Dietary niche partitioning in Early Jurassic ichthyosaurs from Strawberry Bank

Jurassic ichthyosaurs dominated upper trophic levels of marine ecosystems. Many species coexisted alongside each another, and it is uncertain whether they competed for the same array of food or divided dietary resources, each specializing in different kinds of prey. Here, we test whether feeding differences existed between species, applying finite element analysis to ichthyosaurs for the first time. We examine two juvenile ichthyosaur specimens, referred to Hauffiopteryx typicus and Stenopterygius triscissus, from the Strawberry Bank Lagerstätte, a shallow marine environment from the Early Jurassic of southern England (Toarcian, ~183 Ma). Snout and cranial robusticity differ between the species, with S. triscissus having a more robust snout and cranium and specializing in slow biting of hard prey, and H. typicus with its slender snout specializing in fast, but weaker bites on fast‐moving, but soft prey. The two species did not differ in muscle forces, but stress distributions varied in the nasal area, reflecting differences when biting at different points along the tooth row: the more robustly snouted Stenopterygius resisted increases or shifts in stress distribution when the bite point was shifted from the posterior to the mid‐point of the tooth row, but the slender‐snouted Hauffiopteryx showed shifts and increases in stress distributions between these two bite points. The differences in cranial morphology, dentition and inferred stresses between the two species suggest adaptations for dietary niche partitioning

Solution structure of a bacterial microcompartment targeting peptide and its application in the construction of an ethanol bioreactor

Targeting of proteins to bacterial microcompartments (BMCs) is mediated by an 18-amino-acid peptide sequence. Herein, we report the solution structure of the N-terminal targeting peptide (P18) of PduP, the aldehyde dehydrogenase associated with the 1,2-propanediol utilization metabolosome from Citrobacter freundii. The solution structure reveals the peptide to have a well-defined helical conformation along its whole length. Saturation transfer difference and transferred NOE NMR has highlighted the observed interaction surface on the peptide with its main interacting shell protein, PduK. By tagging both a pyruvate decarboxylase and an alcohol dehydrogenase with targeting peptides, it has been possible to direct these enzymes to empty BMCs in vivo and to generate an ethanol bioreactor. Not only are the purified, redesigned BMCs able to transform pyruvate into ethanol efficiently, but the strains containing the modified BMCs produce elevated levels of alcohol

The Effects of Video Instruction Versus Verbal Instruction on High Intensity Interval Exercise Performance: A Pilot Analysis

It has been indicated that music and motivational videos can have a positive impact on high-intensity treadmill performance in trained athletes. It has also been shown that live or recorded video exercise instructions have an overall positive effect on exercise performance accuracy in upper extremity exercises compared to written or verbal instructions in adults with no shoulder pathologies. It is unclear whether exercise instructions given via a home workout video has any effects on non-equipment based high-intensity interval exercise performance. Purpose: The purpose of this study was to determine whether exercising along with pre-recorded video instructions positively impacts overall exercise performance in a single bout of Tabata exercise compared to verbal and handout instructions alone. Methods: In this cross-over design, 8 (2F; 6M) sedentary, college-aged (171.5±40.7 lbs; 67.6±3in; 21.3±1.5yrs) individuals participated in two randomized intervention groups: 1) Tabata with video instructions on a computer screen (V) and 2) Tabata without video instruction (NV). The Tabata workout consisted of five total sessions. Each session was composed of two rounds, with each round containing four exercises each lasting 20 seconds followed by 10 seconds of rest. Following the completion of a session, participants were given a 60 second rest period. The total duration of the exercise was 25 minutes. During the recovery period, the participants’ heart rate (HR) and ratings of perceived exertion (RPE) were recorded. Prior(pre) and immediately following the completion of exercise(post), participants were given the felt arousal scale (FAS) and the 10-centimeter visual analog fatigue scale (FS) to assess participants arousal and overall fatigue. Significant differences (p\u3c0.05) for average RPE for each trial along with the pre and post FAS and FS for each trial was determined using a Wilcoxon Signed-Rank test. Significant differences between HR were analyzed using a Student\u27s T-test (p\u3c0.05). Results: The results of the dependent samples Wilcoxon test did not reveal any significant differences between NVFASPre and VFASpre (p=0.783), NVFASpost and VFASpost (p=0.71), NVFSpre and VFSpre (p=.401), NVFSpost and VFSpost (p=0.401) and NVRPE and VRPE (p=0.779). The student\u27s t-test also did not reveal any significant differences between NVHR and VHR (174.3 ± 18.4 & 174.3 ± 13.2 BPM; p=.359). Conclusion: The findings of this study suggest that there was no significant difference in exercise performance, arousal, intensity, and fatigue between instructions given visually or verbally. However, the preference of the participants for instruction was verbal rather than visual. Comments from the participants included that the person demonstrating the exercises in the video reduced their self-efficacy, because they could not keep up. Limitations of this study were the small sample size, not counting the number of repetitions for each exercise, and population of the participants. Future research should address these limitations

Psychology students’ perception of and engagement with feedback as a function of year of study

Undergraduate students’ perception of feedback and level of engagement with the feedback they receive have gained increasing attention in the educational literature recently to identify areas which require educators’ attention. However, research in this area has generally been based on limited self-selecting samples, and has not considered how students’ relationship with feedback may alter depending on their year of study. To address this, a survey measuring students’ views and practices regarding feedback was completed at a higher education institution by 447 first-, second- and third-year psychology students, representing 77% of the cohort. Findings revealed that third years responded more negatively in both areas than their first- and second-year counterparts, whose ratings on these aspects themselves were far from optimal. These findings highlight the need for early interventions to improve students’ perception of and engagement with feedback in the earlier years, and to prevent the recorded deterioration later on in the degree course

A phenomenological inquiry into the lived experience of adults diagnosed with Attention Deficit Hyperactivity Disorder (ADHD) employed by the NHS

Purpose: Approximately 3.5% of the workforce is diagnosed with attention deficit hyperactivity disorder (ADHD). With a greater risk of work-related stress and absences, work-based social interactions and environments are significant factors. The purpose of this study was to identify the professional challenges and benefits of living with ADHD in healthcare settings. Design/methodology/approach: Interpretative phenomenological analysis was used to explore how employees with ADHD both experience and make sense of their employment and professional relationships. Participants self-identified from two NHS trusts and participated in semi-structured interviews. Findings: A total of seven interviews contributed to the final analysis. A total of four themes emerged: social environment (relationships), physical environment, behaviour and work tasks. Complex interactions were observed between individuals’ internal constructs and overall employment experience. Practical implications: The findings can be used to inform local NHS management frameworks for supporting workforce with ADHD. Originality/value: This is a novel study that explores the psychodynamic and physical presentations of ADHD providing a unique perspective on the challenges and strengths of employees with ADHD

Microevolution of Group A Streptococci In Vivo: Capturing Regulatory Networks Engaged in Sociomicrobiology, Niche Adaptation, and Hypervirulence

The onset of infection and the switch from primary to secondary niches are dramatic environmental changes that not only alter bacterial transcriptional programs, but also perturb their sociomicrobiology, often driving minor subpopulations with mutant phenotypes to prevail in specific niches. Having previously reported that M1T1 Streptococcus pyogenes become hypervirulent in mice due to selection of mutants in the covRS regulatory genes, we set out to dissect the impact of these mutations in vitro and in vivo from the impact of other adaptive events. Using a murine subcutaneous chamber model to sample the bacteria prior to selection or expansion of mutants, we compared gene expression dynamics of wild type (WT) and previously isolated animal-passaged (AP) covS mutant bacteria both in vitro and in vivo, and we found extensive transcriptional alterations of pathoadaptive and metabolic gene sets associated with invasion, immune evasion, tissue-dissemination, and metabolic reprogramming. In contrast to the virulence-associated differences between WT and AP bacteria, Phenotype Microarray analysis showed minor in vitro phenotypic differences between the two isogenic variants. Additionally, our results reflect that WT bacteria's rapid host-adaptive transcriptional reprogramming was not sufficient for their survival, and they were outnumbered by hypervirulent covS mutants with SpeB−/Sdahigh phenotype, which survived up to 14 days in mice chambers. Our findings demonstrate the engagement of unique regulatory modules in niche adaptation, implicate a critical role for bacterial genetic heterogeneity that surpasses transcriptional in vivo adaptation, and portray the dynamics underlying the selection of hypervirulent covS mutants over their parental WT cells

Studying the atmosphere of the exoplanet HAT-P-7b via secondary eclipse measurements with EPOXI, Spitzer and Kepler

The highly irradiated transiting exoplanet, HAT-P-7b, currently provides one of the best opportunities for studying planetary emission in the optical and infrared wavelengths. We observe six near-consecutive secondary eclipses of HAT-P-7b at optical wavelengths with the EPOXI spacecraft. We place an upper limit on the relative eclipse depth of 0.055% (95% confidence). We also analyze Spitzer observations of the same target in the infrared, obtaining secondary eclipse depths of 0.098+/-0.017%, 0.159+/-0.022%, 0.245+/-0.031% and 0.225+/-0.052% in the 3.6, 4.5, 5.8 and 8.0 micron IRAC bands respectively. We combine these measurements with the recently published Kepler secondary eclipse measurement, and generate atmospheric models for the day-side of the planet that are consistent with both the optical and infrared measurements. The data are best fit by models with a temperature inversion, as expected from the high incident flux. The models predict a low optical albedo of ~< 0.13, with subsolar abundances of Na, K, TiO and VO. We also find that the best fitting models predict that 10% of the absorbed stellar flux is redistributed to the night side of the planet, which is qualitatively consistent with the inefficient day-night redistribution apparent in the Kepler phase curve. Models without thermal inversions fit the data only at the 1.25 sigma level, and also require an overabundance of methane, which is not expected in the very hot atmosphere of HAT-P-7b. We also analyze the eight transits of HAT-P-7b present in the EPOXI dataset and improve the constraints on the system parameters, finding a period of P = 2.2047308+/-0.0000025 days, a stellar radius of R* = 1.824+/-0.089Rsun, a planetary radius of Rp = 1.342+/-0.068RJup and an inclination of i = 85.7+3.5-2.2 deg.Comment: 21 pages, 8 figures, accepted by the Astrophysical Journa