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Development of Soil Crusts Under Simulated Rainfall and Crust Formation on a Loess Soil as Influenced by Polyacrylamide

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Pedosphere 2012年第3期22卷 415-424页

作者： hu Xia LIU lian-You LI Shun-Jiang CAI Qiang-Guo LU Yan-Li GUO Jin-rui State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875(China) Academy of Disaster Reduction and Emergency Management Beijing Normal UniversityBeijing 100875(China) Institute of Plant Nutrition and Resources Beijing Academy of Agriculture and Forestry SciencesBeijing 100097(China) Institute of Geographical Science and Natural Resources Research Chinese Academy of SciencesBeijing 100101(China)

This study evaluated the morphological characteristics and dynamic variation in characteristics of soil crust and iden-tified the relationships between soil crust and splash erosion under simulated *** effect of polyacrylamide (PAM) on soil aggregate stabilization and crust formation was also investigated.A laboratory rainfall simulation experiment was carried out using soil sample *** slices were examined under a polarized light microscopy and a scanning electron microscope (SEM).The results revealed that the soil crusts were thin and were characterized by a greater density,higher shear strength,finer porosity,and lower saturated hydraulic conductivity than the underlying *** types of crusts,i.e.,structural and depositional crusts,were *** texture was determined to be the most important soil variable influ-encing surface crust formation;depositional crust formation was primarily related to the skeleton characteristics of the soil and happened when the soil contained a high level of medium and large *** crust formation processes observed were as follows:1) The fine particles on the soil surface became spattered,leached,and then rough in response to raindrop impact and 2) the fine particles were washed into the subsoil pores while a compact dense layer concurrently formed at soil surface due to the continual compaction by the ***,the factors that influenced structural crust formation were a large amount of fine particles in the soil surface,continual impact of raindrops,dispersion of aggregates into fine particles,and the formation of a compact dense layer concurrently at the soil *** was concluded that the most important factor in the formation of soil crusts was raindrop *** polyacrylamide (PAM) was applied,it restored the soil structure and greatly increased soil aggregate *** effectively prevented crust ***,this function of PAM was not continuously effective and

关键词： depositional crust raindrop impact soil aggregates splash erosion structural crust

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Furazolidone,amoxicillin,bismuth and rabeprazole quadruple rescue therapy for the eradication of Helicobacter pylori

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World Journal of Gastroenterology 2009年第7期15卷 860-864页

作者： Hong Cheng Fu-lian hu Department of Gastroenterology Peking University First Hospital Beijing 100034 China

AIM： To compare the efficacy and side effect profiles of three furazolidone and amoxicillin-based quadruple rescue therapies for the eradication of Helicobacter pylori （H pylonS. METHODS： Patients who failed in the Hpylori eradication therapy for at least one course were randomly allocated into three groups. Group A received rebaprazole 10 mg＋ amoxicillin 1 g ＋ furazolidone 100 mg, and bismuth subcitrate 220 mg, twice daily for 1 wk; group B received the same regimen of group A but for 2 wk; and group C received the same regimen of group B, but furazolidone was replaced by furazolidone 100 mg three times daily. To record the side effect profiles at the end of the treatment, Hpylori eradication was assessed with 13C-urea breath test 4 wk after therapy. RESULTS： Sixty patients were enrolled including 28 males, and 20 patients in each group. The average age of the patients was 49.2 years, ranging from 18 to 84 years. H pylori eradication rates with per-protocol analysis were 82%, 89% and 90% in the three groups, respectively. Side effects were found in 11 patients, including mild dizziness, nausea, diarrhea and increased bowel movement. None of the 11 patients needed treatment for their side effects. CONCLUSION： One- or two-week furazolidone and amoxicillin-based quadruple rescue therapy with a low dose furazolidone （100 mg bid） for the eradication of Hpylori is effective. Extending the antibiotic course to 14 d could improve the eradication rates.

关键词： Helicobacter pylori Rescue therapy Quadruple therapy Furazolidone Low dose

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Effect of Seasonality on Distribution of Macroalgae in a Stream System(Xin'an Spring) in Shanxi Province,North China

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Journal of Integrative Plant Biology 2006年第8期48卷 889-896页

作者： Bian-Fang hu Shu-lian Xie School of Life Science and Technology Shanxi University Taiyuan 030006 China

A survey of the seasonal distribution of macroalgae in a stream system in Shanxi Province, north China, was undertaken from July 2004 to April 2005. The relative abundance and percentage cover of macroalgae, and several environmental factors were monitored along a 20-m stretch at each of four sites, at intervals of approximately three months （one sampling per season）. Several stream conditions were relatively constant over the sampling period （pH, maximum width and maximum depth）, whereas others exhibited a distinct seasonal pattern （water temperature and specific conductance）, and some fluctuated with no discernable seasonal pattern （current velocity and dissolved oxygen）. Forty-two species of macroalgae were found, with a predominance of Chlorophyta （26 species, 61.9%）. Rhodophyts and Charophyta represented the smallest proportion （1 species each, 2.38%）. Six macroalgae species were the most widespread, occurring in all four sampling sites. Twelve species were found at only one site each. In terms of seasonality, eight species occurred throughout the year, whereas 16 species were found in only one season each. The macroalgal community at Xin＇an Spring was species rich relative to other streams. Species richness per sampling site was negatively correlated with pH. Principal component analysis revealed that no single variable had much influence on the macroalgal seasonal dynamics. We calculated Sorensen similarity indices to compare our study with other continent-wide surveys of stream macroalgae, but the similarity indices were all very low. This study also shows that macroalgae in different locations have significant reproductive isolation.

关键词： China distribution environmental factors seasonality stream macroalgae.

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The New Methods for Characterization of Molecular Weight of Supramolecular Polymers

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Chinese Journal of Polymer Science 2024年第10期42卷 1403-1413,I0006页

作者： hui Liu rui hu Zi-Qing hu Xiao-Fan Ji Key Laboratory of Materials Chemistry for Energy Conversion and Storage Ministry of EducationHubei Key Laboratory of Materials Chemistry and Service FailureHubei Engineering Research Center for Biomaterials and Medical Protective MaterialsSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan430074China

Supramolecular polymers,as a type of dynamic polymers,are subordinate to the interdisciplinary field of polymer chemistry and supramolecular chemistry,whose development has greatly promoted the prosperity of new ***,molecular weight is one of the most important parameters of supramolecular polymers,which affects the physical/chemical properties and processing applications of *** new methods for characterizing the molecular weight of supramolecular polymers is crucial for advancing the development of supramolecular *** this review,we elaborate and summarize three strategies for characterizing the molecular weight of supramolecular polymers that recently reported by our research group according to the characteristics of supramolecular polymers,including(1)the molecular weight distinction corresponding to variable fluorescence colors,(2)matching different molecular weights with different fluorescence lifetime,(3)transforming supramolecular polymers into mechanically interlocked polymers or covalent ***,we also discuss the limitations of current methods for characterizing supramolecular *** hope that this review can promote the development of supramolecular polymers and significantly inspire to exploit new methods to characterizing molecular weight of supramolecular polymers.

关键词： Supramolecular polymers Molecular weight Self-assembly Mechanically interlocked polymers Dynamic polymers

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Role of two phosphohexomutase genes in glycogen synthesis in Synechocystis sp. PCC6803

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Chinese Science Bulletin 2013年第36期58卷 4616-4621页

作者： LIU lian hu Hanhua GAO Hong XU XuDong State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences

Phosphohexomutases catalyze the interconversion between hexose-6-phosphate and hexose-1-phosphate and play important roles in polysaccharide *** Synechocystis *** 6803,sll0726 is predicted to encode PGM(phosphoglucomutase),slr1334is predicted to encode a PGM/PMM(phosphomannomutase)bifunction *** comparison to the wild type,a sll0726-null mutant showed 3.4%PGM activity but 45%–69%glycogen ***-regulation of slr1334,an essential gene,by using a copper regulated promoter further decreased the PGM activity in the sll0726::KmrPpetE-slr1334 double mutant to 0.3%of the wild type ***,the glycogen content was not further decreased in *** vitro,recombinant Sll0726 or Slr1334 showed predicted enzyme *** results indicate that a relatively high level of glycogen can be maintained in Synechocystis mutants with low levels of PGM *** high PGM activity in the cyanobacterium may be required for turnover of glycogen or synthesis of other polysaccharides or oligosaccharides.

关键词：糖原合成集胞藻 e基因铂族金属多糖合成金属活性调控启动子突变体

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Main geological and mining factors affecting ground cracks induced by underground coal mining in Shanxi Province, China

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International Journal of Coal Science & Technology 2020年第2期7卷 362-370页

作者： Xugang lian Haifeng hu Tao Li Dongsheng hu School of Mining Engineering Taiyuan University of TechnologyTaiyuan030024ShanxiChina Geological Survey Department Yangquan Coal Industry(Group)Co.Ltd.Yangquan045000ShanxiChina

As one of the largest coal-rich provinces in China,Shanxi has extensive underground coal-mining *** operations have caused numerous ground cracks and substantial environmental *** study the main geological and mining factors influencing mining-related ground cracks in Shanxi,a detailed investigation was conducted on 13 mining-induced surface cracks in *** on the results,the degrees of damage at the study sites were empirically classified into serious,moderate,and minor,and the influential geological and mining factors(e.g.,proportions of loess and sandstone in the mining depth,ratio of rock thickness to mining thickness,and ground slope)were *** to the analysis results,three factors(proportion of loess,ratio of rock thickness to mining thickness,and ground slope)play a decisive role in ground cracks and can be respectively considered as the critical material,mechanical,and geometric conditions for the occurrence of mining surface ***,these three factors have a strong influence on the occurrence of serious discontinuous ground *** results can be applied to help prevent and control ground damage caused by coal *** findings also provide a direct reference for predicting and eliminating hidden ground hazards in mining areas.

关键词： Loess layer Main geological and mining factors Ground cracks Ground slope Underground coal mining

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新疆和田地区社区居民心理健康服务需求现状及影响因素

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中国健康心理学杂志 2025年第1期33卷 8-15页

作者：李娜杨睿胡浩洋新疆警察学院马克思主义学院(乌鲁木齐) 830011 新疆警察学院侦查系新疆和田地委政法委

目的:了解和田地区社区居民心理健康服务需求状况并探讨其影响因素,为开展心理健康服务工作提供科学依据。方法:抽取和田地区4个不同县市8个社区1600名社区居民为调查对象,使用自编的社区居民心理健康服务需求问卷进行调查。了解社区居... 详细信息

目的:了解和田地区社区居民心理健康服务需求状况并探讨其影响因素,为开展心理健康服务工作提供科学依据。方法:抽取和田地区4个不同县市8个社区1600名社区居民为调查对象,使用自编的社区居民心理健康服务需求问卷进行调查。了解社区居民在服务态度、服务内容、服务方式、服务途径、服务人员、服务机构方面的需求,运用多元线性回归分析的方法分析心理健康服务需求的影响因素。结果:和田地区社区居民对心理健康服务需求的总均值为2.90。86.1%社区居民希望社区心理健康服务中心提供心理健康服务,83.8%社区居民希望社区心理健康服务人员提供心理健康服务。居住在农村的居民对心理健康服务需求的得分最高(F=37.954,P<0.001);受教育程度为初中及以下和高中的居民对心理健康服务需求的得分较高(F=13.260,P<0.001);月收入在2000元以下和2000~3999元的居民对心理健康服务需求的得分较高(F=13.748,P<0.001);已婚居民比未婚居民对心理健康服务需求的得分高(F=3.236,P<0.05)。多元线性回归分析显示:居住地(镇中心区)、居住地(镇乡结合区)、居住地(主城区)、婚姻状况(已婚)、月收入水平是影响居民对心理健康服务需求的主要因素。B值及其95%CI分别为-0.170(-0.236~-0.103)、-0.429(-0.519~-0.340)、-0.336(-0.409~0.263)、0.115(0.037~0.192)、-0.051(-0.083~-0.019)。结论:和田地区社区居民心理健康服务需求较高,居民选择社区心理健康服务中心及人员提供心理健康服务的比例较大。低学历、低收入、农村、已婚居民对心理健康服务的需求较大。居住地、婚姻状况、月收入水平是居民心理健康服务需求的主要影响因素。

关键词：社区居民心理健康服务需求心理服务体系建设多元线性回归分析

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Changes in Global DNA Methylation Intensity and DNMT1 Transcription During the Aging Process of Scallop Chlamys farreri

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Journal of Ocean University of China 2015年第4期14卷 685-690页

作者： lian Shanshan HE Yan LI Xue ZHAO Bosong HOU rui hu Xiaoli ZHANG Lingling BAO Zhenmin Key Laboratory of Marine Genetics and Breeding(MGB) of Ministry of Education College of Marine Life Sciences Ocean University of China

DNA methylation is an important epigenetic regulatory mechanism that influences genomic stability, gene activation, X-chromosome inactivation and other factors. A change in DNA methylation is usually associated with aging and cellular senescence. DNA methyltransferase 1(DNMT1) is the most abundant DNA methyltransferase, and it plays an important role in maintaining the established methylation pattern during DNA replication in vertebrates. Although the effect of aging on DNA methylation has been well studied in vertebrates, little research has been conducted in invertebrates, especially in marine bivalves. In this study, we examined global DNA methylation levels in four groups of adult Zhikong scallop Chlamys farreri at different ages. The results showed that both the age and tissue type had a strong effect on the DNA methylation. In addition, a significant decrease in DNA methylation with aging(1–4 years) can be detected in mantle, kidney and hepatopancreas. We further measured the change in DNMT1 transcript abundance using quantitative reverse transcription PCR(q RT-PCR), which revealed that DNMT1 transcription significantly decreased with aging in mantle and hepatopancreas and strongly correlated with DNA methylation(R = 0.72). Our data provided greater insight into the aging-related decline of DNA methylation, which could aid in gaining a better understanding of the relationship between DNA methylation and the aging process in bivalve mollusks.

关键词： aging DNA methylation DNMT1 transcription Chlamysfarreri

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Lateral epitaxial grown of two-dimensional halide perovskite heterostructures

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Rare Metals 2020年第8期39卷 863-864页

作者： Cheng-rui Shao Wei hu School of Physics and Electronics Hunan UniversityChangsha 410083China

In last decade,the halide perovskite materials have been widely explored all over the world for their excellent optoelectronic *** perovskite solar cells in particular are reshaping the landscape of ***,the perovskite... 详细信息

关键词： properties. perovskite landscape

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Properties of Collagen/Sodium Alginate Hydrogels for Bioprinting of Skin Models

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Journal of Bionic Engineering 2023年第1期20卷 105-118页

作者： Tian Jiao Qin lian Weilong lian Yonghui Wang Dichen Li rui L.Reis Joaquim Miguel Oliveira State Key Laboratory for Manufacturing System Engineering Xi’an Jiaotong UniversityXi’an710049China Shaanxi Ketao-AM Technology Co. Ltd.Xi’an710100China B’s Research Group I3Bs—Research Institute on BiomaterialsBiodegradables and BiomimeticsHeadquarters of the European Institute of Excellence on Tissue Engineering and Regenerative MedicineUniversity of MinhoBarco4805-017GuimarãesPortugal ICVS/3B’s–PT Government Associate Laboratory Barco4805-017GuimarãesPortugal

3D printing technology has great potential for the reconstruction of human ***,the reconstructed skin has some differences from natural skin,largely because the hydrogel used does not have the appropriate biological and physical properties to allow healing and *** study examines the swelling,degradability,microstructure and biological properties of Collagen/Sodium Alginate(Col/SA)hydrogels of differing compositions for the purposes of skin *** the content of sodium alginate causes the hydrogel to exhibit stronger mechanical and swelling properties,a faster degradation ratio,smaller pore size,and less favorable biological *** optimal 1%collagen hydrogel was used to print bi-layer skin in which fibroblasts and keratinocytes showed improved spreading and proliferation as compared to other developed *** Col/SA hydrogels presented suitable tunability and properties to be used as a bioink for bioprinting of skin aiming at finding applications as 3D models for wound healing research.

关键词： Bioink Bioprinting-Collagen sodium alginate hydrogel-Skin Wound healing Bionic

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