Nonequilibrium spin injection in monolayer black phosphorus

Monolayer black phosphorus (MBP) is an interesting emerging electronic material with a direct band gap and relatively high carrier mobility. In this work we report a theoretical investigation of nonequilibrium spin injection and spin-polarized quantum transport in MBP from ferromagnetic Ni contacts, in two-dimensional magnetic tunneling structures. We investigate physical properties such as the spin injection efficiency, the tunnel magnetoresistance ratio, spin-polarized currents, charge currents and transmission coefficients as a function of external bias voltage, for two different device contact structures where MBP is contacted by Ni(111) and by Ni(100). While both structures are predicted to give respectable spin-polarized quantum transport, the Ni(100)/MBP/Ni(100) trilayer has the superior properties where the spin injection and magnetoresistance ratio maintains almost a constant value against the bias voltage. The nonequilibrium quantum transport phenomenon is understood by analyzing the transmission spectrum at nonequilibrium.Comment: 6 pages, 6 figure

A Bayesian Approach to Modeling Variance of Intensive Longitudinal Biomarker Data as a Predictor of Health Outcomes

Intensive longitudinal biomarker data are increasingly common in scientific studies that seek temporally granular understanding of the role of behavioral and physiological factors in relation to outcomes of interest. Intensive longitudinal biomarker data, such as those obtained from wearable devices, are often obtained at a high frequency typically resulting in several hundred to thousand observations per individual measured over minutes, hours, or days. Often in longitudinal studies, the primary focus is on relating the means of biomarker trajectories to an outcome, and the variances are treated as nuisance parameters, although they may also be informative for the outcomes. In this paper, we propose a Bayesian hierarchical model to jointly model a cross-sectional outcome and the intensive longitudinal biomarkers. To model the variability of biomarkers and deal with the high intensity of data, we develop subject-level cubic B-splines and allow the sharing of information across individuals for both the residual variability and the random effects variability. Then different levels of variability are extracted and incorporated into an outcome submodel for inferential and predictive purposes. We demonstrate the utility of the proposed model via an application involving bio-monitoring of hertz-level heart rate information from a study on social stress

Characterizing Adversarial Examples Based on Spatial Consistency Information for Semantic Segmentation

Deep Neural Networks (DNNs) have been widely applied in various recognition tasks. However, recently DNNs have been shown to be vulnerable against adversarial examples, which can mislead DNNs to make arbitrary incorrect predictions. While adversarial examples are well studied in classification tasks, other learning problems may have different properties. For instance, semantic segmentation requires additional components such as dilated convolutions and multiscale processing. In this paper, we aim to characterize adversarial examples based on spatial context information in semantic segmentation. We observe that spatial consistency information can be potentially leveraged to detect adversarial examples robustly even when a strong adaptive attacker has access to the model and detection strategies. We also show that adversarial examples based on attacks considered within the paper barely transfer among models, even though transferability is common in classification. Our observations shed new light on developing adversarial attacks and defenses to better understand the vulnerabilities of DNNs.Comment: Accepted to ECCV 201

Raptor Encoding for Low-Latency Concurrent Multi-PDU Session Transmission with Security Consideration in B5G Edge Network

In B5G edge networks, end-to-end low-latency and high-reliability transmissions between edge computing nodes and terminal devices are essential. This paper investigates the queue-aware coding scheduling transmission of randomly arriving data packets, taking into account potential eavesdroppers in edge networks. To address these concerns, we introduce SCLER, a Protocol Data Units (PDU) Raptor-encoded multi-path transmission method that overcomes the challenges of a larger attack surface in Concurrent Multipath Transfer (CMT), excessive delay due to asymmetric delay\&bandwidth, and lack of interaction among PDU session bearers. We propose a secure and reliable transmission scheme based on Raptor encoding and distribution that incorporates a queue length-aware encoding strategy. This strategy is modeled using Constrained Markov Decision Process (CMDP), and we solve the constraint optimization problem of optimal decision-making based on a threshold strategy. Numerical results indicate that SCLER effectively reduces data leakage risks while achieving the optimal balance between delay and reliability, thereby ensuring data security. Importantly, the proposed system is compatible with current mobile networks and demonstrates practical applicability

Study on multidrug resistance related genes of Salmonella isolated from food and clinical samples

ObjectiveTo investigate distribution of integron and extended-spectrum β-lactamase produced by Salmonella isolated from food and clinical samples， and explore the relationship between different drug resistance genes and multidrug resistance.MethodsPhenotype of ESBL-producing strains were confirmed by K-B method. The ESBL related drug resistance genes （blaTEM， blaSHV， blaCTX） and the mobile element integron in Salmonella were amplified by polymerase chain reaction. The amplified products of integron variable region were sequenced and the drug resistance gene cassettes were analyzed.ResultsThree hundred and nine Salmonella strains were isolated. A total of 138 Salmonella strains were isolated from food， including poultry （n=96）， raw pork （n=19） and aquatic products （n=23）. One hundred and seventy one Salmonella strains were isolated from clinical samples. The drug resistance rate of 309 Salmonella strains was 78.3%， and the multidrug resistance rate was 41.1%. The antimicrobial resistance rate of poultry was the highest. A total of 56 ESBL-producing strains were detected， of which 35 strains carried the ESBL genes （15 strains carried blaTEM； 10 strains carried blaCTX， 10 strains carried blaTEM and blaCTX ）. The blaSHV gene was not detected. A total of 98 strains which carried class I integron gene were detected， and the positive rate was 31.7%. Among the 98 strains， 54 strains carried drug resistance gene cassette. Forty seven strains carried dfrA and aadA， 1 strain carried linG-aadA22， the rest were empty gene cassette. The multi-drug resistance rates of integron positive and ESBL-producing strains were as high as 98.0% and 89.3%， respectively. The positive rate of integron in ESBL-producing strains was 76.8% （43/56）.ConclusionThe class I integron and ESBL-producing Salmonella were widely distributed in this area. The genotypes of ESBL-producing strains were mainly blaTEM and blaCTX. Both integron and ESBL-producing strains were associated with multidrug resistance. The dug resistance situation of Salmonella in this area was serious， and it was particularly necessary to pay attention to the standardized use of antibiotics in poultry breeding

Calculating and comparing codon usage values in rare disease genes highlights codon clustering with disease-and tissue- specific hierarchy

We designed a novel strategy to define codon usage bias (CUB) in 6 specific small cohorts of human genes. We calculated codon usage (CU) values in 29 non-disease-causing (NDC) and 31 disease-causing (DC) human genes which are highly expressed in 3 distinct tissues, kidney, muscle, and skin. We applied our strategy to the same selected genes annotated in 15 mammalian species. We obtained CUB hierarchical clusters for each gene cohort which showed tissue-specific and disease-specific CUB fingerprints. We showed that DC genes (especially those expressed in muscle) display a low CUB, well recognizable in codon hierarchical clustering. We defined the extremely biased codons as “zero codons” and found that their number is significantly higher in all DC genes, all tissues, and that this trend is conserved across mammals. Based on this calculation in different gene cohorts, we identified 5 codons which are more differentially used across genes and mammals, underlining that some genes have favorite synonymous codons in use. Since of the muscle genes clear clusters, and, among these, dystrophin gene surprisingly does not show any “zero codon” we adopted a novel approach to study CUB, we called “mapping-on-codons”. We positioned 2828 dystrophin missense and nonsense pathogenic variations on their respective codon, highlighting that its frequency and occurrence is not dependent on the CU values. We conclude our strategy consents to identify a hierarchical clustering of CU values in a gene cohort-specific fingerprints, with recognizable trend across mammals. In DC muscle genes also a disease-related fingerprint can be observed, allowing discrimination between DC and NDC genes. We propose that using our strategy which studies CU in specific gene cohorts, as rare disease genes, and tissue specific genes, may provide novel information about the CUB role in human and medical genetics, with implications on synonymous variations interpretation and codon optimization algorithms

African trypanosomiasis resistance in cattle by a transgenic approach

African trypanosomiasis, caused by extracellular protozoan parasites (Trypanosoma), is, a major disease in cattle that affects agricultural production in broad regions of Africa. The, parasites are transmitted between mammals by infected tsetse flies (Glossina sp.) during, blood feeding. Both wild and domestic animals are potential reservoirs of the parasites for, human infection resulting in human sleeping sickness. In order to control the disease, we, proposed a new strategy for creating resistance in cattle to African trypanosomiasis by a, transgenic approach. Using the technique of somatic cell nuclear transfer (cloning), we aim, to establish genetically modified cattle on the background of a Kenyan indigenous breed –, Kenyan Boran, which carry a gene that imparts resistance to African trypanosomes. The, gene, apoL-1, encodes the key trypanolytic component of baboon’s protective Trypanosome, Lytic Factor (TLF) against both cattle and human infective trypanosomes. TLFs are only, found in humans, gorillas, sooty mangabys, mandrills and baboons and govern resistance, to different African trypanosome species. Baboons are remarkably resistant to all African, trypanosomes due to its TLF, specifically apoL-1. Previous research with transgenic mice, has shown that the baboon apoL-1 product was able to confer protection to the mice, against trypanosome infection. Therefore, we hypothesise that expression of baboon apoL-, 1 in cattle will also endow endogenous resistance to trypanosomes. As the proof of concept, step, we have successfully set up and tested the platform for somatic cell nuclear transfer, using Boran bovine embryonic fibroblasts (BEFs). In total, two cloned calves were born by, caesarean section operation. One calf survives up to today and is in good health. Attempts, are ongoing to introduce the apoL-1 gene into two of the BEFs lines for future production, of transgenic cattle.