35 research outputs found

    HI spectra and column densities toward HVC and IVC probes

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    We show 21-cm line profiles in the direction of stars and extragalactic objects, lying projected on high- and intermediate-velocity clouds (HVCs and IVCs). About half of these are from new data obtained with the Effelsberg 100-m telescope, about a quarter are extracted from the Leiden-Dwingeloo Survey (LDS) and the remaining quarter were observed with other single-dish telescopes. HI column densities were determined for each HVC/IVC. Wakker (2001) (Paper I) uses these in combination with optical and ultraviolet high-resolution measurements to derive abundances. Here, an analysis is given of the difference and ratio of N(HI) as observed with a 9 arcmin versus a 35 arcmin beam. For HVCs and IVCs the ratio N(HI-9 arcmin)/N(HI-35 arcmin) lies in the range 0.2-2.5. For low-velocity gas this ratio ranges from 0.75 to 1.3 (the observed ratio is 0.85-1.4, but it appears that the correction for stray radiation is slightly off). The smaller range for the low-velocity gas may be caused by confusion in the line of sight, so that a low ratio in one component can be compensated by a high ratio in another -- for 11 low-velocity clouds fit by one component the distribution of ratios has a larger dispersion. Comparison with higher angular resolution data is possible for sixteen sightlines. Eight sightlines with HI data at 1 arcmin-2 arcmin resolution show a range of 0.75-1.25 for N(HI-2 arcmin)/N(HI-9 arcmin), while in eight other sightlines N(HI-Ly-alpha)/N(HI-9 arcmin) ranges from 0.74 to 0.98.Comment: To appear in the "Astrophysical Journal Supplement"; 45 pages; degraded figures (astro-ph restriction) - ask for good version

    HIPASS High-Velocity Clouds: Properties of the Compact and Extended Populations

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    A catalog of Southern anomalous-velocity HI clouds at Decl. < +2 deg is presented, based on data from the HI Parkes All-Sky Survey (HIPASS). The improved sensitivity (5sigma: T_B = 0.04 K) and resolution (15.5') of the HIPASS data results in a substantial increase in the number of individual clouds (1956, as well as 41 galaxies) compared to previous surveys. Most high-velocity emission features, HVCs, have a filamentary morphology and are loosely organized into large complexes extending over tens of degrees. In addition, 179 compact and isolated anomalous-velocity objects, CHVCs, are identified based on their size and degree of isolation. 25% of the CHVCs originally classified by Braun & Burton (1999) are reclassified. Both the entire population of high-velocity emission features and the CHVCs alone have typical HI masses of ~ 4.5 D(kpc)^2 solar masses and have similar slopes for their column density and flux distributions. On the other hand, the CHVCs appear to be clustered and the population can be broken up into three spatially distinct groups, while the entire population of clouds is more uniformly distributed with a significant percentage aligned with the Magellanic Stream. The median velocities are V_GSR = -38 km/s for the CHVCs and -30 km/s for all of the anomalous-velocity clouds. Based on the catalog sizes, high-velocity features cover 19% of the southern sky and CHVCs cover 1%. (abridged)Comment: 32 pages, 26 figures in gif format, 2 ascii tables, to appear in the Jan 2002 issue of The Astronomical Journal, high resolution version available at http://origins.Colorado.EDU/~mputman/pubs.htm

    Optical spectroscopy of the M15 intermediate velocity cloud

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    We present echelle spectrograph observations in NaD, at resolutions of 6.2-8.5 km/s, for 11 stars located in the line-of-sight to the M15 intermediate velocity cloud, which has a radial velocity of 70 km/s. This cloud is a part of IVC Complex gp. The targets range in magnitude from V=13.3-14.8. Seven of the observed stars are in the M15 globular cluster, the remaining four being field stars. Column density ratios of log(N cm^-2)=11.8-12.5 are derived. Combining the current sightlines with previously-existing data, we find the NaD/HI ratio in the IVC varies by upto a factor of 25. One cluster star, M15 ZNG-1, was also observed in Calcium. We find N(CaI)/N(CaII)<0.03 and NaI/CaII=0.25, similar to values seen in the local ISM. Finally, we detect tentative evidence for IV absorption in KI towards 3 cluster stars.Comment: A&A, in pres

    The association between palliative care team consultation and hospital costs for patients with advanced cancer: An observational study in 12 Dutch hospitals

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    Background: Early palliative care team consultation has been shown to reduce costs of hospital care. The objective of this study was to investigate the association between palliative care team (PCT) consultation and the content and costs of hospital care in patients with advanced cancer. Material and Methods: A prospective, observational study was conducted in 12 Dutch hospitals.

    Distances and Metallicities of High- and Intermediate-Velocity Clouds

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    A table is presented that summarizes published absorption line measurements for the high- and intermediate velocity clouds (HVCs and IVCs). New values are derived for N(HI) in the direction of observed probes, in order to arrive at reliable abundances and abundance limits (the HI data are described in Paper II). Distances to stellar probes are revisited and calculated consistently, in order to derive distance brackets or limits for many of the clouds, taking care to properly interpret non-detections. The main conclusions are the following. 1) Absolute abundances have been measured using lines of SII, NI and OI, with the following resulting values: ~0.1 solar for one HVC (complex C), ~0.3 solar for the Magellanic Stream, ~0.5 solar for a southern IVC, and ~ solar for two northern IVCs (the IV Arch and LLIV Arch). Finally, approximate values in the range 0.5-2 solar are found for three more IVCs. 2) Depletion patterns in IVCs are like those in warm disk or halo gas. 3) Most distance limits are based on strong UV lines of CII, SiII and MgII, a few on CaII. Distance limits for major HVCs are >5 kpc, while distance brackets for several IVCs are in the range 0.5-2 kpc. 4) Mass limits for major IVCs are 0.5-8x10^5 M_sun, but for major HVCs they are >10^6 M_sun. 5) The CaII/HI ratio varies by up to a factor 2-5 within a single cloud, somewhat more between clouds. 6) The NaIHI ratio varies by a factor >10 within a cloud, and even more between clouds. Thus, CaII can be useful for determining both lower and upper distance limits, but NaI only yields upper limits.Comment: To appear in the "Astrophysical Journal Supplement"; 82 pages; figures 6, 9 and 10 are in color; degraded figures (astro-ph restriction) - ask for good version

    Differences in genome-wide gene expression response in peripheral blood mononuclear cells between young and old men upon caloric restriction

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    Background: Caloric restriction (CR) is considered to increase lifespan and to prevent various age-related diseases in different nonhuman organisms. Only a limited number of CR studies have been performed on humans, and results put CR as a beneficial tool to decrease risk factors in several age-related diseases. The question remains at what age CR should be implemented to be most effective with respect to healthy aging. The aim of our study was to elucidate the role of age in the transcriptional response to a completely controlled 30 % CR diet on immune cells, as immune response is affected during aging. Ten healthy young men, aged 20–28, and nine healthy old men, aged 64–85, were subjected to a 2-week weight maintenance diet, followed by 3 weeks of 30 % CR. Before and after 30 % CR, the whole genome gene expression in peripheral blood mononuclear cells (PBMCs) was assessed. Results: Expression of 554 genes showed a different response between young and old men upon CR. Gene set enrichment analysis revealed a downregulation of gene sets involved in the immune response in young but not in old men. At baseline, immune response-related genes were higher expressed in old compared to young men. Upstream regulator analyses revealed that most potential regulators were controlling the immune response. Conclusions: Based on the gene expression data, we theorise that a short period of CR is not effective in old men regarding immune-related pathways while it is effective in young men

    Geriatric palliative care: a view of its concept, challenges and strategies.

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    In aging societies, the last phase of people's lives changes profoundly, challenging traditional care provision in geriatric medicine and palliative care. Both specialties have to collaborate closely and geriatric palliative care (GPC) should be conceptualized as an interdisciplinary field of care and research based on the synergies of the two and an ethics of care.Major challenges characterizing the emerging field of GPC concern (1) the development of methodologically creative and ethically sound research to promote evidence-based care and teaching; (2) the promotion of responsible care and treatment decision making in the face of multiple complicating factors related to decisional capacity, communication and behavioural problems, extended disease trajectories and complex social contexts; (3) the implementation of coordinated, continuous care despite the increasing fragmentation, sectorization and specialization in health care.Exemplary strategies to address these challenges are presented: (1) GPC research could be enhanced by specific funding programs, specific patient registries and anticipatory consent procedures; (2) treatment decision making can be significantly improved using advance care planning programs that include adequate decision aids, including those that address proxies of patient who have lost decisional capacity; (3) care coordination and continuity require multiple approaches, such as care transition programs, electronic solutions, and professionals who act as key integrators

    Integration of oncology and palliative care : a Lancet Oncology Commission

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    Full integration of oncology and palliative care relies on the specific knowledge and skills of two modes of care: the tumour-directed approach, the main focus of which is on treating the disease; and the host-directed approach, which focuses on the patient with the disease. This Commission addresses how to combine these two paradigms to achieve the best outcome of patient care. Randomised clinical trials on integration of oncology and palliative care point to health gains: improved survival and symptom control, less anxiety and depression, reduced use of futile chemotherapy at the end of life, improved family satisfaction and quality of life, and improved use of health-care resources. Early delivery of patient-directed care by specialist palliative care teams alongside tumour-directed treatment promotes patient-centred care. Systematic assessment and use of patient-reported outcomes and active patient involvement in the decisions about cancer care result in better symptom control, improved physical and mental health, and better use of health-care resources. The absence of international agreements on the content and standards of the organisation, education, and research of palliative care in oncology are major barriers to successful integration. Other barriers include the common misconception that palliative care is end-of-life care only, stigmatisation of death and dying, and insufficient infrastructure and funding. The absence of established priorities might also hinder integration more widely. This Commission proposes the use of standardised care pathways and multidisciplinary teams to promote integration of oncology and palliative care, and calls for changes at the system level to coordinate the activities of professionals, and for the development and implementation of new and improved education programmes, with the overall goal of improving patient care. Integration raises new research questions, all of which contribute to improved clinical care. When and how should palliative care be delivered? What is the optimal model for integrated care? What is the biological and clinical effect of living with advanced cancer for years after diagnosis? Successful integration must challenge the dualistic perspective of either the tumour or the host, and instead focus on a merged approach that places the patient's perspective at the centre. To succeed, integration must be anchored by management and policy makers at all levels of health care, followed by adequate resource allocation, a willingness to prioritise goals and needs, and sustained enthusiasm to help generate support for better integration. This integrated model must be reflected in international and national cancer plans, and be followed by developments of new care models, education and research programmes, all of which should be adapted to the specific cultural contexts within which they are situated. Patient-centred care should be an integrated part of oncology care independent of patient prognosis and treatment intention. To achieve this goal it must be based on changes in professional cultures and priorities in health care
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