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The first discovery of non-avian dinosaur egg and bone fossils in the Hefei Basin 被引量:1
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作者 WANG Qiang DONG Zhe +4 位作者 MAO Lei ZHU Xu-Feng CHEN Yan-Bin HUANG Jian-Dong DING Hai-Dong 《古脊椎动物学报(中英文)》 北大核心 2025年第3期248-252,共5页
This report is about the first record of non-avian dinosaur eggs in the Hefei Basin,Anhui Province,China.Based on the combination of elongated egg body,linear ridges on the outer surface and two structure layer,the eg... This report is about the first record of non-avian dinosaur eggs in the Hefei Basin,Anhui Province,China.Based on the combination of elongated egg body,linear ridges on the outer surface and two structure layer,the eggs can be referred to Elongatoolithidae.The gradual boundary between the cone and the column layers as well as the relative thin eggshell(less than 1 mm)indicates its affinity within Elongatoolithus.The eggs are identified as Elongatoolithus oosp.,as they were severely compressed and experienced erosion on both inner and outer surfaces.The discovery of egg fossil in the Hefei Basin offers evidence for stratum comparison in this region and supplements the diversity of egg fossils in Anhui.Meanwhile,this discovery also enriches the paleogeographic distribution of elongatoolithids. 展开更多
关键词 Hefei Basin Upper Cretaceous Zhangqiao Formation egg fossil Elongatoolithidae
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Impacts of synoptic weather patterns on Hefei's ozone in warm season and analysis of transport pathways during extreme pollution events 被引量:1
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作者 Feng Hu Pinhua Xie +5 位作者 Jin Xu Ang Li Yinsheng Lv Zhidong Zhang Jiangyi Zheng Xin Tian 《Journal of Environmental Sciences》 2025年第10期371-384,共14页
Extreme ozone pollution events(EOPEs)are associated with synoptic weather patterns(SWPs)and pose severe health and ecological risks.However,a systematic investigation of themeteorological causes,transport pathways,and... Extreme ozone pollution events(EOPEs)are associated with synoptic weather patterns(SWPs)and pose severe health and ecological risks.However,a systematic investigation of themeteorological causes,transport pathways,and source contributions to historical EOPEs is still lacking.In this paper,the K-means clustering method is applied to identify six dominant SWPs during the warm season in the Yangtze River Delta(YRD)region from 2016 to 2022.It provides an integrated analysis of the meteorological factors affecting ozone pollution in Hefei under different SWPs.Using the WRF-FLEXPART model,the transport pathways(TPPs)and geographical sources of the near-surface air masses in Hefei during EOPEs are investigated.The results reveal that Hefei experienced the highest ozone concentration(134.77±42.82μg/m^(3)),exceedance frequency(46 days(23.23%)),and proportion of EOPEs(21 instances,47.7%)under the control of peripheral subsidence of typhoon(Type 5).Regional southeast winds correlated with the ozone pollution in Hefei.During EOPEs,a high boundary layer height,solar radiation,and temperature;lowhumidity and cloud cover;and pronounced subsidence airflow occurred over Hefei and the broader YRD region.The East-South(E_S)patterns exhibited the highest frequency(28 instances,65.11%).Regarding the TPPs and geographical sources of the near-surface air masses during historical EOPEs.The YRD was the main source for land-originating air masses under E_S patterns(50.28%),with Hefei,southern Anhui,southern Jiangsu,and northern Zhejiang being key contributors.These findings can help improve ozone pollution early warning and control mechanisms at urban and regional scales. 展开更多
关键词 OZONE Objective weather classification Transport pathway Source attribution Hefei
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Upper crustal azimuthal anisotropy and seismogenic tectonics of the Hefei segment of the Tan-Lu Fault Zone from ambient noise tomography 被引量:1
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作者 Cheng Li HuaJianYao +4 位作者 Song Luo HaiJiang Zhang LingLi Li XiaoLi Wang ShengJun Ni 《Earth and Planetary Physics》 2025年第2期253-265,共13页
The Tan-Lu Fault Zone is a large NNE-trending fault zone that has a substantial effect on the development of eastern China and its earthquake disaster prevention efforts. Aiming at the azimuthally anisotropic structur... The Tan-Lu Fault Zone is a large NNE-trending fault zone that has a substantial effect on the development of eastern China and its earthquake disaster prevention efforts. Aiming at the azimuthally anisotropic structure in the upper crust and seismogenic tectonics in the Hefei segment of this fault, we collected phase velocity dispersion data of fundamental mode Rayleigh waves from ambient noise cross-correlation functions of ~400 temporal seismographs in an area of approximately 80 × 70 km along the fault zone. The period band of the dispersion data was ~0.5–10 s. We inverted for the upper crustal three-dimensional(3-D) shear velocity model with azimuthal anisotropy from the surface to 10 km depth by using a 3-D direct azimuthal anisotropy inversion method. The inversion result shows the spatial distribution characteristics of the tectonic units in the upper crust. Additionally, the deformation of the Tan-Lu Fault Zone and its conjugated fault systems could be inferred from the anisotropy model. In particular, the faults that have remained active from the early and middle Pleistocene control the anisotropic characteristics of the upper crustal structure in this area. The direction of fast axes near the fault zone area in the upper crust is consistent with the strike of the faults, whereas for the region far away from the fault zone, the direction of fast axes is consistent with the direction of the regional principal stress caused by plate movement. Combined with the azimuthal anisotropy models in the deep crust and uppermost mantle from the surface wave and Pn wave, the different anisotropic patterns caused by the Tan-Lu Fault Zone and its conjugated fault system nearby are shown in the upper and lower crust. Furthermore,by using the double-difference method, we relocated the Lujiang earthquake series, which contained 32 earthquakes with a depth shallower than 10 km. Both the Vs model and earthquake relocation results indicate that earthquakes mostly occurred in the vicinity of structural boundaries with fractured media, with high-level development of cracks and small-scale faults jammed between more rigid areas. 展开更多
关键词 ambient noise tomography azimuthal anisotropy upper crust seismogenic structure the Tan-Lu Fault Zone Hefei segment
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Angular vibration analysis of a plane grating monochromator at the Hefei Advanced Light Facility
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作者 Xiang Zhong Jixia Yi +6 位作者 Xinyu Lian Huaxia Deng Guanghui Han Mengchao Ma Yang Peng Shen Wei Xinglong Gong 《Theoretical & Applied Mechanics Letters》 2025年第5期421-426,共6页
The stability of the plane grating monochromator in the Hefei Advanced Light Facility is highly important for beamline focusing,with angular vibration being a key indicator for assessing its stability.This paper propo... The stability of the plane grating monochromator in the Hefei Advanced Light Facility is highly important for beamline focusing,with angular vibration being a key indicator for assessing its stability.This paper proposes an elastic fitting method based on fifth-order polynomial fitting for the precise analysis of microangular vibrations on grating surfaces.Compared with the traditional rigid body method,this method fully considers the three major elastic characteristics exhibited by optical components during vibration:significant phase differences,nonuniform deformation gradients,and spatial distribution differences in angular deformation.The research results indicate that this method can accurately reflect the actual vibration state of the grating surface,not only enabling the quantitative prediction of local angular microvibration but also establishing a reliable theoretical analysis framework for the stability assessment of high-precision instruments. 展开更多
关键词 Hefei Advanced Light Facility Dynamic simulations Elastic deformation Local angular microvibration
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Discovery of a Novel Ginseng Polysaccharide:Structure Characterization,in vitro Fermentability and Anti-oxidative Mechanism of Fermented Product via the Nrf2/HO-1 Pathway on Aβ-induced-PC 12 Cells
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作者 DONG Binbin HOU Zong +3 位作者 ZHENG Zhong XING Junpeng LIU Zhiqiang LIU Shu 《高等学校化学学报》 北大核心 2026年第1期173-189,共17页
In this study,a novel polysaccharide GPA-G 2-H was derived from ginseng.Furthermore,the coherent study of its structural characteristics,fermented characteristics in vitro,as well as antioxidant mechanism of fermented... In this study,a novel polysaccharide GPA-G 2-H was derived from ginseng.Furthermore,the coherent study of its structural characteristics,fermented characteristics in vitro,as well as antioxidant mechanism of fermented product FGPA-G 2-H on Aβ25-35-induced PC 12 cells were explored.The structure of GPA-G 2-H was determined by means of zeta potential analysis,FTIR,HPLC,XRD,GC-MS and NMR.The backbone of GPA-G 2-H was mainly composed of→4)-α-D-Glcp-(1→with branches substituted at O-3.Notably,GPA-G 2-H was degraded by intestinal microbiota in vitro with total sugar content and pH value decreasing,and short-chain fatty acids(SCFAs)increasing.Moreover,GPA-G 2-H significantly promoted the proliferation of Lactobacillus,Muribaculaceae and Weissella,thereby making positive alterations in intestinal microbiota composition.Additionally,FGPA-G 2-H activated the Nrf 2/HO-1 signaling pathway,enhanced HO-1,NQO 1,SOD and GSH-Px,while inhabited Keap 1,MDA and LDH,which alleviated Aβ-induced oxidative stress in PC 12 cells.These provide a solid theoretical basis for the further development of ginseng polysaccharides as functional food and antioxidant drugs. 展开更多
关键词 Ginseng polysaccharide Structural characterization Intestinal microbiota FERMENTABILITY Oxidative stress
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Relationship of Non-Essential and Essential Metals with Vitamin D in a Chinese Early Adolescent Cohort
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作者 Gengfu Wang Weibo Liu +9 位作者 Min Li Ting Tang Qi Zhong Guangbo Qu Yi Zhou Mengyuan Yuan Yonghan Li Fangbiao Tao Puyu Su Chaoxue Zhang 《Biomedical and Environmental Sciences》 2026年第1期116-122,共7页
Vitamin D deficiency(VDD)represents a significant nutritional concern among children and adolescents.The estimated prevalence of VDD in China is 46.8%in this population^([1]).VDD during childhood and adolescence has b... Vitamin D deficiency(VDD)represents a significant nutritional concern among children and adolescents.The estimated prevalence of VDD in China is 46.8%in this population^([1]).VDD during childhood and adolescence has been associated with the onset of various conditions,including acute respiratory infections,asthma,atopic dermatitis,and food allergies^([2]).Multiple factors,including age,sun exposure,adiposity,and genetics,influence vitamin D levels^([2,3]).Increasing attention has been directed toward understanding the environmental determinants that may influence vitamin D status.Given the potential of metallic pollutants to disrupt endocrine function and their ubiquity in the environment,investigating the effects of metal exposure on human vitamin D status,particularly in vulnerable populations,is imperative. 展开更多
关键词 vitamin d deficiency vdd represents Chinese early adolescent cohort essential metals vitamin d non essential metals food allergies multiple acute respiratory infectionsasthmaatopic dermatitisand vitamin D deficiency
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Crushing evolution in pebble bed based on a novel method:a crushable DEM study
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作者 Jian Wang Ming‑Zhun Lei +4 位作者 Ming‑Zong Liu Qi‑Gang Wu Zi‑Cong Cai Kai‑Song Wang Hai‑Shun Deng 《Nuclear Science and Techniques》 2026年第1期212-224,共13页
In this paper,a novel method for investigating the particle-crushing behavior of breeding particles in a fusion blanket is proposed.The fractal theory and Weibull distribution are combined to establish a theoretical m... In this paper,a novel method for investigating the particle-crushing behavior of breeding particles in a fusion blanket is proposed.The fractal theory and Weibull distribution are combined to establish a theoretical model,and its validity was verified using a simple impact test.A crushable discrete element method(DEM)framework is built based on the previously established theoretical model.The tensile strength,which considers the fractal theory,size effect,and Weibull variation,was assigned to each generated particle.The assigned strength is then used for crush detection by comparing it with its maximum tensile stress.Mass conservation is ensured by inserting a series of sub-particles whose total mass was equal to the quality loss.Based on the crushable DEM framework,a numerical simulation of the crushing behavior of a pebble bed with hollow cylindrical geometry under a uniaxial compression test was performed.The results of this investigation showed that the particle withstands the external load by contact and sliding at the beginning of the compression process,and the results confirmed that crushing can be considered an important method of resisting the increasing external load.A relatively regular particle arrangement aids in resisting the load and reduces the occurrence of particle crushing.However,a limit exists to the promotion of resistance.When the strain increases beyond this limit,the distribution of the crushing position tends to be isotropic over the entire pebble bed.The theoretical model and crushable DEM framework provide a new method for exploring the pebble bed in a fusion reactor,considering particle crushing. 展开更多
关键词 Crushing behavior Granular material Discrete element method Pebble bed Fractal theory
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Monolithically Integrated Optical Convolutional Processors on Thin Film Lithium Niobate
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作者 Rui-Xue Liu Yong Zheng +5 位作者 Yuan Ren Bo-Yang Nan Yun-Peng Song Rong-Bo Wu Min Wang Ya Cheng 《Chinese Physics Letters》 2026年第1期49-63,共15页
Photonic neural networks(PNNs)of sufficiently large physical dimensions and high operation accuracies are envisaged as ideal candidates for breaking the major bottlenecks in the current artificial intelligence archite... Photonic neural networks(PNNs)of sufficiently large physical dimensions and high operation accuracies are envisaged as ideal candidates for breaking the major bottlenecks in the current artificial intelligence architectures in terms of latency,energy efficiency,and computational power.To achieve this vision,it is of vital importance to scale up the PNNs while simultaneously reducing the high demand on the dimensions required by them.The underlying cause of this strategy is the enormous gap between the scales of photonic and electronic integrated circuits.Here,we demonstrate monolithically integrated optical convolutional processors on thin film lithium niobate(TFLN)that harness inherent parallelism in photonics to enable large-scale programmable convolution kernels and,in turn,greatly reduce the dimensions required by subsequent fully connected layers.Experimental validation achieves high classification accuracies of 96%(86%)on the MNIST(Fashion-MNIST)dataset and 84.6%on the AG News dataset while dramatically reducing the required subsequent fully connected layer dimensions to 196×10(from 784×10)and 175×4(from 800×4),respectively.Furthermore,our devices can be driven by commercial field-programmable gate array systems;a unique advantage in addition to their scalable channel number and kernel size.Our architecture provides a solution to build practical machine learning photonic devices. 展开更多
关键词 photonic neural networks pnns artificial intelligence architectures breaking major bottlenecks monolithic integration LATENCY energy efficiency thin film lithium niobate photonic neural networks
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Low-intensity transcranial ultrasound neuromodulation promotes neuronal regeneration:A new hope for noninvasive treatment of neurodegenerative diseases
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作者 Shu Xia Chen He +4 位作者 Yunfei Li Hao Li Bo Wang Long Xu Xudong Zhao 《Neural Regeneration Research》 2026年第6期2300-2312,共13页
Neurodegenerative diseases,which are characterized by progressive neuronal loss and the lack of disease-modifying therapies,are becoming a major global health challenge.The existing neuromodulation techniques,such as ... Neurodegenerative diseases,which are characterized by progressive neuronal loss and the lack of disease-modifying therapies,are becoming a major global health challenge.The existing neuromodulation techniques,such as deep brain stimulation and transcranial magnetic stimulation,show limitations such as invasiveness,restricted cortical targeting,and irreversible tissue effects.In this context,low-intensity transcranial ultrasound has emerged as a promising noninvasive alternative that can penetrate deep into the brain and modulate neuroplasticity.This review comprehensively assesses the therapeutic mechanisms,efficacy,and translational potential of low-intensity transcranial ultrasound in treating neurodegenerative diseases,with emphasis on its role in promoting neuronal regeneration,modulating neuroinflammation,and enhancing functional recovery.We summarize the findings of previous studies and systematically illustrate the potential of low-intensity transcranial ultrasound in regulating cell death mechanisms,enhancing neural repair and regeneration,and alleviating symptoms associated with neurodegenerative diseases.Preclinical findings indicate that low-intensity transcranial ultrasound can enhance the release of neurotrophic factors(e.g.,brain-derived neurotrophic factor),promote autophagy to clear protein aggregates,modulate microglial activation,and temporarily open the blood-brain barrier to facilitate targeted drug delivery.Existing clinical trial data show that low-intensity transcranial ultrasound can reduce amyloid-βplaques,improve motor and cognitive deficits,and promote remyelination in various disease models.Early clinical trials suggest that low-intensity transcranial ultrasound may enhance cognitive scores in Alzheimer’s disease and alleviate motor symptoms in Parkinson’s disease,all while demonstrating a favorable safety profile.Past studies support the notion that by integrating safety,precision,and reversibility,low-intensity transcranial ultrasound can transform the treatment landscape for neurodegenerative disease.However,more advancements are necessary for future clinical application of low-intensity transcranial ultrasound,including optimizing parameters such as frequency,intensity,and duty cycle;considering individual anatomical differences;and confirming long-term efficacy.We believe establishing standardized protocols,conducting larger trials,and investigating the underlying mechanisms to clarify dose-response relationships and refine personalized application strategies are essential in this regard.Future research should focus on translating preclinical findings into clinical practice,addressing technical challenges,and exploring combination therapies with pharmacological or gene interventions. 展开更多
关键词 Alzheimer’s disease frontotemporal dementia low-intensity transcranial ultrasound multiple sclerosis multiple system atrophy neurodegenerative diseases NEUROMODULATION neuronal regeneration Parkinson’s disease transcranial ultrasound stimulation
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Numerical study of a quantum spin in an s-wave superconductor using the natural orbitals renormalization group method
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作者 Wen-Jing Zhang Ru Zheng +1 位作者 Rong-Qiang He Zhong-Yi Lu 《Chinese Physics B》 2026年第2期538-547,共10页
In a superconductor embedded with a quantum magnetic impurity,the Kondo effect is involved,leading to the competition between the Kondo singlet phase and the superconductivity phase.By means of the natural orbitals re... In a superconductor embedded with a quantum magnetic impurity,the Kondo effect is involved,leading to the competition between the Kondo singlet phase and the superconductivity phase.By means of the natural orbitals renormalization group(NORG)method,we revisit the problem of a quantum magnetic impurity coupled with a conventional s-wave superconductor.Here we present a detailed study focusing on the impurity spin polarization and susceptibility,the Kondo screening cloud,as well as the number and structures of the active natural orbitals(ANOs).In the superconducting phase,the impurity spin is partially polarized,indicating that the impurity remains partially screened by the quantum fluctuations.Furthermore,the impurity spin susceptibility becomes divergent,resulting from the presence of residual local moment formed at the impurity site.Correspondingly,a non-integral(incomplete)Kondo cloud is formed,although the ground state is a spin doublet in this phase.In comparison,the Kondo cloud is complete in the Kondo singlet phase as expected.We also quantify the critical point,where the quantum phase transition from a Kondo singlet phase to a superconducting phase occurs,which is consistent with that in previous works.On the other hand,it is illustrated that only one ANO emerges in both quantum phases.The structures of the ANO,projected into both the real space and momentum space,are distinct in the Kondo singlet phase from that in the superconducting phase.More specifically,in the Kondo singlet phase,the ANO keeps fully active with half-occupied,and the superconducting gap has negligible influence on its structure.On the contrary,in the superconducting phase,the ANO tends to be inactive and its structure changes significantly as the superconducting gap increases.Additionally,our investigation demonstrates that the NORG method is reliable and convenient to solve the quantum impurity problems in superconductors as well,which will promote further theoretical studies on the Kondo problems in such systems using numerical methods. 展开更多
关键词 Kondo effect SUPERCONDUCTOR natural orbitals renormalization group active natural orbitals
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A novel method for EPID transmission dose generation using Monte Carlo simulation and deep learning
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作者 Tao Qiu Ning Gao +3 位作者 Yan-Kui Chang Xi Pei Huan-Li Luo Fu Jin 《Nuclear Science and Techniques》 2026年第4期41-52,共12页
This study aimed to integrate Monte Carlo(MC)simulation with deep learning(DL)-based denoising techniques to achieve fast and accurate prediction of high-quality electronic portal imaging device(EPID)transmission dose... This study aimed to integrate Monte Carlo(MC)simulation with deep learning(DL)-based denoising techniques to achieve fast and accurate prediction of high-quality electronic portal imaging device(EPID)transmission dose(TD)for patientspecific quality assurance(PSQA).A total of 100 lung cases were used to obtain the noisy EPID TD by the ARCHER MC code under four kinds of particle numbers(1×10^(6),1×10^(7),1×10^(8)and 1×10^(9)),and the original EPID TD was denoised by the SUNet neural network.The denoised EPID TD was assessed both qualitatively and quantitatively using the structural similarity(SSIM),peak signal-to-noise ratio(PSNR),and gamma passing rate(GPR)with respect to 1×10^(9)as a reference.The computation times for both the MC simulation and DL-based denoising were recorded.As the number of particles increased,both the quality of the noisy EPID TD and computation time increased significantly(1×10^(6):1.12 s,1×10^(7):1.72 s,1×10^(8):8.62 s,and 1×10^(9):73.89 s).In contrast,the DL-based denoising time remained at 0.13-0.16 s.The denoised EPID TD shows a smoother visual appearance and profile curves,but differences between 1×10^(6)and 1×10^(9)still remain.SSIM improves from 0.61 to 0.95 for 1×10^(6),0.70 to 0.96 for 1×10^(7),and 0.90 to 0.97 for 1×10^(8).PSNR increases by>20%for 1×10^(6)and 1×10^(7),and>10%for 1×10^(8).GPR improves from 48.47%to 89.10%for 1×10^(6),61.04%to 94.35%for 1×10^(7),and 91.88%to 99.55%for 1×10^(8).The method that combines MC simulation with DL-based denoising for EPID TD generation can accelerate TD prediction and maintain high accuracy,offering a promising solution for efficient PSQA. 展开更多
关键词 PSQA EPID Monte Carlo Deep learning
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Asymmetric construction of non-activated C-SCF_(3) stereocenter via copper-catalyzed hydroallylation of SCF_(3)-alkenes
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作者 Wei-Cheng Zhao Yan He +4 位作者 Chen-Hui Jiang Peng Liu Qian Gao Duo-Duo Hu Xi-Sheng Wang 《Chinese Chemical Letters》 2026年第2期424-429,共6页
Fluorinated motifs are prevalent in both pharmaceuticals and agrochemicals.The incorporation of fluorine-containing moieties to drug candidates has emerged as a potent strategy for lead optimization in pharmaceutical ... Fluorinated motifs are prevalent in both pharmaceuticals and agrochemicals.The incorporation of fluorine-containing moieties to drug candidates has emerged as a potent strategy for lead optimization in pharmaceutical research and development.While extensive research has been devoted to constructing molecules that incorporate a trifluoromethylthio(SCF_(3)−)group on a stereogenic carbon,the synthesis of trifluoromethylthiolated alkanes featuring a SCF_(3)-substituted stereogenic carbon at non-activated site remains understudied.Herein,we report a Cu-catalyzed regio-and enantioselective hydroallylation of 1-trifluoromethylthiolated alkenes.Important to the process is the regio-and enantioselective Cu-H insertion to SCF_(3)-substituted alkene to form chiralα-SCF_(3) alkyl copper intermediates,outcompeting unproductive insertion to the coupling partner,and eventually proceed to afford optically active homoallylic trifluoromethylthiolated products. 展开更多
关键词 Asymmetric construction Non-activated Hydroallylation Trifluoromethylthio group COPPER-CATALYZED
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Ultrasound-induced Activation of Tetravalent Platinum Polyglutamate Nanoprodrug Accelerated by Coumarin Derivatives
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作者 Chao-Ying Kong Chu-Wen Luo +2 位作者 Ya-Jun Xu Na Shen Zhao-Hui Tang 《Chinese Journal of Polymer Science》 2026年第1期44-56,I0009,共14页
Given that platinum-based drugs are widely used clinically as chemotherapeutic agents,their severe toxic side effects have attracted significant attention.Consequently,the development of novel nanoprodrugs based on lo... Given that platinum-based drugs are widely used clinically as chemotherapeutic agents,their severe toxic side effects have attracted significant attention.Consequently,the development of novel nanoprodrugs based on low-toxicity tetravalent platinum(Pt(Ⅳ))com plexes holds substantial research value.Herein,we discovered that coumarin derivatives exhibit inherent antitumor efficacy and significantly enhance superoxide anion radicals(·O_(2)^(-))generation in aqueous solutions under ultrasound(US)irradiation.Given that·O_(2)^(-)is known to mediate the reduction of Pt(Ⅳ)to divalent platinum(Pt(Ⅱ)),we engineered an US-responsive dual-drug nanoprodrug(P-cisPt(Ⅳ)@5-MOP).This nanoprodrug was prepared by covalently conjugating Pt(Ⅳ)and methoxy polyethylene glycol hydroxyl(m PEG-OH)to a poly(_(L)-glutamic acid)(PLG)carrier,followed by encapsulating coumarin derivatives.Under low-intensity US irradiation(1.5 W/cm^(2),1 MHz,10 min),P-cisPt(Ⅳ)@5-MOP achieved a Pt(Ⅳ)reduction rate of 91.4%.Furthermore,upon US exposure,its half-maximal inhibitory concentration(IC_(50))against 4T1 breast cancer cells decreased dramatically from 25.7μmol/L to 0.1μmol/L.Remarkably,this system combined with US therapy yielded a tumor inhibition rate of 90.9%,with 40%of tumor-bea ring mice achieving com plete eradication of tumors,while exhibiting low systemic toxicity.Collectively,this work not only identifies a novel sonosensitizer capable of generating·O_(2)^(-)but also develops a new class of ultrasound-activatable Pt(Ⅳ)nanoprodrug. 展开更多
关键词 Ultrasound activation Ultrasound chemistry Platinum drug COUMARIN Superoxide anion radical
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Assessing the photoluminescence of metal nanoclusters:The individual versus the collective
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作者 Xiaoqin Du Peiyao Pan +4 位作者 Haoqi Li Di Zhang Wentao Huang Xi Kang Manzhou Zhu 《Chinese Chemical Letters》 2026年第2期559-563,共5页
Understanding the photoluminescence(PL)mechanism of metal nanoclusters from both molecular and supramolecular perspectives is crucial for developing highly emissive cluster-based nanomaterials.In this study,we synthes... Understanding the photoluminescence(PL)mechanism of metal nanoclusters from both molecular and supramolecular perspectives is crucial for developing highly emissive cluster-based nanomaterials.In this study,we synthesized two structurally similar Ag14 nanoclusters with different phosphine stabilizers,which demonstrated opposite PL behaviors in solution and crystalline states.The Ag14 nanocluster stabilized by P(Ph-OMe)_(3) ligands exhibited a higher PL intensity compared to the one stabilized by P(Ph-F)_(3) ligands,which was attributed to the stronger electron-donating ability of the P(Ph-OMe)_(3) ligand that improved ligand-to-metal charge transfer efficiency.In contrast,the P(Ph-F)_(3) stabilized Ag14 crystals displayed greater PL intensity than the Ag14 cluster crystal with a-OMe surface,which was due to stronger intermolecular interactions within the cluster lattice of the former that limited non-radiative energy loss and thus enhanced PL.Overall,this work aims to promote a comprehensive understanding of the fluorescence in cluster-based nanomaterials,which will be beneficial for their downstream applications. 展开更多
关键词 NANOCLUSTER PHOTOLUMINESCENCE Crystal structure Ligand effect Intermolecular interaction
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Between Themis and Prometheus:a history of the ethics of science and technology
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作者 Jia-Yun Chen Zong-Zhen Wu +7 位作者 Qiang-Yu Xiang Lu Zhang Jia-Lin Diao Ya-Hui Zhang Shen-Shen Yan Kun-Lan Zuo Jian-Liang Huang Huan Liu 《History and Philosophy of Medicine》 2026年第1期49-59,共11页
Background:With the rapid development of modern emerging technologies,the ethical dilemmas and social controversies triggered by scientific and technological activities have become increasingly prominent.How to guide ... Background:With the rapid development of modern emerging technologies,the ethical dilemmas and social controversies triggered by scientific and technological activities have become increasingly prominent.How to guide technology for good and prevent and control technological risks has become an important issue of global concern.Research on science and technology ethics is dedicated to integrating ethical theories into governance practices and constructing ethical models that adapt to the development of the times.Methods:This article systematically reviews the six core approaches of scientific and technological ethics thought,including technological autonomy and political philosophy criticism,responsibility ethics and intergenerational obligations,technological intermediation and the integration of life and the world,ethical principles and normative frameworks,participatory governance and ethical practice innovation,as well as domain-specific ethical norms,thereby constructing an ethical analysis framework applicable to medical technology risks.And cross-analysis was conducted by taking medical events such as gene editing and xenotransplantation as examples.Results:Research shows that a single ethical approach has limitations in addressing complex medical ethical challenges,while the six approaches are complementary and synergistic.By criticizing technological autonomy,establishing a responsibility ethics orientation,setting the bottom line of ethical principles,promoting participatory governance,formulating domain norms,and continuously reflecting on the intermediary nature of technology,a multi-level and dynamically adaptive governance system for scientific and technological ethics can be constructed.Conclusion:The key to addressing contemporary medical ethics challenges lies in the comprehensive application of science and technology ethics theories and the integration of ethical considerations throughout the entire process of scientific and technological research and development.In the future,a governance framework that adapts to the development of new technologies should be established to promote cross-cultural and cross-disciplinary ethical dialogue and public participation,ensuring that scientific and technological innovation always serves the dignity of human life and overall well-being. 展开更多
关键词 ethics of science and technology history of science ethical governance responsible innovation medical ethics
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Ultrathin Gallium Nitride Quantum-Disk-in-Nanowire-Enabled Reconfigurable Bioinspired Sensor for High-Accuracy Human Action Recognition
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作者 Zhixiang Gao Xin Ju +10 位作者 Huabin Yu Wei Chen Xin Liu Yuanmin Luo Yang Kang Dongyang Luo JiKai Yao Wengang Gu Muhammad Hunain Memon Yong Yan Haiding Sun 《Nano-Micro Letters》 2026年第2期439-453,共15页
Human action recognition(HAR)is crucial for the development of efficient computer vision,where bioinspired neuromorphic perception visual systems have emerged as a vital solution to address transmission bottlenecks ac... Human action recognition(HAR)is crucial for the development of efficient computer vision,where bioinspired neuromorphic perception visual systems have emerged as a vital solution to address transmission bottlenecks across sensor-processor interfaces.However,the absence of interactions among versatile biomimicking functionalities within a single device,which was developed for specific vision tasks,restricts the computational capacity,practicality,and scalability of in-sensor vision computing.Here,we propose a bioinspired vision sensor composed of a Ga N/Al N-based ultrathin quantum-disks-in-nanowires(QD-NWs)array to mimic not only Parvo cells for high-contrast vision and Magno cells for dynamic vision in the human retina but also the synergistic activity between the two cells for in-sensor vision computing.By simply tuning the applied bias voltage on each QD-NW-array-based pixel,we achieve two biosimilar photoresponse characteristics with slow and fast reactions to light stimuli that enhance the in-sensor image quality and HAR efficiency,respectively.Strikingly,the interplay and synergistic interaction of the two photoresponse modes within a single device markedly increased the HAR recognition accuracy from 51.4%to 81.4%owing to the integrated artificial vision system.The demonstration of an intelligent vision sensor offers a promising device platform for the development of highly efficient HAR systems and future smart optoelectronics. 展开更多
关键词 GaN nanowire Quantum-confined Stark effect Voltage-tunable photoresponse Bioinspired sensor Artificial vision system
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Insights into the organic acid and flavonoid metabolisms in moderately withered blueberries based on metabolomics and transcriptomics
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作者 Qin Yang Haijun Bi +6 位作者 Qi Zhang Shuqin Huang Chen Bian Lulu Zhao Hongbin Chen Xueling Gao Yu Wang 《Journal of Future Foods》 2026年第6期1155-1165,共11页
This study employed integrated metabolomic and transcriptomic analyses to investigate the impacts of moderate withering(approximately 30%weight loss)on organic acid and flavonoid accumulation in blueberries and the re... This study employed integrated metabolomic and transcriptomic analyses to investigate the impacts of moderate withering(approximately 30%weight loss)on organic acid and flavonoid accumulation in blueberries and the resultant blueberry wines.Moderate withering led to decreases in aliphatic organic acids but increases in phenolic acids and flavonoids in blueberries.The decrease in malate could be linked to the downregulated VcMDH and VcDTC,and the decrease in citrate and 2-oxoglutarate could be a consequence of y-aminobutyric acid shunt activation.The increases of phenolic acids were associated with upregulated VcCAD and VcPOD in withered blueberries.Additionally,moderate withering upregulated the expression of VcLAR and VcUFGT,promoting flavonoid accumulation.In blueberry wines,moderate withering decreased total aliphatic organic acid content but increased anthocyanin content,consistent with the findings in blueberries.Overall,this study provided references for applying moderate withering in blueberry winemaking,contributing to modulating acidity and enriching phenolic substances. 展开更多
关键词 BLUEBERRY Moderate withering Wine Organic acids Flavonoids
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Synergistic triple-site engineering in ABX_(3)-type hybrid halides for high-performance nonlinear optical crystals
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作者 Yuwei Kang Can Yang +1 位作者 Jun Zhang Qi Wu 《Chinese Chemical Letters》 2026年第1期666-670,共5页
Achieving non-centrosymmetric(NCS) configurations in ABX3-type hybrid halides remains a critical challenge for nonlinear optical(NLO) materials due to the conflicting requirements of high second-harmonic generation(SH... Achieving non-centrosymmetric(NCS) configurations in ABX3-type hybrid halides remains a critical challenge for nonlinear optical(NLO) materials due to the conflicting requirements of high second-harmonic generation(SHG) response,wide bandgap,and phase-matching capabilities.Herein,we propose a triplesite modulation strategy by synergistically tailoring the A-site cations(2-methylimidazole cation/1-ethyl-3-methylimidazole cation),B-site metals(Sn^(2+)/Pb^(2+)),and X-site halogens(Cl/Br),which effectively disrupts lattice symmetry and enables NCS crystallization.Our results demonstrate a strong SHG response,an expanded optical bandgap and increased birefringence.The optimized compound C_(6)H_(11)N_(2)PbCl_(3) exhibits a moderately strong SHG efficiency of 3.8 × KDP,a wide bandgap(3.87 eV),and enhanced birefringence(0.139@1064 nm),surpassing majority hybrid NLO materials.The innovative anionic framework introduced here broadens the scope of hybrid NLO crystals,facilitating the integration of various aromatic heterocyclic cations.This research provides a robust strategic framework for the development of advanced NLO materials. 展开更多
关键词 Nonlinear Optical organic-inorganic hybrid ABX_(3)lone pair Optimized balance
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Combined multidetector computed tomography and gastrointestinal endoscopy for gastric cancer screening,preoperative staging,and lymph node metastasis detection
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作者 Le-Ping Ye Yan-Ping Zhang +4 位作者 Gang Chen Yi-Xian Wu Cheng-Long He Dong Wang Qiao Mei 《World Journal of Gastrointestinal Oncology》 2026年第1期200-210,共11页
BACKGROUND Early screening,preoperative staging,and diagnosis of lymph node metastasis are crucial for improving the prognosis of gastric cancer(GC).AIM To evaluate the diagnostic value of combined multidetector compu... BACKGROUND Early screening,preoperative staging,and diagnosis of lymph node metastasis are crucial for improving the prognosis of gastric cancer(GC).AIM To evaluate the diagnostic value of combined multidetector computed tomography(MDCT)and gastrointestinal endoscopy for GC screening,preoperative staging,and lymph node metastasis detection,thereby providing a reference for clinical diagnosis and treatment.METHODS In this retrospective study clinical and imaging data of 134 patients with suspected GC who were admitted between January 2023 and October 2024 were initially reviewed.According to the inclusion and exclusion criteria,102 patients were finally enrolled in the analysis.All enrolled patients had undergone both MDCT and gastrointestinal endoscopy examinations prior to surgical intervention.Preoperative clinical staging and lymph node metastasis findings were compared with pathological results.RESULTS The combined use of MDCT and gastrointestinal endoscopy demonstrated a sensitivity of 98.53%,specificity of 97.06%,accuracy of 98.04%,positive predictive value of 98.53%,and negative predictive value of 97.06%for diagnosing GC.These factors were all significantly higher than those of MDCT or endoscopy alone(P<0.05).The accuracy rates of the combined approach for detecting clinical T and N stages were 97.06%and 92.65%,respectively,outperforming MDCT alone(86.76% and 79.41%)and endoscopy alone(85.29% and 70.59%)(P<0.05).Among 68 patients with confirmed GC,50(73.53%)were pathologically diagnosed with lymph node metastasis.The accuracy for detecting lymph node metastasis was 66.00%with endoscopy,76.00%with MDCT,and 92.00% with the combined approach,all with statistically significant differences(P<0.05).CONCLUSION The combined application of MDCT and gastrointestinal endoscopy enhanced diagnostic accuracy for GC,provided greater consistency in preoperative staging,and improved the detection of lymph node metastasis,thereby demonstrating significant clinical utility. 展开更多
关键词 Multidetector computed tomography Gastrointestinal endoscopy Gastric cancer Preoperative staging Lymph node metastasis
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Synergistic fluorinated and non-fluorinated solvents for electrolytes of lithium-ion batteries at low temperatures
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作者 Xuning Gao Nan Piao +7 位作者 Yukun Yan Jinghao Wang Haolun Zou Siqi Guan Leiying Zeng Zhenhua Sun Guangjian Hu Feng Li 《Chinese Chemical Letters》 2026年第2期582-587,共6页
Commercial carbonate electrolytes suffer from ion transport difficulty in bulk electrolytes and interphase at low temperatures,bringing challenges to the application of lithium-ion batteries(LIBs)at low temperatures.H... Commercial carbonate electrolytes suffer from ion transport difficulty in bulk electrolytes and interphase at low temperatures,bringing challenges to the application of lithium-ion batteries(LIBs)at low temperatures.Herein,the ester solvent of methyl propionate(MP)with low melting point and low viscosity was used to tackle ion transport difficulty in electrolytes.Fluorinated ester was further added to accelerate interfacial transport through intermolecular interactions.The influence of fluorinated esters with different fluorination degrees on the solvation structure of electrolytes and the performance of batteries was further studied.As a result,methyl pentafluoropropionate(M5F)with five fluorine atoms was selected for its optimal interactions with both Li+and MP solvent in the primary solvation structure,contributing to desired solvation structure for fast interfacial transport.The LiFePO4(LFP)||graphite cell with LiFSI-MP-M5F electrolyte exhibited a high cyclability of 85.8%after 120 cycles and retained 81.2%of room-temperature capacity when charged and discharged at−30℃.1 Ah LFP||graphite pouch cell with high cathode loading(20 mg/cm^(2))in LiFSI-MP-M5F electrolyte exhibited 0.85 Ah capacity when charged and discharged at−20℃.This work provides a guidance for electrolyte design by synergistic fluorinated and non-fluorinated solvents for LIBs at low-temperature application. 展开更多
关键词 Lithium-ion batteries ELECTROLYTE Fluorinated solvent Non-fluorinated solvent Solvation structure Low temperatures
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