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Understanding how species respond to environmental conditions can assist with conservation strategies and harvest management, especially in arctic and boreal regions that are experiencing rapid climate change. Although climatic influences on species distributions have been studied, broad‐scale effects of climate on survival are less well known. We examined the interactive effects of meteorological and remotely sensed environmental variables on survival of Dall's sheep (Ovis dalli dalli) lambs and adults by synthesizing radio‐telemetry data across their range. We used data from 9 studies of adult sheep and 2 studies of lambs that were conducted between 1997 and 2012 at sites spanning the species' range in Alaska, USA, and northwestern Canada. We obtained environmental variables throughout the range of Dall's sheep, including the normalized difference vegetation index (NDVI) from optical remote sensing, freeze‐thaw frequency (FTF) from passive microwave remote sensing, and gridded climate variables such as snow water equivalent, temperature, and precipitation. We used Cox proportional hazard regression to investigate the effects of environmental variables recorded during summer, winter, and the previous winter on annual survival rates of Dall's sheep lambs and adults. Summer NDVI was the most influential environmental factor affecting lamb survival, with improved lamb survival occurring in years with a high maximum NDVI. Also, lamb predation by coyotes (Canis latrans) and golden eagles (Aquila chrysaetos) decreased substantially with increasing NDVI. The previous winter FTF had the strongest effect on adult survival, with decreased survival occurring after winters with high FTF. In addition, these remotely sensed environmental factors interacted with meteorological factors to affect survival, such that effects of winter temperature depended on summer NDVI and winter FTF. Warm winters increased lamb survival only when preceded by summers with high NDVI, and warm winters increased adult survival only when winter FTF was low. Thus, potential benefits of climate warming may be counteracted if wintertime freeze‐thaw events markedly increase. Correlations among environmental variables across sites were low, and regional climate cycles such as the Pacific Decadal Oscillation (PDO) had weak effects, indicating substantial local variability in climatic conditions experienced by Dall's sheep across their range. These findings can help managers anticipate how Dall's sheep populations will respond to changes in local environmental conditions. Our results also highlight the utility of multiple remotely sensed environmental conditions for ungulate management, especially passive microwave products that provide valuable information on winter icing events. © 2020 The Wildlife Society. Survival of Dall's sheep was affected by changes in winter temperatures, frequencies of freeze‐thaw events, and vegetation productivity. The interactive effects of projected changes in these variables might increase lamb survival and decrease adult survival, with net effects on population numbers that may vary substantially across their distribution based on local climate trends.

Richard Hooker is said to have invented Anglicanism in hisOf the Laws of Ecclesiastical Polity, giving character to an Elizabethan “settlement” of religion sadly lacking it. TheLaws is a model of creative response to deeply alarming civil and religious circumstances. It is the major prose work of the English sixteenth century and is important in other ways. Hooker's distinctive sense of law and rich sense of reason are explored here as major elements in his work. The aim is to suggest the enduring interest of theLaws as a whole by pursuing two of its important themes. Of particular current interest is the framework Hooker offers for understanding the sometimes violent entanglements of religion and politics.

This paper highlights ongoing efforts to validate performance, reliability and robustness of GE SiC MOSFETs for Aerospace and Industrial applications. After summarizing ruggedness and reliability testing performed on 1.2kV MOSFETs, two application examples are highlighted. The first demonstrates the 1.2kV device performance in a prototype high frequency 75kW Aviation motor drive. The second highlights the experimental demonstration of a 99% efficient 1.0MW solar inverter using 1.7kV MOSFET modules in a two-level topology switching at 8kHz. Both applications illustrate that SiC advantage is not only in improved performance, but also in significant system cost savings through simplifications in topology, controls, cooling and filtering.

This paper discusses SiC JTE design tradeoffs required to maximize device performance while minimizing consumed die area, fabrication cost and maintaining good reliability. Modeling and experimental results are provided.

Silicon carbide (SiC) device fabrication technology shares many similarities with Si manufacturing, but identifying whether material differences affect cleaning capability is of interest for this growing field. Material parameter differences include diffusion coefficients, surface energy, and chemical bond strength, all of which can play a role in cleaning critical surfaces. This work compares trace surface contamination levels (as measured by TXRF) after 100 mm or 150 mm 4H SiC wafers underwent mercury-probe capacitance voltage (MCV) mapping, to levels after subsequent cleans. Trace levels of metals such as Hg, Fe, and Ni were controllably added during MCV, and it was shown that a variety of cleaning approaches can return the SiC surface to sub-5x1010 atoms/cm2 levels of cleanliness. Where these cleans fit into an integrated device process flow and comparison of cost are discussed.

Bipolar degradation in 4H-SiC thyristors subjected to high current density stress is reported. The thyristor device structure, its fabrication process as well as testing conditions are described. The Electron Beam Induced Current (EBIC) technique was used for defect analysis in testing of both degraded and non-degraded devices. Possible nucleation sites responsible for the generation of observed defects in degraded devices are discussed

This paper presents a study of performance and scalability of 8kV SiC PIN diodes focusing on area-dependent yield and sensitivity to material properties variation. Successfully fabricated 18 and 36 mm2 SiC-PiN diodes exhibited avalanche breakdown above 8 kV and < 5V forward voltage drop at 100 A/cm2 current density. The fast switching operation of these diodes up to ~5 kHz frequency is evidenced by reverse recovery measurements with by double-pulse inductive switching tests. The devices exhibit 0.142 and 0.169 uC/cm2 stored charge at room temperature and 125oC, respectively, when turned-off from Jf = 100A/cm2 to Vr = 2.1 kV. The measured diode breakdown voltage exhibited location and size dependent yield, indicating the necessity of material quality improvements for production.

Doubly-implanted SiC vertical MOSFETs were fabricated displaying a blocking voltage of 4.2kV and a specific on-resistance of 23 mΩ-cm2, on a 4.5mm x 2.25mm device. Design variations on smaller (1.1mm x 1.1mm) devices showed on-resistance as low as 17 mΩ-cm2 with a blocking voltage of 3.3kV. Analysis is presented of the on-resistance and temperature dependence (up to 175ºC), as well as switching performance. Switching tests taken at 1000V and 6A showed turn-on and turn-off transients of approximately 20-40ns.

ABSTRACTIndirect interactions among species can strongly influence population dynamics and community structure but are often overlooked in management of large mammals. We estimated survival of Dall's sheep (Ovis dalli) in the central Alaska Range, USA, during years of differing snowshoe hare (Lepus americanus) abundance to test whether indirect interactions with a cyclic hare population affect Dall's sheep either negatively, by subsidizing predators (apparent competition), or positively, by diverting predation (apparent commensalism). Annual survival of adult female sheep was consistently high (0.85 for all yr and age classes combined). In contrast, annual estimates of lamb survival ranged from 0.15 to 0.63. The main predators of lambs were coyotes (Canis latrans) and golden eagles (Aquila chrysaetos), which rely on hares as their primary food and prey on lambs secondarily. Coyotes and eagles killed 78% of 65 radiocollared lambs for which cause of death was known. Lamb survival was negatively related to hare abundance during the previous year, and lamb survival rates more than doubled when hare abundance declined, supporting the hypothesis of predator-mediated apparent competition between hares and sheep. However, stage-specific predation and delays in predator responses to changes in hare numbers led to a positive relationship between abundance of adult Dall's sheep and hares. Lacking reliable estimates of survival, a manager might erroneously conclude that hares benefit sheep. Thus, support for different indirect effects can be obtained from different types of data, which demonstrates the need to determine the mechanisms that create indirect interactions. Long-term survey data suggest that predation by coyotes is limiting this sheep population below levels typical when coyotes were rare or absent. Understanding the nature of indirect interactions is necessary to effectively manage complex predator–prey communities.

Due to the Silicon Carbide (SiC) material’s high electric field strength, wide bandgap, and good thermal conductivity, 4H-SiC thyristors are attractive candidates for pulsed power applications. With a thinner blocking layer almost an order of magnitude smaller than its Silicon (Si) counterpart, these devices promise very fast turn-on capabilities as full conductivity modulation occurs >10 times faster than comparable silicon thyristors, low leakage currents at high junction temperatures and at high voltage, and much lower forward voltage drop at high pulse currents. Our progress on the development of large area (4mm x 4mm) SiC thyristors is presented in this paper.

Faecal genotyping has been proposed as a method to examine the diets of individuals, but this application has been virtually unexplored by wildlife biologists. We used faecal genotyping and conventional scat analysis to determine the diets of 42 coyotes Canis latrans belonging to nine social groups in Alaska. We use rarefaction to examine the effect of scat sample size on the accuracy and precision of individual diets, and we simulate diets from scats to determine how diet richness and evenness affect sample size requirements. We then demonstrate the utility of this technique by examining variation in diet among individual coyotes and social groups in relation to prey availability. Estimates of diet diversity and composition were highly variable when <10 scats were used to construct the diet. Diets simulated with a uniform (i.e. even) distribution of prey items required generally smaller sample sizes to estimate diet diversity and richness than diets with exponentially distributed items; however, items in actual scats were exponentially distributed. We found moderate dietary variability among individuals in our study area, and diet overlap was higher among coyotes within social groups than between groups. As predicted by optimal foraging theory, the niche widths of all coyote groups expanded as their primary prey (the snowshoe hare Lepus americanus) became scarce during our three-year study. Despite increased niche width, diet overlap among groups remained constant, suggesting that coyotes selected differing alternative prey. Spatiotemporal variation in snowshoe hare availability explained 70% of the variation in hare consumption among groups, indicating that variation in local prey availability may be the primary cause of diet variation among coyotes. Although faecal genotyping can be used to address ecological questions at the individual level, studies should be designed specifically for this purpose so that sufficient numbers of faeces can be obtained.

In the process of developing high voltage (1500V) SiC power DIMOSFETs, both channel mobility and gate reliability were investigated. Using a MOS-gated Hall structure, the sheet carrier concentration and electron mobility were measured versus gate bias at various temperatures. The Hall mobility increases with increasing temperature, indicating that Coulombic scattering limits the inversion-layer mobility in these SiC MOSFETs at these fields. The gate oxide reliability of thermally-grown oxides on SiC has been characterized by time-dependent dielectric breakdown (TDDB) measurements of MOS capacitors, lateral MOSFETs, and vertical DIMOSFETs fabricated on 4H-SiC. Simple MOS CV dots demonstrate the potential for >10^6 hours lifetime for a gate oxide field < 4MV/cm. However, fully processed lateral or vertical MOSFET devices demonstrated distinctly lower predicted lifetimes and even different failure modes.

We investigated habitat selection patterns of the great bustard Otis tardain a dynamic agricultural landscape in southern Portugal. Combining data from 26 bustard counts with habitat mapping, we used resource selection functions to characterise habitat selection in two areas with different agricultural uses. Selection patterns were compared among areas, seasons (breeding, post-breeding and winter), and flock types (male, female and mixed) during the breeding season. Seasonal differences in selection patterns generally parallelled changes in estimated food availability. Stubbles (i.e. recently harvested fields) and stream margins were preferentially selected by all bustards during the post-breeding period, whereas cereal and fallow fields were selected during winter. During the breeding season, males selected fallow fields more than other habitat types, whereas females selected cereal fields. Habitat selection seemed to be influenced by habitat availability, with birds showing stronger selection for preferred habitats in the areas where they were less available. Great bustards used different habitat types throughout the agricultural year, and we recommend that habitat management promotes a rotational crop system that includes cereal and fallow fields.

This investigation has resulted in an analytical method for the quantitative determination of total lanthanide concentration in aqueous solution by absorbance at 240 nm in the ultraviolet followed by quantitative determination of individual lanthanide ion concentrations by the use of concentration-responsive absorption peaks in the 190–235 nm region. The 240-nm peak is present and is proportional to concentration regardless of the ligand employed to complex the lanthanides (including H2O). The individual lanthanide/ligand peaks in the 190–235 nm region were selected on the basis of their separation from one another, their linearity of absorbance vs. concentration, and their statistical reliability based on replicate sample analyses. Lanthanides involved in this investigation were La+3, Nd+3, Eu+3, Ho+3, and Yb+3. Ligands ultimately selected for complexation were citrate for La+3, Nd+3, and Ho+3, and DTPA for Eu+3, Ho+3, and Yb+3. When large amounts of heavy metal ions were present, a modified method was developed with citrate as the only complexing ligand for all five lanthanides. The method here developed permits the analyses of lanthanide ions in aqueous solution without prior separation and involves the use of comparatively inexpensive instrumentation (UV absorption spectrophotometer).

The part of Hooker’s Of the Laws of Ecclesiastical Politymost attractively relevant to the theme of this conference is Book V, the first spiritually constructive exposition of the religion of the Book of Common Prayer. Hooker’s edifying account of the public duties of religion in the first seventy-five chapters of Book V and of the ordained ministry in the concluding six chapters can readily be appreciated today on its merits, leaving aside the fact that the religion of the Prayer Book was legally prescribed for all English Christians when Hooker wrote. It is on this currently unattractive fact of legal prescription that I want to concentrate, however, for it sets the historical context for the public devotional theology of Book V. To understand Hooker’s justificatory account of this fact is to become clearer about an essential difference between what is going on today when people minister and are ministered to in accordance with Anglican religious forms and what Hooker, at least, held to be going on when these forms were used in the sixteenth century.

Oscar W. Clyatt, Jr., Bulgaria's Quest For Security After The Cold War; McNair Papers Number 15; 106 pages; Available by writing to the Institute for National Strategic Studies, National Defense University, Washington, DC, 20319-6000.Major General (Retd.) Dr Gustav Däniker, Switzerland, 'Wende Golfkrieg -Vom Wesen und Gebrauch Künftiger Streitkräfte'; (Turning-point Gulf War -Structure and Employment of Future Armed Forces), Huber Verlag Frauenfeld, 1992.Schmidt, Peter (ed.) In the Midst of Change: On the Development of West European Security and Defence Cooperation (Nomos Verlagsgesellschaft, Baden-Baden, 1992.

Most activity of adult fishers (Martes pennanti) occurred shortly before sunrise and after sunset, but some activity occurred throughout the day and night. Males and females showed similar amounts of activity, and both were active more frequently in summer than winter. Movements of males were greatest during the spring breeding season; nonreproductive females moved similar distances during all seasons. Eleven maternal dens were in tree cavities; the denning period lasted 8–12 weeks from March through May. The maximum annual parturition rate among females ≥2 years old was 75% (n = 4). This was less than pregnancy rates indicated by corpora lutea, and suggested that some pregnancies were unsuccessful. We hypothesize that delayed implantation allows mating to occur at a favorable time for adults, and births to occur when offspring have the maximum time for development before winter.