Musculoskeletal, visual and psychosocial stress in VDU operators before and after multidisciplinary ergonomic interventions. A 6 years prospective study—Part II

A prospective epidemiological field study covering a 2 years period has earlier been published (Appl. Ergon. (1998) 29(5) 335). The study has a parallel group design with two intervention groups (T and S) and one control group (C) of Visual Display Unit (VDU) operators. The present paper covers the period from 2 to 6 years of the study. After 3.5 years, the C group got the same intervention in terms of new lighting system, new workplaces and at last an optometric examination and corrections if needed. The C group reported a significant reduction in visual discomfort after interventions while the two groups (T and S) continued to report significant reduction of visual discomfort after 6 years. By supporting the forearm on the table top, the C group reported significant reduction of shoulder and neck pain while the T group reported significant reduction in shoulder and back pain after 6 years. Organizational and psychosocial factors at work and outside work did not show any significant changes during the study period.     

Laboratory Investigation of Mean Drag in a Random Array of Rigid, Emergent Cylinders

This paper investigates the drag exerted by randomly distributed, rigid, emergent circular cylinders of uniform diameter d. Laboratory measurements are presented for solid volume fraction ? = 0.091, 0.15, 0.20, 0.27, and 0.35 and cylinder Reynolds number Rep ≡ Upd/ν = 25 to 685, where Up=temporally and cross-sectionally averaged pore velocity and ν=kinematic viscosity. These ranges coincide with conditions in aquatic plant canopies. The temporally and cross-sectionally averaged drag coefficient, CD, decreased with increasing Rep and increased with increasing ? under the flow conditions investigated. The dimensionless ratio of the mean drag per unit cylinder length 〈〉H to the product of the viscosity, μ, and Up exhibits a linear Rep dependence of the form 〈〉H/(μUp) = α0+α1Rep, consistent with Ergun’s formulation for packed columns. In the range of experimental conditions, α1 increases monotonically with ?. In contrast, α0 is constant within uncertainty for 0.15 ? ? ? 0.35, which suggests that viscous drag per unit cylinder length is independent of ? in this range.     

High surface area nanostructured tubes prepared by dissolution of ALD-coated electrospun fibers

Novel nanostructured and high surface area tubular materials were produced combining electrospinning and atomic layer deposition processes with the removal of polymeric template via dissolution. The dissolution process changed the structure of the tube walls, and the smooth atomic layer deposition coating was transformed into a highly complex, coral-like structure. This material, which we have called “nanocoral,” has a relatively high surface area, 323 m² g⁻¹, due to the interconnected cavities formed after the removal of the template. This kind of material has important potential applications, for example, in the fields of catalysts and filtration.     

Primary food sources of nutrients in the diet of Canadian adults.

PURPOSE: Food sources of nutrients in the Canadian diet were explored. Knowledge of these sources is important to public health professionals and to those in clinical practice. METHODS: Using data from the Food Habits of Canadians study, we investigated nutrient sources from detailed food groupings in a sample of 1,543 adults (971 women, 572 men) from across Canada. Subjects were interviewed by trained dietitians. At the time of the interview, a sociodemographic questionnaire and a 24-hour dietary recall were completed. RESULTS: The response rate was 30%. Subjects aged 18 to 34 reported eating more prepared and convenience foods than did those aged 35 to 65. Energy was contributed mainly by breads, pasta, rice, grains, and fluid milk. Protein intake was primarily derived from meat and dairy products; legumes, nuts, seeds, and eggs were not high contributors. For men aged 35 to 65 and women aged 18 to 65, butter, margarine, and oil were the primary fat sources; they were the second most common source for men aged 18 to 34. Fibre was provided by foods that are not usually considered good sources, but because of the large total consumption of these foods, they are important in Canadians' diet. The main source of calcium was dairy products, and iron came mainly from non-heme sources. CONCLUSIONS: We must understand the contributions of foods to nutrients, and distinguish "important" sources of nutrients (those consumed by many in substantial amounts) from "good" sources (foods rich in particular nutrients, whether eaten or not).     

Whey beverages decrease blood pressure in prehypertensive and hypertensive young men and women

Whey protein beverages reduced blood pressure in young men and women in a six week controlled intervention. There were no differences in systolic blood pressure (SBP), diastolic blood pressure (DBP), or mean arterial pressure (MAP) observed between groups consuming 28 g per day of either hydrolyzed or non-hydrolyzed whey protein in a beverage. However, in young adults with elevated DBP and SBP, whey beverage consumption significantly decreased SBP, DBP, and MAP by 8.0, 8.6, and 6.4 mm Hg, respectively (P ≤ 0.001 for all comparisons). In subjects with elevated SBP only, SBP significantly decreased by 3.8 mm Hg (P ≤ 0.04) after the whey beverage intervention. Subjects with normal blood pressure had no change in SBP, DBP, and MAP. Whey beverages also significantly decreased total and low-density lipoprotein cholesterol concentrations (P ≤ 0.001 and 0.05, respectively). Whey protein beverages may be useful for the dietary treatment of prehypertension and/or stage 1 hypertension.     

Determining the Applicability of Threshold of Toxicological Concern Approaches to Substances Found in Foods

Threshold of Toxicological Concern (TTC) decision-support methods present a pragmatic approach to using data from well-characterized chemicals and protective estimates of exposure in a stepwise fashion to inform decisions regarding low-level exposures to chemicals for which few data exist. It is based on structural and functional categorizations of chemicals derived from decades of animal testing with a wide variety of chemicals. Expertise is required to use the TTC methods, and there are situations in which its use is clearly inappropriate or not currently supported. To facilitate proper use of the TTC, this paper describes issues to be considered by risk managers when faced with the situation of an unexpected substance in food. Case studies are provided to illustrate the implementation of these considerations, demonstrating the steps taken in deciding whether it would be appropriate to apply the TTC approach in each case. By appropriately applying the methods, employing the appropriate scientific expertise, and combining use with the conservative assumptions embedded within the derivation of the thresholds, the TTC can realize its potential to protect public health and to contribute to efficient use of resources in food safety risk management.     

High‐Pressure Synthesis of Tantalum Nitride Having Orthorhombic U2S3 Structure

Among binary compounds, there is a high potential for discovery of novel members (polymorphic phases or compounds) of the nitrides of transition metals group due to a pronounced dependence of the oxidation state of the metals (M) on pressure. The power of high pressure–high temperature (HP‐HT) route for synthesis of binary nitrides has already been demonstrated by the discovery of cubic nitrides of the group 4 and 14 elements, of crystalline polymorphs of P₃N₅, and by reports on formation of four noble metal nitrides. It is anticipated that such HP products exhibit, in addition to enhanced elastic and mechanical behavior, other functional properties making them interesting for industrial applications. Here, HP–HT synthesis research is extended to nitrides of group 5 elements, resulting in the discovery of a novel hard tantalum nitride, exhibiting U₂S₃ structure: η‐Ta₂N₃ (Pbnm, a = 8.1911(17) Å, b = 8.1830(17) Å, c = 2.9823(3) Å). The stoichiometry is supported by two independent means, verifying that η‐Ta₂N₃ is the first thermodynamically stable transition metal nitride with a N:M ratio exceeding 4:3. Due to its high hardness and peculiar texture (needle‐like and granular crystallites), η‐Ta₂N₃ may find practical applications as a hard fracture resistant material.