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1.
Effects of soil water potential on stem radius changes of Norway spruce (Picea abies (L.) Karst.) The stem radius of 2 mature Norway spruce trees and the soil water potential were continuously measured in situ with dendrometers and tensiometers, respectively. In a period without growth and frost events the stem radius and the soil water potentials correlated closely. A young spruce tree grown under controlled conditions changed its radius in response to the soil water supply likewise. The shrinkage of the stem was reversible, even if the soil was very dry (soil water potential ± ? 1000 hPa). An estimate of the soil water potential seems to be possible even beyond ? 1000 hPa by measurements of stem radius changes. 相似文献
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Mario Chiari Mariagrazia Zanoni Silvia Tagliabue Antonio Lavazza Loris G Alborali 《Acta veterinaria Scandinavica》2013,55(1):42
Background
Salmonella species (spp.) are zoonotic enteric bacteria able to infect humans, livestock and wildlife.However, little is known about the prevalence and the presence of the different serovars in wildlife. Considering the wide distribution of wild boars and the feeding behaviour (omnivorous scavengers), wild boars may be a good indicator for environmental presence of Salmonella spp. The aims of this study were to determine the presence of Salmonella spp. in hunted wild boars and to determine the serotype the isolated strains.Findings
Over three hunting seasons, the intestinal contents of 1,313 boars hunted in northern Italy were sampled and cultured. Salmonella spp. were isolated from 326 boars (24.82%). Thirty different serovars belonging to three different S. enterica spp. were found. Twenty-one serovars of S. enterica subsp. Enterica were found including the human pathogens S. Typhimurium and S. Enteritidis. In addition, nine serovars belonging to S.enterica subsp. diarizonae and S. enterica subsp. houtenae were detected.Conclusions
Considering the widespread occurrence of wild boars in Europe, the epidemiological role of this species in relation to salmonellosis might be relevant and should be further investigated. Wild boars may act as healthy carriers of a wide range of Salmonella serotypes. 相似文献3.
Enrico Giacomini Nicola Ferrari Alessandra Pitozzi Michela Remistani Daniele Giardiello Dominiek Maes Giovanni Loris Alborali 《Veterinary research communications》2016,40(2):81-88
In this study, we investigated the dynamics of Mycoplasma hyopneumoniae infections in 66 pig farms, with different production systems (one-, two-, and three-site systems), and considered different risk factors. Serological assay was used to detect serum antibodies against M. hyopneumoniae and real time polymerase chain reaction (RT–PCR) was performed to detect M. hyopneumoniae DNA in tracheobronchial swabs. Results demonstrated that M. hyopneumoniae infection status was predominantly influenced by the age of the animals and the type of production system. Infection rates were higher in older animals and the prevalence was higher in the one- and two-site systems than in the three-site systems. Dynamics of infection by RT-PCR showed that earlier M. hyopneumoniae infection on one-site farms occurs earlier, while on two- and three-site farms occurs later but spreads faster, suggesting that contact between animals of different age favors the transmission. 相似文献
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Mario Chiari Nicola Ferrari Daniele Giardiello Paolo Lanfranchi Mariagrazia Zanoni Antonio Lavazza Loris G Alborali 《Acta veterinaria Scandinavica》2014,56(1)
Background
Salmonella spp. have been isolated from a wide range of wild animals. Opportunistic wild carnivores such as red foxes (Vulpes vulpes) and badgers (Meles meles) may act as environmental indicators or as potential sources of salmonellosis in humans. The present study characterizes Salmonella spp. isolated from the intestinal contents of hunted or dead red foxes (n = 509) and badgers (n = 17) in northern Italy.Findings
Thirty-one strains of Salmonella belonging to 3 Salmonella enterica subspecies were isolated. Fourteen different serovars of S. enterica subsp. enterica were identified, among which were serovars often associated with human illness.Conclusions
Wild opportunistic predators can influence the probability of infection of both domestic animals and humans through active shedding of the pathogen to the environment. The epidemiological role of wild carnivores in the spread of salmonellosis needs to be further studied. 相似文献6.
Popesco MC Maclaren EJ Hopkins J Dumas L Cox M Meltesen L McGavran L Wyckoff GJ Sikela JM 《Science (New York, N.Y.)》2006,313(5791):1304-1307
Extreme gene duplication is a major source of evolutionary novelty. A genome-wide survey of gene copy number variation among human and great ape lineages revealed that the most striking human lineage-specific amplification was due to an unknown gene, MGC8902, which is predicted to encode multiple copies of a protein domain of unknown function (DUF1220). Sequences encoding these domains are virtually all primate-specific, show signs of positive selection, and are increasingly amplified generally as a function of a species' evolutionary proximity to humans, where the greatest number of copies (212) is found. DUF1220 domains are highly expressed in brain regions associated with higher cognitive function, and in brain show neuron-specific expression preferentially in cell bodies and dendrites. 相似文献
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Mirco Rodeghiero Sergio Tonolli Loris Vescovo Damiano Gianelle Alessandro Cescatti Matteo Sottocornola 《Forest Ecology and Management》2010
The aim of this inventory (acronym: INFOCARB) was to measure the organic carbon stored in the forest ecosystems of the Trento region (Provincia Autonoma di Trento, Northern Italy) in both above- and belowground pools, according to the Kyoto protocol and IPCC requirements. A total of 150 forest sampling points were selected on the entire regional area (6206 km2) with a statistical sampling approach, based on the timber volume as a proxy variable for a stratified sampling. Each sampling point was located with a GPS receiver and a 600 m2 circular plot was delimited around each point. Inside the plots, the biomass of trees, shrubs and herbaceous vegetation was measured, while litter was collected in systematically placed subplots. Topsoil (down to 30 cm depth) was sampled with the excavation method on three systematically located pits, to determine the organic carbon content, the bulk density and the volume occupied by stones and roots. 相似文献
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Sergio Tonolli Michele Dalponte Loris Vescovo Mirco Rodeghiero Lorenzo Bruzzone Damiano Gianelle 《European Journal of Forest Research》2011,130(4):569-577
In this paper, we present a study on the efficiency of multi-return LIDAR (Light Detection Ranging) data in the estimation
of forest stem volume over a multi-layered forest area in the Italian Alps. The goals of this paper are (1) to verify the
usefulness of multi-return LIDAR data compared to single-return data in forest volume estimation and (2) to define the optimal
resolution of a stem volume distribution raster map over the investigated area. To achieve these goals, raw data were segmented
into a net, and different cell dimensions were investigated to maximize the relationship between the LIDAR data and the ground-truth
information. Twenty predicting variables (e.g., mean height, coefficient of variation) have been extracted from multi-return
LIDAR data, and a multiple linear regression analysis has been used for predicting tree stem volume. Experimental results
found that the optimal resolutions of the net square cells were 40 m. The analysis indicated that in a mixed multi-layered
forest, characterized by a complex vertical structure, the correct selection of the map spatial resolution and the inclusion
of the secondary-return data were important factors for improving the effectiveness of the laser scanning approach in forest
inventories. The experimental tests showed that the chosen model is effective for the estimation of stem volume over the analyzed
area, providing good results on all the three considered validation methods. 相似文献
10.
Andrea Camperio Ciani Loris Palentini L. Martinoli M. Mouna 《Biological conservation》2005,121(4):635-641
An eight-year-long census and habitat evaluation of the Macaca sylvanus population was conducted in a 484-km2 area of the central region of the Middle Atlas Mountains in Morocco between June 1994 and October 2002. The authors walked a 93.5-km circuit - divided into 16 transect segments - 30 times with teams of trained research assistant volunteers, collecting data on a total of 2,805 linear km. Previous studies had reported an average density of 44-70 individuals per km2, while data from the present study indicate a progressive population decline, from 25 to 30 individuals per km2, down to a current average density of 7-10 I/km2. The population decline is attributed to the loss of prime habitat, mainly cedar forest, which has significantly decreased from 1994 to 2002, due to the growing impact of overgrazing by mixed flocks of goats and sheep and consequent forest degradation. At present, human-caused habitat deterioration in the Middle Atlas risks further compromising the future of the world’s only remaining large M. sylvanus population. 相似文献