Implant augmentation: Adding bone cement to improve the treatment of osteoporotic distal femur fractures:A biomechanical study using human cadaver bones

The increasing problems in the field of osteoporotic fracture fixation results in specialized implants as well as new operation methods, for example, implant augmentation with bone cement. The aim of this study was to determine the biomechanical impact of augmentation in the treatment of osteoporotic distal femur fractures. Seven pairs of osteoporotic fresh frozen distal femora were randomly assigned to either an augmented or nonaugmented group. In both groups, an Orthopaedic Trauma Association 33 A3 fractures was fixed using the locking compression plate distal femur and cannulated and perforated screws. In the augmented group, additionally, 1 mL of polymethylmethacrylate cement was injected through the screw. Prior to mechanical testing, bone mineral density (BMD) and local bone strength were determined. Mechanical testing was performed by cyclic axial loading (100 N to 750 N + 0.05N/cycle) using a servo-hydraulic testing machine. As a result, the BMD as well as the axial stiffness did not significantly differ between the groups. The number of cycles to failure was significantly higher in the augmented group with the BMD as a significant covariate. In conclusion, cement augmentation can significantly improve implant anchorage in plating of osteoporotic distal femur fractures

Changes in union membership over time : a panel analysis for West Germany

Despite the apparent stability of the wage bargaining institutions in West Germany, aggregate union membership has been declining dramatically since the early 90's. However, aggregate gross membership numbers do not distinguish by employment status and it is impossible to disaggregate these sufficiently. This paper uses four waves of the German Socioeconomic Panel in 1985, 1989, 1993, and 1998 to perform a panel analysis of net union membership among employees. We estimate a correlated random effects probit model suggested in Chamberlain (1984) to take proper account of individual specfic effects. Our results suggest that at the individual level the propensity to be a union member has not changed considerably over time. Thus, the aggregate decline in membership is due to composition effects. We also use the estimates to predict net union density at the industry level based on the IAB employment subsample for the time period 1985 to 1997. JEL - Klassifikation: J

ПРО ОДИН З АСПЕКТІВ КОМПЛЕКСНОГО ВИРІШЕННЯ ПИТАННЯ БУДІВНИЦТВА КАНАЛУ АЗОВСЬКЕ МОРЕ – МОЛОЧНИЙ ЛИМАН

Молочний лиман – один з найбільш цінних водно-болотних угідь Приа-зов’я, який увійшов до Міжнародного кадастру Рамсарських територій. Згідно з фізико-географічним районуванням України, Молочний лиман відноситься до Присивасько-Приазовської степової області Причорноморської південно-степової провінції. Адміністративно ця акваторія знаходиться в Запорізькій об-ласті і розташована на територіях Якимівського, Приазовського та Мелітополь-ського районів. Довжина лиману складає 32 км, максимальна ширина 8 км, гли-бина до 3 м, площа 170 км2. Від Азовського моря Лиман відділений косою Пе-ресип зі штучно створеною протокою (промоїною). Останнім часом, з`єднувальний канал Молочного лиману практично не функціонує

The Evolution of the German Corporate Network (1896-1933)

This article provides a structural analysis of corporate interlocks in Germany at the beginning of the 20th century. The main goal is, first, to point out that dense interlocking goes along with a socio-economic concentration process originating in the German Empire, and is freezing as a proved institutional solution during the Weimar Republic (Abelshauser, 2005; Streeck et al., 2001). Second, a special contribution is to highlight the mechanism behind the network evolution: multiple interlocking of preferred actors, thus, creating a core-periphery structured network. Reconstruction of social forces behind these patterns provides an insight into the diverse opportunity structure gained by core corporations. Results demonstrate that the German variety of economic modernization was not only a macro-phenomenon as aggregation would indicate. Actors were quite differently guided by these macro signals. The specific structure of German interlocks is due to selection processes at the micro-level which finally created a hegemonic network different than expected

Changes in Union Membership Over Time : A Panel Analysis for West Germany

Despite the apparent stability of the wage bargaining institutions in West Germany, aggregate union membership has been declining dramatically since the early 90's. However, aggregate gross membership numbers do not distinguish by employment status and it is impossible to disaggregate these su±ciently. This paper uses four waves of the German Socioeconomic Panel in 1985, 1989, 1993, and 1998 to perform a panel analysis of net union membership among employees. We estimate a correlated random effects probit model suggested in Chamberlain (1984) to take proper account of individual specific effects. Our results suggest that at the individual level the propensity to be a union member has not changed considerably over time. Thus, the aggregate decline in membership is due to composition effects. We also use the estimates to predict net union density at the industry level based on the IAB employment subsample for the time period 1985 to 1997

Networks of corporate power revisited

This paper examines developments through the quarter century since the publication of Stokman, Ziegler and Scott's (1985) iconic ten-nation study of the structure of interlocking directorships. The surprising decline of research in the area following the publication of Networks of Corporate Power is in part testimony to the rigour of the comparative methods used, raising the standard of evidence required for subsequent director interlock studies. But it also reflected a critical weakness in director interlock research to that point, the limited ability to answer what Mark Mizruchi has called the “So what?” question. While replicated studies found clear structures in director interlocks, varying from country to country, and there was some speculative fit with the distinctive political economies of these countries, there was little evidence of any effect of these structures on firm performance or activity. The more recent resurgence in director interlock research is in some ways rooted in a second generation of the original drivers; the ready availability of now large masses of data on firm governance and firm level performance and further advances in social network analytical techniques. Where Stokman and his colleagues manually compiled lists of directors scoured from company reports, these data are now routinely collected and compiled in accessible databases by government agencies and business information services in many countries. And there has been a gradual accumulation of advances in addressing the “so what” question

A Service Perspective on Designing Learning Companions as Bonding and Mindful Time Managers in Further Education

Further education students who work in parallel are particularly exposed to challenges such as overscheduling and exhaustion. Learning Companions (LCs) in their role as virtual relationship-oriented chatbots or voicebots in education might facilitate the burden of learning through valuable interactions. Our contribution derives design knowledge for LCs as mindful time managers from a service-oriented perspective along the three layers of the value in interaction (ViU) model. By synthesizing the findings of a systematic literature review and user needs from six qualitative interviews with the target group, we derive 24 design requirements and iteratively synthesize five design principles emerging from the evaluation of a low-fidelity prototype. On a meta-level, we intend to contextualize a value-driven, service-oriented perspective on the design of information systems such as LCs

De la cohésion à la dissolution

À la fin du xixe siècle, on a vu se développer, parallèlement à l’émergence du capitalisme managérial, un réseau reliant les grandes sociétés anonymes – réseau créé par des directeurs occupant alors plusieurs postes à responsabilité dans différentes entreprises (big linkers). Un tel réseau offre notamment la chance de coordonner les stratégies des entreprises et de contraindre les membres à des standards éthiques communs. Par une analyse comparative de la structure du réseau des grandes entreprises en Allemagne, en France et aux États-Unis pour la période 1900-2010, cet article met en évidence qu’en Allemagne la densité du réseau est particulièrement élevée pendant l’entre-deux-guerres et que le réseau se dissout entre 1995 et 2010. La densité, dans les trois pays, est alors inférieure au niveau atteint en 1900. À la fin de la période qui constitue l’objet de notre analyse, il n’y a plus de différence nationale relativement à la densité des réseaux.In the late 19th century, alongside the emergence of managerial capitalism, dense networks arose linking major corporations and the financial sector. These networks were created by executives who held different senior positions in many large corporations (big linkers). Such corporate networks served several purposes, such as to coordinate corporate strategies and hold members to the same ethical standards. Through a comparative analysis of the network structure of large corporations in Germany, France and the United States from 1900 to 2010, this article points up that the network in Germany was particularly dense in the inter-war period and that network density declined substantially between 1995 and 2010, when the level in all three countries fell below the level of 1900. By 2010, there was no longer any difference in network density between Germany, France and the United States