640 research outputs found

    Walter Campbell:A distinguished life

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    An efficient and simple synthesis approach to form stable (68) Ga-labeled nanogels is reported and their fundamental properties investigated. Nanogels are obtained by self-assembly of amphiphilic statistical prepolymers derivatised with chelating groups for radiometals. The resulting nanogels exhibit a well-defined spherical shape with a diameter of 290 +/- 50 nm. The radionuclide (68) Ga is chelated in high radiochemical yields in an aqueous medium at room temperature. The phagocytosis assay demonstrates a highly increased internalization of nanogels by activated macrophages. Access to these (68) Ga-nanogels will allow the investigation of general behavior and clearance pathways of nanogels in vivo by nuclear molecular imaging

    A Comprehensive Measure of Attitudes and Behaviour: Development of the Support for Gender Equality among Men Scale (article)

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    This is the final version. Available on open access from Wiley via the DOI in this recordThe datasets associated with this article are located in ORE at: https://doi.org/10.24378/exe.1805, https://doi.org/10.24378/exe.1806, https://doi.org/10.24378/exe.1807, https://doi.org/10.24378/exe.1808, and https://doi.org/10.24378/exe.1809In this paper, we develop and validate the 16-item Support for Gender Equality among Men Scale (SGEMS) across four studies. Drawing on exploratory (Study 1, n = 322) and confirmatory (Study 2, n = 358; Study 4, n = 192) factor analysis, we determine a two-factor structure: public and domestic support for gender equality. In Study 3 (n = 146) and Study 4, we validate the scale by establishing its relationship with, among others, several prominent measures of sexism, a behavioural measure, and social desirability. The scale fills a psychometric gap in the literature: To date, no validated measure of support for gender equality, measuring both attitudes and behavioural intentions and focusing specifically on men, exists. Considering the recent increase in interest in men as allies of the feminist movement the scale functions as a useful tool to explore the topic in depth in future research.Economic and Social Research Council (ESRC

    Microscopic nanomechanical dissipation in gallium arsenide resonators

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    We report on a systematic study of nanomechanical dissipation in high-frequency (approximatively 300 MHz) gallium arsenide optomechanical disk resonators, in conditions where clamping and fluidic losses are negligible. Phonon-phonon interactions are shown to contribute with a loss background fading away at cryogenic temperatures (3 K). Atomic layer deposition of alumina at the surface modifies the quality factor of resonators, pointing towards the importance of surface dissipation. The temperature evolution is accurately fitted by two-level systems models, showing that nanomechanical dissipation in gallium arsenide resonators directly connects to their microscopic properties. Two-level systems, notably at surfaces, appear to rule the damping and fluctuations of such high-quality crystalline nanomechanical devices, at all temperatures from 3 to 300K

    360-degree Video Stitching for Dual-fisheye Lens Cameras Based On Rigid Moving Least Squares

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    Dual-fisheye lens cameras are becoming popular for 360-degree video capture, especially for User-generated content (UGC), since they are affordable and portable. Images generated by the dual-fisheye cameras have limited overlap and hence require non-conventional stitching techniques to produce high-quality 360x180-degree panoramas. This paper introduces a novel method to align these images using interpolation grids based on rigid moving least squares. Furthermore, jitter is the critical issue arising when one applies the image-based stitching algorithms to video. It stems from the unconstrained movement of stitching boundary from one frame to another. Therefore, we also propose a new algorithm to maintain the temporal coherence of stitching boundary to provide jitter-free 360-degree videos. Results show that the method proposed in this paper can produce higher quality stitched images and videos than prior work.Comment: Preprint versio

    Influence of deformation axis onto the length free path of screw dislocations in pure fcc materials

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    In this paper the influence of crystal's deformation axis orientation on formation of long, strong dislocation junctions which can be barriers that limit the shear zone has been studied. The probability of strong junctions formation has been obtained on the basis of interdislocation contact interactions model. The length of free path of screw dislocations has been defined for different orientations of crystal's deformation axis

    Correlation of dynamic contrast-enhanced bone perfusion with morphologic ultra-short echo time MR imaging in medication-related osteonecrosis of the jaw

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    OBJECTIVES: To investigate whether dynamic contrast-enhanced (DCE)-MR bone perfusion could serve as surrogate for morphologic ultra-short echo time (UTE) bone images and to correlate perfusion with morphologic hallmarks in histologically proven foci of medication-related osteonecrosis of the jaw (MRONJ). METHODS: Retrospective study including 20 patients with established diagnosis of MRONJ. Qualitative consensus assessment of predefined jaw regions by two radiologists was used as reference standard using Likert scale (0-3) for standard imaging hallmarks in MRONJ (osteolysis, sclerosis, periosteal thickening). DCE-MRI measurements performed in corresponding regions of the mandible were then correlated with qualitative scores. Regions were grouped into "non-affected" and "pathologic" based on binarized Likert scores of different imaging hallmarks (0-1 vs 2-3). DCE-MRI measurements among hallmarks were compared using Mann-Whitney-U-testing. ROC (receiver-operating-characteristic) analysis was performed for each of the perfusion parameters to assess diagnostic performance for identification of MRONJ using morphologic ratings as reference standard. RESULTS: Median perfusion measurements of "pathologic" regions in wash-in, peak enhancement intensity and integrated area under the curve are significantly higher than those of "non-affected" regions, irrespective of reference imaging hallmark (p < 0.05). No significant perfusion differences were found between "pathologic" regions with and without osteolysis (p = 0.180). ROC analysis showed fair diagnostic performance of DCE-MRI parameters for identification of MRONJ (AUC 0.626-0.727). CONCLUSIONS: DCE bone perfusion parameters are significantly increased in MRONJ compared to non-affected regions, irrespective of osteolysis. Due to certain overlap DCE-MRI bone perfusion cannot serve as full surrogate for UTE bone imaging but may enhance reader confidence

    The who, when, and why of the glass cliff phenomenon: A meta-analysis of appointments to precarious leadership positions

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    This is the author accepted manuscript. The final version is available from the American Psychological Association via the DOI in this recordData availability: The data sets, analysis code, and codebook for analyses are available at https://osf.io/b8tzq/?view_only=6aad2cc8f1ba4041bcd2cc48e44cb4aaWomen and members of other underrepresented groups who break through the glass ceiling often find themselves in precarious leadership positions, a phenomenon that has been termed the glass cliff. The glass cliff has been investigated in a range of domains using various methodologies, but evidence is mixed. In three meta analyses, we examined (a) archival field studies testing whether members of underrepresented groups, compared to members of majority groups, are more likely to be appointed to leadership positions in times of crisis; (b) experimental studies testing whether members of underrepresented groups, compared to members of majority groups, are evaluated as more suitable for, as well as (c) more likely to be selected for, leadership positions in times of crisis. All three analyses provided some evidence in line with the glass cliff for women. Specifically, the meta-analysis of archival studies revealed a small glass cliff effect that was dependent on organizational domain. The leadership suitability meta-analysis also showed a small glass cliff effect in between-participants studies, but not in within-participants studies. The analysis of leadership selection revealed that women are more likely to be selected over men in times of crisis, and that this effect is larger in countries with higher gender inequality. The glass cliff also extended to members of underrepresented racial and ethnic groups. We explore several moderating factors and report analyses shedding light on the underlying causes of the glass cliff. We discuss implications of our findings as well as open questions.Economic and Social Research Council (ESRC)European Commissio

    Increased reliance on coronary perfusion for cardiorespiratory performance in seawater-acclimated rainbow trout

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    Salmonid ventricles are composed of spongy and compact myocardium, the latter being perfused via a coronary circulation. Rainbow trout (Oncorhynchus mykiss) acclimated to sea water have higher proportions of compact myocardium and display stroke volume-mediated elevations in resting cardiac output relative to freshwater-acclimated trout, probably to meet the higher metabolic needs of osmoregulatory functions. Here, we tested the hypothesis that cardiorespiratory performance of rainbow trout in sea water is more dependent on coronary perfusion by assessing the effects of coronary ligation on cardiorespiratory function in resting and exhaustively exercised trout acclimated to fresh water or sea water. While ligation only had minor effects on resting cardiorespiratory function across salinities, cardiac function after chasing to exhaustion was impaired, presumably as a consequence of atrioventricular block. Ligation reduced maximum O2 consumption rate by 33% and 17% in fish acclimated to sea water and fresh water, respectively, which caused corresponding 41% and 17% reductions in aerobic scope. This was partly explained by different effects on cardiac performance, as maximum stroke volume was only significantly impaired by ligation in sea water, resulting in 38% lower maximum cardiac output in seawater compared with 28% in fresh water. The more pronounced effect on respiratory performance in sea water was presumably also explained by lower blood O2 carrying capacity, with ligated seawater-acclimated trout having 16% and 17% lower haemoglobin concentration and haematocrit, respectively, relative to ligated freshwater trout. In conclusion, we show that the coronary circulation allows seawater-acclimated trout to maintain aerobic scope at a level comparable to that in fresh water
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