Detection and measurement of the fast-fluctuating Gaussian random process dispersion abrupt change

We introduce the technically simple approach to the determination of the abrupt change of the unknown dispersion of the high-frequency fast-fluctuating Gaussian random process against white noise with an unknown spectral density. For this purpose, we determine new approximations of the decision statistics for various hypotheses, we carry out their maximization on unknown parameters, and we develop the block diagrams for the corresponding detector and measurer in the form of the comparatively simple single-channel units. For the analytical analysis of the performance of the synthesized algorithms, the asymptotically exact expressions for their characteristics, specifically - type I and type II error probabilities (when an abrupt change point is detected) and conditional biases and variances of the estimates (when measuring the parameters of the analyzed random process), are obtained by means of local Markov approximation method. We also illustrate a new procedure for determining the distribution law and the central moments of the estimate of the discontinuous parameter (abrupt change point), with an allowance of anomalous effects. The experimental testing of the presented theoretical results is implemented by the methods of statistical computer simulation

Why resilient workers perform better : the roles of job satisfaction and work engagement

Previous studies have confirmed correlations between resilience and job performance, but surprisingly little is known about the nature of this relationship. This study sheds light on the roles of two important positive dimensions of work-related well-being: job satisfaction and work engagement. Data were collected from 360 Czech workers in helping professions using an online survey. Levels of resilience and perceived job performance were indeed positively associated. Using structural equation modeling, the best-fitting model showed partial mediation by work engagement; conversely, job satisfaction was not found to be a mediator of this relationship. Additionally, the finding that job performance is related more strongly to work engagement than to job satisfaction contributes to the debate about the concurrent validity of job attitudes

HLA-DR+ leukocytes acquire CD1 antigens in embryonic and fetal human skin and contain functional antigen-presenting cells

Adequate numbers and functional maturity are needed for leukocytes to exhibit a protective role in host defense. During intrauterine life, the skin immune system has to acquire these prerequisites to protect the newborn from infection in the hostile external environment after birth. We investigated the quantitative, phenotypic, and functional development of skin leukocytes and analyzed the factors controlling their proliferation and trafficking during skin development. We show that CD45+ leukocytes are scattered in embryonic human skin and that their numbers continuously increase as the developing skin generates an environment that promotes proliferation of skin resident leukocytes as well as the influx of leukocytes from the circulation. We also found that CD45+HLA-DRhighCD1c+ dendritic cells (DCs) are already present in the epidermis and dermis at 9 wk estimated gestational age (EGA) and that transforming growth factor β1 production precedes Langerin and CD1a expression on CD45+CD1c+ Langerhans cell (LC) precursors. Functionally, embryonic antigen-presenting cells (APCs) are able to phagocytose antigen, to up-regulate costimulatory molecules upon culture, and to efficiently stimulate T cells in a mixed lymphocyte reaction. Collectively, our data provide insight into skin DC biology and the mechanisms through which skin DCs presumably populate the skin during development

IgM Promotes the Clearance of Small Particles and Apoptotic Microparticles by Macrophages

Background: Antibodies are often involved in enhancing particle clearance by macrophages. Although the mechanisms of antibody-dependent phagocytosis have been studied for IgG in greater detail, very little is known about IgM-mediated clearance. It has been generally considered that IgM does not support phagocytosis. Recent studies indicate that natural IgM is important to clear microbes and other bioparticles, and that shape is critical to particle uptake by macrophages; however, the relevance of IgM and particle size in their clearance remains unclear. Here we show that IgM has a sizedependent effect on clearance. Methodology/Principal Findings: We used antibody-opsonized sheep red blood cells, different size beads and apoptotic cells to determine the effect of human and mouse IgM on phagocytosis by mouse alveolar macrophages. Our microscopy (light, epifluorescence, confocal) and flow cytometry data show that IgM greatly enhances the clearance of small particles (about 1–2 micron) by these macrophages. There is an inverse relationship between IgM-mediated clearance by macrophages and the particle size; however, macrophages bind and internalize many different size particles coated with IgG. We also show that IgM avidly binds to small size late apoptotic cells or bodies (2–5 micron) and apoptotic microparticles (,2 mm) released from dying cells. IgM also promotes the binding and uptake of microparticle-coated beads. Conclusions/Significance: Therefore, while the shape of the particles is important for non-opsonized particle uptake, th

Subjective Video Quality Assessment of H.265 Compression Standard for Full HD Resolution

Recently increasing interest in multimedia services leads to requirements for quality assessment, especially in the video domain. There are many factors that influence the video quality. Compression technology and transmission link imperfection can be considered as the main ones. This paper deals with the assessment of the impact of H.265/HEVC compression standard on the video quality using subjective metrics. The evaluation is done for two types of sequences with Full HD resolution depending on content. The paper is divided as follows. In the first part of the article, a short characteristic of the H.265/HEVC compression standard is written. In the second part, the subjective video quality methods used in our experiments are described. The last part of this article deals with the measurements and experimental results. They showed that quality of sequences coded between 5 and 7 Mbps is for observers sufficient, so there is no need for providers to use higher bitrates in streaming than this threshold. These results are part of a new model that is still being created and will be used for predicting the video quality in networks based on IP

On-board Unit and its Possibilities of Communications on Safety and Security Principles

The technical solution of on-board unit (OBU) for vehicles used for dangerous good transport and design of vehicle sensor network (based on CAN bus) for dangerous good monitoring will be discussed. In presentation the conception of GSM/GPRS networking subsystem for real time data transmission into monitoring centre will be described. Next themes of discussion will be focused on the possibilities of solution of safety-related communication channel for safety sensor network in accordance with standard for functional safety of Electrical / Electronic / Programmable Electronic (E/E/PE) systems IEC 61508, recommended methods of risk analysis and possibilities of their modelling and proposal of secure communication channel over GSM/GPRS for secure data transmission into control centre on the base of IPsec protocol

Correction: Measuring psychological capital: Revision of the Compound Psychological Capital Scale (CPC-12).

[This corrects the article DOI: 10.1371/journal.pone.0247114.]

Relationship between Self-Efficacy, Transformational Leadership and Leader Effectiveness

Abstract-The aim of this research is to empirically investigate the relationship between a leader's self-efficacy, transformational leadership and leader effectiveness. On the basis of the literature and current leadership research review, the theoretical model, in which transformational leadership mediates the relationship between a leader's selfefficacy and effectiveness, is proposed. The research was conducted within a three-month-long management simulation game at two Czech universities. A total of 32 leaders participated together with 604 subordinates. The criteria of leader effectiveness included leadership emergence and perceived leader effectiveness, both assessed by the leaders' subordinates, and objectively measured by group performance. For the assessment of the transformational leadership approach of leaders, we administered a questionnaire based on the transformational leadership theory to their subordinates. The self-efficacy of leaders was measured by a self-report questionnaire filled by leaders. The relationship of self-efficacy to transformational leadership was not supported, as well as the association between leader's self-efficacy and criteria of leader effectiveness. Therefore, the mediation model with transformational leadership in the role of the mediator was not accepted

Causality of the Satisfaction–Performance Relationship: A Task Experiment

Despite the common belief among practitioners that a happy worker is a productive worker, researchers have been struggling to understand the causality between satisfaction and performance for decades. This study attempts to bring clarity to current understanding through an experiment with repeated measures of satisfaction and performance. A total of 143 participants repeatedly performed a task based on the Stroop test, with their objective performance and task satisfaction measured each time. Two different types of feedback (high/low performance) were randomly assigned to participants in order to manipulate perceived performance. The data were analyzed using a path analysis. The results support the hypothesized influence of task satisfaction on task performance and of perceived task performance on task satisfaction