On-stream analysis of particle size distributions

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The model law of Szmukler, Dawson and Daw – the next stage of a long campaign?

Except for the criminal justice system, the Mental Health Act 1983 (as amended by the MHA 2007) is the most significant Statute in England and Wales that can be used to challenge a central principle of democratic society, that of the right of an adult to self-determination. Such legislation is considered necessary as there are circumstances when it is right and appropriate to admit individuals to hospital andto treat them for their mental disorders in the absence of their consent. The need for an option of nonconsensual treatment for a physical illness is also apparent, such as in the case of unconsciousness where, for example, treatments without consent for diabetic coma or cerebral haemorrhage are likely to be lifesaving.Whether the treatment is for a mental or physical disorder, the question is the same – when is it appropriate for someone else to take a decision on behalf of another? The paper of Szmukler et al and their proposal for what they refer to as ‘fusion’ legislation goes to the heart of the issues. What are mental health and mental capacity legislation there to do? What are the principles that should underpin such legislation? What safeguards should there be? In this paper the Szmukler proposals as set out are considered from a clinical perspective in the light of studies that have examined model capacity-based mental health legislation, internationally-based principles that should guide mental health law, and other proposals such as those of the Bamford report in Northern Ireland. Whilst the approach that is proposed is non-discriminatory and ethically defensible and desirable, the difficult issue is the balancing of the need for such legislation to be both versatile and non-bureaucratic and the need for an appropriate hierarchyof safeguards that protect the vulnerable from unnecessary or inappropriate interventions. The proposed Bill put forward moves away from the thinking behind the Mental Capacity Act 2005 and is closer in its thinking to an expanded and capacity-based Mental Health Act. This requires further consideration

Analysis of crystal defects by simulation of x-ray section topographs

This thesis is concerned with the simulation of the contrast in X-ray section topographs due to the strains induced in silicon single crystals by various types of technologically relevant crystal defect. A general introduction to the field of X- ray topography is presented, illustrating that this technique is well suited to the characterisation of defect induced strain in highly perfect crystals. A review of X-ray dynamical theory is given, culminating in Takagi's equations for a crystal containing a defect. Techniques for simulating X-ray section topographs, based on Takagi's equations, are discussed. Computer simulation of section topographs has been used throughout this work to deduce the microscopic strains from the X-ray topographic images. The volume of oxygen precipitates in MCZ silicon was found to increase linearly as lnT, where T is the annealing temperature of the sample. Results suggest that the vast majority of precipitates which survive to maturity are nucleated at approximately the same time, subsequently growing at the same rate. An industrial role for simulation in conjunction with experiment is proposed, in the evaluation of the precipitate depth and the deformation parameter, C, representing the precipitate strain magnitude. The technological relevance of these two quantities is discussed. The effect of surface relaxation on the structure of images due to precipitates has been investigated. The critical depth (_z(_crit)) at which the effect of surface relaxation became negligible was found to increase linearly with lnC. Simulations have been generated for crystals containing oxygen precipitate distributions, with denuded zones. Characteristic image features have been discussed. Studies on precipitate resolvability revealed that the critical separation for two precipitates to be just resolved increases linearly as lnC. An extensive study of intrinsic gettering has been undertaken, in terms of decorated dislocations. The strain distribution due to precipitate decoration was modelled by the cylindrical inclusion model. It was shown that even for very low precipitate strains, precipitate decoration is distinguishable from the associated dislocation by section topography. Hence, an industrial role is proposed for simulation, in conjunction with experiment, in the parameterisation of the strain induced by decorated dislocations. To fully explore the use of the cylindrical inclusion model in this way, the variation in the inclusion strain magnitude was determined as a function of the precipitate strain and density, and the size of the precipitate distribution. It was found that the strain magnitude of the equivalent cylindrical inclusion must increase more rapidly relative to the precipitate deformation parameter for low-order reflections than for high-order reflections. Decorated dislocations have been shown to be resolvable by section topography even in the most dislocation-rich sihcon samples. The industrial usefulness of this characteristic is discussed. A study was made of the critical deformation parameter, C(_crit), for decorated dislocations to be just resolved, as a function of the separation, k, of the dislocations. For k greater than about 45µm, the variation of In(C(_crit) with k was linear. For smaller separations, the linearity breaks down because of the increasingly important strain contribution due to the dislocations. The strains induced by oxide films and devices in the silicon substrates onto which they are formed have been investigated. Experimental section topographs of oxide edge regions and devices on silicon have been simulated, and the visibility of the extra set of fringes found in simulations by another worker has been examined. The variation in image structure with device position on the entrance and exit surfaces has been investigated. An absolute minimum on device width detectable by section topography of lµm has been found. However, this minimum was found to depend on device-induced strain, and for values of strain characteristic of contemporary devices, the minimum detectable device width was found to be at least 3.5µm. This is above the limits set by the geometric and other constraints of the experimental technique. A thorough study has been made of the cancellation of opposing strains due to opposite edges of a device. The total distortion induced by the device was found to be minimised by reducing the device width and increasing the force per unit length, 5, along the device edges. Quantitative information has been obtained on this process. It was found that the fractional increase in lattice parameter at a fixed point, due to device-induced strain, increases linearly with S, with increasing gradient for increasing device width. It was shown that the narrower the device, the faster the relative fall-off in fractional increase in lattice parameter with increasing displacement from one edge of the device

Simulation of x-ray section topographs due to hydrogen precipitates in silicon

Computer simulation of X-ray diffraction section topographs has been used to investigate hydrogen precipitates in silicon crystals. The field of X-ray topography is reviewed, with an account of image formation and the experimental techniques used to obtain topographs. The dynamical theory, for a perfect crystal, and Takagi's theory, for an imperfect crystal, are both presented. Simulation techniques, based on numerical integration of Takagi's equations, are then discussed. A computer program is presented, which is used to simulate the experimental topographs due to hydrogen precipitates in silicon, allowing the positions of precipitates to be located. A second simulation program, to take into account the effects of surface relaxation, is constructed. Simulations with and without surface relaxation are compared, and their differences are discussed. Finally, the effect upon simulations of crystal bending is investigated. This is an important consideration, since the growth of an oxide layer onto a silicon wafer, resulting in wafer curvature, is an integral part of silicon device production technology. Possibilities for future work are discussed

The platelet laminin receptor : discovery of a 67kDA receptor for laminin on the membranes of human platelets : characterisation and isolation

Previous work on the binding of resting platelets to the basement membrane glycoprotein, laminin, has identified the Ic/IIa integrin c01aplex (CD49f/CD29), also known as VLA-6, as the receptor. There exists however, another protein with a molecular weight of 67kDa, that mediates this function on other cells. It is abundantly expressed on the membranes of breast cancer cells, where it plays a key role in both the localisation at, and penetration of vascular beds, by metastases. The objectives of this study were: * The development of a micro-titre assay similar to those used in previous studies, standardised and calibrated to characterize the adhesion of unstimulated normal human platelets to laminin-coated surfaces. * To determine the effect on adhesion of platelet activation, enzymatic surface-glycoprotein removal, antibodies to specific receptors and interaction with other adhesive proteins known to bind to platelet membranes. * To establish the in vivo relevance of the experimental findings, by the assay of adhesion of glycoprotein IIb/IIIa-deficient platelets of two patients with Glanzmann's Thrombasthenia. These studies serve d to distinguish specific binding sites for laminin from the known surface receptors of platelets. The methodology used to isolate laminin receptors from the membranes of breast carcinoma cells was then applied to platelet concentrates. Membranes were obtained by centrifuging the ultrasonic lysate of a unit of platelets. These were solubilized and passed over a laminin-Sepharose column. The bound components were eluted and identified by means of SDS-gel electrophoresis, after which a concentrate was tested for laminin binding by means of dot-blot methodology. The principle contribution of this work is the finding of a 67kDa receptor for laminin on the surface membranes of platelets. The combination of the various approaches applied to characterise the adhesion of platelets to laminin, show that this is a specific, Mg²⁺-dependent process, inhibited by Ca²⁺ and not enhanced by platelet activation. Adhesion was decreased by proteolysis with trypsin and chymotrypsin, showing that the adhesion is mediated by a surface glycoprotein. Proteolysis with the Serratia marcescens metalloprotease, which cleaves off glycoprotein lb, did not affect adhesion, proving that this well-known receptor for platelet adhesion is not involved in the adhesion. The receptors GPIV and glycocalicin were also excluded, as the presence of antibodies to these receptors had no effect. Prior incubation with fibrinogen or von Willebrand factor, which binds to specific receptors on the platelet membrane, inhibited adhesion, most likely due to spatial interference with the receptor site for laminin. The presence of the tetrapeptide recognised by the membrane receptors for many adhesive proteins, RGDS, at concentrations of up to 1mM, had no effect. The platelets of the two subjects with Glanzmann's Thrombasthenia adhered normally, definitively ruling out the involvement of GPIIb/IIIa, which is absent from these platelets. The isolation process recovered a membrane component from the laminin-Sepharose column with an elution pattern identical to that for the well characterised 67kDa receptor for laminin on the surface of breast carcinoma cells. They have the same molecular weights in both the reduced (67kDa) and non-reduced (53kDa) states. Blot identification demonstrated laminin binding by the eluate. In the last part of the work, collaborative studies using more sophisticated methodology have confirmed that platelet receptors for laminin play a role in their adhesion to living tissue. Anti-laminin Fab antibodies significantly decreased the adhesion when whole blood was perfused over isolated rabbit aortic segments. That these receptors are identical to the 67kDa receptor of breast carcinoma cells was shown by the specific, high affinity binding of antibodies directed at the carcinoma receptors to the surface of platelets when examined by flow cytometry. In addition, they inhibit platelet adhesion by 50-60% in the micro-titre assay. It is proposed that both the VLA-6 and the 67kDa receptors are required for platelet adhesion to laminin, possibly as a two-stage process, similar to the systems for adhesion to von Willebrand factor, where binding is initially to GPIb, followed by binding to GPIIb/IIIa. The possible relevance of this receptor in the pathophysiology of the metastatic process is discussed

Cognition in people with Prader-Willi syndrome: Insights into genetic influences on cognitive and social development.

We present a mini-review of cognition in Prader-Willi syndrome. Studies cited include findings on general ability (IQ), IQ correlates with family members, strengths and weaknesses in cognitive profiles in genetic subtypes, attainment in literacy and numeracy, language, comprehension, modality preferences, executive functions, and social cognition. The latter includes investigations of theory of mind, emotion recognition, face processing and knowledge of social norms. Results from research on mouse models and brain imaging studies relevant to cognition are briefly discussed. The importance of these studies to understanding and managing education and behaviour in PWS and the limitations of the studies in terms of small numbers, non-representativeness, and lack of replication is also touched upon.This is the author accepted manuscript. The final version is available from Elsevier via http://dx.doi.org/10.1016/j.neubiorev.2016.09.01

A review of the physics and ecological implications of the thermal bar circulation

AbstractFollowing recent applications of numerical modelling and remote sensing to the thermal bar phenomenon, this paper seeks to review the current state of knowledge on the effect of its circulation on lacustrine plankton ecosystems. After summarising the literature on thermal bar hydrodynamics, a thorough review is made of all plankton observations taken in the presence of a thermal bar. Two distinct plankton growth regimes are found, one with production favoured throughout the inshore region and another with a maximum in plankton biomass near the position of the thermal bar. Possible explanations for the observed distributions are then discussed, with reference to numerical modelling studies, and the scope for future study of this interdisciplinary topic is outlined

Optimal Investment in Energy Efficiency as a Problem of Growth-Rate Maximisation : Evidence and Policy Implications

Following recent developments in economic and finance theory, we formulated in a recent article the question of when and how much a consumer might optimally invest in energy efficiency as a problem of wealth-growth-rate maximisation. In this contribution, we scale up this framework to a unique dataset combining the top three wealth quantiles, and nine generations of single and terraced homes in Germany: 21% of the total building stock, altogether told. We calculate the share of dwellings over time whose consumers see incentive to retrofit, and are able to reproduce (i) the annual variation in the uptake of government subsidies, (ii) the tendency of consumers to wait out the lifetime of their current heating system, (iii) the slow diffusion of new heaters, and (iv) the propensity of consumers to shun deep retrofits. We additionally uncover new wealth effects, most notably the proclivity of richer consumers whose wealth growth faster to retrofit less, and when they do, to etrofit to shallower depths. We also compute the effects of the German government’s retrofit subsidy schemes, and the proposed carbon tax on heating, employing a counterfactual approach. We discover that wealthier consumers are in general harder to influence via policies. Tracking the effects of policies along several dimensions, we show, among other things, that the tax and subsidy schemes have effects of comparable sizes, and that their effect when combined is greater than the sum of their individual contributions. All of this has implications for policymakers: the broad conclusion of our work is that household wealth, diminishing marginal utility, and stochasticity in fuel prices can largely explain the diffusion of energy-efficiency measures. Our consequent policy recommendations include a widening of the subsidy base through a reduction or elimination of minimum investment requirements and a redefinition of the relevant thermal standards, increased subsidies for gas “renewable ready” heaters to encourage a step-wise transition towards electricity, and a push for the government itself to become a major player in the renovation market

Asylum in Ireland - a public health perspective

This report has two elements, first a review of the literature on refugees and asylum seekrs, with particular to the legal and practical situation in Ireland, and secondly a report of a survey of refugees and asylum seekers carried out in part fulfillment of the requirments for the MPH. The survey had two elements, one a quantitaitve stuy carried out in Dublin and Ennis, and the second a series of focus groups

Hex Player—a virtual musical controller

In this paper, we describe a playable musical interface for tablets and multi-touch tables. The interface is a generalized keyboard, inspired by the Thummer, and consists of an array of virtual buttons. On a generalized keyboard, any given interval always has the same shape (and therefore fingering); furthermore, the fingering is consistent over a broad range of tunings. Compared to a physical generalized keyboard, a virtual version has some advantages—notably, that the spatial location of the buttons can be transformed by shears and rotations, and their colouring can be changed to reflect their musical function in different scales. We exploit these flexibilities to facilitate the playing not just of conventional Western scales but also a wide variety of microtonal generalized diatonic scales known as moment of symmetry, or well-formed, scales. A user can choose such a scale, and the buttons are automatically arranged so their spatial height corresponds to their pitch, and buttons an octave apart are always vertically above each other. Furthermore, the most numerous scale steps run along rows, while buttons within the scale are light-coloured, and those outside are dark or removed. These features can aid beginners; for example, the chosen scale might be the diatonic, in which case the piano’s familiar white and black colouring of the seven diatonic and five chromatic notes is used, but only one scale fingering need ever be learned (unlike a piano where every key needs a different fingering). Alternatively, it can assist advanced composers and musicians seeking to explore the universe of unfamiliar microtonal scales