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在未来持续多变和不可预测的竞争环境中,保持企业的竞争地位和生存发展的重要概念就是由敏捷制造和动态联盟构成的敏捷竞争的概念。动态联盟的思想加上当今高速信息网的建立和CALS提供的支持全球合作的技术和标准,为我们确定先进制造技术的研究计划,帮助中国的广大企业顺利地进入21世纪的国际合作大环境都有着重要的意义。

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混汞法是一种设备简单、操作简便且应用历史悠久的提金方法,在世界范围内得到了普遍使用,同时也导致了严重的汞污染。本文介绍了混汞法的流程以及汞的释放过程和释放因子;综述了应用混汞法提金的不同国家和地区,对由此引发的大气、水体、生物(包括人体)和土壤汞污染的研究现状,并讨论了采金地区的环境管理政策。

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An oxygen permeable membrane based on Ba0.5Sr0.5Co0.8-Fe0.2O3-delta is used to supply lattice oxide continuously for oxidative dehydrogenation of ethane to ethylene with selectivity as high as 90% at 650degreesC.

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BackgroundAnterior open bite occurs when there is a lack of vertical overlap of the upper and lower incisors. the aetiology is multifactorial including: oral habits, unfavourable growth patterns, enlarged lymphatic tissue with mouth breathing. Several treatments have been proposed to correct this malocclusion, but interventions are not supported by strong scientific evidence.ObjectivesThe aim of this systematic review was to evaluate orthodontic and orthopaedic treatments to correct anterior open bite in children.Search methodsThe following databases were searched: the Cochrane Oral Health Group's Trials Register (to 14 February 2014); the Cochrane Central Register of Controlled Trials (CENTRAL)(The Cochrane Library 2014, Issue 1); MEDLINE via OVID (1946 to 14 February 2014); EMBASE via OVID (1980 to 14 February 2014); LILACS via BIREME Virtual Health Library (1982 to 14 February 2014); BBO via BIREME Virtual Health Library (1980 to 14 February 2014); and SciELO (1997 to 14 February 2014). We searched for ongoing trials via ClinicalTrials.gov (to 14 February 2014). Chinese journals were handsearched and the bibliographies of papers were retrieved.Selection criteriaAll randomised or quasi-randomised controlled trials of orthodontic or orthopaedic treatments or both to correct anterior open bite in children.Data collection and analysisTwo review authors independently assessed the eligibility of all reports identified.Risk ratios (RRs) and corresponding 95% confidence intervals (CIs) were calculated for dichotomous data. the continuous data were expressed as described by the author.Main resultsThree randomised controlled trials were included comparing: effects of Frankel's function regulator-4 (FR-4) with lip-seal training versus no treatment; repelling-magnet splints versus bite-blocks; and palatal crib associated with high-pull chincup versus no treatment.The study comparing repelling-magnet splints versus bite-blocks could not be analysed because the authors interrupted the treatment earlier than planned due to side effects in four of ten patients.FR-4 associated with lip-seal training (RR = 0.02 (95% CI 0.00 to 0.38)) and removable palatal crib associated with high-pull chincup (RR = 0.23 (95% CI 0.11 to 0.48)) were able to correct anterior open bite.No study described: randomisation process, sample size calculation, there was not blinding in the cephalometric analysis and the two studies evaluated two interventions at the same time. These results should be therefore viewed with caution.Authors' conclusionsThere is weak evidence that the interventions FR-4 with lip-seal training and palatal crib associated with high-pull chincup are able to correct anterior open bite. Given that the trials included have potential bias, these results must be viewed with caution. Recommendations for clinical practice cannot be made based only on the results of these trials. More randomised controlled trials are needed to elucidate the interventions for treating anterior open bite.

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BackgroundMechanical ventilation is important in caring for patients with critical illness. Clinical complications, increased mortality, and high costs of health care are associated with prolonged ventilatory support or premature discontinuation of mechanical ventilation. Weaning refers to the process of gradually or abruptly withdrawing mechanical ventilation. the weaning process begins after partial or complete resolution of the underlying pathophysiology precipitating respiratory failure and ends with weaning success (successful extubation in intubated patients or permanent withdrawal of ventilatory support in tracheostomized patients).ObjectivesTo evaluate the effectiveness and safety of two strategies, a T-tube and pressure support ventilation, for weaning adult patients with respiratory failure that required invasive mechanical ventilation for at least 24 hours, measuring weaning success and other clinically important outcomes.Search methodsWe searched the following electronic databases: Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2012, Issue 6); MEDLINE (via PubMed) (1966 to June 2012); EMBASE (January 1980 to June 2012); LILACS (1986 to June 2012); CINAHL (1982 to June 2012); SciELO (from 1997 to August 2012); thesis repository of CAPES (Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior) (http://capesdw.capes.gov.br/capesdw/) (August 2012); and Current Controlled Trials (August 2012).We reran the search in December 2013. We will deal with any studies of interest when we update the review.Selection criteriaWe included randomized controlled trials (RCTs) that compared a T-tube with pressure support (PS) for the conduct of spontaneous breathing trials and as methods of gradual weaning of adult patients with respiratory failure of various aetiologies who received invasive mechanical ventilation for at least 24 hours.Data collection and analysisTwo authors extracted data and assessed the methodological quality of the included studies. Meta-analyses using the random-effects model were conducted for nine outcomes. Relative risk (RR) and mean difference (MD) or standardized mean difference (SMD) were used to estimate the treatment effect, with 95% confidence intervals (CI).Main resultsWe included nine RCTs with 1208 patients; 622 patients were randomized to a PS spontaneous breathing trial (SBT) and 586 to a T-tube SBT. the studies were classified into three categories of weaning: simple, difficult, and prolonged. Four studies placed patients in two categories of weaning. Pressure support ventilation (PSV) and a T-tube were used directly as SBTs in four studies (844 patients, 69.9% of the sample). in 186 patients (15.4%) both interventions were used along with gradual weaning from mechanical ventilation; the PS was gradually decreased, twice a day, until it was minimal and periods with a T-tube were gradually increased to two and eight hours for patients with difficult and prolonged weaning. in two studies (14.7% of patients) the PS was lowered to 2 to 4 cm H2O and 3 to 5 cm H2O based on ventilatory parameters until the minimal PS levels were reached. PS was then compared to the trial with the T-tube (TT).We identified 33 different reported outcomes in the included studies; we took 14 of them into consideration and performed meta-analyses on nine. With regard to the sequence of allocation generation, allocation concealment, selective reporting and attrition bias, no study presented a high risk of bias. We found no clear evidence of a difference between PS and TT for weaning success (RR 1.07, 95% CI 0.97 to 1.17, 9 studies, low quality of evidence), intensive care unit (ICU) mortality (RR 0.81, 95% CI 0.53 to 1.23, 5 studies, low quality of evidence), reintubation (RR 0.92, 95% CI 0.66 to 1.26, 7 studies, low quality evidence), ICU and long-term weaning unit (LWU) length of stay (MD -7.08 days, 95% CI -16.26 to 2.1, 2 studies, low quality of evidence) and pneumonia (RR 0.67, 95% CI 0.08 to 5.85, 2 studies, low quality of evidence). PS was significantly superior to the TT for successful SBTs (RR 1.09, 95% CI 1.02 to 1.17, 4 studies, moderate quality of evidence). Four studies reported on weaning duration, however we were unable to combined the study data because of differences in how the studies presented their data. One study was at high risk of other bias and four studies were at high risk for detection bias. Three studies reported that the weaning duration was shorter with PS, and in one study the duration was shorter in patients with a TT.Authors' conclusionsTo date, we have found evidence of generally low quality from studies comparing pressure support ventilation (PSV) and with a T-tube. the effects on weaning success, ICU mortality, reintubation, ICU and LWU length of stay, and pneumonia were imprecise. However, PSV was more effective than a T-tube for successful spontaneous breathing trials (SBTs) among patients with simple weaning. Based on the findings of single trials, three studies presented a shorter weaning duration in the group undergoing PS SBT, however a fourth study found a shorter weaning duration with a T-tube.

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BackgroundAsthma is a common condition characterised by airway inflammation and airway narrowing, which can result in intermittent symptoms of wheezing, coughing and chest tightness, possibly limiting activities of daily life. Water-based exercise is believed to offer benefits for people with asthma through pollen-free air, humidity and effects of exercise on physical function.ObjectivesTo evaluate the effectiveness and safety of water-based exercise for adults with asthma.Search methodsWe searched the Cochrane Airways Group Specialised Register of Trials (CAGR), the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), the Allied and Complementary Medicine Database (AMED), PsycINFO, the Latin American and Caribbean Health Science Information Database (LILACS), the Physiotherapy Evidence Database (PEDro), the System for Information on Grey Literature in Europe (SIGLE) and Google Scholar on 13 May 2014. We handsearched ongoing clinical trial registers and meeting abstracts of the American Thoracic Society (ATS), the European Respiratory Society (ERS) and the British Thoracic Society (BTS).Selection criteriaWe included all randomised controlled trials (RCTs) of adults with asthma comparing a water-based exercise group versus one or more of the following groups: usual care, land-based exercise, non-exercise.Data collection and analysisTwo review authors (AJG, VS) independently extracted data fromthe primary studies using a standard form developed for this purpose, which includes methods, participants, interventions and outcomes. We contacted trial authors to request additional data. Data were input by one review author and were double-checked by a second review author.Main resultsIn this systematic review, we provide a narrative synthesis of available evidence from three small studies including 136 adult participants. the studies were at high risk of bias. No meta-analysis was possible because of methodological and interventional heterogeneity between included studies. the primary outcomes of quality of life and exacerbations leading to use of steroids were not reported by these studies. for exacerbations leading to health centre/hospital visits, uncertainty was wide because a very small number of events was reported (in a single study). Secondary outcomes symptoms, lung function, changes in medication and adverse effects, where available, described for each included study. the overall quality of the studies was very low, and no clear differences were noted between water-based exercise and comparator treatments. Therefore, we remain very uncertain about the effects of water-based exercise for adults with asthma.Authors' conclusionsThe small number of participants in the three included studies, the clinical and methodological heterogeneity observed and the high risk of bias assessed mean that we are unable to assess the place of water-based exercise in asthma. Randomised controlled trials are needed to assess the efficacy and safety of water-based exercise for adults with asthma. for future research, we suggest greater methodological rigour (participant selection, blinding of outcome assessors, reporting of all outcomes analysed and registering of the study protocol).

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Much has been published in recent years about the desirable nature of facilitated interactions in on-line discussions with educational purposes. However little has been reported about the roles which tutors actually adopt in real life learning contexts, how these range between ‘tutoring, ‘managing’ and ‘facilitating’, and what the distinctions between these three roles may be. In this paper choices of priorities in e-moderation, which were made in three naturalistic (real life) case studies by three higher education practitioners, are identified and discussed. These contrasting approaches were captured and analysed using grounded theory principles. The paper also discusses these occasions when the facilitation was less effective than might have been desired. It finally summarises the potential of various approaches within e-moderation – and some of the attendant risks. The finding is that principles and practices developed for face-to-face support of student-directed learning were found equally applicable in e-moderated online group work, despite several significant differences between the two types of setting. Keywords: higher education, e-learning, e-moderation, asynchronous discussions, learning outcomes, grounded theory

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The setting, marking and providing feedback on assessments forms an important part of a tutor’s role. Studies into the use of feedback and how it is interpreted by students indicate a mismatch between what students are looking for and what tutors think they are giving. Tutors comment that students are more interested in the mark than the feedback, and yet students indicate that they do not get enough feedback, or that it is not useful. This study investigates student and staff perceptions of the linking of marking and feedback in face-to-face sessions. A cohort of year one university students were given the option of receiving either written feedback or a 15 minute meeting with one of their tutors to have their essay marked with them. Forty nine students chose face-to-face marking, the remaining 35 students received written feedback. Focus groups were used to investigate the student experience. Staff members were also asked to reflect on the process. Students and staff found the experience of face-to-face marking beneficial and positive. Both felt that the time spent together allowed for a feedback dialogue about the piece of work, and that staff could explain and justify why marks were given.

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Hardy, N. W., Barnes, D. P., Lee, L. H. (1989). Automatic diagnosis of task faults in flexible manufacturing systems. Robotica, 7 (1):25-35

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V. Robinson, N. W. Hardy, D. P. Barnes, C. J. Price, M. H. Lee. Experiences with a knowledge engineering toolkit: an assessment in industrial robotics. Knowledge Engineering Review, 2 (1):43-54, 1987.

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C.J.Price, D.R.Pugh, N.A.Snooke, J.E.Hunt, M.S.Wilson, Combining Functional and Structural Reasoning for Safety Analysis of Electrical Designs, Knowledge Engineering Review, vol 12:3, pp.271-287, 1997.

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B.M. Brown, M. Marletta, S. Naboko, I. Wood: Boundary triplets and M-functions for non-selfadjoint operators, with applications to elliptic PDEs and block operator matrices, J. London Math. Soc., June 2008; 77: 700-718. The full text of this article will be made available in this repository in June 2009 Sponsorship: EPSRC,INTAS

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David Lavallee, Hannah K. Robinson, In pursuit of an identity: A qualitative exploration of retirement from women's artistic gymnastics, Psychology of Sport and ExerciseVolume 8, Issue 1, , January 2007, Pages 119-141. RAE2008

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Wylleman, P., Alfermann, D., Lavallee, D. (2004). Career transitions in sport: European perspectives. Psychology of Sport and Exercise, 5 (1), 7-20 RAE2008

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North, J., Lavallee, D., An investigation of potential users of career transition services in the United Kingdom, Psychology of Sport and Exercise, Vol. 5, No. 1. (January 2004), pp. 77-84. RAE2008