1.22 Weight differences of honey bees after administration of sublethal doses of dimethoate

Background: The aim of this work was to assess honey bee body weight as a possible further parameter to detect effects in a 10 day chronic feeding study according to OECD 2451 following exposure to sublethal concentrations of a plant protection product (i.e. dimethoate). This investigation is based on the assumption that weight differences might be caused by chronic feeding of dimethoate. Two set of tests in two different laboratories (Lab 1 and Lab 2) were conducted in order to investigate possible weight changes of complete adult honey bees and/or parts of their body (honey stomach and intestine) following treatment of dimethoate. Bees were weighed before and after chronic feeding of sub-lethal concentrations of dimethoate. Results: Differences in the number of bees which lost weight following treatment of sublethal concentrations of dimethoate was found in Lab 1, but could not confirmed in Lab 2. The difference in weight between the control group and the dimethoate treatment could only be detected as a statistical significant difference in one lab at the highest concentration (0.4 mg/kg). Assessment of weight changes of parts of the bee body (honey stomach and intestine) shows a very high variation (CV) which makes interpretation of the data of the total body weight questionable. Conclusion: The results of the two laboratories were contradictory and no conclusive assessment can be done following the two sets of experiments. Assessment of bee body weight within a 10-day chronic feeding study is considered questionable for the detection of sublethal effects. Further work with other active ingredients is needed to clarify if body weight change of honey bees can be used as a parameter for sublethal effects.Background: The aim of this work was to assess honey bee body weight as a possible further parameter to detect effects in a 10 day chronic feeding study according to OECD 2451 following exposure to sublethal concentrations of a plant protection product (i.e. dimethoate). This investigation is based on the assumption that weight differences might be caused by chronic feeding of dimethoate. Two set of tests in two different laboratories (Lab 1 and Lab 2) were conducted in order to investigate possible weight changes of complete adult honey bees and/or parts of their body (honey stomach and intestine) following treatment of dimethoate. Bees were weighed before and after chronic feeding of sub-lethal concentrations of dimethoate. Results: Differences in the number of bees which lost weight following treatment of sublethal concentrations of dimethoate was found in Lab 1, but could not confirmed in Lab 2. The difference in weight between the control group and the dimethoate treatment could only be detected as a statistical significant difference in one lab at the highest concentration (0.4 mg/kg). Assessment of weight changes of parts of the bee body (honey stomach and intestine) shows a very high variation (CV) which makes interpretation of the data of the total body weight questionable. Conclusion: The results of the two laboratories were contradictory and no conclusive assessment can be done following the two sets of experiments. Assessment of bee body weight within a 10-day chronic feeding study is considered questionable for the detection of sublethal effects. Further work with other active ingredients is needed to clarify if body weight change of honey bees can be used as a parameter for sublethal effects

Proposal for a new OECD guideline for the testing of chemicals on adult honey bees (Apis mellifera L.) in a 10 day chronic feeding test in the laboratory and results of the recent ring test 2014

Background - Even though the evaluation of potential chronic oral effects on adult honey bees (Apis mellifera L.) is an integral part of the risk assessment according to e.g. the EC Regulation 1107/2009 and the EFSA Guidance Document, (EFSA 2013), there is no validated guideline available for this test system, yet. To address this new requirement and to develop a new test guideline an international ring test group was founded and a ring test was carried out in summer 2014. The ring test was carried out on the basis of a test protocol, which followed the recommendation for the proposed guideline. Results - A validity criterion for the control mortality of ≤ 15 % was met for the untreated control group in all tests and laboratories within the first run. However, for the solvent group this validity criterion could not be met in 7 out of 17 labs. In the reference item treatment group clear doseresponse correlation could be observed with the tested concentration levels and the mean LC50 and LDD50 values could be calculated, as well as the NOEC and NOEDD levels.Conclusion - The results gained in these tests indicate the suitability and reproducibility of the described test method which could serve as a basis for an official test guideline. However, the use of acetone as solvent at the tested concentration level is still questioned. Keywords: chronic toxicity, honey bee, laboratory tes

Forum: Feminism in German Studies

From Professor Wallach\u27s contribution entitled Jews and Gender : To consider Jews and gender within German Studies is to explore the evolution of German‐Jewish Studies with respect to feminist and gender studies. At times this involves looking beyond German Studies to other scholarship in Jewish gender studies, an interdisciplinary subfield in its own right. Over the past few decades, the focus on gender within German‐Jewish Studies has experienced several shifts in line with broader trends: an initial focus on the history of Jewish women and feminist movements gradually expanded to encompass the study of gender identity, masculinity, and sexuality. Historical and literary scholarly approaches now operate alongside and in dialogue with interdisciplinary scholarship in cultural studies, film and visual studies, performance studies, and other fields. [excerpt

In Situ Observations during Chemical Vapor Deposition of Hexagonal Boron Nitride on Polycrystalline Copper.

Using a combination of complementary in situ X-ray photoelectron spectroscopy and X-ray diffraction, we study the fundamental mechanisms underlying the chemical vapor deposition (CVD) of hexagonal boron nitride (h-BN) on polycrystalline Cu. The nucleation and growth of h-BN layers is found to occur isothermally, i.e., at constant elevated temperature, on the Cu surface during exposure to borazine. A Cu lattice expansion during borazine exposure and B precipitation from Cu upon cooling highlight that B is incorporated into the Cu bulk, i.e., that growth is not just surface-mediated. On this basis we suggest that B is taken up in the Cu catalyst while N is not (by relative amounts), indicating element-specific feeding mechanisms including the bulk of the catalyst. We further show that oxygen intercalation readily occurs under as-grown h-BN during ambient air exposure, as is common in further processing, and that this negatively affects the stability of h-BN on the catalyst. For extended air exposure Cu oxidation is observed, and upon re-heating in vacuum an oxygen-mediated disintegration of the h-BN film via volatile boron oxides occurs. Importantly, this disintegration is catalyst mediated, i.e., occurs at the catalyst/h-BN interface and depends on the level of oxygen fed to this interface. In turn, however, deliberate feeding of oxygen during h-BN deposition can positively affect control over film morphology. We discuss the implications of these observations in the context of corrosion protection and relate them to challenges in process integration and heterostructure CVD.P.R.K. acknowledges funding from the Cambridge Commonwealth Trust and the Lindemann Trust Fellowship. R.S.W. acknowledges a research fellowship from St. John’s College, Cambridge. S.H. acknowledges funding from ERC grant InsituNANO (no. 279342), EPSRC under grant GRAPHTED (project reference EP/K016636/1), Grant EP/H047565/1 and EU FP7 Work Programme under grant GRAFOL (project reference 285275). The European Synchrotron Radiation Facility (ESRF) is acknowledged for provision of synchrotron radiation and assistance in using beamline BM20/ROBL. We acknowledge Helmholtz-Zentrum-Berlin Electron storage ring BESSY II for synchrotron radiation at the ISISS beamline and continuous support of our experiments.This is the final version. It was first published by ACS at http://pubs.acs.org/doi/abs/10.1021/cm502603

Differential relations between two types of contact and implicit and explicit racial attitudes

Contact with out-group members has been associated with more favourable explicit attitudes towards the out-group in general, largely via the mediation of reduced intergroup anxiety. In addition, there is now a growing body of evidence suggesting that contact relates to automatically activated evaluations termed implicit attitudes. However, research has not fully illuminated the mechanisms through which contact with outgroup members impacts on implicit attitudes. A study investigating this issue assessed White participants' (N=105) explicit attitudes, implicit attitudes, intergroup anxiety, and contact quantity and quality about Asians. Greater contact quality was related to more positive explicit attitudes, while contact quantity was associated with more positive implicit attitudes. Both effects were mediated by reduced intergroup anxiety

Article Design Framework and Laboratory Experiments for Helix and Slinky Type Ground Source Heat Exchangers for Retrofitting Projects

The focus of the experimental work was on shallow spiral geothermal heat exchanger configurations. Real-scale experiments were carried out for vertically oriented spiral collectors (helix) in sand and soil. One objective was to develop a measurement concept in laboratory environment to create a framework for a validated database. This database serves as the basis for further and new development of engineering design tools. To achieve the highest possible data-point density in the observed environment, temperature sensors and a fiber-optic temperature measurement system (DTS) were used. Soil probes were taken in situ before and after the measurements and analyzed at a thermophysical laboratory to determine material properties. The heat flow was controlled by an electric heating cable, which was installed in the form of a spiral-shaped heat exchanger in a 1 m3 container. To guarantee constant boundary conditions, the measurements were carried out in a climate chamber at a defined ambient temperature. The evaluation of the transient response behavior is spatially resolved. The results are coordinate-based temperature points, which describe temperature gradients in all axes of the container over time, which are combined with known soil properties. The collected data was used to develop computational fluid dynamic (CFD) models, which are used to extend the variety of geometry and soil configurations for developing new design tools. Raw data available for download here

Circadian gene x environment perturbations influence alcohol drinking in Cryptochrome-deficient mice

Alcohol use disorder (AUD) is a widespread addiction disorder with severe consequences for health. AUD patients often suffer from sleep disturbances and irregular daily patterns. Conversely, disruptions of circadian rhythms are considered a risk factor for AUD and alcohol relapses. In this study, we investigated the extent to which circadian genetic and environmental disruptions and their interaction alter alcohol drinking behaviour in mice. As a model of genetic circadian disruption, we used Cryptochrome1/2-deficient (Cry1/2(-/-)) mice with strongly suppressed circadian rhythms and found that they exhibit significantly reduced preference for alcohol but increased incentive motivation to obtain it. Similarly, we found that low circadian SCN amplitude correlates with reduced alcohol preference in WT mice. Moreover, we show that the low alcohol preference of Cry1/2(-/-) mice concurs with high corticosterone and low levels of the orexin precursor prepro-orexin and that WT and Cry1/2(-/-) mice respond differently to alcohol withdrawal. As a model of environmentally induced disruption of circadian rhythms, we exposed mice to a "shift work" light/dark regimen, which also leads to a reduction in their alcohol preference. Interestingly, this effect is even more pronounced when genetic and environmental circadian perturbations interact in Cry1/2(-/-) mice under "shift work" conditions. In conclusion, our study demonstrates that in mice, disturbances in circadian rhythms have pronounced effects on alcohol consumption as well as on physiological factors and other behaviours associated with AUD and that the interaction between circadian genetic and environmental disturbances further alters alcohol consumption behaviour