The effect of long-term exposure to high frequency electromagnetic field (HF EMF) on some somatic and neural characteristics
was studied in neurodefective Lurcher mutant (+/Lc) and normal wild type mice (+/+). Both newborn and young adult (3 months)
animals derived from two strains (C3H, B6CBA) were exposed to HF EMF (870 MHz) from 1st to 21st day or from 91st to 120th
day respectively. In animals of both groups and controls we observed the development of body weight. Moreover, in the HF EMF
exposed adult B6CBA animals we studied spatial learning ability, motor functions and the CNS excitability. To investigate
specific energy absorption rate (SAR) in experimental animals we have done the basic 3D calculations of the electromagnetic
energy distribution in the simplified model of the mouse. The HF EMF exposed animals exhibited mild differences of body weight
between them and unexposed controls. The long-term exposure to HF EMF did not significantly influence the ability to learn
in the Morris water maze. However, significant lower swimming speed was found in the irradiated +/Lc as well as lower motor
activity of +/+ in the open field when compared to controls. No significant differences were found between HF EMF irradiated
animals and controls in examination of the CNS excitability and motor functions. 相似文献
Geochemical, mineralogical and sedimentological analyses were carried out to contrast two different sites (respectively characterized
by permanently oxic and anoxic conditions) in a small, meromictic, seawater lake. In fact, due to relatively high organic
matter content, and reduced water exchange, the Rogoznica Lake has almost permanent anoxic conditions below the depth of 12 m,
where sediment can be considered an anoxic–sulphidic sedimentary environment. Different water column and sediments redox conditions
affect the distribution and speciation of major redox-sensitive metals (Fe, Mn, Mo), reduced sulphur species (RSS) and dissolved
organic C (DOC). Trace metals, especially those that accumulate in anoxic–sulphidic environments (Fe, Mo) showed a marked
enrichment in the solid phase, whereas the low solubility of sulphides leads to low porewater concentrations. The relatively
high sedimentary enrichment of Mo (up to 81 mg/kg) also confirms highly anoxic conditions within the Rogoznica Lake sediments.
Results clearly show that chemical species within the sediments will tend towards equilibrium between porewater and solid
phase according the prevailing environment conditions such as redox, pH, salinity, DOC. 相似文献
Journal of Material Cycles and Waste Management - Recycling possibilities were evaluated for a composite waste composed of glass fiber reinforced polyester bound to a layer of crosslinked... 相似文献
The architecture of vertical aerial orb webs may be affected by spider size and gravity or by the available web space, in
addition to phylogenetic and/or developmental factors. Vertical orb web asymmetry measured by hub displacement has been shown
to increase in bigger and heavier spiders; however, previous studies have mostly focused on adult and subadult spiders or
on several size classes with measured size parameters but no mass. Both estimations are suboptimal because (1) adult orb web
spiders may not invest heavily in optimal web construction, whereas juveniles do; (2) size class/developmental stage is difficult
to estimate in the field and is thus subjective, and (3) mass scales differently to size and is therefore more important in
predicting aerial foraging success due to gravity. We studied vertical web asymmetry in a giant orb web spider, Nephila pilipes, across a wide range of size classes/developmental stages and tested the hypothesis that vertical web asymmetry (measured
as hub displacement) is affected by gravity. On a sample of 100 webs, we found that hubs were more displaced in heavier and
larger juveniles and that spider mass explained vertical web asymmetry better than other measures of spider size (carapace
and leg lengths, developmental stage). Quantifying web shape via the ladder index suggested that, unlike in other nephilid
taxa, growing Nephila orbs do not become vertically elongated. We conclude that the ontogenetic pattern of progressive vertical web asymmetry in
Nephila can be explained by optimal foraging due to gravity, to which the opposing selective force may be high web-building costs
in the lower orb. Recent literature finds little support for alternative explanations of ontogenetic orb web allometry such
as the size limitation hypothesis and the biogenetic law. 相似文献
The feasibility of modeling municipal waste generation (MWG) for countries at different levels of development using artificial neural networks (ANN) and selected generic indicators of sustainability was investigated. The main goals of this research were to develop ANN-based models for predicting MWG, to overcome the problem of incomplete MWG data, which is notable in developing countries, and to provide a new method for the planning of municipal solid waste management systems as well as for the simulation of various other scenarios. Data from 26 European countries was used in this study as training, test and validation datasets for the developing of ANN models. Since this kind of modeling is particularly important for developing countries where MWG data is missing or incomplete, emphasis was placed on modeling of MWG for Bulgaria and Serbia. Based on a comparison of actual MWG data with predictions given by the model, we show that ANNs can be applied successfully to modeling and forecasting MWG on a national scale. Moreover, the scope for possible application of the model is broad, since it uses generic indicators of sustainability such as gross domestic product, domestic material consumption and resource productivity, and performs well for countries with highly diversified levels of economic development, industrial structure, productivity and output. 相似文献
Bacteria from the genus Shewanella are inhabitants of marine and freshwater ecosystems, recognized fish spoilage bacteria, but less known as fish disease agents. Shewanella spp. isolated from fish living in waters close to effluents of a wastewater treatment plant (WWTP) were not previously characterized. We have tested Shewanella isolates from WWTP-affected waters and related fish. Genotypic characterization identified most strains as S. baltica and S. oneidensis. In order to investigate the sensibility and accuracy of their MALDI-TOF MS identification, they were grown on two culture media enriched by various NaCl concentrations, incubated at different temperatures and duration. We analyzed their antimicrobial susceptibility on a panel of antimicrobial drugs and capacity for biofilm production. With a view to demonstrate their capacity to produce fatty acids, we assessed the impact of different culture media on their lipid profile. We performed zebrafish embryotoxicity tests to simulate the environmental infection of the earliest life stages in S. baltica-contaminated waters. The best MALDI-TOF MS identification scores were for strains cultivated on TSA for 24 h at 22 °C and with supplementation of 1.5% NaCl. Less than 17% of isolates demonstrated antimicrobial resistance. Most isolates were weak biofilm producers. Strain-to-strain variation of MIC and MBC was low. The major fatty acids were C15:0, C16:0, C16:1, C17:1, and iC15:0. Exposure of Danio rerio to different S. baltica concentrations induced severe effects on zebrafish development: decreased heartbeat rate, locomotor activity, and melanin pigmentation. S. baltica passed through chorionic pores of zebrafish.
Environmental Science and Pollution Research - The consumption of hazardous antineoplastic drugs (ADs) used in anticancer chemotherapies is steadily increasing representing thus risks to both human... 相似文献
Many studies explore the feasibility of co-existence between genetically modified (GM) and conventional (non-GM) crops. An important research topic in these studies is the process of outcrossing, i.e., the process of gene flow via pollen flow from GM to non-GM crops. In this paper, we address a new modelling approach to define the environmentally driven processes of outcrossing for maize from existing empirical datasets. In particular, we use equation discovery methodology that combines background knowledge and empirical data from several studies. We induce models that predict the degree of outcrossing rate between the donor (GM) and the recipient (non-GM) maize field from the distance between the fields and the local wind characteristics (speed, direction and duration). This results in highly accurate models, for which both variables (distance and wind) are essential and of roughly equal importance. 相似文献