Publications by authors named "R Mackie"

This publication aims to provide guidelines of the knowledge required and the potential research to be conducted in order to understand the mode of action of antimethanogenic feed additives (AMFA). In the first part of the paper, we classify AMFA into 4 categories according to their mode of action: (1) lowering dihydrogen (H) production; (2) inhibiting methanogens; (3) promoting alternative H-incorporating pathways; and (4) oxidizing methane (CH). The second part of the paper presents questions that guide the research to identify the mode of action of an AMFA on the rumen CH production from 5 different perspectives: (1) microbiology; (2) cell and molecular biochemistry; (3) microbial ecology; (4) animal metabolism; and (5) cross-cutting aspects.

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Introduction: Managing cognitive demand is critical for aviation safety. Yet, accurately assessing pilot workload during complex flight maneuvers remains challenging. This study evaluated an integrated methodology combining real-time cognitive engagement indicators to provide a comprehensive assessment and assess the reliability of physiological and subjective measures for monitoring operator state.

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Second-generation biofuel production, which aims to convert lignocellulose to liquid transportation fuels, could be transformative in worldwide energy portfolios. A bottleneck impeding its large-scale deployment is conversion of the target polysaccharides in lignocellulose to their unit sugars for microbial fermentation to the desired fuels. Cellulose and hemicellulose, the two major polysaccharides in lignocellulose, are complex in nature, and their interactions with pectin and lignin further increase their recalcitrance to depolymerization.

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Purpose: To assess the 6-month visual and refractive outcomes of keratorefractive lenticule extraction (KLEx) as compared to laser in situ keratomileusis (LASIK) and photorefractive keratectomy (PRK) in a military population at a Joint Warfighter Refractive Surgery Center.

Setting: Joint Warfighter Refractive Surgery Center (JWRSC), Lackland Air Force Base, San Antonio, TX.

Design: Retrospective Study.

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Introduction: Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation method, popular due to its low cost, ease-of-application, and portability. As such, it has gained traction in examining its potential for cognitive enhancement in a diverse range of populations, including active-duty military. However, current literature presents mixed results regarding its efficacy and limited evaluations of possible undesirable side-effects (such as degradation to cognitive processes).

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