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Anomalous Optical and Electronic Properties of CaTiO3 Perovskites

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Communications in Theoretical Physics 2007年第3X期48卷 563-570页

作者： LIU Hui-ping DUAN yi-Feng yi Lin Department of Physics and State Key Laboratory of Laser Technology Huazhong University of Science and TechnologyWuhan 430074 China

With the help of the first-prlnciples full potential linearized augmented plane wave method, absorption coefficients, reflect/vity, dielectric behavior and electronic properties, including electronic energy bands, density of states and charge density distributions, are studied for the tetragonal and cubic CaTiO3. By considering the thermal expansion effects, an approximate method is proposed for the study of the stability of ground state and a tendency of phase transition, based on the minimum free energy principle. Subsequently, numerical calculations are carried out by using the first-principles perturbation method. We demonstrate that the high-temperature phase is cubic. It is shown that optical spectra in tetragonal phase exhibit single-peak feature and differ from multi-peak character in cubic. We find that strong orbital hybridization results in the co-valent bonds between Ti 3d and O 2p electrons and forms two-type dipoles （Ti-Ol and Ti-02） in tetragonal, while the Ti-O dipoles are identical in cubic. It is argued that crystal structure determines the dipole distributions and leads to some electron states among which the dipole-dipole transit/on forbidden is a key, causing such anomalous optical phenomena with the insulator characteristics. The predicted charge density distribution and the tendency of phase transition from tetragonal to cubic are in good agreement with experimental observations.

关键词： first-principles calculations CaTiO3 perovskites optical and electronic properties

Analog spatiotemporal feature extraction for cognitive radio-frequency sensing with integrated photonics

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Light(Science & Applications) 2024年第3期13卷 478-487页

作者： Shaofu Xu Binshuo Liu Sicheng yi Jing Wang Weiwen zou State Key Laboratory of Advanced Optical Communication Systems and Networks Intelligent Microwave Lightwave Integration Innovation Center(imLic)Department of Electronic EngineeringShanghai Jiao Tong UniversityShanghaiChina

Analog feature extraction(AFE)is an appealing strategy for low-latency and efficient cognitive sensing systems since key features are much sparser than the Nyquist-sampled ***,applying AFE to broadband radio-frequency(RF)scenarios is challenging due to the bandwidth and programmability bottlenecks of analog electronic ***,we introduce a photonics-based scheme that extracts spatiotemporal features from broadband RF signals in the analog *** feature extractor structure inspired by convolutional neural networks is implemented on integrated photonic circuits to process RF signals from multiple antennas,extracting valid features from both temporal and spatial *** of the tunability of the photonic devices,the photonic spatiotemporal feature extractor is trainable,which enhances the validity of the extracted ***,a digital-analog-hybrid transfer learning method is proposed for the effective and low-cost training of the photonic feature *** validate our scheme,we demonstrate a radar target recognition task with a 4-GHz instantaneous *** results indicate that the photonic analog feature extractor tackles broadband RF signals and reduces the sampling rate of analog-to-digital converters to 1/4 of the Nyquist sampling while maintaining a high target recognition accuracy of 97.5%.Our scheme offers a promising path for exploiting the AFE strategy in the realm of cognitive RF sensing,with the potential to contribute to the efficient signal processing involved in applications such as autonomous driving,robotics,and smart factories.

关键词： scheme driving smart

Interaction between ozone and paternal smoking on fetal congenital heart defects among pregnant women at high risk a multicenter maternal-fetal medicine study

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World Journal of Pediatrics 2024年第6期20卷 621-632页

作者： Huan Wang Yan-ping Ruan Sheng Ma Ya-Qi Wang Xiao-Yu Wan yi-Hua He Jing Li Zhi-Yong zou Institute of Child and Adolescent Health School of Public HealthNational Health Commission Key Laboratory of Reproductive HealthPeking UniversityNo.38 Xueyuan RdHaidian DistrictBeijing 100191China Echocardiography Medical Center Beijing Anzhen Hospital.Capital Medical UniversityMaternal-Fetal Medicine center in Fetal Heart DiseaseBeijing Anzhen HospitalNo.2 Anzhen RdChaoyang DistrictBeijing 100029China

Background Evidence remains limited on the association between maternal ozone(O,)exposure and congenital heart defects(CHDs)in offspring,and few studies have investigated the interaction and modification of paternal smoking on this *** Using a sample including pregnant women at high risk of fetal CHD(with metabolic disease,first-trimester viral infection,family history of CHD,etc.)from a maternal-fetal medicine study covering 1313 referral hospitals in China during 2013-2021,we examined the associations between maternal O_(3)exposure during 3-8 weeks of gestational age and fetal CHD in offspring and investigated the interaction and modification of paternal smoking on this *** was diagnosed by fetal echocardiograms,maximum daily 8-hour average O,exposure data at a 10 km×10 km spatial resolution came from the Tracking Air Pollution in China dataset,and paternal smoking was collected using *** regression models were used to estimate adjusted odds ratios(ORs)and 95%confidence intervals(CIs).Results Among 27,834 pregnant women at high risk of fetal CHD,17.4%of fetuses were diagnosed with *** 10μg/m^(3)increase in maternal O_(3)exposure was associated with a 17%increased risk of CHD in offspring(OR=1.17,95%CI=1.14-1.20).Compared with paternal nonsmoking and maternal low O_(3)exposure,the ORs(95%CI)of CHD for smoking and low O_(3)exposure,nonsmoking and high O_(3)exposure,and smoking and high O_(3)exposure were 1.25(1.08-1.45),1.81(1.56-2.08),and 2.23(1.84-2.71),*** smoking cessation seemingly mitigated the increased risk of *** Maternal O_(3)exposure and paternal smoking were interactively associated with an increased risk of fetal CHD in offspring,which calls for effective measures to decrease maternal exposure to O_(3)pollution and secondhand smoke for CHDprevention.

关键词： Congenital heart defects Fetal heart development Ozone exposure Tobacco smoking

Supramolecular polymer-based gel fracturing fluid with a double network applied in ultra-deep hydraulic fracturing

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Petroleum Science 2024年第3期21卷 1875-1888页

作者： Yong-ping Huang Yong Hu Chang-Long Liu yi-Ning Wu Chen-Wei zou Li-Yuan Zhang Ming-Wei Zhao Cai-Li Dai School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongPR China Shandong Key Laboratory of Oilfield Chemistry China University of Petroleum(East China)Qingdao 266580ShandongPR China SINOPEC Petroleum Exploration and Production Research Institute Beijing102206PR China CNOOC China Co Ltd Tianjin BranchTianjin300459PR China

A gel based on polyacrylamide,exhibiting delayed crosslinking characteristics,emerges as the preferred solution for mitigating degradation under conditions of high temperature and extended shear in ultralong *** viscosity/viscoelasticity of the fracturing fluid was required to maintain excellent proppant suspension properties before *** into account both the cost and the potential damage to reservoirs,polymers with lower concentrations and molecular weights are generally *** this work,the supramolecular action was integrated into the polymer,resulting in significant increases in the viscosity and viscoelasticity of the synthesized supramolecular polymer *** double network gel,which is formed by the combination of the supramolecular polymer system and a small quantity of Zr-crosslinker,effectively resists temperature while minimizing permeability damage to the *** results indicate that the supramolecular polymer system with a molecular weight of(268—380)×10^(4)g/mol can achieve the same viscosity and viscoelasticity at 0.4 wt%due to the supramolecular interaction between polymers,compared to the 0.6 wt%traditional polymer(hydrolyzed polyacrylamide,molecular weight of 1078×10^(4)g/mol).The supramolecular polymer system possessed excellent proppant suspension properties with a 0.55 cm/min sedimentation rate at 0.4 wt%,whereas the0.6 wt%traditional polymer had a rate of 0.57 cm/*** comparison to the traditional gel with a Zrcrosslinker concentration of 0.6 wt%and an elastic modulus of 7.77 Pa,the double network gel with a higher elastic modulus(9.00 Pa)could be formed only at 0.1 wt%Zr-crosslinker,which greatly reduced the amount of residue of the fluid after *** viscosity of the double network gel was66 m Pa s after 2 h shearing,whereas the traditional gel only reached 27 m Pa s.

关键词： Ultra-deep reservoir Gel fracturing fluid Double network Supramolecular polymer system Proppant suspension property

Functional expression of CD95/Fas Antigen and Bcl-2 on Cord blood Hematopoietic Progenitor Cells

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Journal of Huazhong University of Science and Technology(Medical Sciences) 2002年第1期22卷 24-27页

作者： MA Yanping(马艳萍) zou ping (邹萍) Department of Hematology Xiehe Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 Department of Hematology Xiehe Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430030

The cell surface expression and functional status of the CD95/Fas antigen on primitive hematopoietic progenitors isolated from human cord blood (CB) were studied. The CD34 + cells freshly isolated from CB displayed low CD95 expression. The combinations of cytokines such as SCF+FL could up regulate the expression of CD95 in vitro culture and tumor necrosis factor α (TNF α) and interon γ (IFN γ) further increased the CD95 expression induced by positive cytokines. The functional status of CD95 mediated apoptosis were analyzed by incubation of CD34 +CB cells in the presence of anti CD95 monoclonal antibodies (McAbs). The effects of anti CD95 McAbs were measured by viable cell counting, flow cytometry, LTIC and CFU C assays. A decrease of viable cells, CFU C and LTIC numbers were observed in the presence of anti CD95 McAbs and TNF α or IFN γ. However, growth factor deprivation or the early acting cytokine such as SCF and FL cross linking to CD95 caused low apoptosis of CD34 + cells. The correlation of increased intracytoplasmic levels of bcl 2 and the presence of CD95 on fresh CB CD34 + cells suggested that bcl 2 might be involved in protecting against CD95 mediated apoptosis of CB CD34 + cells.

关键词： CD95/Fas Bcl 2 expression cord blood CD34 + cells

Berberine retarded the growth of gastric cancer xenograft tumors by targeting hepatocyte nuclear factor 4α

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World Journal of Gastrointestinal Oncology 2022年第4期14卷 842-857页

作者： Ling-Li Li Ze Peng Qian Hu Li-Jun Xu Xin zou Dong-Mei Huang ping yi Department of Integrated Traditional Chinese and Western Medicine Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430045Hubei ProvinceChina Department of Integrated Traditional Chinese and Western Medicine West China Hospital of Sichuan UniversityChengdu 610041Sichuan ProvinceChina

BACKGROUND Gastric cancer is the third deadliest cancer in the world and ranks second in incidence and mortality of cancers in *** advances in prevention,diagnosis,and therapy,the absolute number of cases is increasing every year due to aging and the growth of high-risk populations,and gastric cancer is still a leading cause of cancer-related *** cancer is a consequence of the complex interaction of microbial agents,with environmental and host factors,resulting in the dysregulation of multiple oncogenic and tumor-suppressing signaling *** efforts have been made to investigate in detail the genomic and epigenomic heterogeneity of this disease,resulting in the identification of new specific and sensitive predictive and prognostic ***,a monoclonal antibody against the HER2 receptor,is approved in the first-line treatment of patients with HER2+tumors,which accounts for 13%-23%of the gastric cancer ***,a monoclonal antibody against VEGFR2,is currently recommended in patients progressing after first-line *** clinical trials have also tested novel agents for advanced gastric cancer but mostly with dis-appointing results,such as anti-EGFR and anti-MET monoclonal ***,it is still of great significance to screen specific molecular targets for gastric cancer and drugs directed against the molecular *** To investigate the effect and mechanism of berberine against tumor growth in gastric cancer xenograft models and to explore the role of hepatocyte nuclear factor 4α(HNF4α)-WNT5a/β-catenin pathways played in the antitumor effects of *** MGC803 and SGC7901 subcutaneous xenograft models were *** control group was intragastrically administrated with normal saline,and the berberine group was administrated intragastrically with 100 mg/kg/d *** body weight of nude mice during the experiment was measured to assess whether berberine has any adver

关键词： Berberine Gastric cancer Xenograft models Hepatocyte nuclear factor 4α WNT5a

Synthesis and Molecular Structure of Acetic Acid-3,5-diacetoxy-2-acetoxymethyl-6-(4-quinoxalin-2-yl-phenoxy)-tetrahydro-pyran-4-yl-ester

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Chinese Journal of Structural Chemistry 2006年第8期25卷 1014-1018页

作者： WEI Hui-Qin ZENG Run-Sheng WU Gui-ping WANG Bao-An zou Jian-ping Key Laboratory of Organic Synthesis of Jiangsu Province College ofChemistry and Chemical Engineering Suzhou University Suzhou 215123 China

The title compound, acetic acid-3,5-diacetoxy-2-acetoxymethyl-6-（4-quinoxalin- 2-yl-phenoxy）-tetrahydro-pyran-4-yl-ester 8 （C28H28N2O10, Mr = 552.54）, has been synthesized and its crystal structure was determined by X-ray diffraction analysis. It crystallizes in monoclinic, space group P21, a = 10.060（8）, b = 5.648（4）, c = 24.11（2）A, β = 91.078（10）°, Z = 2, V= 1369.9（19）A^3, Dc = 1.339 g/cm^3,μ（MoKa） = 1.03 cm^-1, F（000） = 580.00, T =. 193.1 Kx-9 θmax = 25.03, （△/σ）max = 0.0000, Flack = -0.0（24）, the final R = 0.0680 and wR = 0.140 （w = 1/[0.0016Fo^2 ＋ 1.00000（Fo^2）]/（4Fo^2）） for 3126 observed reflections （1 〉 20（/））. The pyranoid ring adopts chair conformation in the sugar moiety, and all of the acetyl groups are in the e bond of the pyranoid ring, so the sugar moiety is very stable.

关键词： acetic acid-3 5-diacetoxy-2-acetoxymethyl-6-(4-quinoxalin-2-yl-phenoxy)-tetrahydro-pyran-4-yl-ester synthesis crystal structure

Improved Algorithms for Removing Isolated Non-Meteorological Echoes and Ground Clutters in CINRAD

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Journal of Meteorological Research 2018年第4期32卷 584-597页

作者： Haibo zou Shuwen ZHANG Xudong LIANG Xueting yi College of Atmosphere Sciences Lanzhou UniversityLanzhou 730000 State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081 Meteorological Disaster Emergency Warning Center of Jiangxi Province Nanchang 330046

Using China New Generation Weather Radar （CINRAD） level-Ⅱ data, the original algorithms for removing isol-ated non-meteorological echoes and ground clutters in radar data, which have been applied to Weather Surveillance Radar-1988 Doppler （WSR-88D） in the USA and Severe Weather Automatic Nowcast （SWAN） system in China, are modified and improved. To remove isolated non-meteorological echoes, the new algorithm introduces a constraint parameter （Po） to distinguish whether a window of 5 x 5 points is isolated as external echoes. A statistical analysis of 150 radar scans （5 cases, with each case comprising 30 scans） under three different echo types （small-scale convec-tion, typhoon, and large-scale synoptic system） shows that the constraint parameter Po ≤ 0.167 is suitable for remov- ing isolated non-meteorological echoes while preserving the edge of meteorological echoes. A new parameter, NDZ, which promotes the ability of the algorithm to identify the ground clutters appearing at two adjacent elevation angles, is constructed based on the vertical continuity of reflectivity. These improved algorithms are tested for four cases （three cases of isolated non-meteorological echoes and one case of ground clutters）. Based on the statistics of 232 volume scans of radar data （on a temporal resolution of 1 h） measured at Nanchang station from 0000 UTC 5 to 1600 UTC 14 March 2015, it is found that the improved algorithms not only eliminate most （over 95% under clear-sky conditions） of the isolated non-meteorological echoes and ground clutters （including those appearing at two adjacent elevation angles）, but also well preserve the structure of meteorological echoes （storms）.

关键词： radar isolated non-meteorological echoes ground clutter quality control

Power outage and environmental justice in Winter Storm Uri: an analytical workflow based on nighttime light remote sensing

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International Journal of Digital Earth 2023年第1期16卷 2259-2278页

作者： Jinwen Xu yi Qiang Heng Cai Lei zou GIS Center Florida International UniversityMiamiFLUSA School of Geosciences University of South FloridaTampaFLUSA Department of Geography Texas A&M UniversityCollege StationTXUSA

The intensity of extreme weather events has been increasing,posing a unique threat to society and highlighting the importance of our electrical power system,a key component in our *** severe weather events,quickly identifying power outage impact zones and affected communities is crucial for informed disaster ***,a lack of household-level power outage data impedes timely and precise *** address these challenges,we introduced an analytical workflow using NASA’s Black Marble daily nighttime light(NTL)images to detect power outages from the 2021 Winter Storm *** workflow includes adjustments to mitigate viewing angle and snow reflection *** outage is detected by comparing storm-time and baseline(normal condition)NTL images using an empirical adjusted *** outcomes of the workflow are 500-meter resolution power outage maps,which have the optimal correlation with real outage tracking data when NTL intensity is reduced by 26%.With the resultant power outage maps,we analyzed the relations between power outages and disadvantaged populations in 126 Texas counties and 4182 census tracts to evaluate environmental justice in the *** results show that Latino/Hispanic communities tend to suffer more from power outages at both the county and census tract levels.

关键词： Nighttime light disaster resilience natural disaster spatial analysis environmental justice power outage