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In order to optimize the fermentation process conditions of mulberry leaf tea and explore the changes in antioxidant activity of mulberry leaf tea after fermentation. This experiment used response surface analysis to determine the optimal process conditions for fermenting mulberry leaf tea under three variable conditions: Fermentation temperature, fermentation time, and inoculation amount of Aspergillus niger. The content of bioactive substances and antioxidant properties in fermented mulberry leaf tea were determinated. The findings indicated that 5 days and 16 hours of fermentation duration, 30 ℃ of fermentation temperature, and 16.55% of inoculation amount were the ideal process parameters, and that the fermented mulberry leaf tea scored as high as 90 on the sensory scale under these conditions. In addition, the content of total flavonoids, total polysaccharides, polyphenols, free amino acids, rutin, and quercetin in fermented mulberry leaf tea increased by 14.39%, 12.67%, 2.90%, 3.46%, 81.13%, and 19.35%, respectively, compared to mulberry leaf green tea. Tea brown pigment with a content of 7.55%±0.37% was also detected in fermented mulberry leaf tea. In addition, the scavenging rate of hydroxyl radicals, DPPH radicals, superoxide radicals and the chelating rate of divalent iron ions of fermented mulberry leaf tea at the concentration of 1/1000 (g/mL) were 1.16, 1.07, 1.06 and 0.82 times higher than that of mulberry leaf green tea, respectively. The results of this study provide theoretical basis and references for further development and application of mulberry leaf in the future.

In order to sort out the research process and hotspots of honey safety, this paper was based on the China national knowledge infrastructure (CNKI) database and the Web of Science (WOS) core collection, utilizing CiteSpace software to analyze and visualize publication trends, journals, authors, institutions, countries (regions), keywords, and other relevant information. The aforementioned databases yielded a total of 169 Chinese and 281 English literatures. The analysis revealed that the number of publications in Chinese literature on honey safety had been steadily increasing since 2011. The number of publications in English literature had displayed an oscillating upward trend since 2007, with a higher volume of publications in English literature over the past fifteen years compared to Chinese literature. ZHANG Q and GUNDUZ A were the most prolific authors in Chinese and English literature, respectively. While there were established cooperative relationships between researchers in both fields, collaborations between different groups remained relatively limited. Journal of Bee and Food Chemistry were the leading journals for publications on honey safety in English and Chinese, respectively. Both English and Chinese publishing journals primarily focused on the food industry. Yunnan Province Center for Disease Control and Prevention and Karadeniz Technical University were the research institutions with the highest publication output in Chinese and English, respectively. However, there was limited collaboration between research institutes in China. Turkey was the most influential country among the study countries (regions), followed by China, Poland, and New Zealand. During the initial stages of research, Chinese literature primarily explored topics such as "botulinum toxin" "pollen plants" "Triperygium wilfordii Hook. f." and "honey poisoning". However, after 2000, advancements in technologies such as chromatography, spectroscopy, and scanning electron microscopy led to the emergence of new keywords like "melissopalynology" and "gas chromatography". Consequently, gas chromatography, liquid chromatography, liquid-mass spectrometry, and scanning electron microscopy gained popularity as methods for detecting honey safety in research. During the early stages of research, English literature primarily delved into topics such as "pyrrolizidine alkaloids" "mad honey" "grayanotoxin" and "natural toxicants". This indicates that during this time, the primary emphasis was on studying toxic honey and natural toxins found in honey, specifically pyrrolizidine alkaloids and grayanotoxin. As technologies such as chromatography advanced, keywords like "mass spectrometry" began to emerge. It could be seen that the research in Chinese and English literature was focused on similar topics, such as toxic honey, honey poisoning, and the detection and tracing of toxic components in honey. However, there were slight differences in emphasis. In China, the main toxic nectar plants were Triperygium wilfordii Hook. f., Gelsemium elegans (Gardn. & Champ.) Benth. and Macleaya cordata (Willd.) R. Br., while the main toxic components detected in honey were triptolide and koumine. In foreign countries, honey poisoning incidents were mostly caused by grayanotoxin, pyrrolizidine alkaloids or tutin. This study provides reference for analyzing the research content and development process of honey safety and identifying research hotspots.

To optimize the resource utilization of walnut green husk and investigate the impact of grinding treatment on walnut green husk powder, this experiment was carried out to investigate the physical characteristics (particle size distribution, filling, flowability, water-holding capacity, oil-holding capacity, swelling capacity, and microstructure) and functional characteristics (active substance content, and antioxidant activity) in walnut green husk powders with varying particle sizes. The results demonstrated that the particle size of walnut green husk powder exhibited a significant difference (P

In order to study the effective method of the enrichment and purification of anthocyanin in black wolfberry and mulberry, and identify the structure of anthocyanin, the black wolfberry and mulberry extracts were purified by macroporous resins. The adsorption and desorption abilities of different types of the resins for anthocyanins were compared. LX-20SS was optimized as the resin for the purification of anthocyanins from black wolfberry. The purification conditions were as follows: The mass ratio of resin to crude anthocyanin powder of black wolfberry was at 10:1, and the elution concentration of ethanol was 70%, and the flow rate was 3 mL/min. After the purification, the content of anthocyanin reached 144.18±3.40 mg/g. DM-21 was optimized as the resin for the purification of mulberry anthocyanin. The purification conditions were as follows: The mass ratio of resin to crude anthocyanin powder of mulberry was at 20:3, and the elution concentration of ethanol was 30%, and the flow rate was 1 mL/min. The content of anthocyanin reached 112.44±2.24 mg/g after purification. High performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) analysis for anthocyanin structures in black wolfberry and mulberry showed that the main anthocyanin in black wolfberry was petunidin-3-O-rutinose (p-coumaroyl)-5-O-glucoside, which accounted for more than 95% of the total anthocyanin. In addition, there are two main types of anthocyanins in mulberry, corresponding to cyanidin-3-glucoside and cyanidin-3-rutinoside, which accounted for 63.58% and 36.42% of the total anthocyanins respectively. The results provided references for the development of black wolfberry and mulberry.

The occurrence mechanism of coal and gas outburst disasters is still unclear. According to the rheological hypothesis, gas-bearing coal and rock may enter the “strength limit neighborhood” under long-term load, and it is more likely to be destroyed by external impact disturbance. The “strength limit neighborhood” of gas-bearing coal rock under different loading conditions is studied to find the influence law of entering this state, and the corresponding micro-discrimination criteria are established,” using the self-developed triaxial test system of rock rheological disturbance effect and the seepage experimental device of coal rock rheological disturbance effect, the rheological disturbance experiment of gas-bearing coal rock under different confining pressures, different gas pressures and axial pressures was carried out. The coal rock before and after rheological disturbance was analyzed and compared by means of nuclear magnetic resonance, and the T2 spectrum curve, porosity and pore size distribution under different loading conditions were obtained. The test results show that: ① In the rheological process of coal rock under different loading conditions, there is a critical value for the sensitivity of external disturbance. When the applied force is less than this critical value, after the impact disturbance, the porosity of coal rock decreases and the specimen is compressed closely. When the force is greater than this critical value, after the impact disturbance, the large pore size of coal rock increases obviously, the T2 spectrum curve shifts to the right, and the peak height increases, It shows that the stress threshold is the key to determine whether the coal rock enters the “strength limit neighborhood”. ② Confining pressure and gas pressure have opposite mechanical properties to coal rock. It is shown in the compressive capacity, damage degree, long-term strength and “strength limit neighborhood”. Among them, the greater the confining pressure, the earlier the coal rock enters the “strength limit neighborhood;” The greater the gas pressure, The greater the gas pressure, the earlier the coal rock enters the neighborhood. ③ the pore size distribution and T2 spectrum curve of coal rock can directly reflect the internal and external micro-variation characteristics of rock’s “strength limit neighborhood.” ④The constitutive equation of axial pressure, confining pressure and gas pressure determined by the porosity of coal rock can be used to judge the timing of coal rock entering the “strength limit neighborhood” under different loading conditions. As a criterion for entering the “strength limit neighborhood,” the greater the confining pressure, the greater the stress threshold when entering the “strength limit neighborhood,” the greater the gas pressure, and the smaller the stress threshold when entering the “strength limit neighborhood.”

ObjectiveThe study in this paper aims to investigate the impacts of cabin atmosphere quality on the comfort and the work efficiency of crew member aboard the ship, thereby the degree of thermal comfort of ship air conditioning system can be improved.MethodAirpak software is used to simulate and analyze the temperature, relative humidity, PMV-PPD and air age in the four air supply and return modes of a typical single-occupant cabin of a ship, namely ‘different side up and down cycles’, ‘same side up and down cycles’, ‘different side down and up cycles’, and ‘same side down and up cycles’. ResultsThe simulation results show that the temperature in the cabin can be kept constant at 24℃, humidity can be maintained at about 50% and the humidity field distribution can be more uniform, while PMV (predicted mean vote) distribution is more uniform with its value tending to zero, and the air age PPD (predicted percentage of dissatisfied) distribution is more uniform with a very low value in the cabin.ConclusionUsing the optimization principle of lattice order theory, the air supply and return mode of ‘different side up and down cycles’ is the optimal scheme for a single-occupant cabin of a ship.

Starch was the main source of carbohydrates in people's daily diet, and its digestibility was an important factor affecting the body's postprandial blood glucose level. In this paper, the effect of xylose on the in vitro digestive properties of corn starch and its mechanism of action were investigated. The in vitro digestibility of starch was evaluated by an in vitro simulated digestion system after different additions of xylose (5%, 10%, and 15%), and the mechanisms of xylose on α-amylase and α-glucosidase, as well as its effect on blood glucose fluctuation through enzyme inhibition kinetics, molecular docking, and human glycemic index (GI) tests. The results showed that the digestive hydrolysis of corn starch was inhibited by different amounts of xylose, and the IC50 values of xylose on α-glucosidase and α-amylase were 205.35 and 4.75 mg/mL, respectively, which belonged to the mixed type inhibitors. Xylose interacted with amino acid residues of α-glucosidase and α-amylase through hydrogen bonding with binding energies of −3.05 and −5.30 kcal/mol, respectively. Additionally, the GI value of plant-based peptidoglycan milk decreased from 58 to 45 after the addition of xylose, which demonstrated that xylose was effective in decreasing the fluctuation of postprandial blood glucose. The results could provide scientific data to support the research and application of xylose in nutritional and health foods.

Background The heterogeneity of myelodysplastic syndromes (MDS) is strong, with poor efficacy of existing therapeutic regimens and large individual differences in patient prognosis. B-cell lymphomato-2 (Bcl-2) protein is highly expressed in patients with myeloid tumors, which has been proved by previous to be associated with disease progression, chemotherapy resistance, and shortened overall survival. The Bcl-2 inhibitor Veneckla (VEN) is approved for elderly patients with newly diagnosed acute myeloid leukemia (AML) who are not eligible for intensive therapy, and there is less data on its use in MDS patients. The difference in Bcl-2 expression in MDS patients and its correlation with the efficacy and prognosis of VEN therapy haven't been reported. Objective To analyse the expression of Bcl-2 protein in MDS patients and assess its correlation with the efficacy and prognosis of VEN treatment. Methods The clinical data of 71 patients with MDS admitted to Sichuan Academy of Medical Sciences·Sichuan Provincial People's Hospital from July 2018 to December 2022 were retrospectively analyzed. Baseline data of patients including gender, age, blood routine, blood biochemistry, bone marrow hemocytology, flow cytometry, chromosome karyotype, myeloid gene mutation, fusion gene mutation and MDS-EB typing were collected. The expression of Bcl-2 protein was detected by immunohistochemical staining. According to the modified International Prognostic Score System (IPSS-R), the patients were divided into 5 risk levels of very low risk (0 case), low risk (1 case), medium risk (7 cases), high risk (40 cases) and very high risk (23 cases). Patients with bone marrow Bcl-2 positivity≥10% were defined as Bcl-2 positive and0.05) . Conclusion Bcl-2 protein contributes to MDS fusion gene mutation and myeloid gene mutation; Bcl-2 positive expression was not associated with the survival of MDS patients. There was no difference in survival rate between Bcl-2 positive and Bcl-2 negative patients who received the VA combination regimen.

Background Cardiovascular disease (CVD) is the leading cause of death in China and the world as a whole, and lipid metabolism disorder is the key factor for this disease. A comprehensive understanding of the prevalence of dyslipidemia in children and adolescents can contribute to the early prevention of dyslipidemia in adulthood. Objective To systematically evaluate the status quo of the prevalence of dyslipidemia in Chinese children and adolescents. Methods Cross-sectional studies on the morbidity rate of dyslipidemia among Chinese children and adolescents and published from January 2015 to July 2023 were retrieved from databases of CBM, CNKI, Wanfang, VIP, Embase, Web of Science and Cochrane Library. Processes of literature screening, data extraction and risk bias analysis were performed by two researchers. A meta-analysis was performed by taking advantage of Stata 17.0. Results 34 cross-sectional studies were collected and a total of 134 438 children and adolescents were involved. Results of the meta-analysis indicated that the overall morbidity rate of dyslipidemia in Chinese children and adolescents was 19% (95%CI=16%-21%), and the morbidity rates of high cholesterol (TC), high triacylglycerol (TG), high low-density lipoprotein cholesterol (LDL-C), low high-density lipoprotein cholesterol (HDL-C) were 6% (95%CI=5%-7%), 9% (95%CI=6%-12%), 4% (95%CI=3%-5%) and 10% (95%CI=7%-13%) respectively. Regarding time distribution, the detection rate of dyslipidemia was fluctuant and showed a decreasing trend; the detection rate of high TC and high LDL-C showed an increasing trend in general, but it fell slightly in 2023; the detection rate of high TG and low HDL-C fluctuated greatly: the detection rate of high TG gradually decreased from 2018 to 2022 and rebounded slightly in 2023. The results of subgroup analysis showed that, concerning age, the overall morbidity rate of dyslipidemia in children and adolescents and that of high TC showed an ascending tendency with the increasing of age (10% and 2% for those aged from 3 to 6, 17% and 10% for those aged from 7 to 11, and 27% and 14% for those aged from 12 to18), the morbidity rate of lowered HDL-C was higher among 12-to-18-year olds (20%) than among 7-to-11-year olds (9%), and the morbidity rate of high TC among 3-to-6-year olds (9%) was higher than that among 7-to-11-year olds and 12-to-18-year-olds (4% and 3%) (P

Background Rifampicin-resistant/multidrug-resistant tuberculosis (RR/MDR-TB) is featured by challenges in the treatment, low cure rate, and high infectivity. Fluoroquinolones (FQs), as the core drugs for the treatment of RR/MDR-TB, have a severe trend of resistance. Analyzing influencing factors for FQs can help to increase the cure rate of RR/MDR-TB and to control the occurrence of the pre-extensive drug resistance (pre-XDR) and extensive drug resistance. Objective To analyze the drug resistance of FQs in hospitalized patients with pulmonary tuberculosis and the influencing factors, and to construct and validate a Nomogram prediction model for the risk factors of drug resistance of FQs. Methods A total of 583 patients with pulmonary tuberculosis who were hospitalized in Guiyang Public Health Clinical Center from January 2021 to February 2022 and tested for drug sensitivity were retrospectively selected as study subjects. They were divided into the initial treatment group (296 patients) and the retreatment group (287 patients) according to the history of previous treatment. Moreover, they were divided into the FQs-resistant group (63 patients) and FQs-sensitive group (520 patients) according to their FQs-resistance status. The distribution of total resistance to 13 antituberculosis drugs in 583 patients was analyzed, and the baseline characteristics of patients in the FQs-resistant group and FQs-sensitive group were compared. After screening the characteristic variables using least absolute shrinkage and selection operator (LASSO) regression model, multivariate Logistic regression was performed to analyze the independent risk factors for the resistance of FQs. A Nomogram prediction model was constructed, and its performance was validated by calculating the area under the curve (AUC) of receiver operating characteristic (ROC), and plotting the calibration curve. Results Among 583 patients, 520 cases were sensitive to FQs and 63 cases were resistant (resistance rate of 10.81%). The resistance rate of FQs was secondary to the total resistance rate of first-line antituberculosis drugs, including the isoniazid (36.36%), rifampicin (32.76%), streptomycin (21.61%), and ethambutol (12.86%). The resistance rates of rifampicin, isoniazid, ethambutol, streptomycin, levofloxacin, moxifloxacin and rifampicin resistance (RR), multidrug resistance (MDR), and pre-XDR were significantly higher in patients of the retreatment group than those of the initial treatment group (P

目的 本研究对烟雾病患者血管样本的差异表达基因（differentially expressed genes，DEGs）进行生物信息学鉴定和分析，旨在探讨烟雾病的潜在发病机制。 方法 本研究以烟雾病和颈内动脉瘤患者大脑血管样本为研究对象。利用R语言线性模型微阵列数据（linear models for microarray data，limma）分析包对基因表达综合数据库（gene expression omnibus，GEO）中的GSE141025数据集进行分析，该数据集涵盖4例烟雾病患者和4例颈内动脉瘤患者的大脑中动脉和颞浅动脉样本各1个，共计16个样本。选择烟雾病患者的大脑中动脉、颞浅动脉及颈内动脉瘤患者的颞浅动脉共12个样本进行DEGs筛选。通过R语言功能富集分析工具包clusterProfiler，对筛选出的DEGs进行基因本体（gene ontology，GO）富集分析和京都基因与基因组百科全书（Kyoto encyclopedia of genes and genomes，KEGG）通路分析。利用STRING数据库构建蛋白质-蛋白质相互作用（protein-protein interaction，PPI）网络，并使用网络可视化软件Cytoscape进行蛋白质网络的可视化和枢纽基因筛选。 结果 本研究在烟雾病患者的大脑中动脉与颞浅动脉样本间鉴定出138个DEGs，包括18个上调基因和120个下调基因。GO富集分析显示，以上DEGs在细胞外基质、受体配体活性和生长因子活性等方面显著富集，可能与烟雾病相关的血管病变和神经保护机制有关。KEGG通路分析提示，DEGs主要在酪氨酸代谢通路中富集。通过PPI网络分析，共筛选出9个枢纽基因，包括骨膜蛋白（periostin，POSTN）、脑源性神经营养因子（brain derived neurotrophic factor，BDNF）、血小板衍生生长因子受体α（platelet derived growth factor receptor alpha，PDGFRA）、Thy-1细胞表面抗原（Thy-1 cell surface antigen，THY1）、ⅩⅤ型胶原蛋白α1链（collagen type ⅩⅤ alpha 1 chain，COL15A1）、成纤维细胞生长因子7（fibroblast growth factor 7，FGF7）、光蛋白聚糖（lumican，LUM）、层粘连蛋白α2亚基（laminin subunit alpha 2，LAMA2）和RELN（reelin）。此外，上调基因delta样典型Notch配体4（delta like canonical Notch ligand 4，DLL4）在本研究中首次被发现可能在烟雾病中扮演重要角色，或与烟雾病的病理性血管生成有关。 结论 细胞外基质、生长因子及其受体的表达失调等可能参与烟雾病的发病过程。DEGs分析筛选出的枢纽基因（POSTN、BDNF、PDGFRA、THY1、COL15A1、FGF7、LUM、LAMA2、RELN）以及DLL4可能在烟雾病的病理形成过程中发挥作用。 Abstract: Objective In this study, bioinformatics analysis of differentially expressed genes (DEGs) between blood vessel samples of patients with moyamoya disease were conducted to explore the potential pathogenesis of moyamoya disease. Methods The cerebral blood vessel samples from patients with moyamoya disease and internal carotid aneurysm were taken as research subjects. The linear models for microarray data (limma) package in R was used to analyze the GSE141025 dataset downloaded from the gene expression omnibus (GEO). The dataset included samples from 4 moyamoya disease patients and 4 internal carotid aneurysm patients, providing a total of 16 samples including one middle cerebral artery and one superficial temporal artery from each patient. A total of 12 samples of middle cerebral artery and superficial temporal artery from moyamoya disease patients and superficial temporal artery from internal carotid aneurysm patients were selected for DEGs screening. Gene ontology (GO) enrichment analysis and Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis on the DEGs were conducted using the clusterProfiler package in R. The STRING database was utilized to construct the protein-protein interaction (PPI) network, and the network visualization software Cytoscape was used to visualize the protein network and to filter hub genes. Results In the comparison between middle cerebral artery and superficial temporal artery samples from patients with moyamoya disease, 138 DEGs were identified, including 18 up-regulated genes and 120 down-regulated genes. GO enrichment analysis revealed that these DEGs were significantly enriched in extracellular matrix, receptor ligand activity, and growth factor activity, suggesting their potential involvement in vasculopathy and neuroprotective mechanisms associated with moyamoya disease. KEGG pathway analysis indicated that DEGs were primarily enriched in the tyrosine metabolic pathway. Through PPI network analysis, 9 hub genes were filtered, including periostin (POSTN), brain derived neurotrophic factor (BDNF), platelet derived growth factor receptor alpha (PDGFRA), Thy-1 cell surface antigen (THY1), collagen type ⅩⅤ alpha 1 chain (COL15A1), fibroblast growth factor 7 (FGF7), lumican (LUM), laminin subunit alpha 2 (LAMA2) and reelin (RELN). Additionally, the up-regulated gene delta like canonical Notch ligand 4 (DLL4) was firstly founded possibly associated with pathological angiogenesis of moyamoya disease in this study, suggesting that it may play a significant role in moyamoya disease. Conclusions The study indicates that the dysregulation of the expression of extracellular matrix components, growth factors and their receptors might be involved in the pathogenesis of moyamoya disease. The hub genes selected by DEGs analysis (POSTN, BDNF, PDGFRA, THY1, COL15A1, FGF7, LUM, LAMA2, RELN) and DLL4 may play a role in the pathological process of moyamoya disease.

The integration of underground coal gasification (UCG) and carbon emission reduction is expected to become an excellent green energy technology during the transitional stage from the current to the arrival of carbon neutrality, and even play an important role in the longer history of carbon neutrality in the future. Looking back at the research history and current situation, the systematic strategy for UCG emission reduction has been basically formed, which can be summarized into five specific approaches. Among them, the targeted underground in-situ regulation can reduce the CO2 release and promote the quality and yield increase of UCG synthesis gas, and the relevant strategies and approaches can be summarized as the Carbon Regulation and Reduction (CRR). There are many research achievements on the supercritical gas storage of UCG-CO2 in underground space, mainly focusing on storage media, storage space, storage capacity, etc., with some discussions for storage mechanisms. The mineralization and storage of UCG-CO2 in underground space are not constrained by the harsh conditions of geological stability and sealing, and there is a potential dual effect of both carbon sequestration and gas conversion, but there are not many research results yet. The previous exploration of UCG-CO2 reinjection, utilization and storage focuses on two aspects, such as enhancing coalbed methane production and improving the production of UCG synthesis gas, and a series of explorations have been initiated for the emission reduction and utilization of CO2 from the tail gas of UCG hydrogen production in recent years. The CRR, as an active emission reduction strategy, targetedly reduces the CO2 concentration in the UCG synthesis gas by adjusting the gasifying agent and its injection method, and there are many theoretical achievements and preliminary on-site verification, which are expected to become a practical clean coal technology that integrates clean energy production and carbon reduction. Reviewing the progress and analyzing the shortcomings, the scientific and technological research for UCG carbon emission reduction has made many substantial achievements, but also still faces some challenges of sustainable development, and the future study should focus on four aspects. One is to prioritize the development of UCG-CO2 underground conversion and utilization technology with a focus on the UCG-CRR based on feasibility. The second is to focus on the shortcomings and to strive for the breakthrough of the collaborative mechanism and key technological bottlenecks of both UCG emission reduction and synthesis gas quality improvement. The third is to make solid progess and promote the prior implementation of UCG-CRR pilot tests and engineering demonstrations for the achievement of practical results step by step. The fourth is to ensure the implementation and establishment of the “trinity” policy support system for the UCG emission reduction consisting of carbon neutrality and management strategy, special science and technology action plans, and professional talent training.

烛果油富含1，3-硬脂酸-2-油酸甘油三酯（StOSt），是可可脂的理想改良剂。为探究烛果油在巧克力中的应用效果，以市售烛果油为研究对象，分析其组成特征，并研究其与可可脂复配的相行为及复配体系在经典黑巧克力中的抗霜性能。结果显示：烛果油中的StOSt（57.1%）和甘油二酯（6.65%）含量显著高于可可脂的（23.8%、4.48%），且烛果油中低熔点甘油三酯含量也高于可可脂的；烛果油在室温下的固体脂肪含量比可可脂低10~20百分点；当烛果油与可可脂按质量比9∶ 1复配时，其相应的巧克力抗霜性显著强于可可脂基巧克力，其中，合适的StOSt、POSt、POP三者比例（10∶ 3∶ 1）提高了油基的相容性，而适当的甘油二酯含量有助于保持相的均一性。综上，烛果油可应用于巧克力中以延缓巧克力起抗霜。Kokum fat is rich in StOSt and is an ideal modifier for cocoa butter. In order to explore the effect of its application in chocolate, commercial kokum fat was taken as the research object, its composition characteristics were analyzed, and the phase behavior of the compound with cocoa butter and the bloom resistance abilities of the compound system in classic dark chocolate were studied. The results showed that the contents of StOSt (57.1%) and diglycerol (6.65%) in kokum fat were significantly higher than that in cocoa butter (23.8%, 4.48%), and the content of low-melting triglyceride in kokum fat was also higher than that in cocoa butter. The solid fat content of kokum fat at room temperature was 10 to 20 percentage point lower than that of cocoa butter. Chocolate formulated with the binary fat containing 90%of kokum fat and 10% of cocoa butter exhibited desirable bloom resistance compared with cocoa butter based-chocolate. It was suggested that when the ratio of StOSt/POSt/POP was 10∶ 3∶ 1, the compatibility of fat phase could be improved, and desirable levels of diglycerides contributed to maintain phase homogeneity. In conclusion, kokum fat can be applied in the production of chocolate to delay the bloom of chocolate.

ObjectiveTarget tracking is an important application of unmanned surface vehicles (USVs). This study proposes a relative time-varying tracking position (RTTP) strategy to improve the tracking stability and address the problem that the reference trajectory obtained by the relative fixed tracking position (RFTP) strategy contains inflection points and leads to tracking instability.MethodsA first-order hysteresis filter is used to process the target USV's heading variation. The time-varying tracking position is then designed according to the filtered data, the target tracking problem is transformed into a trajectory tracking problem and the reference trajectory is obtained. Finally, model predictive control (MPC) is used to achieve the tracking of the target USV.ResultsThe simulation experimental results show that the tracking effect of the USV under the RTTP strategy is more stable with the root mean square error (RMSE) of the tracking distance decreased by 28.06% and the energy consumption reduced by 5.93%. It also has advantages in the smoothness of the control volume.ConclusionsCompared with the traditional RFTP strategy, the proposed RTTP strategy can effectively improve the stability of USV target tracking, giving it practical significance for the target tracking of USVs.

Seven samples of Wuyi rock tea (cv. Shuixian) stored for different times (0, 5, 10, 15, 20, 25, and 30 years) were collected to investigate the effect of storage time on the flavor quality of Wuyi rock tea by the combined use of sensory evaluation, non-volatile and volatile composition analysis and chemometrics methods. The results showed that the transformation of the flavor quality of Wuyi rock tea during storage was divided into three stages: 0–5, 10–15, and 20–30 years. As the storage time increased, the taste gradually transformed from mellow to stale, and a sour taste appeared at the middle stage of storage and then faded away at the late stage. The aroma gradually changed from flowery and fruity to aged, woody and herbal. A significant decrease in the content of tea polyphenols, catechins-like and theaflavins and an increase in the content of soluble sugars were the major reasons for the taste changes. Changes in the contents of 15 characteristic volatiles, including indole, trans-nerolidol, dihydroactinidiolide, hotrienol, α-terpineol, methyl salicylate, β-ionone, and (Z)-hexanoic acid-3-hexenyl ester, were the key factors affecting the aroma changes. This study provides a scientific reference for the storage and consumption of Wuyi rock tea.

Word embedding, as the first step in natural language processing (NLP) tasks, aims to transform input natural language text into numerical vectors, known as word vectors or distributed representations, which artificial intelligence models can process. Word vectors, the foundation of NLP tasks, are a prerequisite for accomplishing various NLP downstream tasks. However, most existing review literature on word embedding methods focuses on the technical routes of different word embedding methods, neglecting comprehensive analysis of the tokenization methods and the complete evolutionary trends of word embedding. This paper takes the introduction of the word2vec model and the Transformer model as pivotal points. From the perspective of whether generated word vectors can dynamically change their implicit semantic information to adapt to the overall semantics of input sentences, this paper categorizes word embedding methods into static and dynamic approaches and extensively discusses this classification. Simultaneously, it compares and analyzes tokenization methods in word embedding, including whole and sub-word segmentation. This paper also provides a detailed enumeration of the evolution of language models used to train word vectors, progressing from probability language models to neural probability language models and the current deep contextual language models. Additionally, this paper summarizes and explores the training strategies employed in pre-training language models. Finally, this paper concludes with a summary of methods for evaluating word vector quality, an analysis of the current state of word embedding methods, and a prospective outlook on their development.

Backgroud Diabetic foot is a common complication of diabetes patients, most of whom are seriously ill with rapid disease progression. A well-performing risk prediction model for the development of diabetic foot can help healthcare professionals to identify high-risk patients and take early interventions. Objective To systematically review the risk prediction models for diabetic foot, and provide reference for the construction and optimization of the model. Methods PubMed, Cochrane Library, Embase, Web of Science, CNKI and Wanfang Data were searched to collect the related studies on risk prediction models for diabetic foot from inception to May 15th, 2022. Two reviewers independently screened the literature, extracted data and evaluated the quality of models using prediction model risk of bias assessment tool (PROBAST). Meta-analysis of the predictors in the model was performed using Stata 17.0 software. Results A total of 13 papers were included, containing 13 models, 12 of which had AUC>0.7. Model calibration was performed on 7 models and 8 models were validated. PROBAST results showed that 1 of the 13 included papers was at low risk of bias and the remaining 12 were at high risk of bias; for model applicability, only 1 was of low applicability. The results of Meta-analysis showed that age (OR=1.13, 95%CI=1.04-1.24), glycated hemoglobin (OR=1.56, 95%CI=1.26-1.94), foot ulcer history (OR=5.93, 95%CI=2.85-12.37), previous amputation (OR=7.79, 95%CI=2.74-22.17), diminished sensitivity of the monofilament test (OR=1.59, 95%CI=1.42-1.78), foot fungal infection (OR=6.14, 95%CI=1.71-22.01), and kidney disease (OR=2.09, 95%CI= 1.65-2.65) were independent influencing factors for diabetic foot (P

The submicron sized polysilsesquio-xane microspheres were synthesized by hydrolysis and polycondensation two-step method using methyltri-methoxysilane as reaction monomer in deionized water solution. The effects of conductivity of deionized water and pH value of monomer on hydrolysis time, polymerization time, and particle size of microsphere were investigated, as well as the effect of chloride ion content in monomer on surface cleanliness of microspheres. The morphology, particle size distribution, organic functional groups and thermal properties of the microspheres were analyzed and characterized by scanning electron microscopy, particle size distribution testing, Fourier transform infrared spectroscopy and thermogravimetric analysis. The results showed that under the conditions of deionized water conductivity less than 15 μS/cm, pH value of monomer 4-5 and chloride ion content in monomer less than 0.023 mg/L, it was favorable for preparation of submicron polysilsesquioxane microspheres with high level cleanliness .

The Bohai Bay Basin is one of the key areas for the exploration of buried hill oil and gas resources in China. In order to create a new prospect for the exploration of the Archaean buried hills in this area, the reservoir-forming laws and main controlling factors of the Archaean buried hill reservoir in the Liaodong Bay area were studied. Based on drilling data such as stratum, logging, and seismic data, this paper classified the lithology and distribution patterns of Archean buried hills in the Liaodong Bay area, and analyzed the dominant reservoir space types and controlling factors. The results show that the Archean buried hills in the Liaodong Bay area are composed of schist, metamorphic granite and cataclastic rocks, with schist being the predominant lithology. The current structure is high in the south and low in the north. The strata are relatively intact in the north, while the upper part of the strata in the south shows evidence of denudation. The proportion of igneous rocks increases gradually from north to south. The metamorphic rocks are dominated by fracture reservoirs. The content of mafic minerals is inversely correlated with the brittleness of rocks. Tectonic deformation led to fracture development. Three sets of structural fractures were developed in the Archean buried hills of the Bohai Bay Basin, i.e., NNE shear fractures and SN tensile fractures were developed in the stress directions of NE strong shear and SN strong compression in the early Yanshanian period, NE shear fractures and NE tensile fractures were developed in the stress directions of NW strong extension and NE weak shear in the early Himalayan period, and EW tensile fractures and NE and NW conjugate shear fractures were developed in the stress directions of NE strong shear and NW weak extension in the late Himalayan period. The degree of regional tectonic activity controlled the effectiveness of the fractures. The Yanshanian movement was the main stage of fracture formation in metamorphic rock reservoirs. During the Himalayan period, fractures were mainly filled and semi-filled with calcite, and effective fractures could be formed through dissolution in the later stage.

In order to meet the unmanned needs of thin coal seam fully mechanized mining faces and address the issue of requiring dedicated personnel to monitor the cables of existing coal mining machines, an automatic cable dragging system for coal mining machines has been designed, The system has a rated power of 15 kW, a maximum length of 400m for the working face, and is suitable for a maximum speed of 30 m/min, This article focuses on the overall design, parameter design, and adaptation design of the automatic cable dragging system for coal mining machines, It elaborates in detail on four key technologies: the design of the cable chain transmission system based on dynamic simulation analysis, the track floating alignment technology suitable for complex working faces, the self adaptive control technology based on speed and torque, and the fast cable disassembly and assembly technology. The system design, mechanical structure, control strategy, fault protection, and other difficulties have been solved, It solves the problems of system design, mechanical structure, control strategy, and fault protection, and achieves that the cable clamp is always in a slightly tensioned state, Engineering application was carried out in the 14301 working face of Zhangjiamao Coal Mine, achieving adaptive and normalized operation of the entire working face, with a follow-up rate of 94.7%, The system has a reasonable structure, high reliability, convenient disassembly and maintenance, and can be retrofitted on existing working faces, It has strong scalability and promotes the progress of unmanned mining technology in thin coal seams.

This is an essay in the field of mining engineering. In the current new energy development strategy under the new situation, lithium is an indispensable key raw material to support the development of the new energy vehicle industry and promote the new energy revolution. It is positioned as one of China's 24 national strategic mineral resources, and its strategic position is extremely important. The safety of lithium resources and the continuous supply of lithium mineral products are related to the healthy and stable development of many industries and the national economy in China. China is rich in lithium resources. However as the world's largest consumer of lithium resources and producer of lithium batteries, lithium is highly dependent on foreign countries, and there are hidden dangers in the supply system. It is urgent to improve the safety and security of China's lithium resources. Based on the combing and research on the distribution of lithium resources at home and abroad and the supply and demand situation of lithium mineral products, this paper analyzes and elaborates on the main problems and causes faced by China's lithium resources. This paper analyzes the main problems faced by China's lithium resources and their causes, and puts forward opinions and suggestions on the development and utilization, scientific and technological research, industrial structure, institutional mechanism, personnel construction, market regulation, overseas strategy and other aspects in order to increase production of lithium resources and maintain supply and stability, which provides useful reference for ensuring the safety and stability of China's lithium resources and the healthy and orderly development of lithium mining industry.

Marine stock enhancement is not only commonly reported to amplify the target species production but also induces some potential threats or effects at multiple ecological levels in the receiving ecosystem. Studies on the interaction between released and naturally occurring organisms are necessary to avoid or minimize the adverse impacts of invasive species from stock enhancement in the receiving system. Chinese shrimp Fenneropenaeus chinensis, are an important stock enhancement species, and in recent years approximately 10 billion have been released annually into the coastal waters of China. Owing to fishing pressure and the ecological complexity of the open sea, the interaction between the released shrimp and native species may be weak and undetectable. Studies on the ecological impacts of such intensive releasing activities are limited. Therefore, in this study, an in-situ mesocosm experiment was carried out to determine if the released shrimp altered the relative composition and niche characteristics of fish, the results of which could serve as a reference to the local risk management of the species stock enhancement. The mesocosm was located in the shrimp-releasing channel of Weihe, Laizhou Bay, from April to September 2019. A cross design of four treatments with three replicates was conducted in the mesocosm. The habitats were homogenized across the replicates by mixing substrates and filtering seawater with a 0.28 cm sieve. The number of individual shrimp larvae released into net enclosures in each of the four treatments were: A) 2 400, B) 1 800, C) 1 200, and O) 0. The treatments were designed to represent the release of 1 billion, 750 million, 500 million, and no shrimp larvae (none-releasing) in the coastal waters of Laizhou Bay, respectively. The released shrimp larvae had an average body length of (1.63±0.18) cm and an average body width of (0.38±0.12) cm. At the end of the experimental period in September, shrimp and fishes were recaptured and their Levin's niche breadth and overlap indices were examined in each enclosure. Results indicated that within the enclosures of the four treatments, the recapture rates of shrimp ranged from 8.16% to 12.69% and had an average value of 9.87%. The number of recaptured shrimp increased with the number released, and had the highest value in enclosure A. However, the total biomass, average individual mass, and recapture rate of shrimp did not show a similar pattern among enclosures. The recapture rate of shrimp was significantly different among the treatments and had the highest value in enclosure C. The fish species composition was similar across all four treatment enclosures and included six species with three different feeding habits: Omnivores (Konosirus punctatus and Liza haematocheila), zooplanktivores (Thryssa mystax and Sardinella zunasi), and fish/shrimp predators (carnivores) (Acanthogobius sp. and Sparus microcephalus czerskii). Of the fish species, Acanthogobius sp. dominated in all enclosures, while S. m. czerskii occurred in only a few. There was no significant difference in the number and biomass of total fishes and carnivorous fishes among enclosures. There were more omnivorous fishes in the released enclosures A–C, while the number of zooplanktivorous fishes decreased when shrimp were released and had the highest number and biomass in the non-released enclosure O. Moreover, fishes with different feeding habits had variable niche breadths among the four treatment enclosures. Most fish species had a wider niche breadth in enclosures with released shrimp (enclosure A–C) than in enclosure O. Both the fish´s niche overlap indices and the species pairs with high niche overlap (> 0.75) decreased in the order non-released enclosure O > released enclosure B > enclosure C > enclosure A. The carnivorous fish Acanthogobius sp. had more pairs with niche overlap indices (> 0.75) in the non-released enclosure O than in the other three treatments. A similarity analysis and multidimensional plot indicated that enclosures A and O could be differentiated by the relatively long similarity distance and little overlap area. The results of the experiment suggest that the shrimp recapture efficiency did not increase when shrimp were released. In the waters of the study area, released shrimp could have a positive effect on the total output of both shrimp and fish, especially for omnivorous and carnivorous fishes, as the shrimp could share predation pressure and provide food for them. In addition, the shrimp release may affect the relative composition and niche characteristics of fish by increasing their niche breadth and reducing the overlap between fishes with different feeding habits, and the impacts may be more detectable as the shrimp number increases.

旨在产出高质量棉籽蛋白并对脱酚液中的棉子糖进行回收利用，对棉籽蛋白脱酚工艺及棉子糖的制备工艺进行了研究。结果表明：控制棉仁粉末度在21.44%左右，脱酚溶剂甲醇体积分数80%~90%，料液比在1∶ 0.56~1∶ 0.63之间，不仅可以达到最佳的棉籽蛋白脱酚效果，还可稳定采出棉子糖含量在3%以上的脱酚液；控制一次浓缩挥发性组分在85%左右，絮凝时pH为8～9，脱色时pH为5～6，二次浓缩挥发性组分为45%左右，所提取的棉子糖粗品中棉子糖含量可达到85%，重结晶后棉子糖含量可达到98%以上。In order to produce high quality cottonseed protein and recycle the raffinose in the degossypol solution, the degossypol process of cottonseed protein and the preparation process of raffinose were studied. The results showed that under the conditions of cottonseed kernel powder degree about 21.44%, volume fraction of methanol(degossypol solvent) 80%-90%, and the ratio of material to solvent 1∶ 0.56-1∶ 0.63, it could not only achieve the best degossypol effect of cottonseed protein, but also could stably produce the degossypol solution with the raffinose content over 3%. When volatile constituent in the primary concentration was controlled to about 85%, the pH was 8-9 during flocculation, the pH was 5-6 during decolorization, and volatile constituent in the secondary concentration was about 45%, the raffinose content in the extracted crude product could reach 85%, and the content of raffinose after recrystallization could reach more than 98%.

Biodiversity loss is one of the major crises facing humanity today, and with none of the biodiversity targets represented by the Aichi Biodiversity Targets being met, there is an urgent need to promote transformative change to halt and reverse the trend of biodiversity loss. Nature-based solutions (NbS) have emerged as an important way to address the global crisis due to its inherent principles involving holistic and systemicness, diversity, stability, sustainability, trade-offs, and compatibility. The relationship between biodiversity and NbS is analyzed from a mechanistic and functional perspective, and the pathway of NbS as a proxy for biodiversity conservation is revealed by restoring of ecosystem complexity and trophic levels to put nature on the path. We here propose the dual intensions of promoting NbS for biodiversity conservation, as (1) the goal aimed at enhancing diversity, stability, and sustainability of ecosystem, and (2) the tool involves use natural processes. Based on the above understanding of the link between NbS and biodiversity, this paper further compares the conceptual connotation of NbS with the consistency of biodiversity conservation, as well as the NbS methods for biodiversity conservation including natural, agricultural and urban area. Practical cases of NbS for biodiversity conservation or synergy of NbS for biodiversity are summarized in align with differentiated typical ecosystems. The multiple benefits of NbS for biodiversity conservation, climate change and sustainable development are discussed. The vision of integrating NbS into strategic planning for biodiversity conservation is presented to provide a reference for promoting the implementation of Kunming-Montreal Global Biodiversity Framework and the mainstreaming of NbS in biodiversity conservation.

Haloxyfop-R-methyl (HPME) is a selective herbicide for gramineous plants and has a removal effect on the coastal invasive organism Spartina alterniflora. In order to assess the risks of HPME on marine organisms in the governance process of Spartina alterniflora, this paper used the static-test method to evaluate the acute toxicity of HPME on four marine organisms. The results showed that four test organisms all showed muscle relaxation, decreased exercise capacity, and slow response under HPME exposure. As the test time prolonged, the mortality rate gradually increased, indicating that HPME had neurotoxicity and cumulative toxic effect on marine organisms. The 96 h median lethal concentration (LC50) of HPME for Mactra veneriformis、Apostichopus japonicus larvae、Cynoglossus semilaevis fry and Assiminea. lutea were were 0.888 mg/L, 1.382 mg/L、0.656 mg/L and 8.674 mg/L, respectively. The safe concentrations (SC) were 0.088 8 mg/L, 0.138 2 mg/L, 0.065 6 mg/L and 0.867 4 mg/L. According to the environmental safety assessment test guidelines for chemical pesticides, HPME was highly toxic to Cynoglossus semilaevis fry and Mactra veneriformis, and was moderately toxic to Apostichopus japonicus larvae and Assiminea. lutea. The results provided a reference for HPME in the elimination of Spartina alterniflora.

Liquid metal-cooled fast reactors (LMFRs) are being investigated in many countries as the next-generation nuclear reactors. Fuel rods in LMFRs are commonly arranged in a triangular pitch and assembled in a hexagonal fuel wrapper. The fuel pin will be subjected to various forces during the irradiation process, leading to the phenomena of bending and deformation. As a result, the performance of the fuel assembly is directly related to reactor safety, reliability, and economy. To investigate the effect of rod bending on the flow and heat transfer characteristics, a computational fluid dynamics (CFD) model of the Karlsruhe Institute of Technology (KIT) 19 rods fuel assembly has been built. The model contains 19 duel rods using lead-bismuth eutectic as working fluid. The mesh of the assembly with and without wire, correlation method of turbulence model and fluid-solid coupling heat transfer were considered in the CFD model. The established model was validated, and the simulation results were found to be in good agreement with experimental data. The simulation results indicated that the SST k-ω turbulent model and Cheng-Tak turbulent Prandtl correlation can be combined to precisely obtain the flow and heat transfer behavior of the coolant in sub-channels. The results show that in the case of neglecting the wire spacer, the rod bending narrows the coolant channel and forms a local high-temperature region. In the deviating direction of bending, the coolant channel widens, promoting mixing and causing coolant temperature to decrease. The maximum circumferential temperature difference of the center rod bending, edge rod bending, and corner rod bending is 46 K, 17 K and 16 K, respectively. In the case of considering the wire spacer, the geometry of the bending rod has been simplified. The influence of the bending wire on the coolant flow resistance is reduced, which results in the failure to reflect the deterioration of coolant heat transfer due to bending. Therefore, the high-temperature region generated by rod bending is less significant due to the wire mixing effect, the high-temperature area is mainly concentrated in the narrow area where the rod contacts the wire. This study reveals the effect of fuel rod performance on the safety and reliability of lead-bismuth reactors, which provides a reference for the reactor safety design. Further study is necessary to reveal the complex heat transfer characteristics and flow mechanism in the case of rod bending with wire spacer. The work presented in this paper represents an important step toward the research on fuel rod bending scenarios in the LMFR fuel assembly.

Due to the complex environment and ground stress at depth, and the various cross-sectional shapes and sizes, the damage types of deep roadways are diversified. The maximum ground stress, maximum compressive strength, and the corresponding support methods are compared by systematically analyzing the influence of high stress and dynamic pressure on the deep weak surrounding rock of roadways. And the stress intensity ratio is proposed to evaluate the support difficulty of surrounding rock of roadways. Then, the concept of active-passive full space collaborative control is proposed, and the core of the concept is to control the deformation of the roadway through active support methods such as destressing, grouting and bolt-cable to bring the self-supporting capacity of the surrounding rock of roadway into play, forming an active support body, and restoring its partial bearing capacity. Using passive support methods such as concrete-filled steel tube sets and U-shaped steel sets with high support resistance to form a passive support ring to assist or mobilize the bearing capacity of the rock surrounding roadways. Additionally, the mechanical mechanism of the collaborative support for concrete-filled steel tube sets and bolt-cable were analyzed, and the active-passive full space collaborative control technology and construction technique were developed and applied in the field. The study shows that the bolt-cable can reduce the bending moment and shear force of the concrete-filled steel tube sets, while reducing the axial force of the support and protecting the steel tube and the core concrete with poor tensile properties. The active-passive full space cooperative control technology has been successfully applied in deep roadway subjected to dynamic pressure and weak rock roadway in Jincheng Hudi Coal Mine and Yangquan Xinyuan Coal Mine, which has further developed the theory and technology of equal-strength support in deep roadway.

A method was established to determine 22 free amino acids in food for special medical purposes by ultra-performance liquid chromatography. After extraction with sulfosalicylic acid and derivation with 2,4-dinitrofluorobenzene (DNFB), the samples were eluted with acetonitrile water-ammonium formate as mobile phase. Amino acids were separated by HSS T3 column and detected with diode-array detector by external standard method. Results showed that, the 22 amino acids were linear in the range of 2~100 µg/mL with correlation coefficients higher than 0.99. The limits of detection (S/N≥3) were 10 mg/100 g, and the limits of quantification (S/N≥10) were 25 mg/100 g. The recoveries were in the range of 90.1% and 109.1% with relative standard deviation (RSD) from 0.8% to 6.9%. This method was simple, efficient, accurate and reproducible. It was suitable for determination of 22 free amino acids in food for special medical purposes, which could provide technical support to ensure the quality and safety.

Objective To explore the influencing factors of herpes zoster neuralgia in order to provide reference for the diagnosis and the treatment of this disease. Methods We retrospectively analyzed 89 cases of craniofacial herpes zoster and 168 cases of non-craniofacial herpes zoster hospitalized in the First Affiliated Hospital of Wannan Medical College from January, 2019 to December, 2019. The demographic and clinical characteristics were compared between these two groups. Pearson analysis was used to determine the correlation between NLR and pain score and severity score of the skin lesions. Logistic regression was used to analyze the risk factors for herpes zoster neuralgia. Results There were no significant differences in age, gender, pain score and severity of skin lesions between the two groups when admitted to hospital. Patients with craniofacial herpes zoster had a higher rate of pustules, blood blister and necrosis than that with non-craniofacial herpes zoster (25.84% vs. 15.48%, χ2=4.05, P=0.044). Moreover, the NLR were higher in patients with craniofacial herpes zoster than that with non-craniofacial herpes zoster (4.11±1.62 vs. 2.35±1.51, t=6.27, P

Eight samples of No.11 coal in Sangshuping Mine were used for organic geochemical study, Gas chromatography-mass spectrometry (GC-MS) and X-ray fluorescence spectrometry (XRF) were combined with the test results of proximate analysis, sulfur forms and random vitrinite reflectance, the organic matter sources and coal-forming environment of No.11 coal from the Sangshuping mine, Shaanxi Province were comprehensively analyzed. The results indicate that the total sulfur content of the coal sample is 3.29%, and the mean vitrinite oil-leaching reflectance is 2.01%, which is high-sulfur lean coal. The phase parameters of major elements indicate that the coal samples are mainly formed in reductive sedimentary environment. There are two types of carbon number distribution of n-alkanes in saturated hydrocarbon: the front peak type main carbon peak is C16, and the back peak type is main carbon C26; Combined with the distribution characteristics of ∑C22−/∑C23+、(C21+C22)/(C28+C29)、Pr/nC17、Ph/nC18 indicated that the parent material of organic matter come from aquatic organisms and higher plants. The OEP value was between 0.49 to 1.05,with an average value of 0.84, indicating that No.11 coal of Sangshuping has undergone different degrees of biodegradation. In the analysis of saturated hydrocarbon steroidal terpanes, the ratio of w(Ts)/w(Tm) is between 0.83-1.21 and w(Ts)/[w(Ts)+w(Tm)] is between 0.45-0.55, indicating that the thermal evolution degree of coal sample is high. In the analysis of aromatic compounds, the methyl rearrangement of trimethylnaphthalene and the distribution characteristics of methyl phenanthrene index are correlated with the high thermal evolution degree of coal samples. The aromatic hydrocarbons were dominated by naphthalene, phenanthrene and biphenyl series, and the sulfur-containing compounds in the trifluorene series (oxygen-fluorene, sulfur-fluorene, fluorene) are obviously higher than the oxygen-containing compounds, which also indicates the coal-forming environment under higher salinity partial reduction conditions.

Based on the previous study on the long-term rise of water level in Bengbu monitoring center well, we analyze 59 short-time rises of the water level in Bengbu monitoring center well from 2017 to 2020. By selecting rainfall parameters in different periods andestablishing multiple regression equations, the results show that there is a certain relationship between 59 short-term rise of water level and some rainfall parameters. According to the analysis results of earthquake cases above ML2.0 and 13 non rainfall events around Bengbu, the surrounding area of Bengbu is mainly affected by ML2.0—3.0 earthquakes, with slightly weaker crustal stress release and minimal impact on underground fluids in Bengbu. Earthquakes above ML3.0 mainly occurred in the west of Anhui Province and near the Tanlu fault zone, with strong seismic activity. The observation data of underground fluid in Bengbu changed greatly and lasted longer. It is concluded that the short-time rise of water level is related to the change of crustal stress in Bengbu area while excluding the influence of rainfall. It can be seen that Bengbu monitoring center well has a certain prediction efficiency, which can reflect the changes of seismic stress field around Bengbu, and is of great significance for the analysis and prediction of earthquake precursor observation data.

Underground coal gasification (UCG) is the inevitable choice for China’s energy development and driven by the strategy of the development of efficient coal energy structure. The industrialization process needs to be promoted by all parties in coordination, and the making of industrial policy is the first to bear the brunt. Based on the background and extensive investigation on relevant situations at home and abroad, the difficulties faced by the making of industrial policies for UCG are analyzed and demonstrated, and the countermeasures and suggestions to solve the difficulties are put forward from four aspects, including the strategic value of UCG industrialization, market access and legal status of UCG projects in relevant countries, method of filing and approval of UCG projects in China, and the thinking on the making of UCG industrial policies. It is shown that the UCG project involves coal, oil and natural gas in the management of mineral resources. From the perspective of environmental protection management, it involves groundwater, soil and surface ecology, atmosphere and many other aspects. The management responsibility belongs to multiple government departments, and the application and approval process is very complex. Although relevant countries have made many attempts in the making of UCG industrial policies, there is no current and sustainable policy for improving UCG industry, which has become a “short board” for the promotion of UCG industrialization. Foreign experts have suggested to their own governments to launch the UCG technology as soon as possible through the policy and regulatory framework, and to eliminate social concerns about the environmental safety of UCG. For a long time, China has adopted the “one case, one discussion” method for the filing and approval of UCG projects. It is difficult for some UCG projects to be approved, which has greatly restricted the industrialization process of UCG. Based on the above difficulties, it is suggested that the government should formulate and issue an operable UCG industrial policy system, focusing on five directions: establishing a UCG project market access and approval system, clarifying the use of mineral resources and fiscal and tax preferential policies for UCG projects, bringing UCG scientific and technological innovation into the national major science and technology plan, building a UCG scientific and technological innovation platform system, and creating a high-quality professional talent training base of UCG. The purpose is to provide legal guarantee for promoting the industrialization of UCG in China.

The landslides induced by typhoons and rainstorms in Southern China are often shallow, fluidized and clustered. A large number of investigations have shown that vegetation infiltration has a significant impact on the formation of granite residual soil landslides. However, most of the current studies have focused on the effect of vegetation roots on soil infiltration. The influence mechanism of vegetation infiltration enhancement effect on shallow landslides has not been revealed. Therefore, the mass landslide disaster on September 9, 2019 in Longchuan County in Guangdong is taken as an example, and a large number of landslide site investigations are made to identify the geological environment conditions and vegetation development in the landslide area and analyze the infiltration effect of vegetation on shallow landslides. The “double-ring method” is used to measure infiltration rate of different vegetation types, and to analyze the infiltration process and infiltration law of different vegetation types. A typical landslide profile is selected to establish a geological model, and the Geo-Studio software is used to simulate the seepage law of shallow landslide and the stress-strain characteristics of the soil under heavy rainfall conditions (250 mm/d). Finally, combined with the simulation results and field investigations, the infiltration effects of vegetation and their response mechanisms to shallow landslides under heavy rainfall are analyzed. The results show that vegetation can effectively enhance the permeability of soil, and the order of permeability is coniferous forest land, shrub forest land and bare land. Under the influence of vegetation infiltration effect, rainwater infiltration to the bottom of the root-soil composite layer will cause water stagnation, the shallow soil tends to be saturated rapidly, the pore water pressure and seepage force in the soil increase instantaneously, the soil is saturated with water, the residual soil softens, and the weight of the slope increases, which eventually leads to the overall instability of the slope. The research results explain the formation mechanism of granite residual soil landslide in high vegetation covered area under heavy rainfall in Southern China, and provide scientific basis for early warning and prediction of such disasters, which are of great significance.

[Objective] The factors influencing landslide potential of loess terraces and the associated landslide formation mechanisms were studied in order to provide a scientific basis for the prevention and control of loess terrace landslides. [Methods] With data from the Google Earth Engine cloud computing platform for Pengyang County, Ningxia Hui Autonomous Region, we used the random forest algorithm to extract terrace distribution information in the study area. Based on the overlay analysis method, the high and extremely high susceptibility zones of potential loess terrace landslides in the study area were determined. Eight influencing factors were selected, and the certainty factor method was used for analysis. [Results] ① The terrace area in the study area accounted for 47.28% of the total area of the county. There were 86 potentially unstable slopes, and there were no deforming areas within the influence range of terraces. ② The high and extremely high susceptibility zones for potential landslides of loess terraces accounted for 46.68% of the total area of high and extremely high susceptibility zones in the study area (27.64% of the total area of terraces in the study area). ③ Rainfall, stratum lithology, gully density, and slope direction had strong controlling effects on the spatial distribution of potential landslides of loess terraces in the study area. [Conclusion] The main controlling factors for potential landslides of loess terraces in the study area were rainfall and stratum lithology, especially in the area where the annual rainfall was more than 450 mm and there were Quaternary stone loess with paleosol strata.

In recent years, fishery species have decreased in size and quality in the Yellow River estuary seas due to the effects of climate change and human activities, such as water and sediment regulation of the Yellow River, overfishing, and sewage discharge, among others. At the same time, the fishery resource structure has changed greatly: Small-sized fish with low value, shrimps and crabs became the main catches. To conserve natural resources and maintain local fishery harvests, conservation efforts such as stock enhancement and fishing quotas have been employed. Research on the biological characteristics of important fish can provide a scientific basis for the rational utilization and stock enhancement of fishery resources in the future, and it can also offer support for making relevant fishery policies.Liza haematocheila is an economically important fishery species in the Yellow River estuary and mainly feeds on zooplankton, phytoplankton, and organic detritus, which limits eutrophication and promotes energy and carbon cycling at the ecosystem level. The species plays an important role in ecosystem function and the maintenance of biodiversity. This study investigated the biological characteristics of L. haematocheila to provide a scientific basis for its conservation and rational utilization in the Yellow River estuary. Furthermore, it can provide basic biological data for the study of ecological restoration in the Yellow River estuary.This study evaluated the distribution of body length and weight, the relationship between body length and weight, reproduction, growth, death, and development. All of the analyses were based on sampling data from set nets between April and November 2020.The body length range of L. haematocheila was 45~460 mm, the average body length was 149 mm, and the modal body length range was 55~185 mm. The body weight range was 2~1100 g, the average body weight was 83 g, and the modal body weight range was 2~80 g. Both the average body length and body weight were the highest in May and the lowest in September. Overall, small individuals were the most common, and individuals with a body length of less than 200 mm accounted for more than 78%. Analysis of variance showed significant monthly differences in both average body length and weight of L. haematocheila. The relationship between body length and body weight showed a strong correlation within and between months [W=3.17×10‒5L2.82, (R2=0.980 5, n=984)]. The growth of L. haematocheila was negatively allometric, with the growth of body length being faster than that of body weight.The body condition of L. haematocheila decreased with time, though it increased in July and fluctuated with a downward trend from July to November. The nadir body condition was observed in June (1.102±0.173) and the peak body condition was observed in July (1.535±0.467).The rate of gonadal development varied from month to month, and the proportion of individuals who did not reach gonadal maturity was large, with an undeveloped gonad proportion of more than 50% per month. There was a peak spawning period from April to May.The growth curve of L. haematocheila was fitted, and its growth parameters were estimated using the ELEFAN method. The total death coefficient of the population was estimated using a length-converted catch curve, the natural death coefficient was estimated using the empirical formula of Pauly, and the population development rate was calculated. The results indicated that the asymptotic length (L∞) of L. haematocheila was 608 mm, the growth rate (K) was 0.31 a−1, total death coefficient (Z) was 1.42 a−1, natural death coefficient (M) was 0.51 a−1, fishing death coefficient (F) was 0.91 a−1, and its population development rate (E) was 0.64. The L. haematocheila resource was overfished in the shallow coastal waters of the Yellow River estuary, and its open fishing length (L50) was only 57.4 mm in this production survey.Fixed-net harvesting led to overfishing in the Yellow River estuary from April to November 2020, with juvenile fish and supplementary stocks experiencing the greatest impact. We should reconsider the management strategies for L. haematocheila in the Yellow River estuary, and promote stock enhancement at the same time. Artificial propagation technology for L. haematocheila should be considered for supplementing L. haematocheila in the Yellow River estuary seas. Research on the release time, release of krill size, population characteristics, growth, and development should be addressed to provide an informed and scientific basis for stock enhancement.

The Yellow River estuary is one of the three largest estuaries along the coastal waters of China, along with the Yangtze and Pearl River estuaries. Its adjacent seawaters are rich in biological resources, with abundant fish habitat, spawning grounds, and migration channels in the Bohai Sea and the Yellow Sea. However, as the waters are too shallow for a survey ship, data was insufficient for research in the intertidal zone of the salt and freshwater interchange. Instead, by interviewing and analyzing the daily catches by the set net of the local fishermen, this study explored the fishery biodiversity in the intertidal zone of the Yellow River estuary from April to November 2020. Yellow River estuary is rich in fishery resources, especially small fishery organisms and fish recruitment stocks. There were monthly variations in the dominant species composition and biodiversity index. A total of 61 species were recorded, most of which were fish and crustaceans. The diversity, evenness, and species richness index increased in summer (July and August) and decreased in autumn (October and November). By cluster analysis of the species compositions, the surveyed months can be divided into two groups: May to September, and October to November. Lateolabrax maculatus and Liza haematocheila were the most common and dominant species in all surveyed months. The main contributors to the catch of each month were: snails from April to July, snails and fish in August, fish in September, and crabs from October to November. Catches by the set net were mainly composed of individuals with body mass < 2 g from April to September. From body mass-frequency distributions, fish with body mass < 10 g were the main contributors to total catches from April to September. The mean body mass of fish in all surveyed months was 13 g/ind.. The dominant fish species with body mass with < 20 g were: Gobioidei in April; L. maculatus in May; Konosirus punctatus in June; Pennahia argentata, Gobioidei, and L. haematocheila in June to August; and Sardinella zunasi, Thrissa kammalensis, T. mystax, Sillago sihama, Tylosurus melanotus, Gobioidei, and L. haematocheila in September. From the above results, the local set net fishery survey proved to be an effective method of collecting fishery data in the intertidal zone and can be incorporated in studies considering the distribution of fishery resources and breeding grounds in the seawaters adjacent to estuaries. In addition, this study provided clear evidence that set net fishing practices could severely impact the natural recruitment and stock enhancement of fish resources due to the low selectivity of nets and the overlap with larval fish migration channels. The number of larval fish captured by the set net fishery was, roughly estimated, several times higher than the local enhancement released. To minimize the effects of net mesh size, considering the spatial-temporal distributions of fish larvae, set net fishing practices should be concentrated to summer and early autumn, though further research is required to comprehensively account for both the protection of fishery resources and livelihoods.

Two kinds of composite mineral admixtures were prepared by grinding iron tailings powder and silicon powder in the ratios of 3∶2 and 4∶1, respectively to substitute cement for the preparation of mortar and concrete samples. The basic properties of iron tailings-silica fume composite mineral admixture mortar and concrete have been studied through microstructure analysis, strength and durability analysis. Results show that: as the content of the composite mineral admixture increases, the heat of hydration reaction, compressive strength, split tensile strength and freeze-thaw durability of the sample gradually decrease; and adding iron tailings powder can increase the pore structure of the hardened mortar test block, which reduces the compressive strength and freeze-thaw durability of the concrete. However, increasing the amount of silica fume can increase the strength of the hydration reaction of the sample, and increasing the silica fume can reduce the content of Ca(OH)2. The CSH gel produced by the hydration reaction of silica fume can also refine the pore structure, thereby improve the microscopic properties, compressive strength, split tensile strength and freeze-thaw durability of concrete; make up for the negative impact of iron tailings powder on concrete performance. On the whole, the compressive strength of modified concrete is more than 85% of that of ordinary concrete, which can meet engineering requirements.

The geomorphology of southern Ningxia is dominated by loess hills, with gullies and well-developed small landslides in the area, making surface deformation monitoring difficult. To explore the identification method of geological hazards in the loess hilly area, Jingyuan district in the city of Guyuan in Ningxia Huizu Zizhiqu is taken as the study area, and the SBAS-InSAR technology is applied to process a total of 11 periods of ascending L-band ALOS-2 data collected from July 2016 to May 2021 to obtain the deformation rate of the Jingyuan district. Combined with high-resolution optical images, a comprehensive analysis is carried out according to factors such as deformation rate, deformation scale, slope, and disaster-bearing body. A total of 27 suspected hidden dangers are identified. After field verification, 22 of them show obvious signs of deformation and have clear hazard-bearing bodies. The time-series deformation analysis of the typical hidden danger points shows that these areas have continuous and significant surface deformation during the monitoring period, and the maximum subsidence rate reaches 91.53 mm/a. The results show that the combined L-band SAR and high-definition optical image data and the application of the integrated remote sensing identification method are highly accurate and are of high applicability in the area. The next step is to collect L-band data on a combination of ascending and descending orbits and to conduct in-depth research on the basis of LiDAR data from drones in order to further improve the accuracy of geological hazard identification and to provide technical support for the precise prevention and control of geological hazards.

In order to improve the mechanical properties of the metal matrix composite, the copper-graphene composites were prepared by FSP (friction stir processing) method. The samples were analyzed through the metal microstructure observation test and mechanical test, the effects of agitation speed and the amount of graphite on the microstructure and tensile strength of the composites were investigated, and the strengthening mechanism of the composites was studied. The results show that the effect of graphene on copper matrix is mainly reflected in load transfer and hindering dislocation movement and grain boundary growth in copper matrix. With the introduction of graphene, the grain in the nugget area has been significantly refined. The reason for grain refinement is the mechanical stirring of the stirring head and the obstruction of graphene to grain growth during recrystallization. The tensile strength of the copper-graphene composites is 5% higher than that of the base metal, up to 27749 MPa. The copper-graphene composites with good properties and uniform distribution of graphene can be prepared by FSP method, which can effectively improve the mechanical properties of copper alloy and provide theoretical basis and technical reference for its wide application.

Multi-sensor multi-target tracking is a popular topic in the field of information fusion. It improves the accuracy and stability of target tracking by fusing multiple local sensor information. By the fusion system, the multi-sensor multi-target tracking is grouped into distributed fusion, centralized fusion, and hybrid fusion. Distributed fusion is widely applied in the military and civilian fields with the advantages of strong reliability, high stability, and low requirements on network communication bandwidth. Key techniques of distributed multi-sensor multi-target tracking include multi-target tracking, sensor registration, track-to-track association, and data fusion. This paper reviews the theoretical basis and applicable conditions of these key techniques, highlights the incomplete measurement spatial registration algorithm and track association algorithm, and provides the simulation results. Finally, the weaknesses of the key techniques of distributed multi-sensor multi-target tracking are summarized, and the future development trends of these key techniques are surveyed.

The occurrence of time delayed rockburst usually has strong randomness and will pose a great threat to construction safety. Excavation disturbance and blasting disturbance will have impact of varying degrees on the potential time delayed rockburst area. It is of great significance to carry out studies of the characteristics and mechanism of time delayed rockburst in a TBM tunnel under the blasting disturbance. Based on a TBM headrace tunnel, five time delayed rockburst occurred in K54+000—K54+700 section during demolition tunnel blasting excavation are studied by using theoretical analysis and comparative analysis method. The results show that (1) strong and medium rockburst areas are located near gentle dip faults. Short and small concealed joints and fine joints with filling are developed in surrounding rocks. The slight rockburst is far from the fault or near the normal fault. Except for the fine joints with filling, at least one steep structural plane with filling tendency and dipping in SW direction is developed. (2) The time delayed rockburst of the TBM tunnel has longer delay blasting time and longer lag working face distance, and the disturbance effect of blasting on the TBM tunnel is relatively small. (3) Blasting disturbance makes it easy for the surrounding rock instability in the potential time delayed rockburst area, which accelerates the process of time delayed rockburst. The research results can provide a useful reference for the early warning and prevention of time delayed rockburst in TBM tunnels.

Bamboo and wood products for food contact are widely used in our family and working life, such as disposable chopsticks and chopping boards. Due to the special texture of bamboo and wood, some fungicides could be used to ensure their effects of application and to extend the storage period. There is a growing concern of whether residual fungicides in treated bamboo and wood products will migrate into foods to be harmful to human body. Furthermore, the methods of detecting residual fungicides are also focused as research hotspots. Based on the domestic and foreign research progress of fungicides in bamboo and wood products, this paper reviews the classification, application, limit standards and detection methods of fungicides in bamboo and wood products, and summarizes the migration rules of fungicide in systems of food simulation, which provid references for the analysis of fungicides. Finally, the problems of existing detection and migration study about fungicides in bamboo and wood products for food contact are summarized, and the research prospects are discussed.

Objective: To analyze the main etiology and clinical features of cirrhosis in Shangri-La area of Yunnan and provide clinical data for prevention and control in such area. Methods: A total of 104 patients with cirrhosis admitted to the People’s Hospital of Diqing Tibetan Autonomous Prefecture from January 2019 to June 2021 were enrolled, and the etiological composition and main clinical characteristics of patients with cirrhosis in Shangri-La were analyzed retrospectively. Results: Patients with cirrhosis ranged from 33 to 86 years old, with an average age of (59.5±11.3) years old. The male to female ratio was 9 to 4. It revealed that 62.5% patients were Tibetans, 17.31% were Han Nationality, 15.38% were Yi Nationality. For Child-Pugh grading, 38 cases (37%) were with Child-PughA, 56 cases(54%) were with Child-pugh grade B, and 10 cases (9%) cases were with Child-pugh grade C. The main reason for the visit was abdominal distension. For etiological composition, alcoholic cirrhosis accounted for 38%. Hepatitis B cirrhosis accounted for 48%. Hepatitis C cirrhosis accounted for 1%. Mixed sclerosis accounted for 13%. The age of onset of cirrhosis caused by all causes is younger than those in other parts of the country, especially the age of onset of alcoholic cirrhosis is younger and the prognosis remission rate after standard treatment was only 1%. Conclusions: Viral hepatitis is still the main cause of cirrhosis in this region, followed by alcoholic liver disease and mixed cirrhosis. Attention should be paid to the harm of alcohol to human body education in this region, and strengthen the prevention and treatment of viral hepatitis.

The Yellow River Basin has active geological structure, rapid geomorphic evolution and significant regional differentiation of climate, resulting in many types of major disasters in the basin, wide distribution and strong paroxysm. Taking the Loess Hilly Region in the south of Ningxia as the research area, this paper introduces the concept of loess potential landslide of terrace. By combining historical data collection, remote sensing image interpretation, field investigation and mathematical statistics, it analyzes the development characteristics and distribution rules of loess potential landslide of terrace, and analyzes its formation reasons. The results show that: （1）There are 26 loess potential landslide of terrace in the study area, which are mainly distributed in the Quaternary loess, with a larger number of medium and long slopes, mainly loess potential landslide of terrace of shallow and middle-level, and the scale is mainly small. （2）The loess potential landslide of terrace are mainly distributed in loess hilly areas and large undulating mountain areas, the elevation interval of 1 800~2 000 m, and the slope direction is southeast, South and southwest in space; It is mainly distributed in rainy season or seismicity period in time. （3）Topography, stratum lithologic, rainfall, surface water and human engineering activities are the main factors for the loess potential landslide of terrace. The research results have guiding and reference significance for the risk identification and risk management of loess potential landslide of terrace in the Loess Hilly Region in Southern Ningxia and the Yellow River Basin.

In order to address the problem that the dynamic decay of shear strength of expansive soil in the process of rainfall infiltration cannot be considered in the traditional slope stability analysis of expansive soil, indoor direct shear test was carried out to systematically study the influence of dry density and water content on the indicators of shear strength of expansive soil, viz., cohesion and internal friction angle. At the same time, the stability analysis of the expansive soil slope based on the strength reduction method was carried out with the shear strength testing results, and the change law of slope stability with the dynamic decay of shear strength was obtained. The results show that the increase of water content and the decrease of dry density will cause the decay of cohesion and internal friction angle of expansive soil, and the decay of cohesion is significant, while the decay of internal friction angle is less; the stability of expansive soil slope is mainly controlled by the water content of weathering layer, and with the increase of water content of expansive soil, the slope gradually evolves from stable state to unstable state, while the influence of dry density on the stability of expansive soil slope is relatively small.

The Weibei Oil Field of the Ordos Basin has reservoirs of ultra-low permeability with small pores and complex pore throat structures. Imbibition is obvious at the early stage of water injection, which improved the effect of oilfield development. However, the characteristics of imbibition and the extent of EOR by imbibition are not clear. By collecting core samples from the third member of the Triassic Yanchang Formation in the Weibei Oil Field, physical property test, cast thin section observation, scanning electron microscope test, high pressure mercury injection and various imbibition experiments were carried out to study the reservoir physical properties and pore throat structure characteristics of the study samples, and to make imbibition experiments under different media types and different oil saturation. Three types of pores were discovered in the study area, namely, dissolution pore, intergranular pore and intergranular pore. The pore throat structure corresponding to different pore types are largely different. Pore throat structures of the reservoirs dominated by dissolution pores and intergranular pores gradually deteriorates. The oil displacement efficiency of fractured reservoir is higher than that of matrix reservoir with the values of 34.8% and 23.2%, respectively. The imbibition experiment under residual oil saturation shows that imbibition can improve the displacement efficiency of reservoir, but the increase is limited (5.3%-6.7%). The main factors affecting oil displacement efficiency are physical property, pore throat structure, medium type and oil saturation. When the reservoir physical property is higher, the pore throat structure is better and the oil saturation is relatively lower, the reservoir imbibition is relatively weak and the imbibition displacement efficiency is relatively low.

Extreme heavy precipitation in the Yellow River basin mainly occurred between June and August in summer. It is of great significance for improving climate prediction and preventing and reducing disaster events to study the characteristics of synoptic conditions of extreme heavy precipitation in summer in this basin. Using the daily precipitation data in summer at the 247 ground-based meteorological stations in the Yellow River basin from 1961 to 2017, we first analyze the distribution characteristics of regional extreme heavy precipitation events in this basin. Second,according to the dominant circulation systems at 500 hPa,the typical circulation patterns affecting regional extreme heavy precipitation in summer in this basin are classified into the blocking type,the low-trough type,and the typhoon-peripheral type. The characteristics of extreme heavy precipitation,water vapor transport and evolution,and circulation under the blocking type and low-trough type of synoptic conditions before the events are analyzed. The results show that (1) the thresholds of extreme heavy precipitation in summer in the Yellow River basin gradually increase from the east to the west and from the north to the south during past 57 years. The frequency of extreme heavy precipitation in the upstream area is higher than that in other areas. (2) The distribution characteristics of zonal wind anomalies at 200 hPa are similar for the blocking-type and low-trough type synoptic conditions,whose anomalies show a "- + -" pattern in the range of 20°-55°N from the north to the south. Their circulation patterns at 500 hPa vary greatly,with the low-trough type dominated by the zonal circulation and the blocking type dominated by the meridional circulation in the mid- and high- latitudes of Eurasia. The former has many small troughs and ridges in the range of 30°-65°N,while the latter is controlled by positive geopotential height anomalies in the low latitudes. (3) The water vapor of blocking-type synoptic condition mainly comes from the Indian Ocean and the Pacific Ocean,while that of the low-trough type mainly comes from the Pacific Ocean and the South China Sea. (4) The blocking high that causes extreme heavy precipitation mainly develops locally,and the signal of its development can be captured 1-2 weeks before its occurrence. The trough that causes extreme heavy precipitation mainly moves,and its initial signal and strong signal appear about 7 d and 2-3 d before the occurrence of extreme heavy precipitation,respectively.

The research progress of isotopic fractionation in the process of shale gas/coalbed methane migration has been reviewed from three aspects: characteristics and influencing factors, mechanism and quantitative characterization model, and geological application. It is found that the isotopic fractionation during the complete production of shale gas/coalbed methane shows a four-stage characteristic of “stable-lighter-heavier-lighter again”, which is related to the complex gas migration modes in the pores of shale/coal. The gas migration mechanisms in shale/coal include seepage, diffusion, and adsorption/desorption. Among them, seepage driven by pressure difference does not induce isotopic fractionation, while diffusion and adsorption/desorption lead to significant isotope fractionation. The existing characterization models of isotopic fractionation include diffusion fractionation model, diffusion-adsorption/desorption coupled model, and multi-scale and multi-mechanism coupled model. Results of model calculations show that the isotopic fractionation during natural gas migration is mainly controlled by pore structure, adsorption capacity, and initial/boundary conditions of the reservoir rock. So far, the isotope fractionation model has been successfully used to evaluate critical parameters, such as gas-in-place content and ratio of adsorbed/free gas in shale/coal etc. Furthermore, it has shown promising application potential in production status identification and decline trend prediction of gas well. Future research should focus on: (1) the co-evolution of carbon and hydrogen isotopes of different components during natural gas migration, (2) the characterization of isotopic fractionation during the whole process of gas generation-expulsion-migration-accumulation-dispersion, and (3) quantitative characterization of isotopic fractionation during natural gas migration in complex pore-fracture systems and its application.

The preparation technology and microstructure properties like crystal structure, hardness, adhesion and wear resistance of the existing TiNbN hard films were analyzed and overviewed in this paper. Besides, the mechanical properties such as hardness, wear resistance and thermal shock resistance of TiAlNbN hard films were summarized. Finally, the development of TiAlNbN hard film was prospected.

Objective To study the effect of matrine on paraquat(PQ)-induced pulmonary fibrosis in mice and its possible mechanism. Methods Mice were divided into the control group, the paraquat(PQ) group and the matrine group randomly. The pulmonary fibrosis model was induced by intraperitoneal injection of paraquat (18 mg/kg). Twenty-four hours after modeling, the treatment group was intragastrically administered with matrine (100 mg/kg). Twenty-eight days later, the lung tissues of each group were collected; HE staining and Masson staining were used to observe the severity of inflammation and fibrosis in the lung tissue; Ashcroft scale was used to evaluate pulmonary fibrosis, and the content of hydroxyproline(HYP) in lung tissue of mice was detected by alkaline water method; Western blot was used to detect the expression of collagen Ⅰ and collagen Ⅲ; The expression of epithelial-mesenchymal transition(EMT)-related proteins[ alpha-smooth muscle action(α-SMA), E-cardherin and vimentin] was detected by immunofluorescence staining. Results The pulmonary structure of paraquat group mice was damaged significantly with deposition of collagen fiber. Compared with the control group, Aschcroft scale of the model group significantly increased(P＜0.001)and paraquat upregulated the expression of EMT-related proteins significantly. After matrine intervention, the pathological evidence of pulmonary fibrosis was decreased and the content of hydroxyproline, collagen Ⅰ and collagen Ⅲ in lung tissue was decreased(P＜0.001). The protein expression of α-SMA and vimentin was inhibited(P＜0.05,P＜0.001). Conclusions Matrine has a protective effect on paraquat-induced pulmonary fibrosis in mice, which may be mediated by inhibition of EMT-related proteins.