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Ultrasound blood flow characteristics changes in fetal umbilical artery thrombosis:A retrospective analysis

World Journal of Clinical Cases 2024年第2期12卷 240-248页

作者： Si-Jie hong Li-Wei hong Xiao-Qin he Xiao-hong Zhong Department of Ultrasound Women and Children's HospitalSchool of MedicineXiamen UniversityXiamen 361000Fujian ProvinceChina Ministry of Science and Education Women and Children's HospitalSchool of MedicineXiamen UniversityXiamen 361000Fujian ProvinceChina

BACKGROUND Umbilical artery thrombosis(UAT)is extremely uncommon and leads to adverse perinatal *** of blood in pregnant women is suspected to be an important risk for *** is an effective way to detect *** mother can monitor her own fetal health using ultrasound,which enables her to take preventative action in case of *** To investigate ultrasonic blood signal after UAT in the umbilical artery,and evaluate the relationship between hypercoagulability and *** We described a case of a newly formed UAT with markedly altered ultrasonic indices of umbilical artery blood flow,and retrospectively studied it with 18 UAT patients confirmed by histopathology from October 2019 and March 2023 in Xiamen Women and Children's ***’information was collected from medical archives,including maternal clinical data,neonatal outcomes,pathological findings and ultrasonic indices of umbilical artery blood flow,such as systolic-diastolic duration ratio(S/D),resistance index(RI),pulsatility index(PI)and peak systolic velocity(PSV).Ultrasound and coagulation indices were analyzed with matched samples t-test and Wilcoxon rank sum test using the statistical packages in R(version 4.2.1)including car(version 3.1-0)and stats(version 4.2.1),and visualized by ggplot2 package(version 3.3.6).RESULTS A patient with normal findings in second and third-trimester routine ultrasound scan developed UAT with severe changes in ultrasonic indices of umbilical artery blood flow(within 2.5th of reference ranges)in a short period of *** analysis of umbilical artery blood flow ultrasound indices for 19 patients with UAT showed that the decrease in S/D,RI,and PI and increase of PSV during the disease process was greater than that of *** 18 patients delivered in our hospital showed characteristic manifestations of UAT on histological examination after delivery,most of which(16/18)showed umbilical cord abnormalities,with 1

关键词： Umbilical artery thrombosis Obstetric ultrasonography Peak systolic velocity Hypercoagulation Umbilical cord abnormalities Fetus

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Experimental and first-principles calculation of TiN growth mechanism on CeAlO_(3) surface in steel

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Journal of Iron and Steel Research International 2024年第2期31卷 452-463页

作者： Fei-hu he Jun Peng Fang Zhang Yong-bin Wang hong-tao Chang School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou014010Inner MongoliaChina

Regular TiN is harmful to the toughness of steel,and its shape and size need to be *** the behavior of TiN precipitation on CeAlO_(3) surfaces is critical for controlling the morphology and formation process of CeAlO_(3)–TiN composite inclusions in the *** results showed that TiN had a square morphology on the CeAlO3 surface,and electron backscatter diffraction phase identification results revealed the orientation relationship between CeAlO_(3) and TiN as follows:(001)_(CeAlO_(3))//(110)_(TiN),(100)_(CeAlO_(3))/(001)_(TiN),and[010]_(CeAlO_(3))/[110]_(TiN).The CeAlO3 crystal structure was studied using the first-principles calculation method,and the adsorption and growth process of TiN on the CeAlO_(3) surface were investigated from the atomic *** calculation results indicate that there is no metallic bonding present in the CeAlO_(3) *** the low-index crystal planes of CeAlO_(3),the(110)planes terminated with O and CeAlO have the highest and lowest surface energies,respectively,with values of 0.373 and 0.051 eV/Å^(2).On the high surface energy plane of CeAlO_(3),the TiN atomic permutation structure is consistent with the arrangement of Ti and N atoms in TiN(100)or(110).For the low surface energy plane of CeAlO_(3),the Ti and N atoms are arranged in a ring-like structure.

关键词： CeAlO_(3)-TiN inclusion Orientation relationship Crystal structure First principle Surface energy

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Carbon allocation in Picea jezoensis:Adaptation strategies of a non-treeline species at its upper elevation limit

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Forest Ecosystems 2024年第3期11卷 347-357页

作者： Renkai Dong Na Li Mai-he Li Yu Cong Haibo Du Decai Gao hong S.he Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains Ministry of EducationSchool of Geographical SciencesNortheast Normal UniversityChangchun130024China School of Natural Resources University of MissouriColumbiaMO65211USA Swiss Federal Institute for Forest Snow and Landscape Research WSL8903BirmensdorfSwitzerland Northeast Institute of Geography and Agricultural Ecology Chinese Academy of SciencesChangchun130102China School of Life Science Hebei UniversityBaoding071002China

Understanding the physiological adaptations of non-treeline trees to environmental stress is important to understand future shifts in species composition and distribution of current treeline *** aim of the present study was to elucidate the mechanisms of the formation of the upper elevation limit of non-treeline tree species,Picea jezoensis,and the carbon allocation strategies of the species on Changbai *** employed the^(13)C in situ pulse labeling technique to trace the distribution of photosynthetically assimilated carbon in Picea jezoensis at different elevational positions(tree species at its upper elevation limit(TSAUE,1,700 m a.s.l.)under treeline ecotone;tree species at a lower elevation position(TSALE,1,400 m a.s.l.).We analyzed^(13)C and the non-structural carbohydrate(NSC)concentrations in various tissues following *** findings revealed a significant shift in carbon allocation in TSAUE compared to *** was a pronounced increase inδ^(13)C allocation to belowground components(roots,soil,soil respiration)in TSAUE compared to ***,the C flow rate within the plant-soil-atmosphere system was faster,and the C residence time in the plant was shorter in *** trends indicate enhanced C sink activity in belowground tissues in TSAUE,with newly assimilated C being preferentially directed there,suggesting a more conservative C allocation strategy by *** at higher elevations under harsher *** a strategy,prioritizing C storage in roots,likely aids in withstanding winter cold stress at the expense of aboveground growth during the growing season,leading to reduced growth of TSAUE compared to *** results of the present study shed light on the adaptive mechanisms governing the upper elevation limits of non-treeline trees,and enhances our understanding of how non-treeline species might respond to ongoing climate change.

关键词： ^(13)C pulse labeling Carbon distribution Non-structural carbohydrates(NSC) Non-treeline species Sink activity Stressful environments Upper elevation limit

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Surface-induced Microstructure and Performance Changes in P3HT Ultrathin Films

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Chinese Journal of Polymer Science 2024年第6期42卷 805-814页

作者： hong-Tao Shan Jia-Xin he Bing-Yan Zhu Xue-Ting Cao Ying-Ying Yan Jian-Jun Zhou hong Huo Beijing Key Laboratory of Energy Conversion and Storage Materials College of ChemistryBeijing Normal UniversityBeijing100875China

In this work,poly(3-hexylthiophene)(P3HT)ultrathin films(P3HT-T)were prepared by spin-coating a dilute P3HT solution(in a toluene:o-dichlorobenzene(Tol:ODCB)blend with a volume ratio of 80:20)with ultrasonication and the addition of the nucleating agent bicycle[2.2.1]heptane-2,3-dicarboxylic acid disodium salt(HPN-68L)on glass,Si wafers and indium tin oxide(ITO)*** electrical and mechanical properties of the P3HT-T ultrathin films were investigated,and it was found that the conductivity and crack onset strain(COS)were simultaneously improved in comparison with those of the corresponding pristine P3HT film(P3HT-0,without ultrasonication and nucleating agent)on the same substrate,regardless of what substrate was ***,the conductivity of P3HT-T ultrathin films on different substrates was similar(varying from 3.7 S·cm^(-1)to 4.4 S·cm^(-1)),yet the COS increased from 97%to 138%by varying the substrate from a Si wafer to *** grazing-incidence wide-angle X-ray diffraction(GIXRD),UV-visible(UV-Vis)spectroscopy and atomic force microscopy(AFM),we found that the solid order and crystallinity of the P3HT-T ultrathin film on the Si wafer are highest,followed by those on glass,and much lower on ***,the surface energy and roughness of three substrates were investigated,and it was found that the polar component of the surface energyγp plays a critical role in determining the crystalline microstructures of P3HT ultrathin films on different *** work indicates that the P3HT ultrathin film can obviously improve the stretchability and simultaneously retain similar electrical performance when a suitable substrate is *** findings offer a new direction for research on stretchable CP ultrathin films to facilitate future practical applications.

关键词： P3HT ultrathin film Substrate Crystalline microstructures Polar component of the surface energy Electrical and stretchable performances

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Experimental research on the launching system of auxiliary charge with filter cartridge structure

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Defence Technology（防务技术） 2024年第1期31卷 41-48页

作者： Zi-Jun Chen Ze he hong-Hao Ma Lu-Qing Wang Zhao-Wu Shen CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsUniversity of Science and Technology of ChinaHefeiAnhui230027PR China State Key Laboratory of Fire Science University of Science and Technology of ChinaHefeiAnhui230026PR China

A launching system with a filter cartridge structure was proposed to improve the muzzle velocity of the *** combustion chamber of the launching system is divided into two fixed chambers,one is located in the breech chamber,and the other is arranged in the *** breech chamber charge was ignited first,and the charges in the auxiliary chambers were ignited by the high-temperature,highpressure combustible gas trailing the *** this way,the combustible gas in the auxiliary chambers could compensate for the pressure drop caused by the movement of the *** proposed device features the advantage of launching a projectile with high muzzle velocity without exceeding the maximum pressure in the *** order to obtain some internal ballistic characteristics of the launch system,some critical structure,such as the length of the filter cartridge auxiliary charge,the combustion degree of the propellant in the chamber,and the length of the barrel,are *** experimental results show that with the increased auxiliary charge length,a pressure plateau or even a secondary peak pressure can be formed,which is less than the peak *** projectile velocity increased by 23.57%,14.64%,and 7.65%when the diaphragm thickness was 0 mm,1 mm,and2 mm,*** muzzle velocity of the projectile can be increased by 13.42%by increasing the length of the *** the same charge condition,with the increase of barrel length,the energy utilization rate of propellant increases by 28.64%.

关键词： Interior ballistics Charge structures Launch system Charge design

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Constructing extrinsic oxygen vacancy on the surface of photocatalyst as CO_(2)and electrons reservoirs to improve photocatalytic CO_(2)reduction activity

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Journal of Environmental Sciences 2024年第6期140卷 37-45页

作者： Zaiyong Jiang Hao Li Zhimin Yuan Zheng Wang Maohong Fan Wenkang Miao hong he State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China School of Chemistry&Chemical Engineering and Environmental Engineering Weifang UniversityWeifangShandong 261061China Departments of Chemical and Petroleum Engineering University of WyomingLaramieWY 82071USA Materials Genome Institute Shanghai UniversityShanghai 200444China

Constructing own oxygen vacancies in the photocatalysts is a very promising method to improve their photocatalytic CO_(2)reduction ***,some catalysts have excellent stabilities,making it difficult for them to construct their own oxygen *** simplify the above difficulty of stable photocatalysts,constructing extrinsic oxygen vacancies on their surface as a novel idea is ***,a stable TiO_(2)nanosheet is chosen as a research object,we uniformly deposited BiOCl quantum dots on their surface via a simple adsorption-deposition *** is found that BiOCl quantum dots are able to simultaneously self-transform into defective BiOCl with many oxygen vacancies when the photocatalyst is performed photocatalytic CO_(2)*** extrinsic oxygen vacancies can act as“CO_(2)and photo-generated electrons reservoirs”to improve CO_(2)capture and accelerate the separation of photogenerated electrons and *** the above reasons,the modified TiO_(2)showed obvious enhancement of photocatalytic CO_(2)reduction compared to pristine TiO_(2)and *** work may open a new avenue to broaden the use of oxygen vacancies in the process of photocatalytic CO_(2)reduction.

关键词： Oxygen vacancy BiOCl Photocatalyst CO_(2)reduction TiO_(2)

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R2R3-type Lo MYB21 affects jasmonate-regulated development and dehiscence of anthers in lily(Lilium oriental hybrids)

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Horticultural Plant Journal 2024年第1期10卷 239-251页

作者： Zheng Tong Tingting Dong Qiuhua Li Rui Wang Junna he Bo hong Institute of Tropical Bioscience and Biotechnology Chinese Academy of Tropical Agricultural Sciences&Hainan Institute for Tropical Agricultural ResourcesHaikouHainan 571101China Beijing Key Laboratory of Development and Quality Control of Ornamental Crops Department of Ornamental HorticultureChina Agricultural UniversityBeijing 100193China Beijing Garden Expo Management Center Beijing 100072China

Lilies are widely cultivated for cut flowers,but their large anthers carry a considerable amount of colored pollen that is dispersed *** the molecular mechanism of anther development and dehiscence could help solve this ***21,encoding a putative R2R3v-myb avian myeloblastosis viral oncogene homolog(MYB)transcription factor,was identified from oriental lilies(Lilium‘Siberia’).Real-time quantitative PCR analysis showed that LoMYB21 was mainly expressed in the anther,filament and stigma and had high expression during the late stages of lily anther ***21 had transactivation activity and was located in the nucleus through yeast one-hybrid assays and transient expression in Nicotiana *** of LoMYB21 by virus-induced gene silencing(VIGS)in Lilium‘Siberia’led to anther indehiscence and reduced the expression of genes related to Jasmonate acid(JA)biosynthesis and signal *** of LoMYB21 in DEX::LoMYB21 transgenic Arabidopsis caused procumbent inflorescences that became infertile,accompanied by higher expression of JA biosynthetic and signaling *** results demonstrated that JA content and signaling were abnormal in silenced lily and transgenic LoMYB21 Arabidopsis,which affected anther *** study indicated that LoMYB21 could regulate lily anther dehiscence through JA biosynthesis and signaling during the late stages of anther development.

关键词： Lilium LoMYB21 Anther dehiscence Jasmonate acid

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Effect of Hyperconjugation on Photovoltaic Performance in Pseduo-2D Perylene Diimide Derivatives

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Chinese Journal of Chemistry 2024年第7期42卷 725-730页

作者： Zhilong he Yuwen hong Guangyu Li Tong Shan Yi Zhang hongliang Zhong Schoolof Chemistry and Chemical Engineering Shanghai Key Lab of Electrical Insulation and Thermal AgingShanghai Jiao Tong UniversityShanghai200230China Shanghai Institute of Organic Chemistry Chinese Academy of SciencesShanghai 200032China Shenzhen Research Institute Shanghai Jiao Tong UniversityShenzhenGuangdong 518057China

Theπ-πinteraction is acknowledged as the predominant factor to determine the molecular packing in organic photovoltaic materials,while other non-covalent intermolecular interactions especially theσ-πhyperconjugation are often ***,a perylene diimide(PDI)derivative named FIDT-PDI is designed and synthesized to shed light into the effect of hyperconjugation on the molecular packing and further the photovoltaic *** NMR and 2D NOE NMR demonstrate the formation of intermolecularσ-πhyperconjugation between the C—H bond of the PDI moiety in one molecule and the phenyl sidechain in another molecule of *** from theσ-πhyperconjugation,FIDT-PDI with twisted backbone reversely exhibits more ordered packing and stronger crystallinity compared with another PDI derivative FIDTT-PDI which has better planarity,consequently achieving superior PCE and higher carrier *** contribution is the first paradigm to unravel the structure-property relationship betweenσ-πhyper-conjugation of conjugated materials and corresponding photovoltaic performance.

关键词： Hyperconjugation Weak intermolecular interactions Conformation Organic solar cells Nonfullerene acceptor Perylene diimide

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MADRL-based UAV swarm non-cooperative game under incomplete information

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Chinese Journal of Aeronautics 2024年第6期37卷 293-306页

作者： Ershen WANG Fan LIU Chen hong Jing GUO Lin ZHAO Jian XUE Ning he School of Electronic and Information Engineering Shenyang Aerospace UniversityShenyang 110136China College of Robotics Beijing Union UniversityBeijing 100101China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China College of Smart City Beijing Union UniversityBeijing 100101China

Unmanned Aerial Vehicles(UAVs)play increasing important role in modern *** this paper,considering the incomplete observation information of individual UAV in complex combat environment,we put forward an UAV swarm non-cooperative game model based on Multi-Agent Deep Reinforcement Learning(MADRL),where the state space and action space are constructed to adapt the real features of UAV swarm air-to-air *** multi-agent particle environment is employed to generate an UAV combat scene with continuous observation *** recently popular MADRL methods are compared extensively in the UAV swarm noncooperative game model,the results indicate that the performance of Multi-Agent Soft Actor-Critic(MASAC)is better than that of other MADRL methods by a large *** swarm employing MASAC can learn more effective policies,and obtain much higher hit rate and win *** under different swarm sizes and UAV physical parameters are also performed,which implies that MASAC owns a well generalization ***,the practicability and convergence of MASAC are addressed by investigating the loss value of Q-value networks with respect to individual UAV,the results demonstrate that MASAC is of good practicability and the Nash equilibrium of the UAV swarm non-cooperative game under incomplete information can be reached.

关键词： UAV swarm Reinforcement learning Deep learning Multi-agent Non-cooperative game Nash equilibrium

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Impact of surface-reflected seismic waves on the seismic isolation performance of circular tunnel isolation layers

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Journal of Mountain Science 2024年第3期21卷 901-917页

作者： LU Jiahui LUO Junjie HUANG Xiangyun hong Junliang he YanXin ZHOU Fulin Department of Civil Engineering Xi’an University of Architecture and Technology(XAUAT)Xi’an 710055China Earthquake Engineering Research and Test Centre Guangzhou UniversityGuangzhou 510623China Guangdong Provincial Key Laboratory of Earthquake Engineering and Applied Technology Guangzhou UniversityGuangzhou 510623China Key Laboratory of Earthquake Resistance Earthquake Mitigation and Structural SafetyMinistry of EducationGuangzhou UniversityGuangzhou 510623China

Seismic isolation is an effective strategy to mitigate the risk of seismic damage in ***,the impact of surface-reflected seismic waves on the effectiveness of tunnel isolation layers remains under *** this study,we employ the wave function expansion method to provide analytical solutions for the dynamic responses of linings in an elastic half-space and an infinite elastic *** comparing the results of the two models,we investigate the seismic isolation effect of tunnel isolation layers induced by reflected seismic *** findings reveal significant differences in the dynamic responses of the lining in the elastic half-space and the infinitely elastic ***,the dynamic stress concentration factor(DSCF)of the lining in the elastic half-space exhibits periodic fluctuations,influenced by the incident wave frequency and tunnel depth,while the DSCF in the infinitely elastic space remain ***,the seismic isolation application of the tunnel isolation layer is found to be less affected by surface-reflected seismic *** results provide valuable insights for the design and assessment of the seismic isolation effect of tunnel isolation layers.

关键词： Circular tunnel seismic isolation Surface reflection Response of liners Wave-function expansion method

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