Is Fitspiration Truly an Inspiration? Relationships between Fitspiration, Exercise, and Body Image

Young adults across the United States struggle to meet physical activity recommendations and consume healthy diets, and they often suffer from issues related to body image. Social media influencers dedicated to fitspiration (i.e., fitness inspiration) are purported to have a goal of inspiring others to lead healthier lifestyles. The purpose of this study was to explore the relationships between fitspiration and exercise and body image perceptions amongst college students. Participants (n = 361, mean age = 20.2 years, 78% female) completed surveys that included sociodemographic information, social media usage, fitspiration content engagement, exercise, and body satisfaction. An independent samples t-test assessed differences in exercise by fitspiration viewership, and a chi-square analysis determined relationships between fitspiration and body satisfaction. Participants were routinely active on social media (91% use it for \u3e 1 hour per day), and 61.5% were exposed to fitspiration content. Approximately 41% of respondents have followed exercise advice from fitspiration influencers, though only 11% reported having purchased products. No relationships were reported between following fitspiration and days per week of exercise (M∆ = .02(.20), p = .91). Participants that followed fitspiration were more likely to be dissatisfied with their bodies, X2 (1, n = 316) =7.77, p = .005, compared to participants who did not. Findings demonstrate fitspiration was not related to exercise and was related to poorer body image perceptions among college students. These results are supported by previous findings and indicate a critical misalignment between the purported purpose of fitspiration and the outcome of its viewing

Effects of Hypohydration on Muscular Performance in Females: An Ongoing Study

Dehydration (~3%) has been shown to negatively affect anaerobic performance. A majority of this research has been conducted using male participants. Like males, females have been shown to underestimate sweat loss, which could lead to insufficient rehydration and thus hypohydration. Additionally, due to differences in thermoregulation, it is possible that females respond to hypohydration differently than males. To date, no research has examined the effects of previous night dehydration on muscular performance in females. PURPOSE: The purpose of this ongoing study was to determine the effects of previous night dehydration on muscular strength, muscular endurance, lower body power, and perceptual measures in resistance trained females. METHODS: Healthy, resistance trained females (n = 7) completed two bouts of resistance exercise, either dehydrated (~3% body weight) (DT) or heat exposed with fluid replacement (HT). Each exercise bout consisted of one rep maximum (1RM) for bench press followed by 5 sets to failure of 75% of 1RM, 1RM for leg press followed by 5 sets to failure of 75% of 1RM, and vertical jump assessment. Participants estimated ratings of perceived exertion (RPE) after each exercise. Session RPE (SRPE) was estimated 5 minutes following completion of the protocol and estimations for feelings of recovery (PRS), perceived readiness to exercise (PR), thirst, and sleep quality were estimated prior to workouts. RESULTS: Analysis revealed a bench press 1RM (p = 0.05) and leg press 1RM (p = 0.03) were significantly lower for DT (bench: 95.0 ± 34.0; leg press: 461.4 ± 141.7) compared to HT (bench: 97.9 ± 34.3; leg press: 500.0 ± 141.0). There was no difference in total reps completed for bench press (p = 0.32) or leg press (p = 0.37) for DT (bench press: 31.0 ± 6.7; leg press: 47.9 ± 21.6) compared to HT (bench press: 31.7 ± 5.0; leg press: 49.6 ± 22.8). There was no significant difference (p = 0.15) for vertical jump height (DT: 17.6 ± 2.2, HT: 18.1 ± 2.6). RPE was not significantly different following bench press (p = 0.5) (DT: 7.1 ± 1.1, HT: 7.1 ± 0.9) or leg press (p = 0.41) (DT: 6.7 ± 0.5, HT: 6.9 ± 1.7). SRPE was significantly higher (p = 0.05) for DT (6.6 ± 0.5) vs HT (5.9 ± 0.7). Significant differences for PRS (p = 0.03) (DT: 5.4 ± 2.2, HT: 7.05 ± 1.3) and PR (p = 0.01) (DT: 3.9 ± 0.9, HT: 2.6 ± 0.5) indicate participants expected impaired performance during DT. Feelings of thirst were significantly higher (p = 0.001) for DT (6.5 ± 2.5) vs HT (2.1 ± 2.3). Estimations of sleep quality were significantly lower (p = 0.05) for DT (4.3 ± 3.3) vs HT (7.2 ± 2.1). CONCLUSION: Even though only preliminary data from a presently ongoing study, the current results suggest that previous night dehydration has a negative influence on both performance and perceptual measures in resistance trained females

Effects of Dehydration on Resistance Training: An Ongoing Study

Introduction: Dehydration via hot bath has been shown to impair resistance training performance when performed the same day. The performance decrements in this instance could potentially be due to a combination of the dehydration and residual effects of the heat exposure and not of the dehydration alone. To date, no research has examined the effects of previous night dehydration on resistance training performance. Purpose: The purpose of this ongoing study was to determine the effects of previous night dehydration on performance and perceptual measures during a full-body resistance training protocol. Methods: Healthy, resistance trained males (n = 4) completed two bouts of a full body resistance training protocol (three sets to failure for bench press, lat pull, overhead press, bicep curl, triceps push down, and leg press), dehydrated (~3% body weight) (DT), or heat exposed with fluid replacement (HT). Heart rate (HR) was taken after every set, and participants estimated ratings of perceived exertion (RPE) after each exercise. Session RPE (SRPE) was estimated 5 minutes following completion of the protocol and estimations for feelings of recovery (PRS), perceived readiness to exercise (PR), thirst, and sleep quality. Results: Analysis revealed a significantly less (p = \u3c 0.001) total reps were completed for DT (163.0 ± 4.8) compared to HT (191.3 ± 10.3), though no differences were found for reps per exercise. No significant differences were found for HR (DT vs HT) at any time point. RPE was significantly higher for DT following bicep curl (p = 0.03) (DT: 7.8 ± 0.96, HT: 6.0 ± 0.82) and triceps push down (p = 0.03) (DT: 7.5 ± 0.58, HT: 6.0 ± 0.82). SRPE was significantly higher (p = 0.003) for DT (8.0 ± 0.0) vs HT (6.3 ± 0.5). Significant differences for PRS (p = 0.004) (DT: 5.0 ± 1.4, HT: 7.5 ± 0.58) and PR (p = \u3c 0.001) (DT: 5.0 ± 0.0, HT: 2.5 ± 0.58) indicate participants expected impaired performance during DT. Feelings of thirst were significantly higher (p = 0.001) for DT (7.98 ± 0.94) vs HT (2.73 ± 1.11). No differences were found for estimations of sleep quality (p = 0.59). Conclusion: Even though only preliminary data from a study presently ongoing, the present results suggest that previous night dehydration has a negative influence on both performance and perceptual measures

The VLTI/MIDI survey of massive young stellar objects - Sounding the inner regions around intermediate- and high-mass young stars using mid-infrared interferometry

We aim to characterize the distribution and composition of circumstellar material around young massive stars, and to investigate exactly which physical structures in these objects are probed by long-baseline mid-infrared interferometric observations. We used the two-telescope interferometric instrument MIDI of the Very Large Telescope Interferometer of the European Southern Observatory to observe a sample of 24 intermediate- and high-mass young stellar objects in the N band (8-13 micron). We had successful fringe detections for 20 objects, and present spectrally-resolved correlated fluxes and visibility levels for projected baselines of up to 128 m. We fit the visibilities with geometric models to derive the sizes of the emitting regions, as well as the orientation and elongation of the circumstellar material. Fourteen objects in the sample show the 10 micron silicate feature in absorption in the total and correlated flux spectra. For 13 of these objects, we were able to fit the correlated flux spectra with a simple absorption model, allowing us to constrain the composition and absorptive properties of the circumstellar material. Nearly all of the massive young stellar objects observed show significant deviations from spherical symmetry at mid-infrared wavelengths. In general, the mid-infrared emission can trace both disks and outflows, and in many cases it may be difficult to disentangle these components on the basis of interferometric data alone, because of the sparse spatial frequency coverage normally provided by current long-baseline interferometers. For the majority of the objects in this sample, the absorption occurs on spatial scales larger than those probed by MIDI. Finally, the physical extent of the mid-infrared emission around these sources is correlated with the total luminosity, albeit with significant scatter.Comment: 36 pages, 22 figures. Accepted to Astronomy and Astrophysic

Evaluating categories of resistance in soybean genotypes from the United States and Brazil to \u3ci\u3eAphis glycines\u3c/i\u3e (Hemiptera: Aphididae)

Aphis glycines Matsumura (Hemiptera: Aphididae), the soybean aphid, has become an important pest of soybeans, leading to significant yield losses in the United States. Host plant resistance is a viable alternative for managing A. glycines. The objectives of this study were to identify and categorize sources of resistance in soybean to A. glycines on genotypes from the United States and Brazil. An antixenosis assay was initially conducted with 8 genotypes to evaluate attractiveness to A. glycines. The selected soybean genotypes were further evaluated in a colonization assay to investigate the resistance of the genotypes at V1 (fully developed leaves at unifoliate node, 1st trifoliate leaf unrolled) and V3 (fully developed leaf at 2nd trifoliate node, 3rd trifoliate leaf unrolled) stages. An antibiosis assay was also conducted, in which multiple biological parameters of A. glycines were recorded. In the antixenosis assay, PI 200538, IAC 24, and IAC 17 genotypes were least attractive to adults of A. glycines, indicating moderate levels of antixenosis. The colonization assay showed that genotypes infested at the V3 stage had greater resistance when compared with the respective plants infested at the V1 stage. In addition, high levels of antibiosis to A. glycines were found in UX 2569-159, PI 200538, and PI 243540 genotypes. The identification of soybeans with resistance to A. glycines is of importance for the integrated pest management of this insect pest in the United States. Moreover, this research represents the first report on potential sources of resistance to A. glycines in soybeans from Brazil. O pulgão-da-soja, Aphis glycines Matsumura (Hemiptera: Aphididae), tornou-se uma importante praga da soja, levando a significativas perdas de produção nos Estados Unidos da América (EUA). A resistência de plantas é considerada uma alternativa viável para o manejo de A. glycines. Os objetivos deste estudo foram identificar e categorizar fontes de resistência em soja a A. glycines, avaliando genótipos dessa leguminosa do Brasil e EUA. Um ensaio de antixenose foi conduzido inicialmente com oito genótipos de soja a fim de avaliar a atratividade de A. glycines. Os genótipos selecionados foram posteriormente avaliados em um ensaio de colonização, visando verificar sua resistência nos estádios V1 (folhas do primeiro nó totalmente desenvolvidas; primeiro trifólio aberto) e V3 (folhas do segundo trifólio totalmente desenvolvidas; folhas do terceiro trifólio abertas). Um ensaio de antibiose também foi realizado, avaliando-se diversos parâmetros biológicos de A. glycines. No ensaio de antixenose, os genótipos PI 200538, IAC 24 e IAC 17 foram menos atrativos a adultos de A. glycines, indicando níveis moderados de antixenose. O ensaio de colonização mostrou que genótipos de soja infestados no estádio V3 apresentam maior resistência em comparação com plantas infestadas no estádio V1. Em adição, este estudo constatou altos níveis de antibiose para A. glycines nos genótipos UX 2569-159, PI 200538 e PI 243540. A identificação de genótipos de soja com resistência a A. glycines é importante para os programas de manejo integrado de pragas (MIP) nos EUA. Em adição, esta pesquisa apresenta o primeiro registro de genótipos de soja brasileiros como potenciais fontes de resistência ao pulgão-da-soja

Electrochromically switched, gas-reservoir metal hydride devices with application to energy-efficient windows

Proof-of-principle gas-reservoir MnNiMg electrochromic mirror devices have been investigated. In contrast to conventional electrochromic approaches, hydrogen is stored (at low concentration) in the gas volume between glass panes of the insulated glass units (IGUs). The elimination of a solid state ion storage layer simplifies the layer stack, enhances overall transmission, and reduces cost. The cyclic switching properties were demonstrated and system durability improved with the incorporation a thin Zr barrier layer between the MnNiMg layer and the Pd catalyst. Addition of 9 percent silver to the palladium catalyst further improved system durability. About 100 full cycles have been demonstrated before devices slow considerably. Degradation of device performance appears to be related to Pd catalyst mobility, rather than delamination or metal layer oxidation issues originally presumed likely to present significant challenges

Liver Monocytes and Kupffer Cells Remain Transcriptionally Distinct during Chronic Viral Infection

Due to the scarcity of immunocompetent animal models for chronic viral hepatitis, little is known about the role of the innate intrahepatic immune system during viral replication in the liver. These insights are however fundamental for the understanding of the inappropriate adaptive immune responses during the chronic phase of the infection. We apply the Lymphocytic Choriomenigitis Virus (LCMV) clone 13 mouse model to examine chronic virus-host interactions of Kupffer cells (KC) and infiltrating monocytes (IM) in an infected liver. LCMV infection induced overt clinical hepatitis, with rise in ALT and serum cytokines, and increased intrahepatic F4/80 expression. Despite ongoing viral replication, whole liver transcriptome showed baseline expression levels of inflammatory cytokines, interferons, and interferon induced genes during the chronic infection phase. Transcriptome analyses of sorted KC and IMs using NanoString technology revealed two unique phenotypes with only minimal overlap. At the chronic viral infection phase, KC showed no increased transcription of activation markers Cd80 and Cd86, but an increased expression of genes related to antigen presentation, whereas monocytes were more activated and expressed higher levels of Tnf transcripts. Although both KCs and intrahepatic IM share the surface markers F4/80 and CD11b, their transcriptomes point towards distinctive roles during virus-induced chronic hepatitis

Connexin43 ablation in foetal atrial myocytes decreases electrical coupling, partner connexins, and sodium current

Aims Remodelling and regional gradients in expression of connexins (Cx) are thought to contribute to atrial electrical dysfunction and atrial fibrillation. We assessed the effect of interaction between Cx43, Cx40, and Cx45 on atrial cell-to-cell coupling and inward Na current (INa) in engineered pairs of atrial myocytes derived from wild-type mice (Cx43+/+) and mice with genetic ablation of Cx43 (Cx43−/−). Methods and results Cell pairs were engineered by microcontact printing from atrial Cx43+/+ and Cx43−/− murine myocytes (1 day before birth, 3-5 days in culture). Dual and single voltage clamp were used to measure intercellular electrical conductance, gj, and its dependence on transjunctional voltage, Vj, single gap junction channel conductances, and INa. 3D reconstructions of Cx43, Cx40, and Cx45 immunosignals in gap junctions were made from confocal slices. Full genetic Cx43 ablation produced a decrease in immunosignals of Cx40 to 62 ± 10% (mean ± SE; n= 17) and Cx45 to 66 ± 8% (n= 16). Gj decreased from 80 ± 9 nS (Cx43+/+, n= 17) to 24 ± 2 nS (Cx43−/−, n= 35). Single channel analysis showed a shift in the main peak of the channel histogram from 49 ± 1.7 nS (Cx43+/+) to 67 ± 1.8 nS (Cx43−/−) with a second minor peak appearing at 27 ± 1.5 pS. The dependence of gj on Vj decreased with Cx43 ablation. Importantly, peak INa decreased from −350 ± 44 pA/pF (Cx43+/+) to −154 ± 28 pA/pF (Cx43−/−). Conclusions The dependence of Cx40, Cx45, and INa on Cx43 expression indicates a complex interaction between connexins and INa in the atrial intercalated discs that is likely to be of relevance for arrhythmogenesi

Cytoskeletal variations in an asymmetric cell division support diversity in nematode sperm size and sex ratios

Asymmetric partitioning is an essential component of many developmental processes. As spermatogenesis concludes, sperm are streamlined by discarding unnecessary cellular components into cellular wastebags called residual bodies (RBs). During nematode spermatogenesis, this asymmetric partitioning event occurs shortly after anaphase II, and both microtubules and actin partition into a central RB. Here, we use fluorescence and transmission electron microscopy to elucidate and compare the intermediate steps of RB formation in Caenorhabditis elegans, Rhabditis sp. SB347 (recently named Auanema rhodensis) and related nematodes. In all cases, intact microtubules reorganize and move from centrosomal to non-centrosomal sites at the RB-sperm boundary whereas actin reorganizes through cortical ring expansion and clearance from the poles. However, in species with tiny spermatocytes, these cytoskeletal changes are restricted to one pole. Consequently, partitioning yields one functional sperm with the X-bearing chromosome complement and an RB with the other chromosome set. Unipolar partitioning may not require an unpaired X, as it also occurs in XX spermatocytes. Instead, constraints related to spermatocyte downsizing may have contributed to the evolution of a sperm cell equivalent to female polar bodies