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The conventional pretreatment methods for mine water generally include coagulation, sedimentation (flotation), and filtration. However, large equipment footprint, long processing time and pollution from coagulants and flocculants have been limiting the further development of underground mine water treatment. In this light, we designed an underground mine water pretreatment device based on ultrasonic atomization for clarifying and pre-softening mine water so that the turbid mine water could be treated to meet the needs of underground production, firefighting, and dust reduction. We conducted indoor experiments on mine water clarification and pre-softening treatment using water and rock samples from the field mined-out area. The results show that: (1) This method can clarify black-gray turbid mine water with a large amount of solid impurities, effectively removing insoluble solid impurities in the water. (2) Ultrasonic atomization reduces the total hardness of the water by 72.24%. The milligram equivalent concentration of Ca2+ is reduced from 5.33 mg/L to 0.81 mg/L and the milligram equivalent concentration of Mg2+ drops from 5.23 mg/L to 2.13 mg/L, with little impact on pH. (3) The water from the mined-out area after ultrasonic atomization can meet the requirements of sprinkling in underground firefighting, spraying in dust reduction, the mining process of coal mining equipment, and the use of cooling water.

The hot deformation behavior and dynamic recrystallization of Al-11.1Zn-2.3Mg-2.0Cu-0.05Sc alloy was explored in the isothermal hot compression test with a temperature range of 653-733 K at strain rate of 10-3 s-1. The microstructural evolution of the studied alloy at different temperatures was analyzed by EBSD technology. The dynamic recrystallization（DRX） critical strain， critical stress， fraction， and average grain size equations were established by linear regression. The results show that the fitted equations can accurately describe the DRX characteristics of the studied alloy during hot deformation.The increase in the deformation temperature enlarges the misorientation angle inside the grains， which facilitates the DRX progress. The distributions of crystal orientation tend to be more homogeneous with the increase in temperatures. Moreover， dynamic recovery is the dominant dynamic softening mechanism. With the temperature change， there are three types of recrystallization mechanisms in the microstructure of aluminum alloy， including discontinuous dynamic recrystallization， continuous dynamic recrystallization， and geometric dynamic recrystallization.

IntroductionThe main gate valve is a critical component of the coolant system in marine nuclear power plants, yet its integrity is often compromised by leakage, particularly during transient operations. This study employs a fluid-solid-thermal coupling method to numerically investigate the sealing performance of the main gate valve under rapid coolant temperature drops.MethodsThe analysis reveals that thermal shock-induced uneven stress and deformation significantly reduce contact pressure on the sealing surface, leading to leakage.Results and DiscussionNotably, only when the bolt preload reaches the material yield limit can the valve maintain a seal during operation. Furthermore, the study demonstrates that a faster rate of coolant temperature drop exacerbates the leakage. These findings offer valuable insights for optimizing the operation of marine nuclear power plants and enhancing the structural integrity of the main gate valve.

Abstract Background The cardiac toxicity of radiotherapy (RT) can affect cancer survival rates over the long term. This has been confirmed in patients with breast cancer and lymphoma. However, there are few studies utilizing the two-dimensional speckle-tracking echocardiography (2D-STE) to evaluate the risk factors affecting radiation induced heart disease (RIHD), and there is a lack of quantitative data. Therefore, we intend to explore the risk factors for RIHD and quantify them using 2D-STE technology. Methods We ultimately enrolled 40 patients who received RT for thoracic tumors. For each patient, 2D-STE was completed before, during, and after RT and in the follow up. We analyzed the sensitivity of 2D-STE in predicting RIHD and the relationship between RT parameters and cardiac systolic function decline. Results Left ventricle global longitudinal strain (LVGLS), LVGLS of the endocardium (LVGLS-Endo), LVGLS of the epicardium (LVGLS-Epi), and right ventricle free-wall longitudinal strain (RVFWLS) decreased mid- and post-treatment compared with pre-treatment, whereas traditional parameters such as left ventricular ejection fraction (LVEF), cardiac Tei index (Tei), and peak systolic velocity of the free wall of the tricuspid annulus (s’) did not show any changes. The decreases in the LVGLS and LVGLS-Endo values between post- and pre-treatment and the ratios of the decreases to the baseline values were linearly correlated with mean heart dose (MHD) (all P values < 0.05). The decreases in the LVGLS-Epi values between post- and pre-treatment and the ratios of the decreases to the baseline values were linearly correlated with the percentage of heart volume exposed to 5 Gy or more (V5) (P values < 0.05). The decrease in RVFWLS and the ratio of the decrease to the baseline value were linearly related to MHD and patient age (all P values < 0.05). Endpoint events occurred more frequently in the right side of the heart than in the left side. Patients over 56.5 years of age had a greater probability of developing right-heart endpoint events. The same was true for patients with MHD over 20.2 Gy in both the left and right sides of the heart. Conclusions 2D-STE could detect damages to the heart earlier and more sensitively than conventional echocardiography. MHD is an important prognostic parameter for LV systolic function, and V5 may also be an important prognostic parameter. MHD and age are important prognostic parameters for right ventricle systolic function.

Background Medical work is characterized as challenging, tasking and stressful. The effort-reward imbalance (ERI) model suggests that if the organizational environment contributes to ERI, it can negatively affect employees. The investigation of medical staff is an important part of the 6th National Health Services Survey in 2018. The good job satisfaction and work conditions of medical staff are important determinants of service utilization and health improvement for the population. The sense of accomplishment and satisfaction of medical staff is also an important goal of the new healthcare reform. Objective To explore the relationship between ERI and job stress, and provide a reference for reducing the job stress of medical staff. Methods The data for this study were obtained from the results of a sample survey of 4 156 healthcare workers in Beijing during the 6th National Health Services Statistics Survey in 2018. A predictive structural equation model of job stress was constructed and based on ERI questionnaire and job stress questionnaire. Relevant parameters were estimated by using the partial least squares to analyze the relationship between ERI and job stress. Results The valid records for participating in the ERI index calculation were 4 098. According to the ERI index calculation results, 1 333 (32.53%) healthcare workers were in a state of balance between effort and reward, and 2 765 (67.47%) health workers were in a state of imbalance between effort and reward. The results of factor analysis showed that 46.00% of the job stress experienced by medical staff in Beijing can be attributed to ERI model. Extrinsic, intrinsic effort and work reward all had a direct impact on job stress (P

Background: Incidental gall bladder cancer (IGBC) is often discovered unexpectedly in patients after cholecystectomy. Currently, magnetic resonance imaging (MRI) has been widely applied in the pre-operative diagnosis of gall bladder diseases as laparoscopic cholecystectomy developed into the preferred method. Aims and Objectives: This study aimed to evaluate the pre-operative MRI application and laparoscopic management in the IGBCs. Materials and Methods: Between January 2011 and January 2020, a total of 7917 patients with gall bladder diseases treated by laparoscopy were enrolled in this study. Results: Amongst 49 patients diagnosed with IGBCs, the incidence of IGBCs in polypoid lesions, biliary pancreatitis, cholecystitis, cholecystocholedocholithiasis and gall bladder stones was 0.42%, 1.19%, 0.62%, 1.20% and 0.49%, respectively. MRI evaluation showed more remarkable pre-operative imaging as compared to ultrasonographic evaluation (40.8 vs. 26.5, P < 0.05). Furthermore, 14 patients were diagnosed with gall bladder cancer through intraoperative histological examination and 11 received laparoscopic extensive resection after cholecystectomy. MRI findings with diffuse thickening of the gall bladder detected IGBCs with 6.1% sensitivity, 96.02 specificity, 0.95% positive predictive values and 99.4% negative predictive values; diffuse thickening of the gall bladder with suspicion of malignancy detected IGBCs with 12.2% sensitivity, 99.1% specificity, 7.6% positive predictive values and 99.5% negative predictive values; focal thickening of the gall bladder detected IGBCs with 16% sensitivity, 99.8% specificity, 32% positive predictive values and 99.5% negative predictive values; moreover, suspicious lesion detected IGBCs with 6.1% sensitivity, 99.6% specificity, 8.8% positive predictive values and 99.4% negative predictive values. Conclusions: Patients with biliary pancreatitis and cholecystocholedocholithiasis have a higher incidence of IGBC. MRI evaluation could provide more accurate information for the IGBCs, which should be recommended for patients accepting cholecystectomy. MRI findings exhibited an unsatisfactory sensitivity when detecting IGBCs, but they represented high specificity. Pre-operative MRI evaluation and intraoperative histological examination may help some IGBCs to achieve one-stage laparoscopic extensive resection.

Objective With the rapid increase in construction projects in the western regions in recent years, the impact of seasonal freeze-thaw cycles in the high-altitude areas of western China has become more pronounced. Conducting research on the microscopic characteristics and strength degradation properties of rocks under freeze-thaw cycles is crucial for guiding engineering construction in these cold, high-altitude regions. Methods To study the influence of freeze-thaw cycles on rock structure and mechanical properties, we collected diorite samples from a tunnel in the Kangding area and examined the effects of freeze-thaw cycles on their microstructure and mechanical characteristics. Firstly, thin rock sections were observed under a polarizing microscope to obtain mineral compositions and microstructures. Then, CT scanning technology was used to scan the granite samples after freeze-thaw cycles, and the scanned layers were binarized using threshold segmentation. The scanning images of different layers were binarized using threshold segmentation, and high-resolution 3D data and images of the internal and external structures of the samples were obtained by stacking the binary image layers. Fractal theory was applied to calculate the box-counting dimension of the images and quantitatively assess their complexity. This analysis allowed us to examine the evolution and distribution characteristics of the internal structure of granite under freeze-thaw cycles. Results Under a polarizing microscope, the rock exhibits a block-like structure with a patchy, coarse-grained, and unequal-grained granite texture, with locally visible metasomatic worm structures. The main phenocryst minerals are alkaline feldspar. Other minerals range in size from 0.25 to 4.0 mm and primarily include quartz, plagioclase, and alkaline feldspar. Secondary minerals include biotite and epidote, while accessory minerals comprise apatite, zircon, and pyrite. Microscopically, the rock is identified as porphyritic, coarse-grained, and unequal-grained biotite diorite granite. Freeze-thaw cycles were applied to the granite samples in the laboratory to study the strength evolution and explore the relationship between structural evolution and strength. The results indicate that the freeze-thaw cycle effect leads to an overall increase in the internal porosity of the granite's microstructure, though the rock's permeability changes minimally, with an increase of only 0.003×10−3 μm2. The internal pore development is uneven, primarily due to the emergence of new micropores, causing changes in the overall structure of the sample. After freeze-thaw cycles, the complexity of the internal structure of the rock decreases, but the overall integrity remains good, with the fractal dimension staying at a high level. Fractal analysis shows that 20 freeze-thaw cycles do not cause significant changes in the structural complexity of granite. However, the overall mechanical properties of the sample decline, viscosity increases, and long-term strength shows significant attenuation, raising the strain threshold for entering the creep test stage. Conclusion When evaluating the safety of rocks with dense primary structures, considering only their structure may lead to deviations from the actual situation. It is essential to combine necessary strength indicators for a comprehensive evaluation. After undergoing freeze-thaw cycles, rocks tend to exhibit more significant deformation while maintaining lower strength. Therefore, appropriate treatments are required for construction in high-altitude areas. [ Significance ] This study provides a reference for applying fractal theory to the evolution of rock microstructure and the relationship between rock microstructure and strength evolution. It also offers valuable guidance for engineering construction in high-altitude and cold regions.

The existing intelligent optimization algorithm of air volume of mine ventilation network has the defects of complex model, slow convergence speed, easy falling into local optimum when solving the air adjustment parameters. There is a lack of research on the combination of optimal selection of air adjustment branches. To solve the above problems, an intelligent control method of air volume of mine ventilation network based on improved beetle antennae search (BAS) algorithm is proposed. Firstly, the mathematical model of air volume optimal adjustment is established by taking the air volume demand of the air consumption branch as the optimization objective. In view of the air volume adjustment constraint conditions in the model, the non-differentiable exact penalty function and the simulated annealing algorithm are adopted to optimize the penalty term, so that the model is unconstrained. Secondly, by solving the sensitivity matrix and combining the theory of air volume sensitivity and branch dominance, the optimal adjustment branch set is selected. The air resistance adjustment range is determined as the initial solution set of the model. Finally, based on the improved BAS algorithm, the optimal air adjustment parameters are solved. The corresponding air adjustment facilities are controlled to realize air volume adjustment. The reliability of the method is verified by experiments based on the mine ventilation experimental platform. The results show that compared with the standard BAS algorithm and particle swarm optimization (PSO) algorithm, the improved BAS algorithm has superior comprehensive optimization performance. The average value and optimal solution of air volume are higher than those of the PSO algorithm and standard BAS algorithm. Although the average running time is slightly longer than the standard BAS algorithm, it is far shorter than the PSO algorithm. The average convergence algebra is the most, the precision is the highest, and it is easy to jump out of the local loop to get the optimal solution. After setting the air volume adjustment target, the intelligent control method of air volume of the mine ventilation network based on the improved BAS algorithm can quickly and accurately solve the optimal value of the air volume of the branch to be adjusted. The adjusted branch air volume meets the air volume adjustment requirements of mine safety production, and the air volume is increased up to 46.5%.

ObjectiveTo analyze the effectiveness and safety of clinical use of different types of stem cells to provide evidence for governmental supervision of key issues in clinical utilization of stem cells.MethodsSix literature databases in China and abroad were searched for relevant literature published from January 2010 to July 2020， and a systematic review was conducted.ResultsThe study showed 72 studies concerning the effectiveness and safety of different types of stem cells in clinical utilization. Although clinical utilization of stem cells had some therapeutic effects for certain diseases， their long-term effect and safety need to be further evaluated， especially their potential risk of tumorigenicity.ConclusionTo protect the patients’ interest， physicians should fully weigh the benefits against the risks of clinical utilization of stem cells， and relevant governmental departments should strengthen supervision of ethics of clinical research and therapies involving stem cells as well as supervision of stem cell products.

In the paper， national and international ethical requirements and supervision on stem cell research and clinical application were analyzed after literature review. It is suggested that the development of stem cell technology should be timely tracked， prospective ethical research related to stem cells should be enhanced， and that stem cell research and clinical translation should comply with relevant international ethical guidelines and national regulations in China. In addition， it is indicated that the oversight of stem cell products and their clinical use will be continuously improved in our country.

Aiming at the shortcomings of the current coal mine explosion venting devices, a new explosion venting door is designed, and its structure, explosion venting mechanism and beneficial efficiency enhancement are discussed. FLUENT software was used to simulate gas explosion under different working conditions and the change laws of explosion pressure, flame temperature and flame speed were analyzed by monitoring, and the explosion venting effect of the explosion vent door was verified. The results show that when the gas mass fraction is 9.5%, it is found that the explosion pressure peak generated by the explosion-proof wall is the largest, and the pressure is maintained at 0.29 MPa after attenuation, and the surrounding rock and equipment in the roadway are continuously damaged under high-pressure environment. The explosion venting door can quickly release the pressure, so that the fire area can be closed without fresh air, and reduce the occurrence of secondary explosions and secondary disasters. Under the working condition of gas mass fraction 5.5%-11.5%, the overall change law of gas explosion characteristic parameters is the same. As the gas volume fraction increases, the gas explosion characteristic parameters first increase and then decrease. The explosion venting capacity of the explosion venting door has nothing to do with the gas volume fraction, however the gas volume fraction changes, the pressure is released and the fire area is closed at the same time.

Li Ang et al. present an investigation of feral and domesticated horse gut microbiomes across three continents. Their results provide new insight into how changes in horse lifestyle are reflected in the resident gut microbiome.

BackgroundThe optimal treatment for elderly patients with severe heart failure depends on the accurate assessment of their hemodynamic status. Due to its less invasive nature, the safety and efficacy of invasive pulse-induced contour cardiac output (PiCCO)-based hemodynamic monitoring remains uncertain.MethodsThis was a prospective observational study. Between January 2016 and July 2020, 190 elderly patients with severe heart failure were consecutively enrolled. The PiCCO group (89 patients) and non-invasive hemodynamic monitoring group (101 patients) were observed. Hospital stays results were evaluated.ResultsNo significant difference in clinical data (P > 0.05) or the incidence of 1-month mortality (16.0 vs. 35.0%, P = 0.141) were observed between groups. The coronary care unit (CCU) stay was shorter in the PiCCO group than in the non-invasive group (40.0 vs. 43.0%, P = 0.049). Indicators such as low Extravascular Lung Water Index (EVLWI), high Body Mass Index (BMI), low Pulmonary Artery Pressure (PAP), and high Left Ventricular Ejection Time (LVET), were associated with favorable clinical results.ConclusionEarly invasive PiCCO monitoring is safe in critically ill elderly patients with severe heart failure. The hospital stay was reduced using PiCCO monitoring. These encouraging PiCCO results favor its use in elderly patients with severe heart failure at CCUs.

Most of the existing mine ventilation system health evaluation methods use constant weights. The evaluation results easily deviate from the actual situation and cannot reflect the real state of the system. At the same time, there are many indexes selected, and the weight of each index is low, which makes it difficult to detect the impact of some indexes abnormalities on the overall health of the system. Based on the actual operating conditions and health evaluation requirements of mine ventilation system, 21 influencing factors are selected as the health evaluation indexes to construct the health evaluation index system of mine ventilation system. Fuzzy comprehensive evaluation, analytic hierarchy process and variable weight theory are used comprehensively to carry out the health evaluation of mine ventilation system. The analytic hierarchy process is used to determine the weights of evaluation indexes, the Hardarmard product variable weight model based on membership degree is used to calculate the index weights. The maximum membership degree criterion of fuzzy comprehensive evaluation is used to determine the health degree of mine ventilation system. This method is used to evaluate the health of a coal mine ventilation system. The results show that the evaluation result of this method is consistent with the actual situation. Compared with the evaluation method based on constant weight, the weights of the evaluation index of this method can be adjusted according to the actual situation so as to make the evaluation result more objective. Moreover, this method amplifies the impact of unhealthy indexes and highlights the potential system safety hazards, which attracts the attention of relevant personnel.

To reduce the vibration damage to the riser, hydrodynamic parameters of a smooth riser and a riser with triple symmetrically distributed helical strakes are evaluated in an experiment. The wave and current in natural environment are conceptualized to the experimental condition of the oscillatory flow and the uniform flow. Experiment cases are divided into the static flow and the uniform flow, while the risers oscillate along the in-line, the transverse, and the diagonal direction. The added mass coefficient Cm and the drag coefficient Cd are calculated from experimental data by using the Morison equation. The results of the riser with strakes indicate that Cm is independent of the Keulegan-Carpenter (KC) number and the oscillating direction. Cd is found to be in inverse proportion to the ratio of 1/3 power of the KC number and the maximum flow speed to oscillatory velocity. This finding is consistent with the format of Morison parameters of a flat plate in oscillatory flow, which endows the classical theory with novel validation and implication in the design of a riser. Under the same condition, the Cd of the helical strake riser is promoted over 273% than the bare riser, which indicates that the helical strakes efficiently reduce the influence of oscillation under complex conditions. The results provide a new solution for vibration reduction of offshore structures, which is of high value in ocean engineering.

PurposeIn this study, we examined the changes to the composition and function of the gut microbiota from patients with metabolic dysfunction-associated fatty liver disease (MAFLD).We compared patients in a case group (liver stiffness (LSM) ≥ 7.4 kPa) with a matched control group (LSM < 7.4 kPa) and investigated the correlation between characteristics of the microbiota and other biochemical indicators. MethodsThe study looked at a total of 85 men with MAFLD, 17 of whom were in the case group and 68 of whom were in the control group. We measured waist circumference, blood pressure, and body mass index, as well as clinical parameters including liver stiffness, enzyme levels, cholesterol levels, and fat attenuation. Whole-genome shotgun sequencing technology and the MetaCyc database were then used to detect the composition and major pathways of the gut microbiota for each patient. Statistical analyses were performed, including the chi-square test, the student’s t-test, the Wilcoxon rank-sum test, and the Mann–Whitney test. ResultsWhole-genome sequencing showed that the composition of the gut microbiota in patients with an LSM of above 7.4 kPa was significantly different to that of the control group. There were seven bacterial species that were different between the two groups. Prevotella copri, Phascolarctobacterium succinatutens, Eubacterium biforme, and Collinsella aerofaciens were enriched in the case group (P < 0.05). Conversely, Bacteroides coprocola, Bacteroides stercoris and Clostridiales bacterium 1_7_47FAA were decreased in the case group (P < 0.05). Furthermore, after removing low abundance pathways, a total of 32 microbial pathways were found to be significantly different between the two groups. Most pathways enriched in the case group over the control were related to biosynthesis of metabolites including amino acids, vitamins, nucleosides, and nucleotides. Conclusion. The composition and function of the gut microbiota in patients with increased liver stiffness are significantly altered. This observation may provide new avenues to better understand the mechanism of liver fibrosis.

IntroductionTargeted therapies for sepsis have failed to show benefit due to high variability among subjects. We sought to demonstrate different phenotypes of septic shock based solely on clinical features and show that these relate to outcome.MethodsA retrospective analysis was performed of a 1,023-subject cohort with early septic shock from the ProCESS trial. Twenty-three clinical variables at baseline were analyzed using hierarchical clustering, with consensus clustering used to identify and validate the ideal number of clusters in a derivation cohort of 642 subjects from 20 hospitals. Clusters were visualized using heatmaps over 0, 6, 24, and 72 h. Clinical outcomes were 14-day all-cause mortality and organ failure pattern. Cluster robustness was confirmed in a validation cohort of 381 subjects from 11 hospitals.ResultsFive phenotypes were identified, each with unique organ failure patterns that persisted in time. By enrollment criteria, all patients had shock. The two high-risk phenotypes were characterized by distinct multi-organ failure patterns and cytokine signatures, with the highest mortality group characterized most notably by liver dysfunction and coagulopathy while the other group exhibited primarily respiratory failure, neurologic dysfunction, and renal dysfunction. The moderate risk phenotype was that of respiratory failure, while low-risk phenotypes did not have a high degree of additional organ failure.ConclusionsSepsis phenotypes with distinct biochemical abnormalities may be identified by clinical characteristics alone and likely provide an opportunity for early clinical actionability and prognosis.

The current study was aimed to examine the effect of partial or complete replacement of fishmeal (FM) with fermented soybean meal (FSBM) on growth performance, fecal composition, and meat quality in broiler chickens. A total number of 240 one-day-old broiler chicks were randomly allotted into four dietary treatments with six replications and ten birds per one pen. Dietary treatments were followed as; 1) Diet incorporated with 4% FM without FSBM (Control), 2) Diet incorporated with 3% FM and 2% FSBM (FSBM2), 3) Diet incorporated with 2% FM and 3% FSBM (FSBM3) and 4) Diet incorporated with 4% FSBM without FM (FSBM4). Body weight and feed intake were recorded weekly for 35 days of the experimental period. Moreover, fecal samples were collected to evaluate moisture, ash, nitrogen, calcium and phosphorus content on day 21 post-hatch. On day 35, two birds were sacrificed from each pen to measure meat quality parameters and visceral organ weights. Results revealed that, no dietary treatment effect (p > 0.05) was observed either in both body weight or average daily gain of broilers within the entire experimental period while broilers fed FSBM2 increased (p < 0.05) average daily feed intake by 10.07% whereas FSBM4 improved (p < 0.05) feed efficiency ratio by 8.45% compared to birds fed other dietary treatments on day 7 post-hatch. Besides, birds fed FSBM3 obtained the improved (p < 0.05) feed conversion ratio over the birds fed control diet by 7.51% from hatch to day 35 post-hatch (1.60 vs. 1.73). Nevertheless, no difference (p > 0.05) was detected on visceral organ weight, proximate composition and physicochemical characteristics of meat while broilers offered FSBM4 obtained the lowest (p < 0.05) calcium and phosphorous in faces (2.27% and 1.21% respectively) over those offered control feed and other FSBM treatments. In conclusion, FSBM would be a better replacement for ousting FM partially or completely in broiler diet as it did not impair the growth performance and meat quality while reducing the calcium and phosphorous excretion in broilers for 35 days post-hatch.

Gestational thrombocytopenia (GT) is the most common cause of thrombocytopenia during pregnancy. However, the occurrence and severity of thrombocytopenia throughout pregnancy in Chinese women are not fully defined.

In the operation of bolter miners, the cutting arm is an essential and weak part and its fatigue life directly affects its performance. This study aimed to investigate the influence of the cutting head load on the fatigue life of a cutting arm using the DEM-MFBD (Discrete Element Method-Multi Flexible Body Dynamics) bi-directional coupling technique. The EJM340 bolter miner was chosen as the research object, and a three-dimensional solid model of the bolter miner was built using the RecurDyn software. The cutting arm was flexibly modelled, and the tunnel model was built using the EDEM software. The motion parameters of the bolter miner and cutting head load were transferred through the bi-directional coupling interface to obtain the loads and stress parameters during the entire tunnel cutting process. Based on the stress-time variation, the fatigue life of the cutting arm was calculated, the overall damage and crack initiation locations were obtained, and the minimum number of cutting arm cycles was determined. The accuracy of the virtual model is verified through field experiments. The analysis results indicated that the crack emergence location and fatigue life obtained from the simulation were in agreement with the experimental results.

Davidia involucrata Baill. is a kind of tertiary paleotropical plant floristic relic species unique to China. This rare plant is disappearing due to poor adaptability and serious poaching. Davidia involucrata has been listed as a national first-level protected wild plant, a unique genus plant unique to China, a relic plant, and a well-known ornamental plant in the world. It is a national-level protected plant. In this study, the complete chloroplast genome sequence of D. involucrata was characterized from Illumina pair-end sequencing. The chloroplast genome of D. involucrata was 158,118 bp in length, containing a large single-copy (LSC) region of 87,329 bp, a small single-copy (SSC) region of 18,869 bp, and two inverted repeat (IR) regions of 25,960 bp. The overall GC content is 37.80%, while the corresponding values of the LSC, SSC, and IR regions are 36.0%, 31.6%, and 43.1%, respectively. The genome contains 132 complete genes, including 86 protein-coding genes, 38 tRNA genes, and eight rRNA genes. Phylogenetic analysis based on complete chloroplast genomes showed that D. involucrata and Camptotheca acuminate clustered together as sisters to other related species.

The longitudinal motion characteristics of a slender trimaran equipped with and without a T-foil near the bow are investigated by experimental and numerical methods. Computational fluid dynamics ( CFD) method is used in this study. The seakeeping characteristics such as heave, pitch and vertical acceleration in head regular waves are analyzed in various wave conditions. Numerical simulations have been validated by comparisons with experimental tests. The influence of large wave amplitudes and size of T-foil on the longitudinal motion of trimaran are analyzed. The present systematic study demonstrates that the numerical results are in a reasonable agreement with the experimental data. The research implied that the longitudinal motion response values are greatly reduced with the use of T-foil.

Metal additive manufacturing is a new type of material-forming technology characterized by its short process and near net shape. Equipment, material and process are critical factors which serve as the supporter, key, and foundation respectively in terms of the development of this technology. In this paper, the characteristics of the equipment, material, and process of the different representative technologies were summarized. The relations among metal additive manufacturing equipment, manufacturing material, and manufacturing process as well as their roles in the metal additive manufacturing technology were analyzed. The research status of the raw material supply system, forming system, and control system were reviewed. The typical microstructure and mechanical properties of metal additive manufacturing materials, such as titanium alloy, nickel alloy, aluminum alloy, and steel, were summarized. The effects of the manufacturing process parameters on residual stress, porosity, accuracy, and microstructure were discussed. Problems associated with the manufacturing equipment, such as high cost, limited forming size, and low forming efficiency were discussed along with the problems associated with the material, such as high production cost and poor applicability. Furthermore, problems associated with the metal additive manufacturing process, such as difficult matching of process parameters and severe thermal accumulation, were elaborated as well. Future developmental goals in metal additive manufacturing include: (a) reducing the cost of manufacturing equipment and material, (b) expanding the range of product forming size, (c) improving the product printing accuracy and forming efficiency, (d) expanding the types and application scope of metal additive manufacturing material, (e) reducing the difficulty in the matching of process parameters, (f) improving product quality and comprehensive performance, and (g) developing new types of metal additive manufacturing technologies.

The phase state of the dense stellar matter is an exciting topic in the area of nuclear astrophysics. It may be probed by observed properties of neutron stars from, for example, the currently operating satellites (NICER, Neutron star Interior Composition Explorer) and the gravitational-wave laser interferometers (Advanced LIGO, Virgo, and KAGRA). Based on our recent constrained parameter spaces of the equation of states of neutron stars and quark stars from LIGO/Virgo and NICER, we discuss the important role of an even-accurate determination of the stellar radius for distinguishing possible quark stars from neutron stars and our understanding of the QCD phase transition at finite density.

Understanding Indoor Airflow Patterns (IAPs) helps control air contaminants in large naturally ventilated buildings (NVBs). However, the effect of random and unpredictable changes in outdoor wind conditions (OWC) is a major contributor to the variation in IAPs in the NVBs, making the IAP uncontrollable. This study presents the results of field measurements and numerical simulation in a NBV to study the IAP variation characteristic under the dynamical OWC. The OWC data monitored in real time was processed with Kalman Filtering (KF) and the gradient method to decompose the data prior to being entered into the CFD solver. The trend was similar between the simulated and measured data of a full size NVB. In addition, the distribution of internal turbulence intensity varied widely depending on the spatial locations and time intervals. The variation in speeds in the vicinity of windbreaks greatly affected the variation in IAP on a certain frequency scale. The results not only prove that CFD simulation to be an efficient tool for the prediction of time-averaged IAP, but also initialize efficient measures for the control of IAQ in dynamic OWC of large space NVBs.

The heavy water condensation problem has led to safety concern for the workers and electrical facilities in the underground pumped storage power station. As for current dehumidification scheme, heat and humidity load are all removed through the air conditioning unit, which has high energy consumption and low efficiency. As a large amount of moisture comes from the external fresh air, in this study, we set the dehumidification system in the underground ventilation tunnel. By using the air inlet channel to lighten the wet load, the heat and humidity parameters of the fresh air are processed as far as possible in the front of the air supply, so as to achieve the purpose of energy saving operation. In this study, numerical modelling was used to simulate the control scheme of the heat and humidity environment. Compared with the traditional method, the two new dehumidification schemes can take about 1/3 of the wet load of the main workshop, and the dehumidification efficiency is improved. Therefore, this study is expected to be a promising tool for reducing air humidity in underground workshops.

Dry-wet spinning process was used to gain graphene oxide/polyimide composite fibers, then graphene/polyimide composite carbon and graphite fibers were obtained through carbonized and graphitized. Different graphene oxide contents of the composite carbon and graphite fibers were measured by thermal gravimetric analysis, Raman, mechanical properties, electrical properties,SEM and so on. The results show that when the GO content is 0.3%(mass fraction,the same below), the thermal property of the graphene oxide/polyimide composite fibers is the best. The mechanical and electrical properties are obriously improved by the addition of GO, graphitization degree also increases. When the composite carbon fibers are treated at 2800℃, GO content increases to 2.0%, the thermal conductivity of the composite graphite fibers reaches 435.57W·m-1·K-1 and cross-section structures of carbon fibers are more compact.

The complete chloroplast genome sequence of Populus koreana was characterized using Illumina pair-end sequencing. The chloroplast genome of P. koreana was 156,868 bp in length, containing a large single-copy region (LSC) of 84,976 bp, a small single-copy region (SSC) of 16,606 bp, and two inverted repeat (IR) regions of 27,643 bp. The overall GC content is 30.70%, whereas the corresponding values of the LSC, SSC, and IR regions are 64.6%, 69.2%, and 60.1%, respectively. The genome contains 131 complete genes, including 86 protein-coding genes (62 protein-coding gene species), 37 tRNA genes (29 tRNA species), and eight rRNA genes (four rRNA species). The neighbour-joining phylogenetic analysis showed that P. koreana and Populus fremontii clustered together as sisters to other Populus species.

BACKGROUND: While it is well-established that exposure to dampness or mold in homes negatively affects physical health, the association with mental health remains less well evidenced. As plausible psychosocial and biological pathways exist between dampness and mold exposure and poor mental health, a review of evidence is required. OBJECTIVE: This State-of-the-Science review sought to assess what is known about the mental health effects of dampness or mold exposure and identify gaps in the literature and priorities for further research. METHODS: A comprehensive search of electronic databases (MEDLINE, Embase, PsycInfo, Global Health, Web of Science, and Scopus) was conducted to identify relevant studies published from 2003 to 2023. Eligible studies included observational study designs such as cohort and crosssectional studies. Target studies for review assessed the effect of dampness and/or mold on mental health outcomes. RESULTS: Of the 1,169 records retrieved, 19 studies met the inclusion criteria. The available evidence described positive associations between residential dampness/mold exposure and poor mental health. In adults, associations were observed for outcomes such as depression, stress, and anxiety, while for children, associations were observed for emotional symptoms and emotional dysregulation. DISCUSSION: Identified studies generally reported associations between exposure to dampness/mold in the home and poorer mental and emotional health. Given the methodological limitations present in the current evidence base, it is recommended that more research be conducted. https://doi.org/10.1289/EHP14341, Introduction The World Health Organization (WHO) guidelines on indoor air quality emphasize that mold exposure poses a significant risk to human health. (1) The prevalence of mold growth in dwellings [...]

Based on the characteristics of raise boring technology and air drilling technology, the construction equipment and process of raise boring with air as circulating medium are studied. Raise air drilling equipment includes the hydraulic control system, the air-cooled cooler and the air compressor. The drilling process is that the bit is cooled by the high-pressure air, at the same time, the broken rock debris generated in the drilling process are discharged to the ground, and the high temperature hydraulic oil is cooled by the air-cooler cooler. By the study above, the problems are solved effectively such as heat dissipation, cooling and rock debris collection and discharge in the process of construction with raise boring machines without drilling fluids. Based on the basic assumption and the aerodynamic theory, the circulation system pressure of the raise air drilling is studied, the calculation method and formula of the annular pressure drop, bit pressure drop and rod pressure drop are presented. The research results can provide theoretical guidance and technical support for the application of raise air drilling technology.