789 research outputs found
Cosmogenic nuclides in cometary materials: Implications for rate of mass loss and exposure history
As planned, the Rosetta mission will return to earth with a 10-kg core and a 1-kg surface sample from a comet. The selection of a comet with low current activity will maximize the chance of obtaining material altered as little as possible. Current temperature and level of activity, however, may not reliably indicate previous values. Fortunately, from measurements of the cosmogenic nuclide contents of cometary material, one may estimate a rate of mass loss in the past and perhaps learn something about the exposure history of the comet. Perhaps the simplest way to estimate the rate of mass loss is to compare the total inventories of several long-lived cosmogenic radionuclides with the values expected on the basis of model calculations. Although model calculations have become steadily more reliable, application to bodies with the composition of comets will require some extension beyond the normal range of use. In particular, the influence of light elements on the secondary particle cascade will need study, in part through laboratory irradiations of volatile-rich materials. In the analysis of cometary data, it would be valuable to test calculations against measurements of short-lived isotopes
Occurrence of extreme solar particle events: Assessment from historical proxy data
The probability of occurrence of extreme solar particle events (SPEs) with
the fluence of (>30 MeV) protons F30>10^{10} cm^{-2} is evaluated based on data
of cosmogenic isotopes 14C and 10Be in terrestrial archives
centennial-millennial time scales. Four potential candidates with
F30=(1-1.5)x10^{10} cm^{-2} and no events with F30>2x10^{10} cm^{-2} are
identified since 1400 AD in the annually resolved 10Be data. A strong SPE
related to the Carrington flare of 1859 AD is not supported by the data. For
the last 11400 years, 19 SPE candidates with F30=(1-3)x10^{10} cm^{-2} are
found and clearly no event with F30>5x10^{10} cm^{-2} (50-fold the SPE of
23-Feb-1956) occurring. This values serve as an observational upper limit for
the strength of SPE on the time scale of tens of millennia. Two events, ca. 780
and 1460 AD, appear in different data series making them strong candidates to
extreme SPEs. We built a distribution of the occurrence probability of extreme
SPEs, providing a new strict observational constraint. Practical limits can be
set as F30~1x, 2-3x, and 5x10^{10} cm^{-2} for the occurrence probability
~10^{-2}, 10^{-3} and 10^{-4} year^{-1}, respectively. Because of
uncertainties, our results should be interpreted as a conservative upper limit
of the SPE occurrence near Earth. The mean SEP flux is evaluated as ~40 (cm2
sec)^{-1} in agreement with estimates from the lunar rocks. On average, extreme
SPEs contribute about 10% to the total SEP fluence.Comment: accepted to Astrophys.
Success and limiting factors in health service innovation: a theory generating mixed-methods evaluation of UK projects
Objectives: To explore and explain success and limiting factors in UK health service innovation. Design: Mixed methods evaluation of a series of health service innovations involving a survey and interviews, with theory-generating analysis. Setting: The research explored innovations supported by one of the UK’s Academic Health Science Networks which provides small grants, awards and structural support to health service innovators including clinical academics, health and social care professionals and third-sector organisations. Participants: All recipients of funding or support 2014–2018 were invited to participate. We analysed survey responses relating to 56 innovation projects. Results: Responses were used to conceptualise success along two axes: value creation for the intended beneficiaries and expansion beyond its original pilot. An analysis of variance between categories of success indicated that participation, motivation and evaluation were critical to value generation; organisational, educational and administrative support were critical to expansion; and leadership and collaborative expertise were critical to both value creation and expansion. Additional limiting factors derived from qualitative responses included difficulties navigating the boundaries and intersections between organisations, professions, sectors and cultures; a lack of support for innovation beyond the start-up phase; a lack of protected time; and staff burn-out and turnover. Conclusions: A nested hierarchy of innovation needs has been derived via an analysis of these factors, providing targeted suggestions to enhance the success of future innovations. Data availability statement Data are available upon reasonable request. Due to the highly individual nature of healthcare innovations and the limited geographic area of this study, we are unable to provide our raw data. We undertake to provide a redacted data set upon reasonable request
Electronic Spectroscopy of He@C60+ for Astrochemical Consideration
The electronic spectrum of the endohedral fullerene He@C+60 observed by messenger spectroscopy in a cryogenic ion trap is presented. The role played by the messanger tag in the adopted experimental method is evaluated by recording spectra of He@C+60 − Hen with n = 1−4. The results indicate a linear shift of ∼ 0.7 Å in the wavelengths allowing accurate gas phase values to be reported. The presence of the helium inside the cage shifts the absorption bands by 2−3 Å toward shorter wavelengths compared to C+60. The magnitude of this displacement will enable searches for the spectral signatures of this fullerene analogue in interstellar environments by absorption spectroscopy. The implications for potential astronomical detection are discussed
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Beyond the clinical team: evaluating the human factors-oriented training of non-clinical professionals working in healthcare contexts
Background: As clinical simulation has evolved, it is increasingly used to educate staff who work in healthcare contexts (e.g. hospital administrators) or frequently encounter clinical populations as part of their work (e.g. police officers) but are not healthcare professionals. This is in recognition of the important role such individuals play in the patients’ experience of healthcare, frequently being a patients’ first point of contact with health services. The aim of the training is to improve the ability of the team to communicate and co-ordinate their actions, but there is no validated instrument to evaluate the human factors learning of non-clinical staff. Our aim was to develop, pilot and evaluate an adapted version of the Human Factors Skills for Healthcare Instrument, for non-clinical professionals.
Method: The 18-item instrument was developed reflecting the human factors skills of situation awareness, decision making, communication, teamwork, leadership, care and compassion and stress and fatigue management. The instrument was piloted pre- and post-training with non-healthcare professionals (n = 188) attending mental health simulation training within an 11-month period (June 2017–April 2018). Trainees were hospital/primary care administrators (n = 53, 28%), police officers (n = 112, 59%), probation officers (n = 13, 7%) and social workers (n = 10, 5%). Most participants were female (n = 110, 59%) and from White ethnic backgrounds (n = 144, 77%).
Results: Six items were removed, five were not sufficiently sensitive to change (d  .7). Cluster analysis revealed that participants with lower pre-training scores showed the greatest improvement.
Discussion: The Human Factors Skills for Healthcare Instrument-Auxiliary version (HuFSHI-A) provides a reliable and valid instrument for the evaluation of human factors skills learning following training of non-clinical populations working in healthcare contexts. Although this instrument has been developed and evaluated with training courses specifically focusing on mental health topics, HuFSHI-A is applicable for any training where teamwork and co-ordination between clinical and non-clinical professionals is considered
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Understanding adaptive teamwork in health care: Progress and future directions
Health care teamwork is a vital part of clinical work and patient care but is poorly understood. Despite poor teamwork being cited as a major contributory factor to adverse events, we lack vital knowledge about how teamwork can be improved. Teams in health care are diverse in structure and purpose, and most patient care depends on the ability of different professionals to coordinate their actions. Research in this area has narrowly defined health care teams, focused mainly on a small range of settings and activities and addressed a limited range of research questions. We argue that a new approach to teamwork research is needed and make three recommendations. First, the temporal and dynamic features of teamwork should be studied to understand how teamwork unfolds sequentially. Second, contextual influences should be integrated into study designs, including the organization of work, tasks, patients, organisational structures, and health care system factors. Finally, exploratory, rather than confirmatory, research designs are needed to analyse the complex patterns of social interaction inherent in health care work, to build our theoretical understanding of health care teams and their work, and ultimately to develop effective interventions to support better teamwork for the benefit of patients
Prevention Of Xerophthalmia By Oral Massive Dose Vitamin A: (A Preliminary Report)
Untuk menilai efektivitas pemberian vitamin A dosis tinggi (200.000 IU vitamin A dan 40 IU vitamin E) secara masai dalam USAha pencegahan xerophthalmia, dilakukan penelitian terhadap seluruh anak umur 1-5 tahun di tujuh RK kotamadya Salatiga dan lima desa kabupaten Semarang, oleh suatu team ophthalmologi.
Pada pemeriksaan awal ditemukan 132 penderita xerophthalmia diantara 2812 anak (4,7 persen). Kepada 2680 anak yang tidak menderita xerophthalmia sebagian diberi kapsul vitamin A dosis tinggi dan sebagian lain diberi kapsul placebo yang identik, secara "double-blind" diperiksa ulang sesudah enam bulan. Ternyata bahwa 7 diantara 1286 anak penerima vitamin A yang diperiksa (0,5 persen) menunjukkan tanda-tanda xerophthalmia. Sedang diantara 1183 anak penerima placebo yang diperiksa ternyata terdapat 43 penderita xerophthalmia (3,6 persen). Secara statistik bedanya amat bermakna. Tanda-tanda utama yang ditemukan adalah kombinasi dari buta-senja, xerosis conjunctiva, dan bercak Bitot. Kedua tanda yang terakhir ini terdapat pada 90 persen dari penderita, sedang buta-senja hanya 15 persen. Pada pemeriksaan ulang 132 anak penderita xerophthalmia yang telah diberi kapsul vitamin A dosis tinggi ternyata bahwa 91 persen dari yang diperiksa tidak lagi memperlihatkan tanda-tanda xerophthalmia. Jumlah anak yang tidak dapat diperiksa kembali jauh dibawah angka perkiraan. Sebagian besar karena telah pindah alamat, sebagian kecil meninggal.
Antara golongan placebo dan vitamin, jumlah anak yang tidak dapat diperiksa kembali ini sama besar.
Penelitian ini membuktikan bahwa kapsul vitamin A dosis tinggi efektip sekali untuk mencegah timbulnya xerophthalmia dan menyembuhkan gejala-gejala xerophthalmia ringan
Interprofessional teamwork for managing medical deterioration in pregnancy: What contributes to good clinical performance in simulated practice?
Objectives: To identify the patterns of teamwork displayed by interprofessional teams during simulated management of medical deterioration in pregnancy and examine whether and how they are related to clinical performance in simulated practice.
Design: Exploratory observational cohort study.
Setting: Interprofessional clinical simulation training with scenarios involving the management of medical deterioration in pregnant women.
Participants: Seventeen simulated scenarios involving 62 qualified healthcare staff working within the National Health Service attending clinical simulation training (midwives (n=18), obstetricians (n=24) and medical physicians (n=20)).
Main outcome measure(s): Teamwork behaviours over time, obtained through detailed observational analysis of recorded scenarios, using the Temporal Observational Analysis of Teamwork (TOAsT) framework. Clinician rated measures of simulated clinical performance.
Results: Scenarios with better simulated clinical performance were characterised by shared leadership between obstetricians and midwives at the start of the scenario, with obstetricians delegating less and midwives disseminating rationale, while both engaged in more information gathering behaviour. Towards the end of the scenario, better simulated clinical performance was associated with dissemination of rationale to the team. More delegation at the start of a scenario was associated with less spontaneous sharing of information and rationale later in the scenario. Teams that shared their thinking at the start of a scenario continued to do so over time.
Conclusions: Teamwork during the opening moments of a clinical situation is critical for simulated clinical performance in the interprofessional management of medical deterioration in pregnancy. Shared leadership and the early development of the shared mental model are associated with better outcomes
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Skin Deep: Highlights of NREL Surface Analysis PV Research
The Surface Analysis project provides measurement support and leadership for collaborative research activities involving surface chemistry and physics in all areas of the PV program. Significant results from the past fiscal year include the following: i) in-situ XPS, UPS, and AES studies of chemical-bath exposure of CIGS surfaces demonstrated that Group-III elements are preferentially removed from the surface, that type conversion of the surface occurs, and that the addition of a surfactant improves CdS deposition and thus device performance; ii) XPS studies of polyethylene terephthalate (PET) candidate backsheet materials have shown that plasma exposure prior to oxide-barrier deposition results in the formation of low-molecular-weight fragments that result in the formation of a weak interfacial layer that fails during damp-heat exposure; iii) an empirical relation was derived for the source geometry that leads to optimal film-thickness uniformity in rotating-substrate physical-vapor deposition (PVD) systems; and iv) PVD flux-distribution calculations were performed to develop a novel method for combinatorial thin-film synthesis
A 4500-year time series of Pacific cod (Gadus macrocephalus) size and abundance: archaeology, oceanic regime shifts, and sustainable fisheries
A 4500-year archaeological record of Pacific cod (Gadus macrocephalus) bones from Sanak Island, Alaska, was used to assess the sustainability of the modern fishery and the effects of this fishery on the size of fish caught. Allometric reconstructions of Pacific cod length for eight
prehistoric time periods indicated that the current size of the nearshore, commercially fished Pacific cod stocks
is statistically unchanged from that of fish caught during 4500 years of subsistence harvesting. This finding
indicates that the current Pacific cod fishery that uses selective harvesting technolog ies is a sustainable
commercial fishery. Variation in relative Pacific cod abundances provides further insights into the response of
this species to punctuated changes in ocean climate (regime shifts) and indicates that Pacific cod stocks can recover from major environmental perturbations. Such palaeofisheries
data can extend the short time-series of fisheries data (<50 yr) that form the basis for fisheries management in
the Gulf of Alaska and place current trends within the context of centennial- or millennial-scale patterns
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