Führungsverhalten beziehungsweise Führungsstile in Agrarunternehmen

The development of the relationship between employer and employee is an important aspect of management, i. e. management behaviour and management style play an important role with regard to the employee as a critical factor for success. Increasing average sizes of agricultural enterprises and numbers of employees and the missing hierarchical structures create the need for additional motivation opportunities. In the agricultural sector the quality performance of labour activities is difficult to control, therefore, it becomes even more important to discuss management behaviour and management styles. Management styles are mainly described theoretically in the literature but rarely for agricultural enterprises. An empirical study demonstrates that in practice agricultural entrepreneurs are aware of numerous management styles. Although various standard management styles are known to the managers, the successful manager quickly adapts his individual management style to the current situation.management behaviour, management styles, Farm Management, Labor and Human Capital,

Quantification of harms in cancer screening trials: literature review

Objectives To assess how often harm is quantified in randomised trials of cancer screening. Design Two authors independently extracted data on harms from randomised cancer screening trials. Binary outcomes were described as proportions and continuous outcomes with medians and interquartile ranges. Data sources For cancer screening previously assessed in a Cochrane review, we identified trials from their reference lists and updated the search in CENTRAL. For cancer screening not assessed in a Cochrane review, we searched CENTRAL, Medline, and Embase. Eligibility criteria for selecting studies Randomised trials that assessed the efficacy of cancer screening for reducing incidence of cancer, cancer specific mortality, and/or all cause mortality. Data extraction Two reviewers independently assessed articles for eligibility. Two reviewers, who were blinded to the identity of the study's authors, assessed whether absolute numbers or incidence rates of outcomes related to harm were provided separately for the screening and control groups. The outcomes were false positive findings, overdiagnosis, negative psychosocial consequences, somatic complications, invasive follow-up procedures, all cause mortality, and withdrawals because of adverse events. Results Out of 4590 articles assessed, 198 (57 trials, 10 screening technologies) matched the inclusion criteria. False positive findings were quantified in two of 57 trials (4\%, 95\% confidence interval 0\% to 12\%), overdiagnosis in four (7\%, 2\% to 18\%), negative psychosocial consequences in five (9\%, 3\% to 20\%), somatic complications in 11 (19\%, 10\% to 32\%), use of invasive follow-up procedures in 27 (47\%, 34\% to 61\%), all cause mortality in 34 (60\%, 46\% to 72\%), and withdrawals because of adverse effects in one trial (2\%, 0\% to 11\%). The median percentage of space in the results section that reported harms was 12\% (interquartile range 2-19\%). Conclusions Cancer screening trials seldom quantify the harms of screening. Of the 57 cancer screening trials examined, the most important harms of screening-overdiagnosis and false positive findings-were quantified in only 7\% and 4\%, respectively.publishersversionpublishe

Spatially Confined Redox Chemistry in Periodic Mesoporous Hydridosilica-Nanosilver Grown in Reducing Nanopores

Cataloged from PDF version of article.Periodic mesoporous hydridosilica, PMHS, is shown for the first time to function as both a host and a mild reducing agent toward noble metal ions. In this archetypical study, PMHS microspheres react with aqueous Ag(I) solutions to form Ag(0) nanopartides housed in different pore locations of the mesostructure. The dominant reductive nucleation and growth process involves groups located within the pore walls and yields molecular scale Ag(0) nanoclusters trapped and stabilized in the pore walls of the PMHS microspheres that emit orange-red photoluminescence. Lesser processes initiated with pore surface SiH groups produce some larger spherical and worm-shaped Ag(0) nanoparticles within the pore voids and on the outer surfaces of the PMHS microspheres. The intrinsic reducing power demonstrated in this work for the pore walls of PMHS speaks well for a new genre of chemistry that benefits from the mesoscopic confinement of Si-H groups

TRENDS AND DEVELOPMENT IN CHIRONOMID PALAEOECOLOGY: SUMMARY FROM THE

-

Short comment on chironomid assemblages and stratigraphy of high altitude lakes from Tibet

A recent chironomid record of three shallow, high altitude lakes in southern Tibet, as well as a short palaeolimnological history of one lake, are presented. The recent chironomid assemblages consisted of 13 taxa; one of the Orthocladiinae taxa recorded most likely represents a new species. In spite of the low head capsule concentration in the sediment core of Lake Karuugema, probably due to physical disturbance, redistribution and outwash of head capsules, there was a trend from assemblages composed of stenothermal/rheophilic taxa to eurythermal/limnophilic taxa. This shift in assemblage structure suggests that changes in monsoon precipitation and catchment hydrology may have influenced the habitat conditions of the chironomids

Bayesian mixed-effects inference on classification performance in hierarchical data sets

Classification algorithms are frequently used on data with a natural hierarchical structure. For instance, classifiers are often trained and tested on trial-wise measurements, separately for each subject within a group. One important question is how classification outcomes observed in individual subjects can be generalized to the population from which the group was sampled. To address this question, this paper introduces novel statistical models that are guided by three desiderata. First, all models explicitly respect the hierarchical nature of the data, that is, they are mixed-effects models that simultaneously account for within-subjects (fixed-effects) and across-subjects (random-effects) variance components. Second, maximum-likelihood estimation is replaced by full Bayesian inference in order to enable natural regularization of the estimation problem and to afford conclusions in terms of posterior probability statements. Third, inference on classification accuracy is complemented by inference on the balanced accuracy, which avoids inflated accuracy estimates for imbalanced data sets. We introduce hierarchical models that satisfy these criteria and demonstrate their advantages over conventional methods usingMCMC implementations for model inversion and model selection on both synthetic and empirical data. We envisage that our approach will improve the sensitivity and validity of statistical inference in future hierarchical classification studies. © 2012

Toxin inhibition in <i>C. crescentus</i> VapBC1 is mediated by a flexible pseudo-palindromic protein motif and modulated by DNA binding

Expression of bacterial type II toxin-antitoxin (TA) systems is regulated at the transcriptional level through direct binding of the antitoxin to pseudo-palindromic sequences on operator DNA. In this context, the toxin functions as a co-repressor by stimulating DNA binding through direct interaction with the antitoxin. Here, we determine crystal structures of the complete 90 kDa heterooctameric VapBC1 complex from Caulobacter crescentus CB15 both in isolation and bound to its cognate DNA operator sequence at 1.6 and 2.7 Å resolution, respectively. DNA binding is associated with a dramatic architectural rearrangement of conserved TA interactions in which C-terminal extended structures of the antitoxin VapB1 swap positions to interlock the complex in the DNA-bound state. We further show that a pseudo-palindromic protein sequence in the antitoxin is responsible for this interaction and required for binding and inactivation of the VapC1 toxin dimer. Sequence analysis of 4127 orthologous VapB sequences reveals that such palindromic protein sequences are widespread and unique to bacterial and archaeal VapB antitoxins suggesting a general principle governing regulation of VapBC TA systems. Finally, a structure of C-terminally truncated VapB1 bound to VapC1 reveals discrete states of the TA interaction that suggest a structural basis for toxin activation in vivo