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Unveiling urbanization effects on trees outside forests along the urban-rural gradient in megacity Bengaluru

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Forest Ecosystems 2025年第01期 56-65页

作者： Tao Jiang Maximilian Freudenberg Christoph Kleinn v.P.Tewari B.n.Diwakara nils n?lke Forest Inventory and Remote Sensing Department Faculty of Forest Sciences and Forest Ecology University of G?ttingen Himalayan Forest Research Institute ICFRE Institute of Wood Science and Technology IWST

Rapid urbanization has caused significant changes along the urban-rural gradient, leading to a variety of landscapes that are mainly shaped by human activities. 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 conservation 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 km2research transect spanning the urban-rural gradient of Bengaluru, a megacity in Southern India. Additionally, we developed an allometric equation to estimate diameter at breast height(DBH) from the tree crown diameter(CD) derived from the detected bounding boxes. Our study focused on analyzing variations in tree density and tree size along this gradient. The findings revealed distinct patterns: the urban domain displayed larger tree crown diameters(mean:8.87 m) and DBH(mean: 43.78 cm) but having relatively 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 instructive insights into the dynamics of TOF along the urban-rural gradient. This may inform urban planning and management strategies for enhancing green infrastructure and biodiversity conservation in rapidly urbanizing cities like Bengaluru.

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Dendritic spine degeneration:a primary mechanism in the aging process

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neural Regeneration Research 2025年第6期20卷 1696-1698页

作者： Gonzalo Flores Leonardo Aguilar-Hernández Fernado García-Dolores Humberto nicolini Andrea Judith vázquez-Hernández Hiram Tendilla-Beltrán Instituto de Fisiología Benemérita Universidad Autónoma de Puebla(BUAP)PueblaMexico Instituto de Ciencias Forenses(InCIFO) Tribunal Superior de Justicia de la Ciudad de México(TSJCDMX).Mexico CityMexico Instituto nacional de Medicina Genómica(InMEGEn) Mexico CityMexico

Recent reports suggest that aging is not solely a physiological process in living beings;instead, it should be considered a pathological process or disease(Amorim et al., 2022). Consequently, this process involves a wide range of factors, spanning from genetic to environmental factors, and even includes the gut microbiome(GM)(Mayer et al., 2022). All these processes coincide at some point in the inflammatory process, oxidative stress, and apoptosis, at different degrees in various organs and systems that constitute a living organism(Mayer et al., 2022;AguilarHernández et al., 2023).

关键词： aging process stress

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块系岩体准共振诱发弱夹层拉压损伤断裂研究

岩石力学与工程学报 2025年第1期44卷 114-127页

作者：王凯兴徐伟刚潘一山薛佳琪 OPARIn v n KIRYAEvA T A 辽宁工程技术大学力学与工程学院俄罗斯科学院西伯利亚分院矿业研究所

当外界扰动频率接近块系岩体的固有频率时，会出现准共振现象。这一现象导致岩块间的弱夹层应变急剧变化，从而加快弱夹层的动态损伤断裂。为了研究块系岩体准共振导致岩块间弱夹层的动态拉压损伤断裂规律，基于块系岩体模型，分析准共... 详细信息

当外界扰动频率接近块系岩体的固有频率时，会出现准共振现象。这一现象导致岩块间的弱夹层应变急剧变化，从而加快弱夹层的动态损伤断裂。为了研究块系岩体准共振导致岩块间弱夹层的动态拉压损伤断裂规律，基于块系岩体模型，分析准共振状态下弱夹层的变形特征。结合岩石动态损伤断裂准则，对准共振状态下弱夹层的动态损伤断裂进行理论计算分析，进而研究动态破坏规律。通过数值模拟揭示了准共振状态下块系岩体中弱夹层的损伤演化特征。结果表明：当块系岩体发生准共振现象时，岩块间的相对位移急剧增加，使得弱夹层的应变和损伤程度明显增大；弱夹层的损伤程度在准共振频率下最高，同时受外部扰动力和弱夹层的刚度、黏性、厚度及岩块质量等系统参数的影响；块系岩体发生准共振时断裂应力增大，但从断裂到完全破坏的时间明显缩短，即残余承载能力大幅下降。该研究对认识块系岩体的动态断裂具有一定的参考价值。

关键词：岩石力学块系岩体准共振弱夹层变形动态损伤断裂

Impacts of PI3K/protein kinase B pathway activation in reactive astrocytes: from detrimental effects to protective functions

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neural Regeneration Research 2025年第4期20卷 1031-1041页

作者： Ramón Pérez-núñez María Fernanda González Ana María Avalos Lisette Leyton Cellular Communication Laboratory Programa de Biología Celular y MolecularCenter for Studies on ExerciseMetabolism and Cancer(CEMC)Instituto de Ciencias Biomédicas(ICBM)Facultad de MedicinaUniversidad de ChileSantiagoChile Advanced Center for Chronic Diseases(ACCDiS) Faculty of Chemical and Pharmaceutical Sciences&Faculty of MedicineUniversidad de ChileSantiagoChile Instituto de Ciencias Biomédicas Facultad de Ciencias de la SaludUniversidad Autónoma de ChileSantiagoChile

Astrocytes are the most abundant type of glial cell in the central nervous *** injury and inflammation,astrocytes become reactive and undergo morphological and functional *** on their phenotypic classification as A1 or A2,reactive astrocytes contribute to both neurotoxic and neuroprotective responses,***,this binary classification does not fully capture the diversity of astrocyte responses observed across different diseases and *** analysis has revealed that reactive astrocytes have a complex landscape of gene expression profiles,which emphasizes the heterogeneous nature of their *** actively participate in regulating central nervous system inflammation by interacting with microglia and other cell types,releasing cytokines,and influencing the immune *** phosphoinositide 3-kinase(PI3K)/protein kinase B(AKT)signaling pathway is a central player in astrocyte reactivity and impacts various aspects of astrocyte behavior,as evidenced by in silico,in vitro,and in vivo *** astrocytes,inflammatory cues trigger a cascade of molecular events,where nuclear factor-κB serves as a central mediator of the pro-inflammatory ***,we review the heterogeneity of reactive astrocytes and the molecular mechanisms underlying their *** highlight the involvement of various signaling pathways that regulate astrocyte reactivity,including the PI3K/AKT/mammalian target of rapamycin(mTOR),αvβ3 integrin/PI3K/AKT/connexin 43,and notch/PI3K/AKT *** targeting the inactivation of the PI3K/AKT cellular signaling pathway to control reactive astrocytes and prevent central nervous system damage,evidence suggests that activating this pathway could also yield beneficial *** dual function of the PI3K/AKT pathway underscores its complexity in astrocyte reactivity and brain function *** review emphasizes the importance of employing astrocyte-exclusive models to underst

关键词： inflammation integrins neuroprotective neurotoxic phosphatidylinositol 3-kinase reactive astrocytes signal transduction Thy-1(CD90)

Brain-derived neurotrophic factor signaling in the neuromuscular junction during developmental axonal competition and synapse elimination

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neural Regeneration Research 2025年第2期20卷 394-401页

作者： Josep Tomàs víctor Cilleros-Mañé Laia Just-Borràs Marta Balanyà-Segura Aleksandra Polishchuk Laura nadal Marta Tomàs Carolina Silvera-Simón Manel M.Santafé Maria A.Lanuza Unitat d’Histologia i neurobiologia(UHneurob) Facultat de Medicina i Ciències de la SalutUniversitat Rovira i VirgiliReusSpain

During the development of the nervous system,there is an overproduction of neurons and *** competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or *** have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal development and synapse elimination process versus the synapse *** purpose of this review is to describe the neurotrophic influence on developmental synapse elimination,in relation to other molecular pathways that we and others have found to regulate this *** particular,we summarize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium channels,at different nerve endings in developmental *** dynamic changes that occur simultaneously in several nerve terminals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the mechanisms of specific *** describe an activity-dependent balance(related to the extent of transmitter release)between the presynaptic muscarinic subtypes and the neurotrophin-mediated TrkB/p75nTR pathways that can influence the timing and fate of the competitive interactions between the different axon *** downstream displacement of the PKA/PKC activity ratio to lower values,both in competing nerve terminals and at postsynaptic sites,plays a relevant role in controlling the elimination of supernumerary ***,calcium entry through L-and P/Q-subtypes of voltage-gated calcium channels(both channels are present,together with the n-type channel in developing nerve terminals)contributes to red

关键词： acetylcholine release adenosine receptors axonal competition brain-derived neurotrophic factor calcium channels motor end-plate muscarinic acetylcholine receptors postnatal synapse elimination serine kinases tropomyosin-related kinase receptorB

Study of vertically ascending flight of a hawkmoth model

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Acta Mechanica Sinica 2020年第5期36卷 1031-1045,I0002页

作者： Anh Tuan nguyen vu Dan Thanh Le The Hung Tran v.n.Due van Binh Phung Faculty of Aerospace Engineering Le Quy Don Technical UniversityHanoiVietnam Institute of Theoretical and Applied Research.Duy Tan University HanoiVietnam Division of Construction Computation Institute for Computational ScienceTon Due Thang UniversityHo Chi Minh CityVietnam Faculty of Civil Engineering Ton Due Thang UniversityHo Chi Minh CityVietnam

This paper provides insight into the wing kinematics,the power requirement and the dynamic stability characteristics of a hawkmoth model in vertically ascending *** wing kinematics of the hawkmoth model is obtained based on the minimum required power *** optimization process is conducted using genetic and simplex algorithms that are coupled with an artificial neural network to rapidly predict the aerodynamic force and required *** training data for the neural network are generated from an unsteady vortex-lattice *** to hover,the results in this study show the larger flapping frequency and the smaller rotation amplitude of the hawkmoth wing kinematics in ascending ***,more power is required when the ascending speed *** conducting a dynamic modal analysis based on a cycle-average approach,the certain effect of the ascending speed on the modal structures of the hawkmoth model was observed.

关键词： Hawkmoth Ascending flapping flight-Genetic algorithm Artificial neural network Flight dynamic stability

Robust Finite-time H_∞ Control of Linear Time-varying Delay Systems with Bounded Control via Riccati Equations

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International Journal of Automation and computing 2018年第3期15卷 355-363页

作者： Piyapong niamsup vu n.Phat Department of Mathematics Faculty of Science Chiang Mai University Institute of Mathematics VAST

In this paper, we will present new results on robust finite-time H∞ control for linear time-varying systems with both time-varying delay and bounded control. Delay-dependent sufficient conditions for robust finite-time stabilization and H∞ control are first established to guarantee finite-time stability of the closed-loop system via solving Riccati differential equations. Applications to finite-time H∞ control to a class of linear autonomous time-delay systems with bounded control are also discussed in this *** examples are given to illustrate the effectiveness of the proposed method.

关键词： Finite-time stability H∞ control bounded control time-varying delay Riccati equation.

Hydrogeological Characteristics of a Karst Mountainous Catchment in the northwest of vietnam

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Acta Geologica Sinica(English Edition) 2001年第3期75卷 260-268页

作者： v.T.TAM T.M.n.vu O.BATELAAn Research Institute of Geology and Mineral Resources Ministry of Industry VietnamResearch Institute of Geology and Mineral Resources Ministry of Industry VietnamDepartment of Hydrology and Hydraulic Engineering Free University Brussels Belgium

This paper presents a preliminary assessment of the hydrogeological characteristics of a karst mountainous catchment, the Suoi Muoi River catchment, in the northwest of vietnam. The catchment is located at 600–700 m a.s.l. and covers an area of 284 km. Exposed limestone occupies 32% of the total catchment area. various types of assessments have been carried out, including geological and hydrogeological field surveys, cave surveys, dye-tracer tests, meteorological and surface water monitoring. Geological studies and cave surveys have identified the most important active cave/conduit systems within the catchment. Although these data are essential, they are insufficient to make a comprehensive appraisal of the hydrologic nature of the catchment under interest. An attempt was made to calculate a global water balance of the catchment, based on short-term (15 months) meteorological and streamflow records. The results show that, despite the existence of a number of substantial cavern conduit systems, the groundwater system of the catchment is governed by the fracture/fissure matrix. The cavern conduit systems only collect groundwater from the adjacent fracture matrix and/or connect topographically isolated surface watercourses. The groundwater storage of the cavern conduit systems appears to be regionally insignificant in comparison with the governed fracture matrix groundwater system.

关键词： karst hydrology geology lowflow

Modeling net-charge fluctuations in heavy-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.Eyyubova 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 intensive quantities D and Σ were used to remove the effects related to system volume *** employed two versions of HYDJET++for the *** first one is the standard or default version,whereas the second one is a modification that takes into account explicit event-by-event conservation of the electric net-charge of produced *** inclusion of the canonical net-charge conservation 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： relativistic heavy-ion collisions net-charge fluctuations strongly intensive variables canonical charge conservation