Lebensqualität von Brustkrebspatientinnen bei offener und verschlossener Reaktion auf ein Gesprächs- und Informationsangebot

Da sich die Voraussetzungen in der Nachsorge von Patientinnen mit Brustkrebs im letzten Jahrzehnt verändert haben, wird im Theorieteil der Arbeit auf das Konzept Lebensqualität, die Krankheit Brustkrebs selbst, die aktuellen Nachsorgebedingungen und auf Coping eingegangen. Im Anschluß erfolgt die Darstellung der Ergebnisse von 204 Patientinnen, die zwischen 1996 und 1998 an einem neu diagnostizierten Mammakarzinom erkrankt und operiert worden sind. Die Daten wurden bezüglich der Lebensqualität in der Nachsorgeperiode von einem Jahr ausgewertet. Als Meßinstrument wurde der Quality of Life Questionnaire der EORTC benutzt. Es zeigt sich, daß sich für alle Patientinnen die Lebensqualität im Verlauf von einem Jahr signifikant erhöht. Die Patientinnen, die eine offene Haltung bezüglich eines Informations- und Gesprächsangebots zeigen (n=43), haben zum Zeitpunkt der Klinikentlassung und nach 12 Monaten eine signifikant schlechtere globale Lebensqualität als die verschlossenen Patientinnen (n=12). Die bezüglich des Gesprächs- und Informationsangebots indifferenten Patientinnen (n=149) nehmen einen Mittelplatz ein. Als weiteres Ergebnis zeigt sich ein signifikanter Unterschied zwischen der Selbsteinschätzung der Lebensqualität durch die Patientinnen und der Fremdeinschätzung der Lebensqualität durch die Interviewführenden. Die Patientinnen schätzen ihre globale Lebensqualität signifikant schlechter ein (Mittelwert: 58), als dies in der Fremdeinschätzung durch die Interviewführenden der Fall ist (Mittelwert: 63,2).Die Ergebnisse könnten darauf hindeuten, daß die Offenheit der Patientinnen aus einer inneren Not heraus besteht, während die verschlossenen Patientinnen durch die größere Distanz zum Thema Brustkrebs von einer höheren Lebensqualität profitieren. Die in der Literatur referierten Ergebnisse bezüglich der Selbst- und Fremdeinschätzung der Lebensqualität finden in dieser Studie keine Bestätigung. Es wird deutlich, daß es in der Nachsorge unterschiedliche Reaktionen mit Auswirkung auf die Lebensqualität der Patientinnen gibt; eine Forschungsvertiefung wäre für die bessere Kenntnis der psychosozialen Situation der Patientinnen und nachfolgend für eine Verbesserung der Nachsorge im Sinne der aktuellen Leitlinien wünschenswert

A stochastic model for the evolution of the web allowing link deletion

Recently several authors have proposed stochastic evolutionary models for the growth of the web graph and other networks that give rise to power-law distributions. These models are based on the notion of preferential attachment leading to the ``rich get richer'' phenomenon. We present a generalisation of the basic model by allowing deletion of individual links and show that it also gives rise to a power-law distribution. We derive the mean-field equations for this stochastic model and show that by examining a snapshot of the distribution at the steady state of the model, we are able to tell whether any link deletion has taken place and estimate the link deletion probability. Our model enables us to gain some insight into the distribution of inlinks in the web graph, in particular it suggests a power-law exponent of approximately 2.15 rather than the widely published exponent of 2.1

Biotransformation of Chemicals at the Water–Sediment Interface─Toward a Robust Simulation Study Setup

Studying aquatic biotransformation of chemicals in laboratory experiments, i.e., OECD 308 and OECD 309 studies, is required by international regulatory frameworks to prevent the release of persistent chemicals into natural water bodies. Here, we aimed to address several previously described shortcomings of OECD 308/309 studies regarding their variable outcomes and questionable environmental relevance by broadly testing and characterizing a modified biotransformation test system in which an aerated water column covers a thin sediment layer. Compared to standard OECD 308/309 studies, the modified system showed little inter-replicate variability, improved observability of biotransformation, and consistency with first-order biotransformation kinetics for the majority of 43 test compounds, including pharmaceuticals, pesticides, and artificial sweeteners. To elucidate the factors underlying the decreased inter-replicate variability compared to OECD 309 outcomes, we used multidimensional flow cytometry data and a machine learning-based cell type assignment pipeline to study cell densities and cell type diversities in the sediment and water compartments. Our here presented data on cell type composition in both water and sediment allows, for the first time, to study the behavior of microbial test communities throughout different biotransformation simulation studies. We found that sediment-associated microbial communities were generally more stable throughout the experiments and exhibited higher cell type diversity than the water column-associated communities. Consistently, our data indicate that aquatic biotransformation of chemicals can be most robustly studied in test systems providing a sufficient amount of sediment-borne biomass. While these findings favor OECD 308-type systems over OECD 309-type systems to study biotransformation at the water–sediment interface, our results suggest that the former should be modified toward lower sediment–water ratios to improve observability and interpretability of biotransformation. KEYWORDS- biotransformation micropollutants chemical persistence water−sediment systems phenotypic microbial community composition cell type diversity OECD 308/309 studie

Quantum Weakly Nondeterministic Communication Complexity

We study the weakest model of quantum nondeterminism in which a classical proof has to be checked with probability one by a quantum protocol. We show the first separation between classical nondeterministic communication complexity and this model of quantum nondeterministic communication complexity for a total function. This separation is quadratic.Comment: 12 pages. v3: minor correction

A stochastic evolutionary model for capturing human dynamics

The recent interest in human dynamics has led researchers to investigate the stochastic processes that explain human behaviour in various contexts. Here we propose a generative model to capture the dynamics of survival analysis, traditionally employed in clinical trials and reliability analysis in engineering. We derive a general solution for the model in the form of a product, and then a continuous approximation to the solution via the renewal equation describing age-structured population dynamics. This enables us to model a wide range of survival distributions, according to the choice of the mortality distribution. We provide empirical evidence for the validity of the model from a longitudinal data set of popular search engine queries over 114 months, showing that the survival function of these queries is closely matched by the solution for our model with power-law mortality

Effects of pre-conditioning on behavior and physiology of horses during a standardised learning task

Rein tension is used to apply pressure to control both ridden and unridden horses. The pressure is delivered by equipment such as the bit, which may restrict voluntary movement and cause changes in behavior and physiology. Managing the effects of such pressure on arousal level and behavioral indicators will optimise horse learning outcomes. This study examined the effect of training horses to turn away from bit pressure on cardiac outcomes and behavior (including responsiveness) over the course of eight trials in a standardised learning task. The experimental procedure consisted of a resting phase, treatment/control phase, standardised learning trials requiring the horses (n = 68) to step backwards in response to bit pressure and a recovery phase. As expected, heart rate increased (P = 0.028) when the handler applied rein tension during the treatment phase. The amount of rein tension required to elicit a response during treatment was higher on the left than the right rein (P = 0.009). Total rein tension required for trials reduced (P \u3c 0.001) as they progressed, as did time taken (P \u3c 0.001) and steps taken (P \u3c 0.001). The incidence of head tossing decreased (P = 0.015) with the progression of the trials and was higher (P = 0.018) for the control horses than the treated horses. These results suggest that preparing the horses for the lesson and slightly raising their arousal levels, improved learning outcomes