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1.
Food Chem ; 372: 131263, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34818730

RESUMO

A combination of FTIR- and NMR-based metabolomics approaches coupled to multivariate data analysis techniques was used for the first time to characterize and explore the metabolic changes along the ripening of two Spanish melon landraces (Jimbee N and Jimbee XL). Furthermore, the fatty acids profile and the antioxidant capacity were investigated by GC-FID and ORAC method, respectively. Despite FTIR was able to identify changes in the sugars content between fruits of different maturity stages, it failed to discriminate between both varieties, being exceeded by NMR in both situations. Increased fruit maturation led to an increase of sucrose, fatty acids and ß-carotene, accompanied by a decrease of glucose, fructose, citrate, amino acids, and polyphenols (which were positively correlated with fruits antioxidant activity).


Assuntos
Cucumis melo , Cucurbitaceae , Frutas , Espectroscopia de Ressonância Magnética , Metabolômica
2.
Sensors (Basel) ; 20(1)2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31906382

RESUMO

Greenhouse cultivation has gained a special importance in recent years and become the basis of the economy in south-eastern Spain. The structures used are light and, due to weather events, often collapse completely or partially, which has generated interest in the study of these unique buildings. This study presents a load and displacement monitoring system that was designed, and full scale tested, in an Almería-type greenhouse with a tensioned wire structure. The loads and displacements measured under real load conditions were recorded for multiple time periods. The traction force on the roof cables decreased up to 22% for a temperature increase of 30 °C, and the compression force decreased up to 16.1% on the columns or pillars for a temperature and wind speed increase of 25.8 °C and 1.9 m/s respectively. The results show that the structure is susceptible to daily temperature changes and, to a lesser extent, wind throughout the test. The monitoring system, which uses load cells to measure loads and machine vision techniques to measure displacements, is appropriate for use in different types of greenhouses.

3.
J Agric Food Chem ; 67(46): 12972-12985, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31709797

RESUMO

Controlling the temperature inside a greenhouse during the summer is a problem of increasing importance in the Mediterranean countries, especially in the Spanish southeast. The metabolic profile of greenhouse tomatoes and leaves grown under conventional conditions and within the presence of a shade mesh (∼50% reduction of sunlight radiation) has been monitored. Tomatoes were weekly harvested from May to July 2017 and analyzed by NMR spectroscopy coupled to multivariate data analysis techniques, together with oxygen radical absorbance capacity (ORAC) assays (for antioxidant activity). Fatty acids and carotenoids profiles were unraveled by GC-FID and HPLC-DAD, respectively. To verify whether it would be possible to take advantage of different light growing conditions to potentiate a plant's defense system, leaves of the corresponding plants were collected and their methanolic extracts were analyzed by NMR toward deciphering new biomarkers, which were used to assess their antibacterial and antibiofilm activities. The presence of a shading mesh resulted in a reduction in tomato production and in smaller fruits with lower contents of sugars (glucose and fructose) and carotenoids (lycopene and ß-carotene) and higher contents of organic acids, amino acids, and polyunsaturated fatty acids (linoleic and oleic acids) and of phenylpropanoids and flavonoids (which contributed to an increased antioxidant activity). Methanolic extracts of leaves of nonshaded plants showed a higher antibiofilm activity than that from shaded plants. This activity was well-correlated with an increase of phenolic compounds, together with some specific amino acids and organic acids from tomato leaves.


Assuntos
Frutas/química , Folhas de Planta/química , Solanum lycopersicum/efeitos da radiação , Antioxidantes/metabolismo , Alimentos Orgânicos/análise , Alimentos Orgânicos/efeitos da radiação , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Frutas/efeitos da radiação , Solanum lycopersicum/química , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/metabolismo , Espectroscopia de Ressonância Magnética , Metaboloma/efeitos da radiação , Metabolômica , Valor Nutritivo/efeitos da radiação , Extratos Vegetais/química , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Folhas de Planta/efeitos da radiação , Luz Solar
4.
J Agric Food Chem ; 66(31): 8422-8432, 2018 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-30047728

RESUMO

This study describes the approach of 1H NMR metabolomic profiling for the differentiation of zucchini produced under different conditions of water irrigation (desalinated seawater -0.397 dS/m, 0.52 €/m3 vs groundwater -2.36 dS/m, 0.29 €/m3) and ventilation (surface area of the vent openings/greenhouse area was 15.0% for one sector and 9.8% for the other). Overall, 72 extracts of zucchini ( Cucubirta pepo L. cv Victoria) under four different conditions were regularly analyzed during the spring-summer cycle from April to July 2017. We have found that zucchini plants irrigated with desalinated seawater increased the zucchini production yield, presented fruits with higher concentration of glucose, fructose, and vitamin B3, and displayed an increased antioxidant activity. On the contrary, plant groundwater irrigation produced the increment of sucrose level that could rise the sweetness perception of the fruits. Finally, the ventilation variable produced a higher concentration of trigonelline, histidine, and phenylalanine but only on those zucchinis irrigated with groundwater.


Assuntos
Agricultura/métodos , Cucurbita/crescimento & desenvolvimento , Espectroscopia de Ressonância Magnética/métodos , Metabolômica/métodos , Irrigação Agrícola/métodos , Agricultura/instrumentação , Antioxidantes/análise , Frutose/análise , Frutas/química , Frutas/crescimento & desenvolvimento , Glucose/análise , Água Subterrânea , Niacinamida/análise , Extratos Vegetais/química , Água do Mar , Ventilação , Água
5.
Sensors (Basel) ; 16(5)2016 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-27187401

RESUMO

The present work studies the effect of three insect-proof screens with different geometrical and aerodynamic characteristics on the air velocity and temperature inside a Mediterranean multi-span greenhouse with three roof vents and without crops, divided into two independent sectors. First, the insect-proof screens were characterised geometrically by analysing digital images and testing in a low velocity wind tunnel. The wind tunnel tests gave screen discharge coefficient values of Cd,φ of 0.207 for screen 1 (10 × 20 threads·cm(-2); porosity φ = 35.0%), 0.151 for screen 2 (13 × 30 threads·cm(-2); φ = 26.3%) and 0.325 for screen 3 (10 × 20 threads·cm(-2); porosity φ = 36.0%), at an air velocity of 0.25 m·s(-1). Secondly, when screens were installed in the greenhouse, we observed a statistical proportionality between the discharge coefficient at the openings and the air velocity ui measured in the centre of the greenhouse, ui = 0.856 Cd + 0.062 (R² = 0.68 and p-value = 0.012). The inside-outside temperature difference ΔTio diminishes when the inside velocity increases following the statistically significant relationship ΔTio = (-135.85 + 57.88/ui)(0.5) (R² = 0.85 and p-value = 0.0011). Different thread diameters and tension affects the screen thickness, and means that similar porosities may well be associated with very different aerodynamic characteristics. Screens must be characterised by a theoretical function Cd,φ = [(2eµ/Kpρ)·(1/us) + (2eY/Kp(0.5))](-0.5) that relates the discharge coefficient of the screen Cd,φ with the air velocity us. This relationship depends on the three parameters that define the aerodynamic behaviour of porous medium: permeability Kp, inertial factor Y and screen thickness e (and on air temperature that determine its density ρ and viscosity µ). However, for a determined temperature of air, the pressure drop-velocity relationship can be characterised only with two parameters: ΔP = aus² + bus.


Assuntos
Movimentos do Ar , Falha de Equipamento , Insetos , Animais , Produtos Agrícolas , Temperatura , Vento
6.
Sensors (Basel) ; 12(10): 13852-70, 2012 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-23202025

RESUMO

The present work has developed a methodology based on thermography and sonic anemometry for studying the microclimate in Mediterranean greenhouses equipped with air heaters and polyethylene distribution ducts to distribute the warm air. Sonic anemometry allows us to identify the airflow pattern generated by the heaters and to analyze the temperature distribution inside the greenhouse, while thermography provides accurate crop temperature data. Air distribution by means of perforated polyethylene ducts at ground level, widely used in Mediterranean-type greenhouses, can generate heterogeneous temperature distributions inside the greenhouse when the system is not correctly designed. The system analyzed in this work used a polyethylene duct with a row of hot air outlet holes (all of equal diameter) that expel warm air toward the ground to avoid plant damage. We have observed that this design (the most widely used in Almería's greenhouses) produces stagnation of hot air in the highest part of the structure, reducing the heating of the crop zone. Using 88 kW heating power (146.7 W ∙ m(-2)) the temperature inside the greenhouse is maintained 7.2 to 11.2 °C above the outside temperature. The crop temperature (17.6 to 19.9 °C) was maintained above the minimum recommended value of 10 °C.


Assuntos
Ar/análise , Ambiente Controlado , Calefação/instrumentação , Termografia , Agricultura/instrumentação , Agricultura/métodos , Cucurbita/fisiologia , Análise de Falha de Equipamento/métodos , Calefação/métodos , Umidade , Região do Mediterrâneo , Microclima , Temperatura , Termografia/instrumentação , Termografia/métodos
7.
Gac. sanit. (Barc., Ed. impr.) ; 19(6): 433-439, nov. 2005. tab
Artigo em En | IBECS | ID: ibc-044304

RESUMO

Objetivo: El cuestionario de salud SF-36 puede ser autoaplicado o utilizado en entrevistas personales o telefónicas. El objetivo principal de este trabajo fue comparar la aplicación telefónica del cuestionario y la versión autoaplicada en una población de Girona (España). Métodos: Diseño cruzado y aleatorizado para la aplicación de las dos formas del cuestionario. Se asignaron dos órdenes de aplicación de las encuestas (telefónica-autoaplicada y autoaplicada-telefónica). Un total de 261 personas completaron los cuestionarios. Las comparaciones entre modos de aplicación se realizaron mediante la prueba de la t de Student para datos apareados. La consistencia interna y la concordancia entre modos de aplicación se analizaron mediante los coeficientes * de Chronbach y de correlación intraclase, respectivamente. Su utilizó un modelo lineal general para medidas repetidas para evaluar el efecto del orden de la aplicación de los cuestionarios. Resultados: Cuando se utilizó primero el cuestionario autoaplicado, las escalas de función física, rol físico y función social resultaron en una menor puntuación. Todos los coeficientes * de Chronbach fueron superiores a 0,70, excepto para la escala de función social en la modalidad autoaplicada cuando se aplicó primero la encuesta telefónica. El rango de los coeficientes de correlación intraclase fue de 0,41 a 0,83 en la modalidad telefónica-autoaplicada y de 0,32 a 0,73 en la modalidad autoaplicada-telefónica. No se observó un efecto relevante del orden de aplicación. Conclusiones: Los resultados de este estudio indican que la aplicación de la encuesta telefónica es equivalente e tan válida como la encuesta autoaplicada


Objective: The characteristics of the 36 item Medical Outcome Short Form Health Study Survey (SF-36) questionnaire, designed as a generic indicator of health status for the general population, allow it to be self-administered or used in personal or telephone interviews. The main objective of the study was to compare the telephone and self-administered modes of SF-36 for a population from Girona (Spain). Methods: A randomized crossover administration of the questionnaire design was used in a cardiovascular risk factor survey. Of 385 people invited to participate in the survey, 351 agreed to do so and were randomly assigned to two orders of administration (i.e., telephone-self and self-telephone); 261 completed both questionnaires. Scores were compared between administration modes using a paired t test. Internal consistency and agreement between modalities were analyzed by respectively applying Chronbach's alpha and intraclass correlation coefficients. The effect of the order of administration on the test-retest difference was analyzed by one-way ANOVA for repeated measurements. Results: Physical function, physical role and social functioning received significantly lower scores when the self-administered questionnaire was used prior to the telephone survey. When the initial survey was conducted by telephone, all Chronbach's alpha coefficients (except social functioning) scored over 0.70 in the self-administered modality. The intraclass correlation coefficient ranged from 0.41 to 0.83 for the telephone-self order and from 0.32 to 0.73 for the self-telephone order. No clinically significant effect was observed for the order of application. Conclusions: The results of the present study suggest that the telephone-administration mode of SF-36 is equivalent to and as valid as the self-administered mode


Assuntos
Masculino , Feminino , Adulto , Idoso , Pessoa de Meia-Idade , Humanos , Inquéritos Epidemiológicos , Inquéritos e Questionários , Telefone , Estudos Cross-Over , Espanha
8.
Gac Sanit ; 19(6): 433-9, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16483520

RESUMO

OBJECTIVE: The characteristics of the 36 item Medical Outcome Short Form Health Study Survey (SF-36) questionnaire, designed as a generic indicator of health status for the general population, allow it to be self-administered or used in personal or telephone interviews. The main objective of the study was to compare the telephone and self-administered modes of SF-36 for a population from Girona (Spain). METHODS: A randomized crossover administration of the questionnaire design was used in a cardiovascular risk factor survey. Of 385 people invited to participate in the survey, 351 agreed to do so and were randomly assigned to two orders of administration (i.e., telephone-self and self-telephone); 261 completed both questionnaires. Scores were compared between administration modes using a paired t test. Internal consistency and agreement between modalities were analyzed by respectively applying Chronbach's alpha and intraclass correlation coefficients. The effect of the order of administration on the test-retest difference was analyzed by one-way ANOVA for repeated measurements. RESULTS: Physical function, physical role and social functioning received significantly lower scores when the self-administered questionnaire was used prior to the telephone survey. When the initial survey was conducted by telephone, all Chronbach's alpha coefficients (except social functioning) scored over 0.70 in the self-administered modality. The intraclass correlation coefficient ranged from 0.41 to 0.83 for the telephone-self order and from 0.32 to 0.73 for the self-telephone order. No clinically significant effect was observed for the order of application. CONCLUSIONS: The results of the present study suggest that the telephone-administration mode of SF-36 is equivalent to and as valid as the self-administered mode.


Assuntos
Inquéritos Epidemiológicos , Inquéritos e Questionários , Telefone , Adulto , Idoso , Estudos Cross-Over , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Espanha
9.
Eur J Epidemiol ; 19(3): 231-7, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15117116

RESUMO

BACKGROUND AND OBJECTIVES: The myocardial infarction (MI) incidence rate, prognosis and hospitalisation rate in the population 65 and over are rarely studied. We sought to determine MI hospitalisation and incidence rates, and 28-day case-fatality, in the 65 year and older population, and to analyse whether their management and prognosis differed from that of younger patients. METHODS: All residents in Gerona (Spain) older than 24 years with suspected fatal or non-fatal MI were investigated and included in a population registry. RESULTS: MI mortality, incidence, and case-fatality dramatically increased with age after 64. Smoking, thrombolysis, antiplatelet and betablocker drug use, coronary angiograms, and coronary revascularisation decreased with age. The risk of death of patients between 75 and 84 years (OR: 4.15, 95% confidence interval, CI: 1.70-10.15) and between 85 and 94 years (OR: 4.68, 95% CI: 1.62-13.52) was higher than in the 34-64 years age group, independently of any patient characteristic. CONCLUSIONS: The magnitude of the impact of MI in the elderly at population and hospital levels is substantially higher than in those younger than 65 years of age. After this age patients receive less treatments and procedures than their younger counterparts.


Assuntos
Pacientes Internados , Infarto do Miocárdio/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Pesquisa sobre Serviços de Saúde , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/mortalidade , Sistema de Registros , Fatores de Risco , Espanha/epidemiologia
10.
J Chromatogr A ; 999(1-2): 51-60, 2003 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-12885051

RESUMO

Trace determination (low ng/ml) of linear alkylbenzensulfonates (LASs) in water was achieved by solid-phase microextraction (SPME) of ion-pairs formed with tetrabutylammonium. This ion-pairing reagent served two purposes. First, it allowed the extraction of LAS with the polydimethylsiloxane fiber by counterion association and second, the derivatization of the formed LAS ion pairs in the GC injection port at 300 degrees C to form the corresponding sulfonated butyl esters. The methodology developed allows the isomer specific determination of LAS at low detection limits (0.16-0.8 ng/ml), depending on the alkyl chain lengths of LASs with RSDs of 10-12%. Furthermore, the developed methodology was applied to urban wastewater and sea water and compared with a solid-phase extraction (SPE) method (e.g. C18 and strong anion-exchange sorbent) to obtain concordant values for urban wastewater. Moreover, the developed SPME methodology overcame the procedural blank and matrix-dependent recoveries found in the SPE methodologies at low LAS concentrations.


Assuntos
Ácidos Alcanossulfônicos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Água/química , Cromatografia Líquida , Temperatura
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