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High-precision X-ray polarimeter based on channel-cut crystals

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Nuclear Science and Techniques 2024年第3期35卷 30-39页

作者： Shang-Yu Si zhong-liang li Wen-Hong jia lian Xue Hong-Xin Luo jian-Cai Xu Bai-Fei Shen lin-Gang Zhang liang-liang Ji Yu-Xin Leng Ren-zhong Tai Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800China

We report on using synthetic silicon for a high-precision X-ray polarimeter comprising a polarizer and an analyzer,each based on a monolithic channel-cut crystal used at multiple Brewster reflections with a Bragg angle very close to 45°.Experiments were performed at the BL09B bending magnet beamline of the Shanghai Synchrotron Radiation Facility using a Si(800)crystal at an X-ray energy of 12.914 keV.A polarization purity of 8.4×10^(-9)was *** result is encouraging,as the measured polarization purity is the best-reported value for the bending magnet ***,this is the firstly systematic study on the hard X-ray polarimeter in China,which is crucial for exploring new physics,such as verifying vacuum birefringence.

关键词： X-ray polarimeter Vacuum birefringence Synchrotron radiation Channel-cut crystal

横场中具有周期性各向异性的一维XY模型的量子相变

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物理学报 2017年第18期66卷 47-54页

作者：宋加丽钟鸣童培庆南京师范大学物理科学与技术学院南京210023 江苏省大规模复杂系统数值模拟重点实验室南京210023

通过解析和数值计算的方法研究了横场中具有周期性各向异性的一维XY自旋模型的量子相变和量子纠缠.主要讨论了周期为二的情况,即各向异性参数交替地取比值为α的两个值.结果表明,与横场中均匀XY模型相比,α=-1所对应的模型在参数空间的... 详细信息

通过解析和数值计算的方法研究了横场中具有周期性各向异性的一维XY自旋模型的量子相变和量子纠缠.主要讨论了周期为二的情况,即各向异性参数交替地取比值为α的两个值.结果表明,与横场中均匀XY模型相比,α=-1所对应的模型在参数空间的相图存在着明显的不同.原来的Ising相变仍然存在,没有了沿x和y方向的各向异性铁磁(FM_x,FM_y)相,即各向异性相变消失,出现了一个新的相,并且该相内沿x和y方向的长程关联函数相等且大于零,我们称新相为各向同性铁磁(FM_(xx))相.这是由于系统新的对称性所导致的.解析结果还说明系统在FM_(xx)相中的单粒子能谱有两个零点,是一个无能隙的相.最后,利用冯·诺依曼熵数值地研究了系统在新相内各点的量子纠缠,发现该相内每一点的冯·诺依曼熵的标度行为与均匀XY模型在各向异性相变处的相似,即S_L～1/3㏒_2L+Const.

关键词：周期性各向异性XY模型量子相变各向同性铁磁相冯·诺依曼熵

The evolution and functional divergence of 10 Apolipoprotein D-like genes in Nilaparvata lugens

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Insect Science 2024年第1期31卷 91-105页

作者： jia-Bao Lu Peng-Peng Ren Qiao li Fang He zhong-Tian Xu Sai-Nan Wang jian-Ping Chen Jun-Min li Chuan-Xi Zhang Citrus Research Institute Southwest University/Chinese Academy of Agricultural SciencesNational Engineering Research Center for CitrusChongqingChina Technology Center of Wuhan Customs District HubeiChina Institute of Insect Science Zhejiang UniversityHangzhouChina

Apolipoprotein D(ApoD),a member of the lipocalin superfamily of proteins,is involved in lipid transport and stress *** only a single copy of the ApoD gene is found in humans and some other vertebrates,there are typically several ApoD-like genes in *** date,there have been relatively few studies that have examined the evolution and functional differentiation of ApoD-like genes in insects,particularly hemi-metabolous *** this study,we identified 10 ApoD-like genes(NlApoD1−10)with distinct spatiotemporal expression patterns in Nilaparvata lugens(BPH),which is an important pest of ***1−10 were found to be distributed on 3 chromosomes in a tandem array of NlApoD1/2,NlApoD3−5,and NlApoD7/8,and show sequence and gene structural divergence in the coding regions,indicating that multiple gene duplication events occurred during *** analysis revealed that NlApoD1−10 can be clustered into 5 clades,with NlApoD3−5 and NlApoD7/8 potentially evolving exclusively in the Delphacidae *** screening using an RNA interference approach revealed that only NlApoD2 was essential for BPH development and survival,whereas NlApoD4/5 are highly expressed in testes,and might play roles in ***,stress response analysis revealed that NlApoD3−5/9,NlApoD3−5,and NlApoD9 were up-regulated after treatment with lipopolysaccharide,H2O2,and ultraviolet-C,respectively,indicating their potential roles in stress resistance.

关键词： Apolipoprotein D BPH evolution functional divergence gene duplication NIApoD

Transforming Adolescent Smiles:Correcting Skeletal Mandibular Retrusion and Bimaxillary Protrusion with Clear Aligners

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Current Medical Science 2024年第3期44卷 657-666页

作者： Wen-jie FAN jia-qi ZHANG jia-qi ZHAN li HU li-li CHEN Department of Stomatology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430022China School of Stomatology Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Wuhan National High Magnetic Field Center Wuhan430074China The Affiliated lianyungang Hospital of Xuzhou Medical University/The First People’s Hospital of lianyungang Lianyungang222000China The First Affiliated Hospital of Kangda College of Nanjing Medical University/The First People’s Hospital of lianyungang Lianyungang222000China

Maxillary protrusion combined with mandibular retraction is a highly prevalent but extremely complex maxillofacial deformity that can have a serious negative impact on patients’facial aesthetics and mental *** traditional orthodontic treatment strategy often involves extracting 4 first premolars and conventional fixed techniques,combined with mini-implant screws,to retract the anterior teeth and improve facial *** recent years,an invisible orthodontic technique,without brackets,has become increasingly ***,while an invisible aligner has been used in some cases with reasonable results,there remain significant challenges in achieving a perfect *** case report presents an adolescent patient with bimaxillary protrusion and mandibular *** on the characteristics of the invisible aligners and the growth characteristics of the adolescent’s teeth and jawbone,we designed precise three-dimensional tooth movement and corresponding resistance/over-correction for each tooth,while utilizing the patient’s jawbone growth potential to promote rapid development of the mandible,accurately and efficiently correcting bimaxillary protrusion and skeletal mandibular *** patient’s facial aesthetics,especially the lateral morphology,have been greatly improved,and various aesthetic indicators have also shown significant changes,and to the patient’s great benefit,invasive mini-implant screws were not used during the *** case highlights the advantages of using invisible aligners in adolescent maxillary protrusion combined with mandibular retraction ***,comprehensive and accurate design combined with good application of growth potential can also enable invisible orthodontic technology to achieve perfect treatment effects in tooth extractions,providing clinical guidance for orthodontists.

关键词： mandibular retrusion esthetic orthodontic treatment clear aligners growth potential

Enhancing Image Description Generation through Deep Reinforcement Learning:Fusing Multiple Visual Features and Reward Mechanisms

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Computers, Materials & Continua 2024年第2期78卷 2469-2489页

作者： Yan li Qiyuan Wang Kaidi jia School of Cyber Security Gansu University of Political Science and LawLanzhou730070China

Image description task is the intersection of computer vision and natural language processing,and it has important prospects,including helping computers understand images and obtaining information for the visually *** study presents an innovative approach employing deep reinforcement learning to enhance the accuracy of natural language descriptions of *** method focuses on refining the reward function in deep reinforcement learning,facilitating the generation of precise descriptions by aligning visual and textual features more *** approach comprises three key ***,it utilizes Residual Network 101(ResNet-101)and Faster Region-based Convolutional Neural Network(Faster R-CNN)to extract average and local image features,respectively,followed by the implementation of a dual attention mechanism for intricate feature ***,the Transformer model is engaged to derive contextual semantic features from textual ***,the generation of descriptive text is executed through a two-layer long short-term memory network(LSTM),directed by the value and reward *** with the image description method that relies on deep learning,the score of Bilingual Evaluation Understudy(BLEU-1)is 0.762,which is 1.6%higher,and the score of BLEU-4 is ***-based Image Description Evaluation(CIDEr)scored 0.998,Recall-Oriented Understudy for Gisting Evaluation(ROUGE)scored 0.552,the latter improved by 0.36%.These results not only attest to the viability of our approach but also highlight its superiority in the realm of image *** research can explore the integration of our method with other artificial intelligence(AI)domains,such as emotional AI,to create more nuanced and context-aware systems.

关键词： Image description deep reinforcement learning attention mechanism

Towards imbalanced motion:part-decoupling network for video portrait segmentation

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Science China(Information Sciences) 2024年第7期67卷 197-210页

作者： Tianshu YU Changqun XIA jia li State Key Laboratory of Virtual Reality Technology and Systems School of Computer Science and EngineeringBeihang University Peng Cheng Laboratory

Video portrait segmentation(VPS), aiming at segmenting prominent foreground portraits from video frames, has received much attention in recent years. However, the simplicity of existing VPS datasets leads to a limitation on extensive research of the task. In this work, we propose a new intricate large-scale multi-scene video portrait segmentation dataset MVPS consisting of 101 video clips in 7 scenario categories,in which 10843 sampled frames are finely annotated at the pixel level. The dataset has diverse scenes and complicated background environments, which is the most complex dataset in VPS to our best *** the observation of a large number of videos with portraits during dataset construction, we find that due to the joint structure of the human body, the motion of portraits is part-associated, which leads to the different parts being relatively independent in motion. That is, the motion of different parts of the portraits is imbalanced. Towards this imbalance, an intuitive and reasonable idea is that different motion states in portraits can be better exploited by decoupling the portraits into parts. To achieve this, we propose a part-decoupling network(PDNet) for VPS. Specifically, an inter-frame part-discriminated attention(IPDA)module is proposed which unsupervisedly segments portrait into parts and utilizes different attentiveness on discriminative features specified to each different part. In this way, appropriate attention can be imposed on portrait parts with imbalanced motion to extract part-discriminated correlations, so that the portraits can be segmented more accurately. Experimental results demonstrate that our method achieves leading performance with the comparison to state-of-the-art methods.

关键词： video portrait segmentation imbalanced motion unsupervised part decoupling motion correlation inter-frame attention

Association between the cumulative triglyceride-glucose index and the recurrence of atrial fibrillation after radiofrequency catheter ablation

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Journal of Geriatric Cardiology 2024年第2期21卷 200-210页

作者： Qing YAN jia-Qi liANG Yi-De YUAN Yuan li jia-li FAN Wen-Huan WU Pan XU jia-Hong XUE Department of Cardiovascular Medicine the Second Affiliated Hospital of Xi’an Jiaotong UniversityShaanxiChina Department of Cardiovascular Medicine Zichang People’s HospitalShaanxiChina Department of Ultrasound Xijing HospitalAir Force Military Medical UniversityShaanxiChina

BACKGROUND Triglyceride-glucose(TyG)index values are a new surrogate marker for insulin *** study aimed to explore the relationship between cumulative TyG index values and atrial fibrillation(AF)recurrence after radiofrequency catheter ablation(RFCA).METHODS A total of 576 patients with AF who underwent RFCA at the Second Affiliated Hospital of Xi'an jiaotong University were included in this *** participants were grouped based on cumulative TyG index values tertiles within 3 months after *** regression and restricted cubic spline analyses were used to determine the relationship between cumulative TyG index values and AF *** predictive value of all risk factors was assessed by receiver operating curve *** There were 375 patients completed the study(age:63.23±10.73 years,64.27%male).The risk of AF recurrence increased with increasing cumulative TyG index values *** adjusting for potential confounders,patients in the medium cumulative TyG index group[hazard ratio(HR)=4.949,95%CI:1.778–13.778,P=0.002]and the high cumulative TyG index group(HR=8.716,95%CI:3.371–22.536,Pline regression model also showed an increased risk of AF recurrence with increasing cumulative TyG index *** considering cumulative TyG index values,left atrial diameter,and lactate dehydrogenase levels as a comprehensive factor,the model could effectively predict AF recurrence after RFCA[area under the curve(AUC)=0.847,95%CI:0.797–0.897,P<0.001].CONCLUSIONS Cumulative TyG index values were a risk factor for AF recurrence after *** longitudinal TyG index values may assist with optimized for risk stratification and outcome prediction for AF recurrence.

关键词： atrial fibrillation index

mRNA vaccine technology for infectious diseases and beyond

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Science China life Sciences 2024年第10期67卷 2267-2270页

作者： Pei Hao Xiao li Xuan li Wu zhong Key Laboratory of Molecular Virology and Immunology Shanghai Institute of Immunity and InfectionChinese Academy of Sciences University of Chinese Academy of Sciences Changchun Veterinary Research Institute Chinese Academy of Agricultural Sciences Key Laboratory of Synthetic Biology CAS Center for Excellence in Molecular Plant SciencesInstitute of Plant Physiology and EcologyChinese Academy of Sciences National Engineering Research Center for the Emergency Drug Beijing Institute of Pharmacology and Toxicology

The rise of mRNA vaccine technology Vaccines stand as one of the most significant medical advancements, playing a crucial role in the prevention of infectious diseases and the improvement of global health. The triumph of smallpox vaccination stands as a towering achievement in the annals of healthcare, leading to the complete elimination of a oncedevastating disease and showcasing the efficacy of vaccination methods.

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Designing hierarchical structures for innovative cooling textile

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Nano Research 2024年第10期17卷 9202-9224页

作者： Xiran Du Jinlei li Bin Zhu jia Zhu National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesJiangsu Key Laboratory of Artificial Functional MaterialsNanjing UniversityNanjing 210023China School of Sustainable Energy and Resources Nanjing UniversitySuzhou 215163China

The potential of personal cooling technologies in reducing air conditioning energy consumption and enhancing human thermal comfort is *** review focuses on recent advancements in hierarchical structure design for innovative cooling *** with insights into fundamental heat transfer processes between the human body,textile,and the surroundings,we uncover key control *** the advanced hierarchical structure designs enabling effective radiation,sweat evaporation,conduction management,and integration of cold energy sources for realizing effective human body cooling are systematically ***,we explore multifunctional designs beyond cooling,including switchable cooling-heating and ***,we engage in discussions on unifying cooling performance tests and additional multiple requirements to make strides toward practical *** review is anticipated to be a valuable resource,providing the scientific and industrial communities with a quick grasp of past advancements,current challenges,and future directions in achieving effective human body cooling.

关键词： thermal comfort personal cooling textile hierarchical structures