287 research outputs found
Investigating mechanical characteristics of styli for micro-CMMs
The mechanical characteristics of styli for micro coordinate measuring machines (micro-CMMs) is of importance because of the major effect the styli have on the performance and capability of micro-CMMs. Previous work has focussed on the design of the next generation of stylus systems for micro-CMMs, and several test styli have been manufactured. These test styli have sphere-tips and stylus shaft diameters of less than 70 gm and 40 pm respectively, and aspect ratios of greater than ten. The styli are manufactured using a novel hybrid manufacturing process. In this paper the results of tests designed to determine the mechanical properties of the test styli will be presented. The experimental setup and testing method has been enhanced from that of the previous work, especially with respect to the precision manipulation stages and control software. The main focus of the work presented here is to measure the stiffness of the styli shafts and the transverse force on the tip that causes initial plastic behaviour in the stylus. The results of the mechanical properties measurements are also compared to results from analytical models. The outcome of this work will lead to a better understanding of the development of tactile stylus systems for micro-CMMs, with the aim of developing micro-styli with sphere-tip diameters of the order of 10 pm or less
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Comparative Risk of Cardiovascular Outcomes Between Topical and Oral Nonselective NSAIDs in Taiwanese Patients With Rheumatoid Arthritis
Background: Topical NSAIDs have less systemic absorption than oral NSAIDs. We examined the risk of cardiovascular events associated with nonselective topical NSAIDs versus oral NSAIDs among patients with rheumatoid arthritis in Taiwan. Methods and Results: We conducted a retrospective cohort study that included patients with incident rheumatoid arthritis who were newly starting therapy with nonselective topical NSAIDs or oral NSAIDs. We used the Taiwan National Health Insurance Research Database (NHIRD). The first date patients received either type of NSAID was defined as the index date. NSAID exposures continued until there was a treatment gap of >30 days. The main outcome was composite cardiovascular events, including myocardial infarction, unstable angina, heart failure, stroke, or revascularization. Followâup was censored at treatment discontinuation, switch or addition of other NSAID category, cardiovascular outcome, death, or the end of the study. Propensity score weighted Cox regression models were used to compare the risk of cardiovascular events between topical NSAIDs and oral NSAIDs. There were 10 758 and 78 056 treatment episodes for topical and oral NSAIDs identified. After weighting by propensity score, the cohorts were well balanced over all covariates. The crude cardiovascular event rate was 1.87 per 100 personâyears for topical NSAIDs and 2.14 per 100 personâyears for oral NSAIDs. Results of propensity score weighted Cox regression found the topical NSAID group had 36% lower risk for cardiovascular events compared with the oral NSAID group (hazard ratio, 0.64; 95% confidence interval, 0.43â0.95). Conclusions: We found topical NSAID users experienced a reduced risk of cardiovascular events compared with oral NSAID users. If future studies with a larger sample size and longer followâup confirm these results, NSAID prescribing might change accordingly
Chemical analysis of acoustically levitated drops by Raman spectroscopy
An experimental apparatus combining Raman spectroscopy with acoustic levitation, Raman acoustic levitation spectroscopy (RALS), is investigated in the field of physical and chemical analytics. Whereas acoustic levitation enables the contactless handling of microsized samples, Raman spectroscopy offers the advantage of a noninvasive method without complex sample preparation. After carrying out some systematic tests to probe the sensitivity of the technique to drop size, shape, and position, RALS has been successfully applied in monitoring sample dilution and preconcentration, evaporation, crystallization, an acidâbase reaction, and analytes in a surface-enhanced Raman spectroscopy colloidal suspension
Building Slavery-free Communities: A Resilience Framework
There is growing interest in the use of community-based approaches to address the causes of modern slavery and the related goal of building anti-slavery 'resilience'. However, the concept of resilience is often poorly understood and applied without attention to the specific challenges of anti-slavery policy and practice. This paper provides a conceptual framework for understanding the process and outcomes of building resilience against contemporary forms of slavery within place-based communities. Inspired by established ecological models of resilience, we propose an adaptive 'resilience cycle' that activists and policymakers can draw upon to inform the process of designing and delivering policy interventions. This process is combined with a review of evidence about the multi-level social determinants of modern slavery to suggest a framework of topic areas for local review and measurement, as a means to assess existing gaps and assets, enable comparative learning and measure progress towards goals. We also outline a future research agenda exploring locally-grounded perspectives on modern slavery risk and resilience, to improve understanding of the factors underpinning resilience across different social and economic contexts. This article will assist policy-makers by clarifying the concept of anti-slavery resilience, which can in turn inform policy design and implementation, and help to make connections between disparate initiatives from multiple actors. By combining a process for building resilience with an overview of social determinants underpinning a slavery-free community, we offer a basis for gap-analysis and ongoing measurement. The research agenda that we outline to better understand factors underpinning resilience would make a valuable contribution to improving anti-slavery governance and assist in developing a better understanding of the linkages between achieving SDG 8.7 and wider sustainable development goals
Women and citizenship post-trafficking : the case of Nepal
The research for this paper was funded by the Economic and Social Research Council â ESRC Res-062-23-1490: âPost Trafficking in Nepal: Sexuality and Citizenship in Livelihood Strategiesâ. Diane Richardson would like to acknowledge the support provided by the award of a Leverhulme TrustMajor Research Fellowship, âTransforming Citizenship: Sexuality, Gender and Citizenship Strugglesâ [award MRF-2012-106].This article analyses the relationship between gender, sexuality and citizenship embedded in models of citizenship in the Global South, specifically in South Asia, and the meanings associated with having - or not having - citizenship. It does this through an examination of women's access to citizenship in Nepal in the context of the construction of the emergent nation state in the 'new' Nepal 'post-conflict'. Our analysis explores gendered and sexualized constructions of citizenship in this context through a specific focus on women who have experienced trafficking, and are beginning to organize around rights to sustainable livelihoods and actively lobby for changes in citizenship rules which discriminate against women. Building from this, in the final section we consider important implications of this analysis of post-trafficking experiences for debates about gender, sexuality and citizenship more broadly.Publisher PDFPeer reviewe
Temporal Regulation of Rapamycin on Memory CTL Programming by IL-12
Mammalian target of rapamycin (mTOR) is a master regulator of cell growth. Recent reports have defined its important role in memory cytotoxic T lymphocyte (CTL) differentiation in infections and memory programming. We report that rapamycin regulated memory CTL programming by IL-12 to a similar level in a wide range of concentrations, and the enhanced memory CTLs by rapamycin were functional and provided similar protection against Listeria Monocytogenes challenge compared to the control. In addition, rapamycin-experienced CTLs went through substantially enhanced proliferation after transfer into recipients. Furthermore, the regulatory function of rapamycin on CD62L expression in memory CTLs was mainly contributed by the presence of rapamycin in the first 24-hr of stimulation in vitro, whereas the effective window of rapamycin on the size of memory CTLs was determined between 24 to 72 hrs. In conclusion, rapamycin regulates IL-12-driven programming of CTLs to a similar level in a wide range of concentrations, and regulates the phenotype and the size of memory CTLs in different temporal windows
Plasma lysophosphatidylcholine levels are reduced in obesity and type 2 diabetes
BACKGROUND: Obesity and type 2 diabetes (T2DM) are associated with increased circulating free fatty acids and triacylglycerols. However, very little is known about specific molecular lipid species associated with these diseases. In order to gain further insight into this, we performed plasma lipidomic analysis in a rodent model of obesity and insulin resistance as well as in lean, obese and obese individuals with T2DM. METHODOLOGY/PRINCIPAL FINDINGS: Lipidomic analysis using liquid chromatography coupled to mass spectrometry revealed marked changes in the plasma of 12 week high fat fed mice. Although a number of triacylglycerol and diacylglycerol species were elevated along with of a number of sphingolipids, a particularly interesting finding was the high fat diet (HFD)-induced reduction in lysophosphatidylcholine (LPC) levels. As liver, skeletal muscle and adipose tissue play an important role in metabolism, we next determined whether the HFD altered LPCs in these tissues. In contrast to our findings in plasma, only very modest changes in tissue LPCs were noted. To determine when the change in plasma LPCs occurred in response to the HFD, mice were studied after 1, 3 and 6 weeks of HFD. The HFD caused rapid alterations in plasma LPCs with most changes occurring within the first week. Consistent with our rodent model, data from our small human cohort showed a reduction in a number of LPC species in obese and obese individuals with T2DM. Interestingly, no differences were found between the obese otherwise healthy individuals and the obese T2DM patients. CONCLUSION: Irrespective of species, our lipidomic profiling revealed a generalized decrease in circulating LPC species in states of obesity. Moreover, our data indicate that diet and adiposity, rather than insulin resistance or diabetes per se, play an important role in altering the plasma LPC profile
Influence of social support on cognitive function in the elderly
BACKGROUND: Social support is important in daily activities of the elderly. This study tests the hypothesis that there is an association between social support and cognitive function among the elderly in a community setting. METHODS: Face-to-face interviews were conducted in a cross-sectional stratified random sample of 4,993 elderly (â„65 years) city residents. Using multiple regression analysis, we investigated the influence of social support on cognitive function. RESULTS: 12% were over 80 years old. 53.28% were men. 67.14% were married. Higher Short Portable Mental Status Questionnaire (SPMSQ) scores (higher score means better cognitive function) were associated with strong social support, as measured by marital status and perceived positive support from friends. Lower cognitive function was associated with older and with female respondents. Only instrumental activities of daily living (IADL) were statistically and negatively related to SPMSQ. Lower functional status was associated with lower cognitive function. Elders with grade school educations had lower SPMSQ scores than did elders with high school educations. CONCLUSIONS: In Taiwan, higher cognitive function in community-living elderly was associated with increased social support. Life-style management should provide social activities for the elderly to promote a better quality of life
The role of TNF genetic variants and the interaction with cigarette smoking for gastric cancer risk: a nested case-control study
<p>Abstract</p> <p>Background</p> <p>The aim of this study was to investigate the role of <it>TNF </it>genetic variants and the combined effect between <it>TNF </it>gene and cigarette smoking in the development of gastric cancer in the Korean population.</p> <p>Methods</p> <p>We selected 84 incident gastric cancer cases and 336 matched controls nested within the Korean Multi-Center Cancer Cohort. Six SNPs on the <it>TNF </it>gene, <it>TNF</it>-α-238 G/A, -308 G/A, -857 C/T, -863 C/A, -1031 T/C, and <it>TNF</it>-ÎČ 252 A/G were genotyped. The ORs (95% CIs) were calculated using unconditional logistic regression model to detect each SNP and haplotype-pair effects for gastric cancer. The combined effects between the <it>TNF </it>gene and smoking on gastric cancer risk were also evaluated. Multi dimensionality reduction (MDR) analyses were performed to explore the potential <it>TNF </it>gene-gene interactions.</p> <p>Results</p> <p><it>TNF</it>-α-857 C/T containing the T allele was significantly associated with an increased risk of gastric cancer and a linear trend effect was observed in the additive model (OR = 1.6, 95% CI 1.0â2.5 for CT genotype; OR = 2.6, 95% CI 1.0â6.4 for TT genotype). All haplotype-pairs that contained TCT or CCC of <it>TNF</it>-α-1031 T/C, <it>TNF</it>-α-863 C/A, and <it>TNF</it>-α-857 C/T were associated with a significantly higher risk for gastric cancer only among smokers. In the MDR analysis, regardless of smoking status, <it>TNF</it>-α-857 C/T was included in the first list of SNPs with a significant main effect.</p> <p>Conclusion</p> <p><it>TNF</it>-α-857 C/T polymorphism may play an independent role in gastric carcinogenesis and the risk for gastric cancer by <it>TNF </it>genetic effect is pronounced by cigarette smoking.</p
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