IEA joint trials: New lessons from old plantations

Two international trials of potential biomass species families and clones planted in 1985 have been analyzed to determine changing patterns in growth, diseases, and insects. In the Swedish trial, with close spacing and short rotations, Salix viminalis clones gave the best average yield of 17.4 Mg/Ha/yr on the first coppice rotation. In the Minnesota, USA trial, with wider spacings and a longer rotation Populus alba hybrid clones gave the best average yields of 5.5 Mg/Ha/yr. The most important disease and insect problems encountered were Septoria musiva stem cankers on some Populus clones; frost die back in some Salix clones; and the leaf blotch miner, Fenusa dohrnii, on most Alnus families. Recommendations for future international cooperation in field trials are presented.     

Synthesis of accurate fractional Gaussian noise by filtering

This paper describes a method for generating long sample paths of accurate fractional Gaussian noise (fGn), the increment process of fractional Brownian motion (fBm). The method is based on a Wold decomposition in which fGn is expressed as the output of a finite impulse response filter with discrete white Gaussian noise as input. The form of the ideal filter is derived analytically in the continuous-time case. For the finite-length discrete-time case, an iterative projection algorithm incorporating a Newton-Raphson step is described for computing the coefficients of a length-N filter in a time approximately proportional to N. Fast convolution of discrete white Gaussian noise with the computed filter impulse response yields arbitrarily long sequences which exactly match the correlation structure of fGn over a finite range of lags. For values of the Hurst parameter H smaller than a critical value H_critap0.85, and large N, the finite-length autocorrelation sequence of fGn is positive definite and this range of lags can be as large as the filter autocorrelation length. When H>H _crit, the finite-length autocorrelation sequence of fGn is no longer positive definite and a modification is made to allow a Wold decomposition. The generated sequences then exactly match the autocorrelation structure of fGn over a more restricted range of lags which becomes smaller as H approaches unity     

Temperature reduction due to the application of phase change materials

Overheating is a major problem in many modern buildings due to the utilization of lightweight constructions with low heat storing capacity. A possible answer to this problem is the emplacement of phase change materials (PCM), thereby increasing the thermal mass of a building. These materials change their state of aggregation within a defined temperature range. Useful PCM for buildings show a phase transition from solid to liquid and vice versa. The thermal mass of the materials is increased by the latent heat. A modified gypsum plaster and a salt mixture were chosen as two materials for the study of their impact on room temperature reduction. For realistic investigations, test rooms were erected where measurements were carried out under different conditions such as temporary air change, alternate internal heat gains or clouding. The experimental data was finally reproduced by dint of a mathematical model.     

Injury risk associated with physical demands and school environment characteristics among a cohort of custodial workers

Few epidemiological studies have investigated the relationship between work exposures and injury risk among custodians. The relationship between injury risk and occupational physical demands (e.g. pushing/pulling, lifting) and school environment characteristics (e.g. school type, season) was investigated among a cohort of 581 school custodians over a 4-year period. In the final Poisson regression models, the risk of injury was associated with time spent in pushing/pulling tasks in a dose-response manner increasing to a five-fold risk among the highest quartile of exposure (risk ratio?=?5.15, 95% CI 1.00, 26.5). Injury risk was also associated with working during the school year compared to the summer, working in a school with grass vs. gravel grounds and working in a school with detached classrooms. Results help to target interventions such as alternative methods for floor cleaning to reduce the pushing/pulling demands of custodial work and to support decisions for alternatives to detached classrooms and grass surfaces. Statement of Relevance: This study examines ergonomic factors (physical demand exposures, school environment characteristics) associated with injury risk among custodial school workers. The findings help schools to target interventions to reduce the physical demands associated with injuries and to design school environments to reduce exposures.     

A Warm Meal and a Bed: Intersections of Housing and Food Security in Vancouver's Downtown Eastside

The purpose of this paper is to highlight the relationships between housing, food security, and health. We begin by reviewing the current literature on the intersections of housing and food security, emphasizing the current gaps in knowledge in the areas of building infrastructure, in-house food programs, and building context for social housing. Derived from the literature review, we present a model designed to highlight the relationships between food, housing, and health. Following this, we provide a case study of housing and food security for residents of the Downtown Eastside. By examining the experiences of residents struggling to find both food and shelter within a very low-income context, we underscore the ways in which food, health, and housing intersect. We conclude by outlining future research directions that will enhance understanding of these intersections.     

Assessing attitudes, beliefs and readiness for musculoskeletal injury prevention in the construction industry

The objectives are to determine attitudes and beliefs among construction workers and supervisors related to taking action to reduce musculoskeletal injuries (MSIs). “Action” stage of change was confirmed if workers in the last 6 months are continuing to take steps to reduce MSIs. Surveys (520 workers; 35% and 171 supervisors; 67%) revealed that more workers are concerned about MSIs (p < 0.05) and are taking action to reduce MSIs (p < 0.05) than supervisors. Workers taking action tended to be younger and less experienced than other workers (p = 0.00). The final multivariate model showed those workers taking action were more likely to be mechanics and general laborers, to have experienced pain within the last week, to be involved in health and safety, to feel that changes aimed at reducing MSIs would be effective, and that injuries are due to adverse work conditions rather than with characteristics of individual workers. This information can be used to target ergonomics interventions in this industry.     

Approaches to picture perception: perceptual experience and ecological optics

"Pictorial perception" involves a kind of visual attention comparable to but not reducible to visual field and ways of experiencing the visual world. While all 3 are related to pictures and picturing, they are distinct, for picture perception has different purposes and effects than the other 2, including a kind of duality. Pictorial representation can also be approached via physics and "ecological optics" rather than types of experience, but there are serious conflicts between an experience approach and a physics approach, and these conflicts create difficulty in interpreting research results (e.g., in cross-cultural studies of pictorial perception). (French summary) (35 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An examination of the degrees of freedom of human jaw motion in speech and mastication

The kinematics of human jaw movements were assessed in terms of the three orientation angles and three positions that characterize the motion of the jaw as a rigid body. The analysis focused on the identification of the jaw's independent movement dimensions, and was based on an examination of jaw motion paths that were plotted in various combinations of linear and angular coordinate frames. Overall, both behaviors were characterized by independent motion in four degrees of freedom. In general, when jaw movements were plotted to show orientation in the sagittal plane as a function of horizontal position, relatively straight paths were observed. In speech, the slopes and intercepts of these paths varied depending on the phonetic material. The vertical position of the jaw was observed to shift up or down so as to displace the overall form of the sagittal plane motion path of the jaw. Yaw movements were small but independent of pitch, and vertical and horizontal position. In mastication, the slope and intercept of the relationship between pitch and horizontal position were affected by the type of food and its size. However, the range of variation was less than that observed in speech. When vertical jaw position was plotted as a function of horizontal position, the basic form of the path of the jaw was maintained but could be shifted vertically. In general, larger bolus diameters were associated with lower jaw positions throughout the movement. The timing of pitch and yaw motion differed. The most common pattern involved changes in pitch angle during jaw opening followed by a phase predominated by lateral motion (yaw). Thus, in both behaviors there was evidence of independent motion in pitch, yaw, horizontal position, and vertical position. This is consistent with the idea that motions in these degrees of freedom are independently controlled.     

Monitoring the mycotoxins in food and their biomarkers in the Czech Republic

Testing of the presence of toxigenic microfungi and mycotoxins in foodstuffs in the food chain is an important part of the food safety strategy in The Czech Republic. At the national level, control of their presence in the entire food chain is assured by Public Health Protection Agencies, by the Veterinary Administration and by the Czech Agriculture and Food Inspection Authority. This article summarizes surveillance activities of Public Health Protection Agencies and mycotoxins findings in dietary raw materials and foodstuffs from the 1990s to 2004 in the Czech Republic. At present, the health risk from the mycotoxins exposure from foodstuffs is assessed to be relatively low in the Czech Republic, especially as far as the foodstuffs of the Czech origin are concerned. It may result in late toxic effects (e. g., carcinogenic risk) following a single or repeated ingestion of low mycotoxins doses from foodstuffs. Nevertheless, the overall situation may change due to the globalization of the food market. In order to minimize the risk associated with mycotoxins and eliminate their impact on Czech public health, continuous monitoring of the presence of toxigenic moulds, mycotoxins, and their biomarkers is necessary, in conjunction with strict respect to European Union legislation.