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411.
Changes in land-use/land-cover patterns in Italy and their implications for biodiversity conservation 总被引:2,自引:0,他引:2
Land-use/land-cover change is the most important factor in causing biodiversity loss. The Mediterranean region has been affected
by antropic disturbance for thousands of years, and is, nowadays, one of the most significantly altered hotspots in the world.
However, in the last years a significant increase in forest cover has been measured. These new patterns are independent from
planned conservation strategies and appear to have a substantial impact on landscapes and biodiversity. We used three land-use/land-cover
maps (from 1960 to 2000) covering the Italian peninsula to analyze the pattern of land-use/land-cover change. We measured
an increase in forests, especially in mountains, an increase in artificial areas, especially in coastal zones, and a decrease
in pastures. Intensively cultivated areas showed a limited decrease while extensively cultivated ones showed a marked decrease.
In the same period mammal and bird species followed a similar pattern, with forest birds, ungulates and carnivores increasing,
and typically Mediterranean species decreasing. We suggest that our results may provide important information, which could
be useful for conservation planning in the entire Mediterranean hotspot. We suggest that an increasing conservation effort
should be made to protect the Mediterranean-type forests and scrublands, as well as traditional agricultural practices. Moreover,
future conservation efforts should consider the broad socio-political and ecological processes that are most likely to occur
across the whole hotspot, especially along coastal areas, and the network of protected areas should be functionally integrated
in a conservation strategy that includes the human-dominated landscape. 相似文献
412.
Matteo Tesi Vincenzo Miragliotta Lorenza Scala Elisa Aronica Giulia Lazzarini Diana Fanelli Alessandra Rota Francesca Abramo 《Reproduction in domestic animals》2021,56(5):691-702
The canine placenta is an underexamined organ. Placental abnormalities can affect foetus development and may be responsible for a low weight of the infant at birth; however, knowledge on their clinical significance in the canine species is limited. We aimed to describe macroscopic and microscopic findings in the canine placenta and amnion at term in clinically uncomplicated pregnancies and to evaluate their relationship with birth weight of healthy puppies. During natural delivery or C-section, the birth weight of 82 puppies was recorded, 72 placentas and 66 amnions were recovered. The foetal and maternal surfaces of the placental girdle, marginal haematoma and amnion were evaluated. Each gross finding was recorded, morphometrically assessed and sampled for histological diagnosis. Furthermore, specimens of placenta and amnion were collected from representative areas and microscopic deviations from normal structure were evaluated in haematoxylin and eosin sections. Gross examination revealed ‘abnormalities’ in the 75.4% of the collected placentas. Necrosis was the gross change most commonly observed in the placental girdle (72.5%). Congestion (17.4%) and clotted blood/fibrinoid material (2.9%) were also observed. No gross changes of either the marginal haematoma or the amnion were recorded. Histologically, placental girdle showed necrosis (62.3%), mineralization (52.2%), congestion (36.2%) and neutrophilic infiltration (27.5%). Marginal haematoma exhibited mineralization (11.6%) and neutrophils (29%), while necrotic foci were rarely observed (4.3%). In the amnion, the most frequent alteration observed was hypertrophy of the epithelium (35.9%) followed by oedema (31.2%), mineralized foci (28.1%), fibrosis (23.4%), congestion (15.6%) and more rarely neutrophils (12.5%). Puppies’ birth weight was not statistically affected by either gross or histological abnormalities. Our study revealed that macroscopic and microscopic ‘abnormalities’ of the placenta and amnion may be common in uncomplicated pregnancies at term; however, no implications on puppies’ birth weight were observed. Deviations from ‘normal’ morphology of canine foetal adnexa warrant further investigation to assess their clinical implications if present. 相似文献
413.
Hugo Teixeira Silva Paulo Sávio Lopes Júlio Carvalheira Delvan Alves Silva Alessandra Alves Silva Fabyano Fonseca Silva Renata Veroneze Gertrude Thompson Cláudio Napolis Costa 《Reproduction in domestic animals》2021,56(3):391-399
Reproductive efficiency is major determinant of the dairy herd profitability. Thus, reproductive traits have been widely used as selection objectives in the current dairy cattle breeding programs. We aimed to evaluate strategies to model days open (DO), calving interval (CI) and daughter pregnancy rate (DPR) in Brazilian Holstein cattle. These reproductive traits were analysed by the autoregressive (AR) model and compared with classical repeatability (REP) model using 127,280, 173,092 and 127,280 phenotypic records, respectively. The first three calving orders of cows from 1,469 Holstein herds were used here. The AR model reported lower values for Akaike Information Criteria and Mean Square Errors, as well as larger model probabilities, for all evaluated traits. Similarly, larger additive genetic and lower residual variances were estimated from AR model. Heritability and repeatability estimates were similar for both models. Heritabilities for DO, CI and DPR were 0.04, 0.07 and 0.04; and 0.05, 0.06 and 0.04 for AR and REP models, respectively. Individual EBV reliabilities estimated from AR for DO, CI and DPR were, in average, 0.29, 0.30 and 0.29 units higher than those obtained from REP model. Rank correlation between EBVs obtained from AR and REP models considering the top 10 bulls ranged from 0.72 to 0.76; and increased from 0.98 to 0.99 for the top 100 bulls. The percentage of coincidence between selected bulls from both methods increased over the number of bulls included in the top groups. Overall, the results of model-fitting criteria, genetic parameters estimates and EBV predictions were favourable to the AR model, indicating that it may be applied for genetic evaluation of longitudinal reproductive traits in Brazilian Holstein cattle. 相似文献
414.
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416.
Alessandra Marti Alberto Barbiroli Francesco Bonomi Andrea Brutti Stefania Iametti Mauro Marengo Matteo Miriani Maria Ambrogina Pagani 《Cereal Chemistry》2014,91(4):318-320
The ability of high hydrostatic pressure processing to promote changes in both the structural properties of fiber and the interaction of fiber with water were addressed. Both coarse and fine bran from milling of common wheat were considered. Treatment‐induced morphological changes were most pronounced in fine bran, whereas treatment of coarse bran resulted in the largest change in water‐holding capacity. The significance of the process‐induced changes is discussed in terms of their practical relevance in the production of fiber‐enriched foods. 相似文献
417.
Some problems of eel fishing in hypersaline coastal lagoons are examined by an analysis of eel catches in Porto Pino, three connected basins of about 441 ha in southern Sardinia, where the average catch of eels, about 19 Kg/ha/year, is roughly half the total catch and over 65% of the gross economic return from these ponds.The parameters of the eel population dynamics and the exploitation rate were estimated from the number and weight of eels in each of three trade-weight categories, into which the catch is divided each day as requested by the market, and from examination of random samples, from each stratum, for age and sex. In the particular case of Porto Pino ponds, the estimated yield of 12 g per recruit seems to indicate that the stock of eels is under-fished.The catch is not proportional to the intensity of effort, but depends on environmental conditions, such as lunar phase and presence of wind and/or bad weather conditions. The catch could be increased by using a larger number of winged fyke nets, but should not be sought by extending the fishing period, because that might harm the juveniles of other commercially exploitable species. It is suggested that yield optimisation could be achieved by concentrating the maximum effort in the period of silver eel migration (October–February). In the Mediterranean area, these months are characterized both by suitable environmental conditions and by a peak in the demand for the product. 相似文献
418.
Elisa Pellegrini Alessandra Campanella Giacomo Lorenzini Cristina Nali 《Urban Forestry & Urban Greening》2014,13(4):800-805
The wide diffusion of tropospheric ozone is a major environmental problem, in urban area as well as in rural and remote localities. Its increasing man-related levels are connected to severe impacts on human life and welfare, in terms of adverse health effects, damage to manufacts and injury to plants. Biological monitoring is a powerful tool for filling the gap between the causes and the effects of environmental toxins, as bioindication agents assess in an easy-to-detect fashion the effects of pollution on (selected) biota. A project was launched in 2012 to involve some 190 students (ages 11–16) from three schools in Central Italy in biodetection of ozone effects with the hypersensitive plant Nicotiana tabacum Bel-W3. The project also involved teachers and families of the pupils. Results implied the reading of 12,000 biological data (ozone injury on cotyledons) and were fortified by data captured by four automatic analyzers (1300 raw data of hourly means). Biological and chemical data compared favorably and were treated with geostatistical methods; results are exposed in the form of cartographic restitutions. Under the guidance of their teachers, the pupils had several opportunities to practice with many basic and applied study areas and disciplines and were initiated into the scientific method in a simple and absorbing manner. Though primarily an educational exercise, the survey provided sound research elements and the picture of pollution that emerged has increased the knowledge of air quality in the area. Biomonitoring is confirmed to be a powerful tool to involve young people in environmental topics. 相似文献
419.
Analysis of S‐allele genetic diversity in Sicilian almond germplasm comparing different molecular methods
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Sergio Currò Stefano La Malfa Gaetano Distefano Guiyou Long Francesco Sottile Alessandra Gentile 《Plant Breeding》2015,134(6):713-718
Italian almond germplasm is characterized by a wide diversity in several growing areas among which Sicily is one of the most important. Analysis with consensus and specific primers and DNA sequencing was performed to investigate S‐RNase genetic diversity and to elucidate the homology rate within a genetic pool of 27 Italian accessions. Interestingly, some of the self‐compatible cultivars did not show the presence of Sf allele. Amplicons from consensus and allele‐specific PCR primers revealed a high level of variability. Sequencing of all the S‐RNase amplicons derived from consensus primers allowed the identification of two new S‐RNase alleles (S51 and S52). Surprisingly, despite the AA replacement mutation, S51 did not exhibit any change of its S‐RNase function. Additionally, several mutations, with no effect on amino acid composition, were detected in the intron and/or in the ORF of four known alleles (Sg, S10, S31 and S35). Genetic variation, regarding point mutations and only detected by sequencing, was revealed among 11 of 27 tested cultivars. The new sources of variability might have an interest for product traceability. 相似文献
420.
Vittoria Castiglioni Marcella De Maglie Roberta Queliti Alessandra Rustighi Giannino Del Sal Enrico Radaelli 《Journal of toxicologic pathology》2013,26(4):423-427
A nephroblastoma is a tumor arising from metanephric blastema occurring in childhood.
Among laboratory rodents, nephroblastoma has been frequently reported in rats, but it
remains exceedingly rare in mice. The present work describes a nephroblastoma in a young
mouse homozygous for the specific Trp53 R172H point mutation coupled with targeted
deletion of the Pin1 gene. The affected kidney was effaced by a biphasic
tumor with an epithelial component arranged in tubules surrounded by nests of blastemal
cells. Immunohistochemically, the neoplasm was diffusely positive for Wilms’ tumor
antigen. The epithelial component expressed markers of renal tubular differentiation
including wide-spectrum cytokeratin, E-cadherin and folate-binding protein. Furthermore,
the neoplasm exhibited a high proliferative index and diffuse nucleocytoplasmic β-catenin
expression. Based on histological and immunohistochemical features, a diagnosis of
nephroblastoma potentially associated with Trp53 loss and oncogenic
β-catenin activation has been proposed. 相似文献