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Natural radioactive environment of urban soils in Shihezi, China

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Nuclear Science and Techniques 2009年第6期20卷 335-339页

作者： GE Benwei LIU anna College of Tourism and Environment Shaanxi Normal University Xi＇an Shaanxi 710062 China Department of Geography Shihezi University Shihezi Xinjiang 832000 China

Radionuclides, such as 238U, 232Th and 40K, can be found in urban soil. To evaluate the natural radioactivity in the environment, soil samples were collected form Shihezi city and radioisotope concentrations were determined by X-ray fluorescence. The dose rate of urban soil (mGy per year, mGy/a) was calculated. The results indicate that the U, Th and K concentrations of the urban soils were, respectively, 1.2-3.2 mg/kg, 6.4-12.3 mg/kg and 2.05%-2.24%, with the mean values of 2.47 mg/kg, 10.47 mg/kg and 2.16 %. Dose rates of urban soils were 10.04-19.55 mGy/a with the mean value of 16.31 mGy/a. This dose rate is the perfect and maximum value of natural radiation in soil and different with the air absorbed dose rate from terrestrial γ-rays. The mean value of air absorbed dose rate was about 57.42 nGy/h. The annual effective dose rate in air was about 0.07 mSv/a and the average value of Raeq in urban soil was 120.37 Bq/kg. The relative contribution of α particle to the dose rate is higher than that derived from β- and γ-rays in the urban soils.

关键词：城市土壤放射性环境天然放射性石河子市中国放射性同位素剂量率放射性核素

SHEAR BEAM MODEL FOR INTERFACE FAILURE UNDER ANTIPLANE SHEAR(Ⅱ)—INSTABILITY

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Applied Mathematics and Mechanics(English Edition) 2000年第11期21卷 1229-1236页

作者：沈新普 Zenon mroz Department of Mechanics Northeastern UniversityShenyang 110006P R China Institute of Fundamental Technological Research Polish Academy of SciencesWarsawPoland

Based on the (Ⅰ) of the present work, the behavior of shear beam model at crack initiation stage and at instable propagation stage was studied. The prime results include: 1) discriminant equation which clarifies the mode of instability, snap_back or snap_through, was established; 2) analytical solution was given out for the double shear beam and the load_displacement diagram for monotonic loading was presented for a full process; and 3) the problem of the energy release induced by instability was discussed.

关键词： interface layer antiplane shear failure shear beam model instability snap_through snap_back dam?

Perception of artificial conspecifics by bearded dragons(Pogona vitticeps)

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Integrative Zoology 2019年第2期14卷 214-222页

作者： anna FROHNWIESER Thomas W.PIKE John C.MURRAY anna WILKINSON School of Life Sciences University of LincolnLincolnUK School of Computer Science University of LincolnLincolnUK Wildlife Research Center Kyoto UniversityKyotoJapan

Artificial animals are increasingly used as conspecific stimuli in animal behavior ***,researchers often have an incomplete understanding of how the species under study perceives conspecifics,and,hence,which features are needed for a stimulus to be perceived *** investigate the features that bearded dragons(Pogona vitticeps)attend to,we measured their lateralized eye use when assessing a successive range of *** ranged through several stages of realism in artificial conspecifics,to see how features such as color,the presence of eyes,body shape and motion influence *** found differences in lateralized eye use depending on the sex of the observing bearded dragon and the artificial conspecific,as well as the artificial conspecific’s ***,this approach can inform the design of robotic animals that elicit biologically-meaningful responses in live animals.

关键词： bearded dragons conspecifics lateralized eye use perception

Influences of Catch Crop and Its Incorporation Time on Soil Carbon and Carbon-Related Enzymes

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Pedosphere 2015年第4期25卷 569-579页

作者： anna PIOTROWSKA-DLUGOSZ Edward WILCZEWSKI Department of Soil Science and Soil Protection Division of Biochemistry Faculty of Agriculture and Biotechnology UTP University of Science and Technology Department of Agrotechnology Faculty of Agriculture and Biotechnology UTP University of Science and Technology

Catch crops that are cultivated for green manure play an important role in improving soil properties. A 3-year field experi- ment was conducted to investigate the effect of catch crop （pea, Pisum sativum L.） management, i.e., incorporation of catch crop in October/November （autumn） and March （spring）, and without catch crop （control）, on soil organic carbon （SOC）, microbial biomass carbon （MBC） and the activities of carbon （C）-cycle enzymes, including cellulase （Cel）, β-glucosidase （Glu） and invertase （Inv）. Additionally, soil total nitrogen （TN） and pHKcl were investigated. The catch crop was cultivated from August to October each year during 2008-2010. Soil samples were collected from the field of spring barley （Hordeum vulgate L.） that had been grown after the catch crop. Soil samples for microbial activity determination were taken in March, May, June and August in 2009, 2010 and 2011, while SOC and TN contents as well as pHKc1 were determined in March and August. The chemical properties studied did not show significant changes as influenced by the experimental factors. The use of catch crop significantly increased the MBC content and the activities of C-cycle enzymes compared to the control. When the catch crop was incorporated in spring, a significantly higher MBC content was noted in March and May compared to autumn incorporation. Moreover, the spring incorporation of the catch crop significantly increased the Glu activity （except March）, while the activities of Cel and Inv as well as the rate of soil basal respiration were usually unaffected by the time of catch crop incorporation. Greater microbial biomass and higher enzyme activities in the catch crop-treated soil, compared to the control, indicated that the application of the catch crop as a green manure could be recommended as a promising technique to increase the biological activity of the soil. Since there was no significant effect or no consistent results were obtained related to the time of catch crop

关键词： cellulase β-glucosidase invertase microbial biomass carbon soil basal respiration

Competition of insect decomposers over large vertebrate carrion:Necrodes beetles(Silphidae)*** flies(Calliphoridae)

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Current Zoology 2022年第6期68卷 645-656页

作者： Szymon MATUSZEWSKI anna MADRA-BIELEWICZ Laboratory of Criminalistics Adam Mickiewicz UniversityPoznan 61-809Poland Wielkopolska Centre for Advanced Technologies Adam Mickiewicz UniversityPoznan 61-614Poland

Large carrion is inhabited by highly variable and interactive communities of *** interactions in carrion insect communities have been recently the focus in carrion *** contrast,competition between carrion insects is rather *** we provide evidence that blow flies(Calliphoridae)and Necrodes beetles(Silphidae),dominant decomposers of large carcasses in terrestrial habitats,compete over *** reanalyzing the results from 90 pig carcasses,we demonstrated that the contribution of the flies and the beetles to the decay was negatively *** greater part of the large carrion pool was monopolized by blow flies,whereas Necrodes beetles abundantly colonized carcasses,on which blow flies were less effective as *** behavioral assays,we found that adult beetles killed 4 times more frequently feeding than postfeeding third instar larvae of the flies,with the large decrease in the killing frequency after the larvae reached the age of early third ***,adult Necrodes beetles preferentially killed the larvae that were before or in their peak *** study provides evidence that the interaction between blow flies and Necrodes beetles is a combination of indirect exploitative effects of the flies and direct interference effects of the beetles(the mixed competition).

关键词： carrion competition interspecific interactions

The Middle-aged and Knowledge Workers: Demographic and Economic Changes in the Pearl River Delta, China

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Chinese Geographical Science 2022年第2期32卷 268-284页

作者： FENG Pengfei anna GROWE SHEN Yuming College of Resources Environment&TourismCapital Normal UniversityBeijing 100048China Institute of Geography Heidelberg UniversityBerliner Strafie 48D-69120 HeidelbergGermany

Demographic and economic development can be seen as two sides of one coin in the process of regional *** article deals with how economic and demographic changes influence the settlement structure and development of the Pearl River Delta(PRD)and lead to regionalization processes within the large *** aim of the study was to understand the interrelation between the three aspects:economic change,demographic change and change of spatial *** on population age and occupational data,spatial changes in demographic structure and economic activities from 2000 to 2010 were *** was found that the demographic and economic change reflected changing spatial patterns between the urban centers and the hinterland in the *** processes were apparent during the studied period in the hinterlands and the high-density areas of the *** one hand,the hinterlands in the PRD attracted more manufacturing activities,while the inner high-density areas experienced a decrease in manufacturing,associated with an increase in young labor in regions where workplaces that only required limited education *** the other hand,specialization in knowledge-intensive business services increased in the inner high-density areas,which also saw an increased share in the older *** finding suggests that increasing knowledge-intensive work correlates with higher age structures due to the longer formal education required and also the benefits knowledge workers accrue through experience and gained knowledge over ***,based on a transformation process,we tentatively conclude that the populations in high-density areas in the PRD became more middle-aged and were represented by more knowledge workers.

关键词： manufacturing knowledge-intensive business services(KIBS) economic change demographic change Pearl River Delta

Carcinoembryonic antigen inhibits neutrophil activation by N-formyl-methionyl-leucyl-phenylalanine

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BIOCELL 2015年第2期39卷 1-3页

作者： anna PAŃCZYSZYN anna KROP-WATOREK Maciej WIECZOREK University of Opole Department of Biotechnology and Molecular BiologyOpolePoland Ludwik Hirszfeld Institute of Immunology and Experimental Therapy Polish Academy of SciencesWroclawPoland

Carcinoembryonic antigen(CEA)is a surface glycoprotein expressed in human epithelial cells and is released from their surface,especially during colorectal ***,colorectal cancer is accompanied by inflammation,where tumor-infiltrating neutrophils play an important *** was also found to be a strong chemotactic agent for *** purpose of this study was to find out if CEA can enhance neutrophil priming and *** neutrophils were activated by N-formyl-methionyl-leucyl-phenylalanine(formyl-MLP)and the resulting oxidative burst was measured ***,in vitro priming of neutrophils by CEA,alone or preceded by LPS,inhibited subsequent activation of these cells by *** may have anti-inflammatory properties in vivo.

关键词： CEA oxidative burst formyl-MLP

Overexpression of Arabidopsis thaliana cysteine2/histidine2-type transcription factor 6 gene enhances plant resistance to a bacterial pathogen

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Journal of Forestry Research 2021年第1期32卷 249-262页

作者： Wei Tang anna Y.Tang College of Arts and Science East Carolina UniversityGreenvilleNC 27858USA 2 Stadium Drive University of North Carolina at Chapel HillChapel HillNC 27514USA

Transcription factors can be used to engineer plants for enhanced ***,the mechanism(s)by which the C2H2-type zinc fi nger transcription factor enhances pathogen resistance in cells is not fully ***,Agrobacterium tumefaciens carrying the gene for Arabidopsis thaliana cysteine2/histidine2-type transcription factor 6(ZAT6)was used to engineer rice(Oryza sativa L.),cotton(Gossypium hirsutum L.),and slash pine(Pinus elliottii Engelm.)to generate transgenic cell *** cells were then inoculated with the pathogenic bacterium Pseudomonas *** to the control,cell viability of transgenic cells increased 39–47%and growth rate increased 9–15%by 7 days after inoculation in rice,cotton and slash *** phosphatase activity and alkaline phosphatase activity and transcript levels of Ca 2+-dependent protein kinase genes OsCPK1,OsCPK2,OsCPK6,and OsCPK8 and mitogen-activated protein kinase genes OsMAPK1,OsMAPK2,OsMAPK3,and OsMAPK8 increased signifi cantly in transgenic rice cells by 3 day after inoculation,and extracellular pH had decreased by 10–14%by 96 min after inoculation in transgenic rice,cotton and slash pine *** results suggest that ZAT6 enhances *** resistance in plant cells by modulating transcription of CPK and MAPK and oxidase activity.

关键词： Ca^2+-dependent protein kinase Mitogenactivated protein kinase Oxidase Pathogen Pinus

Molecular signaling involving intrinsically disordered proteins in prostate cancer

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Asian Journal of Andrology 2016年第5期18卷 673-681页

作者： anna Russo Sara La Manna Ettore Novellino anna Maria Malfitano Daniela Marasco Department of Pharmacy Centro Interuniversitario di Ricerca sui Peptidi Bioattivi University of Naples 'Federico II' 80134 Naples Italy

Investigations on cellular protein interaction networks （PINs） reveal that proteins that constitute hubs in a PIN are notably enriched in Intrinsically Disordered Proteins （IDPs） compared to proteins that constitute edges, highlighting the role of IDPs in signaling pathways. Most IDPs rapidly undergo disorder-to-order transitions upon binding to their biological targets to perform their function. Conformational dynamics enables IDPs to be versatile and to interact with a broad range of interactors under normal physiological conditions where their expression is tightly modulated. IDPs are involved in many cellular processes such as cellular signaling, transcriptional regulation, and splicing; thus, their high-specificity/low-affinity interactions play crucial roles in many human diseases including cancer. Prostate cancer （PCa） is one of the leading causes of cancer-related mortality in men worldwide. Therefore, identifying molecular mechanisms of the oncogenic signaling pathways that are involved in prostate carcinogenesis is crucial. In this review, we focus on the aspects of cellular pathways leading to PCa in which IDPs exert a Iorimary role.

关键词： inflammation intrinsically disordered proteins prostate cancer