Nonlinear Topological Magnon Spin Hall Effect.

When a magnon passes through two-dimensional magnetic textures, it will experience a fictitious magnetic field originating from the 3×3 skew-symmetric gauge fields. To date, only one of the three independent components of the gauge fields has been found to play a role in generating the fictitious magnetic field, while the other two are perfectly hidden. In this Letter, we show that they are concealed in the nonlinear magnon transport in magnetic textures. Without loss of generality, we theoretically study the nonlinear magnon-skyrmion interaction in antiferromagnets. By analyzing the scattering features of three-magnon processes between the circularly polarized incident magnon and breathing skyrmion, we predict a giant Hall angle of both the confluence and splitting modes. Furthermore, we find that the Hall angle reverses its sign when one switches the handedness of the incident magnons. We dub this the nonlinear topological magnon spin Hall effect. Our findings are deeply rooted in the bosonic nature of magnons that the particle number is not conserved, which has no counterpart in low-energy fermionic systems and may open the door for probing gauge fields by nonlinear means.

Twisted Magnon Frequency Comb and Penrose Superradiance.

Quantization effects of the nonlinear magnon-vortex interaction in ferromagnetic nanodisks are studied. We show that the circular geometry twists the spin-wave fields with spiral phase dislocations carrying quantized orbital angular momentum (OAM). Meanwhile, the confluence and splitting scattering of twisted magnons off the gyrating vortex core (VC) generates a frequency comb consisting of discrete and equally spaced spectral lines, dubbed as twisted magnon frequency comb (TMFC). It is found that the mode spacing of the TMFC is equal to the gyration frequency of the VC and the OAM quantum numbers between adjacent spectral lines differ by one. By applying a magnetic field perpendicular to the plane of a thick nanodisk, we observe a magnonic Penrose superradiance inside the cone vortex state, which mimics the amplification of particles scattered from a rotating black hole. It is demonstrated that the higher-order modes of TMFC are significantly amplified while the lower-order ones are trapped within the VC gyrating orbit which manifests as the ergoregion. These results suggest a promising way to generate twisted magnons with large OAM and to drastically improve the flatness of the magnon comb.

[Statistical methods for relative risk estimation and applications in case-cohort study].

Objective: To systematically introduce the design of case-cohort study and the statistical methods of relative risk estimation and their application in the design. Methods: First, we introduced the basic principles of case-cohort study design. Secondly, Prentice's method, Self-Prentice method and Barlow method were described in the weighted Cox proportional hazard regression models in detail, finally, the data from the Shanghai Women's Health Study were used as an example to analyze the association between obesity and liver cancer incidence in the full cohort and case-cohort sample, and the results of parameters from each method were compared. Results: Significant association was observed between obesity and risk for liver cancer incidence in women in both the full cohort and the case-cohort sample. In the Cox proportional hazard regression model, the partial regression coefficients of the full cohort and the case-cohort sample fluctuated with the adjustment of confounding factors, but the hazard ratio estimates of them were close. There was a difference in the standard error of the partial regression coefficient between the full cohort and the case-cohort sample. The standard error of the partial regression coefficient of the case-cohort sample was larger than that of the full cohort, resulting in a wider 95% confidence interval of the relative risk. In the weighted Cox proportional hazard regression model, the standard error of the partial regression coefficient of Prentice's method was closer to the parameter estimates from full cohort than Self-Prentice method and Barlow method, and the 95% confidence interval of hazard ratio was closer to that of the full cohort. Conclusions: Case-cohort design could yield parameter results closer to the full cohort by collecting and analyzing data from sub-cohort members and patients with the disease, and reduce sample size and improve research efficiency. The results suggested that Prentice's method would be preferred in case-cohort design.

Magnonic Frequency Comb through Nonlinear Magnon-Skyrmion Scattering.

An optical frequency comb consists of a set of discrete and equally spaced frequencies and has found wide applications in the synthesis over a broad range of spectral frequencies of electromagnetic waves and precise optical frequency metrology. Despite the analogies between magnons and photons in many aspects, the analog of an optical frequency comb in magnonic systems has not been reported. Here, we theoretically study the magnon-skyrmion interaction and find that a magnonic frequency comb (MFC) can be generated above a threshold driving amplitude, where the nonlinear scattering process involving three magnons prevails. The mode spacing of the MFC is equal to the breathing-mode frequency of the skyrmion and is thus tunable by either electric or magnetic means. The theoretical prediction is verified by micromagnetic simulations, and the essential physics can be generalized to a large class of magnetic solitons. Our findings open a new pathway to observe frequency comb structures in magnonic devices that may inspire the study of fundamental nonlinear physics in spintronic platforms in the future.

[Relationship between health literacy and health-related behaviors of enterprise employees].

Objective: To explore the relationship between the health literacy of employees and smoking, drinking, diet and exercise, and provide scientific basis for health education and targeted intervention. Methods: From February to July 2019, a cluster random sampling method was adopted to select enterprise employees in Shihezi City to conduct a questionnaire survey. Self-made questionnaires and "National Resident Health Literacy Monitoring Questionnaire" were used to assess the social demographics, health literacy, and Health-related behaviors were investigated, and 1053 valid questionnaires were collected. Logistic regression model was used to analyze the relationship between health literacy and the three dimensions with smoking, drinking, diet and exercise. Results: Total score of health literacy of enterprise employees is (42.06±11.03) points and the employee health literacy rate of Shihezi City in 2019 is 19.47%. Univariate analysis showed that non-smokers had higher health literacy and three-dimensional health literacy availability than smokers (P<0.01) ; fewer drinkers had higher health literacy availability than overdrinkers (P<0.05) ; balanced diet health literacy availability The health literacy availability rates in the three dimensions were higher than those in the unbalanced diet (P<0.01) . In the logistic regression analysis, healthy lifestyle and behavioral literacy were independently related to smoking behavior (OR=1.571, P<0.05) ; the presence of health literacy and the three dimensions of health literacy were not statistically related to alcohol consumption (P>0.05) ; there is a statistical correlation between health literacy, healthy lifestyles, behaviors, and health skills and regular exercise among employees (OR=1.829、2.503、1.395, P<0.05) ; employees with health literacy and three dimensions of health literacy are more likely to have a balanced diet (P<0.01) . Conclusion: There is a correlation between the health literacy of enterprise employees and diet and exercise. The improvement of health literacy level is an important way to interfere with unhealthy behaviors.

Twisted Magnon as a Magnetic Tweezer.

Wave fields with spiral phase dislocations carrying orbital angular momentum (OAM) have been realized in many branches of physics, such as for photons, sound waves, electron beams, and neutrons. However, the OAM states of magnons (spin waves)-the building block of modern magnetism-and particularly their implications have yet to be addressed. Here, we theoretically investigate the twisted spin-wave generation and propagation in magnetic nanocylinders. The OAM nature of magnons is uncovered by showing that the spin-wave eigenmode is also the eigenstate of the OAM operator in the confined geometry. Inspired by optical tweezers, we predict an exotic "magnetic tweezer" effect by showing skyrmion gyrations under twisted magnons in the exchange-coupled nanocylinder-nanodisk heterostructure, as a practical demonstration of magnonic OAM transfer to manipulate topological spin defects. Our study paves the way for the emerging magnetic manipulations by harnessing the OAM degree of freedom of magnons.

Rapid Determination of Ammonia in Biological Samples by GC-MS Derivatization Method.

ABSTRACT: Objective To establish a qualitative and quantitative method to determine ammonia in biological samples by gas chromatography-mass spectrometry （GC-MS）. Methods A heptafluorobutyryl chloride derivatization method was used. GC-MS was used for determination. The effects of different pH conditions, derivatization temperature, time and different extraction solvents on the test results were investigated. The pretreatment conditions were optimized. Results This method could accurately detect the ammonia content in blood, and the limit of detection was determined to be 0.1 µg/mL. The target component showed good linearity in the range of 0.5-200.0 µg/mL （R2=0.987 7）. The relative standard deviation range of intra-day precision was 2.59%-3.88%. The relative standard deviation range of inter-day precision was 3.21%-3.76%. Conclusion The method showed good sensitivity, stability and specificity, therefore can be used for forensic toxicology analysis and clinical biochemical detection.

Steady Bell State Generation via Magnon-Photon Coupling.

We show that parity-time (PT) symmetry can be spontaneously broken in the recently reported energy level attraction of magnons and cavity photons. In the PT-broken phase, the magnon and photon form a high-fidelity Bell state with maximum entanglement. This entanglement is steady and robust against the perturbation of the environment, which is in contrast to the general wisdom that expects instability of the hybridized state when the symmetry is broken. This anomaly is further understood by the compete of non-Hermitian evolution and particle number conservation of the hybrid system. As a comparison, neither PT-symmetry breaking nor steady magnon-photon entanglement is observed inside the normal level repulsion case. Our results may open an exciting window to utilize magnon-photon entanglement as a resource for quantum information science.

[Research Progress on Estimation of Postmortem Submersion Interval].

ABSTRACT: Postmortem interval （PMI） estimation is one of the most important and difficult academic tasks in forensic sciences. Due to the influence of the corpse itself and the water environment, corpses in water have unique corruption phenomenon and laws. Based on the experience of traditional PMI studies of corpses on land, forensic practitioners across the world have proposed a variety of practical methods for estimating postmortem submersion interval （PMSI）. This paper summarizes the literatures related to PMSI in recent years, and introduces methods to infer PMSI according to the phenomenon of corpses, the development of insects, the succession pattern of aquatic organisms, and the changes of other physical and chemical indexes of corpses, in order to provide some reference for the study of PMSI of corpses in water.

Prediction of Attractive Level Crossing via a Dissipative Mode.

The new field of spin cavitronics focuses on the interaction between the magnon excitation of a magnetic element and the electromagnetic wave in a microwave cavity. In the strong interaction regime, such an interaction usually gives rise to the level anticrossing for the magnonic and the electromagnetic mode. Recently, the attractive level crossing has been observed, and it is explained by a non-Hermitian model Hamiltonian. However, the mechanism of such attractive coupling is still unclear. We reveal the secret by using a simple model with two harmonic oscillators coupled to a third oscillator with large dissipation. We further identify this dissipative third party as the invisible cavity mode with large leakage in cavity-magnon experiments. This understanding enables one to design dissipative coupling in all sorts of coupled systems.

Genetic association between the NLRP3 gene and acne vulgaris in a Chinese population.

BACKGROUND: Acne vulgaris is a common chronic skin disease. Inflammation is an important pathogenetic mechanism of acne, and NLRP3 polymorphisms have been reported to be involved in the mediation and occurrence of the inflammation. However, only a few studies on NLRP3 and acne have been reported, and the mechanism remains unclear. AIM: To investigate two SNPs in the NLRP3 gene in patients with acne vulgaris (AV) and healthy controls (HCs) in a Chinese population. METHODS: A case-control study was performed with 428 patients with AV and 384 (HCs). The SNPs rs10754558 and rs4612666 of the NLRP3 gene were genotyped using PCR with sequence-specific primers. A dual luciferase reporter assay was performed to determine whether the SNP rs10754558 might be responsible for the altered NLRP3 gene expression in AV by disrupting the interaction between micro-RNA (miR)-4273 and NLRP3 mRNA. Additionally, the mRNA level of NLRP3 was measured by PCR in the two groups. RESULTS: The frequencies of the G allele of rs10754558 were 0.54 in patients and 0.49 in HCs (P < 0.05). No significant difference was observed for SNP rs4612666. Dual luciferase reporter assay revealed that luciferase activity was downregulated by about 40% when the G allele of rs10754558 coexisted with miRNA-4273, indicating that the G allele might interfere with miR-4273 function and alter NLRP3 expression. The level of NLRP3 mRNA in patients with AV was significantly higher than that in HCs. CONCLUSIONS: Our study suggests that the NLRP3 SNP rs10754558 is associated with the incidence of AV. The G allele might be a genetic risk factor for AV in the Chinese population.

[Surgery of congenital heart disease: development and hopes].

People have made great progress in the surgical treatment of congenital heart disease in China, but the surgical treatment of congenital heart disease in the new era also presents some new features and trends. The data of the incidence, the constituent ratio and the change of diagnosis and treatment strategy of congenital heart disease In recent years have been analyzed to understand characteristics of congenital cardiac surgery. That will be very helpful to clarify the current status of surgical treatment of congenital heart disease in our country, formulate a more reasonable development strategy of congenital cardiac surgery, and promote the development of congenital cardiac surgery in the future.

[The reasonable use of right ventricular protection strategy in right ventricular outflow tract reconstruction].

As a result of right ventricular outflow tract reconstruction, which is the important and basic step of complex cardiac surgery, the blood flow of right ventricular outflow tract is unobstructed, while pulmonary valve regurgitation and right heart dysfunction could be happened. These problems are often ignored in early days, more and more cases of right heart dysfunction need clinical intervention, which is quite difficult and less effective. How to protect effectively the right ventricular function is the focus. At present main methods to protect the right ventricular function include trying to avoid or reduce length of right ventricular incision, reserving or rebuilding the function of the pulmonary valve, using growth potential material for surgery. The protection of the right ventricular function is a systemic project, it involves many aspects, single measures is difficult to provide complete protection, only the comprehensive use of various protection strategy, can help to improve the long-term prognosis.

Spin Hall magnetoresistance in the non-collinear ferrimagnet GdIG close to the compensation temperature.

We investigate the spin Hall magnetoresistance (SMR) in a gadolinium iron garnet (GdIG)/platinum (Pt) heterostructure by angular dependent magnetoresistance measurements. The magnetic structure of the ferromagnetic insulator GdIG is non-collinear near the compensation temperature, while it is collinear far from the compensation temperature. In the collinear regime, the SMR signal in GdIG is consistent with the usual [Formula: see text] relation well established in the collinear magnet yttrium iron garnet, with [Formula: see text] the angle between magnetization and spin Hall spin polarization direction. In the non-collinear regime, both an SMR signal with inverted sign and a more complex angular dependence with four maxima are observed within one sweep cycle. The number of maxima as well as the relative strength of different maxima depend strongly on temperature and field strength. Our results evidence a complex SMR behavior in the non-collinear magnetic regime that goes beyond the conventional formalism developed for collinear magnetic structures.

[A new perspective of survival data on clinical epidemiology: introduction of competitive risk model].

Competing risks occur frequently in the analysis of survival data that should be dealt with competing risk models. Competing risk is an event whose occurrence precludes the occurrence of the primary event of interest. Previous commonly used Kaplan-Meier method tends to overestimate the cumulative survival functions, while the traditional Cox proportional hazards model falsely evaluates the effects of covariates on the hazard related to the occurrence of the event. There are few domestic reports mentioning the concept, application and methodology of competing risk model as well as the implementation procedures or resolution of model conditions and parameters. The current work aims to explain the core concept and methodology of the competing risk model and to illustrate the process of analysis on cumulative incidence rate, using both the cause-specific hazard function model and the sub-distribution hazard function model. Software macro code in SAS 9.4 is also provided to assist clinical researchers to further understand the application of the model so to properly analyze the survival data.

Dynamic magnetic susceptibility and electrical detection of ferromagnetic resonance.

The dynamic magnetic susceptibility of magnetic materials near ferromagnetic resonance (FMR) is very important in interpreting the dc voltage obtained in its electrical detection. Based on the causality principle and the assumption that the usual microwave absorption lineshape of a homogeneous magnetic material around FMR is Lorentzian, the general forms of the dynamic magnetic susceptibility of an arbitrary sample and the corresponding dc voltage lineshapes of its electrical detection were obtained. Our main findings are as follows. (1) The dynamic magnetic susceptibility is not a Polder tensor for a material with an arbitrary magnetic anisotropy. The two off-diagonal matrix elements of the tensor near FMR are not, in general, opposite to each other. However, the linear response coefficient of the magnetization to the total radio frequency (rf) field (the sum of the external and internal rf fields due to precessing magnetization is a quantity which cannot be measured directly) is a Polder tensor. This may explain why the two off-diagonal susceptibility matrix elements were always wrongly assumed to be opposite to each other in almost all analyses. (2) The frequency dependence of dynamic magnetic susceptibility near FMR is fully characterized by six real numbers, while its field dependence is fully characterized by seven real numbers. (3) A recipe of how to determine these numbers by standard microwave absorption measurements for a sample with an arbitrary magnetic anisotropy is proposed. Our results allow one to unambiguously separate the contribution of the anisotropic magnetoresistance to the dc voltage signals from the anomalous Hall effect. With these results, one can reliably extract the information of spin pumping and the inverse spin-Hall effect, and determine the spin-Hall angle. (4) In the case that resonance frequency is not sensitive to the applied static magnetic field, the field dependence of the matrix elements of dynamic magnetic susceptibility, as well as the dc voltage, may have another non-resonance broad peak. Thus, one should be careful in interpreting the observed peaks.

[Determination of 1-methylhydantoin Concentration in Blood by GC-MS Method and Its Application in Forensic Medicine].

OBJECTIVES: To establish a gas chromatographic-mass spectrometric （GC-MS） analysis method for quantifying 1-methylhydantoin concentration in whole blood. To provide technical support to forensic identification related cases of 1-methylhydantoin. METHODS: As an internal standard, 500 ng SKF525A was added to 0.5 mL blood sample, and then 2 mL 0.01 mol/L dilute hydrochloric acid and 0.5 g ammonium carbonate were added in order to buffer the pH value to 9, and following 2 mL ethyl acetate. The organic solvent layer was obtained after centrifuge and then analysed by GC-MS after drying. RESULTS: Good linear relationship of 1-methylhydantoin in blood was obtained in the range of 0.5-50 ng/mL. The equation of linear regression was y=0.015 51 x+0.007 26（R²=0.999 7） with 0.1 ng/mL detection limit, and the recovery was 93.02%-108.12%. The intra-day and inter-day precision were less than 6.07% and 13.37%, respectively. CONCLUSIONS: The results gotten by this method is accurate and reproducible, which can be used for the determination of 1-methylhydantoin concentration in blood samples.

Association between a microRNA-214 binding site polymorphism in the methylenetetrahydrofolate reductase gene and esophageal squamous cell carcinoma.

MicroRNAs (miRNAs) are key regulators of gene expression and play an important role in the development and progression of various diseases including esophageal squamous cell carcinoma (ESCC). In this study, we determined whether a polymorphism at the miR-214 binding site in the 3'-untranslated region (3'-UTR) of the methylenetetrahydrofolate reductase gene (MTHFR) is associated with susceptibility to ESCC. A total of 448 ESCC cases and 460 gender- and age-matched subjects were recruited for the study. The genotypes of the rs114673809 single nucleotide polymorphism (SNP) were determined by polymerase chain reaction sequencing. Associations between genotypes of MTHFR rs114673809 and ESCC risk were determined using logistic regression analyses. In the recessive model, when the MTHFR rs114673809 GG homozygote genotype was used as the reference group, the GA genotype was not associated with the risk of ESCC (GA vs GG: OR = 1.261, 95%CI = 0.960-1.657, P = 0.110), but the AA genotype was associated with increased risk of ECSS (AA vs GG: OR = 1.752, 95%CI = 1.076-2.853, P = 0.027). Additionally, the rs114673809 A allele carriers also showed a 1.286-fold increased ESCC risk compared with those carrying the rs114673809 G allele genotype. Furthermore, we observed a significant increase in plasma homocysteine levels in ESCC cases carrying the AA genotype relative to ESCC cases carrying the GG genotype. Our data demonstrate that a polymorphism at the miR-214 binding site in the 3'-UTR of MTHFR is an ESCC susceptibility SNP in the Chinese population.

Skyrmion Creation and Manipulation by Nano-Second Current Pulses.

Easy creation and manipulation of skyrmions is important in skyrmion based devices for data storage and information processing. We show that a nano-second current pulse alone is capable of creating/deleting and manipulating skyrmions in a spin valve with a perpendicularly magnetized free layer and broken chiral symmetry. Interestingly, for an in-plane magnetized fixed layer, the free layer changes from a single domain at zero current to a Neel wall at an intermediate current density. Reverse the current polarity, the Neel wall changes to its image inversion. A properly designed nano-second current pulse, that tends to convert one type of Neel walls to its image inversion, ends up to create a stable skyrmion without assistance of external fields. For a perpendicularly magnetized fixed layer, the skyrmion size can be effectively tuned by a current density.