109 research outputs found
Not all features are created equal: Processing asymmetries between location and object features
Previous research has shown spontaneous location processing when location is not a task relevant feature
and when a target is presented together with distractors. The present study investigates whether such
processing can occur in the absence of distractor inhibition, and whether there is a processing asymmetry
between location and an object feature. The results show that not all features are created equal. Whereas
attending to an object’s color or texture led to the involuntary processing of that object’s location, attending
to an object’s location did not necessarily result in the encoding of its color or texture when these
nonspatial properties were not task relevant. These results add to the body of evidence demonstrating
the special role of location in attentional selection. They also provide a clearer picture of the interactions
among location, object features, and participants’ behavioral goals
Fast determination of voriconazole in oral fluid using microextractionby packed sorbent and HPLC with fluorescence detection
A fast and reliable method for the determination of voriconazole in oral fluid using microextraction by packed sorbent and liquid chromatography with fluorescence detection was developed and validated. MEPS was performed at basic pH with only 50 μL of oral fluid and the extract was injected without an evaporation step. The overall procedure, including extraction and chromatographic analysis, took only 15 min. Voriconazole and internal standard were separated on a Lichrospher RP 8ec column (250 x 4 mm, particle diameter 5 μm) eluted with a mobile phase composed of phosphate pH 2.3 (containing 0.1 % triethylamine) and acetonitrile (64:36, v/v) at a flow rate of 1.4 mL min-1 . Total run time was 11 min, with detection being performed with excitation at 254 and emission at 372 nm. The method was successfully applied to oral fluid samples, with voriconazole concentrations presenting an average of 57.6 % of those measured in paired plasma samples.Colegio de Farmacéuticos de la Provincia de Buenos Aire
Multicenter prevalence study comparing molecular and toxin assays for clostridioides difficile surveillance, Switzerland
Public health authorities in the United States and Europe recommend surveillance for Clostridioides difficile infections among hospitalized patients, but differing diagnostic algorithms can hamper comparisons between institutions and countries. We compared surveillance based on detection of C. difficile by PCR or enzyme immunoassay (EIA) in a nationwide C. difficile prevalence study in Switzerland. We included all routinely collected stool samples from hospitalized patients with diarrhea in 76 hospitals in Switzerland on 2 days, 1 in winter and 1 in summer, in 2015. EIA C. difficile detection rates were 6.4 cases/10,000 patient bed-days in winter and 5.7 cases/10,000 patient bed-days in summer. PCR detection rates were 11.4 cases/10,000 patient bed-days in winter and 7.1 cases/10,000 patient bed-days in summer. We found PCR used alone increased reported C. difficile prevalence rates by <= 80% compared with a 2-stage EIA-based algorithm.Molecular basis of bacterial pathogenesis, virulence factors and antibiotic resistanc
Down-regulation of porin M35 in Moraxella catarrhalis by aminopenicillins and environmental factors and its potential contribution to the mechanism of resistance to aminopenicillins
The outer membrane protein M35 of Moraxella catarrhalis is an antigenically conserved porin. Knocking out M35 significantly increases the MICs of aminopenicillins. The aim of this study was to determine the biological mechanism of this potentially new antimicrobial resistance mechanism of M. catarrhalis and the behaviour of M35 in general stress situations
Gravitomagnetism in teleparallel gravity
The assumption that matter charges and currents could generate fields, which
are called, by analogy with electromagnetism, gravitoeletric and
gravitomagnetic fields, dates from the origins of General Relativity (GR). On
the other hand, the Teleparallel Equivalent of GR (TEGR), as a gauge theory,
seems to be the ideal scenario to define these fields, based on the gauge field
strength components. The purpose of the present work is to investigate the
nature of the gravitational electric and magnetic fields in the context of the
TEGR, where the tetrad formalism behind it seems to be more appropriated to
deal with phenomena related to observers.
As our main results, we have obtained, for the first time, the exact
expressions for the gravito-electromagnetic fields for the Schwarzschild
solution that in the linear approximation become the usual expected ones. To
improve our understanding about these fields, we have also studied the geometry
produced by a spherical rotating shell in slow motion and weak field regime.
Again, the expressions obtained are in complete agreement with those of
electromagnetism.Comment: 25 pages. Submitted to International Journal of Modern Physics D.
Version 2: some new discussions, references adde
Spin-2 fields and helicity
By considering the irreducible representations of the Lorentz group, an
analysis of the different spin-2 waves is presented. In particular, the
question of the helicity is discussed. It is concluded that, although from the
point of view of representation theory there are no compelling reasons to
choose between spin-2 waves with helicity = + - 1 or helicity = + - 2,
consistency arguments of the ensuing field theories favor waves with helicity =
+ - 1.Comment: 10 pages. V2: presentation changes and discussion adde
Caracterização dos produtores e dos sistemas de produção de leite no perímetro irrigado de Petrolina/PE.
RESUMO - Objetivou-se conhecer alguns aspectos sociais, níveis tecnológicos e resultados econômicos de produtores de leite de vaca em propriedades situadas no Perímetro Irrigado Senador Nilo Coelho, localizado no município de Petrolina, estado de Pernambuco. Foram entrevistados 28 produtores no perímetro, no período de abril a setembro do ano de 2007. As famílias dos produtores que residem nos estabelecimentos rurais e na zona urbana somaram 53,6 e 46,4%, respectivamente. As propriedades estudadas foram classificadas em sua maioria como sistemas intensivos a pasto e em confinamento (57,1%) com produção média de 9,3L/vaca/dia. A renda bruta proveniente do leite foi de R 2.477,47. The ratio between lactating cows and the total number of cows and calving interval were respectively 52.1% and 19,1 months. It was observed that most properties worked with natural mating (96,4%) and manual milking (96,4%). In general vaccination is deficient, however 96,4% of farms vaccinated against Food and Month Disease. Information main source from these producers is television. Regarding the feeding management, it was observed a high dependence on external inputs and the average land productivity and the number of milking cows per area were 3722,0L/ha/year and 1,1 cows/ha, respectively. Dairy cattle have a potential to supplement the producers income, but investments are needed to intensify the use of forage resources, to improve milk quality, reproductive management, nutrition and health herd and technical assistance to producers
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