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Physiological and biomechanical factors of cycling performance
The two primary predictors of cycling performance are maximal oxygen consumption and lactate threshold. However, several physiological and biomechanical factors influence these variables. The purpose of study one was to investigate relative joint contribution, muscle activation, and muscle oxygenation differences between high (HLT) and low (LLT) lactate threshold cyclists with similar maximal oxygen consumption capabilities (VO [subscript 2max]). While there were no differences in muscle oxygenation, the HLT group had greater relative hip contribution at 90% of VO [subscript 2max] compared to the LLT group, as well as decreased vastus medialis EMG activation during exercise at 60 and 70% of VO [ subscript 2max] (p0.05). The improvement in VO [subscript 2peak-cycling] was accompanied by a 6.3 ± 2.5% increase (Pre: 228 ± 18 W vs. Post: 242 ± 19 W) in peak work rate achieved during post-testing in the training group (p<0.05). This suggests that VO [subscript 2peak-cycling] can be increased through maximal power training in non-cyclists likely as a result of increased ability to recruit additional muscle mass during intense cycling exercise. Taken together, these studies indicate that biomechanical muscle recruitment 'strategies' can influence both submaximal (i.e. LT [subscript VO2]) and peak oxygen consumption (i.e. VO [subscript 2peak-cycling]) during cycling.Kinesiology and Health Educatio
A Data Trust for Industry Data Sharing
This document is an extract from the report Building a Trusted Framework for Coordinating OA Monograph Usage Data, which forms part of the Andrew W. Mellon Foundation funded project, Understanding OA Ebook Usage: Toward a Common Framework
Association Between Early Hyperoxia Exposure After Resuscitation From Cardiac Arrest and Neurological Disability: Prospective Multicenter Protocol-Directed Cohort Study
BACKGROUND:
Studies examining the association between hyperoxia exposure after resuscitation from cardiac arrest and clinical outcomes have reported conflicting results. Our objective was to test the hypothesis that early postresuscitation hyperoxia is associated with poor neurological outcome.
METHODS:
This was a multicenter prospective cohort study. We included adult patients with cardiac arrest who were mechanically ventilated and received targeted temperature management after return of spontaneous circulation. We excluded patients with cardiac arrest caused by trauma or sepsis. Per protocol, partial pressure of arterial oxygen (Pao2) was measured at 1 and 6 hours after return of spontaneous circulation. Hyperoxia was defined as a Pao2 >300 mm Hg during the initial 6 hours after return of spontaneous circulation. The primary outcome was poor neurological function at hospital discharge, defined as a modified Rankin Scale score >3. Multivariable generalized linear regression with a log link was used to test the association between Pao2 and poor neurological outcome. To assess whether there was an association between other supranormal Pao2 levels and poor neurological outcome, we used other Pao2 cut points to define hyperoxia (ie, 100, 150, 200, 250, 350, 400 mm Hg).
RESULTS:
Of the 280 patients included, 105 (38%) had exposure to hyperoxia. Poor neurological function at hospital discharge occurred in 70% of patients in the entire cohort and in 77% versus 65% among patients with versus without exposure to hyperoxia respectively (absolute risk difference, 12%; 95% confidence interval, 1-23). Hyperoxia was independently associated with poor neurological function (relative risk, 1.23; 95% confidence interval, 1.11-1.35). On multivariable analysis, a 1-hour-longer duration of hyperoxia exposure was associated with a 3% increase in risk of poor neurological outcome (relative risk, 1.03; 95% confidence interval, 1.02-1.05). We found that the association with poor neurological outcome began at ≥300 mm Hg.
CONCLUSIONS:
Early hyperoxia exposure after resuscitation from cardiac arrest was independently associated with poor neurological function at hospital discharge
Innovative interstellar explorer
An interstellar "precursor" mission has been under discussion in the scientific community for at least 30 years. Fundamental scientific questions about the interaction of the Sun with the interstellar medium can only be answered with in situ measurements that such a mission can provide. The Innovative Interstellar Explorer (IIE) and its use of Radioisotope Electric Propulsion (REP) is being studied under a NASA "Vision Mission" grant. Speed is provided by a combination of a high-energy launch, using current launch vehicle technology, a Jupiter gravity assist, and long-term, low-thrust, continuous acceleration provided by an ion thruster running off electricity provided by advanced radioisotope electric generators. A payload of ten instruments with an aggregate mass of ~35 kg and requiring ~30 W has been carefully chosen to address the compelling science questions. The nominal 20-day launch window opens on 22 October 2014 followed by a Jupiter gravity assist on 5 February 2016. The REP system accelerates the spacecraft to a "burnout" speed of 7.8 AU per year at 104 AU on 13 October 2032 (Voyager 1's current speed is ~3.6 AU/yr). The spacecraft will return at least 500 bits per second from at least 200 AU ~30 years after launch. Additional (backup) launch opportunities occur every 13 months to early 2018. In addition to addressing basic heliospheric science, the mission will ensure continued information on the far-heliospheric galactic cosmic ray population after the Voyagers have fallen silent and as the era of human Mars exploration begins
Books.Files: Preservation of Digital Assets in the Contemporary Publishing Industry (A Report)
The book publishing industry is an important social, cultural, and economic institution whose records deserve to be preserved for the public good. Books.Files was an exploratory project funded in part by The Andrew W. Mellon Foundation aimed at assessing the archival value of digital assets in the contemporary publishing industry for stakeholders in the cultural heritage sector (libraries, archives, and academia) as well as in the industry itself. The report addresses the changing technological and organizational circumstances in the creation and collecting of publishers' archives, with an emphasis on the enumeration of the types and variety of digital assets that may form the primary basis for such archives in the future. It emphasizes the extent to which every book published (not just ebooks as such) is in fact "born-digital," and the implications of this shift for future historical and bibliographical scholarship. It concludes with a set of recommendations
High-Frequency InAIAs/InGaAs Metal-Insulator-Doped Semiconductor Field-Effect Transistors (MIDFETs) for Telecommunications
Contains an introduction and a report on one research project.Charles S. Draper Laboratories, Inc. Contract DL-H-418488Fujitsu LaboratoriesJoint Services Electronics Program Contract DAAL03-89-C-0001Joint Services Electronics Program Contract DAAL03-92-C-0001Texas Instrument
Metaproteomic evidence of changes in protein expression following a change in electrode potential in a robust biocathode microbiome
Microorganisms that respire electrodes may be exploited for biotechnology applications if key pathways for extracellular electron transfer (EET) can be identified and manipulated through bioengineering. To determine whether expression of proposed Biocathode-MCL EET proteins are changed by modulating electrode potential without disrupting the relative distribution of microbial constituents, metaproteomic and 16S rRNA gene expression analyses were performed after switching from an optimal to suboptimal potential based on an expected decrease in electrode respiration. Five hundred and seventy-nine unique proteins were identified across both potentials, the majority of which were assigned to three previously defined Biocathode-MCL metagenomic clusters: a Marinobacter sp., a member of the family Chromatiaceae, and a Labrenzia sp. Statistical analysis of spectral counts using the Fisher's exact test identified 16 proteins associated with the optimal potential, five of which are predicted electron transfer proteins. The majority of proteins associated with the suboptimal potential were involved in protein turnover/turnover, motility, and membrane transport. Unipept and 16S rRNA gene expression analyses indicated that the taxonomic profile of the microbiome did not change after 52 hours at the suboptimal potential. These findings show that protein expression is sensitive to the electrode potential without inducing shifts in community composition, a feature that may be exploited for engineering Biocathode-MCL
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