Search

Background: Stress at workplace arises when the requirements for workers don’t meet their personal or social capabilities, or differ from the individual’s needs and motivation. Occupational stress is observed in a number of both elementary and high-tech occupational fields. In ferrous metallurgy it could be associated with 24/7 operating mode, high work intensity and a variety of unfavorable characteristics of working environment. The aim of the study is to clarify the nature of factors - stressors in ferrous metallurgy and to define ways for reduction of their negative health impact. Materials and Methods: Study subject are 91 workers in an electric steel-making department of a ferrous metallurgy enterprise in Bulgaria. Data, concerning working conditions, work characteristics, workers satisfaction, presence/absence of stress and chronic diseases, were collected by direct individual self-administered questionnaire and documents review. Results: Two of three study subjects reported stress related to their work. Noise, varies from 89.2 to 92.2 dB/A (at rate 85 dB/A) in different sections of the workshop, is the biggest stressor according to 77.5% of the investigated people, followed by short deadlines for task performance (46.5%) and ineffective leadership (32.4%). In addition, negative effects of stress is increasing by high dust levels, reaching up to 7 mg/m3 air at a standard of 6 mg/m3 air, and contain manganese, coke, chamotte, free and bound silica, rare metals, increased concentration of CO and more.Nevertheless workers consider that the organization provides measures for stress reduction by strict control on the limit values of noise, dust, temperature and chemicals (49.2%),provision of personal protective equipment establishment (69%) of a rational mode of work and rest (56.3%) and healthy eating (47.9%). Conclusions: Despite a plenty of environmental and organizational stressors, their negative effects could be decreased by appropriate preventive measures. Key messages: ) Factors-stressor in ferrous metallurgy could be associated with a variety of unfavorable characteristics of working environment,non-stop operating mode, high work intensity and poor time management. ) Noise is the biggest stressor followed by short deadlines for task performance and ineffective leadership. Stressors are modifiable and preventable by strict hygienic control and improved management. [ABSTRACT FROM AUTHOR]

Abstract: The increasing number of papers during the last years reveals an existence of effect of geophysical factors on human health. The subject of this paper is to present some results obtained confirming this effect and short review of some scientific opinions about mechanisms, according to which geomagnetic field (GMF) variations could influence on human. We have investigated the influence of geomagnetic disturbances on physiological parameters of healthy people as well as the relationship with dynamic of myocardial infarction. Although there are objective difficulties, investigations in that field will be extremely useful for protecting man from harmful effects of geophysical factors. [Copyright &y& Elsevier]

Abstract: The ability of the fungus Aspergillus awamori NRRL 3112 to degrade mixtures of some common phenolic compounds, namely phenol, catechol, 2,4-dichlorphenol and 2,6-dimethoxyphenol was investigated in the present study. For all combinations in which dichlorophenol was incorporated, it took equal time for the nearly complete degradation of the compound—4 days. Phenol was decomposed almost completely (99.5%) in a combination with dimethoxyphenol, to a lesser extent (88%) in a combination with catechol and to the least degree (25%) in the presence of 2,4-dichlorophenol. Catechol experienced a more substantial biotransformation (64%) when mixed with phenol and weaker (45%)—in a combination with dichlorophenol. 2,6-Dimethoxyphenol was better decomposed (69%) in mixtures containing phenol, while its biodegradation in a combination with 2,4-dichlorophenol was considerably poor (only 5%). [Copyright &y& Elsevier]

Abstract: The antioxidant effect and the total phenols of ginger extract were studied. The total phenols of the alcohol extract were found to be 870.1mg/g dry extract. 2,2-Diphenyl-1-picril hydrazyl radical (DPPH) scavenging reached 90.1% and exceeded that of butylated hydroxytoluene (BHT), the IC50 concentration for inhibition of DPPH was 0.64μg/ml. The antioxidant activity in a linoleic acid/water emulsion system determined by means of thiobarbituric acid reactive substances (TBARS) was highest at 37°C – 73.2%, and 71.6% when the formation of conjugated dienes was inhibited. At 80°C the antioxidant activity at the highest concentration of a ginger extract was less efficient: 65.7% for conjugated dienes formation and 68.2% for TBARS. The ginger extract inhibited the hydroxyl radicals 79.6% at 37°C and 74.8% at 80°C, which showed a higher antioxidant activity than quercetin. The IC50 concentration for inhibiting OH at 37°C was slower than that at 80°C – 1.90 and 2.78μg/ml, respectively. The ginger extract chelated Fe3+ in the solution. [Copyright &y& Elsevier]

Abstract: This collaborative study is based on the analysis and comparison of results of coordinated experimental investigations conducted in Bulgaria and Azerbaijan for revealing a possible influence of solar activity changes and related geomagnetic activity variations on the human cardio-vascular state. Arterial blood pressure and heart rate of 86 healthy volunteers were measured on working days during a period of comparatively high solar and geomagnetic activity (2799 measurements in autumn 2001 and spring 2002) in Sofia. Daily experimental investigations of parameters of cardio-vascular health state were performed in Azerbaijan with a permanent group of examined persons. Heart rate and electrocardiograms were digitally registered (in total 1532 records) for seven functionally healthy persons on working days and Saturdays, in the Laboratory of Heliobiology at the Medical Center INAM in Baku, from 15.07.2006 to 13.11.2007. Obtained digital recordings were subjected to medical, statistical and spectral analyses. Special attention was paid to effects of solar extreme events, particularly those of November 2001 and December 2006. The statistical method of the analysis of variance (ANOVA) and post hoc analysis were applied to check the significance of the influence of geomagnetic activity on the cardio-vascular parameters under consideration. Results revealed statistically significant increments for the mean systolic and diastolic blood pressure values of the group with geomagnetic activity increase. Arterial blood pressure values started increasing two days prior to geomagnetic storms and kept their high values up to two days after the storms. Heart rate reaction was ambiguous and not significant for healthy persons examined (for both groups) under conditions with geomagnetic activity changes. It is concluded that heart rate for healthy persons at middle latitudes can be considered as a more stable physiological parameter which is not so sensitive to environmental changes while the dynamics of arterial blood pressure reveals a compensatory reaction of the human organism for adaptation. [Copyright &y& Elsevier]

Trametes versicolor 1 was shown to grow on phenol as its sole carbon and energy source. The culture growth and degradation ability dependence on culture medium pH value was observed. The optimal pH value of a liquid Czapek salt medium was 6.5. The investigated strain utilized completely 0.5 g/l phenol in 6 days. The dynamics of the phenol degradation process was investigated. The process was characterized by specific growth rate μmax 0.33 h−1, metabolic coefficient k = 4.4, yield coefficient Y x/ s = 0.23 and rate of degradation Q = 0.506 h−1. The intracellular activities of phenol hydroxylase (0.333 U/mg protein) and cis, cis-muconate lactonizing enzyme (0.41 U/mg protein) were demonstrated for the first time in this fungus. In an attempt to estimate the occurrence of gene sequences in T. versicolor 1 related to phenol degradation pathway a dot blot analysis with total DNA isolated from this strain was performed. Two synthetic oligonucleotides were used as hybridizing probes. One of the probes was homologous to the 5′end of phyA gene coding for phenol hydroxylase in Trichosporon cutaneum ATCC 46490. The other probe was created on the basis of cis, cis-muconate lactonizing enzyme coding gene in T. cutaneum ATCC 58094. The results of these investigations showed that T. versicolor 1 may carry genes similar to those of Trichosporon cutaneum capable to degrade phenol. [ABSTRACT FROM AUTHOR]