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Efficient photon-pair generation in layer-poled lithium niobate nanophotonic waveguides

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Light(Science & Applications) 2024年第11期13卷 2847-2856页

作者： Xiaodong Shi Sakthi Sanjeev Mohanraj veerendra Dhyani Angela anna Baiju Sihao Wang Jiapeng Sun Lin Zhou anna paterova victor Leong Di Zhu A*STAR Quantum Innovation Centre(Q.InC) Institute of Materials Research and Engineering(IMRE)Agency for ScienceTechnology and Research(A*STAR)Singapore 138634Singapore Department of Physics National University of SingaporeSingapore 117542Singapore Department of Materials Science and Engineering National University of SingaporeSingapore 117575Singapore Centre for Quantum Technologies National University of SingaporeSingapore 117543Singapore

Integrated photon-pair sources are crucial for scalable photonic quantum ***-film lithium niobate is a promising platform for on-chip photon-pair generation through spontaneous parametric down-conversion(SPDC).However,the device implementation faces practical *** poled lithium niobate(PPLN),despite enabling flexible quasi-phase matching,suffers from poor fabrication reliability and device repeatability,while conventional modal phase matching(MPM)methods yield limited efficiencies due to inadequate mode ***,we introduce a layer-poled lithium niobate(LPLN)nanophotonic waveguide for efficient photon-pair *** leverages layer-wise polarity inversion through electrical poling to break spatial symmetry and significantly enhance nonlinear interactions for MPM,achieving a notable normalized second-harmonic generation(SHG)conversion efficiency of 4615%W^(−1)cm^(−2).Through a cascaded SHG and SPDC process,we demonstrate photon-pair generation with a normalized brightness of 3.1×10^(6)Hz nm^(−1)mW^(−2)in a 3.3 mm long LPLN waveguide,surpassing existing onchip sources under similar operating ***,our LPLN waveguides offer enhanced fabrication reliability and reduced sensitivity to geometric variations and temperature fluctuations compared to PPLN *** expect LPLN to become a promising solution for on-chip nonlinear wavelength conversion and non-classical light generation,with immediate applications in quantum communication,networking,and on-chip photonic quantum information processing.

关键词： waveguide waveguides lithium

Semantic Segmentation of Lumbar vertebrae Using Meijering U-Net(MU-Net)on Spine Magnetic Resonance Images

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 733-757页

作者： Lakshmi S v v Shiloah Elizabeth Darmanayagam Sunil Retmin Raj Cyril Department of Computer Science and Engineering College of Engineering GuindyAnna UniversityChennai600025India Department of Information Technology Madras Institute of TechnologyAnna UniversityChrompetChennai600044India

Lower back pain is one of the most common medical problems in the world and it is experienced by a huge percentage of people *** to its ability to produce a detailed view of the soft tissues,including the spinal cord,nerves,intervertebral discs,and vertebrae,Magnetic Resonance Imaging is thought to be the most effective method for imaging the *** semantic segmentation of vertebrae plays a major role in the diagnostic process of lumbar *** is difficult to semantically partition the vertebrae in Magnetic Resonance Images from the surrounding variety of tissues,including muscles,ligaments,and intervertebral discs.U-Net is a powerful deep-learning architecture to handle the challenges of medical image analysis tasks and achieves high segmentation *** work proposes a modified U-Net architecture namely MU-Net,consisting of the Meijering convolutional layer that incorporates the Meijering filter to perform the semantic segmentation of lumbar vertebrae L1 to L5 and sacral vertebra ***-colour mask images were generated and used as ground truth for training the *** work has been carried out on 1312 images expanded from T1-weighted mid-sagittal MRI images of 515 patients in the Lumbar Spine MRI Dataset publicly available from Mendeley *** proposed MU-Net model for the semantic segmentation of the lumbar vertebrae gives better performance with 98.79%of pixel accuracy(PA),98.66%of dice similarity coefficient(DSC),97.36%of Jaccard coefficient,and 92.55%mean Intersection over Union(mean IoU)metrics using the mentioned dataset.

关键词： Computer aided diagnosis(CAD) magnetic resonance imaging(MRI) semantic segmentation lumbar vertebrae deep learning U-Net model

Molecular targets of cancer chemoprevention by garlic-derived organosulfides

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Acta Pharmacologica Sinica 2007年第9期28卷 1355-1364页

作者： anna HERMAN-ANTOSIEWICZ anna A POWOLNY Shivendra v SINGH Department of Molecular Biology University of Gda(sk Kladki 2480-822 GdaskPoland Department of Pharmacology and University of Pittsburgh Cancer Institute University of Pittsburgh School of MedicinePittsburghPennsylvania 15213USA

The medicinal benefits of Allium vegetables,especially garlic,have been notedthroughout recorded *** known health benefits of Allium vegetablesand their constituents include cardiovascular protective effects,stimulation ofimmune function,reduction of blood glucose level,radioprotection,improvementof memory loss,protection against microbial,viral and fungal infections,as well asanticancer ***-based case control studies have suggested aninverse correlation between dietary intake of Allium vegetables and the risk ofdifferent types of *** anticarcinogenic effect of Allium vegetables in-cluding garlic is attributed to organosulfur compounds (OSC),which are highlyeffective in affording protection against cancer in animal models induced by avariety of chemical *** recent studies have shown that certainnaturally occurring OSC analogues can suppress proliferation of cancer cells inculture and in *** OSC-induced changes in the proliferation of cancer cellsare frequently associated with perturbations in cell cycle progression and induc-tion of G2/M phase *** OSC have also been demonstrated to induceapoptosis via the intrinsic pathway by altering the ratio of the Bcl-2 family ofproteins both in cell culture and in in vivo ***-angiogenic activity forgarlic-derived OSC has also been *** article summarizes currentknowledge on molecular targets of cancer chemoprevention by OSC.

关键词： garlic organosulfides apoptosis cell cycle angiogenesis chemoprevention

Reducing intrathecal pressure after traumatic spinal cord injury: a potential clinical target to promote tissue survival

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Neural Regeneration Research 2015年第3期10卷 380-382页

作者： anna v Leonard Robert vink School of Medical Sciences University of Adelaide Division of Health Sciences University of South Australia

Spinal cord injury （SCI） is an unexpected event that is both devastating and debilitating, resulting in not just motor and sensory loss, but also autonomic dysfunction of the bladder, bowel and sexual organs. Currently, there are no treatments available to improve outcome follow- ing SCI, leaving individuals with permanent and lifelong physical disability. Worldwide it is estimated that more than 500,000 people sustain a SCI each year, with average lifetime cost of paraplegia and quadriplegia estimated at $5 million and $9.5 million respectively. We therefore urgently need effective therapies to improve quality of life following SCI, and this requires a greater understanding of how cell and axonal injury develops after the traumatic event.

关键词： ITP TBI a potential clinical target to promote tissue survival Reducing intrathecal pressure after traumatic spinal cord injury SCI

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Structural traits of woody plants and geomorphological conditions to the vegetation recovery at Ksudach caldera(Southern Kamchatka) since the explosive eruption in 1907

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Journal of Mountain Science 2020年第7期17卷 1613-1635页

作者： KOPANINA anna v LEBEDEvA Ekaterina v vLASOvA Inna I TALSKIKH Anastasia v Institute of Marine Geology and Geophysics Far Eastern Branch of the Russian Academy of SciencesNauka street1 B693022Yuzhno-SakhalinskRussia Institute of Geography Russian Academy of SciencesStaromonetny s-str.29119017MoscowRussia

This study considers the restoration of the plant cover destroyed by a catastrophic volcano eruption in the south of Kamchatka Peninsula(the Ksudach caldera,Shtyubel cone),with a particular attention to the role of woody *** aims to qualitatively estimate(at a qualitative level)the rate of the primary succession development depending on the microrelief and the modern relief-forming *** vegetation recovery in the caldera after the Shtyubel cone eruption 109 years ago proceeds slowly and *** proceeds most slowly on a thick tephra mantle continuously disturbed by water and wind erosion,lahars,debris flows,landslides,*** conditions are most typical of the western part of the caldera dominated by pumice fields with occasional patches of pioneer herbs and dwarf *** tundra communities with gradually expanding patches of shrub alder develop in the southern,eastern and northeastern parts of the Ksudach *** 1997 the area of the shrub alder communities has increased by 1.9 times,while the alpine tundra–by 1.3 times *** woody plants(dwarf shrubs and prostrate shrubs)are of particular importance in the process of the vegetation recovery on pumice *** suggest that the bark thickness of woody plants is an integrated indicator,which may serve for estimating the state of ecosystem in the course of the primary succession development on juvenile *** extremely inhospitable environments cause changes in physiological processes in the plant body and in its bark in *** results show that woody plants have a"thin"bark and develop some structural-functional arrangements for keeping bark tissues at their ***,the woody plant structure and the rate of changes in plant communities are under control of the geomorphic conditions and primarily–of physicochemical features of the pyroclastic cover.

关键词： Ksudach caldera Pioneer species Woody plants Bark Pyroclastic deposits Geomorphological processes

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Interactive effects of metal pollution and ocean acidification on physiology of marine organisms

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Current Zoology 2015年第4期61卷 653-668页

作者： anna v. Ivanina Inna M. Sokolova Department of Biological Sciences University of North Carolina at Charlotte Charlotte NC 28223 USA

Changes in the global environment such as ocean acidification （OA） may interact with anthropogenic pollutants including trace metals threatening the integrity of marine ecosystems. We analyze recent studies on the interactive effects of OA and trace metals on marine organisms with a focus on the physiological basis of these interactions. Our analysis shows that the responses to elevated CO2 and metals are strongly dependent on the species, developmental stage, metal biochemistry and the degree of environmental hypercapnia, and cannot be directly predicted from the CO2-induced changes in metal solubility and speciation. The key physiological functions affected by both the OA and trace metal exposures involve acid-base regulation, pro- tein turnover and mitochondrial bioenergetics, reflecting the sensitivity of the underlying molecular and cellular pathways to CO2 and metals. Physiological interactions between elevated CO2 and metals may impact the organisms＇ capacity to maintain ac- id-base homeostasis and reduce the amount of energy available for fitness-related functions such as growth, development and re- production thereby affecting survival and performance of estuarine populations. Environmental hypercapnia may also affect the marine food webs by altering predator-prey interactions and the trophic transfer of metals in the food chain. However, our under- standing of the degree to which these effects can impact the function and integrity of marine ecosystems is limited due the scar- city of the published research and its bias towards certain taxonomic groups. Future research priorities should include studies of metal x Pco2 interactions focusing on critical physiological functions （including acid-base, protein and energy homeostasis） in a greater range of ecologically and economically important marine species, as well as including the field populations naturally ex- posed （and potentially adapted） to different levels of metals and CO2 in their environments [Curre

关键词： CO2 Trace metals Metal accumulation Acid-base homeostasis Bioenergetics Estuaries

The role of mRNA splicing in prostate cancer

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Asian Journal of Andrology 2014年第4期16卷 515-521页

作者： anna v Lapuk Stanislav v volik Yuzhuo Wang Colin C Collins vancouver Prostate CentreUniversity of British Columbia Vancouver BC Canada. Department of Experimental Therapeutics BC Cancer AgencyUniversity of British Columbia Vancouver BC Canada. Department of Urologic Sciences University of British Columbia Vancouver BC Canada.

Alternative splicing （AS） is a crucial step in gene expression. It is subject to intricate regulation, and its deregulation in cancer can lead to a wide array of neoplastic phenotypes. A large body of evidence implicates splice isoforms in most if not all hallmarks of cancer, including growth, apoptosis, invasion and metastasis, angiogenesis, and metabolism. AS has important clinical implications since it can be manipulated therapeutically to treat cancer and represents a mechanism of resistance to therapy. In prostate cancer （PCa） AS also plays a prominent role and this review will summarize the current knowledge of alternatively spliced genes with important functional consequences. We will highlight accumulating evidence on AS of the components of the two critical pathways in PCa： androgen receptor （AR） and phosphoinositide 3-kinase （PI3K）. These observations together with data on dysregulation of splice factors in PCa suggest that AR and PI3K pathways may be interconnected with previously unappreciated splicing regulatory networks. In addition, we will discuss several lines of evidence implicating splicing regulation in the development of the castration resistance.

关键词： alternative splicing prostate cancer androgen receptor PI3K pathway CRPC neuroendocrine transdifferentiation REST repressor complex

Deep Forest as a framework for a new class of machine-learning models

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National Science Review 2019年第2期6卷 186-187页

作者： Lev v.Utkin anna A.Meldo Andrei v.Konstantinov Laboratory of Neural Network Technology and Artificial Intelligence Peter the Great St. Petersburg Polytechnic University

A new deep learning framework—the socalled Deep Forest (DF), proposed by Zhi-Hua Zhou and Ji Feng [1,2]—can be regarded as one of the important events of 2017 in machine learning, although it was unjustly unnoticed by a large number of researchers. The DF combines several ensemble-based methods, including Random Forests (RFs) and Stacking, into a structure that is similar to a multi-layer neural network, but each layer in the DF

关键词： Deep Forest as a framework for a new class of machine-learning models

Crafting chirality in three dimensions via a novel fabrication technique for bound states in the continuum metasurfaces

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Light(Science & Applications) 2024年第3期13卷 390-392页

作者： Zaid Haddadin anna My Nguyen Lisa v.Poulikakos Department of Electrical&Computer Engineering University of California San DiegoLa JollaCAUSA Department of Mechanical&Aerospace Engineering University of California San DiegoLa JollaCAUSA Program of Materials Science&Engineering University of California San DiegoLa JollaCAUSA

An additional deposition step was added to a multi-step electron beam lithographic fabrication process to unlock the height dimension as an accessible parameter for resonators comprising unit cells of quasi-bound stat... 详细信息

关键词： dimensions dimension intrinsic