The addition of a surfactant at regular time intervals in the mechanical alloying process

The impact of regular additions of a surfactant (ethylene bis-stearamide; EBS) at different time intervals was investigated on the powder characteristics of a biomedical Ti-10Nb-3Mo alloy (wt.%). Ball milling was performed for 10 h on the elemental powders in four series of experiments at two rotation speeds (200 and 300 rpm). The addition of 2 wt.% total EBS at different time intervals during ball milling resulted in noticeable changes in particle size and morphology of the powders. The surfactant addition at shorter time intervals led to the formation of finer particles, a more homogenous powder distribution, a higher powder yield, and a lower contamination content in the final materials. Thermal analysis of the powders after ball milling suggested that differing decomposition rates of the surfactant were responsible for the measured powder particle changes and contamination contents. The results also indicated that the addition of surfactant during ball milling at 200 rpm caused a delay in the alloy formation, whereas ball milling at 300 rpm favored the formation of the titanium alloy.Crown Copyright © 2014 Published by Elsevier B.V. All rights reserved.

Neighborhood environmental attributes and adults' maintenance of regular walking

Environmental initiatives to support walking are keys to non-communicable disease prevention, but the relevant evidence comes mainly from cross-sectional studies. We examined neighborhood environmental attributes associated cross-sectionally with walking and those associated prospectively with walking maintenance.

Are the profiles of past-year internet gamblers generalizable to regular internet gamblers?

 Research generally classifies internet gamblers as those who have gambled online at least once in the previous year. This classification system has been criticised on the grounds that it fails to consider the frequency of internet gambling. This study aimed to contrast the demographic, gambling, and psychosocial profiles of regular internet gamblers (at least monthly in the previous year) with those of past-year internet gamblers. Computer-assisted telephone interviews were conducted with 4303 adult respondents from Tasmania, Australia. The findings revealed that 3.3% were past-year internet gamblers and 2.1% were regular internet gamblers. Both past-year and regular internet gambling were significantly associated with several variables (younger age, dependent children, paid employment, higher annual income, higher gambling frequency and expenditure, younger age of first gambling, challenge and positive feelings gambling motives, and positive reinforcement gambling triggers). However, several variables were significantly associated only with past-year internet gambling (male gender, living with partner, number of gambling activities, regulate internal state gambling motives, hazardous alcohol use, cannabis use, and other illicit drug use) or regular internet gambling (higher education). Only gambling for positive feelings was a significant independent predictor of both past-year and regular internet gambling. These findings suggest that the classification of past-year internet gambling that is normally employed in research produces profiles that are not fully generalizable to regular internet gamblers.

Genotoxicity evaluation of chlorpyrifos: a gender related approach in regular toxicity testing

The oral intubation of chlorpyrifos, an extensively used organophosphate insecticide, was tested for its capability to induce in vivo genotoxic upshot in blood lymphocytes of 24 male and female Wistar rats using biomarker of genotoxicity. Rats were orally administered with daily doses 3 and 12 mg/kg body weight (BW) of chlorpyrifos (CPF). The blood lymphocytes were harvested after 7 and 14 days of treatment and subjected to bi-nucleus (BN), multi-nucleus (MN) and single cell gel electrophoresis (comet assay) to evaluate the extent of DNA damage. Other than BN and MN assay, damage to DNA was assessed through comet length, height, area, head diameter, head DNA percentage and tail DNA percentage along with tail movement. A significant boost was noticed in the frequency of BN cells formation after 12 mg/kg BW CPF treatment. However, the propensity to produce MN cells was significantly more (P ≤ 0.05) in males than that of females. Likewise, the frequency of comet formation, mean comet length, height and area were more (P ≤ 0.05) in males than females even with 12 mg/kgBW. Comet head DNA % and tail length remained non-significant. Olive movement also revealed a significant increase (P ≤ 0.05) in males than females. The study inferred that the CPF can induce DNA damage in both male and female subjects but more pronounced in the male individuals.

Review : regular brisk walking improves cardiovascular risk factors in healthy sedentary adults

QUESTION In healthy sedentary adults, does regular brisk walking improve cardiovascular risk factors?

METHODS Data sources: Medline and Web of Science (1971 to September 2004) and reference lists.Study selection and assessment:English-language, randomised controlled trials (RCTs) with duration ⩾4 weeks that assessed the effects of walking as the only intervention on changes in cardiovascular risk factors in sedentary, but otherwise healthy, adults. 24 RCTs (n = 1128, mean age 52 y, 83% women) met the selection criteria. The mean length of the walking programmes was 35 weeks (range 8–104 wk). On average, walking was done 4.4 days/week for 38 minutes per session. The mean intensity of the walking interventions was 70% of predicted maximum heart rate or 56% of VO2 max. Quality of individual studies was assessed based on allocation concealment. Outcomes: cardiovascular fitness (VO2 max), body weight, percent body fat, body mass index, and systolic and diastolic blood pressure (BP).

MAIN RESULTS Brisk walking increased cardiovascular fitness and reduced body weight, body mass index, body fat composition, and diastolic BP more than the control condition (table). No effect on systolic BP was observed (table).

CONCLUSION In healthy sedentary adults, regular brisk walking improves cardiovascular fitness, body composition, and diastolic blood pressure.