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Yufeng Ling,1 Menglu Duan,1 Wen Lyu,1 Jie Yang,1,2 Yu Liu,1,3 Shuangshuang Ren,1,4 Wenlei Wu1,3 1Central Laboratory of Stomatology, Nanjing Stomatological Hospital, Affiliated Hospital of Medical School, Research Institute of Stomatology, Nanjing University, Nanjing, People’s Republic of China; 2Department of Periodontology, Nanjing Stomatological Hospital, Affiliated Hospital of Medical School, Research Institute of Stomatology, Nanjing University, Nanjing, People’s Republic of China; 3Department of Senior Specialist, Nanjing Stomatological Hospital, Affiliated Hospital of Medical School, Research Institute of Stomatology, Nanjing University, Nanjing, People’s Republic of China; 4Department of Cariology and Endodontics, Nanjing Stomatological Hospital, Affiliated Hospital of Medical School, Research Institute of Stomatology, Nanjing University, Nanjing, People’s Republic of ChinaCorrespondence: Wenlei Wu; Shuangshuang Ren, Tel +025-83620252 ; +025-83620215, Email wlwu@nju.edu.cn; zjndrenss@163.comIntroduction: Periodontitis, a chronic inflammatory disease prevalent worldwide, is primarily treated through GTR for tissue regeneration. The efficacy of GTR, however, remains uncertain due to potential infections and the intricate microenvironment of periodontal tissue. Herein, We developed a novel core-shell structure multifunctional membrane using a dual-drug-loaded coaxial electrospinning technique (Lys/ACP-CNF), contains L-lysine in the outer layer to aid in controlling biofilms after GTR regenerative surgery, and ACP in the inner layer to enhance osteogenic performance for accelerating alveolar bone repair.Methods: The biocompatibility and cell adhesion were evaluated through CCK-8 and fluorescence imaging, respectively. The antibacterial activity was assessed using a plate counting assay. ALP, ARS, and RT-qPCR were used to examine osteogenic differentiation. Additionally, an in vivo experiment was conducted on a rat model with acute periodontal defect and infection. Micro-CT and histological analysis were utilized to analyze the in vivo alveolar bone regeneration.Results: Structural and physicochemical characterization confirmed the successful construction of the core-shell fibrous structure. Additionally, the Lys/ACP-CNF showed strong antibacterial coaggregation effects and induced osteogenic differentiation of PDLSCs in vitro. The in vivo experiment confirmed that Lys/ACP-CNF promotes new bone formation.Conclusion: Lys/ACP-CNF rapidly exhibited excellent antibacterial activity, protected PDLSCs from infection, and was conducive to osteogenesis, demonstrating its potential application for clinical periodontal GTR surgery. Keywords: anti-microbial therapy, L-lysine, electrospun membrane, osteogenic, periodontal tissue regeneration

Yingyi Zhu,1,&ast; Kangyao Cheng,1,&ast; Hui Wang,1 Ziwei Xu,1 Ruiyu Zhang,1 Wenjie Cheng,1 Yan Wang,2 Weibo Lyu1 1School of Nursing, Shanghai University of Traditional Chinese Medicine, Shanghai, People’s Republic of China; 2Nursing Department, Tangzhen Community Healthcare Center, Shanghai, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Yan Wang, Tangzhen Community Healthcare Center, 75 Middle Chuangxin Road, Shanghai, 201203, People’s Republic of China, Tel +86 13816514677, Email guwangxin@aliyun.com Weibo Lyu, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai, 201210, People’s Republic of China, Tel +86 13661498053, Email Lyu_weibo@shutcm.edu.cnPurpose: To explore exercise adherence and compliance as well as its related factors among elderly patients with type 2 diabetes mellitus (T2DM) to provide a basis for clinical intervention strategies.Patients and Methods: The present study was a cross-sectional study of 205 elderly patients with T2DM who regularly visited a Shanghai community health center from August 2020 to July 2021. Exercise adherence and compliance was measured using an exercise adherence and compliance questionnaire, and potential correlates were explored using multiple linear regression analysis.Results: The mean total score of the exercise adherence and compliance questionnaire was 16.72± 5.08. The stepwise regression results revealed that exercise adherence and compliance was positively correlated with self-monitoring (F=3.510, P=0.005), exercise knowledge (r=0.784, P< 0.001), exercise willingness (r=0.556, P< 0.001), professional support (r=0.426, P< 0.001), and self-efficiency (r=0.5, P< 0.001). There was a negative correlation between hypoglycemia and exercise adherence and compliance (F=− 3.672, P< 0.001).Conclusion: Low exercise adherence and compliance was related to low glucose self-monitoring frequency, increased hypoglycemia, less exercise knowledge, less exercise willingness, less professional support, and less self-efficiency. When developing exercise instructions adapted to the cognitive and volitional needs of diabetic patients, it is essential to focus on their daily self-management habits and extrinsic motivation to improve exercise adherence and compliance.Keywords: aged, type 2 diabetes mellitus, T2DM, exercise, adherence and compliance

Hui Li,1 Lu Xie,1 Hongdi Yao,2 Lexing Zhang,3 Sanhong Liang,1 Wen Lyu1 1Department of Gastroenterology, Hangzhou First People’s Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, People’s Republic of China; 2Zhejiang Chinese Medical University School, Hangzhou, Zhejiang, People’s Republic of China; 3Department of Radiology, Hangzhou First People’s Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, People’s Republic of ChinaCorrespondence: Wen Lyu, Department of Gastroenterology, Hangzhou First People’s Hospital, Zhejiang University School of Medicine, 4 Xueshi Road, Shangcheng District, Hangzhou, 310000, Zhejiang, People’s Republic of China, Email lihui-cy@163.comBackground: The incidences of enterovesical and enterocutaneous fistulas are extremely low, and enterovesical and enterocutaneous fistulas are difficult to treat in patients with Crohn’s disease.Case Summary: In this case, the patient had recurrent abdominal pain and diarrhea for more than 2 years, with fecal residue in the urine for 6 days. Pelvic magnetic resonance imaging and colonoscopy showed intestinal infection with a rectal fistula, and the initial diagnosis was severely active Crohn’s disease with an enterovesical fistula. The patient had multiple internal fistulas and infections, and strongly refused surgical conditions. The patient was given an intravenous infusion of ustekinumab and somatostatin, with anti-infective treatment, nutritional support and regulation of the intestinal flora. Drainage and debridement of the cutaneous fistula were performed. After comprehensive treatment and management, the patient’s condition achieved significant clinical remission.Conclusion: This patient achieved clinical response and will receive follow-up for another dose of ustekinumab after 12 weeks. The patient developed enterovesical and enterocutaneous fistulas, the incidence of multiple fistulas which are low in patients with CD and are difficult to cure and prone to relapse. Only few patients achieve complete remission. At present, there is no standard and effective treatment for CD with multiple fistulas. Usually, surgery is performed for treatment. Drug therapy, especially with biological agents, should be selected as the first-line pre-operative treatment. Clinicians, especially gastroenterologists, need to improve their knowledge of these conditions and update the treatment consensus guidelines in a timely manner. Clinicians need to take into account the patient’s condition and willingness when developing an effective treatment plan.Keywords: Crohn’s disease, enterovesical fistula, enterocutaneous fistula, ustekinumab, therapy

In order to improve the orderly control and flexible adjustment capabilities of large-scale distributed power sources connected to the distribution network, it is currently an effective method to reasonably divide the distributed power sources into clusters and use the cluster as the basic unit for regulation. To this end, a distributed power cluster partitioning method that considers the adjustable capacity and response speed of flexible resources is proposed. Firstly, the modularity index and the active power balance index are proposed to characterize the structural and power balance capability of clusters. Secondly, based on the analysis of the cluster's flexible response capability, and in view of the problem that it is difficult to quantify the impact of the flexible resource response capacity and response speed on the adjustment capability, it is proposed to take the cumulative area of deviation between the response curve of cluster output and the net load curve as the indicator of the flexible response capability of clusters, and the influence of the allocation of energy storage capacity on the delineation of clusters is also taken into account. Then, a cluster division objective function that comprehensively considers the modularity index, active power balance index, cluster flexible response capability index and energy storage unit allocation index is proposed, and this function is solved using an improved adaptive genetic algorithm. Finally, the proposed method is verified in the improved IEEE 33-node system and IEEE 69-node system. The results show that the cluster partitioning method based on the proposed comprehensive performance index can improve the cluster flexible response capability by more than 20% on the basis of ensuring the structural strength of the cluster, which verifies the effectiveness and superiority of the cluster partitioning method proposed in this paper.

AIM: To assess the association between the Dem, axial length/corneal radius ratio(AL/CR ratio), and the refractive status of children aged 3 to 14, compare the efficiency of Dem with AL/CR ratio in predicting myopia, and to explore a more effective method for quantitatively predicting the refractive state of children.METHODS: This cross-sectional study involved 519 children aged 3 to 14, including 519 eyes(data from the right eyes were used). All participants were out-patients at the ophthalmic clinic of Xi'an No.1 Hospital from March 2021 to December 2022. The axial length(AL), keratometry(K), Dem, and spherical equivalent refraction(SER)were recorded before ciliary paralysis, and myopia was defined when the SER ≤-0.50 D.RESULTS: There was a positive correlation between SER and Dem(r=0.88, P

High-velocity air-fuel spray （HVAF） technology was used to prepare two kinds of Al-based amorphous alloy coatings with high porosity （HP） of 1.36% and low porosity （LP） of 0.86%. The effects of porosities on the corrosion behavior of Al-based amorphous alloy coatings were studied. The porosities and microstructures of the coatings were analyzed by scanning electron microscope （SEM） and X-ray diffraction （XRD） combined with three-dimensional X-ray tomography （3D XRT）. The corrosion properties of the coatings were studied by electrochemical testing system and contact angle measuring instrument. The passive film components of the two coatings were analyzed by X-ray photoelectron spectroscopy （XPS）. The results show that the self-corrosion current density （Icorr） and pitting potential （Epit） of the LP coatings are 3.0×10-6 A/cm2 and -0.40 V， respectively. The Icorr and Epit for HP coatings are 6.0×10－6 A/cm2 and -0.47 V， respectively， signifying that the LP coating has better resistance to the localized corrosion； the charge transfer resistance （Rct） of LP coatings is about twice than that of HP coating； the LP coating has a larger contact angle， which proves that LP coating has better hydrophobicity and stronger corrosion resistance； the contents of RE2O3 in the passive film formed on the LP coating are larger， which further indicates that LP coating has better corrosion resistance.

At present, the decision-making of coal mine roof disaster prevention and control measures and the analysis of accident causes mainly rely on manual experience, and the level of intelligence is relatively low. The knowledge graph of roof disaster prevention and control can integrate knowledge and experience of roof disaster prevention and control, assist in analyzing the causes of roof disaster accidents and making decisions on roof disaster prevention and control measures. A method for constructing a knowledge graph of coal mine roof disaster prevention and control has been proposed. The ontology method is used to complete the knowledge modeling of coal mine roof disaster prevention and control. The concepts in the field of roof disaster prevention and control are divided into mine geology, mining technology, prevention and control measures, and accident characterization. The relationships between concepts are defined as usage, triggering, susceptibility, control, prevention, and applicability. The knowledge modeling lays the foundation for the knowledge extraction of coal mine roof disaster prevention and control (entity extraction and relationship extraction). Based on the characteristics of entity overlapping between a large number of nested entities and relationships in the field of coal mine roof disaster prevention and control, a span based entity extraction method and a dependency syntax tree guided entity representation based relationship extraction method are determined. The method constructs a corpus in the field of roof disaster prevention and control, and uses the Neo4j graph database to store data, providing data source support for the application of knowledge graph of roof disaster prevention and control. The partial construction results of the knowledge graph of coal mine roof disaster prevention and control are displayed. It indicates that this knowledge graph can assist in the analysis of roof disaster accident causes and decision-making of prevention and control measures, thereby improving the intelligence level of roof management. It is pointed out that based on this knowledge graph, combined with natural language processing and knowledge reasoning technologies, knowledge Q&A on roof management can be achieved.

Zr-Y modified silicide coating was deposited on TC4 alloy by the pack cementation process. The microstructure， friction and wear performance， and wear mechanisms of the coating were investigated. The results show that the Zr-Y modified silicide coating has a multi-layer structure， an outer layer consists of TiSi2 and a small amount of ZrSi2， a thin middle layer is TiSi， and an inner layer is a mixture of Ti5Si4 and Ti5Si3. The micro-hardness of the coating is much higher than that of the TC4 substrate and exhibits an obvious decrease tendency from the surface to the interior. The Zr-Y modified silicide coating possesses good anti-wear performance when wearing against GCr15 and Al2O3 balls at a high-temperature of 600 ℃. When wearing against GCr15， the wear rate of the coating is about 3.59×10-5 mm3/（N·m）， which is about 36.6% of that of the TC4 substrate， and the main wear mechanisms are characterized by the adhesive of GCr15 on the coating surface and oxidation wear. When wearing against the Al2O3 ball， the wear rate of the coating is about 9.75×10-5 mm3/（N·m）， which is about 18.9% of that of the TC4 substrate， and the wear mechanisms are fatigue wear， oxidation wear， and adhesion wear.

TiB was planted into the matrix titanium alloy through the rapid solidification process, and the new ultrafine network reinforced titanium matrix composites (TMCs) powder was formed. Based on the laser additive manufacturing technology, a new titanium matrix composite with alternate distribution of equiaxed network and columnar network structure were creatively fabricated, the formation mechanism of the network structure was systematically discussed, and the mechanical properties of the super-solidified TMCs by additive manufacturing were tested. The results indicate that the network structure (about 9 μm) of the additively manufactured TiB/Ti composites is mainly composed of in-situ nano-TiB whiskers, presenting two crystal structures of B27 and Bf. The direct introduction of B element is easy to form constitutional supercooling at the solidification interface. The equiaxed α phases are obtained by promoting the alternating formation of equiaxed/columnar network structure and refining the grain size. In addition, the formed nano-TiB network structure, not only inhibits the crack deflection and passivate cracks, but also confines the large number of slip lines inside the TiB network structure via in-situ observation, inducing high-density dislocations at the grain boundaries, which limites its plastic deformation, and greatly improves the strength of the composites. The additively manufactured TiB/Ti composites increases the tensile strength by 42%, and maintains the elongation of about 10%.

Fanconi anemia (FA) is an inheritable disorder that presents with bone marrow failure, developmental anomalies, and an increased susceptibility to cancer. The etiology of this condition stems from a genetic mutation that disrupts the proper repair of interstrand DNA cross-links (ICLs). The resultant dysregulation of the DNA damage response mechanism can induce genomic instability, thereby elevating the mutation rates and the likelihood of developing cancer. The FA pathway assumes a pivotal role in safeguarding genome stability through its involvement in the repair of DNA cross-links and the maintenance of overall genomic integrity. A mutation in the germ line of any of the genes responsible for encoding the FA protein results in the development of FA. The prevalence of aberrant FA gene expression in somatic cancer, coupled with the identification of a connection between FA pathway activation and resistance to chemotherapy, has solidified the correlation between the FA pathway and cancer. Consequently, targeted therapies that exploit FA pathway gene abnormalities are being progressively developed and implemented. This review critically examines the involvement of the FA protein in the repair of ICLs, the regulation of the FA signaling network, and its implications in cancer pathogenesis and prognosis. Additionally, it explores the potential utility of small-molecule inhibitors that target the FA pathway.

In recent years， there have been several serious incidents involving explosions and fires in on-load tap changers （OLTCs） of converter transformers during the adjustment. To address this issue， a novel design solution for a split type OLTC is proposed， separating the switching part from the transformer body to effectively prevent the faults in the tap changer being intensified. The vacuum permanent magnet switch replaces each contact of the switch， and the operating mechanism is independently configured. Based on current sampling devices arranged in the internal circuit， monitoring and control of the switching process are achieved. Split type synchronous control logic and step control logic for the diverter switch are introduced to monitor the status and provide fault protection during the tap changer adjustment process. Experimental results from the prototype validate the feasibility and effectiveness of the proposed OLTC design for converter transformers.

The Chinese economy has undergone high-speed, high-quality growth, and the concept of low-carbon technology has gained popular support. Businesses and consumers must jointly endeavor to achieve low-carbon economic development. Moreover, it is important to investigate whether enterprises' low-carbon behavior is correlated with consumers' green consumption behavior. We built a theoretical model to depict the relationship between corporate public welfare low-carbon behavior, consumers' green purchase intention, and green purchase behavior. We then divided corporate public welfare low-carbon behavior into three dimensions. We proposed hypotheses, collected data through a questionnaire survey, and analyzed the data using statistical analysis software of SPSS 26.0 and AMOS 24.0. Public welfare low-carbon behavior was significantly correlated with consumers’ green purchase intention, and public welfare low-carbon participation and public welfare low-carbon motivation were significantly correlated with green purchase intention. Finally, we proposed suggestions from three perspectives: the public welfare low-carbon mechanism, public welfare low-carbon participation, and public welfare low-carbon motivation. The results provide theoretical support for research methods related to the low-carbon growth of enterprises and green consumption, as well as guidance and decision-making support for enterprises in carrying out cause marketing.

As a member of the nuclear receptor subfamily, NR4A1 works with glycerol kinase, a key glucose and lipid metabolism enzyme, to lower blood glucose and boost blood lipids and maintain glucose and lipid homeostasis, while NR4A1 deficiency leads to disruption of hepatic glucose and lipid metabolism. NR4A1 is involved in maintaining the dynamic balance of oxide and antioxidants, reducing inflammatory responses, and promoting autophagy, among other activities. Since NR4A1 is closely related to the occurrence of diabetic nephropathy and other diseases,it has aroused widespread concern in recent years.

A middle-aged man was presented with poor appetite, polyuria, polydrpsia, and headache. A sellar mass was found, along with total pituitary hypofunction and visual field defect. A biopsy of the lesion via the trans-sphenoidal approach showed inflammatory changes and granuloma formation. However, repeated cerebrospinal fluid and pathogenic examination of the pathological tissue showed no positive indications. The initial diagnosis considered autoimmune hypophysitis, and treatment of glucocorticoids combined with immunosuppressants was administered, which led to a temporary shrinkage of the lesion, but it gradually enlarged subsequently. After multidisciplinary discussion, a high possibility of pituitary tuberculosis infection was decided upon. After standardized anti-tuberculosis treatment was initiated, the lesion reduced noticeably and the patient′s condition improved. Pituitary tuberculosis infection is incredibly rare and extremely easy to misdiagnose. This case was diagnosed and treated in a timely and effective manner through a multidisciplinary approach, highlighting the importance of such an approach in dealing with rare diseases.

This study reviews the metal corrosion problem regarding the carbon capture, utilization, and storage (CCUS) technology and aims to deepen the understanding and research on this problem and thus deal with the severe material corrosion failures in the capture, transportation, utilization, and storage systems. Based on the novel corrosion environments, the uniqueness of corrosion behaviors, limited cognition, and relative lack of protective measures in CCUS technology systems, this study analyzes the possible types of metal corrosion and its major influencing factors, explores the challenges it brings, and draws the following conclusions. For the CO2 organic amine capture system, the degradation mechanism of absorbents and the impact of degradation products on the corrosion process are complex, and some degradation products have a inhibitory effect on metal corrosion. The internal corrosion issue of dense-phase CO2 transmission pipelines cannot be ignored, and controlling the moisture content is the key to controlling this corrosion problem. The risk of corrosion failures leading to CO2 leakage is high in the wellbore tubing of CO2 enhanced oil recovery utilization and storage systems under the long-term coupled effects of ultra-high CO2 partial pressure, carbon source impurities, high mineralized formation water, microorganisms, and stress. Finally, the research that needs to be conducted urgently in the future is prospected, including the corrosion impact of different carbon source impurities on each subsystem, the material degradation law in the wellbore area under long-term storage conditions, and corrosion protection technologies of CCUS systems.

Under the high-energy particle impingement and cascade effect, different types of radiation damage defects occur in metals. The aggregation and evolution of radiation damage defects can lead to the destruction of the internal structural stability and the deterioration of their properties of metals. Titanium alloy is a promising radiation resistant alloy due to its advantages of light weight, high strength, high temperature resistance and low radiation activity. Aiming at the improvement of the radiation damage resistance, this work summarizes the research progress on the radiation damage defects, the microstructural features and mechanical properties of titanium alloys. In addition, the formation and evolution of radiation damage defects and the influence mechanism of radiation dose, temperature and element species on defect migration and aggregation are analyzed. The microstructure evolution of titanium alloys induced by irradiation and the radiation damage effects such as radiation hardening, radiation embrittlement and radiation creep are discussed. The radiation damage resistance properties of titanium alloys are summarized and evaluated. The existing researches are lack effective methods to inhibit the radiation damage. Finally, the effective strategies to improve the radiation resistance of titanium alloys through composition regulation and interface microstructure design are prospected.

This paper is concerned with a parabolic-elliptic chemotaxis model with density-suppressed motility and general logistic source in an n-dimensional smooth bounded domain with Neumann boundary conditions. Under the minimal conditions for the density-suppressed motility function, we explore how strong the logistic damping can warrant the global boundedness of solutions and further establish the asymptotic behavior of solutions on top of the conditions.

In order to make full use of outdoor free cooling sources to reduce building air conditioning energy consumption, accurately evaluate the potential of natural ventilation, and guide the selection and utilization of more free cooling systems, a revised degree hours method was proposed to evaluate the energy-saving potential of different free cooling methods. The conception and rationality of the method are indicated by comparing with the degree hours method. The free cooling system model was built by using TRNSYS software to analyze and verify the rationality of the calculated result of revised degree hours. The results show that the revised degree hours can take into account the heat exchange temperature difference and heat exchange efficiency, and there is a direct relationship between the revised degree hours and the system energy saving. It can compare and evaluate the application potential of different free cooling methods, guide the selection of different free cooling methods, and help the low-carbon development of refrigeration and air conditioning systems.

Objective To investigate the clinical application value of pulse indicated continuous cardiac output （PiCCO） in volume management of patients undergoing severe abdominal surgery. Methods Sixty patients undergoing severe abdominal surgery were recruited and divided into the study group （n = 30） and control group （n = 30） by random number table method. All patients received symptomatic treatment. Patients in the control group received routine monitoring to guide fluid infusion, and their counterparts in the study group were given with PiCCO monitoring to guide fluid infusion. The total volume of infusion, urine volume, duration of mechanical ventilation, mortality rate and length of hospital stay were compared between two groups. Heart rate （HR）, mean arterial pressure （MAP）, oxygenation index （OI）, central venous oxygen saturation （ScvO2）, lactic acid （LAC）, Acute Physiology and Chronic Health Evaluation II （APACHEⅡ） before treatment （T0）, after 12 h （T1） and 24 h treatment （T2） were compared between two groups. The incidence of adverse events was also compared between two groups. Results The total volume of infusion, length of hospital stay and mortality rate in the study group were significantly lower than those in the control group （all P < 0.05）. In each group, the orders of HR and OI were T0 > T1 > T2, that of MAP was T0 < T1 < T2 （all P < 0.05）. The orders of LAC level and APACHE II score were T0 > T1 > T2, and that of ScvO2 level was T0 < T1 < T2 （all P < 0.05）, respectively. In the study group, LAC level and APACHE II score at T1 and T2 were significantly lower, whereas ScvO2 at T1 and T2 was significantly higher than those in the control group （all P < 0.05）. The total incidence of adverse events in the study group was 10%, significantly lower than 33% in the control group （P < 0.05）. Conclusion PiCCO monitoring can better guide the volume management of patients undergoing severe abdominal surgery, improve clinical prognosis and yield high clinical value.

In recent years, the incidence of colorectal cancer in China has increased significantly. With the in-depth exploration of the mechanisms of colorectal cancer recurrence and metastasis, a biobank information system that can provide comprehensive biological information is becoming more and more important. This paper expounds on the construction of a multi-center colorectal cancer clinical research biobank information system that includes three subsystems as follows: a clinical electronic data acquisition system, a biological sample management system, and a biological information data platform using the micro-service architecture. This paper explains how these subsystems are used in the multi-center management module and their characteristic functions in clinical research. Data quality and interconnection are supported through standardized data management solutions such as unified coding rules, structured clinical information, standardized sample circulation information, and standardized data storage. Thereby, this system provides comprehensive biomedical information for the promotion of translational medicine research and the development of precision medicine.

The severe mining pressure of surrounding rock along goaf retaining roadway has become the bottleneck of safe and efficient production of coal mine. As one of the effective measures to effectively reduce roadway pressure, roof cutting and pressure relief has received more and more attention. Taking the wind tunnel of 91-101 working face of Wangzhuang Coal Mine as the engineering background, the variation rules of vertical displacement of surrounding rock, the distribution characteristics of stress and plastic zone along gob retaining roadway under pressure of new roof cutting are studied by combining theoretical analysis and numerical simulation, and the influence law of roof cutting height on surrounding rock deformation is revealed. The research results show that the effect of the new roof cutting technology is remarkable, the side displacement of roadway goaf is reduced by 46.7% compared with that of unbroken roof, and the optimal roof cutting height is 19 m. The average displacement of roof, floor and two sides of gob-side entry retaining is 312 mm and 128 mm respectively, and the deformation of entry retaining is effectively controlled.

In order to obtain the evaluation and calculation method of indirect evaporative free cooling potential in data center, a new method for evaluating the annual indirect evaporative free cooling potential of data center was proposed based on the division of meteorological parameters of evaporative cooling air conditioning and the calculation method of free cooling potential. Based on the hours when there is a temperature difference between the ambient temperature and the return air (return water) temperature of the data center, the judgment limit of heat exchange efficiency of indirect evaporative cooling equipment and the supply air temperature limit of the data center were added. Combined with the efficiency and air supply limit provided by the standard, a new method was adopted to count the annual operation time distribution of indirect evaporation natural system in data centers of 31 major cities in China. The results show that the potential of indirect evaporative free cooling in the data center is related to the ambient air meteorological parameters, the heat exchange efficiency of indirect evaporative cooling equipment, and the required air supply temperature limit in the data center. Air side and water side indirect evaporative free cooling air conditioning system has great applicability in China′s data center.