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Geometric and Photometric Data Fusion in Non-Rigid Shape Analysis

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Numerical mathematics(Theory,methods and Applications) 2013年第1期6卷 199-222页

作者： Artiom Kovnatsky Dan Raviv michael m.bronstein alexander m.bronstein Ron Kimmel Institute of Computational Science Faculty of InformaticsUniversitàdella Svizzera ItalianaLuganoSwitzerland School of Electrical Engineering Tel Aviv UniversityIsrael Technion–Israel Institute of Technology Computer Science DepartmentHaifaIsrael

In this paper,we explore the use of the diffusion geometry framework for the fusion of geometric and photometric information in local and global shape *** construction is based on the definition of a diffusion process on the shape manifold embedded into a high-dimensional space where the embedding coordinates represent the photometric *** results show that such data fusion is useful in coping with different challenges of shape analysis where pure geometric and pure photometric methods fail.

关键词： Laplace-Beltrami operator diffusion equation heat kernel descriptors 3D shape retrieval deformation invariance

Assessment of the heartwood contribution to carbon accumulation in Pinus sylvestris L. trees under different forest site conditions

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FOREST ECOSYSTEmS 2025年第1期12卷 159-175页

作者： Galibina, Natalia A. Nikerova, Kseniya m. moshnikov, Sergey A. Kryshen, alexander m. Russian Acad Sci Forest Res Inst Karelian Res Ctr 11 Pushkinskaya St Petrozavodsk 185910 Karelia Russia

Background: The heartwood (HW) proportion in the trunk of mature trees is an important characteristic not only for wood quality but also for assessing the role of forests in carbon sequestration. We have for the first time studied the proportion of HW in the trunk and the distribution of carbon and extractives in sapwood (SW) and HW of 70-80 year old Pinus sylvestris L. trees under different growing conditions in the pine forests of North-West Russia. method: We have examined the influence of conditions and tree position in stand (dominant, intermediate and suppressed trees) in the ecological series: blueberry pine forest (Blu) - lingonberry pine forest (Lin) - lichen pine forest (Lic). We have analyzed the influence of climate conditions in the biogeographical series of Lin: the middle taiga subzone - the northern taiga subzone - the transition area of the northern taiga subzone and tundra. Results: We found that the carbon concentration in HW was 1.6%-3.4% higher than in SW, and the difference depended on growing conditions. Carbon concentration in HW increased with a decrease in stand productivity (Blu-Lin-Lic). In medium-productive stands, the carbon concentration in SW was higher in intermediate and supressed trees compared to dominant trees. In the series from south to north, carbon concentration in HW increased by up to 2%, while in SW, it rose by 2.7%-3.8%. Conclusions: Our results once again emphasized the need for an empirical assessment of the accurate carbon content in aboveground wood biomass, including various forest growing conditions, to better understand the role of boreal forests in carbon storage.

关键词： Scots pine Blueberry pine forest Lingonberry pine forest Lichen pine forest Tree social class Climate Carbon content Extractives Cellulose Lignin

microglia:a promising therapeutic target in spinal cord injury

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Neural Regeneration Research 2025年第2期20卷 454-463页

作者： Xiaowei Zha Guoli Zheng Thomas Skutella Karl Kiening Andreas Unterberg alexander Younsi Department of Neurosurgery Heidelberg University HospitalHeidelbergGermany Department of Neuroanatomy Institute for Anatomy and Cell BiologyHeidelberg UniversityHeidelbergGermany

microglia are present throughout the central nervous system and are vital in neural repair,nutrition,phagocytosis,immunological regulation,and maintaining neuronal *** a healthy spinal cord,microglia are accountable for immune surveillance,however,when a spinal cord injury occurs,the microenvironment drastically changes,leading to glial scars and failed axonal *** this context,microglia vary their gene and protein expression during activation,and proliferation in reaction to the injury,influencing injury responses both favorably and unfavorably.A dynamic and multifaceted injury response is mediated by microglia,which interact directly with neurons,astrocytes,oligodendrocytes,and neural stem/progenitor *** a clear understanding of their essential nature and origin,the mechanisms of action and new functions of microglia in spinal cord injury require extensive *** review summarizes current studies on microglial genesis,physiological function,and pathological state,highlights their crucial roles in spinal cord injury,and proposes microglia as a therapeutic target.

关键词： astrocytes cytokines functional recovery immune regulation m1/m2 activation macrophages microglia neuroinflammation spinal cord injury therapy

Reinforcement Learning in mechatronic Systems: A Case Study on DC motor Control

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Circuits and Systems 2025年第1期16卷 1-24页

作者： alexander Nüßgen alexander Lerch René Degen marcus Irmer martin de Fries Fabian Richter Cecilia Boström margot Ruschitzka CAD CAm Center Cologne Institute of Automotive Engineering Cologne (IFK) Faculty of Automotive Systems and Production Cologne University of Applied Science Cologne Germany Division of Electricity Department of Electrical Engineering Uppsala University Uppsala Sweden Heringer Consulting GmbH Cologne Germany

The integration of artificial intelligence into the development and production of mechatronic products offers a substantial opportunity to enhance efficiency, adaptability, and system performance. This paper examines the utilization of reinforcement learning as a control strategy, with a particular focus on its deployment in pivotal stages of the product development lifecycle, specifically between system architecture and system integration and verification. A controller based on reinforcement learning was developed and evaluated in comparison to traditional proportional-integral controllers in dynamic and fault-prone environments. The results illustrate the superior adaptability, stability, and optimization potential of the reinforcement learning approach, particularly in addressing dynamic disturbances and ensuring robust performance. The study illustrates how reinforcement learning can facilitate the transition from conceptual design to implementation by automating optimization processes, enabling interface automation, and enhancing system-level testing. Based on the aforementioned findings, this paper presents future directions for research, which include the integration of domain-specific knowledge into the reinforcement learning process and the validation of this process in real-world environments. The results underscore the potential of artificial intelligence-driven methodologies to revolutionize the design and deployment of intelligent mechatronic systems.

关键词： Artificial Intelligence in Product Development mechatronic Systems Reinforcement Learning for Control System Integration and Verification Adaptive Optimization Processes Knowledge-Based Engineering

Probing multi-mobility edges in quasiperiodic mosaic lattices

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Science Bulletin 2025年第1期70卷 58-63页

作者： Jun Gao Ivan m.Khaymovich Xiao-Wei Wang Ze-Sheng Xu Adrian Iovan Govind Krishna Jiayidaer Jieensi Andrea Cataldo alexander V.Balatsky Val Zwiller Ali W.Elshaari Department of Applied Physics KTH Royal Institute of TechnologyAlbanova University CentreStockholm SE-10691Sweden Nordita Stockholm University and KTH Royal Institute of TechnologyStockholm SE-10691Sweden Institute for Physics of microstructures Russian Academy of SciencesNizhny Novgorod 603950Russia Center for Integrated Quantum Information Technologies(IQIT) School of Physics and Astronomy and State Key Laboratory of Advanced Optical Communication Systems and NetworksShanghai Jiao Tong UniversityShanghai 200240China Department of Physics University of ConnecticutStorrsConnecticut 06269USA

The mobility edge(mE)is a crucial concept in understanding localization physics,marking the critical transition between extended and localized states in the energy *** localization scaling theory predicts the absence of mE in lower dimensional ***,the search for exact mEs,particularly for single particles in lower dimensions,has recently garnered significant interest in both theoretical and experimental studies,resulting in notable ***,several open questions remain,including the possibility of a single system exhibiting multiple mEs and the continual existence of extended states,even within the strong disorder ***,we provide experimental evidence to address these questions by utilizing a quasiperiodic mosaic lattice with meticulously designed nanophotonic *** observations demonstrate the coexistence of both extended and localized states in lattices with broken duality symmetry and varying modulation *** single-site injection and scanning the disorder level,we could approximately probe the mE of the modulated *** results corroborate recent theoretical predictions,introduce a new avenue for investigating mE physics,and offer inspiration for further exploration of mE physics in the quantum regime using hybrid integrated photonic devices.

关键词： mobility edge Localization physics mosaic lattice Nanophotonics

Assessment of the heartwood contribution to carbon accumulation in Pinus sylvestris L. trees under different forest site conditions

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Forest Ecosystems 2025年第1期 159-175页

作者： Natalia A.Galibina Kseniya m.Nikerova Sergey A.moshnikov alexander m.Kryshen Forest Research Institute of the Karelian Research Centre of the Russian Academy of Sciences

Background: The heartwood(HW) proportion in the trunk of mature trees is an important characteristic not only for wood quality but also for assessing the role of forests in carbon sequestration. We have for the first time studied the proportion of HW in the trunk and the distribution of carbon and extractives in sapwood(SW) and HW of 70–80 year old Pinus sylvestris L. trees under different growing conditions in the pine forests of North-West ***: We have examined the influence of conditions and tree position in stand(dominant, intermediate and suppressed trees) in the ecological series: blueberry pine forest(Blu)–lingonberry pine forest(Lin)–lichen pine forest(Lic). We have analyzed the influence of climate conditions in the biogeographical series of Lin: the middle taiga subzone–the northern taiga subzone–the transition area of the northern taiga subzone and ***: We found that the carbon concentration in HW was 1.6%–3.4% higher than in SW, and the difference depended on growing conditions. Carbon concentration in HW increased with a decrease in stand productivity(Blu-Lin-Lic). In medium-productive stands, the carbon concentration in SW was higher in intermediate and supressed trees compared to dominant trees. In the series from south to north, carbon concentration in HW increased by up to 2%, while in SW, it rose by 2.7%–3.8%.Conclusions: Our results once again emphasized the need for an empirical assessment of the accurate carbon content in aboveground wood biomass, including various forest growing conditions, to better understand the role of boreal forests in carbon storage.

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Vegetation dynamics at the southern edge of the Siberian mountain taiga

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Journal of mountain Science 2025年第2期22卷 451-465页

作者： Im Sergei T KHARUK Viacheslav I PETROV Il'ya A SHUSHPANOV alexander S DVINSKAYA maria L ONDAR Sergei O V.N.Sukachev Institute of Forest Krasnoyarsk Science Centre of the Siberian Branch of Russian Academy of ScienceKrasnoyarsk 660036Russia Institute of Ecology and Geography Institute of Space and Information TechnologiesSiberian Federal UniversityKrasnoyarsk 660041Russia Laboratory of Biodiversity and Ecology Tomsk State UniversityTomsk 634050Russia Institute of Space Research and High Technologies Reshetnev Siberian State University of Science and TechnologyKrasnoyarsk 660014Russia Department of Biology and Ecology Tuvan State UniversityKyzyl 667000Russia

The growth,survival,and mortality of conifer species in response to the hydrothermal regime have received considerable *** is expected that the highest sensitivity of trees to the warming-drying climate will occur mainly at the edges of the species *** focused on the responses to climate change of the drought-resistant larch(Larix sibirica)and the moisture-sensitive Siberian pine(Pinus sibirica)along the elevation gradient in the Tannu-Ola Ridge,the southern margin where those two species coexist in Siberia by using satellite data(mODIS,Landsat,and microwave),the indexes of gross(GPP)and net(NPP)primary productivity,and tree radial growth index(GI).We found that since the warming restart in the 2000s,the area of larch-dominated forests increased by~150%while the area of pine-dominated forests decreased by~10%.The Siberian pine has retreated at low elevations(m)and increased its area at higher *** contrast,the area of larch stands increased in both the uphill and downhill ***(Betula spp.)also increased its area at low elevations(about+120%).Since 2001,the forested area increased by~5%.A shrubification,i.e.,an increase in the area of shrubs,was observed at high *** uphill rate of timberline and shrubline migration was about 0.3 m/*** the 2000s,vegetation NPP has increased by 13%.A notable correlation between NPP and the GI of larch and pine was found(r=0.5-0.7).At lower elevations,NPP positively correlated with precipitation and soil moisture,while air temperature and VPD(vapor pressure deficit)increase inhibited *** high elevations,the effects of these variables on productivity *** continuous decline of the Siberian pine forest indicates an inevitable retreat of this species at low elevations and its replacement by larch and birch.

关键词： Trees range changes mountain taiga Siberian larch Siberian pine Timberline Shrubification Tree uphill migration Forest population dynamics Ecological resilience Habitat suitability

Hepatoprotective actions of melatonin:Possible mediation by melatonin receptors

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World Journal of Gastroenterology 2010年第48期16卷 6087-6097页

作者： alexander m mathes Department of Anesthesiology Critical Care and Pain MedicineSaarland University Hospital

melatonin,the hormone of darkness and messenger of the photoperiod,is also well known to exhibit strong direct and indirect antioxidant properties. melatonin has previously been demonstrated to be a powerful organ protective substance in numerous models of injury; these beneficial effects have been attributed to the hormone's intense radical scavenging capacity. The present report reviews the hepatoprotective potential of the pineal hormone in various models of oxidative stress in vivo,and summarizes the extensive literature showing that melatonin may be a suitable experimental substance to reduce liver damage after sepsis,hemorrhagic shock,ischemia/reperfusion,and in numerous models of toxic liver injury. melatonin's influence on hepatic antioxidant enzymes and other potentially relevant pathways,such as nitric oxide signaling,hepatic cytokine and heat shock protein expression,are evaluated. Based on recent literature demonstrating the functional relevance of melatonin receptor activation for hepatic organ protection,this article finally suggests that melatonin receptors could mediate the hepatoprotective actions of melatonin therapy.

关键词： Antioxidant enzymes Hemorrhagic shock Hepatoprotection Ischemia Liver Liver function melatonin melatonin receptor Ramelteon Reperfusion Sepsis Toxic liver injury

Treating amyotrophic lateral sclerosis with allogeneic Schwann cell-derived exosomal vesicles: a case report

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Neural Regeneration Research 2025年第4期20卷 1207-1216页

作者： Pascal J.Goldschmidt-Clermont Aisha Khan George Jimsheleishvili Patricia Graham Adriana Brooks Risset Silvera alexander J.P.Goldschmidt Damien D.Pearse W.Dalton Dietrich Allan D.Levi James D.Guest miller School of medicine University of MiamiMiamiFLUSA Stem Cell Institute Miller School of MedicineUniversity of MiamiMiamiFLUSA The miami Project to Cure Paralysis Miller School of MedicineUniversity of MiamiMiamiFLUSA Alzady International LLC MiamiFLUSA Neurological Surgery Miller School of MedicineUniversity of MiamiMiamiFLUSA

Schwann cells are essential for the maintenance and function of motor neurons,axonal networks,and the neuromuscular *** amyotrophic lateral sclerosis,where motor neuron function is progressively lost,Schwann cell function may also be ***,important signaling and potential trophic activities of Schwann cell-derived exosomal vesicles have been *** case report describes the treatment of a patient with advanced amyotrophic lateral sclerosis using serial intravenous infusions of allogeneic Schwann cell-derived exosomal vesicles,marking,to our knowledge,the first instance of such *** 81-year-old male patient presented with a 1.5-year history of rapidly progressive amyotrophic lateral *** initial diagnosis,the patient underwent a combination of generic riluzole,sodium phenylbutyrate for the treatment of amyotrophic lateral sclerosis,and *** patient volunteered to participate in an FDA-approved single-patient expanded access treatment and received weekly intravenous infusions of allogeneic Schwann cell-derived exosomal vesicles to potentially restore impaired Schwann cell and motor neuron *** confirmed that cultured Schwann cells obtained from the amyotrophic lateral sclerosis patient via sural nerve biopsy appeared impaired(senescent)and that exposure of the patient’s Schwann cells to allogeneic Schwann cell-derived exosomal vesicles,cultured expanded from a cadaver donor improved their growth capacity in *** a period of observation lasting 10 weeks,during which amyotrophic lateral sclerosis Functional Rating Scale-Revised and pulmonary function were regularly monitored,the patient received weekly consecutive infusions of 1.54×1012(×2),and then consecutive infusions of 7.5×1012(×6)allogeneic Schwann cell-derived exosomal vesicles diluted in 40 mL of Dulbecco’s phosphate-buffered *** of the infusions were associated with adverse events such as infusion reactions(allergic or otherwise)or

关键词： allogeneic amyotrophic lateral sclerosis exosomes infusion neuromuscular junction Schwann cell