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Recently, a new sub-branch Ⅰb of Mpox virus (MPXV) has triggered a new round of Mpox outbreak. 2024-08-14, Mpox was once again classified as a public health emergency of international concern (PHEIC) by the WHO. Early detection and diagnosis of Mpox cases is the key to interrupting the spread of Mpox in hospitals. In this article, we will review the pathogenetic features, epidemiological features, clinical features, diagnostic criteria, preventive and control measures of Mpox, with a view to providing reference for the early identification, scientific prevention and control of Mpox.

ObjectiveTo analyze the characteristics of forensic clinical sex identification cases after sex reassignment surgery for transsexualism, discuss the main point of forensic clinical sex identification in China based on domestic and foreign sex change policies and related cases, so as to standardize relevant identification.MethodsA total of 39 cases of forensic clinical sex identification were collected from Center for Forensic Science, Shanghai Medical College of Fudan University in recent years, and the ratio of sex, identification time, the location of surgery, secondary sex characteristic and other information were statistically analyzed.ResultsTransgender woman accounted for 97.4% of the cases, and 94.9% of the cases were operated in Thailand. All cases were identified after the sex reassignment surgery, and at least one of the secondary sex characteristics was consistent with the postoperative primary sexual characters. There were only 2 cases in which auxiliary examination was applied.ConclusionForensic clinical sex identification should be based on the principle that the primary and secondary sex characteristics are consistent with the changed sex.

Mycotoxins are toxic secondary metabolites produced by certain fungal species under specific conditions. Research has found that exposure to various fungal toxins can cause embryonic developmental toxicity, such as embryo arrest, abortion, and intrauterine fetal developmental delay. There are no systematic reports on the impact of exposure to fungal toxins during pregnancy on the toxicity of intrauterine fetal development and biological monitoring. Therefore, in order to prevent and reduce the harm of fungal toxins during pregnancy, this paper summarizes the research status of embryonic developmental toxicity, as well as the research status of biological monitoring technologies based on biomarkers such as exposure biomarkers and biomakers of effect, which are caused by traditional fungal toxins such as aflatoxin, deoxynivalenol, zearalenone, and emerging fungal toxins such as Alternaria toxins, beauverin, and enniatins. The aim of the paper is for construction of the healthy China.

[Objective] Registered impoverished farmers’ sense of gain is crucial for determining the achievements of poverty alleviation relocation. This study aims to examine the impact of individual income inequality on sense of gain of farmers relocated for poverty alleviation and its mechanism after poverty alleviation relocation. [Methods] Based on the relative deprivation theory and data from 1202 questionnaires of farmers relocated for poverty alleviation collected in four cities and eight counties (districts) in Shaanxi Province in 2021, this study explores the relationship between individual income inequality, relocated farmers’ sense of gain, and social integration by using an ordered-probit model and the mediation effect model. [Results] (1) On the whole, the surveyed farmers think the gains outweigh the losses from the poverty alleviation relocation. However, individual income inequality has a significant negative impact on relocated farmers’ sense of gain. (2) The mediation mechanism analysis reveals that individual income inequality influences sense of gain through relocated farmers’ social integration, completely through economic integration while partly through social connections and community participation. Psychological integration has a suppression effect. (3) Heterogeneity analysis shows that the above effects of individual income inequality are weaker or insignificant among relocated farmers whose family obtain educational or medical and health supports. [Conclusion] The findings indicate that the government should not only implement employment policies targeted at low-income relocated households, but also help them expand their social networks. Meanwhile, it is necessary to improve the basic public service system in the destination areas.

Considering the effects of time-varying load, time-varying excitation, longitudinal stiffness, radial stiffness and bending stiffness of each pulley, the dynamic analysis model of the inner and outer engine front-end accessory drive system is established by Simdrive software. The static characteristics of the system are evaluated. Galerkin method is used to discretize the system space, the implicit multi-step method is used to solve the dynamic characteristics of the system under acceleration conditions, and the influencing factors of the accessory pulley speed fluctuation, tension fluctuation and belt-pulley slip characteristics are obtained. Based on the analysis results, an improvement plan is proposed to appropriately increase the initial tension and the crankshaft wheel wrap angle, and add an automatic tensioner at the No.2 idler gear. The comparison analysis shows that the dynamic characteristics of the engine front-end accessory drive system are improved effectively when adding automatic tensioner.

Nickel-based superalloy is an essential material to prepare hot-end components in aero-engines and gas turbines，due to its excellent mechanical properties under high temperature. Additive manufacturing（AM） is one of the most important techniques to fabricate superalloy components with complex geometry. In this paper，the research progress of microstructure and defects of AMed superalloy is reviewed. Based on the existing literature，tensile properties of GH3536，GH3625 and GH4169 are summarized. Typical applications of AMed superalloy components in aero-engines and gas turbines are presented. Finally，for the problems in existing investigations，it is suggested that the future research can focus on materials design，heat treatment/hot isostatic pressure process optimization，single crystal preparation，real-time monitoring technique development and internal surface treatment technique innovation.

In order to clarify the microstructure of Al-Mg-Sc high-strength aluminum alloy prepared by ultra-high speed laser melting deposition，and study the relationship between structure and properties，Al-Mg-Sc high-strength aluminum alloy was prepared by using 7075 aluminum alloy as matrix and self-developed equipment（LDF3000-40 laser melting deposition machine）. The effect of laser scanning rate on the microstructure and tensile properties of the materials was investigated. The results show that there are no obvious defects such as pores and cracks in the samples deposited by ultra-high speed laser melting，but contain a few small keyholes. The samples are composed of fine α-Al equiaxial crystals and dispersed Al3（Sc，Zr）particles. The effect of scanning rate on mechanical properties is further studied by numerical simulation. It is found that the faster scanning rate of laser in the range of 0.1-1 m/s can reduce the accumulation of powder materials and porosity of the surface of the deposition layer，thus the mechanical properties can be improved. The maximum tensile strength is 303 MPa and elongation at break is 22.5%.

Recently， the analysis of animal- and plant-derived components， mainly based on the adulteration and smuggling of meat products and genetically modified crops， has been a key focus in the field of food safety. Therefore， the requirement for analytical methods has been increasingly emphasized. Recombinase isothermal amplification is a novel and promising detection technique that currently includes recombinase polymerase amplification （RPA） and recombinase-aided amplification （RAA）. This technique has been widely used in animal- and plant-derived component analysis and other detection and analysis fields owing to its speed， convenience， and high sensitivity and specificity. This paper summarizes relevant research conducted locally and abroad in recent years and concludes with an analysis of various detection methods. It also generalizes the characteristics and applications of RPA/RAA technology in four aspects： primer-probe design， external factors， reaction devices， and detection methods， and lays out the prospects for RPA/RAA development trends. Finally， this study also provides a reference for improving the analysis and detection methods of animal- and plant-derived components and promoting RPA/RAA technology.

An UPLC Quadrupole Orbitrap high resolution mass Spectrometry method for accurate quantification of aflatoxins in grains and oils was established, which were purified by automatic immunoaffinity column. The sample was extracted with 84/16(V/V) acetonitrile/water and centrifuged. The supernatant was diluted 10 times with 0.1% PBST. Aflatoxin immunoaffinity column without background and recovery greater than 90% was chosen for purification automatically. UPLC-Quadrupole Orbitrap HRMS was used for quantitative analysis. Results showed that recoveries for aflatoxins were 84.7%~104.6%. The intra-day relative standard deviations were 1.7%~9.4%, and the intra-day precision were 0.7%~8.4%. The developed method can minimize the workload, improve work efficiency and avoid the result deviation caused by operation manually. It is suitable for the accurate determination of aflatoxins in grains and oils, and meet the requirement of the daily test and monitoring aflatoxins.

Abstract Background New oral anticoagulants (NOACs) have been becoming prevalent in recent years and are increasingly used in the treatment of port vein thrombosis. The difference of the efficacy and safety between rivaroxaban and dabigatran remains unclear in the treatment of cirrhotic patients with acute portal vein thrombosis (PVT). Methods This retrospective study included all consecutive cirrhotic patients with acute portal vein thrombosis in our institute from January 2020 to December 2021. The patients received oral anticoagulation with rivaroxaban or dabigatran. The demographic, clinical, and imaging data of patients were collected. The diagnosis of acute PVT was confirmed by imaging examinations. The severity of liver cirrhosis was assessed using Child–Pugh score and Model for End-Stage Liver Disease (MELD) score. Outcomes included recanalization (complete, partial, and persistent occlusion), liver function, bleedings, and survival. The log-rank test was used to compare Kaplan–Meier distributions of time-to-event outcomes. The Cox proportional hazards model was used to calculate hazard ratios (HRs) with 95% confidence intervals (CIs). Results A total of 94 patients were included, 52 patients (55%) received rivaroxaban and 42 (45%) with dabigatran. The complete and partial recanalization of PVT was observed in 41 patients. There was no significant difference in complete recanalization, partial recanalization, and persistent occlusion between the two groups. With multivariate analysis, D-dimer (HR 1.165, 95% CI 1.036–1.311, p = 0.011) was independent predictors of complete recanalization. The Child–Pugh score (p = 0.001) was significantly improved in both two groups after anticoagulation, respectively. However, there was no difference between the two groups. The probability of survival was 94%, 95% in the rivaroxaban and dabigatran groups (log-rank p = 0.830). Major bleedings were reported in 3 patients (6%) in rivaroxaban group and 1 patient (2%) in dabigatran group (p = 0.646). Six patients (12%) in rivaroxaban group experienced minor bleeding, and five (12%) from dabigatran group (p = 0.691). Conclusions The efficacy and safety were comparable between rivaroxaban and dabigatran in the treatment of cirrhotic patients with acute portal vein thrombosis. And D-dimer can contribute to the prediction of PVT recanalization in cirrhotic patients.

Soil microbes drive soil organic carbon (SOC) mineralization. Because microbial groups differ in metabolic efficiency and respond differently to temperature variation, it is reasonable to expect a close association of SOC mineralization and its temperature sensitivity (Q10 which is defined as the factor of the change of soil carbon mineralization induced by 10 °C temperature increase) with microbial community diversity and composition. However, these relations have rarely been tested. Here, we conducted an incubation experiment to assess the temperature responses of microbial α diversity and the relative abundance of microbial r- and K-strategists in soils from a wide range of ecosystems across a climate gradient in the southeast Tibet. The results indicated that the instantaneous α diversity and the relative abundance of r- and K-strategists are significantly (P

Due to the lack of domestic 980 nm pump laser design experience and production process, the key technology of high power 980 nm pumped laser to break through. In this paper, a 980 nm pump laser with 400 mW output power has been successfully developed by using a domestic solution, including the design and implementation of chips, gratings and coupling fibers. By using the all metallized package directly coupled with wedge-shaped fiber and selecting the double grating structure for wavelength locking, the wavelength stability of the 980 nm pumped laser with 400 mW output power in the operating temperature range of -50~75 ℃ can reach 0.01 nm/ ℃. Moreover the 980 nm pump laser has passed the 800 mA charge aging at 75 ℃ for more than 5 000 h. This has laid a foundation for the research of domestic pump lasers with high reliability.

Abstract Background Primary gastrointestinal natural killer (NK)/T‐cell lymphoma (PGINKTL) is a rare T‐/NK‐cell lymphoma subtype, and the clinical features and survival outcomes remain largely unknown. Methods To summarize the clinical features and survival outcomes of PGINKTL, PGINKTL cases diagnosed at our hospital from May 1999 to December 2020 were reviewed; and the clinical data, information on treatment strategies, and survival were collected. Survival analysis was performed using the Kaplan–Meier method and multivariable Cox proportional hazards regression. We constructed a nomogram to visualize the survival prediction of PGINKTL. The discriminative ability and calibration of the nomogram for prediction were tested using the concordance index (C‐index) and calibration plots. Results The cohort included 81 cases, the median age was 36 years (range, 7–80 years), and the male‐to‐female ratio was 1.7:1. The most common clinical symptom at the time of diagnosis was abdominal pain (71.6%). The most common lesion site was the colon (59.3%). During a median follow‐up period of 37.7 months, the median overall survival (OS) time of 81 patients was 4.0 months (95% confidence interval [CI], 3.1–4.9 months), and the 2‐year OS rate was 30.7% (95% CI, 20.3%–40.1%). The multivariate analyses indicated that patients with an Eastern Cooperative Oncology Group (ECOG) performance status (PS) score ≥2, serum lactic dehydrogenase (LDH) level ≥ the upper limit normal (ULN), and perforation had worse OS. We used these data to establish a nomogram to predict survival for PGINKTL. The nomogram displayed good accuracy, with a C‐index of 0.726. Conclusion The clinical features and poor outcomes of PGINKTL, which is a rare and fatal lymphoma type, are presented. The proposed nomogram provides an individualized estimate of survival for these patients. In the future, the study focused on exploring a better treatment strategy to improve survival is required in PGINKTL.

[Objective] The characteristics of surface soil soluble organic carbon (DOC), readily oxidized organic carbon (ROC), carbon pool stability, and carbon storage changes, as well as influencing factors of soil organic carbon (SOC) and DOC at different elevations in Tibetan Plateau were analyzed in order to provide a scientific basis for subsequent research on the stability of SOC in cold regions with complex terrain. [Methods] Data were collected from a rocky beach of the Sejila Mountain. One-way ANOVA was used to analyze soil physical properties and DOC, ROC, and SOC content characteristics at altitudes ranging from 4 300 m to 4 700 m. Pearson correlation analysis and redundancy analysis were used to determine the relationship between DOC, ROC, and influencing factors. [Results] ① Soil bulk density and dry density were negatively correlated with altitude, and their maximum values were 1.56 g/cm3 and 1.12 g/cm3, respectively. Soil water content and porosity were positively correlated with altitude, and the maximum values were 74.22% and 58.70%, respectively. ② SOC content initially increased with increasing altitude and then decreased. DOC and ROC showed fluctuating trends with elevation. ③ DOC/SOC and ROC/SOC reached maximum values at 4 400 m. The average DOC and SOC values were 40.779 kg/m2 and 8.105 kg/m2, respectively. The stability of the soil carbon pool in the rocky beach area was relatively good. ④ DOC had no correlation with soil physical properties, but was correlated with average SOC. ROC was correlated with physical properties, SOC, and its related factors. Each factor was correlated with changes in DOC and ROC in the rocky beach area of the Sejila Mountains. Explanatory contribution rate follow the order of average DOC>soil porosity>ROC/SOC>soil water content>SOC>average SOC>DOC/SOC>soil dry density. [Conclusion] Soil DOC and ROC at different elevations were correlated, and average DOC, soil porosity, and ROC/SOC were important factors affecting the contents of DOC and ROC. There were close relationships among these factors.

Aiming at the typical five-hole structure on the aircraft skin, combined with the failure criterion of multi crack structure and considering the random factors affecting the residual life distribution of multiple crack structure, this paper applies the branch and bound algorithm to the screening of the main failure modes of typical five-hole structure, and gives the specific screening steps. The residual life of the structure is predicted by Franc3D crack propagation software, and the life interference model is established. Finally, the residual life distribution curve of the five-hole structure is formed to complete the screening of its main failure modes. The results show that the efficiency of using the algorithm to screen the main failure modes of the structure has been improved by 77.2%, and the error between the corresponding median life and that before screening is about 12%, indicating that the result of screening the main failure modes of the structure by the algorithm is more accurate. Compared with the existing test results, the median life predicted by the life distribution is more conservative and has certain reliability and accuracy. This method has certain reference significance for the evaluation of the safe life of this multi-holes structure.

To optimize soil health, land use, and soil management decisions need to be guided by an understanding of the underlying soil health. Although widely used fertilizers guarantee crop production, they ultimately damage agricultural soil environmental quality and threaten the overall food chain safety. Thus, an integrative assessment considering both environmental safety and soil fertility is required for the sustainable development of long-term fertilization systems. In this study, we conducted a comprehensive assessment of soil health using 20 soil physical, chemical, and biological indicators and assessed them according to four heavy metals—copper, zinc, cadmium, and lead. This experiment was conducted in an area where there is an ongoing, 23-year-long fertilization experiment in a typical red soil region of southern China, including four treatments of common inorganic chemical fertilizer (CF), CF mixed with micronutrients (CF + T), CF mixed with pig manure (PM), and PM mixed with micronutrients (PM + T). To assess the soil fertility quality, we selected a minimum data set consisting of soil water-stable aggregates mean weight diameter, available phosphorus, total nitrogen, microbial biomass carbon, and dehydrogenase activity. The results revealed that soil fertility quality followed the order of PM + T ≈ PM > CF + T > CF. We also used a modified potential ecological risk index to assess the soil environmental quality. This approach considered the acid-soluble and exchangeable fraction of heavy metals as the bioavailability component. Both PM and PM + T treated soils were significantly contaminated by heavy metals, with particularly large amounts of Cd contamination. The soil health index escalated from CF, CF + T, PM to PM + T, which indicated that the use of pig manure allowed for more fertile soil relative to standard chemical fertilization. Moreover, applying additional micronutrients also had a significant influence on soil fertility. Therefore, our study revealed that long-term fertilization using organic pig manure was beneficial to overall soil fertility; however, these benefits were coupled with significant limitations regarding heavy metal contamination. Collectively, this study provides a better supporting method for soil health management and long-term fertilization strategies.

Abstract The vulnerability of the current network has become an urgent problem to be solved. The focus of network protection should be shifted from traditional network protection to the direction of effective recovery even after being attacked and damaged, and then, the concept of resilience came into being. This paper selects physical explosion attacks to establish damaged network. An improved system resilience recovery strategy is established which considers task importance and time efficiency. Aiming at the initial population is too random, easy to mature and with poor solution, this paper improves genetic algorithm by new greedy model in population initialization and head-to-head mutation operator. Simulation shows that the improved genetic algorithm is better and more stable, the improved quotient model is more effective in system resilience recovery measured by index-E proposed in this paper.

Abstract An enriched environment (EE) is a promising strategy for protecting the intestinal mucosal barrier and regulating the brain-gut axis, but the optimal EE intervention duration is unknown. Here, different EE intervention durations were applied to assess the optimal intervention duration in rats with colorectal cancer. We used a rat model of 1, 2-dimethylhydrazine-induced colorectal cancer. The rats were housed in an EE for 0, 2, 4, 8 weeks and 8-week blank group. The intestinal mucosa and serum TNF-α, IL-6, IL-10, ATP, CRF, and occludin levels and bacterial translocation (BT) were measured, and the intestinal mucosa morphology was evaluated. In 8 weeks, the effect of tumor on intestinal mucosal barrier was not obvious and the EE had a greater impact on it. Eight weeks of EE was more beneficial to the intestinal mucosal mechanical barrier than 2 or 4 weeks of intervention. A significant difference in BT was found between the 4- and 8-week groups. Overall, the analysis of inflammatory factor regulation revealed that the two blank groups exhibited the worst effect, and the intervention effect at 8 weeks was better than that at 2 and 4 weeks. CRF at 4 weeks was higher than that at 8-week blank group. The effect of 8-week intervention duration on the intestinal mucosal barrier was generally better than that of 2- and 4-week durations and intervention within 4 weeks can help to stabilize and promote the secretion of brain gut peptide, but the effect of different intervention durations on the brain-gut peptide levels was not obvious. In the future, we can further explore the molecular biological mechanism of the effect of different EE intervention durations on the intestinal mucosal barrier and analyze the effect of an EE on other brain-gut peptides.

The main functional components and biological activities of Grifola frondosa were reviewed, and the existing problems and future research directions were also discussed.

Numerous studies indicated that B vitamin supplementation can reduce cardiovascular risk; nonetheless, available proof reported from individual studies have not been consistent, so we performed an updated meta-analysis of randomized controlled trials (RCTs) to evaluate the relationship between B vitamin supplementation and cardiovascular outcomes.

Objective To investigate the protective effect of idebenone (IDBN) on hippocampal neuron injury in epileptic rats and its mechanism. Methods Forty-eight Wistar rats were randomly divided into normal control group, IDBN prevention group (prevention group), epilepsy group, IDBN 25, 50 and 100 mg groups. Behavioral changes of rats in different treatment groups before and after treatment with IDBN were observed. The activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) and the content of malondialdehyde (MDA) in hippocampal were detected. The ultrastructural changes of hippocampal neurons and mitochondria were observed. Results The expression levels of SOD, GSH-Px and MDA in different treatment groups were significantly different (P = 0.000, for all). The activity of SOD and GSH-Px was the highest and the content of MDA was the lowest in IDBN 100 mg group. The activity of SOD and GSH-Px in IDBN 100 mg group were higher than those in epilepsy group (P = 0.000, 0.000), IDBN 25 mg group (P = 0.000, 0.000) and 50 mg group (P = 0.004, 0.005), while the content of MDA was lower than that in epilepsy group (P = 0.000), IDBN 25 mg group (P = 0.000) and 50 mg group (P = 0.002). Compared with normal control group and prevention group, hippocampal neurons in epilepsy group showed different degrees of damage, which was relieved after treatment with IDBN and gradually decreased with the increase of dose. In epilepsy group, the mitochondrial structure of hippocampal neurons was damaged obviously, with deformation and swelling, and some mitochondria were vacuolated. After treatment with IDBN, the damage was relieved, and the 100 mg group had the least damage. Conclusions IDBN can protect hippocampal neuron structure and function by inhibiting oxidative stress injury in epileptic rats.

Since the beginning of the COVID-19 epidemic, the pathogen of COVID-19, SARS-CoV-2, has evolved and mutated continuously, producing variants with different enhanced transmission and virulence, such as Alpha (B.1.1.7) , Beta (B.1.351) , Gamma (P.1) , Delta (B.1.617.2) and Omicron (B.1.1.529) . An intensive study of the incubation period of COVID-19 caused by different SARS-CoV-2 variants will contribute to tracing the origin of COVID-19, determining the detention, quarantine and isolation time of close contacts, and timely improving measures for containing COVID-19. We reviewed the major studies on the incubation period of COVID-19 caused by wild-type strains and different variants of SARS-CoV-2, which estimated that the incubation period of COVID-19 caused by wild-type SARS-CoV-2 strains was 4-8 (median 5.5) days. And that for COVID-19 caused by Beta or Gamma variant was generally similar to that by wild-type strains, about 5 days. The incubation period of COVID-19 caused by Alpha, Delta and Omicron variants was shorter than that of other strains, which was 4, 4 and 3 days, respectively.

Large-scale high-dimensional unbalanced data handling is a major challenge in anomaly detection.One-class support vector machine(OCSVM) is very efficient at handling unbalanced data,but it is not suitable for large-scale high-dimensional dataset.Meanwhile,the kernel function of OCSVM also has an important influence on the detection performance.An anomaly detection model combining a deep auto-encoder and a one-class support vector machine is proposed.The deep auto-encoder is not only responsible for extracting features and dimensionality reduction,but also mapping an adaptive kernel function.As a whole,the model adopts the gradient descent method to carry out joint training and realizes end-to-end training.Experiment is conducted on four public datasets and compared with other anomaly detection methods.Experimental results show that the proposed model has better performance than single-kernel or multi-kernel one-class support vector machines and other models in terms of AUC and RECALL,and the proposed model is robust at different anomaly rate and has great advantages in time complexity.

【Objective】The spatial heterogeneity of alpine ecosystems in southeastern Tibet in the vertical distribution zone was analyzed, and the distribution characteristics and influencing factors of soil organic carbon(SOC)reserves at different altitudes were studied.【Methods】Taking the Sejila Mountain, a typical mountain in southeastern Tibet in the alpine and semi-humid region, as the research object, sampling was carried out at an altitude of 3 400-4 600 m with an altitude gradient of 200 m, and the altitude was investigated by combining field investigation and indoor analysis. The impact of altitude on the vertical distribution characteristics of SOC and its correlation with other physical and chemical indicators.【Result】There was a great spatial heterogeneity among the soil physical indexes in the Sejila Mountain at an altitude of 3 400~4 600 m. The soil bulk density, total porosity, capillary porosity and non-capillary porosity varied 0.72-1.08 g/cm3, 51.76%-67.06%, 47.11%-58.03% and 9.03%-11.04%. SOC was mainly distributed in the 0-60 cm soil layer, and the SOC contents of different altitude gradients(1.57%-8.24%)showed a downward trend with the increase of soil depth, and the SOC content of the alpine meadow at an altitude of 4 618 m was the highest, which was 1.76-3.07 times that of other altitudes; SOC reserve was 117.14-220.63 t/hm2, among which the SOC reserve in the soil layer at an altitude of 4 255 m was significantly higher than that at other altitudes, equivalent to 2 times that at an altitude of 3 393 m; different altitudes significantly affected the SOC reserves in the 0-60 cm soil layer, showing a single peak as a whole curve change trend.【Conclusion】There are significant differences in the vertical distribution of SOC under different vegetation types in the Sejila Mountain, and the change of altitude gradient will directly or indirectly affects the accurate estimation of SOC, and then affects the spatial distribution and prediction of SOC.

Since the first case of the Omicron (B.1.1.529) variant discovered in South Africa was reported to the WHO on November 24, 2021, a total of 57 countries (regions) had reported Omicron cases as of December 8, 2021. Omicron has become the dominant strain in some African countries and is spreading rapidly. Although Omicron causes mild symptoms, with most cases being asymptomatic and mild, the rapid increase in the number of cases could put a heavy strain on global health systems. In addition, its source, transmission characteristics and vaccine resistance remain unclear, which brings great challenges to pandemic prevention and control in all countries (regions) . We reviewed the latest developments in etiological characteristics, mutation sources, transmission characteristics and possible mechanisms, pandemic status, vaccine protection effect and containment measures regarding Omicron, providing a reference for scientific containment of Omicron mutant.

Objective To explore the incidence of pain flare (PF) in spine metastasis stereotactic body radiotherapy (SBRT) or hypofractionated radiotherapy (HF) and the prophylactical effect of dexamethasone. Methods Sixty-five patients were treated with spine metastasis SBRT and randomly divided into control group (SBRT or HF, n=32) and treatment group (SBRT or HF and 4.5 mg dexamethasone, n=33). The brief pain inventory (BPI) was used to score the pain before, during and after treatment. PF was recorded and compared between two groups. Results The incidence of PF was 24.6% in all patients (control group: 37.5%, treatment group: 12.1%, P=0.018). PF in both group occurred in d1-2, accounting for 62.5% in all PF (control group: 66.7%, treatment group: 50%, P=0.551). The incidences of PF in control group were 66.7% and 33.3% for three and ten fractions scheme, respectively (P=0.001). However, the incidences of PF in treatment group were 50% and 50% for three and ten fractions scheme, respectively (P=0.643). Conclusion Oral dexamethasone has an excellent efficacy in prevention and treatment of PF in spine metastasis SBRT or HF, with significantly decreased incidence of PF. A phase Ⅲ clinical trial is required to finalize the optimal dose and schedule.

With the rapid progress of natural language processing techniques and the massive accessible conversational data on Internet,non-tasked oriented dialogue systems,also referred to as Chatbots,have achieved great success,and drawn attention from both academia and industry.Currently,there are two lines in chatbots research,retrieval-based chatbots and generation-based chatbots.Due to the fluent responses and low latency,retrieval-based chatbots is a common method in practice.This paperfirst briefly introduces the research background, basic structure and component modules of retrieval-based chatbots,and then illustrates the constraints of the response selection module and related data set in details.Subsequently,we summarize recent popular techniques for response selection problem,including:statistic method,representation-based neural network method,interaction-based neural network method,and pre-training-based method.Finally,we pose the challenges of chatbots and outline promising directions as future work.

Objective: To establish an analytical method for the determination of four main flavor substances in liquor. Methods: A gas chromatography mass spectrometry （GC-MS） method was established for the simultaneous determination of esters, alcohols, acids, and aldehydes in liquor. Single ion monitoring （SIM） mode was chosen. Then the method was inspected through comparison with the standard mass spectrum database, quantitative analysis of the external standard method and relative standard deviation of day-in and day-out were investigated. Results: The limits of detection of the four types of flavor compounds in liquor were 0.007~0.070 mg/L, and the limits of quantitation were 0.020~0.200 mg/L, and the linearities were satisfactory in the range of 0.000 5~5.0 g/L, with the correlation coefficients of R2≥0.998 5. The accuracy was tested by adding three levels of low, medium and high concentrations of standard substances to ethanol in water （60%）, and the average recoveries of the four categories of flavor substances were 87.8%~107.4%, with the relative standard deviations （RSDs） of 2.0%~7.4% （n=6）. Conclusion: The method is accurate and reliable, with good repeatability and high sensitivity. The method is stable and can be used for the determination of various trace substances in wine. It was found that the volatile flavor compounds of different flavor liquors were different to some extent, which could provide a reference for further research on the flavor compounds of liquor.

BackgroundAs a fundamental property of peptide molecules, chirality has been demonstrated to play an important role in controlling the structures and characteristics of peptide supramolecular systems. However, the mechanism through which chirality takes effect has not been clarified.PurposeThis study aims to examine the self- and co-assembled nanostructures and analyze the intermolecular interactions that drive the assembly by employing diphenylalanine (FF), along with the core recognition sequence of Amyloid-β protein (Aβ) and its enantiomer D-Phe-D-Phe (ff), in a model system.MethodsA series of structural and morphological analyses were conducted in the experiments. First, the scanning electron microscopy (SEM) and atomic force microscopy (AFM) images of the assembled nanostructures were obtained to observe the microscopic morphology and topological structure of the assembled FF and ff. Subsequently, circular dichroism (CD) and Fourier transform infrared spectroscopy (FTIR) were employed to characterize the secondary structures of peptides in the nanostructures. Finally, fluorescence emission spectrum and X-ray diffraction (XRD) analyses revealed the intermolecular interactions between peptide and solvent molecules.ResultsThe findings demonstrate that FF and ff self-assemble into similar fibrous nanostructures, and their chirality primarily affects the interactions between peptide molecules, as well as those between peptide and water molecules. Furthermore, the formation of new crystalline phases for the co-assembly of FF and ff was confirmed by XRD.ConclusionsOur results may facilitate the understanding of the formation mechanism of amyloid fibers and design of peptide supramolecular materials.

With the rapid development of packaging industry and the improvement of environmental protection requirements of human society, biodegradable functional packaging film materials have attracted great attention. However, commercial biodegradable functional package film materials have been constrained by its high cost, low mechanical properties and water resistance. The lignin microspheres were firstly prepared by self-assembling and were adhered to the surface of cellulose film via self-depositing, resulting in fabrication of novel cellulose-based UV-blocking film materials. Subsequently, the surface morphology, ultraviolet resistance and mechanical properties of the obtained functional film materials were studied. The surface properties of films were investigated by scanning microscopy (SEM),infrared spectroscopy (FTIR) and confocal laser scanning microscopy.The mechanical properties and UV resistance of cellulose based films were characterized by tensile test and UV transmittance test.It is noteworthy that the lignin microspheres with 1-2 μm in size are uniformly distributed on cellulose films and hydrophobic modification of cellulose-based films facilitated the deposition of lignin. Moreover, the deposited contents of lignin microspheres increase with the increase of the lignin concentration in solution. Due to the introduction of lignin microspheres, the strength of cellulose composites film increases by 22% and the UVB-shielding capacity reaches 94% as compared with the controlled cellulose films.

For the high demand for cement-based materials in buildings, improving the performance of cement-based materials has become the focus of relevant researchers. In recent years, nanomaterials have broad prospects in many fields such as architecture by virtue of their “lightweight, high strength, and strong solidity” characteristics. As a modifier of cement-based materials, it has also become a research hotspot. Graphene oxide (GO) is one of the most representative graphene-based nanomaterials. Because of its extremely high specific surface area and excellent physical properties, it has greatly improved the properties of cement-based materials. GO acts as an enhancer of cement composites that brings people unlimited imagination. The research progress of GO-modified cement-based materials is reviewed. The purpose is to point out the limitations of current research and provide a reference for later research. The dispersion treatment of GO and the properties of its modified cement-based materials are analyzed and summarized. In addition, the further research work that is needed and future development prospect are discussed.