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Distribution Approximation of Shrinkage Estimate in Censored Regression Model via Randomly Weighting Method

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Acta Mathematicae Applicatae Sinica 2019年第2期35卷 421-434页

作者： xian-hui LIU Zhan-feng WANG Yao-hua WU Department of Statistics and Finance University of Science and Technology of China School of Statistics and Research Center of Applied Statistics Jiangxi University of Finance and Economics

Censored regression("Tobit") model is a special case of limited dependent variable regression model, and plays an important role in econometrics. Based on this model, all kinds of methods for variable or group variable selection have been developed and the corresponding shrinkage parameter estimates are widely studied. However, asymptotic distributions of the shrinkage estimates involve unknown nuisance parameters,such as density function of error term. To avoid estimating nuisance parameters, this paper presents a randomly weighting method to approximate to the asymptotic distribution of the shrinkage estimate. A computation procedure of random approximation is provided and asymptotic properties of the randomly weighting estimates are also obtained. The proposed methods are evaluated with extensively numerical studies and a women labor supply example.

关键词： Censored regression model variable selection asymptotic properties randomly weighting

Application of vetiver grass Vetiveria zizanioides: Poaceae(L.) as a trap plant for rice stem borer Chilo suppressalis: Crambidae(Walker) in the paddy fields

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Journal of Integrative Agriculture 2019年第4期18卷 797-804页

作者： LU Yan-hui ZHENG Xu-song LU Zhong-xian State Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control Institute of Plant Protection and Microbiology Zhejiang Academy of Agricultural Sciences

Rice is an important staple food in China and it is at risk of attack by rice striped stem borer Chilo suppressalis, which occurs in most rice growing areas. In recent years, severe C. suppressalis outbreaks have been observed in China mainly due to changes in the rice cultivation systems, wide adoption of hybrid varieties and resistance to the dominant insecticides. Management relies primarily on chemical insecticides and resistance is an important contributing factor in these outbreaks. As a result, food safety of agricultural produce is reduced and the ecological and environmental integrities are threatened as well. Recently, environmentally friendly pest management measures, such as trap plants have been introduced for C. suppressalis management and this method can greatly reduce insecticide use. Our previous results indicated that the vetiver grass(Vetiveria zizanioides) is a dead-end trap plant that can effectively attract the adult females of C. suppressalis to lay eggs on it but where larvae are unable to complete their life cycle. This paper further explored the application of vetiver grass as a trap plant to manage C. suppressalis in the paddy fields. This environment-friendly tool can not only reduce C. suppressalis populations, it can also increase the diversity and abundance of natural enemies that can provide better environmental conditions for rice production.

关键词： rice vetiver trap plants Chilo suppressalis control application

Comparison of Two MicroRNA Quantification Methods for Assaying MicroRNA Expression Profiles in Wheat(Triticum aestivum L.)

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Journal of Integrative Agriculture 2014年第4期13卷 733-740页

作者： HAN Ran YAN Yan ZHOU Peng ZHAO hui-xian State Key Laboratory of Crop Stress Biology for Arid Areas/College of Life Sciences Northwest A&F University

Two microRNA （miRNA） quantification methods, namely, poly（A） reverse transcription （RT）-quantitative real-time polymerase chain reaction （qPCR） and stem-loop RT-qPCR, have been developed for quantifying miRNA expression. In the present study, five miRNAs, including miR166, miR167, miR168, miR159, and miR396, with different sequence frequencies, were selected as targets to compare their expression profiles in five wheat tissues by applying the two methods and deep sequencing. The study aimed to determine a simple, reliable and high-throughput method for detecting miRNA expressions in wheat tissues. Results showed that the miRNA expression profiles determined by poly（A） RT-qPCR were more consistent with those obtained by deep sequencing. Further analysis indicated that the correlation coefficients of the data obtained by poly（A） RT-qPCR and deep sequencing （0.739, P≤0.01） were higher than those obtained by stem-loop RT-qPCR and deep sequencing （0.535, P≤0.01）. The protocol used for poly（A） RT-qPCR is simpler than that for stem-loop RT-qPCR. Thus, poly（A） RT-qPCR was a more suitable high-throughput assay for detecting miRNA expression profiles. To the best of our knowledge, this study was the first to compare these two miRNA quantification methods. We also provided useful information for quantifying miRNA in wheat or other plant species.

关键词： Triticum aestivum L. microRNA deep sequencing poly(A) RT-qPCR stem-loop RT-qPCR

Synergistic Effects of Carbon Nanotube(CNT)and Reduced Graphene Oxide(RGO)on Mechanical and Thermal Properties of ZK61 Alloy

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 577-585页

作者： Fanjing Meng Wenbo Du ning Ding Jian Sun xian Du Ke Liu Shubo Li College of Materials Science and Engineering Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China

The hybrid of carbon nanotube(CNT)and reduced graphene oxide(RGO)reinforced ZK61 composite was fabricated by a hot extrusion *** with the raw ZK61 alloy and single-reinforced composites,the hybrid-reinforced by RGO+CNT complex exhibited significant enhancements both in mechanical and thermal *** adjusting the proportion of RGO and CNT in ZK61 alloy,the obtained optimum ZK61/(0.06 wt%RGO+0.54 wt%CNT)composite exhibited increase of 25.4%in yield strength,26.5%in ultimate tensile strength,104%in failure strain and 30.4%in thermal conductivity,respectively,in comparison with ZK61 *** superior properties of the nano-hybrid composite are attributed to the synergetic effects of RGO and CNT,leading to a uniform dispersion and integrated structure as well as the enhanced interfacial bonding with *** strengthening ability of RGO and CNT was calculated to quantify their individual contribution to the improvement in mechanical and thermal properties of the ZK61 matrix *** RGO+CNT hybrids provide a promising way to develop Mg matrix composites with impressive performances.

关键词： Mg matrix composite Carbon nanotube Reduced graphene oxide Mechanical performance Thermal conductivity

Energy Balance-Based SWAT Model to Simulate the Mountain Snowmelt and Runoff——Taking the Application in Juntanghu Watershed(China) as an Example

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Journal of Mountain Science 2015年第2期12卷 368-381页

作者： MENG xian-Yong YU Dan-Lin LIU Zhi-hui School of Resources and Environment Science Xinjiang University Key Laboratory of Oasis Ecology Ministry of Education Xinjiang University Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Department of Earth & Environmental Studies Montclair State University Institute of Arid Ecology and Environment Xinjiang University

In order to predict long-term flooding under extreme weather conditions in central Asia, an energy balance-based distributed snowmelt runoff model was developed and coupled with the Soil and Water Assessment Tool(SWAT) model. The model was tested at the Juntanghu watershed on the northern slope of the Tian Shan Mountains, Xinjiang,China. We compared the performances of temperature-index method and energy balanced method in SWAT model by taking Juntanghu river basin as an application example(as the simulation experiment was conducted in Juntanghu River, we call the energy balanced method as SWAT-JTH). The results suggest that the SWAT snowmelt model had overall Nash-Sutcliffe efficiency(NSE) coefficients ranging from 0.61 to 0.85 while the physical based approach had NSE coefficients ranging from 0.58 to0.69. Overall, on monthly scale, the SWAT model provides better results than that from the SWAT-JTH model. However, results generated from both methods seem to be fairly close at a daily scale. Thestructure of the temperature-index method is simple and produces reasonable simulation results if the parameters are well within empirical ranges. Although the data requirement for the energy balance method in current observation is difficult to meet and the existence of uncertainty is associated with the experimental approaches of physical processes, the SWAT-JTH model still produced a reasonably high NSE. We conclude that using temperature-index methods to simulate the snowmelt process is sufficient, but the energy balance-based model is still a good choice to simulate extreme weather conditions especially when the required data input for the model is acquired.

关键词： SWAT Snowmelt model The physical process Energy balance Temperature-index Water balance

Application of Dorzagliatin in peritoneal dialysis patients with type 2 diabetes mellitus:A case report

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World Journal of Diabetes 2025年第1期16卷 204-210页

作者： Fang Chen Bo An Wen-Cheng An Gang Fu Wei Huang hui-xian Yan Department of Endocrinology Beijing Haidian HospitalBeijing 100080China Department of Nephrology Beijing Haidian HospitalBeijing Haidian Section of Peking University Third HospitalBeijing 100080China

BACKGROUND Treating diabetes in dialysis patients remains a challenge,with many hypoglycemic drugs requiring dose adjustments or avoidance in these *** SUMMARY This report describes an 83-year-old female patient with a 30-year history of type 2 diabetes(T2DM)who had struggled to control her blood sugar for more than a *** had a history of high blood pressure for 30 years,had undergone continuous ambulatory peritoneal dialysis for more than two years,was 163 cm tall,weighed 77 kg,and had a body mass index of 28.98 kg/*** intensive insulin therapy at a daily dose of 150 units,adding Dorzagliatin at a dosage of 75 mg orally twice daily led to immediate blood sugar improvement and a gradual reduction in insulin *** one month of follow-up,the fasting plasma glucose was 6-8 mmol/L,and the 2-hour postprandial glucose was 8-12 mmol/*** To our knowledge,this report is the first to use Dorzagliatin to treat type 2 diabetes peritoneal dialysis patients with challenging glucose ***,a novel glucokinase activator primarily metabolized by the liver,exhibits no pharmacokinetic differences among patients with varying degrees of chronic kidney *** has a high plasma protein binding rate and may not be cleared by peritoneal dialysis,potentially offering a new glycemic control option for Type 2 diabetic patients on peritoneal dialysis.

关键词： Dorzagliatin Type 2 diabetes mellitus Peritoneal dialysis Glucokinase activator Glucose control Case report

Precise Evolutionary Asteroseismology of High-AmplitudeδScuti Star AE Ursae Majoris

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Research in Astronomy and Astrophysics 2022年第10期22卷 61-76页

作者： hui-Fang Xue Jia-Shu Niu Jian-ning Fu Department of Physics Taiyuan Normal UniversityJinzhong 030619China Institute of Computational and Applied Physics Taiyuan Normal UniversityJinzhong 030619China Institute of Theoretical Physics Shanxi UniversityTaiyuan 030006China State Key Laboratory of Quantum Optics and Quantum Optics Devices Shanxi UniversityTaiyuan 030006China Department of Astronomy Beijing Normal UniversityBeijing 100875China

Stellar structure and evolution theory is one of the bases in modern *** inner structures and their evolutionary states can be precisely tested by asteroseismology,since the inner information is brought to the stellar surface by the global oscillating waves and becomes *** stellar evolutionary speed(i.e.,how long timescale does a star stay at a special evolution phase?),because of the insurmountable gap between the timescales of the evolutionary history of human civilization and a star,it can only be roughly tested by ensemble of stars in different evolutionary stages in most cases,and all the snapshots of these stars make up our global view of stellar *** effect of stellar evolution on the structure and the corresponding global size of a pulsating star will lead to tiny period variations of its pulsation modes,which are the most valuable indicators of its evolutionary state and can be used to test the stellar evolution theory by a single star rather than ensemble of ***,we report a High-AmplitudeδScuti star AE Ursae Majoris,which is located in the post main-sequence(MS)evolutionary stage and its observed linear period variation rate can be practically ascribed to its evolutionary *** result tests the stellar evolution theory from the pre-MS to post-MS with an unprecedented precision by a single star,and the framework can be extended to other type of pulsating stars to perform precise evolutionary asteroseismology,which aims to test the current stellar evolution theory in different evolutionary stages,discover the discrepancies between the theory and observations,and ultimately build a complete and precise stellar evolution theory to backtrack the history of each of these stars.

关键词： stars variables delta Scuti-stars evolution-stars oscillations(including pulsations)

Experimental Evaluation on Grinding Texture on Flank Face in Chamfer Milling of Stainless Steel

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Chinese Journal of Mechanical Engineering 2018年第4期31卷 117-123页

作者： xian-Li Liu Jin-Kui Shi Wei Ji Li-hui Wang Harbin University of Science and Technology KTH Royal Institute of Technology

The surface quality of chamfer milling of stainless steel is closed related to the products of 3 C(Computer, Communication and Consumer electronics), where a cutter is a major part to achieve that. Targeting a high-quality cutter,an experimental evaluation is carried out on the influence of grinding texture of cutter flank face on surface *** mathematic models of chamfer cutter are established, and they are validated by a numerical simulation. Also the grinding data are generated by the models and tested by a grinding simulation for safety reasons. Then, a set of chamfer cutting tools are machined in a five-axis CNC grinding machine, and consist of five angles between the cutting edge and the grinding texture on the 1 st flank faces, i.e., 0°, 15°, 30°, 45° and 60°. Furthermore, the machined cutting tools are tested in a series of milling experiments of chamfer hole of stainless steel, where cutting forces and surface morphologies are measured and observed. The results show that the best state of both surface quality and cutting force is archived by the tool with 45° grinding texture, which can provide a support for manufacturing of cutting tool used in chamfer milling.

关键词： Grinding texture Chamfer cutter Cutting force Surface quality

Promotion and Mechanism of Acupotomy on Chondrocyte Autophagy in Knee Osteoarthritis Rabbits

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Chinese Journal of Integrative Medicine 2024年第9期30卷 809-817页

作者： LU Man MENG De-hong SHE Ze-yu WU xian XIA Shuai YANG Kai-ning LIU Cun-bin LI Tao YANG Yong-hui The First Affiliated Hospital of Anhui University of Chinese Medicine Hefei230031China The Second Affiliated Hospital of Anhui University of Chinese Medicine Hefei230038China Department of Acupotomy Rehabilitation Anhui Provincial Hospital of Integrated Traditional Chinese and Western MedicineHefei230031China

Objective:To explore the effect of acupotomy intervention on autophagy of chondrocytes in rabbits with knee osteoarthritis(KOA),and to determine the possible mechanisms of acupotomy to alleviate cartilage ***:The modified Videman method was used to construct a KOA rabbit *** modeling,40 rabbits were randomly divided into 4 groups by a random number table:control;KOA(model);KOA+acupotomy(acupotomy),and KOA+sham acupotomy(sham),10 in each *** a 3-week treatment course,the knee joint activity was determined by the modified Lequesne MG ***-eosin staining staining was used to examine the morphological changes of *** of chondrocytes was observed by transmission electron *** surface morphology of cartilage tissue was observed by scanning electron *** mRNA and protein levels of AMP kinase/mammalian target of rapamycin/Unc-51(AMPK/mTOR/ULK1)signal pathway key proteins,autophagy-related factor Beclin-1 and microtubule-associated protein 1A/1B light chain 3(LC3)in rabbit knee cartilage were assessed by real-time fluorescence quantitative polymerase chain reaction and Western blot,***:The modified Lequesne MG score of acupotomy group was significantly lower than that of model group(P<0.05).Pathological results showed that chondrocyte autophagy decreased and cartilage surface was rough in the model group,which recovered after acupotomy *** mRNA expressions of AMPK,ULK1,Beclin-1 and the protein levels of p-AMPK,p-ULK1,Beclin-1,and LC3Ⅱ/LC3Ⅰwere decreased in the model group,while the mRNA and protein expressions of mTOR were increased(P<0.01).However,acupotomy treatment reversed these abnormal changes(P<0.05).Conclusions:Acupotomy could effectively up-regulate the expressions of AMPK,ULK1 and Beclin1,reduce the expression of mTOR,promote autophagy,and alleviate joint *** is a promising complementary and alternative therapy for KOA.

关键词： acupotomy knee asteoarthritis autophagy AMPK/mTOR/ULK1 signaling pathway rabbit