826 research outputs found
SeniorenlÀufer werden schneller und gewinnen Ultramarathons
Quintessenz
âą Seniorensportler (LĂ€ufer ĂŒber 35 Jahre) dominieren Ultramarathons, also LĂ€ufe, die lĂ€nger sind als die klassische Marathondistanz von 42,195 km.
âą Aus physiologischer Sicht wird mit ca. 35 Jahren der Leistungszenit im Langstrecken-Laufsport ĂŒberschritten.
âą Das Alter der Spitzenleistung im Ultralaufen steigt mit zunehmender Distanz und/oder der Dauer eines Ultramarathons.
âą Lebenslanger Ausdauersport vermindert die altersbedingte Abnahme der maximalen Sauerstoffaufnahme um ca. 50%.
⹠Eine Abnahme der Muskelmasse ist kein unabwendbares Schicksal, denn regelmÀssiges Training lÀsst den altersbedingten jÀhrlichen Abbau auf bis zu 0,5% schrumpfen
The anterior center edge angle in Lequesne's false profile view: interrater correlation, dependence on pelvic tilt and correlation to anterior acetabular coverage in the sagital plane. A cadaver study
Introduction: Lequesne's vertical-center-anterior margin (VCA) angle measured on the false profile view of the pelvis aims at quantifying the anterior acetabular coverage of the femoral head. The anterior delimitation of the acetabular roof is often defined on the false profile view but there are no data on its interrater reliability. Additionally, it is not known how pelvic tilt may influence this angle. Finally, the plane in which this angle is measured lies at an angle of 65° to the sagittal plane and we wondered if this angle would be transposable to the anterior acetabular coverage measured in the sagittal plane. Methods: Eight hips from four cadaver pelvises were investigated by means of a total of 72 false profile views, each taken in defined pelvic inclinations at 5° increments ranging from â20° to +20°, and the VCA angle measured by three independent raters. A computed tomography (CT) of each hip was performed in a neutral pelvic tilt position and a sagittal 2D reconstruction calculated in order to measure anterior coverage in the sagittal plane. The interrater reliability of the VCA angles was assessed using the intra-class correlation coefficient (ICC). The dependence of the VCA angle on pelvic tilt was assessed by regression analysis. The Correlation between the VCA angle and anterior coverage in the sagittal plane of the CT was analyzed using a simple linear regression model. Results: The interrater reliability for measurements of the VCA angle was almost perfect (ICC:0.97). Regression analysis showed that each degree of pelvic tilt was accompanied by a change of the VCA angle by a value of 0.63° (P<0.001). A low correlation between the VCA angle measured in the false profile view and the anterior coverage in the sagittal plane was statistically not significant (r=0.667, P=0.06). Conclusions: Lequesne's VCA angle has an excellent interrater reliability and represents a reliable measure of acetabular dysplasia for comparisons with published data. Lequesne's VCA angle is influenced by pelvic tilt in a linear manner. Performing the false profile view in a standing position may reduce the clinical relevance of this dependency on pelvic tilt. The correlation of Lequesne's VCA angle to anterior acetabular coverage in the sagittal plane is low and therefore unsuitable to be transposed into the sagittal plan
The evolution of pebble size and shape in space and time
We propose a mathematical model which suggests that the two main geological
observations about shingle beaches, i.e. the emergence of predominant pebble
size ratios and strong segregation by size are interrelated. Our model is a
based on a system of ODEs called the box equations, describing the evolution of
pebble ratios. We derive these ODEs as a heuristic approximation of Bloore's
PDE describing collisional abrasion. While representing a radical
simplification of the latter, our system admits the inclusion of additional
terms related to frictional abrasion. We show that nontrivial attractors
(corresponding to predominant pebble size ratios) only exist in the presence of
friction. By interpreting our equations as a Markov process, we illustrate by
direct simulation that these attractors may only stabilized by the ongoing
segregation process.Comment: 22 pages, 8 figure
Earthquake Resistance of a Rockfill Dam
The paper describes the investigation of the seismic safety of a 131 m high rock fill dam presently under construction across the Rio Chixoy in Guatemala. The dam is located in a region of high seismicity the recently active Motagua fault being only 40 km distant. Due to the possibility of high peak ground accelerations it was considered necessary to conduct a full dynamic analysis, which was carried out in stages following the Seed-Lee-Idriss method, the latter being modified where it was deemed necessary
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Implementation research for the prevention of antimicrobial resistance and healthcare-associated infections; 2017 Geneva infection prevention and control (IPC)-think tank (part 1)
Background
Around 5â15% of all hospital patients worldwide suffer from healthcare-associated infections (HAIs), and years of excessive antimicrobial use in human and animal medicine have created emerging antimicrobial resistance (AMR). A considerable amount of evidence-based measures have been published to address these challenges, but the largest challenge seems to be their implementation.
Methods
In June 2017, a total of 42 experts convened at the Geneva IPC-Think Tank to discuss four domains in implementation science: 1) teaching implementation skills; 2) fostering implementation of IPC and antimicrobial stewardship (AMS) by policy making; 3) national/international actions to foster implementation skills; and 4) translational research bridging social sciences and clinical research in infection prevention and control (IPC) and AMR.
Results
Although neglected in the past, implementation skills have become a priority in IPC and AMS. They should now be part of any curriculum in health care, and IPC career paths should be created. Guidelines and policies should be aligned with each other and evidence-based, each document providing a section on implementing elements of IPC and AMS in patient care. International organisations should be advocates for IPC and AMS, framing them as patient safety issues and emphasizing the importance of implementation skills. Healthcare authorities at the national level should adopt a similar approach and provide legal frameworks, guidelines, and resources to allow better implementation of patient safety measures in IPC and AMS. Rather than repeating effectiveness studies in every setting, we should invest in methods to improve the implementation of evidence-based measures in different healthcare contexts. For this, we need to encourage and financially support collaborations between social sciences and clinical IPC research.
Conclusions
Experts of the 2017 Geneva Think Tank on IPC and AMS, CDC, and WHO agreed that sustained efforts on implementation of IPC and AMS strategies are required at international, country, and hospital management levels, to provide an adequate multimodal framework that addresses (not exclusively) leadership, resources, education and training for implementing IPC and AMS. Future strategies can build on this agreement to make strategies on IPC and AMS more effective
Komplexe proximale Humerusfraktur beim alten Menschen: Winkelstabile Plattenosteosynthese vs. Hemiarthroplastik
Zusammenfassung: Hintergrund: Ziel der vorliegenden Untersuchung ist ein direkter Vergleich der Schulterhemiarthroplastik (SHA) mit der winkelstabilen Plattenosteosynthese (WSPOS) beim alten Patienten mit komplexer proximaler Humerusfraktur. Patienten und Methoden: Zwischen 2003 und 2005 wurden alle Patienten (n=52, Alter â„70Jahre) mit 3- und 4-Segment-Frakturen des proximalen Humerus, welche mit einer WSPOS (PHILOSÂź) versorgt wurden, prospektiv erfasst und nach einem Jahr mittels Constant-Score (CS), Oxford Shoulder Score (OSS) und radiologisch nachkontrolliert. Verglichen wurde die WSPOS mit einem historischen Kollektiv mit identischen Einschlusskriterien, welches zwischen 1995 und 1997 an der gleichen Institution mittels SHA versorgt wurde (n=59). Ergebnisse: Beide Patientenkollektive zeigten keine Unterschiede bezĂŒglich Alter, Geschlechterverteilung und Frakturtypen. Der CS war signifikant besser fĂŒr die WSPOS (median 71 vs. 41). BezĂŒglich Schmerzen zeigte sich im OSS kein Unterschied zwischen den Gruppen. In der WSPOS-Gruppe mussten signifikant mehr Revisionseingriffe durchgefĂŒhrt werden (25% vs. 2%). Schlussfolgerung: Die WSPOS liefert beim alten Patienten, bei komplexen proximalen Humerusfrakturen deutlich bessere funktionelle Resultate, ist jedoch mit mehr Rezidiveingriffen behaftet. Die SelbstĂ€ndigkeit der Patienten kann bei beiden Operationsmethoden bei guter Schmerzfreiheit meist erhalten werde
Effect of bisacodyl on postoperative bowel motility in elective colorectal surgery: a prospective, randomized trial
Background: Postoperative ileus is a common condition after abdominal surgery. Many prokinetic drugs have been evaluated including osmotic laxatives. The data on colon-stimulating laxatives are scarce. This prospective, randomized, double-blind trial investigates the effect of the colon-stimulating laxative bisacodyl on postoperative ileus in elective colorectal resections. Materials and methods: Between November 2004 and February 2007, 200 consecutive patients were randomly assigned to receive either bisacodyl or placebo. Primary endpoint was time to gastrointestinal recovery (mean time to first flatus passed, first defecation, and first solid food tolerated; GI-3). Secondary endpoints were incidence and duration of nasogastric tube reinsertion, incidence of vomiting, length of hospital stay, and visual analogue scores for pain, cramps, and nausea. Results: One hundred sixty-nine patients were analyzed, and 31 patients discontinued the study. Groups were comparable in baseline demographics. Time to GI-3 was significantly shorter in the bisacodyl group (3.0 versus 3.7days, Pâ=â0.007). Of the single parameters defining GI-3, there was a 1-day difference in time to defecation in favor to the bisacodyl group (3.0 versus 4.0days, Pâ=â0.001), whereas no significant difference in time to first flatus or tolerance of solid food was seen. No significant difference in the secondary endpoints was seen. Morbidity and mortality did not differ between groups. Conclusion: Bisacodyl accelerated gastrointestinal recovery and might be considered as part of multimodal recovery programs after colorectal surger
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