The field of biomaterials has become a vital area, as these materials can enhance the quality and longevity of human life and the science and technology associated with this field has now led to ...multi-million dollar business. The paper focuses its attention mainly on titanium-based alloys, even though there exists biomaterials made up of ceramics, polymers and composite materials. The paper discusses the biomechanical compatibility of many metallic materials and it brings out the overall superiority of Ti based alloys, even though it is costlier. As it is well known that a good biomaterial should possess the fundamental properties such as better mechanical and biological compatibility and enhanced wear and corrosion resistance in biological environment, the paper discusses the influence of alloy chemistry, thermomechanical processing and surface condition on these properties. In addition, this paper also discusses in detail the various surface modification techniques to achieve superior biocompatibility, higher wear and corrosion resistance. Overall, an attempt has been made to bring out the current scenario of Ti based materials for biomedical applications.
Objectives To determine whether a lifestyle integrated approach to balance and strength training is effective in reducing the rate of falls in older, high risk people living at home. Design Three ...arm, randomised parallel trial; assessments at baseline and after six and 12 months. Randomisation done by computer generated random blocks, stratified by sex and fall history and concealed by an independent secure website.Setting Residents in metropolitan Sydney, Australia.Participants Participants aged 70 years or older who had two or more falls or one injurious fall in past 12 months, recruited from Veteran’s Affairs databases and general practice databases. Exclusion criteria were moderate to severe cognitive problems, inability to ambulate independently, neurological conditions that severely influenced gait and mobility, resident in a nursing home or hostel, or any unstable or terminal illness that would affect ability to do exercises.Interventions Three home based interventions: Lifestyle integrated Functional Exercise (LiFE) approach (n=107; taught principles of balance and strength training and integrated selected activities into everyday routines), structured programme (n=105; exercises for balance and lower limb strength, done three times a week), sham control programme (n=105; gentle exercise). LiFE and structured groups received five sessions with two booster visits and two phone calls; controls received three home visits and six phone calls. Assessments made at baseline and after six and 12 months. Main outcome measures Primary measure: rate of falls over 12 months, collected by self report. Secondary measures: static and dynamic balance; ankle, knee and hip strength; balance self efficacy; daily living activities; participation; habitual physical activity; quality of life; energy expenditure; body mass index; and fat free mass.Results After 12 months’ follow-up, we recorded 172, 193, and 224 falls in the LiFE, structured exercise, and control groups, respectively. The overall incidence of falls in the LiFE programme was 1.66 per person years, compared with 1.90 in the structured programme and 2.28 in the control group. We saw a significant reduction of 31% in the rate of falls for the LiFE programme compared with controls (incidence rate ratio 0.69 (95% confidence interval 0.48 to 0.99)); the corresponding difference between the structured group and controls was non-significant (0.81 (0.56 to 1.17)). Static balance on an eight level hierarchy scale, ankle strength, function, and participation were significantly better in the LiFE group than in controls. LiFE and structured groups had a significant and moderate improvement in dynamic balance, compared with controls. Conclusions The LiFE programme provides an alternative to traditional exercise to consider for fall prevention. Functional based exercise should be a focus for interventions to protect older, high risk people from falling and to improve and maintain functional capacity.Trial registration Australia and New Zealand Clinical Trials Registry 12606000025538.
Network meta-analysis (NMA), combining direct and indirect comparisons, is increasingly being used to examine the comparative effectiveness of medical interventions. Minimal guidance exists on how to ...rate the quality of evidence supporting treatment effect estimates obtained from NMA. We present a four-step approach to rate the quality of evidence in each of the direct, indirect, and NMA estimates based on methods developed by the GRADE working group. Using an example of a published NMA, we show that the quality of evidence supporting NMA estimates varies from high to very low across comparisons, and that quality ratings given to a whole network are uninformative and likely to mislead.
In this critical review, we summarized the evidence on associations between individual/household income and oral health, between income inequality and oral health, and income-related inequalities in ...oral health. Meta-analyses of mainly cross-sectional studies confirm that low individual/household income is associated with oral cancer (odds ratio, 2.41; 95% confidence interval CI, 1.59–3.65), dental caries prevalence (prevalence ratio, 1.29; 95% CI, 1.18–1.41), any caries experience (odds ratio, 1.40; 95% CI, 1.19–1.65), tooth loss (odds ratio, 1.66; 95% CI, 1.48–1.86), and traumatic dental injuries (odds ratio, 0.76; 95% CI, 0.65–0.89). Reviews also confirm qualitatively that low income is associated with periodontal disease and poor oral health–related quality of life. Limited evidence from the United States shows that psychosocial and behavioral explanations only partially explain associations between low individual/household income and oral health. Few country-level studies and a handful of subnational studies from the United States, Japan, and Brazil show associations between area-level income inequality and poor oral health. However, this evidence is conflicting given that the association between area-level income inequality and oral health outcomes varies considerably by contexts and by oral health outcomes. Evidence also shows cross-national variations in income-related inequalities in oral health outcomes of self-rated oral health, dental care, oral health–related quality of life, outcomes of dental caries, and outcomes of tooth loss. There is a lack of discussion in oral health literature about limitations of using income as a measure of social position. Future studies on the relationship between income and oral health can benefit substantially from recent theoretical and methodological advancements in social epidemiology that include application of an intersectionality framework, improvements in reporting of inequality, and causal modeling approaches. Theoretically well-informed studies that apply robust epidemiological methods are required to address knowledge gaps for designing relevant policy interventions to reduce income-related inequalities in oral health.
Impaired sleep quality and quantity are associated with future morbidity and mortality. Exercise may be an effective non-pharmacological intervention to improve sleep, however, little is known on the ...effect of resistance exercise. Thus, we performed a systematic review of the literature to determine the acute and chronic effects of resistance exercise on sleep quantity and quality. Thirteen studies were included. Chronic resistance exercise improves all aspects of sleep, with the greatest benefit for sleep quality. These benefits of isolated resistance exercise are attenuated when resistance exercise is combined with aerobic exercise and compared to aerobic exercise alone. However, the acute effects of resistance exercise on sleep remain poorly studied and inconsistent. In addition to the sleep benefits, resistance exercise training improves anxiety and depression. These results suggest that resistance exercise may be an effective intervention to improve sleep quality. Further research is needed to better understand the effects of acute resistance exercise on sleep, the physiological mechanisms underlying changes in sleep, the changes in sleep architecture with chronic resistance exercise, as well its efficacy in clinical cohorts who commonly experience sleep disturbance. Future studies should also examine time-of-day and dose–response effects to determine the optimal exercise prescription for sleep benefits.
Abstract Objectives Osteoporotic fractures are associated with substantial morbidity and mortality. Although exercise has long been recommended for the prevention and management of osteoporosis, ...existing guidelines are often non-specific and do not account for individual differences in bone health, fracture risk and functional capacity. The aim of the current position statement is to provide health practitioners with specific, evidence-based guidelines for safe and effective exercise prescription for the prevention or management of osteoporosis, accommodating a range of potential comorbidities. Design Position statement. Methods Interpretation and application of research reports describing the effects of exercise interventions for the prevention and management of low bone mass, osteoporosis and osteoporotic fracture. Results Evidence from animal and human trials indicates that bone responds positively to impact activities and high intensity progressive resistance training. Furthermore, the optimisation of muscle strength, balance and mobility minimises the risk of falls (and thereby fracture), which is particularly relevant for individuals with limited functional capacity and/or a very high risk of osteoporotic fracture. It is important that all exercise programs be accompanied by sufficient calcium and vitamin D, and address issues of comorbidity and safety. For example, loaded spine flexion is not recommended, and impact activities may require modification in the presence of osteoarthritis or frailty. Conclusions Specific guidelines for safe and effective exercise for bone health are presented. Individual exercise prescription must take into account existing bone health status, co-morbidities, and functional or clinical risk factors for falls and fracture.
A systematic study on the chemical characteristics of ambient PM2.5, collected during October-2011 to March-2012 from a source region (Patiala: 30.2°N, 76.3°E; 250 m amsl) of biomass burning ...emissions in the Indo-Gangetic Plain (IGP), exhibit pronounced diurnal variability in mass concentrations of PM2.5, NO3−, NH4+, K+, OC, and EC with ∼30–300% higher concentrations in the nighttime samples. The average WSOC/OC and SO42−/PM2.5 ratios for the daytime (∼0.65, and 0.18, respectively) and nighttime (0.45, and 0.12, respectively) samples provide evidence for secondary organic and SO42− aerosol formation during the daytime. Formation of secondary NO3− is also evident from higher NH4NO3 concentrations associated with lower temperature and higher relative humidity conditions. The scattering species (SO42− + NO3− + OC) contribute ∼50% to PM2.5 mass during October–March whereas absorbing species (EC) contribute only ∼4% in October–February and subsequently increases to ∼10% in March, indicating significance of these species in regional radiative forcing.
•Striking diurnal variability has been observed in PM2.5 mass and chemical species.•Secondary organic and inorganic aerosol formation were evident in all periods.•Meteorology played important role in secondary aerosol formation over IGP.•Scattering species (SO42−, NO3−, OC) in PM2.5 were always dominant (∼50%).•Absorbing species (EC fraction) in PM2.5 increases (4–10%) from October to March.
Striking diurnal variability in PM2.5 mass and chemical species with the evidence of secondary organic and inorganic aerosol formation over the Indo-Gangetic Plain has been discussed.
Mild cognitive impairment (MCI) increases dementia risk with no pharmacologic treatment available.
The Study of Mental and Resistance Training was a randomized, double-blind, double-sham controlled ...trial of adults with MCI. Participants were randomized to 2 supervised interventions: active or sham physical training (high intensity progressive resistance training vs seated calisthenics) plus active or sham cognitive training (computerized, multidomain cognitive training vs watching videos/quizzes), 2-3 days/week for 6 months with 18-month follow-up. Primary outcomes were global cognitive function (Alzheimer's Disease Assessment Scale-cognitive subscale; ADAS-Cog) and functional independence (Bayer Activities of Daily Living). Secondary outcomes included executive function, memory, and speed/attention tests, and cognitive domain scores.
One hundred adults with MCI 70.1 (6.7) years; 68% women were enrolled and analyzed. Resistance training significantly improved the primary outcome ADAS-Cog; relative effect size (95% confidence interval) -0.33 (-0.73, 0.06); P < .05 at 6 months and executive function (Wechsler Adult Intelligence Scale Matrices; P = .016) across 18 months. Normal ADAS-Cog scores occurred in 48% (24/49) after resistance training vs 27% (14/51) without resistance training P < .03; odds ratio (95% confidence interval) 3.50 (1.18, 10.48). Cognitive training only attenuated decline in Memory Domain at 6 months (P < .02). Resistance training 18-month benefit was 74% higher (P = .02) for Executive Domain compared with combined training z-score change = 0.42 (0.22, 0.63) resistance training vs 0.11 (-0.60, 0.28) combined and 48% higher (P < .04) for Global Domain z-score change = .0.45 (0.29, 0.61) resistance training vs 0.23 (0.10, 0.36) combined.
Resistance training significantly improved global cognitive function, with maintenance of executive and global benefits over 18 months.
Investigations of exercise and cognition have primarily focused on healthy or demented older adults, and results have been equivocal in individuals with mild cognitive impairment (MCI). Our aim was ...to evaluate efficacy of exercise on cognition in older adults with MCI.
We conducted a meta-analysis of random controlled trials (RCTs) of exercise effects on cognitive outcomes in adults with MCI. Searches were conducted in Medline, EMBASE, CINAHL, PEDro, SPORTSDICUS, PsychInfo, and PubMed.
Adults aged over 65 years with MCI or Mini-Mental State Exam mean score 24-28 inclusive.
Study quality was assessed using the PEDro scale; data on participant and intervention characteristics and outcomes were extracted, followed by meta-analysis.
Fourteen RCTs (1,695 participants; age 65-95 years) met inclusion criteria. Quality was modest and under-powering for small effects prevalent. Overall, 42% of effect sizes (ESs) were potentially clinically relevant (ES >0.20) with only 8% of cognitive outcomes statistically significant. Meta-analysis revealed negligible but significant effects of exercise on verbal fluency (ES: 0.17 0.04, 0.30). No significant benefit was found for additional executive measures, memory, or information processing. Overall results were inconsistent with benefits varying across exercise types and cognitive domains.
There is very limited evidence that exercise improves cognitive function in individuals with MCI, although published research is of moderate quality and inconclusive due to low statistical power. Questions remain regarding the magnitude, generalization, persistence, and mechanisms of benefits. Large-scale, high-quality RCTs are required to determine if exercise improves cognition or reduces dementia incidence in those with MCI.
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