1,791 research outputs found
Nominal and local stress quantities to design aluminium-to-steel thin welded joints against fatigue
Welding aluminium to steel to make mechanical joints is possible, but there is, to date, no accepted method for performing the fatigue assessment of such hybrid connections. In this context, the present investigation aims at checking the accuracy of nominal stresses, effective notch stresses, notch-stress intensity factors, and the Modified Wöhler Curve method (applied in conjunction with the Theory of Critical Distances) in estimating fatigue lifetime of butt, cruciform, lap and tee aluminium-to-steel thin welded joints. EWM coldArc® welding technology was used to manufacture the welded specimens that were used for this validation exercise. The samples being tested in the structural laboratory of the University of Sheffield, UK, were manufactured by using AA1050 aluminium and EN10130:1991 steel with main plates thicknesses of 1 mm or 2 mm. The results from this experimental/theoretical investigation demonstrate that all the design methodologies being investigated can be used to perform the fatigue assessment of aluminium-to-steel thin welded joints provided that suitable reference/calibration fatigue curves are used. In the present paper, some quantitative recommendations are given for use in situations of practical interest of the design techniques being considered
Itasca Area Community Asset Mapping Project
The Itasca Area Community Asset Map is a tool meant for youth looking for out-of-school resources, along with economic resources for families. The dataset consists of an Excel spreadsheet (.xlsx), along with a map created with the Google Maps engine. The map was created so it would be available for use by families and youth looking for out-of-school and economic resources in the Itasca area.Prepared in partnership with the United Way of 1000 Lakes by the Community Assistantship Program (CAP), which is administered by the Center for Urban and Regional Affairs (CURA) at the University of Minnesota
A Cost Analysis of Carpal Tunnel Release Surgery Performed Wide Awake versus under Sedation.
BACKGROUND: Hand surgery under local anesthesia only has been used more frequently in recent years. The purpose of this study was to compare perioperative time and cost for carpal tunnel release performed under local anesthesia ( wide-awake local anesthesia no tourniquet, or WALANT) only to carpal tunnel release performed under intravenous sedation.
METHODS: A retrospective comparison of intraoperative (operating room) surgical time and postoperative (postanesthesia care unit) time for consecutive carpal tunnel release procedures performed under both intravenous sedation and wide-awake local anesthesia was undertaken. All operations were performed by the same surgeon using the same mini-open surgical technique. A cost analysis was performed by means of standardized anesthesia billing based on base units, time, and conversion rates.
RESULTS: There were no significant differences between the two groups in terms of total operative time, 28 minutes in the intravenous sedation group versus 26 minutes in the wide-awake local anesthesia group. Postanesthesia care unit times were significantly longer in the intravenous sedation group (84 minutes) compared to the wide-awake local anesthesia group (7 minutes). Depending on conversion rates used, a total of 432 was saved in each case performed with wide-awake local anesthesia by not using anesthesia services. In addition, a range of 1613 was saved for the full episode of care, including anesthesia costs, operating room time, and postanesthesia care unit time for each patient undergoing wide-awake local anesthesia carpal tunnel release.
CONCLUSION: Carpal tunnel release surgery performed with the wide-awake local anesthesia technique offers significant reduction in cost for use of anesthesia and postanesthesia care unit resources
Behavioral outcome measures used for human neural stem cell transplantation in rat stroke models
Stroke is a leading cause of death and disability, leading to the development of various stroke models to test new treatments, most commonly in the rat. Human stroke trials focus on disability, related primarily to neurological deficits. To better model the clinical application of these treatments, many behavioral tests have been developed using the rat stroke model. We performed a systematic review of all the behavioral outcome measures used in published studies of human neural stem cell transplantation in rat stroke models. The reviewed tests include motor, sensory, cognitive, activity, and combination tests. For each test, we give a brief description, trace the origin of the test, and discuss test performance in the reviewed studies. We conclude that while many behavioral tests are available for this purpose, there does not appear to be consensus on an optimal testing strategy
Benchmarking Gas Path Diagnostic Methods: A Public Approach
Recent technology reviews have identified the need for objective assessments of engine health management (EHM) technology. The need is two-fold: technology developers require relevant data and problems to design and validate new algorithms and techniques while engine system integrators and operators need practical tools to direct development and then evaluate the effectiveness of proposed solutions. This paper presents a publicly available gas path diagnostic benchmark problem that has been developed by the Propulsion and Power Systems Panel of The Technical Cooperation Program (TTCP) to help address these needs. The problem is coded in MATLAB (The MathWorks, Inc.) and coupled with a non-linear turbofan engine simulation to produce "snap-shot" measurements, with relevant noise levels, as if collected from a fleet of engines over their lifetime of use. Each engine within the fleet will experience unique operating and deterioration profiles, and may encounter randomly occurring relevant gas path faults including sensor, actuator and component faults. The challenge to the EHM community is to develop gas path diagnostic algorithms to reliably perform fault detection and isolation. An example solution to the benchmark problem is provided along with associated evaluation metrics. A plan is presented to disseminate this benchmark problem to the engine health management technical community and invite technology solutions
The complexities of electronic services implementation and institutionalisation in the public sector
This is the post-print version of the final paper published in Information & Management. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2013 Elsevier B.V.Electronic service implementation (ESI) in the public sector attempts to improve efficiency, effectiveness, and transparency of governmental departments. Despite having provided the necessary infrastructure and investment, many governments have struggled to realise such aims due to the various forces that challenge implementation and institutionalisation. Using institutional theory as a lens, we explored the forces influencing the implementation and institutionalisation of ESI in the public sector. While our results reinforced previous research in IT implementation and organisational transformation, they showed that the dynamic nature of technology poses unanticipated pressures, and that these can impede the implementation and institutionalisation process
On the biological and genetic diversity in Neospora caninum
Published: 22 March 2010Neospora caninum is a parasite regarded a major cause of foetal loss in cattle. A key requirement to an understanding of the epidemiology and pathogenicity of N. caninum is knowledge of the biological characteristics of the species and the genetic diversity within it. Due to the broad intermediate host range of the species, worldwide geographical distribution and its capacity for sexual reproduction, significant biological and genetic differences might be expected to exist. N. caninum has now been isolated from a variety of different host species including dogs and cattle. Although isolates of this parasite show only minor differences in ultrastructure, considerable differences have been reported in pathogenicity using mainly mouse models. At the DNA level, marked levels of polymorphism between isolates were detected in mini- and microsatellites found in the genome of N. caninum. Knowledge of what drives the biological differences that have been observed between the various isolates at the molecular level is crucial in aiding our understanding of the epidemiology of this parasite and, in turn, the development of efficacious strategies, such as live vaccines, for controlling its impact. The purpose of this review is to document and discuss for the first time, the nature of the diversity found within the species Neospora caninum.Sarwat E. Al-Qassab, Michael P. Reichel and John T. Elli
Discovery and validation of cell cycle arrest biomarkers in human acute kidney injury
Introduction
Acute kidney injury (AKI) can evolve quickly and clinical measures of function often fail to detect AKI at a time when interventions are likely to provide benefit. Identifying early markers of kidney damage has been difficult due to the complex nature of human AKI, in which multiple etiologies exist. The objective of this study was to identify and validate novel biomarkers of AKI. Methods
We performed two multicenter observational studies in critically ill patients at risk for AKI - discovery and validation. The top two markers from discovery were validated in a second study (Sapphire) and compared to a number of previously described biomarkers. In the discovery phase, we enrolled 522 adults in three distinct cohorts including patients with sepsis, shock, major surgery, and trauma and examined over 300 markers. In the Sapphire validation study, we enrolled 744 adult subjects with critical illness and without evidence of AKI at enrollment; the final analysis cohort was a heterogeneous sample of 728 critically ill patients. The primary endpoint was moderate to severe AKI (KDIGO stage 2 to 3) within 12 hours of sample collection. Results
Moderate to severe AKI occurred in 14% of Sapphire subjects. The two top biomarkers from discovery were validated. Urine insulin-like growth factor-binding protein 7 (IGFBP7) and tissue inhibitor of metalloproteinases-2 (TIMP-2), both inducers of G1 cell cycle arrest, a key mechanism implicated in AKI, together demonstrated an AUC of 0.80 (0.76 and 0.79 alone). Urine [TIMP-2]·[IGFBP7] was significantly superior to all previously described markers of AKI (P \u3c0.002), none of which achieved an AUC \u3e0.72. Furthermore, [TIMP-2]·[IGFBP7] significantly improved risk stratification when added to a nine-variable clinical model when analyzed using Cox proportional hazards model, generalized estimating equation, integrated discrimination improvement or net reclassification improvement. Finally, in sensitivity analyses [TIMP-2]·[IGFBP7] remained significant and superior to all other markers regardless of changes in reference creatinine method. Conclusions
Two novel markers for AKI have been identified and validated in independent multicenter cohorts. Both markers are superior to existing markers, provide additional information over clinical variables and add mechanistic insight into AKI. Trial registration
ClinicalTrials.gov number NCT01209169
Oxidative dearomatisation: the key step of sorbicillinoid biosynthesis
An FAD-dependent monooxygenase encoding gene (SorbC) was cloned from Penicillium chrysogenum E01-10/3 and expressed as a soluble protein in Escherichia coli. The enzyme efficiently performed the oxidative dearomatisation of sorbicillin and dihydrosorbicillin to give sorbicillinol and dihydrosorbicillinol respectively. Bioinformatic examination of the gene cluster surrounding SorbC indicated the presence of two polyketide synthase (PKS) encoding genes designated sorbA and sorbB. The gene sorbA-encodes a highly reducing iterative PKS while SorbB encodes a non-reducing iterative PKS which features a reductive release domain usually involved in the production of polyketide aldehydes. Using these observations and previously reported results from isotopic feeding experiments a new and simpler biosynthetic route to the sorbicillin class of secondary metabolites is proposed which is consistent with all reported experimental results.Al Baha University, Saudi ArabiaEP/F066104/1BB/I003355/1BMBFERASMUS programm
When study site contributes to outcomes in a multi-center randomized trial: a secondary analysis of decisional conflict in men with localized prostate cancer
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