Elastic deformations of the rotary double motor of single F(o)F(1)-ATP synthases detected in real time by Förster resonance energy transfer.

Elastic conformational changes of the protein backbone are essential for catalytic activities of enzymes. To follow relative movements within the protein, Förster-type resonance energy transfer (FRET) between two specifically attached fluorophores can be applied. FRET provides a precise ruler between 3 and 8nm with subnanometer resolution. Corresponding submillisecond time resolution is sufficient to identify conformational changes in FRET time trajectories. Analyzing single enzymes circumvents the need for synchronization of various conformations. F(O)F(1)-ATP synthase is a rotary double motor which catalyzes the synthesis of adenosine triphosphate (ATP). A proton-driven 10-stepped rotary F(O) motor in the Escherichia coli enzyme is connected to a 3-stepped F(1) motor, where ATP is synthesized. To operate the double motor with a mismatch of step sizes smoothly, elastic deformations within the rotor parts have been proposed by W. Junge and coworkers. Here we extend a single-molecule FRET approach to observe both rotary motors simultaneously in individual F(O)F(1)-ATP synthases at work. We labeled this enzyme with two fluorophores specifically, that is, on the ε- and c-subunits of the two rotors. Alternating laser excitation was used to select the FRET-labeled enzymes. FRET changes indicated associated transient twisting within the rotors of single enzyme molecules during ATP hydrolysis and ATP synthesis. Supported by Monte Carlo simulations of the FRET experiments, these studies reveal that the rotor twisting is greater than 36° and is largely suppressed in the presence of the rotation inhibitor DCCD. This article is part of a Special Issue entitled: 17th European Bioenergetics Conference (EBEC 2012)

Altersvorsorge im internationalen Vergleich: Staatliche Produkte für die zusätzliche Altersvorsorge in Schweden und dem Vereinigten Königreich

Die Kurzexpertise stellt aus sozio-ökonomischer und juristischer Sicht die zusätzlichen Altersvorsorgesysteme in Schweden und im Vereinigten Königreich dar. In Schweden wird die obligatorische kapitalgedeckte Säule zentral im Rahmen der staatlichen Rentenversicherung organisiert; Anlageentscheidungen obliegen dem Versicherten bzw. werden im Default-Fall unabhängig von staatlichem Einfluss gefällt. Die Versicherten haben zwar ein breites Spektrum von Wahlmöglichkeiten; empirisch dominiert der Default-Fonds. In Schweden sind nach Angaben der OECD zudem neunzig Prozent der Arbeitnehmer in ein tarifvertraglich begründetes Betriebsrentensystem eingebunden. Im Vereinigten Königreich wird die kapitalgedeckte Säule dagegen nur als Betriebsrente organisiert. Arbeitgeber müssen eine Betriebsrente anbieten; Arbeitnehmer werden automatisch einbezogen, können dies aber per "opt-out" ablehnen

Trends in mortality by labour market position around retirement ages in three European countries with different welfare regimes

<p>Objectives: In the face of economic downturn and increasing life expectancy, many industrial nations are adopting a policy of postponing the retirement age. However, questions still remain around the consequence of working longer into old age. We examine mortality by work status around retirement ages in countries with different welfare regimes; Finland (social democratic), Turin (Italy; conservative), and England and Wales (liberal).</p> <p>Methods: Death rates and rate ratios (RRs) (reference rates = ‘in-work’), 1970 s–2000 s, were estimated for those aged 45–64 years using the England and Wales longitudinal study, Turin longitudinal study, and the Finnish linked register study.</p> <p>Results: Mortality of the not-in-work was consistently higher than the in-work. Death rates for the not-in-work were lowest in Turin and highest in Finland. Rate ratios were smallest in Turin (RR men 1972–76 1.73; 2002–06 1.63; women 1.22; 1.68) and largest in Finland (RR men 1991–95 3.03; 2001–05 3.80; women 3.62; 4.11). Unlike RRs for men, RRs for women increased in every country (greatest in Finland).</p> <p>Conclusions: These findings signal that overall, employment in later life is associated with lower mortality, regardless of welfare regime.</p&gt

Age, retirement and health as factors in volunteering in later life

Volunteering in later life attracts attention because its benefits older volunteers, voluntary associations, and society. Unfortunately, researchers and practitioners struggle with the complexity of predicting who volunteers. The authors ask whether a rough identification of older volunteers solely based on age is possible. The authors answer this question by means of structural equation modeling, analyzing international survey data. The findings show that the direct effect of age on the time older people spend volunteering is negligible. Moreover, the age patterns in volunteering created by retirement and declining health are weak. Those findings make age an unsuitable indicator for volunteering in later life. The authors recommend that voluntary organizations and policy makers use personal characteristics, such as health status, when defining their target groups for programs that encourage volunteering. In addition, researchers should not use an age group when referring to the third age, meaning the active and productive part of old age

A promising approach in comparative research on care for the elderly

Long-term care (LTC) in the form of care provided in nursing homes, homes for the aged and home care is considered an appropriate answer to the growing needs of the aging populations of the industrialized world. However, the provision of and expenditures on LTC vary considerably between these industrialized countries. Although one would expect LTC to be subject to many internationally comparative studies, including all European countries, this is not the case. A paper presented by Damiani et al. in BMC Health Services Research contains an internationally comparative model regarding the development of LTC in Europe (2003 to 2007). They achieve an intriguing compromise between depth and width in the sparsely populated domain of internationally comparative research on LTC by characterizing countries' LTC and interpreting the large north/south differences found. Their results also show that 'cash for care' schemes form a substantial alternative to traditional LTC provision. An additional time series analysis showed that many countries seem to be engaged in reorganizing the LTC sector. This study widens knowledge in a neglected area of health services research and should serve as a source of inspiration for further studies

The Effect of Online and Mixed-Mode Measurement of Cognitive Ability

A number of studies, particularly longitudinal surveys, are collecting direct measures of cognitive ability, given its importance as a measure in social science research. As longitudinal studies increasingly switch to mixed-mode data collection, frequently including a web component, differences in survey outcomes including cognitive ability may result from mode effects. Differences may arise due to respondent self-selection into mode or due to the mode causing differential measurement. Using a longitudinal survey that measured cognitive ability after introducing a mixed-mode design with a web component, this research explores if and how mode affects cognitive ability outcomes. This survey allows for control of several possible selection mechanisms, including a limited set of direct cognitive ability measures collected in a single mode in an earlier wave. Findings presented here show clearly that web respondents do better on a number of cognitive ability indicators. However, it does not appear that this is wholly explainable by respondents of different ability self-selecting into particular modes. Rather, it appears that measurement of cognitive ability may differ across modes. This result is potentially problematic as comparability is a key component of using cognitive ability in further research

Eastern partnership migrants in Germany: outcomes, potentials and challenges

Despite the ongoing dialogue on facilitating mobility between the European Union and the Eastern Partnership (EaP) countries, very little is known about the magnitude and characteristics of migration from these countries. We find that EaP migrants experience worse labor market outcomes than other migrant groups, but current and potential migrants hold qualifications in those areas were skill shortages are expected. Therefore, the monitoring and supervision of EaP integration will be consequential in order to understand how much of the current brain waste is driven by poor assessment of foreign qualifications, and to unleash the potential of migration for the German economy