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Genome editing in horticultural crops:augmenting trait development and stress resilience
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作者 Hamza Sohail Iqra Noor +4 位作者 Hammad Hussain Lili Zhang Xuewen Xu Xuehao Chen xiaodong yang 《Horticultural Plant Journal》 2026年第1期1-18,共18页
Horticultural crops are important for global nutrition,health,and economic security but are increasingly challenged by climate change and environmental stresses.The advent of CRISPR/Cas9(Clustered Regularly Interspace... Horticultural crops are important for global nutrition,health,and economic security but are increasingly challenged by climate change and environmental stresses.The advent of CRISPR/Cas9(Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR-Associated Protein 9)has revolutionized precision breeding by enabling targeted gene modifications that enhance yield,disease resistance,and stress tolerance.This review summarizes recent advancements in the application of CRISPR/Cas9 across fruit,vegetable,and ornamental crops,highlighting key achievements in enhancing crop quality,shelf life,and resilience.It also explores the potential of base and prime editing technologies,which offer greater precision and reduced risk of unintended mutations.Despite these advancements,the practical use of genome editing in horticulture faces persistent challenges,including inefficient delivery systems,off-target effects,and the limited regeneration capacity of many species.Furthermore,regulatory ambiguity,ethical considerations,and public skepticism continue to shape the global acceptance and commercialization of genome-edited crops.Integrating CRISPR-based tools into mainstream horticultural breeding programs offers a pathway for the development of climate-resilient,high-quality crops and for sustainable agricultural development in the face of global challenges. 展开更多
关键词 Breeding CRISPR MUTAGENESIS Off-target effects TRANSGENE
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Checklist of marine fishes in the Beibu Gulf:fish classification,resource protection,and biodiversity challenge 被引量:1
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作者 Zhisen LUO Murong YI +9 位作者 xiaodong yang Xiao CHEN Jinxi WANG Changping JIANG Fengming LIU Konglan LUO Xiongbo HE Hung-Du LIN Bin KANG Yunrong YAN 《Journal of Oceanology and Limnology》 2025年第1期232-247,共16页
Marine fish diversity in the Beibu Gulf from 2014 to 2022 was analyzed,using various methods including at-sea fisheries resource surveys,fishing port surveys,underwater survey techniques,and data from literature,books... Marine fish diversity in the Beibu Gulf from 2014 to 2022 was analyzed,using various methods including at-sea fisheries resource surveys,fishing port surveys,underwater survey techniques,and data from literature,books,and databases,from which 1059 fish species across 40 orders,166 families,and 503 genera were identified.Among them,Acanthuriformes displayed the highest diversity,followed by Carangiformes and Perciformes.Notably,eight alien species were found in the Beibu Gulf.The International Union for Conservation of Nature(IUCN)Red List assessment revealed 51threatened species,primarily cartilaginous fish.Taxonomic changes affected 88.70%of species due to classification adjustments,misidentifications,and junior synonymy.This study contributed new data of the gulf,including one additional order,six new families,34 new genera,and 81 new species,emphasizing the dynamic nature of marine ecosystems.Fish diversity in the gulf was relatively lower than the broader South China Sea,attributed to limited habitats and survey methods.Different survey methods,such as gill nets,trap nets,and underwater cameras,yielded varying results.Ocean currents may have transported deep-sea species into the Beibu Gulf,leading to accidental records.Research gaps exist in unexplored areas,warranting further investigation.Therefore,the Beibu Gulf hosts significant marine biodiversity,but taxonomic challenges and undiscovered species require new research and conservation efforts. 展开更多
关键词 northwestern South China Sea new record taxonomic change fish diversity survey method
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Metal nanoparticles decorated CoFe-(oxy)hydroxysulfides nanosheets fabricated by a general strategy for electrocatalytic water splitting 被引量:1
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作者 xiaodong yang Haochen Shen +7 位作者 Xiaoming Xiao Zhichao Li Qi Zhou Wei yang Bin Jiang Yongli Sun Luhong Zhang Zhenhua Yan 《Journal of Energy Chemistry》 2025年第1期26-38,共13页
This study presents a novel method to fabricate metal-decorated,sulfur-doped layered double hydroxides(M/SLDH)through spontaneous redox and sulfurization processes.The developed Ag/SLDH and Pt/SLDH catalysts with abun... This study presents a novel method to fabricate metal-decorated,sulfur-doped layered double hydroxides(M/SLDH)through spontaneous redox and sulfurization processes.The developed Ag/SLDH and Pt/SLDH catalysts with abundant heterogeneous interfaces and hierarchical nanostructures demonstrated outstanding oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)performance,achieving low overpotentials of 212 and 35 mV at 10 mA cm^(-2)in 1 M KOH,respectively.As both anode and cathode in water splitting,they required only 1.47 V to reach 10 mA cm^(-2)and exhibited high structural robustness,maintaining stability at 1000 mA cm^(-2)for 300 h.In-situ Raman analysis revealed that the synergistic effects of metal nanoparticles and S doping significantly promote the transformation into the S-Co1-xFexOOH layer,which serves as the active phase for water oxidation.Additionally,ultraviolet photoelectron spectroscopy(UPS)and density functional theory(DFT)analyses indicated that incorporating metal nanoparticles and S doping increase electron density near the Fermi level and reduce reaction energy barriers,thus enhancing intrinsic OER and HER activities.This study provides a scalable strategy for synthesizing high-performance electrocatalysts for water splitting,with promising potential for broader applications. 展开更多
关键词 LDH Spontaneous reaction Metal nanoparticles Water splitting
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Fast Ion Gates without the Lamb-Dicke Approximation by Robust Quantum Optimal Control
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作者 Ran Liu xiaodong yang +2 位作者 Yiheng Lin Yao Lu Jun Li 《Chinese Physics Letters》 2025年第8期75-82,共8页
We present a robust quantum optimal control framework for implementing fast entangling gates on ion-trap quantum processors.The framework leverages tailored laser pulses to drive the multiple vibrational sidebands of ... We present a robust quantum optimal control framework for implementing fast entangling gates on ion-trap quantum processors.The framework leverages tailored laser pulses to drive the multiple vibrational sidebands of the ions to create phonon-mediated entangling gates and,unlike the state of the art,requires neither weakcoupling Lamb-Dicke approximation nor perturbation treatment.With the application of gradient-based optimal control,it enables finding amplitude-and phase-modulated laser control protocols that work without the Lamb-Dicke approximation,promising gate speeds on the order of microseconds comparable to the characteristic trap frequencies.Also,robustness requirements on the temperature of the ions and initial optical phase can be conveniently included to pursue high-quality fast gates against experimental imperfections.Our approach represents a step in speeding up quantum gates to achieve larger quantum circuits for quantum computation and simulation,and thus can find applications in near-future experiments. 展开更多
关键词 quantum optimal control framework gradient based optimal control quantum computation Lamb Dicke approximation fast ion gates tailored laser pulses entangling gates robust quantum optimal control
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Application of MICP in ameliorating erosion resistance of soil on reservoir banks
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作者 Huiling Geng Weiquan Zhao +2 位作者 xiaodong yang Huan Zha Yipin Wang 《River》 2025年第4期445-461,共17页
Regulating reservoirs with clay slopes are prone to severe erosion caused by wind-wave actions and water-level fluctuations.Conventional bank protection methods often rely on rigid structures,which can adversely affec... Regulating reservoirs with clay slopes are prone to severe erosion caused by wind-wave actions and water-level fluctuations.Conventional bank protection methods often rely on rigid structures,which can adversely affect ecosystems.This study explores the use of microbially induced carbonate precipitation(MICP)for soil stabilization to enhance the erosion resistance of clay slopes and support plant growth.Through unconfined compressive strength(UCS)tests and seed germination trials,an optimal MICP treatment formula was identified.Using calcium acetate as the calcium source,with a cementation solution concentration of 0.5 mol/L and a reagent dosage of 23%,the UCS increased by 235.3%(from 20.5 to 68.7 kPa).Euphrasia pectinate Ten and Sesbania cannabina were found to be suitable plant species for MICP-treated soil,achieving germination rates of 45%and 30%,respectively.Disintegration and wave erosion tests demonstrated that the disintegration rate of MICP-treated specimens decreased from 23.1%to 0%,and the erosion mass rate decreased from 1.5%to 0.2%.Field tests further validated the effectiveness of MICP,with treated slopes exhibiting no erosion and demonstrating penetration and shear strengths of 47.9 kPa and 114.5 kPa,respectively—2.5 and 3.2 times higher than those of untreated slopes.The MICP process facilitates calcium carbonate deposition,reduces pore space,and enhances interparticle bonding.Calcium carbonate crystals derived from calcium acetate exhibited stronger adhesion than those formed from calcium chloride.Filamentous organic matter was closely adhered between soil particles,further enhancing the ductility and resistance to hydraulic erosion.Additionally,acetate ions reduce MICP toxicity to plants and enhance microbial activity and nutrient cycling,creating more favorable conditions for plant growth. 展开更多
关键词 field tests microbially induced calcium carbonate precipitation(MICP) seed germination unconfined compressive strength(UCS) water erosion resistance
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Design and synthesis of novel saponin-triazole derivatives in the regulation of adipogenesis
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作者 Yongsheng Fang Zhiyun Zhu +7 位作者 Chun Xie Dazhen Xia Huimin Zhao Zihui Wang Qian Lu Caimei Zhang Wenyong Xiong xiaodong yang 《Chinese Journal of Natural Medicines》 2025年第8期920-931,共12页
Saponins associated with Panax notoginseng(P.notoginseng)demonstrate significant therapeutic efficacy across multiple diseases.However,certain high-yield saponins face limited clinical applications due to their reduce... Saponins associated with Panax notoginseng(P.notoginseng)demonstrate significant therapeutic efficacy across multiple diseases.However,certain high-yield saponins face limited clinical applications due to their reduced pharmacological efficacy.This study synthesized and evaluated 36 saponin-1,2,3-triazole derivatives of ginsenosides Rg1/Rb1 and notoginsenoside R1 for anti-adipogenesis activity in vitro.The research revealed that the ginsenosides Rg1-1,2,3-triazole derivative a17 demonstrates superior adipogenesis inhibitory effects.Structure-activity relationships(SARs)analysis indicates that incorporating an amidyl-substituted 1,2,3-triazole into the saponin side chain via Click reaction enhances anti-adipogenesis activity.Additionally,several other derivatives exhibit general adipogenesis inhibition.Compound a17 demonstrated enhanced potency compared to the parent ginsenoside Rg1.Mechanistic investigations revealed that a17 exhibits dose-dependent inhibition of adipogenesis in vitro,accompanied by decreased expression of preadipocytes.Peroxisome proliferator-activated receptorγ(PPARγ),fatty acid synthase(FAS),and fatty acid binding protein 4(FABP4)adipogenesis regulators.These findings establish the ginsenoside Rg1-1,2,3-triazole derivative a17 as a promising adipocyte differentiation inhibitor and potential therapeutic agent for obesity and associated metabolic disorders.This research provides a foundation for developing effective therapeutic approaches for various metabolic syndromes. 展开更多
关键词 Panax notoginseng Saponin-triazole derivatives Adipocyte differentiation and maturation Lipid metabolism Structure-activity relationships
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Pharmacokinetics and Safety of Chiglitazar in Patients with Renal Impairment: A Multicenter, Open-label, Parallel-controlled Phase I Clinical Trial
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作者 Jinjie Yuan Jia Yu +9 位作者 Jiwen Sun Huan Wang Guoyuan Lu Wengang Sha xiaodong yang Haixiang Cao Yu Chen Desi Pan Xinhao Wang Hua Zhang 《Journal of Clinical and Nursing Research》 2025年第5期252-263,共12页
Background:Chiglitazar is a novel pan-agonist that can activate all three subtypes of peroxisome proliferator-activated receptor.It was approved for the treatment of type 2 diabetes mellitus as monotherapy on October ... Background:Chiglitazar is a novel pan-agonist that can activate all three subtypes of peroxisome proliferator-activated receptor.It was approved for the treatment of type 2 diabetes mellitus as monotherapy on October 19,2021,and as combination therapy with metformin when using metformin alone failed in blood glucose control on July 16,2024,by the National Medical Products Administration(NMPA)in China.However,pharmacokinetic(PK)study of this product in patients with renal impairment have not yet been conducted.The purpose of this study is to evaluate the effects of renal impairment on the PK and safety after a single oral dose of Chiglitazar.Methods:This multicenter,open-label,parallel-controlled,single-dose Phase I clinical trial(NCT 05515458)enrolled 24 participants(12/group)with severe renal impairment(SRI)or normal renal function(NRF).All participants received a single oral dose of 48 mg chiglitazar after breakfast and the PK and safety was evaluated.Results:The median Tmax was similar in both SRI and NRF groups(5.01 vs.5.02 hours).The geometric mean ratios(GMR)for Cmax,AUC0-t,and AUC0-∞were 0.807(90%confidence interval[CI]:0.697–0.935),0.853(90%CI:0.713–1.02),and 0.855(90%CI:0.716–1.02),respectively,indicating that SRI did not significantly affect the exposure of chiglitazar.The Cmax was weakly positively correlated with eGFR(r=0.4798,P=0.0177)and creatinine clearance rate(r=0.4667,P=0.0215).Urinary excretion of chiglitazar was negligible in the SRI group,with average values of Ae0-t=2,900 ng,Fe0-t=0.0060%,and CLR=0.323 mL/h within 0–72 hours post-dose.The treatment-emergent adverse event(TEAE)incidence in the SRI group(16.7%,2/12)was comparable to that in the NRF group(25%,3/12).All TEAEs were of mild severity and were adjudicated by the investigators to be unrelated to chiglitazar.No serious AE were reported.Chiglitazar exhibits a favorable safety profile.Conclusion:Severe renal impairment does not significantly affect the PK and safety of chiglitazar,and no dose adjustment for mild,moderate,and severe renal impairments is required. 展开更多
关键词 Chiglitazar PHARMACOKINETICS Renal impairment SAFETY
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A universal strategy to synthesize amorphous/crystalline P,Mo dual-doped CoNiS nanostructures for overall water splitting
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作者 xiaodong yang Haochen Shen +4 位作者 Xiaoming Xiao Wei yang Zhichao Li Na yang Luhong Zhang 《Journal of Materials Science & Technology》 2025年第1期18-28,共11页
In this work,P and Mo dual-doped CoNiS(PMo-CoNiS)nanosheet arrays were successfully constructed through a common solvothermal treatment.The precise doping of P and Mo species into the CoNiS can regulate the microstruc... In this work,P and Mo dual-doped CoNiS(PMo-CoNiS)nanosheet arrays were successfully constructed through a common solvothermal treatment.The precise doping of P and Mo species into the CoNiS can regulate the microstructures and meanwhile endow with PMo-CoNiS abundant amorphous/crystalline heterointerfaces,which can adjust the electronic structure,thus enhancing the intrinsic activity of hydro-gen evolution reaction(HER)and oxygen evolution reaction(OER).As a result,ultra-low overpotentials of merely 156 and 58 mV are required to deliver a current density of 10 mA cm^(−2) for OER and HER,respec-tively,and the electrocatalysts PMo-CoNiS also exhibit low Tafel slopes and maintain robust stability for 48 h in alkaline media at a high current density of 50 mA cm^(−2).In addition,in an assembled electrolyte cell for overall water splitting,a voltage as low as 1.48 V is sufficient to yield a current density of 10 mA cm^(−2).Density functional theory(DFT)calculations further confirmed that the enhanced OER and HER result from the optimized OH^(∗)and H^(∗)adsorption energy of PMo-CoNiS due to P,Mo dual doping and generated interfacial effect.This work may offer an avenue for designing low-cost bifunctional catalysts with superior catalytic activity and provide a new application strategy for broader applications in various electrocatalytic fields. 展开更多
关键词 Transition metal sulfides Dual doping Amorphous/crystalline hybrid Water splitting
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A novel metastable structure and superconductivity of hydrogen-rich compound CdH_(6) under pressure
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作者 Yan Yan Chengao Jiang +5 位作者 Wen Gao Rui Chen xiaodong yang Runru Liu Lihua yang Lili Wang 《Chinese Physics B》 2025年第8期240-246,共7页
The particle swarm optimization algorithm has predicted a series of binary cadmium hydrides that could be dynamically stable at pressures between 100 GPa and 300 GPa.These low-energy phases are composed of both Cd ato... The particle swarm optimization algorithm has predicted a series of binary cadmium hydrides that could be dynamically stable at pressures between 100 GPa and 300 GPa.These low-energy phases are composed of both Cd atoms and H_(2)molecules.Here,we propose a hitherto unknown metastable Cmcm-CdH_(6)phase,consisting of one-dimensional zigzag graphite-like hydrogenic H_(6)chains,quasimolecular H_(2)units and Cd atoms,which is metallic above 290 GPa.Due to H_(2)s→Cd d donation and Cd d→H_(2)σ^(*)back-donation,the electrons occupy antibonding orbitals for both types of hydrogen atoms.This results in weakened chemical bonds in the Cmcm-CdH_(6)phase via a Kubas-like mechanism,promoting the emergence of high superconductivity,which is estimated to be up to~60 K at 290 GPa.This work will inspire the search for superconductivity in materials based on group IIB hydrides under pressure. 展开更多
关键词 high pressure hydrogen-rich compounds SUPERCONDUCTIVITY
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Influence Characteristics of Laser Transmission Amplitude Fluctuation Based on Turbulent Medium
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作者 xiaodong yang Ming Gao 《Optics and Photonics Journal》 2020年第6期95-104,共10页
<div style="text-align:justify;"> In order to study the transmission characteristics of laser in atmospheric turbulent medium and understand the influence degree of various factors on amplitude fluctua... <div style="text-align:justify;"> In order to study the transmission characteristics of laser in atmospheric turbulent medium and understand the influence degree of various factors on amplitude fluctuation, by means of smooth perturbation method, this paper establishes a theory model of amplitude fluctuation of laser propagation in turbulent medium by using the smooth perturbation method and reflects the amplitude fluctuation degree, carries out specific discussion on each influence factor. The results show that the larger the wavelength, the more stable the amplitude fluctuation. With the increase of laser section radius, the amplitude fluctuates sharply and then decreases slowly after reaching the peak. Transmission distance is the main influence factor of amplitude fluctuation. With the increase of transmission distance, the amplitude fluctuation will become more obvious. The amplitude acquisition can be comprehensively modulated in a specific transmission distance by wavelength and section ra-dius, so as to ensure the stability of the received laser and provide a theoretical basis for the interferometry technology. </div> 展开更多
关键词 Amplitude Fluctuation Turbulent Medium Smooth Perturbation Method Section Radius Interferometry
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PBS缓冲区部分车道中断的车辆应急调度研究 被引量:1
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作者 杨晓冬 许翔 陆群 《软件工程与应用》 2021年第6期737-745,共9页
为缓解产线压力及适应订单随机性,汽车制造企业往往会在涂装车间与总装车间中设立涂装车身缓冲区(Painted Body Storage-PBS)。以最常见的线性缓冲区作为研究对象,针对其中可能出现的部分车道中断的突发情况,为提高产线的柔性,降低企业... 为缓解产线压力及适应订单随机性,汽车制造企业往往会在涂装车间与总装车间中设立涂装车身缓冲区(Painted Body Storage-PBS)。以最常见的线性缓冲区作为研究对象,针对其中可能出现的部分车道中断的突发情况,为提高产线的柔性,降低企业的损失,提出了一种通过遗传算法来对PBS缓冲区的出库和入库进行“自适应循环优化”的实时动态调配方法。首先,利用车身信息、位置以及出库计划将可运行的待出库车身构建模型并通过遗传算法求解。然后,根据求解出来的出库模型结果对未入库车身进行构建匹配模型,获得的多种入库模型再通过融合启发式规则的遗传算法来进行确定入库以及得到之后的出库模型,从而形成一种出入库“自适应循环优化”的应急调度方案。最后,通过案例分析验证了该方法的有效性。 展开更多
关键词 PBS缓冲区 遗传算法 自适应循环优化 应急调度
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西双版纳热带季节雨林木本植物的beta多样性:空间、环境与林分结构的作用 被引量:2
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作者 施国杉 刘峰 +6 位作者 曹光宏 陈典 夏尚文 邓云 王彬 杨效东 林露湘 《生物多样性》 CSCD 北大核心 2024年第12期56-68,共13页
Beta多样性能够度量物种组成的时空变化格局,其驱动因子(例如空间与环境)一直是生态学研究的热点之一。然而,林分结构作为森林群落重要的特征参数,其对木本植物beta多样性的驱动作用还知之甚少。本研究以云南纳板河热带季节雨林20ha动... Beta多样性能够度量物种组成的时空变化格局,其驱动因子(例如空间与环境)一直是生态学研究的热点之一。然而,林分结构作为森林群落重要的特征参数,其对木本植物beta多样性的驱动作用还知之甚少。本研究以云南纳板河热带季节雨林20ha动态样地的木本植物为研究对象,在不同取样尺度将beta多样性分解为物种周转组分和物种丰富度差异组分,通过基于距离矩阵的多元回归分析和方差分解,解析空间、环境和林分结构在beta多样性及其两个组分格局形成中的相对作用。结果表明:(1)Beta多样性、物种周转组分和物种丰富度差异组分随取样尺度的增大而减小,物种周转组分始终在beta多样性构成中占主导部分。(2)环境距离对beta多样性和物种周转组分具有相对较高的解释率,随着取样尺度增大,单纯的环境距离对beta多样性的解释率从8.8%增长到23.9%,对物种周转组分的解释率从5.1%增长到26.5%;而环境距离对物种丰富度差异组分几乎没有作用。(3)不同取样尺度林分结构距离对beta多样性均具有相对较高的解释率(11.3%-25.1%),并且对物种周转组分和物种丰富度差异组分始终保持一定的解释率。同时,无论是否包含林分结构距离作为解释变量,单纯的空间距离对beta多样性及其两个组分的解释率都很低。本研究支持环境过滤对beta多样性和物种周转组分的相对重要性随着取样尺度的增大而增大的观点,同时发现扩散限制在局域尺度beta多样性格局形成中的作用却十分有限。本研究进一步揭示了能够指示光的可利用性和异质性的林分结构,与地形、土壤等其他环境因子一样,也是beta多样性格局形成的重要驱动力,建议未来深入研究林分结构在木本植物多样性格局形成中的作用机制。 展开更多
关键词 物种周转组分 物种丰富度差异组分 环境过滤 扩散限制 方差分解 取样尺度
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亲子间的手机博弈:家庭关系对青少年心理健康的影响研究 被引量:11
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作者 杨晓冬 李怡静 魏然 《全球传媒学刊》 CSSCI 2022年第3期35-57,共23页
本研究以生态系统理论、媒介时间置换假说为理论框架,探讨家庭关系质量是如何通过青少年手机使用强度,以及因手机使用产生的亲子冲突影响青少年心理健康水平的。实证结果显示:家庭关系质量负向影响青少年手机使用强度;青少年的手机使用... 本研究以生态系统理论、媒介时间置换假说为理论框架,探讨家庭关系质量是如何通过青少年手机使用强度,以及因手机使用产生的亲子冲突影响青少年心理健康水平的。实证结果显示:家庭关系质量负向影响青少年手机使用强度;青少年的手机使用强度正向影响因手机使用产生的亲子冲突频率。此外,因手机使用产生的亲子冲突不仅对青少年的自尊和生活满意度产生负向影响,且正向影响青少年的孤独感和抑郁程度。 展开更多
关键词 家庭关系 手机使用强度 青少年心理健康 亲子冲突
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AVIRIS高光谱数据空-谱特征在植被分类中的对比分析 被引量:3
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作者 付元元 杨贵军 +5 位作者 段丹丹 张永涛 顾晓鹤 杨小冬 徐新刚 李振海 《智慧农业(中英文)》 2020年第1期68-76,共9页
植被分类是高光谱影像分类中的特定应用问题,光谱特征和空间特征是植被分类中常用的两类特征,比较这两类特征的性能,对实际植被分类应用中选择合适的特征类型或两者的有效结合具有指导意义。用主成分分析(PCA)提取光谱特征时,常选择前... 植被分类是高光谱影像分类中的特定应用问题,光谱特征和空间特征是植被分类中常用的两类特征,比较这两类特征的性能,对实际植被分类应用中选择合适的特征类型或两者的有效结合具有指导意义。用主成分分析(PCA)提取光谱特征时,常选择前几个主成分(PCs)作为光谱特征,虽然它们包含较大的信息量但并不能保证较高的类别可分性和分类正确率,针对这一问题本研究提出了一种混合特征提取方法,对高光谱影像在PCA的基础上用改进的基于分散矩阵的特征选择方法选出具有较高类别可分性的PCs用于后续分类。利用一景AVIRIS高光谱植被影像,从分类精度的角度,首先比较了所提出的混合特征提取方法和原始PCA、独立主成分分析(ICA)及线性判别分析(LDA) 3种常用子空间特征提取方法在高光谱影像植被分类中的性能。试验结果表明所提出的混合特征提取方法在研究中数据集1和2上均获得了最高的总体分类正确率,分别为82.7%和86.5%。与原始PCA相比,本研究提出的混合特征提取方法的总体分类正确率,在数据集1和2上分别提高了1.5%和2.5%。由此阐明了所提出的混合特征提取方法在高光谱植被分类中的有效性。对光谱特征和空间特征在高光谱影像植被分类性能的比较中,总体上空间特征获得的分类正确率比光谱特征高,特别是Gabor特征,在两个数据集上均获得了最高的总体分类正确率分别为95.5%和96.7%。由此表明空间特征较光谱特征在高光谱影像植被分类中更具优势。本研究结果为后续改进空-谱特征方法及其两者有效结合,进一步提高植被分类正确率提供了参考。 展开更多
关键词 高光谱影像 植被分类 光谱特征 空间特征 混合特征提取方法 分散矩阵 主成分分析
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高温环境作用下T800碳纤维/AC631双马来酰亚胺复合材料的疲劳行为 被引量:2
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作者 高禹 杨晓东 +2 位作者 董尚利 王柏臣 包建文 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2022年第3期89-95,共7页
在200℃高温环境下对多向铺层T800/AC631双马来酰亚胺复合材料进行了长时间暴露处理,测试了复合材料的质损率、动态力学性能和拉伸强度。根据拉伸强度确定疲劳应力水平,并测试了高温环境处理前后材料的疲劳性能。采用宏观目视和超声C扫... 在200℃高温环境下对多向铺层T800/AC631双马来酰亚胺复合材料进行了长时间暴露处理,测试了复合材料的质损率、动态力学性能和拉伸强度。根据拉伸强度确定疲劳应力水平,并测试了高温环境处理前后材料的疲劳性能。采用宏观目视和超声C扫描对复合材料疲劳损伤状况进行了表征和分析。结果表明,随着高温环境处理时间的延长,复合材料的质损率先迅速增加再缓慢增加。复合材料动态力学性能的变化归因于高温环境处理后的复合材料发生了一定程度的后固化、物理老化和界面局部脱粘。高温环境处理1000 h后,复合材料出现了轻微损伤,其疲劳寿命与原始态相比明显下降。复合材料的疲劳破坏模式主要为纤维断裂和铺层分层开裂。经历高温环境处理的T800/AC631复合材料的刚度明显下降,迟滞回能环轴线斜率和面积减少,表明复合材料出现了明显的高温老化损伤。 展开更多
关键词 碳/树脂基复合材料 高温环境 疲劳性能 动态力学热分析 超声C扫描
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西藏林芝地区野生食用菌重金属污染状况调查 被引量:4
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作者 杨晓东 尼珍 +4 位作者 闻剑 胡曙光 苏祖俭 黄伟雄 曹艳娥 《西藏医药》 2017年第6期52-56,共5页
目的了解西藏林芝地区野生食用菌中重金属的污染状况及分布特点。方法在林芝地区7个区县采集野生食用菌共7类204份蔬菜进行铅、镉、汞、砷的检测。结果林芝地区各类野生食用菌品种间不同程度受到镉、汞、砷的污染,其中镉为4.4%,汞超标率... 目的了解西藏林芝地区野生食用菌中重金属的污染状况及分布特点。方法在林芝地区7个区县采集野生食用菌共7类204份蔬菜进行铅、镉、汞、砷的检测。结果林芝地区各类野生食用菌品种间不同程度受到镉、汞、砷的污染,其中镉为4.4%,汞超标率为4.9%,砷为6.4%,主要污染品种为獐子菌、松茸;镉平均含量较高的地区是察隅县,汞平均含量较高的地区是巴宜区和工布江达县;砷平均含量较高的地区是工布江达县。结论林芝地区野生食用菌中受到不同程度的重金属污染,应加强对重点区域重点品种的监测。 展开更多
关键词 食用菌 重金属 食品污染物
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2010年-2015年SEER数据库肺腺鳞癌患者临床特征及预后分析 被引量:13
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作者 詹成 江天 +2 位作者 杨晓冬 郭卫刚 谭黎杰 《中国肺癌杂志》 CAS CSCD 北大核心 2018年第8期600-609,共10页
背景与目的肺癌发病率和死亡率均位居所有恶性肿瘤的第一,严重影响人类健康。非小细胞肺癌(non-small cell lung cancer,NSCLC)中常见病理类型为腺癌和鳞癌,临床研究和关注较多,而肺腺鳞癌是一种较为罕见的肺癌病理类型,其临床特征及预... 背景与目的肺癌发病率和死亡率均位居所有恶性肿瘤的第一,严重影响人类健康。非小细胞肺癌(non-small cell lung cancer,NSCLC)中常见病理类型为腺癌和鳞癌,临床研究和关注较多,而肺腺鳞癌是一种较为罕见的肺癌病理类型,其临床特征及预后相关因素尚未完全明确。本研究即对肺腺鳞癌的临床特征及预后进行分析,并构建了列线图来预测患者的预后。方法我们纳入了2010年-2015年美国SEER(Surveillance,Epidemiology,and End Results)数据库中的肺腺鳞癌数据,与同期的肺腺癌和肺鳞癌的临床特征和预后进行了比较。随后我们采用单因素和多因素分析研究了肺腺鳞癌患者预后的独立相关因素,以此构建了列线图并进行了验证。结果我们一共入组了肺腺鳞癌患者1,453例。与同期的肺腺癌和肺鳞癌患者相比较,肺腺鳞癌患者在大多数变量中的分布情况均介于肺腺癌和鳞癌之间,其预后也优于肺鳞癌但差于肺腺癌患者。多因素分析发现,年龄、分化程度、肿瘤-淋巴结-转移(tumor-node-metastasis,TNM)、手术和化疗是患者预后的独立影响因素(P均<0.001)。我们以此构建了列线图,其C-index为0.783(0.767-0.799),区分度检验和一致性检验均表明这一列线图可以有效地预测患者预后。结论肺腺鳞癌具有独特的临床病理和预后特征。年龄、分化、T、N、M、手术和化疗状况是肺腺鳞癌患者预后的独立预测因素。我们以此构建的列线图可以较好地预测患者预后。 展开更多
关键词 肺肿瘤 腺鳞癌 列线图 SEER数据库
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A power and thermal management system for long endurance hypersonic vehicle 被引量:7
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作者 Liang GUO Liping PANG +2 位作者 xiaodong yang Jingquan ZHAO Desheng MA 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第2期29-40,共12页
Due to the pneumatic heating and combustion effect,the scramjet engine of hypersonic vehicle faces high temperature challenge.It is necessary to comprehensively consider its thermal management and power generation tog... Due to the pneumatic heating and combustion effect,the scramjet engine of hypersonic vehicle faces high temperature challenge.It is necessary to comprehensively consider its thermal management and power generation together.A new Power and Thermal Management System(PTMS)combined with Supercritical Carbon Dioxide(SCO_(2))closed Brayton cycle and fuel vapor turbine is proposed and discussed in this paper.The new PTMS can meet the cooling requirement of hypersonic vehicle at Mach number 6–7,and avoid the coking and scrapping in the scramjet cooling channels.Compared with the PTMS only based on fuel vapor turbine,the new PTMS utilizes the waste heat of scramjet to generate more electricity.In addition,it can reduce the use of fuel sink for cooling,and the additional weight penalty can be compensated for long endurance hypersonic flight. 展开更多
关键词 Fuel vapor turbine Hypersonic vehicle Power and thermal management system SCRAMJET Supercritical carbon dioxide
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Influence of soil microorganisms and physicochemical properties on plant diversity in an arid desert of Western China 被引量:6
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作者 xiaodong yang Yanxin Long +5 位作者 Binoy Sarkar Yan Li Guanghui Lv Arshad Ali Jianjun yang Yue-E.Cao 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第6期2645-2659,共15页
Soil microorganisms and physicochemical properties are considered the two most influencing factors for maintaining plant diversity.However,the operational mechanisms and which factor is the most influential manipulato... Soil microorganisms and physicochemical properties are considered the two most influencing factors for maintaining plant diversity.However,the operational mechanisms and which factor is the most influential manipulator remain poorly understood.In this study,we examine the collaborative influences of soil physicochemical properties(i.e.,soil water,soil organic matter(SOM),salinity,total phosphorus and nitrogen,pH,soil bulk density and fine root biomass)and soil microorganisms(fungi and bacteria)on plant diversity across two types of tree patches dominated by big and small trees(big trees:height≥7 m and DBH≥60 cm;small trees:height≤4.5 m and DBH≤20 cm)in an arid desert region.Tree patch is consists of a single tree or group of trees and their accompanying shrubs and herbs.It was hypothesized that soil physicochemical properties and microorganisms affect plant diversity but their influence differ.The results show that plant and soil microbial diversity increased with increasing distances from big trees.SOM,salinity,fine root biomass,soil water,total phosphorus and total nitrogen contents decreased with increasing distance from big trees,while pH and soil bulk density did not change.Plant and soil microbial diversity were higher in areas close to big trees compared with small trees,whereas soil physicochemical properties were opposite.The average contribution of soil physicochemical properties(12.2%-13.5%)to plant diversity was higher than microbial diversity(4.8%-6.7%).Salinity had the largest negative affect on plant diversity(24.7%-27.4%).This study suggests that soil fungi constrain plant diversity while bacteria improve it in tree patches.Soil physicochemical properties are the most important factor modulating plant diversity in arid desert tree patches. 展开更多
关键词 Arid ecosystem Soil microbial diversity Soil physicochemical properties Plant diversity Soil salinity
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Dynamic analysis of a rotating tapered cantilever Timoshenko beam based on the power series method 被引量:6
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作者 xiaodong yang Shaowen WANG +2 位作者 Wei ZHANG Zhaohong QIN Tianzhi yang 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第10期1425-1438,共14页
The mathematical modeling of a rotating tapered Timoshenko beam with preset and pre-twist angles is constructed. The partial differential equations governing the six degrees, i.e., three displacements in the axial, fl... The mathematical modeling of a rotating tapered Timoshenko beam with preset and pre-twist angles is constructed. The partial differential equations governing the six degrees, i.e., three displacements in the axial, flapwise, and edgewise directions and three cross-sectional angles of torsion, flapwise bending, and edgewise bending, are obtained by the Euler angle descriptions. The power series method is then used to inves- tigate the natural frequencies and the corresponding complex mode functions. It is found that all the natural frequencies are increased by the centrifugal stiffening except the twist frequency, which is slightly decreased. The tapering ratio increases the first transverse, torsional, and axial frequencies, while decreases the second transverse frequency. Because of the pre-twist, all the directions are gyroscopically coupled with the phase differences among the six degrees. 展开更多
关键词 rotating Timoshenko beam power series method natural frequency gyro-scopic coupling
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