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Previous studies have suggested that vegetarianism can result in a reduction of vitamin B12 circulating levels. The aim of the present study was to investigate the effects of a 3-month dietary intervention with a lacto-ovo-vegetarian diet (VD) on the levels of circulating vitamin B12 in a group of omnivores. We analysed fifty-four omnivorous subjects who followed a VD as a first dietary intervention within the CARDIVEG (Cardiovascular Prevention with Vegetarian Diet) study, a dietary intervention study. VD resulted in a significant reduction (P<0·001) of 51·2 % of vitamin B12 intake and in a significant reduction (P=0·005) of 6·2 % of the circulating levels of vitamin B12 (–24·5 pg/ml). Changes in vitamin B12 intake were significantly correlated with changes in circulating levels of vitamin B12 (R 0·61, P<0·001). Subgroup analyses showed that reduction in circulating vitamin B12 levels was more evident in participants who were younger, overweight, non-smokers and had hypercholesterolaemia. A logistic regression analysis showed that a reduction in vitamin B12 intake greater than the first quartile of the delta changes obtained in the study population (–28·5 %) conferred a significantly higher risk of experiencing a decrease in circulating vitamin B12 levels (OR 10·1; 95 % CI 1·3, 76·1). In conclusion, a 3-month VD period determined a significant reduction in circulating levels of vitamin B12, being significantly correlated with the reduction in vitamin B12 intake. Although a well-planned VD can provide adequate nutrition across all life stages, special care must be taken to ensure adequate vitamin B12 intake and to help prevent deficiency.
A series of clinopyroxenes along the CaMgSi2O6–CaCoSi2O6 join was synthesized by quenching from melts at 1500°C and subsequent annealing at 1250°C (at 0.0001 GPa). This protocol proved to be the most effective to obtain homogenous, impurity-free and stoichiometric pyroxenes. Electron microprobe analyses in energy dispersive mode were conducted and single-crystal X-ray diffraction data were collected on Ca (CoxMg1-x)Si2O6 pyroxenes with x = 0.2, 0.4, 0.5, 0.6. Effects of cation substitution at the M1 site are described. The experimental findings of this study allow us to extend the comparative analysis of the structural features of pyroxenes with divalent cations at the M1 and M2 sites.
The annual incidence of listeriosis in Italy is lower (0·19–0·27 per 100 000 inhabitants per year) than in Europe (0·34–0·52 per 100 000 inhabitants per year). Since the observed incidence of listeriosis may be biased downward for underdiagnosis or under-reporting, this work aims to estimate the real incidence of listeriosis during a 9-year period in the Lombardy region, Italy. Data on listeriosis cases were collected from national mandatory notification system (MAINF) and Laboratory-based Surveillance System (LabSS). The two sources were cross-matched and capture–recapture method was applied to estimate the number of undetected cases and the real incidence of invasive listeriosis. Five hundred and eighty invasive listeriosis cases were detected by the two sources between 2006 and 2014: 50·2% were identified only via MAINF, 16·7% were recorded only via LabSS, overlaps occurred in 192 cases (33·1%). The mean annual incidence detected only by MAINF was 0·56 per 100 000 inhabitants, which rose to 0·67 per 100 000 considering also the cases detected by LabSS. The capture–recapture method allowed to estimate an incidence of 0·84 per 100 000. The high incidence of listeriosis may be due to improved sensitivity of the surveillance system, but also reflect a real increase, associated with an increased population at risk.
We have recently developed a set of equations of state based on the nuclear energy density functional theory providing a unified description of the different regions constituting the interior of neutron stars and magnetars. The nuclear functionals, which were constructed from generalized Skyrme effective nucleon-nucleon interactions, yield not only an excellent fit to essentially all experimental atomic mass data but were also constrained to reproduce the neutron-matter equation of state as obtained from realistic many-body calculations.
We study the impact of a hadron-quark phase transition on the maximum neutron-star mass. The hadronic part of the equation of state relies on the most up-to-date Skyrme nuclear energy density functionals, fitted to essentially all experimental nuclear mass data and constrained to reproduce the properties of infinite nuclear matter as obtained from microscopic calculations using realistic forces. We show that the softening of the dense matter equation of state due to the phase transition is not necessarily incompatible with the existence of massive neutron stars like PSR J1614–2230.
Manual surveillance for central line-associated bloodstream infections (CLABSIs) by infection prevention practitioners is time-consuming and often limited to intensive care units (ICUs). An automated surveillance system using existing databases with patient-level variables and microbiology data was investigated.
Patients with a positive blood culture in 4 non-ICU wards at Barnes-Jewish Hospital between July 1, 2005, and December 31, 2006, were evaluated. CLABSI determination for these patients was made via 2 sources; a manual chart review and an automated review from electronically available data. Agreement between these 2 sources was used to develop the best-fit electronic algorithm that used a set of rules to identify a CLABSI. Sensitivity, specificity, predictive values, and Pearson's correlation were calculated for the various rule sets, using manual chart review as the reference standard.
During the study period, 391 positive blood cultures from 331 patients were evaluated. Eighty-five (22%) of these were confirmed to be CLABSI by manual chart review. The best-fit model included presence of a catheter, blood culture positive for known pathogen or blood culture with a common skin contaminant confirmed by a second positive culture and the presence of fever, and no positive cultures with the same organism from another sterile site. The best-performing rule set had an overall sensitivity of 95.2%, specificity of 97.5%, positive predictive value of 90%, and negative predictive value of 99.2% compared with intensive manual surveillance.
Although CLABSIs were slightly overpredicted by electronic surveillance compared with manual chart review, the method offers the possibility of performing acceptably good surveillance in areas where resources do not allow for traditional manual surveillance.
A comparative study of the microtribological properties of native oxide covered single crystal silicon and silicon coated with atomic layer deposited (ALD) alumina films is presented. The dry friction and wear behavior were investigated using a novel microelectromechanical system (MEMS) tribotester. The coefficient of friction for alumina coated surfaces and for silicon uncoated surfaces was monitored before and after wear. The friction versus normal load curves of uncoated silicon can be described by a Johnson-Kendall-Roberts model with pressure dependent shear strength while for the alumina coated surfaces, a linear dependence between the friction force and the normal load was found. Both uncoated silicon surfaces and alumina coated surfaces showed a decrease of the friction force with the number of sliding cycles.
In this paper, a clear view on the bulk microstructure of MDMO-PPV:PCBM blends as used in bulk hetero-junction organic solar cells is obtained by means of TEM (Transmission Electron Microscopy). Using TEM, 3-dimensional information is acquired on phase separated regions, formed during casting. Particle statistics illustrate quantitatively that a.o. drying conditions and choice of solvent dramatically influence the blend structure. More information about the lateral blend structure and distribution is obtained in cross-sectional view. Since blend morphology is strongly related to photovoltaic performance, TEM can be a powerful tool for understanding today's photovoltaic performances and screening new sets of materials.
To estimate the contribution of television (TV) food advertising to the prevalence of obesity among 6–11-year-old children in Australia, Great Britain (England and Scotland only), Italy, The Netherlands, Sweden and the United States.
Data from contemporary representative studies on the prevalence of childhood obesity and on TV food advertising exposure in the above countries were entered into a mathematical simulation model. Two different effect estimators were used to calculate the reduction in prevalence of overweight and obesity in the absence of TV food advertising in each country; one based on literature and one based on experts’ estimates.
Six- to eleven-year-old children in six Western countries.
Estimates of the average exposure of children to TV food advertising range from 1·8 min/d in The Netherlands to 11·5 min/d in the United States. Its contribution to the prevalence of childhood obesity is estimated at 16 %–40 % in the United States, 10 %–28 % in Australia and Italy and 4 %–18 % in Great Britain, Sweden and The Netherlands.
The contribution of TV advertising of foods and drinks to the prevalence of childhood obesity differs distinctly by country and is likely to be significant in some countries.
To develop and evaluate computer algorithms with high negative predictive values that augment traditional surveillance for central line–associated bloodstream infection (CLABSI).
Barnes-Jewish Hospital, a 1,250-bed tertiary care academic hospital in Saint Louis, Missouri.
We evaluated all adult patients in intensive care units who had blood samples collected during the period from July 1, 2005, to June 30,2006, that were positive for a recognized pathogen on culture. Each isolate recovered from culture was evaluated using the definitions for nosocomial CLABSI provided by the National Healthcare Safety Network of the Centers for Disease Control and Prevention. Using manual surveillance by infection prevention specialists as the gold standard, we assessed the ability of various combinations of dichotomous rules to determine whether an isolate was associated with a CLABSI. Sensitivity, specificity, and predictive values were calculated.
Infection prevention specialists identified 67 cases of CLABSI associated with 771 isolates recovered from blood samples. The algorithms excluded approximately 40%-62% of the isolates from consideration as possible causes of CLABSI. The simplest algorithm, with 2 dichotomous rules (ie, the collection of blood samples more than 48 hours after admission and the presence of a central venous catheter within 48 hours before collection of blood samples), had the highest negative predictive value (99.4%) and the lowest specificity (44.2%) for CLABSI. Augmentation of this algorithm with rules for common skin contaminants confirmed by another positive blood culture result yielded in a negative predictive value of 99.2% and a specificity of 68.0%.
An automated approach to surveillance for CLABSI that is characterized by a high negative predictive value can accurately identify and exclude positive culture results not representing CLABSI from further manual surveillance.
The recent site testing pointed out the potential of Dome C for Next
Generation Optical Interferometer. KEOPS (Kilo parsec Explorer
Optical Planet Search) is proposed in a context which also
considere the post VLTI perspectives. This
interferometer will be composed of 36 telescopes with a maximal
baseline of 1 km. This instrument will open new horizons: stellar
imaging, circumstellar environment studies, extra solar planet detection, Earth
like planet search. The possibility of observations in double
field mode takes advantage of the large isopistonic angle to give acces to
faint object (see Elhalkouj 2006). It allows active galactic nuclei and cosmological observations.
The achievement of that project implies different steps. The first
one could be MYKERINOS, proposed by LUAN. This prototype
interferometer, composed to 3 telescopes of 40 cm, demonstrate technological feasibility, complete the specific site
characterisation and contribute to validate the scientific program objectives.
IRAN is a method of beam-combination in the
hypertelescope imaging technique recently introduced by
Labeyrie in optical interferometry. We propose to observe the interferometric image in the pupil plane, performing multi-axial pupil plane interferometry. Imaging is performed in a combined pupil-plane where the point-source intensity distribution (PSID) tends towards a
pseudo Airy disc for a sufficiently large number of telescopes. The image is concentrated into the limited support of the output pupil of the individual telescopes, in which the object-image convolution relation is conserved. Specific deconvolution algorithms have been developped for IRAN hypertelescope imagery, based upon Lucy-like iterative techniques. We show that the classical (image plane) and IRAN (pupil plane) hypertelescope imaging techniques are equivalent if one uses optical fibers for beam transportation. An application to the VLT/VIDA concept is presented.
The inclusion of rotation in massive star models improves the agreement between theory and observations on at least
three important points: 1) rotational mixing allows to produce variations of the surface abundances already
during the Main-Sequence phase as is observed. The changes of the surface abundances are more important when, for a given
initial velocity, the initial masses are larger, and/or the metallicities are lower; 2) the observed number
of red supergiants
at the metallicity of the Small Magellanic Cloud (SMC) can be accounted for; 3) the observed variation of the number ratio
of Wolf-Rayet to O-type stars as a function of the metallicity can be reproduced. For all these comparisons
non-rotating models give unsatisfactory fits. Rotating models results also give interesting
insights on questions such as the origin of Be stars, the mechanisms responsible for
the huge mass loss rates undergone by the Luminous Blue Variables, the rotation rates
of pulsars, the progenitors of collapsars
and the sources of primary nitrogen at low metallicity.
Dust forming systems, in which a phase transition between the gas
phase and the solid state takes place, are seriously affected by the
presence of dust, which causes tight, non-linear interactions
between various physical and chemical processes. As a consequence,
the dynamics of, e.g., a stellar atmosphere and the formation of
dust grains are inseparably connected. Chemical conditions, dust
formation, and dust-induced instabilities in such non-linearly
coupled systems as well as some implications regarding stellar
evolution are discussed.
The detailed modelling of thermonuclear
runaways in novae is a great
This paper focuses on issues where the coupling between
the hydrodynamic and the nuclear aspects is critical. The mixing
of heavy elements at the bottom of the accreted envelope is found to be
Other issues related to the modelling of the mixing at the outer parts of
the convective zone and to the details of the early light curve are also
In order to understand the r-process nucleosynthesis, we evaluate the
precision required for mass and β-decay
half-life measurements planned at future radioactive-ion-beam
facilities. To satisfy a simple requirement that we put on nuclear
model predictions, it is concluded that the detectors for the mass
measurements must have a precision of 1σ <
~ 250 keV,
and that the detectors for the half-life measurements
demand a precision of 1σ <
~ 0.15 ms.
The above two specifications are required at the neutron richness of A/Z = 3.0 at the N=82 shell closure and A/Z = 2.9 at the N=50 shell
closure. For the doubly magic nuclide 78Ni,
a precision of 1σ <
~ 300 keV and
~ 5 ms are required, respectively,
for mass and half-life measurements.
This analysis aims at providing a first rough guide for ongoing detector
Rotation and mass loss appear to resolve many problems remaining in the
evolution of massive stars. But, we may wonder whether magnetic fields
are important or not. Some first effects of the magnetic fields created
by the Tayler-Spruit dynamo
for massive stars are shown. As it stands presently,
the theory does not agree well with observations.
Thus, either magnetic fields are of little importance
in massive stars or the dynamo theory needs to be further improved.
Recent progress in modeling type Ia supernovae by means of 3-dimensional
hydrodynamic simulations as well as several of the still open questions are
addressed. Our models are based on the assumption that thermonuclear burning
inside a Chandrasekhar-mass C+O white dwarf is similar to turbulent chemical
combustion and that, thus, thermonuclear supernovae can be modeled by means
of numerical methods which have been developed and tested for laboratory and
technical flames. It is shown that the new models have considerable
predictive power and allow to study observable properties of type Ia
supernovae, such as their light curves and spectra, without adjustable
non-physical parameters, and they make firm predictions for the
nucleosynthesis yields from the explosions. This raises a quest for better
data, covering the spectroscopical and photometric evolution in all wave
bands from very early epochs all the way into the nebular phase. First such
results obtained by the European Supernova Collaboration (ESC) for a sample
of nearby SNe Ia and their implications for constraining the models and
systematic differences between them are also discussed.
Two examples of stellar predictions from models of asymptotic giant branch
stars are presented to illustrate the difficulties associated with
astronuclear studies. The first example is the dredge-up process by which
nuclei synthesized in the stellar interior are brought to the
surface; the second is the production of primary sodium. Those examples
illustrate the need for a good understanding of the details
of model calculations from both a physical and a numerical stand point.
They highlight as well some of the current limitations of AGB model