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Withdrawal Intention of Farmers from Vacant Rural Homesteads and Its Influencing Mechanism in Northeast china: A Case Study of Jilin Province

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chinese Geographical Science 2023年第4期33卷 634-648页

作者： YU Jiaping LI Jing lo Kevin HUANG Shanlin Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China Department of Geography Hong Kong Baptist UniversityHong Kong 999077China School of Public Administration and Law Northeast Agricultural UniversityHarbin 150030China

The effective use of land in Northeast china is of great significance for ensuring national food security and regional rural *** this study,based on the survey data collected from Jilin Province,Northeast china,we analyzed the vacancy rates of rural homesteads in suburban,outer suburban,and remote villages,as well as the withdrawal intention of rural-settled farmers,urbansettled farmers,and farmers with urban and rural dual residency from vacant *** the perspective of farmers’perceptions,this study constructed a theoretical framework of the influence mechanism of their withdrawal intention and analyzed such mechanism by constructing a structural equation *** results indicated that:1)rural homestead vacancy rates increased with distance from the village to the city.2)rural-settled farmers showed a low withdrawal intention for vacant rural homesteads,followed by urban and rural dual-residence farmers,and urban-settled farmers showed the highest withdrawal intention.3)the relative importance of the factors influencing withdrawal intention is in the following order:policy awareness>interest perception>living environment perception>family ***,this study discussed the reformation of the homestead system and rural homestead transition in Northeast china,which can provide policy support to increase the potential of cultivated land and promote sustainable rural development and urban-rural coordination.

关键词： village hollowing vacant rural homesteads withdrawal intention influence mechanism Northeast china

TEMPERATURE RESPONSIVE METHACRYLAMIDE POLYMERS WITH ANTIBACTERIAL ACTIVITY

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chinese Journal of Polymer Science 2010年第4期28卷 607-613页

作者：陈伯宽 Shuen-Hung lo Shu-Feng Lee Department of Polymer Materials Kun Shan University

A new methacrylamide monomer, hexylamine methacrylamide （MAHA）, was synthesized and used in polymerizations. The homopolymer of MAHA and its copolymers were synthesized by free radical polymerization techniques with N-isopropyl acrylamide （NIPAAm） in two different compositions. The quatemization of the homopolymer and copolymers were carried out using 1-bromopropane. The copolymers with NIPAAm and a low MAHA content showed temperature-responsive behavior in an aqueous environment. The lower critical solution temperatures （LCSTs） of these polymers varied between 32℃ and 44℃. The LCSTs of quatemized copolymers were higher than those of neutral copolymers because they were more hydrophilic. The obtained homopolymers and copolymers were tested for antibacterial activities against S. aureus and E. coli. The quatemized water-soluble copolymers showed antibacterial activities against S. aureus. The quaternization resulted in the synthesis of both antibacterial and temperature-responsive copolymers.

关键词： Methacrvlamide: NIPAAm: Antibacterial: Temperature-rest)onsive

A path planning algorithm for a crop monitoring fixed-wing unmanned aerial system

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Science china(Information Sciences) 2024年第8期67卷 5-23页

作者： longhao QIAN Yi lok lo Hugh Hong-tao LIU Institute of Aerospace Studies University of Toronto Department of Mechanical Engineering The University of Hong Kong

With the growing demand for automation in agriculture, industries increasingly rely on drones to perform crop monitoring and surveillance. In this regard, fixed-wing unmanned aerial systems(UASs)are viable platforms for scanning a large crop field, given their payload capacity and range. To achieve maximum coverage without landing for battery replacement, an algorithm for producing a minimal required energy survey path is essential. Hence, an energy-aware coverage path planning algorithm is proposed *** constraints for a fixed-wing UAS to fly at low altitudes while achieving full coverage of the crop field are first analyzed. Then, the full path is decomposed into straight-line and U-turn primitives. Finally, an algorithm to calculate a combination of straight-line segments and U-turns is proposed to obtain the path with minimum required energy consumption. The genetic algorithm is used to efficiently determine the order of the straight-line paths to traverse. Case studies show that the proposed algorithm can produce planning results for a convex-polygon-shaped crop field.

关键词： path planning genetic algorithm energy minimization fixed-wing UAS aerial survey

Blue emitting exciplex for yellow and white organic light‑emitting diodes

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Frontiers of Optoelectronics 2023年第4期16卷 191-203页

作者： Kavya Rajeev C.K.Vipin Anjali K.Sajeev Atul Shukla Sarah K.M.McGregor Shih‑chun lo Ebinazar B.Namdas K.N.Narayanan Unni Centre for Sustainable Energy Technologies CSIR-National Institute for Interdisciplinary Science and TechnologyThiruvananthapuram 695019India Academy of Scientifc and Innovative Research(AcSIR) Ghaziabad 201002India Centre for Organic Photonics&Electronics The University of QueenslandBrisbaneQLD 4072Australia School of Mathematics and Physics The University of QueenslandBrisbaneQLD 4072Australia School of Chemistry and Molecular Biosciences The University of QueenslandBrisbaneQLD 4072Australia

White organic light-emitting diodes(WOLEDs)have several desirable features,but their commercialization is hindered by the poor stability of blue light emitters and high production costs due to complicated device ***,we investigate a standard blue emitting hole transporting material(HTM)N,N'-bis(naphthalen-1-yl)-N,N'-bis(phenyl)benzidine(NPB)and its exciplex emission upon combining with a suitable electron transporting material(ETM),3-(biphenyl-4-yl)-5-(4-tert-butylphenyl)-4-phenyl-4H-1,2,4-triazole(TAZ).Blue and yellow OLEDs with simple device structures are developed by using a blend layer,NPB:TAZ,as a blue emitter as well as a host for yellow phosphorescent dopant iridium(III)bis(4-phenylthieno[3,2-c]pyridinato-N,C2')acetylacetonate(PO-01).Strategic device design then exploits the ambipolar charge transport properties of tetracene as a spacer layer to connect these blue and yellow emitting *** tetracene-linked device demonstrates more promising results compared to those using a conventional charge generation layer(CGL).Judicious choice of the spacer prevents exciton difusion from the blue emitter unit,yet facilitates charge carrier transport to the yellow emitter unit to enable additional exciplex *** complementary behavior of the spacer improves the blue emission properties concomitantly yielding reasonable yellow *** overall white light emission properties are enhanced,achieving CIE coordinates(0.36,0.39)and color temperature(4643 K)similar to *** intermolecular exciplex emission in OLEDs simplifes the device architecture via its dual functionality as a host and as an emitter.

关键词： Organic light-emitting diodes Dual functional exciplex Spacers Device design strategy Blue exciplex Yellow OLEDs White light emission

Validated model for prediction of recurrent hepatocellular carcinoma after liver transplantation in Asian population

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World Journal of Gastrointestinal Oncology 2019年第4期11卷 322-334页

作者： Ka Wing Ma Wong Hoi She Albert chi Yan Chan Tan To Cheung James Yan Yue Fung Wing chiu Dai chung Mau lo Kenneth Siu Ho Chok Department of Surgery the University of Hong Kong Department of Surgery and State Key Laboratory for Liver Research the University of Hong Kong Department of Medicine and State Key Laboratory for Liver Research The University of Hong Kong

BACKGROUND Liver transplantation(LT) is regarded as the best treatment for both primary and recurrent hepatocellular carcinoma(HCC). Post-transplant HCC recurrence rate is relatively low but significant, ranging from 10%-30% according to different series. When recurrence happens, it is usually extrahepatic and associated with poor prognosis. A predictive model that allows patient stratification according to recurrence risk can help to individualize post-transplant surveillance protocol and guidance of the use of anti-tumor immunosuppressive *** To develop a scoring system to predict HCC recurrence after LT in an Asian *** Consecutive patients having LT for HCC from 1995 to 2016 at our hospital were recruited. They were randomized into the training set and the validation set in a60:40 ratio. Multivariable Cox regression model was used to identity factors associated with HCC recurrence. A risk score was assigned to each factor according to the odds ratio. Accuracy of the score was assessed by the area under the receiver operating characteristic *** In total, 330 patients were eligible for analysis(183 in training and 147 invalidation). Recurrent HCC developed in 14.2% of them. The median follow-up duration was 65.6 mo. The 5-year disease-free and overall survival rates were78% and 80%, respectively. On multivariate analysis, alpha-fetoprotein > 400 ng/mL [P = 0.012, hazard ratio(HR) 2.92], sum of maximum tumor size and number(P = 0.013, HR 1.15), and salvage LT(P = 0.033, HR 2.08) were found to be independent factors for disease-free survival. A risk score was calculated for each patient with good discriminatory power(c-stat 0.748 and 0.85, respectively,in the training and validation sets). With the derived scores, patients were classified into low-(0–9), moderate-(> 9–14), and high-risk groups(> 14), and the risk of HCC recurrence in the training and validation sets was 10%, 20%, 54%(cstat 0.67) and 4%, 22%, 62%(c-stat 0.811), accordin

关键词： Hepatocellular carcinoma Liver transplantation Post-transplant recurrence Predictive model

Measuring absolute adsorption in porous rocks using oscillatory motions of a spring-mass system

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chinese Journal of Chemical Engineering 2022年第4期35卷 131-139页

作者： Younki Cho Ryan lo Keerthana Krishnan Xiaolong Yin Hossein Kazemi Petroleum Engineering Colorado School of MinesGoldenCO 80401USA

We present an oscillation-based method to measure absolute adsorption,or total gas,contained in porous rocks without and with excess *** conducted with a macroporous Berea sandstone sample in nitrogen where excess adsorption is negligible show that absolute adsorption can be obtained after the added mass of co-accelerated gas outside the sample is *** experiments conducted in propane with a crushed Niobrara shale sample with micro-and mesopores,absolute adsorption included significant excess *** subtracting both the added mass outside the sample and the gas that would be in the sample assuming no excess adsorption existed,estimated excess adsorption of propane is in good agreement with that projected based on capillary condensation of propane in the volume of mesopores.

关键词： Adsorption Porous media Shale Capillary condensation Oscillation

Financial Support Mechanisms and Financing Instruments for Climate Change Adaptation

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Journal of Environmental Protection 2016年第2期7卷 242-252页

作者： Shih-Fang lo Chou-Yen Wu chun-Hsu Lin Center for Green Economy Chung-Hua Institution for Economic Research Taiwan Research Division V Taiwan Institute of Economic Research Taiwan

Extreme weather has been having an increase in frequency and severity because of global warming. Heavy financial burden on governments has been increasing as reconstruction of natural disaster and prevention of public construction spending. Unlike the climate mitigation activities, the main purpose of climate adaptation is to establish climate risk management system. We discuss several types of financing instruments and collect several cases in both developed and developing countries internationally. We find that budget reallocation or government bonds are regularly used for losses from natural disaster in developing countries while both government bonds and insurance penetration are used to against catastrophe risks in the developed countries. Finally, we also find that insurance-related instruments are feasible and have been applied in some middle-income countries with assistance from the World Bank.

关键词： Climate Change Adaptation Insurance Tools Capital Market Review Case Study

Discussion of“optimal reinsurance designs based on risk measures:a review”by Jun Cai and Yichun chi

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Statistical Theory and Related Fields 2020年第1期4卷 23-25页

作者： Ambrose lo Department of Statistics and Actuarial Science The University of IowaIowa CityIAUSA

The academic community should be indebted to Professors Jun Cai and Yichun chi for their meticulously written review paper(referred to as Cai&chi,in press in what follows)on optimal reinsurance,which summarises and sy... 详细信息

关键词： academic Cai insurance

Improved skin regeneration with acellular fish skin grafts

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Engineered Regeneration 2020年第1期1卷 95-101页

作者： Gabriella Fiakos Zeming Kuang Evan lo Stony Brook University Biomedical Engineering100 Nicolls RdStony BrookNew York 11794United States

Fish skin graft,a novel skin substitute,has seen a widespread clinical application since the approval for wound coverage by the *** to its properties in promoting wound healing and its efficient cost in manufacturing,fish skin grafts are a potential alternative to allograft and xenograft sources including,but not limited to cadaver and porcine grafts in a variety of ***,fish skin grafts show promising results in treating diabetic foot ulcers(DFUs),venous leg ulcers(VLUs)and some evidence worthy of further exploration in treating a host of other acute and chronic *** we summarize the material and biological properties of fish skin *** this graft compares to other prevailing skin substitutes on the market for different wound types was also *** skin grafts have many uses in clinical applications of the future.

关键词： Wound healing Chronic wounds Burn wounds Skin xenografts Omega-3 polyunsaturated fatty acid