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1.
Environ Geochem Health ; 45(6): 3345-3359, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36306038

RESUMEN

Water quality deterioration hinders economic and social development in developing countries that are facing freshwater security and shortages. Based on the collection of 29 water samples, this study focused on the relationship between sewage treatment plant and groundwater system surrounding it using multidisciplinary approach that combines the characterization of groundwater system and its connection with surrounding canal and drains, using chemical and isotopic characterization revealing that there is a direct relation between the surface water system and surrounding groundwater system. About 58% of the groundwater samples and all surface water samples in the investigated area are threatened by high concentrations of trace elements. The multivariate statistical analysis elucidates that anthropogenic effect and fertilizers sewage contamination are the main causes of groundwater pollution. Nearly, 31% and 11.5% of groundwater samples were posing oral chronic non-carcinogenic health risk and dermal chronic risk for adult, respectively, while all surface water samples were posing oral chronic non-carcinogenic health risk, with no dermal hazard. The uncharged species of Fe and Al are expected to be more mobile in groundwater because they would not be attracted to the surface charge of minerals. Inorganic ligands (HCO3-, SO42-, Cl-, and NO3-) act as nucleation centers that were linked with those trace elements creating new species with higher solubility degree in water that are transported away randomly for long distances in the water path.


Asunto(s)
Agua Subterránea , Oligoelementos , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Aguas del Alcantarillado/análisis , Oligoelementos/análisis , Agua Subterránea/química , Calidad del Agua , Contaminantes Químicos del Agua/análisis
2.
Carbohydr Polym ; 103: 385-91, 2014 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-24528744

RESUMEN

As microwaves are known to give fast and rapid volume heating, the present study is undertaken to investigate the use of microwave heating for pretreatment cotton fabrics to reduce the pretreatment time, chemicals and water. The onset of the microwave heating technique on the physicochemical and performance properties of desized, scoured and bleached cotton fabric is elucidated and compared with those obtained on using conventional thermal heating. Combined one-step process for desizing, scouring and bleaching of cotton fabric under microwave heating was also investigated. The dual effect of adding urea, (as microwave absorber and hydrogen peroxide activator) has been exploiting to accelerate the pretreatment reaction of cotton fabric. DSC, FT-IR and SEM have been used to investigate the onset of microwave on the morphological and chemical change of cotton cellulose after pretreatment and bleaching under microwave heating. Results obtained show that, a complete fabric preparation was obtained in just 5 min on using microwave in pretreatments process and the fabric properties were comparable to those obtained in traditional pretreatment process which requires 2.5-3h for completion.


Asunto(s)
Fibra de Algodón , Microondas , Calefacción
3.
Eur J Neurol ; 6(4): 443-8, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10362897

RESUMEN

INTRODUCTION: The aim of this study was to assess the effect of Albunex, a vascular contrast agent based on albumin-coated air microbubbles, on pulsed Doppler and colour-coded duplex sonography of the cranial vasculature. METHODS: Twenty healthy male volunteers received intravenous injections of contrast in single doses ranging from 0.08 to 0.30 ml/kg. Pulsed wave Doppler sonography examination and colour-coded duplex sonography were carried out in the right internal carotid artery (ICA) and middle cerebral artery (MCA) before and after i.v. contrast. The relative intensity increase of the Doppler signal was measured in decibels. RESULTS: Transpulmonary passage of contrast occurred in sufficient amounts to enhance the intensity of the Doppler signal significantly, but the duration of this effect was short. Contrast enhancement also improved visualization of both the ICA and MCA in all subjects. For the transcranial examinations, this resulted in visualization of a greater length of the middle cerebral arteries and additional vessels in the Circle of Willis. CONCLUSIONS: These results confirm that contrast enhancement can significantly improve the quality of Doppler examination and colour-coded duplex sonography of both the intracranial and extracranial vessels. However, the use of Albunex in neurosonology will be of limited value due to its relatively short duration.


Asunto(s)
Albúminas , Arterias Cerebrales/diagnóstico por imagen , Venas Cerebrales/diagnóstico por imagen , Medios de Contraste , Adulto , Albúminas/administración & dosificación , Albúminas/efectos adversos , Circulación Cerebrovascular/fisiología , Medios de Contraste/administración & dosificación , Medios de Contraste/efectos adversos , Humanos , Inyecciones Intravenosas , Imagen por Resonancia Magnética , Masculino , Microesferas , Ultrasonografía Doppler en Color , Ultrasonografía Doppler de Pulso
4.
Tidsskr Nor Laegeforen ; 118(9): 1398-401, 1998 Mar 30.
Artículo en Noruego | MEDLINE | ID: mdl-9599505

RESUMEN

The clinical diagnosis of brain embolism has traditionally been based on evidence suggesting a potential embolic source. However, it is now possible to detect circulating cerebral microemboli by means of transcranial Doppler ultrasound. We explain the theory behind microembolus detection, and discuss initial clinical experience of this method. During invasive cardiovascular investigations and surgery this method can warn the physician that microemboli are entering the cerebral circulation, and preventive measures can be taken. Cerebral microemboli are quite often detected in stroke prone patients, and their presence probably indicates increased risk of stroke. In the acute phase of ischemic stroke, microembolus detection may help to decide the etiology and the source of the emboli. When microemboli are detected in cases of acute embolic stroke, serial detections can be performed which, in future studies, might be of help when evaluating the effect of the treatment.


Asunto(s)
Embolia y Trombosis Intracraneal/diagnóstico por imagen , Ultrasonografía Doppler Transcraneal , Humanos , Modelos Cardiovasculares , Modelos Neurológicos , Ultrasonografía Doppler Transcraneal/instrumentación , Ultrasonografía Doppler Transcraneal/métodos
5.
Invest Radiol ; 33(3): 129-35, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9525750

RESUMEN

RATIONALE AND OBJECTIVES: Air microemboli may damage the cerebral microvasculature. The aim of this study was to evaluate the safety of ultrasound contrast agents composed of air microspheres with regard to cerebral damage when administered into the arterial system (ie, when not filtered by the capillary system of the lungs). METHODS: Three experimental methods were used in 75 rats after injection of either Albunex, Echovist, or Levovist into the left heart ventricle. The alkaline phosphatase (ALP) method to demonstrate small segmental brain capillary and arteriolar dilatations (SCADs), intravenous injections of Evans blue and fluorescence microscopy to detect increased vascular permeability (blood-brain barrier damage), and histologic examination of the brain to detect microinfarction. Intracardiac injections of saline, air, and corn oil were used as controls. RESULTS: Brain microinfarcts and SCADs formation of the brain microvasculature occurred only after control injections with corn oil. None of the brains from animals that received ultrasound contrast agent showed gross discoloration, as an indication of increased vascular permeability, with the Evans blue/fluorescence microscopy method. Definite leakage of Evans blue occurred only after large doses (150 microL) of air. CONCLUSIONS: This study indicates that ultrasound contrast media composed of air microspheres do not cause lesions of the brain microvasculature or parenchyma.


Asunto(s)
Albúminas/farmacología , Arteriolas/efectos de los fármacos , Capilares/efectos de los fármacos , Circulación Cerebrovascular/efectos de los fármacos , Medios de Contraste/farmacología , Polisacáridos/farmacología , Ultrasonografía Doppler , Animales , Arteriolas/patología , Barrera Hematoencefálica/efectos de los fármacos , Capilares/patología , Permeabilidad Capilar/efectos de los fármacos , Infarto Cerebral/etiología , Masculino , Microesferas , Ratas , Ratas Wistar , Vasodilatación
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