A fuzzy model for assessing risk of occupational safety in the processing industry

Managing occupational safety in any kind of industry, especially in processing, is very important and complex. This paper develops a new method for occupational risk assessment in the presence of uncertainties. Uncertain values of hazardous factors and consequence frequencies are described with linguistic expressions defined by a safety management team. They are modeled with fuzzy sets. Consequence severities depend on current hazardous factors, and their values are calculated with the proposed procedure. The proposed model is tested with real-life data from fruit processing firms in Central Serbia.     

Physiological testing of Mytilus galloprovincialis for the environmental assessing of coastal marine areas: a case study in Boka Kotorska Bay (the Adriatic Sea)

The aim of this work was to validate in the field certain measurement of the heart rate alterations of the bioindicator organism Mytilus galloprovicialis as a tool for ecotoxicological biomonitoring and assessment applications related to coastal and marine environment. The latter was determined by testing the mussels according to the method of functional loading (1-hour lowered salinity stress-exposure). The time of heart rate (HR) recovery (T_rec) and the coefficient of HR variation (CV_HR) in a group of tested animals were used as biomarkers for the assessment of their physiological state. It was found that the values of the biomarkers in mussels from our reference location were 1.3-1.5 times lower than in mussels from differently polluted coastal areas of the Bay. The study also included an investigation of the relationship between the mussel’s cardiac rhythm characteristics and the bioaccumulation of trace elements in their soft tissues, caused by chronic pollution. The conclusion was drawn that this approach to the physiological testing of mussels could be useful in developing a rapid and low-cost method for the assessment of the health of coastal ecosystems.     

Influence of static magnetic fields on nerve regeneration in vitro

Our research involves determining how non-invasive electric and magnetic fields influence neuronal growth in vitro. In previous studies we have shown that pulsed electromagnetic fields (PEMF) as well as direct current (DC) alone stimulate neurite outgrowth from dorsal root ganglion explants [Sisken et al. 1984; Sisken et al. (Restor Neurol Neurosci 1:303–309, 1990); Greenebaum et al. (Bioelectromagnetics 17:293–302, 1996)]. A maximum response was obtained when nerve growth factor (NGF) was also present in the medium. The results of our experiments using static magnetic fields of different strengths are presented below and indicate that fields of high magnetic strength (450–900 gauss) with added NGF stimulate neurite outgrowth comparable to the response obtained with PEMF plus NGF.     

Bioluminescent yeast assays for detecting estrogenic and androgenic activity in different matrices

In this paper we describe the construction and use of a set of bioluminescent yeast strains for the detection of compounds that can affect androgen or estrogen receptor mediated hormonal signalling. The set includes Saccharomyces cerevisiae strains expressing human androgen receptor (AR), estrogen receptor alpha (ERalpha) or estrogen receptor beta (ERbeta), along with firefly luciferase controlled by a respective hormone responsive promoter. A constitutively luminescent strain was included in the set for determining the cytotoxicity of the sample. Yeast cells were incubated with pure chemicals or complex samples for 2.5 h, after which the signal could be detected from the cell-sample mixture after simply adding the D-luciferin substrate. The assays could be completed in one day and they required no cell lysis or centrifugation steps, which makes them suitable for high-throughput analysis of samples. Due to a short incubation time the assays are directly applicable to different sample matrices, requiring no pretreatment of the samples. The assays were used to assess the hormonal activity in moisturizing lotions as an example of a complex sample matrix known to contain endocrine disrupting chemicals. Six out of eight tested moisturisers showed high estrogenic activity, whereas no androgenic activity was observed in the samples.     

Impact of aquacultures on the marine ecosystem: Modelling benthic carbon loading over variable depth

In order to be used within Environmental Impact Assessment study, we have developed a three-dimensional particle tracking model for prediction of benthic carbon loading (BCL) caused by fish farms. The model is based on stochastic differential equations for particle transport consistent with the well-known semi-empirical advection/diffusion equation. It requires only easily obtainable input data in the form of measured current record, the source location and a specification of local bathymetry. The model accounts for advection by long-term residual and tidal currents, turbulent diffusion, realistic bathymetry and variations in daily (monthly or yearly) emissions from fish farm.Here, we concentrate on the changes in sedimentation pattern caused by various bathymetric shapes. Examination of idealized cases reveals where and why we can expect the worst impact on benthic communities. For future reference, these results will be included into guidelines for fish farming.     

Transport and Diffusion of Ozone in the Nocturnal and Morning Planetary Boundary Layer of the Phoenix Valley

The evolution of ozone (O ₃) in the nocturnal and morning-transitional planetary boundary layer (PBL) of the Phoenix valley was measured as a part of the `Phoenix Sunrise Experiment 2001' of the U.S. Department of Energy conducted in June 2001. The goal of the field program was to study the transport, distribution and storage of ozone and its precursors in the urban boundary layer over a diurnal cycle. The ground level O <sub>3</sub> as well as mean meteorological variables and turbulence were measured over the entire period, and vertical profiling (using a tethered balloon) was made during the morning transition period. Approximately half of the observational days showed the usual diurnal cycle of high O <sub>3</sub> during the day and low O <sub>3</sub> at night, with nitrogen oxides (NO <sub>x</sub> = NO <sub>2</sub> + NO) showing an out of phase relationship with O <sub>3</sub>. The rest of the days were signified by an anomalous increase of O <sub>3</sub> in the late evening ( 2200 LST), concomitant with a sudden drop of temperature, an enhancement of wind speed and Reynolds stresses, a positive heat flux and a change of wind direction. NO <sub>x</sub> measurements indicated the simultaneous arrival of an `aged' air mass, which was corroborated by the wind predictions of a mesoscale numerical model. In all, the results indicate that the recirculation of O ₃ rich air masses is responsible for the said high-O ₃ events. Such air masses are produced during the transport of O ₃ precursors by the upslope flow toward mountainous suburbs during the day, and they return back to the city at night via downslope winds (i.e. mountain breeze). The corresponding flow patterns, and hence the high-O ₃ events, are determined by background meteorological conditions. The vertical profiling of O ₃ and flow variables during the morning transition points to a myriad of transport, mixing and chemical processes that determine the fate of tropospheric O ₃. How well such processes are incorporated and resolved in predictive O ₃ models should determine the accuracy of their predictions.     

Predicting aquaculture-derived benthic organic enrichment: Model validation

A sediment trap validation study was conducted near the commercial sea bass and sea bream fish farm in order to assess the predictive capability of a particle tracking deposition model. The validation procedure consisted of two distinct phases. First, the deposition of particulate waste (i.e. fecal pellets and excess feed) was measured near a single net pen containing 19 tons of sea bass. Afterwards, the model quality was determined by statistical comparison of predicted and observed values.Goodness of fit analysis indicates that the model successfully accounts for more than 75% of variance in the observed deposition. At 5% significance level, predictions do not underestimate or overestimate observations and there is no bias. Mean absolute relative error of ±48.9% compares favorably to other published deposition models. Obtained results affirm the reliability of particle tracking techniques in modeling the aquaculture-derived benthic organic enrichment.     

Natural radionuclides in trees grown on a uranium mill tailings waste pile

Objective  

The purpose of the study was to investigate natural radionuclide uptake and allocation by trees.     

Assessing the effects of domestic and international energy scenarios and emission reduction strategies on acidification in Finland

An integrated model system was developed and used to assess the effects of alternative energy production scenarios and reduction policies on acidification of lakes and forest soils in Finland. The analysis covered different energy scenarios and resulting emissions of sulfur oxides and nitrogen oxides in Finland, as well as ammonia emissions with various control requirements. In addition, emission reduction scenarios of varied ambition levels in the bordering areas of Finland and in other parts of Europe were included in the analysis. The impacts of the different scenarios were quantified with exceedances of critical loads for acidification and with the total areas where the critical loads are exceeded. The possibilities for reducing the areas with critical load exceedances with national or bilateral measures were investigated. The differences in areas at risk, if depositions from domestic and nearby sources are estimated with a regional model and point-source databases or with a continental scale model and coarser-scale emission data, were analyzed. The reasons for the differences and the implications for national-level assessment are discussed.