1,948 research outputs found
The intrinsic rate of increase of reindeer and caribou populations in arctic environments
The intrinsic rate of increase of an animal population, rm, is specific to the environment in which it is measured. Previous estimates of maximum growth rates for reindeer and caribou Rangifer tarandus populations were based on introductions to islands with cool oceanic climates. The mean intrinsic rate of increase of 6 populations was 0.26 ranging from 0.21 on St Paul Island in the Bering Sea to 0.29 in the Barff herd on South Georgia. I calculated rm for two Rangifer populations introduced to arctic environments to determine the effect of environmental severity on the intrinsic rate of increase. Reindeer on the Belcher islands increased at rm= 0.28 and caribou on Southampton Island increased at rm = 0.23 (mean = 0.26). The lower primary productivity and longer duration of snow cover in arctic environments did not affect the intrinsic rate of increase
First Report of the Alfalfa Blotch Leafminer (Diptera: Agromyzidae), and Selected Parasites (Hymenoptera: Eulophidae) in Minnesota and Wisconsin, USA
Alfalfa blotch leafminer, Agromyza frontella, has been a serious pest of alfalfa, Medicago sativa, in the northeastern U.S. and in eastern Ontario, Canada. Until recently, the western edge of the A. frontella distribution in the U.S. was limited to eastern Ohio. We document for the first time, the occurrence of A. frontella in Minnesota and Wisconsin. Alfalfa stems damaged by A. frontella, based on adult feeding punctures, obvious blotched leafmining or the presence of larvae, were first found in 3 northern Minnesota counÂties during October, 1994. Infested counties included Lake of the Woods, Cook and Lake, all bordering western Ontario, Canada. In 1995, A. frontella was again found in Cook and Lake counties, where 99-100% of the stems, and 18-35% of the trifoliates/stem, contained larvae or exhibited obvious feeding damage. In 1996, following a more expanded survey, a total of 11 and 5 counties, in Minnesota and Wisconsin, respectively, showed some level of A. frontella feeding damage (stem samples ranged from \u3c5 to 100% infested). Based on additional counties surveyed 11 October, 1996, where A. frontella was not found, we now have a reasonable estimate of the southern edge of the distribution in Minnesota and Wisconsin. A total of 2 and 6 A. frontella adults were identified from sweep-net samples taken from fields with obvious feeding damage during 1995 (Lake Co.) and 1996 (Cook Co,), respectively. Three eulophid (Hymenoptera) parasites were reared from A. frontella-infested alfalfa stems collected during October, 1994 in Cook Co., Minn., including: Diglyphus begini, D. pulchripes, and Diglyphus sp., prob. isaea, all of which are new records. Our hypothesis is that A. frontella moved into Minnesota from Ontario Canada, via alfalfa hay purchased by northern Minnesota growers
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Expanding Universe Illusion
We present a new induced movement illusion from global expansion or contraction in a triangular region filled with rising or falling textures. Objective global expansion or contraction induces lateral movement in the oblique edges of the triangle. The effects may be due to common and relative movements operating within a single texture
Phosphorus management for soybeans in Manitoba
Non-Peer ReviewedVery little research has been conducted to determine the best rate, source, placement, and timing of P fertilizer for modern soybean cultivars grown in the Canadian Prairies. In 2013 and 2014, 18 sites were established in Manitoba to measure the effect of different rates of monoammonium phosphate (0, 20, 40 and 80 lb P2O5/ac) and different fertilizer placements (seed-placed, broadcast, side-banded or mid-row banded) on soybean plant stand and seed yield. Stand reduction was rare and did not occur at typical agronomic rates of 20-40 lb P2O5/ac. However, at 80 lb P2O5/ac, stand reductions occurred at 4 sites, most frequently in medium to coarse textured soils or when wide row spacing and low seed bed utilization increased fertilizer concentration in the seed row. Nevertheless, seed yield was reduced below that of the unfertilized treatment at only 2 of the 4 site-years where there was a stand reduction. In both cases where seed yield was reduced, the high rate of seedrow P reduced the stand to less than 100,000 plants/acre, the traditional replant threshold for soybean. Phosphorus fertilization regardless of soil P level, P rate and P placement did not increase biomass or seed yield at any of the 18 site years. Even in soils with very low soil P levels (as low as 3 ppm Olsen P) soybeans were able to explore the soil in order to take up enough P to produce high yields without responding to P fertilizer rate and placement
Using ultrasound measurements of rump fat to assess nutritional condition of woodland caribou in northern British Columbia, Canada
Body reserves (fat and protein) of cervids are important to the reproductive success of individuals, and therefore may limit productivity of populations. We used a portable ultrasound machine to measure thickness of rump fat for 39 woodland caribou (Rangifer tarandus caribou) captured in the winters (January–February) of 2003 and 2004. We compared thickness of rump fat between pregnant and non-pregnant individuals in the Besa-Prophet drainage of northern British Columbia, Canada. Thirty-eight of the 39 females captured in British Columbia were adults and 34 of the adult caribou were pregnant (89.5 ± 5.1%, x– ± binomial SE). Pregnant individuals had more rump fat (0.60 ± 0.067 cm) than nonpregnant animals (0.20 ± 0.029 cm). Recognizing that deposition and mobilization of fat vary with age and possibly across the winter season, ultrasonography can be used as a non-invasive technique in the field to assist in estimating body fat of caribou
Angular dependence of domain wall resistivity in artificial magnetic domain structures
We exploit the ability to precisely control the magnetic domain structure of
perpendicularly magnetized Pt/Co/Pt trilayers to fabricate artificial domain
wall arrays and study their transport properties. The scaling behaviour of this
model system confirms the intrinsic domain wall origin of the
magnetoresistance, and systematic studies using domains patterned at various
angles to the current flow are excellently described by an angular-dependent
resistivity tensor containing perpendicular and parallel domain wall
resistivities. We find that the latter are fully consistent with Levy-Zhang
theory, which allows us to estimate the ratio of minority to majority spin
carrier resistivities, rho-down/rho-up~5.5, in good agreement with thin film
band structure calculations.Comment: 14 pages, 3 figure
Shubnikov-de Haas oscillations in YBa_2Cu_4O_8
We report the observation of Shubnikov-de Haas oscillations in the underdoped
cuprate superconductor YBaCuO (Y124). For field aligned along the
c-axis, the frequency of the oscillations is T, which corresponds
to % of the total area of the first Brillouin zone. The effective
mass of the quasiparticles on this orbit is measured to be times
the free electron mass. Both the frequency and mass are comparable to those
recently observed for ortho-II YBaCuO (Y123-II). We show that
although small Fermi surface pockets may be expected from band structure
calculations in Y123-II, no such pockets are predicted for Y124. Our results
therefore imply that these small pockets are a generic feature of the copper
oxide plane in underdoped cuprates.Comment: v2: Version of paper accepted for publication in Physical Review
Letters. Only minor changes to the text and reference
Exploring the role of nurses in after-hours telephone services in regional areas; A scoping review
Introduction
The management of patients who need chronic and complex care is a focus of attention internationally, brought about by an increase in chronic conditions, requiring significantly more care over longer periods of time. The increase in chronic conditions has placed pressure on health services, financially and physically, bringing about changes in the way care is delivered, with hospital avoidance and home-based care encouraged. In this environment, nurses play an important role in co-ordinating care across services. This review formed one part of a funded project that explored the nurse navigator role within a proposed 24-hour telephone-call service in one regional area that has a diverse population in terms of cultural identity and geographical location in relation to service access.
Aim
The review reports on the extant literature on the nurse’s role in the provision of afterhours telephone services for patients with chronic and complex conditions. The specific aim was to explore the effectiveness of services for patients in geographically isolated locations.
Methods
The methodological approach to the review followed the Preferred Reporting System for Meta-Analyses (PRISMA) guidelines. A thematic analysis was used to identify themes with chronic care models underpinning analysis.
Results
Three themes were identified; nurse-led decision making; consumer profile; and program outcomes. Each theme was divided into two sub-themes. The two sub-themes for decision making were: the experience of the staff who provided the service and the tool or protocol used. The two sub-themes for consumers profile were; the geographic/demographic identity of the consumers, and consumer satisfaction. The final theme of outcomes describes how the effectiveness of the service is measured, broken into two sub-themes: the economic/workforce outcomes and the consumer outcomes.
Discussion
The provision of an after-hours telephone service, in whatever model used should align with a Chronic Care Model. In this way, after-hours telephone services provided by experienced nurses, supported by ongoing professional development and relevant protocols, form part of the ongoing improvement for chronic and complex care management as a health priority
Understanding in situ ozone production in the summertime through radical observations and modelling studies during the Clean air for London project (ClearfLo)
Measurements of OH, HO2, RO2i (alkene and aromatic-related RO2) and total RO2 radicals taken during the ClearfLo campaign in central London in the summer of 2012 are presented. A photostationary steady-state calculation of OH which considered measured OH reactivity as the OH sink term and the measured OH sources (of which HO2+ NO reaction and HONO photolysis dominated) compared well with the observed levels of OH. Comparison with calculations from a detailed box model utilising the Master Chemical Mechanism v3.2, however, highlighted a substantial discrepancy between radical observations under lower NOx conditions ([NO] 3 ppbv) the box model increasingly underpredicted total [RO2]. The modelled and observed HO2 were in agreement, however, under elevated NO concentrations ranging from 7 to 15 ppbv. The model uncertainty under low NO conditions leads to more ozone production predicted using modelled peroxy radical concentrations ( ≈ 3 ppbv h-1) versus ozone production from peroxy radicals measured ( ≈ 1 ppbv h-1). Conversely, ozone production derived from the predicted peroxy radicals is up to an order of magnitude lower than from the observed peroxy radicals as [NO] increases beyond 7 ppbv due to the model underprediction of RO2 under these conditions
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