Effect of ski boot rear stiffness (SBRS) on maximal ACL force during injury prone landing movements in alpine ski racing: A study with a musculoskeletal simulation model

A common anterior cruciate ligament (ACL) injury situation in alpine ski racing is landing back-weighted after a jump. Simulated back-weighted landing situations showed higher ACL-injury risk for increasing ski boot rear stiffness (SBRS) without considering muscles. It is well known that muscle forces affect ACL tensile forces during landing. The purpose of this study is to investigate the effect of different SBRS on the maximal ACL tensile forces during injury prone landings considering muscle forces by a two-dimensional musculoskeletal simulation model. Injury prone situations for ACL-injuries were generated by the musculoskeletal simulation model using measured kinematics of a non-injury situation and the method of Monte Carlo simulation. Subsequently, the SBRS was varied for injury prone landings. The maximal ACL tensile forces and contributing factors to the ACL forces were compared for the different SBRS. In the injury prone landings the maximal ACL tensile forces increased with increasing SBRS. It was found that the higher maximal ACL force was caused by higher forces acting on the tibia by the boot and by higher quadriceps muscle forces both due to the higher SBRS. Practical experience suggested that the reduction of SBRS is not accepted by ski racers due to performance reasons. Thus, preventive measures may concentrate on the reduction of the quadriceps muscle force during impact.     

Program Assessments: Success Strategies for Three Canadian Teaching Centers

Program assessments are an essential part of the ongoing survival of teaching centers performed by faculty development personnel at institutions of higher education. Little research is available to guide developers in performing these assessments. In this article we describe assessments conducted at three Canadian universities and highlight the theoretical models used to guide the process. Reflections on the strengths and challenges are discussed for each program assessment for the purpose of assisting faculty developers in performing similar program assessments of their faculty development offices.

Validierung von neun Bewegungssensoren bei Kindern und jungen Erwachsenen

The purpose of this study was to determine the accuracy of one accelerometer and eight pedometers in schoolchildren and young adults under controlled experimental conditions and under free-living conditions over a 24-h period. The most accurate results under controlled conditions were obtained with a piezoelectric pedometer. For this device absolute deviations (median) ranged between 0.2 and 1.0% for children and between 0.2 and 1.4% for young adults. Absolute deviations for the accelerometer were 0.8–3.1% for children and 0.6–3.2% for adults. Motion sensors were more accurate with increasing walking speed. For several pedometers the absolute deviation exceeded 50% in tests with schoolchildren. These differing results illustrate that step counts from different motion sensors cannot be compared directly. Therefore, the validity and reliability of activity monitors should be examined carefully before being used in scientific research.     

AEG-Telefunken TR 440: Unternehmensstrategie, Markterfolg und Nachfolger

Zusammenfassung  AEG-Telefunken entwickelte seit 1957 Rechner. Neben den Prozessrechnern spielten die Gro?rechner TR 4 und TR 440 eine wichtige Rolle. Von 1969 bis 1976 wurden 46 TR 440 installiert, bei einem Gesamtumsatz von 730 Mio. DM (370 Mio. Euro) [2]. In der Produktpolitik spielten die Rechner keine zentrale Rolle, obwohl eine ausgezeichnete technologische Ausgangsposition bestanden hatte und die Telefunkenrechner sp?ter nachdrückliche technologiepolitische Unterstützung erhielten. Die Entwicklung des Systems TR 440 hatte mit wesentlichen konzeptionellen und technologischen Schwierigkeiten zu k?mpfen, wozu der Mangel an qualifizierten Zulieferern und erfahrenen Mitabeitern kam. Trotzdem gelang es, bis 1970 den bislang schnellsten in Europa entwickelten Rechner [6] fertig zu stellen und Systemsoftware zu entwickeln [9], die den Produkten der Mitbewerber um Jahre voraus war. Von Anfang an hatte das Unternehmen nach geeigneten Kooperationspartnern gesucht. Mit dem Verkauf des Gro?rechnergesch?ftes an Siemens gingen die bereits laufenden Planungen für einen TR 440-Nachfolger zu Ende.

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AEG-Telefunken developed computers since 1957. Besides process control computers, the large scale computers, TR 4 and TR 440, played an important role. 46 TR 440 computers were installed from 1969 to 1976, summing up to a sales volume of 730 Mio. DM (370 Mio. Euro) [2]. AEG-Telefunken did not consider computers as a strategic part of its product policy, though the company had had an excellent technological position for this business and the Telefunken computers got vigorous political support. The development of the TR 440 system had to defeat essential conceptual and technological difficulties, besides lack of qualified suppliers and experienced personnel. Nevertheless, the company could, by 1970, develop the fastest European computer so far [6], with system software ahead of competitors by years [9]. From the beginning, the company had been looking for business partners. With the sale of the large scale computer business to Siemens, all activities on a TR 440 successor were stopped. AEG-Telefunken computer business strategy is also subject of a paper to appear in the IEEE Annals of the History of Computing.

     

Parenting behavior and the risk of becoming a victim and a bully/victim: A meta-analysis study

Objective

Being bullied has adverse effects on children's health. Children's family experiences and parenting behavior before entering school help shape their capacity to adapt and cope at school and have an impact on children's peer relationship, hence it is important to identify how parenting styles and parent–child relationship are related to victimization in order to develop intervention programs to prevent or mitigate victimization in childhood and adolescence.

Methods

We conducted a systematic review of the published literature on parenting behavior and peer victimization using MEDLINE, PsychINFO, Eric and EMBASE from 1970 through the end of December 2012. We included prospective cohort studies and cross-sectional studies that investigated the association between parenting behavior and peer victimization.

Results

Both victims and those who both bully and are victims (bully/victims) were more likely to be exposed to negative parenting behavior including abuse and neglect and maladaptive parenting. The effects were generally small to moderate for victims (Hedge's g range: 0.10–0.31) but moderate for bully/victims (0.13–0.68). Positive parenting behavior including good communication of parents with the child, warm and affectionate relationship, parental involvement and support, and parental supervision were protective against peer victimization. The protective effects were generally small to moderate for both victims (Hedge's g: range: −0.12 to −0.22) and bully/victims (−0.17 to −0.42).

Conclusions

Negative parenting behavior is related to a moderate increase of risk for becoming a bully/victim and small to moderate effects on victim status at school. Intervention programs against bullying should extend their focus beyond schools to include families and start before children enter school.     

Teaching philosophies reconsidered:A conceptual model for the development and evaluation of teaching philosophy statements

Increasingly, the requirements of applicants to academic faculty positions, promotion and tenure procedures, nominations for teaching awards, or other application processes for innovative teaching grants worldwide include a teaching portfolio or dossier or a statement of teaching philosophy. Current literature provides a spectrum of approaches to constructing a teaching philosophy statement. While these resources provide practical utility, this literature generally lacks conceptual models that provide clear operational definitions and comprehensive frameworks for the process of generating or evaluating a teaching philosophy statement. However, this literature does illustrate the complexity of the task. Each teaching philosophy statement reflects not only personal beliefs about teaching and learning, but also disciplinary cultures, institutional structures and cultures, and stakeholder expectations as well. This synergy among self, discipline, and institutional context guided the development of a conceptual model for constructing a teaching philosophy statement. Based on the authors' survey of the literature, a conceptual model was developed, and then refined in a series of three workshops that included input from graduate students, academic faculty, faculty developers, and academic managers (administrators). The resulting conceptual framework includes the six dimensions commonly found in a survey of faculty teaching philosophies: the purpose of teaching and learning; the role of the teacher; the role of the student; the methods used; evaluation and assessment of teaching and learning; and also includes two framing devices - a metaphor or a critical incident and a device for acknowledging the impact that contextual factors have on teacher decision making. This paper describes the development of this conceptual model, and provides an evaluation rubric that can be applied to assess teaching philosophy statements generated using the proposed framework.