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Synthesis and Characterization of Monodisperse Magnetite Hollow Microspheres

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Soft nanoscience Letters 2011年第2期1卷 25-32页

作者： Francisco Márquez Teresa Campo María Cotto ramón polanco Rolando Roque Pedro Fierro José María Sanz Eduardo Elizalde Carmen Morant Universidad Autónoma de Madrid University of Puerto Rico University of Turabo

Monodisperse hollow magnetite microspheres were successfully synthesized by an one-step process through a tem-plate-free hydrothermal approach employing simultaneously a mixture of FeCl3.6H2O and ferrocene as precursor and a propylene glycol-isopropanol mixture as solvent. The morphologies and properties of the magnetite microspheres were characterized by X-ray diffraction (XRD), raman and infrared spectroscopy, field emission scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS), adsorption of nitrogen (BET method) and SQUID magnetometry. The results show that the microspheres consist of a single crystalline phase of magnetite. On the other hand, the size and the internal hollow of the microspheres depend on the temperature of growth and can be tuned by modifying the synthesis conditions.

关键词： Fe3O4 Magnetite Hollow Spheres

A Generalized Array Factor for Time-Modulated Hexagonal Based Antenna Array Geometry With novel Trapezoidal Switching

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IEEE/CAA Journal of Automatica Sinica 2024年第9期11卷 1967-1972页

作者： Gopi ram Department of Electronics and Communication Engineering National Institute of TechnologyWarangal 506004India

The concept of the time-modulated array has been emerging as an alternative to the complex phase shifters,which lowers the cost of the array feeding network due to the utilization of radio frequency(RF)*** various forms of hexagonal antenna array geometries can be used for applications like surveillance tracking in phased array radar and wireless communication *** work proposes the generalized array factor(AF)for the hexagonal antenna array geometry based on time *** time modulation in generalized hexagonal geometry can maintain the fixed static amplitude excitation,giving more flexibility over ***,a novel trapezoidal switching function is also proposed and applied to the generalized array factor to enable future researchers to use this array factor in the field of advancement to observe how switching schemes like trapezoidal and rectangular affect the array pattern's side lobe level(SLL).The generalized equation can be utilized for the analysis and synthesis of radiation characteristics of the time-modulated hexagonal array(TMHA),time-modulated concentric hexagonal array(TMCHA),time-modulated hexagonal cylindrical array(TMHCA),and time-modulated hexagonal concentric cylindrical array(TMHCCA).The numerical result illustrates the generation of AF of time-modulated hexagonal structures and also shows that the trapezoidal switching sequence outperforms the rectangular switch using the cat swarm optimization(CSO)approach.

关键词： Hexagonal array geometry radiation pattern time-modulation trapezoidal pulse

A Probabilistic Trust Model and Control Algorithm to Protect 6G networks against Malicious Data Injection Attacks in Edge Computing Environments

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Computer Modeling in Engineering & Sciences 2024年第10期141卷 631-654页

作者： Borja Bordel Sánchez ramón Alcarria Tomás Robles Department of Computer Systems Universidad Politécnica de MadridMadrid28031Spain Department of Geospatial Engineering Universidad Politécnica de MadridMadrid28031Spain

Future 6G communications are envisioned to enable a large catalogue of pioneering *** will range from networked Cyber-Physical Systems to edge computing devices,establishing real-time feedback control loops critical for managing Industry 5.0 deployments,digital agriculture systems,and essential *** provision of extensive machine-type communications through 6G will render many of these innovative systems autonomous and *** full automation will enhance industrial efficiency significantly,it concurrently introduces new cyber risks and *** particular,unattended systems are highly susceptible to trust issues:malicious nodes and false information can be easily introduced into control ***,Denialof-Service attacks can be executed by inundating the network with valueless *** anomaly detection schemes require the entire transformation of the control software to integrate new steps and can only mitigate anomalies that conform to predefined mathematical *** based on an exhaustive data collection to detect anomalies are precise but extremely *** models,with their limited understanding of mobile networks,can achieve precision rates no higher than 75%.Therefore,more general and transversal protection mechanisms are needed to detect malicious behaviors *** paper introduces a probabilistic trust model and control algorithm designed to address this *** model determines the probability of any node to be *** channels are pruned for those nodes whose probability is below a given *** trust control algorithmcomprises three primary phases,which feed themodel with three different probabilities,which are weighted and ***,anomalous nodes are identified using Gaussian mixture models and clustering ***,traffic patterns are studied using digital Bessel functions and the functional scalar ***,the in

关键词： 6G networks noise injection attacks Gaussian mixture model Bessel function traffic filter Volterra filter

Wood anatomical acclimation in the endemic genus Polylepis in Peruvian Andean forests

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Journal of Mountain Science 2024年第9期21卷 2986-3000页

作者： Anthony GUERRA Fressia n.AMES-MARTÍnEZ Ernesto C.RODRÍGUEZ-ramÍREZ Postgraduate Programme in Agronomy/Plant Physiology Department of Biology-Institute of natural Sciences Federal University of LavrasLavras 37203-202Minas Gerais 30000-31999Brazil Laboratory of Biotechnology and Molecular Biology Continental UniversitySan Antonio UrbanizationHuancayo 12000Peru Ecology and Biodiversity Research Programme ANDINUS AssociationMiguel Grau Street 370Huancayo 12000Peru Dendrochronology Laboratory Continental UniversitySan Carlos Avenue 1980Huancayo 12000Peru

Polylepis(Queñua)is a dominant woody plant genus in Andean Puna forests that occurs in a wide range of montane habitats and is ecologically diverse in endemism,which may be particularly threatened by climate *** anatomical traits are essential for understanding how plants adjust their ecophysiological requirements and maximize their resilience,resistance,and recovery to extreme *** the effects of extreme climatic conditions in high altitude ecosystems have been studied extensively,our knowledge is relatively limited to quantitative differences in the main xylem *** address this gap,we assessed the acclimation of wood anatomical traits in six Peruvian Andean Polylepis species with different water availability(semi-dry with high moisture and semiarid with dry winters).We selected hydraulic diameter,vessel density,vessel grouping index,solitary vessel index,vulnerability index,mesomorphy index,vessel element length,fiber length,fiber wall thickness,fiber lumen diameter,and total fiber diameter that can provide relevant eco-wood anatomical acclimation to hydric *** performed multivariate analysis to determine the leading dimensions of covariation among Polylepis species and climatic *** wood anatomical traits(vessel grouping index,vulnerability index,and fiber wall thickness)were dissimilar between xeric-and mesic-Polyelpis *** study demonstrates that wood anatomical traits in Peruvian Andean Polylepis species provides high-resolution and long-term eco-wood anatomical signals on how climate oscillations drive the acclimation processes of fiber and vessel *** findings underscore the significance of xylem hydraulic adjustment to various hydrological environments in Andean puna *** evaluating the effects of drought on wood anatomical characteristics and ecological function,we demonstrate the capacity of tree species to adapt and endure climate-related changes,thereby emphasizing their resilience and ada

关键词： Carlquist indices Climatic resilience Vessel traits Fiber Functional trait Hydric stress

Seedling potential of trees species along the elevational gradient in temperate hill forest of central nepal

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Journal of Mountain Science 2024年第4期21卷 1329-1344页

作者： DAnI ram Sharan BAnIYA Chitra Bahadur Central Department of Botany Tribhuvan UniversityKirtipur 44618Nepal

Regeneration status of tree species along elevation gradient in temperate hill forest was not understood *** research examined the tree diversity and its regeneration patterns along an elevation gradient in temperate hill forest,central *** were collected from 300 sample plots within vertical elevation bands of 10,ranging from 1365 to 2450 m asl.A random sampling method was used for data collection in three seasons,winter,pre-monsoon and post monsoon *** at breast height(DBH)was used to broadly categorize the plant individual into trees,saplings and *** tree species richness ranged from 12 to 25 with density of 350 to 1200 individuals per *** richness of tree and sapling showed statistically significant unimodal pattern,which peaked at *** showed a strong and positive linear correlation with the seedling density(Deviance=0.99,pnd a significant hump-shaped relationship with sapling density(Deviance=0.95,pns showed a statistically significant negative hump-shaped relationship with all trees,saplings and seedling stages(Deviances=0.89,0.87 and 0.57).The highest values of the Shannon-Wiener index and the lowest value of the Simpson index were found at mid-elevation for all growth *** 92%of tree species were found at regenerating stage;49%in a good renewal regeneration status,32%in fair renewal regeneration,and 11%at a poor regenerating ***,4%of tree species were reported as non-regenerating stages and 4%were newly introduced ***,the regeneration status of the study area was considered fairly well since sapling(78.5%)>seedling(10.6%)≤mature(10.9%).Among tested environmental variables,elevation and annual mean rainfall were the most influential factors in the regeneration of tree species.

关键词： Regeneration potential Chandragiri hill Altitudinal gradient Species diversity Tree species richness

Development of novel 5-FU modified siRnA against BCL-2 with enhanced efficacy and vehicle-free cellular uptake

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Genes & Diseases 2024年第1期11卷 23-25页

作者： Andrew Fesler Ga-ram Hwang Jingfang Ju Department of Pathology Renaissance School of MedicineStony Brook UniversityStony BrookNY 11794USA The northport Veteran's Administration Medical Center NorthportNY 11768USA Curamir Therapeutics Inc. WoburnMA 01801USA

One of the major obstacles for nucleic acid-based medicine is cellular uptake due to the concern of efficiencyand potential toxicity of the *** this work,we developed a novel approach to eliminate the need for a vehicle to allow for the cellular uptake of siRnA-based therapy with a unique modification strategy that also further enhances therapeutic *** discovery may be of great importance for the development of siRnA-based therapeutics as cellular uptake remains a critical *** this study,we have tested the potential of this modification strategy for siRnA using a siRnA that targets B-cell lymphoma-2(BCL-2).

关键词： eliminate uptake modified

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)

Implementation of blockchain technology in integrated IoT networks for constructing scalable ITS systems in India

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Blockchain(Research and Applications) 2024年第2期5卷 99-125页

作者： Arya Kharche Sanskar Badholia ram Krishna Upadhyay School of Technology Gati Shakti VishwavidyalayaVadodaraGujarat390004India

The implementation of blockchain technology in integrated IoT networks for constructing scalable Intelligent Transportation Systems(ITSs)in India has the potential to revolutionize the way we approach *** leveraging the power of IoT and blockchain,we can create a highly secure,transparent,and efficient system that can transform the way we move people and ***,one of the world’s most populous countries,has a highly congested and inefficient transportation system that often leads to delays,accidents,and waste of time and *** integration of IoT and blockchain can help address these issues by enabling real-time monitoring,tracking,and optimization of traffic flows,thereby reducing congestion,improving safety,and increasing the overall efficiency of the transportation *** paper explores the potential of blockchain technology in the context of integrated IoT networks for constructing scalable ITS systems in *** methodology followed is to develop a proof-of-concept blockchain-based application for ITS,implement the blockchain solution into the existing ITS infrastructure,and ensure proper integration and compatibility with other *** thorough research and maintenance to ensure the reliability and sustainability of such blockchain-based *** research discusses the various benefits and challenges of this approach and the various applications of this technology in the transportation sector,including the green sustainability *** results find various ways in which such implementations of blockchain and IoT-Machine Learning(IoT-ML)can revolutionize transportation systems.

关键词： Transportation systems IoT Blockchain Machine learning Safety

MicroRnA-630:A promising avenue for alleviating inflammation in diabetic kidney disease

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World Journal of Diabetes 2024年第7期15卷 1398-1403页

作者： Javier Donate-Correa Ainhoa González-Luis Jésica Díaz-Vera Juan ramón Hernandez-Fernaud Research Unit University Hospital Nuestra Señora de Candelaria(UHNSC)Santa Cruz de Tenerife 38010Spain Department of Biochemistry MicrobiologyCell Biology and GeneticsInstituto de Tecnologías BiomédicasUniversidad de La LagunaSanta Cruz de Tenerife 38000Spain

Diabetic kidney disease(DKD)is one of the complications of diabetes,affecting millions of people *** relentless progression of this condition can lead to kidney failure,requiring life-altering interventions such as dialysis or *** evidence suggests that immunologic and inflammatory elements play an important role in initiating and perpetuating the damage inflicted on renal tissues,exacerbating the decline in organ ***-like receptors(TLRs)are a family of receptors that play a role in the activation of the innate immune system by the recognition of pathogen-associated molecular *** data from in vitro and in vivo studies have highlighted the critical role of TLRs,mainly TLR2 and TLR4,in the pathogenesis of *** the diabetic milieu,these TLRs recognize diabetic-associated molecular signals,triggering a proinflammatory cascade that initiates and perpetuates inflammation and fibrogenesis in the diabetic *** non-traditional strategies targeting TLR signaling with potential therapeutic implications in DKD have been *** of these approaches is the use of microRnAs,small non-coding RnAs that can regulate gene *** editorial comments on the results of this approach carried out in a rat model of diabetes by Wu et al,published in this issue of the World Journal of *** results of the experimental study by Wu et al shows that microRnA-630 decreased levels compared to non-diabetic ***,microRnA-630 exerted anti-inflammatory effects in the kidneys of diabetic rats through the modulation of *** findings indicate that the microRnA-630/TLR4 axis might represent a pathological mechanism of DKD and a potential therapeutic target capable of curbing the destructive inflammation characteristic of DKD.

关键词： Diabetes Diabetic kidney disease Inflammation Toll-like receptor 4 microRnA-630