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131.
Integral quantities, wind run, S, and recirculation factor, R, useful for describing air flow, are calculated and combined with CO2 mixing ratios. Meteorological observations were obtained from a RASS sodar and CO2 mixing ratios from a continuous analyzer installed at a rural site in the upper Spanish plateau. The measuring campaign spread
over 3 years and two approaches were followed. The first approach considered integral quantities on a daily basis and two
classifications of air flow, to date scarcely used. The first classification distinguished among stagnation, recirculation,
and ventilation, the second considering synoptic, meso-, and local scales. Moreover, 52.94% of daily values handled in this
paper corresponded to ventilation and 49.70% to synoptic scale. The main goal of this approach is the subsequent link between
the two classifications: the synoptic scale was associated with ventilation, mesoscale with recirculation and local scale
partially with recirculation. CO2 observations were distributed in air flow groups following these classifications and mesoscale processes were satisfactorily
described since noticeable evidence of transport from nearby cities was observed. In the second approach, S and R pairs were used and CO2 mixing ratios were distributed following percent intervals of ventilation, calculated by binning these pairs. The main goal
of the second approach is to consider only three groups of mixing ratios. In the first group, with high ventilation, mixing
ratios were low. With intermediate ventilation, mixing ratios were medium, and with low ventilation mixing ratios were high.
A contrast of 21 ppm between the third and first groups was obtained at the 95th percentile. Finally, the second group provided
a contrast of 3 ppm between north and south directions and also between east and west attributed to transport from nearby
cities. 相似文献
132.
Christine Vanessa Schmidt Sabine Frohschammer Alexandra Schrempf Jürgen Heinze 《Die Naturwissenschaften》2014,101(1):69-72
Mother–son mating (oedipal mating) is practically non-existent in social Hymenoptera, as queens typically avoid inbreeding, mate only early in life and do not mate again after having begun to lay eggs. In the ant genus Cardiocondyla mating occurs among sib in the natal nests. Sex ratios are extremely female-biased and young queens face the risk of remaining without mating partners. Here, we show that virgin queens of Cardiocondyla argyrotricha produce sons from their own unfertilized eggs and later mate with them to produce female offspring from fertilized eggs. Oedipal mating may allow C. argyrotricha queens to found new colonies when no mating partners are available and thus maintains their unusual life history combining monogyny, mating in the nest, and low male production. Our result indicates that a trait that sporadically occurs in solitary haplodiploid animals may evolve also in social Hymenoptera under appropriate ecological and social conditions. 相似文献
133.
Jesus Rodriguez-Manzano Ayalkibet Hundesa Byron Calgua Anna Carratala Carlos Maluquer de Motes Marta Rusiñol Vanessa Moresco Ana Paula Ramos Fernando Martínez-Marca Miquel Calvo Celia Regina Monte Barardi Rosina Girones Sílvia Bofill-Mas 《Food and environmental virology》2014,6(1):31-41
Shellfish complying with European Regulations based on quantification of fecal bacterial indicators (FIB) are introduced into markets; however, information on viruses, more stable than FIB, is not available in the literature. To assess the presence of noroviruses (NoVs) GI and GII and human adenoviruses (HAdV) in domestic and imported mussels and clams (n = 151) their presence was analyzed during winter seasons (2004–2008) in north-west Spanish markets through a routine surveillance system. All samples tested negative for NoV GI and 13 % were positive for NoV GII. The role of HAdV as viral indicator was evaluated in 20 negative and 10 positive NoV GII samples showing an estimated sensitivity and specificity of HAdV to predict the presence of NoV GII of 100 and 74 % (cut-off 0.5). The levels of HAdV and NoVs and the efficiency of decontamination in shellfish depuration plants (SDP) were evaluated analyzing pre- and post-depurated mussels collected in May–June 2010 from three different SDP. There were no statistically significant differences in the prevalence and quantification of HAdV between pre- and post-depurated shellfish and between seawater entering and leaving the depuration systems. Moreover, infectious HAdV were detected in depurated mussels. These results confirm previous studies showing that current controls and depuration treatments limiting the number of FIB do not guarantee the absence of viruses in shellfish. 相似文献
134.
135.
通过收集网络文本分析游客对旅游目的地形象的评价和感受,运用数据挖掘的手段得到游客感知目的地形象的属性与特征,已成为旅游形象研究的重要途径。本研究以携程旅行网(www.ctrip.com)上发表的韶山游记作为样本,使用Rost Content Mining内容挖掘软件得到游客感知的韶山旅游目的地形象的属性特征,运用内容分析法,建立分析类目。在此基础上,分别对建立的四个分析类目进行分析,探索游客对韶山旅游目的地形象的感知,并就游客对韶山旅游目的地形象的感知进行归纳和分析,由此,得出互联网传播的游客对韶山旅游目的地形象感知的结论。 相似文献
136.
Vanessa Montoro TaborianskiAuthor VitaeRacine T.A. PradoAuthor Vitae 《Environmental Impact Assessment Review》2012,33(1):41-47
The construction industry is one of the greatest sources of pollution because of the high level of energy consumption during its life cycle. In addition to using energy while constructing a building, several systems also use power while the building is operating, especially the air-conditioning system. Energy consumption for this system is related, among other issues, to external air temperature and the required internal temperature of the building. The façades are elements which present the highest level of ambient heat transfer from the outside to the inside of tall buildings. Thus, the type of façade has an influence on energy consumption during the building life cycle and, consequently, contributes to buildings' CO2 emissions, because these emissions are directly connected to energy consumption. Therefore, the aim is to help develop a methodology for evaluating CO2 emissions generated during the life cycle of office building façades. The results, based on the parameters used in this study, show that façades using structural glazing and uncolored glass emit the most CO2 throughout their life cycle, followed by brick façades covered with compound aluminum panels or ACM (Aluminum Composite Material), façades using structural glazing and reflective glass and brick façades with plaster coating. On the other hand, the typology of façade that emits less CO2 is brickwork and mortar because its thermal barrier is better than structural glazing façade and materials used to produce this façade are better than brickwork and ACM. Finally, an uncertainty analysis was conducted to verify the accuracy of the results attained. 相似文献
137.
Vanessa L. Bonanno Albrecht I. Schulte-Hostedde 《Behavioral ecology and sociobiology》2009,63(6):835-846
Sperm competition is widespread in mammals and occurs when ejaculates from two or more males compete within the female’s reproductive
tract to fertilize the ova. Enlarged testes are associated with sperm competition because they produce sperm, but the accessory
glands produce fluids and proteins that are also important for fertilization success. Sperm morphology can also have consequences
for fertilization success because of its influence on sperm motility. Red squirrels engage in multiple mating, and thus sperm
competition is likely. Here, we assess levels of multiple paternity in a natural population of red squirrels, test the prediction
that testis size is correlated with size of the accessory glands and sperm morphometry, and test the prediction that ejaculate
investment is condition-dependent. Five of six litters (83%) showed evidence of multiple paternity, indicating that sperm
competition is likely to have occurred. Testis size was correlated with the size of all three accessory glands (prostate,
seminal vesicle, epididymides), and there was a generally positive relationship between the size of the accessory glands and
sperm length. Sperm morphology showed significant variation in size and shape among individual male squirrels. There was no
evidence of condition dependence of testis size or the size of the accessory glands, but sperm midpiece length was negatively
related to body condition. Further work should include determining the fitness consequence of variation in sperm morphometry,
testis size, and accessory gland size, and determining the effects of variation in ejaculate investment on sperm motility. 相似文献
138.
Beyond Biology: toward a More Public Ecology for Conservation 总被引:3,自引:0,他引:3
Abstract: The ultimate purpose of conservation science is to inform and affect conservation policy. Therefore, conservation biologists and all the people who produce, review, and apply conservation research should evaluate the success of their knowledge according to its ability to influence conservation decisions. In addition to possessing conventional "scientific" attributes such as validity, generalizability, and precision, conservation knowledge must also possess qualities that make it effective in the political arena of decision making. "Public ecology" is a philosophy and practice of conservation science that goes beyond biology and beyond the norms of modern science to construct knowledge that is useful for environmental decision making. As post-normal conservation science, public ecology is defined by the following six attributes: evaluative, contextual, multiscalar, integrative, adaptive, and accessible. We discuss the need for a more public ecology and describe the qualites that make it a more powerful ecology. 相似文献
139.
Noble SR Horstwood MS Davy P Pashley V Spiro B Smith S 《Journal of environmental monitoring : JEM》2008,10(7):830-836
Pb isotope compositions of biologically significant PM(10) atmospheric particulates from a busy roadside location in London UK were measured using solution- and laser ablation-mode MC-ICP-MS. The solution-mode data for PM(10) sampled between 1998-2001 document a dramatic shift to increasingly radiogenic compositions as leaded petrol was phased out. LA-MC-ICP-MS isotope analysis, piloted on a subset of the available samples, is shown to be a potential reconnaissance analytical technique. PM(10) particles trapped on quartz filters were liberated from the filter surface, without ablating the filter substrate, using a 266 nm UV laser and a dynamic, large diameter, low-fluence ablation protocol. The Pb isotope evolution noted in the London data set obtained by both analytical protocols is similar to that observed elsewhere in Western Europe following leaded petrol elimination. The data therefore provide important baseline isotope composition information useful for continued UK atmospheric monitoring through the early 21(st) century. 相似文献
140.