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Towards the performance limit of catenary meta-optics via field-driven optimization

Opto-Electronic Advances 2024年第5期7卷 33-42页

作者： Siran Chen Yingli ha Fei Zhang Mingbo Pu hanlin Bao Mingfeng Xu Yinghui Guo Yue Shen Xiaoliang Ma Xiong Li Xiangang Luo National Key Laboratory of Optical Field Manipulation Science and Technology Chinese Academy of SciencesChengdu 610209China State Key Laboratory of Optical Technologies on Nano-Fabrication and Micro-Engineering Institute of Optics and ElectronicsChinese Academy of SciencesChengdu 610209China College of Materials Science and Opto-Electronic Technology University of Chinese Academy of SciencesBeijing 100049China research Center on Vector Optical Fields Institute of Optics and ElectronicsChinese Academy of SciencesChengdu 610209China Department of Electrical and Computer Engineering University of California Los Angeles(UCLA)Los AngelesCalifornia 90095USA

Catenary optics enables metasurfaces with higher efficiency and wider bandwidth,and is highly anticipated in the imaging system,super-resolution lithography,and broadband ***,the periodic boundary approximation without considering aperiodic electromagnetic crosstalk poses challenges for catenary optical devices to reach their performance ***,perfect control of both local geometric and propagation phases is realized through field-driven optimization,in which the field distribution is calculated under real boundary *** from other optimization methods requiring a mass of iterations,the proposed design method requires less than ten iterations to get the efficiency close to the optimal *** on the library of shape-optimized catenary structures,centimeter-scale devices can be designed in ten seconds,with the performance improved by ~15%.Furthermore,this method has the ability to extend catenary-like continuous structures to arbitrary polarization,including both linear and elliptical polarizations,which is difficult to achieve with traditional design *** provides a way for the development of catenary optics and serves as a potent tool for constructing high-performance optical devices.

关键词： catenary optics catenary structures field-driven optimization

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新兴和发展中经济体的资本管制与美国货币政策的传导

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新金融 2024年第4期 21-28,36页

作者： Jongrim ha haiqin Liu John rogers 李丽丽(译) 周正铭(译) 世界银行复旦大学不详

与发达经济体相比,新兴市场和发展中经济体(EMDEs)的资产收益波动性要大得多。学术界对此现象的研究结果是“各国无法从全球金融周期中脱钩”。文章利用1995—2019年间78个国家的结构向量自回归模型,以及文献中识别美国货币政策冲击的... 详细信息

与发达经济体相比,新兴市场和发展中经济体(EMDEs)的资产收益波动性要大得多。学术界对此现象的研究结果是“各国无法从全球金融周期中脱钩”。文章利用1995—2019年间78个国家的结构向量自回归模型,以及文献中识别美国货币政策冲击的不同方法,检验了资本账户开放程度较低的国家对美国货币政策冲击的系统性反应小于资本管制宽松的国家这一命题。文章还考虑了汇率制度和外汇干预等其他制度特征在解释各国对冲击的反应差异方面的作用。实证结果表明:较严格的资本管制会使利率和汇率对美国货币政策冲击的反应较小,该结果在新兴市场经济国家中更为显著;只有微弱的证据表明汇率的灵活程度会影响美国对外国利率和汇率的溢出效应。本刊编译此篇世界银行的研究报告,以飨读者。

关键词：资本管制溢出效应资本流动管理全球金融周期美联储

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Predicting 3D radiotherapy Dose-Volume Based on Deep Learning

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Intelligent Automation & Soft Computing 2024年第2期39卷 319-335页

作者： Do Nang Toan Lam Thanh Hien ha Manh Toan Nguyen Trong Vinh Pham Trung Hieu Institute of Information Technology Vietnam Academy of Science and TechnologyHanoi10072Vietnam Faculty of Information Technology Lac Hong UniversityBien HoaDong Nai76120Vietnam

Cancer is one of the most dangerous diseaseswith *** of the principal treatments is radiotherapy by using radiation beams to destroy cancer cells and this workflow requires a lot of experience and skill from doctors and *** our study,we focused on the 3D dose prediction problem in radiotherapy by applying the deeplearning approach to computed tomography(CT)images of cancer *** image data has more complex characteristics than normal image data,and this research aims to explore the effectiveness of data preprocessing and augmentation in the context of the 3D dose prediction *** proposed four strategies to clarify our hypothesis in different aspects of applying data preprocessing and *** strategies,we trained our custom convolutional neural network model which has a structure inspired by the u-net,and residual blocks were also applied to the *** output of the network is added with a rectified linear unit(re-Lu)function for each pixel to ensure there are no negative values,which are absurd with radiation *** experiments were conducted on the dataset of the Open Knowledge-Based Planning Challenge which was collected from head and neck cancer patients treatedwith radiation *** results of four strategies showthat our hypothesis is rational by evaluating metrics in terms of the Dose-score and the Dose-volume histogram score(DVH-score).In the best training cases,the Dose-score is 3.08 and the DVH-score is *** addition,we also conducted a comparison with the results of another study in the same context of using the loss function.

关键词： CT image 3D dose prediction data preprocessing augmentation

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Old-growth mixed dipterocarp forests show variable losses and gains in aboveground biomass and standing carbon over forty years

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Forest Ecosystems 2024年第1期11卷 14-23页

作者： Sisira Ediriweera Champika Bandara Tithira Lakkana Shanika Jayasinghe David Woodbury Arun Dayanandan B.M.P.Singhakumara Xiangcheng Mi I.A.u.N.Gunatilleke C.V.S.Gunatilleke Mark SAshton Department of Science and Technology Uva Wellassa UniversityBadullaSri Lanka The Forest School Yale School of the EnvironmentYale UniversityNew HavenCT06511USA Department of Forestry and Environmental Science University of Sri JayewardenepuraNugegodaSri Lanka State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing100093China Botany Department University of PeradeniyaPeradeniyaSri Lanka

Background:No studies have documented long-term trends in aboveground biomass(AGB)for mixed-dipterocarp forests(MDF),the dominant rain forest type in tropical wet equatorial *** our study,we sought to document such trends over forty years across three sites representing lowland to lower montane ***:To do this,we established fifty 100 m×25 m plots in 1978 across three sites sampled along an elevation gradient,identified as mature old-growth *** measured trees for diameter at breast height that we identified to species and *** took wood samples to calculate species wood-specific *** re-measured plots in 1998 and again in ***:We show standing AGB for all sites combined to be 517.52 Mg·ha^(-1)in 1978,but this declined by 17%over 40 years to 430.11 Mg·ha^(-1).No differences exist among sites in AGB primarily because of considerable within site variation;but interactions of time with site show declines across sites were not uniform,one remained about the *** few species represented a high proportion of the AGB with the top five species comprising between 34%and 65%,depending upon site and year *** species,Mesua nagassarium,represented a disproportionately large amount of AGB and decline over time,particularly at the low elevation ***:Our results are directly relevant to estimating AGB and standing carbon sequestered in *** study is the first to demonstrate varying but overall,declining trends in amounts of AGB among forests making predictions of biomass and standing carbon in MDF difficult over wide regions.

关键词： Western ghats Shorea spp. Southeast Asia Sri Lanka Tropical rain forest Wood specific gravity

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History and possible mechanisms of prehistoric human migration to the Tibetan Plateau

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Science China Earth Sciences 2016年第9期59卷 1765-1778页

作者： ZhaNG DongJu DONG GuangHui WANG Hui rEN XiaoYan ha PiPu'u QIANG Mingrui CHEN FaHui Key Laboratory of Western China's Environmental Systems Ministry of Education College of Earth Environmental Sciences Lanzhou University Lanzhou 730000 China Gansu Provincial Institute of Cultural relics and Archaeological research Lanzhou 730000 China Qinghai Provincial Institute of Cultural relics and Archaeological research Xining 810007 China Cultural relic Conservation Institute Lhasa 850000 China

Prehistoric human history on the Tibetan Plateau is a hotly debated topic. Archaeological research on the plateau during the past few decades has enormously improved our understanding of the topic and makes it possible for us to consider the processes and mechanisms of prehistoric human migration to the region. By reviewing the published archaeological research on the Tibetan Plateau, we propose that the first people on the plateau initially spread into the He-Huang region from the Chinese Loess Plateau, and then moved to the low elevation Northeastern Tibetan Plateau and perhaps subsequently to the entire plateau. This process consisted of four stages.(1) During the climatic amelioration of the Last Deglacial period(15–11.6 ka BP), upper Paleolithic hunter-gatherers with a developed microlithic technology first spread into the Northeastern Tibetan Plateau.(2) In the early-mid Holocene(11.6–6 ka BP), Epipaleolithic microlithic hunter-gatherers were widely distributed on the northeastern plateau and spread southwards to the interior plateau, possibly with millet agriculture developed in the neighboring low elevation regions.(3) In the mid-late Holocene(6–4 ka BP), Neolithic millet farmers spread into low elevation river valleys in the northeastern and southeastern plateau areas.(4) In the late Holocene(4–2.3 ka BP), Bronze Age barley and wheat farmers further settled on the high elevation regions of the Tibetan Plateau, especially after 3.6 ka BP. Finally, we suggest that all of the reported Paleolithic sites earlier than the LGM on the Tibetan Plateau need further examination.

关键词： Tibetan Plateau Prehistoric archaeology Human migration Driving mechanisms

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“意识形态”虚名下的利益考量——美国对阿拉伯民族主义政策的缘起

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内蒙古民族大学学报（哲学社会科学版） 2024年第3期50卷 50-61页

作者：哈冠群西北政法大学政治与公共管理学院陕西西安710122

20世纪50年代,阿拉伯民族主义浪潮席卷整个中东地区。为维护自身在中东地区的核心利益,美国艾森豪威尔政府的中东政策经历重要转变。执政初期,艾森豪威尔将阿拉伯民族主义划分为“良善”与“激进”两股势力,企图改变阿拉伯民族主义内部... 详细信息

20世纪50年代,阿拉伯民族主义浪潮席卷整个中东地区。为维护自身在中东地区的核心利益,美国艾森豪威尔政府的中东政策经历重要转变。执政初期,艾森豪威尔将阿拉伯民族主义划分为“良善”与“激进”两股势力,企图改变阿拉伯民族主义内部的力量对比,削弱“激进”阿拉伯民族主义的政治倾向,然而这种“蓄意引导”的策略并未实现艾森豪威尔政府的预期目标,反而在阿拉伯世界引发大规模的民族主义浪潮。考虑到苏联在中东地区的影响力逐渐加强,美国改变对“激进”民族主义的敌对态度,并试图联合纳赛尔共同对抗活跃于中东地区的共产主义者。主导艾森豪威尔时期美国对阿拉伯民族主义政策的原因与美国对中东战略之根源类似,与意识形态即宗教、共产主义或民族主义价值观无关,其确立与调整的根基在于美国称霸世界的国家利益。

关键词：美国中东政策阿拉伯民族主义艾森豪威尔

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Aboveground carbon sequestration of Cunninghamia lanceolata forests:Magnitude and drivers

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Forest Ecosystems 2024年第1期11卷 32-41页

作者： Chen Wang Shuguang Liu Yu Zhu Andrew r.Smith Ying Ning Deming Deng National Engineering Laboratory for Applied Technology of Forestry&Ecology in South China Central South University of Forestry and TechnologyChangsha 410004China Technology Innovation Center for Ecological Conservation and restoration in Dongting Lake Basin Ministry of Natural ResourcesChangsha 410007China College of Life Science and Technology Central South University of Forestry and TechnologyChangsha 410004China School of Ecology and Environment Hainan UniversityHaikou 570228China School of Natural Sciences Bangor UniversityGwyneddLL572UWUK College of Forestry Central South University of Forestry and TechnologyChangsha 410004China Hunan Prospecting Designing&research General Institute for Agriculture Forestry&IndustryChangsha 410007China

understanding the spatial variation,temporal changes,and their underlying driving forces of carbon sequestration in various forests is of great importance for understanding the carbon cycle and carbon management *** carbon density and sequestration in various Cunninghamia lanceolata forests,extensively cultivated for timber production in subtropical China,vary with biodiversity,forest structure,environment,and cultural factors remain poorly explored,presenting a critical knowledge gap for realizing carbon sequestration supply potential through *** on a large-scale database of 449 permanent forest inventory plots,we quantified the spatial-temporal heterogeneity of aboveground carbon densities and carbon accumulation rates in Cunninghamia lanceolate forests in Hunan Province,China,and attributed the contributions of stand structure,environmental,and management factors to the heterogeneity using quantile age-sequence analysis,partial least squares path modeling(PLS-PM),and hot-spot *** results showed lower values of carbon density and sequestration on average,in comparison with other forests in the same climate zone(i.e.,subtropics),with pronounced spatial and temporal ***,quantile regression analysis using carbon accumulation rates along an age sequence showed large differences in carbon sequestration rates among underperformed and outperformed forests(0.50 and 1.80 Mg·ha^(-1)·yr^(-1)).PLS-PM demonstrated that maximum DBH and stand density were the main crucial drivers of aboveground carbon density from young to mature ***,species diversity and geotopographic factors were the significant factors causing the large discrepancy in aboveground carbon density change between low-and high-carbon-bearing *** analysis revealed the importance of culture attributes in shaping the geospatial patterns of carbon *** work highlighted that retaining largesized DBH trees and increasing shade-t

关键词： Carbon density Carbon accumulation rate Forest age Spatial variation Cultural influence

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Kavalactone yangonin induces autophagy and sensitizes bladder cancer cells to flavokawain A and docetaxel via inhibition of the mTOr pathway

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The Journal of Biomedical research 2017年第5期31卷 408-418页

作者： Zhongbo Liu u-Syn ha Ke Yu Chunli Wu Noriko Yokoyama Xiaolin Zi Departments of urology University of CaliforniaIrvine Orange CA 92868 USA. Pharmacology University of CaliforniaIrvine Orange CA 92868 USA. Chao Family Comprehensive Cancer Center University of CaliforniaIrvine Orange CA 92868 USA.

Consumption of kava(Piper methysticum Forst) has been linked to reduced cancer risk in the South Pacific *** are major bioactive components in kava root extracts, which have recently demonstrated anti-cancer activities. However, molecular mechanisms of kavalactones' anti-cancer action remain largely unknown. We have identified two kavalactones, yangonin and 5' 6'-dehydrokawain, as potent inducers of autophagic cell death in bladder cancer cells. The effect of yangonin inducing autophagy is associated with increased expression of beclin and *** addition, yangonin increases the expression of LKB1 and decreases the phosphorylation of Akt, PrAS40, rpS6,p70S6 K and 4E-BP1, leading to increased binding of 4E-BP1 to m7 GTP. The growth inhibitory effects of yangonin were attenuated in TSC1 or LKB1 knockout mouse embryonic fibroblasts, suggesting that TSC1 and LKB1 expression may contribute to optimal growth inhibition by yangonin. Furthermore, yangonin reduces the viability of bladder cancer cell lines derived from different stages of human bladder cancer, and acts synergistically with apoptosis-inducing agents such as docetaxel and flavokawain A. Our results support a novel anti-bladder cancer mechanism by yangonin and further studies are needed to assess the potential use of yangonin for bladder cancer prevention and treatment

关键词： yangonin bladder cancer autophagy mTOr

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Influence of Nitrogen Levels and Application Methods on Yield and Quality of Sorghum

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Pedosphere 2008年第2期18卷 236-241页

作者： A.rASHID r.u.KhaN H.uLLAH Arid Zone research Irstitute Department of Agronomy Faculty of Agriculture Gomal University

A field study was conducted for two years at the Arid Zone research Institute, Dera Ismail Khan, Pakistan, to determine the optimum level of nitrogen and efficient application method in the production of sorghum （Sorghum bicolor L.）. using four levels of nitrogen, i.e., 0, 60, 90, and 120 kg ha^-1, and two different application methods （soil application and foliar spray）, the experiment was laid out in a split-plot design, where the main plots were used to determine the effective method of application and the subplots were used to detect the influence of N levels on the grain yield. The average data obtained after two years of study indicated an increase in the grain yields with an increase in N levels irrespective of the method used of N application. The grain yield increased from 2.92 to 5.61 t ha^-1 in the plots that were treated with 90 kg N ha^-1 compared with the control plots. Quadratic regression analysis showed that the increase in the yield was higher at the lower levels of N compared with the succeeding higher levels. The soil application method, producing an average grain yield of 4.79 t ha^-1, was found to be superior to the foliar spray method with an average grain yield of 4.56 t ha^-1. The protein content of the grain showed a linear increase with N application, attaining the maximum at 120 kg N ha^-1 in both the methods of N application. In addition, compared with the method of soil application, higher crude protein contents were observed using the method of foliar spray at all N levels.

关键词： foliar spray grain yield N level protein content soil application

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Anti-inflammatory and Antimicrobial Effects of Anthocyanin Extracted from Black Soybean on Chronic Bacterial Prostatitis rat Model

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Chinese Journal of Integrative Medicine 2018年第8期24卷 621-626页

作者： Byung Il Yoon Woong Jin Bae Yong Sun Choi Su Jin Kim u Syn ha Sung-Hoo Hong Dong Wan Sohn Sae Woong Kim Department of urology International St Mary's HospitalThe Catholic Kwandong University of Korea Department of urology College of MedicineThe Catholic University of Korea

Objective： To investigated the anti-inflammatory and antimicrobial effects of anthocyanins extracted from black soybean on the chronic bacterial prostatitis（CBP） rat ***： The SpragueDawley rats were divided into 4 groups,including control,ciprofloxacin,anthocyanins and anthocyanins with ciprofloxacin groups（n=8 in each group）.Then,drip infusion of bacterial suspension（Escherichia coli Z17O2：K1：H^-） into Sprague-Dawley rats was conducted to induce *** 4 weeks,results of prostate tissue,urine culture,and histological analysis on the prostate were analyzed for each ***： The use of ciprofloxacin,anthocyanins,and anthocyanins with ciprofloxacin showed statistically significant decreases in bacterial growth and improvements in the reduction of prostatic inflammation compared with the control group（P〈0.05）.The anthocyanins with ciprofloxacin group showed a statistically significant decrease in bacterial growth and improvement in prostatic inflammation compared with the ciprofloxacin group（P〈0.05）.Conclusions： These results suggest that anthocyanins may have anti-inflammatory and antimicrobial effects,as well as a synergistic effect with ***,we suggest that the combination of anthocyanins and ciprofloxacin may be effective in treating CBP to obtain a higher rate of treatment success.

关键词： prostatitis anti-bacterial agents anthocyanins

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