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121.
The east and south-east of England has the lowest rainfall in the UK, water resources are limited and under pressure through increased demand and population growth. In the late 1990's AW Innovation (the AW R&D group) developed a process that could produce high purity water from sewage effluent using membrane technology. In late 1999 Texas Utilities (TXU) signed a contract with Alpheus Environmental for the supply of high purity water for Peterborough Power Station. The novel treatment plant was built in 1999 - 2000 and opened in July 2000 by the Mayor of Peterborough. This paper is a review of the plant design, the technology used for the treatment process and a summary of the first four years of operation.
Changing from potable water to high purity water produced from sewage effluent has brought significant benefits for the power station resulting in higher purity steam generation while reducing chemical, power and effluent discharge costs. In addition Anglian Water is now saving 1,000 m3 /day of potable water. 相似文献
Changing from potable water to high purity water produced from sewage effluent has brought significant benefits for the power station resulting in higher purity steam generation while reducing chemical, power and effluent discharge costs. In addition Anglian Water is now saving 1,000 m
122.
The goal of orthopaedic interventions is to improve the functional health of patients, particularly physical function. The American Academy of Orthopaedic Surgeons and the Pediatric Orthopaedic Society of North America (POSNA) commissioned a work group to construct functional health outcomes scales for children and adolescents, focusing on musculoskeletal health. The work group developed scales assessing upper extremity function, transfers and mobility, physical function and sports, comfort (pain free), happiness and satisfaction, and expectations for treatment. Parent and adolescent self-report forms were developed and tested on 470 subjects aged 2-18 years. The POSNA scales demonstrated good reliability, construct validity, sensitivity to change over a 9-month period, and ability to outperform a standard instrument, the Child Health Questionnaire physical functioning scale. They were useful for a wide variety of ages and diagnoses. They appear to be ideally suited for orthopaedic surgeons to assess the functional health and efficacy of treatment of their patients at baseline and follow-up. 相似文献
123.
OBJECTIVE: Right-angle dual-headed tomography has increased cardiac SPECT utility by cutting acquisition time in half which enhances gating capabilities. When gating, however, a deceleration in heart rate, due to a return to baseline rate after stress or lessened anxiety at the end of a study, may significantly affect the last step(s) of a gated study with possible frame or information loss. The purpose of this study was to illustrate the artifacts produced in myocardial perfusion studies when a frame or frames are lost in single- and dual-detector SPECT imaging methodologies. METHODS: A near-normal 99mTc-sestamibi study was obtained using a dual-headed camera system fitted with high-resolution, long-bore collimators. The normal study was processed including all frames (1-32). To demonstrate the effect of losing frames on a dual-headed system, the study was processed three different ways to simulate frame loss. RESULTS: Loss of frames at the end of a SPECT acquisition results in significant inferoseptal wall defects, left ventricular lumen narrowing, as well as thinning of the anterior and lateral walls. The overall appearance of the heart is a more oval-shaped heart with decreased perfusion. The effect of losing the last frame in a dual-headed camera system as opposed to losing the last frame in a single-headed camera system is more substantial. CONCLUSION: A scan resulting in the loss of a frame in either a single- or a dual-headed camera system creates artifacts in the myocardial wall and should always be repeated. It is significant to note that artifacts present in a dual-headed system are much more prevalent than in a single-headed system due to the nature of dual-headed acquisition parameters. 相似文献
124.
We have evaluated our practice of tube caecostomies in 21 children operated on from January 1982 to December 1987 at the Royal Hospital for sick children, Bristol, and 18 children operated on at the Paediatric Surgery Unit of the Korle-Bu Teaching Hospital, Accra, Ghana from January 1989 to December 1996. The indications for surgery were, Hirschsprung's disease (36) and idiopathic constipation (3). The definitive procedures involved were Duhamel's procedure in 36, Soave's procedure in 2 and colo-anal anastomosis in 1 case. This method reduces the total number of surgical operations required by the child from 3 to 2, thereby reducing the total period of hospitalisation for the child. A sample technique of tube caecostomy is described in 39 children undergoing corrective surgery. 相似文献
125.
Identification of a novel cysteine string protein variant and expression of cysteine string proteins in non-neuronal cells 总被引:1,自引:0,他引:1
Cysteine string proteins (Csps) are synaptic vesicle proteins thought to be involved in calcium-dependent neurotransmitter release at nerve endings. Here, we report the cloning of two Csp variants, termed Csp1 and Csp2, from bovine adrenal medullary chromaffin cells. The bovine Csp1 appears to be the homologue of rat brain Csp, sharing 95% identity at the amino acid level. The nucleotide sequence of csp2 is identical with that of csp1 except for a 72-base insert which introduces a stop codon into the coding sequence, which would be predicted to result in a truncated protein 3.3 kDa smaller than Csp1. Furthermore, polymerase chain reaction analysis detected homologues of Csp1 and Csp2 in rat kidney, liver, pancreas, spleen, lung, and adrenal gland. Expression of Csps in non-neuronal tissues was confirmed by Northern blotting and by immunoblotting with anti-Csp1 antiserum which also demonstrated expression of both full-length and truncated Csps in spleen. The widespread tissue distribution is inconsistent with a role of Csps as specific regulators of presynaptic calcium channels as previously proposed. We suggest that Csps may have a more general role in membrane traffic in non-neuronal as well as neuronal cells. 相似文献
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Haploid Saccharomyces cerevisiae cells find each other during conjugation by orienting their growth toward each other along pheromone gradients (chemotropism). However, when their receptors are saturated for pheromone binding, yeast cells must select a mate by executing a default pathway in which they choose a mating partner at random. We previously demonstrated that this default pathway requires the SPA2 gene. In this report we show that the default mating pathway also requires the AXL1, FUS1, FUS2, FUS3, PEA2, RVS161, and BNI1 genes. These genes, including SPA2, are also important for efficient cell fusion during chemotropic mating. Cells containing null mutations in these genes display defects in cell fusion that subtly affect mating efficiency. In addition, we found that the defect in default mating caused by mutations in SPA2 is partially suppressed by multiple copies of two genes, FUS2 and MFA2. These findings uncover a molecular relationship between default mating and cell fusion. Moreover, because axl1 mutants secrete reduced levels of a-factor and are defective at both cell fusion and default mating, these results reveal an important role for a-factor in cell fusion and default mating. We suggest that default mating places a more stringent requirement on some aspects of cell fusion than does chemotropic mating. 相似文献
129.
KL Childs FR Miller MM Cordonnier-Pratt LH Pratt PW Morgan JE Mullet 《Canadian Metallurgical Quarterly》1997,113(2):611-619
The Ma3 gene is one of six genes that regulate the photoperiodic sensitivity of flowering in sorghum (Sorghum bicolor [L.] Moench). The ma3R mutation of this gene causes a phenotype that is similar to plants that are known to lack phytochrome B, and ma3 sorghum lacks a 123-KD phytochrome that predominates in light-grown plants and that is present in non-ma3 plants. A population segregating for Ma3 and ma3 was created and used to identify two randomly amplified polymorphic DNA markers linked to Ma3. These two markers were cloned and mapped in a recombinant inbred population as restriction fragment length polymorphisms. cDNA clones of PHYA and PHYC were cloned and sequenced from a cDNA library prepared from green sorghum leaves. Using a genome-walking technique, a 7941-bp partial sequence of PHYB, was determined from genomic DNA from ma3 sorghum. PHYA, PHYB, and PHYC all mapped to the same linkage group. The Ma3-linked markers mapped with PHYB more than 121 centimorgans from PHYA and PHYC. A frameshift mutation resulting in a premature stop codon was found in the PHYB sequence from ma3 sorghum. Therefore, we conclude that the Ma3 locus in sorghum is a PHYB gene that encodes a 123-kD phytochrome. 相似文献
130.