434 research outputs found
Global market: shellfish imports as a source of reemerging food-borne hepatitis A virus infections in Spain
A total of 16 mollusk imports from South America to Spain, including clam and scallop species, were analyzed for hepatitis A virus (HAV), due to the great concern about this type of food after an important hepatitis A outbreak in eastern Spain in September 1999. In addition, clams from the stock that had caused the outbreak were also tested. Of the 17 stocks, four were positive for the presence of HAV RNA as demonstrated by RT-PCR and Southern hybridization. Contradictory analyses confirmed the results of the primary tests in all cases. The findings obtained in this work strongly support the role of mollusk imports from endemic areas of HAV as an important vehicle of hepatitis A, and demonstrate the imperative need for sanitary control measures to prevent future outbreaks of this disease
Periodically modulated geometric and electronic structure of graphene on Ru(0001)
We report here on a method to fabricate and characterize highly perfect,
periodically rippled graphene monolayers and islands, epitaxially grown on
single crystal metallic substrates under controlled UHV conditions. The
periodicity of the ripples is dictated by the difference in lattice parameters
of graphene and substrate, and, thus, it is adjustable. We characterize its
perfection at the atomic scale by means of STM and determine its electronic
structure in the real space by local tunnelling spectroscopy. There are
periodic variations in the geometric and electronic structure of the graphene
monolayer. We observe inhomogeneities in the charge distribution, i.e a larger
occupied Density Of States at the higher parts of the ripples. Periodically
rippled graphene might represent the physical realization of an ordered array
of coupled graphene quantum dots. The data show, however, that for rippled
graphene on Ru(0001) both the low and the high parts of the ripples are
metallic. The fabrication of periodically rippled graphene layers with
controllable characteristic length and different bonding interactions with the
substrate will allow a systematic experimental test of this fundamental
problem.Comment: 12 pages. Contribution to the topical issue on graphene of
Semiconductor Science and Technolog
Stability conditions and positivity of invariants of fibrations
We study three methods that prove the positivity of a natural numerical
invariant associated to parameter families of polarized varieties. All
these methods involve different stability conditions. In dimension 2 we prove
that there is a natural connection between them, related to a yet another
stability condition, the linear stability. Finally we make some speculations
and prove new results in higher dimension.Comment: Final version, to appear in the Springer volume dedicated to Klaus
Hulek on the occasion of his 60-th birthda
Draft Genome Sequence of the Emerging Bivalve Pathogen \u3cem\u3eVibrio tubiashii\u3c/em\u3e subsp. \u3cem\u3eeuropaeus\u3c/em\u3e
Vibrio tubiashii subsp. europaeus is a bivalve pathogen isolated during episodes of mortality affecting larval cultures in different shellfish hatcheries. Here, we announce the draft genome sequence of the type strain PP-638 and describe potential virulence factors, which may provide insight into the mechanism of pathogenicity
Draft Genome Sequence of the New Pathogen for Bivalve Larvae \u3cem\u3eVibrio bivalvicida\u3c/em\u3e
Vibrio bivalvicida is a novel pathogen of bivalve larvae responsible for recent vibriosis outbreaks affecting shellfish hatcheries. Here, we announce the draft genome sequence of V. bivalvicida 605 and describe potential virulence factors
Periodically modulated geometric and electronic structure of graphene on Ru(0001)
We report here on a method to fabricate and characterize highly perfect,
periodically rippled graphene monolayers and islands, epitaxially grown on
single crystal metallic substrates under controlled UHV conditions. The
periodicity of the ripples is dictated by the difference in lattice parameters
of graphene and substrate, and, thus, it is adjustable. We characterize its
perfection at the atomic scale by means of STM and determine its electronic
structure in the real space by local tunnelling spectroscopy. There are
periodic variations in the geometric and electronic structure of the graphene
monolayer. We observe inhomogeneities in the charge distribution, i.e a larger
occupied Density Of States at the higher parts of the ripples. Periodically
rippled graphene might represent the physical realization of an ordered array
of coupled graphene quantum dots. The data show, however, that for rippled
graphene on Ru(0001) both the low and the high parts of the ripples are
metallic. The fabrication of periodically rippled graphene layers with
controllable characteristic length and different bonding interactions with the
substrate will allow a systematic experimental test of this fundamental
problem.Comment: 12 pages. Contribution to the topical issue on graphene of
Semiconductor Science and Technolog
Microflora associated with healthy and diseased turbot (Scophthalmus maximus) from three farms in northwest Spain
14 páginas, 4 tablas, 3 figurasA comparative analysis of the microbiological quality of three turbot (Scophthabnus maximus)
farms (A, B, and C) located in Galicia (northwest Spain) is given. The microbial load and types of
bacteria in the internal organs (liver and kidney) of apparently healthy fish was monitored over a
year, and all the disease problems occurring during this survey were analyzed. The percentage of healthy
turbot in which positive bacterial growth was obtained was relatively high in the three ongrowing
facilities. Farm A exhibited the poorest conditions of fish health with an average of 42% fish infected,
while farm B showed the best microbiological quality with 27% of turbot harbouring bacteria in the
internal organs. In all three farms, a wide range of bacteria was found in healthy turbot with Vibrio
( V. splendidus-V pelagius, Vjisheri-V harveyi and Vibrio spp.) and Pseudomonas spp. being the
predominant groups comprising at least 80% of the total bacterial isolates in each farm.
The highest number of pathological problems (22 ) with the most diverse bacterial flora occurred
in farm A. Vibrio spp. and Pseudomonas spp. were the most prevalent bacteria recovered from diseased
turbot. Haemorrhages in palate and jaws, tail and fins, and ulcerative lesions were the most
frequent external clinical signs of diseased fish recorded in the three farms. However, it was not possible
to associate a particular bacterial species with a specific pathology. Routine use in farm A of
oxolinic acid and nitrofurantoin may have led to the development in the Vibrio strains of resistances
to both chemotherapeutants (up to 25%).This study was supported by Grants MAR 9 l- 1133~CO2-0 1 and MAR 89-
0270 from the Comision Interministerial de Ciencia y Tecnologia (CICYT),
XUGA 8030389 from Xunta de Galicia (Spain), and EUREKA project No.
EU-347, between Spain and Norway.Peer reviewe
Hypoacusia in a Patient Treated by Isotretinoin
Isotretinoin is the most effective treatment for severe acne, but there are several adverse effects associated with its use, some of them very exceptional (<1/10000). We report one case of hypoacusia and tinnitus in a 15-year-old boy treated with isotretinoin during 6 weeks, who quickly improved after isotretinoin withdrawal. Also, we comment other publications about hearing alterations in patients treated with isotretinoin and other retinoids
Recurrent inflammatory panniculitis with artial lipoatrophy and elevated temperature: A possible new autoinflammatory disorder
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