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Towards 5th Generation Wireless Communication Systems

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ZTE Communications 2015年第1期13卷 11-19页

作者： nicola marchetti CTVR/Telecommunications Research Centre Trinity College Dublin

This paper introduces the general landscape of next-generation wireless communication systems （5G）, including the impetus and requirements of 5G and the candidate technologies that might help 5G achieve its goals. The following areas, which the author considers particularly relevant, are discussed： deteetion of and access to free spectrum over bands of a heterogeneous nature, ex- treme densification of networks （massive base station deployments）, extreme increase in the number of antennas in base station ar- rays and their interaction with a novel waveform, integration of both wireless and optical sides of telecom networks, and study of wireless networks from the perspective of complex systems science. The author discusses recent research conducted by his team in each of these research areas.

关键词： 5G spectrum cell densification efficiency optical wireless integration

Real-time estimation of the structural utilization level of segmental tunnel lining

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Underground Space 2024年第4期17卷 132-145页

作者： nicola Gottardi Steffen Freitag Gunther Meschke Institute for Structural Mechanics Ruhr University BochumBochum 44801Germany Institute for Structural Analysis Karlsruhe Institute of TechnologyKarlsruhe 76131Germany

Over the last decades,an expansion of the underground network has been taking place to cope with the increasing amount of moving people and *** a consequence,it is of vital importance to guarantee the full functionality of the tunnel network by means of preventive maintenance and the monitoring of the tunnel lining state over time.A new method has been developed for the real-time prediction of the utilization level in tunnel segmental linings based on input monitoring *** new concept is founded on a framework,which encompasses an offline and an online *** the former,the generation of feedforward neural networks is accomplished by employing synthetically produced *** element simulations of the lining structure are conducted to analyze the structural response under multiple loading *** scenarios are generated by assuming ranges of variation of the model input parameters to account for the uncertainty due to the not fully determined in situ *** and target quantities are identified to better assess the structural utilization of the *** latter phase consists in the application of the methodological framework on input monitored data,which allows for a real-time prediction of the physical quantities deployed for the estimation of the lining *** approach is validated on a full-scale test of segmental lining,where the predicted quantities are compared with the actual ***,it is investigated the influence of artificial noise added to the training data on the overall prediction performances and the benefits along with the limits of the concept are set out.

关键词： Segmental lining Artificial neural networks Structural utilization level Real-time prediction Structural health monitoring Monitoring data

A high-order target phase approach for the station-keeping of periodic orbits

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Astrodynamics 2024年第1期8卷 61-75页

作者： Xiaoyu Fu nicola Baresi Roberto Armellin Surrey Space Centre University of SurreyGuildfordGU27XHUK Te PūnahaĀtea-Auckland Space Institute University of AucklandAuckland1010New Zealand

A novel high-order target phase approach(TPhA)for the station-keeping of periodic orbits is proposed in this *** key elements of the TPhA method,the phase-angle Poincare map and high-order maneuver map,are constructed using differential algebra(DA)techniques to determine station-keeping epochs and calculate correction maneuvers.A stochastic optimization framework tailored for the TPhA-based station-keeping process is leveraged to search for fuel-optimal and error-robust TPhA ***-satellite orbits(QSOs)around Phobos are investigated to demonstrate the efficacy of TPhA in mutli-fidelity dynamical *** Carlo simulations demonstrated that the baseline QSO of JAXA’s Martian Moons eXploration(MMX)mission could be maintained with a monthly maneuver budget of approximately 1 m/s.

关键词： target phase approach(TPhA) station-keeping Poincarémap differential algebra(DA) quasi-satellite orbit(QSO)

The potential for an old-growth forest to store carbon in the topsoil:A case study at Sasso Fratino,Italy

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Journal of Forestry Research 2024年第2期35卷 23-32页

作者： Tommaso Chiti nicola Benilli Giovanni Mastrolonardo Giacomo Certini Dipartimento per la Innovazione nei Sistemi Biologici Agroalimentari e Forestali(DIBAF)Universitàdella TusciaVia San C.de Lellis Snc01100 ViterboItaly Dipartimento di Scienze e Tecnologie Agrarie AlimentariAmbientali e Forestali(DAGRI)Universitàdegli Studi di FirenzeP.le delle Cascine 1850144 FirenzeItaly

There is considerable interest devoted to oldgrowth forests and their capacity to store carbon(C)in biomass and *** of C stocks in old-growth forests are carried out worldwide,although there is a lack of information on their actual potential for C *** further understand this,soil organic carbon(SOC)was measured in one of Italy's best-preserved old-growth forests,the Sasso Fratino Integral Nature *** reserve is on the World Heritage List along with other ancient beech forests of Europe,and it is virtually untouched due to the steepness of the terrain,even before legal constraints were *** the sandstone-derived soils are often shallow,they are rich in organic ***,no quantification had been carried *** systematically sampling the topsoil across the forest,we accurately determined the average amount of SOC(62.0±16.9 Mg ha^(–1))and nitrogen(4.0±1.2 Mg ha^(–1))in the top 20 *** the CENTURY model,future dynamics of SOC stocks were predicted to 2050 according to two climate scenarios,A1F1 and B2,the first of high concern and the second more *** model projected an increase of 0.2 and 0.3 Mg ha^(–1)a^(–1)by 2030 under the A1F1 and B2 scenarios,respectively,suggesting that the topsoil in old-growth forests does not reach equilibrium but continues accumulating ***,from 2030 to 2050,a decline in SOC accumulation is predicted,indicating SOC net loss at high altitudes under the worst-case *** study confirms that soils in oldgrowth forests play a significant role in carbon *** also suggests that climate change may affect the potential of these forests to store SOC not only in the long term but also in the coming years.

关键词： Carbon sequestration CENTURY model Climate change Forest soil Soil nitrogen

Risk of hepatitis B virus reactivation in oncological patients treated with tyrosine kinase inhibitors:A case report and literature analysis

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World Journal of Gastroenterology 2024年第9期30卷 1253-1256页

作者： Francesca Colapietro nicola Pugliese Antonio Voza Alessio Aghemo Stella De nicola Department of Biomedical Sciences Humanitas UniversityMilan 20072Italy Division of Internal Medicine and Hepatology Department of GastroenterologyHumanitas Research HospitalMilan 20089Italy Department of Emergency Humanitas Research HospitalMilan 20089Italy

Hepatitis B virus(HBV)reactivation(HBVr)represents a severe and potentially life-threatening condition,and preventive measures are available through blood test screening or prophylactic therapy *** assessment of HBVr traditionally considers factors such as HBV profile,including hepatitis B surface antigen(HBsAg)and antibody to hepatitis B core antigen,along with type of medication(chemotherapy;immunomodulants).Nevertheless,consideration of possible patient’s underlying tumor and the specific malignancy type(solid or hematologic)plays a crucial role and needs to be assessed for decision-making process.

关键词： Chronic hepatitis B Reactivation Nucleoside analogue Tyrosine kinase inhibitors Onco-hematology

Brain dysfunctions and neurotoxicity induced by psychostimulants in experimental models and humans:an overview of recent findings

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Neural Regeneration Research 2024年第9期19卷 1908-1918页

作者： Marcello Serra nicola Simola Alexia E.Pollack Giulia Costa Department of Biomedical Sciences Section of NeuroscienceUniversity of CagliariCagliariItaly Department of Biology University of Massachusetts-BostonBostonMAUSA

Preclinical and clinical studies indicate that psychostimulants,in addition to having abuse potential,may elicit brain dysfunctions and/or neurotoxic *** toxicity induced by psychostimulants may pose serious health risks since the recreational use of these substances is on the rise among young people and *** present review provides an overview of recent research,conducted between 2018 and 2023,focusing on brain dysfunctions and neurotoxic effects elicited in experimental models and humans by amphetamine,cocaine,methamphetamine,3,4-methylenedioxymethamphetamine,methylphenidate,caffeine,and *** elucidation of factors and mechanisms that underlie psychostimulant-induced brain dysfunction and neurotoxicity is crucial for understanding the acute and enduring noxious brain effects that may occur in individuals who use psychostimulants for recreational and/or therapeutic purposes.

关键词： 3,4-methylenedioxymethamphetamine amphetamine caffeine cell cultures cocaine methamphetamine methylphenidate neurotoxicity nicotine

Increased number of symptoms during the acute phase of SARS-CoV-2 infection in athletes is associated with prolonged time to return to full sports performance—AWAREⅧ

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Journal of Sport and Health Science 2024年第3期13卷 280-287,I0001页

作者： Carolette Snyders Marlise Dyer nicola Sewry Esme Jordaan Martin Schwellnus Sport Exercise Medicine and Lifestyle Institute(SEMLI)Faculty of Health SciencesUniversity of PretoriaPretoria 0083South Africa Section Sports Medicine Faculty of Health SciencesUniversity of PretoriaPretoria 0083South Africa IOC Research Centre of South Africa Pretoria 0083South Africa Biostatistics Unit South African Medical Research CouncilTygerberg 7505South Africa Statistics and Population Studies Department University of the Western CapeCape Town 7535South Africa

Purpose The aim of the study was to identify factors associated with prolonged time to return to full performance(RTFP)in athletes with recent severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)*** Prospective cohort study with cross sectional analysis.A total of 84 athletes with confirmed SARS-CoV-2 infection assessed at a coronavirus disease 2019 recovery clinic gave a history of age,sex,type/level of sport,co-morbidities,pre-infection training hours,and 26 acute SARS-CoV-2 symptoms from 3 categories(“nose and throat”,“chest and neck”,and“whole body”/systemic).Data on days to RTFP were obtained by structured *** associated with RTFP were demographics,sport participation,history of co-morbidities,pre-infection training history,and acute symptoms(type,number).Outcomes were:(a)days to RTFP(median,interquartile range(IQR))in asymptomatic(n=7)and symptomatic athletes(n=77),and(b)hazard ratios(HRs;95%confidence interval)for symptomatic athletes with *** a factor(univariate,multiple models).HR0.05).Factors associated with prolonged RTFP(univariate models)were:females(HR=0.57;p=0.014),endurance athletes(HR=0.41;p<0.0001),co-morbidity number(HR=0.75;p=0.001),and respiratory disease history(HR=0.54;p=0.026).In symptomatic athletes,prolonged RTFP(multiple models)was significantly associated with increased“chest and neck”(HR=0.85;p=0.017)and“nose and throat”(HR=0.84;p=0.013)symptoms,but the association was more profound between prolonged RFTP and increased total number of“all symptoms”(HR=0.91;p=0.001)and“whole body”/systemic(HR=0.82;p=0.007)*** A larger number of total symptoms and specifically“whole body”/systemic symptoms during the acute phase of SARS-CoV-2 infection in athletes is associated with prolonged RTFP.

关键词： Athletes COVID-19 Performance Recovery Return to play

Organic petrographic and mineralogical composition of the No. 6 coal seam of the Soutpansberg Coalfield, South Africa: Insights into paleovegetation and depositional environment

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International Journal of Coal Science & Technology 2024年第3期11卷 190-207页

作者： Sanki Biswas nicola J.Wagner Ofentse M.Moroeng DSI-NRF CIMERA/PPM Research Group Department of GeologyUniversity of JohannesburgJohannesburgSouth Africa

This study investigates the paleodepositional conditions of the No.6 Seam of the Madzaringwe Formation in Makhado and Voorburg south area of the Soutpansberg Coalfield(Limpopo Province,South Africa)utilizing organic petrography and inorganic geochemical *** coals are predominantly high-volatile bituminous B-A rank with high ash yields(avg.36.1 wt%),characterized by high-vitrinite(~41.5 vol%),moderate-to-high inertinite(9.8 vol%–33.7 vol%)and low liptinite(~2.3 vol%).The distribution of inertinite varies among different coal horizons(from bottom-lower to middle-upper),suggesting differential oxidation conditions and/or paleofire ***-to-inertinite(V/I)ratio,tissue preservation–gelification index(TPI–GI),and groundwater–vegetation index(GWI–VI)plots,indicate that the peat-forming forest-swamp vegetation accumulated under mesotrophic-to-rheotrophic hydrological *** presence of structured macerals(i.e.,telinite,collotelinite,fusinite,and semifusinite)suggests well-preserved plant tissues,whereas framboidal pyrite and sulphur content(0.24 wt%–2.16 wt%)point to brackish-water influence at the peat *** coals contain quartz,kaolinite,siderite,muscovite,dolomite,calcite,and pyrite minerals,most of which were likely sourced from felsic igneous *** Al/(Al+Fe+Mn)and(Fe+Mn)/Ti ratios for the studied samples range between 0.24–0.97 and 0.57–70.10,*** ratios,Al–Fe–Mn plot,and presence of massive botryoidal-type pyrite imply some influence of meteoric waters or fluids from hydrothermal activity ***,the chemical index of alteration(CIA:98.25–99.67),chemical index of weathering(CIW:92.04–97.66),and A–CN–K ternary diagram suggest inorganic matter suffered strong chemical weathering,indicating warm paleoclimatic conditions during the coal formation.

关键词： Macerals Coal facies Geochemical-indices Hydrothermal Madzaringwe formation Soutpansberg Coalfield

Opto-fluidically multiplexed assembly and micro-robotics

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Light(Science & Applications) 2024年第3期13卷 544-554页

作者： Elena Erben Weida Liao Antonio Minopoli nicola Maghelli Eric Lauga Moritz Kreysing Max Planck Institute of Molecular Cell Biology and Genetics Dresden 01307Germany Center for Systems Biology Dresden 01307Germany Institute of Biological and Chemical Systems–Biological Information Processing.Karlsruhe Institute of Technology(KIT) Eggenstein-Leopoldshafen 76344Germany Department of Applied Mathematics and Theoretical Physics University of CambridgeCambridge CB30WAUK

Techniques for high-definition micromanipulations,such as optical tweezers,hold substantial interest across a wide range of ***,their applicability remains constrained by material properties and laser *** while microfluidic manipulations have been suggested as an alternative,their inherent capabilities are limited and further hindered by practical challenges of implementation and *** we show that the iterative application of laser-induced,localized flow fields can be used for the relative positioning of multiple micro-particles,irrespectively of their material *** to the standing theoretical proposal,our method keeps particles mobile,and we show that their precision manipulation is non-linearly accelerated via the multiplexing of temperature stimuli below the heat diffusion *** resulting flow fields are topologically rich and mathematically *** represent unprecedented microfluidic control capabilities that are illustrated by the actuation of humanoid micro-robots with up to 30 degrees of freedom,whose motions are sufficiently well-defined to reliably communicate personal characteristics such as gender,happiness and *** results constitute high-definition micro-fluidic manipulations with transformative potential for assembly,micro-manufacturing,the life sciences,robotics and optohydraulically actuated micro-factories.

关键词： manipulation fluid assembly