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1.
J Anat ; 232(5): 721-728, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29430649

RESUMO

The Anatomical Society has developed a series of learning outcomes in consultation with nursing educators delivering anatomical content to undergraduate (preregistration) nursing students. A Delphi panel methodology was adopted to select experts within the field that would recommend core anatomical content in undergraduate nursing programmes throughout the UK. Using the Anatomical Society's Core Gross Anatomy Syllabus for Medical Students as a foundation, a modified Delphi technique was used to develop discipline-specific outcomes to nursing graduates. The Delphi panel consisted of 48 individuals (n = 48) with a minimum of 3 years' experience teaching anatomy to nursing students, representing a broad spectrum of UK Higher Education Institutions. The output from this study was 64 nursing specific learning outcomes in anatomy that are applicable to all undergraduate (preregistration) programmes in the UK. The new core anatomy syllabus for Undergraduate Nursing offers a basic anatomical framework upon which nurse educators, clinical mentors and nursing students can underpin their clinical practice and knowledge. The learning outcomes presented may be used to develop anatomy teaching within an integrated nursing curriculum.


Assuntos
Anatomia/educação , Currículo/normas , Educação em Enfermagem/normas
2.
J Chem Phys ; 123(5): 054701, 2005 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-16108679

RESUMO

Applying molecular-beam methods to a nanolithographically prepared planar PdSiO2 model catalyst, we have performed a detailed study of the kinetics of CO oxidation. The model catalyst was prepared by electron-beam lithography, allowing individual control of particle size and position. The sample was structurally characterized by atomic force microscopy and scanning electron microscopy before and after reaction. In the kinetic experiments, the O-rich and CO-rich regimes were investigated systematically with respect to their transient and steady-state behaviors, both under bistable and monostable reaction conditions. Separate molecular beams were used in order to supply the reactants, allowing individual control over the reactant fluxes. The desorbing CO2 was detected by both angle-resolved and angle-integrated mass spectrometries. The experimental results were analyzed using different types of microkinetic models, including a detailed reaction-diffusion model, which takes into account the structural parameters of the catalyst as well as scattering of the reactants from the support. The model quantitatively reproduces the results as a function of the reactant fluxes and the surface temperature. Various kinetic effects observed are discussed in detail on the basis of the model. Specifically, it is shown that under conditions of limited oxygen mobility, the switching behavior between the kinetic regimes is largely driven by the surface mobility of CO.

3.
J Chem Phys ; 122(8): 84713, 2005 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-15836083

RESUMO

Combining molecular beam methods and angular resolved mass spectrometry, we have studied the angular distribution of desorbing products during CO oxidation on a planar Pd/silica supported model catalyst. The model catalyst was prepared by means of electron beam lithography, allowing individual control of particle size, position, and aspect ratio, and was characterized by atomic force microscopy and scanning electron microscopy before and after reaction. In the experiment, both oxygen and CO rich regimes were investigated using separate molecular beams for the two reactants. This allows exploration of diffusion effects of reactants on the particles and of shadowing and backscattering phenomena. A reaction-diffusion model was developed in order to extract information about local reaction rates on the surface of the catalyst nanoparticles. The model takes into account the structural parameters of the catalyst as well as the backscattering of the reactants and products from the support. It allows a quantitative description of the experimental data and provides a detailed understanding of temperature and reactant flux dependent effects. Moreover, information on the surface mobility of oxygen under steady-state reaction conditions could be obtained by comparison with the experimental results.

4.
Science ; 304(5677): 1639-44, 2004 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-15131265

RESUMO

We show that coverage fluctuations on catalyst particles can drastically alter their macroscopic catalytic behavior. Scrutinizing the occurrence of kinetic bistabilities, it is demonstrated by molecular beam experiments on model catalysts that macroscopically observable bistabilities vanish completely with decreasing particle size, as previously predicted by theory. The effect is attributed to fluctuation-induced transitions between two kinetic reaction regimes, with a transition rate controlled by both particle size and surface defects. These results suggest that fluctuation-induced effects represent a general phenomenon affecting the reaction kinetics on nanostructured surfaces.

5.
Pathobiology ; 64(5): 262-8, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9068009

RESUMO

Glycosaminoglycans (GAGs), and in particular hyaluronan, are known to play a role in tumour cell migration, invasion and metastasis. Conditioned medium from two human metastatic melanoma cell lines (Hs294T and C8161) shows potent fibroblast GAG-synthesis-stimulating activities which are active in fibroblast cultures derived from different anatomical sites. This ability is not specific to melanoma cells and is observed in several carcinoma cell lines. Initial characterisation studies have demonstrated that the GAG-stimulating activities in the medium conditioned with melanoma cells show a degree of heat and trypsin resistance. Fractionation of the conditioned medium with Amicon ultrafiltration membranes of various molecular weight cut-offs, ranging from 1 to 30 kD, resulted in a total loss of activity. Activity could be regained by recombination of the concentrated fraction with the filtrate, suggesting more than one factor to be involved in GAG stimulation, with a degree of interdependence between the individual fractions. The fraction greater than 30 kD and that less than 1 kD appear to contain the majority of the GAG-stimulating activity.


Assuntos
Glicosaminoglicanos/biossíntese , Melanoma/química , Neoplasias Cutâneas/química , Adulto , Fracionamento Químico , Pré-Escolar , Meios de Cultivo Condicionados/química , Meios de Cultivo Condicionados/farmacologia , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Masculino , Melanoma/metabolismo , Pessoa de Meia-Idade , Peso Molecular , Neoplasias Cutâneas/metabolismo , Células Tumorais Cultivadas
6.
Int J Cancer ; 52(3): 499-503, 1992 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-1399127

RESUMO

Conditioned media from cultures of human metastatic Hs294T melanoma cells contain a factor/factors that promote(s) fibroblast-mediated contraction of collagen lattices, and stimulate(s) fibroblast glycosaminoglycan (GAG) synthesis. Complete medium from melanoma cell cultures stimulated fibroblast hyaluronate synthesis 9.3-fold, and sulphated GAG synthesis 2.6-fold, as measured by 3H-glucosamine incorporation. 35SO4 incorporation into sulphated GAGS was essentially unaltered, the net result being a decrease in the degree of sulphation. Fibroblasts synthesized hyaluronate with an increased molecular weight when grown in the presence of the melanoma-cell culture medium, while the molecular weights of heparan and chondroitin sulphates remained essentially unaltered. Our results indicate that the tumour-cell-derived factor(s) stimulate(s) changes in fibroblast glycosaminoglycan synthesis, and that these changes may facilitate tumour cell invasion in vivo.


Assuntos
Glicosaminoglicanos/biossíntese , Melanoma/metabolismo , Fibroblastos/metabolismo , Humanos , Sulfatos/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Células Tumorais Cultivadas
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