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Tree clusters migration into alpine tundra,Siberia

Journal of Mountain Science 2022年第12期19卷 3426-3440页

作者： KHARUK Viacheslav I. PETROV II'ya A. im Sergei T. GOlYUKOV Alexey S. DVINSKAYA Maria l. SHUSHPANOV Alexander S. Sukacheu Institute of Forest Federal Scientific CenterRussian Academy of ScienceSiberian BranchAcademgorodok 50/28Krasnoyarsk 660036Russia Siberian Federal University Svobodny str.79Krasnoyarsk 660041Russia Reshetneu Siberian State University of Science and Technology Krasnoyarsky rabochy str.31Krasnoyarsk 66014Russia Tomsk State University Leninastr.36Tomsk 634050Russia

We hypothesize that in mountain windy habitat trees formed clusters(hedges)as adaptive structures for seedlings’rooting,survival,and tress’upslope *** studied hedges formed by Siberian pine(Pinus sibirica du Tour)and larch(larix sibirica ledeb.)within the treeline ecotone in southern Siberian Mountains,investigated hedges formation,evolution,habitat amelioration,and analyzed tree’s growth index(GI)dependence on the eco-climate variables(air temperature,precipitation,soil moisture,wind speed)and relief features(elevation,aspect,slope steepness,and terrain curvature).We conducted a ground survey,measured biometrical parameters of trees and hedges,determined species composition and tree physiognomy,soil types and nutrient contents,and sampled wood cores and applied dendrochronology for trees’GI *** high-resolution satellite scenes for hedge detection and upslope migration,we found that winter winds and soil moisture are the main constraints of trees’settlement and *** formation always links with wind-sheltered microtopography features(boulders,local depressions or felled trees).Once the first tree is established,a positive feedback is aroused that facilitates seedling rooting and in-hedge habitat *** form a streamlined dense“common crown”that mitigates adverse winter wind *** always orient along the prevailing winds,and trees’uphill migration occurs by seedlings establishment within the leeward hedge *** growth facilitates soil formation and *** concentration of nutrients(K,P,N and S)within hedges exceeds the background by 1.5-5.5 *** extension leads to increased snow accumulation that mitigates the influence of desiccation and snow abrasion and mitigates seasonal water *** the extremely harsh windy habitat,inhedge trees present in mat,prostrate or krummholz *** warming,tree stems and even twigs turn *** that GI dependence on the wind speed is insignificant unt

关键词： Treeline Timberline Hedges Tree migration Siberian pine larch Tree growth Siberian mountain forests Wind stress Moisture stress

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Evaluation of Groundwater Quality in the Deep Maastrichtian Aquifer of Senegal Using Multivariate Statistics and Water Quality Index-Based GIS

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Journal of Environmental Protection 2022年第11期13卷 819-841页

作者： Djim M. l. Diongue laila Sagnane Huguette Emvoutou Maria faye ibra D. Gueye Serigne faye Geology Department Cheikh Anta Diop University Dakar Senegal Department of Earth Science University of Douala Douala Cameroon

A regional groundwater quality evaluation was conducted in the deep Maastrichtian aquifer of Senegal through multivariate statistical analysis and a GIS-based water quality index using physicochemical data from 232 boreholes distributed over the whole country. The aim was to 1) identify the water types and likely factors influencing the hydrochemistry, and 2) determine the suitability of groundwater for drinking and irrigation. Results showed that sodium, chloride, and fluoride are highly correlated with electrical conductivity (EC) reflecting the significant contribution of these elements to groundwater mineralization. The principal component analysis evidenced: 1) salinization processes (loaded by Na+, K+, EC, Cl-, F- and HCO3-) controlled by water/rock interaction, seawater intrusion and cation exchange reactions;2) dolomite dissolution loaded by the couple Ca2+ and Mg2+ and 3) localized mixing with upper aquifers and gypsum dissolution respectively loaded by NO3- and SO42-. The hierarchical clustering analysis distinguished four clusters: 1) freshwater (EC = 594 μs/cm) with mixed-HCO3 water type and ionic contents below WHO standard;2) brackish (Na-mixed) water type with moderate mineralization content (1310 μs/cm), 3) brackish (Na-Cl) water type depicted by high EC values (3292 μs/cm) and ionic contents above WHO and 4) saline water with Na-Cl water type and very high mineralization contents (5953 μs/cm). The mapping of the groundwater quality index indicated suitable zones for drinking accounting for 54% of the entire area. The occurrence of a central brackish band and its vicinity, which were characterized by high mineralization, yielded unsuitable groundwater for drinking and agricultural uses. The approach used in this study was valuable for assessing groundwater quality for drinking and irrigation, and it can be used for regional

关键词： Groundwater Quality Index Maastrichtian Statistical Analysis GIS

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Optimization of bio-oil production parameters from the pyrolysis of elephant grass (Pennisetum purpureum) using response surface methodology

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Clean Energy 2024年第5期8卷 241-251页

作者： Sunday C.Ikpeseni Samuel O.Sada Ufuoma J.Efetobor Henry O.Orugba Mathias Ekpu Hilary I.Owamah Jeremiah l.Chukwuneke Solomon Oyebisi Uche P.Onochie Department of Mechanical Engineering Delta State UniversityP.M.B.1AbrakaNigeria Department of Mechanical Engineering Delta State PolytechnicP.M.B.3Otefe-OgharaNigeria Department of Chemical Engineering Delta State UniversityP.M.B.1AbrakaNigeria Department of Civil Engineering Delta State UniversityP.M.B.1AbrakaNigeria Department of Mechanical Engineering Nnamdi Azikiwe UniversityP.M.B.2025AwkaNigeria Department of Civil Engineering Covenant UniversityP.M.B.1023OttaNigeria Department of Civil Engineering The University of the South PacificP.M.B.9072SuvaFiji Department of Mechanical Engineering Delta State University of Science and TechnologyP.M.B.5OzoroNigeria

The need to increase bio-oil yield from biomass and enhance its fuel properties has driven research into optimizing the pyrolysis *** study investigated the influence of three key process parameters—temperature,heating rate,and nitrogen flow rate—on the pyrolysis of elephant grass(Pennisetum purpureum)in a fixed-bed *** surface methodology was used to study the im-pact of the aforementioned variables on bio-oil yield to improve its production *** analysis of the biomass revealed 79.24 wt%volatile matter,14.22 wt%fixed carbon,and 5.86%ash,with ultimate analysis showing 45.44%carbon,5.59%hydrogen,and 40.95%*** high volatile matter content and favourable carbon and hydrogen percentages indicate that elephant grass is a vi-able energy source due to its potential for high bio-oil yield and energy *** resulting bio-oil exhibited a higher heating value of 20.9 MJ/kg,indicating its suitability for various heating applications.A second-order regression model was developed for bio-oil yield,with optimal conditions identified as a temperature of 550°C,a heating rate of 17°C/min,and a nitrogen flow rate of 6 ml/*** study achieved an optimal bio-oil yield of 59.03 wt%,and the model’s high R²value of 0.8683 from analysis of variance analysis confirmed its predictive *** research highlights elephant grass as a sustainable feedstock for bio-oil production,offering valuable insights into optimizing pyrolysis conditions to enhance bio-oil yield,thus advancing biofuel technology.

关键词： renewable energy biomass sustainable feedstock regression model fixed-bed reactor

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Warming hiatus-and evergreen conifers in Altay-Sayan Region,Siberia

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Journal of Mountain Science 2018年第12期15卷 2579-2589页

作者： Viacheslav I.KHARUK Sergei T.im Il'ya A.PETROV Sukachev Institute of Forest Federal Scientific CenterRussian Academy of ScienceSiberian BranchAcademgorodok 50/28Krasnoyarsk660036Russia Siberian Federal University Suobodny str.79Krasnoyarsk 660041Russia Reshetnev Siberian State University of Science and Technology Krasnoyarsky rabochy str.31Krasnoyarsk 660014Russia

"Warming hiatus" occurred in the AltaySayan Mountain Region, Siberia in c. 1997–2014. We analyzed evergreen conifer(EGC) stands area(satellite data) and trees(Siberian pine, Pinus sibirica Du Tour, Siberian fir, Abies sibirica ledeb.) growth increment(dendrochronology data) response to climate variables before and during the hiatus. During the hiatus, EGC area increased in the highlands(>1000 m)(+30%), whereas at low and middle elevations(l.) the EGC area decreased(-7%). The EGC area increase was observed on the rain-ward northwest slopes mainly. In highlands, EGC area increase mainly correlated with summer air temperature, whereas at low and middle elevations EGC area decrease correlated with drought index SPEI and vapor pressure deficit(VPD). EGC mortality(fir and Siberian pine) in lowland was caused by the synergy of water stress(inciting factor) and barkbeetle attacks(contributing factor). Tree growth increment(GI) dynamics differs with respect to elevation. At high elevation(1700 m) GI permanently increased since warming onset, whereas at the middle(900 m) and low elevations(450 m) GI increased until c. 1983 yr. with followed depression. That GI "breakpoint" occurred about a decade before hiatus onset. In spite of growth depression, during hiatus GI was higher than that in pre-warming period. At high elevation, GI positively responded to elevated June temperatures and negatively to moisture increase(precipitation, root zone moisture content, VPD, and SPEI). At low elevation GI negatively responded to June temperatures and positively to moisture increase. For both, low and high elevation, these patterns persisted throughout the study period(1967–2014). On the contrary, at middle elevations GI dependence on climate variables switch after breakpoint year(1983). Before breakpoint, June air temperature(positive correlation) and moisture(negative correlations) controlled GI. Further temperature increase leads GI depression and switched correlation signs

关键词： Growth increment Warming hiatus Warming impact Conifer decline Tree growth Tree mortality Conifer mortality Water stress

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Curvature of Pseudocritical Transition line for Two-Flavor QCD with improved Kogut-Susskind Quarks

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Chinese Physics letters 2017年第4期34卷 18-21页

作者： liang-Kai Wu Xiang-Fei Meng fa.ling Zhang faculty of Science Jiangsu University Zhenjiang 212013 National Supercomputer Center Tianjin 300457

The results on the curvature of a pseudocritical transition line for two-flavor QCD through lattice simulations are presented. The simulations are carried out with Symanzik-improved gauge action and Asqtad fermion action on a lattice 12^3×4 at quark mass am = 0.010. At the imaginary chemical potentials aμ1 = 0.050, 0.150, 0.200, 0.225 and 0.250, we investigate the chiral condensate ψψ, plaquette variable P and imaginary part of Polyakov loop im（l） and their susceptibilities. Analytic continuation from an imaginary chemical potential to a real one is used to obtain the expression for transition temperature as a function of the chemical potential. The curvature is 0.0326（46）.

关键词： QCD Curvature of Pseudocritical Transition line for Two-Flavor QCD with improved Kogut-Susskind Quarks

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White organic light-emitting diodes based on electroplex from polyvinyl carbazole and carbazole oligomers blends

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Chinese Physics B 2010年第3期19卷 546-550页

作者：陈飞鹏徐斌赵祖金田文晶吕萍 im Chan State Key laboratory of Supramolecular Structure and Materials Jilin University Department of Chemistry Zhejiang University Department of Chemistry Konkuk UniversityKorea

White organic light-emitting diodes with a blue emitting material fluorene-centred ethylene-liked carbazole oligomer （Cz6F） doped into polyvinyl carbazole （PVK） as the single light-emitting layer are reported. The optical properties of Cz6F, PVK, and PVK：Cz6F blends are studied. Single and double layer devices are fabri- cated by using PVK： Cz6F blends, and the device with the configuration of indium tin oxide （ITO）/PVK：Cz6F/ tris（8-hydroxyquinolinate）aluminium （Alq3）/liF/A1 exhibits white light emission with Commission Internationale de l＇Eclairage chromaticity coordinates of （0.30, 0.33） and a brightness of 402 cd/m^2. The investigation reveals that the white light is composed of a blue-green emission originating from the excimer of Cz6F molecules and a red emission from an electroplex from the PVK：Cz6F blend films.

关键词： white organic light-emitting diodes electroluminescence electroplex

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Olfactory Response of Trichogramma ostriniae (Hymenoptera: Trichogrammatidae) to Volatiles Emitted by Mungbean Plants

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Agricultural Sciences in China 2011年第4期10卷 560-565页

作者： BAI Shu-xiong WANG Zhen-ying HE Kang-lai im Dae-joon State Key laboratory of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences Beijing 100193 P.R.China National Crop Experiment Station Rural Development Administration Suwon 441-100 Republic of Korea

Intercropping maize with the prostrate variety of mungbean, Vigna radiata （l.） Wilczek which grows flat along the ground can increase parasitism of the eggs of the Asian corn borer, Ostrinia furnacalis （Guenée）, a crucial insect pest of maize in China, by Trichogramma ostriniae Pang Chen. This study investigated the behavioural responses of T. ostriniae to plant volatiles emitted from whole plants, leaves, and flowers of prostrate and erect varieties of mungbean in a 4-armed olfactometer. Female parasitiods were significantly attracted to the odours from some varieties of prostrate mungbean when the visit duration and the number of visits were considered, but were not attracted to the odours from any erect varieties. The attractive odours were shown to emanate from the leaves, rather than from the flowers of prostrate mungbean plants. These results have implications for the augmentation of Trichogramma parasitoids in bio-control of O. furnacalis and other crop pests.

关键词： Trichogramma ostriniae olfactory response Vigna radiata plant volatile

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Detection of H pylori infection by ElISA and Western blot techniques and evaluation of anti CagA seropositivity in adult Turkish dyspeptic patients

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World Journal of Gastroenterology 2006年第33期12卷 5375-5378页

作者： zlem Yilmaz Nazime ■en Ahmet Ali Küpelio■lu kay ■im■ek Department of Microbiology and Clinical Microbiology Faculty of Medicine Dokuz Eylül University Inciralti-35340 Izmir Turkey Department of Pathology Faculty of Medicine Dokuz Eylül University Inciralti-35340 Izmir Turkey Department of Gastroenterology Faculty of Medicine Dokuz Eylül University Inciralti-35340 Izmir Turkey

Aim: To detect H pylori infection and to evaluate the anti CagA seropositivity in adult Turkish dyspeptic patients. METHODS: We evaluated anti-H pylori IgA, IgG and anti-CagA antibodies using commercial enzyme-linked immunoassay (ElISA) and Western blot in dyspeptic Turkish patients. H pylori status was determined by histology and rapid urease testing. RESUlTS: Fifty-six patients were entered. Forty-eight (85.7%) out of the 56 patients were positive for H pylori. H pylori IgG seropositivity was 82.1%, IgA seropositivity 48.2%. CagA ElISA showed that IgG was positive in 50% and IgA in 30.4% of those with H pylori infections. Western blot showed that IgG seropositivity was 80.4% and IgA seropositivity 33.9%. Western blot detected IgG antibodies with reactivity to CagA in 50%, VacA in 62.5%, UreB in 87.5%, UreA in 80.4%, and OMP in 57.1%. None of the tests had a sensitivity and specifi city above 80%. CONClUSION: None of these commercial tests seems clinically useful for H pylori detection in adult dyspeptic patients, while Western blot can give seropositivity and determine anti-CagA, VacA virulence factor status of Turkish dyspeptic patients in the Izmir region.

关键词： H pylori, Serum CagA, Enzyme-linked immunoassay Western blot Serodiagnosis Dyspepticpatients

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immunohistochemical detection of HCV infection in patients with hepatocellular carcinoma and other liver diseases

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World Journal of Gastroenterology 1998年第1期4卷 69-70页

作者： ZHANG li-fa PENG Wen-Wei YAO Ji-lu TANG Yong-Huang 不详

im To detect HCV infection in patients with HCC and other liver diseases by the immunohistochemical method.METHODS The expression of HCV antigen was identified by means of lSAB (labelled streptavidinbiotin) method using antiNS3 monoclonal antibody.RESUlTS The positive rates of HCV antigen in the three groups of HCC, liver cirrhosis and hepatitis were 135% (7/52), 125% (2/16), and 10% (4/40) respectively, while in the samples from patients with constitutional jaundice and normal liver samples, no HCV antigen was found. HCV antigen could be seen in the nuclei and/or cytoplasms of carcinoma cells and/or pericancerous hepatocytes. In HCC, HCV antigen was more often seen in nuclei than in cytoplasms. The positive rate of HCV antigen in pericancerous tissues was higher than that in cancerous tissues.CONClUSION HCV is associated with HCC, and HCV infection enhances the development of liver diseases. HCV affects the initiative period of HCC and induces the malignant phenotypic alteration of hepatocytes..

关键词： Hepatitis C carcinoma,hepatocellular immunohistochemistry liver neoplasms liver diseases

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Comparison of invasive methods and two different stool antigen tests for diagnosis of H pylori infection in patients with gastric bleeding

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World Journal of Gastroenterology 2006年第26期12卷 4206-4210页

作者： Ebru Demiray zlem Yilmaz Cihat Sarkis Müjde Soytürk lkay ■im■ek Department of Microbiology and Clinical Microbiology faculty of Medicine Dokuz Eylül UniversityInciralti 35340 IzmirTurkey Department of Gastroenterology faculty of Medicine Dokuz Eylül UniversityInciralti 35340 IzmirTurkey

Aim： To compare two different H pylori stool antigen tests as noninvasive diagnostic methods. METHODS： The study population consisted of 22 upper gastrointestinal system bleeding patients. Urea breath test （UBT）, rapid urease test （RUT） and histopathological examination were applied to all patients. Stool specimens from these patients were examined by rapid STPIP!HpSA and one step simple H pylori antigen cassette test for the detection of Hpylori antigens. RESUlTS： For these 22 patients, 15 （68.2%） were diagnosed as positive and seven （31.8%） were diagnosed negative for H pylori infection by the gold standard methods. Whereas 10 （45.5%） were positive and 12 （54.5%） were diagnosed negative by the rapid STPIP!HpSA test. The sensitivity, specificity, positive and negative predictive values were 60%, 86%, 90% and 50%, respectively. When compared to the gold standard methods, these differences were not significant. However, six patients （27.3%） were positive, and 16 （72.7%） were negative by the simple H pylori stool antigen cassette test. The sensitivity, specificity, positive and negative predictive values were 33%, 86%, 83% and 38%, respectively. Compared to the gold standard methods, the simple H pylori stool antigen cassette test results were significantly different （P = 0.012）. CONClUSION： Rapid STRIP!HpSA test could be used as a routine diagnostic tool in the microbiology laboratory for assessing clinical significance and eradication control of H pylori in upper gastrointestinal system bleeding patients.

关键词： H pylori Stool antigen test Rapid STRIP!HpSA Simple Hpylori antigen cassette test

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