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In-situ study of the microstructure evolution during tension of a Mg-Y-Zn-Al alloy processed by rapidly solidified ribbon consolidation technique

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Journal of Magnesium and Alloys 2024年第5期12卷 2024-2040页

作者： Jeno Gubicza Kristián Máthis péter Nagy péter Jenei Zoltán Hegedus Andrea Farkas Jozef Vesely Shin-ichi Inoue Daria Drozdenko Yoshihito Kawamura Department of Materials physics Faculty of ScienceEotvos Loránd UniversityPázmány P.sétány 1/ABudapest H-1117Hungary Department of physics of Materials Faculty of Mathematics and PhysicsCharles UniversityKe Karlovu 512116 Praha 2Czech Republic Deutsches Elektronen-Synchrotron DESY Notkestr.85Hamburg 22603Germany Magnesium Research Center Kumamoto University2-39-1 KurokamiChuo-kuKumamoto 860-8555Japan

Mg-Y-Zn-Al alloys processed by rapidly solidified ribbon consolidation(RSRC)technique exhibit an exceptional mechanical performance indicating promising application *** material has a bimodal microstructure consisting of fine recrystallized and coarse non-recrystallized grains with solute-rich stacking faults forming cluster arranged layers(CALs)and nanoplates(CANaps),or complete long period stacking ordered(LpSO)*** order to reveal the deformation mechanisms,in-situ synchrotron X-ray diffraction line profile analysis was employed for a detailed study of the dislocation arrangement created during tension in Mg-0.9%Zn-2.05%Y-0.15%Al(at%)*** uncovering the effect of the initial microstructure on the mechanical performance,additional samples were obtained by annealing of the as-consolidated specimen at 300 and 400℃ for 2 *** heat treatment at 300℃ had no significant effect on the initial microstructure,its evolution during tension and,thus,the overall deformation behavior under tensile *** the other hand,annealing at 400℃ resulted in a significant increase of the recrystallized grains fraction and a decrease of the dislocation density,leading to only minor degradation of the mechanical *** maximum dislocation density at the failure of the samples corresponding to the plastic strain of 10-25% was estimated to be about 16-20×10^(14)m^(-2).The diffraction profile analysis indicated that most dislocations formed during tension were of non-basal and pyramidal types,what was also in agreement with the Schmid factor values revealed independently from orientation *** was also shown that the dislocation-induced Taylor hardening was much lower below the plastic strain of 3% than above this value,which was explained by a model of the interaction between prismatic dislocations and CANaps/LpSO plates.

关键词： Mg-Zn-Y-Al alloy Long period stacking ordered(LpSO)phase Cluster arranged nanoplates(CANaps) Annealing Tension Dislocation density Hardening

From single to combinatorial therapies in spinal cord injuries for structural and functional restoration

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Neural Regeneration Research 2025年第3期20卷 660-670页

作者： Ernesto Doncel-pérez Gabriel Guízar-Sahagún Israel Grijalva-Otero Hospital Nacional de parapléjicos de Toledo Servicio de Salud de Castilla La Mancha(SESCAM)ToledoSpain Medical Research Unit for Neurological Diseases UMAE Hospital de EspecialidadesCentro Médico Nacional Siglo XXIIMSSCiudad de MéxicoMéxico

Spinal cord injury results in paralysis, sensory disturbances, sphincter dysfunction, and multiple systemic secondary conditions, most arising from autonomic dysregulation. All this produces profound negative psychosocial implications for affected people, their families, and their communities;the financial costs can be challenging for their families and health institutions. Treatments aimed at restoring the spinal cord after spinal cord injury, which have been tested in animal models or clinical trials, generally seek to counteract one or more of the secondary mechanisms of injury to limit the extent of the initial damage. Most published works on structural/functional restoration in acute and chronic spinal cord injury stages use a single type of treatment: a drug or trophic factor, transplant of a cell type, and implantation of a biomaterial. Despite the significant benefits reported in animal models, when translating these successful therapeutic strategies to humans, the result in clinical trials has been considered of little relevance because the improvement, when present, is usually insufficient. Until now, most studies designed to promote neuroprotection or regeneration at different stages after spinal cord injury have used single treatments. Considering the occurrence of various secondary mechanisms of injury in the acute and sub-acute phases of spinal cord injury, it is reasonable to speculate that more than one therapeutic agent could be required to promote structural and functional restoration of the damaged spinal cord. Treatments that combine several therapeutic agents, targeting different mechanisms of injury, which, when used as a single therapy, have shown some benefits, allow us to assume that they will have synergistic beneficial effects. Thus, this narrative review article aims to summarize current trends in the use of strategies that combine therapeutic agents administered simultaneously or sequentially, seeking structural and functional restoratio

关键词： neural regeneration neuroprotection spinal cord injury repair spinal cord injury treatments structural restoration of spinal cord injury

Spastin and alsin protein interactome analyses begin to reveal key canonical pathways and suggest novel druggable targets

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Neural Regeneration Research 2025年第3期20卷 725-739页

作者： Benjamin R.Helmold Angela Ahrens Zachary Fitzgerald p.Hande Ozdinler Department of Neurology Feinberg School of MedicineNorthwestern UniversityChicagoILUSA Center for Molecular Innovation and Drug Discovery Center for Developmental TherapeuticsChemistry of Life Processes InstituteNorthwestern UniversityEvanstonILUSA Mesulam Center for Cognitive Neurology and Alzheimer’s Disease Feinberg School of MedicineNorthwestern UniversityChicagoILUSA Feinberg School of Medicine Les Turner ALS Center at Northwestern UniversityChicagoILUSA

Developing effective and long-term treatment strategies for rare and complex neurodegenerative diseases is challenging. One of the major roadblocks is the extensive heterogeneity among patients. This hinders understanding the underlying disease-causing mechanisms and building solutions that have implications for a broad spectrum of patients. One potential solution is to develop personalized medicine approaches based on strategies that target the most prevalent cellular events that are perturbed in patients. Especially in patients with a known genetic mutation, it may be possible to understand how these mutations contribute to problems that lead to neurodegeneration. protein–protein interaction analyses offer great advantages for revealing how proteins interact, which cellular events are primarily involved in these interactions, and how they become affected when key genes are mutated in patients. This line of investigation also suggests novel druggable targets for patients with different mutations. Here, we focus on alsin and spastin, two proteins that are identified as “causative” for amyotrophic lateral sclerosis and hereditary spastic paraplegia, respectively, when mutated. Our review analyzes the protein interactome for alsin and spastin, the canonical pathways that are primarily important for each protein domain, as well as compounds that are either Food and Drug Administration–approved or are in active clinical trials concerning the affected cellular pathways. This line of research begins to pave the way for personalized medicine approaches that are desperately needed for rare neurodegenerative diseases that are complex and heterogeneous.

关键词： ALS2 alsin amyotrophic lateral sclerosis hereditary spastic paraplegia neurodegenerative diseases personalized medicine precision medicine protein interactome protein-protein interactions SpAST spastin

Groundwater uptake of different surface cover and its consequences in great Hungarian plain

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Ecological processes 2017年第1期6卷 408-416页

作者： Zoltán Gribovszki péter Kalicz Kitti Balog András Szabó Tibor Tóth péter Csáfordi Mohamed Metwaly Sándor Szalai Institute of Geomatics and Civil Engineering University of SopronSopronHungary Institute for Soil Sciences and Agricultural Chemistry Centre for Agricultural ResearchHungarian Academy of SciencesBudapestHungary Forest Research Institute National Agricultural Research and Innovation CentreBudapestHungary Archaeology Department College of Tourism and ArchaeologyKing Saud UniversityRiyadhSaudi Arabia National Research Institute of Astronomy and Geophysics(NRIAG) CairoEgypt MTA CSFK GGI SopronHungary

Introduction:Forest cover in Hungary has increased from 1.1 to 2.0 million hectares during the last *** EU(European Union)promotes further afforestation;thus,15,000–18,000 ha are being forested each year,mainly in the Hungarian Great *** terms of species used for afforestation,poplar plantations are preferred over native oak *** groundwater uptake of trees can be a significant water balance element of forested areas in shallow groundwater environments within the Hungarian Great *** can cause water table depressions and subsurface salt accumulation in areas with negative water *** study examined the hydrological impact of forest cover in the Hungarian Great *** the framework of this research,climatic water balance,water table depth and salinity,subsoil layering,tree species and stand age were analysed as influencing *** paper compares the effect which an oak forest,a poplar plantation and a pasture have on groundwater uptake and salt ***:The water table level was roughly 0.4–0.5 m lower beneath the oak forest and the poplar plantation than it was beneath the *** groundwater use was 1.5–2 times higher than that of *** uptake of oak forest was greater than that of poplar plantation during the monitoring *** accumulation,which shows water use in the longer run,was slightly higher for poplar in deeper ***:The greater amount of groundwater used by trees does not lead to a higher salt uptake as only a slight accumulation of salt was measured beneath the ***,hybrid poplar was slightly less favourable than native oak when considering salinization ***,even greater groundwater uptake by trees over longer timescales could cause more significant salt accumulation under pronounced drought conditions due to climate change.

关键词： Groundwater recharge/water budget Evapotranspiration Diurnal fluctuation Forest cover Salinization

Ultra-flat twisted superlattices in 2D heterostructures

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npj Computational Materials 2020年第1期6卷 909-914页

作者： Márton Szendrő péter Süle Gergely Dobrik Levente Tapasztó Institute of Technical physics and Materials Science(MFA) Centre for Energy ResearchHungarian Academy of SciencesP.O.Box 49Budapest 1525Hungary

Moiré-superlattices are ubiquitous in 2D heterostructures,strongly influencing their electronic *** give rise to new Dirac cones and are also at the origin of the superconductivity observed in magic-angle bilayer *** modulation amplitude(corrugation)is an important yet largely unexplored parameter in defining the properties of 2D *** generally accepted view is that the corrugation monotonically decreases with increasing twist angle,while its effects on the electronic structure diminish as the layers become progressively decoupled.

关键词： properties cor twisted

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)

CYp24A1 inhibition facilitates the anti-tumor effect of vitamin D3 on colorectal cancer cells

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World Journal of Gastroenterology 2013年第17期19卷 2621-2628页

作者： János p Kósa péter Horváth János Wlfling Dóra Kovács Bernadett Balla péter Mátyus Evelin Horváth Gábor Speer István Takács Zsolt Nagy Henrik Horváth péter Lakatos 1 st Department of Internal Medicine Semmelweis University Department of Organic Chemistry University of Szeged Department of Organic Chemistry Semmelweis University

AIM:The effects of vitamin D3 have been investigated on various tumors, including colorectal cancer (CRC). 25-hydroxyvitamin-D3-24-hydroxylase (CYp24A1), the enzyme that inactivates the active vitamin D3 metabolite 1,25-dihydroxyvitamin D3 (1,25-D3), is considered to be the main enzyme determining the biological halflife of 1,25-D3. During colorectal carcinogenesis, the expression and concentration of CYp24A1 increases significantly, suggesting that this phenomenon could be responsible for the proposed efficacy of 1,25-D3 in the treatment of CRC. The aim of this study was to investigate the anti-tumor effects of vitamin D3 on the human CRC cell line Caco-2 after inhibition of the cytochrome p450 component of CYp24A1 activity. METHODS:We examined the expression of CYp24A1 mRNA and the effects of 1,25-D3 on the cell line Caco-2 after inhibition of CYp24A1. Cell viability and proliferation were determined by means of sulforhodamine-B staining and bromodeoxyuridine incorporation, respectively, while cytotoxicity was estimated via the lactate dehydrogenase content of the cell culture supernatant. CYp24A1 expression was measured by realtime reverse transcription polymerase chain reaction. A number of tetralone compounds were synthesized to investigate their Cp24A1 inhibitory activity. RESULTS:In response to 1,25-D3, CYp24A1 mRNA expression was enhanced significantly, in a time- and dose-dependent manner. Caco-2 cell viability and proliferation were not influenced by the administration of 1,25-D3 alone, but were markedly reduced by coadministration of 1,25-D3 and KD-35, a CYp24A1-inhibiting tetralone. Our data suggest that the mechanism of action of co-administered KD-35 and 1,25-D3 does not involve a direct cytotoxic effect, but rather the inhibition of cell proliferation. CONCLUSION:These findings demonstrate that the selective inhibition of CYp24A1 by compounds such as KD-35 may be a new approach for enhancement of the anti-tumor effect of 1,25-D3 on CRC.

关键词： Colorectal cancer CYp24A1 inhibition Vitamin D3 Tetralone derivatives Caco-2 cell culture

Iterative signal reconstruction of deliberately clipped SMT signals

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Science China(Information Sciences) 2014年第2期57卷 5-17页

作者： KOLLR Zsolt GAZDA Juraj HORVTH pter VARGA Lajos KOCUR Duan Budapest University of Technology and Economics Technical University of Koice

Staggered MultiTone(SMT)is a modulation technique showing significantly reduced Adjacent Channel Leakage Ratio(ACLR)resulting in a more compact power Spectrum Density(pSD)for the transmitted signal,than the well-known and already widely adopted Orthogonal Frequency Division Multiple Access(OFDMA)***,the unique spectral properties of an SMT signal could be degraded by a non-linear element(e.g.a power Amplifier(pA))in the *** baseband clipping can be applied to the transmitted signal,reducing the notable high peak-to-Average power Ratio(pApR).The objective of this paper is to give a brief introduction to the SMT scheme,with a special emphasis on deliberate clipping efects and their *** paper introduces two receiver-oriented iterative methods aiming at the restoration of the baseband Bit Error Rate(BER)performance of a non-clipped *** methods are evaluated and compared based on numerical *** paper concludes with the selection of a possible candidate for use in systems applying deliberately clipped SMT signals.

关键词： clipping SMT iterative decoding nonlinear distortion pApR

Enantioselectivity of the Musk Odor Sensation

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复旦学报（自然科学版） 2005年第5期44卷 775-776页

作者： G. Fráter p. Kraft Givaudan Schweiz AG Fragrance Researchberlandstrasse 138 CH-8600 Dübendorf SwitzerlandGivaudan Schweiz AG Fragrance Researchberlandstrasse 138 CH-8600 Dübendorf Switzerland

Chiral recognition of substrates is one of the most characteristic phenomena of biological activity. And one of the most fundamental biological activities of chemical substances is their smell. In 1991, Linda Buck and Richard Axel[1] discovered a large multigene family that en codes odorant receptors, for which they were awarded the 2004 Nobel prize in Medicine and physiology. These odorant receptors are highly homologous,consist of ca. 320 amino acids, and show a heptahelical transmembrane structure as typical for G-protein-coupled receptors. In the human genome, 347 putative full-length olfactory receptor genes have been identified,which allow via characteristic activation patterns of the associated glomeruli the differentiation of more than 10 000 odorants. Since the odorant receptors are built from enantiomerically pure amino acids, they are themselves chiral. Consequently, one would expect a strong diastereomeric interaction, and enantiomeric pairs of odorants should thus differ significantly in both their odor character and their strengths or odor threshold.

关键词：对映体大环麝香气味感受器手性识别