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Trends in long-term prescribing of dependence forming medicines
Using patient-level primary care data to estimate the extent to which antidepressant medicines are prescribed to people continuously for long periods of time.
Aim
This descriptive research used patient-level primary care data to estimate the extent to which antidepressant medicines are prescribed to people continuously for long periods of time. The study also drew on survey data and data on the number of prescriptions dispensed.
Findings
- The number of antidepressant prescriptions dispensed each year in England doubled between 2008 and 2018
- Survey data show that the proportion of adults reporting use of antidepressants in the past year increased in the 1990s, and again between 2007 and 2014
- The average length of time that antidepressants are continuously prescribed to people for has increased over time.
- Some types of antidepressants (for example, tricyclics and other antidepressants) tend to be prescribed for longer periods than other types (such as SSRIs).
- In 2014, one in twelve prescribing periods for tricyclics and other antidepressants lasted for three years or more
Methods
The analyses in this report are descriptive and show the overall prevalence of long-term prescribing in each year.
We used a sample of around 50,000 patients prescribed at least one antidepressant medicine between 2000 and 2017. This was drawn from the Clinical Practice Research Datalink (CPRD). The CPRD contains data about prescriptions issued by GPs (including the length and size of prescription) and characteristics of the patients prescribed to (such as their age, sex, and area where they live). Medicines were grouped for analysis into: tricyclics, selective serotonin reuptake inhibitors (SSRIs), and other ADMs. The length of individual prescriptions and continuous prescribing periods were derived using information on consultation dates, the quantity of tablets prescribed, and the numeric daily dose
Optimizing the Drude-Lorentz model for material permittivity: Examples for semiconductors
Approximating the frequency dispersion of the permittivity of materials with
simple analytical functions is of fundamental importance for understanding and
modeling their optical properties. Quite generally, the permittivity can be
treated in the complex frequency plane as an analytic function having a
countable number of simple poles which determine the dispersion of the
permittivity, with the pole weights corresponding to generalized conductivities
of the medium at these resonances. The resulting Drude-Lorentz model separates
the poles at frequencies with zero real part (Ohm's law and Drude poles) from
poles with finite real part (Lorentz poles). To find the parameters of such an
analytic function, we minimize the error weighted deviation between the model
and measured values of the permittivity. We show examples of such optimizations
for various semiconductors (Si, GaAs and Ge), for different frequency ranges
and up to five pairs of Lorentz poles accounted for in the model.Comment: arXiv admin note: substantial text overlap with arXiv:1612.0692
The bactericidal activity of glutaraldehyde-impregnated polyurethane
Although glutaraldehyde is known to be bactericidal in solution, its potential use to create novel antibacterial polymers suitable for use in healthcare environments has not been evaluated. Here, novel materials were prepared in which glutaraldehyde was either incorporated into polyurethane using a simple “swell-encapsulation-shrink” method (hereafter referred to as “glutaraldehyde-impregnated polyurethane”), or simply applied to the polymer surface (hereafter referred to as “glutaraldehyde-coated polyurethane”). The antibacterial activity of glutaraldehyde-impregnated and glutaraldehyde-coated polyurethane samples was tested against Escherichia coli and Staphylococcus aureus. Glutaraldehyde-impregnated polyurethane resulted in a 99.9% reduction in the numbers of E. coli within 2 h and a similar reduction of S. aureus within 1 h, whereas only a minimal reduction in bacterial numbers was observed when the biocide was bound to the polymer surface. After 15 days, however, the bactericidal activity of the impregnated material was substantially reduced presumably due to polymerization of glutaraldehyde. Thus, although glutaraldehyde retains antibacterial activity when impregnated into polyurethane, activity is not maintained for extended periods of time. Future work should examine the potential of chemical modification of glutaraldehyde and/or polyurethane to improve the useful lifespan of this novel antibacterial polymer
Optimizing the Drude-Lorentz model for material permittivity: Method, program, and examples for gold, silver, and copper
Approximating the frequency dispersion of the permittivity of materials with simple analytical functions is of fundamental importance for understanding and modeling the optical response of materials and resulting structures. In the generalized Drude-Lorentz model, the permittivity is described in the complex frequency plane by a number of simple poles having complex weights, which is a physically relevant and mathematically simple approach: By construction, it respects causality, represents physical resonances of the material, and can be implemented easily in numerical simulations. We report here an efficient method of optimizing the fit of measured data with the Drude-Lorentz model having an arbitrary number of poles. We show examples of such optimizations for gold, silver, and copper, for different frequency ranges and up to four pairs of Lorentz poles taken into account. We also provide a program implementing the method for general use
White light-activated antimicrobial surfaces: effect of nanoparticles type on activity
Toluidine blue O (TBO) dye together with either silver (Ag) nanoparticles (NPs), gold (Au) NPs, or a mixture of Ag and Au NPs (Mix Ag–Au NPs) were incorporated into polyurethane to make antimicrobial surfaces using a swell-encapsulation-shrink process. Antimicrobial testing against Escherichia coli showed that inclusion of the NPs significantly enhanced the antimicrobial activities of the TBO polyurethane samples. In particular, samples containing Ag NPs exhibited potent antimicrobial activity under white light and surprisingly, also in the dark. The numbers of viable bacteria decreased below the detection limit on the TBO/Ag NPs incorporated samples within 3 h and 24 h under white light and dark conditions. A mechanistic study using furfuryl alcohol indicated that the enhanced photobactericidal activity was most likely due to a type I photochemical reaction. To the best of our knowledge, this is the first report of an antimicrobial surface comprised of a combination of Ag NPs and a light activated agent to provide a dual kill mechanism. These surfaces are promising candidates for use in healthcare environments to reduce the incidence of hospital-acquired infections
Coronary heart disease in Indian Asians.
The Indian Asian population accounts for a fifth of all global deaths from coronary heart disease (CHD). CHD deaths on the Indian subcontinent have doubled since 1990, and are predicted to rise a further 50% by 2030. Reasons underlying the increased CHD mortality among Indian Asians remain unknown. Although conventional cardiovascular risk factors contribute to CHD in Indian Asians as in other populations, these do not account for their increased risk. Type-2 diabetes, insulin resistance and related metabolic disturbances are more prevalent amongst Indian Asians than Europeans, and have been proposed as major determinants of higher CHD risk among Indian Asians. However, this view is not supported by prospective data. Genome-wide association studies have not identified differences in allele frequencies or effect sizes in known loci to explain the increased CHD risk in Indian Asians. Limited knowledge of mechanisms underlying higher CHD risk amongst Indian Asians presents a major obstacle to reducing the burden of CHD in this population. Systems biology approaches such as genomics, epigenomics, metabolomics and transcriptomics, provide a non-biased approach for discovery of novel biomarkers and disease pathways underlying CHD. Incorporation of these omic approaches in prospective Indian Asian cohorts such as the London Life Sciences Population Study (LOLIPOP) provide an exciting opportunity for the identification of new risk factors underlying CHD in this high risk population
Dermatoglyphic patterns in type 2 diabetes mellitus
Dermatoglyphics is the study of epidermal ridge patterns on the palm, fingers, sole and toes. They are genetically determined and are useful in diagnosis of various genetic diseases like Diabetes mellitus. There are three types of fingerprint patterns: Arches, loops and whorls. Finger prints of both hands are not same and they persist throughout life unless there is damage to the dermis. The patterns of fingertip patterns begin to form around the 13th week of intrauterine life. These patterns are inherited in from genetic makeup of the parents but the inheritance is not purely Mendelian. They get modified during the first few weeks of the intrauterine life due to pressure on the finger pads and on the palms.Keywords: Epidermal, Dermatoglyphics, Genetic, Arche
Nonlinear digital storytelling through multiple perspectives.
There lies a big distinction between gaming and films in terms of interactivity, however the gap is being bridged with experimental pieces. The advances have been made on the gaming side with stories being incorporated into games through the usage of video clips. The web, due to its vastness of interactivity, has also begun to use video in experimental ways.
My thesis will apply the interactive principles of gaming to digital video to create a unique user experience, where the users choose various perspectives to investigate through the film. The user will have to watch most of the perspectives to understand the story. With research into DVD authoring, I also intend to have the DVD randomly making choices to create a linear format of the movie. This ensures that the user sees the same movie but through different perspectives and paths every time they watch the movie.
When someone buys a DVD they tend to watch it several times. If there are a variety of options for viewing provided for them, they will spend more time with the DVD and get a different experience of the story upon every watch. This makes the entertainment value of the product higher thus increasing its marketing potential
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