[Analysis of influenza vaccination status and immunization strategy in high-risk population]

Influenza is a contagious respiratory disease caused by influenza viruses, and the burden of severe disease is commonly seen in high risk populations. Influenza vaccination is an effective way to prevent influenza and its complications, especially for high risk populations. Although some countries have included influenza vaccine in their national immunization programs, influenza vaccination rates remain low globally in high risk populations. The influenza vaccine in China is still a non-immunization program vaccine that is voluntarily vaccinated at its own expense, and the influenza vaccine immunization strategy is different across the country. There is still a gap between the vaccination rate of the influenza vaccine and that of developed countries. It is an urgent problem to further optimize the whole population immunization strategy of influenza vaccine in China, strengthen the publicity of the whole population immunization strategy of influenza vaccine, and reduce the disease burden of influenza in China.

FAK-p38 signaling serves as a potential target for reverting matrix stiffness-modulated liver sinusoidal endothelial cell defenestration

Liver sinusoidal endothelial cells (LSECs) are highly specific endothelial cells which play an essential role in the maintenance of liver homeostasis. During the progression of liver fibrosis, matrix stiffening promotes LSEC defenestration, however, the underlying mechanotransduction mechanism remains poorly understood. Here, we applied stiffness-tunable hydrogels to assess the matrix stiffening-induced phenotypic changes in primary mouse LSECs. Results indicated that increased stiffness promoted LSEC defenestration through cytoskeletal reorganization. LSECs sensed the increased matrix stiffness via focal adhesion kinase (FAK), leading to the activation of p38-mitogen activated protein kinase activated protein kinase 2 (MK2) pathway, thereby inducing actin remodeling via LIM Kinase 1 (LIMK1) and Cofilin. Interestingly, inhibition of FAK or p38-MK2 pathway was able to effectively restore the fenestrae to a certain degree in LSECs isolated from early to late stages of liver fibrosis mice. Thus, this study highlights the impact of mechanotransduction in LSEC defenestration, and provides novel insights for potential therapeutic interventions for liver fibrosis.

Highly Energy-Efficient Spin Current Generation in SrIrO3 by Manipulating the Octahedral Rotation

Materials with strong spin-orbit coupling (SOC) have been continuously attracting intensive attention due to their promising application in energy-efficient, high-density, and nonvolatile spintronic devices. Particularly, transition-metal perovskite oxides with strong SOC have been demonstrated to exhibit efficient charge-spin interconversion. In this study, we systematically investigated the impact of epitaxial strain on the spin-orbit torque (SOT) efficiency in the SrIrO3(SIO)/Ni81Fe19(Py) bilayer. The results reveal that the SOT efficiency is strongly related to the octahedral rotation around the in-plane axes of the single-crystal SIO. By modulating the epitaxial strain using different substrates, the SOT efficiency can be remarkably improved from 0.15 to 1.45. This 10-fold enhancement of SOT efficiency suggests that modulating the epitaxial strain is an efficient approach to control the SOT efficiency in complex oxide-based heterostructures. Our work may have the potential to advance the application of complex oxides in energy-efficient spintronic devices.

Direct mechanical exposure initiates hepatocyte proliferation

Background & Aims

Liver paracrine signaling from liver sinusoid endothelial cells to hepatocytes in response to mechanical stimuli is crucial in highly coordinated liver regeneration. Interstitial flow through the fenestrated endothelium inside the space of Disse potentiates the role of direct exposure of hepatocytes to fluid flow in the immediate regenerative responses after partial hepatectomy, but the underlying mechanisms remain unclear.

Methods

Mouse liver perfusion was used to identify the effects of interstitial flow on hepatocyte proliferation ex vivo. Isolated hepatocytes were further exposed to varied shear stresses directly in vitro. Knockdown and/or inhibition of mechanosensitive proteins were used to unravel the signaling pathways responsible for cell proliferation.

Results

An increased interstitial flow was visualized and hepatocytes' regenerative response was demonstrated experimentally by ex vivo perfusion of mouse livers. In vitro measurements also showed that fluid flow initiated hepatocyte proliferation in a duration- and amplitude-dependent manner. Mechanistically, flow enhanced β1 integrin expression and nuclear translocation of YAP (yes-associated protein), via the Hippo pathway, to stimulate hepatocytes to re-enter the cell cycle.

Conclusions

Hepatocyte proliferation was initiated after direct exposure to interstitial flow ex vivo or shear stress in vitro, which provides new insights into the contributions of mechanical forces to liver regeneration.

Impact and implications

By using both ex vivo liver perfusion and in vitro flow exposure tests, we identified the roles of interstitial flow in the space of Disse in stimulating hepatocytes to re-enter the cell cycle. We found an increase in shear flow-induced hepatocyte proliferation via β1 integrin-YAP mechanotransductive pathways. This serves as a useful model to potentiate hepatocyte expansion in vitro using mechanical forces.

[Analysis of China's influenza vaccination policy based on the model of "behavioural and social drivers of vaccination"]

This article uses the "behavioural and social drivers of vaccination" model released by the World Health Organization (WHO) in 2022 to analyze influenza vaccine policy documents issued by the state and governments. This indicates that the current influenza vaccination policy in China has paid some attention to "publicity and mobilization", but it still pays insufficient attention to "vaccination convenience". It is recommended to continue to strengthen publicity and mobilization, explore ways to improve the convenience of vaccination, formulate corresponding plans to improve the convenience of vaccination, scientifically set vaccination rate targets, and encourage areas with conditions to carry out free vaccination projects for key populations.

Analysis of the value of echocardiographic parameters in the early diagnosis of preterm infants with bronchopulmonary dysplasia

OBJECTIVE

The objective of this study was to investigate the role of echocardiographic parameters in diagnosing bronchopulmonary dysplasia (BPD) in preterm infants.

PATIENTS AND METHODS

Ninety preterm infants with a gestational age of less than 32 weeks and a weight less than 1.5 kg, admitted to the neonatal intensive care unit of the hospital between January 2020 and January 2021, were selected for the study. The study subjects were divided into two groups: a BPD group (54 cases, observation group) and a non-BPD group (36 cases, control group). The correlation between tricuspid regurgitation (TR) velocity and BPD was investigated by detecting the cardiac function of preterm infants in both groups using a color Doppler ultrasound diagnostic instrument and analyzing the cardiac ultrasound results. The early prediction efficiency of TR velocity (m/s) for BPD was evaluated using the receiver operator characteristic (ROC) curve.

RESULTS

The incidence of patent ductus arteriosus (PDA) and pulmonary hypertension (PH) in the observation group was significantly higher than that in the control group. The levels of left ventricular ejection fraction (LVEF) and left ventricular shorting fraction (LVFS) were significantly lower than those in the control group (p < 0.05). The incidence of patent foramen ovale (PFO), atrial septal defect (ASD), and ventricular septal defect (VSD) in the observation group were not significantly different from the control group (p > 0.05). The proportion of tricuspid regurgitation in the observation group was significantly higher than that in the control group, and the TR velocity was significantly higher than that in the control group. The Spearman correlation analysis showed that TR velocity (m/s) was positively correlated to BPD severity (r = 0.379, p < 0.05). The area under the curve (AUC) for predicting BPD with TR velocity was 0.735. The sensitivity and specificity were 88.0% and 62.6%, respectively, when the TR velocity was 1.45 m/s.

CONCLUSIONS

Echocardiography is useful for understanding the degree of impaired cardiac function in preterm infants and for early detection of PH, which may reduce the mortality rate to a certain extent. The risk of BPD is significantly increased when TR velocity is higher than 1.45 m/s.

[Adult vaccination immunization strategies and research progress worldwide]

Vaccination is the most cost-effective measure to prevent infectious diseases in both children and adults. At present, the global burden of infectious diseases in adults is still heavy. With the continuous development and improvement of vaccines, vaccination has shown great potential to prevent infectious diseases, further reduce the morbidity and mortality of infectious diseases in adults and improve people's life quality. This article summarizes the current status of adult immunization, immunization strategies of representative countries, different adult vaccination strategies, and the advantages and challenges of adult immunization to provide reference for further exploring adult immunization strategies and improving adult vaccination recommendations. More attention should be paid to the immunization strategies for different adult populations, and effective measures should be taken to improve the vaccination coverage for the better protection of people's life and health.

Fetal growth trajectories of small/large for gestational age infants in twin pregnancies

BACKGROUND

Birthweight is the most common and accessible parameter in assessing neonatal perinatal outcomes and in evaluating the intrauterine environment globally. Infants born too large or too small not only may alter the maternal mode of delivery but also may face other long-term disorders, such as metabolic diseases and neurodevelopmental delay. Studies have revealed different growth profiles of large-for-gestational-age and small-for-gestational-age fetuses in singleton pregnancies. However, currently, no research is focused on the growth trajectories of these infants during twin pregnancies, even though they are at a much higher risk of being small for gestational age.

OBJECTIVE

This study aimed to explore fetal growth trajectories of large-for-gestational-age and small-for-gestational-age infants in twin pregnancies to provide strategies for fetal growth management.

STUDY DESIGN

This was a case-control study of all noncomplicated twin pregnancies delivered after 36 weeks of gestation at the Peking University First Hospital between 2012 and 2021. Ultrasound data were recorded every 2 to 4 weeks until delivery. All the infants were divided into large-for-gestational-age, small-for-gestational-age, and appropriate-for-gestational-age groups. Longitudinal fetal growth (estimated fetal weight, abdominal circumference, etc.) was compared among the 3 groups using a linear mixed model, and other maternal and neonatal perinatal outcomes were compared. Receiver operating characteristic curves were used to explore optimal biometric parameters and gestational weeks for predicting small-for-gestational-age infants.

RESULTS

Here, 797 pregnant patients with 1494 infants were recruited, with 59 small-for-gestational-age infants, 1335 appropriate-for-gestational-age infants, and 200 large-for-gestational-age infants. The mean birthweights were 1985.34±28.34 g in small-for-gestational-age infants, 2662.08±6.60 g in appropriate-for-gestational-age infants, and 3231.24±11.04 g in large-for-gestational-age infants. The estimated fetal weight of the 3 groups differed from each other from week 26, with the small-for-gestational-age fetuses weighing 51.946 g less and the large-for-gestational-age fetuses weighing 35.233 g more than the appropriate-for-gestational-age fetuses. This difference increased with gestation; at 39 weeks, the small-for-gestational-age fetuses weighed 707.438 g less and the large-for-gestational-age fetuses weighed 614.182 g more than the appropriate-for-gestational-age fetuses (all P<.05). The small-for-gestational-age group had a significantly higher rate of hospitalization (89.9 %) and jaundice (40.7 %) than the appropriate-for-gestational-age group, whereas the hospitalization rate in the large-for-gestational-age group was significantly lower than the appropriate-for-gestational-age group (7.5% and 2.5%; all P<.05). The fetal weight of the small-for-gestational-age infants with adverse outcomes remained near the 10th percentile of the reference and fell below the 3rd percentile at 34 weeks of gestation. The estimated fetal weight after 30 weeks of gestation had a satisfactory diagnostic value in predicting small-for-gestational-age infants. At 30, 32, 34, and 36 weeks of gestation, the areas under the curve were 0.829, 0.840, 0.929, and 0.889 respectively.

CONCLUSION

The growth patterns of small-for-gestational-age, appropriate-for-gestational-age, and large-for-gestational-age twin fetuses diverged from 26 weeks of gestation and continued to increase until delivery; therefore, closer monitoring is suggested from 26 weeks of gestation for those carrying small fetuses.

Artificially controlled nanoscale chemical reduction in VO2 through electron beam illumination

Chemical reduction in oxides plays a crucial role in engineering the material properties through structural transformation and electron filling. Controlling the reduction at nanoscale forms a promising pathway to harvest functionalities, which however is of great challenge for conventional methods (e.g., thermal treatment and chemical reaction). Here, we demonstrate a convenient pathway to achieve nanoscale chemical reduction for vanadium dioxide through the electron-beam illumination. The electron beam induces both surface oxygen desorption through radiolytic process and positively charged background through secondary electrons, which contribute cooperatively to facilitate the vacancy migration from the surface toward the sample bulk. Consequently, the VO₂ transforms into a reduced V₂O₃ phase, which is associated with a distinct insulator to metal transition at room temperature. Furthermore, this process shows an interesting facet-dependence with the pronounced transformation observed for the c-facet VO₂ as compared with the a-facet, which is attributed to the intrinsically different oxygen vacancy formation energy between these facets. Remarkably, we readily achieve a lateral resolution of tens nanometer for the controlled structural transformation with a commercial scanning electron microscope. This work provides a feasible strategy to manipulate the nanoscale chemical reduction in complex oxides for exploiting functionalities.

Biomechanics in liver regeneration after partial hepatectomy

The liver is a complicated organ within the body that performs wide-ranging and vital functions and also has a unique regenerative capacity after hepatic tissue injury and cell loss. Liver regeneration from acute injury is always beneficial and has been extensively studied. Experimental models including partial hepatectomy (PHx) reveal that extracellular and intracellular signaling pathways can help the liver recover to its equivalent size and weight prior to an injury. In this process, mechanical cues possess immediate and drastic changes in liver regeneration after PHx and also serve as main triggering factors and significant driving forces. This review summarized the biomechanics progress in liver regeneration after PHx, mainly focusing on PHx-based hemodynamics changes in liver regeneration and the decoupling of mechanical forces in hepatic sinusoids including shear stress, mechanical stretch, blood pressure, and tissue stiffness. Also discussed were the potential mechanosensors, mechanotransductive pathways, and mechanocrine responses under varied mechanical loading in vitro. Further elucidating these mechanical concepts in liver regeneration helps establish a comprehensive understanding of the biochemical factors and mechanical cues in this process. Proper adjustment of mechanical loading within the liver might preserve and restore liver functions in clinical settings, serving as an effective therapy for liver injury and diseases.

Trail Formation Alleviates Excessive Adhesion and Maintains Efficient Neutrophil Migration

Migrating neutrophils are found to leave behind subcellular trails in vivo, but the underlying mechanisms remain unclear. Here, an in vitro cell migration test plus an in vivo observation was applied to monitor neutrophil migration on intercellular cell adhesion molecule-1 (ICAM-1) presenting surfaces. Results indicated that migrating neutrophils left behind long-lasting, chemokine-containing trails. Trail formation tended to alleviate excessive cell adhesion enhanced by the trans-binding antibody and maintain efficient cell migration, which was associated with differential instantaneous edge velocity between the cell front and rear. CD11a and CD11b worked differently in inducing trail formation with polarized distributions on the cell body and uropod. Trail release at the cell rear was attributed to membrane ripping, in which β2-integrin was disrupted from the cell membrane through myosin-mediated rear contraction and integrin-cytoskeleton dissociation, potentiating a specialized strategy of integrin loss and cell deadhesion to maintain efficient migration. Moreover, neutrophil trails left on the substrate served as immune forerunners to recruit dendritic cells. These results provided an insight in elucidating the mechanisms of neutrophil trail formation and deciphering the roles of trail formation in efficient neutrophil migration.

Potential Roles of YAP/TAZ Mechanotransduction in Spaceflight-Induced Liver Dysfunction

Microgravity exposure during spaceflight causes the disordered regulation of liver function, presenting a specialized mechano-biological coupling process. While YAP/TAZ serves as a typical mechanosensitive pathway involved in hepatocyte metabolism, it remains unclear whether and how it is correlated with microgravity-induced liver dysfunction. Here, we discussed liver function alterations induced by spaceflight or simulated effects of microgravity on Earth. The roles of YAP/TAZ serving as a potential bridge in connecting liver metabolism with microgravity were specifically summarized. Existing evidence indicated that YAP/TAZ target gene expressions were affected by mechanotransductive pathways and phase separation, reasonably speculating that microgravity might regulate YAP/TAZ activation by disrupting these pathways via cytoskeletal remodeling or nuclear deformation, or disturbing condensates formation via diffusion limit, and then breaking liver homeostasis.

[Research progress of influenza vaccination, pneumococcal vaccination and COVID-19 vaccination among cancer patients]

This article reviews the relevant studies on the efficacy and safety of influenza, pneumococcal and COVID-19 vaccination among tumor patients worldwide in recent years. By combing and analyzing the retrieved literature, the results show that influenza and pneumococcal vaccination can significantly reduce the morbidity and hospitalization rate of infectious diseases in tumor patients, reduce the risk of cardiovascular events and death, and significantly improve survival prognosis. COVID-19 vaccination can also protect tumor patients, especially those who have completed full dose vaccination. Authoritative guidelines and consensuses worldwide all recommend that tumor patients receive influenza, pneumococcal and COVID-19 vaccines. We should carry out relevant researches, as well as take effective measures to strengthen patient education, so that tumor patients can fully experience the health protection brought by the vaccine to this specific group.

[The effect of pregnant rats exposed to radio frequency electromagnetic field on the hippocampal morphology and nerve growth factor of offspring rats]

Objective: To explore the effects of exposure of pregnant rats to radio frequency electromagnetic field on the ultrastructure of hippocampus and the levels of obesity related protein (FTO) and nerve growth factor (NGF) in offspring rats. Methods: In September 2019, 36 healthy 7-week-old Wistar rats were selected, including 24 female rats (150-200 g) and 12 male rats (200-250 g) . The male and female mice were mated in the cage at 2: 1 ratio at 18: 00 every night. The smear results showed that the sperm was positive and the mating was successful. The day was regarded as the 0 day of pregnancy. Pregnant rats were randomly divided into 3 experimental groups and 3 control groups, with 4 rats in each group. The experimental group was exposed to 1 800 MHz, Wi-Fi and 1 800 MHz+Wi-Fi respectively, and the three control groups were exposed to virtual exposure. 12 hours a day for 21 days in three batches. After the end of exposure, the offspring of each group were raised for 7 weeks. The ultrastructural changes of the hippocampus were observed by transmission electron microscopy, the FTO level in the hippocampus was determined by Western blot, and the NGF level in the brain tissue was determined by ELISA. Results: Transmission electron microscopy showed that the nuclei of hippocampal tissue of female and male rats in the 1800 MHz group were slightly contracted, the cytoplasm was slightly edema, and the nuclei of male rats were obviously irregular. In the offspring of male and female rats in the Wi-Fi group, the nucleus of hippocampal tissue contracted seriously, the cell membrane was irregular, and the cytoplasm appeared obvious edema. In the 1800 MHz+Wi-Fi group, the nuclei of hippocampal tissue of both male and female offspring rats were severely contracted, the nuclear membrane was irregular, and the cytoplasm was severely edema. there was no significant difference in FTO level among the groups (P>0.05) . Compared with other groups, NGF content in hippocampus of offspring rats in the 1800 MHz+Wi-Fi group was significantly higher (P<0.05) . Conclusion: Exposure to radio frequency electromagnetic fields will damage the morphological structure of hippocampal tissue of offspring and stimulate the increase of NGF expression in the hippocampus.

[Progress in research of influenza vaccine and 23 valent pneumococcal polysaccharide vaccine immunization in patients with chronic obstructive pulmonary disease]

A comprehensive review of the research of the effectiveness of influenza vaccine and 23 valent pneumococcal polysaccharide vaccine (PPV23) in patients with chronic obstructive pulmonary disease (COPD) both at home and abroad in recent years showed that influenza vaccine and PPV23 immunization can significantly reduce the risk for influenza and pneumonia in COPD patients, and reduce the acute exacerbation of disease and related hospitalization. In particular, the influenza vaccination can also reduce the risk for ischemic heart disease, acute coronary syndrome, ventricular arrhythmia, lung cancer, dementia and death in the patients, and the immunization of both vaccines has a more significant protective effect. It is recommended by authoritative guidelines both at home and abroad that COPD patients can receive influenza vaccine and PPV23. At present, the coverage of domestic influenza and pneumococcal vaccines are low, and there are less studies in the applications of both vaccines in patients with COPD. Effective measures should be taken to strengthen the health education and increase the vaccination coverage. Additionally, the clinical research of influenza vaccine and PPV23 for COPD patients, especially the analysis on clinical benefit of immunization of both vaccines, should be further strengthened to effectively improve the survival and prognosis of COPD patients.

Rashba-Edelstein Effect in the h-BN Van Der Waals Interface for Magnetization Switching

Van der Waals materials are attracting great attention in the field of spintronics due to their novel physical properties. For example, they are utilized as spin-current generating materials in spin-orbit torque (SOT) devices, which offers an electrical way to control the magnetic state and is promising for future low-power electronics. However, SOTs have mostly been demonstrated in vdW materials with strong spin-orbit coupling (SOC). Here, the observation of a current-induced SOT in the h-BN/SrRuO₃ bilayer structure is reported, where the vdW material (h-BN) is an insulator with negligible SOC. Importantly, this SOT is strong enough to induce the switching of the perpendicular magnetization in SrRuO₃ . First-principles calculations suggest a giant Rashba effect at the interface between vdW material and SrRuO₃ (110)_pc thin film, which leads to the observed SOT based on a simplified tight-binding model. Furthermore, it is demonstrated that the current-induced magnetization switching can be modulated by the electric field. This study paves the way for exploring the current-induced SOT and magnetization switching by integrating vdW materials with ferromagnets.

Multiscale biomechanics and mechanotransduction from liver fibrosis to cancer

A growing body of multiscale biomechanical studies has been proposed to highlight the mechanical cues in the development of hepatic fibrosis and cancer. At the cellular level, changes in mechanical microenvironment induce phenotypic and functional alterations of hepatic cells, initiating a positive feedback loop that promotes liver fibrogenesis and hepatocarcinogenesis. Tumor mechanical microenvironment of hepatocellular carcinoma facilitates tumor cell growth and metastasis, and hinders the drug delivery and immunotherapy. At the molecular level, mechanical forces are sensed and transmitted into hepatic cells via allosteric activation of mechanoreceptors on the cell membrane, leading to the activation of various mechanotransduction pathways including integrin and YAP signaling and then regulating cell function. Thus, the application of mechanomedicine concept in the treatment of liver diseases is promising for rational design and cell-specific delivery of therapeutic drugs. This review mainly discusses the correlation between biomechanical cues and liver diseases from the viewpoint of mechanobiology.

[Analysis of China's influenza vaccine application policy based on the macro model of the health system]

This article uses the analysis framework of the macro model of the health system to analyze the influenza vaccine policy documents issued by the state and governments at all levels from three perspectives: structure, process and results, and provides a scientific basis for improving the application strategy of influenza vaccine. It is suggested that on the basis of continuing to strengthen publicity, mobilization and organizational guarantee, measures to promote the application of influenza vaccine in China by exploring multi-channel financing mechanisms, combining the experience of new crown vaccination to improve the convenience of influenza vaccination, and scientifically setting vaccination rate targets, improve preparedness for an influenza pandemic.

Current-induced self-switching of perpendicular magnetization in CoPt single layer

All-electric switching of perpendicular magnetization is a prerequisite for the integration of fast, high-density, and low-power magnetic memories and magnetic logic devices into electric circuits. To date, the field-free spin-orbit torque (SOT) switching of perpendicular magnetization has been observed in SOT bilayer and trilayer systems through various asymmetric designs, which mainly aim to break the mirror symmetry. Here, we report that the perpendicular magnetization of Co_xPt_100-x single layers within a special composition range (20 < x < 56) can be deterministically switched by electrical current in the absence of external magnetic field. Specifically, the Co₃₀Pt₇₀ shows the largest out-of-plane effective field efficiency and best switching performance. We demonstrate that this unique property arises from the cooperation of two structural mechanisms: the low crystal symmetry property at the Co platelet/Pt interfaces and the composition gradient along the thickness direction. Compared with that in bilayers or trilayers, the field-free switching in Co_xPt_100-x single layer greatly simplifies the SOT structure and avoids additional asymmetric designs.

One challenge for spin-based electronics is the controlled and reliable switching of magnetization without magnetic fields. Here, Liu et al investigate a variety of compositions of CoPt, and determine the specific composition to maximize switching performance, potentially simplifying device design.

A Systematic Review and Meta-analysis of the Effect of Oral Exercises on Masticatory Function

The aim of the current systematic review was to summarize and to evaluate the available information on the effectiveness of oral exercise in improving the masticatory function of people ≥18 y. Electronic databases (Medline, Embase, CENTRAL) and gray literatures were searched (up to December 2020) for relevant randomized and nonrandomized controlled clinical trials. Two reviewers independently conducted the study selection, data extraction, and quality assessments. Meta-analysis was conducted for the comparison of bite force and masticatory performance using mean difference (MD) and standardized mean difference (SMD), respectively. GRADE (Grading of Recommendations Assessment, Development, and Evaluation) assessment was adopted for collective grading of the overall body of evidence. Of the 1,576 records identified, 18 studies (21 articles) were included in the analysis. Results of meta-analysis indicated that oral exercise could significantly improve the mean bite force of the participants (parallel comparison: MD, 41.2; 95% CI, 11.6-70.7, P = 0.006; longitudinal comparison: MD, 126.5; 95% CI, 105.2-144.9, P < 0.001). However, the improvement in masticatory performance was not significant (parallel comparison: SMD, 0.11; 95% CI, -0.20 to 0.42, P = 0.48; longitudinal comparison: SMD, 0.4; 95% CI, -0.11 to 0.91, P = 0.13). Results of meta-regression showed that greater improvements in bite force can be achieved among younger adults and with more intensive exercise. Chewing exercise is the most effective oral exercise, followed by clenching exercise, while simple oral exercise may not have a significant effect. Based on the results of the meta-analysis and GRADE assessment, a weak recommendation for people with declined masticatory function to practice oral exercise is made.

Electric Field Control of the Magnetic Weyl Fermion in an Epitaxial SrRuO3 (111) Thin Film

The magnetic Weyl fermion originates from the time reversal symmetry (TRS)-breaking in magnetic crystalline structures, where the topology and magnetism entangle with each other. Therefore, the magnetic Weyl fermion is expected to be effectively tuned by the magnetic field and electrical field, which holds promise for future topologically protected electronics. However, the electrical field control of the magnetic Weyl fermion has rarely been reported, which is prevented by the limited number of identified magnetic Weyl solids. Here, the electric field control of the magnetic Weyl fermion is demonstrated in an epitaxial SrRuO₃ (111) thin film. The magnetic Weyl fermion in the SrRuO₃ films is indicated by the chiral anomaly induced magnetotransport, and is verified by the observed Weyl nodes in the electronic structures characterized by the angle-resolved photoemission spectroscopy (ARPES) and first-principles calculations. Through the ionic-liquid gating experiment, the effective manipulation of the Weyl fermion by electric field is demonstrated, in terms of the sign-change of the ordinary Hall effect, the nonmonotonic tuning of the anomalous Hall effect, and the observation of the linear magnetoresistance under proper gating voltages. The work may stimulate the searching and tuning of Weyl fermions in other magnetic materials, which are promising in energy-efficient electronics.

Spin-Orbit Torque-Induced Domain Nucleation for Neuromorphic Computing

Neuromorphic computing has become an increasingly popular approach for artificial intelligence because it can perform cognitive tasks more efficiently than conventional computers. However, it remains challenging to develop dedicated hardware for artificial neural networks. Here, a simple bilayer spintronic device for hardware implementation of neuromorphic computing is demonstrated. In L1₁ -CuPt/CoPt bilayer, current-inducted field-free magnetization switching by symmetry-dependent spin-orbit torques shows a unique domain nucleation-dominated magnetization reversal, which is not accessible in conventional bilayers. Gradual domain nucleation creates multiple intermediate magnetization states which form the basis of a sigmoidal neuron. Using the L1₁ -CuPt/CoPt bilayer as a sigmoidal neuron, the training of a deep learning network to recognize written digits, with a high recognition rate (87.5%) comparable to simulation (87.8%) is further demonstrated. This work offers a new scheme of implementing artificial neural networks by magnetic domain nucleation.

Modulation of Spin-Orbit Torque from SrRuO3 by Epitaxial-Strain-Induced Octahedral Rotation

Spin-orbit torque (SOT), which arises from the spin-orbit coupling of conduction electrons, is believed to be the key route for developing low-power, high-speed, and nonvolatile memory devices. Despite the theoretical prediction of pronounced Berry phase curvatures in certain transition-metal perovskite oxides, which lead to considerable intrinsic spin Hall conductivity, SOT from this class of materials has rarely been reported until recently. Here, the SOT generated by epitaxial SrRuO₃ of three different crystal structures is systematically studied. The results of both spin-torque ferromagnetic resonance and in-plane harmonic Hall voltage measurements concurrently reveal that the intrinsic SOT efficiency of SrRuO₃ decreases when the epitaxial strain changes from tensile to compressive. The X-ray diffraction data demonstrate a strong correlation between the magnitude of SOT and octahedral rotation around the in-plane axes of SrRuO₃ , consistent with the theoretical prediction. This work offers new possibilities of tuning SOT with crystal structures and novel opportunities of integrating the unique properties of perovskite oxides with spintronic functionalities.

[Evaluation of safety of two inactivated COVID-19 vaccines in a large-scale emergency use]

Objective: To evaluate the safety of two inactivated COVID-19 vaccines in a large-scale emergency use. Methods: Based on the "Vaccination Information Collection System", the incidence data of adverse reactions in the population vaccinated with the inactivated COVID-19 vaccines developed by Beijing Institute of Biological Products Co., Ltd and Wuhan Institute of Biological Products Co., Ltd, respectively, in emergency use were collected, and the relevant information were analyzed with descriptive epidemiological and statistical methods. Results: By December 1, 2020, the vaccination information of 519 543 individuals had been collected. The overall incidence rate of adverse reactions was 1.06%, the incidence rate of systemic adverse reactions was 0.69% and the incidence rate of local adverse reactions was 0.37%. The main systemic adverse reactions included fatigue, headache, fever, cough and loss of appetite with the incidence rates of 0.21%, 0.14%, 0.06%, 0.05% and 0.05%, respectively; the main local adverse reactions were injection site pain and injection site swelling with the incidence rates of 0.24% and 0.05%, respectively. Conclusion: The two inactivated COVID-19 vaccines by Beijing Institute of Biological Products Co., Ltd and Wuhan Institute of Biological Products Co., Ltd showed that in the large-scale emergency use, the incidence rate of general reactions was low and no serious adverse reactions were observed after the vaccinations, demonstrating that the vaccines have good safety.

Hepatic differentiation of human embryonic stem cells by coupling substrate stiffness and microtopography

Mechanical or physical cues are associated with the growth and differentiation of embryonic stem cells (ESCs). While the substrate stiffness or topography independently affects the differentiation of ESCs, their cooperative regulation on lineage-specific differentiation remains largely unknown. Here, four topographical configurations on stiff or soft polyacrylamide hydrogel were combined to direct hepatic differentiation of human H1 cells via a four-stage protocol, and the coupled impacts of stiffness and topography were quantified at distinct stages. Data indicated that the substrate stiffness is dominant in stemness maintenance on stiff gel and hepatic differentiation on soft gel while substrate topography assists the differentiation of hepatocyte-like cells in positive correlation with the circularity of H1 clones initially formed on the substrate. The differentiated cells exhibited liver-specific functions such as maintaining the capacities of CYP450 metabolism, glycogen synthesis, ICG engulfment, and repairing liver injury in CCl4-treated mice. These results implied that the coupling of substrate stiffness and topography, combined with the biochemical signals, is favorable to improve the efficiency and functionality of hepatic differentiation of human ESCs.

Spin-Orbit Torque Switching of a High-Quality Perpendicularly Magnetized Ferrimagnetic Heusler Mn3Ge Film

Current-induced spin-orbit torque (SOT) switching of magnetization has attracted great interest due to its potential application in magnetic memory devices, which offer low-energy consumption and high-speed writing. However, most of the SOT studies on perpendicularly magnetized anisotropy (PMA) magnets have been limited to heterostructures with interfacial PMA and poor thermal stability. Here, we experimentally demonstrate a SOT magnetization switching for a ferrimagnetic D0₂₂-Mn₃Ge film with high bulk PMA and robust thermal stability factor under a critical current density of 6.6 × 10¹¹ A m^-2 through the spin Hall effect of an adjacent capping Pt and a buffer Cr layer. A large effective damping-like SOT efficiency of 2.37 mT/10¹⁰ A m^-2 is determined using harmonic measurements in the structure. The effect of the double-spin source layers and the negative-exchange interaction of the ferrimagnet may explain the large SOT efficiency and the manifested magnetization switching of Mn₃Ge. Our findings demonstrate that D0₂₂-Mn₃Ge is a promising candidate for application in high-density SOT magnetic random-access memory devices.

Symmetry-dependent field-free switching of perpendicular magnetization

Modern magnetic-memory technology requires all-electric control of perpendicular magnetization with low energy consumption. While spin-orbit torque (SOT) in heavy metal/ferromagnet (HM/FM) heterostructures^1-5 holds promise for applications in magnetic random access memory, until today, it has been limited to the in-plane direction. Such in-plane torque can switch perpendicular magnetization only deterministically with the help of additional symmetry breaking, for example, through the application of an external magnetic field^2,4, an interlayer/exchange coupling^6-9 or an asymmetric design^10-14. Instead, an out-of-plane SOT¹⁵ could directly switch perpendicular magnetization. Here we observe an out-of-plane SOT in an HM/FM bilayer of L1₁-ordered CuPt/CoPt and demonstrate field-free switching of the perpendicular magnetization of the CoPt layer. The low-symmetry point group (3m1) at the CuPt/CoPt interface gives rise to this spin torque, hereinafter referred to as 3m torque, which strongly depends on the relative orientation of the current flow and the crystal symmetry. We observe a three-fold angular dependence in both the field-free switching and the current-induced out-of-plane effective field. Because of the intrinsic nature of the 3m torque, the field-free switching in CuPt/CoPt shows good endurance in cycling experiments. Experiments involving a wide variety of SOT bilayers with low-symmetry point groups^16,17 at the interface may reveal further unconventional spin torques in the future.

Mutations in CHMP4C cause dilated cardiomyopathy via dysregulation of autophagy

Background

Gene mutations have been implicated in DCM. However, due to the difficulty of clinical genetic diagnosis, more causal genes potentially related to DCM remain to be discovered.

Methods

We screened for gene mutations in more than 400 cases from families with hereditary cardiovascular disease using whole-exome sequencing. Then we validated biological functions of CHMP4C mutations in zebrafish models. To further assess the mechanism of CHMP4C mutations, we evaluated the potential signaling pathway in the cells.

Results

We identification of CHMP4C variants that segregated with DCM variants in four families from a total of 411 families via whole-exome sequencing. We further validate the function of CHMP4C in heart function in zebrafish models and found that over-expression of CHMP4C variants in zebrafish resulted in cardiac malformation, pericardial edema and increased heart rate, consistent with CHMP4C mutation-associated findings in DCM patients. Furthermore, we found that mutations in CHMP4C impaired autophagy and activated apoptosis in HEK293T cells, suggesting that the molecular mechanism of CHMP4C is involved in heart development.

Conclusions

CHMP4C is a novel candidate gene for DCM and may play a critical role in cardiac development by regulating autophagy.

Funding Acknowledgement

Type of funding source: None

Non-invasive myocardial workiIndices derived from left ventricular pressure-strain loops in predicting the response to cardiac resynchronization therapy

Background

Non-invasive left ventricular (LV) pressure-strain loops (PSLs) which generated by combining LV longitudinal strain with brachial artery blood pressure, provide a novel method of quantifying global and segmental myocardial work (MW) indices with potential advantages over conventional echocardiographic strain which is load-dependent. The method has been introduced in echocardiographic software recently, making MW calculations more effectively and rapidly. The aim was to evaluate the role of non-invasive MW indices derived from LV PSLs in the prediction of cardiac resynchronization therapy (CRT) response.

Methods

106 heart failure (HF) patients scheduled for CRT were included for MW analysis. Global and segmental (septal and lateral at the mid-ventricular level) MW indices were accessed before CRT. Response to CRT was defined as ≥15% reduction in LV end-systolic volume at 6-month follow-up in comparison with baseline value.

Results

CRT response was observed in 78 (74%) patients. At baseline, global work index (GWI) and global constructive work (GCW) were significant higher in CRT responders than in non-responders (both P&lt;0.05). Besides, responders exhibited a significantly higher Mid Lateral MW and Mid Lateral constructive work (CW) (both P&lt;0.001) but a significantly lower Mid Septal MW and Mid Septal myocardial work efficiency (MWE), as well as a significantly higher Mid Septal wasted work (WW) than non-responders (all P&lt;0.01). Baseline Mid Septal MWE (OR 0.975, 95% CI 0.959–0.990, P=0.002) and Mid Lateral MW (OR 1.003, 95% CI 1.002–1.004, P&lt;0.001) were identified as independent predictors of CRT response in multivariate regression analysis. Mid Septal MWE ≤42% combined with Mid Lateral MW ≥740 mm Hg% predicted CRT response with the optimal sensitivity of 79% and specificity of 82% (AUC = 0.830, P&lt;0.001).

Conclusion

Mid Septal MWE and Mid Lateral MW can successfully predict response to CRT, and their combination can further improve the prediction accuracy. Assessment of MW indices before CRT could identify the marked misbalance in LV myocardial work distribution and has the potential to be widely used as a reliable complementary tool for guiding patient selection in clinical practice.

Funding Acknowledgement

Type of funding source: None

Perpendicular Magnetic Anisotropy and Dzyaloshinskii-Moriya Interaction at an Oxide/Ferromagnetic Metal Interface

We report on the study of both perpendicular magnetic anisotropy (PMA) and Dzyaloshinskii-Moriya interaction (DMI) at an oxide/ferromagnetic metal (FM) interface, i.e., BaTiO_{3} (BTO)/CoFeB. Thanks to the functional properties of the BTO film and the capability to precisely control its growth, we are able to distinguish the dominant role of the oxide termination (TiO_{2} vs BaO) from the moderate effect of ferroelectric polarization in the BTO film, on the PMA and DMI at an oxide/FM interface. We find that the interfacial magnetic anisotropy energy of the BaO-BTO/CoFeB structure is 2 times larger than that of the TiO_{2}-BTO/CoFeB, while the DMI of the TiO_{2}-BTO/CoFeB interface is larger. We explain the observed phenomena by first principles calculations, which ascribe them to the different electronic states around the Fermi level at oxide/ferromagnetic metal interfaces and the different spin-flip process. This study paves the way for further investigation of the PMA and DMI at various oxide/FM structures and thus their applications in the promising field of energy-efficient devices.

Continuously controllable photoconductance in freestanding BiFeO3 by the macroscopic flexoelectric effect

Flexoelectricity induced by the strain gradient is attracting much attention due to its potential applications in electronic devices. Here, by combining a tunable flexoelectric effect and the ferroelectric photovoltaic effect, we demonstrate the continuous tunability of photoconductance in BiFeO3 films. The BiFeO3 film epitaxially grown on SrTiO3 is transferred to a flexible substrate by dissolving a sacrificing layer. The tunable flexoelectricity is achieved by bending the flexible substrate which induces a nonuniform lattice distortion in BiFeO3 and thus influences the inversion asymmetry of the film. Multilevel conductance is thus realized through the coupling between flexoelectric and ferroelectric photovoltaic effect in freestanding BiFeO3. The strain gradient induced multilevel photoconductance shows very good reproducibility by bending the flexible BiFeO3 device. This control strategy offers an alternative degree of freedom to tailor the physical properties of flexible devices and thus provides a compelling toolbox for flexible materials in a wide range of applications.

Association between methylenetetrahydrofolate reductase polymorphisms and non-syndromic cleft lip with or without palate susceptibility: an updated systematic review and meta-analysis

Methylenetetrahydrofolate reductase (MTHFR) polymorphisms are thought to be involved in the development of cleft lip with or without cleft palate (NSCL/P), but published results are contradictory. We therefore designed an updated meta-analysis to pool eligible studies and to evaluate further the possible relations between MTHFR polymorphisms (c.677C>T and c.1298A>C) and susceptibility to NSCL/P. A comprehensive search based on PubMed, Medline, Web of Science, and Embase databases was made up to February 2018. Twenty-three case-control and 10 case-parent trio studies (including 1149 cases and 1161 controls) were retrieved. Odds ratio (OR) with 95% CI were used to estimate the pooled strength of association under different genetic models. The Q test and I² test were used to estimate heterogeneity among studies, the quality of which was assessed using the Newcastle-Ottawa scale. In the MTHFR c.677C>T polymorphism group, there were significant overall results for the recessive (OR 1.231, 95%CI 1.092 to 1.387) and homozygote (OR 1.252, 95%CI 1.078 to 1.456) models. Subgroup analysis by subjects and ethnicity identified only associations in European mothers for the recessive model and the homozygote model. For the c.1298A>C group, there were no significant results for either European or Asian patients for all genetic models. The MTHFR c.677C>T polymorphism might increase susceptibility to NSCL/P in European mothers, but was negatively associated in Asian patients, and the MTHFR c.1298A>C polymorphism is not involved in the development of NSCL/P in either European or Asian patients.

P6501Recurrent genetic aberrations in bicuspid aortic valve disease patients with isolated severe aortic regurgitation

Background

The etiology of bicuspid aortic valve disease (BAVD) is still unclear. Recent studies have demonstrated elevated prevalence of genetic defects in BAV patients with root phenotype, which includes aortic regurgitation and root-predominant dilatation.

Purpose

The present study intended to illustrate the feature of genetic defects among early-onset BAV patients with isolated severe aortic regurgitation.

Methods

From June 2015 to December 2017, whole exome sequencing was performed upon 27 BAVD patients with isolated severe aortic regurgitation under 45 years in our institution. Patients were categorized into right-left (R-L, n=16) and non-RL (n=11) cusp fusion types, and those with complex cardiac defects were excluded from the present study.

Results

Among 27 patients with a median age of 30.5 (18–44) years, only one was female with a rare left-non-coronary cusp fusion type. The prevalence of root phenotype was markedly higher in RL patients (56.3% vs 9.1%, p=0.018). In RL patients, the numbers of rare genetic variants (RGVs) were 15 in extracellular matrix genes, 8 in TGF-β signaling pathway genes, 2 in smooth muscle cell contraction apparatus genes, and 3 in familiar BAV related genes. In non-RL patients, the number of RGVs were 15, 3, 4, and 5, respectively. On the other hand, the number of RGVs in above gene clusters were 9, 6, 3, 2 in patients with a root phenotype, and 21, 5, 3, 6 in those without. Eight recurrent genetic variants were identified in 6 genes (see Table). An interesting observation was that ADAMTS2 variants were exclusively found among non-RL patients without root phenotype, as FBN2 variants among RL patients with root phenoype.

Recurrent Rare Genetic Variants Gene Reference sequence Variant 1000G 1000G-East Asia Patients TGFBR2 NM_001024847.2 p.Val216Ile/c.646G>A 0.004 0.018 A16, A23 TGFBR2 NM_001024847.2 p.Thr340Met/c.1019C>T 0.003 0.015 A03, A05, A07 ADAMTS2 NM_014244.4 p.Gly1169Val/c.3506G>T 0.0044 0.021 A03, A15 FBN2 NM_001999.3 p.Gly475Val/c.1424G>T 0.0004 0.002 A19, A24 ELN NM_001278939.1 p.Pro93Leu/c.278C>T 0.0014 0.0069 A22, A26 COL4A5 NM_033380.2 p.Gly953Val/c.2858G>T 0.0079 0.03 A11, A17 MYLK NM_053025.3 p.Ser243Trp/c.728C>G 0.0002 0.001 A01, A02 MYLK NM_053025.3 p.Asp717Tyr/c.2149G>T 0.0024 0.011 A04, A21

Conclusion

Recurrent genetic variants could be identified in a cohort of early-onset BAVD patients with isolated severe aortic regurgitation and staggering male predominance. The incidence and clinical relevance of these variants should be validated in an extended real-world BAV cohort.

Current-induced magnetization switching in all-oxide heterostructures

The electrical switching of magnetization through spin-orbit torque (SOT)¹ holds promise for application in information technologies, such as low-power, non-volatile magnetic memory. Materials with strong spin-orbit coupling, such as heavy metals^2-4 and topological insulators^5,6, can convert a charge current into a spin current. The spin current can then execute a transfer torque on the magnetization of a neighbouring magnetic layer, usually a ferromagnetic metal like CoFeB, and reverse its magnetization. Here, we combine a ferromagnetic transition metal oxide⁷ with an oxide with strong spin-orbit coupling⁸ to demonstrate all-oxide SOT devices. We show current-induced magnetization switching in SrIrO₃/SrRuO₃ bilayer structures. By controlling the magnetocrystalline anisotropy of SrRuO₃ on (001)- and (110)-oriented SrTiO₃ (STO) substrates, we designed two types of SOT switching schemes. For the bilayer on the STO(001) substrate, a magnetic-field-free switching was achieved, which remained undisturbed even when the external magnetic field reached 100 mT. The charge-to-spin conversion efficiency for the bilayer on the STO(110) substrate ranged from 0.58 to 0.86, depending on the directionality of the current flow with respect to the crystalline symmetry. All-oxide SOT structures may help to realize field-free switching through a magnetocrystalline anisotropy design.

P916The effect of a novel, user-friendly, transcatheter edge-to-edge mitral valve repair device in a porcine model of mitral regurgitation

Objective

A new technique has been devised to treat mitral regurgitation (MR) through the transapical route by replicating the edge-to-edge repair surgery. This system encompasses an easy-to-use leaflet clamp and a smaller-sized delivery system (14F–16F). We aimed to evaluate the effectiveness of this device in a porcine model of acute MR.

Methods

Acute MR was induced in 36 anesthetized porcine subjects by severing the major chordae supporting the corresponding segment of the leaflet. This device was then transapically implanted on the prolapsing segment under 3D epicardial echocardiographic guidance. All of the animals were killed 30 days after the procedure to verify the proper location of the implanted devices.

Results

Cutting the major chordae induced an eccentric MR jet (MR grade: 3+, 27.8%/4+, 72.2%) in all of the animals. Every single pig was then successfully implanted with one clamp. The duration of catheterization ranged from 18 to 40 minutes. Overt MR reduction was observed following the procedure through echocardiography; residual MR was mild in 8 cases, trivial in 19 cases, and absent in 9 cases. In terms of hemodynamic parameters, the mean and maximum mitral valve pressure gradients were increased significantly (p<0.01), but these values were less than 4 mmHg in all of the cases. Autopsy demonstrated that all but one device were precisely placed to clip the prolapsing segment of the mitral valve, and there was no evidence of thrombosis, thromboembolism or impairment of the cardiac structure.

Table 1. Changes in hemodynamic parameters, cardiac size, and functional parameters after the procedure Preoperation Postoperation P value MR-maxA (mm2) 7.27±2.13 1.54±1.29 0.000 MVPG-max (mmHg) 1.95±0.47 3.66±0.62 0.000 MVPG-mean (mmHg) 0.87±0.31 1.7±0.28 0.000 LVEDD (mm) 46.08±2.85 46.44±3.53 0.239 LVESD (mm) 29.11±3.44 29.08±3.62 0.940 LVEF (%) 66.53±6.4 67.14±4.93 0.256 LAD (mm) 35.75±2.24 36.42±1.99 0.057 LAA (mm2) 12.95±2.22 12.64±1.55 0.301

Figure 1

Conclusions

Transapical implantation of the novel mitral valve repair device is effective and safe in reducing acutely induced MR in pigs; thus, suggesting that it has great potential for clinical benefit in patients with MR.

Acknowledgement/Funding

Shanghai Science and Technology Committee

Free Field Electric Switching of Perpendicularly Magnetized Thin Film by Spin Current Gradient

To realize high-speed nonvolatile magnetic memory with low energy consumption, electric switching of perpendicular magnetization by spin-orbit torque in the heavy metal/ferromagnetic (HM/FM) structure has recently attracted intensive attention. Conventionally, an external in-plane magnetic field for breaking the symmetry is required for achieving electric switching of perpendicular magnetization. However, electric switching without external field is the prerequisite for the integration of magnetic functionality into the integrated circuit devices. Here, we propose a new method of utilizing a W wedge in the Pt/W/FM structure to induce a spin current gradient, which can result in an in-plane equivalent field along the wedge thickness gradient direction. We experimentally demonstrate the deterministic magnetization switching of perpendicular Co/Ni multilayers without external magnetic field when the electric current is along the wedge thickness gradient direction. Our findings shed light on free field electric switching of magnetization by a new physical parameter-an asymmetric spin current induced by a bilayer wedge structure.

Giant Enhancements of Perpendicular Magnetic Anisotropy and Spin-Orbit Torque by a MoS2 Layer

2D transition metal dichalcogenides have attracted much attention in the field of spintronics due to their rich spin-dependent properties. The promise of highly compact and low-energy-consumption spin-orbit torque (SOT) devices motivates the search for structures and materials that can satisfy the requirements of giant perpendicular magnetic anisotropy (PMA) and large SOT simultaneously in SOT-based magnetic memory. Here, it is demonstrated that PMA and SOT in a heavy metal/transition metal ferromagnet structure, Pt/[Co/Ni]₂ , can be greatly enhanced by introducing a molybdenum disulfide (MoS₂ ) underlayer. According to first-principles calculation and X-ray absorption spectroscopy (XAS), the enhancement of the PMA is ascribed to the modification of the orbital hybridization at the interface of Pt/Co due to MoS₂ . The enhancement of SOT by the role played by MoS₂ is explained, which is strongly supported by the identical behavior of SOT and PMA as a function of Pt thickness. This work provides new possibilities to integrate 2D materials into promising spintronics devices.

Large spin-orbit torque efficiency enhanced by magnetic structure of collinear antiferromagnet IrMn

Spin-orbit torque (SOT) offers promising approaches to developing energy-efficient memory devices by electric switching of magnetization. Compared to other SOT materials, metallic antiferromagnet (AFM) potentially allows the control of SOT through its magnetic structure. Here, combining the results from neutron diffraction and spin-torque ferromagnetic resonance experiments, we show that the magnetic structure of epitaxially grown L1₀-IrMn (a collinear AFM) is distinct from the widely presumed bulk one. It consists of twin domains, with the spin axes orienting toward [111] and [-111], respectively. This unconventional magnetic structure is responsible for much larger SOT efficiencies up to 0.60 ± 0.04, compared to 0.083 ± 0.002 for the polycrystalline IrMn. Furthermore, we reveal that this magnetic structure induces a large isotropic bulk contribution and a comparable anisotropic interfacial contribution to the SOT efficiency. Our findings shed light on the critical roles of bulk and interfacial antiferromagnetism to SOT generated by metallic AFM.

Vitamin B6 catabolism and lung cancer risk: results from the Lung Cancer Cohort Consortium (LC3)

BACKGROUND

Increased vitamin B6 catabolism related to inflammation, as measured by the PAr index (the ratio of 4-pyridoxic acid over the sum of pyridoxal and pyridoxal-5'-phosphate), has been positively associated with lung cancer risk in two prospective European studies. However, the extent to which this association translates to more diverse populations is not known.

MATERIALS AND METHODS

For this study, we included 5323 incident lung cancer cases and 5323 controls individually matched by age, sex, and smoking status within each of 20 prospective cohorts from the Lung Cancer Cohort Consortium. Cohort-specific odds ratios (ORs) and 95% confidence intervals (CIs) for the association between PAr and lung cancer risk were calculated using conditional logistic regression and pooled using random-effects models.

RESULTS

PAr was positively associated with lung cancer risk in a dose-response fashion. Comparing the fourth versus first quartiles of PAr resulted in an OR of 1.38 (95% CI: 1.19-1.59) for overall lung cancer risk. The association between PAr and lung cancer risk was most prominent in former smokers (OR: 1.69, 95% CI: 1.36-2.10), men (OR: 1.60, 95% CI: 1.28-2.00), and for cancers diagnosed within 3 years of blood draw (OR: 1.73, 95% CI: 1.34-2.23).

CONCLUSION

Based on pre-diagnostic data from 20 cohorts across 4 continents, this study confirms that increased vitamin B6 catabolism related to inflammation and immune activation is associated with a higher risk of developing lung cancer. Moreover, PAr may be a pre-diagnostic marker of lung cancer rather than a causal factor.

Emergence of Topological Hall Effect in a SrRuO3 Single Layer

Topological Hall effect (THE), appearing as bumps and/or dips in the Hall resistance curves, is considered as a hallmark of the skyrmion spin texture originated from the inversion symmetry breaking and spin-orbit interaction. Recently, Néel-type skyrmion is proposed based on the observed THE in 5d transition metal oxides heterostructures such as SrRuO₃ /SrIrO₃ bilayers, where the interfacial Dzyaloshinskii-Moriya interaction (DMI), due to the strong spin-orbit coupling (SOC) in SrIrO₃ and the broken inversion symmetry at the interface, is believed to play a significant role. Here the emergence of THE in SrRuO₃ single layers with thickness ranging from 3 to 6 nm is experimentally demonstrated. It is found that the oxygen octahedron rotation in SrRuO₃ also has a significant effect on the observed THE. Furthermore, the THE may be continuously tuned by an applied electrical field. It is proposed that the large SOC of Ru ions together with the broken inversion symmetry, mainly from the interface, produce the DMI that is responsible for the observed THE. The emergence of the gate-tunable DMI in SrRuO₃ single layer may stimulate further investigations of new spin-orbit physics in strong SOC oxides.

Surface Energy Driven Liquid-Drop-Like Pseudoelastic Behaviors and In Situ Atomistic Mechanisms of Small-Sized Face-Centered-Cubic Metals

The elastic strain of conventional metals is usually below ∼1%. As the metals' sizes decrease to approximate a few nanometers, their elastic strains can approach ∼8%, and they usually exhibit pseudoelastic strain that can be as large as ∼35%. Previous studies suggested that the pseudoelastic behaviors of nanocrystals were attributed to distinctive mechanisms, including the release of stored elastic energies, the temperature-enhanced surface diffusion, etc. However, the atomistic mechanisms remain elusive. In this study, through large numbers of in situ atomic-scale tensile-fracture experiments, we report liquid-drop-like pseudoelastic behaviors of face-centered-cubic fractured single-crystalline nanowires with diameters varying from 0.5 to 2.2 nm. The ultralarge liquid-drop-like pseudoelastic strain ranged from 31.4% to 81.0% after the nanowire fracture was observed. The in situ atomic-scale investigations revealed that the atomistic mechanisms resulted from surface energy driven plastic deformation including surface diffusion mixed with shear plastic deformation as well as the release of true elastic energy. As the nanowires' diameters decrease below a critical value, the surface pressure can approach the ideal strength of metals. This ultralarge surface pressure drives atoms to diffuse mixed with dislocation nucleation/propagation, which ultimately leads to the fractured nanowires exhibiting liquid-drop-like pseudoelastic phenomena.

Comparison of two kinds of skin imaging analysis software: VISIA® from Canfield and IPP® from Media Cybernetics

BACKGROUND

Skin imaging analysis, acting as a supplement to noninvasive bioengineering devices, has been widely used in medical cosmetology and cosmetic product evaluation. The main aim of this study is to assess the differences and correlations in measuring skin spots, wrinkles, vascular features, porphyrin, and pore between two commercially available image analysis software.

MATERIALS AND METHODS

Seventy healthy women were included in the study. Before taking pictures, the dermatologist evaluated subjects' skin conditions. Test sites included the forehead, cheek, and periorbital skin. A 2 × 2 cm cardboard was used to make a mark on the skin surface. Pictures were taken using VISIA^® under three kinds light conditions and analyzed using VISIA^® and IPP^® respectively.

RESULTS

(1) Skin pore, red area, ultraviolet spot, brown spot, porphyrin, and wrinkle measured with VISIA^® were correlated with those measured with IPP^® (P < .01). (2) Spot, wrinkle, fine line, brown spot, and red area analyzed with VISIA^® were correlated with age on the forehead and periorbital skin (P < .05). L-value, Crow's feet, ultraviolet spot, brown spot, and red area analyzed with IPP^® were correlated with age on the periorbital skin (P < .05). (3) L-value, spot, wrinkle, fine line, porphyrin, red area, and pore analyzed with VISIA^® and IPP^® showed correlations with the subjective evaluation scores (P < .05).

CONCLUSIONS

VISIA^® and IPP^® showed acceptable correlation in measuring various skin conditions. VISIA^® showed a high sensibility when measured on the forehead skin. IPP^® is available as an alternative software program to evaluate skin features.

Salt bridge interactions within the β2 integrin α7 helix mediate force-induced binding and shear resistance ability

The functional performance of the αI domain α₇ helix in β₂ integrin activation depends on the allostery of the α₇ helix, which axially slides down; therefore, it is critical to elucidate what factors regulate the allostery. In this study, we determined that there were two conservative salt bridge interaction pairs that constrain both the upper and bottom ends of the α₇ helix. Molecular dynamics (MD) simulations for three β₂ integrin members, lymphocyte function-associated antigen-1 (LFA-1; α_L β₂ ), macrophage-1 antigen (Mac-1; α_M β₂ ) and α_x β₂ , indicated that the magnitude of the salt bridge interaction is related to the stability of the αI domain and the strength of the corresponding force-induced allostery. The disruption of the salt bridge interaction, especially with double mutations in both salt bridges, significantly reduced the force-induced allostery time for all three members. The effects of salt bridge interactions of the αI domain α₇ helix on β₂ integrin conformational stability and allostery were experimentally validated using Mac-1 constructs. The results demonstrated that salt bridge mutations did not alter the conformational state of Mac-1, but they did increase the force-induced ligand binding and shear resistance ability, which was consistent with MD simulations. This study offers new insight into the importance of salt bridge interaction constraints of the αI domain α₇ helix and external force for β₂ integrin function.

Primary antibiotic resistance of Helicobacter pylori in Chinese patients: a multiregion prospective 7-year study

OBJECTIVES

To explore the characteristics of Helicobacter pylori resistance in China and the association between antibiotic resistance and several clinical factors.

METHODS

H. pylori strains were collected from patients in 13 provinces or cities in China between 2010 and 2016. Demographic data including type of disease, geographic area, age, gender and isolation year were collected to analyse their association with antibiotic resistance. Antibiotic resistance was detected using the Etest test and the Kirby-Bauer disc diffusion method.

RESULTS

H. pylori were successfully cultured from 1117 patients. The prevalence of metronidazole, clarithromycin (CLA), azithromycin, levofloxacin (LEV), moxifloxacin, amoxicillin (AMO), tetracycline and rifampicin resistance was 78.2, 22.1, 23.3, 19.2, 17.2, 3.4, 1.9 and 1.5%, respectively. No resistance to furazolidone was observed. The resistance rates to LEV and moxifloxacin were higher in strains isolated from patients with gastritis compared to those with duodenal ulcer and among women. Compared to patients ≥40 years old, younger patients exhibited lower resistance rates to CLA, azithromycin, LEV and moxifloxacin. The resistance rates to CLA and AMO were higher in strains isolated more recently, and we also found that the prevalence of resistance to metronidazole, CLA, azithromycin and AMO were significantly different among different regions of China.

CONCLUSIONS

The resistance rates to metronidazole, CLA and LEV were high in China. Patient age, gender, disease and location were associated with the resistance of H. pylori to some antibiotics. Furazolidone, AMO and tetracycline are better choices for H. pylori treatment in China.

Size effect on the deformation mechanisms of nanocrystalline platinum thin films

This paper reports a study of time-resolved deformation process at the atomic scale of a nanocrystalline Pt thin film captured in situ under a transmission electron microscope. The main mechanism of plastic deformation was found to evolve from full dislocation activity-enabled plasticity in large grains (with grain size d > 10 nm), to partial dislocation plasticity in smaller grains (with grain size 10 nm < d < 6 nm), and grain boundary-mediated plasticity in the matrix with grain sizes d < 6 nm. The critical grain size for the transition from full dislocation activity to partial dislocation activity was estimated based on consideration of stacking fault energy. For grain boundary-mediated plasticity, the possible contributions to strain rate of grain creep, grain sliding and grain rotation to plastic deformation were estimated using established models. The contribution of grain creep is found to be negligible, the contribution of grain rotation is effective but limited in magnitude, and grain sliding is suggested to be the dominant deformation mechanism in nanocrystalline Pt thin films. This study provided the direct evidence of these deformation processes at the atomic scale.