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661.
Behavioral genomics of honeybee foraging and nest defense 总被引:9,自引:1,他引:8
Hunt GJ Amdam GV Schlipalius D Emore C Sardesai N Williams CE Rueppell O Guzmán-Novoa E Arechavaleta-Velasco M Chandra S Fondrk MK Beye M Page RE 《Die Naturwissenschaften》2007,94(4):247-267
The honeybee has been the most important insect species for study of social behavior. The recently released draft genomic
sequence for the bee will accelerate honeybee behavioral genetics. Although we lack sufficient tools to manipulate this genome
easily, quantitative trait loci (QTLs) that influence natural variation in behavior have been identified and tested for their
effects on correlated behavioral traits. We review what is known about the genetics and physiology of two behavioral traits
in honeybees, foraging specialization (pollen versus nectar), and defensive behavior, and present evidence that map-based
cloning of genes is more feasible in the bee than in other metazoans. We also present bioinformatic analyses of candidate
genes within QTL confidence intervals (CIs). The high recombination rate of the bee made it possible to narrow the search
to regions containing only 17–61 predicted peptides for each QTL, although CIs covered large genetic distances. Knowledge
of correlated behavioral traits, comparative bioinformatics, and expression assays facilitated evaluation of candidate genes.
An overrepresentation of genes involved in ovarian development and insulin-like signaling components within pollen foraging
QTL regions suggests that an ancestral reproductive gene network was co-opted during the evolution of foraging specialization.
The major QTL influencing defensive/aggressive behavior contains orthologs of genes involved in central nervous system activity
and neurogenesis. Candidates at the other two defensive-behavior QTLs include modulators of sensory signaling (Am5HT
7
serotonin receptor, AmArr4 arrestin, and GABA-B-R1 receptor). These studies are the first step in linking natural variation in honeybee social behavior
to the identification of underlying genes. 相似文献
662.
663.
José A. Manzanilla-Cano Manuel H. Barceló-Quintal Ligia Del C. Alcocer-Can Tania I. Coral-Martínez 《Journal of environmental science and health. Part. B》2013,48(4):274-278
Photochemical degradation of methylparathion (O,O,–dimethyl O-4 nitrophenylphosphorothioate) in the presence of fulvic acid (FA) between pH 2 and 7 was studied by differential pulse polarography (DPP). Fulvic acid and its photoproducts were not electro-active under the experimental conditions used in this study, and only the pesticide exhibited polarographic signals. Photolysis of methylparathion in acid media was sensitized by fulvic acid since the pesticide did not degrade in the absence of this compound. Methylparathion degradation was observed at each of the studied pHs. The reaction was first-order with rate constant values ranging from 3.3 × 10?3 to 8.8 × 10?3min?1. 相似文献
664.
Mohammad T. Dastorani Alireza Moghadamnia Jamshid Piri Miguel Rico-Ramirez 《Environmental monitoring and assessment》2010,166(1-4):421-434
Hydrological yearbooks, especially in developing countries, are full of gaps in flow data series. Filling missing records is needed to make feasibility studies, potential assessment, and real-time decision making. In this research project, it was tried to predict the missing data of gauging stations using data from neighboring sites and a relevant architecture of artificial neural networks (ANN) as well as adaptive neuro-fuzzy inference system (ANFIS). To be able to evaluate the results produced by these new techniques, two traditionally used methods including the normal ratio method and the correlation method were also employed. According to the results, although in some cases all four methods presented acceptable predictions, the ANFIS technique presented a superior ability to predict missing flow data especially in arid land stations with variable and heterogeneous data. Comparing the results, ANN was also found as an efficient method to predict the missing data in comparison to the traditional approaches. 相似文献
665.
Manuel M. Reglero 《Environmental pollution (Barking, Essex : 1987)》2009,157(4):1388-1395
The Pb mining area of the valley of Alcudia and the Sierra Madrona mountains (S. Spain) has been exploited intermittently for over 2100 years, since Roman occupation and up until the late 1900s. Red deer (n = 168) and wild boar (n = 58) liver and bone (metacarpus) were analyzed for Pb, Zn, Cu, Cd, As and Se. Lipid peroxidation, total and oxidized glutathione (GSH), superoxide dismutase (SOD), GSH peroxidase (GPX) and fatty acid composition were studied in liver of red deer. The concentrations of Pb in liver and bone of red deer and wild boar were higher in the mining area than in the control area, and higher in the wild boar than red deer, but well below the level associated with clinical signs of Pb poisoning. Liver levels of Cu, Cd and Se were also higher in red deer from the mining area. Red deer from the mining area had 39% less total GSH than in the control area. The percentage of docosahexaenoic acid in liver of red deer from the mining area was 16% lower than in the control area. 相似文献
666.
Maria João Rocha Catarina Cruzeiro Mário Reis Eduardo Rocha Miguel Pardal 《Environmental monitoring and assessment》2013,185(10):8215-8226
In spite of its outstanding ecological and touristic importance the Ria Formosa Lagoon shows signs of anthropogenic pollution. Nonetheless, until the present survey no studies had ever documented the measurement of natural and pharmaceutical estrogens (17β-estradiol, estrone, and 17α-ethynylestradiol), xenoestrogenic industrial pollutants (4-octylphenol, 4-nonylphenol, and their mono and diethoxylates and bisphenol A), phytoestrogens (formononetin, biochanin A, daidzein, genistein), and sitosterol in this area. The 17 compounds measured herein are known as endocrine disrupters (EDCs) and act over the endocrine system even in few amounts (ng L?1–μg L?1). Thus to conclude about the influx of EDCs in the lagoon, water samples were taken every 2 months, during 1 year (2010), in low tide at nine sites distributed along the coastline. Water samples (1 L) were preconcentrated in the Oasis HLB cartridges and cleaned in silica cartridges before their analysis by GC-MS. Data showed the ubiquitous presence of potentially hazardous amounts of estrogens (particularly of ethynylestradiol, up to 24.3 ng L?1), nonylphenol (up to 547 ng L?1), and sitosterol (up to 12,300 ng L?1), mainly in summer, suggesting that the increase of the local number of inhabitants (tourists), the rise of the water temperature (up to 26 °C), and the blooming of local flora may interfere with the water quality parameters. This makes the lagoon a potential model to study. Taking into account the data, it was concluded that there are conditions for the occurrence of endocrine disruption in aquatic animals, even in areas included in the natural park of the Formosa. Besides, both the high amounts of un-ionized ammonia (up to 0.3 mg L?1) and phosphates (up to 1.6 mg L?1) my pose risks for local fauna and humans. 相似文献
667.
Laboratory study on the leaching potential of spent alkaline batteries using a MSW landfill leachate
Susana Xará Julanda Delgado Manuel Fonseca Almeida Carlos Costa 《Journal of Material Cycles and Waste Management》2013,15(1):61-72
Two leaching tests were carried out, one with whole batteries and another with cross-cut batteries. In both cases, NEN 7343 (a Nederland’s Standard) procedure was followed using a municipal solid waste (MSW) landfill leachate as extraction solution. Seven fractions were collected corresponding to cumulative liquid/solid (L/S) ratio from 0.1 to 10.0. Those fractions were separately characterized in terms of pH, conductivity, redox potential, density, sulphate, chloride, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Sb, Tl and Zn. Results showed that the influence of the alkaline batteries in the landfill leachate composition varies with their physical integrity and with the L/S ratio, and several variations were observed throughout the tests. The leachate pH and redox potential increased as result of the contact with batteries, particularly pH in the test with the cross-cut batteries. The leachate density and conductivity did not change significantly with the whole batteries, in contrast with the test with cross-cut batteries. 相似文献
668.
Ronaldo Sousa Ângela Amorim Carina Sobral Elsa Froufe Simone Varandas Amílcar Teixeira Manuel Lopes-Lima 《Environmental management》2013,52(5):1230-1238
An important population of the critically endangered pearl mussel Margaritifera margaritifera (Linnaeus, 1758) was surveyed at the edge of its southern distribution (River Paiva, Portugal). Although an earlier study suggested that this population had a very low number of individuals (<500), a narrow distribution, and was mainly comprised by old specimens our data contradict these findings. Our assessment estimated a population with probably more than 5,000 individuals distributed across 80 km of the river length. From the 32 sites surveyed, 19 contained M. margaritifera with higher abundances verified in the middle and upper parts of the river (a maximum of 78 ind. per 100 m of river stretch was recorded). The pearl mussels showed a clear preference for areas near the banks, in shallow water, sandier and gravel sediments, and a high degree of riparian vegetation cover. The population structure was skewed with a very high percentage of large (and old) animals but 3.7 % of the individuals collected were juveniles (<60 mm in length); therefore, this population can be considered functional. Environmental characterization indicated that this river is still in excellent or good condition although some areas showed deterioration due to discharge of domestic effluents. The main conservation requirements of M. margaritifera in the River Paiva include maintaining the water quality (and if possible stopping the discharge of domestic effluents), increasing riparian vegetation cover, removing several weirs to increase connectivity, and increasing trout density. 相似文献
669.
Aitana Sevilla Miguel Luis Rodríguez Ángela García-Maraver Montserrat Zamorano 《Waste management (New York, N.Y.)》2013,33(5):1037-1046
Urban surfaces receive waste deposits from natural and human sources, which create a negative visual impact and are identified as potentially significant contributors to water and air pollution. Local councils are usually responsible for the sweep of roads and footpaths to keep the environment clean and free of litter. Quality controls are useful in order to check whether the services are being executed according to the quantity, quality and performance standards that are provided. In this sense, several factors might affect the efficiency of the management of cleaning and waste collection services; however, only a few contributions are available in the literature on the various aspects associated with the level of street cleanliness. In this paper, the suitability of a Cleanliness Index has been checked, for the case of Granada (South of Spain), in order to contribute to the proper management of public expenditure, improving the quality and cost of an essential service for any municipality. Results have concluded that the city exhibits a good level of cleanliness, although the standard of cleaning varied from one area of the city to another. The Cleaning Index fits well to the general situation of the different districts of Granada and thus, it could be considered a useful tool for measuring the level of cleanliness of the streets of the city and for evaluating the organization of the cleaning service, such that an outsourced company would not be responsible for controlling all the cleaning services. 相似文献
670.
Manuel M. Reglero Mark A. Taggart Pilar Castellanos Rafael Mateo 《Environmental pollution (Barking, Essex : 1987)》2009,157(8-9):2209-2215
We studied the effects of elevated heavy metal uptake on the sperm quality and the antioxidant mechanisms of sperm and testis of red deer from a Pb mining area in Spain. Testis, liver and bone of red deer from mining (n = 21) and control (n = 20) areas were obtained from hunters and analyzed for Pb, Zn, Cu, Cd, As and Se. Testes were weighed and measured. Motility, acrosome integrity and viability and functionality of membrane were evaluated in epididymal spermatozoa. Lipid peroxidation, total glutathione, glutathione peroxidase (GPX) and superoxide dismutase (SOD) were studied in testis and spermatozoa. Deer from mined areas showed less Cu in testis, a higher testis mass and size and reduced spermatozoa membrane viability and acrosome integrity. Effects on sperm quality were associated to decreased Cu and increased Se in testis, and to decreases in the activity of SOD and GPX in testis and spermatozoa. 相似文献