Néel Spin Currents in Antiferromagnets.

Ferromagnets are known to support spin-polarized currents that control various spin-dependent transport phenomena useful for spintronics. On the contrary, fully compensated antiferromagnets are expected to support only globally spin-neutral currents. Here, we demonstrate that these globally spin-neutral currents can represent the Néel spin currents, i.e., staggered spin currents flowing through different magnetic sublattices. The Néel spin currents emerge in antiferromagnets with strong intrasublattice coupling (hopping) and drive the spin-dependent transport phenomena such as tunneling magnetoresistance (TMR) and spin-transfer torque (STT) in antiferromagnetic tunnel junctions (AFMTJs). Using RuO_{2} and Fe_{4}GeTe_{2} as representative antiferromagnets, we predict that the Néel spin currents with a strong staggered spin polarization produce a sizable fieldlike STT capable of the deterministic switching of the Néel vector in the associated AFMTJs. Our work uncovers the previously unexplored potential of fully compensated antiferromagnets and paves a new route to realize the efficient writing and reading of information for antiferromagnetic spintronics.

Visualization of Chiral Electronic Structure and Anomalous Optical Response in a Material with Chiral Charge Density Waves.

Chiral materials have attracted significant research interests as they exhibit intriguing physical properties, such as chiral optical response, spin-momentum locking, and chiral induced spin selectivity. Recently, layered transition metal dichalcogenide 1T-TaS_{2} has been found to host a chiral charge density wave (CDW) order. Nevertheless, the physical consequences of the chiral order, for example, in electronic structures and the optical properties, are yet to be explored. Here, we report the spectroscopic visualization of an emergent chiral electronic band structure in the CDW phase, characterized by windmill-shaped Fermi surfaces. We uncover a remarkable chirality-dependent circularly polarized Raman response due to the salient in-plane chiral symmetry of CDW, although the ordinary circular dichroism vanishes. Chiral Fermi surfaces and anomalous Raman responses coincide with the CDW transition, proving their lattice origin. Our Letter paves a path to manipulate the chiral electronic and optical properties in two-dimensional materials and explore applications in polarization optics and spintronics.

[Analysis of respiratory syncytial virus detection outcomes of 973 cases with severe respiratory infection during 2016-2019, Yuhang district of Hangzhou].

This study collected nasopharyngeal swab specimens from severe respiratory infection cases in First People's Hospital of Yuhang District during 2016-2019. Real-time PCR was used to detect respiratory syncytial virus (RSV). Rate of RSV positive detection were analysised in different age groups and different months. A total of 973 nasopharyngeal swab specimens of severe respiratory infection cases were collected, and the total positive rate of nucleic acid test of RSV was 6.47%; The detection rate of nucleic acid in male is higher than that in female, with no statistical differences (P=0.023). The positive rate of nucleic acid test was negatively correlated with age. The positive rate was 15.2% in the group aged 0-1 years and 12% in the group aged 1-2 years. There are obvious seasonal differences in the prevalence of RSV, human are easier to infect RSV in spring and winter.

Temperature-Induced Lifshitz Transition and Possible Excitonic Instability in ZrSiSe.

The nodal-line semimetals have attracted immense interest due to the unique electronic structures such as the linear dispersion and the vanishing density of states as the Fermi energy approaching the nodes. Here, we report temperature-dependent transport and scanning tunneling microscopy (spectroscopy) [STM(S)] measurements on nodal-line semimetal ZrSiSe. Our experimental results and theoretical analyses consistently demonstrate that the temperature induces Lifshitz transitions at 80 and 106 K in ZrSiSe, which results in the transport anomalies at the same temperatures. More strikingly, we observe a V-shaped dip structure around Fermi energy from the STS spectrum at low temperature, which can be attributed to co-effect of the spin-orbit coupling and excitonic instability. Our observations indicate the correlation interaction may play an important role in ZrSiSe, which owns the quasi-two-dimensional electronic structures.

[Inhibitors of RAS Might Be a Good Choice for the Therapy of COVID-19 Pneumonia].

The novel coronavirus 2019 (COVID-19) infected patients by binding human ACE2, leading to severe pneumonia and highly mortality rate in patients. At present, there is no definite and effective treatment for COVID-19. ACE2 plays an important role in the RAS, and the imbalance between ACE/Ang II/AT1R pathway and ACE2/Ang (1-7)/Mas receptor pathway in the RAS system will lead to multi-system inflammation. Increased ACE and Ang II are poor prognostic factors for severe pneumonia. Animal studies have shown that RAS inhibitors could effectively relieve symptoms of acute severe pneumonia and respiratory failure. The binding of COVID-19 and ACE2 resulted in the exhaustion of ACE2, and then ACE2/Ang (1-7)/Mas receptor pathway was inhibited. The balance of the RAS system was broken, and this would lead to the exacerbation of acute severe pneumonia. Therefore, we speculate that ACEI and AT1R inhibitors could be used in patients with COVID-19 pneumonia under the condition of controlling blood pressure, and might reduce the pulmonary inflammatory response and mortality.

[Inhibitors of RAS Might Be a Good Choice for the Therapy of COVID-19 Pneumonia].

The novel coronavirus 2019 (COVID-19) infected patients by binding human ACE2, leading to severe pneumonia and highly mortality rate in patients. At present, there is no definite and effective treatment for COVID-19. ACE2 plays an important role in the RAS, and the imbalance between ACE/Ang II/AT1R pathway and ACE2/Ang (1-7)/Mas receptor pathway in the RAS system will lead to multi-system inflammation. Increased ACE and Ang II are poor prognostic factors for severe pneumonia. Animal studies have shown that RAS inhibitors could effectively relieve symptoms of acute severe pneumonia and respiratory failure. The binding of COVID-19 and ACE2 resulted in the exhaustion of ACE2, and then ACE2/Ang (1-7)/Mas receptor pathway was inhibited. The balance of the RAS system was broken, and this would lead to the exacerbation of acute severe pneumonia. Therefore, we speculate that ACEI and AT1R inhibitors could be used in patients with COVID-19 pneumonia under the condition of controlling blood pressure, and might reduce the pulmonary inflammatory response and mortality.

[Correlation between intestinal mucosal permeability and prognosis in patients with liver cirrhosis].

Objective: To investigate the correlation between changes in intestinal mucosal permeability and prognosis of patients with liver cirrhosis. Methods: Data of 89 cases with liver cirrhosis who were hospitalized in the Hepatology Department of Shanxi Provincial Hospital of Traditional Chinese Medicine from January 2017 to August 2017 were collected as the liver cirrhosis experimental group, and 40 healthy subjects were randomly selected as the healthy control group. JY-DLT, the Intestinal Mucosal Barrier Biochemical Index Analysis System was used to measure the levels of serum diamine oxidase (DAO), D-lactic acid, and endotoxin (ETX) in two groups to evaluate intestinal mucosal barrier function. Spearman's rank correlation test was used to evaluate the correlation between liver cirrhosis prognosis and intestinal mucosal permeability. The results of the two groups were compared by Mann-Whitney H test of two independent samples. One-way Anova was used for intergroup comparison. The pairwise comparison between groups was performed using the LSD or SNK test. Results: The level of ETX in patients with decompensated cirrhosis was significantly higher than that in the compensated phase, and the difference was statistically significant (P < 0.05). The levels of DAO, D-lactic acid and ETX in the liver cirrhosis group were significantly higher than those in the healthy control group, and the differences were statistically significant (P < 0.01). The plasma levels of DAO, D-lactic acid and ETX in the Child-Pugh grade groups of patients with liver cirrhosis were significantly higher than those in the healthy control group, and the differences were statistically significant (P < 0.05). The results of intergroup comparison showed that there were statistically significant differences in DAO, D-lactic acid and ETX levels between Child-Pugh grade A and grade B groups (t = -4.255, 2.527, -2.179, P < 0.05). Furthermore, there were statistically significant differences in the levels of D-lactic acid and ETX between the Child-Pugh grade A and grade C groups (t = -2.693, -4.248, P < 0.01).The plasma levels of DAO, D-lactic acid and ETX levels were positively correlated (r = 0.205, 0.372, 0.342, P < 0.01). D-lactic acid and ETX levels were positively correlated with CTP score, Forns' index, RPR index, APRI score, FIB-4 index and FibroScan score(P < 0.01). Conclusion: The three indices (plasma DAO, D-lactic acid, and ETX) can accurately detect the changes in intestinal mucosal permeability. Moreover, the higher index of intestinal mucosal permeability causes the more severe degree of liver cirrhosis and the correlation between the intestinal mucosal permeability and the prognosis score of liver cirrhosis provides a reference for a new evaluation system and new ideas for the treatment of liver cirrhosis.

[Clinical-pathological analysis of 71 cases of dermatosis papulosa nigra of Han Chinese people].

Objective: To analyze and summarize the clinical-pathological features of dermatosis papulosa nigra of Han Chinese people. Methods: We collected 71 cases of dermatosis papulosa nigra in the Third people's Hospital of Hangzhou Affiliated to Zhejiang Chinese Medical University of Department of Dermatology from January 2010 to January 2019 which were confirmed clinically and pathologically. The clinical and histopathological data of all patients were analyzed and summarized, and relevant literature were reviewed. Results: Among the 71 patients, 51 were female and 25 were male, their average age was (44±13) years, the average age of onset was (39±14) years, and the average time of diagnosis was (65±51) months. The lesions were multiple dark brown papules with smooth surface, and mostly distributed in the chest and abdomen, 46 cases (64.8%), followed by the back and neck. The mean diameter of the lesions was (1.76±0.99) mm. Meanwhile, the initial onset of pruritus was observed in 15 patients. The pathological features of all lesions were similar to seborrheic keratosis. According to pathological classification, there were 49 (69.0%) cases of the acanthotic type, 11(15.5%) cases of the hyperkeratotic type, 6 (8.5%) cases of spiroid type, 4 (5.6%) cases of irritated type, and 1 (1.4%) case of clonal type. Epidermal pigmentation and/or dermal papillary pigmented granules were observed in 56 cases (78.9%), of which 46 cases (64.8%) had basal layer pigmentation. In addition, inflammatory cell infiltration was found in the superficial dermis of lesions of 10 patients (14.1%) with symptom of itching. Conclusion: Dermatosis papulosa nigra of Han Chinese people has some unique clinical and pathological features.

The influence of male age on treatment outcomes and neonatal birthweight following assisted reproduction technology involving intracytoplasmic sperm injection (ICSI) cycles.

The aim of this study was to investigate the effect of male age on treatment outcomes and neonatal birthweight following intracytoplasmic sperm injection (ICSI). This study included 2,474 ICSI cycles. Male partners were stratified into 5-year age categories (up to 25, 26-30, 31-35, 36-40 and 41 and up). Multilevel logistic regression was used to evaluate the relationship between male age and treatment outcomes. After adjusting for confounders, we found no difference in the clinical pregnancy rate. However, we observed that the 31- to 35-year group had a higher odds of live birth than that of the >41-year group (aOR 1.63, p = .03), and that the risk of abortion in the 31- to 35-year group was lower than that of the reference group (aOR 0.41, p = .02). A total of 754 single-foetus newborns and 556 twin newborns were analysed. Among the singletons, none of the variables differed among the five groups (p > .05). Among the twins, the infants in the 36- to 40-year group had a lower neonatal birthweight and a higher low-birthweight rate than those of the other groups (p < .05). Our study indicates that increased paternal age negatively affects the live birth and miscarriage rates. In addition, advanced paternal age may affect the birthweight of twins.

Application of miniSTR Loci and Its Detection System for Degraded Materials in Forensic Medicine.

OBJECTIVES: To establish multiplex system of 16 miniSTR loci, and explore its application value for the degraded materials in forensic medicine. METHODS: The multiplex system of 16 miniSTR loci was established using a six-dye fluorescence labeling technology and its application value in forensic medicine was assessed. RESULTS: A six-dye fluorescence labeling miniSTR amplification kit was developed, which enabled 15 autosomal STR loci, Amelogenin locus and DYS391 to be typed simultaneously. This method showed good specificity and could provide stable and accurate typing results with a sensitivity of 50 pg. This system also provided a good test result for the normal biological sample of actual cases. CONCLUSIONS: The multiplex system of 16 miniSTR loci has application value for degraded and trace materials with the advantages of high sensitivity and database compatibility, which can be used for forensic casework.

Large Positive Thermal Expansion and Small Band Gap in Double-ReO3-Type Compound NaSbF6.

Double-ReO3-type structure compound NaSbF6 undergoes a low-temperature rhombohedral to high-temperature cubic phase between 303 and 323 K, as revealed by temperature-dependent X-ray diffractions. Although many double-ReO3-type fluorides exhibit either low thermal expansion or negative thermal expansion (NTE), NaSbF6 exhibits positive thermal expansion (PTE) with a large volumetric coefficient of thermal expansion, αv = 62 ppm/K, in its cubic phase. Raman spectroscopy reveals that the low-frequency transverse vibration of fluorine atoms is stiffened in NaSbF6, compared with the typical NTE compound CaZrF6 with the same structure. The related weak contraction associated with the polyhedral rocking would be overcome by the notable elongation of the Na-F bond length on heating, thus leading to the large volumetric PTE. Unlike ScF3 and CaZrF6 which are insulators with a wide band gap, a relative small band gap of 3.76 eV was observed in NaSbF6. The small band gap can be attributed to the hybridization between the Sb 5s and F 2p orbitals.

Critical behavior in tetragonal antiperovskite GeNFe3 with a frustrated ferromagnetic state.

Tetragonal GeNFe3 has a second-order ferromagnetic (FM) to paramagnetic transition at 76 K. Our integrated investigations indicate that the ground FM state is frustrated and the tetragonal symmetry is retained below 550 K based on the results of variable temperature X-ray diffraction. Critical behavior was analyzed by a systematic bulk magnetization study. The estimated critical exponents by three different methods (modified Arrott plot, the Kouvel-Fisher method, and critical isotherm analysis) conformably suggest that long-range magnetic coupling described by mean-field (MF) theoretical model is dominant in GeNFe3. The experimental M-T-H data collapse into two independent branches according to the scaling equations m = f±(h) with the renormalized magnetization m = ε-ßM(H, ε) and the magnetic field h = Hε-(ß+γ). The exchange distance is estimated as J(r) ∼ r-4.8 on the basis of the ß and γ values, which lies between the long-range MF model (r-4.5) and the short-range 3D Heisenberg (3DH) model (r-5). Our results indicate that the competition between local magnetic moments of iron 3d electronic state and itinerant covalent interactions of N-Fe bonds should be responsible for critical behavior in this system.

Correlation between Y chromosome microdeletion and male infertility.

Dyszoospermia due to genetic factors is the leading cause of male infertility. To explore the correlation between azoospermia factor (AZF) microdeletion of the Y chromosome and male infertility, we evaluated AZF microdeletion on the long arm of the Y chromosome in 166 infertile males and 50 fertile males using multiplex polymerase chain reactions amplification and gel electrophoresis. The results demonstrated that 28 individuals had varying degrees of microdeletion in the AZF region (16.90%); 12 out of the 76 males with azoospermia and 16 out of the 90 males with oligospermia had AZF microdeletion. AZF microdeletion was not observed in any of the healthy controls. In addition, 53.60% of the AZF microdeletions occurred in the AZFc region. It can be concluded that AZF microdeletion on the long arm of the Y chromosome can result in male spermatogenesis dysfunction. Detection of AZF microdeletion can provide a theoretical basis for genetic counseling, as well as improve the diagnosis and treatment of this disease.

Vitamin D receptor FokI gene polymorphism and tuberculosis susceptibility: a meta-analysis.

Numerous studies have evaluated the association between FokI polymorphisms in the vitamin D receptor (VDR) gene and tuberculosis risk. However, the specific association remains controversial. In this study, we performed a meta-analysis to assess the association between the VDR gene FokI polymorphism and tuberculosis. Published studies from the PubMed and Embase databases were retrieved. The pooled odds ratio (OR) with 95% confidence interval (CI) was calculated using fixed- or random-effect models. Overall, a significant association was found between FokI polymorphism and tuberculosis risk when all studies were pooled (ff vs FF: OR = 1.36, 95%CI = 1.11-1.66; ff vs Ff: OR = 1.38, 95%CI = 1.14-1.67; dominant model: OR = 0.73, 95%CI = 0.61-0.88). In subgroup analysis by race, a significant association between FokI polymorphism and tuberculosis risk was observed in Asians (ff vs FF: OR = 1.71, 95%CI = 1.02-2.85; ff vs Ff: OR = 1.86, 95%CI = 1.40-2.47; dominant model: OR = 0.55, 95%CI = 0.42-0.72), and no significant association was observed among Caucasians and Africans. In conclusion, the FokI polymorphism in the VDR gene may be related to an increased risk of tuberculosis in Asians. Further large and well-designed studies are needed to confirm these conclusions.

Chemically tailoring coal to fluorescent carbon dots with tuned size and their capacity for Cu(II) detection.

The desired control of size, structure, and optical properties of fluorescent carbon dots (CDs) is critical for understanding the fluorescence mechanism and exploring their potential application. Herein, a top-down strategy to chemically tailor the inexpensive coal to fluorescent CDs by a combined method of carbonization and acidic oxidation etching is reported. The size and optical properties of the as-made CDs are tuned by controlling the structures of graphitic crystallites in the starting precursor. The coal-derived CDs exhibit two different distinctive emission modes, where the intensity of the short-wavelength emission is significantly enhanced by partial reduction treatment. The evolution of the electronic structure and the surface states analysis show that two different types of fluorescence centers, nano-sized sp(2) carbon domains and surface defects, are responsible for the observed emission characteristics. The reduced CDs are demonstrated as an effective fluorescent sensing material for label-free and selective detection of Cu(II) ions with a detection limit as low as 2.0 nM, showing a great promise for real-world sensor applications.

Development of a real-time impedance matching system for ion cyclotron resonance heating in experimental advanced superconducting tokamak.

To achieve stable operation of an ion cyclotron resonance heating (ICRH) system in the Experimental Advanced Superconducting Tokamak (EAST), a real-time impedance matching system needs to be established to respond to antenna load variation during long pulse discharges. A new impedance matching method based on capacitors was proposed in this study. By considering the reflected voltage of the transmission line as the feedback parameter, the real-time impedance-matching system can quickly control the motors based on a programmable logic controller to determine the minimum reflection voltage. A real-time impedance matching system was successfully used on the test platform in the laboratory and on the ICRH system in EAST. A significant result is that we can match the variable impedance within 1 s by suitably adjusting the motor controller to ensure high-power and long-pulse operation of the ICRH system to satisfy the requirements of the EAST experiment.

Artificial superconducting Kondo lattice in a van der Waals heterostructure.

Engineering Kondo lattice with tailored functionality is desirable for elucidating the heavy fermion physics. We realize the construction of an artificial Kondo lattice/superconductor heterojunction by growing monolayer VSe2 on bulk 2H-NbSe2 with molecular beam epitaxy. Spectroscopic imaging scanning tunneling microscopy measurements show the emergence of a new charge density wave (CDW) phase with 3 × 3 periodicity on the monolayer VSe2. Unexpectedly, a pronounced Kondo resonance appears around the Fermi level, and distributes uniformly over the entire film, evidencing the formation of Kondo lattice. Density functional theory calculations suggest the existence of magnetic interstitial V atoms in VSe2/NbSe2, which play a key role in forming the CDW phase along with the Kondo lattice observed in VSe2. The Kondo origin is verified from both the magnetic field and temperature dependences of the resonance peak, yielding a Kondo temperature of ~ 44 K. Moreover, a superconducting proximity gap opens on monolayer VSe2, whose shape deviates from the function of one-band BCS superconductor, but is reproduced by model calculations with heavy electrons participating the pairing condensate. Our work lays the experimental foundation for studying interactions between the heavy fermion liquids and the superconducting condensate.

Interference between resonant and nonresonant inelastic x-ray scattering.

A detailed study of inelastic x-ray scattering from the ground state to the 3Σg(3σ(g)(-1)3s(g)1) state of the O2 molecule is presented. The observed angular anisotropy shows that the vibrational excitations within this final state are strongly dependent on the polarization of the incident radiation. The analysis demonstrates that this is a manifestation of interference between resonant and direct nonresonant inelastic x-ray scattering. This interference provides a new tool to monitor nuclear dynamics by relative rotation of the polarization vectors of the incident and scattered photons.

Effects of early-cleavage embryo transfer on in vitro fertilization-embryo transfer pregnancy outcomes.

PURPOSE: To observe the effects of early-cleavage embryo transfer (ET) on pregnancy outcomes in vitro fertilization-embryo transfer (IVF-ET). MATERIALS AND METHODS: The data of 6,548 two pro-nucleate (2PN) embryos and 968 patients who underwent IVF or intracytoplasmic sperm injection (ICSI) were analyzed. Of the 968 cycles, early-cleavage embryos were used in 432 cycles (early-cleavage group), late-cleavage embryos were used in 246 cycles (late-cleavage group), and both early and late-cleavage embryos were used in 290 cycles (mixed group). RESULTS: High-quality embryo rate was significantly higher in early-cleavage group than in late-cleavage group (82.74% vs 59.83%; p < 0.01). Both clinical pregnancy and implantation rates in IVF or ICSI were significantly higher in early-cleavage group than in late-cleavage group (all p < 0.01). In ICSI, both clinical pregnancy and implantation rates were significantly higher in mixed group than in late-cleavage group (all p < 0.05). CONCLUSION: Early-cleavage ET can improve pregnancy outcomes in IVF or ICSI.