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Relationship between Age and Neurogenesis in Old World Monkeys

Neuroscience & Medicine 2013年第3期4卷 172-180页

作者： Tarique D. Perera Arkadiy Yaretskiy anna v. rozenboym Zeena Audi Cecilia Lipira Jean Tang Jeremy Hill Lakshmi Thirumangalakudi Daniel C. Lee Andrew J. Dwork Jeremy D. Coplan Department of Biological Sciences Kingsborough Community College Brooklyn USA Departments of Psychiatry College of Physicians and Surgeons Columbia University Medical Center and New York State Psychi- atric Institute New York USA Div.sion of Cardiothoracic Surgery SUNY Downstate Medical Center Brooklyn USA Nonhuman Primate Facility Department of Psychiatry SUNY Downstate Medical Center Brook- lyn USA

Hippocampal neurogenesis continues throughout the lifespan of adult mammals, but the rates decline dramatically with increasing age. Among the factors that hav. been shown to affect neurogenesis, aging has been shown to be one of its most potent regulators in mice. The mechanism for the decline in neurogenesis with age is thought to be related to age-dependent changes in local and systemic neuroendocrinology and neurochemistry, as well as internal changes to precursor cells that result in decreased reactiv.ty to normal stimuli. Since most of the data about neurogenesis and age were established from rodent studies, we sought to study this relationship in nonhuman primates in fiv. prev.ously studied cohorts of bonnet monkeys (Macaca radiata). In the present study, we statistically analyze the relationship of age and hippocampal neurogenesis rates, as measured by the number of DCX expressing cells in the subgranular zone of the dentate gyrus in 71 subjects with ages ranging from 3.5 to 17 years. We observ.d a non-significant relationship between age and doublecortin for subjects less than nine years old (corresponding to young and full adulthood) but a linear significant decline for subjects 9 years or greater (middle age and senescence). In contrast to prev.ous studies that show neurogenesis to decline linearly throughout the lifespan, this study shows that neurogenesis occurs steadily throughout adulthood and begins to decline in middle age in bonnet macaques.

关键词： Neurogenesis Age Macaca Radiate Nonhuman Primates

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Semantic Segmentation of Lumbar v.rtebrae 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 v.ew of the soft tissues,including the spinal cord,nerv.s,interv.rtebral discs,and v.rtebrae,Magnetic Resonance Imaging is thought to be the most effectiv. method for imaging the *** semantic segmentation of v.rtebrae plays a major role in the diagnostic process of lumbar *** is difficult to semantically partition the v.rtebrae in Magnetic Resonance Images from the surrounding v.riety of tissues,including muscles,ligaments,and interv.rtebral discs.U-Net is a powerful deep-learning architecture to handle the challenges of medical image analysis tasks and achiev.s high segmentation *** work proposes a modified U-Net architecture namely MU-Net,consisting of the Meijering conv.lutional layer that incorporates the Meijering filter to perform the semantic segmentation of lumbar v.rtebrae L1 to L5 and sacral v.rtebra ***-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 av.ilable from Mendeley *** proposed MU-Net model for the semantic segmentation of the lumbar v.rtebrae giv.s 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 ov.r Union(mean IoU)metrics using the mentioned dataset.

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

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Interactiv. 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. Iv.nina Inna M. Sokolov. Department of Biological Sciences University of North Carolina at Charlotte Charlotte NC 28223 USA

Changes in the global env.ronment 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 interactiv. 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 elev.ted CO2 and metals are strongly dependent on the species, dev.lopmental stage, metal biochemistry and the degree of env.ronmental 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 inv.lv. acid-base regulation, pro- tein turnov.r and mitochondrial bioenergetics, reflecting the sensitiv.ty of the underlying molecular and cellular pathways to CO2 and metals. Physiological interactions between elev.ted CO2 and metals may impact the organisms＇ capacity to maintain ac- id-base homeostasis and reduce the amount of energy av.ilable for fitness-related functions such as growth, dev.lopment and re- production thereby affecting surv.v.l and performance of estuarine populations. Env.ronmental hypercapnia may also affect the marine food webs by altering predator-prey interactions and the trophic transfer of metals in the food chain. Howev.r, 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 lev.ls of metals and CO2 in their env.ronments [Curre

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

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Nonlinear interference in crystal superlattices

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Light(Science & Applications) 2020年第1期9卷 1239-1245页

作者： anna v.Paterov. Leonid A.Kriv.tsky Institute of Materials Research and Engineering(IMRE) Agency for Science Technology and Research(A*STAR)138634 SingaporeSingapore

Nonlinear interferometers with correlated photons hold promise to adv.nce optical characterization and metrology techniques by improv.ng their performance and *** interferometers offer subshot noise phase sensitiv.ty and enable measurements in detection-challenging regions using inexpensiv. and efficient *** sensitiv.ty of nonlinear interferometers,defined by the ability to measure small shifts of interference fringes,can be significantly enhanced by using multiple nonlinear elements,or crystal ***,to date,experiments with more than two nonlinear elements hav. not been realized,thus hindering the potential of nonlinear ***,we build a nonlinear interferometer with up to fiv. nonlinear elements,referred to as superlattices,in a highly stable and v.rsatile *** study the modification of the interference pattern for different configurations of the superlattices and perform a proof-of-concept gas sensing experiment with enhanced *** approach offers a v.able path towards broader adoption of nonlinear interferometers with correlated photons for imaging,interferometry,and spectroscopy.

关键词： spectroscopy nonlinear Nonlinear

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Modeling corrosion behav.or of gas tungsten arc welded titanium alloy

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中国有色金属学会会刊：英文版 2007年第4期17卷 676-680页

作者： M. Balasubramanian v. Jay abalan v. Balasubramanian Department of Mechanical Engineering Maamallan Institute of Technology Anna University Department of Manufacturing Engineering Anna University Department of Manufacturing Engineering Annamalai University

The pitting corrosion characteristics of pulse TIG welded Ti-6Al-4v.titanium alloy in marine env.ronment were explained. Besides the rapid adv.nce of titanium metallurgy, this is also due to the successful solution of problems associated with the dev.lopment of titanium alloy welding. The preferred welding process of titanium alloy is frequently gas tungsten arc(GTA) welding due to its comparativ.ly easier applicability and better economy. In the case of single pass GTA welding of thinner section of this alloy, the pulsed current has been found beneficial due to its adv.ntages ov.r the conv.ntional continuous current process. The benefit of the process is utilized to obtain better quality titanium weldments. Four factors, fiv. lev.ls, central composite, rotatable design matrix are used to optimize the required number of experiments. The mathematical models hav. been dev.loped by response surface method(RSM). The results rev.al that the titanium alloy can form a protectiv. scale in marine env.ronment and is resistant to pitting corrosion. Experimental results are prov.ded to illustrate the proposed approach.

关键词：钛合金脉冲电流钨电极惰性气体保护焊腐蚀行为

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Indentation fracture toughness of single-crystal Bi2Te3 topological insulators

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Nano Research 2016年第4期9卷 1032-1042页

作者： Caterina Lamuta anna Cupolillo Antonio Politano Ziya S. Aliev.Mahammad B. Babanly Ev.ueni v. Chulkov.Leonardo Pagnotta Department of Mechanical Energy and Management Engineering University ofCalabria Ponte P Bucci Cuba 44C 87036 Rende Italy Department of Physics University of Calabria Ponte P Bucci Cuba 31 C 87036 Rende Italy Institute of Catalysis and Inorganic Chemistry ANAS AZ1143 Baku Azerbaijian Institute of Physics ANAS AZ1143 Baku Azerbaijian Donostia International Physics Center (DIPC) Paseo de Manuel Lardizabal 4 20018 San Sebastian/Donostia Spain Departamento de Fisica de Materiales Universidad del Pals Vasco Apartado 1072 20080 San Sebastidn/Donostia Spain Centro de Fisica de Materiales CFM-Materials Physics Center MPC Centro Mixto CSIC-UPV/EHU Paseo de Manuel Lardizabal 5 20018 San Sebastion/Donostia Spain Saint Petersburg State Univ.rsity 198504 Saint Petersburg Russian Federation Tomsk State Univ.rsity 634050 Tomsk Russian Federation

Bismuth teUuride （Bi2Te3） is one of the most important commercial thermoelectric materials. In recent years, the discov.ry of topologically protected surface states in Bi chalcogenides has pav.d the way for their application in nanoelectronics. Determination of the fracture toughness plays a crucial role for the potential application of topological insulators in flexible electronics and nanoelectro- mechanical dev.ces. Using depth-sensing nanoindentation tests, we inv.stigated for the first time the fracture toughness of bulk single crystals of Bi2Te3 topological insulators, grown using the Bridgmantockbarger method. Our results highlight one of the possible pitfalls of the technology based on topological insulators.

关键词： topological insulators bismuth telluride (Bi2Te3) fracture toughness nanoindentation

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Structural traits of woody plants and geomorphological conditions to the v.getation recov.ry at Ksudach caldera(Southern Kamchatka) since the explosiv. 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.LEBEDEv. Ekaterina v.v.ASOv. 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 cov.r destroyed by a catastrophic v.lcano eruption in the south of Kamchatka Peninsula(the Ksudach caldera,Shtyubel cone),with a particular attention to the role of woody *** aims to qualitativ.ly estimate(at a qualitativ. lev.l)the rate of the primary succession dev.lopment depending on the microrelief and the modern relief-forming *** v.getation recov.ry 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 dev.lop 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 v.getation recov.ry on pumice *** suggest that the bark thickness of woody plants is an integrated indicator,which may serv. for estimating the state of ecosystem in the course of the primary succession dev.lopment on juv.nile *** extremely inhospitable env.ronments cause changes in physiological processes in the plant body and in its bark in *** results show that woody plants hav. a"thin"bark and dev.lop 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 cov.r.

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

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Giga- and terahertz-range nanoemitter based on peapod structure

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Nano Research 2015年第8期8卷 2595-2602页

作者： Michail M. Slepchenkov.anna S. Kolesnikov. George v. Sav.styanov. Igor S. Nefedov.Ilya v. Anoshkin Albert G. Nasibulin Olga E. Glukhov. Department of Physics Saratov State University Saratov 410012 Russia Department of Radio Science and Engineering Aalto University Aalto P.O. Box 13000 Finland kolkov. Institute of Science and Technology Skolkovo 143025 Russia

We propose a theoretical model of a nanoemitter for giga- and terahertz-range wav.s. The model is based on a peapod structure comprising a carbon nanotube with chiral indices （10, 10）. Three encapsulated and partially polymerized fuUerene C60 molecules and a positiv.ly charged C60 fullerene are trapped inside the nanotube. The motion of the charged fullerene and the radiation frequency were controlled using an external electric field. Stable terahertz radiation at a frequency of 0.36 THz was produced at 300 K with an external electrical field of 10 v.μm. Stable radiation in the gigahertz range was observ.d at 50 K with an electric field below 10 v.m. A theoretical simulation was performed using the tight-binding molecular dynamics method with a description of the v.n der Waals interaction by the Morse potential. The system described by the theoretical model was experimentally observ.d.

关键词： fullerenes nanotubes electronics simulations molecular modeling

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Nitrogen Release from Slow-Release Fertilizers in Soils with Different Microbial Activ.ties

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Pedosphere 2018年第2期28卷 332-340页

作者： Pierfrancesco NARDI Ulderico NERI Giov.nni DI MATTEO Alessandra TRINCHERA Rosario NAPOLI Roberta FARINA Guntur v. SUBBARAO anna BENEDETTI CREA-Council for Agricultural Research and Economics Research Center for Agriculture and Environment Via della Navicella 2Rome 00184 (Italy) Japan International Research Center for Agricultural Sciences (JIRCAS) Tsukuba 305-8686 (Japan)

Soil microbial activ.ty is recognized as an important factor affecting nitrogen (N) release from slow-release fertilizers. Howev.r,studies on the effect of size and activ.ty of soil microflora on fertilizer degradation hav. prov.ded contrasting results. To date, no clear relationships exist between soil microbial activ.ty and the release of N from slow-release fertilizers. Hence, the aim of this study was to better understand such relationships by determining the release of N from three slow-release fertilizers in soils with different microbial activ.ties. Soils were amended with urea-formaldehyde (UF), isobutylidene diurea (IBDU), and crotonylidene diurea (CDU). Urea, a soluble fertilizer, was used as the control. Fertilized soil samples were placed in a leaching system, and the release of N was determined by measuring ammonium-N and nitrate-N concentrations in leachates during 90 d of incubation. Non-linear regression was used to fit N leaching rate to a first-order model. In all the treated soils, N was released in the order: urea (89%–100%) > IBDU (59%–94%) >UF (46%–73%) > CDU (44%–56%). At the end of incubation, N released from CDU did not differ (P > 0.05) among soils. On the contrary, UF and IBDU released significantly lower (P v.ty and lower *** rate constant (K_0) for UF was lower (P v.ty had a marginal effect on fertilizer mineralization.

关键词： ammonium-N crotonylidene diurea isobutylidene diurea nitrate-N non-linear regression urea-formaldehyde

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Cytotoxicity and non-specific cellular uptake of bare and surface-modified upconv.rsion nanoparticles in human skin cells

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Nano Research 2015年第5期8卷 1546-1562页

作者： anna E. Guller Alia N. Generalov. Elena v. Petersen Andrey v. Nechaev.Inna A. Trusov. Nikolay N. Landyshev.Annemarie Nadort Ekaterina A. Grebenik Sergey M. Deyev.Anatoly B. Shekhter Andrei v. Zv.agin Macquarie Univ.rsity Australia I.M. Sechenov.First Moscow State Medical Univ.rsity Russia Shemyakin-Ov.hinnikov.Institute of Bioorganic Chemistry Russian Academy of Sciences Russia Nizhny Nov.orod State Univ.rsity Russia Moscow Institute of Physics and Technology Russia Moscow State Univ.rsity of Fine Chemical Technologies Russia Univ.rsity of Amsterdam the Netherlands

The cytotoxicity and non-specific cellular uptake of the most popular composition of upconv.rsion nanoparticle （UCNP）, NaYF4：Yb^3＋：Er^3＋, is reported using normal human skin cells, including dermal fibroblasts and immortalized human epidermal linear keratinocytes （HaCaT）. A new hydrophilization reaction of as-synthesized UCNPs based on tetramethylammonium hydroxide （TMAH） enabled ev.luation of the intrinsic cytotoxicity of bare UCNPs. The cytotoxicity effects of the UCNP surface-coating and polystyrene host were inv.stigated ov.r the concentration range 62.5-125 μg/mL with 24-h incubation, using a MTT test and optical microscopy. The fibroblast v.ability was not compromised by UCNPs, whereas the v.ability of keratinocytes v.ried from 52% ± 4% to 100% ± 10% than the control group, depending on the surface modification. Bare UCNPs reduced the keratinocyte v.ability to 76% ± 3%, while exhibiting profound non-specific cellular uptake. Hydrophilic poly（D,L-lactide）- and poly（maleic anhydride-alt-l-octadecene）-coated UCNPs were found to be least cytotoxic among the polymer-coated UCNPs, and were readily internalized by human skin cells. Polystyrene microbeads impregnated with UCNPs remained nontoxic. Surprisingly, no correlation was found between UCNP cytotoxicity and the internalization lev.l in cells, although the latter ranged broadly from 0.03% to 59%, benchmarked against 100% uptake lev.l of TMAH-UCNPs.

关键词： nanoparticle upconv.rsion surface modification biocompatibility cytotoxicity human skin

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