Spatio-temporal variability of solid, total dissolved and labile metal: passive vs. discrete sampling evaluation in river metal monitoring

In order to obtain representative dissolved and solid samples from the aquatic environment, a spectrum of sampling methods are available, each one with different advantages and drawbacks. This article evaluates the use of discrete sampling and time-integrated sampling in illustrating medium-term spatial and temporal variation. Discrete concentration index (CI) calculated as the ratio between dissolved and solid metal concentrations in grab samples are compared with time-integrated concentration index (CI) calculated from suspended particulate matter (SPM) collected in sediment traps and labile metals measured by the diffusive gel in thin films (DGT) method, collected once a month during one year at the Seine River, upstream and downstream of the Greater Paris Region. Discrete CI at Bougival was found to be significantly higher than at Triel for Co, Cu, Mn, Ni and Zn, while discrete metal partitioning at Marnay was found to be similar to Bougival and Triel. However, when using time-integrated CI, not only was Bougival CI significantly higher than Triel CI, CI at Marnay was also found to be significantly higher than CI at Triel which was not observed for discrete CI values. Since values are time-averaged, dramatic fluctuations were smoothed out and significant medium-term trends were enhanced. As a result, time-integrated concentration index (CI) was able to better illustrate urbanization impact between sites when compared to discrete CI. The impact of significant seasonal phenomenon such as winter flood, low flow and redox cycles was also, to a certain extent, visible in time-integrated CI values at the upstream site. The use of time-integrated concentration index may be useful for medium- to long-term metal studies in the aquatic environment.     

Fungal DNA and pet allergen levels in Swedish day care centers and associations with building characteristics

Pet allergens and mold growth related to damp are common phenomena in day care centers in Sweden but exposure measurements of these factors are lacking. The aim of this study was to investigate the relationship between building construction and indoor environment quality in Swedish day care centers and the potential for exposure to fungi (analyzed by quantitative PCR) and animal allergens (analyzed by ELISA). Measurements were performed in 21 day care centers (103 rooms) from one municipality in Sweden, which were identified as constructions at risk of dampness (85% of the buildings) and with visible damage and mold growth (54% of the buildings). Dust samples were collected using cotton swab and Petri dishes. Total fungal DNA was detected in 99% and 100%, Aspergillus/Penicillium DNA in 54% and 68%, and Stachybotrys chartarum DNA in 4% and 9% of the investigated rooms in cotton swab and Petri dish samples, respectively. The total fungal DNA levels (Geometric Mean, GM) were 4.2 × 10(6) cell equivalents per m(2) and 2.9 × 10(5) cell equivalents per m(2) per day in the swab and Petri dish samples, respectively. The concentrations (GM) of cat (Fel d1), dog (Can f1), and horse (Equ cx) allergens were 9.4, 7.2 ng m(-2) day(-1), and 5.0 unit per m(2) per day, respectively. Total fungal DNA levels were higher in risk construction buildings (p = 0.01), in rooms with linoleum flooring material (p = 0.003), and in buildings with rotating heat exchangers (p = 0.02). There were associations between total fungal DNA levels and cat (p = 0.02), dog (p < 0.001), and horse (p = 0.001) allergens. In conclusion, risk constructions, damp constructions, mould growth, fungal DNA, and animal allergens were common exposure factors in Swedish day care centers. Building constructions that represent a high risk for internal dampness should be avoided in the future, and measures to reduce allergen levels should be considered to protect pet-allergic children from asthmatic problems.     

Algal blooms decrease care but increase egg survival in a fish with paternal care

Human-induced eutrophication, resulting in algal blooms and increased water turbidity, is an alarming problem in aquatic systems. Here, we experimentally tested the impact of algal turbidity on parental care, egg fanning, and time in the nest, in the sand goby, Pomatoschistus minutus, a fish with uniparental male care. We allowed males to care for their eggs in either clear water or water made turbid by planktonic algae. In the early brood cycle, males fanned their eggs less in turbid than in clear water, but this difference disappeared later. Despite decreased care, egg survival was higher in turbid conditions, indicating that early fanning may partly be redundant for egg survival and perhaps used more as courtship. Males also spent more time out of their nest in turbid water, perhaps as a means to encounter additional females under conditions of low visibility.     

Determination of the minimum ignition energy on the basis of a statistical approach

Based on existing MIE test results and new measurements, a statistical analysis for the MIE of hydrogen, ethene and propane is made by means of the logistic regression. The conditions necessary to carry out such an approach are discussed. It is shown that MIE values which are connected with a certain ignition probability could be determined adequately and lead to a more sophisticated result, also with regard to measurement uncertainties. This, in turn, leads to a better comparability and a higher informative content. At the same time, the MIEs of hydrogen, ethene and propane are reviewed. In doing so, a useful contribution to the discussion concerning the MIE of propane is made.     

Application of a Screening Method in Assessing Occupational Safety and Health of Computer Workstations

Employers and workers need concrete guidance to plan and implement changes in the ergonomics of computer workstations. The Näppärä method is a screening tool for identifying problems requiring further assessment and corrective actions. The aim of this study was to assess the work of occupational safety and health (OSH) government inspectors who used Näppärä as part of their OSH enforcement inspections (430 assessments) related to computer work. The modifications in workstation ergonomics involved mainly adjustments to the screen, mouse, keyboard, forearm supports, and chair. One output of the assessment is an index indicating the percentage of compliance items. This method can be considered as exposure assessment and ergonomics intervention used as a benchmark for the level of ergonomics. Future research can examine whether the effectiveness of participatory ergonomics interventions should be investigated with Näppärä.     

A New Approach to Measuring Work-Related Well-Being

The main aim of this study was to develop a short questionnaire to assess work-related well-being from the organizational behaviour perspective. The short well-being questionnaire enables measuring longitudinal work-related well-being. Work-related well-being was assessed with a 147-item questionnaire covering both organizational and intrinsic factors of work-related well-being. The questionnaire consisted of 27 categories. The respondents were 114 women (65%) and 62 men (35%), mean age 39.2 years, in various occupations. From the extensive questionnaire a shorter questionnaire with 33 items was developed by principal component analysis. The Kaiser-Meyer-Olkin measure to test the sampling adequacy of 27 factor solutions varied from .62 to .91 and Cronbach’s a was .74–.94. Most K values of the shorter questionnaire were .50–.94 (p < .001). The reliability of the short version was comparable to that of the original questionnaire. The short one could also be suitable for Internet and mobile questionnaire applications.     

Community Sustainability Plans to enable change towards sustainable practice – a Scottish case study

There is a need for a global shift towards a low-carbon society and this requires action at the local level. The aim of the study into sustainable community development is to clarify the role of a community as a whole rather than the role of individuals within that community. Mixed methods of literature review and empirical study have been used to translate the knowledge and experience with urban sustainable development into empirical knowledge of a rural, market town setting. The exemplary case study is the Scottish market town Huntly. The main findings of the study show the need for three ingredients for a Community Sustainability Plan for a town such as Huntly. Community involvement is crucial in developing such plans in a rural setting. Further research in more remote settings, e.g. coastal and island communities, is needed to allow broader conclusions on rural sustainable development.