This lack of oximeters decreases the ability to properly monitor newborns thus putting them at risk for further complications or even death. If a pulse oximeter is available, problems can arise from poor placement of the device resulting in inaccurate level readings. At Baby Ox, our proposed design of an improved attachment system for a pediatric pulse oximeter will result in more accurate oxygen level readings in addition to increasing the availability for low resource areas with its reasonable price.
Semantic representations of words can be acquired by both textual and perceptual information. Multimodal models integrate this information, and outperform text-only semantic representations of words. In many contexts, they better reflect human concept acquisition. A common model for semantic representation is the semantic vector, a list of decimal numbers representing the clusters in which a word appears in text. Studies have shown that if two words have similar vectors, they are likely to have similar meaning, or at least be relevant to each other. Other approaches entail inserting sentences, made up of caption words from an image set, into text, to modify the vectors corresponding to each word in a textual corpus's vocabulary, and thus form different semantic representations. These techniques have also suggested that whereas concrete terms' meanings tend to improve with propagation, abstract terms tend to become less accurate when too much information from their more concrete counterparts is propagated to them. In this study, I have therefore utilized different techniques for comparing words' meanings, to implement an image retrieval system. Even if a word w does not directly tag an image, the system retrieves images whose captions contain words that have the most similar vector representations to that of w. Therefore, we examine the extent to which a word's semantic representation has improved, based on improvements in corresponding retrieval results from this system.
To date there is no scientific evidence that dragonflies (Odonata), have a nervous system equipped to process auditory stimuli. Even with considerable research on these creatures due to their specialized vision and flight mechanics, there is no evidence that dragonflies have ears or even auditory neurons. Last year student Andrew Hamlin and Professor Robert Olberg recorded neuronal responses in the dragonfly to auditory stimuli of 100-2000Hz sounds (Olberg and Hamlin, unpublished). This year our research was aimed at understanding a sensory modality that was previously unknown in dragonflies, the sense of hearing. In order to investigate this question we used behavioral and electrophysiological studies on the live dragonflies Anax junius and Aeshna constricta. Behaviorally, dragonflies were loosely tethered to a standing mount allowing free movement while computer-generated sound stimuli were played to the animal and video-recorded. Electrophysiological studies were done by extracellular recording of the ventral nerve cord to observe neuronal activity in response to these computer-generated frequencies (50Hz – 22KHz). Due to the electrical and mechanical properties of a speaker, low range frequencies (100-200Hz) were used to conduct sound waves that directly contacted the dragonfly (near-field sound) while staying out of the electrical field of the speaker itself. This inhibited the electrical field of the speaker from being picked up in the extracellular recordings. We observed body movements to near-field sound waves in behavioral studies that backed up the initial observations. Our electrophysiological studies showed that sound waves do not stimulate an auditory sense through a tympanum but apparently stimulate mechanoreceptors on the body. This mechanoreception is subtle and highly dependent on the quality of the recording but does exist. Our findings suggest that the behavioral responses of dragonflies to loud sounds may be mediated by mechanoreceptors, such as sensory hairs, distributed across the body of the dragonfly.
