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1.
Psychol Med ; 45(14): 3059-73, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26027740

RESUMO

BACKGROUND: Impaired emotion regulation may underlie exaggerated emotional reactivity in patients with obsessive compulsive disorder (OCD), yet instructed emotion regulation has never been studied in the disorder. METHOD: This study aimed to assess the neural correlates of emotion processing and regulation in 43 medication-free OCD patients and 38 matched healthy controls, and additionally test if these can be modulated by stimulatory (patients) and inhibitory (controls) repetitive transcranial magnetic stimulation (rTMS) over the left dorsolateral prefrontal cortex (dlPFC). Participants performed an emotion regulation task during functional magnetic resonance imaging before and after a single session of randomly assigned real or sham rTMS. Effect of group and rTMS were assessed on self-reported distress ratings and brain activity in frontal-limbic regions of interest. RESULTS: Patients had higher distress ratings than controls during emotion provocation, but similar rates of distress reduction after voluntary emotion regulation. OCD patients compared with controls showed altered amygdala responsiveness during symptom provocation and diminished left dlPFC activity and frontal-amygdala connectivity during emotion regulation. Real v. sham dlPFC stimulation differentially modulated frontal-amygdala connectivity during emotion regulation in OCD patients. CONCLUSIONS: We propose that the increased emotional reactivity in OCD may be due to a deficit in emotion regulation caused by a failure of cognitive control exerted by the dorsal frontal cortex. Modulatory rTMS over the left dlPFC may influence automatic emotion regulation capabilities by influencing frontal-limbic connectivity.


Assuntos
Tonsila do Cerebelo/fisiopatologia , Emoções , Transtorno Obsessivo-Compulsivo/terapia , Córtex Pré-Frontal/fisiopatologia , Estimulação Magnética Transcraniana , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Países Baixos , Testes Neuropsicológicos , Escalas de Graduação Psiquiátrica , Autorrelato
2.
J Anal Methods Chem ; 2014: 863019, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24782943

RESUMO

Application of headspace solid-phase microextraction (HS-SPME) coupled with high-resolution gas chromatographic (HRGC) analysis was studied for determining lactones in wines. Six different SPME fibers were tested, and the influence of different factors such as temperature and time of desorption, ionic strength, time of extraction, content of sugar, ethanol, tannins and anthocyanins, and pH and influence of SO2 were studied. The proposed HS-SPME-GC method is an appropriate technique for the quantitative analysis of γ-butyrolactone, γ-hexalactone, trans-whiskey lactone, γ-octalactone, cis-whiskey lactone, γ-nonalactone, γ-decalactone, δ-decalactone, and γ-undecalactone in wines. Method reproducibility and repeatability ranged between 0.6 and 5.2% for all compounds. Detection limit for γ-butyrolactone was 0.17 mg/L and a few µg/L for the rest of the compounds. The optimized method has been applied to several wine samples.

3.
Mar Pollut Bull ; 79(1-2): 107-13, 2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-24398419

RESUMO

Alcohol sulfates (AS) and alcohol ethoxysulfates (AES) are all High Production Volume and 'down-the-drain' chemicals used globally in detergent and personal care products, resulting in low levels ultimately released to the environment via wastewater treatment plant effluents. They have a strong affinity for sorption to sediments. Almost 50% of Tenerife Island surface area is environmentally protected. Therefore, determination of concentration levels of AS/AES in marine sediments near wastewater discharge points along the coast of the Island is of interest. These data were obtained after pressurized liquid extraction and liquid chromatography-tandem mass spectrometry analysis. Short chains of AES and especially of AS dominated the homologue distribution for AES. The Principal Components Analysis was used. The results showed that the sources of AS and AES were the same and that both compounds exhibit similar behavior. Three different patterns in the distribution for homologues and ethoxymers were found.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/química , Sulfatos/análise , Águas Residuárias/química , Poluentes Químicos da Água/análise , Espanha , Eliminação de Resíduos Líquidos , Águas Residuárias/estatística & dados numéricos
4.
Chemosphere ; 84(7): 869-81, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21723584

RESUMO

A multiresidue method for the analysis of 86 persistent pollutants in marine sediments at ultra-trace level has been developed and validated using pressurized liquid extraction (PLE) and stir-bar sorptive extraction (SBSE) coupled with thermal desorption and gas chromatography-triple quadrupole mass spectrometry (TD-GC-MS/MS QqQ). The compounds analyzed belong to various families such as polychlorinated biphenyls, polycyclic aromatic hydrocarbons, polybrominated diphenylethers, organophosphorus and organochlorine pesticides and other pesticides such as urons, and triazines. The analytes have very different polarities and log K(ow) values, which is an important parameter in the optimization of a SBSE method. Due to PLE high efficiency and throughput rates, along with the proven ability for multiresidue analysis and excellent sensitivity of SBSE, we present an efficient method. The limits of quantification obtained ranged from 0.014 to 1.0 ng g(-1), with detection limits below pg g(-1) levels. In order to validate the proposed methodology, quality parameters such as recovery, linearity and reproducibility were studied. Recoveries ranged from 63% to 119%, reproducibility (in terms of Relative Standard Deviation for ten determinations) was lower than 35% in all cases, and determination coefficients higher than 0.990 for all analytes. The main factors that affect PLE, SBSE and GC-MS/MS procedures were optimized. The method was applied to the analysis of nine marine sediments obtained from the nine main submarine wastewater discharge points (emissaries) presents along the coast of Tenerife Island (Canary Islands, Spain).


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Sedimentos Geológicos/química , Água do Mar/química , Poluentes Químicos da Água/análise , Adsorção , Fracionamento Químico , Dimetilpolisiloxanos/química , Monitoramento Ambiental/instrumentação , Monitoramento Ambiental/métodos , Espectrometria de Massas em Tandem , Poluentes Químicos da Água/química
5.
J Chromatogr A ; 1007(1-2): 127-35, 2003 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-12924558

RESUMO

A procedure based on solid-phase microextraction (SPME) and gas chromatography-mass spectrometry, operating in the chemical ionisation mode, was developed and optimised in order to determine 10 triazines in water samples. Five different SPME fibers available for analysis [polydimethylsiloxane (PDMS) 100 microm, polyacrylate (PA) 80 microm, PDMS-divinylbenzene (DVB) 65 microm, Carbowax (CW)-DVB 65 microm, and Carboxen (CAR)-PDMS 75 microm] were tested, and PDMS-DVB was selected. To enhance the sensitivity of the SPME, variables affecting adsorption and desorption steps such as temperature, time, pH and ionic strength of the solution were optimised. Detection limits obtained were ranged between 2 and 17 ng l(-1), and precision values were below 8% for the selected PDMS-DVB fiber. The optimised method was applied to real water samples and no triazines were detected.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Herbicidas/análise , Triazinas , Concentração de Íons de Hidrogênio , Concentração Osmolar , Sensibilidade e Especificidade
6.
Food Addit Contam ; 20(3): 237-40, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12623647

RESUMO

The concentrations of selenium and mercury were determined by atomic absorption spectrophotometry in sweet and dry bottled wines from the Canary Islands, Spain. The concentrations of mercury ranged from 2.6 to 4.9 microg x l(-1) for sweet wines, and from 1.5 to 2.6 microg x l(-1) for dry wines, differences (p < 0.05) being observed according to the island of production and type of wine, but not with respect to vintage. The concentration of selenium varied between 1.0 and 2.0 microg x l(-1) for sweet wines, and between 0.6 and 1.6 microg x l(-1) for dry wines. Differences were found in the mean concentrations according to the type of wine. Dry wines produced in La Palma presented a higher (p < 0.05) mean content than those observed in the wines of El Hierro and Lanzarote.


Assuntos
Contaminação de Alimentos/análise , Mercúrio/análise , Selênio/análise , Vinho/análise , Análise de Alimentos/métodos , Espanha , Espectrofotometria Atômica
7.
Food Addit Contam ; 20(2): 141-8, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12623662

RESUMO

Because of their high toxicity, arsenic, lead and cadmium need to be quantified in food and beverages. For the first time, in this study the content of arsenic, lead and cadmium was investigated in 152 wine samples from the Canary Islands, Spain, belonging to eight Denominations of Origin (DO) and four islands by inductively coupled plasma mass spectrometry (ICP-MS). The ranges of concentration found were 0.58-8.45 microg l(-1) for arsenic, 0.20-1.73 microg l(-1) for cadmium and 3.89-159.5 microg l(-1) for lead, and the mean content was 3.13, 0.63 and 28.74 microg l(-1), respectively. None of the wines contained levels above the limits set by the International Office of Vine and Wine (OIV), and thus did not pose a health hazard. Significant differences in mean content of those elements between harvest, type of wine, islands and DO were observed.


Assuntos
Arsênio/análise , Cádmio/análise , Contaminação de Alimentos , Chumbo/análise , Vinho/análise , Manipulação de Alimentos/métodos , Tecnologia de Alimentos , Espectrometria de Massas/métodos , Espanha
8.
J Chromatogr A ; 963(1-2): 213-23, 2002 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-12187973

RESUMO

Headspace solid-phase microextraction (HS-SPME) was studied for the high-resolution gas chromatographic (HRGC) analysis of esters in wines. Five different SPME fibers were tested and the influence of different factors such as temperature and time of desorption, extraction time, extraction technique, stirring, sample and vial volume, sugar and ethanol content were studied and optimised using model solutions. The proposed HS-SPME-GC method is an appropriate technique for the quantitative analysis of esters in dry and sweet white wines.


Assuntos
Cromatografia Gasosa/métodos , Ésteres/análise , Vinho/análise , Calibragem , Carboidratos/análise , Etanol/análise
9.
J Chromatogr A ; 963(1-2): 95-105, 2002 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-12188006

RESUMO

A solid-phase microextraction (SPME) procedure using three commercialised fibers (Carbowax-divinylbenzene, Carboxen-polydimethylsiloxane and divinylbenzene-Carboxen-polydimethylsiloxane) is presented for the determination of a selected group of organochlorine compounds in water samples. The extraction performances of these compounds were compared using fibers with two and three coatings. The optimal experimental procedures for the adsorption and desorption of pesticides were determined. The limits of detection with the divinylbenzene-Carboxen-polydimethylsiloxane fiber at levels below ng l(-1) were similar or lower than values presented in the literature for several of these compounds using polydimethylsiloxane fiber. The advantages of using this fiber, such as no salt addition, are discussed. Finally, the optimised procedures were applied successfully for the determination of these compounds in polluted ground water samples.


Assuntos
Hidrocarbonetos Clorados , Inseticidas/análise , Poluentes Químicos da Água/análise
10.
Plant Dis ; 81(8): 880-884, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30866374

RESUMO

Firm-breaker peaches (Prunus persica cv. Paraguayo), treated with 0.25 g liter-1 iprodione, were inoculated with 106 spores per ml of Alternaria tenuis and stored for up to 3 weeks at 0.5°C. Three intermittent warming (IW) cycles of 1 day at 20°C every 6 days at 0.5°C and modified atmosphere packaging (MAP) were applied. Fungicide treatment was ineffective in controlling growth of A. tenuis and Cladosporium spp. during storage. MAP prevented the growth of both fungal genera. IW alone or combined with fungicide seemed to increase total CFU counts and did not control decay (mainly due to exacerbated Cladosporium spp. development). CFU counts and losses through fungal attack were only occasionally significantly correlated.

11.
Plant Dis ; 81(8): 958, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30866392

RESUMO

Two Acremonium spp., A. tubakii and A. rutilum, were isolated from rotted peaches (Prunus persica (L.) Batsch 'Miraflores') after ripening at 15 and 20°C, respectively, for 10 days. Fruit harvested in September 1994 in Mula (Murcia) at a firm-ripe stage of maturity were either nontreated or washed with water at 18°C and sorted in a packing line. Sorted fruit were treated with an aqueous dilution of iprodione (Rovral 50% WP Rhône-Poulenc Agrochimie, Paris, France) at 2 g·liter-1, pH = 7, and 18°C for 5 min. Half of the iprodione-treated fruit were forced-air pre-cooled to reach 0°C at the endosperm in about 12 h. Isolations of fungi were made from subepidermic tissue of decay margins of fruit with potato dextrose agar (PDA). Fungal species were identified after axenic cultures were grown on PDA for 10 days at 30°C. Acremonium spp. were identified based on microscopic morphology of asexual reproduction structures, using taxonomic keys. No other fungi were isolated from fruit decayed by Acremonium spp. A. tubakii decayed 1.7% of the iprodionetreated and pre-cooled fruit ripened at 15 or 20°C and the fruit treated by iprodione without pre-cooling but ripened at 20°C. These fruit were completely decomposed and oozed liquid. Colonies of this species were light colored, with nonramified, nonseptate, and hyaline conidiophores. The one-cell, ovate, and hyaline conidia of the fungus were enclosed in slimy heads. A. tubakii did not cause any brown discoloration of the PDA media. A. rutilum affected 3.2% of the iprodione-treated fruit ripened at 20°C. In contrast to A. tubakii infection, A. rutilum affected only the surface of fruit, which remained dry. Cultures of A. rutilum were white to pink and the conidia were one-celled, ovate, and hyaline, forming a head on the tip of the nonramified conidiophores. Conidia were long, nonseptate, and distinct from the somatic hyphae. Acremonium spp. probably developed on injuries caused by handling and/or treatments, because these rots did not occur on untreated fruit. Rhizopus nigricans, and to a lesser extent other fungi such as Alternaria, Cladosporium, and Penicillium spp., also commonly caused decay of sampled fruit. A. tubakii is a ubiquitous soil fungus reported from various European countries. A. rutilum isolated from diseased apples were pathogenic upon reinoculation (1). Both fungi were not found in the Spanish type culture collection of 1990. Other Acremonium spp. have been identified in melon roots in Spain (2). To the best of our knowledge, this is the first report of Acremonium spp. causing decay of peach in Spain. References: (1) C. Brooks et al. Phytopathology 4:403, 1914. (2) J. García-Jiménez et al. Plant Dis. 78:416, 1994.

12.
Coyunt Econ ; 23(1): 111-37, 1993 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-12345426

RESUMO

PIP: The authors analyze departmental data for Colombia, with the aim of determining three things: whether there has been a postwar tendency toward convergence in the income of inhabitants of different departments; the fundamental determinants of interdepartmental migration; and the role of migratory flows from the perspective of convergence among departments.^ieng


Assuntos
Geografia , Renda , Dinâmica Populacional , Fatores Socioeconômicos , América , Colômbia , Demografia , Países em Desenvolvimento , Economia , Emigração e Imigração , América Latina , População , Pesquisa , América do Sul
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