713 research outputs found

    Energy efficient engine. Fan and quarter-stage component performance report

    Get PDF
    The fan configuration for the general Electric/NASA Energy Efficient Engine was selected following an extensive preliminary design study. The fan has an inlet radius ratio of 0.342 and a specific flowrate of 208.9 Kg/sec/sq. m (42.8 1bm/sec/sq. ft). The design corrected tip speed is 411.5 m/sec (1350 ft/sec) producing a bypass flow total-pressure ratio of 1.65 and a core flow total-pressure ratio of 1.6. The design bypass ratio is 6.8. The aerodynamic design point corresponds to the maximum climb power setting at Mach 0.8 and 10.67 Km (35,000 ft) altitude. The fully-instrumented fan component was tested in the Lynn Large Fan Test Facility in 1981. The overall performance results, reported herein, showed excellent fan performance with the fan meeting all of its component test goals of flow, efficiency and stall margin

    What is the contribution of physician associates in hospital care in England? A mixed methods, multiple case study.

    Get PDF
    OBJECTIVES: To investigate the deployment of physician associates (PAs); the factors supporting and inhibiting their employment and their contribution and impact on patients' experience and outcomes and the organisation of services. DESIGN: Mixed methods within a case study design, using interviews, observations, work diaries and documentary analysis. SETTING: Six acute care hospitals in three regions of England in 2016-2017. PARTICIPANTS: 43 PAs, 77 other health professionals, 28 managers, 28 patients and relatives. RESULTS: A key influencing factor supporting the employment of PAs in all settings was a shortage of doctors. PAs were found to be acceptable, appropriate and safe members of the medical/surgical teams by the majority of doctors, managers and nurses. They were mainly deployed to undertake inpatient ward work in the medical/surgical team during core weekday hours. They were reported to positively contribute to: continuity within their medical/surgical team, patient experience and flow, inducting new junior doctors, supporting the medical/surgical teams' workload, which released doctors for more complex patients and their training. The lack of regulation and attendant lack of authority to prescribe was seen as a problem in many but not all specialties. The contribution of PAs to productivity and patient outcomes was not quantifiable separately from other members of the team and wider service organisation. Patients and relatives described PAs positively but most did not understand who and what a PA was, often mistaking them for doctors. CONCLUSIONS: This study offers new insights concerning the deployment and contribution of PAs in medical and surgical specialties in English hospitals. PAs provided a flexible addition to the secondary care workforce without drawing from existing professions. Their utility in the hospital setting is unlikely to be completely realised without the appropriate level of regulation and authority to prescribe medicines and order ionising radiation within their scope of practice

    Geriatrics Attitudes and Knowledge Among Surgical and Medical Subspecialty House Officers

    Full text link
    To examine geriatrics knowledge and attitudes of non-primary care house officers (HOs) before and after a multidisciplinary faculty development program. DESIGN : Serial cross-sectional surveys. PARTICIPANTS : HOs. SETTING : A large midwestern academic medical center. INTERVENTION : Faculty from seven surgical and six medical subspecialties participated in weekly seminars for 9 months and implemented geriatrics curricula in their HO programs. MEASUREMENTS : HO geriatrics attitudes and knowledge were measured using the University of California at Los Angeles Geriatrics Attitudes Scale (GAS; 14 items), two scales of the Maxwell Sullivan test (Therapeutic Potential and Time/Energy; six items each; lower scores denote more-favorable attitudes), and the Geriatrics Clinical Knowledge Assessment (20 multiple choice items; range 0–100%). Repeat surveys were administered in seven disciplines after geriatrics curriculum implementation. RESULTS : Baseline (n=175) geriatrics attitudes were favorable (e.g., 3.7 for GAS; 2.1 for Time/Energy), with more-favorable attitudes among medical subspecialty than surgical HOs (e.g., mean GAS 3.8 and 3.6, respectively; P =.001), and with advanced training. Mean baseline knowledge scores were 65.1% among all HOs. No differences in attitudes or knowledge were observed between the first (n=100) and second (n=90) cohorts in the seven disciplines that administered subsequent tests. CONCLUSION : Geriatrics attitudes of non-primary care HOs are positive, and knowledge is moderate, suggesting need for and potential effect of geriatrics curricula. Demonstrating effects on learner outcomes of faculty development programs may require more than one faculty member per discipline and measures that are curriculum-specific and detailed rather than general and brief.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66180/1/j.1532-5415.2007.01475.x.pd

    On the generalized Davenport constant and the Noether number

    Full text link
    Known results on the generalized Davenport constant related to zero-sum sequences over a finite abelian group are extended to the generalized Noether number related to the rings of polynomial invariants of an arbitrary finite group. An improved general upper bound is given on the degrees of polynomial invariants of a non-cyclic finite group which cut out the zero vector.Comment: 14 page

    Comparing physician associates and foundation year two doctors-in-training undertaking emergency medicine consultations in England: a mixed-methods study of processes and outcomes.

    Get PDF
    OBJECTIVES: To compare the contribution of physician associates to the processes and outcomes of emergency medicine consultations with that of foundation year two doctors-in-training. DESIGN: Mixed-methods study: retrospective chart review using 4 months' anonymised clinical record data of all patients seen by physician associates or foundation year two doctors-in-training in 2016; review of a subsample of 40 records for clinical adequacy; semi-structured interviews with staff and patients; observations of physician associates. SETTING: Three emergency departments in England. PARTICIPANTS: The records of 8816 patients attended by 6 physician associates and 40 foundation year two doctors-in-training; of these n=3197 had the primary outcome recorded (n=1129 physician associates, n=2068 doctor); 14 clinicians and managers and 6 patients or relatives for interview; 5 physician associates for observation. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome was unplanned re-attendance at the same emergency department within 7 days. SECONDARY OUTCOMES: consultation processes, clinical adequacy of care, and staff and patient experience. RESULTS: Re-attendances within 7 days (n=194 (6.1%)) showed no difference between physician associates and foundation year two doctors-in-training (OR 0.87, 95% CI 0.61 to 1.24, p=0.437). If seen by a physician associate, patients were more likely receive an X-ray investigation (OR 2.10, 95% CI 1.72 to 4.24), p<0.001), after adjustment for patient characteristics, triage severity of condition and statistically significant clinician intraclass correlation. Clinical reviewers found almost all patients' charts clinically adequate. Physician associates were evaluated as assessing patients in a similar way to foundation year two doctors-in-training and providing continuity in the team. Patients were positive about the care they had received from a physician associate, but had poor understanding of the role. CONCLUSIONS: Physician associates in emergency departments in England treated patients with a range of conditions safely, and at a similar level to foundation year two doctors-in-training, providing clinical operational efficiencies

    Sharks of the order Carcharhiniformes from the British Coniacian, Santonian and Campanian (Upper Cretaceous).

    Get PDF
    Bulk sampling of phosphate-rich horizons within the British Coniacian to Campanian (Upper Cretaceous) yielded very large samples of shark and ray teeth. All of these samples yielded teeth of diverse members of the Carcharhiniformes, which commonly dominate the fauna. The following species are recorded and described: Pseudoscyliorhinus reussi (Herman, 1977) comb. nov., Crassescyliorhinus germanicus (Herman, 1982) gen. nov., Scyliorhinus elongatus (Davis, 1887), Scyliorhinus brumarivulensis sp. nov., ? Palaeoscyllium sp., Prohaploblepharus riegrafi (Müller, 1989) gen. nov., ? Cretascyliorhinus sp., Scyliorhinidae inc. sedis 1, Scyliorhinidae inc. sedis 2, Pteroscyllium hermani sp. nov., Protoscyliorhinus sp., Leptocharias cretaceus sp. nov., Palaeogaleus havreensis Herman, 1977, Paratriakis subserratus sp. nov., Paratriakis tenuis sp. nov., Paratriakis sp. indet. and ? Loxodon sp. Taxa belonging to the families ?Proscylliidae, Leptochariidae, and Carcharhinidae are described from the Cretaceous for the first time. The evolutionary and palaeoecological implications of these newly recognised faunas are discussed

    The clinical application of electrical impedance technology in the detection of malignant neoplasms: a systematic review

    Get PDF
    Background: Electrical impedance technology has been well established for the last 20 years. Recently research has begun to emerge into its potential uses in the detection and diagnosis of pre-malignant and malignant conditions. The aim of this study was to systematically review the clinical application of electrical impedance technology in the detection of malignant neoplasms. Methods: A search of Embase Classic, Embase and Medline databases was conducted from 1980 to 22/02/2018 to identify studies reporting on the use of bioimpedance technology in the detection of pre-malignant and malignant conditions. The ability to distinguish between tissue types was defined as the primary endpoint, and other points of interest were also reported. Results: 731 articles were identified, of which 51 reported sufficient data for analysis. These studies covered 16 different cancer subtypes in a total of 7035 patients. As the studies took various formats, a qualitative analysis of each cancer subtype’s data was undertaken. All the studies were able to show differences in electrical impedance and/or related metrics between malignant and normal tissue. Conclusions: Electrical impedance technology provides a novel method for the detection of malignant tissue, with large studies of cervical, prostate, skin and breast cancers showing encouraging results. Whilst these studies provide promising insights into the potential of this technology as an adjunct in screening, diagnosis and intra-operative margin assessment, customised development as well as multi-centre clinical trials need to be conducted before it can be reliably employed in the clinical detection of malignant tissue

    Human metapneumovirus infection after allogeneic hematopoietic stem cell transplantation

    Get PDF
    Background: The clinical characteristics of human metapneumovirus (hMPV)-associated lower respiratory tract infection (LRTI) after allogeneic hematopoietic stem cell transplantation (HSCT) is not well described. We describe the clinical course in eight HSCT recipients suffering from hMPV infection. Methods: We prospectively included all patients with hMPV-associated LRTI after allogeneic HSCT during a period of 1year. hMPV was diagnosed by multiplex polymerase chain reaction (PCR) from bronchoalveolar lavage (BAL). Results: Eight patients with hMPV-associated LRTI were identified from 93 BAL samples. Three of the eight patients had co-infections with other pathogens. The median age of the patients was 45years [interquartile range (IQR) 36.8-53.5], the median time posttransplant was 473days (IQR 251-1,165), 5/8 patients had chronic graft-versus-host disease (cGvHD), and 6/8 patients received immunosuppression. Chest computed tomography (CT) scanning showed a ground-glass pattern in 7/8 patients. Seven of eight patients required hospitalization due to severe symptoms and hypoxemia. All were treated with intravenous immunoglobulin (IVIG), which was combined with oral ribavirin in six patients. The mortality rate was 12.5% (1/8). Conclusions: hMPV-associated LRTI in allogeneic HSCT recipients are not uncommon and present with unspecific respiratory symptoms, ground-glass pattern in CT scanning, and co-infectio

    Support and Assessment for Fall Emergency Referrals (SAFER) 2: a cluster randomised trial and systematic review of clinical effectiveness and cost-effectiveness of new protocols for emergency ambulance paramedics to assess older people following a fall with referral to community-based care when appropriate.

    Get PDF
    BACKGROUND: Emergency calls are frequently made to ambulance services for older people who have fallen, but ambulance crews often leave patients at the scene without any ongoing care. We evaluated a new clinical protocol which allowed paramedics to assess older people who had fallen and, if appropriate, refer them to community-based falls services. OBJECTIVES: To compare outcomes, processes and costs of care between intervention and control groups; and to understand factors which facilitate or hinder use. DESIGN: Cluster randomised controlled trial. PARTICIPANTS: Participating paramedics at three ambulance services in England and Wales were based at stations randomised to intervention or control arms. Participants were aged 65 years and over, attended by a study paramedic for a fall-related emergency service call, and resident in the trial catchment areas. INTERVENTIONS: Intervention paramedics received a clinical protocol with referral pathway, training and support to change practice. Control paramedics continued practice as normal. OUTCOMES: The primary outcome comprised subsequent emergency health-care contacts (emergency admissions, emergency department attendances, emergency service calls) or death at 1 month and 6 months. Secondary outcomes included pathway of care, ambulance service operational indicators, self-reported outcomes and costs of care. Those assessing outcomes remained blinded to group allocation. RESULTS: Across sites, 3073 eligible patients attended by 105 paramedics from 14 ambulance stations were randomly allocated to the intervention group, and 2841 eligible patients attended by 110 paramedics from 11 stations were randomly allocated to the control group. After excluding dissenting and unmatched patients, 2391 intervention group patients and 2264 control group patients were included in primary outcome analyses. We did not find an effect on our overall primary outcome at 1 month or 6 months. However, further emergency service calls were reduced at both 1 month and 6 months; a smaller proportion of patients had made further emergency service calls at 1 month (18.5% vs. 21.8%) and the rate per patient-day at risk at 6 months was lower in the intervention group (0.013 vs. 0.017). Rate of conveyance to emergency department at index incident was similar between groups. Eight per cent of trial eligible patients in the intervention arm were referred to falls services by attending paramedics, compared with 1% in the control arm. The proportion of patients left at scene without further care was lower in the intervention group than in the control group (22.6% vs. 30.3%). We found no differences in duration of episode of care or job cycle. No adverse events were reported. Mean cost of the intervention was £17.30 per patient. There were no significant differences in mean resource utilisation, utilities at 1 month or 6 months or quality-adjusted life-years. In total, 58 patients, 25 paramedics and 31 stakeholders participated in focus groups or interviews. Patients were very satisfied with assessments carried out by paramedics. Paramedics reported that the intervention had increased their confidence to leave patients at home, but barriers to referral included patients' social situations and autonomy. CONCLUSIONS: Findings indicate that this new pathway may be introduced by ambulance services at modest cost, without risk of harm and with some reductions in further emergency calls. However, we did not find evidence of improved health outcomes or reductions in overall NHS emergency workload. Further research is necessary to understand issues in implementation, the costs and benefits of e-trials and the performance of the modified Falls Efficacy Scale. TRIAL REGISTRATION: Current Controlled Trials ISRCTN60481756 and PROSPERO CRD42013006418. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 21, No. 13. See the NIHR Journals Library website for further project information
    corecore