Bovine herpesvirus 4 immediate early 2 (Rta) gene is an essential gene and is duplicated in bovine herpesvirus 4 isolate U     

Franceschi V  Capocefalo A  Ravanetti L  Vanderplasschen A  Gillet L  Cavirani S  van Santen VL  Donofrio G 《Veterinary microbiology》2011,148(2-4):219-231

The ORF50/Rta gene has been shown to be an essential gene for many gammaherpesviruses. Although the BoHV-4 ORF50/Rta homolog, immediate early gene 2 (IE2), has been shown to activate several BoHV-4 early and late promoters in cotransfection assays, there is no direct proof of its indispensability for progression of the virus to the lytic replication cycle in the context of the viral genome. In the present communication, replication defective BoHV-4-V.test IE2 mutants were efficiently rescued, with respect to production of infectious virus and DNA replication, upon the expression of BoHV-4 ORF50/Rta in trans. Surprisingly, in the course of our studies, we discovered that the IE2 gene is duplicated in the genome of BoHV-4-U.  相似文献   

Invasive potential of biofilm-forming Staphylococci bovine subclinical mastitis isolates     

Manuela Oliveira  Ricardo Bexiga  Sandro Filipe Nunes  Cristina Lobo Vilela 《Journal of veterinary science (Suw?n-si, Korea)》2011,12(1):95-97

Staphylococcus (S.) aureus is a common infectious agent of bovine chronic mastitis, a disease that is difficult to eradicate. The abilities of Staphylococci to be internalized and form a biofilm can contribute to host immunological defence evasion that subsequently impairs antimicrobial therapy. The invasive capability of six S. aureus field isolates with different biofilm-forming profiles was compared in vitro using a bovine mammary epithelial cell line. This was further confirmed in primary cell cultures using fluorescent rRNA probes against S. aureus. The results suggest that S. aureus invasion levels are not related to biofilm formation.  相似文献   

The native South American crayfishes (Crustacea,Parastacidae): state of knowledge and conservation status          下载免费PDF全文

Mauricio Pereira Almerão  Erich Rudolph  Catherine Souty‐Grosset  Keith Crandall  Ludwig Buckup  Julien Amouret  Ana Verdi  Sandro Santos  Paula Beatriz De Araujo 《水产资源保护:海洋与淡水生态系统》2015,25(2):288-301

Water Remediation by Adsorption of Phenol onto Hydrophobic Modified Clay     

Sandro Froehner  Raquel Fernandes Martins  Willian Furukawa  Marcelo Risso Errera 《Water, air, and soil pollution》2009,199(1-4):107-113

In this work we studied the phenol sorption from contaminated water onto modified clay mineral vermiculite and bentonite by insertion of hexadecyltrimethylammonium in the interlayer of clays. The non modified clays showed negligible interaction with phenol. The experimental data were treated using the Freunlich equation which had a good fit. The removal percentages were higher than 35% for modified vermiculite and for modified bentonite, 30%. Vermiculite and bentonite were compared for the removal of phenol from an aqueous solution based on the maximum adsorption capacity of each adsorbent, and no significant difference was found. The adsorption mechanism for both is the same, according to the results. Although, there is a lack of studies using vermiculite for this purpose, it can be concluded that hydrophobic modified vermiculite is very effective for removing phenol from water. Hydrophobic modified bentonite also remove phenol, but in lower proportions.  相似文献   

Alternatives to regular urea for abating N losses in lettuce production under sub-tropical climate     

Rafael?R.?Cantú  Celso?AitaEmail author  Alexandre?Doneda  Diego?A.?Giacomini  Alexandre?Dessbesell  Marlon?Arenhardt  Géssica?G.?De Bastiani  Stefen?B.?Pujol  Philippe?Rochette  Martin?H.?Chantigny  Sandro?J.?Giacomini 《Biology and Fertility of Soils》2017,53(6):589-599

Alternative fertilization practices are needed for reducing gaseous and leaching N losses at high urea application rates. The objective of this study was to compare gaseous N emissions (N₂O and NH₃) and NO₃ ^? concentrations in the soil solution during two successive lettuce cropping seasons under contrasting fertilization practices. Treatments were fertilization with regular urea (U), urea treated with urease [N-(n-butyl) thiophosphoric triamide (NBPT)] and nitrification [dicyandiamide (DCD)] inhibitors (UIs), non-acidified pig slurry compost (PSC), acidified pig slurry compost (APSC), and an unfertilized control (C). Acidification of pig slurry during composting had no impact on soil cumulative N₂O emissions during the cropping seasons. The use of composts resulted in emission factors (EFs) (PSC, 0.09% of applied N; APSC, 0.16%) an order of magnitude smaller than with regular urea (1.63%). Similarly, adding NBPT and DCD to urea reduced the N₂O EF from 1.63 to 0.37% of applied N and fertilizer-induced NH₃ emissions from 30.2 to 3.4% of applied N. Composts and UI resulted in yield-scaled N₂O emissions that were 33 to 49% lower than the unfertilized control and 64 to 73% lower than the regular urea estimates, indicating a greater efficiency of supplied N with composts and UI. Nitrate concentration of the soil solution (at 0.1 and 0.3 m) in PSC, APSC, and UI plots was similar to the control and up to 17 times lower than with regular urea, indicating reduced risks for leaching losses. We conclude that, as compared to regular urea, the use of composted pig slurry, with and without acidification, and the addition of NBPT and DCD inhibitors to urea are good practices to reduce environmental N losses from lettuce production under sub-tropical climate.  相似文献   

Detection of Mycobacterium avium subsp. paratuberculosis in bovine fecal samples: comparison of three polymerase chain reaction-based diagnostic tests with a conventional culture method.     

Simone Taddei  Chiara Robbi  Camilla Cesena  Ilenia Rossi  Emiliana Schiano  Norma Arrigoni  Gaddo Vicenzoni  Sandro Cavirani 《Journal of veterinary diagnostic investigation》2004,16(6):503-508

Three commercially available assays, designed to specifically detect the presence of Mycobacterium avium subsp. paratuberculosis (MAP) in fecal samples by IS900-PCR, were compared with a conventional culture method. Fecal samples from 100 dairy cows were tested. Fifty-four (67.5%) of 80 culture-positive samples were positive for an assay that detects MAP DNA by dot spot hybridization of polymerase chain reaction products (kit A), 48 (60%) were positive by an assay using ethidium bromide staining for agar gel visualization of amplification products (kit B), and 49 (61.3%) were positive by an assay in which amplified products are detected by a colorimetric detection system (kit C). Relative sensitivity of all tests increased in proportion to the presence of MAP in fecal samples. Specificity was 100% based on results from 20 culture-negative samples from an MAP-free herd.  相似文献   

Satellite estimate of grass biomass in a mountainous range in central Italy   总被引：1，自引：0，他引：1  

Gabriele Schino  Flavio Borfecchia  Luigi De Cecco  Camilla Dibari  Massimo Iannetta  Sandro Martini  Franco Pedrotti 《Agroforestry Systems》2003,59(2):157-162

One of the main problems in managing ranges used for extensive pastoralism is the difficulty of obtaining reliable estimates of grass biomass over very large areas. Estimates of grass biomass are useful as an indicator of both available forage and risk of soil erosion. Nevertheless, large scale field measurements are expensive and time-consuming. The use of satellite images may provide a complementary means of estimating grass biomass over very large areas at a reasonable cost. The aim of this study was to test the use of Landsat satellite data for estimating grass biomass in a mountainous range in central Italy used primarily for sheep breeding. During each of four ground campaigns carried out over two years, grass was cut and its biomass measured in 60-90 test plots. Four Landsat images taken simultaneously to the ground campaigns were processed to obtain several vegetation indexes calculated for each ground test plot. The vegetation indexes showed significant correlations with measured grass biomass. The Normalized Difference Vegetation Index (NDVI) provided the most accurate estimate of grass biomass. When data for each of the four ground campaigns were analyzed separately, correlations for early summer campaigns were higher than correlations for late summer campaigns, indicating that when the ratio of dry/green biomass increases, satellite estimate becomes less accurate. Overall, our results show that satellite data can provide a useful source of biomass information for the management of large ranges. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

Site quality evaluation by classification tree: an application to cork quality in Sardinia   总被引：1，自引：0，他引：1  

Piermaria?CoronaEmail author  Sandro?Dettori  Maria?Rosaria?Filigheddu  Federico?Maetzke  Roberto?Scotti 《European Journal of Forest Research》2005,124(1):37-46

Cork harvesting and stopper production represent a major forest industry in Sardinia (Italy). The target of the present investigation was to evaluate the classification tree as a tool to discover possible relationships between microsite characteristics and cork quality. Seven main cork oak (Quercus suber) producing areas have been identified in Sardinia, for a total of more than 122,000 ha. Sixty-three sample trees, distributed among different geographical locations and microsite conditions, were selected. A soil profile near each sample tree was described, soil samples were collected and analysed. After debarking, cork quality of each sample tree was graded by an independent panel of experts. Microsites where trees had more than 50% of the extracted cork graded in the best quality class, according to the official quality standard in Italy, were labelled as prime microsites, the others as nonprime microsites. Relationships between a binary dummy variable (0 for nonprime microsites, 1 for prime microsites) and site factors were investigated using classification tree analysis to select the relevant variables and to define the classification scheme. Prime quality microsites for cork production proved to be characterised by elevation, soil phosphorus content and sandiness. Results have been compared with those of the more conventional parametric approach by logistic regression. The work demonstrates the advantages of the classification tree method. The model may be appropriate for classifications at landscape and stand mapping levels, where it is possible to sample a number of microsites and to evaluate distributional characteristics of model output, while its precision is only indicative when estimating the prime quality of single microsites.  相似文献   

Overview of methods and tools for evaluating future woody biomass availability in European countries     

Susana Barreiro  Mart-Jan Schelhaas  Gerald Kändler  Clara Antón-Fernández  Antoine Colin  Jean-Daniel Bontemps  Iciar Alberdi  Sonia Condés  Marius Dumitru  Angel Ferezliev  Christoph Fischer  Patrizia Gasparini  Thomas Gschwantner  Georg Kindermann  Bjarki Kjartansson  Pál Kovácsevics  Milos Kucera  Anders Lundström  Gheorghe Marin  Gintautas Mozgeris  Thomas Nord-Larsen  Tuula Packalen  John Redmond  Sandro Sacchelli  Allan Sims  Arnór Snorrason  Nickola Stoyanov  Esther Thürig  Per-Erik Wikberg 《Annals of Forest Science》2016,73(4):823-837

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Nickel potentiates soybean resistance against infection by Phakopsora pachyrhizi     

Andersom Milech Einhardt  Sandro Ferreira  Caroline Hawerroth  Samuel Vasconcelos Valadares  Fabricio Ávila Rodrigues 《Plant pathology》2020,69(5):849-859

Asian soybean rust (ASR), caused by the fungus Phakopsora pachyrhizi, causes significant yield losses worldwide. Nickel (Ni) plays a key role in the metabolism of some profitable crops, such as soybeans, because it is a constituent of several biomolecules and is required for the catalytic process of several enzymes. This study investigated the effect of foliar Ni treatment on the potentiation of soybean cultivar TMG 135 resistance to P. pachyrhizi infection at the microscopic, biochemical, and molecular levels. The severity of ASR decreased by 35% in plants treated with Ni. The malondialdehyde concentration, an indicator of cellular oxidative damage, was high in the leaves of plants that were not treated with Ni and was linked to ASR severity and the extensive colonization of the palisade and spongy parenchyma cells by fungal hyphae. The lignin concentration, β-1,3-glucanase activity, and expression of the URE gene and the defence-related genes PAL1.1, PAL2.1, CHI1B1, and PR-1A were up-regulated in Ni-treated plants infected with P. pachyrhizi. The information provided by this study shows the great potential of Ni to increase the basal level of soybean resistance to ASR and to complement other control methods within the context of sustainable agriculture.  相似文献