Entwicklung von Strategien zur Ausdehnung des Ökologischen Landbaus in Luxemburg

To develop strategies for the increase of organic production in Luxemburg, NGOs have initiated this empirical study. In total about 120 farmers will be interviewed to investigate motives and barriers for conversion and attitudes towards organic farming. Results are recommendations for political activities, information and advice. First results show surprising similarities with a study in Lower Saxony in 2003: Motives and barriers for conversion seem to be relatively independent of structural conditions and the development of the organic market. The differences are more obvious according to farmers interest, attitudes and knowledge about organic farming

That’s Not Who I Am! Investigating the Role of Uniqueness and Belongingness for Designing Successful Personalized Recommendations

Although many firms rely on personalization to enhance the user experience of their digital service, their efforts might backfire if users feel misunderstood by the personalized offerings. So far, the psychological processes underlying the phenomenon of feeling misunderstood by personalization systems and potential means to alleviate this perception remain largely uninvestigated. Building on the psychological concepts of uniqueness and belongingness, we propose a framework to investigate how transparency impacts users’ feeling of being misunderstood by personalization systems. To test our research model, we conduct an online experiment using Spotify’s “Discover Weekly” playlist. The results show that considering not only users’ uniqueness but especially their belongingness is decisive to avoid misunderstanding. Further, we find that transparent explanations of the system’s inner workings elicit a feeling of control among users, which fosters the perception that both users’ uniqueness and belongingness are considered, resulting in less misunderstanding and continued usage

Inventing Less, Reusing More and Adding Intelligence to Business Process Modeling

Recently, a variety of workflow patterns has been proposed focusing on specific aspects like control flow, data flow, and resource assignments. Though these patterns are relevant for implementing Business Process Modeling (BPM) tools and for evaluating the expressiveness of BPM languages, they do not contribute to reduce redundant specifications of recurrent business functions when modeling business processes. Furthermore, contemporary BPM tools do not support process designers in defining, querying, and reusing activity patterns as building blocks for process modeling. Related to these problems this paper proposes a set of activity patterns, evidences their practical relevance, and introduces a BPM tool for the modeling of business processes based on the reuse of these activity patterns. Altogether our approach fosters reuse of business functions specifications and helps to improve the quality and comparability of business process models

Intracardiac thrombus formation after the Fontan operation

AbstractObjectives: Intracardiac thrombus formation is suspected to be a specific sequela after the Fontan operation and is difficult to determine by means of routine transthoracic echocardiography. The aim of our study was to evaluate the occurrence of intracardiac thrombi in the different types of Fontan modifications and to identify predisposing risk factors. Methods: We evaluated 52 patients who had undergone a Fontan-type operation and were free of symptoms regarding thrombosis as determined by transesophageal echocardiography. Results: In 17 (33%) patients thrombus formation could be found without clinical evidence of thromboembolic complications. Neither underlying morphologic disease nor age at operation, type of Fontan operation, sex, follow-up interval, arrhythmias, or laboratory or hemodynamic findings could be identified as predisposing risk factors. Conclusion: In patients having had a Fontan operation with inadequate or without anticoagulation medication, we would recommend routine transesophageal echocardiography to exclude eventual thrombi. Because of the high incidence of thrombi, we suggest oral anticoagulation therapy in all patients. (J Thorac Cardiovasc Surg 2000;119:745-52

Sensory cortex lesion triggers compensatory neuronal plasticity

Background Lesions to the human brain often cause dramatic impairments in the life of patients because of the very limited capacity of the mammalian nervous system to regenerate. On the other hand, neuronal tissue has a high capacity to reorganize itself so that loss of function due to brain damage may be compensated through neuroplastic reorganization of undamaged tissue in brain regions adjacent or contralateral to the lesion site. In this study we investigated the effect of serial lesions of the auditory cortices (AC) in both hemispheres of Mongolian gerbils on discrimination performance for fast amplitude modulated tones (AM). Healthy animals were trained to discriminate two fast AM, an ability that has previously been shown to critically depend on cortical processing. Their ability to maintain significant discrimination performance was retested after unilateral AC lesion, and again after lesion of the contralateral AC, with 15 days of continuing training in between the two lesions. Results After bilateral cortical ablation of both AC and 45 days of training the animals show no change in pure tone detection threshold as measured with modulation of the acoustic startle reflex which has been shown to rely on subcortical structures. In contrast to simultaneous bilateral ablation of AC that results in complete loss of AM discrimination ability in this paradigm we found compensatory plasticity that seems to be triggered by unilateral cortical ablation with subsequent training and that is able to almost fully compensate for the lost cortical functions. Conclusions Our results demonstrate that AM discrimination ability that normally depends on AC may be transferred to other brain regions when the brain has time to activate compensatory plasticity between the lesions of the two AC hemispheres. For this process to take place obviously one intact AC hemisphere is needed. This finding may open perspectives for new therapeutic strategies that may alleviate the impairments after multiple ischemic strokes

Left ventricular systolic series elastic properties in aortic stenosis before and after valve replacement

In seven patients with aortic valve disease the time course of an auxotonic beat was compared with that of an isovolumetric beat produced by aortic cross clamping during open heart surgery. The rate of systolic stress rise (dS/dt; g·cm−2) of the isovolumetric beat at peak meridional wall stress (Sp; g·cm−2) of the auxotonic beat was determined by tipmanometry and simultaneous sonomicrometry and was found to be 87% of maximum dS/dt. In the second part of the study the stiffness index (k) was calculated in patients undergoing cardiac catheterisation according to: k = 0.87·(max·dS/dt)/Sp·Vcf, where Vcf = normalised midwall circumferential fibre shortening velocity (circ·s−1). In 22 patients, 10 controls and 12 patients with aortic stenosis before (pre) and after (post) valve replacement the systolic stiffness index k (circ−1) was determined using tipmanometry and frame by frame angiocardiography. Muscle fibre diameter and interstitial fibrosis were assessed from left ventricular endomyocardial biopsies. The systolic stiffness index k was 15 circ−1 in controls, 14 in preoperative patients with aortic stenosis and 12 (p<0.01 v controls) in postoperative patients. There was a significant correlation between k and muscle fibre diameter (r = 0.55; p<0.01) but not between k and interstitial fibrosis or ejection fraction. We conclude that systolic stiffness index k is normal despite marked left ventricular hypertrophy in preoperative patients with aortic stenosis. Following successful valve replacement systolic stiffness index decreased and was significantly lower than in controls. Series elasticity appears to be determined by structures related to the muscle cell rather than to interstitial fibrosi

Vortex structure in chiral p-wave superconductors

We investigate the vortex structure in chiral p-wave superconductors by the Bogoliubov-de Gennes theory on a tight-binding model. We calculate the spatial structure of the pair potential and electronic state around a vortex, including the anisotropy of the Fermi surface and superconducting gap structure. The differences of the vortex structure between $\sin p_x + {\rm i} \sin p_y$-wave and $\sin p_x - {\rm i} \sin p_y$-wave superconductors are clarified in the vortex lattice state. We also discuss the winding $\mp 3$ case of the $\sin{(p_x+p_y)} \pm {\rm i} \sin{(-p_x+p_y)}$-wave superconductivity.Comment: 10 pages, 8 figure

Fusion pore expansion is a slow, discontinuous, and Ca2+-dependent process regulating secretion from alveolar type II cells

In alveolar type II cells, the release of surfactant is considerably delayed after the formation of exocytotic fusion pores, suggesting that content dispersal may be limited by fusion pore diameter and subject to regulation at a postfusion level. To address this issue, we used confocal FRAP and N-(3-triethylammoniumpropyl)-4-(4-[dibutylamino]styryl) pyridinium dibromide (FM 1-43), a dye yielding intense localized fluorescence of surfactant when entering the vesicle lumen through the fusion pore (Haller, T., J. Ortmayr, F. Friedrich, H. Volkl, and P. Dietl. 1998. Proc. Natl. Acad. Sci. USA. 95:1579–1584). Thus, we have been able to monitor the dynamics of individual fusion pores up to hours in intact cells, and to calculate pore diameters using a diffusion model derived from Fick's law. After formation, fusion pores were arrested in a state impeding the release of vesicle contents, and expanded at irregular times thereafter. The expansion rate of initial pores and the probability of late expansions were increased by elevation of the cytoplasmic Ca2+ concentration. Consistently, content release correlated with the occurrence of Ca2+ oscillations in ATP-treated cells, and expanded fusion pores were detectable by EM. This study supports a new concept in exocytosis, implicating fusion pores in the regulation of content release for extended periods after initial formation

Molecular Aspects of Secretory Granule Exocytosis by Neurons and Endocrine Cells

Neuronal communication and endocrine signaling are fundamental for integrating the function of tissues and cells in the body. Hormones released by endocrine cells are transported to the target cells through the circulation. By contrast, transmitter release from neurons occurs at specialized intercellular junctions, the synapses. Nevertheless, the mechanisms by which signal molecules are synthesized, stored, and eventually secreted by neurons and endocrine cells are very similar. Neurons and endocrine cells have in common two different types of secretory organelles, indicating the presence of two distinct secretory pathways. The synaptic vesicles of neurons contain excitatory or inhibitory neurotransmitters, whereas the secretory granules (also referred to as dense core vesicles, because of their electron dense content) are filled with neuropeptides and amines. In endocrine cells, peptide hormones and amines predominate in secretory granules. The function and content of vesicles, which share antigens with synaptic vesicles, are unknown for most endocrine cells. However, in B cells of the pancreatic islet, these vesicles contain GABA, which may be involved in intrainsular signaling.' Exocytosis of both synaptic vesicles and secretory granules is controlled by cytoplasmic calcium. However, the precise mechanisms of the subsequent steps, such as docking of vesicles and fusion of their membranes with the plasma membrane, are still incompletely understood. This contribution summarizes recent observations that elucidate components in neurons and endocrine cells involved in exocytosis. Emphasis is put on the intracellular aspects of the release of secretory granules that recently have been analyzed in detail