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Nano Research 2011年第7期4卷 666-674页

作者： Tiago luis da Silva Laudemir carlos Varanda Colloidal Materials Group Instituto de Quimica de Sao Carlos Universidade de Sao Paulo--USP Sao Carlos PO Box 780 13566-590 Brazil

The synthesis and self-assembly of tetragonal phase-containing L10-Fe55Pt45 nanorods with high coercive field is described. The experimental procedure resulted in a tetragonal/cubic phase ratio close to 1：1 for the as-synthesized nanoparticles. Using different surfactant/solvent proportions in the process allowed control of particle morphology from nanospheres to nanowires. Monodisperse nanorods with lengths of 60 ＋ 5 nm and diameters of 2-3 nm were self-assembled in a perpendicular oriented array onto a substrate surface using hexadecylamine as organic spacer. Magnetic alignment and properties assigned, respectively, to the shape anisotropy and the tetragonal phase suggest that the self-assembled materials are a strong candidate to solve the problem of random magnetic alignment observed in FePt nanospheres leading to applications in ultrahigh magnetic recording （UHMR） systems capable of achieving a performance of the order of terabits/in2.

关键词： Magnetic materials data storage FePt nanorods self-assembl~ perpendicular magnetic alignment

Muscle strength deficits are associated with low bone mineral density in young pediatric cancer survivors:The iBoneFIT project

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Journal of Sport and Health Science 2024年第3期13卷 419-427页

作者： Andres Marmol-Perez Jose J.Gil-Cosano Esther Ubago-Guisado Francisco J.Llorente-Cantarero Juan Francisco Pascual-Gázquez Kirsten K.Ness Vicente Martinez-Vizcaino Jonatan R.Ruiz luis Gracia-Marco Department of Physical Education and Sports Faculty of Sport SciencesSport and Health University Research Institute(iMUDS)University of GranadaGranada 18011Spain Department of Epidemiology and Cancer Control St.Jude Children's Research HospitalMemphisTN 38105USA Department of Communication and Education Loyola University AndalusiaSeville 41704Spain Biosanitary Research Institute ibs.GranadaGranada 18012Spain Maimonides Biomedical Research Institute of Cordoba(IMIBIC) Cordoba 14004Spain CIBEROBN Biomedical Research Networking Center for Physiopathology of Obesity and NutritionCarlos III Health InstituteMadrid 28029Spain Department of Specific Didactics Faculty of EducationUniversity of CordobaCordoba 14071Spain Pediatric and adolescent hematology and oncology service Pediatrics and Pediatric Surgery Clinical Management UnitVirgen de las Nieves University HospitalGranada 18014Spain Health and Social Research Center Universidad de Castilla-La ManchaCuenca 13001Spain

Background Pediatric cancer survivors are at increased risk of muscle weakness and low areal bone mineral density(aBMD).However,the prevalence of muscle strength deficits is not well documented,and the associations of muscle strength with aBMD are unknown in this ***,this study aimed to investigate the prevalence of upper-and lower-body muscle strength deficits and to examine the associations of upper-and lower-body muscle strength with age-,sex,and race-specific aBMD Z-scores at the total body,total hip,femoral neck,and lumbar *** This cross-sectional study included 116 pediatric cancer survivors(12.1±3.3 years old,mean±SD;42.2%female).Upper-and lower-body muscle strength were assessed by handgrip and standing long jump test,***‑energy X‑ray absorptiometry was used to measure aBMD(g/cm2).Associations between muscle strength and aBMD were evaluated in multivariable linear regression *** regression was used to evaluate the contribution of muscle strength(1-decile lower)to the odds of having low aBMD(Z-score≤1.0).All analyses were adjusted for time from treatment completion,radiotherapy exposure,and body mass *** More than one-half of survivors were within the 2 lowest deciles for upper-(56.9%)and lower-body muscle strength(60.0%)in comparison to age-and sex-specific reference *** strength deficits were associated with lower aBMD Z-scores at all sites(B=0.133–0.258,p=0.001–0.032).Each 1-decile lower in upper-body muscle strength was associated with 30%–95%higher odds of having low aBMD Z-scores at all *** 1-decile lower in lower-body muscle strength was associated with 35%–70%higher odds of having low aBMD Z-scores at total body,total hip,and femoral *** Muscle strength deficits are prevalent in young pediatric cancer survivors,and such deficits are associated with lower aBMD Z-scores at all *** results suggest that interventions designed to improve muscle strength in t

关键词： Bone health Childhood cancer DXA Lean mass Resistance training

Effect of Exogenous Melatonin on Seed Germination and Seedling Growth in Melon(Cucumis melo L.) Under Salt Stress

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Horticultural Plant Journal 2019年第2期5卷 79-87页

作者： José luis Casta?ares carlos Alberto Bouzo Plant Physiology Laboratory Department of Basic Sciences Universidad Nacional de Luján Laboratory of Research in Physiology and Plant Molecular Biology Facultad de Ciencias Agrarias Universidad Nacional del Litoral

An investigation was carried out to evaluate the effect of different application forms and concentrations of melatonin on germination and initial growth of melon plants in several different salinity conditions. We evaluated germination percentage and growth of seedlings and measured total chlorophyll content, relative electrolyte leakage, peroxidase activity, root viability, proline concentration, relative water content,Na^+/K^+ratio in green parts and K^+leakage from roots. Seed germination percentage under salt stress increased with treatments of 10 and50 μmol·L^(-1) melatonin. Seed treatment and plant watering with melatonin at 50 μmol·L^(-1) improved growth parameters and plants showed higher chlorophyll content as well as better biochemical parameters than non-treated plants. Results suggest that melatonin can alleviate the effect of salt stress during seed germination and first stages of plant development.

关键词： melon melatonin salt stress germination antioxidation

Fluidization of binary mixtures of sisal residue and sand:A new model for deriving the final fluidization velocity

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Particuology 2018年第5期16卷 10-22页

作者： David Vasconcelos Gabriele Batalha luis Gabriel Pereira carlos Augusto Pires Chemical Reaction Engineering Laboratory Federal University of Bahia40.210-910SalvadorBABrazil

The influence of different factors on the fiuidization of a binary mixture of sisal residue and sand was *** particle sizes of the sand and sisal residue were varied from 0.2to 0.8mm and the biomass mass fractions from 2% to 9%.Some segregation was noted,and a significant relationship was found among the final fluidization velocity (Uff),the biomass and sand sizes,and the biomass mass fraction.A novel model was developed for predicting Uff,leading to an average discrepancy of 12.69% between the measured and predicted Uff compared with the best match of 15.32% when using a model from a previous *** new model was applied to data from studies using other biomass and a broad range of particle *** average divergences from measured values when using the new model were 7.9% for corn cob and walnut shell,and 20.5% for sweet sorghum bagasse,tobacco residue, and soy *** were superior to the values derived using other *** results confirm the accuracy of the model developed in this work and show that it represents a viable alternative way to calculate Uff for a binary mixture of sand and biomass.

关键词： Fluidization Binary mixture Sisal residue Final fluidization velocity model

Factors affecting populations of the endemic Iberian hare(Lepus granatensis)after the first myxomatosis outbreaks in Central Spain

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Integrative Zoology 2023年第6期18卷 981-993页

作者： carlos LÁZARO Joséluis GUZMÁN Fabián CASAS carlos SÁNCHEZ-GARCÍA Department of Research Fundación ArtemisanCiudad RealSpain Department of Zoology Faculty of SciencesUniversity of GranadaGranadaSpain

The Iberian hare(Lepus granatensis)is an endemic species distributed in Spain and *** outbreaks affecting this species were detected in 2018 in Central and Southern Spain,spreading *** to evaluate factors affecting the status of hare population after the arrival of myxomatosis,we conducted 108 nocturnal hare counts in Central Spain during two study periods(winter/spring and summer/autumn)in 54 different hunting grounds,covering 1071 km and observing 884 *** mean density in winter/spring was 7.66 hares/100 ha,(range 6.14-9.54/100 ha),while in summer/autumn,it was 3.4 hares/100 ha(range 2.6-4.4/100 ha).Densities of hares were not affected by the dominant habitat and the presence/absence of myxomatosis *** were more abundant at hunting grounds at a higher altitude and in those conducting targeted management,while detection of myxomatosis was related to lower altitude and higher levels of game management.A MaxEnt model used to generate a risk map for myxomatosis occurrence showed that the temperature annual range was the most important predictor,which suggests that environmental factors affecting myxomatosis vectors(mosquitoes,fleas,and ticks)could play a key role in disease *** myxomatosis in hares is becoming endemic,hare densities may be improved by game management and the monitoring and surveillance of this emerging *** surveillance programs could be the basis of effective collaborations between hunters,researchers,and environmental managers.

关键词： game management habitat Iberian hare MaxEnt monitoring myxomatosis

Evaluation of p53 codon 72 polymorphism in adenocarcinomas of the colon and rectum in La Plata, Argentina

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World Journal of Gastroenterology 2006年第9期12卷 1426-1429页

作者： luis Orlando Pérez Martin carlos Abba Fernando Noel Dulout carlos Daniel Golijow Centro de Investigaciones en Genética Básica y Aplicada Facultad de Ciencias Veterinarias Universidad Nacional de La PlataCalle 60 y 118 S/NB 1900 AVWLa PlataArgentina

AIM： To evaluate the potential association between p53 codon 72 polymorphism and sporadic colorectal adenocarcinoma development, and human papillornavirus （HPV） infection. METHODS： One-hundred and nine controls and 53 patients with colon cancer from the city of La Plata, Argentina were analyzed, p53 codon 72 genotypes and HPV infection were identified using allele-specific polymerase chain reaction and nested polymerase chain reaction, respectively. RESULTS： The differences in the distribution ofp53 codon 72 polymorphisrn between the cases and controls were statistically significant. The arginine allele had a prevalence of 0.65 in controls and 0.77 in cases. The corresponding odds ratio for the homozygous arginine genotype was 2.08 （95% CI, 1.06-4.05; P〈0.05）. Lack of association was found between ,053 polymorphism and HPV infection in the set of adenocarcinomas. CONCLUSION： The findings of the present study indicate that p53 codon 72 arginine homozygous genotype may represent a genetic predisposing factor for colon cancer development. However, further studies are needed in order to elucidate the role of p53 codon 72 polymorphism in colorectal cancer.

关键词： p53 codon 72 polymorphism Human papillomavirus, Colorectal cancer

Attosecond twisted beams from high-order harmonicgeneration driven by optical vortices

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High Power Laser Science and Engineering 2017年第1期5卷 12-19页

作者： carlos Hernandez-Garcia Laura Rego Julio San Roman Antonio Picon luis Plaja Grupo de Investigacion en Aplicaciones del Laser y Fotonica Departamento de Fisica AplicadaUniversity of SalamancaE-37008SalamancaSpain Argonne National Laboratory Argonne1L 60439USA

Optical vortices are structures of the electromagnetic field with a spiral phase ramp about a point-phase singularity,carrying orbital angular momentum(OAM). Recently, OAM has been imprinted to short-wavelength radiation through high-order harmonic generation(HHG), leading to the emission of attosecond twisted beams in the extreme-ultraviolet(XUV) regime. We explore the details of the mapping of the driving vortex to its harmonic spectrum. In particular, we show that the geometry of the harmonic vortices is convoluted, arising from the superposition of the contribution from the short and long quantum paths responsible of HHG. Finally, we show how to take advantage of transverse phase-matching to select twisted attosecond beams with different spatiotemporal properties.

关键词： attosecond science extreme-ultraviolet vortices high harmonic generation orbital angular momentum twisted beams vortexbeams

Complex derivatives valuation: applying the Least-Squares Monte Carlo Simulation Method with several polynomial basis

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Financial Innovation 2016年第1期2卷 1-14页

作者： Ursula Silveira monteiro de Lima carlos Patricio Samanez Department of Industrial Engineering Pontifical Catholic University of Rio de JaneiroMarquês de São Vicente Street225/22453-900 GáveaRio de JaneiroBrazil

Background:This article investigates the Least-Squares Monte Carlo Method by using different polynomial basis in American Asian Options *** standard approach in the option pricing literature is to choose the basis *** comparing four different polynomial basis we show that the choice of basis interferes in the option's ***:We assess Least-Squares Method performance in pricing four different American Asian Options by using four polynomial basis:Power,Laguerre,Legendre and Hermite *** every American Asian Option priced,three sets of parameters are used in order to evaluate it ***:We show that the choice of the basis interferes in the option's price by showing that one of them converges to the option's value faster than any other by using fewer simulated *** the case of an Amerasian call option,for example,we find that the preferable polynomial basis is Hermite *** an Amerasian put option,the Power polynomial basis is *** empirical outcome is theoretically unpredictable,since in principle all basis can be indistinctly used when pricing the ***:In this article The Least-Squares Monte Carlo Method performance is assessed in pricing four different types of American Asian Options by using four different polynomial basis through three different sets of *** results suggest that one polynomial basis is best suited to perform the method when pricing an American Asian *** all basis can be indistinctly used when pricing the ***,our results does not confirm *** find that when pricing an American Asian put option,Power A is better than the other basis we have studied here whereas when pricing an American Asian call,Hermite A is better.

关键词： Complex derivatives valuation Least-Squares Monte Carlo Method Amerasian options Polynomial basis

Carbocysteine as Adjuvant Therapy in Acute Respiratory Tract Infections in Patients without Underlying Chronic Conditions: Systematic Review and Meta-Analysis

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Open Journal of Respiratory Diseases 2024年第2期14卷 39-50页

作者： Myriam Calle Rubio Olga de la Serna Blazquez José luis R. Martin Manuel Ruiz Cuetos Pulmonology Department Hospital Clínico San Carlos Madrid Spain Department of Medicine School of Medicine Universidad Complutense de Madrid Madrid Spain Instituto de Investigacion Sanitaria del Hospital Clínico San carlos (IdISSC) Madrid Spain Pediatric Pulmonology Unit Pediatrics Department Hospital Universitario La Paz Madrid Spain Simplifying Research Institute Layos Spain Medical department in ITF Research Pharma S.L.U. Alcobendas Spain

Objective: This study aims to systematically examine the existing evidence regarding the clinical benefits of carbocysteine as an adjunctive treatment in acute bronchopulmonary and otorhinological processes. Design: Systematic review and meta-analysis. Data sources: An electronic search was conducted across PubMed, Cochrane Library, ***, and the European Clinical Trial Register, with the search dated to May 2023. Bibliographic references from other literature reviews and meta-analyses were also reviewed. The search was limited to randomized clinical trials published in any language and year. It was completed by cross-checking the references of the located articles. Methods: Inclusion criteria covered studies assessing systemic or inhaled carbocysteine, regardless of dosing regimen. Concomitant medication use was acceptable if balanced between intervention and control groups. Authors independently extracted data, resolving disagreements through consensus. Methodological quality assessment relied on critical reading of each study. Dichotomous variables were analyzed using odds ratio (OR), and a final effect size was calculated. Statistical significance was established when confidence intervals did not cross the neutral value. Heterogeneity was assessed via the X2 test and I2 index. Results: Out of 318 initially identified studies, 4 met inclusion criteria. The meta-analysis for poor general condition yielded an OR of 0.45 in favor of intervention, p = 0.013, with non-significant heterogeneity. Cough events showed a percentage of 15.8% for carbocysteine vs. 27.2% for placebo. On the seventh day, expectoration rates were 18.37% for carbocysteinevs 33.3% for placebo. Conclusions: The observed clinical benefits align with carbocysteine’s mucoactive and muco-regulatory properties, complemented by anti-inflammatory and antioxidant actions. Carbocysteine stands out among mucolytic agents. In the context of persistent infectious diseases,

关键词： Acute Respiratory Infections Carbocystenine Systematic Review Meta-Analysis

Experimental analysis of infragravity waves in two eroded microtidal beaches

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Acta Oceanologica Sinica 2017年第5期36卷 31-43页

作者： MARIO Conde-Frias luis Otero JUAN Camilo Restrepo JUAN carlos Ortiz Geosciences Research Group GE04 Department of PhysicsUniversidad del NorteBarranquilla 081007Colombia

This work aims to contribute to the characterization and understanding ofinfragravity waves on two beaches with erosion problems. For this reason, we have used an array of ADCP and a pressure sensor to measure wave parameters and pressure inside and outside of the surf zone during the dry and rainy period in the beaches of Galerazamba and Manzanillo del Mar （both dissipative and eroded beaches） located in the Colombian Caribbean coast. Based on these measurements, we have carried out a spectral analysis in order to identify the frequency components that characterize the wave and its energy; thus, we identified the characteristic frequencies of iufragravity waves to finally filter the infragravity signal on each beach in different seasonal periods. Among the results of the Welch spectrum applied to surface elevation time series, we found that, the frequencies＇ energy of the sea-swell band decreases due to bottom friction and wave breaking as the wave approaches the shore, while the frequencies＇ energy of the infragravity band increases significantly. In addition, for the wavelet analysis, we could observe how the energy of the infragravity band, especially the lowest frequencies gain energy as the waves approaches the coast. Furthermore, based on the infragravity wave obtained from the extreme wave event registered during the field campaign we can conclude that the contribution of this signal is important in the erosion problems presented in the beaches of Galerazamba and Manzanillo del Mar. Finally, these results show the need to realize other studies that allow us to understand deeply, the role of infragravity waves on the morphological changes that occurs in these beaches.

关键词： infragravity waves long waves experimental analysis fourier analysis wavelet transform