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Effects of long-term phosphorus fertilization and straw incorporation on phosphorus fractions in subtropical paddy soil

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Journal of Integrative Agriculture 2015年第2期14卷 365-373页

作者： li yu-yuan YANG Rui GAO Ru WEI Hong-an CHEN An-lei li Yong Key Laboratory of Agro-Ecological Processes in Subtropical Region Institute of Subtropical Agriculture Chinese Academy of Sciences School of Environmental and Municipal Engineering Xi'an University of Architecture and Technology

Study on soil phosphorus（P） fraction is an important aspect in probing the mechanisms of soil P accumulation in farmland and mitigating its losing risk to the environment. We used a sequential extraction method to evaluate the impacts of long-term fertilization and straw incorporation on inorganic, organic, and residual P（Pi, Po, and Pre） fractions in the plow layer（0–20 cm） of acidic paddy soil in southern China. The experiment comprised of six treatments：（i） no fertilizer control（CK）;（ii） straw incorporation and green manure（SG）;（iii） nitrogen and P fertilizer（NP）;（iv） NP＋SG;（v） NP＋K fertilizer（NPK）; and（vi） NPK＋SG. The results showed that, compared to the initial total soil P content（TSP, 600 mg kg^–1 in 1990）, long-term（20 years） combined continuous P fertilizer and SG significantly increased P accumulation（by 13–20%） while single fertilization（39.3 kg P ha^–1 yr^–1） could maintain soil P status at the most. The average soil P fractions comprised of extractable Pi, Po, and Pre by 51.7, 33.4, and 14.9% in total soil P, respectively. With comparison of no fertilizer addition（CK）, long-term single fertilization significantly（P〈0.05） increased the accumulation of Na HCO3^–, Na OH^–, and HCl^– extractable Pi fractions accounting for two- to three-fold, while SG increased the accumulation of Na HCO3^– and Na OH^– extractable Piand Po accounting for 12–60%. Though the mobilization of Pre fractions was not significant（P〉0.05）, our data indicate that SG may partially substitute for fertilizer P input and minimizing soil P accumulation and subsequent environmental risk in the subtropical paddy soil.

关键词： soil organic P soil inorganic P sequential extraction method soil P accumulation soil P mobilization manure application

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An experimental study on fracture mechanical behavior of rock-like materials containing two unparallel fissures under uniaxial compression

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Acta Mechanica Sinica 2016年第3期32卷 442-455页

作者： Yan-Hua Huang Sheng-Qi Yang Wen-ling Tian Wei Zeng li-yuan yu State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and Technology

Strength and deformability characteristics of rock with pre-existing fissures are governed by cracking behavior. To further research the effects of pre-existing fissures on the mechanical properties and crack coalescence process, a series of uniaxial compression tests were carried out for rock-like material with two unparallel *** the present study, cement, quartz sand, and water were used to fabricate a kind of brittle rock-like material cylindrical model specimen. The mechanical properties of rock-like material specimen used in this research were all in good agreement with the brittle rock materials. Two unparallel fissures（a horizontal fissure and an inclined fissure） were created by inserting steel during molding the model *** all the pre-fissured rock-like specimens were tested under uniaxial compression by a rock mechanics servocontrolled testing system. The peak strength and Young＇s modulus of pre-fissured specimen all first decreased and then increased when the fissure angle increased from 0？to 75？.In order to investigate the crack initiation, propagation and coalescence process, photographic monitoring was adopted to capture images during the entire deformation ***, acoustic emission（AE） monitoring technique was also used to obtain the AE evolution characteristic of prefissured specimen. The relationship between axial stress, AE events, and the crack coalescence process was set up： when a new crack was initiated or a crack coalescence occurred, thecorresponding axial stress dropped in the axial stress–time curve and a big AE event could be observed ***, the mechanism of crack propagation under microscopic observation was discussed. These experimental results are expected to increase the understanding of the strength failure behavior and the cracking mechanism of rock containing unparallel fissures.

关键词： Rock-like material Two unparallel fissures Mechanical parameters Crack evolution Acoustic emission(AE)

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Correlation between the rock mass properties and maximum horizontal stress:A case study of overcoring stress measurements

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 39-48页

作者： Peng li Meifeng Cai Shengjun Miao yuan li yu Wang Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and TechnologyXuzhou 221116China

Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress *** investigate the correlation between the rock mass properties and maximum horizontal stress,the three-dimensional(3D)stress tensors at 89 measuring points determined using an improved overcoring technique in nine mines in China were adopted,a newly defined characteristic parameter C_(ERP)was proposed as an indicator for evaluating the structural properties of rock masses,and a fuzzy relation matrix was established using the information distribution *** results indicate that both the vertical stress and horizontal stress exhibit a good linear growth relationship with *** is no remarkable correlation between the elastic modulus,Poisson's ratio and depth,and the distribution of data points is scattered and ***,there is no obvious relationship between the rock quality designation(RQD)and *** maximum horizontal stress σ_(H) is a function of rock properties,showing a certain linear relationship with the C_(ERP)at the same *** addition,the overall change trend of σ_(H) determined by the established fuzzy identification method is to increase with the increase of C_(ERP).The fuzzy identification method also demonstrates a relatively detailed local relationship betweenσ_H and C_(ERP),and the predicted curve rises in a fluctuating way,which is in accord well with the measured stress data.

关键词： overcoring stress measurements elastic modulus Poisson's ratio rock quality designation maximum horizontal stress fuzzy identification

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The association between retinal vasculature changes and stroke:a literature review and Meta-analysis

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International Journal of Ophthalmology(English edition) 2017年第1期10卷 109-114页

作者： Hui-Qun Wu Huan Wu li-li Shi li-yuan yu li-yuan Wang Ya-Lan Chen Jin-Song Geng Jian Shi Kui Jiang Jian-Cheng Dong Department of Medical Informatics Medical School of Nantong UniversityNantong 226001Jiangsu ProvinceChina Nantong University Division of Cooperative Research Centeron Evidence-based Medicine by Ministry of Education inChina Nantong 226001Jiangsu ProvinceChina Department of Ophthalmology Affiliated Hospital of Nantong UniversityNantong 226001Jiangsu ProvinceChina

AIM： To determine the association between retinal vasculature changes and ***： MEDliNE and EMBASE were searched for relevant human studies to September 2015 that investigated the association between retinal vasculature changes and the prevalence or incidence of stroke; the studies were independently examined for their qualities. Data on clinical characteristics and calculated summary odds ratios （ORs） were extracted for associations between retinal microvascular abnormalities and stroke, including stroke subtypes where possible, and adjusted for key variables. RESULTS： Nine cases were included in the study comprising 20 659 patients, 1178 of whom were stroke patients. The retinal microvascular morphological markers used were hemorrhage, microaneurysm, vessel caliber, arteriovenous nicking, and fractal dimension. OR of retinal arteriole narrowing and retinal arteriovenous nicking and stroke was 1.42 and 1.91, respectively, indicating that a small-caliber retinal arteriole and retinal arteriovenous nicking were associated with stroke. OR of retinal hemorrhage and retinal microaneurysm and stroke was 3.21 and 3.83, respectively, indicating that retinal microvascular lesions were highly associated with stroke. Results also showed that retinal fractal dimension reduction was associated with stroke （OR： 2.28 for arteriole network, OR： 1.80 for venular network）.CONCLUSION： Retinal vasculature changes have a specific relationship to stroke, which is promising evidence for the prediction of stroke using computerized retinal vessel analysis.

关键词： retinal image vasculature stroke Meta-analysis

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Epigenetic regulation by long noncoding RNAs in osteo-/adipogenic differentiation of mesenchymal stromal cells and degenerative bone diseases

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World Journal of Stem Cells 2022年第1期14卷 92-103页

作者： Kai Xia li-yuan yu Xin-Qi Huang Zhi-He Zhao Jun liu State Key Laboratory of Oral Diseases&National Clinical Research Center for Oral Diseases West China Hospital of StomatologySichuan UniversityChengdu 610041Sichuan ProvinceChina Department of Orthodontics West China Hospital of StomatologySichuan UniversityChengdu 610041Sichuan ProvinceChina

Bone is a complex tissue that undergoes constant remodeling to maintain homeostasis,which requires coordinated multilineage differentiation and proper proliferation of mesenchymal stromal cells(MSCs).Mounting evidence indicates that a disturbance of bone homeostasis can trigger degenerative bone diseases,including osteoporosis and *** addition to conventional genetic modifications,epigenetic modifications(i.e.,DNA methylation,histone modifications,and the expression of noncoding RNAs)are considered to be contributing factors that affect bone *** noncoding RNAs(lncRNAs)were previously regarded as‘transcriptional noise’with no biological ***,substantial evidence suggests that lncRNAs have roles in the epigenetic regulation of biological processes in MSCs and related *** this review,we summarized the interactions between lncRNAs and epigenetic modifiers associated with osteo-/adipogenic differentiation of MSCs and the pathogenesis of degenerative bone diseases and highlighted promising lncRNA-based diagnostic and therapeutic targets for bone diseases.

关键词： Long noncoding RNA Epigenetics DNA methylation Histones Cell differentiation Bone diseases

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Resistance of Cement-based Grouting Materials with Nano- SiO_(2) Emulsion to Chloride Ion Penetration

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 114-119页

作者： li Shuiping CHENG Jian WEI Chao yuan Bin yu Chengxiao College of Architectural Science and Engineering Yangzhou UniversityYangzhou 225127China

The chloride penetration resistance of cement-based grout materials was improved by nano-silica *** of mixtures containing different nano-silica particles or emulsions were exposed in sodium chloride solutions of specific concentrations with different test *** properties of the mixes were assessed in terms of weight loss and compressive strength.X-ray diffraction(XRD)and scanning electron microscopy(SEM)of mixes were performed to analysis the phase evolution and *** results demonstrated that the introduction of nano-SiO_(2) emulsion significantly decreased the compressive strength loss and calcium hydroxide(CH)crystal content of hydration production,and then enhanced the resistance of cement-based grouting materials to chloride ion *** improvement derives from the filling and pozzolanic effects of nano-SiO_(2) particles,which were incorporated via an emulsion and attributed to a well dispersion in grouting matrix.

关键词： grouting materials nano-SiO_(2)emulsion chloride ion penetration,weight loss strength loss

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Two-Dimensional Optical Lattice Solitons in Photovoltaic-Photorefractive Crystals

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Chinese Physics Letters 2012年第8期29卷 127-130页

作者： GUO Jian-Bang LU Ke-Qing NIU Ping-Juan yu li-yuan XING Hai-Ying State Key Laboratory of Transient Optics and Photonics Xi'an Institute of Optics and Precision MechanicsChinese Academic of SciencesXi'an 710119 School of Electronics and Information Engineering Tianjin Polytechnic UniversityTianjin 300160

We study two families of two-dimensional bright lattice solitons in photovoltaic-photorefractive *** is shown that self-focusing and self-defocusing lattice solitons are possible only when their power level exceeds a critical *** is found that self-focusing lattice solitons exist not only in the semi-infinite band gap,but also in the first band gap,whereas self-defocusing lattice solitons exist only in the first band *** structures of these lattice solitons are also *** results indicate that a self-focusing lattice soliton in the semi-infinite band gap is more confined than in the first band gap so its tails in the first band gap occupy many lattice sites;when a self-defocusing lattice soliton is close to the second band,the self-defocusing lattice soliton is more confined so its tails occupy a few lattice sites.

关键词： soliton lattice solitons

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Initial Approach to the Cellular Irradiation Injury of Human Pancreatic Carcinoma Cell line MIA PaCa-2 by High Dose per Fraction

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Clinical oncology and cancer researeh 2010年第6期7卷 352-358页

作者： Zhi-zhen WANG Hai-li yu Zhi-yong yuan Ping WANG Department of Radiation Therapy Tianjin Medical University Cancer Institute and Hospital Tianjin Key Laboratory of Cancer Prevention and Therapy Tianjin 300060 China.

OBJECTIVE To investigate an initial approach of radiotherapy, which produces cellular radiation injury by high dose in one fraction. METHODS Human pancreatic carcinoma cell line MIA PaCa-2, was cultivated and divided into 5 groups： 0, 2, 5, 10, 17 Gy. Cultivated cells were irradiated by 6MV-X ray in one fraction. Analysis were done as follows： comet assay, which assessed the level of DNA damage in the treated cells right after the cell was irradiated, flow cytometry, which was performed at 0, 6, 12, 24, 36 h after the cell line treated to ladder, which quantitatively asses changes of its cell cycle, DNA assessed the degree of DNA injury after 6 and 12 h, and histological examination, which analyzed cellular morphology after 24 h. RESULTS （1） After X-ray irradiated, the morphological change of human pancreatic carcinoma cell line （MIA PaCa-2） was mainly swelling. （2） When the dose of radiation was lower than 10 Gy, increasing the dose could greatly improve cell necrosis, apoptosis and blockage of cell cycle in GJM phase, which was consistent with the theory of radiation biology. （3） When radiation dose was more than the 10 Gy, the peak of apoptotic necrosis appeared strong and early. （4） The degree of DNA injury was also related to the dose of radiation therapy and most obvious in the 10 Gy group and not so obvious in the 17 Gy group. （5） When dose was less than 10 Gy, DNA ladder was a single electrophoretic band; in the 10 Gy group, the electrophoresis showed a multiple ladder band; when dose was more than 10 Gy, a vague and irregular band appeared on the electrophoresis. CONCLUSION Oncotic necrosis may be the main cell death style when dose per fraction is high, which differs from conventional dose fraction radiation therapy.

关键词： dose-response relationship drug necrosis irradiation injury.

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Orthodontic retreatment of an adult woman with mandibular backward positioning and temporomandibular joint disorder:A case report

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World Journal of Clinical Cases 2022年第2期10卷 691-702页

作者： li-yuan yu Kai Xia Wen-Tian Sun Xin-Qi Huang Jing-yu Chi ling-Jie Wang Zhi-He Zhao Jun liu State Key Laboratory of Oral Diseases&National Clinical Research Center for Oral Diseases Department of OrthodonticsWest China Hospital of StomatologySichuan UniversityChengdu 610041Sichuan ProvinceChina Department of Stomatology Strategic Support Force Medical Center of PLABeijing 10010China Department of Stomatology Qingyang People's HospitalQingyang 745000Gansu ProvinceChina

BACKGROUND The role of occlusal factors on the occurrence of temporomandibular joint disorders(TMDs)is still unclear and it is tricky for orthodontists to treat malocclusions in patients with *** report the case of the second orthodontic treatment of an adult female with Class II division 2 malocclusion associated with *** the removal of anterior occlusal interference,TMD symptoms were alleviated and cone beam computed tomography(CBCT)images showed the bilateral condyles shifted *** SUMMARY This case report presented an orthodontic retreatment of an adult female with TMD and mandibular backward positioning based on CBCT examination and Joint Space Index(JSI)*** left and right JSI values of-38.5 and-52.6 indicated that the position of bilateral condyles had posterior *** years prior to this evaluation,she underwent orthodontic treatment resulting in the extraction of two upper premolars and one lower central *** joint symptoms,including pain and sounds,were alleviated along with verified mandibular forward repositioning by extraction of another lower central *** Mandibular backward positioning could be associated with *** analysis based on CBCT is a convenient way to examine condylar positions quantitatively.

关键词： Cone beam computerized tomography Joint Space Index Temporomandibular joint disorder Case report

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Synthesis, Characterization and Antitumor Activities of Co, Ni, Cu, Zn Complexes with 1,4,7,10-tetrakis(4-nitrobenzyl)-1,4,7,10 tetraazacyclododecane Macrocyclic ligand

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Chinese Journal of Structural Chemistry 2000年第1期19卷 39-47页

作者： KONG De\|yuan a* \ XIE yu\|li a\ XIE yu\|yuan a\ HUANG Xiao\|Ying ba (Shanghai Institute of Materia Medica, the Chinese Academy of Sciences, Taiyuan Road 294, Shanghai, 200031, P. R. China) b (Department of Chemistry, Rugters University, New Jer 中科院上海药物所上海 2 0 0 0 31 Rugters University 美国 New Jersey 08102

New tetraazamacrocyclic ligand with 1,4,7,10 tetrakis(4 nitrobenzyl) pendent groups (C 36 H 40 N 8O 8, M r =712.76) crystallized in the monoclinic system, P2 1/n space group with unit cell parameters: a=7.834(2), b=22.902(6), c=10\^147(3), β=106.53(2)°, V=1745(1) 3, Z=2, D c =1.356 g/cm 3, λ (Mo Kα )=0.71069; μ =0.92cm -1 , F(000)=752, T =296K. The final R and R w values are 0\^065 and 0.066, respectively. The Cu(Ⅱ), Ni(Ⅱ), Co(Ⅱ), Zn(Ⅱ) complexes with this new ligand have been synthesized and characterized by elemental analyses, IR, UV, ESI MS and molar conductance. The macrocyclic ligand molecular structure is centrosymmetrical. All complexes are in accordance with the general formula: M(L)(NO 3) 2·nH 2O (M=Co, Ni, Cu, n=2; M=Zn, n=4; L=C 36 H 40 \|N 8O 8). The central metal ions coordinate to four nitrogen atoms of azamacrocycle and two oxygen atoms of one nitrate ion. Preliminary pharmacological tests against P 388 and A 549 tumor cell lines showed that all these complexes had considerable activities in vitro.

关键词： synthesis macrocyclic ligand antitumor activity crystal structure

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