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111.
Ecotoxicological effects associated with contaminants present in dredged material from Spain were determined using a marine biotest based on the determination of metallothionein-like-protein concentrations (MTLPs) in the shore crab Carcinus maenas. Intermoult female C. maenas were exposed in the laboratory to sediments from three Spanish ports, Ría de Huelva (SW, Spain), La Coru?a (NW, Spain) and Bahía de Cádiz (SW, Spain) per replicate during 21 days. Hepatopancreas samples from crabs were taken for metallothioneins analysis on days 0, 7 and 21. Furthermore, chemical analysis was performed in the stations to determine the degree and nature of sediment contamination (Cr, Ni, Cu, Zn, Cd, Pb, Hg, As, PAHs and PCBs). A significant increase (p<0.05) in metallothionein concentration was observed over time in individuals exposed to sediment from the port Ría de Huelva characterized by high concentrations of metals. A toxicokinetic approach is proposed in this study related to the use of this biomarker in C. maenas to evaluate bioavailability associated with metals present in dredged material. As a first step, this toxicokinetic approach might reveal as a sensitive tool for evaluating bioavailability of contaminants present in dredged material.  相似文献   
112.
Insects have been used as models for understanding animal orientation. It is well accepted that social insects such as honeybees and ants use different natural cues in their orientation mechanism. A magnetic sensitivity was suggested for the stingless bee Schwarziana quadripunctata, based on the observation of a surprising effect of a geomagnetic storm on the nest-exiting flight angles. Stimulated by this result, in this paper, the effects of a time-compressed simulated geomagnetic storm (TC-SGS) on the nest-exiting flight angles of another stingless bee, Tetragonisca angustula, are presented. Under an applied SGS, either on the horizontal or vertical component of the geomagnetic field, both nest-exiting flight angles, dip and azimuth, are statistically different from those under geomagnetic conditions. The angular dependence of ferromagnetic resonance (FMR) spectra of whole stingless bees shows the presence of organized magnetic nanoparticles in their bodies, which indicates this material as a possible magnetic detector.  相似文献   
113.
The sensilla of insects are integumental units that play a role as sensory structures and are crucial for the perception of stimuli and for communication. In this study, we compared the antennal sensilla of females (workers and queens), males (haploid (n) and diploid (2n)), and queen-like males (QLMs, resulting from 2n males after juvenile hormone (JH) treatment) in the stingless bee Melipona quadrifasciata. Images of the dorsal antenna surfaces were acquired using a scanning electron microscope. As reported for other hymenopterans, this species exhibits a heterogeneous sensillar distribution along the antennae. Thirteen different types of sensilla were found in the antennae of M. quadrifasciata: trichodea (subtypes I to VI), chaetica (subtypes I and II), placodea, basiconica, ampullacea, coeloconica, and coelocapitula. Sensilla trichodea I were the most abundant, followed by sensilla placodea, which might function in olfactory perception. Sensilla basiconica, sensilla chaetica I, sensilla coeloconica, and sensilla ampullacea were found exclusively in females. In terms of the composition and size of the sensilla, the antennae of QLMs most closely resemble those of the 2n male, although QLMs exhibit a queen phenotype. This study represents the first comparative analysis of the antennal sensilla of M. quadrifasciata. The differences found in the type and amount of sensilla between the castes and sexes are discussed based on the presumed sensillary functions.  相似文献   
114.
115.
Flower symmetry is considered a species-specific trait and is categorized in asymmetry, actinomorphic symmetry, bisymmetry and zygomorphic symmetry. Here we report on the intra-individual variation of flower symmetry in the genus Saxifraga and the influence of light, gravity and intrinsic factors on the development of flower symmetry. We tested five species—Saxifraga cuneifolia, Saxifraga imparilis, Saxifraga rotundifolia, Saxifraga stolonifera and Saxifraga umbrosa—concerning six flower parameters—angles between petals, petal length, petal pigmentation, angular position of carpels, movement of stamens and (only for S. imparilis and S. stolonifera) the length of the two lower elongated petals in regard to their position towards the stem. Specimens of all species were tested on a vertical clinostat as a gravity compensator, on a horizontal clinostat as a light incidence compensator and on a stationary control. The results show that the angle of incident light has no apparent impact on flower symmetry, whereas gravity affects the angular position of petals in S. cuneifolia and S. umbrosa and the petal colouration in S. rotundifolia. In S. cuneifolia and S. umbrosa, the absence of directional gravity resulted in the development of actinomorphic flowers, whereas the corresponding control flowers were zygomorphic. The development of flowers in S. rotundifolia was not altered by this treatment. The length of the two elongated petals in S. stolonifera and S. imparilis was not affected by gravity, but rather was determined by position of the flower within the inflorescence and resulted in asymmetrical flowers.  相似文献   
116.
Sustainable product development is closely related to sustainable consumption. The understanding of consumers' purchase, use and discard behaviours may facilitate the identification of requirements to guide manufacturers in the development of sustainable goods and services. The aim of this paper is to investigate consumers' perception about factors that motivate or discourage the consumption of sustainable products to identify demands and convert them into requirements. South Brazilian green and traditional consumers were asked to complete an exploratory qualitative questionnaire. Their answers were organized and compared to identify differences and similarities between the demands of these two groups. Furthermore, demands were converted into requirements for packages, products, manufactures, stores planning and discard systems. The interpretation of factors that motivate or discourage the purchase of sustainable products given by interviewees led to the creation of a list of possible public policies or programmes, aiming to support sustainable consumption. The results demonstrate the necessity of further quantitative investigation between consumer groups, for validation purposes.  相似文献   
117.
118.
The results of an inter-laboratory comparison exercise to determine cytostatic anticancer drug residues in surface water, hospital wastewater and wastewater treatment plant effluent are reported. To obtain a critical number of participants, an invitation was sent out to potential laboratories identified to have the necessary knowledge and instrumentation. Nine laboratories worldwide confirmed their participation in the exercise. The compounds selected (based on the extent of use and laboratories capabilities) included cyclophosphamide, ifosfamide, 5-fluorouracil, gemcitabine, etoposide, methotrexate and cisplatinum. Samples of spiked waste (hospital and wastewater treatment plant effluent) and surface water, and additional non-spiked hospital wastewater, were prepared by the organising laboratory (Jo?ef Stefan Institute) and sent out to each participant partner for analysis. All analytical methods included solid phase extraction (SPE) and the use of surrogate/internal standards for quantification. Chemical analysis was performed using either liquid or gas chromatography mass (MS) or tandem mass (MS/MS) spectrometry. Cisplatinum was determined using inductively coupled plasma mass spectrometry (ICP-MS). A required minimum contribution of five laboratories meant that only cyclophosphamide, ifosfamide, methotrexate and etoposide could be included in the statistical evaluation. z-score and Q test revealed 3 and 4 outliers using classical and robust approach, respectively. The smallest absolute differences between the spiked values and the measured values were observed in the surface water matrix. The highest within-laboratory repeatability was observed for methotrexate in all three matrices (CV?≤?12 %). Overall, inter-laboratory reproducibility was poor for all compounds and matrices (CV 27–143 %) with the only exception being methotrexate measured in the spiked hospital wastewater (CV?=?8 %). Random and total errors were identified by means of Youden plots.  相似文献   
119.
In order to assess indoor air quality (IAQ), two 1-week monitoring campaigns of volatile organic compounds (VOC) were performed in different areas of a multistorey shopping mall. High-spatial-resolution monitoring was conducted at 32 indoor sites located in two storehouses and in different departments of a supermarket. At the same time, VOC concentrations were monitored in the mall and parking lot area as well as outdoors. VOC were sampled at 48-h periods using diffusive samplers suitable for thermal desorption. The samples were then analyzed with gas chromatography–mass spectrometry (GC–MS). The data analysis and chromatic maps indicated that the two storehouses had the highest VOC concentrations consisting principally of terpenes. These higher TVOC concentrations could be a result of the low efficiency of the air exchange and intake systems, as well as the large quantity of articles stored in these small spaces. Instead, inside the supermarket, the food department was the most critical area for VOC concentrations. To identify potential emission sources in this department, a continuous VOC analyzer was used. The findings indicated that the highest total VOC concentrations were present during cleaning activities and that these activities were carried out frequently in the food department. The study highlights the importance of conducting both high-spatial-resolution monitoring and high-temporal-resolution monitoring. The former was able to identify critical issues in environments with a complex emission scenario while the latter was useful in interpreting the dynamics of each emission source.  相似文献   
120.
Because of their excellent properties as a biomonitor, yellow eels (Anguilla anguilla) have been used for time-trend monitoring of polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) and tetrabrominated diphenylether (tetra-BDE). The program has now lasted for thirty years and has delivered valuable information on trends and spatial differences of these compounds in the delta of the rivers Rhine and Meuse and other Dutch canals, rivers and lakes. Specific local PCB, HCH and dieldrin contaminations were identified. Temporal trends show a slow decrease of PCB concentrations since 1977. Eels from the rivers Rhine and Meuse still exceed present European maximum residue limits for dioxin-like PCBs. Apart from some exceptions, OCP and tetra-BDE concentrations have also decreased, and more than those of PCBs. Fat contents of eel have decreased from an average of 21 to ca. 13%. This decrease in fat contents, coincides with the strong reduction of the European eel stock.  相似文献   
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