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191.
The objective of this study was to assess the effects of two brief training interventions to improve obstetricians' and midwives' explanations to patients of a routine prenatal screening test. Health professionals were randomly allocated to one of two intervention groups or a control group. Information-giving about the test and communication skills were assessed at baseline, post-training and 3-month follow-up from audiotaped consultations. Both intervention groups received a 1-h training session involving small group discussions focused around a video. In addition, one group received individual feedback on their baseline and post-training consultations. Twenty-six midwives and nine obstetricians completed the study according to the protocol. Changes between baseline and post-training, and between baseline and follow-up, were computed. Information-giving and communication skills improved significantly in subjects receiving training and feedback on their performance, with the greatest improvements occurring before feedback was given. Those receiving training without feedback significantly improved their communication skills and showed some improvement in information-giving. These results show that modest improvements in communication can be made with relatively brief training. Greater and more sustained improvements may be found if all staff were trained, and trained on a regular basis.  相似文献   
192.
The responses to pH of abiotic interactions between dissolved humic substances, iron and phosphate were investigated by examining redistributions of 55FeCl3 and 32PO43− added to epilimnetic lakewater from Lake Skjervatjern. The simultaneous movement of 55Fe and 32P to fractions of 10 000–20 000 and > 100 000 Daltons nominal molecular weight, as indicated by Sephadex gel filtration, diminished in response to decreasing pH. Variations in transformations to larger molecular size fractions with incubation time revealed by gel filtration were erratic, but indicated that transformations of added 55Fe and 32P are complete after circa 24 h. Movement of 32P to particle size fractions (>0.2 μm) was not dependent on pH, whilst transformations of 55Fe to material of particle size increased as pH was lowered. Precipitation of added 55Fe and 32P was minimal at all pH values tested. Responses of precipitation losses to pH were not coincident for both radionuclides.  相似文献   
193.
This paper describes a 12-month experiment designed to study the extent of upward migration of (125)I (as a surrogate for (129)I) from near-surface groundwater, through a 50-cm column of soil and into perennial ryegrass. The water table was established at a depth of 45 cm below the soil surface. By 3 months, (125)I had migrated about half way up the soil column. After this, it tended to accumulate just above this mid-point, with only very small amounts being transported to the upper 20 cm of soil. This behaviour seemed to be explained well by soil moisture and redox conditions. The experiment indicated that (125)I was mobile only within the saturated/low redox zone at the base of the soil column and accumulated in the zone of transition between anoxic and oxic soil conditions. Uptake of (125)I by the ryegrass was found to be low.  相似文献   
194.
195.
This paper presents a review of the current status of radioecology and how it might be applied to contribute to a broader range of environmental pollution and contamination problems. In many respects radioecology is a unique and specialised branch of environmental science. However, radioecologists could be much more aware of the similarities and differences between their field and other fields of environmental pollution science. Areas of common interest described herein are exposure and risk assessment, and the problem of the bioavailability of potentially toxic substances in environmental media. It is concluded that radiometric methods and radioecological modelling methods can assist significantly with understanding and quantifying both these issues. The existence of multiple contaminants at many locations around the world dictates that assessment and remediation exercises should be carried out in an integrated fashion, as a partnership between scientific disciplines.  相似文献   
196.
From disaster to sustainable civil society: the Kobe experience   总被引:9,自引:0,他引:9  
Shaw R  Goda K 《Disasters》2004,28(1):16-40
Nine years after the Kobe earthquake in Japan, social issues are still prominent, and the rehabilitation process is still ongoing. The earthquake caused two major changes in Japanese society: an increase in voluntary and non-government activities, and the enhancement of cooperation between local government and the residents' association. People's participation in the decision-making process was a significant achievement. To sustain the efforts generated after the earthquake, the Kobe Action Plan was formulated and tested in different disaster scenarios. The current study suggests that civil societies in urban areas are sustainable if, first, the activities related to daily services are provided by the resident's associations; and second, these are linked to economic incentives. Leadership plays a crucial role in collective decision-making. Creation of the support system is essential for long-term sustainability of civil-society activities. These observations are exemplified in the case study in Nishi Suma, one of the worst-affected areas in the Kobe city.  相似文献   
197.
The use of soluble PO43− as a heavy metal chemical stabilization agent was evaluated for a dust generated from melting or vitrification of municipal solid waste combustion residues. Vitrification dusts contain high concentrations of volatile elements such as Cl, Na, K, S, Pb, and Zn. These elements are present in the dusts largely as simple salts (e.g. PbCl2, ZnSO4) which are highly leachable. At an experimental dose of 0.4 moles of soluble PO43− per kg of residue, the pH-dependent leaching (pH 5,7,9) showed that the treatment was able to reduce equilibrium concentrations by factors of 3 to 100 for many metals; particularly Cd, Cu, Pb and Zn. Bulk and surface spectroscopies showed that the insoluble reaction products are tertiary metal phosphate [e.g. Zn3(PO4)2] and apatite [e.g. Pb5(PO4)3Cl] family minerals. Geochemical thermodynamic equilibrium modeling showed that apatite family and tertiary metal phosphate phases act as controlling solids for the equilibrium concentrations of Ca2+, Zn2+, Pb2+, Cu2+, and Cd2+ in the leachates during pH-dependent leaching. Both end members and ideal solid solutions were seen to be controlling solids. Soluble phosphate effectively converted soluble metal salts into insoluble metal phosphate phases despite the relatively low doses and dry mixing conditions that were used. Soluble phosphate is an effective stabilization agent for divalent heavy metals in melting dusts where leachable metals are present in high concentrations.  相似文献   
198.
The coastal shrimp Crangon crangon is an ecologically and commercially important species but there is limited knowledge of its genetic population structure. We utilised amplified fragment length polymorphisms (AFLPs) to investigate population differentiation among eight sampling locations comprising paired sites from north- and south-western Britain, the eastern English Channel and the Baltic Sea. Initial AMOVA and cluster analysis suggested strong differentiation, but outlier analysis identified three loci that might be subject to selection, one of which showed significant latitudinal variation in allele frequencies. Following exclusion of these outlier loci, and also of a divergent, genetically-impoverished sample from the UK Bristol Channel, cluster analysis revealed three major groupings, corresponding to geographical regions: western Britain, the eastern English Channel and the Baltic Sea. AMOVA identified significant differentiation both within and among these regions, with similar variation explained by each hierarchical level. C. crangon shows greater genetic structuring than has been found in many decapod crustaceans studied to date, and our results are consistent with unstable population sizes and gene flow restricted by distance and probably also hydrographic features. Further investigation of temporal stability in population structure is required, but broad-scale homogeneity of fishery stocks should not be assumed.  相似文献   
199.
Methanol extracts of freshly harvested cells of the marine diatom Phaeodactylum tricornutum were found to produce a feeding deterrent effect in the copepod Tigriopus californicus. Bioassay guided fractionation of the methanol extracts led to the isolation of four compounds possessing feeding deterrent activity. The compounds were identified as apo-10-fucoxanthinal (1), apo-12-fucoxanthinal (2), apo-12-fucoxanthinal (3), and apo-13-fucoxanthinone (4) by detailed spectroscopic analysis and comparison with authentic compounds produced semi-synthetically from fucoxanthin. Compounds 1 to 4 exhibited feeding deterrent responses in T. californicus at concentrations of less than 20 ppm.  相似文献   
200.
王旭辉  Shaw G  朱永官 《环境化学》2003,22(5):511-515
采用水浸取法和硅胶色层法,通过紫外吸收光谱峰定性鉴定了英格兰七种土壤水溶性腐殖酸。沉积土中水溶性腐殖酸均展示了二组峰值,而在草原土中低分子量组份消失。选用γ谱仪测定了沉积土水溶性腐殖酸中的放射性核素^137Cs,采用中子活化测量技术分析了常量钠和氯。结果表明,在高盐含量的沉积土中存在的大量竞争络合离子钠可能是使放射性核素^137Cs与沉积土中水溶性腐殖酸没有直接关系的原因。  相似文献   
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