891 resultados para Android, anticontraffazione, app
Resumo:
ß-site AßPP cleaving enzyme 1 (BACE1) catalyses the rate-limiting step for production of amyloid-ß (Aß) peptides, involved in the pathological cascade underlying Alzheimer's disease (AD). Elevated BACE1 protein levels and activity have been reported in AD postmortem brains. Our study explored whether this was due to elevated BACE1 mRNA expression. RNA was prepared from five brain regions in three study groups: controls, individuals with AD, and another neurodegenerative disease group affected by either Parkinson's disease (PD) or dementia with Lewy bodies (DLB). BACE1 mRNA levels were measured using quantitative realtime PCR (qPCR) and analyzed by qbasePLUS using validated stably-expressed reference genes. Expression of glial and neuronal markers (glial fibrillary acidic protein (GFAP) and neuron-specific enolase (NSE), respectively) were also analyzed to quantify the changing activities of these cell populations in the tissue. BACE1 mRNA levels were significantly elevated in medial temporal and superior parietal gyri, compared to the PD/DLB and/or control groups. Superior frontal gryus BACE1 mRNA levels were significantly increased in the PD/DLB group, compared to AD and control groups. For the AD group, BACE1 mRNA changes were analyzed in the context of the reduced NSE mRNA, and strongly increased GFAP mRNA levels apparent as AD progressed (indicated by Braak stage). This analysis suggested that increased BACE1 mRNA expression in remaining neuronal cells may contribute to the increased BACE1 protein levels and activity found in brain regions affected by AD.
Resumo:
Silicone elastomer systems have previously been shown to offer potential for the sustained release of protein therapeutics. However, the general requirement for the incorporation of large amounts of release enhancing solid excipients to achieve therapeutically effective release rates from these otherwise hydrophobic polymer systems can detrimentally affect the viscosity of the precure silicone elastomer mixture and its curing characteristics. The increase in viscosity necessitates the use of higher operating pressures in manufacture, resulting in higher shear stresses that are often detrimental to the structural integrity of the incorporated protein. The addition of liquid silicones increases the initial tan delta value and the tan delta values in the early stages of curing by increasing the liquid character (G '') of the silicone elastomer system and reducing its elastic character (G'), thereby reducing the shear stress placed on the formulation during manufacture and minimizing the potential for protein degradation. However, SEM analysis has demonstrated that if the liquid character of the silicone elastomer is too high, the formulation will be unable to fill the mold during manufacture. This study demonstrates that incorporation of liquid hydroxy-terminated polydimethylsiloxanes into addition-cure silicone elastomer-covered rod formulations can both effectively lower the viscosity of the precured silicone elastomer and enhance the release rate of the model therapeutic protein bovine serum albumin. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Resumo:
Despite their widespread use, there is a paucity of information concerning the effect of storage on the rheological properties of pharmaceutical gels that contain organic and inorganic additives. Therefore, this study examined the effect of storage (1 month at either 4 or 37 degrees C) on the rheological and mechanical properties of gels composed of either hydroxypropylmethylcellulose (3-5% w/w, HPMC) or hydroxyethylcellulose (3-5% w/w, HEC) and containing or devoid of dispersed organic (tetracycline hydrochloride 2% w/w) or inorganic (iron oxide 0.1% w/w) agents. The mechanical properties were measured using texture profile analysis whereas the rheological properties were analyzed using continuous shear rheometry and modeled using the Power Law model. All formulations exhibited pseudoplastic flow with minimal thixotropy. Increasing polymer concentration (3-5% w/w) significantly increased the consistency, hardness, compressibility, and adhesiveness of the formulations due to increased polymer chain entanglement. Following storage (I month at 4 and 37 degrees C) the consistency and mechanical properties of additive free HPMC gets (but not HEC gels) increased, due to the time-dependent development of polymer chain entanglements. Incorporation of tetracycline hydrochloride significantly decreased and increased the rheological and mechanical properties of HPMC and HEC gels, respectively. Conversely, the incorporation of iron oxide did not affect these properties. Following storage, the rheological and mechanical properties of HPMC and HEC formulations were markedly compromised. This effect was greater following storage at 37 than at 4 degrees C and, additionally, greater in the presence of tetracycline hydrochloride than iron oxide. It is suggested that the loss of rheological/mechanical structure was due to chain depolymerization, facilitated by the redox properties of tetracycline hydrochloride and iron oxide. These observations have direct implications for the design and formulation of gels containing an active pharmaceutical ingredient. (c) 2005 Wiley Periodicals, Inc.
Resumo:
To formulate therapeutic proteins into polymeric devices the protein is typically in the solid state, which can be achieved by the process of freeze-drying. However, freeze-drying not only risks denaturing the protein but it can adversely affect the cure characteristics of protein-loaded silicone elastomers. This study demonstrates that a variation in the parameters of the freeze-dryer can significantly affect the residual moisture content of freeze-dried BSA, which in turn has an effect on the bulk density and flow properties of the BSA. The bulk density and flow properties of the BSA subsequently affect the cure characteristics of BSA-loaded silicone elastomers. An increase in the residual moisture content results in the freeze-dried BSA having a decreased bulk density and poor flow properties which can have a detrimental effect on the cure characteristics of a freeze-dried BSA-loaded silicone elastomer. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2012
Resumo:
Composites of recycled carbon fiber (CF) with up to 30 wt % loading with polyethylene (PE) were prepared via melt compounding. The morphology of the composites and the degree of dispersion of the CF in the PE matrix was examined using scanning electron microscopy, and revealed the CF to be highly dispersed at all loadings and strong interfacial adhesion to exist between the CF and PE. Raman and FTIR spectroscopy were used to characterize the surface chemistry and potential bonding sites of recycled CF. Both the Young's modulus and ultimate tensile stress increased with increasing CF loading, but the percentage stress at break was unchanged up to 5 wt % loading, then decreased with further successive addition of CF. The effect of CF on the elastic modulus of PE was examined using the Halpin-Tsai and modified Cox models, the former giving a better fit with the values determined experimentally. The electrical conductivity of the PE matrix was enhanced by about 11 orders of magnitude on addition of recycled CF with a percolation threshold of 7 and 15 wt % for 500-mu m and 3-mm thick samples. (c) 2007 Wiley Periodicals, Inc.
Resumo:
Rare mutations in AßPP, PSEN1, and PSEN2 cause uncommon early onset forms of Alzheimer's disease (AD), and common variants in MAPT are associated with risk of other neurodegenerative disorders. We sought to establish whether common genetic variation in these genes confer risk to the common form of AD which occurs later in life (>65 years). We therefore tested single-nucleotide polymorphisms at these loci for association with late-onset AD (LOAD) in a large case-control sample consisting of 3,940 cases and 13,373 controls. Single-marker analysis did not identify any variants that reached genome-wide significance, a result which is supported by other recent genome-wide association studies. However, we did observe a significant association at the MAPT locus using a gene-wide approach (p = 0.009). We also observed suggestive association between AD and the marker rs9468, which defines the H1 haplotype, an extended haplotype that spans the MAPT gene and has previously been implicated in other neurodegenerative disorders including Parkinson's disease, progressive supranuclear palsy, and corticobasal degeneration. In summary common variants at AßPP, PSEN1, and PSEN2 and MAPT are unlikely to make strong contributions to susceptibility for LOAD. However, the gene-wide effect observed at MAPT indicates a possible contribution to disease risk which requires further study.
Resumo:
We characterized hydrogels, prepared from aqueous blends of poly(methyl vinyl ether-co-maleic acid) (PMVE/MA) and poly(ethylene glycol) (PEG 10,000 Daltons) containing a pore-forming agent (sodium bicarbonate, NaHCO ). Increase in NaHCO content increased the equilibrium water content (EWC) and average molecular weight between crosslinks (M ) of hydrogels. For example, the %EWC was 731, 860, 1109, and 7536% and the M was 8.26, 31.64, 30.04, and 3010.00 × 10 g/mol for hydrogels prepared from aqueous blends containing 0, 1, 2, and 5% w/w of NaHCO , respectively. Increase in NaHCO content also resulted in increased permeation of insulin. After 24 h, percentage permeation was 0.94, 3.68, and 25.71% across hydrogel membranes prepared from aqueous blends containing 0, 2, and 5% w/w of NaHCO , respectively. Hydrogels containing the pore-forming agent were fabricated into microneedles (MNs) for transdermal drug delivery applications by integrating the MNs with insulin-loaded patches. It was observed that the mean amount of insulin permeating across neonatal porcine skin in vitro was 20.62% and 52.48% from hydrogel MNs prepared from aqueous blends containing 0 and 5% w/w of NaHCO . We believe that these pore-forming hydrogels are likely to prove extremely useful for applications in transdermal drug delivery of biomolecules. © 2012 Wiley Periodicals, Inc.
Resumo:
The two critical forms of dementia are Alzheimer's disease (AD) and vascular dementia (VD).The alterations of Ca2+/calmodulin/CaMKII/CaV1.2 signaling in AD and VD have not been well elucidated. Here we have demonstrated changes in the levels of CaV1.2, calmodulin, p-CaMKII, p-CREB and BDNF proteins by Western blot analysis and the co-localization of p-CaMKII/CaV1.2 by double-labeling immunofluorescence in the hippocampus of APP/PS1 mice and VD gerbils. Additionally, expression of these proteins and intracellular calcium levels were examined in cultured neurons treated with Aß1–42. The expression of CaV1.2 protein was increased in VD gerbils and in cultured neurons but decreased in APP/PS1 mice; the expression of calmodulin protein was increased in APP/PS1 mice and VD gerbils; levels of p-CaMKII, p-CREB and BDNF proteins were decreased in AD and VD models. The number of neurons in which p-CaMKII and CaV1.2 were co-localized, was decreased in the CA1 and CA3 regions in two models. Intracellular calcium was increased in the cultured neurons treated with Aß1–42. Collectively, our results suggest that the alterations in CaV1.2, calmodulin, p-CaMKII, p-CREB and BDNF can be reflective of an involvement in the impairment in memory and cognition in AD and VD models.
Resumo:
Summary: We present a new R package, diveRsity, for the calculation of various diversity statistics, including common diversity partitioning statistics (?, G) and population differentiation statistics (D, GST ', ? test for population heterogeneity), among others. The package calculates these estimators along with their respective bootstrapped confidence intervals for loci, sample population pairwise and global levels. Various plotting tools are also provided for a visual evaluation of estimated values, allowing users to critically assess the validity and significance of statistical tests from a biological perspective. diveRsity has a set of unique features, which facilitate the use of an informed framework for assessing the validity of the use of traditional F-statistics for the inference of demography, with reference to specific marker types, particularly focusing on highly polymorphic microsatellite loci. However, the package can be readily used for other co-dominant marker types (e.g. allozymes, SNPs). Detailed examples of usage and descriptions of package capabilities are provided. The examples demonstrate useful strategies for the exploration of data and interpretation of results generated by diveRsity. Additional online resources for the package are also described, including a GUI web app version intended for those with more limited experience using R for statistical analysis. © 2013 British Ecological Society.
Resumo:
Background: Clinical supervision takes place once the newly qualified nurse is employed in clinical practice. However, often the variety and diversity of nursing jobs can result in a hit and miss delivery of supervision training. By introducing training uniformly at undergraduate stage a more seamless transition may occur (McColgan K, Rice C. 2012).
There is an increased interest in higher education in the use of online learning resources for students. As part completion of a DNP an App. for training students in clinical supervision was developed.
Aim: The creation of a clinical supervision training App. for use in undergraduate nursing.
Objectives:
•To develop a teaching tool that is up to date, current and easily accessible to students.
•To introduce supervision training for undergraduate nursing students
•To motivate the undergraduate nursing student to identify examples from their clinical experience to encourage change and promote professional development.
Approach:
Stage 1
In 2010/11 informal inquiries with senior nurses regarding the introduction of supervision training in undergraduate nursing
Stage 2
A review of UK supervision training.
Stage 3
Template production of teaching tool.
Stage 4
Collaboration with a computer technician to transfer multimedia outputs onto an App.
Stage 5
App. piloted with lecturers (n=4) and post registration students (n=20).
Stage 6
Minor alterations made to App. design template
Stage 7
App. included in an experimental study looking at online learning versus blended learning June 2013 (n=61, n=63)
Conclusion: A collaborative approach to the development of any educational programme is essential to ensure the success of the final teaching product (McCutcheon 2013). The end result is that this App. could be:
•Made available to nurses in the UK.
•Adapted to suit other healthcare professionals and students.
•Used as a prototype for other healthcare related subjects.
McColgan K., Rice C. (2012) An online training resource for clinical supervision. Nursing Standard, 26(24) 35-39.
McCutcheon K. (2013) Development of a multi-media book for clinical supervision training in an undergraduate nursing programme. Journal of Nursing Education and Practice, 3(5) 31-38.
Resumo:
The effects of addition of reinforcing carbon nanotubes (CNTs) into hydrogenated nitrile-butadiene rubber (HNBR) matrix on the mechanical, dynamic viscoelastic, and permeability properties were studied in this investigation. Different techniques of incorporating nanotubes in HNBR were investigated in this research. The techniques considered were more suitable for industrial preparation of rubber composites. The nanotubes were modified with different surfactants and dispersion agents to improve the compatibility and adhesion of nanotubes on the HNBR matrix. The effects of the surface modification of the nanotubes on various properties were examined in detail. The amount of CNTs was varied from 2.5 to 10 phr in different formulations prepared to identify the optimum CNT levels. A detailed analysis was made to investigate the morphological structure and mechanical behavior at room temperature. The viscoelastic behavior of the nanotube filler elastomer was studied by dynamic mechanical thermal analysis (DMTA). Morphological analysis indicated a very good dispersion of the CNTs for a low nanotube loading of 3.5 phr. A significant improvement in the mechanical properties was observed with the addition of nanotubes. DMTA studies revealed an increase in the storage modulus and a reduction in the glass-transition temperature after the incorporation of the nanotubes. Further, the HNBR/CNT nanocomposites were subjected to permeability studies. The studies showed a significant reduction in the permeability of nitrogen gas. Copyright © 2011 Wiley Periodicals, Inc.
Resumo:
Data processing is an essential part of Acoustic Doppler Profiler (ADP) surveys, which have become the standard tool in assessing flow characteristics at tidal power development sites. In most cases, further processing beyond the capabilities of the manufacturer provided software tools is required. These additional tasks are often implemented by every user in mathematical toolboxes like MATLAB, Octave or Python. This requires the transfer of the data from one system to another and thus increases the possibility of errors. The application of dedicated tools for visualisation of flow or geographic data is also often beneficial and a wide range of tools are freely available, though again problems arise from the necessity of transferring the data. Furthermore, almost exclusively PCs are supported directly by the ADP manufacturers, whereas small computing solutions like tablet computers, often running Android or Linux operating systems, seem better suited for online monitoring or data acquisition in field conditions. While many manufacturers offer support for developers, any solution is limited to a single device of a single manufacturer. A common data format for all ADP data would allow development of applications and quicker distribution of new post processing methodologies across the industry.
Resumo:
The structure and properties of melt mixed high-density polyethylene/multi-walled carbon nanotube (HDPE/MWCNT) composites processed by compression molding and blown film extrusion were investigated to assess the influence of processing route on properties. The addition of MWCNTs leads to a more elastic response during deformations that result in a more uniform thick-ness distribution in the blown films. Blown film composites exhibit better mechanical properties due to the enhanced orientation and disentanglement of MWCNTs. At a blow up ratio (BUR) of 3 the breaking strength and elongation in the machine direction of the film with 4 wt % MWCNTs are 239% and 1054% higher than those of compression molded (CM) samples. Resistivity of the composite films increases significantly with increasing BURs due to the destruction of conductive pathways. These pathways can be recovered partially using an appropriate annealing process. At 8 wt % MWCNTs, there is a sufficient density of nanotubes to maintain a robust network even at high BURs.
Resumo:
The Belfast Soundwalks project, led by Professor Pedro Rebelo and co-ordinated by Dr Sarah Bass (Sonic Arts Research Centre) in collaboration with Belfast City Council (BCC), aims to use sonic art to engage the public through the development of a locative mobile phone app. Targeting both tourists and citizens of the city, this project aims to sonically enhance the experience of a number of areas of the city, including destinations that may not traditionally be accessed as attractions by visitors and/or disregarded or undervalued by local residents. The project will bring together a number of sonic artists/composers who will create approximately ten soundwalks around the city, while liaising with BCC to distribute the resulting app to the public in line with their tourism and cultural strategy. The project is centred on the development of smart phone apps which provide unique listening experiences associated with key places in the city. The user’s location in the city is tracked through GPS which triggers sound materials ranging from speech to environmental sound and abstract imagined sound worlds. Additionally, local community groups will be consulted in order to evaluate and reflect upon the effectiveness of the soundwalks.
The project builds on the success of the Literary Belfast app and aims to further strengthen links between Queen’s University Belfast and Belfast City Council through facilitating the dissemination of an art form not widely experienced by the general public. Through the newly created Institute for Collaborative Research in the Humanities, directed by Professor John Thompson we are articulating this project with Queen’s consortium partners, Newcastle University and Durham University.
“The Arts and Humanities Research Council (AHRC) funds world-class, independent researchers in a wide range of subjects: ancient history, modern dance, archaeology, digital content, philosophy, English literature, design, the creative and performing arts, and much more. This financial year the AHRC will spend approximately £98m to fund research and postgraduate training in collaboration with a number of partners. The quality and range of research supported by this investment of public funds not only provides social and cultural benefits but also contributes to the economic success of the UK. For further information on the AHRC, please go to: www.ahrc.ac.uk”.