5,070 research outputs found

    Nonprofit governance: Improving performance in troubled economic times

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    Nonprofit management is currently pressured to perform effectively in a weak economy. Yet, nonprofit governance continues to suffer from unclear conceptions of the division of labor between board of directors and executive directors. This online survey of 114 executive directors aims to provide clarification and recommendations for social administration

    Dynamic validation of the Planck/LFI thermal model

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    The Low Frequency Instrument (LFI) is an array of cryogenically cooled radiometers on board the Planck satellite, designed to measure the temperature and polarization anisotropies of the cosmic microwave backgrond (CMB) at 30, 44 and 70 GHz. The thermal requirements of the LFI, and in particular the stringent limits to acceptable thermal fluctuations in the 20 K focal plane, are a critical element to achieve the instrument scientific performance. Thermal tests were carried out as part of the on-ground calibration campaign at various stages of instrument integration. In this paper we describe the results and analysis of the tests on the LFI flight model (FM) performed at Thales Laboratories in Milan (Italy) during 2006, with the purpose of experimentally sampling the thermal transfer functions and consequently validating the numerical thermal model describing the dynamic response of the LFI focal plane. This model has been used extensively to assess the ability of LFI to achieve its scientific goals: its validation is therefore extremely important in the context of the Planck mission. Our analysis shows that the measured thermal properties of the instrument show a thermal damping level better than predicted, therefore further reducing the expected systematic effect induced in the LFI maps. We then propose an explanation of the increased damping in terms of non-ideal thermal contacts.Comment: Planck LFI technical papers published by JINST: http://www.iop.org/EJ/journal/-page=extra.proc5/1748-022

    Physical Conditions in the Ionized Gas of 30 Doradus

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    We present a mid-infrared spectroscopic data cube of the central part of 30 Doradus, observed with Spitzer's IRS and MIPS/SED mode. Aromatic dust emission features and emission lines from molecular and atomic hydrogen are detected but not particularly strong. The dominant spectral features are emission lines from moderately ionized species of argon, neon, and sulphur, which are used to determine the physical conditions in the ionized gas. The ionized gas excitation shows strong variations on parsec scales, some of which can plausibly be associated with individual hot stars. We fit the ionic line strengths with photoionization and shock models, and find that photoionization dominates in the region. The ionization parameter U traces the rim of the central bubble, as well as highlighting isolated sources of ionization, and at least one quiescent clump. The hardness of the ionizing radiation field T_rad reveals several "hot spots" that are either the result of individual very hot stars or trace the propagation of the diffuse ionizing field through the surrounding neutral cloud. Consistent with other measurements of giant molecular hydrogen regions, log(U) ranges between -3 and -0.75, and T_rad between 30000 and 85000K.Comment: 32 pages, 26 figures, ApJ accepted. A version with high-resolution images can be found at http://www.astro.virginia.edu/~ged3j/indebetouw20090125.pd

    Internet penetration and consumption inequality in China

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    Growing research shows that information technology accelerates economic growth and development, but the effect of Internet penetration on inequality is less well documented, especially about consumption inequality. On the one hand, Internet lowers transaction costs and offers equal access to online products especially beneficial for remote and poor populations, seemingly reducing inequality. On the other hand, uneven access to the Internet may increase divergences. This study examines the relationship between Internet penetration and consumption inequality. Using data from 155 counties available from 2010 to 2016 China Family Panel Studies, this study examines whether Internet penetration potentially impacts consumption inequality considering regional heterogeneity. Based on fixed‐effect models and the two‐stage least squares regressions, results suggest the Internet penetration may increase consumption inequality measured by the Gini index. Furthermore, higher education and over a certain Internet penetration rate buffer the positive impact of the Internet. In some cases, the Internet has smaller positive or even negative impacts on consumption inequality in regions with higher education levels and over threshold penetrations

    Investigation of mechanical losses of thin silicon flexures at low temperatures

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    The investigation of the mechanical loss of different silicon flexures in a temperature region from 5 to 300 K is presented. The flexures have been prepared by different fabrication techniques. A lowest mechanical loss of 3×1083\times10^{-8} was observed for a 130 μ\mum thick flexure at around 10 K. While the mechanical loss follows the thermoelastic predictions down to 50 K a difference can be observed at lower temperatures for different surface treatments. This surface loss will be limiting for all applications using silicon based oscillators at low temperatures. The extraction of a surface loss parameter using different results from our measurements and other references is presented. We focused on structures that are relevant for gravitational wave detectors. The surface loss parameter αs\alpha_s = 0.5 pm was obtained. This reveals that the surface loss of silicon is significantly lower than the surface loss of fused silica.Comment: 16 pages, 7 figure

    The European Consultation-Liaison Workgroup (ECLW) Collaborative Study. I. General outline.

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    Previous C-L psychiatric service research is seriously limited by its parochial nature; very few results can be generalized outside of the hospital in which the original study was performed because of differences in the nature of the hospital and the type of C-L service. This article presents the general outline and methodology of a European multicentered C-L service delivery study effected by the European Consultation-Liaison Workgroup for General Hospital Psychiatry and Psychosomatics (ECLW). The study is unique in its kind as it allows the comparison of very different C-L services; for example, some services are run by C-L psychiatrists, others are run by C-L psychosomaticists and the study encompasses a large variety of different settings. As a result, both common factors in C-L service delivery and specific local patterns can be explored. The overall hypothesis tested in this study was that the most developed services would see (as well as more patients) a wider variety of clinical problems than small services. The implication is that the absence of well-developed C-L services in a general hospital may mean that there are patients with unmet mental health needs. In separate articles the training and reliability testing of the new Patient Registration Form (PRF) and the Institutional and Provider characteristics will be described. The former includes the use of ICD-10 in the general hospital setting. This study is a collaborative effort made by 226 consultants from 56 psychiatric C-L services in 11 countries. Each consultant recorded details of 1 year's caseload leading to a thorough description of 14,717 patients collected between 1991 and 1993. The advanced methodology included a multicentered international approach, rigid training for all participating consultants, and the development and testing of new instruments. This will allow us to assess the impact of important structural and process variables on the outcome of C-L service delivery in several European countries. These results will be reported in papers both in the international and national literature of the participating countries

    Systematic review of antiepileptic drugs’ safety and effectiveness in feline epilepsy

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    Understanding the efficacy and safety profile of antiepileptic drugs (AEDs) in feline epilepsy is a crucial consideration for managing this important brain disease. However, there is a lack of information about the treatment of feline epilepsy and therefore a systematic review was constructed to assess current evidence for the AEDs’ efficacy and tolerability in cats. The methods and materials of our former systematic reviews in canine epilepsy were mostly mirrored for the current systematic review in cats. Databases of PubMed, CAB Direct and Google scholar were searched to detect peer-reviewed studies reporting efficacy and/or adverse effects of AEDs in cats. The studies were assessed with regards to their quality of evidence, i.e. study design, study population, diagnostic criteria and overall risk of bias and the outcome measures reported, i.e. prevalence and 95% confidence interval of the successful and affected population in each study and in total

    The burden of neglected tropical diseases in Ethiopia, and opportunities for integrated control and elimination

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    Background: Neglected tropical diseases (NTDs) are a group of chronic parasitic diseases and related conditions that are the most common diseases among the 2·7 billion people globally living on less than US$2 per day. In response to the growing challenge of NTDs, Ethiopia is preparing to launch a NTD Master Plan. The purpose of this review is to underscore the burden of NTDs in Ethiopia, highlight the state of current interventions, and suggest ways forward. Results: This review indicates that NTDs are significant public health problems in Ethiopia. From the analysis reported here, Ethiopia stands out for having the largest number of NTD cases following Nigeria and the Democratic Republic of Congo. Ethiopia is estimated to have the highest burden of trachoma, podoconiosis and cutaneous leishmaniasis in sub-Saharan Africa (SSA), the second highest burden in terms of ascariasis, leprosy and visceral leishmaniasis, and the third highest burden of hookworm. Infections such as schistosomiasis, trichuriasis, lymphatic filariasis and rabies are also common. A third of Ethiopians are infected with ascariasis, one quarter is infected with trichuriasis and one in eight Ethiopians lives with hookworm or is infected with trachoma. However, despite these high burdens of infection, the control of most NTDs in Ethiopia is in its infancy. In terms of NTD control achievements, Ethiopia reached the leprosy elimination target of 1 case/10,000 population in 1999. No cases of human African trypanosomiasis have been reported since 1984. Guinea worm eradication is in its final phase. The Onchocerciasis Control Program has been making steady progress since 2001. A national blindness survey was conducted in 2006 and the trachoma program has kicked off in some regions. Lymphatic Filariasis, podoconiosis and rabies mapping are underway. Conclusion: Ethiopia bears a significant burden of NTDs compared to other SSA countries. To achieve success in integrated control of NTDs, integrated mapping, rapid scale up of interventions and operational research into co implementation of intervention packages will be crucial
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