Publications by authors named "Toal K"

Pasture tracks are a modern equine housing trend often implemented as a weight control strategy due to the belief that they promote movement, though this is not proven experimentally. To test movement of horses housed in pasture tracks as compared to conventional pasture housing, two experiments were performed using a track (0.2ha, 3.

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Although the role of host movement in shaping infectious disease dynamics is widely acknowledged, methodological separation between animal movement and disease ecology has prevented researchers from leveraging empirical insights from movement data to advance landscape scale understanding of infectious disease risk. To address this knowledge gap, we examine how movement behaviour and resource utilization by white-tailed deer (Odocoileus virginianus) determines blacklegged tick (Ixodes scapularis) distribution, which depend on deer for dispersal in a highly fragmented New York City borough. Multi-scale hierarchical resource selection analysis and movement modelling provide insight into how deer's movements contribute to the risk landscape for human exposure to the Lyme disease vector-I.

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COVID-19 lockdowns in early 2020 reduced human mobility, providing an opportunity to disentangle its effects on animals from those of landscape modifications. Using GPS data, we compared movements and road avoidance of 2300 terrestrial mammals (43 species) during the lockdowns to the same period in 2019. Individual responses were variable with no change in average movements or road avoidance behavior, likely due to variable lockdown conditions.

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There is mounting evidence of SARS-CoV-2 spillover from humans into many domestic, companion, and wild animal species. Research indicates that humans have infected white-tailed deer, and that deer-to-deer transmission has occurred, indicating that deer could be a wildlife reservoir and a source of novel SARS-CoV-2 variants. We examined the hypothesis that the Omicron variant is actively and asymptomatically infecting the free-ranging deer of New York City.

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Unlabelled: White-tailed deer ( ) are highly susceptible to infection by SARS-CoV-2, with multiple reports of widespread spillover of virus from humans to free-living deer. While the recently emerged SARS-CoV-2 B.1.

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Mice have emerged as important models of auditory perception and acoustic communication. To study and model complex sound perception and communication, basic hearing abilities have to be established, yet intensity difference limens have not been measured in CBA/CaJ mice. Nine mice were trained using operant conditioning procedures with positive reinforcement to discriminate sound intensity across frequencies.

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The cannabinoid receptor 1 (CB1R) is found at several stages in the auditory pathway, but its role in hearing is unknown. Hearing abilities were measured in CB1R knockout mice and compared to those of wild-type mice. Operant conditioning and the psychophysical Method of Constant Stimuli were used to measure audiograms, gap detection thresholds, and frequency difference limens in trained mice using the same methods and stimuli as in previous experiments.

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A comparison of allograft and autograft (pulmonary) replacement of the aortic valve has, to our knowledge, not been done in America. Fifty-seven patients (age range, 2 to 70 years; mean age, 30 years) underwent 59 operations for replacement of the aortic valve (20) or entire left ventricular outflow tract (39) using autograft (35) or allograft (24) valves. Many had undergone a previous operation (25) or had concomitant procedures (13).

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The pulmonary artery responses in the isolated whole-blood perfused canine lung to ionized calcium ([Ca++]) were quantified over a range of hypercalcemia and hypocalcemia values ([Ca++] = 0.23-1.88 mM) under conditions of controlled pulmonary blood flow and constant mean aortic and left atrial pressures.

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Two consecutive groups of high risk patients with left main coronary disease (greater than 50% stenosis) undergoing aortocoronary bypass grafting using different cardioplegia delivery methods were compared retrospectively for perioperative myocardial infarction (MI) and mortality. Group I (July 1979 to June 30, 1982, n = 53) received an initial 1000 ml aortic root cardioplegia infusion from a pressure regulated (85-100 mmHg) delivery system. Regional mid-myocardial wall temperatures determined the distal anastomoses sequence (with the warmest region bypassed first) followed by additional 400 ml cardioplegia infusions.

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To examine the relationship between intramyocardial pH during global ischemic arrest and subsequent functional and biochemical recovery, 40 canine hearts were subjected to 4 hours of arrest at 10 degrees C. Four groups, each containing 10 hearts, were differentiated by the oxygen concentration of a hyperkalemic crystalloid cardioplegic solution (CCS), which was infused every 20 minutes. In group 1 the CCS was equilibrated at 4 degrees C with nitrogen to remove oxygen.

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We compared multidose crystalloid hyperkalemic cardioplegic solutions with and without added red cells in 24 canine hearts subjected to 5 hr of arrest at 10 degrees C. All cardioplegic solutions were fully oxygenated at 4 degrees C before delivery. Since blood cardioplegia contained Ca++ carried over with the red cells, Ca++ was added to the crystalloid solution in one group.

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The effect of preoperative aortocoronary bypass grafting on the operative mortality of patients undergoing elective abdominal aortic reconstruction was examined by reviewing a series of 224 consecutive patients (1980 to 1983) (Group I) in whom selective preoperative noninvasive and invasive cardiac screening was used to identify patients with significant coronary stenoses. One patient died during cardiac catheterization. Twenty-seven patients (12 percent) underwent aortocoronary bypass grafting with one operative death (3.

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