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Factors limiting the recruitment of Quercus schottkyana,a dominant evergreen oak in SW China

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Plant Diversity 2018年第6期40卷 277-283页

作者： Ke Xia roy Turkington Hong-yu Tan Lei Fan Germplasm Bank of Wild Species Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China Botany Department and Biodiversity Research CentreUniversity of British ColumbiaVancouverBCV6T IZ4Canada Department of Statistics Colorado State UniversityFort CollinsCO80523USA

Quercus schottkyana is a dominant species of oak in the Asian evergreen broad-leaved forests in southwestern China but seedlings are uncommon and recruitment is rare. Annual acorn production by Q. schottkyana is variable and the acorns are exposed to a series of mortality risks. Understanding the factors that limit recruitment of the oak requires knowledge of the oak's life cycle from acorn production to germination and seedling establishment. In this study, we first tested the effects of acorn density on establishment of seedlings by placing batches of acorns at different densities throughout the study ***, we tested the effects of herbivores on seedling survival by erecting fences around both natural and transplanted seedling populations. Our results show that even though the rate of seedling establishment increases as acorn density increases(for 32-8000 acorns?m^(-2)), survival rates of seedlings in the field were generally low(0-0.6%). We show that seedling recruitment of Q. schottkyana is mainly limited to the acorn stage where 88% of the acorns died from the combined effects of desiccation and predation by weevils(Curculio) and bark beetles(Coccotrypes sp.). Herbivory results in the death of some seedlings and consequently also affects the recruitment of seedlings of Q. schottkyana.

关键词： Cyclobalanopsis glaucoides Desiccation Predation Recalcitrant seeds Seedling Yunnan

Correlating mode-I fracture toughness and mechanical properties of heat-treated crystalline rocks

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journal of Rock Mechanics and Geotechnical Engineering 2018年第1期10卷 91-101页

作者： Mayukh Talukdar Debanjan Guha roy T.N.Singh Indian Institute of Technology Bombay PowaiMumbai400076India IITB-Monash Research Academy Indian Institute of Technology BombayPowaiMumbai400076India

For the effect of thermal treatment on the mode-I fracture toughness(FT), three crystalline rocks(two basalts and one tonalite) were experimentally investigated. Semi-circular bend specimens of the rocks were prepared following the method suggested by the International Society for Rock Mechanics(ISRM)and were treated at various temperatures ranging from room temperature(25 ℃) to 600 ℃. Mode-I FT was correlated with tensile strength(TS), ultrasonic velocities, and Young’s modulus(YM). Additionally,petrographic and X-ray diffraction analyses were carried out to find the chemical changes resulting from the heat treatment. Further, scanning electron microscopy(SEM) was conducted to observe the micro structural changes when subjected to high temperatures. These experiments demonstrate that heat treatment has a strong negative impact on the FT and mechanical properties of the rocks. From room temperature to 600 ℃, mode-I FT values of massive basalt, giant plagioclase basalt, and tonalite were reduced by nearly 52%, 68%, and 64%, respectively. Also, at all temperature levels, FT and mechanical properties are found to be exponentially correlated. However, the exact nature of the relationship mainly depends on rock type. Besides, TS was found to be a better indicator of degradation degree than the mode-I FT. SEM images show that micro crack density and structural disintegration of the mineral grains increase with temperature. These physical changes confirm the observed reduction in the stiffness of heat-treated crystalline rocks.

关键词： Fracture toughness(FT) Tensile strength(TS) Ultrasonic velocity Young's modulus(YM) Crystalline rocks

Modeling and analysis of singular systems via orthogonal triangular functions

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控制理论与应用（英文版） 2013年第2期11卷 141-148页

作者： Suchismita GHOSH Anish DEB Srimanti roy CHOUDHURY Gautam SARKAR Department of Electrical Engineering MCKV Institute of Engineering Department of Applied Physics University of Calcutta92 APC RoadKolkata 700009 India Department of Electrical Engineering Budge Budge Institute of Technology Department of Applied Physics University of Calcutta2 APC RoadKolkata 700009 India

This paper presents a new approach to singular system analysis by modeling the system in terms of orthog- onal triangular functions （TFs）. The proposed method is more accurate compared to block pulse function-based analysis with respect to mean integral square error （MISE）. A numerical example involving four states of a singular system is treated and solutions obtained thereof. Four tables and relevant curves are presented to compare the respective coefficients in block pulse function （BPF） domain as well as in TF domain. The percentage error of the samples determined via TF domain are compared with the exact samples of the states. Furthermore, MISE for both BPF and TF analysis are computed and compared to reveal the efficiency of TF-based analysis.

关键词： Singular systems Triangular functions Block pulse functions System analysis Modeling

A new recursive method for the analysis of linear time invariant dynamic systems via double-term triangular functions (DTTF) in state space environment

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控制理论与应用（英文版） 2013年第1期11卷 108-115页

作者： Anish DEB Suchismita GHOSH Srimanti roy CHOUDHURY Gautam SARKAR Department of Applied Physics University of Calcutta Department of Electrical Engineering MCKV Institute of Engineering Department of Electrical Engineering Budge Budge Institute of Technology

This paper presents a new recursive method for system analysis via double-term triangular functions （DTTF） in state space environment. The proposed method uses orthogonal triangular function sets and proves to be more accurate as compared to single term Walsh series （STWS） method with respect to mean integral square error （MISE）. This has been established theoretically and comparison of error with respect to MISE is presented for clarity. A numerical example is treated to establish the proposed method. Relevant curves for the solutions of states of the dynamic system are also presented with plots of percentage error for DTTF-based analysis.

关键词： Double term triangular functions Walsh functions, System analysis Single term Walsh series Mean integral square error (MISE)

Earliest megafossils of scandent calamoid palms from the Deccan Intertrappean Beds of Central India and their paleobiogeographic implications

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journal of Palaeogeography 2024年第3期13卷 509-527页

作者： Sanchita Kumar Kaustav roy Robert A.Spicer Mahasin Ali Khan Palaeobotany and Palynology Laboratory Department of BotanySidho-Kanho-Birsha UniversityRanchi RoadPurulia-723104India CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303Yunnan ProvinceChina School of Environment Earth and Ecosystem SciencesThe Open UniversityMilton KeynesMK76AAUK State Key Laboratory of Tibetan Plateau Earth System Resources and Environment(TPESRE)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

Two well-preserved petrified palm stems from the latest Maastrichtian(Late Cretaceous) to earliest Danian(Early Paleocene) sediments of the Deccan Intertrappean Beds of Madhya Pradesh, Central India are described. Their significant anatomical characteristics include a Calamus-type general stem pattern,the presence of well-preserved fibrovascular bundles(fvbs) with two wide metaxylem vessel elements(230 μm-250 μm) and one phloem strand, uniform density of fvbs, lack of continuity between protoxylem and metaxylem vessel elements, and an absence of centrifugal differentiation of sclerenchymatous fibrous *** features reveal a close resemblance to those of extant genera of scandent Calamoideae. The permineralized stems are described as a new species namely, Palmoxylon calamoides Kumar, roy et Khan sp. *** fossils represent the oldest reliable fossil records of this family, supporting their Gondwanan origin, their importance in tracing their migration pathways from India to Europe and other continents after the docking of the Indian subcontinent with Eurasia during the Paleocene, and an “Out-of-India” dispersal hypothesis. Today the subfamily Calamoideae is disjunctly occurred in Africa, Asia, Australia, Europe, and South America, but the poor deep-time fossil record of this subfamily with a small number of Cenozoic fossils makes hypotheses concerning its origin and dispersal difficult to evaluate. The present study has significant implications for the origin and migration of this subfamily and the paleoclimate.

关键词： Scandent Calamoideae Stem anatomy K-Pg Paleobiogeography Paleoclimate Central India

Ensemble hybrid machine learning methods for gully erosion susceptibility mapping: K-fold cross validation approach

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Artificial Intelligence in Geosciences 2022年第1期3卷 28-45页

作者： jagabandhu roy Sunil Saha Department of Geography University of Gour BangaMalda732103West BengalIndia

Gully erosion is one of the important problems creating barrier to agricultural *** present research used the radial basis function neural network(RBFnn)and its ensemble with random sub-space(RSS)and rotation forest(RTF)ensemble Meta classifiers for the spatial mapping of gully erosion susceptibility(GES)in Hinglo river basin.120 gullies were marked and grouped into four-fold.A total of 23 factors including topographical,hydrological,lithological,and soil physio-chemical properties were effectively *** maps were built by RBFnn,RSS-RBFnn,and RTF-RBFnn *** very high susceptibility zone of RBFnn,RTF-RBFnn and RSS-RBFnn models covered 6.75%,6.72%and 6.57%in Fold-1,6.21%,6.10%and 6.09%in Fold-2,6.26%,6.13%and 6.05%in Fold-3 and 7%,6.975%and 6.42%in Fold-4 of the *** operating characteristics(ROC)curve and statistical techniques such as mean-absolute-error(MAE),root-mean-absolute-error(RMSE)and relative gully density area(R-index)methods were used for evaluating the GES *** results of the ROC,MAE,RMSE and R-index methods showed that the models of susceptibility to gully erosion have excellent predictive *** simulation results based on machine learning are satisfactory and outstanding and could be used to forecast the areas vulnerable to gully erosion.

关键词： K-fold cross-validation Gully erosion susceptibility Radial basis function neural network Hybrid ensemble algorithms R-Index

Glycogen and amyloid-beta: key players in the shift from neuronal hyperactivity to hypoactivity observed in Alzheimer's disease?

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Neural Regeneration Research 2015年第7期10卷 1023-1025页

作者： Britanny Bass Sarah Upson Kamolika roy Emily L.Montgomery Tuula O.jalonen Ian V.j.Murray Department of Physiology and Neuroscience St.George’s University School of Medicine

Introduction：Alzheimer’s disease（AD）begins to develop decades prior to its clinical manifestation（Sperling et al.,2011）,and while it is the most common form of dementia,as of yet there is no *** of the most researched pathological features contributing to disease development are the extracellular amyloid plaques composed of amyloid-beta proteins（Aβ）and neurofibrillary tangles of tau *** feature of AD is the progression of early neuronal excitability/hyperactivity to silencing/hypoactivity（Palop and Mucke,2010）,

关键词： Glycogen and amyloid-beta key players in the shift from neuronal hyperactivity to hypoactivity observed in Alzheimer’s disease

Association between people’s attitudes towards human-elephant conflict and their locational,demographic,and socio-economic characteristics in Buxa Tiger Reserve and its adjoining area,India

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Regional Sustainability 2024年第1期5卷 11-25页

作者： Chiranjib NAD Tamal BASU-roy Department of Geography Raiganj UniversityRaiganj733134India

“Human-elephant conflict(HEC)”,the alarming issue,in present day context has attracted the attention of environmentalists and policy *** rising conflict between human beings and wild elephants is common in Buxa Tiger Reserve(BTR)and its adjoining area in West Bengal State,India,making the area ***’s attitudes towards elephant conservation activity are very crucial to get rid of HEC,because people’s proximity with wild elephants’habitat can trigger the occurrence of *** aim of this study is to conduct an in-depth investigation about the association of people’s attitudes towards HEC with their locational,demographic,and socio-economic characteristics in BTR and its adjoining area by using Pearson’s bivariate chi-square test and binary logistic regression *** is one of the constituent parts of Eastern Doors Elephant Reserve(EDER).We interviewed 500 respondents to understand their perceptions to HEC and investigated their locational,demographic,and socio-economic characteristics including location of village,gender,age,ethnicity,religion,caste,poverty level,education level,primary occupation,secondary occupation,household type,and source of *** results indicate that respondents who are living in enclave forest villages(EFVs),peripheral forest villages(PFVs),corridor village(CVs),or forest and corridor villages(FCVs),mainly males,at the age of 18–48 years old,engaged with agriculture occupation,and living in kancha and mixed houses,have more likelihood to witness ***,respondents who are illiterate or at primary education level are more likely to regard elephant as a main problematic animal around their villages and refuse to participate in elephant conservation *** the sake of a sustainable environment for both human beings and wildlife,people’s attitudes towards elephants must be friendly in a more prudent way,so that the two communities can live in harmony.

关键词： Human-elephant conflict Elephant conservation Chi-square test statistics Binary logistic regression Demographic and socioeconomic characteristics Buxa Tiger Reserve

Role of self-help groups on socioeconomic development and the achievement of Sustainable Development Goals(SDGs)among rural women in Cooch Behar District,India

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Regional Sustainability 2024年第2期5卷 63-74页

作者： Debanjan BASAK Indrajit roy CHOWDHURY Department of Geography and Applied Geography University of North BengalSiliguri734013India

This study examines the transformative role of self-help groups(SHGs)in the socioeconomic development of rural women in Cooch Behar District,India,and their contribution toward achieving Sustainable Development Goals(SDGs)of the United *** this study,we explored the effect of SHGs on rural women by specifically addressing SDGs,such as no poverty(SDG 1),zero hunger(SDG 2),good health and well-being(SDG 3),quality education(SDG 4),and gender equality(SDG 5).Given this issue,a cross-sectional survey and comparison analyses are needed to assess the socioeconomic development of rural women and their awareness level before and after the participation of rural women in *** survey conducted as part of this study was divided into three sections,namely,demographic characteristics,socioeconomic development,and awareness level,with each focusing on different aspects.A group of 400 individuals who were part of SHGs completed the questionnaire survey *** results showed that the participation of rural women in SHGs significantly improved their socioeconomic development and awareness level,as supported by both mean values and t test *** in SHGs and microcredit programs were the major elements that boosted the socioeconomic development of rural women,which also achieves SDGs 1,2,3,4,and *** study revealed that participation in SHGs and related financial services significantly aided rural women in economically disadvantaged communities in accumulating savings and initiating entrepreneurial ***,participation in SHGs was instrumental in enhancing the self-confidence,self-efficacy,and overall self-esteem of rural ***,doing so enabled them to move more freely for work and other activities and to make family and common decisions.

关键词： Self-help groups Rural women Socioeconomic development Sustainable Development Goals(SDGs) Microcredit India