Welcome to UC Riverside's Undergraduate Research Journal
Volume 12, Issue 1, 2018
A Subset of Brain Neurons Controls a Sexually Dimorphic Proboscis Holding Behavior in Adult Drosophilia Melanogaster
Taste is essential for humans and animals alike to evaluate food quality and make important decisionsabout food choice and intake. How complex brains process sensory information to produce behavioris an essential question in the field of sensory neurobiology. Currently, little is known about tastecircuits in the brain as compared to other sensory systems. Here, we used the common vinegar fly,Drosophila melanogaster, to explore the potential role of brain neurons labeled by a transgenic line(VT041723-GAL4) in producing “proboscis holding” behavior (extrusion of the mouthpart withoutwithdrawal). By utilizing the GAL4/UAS binary expression system, we expressed a heat-activatedcation channel (UAS-dTrpA1) in these brain neurons and artificially activated them by elevationof temperature, subsequently examining behavior in the heat-activated proboscis extension reflex(PER) assay. We found that activation of these neurons induced proboscis holding. Interestingly, theproboscis holding phenotype was sexually dimorphic. Male flies rarely showed proboscis holdingand those that did had shorter proboscis holding durations. On the other hand, both mated and virginfemales showed significantly more proboscis holding and had longer proboscis holding durationsthan male flies. Overall, we identified a subset of brain neurons labeled by the VT041723-GAL4 linethat controls a sexually dimorphic feeding response (proboscis holding) upon activation.
The American Eugenics Archive defines race suicide as an alarmist term that describes, “when thebirth rate within a so-called race dropped below the death rate...with the ultimate consequence thatthe “race” would die out.”1 This article traces the ways in which fears and the concept of race suicide,a term coined by a sociologist committed to racial hierarchies, was reimagined by emerging blacksociologist, W.E.B. DuBois who actively sought liberation from systematic racism in the PostbellumEra. This historical research seeks to analyze the ways in which fear among communities of colormade claims of genocide inseparable from the histories of reproduction, birth control, sociology,race science, the Antebellum, and Jim Crow Era in the early twentieth-century. This is an attempt toprovide a speculative history that allows fears of those most vulnerable within systematic oppressionto be historicized, without the reigns of rigid, objectivity that act as a gatekeeper within the field ofhistory. I argue that tracing fears of race suicide allows for a complicated and necessary reimaginingof race science. The reimagining of race science allows us to see historical actors of color activelyengaging in liberation struggle through what Britt Rusert calls oppositional science. Similarly,analysis of race suicide allows us to bridge what Judith Butler calls, the theory-practice divide.
Surrealism, an art movement of the early twentieth century, was heavily influenced by psychoanalysis.The psychoanalytic theories that influenced Surrealism were based primarily on the research ofSigmund Freud. Freud’s research began with case studies on patients with hysteria, a predominantlyfemale diagnosed mental disorder. From his clinical observations of hysteria, Freud developedhis theories on unconscious drives and psychosexual development. André Breton, the leader ofthe Surrealist movement, first became acquainted with Freud’s ideas during the First World War.After his return to France from the war, Breton’s interest in avant-garde art and distaste for Europe’shigh culture led him to start the Surrealist movement. Breton declared psychoanalysis the basis ofSurrealism in the First Manifesto of Surrealism, believing that Freud’s ideas had the potential torevolutionize culture. For the Surrealists, adopting psychoanalysis as a doctrine of change resultedin a reinforcement of sexist stereotypes and discrimination against women that was rooted inFreud’s theories. While the Surrealist movement became notorious for being male dominated andmisogynistic, their idealization of Freud provided justification for their prejudiced beliefs. In thispaper, Salvador Dalí’s photo collage, The Phenomenon of Ecstasy, is analyzed to exemplify thetranslation of psychoanalytic ideas into sexualized and fantasy-like depictions of women in Surrealistartwork. The conducted research provides insight to the repercussions that Freud and psychoanalysishad on women in the Surrealist art community.
Social psychology has established a theoretical relationship between personality and academicperformance, but it has yet to identify the process by which personality influences real-worldoutcomes, such as grade point average. This paper proposes a model that explicates academicidentity’s role as a mediator in the relationship between the Big Five Factors of personality andcollege GPA. Specifically, the current paper focuses on the ability of personality to predict academicidentity. A college-going culture, or the extent to which a student’s high school cultivates a procollegeenvironment, is hypothesized to moderate the relationship between personality and academicidentity. To investigate the hypothesis, self-report measures related to personality and academicswere administered to 370 university students. Results generally supported the model, suggesting aprocess by which students’ personalities effect their academic attitudes. Educators are encouragedto foster college-going cultures which they can use to help students who are predisposed to adoptharmful academic identities.
Emotion regulation is the process through which a person changes his or her emotions. Individualsmay change their emotions in many ways, and these different aspects of emotion regulation mighthave different implications for one’s self-esteem. Self-esteem is defined as an individual’s conceptof the self. Despite the substantial research on these topics, there has been a lack of research onthe links between emotion regulation and self-esteem. The present study aimed to explore the linkbetween emotion regulation and self-esteem in young adults, as well as to examine potential genderdifferences in this association. Based on current research, we predicted that men would have higherself-esteem than women, whereas women would have a stronger capacity to regulate their emotions.Furthermore, we predicted women would show a stronger association between emotion regulationand self-esteem. Participants were asked to answer the Difficulties in Emotion Regulation (DERS)questionnaire as well as a singular measure to assess their self-esteem. The results of the presentstudy were consistent with our hypothesis that men would have a higher self-esteem, and that womenwould show a stronger association between emotion regulation and self-esteem. Our study adds to agrowing body of research on the importance of emotion regulation for self-esteem.
Parent Psychopathology and Parent-Child Conflict Interact to Predict Children’s Anxiety but Not Depression
Correlates of child psychology have been studied for decades (Ollendick & Herson, 1989). Researchhas shown that parental psychopathology can influence child psychopathology through a combinationof familial and environmental factors (Biedel & Turner, 1997; Burstein et al., 2010). Parent-childinteractions have also been found to relate to child psychopathology (Donenberg & Weisz, 1997). Apossible explanation for these relations is that the behavior of parents experiencing psychopathologysymptoms differs from parents not facing these difficulties, like displaying more hostile behaviortowards their offspring (Burstein et al., 2010). The present study examines the interaction of parentpsychopathology and parent-child conflict during a stressful task to see if conflict moderated therelation between parents’ and children’s psychopathology. We studied whether the relation betweenparent and child symptoms would be stronger for dyads characterized by conflict. 184 children aged3 to 11 (91 boys and 93 girls) visited the lab. Parents completed questionnaires to measure theirdepression and anxiety symptoms, as well as the child’s anxiety and depressive symptoms. Theparent and the child also participated in a Lego task where instances of child conflict were observed.Results showed that parent anxiety interacted with parent-child conflict to predict children’s anxietysymptoms, such that parents’ anxiety predicted children’s anxiety only among dyads characterizedby high levels of conflict. The same was not true for depressive symptoms. The current study expandsresearch about moderators by showing that the link between parent and child psychopathology isqualified by other aspects of the family environment.
Major Depressive Disorder (MDD) is characterized by the persistent presence of at least fivedepressive symptoms over a two-week period. These symptoms must include either depressedmood, or loss of interest or pleasure. Early identification, and ultimately treatment, of depressionmay be accomplished by identifying neural markers of individuals at risk for MDD, including thosewith subclinical depressive symptoms. Neuroimaging studies have shown that MDD is associatedwith impairments to integrity in white matter tracts such as the corpus callosum and internal capsule.However, it is unclear whether these same structures also are disrupted in subclinical depression. Thepresent study sought to examine this question through utilizing diffusion tensor imaging to assesswhite matter integrity as a function of Geriatric Depression Scale Short Form (GDS-SF) scores.Using a median split of GDS-SF scores, statistical analyses revealed no difference in white matterintegrity between low risk and high risk depression groups. However, there was a nonsignificant trend(p=0.072) such that higher GDS-SF scores were associated with decreased white matter integritylocalized to the corpus callosum, right internal capsule, left cingulum, external capsule and fornix.This finding extends previous research on MDD by providing evidence for similar neural correlatesof subclinical depression. This may provide insight into the development of MDD and ultimately aiddiagnostic and treatment efforts with early identification and intervention.
Parenting behaviors greatly influence children’s ability to regulate their emotions and handle stressfulsituations. Stressful life events can be particularly problematic for children as they are less able toeffectively manage these situations. Parenting behaviors that are warm and focus on directly helpingthe child handle negative emotions may serve as protective factors against the negative effects ofstress on children’s regulatory abilities. The aim of this study was to explore the role of parentalwarmth and parents’ emotion-focused reactions as moderators of the effect of stress on children’semotion regulation. A total of 184 children between the ages of three to eleven years old (M = 7.66,SD = 2.30) participated in this study. Parents reported on their child’s emotion regulation, exposure tostressful life events, and on how they, as parents, deal with their child’s negative emotions. Parentalwarmth was coded from an interactive task. Results showed that parental warmth moderated therelation between stress and child emotion regulation, such that children of highly warm parentshad better emotion regulation even when experiencing high stress. Parents’ reactions to theirchild’s negative emotions moderated the effects of parental warmth on child emotion regulation,such that parental warmth was particularly important for children of parents who place less focuson their child’s emotions when they experience a negative event. Our findings partially supportedour hypotheses and offer new insight into the importance of parental warmth as a protective factoragainst the negative consequences of stress on children’s emotional functioning.
The bioaccumulation of environmental toxins as possible risk factors in the etiology ofamyotrophic lateral sclerosis and parkinsonism-dementia complex (ALS/PDC) is studied inthree foci of the Western Pacific: Guam, the Kii Peninsula, and West Papua New Guinea. Theobjective of this study was to evaluate the best evidence on the exogenous causes of ALS/PDC, with emphasis on the role of cycads, iron, and manganese in the Western Pacific foci,by performing a systematic review of major electronic databases using predefined criteria, 68of which met the selection criteria. Two major environmental hypotheses are associated withthis enigmatic disease: the vegetal hypothesis, which focuses on the neurotoxic and genotoxicproperties of the cycad, and the mineral hypothesis, which focuses on the neurotoxic propertiesof metals. Although typically studied independently, environmental data suggests these twohypotheses may, in fact, converge. Epidemiologic research investigating the association betweenexposure to environmental toxins and ALS/PDC has proven inconclusive. Nevertheless,possible causal links indicate a need for more holistic research to not only better understandALS/PDC, but also glean new insights regarding the associated neurodegenerative diseases.
Working memory (WM) is engaged in most cognitive tasks deployed in the human brain. Braintrainingregimens that target WM may promote plasticity, leading to improved WM skills.Additionally, sleep is known to facilitate consolidation of newly learned information and skills. Here,we asked if napping could boost benefits of brain-training for WM. Participants completed ten days ofWM training on an N-back task; on each training day, a subset of participants were given a 30-minutenap opportunity (with EEG recording) immediately following their training session (training+nap).In Study 1 (n=10), we equated the amount of training (20-min training/day) in all participants andcompared training only to training+nap. In Study 2 (n=8), we asked if napping can effectively replaceadditional time spent training; we compared training+nap (20-min training/day) to double training(40-min training/day). On average, the nap group slept 16.0±5.77 minutes/nap in Study 1 and15.98±7.44 minutes/nap in Study 2. Our dependent measure of performance was the highest N-levelachieved on each day of training. In both studies, we found that performance improved across theten days of the study. However, there was no day x group interaction in either study, suggesting thatthe degree of improvement did not differ between training only vs. training+nap groups. In Study 2,there was a trend towards more improvement with double training compared to single training+nap.For people looking to dedicate time each day to improving their WM, it may be more beneficial tospend the entire time training rather than training+napping.
Children are exposed to many areas of interest and careers through accessible media and technologicaldevices. Research has shown that STEM careers are lacking in female representation. Accordingto the National Science Foundation, women only represented 28% of individuals in science andengineering occupations in 2010 (NSF 2014). Exposure to STEM careers in early childhood maybe an underlying cause of this underrepresentation; thus considering young children’s feelings andinterest in STEM is important for nurturing students to enter STEM fields. Children between ages3.61 to 7.21 years (N = 79) were asked about their interests in STEM activities and feelings abouta STEM task before and after playing a STEM application. Children reported decreased levels ofSTEM interest from pretest to posttest, whereas children’s self-efficacy for a STEM activity did notsignificantly differ from pretest to posttest. The results suggest that short-term exposure to a STEMapplication did not increase children’s STEM interest and self-efficacy toward STEM, as measuredby children’s verbal report.
Determination of Immune Signal–Receptors, PD-1 and PD-L1, Interactions in Solution using qFRET Technology
Human PD-L1 (programmed cell death 1 - ligand 1) is a transmembrane protein that is highlyexpressed on the membrane of cancer cells. It binds to inhibitory receptor PD-1 (programmed celldeath protein - 1), which is expressed on the surface of cytotoxic T cells. The interaction betweenPD-L1 and PD-1 reduces the effect of anti-tumor immune response and the strategy of blocking theirinteraction has been used for anti-cancer drug manufacture. Past studies isolated the extracellulardomain of PD-L1 for characterization of the structure. This study aims to recover, isolate, and purifythe insoluble PD-L1 protein (external domain), and study its binding interaction with PD-1 forthe development of an in vitro quantitative FRET (qFRET) assay. To report PD-L1/PD-1 bindinginteraction, fluorescent donor and acceptor pairs, CyPet and YPet were bound to PD-L1 and PD-1proteins respectively and qFRET was applied to assess the interaction of the two proteins basedentirely on fluorescence.The results provide evidence of recovery of the purified and refolded CyPet-Ext.PDL1 and YPet-Ext.PD1 proteins from cell pellets, shown in the coomassie stained SDS-PAGE gel. This study alsoshows that the proteins were able to be recovered through affinity chromatography under denaturingconditions. The qFRET technique showed that the acceptor, YPet-Ext.PD1, is interacting with thedonor, CyPet-Ext.PDL1. This study provides a novel method for better understanding the bindingmechanism of PD-L1/PD-1 that can be applied to other cell-surface protein interactions, as well as tostipulate a platform for small molecule inhibitor related drug screenings and production.
The Queer Confessional: Foregrounding the Discordant Poetics of Henri Cole Through the Troubling of Genre
This paper is a research study on a nascent American Poet, Henri Cole, whose scholarly archiveremains minimal, positioning itself as a fundamental starting point to which to begin a discussionaround a new, but critical voice within the field of American Poetics. The discordant poetics of HenriCole are informed by two distinct traditions within the canon of 20th and 21st century Americanpoetics, namely that of a queer and confessional mode to which he stands at the intersection ofboth movements. However, Cole’s scholarly archive is woefully small due to his recent publicationpresence in the literary field. Thus, research was focused on analyzing Cole’s chief poetic inspirations(Hart Crane and Elizabeth Bishop) as well as recursive forays into queerness and confessionalpoetics. In identifying that intersection, I argue that Cole is at the forefront of troubling poetic genrethrough the proposal of a ‘queer confessional’ mode of poetics. Cole troubles the notion of truththrough utilizing a queer perspective on the confessional genre that has historically fell to criticismsof histrionics and overt inwardness. Instead, this paper aims to subvert a long history of literarycriticism through instead focusing on how a queer confessional form ‘retrieves’ the confessional asa radical, poetic gesture that relishes in the instability of truth-making through a simultaneous reaffirmationof poetic genre. Cole thus disrupts and revises the notion of literary tradition through hisqueer perspective; in which his ‘queer confessional’ proposes a poetics of liberation.
Mice exhibit defensive behaviors in response to various predator cues. When a mouse “senses”a predator at a close distance, it exhibits freezing behavior. Alternatively, when it senses bodilyexcretions from a predator, it escapes from the area. These behaviors are evolutionary responses topredators that help their increase survival. How animals sense the different types of predator-derivedcues and induce appropriate behaviors in response to the specific predator cues have largely remainedelusive.In this study, we aimed to establish a method to analyze mouse behavioral responses toward variousforms of predator-derived biological samples, such as cat saliva, which contain chemical cues. Wecategorized mouse responses to predator cue exposure as freezing, fear assessment, or exploratorybehavior, each of which is triggered by different levels of fear that the animal is experiencing. Thebehaviors were quantified manually and compared between the animals exposed to control andpredator-cue stimuli. We show that this protocol is effective in analyzing levels of fear in mice asthere is a significant increase in the occurrence of fear-based behaviors in mice exposed to cat saliva.Developing a strong protocol for quantifying fear-related behaviors is essential to understand brainmechanisms underlying behavioral responses induced by different types of predator cues in mice.Moreover, the present protocol can be further utilized to understand how different levels of fear areprocessed in an animal’s brain circuitry.
Cyclin-dependent protein kinase regulatory subunit 1 (Cks1) is involved in cell cycle progressionthrough interactions with cyclin-dependent kinases (CDK) and ubiquitination of cyclin-dependentkinase inhibitors (CKI). Dysfunction of CDK dependent associations can affect the entrance of acell into mitosis, particularly the G1-S phase transition. Abnormal assistance from Cks1 with themultiprotein complex SCF (Skp2) in the ubiquitination of CDKN1B (p27Kip1) can disrupt the mitoticregulatory protein levels escalating to cancer development. In this study, we use computationalmethods to investigate interactions in three different complexes sharing Cks1 in order to create atargeted pharmaceutical solution that will assist in regulation. Our analysis is performed using thecrystal structure of Cks1 in three complexes to include involvement between one ubiquitin ligaseand two CDKs. The assessment is based on the intermolecular electrostatic interactions, such ashydrogen bonds and charge-charge interactions. We observe that charge and hydrogen bonding playsa significant role in the stability between Cks1 and adjacent proteins in each complex. Due to largebinding interfaces and varied distribution of charge across the main contact regions, we decided thata condensed pocket on Cks1 that interacts with phosphorylated p27Kip1 should be selected for furtherin-depth examination.