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Applications of finite element simulation in orthopedic and trauma surgery

World Journal of Orthopedics 2012年第4期3卷 25-41页

作者： antonio Herrera Elena Ibarz José Cego?ino antonio Lobo-Escolar sergio Puértolas Enrique López Jesús Mateo Luis Gracia Department of Orthopaedic and Trauma Surgery Miguel Servet University HospitalMedicine SchoolUniversity of Zaragoza Department of Mechanical Engineering University of Zaragoza

Research in different areas of orthopedic and trauma surgery requires a methodology that allows both a more economic approach and the ability to reproduce different situations in an easy way. Simulation models have been introduced recently in bioengineering and could become an essential tool in the study of any physiological unity, regardless of its complexity. The main problem in modeling with finite elements simulation is to achieve an accurate reproduction of the anatomy and a perfect correlation of the different structures, in any region of the human body. Authors have developed a mixed technique, joining the use of a three-dimensional laser scanner Roland Picza captured together with computed tomography(CT) and 3D CT images, to achieve a perfect reproduction of the anatomy. Finite element(FE) simulation lets us know the biomechanical changes that take place after hipprostheses or osteosynthesis implantation and biological responses of bone to biomechanical changes. The simulation models are able to predict changes in bone stress distribution around the implant, so allowing preventing future pathologies. The development of a FE model of lumbar spine is another interesting application of the simulation. The model allows research on the lumbar spine, not only in physiological conditions but also simulating different load conditions, to assess the impact on biomechanics. Different degrees of disc degeneration can also be simulated to determine the impact on adjacent anatomical elements. Finally, FE models may be useful to test different fixation systems, i.e., pedicular screws, interbody devices or rigid fixations compared with the dynamic ones. We have also developed models of lumbar spine and hip joint to predict the occurrence of osteoporotic fractures, based on densitometric determinations and specific biomechanical models, including approaches from damage and fracture mechanics. FE simulations also allow us to predict the behavior of orthopedic splints applied

关键词： Finite element simulation Hip prosthesis Lumbar spine Lumbar fixations Osteoporotic fractures Splints

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Integration of high-rate filtration using waste-derived biochar as a potential sustainable technology for drinking water supply

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Biochar 2023年第1期5卷 1075-1097页

作者： Fernando García-Ávila Andrés Galarza-Guamán Mónica Barros-Bermeo Emigdio antonio Alfaro-Paredes Alex Avilés-Añazco sergio lglesias-Abad Carrera de Ingeniería Ambiental Facultad de Ciencias QuímicasUniversidad de CuencaCuencaEcuador Departamento de Química Aplicada y Sistemas de Producción Grupo de Evaluación de Riesgos Ambientales en Sistemas de Producción y Servicios(RISKEN)CuencaEcuador Professional School of Systems Engineering Research Institute of Science and TechnologyUniversidad César VallejoLimaPeru Carrera de Ingeniería Ambiental Universidad Católica de CuencaCuencaEcuador

This research aimed to evaluate the efficiency of eucalyptus(E)and bamboo(B)residual biomass biochars as filter materials for drinking water *** efficiencies of these two biochars in the rapid filtration process were evaluated using water(raw,flocculated and settled)at the rate of 120 m^(3)/m^(2)/*** that bamboo biochar manufactured under a slow pyrolysis process"b"(Bb)had the best ***,Bb was evaluated with three different granulometries,and it was found that the effective size with the best performance was the finest(0.6-1.18 mm).Subsequently,this biochar was compared with conventional filter materials such as gravel,sand and anthracite,using different types of water(raw,flocculated and settled)and at different filtration rates(120 and 240 m^(3)/m^(2)/d),and it was found that the filter material with the best performance was precisely biochar,with average removal efficiencies of 64.37%turbidity and 45.08%colour for raw water;93.9%turbidity and 90.75%colour for flocculated water,and 80.79%turbidity and 69.03%colour for settled *** efficiency using simple beds of sand,biochar,anthracite and gravel at the rate of 180 m^(3)/m^(2)/d was 75.9%copper,90.72%aluminium,95.7%iron,10.9%nitrates,94.3%total coliforms and 88.9%fecal *** efficiencies achieved by biochar were higher compared to those of conventional filter *** was also found that biochar contributes to improving the performance of sand and anthracite in mixed ***,it was possible to demonstrate that the volume of washing water required for the biochar is lower compared to the other filter ***,it is recommended to carry out more tests for the purification of water with biochars from rural areas affected by the mining and oil exploitation,as well as the purification of seawater with biochars from coastal areas with residues from dry forests and organic residues from municipalities.

关键词： Biochar Filter medium Rapid filtration Pyrolysis Eucalyptus Bamboo

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Transient Power and Quality Events Analysed Using Hilbert Transforms

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Journal of Energy and Power Engineering 2012年第2期6卷 230-239页

作者： Mario Ortiz sergio Valero antonio Gabaldon Department of Mechanical and Energy Engineering Universidad Miguel Hern6ndez Alieante 03202 Spain Department of Electrical Engineering Universidad Politdcnica de Cartagena Murcia 30202 Spain

This work presents an advanced mathematical tool applicable to the recognition and classification of power system transients and disturbances. Disturbances without a periodic pattern or with a non-linear pattern require a more suitable tool than the Fourier series （Fast Fourier or Windowed Fourier Transforms）. To overcome these drawbacks, other tools have been broadly used, such as the wavelet transform. However, the wavelet transform also has some drawbacks such as the lack of adaptivity or interpretation of nonlinear phenomena that the Hilbert and Hilbert Huang Transform techniques could mitigate. The Hilbert techniques transform a time domain function into a space representation both in time and frequency. In the paper, the technique is applied to analyse several short-term and steady events, like a short circuit, a capacitor-switching transient, or a line energisation, showing the abilities of the Hilbert-based transforms.

关键词： Power system transients wavelet transform power quality Hilbert transform Hilbert Huang transform empirical modedecomposition.

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Tree growth is more limited by drought in rear-edge forests most of the times

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Forest Ecosystems 2021年第2期8卷 330-344页

作者： J.Julio Camarero antonio Gazol Gabriel Sangüesa-Barreda Marta Vergarechea Raquel Alfaro-Sánchez Nicolás Cattaneo sergio M.Vicente-Serrano Instituto Pirenaico de Ecología(IPE-CSIC) Avda.Montañana 1005E-50192 ZaragozaSpain Ei FAB-iu FOR University of ValladolidCampus Duques de SoriaE-42004 SoriaSpain NIBIO Norwegian Institute of Bioeconomy ResearchPostboks 155NO-1431ÅsNorway Department of Biology Wilfrid Laurier UniversityN2L 3C575 Univ.Avenue WWaterlooOntarioCanada

Background:Equatorward,rear-edge tree populations are natural monitors to estimate species vulnerability to climate *** to biogeographical theory,exposition to drought events increases with increasing aridity towards the equator and the growth of southern tree populations will be more vulnerable to drought than in central ***,the ecological and biogeographical margins can mismatch due to the impact of ecological factors(topography,soils)or tree-species acclimation that can blur large-scale geographical imprints in trees responses to drought making northern populations more drought ***:We tested these ideas in six tree species,three angiosperms(Fagus sylvatica,Quercus robur,Quercus petraea)and three gymnosperms(Abies alba,Pinus sylvestris and Pinus uncinata)by comparing rear-edge tree populations subjected to different degrees of *** used dendrochronology to compare the radial-growth patterns of these species in northern,intermediate,and southern tree populations at the continental rear *** and conclusions:We found marked variations in growth variability between species with coherent patterns of stronger drought signals in the tree-ring series of the southern populations of ***,***,and *** was also observed in species from cool-wet sites(*** and ***),despite their limited responsiveness to ***,in the case of *** the intermediate population showed the strongest relationship to *** drought-sensitive species as *** and ***,southern populations presented more variable growth which was enhanced by cool-wet conditions from late spring to *** found a trend of enhanced vulnerability to drought in these two *** response of tree growth to drought has a marked biogeographical component characterized by increased drought sensitivity in southern populations even within the species distribution rear ***,the relationship

关键词： Climate change Dendroecology Latitudinal gradient Mediterranean forests Standardized evapotranspiration precipitation index(SPEI)

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Plant adaptation to low phosphorus availability:Core signaling,crosstalks,and applied implications

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Molecular Plant 2022年第1期15卷 104-124页

作者： Javier Paz-Ares Maria Isabel Puga Monica Rojas-Triana Iris Martinez-Hevia sergio Diaz Cesar Poza-Carrión Miguel Mi(n)ambres antonio Leyva Department of Plant Molecular Genetics Centro Nacional de Biotecnología(CNB-CSIC)Darwin 3Campus Universidad Autónoma28049 MadridSpain Institute of Plant Biochemistry Institute of Synthetic Biology and CEPLASUniversity of Düsseldorf40225 DüsseldorfGermany

Phosphorus(P)is an essential nutrient for plant growth and *** preferentially absorb P as orthophosphate(Pi),an ion that displays low solubility and that is readily fixed in the soil,making P limita-tion a condition common to many soils and Pi fertilization an inefficient *** cope with Pi limitation,plants have evolved a series of developmental and physiological responses,collectively known as the Pi starvation rescue system(PSR),aimed to improve Pi acquisition and use efficiency(PUE)and protect from Pi-starvation-induced *** research has been carried out during the last 20 years to un-ravel the mechanisms underlying the control of the PSR in *** we review the results of this research effort that have led to the identification and characterization of several core Pi starvation signaling components,including sensors,transcription factors,microRNAs(miRNAs)and miRNA inhibitors,kinases,phosphatases,and components of the proteostasis *** also refer to recent results revealing the existence of intricate signaling interplays between Pi and other nutrients and antagonists,N,Fe,Zn,and As,that have changed the initial single-nutrient-centric view to a more integrated view of nutrient ***,we discuss advances toward improving PUE and future research priorities.

关键词： inositol pyrophosphate plant nutrient PHR1 transcription factor PUE(phosphorus acquisition and use efficiency) SPX sensor and STOP1 transcription factor

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Small intestine bacterial overgrowth and irritable bowel syndrome-related symptoms:Experience with Rifaximin

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World Journal of Gastroenterology 2009年第21期15卷 2628-2631页

作者： sergio Peralta Claudia Cottone Tiziana Doveri Piero Luigi Almasio antonio Craxi Operative Unit of Gastroenterology and Hepatology

AIM： TO estimate the prevalence of small intestinal bacterial overgrowth （SIBO） in our geographical area （Western Sicily, Italy） by means of an observational study, and to gather information on the use of locally active, non-absorbable antibiotics for treatment of SIBO.METHODS： Our survey included 115 patients fulfilling the Rome II criteria for diagnosis of irritable bowel syndrome （IBS）; a total of 97 patients accepted to perform a breath test with lactulose （BTLact）, and those who had a positive test, received Rifaximin （Normix , Alfa Wassermann） 1200 mg/d for 7 d; 3 wk after the end of treatment, the BTLact was repeated.RESULTS： Based on the BTLact results, SIBO was present in about 56% of IBS patients, and it was responsible for some IBS-related symptoms, such as abdominal bloating and discomfort, and diarrhoea. 1-wk treatment with Rifaximin turned the BTLact to negative in about 50% of patients and significantly reduced the symptoms, especially in those patients with an alternated constipation/diarrhoea-variant IBS. CONCLUSION： SIBO should be always suspected in patients with IBS, and a differential diagnosis is done by means of a ＂breath test＂. Rifaximin may represent a valid approach to the treatment of SIBO.

关键词： Rifaximin Small intestinal bacterialovergrowth Irritable bowel syndrome Locally nonabsorbable antibiotics

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Confirmatory factor analysis of VISA-P scale and measurement invariance across sexes in athletes with patellar tendinopathy

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Journal of Sport and Health Science 2017年第3期6卷 365-371页

作者： sergio Hernandez-Sanchez Ferran Abat María D.Hidalgo antonio I.Cuesta-Vargas Victor Segarra Jose M.Sanchez-Ibanez Antonia Gomez-Conesa Department of Pathology and Surgery Physiotherapy AreaMiguel Hernandez UniversityValencia 03550Spain Sports Orthopaedic Surgeon ReSport ClinicBarcelona 08017Spain Department of Basic Psychology and Methodology University of MurciaMurcia 30100Spain Department of Physiotherapy Faculty of Health SciencesUniversity of MalagaMalaga 29009Spain

Background:The Victorian Institute of Sport Assessment–Patella(VISA-P) scale is the most condition-specific patient-reported outcome measure used to assess symptom severity in athletes with patellar *** exploratory factor analyses have been conducted to evaluate the scale's dimensionality,with inconsistent results,and the factor structure of the scale remains *** aims of the present study were to determine the factorial structure of the VISA-P scale using confirmatory factor analysis(CFA) and test measurement invariance across ***:The study included a convenience sample of 249 Spanish athletes with patellar *** was performed to assess factorial *** 1-and 2-factor models were *** invariance across sexes was evaluated via multi-group CFA with several fit indices using EQS 6.1 ***:The internal consistency coefficient was *** CFA models were examined and the 1-factor model in which errors for Items 7 and8 were correlated showed acceptable fit in terms of comparative fit index(CFI) and goodness-of-fit index(GFI) statistics(CFI = 0.93;GFI = 0.94;standardized root mean square residual = 0.06;root mean square error of approximation = 0.10;90% confidence interval:0.08–0.13).This model was invariant across ***:The 1-factor model of the Spanish version of the VISA-P scale(VISA-P-Sp) in which errors for Items 7 and 8 were correlated demonstrated relative fit in *** obtained via VISA-P-Sp can be compared between men and women without sexes *** studies should examine the VISA-P scale and other single-score patient-reported outcome measures concurrently.

关键词： Jumper's knee Measurement invariance Patient-reported outcome measure Structural validity

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Estimation of Natural Gas Production,Import and Consumption in Brazil Based on Three Mathematical Models

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Natural Resources 2012年第2期3卷 42-47页

作者： antonio Carlos Gracias sergio Ricardo Lourenco Marat Rafikov Engineering Modeling and Applied Social Sciences Center(CECS)Federal University of ABCSanto AndreBrazil Department of Mathematics University Center of FEISao Bernardo do CampoBrazil

A mathematical model capable of providing a forecast of future consumption and import of natural gas is essential for the planning of the Brazilian energy matrix. The aim of this study is to compare three mathematical models, logistic model or model of Verhulst, exponential model or the model of Malthus and the model of von Bertalanffy to analyze the possibilities of these models to describe the evolution of production, import and consumption of natural gas in Brazil, from data provided by the energy balance of the Ministry of Mines and Energy (MME) from 1970 to 2009. A projection of the production and the import of natural gas up to 2017 is made with the models studied in this article and compared with the Brazilian Ten-Year Plan for Expansion of Energy (PDE). At the end of this paper a comparison with the Hubbert model for Brazilian natural gas production is made. These data were adjusted to use the differential equations which describe the models of population growth. All the computer work used in this article: graphics, resolution of differential equations, calculations of linearization and the least squares fitting was prepared in the software MatLab. The results obtained by means of graphs show that the population dynamics models (logistic, exponential and von Bertalanffy) can be applied in modeling the production, import and consumption of natural gas in Brazil.

关键词： Natural Gas Mathematical Modeling Logistic Model Exponential Model Model of Von Bertalanffy

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Alpha2-adrenergic receptor activation reinstates motor deficits in rats recovering from cortical injury

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Neural Regeneration Research 2023年第4期18卷 875-880页

作者： Gabriela García-Díaz Laura ERamos-Languren Carmen Parra-Cid Joel Lomelí sergio Montes Camilo Ríos antonio Bueno-Nava Ignacio Valencia-Hernández Rigoberto González-Piña Department of Pharmacology Section of Postgraduate Studies and ResearchHigh Medical SchoolInstituto Politécnico NacionalSalvador Díaz MirónAlcaldía Miguel HidalgoMexico CityMexico Department of Neurobiology of Aging and Brain Damage Coordination of Psychobiology and NeurosciencesFaculty of PsychologyNational Autonomous University of MexicoAv.Universidad 3040Col.Copilco UniversidadAlcaldía CoyoacánMexico CityMexico Direction of Research National Institute of Rehabilitation LGIICalz.Mexico-Xochimilco 289Col.Arenal de GuadalupeAlcaldía TlalpanMexico CityMexico Department of Pharmacology Multidisciplinary Academic Unit Reynosa-Aztlan ReynosaAutonomous University of Tamaulipascalle 16 y lago de ChapalaCol.AztlánTamaulipasMexico Department of Neurochemistry National Institute of Neurology and Neurosurgery MVSAv.Insurgentes Sur 3877Col.La FamaAlcaldia TlalpanMexico CityMexico Department of Special Education University of the AmericasPuebla 223Col.RomaAlcaldía CuauhtémocMexico CityMexico

Norepinephrine plays an important role in motor functional recovery after a brain injury caused by ferrous *** of norepinephrine release by clonidine is correlated with motor deficits after motor cortex *** aim of this study was to analyze the role ofα-adrenergic receptors in the restoration of motor deficits in recovering rats after brain *** rats were randomly assigned to the sham and injury groups and then treated with the following pharmacological agents at 3 hours before and 8 hours,3 days,and 20 days after ferrous chloride-induced cortical injury:saline,clonidine,efaroxan(a selective antagonist ofα-adrenergic receptors)and clonidine+*** sensorimotor score,the immunohistochemical staining forα-adrenergic receptors,and norepinephrine levels were *** hours post-injury,the sensorimotor score and norepinephrine levels in the locus coeruleus of the injured rats decreased,and these effects were maintained 3 days ***,20 days later,clonidine administration diminished norepinephrine levels in the pons compared with the sham *** effect was accompanied by sensorimotor *** effects were blocked by *** conclusion,an increase inα-adrenergic receptor levels was observed after *** restores motor deficits in rats recovering from cortical injury,an effect that was prevented by *** underlying mechanisms involve the stimulation of hypersensitiveα-adrenergic receptors and inhibition of norepinephrine activity in the locus *** results of this study suggest thatαreceptor agonists might restore deficits or impede rehabilitation in patients with brain injury,and therefore pharmacological therapies need to be prescribed cautiously to these patients.

关键词： alpha2-adrenoceptors ambulatory behavior clonidine cortical injury efaroxan functional recovery immunohistochemistry motor deficit norepinephrine sensorimotor score

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In silico Analysis of the Entire P. glaucum Genome Identifies Regulatory Genes of the bZIP Family Modulated in Response Pathways to Water Stress

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American Journal of Plant Sciences 2022年第2期13卷 277-293页

作者： Laura Beatriz Garay Farías sergio Litwiniuk Cristian antonio Rojas Federal University of Latin American Integration (UNILA) Foz do Igua&#962 u Brazil National Council for Scientific and Technical Research of Argentina Posadas Argentina

The literature reviewed places P. glaucum as a cereal characterized by its nutritional quality and high tolerance to drought stress. However, very little is known about the fine mechanism it uses in response to water stress. To try to clarify this point, we carried out an analysis of the modulation of the expression of regulatory genes of the FT bZIP family. A full genome screening of P. glaucum identified 52 putative FT bZIPs, identifying 9 FT PgbZIP differentially expressed under water stress conditions filtered from RNA-seq data from a Transcriptome deposited at the NCBI. The promoter regions of these genes presented multiple elements or cis ABREs and DRE motifs, thus suggesting their double modulated participation in the slow or adaptive response and in the rapid response of this cereal to water stress. The findings of this study provide complementary data for the understanding of the mechanism behind the adaptation of P. glaucum under water stress, and may be relevant for molecular applications of potential crops.

关键词： P. glaucum Water Stress RNA-seq cis Elements FT PgBZIP

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