206 research outputs found

    Working Towards Justice: How Can Volunteering be Wrong?

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    Remote Sensing of Forest Trends at Mammoth Cave National Park from 2000 to 2011

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    The influence of climate change and other environmental stressors on the health of midlatitude forests is an important, yet understudied topic for resource managers. Using vegetation indices derived from satellite remote sensing, slight changes in photosynthetic activity can be detected at the spatial scales needed for long-term forest monitoring. This study used remote sensing and geographic information systems to track the photosynthetic activity within Mammoth Cave National Park from 2000 to 2011. Relationships are examined between climate variables and the vegetation indices for the forest as a whole and at selected areas within the park

    Foot pressure distributions during walking in African elephants (Loxodonta africana)

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    Elephants, the largest living land mammals, have evolved a specialized foot morphology to help reduce locomotor pressures while supporting their large body mass. Peak pressures that could cause tissue damage are mitigated passively by the anatomy of elephants' feet, yet this mechanism does not seem to work well for some captive animals. This study tests how foot pressures vary among African and Asian elephants from habitats where natural substrates predominate but where foot care protocols differ. Variations in pressure patterns might be related to differences in husbandry, including but not limited to trimming and the substrates that elephants typically stand and move on. Both species' samples exhibited the highest concentration of peak pressures on the lateral digits of their feet (which tend to develop more disease in elephants) and lower pressures around the heel. The trajectories of the foot's centre of pressure were also similar, confirming that when walking at similar speeds, both species load their feet laterally at impact and then shift their weight medially throughout the step until toe-off. Overall, we found evidence of variations in foot pressure patterns that might be attributable to husbandry and other causes, deserving further examination using broader, more comparable samples

    Temporal discrimination: Mechanisms and relevance to adult-onset dystonia

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    Temporal discrimination is the ability to determine that two sequential sensory stimuli are separated in time. For any individual, the temporal discrimination threshold (TDT) is the minimum interval at which paired sequential stimuli are perceived as being asynchronous; this can be assessed, with high test-retest and inter-rater reliability, using a simple psychophysical test. Temporal discrimination is disordered in a number of basal ganglia diseases including adult-onset dystonia, of which the two most common phenotypes are cervical dystonia and blepharospasm. The causes of adult-onset focal dystonia are unknown; genetic, epigenetic, and environmental factors are relevant. Abnormal TDTs in adult-onset dystonia are associated with structural and neurophysiological changes considered to reflect defective inhibitory interneuronal processing within a network which includes the superior colliculus, basal ganglia, and primary somatosensory cortex. It is hypothesized that abnormal temporal discrimination is a mediational endophenotype and, when present in unaffected relatives of patients with adult-onset dystonia, indicates non-manifesting gene carriage. Using the mediational endophenotype concept, etiological factors in adult-onset dystonia may be examined including (i) the role of environmental exposures in disease penetrance and expression; (ii) sexual dimorphism in sex ratios at age of onset; (iii) the pathogenesis of non-motor symptoms of adult-onset dystonia; and (iv) subcortical mechanisms in disease pathogenesis

    Glaciers in the Canadian Columbia Basin, Technical Report

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    The cryosphere - all forms of frozen water on Earth- plays a fundamental role in its climate system. Seasonal snow, mountain glaciers, ice sheets, and sea ice reflect much of the incoming shortwave radiation at high latitudes and in mountainous terrain back to space, helping to regulate the surface temperature of the planet. Accelerating concentrations of greenhouse gases (Solomon et al. 2009) are responsible for late twentieth and early twenty-first century tropospheric warming; this warming in turn drives large-scale changes in the cryosphere, with global implications that include changes in hemispheric circulation (Francis and Vavrus 2012), sea level rise (Gardner et al. 2013) and increased warming through ice-albedo feedbacks

    COVID-19, antibiotics and One Health: a UK environmental risk assessment

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    There is growing interest in the role of secondary bacterial and fungal infections as a cause of increased morbidity and mortality in COVID-19 patients,1 with reports of up to 95% of COVID-19 inpatients being prescribed antibiotics.2 Concerns have been raised over the environmental implications of such a large-scale drug administration3 and statements made about the potential impacts of COVID-19-related antibiotic prescription on antimicrobial resistance (AMR) and other toxicological effects on the environment.4 The UK National Strategy aims for a world in which AMR is effectively contained, controlled and mitigated by 2040.5 Taking a ‘One Health’ approach to effective stewardship in settings such as those being experienced in the current pandemic will be key to minimizing the negative impacts of antibiotic use. A large proportion of some drugs (and metabolites) are excreted by patients into wastewater treatment works (WwTW), leading to release of drug residues into effluent-receiving rivers and coastal waters. Environmental concentrations and impacts will be greatest where drugs are used in high volumes, pass through WwTW largely undegraded and are discharged into rivers with limited dilution
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