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151.
Alvarez-Muñoz D Lara-Martín PA Blasco J Gómez-Parra A González-Mazo E 《Environment international》2007,33(4):565-570
The presence of linear alkylbenzene sulfonates (LAS) and their degradation intermediates, sulfophenylcarboxylic acids (SPCs), with concentrations up to 100 ppb has been found in surface waters taken from the estuary of the river Guadalete (Cádiz, SW of Spain). Higher concentrations were found at the sampling site located adjacent to the discharge outlet of a wastewater treatment plant (WWTP). The concentrations decreased downstream to a few ppb as a result of dilution, sorption, and degradation processes, which were taking place along the estuary. Once the presence of both xenobiotics was confirmed in the environment, an in vivo assay was conducted to study their biotransformation and effects in the benthic fish Solea senegalensis. A flow-through system was employed, consisting of an exposure phase (120 h) with environmental levels of the surfactant (200, 500 and 800 microg/L of 2?C(10)LAS), followed by a depuration stage (72 h). The generation of SPCs has been quantified during these phases in both water and fish, with LAS biotransformation shown in all cases. The antioxidant enzymes catalase (CAT), glutathione peroxidase (GPX), glutathione reductase (GR), the phase II enzyme glutathione S-transferase (GST), and the phase III acid and alkaline phosphatases (AcP, ALP) were also estimated and utilized as biomarkers. 相似文献
152.
Martín-Díaz ML Kalman J Riba I de la Reguera DF Blasco J DelValls A 《Environment international》2007,33(4):463-468
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
153.
Mariela C. Castro Alfredo A. Carlini Rodolfo Sánchez Marcelo R. Sánchez-Villagra 《Die Naturwissenschaften》2014,101(2):77-86
We describe Pliodasypus vergelianus gen. et sp. nov., a Dasypodini armadillo from the middle Pliocene of Venezuela (Vergel Member, San Gregorio Formation). Although scarce, the remains are remarkable because of their geochronologic proximity to the main phase of Great American Biotic Interchange (GABI). The cladistic analysis conducted reveals that Pliodasypus groups with Dasypus and both are sister taxa of Propraopus, whereas Anadasypus is at a basal position. With respect to the records of tribe Dasypodini, after its oldest representative (Anadasypus, middle and late Miocene), the chronologically subsequent form is Pl. vergelianus (middle Pliocene), followed by Dasypus bellus in higher northern latitudes (late Pliocene), and then by widespread occurrences in the Pleistocene of North America (D. bellus) and South America (Propraopus, Dasypus punctatus, and Dasypus novemcinctus). Thus, we infer that Dasypus differentiated in the late Pliocene at low latitudes in the northern South America. It leads to two alternative hypotheses of dispersal: (a) some early Dasypus remained cryptically in South America until the Pleistocene, whereas others dispersed to North America between 2.2 and 2.7 Ma, or (b) they dispersed to North America subsequently to the emersion of the Panamanian isthmus and D. bellus differentiated there; later, during the Pleistocene, D. bellus entered South America and experienced speciation. The same process of re-ingression has been proposed to other xenarthrans, breaking with the traditional assumption that the GABI was unidirectional. 相似文献
154.
Hannah K. Larson Shana K. Goffredi Erica L. Parra Orlando Vargas Adrián A. Pinto-Tomas Terrence P. McGlynn 《Die Naturwissenschaften》2014,101(5):397-406
We document a facultative Bartonella-like Rhizobiales bacterium in the giant tropical ant, Paraponera clavata. In a lowland tropical rainforest in Costa Rica, 59 colonies were assayed for the prevalence of the Bartonella-like bacterium (BLB), 14 of which were positive. We addressed three questions: First, how does the prevalence of BLB within colonies vary with environmental conditions? Second, how does diet affect the prevalence of BLB in P. clavata? Third, how does the distribution of BLB among colonies reflect ambient differences in food resources and foraging habits? A variety of environmental variables that may be predictive of the presence of BLB were measured, and diet manipulations were conducted to test whether the prevalence of BLB responded to supplemental carbohydrate or prey. The ambient frequency of BLB is much higher in young secondary forests, but is nearly absent from older secondary forests. The prevalence of BLB inside field colonies increased over the duration of a 2-week carbohydrate supplementation; however, water and prey supplementation did not alter the prevalence of BLB. The diets of the colonies located in young secondary forest, compared to other habitats, have a diet richer in carbohydrates and lower in prey. The abundance of carbohydrate, or the relative lack of N, in a colony’s diet influences the occurrence of the BLB microbe in P. clavata. As experimental diet manipulations can affect the facultative presence of an N-cycling microbe, a consistent diet shift in diet may facilitate the emergence of tighter symbioses. 相似文献
155.
Samira Veiga Ravaiano Ríudo de Paiva Ferreira Lucio Antonio de Oliveira Campos Gustavo Ferreira Martins 《Die Naturwissenschaften》2014,101(8):603-611
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
156.
157.
Katarzyna?Wojczulanis-JakubasEmail authorView authors OrcID profile Ma?gorzata?E.?Chrostek Frédéric?Jiguet Carlos?Zumalacárregui?Martínez David?Miguélez Júlio?M.?Neto 《Die Naturwissenschaften》2017,104(11-12):101
Differential migration has been extensively reported in spring, but less so in autumn, particularly in relation to sex in monomorphic bird species. Here, we analysed the autumn passage of a monomorphic, globally threatened passerine, the Aquatic Warbler Acrocephalus paludicola throughout Western Europe, with regard to age and sex. We showed that, overall, adults migrated earlier than first-year birds, and males migrated earlier than females during the autumn migration. This may be caused by an overall social dominance of adults over immatures, and differentiated migration strategy of males and females. In addition, we found male-skewed sex proportions, with a tendency to an equalised ratio in more southern stopover sites. This may indicate a male bias in the global population or different migration strategies of the sexes. Differential migration may cause the age and sex classes to be exposed differently to various threats affecting demographic structure of the species. 相似文献
158.
Cristina E. Almeida-Naranjo Bryan Morillo María B. Aldás Nicole Garcés Alexis Debut Victor H. Guerrero 《补救:环境净化治理成本、技术与工艺杂志》2023,33(2):135-150
The removal of heavy metals from wastewater has become a global challenge, which demands the continuous study of efficient and low-cost treatment alternatives such as adsorption. In this research, the removal of zinc was evaluated using batch adsorption processes with nonconventional materials such as graphene oxide (GO), magnetite (MG), and their composites (GO:MG), formulated with three weight ratios (2:1, 1:1, and 1:2). Graphene was synthesized by the modified Marcano method, using pencil lead graphite as a precursor. MG and the composites were synthesized by chemical coprecipitation of ferrous sulfate and ferric chloride. The materials were characterized by Raman and Fourier transform infrared spectroscopies, scanning electron microscopy, X-ray diffraction, and the Brunauer–Emmett–Teller method to determine the functional groups, microstructural and morphological characteristics, and specific surface area. Batch adsorption tests were carried out to optimize the adsorbent dose and contact time with zinc solutions of 10 ppm. Zinc adsorption reached equilibrium at 2 h, with an optimal dose between 0.25 and 1.0 g/L. The maximum zinc removal efficiencies/adsorption capacities were 98.6%/165.6, 83.4%/47.6, 83.5%/21.9, 72.8%/19.9, and 82.2%/9.25 mg/g using GO, 2GO:1MG, 1GO:1MG, 1GO:2MG, and MG, respectively. Furthermore, the analysis of the isotherm and adsorption kinetics models determined that the adsorption processes using MG and the composites fit the Sips and pseudo-second-order models. 相似文献
159.
Junga Petr Trávníček Petr Suchý Pavel Kotek Luboš Vítěz Tomáš 《Journal of Material Cycles and Waste Management》2023,25(1):288-301
Journal of Material Cycles and Waste Management - This work focuses on the issue of emergency prevention in the operation of municipal solid waste landfills. In this work, an emergency is... 相似文献
160.
Canhada João C. S. Paiva Fábio F. G. Shinohara Gabriel M. M. Okimoto Fernando Hiranobe Carlos T. Teixeira Silvio R. Job Aldo E. Santos Renivaldo J. 《Journal of Material Cycles and Waste Management》2023,25(2):944-953
Journal of Material Cycles and Waste Management - Leather production is a technology that boosts the economy because of its versatility and durability. However, the wastes generated throughout the... 相似文献