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1.
BMC Public Health ; 17(1): 211, 2017 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-28212638

RESUMEN

BACKGROUND: The wide-ranging program of reforms brought about by the Health and Social Care Act (2012) in England fundamentally changed the operation of the public health system, moving responsibility for the commissioning and delivery of services from the National Health Service to locally elected councils and a new national public health agency. This paper explores the ways in which the reforms have altered public health commissioning. METHODS: We conducted multi-methods research over 33 months, incorporating national surveys of Directors of Public Health and local council elected members at two time-points, and in-depth case studies in five purposively selected geographical areas. RESULTS: Public health commissioning responsibilities have changed and become more fragmented, being split amongst a range of different organisations, most of which were newly created in 2013. There is much change in the way public health commissioning is done, in who is doing it, and in what is commissioned, since the reforms. There is wider consultation on decisions in the local council setting than in the NHS, and elected members now have a strong influence on public health prioritisation. There is more (and different) scrutiny being applied to public health contracts, and most councils have embarked on wide-ranging changes to the health improvement services they commission. Public health money is being used in different ways as councils are adapting to increasing financial constraint. CONCLUSIONS: Our findings suggest that, while some of the intended opportunities to improve population health and create a more joined-up system with clearer leadership have been achieved, fragmentation, dispersed decision-making and uncertainties regarding funding remain significant challenges. There have been profound changes in commissioning processes, with consequences for what health improvement services are ultimately commissioned. Time (and further research) will tell if any of these changes lead to improved population health outcomes and reduced health inequalities, but many of the opportunities brought about by the reforms are threatened by the continued flux in the system.


Asunto(s)
Reforma de la Atención de Salud/organización & administración , Administración de los Servicios de Salud , Medicina Estatal/organización & administración , Contratos , Inglaterra , Humanos , Liderazgo
2.
J Public Health (Oxf) ; 38(3): e201-e208, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-26487701

RESUMEN

BACKGROUND: Following the Health and Social Care Act in England, public health teams were formally transferred from the NHS to local authorities in April 2013. METHODS: Online survey of Directors of Public Health (DsPH) in local authorities in England (n = 152) to investigate their experience within local government 1 year on. Tests of association were used to explore relationships between the perceived integration and influence of public health, and changes in how the public health budget was being spent. RESULTS: The organization of and managerial arrangements for public health within councils varied. Most DsPH felt that good relationships had been established within the council, and the move had made them more able to influence priorities for health improvement, even though most felt their influence was limited. Changes in commissioning using the public health budget were already widespread and included the de-commissioning of services. CONCLUSIONS: There was a widespread feeling amongst DsPH that they had greater influence since the reforms, and that this went across the local authority and beyond. Public health's influence was most apparent when the transfer of staff to local government had gone well, when collaborative working relationships had developed, and when local partnership groups were seen as being effective.


Asunto(s)
Administración en Salud Pública , Presupuestos/organización & administración , Humanos , Gobierno Local , Innovación Organizacional , Administración en Salud Pública/economía , Administración en Salud Pública/legislación & jurisprudencia , Administración en Salud Pública/métodos , Administración en Salud Pública/estadística & datos numéricos , Medicina Estatal/legislación & jurisprudencia , Medicina Estatal/organización & administración , Medicina Estatal/estadística & datos numéricos , Encuestas y Cuestionarios , Reino Unido
3.
Heredity (Edinb) ; 94(2): 199-206, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15536485

RESUMEN

A survey of allozyme variation at 17 loci in 14 populations representing four taxonomically problematic Gran Canarian pine forest endemic taxa of Lotus (L. genistoides, L. holosericeus, L. spartioides and some taxonomically uncertain populations collected under the designation Lotus sp.) was conducted to examine their diversification and systematic relationships. All groups exhibited high values of genetic variation, although inbreeding was common within populations. Considerable among-population genetic homogeneity was detected, as inferred from low values of Gst within each of the groups. The high population sizes of these taxa and a lack of evidence for isolation by distance or genetic bottlenecks indicate that diversity has accumulated over a long period of environmental stability. The association of high genetic distances with low linear distances, and the substantial increase in the values of Gst when the taxa considered were merged in different combinations hint at an incipient (yet probably taxonomically insufficient) reproductive isolation. The genetic similarity between L. genistoides, L. holosericeus and L. spartioides, together with the different behaviour of the populations collected under the designation Lotus sp., may have important implications for the restructuring of the taxonomy of this group when the ongoing morphological studies are completed.


Asunto(s)
Variación Genética , Genética de Población , Lotus/genética , Filogenia , Islas del Atlántico , Análisis por Conglomerados , Electroforesis en Gel de Almidón , Frecuencia de los Genes , Geografía , Isoenzimas , Lotus/clasificación , Densidad de Población , Especificidad de la Especie
4.
Biodegradation ; 11(4): 263-77, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11432584

RESUMEN

Surfactants are known to increase the apparent aqueous solubility of polycyclic aromatic hydrocarbons and may thereby enhance their bioavailability. In this study the effects of four surfactants on the mineralization of phenanthrene by Pseudomonas aeruginosa in liquid culture and in soil-water suspensions was studied in batch reactors over a 15-week study period. In the absence of surfactant, liquid cultures mineralized approximately 50% of the phenanthrene added within seven weeks following a one-week lag period and an initial mineralization rate of 0.04 mg/d. Mineralization in soil-water suspensions proceeded without any measurable lag period. The initial mineralization rate was lower (0.006 mg/d), but mineralization continued to >70% over the fifteen week period. In general, the addition of very low concentrations of surfactant (<0.001%) to liquid cultures did not impact mineralization significantly. At higher surfactant concentrations (>CMC) all surfactants were seen to be inhibitory. In soil-water systems, the rate of phenanthrene mineralization was decreased even at surfactant doses that did not produce significant solubilization. In summary, none of the surfactants enhanced the mineralization of phenanthrene by P. aeruginosa in liquid culture or in soil-water suspensions. In order to rank surfactant toxicity, microbial toxicity tests were performed measuring the light output of bioluminescent bacteria as affected by the presence of surfactants. Additional toxicity testing indicated that the presence of solubilized phenanthrene increased the toxicity of the surfactant by a 100-fold suggesting that the toxicity of solubilized substrate needs also to be considered in the application of surfactant-amended remediation.


Asunto(s)
Fenantrenos/metabolismo , Pseudomonas aeruginosa/metabolismo , Suelo , Tensoactivos/farmacología , Biodegradación Ambiental/efectos de los fármacos , Citrus , Emulsiones/farmacología , Minerales , Compuestos Orgánicos , Pseudomonas aeruginosa/efectos de los fármacos , Dodecil Sulfato de Sodio/farmacología , Microbiología del Suelo
5.
Exp Brain Res ; 123(1-2): 136-44, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9835402

RESUMEN

One proposed mechanism for underpinning colour constancy is computation of the relative activity of cones within one class--cone ratios, or cone contrasts--between surfaces in a fixed scene undergoing a change in illuminant. Although there is evidence that cone ratios do determine colour appearance under many conditions, the site or sites of their computation is unknown. Here, we report that a cerebrally achromatopsic observer, MS, displayed evidence of colour constancy in asymmetric colour matching tasks and was able to discriminate changes in cone ratios for simple, but not complex scenes. We hypothesise that the site of local cone-ratio computation is therefore early in the visual system, probably retinal.


Asunto(s)
Percepción de Color/fisiología , Defectos de la Visión Cromática/fisiopatología , Sensibilidad de Contraste/fisiología , Discriminación en Psicología/fisiología , Células Fotorreceptoras Retinianas Bastones/fisiología , Humanos , Masculino , Pruebas de Visión
6.
J Neurophysiol ; 75(3): 967-85, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8867110

RESUMEN

1. We describe a four-layered neural network (Fig. 1), based on the input organization of a collision signaling neuron in the visual system of the locust, the lobula giant movement detector (LGMD). The 250 photoreceptors ("P" units) in layer 1 are excited by any change in illumination, generated when an image edge passes over them. Layers 2 and 3 incorporate both excitatory and inhibitory interactions, and layer 4 consists of a single output element, equivalent to the locust LGMD. 2. The output element of the neural network, the "LGMD", responds directionally when challenged with approaching versus receding objects, preferring approaching objects (Figs. 2-4). The time course and shape of the "LGMD" response matches that of the LGMD (Fig. 4). Directionality is maintained with objects of various sizes and approach velocities. The network is tuned to direct approach (Fig. 5). The "LGMD" shows no directional selectivity for translatory motion at a constant velocity across the "eye", but its response increases with edge velocity (Figs. 6 and 9). 3. The critical image cues for a selective response to object approach by the "LGMD" are edges that change in extent or in velocity as they move (Fig. 7). Lateral inhibition is crucial to the selectivity of the "LGMD" and the selective response is abolished or else much reduced if lateral inhibition is taken out of the network (Fig. 7). We conclude that lateral inhibition in the neuronal network for the locust LGMD also underlies the experimentally observed critical image cues for its directional response. 4. Lateral inhibition shapes the velocity tuning of the network for objects moving in the X and Y directions without approaching the eye (see Fig. 1). As an edge moves over the eye at a constant velocity, a race occurs between the excitation that is caused by edge movement and which passes down the network and the inhibition that passes laterally. Excitation must win this race for units in layer 3 to reach threshold (Fig. 8). The faster the edge moves over the eye the more units in layer 3 reach threshold and pass excitation on to the "LGMD" (Fig. 9). 5. Lateral inhibition shapes the tuning of the network for objects moving in the Z direction, toward or away from the eye (see Fig. 1). As an object approaches the eye there is a buildup of excitation in the "LGMD" throughout the movement whereas the response to object recession is often brief, particularly for high velocities. During object motion, a critical race occurs between excitation passing down the network and inhibition directed laterally, excitation must win this race for the rapid buildup in excitation in the "LGMD" as seen in the final stages of object approach (Figs. 10-12). The buildup is eliminated if, during object approach, excitation cannot win this race (as happens when the spread of inhibition laterally takes < 1 ms Fig. 13, D and E). Taking all lateral inhibition away increases the "LGMD" response to object approach, but overall directional selectivity is reduced as there is also a lot of residual network excitation following object recession (Fig. 13B). 6. Directional selectivity for rapidly approaching objects is further enhanced at the level of the "LGMD" by the timing of a feed-forward, inhibitory loop onto the "LGMD", activated when a large number of receptor units are excited in a short time. The inhibitory loop is activated at the end of object approach, truncating the excitatory "LGMD" response after approach has ceased, but at the initiation of object recession (*Fig. 2, 3, and 13). Eliminating the feed-forward, inhibitory loop prolongs the "LGMD" response to both receding and approaching objects (Fig. 13F).


Asunto(s)
Redes Neurales de la Computación , Vías Visuales/fisiología , Animales , Saltamontes , Modelos Teóricos , Programas Informáticos
7.
Perception ; 25(2): 229-41, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8733151

RESUMEN

Colour constancy is typically measured with techniques involving asymmetric matching by adjustment, in which the observer views two scenes under different illuminants and adjusts the colour of a reference patch in one to match a test patch in the other. This technique involves an unnatural task, requiring the observer to predict and adjust colour appearance under an illumination shift. Natural colour constancy is more a simple matter of determining whether a colour is the same as or different from that seen under different illumination conditions. There are also technical disadvantages to the method of matching by adjustment, particularly when used to measure colour constancy in complex scenes. Therefore, we have developed and tested a two-dimensional method of constant-stimuli, forced-choice matching paradigm for measuring colour constancy. Observers view test and reference scenes haploscopically and simultaneously, each eye maintaining separate adaptation throughout a session. On each trial, a pair of test and reference patches against multicoloured backgrounds are presented, the reference patch colours being selected from a two-dimensional grid of displayable colours around the point of perfect colour constancy. The observer's task is to respond "same" or "different". Fitting a two-dimensional Gaussian to the percentage of "different" responses yields (1) the subjective colour-constancy point, (2) the discrimination ellipse centred on this point, and (3) a map of changes in sensitivity to chromatic differences induced by the illuminant shift. The subjective colour-constancy point measured in this way shows smaller deviations from perfect colour constancy-under conditions of monocular adaptation-than previously reported; discrimination ellipses are several times larger than standard MacAdam ellipses; and chromatic sensitivity is independent of the direction of the illuminant shift, for broad distributions of background colours.


Asunto(s)
Conducta de Elección , Percepción de Color , Aprendizaje Discriminativo , Humanos , Psicofísica , Tiempo de Reacción , Umbral Sensorial
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