Ökologische Geflügelhaltung - Status quo und Ausblick

Die ökologische Geflügelhaltung befindet sich in einer schwierigen Situation: Bei tendenziell fallenden Preisen steigen die Kosten. Futter und Junghennen verteuern sich aufgrund der künftigen Regelungen der EG-Verordnung für ökologische Tierhaltung. Der Markt für Eier aus alternativen Haltungssystemen stagniert seit 2001. Es bestehen allerdings Möglichkeiten, die Haltungsbedingungen zu verbessern und Kosten zu senken. Dies ergab eine Untersuchung an der Universität Kassel

Die Einstellung von zukünftigen Lehrpersonen zum Impfen vor und nach einer Informationsveranstaltung

Zusammenfassung: Hintergrund: Seit Jahren tobt eine heftige gesellschaftliche Debatte um die Nützlichkeit bzw. Schädlichkeit von Impfungen. Das Ergebnis ist eine zunehmende Impfmüdigkeit in der Bevölkerung, die in der Medizin mit Besorgnis gesehen wird. Ziel: Die vorliegende Arbeit untersucht, ob die Vermittlung von konzeptionellem biomedizinischem Wissen junge Erwachsene in die Lage versetzt, verbreitete Impfmythen als solche zu erkennen und zurückzuweisen. Das Projekt nutzte eine Gesundheitswoche an einer pädagogischen Hochschule. Die Einstellung der Studierenden zum Impfen wurde vor und nach einer gezielten Intervention mit Hilfe eines Fragebogens untersucht. Ergebnis: Die Resultate zeigen, dass sich die Stellungnahmen der Studierenden zu je 7 Aussagen eines Impfbefürworters und eines Impfgegners hoch signifikant verändern. Die Vermittlung von konzeptuellem, biomedizinischem Wissen kann also einen Einfluss auf die Gesundheitskompetenz von Adoleszenten und jugendlichen Erwachsenen haben. Auch in der Gesundheitsförderung und Prävention sollten daher wissensdidaktischen Fragen größere Aufmerksamkeit gewidmet werde

Verhaltensprobleme in alternativen Legehennenhaltungen

In alternativen Haltungssystemen für Legehennen stellen Federpicken und Kannibalismus große Probleme dar. Aus der Literatur und Praxis besteht der Hinweis, dass ungünstige Aufzuchtbedingungen Hauptrisikofaktoren für das Auftreten dieser Verhaltensstörungen während der Legeperiode darstellen könnten. Hypothesenkataloge mit möglichen Risikofaktoren für Federpicken und Kannibalismus wurden erstellt und durch Berater und Wissenschaftler bewertet

A Preliminary Note on Egg Production from Milk-Fed Mosquitoes

Author Institution: Department of Zoology and Entomology, The Ohio State University, Columbus 1

Factors Affecting European Farmers’Participation in Biodiversity Policies

This article reports the major findings from an interdisciplinary research project that synthesises key insights into farmers’ willingness and ability to co-operate with biodiversity policies. The results of the study are based on an assessment of about 160 publications and research reports from six EU member states and from international comparative research.We developed a conceptual framework to systematically review the existent literature relevant for our purposes. This framework provides a common structure for analysing farmers’ perspectives regarding the introduction into farming practices of measures relevant to biodiversity. The analysis is coupled and contrasted with a survey of experts. The results presented above suggest that it is important to view support for practices oriented towards biodiversity protection not in a static sense – as a situation determined by one or several influencing factors – but rather as a process marked by interaction. Financial compensation and incentives function as a necessary, though clearly not sufficient condition in this process

Black Hole Mass Estimates Based on CIV are Consistent with Those Based on the Balmer Lines

Using a sample of high-redshift lensed quasars from the CASTLES project with observed-frame ultraviolet or optical and near-infrared spectra, we have searched for possible biases between supermassive black hole (BH) mass estimates based on the CIV, Halpha and Hbeta broad emission lines. Our sample is based upon that of Greene, Peng & Ludwig, expanded with new near-IR spectroscopic observations, consistently analyzed high S/N optical spectra, and consistent continuum luminosity estimates at 5100A. We find that BH mass estimates based on the FWHM of CIV show a systematic offset with respect to those obtained from the line dispersion, sigma_l, of the same emission line, but not with those obtained from the FWHM of Halpha and Hbeta. The magnitude of the offset depends on the treatment of the HeII and FeII emission blended with CIV, but there is little scatter for any fixed measurement prescription. While we otherwise find no systematic offsets between CIV and Balmer line mass estimates, we do find that the residuals between them are strongly correlated with the ratio of the UV and optical continuum luminosities. Removing this dependency reduces the scatter between the UV- and optical-based BH mass estimates by a factor of approximately 2, from roughly 0.35 to 0.18 dex. The dispersion is smallest when comparing the CIV sigma_l mass estimate, after removing the offset from the FWHM estimates, and either Balmer line mass estimate. The correlation with the continuum slope is likely due to a combination of reddening, host contamination and object-dependent SED shapes. When we add additional heterogeneous measurements from the literature, the results are unchanged.Comment: Accepted for publication in The Astrophysical Journal. 37 text pages + 8 tables + 23 figures. Updated with comments by the referee and with a expanded discussion on literature data including new observation

Brains studying brains: look before you think in vision

Using our own brains to study our brains is extraordinary. For example, in vision this makes us naturally blind to our own blindness, since our impression of seeing our world clearly is consistent with our ignorance of what we do not see. Our brain employs its 'conscious' part to reason and make logical deductions using familiar rules and past experience. However, human vision employs many 'subconscious' brain parts that follow rules alien to our intuition. Our blindness to our unknown unknowns and our presumptive intuitions easily lead us astray in asking and formulating theoretical questions, as witnessed in many unexpected and counter-intuitive difficulties and failures encountered by generations of scientists. We should therefore pay a more than usual amount of attention and respect to experimental data when studying our brain. I show that this can be productive by reviewing two vision theories that have provided testable predictions and surprising insights

The Roles of Transmembrane Domain Helix-III during Rhodopsin Photoactivation

Background: Rhodopsin, the prototypic member of G protein-coupled receptors (GPCRs), undergoes isomerization of 11- cis-retinal to all-trans-retinal upon photoactivation. Although the basic mechanism by which rhodopsin is activated is well understood, the roles of whole transmembrane (TM) helix-III during rhodopsin photoactivation in detail are not completely clear. Principal Findings: We herein use single-cysteine mutagenesis technique to investigate conformational changes in TM helices of rhodopsin upon photoactivation. Specifically, we study changes in accessibility and reactivity of cysteine residues introduced into the TM helix-III of rhodopsin. Twenty-eight single-cysteine mutants of rhodopsin (P107C-R135C) were prepared after substitution of all natural cysteine residues (C140/C167/C185/C222/C264/C316) by alanine. The cysteine mutants were expressed in COS-1 cells and rhodopsin was purified after regeneration with 11-cis-retinal. Cysteine accessibility in these mutants was monitored by reaction with 4, 49-dithiodipyridine (4-PDS) in the dark and after illumination. Most of the mutants except for T108C, G109C, E113C, I133C, and R135C showed no reaction in the dark. Wide variation in reactivity was observed among cysteines at different positions in the sequence 108–135 after photoactivation. In particular, cysteines at position 115, 119, 121, 129, 131, 132, and 135, facing 11-cis-retinal, reacted with 4-PDS faster than neighboring amino acids. The different reaction rates of mutants with 4-PDS after photoactivation suggest that the amino acids in different positions in helix-III are exposed to aqueous environment to varying degrees. Significance: Accessibility data indicate that an aqueous/hydrophobic boundary in helix-III is near G109 and I133. The lack of reactivity in the dark and the accessibility of cysteine after photoactivation indicate an increase of water/4-PDS accessibility for certain cysteine-mutants at Helix-III during formation of Meta II. We conclude that photoactivation resulted in water-accessible at the chromophore-facing residues of Helix-III.National Institutes of Health (U.S.) (grant GM28289)National Eye Institute (Grant Grant EY11716)National Science Foundation (U.S.) (grant EIA-0225609

Physiology-based simulation of the retinal vasculature enables annotation-free segmentation of OCT angiographs

Optical coherence tomography angiography (OCTA) can non-invasively image the eye's circulatory system. In order to reliably characterize the retinal vasculature, there is a need to automatically extract quantitative metrics from these images. The calculation of such biomarkers requires a precise semantic segmentation of the blood vessels. However, deep-learning-based methods for segmentation mostly rely on supervised training with voxel-level annotations, which are costly to obtain. In this work, we present a pipeline to synthesize large amounts of realistic OCTA images with intrinsically matching ground truth labels; thereby obviating the need for manual annotation of training data. Our proposed method is based on two novel components: 1) a physiology-based simulation that models the various retinal vascular plexuses and 2) a suite of physics-based image augmentations that emulate the OCTA image acquisition process including typical artifacts. In extensive benchmarking experiments, we demonstrate the utility of our synthetic data by successfully training retinal vessel segmentation algorithms. Encouraged by our method's competitive quantitative and superior qualitative performance, we believe that it constitutes a versatile tool to advance the quantitative analysis of OCTA images