Flight Respiration and Energetics

We Use a Comparative Approach to Examine Some of the Physiological Traits that Make Flight Possible. Comparisons of Related Fliers and Runners Suggest that Fliers Generally Have Higher Aerobic Metabolic Capacities Than Runners But that the Difference is Highly Dependent on the Taxa Studied. the High Metabolic Rates of Fliers Relative to Runners, Especially in Insects, Are Correlated with High Locomotory Muscle Cycle Frequencies and Low Efficiencies of Conversion of Metabolic Power to Mechanical Power. We Examine Some Factors that Produce Variation in Flight Respiration and Energetics. Air Temperature Strongly Affects the Flight Metabolic Rote of Some Insects and Birds. Flight Speed Interacts with Flier Mass, So that Small Fliers Tend to Exhibit a J-Shaped Power Curve and Larger Fliers a U-Shaped Power Curve. as Body Size Increases, Mass-Specific Aerobic Flight Metabolism Decreases in Most Studies, But Mass-Specific Power Output is Constant or Increases, Leading to an Increase in Efficiency with Size. Intraspecific Studies Have Revealed Specific Genetically based Effects on Flight Metabolism and Power Output and Multiple Ecological Correlates of Flight Capabilities

Crystal Structure of the Yeast Inner Kinetochore Subunit cep3p

In budding yeast, the four-protein CBF3 complex (Skp1p-Ctf13p-Cep3p-Ndc10p) initiates kinetochore assembly by binding to the CDEIII locus of centromeric DNA. A Cep3p dimer recruits a Ctf13p-Skp1p heterodimer and contacts two sites on CDEIII. We report here the crystal structure, determined at 2.8 Å resolution by multiple isomorphous replacement with anomalous scattering, of a truncated Cep3p [Cep3p (47−608)], comprising all but an N-terminal, Zn2Cys6-cluster, DNAbinding module. Cep3p has a well-ordered structure throughout essentially all of its polypeptide chain, unlike most yeast transcription factors, including those with Zn2Cys6 clusters like Gal4p. This difference may reflect an underlying functional distinction: while any particular transcription factor must adapt to a variety of upstream activating sites, Cep3p scaffolds kinetochore assembly on centromeres uniformly configured on all 16 yeast chromosomes. We have, using the structure of Cep3p (47−603) and the known structures of Zn2Cys6 cluster domains, modeled the interaction of Cep3p with CDEIII.Chemistry and Chemical Biolog

Consumer insights and the importance of competitiveness Factors for mature and developing destinations

This article aims to understand the importance of various destination attributes to the competitiveness of tourism destinations from a consumer perspective, while at the same time contrasting these in a mature versus developing destination. A sample of Australian-based domestic tourists were surveyed to assess the relative importance of tourism destination competitiveness (TDC) attributes in the context of developing and mature destinations. This research firstly appears to verify that the importance of many TDC elements, highlighted by consumers, is not dissimilar from other stakeholder-based TDC studies. Furthermore, this research effort established that in terms of attribute performance, relative destination immaturity may well constrain a developing destination’s ability to satisfy the needs of consumers

Greenhouse gas balance over thaw-freeze cycles in discontinuous zone permafrost

Peat in the discontinuous permafrost zone contains a globally significant reservoir of carbon that has undergone multiple permafrost-thaw cycles since the end of the mid-Holocene (~3700 years before present). Periods of thaw increase C decomposition rates which leads to the release of CO2 and CH4 to the atmosphere creating potential climate feedback. To determine the magnitude and direction of such feedback, we measured CO2 and CH4 emissions and modeled C accumulation rates and radiative fluxes from measurements of two radioactive tracers with differing lifetimes to describe the C balance of the peatland over multiple permafrost-thaw cycles since the initiation of permafrost at the site. At thaw features, the balance between increased primary production and higher CH4 emission stimulated by warmer temperatures and wetter conditions favors C sequestration and enhanced peat accumulation. Flux measurements suggest that frozen plateaus may intermittently (order of years to decades) act as CO2 sources depending on temperature and net ecosystem respiration rates, but modeling results suggest that—despite brief periods of net C loss to the atmosphere at the initiation of thaw—integrated over millennia, these sites have acted as net C sinks via peat accumulation. In greenhouse gas terms, the transition from frozen permafrost to thawed wetland is accompanied by increasing CO2 uptake that is partially offset by increasing CH4 emissions. In the short-term (decadal time scale) the net effect of this transition is likely enhanced warming via increased radiative C emissions, while in the long-term (centuries) net C deposition provides a negative feedback to climate warming

Lipid coated liquid crystal droplets for the on-chip detection of antimicrobial peptides

We describe a novel biosensor based on phospholipid-coated nematic liquid crystal (LC) droplets and demonstrate the detection of Smp43, a model antimicrobial peptide (AMP) from the venom of North African scorpion Scorpio maurus palmatus. Mono-disperse lipid-coated LC droplets of diameter 16.7 ± 0.2 μm were generated using PDMS microfluidic devices with a flow-focusing configuration and were the target for AMPs. The droplets were trapped in a bespoke microfluidic trap structure and were simultaneously treated with Smp43 at gradient concentrations in six different chambers. The disruption of the lipid monolayer by the Smp43 was detected (<6 μM) at concentrations well within its biologically active range, indicated by a dramatic change in the appearance of the droplets associated with the transition from a typical radial configuration to a bipolar configuration, which is readily observed by polarizing microscopy. This suggests the system has feasibility as a drug-discovery screening tool. Further, compared to previously reported LC droplet biosensors, this LC droplet biosensor with a lipid coating is more biologically relevant and its ease of use in detecting membrane-related biological processes and interactions has the potential for development as a reliable, low-cost and disposable point of care diagnostic tool

Seasonal Variation in Children's Physical Activity and Sedentary Time.

PURPOSE: Understanding seasonal variation in physical activity is important for informing public health surveillance and intervention design. The aim of the current study was to describe seasonal variation in children's objectively measured physical activity and sedentary time. METHODS: Data are from the UK Millennium Cohort Study. Participants were invited to wear an accelerometer for 7 d on five occasions between November 2008 and January 2010. Outcome variables were sedentary time (2241 counts per minute, min·d(-1)). The season was characterized using a categorical variable (spring, summer, autumn, or winter) and a continuous function of day of the year. Cross-classified linear regression models were used to estimate the association of each of these constructs with the outcome variables. Modification of the seasonal variation by sex, weight status, urban/rural location, parental income, and day of the week (weekday/weekend) was examined using interaction terms in regression models. RESULTS: At least one wave of valid accelerometer data was obtained from 704 participants (47% male; baseline age, 7.6 (0.3) yr). MVPA was lower in autumn and winter relative to spring, with the magnitude of this difference varying by weekday/weekend, sex, weight status, urban/rural location, and family income (P for interaction <0.05 in all cases). Total sedentary time was greater in autumn and winter compared with spring; the seasonal effect was stronger during the weekend than during the weekday (P for interaction <0.01). CONCLUSIONS: Lower levels of MVPA and elevated sedentary time support the implementation of intervention programs during autumn and winter. Evidence of greater seasonal variation in weekend behavior and among certain sociodemographic subgroups highlights targets for tailored intervention programs.The co-operation of the participating families is gratefully acknowledged. The fourth sweep of the Millennium Cohort Study was funded by grants to Professor Health Joshi, former director of the study, from the Economic and Social Research Council and a consortium of government funders. The current director is Professor Lucinda Platt. The authors acknowledge: the Centre for Longitudinal Studies, Institute of Education for the use of these data; the UK Data Service for making them available; the MRC Centre of Epidemiology for Child Health (Grant reference G0400546), Institute of Child Health, University College London for creating the accelerometer data resource which was funded by the Wellcome Trust (grant reference 084686/Z/08/A). The institutions and funders acknowledged bear no responsibility for the analysis or interpretation of these data. The work of Andrew J Atkin, Flo Harrison, and Esther M F van Sluijs was supported, wholly or in part, by the Centre for Diet and Activity Research (CEDAR), a UKCRC Public Health Research Centre of Excellence (RES-590-28-0002). Funding from the British Heart Foundation, Department of Health, Economic and Social Research Council, Medical Research Council, and the Wellcome Trust, under the auspices of the UK Clinical Research Collaboration, is gratefully acknowledged. The work of Soren Brage, Stephen Sharp and Esther MF van Sluijs was supported by the Medical Research Council (MC_UU_12015/7, MC_UU_12015/3, MC_UU_12015/1).This is the final version of the article. It first appeared from Wolters Kluwer via http://dx.doi.org/10.1249/MSS.000000000000078

Debate:should we use variable adjusted life displays (VLAD) to identify variations in performance in general surgery?

BACKGROUND: The recent push for the publication of individual surgeon outcomes underpins public interest in safer surgery. Conventional, retrospective assessment of surgical performance without continuous monitoring may lead to delays in identifying poor performance or recognition of practices that lead to be better than expected performance. DISCUSSION: The variable life adjusted display (VLAD) is not new, yet is not widely utilised in General Surgery. Its construction is simple and if caveats are appreciated the interpretation is straightforward, allowing for continuous surveillance of surgical performance. SUMMARY: While limitations in the detection of variations in performance are appreciated, the VLAD could represent a more useful tool for monitoring performance