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High pressure luminescence studies of europium doped GaN

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Journal of Rare Earths 2009年第4期27卷 667-670页

作者： K.Wisniewski W.Jadwisieńczak T.Thomas m.Spencer Institute of of Experimental Physics Gdańsk University ul.Wita Stwosza 57 Gdańsk 80-952 Poland School of Electrical Engineering and Computer Science Ohio-University Athens OH 45701 USA Second of Electrical and Computer Engineering Cornell University Ithaca NY 14853 USA

We reported on the high pressure luminescence spectra of polycrystalline Eu-doped GaN material synthesized in the reaction between alloys of gallium, bismuth and europium in ammonia atmosphere. The integrated luminescence intensity of the dominant Eu3＋ ion transition （5D0→^7F2） at 622 nm increased approximately one order of rnagnitude whereas its spectral position and line width did not change significantly between ambient and 6.8 GPa pressure, respectively. moreover, material was characterized with photo- and cathodo-luminescence, and photoluminescence excitation spectra at different temperatures. It was found that the Eu3＋ ions occupying substitutional Ga site created different centers which could be effectively excited with above band gap excitation and from excitons resonantly photoexcited at the I2 bound exciton energy. Furthermore, the less efficient Eu3＋ ions excitation path existed through intrinsic impurities and defeels generating shallow energy levels in the forbidden gap. It was proposed that reduction of the thermal quenching and consequent enhancement of Eu3＋ ion emission intensity resulted from stronger localization of bound exciton on RESI trap induced by applied pressure.

关键词： GaN, Eu^3+ ion high pressure spectroscopy rate earths

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Delineation of homogeneous forest patches using combination of field measurements and LiDAR point clouds as a reliable reference for evaluation of low resolution global satellite data

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Forest Ecosystems 2018年第1期5卷 1-12页

作者： krzysztof stereńczak marek lisańczuk yousef erfanifard department of forest resources management forest research instituteSekocin Stary 3 Braci Lesnej，05-090 Raszyn，Poland department ofnatural resources and environment college of agriculture shiraz universityp.o.box ***shiraziran

Backgrounds： There are many satellite systems acquiring environmental data on the world. Acquired global remote sensing datasets require ground reference data in order to calibrate them and assess their quality. Regarding calibration and validation of these datasets with broad geographical extents, it is essential to register zones which might be considered as Homogeneous Patches （HPs）. Such patches enable an optimal calibration of satellite data/sensors, and what is more important is an analysis of components which significantly influence electro-magnetic signals registered by satellite sensors. methods： We proposed two structurally different methods to identify HPs： predefined thresholding-based one （static one）, and statistical thresholding-based technique （dynamic one）. In the first method, 3 different thresholds were used： 5%, 10%, and 20%. Next, it was aimed to assess how delineated HPs were spatially matched to satellite data with coarse spatial resolution. Selected cell sizes were 25, 50, 100, 250, and 500 m. The number of particular grid cells which almost entirely fell into registered HPs was counted （leaving 2% cell area tolerance level）. This procedure was executed separately for each variant and selected structural variables, as well as for their intersection parts. Results： The results of this investigation revealed that ALS data might have the potential in the identification of HPs of forest stands. We showed that different ALS based variables and thresholds of HPs definition influenced areas which can be treated as similar and homogeneous. We proved that integration of more than one structural variable limits size of the HPs, in contrast, visual interpretation revealed that inside such patches vegetation structure is more constant. Conclusions： We concluded that ALS data can be used as a potential source of data to ＂enlarge＂ small ground sample plots and to be used for evaluation and calibration of remotely sensed datasets provided by global systems

关键词： Forest structure Stratification Global satellite missions

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The Story of the Century

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英语学习 1995年第8期 34-35页

作者： m.rta Tikkanen

玛尔塔·蒂坎恩是芬兰本世纪七十至八十年代女权主义运动中著名作家和诗人。她的散文诗《本世纪的故事》严肃地反映了妇女婚姻家庭矛盾,诗中那位妇女发出"Love me less,respect me more"的心声,不难读出作者及那个时代的芬兰女性已渐鲜... 详细信息

玛尔塔·蒂坎恩是芬兰本世纪七十至八十年代女权主义运动中著名作家和诗人。她的散文诗《本世纪的故事》严肃地反映了妇女婚姻家庭矛盾,诗中那位妇女发出"Love me less,respect me more"的心声,不难读出作者及那个时代的芬兰女性已渐鲜明的自我意识。

关键词：女权主义家庭矛盾散文诗 The Story of the Century 玛尔塔自我意识

Glucagon-like peptide 1 in the pathophysiology and pharmacotherapy of clinical obesity

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World Journal of Diabetes 2016年第20期7卷 572-598页

作者： Ananthi Anandhakrishnan m.rta Korbonits Centre for Endocrinology William Harvey Research InstituteBarts and the London School of Medicine and DentistryQueen Mary University of London

Though the pathophysiology of clinical obesity is un-doubtedly multifaceted, several lines of clinical evidence implicate an important functional role for glucagon-like peptide 1(GLP-1) signalling. Clinical studies assessing GLP-1 responses in normal weight and obese subjects suggest that weight gain may induce functional deficits in GLP-1 signalling that facilitates maintenance of the obesity phenotype. In addition, genetic studies implicate a possible role for altered GLP-1 signalling as a risk factor towards the development of obesity. As reductions in functional GLP-1 signalling seem to play a role in clinical obesity, the pharmacological replenishment seems a promising target for the medical management of obesity in clinical practice. GLP-1 analogue liraglutide at a high dose(3 mg/d) has shown promising results in achieving and maintaining greater weight loss in obese individuals compared to placebo control, and currently licensed antiobesity medications. Generally well tolerated, provided that longer-term data in clinical practice supports the currently available evidence of superior short- and longterm weight loss efficacy, GLP-1 analogues provide promise towards achieving the successful, sustainable medical management of obesity that remains as yet, an unmet clinical need.

关键词： Obesity pathophysiology Glucagon-like peptide 1 analogues Glucagon-like peptide 1 Clinical obesity

New serological markers in pediatric patients with inflammatory bowel disease

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World Journal of Gastroenterology 2014年第17期20卷 4873-4882页

作者： m.rta Kovács Katalin Eszter müller mária Papp Péter László Lakatos mihály Cs?ndes Gábor Veres Department of Pediatrics Petz Aladár County and Teaching Hospital9023 Gy?rHungary 1~(st) Department of Pediatrics Semmelweis University1083 BudapestHungary 2~(nd) Department of medicine University of Debrecen4032 DebrecenHungary 1~(st) Department of medicine Semmelweis University1083 BudapestHungary Department of Gastroenterology Petz Aladár County and Teaching Hospital9023 Gy?rHungary

The spectrum of serological markers associated with inflammatory bowel disease (IBD) is rapidly growing. Due to frequently delayed or missed diagnoses, the application of non-invasive diagnostic tests for IBD, as well as differentiation between ulcerative colitis (UC) and Crohn’s disease (CD), would be useful in the pediatric population. In addition, the combination of pancreatic autoantibodies and antibodies against Saccharomyces cerevisiae antibodies/perinuclear cytoplasmic antibody (pANCA) improved the sensitivity of serological markers in pediatric patients with CD and UC. Some studies suggested that age-associated differences in the patterns of antibodies may be present, particularly in the youngest children. In CD, most patients develop stricturing or perforating complications, and a significant number of patients undergo surgery during the disease course. Based on recent knowledge, serum antibodies are qualitatively and quantitatively associated with complicated CD behavior and CD-related surgery. Pediatric UC is characterized by extensive colitis and a high rate of colectomy. In patients with UC, high levels of anti-CBir1 and pANCA are associated with the development of pouchitis after ileal pouch-anal anastomosis. Thus, serologic markers for IBD can be applied to stratify IBD patients into more homogeneous subgroups with respect to disease progression. In conclusion, identification of patients at an increased risk of rapid disease progression is of great interest, as the application of early and more aggressive pharmaceutical intervention could have the potential to alter the natural history of IBD, and reduce complications and hospitalizations.

关键词： Inflammatory bowel disease, Crohn’ s disease, Ulcerative colitis, Pediatric, Serologic markers, Antimicrobial antibodies, Anti-glycan antibodies, Pancreatic antibodies, Inflammatory bowel disease

Unexpected ecotone dynamics of a sand dune vegetation complex following water table decline

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Journal of Plant Ecology 2016年第1期9卷 40-50页

作者： Csaba Tölgyesi m.rta Zalatnai LászlóErdős Zoltán Bátori Nicole Rosemary Hupp LászlóKörmöczi Department of Ecology University of SzegedSzeged H-6726Hungary Wildlife Biology Program College of Forestry and ConservationUniversity of Montana32 Campus DriveMissoulaMontanaMT 59812USA

Aims Central Hungarian inland dune ranges harbor heterogeneous grassland vegetation with an extensive network of ecotones,arranged perpendicular to topography-driven hydrologic *** area suffers from severe aridification due to climate change and local anthropogenic factors,which have led to a dramatic decline of the water *** a result,groundwater is no longer reachable for lowlying plant communities;thus,we expect they are bound to undergo profound *** study investigates how the plant communities respond to this changing environment over time by monitoring ecotones,since they are frequently the hotspots of ecosystem *** monitored five ecotones along permanent belt transects for 15 years to characterize their dynamic response,and to identify the internal structural changes of the plant communities the ecotones *** Ecotones were delineated with the split moving window *** dynamics of two ecotone parameters,location and contrast,were analyzed with linear regression models incorporating two independent variables:study year as a measure of time since the loss of groundwater,and precipitation as a possible driver of interannual *** internal changes of the patches separated by the ecotones were analyzed using plant functional *** Findings Precipitation had no detectable effect on the ecotone descriptors,but study year influenced ecotones in an unusual *** position of the ecotones appeared to be very stable in time;their dynamics are stationary,not directional as we *** contrasts had clear tendencies;two ecotones disappeared,one new one was formed and two ecotones showed no *** internal changes of the patches over time were dramatic,showing a shift toward more xeric and more open plant assemblages in most stretches of the ***,the dynamic response of the vegetation was not patch expansion ***,but fusion ***,which profoundly restructured the vegetati

关键词： groundwater decline plant functional group sand dune vegetation split moving window stationary ecotone

Effects of chronic and subtoxic chlorobenzenes on adrenocorticotrophic hormone release

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Journal of Environmental Sciences 2015年第8期27卷 165-170页

作者： Zsolt molnár Regina Pálf?ldi Anna László marianna Radács Krisztián Sepp Péter Hausinger László Tiszlavicz Zsuzsanna Valkusz m.rta Gálfi Institute of Applied Science Department of Environmental Biology and Education Gyula Juhász Faculty of Education University of Szeged Department of Pulmonology Faculty of Medicine University of Szeged Department of medical Physics and Informatics Faculty of Medicine University of Szeged Endocrine Unit of First Department of Internal medicine Faculty of Medicine University of Szeged Invasive Cardiology Department Second Department of Internal Medicine and Cardiology Faculty of Medicine University of Szeged Department of Pathology Faculty of Medicine University of Szeged

many environmental chemicals and pesticides have been found to alter neuroendocrine communication in exposed biological objects. The environmental loads have primary and secondary effects that can alter the homeostatic regulation potential. Since it is difficult to avoid human exposition, a potentially important area of research to develop in vivo and in vitro experimental models. In this context, the primary aim of this study was to demonstrate the effects of chlorobenzenes on adrenocorticotrophic hormone（ACTH） release. In our experimental study, male Wistar rats were exposed to 0.1, 1.0 and 10 μg/b.w.（body weight） kg of 1,2,4-trichlorobenzene and hexachlorobenzene（Cl B） mix via gastric tube for 30, 60 or 90 days. At the endpoints of the experiment blood samples were taken and animals were decapitated. Primary,monolayer adenohypophysis cell cultures were prepared by enzymatic and mechanical digestion. The ACTH hormone content in serum and supernatant media was measured by immuno-chemiluminescence assay. The mg2＋-dependent ATPase activity was determined by modified method of martin and Dotty. Significant differences were detected in the hormone release between the control and treated groups. The hormone release was enhanced characteristically in exposed groups depending upon the dose and duration of exposure. The mg2＋-ATPase activity enhanced after chronic and subtoxic Cl B exposition. Light microscopy revealed that the adenohypophysis seemed to be more abundant. Results indicate that Wistar rats exposed to subtoxic Cl B have direct and indirect effects on hypothalamus–hypophysis–adrenal axis.

关键词： Chlorobenzenes Subtoxic Adrenocorticotrophic hormone release mg2+ -dependent ATPase

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Biological therapy in inflammatory bowel diseases:Access in Central and Eastern Europe

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World Journal of Gastroenterology 2015年第6期21卷 1728-1737页

作者： Fanni Rencz m.rta Péntek martin Bortlik Edyta Zagorowicz Tibor Hlavaty Andrzej Sliwczyński mihai m Diculescu Limas Kupcinskas Krisztina B Gecse László Gulácsi Peter L Lakatos Department of Health Economics Corvinus University of Budapest Semmelweis University Doctoral School of Clinical medicine IBD Clinical and Research Centre ISCARE a.s.1~(st) Faculty of Medicine Charles University Department of Gastroenterology The Maria Sklodowska-Curie Memorial Cancer Centre and Institute of Oncology and Medical Center for Postgraduate Education Gastroenterology Unit Department of Internal Medicine V University Hospital Bratislava Public Health Department Health Sciences Faculty Medical University in ?ód? and National Health Fund Department of Gastroenterology and Hepatology Carol Davila University Department of Gastroenterology Medical Academy Lithuanian University of Health Sciences 1~(st) Department of medicine Semmelweis University

Biological drugs opened up new horizons in the management of inflammatory bowel diseases(IBD).This study focuses on access to biological therapy in IBD patients across 9 selected Central and Eastern European(CEE)countries,namely Bulgaria,the Czech Republic,Estonia,Hungary,Latvia,Lithuania,Poland,Romania and *** data on the epidemiology and disease burden of IBD in CEE countries was systematically ***,we provide an estimation on prevalence of IBD as well as biological treatment *** all countries with the exception of Romania,lower biological treatment rates were observed in ulcerative colitis(UC)compared to Crohn’s disease despite the higher prevalence of *** heterogeneity(up to 96-fold)was found in access to biologicals across the CEE ***,Bulgaria,Romania and the Baltic States are lagging behind Hungary,Slovakia and the Czech Republic in their access to *** of reimbursement policy may be one of the factors explaining the differences to a certain extent in Bulgaria,Latvia,Lithuania,and Poland,but association with other possible determinants(differences in prevalence and incidence,price of biologicals,total expenditure on health,geographical access,and cost-effectiveness results)was not *** assume,nevertheless,that healthdeterioration linked to IBD might be valued differently against other systemic inflammatory conditions in distinct countries and which may contribute to the immense diversity in the utilization of biological drugs for *** conclusion,access to biologicals varies widely among CEE countries and this difference cannot be explained by epidemiological factors,drug prices or total health *** in reimbursement policy could contribute to better access to biologicals in some countries.

关键词： Inflammatory bowel diseases Ulcerative colitis Bio

Abscisic Acid Connects Phytohormone Signaling with RNA metabolic Pathways and Promotes an Antiviral Response that Is Evaded by a Self- Controlled RNA Virus

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Plant Communications 2020年第5期1卷 111-128页

作者： Fabio Pasin Hongying Shan Beatriz García maren müller David San León m.rta Ludman David H.Fresno Károly Fátyol Sergi munné-Bosch Guillermo Rodrigo Juan Antonio García Centro Nacional de Biotecnología(CNB-CSIC) 28049 MadridSpain Agricultural Biotechnology Research Center Academia Sinica11529 TaipeiTaiwan Departamento de Biologı´a Evolutiva Ecologı´a y Ciencias AmbientalesFacultad de Biologı´aUniversidad de Barcelona08028 BarcelonaSpain Agricultural Biotechnology Institute National Agricultural Research and Innovation Centre2100 Godoll}oHungary Institute for Integrative Systems Biology(I2SysBio) CSIC-University of Valencia46980 PaternaSpain Present address:College of Horticulture and Gardening Tianjin Agricultural University300384 TianjinChina

A complex network of cellular receptors,RNA targeting pathways,and small-molecule signaling provides robust plant immunity and tolerance to *** maximize their fitness,viruses must evolve control mechanisms to balance host immune evasion and plant-damaging *** genus Potyvirus comprises plant viruses characterized by RNA genomes that encode large polyproteins led by the P1 protease.A P1 autoinhibitory domain controls polyprotein processing,the release of a downstream functional RNAsilencing suppressor,and viral ***,we show that P1Pro,a plum pox virus clone that lacks the P1 autoinhibitory domain,triggers complex reprogramming of the host transcriptome and high levels of abscisic acid(ABA)accumulation.A meta-analysis highlighted ABA connections with host pathways known to control RNA stability,turnover,maturation,and *** changes triggered by P1Pro infection or ABA showed similarities in host RNA abundance and *** and hormone treatment assays showed that ABA promotes plant resistance to potyviral ***,quantitative mathematical modeling of viral replication in the presence of defense pathways supported self-control of polyprotein processing kinetics as a viral mechanism that attenuates the magnitude of the host antiviral ***,our findings indicate that ABA is an active player in plant antiviral immunity,which is nonetheless evaded by a self-controlled RNA virus.

关键词： abscisic acid antiviral immune evasion mathematical modeling viral polyprotein processing Potyvirus RNA metabolism