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Vaccination coverage (VC) against pertussis can increase when management practices and policies at primary care centres (PCCs) are reinforced. From 2011 to 2015, we performed a case–control study to evaluate VC among pertussis patients treated at PCCs in Barcelona, Spain. We recorded pertussis in patients from 8- to 16-year-olds at 52 PCCs. Pertussis cases had laboratory diagnostic and controls were healthy outpatients visiting the same facility for reasons other than cough. DTaP/dTap VC was recorded as either proper vaccination status (five doses recorded) or improper vaccination status (<5 doses recorded). We used a logistic regression model to estimate OR and 95% CI. We included 229 cases and 576 controls. VC was higher in cases (mean 5.01, s.e.: 0.57) than in controls (4.89, s.e.: 0.73). Around 69% of the cases had received DTaP primary immunisation after 2–5 years and 31.4% of cases had the dTap booster immunisation after 7–10 years. The 87% of children 5–9 years were properly vaccinated. We found no protection from becoming ill among properly vaccinated children (OR 1.87; 95% CI 1.22–2.85). The highest VC was observed in patients with confirmed pertussis, which was likely due to a more exhaustive follow-up of the VC in these patients. Being properly vaccinated against pertussis will probably not increase VC.
This work shows the electrochemical study of nickel (Ni) and TiC/Ni composite immersed in synthetic seawater. In order to characterize the corrosion process, polarization curves (PC) were carried out. All electrochemical measures were made under static conditions, room temperature, atmospheric pressure and 24 hours exposure time. An electrochemical cell with a typical three-electrode array was used. Effect of TiC as reinforcement into the Ni matrix was evaluated. According PC results, it is possible to point out that the corrosion rate (CR) of the TiC/Ni composite was higher than Ni corrosion rate. The obtained results indicate that the corrosion process of both materials is of mixed type, that is to say a process of transfer of load influenced by a mechanism of mass transfer. Observations through scanning electron microscopy (SEM) revealed that mechanism of corrosion was cells of differential aeration (difference of concentration of oxygen). The corrosion morphology was localized type (pits and crevice).
Between 2008 and 2010, 27 acoustic tags were applied to various age and reproductive classes of grey whales in Laguna San Ignacio, Mexico, a part of the Biosphere Reserve ‘El Vizcaino’. Besides previously described S1 and S3 calls, two additional calls were identified: the impulsive S8 call and the slightly frequency-modulated S9 call. These two additional S8 and S9 calls are by far the most common grey whale sounds detected on tags, even though contemporary bottom-mounted acoustic recordings also collected from the lagoon in 2008 yielded no S8 or S9 calls. The new S8 and old S3 calls display similar spectral maxima, even though the S3 is a frequency-modulated harmonic call and the S8 is a broadband impulsive call. This spectral analysis provides evidence that these new call types are not artefacts arising from mechanical vibration or flow noise.
In a 1-year survey at a university hospital we found that 20·6% (81/392) of patients with antibiotic associated diarrohea where positive for C. difficile. The most common PCR ribotypes were 012 (14·8%), 027 (12·3%), 046 (12·3%) and 014/020 (9·9). The incidence rate was 2·6 cases of C. difficile infection for every 1000 outpatients.
Magnetic resonance imaging (MRI) studies have shown that brain abnormalities in psychosis might be progressive during the first years of illness. We sought to determine whether first-episode psychosis (FEP) subjects show progressive regional grey matter (GM) changes compared with controls, and whether those changes are associated with diagnosis, illness course or antipsychotic (AP) use.
Thirty-two subjects with first-episode schizophrenia-spectrum disorders (FESZ), 24 patients with first-episode affective psychoses (FEAP) and 34 controls recruited using a population-based design underwent structural MRI scanning at baseline and at a 5-year follow-up. Regional GM volumes were assessed with voxel-based morphometry (VBM). Patients were treated at community settings, and about half of them remained mainly untreated.
No significant progressive changes in GM regional volumes were observed in either the FESZ or FEAP group overall. However, FESZ subjects with a non-remitting course showed GM decrements in the left superior temporal gyrus (STG) and insula relative to remitted FESZ subjects. Non-remitted FEAP subjects exhibited a GM decrease in the dorsolateral prefrontal cortex (DLPFC) bilaterally in comparison to remitted FEAP subjects. Among FESZ subjects, AP use was associated with regional GM decrements in the right insula and increments in the cerebellum.
Our results suggest that the progression of brain abnormalities in FEP subjects is restricted to those with a poor outcome and differs between diagnosis subgroups. AP intake is associated with a different pattern of GM reductions over time.
It has been an increase on the number of concrete structures with corrosion induced damage in Mexico in recent years. It is also well known that cathodic protection (CP) is the only method that stops corrosion in an efficient way. Since the 1990’s Florida and other USA states have been installing in concrete pile substructures, in bridges and piers, a three part hybrid galvanic CP system. This hybrid galvanic CP system includes a thermal sprayed part (located at the aerial zone of the pile), a zinc mesh encapsulated in mortar and inside a glass fiber jacket (located at the change in ties zone), and a submerged zinc bulk anode (in the submerged zone). From a previous investigation performed by the present authors, it has been found that the mortar inside the fiberglass form may decrease the mesh anode activation and thus decrease the CP system efficiency. Therefore, this investigation includes an evaluation of different additions placed in mortar to increase its electrical and ionic conductivity to increase the efficiency of the entire hybrid system. Additions include carbon, zinc and alumina powders, and this investigation presents preliminary experimental results obtained from the tested mortars (i.e. mortar physical characterization: electrical resistivity, ultrasonic pulse velocity, and total void content).
We report experimental measurements on mixing properties in bidimensional rotating drum. Using an image processing device, we follow the trajectories of tracer particles in a monodisperse assembly of beads. Tracer particles with different size ratios exhibit a violent segregation effect: a smaller particle has a tendency to stay in the centre and a larger one will rather dwell on the edges. Furthermore, for a tracer of identical size, we evidence a specific dispersion property where the centre and the edges are competing attractors of the mixing dynamics.
We study the flow under gravity of a granular model system submitted to shear in a rotating cylinder. The system is confined in a vertical 2D geometry which allows visualisation of the bulk and direct measurements of the velocity and density fields. We establish the existence of scaling properties displayed by velocity and density profiles for a large range ofdifferent flow rates.
We report an experimental study of the ascent of a large disc imbedded in a 2D packing ofsmall beads vertically vibrated. Two distinct mechanisms leading to size segregation are observed in situ. At high acceleration, the convection process associated with surface trapping is predominates. At low acceleration, we examine the effect of the size ratio on the dynamics of the segregation which is either intermittent or continuous. This isdue to the successive formation and destruction of arches.
We study granular materials using both event driven (ED) and molecular dynamics (MD) methods. In the MD simulations we implement linear as well as nonlinear forces and also hysteretic interactions. For multiple collisions the two methods show differences: MD calculations lead to weak, whereas ED methods result in rather strong dissipation, as determined through an effective restitution coefficient.
Neurodevelopmental alterations have been described inconsistently in psychosis probably because of lack of standardization among studies. The aim of this study was to conduct the first longitudinal and population-based magnetic resonance imaging (MRI) evaluation of the presence and size of the cavum septum pellucidum (CSP) and adhesio interthalamica (AI) in a large sample of patients with first-episode psychosis (FEP).
FEP patients (n=122) were subdivided into schizophrenia (n=62), mood disorders (n=46) and other psychosis (n=14) groups and compared to 94 healthy next-door neighbour controls. After 13 months, 80 FEP patients and 52 controls underwent a second MRI examination.
We found significant reductions in the AI length in schizophrenia FEP in comparison with the mood disorders and control subgroups (longer length) at the baseline assessment, and no differences in any measure of the CSP. By contrast, there was a diagnosis×time interaction for the CSP length, with a more prominent increase for this measure in the psychosis group. There was an involution of the AI length over time for all groups but no diagnosis×time interaction.
Our findings suggest that the CSP per se may not be linked to the neurobiology of emerging psychotic disorders, although it might be related to the progression of the disease. However, the fact that the AI length was shown to be shorter at the onset of the disorder supports the neurodevelopmental model of schizophrenia and indicates that an alteration in this grey matter junction may be a risk factor for developing psychosis.
The Urban Areas Working Group is part of the International Atomic Energy Agency’s EMRAS II (Environmental Modelling for Radiation Safety) Programme. The goal of this Working Group is to test and improve the capabilities of models used in assessment of radioactive contamination in urban settings, including dispersion and deposition events, short- and long-term contaminant redistribution following deposition events, and potential countermeasures or remediation efforts for reducing human exposures and doses. The Working Group has developed three modeling exercises, which are designed to permit intercomparison of model predictions and, in one case, comparison of model predictions with measurements. This paper describes the scenarios and provides comparisons of initial modeling results. Reasons for similarities and discrepancies among model predictions are discussed in terms of the modeling approaches, models, and parameter values used by different assessors. Preliminary conclusions emphasize the value of explaining individual approaches and the importance of understanding the effects of different assumptions and parameter values on the modeling results.
Both background rotation and small depths are said to enforce the two-dimensionality of flows. In the current paper, we describe a systematic study of the two-dimensionality of a shallow monopolar vortex subjected to background rotation. Using a perturbation analysis of the Navier–Stokes equations for small aspect ratio (with the fluid depth and a typical radial length scale of the vortex), we found nine different regimes in the parameter space where the flow is governed to lowest order by different sets of equations. From the properties of these sets of equations, it was determined that the flow can be considered as quasi-two-dimensional in only five of the nine regimes. The scaling of the velocity components as given by these sets of equations was compared with results from numerical simulations to find the actual boundaries of the different regimes in the parameter space (), where is the Ekman boundary layer thickness and is the equivalent boundary layer thickness for a monopolar vortex without background rotation. Even though background rotation and small depths do promote the two-dimensionality of flows independently, the combination of these two characteristics does not necessarily have that same effect.
The observed junction between α-CuInSe2 and the In-rich compositions in the β-phase domain (e.g. CuIn3Se5) appears to play an important role in the photovoltaic process . There remain, however, inconsistencies and uncertainties about the boundary and structure of this phase. In general the structure of this phase belongs to defect tetrahedral family of structures , which can be described as normal tetrahedral structures with a certain fixed number of unoccupied structure sites. In this work, the local structures of various (Cu2Se)x(In2Se3)1−x semiconductor alloys in the β-phase domain were studied by Extended X-ray Absorption Fine Structure (EXAFS) and the results were compared to those for the α-CuInSe2 phase. The long- range order of these compositions was studied by X-Ray powder Diffraction (XRD) and electron diffraction. It was found the local structures of these compounds are well defined. These compounds, however, could not be well described by any long-range order structure model, especially the selenium position. First-principles band structure calculations were performed to assist in assigning crystal structures to CuInSe2, CuIn3Se5 and CuIn5Se8. The calculations indicated that the local environments of these compounds are well defined. Their long-range order might depend sensitively on growth history and the configurational entropies as suggested by the similar formation energies of several possible crystal structures for CuIn3Se5 and CuIn5Se8.
Hysteresis free and linear piezoelectric behavior of SrBi4Ti4O15 (SrBIT) is very promising for precise sensors/actuators devices. Despite a quite low longitudinal piezoelectric coefficient (around 15 pC/N), its elevated ferroelectric phase transition temperature (540°C) allows its use above 300°C. Electrical conductivity at such temperatures should be kept as low as possible in order to avoid loss of piezoelectric properties or charge drifts. Under reducing conditions, however, the electrical conductivity may change considerably. The electrical conductivity of SrBi4Ti4O15 (SrBIT) has been measured under controlled oxygen partial pressure at elevated temperatures (700-900°C) from 1 atm down to 10−15atm. From 1 atm down to 10−15 atm pO2, above 700°C, the conductivity of SrBIT exhibits a -1/4 slope in log-log scale indicating n-type conductivity and an impurity controlled oxygen vacancy concentration. A conductivity minimum is observed around 0.2 atm for undoped SrBIT at 800°C. Acceptor doping (Mn) raises the minimum and flattens the conductivity curve with slope around -1/10 at 700°C, and -1/6 at 900°C. Ionic conductivity and defect ionization are discussed to account for this. Preliminary results indicate the possibility of a large, pO2 independent, region, down to 10−15atm pO2. The ionic transport number was found to be 0.42 at 800°C for undoped SrBIT and 0.75 for Mn doped SrBIT. The activation energies of undoped (1.35 eV) and Mn doped (1.44 eV) samples are close to each other as expected for a common mechanism
Thin films of the Bi-2212 and T1–2212 compounds were prepared by MOCVD deposition techniques. Resistivity versus temperature and critical current density measurements were used to characterize the electrical properties. An analysis of the data based on a proposed model determined the influence of intragranular weak links. Thin film samples in both systems with near optimum oxygen doping showed a correlation between the slope and magnitude of the resistivity in the normal state. Samples with reduced oxygen content displayed a strong increase in the intragrain boundary resistance, consistent with weak link defects. The results agree with a similar analysis of YBCO samples and support a common mechanism for the development of weak links in cuprates.
AFM techniques were used to interrogate the mechanical properties of weathered polyester copolymer sheets near the exposed surface. Tapping mode tips, as well as a diamond tip mounted on a high spring constant cantilever, were used to scratch overlapping quadrilateral patterns into the polymer. The marred sites were micrographed and the RMS roughness was used as an index of brittleness. Propagation speed and normal force of the test cycle were optimized.