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Physical and mechanical properties and microstructures of submarine soils in the Yellow Sea

Deep Underground Science and Engineering 2024年第2期3卷 197-206页

作者： Zhuangcai Tian Yihua Chang Sichao Chen Gengchen Wang Yanhong Hu Chuan Guo lei jia lei Song jianhua Yue State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhouChina School of Mechanics and Civil Engineering China University of Mining and TechnologyXuzhouChina Research Center for Deep Ocean Science and Underwater Engineering China University of Mining and TechnologyXuzhouChina School of Resources and Geosciences China University of Mining and TechnologyXuzhouChina

In recent years,the exploration of seabed has been intensified,but the submarine soils of silt and sand in the Yellow Sea area have not been well investigated so far.In this study,the physical and mechanical properties of silt and sand from the Yellow Sea were measured using a direct shear apparatus and their microstructures were observed using a scanning electron microscope.The test results suggest that the shear strength of silt and sand increases linearly with the increase of normal stress.Based on the direct shear test,the scanning electron microscope was used to observe the section surface of sand.It is observed that the section surface becomes rough,with many“V”‐shaped cracks.Many particles appear on the surface of the silt structure and tend to be disintegrated.The X‐ray diffraction experiment reveals that the sand and silt have different compositions.The shear strength of sand is slightly greater than that of silt under high stress,which is related to the shape of soil particles and the mineral composition.These results can be a reference for further study of other soils in the Yellow Sea;meanwhile,they can serve as soil parameters for the stability and durability analyses of offshore infrastructure construction.

关键词： direct shear test microscope physical properties submarine soil Yellow Sea

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Pleural empyema with endobronchial mass due to Rhodococcus equi infection after renal transplantation: A case report and review of literature

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World Journal of Clinical Cases 2024年第1期12卷 224-231页

作者： Guo-Fu Liang Sheng Chao Zhou Sun Ke-Jing Zhu Qian Chen lei jia Yu-Lin Niu Department of Organ Transplantation School of Clinical MedicineGuizhou Medical UniversityGuiyang 550025Guizhou ProvinceChina Department of Organ Transplantation The Affiliated Hospital of Guizhou Medical UniversityGuiyang 550000Guizhou ProvinceChina

BACKGROUND Kidney transplantation is the best option for patients with end-stage renal disease.However,the need for lifelong immunosuppression results in renal transplant recipients being susceptible to various infections.Rhodococcus equi(R.equi)is a rare opportunistic pathogen in humans,and there are limited reports of infection with R.equi in post-renal transplant recipients and no uniform standard of treat-ment.This article reports on the diagnosis and treatment of a renal transplant recipient infected with R.equi 21 mo postoperatively and summarizes the charac-teristics of infection with R.equi after renal transplantation,along with a detailed review of the literature.Here,we present the case of a 25-year-old man who was infected with R.equi 21 mo after renal transplantation.Although the clinical features at the time of presentation were not specific,chest computed tomography(CT)showed a large volume of pus in the right thoracic cavity and right middle lung atelectasis,and fiberoptic bronchoscopy showed an endobronchial mass in the right middle and lower lobe orifices.Bacterial culture and metagenomic next-generation sequen-cing sequencing of the pus were suggestive of R.equi infection.The immunosup-pressive drugs were immediately suspended and intravenous vancomycin and azithromycin were administered,along with adequate drainage of the abscess.The endobronchial mass was then resected.After the patient’s clinical symptoms and chest CT presentation resolved,he was switched to intravenous ciprofloxacin and azithromycin,followed by oral ciprofloxacin and azithromycin.The patient was re-hospitalized 2 wk after discharge for recurrence of R.equi infection.He recovered after another round of adequate abscess drainage and intravenous ciprofloxacin and azithromycin.CONCLUSION Infection with R.equi in renal transplant recipients is rare and complex,and the clinical presentation lacks specificity.Elaborate antibiotic therapy is required,and adequate abscess drainage and surgical excision are necessary.Given the recurre

关键词： Kidney transplantation Rhodococcus equi Pleural empyema Pulmonary atelectasis Immunosuppression Case report

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Evolution of microstructure and properties of a novel Ni-based superalloy during stress relief annealing

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International Journal of Minerals,Metallurgy and Materials 2024年第8期 1876-1889页

作者： lei jia Heng Cui Shufeng Yang Shaomin Lü Xingfei Xie Jinglong Qu Collaborative Innovation Center of Steel Technology University of Science and Technology Beijing State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Beijing GAONA Materials & Technology Co. Ltd. High-Temperature Materials Institute Central Iron and Steel Research Institute

We discussed the decrease in residual stress, precipitation evolution, and mechanical properties of GH4151 alloy in different annealing temperatures, which were studied by the scanning electron microscope（SEM）, high-resolution transmission electron microscopy（HRTEM）, and electron backscatter diffraction（EBSD）. The findings reveal that annealing processing has a significant impact on diminishing residual stresses. As the annealing temperature rose from 950 to 1150°C, the majority of the residual stresses were relieved from 60.1 MPa down to 10.9 MPa. Moreover, the stress relaxation mechanism transitioned from being mainly controlled by dislocation slip to a combination of dislocation slip and grain boundary migration. Meanwhile, the annealing treatment promotes the decomposition of the Laves, accompanied by the precipitation of μ-（Mo---6Co7） starting at 950°C and reaching a maximum value at 1050°C. The tensile strength and plasticity of the annealing alloy at 1150°C reached the maximum（1394 MPa, 56.1%） which was 131%, 200% fold than those of the as-cast alloy（1060 MPa, 26.6%）, but the oxidation process in the alloy was accelerated at 1150°C. The enhancement in durability and flexibility is primarily due to the dissolution of the brittle phase, along with the shape and dispersal of the γ′ phase.

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Case Studies of the Microphysical and Kinematic Structure of Summer Mesoscale Precipitation Clouds over the Eastern Tibetan Plateau

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Advances in Atmospheric Sciences 2024年第1期41卷 97-114页

作者： Shuo jia Jiefan YANG Hengchi lei Key Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

Three cases of microphysical characteristics and kinematic structures in the negative temperature region of summer mesoscale cloud systems over the eastern Tibetan Plateau(TP)were investigated using X-band dual-polarization radar.The time-height series of radar physical variables and mesoscale horizontal divergence δderived by quasi-vertical profiles(QVPs)indicated that the dendritic growth layer(DGL,-20°C to-10°C)was ubiquitous,with large-value zones of K_(DP)(specific differential phase),Z_(DR)(differential reflectivity),or both,and corresponded to various dynamic fields(ascent or descent).Ascents in the DGL of cloud systems with vigorous vertical development were coincident with large-value zones of Z_(DR),signifying ice crystals with a large axis ratio,but with no obvious large values of K_(DP),which differs from previous findings.It is speculated that ascent in the DGL promoted ice crystals to undergo further growth before sinking.If there was descent in the DGL,a high echo top corresponded to large values of K_(DP),denoting a large number concentration of ice crystals;but with the echo top descending,small values of K_(DP) formed.This is similar to previous results and reveals that a high echo top is conducive to the generation of ice crystals.When ice particles fall to low levels(-10℃ to 0℃),they grow through riming,aggregation,or deposition,and may not be related to the kinematic structure.It is important to note that this study was only based on a limited number of cases and that further research is therefore needed.

关键词： Tibetan Plateau polarimetric variables microphysics dendritic growth layer kinematic structure aggregation riming

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Expression of cyclin-dependent kinase 9 is positively correlated with the autophagy level in colon cancer

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World Journal of Gastrointestinal Oncology 2024年第2期16卷 314-330页

作者： lei Zheng jia Lu Da-Lu Kong Department of Colorectal Cancer Surgery National Clinical Research Center for CancerKey Laboratory of Cancer Immunology and Biotherapy of TianjinTianjin Key Laboratory of Digestive CancerKey Laboratory of Cancer Prevention and Therapy of TianjinTianjin’s Clinical Research Center for CancerTianjin Medical University Cancer Institute and HospitalTianjin 300060China Department of Infection Management National Clinical Research Center for CancerKey Laboratory of Cancer Immunology and Biotherapy of TianjinTianjin Key Laboratory of Digestive CancerKey Laboratory of Cancer Prevention and Therapy of TianjinTianjin’s Clinical Research Center for CancerTianjin Medical University Cancer Institute and HospitalTianjin 300060China

BACKGROUND Cyclin-dependent kinase 9(CDK9)expression and autophagy in colorectal cancer(CRC)tissues has not been widely studied.CDK9,a key regulator of transcription,may influence the occurrence and progression of CRC.The expression of auto-phagy-related genes BECN1 and drug resistance factor ABCG2 may also play a role in CRC.Under normal physiological conditions,autophagy can inhibit tumorigenesis,but once a tumor forms,autophagy may promote tumor growth.Therefore,understanding the relationship between autophagy and cancer,partic-ularly how autophagy promotes tumor growth after its formation,is a key motivation for this research.AIM To investigate the relationship between CDK9 expression and autophagy in CRC,assess differences in autophagy between left and right colon cancer,and analyze the associations of autophagy-related genes with clinical features and prognosis.METHODS We collected tumor tissues and paracarcinoma tissues from colon cancer patients with liver metastasis to observe the level of autophagy in tissues with high levels of CDK9 and low levels of CDK9.We also collected primary tissue from left and right colon cancer patients with liver metastasis to compare the autophagy levels and the expression of BECN1 and ABCG2 in the tumor and paracarcinoma tissues.RESULTS The incidence of autophagy and the expression of BECN1 and ABCG2 were different in left and right colon cancer,and autophagy might be involved in the occurrence of chemotherapy resistance.Further analysis of the rela-tionship between the expression of autophagy-related genes CDK9,ABCG2,and BECN1 and the clinical features and prognosis of colorectal cancer showed that the high expression of CDK9 indicated a poor prognosis in colorectal cancer.CONCLUSION This study laid the foundation for further research on the combination of CDK9 inhibitors and autophagy inhibitors in the treatment of patients with CRC.

关键词： Autophagy Tumorigenesis Tumor tissue Paracarcinoma tissue Expression Left/right colon cancer

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Remediation of di(2-ethylhexyl)phthalate(DEHP)contaminated black soil by freeze-thaw aging biochar

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Journal of Environmental Sciences 2024年第1期135卷 681-692页

作者： lei Wang Zeyu Dou Chaoran Ma Xiaochen jia Hongye Wang Wenjing Bao lei Wang jianhua Qu Ying Zhang School of Resources and Environment Northeast Agricultural UniversityHarbin 150030China

Di(2-ethylhexyl)phthalate(DEHP),a complex structure with high toxicity,is a common organic pollutant.This study investigated the effects of fresh biochar(FBC),and freeze-thaw cycled aged biochar(FTC-BC)on DEHP-contaminated soils using a pot experiment.The specific surface area of FBC increased from 145.20 to 303.50 m~2/g,and oxygen-containing functional groups increased from 1.26 to 1.48 mol/g after freeze-thaw cycles,greatly enhancing the adsorption of DEHP by biochar in the soil.The comprehensive radar chart evaluation showed that FBC and FTC-BC reduced DEHP growth stress and improved the soil properties.Compared with FBC,FTC-BC performed better in protecting the normal growth of pakchoi and improving soil properties.In addition,the application of biochar increased the diversity and abundance of bacteria in the DEHP-contaminated soil and changed the composition of the soil bacterial community.The partial least squares path model(PLS-PM)showed that adding biochar as a soil remediation agent significantly positively impacted soil nutrients and indirectly reduced the DEHP levels in soil and plants by increasing soil microbial diversity.Compared with FBC,FTC-BC creates a more satisfactory living environment for microorganisms and has a better effect on the degradation of DEHP in the soil.This study provides a theoretical basis for future biochar remediation of DEHP-contaminated soils in cold high-latitude regions.

关键词： DEHP Freeze-thaw cycles Biochar Soil restoration

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Quartz-enhanced multiheterodyne resonant photoacoustic spectroscopy

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Light(Science & Applications) 2024年第4期13卷 696-705页

作者： jiapeng Wang Hongpeng Wu Angelo Sampaolo Pietro Patimisco Vincenzo Spagnolo Suotang jia lei Dong State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Laser SpectroscopyShanxi UniversityTaiyuan 030006China. Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China. PolySense Lab Dipartimento Interateneo di FisicaUniversity and Politecnico of BariCNR-IFNVia Amendola 17370126 BariItaly

The extension of dual-comb spectroscopy(DCS)to all wavelengths of light along with its ability to provide ultralarge dynamic range and ultra-high spectral resolution,renders it extremely useful for a diverse array of applications in physics,chemistry,atmospheric science,space science,as well as medical applications.In this work,we report on an innovative technique of quartz-enhanced multiheterodyne resonant photoacoustic spectroscopy(QEMR-PAS),in which the beat frequency response from a dual comb is frequency down-converted into the audio frequency domain.In this way,gas molecules act as an optical-acoustic converter through the photoacoustic effect,generating heterodyne sound waves.Unlike conventional DCS,where the light wave is detected by a wavelengthdependent photoreceiver,QEMR-PAS employs a quartz tuning fork(QTF)as a high-Q sound transducer and works in conjunction with a phase-sensitive detector to extract the resonant sound component from the multiple heterodyne acoustic tones,resulting in a straightforward and low-cost hardware configuration.This novel QEMRPAS technique enables wavelength-independent DCS detection for gas sensing,providing an unprecedented dynamic range of 63 dB,a remarkable spectral resolution of 43 MHz(or~0.3 pm),and a prominent noise equivalent absorption of 5.99×10^(-6)cm^(-1)·Hz-1/2.

关键词： Quartz hardware resonant

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Recent applications of macrocycles in supramolecular catalysis

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Chinese Chemical Letters 2024年第4期35卷 132-141页

作者： Conghui Wang lei Xu Zhenhua jia Teck-Peng Loh College of Advanced Interdisciplinary Science and Technology Henan University of TechnologyZhengzhou 450001China Division of Chemistry and Biological Chemistry School of Chemistry Chemical Engineeringand BiotechnologyNanyang Technological UniversitySingapore 637371Singapore Institute of Advanced Synthesis School of Chemistry and Molecular Engineering Nanjing Tech UniversityNanjing 211816China

Numerous supramolecular macrocycles have been utilized for developing catalysts by exploiting their specific molecular recognition and ability to form inclusion complexes through noncovalent interactions. The cyclic structure and modified functional groups of these macrocycles can influence substrate and transition state stability, as well as reaction selectivity. The inner cavities of these macrocycles are particularly beneficial, as they enable substrates to adopt preorganized arrangements and serve as versatile platforms for highly efficient supramolecular catalytic systems. This minireview provides an overview of recent advancements in supramolecular catalysis using various macrocycles, such as crown ethers, cyclodextrins,calixarenes, pillararenes, cucurbiturils, and other novel macrocycles.

关键词： Supramolecular catalysis Macrocycle Host-guest interactions Confinement Selectivity

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Distributed Nash Equilibrium Seeking Strategies Under Quantized Communication

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 103-112页

作者： Maojiao Ye Qing-Long Han lei Ding Shengyuan Xu Guobiao jia IEEE the School of Automation Nanjing University of Science and TechnologyNanjing 210094China the School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyMelbourne VIC 3122Australia the Institute of Advanced Technology Nanjing University of Posts and TelecommunicationsNanjing 210023China

This paper is concerned with distributed Nash equi librium seeking strategies under quantized communication. In the proposed seeking strategy, a projection operator is synthesized with a gradient search method to achieve the optimization o players' objective functions while restricting their actions within required non-empty, convex and compact domains. In addition, a leader-following consensus protocol, in which quantized informa tion flows are utilized, is employed for information sharing among players. More specifically, logarithmic quantizers and uniform quantizers are investigated under both undirected and connected communication graphs and strongly connected digraphs, respec tively. Through Lyapunov stability analysis, it is shown that play ers' actions can be steered to a neighborhood of the Nash equilib rium with logarithmic and uniform quantizers, and the quanti fied convergence error depends on the parameter of the quan tizer for both undirected and directed cases. A numerical exam ple is given to verify the theoretical results.

关键词： Consensus distributed Nash equilibrium seeking projected gradient play quantized communication

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An approximate analytical model for unconventional reservoir considering variable matrix blocks and simultaneous matrix depletion

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Petroleum Science 2024年第1期21卷 352-365页

作者： Kai-Xuan Qiu jia Li Dong Feng Shi-Ming Wei Gang lei jiangmen Laboratory of Carbon Science and Technology Jiangmen529100GuangdongChina The Hong Kong University of Science and Technology(Guangzhou) Guangzhou511400GuangdongChina China University of Geosciences(Beijing) Beijing100083China China University of Petroleum(Beijing) Beijing102249China China University of Geosciences(Wuhan) Wuhan430074HubeiChina Shenzhen Research Institute China University of GeosciencesShenzhen518063GuangdongChina

In regard to unconventional oil reservoirs,the transient dual-porosity and triple-porosity models have been adopted to describe the fluid flow in the complex fracture network.It has been proven to cause inaccurate production evaluations because of the absence of matrix-macrofracture communication.In addition,most of the existing models are solved analytically based on Laplace transform and numerical inversion.Hence,an approximate analytical solution is derived directly in real-time space considering variable matrix blocks and simultaneous matrix depletion.To simplify the derivation,the simultaneous matrix depletion is divided into two parts:one part feeding the macrofractures and the other part feeding the microfractures.Then,a series of partial differential equations(PDEs)describing the transient flow and boundary conditions are constructed and solved analytically by integration.Finally,a relationship between oil rate and production time in real-time space is obtained.The new model is verified against classical analytical models.When the microfracture system and matrix-macrofracture communication is neglected,the result of the new model agrees with those obtained with the dual-porosity and triple-porosity model,respectively.Certainly,the new model also has an excellent agreement with the numerical model.The model is then applied to two actual tight oil wells completed in western Canada sedimentary basin.After identifying the flow regime,the solution suitably matches the field production data,and the model parameters are determined.Through these output parameters,we can accurately forecast the production and even estimate the petrophysical properties.

关键词： Analytical solution Unconventional reservoir Variable matrix Simultaneous flow

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