Electrical detection of magnetic skyrmions by non-collinear magnetoresistance

Magnetic skyrmions are localised non-collinear spin textures with high potential for future spintronic applications. Skyrmion phases have been discovered in a number of materials and a focus of current research is the preparation, detection, and manipulation of individual skyrmions for an implementation in devices. Local experimental characterization of skyrmions has been performed by, e.g., Lorentz microscopy or atomic-scale tunnel magnetoresistance measurements using spin-polarised scanning tunneling microscopy. Here, we report on a drastic change of the differential tunnel conductance for magnetic skyrmions arising from their non-collinearity: mixing between the spin channels locally alters the electronic structure, making a skyrmion electronically distinct from its ferromagnetic environment. We propose this non-collinear magnetoresistance (NCMR) as a reliable all-electrical detection scheme for skyrmions with an easy implementation into device architectures

Pervasive transition of the Brazilian land-use system

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Mapping native and non-native vegetation in the Brazilian Cerrado using freely available satellite products

This is the final version. Available on open access from Nature Research via the DOI in this recordNative vegetation across the Brazilian Cerrado is highly heterogeneous and biodiverse and provides important ecosystem services, including carbon and water balance regulation, however, land-use changes have been extensive. Conservation and restoration of native vegetation is essential and could be facilitated by detailed landcover maps. Here, across a large case study region in Goiás State, Brazil (1.1 Mha), we produced physiognomy level maps of native vegetation (n = 8) and other landcover types (n = 5). Seven different classification schemes using different combinations of input satellite imagery were used, with a Random Forest classifier and 2-stage approach implemented within Google Earth Engine. Overall classification accuracies ranged from 88.6-92.6% for native and non-native vegetation at the formation level (stage-1), and 70.7-77.9% for native vegetation at the physiognomy level (stage-2), across the seven different classifications schemes. The differences in classification accuracy resulting from varying the input imagery combination and quality control procedures used were small. However, a combination of seasonal Sentinel-1 (C-band synthetic aperture radar) and Sentinel-2 (surface reflectance) imagery resulted in the most accurate classification at a spatial resolution of 20 m. Classification accuracies when using Landsat-8 imagery were marginally lower, but still reasonable. Quality control procedures that account for vegetation burning when selecting vegetation reference data may also improve classification accuracy for some native vegetation types. Detailed landcover maps, produced using freely available satellite imagery and upscalable techniques, will be important tools for understanding vegetation functioning at the landscape scale and for implementing restoration projects.ShellFAPESPNatural Environment Research Council (NERC

Performance of the CMS Cathode Strip Chambers with Cosmic Rays

The Cathode Strip Chambers (CSCs) constitute the primary muon tracking device in the CMS endcaps. Their performance has been evaluated using data taken during a cosmic ray run in fall 2008. Measured noise levels are low, with the number of noisy channels well below 1%. Coordinate resolution was measured for all types of chambers, and fall in the range 47 microns to 243 microns. The efficiencies for local charged track triggers, for hit and for segments reconstruction were measured, and are above 99%. The timing resolution per layer is approximately 5 ns

A Heterogeneous In Vitro Three Dimensional Model of Tumour-Stroma Interactions Regulating Sprouting Angiogenesis

Angiogenesis, the formation of new blood vessels, is an essential process for tumour progression and is an area of significant therapeutic interest. Different in vitro systems and more complex in vivo systems have been described for the study of tumour angiogenesis. However, there are few human 3D in vitro systems described to date which mimic the cellular heterogeneity and complexity of angiogenesis within the tumour microenvironment. In this study we describe the Minitumour model – a 3 dimensional human spheroid-based system consisting of endothelial cells and fibroblasts in co-culture with the breast cancer cell line MDA-MB-231, for the study of tumour angiogenesis in vitro. After implantation in collagen-I gels, Minitumour spheroids form quantifiable endothelial capillary-like structures. The endothelial cell pre-capillary sprouts are supported by the fibroblasts, which act as mural cells, and their growth is increased by the presence of cancer cells. Characterisation of the Minitumour model using small molecule inhibitors and inhibitory antibodies show that endothelial sprout formation is dependent on growth factors and cytokines known to be important for tumour angiogenesis. The model also shows a response to anti-angiogenic agents similar to previously described in vivo data. We demonstrate that independent manipulation of the different cell types is possible, using common molecular techniques, before incorporation into the model. This aspect of Minitumour spheroid analysis makes this model ideal for high content studies of gene function in individual cell types, allowing for the dissection of their roles in cell-cell interactions. Finally, using this technique, we were able to show the requirement of the metalloproteinase MT1-MMP in endothelial cells and fibroblasts, but not cancer cells, for sprouting angiogenesis

Anxiety and depression symptoms in women with and without binge eating disorder enrolled in weight loss programs

OBJECTIVES: 1) To investigate the association between binge eating scores, anxiety and depression symptoms, and body mass index (BMI), and 2) to assess the presence of differences in severity of anxiety symptoms, severity of depression symptoms, and BMI in women with and without binge eating disorder. METHOD: The sample comprised 113 women aged between 22 and 60 years (39.35±10.85) enrolled in weight loss programs in Porto Alegre, southern Brazil. The following instruments were used: structured interview, Brazilian Economic Classification Criteria, Beck Anxiety Inventory, Beck Depression Inventory, and Binge Eating Scale. Data were analyzed using descriptive and inferential statistics. RESULTS: A positive association was found between binge eating scores and the severity of anxiety symptoms (p OBJETIVOS: 1) Investigar a associação entre escores de compulsão alimentar, sintomas de ansiedade e de depressão e índice de massa corporal (IMC); e 2) verificar se existe diferença na intensidade dos sintomas de ansiedade, dos sintomas depressivos e no IMC em mulheres com e sem compulsão alimentar. MÉTODO: A amostra foi composta de 113 mulheres com idade entre 22 e 60 anos (39,35±10,85), participantes de programas de redução de peso na cidade de Porto Alegre, sul do Brasil. Foram aplicados os seguintes instrumentos: entrevista estruturada, Critérios de Classificação Econômica Brasil, Inventário de Ansiedade de Beck, Inventário de Depressão de Beck e Escala de Compulsão Alimentar Periódica. Os dados foram analisados utilizando-se estatística descritiva e inferencial. RESULTADOS: Houve associação positiva entre os escores de compulsão alimentar e a intensidade dos sintomas de ansiedade (p < 0,001) e de depressão (p < 0,001). Não foi observada associação significativa (p = 0,341) entre IMC e escores de compulsão alimentar. Houve diferença significativa entre mulheres com e sem compulsão alimentar com relação à intensidade dos sintomas de ansiedade (p < 0,001) e depressão (p < 0,001). Não foi encontrada diferença significativa entre os grupos com relação ao IMC (p = 0,103). CONCLUSÃO: Os achados deste estudo mostraram que a compulsão alimentar está associada a sintomas de ansiedade e de depressão, porém não está associada ao IMC