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1.
Public Health ; 172: 89-92, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30665689

RESUMEN

Migrants face many barriers when accessing health care, both structural and political, leading to unmet need and poor quality care. Yet these barriers often can be overcome. This short communication reports a workshop confronting these issues at the First World Congress on Migration, Ethnicity, Race and Health. It explores the structural factors that create barriers and the competencies that health professionals need to overcome them. It then examines how one non-governmental organization did confront, successfully, a restrictive policy adopted in the United Kingdom, through advocacy and practical action. It concludes by examining the related issue of cultural competency, drawing on experiences of a mental health unit in Athens, Greece.


Asunto(s)
Accesibilidad a los Servicios de Salud/organización & administración , Migrantes , Competencia Cultural , Grecia , Política de Salud , Humanos , Organizaciones , Reino Unido
2.
J Hazard Mater ; 289: 1-8, 2015 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-25702634

RESUMEN

In this paper, the sorptive kinetic and diffusional characteristics of caesium ion removal from aqueous solution by carbon-supported clinoptilolite composites are presented. Natural clinoptilolite was supported on carbonaceous scaffolds prepared from date stones. Thermal treatment was applied to produce voids in the carbon which was conditioned using polydiallyldimethylammonium chloride to facilitate the clinoptilolite attachment. This method allowed the formation of a consistent zeolite layer on the carbon surface. The composite was applied in the removal of non-radioactive caesium ions showing an enhanced uptake from 55 mg g(-1) to 120.9 mg g(-1) when compared to clinoptilolite. Kinetic studies using Pseudo First Order model revealed an enhanced rate constant for carbon-clinoptilolite (0.0252 min(-1)) in comparison with clinoptilolite (0.0189 min(-1)). The Pseudo-First Order model described the process for carbon-clinoptilolite, meanwhile Pseudo Second Order model adjusted better for pure clinoptilolite. Diffusivity results suggested that mass transfer resistances involved in the Cs(+) sorption are film and intraparticle diffusion for natural clinoptilolite and intraparticle diffusion as the mechanism that controls the process for carbon-clinoptilolite composite. The most significant aspect being that the vitrified volume waste can be reduced by over 60% for encapsulation of the same quantity of caesium due to the enhanced uptake of zeolite.


Asunto(s)
Cesio/aislamiento & purificación , Zeolitas/química , Adsorción , Algoritmos , Electroquímica , Concentración de Iones de Hidrógeno , Cinética , Tamaño de la Partícula , Difracción de Rayos X
3.
Chem Commun (Camb) ; (25): 2662-3, 2006 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-16786079

RESUMEN

The production and characterisation of a carbon negative of diatomaceous earth which has a highly intricate and novel porous structure.

4.
Chem Commun (Camb) ; (14): 1912-3, 2005 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-15795785

RESUMEN

A method for the production of mesoporous carbon, with metal particles encapsulated in the walls to prevent leaching, is demonstrated by the synthesis of a cobalt containing CMK1 structure.

5.
J Nanosci Nanotechnol ; 5(1): 92-5, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15762166

RESUMEN

The development of low cost hierarchical porous materials based upon the zeolitisation of diatomaceous earth for fluid waste benification is described. Two preparative approaches invole: first, using the diatom as a support for zeolite nanocrystals; second, direct pseudomorphic transformation of the diatom into a zeolite. These hierarchical porous materials are potentially useful for important industrial processes in ion-exchange, catalysis and waste benefication.


Asunto(s)
Cristalización/métodos , Diatomeas/química , Diatomeas/ultraestructura , Nanoestructuras/química , Nanoestructuras/ultraestructura , Zeolitas/química , Tamaño de la Partícula , Porosidad
6.
J Am Chem Soc ; 123(43): 10571-83, 2001 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-11673989

RESUMEN

Treatment of NaW2Cl7(THF)5 with 4 equiv of (t)Bu3SiNHLi afforded the C2 W(III) dimer [((t)Bu3SiNH)2WCl]2 (1, d(W triple bond W) = 2.337(2) A), which is a rare, primary amide M2X4Y2 species. Its degradation provided evidence of NH bond activation by the ditungsten bond. Addition of 2 equiv of (t)Bu3SiNHLi or TlOSi(t)Bu3 to 1 yielded H2 and hydride ((t)Bu3SiN)2((t)Bu3SiNH)WH (2, d(WH) = 1.67(3) A) or ((t)Bu3SiN)2((t)Bu3SiO)WH (3). Thermolysis (60 degrees C, 16 h) of 1 in py gave ((t)Bu3SiN)2WHCl(py) (4-py, 40-50%), ((t)Bu3SiN)2WCl2(py) (6-py, 10%), and ((t)Bu3SiN)2HW(mu-Cl)(mu-H)2W(NSi(t)Bu3)py2 (5-py2, 5%), whereas thermolysis in DME produced ((t)Bu3SiN)2WCl(OMe) (7, 30%), ((t)Bu3SiN)2WCl2 (6, 20%), and ((t)Bu3SiN)2HW(mu-Cl)(mu-H)2W(NSi(t)Bu3)DME (5-DME, 3%). Compound 7 was independently produced via thermolysis of 4-py and DME (-MeOEt, -py), and THF and ethylene oxide addition to hydride 2 gave ((t)Bu3SiN)2((t)Bu3SiNH)WO(n)Bu (8) and ((t)Bu3SiN)2((t)Bu3SiNH)WOEt (9), respectively. Dichloride 6 was isolated from SnCl4 treatment of 1 with the loss of H2. Sequential NH bond activations by the W2 core lead to "((t)Bu3SiN)2WHCl" (4) and subsequent thermal degradation products. Thermolysis of 1 in the presence of H2C=CH(t)Bu and PhC triple bond CPh trapped 4 and generated ((t)Bu3SiN)2W((neo)Hex)Cl (10) and a approximately 6:1 mixture of ((t)Bu3SiN)2WCl(cis-CPh=CPhH) (11-cis) and ((t)Bu(3)SiN)2WCl(trans-CPh=CPhH) (11-trans), respectively. Thermolysis of the latter mixture afforded ((t)Bu3SiNH)((t)Bu3SiN)WCl(eta2-PhCCPh) (12) as the major constituent. Alkylation of 1 with MeMgBr produced ((t)Bu3SiN)2W(CH3)2 (13), as did addition of 2 equiv of MeMgBr to 6. X-ray crystal structure determinations of 1, 2, 5-py2, 6-py, 11-trans, and 12 confirmed spectroscopic identifications. A general mechanism that features a sequence of NH activations to generate 4, followed by chloride metathesis, olefin insertion, etc., explains the formation of all products.

7.
Analyst ; 126(6): 733-5, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11445928

RESUMEN

Potentiometric investigations using pressed zeolite discs are reported. Potential measurements have been performed in non-aqueous solutions--this is the first report, to our knowledge, of potentiometric detection of ions in non-aqueous media with zeolite materials. Nernstian behaviour is also displayed in aqueous solutions for ions that are only able to penetrate a fraction of the internal volume of the zeolite employed.

8.
Analyst ; 126(11): 1857-60, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11763055

RESUMEN

The silicalite-modified water/organic interface represents a novel system, which is of potential utility for electroanalytical studies. As a means of investigating the analytical potential of this interface the facilitated transfer of various alkali and alkaline earth metal ions have been investigated using voltammetric methods. Additionally, the size selective transfer of tetraalkylammonium ions across this modified interface has been studied and a possible adsorption process that may be a step in the overall transfer has been identified.

12.
Neurosurgery ; 14(1): 71-3, 1984 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-6694795

RESUMEN

An unusual case of an intrasellar schwannoma radiographically simulating a pituitary tumor is reported. The literature on unusual intracranial locations of schwannomas and their possible origin is discussed.


Asunto(s)
Neurilemoma/diagnóstico por imagen , Neoplasias Hipofisarias/diagnóstico por imagen , Adulto , Angiografía Cerebral , Diagnóstico Diferencial , Humanos , Masculino , Neurilemoma/patología , Neoplasias Hipofisarias/patología , Silla Turca/diagnóstico por imagen , Neoplasias Craneales/diagnóstico por imagen , Tomografía Computarizada por Rayos X
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