4,186 research outputs found
Some consequences of intense electromagnetic wave injection into space plasmas
The future possibility of actively testing the current understanding of how energetic particles may be accelerated in space or dumped from the radiation belts using intense electromagnetic energy from ground based antennas is discussed. The ground source of radiation is merely a convenience. A space station source for radiation that does not have to pass through the atmosphere and lower ionosphere, is an attractive alternative. The text is divided into two main sections addressing the possibilities of: (1) accelerating electrons to fill selected flux tubes above the Kennel-Petscheck limit for stably trapped fluxes, and (2) using an Alfven maser to cause rapid depletion of energetic protons or electrons from the radiation belts
A simulation model of time-dependent plasma-spacecraft interactions
A plasma simulation code is presented that models the time-dependent plasma properties in the vicinity of a spherical, charged spacecraft. After showing agreement with analytic, steady-state theories and ATS-6 satellite data, the following three problems are treated: (1) transient pulses from photoemission at various emission temperatures and ambient plasma conditions, (2) spacecharge limited emission, and (3) simulated plasma oscillations in the long wavelength limit
Terminal Moraine Remnants of the Trail Creek Glacier Northeast of Sun Valley, Idaho
This optional excursion is 8 miles on paved road from the center of Ketchum (Main Street and Sun Valley Road traffic light), northeast through Sun Valley along the Trail Creek Road (fig. 1). A short walk of 10 minutes takes you to the crests of two moraines of very different ages. Here we view and discuss calcareous soils developed into the deposits, the pretty weathering-rinds developed on the sandstone cobbles, and ages of Pinedale and Bull Lake advances. During the Quaternary, an extensive system of mountain glaciers accumulated in the Pioneer and Boulder Mountains and flowed down valleys emanating from the ranges (Evenson and others, 1982, Pearce and others, 1988). An ice field several miles across accumulated in the Trail Creek Summit area and contributed ice to both the northeast-flowing Summit Creek glacier and to south-flowing Trail Creek glacier (fig. 2). Despite barroom talk in Sun Valley and Ketchum, we find no evidence that the resort towns or the Mt. Baldy ski hill were glaciated during the last ice ages. Rather, the glacier of closest approach was the Trail Creek glacier that advanced down valley to about elevation 1,950 m (6,400 ft), where Wilson Creek flows into Trail Creek, about 10 km (6 mi) northeast of the Sun Valley Inn. The remnants of the two terminal moraines are best seen on the spur at the confluence of Wilson Creek and Trail Creek (fig. 3). From the road, facing northeast, the moraines appear as low ridges sloping 12º from the walls of Trail Creek Canyon down to Wilson Creek Canyon. Crest of the upper moraine stands 55 m higher than the lower moraine. The 12º crestal slope down into Wilson Creek, and low position in the valley indicate that this was the terminus of the two glacial advances. Furthermore, only outwash sand and gravel terraces occur below this area; no till or erratics are observed on the canyon walls down valley
California Narcotic Rehabilitation: De Facto Prison for Addicts
This note discusses the history and status of California\u27s statutory plans for coping with the narcotic addiction problem
Observing without acting: a balance of excitation and suppression in the human corticospinal pathway
Transcranial magnetic stimulation (TMS) studies of human primary motor cortex (M1) indicate an increase corticospinal excitability during the observation of another's action. This appears to be somewhat at odds with recordings of pyramidal tract neurons in primate M1 showing that there is a balance of increased and decreased activity across the population. TMS is known to recruit a mixed population of cortical neurons, and so one explanation for previous results is that TMS tends to recruit those excitatory output neurons whose activity is increased during action observation. Here we took advantage of the directional sensitivity of TMS to recruit different subsets of M1 neurons and probed whether they responded differentially to action observation in a manner consistent with the balanced change in activity in primates. At the group level we did not observe the expected increase in corticospinal excitability for either TMS current direction during the observation of a precision grip movement. Instead, we observed substantial inter-individual variability ranging from strong facilitation to strong suppression of corticospinal excitability that was similar across both current directions. Thus, we found no evidence of any differential changes in the excitability of distinct M1 neuronal populations during action observation. The most notable change in corticospinal excitability at the group level was a general increase, across muscles and current directions, when participants went from a baseline state outside the task to a baseline state within the actual observation task. We attribute this to arousal- or attention-related processes, which appear to have a similar effect on the different corticospinal pathways targeted by different TMS current directions. Finally, this rather non-specific increase in corticospinal excitability suggests care should be taken when selecting a "baseline" state against which to compare changes during action observation
Searching for "monogenic diabetes" in dogs using a candidate gene approach
BACKGROUND: Canine diabetes is a common endocrine disorder with an estimated breed-related prevalence ranging from 0.005% to 1.5% in pet dogs. Increased prevalence in some breeds suggests that diabetes in dogs is influenced by genetic factors and similarities between canine and human diabetes phenotypes suggest that the same genes might be associated with disease susceptibility in both species. Between 1-5% of human diabetes cases result from mutations in a single gene, including maturity onset diabetes of the adult (MODY) and neonatal diabetes mellitus (NDM). It is not clear whether monogenic forms of diabetes exist within some dog breeds. Identification of forms of canine monogenic diabetes could help to resolve the heterogeneity of the condition and lead to development of breed-specific genetic tests for diabetes susceptibility. RESULTS: Seventeen dog breeds were screened for single nucleotide polymorphisms (SNPs) in eighteen genes that have been associated with human MODY/NDM. Six SNP associations were found from five genes, with one gene (ZFP57) being associated in two different breeds. CONCLUSIONS: Some of the genes that have been associated with susceptibility to MODY and NDM in humans appear to also be associated with canine diabetes, although the limited number of associations identified in this study indicates canine diabetes is a heterogeneous condition and is most likely to be a polygenic trait in most dog breeds. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/2052-6687-1-8) contains supplementary material, which is available to authorized users
Accounting Department Chairpersons Perceptions Of Business School Performance Using A Market Orientation Model
This manuscript is part of a stream of continuing research examining market orientation within higher education and its potential impact on organizational performance. The organizations researched are business schools and the data collected came from chairpersons of accounting departments of AACSB member business schools. We use a reworded Narver and Slater (1990) market orientation scale and the Jaworski and Kohlis (1993) overall performance scale for use in the current research. 101 chairs of accounting departments whose schools are members of AACSB responded to the survey. The manuscript details the data collection and analysis processes, the statistical findings, along with implications and a call for additional subject matter research
Market Orientation Effects On Business School Performance: Views From Inside And Outside The Business School
In the world of higher education, organizational strategies may take the form of a research, teaching, student-centered, comprehensive, or international strategy, just to name a few. This manuscript reports the results of a national survey examining the possible impacts of employing a market orientation strategy within schools of business and its possible impact on organizational performance. The schools researched are member business schools of the Association to Advance Collegiate Schools of Business (AACSB-International) and all of the schools studied are located in the United States. The respondents to the survey are academic vice-presidents (outsiders) and deans (insiders) of colleges and universities holding membership in AACSB. The academic vice-presidents were chosen as they are thought to hold the outside management position that can primarily affect the organizational strategy of the academic organizations under their purview. The deans of the business schools were selected as they represent the highest inside level of leadership. We use a reworded Narver and Slater (1990) “market orientation” scale and the Jaworski and Kohli’s (1993) “overall performance” scale in the current research. One hundred sixteen academic vice-presidents and 131 business school deans responded to the survey. The manuscript details the data collection and analysis, statistical results, and implications for university leaders of business schools as well as other academic leaders
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