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Gene×environment interaction in major depressive disorder
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作者 Ming-Zhe Zhao Xu-Sheng Song Jing-Song Ma 《World Journal of Clinical Cases》 SCIE 2021年第31期9368-9375,共8页
Major depressive disorder(MDD)is a multifactorial disorder,where multiple susceptibility genes interact with environmental factors,predisposing individuals to the development of the illness.In this article,we reviewed... Major depressive disorder(MDD)is a multifactorial disorder,where multiple susceptibility genes interact with environmental factors,predisposing individuals to the development of the illness.In this article,we reviewed different gene×environment interaction(G×E)studies shifting from a candidate gene to a genome-wide approach.Among environmental factors,childhood adversities and stressful life events have been suggested to exert crucial impacts on MDD.Importantly,the diathesis-stress conceptualization of G×E has been challenged by the differential susceptibility theory.Finally,we summarized several limitations of G×E studies and suggested how future G×E studies might reveal complex interactions between genes and environments in MDD. 展开更多
关键词 Major depressive disorder gene×environment interaction Diathesis-Stress model Differential susceptibility Theory Stressful life events Childhood adversities
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Heterogeneous population distribution enhances resistance to wheat lodging by optimizing the light environment
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作者 Yibo Hu Feng Qin +6 位作者 Zhen Wu Xiaoqin Wang Xiaolong Ren Zhikuan Jia Zhenlin Wang Xiaoguang Chen Tie Cai 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第7期2211-2226,共16页
Lodging is still the key factor that limits continuous increases in wheat yields today,because the mechanical strength of culms is reduced due to low-light stress in populations under high-yield cultivation.The mechan... Lodging is still the key factor that limits continuous increases in wheat yields today,because the mechanical strength of culms is reduced due to low-light stress in populations under high-yield cultivation.The mechanical properties of the culm are mainly determined by lignin,which is affected by the light environment.However,little is known about whether the light environment can be sufficiently improved by changing the population distribution to inhibit culm lodging.Therefore,in this study,we used the wheat cultivar“Xinong 979”to establish a low-density homogeneous distribution treatment(LD),high-density homogeneous distribution treatment(HD),and high-density heterogeneous distribution treatment(HD-h)to study the regulatory effects and mechanism responsible for differences in the lodging resistance of wheat culms under different population distributions.Compared with LD,HD significantly reduced the light transmittance in the middle and basal layers of the canopy,the net photosynthetic rate in the middle and lower leaves of plants,the accumulation of lignin in the culm,and the breaking resistance of the culm,and thus the lodging index values increased significantly,with lodging rates of 67.5%in 2020–2021 and 59.3%in 2021–2022.Under HD-h,the light transmittance and other indicators in the middle and basal canopy layers were significantly higher than those under HD,and the lodging index decreased to the point that no lodging occurred.Compared with LD,the activities of phenylalanine ammonia-Lyase(PAL),4-coumarate:coenzyme A ligase(4CL),catecholO-methyltransferase(COMT),and cinnamyl-alcohol dehydrogenase(CAD)in the lignin synthesis pathway were significantly reduced in the culms under HD during the critical period for culm formation,and the relative expression levels of TaPAL,Ta4CL,TaCOMT,and TaCAD were significantly downregulated.However,the activities of lignin synthesis-related enzymes and their gene expression levels were significantly increased under HD-h compared with HD.A partial least squares path modeling analysis found significant positive effects between the canopy light environment,the photosynthetic capacity of the middle and lower leaves of plants,lignin synthesis and accumulation,and lodging resistance in the culms.Thus,under conventional high-density planting,the risk of wheat lodging was significantly higher.Accordingly,the canopy light environment can be optimized by changing the heterogeneity of the population distribution to improve the photosynthetic capacity of the middle and lower leaves of plants,promote lignin accumulation in the culm,and enhance lodging resistance in wheat.These findings provide a basis for understanding the mechanism responsible for the lower mechanical strength of the culm under high-yield wheat cultivation,and a theoretical basis and for developing technical measures to enhance lodging resistance. 展开更多
关键词 canopy light environment LIGNIN LODGING population distribution WHEAT
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Paleogene transgression process and environmental evolution in the deepwater area of the Baiyun Depression in the northern South China Sea
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作者 Peijun Qiao Yuchi Cui +2 位作者 Qiong Ma Qiang Yu Lei Shao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第4期15-24,共10页
Multiple borehole samples are collected from the Baiyun Depression in deep-water area of the northern South China Sea(SCS)in an effort to reconstruct transgression processes during the Paleogene based on palynalgal an... Multiple borehole samples are collected from the Baiyun Depression in deep-water area of the northern South China Sea(SCS)in an effort to reconstruct transgression processes during the Paleogene based on palynalgal analysis.This study indicates that the Baiyun Depression generated a large group of palynopore assemblages and fluvial/lacustrine-related algae during the early and middle Eocene when the Wenchang Formation was deposited.The entire depression was dominated by fluvial and lacustrine facies before transgression.Its eastern and southeastern sags transitioned to shallow marine environment by generating a large abundance of marine dinoflagellates during the Enping deposition of the late Eocene.Meanwhile,the southern uplift zone simply yielded fluvial/lacustrine-related palynopores and algae,and was dominated by the fluvial and lacustrine environment during the early stage of the Enping Formation,prior to shifting into transitional setting in the later period.Northwestern sags remained extensive fluvial and delta facies without existence of marine dinoflagellates.It was until the depositional stage of the Zhuhai Formation(Oligocene)that the overall depression was strongly impacted from transgression process.Both eastern and southeastern sags were mainly under deep marine setting on a continental slope while northwestern and southern areas developed transitional facies.Although distribution and accumulation patterns varied greatly among sub-sags,the overall Baiyun Depression was characterized by widespread development of marine dinoflagellates.It should be noted that the northwestern sag also partly generated large-scale river delta deposits.Due to the eustatic rise and change of SCS spreading axis,the overall Baiyun Depression was mostly influenced by the deep marine environment on a continental slope during the early Miocene.Both northwestern sag and southern uplift zone were found plentiful marine dinoflagellates.In summary,transgression initiated from the eastern and southeastern Baiyun Depression before subsequently progressing into the farther west.Evolution of transgression process is also greatly consistent with the gradual westward expansion of the SCS. 展开更多
关键词 South China Sea PALEOgene TRANSGRESSION sedimentary environment plant ecology
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Paleoenvironmental Characteristics of Paleogene Lacustrine Source Rocks in the Western Bozhong Sag,Bohai Bay Basin,China:Evidence from Biomarkers,Major and Trace Elements
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作者 WANG Xiang LIU Guangdi +6 位作者 SONG Zezhang SUN Mingliang WANG Xiaolin WANG Feilong CHEN Rongtao GENG Mingyang LI Yishu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期220-240,共21页
The organic matter(OM)enrichment mechanisms and depositional environment characteristics of lacustrine source rocks in the western Bozhong Sag,Bohai Bay Basin in Northeast China remain controversial.To address these i... The organic matter(OM)enrichment mechanisms and depositional environment characteristics of lacustrine source rocks in the western Bozhong Sag,Bohai Bay Basin in Northeast China remain controversial.To address these issues,based on Rock-Eval pyrolysis,kerogen macerals,H/C and O/C ratios,GC-MS,major and trace elements,the Dongying Formation Member(Mbr)3(E_(3)d_(3)),the Shahejie Formation mbrs 1 and 2(E_(2)s_(1+2)),and the Shahejie Mbr 3(E_(2)s_(3))source rocks in the western Bozhong Sag were studied.The above methods were used to reveal their geochemical properties,OM origins and depositional environments,all of which indicate that E_(2)s_(1+2)and E_(2)s_(3)are excellent source rocks,and that E_(3)d_(3)is of the second good quality.E_(3)d_(3)source rocks were formed under a warm and humid climate,mainly belong to fluvial/delta facies,the E_(3)d_(3)sediments formed under weakly oxidizing and freshwater conditions.Comparatively,the depositional environments of E_(2)s_(1+2)source rocks were arid and cold climate,representing saline or freshwater lacustrine facies,and the sediments of E_(2)s_(1+2)belong to anoxic or suboxic settings with large evaporation and salinity.During the period of E_(2)s_(3),the climate became warm and humid,indicating the freshwater lacustrine facies,and E_(2)s_(3)was characterized by freshwater and abundant algae.Moreover,compared with other intervals,the OM origin of E_(3)d_(3)source rocks has noticeable terrestrial input.The OM origin of the E_(2)s_(1+2)and E_(2)s_(3)are mainly plankton and bacteria.Tectonic subsidence and climate change have affected the changes of the depositional environment in the western Bozhong Sag,thus controlling the distribution of the source rocks,the geochemical characteristics in the three intervals of lacustrine source rocks have distinct differences.Overall,these factors are effective to evaluate the paleoenvironmental characteristics of source rocks by biomarkers,major and trace elements.The established models may have positive implications for research of lacustrine source rocks in offshore areas with few drillings. 展开更多
关键词 petroleum geology source rocks depositional environments biomarkers major elements trace elements Bozhong Sag
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Formation environment and hydrocarbon potential of the Paleogene Enping Formation coal measures in the ZhuⅠDepression of northern South China Sea
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作者 Yuting Yin Lei Lan +5 位作者 Dongdong Wang Ying Chen Yan Liu Youchuan Li Zengxue Li Jiamin Liu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第4期119-135,共17页
The coal-measure source rock in the Chinese sea area plays a significant role as a hydrocarbon source rock,with its genetic environment,development and distribution,and hydrocarbon generation potential serving as esse... The coal-measure source rock in the Chinese sea area plays a significant role as a hydrocarbon source rock,with its genetic environment,development and distribution,and hydrocarbon generation potential serving as essential factors for the exploration of coal-type oil and gas fields.This study focuses on the coal-measure source rock of the Paleogene Enping Formation in the ZhuⅠDepression,located in the northern South China Sea.The main geological insights obtained are as follows.The coal measures of the Enping Formation are developed in a warm and wet tropical-subtropical climate.The development environment of the coal-measure source rock in the Enping Formation includes the braided river delta upper plain peat swamp,characterized by dry forest swamp coal facies with relatively thick coal seams and a small number of layers.The braided river delta lower plain swamp-interdistributary bay of braided river delta front represents a forest edge-wetland herbaceous swamp coal facies with numerous layers of thin coal seams and poor stability.The shore swamp corresponds to an open water swamp coal facies with multiple layers of thin coal seams and poor stability.The organic matter abundance in the braided river delta upper plain is the highest,followed by the braided river delta lower plain-braided river delta front,and the shore-shallow lake.The organic matter type is predominantly typeⅡ1.Thermal evolution analysis suggests that the organic matter has progressed into a substantial oil generation stage.The hydrocarbon generation potential of the coal-measure source rock in the Enping Formation is the highest in the braided river delta upper plain,followed by the braided river delta lower plain-braided river delta front and the shore-shallow lake.Overall,this study proposes three organic facies in the coal-measure source rock of the Enping Formation:upper-plain swamp-dry forest swamp facies,lower plain-interdistributary bay-forest-herbaceous swamp facies,and lake swamp-herbaceous swamp facies. 展开更多
关键词 coal-measure source rock PALEOgene genetic environment hydrocarbon generation characteristic ZhuⅠDepression
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Influences of different alkaline and acidic diagenetic environments on diagenetic evolution and reservoir quality of alkaline lake shales
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作者 LI Changzhi GUO Pei +2 位作者 XU Jinghong ZHONG Kai WEN Huaguo 《Petroleum Exploration and Development》 SCIE 2024年第1期97-113,共17页
Thin section and argon-ion polishing scanning electron microscope observations were used to analyze the sedimentary and diagenetic environments and main diagenesis of the Permian Fengcheng Formation shales in differen... Thin section and argon-ion polishing scanning electron microscope observations were used to analyze the sedimentary and diagenetic environments and main diagenesis of the Permian Fengcheng Formation shales in different depositional zones of Mahu Sag in the Junggar Basin,and to reconstruct their differential diagenetic evolutional processes.The diagenetic environment of shales in the lake-central zone kept alkaline,which mainly underwent the early stage(Ro<0.5%)dominated by the authigenesis of Na-carbonates and K-feldspar and the late stage(Ro>0.5%)dominated by the replacement of Na-carbonates by reedmergnerite.The shales from the marginal zone underwent a transition from weak alkaline to acidic diagenetic environments,with the early stage dominated by the authigenesis of Mg-bearing clay and silica and the late stage dominated by the dissolution of feldspar and carbonate minerals.The shales from the transitional zone also underwent a transition from an early alkaline diagenetic environment,evidenced by the formation of dolomite and zeolite,to a late acidic diagenetic environment,represented by the reedmergnerite replacement and silicification of feldspar and carbonate minerals.The differences in formation of authigenic minerals during early diagenetic stage determine the fracability of shales.The differences in dissolution of minerals during late diagenetic stage control the content of free shale oil.Dolomitic shale in the transitional zone and siltstone in the marginal zone have relatively high content of free shale oil and strong fracability,and are favorable“sweet spots”for shale oil exploitation and development. 展开更多
关键词 shale diagenesis alkaline environment authigenic minerals dissolution Permian Fengcheng Formation Mahu Sag Junggar Basin
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Identification of immune cell-related prognostic genes characterized by a distinct microenvironment in hepatocellular carcinoma
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作者 Meng-Ting Li Kai-Feng Zheng Yi-Er Qiu 《World Journal of Clinical Oncology》 2024年第2期243-270,共28页
BACKGROUND The development and progression of hepatocellular carcinoma(HCC)have been reported to be associated with immune-related genes and the tumor microenvir-onment.Nevertheless,there are not enough prognostic bio... BACKGROUND The development and progression of hepatocellular carcinoma(HCC)have been reported to be associated with immune-related genes and the tumor microenvir-onment.Nevertheless,there are not enough prognostic biomarkers and models available for clinical use.Based on seven prognostic genes,this study calculated overall survival in patients with HCC using a prognostic survival model and revealed the immune status of the tumor microenvironment(TME).AIM To develop a novel immune cell-related prognostic model of HCC and depict the basic profile of the immune response in HCC.METHODS We obtained clinical information and gene expression data of HCC from The Cancer Genome Atlas(TCGA)and International Cancer Genome Consortium(ICGC)datasets.TCGA and ICGC datasets were used for screening prognostic genes along with developing and validating a seven-gene prognostic survival model by weighted gene coexpression network analysis and least absolute shrinkage and selection operator regression with Cox regression.The relative analysis of tumor mutation burden(TMB),TME cell infiltration,immune check-points,immune therapy,and functional pathways was also performed based on prognostic genes.RESULTS Seven prognostic genes were identified for signature construction.Survival receiver operating characteristic curve analysis showed the good performance of survival prediction.TMB could be regarded as an independent factor in HCC survival prediction.There was a significant difference in stromal score,immune score,and estimate score between the high-risk and low-risk groups stratified based on the risk score derived from the seven-gene prognostic model.Several immune checkpoints,including VTCN1 and TNFSF9,were found to be associated with the seven prognostic genes and risk score.Different combinations of checkpoint blockade targeting inhibitory CTLA4 and PD1 receptors and potential chemotherapy drugs hold great promise for specific HCC therapies.Potential pathways,such as cell cycle regulation and metabolism of some amino acids,were also identified and analyzed.CONCLUSION The novel seven-gene(CYTH3,ENG,HTRA3,PDZD4,SAMD14,PGF,and PLN)prognostic model showed high predictive efficiency.The TMB analysis based on the seven genes could depict the basic profile of the immune response in HCC,which might be worthy of clinical application. 展开更多
关键词 Hepatocellular carcinoma Prognostic model Weighted gene coexpression network analysis MICROenvironment CHEMOTHERAPY
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In Vivo Improvements in Facial Appearance and in Vitro Changes in Gene Expression Using a Topical Formulation Designed to Repair Environmentally Induced DNA Damage
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作者 Amaryllis Aganahi Richard Parker Yohei Tanaka 《Journal of Cosmetics, Dermatological Sciences and Applications》 2024年第2期141-173,共33页
Background: While sunscreen has been accepted as a mainline defence against photodamage from ultraviolet, visible light and near-infrared radiation, there appears to be a lack of research into photorepair. The concept... Background: While sunscreen has been accepted as a mainline defence against photodamage from ultraviolet, visible light and near-infrared radiation, there appears to be a lack of research into photorepair. The concept of protecting the skin during the day and repairing cellular damage at night is intuitive, yet specific strategies revolving around combinations of proven reparative active ingredients remain unelucidated. Purpose: To investigate the efficacy of a solar repair Formulation following ultraviolet and environmental exposure in order to improve overall skin health and appearance through three hypotheses: The Formulation increases expression of DNA repair mechanisms markers;The Formulation enhances overall skin appearance through reducing signs of inflammation, elevating hydration, reinforcing skin firmness and amplifying radiance;In-Vivo efficacy test results are aligned with measured gene expression changes. Methods: The Formulation (#6NIC1.V1.1-1) was tested for: In-vitro LDH cytotoxicity activity, In-vitro qPCR gene expression with and without ultraviolet exposure on a reconstructed 3-dimensional skin model, and In-Vivo efficacy study on a panel of 22 participants objectively and subjectively. Results: Skin radiance, firmness, hydration, redness, and inflammation are significantly improved after In-Vivo skin exposure to the Formulation and environmental challenges such as ultraviolet radiation. These outcomes were confirmed by in-vitro genetic testing on a reconstructed human skin model. Conclusion: The studies allowed us to identify and group results in four main skin functions that were significantly enhanced following the application of the Formulation: firmness, hydration, radiance and soothing. 展开更多
关键词 PHOTOPROTECTION Photorepair DNA Repair Anti-Photoaging gene Expression Antioxidant REJUVENATION
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Effects of thinning on the understory light environment of different stands and the photosynthetic performance and growth of the reforestation species Phoebe bournei 被引量:1
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作者 Shicheng Su Nianqing Jin Xiaoli Wei 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期12-28,共17页
Light levels determine regeneration in stands and a key concern is how to regulate the light environment of different stand types to the requirements of the understory.In this study,we selected three stands typical in... Light levels determine regeneration in stands and a key concern is how to regulate the light environment of different stand types to the requirements of the understory.In this study,we selected three stands typical in south China(a Cryptomeria japonica plantation,a Quercus acutissima plantation,and a mixed stand of both)and three thinning intensities to determine the best understory light environ-ment for 3-year-old Phoebe bournei seedlings.The canopy structure,understory light environment,and photosynthe-sis and growth indicators were assessed following thin-ning.Thinning improved canopy structure and understory light availability of each stand;species composition was the reason for differences in the understory light environ-ment.Under the same thinning intensity,the mixed stand had the greatest light radiation and most balanced spectral composition.P.bournei photosynthesis and growth were closely related to the light environment;all three stands required heavy thinning to create an effective and sustained understory light environment.In a suitable understory light environment,the efficiency of light interception,absorption,and use by seedlings was enhanced,resulting in a higher carbon assimilation the main limiting factor was stomatal conductance.As a shade-avoidance signal,red/far-red radia-tion is a critical factor driving changes in photosynthesis and growth of P.bournei seedlings,and a reduction increased light absorption and use capacity and height:diameter ratios.The growth advantage transformed from diameter to height,enabling seedlings to access more light.Our findings suggest that the regeneration of shade-tolerant species such as P.bournei could be enhanced if a targeted approach to thinning based on stand type was adopted. 展开更多
关键词 THINNING Understory light environment Phoebe bournei Photosynthetic performance Growth performance
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Design and Sizing of an Ecological Wastewater Treatment System in a School Environment: A Case Study of Ndiebene Gandiol 1 School
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作者 Falilou Coundoul Abdou Khafor Ndiaye +1 位作者 Abdoulaye Deme David de la Varga 《Journal of Water Resource and Protection》 CAS 2024年第1期41-57,共17页
The primary objective of this study was to design and size a sustainable sanitation solution for the Ndiebene Gandiol 1 school located in the eponymous commune in northern Senegal. Field investigations led to the coll... The primary objective of this study was to design and size a sustainable sanitation solution for the Ndiebene Gandiol 1 school located in the eponymous commune in northern Senegal. Field investigations led to the collection of wastewater samples. Their analysis revealed specific pollutant loads, including loads of BOD5 3.6966 kgO<sub>2</sub>/day and COD of 12.8775 kgO<sub>2</sub>/day, which were central to the design phase. Following a rigorous assessment of the existing sanitation infrastructure, constructed wetland (CWs) emerged as the most appropriate ecological solution. This system, valued for its ability to effectively remove contaminants, was tailored to the specific needs of the site. Consequently, the final design of the filter extends over 217.16 m<sup>2</sup>, divided into two cells of 108.58 m<sup>2</sup> each, with dimensions of 12.77 m in length and 8.5 m in width. The depth of the filtering medium is approximately 0.60 m, meeting the standards while ensuring maximized purification. Typha, an indigenous and prolific plant known for its purification abilities, was selected as the filtering agent. Concurrently, non-crushed gravel was chosen for its proven filtration capacity. This study is the result of a combination of scientific rigor and design expertise. It provides a holistic view of sanitation for Ndiebene Gandiol. The technical specifications and dimensions of the constructed wetland filter embody an approach that marries indepth analysis and practical application, all aimed at delivering an effective and long-lasting solution to the local sanitation challenges. By integrating precise scientific data with sanitation design expertise, this study delivers a holistic solution for Ndiebene Gandiol. The detailed dimensions and specifications of the constructed wetland filter reflect a methodology that combines meticulous analysis with practical adaptation, aiming to provide an effective and sustainable response to the challenges of rural and school sanitation in the northern region of Senegal. 展开更多
关键词 Water Review Hydraulic Engineering Water Treatment Agricultural Irrigation SANITATION Engineering environment
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Synthesis and nitrogen content regulation of diamond in a high-pressure hydrogen-rich environment
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作者 黄国锋 陈良超 房超 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期541-546,共6页
The regulating nitrogen content of diamond in a hydrogen-rich high-temperature and high-pressure(HPHT) growth environment was systematically investigated in this work by developing three growth systems,namely, "F... The regulating nitrogen content of diamond in a hydrogen-rich high-temperature and high-pressure(HPHT) growth environment was systematically investigated in this work by developing three growth systems,namely, "FeNi+Ti", "FeNi+G_(3)N_(6)H_(6)",and "FeNi+Ti+C_(3)N_(6)H_(6)".Optical microscopy,infrared spectroscopy,and photoluminescence(PL)spectroscopy measurements were conducted to analyze the spectroscopic characteristics of diamonds grown in these three systems.From our analysis,it was demonstrated that the presence of hydrogen in the sp^(3) hybrid C-H does not directly affect the color of the diamond and facilitates the increase of the nitrogen-vacancy(NV) center concentration in a highnitrogen-content diamond.In addition,titanium plays an important role in nitrogen removal,while its impact on hydrogen doping within the diamond lattice is insignificant.Most importantly,by regulating the ratio of nitrogen impurities that coexist in the nitrogen and hydrogen HPHT environment,the production of hydrogenous Ⅱa-type diamond,hydrogenous Ib-type diamond,and hydrogenous high-nitrogen-type diamonds was achieved with a nitrogen content of less than 1 ppm to 1600 ppm. 展开更多
关键词 DIAMOND HPHT superhard material hydrogen-rich environment
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Predict the evolution of mechanical property of Al-Li alloys in a marine environment
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作者 Wei Li Lin Xiang +6 位作者 Guang Wu Hongli Si Jinyan Chen Yiming Jin Yan Su Jianquan Tao Chunyang Huang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期557-566,共10页
The ocean is one of the essential fields of national defense in the future,and more and more attention is paid to the lightweight research of Marine equipment and materials.This study it is to develop a Machine learni... The ocean is one of the essential fields of national defense in the future,and more and more attention is paid to the lightweight research of Marine equipment and materials.This study it is to develop a Machine learning(ML)-based prediction method to study the evolution of the mechanical properties of Al-Li alloys in the marine environment.We obtained the mechanical properties of Al-Li alloy samples under uniaxial tensile deformation at different exposure times through Marine exposure experiments.We obtained the strain evolution by digital image correlation(DIC).The strain field images are voxelized using 2D-Convolutional Neural Networks(CNN)autoencoders as input data for Long Short-Term Memory(LSTM)neural networks.Then,the output data of LSTM neural networks combined with corrosion features were input into the Back Propagation(BP)neural network to predict the mechanical properties of Al-Li alloys.The main conclusions are as follows:1.The variation law of mechanical properties of2297-T8 in the Marine atmosphere is revealed.With the increase in outdoor exposure test time,the tensile elastic model of 2297-T8 changes slowly,within 10%,and the tensile yield stress changes significantly,with a maximum attenuation of 23.6%.2.The prediction model can predict the strain evolution and mechanical response simultaneously with an error of less than 5%.3.This study shows that a CNN/LSTM system based on machine learning can be built to capture the corrosion characteristics of Marine exposure experiments.The results show that the relationship between corrosion characteristics and mechanical response can be predicted without considering the microstructure evolution of metal materials. 展开更多
关键词 Marine environment Al-Li alloy Machine learning CORROSION
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Grain size and surface micro-texture characteristics and their paleoenvironmental significance of Holocene sediment in southern margin of the Gurbantunggut Desert,China
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作者 MA Yunqiang LI Zhizhong +2 位作者 TAN Dianjia ZOU Xiaojun TAO Tonglian 《Journal of Arid Land》 SCIE CSCD 2024年第5期632-653,共22页
The southern margin of the Gurbantunggut Desert,China,is characterized by alternating layers of aeolian and alluvial deposits.Investigating the characteristics of arenaceous sediment in this area is of significant imp... The southern margin of the Gurbantunggut Desert,China,is characterized by alternating layers of aeolian and alluvial deposits.Investigating the characteristics of arenaceous sediment in this area is of significant importance for understanding the interactive processes of wind and water forces,as well as the provenance of sediment.However,there are relatively few investigations on the characteristics of such sediment at present.In this study,we researched three aeolian-alluvial interactive stratigraphic profiles and different types of surface sediment on the desert-oasis transitional zone of southern margin of the Gurbantunggut Desert.Based on the optically stimulated luminescence(OSL)dating of aeolian sand and analyses of quartz sand grain size and surface micro-texture,we explored the aeolian-alluvial environmental change at southern margin of the desert in Holocene,as well as the provenance of sediment.The results indicated that the grain size characteristics of different types of sediment in the stratigraphic profiles were similar to those of modern dune sand,interdune sand,muddy desert surface soil,and riverbed sand.Their frequency curves were unimodal or bimodal,and cumulative probability curves were two-segment or three-segment,mainly composed of suspension load and saltation load.The quartz sand in the sediment at southern margin of the desert had undergone alternating transformation of various exogenic forces,with short transportation distance and time,and sedimentary environment was relatively humid.In Holocene,southern margin of the desert primarily featured braided river deposits,and during intermittent period of river activity,there were also aeolian deposits such as sand sheet deposits,stabilized dune deposits,and mobile dune deposits.The provenance for Holocene alluvial deposits at southern margin of the desert remains relatively constant,with the debris of the Tianshan Mountains being the primary provenance.Aeolian sand is mainly near-source recharge,which is formed by in situ deposition of fluvial or lacustrine materials in southern margin of the desert transported by wind erosion,and its provenance was still the weathered debris of the Tianshan Mountains.In addition,the sand in interior of the desert may be transported by northwest wind in desert-scale,thus affecting the development of dunes in southern margin of the desert.The results of this study provide a reference for understanding the composition and provenance changes of desert sand in the context of global climate change. 展开更多
关键词 aeolian-alluvial deposition grain size surface micro-texture sedimentary environment HOLOCENE
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Sedimentary Environment and Mineralization of the Black Shale Polymetallic Layer in the Early Cambrian,SW China:Constraints from in situ LA-ICP-MS Analysis of Pyrite
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作者 YANG Zhen FU Yong +2 位作者 LI Chao CAI Xi GUO Chuan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第2期416-429,共14页
A polymetallic layer is usually developed at the bottom of the early Cambrian black shale in Guizhou Province.The mineral that makes up the polymetallic layer is related to the sedimentary facies.To analyze the differ... A polymetallic layer is usually developed at the bottom of the early Cambrian black shale in Guizhou Province.The mineral that makes up the polymetallic layer is related to the sedimentary facies.To analyze the differentiation mechanism between polymetallic deposits(Ni-Mo and V),the Zhijin Gezhongwu profile located in the outer shelf and the Sansui Haishan V deposit located in the lower slope are selected to study the in situ sulfur isotopes and trace elements of pyrite.The results show that δ^(34)S values of pyrite vary widely from−7.8‰to 28‰in the Gezhongwu profile,while the δ^(34)S values are relatively uniform(from 27.8‰to 38.4‰)in the Haishan profile.The isotopic S composition is consistent with the transition that occurs in the sedimentary phase from the shelf to the deep sea on the transgressive Yangtze platform;this indicates that the δ^(34)SO_(4)^(2−)values in seawater must be differently distributed in depositional environments.The sulfur in the Ni-Mo layer is produced after the mixing of seawater and hydrothermal fluid,while the V layer mainly originates from seawater.Overall,the Ni-Mo and V deposits have been differentiated primarily on the basis of the combined effect of continental weathering and hydrothermal fluid. 展开更多
关键词 sedimentary environment black shale polymetallic layer PYRITE early Cambrian
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The chemical environment and structural ordering in liquid Mg-Y-Zn system:An ab-initio molecular dynamics investigation of melt for the formation mechanism of LPSO structure
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作者 Tangpeng Ma Jin Wang +5 位作者 Kaiming Cheng Chengwei Zhan Jixue Zhou Jingyu Qin Guochen Zhao Xinfang Zhang 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第2期815-824,共10页
In an effort to clarify the formation mechanism of LPSO structure in Mg-Y-Zn alloy,the chemical environment and structural ordering in liquid Mg-rich Mg-Y-Zn system are investigated with the aid of ab-initio molecular... In an effort to clarify the formation mechanism of LPSO structure in Mg-Y-Zn alloy,the chemical environment and structural ordering in liquid Mg-rich Mg-Y-Zn system are investigated with the aid of ab-initio molecular dynamics simulation.In liquid Mg-rich Mg-Y alloys,the strong Mg-Y interaction is determined,which promotes the formation of fivefold symmetric local structure.For Mg-Zn alloys,the weak Mg-Zn interaction results in the fivefold symmetry weakening in the liquid structure.Due to the coexistence of Y and Zn,the strong attractive interaction is introduced in liquid Mg-Y-Zn ternary alloy,and contributes to the clustering of Mg,Y,Zn launched from Zn.What is more,the distribution of local structures becomes closer to that in pure Mg compared with that in binary Mg-Y and Mg-Zn alloys.These results should relate to the origins of the Y/Zn segregation zone and close-packed stacking mode in LPSO structure,which provides a new insight into the formation mechanism of LPSO structure at atomic level. 展开更多
关键词 Mg-Y-Zn Chemical environment Structural ordering ab-initio molecular dynamics
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Environment Development and Health Safety System in Rural Areas of Bangladesh (Noakhali and Lakshmipur Districts)
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作者 Asif Kader 《Journal of Environmental Protection》 2024年第2期193-225,共33页
At present time, Bangladesh is developing its position in all sectors of world prosperity. Economic development of Bangladesh depends on working ability of whole population of this country, although Bangladesh is not ... At present time, Bangladesh is developing its position in all sectors of world prosperity. Economic development of Bangladesh depends on working ability of whole population of this country, although Bangladesh is not developed in health status of its whole population. A large percentage of people live in rural areas without any proper shelter. This study revealed the environmental development and health safety system in rural areas of Bangladesh, which is located in Noakhali and Lakshmipur districts of Bangladesh. Many sections were studied, which are the main structure of environmental development and health safety system of southeastern region of Bangladesh. The study found that there were three types of handicraft enterprises in the surveyed area such as handicraft input, like palm leaf, factories, Betel nut businesses, and Coconut businesses were headed and owned by the women and they were unaware of their health, environment and waste management or reduction of pollution. This study also reveals that microentrepreneurs did not ensure purified water supply and hygienic toilets within enterprises in the study area. The study also found that a significant portion of the microentrepreneurs are workers, and their family members were always fewer users of protective equipment during the COVID-19 pandemic. This study identified that most MEs faced transport or carrying facilities or big costing problems, including problems in available services for raw materials in the high category. In contrast, the high cost of transport facilities was very intensive in the study area. Moreover, it found that Microentrepreneurs (MEs) faced high product marketing costs for transport facilities, and a lack of proper pricing of the products in the study area. In addition, it explored that most of the microentrepreneurs did not receive sufficient credit support, and they faced negative attitudes and delayed responses from the credit services providers in the study area. It also found that the majority of the microentrepreneurs argued that capital support, loan, aid, technological assistance, infrastructural assistance, availability of skilled labor forces, availability of raw materials, and getting the government assistance and services were the major reasons for the highest growth of the enterprises in the study area. In addition, entire MEs had no knowledge and understanding of climate change in the study area. It is worth mentioning that MEs were not aware of climate change and its impacts on nature in the handicrafts sector and in their daily lives. A significant portion of the MEs took safety measures against risk and protected themselves and workers within the enterprises in the study area. MEs had various demands such as infrastructural development, economic assistance (/aid/loan/grants/financial), training and development, assistance for environment development, and machinery assistance for promoting their business. MEs argued that the implementation of their suggestion is the key to improve the current situation of the enterprises. The MEs suggested appointing expert workers, ensuring quality inputs, training workers and reserving products carefully. 展开更多
关键词 COVID-19 HANDICRAFT INGREDIENTS MICROENTERPRISE environment Climate-Change Waste-Management
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A CombustionModel for Explosive Charge Affected by a Bottom Gap in the Launch Environment
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作者 ShiboWu Weidong Chen +4 位作者 Jingxin Ma Lan Liu Shengzhuo Lu Honglin Meng Xiquan Song 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1207-1236,共30页
Launch safety of explosive charges has become an urgent problem to be solved by all countries in the world aslaunch situation of ammunition becomes consistentlyworse.However, the existing numericalmodels have differen... Launch safety of explosive charges has become an urgent problem to be solved by all countries in the world aslaunch situation of ammunition becomes consistentlyworse.However, the existing numericalmodels have differentdefects. This paper formulates an efficient computational model of the combustion of an explosive charge affectedby a bottom gap in the launch environment in the context of the material point method. The current temperatureis computed accurately from the heat balance equation, and different physical states of the explosive charges areconsidered through various equations of state. Microcracks in the explosive charges are described with respectto the viscoelastic statistical crackmechanics (Visco–SCRAM) model. Themethod for calculating the temperatureat the bottomof the explosive charge with respect to the bottomgap is described. Based on this combustionmodel,the temperature history of a Composition B (COMB) explosive charge in the presence of a bottom gap is obtainedduring the launch process of a 155-mm artillery. The simulation results show that the bottom gap thickness shouldbe no greater than 0.039 cm to ensure the safety of the COM B explosive charge in the launch environment. Thisconclusion is consistent with previous results and verifies the correctness of the proposed model. Ultimately, thispaper derives amathematical expression for themaximumtemperature of the COMB explosive chargewith respectto the bottomgap thickness (over the range of 0.00–0.039 cm), and establishes a quantitative evaluationmethod forthe launch safety of explosive charges.The research results provide some guidance for the assessment and detectionof explosive charge safety in complex launch environments. 展开更多
关键词 Combustion model explosive charge safety launch environment bottom gap TEMPERATURE
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Study on Distribution of Four Pseudomonas Species in Living Environment Using Multiplex PCR
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作者 Sachiyo Hayashi Koji Umezawa +12 位作者 Osamu Tsuzukibashi Akira Fukatsu Mana Fuchigami Chiaki Komine Hiroshi Yamamoto Mio Hagiwara-Hamano Yukiko Iizuka Satoshi Uchibori Masanobu Wakami Hiroshi Murakami Taira Kobayashi Masahiko Fukumoto Takato Nomoto 《Open Journal of Stomatology》 2024年第2期77-86,共10页
Purpose: The genus Pseudomonas is a ubiquitous microorganism frequently detected from immunocompromised patients. The inherent resistance to numerous antimicrobial agents contributes to the opportunistic character of ... Purpose: The genus Pseudomonas is a ubiquitous microorganism frequently detected from immunocompromised patients. The inherent resistance to numerous antimicrobial agents contributes to the opportunistic character of this pathogen exhaustive monitoring of this pathogen is considered of critical importance to public health organizations. The reliable identification method able to distinguish genetic close Pseudomonas species is needed, because these organisms are difficult to differentiate by phenotypic or biochemical methods. The purpose of the present study was to design species-specific primers in order to identify and detect four Pseudomonas species which are frequently detected from the human oral cavities, and to investigate the distribution of these organisms in the living environment using a multiplex PCR. Methods: Polymerase chain reaction (PCR) primers were designed based on partial sequences of the rpoD gene of four Pseudomonas species. Swab samples were collected from fifty washstands, and the distribution of Pseudomonas species was investigated using a conventional PCR at genus level and a multiplex PCR at species level. Results: Multiplex PCR method developed in this study was able to distinguish four Pseudomonas species clearly. The genus Pseudomonas was detected from all samples (100%), whereas P. putida, P, aeruginosa, P. stutzeri and P. fluorescens were detected at 44%, 8%, 4% and 2% in fifty swab samples, respectively. Conclusion: Our developed one-step multiplex PCR method is accurate, specific, cost-effective, time-saving, and works without requiring DNA extraction. It was indicated that washstands were the uninhabitable environment for P. putida, P, aeruginosa, P. stutzeri and P. fluorescens. 展开更多
关键词 Genus Pseudomonas Multiplex PCR Living environment
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Ecological Wastewater Treatment System in a School Environment Using a Horizontal Flow Biological Reactor: The Case of Typha
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作者 Falilou Coundoul Abdou Khafor Ndiaye Abdoulaye Deme 《Journal of Environmental Protection》 2024年第1期1-12,共12页
The overarching goal of this study is to offer an effective and sustainable solution to the challenges of sanitation in rural and school settings in the northern region of Senegal. The study explores a wastewater trea... The overarching goal of this study is to offer an effective and sustainable solution to the challenges of sanitation in rural and school settings in the northern region of Senegal. The study explores a wastewater treatment approach based on phytoremediation, with a particular focus on the use of horizontally-flowing reed bed filters. Furthermore, it aims to adapt and optimize these systems for the specific needs of Senegal, focusing on wastewater in school environments. Thus, we constructed a horizontally-flowing reed bed filter, planted with Typha, at the Ndiébène Gandiol school in Senegal. We will investigate the efficiency of wastewater treatment by this horizontally-flowing reed bed filter, emphasizing the role of the plant used: Typha. The filter is described in detail, specifying its dimensions, its composition of flint gravel, and the choice of plants, namely Typha. The experimental protocol is detailed, describing the sampling at the entrance and exit of the filter to evaluate water quality. The parameters analyzed include Chemical Oxygen Demand (COD), Biochemical Oxygen Demand over 5 days (BOD5), suspended solids, ammonium, nitrates, phosphates, pH, conductivity, and fecal coliforms. The results indicate a significant improvement in water quality after treatment. COD, BOD5, suspended solids, and fecal coliforms are greatly reduced, thus demonstrating the efficacy of the Typha filter. However, nitrate concentrations remain relatively stable, suggesting room for improvement in their elimination. A perspective of reuse of the treated water is considered, showing that the effluents from the planted filter meet Senegalese and international standards for irrigation. The findings suggest that these waters could be used for a variety of crops, thereby reducing the pressure on freshwater resources. In conclusion, the Typha-based filtration system shows promising results for improving water quality in this region of Senegal. However, adjustments are necessary for more effective nitrate removal. This study paves the way for sustainable use of treated wastewater for irrigation, thus contributing to food security and the preservation of water resources. 展开更多
关键词 Hydraulic Engineering Wastewater Quality Wastewater Treatment Agricultural Irrigation SANITATION Engineering environment
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Research Progress of Microplastics Pollution in Environment
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作者 Peng WAN Zhen ZHAO +3 位作者 Guoyan WEN Yunshuang FU Cuizhi LI Xiaoli WU 《Asian Agricultural Research》 2024年第4期19-22,共4页
Microplastics pollution has become one of the focuses of global environmental science research.Microplastics include micro plastic particles and nano-plastic particles,which come from the decomposition of plastic prod... Microplastics pollution has become one of the focuses of global environmental science research.Microplastics include micro plastic particles and nano-plastic particles,which come from the decomposition of plastic products,the release of microfibers and the industrial process of plastic particles.The distribution of microplastics in water,soil and atmosphere is summarized,and the widespread existence of microplastics in different environmental media is emphasized.This paper also summarizes the potential impact of microplastics on ecosystems and organisms,and pays attention to the transmission and accumulation of microplastics in the food chain,as well as its potential threat to human health.Finally,the paper discusses the methods and technologies of microplastics treatment and monitoring at present,and puts forward the direction of further research on microplastics pollution in order to formulate more effective management and mitigation strategies. 展开更多
关键词 Microplastics environment POLLUTION
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