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51.
Falco biarmicus feldeggii is one of the most threatened taxa in Europe. Its global population is estimated at a few hundred pairs unequally scattered in a vast and fragmented area stretching from Sicily to the Caspian Sea. Most recent counts showed that Italy hosts a large part (>25%) of the whole population. Consequently, Italian authorities promoted a national action plan. In this framework, we carried out the first national survey for the Lanner Falcon in Italy (2003-2004). Our study area covered the whole breeding range, i.e., Sicily and the Italian peninsula (n = 2909 cells 10 x 10 km). When possible, we considered also additional information from previous regional investigations (1993-2001). First, we estimated size and distribution of each breeding subpopulation. Then, we tried to identify, at landscape level, the main environmental features linked to the spatial distribution of the nesting sites. We found the Lanner Falcon in 184 cells (6.4% of the total grid map), but we estimated no more than 140-172 pairs (70-80 of which are in Sicily) in the same breeding season. Higher levels of isolation characterize the continental breeding cells whereas in Sicily cells are much more clustered. Altitude is the main factor influencing cell aggregations in Italy; nevertheless, other environmental variables, such as climate, precipitation, and vegetation may be important. Our results show that the conservation measures adopted in Italy are somewhat inadequate given the low number of breeding pairs included in protected areas (23%-28%). Many small and scattered special areas of conservation (SAC) devoted to conserve priority habitats fit the irregular spatial aggregations of Lanner Falcon sites better than several large special protection areas (SPA).  相似文献   
52.
In the last decades much attention has been dedicated to the interpretation of relevant phenomena in the socio-economic field, highlighting the need of general frameworks of reference for the governance of sustainability and often recurring to the Elkington’s triple bottom line and the Etzkowitz’s triple-helix representations as reference models. In front of a massive scientific production that points out criteria and method of the model, the theory could seem less rich of applications and examples, especially in the field of the inquiry defined by sustainability. In this work, our aim is to provide a little contribution to cover this gap by (1) drawing a more general view from the triple bottom line; (2) highlighting a ‘triple-helix’ functioning in the triple bottom line as represented in the triple helix of sustainability; (3) providing an example, very actual and important, and some general reasoning related to the use of the model as a possible reference in the basic understanding of the complexity of governance for sustainability.  相似文献   
53.
In this paper, we analyze the relative importance and mutual behavior of two competing base-load electricity generation options that each are capable of contributing significantly to the abatement of global CO2 emissions: nuclear energy and coal-based power production complemented with CO2 capture and storage (CCS). We also investigate how, in scenarios developed with an integrated assessment model that simulates the economics of a climate-constrained world, the prospects for nuclear energy would change if exogenous limitations on the spread of nuclear technology were relaxed. Using the climate change economics model World Induced Technical Change Hybrid, we find that until 2050 the growth rates of nuclear electricity generation capacity would become comparable to historical rates observed during the 1980s. Given that nuclear energy continues to face serious challenges and contention, we inspect how extensive the improvements of coal-based power equipped with CCS technology would need to be if our economic optimization model is to significantly scale down the construction of new nuclear power plants.  相似文献   
54.
Environmental Science and Pollution Research - Chipboard production is a source of ambient air pollution. We assessed the spatial variability of outdoor pollutants and residential exposure of...  相似文献   
55.
We report our experience of 14 preimplantation genetic diagnosis (PGD) cycles in eight couples carrying five different single gene disorders, during the last 18 months. Diagnoses were performed for myotonic dystrophy (DM), cystic fibrosis (CF) [ΔF508 and exon 4 (621+1 G>T)], fragile X and CF simultaneously, and two disorders for which PGD had not been previously attempted, namely neurofibromatosis type 2 (NF2) and Crouzon syndrome. Diagnoses for single gene disorders were carried out on ideally two blastomeres biopsied from Day 3 embryos. A highly polymorphic marker was included in each diagnosis to control against contamination. For the dominant disorders, where possible, linked polymorphisms provided an additional means of determining the genotype of the embryo hence reducing the risk of misdiagnosis due to allele dropout (ADO). Multiplex fluorescent polymerase chain reaction (F-PCR) was used in all cases, followed by fragment analysis and/or single-stranded conformation polymorphism (SSCP) for genotyping. Embryo transfer was performed in 13 cycles resulting in one biochemical pregnancy for CF, three normal deliveries (a twin and a singleton) and one early miscarriage for DM and a singleton for Crouzon syndrome. In each case the untransferred embryos were used to confirm the diagnoses performed on the biopsied cells. The results were concordant in all cases. The inclusion of a polymorphic marker allowed the detection of extraneous DNA contamination in two cells from one case. Knowing the genotype of the contaminating DNA allowed its origin to be traced. All five pregnancies were obtained from embryos in which two blastomeres were biopsied for the diagnosis. Our data demonstrate the successful strategy of using multiplex PCR to simultaneously amplify the mutation site and a polymorphic locus, fluorescent PCR technology to achieve greater sensitivity, and two-cell biopsy to increase the efficiency and success of diagnoses. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
56.
Endometriosis has been hypothesised to be linked to persistent and toxic organochlorinated chemicals. Dioxins and dioxin-like compounds have in particular been associated with the disease, mainly on the basis of experimental studies. Data in women are conflicting. A case-control study on 80 Italian nulliparous women of reproductive age was carried out to assess whether there is a correlation between the presence of endometriosis and blood levels of polychlorobiphenyls (PCBs), a family of ubiquitary environmental pollutants which comprises congeners with dioxin-like activity. Higher levels of PCBs were found in women with endometriosis. A mean cumulative value of 410 ng g(-1), lipid base, was found in cases versus the value of 250 ng g(-1) observed in the control group (odds ratio for upper tertile 4.0, CI 95% 1.3-13; p = 0.0003). PCB increase involved both dioxin-like (PCBs 105, 118, 156, and 167) and non-dioxin-like congeners (PCBs 101, 138, 153, 170, 180).  相似文献   
57.
This study evaluated genetic and DNA methylation alteration induced by potassium dichromate in Brassica napus L. plants. Amplified fragment length polymorphism (AFLP) and selective amplification of polymorphic loci (SAMPL) tests revealed dose-related increases in sequence alterations in plantlets exposed to 10-200 mg/l potassium dichromate. Individual plantlets exposed to chromium under similar conditions showed different AFLP and SAMPL DNA profiles. These observations suggest random DNA mutation in response to potassium dichromate and argue against preferential sites for mutation. DNA methylation changes in response to chromium treatment were also evaluated. Two complementary approaches were applied: (i) immunolabelling, using a monoclonal antibody against 5-methylcytosine; and (ii) methylation-sensitive amplified polymorphism (MSAP). Immunolabelling showed cytosine-hypermethylation in the Brassica napus L. genome when plants were treated with potassium dichromate. MSAP analysis showed extensive methylation changes in CCGG-sequences, with the net result being genome-wide hypermethylation. These results showed a clear DNA alteration in plants as a response to chromium exposure and the effect was dose-dependent. DNA polymorphism detected by different markers supports the effectiveness of the use of these tools for the investigation of environmental toxicology and for evaluating the concentration of pollutants by DNA analysis in plants.  相似文献   
58.
Reintroduction of wood in rivers for restoration purposes is now recognized in a positive way by scientists. Nevertheless, the perception of wood in riverscapes is strongly affected by the socio-cultural environment. This cultural influence might explain why wood reintroduction is accepted and promoted in some regions of the world but not in others, despite the demonstrated ecological benefits. From an extensive student perception survey, we show that most of the groups from nine countries in the world considered riverscapes with wood to be less aesthetic, more dangerous, and needing more improvement than riverscapes without wood. By contrast, this way of thinking was not observed in Germany, Sweden, and Oregon (USA), where the first instances of wood reintroduction occurred.  相似文献   
59.
Contaminated water are recognized as a potential source of Cryptosporidium oocysts. In Italy studies on the environmentalspread of the parasite are still scarce even if a high frequencyof serological responses could suggest high rates of endemic Cryptosporidium infections. In this investigation theoccurrence of the parasite in water samples from a municipalwastewater treatment plant was monitored with the aim to evaluatepossible correlation between oocysts and bacterial indicators,pathogens and physico-chemical parameters using a multivariateanalysis. Data collected showed high numbers of oocysts, with ahigh percentage of positive samples and a significant correlationwith pH, redox potential and total organic carbon. No correlationwas found between Cryptosporidium concentration and that of the other microrganisms. The results, through a probing statistical analysis, show that none of the selected microrganisms was a reliable predictor of the presence of theparasite.  相似文献   
60.
The authors compare the diagnostic possibilities of fetal transabdominal echocardiography versus transvaginal echocardiography. A larger diagnostic capacity is verified in different gestation ages with transvaginal probe between the 11th and 14th week of gestation. The results are emphasized by colour Doppler.  相似文献   
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