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Price transmission in hog and feed markets of China

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Journal of Integrative Agriculture 2015年第6期14卷 1122-1129页

作者： zhou De Dieter Koemle College of Economics and Management Nanjing Agricultural University Department of Agricultural Economics and Rural Development University of Gttingen

There is an increasing demand for feed as the industrialization of hog production in China. Land scarcity limits China＇s ability to continue increasing its hog production without feed imports, particularly soybean, and the feed markets are increasingly integrated into the global market. This study performs an analysis of price transmission between the hog price in China and feed prices, specifically domestic maize price and international soybean price, from January 2000 to April 2014. We identified a long-term stable equilibrium relationship between the three markets. However, further analyses show that there is no significant Granger causality between hog and feed market, and the long-run equilibrium partially results from Granger causality between the international soybean market and domestic maize market. This suggests that the domestic hog market has been distorted by different policies. The results also indicate that the efficiency of price transmission is very low and it takes about 11 months to correct one-half of any long-run disequilibrium for the hog market in China. Therefore, to stabilize hog price in China, only market intervention to regulate the maize and soybean markets would be insufficient and comprehensive measures need to be taken into account such as hog production modernization, agricultural insurance, epidemic surveillance etc.

关键词： soybean maize prices surveillance scarcity imports modernization insurance agricultural stabilize

Derivation and application of pluripotent stem cells for regenerative medicine

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Science China(Life Sciences) 2016年第6期59卷 576-583页

作者： Jiaqiang Wang Qi zhou State Key Laboratory of Stem cell and Reproductive Biology Institute of Zoology Chinese Academy of Sciences

Pluripotent stem cells(PSCs) are cells that can differentiate into any type of cells in the body, therefore have valuable promise in regenerative medicine of cell replacement therapies and tissue/organ engineering. PSCs can be derived either from early embryos or directly from somatic cells by epigenetic reprogramming that result in customized cells from patients. Here we summarize the methods of deriving PSCs, the various types of PSCs generated with different status, and their versatile applications in both clinical and embryonic development studies. We also discuss an intriguing potential application of PSCs in constructing tissues/organs in large animals by interspecies chimerism. All these emerging findings are likely to contribute to the breakthroughs in biological research and the prosperous prospects of regenerative medicine.

关键词： pluripotent stem cells regenerative medicine reprogramming interspecies chimerism

Improved photocatalytic activity of nano CuO-incorporated TiO2 granules prepared by spray drying

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Progress in Natural Science:Materials International 2015年第4期25卷 334-341页

作者： Zongjie Liu Chungen zhou School of Materials Science and Engineering Beijing University of Aeronautics and Astronautics

4 wt% CuO–96 wt% TiO2 granules were prepared by a spray drying process. The microstructure and optical property of CuO–TiO2 granules were studied. The results indicate that copper existed in the form of CuO. The spray dried granules possess spherical geometry and smooth surface with grain size in the range of 40–80 μm. CuO–TiO2 has a relatively smaller E g value(2.85 eV) than Ti O2(3.17 eV). The photocatalytic property of CuO–TiO2 granules was investigated by degradation of a model pollutant(the azo dye methyl orange) under the irradiation of the xenon lamp equipped with a band pass fi lter of 365 nm. The CuO–TiO2spray-dried granules degrade about 10% more MO than TiO2spray-dried granules under UV irradiation within the same time. The XPS spectra suggested that Cu2 tand reduced copper species were coexistent in reacted CuO–TiO2 photocatalyst. The improvement of photocatalytic activity for CuO–TiO2 was mainly attributed to effective separation of photogenerated electron–hole pairs in the presence of CuO.

关键词： CuO–TiO2 Spray drying Photocatalytic degradation

MCIF-Transformer Mask RCNN:Multi-Branch Cross-Scale Interactive Feature Fusion Transformer Model for PET/CT Lung Tumor Instance Segmentation

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Computers, Materials & Continua 2024年第6期79卷 4371-4393页

作者： Huiling Lu Tao zhou School of Medical Information&Engineering Ningxia Medical UniversityYinchuan750004China School of Computer Science and Engineering North Minzu UniversityYinchuan750021China Key Laboratory of Image and Graphics Intelligent Processing of State Ethnic Affairs Commission NorthMinzu UniversityYinchuan750021China

The precise detection and segmentation of tumor lesions are very important for lung cancer computer-aided ***,in PET/CT(Positron Emission Tomography/Computed Tomography)lung images,the lesion shapes are complex,the edges are blurred,and the sample numbers are *** solve these problems,this paper proposes a Multi-branch Cross-scale Interactive Feature fusion Transformer model(MCIF-Transformer Mask RCNN)for PET/CT lung tumor instance segmentation,The main innovative works of this paper are as follows:Firstly,the ResNet-Transformer backbone network is used to extract global feature and local feature in lung *** pixel dependence relationship is established in local and non-local fields to improve the model perception ***,the Cross-scale Interactive Feature Enhancement auxiliary network is designed to provide the shallow features to the deep features,and the cross-scale interactive feature enhancement module(CIFEM)is used to enhance the attention ability of the fine-grained ***,the Cross-scale Interactive Feature fusion FPN network(CIF-FPN)is constructed to realize bidirectional interactive fusion between deep features and shallow features,and the low-level features are enhanced in deep semantic ***,4 ablation experiments,3 comparison experiments of detection,3 comparison experiments of segmentation and 6 comparison experiments with two-stage and single-stage instance segmentation networks are done on PET/CT lung medical image *** results showed that APdet,APseg,ARdet and ARseg indexes are improved by 5.5%,5.15%,3.11%and 6.79%compared with Mask RCNN(resnet50).Based on the above research,the precise detection and segmentation of the lesion region are realized in this *** method has positive significance for the detection of lung tumors.

关键词： PET/CT images instance segmentation mask RCNN interactive fusion transformer

Molecular Dynamics Simulations of Stretch-Induced Crystal Changes in Crystallized Polyethylene/Carbon Nanotubes Nanocomposites

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Chinese Journal of Polymer Science 2023年第9期41卷 1425-1438,I0007页

作者： Yu-Hang zhou Jun Yang Zhi-Ping zhou Tong-Fan Hao Yi-Jing Nie Research School of Polymeric Materials School of Materials Science and EngineeringJiangsu UniversityZhenjiang212013China

Understanding deformation mechanisms in semi-crystalline polymers during stretching is useful for guiding the processing of highperformance polymer products. In the current work, molecular dynamics simulations were performed to investigate the crystal changes in crystallized polyethylene/carbon nanotube nanocomposites during uniaxial stretching. Both crystal fragmentation and melting occur at low strains. Crystals with small sizes are easier to melt, while those with large sizes would break into smaller crystals. In addition, crystals in interfacial regions are more likely to melt or break due to the orientation motion of carbon nanotubes. It was also found that the recrystallization process is closely related to the stretch-induced orientation of chain segments. After orientation of chain segments along stretching direction is saturated,the recrystallization of highly oriented segments dominates. The current simulation findings are effective complements to the theories of the mechanism of plastic deformation in semicrystalline polymers.

关键词： Molecular dynamics simulation Carbon nanotubes Stretching Melting and recrystallization

Conducting Graphene Decorated Li3V2（PO4）3/C for Lithium- Ion Battery Cathode with Superior Rate Capability and Cycling Stability

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Chinese Journal of Chemistry 2016年第8期34卷 795-800页

作者： Pan zhou Dawei He Key Laboratory of Luminescence and Optical Information Ministry of Education Institute of Optoelectronic Technology Beo'ing Jiaotong University Beijing 100044 China

In this study, core‐shell structured Li 3 V 2 (PO 4 ) 3 /C wrapped in graphene nanosheets has been successfully prepared. The reduction of graphene oxide and the synthesis of Li 3 V 2 (PO 4 ) 3 /C are carried out simultaneously using a chemical route followed by a solid‐state reaction. The effects of conducting graphene are studied by X‐ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectra and electrochemical measurements. The results reveal that the graphene sheets not only form a compact and uniform coating layer throughout the Li 3 V 2 (PO 4 ) 3 /C, but also stretch out and cross‐link into a conducting network around the Li 3 V 2 (PO 4 ) 3 /C particles. Thus, the graphene decorated Li 3 V 2 (PO 4 ) 3 /C electrode exhibits superior high‐rate capability and long‐cycle stability. It delivers a reversible discharge capacity of 178.2 mAh·g −1 after 60 cycles at a current density of 0.1 C, and the rate performances of 176, 169.3, 156.1 and 135.7 mAh·g −1 at 1, 2, 5 and 10 C, respectively. The superior electrochemical properties make the graphene decorated Li 3 V 2 (PO 4 ) 3 /C composite a promising cathode material for high‐performance lithium‐ion battery.

关键词： lithium‐ion battery cathode material Li3V2(PO4)3/C graphene nanosheet electrochemical performance

Smart bioelectronics and biomedical devices

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Bio-Design and Manufacturing 2022年第1期5卷 1-5页

作者： Nanjia zhou Liang Ma Key Laboratory of 3D Micro/Nano Fabrication and Characterization of Zhejiang Province School of EngineeringWestlake UniversityHangzhou 310024China Institute of Advanced Technology Westlake Institute for Advanced StudyHangzhou 310024China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310058China School of Mechanical Engineering Zhejiang UniversityHangzhou 310058China

The development of smart bioelectronics and biomedical devices has significantly advanced the field of biomedical engineering,enabling a myriad of applications from basic biomedical research to clinical medicine and *** at the intersection of materials science,mechanical,electrical,and bioengineering,this fascinating field has attracted considerable attention from researchers all over the world,providing new healthcare solutions which were impossible *** brain–machine interface to biomedical nano/micro-robots,different materials and manufacturing methodologies have been developed to advance the functionalities of the bioelectronic systems to meet the ever-increasing demand of biological and bioinspired applications(Fig.1).

关键词： Smart interface electrical

Quantifying spatial scale of positive and negative terrains pattern at watershed-scale:Case in soil and water conservation region on Loess Plateau

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Journal of Mountain Science 2017年第8期14卷 1642-1654页

作者： YANG Feng zhou Yi School of Geography and Tourism Shaanxi Normal University

The positive and negative terrains(P-N terrains) widely distributed across China's Loess Plateau constitute the dual structure characteristic of loess landforms. Analysis of loess P-N terrains at the watershed scale can serve to elucidate the structural characteristics and spatial patterns of P-N terrains, which benefits a better understanding of watershed evolution and suitable scales for loess landform research. The Two-Term Local Quadrat Variance Analysis(TTLQV) is calculated as the average of the square of the difference between the block totals of all possible adjacent pairs of block size, which can be used to detect both the scale and the intensity of landscape patches(e.g., plant/animal communities and gully networks). In this study, we determined the latitudinal and longitudinal spatial scale of P-N terrain patterns within 104 uniformly distributed watersheds in our target soil and water conservation region. The results showed that TTLQV is very effective for examining the scale of P-N terrain patterns. There were apparently three types of P-N terrain pattern in latitudinal direction(i.e., Loess Tableland type, Loess Hill type, and Transitional Form between Sand and Loess type), whereas there were both lower and higher values for P-N terrain pattern scales in all loess landforms in the longitudinal direction. The P-N terrain pattern alsoclearly presented anisotropy, suggesting that gully networks in the main direction were well-developed while others were relatively undeveloped. In addition, the relationships between the first scales and controlling factors(i.e., gully density, nibble degree, watershed area, mean watershed slope, NDVI, precipitation, loess thickness, and loess landforms) revealed that the first scales are primarily controlled by watershed area and loess landforms. This may indicate that the current spatial pattern of P-N terrains is characterized by internal force. In selecting suitable study areas in China' Loess Plateau, it is crucial to u

关键词： Positive and negative terrains TTLQV Spatial pattern scale Loess landforms Loess Plateau

Improved smoothed L0 reconstruction algorithm for ISI sparse channel estimation

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The Journal of China Universities of Posts and Telecommunications 2014年第2期21卷 40-47页

作者： LIU Ting zhou Jie Department of Communications Nanjing University of Information Science and Technology Department of Electronic and Electrical Engineering Niigata University

In this paper, the problem of inter symbol interference （ISI） sparse channel estimation in wireless communication with the application of compressed sensing is investigated. However, smoothed L0 norm algorithm （SL0） has ＇notched effect＇ due to the negative iterative gradient direction. Moreover, the property of continuous function in SL0 is not steep enough, which results in inaccurate estimations and low convergence. Afterwards, we propose the Lagrange multipliers as well as Newton method to optimize SL0 algorithm in order to obtain a more rapid and efficient signal reconstruction algorithm, improved smoothed L0 （ISL0）. ISI channel estimation will have a direct effect on the performance of ISI equalizer at the receiver. So, we design a pre-filter model which with no considerable loss of optimality and do analyses of the equalization methods of the sparse multi-path channel. Real-time simulation results clearly show that the ISL0 algorithm can estimate the ISI sparse channel much better in both signal noise ratio （SNR） and compression levels. In the same channel conditions, ISL0 algorithm has been greatly improved when compared with the SL0 algorithm and other compressed-sensing algorithms.

关键词： compressed-sensing channel model ISI improved SLO algorithm sparse channel estimation MIMO system