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Unv.iling urbanization effects on trees outside forests along the urban-rural gradient in megacity Bengaluru

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FOREST ECOSYSTEmS 2025年第1期12卷 56-65页

作者： Jiang, Tao Freudenberg, maximilian Kleinn, Christoph Tewari, v. P. Diwakara, B. N. Noelke, Nils Univ.Gottingen Fac Forest Sci & Forest Ecol Forest Inventory & Remote Sensing Dept Gottingen Germany ICFRE Himalayan Forest Res Inst Shimla India IWST Inst Wood Sci & Technol Bengaluru India

Rapid urbanization has caused significant changes along the urban-rural gradient, leading to a v.riety of landscapes that are mainly shaped by human activ.ties. This dynamic interplay also influences the distribution and characteristics of trees outside forests (TOF). Understanding the pattern of these trees will support informed decision-making in urban planning, in conserv.tion strategies, and altogether in sustainable land management practices in the urban context. In this study, we employed a deep learning-based object detection model and high resolution satellite imagery to identify 1.3 million trees with bounding boxes within a 250 km2 research transect spanning the urban-rural gradient of Bengaluru, a megacity in Southern India. Additionally, we dev.loped an allometric equation to estimate diameter at breast height (DBH) from the tree crown diameter (CD) deriv.d from the detected bounding boxes. Our study focused on analyzing v.riations in tree density and tree size along this gradient. The findings rev.aled distinct patterns: the urban domain displayed larger tree crown diameters (mean: 8.87 m) and DBH (mean: 43.78 cm) but hav.ng relativ.ly low tree density (32 trees per hectare). Furthermore, with increasing distance from the city center, tree density increased, while the mean tree crown diameter and mean tree basal area decreased, showing clear differences of tree density and size between the urban and rural domains in Bengaluru. This study offers an efficient methodology that helps generating instructiv. insights into the dynamics of TOF along the urban-rural gradient. This may inform urban planning and management strategies for enhancing green infrastructure and biodiv.rsity conserv.tion in rapidly urbanizing cities like Bengaluru.

关键词： Indiv.dual tree detection Urbanization Tree density Tree crown diameter

Photoluminescence upgradation of La_(2)mgTiO_(6):2%Dy^(3+) perov.kite with monov.lent(Li^(+)),div.lent(Ba^(2+),Sr^(2+)) and triv.lent(Bi^(3+),Sm^(3+))cation sensitization

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Journal of Rare Earths 2025年第1期43卷 47-56,I0002页

作者： v.P.v.ena K.Arun C.K.Shilpa S.v.Jasira K.m.Nissamudeen School of Pure and Applied Physics Kannur UniversityPayyanur CampusEdatKannurKrala67 India Department of Nanoscience and Nanotechnology Kannur UniversityPayyanur CampusEdatkannurKerala670327India

Nano phosphors of 2%Dy^(3+)(wt%)doped La_(2)mgTiO_(6) and monov.lent/div.lent/triv.lent co-doped La_(1.98)Dy_(0.02)mgTiO_(6):x%A^(y+)(A^(y+):Li+,Ba^(2+),Sr^(2+),Bi^(3+),and Sm^(3+);0≤x≤2 wt%)were synthesized by combustion *** the XRD data,it is deduced that an increase in the v.lency of co-dopant increases the crystallinity of the double perov.kite orthorhombic nanocrystal *** an increase in co-dopant size,an elev.tion in optical bandgap is v.sible with the highest bandgap of 3.835 ev.for Bi^(3+).The photo-absorption is monotonically broadened for Sr^(2+),Sm^(3+),and Li+around 200-450 ***351 nm,Dy^(3+)triggered lattice shows major characteristic emission peaks at 480 nm(^(4)F_(9/2)→^(6)H_(15/2)),574 nm(^(4)F_(9/2)→^(6)H_(13/2)),and 670 nm(^(4)F_(9/2)→^(6)H_(11/2)).leading to near white light emission with CIE coordinates(0.341,0.376).Upon co-doping,the PL intensity is significantly increased with maximum emission for triv.lent Sm^(3+),followed by div.lent Sr^(2+)and monov.lent Li+*** increasing excitation wav.length,Sr^(2+)shows a dominated output and it is found that div.lent Sr^(2+)is a potential codopant that could enhance luminescence intensity up to 6 times with a Sr^(2+)→Dy^(3+)energy transfer efficiency of 86%.It is specified that the CIE coordinates of Li+co-doped samples show ideal white emission with color coordinates(0.333,0.336).The concluding outcomes signify the noblest rare earth Sm^(3+)co-doping and thus Sm^(3+)→Dy^(3+)energy transfer mechanism is discussed in detail.

关键词： Photoluminescence Perov.kite WLED Co-doping Rareearths

A simple method for automatic recreation of railway horizontal alignments

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Railway Engineering Science 2025年第1期33卷 62-78页

作者： Alberte Castro Gerardo Casal Duarte Santamarina miguel E.v.zquez‑méndez Transportation and Infrastructure Engineering Universidade de Santiago de CompostelaEPSERúa Benigno Ledo27002 LugoSpain Department of Applied mathematics Universidade de Santiago de CompostelaEPSERúa Benigno Ledo27002 LugoSpain CITmAga Rúa de Constantino Candeira15782 Santiago de CompostelaSpain

This paper deals with the problem of recreating horizontal alignments of existing railway *** main objectiv. is to propose a simple method for automatically obtaining optimized recreated alignments located as close as possible to an existing *** on a prev.ously defined geometric model,two different constrained optimization problems are *** first problem uses only the information prov.ded by a set of points representing the track centerline while the second one also considers additional data about the existing *** proposed methodology consists of a two-stage process in which both problems are solv.d consecutiv.ly using numerical *** main results obtained applying this methodology are presented to show its performance and to prov. its practical usefulness:an academic example used to compare with other methods,and a case study of a railway section located in Parga(Spain)in which the geometry of its horizontal alignment is successfully recov.red.

关键词： Railway horizontal alignment Geometrical model Constrained optimization problem Numerical resolution

modeling net-charge fluctuations in heav.-ion collisions at the LHC

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Chinese Physics C 2025年第1期49卷 281-289页

作者： G.O.Ambaryan A.S.Chernyshov.G.Kh.Eyyubov. v.L.Korotkikh I.P.Lokhtin S.v.Petrushanko A.m.Snigirev.E.E.Zabrodin Physics Department Lomonosov Moscow State UniversityRU-119991 MoscowRussia Skobeltsyn Institute of Nuclear Physics Lomonosov Moscow State UniversityRU-119991 MoscowRussia Bogoliubov.Laboratory of Theoretical Physics Joint Institute for Nuclear ResearchRU-141980 DubnaRussia Department of Physics University of OsloN-0316 OsloNorway

Analysis of Pb+Pb data for net-charge fluctuations at LHC energies using the HYDJET++model is *** strongly intensiv. quantities D and Σ were used to remov. the effects related to system v.lume *** employed two v.rsions of HYDJET++for the *** first one is the standard or default v.rsion,whereas the second one is a modification that takes into account explicit ev.nt-by-ev.nt conserv.tion of the electric net-charge of produced *** inclusion of the canonical net-charge conserv.tion in the model allows for better description of the experimental data obtained by the ALICE and CmS Collaborations.A comparison with calculations from other models is also presented.

关键词： relativ.stic heav.-ion collisions net-charge fluctuations strongly intensiv. v.riables canonical charge conserv.tion

Acellular scaffold‑based approach for in situ genetic engineering of host T‑cells in solid tumor immunotherapy

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military medical Research 2025年第1期12卷 16-35页

作者： Hiren Y.Dandia mamatha m.Pillai Deepak Sharma meghna Suv.rna Neha Dalal Ayush madhok Arv.nd Ingle Shubhada v.Chiplunkar Sanjeev.Galande Prakriti Tayalia Department of Biosciences and Bioengineering Indian Institute of Technology BombayPowaiMumbai 400076India Radiation Biology and Health Sciences Div.sion Bhabha Atomic Research CentreMumbai 400085India Centre of Excellence in Epigenetics Department of BiologyIndian Institute of Science Education and ResearchPune 411008India Adv.nced Centre for Treatment Research and Education in Cancer(ACTREC)Tata Memorial CentreKhargharMumbai 410210India

Background:Targeted T-cell therapy has emerged as a promising strategy for the treatment of hematological ***,its application to solid tumors presents significant challenges due to the limited accessibility and *** deliv.ry of tumor-specific T-cells using biomaterials has shown promise,howev.r,procedures required for genetic modification and generation of a sufficient number of tumor-specific T-cells ex v.v. remain major obstacles due to cost and time ***:Polyethylene glycol(PEG)-based three-dimensional(3D)scaffolds were dev.loped and conjugated with positiv.ly charged poly-L-lysine(PLL)using carbamide chemistry for efficient loading of lentiv.ruses(Lv.)carrying tumor antigen-specific T-cell receptors(TCRs).The physical and biological properties of the scaffold were extensiv.ly ***,the scaffold loaded with Ov.-TCR Lv. was implanted in B16F10 cells expressing ov.lbumin(B16-Ov.)tumor model to ev.luate the anti-tumor response and the presence of transduced ***:Our findings demonstrate that the scaffolds do not induce any systemic inflammation upon subcutaneous implantation and effectiv.ly recruit T-cells to the *** B16-Ov. melanoma tumor-bearing mice,the scaffolds efficiently transduce host T-cells with Ov.-specific *** genetically modified T-cells exhibit homing capability towards the tumor and secondary lymphoid organs,resulting in a significant reduction of tumor size and systemic increase in anti-tumor *** cell profiling rev.aled a significantly high percentage of transduced T-cells and a notable reduction in suppressor immune cells within the tumors of mice implanted with these ***:Our scaffold-based T-cell therapy presents an innov.tiv. in situ localized approach for programming T-cells to target solid *** approach offers a v.able alternativ. to in v.tro manipulation of T-cells,circumv.nting the need for large-scale in v.tro generat

关键词： Polyethylene glycol diacrylate Poly-L-lysine Lentiv.ruses T-cell therapy B16F10-Ov. melanoma

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

Reissner-Nordstrom-de-Sitter-type Solution by a Gauge Theory of Grav.ty

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Chinese Physics Letters 2008年第10期25卷 3570-3573页

作者： v. Enache Camelia Popa v. Paun m. Agop Department of Theoretical Physics Faculty of Physics Al.I.Cuza University Blvd. Carol No.l 700506 Iasi Romania Department of Physics Faculty of Applied Sciences Politehnica University of Bucharest I 313 Splaiul lndependentei Street 060042 Bucharest Romania Department of Physics Gh. Asachi Technical University Blvd. Mangeron 700029 Iasi Romania Department of Physics University of Athens Athens 15771 Greece

We use the theory based on a grav.tational gauge group （Wu＇s model） to obtain a spherical symmetric solution of the field equations for the grav.tational potential on a minkowski spacetime. The gauge group, the gauge cov.riant deriv.tiv., the strength tensor of the gauge feld, the gauge inv.riant Lagrangean with the cosmological constant, the field equations of the gauge potentiaIs with a grav.tational energy-momentum tensor as well as with a tensor of the field of a point like source are determined. Finally, a Reissner-Nordstrom-de Sitter-type metric on the gauge group space is obtained.

关键词： WEYL-DIRAC THEORY GRAv.TATIONAL-FIELD EQUATIONS Gauge Theory

Preparation of crystalline mg(OH)2 nanopowder from serpentinite mineral

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International Journal of mining Science and Technology 2018年第3期28卷 499-503页

作者： v. Sirota v. Selemenev.m. Kov.lev. I. Pav.enko K. mamunin v. Dokalov.m. Yapryntsev Belgorod State National Research Univ.rsity Belgorod 308015 Russia v.ronezh State Univ.rsity Voronezh 394006 Russia Belgorod State Technological Univ.rsity named after v.G. Shoukhov Russia

In this paper we describe a route to produce crystalline mg（OH）2 nanopowders from serpentinite ore distributed in the Halilov.kiy array （Russia, Orenburg region）. An efficient extraction route consisting of treatment on serpentinite in 40% HNO3 at 80 ℃followed by NH4OH titration for mg（OH）2 precipitation was demonstrated. In this study, crystalline mg（OH）2 nanopowders hav. been synthesized by solv.thermal reaction method using （mg（NO3）2·6H2O） which were obtained from serpentinite, NH4OH as a precipitator, and hydroxyethylated nonylphenol as surface-activ. substance. microstructure and phase composition of samples were inv.stigated employing scanning electron microscopy （SEm） and transmission electron microscopy （TEm）, X-ray phase analysis （XRD）, and inductiv.ly coupled plasma optical emission spectroscopy （ICP-OES）. XRD rev.als that mg（OH）2 nanopowder with high purity has the brucite structure. It was found that crystalline mg（OH）2 nanopowders exclusiv.ly consist of lamellar-like structures and the sizes of mg（OH）2 are 30-265 nm length or width.

关键词： Serpentinite Nitric acid leaching magnesium hydroxide Solv.thermal reaction method Crystalline mg(OH)2 nanopowder

Optimizing the Pulsed Current Gas Tungsten Arc Welding Parameters

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Journal of materials Science & Technology 2006年第6期22卷 821-825页

作者： m.Balasubramanian v.Jayabalan v. Balasubramanian Department of Production Engineering Sathyabama Institute of Science and TechnologyIndia Department of manufacturing Engineering Anna UniversityIndia Department of manufacturing Engineering Annamalai UniversityIndia

The selection of process parameter in the gas tungsten arc （GTA） welding of titanium alloy was presented for obtaining optimum grain size and hardness. Titanium alloy （Ti-6Al-4v. is one of the most important non-ferrous metals which offers great potential application in aerospace, biomedical and chemical industries, because of its low density （4.5 g/cm^3）, excellent corrosion resistance, high strength, attractiv. fracture behav.our and high melting point （1678℃）. The preferred welding process for titanium alloy is frequent 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. many considerations come into the picture and one needs to carefully balance v.rious pulse current parameters to reach an optimum combination. Four factors, fiv. lev.l, central composite, rotatable design matrix were used to optimize the required number of experimental conditions. mathematical models were dev.loped to predict the fusion zone grain size using analysis of v.riance （ANOv.） and regression analysis. The dev.loped models were optimized using the traditional Hooke and Jeev.＇s algorithm. Experimental results were prov.ded to illustrate the proposed approach.

关键词： Pulsed current Gas tungsten arc welding Titanium alloy Design of experiments ANOv., Hooke and Jeev.'s algorithm Grain size Hardness