Acoustic emission signal processing framework to identify fracture in aluminum alloys

Acoustic emission (AE) is a common nondestructive evaluation tool that has been used to monitor fracture in materials and structures. The direct connection between AE events and their source, however, is difficult because of material, geometry and sensor contributions to the recorded signals. Moreover, the recorded AE activity is affected by several noise sources which further complicate the identification process. This article uses a combination of in situ experiments inside the scanning electron microscope to observe fracture in an aluminum alloy at the time and scale it occurs and a novel AE signal processing framework to identify characteristics that correlate with fracture events. Specifically, a signal processing method is designed to cluster AE activity based on the selection of a subset of features objectively identified by examining their correlation and variance. The identified clusters are then compared to both mechanical and in situ observed microstructural damage. Results from a set of nanoindentation tests as well as a carefully designed computational model are also presented to validate the conclusions drawn from signal processing

THE IMPACT OF DIETARY PROTEIN OR AMINO ACID SUPPLEMENTATION ON MUSCLE MASS AND STRENGTH IN ELDERLY PEOPLE: INDIVIDUAL PARTICIPANT DATA AND META-ANALYSIS OF RCT’S

Objectives Increasing protein or amino acid intake has been promoted as a promising strategy to increase muscle mass and strength in elderly people, however, long-term intervention studies show inconsistent findings. Therefore, we aim to determine the impact of protein or amino acid supplementation compared to placebo on muscle mass and strength in older adults by combining the results from published trials in a metaanalysis and pooled individual participant data analysis. Design We searched Medline and Cochrane databases and performed a meta-analysis on eight available trials on the effect of protein or amino acid supplementation on muscle mass and strength in older adults. Furthermore, we pooled individual data of six of these randomized double-blind placebo-controlled trials. The main outcomes were change in lean body mass and change in muscle strength for both the meta-analysis and the pooled analysis. Results The meta-analysis of eight studies (n=557) showed no significant positive effects of protein or amino acid supplementation on lean body mass (mean difference: 0.014 kg: 95% CI -0.152; 0.18), leg press strength (mean difference: 2.26 kg: 95% CI -0.56; 5.08), leg extension strength (mean difference: 0.75 kg: 95% CI: -1.96, 3.47) or handgrip strength (mean difference: -0.002 kg: 95% CI -0.182; 0.179). Likewise, the pooled analysis showed no significant difference between protein and placebo treatment on lean body mass (n=412: p=0.78), leg press strength (n=121: p=0.50), leg extension strength (n=121: p=0.16) and handgrip strength (n=318: p=0.37). Conclusions There is currently no evidence to suggest that protein or amino acid supplementation without concomitant nutritional or exercise interventions increases muscle mass or strength in predominantly healthy elderly people

Assessing validity of a short food frequency questionnaire on present dietary intake of elderly Icelanders

<p>Abstract</p> <p>Background</p> <p>Few studies exist on the validity of food frequency questionnaires (FFQs) administered to elderly people. The aim of this study was to assess the validity of a short FFQ on present dietary intake, developed specially for the AGES-Reykjavik Study, which includes 5,764 elderly individuals. Assessing the validity of FFQs is essential before they are used in studies on diet-related disease risk and health outcomes.</p> <p>Method</p> <p>128 healthy elderly participants (74 y ± 5.7; 58.6% female) answered the AGES-FFQ, and subsequently filled out a 3-day weighed food record. Validity of the AGES-FFQ was assessed by comparing its answers to the dietary data obtained from the weighed food records, using Spearman's rank correlation, Chi-Square/Kendall's tau, and a Jonckheere-Terpstra test for trend.</p> <p>Result</p> <p>For men a correlation ≥ 0.4 was found for potatoes, fresh fruits, oatmeal/muesli, cakes/cookies, candy, dairy products, milk, pure fruit juice, cod liver oil, coffee, tea and sugar in coffee/tea (r = 0.40-0.71). A lower, but acceptable, correlation was also found for raw vegetables (r = 0.33). The highest correlation for women was found for consumption of rye bread, oatmeal/muesli, raw vegetables, candy, dairy products, milk, pure fruit juice, cod liver oil, coffee and tea (r = 0.40-0.61). An acceptable correlation was also found for fish topping/salad, fresh fruit, blood/liver sausage, whole-wheat bread, and sugar in coffee/tea (r = 0.28-0.37). Questions on meat/fish meals, cooked vegetables and soft drinks did not show a significant correlation to the reference method. Pearson Chi-Square and Kendall's tau showed similar results, as did the Jonckheere-Terpstra trend test.</p> <p>Conclusion</p> <p>A majority of the questions in the AGES-FFQ had an acceptable correlation and may be used to rank individuals according to their level of intake of several important foods/food groups. The AGES-FFQ on present diet may therefore be used to study the relationship between consumption of several specific foods/food groups and various health-related endpoints gathered in the AGES-Reykjavik Study.</p

Genome-Wide Association Study of Plasma Polyunsaturated Fatty Acids in the InCHIANTI Study

Polyunsaturated fatty acids (PUFA) have a role in many physiological processes, including energy production, modulation of inflammation, and maintenance of cell membrane integrity. High plasma PUFA concentrations have been shown to have beneficial effects on cardiovascular disease and mortality. To identify genetic contributors of plasma PUFA concentrations, we conducted a genome-wide association study of plasma levels of six omega-3 and omega-6 fatty acids in 1,075 participants in the InCHIANTI study on aging. The strongest evidence for association was observed in a region of chromosome 11 that encodes three fatty acid desaturases (FADS1, FADS2, FADS3). The SNP with the most significant association was rs174537 near FADS1 in the analysis of arachidonic acid (AA; p = 5.95×10−46). Minor allele homozygotes had lower AA compared to the major allele homozygotes and rs174537 accounted for 18.6% of the additive variance in AA concentrations. This SNP was also associated with levels of eicosadienoic acid (EDA; p = 6.78×10−9) and eicosapentanoic acid (EPA; p = 1.07×10−14). Participants carrying the allele associated with higher AA, EDA, and EPA also had higher low-density lipoprotein (LDL-C) and total cholesterol levels. Outside the FADS gene cluster, the strongest region of association mapped to chromosome 6 in the region encoding an elongase of very long fatty acids 2 (ELOVL2). In this region, association was observed with EPA (rs953413; p = 1.1×10−6). The effects of rs174537 were confirmed in an independent sample of 1,076 subjects participating in the GOLDN study. The ELOVL2 SNP was associated with docosapentanoic and DHA but not with EPA in GOLDN. These findings show that polymorphisms of genes encoding enzymes in the metabolism of PUFA contribute to plasma concentrations of fatty acids

Frailty Intervention Trial (FIT)

<p>Abstract</p> <p>Background</p> <p>Frailty is a term commonly used to describe the condition of an older person who has chronic health problems, has lost functional abilities and is likely to deteriorate further. However, despite its common use, only a small number of studies have attempted to define the syndrome of frailty and measure its prevalence. The criteria Fried and colleagues used to define the frailty syndrome will be used in this study (i.e. weight loss, fatigue, decreased grip strength, slow gait speed, and low physical activity). Previous studies have shown that clinical outcomes for frail older people can be improved using multi-factorial interventions such as comprehensive geriatric assessment, and single interventions such as exercise programs or nutritional supplementation, but no interventions have been developed to specifically reverse the syndrome of frailty.</p> <p>We have developed a multidisciplinary intervention that specifically targets frailty as defined by Fried et al. We aim to establish the effects of this intervention on frailty, mobility, hospitalisation and institutionalisation in frail older people.</p> <p>Methods and Design</p> <p>A single centre randomised controlled trial comparing a multidisciplinary intervention with usual care. The intervention will target identified characteristics of frailty, functional limitations, nutritional status, falls risk, psychological issues and management of chronic health conditions. Two hundred and thirty people aged 70 and over who meet the Fried definition of frailty will be recruited from clients of the aged care service of a metropolitan hospital. Participants will be followed for a 12-month period.</p> <p>Discussion</p> <p>This research is an important step in the examination of specifically targeted frailty interventions. This project will assess whether an intervention specifically targeting frailty can be implemented, and whether it is effective when compared to usual care. If successful, the study will establish a new approach to the treatment of older people at risk of further functional decline and institutionalisation. The strategies to be examined are readily transferable to routine clinical practice and are applicable broadly in the setting of aged care health services.</p> <p>Trial Registration</p> <p>Australian New Zealand Clinical Trails Registry: ACTRN12608000250336.</p

Obesity prevalence from a European perspective: a systematic review

<p>Abstract</p> <p>Background</p> <p>Obesity has been recognised as an important contributing factor in the development of various diseases, but comparative data on this condition are limited. We therefore aimed to identify and discuss current epidemiological data on the prevalence of obesity in European countries.</p> <p>Methods</p> <p>We identified relevant published studies by means of a MEDLINE search (1990–2008) supplemented by information obtained from regulatory agencies. We only included surveys that used direct measures of weight and height and were representative of each country's overall population.</p> <p>Results</p> <p>In Europe, the prevalence of obesity (body mass index ≥ 30 kg/m²) in men ranged from 4.0% to 28.3% and in women from 6.2% to 36.5%. We observed considerable geographic variation, with prevalence rates in Central, Eastern, and Southern Europe being higher than those in Western and Northern Europe.</p> <p>Conclusion</p> <p>In Europe, obesity has reached epidemic proportions. The data presented in our review emphasise the need for effective therapeutic and preventive strategies.</p

Influence of disinfectant solutions on test materials used for the determination of masticatory performance

Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG)Empresa de Pesquisa Agropecu?ria de Minas Gerais (EPAMIG)Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq)Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)Masticatory function can be evaluated objectively as the capacity of an individual to fragment solid food after a fixed number of chewing cycles, the so-called masticatory performance (MP). The objective of this study was to evaluate the reliability of four different test materials (Optosil, Optocal, Zetapuls, and Perfil) and five disinfection protocols by aspersion and immersion (no disinfection, 2% glutaraldehyde, 2% chlorhexidine, 5.25% sodium hypochlorite, and 70% alcohol) on the MP, determined at three moments (24 hours, 15 and 60 days) after storing the fragmented blocks. MP was evaluated by calculating X50 through the sieving technique and the Rosim-Ramler equation. The weight and microbiologic count (colony forming units, CFUs) of chewed blocks were measured to identify any variations that would make MP determination unfeasible. Differences in MP were observed among the materials (p 0.05). The time and disinfection type had no influence on MP (p > 0.05). The number of CFUs differed between the nondisinfected group and all other disinfection groups at all time points (p < 0.01). No other significant difference in CFU count between disinfection groups was observed. In conclusion, disinfection did not alter the reliability of the test materials for the MP calculation for up to 60 days