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光学学报 1988年第11期 1038-1043页

作者：连波金国藩清华大学微细工程研究所清华大学微细工程研究所华中光电技术研究所

本文在一维布喇格衍射分析方法的基础上,导出了两维时的衍射场光能量分布,给出了相应的实验结果.分析了影响衍射光光斑能量分布的主要因素,最后提出了综合考虑衍射效率,上升时间、光斑形状的新的设计思想.

关键词：布喇格衍射光斑形状

Pesticide-induced photoluminescence quenching of ultra-small Eu3+-activated phosphate and vanadate nanoparticles

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Journal of Materials Science & Technology 2020年第3期38卷 197-204页

作者： Jovana Perisa Zeljka Antic Chong-Geng Ma Jelena Papan dragana Jovanovic Miroslav d.dramicanin Vinca Institute of Nuclear Sciences University of BelgradeP.O.Box 52211001 BelgradeSerbia College of Sciences Chongqing University of Posts and TelecommunicationsChongqing 400065China

The aim of this research was to investigate the luminescent behavior of ultra-small Eu3+-activated phosphate and vanadate nanoparticles in the presence of *** have an average diameter of approximately 2 nm with a narrow size *** monazite crystal structure of phosphate-based particles(space group P121/n1)and single tetragonal zircon-type structure of vanadate-based particles(space group of I41/amd)have been confirmed using X-ray diffraction *** synthesized Eu3+-activated colloidal nanoparticles show sharp emission peaks in the red spectral *** measurements revealed emission quenching upon addition of millimolar concentrations of following pesticides:4-Chloro-2-methyl-phenoxyacetic acid(MCPA),2,4-dichlorophenoxyacetic acid(2,4-d)and N-(phosphonomethyl)glycine(Glyphosate).In both phosphate and vanadate-based colloidal nanoparticles luminescence quenching is more evident in the presence of 2,4-d pesticide with the lowest limit of detection(0.7μM)obtained for phosphate-based nanoparticles.

关键词： Phosphate/vanadate based colloidal nanoparticles Eu3+ Emission quenching Pesticide

NOTE ON PHYSIOGRAPHY OF NORTHERN SZECHUAN ANd SOUTHERN KANSU

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地理学报 1942年 103-111页

作者： M.N.JEN Ph.d. National Chekiang University National Chekiang University Prof

The Present paper is an outcome of a trip to Northern Szechuan and Southern Kansu in July-October, 1941. Briefly speaking, the region under consideration is limited by Lanehow on thc north, Nuikiang on the south and ... 详细信息

关键词： In NOTE ON PHYSIOGRAPHY OF NORTHERN SZECHUAN ANd SOUTHERN KANSU

New Technologies on Mine Process Tailing disposal

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Journal of Geological Resource and Engineering 2016年第2期4卷 63-72页

作者： Bascetin A Tuylu S Adlguzel d Ozdemir O Mining Engineering departrnent Engineering Faculty Istanbul University Istanbu134413 Turkey

Tailings are formed as a result of mine processing. When these tailings are left in an environment in an inappropriate manner, they create a danger against the environment and human health. Therefore, the safe disposal of mine tailings above the ground is environmentally quite important. Today, tailing dams are generally used in the disposal of these mine tailings. However, this method has many environmental disadvantages such as amd （acid mine drainage）, heavy metal mobilization etc. For this reason, the use of alternative methods such as surface paste tailing disposal or geotextile methods are gradually increasing in the world. In this study, the advantages and disadvantages of the surface paste tailing disposal method and tailing disposal method using geotextile material compared to the traditional tailing dam method were evaluated in detail, and, the costs of these three methods for a typical Pb-Zn mine establishment were compared. The analysis indicated that the unit costs of the tailing dam, the surface disposal method, and the geotextile method were calculated as 2.25 S/ton, 2.29 S/ton, and 7.39 S/ton, respectively. However, the unit price of surface paste disposal method become 2.79 S/ton when cement was used. The higher cost of the unit price of the tailing disposal method using geotextile method was attributed to the high cost of geotextile material.

关键词： Mine tailing tailing dam surface paste disposal geotextile material.

Fitting and evaluation of height-diameter models for Alnus japonica in La Trinidad, Benguet, Philippines

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Journal of Mountain Science 2018年第11期15卷 2422-2432页

作者： Kamae P.ANACIOCO Judy Ann L.GORIO Mary Relia S.PAdSICO Roscinto Ian C.LUMBRES Nova d.dOYOG Young Jin LEE College of Forestry Benguet State University department of Forest Resources College of Industrial Science Kongju National University

The study was conducted to develop height-diameter at breast height(HT-dBH) models for Alnus japonica in La Trinidad, Benguet,Philippines and evaluate their predictive *** six widely used nonlinear growth models that were selected in this study were the ChapmanRichards, Schnute, Modified logistic, Korf/Lundqvist,Weibull and Exponential. A total of 208 Alnus japonica trees were measured using standard diameter tape for dBH(1.3 m above the ground) and Vertex and transponder was used for the total height measurement. The performance of the developed models were evaluated using the fit statistics including coefficient of determination(R^2), root mean square error(RMSE), mean bias(ē), absolute mean difference(amd), and Akaike Information Criterion(AIC). The lack-of-fit statistics was also performed for further evaluation of the performance of the *** on the evaluation criteria, all six models were able to determine the dBH-height relationships and fitted the data well. Using the rank analysis, the Weibull HT-dBH model had the best performance among the six commonly used nonlinear growth models. The results of this study will help forest managers especially in La Trinidad, Benguet to easily predict the total height using the Weibull model for Alnus japonica utilizing the dBH as the predicting variable.

关键词： Height- dBH model Alnus japonica Rank analysis La Trinidad Benguet Philippines

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作物秸秆碳在土壤中分解和转化规律的研究

植物营养与肥料学报 1994年第1期 27-28页

作者：张夫道 FokinA.d. 中国农科院土壤肥料研究所莫斯科季夫里亚捷夫农学院

采用^(14)C—标记秸秆,在大田和实验室的研究结果表明,秸秆的分解速率主要取决于C/N比。施入土壤后,土壤微生物迅速增加,尤其是细菌。秸秆降解首先形成非结构物质,其中大部分转化为富里酸,进而转化为胡敏酸。分解产物对土壤腐殖质的更新... 详细信息

采用^(14)C—标记秸秆,在大田和实验室的研究结果表明,秸秆的分解速率主要取决于C/N比。施入土壤后,土壤微生物迅速增加,尤其是细菌。秸秆降解首先形成非结构物质,其中大部分转化为富里酸,进而转化为胡敏酸。分解产物对土壤腐殖质的更新,从腐殖质表面官能团或分子断片开始,逐步进行。非结构物质可与腐殖酸的单个分子产生交联作用,在一定条件下,交联的复合分子可进入腐殖质分子核心的成分中。腐殖酸单个组分在土壤中的转化和重新分配,仅仅与腐殖质表面官能团的反交换过程密切相关。粘土矿物选择性吸附胡敏酸,而且优先吸附胡敏酸中低分子成分。

关键词：秸秆分解转化腐殖质

Big dNA as a tool to dissect an age-related macular degeneration-associated haplotype

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Precision Clinical Medicine 2019年第1期2卷 1-7页

作者： Jon M.Laurent Xin Fu Sergei German Matthew T.Maurano Kang Zhang Jef d.Boeke Institute for Systems Genetics department of Biochemistry and Molecular Pathology department of Pathology NYU Langone Health Shiley Eye Institute UCSD School of Medicine

Age-related Macular degeneration(amd)is a leading cause of blindness in the developed world,especially in aging populations,and is therefore an important target for new therapeutic ***,there have been several studies demonstrating strong associations between amd and sites of heritable genetic variation at multiple loci,including a highly significant association at *** 10q26 risk region contains two genes,HTRA1 and ARMS2,both of which have been separately implicated as causative for the disease,as well as dozens of sites of non-coding *** date,no studies have successfully pinpointed which of these variant sites are functional in amd,nor definitively identified which genes in the region are targets of such regulatory *** order to efficiently decipher which sites are functional in amd phenotypes,we describe a general framework for combinatorial assembly of large‘synthetic haplotypes’along with delivery to relevant disease cell types for downstream functional *** demonstrate the successful and highly efficient assembly of a first-draft 119kb wild-type‘assemblon’covering the HTRA1/ARMS2 risk *** further propose the parallelized assembly of a library of combinatorial variant synthetic haplotypes covering the region,delivery and analysis of which will identify functional sites and their effects,leading to an improved understanding of amd *** anticipate that the methodology proposed here is highly generalizable towards the difficult problem of identifying truly functional variants from those discovered via GWAS or other genetic association studies.

关键词： CRISPR gene editing synthetic biology age related macular degeneration HTRA1

Beneficial effects of saffron(Crocus sativus L.) in ocular pathologies, particularly neurodegenerative retinal diseases

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Neural Regeneration Research 2020年第8期15卷 1408-1416页

作者： Jose A.Fernandez-Albarral Rosa de Hoz Ana I.Ramirez Ines Lopez-Cuenca Elena Salobrar-Garcia Maria d.Pinazo-duran Jose M.Ramirez Juan J.Salazar Instituto de Investigaciones Oftalmologicas Ramon Castroviejo MadridSpain departamento de Inmunologia Oftalmologia y ORLFacultad de Optica y OptometriaMadridSpain departamento de Inmunologia Oftalmologia y ORLFacultad de MedicinaMadridSpain Unidad de Investigacion Oftalmologica Santiago Grisolia Universidad de ValenciaValenciaSpain

Saffron(Crocus sativus L.)has been traditionally used in food preparation and as a medicinal *** currently has numerous therapeutic properties attributed to it,such as protection against ischemia,as well as anticonvulsant,antidepressant,anxiolytic,hypolipidemic,anti-atherogenic,anti-hypertensive,antidiabetic,and anti-cancer *** addition,saffron has remarkable beneficial properties,such as anti-apoptotic,anti-inflammatory and antioxidant activities,due to its main metabolites,among which crocin and crocetin stand ***,increasing evidence underwrites the possible neuroprotective role of the main bioactive saffron constituents in neurodegenerative diseases,such as Parkinson’s and Alzheimer’s diseases,both in experimental models and in clinical studies in ***,saffron supplementation is being tested for ocular neurodegenerative pathologies,such as diabetic retinopathy,retinitis pigmentosa,age-related macular degeneration and glaucoma,among others,and shows beneficial *** present article provides a comprehensive and up to date report of the investigations on the beneficial effects of saffron extracts on the main neurodegenerative ocular pathologies and other ocular *** review showed that saffron extracts could be considered promising therapeutic agents to help in the treatment of ocular neurodegenerative diseases.

关键词： amd crocetin crocin Crocus sativus L. diabetic retinopathy glaucoma neuroprotection ocular diseases retinitis pigmentosa saffron safranal

End-stage renal disease is associated with increased post endoscopic retrograde cholangiopancreatography adverse events in hospitalized patients

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World Journal of Gastroenterology 2018年第41期24卷 4691-4697页

作者： Tarek Sawas Fateh Bazerbachi Samir Haffar Won K Cho Michael J Levy John A Martin Bret T Petersen Mark d Topazian Vinay Chandrasekhara Barham K Abu dayyeh division of Gastroenterology and Hepatology Mayo Clinic department of Gastroenterology Digestive Center for Diagnosis and Treatment division of Gastroenterology and Hepatology Georgetown University Medstar Washington Hospital Center

AIM To determine if end-stage renal disease (ESRd) is a risk factor for post endoscopic retrograde cholangio-pancreatography (ERCP) adverse events (AEs). METHOdS We performed a retrospective cohort study using the Nationwide Inpatient Sample (NIS) 2011-2013. We identified adult patients who underwent ERCP using the International Classification of diseases 9^(th) Revision (ICd-9-CM). Included patients were divided into three groups: ESRd, chronic kidney disease (CKd), and control. The primary outcome was post-ERCP AEs including pancreatitis, bleeding, and perforation determined based on specific ICd-9-CM codes. Secondary outcomes were length of hospital stay, in-hospital mortality, and admission cost. AEs and mortality were compared using multivariate logistic regression *** There were 492175 discharges that underwent ERCP during the 3 years. The ESRd and CKd groups contained 7347 and 39403 hospitalizations respectively, whereas the control group had 445424 hospitalizations. Post-ERCP pancreatitis (PEP) was significantly higher in the ESRd group (8.3%) compared to the control group (4.6%) with adjusted odd ratio (aOR) = 1.7 (95% CI: 1.4-2.1, ~aP d was associated with significantly higher ERCP-related bleeding (5.1%) compared to the control group 1.5% (aOR = 1.86, 95%CI: 1.4-2.4, ~aP d had increased hospital mortality 7.1% vs 1.15% in the control OR = 6.6 (95%CI: 5.3-8.2, ~aP djusted mean difference (amd) = 5.9 d (95% CI: 5.0-6.7 d, ~aP d higher hospitalization charges amd = $+82064 (95%CI: $68221-$95906, ~aP d is a risk factor for post-ERCP AEs and is associated with higher hospital mortality. Careful selection and close monitoring is warranted to improve outcomes.

关键词： End-stage renal disease Nationwide Inpatient Sample Endoscopic retrograde cholangiopancreatography

Unfolded annealing molecular dynamics conformers for wild-type and disease-associated variants of alpha-synuclein show no propensity for beta-sheetformation

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Journal of Biophysical Chemistry 2011年第2期2卷 124-134页

作者： d. Balesh Z. Ramjan W.B. Floriano Biological Sciences department California State Polytechnic University Pomona Pomona CA 91768 department of Chemistry at Lakehead University and Thunder Bay Regional Research Institute Thunder Bay ON Canada P7B 5E1

Aggregation of alpha-synuclein leads to the formation of Lewy bodies in the brains of patients affected by Parkinson's disease (Pd). Native human alpha-synuclein is unfolded in solution but assumes a partial alpha-helical conformation upon transient binding to lipid membranes. Annealing Molecular dynamics (amd) was used to generate a diverse set of unfolded conformers of free monomeric wild-type alpha-synuclein and Pd-associated mutants A30P and A53T. The amd conformers were compared in terms of secondary structure, hydrogen bond network, solvent-accessible surface per residue, and molecular volume. The objective of these simulations was to identify structural properties near mutation sites and the non-amyloid component (NAC) region that differ between wild- type and disease-associated variants and may be associated to aggregation of alpha- synuclein. Based on experimental evidence, a hypothesis exists that aggregation involves the formation of intermolecular beta sheets. According to our results, disease-associated mutants of alpha-synuclein are no more propense to contain extended beta regions than wild-type alpha-synuclein. Moreover, extended beta structures (necessary for beta sheet formation) were not found at or around positions 30 and 53, or the NAC region in any unfolded conformer of wild-type, A30P or A53T alpha-synuclein, under the conditions of the simulations. These results do not support the hypothesis that the mutant's higher propensity to aggregation results solely from changes in amino acid sequence leading to changes in secondary structure folding propensity.

关键词： Alpha-Synuclein Parkinson's disease Lewy Body Formation Beta Sheet Formation Unfolding Molecular Simulations