138 research outputs found
Heuristics and soft systems of health care risk management
The formal management of risk was an idea in its early stages of introduction into the National Health Service when this research started. In this thesis I document the development of my thinking as an acute hospital risk manager over the last five years as I developed the Trust's risk management system. Using Action Learning as the research approach, I explored theories and concepts and tested them in the fire of real world action and reflective questioning of experiences. The definition of risk is explored in relation to health care, as are theapproaches used to manage these risks. A key finding is that risk management decision making does not generally fit into either programmed or non-programmed decision making models but neither do decision makers guess. Decision makers tend to use heuristics, which are simple rules of thumb, which generally help them make the right decision with minimum mental effort. However, heuristics also tend to be applied inappropriately and can result in an organisation being exposed to unacceptable levels ofserious risk. A number of key heuristics are identified and they appear to fall into two general types, B-heuristics and E-heuristics. The B-heuristics are 'basic' in form and can be summarised as a simple sentence while, E-heuristics have an 'extended' form which can be summarised as a list of related simple sentences.Knowledge of heuristics helped in the design of the Trust's risk management which has been implemented and its effectiveness tested in the field. This field testing has demonstrated that the worst effects of heuristics can bemitigated by effective soft-system design
The relevance of particulate organic carbon (POC) for carbon composition in the pore water of drained and rewetted fens of the "Donauried" (South-Germany)
International audienceNumerous studies have dealt with carbon (C) concentrations in Histosols, but there are no studies quantifying the relative importance of all individual C components in pore waters. For this study, measurements were made of all the carbon components (i.e., particulate organic carbon, POC; dissolved organic carbon, DOC; dissolved inorganic carbon, DIC; dissolved methane, CH4) in the soil pore water of a calcareous fen under three different water management regimes (re-wetted, deeply and moderately drained). Pore water was collected weekly or biweekly (April 2004 to April 2006) at depths between 10 and 150 cm. The main results obtained were: (1) DIC (94?280 mg C l?1) was the main C-component. (2) POC and DOC concentrations in the pore water (14?125 mg C l?1 vs. 41?95 mg C l?1) were pari passu. (3) Dissolved CH4 was the smallest C component (0.005?0.9 mg C l?1). Interestingly, about 30% of the POM particles were colonized by microbes indicating that they are active in the internal C transfer in the soil profile ("C-Shuttles"). Consequently, it was concluded that POC is at least as important as DOC for internal soil C turnover. There is no reason to assume significant biochemical differences between POC and DOC as they only differ in size. Therefore, both POC and DOC fractions are essential components of C budgets of peatlands. Furthermore dissolved CO2 in all forms of DIC apparently is an important part of peatland C-balances
Support of Unrelated Stem Cell Donor Searches by Donor Center-Initiated HLA Typing of Potentially Matching Donors
Large registries of potential unrelated stem cell donors have been established in order to enable stem cell transplantation for patients without HLA-identical related donors. Donor search is complicated by the fact that the stored HLA information of many registered donors is incomplete. We carried out a project that was aimed to improve chances of patients with ongoing donor searches to find an HLA-matched unrelated donor. For that purpose, we carried out additional donor center-initiated HLA-DRB1 typing of donors who were only typed for the HLA loci A and B so far and were potential matches for patients in need of a stem cell transplant. In total, 8,861 donors were contacted for donor center-initiated HLA-DRB1 typing within 1,089 donor searches. 12 of these donors have donated stem cells so far, 8 thereof for their respective target patients. We conclude that chances of patients with ongoing donor searches to find an HLA-matched unrelated donor can indeed be improved by donor-center initiated typing that is carried out in addition to the standard donor search process. Our results also raise questions regarding the appropriate use of incompletely typed donors within unrelated donor searches
Short- and long-term effects of crop residues and of phosphorus fertilization on pearl millet yield on an acid sandy soil in Niger, West Africa
Field experiments were conducted during the rainy seasons of 1990 and 1991 on an acid sandy soil (Luvic Arenosol) in Niger, to assess long-term (since 1986) andshort-term (since 1990) effectsof millet straw (cropresidues) at different amounts (2 t and 6 t ha−1) and modes of application (incorporation, mulching and burning), andofphosphorus (P) fertilization on dry matter yield of pearl millet [Pennisetum glaucum (L.) R. Br.]. Especially long-term, but also short-term application ofcropresidues increased dry matter yield of pearl millet by more than 60%, whereas their omission decreased yield immediately. Compared to mulching or burning, higher yields were obtained with incorporation ofcropresidues. When cropresidues were applied as mulch, dry matter yield was increased to the same extent by 2 t and 6 t ha−1. Similar dry matter yields were achieved with cropresidues (-P) to those with P fertilizer only. An additional yield increase could be obtained by simultaneous application ofcropresiduesand P. Without cropresidues, potassium (K) concentrations in the shoot dry matter indicated K deficiency. With cropresidues considerable amounts of K (15 kg t−1) were provided and raised the K concentrations in the plants to the sufficiency range. Although with cropresidues some P was provided (1.5 kg t−1), the beneficial effects were primarily attributed to increased P acquisition by the millet plants, which was reflected in enhanced root growth in the topsoil (0–10 cm
Intermediate water links to Deep Western Boundary Current variability in the subtropical NW Atlantic during marine isotope stages 5 and 4
Author Posting. © American Geophysical Union, 2007. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Paleoceanography 22 (2007): PA3209, doi:10.1029/2006PA001409.Records from Ocean Drilling Program Sites 1057 and 1059 (2584 m and 2985 m water depth, respectively) have been used to reconstruct the behavior of the Deep Western Boundary Current (DWBC) on the Blake Outer Ridge (BOR) from 130 to 60 kyr B.P. (marine isotope stage (MIS) 5 and the 5/4 transition). Site 1057 lies within Labrador Sea Water (LSW) but close to the present-day boundary with Lower North Atlantic Deep Water (LNADW), while Site 1059 lies within LNADW. High-resolution sortable silt mean (inline equation) grain size and benthic δ 13C records were obtained, and changes in the DWBC intensity and spatial variability were inferred. Comparisons are made with similar proxy records generated for the Holocene from equivalent depth cores on the BOR. During MIS 5e, inline equation evidence at Site 1057 suggests slower relative flow speeds consistent with a weakening and a possible shoaling of the LSW-sourced shallower limb of the DWBC that occupies these depths today. In contrast, the paleocurrent record from the deeper site suggests that the fast flowing deep core of the DWBC was located close to its modern depth below 3500 m. During this interval the benthic δ 13C suggests little chemical stratification of the water column and the presence of a near-uniform LNADW-dominated water mass. After ∼111 kyr B.P. the inline equation record at Site 1057 increases to reach values similar to Site 1059 for the rest of MIS 5. The strengthening of flow speeds at the shallow site may correspond to the initiation of Glacial North Atlantic Intermediate Water formation also suggested by a divergence in the benthic δ 13C records with Site 1057 values increasing to ∼1.2‰. Coupled suborbital oscillations in DWBC flow variability and paleohydrography persisted throughout MIS 5. Comparison of these data with planktonic δ 18O records from the sites and alkenone-derived sea surface temperature (SST) estimates from the nearby Bermuda Rise suggest a hitherto unrecognized degree of linkage between oscillations in subtropical North Atlantic SST and DWBC flow.This work was funded by the United
Kingdom Natural Environment Research Council and supported by the
NERC Radiocarbon Laboratory
Differentiation of plant derived organic matter in soil, loess and rhizoliths based on n-alkane molecular proxies
Zur Pathologie der Drüse des Bartholin und zum Verständnis des blastomatösen Wachstums
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