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Detachable string magnetically controlled capsule endoscopy for the noninvasive diagnosis of esophageal diseases:A prospective,blind clinical study

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World Journal of Gastroenterology 2024年第9期30卷 1121-1131页

作者： Yan-Ling Yang Huang-Wen Qin Zhao-Yu Chen hui-ning fan Yi Yu Wei Da Jin-Shui Zhu Jing Zhang Department of Gastroenterology Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200233China

BACKGROUND Traditional esophagogastroduodenoscopy(EGD),an invasive examination method,can cause discomfort and pain in *** contrast,magnetically controlled capsule endoscopy(MCE),a noninvasive method,is being applied for the detection of stomach and small intestinal diseases,but its application in treating esophageal diseases is not *** To evaluate the safety and efficacy of detachable string MCE(ds-MCE)for the diagnosis of esophageal *** Fifty patients who had been diagnosed with esophageal diseases were pros-pectively recruited for this clinical study and underwent ds-MCE and conven-tional *** primary endpoints included the sensitivity,specificity,positive predictive value,negative predictive value,and diagnostic accuracy of ds-MCE for patients with esophageal *** secondary endpoints consisted of visualizing the esophageal and dentate lines,as well as the subjects'tolerance of the *** Using EGD as the gold standard,the sensitivity,specificity,positive predictive value,negative predictive value,and diagnostic accuracy of ds-MCE for esophageal disease detection were 85.71%,86.21%,81.82%,89.29%,and 86%,***-MCE was more comfortable and convenient than EGD was,with 80%of patients feeling that ds-MCE examination was very comfortable or comfortable and 50%of patients believing that detachable string v examination was very *** This study revealed that ds-MCE has the same diagnostic effects as traditional EGD for esophageal diseases and is more comfortable and convenient than EGD,providing a novel noninvasive method for treating esophageal diseases.

关键词： Clinical trial Detachable string magnetically controlled capsule endoscopy Esophagogastroduodenoscopy Noninvasive diagnosis Esophageal diseases

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Impact of non-ideal UE hardware on cell-free massive MIMO network with centralized operation

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Science China(Information Sciences) 2024年第4期67卷 255-271页

作者： ning LI Pingzhi fan Institute of Mobile Communications Southwest Jiaotong University

This paper investigates the impact of non-ideal user equipment(UE) hardware on a cell-free(CF) massive MIMO(mMIMO) network with centralized operation under spatially correlated channels. The minimum mean-squared error(MMSE) estimator can be derived with the help of the generic non-ideal UE hardware model. It is demonstrated that even if the effective signal-to-noise ratio approaches infinity, pilot contamination and imperfect hardware can cause a non-zero estimation error floor. After that, a lower bound is determined for the ergodic uplink capacity of the centralized CF mMIMO network under non-ideal UE hardware. Moreover, the optimal receive combining vector is obtained to maximize the uplink spectral efficiency(SE). The maximum ratio(MR) and regularized zero-forcing(RZF) combining schemes are offered as alternatives in light of the computational complexity of the MMSE receiver. Comparing the RZF to the MMSE scheme under different levels of hardware impairments, our findings indicate that the RZF receiver suffers a negligible loss in total SE. For MR combining, a novel closed-form uplink achievable SE expression is obtained based on the MMSE estimator and the use-and-then-forget bounding technique. This expression gives vital insights into the achievable uplink performance with UE hardware impairments. Besides, for various hardware impairment factors, the impact of pilot sequence length on average sum SE is disclosed for different receive combining schemes. To increase the overall SE of the max-min fairness scheme, a heuristic fractional power control scheme with UE hardware impairments is developed, which can essentially avoid sacrificing the SE of other UEs while maximizing the SE of the unluckiest UE in the whole network. Finally,our theoretical performance analysis and power control algorithm are validated by simulation results, and fundamental design guidelines are provided for selecting hardware satisfying the practical UE requirements.

关键词： cell-free massive MIMO centralized operation spatially correlated channels hardware impairments channel estimation uplink spectral efficiency optimal receive combining pilot length design fractional power control

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A Novel Multiple DBC-staked units Package to Parallel More Chips for SiC Power Module

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CES Transactions on Electrical Machines and Systems 2024年第1期8卷 72-79页

作者： Xiaoshuang hui Puqi ning Tao fan Yuhui Kang Kai Wang Yunhui Mei Guangyin Lei Institute of Electrical Engineering Chinese Academy of Sciences Beijing 100049China the school of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijing 100190China IEEE the School of Electrical Engineering Tiangong UniversityTianjin 300387China the Academy for Engineering and Technology Fudan UniversityShanghai 200433China

Silicon carbide(SiC) power modules play an essential role in the electric vehicle drive system. To improve their performance, reduce their size, and increase production efficiency, this paper proposes a multiple staked direct bonded copper(DBC) unit based power module packaging method to parallel more chips. This method utilizes mutual inductance cancellation effect to reduce parasitic inductance. Because the conduction area in the new package is doubled, the overall area of power module can be reduced. Entire power module is divided into smaller units to enhance manufacture yield, and improve design freedom. This paper provides a detailed design, analysis and fabrication procedure for the proposed package structure. Additionally, this paper offers several feasible solutions for the connection between power terminals and DBC untis. With the structure, 18dies were paralleled for each phase-leg in a econodual size power module. Both simulation and double pulse test results demonstrate that, compared to conventional layouts, the proposed package method has 74.8% smaller parasitic inductance and 34.9% lower footprint.

关键词： Silicon carbide Electric vehicle Power modules Package

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Distributed Cell-Free Massive MIMO Versus Cellular Massive MIMO Under UE Hardware Impairments

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Chinese Journal of Electronics 2024年第5期33卷 1274-1285页

作者： ning LI Pingzhi fan School of Information Science and Technology Southwest Jiaotong University

This paper first investigates and compares the uplink spectral efficiency(SE) of distributed cell-free massive multiple-input multiple-output(mMIMO) and cellular mMIMO networks, both with user equipment(UE)hardware impairments. We derive a lower bound on the uplink ergodic channel capacity of the cellular mMIMO with UE hardware impairments, based on which we determine the optimal receive combining that maximizes the instantaneous effective signal-to-interference-and-noise ratio. Then, a lower bound on the uplink capacity of a distributed cellfree mMIMO with UE hardware impairments is derived using the use-and-then-forget technique. On this basis, the optimum large-scale fading decoding vector is found using generalized Rayleigh entropy. By using three combining schemes of minimum mean-square error(MMSE), regularized zero-forcing(RZF), and maximum ratio, the uplink SEs of distributed cell-free mMIMO and cellular mMIMO networks are analyzed and compared. The results show that the two-layer decoding distributed cell-free mMIMO network with MMSE combining outperforms the cellular mMIMO network, and the advantage is more evident as the hardware impairment factor increases. Finally, the uplink energy efficiency(EE) of the distributed cell-free mMIMO networks is analyzed and evaluated through the established realistic power consumption model with hardware impairments. Simulation results show that two-layer decoding provides higher SE and EE than single-layer decoding. In addition, RZF achieves almost the same SE and EE as MMSE in a two-layer decoding architecture.

关键词： Massive multiple-input multiple-output (mMIMO) Cell-free mMIMO Cellular mMIMO Hardware impairments Uplink Energy efficiency Optimal receive combining Massive multiple-input multiple-output (mMIMO) Cell-free mMIMO Spectral efficiency Spectral efficiency Hardware impairments Uplink Energy efficiency Optimal receive combining ENERGY EFFICIENCY SYSTEMS NETWORKS DESIGN UPLINK PERFORMANCE

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Study on the clogging mechanism of punching screen in sand control by the punching structure parameters

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Petroleum Science 2024年第1期21卷 609-620页

作者： Fu-Cheng Deng Fu-Lin Gui Bai-Tao fan Lei Wen Sheng-Hong Chen ning Gong Yun-Chen Xiao Zhi-hui Xu Yangtze University Jingzhou434023HubeiChina CNOOC Research Institute Ltd. Beijing100028China CNOOC Ener Tech-Drilling&Production Co. Tianjin300457China Tianjin Branch of CNOOC Ltd. Tianjin300459China

As an independent sand control unit or a common protective shell of a high-quality screen,the punching screen is the outermost sand retaining unit of the sand control pipe which is used in geothermal well or oil and gas ***,most screens only consider the influence of the internal sand retaining medium parameters in the sand control performance design while ignoring the influence of the plugging of the punching screen on the overall sand retaining performance of the *** explore the clogging mechanism of the punching screen,this paper established the clogging mechanism calculation model of a single punching screen sand control unit by using the computational fluid mechanics-discrete element method(CFD-DEM)combined *** to the combined motion of particles and fluids,the influence of the internal flow state on particle motion and accumulation was *** results showed that(1)the clogging process of the punching sand control unit is divided into three stages:initial clogging,aggravation of clogging and stability of *** the initial stage of blockage,coarse particles form a loose bridge structure,and blockage often occurs preferentially at the streamline gathering place below chamfering inside the sand control *** the stage of blockage intensification,the particle mass develops into a relatively complete sand bridge,which develops from both ends of the opening to the center of the *** the stable plugging stage,the sand deposits show a“fan shape”and form a“V-shaped”gully inside the punching slot element.(2)Under a certain reservoir particle-size distribution,The slit length and opening height have a large influence on the permeability and blockage rate,while the slit width size has little influence on the permeability and blockage *** microscopic clogging mechanism and its law of the punching screen prevention unit are proposed in this study,which has some field guidance significance for the design of punching screen

关键词： Punching screen Plugging CFD-DEM Size parameter Sand control

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Electrocatalytic CO2 reduction to syngas

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Green Energy & Environment 2024年第7期9卷 1085-1100页

作者： Bing Chang Zhaojun Min ning Liu Nan Wang Maohong fan Jing fan Jianji Wang School of Environment Key Laboratory of Yellow River and Huai River Water Environment and Pollution Control Ministry of Education Henan Normal University School of Chemistry and Chemical Engineering Key Laboratory of Green Chemical Media and Reactions Ministry of Education Henan Normal University College of Engineering and Physical Sciences and School of Energy Resources University of Wyoming College of Engineering Georgia Institute of Technology

While carbon dioxide （CO2） is a major greenhouse gas,it is also an important C1 *** the trend of energy conservation and emission reduction,electrocatalytic reduction has become a very promising strategy for CO2utilization because it can convert CO2directly to high-valued chemicals and fuels under mild *** particular,the product CO and by-product H2can be combined into syngas by an electrocatalytic CO2reduction reaction （CO2RR） in an aqueous *** molar ratios of CO and H2may be used to produce essential bulk chemicals or liquid fuels such as methanol,alkanes,and olefins through thermochemical catalysis,Fischer–Tropsch synthesis,microbial fermentation,and other *** work discusses the latest strategies in controlling the molar ratio of CO/H2and improving the yield of *** challenges of electrocatalytic syngas production are analyzed from an industrial application perspective,and the possible measures to overcome them are proposed in terms of new catalyst design,electrolyte innovation,flow reactor optimization,anodic reaction coupling,and operando technique application.

关键词： Electrocatalysis CO 2 reduction Syngas Electrolyte Electrolyzer

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Glaucoma surgery experiments using digital microscope-integrated optical coherence tomography and OCT-compatible instruments

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Journal of Innovative Optical Health Sciences 2024年第5期17卷 105-113页

作者： Tianliang Jiang Jinyu fan ning Tang Yi He Guohua Shi School of Biomedical Engineering(Suzhou)Division of Life Sciences and Medicine University of Science and Technology of China Hefei 230026 P.R.China Jiangsu Key Laboratory of Medical Optics Suzhou Institute of Biomedical Engineering and Technology Chinese Academy of Science Suzhou 215163P.R.China

There is a certain failure rate in traditional glaucoma surgery because of the lack of depth information in microscope *** this work,we present a digital microscope-integrated optical coherence tomography(MIOCT)system and several custom-made OCT-compatible instruments for glaucoma *** ophthalmologists were asked to perform trabeculectomy and canaloplasty on live porcine eyes using the system and *** surgery,a subjective feedback survey about the user experience was *** experiment results showed that our system can help surgeons easily locate important tissue structures during *** custom-made instruments also solved the shadowing problem in OCT *** preferred to use the system in their future practice.

关键词： Microscope-integrated optical coherence tomography OCT-compatible instruments glaucoma surgery trabeculectomy canaloplasty

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A review on vanadium extraction techniques from major vanadium-containing resources

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Rare Metals 2024年第9期43卷 4115-4131页

作者： Yin-hui Wang Yi-fan Wang Yu-Ting Li Chang Wu Xiu-Li Han ning-ning Zhao Ze-Kun Zhang Lei Dai Ling Wang Zhang-Xing He College of Mining Engineering North China University of Science and Technology Collaborative Innovation Center of Green Development and Ecological Restoration of Mineral Resources College of Chemical Engineering North China University of Science and Technology

The critical role of vanadium in metallurgy and the increasing commercialization of vanadium redox flow batteries have contributed to a rise in market demand for vanadium, emphasizing the need to ensure the sustainability of vanadium production. Converter vanadium slag and stone coal, generated during the smelting process of vanadium–titanium magnetite, serve as primary raw materials for vanadium extraction. This paper reviews the process mineralogy of converter vanadium slag and stone coal, encompassing the chemical and physical phase compositions of the raw materials and the state of vanadium occurrence. The aim is to establish a theoretical foundation for the mechanistic study of the vanadium extraction techniques and to provide a reference for the optimization of the process afterward. This paper systematically summarizes the current vanadium extraction technology from converter vanadium slag, covering roasting,direct leaching, sub-molten salt method, and the technology and research status of vanadium extraction from stone coal. Most importantly, it identifies key issues in the current vanadium extraction techniques and challenges faced in actual production, based on the analysis of the current vanadium extraction process and mechanism research. The forward feasibility and prospects for the development of vanadium extraction technology are outlined.

关键词： Vanadium

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Tumor microenvironment reprogramming by nanomedicine to enhance the effect of tumor immunotherapy

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Asian Journal of Pharmaceutical Sciences 2024年第2期19卷 1-37页

作者： Yu Huang hui fan huihui Ti School of Chinese Materia Medica Guangdong Pharmaceutical UniversityGuangzhou 510006China Guangdong Province Precise Medicine Big Date of Traditional Chinese Medicine Engineering Technology Research Center Guangdong Pharmaceutical UniversityGuangzhou 510006China School of Pharmacy Guangdong Pharmaceutical UniversityGuangzhou 510006China

With the rapid development of the fields of tumor biology and immunology, tumor immunotherapy has been used in clinical practice and has demonstrated significant therapeutic potential, particularly for treating tumors that do not respond to standard treatment options. Despite its advances, immunotherapy still has limitations, such as poor clinical response rates and differences in individual patient responses, largely because tumor tissues have strong immunosuppressive microenvironments. Many tumors have a tumor microenvironment (TME) that is characterized by hypoxia, low pH, and substantial numbers of immunosuppressive cells, and these are the main factors limiting the efficacy of antitumor immunotherapy. The TME is crucial to the occurrence, growth, and metastasis of tumors. Therefore, numerous studies have been devoted to improving the effects of immunotherapy by remodeling the TME. Effective regulation of the TME and reversal of immunosuppressive conditions are effective strategies for improving tumor immunotherapy. The use of multidrug combinations to improve the TME is an efficient way to enhance antitumor immune efficacy. However, the inability to effectively target drugs decreases therapeutic effects and causes toxic side effects. Nanodrug delivery carriers have the advantageous ability to enhance drug bioavailability and improve drug targeting. Importantly, they can also regulate the TME and deliver large or small therapeutic molecules to decrease the inhibitory effect of the TME on immune cells. Therefore, nanomedicine has great potential for reprogramming immunosuppressive microenvironments and represents a new immunotherapeutic strategy. Therefore, this article reviews strategies for improving the TME and summarizes research on synergistic nanomedicine approaches that enhance the efficacy of tumor immunotherapy.

关键词： Tumor immunotherapy Tumor micr oenvir onment Nanomedicine Tumor repr ogramming

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Study of the blocking mechanism in gravel packing based on CFD-DEM

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Particuology 2024年第7期90卷 164-178页

作者： Fucheng Deng Lei Wen Gang Li Baitao fan ning Gong Shenghong Chen Yangtze University Jingzhou434023China Guangzhou Institute of Energy Conversion Chinese Academy of Sciences510640China CNOOC Research Institute Ltd Beijing100028China Tianjin Branch of CNOOC Ltd Tianjin300459China CNOOC Ener Tech-Drilling&Production Co Tianjin300457China

Gravel packing sand control(GPSC),as the optimization of mechanical sand control technology,is widely used in the deep water completion and sand control of loose sandstone heavy oil reservoirs and highly *** explore the blocking mechanism of GPSC,the influence of its structural parameters on the blocking of GPSC is *** paper establishes a particle element model based on computational fluid dynamics-discrete element method coupling using the discrete element method and establishes a fluid flow model combined with computational fluid dynamics to realize their full coupling *** sand control experiments were carried out using a micro visual sand control simulation device to verify the blocking *** blocking mechanism is analyzed from the microscopic point of view,and then,the influence of sand control structure parameters on the blocking in GPSC design is *** results show the following:(1)the blocking process of GPSC can be divided into three stages:an initial stage,sand accumulation stage,and equilibrium stage.(2)There are two main types of gravel packing *** first type of blocking is blocking on the surface of the gravel *** particles on the surface of gravel layer mainly exist in the form of large particle size blocking gravel pores and sand particles bridging each *** second type of blockage is the blockage inside the gravel *** particles mainly exist in the form of internal mud cakes and adsorption on gravels inside the gravel layer.(3)To ensure the sand control performance of the gravel layer,the gravel layer thickness is designed between 23 and 28 *** displacement or pressure of the on-site packing pump should be increased to ensure that the gravel layer packing solidity ranges between 59%and 62%.In the design of GPSC,it should be ensured that the median particle size of gravel is 5–6 times the median particle size of *** study provides an effective technical reference for the

关键词： CFD-DEM Blocking the process Blocking mechanism Structural parameter

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