Near-Infrared Spectroscopic Measurement of the Effect of Leg Dominance on Muscle Oxygen Saturation During Cycling

The effect of leg dominance on the symmetry of the biomechanics during cycling remains uncertain -- asymmetries have been observed in kinematics and kinetics, while symmetries were found in muscle activation. No studies have yet investigated the symmetry of muscle metabolism during cycling. Near-infrared spectroscopy (NIRS) provides a non-invasive method to investigate the metabolic responses of specific muscles during cycling. PURPOSE: To determine whether there was an effect of leg dominance on thigh muscle oxygen saturation (SmO2) during incrementally loaded submaximal cycling using NIRS. METHODS: Eight right leg dominant, untrained subjects (5 men, 3 women; 31+/-2 yrs; 168.6+/-1.0 cm; 67.2+/-1.8 kg, mean +/- SE) volunteered to participate. Spectra were collected bilaterally from the vastus lateralis (VL) during supine rest and cycling. SmO2 was calculated using previously published methods. Subjects pedaled at 65 rpm while resistance to pedaling was increased in 0.5 kp increments from 0.5 kp every 3 min until the subject reached 80% of age-predicted maximal heart rate. SmO2 was averaged over 3 min for each completed stage. A two-way ANOVA was performed to test for leg differences. A priori contrasts were used to compare work levels to rest. RESULTS: VL SmO2 was not different between the dominant and non-dominant legs at rest and during exercise (p=0.57). How SmO2 changed with workload was also not different between legs (p=0.32). SmO2 at 0.5 kp (60.3+/-4.0, p=0.12) and 1.0 kp (59.5+/-4.0, p=0.10) was not different from rest (69.1+/-4.0). SmO2 at 1.5 kp (55.4 4.0, p=0.02), 2.0 kp (55.7+/-5.0, p=0.04), and 2.5 kp (43.4+/-7.9, p=0.01) was significantly lower than rest. CONCLUSION: VL SmO2 during cycling is not different between dominant and non-dominant legs and decreases with moderate workload in untrained cyclists. Assuming blood flow is directed equally to both legs, similar levels of oxygen extraction (as indicated by SmO2) suggests the metabolic load of cycling is not different between legs. This is in agreement with a recent study demonstrating symmetrical increase of muscle activation of the VL during cycling. Leg dominance did not influence VL SmO2 during submaximal cycling, but may have an effect at higher loads or during other forms of exercise, such as walking and running

Attitudes and Opinions About Direct-to-Consumer Genetic Testing in Undergraduate Science Students

Background: There has been exponential growth in the number of direct-to-consumer genetic testing kits sold in the past decade. Consumers utilize direct-to-consumer genetic tests for a number of reasons which include learning about one’s ancestry and potential ways to manage health. Emerging adults tend to be early adopters of new technologies; however, there has been little research regarding the opinions about direct-to-consumer genetic testing in emerging adults. Methods: Data came from a study conducted in an upper-level biology course focusing on understanding undergraduate science students’ overall experiences with receiving personalized genetic testing results from 23andMe. The present study used data collected at the baseline assessment which assessed their opinions and attitudes about direct-to-consumer genetic testing (N=133). Results: Over 80% of participants would recommend direct-to-consumer genetic testing options including carrier status reports, DNA ancestry reports, wellness reports, and trait reports to others. However, participants were not as confident that others would be able to accurately interpret their test results. Additionally, more than two-thirds of the participants stated that they would ask a healthcare provider to help interpret their personalized genetic test results. Conclusions: Participants lack confidence in both their ability to interpret their own results and others to interpret their results. It is important for direct-to-consumer genetic testing companies to educate consumers before providing results in order to minimize potential harms due to misinterpretation of results. Further research is needed to assess motivations to participate in direct-to-consumer genetic testing, impact of testing, and understanding of genetic testing results in emerging adults.https://scholarscompass.vcu.edu/gradposters/1124/thumbnail.jp

Tyramine and its \u3cem\u3eAmtyr1\u3c/em\u3e Receptor Modulate Attention in Honey Bees (\u3cem\u3eApis mellifera\u3c/em\u3e)

Animals must learn to ignore stimuli that are irrelevant to survival and attend to ones that enhance survival. When a stimulus regularly fails to be associated with an important consequence, subsequent excitatory learning about that stimulus can be delayed, which is a form of nonassociative conditioning called ‘latent inhibition’. Honey bees show latent inhibition toward an odor they have experienced without association with food reinforcement. Moreover, individual honey bees from the same colony differ in the degree to which they show latent inhibition, and these individual differences have a genetic basis. To investigate the mechanisms that underly individual differences in latent inhibition, we selected two honey bee lines for high and low latent inhibition, respectively. We crossed those lines and mapped a Quantitative Trait Locus for latent inhibition to a region of the genome that contains the tyramine receptor gene Amtyr1 [We use Amtyr1 to denote the gene and AmTYR1 the receptor throughout the text.]. We then show that disruption of Amtyr1 signaling either pharmacologically or through RNAi qualitatively changes the expression of latent inhibition but has little or slight effects on appetitive conditioning, and these results suggest that AmTYR1 modulates inhibitory processing in the CNS. Electrophysiological recordings from the brain during pharmacological blockade are consistent with a model that AmTYR1 indirectly regulates at inhibitory synapses in the CNS. Our results therefore identify a distinct Amtyr1-based modulatory pathway for this type of nonassociative learning, and we propose a model for how Amtyr1 acts as a gain control to modulate hebbian plasticity at defined synapses in the CNS. We have shown elsewhere how this modulation also underlies potentially adaptive intracolonial learning differences among individuals that benefit colony survival. Finally, our neural model suggests a mechanism for the broad pleiotropy this gene has on several different behaviors

Analysis of Hendra Virus Fusion Protein N-Terminal Transmembrane Residues

Hendra virus (HeV) is a zoonotic enveloped member of the family Paramyoxviridae. To successfully infect a host cell, HeV utilizes two surface glycoproteins: the attachment (G) protein to bind, and the trimeric fusion (F) protein to merge the viral envelope with the membrane of the host cell. The transmembrane (TM) region of HeV F has been shown to have roles in F protein stability and the overall trimeric association of F. Previously, alanine scanning mutagenesis has been performed on the C-terminal end of the protein, revealing the importance of β-branched residues in this region. Additionally, residues S490 and Y498 have been demonstrated to be important for F protein endocytosis, needed for the proteolytic processing of F required for fusion. To complete the analysis of the HeV F TM, we performed alanine scanning mutagenesis to explore the residues in the N-terminus of this region (residues 487–506). In addition to confirming the critical roles for S490 and Y498, we demonstrate that mutations at residues M491 and L492 alter F protein function, suggesting a role for these residues in the fusion process

Ehrlichia and Spotted Fever Group Rickettsiae Surveillance in Amblyomma americanum in Virginia Through Use of a Novel Six-Plex Real-Time PCR Assay

The population of the lone star tick Amblyomma americanum has expanded in North America over the last several decades. It is known to be an aggressive and nondiscriminatory biter and is by far the most common human-biting tick encountered in Virginia. Few studies of human pathogen prevalence in ticks have been conducted in our state since the mid-twentieth century. We developed a six-plex real-time PCR assay to detect three Ehrlichia species (E. chaffeensis, E. ewingii, and Panola Mountain Ehrlichia) and three spotted fever group Rickettsiae (SFGR; R. amblyommii, R. parkeri, and R. rickettsii) and used it to test A. americanum from around the state. Our studies revealed a presence of all three Ehrlichia species (0–24.5%) and a high prevalence (50–80%) of R. amblyommii, a presumptively nonpathogenic SFGR, in all regions surveyed. R. parkeri, previously only detected in Virginia’s Amblyomma maculatum ticks, was found in A. americanum in several surveyed areas within two regions having established A. maculatum populations. R. rickettsii was not found in any sample tested. Our study provides the first state-wide screening of A. americanum ticks in recent history and indicates that human exposure to R. amblyommii and to Ehrlichiae may be common. The high prevalence of R. amblyommii, serological cross-reactivity of all SFGR members, and the apparent rarity of R. rickettsii in human biting ticks across the eastern United States suggest that clinical cases of tick-borne disease, including ehrlichiosis, may be commonly misdiagnosed as Rocky Mountain spotted fever, and that suspicion of other SFGR as well as Ehrlichia should be increased. These data may be of relevance to other regions where A. americanum is prevalent

Making Room for Zoom in Focus Group Methods: Opportunities and Challenges for Novice Researchers (During and Beyond COVID-19)

Als die COVID-19-Pandemie über die Welt hereinbrach, waren viele Menschen gezwungen, sich auf online-basierte Routinen einzustellen, darunter auch qualitative Forscher*innen, die nach alternativen Möglichkeiten zur Erhebung aussagekräftiger Daten suchten. Während Fokusgruppen traditionell Face to Face durchgeführt werden, bieten Fortschritte bei Online-Videokonferenzanwendungen neue Methoden zur Datenerhebung, die jedoch bisher nur selten untersucht wurden. In diesem Artikel berichten wir über die Erfahrungen von 12 Doktorand*innen mit der Durchführung von Fokusgruppen unter Verwendung von Zoom im Rahmen eines Kurses zu qualitativen Interviewmethoden. Wir reflektieren Chancen und Herausforderungen, die wir als Moderator*innen und Teilnehmer*innen bei der Nutzung von Zoom erlebten z.B. bei der Vorbereitung oder in Bezug auf Rapport, die Einbindung anderer digitaler Tools und von Internetverbindungen. Zusammenfassend lässt sich sagen, dass die Durchführung von Online-Fokusgruppen unter Verwendung von Zoom insgesamt eine positive Erfahrung war und mit Face-to-Face-Fokusgruppen vergleichbar ist. Möglichkeiten der Teilnehmer*innenrekrutierung, die Sicherheitsmerkmale von Zoom und die Nutzung von Zoom und allgemeiner neuen Technologien sollten auch jenseits der Pandemie weiter erforscht werden.As the COVID-19 pandemic swept through the world, it forced many people to adapt to an online-based routine, including qualitative researchers looking for alternative ways to collect meaningful data. While focus groups are traditionally conducted in-person, advances with online videoconferencing applications present a new method to collect data, however, few studies have explored this. In this article we present 12 doctoral students' experiences with conducting focus groups using the videoconferencing application Zoom during a qualitative methods course on interviewing methods. Through this self-study qualitative analysis, participants reflected on the opportunities and challenges experienced as both moderators and participants using Zoom including: preparation, rapport, incorporating other digital tools, and internet connectivity. In conclusion, doing focus groups online using Zoom was a positive experience overall and comparable to in-person focus groups for collecting qualitative data, despite the introduction of technology. More research on participant recruitment, new technology, Zoom's security features, and Zoom's use outside of a pandemic should be further explored

Effect of routine probiotic, Lactobacillus reuteri DSM 17938, use on rates of necrotizing enterocolitis in neonates with birthweight < 1000 grams: a sequential analysis

BackgroundNecrotizing enterocolitis (NEC) is a disease in neonates, often resulting in death or serious medical or neurodevelopmental complications. The rate of NEC is highest in the smallest babies and many efforts have been tried to reduce the rate of NEC. In neonates born below 1500 grams, the rate of NEC has been significantly reduced with the use of various probiotics. This study examines the impact of routine use of a probiotic, Lactobacillus reuteri DSM 17938 (BioGaia®), on the rate of NEC in neonates at highest risk for developing NEC, those with birth weight ≤1000 grams.MethodsThis is a retrospective cohort study comparing the rates of NEC in neonates with birth weight ≤ 1000 grams. The groups are separated into those neonates born from January 2004 to June 30, 2009, before introduction of L. reuteri , and neonates born July 2009 through April 2011 who received routine L. reuteri prophylaxis. The chart review study was approved by our institutional review board and exempted from informed consent.Neonates were excluded if they died or were transferred within the first week of life. The remainder were categorized as having no NEC, medical NEC, surgical NEC, or NEC associated death. Since no major changes occurred in our NICU practice in recent years, and the introduction of L. reuteri as routine prophylaxis was abrupt, we attributed the post-probiotic changes to the introduction of this new therapy. Rates of NEC were compared using Chi square analysis with Fisher exact t-test.ResultsMedical records for 311 neonates were reviewed, 232 before- and 79 after-introduction of L. reuteri prophylaxis. The incidence of NEC was significantly lower in the neonates who received L. reuteri (2 of 79 neonates [2.5%] versus 35 of 232 untreated neonates [15.1%]). Rates of late-onset gram-negative or fungal infections (22.8 versus 31%) were not statistically different between treated and untreated groups. No adverse events related to use of L reuteri were noted.ConclusionsProphylactic initiation of L. reuteri as a probiotic for prevention of necrotizing enterocolitis resulted in a statistically significant benefit, with avoidance of 1 NEC case for every 8 patients given prophylaxis

TESS Discovery of a Transiting Super-Earth in the π\pi Mensae System

We report the detection of a transiting planet around $\pi$ Mensae (HD 39091), using data from the Transiting Exoplanet Survey Satellite (TESS). The solar-type host star is unusually bright (V=5.7) and was already known to host a Jovian planet on a highly eccentric, 5.7-year orbit. The newly discovered planet has a size of $2.04\pm 0.05$ $R_\oplus$ and an orbital period of 6.27 days. Radial-velocity data from the HARPS and AAT/UCLES archives also displays a 6.27-day periodicity, confirming the existence of the planet and leading to a mass determination of $4.82\pm 0.85$ $M_\oplus$. The star's proximity and brightness will facilitate further investigations, such as atmospheric spectroscopy, asteroseismology, the Rossiter--McLaughlin effect, astrometry, and direct imaging.Comment: Accepted for publication ApJ Letters. This letter makes use of the TESS Alert data, which is currently in a beta test phase. The discovery light curve is included in a table inside the arxiv submissio

Genomic Profiling of Childhood Tumor Patient-Derived Xenograft Models to Enable Rational Clinical Trial Design.

Accelerating cures for children with cancer remains an immediate challenge as a result of extensive oncogenic heterogeneity between and within histologies, distinct molecular mechanisms evolving between diagnosis and relapsed disease, and limited therapeutic options. To systematically prioritize and rationally test novel agents in preclinical murine models, researchers within the Pediatric Preclinical Testing Consortium are continuously developing patient-derived xenografts (PDXs)-many of which are refractory to current standard-of-care treatments-from high-risk childhood cancers. Here, we genomically characterize 261 PDX models from 37 unique pediatric cancers; demonstrate faithful recapitulation of histologies and subtypes; and refine our understanding of relapsed disease. In addition, we use expression signatures to classify tumors for TP53 and NF1 pathway inactivation. We anticipate that these data will serve as a resource for pediatric oncology drug development and will guide rational clinical trial design for children with cancer

Argumentation in school science : Breaking the tradition of authoritative exposition through a pedagogy that promotes discussion and reasoning

The value of argumentation in science education has become internationally recognised and has been the subject of many research studies in recent years. Successful introduction of argumentation activities in learning contexts involves extending teaching goals beyond the understanding of facts and concepts, to include an emphasis on cognitive and metacognitive processes, epistemic criteria and reasoning. The authors focus on the difficulties inherent in shifting a tradition of teaching from one dominated by authoritative exposition to one that is more dialogic, involving small-group discussion based on tasks that stimulate argumentation. The paper builds on previous research on enhancing the quality of argument in school science, to focus on how argumentation activities have been designed, with appropriate strategies, resources and modelling, for pedagogical purposes. The paper analyses design frameworks, their contexts and lesson plans, to evaluate their potential for enhancing reasoning through foregrounding the processes of argumentation. Examples of classroom dialogue where teachers adopt the frameworks/plans are analysed to show how argumentation processes are scaffolded. The analysis shows that several layers of interpretation are needed and these layers need to be aligned for successful implementation. The analysis serves to highlight the potential and limitations of the design frameworks