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1.
In Maryland, U.S., an interim framework has recentlybeen developed for using biologically based thresholds, or `biocriteria', to assess the health of nontidal streams statewide at watershed scales. The evaluation of impairment is based on indices of biological integrity from the Maryland Biological Stream Survey (MBSS). We applied logistic regression to quantify how the biotic integrity of streams at a local scale is affected by cumulative effects resulting from catchment land uses, point sources, and nearby transmission line rights-of-way. Indicators for land use were developed from the remote sensing National Land Cover Data and applied at different scales. We determined that the risk of local impairment in nontidal streams rapidly increases with increased urban land use in the catchment area. The average likelihood of failing biocriteria doubled with every 10% points increment in urban land, thus an increase in urban land use from 0 to 20% quadruples the risk of impairment. For the basins evaluated in this study, catchments with more than 40–50% urban land use had greater than 80% probability of failing biocriteria, on average. Inclusion of rights-of-way and point sources in the model did not significantly improve the fit for this data set, most likely because of their low numbers. The overall results indicate that our predictive modeling approach can help pinpoint stream ecosystems experiencing or vulnerable to degradation.  相似文献   
2.

This paper represents the first result of an active collaboration between the University of Sannio and the San Pio Hospital (Benevento, Italy), started in the 2018, that aims to a detailed mineralogical investigation of urinary stones of patients from Campania region. Herein, selected human bladder stones have been deeply characterized for clinical purposes and environmental biomonitoring, focusing on the importance to evaluate the concentration and distribution of undesired trace elements by means of microscopic techniques in the place of conventional wet chemical analyses. A rare bladder stone with a sea-urchin appearance, known as jackstone calculus, were also investigated (along with bladder stones made of uric acid and brushite) by means a comprehensive analytical approach, including Synchrotron X-ray Diffraction and Simultaneous Thermal Analyses. Main clinical assumptions were inferred according to the morpho-constitutional classification of bladder stones and information about patient’s medical history and lifestyle. In most of the analyzed uroliths, undesired trace elements such as copper, cadmium, lead, chromium, mercury and arsenic have been detected and generally attributable to environmental pollution or contaminated food. Simultaneous occurrence of selenium and mercury should denote a methylmercury detoxification process, probably leading to the formation of a very rare HgSe compound known as tiemannite.

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3.
The reproductive cycle of Geodia cydonium in a semi-enclosed Mediterranean bay (Porto Cesareo, SW Apulia) was studied with monthly frequency over a 3-year period. The investigation was carried out by utilizing a technique consisting of tagging ten individuals with a PVC stick and cutting off, by means of a metal cork borer, small samples (cylinders about 5 cm3 in volume) from each of them for histological analysis. Sexual reproductive elements were detected in all individuals, but in the third year some specimens showed reduced reproductive activity or complete infertility. Spermatogenesis occurred in a short period (from June to August) whereas oogenesis lasted longer (from spring to late summer). Spermatic cysts occurred when the frequency of specimens with oocytes reached its maximum values. A relationship between water temperature and the onset of gamete differentiation was observed. G. cydonium is here confirmed oviparous and gonochoric with a sex ratio in favour of the females. However, in contrast with current literature on Porifera—which suggests that only a limited number of sponges, all belonging to the same species are sexually active—the sexual reproduction of this species involves all the examined individuals. This finding can be explained by the methodological approach used in this research, which differs from the traditional way of assessing the sponge reproductive cycle by analysing randomly collected specimens within a population. The study of a series of individuals over time represents a better “model technique” for investigating sponge sexual reproduction and the effect of environmental parameters on gamete differentiation.  相似文献   
4.
Morphological plasticity and ecological aspects of the demosponge Geodia cydonium (Jameson) were studied from seasonal samples collected over 1 year in two semi-enclosed Mediterranean bays of the Southern Italian coast (Marsala lagoon and Porto Cesareo basin). Sponge specimens present two morphs: sessile and non-sessile, both of which showed constant size distribution and density over the studied year. Sessile specimens were larger in size than non-sessile ones. This feature is particularly evident at Porto Cesareo, where these sponges have a more compact skeletal network than at Marsala (evident both in the cortical spicule size and sponge silica content). Sessile specimens adhere to hard rocky substrates (Porto Cesareo) or phanerogam rhizomes (Marsala); non-sessile ones occur on soft bottom areas. Several morphological and structural features of the non-sessile forms differ in the two environments, but the difference in body shape seems to play the most relevant role in enhancing the colonization of incoherent substrates. Indeed, at Marsala, where the large amount of silt and clay determines the occurrence of a markedly reduced anoxic layer just below the surface of the sediment, non-sessile specimens of G. cydonium are fairly spherical and thus able to roll, dragged by slow circular currents. In addition, the usual association with the red alga Rytyphlöea tinctoria, which almost constantly forms a thick and continuous layer around the sponge, allows them to avoid contact with the substrate. The non-sessile specimens from Porto Cesareo inhabit sandy soft bottoms and are flattened. In such an environment, affected by moderate wave turbulence, the flattened shape widens the contact surface between the body and the substrate, thereby reducing the risk of stranding. The evident signs of abrasion, provided by scanning electron microscopy investigations, on both cortical spicules and outermost sponge surface suggest that sponges rub on the bottom. Sediment, epibiontic organisms, and the phanerogam leaves protect this sciaphilous sponge from high solar radiation, allowing the specimens to live in these shallow environments.  相似文献   
5.
Environmental Science and Pollution Research - Carbendazim and thiram are fungicides used in combination to prevent mold destruction of crops. Studies have demonstrated genotoxicity by these...  相似文献   
6.
Human sapoviruses were identified in 15 (12.4 %) of 121 inlet sewage samples collected from wastewater treatment plants in Naples and Palermo, Italy, in 2011. All strains, except one GI.1, were genotyped as GI.2 by sequencing a capsid gene fragment. This is the first detection of sapovirus in wastewaters in Italy.  相似文献   
7.
This study evaluated the presence and seasonal distribution of polio and other enteroviruses in four wastewater treatment plants in three cities in Italy, using different treatment systems. Detection of enteroviruses was carried out by virus isolation in cell cultures after concentration of water samples collected at both inlet and outlet of the treatment plants, following the methods described in the WHO guidelines. Viral serotypes isolated before and after water treatment were compared. Forty-eight non-polio enteroviruses were isolated from 312 samples collected at the inlet of the four wastewater treatment plants, 35 of which were Coxsackievirus type B (72.9 %) and 13 Echovirus (27.1 %). After treatment, 2 CVB3, 1 CVB5, and 1 Echo 6 were isolated. CVB3 and Echo 6 serotypes were also detected in samples collected at the inlet of the TP, in the same month and year. The high rate of detection of infectious enteroviruses in inlet sewage samples (30.1 %) indicates wide diffusion of these viruses in the populations linked to the collectors. The incomplete removal of infectious viruses following sewage treatment highlights possible risks for public health relate to treated waters discharge into the environment.  相似文献   
8.
Vegetable-derived lubricants (VDL) might be more biodegradable than mineral-derived lubricants (MDL) due to the absence of high molecular weight aromatics, but this remains largely untested in tropical conditions. In this laboratory study, the degradation rates of 2-stroke, 4-stroke and hydraulic VDLs were compared with their MDL counterparts in the presence of mangrove and coral reef microbial communities. While MDLs were comprised largely of unresolved saturated and some aromatic hydrocarbons, their VDL counterparts contained, potentially more degradable, fatty acid methyl esters. Degradation of some VDL was observed by day 7, with the 2-stroke VDL markedly consumed by mangrove microorganisms and the hydraulic VDL degraded by both microorganism communities after this short period. All of the VDL groups were significantly more degraded than the comparable MDLs mineral oil lubricants over 14 days in the presence of either mangrove or coral reef microbial communities. In general the mangrove-sourced microorganisms more efficiently degraded the lubricants than reef-sourced microorganisms.  相似文献   
9.
 The variations in both silica content and spicular size were studied in two populations of the demosponge Pellina semitubulosa (Lieberkühn). Samples were collected over a period of 1 year (June 1994 to May 1995) in two Mediterranean coastal basins: Porto Cesareo (southwestern Apulia) and Marsala (northwestern Sicily). The values of spicule size (length and width) and sponge silica content were significantly higher in the population of Porto Cesareo, where the highest water silica concentration was recorded. In both Porto Cesareo and Marsala the sponge silica content showed a seasonal trend, positively correlated with water temperature values. In both populations, the smallest spicules were found in specimens collected from summer to late autumn, after sexual reproduction. Secretion of new spicules may be connected with the process of remodelling occurring in sponges after gamete and larval release. Received: 10 October 1999 / Accepted: 13 April 2000  相似文献   
10.
As regards the incineration process of the urban solid waste, the composition correct management allows not only the valorization of precise civil and industrial groups of waste as alternative fuels but also a considerable increase of the furnace work temperature leading to a remarkable improvement of the related energy efficiency. In this sense, the study of the melting behavior of ashes deriving from several kinds of fuels that have to be processed to heat treatment is really important. This approach, indeed, ensures to know in depth the features defining the melting behavior of these analyzed samples, and as a consequence, gives us the necessary data in order to identify the best mixture of components to be incinerated as a function of the specific working temperatures of the power plant. Firstly, this study aims to find a way to establish the softening and melting temperatures of the ashes because they are those parameters that strongly influence the use of fuels. For this reason, in this work, the fusibility of waste-derived ashes with different composition has been investigated by means of the heating microscope. This instrument is fundamental to prove the strict dependence of the ashes fusion temperature on the heating rate that the samples experienced during the thermal cycle. In addition, in this work, another technological feature of the instrument has been used allowing to set an instantaneous heating directly on the sample in order to accurately reproduce the industrial conditions which characterize the incineration plants. The comparison between the final results shows that, in effect, the achievement of the best performances of the furnace is due to the a priori study of the melting behavior of the single available components.  相似文献   
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