54 resultados para distributed control and estimation
Resumo:
The performance of tasks that are perceived as unnecessary or unreasonable, illegitimate tasks, represents a new stressor concept that refers to assignments that violate the norms associated with the role requirements of professional work. Research has shown that illegitimate tasks are associated with stress and counterproductive work behaviour. The purpose of this study was to provide insight into the contribution of characteristics of the organization on the prevalence of illegitimate tasks in the work of frontline and middle managers. Using the Bern Illegitimate Task Scale (BITS) in a sample of 440 local government operations managers in 28 different organizations in Sweden, this study supports the theoretical assumptions that illegitimate tasks are positively related to stress and negatively related to satisfaction with work performance. Results further show that 10% of the variance in illegitimate tasks can be attributed to the organization where the managers work. Multilevel referential analysis showed that the more the organization was characterized by competition for resources between units, unfair and arbitrary resource allocation and obscure decisional structure, the more illegitimate tasks managers reported. These results should be valuable for strategic-level management since they indicate that illegitimate tasks can be counteracted by means of the organization of work.
Resumo:
Objectives: Athletes differ at staying focused on performance and avoiding distraction. Drawing on the strength model of self-control we investigated whether athletes do not only differ inter-individually in their disposition of staying focused and avoiding distraction but also intra-individually in their situational availability of focused attention. Design/method: In the present experiment we hypothesized that basketball players (N = 40) who have sufficient self-control resources will perform relatively better on a computer based decision making task under distraction conditions compared to a group who's self-control resources have been depleted in a prior task requiring self-control. Results: The results are in line with the strength model of self-control by demonstrating that an athlete's capability to focus attention relies on the situational availability of self-control strength. Conclusions: The current results indicate that having sufficient self-control strength in interference rich sport settings is likely to be beneficial for decision making.
Resumo:
Es wurde kürzlich gezeigt, dass die Stärke des Zusammenhangs zwischen Angst und Leistung von der momentan vorhandenen Selbstkontrollkraft abhängt. Wir untersuchten an einer Stichprobe aus Wirtschaftsschülern (N = 136), ob dieser Befund auf den Abruf von Wissen generalisierbar ist. Die Leistungsängstlichkeit der Teilnehmenden wurde erfasst und deren Selbstkontrollkraft experimentell manipuliert, woraufhin sie einen standardisierten Wortschatztest bearbeiteten. Während das Wissen nicht von der Leistungsängstlichkeit oder der Selbstkontrollkraft abhing, sagte die Interaktion aus beiden Variablen das gezeigte Wissen vorher. Übereinstimmend mit früheren Studien fiel die Leistung von Schülern mit niedriger Selbstkontrollkraft umso geringer aus, je leistungsängstlicher sie waren. Bei Schülern mit hoher Selbstkontrollkraft hingen die Leistungsängstlichkeit und die Wortschatzleistung hingegen nicht zusammen. Wir interpretieren dieses Muster dergestalt, dass Leistungsängstlichkeit den Wissensabruf nur dann behindert, wenn Selbstkontrolle nicht zur Kompensierung angstbezogener Aufmerksamkeitsdefizite herangezogen werden kann. Die Befunde implizieren, dass gründliche Vorbereitung keine guten Testnoten garantiert.
Resumo:
With more experience in the labor market, some job characteristics increase, some decrease. For example, among young employees who just entered the labor market, job control may initially be low but increase with more routine and experience. Job control is a job resource that is valued in itself and is positively associated with job satisfaction; but job control also helps dealing with stressors at work. There is little research on correlated changes, but the existing evidence suggests a joint development over time. However, even less is known about the relevance of such changes for employees. Usually, research tends to use mean levels to predict mean levels in outcomes but development in job control and stressors may be as relevant for job satisfaction as having a certain level in those job characteristics. Job satisfaction typically is regarded as a positive attitude towards one’s work. What has received less attention is that some employees may lower their expectations if their job situation does not reflect their needs, resulting in a resigned attitude towards one’s job. The present study investigates the development of job control and task-related stressors over ten years and tests the predictive value of changes in job control and task-related stressors for resigned attitude towards one’s job. We used data from a Swiss panel study (N=356) ranging over ten years. Job control, task-related stressors (an index consisting of time pressure, concentration demands, performance constraints, interruptions, and uncertainty about tasks), and resigned attitude towards one’s job were assessed in 1998, 1999, 2001, and 2008. Latent growth modeling revealed that growth rates of job control and task-related stressors were not correlated with one another. We predicted resigned attitude towards one’s job in 2008 a) by initial levels, and b) by changes in job control and stressors, controlling for resigned attitude in 1998. There was some prediction by initial levels (job control: β = -.15, p < .05; task-related stressors: β = .12, p = .06). However, as expected, changes in control and stressors predicted resigned attitude much better, with β = -.37, p < .001, for changes in job control, and β = .31, p < .001, for changes in task-related stressors. Our data confirm the importance of having low levels of task-related stressors and higher levels of job control for job attitudes. However, development in these job characteristics seems even more important than initial levels.
Resumo:
OBJECTIVE Vitamin D (D₃) status is reported to correlate negatively with insulin production and insulin sensitivity in patients with type 2 diabetes mellitus (T2DM). However, few placebo-controlled intervention data are available. We aimed to assess the effect of large doses of parenteral D3 on glycosylated haemoglobin (HbA(₁c)) and estimates of insulin action (homeostasis model assessment insulin resistance: HOMA-IR) in patients with stable T2DM. MATERIALS AND METHODS We performed a prospective, randomised, double-blind, placebo-controlled pilot study at a single university care setting in Switzerland. Fifty-five patients of both genders with T2DM of more than 10 years were enrolled and randomised to either 300,000 IU D₃ or placebo, intramuscularly. The primary endpoint was the intergroup difference in HbA(₁c) levels. Secondary endpoints were: changes in insulin sensitivity, albuminuria, calcium/phosphate metabolism, activity of the renin-aldosterone axis and changes in 24-hour ambulatory blood pressure values. RESULTS After 6 months of D₃ supply, there was a significant intergroup difference in the change in HbA(₁c) levels (relative change [mean ± standard deviation] +2.9% ± 1.5% in the D₃ group vs +6.9% ± 2.1% the in placebo group, p = 0.041) as HOMA-IR decreased by 12.8% ± 5.6% in the D₃ group and increased by 10% ± 5.4% in the placebo group (intergroup difference, p = 0.032). Twenty-four-hour urinary albumin excretion decreased in the D₃ group from 200 ± 41 to 126 ± 39, p = 0.021). There was no significant intergroup difference for the other secondary endpoints. CONCLUSIONS D₃ improved insulin sensitivity (based on HOMA-IR) and affected the course of HbA(₁c) positively compared with placebo in patients with T2DM.
Resumo:
This paper proposes a new estimator for the fixed effects ordered logit model. In contrast to existing methods, the new procedure allows estimating the thresholds. The empirical relevance and simplicity of implementation is illustrated in an application on the effect of unemployment on life satisfaction.
Resumo:
Sample preparation procedures for AMS measurements of 129I and 127I in environmental materials and some methodological aspects of quality assurance are discussed. Measurements from analyses of some pre-nuclear soil and thyroid gland samples and of a systematic investigation of natural waters in Lower Saxony, Germany, are described. Although the up-to-now lowest 129I/127I ratios in soils and thyroid glands were observed, they are still suspect to contamination since they are significantly higher than the pre-nuclear equilibrium ratio in the marine hydrosphere. A survey on all available 129I/127I isotopic ratios in precipitation shows a dramatic increase until the middle of the 1980s and a stabilization since 1987 at high isotopic ratios of about (3.6–8.3)×10−7. In surface waters, ratios of (57–380)×10−10 are measured while shallow ground waters show with ratios of (1.3–200)×10−10 significantly lower values with a much larger spread. The data for 129I in soils and in precipitation are used to estimate pre-nuclear and modern 129I deposition densities.
Resumo:
How can governance of civil society organizations be conceptualized more adequately by accounting for the dual and simultaneous requirements of controlling and coaching in board behavior? Empirically, we seem to agree that effective governance of a civil society organization is crucial to its sustained viability. Conceptually, however, we observe a lack of consensus on how to best conceptualize CSO governance. By critically juxtaposing two major theoretical lenses to conceptualize governance, namely agency and stewardship theory, we identify a number of challenges conceptualizing board-management relations that deserve our attention. While agency theory privileges controlling behavior, stewardship theory emphasizes the coaching behavior of boards. The purpose of this paper is to offer a concept of governance that is informed by a paradox perspective advancing a subtler, more adequate conceptualization of board governance that accounts for the often conflicting demands on CSO governance. Drawing on a longitudinal interpretive case study, we exemplify our propositions empirically. The paper concludes with discussing the implications of our argument for CSO governance research and practice.
Resumo:
We investigated the effects of different dietary vitamin D regimen on selected blood parameters in laying hens. Supplementation with vitamin D-3 only was compared with a combination of vitamin D-3 and its metabolite 25-hydroxy-cholecalciferol (25(OH)D-3). Blood concentrations of total calcium, phosphate and 25 (OH)D-3 were determined. Four thousand one-day-old LSL chicks were split in two treatment groups and distributed to eight pens. The control group was given a commercial animal diet containing 2800 IU synthetic vitamin D-3 in the starter feed and 2000 IU synthetic vitamin D-3 in the pullet feed. The experimental group was fed the same commercial diet in which half the synthetic vitamin D-3 content had been substituted with 25(OH)D-3 (Hy center dot D (R)). At 18 weeks of age, pullets were transferred to the layer house. At the ages of 11, 18 and 34 weeks, between 120 and 160 blood samples were collected from both the control and the experimental groups, respectively. The experimental group had higher levels of 25 (OH)D-3 than the control group at all three ages. Serum calcium levels did not differ between the treatment groups at any age. With the onset of laying, calcium levels rose significantly. Whereas blood serum concentration at 18 weeks was 3 mmol/L in both treatment groups, it increased to 8.32 mmol/L in the control group and to 8.66 mmol/L in the experimental group at week 34. At weeks 11 and 34, phosphate was significantly lower in the experimental group. In conclusion, HyD (R) significantly affected serum phosphate and 25(OH)D-3 levels. No effects of (25(OH)D-3 supplementation on performance, shell quality and fractures of keelbones were found.
Resumo:
Uncovering factors possibly leading to insufficient metabolic control in Type 1 diabetes, both on the part of the patient or the treating physician, is of considerable relevance. The present long-term study investigated the relevance of patient-related vs education-related factors for the success in achieving acceptable glycaemic control. Adolescents or young adults with Type 1 diabetes mellitus (n= 26, mean age= 22+/-2 yr, diabetes duration= 11+/-5 yr) were followed during 36+/-5 months. All patients were treated by the same diabetologist. At the beginning of the study coping behaviour, quality of life and evaluation of emotional status were assessed. Changes in HbA1c were used as a parameter of glycaemic control. At follow-up there was a significant decrease in HbA1c of 0.4% (p<0.01). However, this was not in statistically significant correlation with age, gender, aspects of quality of life or coping behaviour. Therefore, glycaemic control and/or improvement of glycaemic control in adolescents or young adults with Type 1 diabetes mellitus seems to be primarily related to other factors, eg continuous education provided in a stable setting.
Resumo:
Bovine spongiform encephalopathy (BSE) rapid tests and routine BSE-testing laboratories underlie strict regulations for approval. Due to the lack of BSE-positive control samples, however, full assay validation at the level of individual test runs and continuous monitoring of test performance on-site is difficult. Most rapid tests use synthetic prion protein peptides, but it is not known to which extend they reflect the assay performance on field samples, and whether they are sufficient to indicate on-site assay quality problems. To address this question we compared the test scores of the provided kit peptide controls to those of standardized weak BSE-positive tissue samples in individual test runs as well as continuously over time by quality control charts in two widely used BSE rapid tests. Our results reveal only a weak correlation between the weak positive tissue control and the peptide control scores. We identified kit-lot related shifts in the assay performances that were not reflected by the peptide control scores. Vice versa, not all shifts indicated by the peptide control scores indeed reflected a shift in the assay performance. In conclusion these data highlight that the use of the kit peptide controls for continuous quality control purposes may result in unjustified rejection or acceptance of test runs. However, standardized weak positive tissue controls in combination with Shewhart-CUSUM control charts appear to be reliable in continuously monitoring assay performance on-site to identify undesired deviations.