Defektstrukturen auf dünnen isolierenden Filmen

[no abstract

Immunological and genetic aspects of resistance to Salmonella in broilers

__Abstract__ Salmonella can be a threat for both public health and economy. Salmonellosis is one of the most common food-borne diseases in human. The economical problems in the poultry industry are caused by treatment of the infection, and the infection might lead to high levels of mortality of the flock. Moreover, the infection might lead to decreased animal welfare. To prevent these infections, and their consequences in chicken, birds can be vaccinated or treated with antibiotics. However, the use of antibiotics and vaccines has been criticized because of the possible development of antibiotic resistant bacteria and the potential dangers of antibiotic and vaccine residues in animal-derived food products. A solution to those issues could be the enhancement of natural genetic resistance, by improving the reaction of the host to a pathogen. This can be accomplished e.g. when the immune response of poultry can be enhanced. Research described in this thesis, provides insight on the differences in immune responses between chickens and within chicken lines in relation to disease resistance. Results of in vitro and in vivo studies showed, that the innate immune response played an important role in chickens in relation to natural and disease resistance. Furthermore, several genes were identified that were associated with Salmonella resistance in chicken. Overall, this study confirmed that disease resistance to Salmonella is a polygenic trait, which makes it difficult to apply in breeding strategies. However, together with other strategies to control Salmonella that already exist, the genetic approach may provide additional means to reduce the transmission of the infection and control Salmonella

Ambulatory assessment of rumination and worry. Capturing perseverative cognitions in children\u27s daily life

Rumination and worry are common forms of perseverative cognition in children. Research has started to target perseverative cognitions in the everyday life of children, however, valid measurement instruments reliably capturing rumination and worry in children\u27s daily life are still missing. We conducted two ambulatory assessment studies validating short scales suitable for the measurement of rumination and worry in children\u27s daily life. Results of the first study (N = 110, 8-11 year-olds, 31 days, up to 4 daily measurements) supported a unidimensional structure of the rumination scale. Rumination was associated with negative affect (but not positive affect) on the within- and on the between-person level. On the between-person level, children who ruminated more showed poorer working memory performance. In the second study (N = 84, 8-10 year-olds, 21 days, up to 3 daily measurements), findings of Study 1 were largely replicated. Moreover, we established a unidimensional worry scale in Study 2 reliably capturing worry in children\u27s daily life. Importantly, Study 2 showed that worry and rumination share common variance but can be differentiated in children. On the within-person level, higher levels of worry were associated with higher levels of negative affect and lower levels of positive affect. On the between-person level, worry was associated with higher levels of negative affect and lower working memory performance. Altogether, findings of both studies demonstrated that the short scales had excellent psychometric properties suggesting that they are helpful tools for the assessment of rumination and worry in children\u27s daily life.person level, worry was associated with higher levels of negative affect and lower working memory performance. Altogether, findings of both studies demonstrated that the short scales had excellent psychometric properties suggesting that they are helpful tools for the assessment of rumination and worry in children\u27s daily life. (DIPF/Orig.

Reciprocal relations of subjective sleep quality and affective well-being in late childhood

High sleep quality has been associated with beneficial outcomes across the life span. Intensive longitudinal studies suggest that these beneficial effects can also be observed on a day-to-day level. However, the dynamic interplay between subjective sleep quality and affective well-being in children\u27s daily life has only rarely been investigated. The aims of the present work were (a) to replicate findings from a prior ambulatory assessment study in this area (Könen et al., 2016), (b) to explore the effect of subjective sleep quality on well-being throughout the day, and (c) to examine the reciprocal relation between subjective sleep quality and well-being in more detail. Data from two ambulatory assessment studies with children between 8 and 11 years (N = 108/84, with assessments over 28/21 consecutive days) consistently showed that positive affect was higher and negative affect was lower after nights with better sleep quality, and that the effects of subjective sleep quality were stronger on well-being assessed in the morning compared with later in the day. Results from dynamic structural equation models revealed reciprocal effects of subjective sleep quality and positive affect. Negative affect was not consistently related to worse subsequent sleep quality after controlling for positive affect and prior night\u27s sleep quality. Results suggest a close relation of sleep quality and positive affect, which strengthens the idea behind interventions targeting both, children\u27s sleep and well-being. Differences between children in the dynamic interplay between sleep and affect may be important predictors of long-term outcomes. (DIPF/Orig.

Daily fluctuations of negative affect are only weakly associated with tremor symptoms in functional and organic tremor patients

BACKGROUND: There is a long-standing research history on the presumed psychological origin of functional movement disorders. Most studies do not address the heterogeneity in functional movement disorders and do not distinguish between risk factors, causes and consequences. We studied the associations between negative affect and objective as well as subjective symptom levels in patients with functional and organic tremor. METHODS: Thirty-three patients with a functional (14) or organic tremor (19) completed a web-based diary on subjective symptom burden and negative affect, five times a day for 30 days (total number of observations = 4759). During the same period, the participants wore an accelerometer to objectively record tremor. Vector autoregressive modelling was used to determine the time-lagged and contemporaneous associations between negative affect and objective/subjective tremor symptoms, both on an individual and a group level. RESULTS: In contrast to previous literature, patients with a functional or organic tremor showed a weak contemporaneous association between negative affect and objective/subjective tremor symptoms (on average r = 0.038 and 0.174 respectively). Time-lagged associations between negative affect and objective/subjective tremor symptoms were mixed in effect and direction and only present in a subset of patients, with no differences between patients with functional or organic tremor. CONCLUSIONS: Negative affect is only weakly associated with objective/subjective tremor symptoms, both on the contemporaneous and time-lagged associations, and these associations were mainly similar between patients with functional or organic tremor. These results argue against a strong influence of daily stress on tremor symptoms in patients with a functional or organic tremor

Oxidative stress and senescence in social insects:A significant but inconsistent link?

The life-prolonging effects of antioxidants have long entered popular culture, but the scientific community still debates whether free radicals and the resulting oxidative stress negatively affect longevity. Social insects are intriguing models for analysing the relationship between oxidative stress and senescence because life histories differ vastly between long-lived reproductives and the genetically similar but short-lived workers. Here, we present the results of an experiment on the accumulation of oxidative damage to proteins, and a comparative analysis of the expression of 20 selected genes commonly involved in managing oxidative damage, across four species of social insects: a termite, two bees and an ant. Although the source of analysed tissue varied across the four species, our results suggest that oxidative stress is a significant factor in senescence and that its manifestation and antioxidant defenses differ among species, making it difficult to find general patterns. More detailed and controlled investigations on why responses to oxidative stress may differ across social species may lead to a better understanding of the relations between oxidative stress, antioxidants, social life history and senescence. This article is part of the theme issue 'Ageing and sociality: why, when and how does sociality change ageing patterns

Learning to communicate computationally with Flip: a bi-modal programming language for game creation

Teaching basic computational concepts and skills to school children is currently a curricular focus in many countries. Running parallel to this trend are advances in programming environments and teaching methods which aim to make computer science more accessible, and more motivating. In this paper, we describe the design and evaluation of Flip, a programming language that aims to help 11–15 year olds develop computational skills through creating their own 3D role-playing games. Flip has two main components: 1) a visual language (based on an interlocking blocks design common to many current visual languages), and 2) a dynamically updating natural language version of the script under creation. This programming-language/natural-language pairing is a unique feature of Flip, designed to allow learners to draw upon their familiarity with natural language to “decode the code”. Flip aims to support young people in developing an understanding of computational concepts as well as the skills to use and communicate these concepts effectively. This paper investigates the extent to which Flip can be used by young people to create working scripts, and examines improvements in their expression of computational rules and concepts after using the tool. We provide an overview of the design and implementation of Flip before describing an evaluation study carried out with 12–13 year olds in a naturalistic setting. Over the course of 8 weeks, the majority of students were able to use Flip to write small programs to bring about interactive behaviours in the games they created. Furthermore, there was a significant improvement in their computational communication after using Flip (as measured by a pre/post-test). An additional finding was that girls wrote more, and more complex, scripts than did boys, and there was a trend for girls to show greater learning gains relative to the boys

A Bayesian Approach to Causality Assessment 1: Foundations

1 online resource (PDF, 39 pages

A Bayesian Approach to Causality Assessment

1 online resource (PDF, 79 pages

Scientific evidence underlying the ACC/AHA clinical practice guidelines

Context The joint cardiovascular practice guidelines of the American College of Cardiology (ACC) and the American Heart Association (AHA) have become important documents for guiding cardiology practice and establishing benchmarks for quality of care. Objective To describe the evolution of recommendations in ACC/AHA cardiovascular guidelines and the distribution of recommendations across classes of recommendations and levels of evidence. Data Sources and Study Selection Data from all ACC/AHA practice guidelines issued from 1984 to September 2008 were abstracted by personnel in the ACC Science and Quality Division. Fifty-three guidelines on 22 topics, including a total of 7196 recommendations, were abstracted. Data Extraction The number of recommendations and the distribution of classes of recommendation (I, II, and III) and levels of evidence (A, B, and C) were determined. The subset of guidelines that were current as of September 2008 was evaluated to describe changes in recommendations between the first and current versions as well as patterns in levels of evidence used in the current versions. Results Among guidelines with at least 1 revision or update by September 2008, the number of recommendations increased from 1330 to 1973 (+48%) from the first to the current version, with the largest increase observed in use of class II recommendations. Considering the 16 current guidelines reporting levels of evidence, only 314 recommendations of 2711 total are classified as level of evidence A (median, 11%), whereas 1246 (median, 48%) are level of evidence C. Level of evidence significantly varies across categories of guidelines (disease, intervention, or diagnostic) and across individual guidelines. Recommendations with level of evidence A are mostly concentrated in class I, but only 245 of 1305 class I recommendations have level of evidence A (median, 19%)