983 resultados para C. Grandis L. Osbeck


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Using ion carbon beams generated by high intensity short pulse lasers we perform measurements of single shot mean charge equilibration in cold or isochorically heated solid density aluminum matter. We demonstrate that plasma effects in such matter heated up to 1 eV do not significantly impact the equilibration of carbon ions with energies 0.045-0.5 MeV/nucleon. Furthermore, these measurements allow for a first evaluation of semiempirical formulas or ab initio models that are being used to predict the mean of the equilibrium charge state distribution for light ions passing through warm dense matter.

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This study investigates the production of organic fertilizer using Anaerobic Digestate (as a nutrient source) and limestone powder as the raw materials. A two-level factorial experimental design was used to determine the influence of process variables on the nutrient homogeneity within the granules. Increasing the liquid-to-solid ratio during granulation resulted in increased granule nutrient homogeneity. Increasing the processing time and the impeller speed were also found to increase the nutrient homogeneity. In terms of nutrients release into deionized water, the granules effectively released both potassium and phosphate into solution. © 2012 Elsevier Ltd.

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PURPOSE. To determine whether internal limiting membrane (ILM) peeling is effective and cost effective compared with no peeling in patients with idiopathic stage 2 or 3 full-thickness maculay hole (FTMH). METHODS. This was a pragmatic multicenter randomized controlled trial. Eligible participants from nine centers were randomized to ILM peeling or no peeling (1:1 ratio) in addition to phacovitrectomy, including detachment and removal of the posterior hyaloid and gas tamponade. The primary outcome was distance visual acuity (VA) at 6 months after surgery. Secondary outcomes included hole closure, distance VA at other time points, near VA, contrast sensitivity, reading speed, reoperations, complications, resource use, and participant-reported health status, visual function, and costs. RESULTS. Of 141 participants randomized in nine centers, 127 (90%) completed the 6-month follow-up. Nonstatistically significant differences in distance visual acuity at 6 months were found between groups (mean difference, 4.8; 95% confidence interval [CI], -0.3 to 9.8; P = 0.063). There was a significantly higher rate of hole closure in the ILM-peel group (56 [84%] vs. 31 [48%]) at 1 month (odds ratio [OR], 6.23; 95% CI, 2.64-14.73; P <0.001) with fewer reoperations (8 [12%] vs. 31 [48%]) performed by 6 months (OR, 0.14; 95% CI, 0.05- 0.34; P <0.001). Peeling the ILM is likely to be cost effective. CONCLUSIONS. There was no evidence of a difference in distance VA after the ILM peeling and no-ILM peeling techniques. An important benefit in favor of no ILM peeling was ruled out. Given the higher anatomic closure and lower reoperation rates in the ILM-peel group, ILM peeling seems to be the treatment of choice for idiopathic stage 2 to 3 FTMH. © 2011 The Association for Research in Vision and Ophthalmology, Inc.

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Voltage-gated sodium channels (VGSCs) play a crucial role in epilepsy. The expressions of different VGSCs subtypes are varied in diverse animal models of epilepsy that may reflect their multiple phenotypes or the complexity of the mechanisms of epilepsy. In a previous study, we reported that NaV1.1 and NaV1.3 were up-regulated in the hippocampus of the spontaneously epileptic rat (SER). In this study, we further analyzed both the expression and distribution of the typical VGSC subtypes NaV1.1, NaV1.2, NaV1.3 and NaV1.6 in the hippocampus and in the cortex of the temporal lobe of two genetic epileptic animal models: the SER and the tremor rat (TRM). The expressions of calmodulin (CaM) and calmodulin-dependent protein kinase II (CaMKII) were also analyzed with the purpose of assessing the effect of the CaM/CaMKII pathway in these two models of epilepsy. Increased expression of the four VGSC subtypes and CaM, accompanied by a decrease in CaMKII was observed in the hippocampus of both the SERs and the TRM rats. However, the changes observed in the expression of VGSC subtypes and CaM were decreased with an elevated CaMKII in the cortex of their temporal lobes. Double-labeled immunofluorescence data suggested that in SERs and TRM rats, the four subtypes of the VGSC proteins were present throughout the CA1, CA3 and dentate gyrus regions of the hippocampus and temporal lobe cortex and these were co-localized in neurons with CaM. These data represent the first evidence of abnormal changes in expression of four VGSC subtypes (NaV1.1, NaV1.2, NaV1.3 and NaV1.6) and CaM/CaMKII in the hippocampus and temporal lobe cortex of SERs and TRM rats. These changes may be involved in the generation of epileptiform activity and underlie the observed seizure phenotype in these rat models of genetic epilepsy.

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Parkinson's disease (PD) is a chronic, progressive, degenerative disorder of the nervous system, causing substantial morbidity and has the capacity to shorten life. People with PD and their families can find the disease devastating. Nevertheless, this population of patients is not usually considered a group to be supported by palliative care specialists. But the nature of the illness and the challenges of managing its many physical and psychological effects raises questions about the potential benefits of a palliative care approach. The purpose of this project was to describe the experience of PD and consider the relevance of palliative care for this population. Semi-structured interviews were conducted with eight people with PD, 21 family caregivers and six health professionals. Five themes were developed from the data analysis: (1) emotional impact of diagnosis; (2) staying connected; (3) enduring financial hardship; (4) managing physical challenges; and (5) finding help for advanced stages. These data revealed that people with PD and family caregivers are confronted with similar issues to people with typical palliative care diagnoses, such as advanced cancer, and that a palliative approach may be helpful in the care of people with PD and their families.

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Objectives: To assess whether open angle glaucoma (OAG) screening meets the UK National Screening Committee criteria, to compare screening strategies with case finding, to estimate test parameters, to model estimates of cost and cost-effectiveness, and to identify areas for future research. Data sources: Major electronic databases were searched up to December 2005. Review methods: Screening strategies were developed by wide consultation. Markov submodels were developed to represent screening strategies. Parameter estimates were determined by systematic reviews of epidemiology, economic evaluations of screening, and effectiveness (test accuracy, screening and treatment). Tailored highly sensitive electronic searches were undertaken. Results: Most potential screening tests reviewed had an estimated specificity of 85% or higher. No test was clearly most accurate, with only a few, heterogeneous studies for each test. No randomised controlled trials (RCTs) of screening were identified. Based on two treatment RCTs, early treatment reduces the risk of progression. Extrapolating from this, and assuming accelerated progression with advancing disease severity, without treatment the mean time to blindness in at least one eye was approximately 23 years, compared to 35 years with treatment. Prevalence would have to be about 3-4% in 40 year olds with a screening interval of 10 years to approach cost-effectiveness. It is predicted that screening might be cost-effective in a 50-year-old cohort at a prevalence of 4% with a 10-year screening interval. General population screening at any age, thus, appears not to be cost-effective. Selective screening of groups with higher prevalence (family history, black ethnicity) might be worthwhile, although this would only cover 6% of the population. Extension to include other at-risk cohorts (e.g. myopia and diabetes) would include 37% of the general population, but the prevalence is then too low for screening to be considered cost-effective. Screening using a test with initial automated classification followed by assessment by a specialised optometrist, for test positives, was more cost-effective than initial specialised optometric assessment. The cost-effectiveness of the screening programme was highly sensitive to the perspective on costs (NHS or societal). In the base-case model, the NHS costs of visual impairment were estimated as £669. If annual societal costs were £8800, then screening might be considered cost-effective for a 40-year-old cohort with 1% OAG prevalence assuming a willingness to pay of £30,000 per quality-adjusted life-year. Of lesser importance were changes to estimates of attendance for sight tests, incidence of OAG, rate of progression and utility values for each stage of OAG severity. Cost-effectiveness was not particularly sensitive to the accuracy of screening tests within the ranges observed. However, a highly specific test is required to reduce large numbers of false-positive referrals. The findings that population screening is unlikely to be cost-effective are based on an economic model whose parameter estimates have considerable uncertainty, in particular, if rate of progression and/or costs of visual impairment are higher than estimated then screening could be cost-effective. Conclusions: While population screening is not cost-effective, the targeted screening of high-risk groups may be. Procedures for identifying those at risk, for quality assuring the programme, as well as adequate service provision for those screened positive would all be needed. Glaucoma detection can be improved by increasing attendance for eye examination, and improving the performance of current testing by either refining practice or adding in a technology-based first assessment, the latter being the more cost-effective option. This has implications for any future organisational changes in community eye-care services. Further research should aim to develop and provide quality data to populate the economic model, by conducting a feasibility study of interventions to improve detection, by obtaining further data on costs of blindness, risk of progression and health outcomes, and by conducting an RCT of interventions to improve the uptake of glaucoma testing. © Queen's Printer and Controller of HMSO 2007. All rights reserved.

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BACKGROUND: Glaucoma is the leading cause of irreversible blindness. Although primary open-angle glaucoma is more common, primary angle-closure glaucoma (PACG) is more likely to result in irreversible blindness. By 2020, 5·3 million people worldwide will be blind because of PACG. The current standard care for PACG is a stepped approach of a combination of laser iridotomy surgery (to open the drainage angle) and medical treatment (to reduce intraocular pressure). If these treatments fail, glaucoma surgery (eg, trabeculectomy) is indicated. It has been proposed that, because the lens of the eye plays a major role in the mechanisms leading to PACG, early clear lens extraction will improve glaucoma control by opening the drainage angle. This procedure might reduce the need for drugs and glaucoma surgery, maintain good visual acuity, and improve quality of life compared with standard care.EAGLE aims to evaluate whether early lens extraction improves patient-reported, clinical outcomes, and cost-effectiveness, compared with standard care.

METHODS/DESIGN: EAGLE is a multicentre pragmatic randomized trial. All people presenting to the recruitment centres in the UK and east Asia with newly diagnosed PACG and who are at least 50 years old are eligible.The primary outcomes are EQ-5D, intraocular pressure, and incremental cost per quality adjusted life year (QALY) gained. Other outcomes are: vision and glaucoma-specific patient-reported outcomes, visual acuity, visual field, angle closure, number of medications, additional surgery (e.g., trabeculectomy), costs to the health services and patients, and adverse events.A single main analysis will be done at the end of the trial, after three years of follow-up. The analysis will be based on all participants as randomized (intention to treat). 400 participants (200 in each group) will be recruited, to have 90% power at 5% significance level to detect a difference in EQ-5D score between the two groups of 0·05, and a mean difference in intraocular pressure of 1·75 mm Hg. The study will have 80% power to detect a difference of 15% in the glaucoma surgery rate.

TRIAL REGISTRATION: ISRCTN44464607.

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Background: Evidence for non-steroidal anti-inflammatory drugs (NSAIDs) preventing head and neck cancer (HNC) is inconclusive; however, there is some suggestion that aspirin may exert a protective effect.

Methods: Using data from the United States National Cancer Institute Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial, we examined the association between aspirin and ibuprofen use and HNC.

Results: Regular aspirin use was associated with a significant 22% reduction in HNC risk. No association was observed with regular ibuprofen use.

Conclusion: Aspirin may have potential as a chemopreventive agent for HNC, but further investigation is warranted.

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This study examines the influence of social ecological risks within the domains of parenting, family environment, and community in the prediction of educational outcomes for 770 adolescents (49% boys, 51% girls, M = 13.6 years, SD = 2.0) living in a setting of protracted political conflict, specifically working class areas of Belfast, Northern Ireland. Controlling for religious community, age, and gender, youths' lower academic achievement was associated with family environments characterized by high conflict and low cohesion. School behaviour problems were related to greater exposure to community violence, or sectarian and nonsectarian antisocial behaviour. Youths' expectations about educational attainment were undermined by conflict in the family environment and antisocial behaviour in the community, as well as parenting low in warmth and behavioural control. Findings underscore the importance of considering family and community contributions to youths' educational outcomes. Suggestions regarding targeted interventions toward promoting resilience are discussed, such as assessing both child and family functioning, developing multidimensional interventions for parents, and building community partnerships, among others.

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A systematic review was conducted of studies evaluating the effects of interventions aimed at reducing ethnic prejudice and discrimination in young children. Articles published between 1980 and 2010 and including children of 8 years and under were identified, harvested, and assessed for quality, both for the exposure/program as well as for the evaluation. In total, 32 studies (14 contact and 18 media or instruction) yielded 62 effects on attitudes and 59 effects on peer relations. An overall count of the positive (40%), non-significant (50%), and negative effects (10%) indicate a mixed picture. Overall, more attitude effects (55%) than peer relations effects (25%) were positive, and media/instruction (47%) was more successful than contact (36%). Most of the effects were observed with children from a majority ethnicity: 67% of the attitude effects were positive, and media/instruction and contact were equally effective at delivering these. Few differences were found as a function of the quality of the exposure and evaluation, but differences were found depending on the context of exposure (naturally occurring or experimental manipulation) and research design (random assignment or self-selection). In conclusion, the findings were more mixed than expected, though sufficiently strong studies exist to provide lessons for future research.


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A mechanism of dual enlargement of gold nanoparticles (AuNPs) comprising two steps is described. In the first step, the AuNPs are enlarged by depositing Au atoms on their crystalline faces. In this process, the particles are not only enlarged but they are also observed to multiply: new Au nuclei are formed by the budding and division of the enlarged particles. In the second step, a silver enhancement is subsequently performed by the deposition of silver atoms on the enlarged and newly formed AuNPs to generate bimetallic Au@Ag core-shell structures. The dual nanocatalysis greatly enhances the electron density of the nanostructures, leading to a stronger intensity for colorimetric discrimination as well as better sensitivity for quantitative measurement. Based on this, a simple scanometric assay for the on-slide detection of the food-born pathogen Campylobacter jejuni is developed. After capturing the target bacteria, gold-tagged immunoprobes are added to create a signal on a solid substrate. The signal is then amplified by the dual enlargement process, resulting in a strong color intensity that can easily be recognized by the unaided eye, or measured by an inexpensive flatbed scanner. In this paper, dual nanocatalysis is reported for the first time. It provides a valuable mechanistic insight into the development of a simple and cost-effective detection format.

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This paper describes the design, implementation, and characterization of a new type of passive power splitting and combining structure for use in a differential four-way power-combining amplifier operating at E-band. In order to achieve lowest insertion loss, input and output coils inductances are resonated with shunt capacitances. Simple C-L-C and L-C networks are proposed in order to compensate inductive loading due to routing line that would otherwise introduce mismatch and increase loss. Across 78-86 GHz band, measured insertion loss is about 7 dB. Measured return losses are >10 dB from 73 GHz to 94 GHz at the input port and >9 dB from 60 GHz to 94 GHz at the output port. When integrated with driver and power amplifier cells, the simulated complete circuit exhibits 18.2 dB gain and 20.3 dBm saturated output power.

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The Runt domain transcription factor, RUNX3, has been shown to be a tumor suppressor in a variety of cancers including gastric, colon and breast cancer. Interestingly, an oncogenic role for RUNX3 has also been suggested in basal cell carcinoma and head and neck cancer. Here, we explore the role of RUNX3 in ovarian cancer.

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More than 200 known diseases are transmitted via foods or food products. In the United States, food-borne diseases are responsible for 76 million cases of illness, 32,500 cases of hospitalisation and 5000 cases of death yearly. The ongoing increase in worldwide trade in livestock, food, and food products in combination with increase in human mobility (business- and leisure travel, emigration etc.) will increase the risk of emergence and spreading of such pathogens. There is therefore an urgent need for development of rapid, efficient and reliable methods for detection and identification of such pathogens.

Microchipfabrication has had a major impact on electronics and is expected to have an equally pronounced effect on life sciences. By combining micro-fluidics with micromechanics, micro-optics, and microelectronics, systems can be realized to perform complete chemical or biochemical analyses. These socalled ’Lab-on-a-Chip’ will completely change the face of laboratories in the future where smaller, fully automated devices will be able to perform assays faster, more accurately, and at a lower cost than equipment of today. A general introduction of food safety and applied micro-nanotechnology in life sciences will be given. In addition, examples of DNA micro arrays, micro fabricated integrated PCR chips and total integrated lab-on-achip systems from different National and EU research projects being carried out at the Laboratory of Applied Micro- Nanotechnology (LAMINATE) group at the National Veterinary Institute (DTU-Vet) Technical University of Denmark and the BioLabchip group at the Department of Micro and Nanotechnology (DTU-Nanotech), Technical University of Denmark (DTU), Ikerlan-IK4 (Spain) and other 16 partners from different European countries will be presented.

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In this study, we describe a simple and efficient method for on-chip storage of reagents for point-of-care (POC) diagnostics. The method is based on gelification of all reagents required for on-chip PCR-based diagnostics as a ready-to-use product. The result reported here is a key step towards the development of a ready and easy to use fully integrated Lab-on-a-chip (LOC) system for fast, cost-effective and efficient POC diagnostics analysis.