Palaeodistribution of pygmy-possums in Tasmania

This work is a contribution towards documenting the fossil distribution of the pygmy possums Cercartetus lepidus and C. nanus (Marsupialia: Burramyidae) in Tasmania. We provide locality data and bibliographic sources for 15 Quaternary fossil sites important for these species (i.e., Beeton Rockshelter on Badger Island, Cave Bay Cave on Hunter Island, Bone Cave, Derwent River Shelter 7, Kutikina Cave, Mackintosh Cave, Main Drain, March Fly Pot, Newdegate Cave, Nunamira, Ouse River Shelter 7, Peramerpar Meethaner, seudocheirus Cave, Warhol, and Warreen Caves on mainland Tasmania). Dates available for these sites span the period 3960 ± 60 to 34,790 ± 510 years ago. We also draw attention to a Late Oligocene fossil locality at Geilston Bay which produced an undescribed Cercartetus-like species. The recorded palaeodistribution of pygmy-possums in Tasmania is widespread, with sites on two offshore islands, and also in the southern, south western, and western areas of mainland Tasmania

Assessing the psychological impact and acceptability of a first-trimester screening test for pre-eclampsia

BACKGROUND: A first-trimester prenatal screening test for pre-eclampsia was launched in 2010. It differs from previously assessed prenatal screening tests. AIMS: (i) To assess the psychological benefits and consequences of providing a first trimester screening test for pre-eclampsia. (ii) To assess the acceptability of the test amongst pregnant women and healthcare professionals. METHODS: A mixed methods approach was taken. Five consecutive studies using primary and secondary data from UK pregnant women and their healthcare providers were conducted: (i) a systematic review, (ii) a qualitative study (pregnant women); (iii) a qualitative study (healthcare professionals); (iv) a case control study; (v) a discrete choice experiment. RESULTS: A first trimester screening test for pre-eclampsia has the potential to positively change health behaviours, but could also decrease self-monitoring. The impact appears to differ depending on whether the woman is concerned with the potential consequences to herself or her fetus. Health professionals are concerned with the clinical utility of the prenatal screening test, and on its potential to medicalise the pregnancy pathway. However, there does not appear to be an association between the amount of technological monitoring and birthplace preference. A discrete choice experiment showed overwhelming support for the introduction of this test. CONCLUSIONS: There is no evidence that this new prenatal screening test will cause harm to pregnant women. Women appear to welcome the additional information it provides. Receiving a positive pre-eclampsia screening test result presents potential opportunities for health-promotion interventions. To make the most of these opportunities, it will be important for clinicians to understand how women perceive and respond to this screening test; the self-regulation model provides a useful framework in which to do this. This work provides a framework for assessing the psychological impacts of the many emerging prenatal screening tests that lack a diagnostic test or risk-reduction intervention

Ways of Coping: Understanding Workplace Stress and Coping Mechanisms for Hospice Nurses

OBJECTIVE: Hospice programs consider nursing their primary source of professional services. Recruitment and retainment of hospice nurses has been a challenge in the last decade due in part to workplace stress. This research seeks to expand the current body of knowledge surrounding the coping process for this group. Additionally, this research explores the availability and adequacy of workplace resources in order to recommend how organizations can assist in the coping process. METHODS: This study included registered and licensed practical nurses. Eligible subjects were invited to participate in focus group sessions. Participants also completed a survey that collected demographic information and assessed coping strategies through the use of the Ways of Coping Questionnaire. Interviews were audio-recorded and transcribed. Content analysis was performed on interview data. Descriptive statistics and bivariate correlations were performed on the quantitative data. RESULTS: Hospice nurses reported that social support, humor and prayer/meditation were the most effective coping mechanisms. The majority of the participants shared that their hospice agencies offered no formal resources to assist them in times of stress. Informal resources emphasized individual efforts at ameliorating stress that offer little to no long-term therapeutic value. Quantitative results supported focus group feedback in regards to most frequently used strategies. Moderate associations were found between hospice nurse experience and planful problem solving and seeking social support. CONCLUSION: Traditional approaches to combat workplace stress have focused solely on individual efforts. Organizations have an opportunity to develop quality workplace resources that consider the person-environment relationship and build upon coping strategies that nurses find most effective. This information challenges organizations to explore and make available beneficial coping resources with their staff. PUBLIC HEALTH SIGNIFICANCE: Hospice nurses have been identified as a high-risk group for burnout and fatigue as a consequence of workplace stress. The results of this study indicate that there are disparate programs across hospice settings to assist nurses in coping with job stress. Further, hospice nurses consider these efforts to be primarily inadequate and ineffective. Future research should focus on identifying standard policies and practices that best protect this group from injury and illness and ensures the longevity of hospice care

Direct evidence for thymic function in adult humans.

The understanding of human thymic function and evaluation of its contribution to T cell homeostasis are matters of great importance. Here we report the development of a novel assay to quantitate the frequency and diversity of recent thymic emigrants (RTEs) in the peripheral blood of humans. Such cells were defined by the presence of T cell receptor (TCR) rearrangement deletion circles (DCs), episomal byproducts of TCR-beta V(D)J rearrangement. DCs were detected in T cells in the thymus, cord blood, and adult peripheral blood. In the peripheral blood of adults aged 22 to 76 years, their frequency was highest in the CD4(+)CD45RA(+) CD62L(+) subpopulation of naive T cells. TCR DCs were also observed in other subpopulations of peripheral blood T cells, including those with the CD4(+)CD45RO(-)CD62L(+) and CD4(+)CD45RO(+)CD62L(+) phenotypes. RTEs were observed to have more than one Vbeta rearrangement, suggesting that replenishment of the repertoire in the adult is at least oligoclonal. These results demonstrate that the normal adult thymus continues to contribute, even in older individuals, a diverse set of new T cells to the peripheral circulation

A link between attentional function, effective eye movements, and driving ability

The misallocation of driver visual attention has been suggested as a major contributing factor to vehicle accidents. One possible reason is that the relatively high cognitive demands of driving limits the ability to efficiently allocate gaze. We present an experiment that explores the relationship between attentional function and visual performance when driving. Drivers performed two variations of a multiple object tracking task targeting aspects of cognition including sustained attention, dual-tasking, covert attention and visuomotor skill. They also drove a number of courses in a driving simulator. Eye movements were recorded throughout. We found that individuals who performed better in the cognitive tasks exhibited more effective eye movement strategies when driving, such as scanning more of the road, and they also exhibited better driving performance. We discuss the potential link between an individual's attentional function, effective eye movements and driving ability. We also discuss the use of a visuomotor task in assessing driving behaviour

X-ray Emission from Extragalactic Jets

This review focuses on the X-ray emission processes of extra-galactic jets on scales resolvable by the sub arcsec resolution of the Chandra X-ray Observatory. It is divided into 4 parts. The introductory chapter reviews the classical problems for jets, as well as those associated directly with the X-ray emission. Throughout this section, we deal with the dualisms of low powered radio sources versus high powered radio galaxies and quasars; synchrotron models versus inverse Compton models; and the distinction between the relativistic plasma responsible for the received radiation and the medium responsible for the transport of energy down the jet. The second part collects the observational and inferred parameters for the currently detected X-ray jets and attempts to put their relative sizes and luminosities in perspective. In part 3, we first give the relevant radio and optical jet characteristics, and then examine the details of the X-ray data and how they can be related to various jet attributes. The last section is devoted to a critique of the two non-thermal emission processes and to prospects for progress in our understanding of jets.Comment: This is a version of a review article to be published (2006 Sep) in the Annual Reviews of Astronomy and Astrophysics, vol. 44, p. 463. 8 of the 12 figures have been removed from the article and are provided as separate jpg files to conserve space. There are 38 pages remaining in the text. Complete postscript and pdf versions are available at: http://hea-www.harvard.edu/~harris/Xjetreview

Insights into the Fallback Path of Best-Effort Hardware Transactional Memory Systems

DOI 10.1007/978-3-319-43659-3Current industry proposals for Hardware Transactional Memory (HTM) focus on best-effort solutions (BE-HTM) where hardware limits are imposed on transactions. These designs may show a significant performance degradation due to high contention scenarios and different hardware and operating system limitations that abort transactions, e.g. cache overflows, hardware and software exceptions, etc. To deal with these events and to ensure forward progress, BE-HTM systems usually provide a software fallback path to execute a lock-based version of the code. In this paper, we propose a hardware implementation of an irrevocability mechanism as an alternative to the software fallback path to gain insight into the hardware improvements that could enhance the execution of such a fallback. Our mechanism anticipates the abort that causes the transaction serialization, and stalls other transactions in the system so that transactional work loss is mini- mized. In addition, we evaluate the main software fallback path approaches and propose the use of ticket locks that hold precise information of the number of transactions waiting to enter the fallback. Thus, the separation of transactional and fallback execution can be achieved in a precise manner. The evaluation is carried out using the Simics/GEMS simulator and the complete range of STAMP transactional suite benchmarks. We obtain significant performance benefits of around twice the speedup and an abort reduction of 50% over the software fallback path for a number of benchmarks.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Observations of ozone and related species in the northeast Pacific during the PHOBEA campaigns 2. Airborne observations

During late March and April of 1999 the University of Wyoming's King Air research aircraft measured atmospheric concentrations of NO, O3, peroxyacetyl nitrate (PAN), CO, CH4, VOCs, aerosols, and J(NO2) off the west coast of the United States. During 14 flights, measurements were made between 39°-48° N latitude, 125°-129° W longitude, and at altitudes from 0-8 km. These flights were part of the Photochemical Ozone Budget of the Eastern North Pacific Atmosphere (PHOBEA) experiment, which included both ground-based and airborne measurements. Flights were scheduled when meteorological conditions minimized the impact of local pollution sources. The resulting measurements were segregated by air mass source region as indicated by back isentropic trajectory analysis. The chemical composition of marine air masses whose 5-day back isentropic trajectories originated north of 40° N latitude or west of 180° W longitude (WNW) differed significantly from marine air masses whose 5-day back isentropic trajectories originated south of 40° N latitude and east of 180° W longitude (SW). Trajectory and chemical analyses indicated that the majority of all encountered air masses, both WNW and SW, likely originated from the northwestern Pacific and have characteristics of emissions from the East Asian continental region. However, air masses with WNW back trajectories contained higher mixing ratios of NO, NOx, O3, PAN, CO, CH4, various VOC pollution tracers, and aerosol number concentration, compared to those air masses with SW back trajectories. Calculations of air mass age using two separate methods, photochemical and back trajectory, are consistent with transport from the northwestern Pacific in 8-10 days for air masses with WNW back trajectories and 16-20 days for air masses with SW back trajectories. Correlations, trajectory analysis, and comparisons with measurements made in the northwestern Pacific during NASA's Pacific Exploritory Mission-West Phase B (PEM-West B) experiment in 1994 are used to investigate the data. These analyses provide evidence that anthropogenically influenced air masses from the northwestern Pacific affect the overall chemical composition of the northeastern Pacific troposphere. Copyright 2001 by the American Geophysical Union

International experience of marine protected areas and their relevance to South Africa

Marine protected areas (MPAs) have become necessary to counter modern threats to marine biodiversity and the sustainability of fisheries. Sensitive habitats, including coral reefs, estuaries and mangroves, have beeneffectively protected in large MPAs, which control resource use. Protection from pollution and physical destruction by fishing gear are important functions of MPAs in tropical and temperate regions. MPAs havebeen used to protect endangered species and to allow population recoveries. The advantages for fishery management include maintenance of spawner biomass, improvement of yield, simplified enforcement,research opportunity, insurance against stock collapse and maintenance of intraspecific genetic diversity. MPAs can be small with narrow, focused objectives, or large with core areas, buffer zones and exploitableareas to provide an integrated management approach. A variety of design considerations, based on ecological, fishery and socio-economic conditions, is presented. Optimal size and spacing have not been extensivelytested and only theoretical arguments guide the choice of how much to protect. The process of establishing an MPA can be initiated by local communities or by governmental authorities. The former has better publicsupport, whereas the latter promises a well planned system of MPAs. Community and industry involvement in the establishment process is essential for the effective functioning of MPAs. Successful MPAs are administered by national programmes and managed according to management plans. Monitoring, communication and enforcement are integral components of MPA management. South Africa is party to a number of international conventions which promote the designation of MPAs. Better protection of the physical marine environment, incorporation of MPAs in fishery management procedures and the management of MPAs are the major areas where South Africa can improve its marine protection