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101.
Understanding soil gas radon spatial variations can allow the constructor of a new house to prevent radon gas flowing from the ground. Indoor radon concentration distribution depends on many parameters and it is difficult to use its spatial variation to assess radon potential. Many scientists use to measure outdoor soil gas radon concentrations to assess the radon potential. Geostatistical methods provide us a valuable tool to study spatial structure of radon concentration and mapping. To explore the structure of soil gas radon concentration within an area in south Italy and choice a kriging algorithm, we compared the prediction performances of four different kriging algorithms: ordinary kriging, lognormal kriging, ordinary multi-Gaussian kriging, and ordinary indicator cokriging. Their results were compared using an independent validation data set. The comparison of predictions was based on three measures of accuracy: (1) the mean absolute error, (2) the mean-squared error of prediction; (3) the mean relative error, and a measure of effectiveness: the goodness-of-prediction estimate. The results obtained in this case study showed that the multi-Gaussian kriging was the most accurate approach among those considered. Comparing radon anomalies with lithology and fault locations, no evidence of a strict correlation between type of outcropping terrain and radon anomalies was found, except in the western sector where there were granitic and gneissic terrain. Moreover, there was a clear correlation between radon anomalies and fault systems.  相似文献   
102.
Summary This study assessed the contribution of an oil seed industry to the organic loadings of an urban atmosphere, so that more realistic strategies can be developed to control such pollution. Emission measurements suggest that fatty acids, aldehydes and solvent related hydrocarbons are emitted in amounts comparable to or even exceeding anthropogenic organics. Technological options for controlling emissions in the context of the local situation with the data presented are discussed.Paolo Battistoni was born in Ancona, Italy in 1951 and received a degree in chemistry in 1974 at Bologna University. He started his activity at Ancona University where he is a permanent professor of waste water treatments. His research interests have centered on monitoring of organics in ambient air and waste streams and method developments in these areas.Gabriele L. Fava was born near Bologna, Italy in 1945 and received his degree in chemistry from the University of Bologna in 1972. He started his research activity at Ancona University where he is a permanent professor of pollution and environmental control. He has spent research terms at the Iowa State University, USA in 1976 and 1979. His main interest is in the environmental behaviour of toxic substances through physicochemical profiles.  相似文献   
103.
This paper clarifies how polymers are dealt with under the Directive 67/548/EEC. Polymers are a particular group of substances under the Directive 67/548/EEC [1] and amendments [2,3] as they are not listed in the European INventory of Existing Commercial chemical Substances (EINECS [4]) which otherwise lists all substances which were on the European Community Market between 1 January 1971 and 18 September 1981, the ‘existing substances’. Instead, in EINECS polymers are registered under their ultimate building blocks. With the 6th amendment to the Directive [2] polymers became notifiable substances if containing 2% or more of new substance(s) (i.e. as a general rule substances not listed in EINECS), and the reporting criteria were used as definition. With the 7th amendment to the Directive [3] an exact definition was introduced and a special test package, given in Directive 93/105/EEC [5], was designed for polymers to take into account their particular properties. Changing the definition of polymers created a group of substances which under the 6th amendment had been defined as polymers, and could no longer be regarded as polymers under the 7th amendment, the No‐Longer‐Polymers.  相似文献   
104.
Ruello ML  Sileno M  Sani D  Fava G 《Chemosphere》2008,70(6):1135-1140
The objective of this study is to provide an insight into the techniques for measuring the lability of heavy metals in solid-phase pool of soils in order to assess the environmental risk arising from pollution. The technique of diffusive gradients in thin films (DGT) and a sequential extraction procedure were used to quantify the labile pools of Cu, Fe, Mn and Ni. These results were compared to metal concentrations in groundwater, measured directly using the in situ piezometers, and to the total concentration of metal in the soils. High concentrations of metal in the directly analysed soil solution compared to DGT measurement were attributed to the presence of colloidal metal. The use of DGT allowed only to calculate leaching parameters of the free ions and labile fractions of the metals. For this reason DGT technique needs preliminary investigation on metal speciation in soil solution before its application as a good tool in the characterization procedure of contaminated sites.  相似文献   
105.
Sperm competition is a well-recognised agent in the evolution of sperm and ejaculate structure, as well as variation in female quality. Models of the evolution of ejaculate expenditure predict that male body condition, female fecundity and the risk and intensity of sperm competition may be the ultimate factors shaping optimal ejaculate size. We investigated sperm allocation in Austropotamobius italicus, a freshwater crayfish exhibiting a coercive mating system and external fertilisation, in relation to male and female traits and copulation behaviour under laboratory conditions. We found that mating males were sensitive to female size and produced larger ejaculates when mating with larger females, which were more fecund in terms of number of eggs produced. We found no evidence for female egg production being sperm-limited, as the number of eggs was not dependent on male sperm expenditure. Copulation duration and number of ejaculations reliably predicted the amount of sperm transferred, and both these behavioural measures positively covaried with female body size. These results indicate that male freshwater crayfish can modulate their sperm expenditure in accordance with cues that indicate female fecundity. In addition, a novel finding that emerged from this study is the decrease in sperm expenditure with male body size, which may either suggest that large, old male crayfish are better able than small males to economise sperm at a given mating to perform multiple matings during a reproductive season, or that they experience senescence of their reproductive performance.  相似文献   
106.
According to the differential investment hypothesis, females paired with attractive mates are expected to invest more in the current reproduction relative to females paired with unattractive males. We experimentally tested this hypothesis in the peafowl (Pavo cristatus) by providing females with males that differed in sexual attractiveness. In agreement with the differential allocation hypothesis, females paired with more ornamented males laid larger eggs, and deposited higher amounts of testosterone into the egg yolk, independently of the sex of the embryo. These results show that the association between paternal phenotype and offspring quality could arise via a differential maternal investment. They also suggest that, if ornamented males do transmit good genes to the progeny, the maternal differential investment can amplify the effect of such good genes on the offspring fitness.  相似文献   
107.
The evolution of multiple sexual traits remains controversial and poorly understood in evolutionary biology. In many bird species, males exhibit complex courtships involving feather ornaments and behavioral display. Multiple traits may convey information on the genetic and phenotypic quality of males. In particular, fixed characters, such as feather ornaments (produced once a year during the annual molt in many bird species) might convey information about past male condition (at the time of trait development); whereas flexible traits such as behavioral displays should be sensitive to present condition. Here we show that both flexible behavioral displays and fixed feather ornaments of peacocks, used by females to choose a mate, honestly reflect health status. Correlative data showed that peacocks with high display rate (the number of behavioral displays per hour) and a large number of tail eyespots had low levels of circulating heterophils, suggesting better health status. Experimental activation of the immune system, through LPS injection, significantly reduced display rate compared to a control group. However, the sensitivity of a male display rate to the immune challenge was dependent on the number of tail eyespots: males with higher number of tail eyespots were better able to cope with the experimental immune challenge, and maintained their display rate at levels closer to the levels performed before the immune activation. These results are consistent with the idea that multiple signaling might enhance information reliability.  相似文献   
108.
Female preference for mates with elaborated ornaments has often been explained on the basis that exaggerated secondary sexual traits might reflect individual quality and females might gather direct and indirect benefits in mating with such males. Sexual signals must however also entail costs to be reliable indicators of male quality. Androgens have been suggested as a physiological link between sexual signals and individual quality for several reasons, including their immunosuppressive effect. In this study, we tested two hypotheses linked to the hormonal basis of sexual signal expression. First, we investigated whether testosterone is correlated with the size of the black feather bib on the throat of male house sparrows (Passer domesticus) - a trait involved in intra- and inter-sexual selection. Second, we tested whether testosterone affects the seasonal exposure of the trait. Observational work conducted in 1998 showed that the testosterone level was positively correlated with badge size both in spring and in the subsequent fall, after molt. In 1999, we experimentally reduced spring testosterone levels using silastic implants filled with cyproterone acetate, an antiandrogen. Male house sparrows implanted with cyproterone acetate showed reduced exposure of the badge, because the white tips of the black feathers of the badge wore off later than in control males implanted with empty silastic tubes. This result suggests that testosterone can be causally involved in the expression of a secondary sexual trait in house sparrows, at least in terms of its seasonal exposure.  相似文献   
109.
Within the initiatives for poliomyelitis eradication by WHO, Italy activated an environmental surveillance (ES) in 2005. ES complements clinical Acute Flaccid Paralysis (AFP) surveillance for possible polio cases, detects poliovirus circulation in environmental sewage, and is used to monitor transmission in communities. In addition to polioviruses, the analyses comprised: (i) the monitoring of the presence of non-polio enteroviruses in sewage samples and (ii) the temporal and geographical distribution of the detected viruses. From 2009 to 2015, 2880 sewage samples were collected from eight cities participating in the surveillance. Overall, 1479 samples resulted positive for enteroviruses. No wild-type polioviruses were found, although four Sabin-like polioviruses were detected. The low degree of mutation found in the genomes of these four isolates suggests that these viruses have had a limited circulation in the population. All non-polio enteroviruses belonged to species B and the most frequent serotype was CV-B5, followed by CV-B4, E-11, E-6, E-7, CV-B3, and CV-B2. Variations in the frequency of different serotypes were also observed in different seasons and/or Italian areas. Environmental surveillance in Italy, as part of the ‘WHO global polio eradication program’, is a powerful tool to augment the polio surveillance and to investigate the silent circulation or the re-emergence of enteroviruses in the population.  相似文献   
110.
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