Unidirectional spin Hall magnetoresistance in ferromagnet/normal metal bilayers

Magnetoresistive effects are usually invariant upon inversion of the magnetization direction. In noncentrosymmetric conductors, however, nonlinear resistive terms can give rise to a current dependence that is quadratic in the applied voltage and linear in the magnetization. Here we demonstrate that such conditions are realized in simple bilayer metal films where the spin-orbit interaction and spin-dependent scattering couple the current-induced spin accumulation to the electrical conductivity. We show that the longitudinal resistance of Ta|Co and Pt|Co bilayers changes when reversing the polarity of the current or the sign of the magnetization. This unidirectional magnetoresistance scales linearly with current density and has opposite sign in Ta and Pt, which we associate with the modification of the interface scattering potential induced by the spin Hall effect in these materials. Our results suggest a route to control the resistance and detect magnetization switching in spintronic devices using a two-terminal geometry, which applies also to heterostructures including topological insulators

Breakdown of the Korringa Law of Nuclear Spin Relaxation in Metallic GaAs

We present nuclear spin relaxation measurements in GaAs epilayers using a new pump-probe technique in all-electrical, lateral spin-valve devices. The measured T1 times agree very well with NMR data available for T > 1 K. However, the nuclear spin relaxation rate clearly deviates from the well-established Korringa law expected in metallic samples and follows a sub-linear temperature dependence 1/T1 ~ T^0.6 for 0.1 K < T < 10 K. Further, we investigate nuclear spin inhomogeneities.Comment: 5 pages, 4 (color) figures. arXiv admin note: text overlap with arXiv:1109.633

Targeting BTK for the treatment of FLT3-ITD mutated acute myeloid leukemia

Approximately 20% of patients with acute myeloid leukaemia (AML) have a mutation in FMS-like-tyrosine-kinase-3 (FLT3). FLT3 is a trans-membrane receptor with a tyrosine kinase domain which, when activated, initiates a cascade of phosphorylated proteins including the SRC family of kinases. Recently our group and others have shown that pharmacologic inhibition and genetic knockdown of Bruton's tyrosine kinase (BTK) blocks AML blast proliferation, leukaemic cell adhesion to bone marrow stromal cells as well as migration of AML blasts. The anti-proliferative effects of BTK inhibition in human AML are mediated via inhibition of downstream NF-κB pro-survival signalling however the upstream drivers of BTK activation in human AML have yet to be fully characterised. Here we place the FLT3-ITD upstream of BTK in AML and show that the BTK inhibitor ibrutinib inhibits the survival and proliferation of FLT3-ITD primary AML blasts and AML cell lines. Furthermore ibrutinib inhibits the activation of downstream kinases including MAPK, AKT and STAT5. In addition we show that BTK RNAi inhibits proliferation of FLT3-ITD AML cells. Finally we report that ibrutinib reverses the cyto-protective role of BMSC on FLT3-ITD AML survival. These results argue for the evaluation of ibrutinib in patients with FLT3-ITD mutated AML

Childhood socioeconomic position and objectively measured physical capability levels in adulthood: a systematic review and meta-analysis

&lt;p&gt;&lt;b&gt;Background:&lt;/b&gt; Grip strength, walking speed, chair rising and standing balance time are objective measures of physical capability that characterise current health and predict survival in older populations. Socioeconomic position (SEP) in childhood may influence the peak level of physical capability achieved in early adulthood, thereby affecting levels in later adulthood. We have undertaken a systematic review with meta-analyses to test the hypothesis that adverse childhood SEP is associated with lower levels of objectively measured physical capability in adulthood.&lt;/p&gt; &lt;p&gt;&lt;b&gt;Methods and Findings:&lt;/b&gt; Relevant studies published by May 2010 were identified through literature searches using EMBASE and MEDLINE. Unpublished results were obtained from study investigators. Results were provided by all study investigators in a standard format and pooled using random-effects meta-analyses. 19 studies were included in the review. Total sample sizes in meta-analyses ranged from N = 17,215 for chair rise time to N = 1,061,855 for grip strength. Although heterogeneity was detected, there was consistent evidence in age adjusted models that lower childhood SEP was associated with modest reductions in physical capability levels in adulthood: comparing the lowest with the highest childhood SEP there was a reduction in grip strength of 0.13 standard deviations (95% CI: 0.06, 0.21), a reduction in mean walking speed of 0.07 m/s (0.05, 0.10), an increase in mean chair rise time of 6% (4%, 8%) and an odds ratio of an inability to balance for 5s of 1.26 (1.02, 1.55). Adjustment for the potential mediating factors, adult SEP and body size attenuated associations greatly. However, despite this attenuation, for walking speed and chair rise time, there was still evidence of moderate associations.&lt;/p&gt; &lt;p&gt;&lt;b&gt;Conclusions:&lt;/b&gt; Policies targeting socioeconomic inequalities in childhood may have additional benefits in promoting the maintenance of independence in later life.&lt;/p&gt

Darwin wasps: a new name heralds renewed efforts to unravel the evolutionary history of Ichneumonidae

The parasitoid wasp family Ichneumonidae is arguably one of the groups for which current knowledge lags most strongly behind their enormous diversity. In a five-day meeting in Basel (Switzerland) in June 2019, 22 researchers from 14 countries met to discuss the most important issues in ichneumonid research, including increasing the speed of species discovery, resolving higher-level relationships, and studying the radiation of these parasitoids onto various host groups through time. All agreed that it is time to advertise ichneumonid research more broadly and thereby attract young talents to this group for which specialists are sorely lacking, as well as increase public awareness about their exciting biology and ecological impact. In order to popularize the group, we here suggest a new vernacular name for the family, “Darwin wasps”, to reflect the pivotal role they played in convincing Charles Darwin that not all of creation could have been created by a benevolent god. We hope that the name catches on, and that Darwin wasps start buzzing more loudly across all disciplines of biology

Frequency and genotypic distribution of GB virus C (GBV-C) among Colombian population with Hepatitis B (HBV) or Hepatitis C (HCV) infection

<p>Abstract</p> <p>Background</p> <p>GB virus C (GBV-C) is an enveloped positive-sense ssRNA virus belonging to the <it>Flaviviridae </it>family. Studies on the genetic variability of the GBV-C reveals the existence of six genotypes: genotype 1 predominates in West Africa, genotype 2 in Europe and America, genotype 3 in Asia, genotype 4 in Southwest Asia, genotype 5 in South Africa and genotype 6 in Indonesia. The aim of this study was to determine the frequency and genotypic distribution of GBV-C in the Colombian population.</p> <p>Methods</p> <p>Two groups were analyzed: i) 408 Colombian blood donors infected with HCV (n = 250) and HBV (n = 158) from Bogotá and ii) 99 indigenous people with HBV infection from Leticia, Amazonas. A fragment of 344 bp from the 5' untranslated region (5' UTR) was amplified by nested RT PCR. Viral sequences were genotyped by phylogenetic analysis using reference sequences from each genotype obtained from GenBank (n = 160). Bayesian phylogenetic analyses were conducted using Markov chain Monte Carlo (MCMC) approach to obtain the MCC tree using BEAST v.1.5.3.</p> <p>Results</p> <p>Among blood donors, from 158 HBsAg positive samples, eight 5.06% (n = 8) were positive for GBV-C and from 250 anti-HCV positive samples, 3.2%(n = 8) were positive for GBV-C. Also, 7.7% (n = 7) GBV-C positive samples were found among indigenous people from Leticia. A phylogenetic analysis revealed the presence of the following GBV-C genotypes among blood donors: 2a (41.6%), 1 (33.3%), 3 (16.6%) and 2b (8.3%). All genotype 1 sequences were found in co-infection with HBV and 4/5 sequences genotype 2a were found in co-infection with HCV. All sequences from indigenous people from Leticia were classified as genotype 3. The presence of GBV-C infection was not correlated with the sex (p = 0.43), age (p = 0.38) or origin (p = 0.17).</p> <p>Conclusions</p> <p>It was found a high frequency of GBV-C genotype 1 and 2 in blood donors. The presence of genotype 3 in indigenous population was previously reported from Santa Marta region in Colombia and in native people from Venezuela and Bolivia. This fact may be correlated to the ancient movements of Asian people to South America a long time ago.</p

First case of Anaplasma platys infection in a dog from Croatia

<p>Abstract</p> <p>Background</p> <p>It is known that <it>Anaplasma (A.) platys</it>, the causative agent of infectious canine cyclic thrombocytopenia, is endemic in countries of the Mediterranean basin. However, few reports are available from the Balkans. This case report describes a dog, which was imported from Croatia to Germany in May 2010. One month later the dog was presented to a local veterinarian in Germany due to intermittent/recurrent diarrhoea. Diagnostic tests were performed to identify infections caused by <it>Anaplasma </it>spp., <it>Ehrlichia </it>spp., <it>Hepatozoon canis, Babesia </it>spp., <it>Leishmania </it>spp., <it>Borrelia burgdorferi </it>and/or <it>Dirofilaria immitis</it>.</p> <p>Findings</p> <p>Haematological examination of a blood smear revealed basophilic inclusions in thrombocytes, which were confirmed as <it>A. platys </it>with a species-specific real-time PCR. Additionally, an infection with <it>Babesia (B.) vogeli </it>was also detected (PCR and serology). No specific antibodies against <it>Anaplasma </it>antigen were detectable. Although the dog showed no specific clinical signs, thrombocytopenia, anaemia and elevated C-reactive protein (CRP) were observed. Sequencing of a 1,348-bp partial ribosomal RNA gene revealed highest homology to <it>A. platys </it>sequences from Thailand, Japan and France.</p> <p>Conclusions</p> <p><it>A. platys </it>was detected for first time in a dog imported from Croatia. As the dog was also co-infected by <it>B. vogeli</it>, unique serological and haematological findings were recorded. Thrombocytopenia, anaemia and elevated values of C-reactive protein were the laboratory test abnormalities observed in this case. <it>A. platys </it>infections should be considered in dogs coming from Croatia and adjacent regions.</p