686 research outputs found
ROCKET-BORNE LOW ENERGY ION MEASUREMENTS IN SPACE
A capped hemisphere electrostatic analyzer has been developed for the purpose of performing detailed studies of charged particle distributions in space from sounding rocket platforms. This instrument employs micro channel plate detectors in conjunction with a linear resistive anode to carry out angular imaging, by resistive charge division, of particle arrivals. Two such instruments, capable of supplying 64 x 32 angle-energy positive ion distributions every second were flown on two separate high latitude sounding rockets in February, 1985, from Sondre Stromfjord, Greenland. One of these two rockets featured an active ion beam experiment whereby 200 eV/q Ar\sp{+} ions were injected into the ionospheric plasma from a separated sub payload in broad (\sim60\sp\circ FWHM) beams directed alternately either parallel to or perpendicular to the geomagnetic field. Ion fluxes associated with beam operations were observed on the main payload out to a main/sub payload separation distance of nearly 1 km. Several distinct ion populations are identified, based on their energy/pitch angle characteristics and the existence of ion fluxes at unexpected energies and pitch angles is demonstrated and discussed in light of current understanding of these types of beam-plasma systems. The ion flux signatures of parallel versus perpendicular beam injections are compared and contrasted
Global shifts in the policing of mental health
This special edition outlines the changing landscape
of policing and mental health and provides
readers with an introduction to a multitude of
policy and practice innovations from the UK,
the Netherlands, Canada, the USA, and Brazil.
These examples of innovative and evolving practice
address the challenge of fair, effective, and
equitable responses to people suffering mental
health crises. The special edition takes, as its starting
point, a presumption that knowledge of
mental ill health within policing, as elsewhere, is
limited. This is not to state that there is little
discussion about mental health and policing. On
the contrary, mental health is subject to much
discussion at the policy level but there remains
a gap between policy noise and consistent actionable
change. The articles that follow thus represent
an attempt to enhance and expand the
research agenda in this area and to build an evidence-
base to inform future decision-making
using global and multidisciplinary perspectives
from police officers, health workers, policymakers,
and academics
Multiple attribute scenarios, bounded probabilities, and threats of nuclear theft
A method is presented for developing descriptions of future scenarios and using expert judgment to assess bounds on the probabilities of these scenarios. Multiple attributes are used to describe the important features of the scenarios, and the scenarios are defined as collections of different possible levels of the attributes. Experts assess either numerical values or bounds on various unconditional and conditional probabilities for different attribute levels. These are used to establish constraints for a series of linear programs which are solved to determine the highest and lowest possible probabilities for each scenario. An application is presented to the assessment of potential threats against nuclear material safeguards systems.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/23794/1/0000032.pd
Introduction; An Overview: Energy and Policy
Includes an introduction to the theme of the journal issue and an overview of the problem. Introduction: This issue of Carolina planning focuses on energy. The magazine's coverage includes a number of policy alternatives pertinent to state, local, and national decision-makers in their deliberation over the energy problem. To provide some background information, the periodical begins with a short look at energy patterns and the institutional arrangements presently existing in North Carolina to manage resources. Next, an article and comment discusses national and state strategies for combatting a future petroleum crisis like the 1973 Arab oil embargo. Then, the benefits of a peak load pricing scheme are explained and proposed for North Carolina utilities. Following, are three articles on two widely discussed alternative energy forms: the Liquid Metal Fast Breeder Reactor and solar energy. The magazine concludes with an elaboration on energy conservation and the special role local governments might play in the effort. This collection, we feel, provides a broadly-based, yet in-depth assessment of important aspects of the state's and nation's energy problems, from the point of view of the planner, government official, and citizen. An Overview: Over the past three decades, North Carolina, like the rest of the nation, has seen a spectacular rise in the consumption of energy. What are the major forms of energy use in North Carolina? Basically, the state's power comes from four sources: electricity (which is generated from coal, nuclear, hydroelectric, and fuel oil power), natural gas, gasoline, and fuel oil. How do the trends for each source measure up, and what plans are being made for management of the state's energy resources? The following description presents a brief overview of the existing situation, in terms of demand and supply of existing resources, and their management, in order to provide background information for this energy issue
Downstream high-speed plasma jet generation as a direct consequence of shock reformation
Shocks are one of nature's most powerful particle accelerators and have been connected to relativistic electron acceleration and cosmic rays. Upstream shock observations include wave generation, wave-particle interactions and magnetic compressive structures, while at the shock and downstream, particle acceleration, magnetic reconnection and plasma jets can be observed. Here, using Magnetospheric Multiscale (MMS) we show in-situ evidence of high-speed downstream flows (jets) generated at the Earth's bow shock as a direct consequence of shock reformation. Jets are observed downstream due to a combined effect of upstream plasma wave evolution and an ongoing reformation cycle of the bow shock. This generation process can also be applicable to planetary and astrophysical plasmas where collisionless shocks are commonly found. Several mechanisms exist for formation of jets observed in Earth's magnetosheath. Here, the authors show evidence of high-speed downstream flows generated at the Earth's bow shock as a direct consequence of shock reformation, which is different than the proposed mechanisms.Peer reviewe
Electronic monitoring for improved accountability in western Pacific tuna longline fisheries
The collection of accurate fisheries catch data is critical to ensuring sustainable management of tuna fisheries, mitigating their environmental impacts and for managing transboundary fish stocks. These challenges are exemplified by the western Pacific tuna longline fishery, who's management includes >26 nations, but is informed by critically low coverage of fishing activities by scientific observers. The gap in observer data could be filled by electronic monitoring (EM), but there are few trials that span multiple nations. A large-scale trial of EM systems on tuna longliners based in Palau, Federated States of Micronesia and the Republic of the Marshall Islands, is reported on. Comparisons are made of catch rates of market and bycatch species in corresponding EM, logbook and human observer data. Retained species were under-reported in logbooks by up to three times and discards of many species were not reported in logbooks. Discards identified in the EM data included threatened species such as marine turtles. Catch rate estimates from EM data were comparable to those estimated by human observers. EM data recorded a higher species diversity of catches than logbook data. Analysis of the EM data indicated clusters of bycatch that were associated with specific fishing practices. These results suggest further expansion of EM could inform improved management of both target and bycatch species. Ultimately greater coverage of EM data could contribute to reconciling debates in international stock allocation schemes and support actions to reduce the impacts of the fishery on threatened bycatch species
Repetitive arm functional tasks after stroke (RAFTAS): a pilot randomised controlled trial
Background
Repetitive functional task practise (RFTP) is a promising treatment to improve upper limb recovery following stroke. We report the findings of a study to determine the feasibility of a multi-centre randomised controlled trial to evaluate this intervention.
Methods
A pilot randomised controlled trial was conducted. Patients with new reduced upper limb function were recruited within 14 days of acute stroke from three stroke units in North East England. Participants were randomised to receive a four week upper limb RFTP therapy programme consisting of goal setting, independent activity practise, and twice weekly therapy reviews in addition to usual post stroke rehabilitation, or usual post stroke rehabilitation. The recruitment rate; adherence to the RFTP therapy programme; usual post stroke rehabilitation received; attrition rate; data quality; success of outcome assessor blinding; adverse events; and the views of study participants and therapists about the intervention were recorded.
Results
Fifty five eligible patients were identified, 4-6% of patients screened at each site. Twenty four patients participated in the pilot study. Two of the three study sites met the recruitment target of 1-2 participants per month. The median number of face to face therapy sessions received was 6 [IQR 3-8]. The median number of daily repetitions of activities recorded was 80 [IQR 39-80]. Data about usual post stroke rehabilitation were available for 18/24 (75%). Outcome data were available for 22/24 (92%) at one month and 20/24 (83%) at three months. Outcome assessors were unblinded to participant group allocation for 11/22 (50%) at one month and 6/20 (30%) at three months. Four adverse events were considered serious as they resulted in hospitalisation. None were related to study treatment. Feedback from patients and local NHS therapists about the RFTP programme was mainly positive.
Conclusions
A multi-centre randomised controlled trial to evaluate an upper limb RFTP therapy programme provided early after stroke is feasible and acceptable to patients and therapists, but there are issues which needed to be addressed when designing a Phase III study. A Phase III study will need to monitor and report not only recruitment and attrition but also adherence to the intervention, usual post stroke rehabilitation received, and outcome assessor blinding
The CuSPED Mission: CubeSat for GNSS Sounding of the Ionosphere-Plasmasphere Electron Density
The CubeSat for GNSS Sounding of Ionosphere-Plasmasphere Electron Density (CuSPED) is a 3U CubeSat mission concept that has been developed in response to the NASA Heliophysics program's decadal science goal of the determining of the dynamics and coupling of the Earth's magnetosphere, ionosphere, and atmosphere and their response to solar and terrestrial inputs. The mission was formulated through a collaboration between West Virginia University, Georgia Tech, NASA GSFC and NASA JPL, and features a 3U CubeSat that hosts both a miniaturized space capable Global Navigation Satellite System (GNSS) receiver for topside atmospheric sounding, along with a Thermal Electron Capped Hemispherical Spectrometer (TECHS) for the purpose of in situ electron precipitation measurements. These two complimentary measurement techniques will provide data for the purpose of constraining ionosphere-magnetosphere coupling models and will also enable studies of the local plasma environment and spacecraft charging; a phenomenon which is known to lead to significant errors in the measurement of low-energy, charged species from instruments aboard spacecraft traversing the ionosphere. This paper will provide an overview of the concept including its science motivation and implementation
Validation of the IPAQ Against Different Accelerometer Cut-Points in Older Cancer Survivors and Adults at Risk of Cancer
Introduction: The present study investigated the convergent validity of an interview-administered IPAQ long version (IPAQ-L) in an older population by comparison with objective accelerometry movement data. Methods: Data from 52 participants (mean age 67.9 years, 62% male) were included in the analysis. Treadmill derived (TM-ACC: 1952-5724 cpm) and free-living physical activity (PA) derived (FL-ACC: 760-5724 cpm) accelerometer cut-points were used as criterion. Results: IPAQ-L measures (total PA, leisure-time, walking-time, sedentary time) were significantly correlated with accelerometry (P≤0.05). Differences in sex were observed. Bland-Altman Limits of Agreement analysis showed that the IPAQ-L overestimated PA in relation to accelerometry. Conclusions: Our results show that an interview-administered IPAQ-L shows low to moderate convergent validity with objective PA measures in this population but there may be differences between males and females which should be further investigated
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