Self-current induced spin-orbit torque in FeMn/Pt multilayers

Extensive efforts have been devoted to the study of spin-orbit torque in ferromagnetic metal/heavy metal bilayers and exploitation of it for magnetization switching using an in-plane current. As the spin-orbit torque is inversely proportional to the thickness of the ferromagnetic layer, sizable effect has only been realized in bilayers with an ultrathin ferromagnetic layer. Here we demonstrate that, by stacking ultrathin Pt and FeMn alternately, both ferromagnetic properties and current induced spin-orbit torque can be achieved in FeMn/Pt multilayers without any constraint on its total thickness. The critical behavior of these multilayers follows closely three-dimensional Heisenberg model with a finite Curie temperature distribution. The spin torque effective field is about 4 times larger than that of NiFe/Pt bilayer with a same equivalent NiFe thickness. The self-current generated spin torque is able to switch the magnetization reversibly without the need for an external field or a thick heavy metal layer. The removal of both thickness constraint and necessity of using an adjacent heavy metal layer opens new possibilities for exploiting spin-orbit torque for practical applications.Comment: 28 pages, 5 figure

Using the Internet to Create Positive Social Changes: Case Studies in China

In recent years, companies have been increasingly under pressure to deliver programs that can create both business value and social value. Building on the positive social change framework developed by Stephan et al., this paper uses two case studies (Gongyi Baobei and Jutudi) of the Alibaba Group, a leading Internet company in China, to investigate how companies can use the Internet to bring about positive social changes (PSC) to target groups. Our focus is placed on the nature of projects, i.e., surface-level and deep-level PSC projects. Our decision to use different case studies from the same company is based on the assumption that the enabling effects of internal organizational practices should be similar. To be more specific, we want to study the link between PSC projects and the company’s existing businesses, the role of the Internet in raising customers’ awareness and participation in the programs, and the change mechanism designed and implemented to bring positive social changes to customers. Data were collected through interviews and literature review. Our research provides empirical evidence to show a deep-level PSC project (i.e., Jutudi) can be very different from a surface-level PSC project (i.e., Gongyi Baobei) in terms of the reliance on existing business operations and the design of change mechanisms. Our research limitations and direction for future research will also be discussed

The Effects Of Malfunctioning Personalized Services On Users’ Trust And Behaviors

Online merchants adopt web personalization to customize web content to match online users’ needs. Prior research has only looked at the “success” side of web personalization. Little research examines the “problematic” side of web personalization. The objective of this research is to explore how “malfunctioning” personalized web services influence an online user’s trust in the personalization agent and the behavioral intention of that user. In particular, this research looks at two types of malfunctioning personalization: irrelevant recommendations and biased recommendations. We draw on trust theories to develop seven hypotheses to predict the effects of malfunctioning personalized web services. We conducted a study with a personalized music download website. We found that irrelevant recommendations led to low trust in the personalization agent’s competence and integrity, and biased recommendations led to low trust in the integrity of the personalization agent. These findings provide empirical evidence of the possible problems of malfunctioning personalization and help firms understand and quantify the challenges and limitations of incorporating web personalization in their websites

Use of type I interferon-inducible mRNAs as pharmacodynamic markers and potential diagnostic markers in trials with sifalimumab, an anti-IFNα antibody, in systemic lupus erythematosus

Type I interferons are implicated in the pathogenesis of systemic lupus erythematosus (SLE). Type I interferon-inducible mRNAs are widely and concordantly overexpressed in the periphery and involved tissues of a subset of SLE patients, and provide utility as pharmacodynamic biomarkers to aid dose selection, as well as potential indicators of patients who might respond favorably to anti-IFNα therapy in SLE. We implemented a three-tiered approach to identify a panel of type I interferon-inducible mRNAs to be used as potential pharmacodynamic biomarkers to aid dose selection in clinical trials of sifalimumab, an anti-IFNα monoclonal antibody under development for the treatment of SLE. In a single-dose escalation phase 1 trial, we observed a sifalimumab-specific and dose-dependent inhibition of the overexpression of type I interferon-inducible mRNAs in the blood of treated subjects. Inhibition of expression of type I interferon-inducible mRNAs and proteins was also observed in skin lesions of SLE subjects from the same trial. Inhibiting IFNα resulted in a profound downstream effect in these SLE subjects that included suppression of mRNAs of B-cell activating factor belonging to the TNF family and the signaling pathways of TNFα, IL-10, IL-1β, and granulocyte-macrophage colony-stimulating factor in both the periphery and skin lesions. A scoring method based on the expression of type I interferon-inducible mRNAs partitioned SLE patients into two distinct subpopulations, which suggests the possibility of using these type I interferon-inducible genes as predictive biomarkers to identify SLE patients who might respond more favorably to anti-type I interferon therapy

Artificial Synthesis of Conserved Segment S Gene Fragment of Rift Valley Fever Virus and Preliminary Study of Its Reverse Transcription Loop-Mediated Isothermal Amplification Detection Method

Purpose: To develop a rapid detection method for Rift Valley fever virus (RVFV) diagnosis.Methods: According to the reference sequences of RVFV published in GenBank, nine overlapping polymerase chain reaction (PCR) primers and four specific reverse transcription loop-mediated isothermal amplification (RT-LAMP) primers were designed using DNAStar and LAMP primer design software, respectively. Based on the synthesis of a conserved part of the RVFV S segment gene sequence using overlapping PCR, RT-LAMP assay was first established and evaluated after a series of tests, including, optimization of reaction conditions, and sensitivity and specificity tests.Result: A target RVFV S segment gene fragment of 288 bp was synthesised. The optimal reaction conditions for RT-LAMP assay were 63 °C for 45 min: the assay has a specific ladder-like pattern of amplification bands from about 120 bp. The lowest target gene copy number of RT-LAMP for RVFV detection was 70 copies. The assay showed good specificity as only the synthesised target RVFV gene was amplified with no amplification for the detection of Peste des petits ruminants virus, Epidemic encephalitis B virus, E. coli, Pasteurella multocida, or Salmonella.Conclusion: This study provides a rapid, sensitive, specific RT-LAMP method for RVFV detection.Keywords: Rift valley fever virus, Overlapping polymerase chain reaction, Reverse transcription loopmediated isothermal amplification, Rapid diagnosis tes

The contamination of Vibrio spp. of seashell products in 5 cities of Guangxi in 2017

Objective To determine the contamination of Vibrio parahaemolyticus, Vibrio vulnificus, Vibrio alginolyticus and Vibrio cholera in seashell products. Methods Seashell samples were collected from three coastal cities and two inland cities of Guangxi in 2017. Results There were 800 samples were collected. The total positive rate of Vibrio spp. was 76.5% (612/800). The positive rate of Vibrio parahaemolyticus, Vibrio vulnificus and Vibrio cholera were 73.9% (591/800), 18.4% (147/800) and 0.1% (1/800), respectively. There was no Vibrio alginolyticus detected. For Vibrio parahaemolyticus, the positive rate was related to the samples source, samples status and the species of seashell. The positive rate in coastal areas was higher than inland areas, while the quantity was lower. Both the positive rate and quantity of Vibrio spp. in the live products were higher than fresh/chilled products. The positive rate of razor fish, mud clam, oyster and short necked clam were the highest and all above 75.0%. The positive rate of scallop and mussel was relatively low but the quantity was the highest. Around 1.0% (6/591) of the Vibrio parahaemolyticus positive samples was detected virulence genes. For the Vibrio vulnificus, the positive rate in rural areas was higher than urban areas, and coastal areas was higher than inland areas. The positive rate of razor fish and mud clam was the highest and both over 35.0%. Conclusion Vibrio parahaemolyticus and Vibrio vulnificus were highly contaminated in seashell products in Guangxi. It is necessary to strengthen the health education of food safety and the surveillance of Vibrio vulnificus in coastal rural areas

Loss of Conformational Stability in Calmodulin upon Methionine Oxidation

We have used electrospray ionization mass spectrometry (ESI-MS), circular dichroism (CD), and fluorescence spectroscopy to investigate the secondary and tertiary structural consequences that result from oxidative modification of methionine residues in wheat germ calmodulin (CaM), and prevent activation of the plasma membrane Ca-ATPase. Using ESI-MS, we have measured rates of modification and molecular mass distributions of oxidatively modified CaM species (CaMox) resulting from exposure to H2O2. From these rates, we find that oxidative modification of methionine to the corresponding methionine sulfoxide does not predispose CaM to further oxidative modification. These results indicate that methionine oxidation results in no large-scale alterations in the tertiary structure of CaMox, because the rates of oxidative modification of individual methionines are directly related to their solvent exposure. Likewise, CD measurements indicate that methionine oxidation results in little change in the apparent α-helical content at 28°C, and only a small (0.3 ± 0.1 kcal mol−1) decrease in thermal stability, suggesting the disruption of a limited number of specific noncovalent interactions. Fluorescence lifetime, anisotropy, and quenching measurements of N-(1-pyrenyl)-maleimide (PMal) covalently bound to Cys26 indicate local structural changes around PMal in the amino-terminal domain in response to oxidative modification of methionine residues in the carboxyl-terminal domain. Because the opposing globular domains remain spatially distant in both native and oxidatively modified CaM, the oxidative modification of methionines in the carboxyl-terminal domain are suggested to modify the conformation of the amino-terminal domain through alterations in the structural features involving the interdomain central helix. The structural basis for the linkage between oxidative modification and these global conformational changes is discussed in terms of possible alterations in specific noncovalent interactions that have previously been suggested to stabilize the central helix in CaM

Field-like spin orbit torque in ultra-thin polycrystalline FeMn films

Field-like spin orbit torque in FeMn/Pt bilayers with ultra-thin polycrystalline FeMn has been characterized through planar Hall effect measurements. A large effective field is obtained for FeMn in the thickness range of 2 to 5 nm. The experimental observations can be reasonably accounted for by using a macro-spin model under the assumption that the FeMn layer is composed of two spin sublattices with unequal magnetizations. The large effective field corroborates the spin Hall origin of the effective field considering the much smaller uncompensated net moments in FeMn as compared to NiFe. The effective absorption of spin current by FeMn is further confirmed by the fact that spin current generated by Pt in NiFe/FeMn/Pt trilayers can only travel through the FeMn layer with a thickness of 1 to 4 nm. By quantifying the field-like effective field induced in NiFe, a spin diffusion length of 2 nm is estimated in FeMn, in consistence with values reported in literature by ferromagnetic resonance and spin-pumping experiments.Comment: 37 pages, 12 figure

Genomic Signatures Characterize Leukocyte Infiltration in Myositis Muscles

Background: Leukocyte infiltration plays an important role in the pathogenesis and progression of myositis, and is highly associated with disease severity. Currently, there is a lack of: efficacious therapies for myositis; understanding of the molecular features important for disease pathogenesis; and potential molecular biomarkers for characterizing inflammatory myopathies to aid in clinical development. Methods: In this study, we developed a simple model and predicted that 1) leukocyte-specific transcripts (including both protein-coding transcripts and microRNAs) should be coherently overexpressed in myositis muscle and 2) the level of over-expression of these transcripts should be correlated with leukocyte infiltration. We applied this model to assess immune cell infiltration in myositis by examining mRNA and microRNA (miRNA) expression profiles in muscle biopsies from 31 myositis patients and 5 normal controls. Results: Several gene signatures, including a leukocyte index, type 1 interferon (IFN), MHC class I, and immunoglobulin signature, were developed to characterize myositis patients at the molecular level. The leukocyte index, consisting of genes predominantly associated with immune function, displayed strong concordance with pathological assessment of immune cell infiltration. This leukocyte index was subsequently utilized to differentiate transcriptional changes due to leukocyte infiltration from other alterations in myositis muscle. Results from this differentiation revealed biologically relevant differences in the relationship between the type 1 IFN pathway, miR-146a, and leukocyte infiltration within various myositis subtypes. Conclusions: Results indicate that a likely interaction between miR-146a expression and the type 1 IFN pathway is confounded by the level of leukocyte infiltration into muscle tissue. Although the role of miR-146a in myositis remains uncertain, our results highlight the potential benefit of deconvoluting the source of transcriptional changes in myositis muscle or other heterogeneous tissue samples. Taken together, the leukocyte index and other gene signatures developed in this study may be potential molecular biomarkers to help to further characterize inflammatory myopathies and aid in clinical development. These hypotheses need to be confirmed in separate and sufficiently powered clinical trials