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1.
Rev Chil Pediatr ; 86(3): 173-81, 2015.
Artículo en Español | MEDLINE | ID: mdl-26363858

RESUMEN

INTRODUCTION: The high flow nasal cannula (HFNC) is a method of respiratory support that is increasingly being used in paediatrics due to its results and safety. OBJECTIVE: To determine the efficacy of HFNC, as well as to evaluate the factors related to its failure and complications associated with its use in infants. PATIENTS AND METHOD: An analysis was performed on the demographic, clinical, blood gas, and radiological data, as well as the complications of patients connected to a HFNC in a critical care unit between June 2012 and September 2014. A comparison was made between the patients who failed and those who responded to HFNC. A failure was considered as the need for further respiratory support during the first 48hours of connection. The Kolmogorov Smirnov, Mann-Whitney U, chi squared and the Exact Fisher test were used, as well as correlations and a binary logistic regression model for P≤.05. RESULTS: The study included 109 patients, with a median age and weight: 1 month (0.2-20 months) and 3.7kg (2-10kg); 95 percentile: 3.7 months and 5.7kg, respectively. The most frequent diagnosis and radiological pattern was bronchiolitis (53.2%) and interstitial infiltration (56%). Around 70.6% responded. There was a significant difference between failure and response in the diagnosis (P=.013), radiography (P=018), connection context (P<.0001), pCO2 (median 40.7mmHg [15.4-67 mmHg] versus 47.3mmHg [28.6-71.3mmHg], P=.004) and hours on HFNC (median 60.75hrs [5-621.5 hrs] versus 10.5hrs [1-29 hrs], P<.0001). The OR of the PCO2 ≥ 55mmHg for failure was 2.97 (95% CI; 1.08-8.17; P=.035). No patient died and no complications were recorded. CONCLUSION: The percentage success observed was similar to that published. In this sample, the failure of HFNC was only associated with an initial pCO2 ≥ 55mmHg. On there being no complications reported as regards it use, it is considered safe, although a randomised, controlled, multicentre study is required to compare and contrast these results.


Asunto(s)
Cateterismo/métodos , Cuidados Críticos/métodos , Enfermedades Pulmonares/terapia , Terapia por Inhalación de Oxígeno/métodos , Administración Intranasal , Análisis de los Gases de la Sangre , Bronquiolitis/epidemiología , Bronquiolitis/terapia , Dióxido de Carbono/sangre , Femenino , Humanos , Lactante , Recién Nacido , Unidades de Cuidado Intensivo Pediátrico , Modelos Logísticos , Estudios Longitudinales , Enfermedades Pulmonares/epidemiología , Enfermedades Pulmonares/fisiopatología , Enfermedades Pulmonares Intersticiales/epidemiología , Enfermedades Pulmonares Intersticiales/terapia , Masculino , Insuficiencia del Tratamiento , Resultado del Tratamiento
2.
Semergen ; 45(1): 23-29, 2019.
Artículo en Español | MEDLINE | ID: mdl-30268361

RESUMEN

OBJECTIVES: 1) To determine the prevalence of intimate partner violence (IPV) in patients seen in the emergency department with chest pain. 2)To analyse the possible association between IPV and presence/control of vascular risk factors (VRF), psychic manifestations of stress, delay in requesting care, care received, and prognosis. METHODS: The study was conducted on 125 women, and included a targeted interview, the Partner Violence Screen (PVS) test, a 30-day follow-up telephone interview, and a one-year follow-up clinical history review. RESULTS: A total of 27 patients (21.6%) had a history of IPV, which was present in 4 of them. Women with a history of IPV were younger (53.7±15.0 vs. 64.0±18.4; P=.020), had more anxiety or a depressive syndrome (57.7% vs 13.5%; P<0.001), and consulted later (35.0±65.2days vs 7.9±25.0days; P=.047). Among older women (≥65years), there was more dyslipidaemia (100% vs 60.4%; P=.039) and worse blood pressure control (good control 20% vs 78.4%; P=.007) in those with a history of IPV. There were no differences in the diagnoses, tests, length of stay, admissions or prognosis among patients with or without a history of IPV, and there were no differences according to chronology of IPV. CONCLUSIONS: The current or previous existence of IPV in patients who consult for chest pain in the emergency department is high. The existence of IPV is associated with a delay in consultation and greater anxiety, and may contribute to poor control of VRF, but does not affect the prognosis in the medium term.


Asunto(s)
Dolor en el Pecho/epidemiología , Servicio de Urgencia en Hospital/estadística & datos numéricos , Violencia de Pareja/estadística & datos numéricos , Tamizaje Masivo/métodos , Adulto , Factores de Edad , Anciano , Femenino , Estudios de Seguimiento , Humanos , Entrevistas como Asunto , Tiempo de Internación , Persona de Mediana Edad , Aceptación de la Atención de Salud/estadística & datos numéricos , Prevalencia , Pronóstico , Factores de Riesgo , Parejas Sexuales , Factores de Tiempo
3.
J Hazard Mater ; 343: 227-234, 2018 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-28961503

RESUMEN

In this research, controlled release formulations (CRFs) of the herbicides chloridazon and metribuzin, identified as potential leachers, have been evaluated in soils with different texture. To prepare the CRFs, ethylcellulose (EC) and dibutylsebacate (DBS) have been used as coating agents in lignin-polyethylene glycol based formulations. Mobility experiments have been carried out in two light textured soils (sandy and sandy-loam). Breakthrough curves have shown that the use of CRFs reduces the presence of chloridazon and metribuzin in the leachate compared to technical and commercial products, being the lignin CRF coated with EC and DBS the most efficient to diminish the herbicide leaching. Mass balance study has shown a higher amount of chloridazon and metribuzin recovered in soils when these herbicides were tested as CRFs compared to technical and commercial products. The gradual release of herbicides from the CRFs resulting in a rather available levels of chloridazon and metribuzin in soil for a longer time. A good correlation between percentages of herbicide recovered in leachates and T50 values (time corresponding to 50% release of herbicide in water) was obtained, which allows to select the most appropriate CRF in each agro-environmental practice to reduce the potential pollution of groundwater by chloridazon and metribuzin.

4.
Chemosphere ; 69(5): 785-94, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17585994

RESUMEN

The herbicides chloridazon and metribuzin, identified as groundwater pollutants, were incorporated in alginate-based granules to obtain controlled release properties. In this research the effect of incorporation of sorbents such as bentonite, anthracite and activated carbon in alginate basic formulation were not only studied on encapsulation efficiency but also on the release rate of herbicides which was studied using water release kinetic tests. In addition, sorption studies of herbicides with bentonite, anthracite and activated carbon were made. The kinetic experiments of chloridazon and metribuzin release in water have shown that the release rate is higher in metribuzin systems than in those prepared with chloridazon, which has lower water solubility. Besides, it can be deduced that the use of sorbents reduces the release rate of the chloridazon and metribuzin in comparison to the technical product and to the alginate formulation without sorbents. The highest decrease in release rate corresponds to the formulations prepared with activated carbon as a sorbent. The water uptake, permeability, and time taken for 50% of the active ingredient to be released into water, T(50), were calculated to compare the formulations. On the basis of a parameter of an empirical equation used to fit the herbicide release data, the release of chloridazon and metribuzin from the various formulations into water is controlled by a diffusion mechanism. Sorption capacity of the sorbents for chloridazon and metribuzin, ranging from 0.53mgkg(-1) for the metribuzin sorption on bentonite to 2.03x10(5)mgkg(-1) for the sorption of chloridazon on the activated carbon, was the most important factor modulating the herbicide release.


Asunto(s)
Herbicidas/química , Piridazinas/química , Triazinas/química , Contaminación Química del Agua/prevención & control , Adsorción , Bentonita/química , Carbono/química , Herbicidas/normas , Tamaño de la Partícula , Piridazinas/normas , Solubilidad , Triazinas/normas
5.
Environ Pollut ; 142(3): 449-56, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16387398

RESUMEN

In this study we have evaluated the effects of dissolved organic matter (DOM) on sorption of imidacloprid, 3,4-dichloroaniline (3,4-DCA) and 4-bromoaniline (4-BA) on a typical calcareous soil (Luvic Xerosol) from south-eastern Spain. Two different types of DOM were used, that is to say, dissolved natural organic matter extracts from a commercial peat (DNOM) and a high-purity tannic acid (TA) solution. The experiments were carried out in a 0.01 M CaCl2 aqueous medium at 25 degrees C. The results indicated that the presence of both DNOM and TA, over a concentration range of 15-100 mg L(-1), produced an increase in the amount of 3,4-DCA and 4-BA sorbed and a decrease in the amount of imidacloprid retained on the soil studied. A modified distribution coefficient, K(doc), has been proposed as a safer parameter for soil sorption predictions of organic pollutants and it could be of help to model the fate of these in the environment.


Asunto(s)
Monitoreo del Ambiente/métodos , Compuestos Orgánicos/análisis , Contaminantes del Suelo/análisis , Suelo/análisis , Adsorción , Compuestos de Anilina/análisis , Calcio , Restauración y Remediación Ambiental , Sedimentos Geológicos , Herbicidas/análisis , Sustancias Húmicas , Imidazoles/análisis , Neonicotinoides , Nitrocompuestos , Solubilidad , Taninos
6.
Biosens Bioelectron ; 78: 505-512, 2016 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-26667092

RESUMEN

In this work we present the construction of immunosensors based on graphite-epoxy which incorporate RIgG to the composite matrix. In order to improve the electrochemical properties of the immunocomposite electrodes, characterization and optimization was carried out in terms of electrochemical impedance spectroscopy and cyclic voltammetry. Consequently, taking into the account the properties required by a sensitive electrode such as high electron-transfer rate, high signal-to-noise ratio and suitable sensitivity; the optimal proportion of the transducer material (graphite-epoxy ratio) was chosen using constant amount of RIgG. The optimum composition range values, which provide these requirements, were from 16% to 17% of graphite loading. Then, the analytical properties of these immunosensors were evaluated measuring RIgG by using a competitive assay and using alkaline phosphatase-labeled antibody. Amperometric measurements were performed using hydrogen peroxide as substrate. Moreover, it has been the first time that it has been performed an optimization of the antigen-antibody ratio used in the assay, being this reduced significantly.


Asunto(s)
Técnicas Biosensibles/métodos , Electroquímica/métodos , Inmunoglobulina G/aislamiento & purificación , Nanotubos de Carbono/química , Fosfatasa Alcalina/química , Reacciones Antígeno-Anticuerpo , Grafito/química , Humanos , Inmunoglobulina G/inmunología , Relación Señal-Ruido
7.
Biosens Bioelectron ; 20(8): 1668-73, 2005 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-15626626

RESUMEN

The determination of phenolic compounds is significant given its toxicity, even at very low concentration levels. Amperometric determination of phenols is a simple technique available. Direct oxidation of phenols can be used, but another possibility is the use of polyphenol oxidase (tyrosinase) enzyme biosensors that oxidises the phenolic compounds into their corresponding quinones. Reduction of the resulting quinones accomplishes the amplification of the amperometric signal, as long as the result of the reduction process is the corresponding cathecol, this being able to be oxidised again by the polyphenol oxidase immobilized on the surface of the biosensor. In this communication, simultaneous determination of different phenols was carried out combining biosensor measurements with chemometric tools, in what is known as electronic tongue. The departure information used was the overlapped reduction voltammogram generated with the amperometric biosensor based on polyphenol oxidase. Artificial Neural Networks (ANN) were used for extraction and quantification of each compound. Phenol, cathecol and m-cresol formed the three-analyte study case resolved in this work. Good prediction ability was attained, and so, the separate quantification of these three phenols was accomplished.


Asunto(s)
Algoritmos , Técnicas Biosensibles/métodos , Catecol Oxidasa/análisis , Catecol Oxidasa/química , Electroquímica/métodos , Redes Neurales de la Computación , Fenoles/análisis , Fenoles/química , Técnicas Biosensibles/instrumentación , Electroquímica/instrumentación , Enzimas Inmovilizadas/análisis , Enzimas Inmovilizadas/química , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
8.
J Agric Food Chem ; 53(17): 6697-703, 2005 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-16104787

RESUMEN

Controlled release systems (CRS), unlike the conventional formulations, facilitate a gradual and controlled discharge of the pesticides, reducing the losses by evaporation and leaching and minimizing pesticide pollution. In this study, carbofuran-an insecticide-nematicide identified as a groundwater pollutant-was incorporated in alginate-based granules to obtain controlled release properties. The effect on carbofuran release rate caused by the incorporation of bentonite, activated carbon, and different mixtures of both sorbents in alginate basic formulation was studied by immersion of the granules in water. The water uptake, sorption capacity of the sorbent, permeability, and time taken for 50% of the active ingredient to be released into water, T(50), were calculated by the comparison of the preparations. T(50) values were higher for those formulations containing bentonite and/or activated carbon (T(50) values range from 14.76 h for the alginate formulation containing only bentonite as the sorbent to 29.5 weeks for the alginate formulation containing only activated carbon as the sorbent) than for the preparation without these sorbents (11.72 h). On the basis of a parameter of an empirical equation used to fit the insecticide-nematicide release data, it appears that the release of carbofuran from the various formulations into water is controlled by a diffusion mechanism. The sorption capacity of the sorbents for carbofuran was the most important factor modulating carbofuran release. In addition, it was observed that there is a linear correlation of the T(50) values and the content of activated carbon in dry granules.


Asunto(s)
Bentonita , Carbofurano/administración & dosificación , Carbono , Insecticidas/administración & dosificación , Adsorción , Carbofurano/química , Fenómenos Químicos , Química Física , Preparaciones de Acción Retardada , Difusión , Insecticidas/química , Contaminantes del Agua/análisis
9.
Chemosphere ; 59(5): 721-8, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15792670

RESUMEN

To evaluate the effects of dissolved organic carbon on sorption of 3,4-dichloroaniline (3,4-DCA) and 4-bromoaniline (4-BA) on soils, batch sorption experiments were carried out. The soil used was a typical calcareous soil from south-eastern Spain. Two different types of dissolved organic carbon were used, that is, dissolved organic carbon extracts from a commercial peat (DOC-PE) and high-purity tannic acid (DOC-TA). The experiments were carried out in a 0.01 M CaCl2 aqueous medium at 25 degrees C. The results obtained from the sorption experiments show that the presence of both DOC-PE and DOC-TA, over a concentration range of 15-100 mg l-1, produced in all cases, an increase in the amount of 3,4-DCA and 4-BA adsorbed on the soil studied.


Asunto(s)
Compuestos de Anilina/química , Carbono/química , Contaminantes del Suelo , Adsorción , Cromatografía Líquida de Alta Presión , Suelo , España , Taninos/química
10.
Trans R Soc Trop Med Hyg ; 98(12): 742-50, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15485705

RESUMEN

To determine clinical and epidemiological features of scorpion stings in two departments of Colombia, a descriptive study was performed in the hospitals of 10 towns from Antioquia (2 256 071 inhabitants) and five from Tolima (630 424 inhabitants). One hundred and twenty-nine cases were admitted during one year, 51 in Antioquia, 78 in Tolima and 41 were children less than 15 years old. Most stings (70.5%) occurred inside the house; 27.9% were on the hands and 26.4% on the feet. The scorpion species involved were Tityus pachyurus (51), Centruroides gracilis (31), T. fuehrmanni (29), T. asthenes (7) and Chactas spp. (1). In 10 cases the scorpion involved was not identified. Systemic envenoming signs (e.g. vomiting, tachypnea) were significantly more frequent in children than in adults (P < 0.05). Four children had hypertension, but none developed pulmonary oedema. One 3-year-old girl, stung by T. asthenes, had acute oedematous pancreatitis. Ninety-eight patients had mild envenoming. Moderate (27 patients) and severe (four patients) envenoming was significantly more frequent in children than in adults (P = 0.003; relative risk = 2.97). A pepsin-digested anti-Centruroides spp. antivenom was administered to 19 of 31 patients presenting systemic envenoming signs. No adverse reactions to antivenom were observed.


Asunto(s)
Picaduras de Escorpión/epidemiología , Adolescente , Adulto , Distribución por Edad , Animales , Antídotos/uso terapéutico , Niño , Preescolar , Colombia/epidemiología , Femenino , Humanos , Incidencia , Lactante , Masculino , Medicina Tradicional , Persona de Mediana Edad , Picaduras de Escorpión/complicaciones , Picaduras de Escorpión/terapia , Escorpiones , Factores de Tiempo , Resultado del Tratamiento
11.
J Agric Food Chem ; 48(3): 938-43, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10725178

RESUMEN

The insecticide-nematicide carbofuran was incorporated in alginate-based granules to obtain controlled-release (CR) properties. The basic formulation [sodium alginate (1.61%)-carbofuran (0. 59%)-water] was modified by addition of sorbents. The effect on carbofuran release rate, caused by the incorporation of natural and acid-treated bentonite (0.5 and 1.0 M H(2)SO(4)) in alginate formulation, was studied by immersion of the granules in water under shaking. The time taken for 50% of the active ingredient to be released into water, t(50), was longer for those formulations containing natural bentonite (6.1 h) or acid-treated bentonite (9.0 and 11.7 h for 0.5 and 1.0 M H(2)SO(4) treatments, respectively) than for the preparation without bentonite (4.7 h). It appears from the results that the release of carbofuran from the various formulations is controlled by a diffusion mechanism according to the n values obtained, which were close to 0.5 in all cases. The mobility of carbofuran from alginate-based CR formulations was investigated by using soil columns packed with a clay soil (53% clay and 0.08% organic matter). Two alginate-based CR formulations containing natural bentonite or acid-treated bentonite (0.5 M H(2)SO(4)) were compared to technical grade carbofuran. The use of alginate-based CR formulations resulted in a reduction of the leached amount of carbofuran compared with the total amount of pesticide leached using the technical product (50 and 75% for CR granules containing natural and acid-treated bentonite, respectively). Alginate-bentonite CR formulations might be efficient systems for reducing carbofuran leaching in clay soils, which would reduce the risk of groundwater pollution.


Asunto(s)
Alginatos/química , Antinematodos/química , Bentonita/química , Carbofurano/química , Insecticidas/química , Contaminación del Agua/prevención & control , Preparaciones de Acción Retardada , Humanos , Cinética , Contaminantes del Suelo/metabolismo
12.
J Agric Food Chem ; 47(3): 1236-41, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10552443

RESUMEN

The sorption and leaching of atrazine and MCPA (0.02 M CaCl(2) aqueous solution at 25 degrees C) by a calcareous soil from Southeastern Spain, after organic carbon (OC) amendment with a commercial peat (from 0.18% to 4.61% OC), were studied in batch and soil column experiments. Adsorption capacity (K(f)) values, obtained by fitting the experimental data to the Freundlich equation, ranged from 0.24 mg kg(-)(1) for MCPA sorption on the original soil to 5.47 mg kg(-)(1) for atrazine sorption on the peat-amended soil containing 4.61% OC. The breakthrough curves obtained from the step-function soil column experiments indicated that the amount of herbicide adsorbed ranged from 17.5 mg kg(-)(1) for MCPA in the original soil to 331 mg kg(-)(1) for atrazine in the peat-amended soil containing 1.67% OC. The results obtained from the pulse experiments indicate that the mobility of MCPA is much greater than that corresponding to atrazine.


Asunto(s)
Ácido 2-Metil-4-clorofenoxiacético/análisis , Atrazina/análisis , Herbicidas/análisis , Suelo/análisis , Adsorción , Cloruro de Calcio , España
13.
J Agric Food Chem ; 47(2): 791-8, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10563970

RESUMEN

The herbicide diuron was incorporated in alginate-based granules to obtain controlled release (CR) properties. The standard formulation (alginate-herbicide-water) was modified by the addition of different sorbents. The effect on diuron release rate caused by incorporation of natural and acid-treated bentonites in alginate formulation was studied by immersion of the granules in water under static conditions. The release of diuron was diffusion-controlled. The time taken for 50% release of active ingredient to be released into water, T(50), was calculated for the comparison of formulations. The addition of bentonite to the alginate-based formulation produced the higher T(50) values, indicating slower release of the diuron. The mobility of technical and formulated diuron was compared by using soil columns. The use of alginate-based CR formulations containing bentonite produced a less vertical distribution of the active ingredient as compared to the technical product and commercial formulation. Sorption capacities of the various soil constituents for diuron were also determined using batch experiments.


Asunto(s)
Alginatos/química , Bentonita/química , Diurona/química , Herbicidas/química , Portadores de Fármacos , Cinética , Agua
14.
Chemosphere ; 41(9): 1495-501, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11057588

RESUMEN

The mobility of isoproturon [3-(4-isopropylphenyl)-1,1-dimethylurea] from an alginate-based controlled release (CR) formulation was investigated by using soil columns. A layered bed system simulating the typical arrangement under a plastic greenhouse, which is composed of sand, peat, amended soil and native soil was used. The CR formulation was based on sodium alginate (1.87%), isoproturon (1.19%), natural bentonite (3.28%), and water (93.66%), and was compared to technical grade isoproturon. The use of the alginate-bentonite CR formulation produced less vertical mobility of the active ingredient as compared to the technical product. There was no presence of herbicide in the leachate when the alginate-bentonite CR formulation was used. However, 0.90% of isoproturon appeared when the treatment was carried out with technical grade material. Isoproturon mobility was modelled using the programme CMLS, which showed the peat layer to retard pesticide leaching. Analysis of the soil columns showed the highest isoproturon concentration in the peat layer.


Asunto(s)
Alginatos/química , Bentonita/química , Compuestos de Metilurea/química , Compuestos de Fenilurea , Suelo/análisis , Adsorción , Ácido Glucurónico , Herbicidas/análisis , Ácidos Hexurónicos , Cinética , Compuestos de Metilurea/análisis , Análisis de Regresión
15.
Chemosphere ; 43(3): 347-53, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11302580

RESUMEN

The mobility of atrazine [6-chloro-N2-ethyl-N4-isopropyl-1,3,5-triazine-2,4-diamine] from alginate-bentonite-based controlled release (CR) formulations was investigated by using soil columns. Two CR formulations based on sodium alginate (14.0 g kg(-1), atrazine (6.0 g kg(-1), natural or acid-treated bentonite (50 g kg(-1), and water (924 g kg(-1) were compared to technical grade product and commercial liquid (CL) formulation (Gesaprim 500FW). All herbicide treatments were applied to duplicate layered bed systems simulating the typical arrangement under a plastic greenhouse, which is composed of sand (10 cm), peat (2 cm), amended soil (20 cm) and native soil (20 cm). The columns were leached with 39 cm (1500 ml) and 156 cm (6000 ml) of 0.02 M CaCl2 solution to evaluate the effect of water volume applied on herbicide movement. When 39 cm of 0.02 M CaCl2 solution was applied, there was no presence of herbicide in the leachate for the alginate-bentonite CR treatments. However, 0.11% and 0.14% of atrazine appeared in the leachate when the treatment was carried out with technical grade and CL formulations, respectively. When 156 cm of 0.02 M CaCl2 solution was applied, the use of the alginate-acid treated bentonite CR formulation retards and reduces the presence of atrazine in the leachate as compared to technical product. Analysis of the soil columns showed the highest atrazine concentration in the peat layer. Alginate-bentonite CR formulations might be an efficient system for reducing atrazine leaching in layered soil and thus, it could reduce the risks of pollution of groundwater.


Asunto(s)
Alginatos/química , Atrazina/química , Bentonita/química , Conservación de los Recursos Naturales/métodos , Contaminantes del Suelo/análisis , Contaminación Química del Agua/prevención & control , Química Farmacéutica/métodos , Ácido Glucurónico , Ácidos Hexurónicos , Dióxido de Silicio/química , Suelo/análisis
16.
Chemosphere ; 51(2): 85-93, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12586141

RESUMEN

The adsorption of 6-chloro-N(2)-ethyl-N(4)-isopropyl-1,3,5-triazine-2,4-diamine (atrazine) on heat treated kerolite samples at 110 degrees C (K-110), 200 degrees C (K-200), 400 degrees C (K-400) and 600 degrees C (K-600) from aqueous solution at 25 degrees C has been studied. The evolution of surface properties of kerolite samples such as specific surface area and porosity after heat treatment was analysed. The clays were characterised by using usual techniques: FTIR spectroscopy, XRD diffraction, TG and DTG analysis, surface analysis and Hg porosimetry. The adsorption experimental data points have been fitted to the Freundlich equation in order to calculate the adsorption capacities (K(f)) of the samples; K(f) values range from 468 mgkg(-1) for the K-110 sample up to 2291 mgkg(-1) for the K-600 sample. The values obtained for the removal efficiency (R), (percentage of pesticide removed), ranged from 48% for K-110 up to 78% for K-600. The adsorption experiments showed that the stronger heat treatment, the most effective adsorption of atrazine, so, as this type of clay is relatively plentiful, these activated samples might be used in order to remove this pesticide from water.


Asunto(s)
Silicatos de Aluminio/química , Atrazina/química , Herbicidas/química , Adsorción , Arcilla , Calor , Soluciones , Agua
17.
J Environ Qual ; 31(3): 880-8, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12026091

RESUMEN

To evaluate the effects of dissolved organic carbon on sorption and mobility of the insecticide imidacloprid [1-(6-chloro-3-pyridinyl) methyl-N-nitro-2-imidazolidinimine] in soils, adsorption and column experiments were performed by using a typical calcareous soil from southeastern Spain and two different types of dissolved organic carbon, that is, dissolved organic carbon extracts from a commercial peat (DOC-PE) and high-purity tannic acid (DOC-TA). The experiments were carried out from a 0.01 M CaCl2 aqueous medium at 25 degrees C. The results obtained from the sorption experiments show that the presence of both DOC-PE and DOC-TA, over a concentration range of 15 to 100 mg L(-1), produces in all cases a decreasing amount of imidacloprid adsorbed in the soil studied. From the column experiments the retardation coefficients (RC) were calculated for imidacloprid by using either 0.01 M CaCl2 aqueous solution (RC = 2.10), 0.01 M CaCl2 DOC-PE solution (RC = 1.65), or 0.01 M CaCl2 DOC-TA solution (RC = 1.87). The results indicate that mobility of imidacloprid is increased 21.4 and 11.0% in the presence of DOC-PE and DOC-TA solutions, respectively. Dissolved organic carbon reduces imidacloprid sorption by competing with the pesticide molecules for sorption sites on the soil surface, allowing enhanced leaching of imidacloprid and potentially increasing ground water contamination.


Asunto(s)
Carbono/química , Imidazoles/química , Insecticidas/química , Plantas , Contaminantes del Suelo/análisis , Suelo/análisis , Adsorción , Cromatografía Líquida de Alta Presión , Humanos , Taninos Hidrolizables/química , Neonicotinoides , Nitrocompuestos , Soluciones , España , Contaminación del Agua/prevención & control
18.
Pest Manag Sci ; 59(10): 1162-8, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14561075

RESUMEN

The adsorption of imidacloprid [1-(6-chloro-3-pyridinylmethyl)-N-nitroimidazolidin-2-ylideneamine] on heat-treated kerolite samples at 110 degrees C (K-110), 200 degrees C (K-200), 400 degrees C (K-400) and 600 degrees C (K-600) from pure water solution at 25 degrees C has been studied. The evolution of the surface properties of the kerolite samples, such as specific surface area and porosity, after heat treatment were analysed. The clays were characterised by using FTIR spectroscopy, X-ray diffraction, thermogravimetric and differential thermogravimetric analysis, surface analysis and Hg porosimetry. The experimental adsorption data points were fitted to the Freundlich equation in order to calculate the adsorption capacities (Kf) of the samples; Kf values ranged from 242 mg kg(-1) for the K-110 sample to 1005 mg kg(-1) for the K-600 sample. The values obtained for the removal efficiency (R) ranged from 62.8% for K-110 to 87.2% for K-600. The adsorption experiments showed that the stronger the heat treatment, the more effective was the adsorption of imidacloprid from pure water. This work shows the potential use of heat-activated kerolite for the removal of imidacloprid from environmental waters and drinking water resources.


Asunto(s)
Silicatos de Aluminio/análisis , Imidazoles/metabolismo , Contaminantes Químicos del Agua/metabolismo , Agua/metabolismo , Adsorción , Silicatos de Aluminio/metabolismo , Arcilla , Calor , Imidazoles/aislamiento & purificación , Neonicotinoides , Nitrocompuestos , Porosidad , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Propiedades de Superficie , Termogravimetría/métodos , Contaminantes Químicos del Agua/aislamiento & purificación , Contaminación Química del Agua/prevención & control , Difracción de Rayos X/métodos
19.
SEMERGEN, Soc. Esp. Med. Rural Gen. (Ed. Impr.) ; 45(1): 23-29, ene.-feb. 2019. tab
Artículo en Español | IBECS (España) | ID: ibc-188044

RESUMEN

OBJETIVOS: 1) Conocer la prevalencia de violencia de pareja (VP) en las pacientes que consultan a urgencias por dolor torácico. 2)Analizar la posible asociación entre VP y presencia/control de factores de riesgo vascular (FRV), manifestaciones psíquicas de estrés, demora en la solicitud de atención, manejo del episodio y pronóstico. MÉTODOS: Se incluyó a 125 mujeres. Se realizó entrevista dirigida, test del Partner Violence Screen (PVS), seguimiento telefónico a los 30 días y revisión del historial clínico al año. RESULTADOS: Veintisiete pacientes (21,6%) tenían historia de VP, que era vigente en 4 de ellas. Las mujeres que habían sufrido VP eran más jóvenes (53,7 ± 15,0 vs 64,0 ± 18,4; p = 0,020), presentaban más frecuentemente síndrome ansioso-depresivo (57,7% vs 13,5%; p < 0,001) y tardaron más en consultar (35,0 ± 65,2 días vs 7,9 ± 25,0días; p = 0,047). Entre las mujeres mayores (≥ 65 años) existía más dislipidemia (100% vs 60,4%; p = 0,039) y peor control de la presión arterial (buen control 20% vs 78,4%; p = 0,007) en las que tenían historia de VP. No hubo diferencias en los diagnósticos, pruebas, tiempo de estancia, ingresos o evolución entre las pacientes con historia de VP o sin ella, ni hubo diferencias según la vigencia de la VP. CONCLUSIONES: La existencia actual o previa de VP en las pacientes que consultan por dolor torácico en urgencias es elevada. La existencia de VP va asociada a un retraso en la consulta y a mayor ansiedad, y puede contribuir a un mal control de los FRV, pero no afecta la evolución a medio plazo


OBJECTIVES: 1) To determine the prevalence of intimate partner violence (IPV) in patients seen in the emergency department with chest pain. 2) To analyse the possible association between IPV and presence/control of vascular risk factors (VRF), psychic manifestations of stress, delay in requesting care, care received, and prognosis. METHODS: The study was conducted on 125 women, and included a targeted interview, the Partner Violence Screen (PVS) test, a 30-day follow-up telephone interview, and a one-year follow-up clinical history review. RESULTS: A total of 27 patients (21.6%) had a history of IPV, which was present in 4 of them. Women with a history of IPV were younger (53.7 ± 15.0 vs. 64.0 ± 18.4; P = .020), had more anxiety or a depressive syndrome (57.7% vs 13.5%; P < 0.001), and consulted later (35.0 ± 65.2days vs 7.9 ± 25.0days; P = .047). Among older women ( ≥ 65years), there was more dyslipidaemia (100% vs 60.4%; P = .039) and worse blood pressure control (good control 20% vs 78.4%; P = .007) in those with a history of IPV. There were no differences in the diagnoses, tests, length of stay, admissions or prognosis among patients with or without a history of IPV, and there were no differences according to chronology of IPV. CONCLUSIONS: The current or previous existence of IPV in patients who consult for chest pain in the emergency department is high. The existence of IPV is associated with a delay in consultation and greater anxiety, and may contribute to poor control of VRF, but does not affect the prognosis in the medium term


Asunto(s)
Humanos , Femenino , Adulto , Persona de Mediana Edad , Anciano , Servicio de Urgencia en Hospital/estadística & datos numéricos , Violencia de Pareja/estadística & datos numéricos , Dolor en el Pecho/epidemiología , Tamizaje Masivo/métodos , Estudios de Seguimiento , Entrevistas como Asunto , Tiempo de Internación , Aceptación de la Atención de Salud/estadística & datos numéricos , Prevalencia , Pronóstico , Factores de Riesgo , Parejas Sexuales , Factores de Tiempo , Factores de Edad , Estudios Prospectivos , Factores Socioeconómicos
20.
Chemosphere ; 92(8): 918-24, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23562547

RESUMEN

The leaching of herbicides through soil can be minimized using controlled release formulations (CRFs). In this research, bentonite and anthracite have been used as modifying agents in alginate-based CRFs prepared with chloridazon and metribuzin. These CRFs have been evaluated in a calcareous soil. The Kf and Koc values obtained from sorption experiments in soil have demonstrated a high leaching potential for both herbicides, mainly for metribuzin. Release kinetics in soil have showed that the control of release rate of chloridazon and metribuzin was possible by using bentonite and anthracite in CRFs, being this effect greater when we use anthracite as modifying sorbent. Using an empirical equation, the time taken for 50% of the active ingredient to be released (T50(soil)) was calculated. T50 values ranged between 2.88 d for metribuzin-bentonite alginate-based granules and 14.37 d for chloridazon-anthracite alginate-based granules, being the release rate higher in metribuzin CRFs than in those prepared with chloridazon, which has lower water solubility. Besides, a linear correlation between T50 values in water and soil was obtained. Mobility experiments carried out in a calcareous soil have shown that the use of CRFs reduces the presence of herbicides in the leachate compared to technical products, mainly for chloridazon. We found that one could design a right profile in the release rate of active ingredients from CRFs in each agro-environmental situation, and thus prevent the environmental pollution derived from the use of chloridazon and metribuzin.


Asunto(s)
Bentonita/química , Carbón Mineral , Contaminación Ambiental/prevención & control , Herbicidas/química , Piridazinas/química , Contaminantes del Suelo/química , Triazinas/química , Adsorción , Alginatos/química , Cromatografía Líquida de Alta Presión , Preparaciones de Acción Retardada/química , Monitoreo del Ambiente , Ácido Glucurónico/química , Ácidos Hexurónicos/química , Suelo/química , España
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