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High-Precision Doppler Frequency Estimation Based Positioning Using OTFS Modulations by Red and Blue Frequency Shift Discriminator

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China Communications 2024年第2期21卷 17-31页

作者： Shaojing Wang Xiaomei Tang jing Lei Chunjiang Ma chao Wen Guangfu sun School of Electronic Science National University of Defense TechnologyChangsha 410073China

Orthogonal Time Frequency and Space(OTFS) modulation is expected to provide high-speed and ultra-reliable communications for emerging mobile applications, including low-orbit satellite communications. Using the Doppler frequency for positioning is a promising research direction on communication and navigation integration. To tackle the high Doppler frequency and low signal-to-noise ratio(SNR) in satellite communication, this paper proposes a Red and Blue Frequency Shift Discriminator(RBFSD) based on the pseudo-noise(PN) *** paper derives that the cross-correlation function on the Doppler domain exhibits the characteristic of a Sinc function. Therefore, it applies modulation onto the Delay-Doppler domain using PN sequence and adjusts Doppler frequency estimation by red-shifting or blue-shifting. Simulation results show that the performance of Doppler frequency estimation is close to the Cramér-Rao Lower Bound when the SNR is greater than -15dB. The proposed algorithm is about 1/D times less complex than the existing PN pilot sequence algorithm, where D is the resolution of the fractional Doppler.

关键词： channel estimation communication and navigation integration Orthogonal Time Frequency and Space pseudo-noise sequence red-blue frequency shift discriminator

Bismuth-free Mg_(3)Sb_(2) with enhanced room-temperature thermoelectric and mechanical properties

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Journal of Materiomics 2024年第5期10卷 1101-1108页

作者： Jie Song Peng Luo Hailong sun Hezhang Li chao Wang Yi Niu jing Jiang Clean Energy Materials and Engineering Center State Key Laboratory of Electronic Thin Films and Integrated DevicesSchool of Electronic Science and EngineeringUniversity of Electronic Science and Technology of ChinaChengdu611731China The State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing100084China

Thermoelectric materials are competitive candidates for special cooling ***_(3)Sb_(2)-based materials consisting of inexpensive ingredients have profound thermoelectric *** present,alloying with Mg_(3)Bi_(2) is the most effective approach to optimize the thermoelectric properties of Mg_(3)Sb_(2)-based ***,the extremely low abundance of bismuth in the crust contradicts its economic *** this work,the ZrO_(2) micro-particles were separated into the Mg_(3.2)Sb_(1.99)Te_(0.01).The doping effect of Zr atoms at Mg sites increased the electrical conductivity,and the combined secondary phase lowered the lattice thermal *** acceptable degradation in the Seebeck coefficient,the sample combined with 5%(in mass)ZrO_(2) exhibited a dimensionless figure of merit(zT)of 0.49 and a power factor of 2.7 mW·m^(−1)·K^(−2) near room *** average zT in the range from 300 K to 500 K reached 0.8,on par with the Mg_(3)Sb_(2) single bond Mg_(3)Bi_(2) ***,the compressive and bending strengths reach 669 MPa and 269 MPa,respectively,far superior to the common room-temperature *** secondary phase showed a surprising and uncostly promotion of the Mg_(3)Sb_(2)-based thermoelectric materials,impelling the realization of its commercial application.

关键词： Mg_(3)Sb_(2)-Mg_(3)Bi_(2)alloy Secondary phase Room-temperature thermoelectric properties Mechanical properties Inexpensive ingredients

Malvidin Mitigates Sepsis-induced Cardiac Injury by Modulating the TLR4-iNOS-COX-2 Inflammatory Pathway and the Bax/Bcl-2/Cyto-C Mitochondrial Apoptosis Pathway in a p38 MAPK-dependent Manner

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Biomedical and Environmental Sciences 2024年第2期37卷 221-227页

作者： ZHANG Wei YUAN Si Long QIANG jing chao HUANG He LI Da sun Ying ZHANG Hong Gang Department of Vascular Surgery The First People’s Hospital of LianyungangLianyungang 222005JiangsuChina Jiangsu Key Laboratory of Marine Pharmaceutical Compound Screening College of PharmacyJiangsu Ocean UniversityLianyungang 222005JiangsuChina Jinzhou Medical University postgraduate training base(Lianyungang First People’s Hospital) Lianyungang 222005JiangsuChina

In critical care medicine,sepsis is a dangerous systemic condition that is highly prevalent and is associated with high morbidity and mortality rates^([1]).The high mortality rate associated with sepsis is closely related to multi-organ dysfunction,with heart injury being particularly critical and considered the starting point of multi-organ injury^([2]).

关键词： mortality Apoptosis TLR4

High-precision analytical solutions for Earth coverage of constellation equipped with reentry glide vehicles

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Chinese Journal of Aeronautics 2024年第9期37卷 385-398页

作者： Ping MA Weibo sun Jie GAO Tao chao Control and Simulation Center Harbin Institute of TechnologyHarbin 150001China Beijing Institute of Spacecraft System Engineering Beijing 100094China

To efficiently and accurately design satellite constellations equipped with Reentry Glide Vehicles(RGVs),new analytical solutions are developed for calculating their coverage ***,a new coverage model is established by approximating the Reentry Reachable Domain(RRD).However,the computation of real-time relative distances between satellites and targets,which is essential for coverage analysis based on this model,imposes a significant compu-tational *** address this challenge,a coverage analysis method based on two-dimensional map theory is *** method represents the coverage conditions of a target as a fixed area on a two-dimensional map and transforms the satellite trajectory into a series of parallel *** determining the intersection points between these lines and the area boundaries,the coverage ana-lytical solutions for a target point are *** this basis,coverage theorems are presented for rapid calculation of the constellation coverage performance for an *** results demon-strate the effectiveness and high precision of the proposed analytical solutions.

关键词： Constellation Analytical solutions Reentry glide vehicle Reentry reachable domain Two-dimensional map

Recombinant angiopoietin-like protein 4 attenuates intestinal barrier structure and function injury after ischemia/reperfusion

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World Journal of Gastroenterology 2021年第32期27卷 5404-5423页

作者： Zi-Yi Wang Jian-Yu Lin Yang-Rong Feng De-Shun Liu Xu-Zi Zhao Tong Li Si-Yuan Li jing-chao sun Shu-Feng Li Wen-Yan Jia Hui-Rong jing Emergent Intensive Care Unit The Second Affiliated Hospital of Dalian Medical UniversityDalian 116023Liaoning ProvinceChina Department of Gastrointestinal Surgery Weihai Central HospitalWeihai 264200Shandong ProvinceChina Graduate College Shandong First Medical UniversityJinan 271000Shandong ProvinceChina Department of General Surgery The Second Affiliated Hospital of Dalian Medical UniversityDalian 116027Liaoning ProvinceChina Department of Pharmacology Dalian Medical UniversityDalian 116044Liaoning ProvinceChina Department of General Surgery Peking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100000China Department of General Surgery Qingdao Municipal HospitalQingdao UniversityQingdao 266071Shandong ProvinceChina Physiological Examination Center The Affiliated Hospital of Qingdao UniversityQingdao 266000Shandong ProvinceChina

BACKGROUND Intestinal barrier breakdown,a frequent complication of intestinal ischemiareperfusion(I/R)including dysfunction and the structure changes of the intestine,is characterized by a loss of tight junction and enhanced permeability of the intestinal barrier and increased *** develop effective and novel therapeutics is important for the improvement of outcome of patients with intestinal barrier *** human angiopoietin-like protein 4(rhANGPTL4)is reported to protect the blood-brain barrier when administered exogenously,and endogenous ANGPTL4 deficiency deteriorates radiationinduced intestinal *** To identify whether rhANGPTL4 may protect intestinal barrier breakdown induced by I/*** Intestinal I/R injury was elicited through clamping the superior mesenteric artery for 60 min followed by 240 min *** epithelial(Caco-2)cells and human umbilical vein endothelial cells were challenged by hypoxia/reoxygenation to mimic I/R in *** Indicators including fluorescein isothiocyanate-conjugated dextran(4 kilodaltons;FD-4)clearance,ratio of phosphorylated myosin light chain/total myosin light chain,myosin light chain kinase and loss of zonula occludens-1,claudin-2 and VE-cadherin were significantly increased after intestinal I/R or cell hypoxia/***4 treatment significantly reversed these indicators,which were associated with inhibiting the inflammatory and oxidative cascade,excessive activation of cellular autophagy and apoptosis and improvement of survival *** results were observed in vitro when cells were challenged by hypoxia/reoxygenation,whereas rhANGPTL4 reversed the indicators close to normal level in Caco-2 cells and human umbilical vein endothelial cells *** rhANGPTL4 can function as a protective agent against intestinal injury induced by intestinal I/R and improve survival via maintenance of intestinal barrier structure and functions.

关键词： Angiopoietin-like protein 4 Intestinal ischemia/reperfusion COVID-19 Myosin light chain kinase Intestinal barrier breakdown

Meiotic transcriptional reprogramming mediated by cell-cell communications in humans and mice revealed by scATACseq and scRNA-seq

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Zoological Research 2024年第3期45卷 601-616页

作者： Hai-Quan Wang Xiao-Long Wu jing Zhang Si-Ting Wang Yong-Juan Sang Kang Li chao-Fan Yang Fei sun chao-Jun Li State Key Laboratory of Reproductive Medicine and Offspring Health Center for Global HealthSchool of Public HealthNanjing Medical UniversityNanjingJiangsu 211166China Medical School Nanjing UniversityNanjingJiangsu 210093China Zhejiang University School of Medicine HangzhouZhejiang 310016China Department of Urology and Andrology Sir Run Run Shaw HospitalZhejiang University School of MedicineHangzhouZhejiang 310000China Model Animal Research Center of Medical School Nanjing UniversityNanjingNanjingJiangsu 210093China Liangzhu Laboratory Zhejiang UniversityHangzhouZhejiang 311121China

Meiosis is a highly complex process significantly influenced by transcriptional ***,studies on the mechanisms that govern transcriptomic changes during meiosis,especially in prophase I,are ***,we performed single-cell ATAC-seq of human testis tissues and observed reprogramming during the transition from zygotene to pachytene *** event,conserved in mice,involved the deactivation of genes associated with meiosis after reprogramming and the activation of those related to spermatogenesis before their functional ***,we identified 282 transcriptional regulators(TRs)that underwent activation or deactivation subsequent to this *** suggested that physical contact signals from Sertoli cells may regulate these TRs in spermatocytes,while secreted ENHO signals may alter metabolic patterns in these *** results further indicated that defective transcriptional reprogramming may be associated with non-obstructive azoospermia(NOA).This study revealed the importance of both physical contact and secreted signals between Sertoli cells and germ cells in meiotic progression.

关键词： Single-cell RNA-seq Single-cell ATAC-seq Spermatogenesis Meiosis Transcriptional reprogramming Cell-cell communication

Cascade electrolysis and thermocatalysis: a reliable system for upgrading C1 to C4 hydrocarbons

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Rare Metals 2024年第1期43卷 410-412页

作者： chao-Yue sun Wen Li Hai-Qing Wang Institute for Advanced Interdisciplinary Research(iAIR) College of Chemistry and Chemical EngineeringUniversity of JinanJinan 250022China

The carbon cycle is important for maintaining a stable climate and carbon balance on Earth. Renewable-electricitydriven upcycling of carbon dioxide (CO_(2)) into value-added multi-carbon molecules is a potentially sus... 详细信息

关键词： cycling hydrocarbons enable

OsPDR20 is an ABCG metal transporter regulating cadmium accumulation in rice

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Journal of Environmental Sciences 2024年第2期136卷 21-34页

作者： He Li chao Li Di sun Zhi Min Yang Department of Biochemistry and Molecular Biology College of Life SciencesNanjing Agricultural UniversityNanjing 210095China

Cadmium(Cd)is a non-essential toxic heavy metal,seriously posing high environmental risks to human *** genetic resources relevant to functional genes is important for understanding the metal absorption and accumulation in crops and bioremediation of Cd-polluted *** study investigated a functionally uncharacterized ATP binding cassette transporter G family(ABCG)gene encoding a Pleiotropic Drug Resistance 20(PDR20)type metal transporter which is localized to the plasma membrane of ***20 was transcriptionally expressed in almost all tissues and organs in lifespan and was strongly induced in roots and shoots of young rice under Cd *** expression of OsPDR20 in a yeast mutant ycf1 sensitive to Cd conferred cellular tolerance with less Cd *** of OsPDR20 by RNA interference(RNAi)moderately attenuated root/shoot elongation and biomass,with reduced chlorophylls in rice grown under hydroponic medium with 2 and 10μmol/L Cd,but led to more Cd accumulation.A field trial of rice grown in a realistic Cd-contaminated soil(0.40 mg/kg)showed that RNAi plants growth and development were also compromised compared to wild-type(WT),with smaller panicles and lower spikelet fertility but little effect on yield of ***,OsPDR20 suppression resulted in unexpectedly higher levels of Cd accumulation in rice straw including lower leaves and culm and *** results suggest that OsPDR20 is actively involved in Cd accumulation and homeostasis in rice *** increased Cd accumulation in the RNAi plants has the potential application in phytoremediation of Cd-polluted wetland soils.

关键词： Rice ABCG transporter Cadmium accumulation Phytoremediation

Mechanics and physics under supergravity conditions

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Acta Mechanica Sinica 2024年第6期40卷 1-2页

作者： chaofeng Lü chao sun Shengqiang Cai Faculty of Mechanical Engineering and Mechanics Ningbo UniversityNingbo 315211China New Cornerstone Science Laboratory Center for Combustion EnergyDepartment of Energy and Power EngineeringTsinghua UniversityBeijing 100084China Department of Mechanical and Aerospace Engineering University of CaliforniaSan DiegoLa Jolla CA 92093USA

"Supergravity"refers to the conditions where the effective gravity is greater than that of *** conditions are generally relevant to stellar evolution,geophysical movement,astrophysical flows,and *** also frequently occur in various engineering scenarios involving acceleration,such as the launch of space shuttles,operation of rotor engines,impacts and explosions,chemical separation processes,and overloaded testing *** is already demonstrated in physiological experiments that living organisms of animals or plants could be damaged,either temporarily or permanently,when subjected to *** create supergravity conditions for scientific research on the Earth,centrifugal equipment or rapidly rotating devices are omnipresent in various fields,such as aerospace engineering,geophysical science,chemical and biomedical engineering,nuclear engineering,rotating flows,and physical modeling tests.

关键词： geophysical Earth stellar