799 research outputs found

    5.10 How do Regulatory Requirements and Assumptions Correlate to Practical Experience in Residue Studies with Nectar and Pollen?

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    Residues of pesticides detected in pollen and nectar (bee relevant matrices) represent a realistic research approach to estimate pollinator exposure. Therefore, a robust and reliable method to sample and measure these residues is part of risk assessment schemes in several parts of the world. EFSA guidance for pollinators was the first risk assessment to allow for the refinements of the expected residue values during exposure. EPA as well as IBAMA followed suite and proposed in vivo refinements for residue values. To achieve this goal nectar and pollen from plant species have to be collected in sufficient amounts to allow for residue analysis. Several methods are available for the collection of bee matrices. We list general methods developed to sample pollen and nectar, focus on some common issues encountered during the conduct of these studies and place the measurements derived from these studies into a risk assessment context. With all the information available now it would be a useful task to compare residue levels in matrices collected manually and with the help of pollinators to give advice for guidance document refinements and help to approve the design of studies in the future.Residues of pesticides detected in pollen and nectar (bee relevant matrices) represent a realistic research approach to estimate pollinator exposure. Therefore, a robust and reliable method to sample and measure these residues is part of risk assessment schemes in several parts of the world. EFSA guidance for pollinators was the first risk assessment to allow for the refinements of the expected residue values during exposure. EPA as well as IBAMA followed suite and proposed in vivo refinements for residue values. To achieve this goal nectar and pollen from plant species have to be collected in sufficient amounts to allow for residue analysis. Several methods are available for the collection of bee matrices. We list general methods developed to sample pollen and nectar, focus on some common issues encountered during the conduct of these studies and place the measurements derived from these studies into a risk assessment context. With all the information available now it would be a useful task to compare residue levels in matrices collected manually and with the help of pollinators to give advice for guidance document refinements and help to approve the design of studies in the future

    Improvement of the Effects Dispersion Model for Under Expanded Turbulent Jets

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    Recently, the dispersion model in EFFECTS was updated and extensively validated for light gas situations including jet releases and lifting plumes. In the present paper the modifications for gaseous turbulent jets will be discussed. This includes the full release velocity range from low subsonic to supersonic flow under highly under expanded conditions which are highly relevant for the high-pressure storage of hydrogen. In particular, a new model for the calculation of the expanded diameter in combination with an adapted implementation of the Chen and Rodi model was developed. The models were validated against a wide range of experimental classical and recent data sets including concentration and velocity data. This also includes a wide range of initial densities from lighter than air to heavy gas which will be discussed in this paper. The simulations show excellent agreement with experimental data resulting in less conservative predictions compared with the previous models

    Cyclic unparticle physics

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    We explore phenomenological consequences of coupling a non-conformal scale-invariant theory to the standard model. We point out that, under certain circumstances, non-conformal scale-invariant theories have oscillating correlation functions which can dramatically modify standard model processes. We dub this scenario cyclic unparticle physics, or simply cyclunparticle physics. We compute phase spaces and amplitudes associated with final state cyclunparticle and cyclunparticle exchange, respectively. We show detailed formulae in a simple example.Comment: 12 pages, 2 figure

    Determinants of the perceived administrative transaction costs caused by the uptake of an agri-environmental program

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    Farmers’ subjectively perceived that administrative transaction costs are of high importance for the uptake of agri-environmental programs with direct effects on the effectiveness and efficiency of these programs and the well-being of farmers. This paper empirically estimates private administrative transaction costs resulting from an uptake of the newly introduced grassland-based milk and meat program in Switzerland, based on farmers’ perceived administrative workload. Using ordered logit models, we analyze how the administrative tasks and farm and farmer characteristics influence the perceived administrative workload. We find that the time spent on monitoring or inspection tasks has no effect. In contrast, an outsourcing of program-related administrative tasks significantly reduces the perceived administrative workload. We also find that a better understanding of agricultural policy regulations significantly reduces the farmers’ perceived administrative workload. We recommend that public administration improve the communication of agricultural policy regulations, rather than investing in the simplification of administrative forms

    Distribution of corpora amylacea in the human midbrain: using synchrotron radiation phase-contrast microtomography, high-field magnetic resonance imaging, and histology

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    Corpora amylacea (CA) are polyglucosan aggregated granules that accumulate in the human body throughout aging. In the cerebrum, CA have been found in proximity to ventricular walls, pial surfaces, and blood vessels. However, studies showing their three-dimensional spatial distribution are sparse. In this study, volumetric images of four human brain stems were obtained with MRI and phase-contrast X-ray microtomography, followed up by Periodic acid Schiff stain for validation. CA appeared as hyperintense spheroid structures with diameters up to 30μm. An automatic pipeline was developed to segment the CA, and the spatial distribution of over 200,000 individual corpora amylacea could be investigated. A threefold—or higher—density of CA was detected in the dorsomedial column of the periaqueductal gray (860–4,200 CA count/mm3) than in the superior colliculus (150–340 CA count/mm3). We estimated that about 2% of the CA were located in the immediate vicinity of the vessels or in the peri-vascular space. While CA in the ependymal lining of the cerebral aqueduct was rare, the sub-pial tissue of the anterior and posterior midbrain contained several CA. In the sample with the highest CA density, quantitative maps obtained with MRI revealed high R2∗ values and a diamagnetic shift in a region which spatially coincided with the CA dense region

    Air cooling powered by façade integrated coloured opaque solar thermal panels

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    For building integration of solar-powered energy systems, aesthetic aspects play an importantrole. Covering a standard solar collector with a coloured glazing, opaque to the human eye but highly transparent to solar energy, permits a perfect architectural integration of solar thermal panels into glazed building façades. The thermal energy produced can be used for both solar heating and cooling, as well as for domestic hot water. The principle of the coloured appearance is based on interference in the thin-film coating on the reverse side of the cover glass. Different interference filters based on nano-composite materials deposited by the solgel method were presented at CISBAT 2007 [1]. Currently, we are developing new plasma-deposition processes, which are more suitable for industrial large-scale production. A new state-of-the-art ultra-high vacuum (UHV) system for magnetron sputtering deposition of novel nano-composite solar coatings has recently been designed, constructed, and installed at the Solar Energy and Building Physics Laboratory (LESO-PB). Up to five different magnetron sources can be used simultaneously, in reactive and non-reactive mode. The geometric configuration of the chamber has been optimised for best film homogeneity and allows the deposition on substrates up to 100 mm in diameter. The optical and electronic properties of thin films are closely interrelated and highly relevant for solar coatings. Photoelectron spectroscopy provides information on the coating structure, the deposited material and its chemical state inside the coating, as well as the nature of the interface between different layers. A system for ESCA analysis (Electron Spectroscopy for Chemical Analysis) has recently been installed and put into operation at LESO-PB. By ellipsometry and spectrophotometry, we can determine exactly the different optical properties of the coating, such as layer thickness, refractive index, or absorption coefficient. This provides best conditions for highly efficient research and development on new materials for further optimisation of the coloured interference filters.First results have been obtained with our new experimental infrastructure and will be presented in this contribution

    Conventional weight loss therapy in morbid obesity during COVID-19 pandemic: degree of burdens at baseline and treatment efficacy

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    IntroductionCOVID-19 affected global physical and psychological health. The purpose of this study was to explore the pandemics impact on health-related quality of life (HRQoL), mental health (anxiety, depression, and perceived stress) and eating behavior in people with severe obesity participating in a multimodal conservative behavioral weight loss (BWL) program conducted via videoconferencing. Additionally, the efficacy of the six-month BWL program in a virtual video-based setting during the pandemic was examined.Methods297 participants of a face-to-face multimodal behavioral weight loss program prior to the pandemic (PrePAN, May 2014–September 2019) and 146 participants of the in terms of content same intervention in a videoconference-based setting during the pandemic (PAN, July 2020–April 2022) were questioned and compared using standardized questionnaires for HRQoL, symptoms of depressive and anxiety disorders, perceived stress, and eating behavior at baseline and at the end of treatment.ResultsSymptoms for anxiety, depression and perceived stress were similar between PrePAN and PAN at baseline. In addition, PAN tended to show lower disinhibition of eating behavior and feelings of hunger than PrePAN. During the pandemic, the BWL intervention resulted in body weight loss (67%) or stabilization (16%) in most of the participants. It also contributed by improving physical HRQoL, lower worries, and improved eating behaviors compared to baseline.ConclusionDuring the COVID-19 pandemic, baseline mental health of people with morbid obesity was not worse than before the pandemic. Additionally, the BWL intervention in the virtual video-based setting stabilized and improved physical and mental health during the COVID-19 pandemic
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