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Sanjhai Ramdeen,1 Brandon Ferrell,1 Christopher Bonk,2 Laura Schubel,2 Robin Littlejohn,2 Muge Capan,3 Ryan Arnold,4 Kristen Miller1,2 1Georgetown University School of Medicine, Washington, DC, USA; 2National Center for Human Factors in Healthcare, MedStar Health Research Institute, Washington, DC, USA; 3Decision Sciences & MIS Department, LeBow College of Business, Drexel University, Philadelphia, PA, USA; 4Department of Emergency Medicine, Drexel University School of Medicine, Philadelphia, PA, USACorrespondence: Kristen MillerNational Center for Human Factors in Healthcare, MedStar Health Research Institute, 3007 Tilden Street NW, Suite 6N, Washington, DC, 20008, USATel +1 2022433873Fax +1 8553449800Email Kristen.E.Miller@medstar.netObjective: The goal of the study was to assess the criteria availability of eight sepsis scoring methods within 6 hours of triage in the emergency department (ED).Design: Retrospective data analysis study.Setting: ED of MedStar Washington Hospital Center (MWHC), a 912-bed urban, tertiary hospital.Patients: Adult (age ≥ 18 years) patients presenting to the MWHC ED between June 1, 2017 and May 31, 2018 and admitted with a diagnosis of severe sepsis with or without shock.Main Outcomes Measured: Availability of sepsis scoring criteria of eight different sepsis scoring methods at three time points— 0 Hours (T0), 3 Hours (T1) and 6 Hours (T2) after arrival to the ED.Results: A total of 50 charts were reviewed, which included 23 (46%) males and 27 (54%) females. Forty-eight patients (96%) were Black or African American. Glasgow Coma Scale was available for all 50 patients at T0. Vital signs, except for temperature, were readily available (> 90%) at T0. The majority of laboratory values relevant for sepsis scoring criteria were available (> 90%) at T1, with exception to bilirubin (66%) and creatinine (80%). NEWS, PRESEP and qSOFA had greater than 90% criteria availability at triage. SOFA and SIRS consistently had the least percent of available criteria at all time points in the ED.Conclusion: The availability of patient data at different time points in a patient’s ED visit suggests that different scoring methods could be utilized to assess for sepsis as more patient information becomes available.Keywords: sepsis, scoring systems, available criteria, emergency department, patient safety, quality improvement

To determine the effects of deer antler velvet on maximal aerobic performance and the trainability of muscular strength and endurance, 38 active males were randomly assigned in a double-blind fashion to either deer antler velvet extract (n = 12), powder (n = 13), or placebo groups (n = 13). Subjects were tested prior to beginning supplementation and a 10-week strength program, and immediately post-training. All subjects were measured for circulating levels of testosterone, insulin-like growth factor, erythropoietin, red cell mass, plasma volume, and total blood volume. Additionally, muscular strength, endurance, and VO2max were determined. All groups improved 6 RM strength equivalently (41 +/- 26%, p < .001), but there was a greater increase in isokinetic knee extensor strength (30 +/- 21% vs. 13 +/- 15%, p = .04) and endurance (21 +/- 19% vs. 7 +/- 12%, p = .02) in the powder compared to placebo group. There were no endocrine, red cell mass or VO2max changes in any group. These findings do not support an erythropoetic or aerobic ergogenic effect of deer antler velvet. Further, the inconsistent findings regarding the effects of deer antler velvet powder supplementation on the development of strength suggests that further work is required to test the robustness of the observation that this supplement enhances the strength training response and to ensure this observation is not a type I error. [ABSTRACT FROM AUTHOR]

Considerable expansion of red deer farming has occurred in the South Island high country of New Zealand. On these farms, breeding hinds are usually continuously grazed (set-stocked) at low population densities in large highly modified native-tussock grassland paddocks during their calving and lactation seasons. The present study determined how these hinds use the tussock grassland over this critical period, identifying the most essential resources for them and also some potential long-term consequences of their behaviour on the grassland ecosystem. This was achieved by tracking nine GPS-collared hinds over 2 years on a high-country deer farm in Te Anau, Southland, New Zealand. The home ranges of the GPS-tracked hinds varied widely, occupying between 15% and 52% of the total paddock area. Vegetation dominated by naturalised exotic pasture species covered the greatest proportion (>60%) of eight of nine hind home ranges. In contrast, tussock-dominant vegetation coverage was far more variable (0.4–46%), with several indicators suggesting that this vegetation type was used as a substitute for pasture areas under high intra-specific competition among the deer. Both pasture- and tussock-dominant vegetation was used in proportion to its availability. In contrast, shrub-dominated vegetation was used less than its proportional availability, indicating that it was not being put under as much foraging or grazing pressure. This has implications for the further ingression of this vegetation type over time. There was also clear evidence that certain paddock topography was being favoured by the hinds, namely steeper and higher-altitude areas of a paddock. On the basis of these findings, some potential methods for aiding in the management of these extensive tussock grassland paddocks under deer grazing are suggested. In the South Island high country of New Zealand large tracts of native-tussock grasslands are increasingly being used for red deer farming. The present study used GPS-tracking and GIS technologies to identify the main habitats that red deer use in these tussock-grasslands, the typically daily behavioural patterns of the deer, and the likely long-term consequences of their behaviour on this type of grassland ecosystem. The results of the present study will aid in the future management of this type of grassland under deer farming. [ABSTRACT FROM AUTHOR]

Engineers need considerable understanding of humanities and social science to serve effectively and responsibly as professionals. Undergraduate engineering education faces pressures to add technical and non-technical content and decrease total credit hours, educational costs, and time to degree. This study characterizes how discipline-based engineering programs in the United States distribute required coursework between technical and non-technical areas of study in comparison to math, chemistry, and physics programs; the results could signal consensus or disparity in educational philosophy between and among institutions or disciplines. The distribution of technical versus non-technical coursework was delineated for 103 US News & World Report top-ranked and ABET EAC-accredited undergraduate programs in chemical, civil, electrical, and mechanical engineering based on 2013 catalog requirements, as well as chemistry, math, and physics programs at the same institutions. Technical was defined as coursework in engineering, math or natural science; non-technical was coursework outside of those disciplines. Findings reveal a wide range of required technical and non-technical course loads for all disciplines. For engineering, technical requirements ranged from 62% to 86% (median 75%) of total degree; non-technical requirements ranged from 12% to 35% (median 20%). The math, chemistry, and physics degrees were more balanced between technical and non-technical requirements. Differences in requirements suggest that consensus does not exist amongst engineering educators from this sampling of programs regarding the appropriate allocation of technical versus non-technical coursework for an undergraduate engineering education, and there are substantially divergent interpretations of what constitutes adequate "general education" for an engineer. Additionally, students who desire more well-rounded education might select non-engineering STEM majors. [ABSTRACT FROM AUTHOR]

Agriculture is a major source of phosphorus (P) and suspended sediment (SS) losses to aquatic ecosystems promoting eutrophication. Mechanical soil loosening equipments such as topsoil looseners or aerators have been reported to improve the physical quality and infiltration of soils susceptible to livestock damage resulting from treading. We hypothesized that soil aeration would significantly decrease the volume of surface runoff and consequent losses of P and SS compared with non-aerated soil (control) in cattle-grazed pasture on a poorly structured silt-loam soil. Hydrologically isolated plots (2 m long × 1 m wide × 0.15 m deep) were installed in aerated and control plots to collect surface runoff following irrigation or rainfall and analysed for P and SS losses for 1 year. Soil physical properties [% macroporosity, bulk density, saturated hydraulic conductivity ( Ksat) and unsaturated hydraulic conductivity ( Kunsat at −1kPa)] were measured in the aerated and control treatments and taken before each irrigation event ( n = 12). Six months after mechanical aeration was employed, but before cattle grazing commenced, no significant differences in soil physical quality were found between aerated and control treatments, with the exception of a minor increase in Kunsat for the control plots. This lack of treatment difference continued after grazing and was largely attributed to the re-settling of the poorly structured and dispersive soil. Flow-weighted mean concentrations and annual loads of dissolved reactive P (DRP) on the mechanically aerated soil (2.24 kg DRP/ha) were approximately double those from the control treatment (1.20 kg DRP/ha). However, no significant differences were observed between treatments for surface runoff volumes and losses of total P and total SS, which may reflect the similar soil physical conditions exhibited between treatments throughout most of the trial. As observed elsewhere, time (days) since grazing or fertilizer application was found to influence P and/or SS losses. We conclude that aeration did not decrease P and SS losses. Any changes in soil physical properties such as macroporosity were short-lived and therefore unlikely to influence surface runoff and subsequent P and SS losses for this soil type. [ABSTRACT FROM AUTHOR]

SUMMARY: Land-use intensification requires more farm inputs to sustain or increase farm product outputs. However, a common concern for land-use intensification is the potential deterioration of soil. The North Otago Rolling Downlands (NORD) region of New Zealand is drought prone, and although traditionally limited to extensive sheep farming, there are large-scale conversions to intensive cattle grazing operations such as dairy farming resulting from an irrigation scheme commissioned in 2006. Pallic soils (Aeric Fragiaqualf in US Soil Taxonomy) such as those in the NORD region are prone to soil compaction because of their 'high' structural vulnerability under intensive management. To address these concerns, a field trial was established on a common NORD Pallic soil (Timaru silt loam) to determine how land-use intensification affects indicators of soil quality (macroporosity, bulk density, structural condition score, total and mineralizable carbon and nitrogen and earthworms) and pasture production. The treatments compare irrigated v. dryland pasture and sheep v. cattle grazing on 16 plots. The findings show that soil physical quality responds more quickly to changes in land-use pressure than do biochemical and organic indicators. Both irrigation and cattle grazing, particularly in combination, increased soil compaction; macroporosity on irrigated plots grazed by cattle ranged from 9·1 to 13·3% v/v at a depth of 0–50 mm, compared to dryland plots with sheep grazing (18·9–23·0% v/v). Soil compaction/damage has implications for pasture production, soil hydrology and nutrient movement. Land management practices for intensive cattle grazing of irrigated soil prone to treading damage therefore need to implement high compaction risk strategies to avoid or ameliorate potential changes to soil quality. [ABSTRACT FROM AUTHOR]

Two catchments were used to test the hypothesis that using reactive phosphate rock (RPR), a low water soluble fertilizer, instead of superphosphate, could decrease phosphorus (P) export in streams. The sheep-grazed catchments, each ca. 12 ha in size, received 20–25 kg P/ha either as RPR or superphosphate for 3 yr. Filterable (<0.45 μm) reactive P (FRP) and total P (TP) in stream samples were then compared against two subsequent years when both catchments received 20 kg P/ha as superphosphate. On average, during the 5-yr study, loads of FRP and TP in stream flow were low (110 g FRP/ha and 358 g TP/ha), typical of dry sheep-grazed hill country. However, FRP (58%) and TP (38%) in stream flow were significantly less when RPR was applied instead of superphosphate. Where appropriate climatic and soil conditions exist to maintain agronomic targets, RPR could be used to decrease P export in streams. [ABSTRACT FROM AUTHOR]

Diffuse pollution from grazed pastures is recognised as an important source of faecal microbial contamination of surface waters, and farmers urgently require mitigation options to reduce this impact of their farming activities. An obvious mitigation strategy is to reduce the size of the reservoir of faecal material in pastures during critical periods when overland flow is most likely. This work tested the hypothesis that smearing fresh cowpats to increase their surface area would increase exposure to solar radiation and increase desiccation, which in turn would accelerate the die-off of Escherichia coli in the faecal material. The total solids content and E. coli concentration in intact and disrupted cowpats were monitored during the four seasons. The total solids content was significantly ( P < 0.001) higher in the disrupted cowpats compared to the intact cowpats. This indicates that increased desiccation of the faecal material was successful. However, there was no significant difference ( P > 0.05) in E. coli concentrations in the disrupted and intact cowpats. The physical disruption of cowpats did not therefore accelerate the die-off of E. coli in the faecal material. The disrupted cowpats did appear to decompose faster than the intact cowpats. Mitigation options to reduce faecal micro-organism losses in overland flow from grazed pastures will now need to focus on other methods to reduce the build up of reservoirs of faecal material on farm. [ABSTRACT FROM AUTHOR]

The article reports on the results of research which was conducted to evaluate the physical properties of soil (porosity, bulk density, saturated hydraulic conductivity) of a Pallic soil (Pukemutu silt loam) and pasture production on a dairy farm in Southland, New Zealand, under a number of different cattle grazing strategies: (i) normal grazing management on undrained land, (ii) normal grazing practice on drained land, (iii) restricted autumn grazing, (iv) restricted grazing when soil conditions were wet, (v) never pugged, and (vi) never grazed. Researchers found that there were no significant differences in any soil physical properties measured on cattle grazed treatments. They also determined that spring pasture yield from the never grazed treatment was greater (P < 0.05) than the drained and undrained standard practice grazing treatments for one of the three seasons. Researchers concluded that the never pugged grazing strategy failed to prevent soil compaction by dairy cows and that when soil water content was greater than the plastic limit, the pugged grazing strategy probably contributed to both soil treading damage and compaction during the traditionally wet early spring period.

The North Otago Rolling Downlands (NORD) of New Zealand is currently undergoing a large change in land use with subsequent intensification as a result of a new large community irrigation scheme. To assess the effect of this change, a 4-year monitoring survey was established on two common Pallic soil types of the area to determine the influence of irrigation term (short, <5 years vs. long, >5 years) and grazing animal (cattle vs. sheep) on a range of physical and organic matter soil quality parameters. This 4-year survey also included the historical land use of dryland sheep farming in the absence of irrigation water. Irrigation term had no significant ( P > 0.05) effect on soil physical parameters (percentage macroporosity and bulk density) for 3 of 4 years and no significant effect ( P > 0.05) on topsoil total carbon or nitrogen contents. However, irrigation term had a significant ( P < 0.01) but biologically small effect on the ratio of carbon to nitrogen with narrowing of the range under longer term irrigation. A significant difference between the dryland and irrigated surveys was found for macroporosity (dryland sheep 17.3% v/v vs. irrigated sheep 13.4% v/v; P < 0.001) and for the C:N ratio (dryland sheep 10.7 vs. irrigated sheep 10.2; P < 0.05). The change in macroporosity under irrigation is likely to take effect within 1 or 2 years of land-use change as little discernable differences in soil physical properties were evident from land under short- or long-term irrigation. [ABSTRACT FROM AUTHOR]

The objective of this study was to deter- mine whether differences in mRNA levels of key pituitary genes that regulate GH production, pituitary development, and growth were present and/or associated with divergent body composition phenotypes observed between sheep from genetically divergent lean and fat selection lines. Real-time PCR transcription profiles for pituitary specific transcription factor 1, prophet of pit 1, GH, GH receptor, GH secretagogue receptor, GHRH receptor, leptin receptor, and somatostatin receptors 1 and 2 were determined in pituitary tissue. There was a difference in the amount of both GH (P < 0.001) and GH secretagogue receptor (P < 0.001) mRNA between the selection lines (5 females and 5 males per line; 20 wk of age); the lean line had greater abundance than the fat line, irrespective of which endogenous control gene was used. The results obtained for GHRH receptor were equivocal but suggestive; there were greater GHRH receptor mRNA levels (P < 0.001) in the lean line using beta-2-microglobulin as the endogenous con- trol but not when hypoxanthine phosphoribosyltransferase and glyceraldehyde-3-phosphate dehydrogenase were used. No difference in pituitary specific transcription factor 1, prophet of pit 1, GH receptor, leptin receptor, or somatostatin receptors 1 and 2 mRNA concentration was observed between the lines. The greater abundance of GH mRNA in the pituitary somatotropes from genetically lean animals appears to be associated with increased levels of GH secretagogue receptor mRNA and possibly GHRH receptor mRNA. This suggests that the difference in GH secretion between the lines may be due to differences in the afferent signals, such as ghrelin and/or GHRH, arising from the hypothalamus, or as a result of differential pituitary sensitivity to these hormones. [ABSTRACT FROM AUTHOR]

Coopworth sheep selected for low (lean) or high (fat) backfat have large differences in plasma GH profiles. Fat genotype ram lambs (5 months old) were treated with growth hormone (GH) to simulate the plasma GH profiles of lean sheep and investigate whether exogenous GH could modify carcass fatness. For 77 days, bovine GH was administered at 25 Uglkg live weight per day either as a single, daily subcutaneous bolus (fat bolus) or via portable pulsatile infusion pumps (fat pump) which delivered GH solution at 90-min intervals into a jugular catheter. Measurements of body composition were made by computed tomography (CT) and ultrasonic scanning during the trial, with linear carcass measurements and proximate analysis undertaken at the end of the experiment.Before treatments began, mean plasma GH levels were lower (P < 0·01) in fat control (0·34 ugll) than in lean lambs (1·1 μg/l). Several weeks after the start of the trial, mean plasma GH had increased in both fat bolus (1·2 μg/l) and fat pump (0·45 μg/l) treatment lambs with major changes in the pulsatility relative to the fat control lambs. Although these changes were maintained in the fat bolus lambs, by the end of the trial there was no significant difference in mean plasma GH between fat pump and fat control sheep. Throughout the trial, plasma 1GF-1 levels were higher in fat bolus, fat pump and lean lambs than in fat control lambs. Analysis of body composition data over the GH treatment period revealed that the slope of the allometric equation for total fat relative to empty body weight was lower in the fat bolus lambs (1·07) than in the lean lambs (1·50) with fat control and fat pump treatment lambs intermediate (1·30 and 1·36, respectively). Subcutaneous fat was later maturing in lean lambs than in fat control and bolus treatment lambs when regressed against total fat, with the fat pump treatment lambs being intermediate. Linear carcass measurements revealed changes due to GH administration in the distribution of subcutaneous fat and eye muscle dimensions.It is concluded that sheep from the fat genotype show physiological responses to exogenous GH. Increasing plasma GH levels of fat sheep increased plasma IGF-1 and had variable effects on carcass fatness. The change in body composition may be affected by the mode of administration of exogenous GH. [ABSTRACT FROM PUBLISHER]

In carrying out a nonlocal analysis of drift cyclotron loss cone (DCLC) modes in a cylindrically symmetric plasma, a new dispersion relation branch not described by local theories has been found. The model assumes a low-β plasma column with a Gaussian density profile in a uniform magnetic field. The exact k-space integral equation is solved using a Laguerre polynomial decomposition of the eigenfunctions. It is these new modes that couple with the diamagnetic drift wave to form unstable DCLC modes, a phenomenon not predicted by local theory. The existence of these modes requires a proper treatment of the spatial variation of the equilibrium distribution function describing the ions. [ABSTRACT FROM AUTHOR]

Winter growth of young male red deer can be increased by exposure to 16 h of light (L) and 8 h of dark (D) per day (16L: 8D). This study tested the duration of photoperiod required for this growth response, determined if the time to reach slaughter weight can be reduced and monitored plasma IGF-1, prolactin and reproductive development. Fifty male calves were allocated to five equal groups. Four groups were housed indoors and for 33 weeks from the winter solstice (22 June, southern hemisphere) until 11 February were placed under either 16L: 8D (16L), 13·25L: 10·75D (13L), 10·751:13·25D (111) or 8L: 16D (8L) photoperiods. The fifth group of deer (OC) remained outside in a gravelled enclosure. All groups were given a pelleted diet ad libitum. Group food intake was recorded daily, individual live weight was measured weekly and testes diameter and blood samples taken at weekly or 2-week intervals.Plasma prolactin concentrations in 16L increased within 4 weeks of treatment and were different (P < 0·001) between groups from 14 August to 4 September. IGF-1 increased in both 16L and 13L 4 weeks after treatments and then increased further in 16L above that of 13L (P < 0·01). All groups grew at the same rate for the first 7 weeks. 16L then gained more weight (P < 0·001) than the other groups over the next 19 weeks (50·7 kg v. 38·5 for 13L, 35·7 for 11L, 37·0 for 8L and 37·4 for OC; s.e.d. 3·76). Food intake was positively related to growth rate in a similar way among the inside groups (P < 0·001), however there was a higher energy requirement outdoors (P < 0·05). A target live weight for slaughter of 95 kg was reached 7 weeks earlier for 16L than the other groups (P < 0·01). Testes diameter of 16L was larger than in the other groups from 13 November until 24 December (P < 0·001). The growth oflSL slowed from 1 January while that of OC increased and the live weight ofOC was equal to 16L by the end of the experiment. OC also had the largest testes diameter from 5 February onwards (P < 0·01). The live-weight increase in OC was associated with increases in both prolactin and IGF-1 levels.This study confirmed that 16L: 8D stimulates rapid growth of young male red deer during winter for sufficient time to achieve an earlier slaughter date. The live-weight advantage was lost by late summer however. The increased growth rate was mediated by food intake and associated with increases in IGF-1 and prolactin and earlier reproductive development. Photoperiods of 13 h of light per day or less did not stimulate growth and increases in IGF-1 and prolactin were of a lower amplitude than under 16L: 8D. [ABSTRACT FROM PUBLISHER]

The aim of this study was to determine whether the decrease in plasma growth hormone (GH) levels during a lamb's first autumn is a function of photoperiodic or developmental changes. Wether lambs (no. = 30) from Coopworth sheep selected for low (lean) or high (fat) backfat plus a randomly selected line (control) were subjected to long (16 h light: 8 h dark) or short (8 h light: 16 h dark) photoperiod over a 5-month period after the summer solstice. The animals were regularly blood sampled to determine plasma hormone concentrations. Daily food intake and weekly live weights were measured and the animals were slaughtered at the end of the trial to determine body composition.Food intake and growth rate were greater for sheep on long than on short photoperiod but photoperiod had no major effect on carcass composition. Mean and basal plasma GH, as well as the number and amplitude of pulses, were not affected by photoperiod, however GH secretion decreased from January to May. Plasma levels ofprolactin, insulin-like growth factor 1 (IGF-1), insulin and glucose were greater in animals under long than short photoperiod, while non-esterified fatty acids (NEFA) were unaffected by photoperiod.Lean animals had greater mean and basal plasma GH and increased number and amplitude of pulses compared with fat animals. Prolactin concentrations were also greater in the lean than in the fat sheep, while there were no differences in insulin, glucose and NEFA levels. IGF-1 levels were higher in lean than in fat sheep under long photoperiod but lower under short photoperiod.These results suggest that the decline in plasma GH with increasing age is not affected by photoperiod. While long photoperiod stimulates plasma prolactin and IGF-1 levels as well as intake and growth, the relationship between these parameters is unknown. Hormonal differences between lean and fat genotype sheep are found within the GH axis and prolactin but not within the gonadotropin or insulin axes. [ABSTRACT FROM PUBLISHER]

The growth of male red deer slows during the first winter of life before increasing again during spring. This study aimed to determine if this period of slow growth could be minimized using artificial photoperiods during autumn and winter (10 April (week 1) to 11 September (week 23), southern hemisphere). Four groups of deer (no. = 10) were housed indoors as follows. Two groups were placed on a winter solstice photoperiod (8·5 light (L): 15·5 dark (D)) and given either a natural increase in photoperiod to 11·25L: 12·75D (WSN) or held on 8·5L: 15·5D for 7 weeks followed by an abrupt increase to 11·25L: 12·75D (WSH). One group was exposed to a summer solstice photoperiod of 16L: 8D (SS) and one group exposed to a natural photoperiodic pattern (IC). A fifth group of deer (no. = 10) was maintained outside on a gravelled enclosure under natural changes in photoperiod (OC). All groups were given a diet containing 160 g protein per kg and 11·0 MJ metabolizable energy per kg dry matter (DM) ad libitum. All animals were weighed weekly and group food intake recorded daily. Metatarsal length was measured at weeks 3,17 and 22 from the start of treatments.The major differences occurred between SS and the other groups. After a period of slower growth (weeks 1 to 5, SS = 88 g/day v. 168 g/day other groups, s.e.d. 31·2, P < 0·05), SS grew more rapidly from week 10 (P < 0·01). As a result, SS was heaviest from week 17 (P < 0·05) until the end of the experiment (P < 0·01). The mean growth rate of SS animals from weeks 10 to 23 was 346 g/day compared with 173 g/day (s.e.d. 15·3; P < 0·001) for the other groups. Over the whole experiment, SS animals gained 42·3 kg live weight, compared with 31·1 kg for WSN, 26·6 kg for WSH, 25·1 kg for OC and 23·7 kg for IC (s.e.d. 2·08 kg P < 0·01). The DM intake of SS from week 9 until the end of the experiment averaged 2·04 kg DM per head per day compared with 1·48 (s.e. 0·041) kg DM per head per day for the mean of the other groups. Metatarsal length increased more in SS than the other groups (P < 0·001) between weeks 3 and 17 and was longest in SS at weeks 17 and 22 (P < 0·01). Exposure to a 16L: 8D photoperiod during winter advanced the rapid growth of red deer calves normally associated with spring and summer. This response may be used to advance slaughter dates for venison production. [ABSTRACT FROM PUBLISHER]

The localization of drift and ion cyclotron modes as well as the drift cyclotron instability for both Maxwellian and loss cone ion energy distributions have been studied. The WKB method for integral equations is found to give insight into the mode structure as well as characteristics of the spectrum, and the method will be used to understand recent numerical results of other authors. [ABSTRACT FROM AUTHOR]