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101.
102.
The paper outlines some of the actions taken by Severn Trent Water to achieve compliance with consent limits since the implementation of the Control of Pollution Act (Part II) in 1985.
Prior to and since 1985, Severn Trent Water has undertaken an extensive programme to analyse the reasons for failure and carry out remedial work. A major feature of this programme, which has been further stimulated by privatization, has been the need to reduce the lead time for carrying out improvements.
The paper discusses the means by which this has been achieved, including the introduction of the 'fast-track'initiative and the 'process matrix'.
Other aspects are outlined including initiatives to develop more robust processes, computerized work scheduling, extensive training programmes and best practice studies.  相似文献   
103.
J. GAY  BSc  MS  CEng  MICE  R. WEBSTER  BA  MSc  D. ROBERTS  BA  MSc  M. TRETT  BSc  FLS 《Water and Environment Journal》1991,5(5):573-580
The environmental implications of implementing the requirement for treatment of coastal sewage prior to discharge, which were put forward in an EC draft Directive on municipal waste-water treatment, are examined. In order to establish the current situation, the results of a national survey of coastal and estuarine sewage discharges are presented. A review of the impact of sewage discharges on the marine environment is presented in conjunction with an assessment of the impact of sewage-treatment processes on the land and in the air. These aspects are integrated into overall conclusions about net environmental impact. Finally, a decision-tree approach to the assignment of priority to additional action required at individual locations is developed.  相似文献   
104.
巴恒静  杨英姿 《建筑技术》2001,32(10):656-658
目前冬期施工中,巳有相关数量的大流动度的负温防冻剂混凝土替代了原有的低塑性防冻剂混凝土。但防冻泵送剂尚无明确的检验标准。为此选取两种防冻剂进行试验,结果表明无论是高效减水剂还是增加用水量改善混凝土的工作性,混凝土硬化初期的性能均受到明显影响。  相似文献   
105.
C. Njiru  BSc  MSc  CEng  MICE  I. K. Smout  BA  MSc  CEng  FICE  MIAgrE  K. Sansom  BSc  MSc  CEng  MICE 《Water and Environment Journal》2001,15(4):277-281
A key challenge for managers of water utilities in developing countries is to provide services to the rising urban population in a financially sustainable manner. The paper examines the management of water services in an African city which piloted service differentiation and pricing. Among the key findings was that substantial improvement in the provision of water services to the urban poor was attained. Cost recovery was achieved through innovative structuring of public/private partnerships, an appropriate pricing policy, and flexible payment systems. The project demonstrates that (a) by structuring service delivery with appropriate pricing, utilities could serve more customers (including people living in informal settlements) at affordable cost and achieve financial sustainability, and (b) service differentiation and appropriate pricing has the potential to improve urban water services in low-income countries.  相似文献   
106.
Depressed geriatric patients show substantial intersubject variability in cognitive performance, which complicates attempts to evaluate the cognitive effects of depression and of antidepressant therapy. This variability may reflect the multiple medications older patients take, many of which have anticholinergic effects. This study examined whether serum anticholinergicity (SA) explained some of the variability in depressed geriatric patients' memory performance. Before starting antidepressant treatment, 36 elderly depressed subjects were given a verbal learning test. At the same time, a blood sample was taken and analyzed by radioreceptor binding assay to determine their SA level. Nineteen of the subjects had detectable levels (mean = 0.28 pmole atropine equivalent). Subjects with an SA of zero showed significantly better delayed recall than did those with a positive SA level. Thus, even very low SA may produce subtle decrements in memory performance, an area of cognition known to be highly sensitive to anticholinergic effects.  相似文献   
107.
Hereditary susceptibility to sarcoidosis is suggested by ethnic preponderance, familial clustering, and multigenerational involvement. The genetics of sarcoidosis cannot be adequately addressed in small samples of patients; a large-scale study with stratification for patient phenotypic differences is necessary. A study that uses both genetic marker and environmental data would be able to control for and examine different causative mechanisms. Until such a well-designed, comprehensive study is carried out, we are left with interesting patterns of disease in families and uncertain allelic associations.  相似文献   
108.
By using proton magnetic resonance spectroscopy ((1)H-MRS), cerebral lactate has been shown to be elevated in a wide variety of pediatric and adult neurological diseases. In this study we compared 36 newborns, infants, and children with elevated lactate peaks on (1)H-MRS with 61 patients without an identifiable lactate signal. (1)H-MRS was acquired from the occipital gray and parietal white matter (8 cm3 volume, STEAM sequence with echo time = 20 msec, repetition time = 3.0 seconds) and data were expressed as ratios of different metabolite peak areas (N-acetylaspartate [NA]/creatine [Cr], NA/choline [Ch], and Ch/Cr) and the presence of a characteristic lactate doublet peak at 1.3 ppm. Outcomes (Pediatric Cerebral Performance Category Scale score; PCPCS) were assigned 6 to 12 months after injury. Patients with lactate peaks were more likely to have suffered a cardiac arrest, were more often hyperglycemic, and had lower Glasgow Coma Scale scores on admission. They were also more likely to have abnormal metabolite ratios when compared with age-matched controls or with patients without detectable lactate. Of prognostic importance, patients with increased lactate were more likely to be severely disabled (39% vs 10%), survive in a persistent vegetative state (13% vs 2%), or have died (39% vs 7%). In contrast, patients with similar conditions without increased lactate were more likely to have had a good outcome (23% vs 3%) or recovered to a mild (38% vs 6%) or moderate disability (20% vs 0%). Our data suggest that (1)H-MRS is useful in the prediction of long-term outcomes in children with neurological disorders. Patients with elevated cerebral lactate are more likely to die acutely or are at greater risk for serious long-term disability.  相似文献   
109.
BACKGROUND: This prospective study assesses the outcome results in 100 consecutive patients with gastroesophageal reflux disease (GERD) treated with a laparoscopic Toupet fundoplication. METHODS: GERD was confirmed by 24-h pH study and/or esophagogastroduodenoscopy (EGD). Pre- and postoperative symptoms, operative times, and perioperative complications were recorded on standardized data forms. Early follow-up was at 3 months and late follow-up, including 24-h pH, manometry, and EGD was at 22 months. RESULTS: Preoperative symptoms included heartburn (92%), regurgitation (58%), water brash (39%), and dysphagia (39%). Mean operative time was 3.2 hours. There were no conversions to celiotomy and there were no mortalities. The perioperative complication rate was 14%; 6% (5/83) of patients reported heartburn at 3 months and 20% (15/74) at 22 months. Early and late dysphagia was 20% (17/83) and 9% (7/74), respectively; 24-h pH testing was abnormal in 90% of symptomatic patients (9/10), 39% of asymptomatic patients (12/31), and 51% overall. CONCLUSIONS: Despite early improvement in reflux symptoms following laparoscopic Toupet fundoplications, there is a high incidence of recurrent GERD. Symptomatic follow-up underestimates the true incidence of 24-h pH-documented reflux. Based on these results we cannot recommend the laparoscopic Toupet repair for GERD patients with normal esophageal motility.  相似文献   
110.
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