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The occurrence of coal mine accidents is mostly caused by the instability and failure of the coal pillar and its overlying roof rock layer. To study the influence of different coal-rock height ratios on the deformation failure and energy evolution mechanism of the coal pillar-roof system, uniaxial loading and cyclic loading and unloading tests are conducted on coal-rock structural body with coal-rock height ratios of 1∶3, 1∶2, 1∶1, 2∶1, and 3∶1, respectively. The relationship between deformation and energy evolution of coal-rock structural body are analyzed, and the stability of coal-rock structural body are quantitatively evaluated through the load-unload response ratio. The test results show that the peak strength of coal-rock structural body under uniaxial loading and cyclic loading gradually decreases with the increase of coal-rock height ratio. The peak strength of coal-rock structural body under cyclic loading test is lower than that in uniaxial loading test. The higher the coal-rock height ratio, the smaller the reduction rate of the peak strength of the structural body under cyclic loading; the input energy, elastic energy and dissipative energy of the composite increase nonlinearly with the increase of stress. The coal-rock height ratio is positively proportional to the average elastic strain, average elastic energy, average residual strain, average dissipative energy, total residual strain and loading and unloading response, and inversely proportional to the total elastic strain, total elastic energy and total dissipative energy of the composite during cyclic loading.

Chinese coal reservoirs are characterized by “Three High and One Low”, and the pore structure of coal is an important factor affecting the permeability, the degree of drainage difficulty and the subsequent drainage mode. In order to accurately characterize the full scale pore size structure of coal, three methods of high pressure mercury injection, low temperature liquid nitrogen and carbon dioxide adsorption are used. Based on the compressibility correction of the high pressure mercury injection experimental data, combined with the fractal theory, the dominant pore size characterization sections of different experimental methods are analyzed, and the full scale joint characterization of 10 groups of coal samples in Yunnan Laochang mining area is realized. The results show that: The compression coefficient of coal matrix ranges from 7.06179×10−11 to 1.23531×10−10 m2/N, and the cumulative mercury intake after correction is reduced by 15.89% ～ 27.82% compared with that before correction, with an average of 21.65%. The coal matrix begins to be compressed when the mercury injection pressure reaches 0.7 MPa. Irreversible damage occurs when the mercury injection pressure reaches 14.3 MPa. In the liquid nitrogen adsorption experiment, the pore volume increases gradually with the increase of the pore size on the whole, the pore area tends to be stable and the adsorption volume is small, and the pore adsorption rate is the fastest. The overall rate decreases with the increase of the pore size. The adsorption volume curve and differential curve of carbon dioxide adsorption experiment stage are basically consistent, and the pore volume decreases with the increase of pore size. The mercury injection fractal curve can be divided into three sections. When lgPi > 1.1, the fractal dimension reaches the maximum, and the coal matrix suffers irreversible compression failure. The low temperature liquid nitrogen adsorption fractal curve takes Pj/Ps =0.5 as the boundary line. The fractal dimension of 2−5 nm pore size is between 1.93−2.92, with an average value of 2.57. The fractal dimension of 5−100 nm pore diameter is 2.16−2.76, with an average value of 2.49, indicating strong heterogeneity. Based on the three experimental results, with 1.5nm and 100nm as the splicing points, the coal samples are dominated by micropores with pore sizes ranging from 0.41nm to 0.86nm, with the largest proportion of pore volume.

Graphene quantum dots (GQDs) have attracted great research interest due to their remarkable quantum confinement and edge effects. In addition to exhibiting stable photoluminescence, it also has many advantages such as low cytotoxicity, good solubility and chemical inertness, making it widely used in bioimaging, photocatalysts and sensors. The industrial development of GQDs has been seriously hampered by the expensive raw materials and tedious operation of traditional preparation methods. Coal and its derivatives not only possess the characteristics of low price and abundant reserves, but also show greater advantages than graphite, graphene, graphite oxide and other carbon materials in the preparation of GQDs due to its inherent internal disorder structure and small crystal domain. GQDs can be prepared by simply stripping the aromatic ring clusters inside the coal and its derivatives through physical, chemical or electrochemical methods. This review first summarizes the “top-down” synthesis method of coal-based graphene quantum dots (C-GQDs) and its pros and cons. Then the structural morphology, chemical composition, fluorescence properties of C-GQDs and their influencing factors are analyzed. Further, we describe the progress in applications of C-GQDs in fields such as sensors, bioimaging and energy Finally, the future development of C-GQDs is discussed from the perspectives of preparation methods, carbon source selection and research directions, and the following experimental schemes are proposed: (1) Experiment with H2O2 as oxidizer and thermally altered coals as carbon sources； (2) Experiments other than oxidation with sulfuric acid and nitric acid using superhigh organic sulfur coals as carbon sources； (3) Experiment on coal macerals as a carbon sources. In addition, the combination of experimentally derived basic data and computer simulation technology can solve the problems of current research such as single fluorescence color and low quantum yield. The goals of clean utilization of coal resources and green development of GQDs have been achieved.

Pyrolysis is the basis of clean coal technologies such as coal liquefaction and gasification, especially for the low-rank coal. To further investigate the pyrolysis characteristics of low-rank coals, a series of different vitrinite/inertinite ratio ZJZ, MTH, and DT coals (V/I: 0.1, 0.76, and 1.76 respectively) are used as the research objects. The chemical structure of the sample was analyzed with Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction technology (XRD). The pyrolysis process and gas release behavior of coal samples at 30−900 °C was checked by TG-MS. The results show that the chemical structure content of low-rank coals with different V/I is quite different. Compared with the inertinite-rich ZJZ coals, the vitrinite-rich coals have relatively rich aliphatic structures, long aliphatic chains, and oxygen functional groups. Especially for DT coal, it has more C—O content. The corresponding aromatic structure content decreases with the increase of the mirror-inert ratio. With the increase of V/I in the coal, the aromatic layer spacing d002, the ratio of the aromatic layer size to the aromatic layer stacking height (La/Lc) increase, and Lc, La and the number of stacking layers (N) decrease. The weight loss ratio of DT, MTH, and ZJZ coal during pyrolysis is 36.4%, 32.2%, and 28.9% respectively. As the V/I decreases, the final pyrolysis gaseous product yield and the maximum pyrolysis rate decrease accordingly. During the pyrolysis process, the small molecular gas, such as H2, H2O, CH4, CO, CO2, are released; In addition, the content of released gas is closely related to the maceral composition. The mass of small molecules produced by inertinite-rich coal is almost lower than that produced by vitrinite-rich coal. Because the vitrinite in coal contains more aliphatic structures, and the polycondensation capacity between the aromatic layers is stronger, the free radicals fragment are easily formed during the thermal process and then combined into gas.

Objective To investigate the effect of the SMAC gene on paclitaxel sensitivity and cellular activity in lung adenocarcinoma cells based on the caspase-3/Bcl-2/Bax signaling pathway. Methods A paclitaxel-resistant cell line A549/Taxol was established for lung adenocarcinoma, and the cells were divided into four following groups: pcDNA-NC (transfected with pcDNA-NC blank vector), pcDNA-SMAC (transfected with pcDNA-SMAC vector), siRNA-NC (transfected with siRNA-NC empty virus vector), and siRNA-SMAC groups (transfected with siRNA-SMAC lentiviral vector). The SMAC mRNA expression in cells was detected by qRT-PCR; cell sensitivity was detected by MTT; cell proliferation ability was detected by cloning assay; cell invasion ability was detected by Transwell; apoptosis ability was detected by flow cytometry assay; and caspase-3, Bcl-2 and Bax protein expression in cells were detected by Western blot analysis. Results The SMAC mRNA expression was significantly lower in A549 cells compared with BEAS-2B cells (P < 0.05). The SMAC mRNA expression was significantly higher in the pcDNA-SMAC group than that in the pcDNA-NC group cells (P < 0.05). The SMAC mRNA expression was significantly lower in the cells of the siRNA-SMAC group (P < 0.05) than that in the siRNA-NC group. The SMAC mRNA expression was significantly lower in the cells of the siRNA-SMAC group (P < 0.05) than in the siRNA-NC group. Compared with the pcDNA-NC group, the cell IC50, cell clone number, cell invasion ability, and Bcl-2 protein and Bcl-2/Bax ratio were significantly lower in the pcDNA-SMAC group, the cell resistance index reversal was 2.51-fold, and the apoptosis ability and caspase-3, as well as Bax protein expression, were significantly higher (P < 0.05). Compared with the siRNA-NC group, cell IC50, cell clone number, cell invasion ability, and Bcl-2 protein and Bcl-2/Bax ratio were significantly higher in the siRNA-SMAC group, and apoptosis ability and caspase-3 and Bax protein expression were significantly lower (P < 0.05). Conclusion High expression of SMAC increases paclitaxel sensitivity, inhibits cell growth and invasion, promotes apoptosis in lung adenocarcinoma cells, and has a regulatory effect on the caspase-3/Bcl-2/Bax signaling pathway.

To address the issue of weight gain and abnormal lipid metabolism caused by clozapine and olanzapine administration in patients with schizophrenia， a qualitative and systematic review was carried out， thus providing references for clinical treatment and future research. This review embraces the aspects of pharmacotherapy， traditional Chinese medicine treatment and so on.

During solution mining and the mining of well and rock salt, the settling rate of insoluble particles in rock salt cavity is an important technical parameter in the design of brine extraction process. To study the settling rate of insoluble particles, the free settling experiment on single particle with large particle size(1.0 mm < d < 6.5 mm, d is the particle size) and the settling experiment on particle group with small particle size(d < 0.6 mm) were conducted by means of static settling method. The results indicate that particle size is the main factor affecting the settling of single insoluble particle, while the settling rate of rock salt insoluble particle group is negatively correlated with the mass fraction of insoluble particles in solution, positively correlated with particle size and negatively correlated with the mass concentration of NaCl solution. The research results are of great significance to rock salt solution mining for underground salt cavern storage and rock salt solution mining.

Synthetic Aperture Radar (SAR) is widely used in ship surveillance. High-Resolution Wide-Swath (HRWS) SAR data are simultaneously collected, which introduces challenges and offers new research opportunities. SAR-based ship-surveillance technologies and the performance requirements of SAR systems are reviewed and summarized. Furthermore, the characteristics of HRWS SAR imaging and ship surveillance technologies are considered in tandem, and preliminary research results on ship detection, feature extraction, and classification are discussed. Finally, we point out issues to be addressed in future work.

In order to improve the added value utilization of gasification fly ash and make it suitable as a filler for polymers, the gasification fly ash was ground and modified. The modified gasification fly ash (CGFA) was used as a functional filler, epoxy resin (EP) was used as the matrix, and carboxyl-terminated liquid nitrile rubber (CTBN) was added to prepare EP/CTBN/CGFA composites. The effects of different content of CGFA on mechanical properties, microstructure and thermal stability of EP/CTBN/CGFA composites were investigated. The results show that with the increase of CGFA content, the thermal stability of EP/CTBN/CGFA composites is improved, and the tensile strength and impact strength first increase and then decrease. When the addition amount of CGFA is 5%, the tensile strength of EP/ CTBNCGFA composite reaches the maximum, which is 10% higher than that of composite without CGFA. As a filler, the gasification fly ash can improve the mechanical properties and thermal stability of EP materials, and reduce the industrial production cost. [ABSTRACT FROM AUTHOR]

The conventional terahertz radar suffers from limited operation range for long-distance, noncooperative target detection due to the low transmitter power and atmospheric attenuation effect, both of which pose a hindrance in meeting the requirements of warning detection applications. To improve the radar detection capability, this paper studies an ultrasensitive target detection method based on single-photon detectors to replace traditional radar receivers. The method is expected to considerably expand the operation range of terahertz radars. First, the statistical law of the number of echo photons of a terahertz single-photon radar system is analyzed, and the echo characteristics of the target are expounded from a microscopic perspective. Furthermore, a terahertz single-photon target detection model, incorporating the characteristics of a quantum capacitor detector, is established. In addition, the mathematical expression of the target detection performance is derived, and the performance is evaluated via simulations. Further, a target detection performance curve is obtained. Finally, a time-resolved terahertz photon-counting mechanism experiment is performed, wherein we realize high-precision ranging by counting echo pulses. This work can provide support for the research and development of ultrasensitive target detection technologies and single-photon radar systems in the terahertz band.

To investigate the germination physiological mechanism of Paris polyphylla seeds, different stages of the germination process were divided based on the seed embryo morphology and the changing rules in endogenous hormone content and related enzyme activities were analyzed at different stages. The results were as follows: (1) The germination process of the seeds could be divided into eight stages based on seed embryo morphology: non-germinating embryo stage (S1), heart-shaped embryo stage (S2), embryo swelling stage (S3), radicle not breaking through seed coat stage (S4), cotyledon petiole elongation and radicle breaking through seed coat stages (S5), lower hypocotyl breaking through seed coat stage (S6), upper hypocotyl elongation stage (S7), and radicle elongation stage (S8). (2) The α-amylase activity in the seeds was significantly higher than β-amylase activity at all germination stages. (3) Superoxide dismutase (SOD) activity was the highest at stage S5 and the lowest at stage S1; peroxidase (POD) and catalase (CAT) activities generally increased with seed germination progress; soluble protein content initially decreased and then increased with seed germination progress. (4) The contents of hormones such as indoleacetic acid (IAA), gibberellin (GA3), abscisic acid (ABA), and salicylic acid (SA) decreased overall, while 1-aminocyclopropane-1-carboxylic acid (ACC), jasmonic acid (JA), brassinolides (BRs) increased overall during seed germination. Cytokinins (CTKs) content showed no significant change. The ratios of IAA/ABA and GA3/ABA decreased initially and then increased, while CTKs/ABA continuously increased with seed germination progress. (5) The contents of ABA, IAA, GA3 were negatively correlated with embryo rate, while ACC, JA, BRs, POD, CAT, and β-amylase activity were positively correlated with embryo rate. In conclusion, the germination process of the seeds can be subdivided into eight stages based on seed embryo morphology, with varying endogenous hormone content and related enzyme activities at different stages. The activities of α-amylase and POD may be related to radicle elongation, while GA3 may affect the embryo formation, and ABA may inhibit the growth and development of the embryo.

In order to explore the influence of thermal effect and strain on gas drainage, a fluid solid thermal coupling model considering coal deformation, gas adsorption and thermal effect was established to simulate the influence of thermal effect and strain on gas drainage. The results show that the gas production rate is 11.48% higher and the gas production rate is 11.45% higher when the thermal effect is considered than when the thermal effect is not considered. The stronger the thermal effect, the greater the permeability, and the higher the gas production. This shows that the influence of thermal effect on gas drainage cannot be ignored; the influence of different strains on gas extraction is different, adsorption strain > temperature strain > pressure strain.

The technology of CO2-enhanced coalbed methane (CO2-ECBM) can reduce greenhouse gas emissions, and has the function of clean energy production and environmental protection. In order to study the drainage and production laws of CH4 production by CO2 injection in water-bearing coal seams under gas-water two-phase flow conditions, as well as the effects of different initial water saturation and CO2 injection conditions on CH4 production, CO2 storage, and reservoir permeability. A coupled fluid-solid-thermal model for competitive adsorption, temperature changes, coal deformation, and water transport was constructed. The high accuracy of the model was demonstrated by comparing with the field data, existing experiments and numerical solutions of existing model, and the advantages of the model were specified. CO2-ECBM numerical simulation were subsequently carried out using COMSOL. The results shown that, CO2 injection can enhance the rate and amount of CH4 production, which indicated the feasibility of CO2 injection to increase production. With the continuous CO2 injection, the CH4 concentration in the reservoir decreased, the CO2 concentration increased, the temperature near the gas injection well increased, the temperature near the production well decreased and the temperature from the gas injection well to the production well slowly decreased. Water phase relative permeability gradually decreased and gas phase relative permeability gradually increased during gas injection and extraction period. Due to the combined effect of effective stress and matrix shrinkage/expansion, the reservoir permeability exhibited a trend of “decrease-increase-decrease”. The higher the initial water saturation of the coal seam, the lower the CH4 production and the lower the permeability decrease. The maximum decrease in cumulative CH4 production was 15.19%. Ignoring the impact of water in coal seams can overestimate CH4 production, and the impact of coal seam water should be considered in numerical simulation. The higher the CO2 injection temperature and pressure, the greater the CH4 production and the greater the permeability decrease. The cumulative CH4 production increased by 13.27% and 39.77%, and permeability decreased by 20.4% and 46.14%, respectively. Increasing the CO2 injection temperature and pressure was conducive to increase CH4 production.

This article presents a case study of a patient who had Cronkhite-Canada syndrome in combination with an asymptomatic novel coronavirus infection. The patient exhibited clinical symptoms of loss of appetite, hair and nail loss, and skin pigmentation. Digestive endoscopy revealed widespread and varying-sized polypoid changes in the mucosa of the stomach, duodenum, and colon. During the course of the illness, the patient tested positive for novel coronavirus nucleic acid. Treatment with moderate doses of prednisone resulted in the patient's hair regrowth and decreased skin hypopigmentation. The article provides a summary of the patient's diagnosis and treatment and a review of relevant literature, with the aim of enhancing clinicians' understanding of the disease.

The combination of water-jet and disc-cutter rock breaking is a key technology to improve the rock breaking efficiency of the full-face shaft boring machine and achieve the mechanized development of deep resources. It is a crux problem of selecting reasonable parameters for pre-cutting kerfs. In this paper, firstly, it examined the working characteristics of rock breaking with a disc-cutter driven by a conical cutter-head. Then, based on the cohesive element method, a discrete-continuous coupled numerical model for rock breaking with a disc-cutter under pre-cutting kerfs conditions was established. Comparing the intact rock mass, the influence of different pre-cut kerfs distances and depths on the stress and rock fragmentation characteristics of the rock breaking was analyzed. The three stage characteristics of dense core formation, blocky rock slag formation, and Hertz crack propagation during rock cutting with a disc-cutter were elaborated. The asymmetric fragmentation characteristics of the rock mass and the formation mechanism of rock slag in different regions were presented. Finally, a comprehensive analysis was conducted from four aspects: the force acting on the disc cutter, the rock breaking area, the specific energy consumption for rock breaking, and the degree of rock slag crushing, and the optimal range of distance and depth values for pre-cutting kerfs was determined. The research results indicate that the pre-cutting kerfs can significantly reduce the penetration force and lateral force during the rock breaking process of the SBM cutters. Compared with intact rock masses, the peak penetration force decreased by 44.0%−10.3%. The peak lateral force decreased by 35.2%−6.5%. When the spacing and depth of pre-cut kerfs are small, it will limit the range of rock breaking by the disc-cutter, and at the same time make the fragmentation of the rock mass smaller, resulting in an increase in specific energy consumption for rock breaking. As the pre-cut depth increases, the rock breaking volume first increases and then tends to be stabilized, while the specific energy consumption first decreases and then remains unchanged. Finally, it was determined that the cutting distance was 70−90 mm, and the best rock breaking effect was achieved when the cutting distance was 60−80 mm. The rock breaking volume was doubled compared to the case without cutting, and the specific energy consumption for rock breaking decreased by 69.2%. This provides a reference for the parameter design and determination of the cutter head.

Zhejiang， as a crucial coastal province in China， deems the delineation of risk zones in its power system imperative for minimizing losses caused by typhoon disasters. Initially， the paper leverages historical data to comprehensively analyze meteorological features of typhoons in the Zhejiang coastal areas， focusing on aspects such as landing point distribution， path characteristics， temporal patterns， wind speed attributes， and precipitation features. Subsequently， an analysis of typhoon disaster characteristics in the Zhejiang power system is conducted. This entails examining the distribution of fault points in the transmission system， the relationship between the substation system and typhoon landing points， and the distribution of power outage percentages in the distribution system. Finally， utilizing historical data from both Zhejiang’s typhoon meteorology and power system， the paper creates a map outlining the risk zones for typhoon disasters. This includes a detailed delineation of high-risk areas for tower collapses， areas prone to wind deviations， and regions with high geological disaster risks. The analysis results aim to support risk assessment and response measures for typhoon disasters across various levels of the power grid.

Humanistic care is issuing a nurse's love and affection to a human being, and this type of care is formed based on nurse’s patience, compassionate love, responsibility, professional theory knowledge and standard nursing practice. There is an overlap between people with anxiety and people who have high blood pressure, and they can contribute to and exacerbate the other. This paper summarized the research status of humanistic care nursing interventions for patients with hypertension complicated with anxiety, and provided reference for decision making of clinical nursing practice of hypertension and improvement of prognosis. (人文关怀护理是以人文本, 护理人员以高度的耐心、爱心、责任心及专业理论知识和规范的操作为患者提供优质的护理服务。高血压和焦虑之间存在一定的关联, 可以互相影响并加重病情。本研究总结高血压合并焦虑患者的人文关怀护理研究现状, 旨在为临床护理方案的制定以及改善患者预后提供参考。)

In order to fully understand the current situation of water resources utilization in the cities in the Taihu Basin under the background of the most stringent water resources management system, this paper summarizes the existing problems, and explores the future development direction of sustainable water resources. Based on the perspective of water footprint, it studies the utilization of water resources in the Taihu Basin and eight cities including Shanghai in the basin from 2015 to 2019, combined with the LMDI (Lograrithmic Mean Divisia Index Method) model to analyze the driving effect of population, wealth, and technical level on the changing in water footprint, and build an evaluation index system for the sustainable use of water resources.The results show that the total water footprint of the Taihu Basin has been declining in the past five years, the industrial and agricultural water footprints have been declining, and the domestic water footprint has been rising. Among the cities, Shanghai has the largest total water footprint and Jiaxing has the smallest. Technical level factors have the greatest impact on water footprint change, and population factors have the least impact. The degree of affluence and population are positively driven, and the technical level is negatively driven. The water footprint structure of the Taihu Basin is relatively stable, Shanghai and Suzhou are highly dependent on external water resources. The overall water footprint benefit continues to increase, with significant differences among cities in each indicator the ecological security situation of the water footprint is not optimistic, but it has shown a continuous improvement in the past three years. The research results indicate that in the future, cities in the Taihu Basin should increase investment in water-saving technologies, techniques and equipment when formulating and adjusting water resources management policies, promote the efficient development and utilization of agricultural and industrial water, strengthen the management of domestic water quotas, and pay attention to the pressure of population growth on water resources, continuously improve the utilization rate of water resources, and realize the sustainable use of regional water resources. [ABSTRACT FROM AUTHOR]

ObjectiveTo analyze the research trends and cutting-edge hot spots in the field of multimorbidity in older adults from 2000 to 2023 to provide reference for related research.MethodsWe conducted a search in the Web of Science Core Collection database, specifically looking for articles or reviews in English on multimorbidity in older adults published between January 1, 2000 and October 24, 2023. VOSviewer 1.6.18 software was used to extract the contents in the literature and draw the cooperative network diagram of high-producing countries(≥30 articles) and institutions(≥43 articles) as well as the timeline diagram of high-frequency keywords(≥74 occurrences) co-occurrence relationship. CiteSpace 6.1.R6 software was used to co-occur and cluster analyze the information of authors, research institutions and countries. The "bibliometrix" package in R was used to analyze the evolution of keywords in the literature.ResultsA total of 2590 documents consisting of 2230 Articles and 360 Reviews were obtained. The worldwide publication count significantly increased since 2000. Among the countries, the United States had the highest number of publications (35.02%, 907/2590) and total citations(31 343 times) in this field. The University of Toronto in Canada had the largest number of articles(2.59%, 67/2590). Jenny Ploeg of McMaster University was recognized as the most prolific author(1.24%, 32/2590). When it came to journals, BMC Geriatrics had the highest amount of literature related to multimorbidity(3.82%, 99/2590). The key areas of research in this field included multimorbidity, older adults, frailty, aging, and polypharmacy. Notably, there was growing interest in studying the relationship between multimorbidity and aging in older adults, as well as the impact of frailty and polypharmacy on multimorbidities.ConclusionsIn recent years, research on multimorbidities in the elderly has primarily centered around examining the correlation between comorbidities and aging, as well as exploring the impact of frailty and polypharmacy on individuals with multimorbidities. Future research could delve into primary health care, comprehensive geriatric assessment for older adults with multimorbidities, and maintenance of their overall quality of life.

With the advancement of the dual-carbon goal， the integration of a large amount of new energy sources has posed new challenges to power balance of the system. In this context， research on methods for system reserve provision considering both economy and reliability has garnered significant attention. In this regard， a multi-timescale market clearing model considering the reserve demand curve has been constructed， so that the reserve clearing results take account of both economy and reliability. Besides， diverse reserve resources across multiple time scales are considered， allowing for the balance between supply and demand of the reserve under multiple time scales through coordinated interactions among these resources. Finally， it is verified by a case study that the proposed model realizes a rational allocation of reserve， thereby improving the operational economy， safety and reliability of the system.

To explore the antimicrobial activity of epidermis mucus, the basic components and amino acid composition were analyzed and the antimicrobial substances in the mucus were extracted in this study. Their antimicrobial activity, preservation effects on salmon were explored. The components with antimicrobial activity were isolated and purified by solid phase extraction, gel filtration chromatography and reverse phase high performance liquid chromatography. And the peptide sequences were identified. Then, the antimicrobial peptides were synthesized accordingly and their antimicrobial activities were verified. The results exhibited that the main composition of epidermis mucus of sturgeon was protein with 47.44%±0.59%. The total amino acid content was 459.68 mg/g, with a high content of basic amino acids and hydrophobic amino acids. The crude antimicrobial peptide exhibited significant antimicrobial activity against Bacillus subtilis. Crude antimicrobial peptide (50 mg/mL) significantly inhibited the growth of microorganisms and protein degradation during salmon preservation. The highest active component after final liquid chromatography purification exhibited an inhibition rate of 92.40%±4.50% against Bacillus subtilis and 75.43%±5.02% against Escherichia coli. The sequences of novel peptides were identified as HSETLHDV and PLTDWQL. The synthetic antimicrobial peptides of sturgeon epidermis mucus had obvious inhibitory effects on Bacillus subtilis, Escherichia coli and Shewanella baltica. Therefore, this study would provide a theoretical basis for exploring the antimicrobial value of sturgeon mucus and lay a foundation for the development and application of natural preservatives.

ObjectiveAs tip vortex cavitation (TVC) causes noise radiation and vibration, it is necessary to understand how to predict and control its development, and understand its mechanism in order to suppress it, especially in the field of ship propellers and other rotating machinery. MethodFocusing on an elliptical hydrofoil with an NACA 0012 cross-section, this study uses the Improved Delayed Detached Eddy Simulation (IDDES) turbulence modeling method and Schnerr-Sauer cavitation model to simulate TVC on the hydrofoil and analyze its behavioral characteristics under wet flow and cavitation flow conditions. After that, two active water injection methods, side injection and top injection, are introduced into the simulation to reduce and suppress cavitation inception respectively. ResultsTaking the cavity volume of the tip vortex as the criterion for cavitation suppression, compared with the condition without water injection, top injection can inhibit cavitation by 8.09%. Moreover, under the condition of side injection, the effect of the injecting flow on the cavitation is more obvious, reaching 10.47%. The results show that both top and side injection can effectively suppress TVC. ConclusionTop injection can change the flow direction and speed of the tip vortex incident flow, and increase the dissipation term of the turbulent kinetic energy; while in side injection, the energy it carries acts directly on the vortex structure of the hydrofoil, destroying the vortex and greatly suppressing the generation of cavitation.

In this paper, we report an elderly patient who had been experiencing poor appetite for one month and yellowing of the skin and sclera for two months before visiting the Department of Geriatrics at Peking Union Medical College Hospital. The patient's blood tests revealed significantly elevated levels of serum total bilirubin, direct bilirubin, and blood sugar. The serum IgG4 level nearly tripled. Abdominal imaging examinations revealed diffuse pancreatic lesions, narrowing of the intrapancreatic segment of the common bile duct, and thickening and marked enhancement of the common hepatic duct, left and right hepatic ducts, and branches. Blood glucose was also significantly elevated during the course of the disease. Moreover, nutritional assessment found that the patient was malnourished. After multidisciplinary discussion, a medium dose of oral methylprednisolone was prescribed to the patient due to his advanced age and multiple chronic conditions. The dose was then quickly reduced while the patient simultaneously received low-dose mycophenolate mofetil (MMF) treatment. As a result, the patient's bilirubin level significantly decreased, jaundice subsided, and his body weight returned to normal with improved physical function. Throughout the diagnosis and treatment process, a multidisciplinary team actively participated in discussions and gradually identified the underlying cause. This exemplifies the crucial role of interdisciplinary collaboration in effectively diagnosing and treating complex illnesses in elderly patients.

The construction of CO2 geological storage GIS (Geographic Information System) basic data platform is an important basis for deploying the CCUS (Carbon Capture, Utilization and Storage) full-chain demonstration project. By studying typical carbon storage data platforms at home and abroad, the characteristics of carbon storage data are analyzed: multi-source, multi-scale, and multi-type. There are several areas that need to be further investigated: the platform function is basically a data storage management display, and a further enhancement of model embedding and dynamic analysis is needed. Research on the synergy between CO2 storage and energy resources needs to be further strengthened. On this basis, the basic data management and processing platform architecture of CO2 geological storage GIS is preliminarily designed based on the data of Map GIS spatial database and SQL Server attribute database, and the system is constructed by using the Microsoft. Net Frame development framework and the Web GIS technology. The core logical structure of the system is divided into four layers, namely, resource data layer, technical support layer, business application layer, and user permission layer. There are three peripheral support systems including the security system, management support system and standard specification system. The key technologies of data platform construction include the multi-heterogeneous data fusion of carbon sequestration geological GIS data and three models, i.e., secondary development and import of sequestration capacity evaluation model, source and sink matching dynamic model, and energy and resource collaboration model. Four interfaces are preliminarily designed including the data platform home page interface, thematic maps and results output interface, basin-level results map interface, storage potential - source and sink matching - energy and resources collaborative data analysis interface. The construction of the CO2 geological storage GIS basic data management and processing platform will provide a scientific basis for the selection of carbon reduction and decarburization solutions at the source, the selection of geological storage sites for CCUS regional large-scale deployment and the implementation of CCUS large-scale demonstration projects.

Objective: This study aimed to prepare a nutritious instant noodle with regional characteristics. Methods: The process was optimized using whole potato flour, oat flour, and wheat gluten flour as the basic ingredients. The sensory score, breakage rate, rehydration rate, texture characteristics and hot air-drying characteristics were measured. Results: The optimum process parameters for the potato-oatmeal noodles were as follows: 53% water addition, mixing for 10 min, maturing for 40 min and steaming for 12 min. Based on the drying model, the optimum drying conditions were determined to be 40 min at 90 ℃. Conclusion: The potato-oat instant noodles prepared under the above optimal process conditions are shiny and elastic, soft and firm without sticking to the teeth and have a good taste.

The meteorological causes of wind deflection and tower collapse of a 500 kV transmission lines are analyzed. The wind speed distribution characteristics in the fault area of the line are obtained by using the observed wind speed of an automatic weather station and the three-dimensional wind field based on radar inversion. The results show that the maximum wind speed and the extreme wind speed observed by automatic weather stations around the two accidents are small. The three-dimensional wind field of radar inversion better indicates the fault's location and time. Compared with strong convective weather which can cause the wind deflection， the strong convective weather which can cause the tower collapse has a higher echo height and stronger updraft. The core height of its reflectivity factor drops more than 3.5 km within 6 minutes， causing greater ground damage， but its locality is strong and the influence range is small. The results show that the current design wind speed of the transmission line is safe under the strong convective weather that causes wind deflection， but adverse terrains that can accelerate the wind speed must be avoided. It is suggested to take “cascaded collapse prevention” as the main idea for the microburst which can cause the tower collapse. In addition， under the influence of strong convective weather， the gust coefficient calculated by the observed wind speed is significantly larger than the value in the relevant specifications.

Wetland restoration projects represented by ecological water conveyance have been widely used in the inland watersheds in northwest China. The interaction between groundwater and wetland vegetation under the ecological water conveyance determines the evolution of wetland ecosystems. In this study, the Qingtu Lake Wetland of the Shiyang River Basin in northwest China is taken as the research area, and the groundwater dynamic change and wetland vegetation restoration under the condition of the ecological water conveyance are analyzed based on a multi-element integrated monitoring network of groundwater-wetland ecosystem, combining with technologies of stable isotopes and satellite remote sensing. The purpose of this work is to reveal the co-evolution mechanism of groundwater and wetland ecosystems from the perspective of hydrogeology. The results show that the lake water recharges groundwater and the soil moisture increases during the ecological water delivery in late summer and autumn (the maximum soil moisture of observation sites is 0.45 m3/m3). In winter, this recharge decreases with the freezing of lake and surface soil. The thawing of frozen soil and lake in spring leads to a slight recovery of groundwater and an increase in soil moisture. In summer, the lake surface and the groundwater level are the smallest before the next ecological water delivery (the minimum surface area is about 1 km2, and the maximum groundwater depth of observation sites is 3.6 m). Meanwhile, the surface soil moisture is also the lowest (the minimum soil moisture of observation sites is 0.01 m3/m3), and the groundwater recharges the lake in some areas. The ecological water conveyed in late summer and autumn can act on vegetation recovery and growth in the following year by storing the water in groundwater and soil. Increasing the lake surface area formed by ecological water is helpful in upgrading vegetation coverage (the average correlation coefficient is 0.655). The soil water environment formed by the interaction of surface water-soil-groundwater is the main factor affecting vegetation types, root distribution and water use strategy. It is mainly controlled by the groundwater depth. With the increasing groundwater depth, the vegetation types and root depths increase, and the vegetations tend to use deep soil water. The research results can provide a scientific basis for the restoration of wetland ecosystems and efficient use of water resources in the northwestern inland basins.

The purpose of this paper was to prepare a sturgeon cartilage product from sturgeon cartilage and explore its effect on inflammation of human chondrocytes. A kind of sturgeon cartilage product was prepared by thermal liquefaction of sturgeon cartilage and dragon tendon at high temperature and high pressure. The optimum preparation conditions were determined by single factor and orthogonal test. Human chondrocytes were cultured by preparing drug-containing serum and the effects of sturgeon cartilage products on Interleukin 1β (IL-1β)-induced cell inflammatory model were investigated by MTT, Alsinland staining and ELISA. The results showed that the best preparation conditions of sturgeon cartilage products were as follows: Hot liquefaction temperature was 120 ℃, hot liquefaction time was 20 min, boiling temperature was 80 ℃, boiling time was 30 min. Under this condition, the sensory score of the product was 59.69. The drug-containing serum of sturgeon cartilage products group had no cytotoxicity and could stimulate chondrocytes to secrete collagen and proteoglycan and other extracellular matrix. Meanwhile, the product could significantly increase the proliferation activity of inflammatory cells by 156% (P

The COVID-19 pandemic brings about influence and challenge for ensuring healthcare services for non-communicable diseases. To guarantee the healthcare services for community-living patients with non-communicable diseases and to meet their healthcare needs, the Beijing municipal government issued a series of policies and relevant supporting measures, including five parts: promoting the implementation of the extended prescription policy, providing Internet-based medical services, further implementing the hierarchical medical system, giving full play to the role of family doctors, and carrying out the service of doorstep delivery of medicines. We reviewed and summarized policies and corresponding measures implemented in Beijing for guaranteeing healthcare for community-dwelling non-communicable disease patients during COVID-19 early response period and ongoing containment period. By evaluating the implementation effect of the policies and comparing with those at home and abroad, it is found that the community chronic disease management under the continuous epidemic situation can be further optimized in the future from the aspects of strengthening the training of grass-roots medical personnel, paying attention to the monitoring of chronic diseases and their risk factors, accurate health management, continuing to implement the hierarchical diagnosis and treatment system, and exploring the whole cycle health management of chronic diseases.

The current mining mode of rare earth mines in southern China is still the in-situ leaching mode. For this mining mode, the fractured structures, underground rivers, karst and other unfavorable geological bodies developed underground in the mine will seriously reduce the recovery rate of the leaching liquid. The leaching liquid leaking along the bad geological bodies will cause serious pollution to the environment, so it is of great significance to investigate the development status of the bad underground geological bodies in the mine. Based on the stratum distribution and structural characteristics of the C2 mining area of a rare earth mine in the south, this article first carried out high-density electrical method parameter experiments, selected appropriate measurement parameters and the Wenner-Schlumberg 2 device measurement mode, and completed the high-density of 4 survey lines Electrical measurement; the hidden electrical structure model of the study area is obtained through inversion calculation, the thickness of the weathered layer (stratum rich in rare earth minerals) and the spatial distribution characteristics of the hidden fault structure are delineated, the results are interpreted and the drilling of the study area layout The results are consistent. The exploration results provide important reference materials for the reserve evaluation of ionic rare earth ore, the plugging of seepage channels, and the layout of liquid collection roadways.

An elderly woman with a chronic course of disease presented with progressive weakness of lower limbs, heart failure, carbon dioxide retention, periorbital pigmentation, increased hair around the eyebrows, as well as multiple positive autoantibodies. After multidisciplinary team discussion, restrictive ventilatory dysfunction caused by significantly decreased diaphragm movement was taken as a breakthrough to sort out the etiology step by step. Based on clinical manifestations, serological and imaging features, as well as immunohistochemical staining of quadriceps femoris pathological complement, the final diagnosis of inflammatory myopathy associated with anti-mitochondrial antibodies was established. After correcting heart failure, intermittent non-invasive ventilation and rehabilitation training, clinical symptoms and functional status of the patient were significantly improved. The joint participation of the multidisciplinary team to identify the causes and solve problems in diagnosis and treatment decision-making reflects the great significance of multidisciplinary collaboration in rare diseases.

The vortex ElectroMagnetic (EM) wave has a unique spiral phase wavefront. The rotational Doppler effect, induced by the lateral micromotion of a target is expected to provide a new mode of radar target detection. Under the illumination of vortex EM waves, the micromotion of a cone-shaped target periodically modulates the instantaneous frequency of the radar echo; this can effectively reflect the geometric characteristics and micromotion parameters of a cone-shaped target. This paper focuses on the estimation of cone-shaped target parameters under forward-looking radar conditions. First, based on the principle of vortex EM wave target rotational Doppler detection, a mathematical equation describing the vortex EM wave of a cone-shaped target echo is derived, and an echo rotational Doppler model is established. Second, a method for cone-shaped target parameter estimation under forward-looking conditions is proposed. Using the two-dimensional rotational Doppler information of the scattering points at the top and bottom of a cone-shaped target, the micromotion and geometric parameters of the target can be effectively estimated. The simulation results verify the effectiveness and robustness of the method proposed in this paper.

The vortex ElectroMagnetic (EM) wave, whose phase wavefront is modulated by the Orbital Angular Momentum (OAM), has received immense attention, especially in the field of forward-looking radar imaging. Based on the fundamental principle and imaging method of the vortex EM radar, the azimuth resolution was studied in this paper. First, the circumstance of considering the Bessel amplitude term was analyzed, indicating that the azimuth resolution was determined by the effective scope of OAM modes. Then, an effective method for calculating the scope of OAM modes was proposed, including the expressions of azimuth resolution, spatial resolution, and super-resolution were characterized. Finally, the fundamental resolution performance with different influencing factors was analyzed via simulations. The analysis showed that changing the wavelength aperture ratio and imaging elevation could increase the effective scope of OAM modes, which improved the azimuth resolution. Through data fitting, the approximate expressions of the effective scope of OAM modes and the resolution of the super-real aperture radar with respect to the wavelength aperture ratio and imaging elevation were obtained separately, providing a reference for the parameters design and optimization of vortex EM wave radar.

Terahertz vortex beams can be used to improve the communication capacity of radar communication systems and the resolution of imaging systems. This paper presents a deflective vortex beam generation method based on a reflective metasurface working in the terahertz band. Without the limitations of traditional methods, metasurfaces are a good candidate to generate beams carrying an orbital angular momentum in the terahertz band. First, we designed and simulated a unit cell of the metasurface. The unit cell of our design consists of two metallic (gold) layers and one dielectric layer. An almost 360° phase shift was acquired by adjusting the length of the eight stubs of the top layer. The unit cell of the metasurface was simulated by CST Microwave Studio, and the simulation results showed that the co-polarization reflection efficiencies of the unit cells were more than 90%. To avoid performance degradation due to blockage of the feed horn, we controlled accurately the directions of vortex beams based on the concept of reflectarray. To verify the performance of our design, we simulated and measured five reflective metasurfaces. The results of simulation and measurement showed that these metasurfaces could generate five deflective vortex beams in the terahertz band. The topological charges of these beams are ±1, ±2, and 3, which account for the highest energy proportion in different vortex beams.

BackgroundCompared with 2D+1D adjustment, three dimensional adjustment has a more rigorous theoretical basis. However, when the unconstrained three dimensional adjustment is applied to the observation values processing of the accelerator alignment control network, serious error accumulation will occur and resulting in obvious distortion of the results.PurposeThis study aims to expound the ways and characteristics of three dimensional adjustment error accumulation for accelerator alignment control network.MethodsFirstly, based on the layout of accelerator alignment control network and the moving station measurement method of laser tracker, the three dimensional adjustment mathematical model was analyzed, and the least-squares collocation theory was used to clearly explain the error propagation. Secondly, the characters of laser tracker measurement accuracy, station positioning and orientation accuracy and single station measurement error propagation were studied by analyzing the laser tracker 3D coordinate measurement model, measurement point error model and simulation measurement experiments. Finally, adjustment calculation of the linac control network was verified by simulation measurement, and two error accumulation suppression methods were tested.ResultsThe source and propagation mode of error accumulation are explained theoretically, and verified by simulation calculation, so are the serious error accumulation of elevation and lateral errors in three dimensional adjustment of control network in accelerator.ConclusionsProviding high-precision point coordinate constraint for three dimensional adjustment can effectively suppress error accumulation, and providing high-precision orientation constraint for station coordinate system can also achieve the effect of suppressing error accumulation.

The load sharing characteristics of a planetary gear train is one of its main performance. Many researches at home and abroad have shown that the floating effect of components in a planetary gear train has an important influence on load sharing characteristics of the system. In this paper,the relationship between sun gear and spline on the input shaft is considered. Also,friction of inner and outer teeth in splined connection as well as constraint floating of sun gear are simulated. The nonlinear opposite supporting force of the spline on the input shaft to the sun gear is established. Taken a 5-planetary gear transmission system as an example,its load sharing coefficients with different radial clearance of a spline are calculated by the lumped-mass method. The research result provides a basis for load sharing design of planetary gear trains.

The hexagonal wurtzite Gallium nitride(GaN) was prepared by calcining β gallium oxide(β-Ga2O3) in flowing ammonia. The XRD, SEM and TEM were employed to investigate the structure and morphology. The photoluminescence (PL) spectroscopy was used to collect photoluminescence spectroscopy of GaN perform the luminous property. The measurement results revealed that the obtained GaN had preferred orientation of (002), and the rod shape and grain size of GaN powders were similar to those of raw gallium oxide which were agglomerates of tens nanometers flake crystallites. The near-edge emission at 346 nm(3.584 eV) of Gallium nitride powders had a blue shift of 19 nm(187 meV) than that of bulk GaN material. [ABSTRACT FROM AUTHOR]

A 3x2 factorial design of microcosm experiment was conducted to investigate the interactive effects of straw, nitrogen fertilizer and bacterivorous nematodes on soil microbial biomass carbon (Cmic) and nitrogen (Nmic), dissolved organic carbon (DOC) and nitrogen (DON), mineral nitro- gen (NH4+-N and NO3--N), and greenhouse gas (CO2, N2O and CH4 ) emissions. Results showed that straw amendment remarkably increased the numbers of bacterivorous nematodes and the contents of Cmic and Nmic, but Cmic and Nmic decreased with the increasing dose of nitrogen fertilization. The effects of bacterivorous nematodes strongly depended on either straw or nitrogen fertilization. The interactions of straw, nitrogen fertilization and bacterivorous nematodes on soil DOC, DON and mineral nitrogen were strong. Straw and nitrogen fertilization increased DOC and mineral nitrogen contents, but their influences on DON depended on the bacterivorous nematodes. The DOC and mineral nitrogen were negatively and positively influenced by the bacterivorous nematodes, respectively. Straw significantly promoted CO2 and N2O emissions but inhibited CH4 emission, while interactions between nematodes and nitrogen fertilization on emissions of greenhouse gases were obvious. In the presence of straw, nematodes increased cumulative CO2 emissions with low nitrogen fertilization, but decreased CO2 and N2O emissions with high nitrogen fertilization on the 56th day after incubation. In summary, mechanical understanding the soil ecological process would inevitably needs to consider the roles of soil microfauna. [ABSTRACT FROM AUTHOR]