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31.
Abstract. Woodland colonization on wetlands is considered to have a detrimental effect on their ecological value, even though detailed analysis of this process is lacking. This paper provides an evaluation of the ecological changes resulting from succession of poor fen (base‐poor mire) to willow wet woodland on Goss Moor NNR in Cornwall, UK. Different ages of willow carr were associated with eight understorey communities. During willow colonization, in the ground flora, there was a progressive decrease in poor fen species and an associated increase in woodland species, which appeared to be related to an increase in canopy cover and therefore shade. The most diverse community was found to be the most recent willow and was dominated by poor fen species. The oldest willow was the second most diverse and was associated with a reduction in poor fen species and an increase in woodland species. Architectural features were used successfully to assess the general condition and structure of willow. Tree height and DBH were identified as useful parameters to accurately assess willow age in the field. The implications of active intervention to remove willow in order to conserve the full range of communities within the hydrosere are discussed. 相似文献
32.
Abstract A thermophilic Lactobacillus , isolate VB183, was tested for comparative glucose and pentose utilization. The possible adverse effect of high concentrations of metabolic end products on cell yield was lessened or eliminated by using low substrate concentrations. Possible growth due to intracellular reserve material, was counteracted by starving the cells for 90 min before being used as inoculant. Isolate VB183 exhibited a higher growth rate on glucose (μ= 1.08 h−1 ) than on ribose (μ= 0.76 h−1 ). L. salivarius was included as a pentose non-fermenting control and showed no significant difference between growth on basal medium with and without ribose. VB183 was also found to utilize l (+)-arabinose but not d (−)-arabinose, stressing the importance of the isomer of the sugars tested. 相似文献
33.
Marian Smeulers Lotte Verweij Jolanda M. Maaskant Monica de Boer C. T. Paul Krediet Els J. M. Nieveen van Dijkum Hester Vermeulen 《PloS one》2015,10(4)
Background
One-third of all medication errors causing harm to hospitalized patients occur in the medication preparation and administration phase, which is predominantly a nursing activity. To monitor, evaluate and improve the quality and safety of this process, evidence-based quality indicators can be used.Objectives
The aim of study was to identify evidence-based quality indicators (structure, process and outcome) for safe in-hospital medication preparation and administration.Methods
MEDLINE, EMBASE and CINAHL were searched for relevant studies published up to January 2015. Additionally, nine databases were searched to identify relevant grey literature. Two reviewers independently selected studies if (1) the method for quality indicator development combined a literature search with expert panel opinion, (2) the study contained quality indicators on medication safety, and (3) any of the quality indicators were applicable to hospital medication preparation and administration. A multidisciplinary team appraised the studies independently using the AIRE instrument, which contains four domains and 20 items. Quality indicators applicable to in-hospital medication preparation and administration were extracted using a structured form.Results
The search identified 1683 studies, of which 64 were reviewed in detail and five met the inclusion criteria. Overall, according to the AIRE domains, all studies were clear on purpose; most of them applied stakeholder involvement and used evidence reasonably; usage of the indicator in practice was scarcely described. A total of 21 quality indicators were identified: 5 structure indicators (e.g. safety management and high alert medication), 11 process indicators (e.g. verification and protocols) and 5 outcome indicators (e.g. harm and death). These quality indicators partially cover the 7 rights.Conclusion
Despite the relatively small number of included studies, the identified quality indicators can serve as an excellent starting point for further development of nursing specific quality indicators for medication safety. Especially on the right patient, right route, right time and right documentation there is room future development of quality indicators. 相似文献34.
J J Coleman K C Tan J M Searles T R Hester F Nahai 《Plastic and reconstructive surgery》1989,84(4):589-95; discussion 596-8
Review of 101 patients who underwent 111 free jejunal autografts has demonstrated an absolute procedural failure rate of 13.5 percent. Salvage reconstruction with a second jejunum was successful in six of nine patients and one third-time jejunum was successful, giving an overall salvage rate of 70 percent. There were 33 patients experiencing pharyngocutaneous fistulas, 20 of whom had been previously irradiated. Of these patients, 15 experienced spontaneous closure and 9 others had successful surgical correction. The mortality rate was 5 percent. Eighty-three percent of patients were restored to adequate per oral alimentation. The jejunum, despite its relatively high complication rate, is an excellent method for pharyngoesophageal reconstruction, expeditiously providing return to function for patients with late-stage disease. 相似文献
35.
The sudden and massive Spartina alterniflora dieback at the turn of the millennium generated numerous unanswered questions regarding its mechanistic causes and consequences. This study, conducted during 2007–2008, aimed to elucidate mechanisms of recovery and determine whether recovery was accelerated by replanting efforts. The onset of a severe drought during the summer of 2007, however, provided a potential glimpse into the mechanisms driving dieback events. Study sites were established in two of the hardest hit states, Georgia and Louisiana. Each site had a replicated block design consisting of the following four treatments: reference, dieback, dieback with low density replanting (90 cm spacing), and dieback with high density replanting (30 cm spacing). To assess biogeochemical cycling and ecosystem functioning, we quantified rates of nitrogen fixation, potential nitrification, potential denitrification, and benthic production biannually. All measured process rates decreased following the drought year of 2007. Nitrogen fixation was positively correlated with benthic production rates in Louisiana, while denitrification was positively correlated with benthic production rates in Georgia and Louisiana. The lack of decreased benthic production during the 2007 drought could indicate that benthic microphytes cope with better with drought than plants, but may be outcompeted during non-drought years. Replanting efforts significantly increased ecosystem recovery in Louisiana and to a lesser extent in Georgia. 相似文献
36.
Membrane biogenesis during B cell differentiation: most endoplasmic reticulum proteins are expressed coordinately 总被引:12,自引:2,他引:12 下载免费PDF全文
D L Wiest J K Burkhardt S Hester M Hortsch D I Meyer Y Argon 《The Journal of cell biology》1990,110(5):1501-1511
The induction of high-rate protein secretion entails increased biogenesis of secretory apparatus organelles. We examined the biogenesis of the secretory apparatus in the B cell line CH12 because it can be induced in vitro to secrete immunoglobulin (Ig). Upon stimulation with lipopolysaccharide (LPS), CH12 cells increased secretion of IgM 12-fold. This induced secretion was accompanied by preferential expansion of the ER and the Golgi complex. Three parameters of the rough ER changed: its area and volume increased 3.3- and 3.7-fold, respectively, and the density of membrane-bound ribosomes increased 3.5-fold. Similarly, the area of the Golgi stack increased 3.3-fold, and its volume increased 4.1-fold. These changes provide sufficient biosynthetic capacity to account for the increased secretory activity of CH12. Despite the large increase in IgM synthesis, and because of the expansion of the ER, the concentration of IgM within the ER changed less than twofold during the differentiation process. During the amplification of the rough ER, the expression of resident proteins changed according to one of two patterns. The majority (75%) of rough microsomal (RM) proteins increased in proportion to the increase in rough ER size. Included in this group were both lumenal proteins such as Ig binding protein (BiP), and membrane proteins such as ribophorins I and II. In addition, the expression of a minority (approximately 9%) of RM polypeptides increased preferentially, such that their abundance within the RM of secreting CH12 cells was increased. Thus, the expansion of ER during CH12 differentiation involves preferential increases in the abundance of a few resident proteins, superimposed upon proportional increases in most ER proteins. 相似文献
37.
Fumonisin production by <Emphasis Type="Italic">Fusarium</Emphasis> species isolated from freshly harvested corn in Iran 总被引:1,自引:0,他引:1
Ghiasian SA Rezayat SM Kord-Bacheh P Maghsood AH Yazdanpanah H Shephard GS van der Westhuizen L Vismer HF Marasas WF 《Mycopathologia》2005,159(1):31-40
Fifty-one strains of Fusarium verticillioides and F. proliferatum isolated from corn collected from four different geographic areas in Iran, namely Fars, Khuzestan, Kermanshah and Mazandaran (an endemic oesophageal cancer (OC) area) were evaluated for their ability to produce fumonisins B1 (FB1), B2 (FB2) and B3 (FB3) in corn culture. Fumonisin levels were determined by high-performance liquid chromatography. All tested strains of F. verticillioides and F. proliferatumproduced fumonisins within a wide range of concentrations, 197–9661 g/g, 18–1974 g/g, and 21–1725 g/g for FB1, FB2, and FB3, respectively. The highest mean concentrations of FB1, FB2, and FB3 were 3897, 806 and 827 g/g, respectively. Overall, 61% of the F. verticillioides and F. proliferatum strains produced higher levels of FB3 than FB2. The mean ratios of FB1:FB2, FB1:FB3 and FB1:total fumonisins were 8, 7 and 0.7 for F. verticillioides and 5.7, 10.7 and 0.7 for F. proliferatum, respectively. Significant differences in some of the meteorological data (rainfall, relative humidity and minimum temperature) from the four provinces were observed. Fumonisin levels produced by F. verticillioides strains isolated from Khuzestan province (tropical zone) were significantly (P < 0.01) higher than the other three provinces. This is the first report of the fumonisin-producing ability of F.verticillioides and F. proliferatum strains isolated from corn harvested from different geographic areas in Iran. 相似文献
38.
Hester Soomers Derek Karssenberg Merel B. Soons Pita A. Verweij Jos T. A. Verhoeven Martin J. Wassen 《Ecosystems》2013,16(3):434-451
Biodiversity in wetlands is threatened by habitat loss and fragmentation, of which agricultural activities often are a cause. Dispersal of plant seeds via wind and ditches (water) may contribute to connecting remnant wetland plant populations in modern agricultural landscapes, and help to maintain and restore biodiversity. We developed a spatially explicit model to assess the relative importance of dispersal by wind and dispersal by water through drainage ditches for two wetland plant species in agricultural landscapes: a typical wind disperser and a typical water-disperser. Simulation results show that the typical wind disperser had a much higher capability to disperse by wind (90th percentile <30 m) than the typical water-disperser (90th percentile <2 m). Surprisingly, the capability to disperse via water was similar for the two species: 90th percentile dispersal distances following a combination of wind and water dispersal were between approximately 100 and 1000 m. Dispersal by water transported more seeds over long distances for both species. The main determinants for dispersal distance by water were roughness of the ditch (determined by, for example, bank vegetation) and the presence of obstructions (for example, culverts). Density or direction of the ditch network did not seem to affect water dispersal distances substantially. From a biodiversity conservation perspective, it would be most useful if areas with suitable riparian wetland habitat were intersected with a network of shallow ditches with a high roughness promoting seed deposition. These areas should then be connected to other suitable areas by a few regularly cleaned ditches with no obstructions and low seed trapping probability. 相似文献
39.
Daniela Rojatz Julia Fischer Hester Van de Bovenkamp 《Journal of bioethical inquiry》2018,15(3):351-358
Governments are increasingly inviting patient organizations (POs) to participate in healthcare policymaking. By inviting POs that claim to represent patients, representation comes into being. However, little is known about the circumstances under which governments accept POs as patient representatives. Based on the analysis of relevant legislation, this article investigates the criteria that self-help organizations (SHOs), a special type of PO, must fulfil in order to be accepted as patient representatives by governments in Austria and Germany. Thereby, it aims to contribute to the discussion on the role of governments in steering SHOs. There are different degrees of regulation (very little in Austria, more in Germany). Governments in both countries not only formulate explicit criteria for SHOs with respect to patient representation but also guide SHOs representing patients through implicit criteria for associations. We discuss the findings against concepts of responsiveness, authorization, and accountability. Our findings indicate that governmental steering is not negative per se as indicated by previous research but—depending on legislative criteria—can promote transparency and democratic quality in patient representation. 相似文献
40.
Rapid genetic identification and mapping of enzymatically amplified ribosomal DNA from several Cryptococcus species. 总被引:21,自引:1,他引:21 下载免费PDF全文
Detailed restriction analyses of many samples often require substantial amounts of time and effort for DNA extraction, restriction digests, Southern blotting, and hybridization. We describe a novel approach that uses the polymerase chain reaction (PCR) for rapid simplified restriction typing and mapping of DNA from many different isolates. DNA fragments up to 2 kilobase pairs in length were efficiently amplified from crude DNA samples of several pathogenic Cryptococcus species, including C. neoformans, C. albidus, C. laurentii, and C. uniguttulatus. Digestion and electrophoresis of the PCR products by using frequent-cutting restriction enzymes produced complex restriction phenotypes (fingerprints) that were often unique for each strain or species. We used the PCR to amplify and analyze restriction pattern variation within three major portions of the ribosomal DNA (rDNA) repeats from these fungi. Detailed mapping of many restriction sites within the rDNA locus was determined by fingerprint analysis of progressively larger PCR fragments sharing a common primer site at one end. As judged by PCR fingerprints, the rDNA of 19 C. neoformans isolates showed no variation for four restriction enzymes that we surveyed. Other Cryptococcus spp. showed varying levels of restriction pattern variation within their rDNAs and were shown to be genetically distinct from C. neoformans. The PCR primers used in this study have also been successfully applied for amplification of rDNAs from other pathogenic and nonpathogenic fungi, including Candida spp., and ought to have wide applicability for clinical detection and other studies. 相似文献