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We designed two practical, user-friendly, low-cost, aesthetically pleasing resources, with the goal of introducing residents and observers to a new Competence by Design assessment system based on entrustable professional activities. They included a set of rotation- and stage-specific entrustable professional activities reference cards for bedside use by residents and observers and a curriculum board to organize the entrustable professional activities reference cards by stages of training based on our program's curriculum map. A survey of 14 emergency medicine residents evaluated the utilization and helpfulness of these resources. They had a positive impact on our program's transition to Competence by Design and could be successfully incorporated into other residency programs to support the introduction of entrustable professional activities-based Competence by Design assessment systems.
Parasite distribution patterns in lotic catchments are driven by the combined influences of unidirectional water flow and the mobility of the most mobile host. However, the importance of such drivers in catchments dominated by lentic habitats are poorly understood. We examined parasite populations of Arctic charr Salvelinus alpinus from a series of linear-connected lakes in northern Norway to assess the generality of lotic-derived catchment-scale parasite assemblage patterns. Our results demonstrated that the abundance of most parasite taxa increased from the upper to lower catchment. Allogenic taxa (piscivorous birds as final host) were present throughout the entire catchment, whereas their autogenic counterparts (charr as final hosts) demonstrated restricted distributions, thus supporting the theory that the mobility of the most mobile host determines taxa-specific parasite distribution patterns. Overall, catchment-wide parasite abundance and distribution patterns in this lentic-dominated system were in accordance with those reported for lotic systems. Additionally, our study highlighted that upper catchment regions may be inadequate reservoirs to facilitate recolonization of parasite communities in the event of downstream environmental perturbations.
Invertebrates are of particular interest on heather moorlands because of their rapid response to small scale habitat changes. Spiders constitute a variable proportion of the diet of heather moorland bird, mammal and reptile species. Furthermore, spiders may be an important indicator of habitat change resulting from management practices, especially those that exert a large- scale spatial impact, e.g. grazing. The component families and species of spider assemblages indicate, through their differing preference for web attachments and web structure, the vegetation density, height and structure (Marc et al., 1999). This effect may be especially pronounced where continued grazing at a particular stocking rate results in characteristic patterns in the vegetation structure. Species and family specific hunting strategies determine prey type and so the presence of some spider species may indicate the presence of a preferred prey species. This study aims to investigate the effect of grazing with sheep alone or in combination with cattle grazing on an upland heather moorland in the north of England.
To achieve their conservation goals individuals, communities and organizations need to acquire a diversity of skills, knowledge and information (i.e. capacity). Despite current efforts to build and maintain appropriate levels of conservation capacity, it has been recognized that there will need to be a significant scaling-up of these activities in sub-Saharan Africa. This is because of the rapid increase in the number and extent of environmental problems in the region. We present a range of socio-economic contexts relevant to four key areas of African conservation capacity building: protected area management, community engagement, effective leadership, and professional e-learning. Under these core themes, 39 specific recommendations are presented. These were derived from multi-stakeholder workshop discussions at an international conference held in Nairobi, Kenya, in 2015. At the meeting 185 delegates (practitioners, scientists, community groups and government agencies) represented 105 organizations from 24 African nations and eight non-African nations. The 39 recommendations constituted six broad types of suggested action: (1) the development of new methods, (2) the provision of capacity building resources (e.g. information or data), (3) the communication of ideas or examples of successful initiatives, (4) the implementation of new research or gap analyses, (5) the establishment of new structures within and between organizations, and (6) the development of new partnerships. A number of cross-cutting issues also emerged from the discussions: the need for a greater sense of urgency in developing capacity building activities; the need to develop novel capacity building methodologies; and the need to move away from one-size-fits-all approaches.
A method of estimating siding velocity is presented. It rests on few assumptions, one of which is that longitudinal strain-rate varies linearly with depth. The flow law of ice is not used. To apply it, the sliding velocity at one point must be known. The method is used to calculate the sliding velocity at twelve points on Athabasca Glacier. These values are not related to calculated basal shear stresses. Thus one or more of the following statements must be true: (1) basal shear stress cannot be calculated by the conventional formula, (2) the roughness of the glacier bed varies from place to place, (3) sliding velocity does not obey Weertman's formula. Analysis of seven published measurements of sliding velocity leads to the same conclusion.
Accumulation on the Meighen Ice Cap appears to be about normal for the region, but ablation seems abnormally low. Statistical analyses of several years’ data reveal the following trends: accumulation increases towards the north; ablation decreases with increase of elevation, decreases towards the north and west, and is greater on south-facing slopes than elsewhere. Because ice movement is very small, these trends explain the surface topography of the ice cap quite well. Other topics discussed are the significance of changes in the margins of a stagnant ice cap, and the rate at which net mass balance changes with elevation.
Closely spaced measurements of diameter of thermally drilled bore holes reveal a pattern of small variations. These patterns serve to igerntify points on the bore-hole wall; thus the change in length of sections of bore hole can be gertermined as a function of time. This method has been used to measure vertical strain-rate as a function of gerpth in two bore holes near the crest of the Devon Island ice cap. The measured strain-rate, corrected for firn compaction, varies significantly with gerpth. The vertical component of velocity at the surface was gertermined freom the contraction rate of a bore hole that penetrated to the base of the ice. Comparison of this velocity with the present accumulation rate suggests that the ice cap, in the vicinity of the bore hole, is thickening slightly at present. The age of the ice at various gerpths, as calculated freom the measured vertical velocities, is in broad agreement with radio-carbon dates covering the past 6 000 years. This suggests that the flow of the ice cap has not varied significantly over this period, and thus that the present accumulation rate, which is causing thickening, is slightly above the average for the period.
A comparison has been mager between ice velocities that were measured by the radio-echo technique and by a survey method on the Devon Island ice cap, Arctic Canada (lat. 75° 23' N., long. 82° 23'W.). Results were 2.58±0.11 ma1 by radar and 2.17±0.20 m a–1 by survey. The discrepancy between the two measurements is within the limits of statistical significance, and the methods are consigerred to give comparable results.
The temperature in the ablation area of Athabasca Glacier is about —0.5°C at a depth of 10 m. Below 17 m the temperature is slightly below the calculated pressure melting point (average difference 0.01 deg) in some places. Heat produced by ice deformation is calculated as a function of depth in two bore holes. Only in about the lower half of the glacier thickness is this heat sufficient to maintain the ice at the observed temperature as the hydrostatic pressure is reduced by ablation. Freezing of water within the ice must provide heat for this purpose elsewhere in the glacier; it must also provide heat to maintain the deeper ice close to the melting point even though the 10 m temperature is negative. The minimum water content needed is estimated to be between 0.5 and 1%. It is argued that most of this water must be water trapped between grains when the ice formed from firn. The small difference from the pressure melting temperature measured below 17 m probably arises either from impurities or because, as a result of heat supplied for pressure-melting of ice around air bubbles, the ice is at the melting point corresponding to the bubble pressure rather than to the hydrostatic pressure.
The physical setting of the Athabasca Glacier is described. Ablation of ice from the glacier contributes roughly 40 per cent of the annual outflow from the lake at the terminus. Variations of ice velocity, measured over periods ranging from a week to four months, are discussed. Few if any of these variations can be explained by changes of ice thickness. Variations in the amount of water at the glacier bed provide a plausible explanation however, and the data lend some support to Weertman’s ideas on this subject. Variations in annual velocity of the glacier are not correlated with stream flow, but passage of a kinematic wave provides an explanation of these variations. The wave is attributed to a climatic change which began about 1938.
Weekly observations were made on the horizontal and vertical components of surface movement of the Sefstrøms Gletscher, north-east Greenland. It is concluded that in the area in question the state of the glacier is consistent with Nye’s concept of extending flow. Melting observations were also made. An estimate of ice thickness, derived from measurements of surface slope, is given.
Ten-meter temperature measurements show that Athabasca Glacier is temperate in the accumulation area but not in the ablation area. An important factor in determining whether all the ice will reach a temperature of 0° C by the end of summer is how much of the layer of ice, cooled during the previous winter, is removed by ablation. However, calculations show that, even when allowance is made for ablation, not enough heat is conducted into the ice to bring it all to the melting point. As recent work suggests that ice at 0° C is permeable to water, latent heat released by refreezing of percolating melt water is considered; it appears likely that this process is an insignificant heat source in the ablation area. Available data show that the penetration of solar radiation can probably also be neglected. The question of how widespread temperate glaciers are is discussed; it is predicted that in most, if not all, glaciers there is a region below the equilibrium line where, because ablation is low, the glacier is not strictly temperate.