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21.
Landraces (LRs) are crop populations that are locally grown by farmers; they have a strategic role to play in rebuilding healthy
and complex agro-ecosystems, but are at risk of extinction. This paper outlines how some LRs were rescued with the support
of modern techniques such as molecular markers. Cowpea LRs from Umbria, Italy, were initially characterized for morphological,
organoleptic and genetic traits and reintroduced among farmers. These activities led to an expansion of the area under LR
based cowpea cultivation and increased farmers’ income. To encourage further LR cultivation a request for the Protected Designation
of Origin (PDO) status has been promoted. Investigations were carried out to determine if it is possible to certify that the
product actually belongs to the traditional agricultural and cultural context of the cultivation area. The genetic diversity
and phylogenetic relationships among local LRs, other LRs, commercial varieties, and other taxa were investigated with five
AFLP markers. Although genetic diversity is limited, genetic analysis showed that Umbrian cowpea LRs can be distinguished
from commercial varieties, LRs from abroad and other taxa. There is a tight phylogenetic connection among Umbrian LRs. These
data confirmed the available historical and sociological data and were included in the PDO specification. AFLP markers can
be used to monitor the origin of seed lots that are on the market; this protects the rights of both consumers and farmers.
This case study could be a resource for planning activities for the future on-farm conservation of other LRs in different countries. 相似文献
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Decaro N Elia G Martella V Desario C Campolo M Trani LD Tarsitano E Tempesta M Buonavoglia C 《Veterinary microbiology》2005,105(1):19-28
We describe a rapid, sensitive and reproducible real-time PCR assay for detecting and quantifying canine parvovirus type 2 (CPV-2) DNA in the feces of dogs with diarrhea. An exogenous internal control was added to control the assay performance from extraction to amplification. The method was demonstrated to be highly specific and sensitive, allowing a precise CPV-2 DNA quantitation over a range of eight orders of magnitude (from 10(2) to 10(9) copies of standard DNA). The reproducibility of the CPV-2 real-time PCR assay was assessed by calculating the coefficients of variation (CV) intra-assay and inter-assay for samples containing amounts of CPV-2 DNA spanning the whole range of the real-time PCR standard curve. Then, fecal specimens from diarrheic dogs were analyzed by hemagglutination (HA), conventional PCR and real-time amplification. Comparison between these different techniques revealed that real-time PCR is more sensitive than HA and conventional gel-based PCR, allowing to detect low viral titers of CPV-2 in infected dogs. 相似文献
23.
Analysis of the pore-size distribution and fiber saturation point of native and thermally modified wood using differential scanning calorimetry 总被引:1,自引:0,他引:1
Mario Zauer Jens Kretzschmar Livia Großmann Alexander Pfriem André Wagenführ 《Wood Science and Technology》2014,48(1):177-193
The aim of this paper was to investigate pore-size distributions in the nano-diameter range of wood and their alteration due to thermal modification of wood using thermoporosimetry, and to find out what consequences can be derived regarding the biological durability. Thermoporosimetry is a technique that is based on the measurement using differential scanning calorimetry (DSC). The method is based on the fact that frozen water contained within small pores is at elevated pressure and therefore has a depressed melting temperature as a function of the appropriate pore diameter. In addition, the fiber saturation points (FSP) were determined by DSC. The former were performed in an isothermal-step method and the latter using the continuous heating-up method. Native and thermally modified twin samples of Norway spruce (Picea abies (L.) Karst.), Sycamore maple (Acer pseudoplatanus L.) and European ash (Fraxinus excelsior L.) were analyzed. The results clearly show that the pore shares of wood for the measurable diameter range between 4 and 400 nm decrease considerably in all studied wood species due to thermal modification of the wood. Furthermore, thermal modification of wood leads to a decreased FSP for all studied wood species. For evaluation as well as reproducibility of the results of pore-size distribution and FSP, the consideration of sensible heat and specific heat of fusion plays an important role. If this is not done, it can lead to misinterpretations. 相似文献
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Alexandre Silveira José A. Pereira Jr. Cristiano Poleto João L. M. P. de Lima Flávio A. Gonçalves Livia A. Alvarenga Jorge M. P. G. Isidoro 《Journal of Soils and Sediments》2016,16(11):2640-2650
Purpose
This study aims to quantify and characterise sediments accumulated in the street gutters in an urban area of Poços de Caldas, Brazil. The main research questions are: What type of urban areas, e.g. those under construction, produce most sediments and what are the main characteristics of such sediments? What differences, e.g. granulometry, can be found in loose and adhered sediments? What trace metals can be found in the sediments?Materials and methods
Fieldwork was carried out in a residential area of Poços de Caldas, Brazil. Ten samplings were conducted between May and August 2013 to collect sediments from road gutters. The collected sediments were then divided into ‘loose’ and ‘adhered’, depending on whether they were collected in a first, gentle, sweeping with soft bristled brush or in a subsequent sweeping with a stiff bristled brush. Granulometric curves were drawn for both types of sediments. Fine sediment analyses (≤63 μm) were performed on samples from the last five samplings. Two techniques were used to look for trace elements: energy dispersive X-ray fluorescence (EDXRF) and inductively coupled plasma-atomic emission spectrometry (ICP-AES).Results and discussion
Larger amounts of sediments were collected after lower intensity rainfall events. Higher intensity events seemed to wash the sediments away. A correlation was found between areas under construction and sediment mass production. A characteristic range of granulometries (medium sand), found in our study is in accordance with studies by other authors. An important presence of heavy metals (Cr, Cd, Pb, Zn, Ni and Cu) was detected and characterised. As and Sn were also detected even though they are not often mentioned in the literature on urban soil pollutants.Conclusions
Areas under construction were found to produce more sediments than other areas. The trace metals found in highest concentrations were Pb and As. The heavy metal concentration decreases after wet periods, showing that they are carried by runoff. It is expected that this study may serve as an input for establishing diffuse pollution control and mitigation strategies for the accumulation of pollutants in the urban environment.27.
Moreno A Di Trani L Faccini S Vaccari G Nigrelli D Boniotti MB Falcone E Boni A Chiapponi C Sozzi E Cordioli P 《Veterinary microbiology》2011,149(3-4):472-477
Swine influenza monitoring programs have been in place in Italy since the 1990 s and from 2009 testing for the pandemic H1N1/2009 virus (H1N1pdm) was also performed on all the swine samples positive for type A influenza. This paper reports the isolation and genomic characterization of a novel H1N2 swine influenza reassortant strain from pigs in Italy that was derived from the H1N1pdm virus. In May 2010, mild respiratory symptoms were observed in around 10% of the pigs raised on a fattening farm in Italy. Lung homogenate taken from one pig showing respiratory distress was tested for influenza type A and H1N1pdm by two real time RT-PCR assays. Virus isolation was achieved by inoculation of lung homogenate into specific pathogen free chicken embryonated eggs (SPF CEE) and applied onto Caco-2 cells and then the complete genome sequencing and phylogenetic analysis was performed from the CEE isolate. The lung homogenate proved to be positive for both influenza type A (gene M) and H1N1pdm real time RT-PCRs. Virus isolation (A/Sw/It/116114/2010) was obtained from both SPF CEE and Caco-2 cells. Phylogenetic analysis showed that all of the genes of A/Sw/It/116114/2010, with the exception of neuraminidase (NA), belonged to the H1N1pdm cluster. The NA was closely related to two H1N2 double reassortant swine influenza viruses (SIVs), previously isolated in Sweden and Italy. NA sequences for these three strains were clustering with H3N2 SIVs. The emergence of a novel reassortant H1N2 strain derived from H1N1pdm in swine in Italy raises further concerns about whether these viruses will become established in pigs. The new reassortant not only represents a pandemic (zoonotic) threat but also has unknown livestock implications for the European swine industry. 相似文献
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Nicola Gladden Hayley Haining Livia Henderson Francesco Marchesi Libby Graham Michael McDonald Fraser. R. Murdoch Anna Bruguera Sala Jayne Orr Kathryn Ellis 《Irish veterinary journal》2015,69(1):1
Background and case presentation
A three year old, second lactation Holstein dairy cow presented to the Scottish Centre for Production Animal Health and Food Safety, Glasgow University Veterinary School in November 2014 with a history of post-calving vulval/vaginal bleeding nine days prior to presentation, followed by a sudden reduction in milk yield. Subsequent investigations resulted in a diagnosis of immune-mediated haemolytic anaemia secondary to infection with Mycoplasma wenyonii.Conclusion
This report of a novel presentation of Mycoplasma wenyonii in a dairy cow illustrates the need to consider M.wenyonii as a potential differential diagnosis when a cow presents with anaemia and will discuss the potential implications of the condition at herd-level.29.
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Gianluca Bianchini Stefano Cremonini Dario Di Giuseppe Gilmo Vianello Livia Vittori Antisari 《Journal of Soils and Sediments》2014,14(1):230-242