A NEW TYPE OF RE-ENTRANT CANNULA DESIGNED FOR USE IN THE SMALL INTESTINE OF THE PIG

A new type of intestinal re-entrant cannula for the small intestine of pigs is described. It consisted of an intestinal tube joined to a stem bearing a flange and two perspex plugs ("maintenance plug" and "collection plug"). The cannula was inserted in the intestine through the incision on the antimesenteric side of the intestine and no transection of the intestine was required. No outside connection was present and the cannula extended only 1 to 2cm beyond the body. Cannulae were inserted in the duodenum and ileum of 5 pigs and these functioned satisfactorily for up to 3 months.     

Generation of spatially coherent light at extreme ultraviolet wavelengths

We present spatial coherence measurements of extreme ultraviolet (EUV) light generated through the process of high-harmonic up-conversion of a femtosecond laser. With a phase-matched hollow-fiber geometry, the generated beam was found to exhibit essentially full spatial coherence. The coherence of this laser-like EUV source was shown by recording Gabor holograms of small objects. This work demonstrates the capability to perform EUV holography with a tabletop experimental setup. Such an EUV source, with low divergence and high spatial coherence, can be used for experiments involving high-precision metrology, inspection of optical components for EUV lithography, and microscopy and holography with nanometer resolution. Furthermore, the short time duration of the EUV radiation (a few femtoseconds) will enable EUV microscopy and holography to be performed with ultrahigh time resolution.     

Genetic typing of bovine viral diarrhoea virus: most Slovenian isolates are of genotypes 1d and 1f

A selection of 43 bovine viral diarrhoea viruses isolated from mainly persistently infected cattle on 23 Slovenian farms between 1997 and 2001 were characterised genetically. Viral RNA was extracted from infected cell cultures, reverse transcribed and amplified by PCR with primers targeting the 5'-UTR and the N(pro) gene, followed by direct sequencing of purified PCR products obtained for both genomic regions. The N(pro) sequences provided the best genetic resolution, and gave also higher statistical support for phylogenetic classification of the viruses. Thirty-eight of the Slovenian isolates were of genetic subtypes 1d and 1f, four were 1b, and one subtype 1g. No BVDV type 2 viruses were found. This genetic prevalence matched those previously reported for neighbouring countries, as opposed to findings reported for more distant European countries, e.g. France, Spain and the UK. From eight cattle herds several virus isolates were analysed; with one exception all isolates from each herd were of the same genetic group. Extended sequencing of the N(pro) and part of the C gene of virus isolates with identical 5'-UTR sequences allowed differentiation between isolates obtained at different times from one herd.     

Special issue “Deepen knowledge in plant pathology for innovative agroecology”

This study aimed to determine the genetic variability of isolates of rotting of pineapple fruitlet core in Brazil on the states of Paraiba, Pernambuco and Rio Grande do Norte, based on phylogenetic analysis of the RPB2 gene, morphocultural markers and aggressiveness of the isolates. The phylogenetic reconstruction of maximum parsimony and bayesian inference of the isolates were performed. Twenty-seven phylogenetic lineages were characterized with morphocultural markers on potato dextrose agar and synthetic nutrient-poor agar. The aggressiveness of these lineages were characterized in leaves and fruits of pineapple ‘Pérola’ cultivar. The Phylogenetic reconstruction showed close relationship between isolates of this study and phylogenetic lineages of F. guttiforme, F. ananatum and F. oxysporum by analysis of RPB2 gene. Phylogenetic lineages of this study shared significant morphocultural markers similar to those described for this species. Overall, the lineages related with Fusarium oxysporum Species Complex were more aggressive to the fruits of the Fusarium lineages related with Fusarium fujikuroi Species Complex. It is possible that F. ananatum and F. guttiforme or other lineages closely related to these species or F. oxysporum are present in the fields causing pineapple rotting fruitlet core in fruits of pineapple ‘Pérola’ in Brazil. The used markers determined high genetic variability in isolates analyzed in leaves and pineapple fruit ‘Pérola’ in the states of Paraíba, Pernambuco and Rio Grande do Norte of Brazil and the pathogenic lineages analyzed were better adapted to the fruits than to the detached leaves in pineapple ‘Pérola’ analyzed.     

Influence of stage of development in the efficiency of nitrogen fertilization on poplar

Poplar cuttings (Populus x euroamericana) were planted in pots and grown in a greenhouse for four months with drip irrigation. Two nitrogen (N) doses of 60 and 120 kg nitrate (N-NO₃^?) ha^?1 (labeling with ¹⁵N stable isotopes) were applied at one (time I), two (time II) and three months after of the plantation (time III). The aim of this study was to determine the N-fertilizer application method that resulted in optimal N-uptake by a short-rotation of poplar crop during first year of growth. Our data revealed that NUE (N use efficiency) was largest in the last part of the experiment. The larger development of those plants at this stage enabled the improved absorption and assimilation of N. Furthermore, ¹⁵N also revealed that supply of N at three months post-planting generated more biomass and increased the N reserves in the stem; a key factor for ensuring the optimum regrowth during the second year.     

Amorphous Aluminum Hydroxide Control on Sulfate and Phosphate in Sediment-Solution Systems

We experimentally determined the adsorption characteristics of natural, freshly precipitated Al(OH)₃ for SO₄ and PO₄. The fresh Al precipitate occurred in stream sediment of Jachymov Stream (Czech Republic). The Al-rich sediment strongly adsorbed added PO₄ prior to acidification experiment; this sorbed PO₄ was released only after substantial dissolution of the sediment, at pH?<?3.67. Sorption of P by Al(OH)₃ appears to be an important control on dissolved PO₄ concentration in surface waters, unless there is a large excess of PO₄. Acidification of the sediment-solution system caused protonation of the sediment surface, thereby increasing the adsorption capacity for SO₄. Maximum SO₄ adsorption occurred at pH 4.2, below which dissolution of the sediment offset the increasing anion adsorption capacity, and formation of AISO₄ ⁺ inhibited the increasing SO₄ adsorption capacity. This research demonstrates that there are important pH thresholds for anion adsorption in freshwaters below which dissolution of the Al(OH)₃ substrate reduces total capacity for anion adsorption. In freshwaters, with sufficient concentrations of suspended Al(OH)₃, or in Al(OH)₃-rich sediment, PO₄ mobility will be severely restricted. Suspended Al(OH)₃ in acidified surface waters cannot strongly influence SO₄ concentrations because of the considerably higher total SO₄ concentrations compared to the available surface area.     

Alkaline Comet Assay as a Potential Tool in the Assessment of DNA Integrity in Freshwater Zooplankton Affected by Pollutants from Water Treatment Facility

Water, Air, & Soil Pollution - In this pilot study, we evaluated the usefulness of the alkaline comet assay as a biomonitoring tool at the level of plankton communities affected by varying...