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Nanostructured Al-Zn-Mg-Cu alloy synthesized by cryomilling and spark plasma sintering

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中国有色金属学会会刊：英文版 2009年第5期19卷 1110-1115页

作者：陈汉宾陶凯杨滨张济山 No.59 Institute of China Ordnance Industry State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing

Nanocrystallized Al-10.0%Zn-3.0%Mg-1.8%Cu(mass fraction)alloy powder was prepared by cryomilling,and then the nanostructured powder was consolidated into bulk material by spark plasma sintering(SPS).The microstructural evolution and phase transformation were studied.A supersaturated face-centered cubic solid solution is formed after cryomilling for 10 h,and the average grain size is 28 *** typical nanostructures of the bulk nanostructured alloy are observed:primarily equiaxed grains with size of 150 nm,and occasionally occurring sub-micron grains up to 500 *** types of MgZn2 particles precipitate during consolidation. One is the sub-micron particles distributed along the boundaries of the powders,and the other is fine particles with size of several nanometers in the matrix,especially at the boundaries of sub-micron *** second phase particles can be completely dissolved into matrix by proper solid solution treatment.

关键词：放电等离子烧结铜合金亚微米颗粒亚微米粒子合成纳米粉体材料镁锌

Inhomogeneity of microstructure and mechanical properties of a 500 mm diameter heavy section semi-continuous cast AZ61 magnesium alloy ingot

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China Foundry 2014年第1期11卷 33-38页

作者： Peng Jian Tao Jianquan Tong Xiaoshan Pan Fusheng College of Materials Science and Engineering Chongqing University No. 59 Institute of China Ordnance Industry

For the large magnesium alloy ingot, there is a considerable difference in cooling rate of different parts in the ingot, which leads to non-uniform distribution of the secondary phases, solute segregation and tensile properties. In the present research, an heavy AZ61 alloy ingot with a diameter of 500 mm was made by semi-continuous casting. The microstructure and mechanical properties at different positions along the radial direction of the large ingot were investigated by using an optical microscope(OM), a scanning electron microscope(SEM), an energy dispersive spectroscope(EDS), and a micro-hardness tester. The results indicate that the microstructure of the AZ61 ingot is non-uniform in different locations. It changes from equiaxed to columnar grains from the center to the edge; the average grain size gradually reduces from 1,005 μm to 763 μm, the secondary dendrite arm spacing reduces from 78 μm to 50 μm, and the Mg17(Al,Zn)12 phase is also refined. The micro-hardness value increases from 55.4 HV at the center to 72.5 HV at the edge of the ingot due to the microstructure differences, and the distribution of micro-hardness at the edge of the ingot is more uniform than that in the center. The tensile properties at room temperature show little difference from the center to the edge of the ingot except that the elongation at the edge is only 3.5%, much lower than that at other areas. The fracture mechanism is ductile fracture at the center and cleavage fracture at the edge of the ingot, and at the 1/2 radius of the ingot, a mixture of ductile and cleavage fracture is present.

关键词： AZ61 magnesium alloy semi-continuous casting microstructure properties

Defining the Functional Network of Epigenetic Regulators in Arabidopsis thaliana

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Molecular Plant 2009年第4期2卷 661-674页

作者： Chongyuan Luo Brittany G. Durgin Naohide Watanabe Eric Lain Biotechnology Center for Agriculture and the Environment Rutgers The State University of New Jersey 59 Dudley Road New Brunswick NJ 08901 USA Department of Plant Biology and Pathology Rutgers The State University of New Jersey 59 Dudley Road New Brunswick NJ 08901 USA

Development of ChiP-chip and ChlP-seq technologies has allowed genome-wide high-resolution profiling of chromatin-associated marks and binding sites for epigenetic regulators. However, signals for directing epigenetic modifiers to their target sites are not understood. In this paper, we tested the hypothesis that genome location can affect the involvement of epigenetic regulators using Chromatin Charting （CC） Lines, which have an identical transgene construct inserted at different locations in the Arabidopsis genome. Four CC lines that showed evidence for epigenetic silencing of the luciferase reporter gene were transformed with RNAi vectors individually targeting epigenetic regulators LHP1, MOM1, CMT3, DRD1, DRM2, SUVH2, CLF, and HD1. Involvement of a particular epigenetic regulator in silencing the transgene locus in a CC line was determined by significant alterations in luciferase expression after suppression of the regulator＇s expression. Our results suggest that the targeting of epigenetic regulators can be influenced by genome location as well as sequence context. In addition, the relative importance of an epigenetic regulator can be influenced by tissue identity. We also report a novel approach to predict interactions between epigenetic regulators through clustering analysis of the regulators using alterations in gene expression of putative downstream targets, including endogenous loci and transgenes, in epigenetic mutants or RNAi lines. Our data support the existence of a complex and dynamic network of epigenetic regulators that serves to coordinate and control global gene expression in higher plants.

关键词： Cell differentiation specialization chromatin structure and remodeling chromosome organization epigenetics aene silencina Arabidopsis.

Is Tetranychus urticae suitable prey for development and reproduction of nafve Coleomegilla maculata？

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Insect Science 2014年第1期21卷 83-92页

作者： Eric W. Riddick Zhixin Wu M~ Guadalupe Rojas National Biological Control Laboratory Agricultural Research Service USDA 59 Lee Road Stoneville MS 38776 USA

The lady beetle Coleomegilla maculata De Geer is an omnivorous predator that could help suppress aphid and spider mite populations on plants in greenhouses, plantscapes or interiorscapes. We are assessing the nutritional requirements and feeding behavior of C. maculata on target prey （spider mites） and factitious （unnatural） food. Our ultimate goal is to develop an efficacious diet to mass produce C. maculata. In this study, we tested the hypothesis that Tetranychus urticae Koch （two-spotted spider mite） is not suitable prey for development and reproduction of naive C. maculata （i.e., with no prior exposure to T. urticae）. Our objectives were to （i） provide baseline data on the effects of consuming T. urticae on C. maculata life history, （ii） to compare the effects of consuming all stages of T. urticae versus eggs ofMusca domestica L. （common housefly）, and （iii） to determine if the consumption of plant products was beneficial. We used C. maculata from a colony reared only on Ephestia kuehniella Zeller （Mediterranean flour moth） eggs. In experiments, C. maculata larvae were reared from the first instar to adult stage with prey/food in replicated arenas; adult females were paired with a single male with prey/food. The results showed that naive C. maculata readily attacked and consumed T. urticae. Nevertheless, T. urticae was less suitable than M. domestica eggs for C. maculata development and reproduction. Applying a synthetic pollen-Chlorella alga powder （SPCA） in arenas containing T. urticae appeared to boost C. maculata female development and reproduction.

关键词： behavior biocontrol CoccineUidae nutrition rearing

Taxonomic placement of Epichloëpoae *** horizontal dissemination to seedlings via conidia

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Fungal Diversity 2012年第3期54卷 117-131页

作者： Mariusz Tadych Karen V.Ambrose Marshall S.Bergen Faith C.Belanger James F.White Jr Department of Plant Biology and Pathology Rutgers University59 Dudley RoadNew BrunswickNJ 08901USA

A new Epichloëspecies distributed in Africa,Europe,North America and South America on host genera Bromus,Festuca,Lolium and Poa is ***,characteristic of the genus,frequently occurred on the reproductive tillers of Poa secunda ***,but neither perithecia nor mature asci were *** cells and conidial characteristics were in the range of Epichloë*** of the genes encodingβ-tubulin(tub2)and translation elongation factor 1-α(tef1)were amplified and *** analyses of these sequences grouped the Poa secunda *** endophyte into one group within a non-hybrid Epichloëspecies *** the basis of morphology,host range and evolutionary history we propose that this endophyte represents a new species of Epichloë.The name Epichloëpoae is proposed for this *** infectivity of the conidia produced on plants was *** the first experiment,using conidia of Epichloëpoae from leaves and endophytefree seeds of Poa secunda *** we show that when germinating seeds and developing seedlings of the plant were exposed to conidia,28–57%of seedlings became infected by the *** non-inoculated control plants showed no colonization by the *** the following spring after vernalization,colonized plants on flowering culms produced stromata with *** the second experiment,using stromal conidia and the same procedure,19–42%of seedlings of Poa secunda *** became colonized by the *** results demonstrate that Epichloëpoae may spread to uninfected grass hosts by conidia frequently formed on the surfaces of plant leaves as well as by conidia formed on stromata.

关键词： Endophyte Epiphyllous Evolution Neotyphodium Poa secunda subsp juncifolia Seed

Expression of annexin II in gastric carcinoma and its role in gastric cancer metastasis

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World Journal of Gastroenterology 2017年第38期23卷 7009-7015页

作者： Feng Han Shikha Shrestha Hua Huang Huang-Yong Lv Chuan Nie Ling Lin Ming-Liang Lu Department of Gastroenterology the PLA No.59 Hospital Department of Gastroenterology The Second Affiliated Hospital Kunming Medical University

AIM To investigate the expression of annexin II in gastric carcinoma and its role in the metastasis of gastric *** The expression of annexin II in 51 cases of gastric carcinoma and 24 cases of adjacent tissues was detected by immunohistochemistry. The relationship between annexin II and clinical features of gastric cancer was analyzed. Annexin II specific si RNA was used to inhibit the expression of annexin II in gastric cancer HGC-27 cells, and the effects of annexin II on the migration and secretion of matrix metalloproteinases(MMPs) were *** The positive rate of annexin II protein was 82.4% in gastric cancer tissues and 37.5% in adjacent tissues. There was significant difference between the two groups(P 0.05). The expression of annexin IIprotein was correlated with tumor size, histological differentiation, TNM stage, Lymph node metastasis and other clinical features were significantly correlated, the difference was statistically significant(P < 0.05). Inhibition of annexin II expression, gastric cancer HGC-27 cells migration and secretion of MMPs were significantly decreased, the difference was statistically significant(P < 0.05).CONCLUSION Annexin II is highly expressed in gastric cancer tissues, annexin II protein expression is related to tumor size, histological differentiation, TNM staging, lymph node metastasis and other clinical features were significantly correlated. Annexin II high expression can promote the invasion and metastasis of gastric cancer.

关键词： Gastric cancer Annexin II Metastasis Realtime quantitative PCR Human gastric cancer HGC-27 cells Matrix metalloproteinases

Prediction and datamining of burned areas of forest fires:Optimized data matching and mining algorithm provides valuable insight

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Artificial Intelligence in Agriculture 2021年第1期5卷 24-42页

作者： David A.Wood DWA Energy Limited 25 Badgers OakBassinghamLincoln LN59JPUnited Kingdom

An optimized data-matching machine learning algorithm is developed to provide high-prediction accuracy of total burned areas for specific wildfire *** is applied to a well-studied forest-fire dataset from Portugal Montesinho Natural Park considering 13 input *** total burned area distribution of the 517 burn events in that dataset is highly positively *** model is transparent and avoids regressions and hidden *** increases its detailed datamining *** matches the highest burned-area prediction accuracy achieved for this datasetwith a wide range of traditionalmachine learning *** two-stage prediction process provides informative feature selection that establishes the relative influences of the input variables on burned-area *** with mean absolute error(MAE)and root mean square error(RMSE)as separate objective functions provides complementary information with which to data mine each total burnedarea *** insight offers potential agricultural,ecological,environmental and forestry benefits by improving the understanding of the key influences associated with each burn *** mining the differential trends of cumulative absolute error and squared error also provides detailed insight with which to determine the suitability of each optimized solution to accurately predict burned-areas events of specific *** prediction accuracy and insight leads to confidence in how each prediction is *** provides knowledge to make appropriate responses and mitigate specific burn incidents,as they *** informed responses should lead to short-term and long-term multi-faceted benefits by helping to prevent certain types of burn incidents being repeated or spread.

关键词： Wildfire feature selection Non-regression machine learning Data-matched prediction accuracy Cumulative absolute error differentials Predicting highly skewed distributions

Conditional gene expression in invertebrate animal models

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Journal of Genetics and Genomics 2021年第1期48卷 14-31页

作者： Brecht Driesschaert Lucas Mergan Liesbet Temmerman Animal Physiology and Neurobiology Department of BiologyUniversity of Leuven(KU Leuven)Naamsestraat 59-Box 2465B-3000 LeuvenBelgium

A mechanistic understanding of biology requires appreciating spatiotemporal aspects of gene expression and its functional *** expression allows for (ir)reversible switching of genes on or off,with the potential of spatial and/or temporal *** provides a valuable complement to the more often used constitutive gene (in)activation through mutagenesis,providing tools to answer a wider array of research questions across biological *** and/or temporal control are granted primarily by(combinations of) specific promoters,temperature regimens,compound addition,or *** use of such genetic tool kits is particularly widespread in invertebrate animal models because they can be applied to study biological processes in short time frames and on large scales,using organisms amenable to easy genetic *** years witnessed an exciting expansion and optimization of such tools,of which we provide a comprehensive overview and discussion regarding their use in *** mechanism,applicability,benefits,and drawbacks of each of the systems,as well as further developments to be expected in the foreseeable future,are highlighted.

关键词： Conditional gene expression Spatiotemporal control Invertebrate Model organism Drosophila melanogaster Caenorhabditis elegans

Hydatid cyst/cystic echinococcosis： anatomical and surgical nomenclature and method to quantify the cyst content solidification

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Chinese Medical Journal 2011年第18期124卷 2806-2812页

作者： A. Menezes da Silva General Surgery Pulido Valente Hospital Lisbon Estrada da Luz 59-8° Dto.1600-152-Lisboa Portugal

The terminology related to the hydatid cyst is sometimes inappropriate and wrong designations are used, based on incorrect concepts. ＂Hydatid cyst＂ is the larval form of the tapeworms of the genus Echinococcus granulosus, a parasite found in the small intestine of carnivores. The disease, called cystic echinococcosis, As among the most neglected parasitic diseases despite the development of new drugs and other treatment modalities. Although all of us know the vital cycle of the parasite and the different aspects of the disease, the designations around the parasite, its evolution and some therapeutic procedures are not uniform. It would be useful, for all of us, to use the same nomenclature and it is absolutely necessary that the nomenclature As correct and universally accepted. In this paper I remember the correct terms related to all aspects of the hydatid cyst＇s nomenclature, including especially the anatomical and surgical terminology, as well as the criteria to define the cyst inactivity and the way to know when the cyst range the inactive stage after therapy.

关键词： hydatid cyst hydatid layers hydatidectomy cystectomy cyst inactivity cyst solidification