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Amperometric Nitrous Oxide Gas Sensor： Preparation ol Cu/PANI/Cu Electrodes and Sensing Behavior

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Journal of Environmental Science and Engineering(B) 2012年第12期1卷 1297-1302页

作者： Luisa Quifiones-Montenegro Eduardo Herrera-Peraza Carmen Navarro B. Trujillo-Navarrete Yadira Gochi laura ortega Department of Environment and Energy Research Center for Advanced MaterialsMdxico Chihuahua 31000 Graduate Department Technological Institute of OaxacaMdxico Oaxaca 68000 Department of Basic Science Technological Institute of Chihuahua II. Chihuahua MexicoChihuahua 31000

The authors studied the changes in the electrical properties of PANI （polyaniline） when exposed to the presence of N20 （nitrous oxide）. The techniques used to determine the adsorption of gas in the polymer were the electrochemical impedance, steps voltammetry and transmission electron microscopy. The objective of this work was to determine the ability of adsorption and desorption of PANI to be used as sensor in an open environment. Measurements were performed in a controlled atmosphere, temperature and flux. The gas was passed through a glass capsule in which an electrochemical cell was designed with copper electrodes and PANI as electrolyte. The change in electrical properties of the material is analyzed using a potentiostat/galvanostat in situ. Subsequently, the material was analyzed by TEM （Transmission Electron Microscopy） elemental analysis. The measurements were performed with difl^rent concentrations of N20 with a purity of 99%. As a result of measurements, it was found that the change in electrical resistance of PANI is caused by the physical interaction that occurs when in contact with NzO and even a change in the morphology of polymer, however, the binding is weak and sufficient to increase the temperature at which 25% PANI film regains its original properties.

关键词： Polymer electrochemical gas sensor nitrous oxide impedance.

Prevalence of Mild T30, T3, and Severe VT Strains of Citrus tristeza Virus in Central-Northern Veracruz, Mexico

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American Journal of Plant Sciences 2022年第4期13卷 494-505页

作者： Rosalba Contreras-Maya Angel Villegas-Monter Amalio Santacruz-Varela Nicacio Cruz-Huerta laura D. ortega-Arenas Daniel L. Ochoa-Martinez Colegio de Postgraduados Texcoco Estado de México México

The presence and distribution of Citrus tristeza virus (CTV) strains on plants of four citrus species required analysis of plants showing small fruits, yellowing, and twig dieback. Typical citrus tristeza symptoms showed in citrus plantations in Veracruz, Mexico, and caused gradual deterioration, low yield, and death of the plants. Seven citrus-growing municipalities in Central and Northern Veracruz presented the severe VT strain: the incidence in seven of the eight sampled municipalities ranged from 7% in Alamo to 50% in Tihuatlan. As for the T30 strain, its presence and distribution ranged from 17% in Tihuatlan to 83% in Cuitlahuac. Values for the T3 strain went from 20% in Castillo de Teayo to 50% in Papantla. In Tihuatlan, two samples were positive for the T36 strain. Only Citrus sinensis has historical recording infections by severe strains of CTV, unlike other important citrus species. The incidence of orchards quickly declining increases rapidly in Veracruz, the largest citrus producer in Mexico. It becomes critical as the predominant and sensitive rootstock is sour orange (Citrus aurantium). It is important to note that the specific primers used could not be identified in 29% of the samples, suggesting that they could be other than T30, T3, VT, and T36 strains.

关键词： Citrus Incidence Strains Quick Decline Severity

Turning carbon dots into selenium bearing nanoplatforms with in vitro GPx-like activity and pro-oxidant activity

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Nano Research 2023年第5期16卷 7784-7791页

作者： laura Perez-Garrido Mariano ortega-Muñoz Fernando Hernandez-Mateo F.Javier Lopez-Jaramillo Francisco Santoyo-Gonzalez Department of Organic Chemistry Biotechnology InstituteSchool of SciencesCampus Fuentenueva snUniversity of Granada18071-GranadaSpain

Selenium(Se)has been defined as the“Janus element”,with one face showing antioxidant activity and the other pro-oxidant *** biological effect of Se depends on both dose and *** nanoparticles are attracting major interest,although their large-scale preparation for biomedical applications is not *** hypothesize that acid anhydride-coated carbon dots(AACD)are an attractive platform for preparing nanoparticles containing chemically defined *** reaction of AA-CD with 3-selenocyanatopropan-1-amine yields carbon dots bearing selenocyanate and carboxylate groups(CD-SeCN)that allow for tuning the ***-SeCN has a Se content of 0.36μmol per mg of nanoparticles,they show the typical photoluminescence of carbon *** selenocyanate groups(SeCN)exhibited glutathione peroxidase-like activity and *** show that antioxidant behavior differs between normal and tumor cells,the evaluation on HEK293 and A549 cells reveals that the toxicity of CD-SeCN depends on dose,time,intracellular glutathione(GSH)*** toxicity of CD-SeCN decreases with the time of incubation and the cell death mechanism switches from necrosis to apoptosis,indicating that CD-SeCN is ***,high levels of intracellular GSH exert a protective *** results support a pharmacological potential in cancers with low levels of intracellular *** use of AA-CD as nanoplatforms is a general strategy that paves the way for the engineering of advanced nanosystems.

关键词： selenium nanoparticles carbon dots glutathione peroxidase-like activity Janus element nanomedicine

Application of formal languages in polynomial transformations of instances between NP-complete problems

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第8期14卷 623-633页

作者： Jorge A. RUIZ-VANOYE Joaquín PREZ-ortega Rodolfo A. PAZOS RANGEL Ocotlán DíAZ-PARRA Héctor J. FRAIRE-HUACUJA Juan FRAUSTO-SOLíS Gerardo REYES-SALGADO laura CRUZ-REYES DACI Universidad Autónoma del Carmen Computer Science Centro Nacional de Investigación y Desarrollo Tecnológico Systems and Computer Science Instituto Tecnológico de Ciudad Madero Informatics Universidad Politécnica del Estado de Morelos Computer Science Instituto Tecnológico de Cuautla

We propose the usage of formal languages for expressing instances of NP-complete problems for their application in polynomial transformations. The proposed approach, which consists of using formal language theory for polynomial transformations, is more robust, more practical, and faster to apply to real problems than the theory of polynomial transformations. In this paper we propose a methodology for transforming instances between NP-complete problems, which differs from Garey and Johnson's. Unlike most transformations which are used for proving that a problem is NP-complete based on the NP-completeness of another problem, the proposed approach is intended for extrapolating some known characteristics, phenomena, or behaviors from a problem A to another problem B. This extrapolation could be useful for predicting the performance of an algorithm for solving B based on its known performance for problem A, or for taking an algorithm that solves A and adapting it to solve B.

关键词： Formal languages Polynomial transformations NP-completeness

Effectiveness of statins *** on reducing postprandial hypertriglyceridemia in dyslipidemic population:A systematic review and network meta-analysis

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Journal of Sport and Health Science 2022年第5期11卷 567-577页

作者： laura Alvarez-Jimenez Alfonso Moreno-Cabanas Miguel Ramirez-Jimenez Felix Morales-Palomo Juan Fortega Ricardo Mora-Rodriguez Exercise Physiology Lab at Toledo Sports Science DepartmentUniversity of Castilla-La ManchaToledo 45004Spain

Background:Individuals at risk of suffering cardiovascular disease(CVD) present with larger increases in blood trigyceride(TG) concentration after a high-fat meal than do healthy *** postprandial hypertriglyceride levels are an independent risk factor for *** of statins and a bout of prolonged exercise are both effective in lowering postprandial hypertriglyceride *** aimed to evaluate the comparative effectiveness of statins vs.a bout of aerobic exercise in reducing fasting and postprandial TG(PPTG) concentrations in indiv、duals at high nsk of developing ***:Thirty-seven sltudies from a systematic literature search of the PubMed,EMBASE,and Cochrane databases were included in this *** selected studies conducted trials involving statin therapy(n=20) or a bout of aerobic exercise(n=19) and measured their impact on PPTG levels as the *** studies analyzed both treatments and were included in *** meta-analysis was constructed using a random-effects model to calculate the mean difference(MD).The Student t test was used to compare the data sets for statins ***:Overall,statin and exercise interventions showed similar reductions in PPTG levels,with an MD of-0.65 mmol/L for statins(95% confidence interval(95%CI):-0.54 to-0.77;p <0.001) and-0.46 mmol/L for exercise(95%CI:-0.21 to-0.71;p <0.01).However,statins lowered fasting TG levels more than exercise(MD=-1.54 mmol/L,95%CI:-2.25 to-0.83;p=0.009).Conclusion:Although aerobic exercise is effective in lowering blood TG levels,statins seem to be more efficient,especially in the fasted state.A combination of exercise and statins might reveal a valuable approach to the treatment and prevention of *** studies are required to determine the underlying mechanisms and the possible additive effects of these interventions.

关键词： Aerobic exercise Cardiovascular disease Hydroxymethylglutaryl-CoA reductase inhibitor Meta-analysis Metabolic syndrome

Longitudinal bending stiffness does not affect running economy in Nike Vaporfly Shoes

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Journal of Sport and Health Science 2022年第3期11卷 285-292页

作者： laura A.Healey Wouter Hoogkamer Integrative Locomotion Laboratory Department of KinesiologyUniversity of MassachusettsAmherstMA 01003-9258USA

Purpose This study aimed to determine the independent effect of the curved carbon-fiber plate in the Nike Vaporfly 4%shoe on running economy and running *** Fifteen healthy male runners completed a metabolic protocol and a biomechanics *** both protocols participants wore 2 different shoes,an intact Nike Vaporfly 4%(VF_(intact))and a cut Nike Vaporfly 4%(VF_(cut)).The VF_(cut) had 6 medio-lateral cuts through the carbon-fiber plate in the forefoot to reduce the effectiveness of the *** the metabolic protocol,participants ran at 14 km/h for 5 min,twice with each shoe,on a force-measuring treadmill while we measured metabolic *** the biomechanics protocol,participants ran across a runway with embedded force plates at 14 km/*** calculated running economy,kinetics,and lower limb joint *** Running economy did not significantly differ between shoe conditions(on average,0.55%±1.77%(mean±SD))worse in the VF_(cut) compared to the VF_(intact);95%confidence interval(-1.44%to 0.40%).Biomechanical differences were only found in the metatarsophalangeal(MTP)joint with increased MTP dorsiflexion angle,angular velocity,and negative power in the VF_(cut).Contact time was 1%longer in the VF_(intact).Conclusion Cutting the carbon-fiber plate and reducing the longitudinal bending stiffness did not have a significant effect on the energy savings in the Nike Vaporfly 4%.This suggests that the plate's stiffening effect on the MTP joint plays a limited role in the reported energy savings,and instead savings are likely from a combination and interaction of the foam,geometry,and plate.

关键词： Biomechanics Footwear Mechanical doping Metabolic rate Performance

Anti-inflammatory Activity and Antioxidant Potential of Aqueous Extracts from Stem Bark of Geoffroea decorticans

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Journal of Pharmacy and Pharmacology 2017年第10期5卷 703-707页

作者： Maria Jofre Maria Fusco laura Favier Mauricio Teves Alejandra Rotelli Lilian Pelzer Claudia ortega Diego Cifuente Area de Farmacognosia-Farmacologla Universidad Nacional de San Luis San Luis 5700 Argentina Area de Qulmica Organica Universidad Nacional de San Luis San Luis 5700 Argentina

In the present work we investigated, for the first time, the anti-inflammatory activity and the antioxidant properties of aqueous and ethanolic extracts, obtained from stem bark of Geoffroea decorticans （Gill. ex Hook. et Am.） Burk. （Fabaceae）. G. decorticans, commonly known as ＂chafiar＂ or ＂chafiarcillo＂, is a traditional argentinean plant used as emollient, balsamic, antitussive, expectorant and anti-inflammatory. The stem bark was collected from San Francisco del Monte de Oro, San Luis, Argentina. Anti-inflammatory activity was evaluated by carrageenan-induced paw edema in rats. Antioxidant activity was tested using 1,1-Diphenyl-2-picrylhydrazyl radical-scavenging activity （DPPH）, 2,2＂-Azino-bis（3-ethylbenzthiazoline-6-sulphonic acid） radical scavenging activity （ABTS） and ferric ion-reducing power （RP-Fe） assays. Aqueous extract 10% p/v showed anti-inflammatory activity （3h, 48% inhibition, 5h 37% inhibition and 7h 17% inhibition） and antioxidant activity （DPPH, ICs0 （mg/mL） = 0.098 =1： 0.032; ABTS, ICs0 （mg/mL） = 0.022 ~ 0.343, RP-Fe IC50 （mg/mL） = 1.124 ~ 0.146）. In the other hand, the ethanolic extract 5% p/v, presented anti-inflammatory activity （3h, 34% inhibition, 5h 38% inhibition and 7h 35% inhibition） and antioxidant activity （DPPH, IC50 （mg/mL） = 0.133 q- 0.027; ABTS, IC50 （mg/mL） = 0.086 ＋ 0.262, RP-Fe IC50 （mg/mL） = 7.089 ± 0.104）. These results suggest that, also fruits, the aqueous and ethanolic extracts from the stem bark of G. decorticans present significant anti-inflammatory activity and antioxidant properties.

关键词： Anti-inflammatory bioactivity antioxidant properties Geoffroea decorticans.

Effect of Nanoparticles on Mechanical Properties of Cement-Sand Mortar Applications

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Advances in Chemical Engineering and Science 2017年第3期7卷 270-276页

作者： José Salvador Cavazos Gustavo González Oxana V. Kharissova Beatriz ortega laura Peñ a Mario Osorio Mauricio Garza-Castañ ón Universidad de Monterrey Physics and Mathematics Department Engineering and Technologies Division San Pedro Garza-García N.L.México Universidad Autónoma de Nuevo León Facultad de Ciencias Físico-Matemáticas Pedro de Alba S/N Ciudad Universitaria San Nicolás de los Garza N.L. Mexico

Cement-sand mortar is a construction material widely used;tile adhesive is one of the main applications where the compressive strength is the key performance metric. Nanoparticles like MWCNTs and HNTs are currently being used to improve the mechanical performance of the cement mortar due to their properties. The cost of MWCNTs has limited their application in the construction industry. This study focuses on the effect of two different concentrations of MWCNTs and HNTs in cement mortar;HNTs are proposed in this study to compare performance and cost overall benefits. A common problem with MWCNTs is agglomeration;to achieve a proper dispersion an ultrasonic processor was utilized. Mechanical properties of a cement mortar modified with nanoparticles were investigated with compression and bending tests on specimens performed at the age of 7 days. Results showed that concentrations of 0.1% of MWCNTs increase in compression strength by 56% and concentrations of 0.1% of HNTs performance increased by 31%, both compared to plain cement mortar.

关键词： Mechanical Properties Compressive Strength Cement Cement Manufacture

Inhaler Technique Questionnaire(InTeQ)in pediatric patients with asthma

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World Journal of Pediatrics 2023年第8期19卷 798-804页

作者： Catalina Lizano‑Barrantes Olatz Garin Alexandra Lelia Dima Karina Mayoral Angels Pont Eva María Ortiz María Araceli Caballero‑Rabasco Manuel Praena‑Crespo laura Valdesoiro‑Navarrete María Teresa Guerra Alberto Bercedo‑Sanz Gimena Hernández Camila Maroni Inés de Mir MaríaÁngeles Carrasco Marta ortega Alberto Servan JoséAntonio Castillo Eva Tato Montse Ferrer Health Services Research Group IMIM(Hospital del Mar Medical Research Institute)Barcelona Biomedical Research ParkDoctor Aiguader8808003 BarcelonaSpain Department of Medicine and Life Sciences Universitat Pompeu FabraBarcelonaSpain Department of Pharmaceutical Care and Clinical Pharmacy Faculty of PharmacyUniversidad de Costa RicaSan JoseCosta Rica Centro de Investigación Biomédica en Red de Epidemiología y Salud Pública CIBERESP MadridSpain Research and Development Unit Institut de Recerca Sant Joan de DéuBarcelonaSpain Department of Pediatrics Obstetrics and Gynaecology and Preventive MedicineUniversitat Autònoma de BarcelonaBarcelonaSpain Pediatric Allergy and Pulmonology Unit Pediatric ServiceHospital del MarBarcelonaSpain Pediatric Allergy and Pulmonology Unit Pediatric ServiceHospital Universitari Parc TaulíSabadellSpain Centro de Salud La Candelaria Servicio Andaluz de SaludSevilleSpain Grupo de Vías Respiratorias de La Asociación Española de Pediatras de Atención Primaria(AEPAP) MadridSpain Centro de Salud Jerez Sur Servicio Andaluz de SaludSevilleSpain Centro de Salud La Sagrera BarcelonaSpain Centro de Salud Los Castros CantabriaSpain Facultat de Medicina Universitat Autònoma de BarcelonaBarcelonaSpain Pediatric Allergy and Pulmonology and Cystic Fibrosis UnitHospital Universitari Vall d’HebronBarcelonaSpain Consultorio Sevilla la Nueva MadridSpain Centro de Salud Dos de Mayo MadridSpain Hospital Miguel Servet ZaragozaSpain Hospital Universitario Araba Vitoria-GasteizSpain Departamento de Farmacologia Pediatría y RadiologíaUniversidad de SevillaSevilleSpain Institut d’Investigaciói InnovacióParc Taulí SabadellSpain

Asthma in school-aged children is a major public health problem worldwide[1,2].Inhaled medications are the mainstay of its pharmacological management[2],but only 8%-22%of children with asthma use their inhalers correc... 详细信息

关键词： asthma pediatric patients