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Tuberculosis (TB) is still a major public health problem in many countries, including Brazil. Primary health care (PHC) services are a set of important services with infrastructure and resources to diagnose, treat, and cure several diseases, including the TB.
The aim of this study is to analyse aspects of the facility infrastructure of Brazilian PHC, regarding the control and treatment of TB from a countrywide perspective.
This is a cross-sectional study based on PHC services. Data were collected from 38,812 health centres and were assessed by means of the National Program for Improving Access and Quality Primary Care. The outcome was obtained by the presence and availability of the following infrastructure items: air circulation in the consultation room, refrigerator, individual protective equipment, plastic jar for sputum examination, and TB notification form of the primary care information system. Poisson regression was used to calculate the prevalence ratio.
Of the 38,812 evaluated centres, only 1628 (4.2%) presented a positive result regarding the outcome. Primary health centres, among all types of centres, presented the highest quality of facility infrastructure for TB control. Centres with large workloads, as well as those that presented a list of offered services and a welcoming consulting room, also presented the highest quality infrastructure. The present study shows that major improvements should be made to the infrastructure to reach a satisfactory TB control in Brazil.
The aim of the present study was to assess the association of gestational diabetes mellitus (GDM) with prenatal and postnatal depressive symptoms in a sample of pregnant women in Greece.
Earlier research supports a relationship between depression and diabetes, but only a few studies have examined the relationship between GDM and perinatal depressive symptomatology.
A total of 117 women in their third trimester of pregnancy participated in the study. Demographic and obstetric history data were recorded during women’s third trimester of pregnancy. Depressive symptoms were assessed with the validated Greek version of the Edinburg Postnatal Depression Scale (EPDS) at two time points: on the third trimester of pregnancy and on the first week postpartum.
Prevalence of GDM was 14.5%. Probable diagnosis of depression occurred for 12% of the sample during the antenatal assessment and 15.1% in the postpartum assessment. In the first week postpartum, women with GDM had significantly higher postpartum (but no antenatal) EPDS scores compared with the non-GDM cohort. In conclusion, GDM appears to be associated with depressive symptoms in the first week postpartum. Clinical implications and recommendations for future research are discussed, emphasizing the importance of closely monitoring women with GDM who seem more vulnerable to developing depressive symptomatology during the postnatal period.
Between 1962 and 1972 the southern hemisphere has been covered by a 4-fold overlap pattern on 5820 plates, taken with a scale of 100 arcsec/mm and using a visual bandpass. More than 2 million pairs of x,y coordinates of the 2 exposures from 276259 stars have been measured at RGO with the GALAXY machine. The conventional plate adjustment, carried out at Hamburg Observatory, is now complete. About 150 000 primary stars will achieve a catalogue accuracy of about 0.06 arcsec at epoch of observation.
The rigorous FK4 and FK5 versions, using the SRS catalogue (C. Smith 1988), will be supplemented by preliminary new proper motions for those stars common with the SAOC. Finally, a rigorous block adjustment will be performed within the next year.
The photodegradation of polypropylene (PP)/ZnO composites at different concentrations was evaluated under solar simulated exposure of respective nanocomposite films. Nanocomposites were prepared by solid mixing using a cryogenic mill, and then films were prepared by compression molding. All films showed a good dispersion of ZnO nanoparticles without affect considerably the optical properties of the films. The films were exposed in a solar simulation chamber under three xenon arc lamps with a 340nm filter. Degradation of PP/ZnO nanocomposite films was monitored by formation of oxidative groups and changes on surface microstructure. FTIR results showed that oxidation groups in nanocomposites films increased by using cuasi-spherical ZnO nanoparticles.
Transition-metal functionalized-carbon nanotubes (CNTs) represent an important genre of hydrogen storage systems that exhibit superior storage capacity and improved storage kinetics when compared with the pristine CNTs. Here, we compare the reversible gravimetric hydrogen storage capacity of platinum-functionalized CNTs with that of pristine tubes, both measured at 300 K and an equilibrium hydrogen pressure of 1.67 MPa. The maximum reversible hydrogen storage capacity exhibited by the nano-composite material is found to be 3.2 ± 0.1 wt%, which is a nearly 50 % enhancement when compared with that of the pristine tubes. The enhanced hydrogen storage capacity of functionalized CNTs is attributed to the spill-over phenomena as suggested by the estimated storage capacity of Pt phase. The hydrogen storage in Pt nanoparticles modeled using the atomic magic number calculation and Pt hydride stoichiometry of PtH4 also suggests that nearly 15 closed shells of Pt atoms reversibly adsorb and spill hydrogen on to CNT binding sites.
Neutron diffraction was used to measure the residual stress distribution in an FeAl weld overlay on steel. It was found that the residual stresses accumulated during welding were essentially removed by the post-weld heat treatment that was applied to the specimen; most residual stresses in the specimen developed during cooling following the post-weld heat treatment. The experimental data were compared with a plasto-elastic finite element analysis. While some disagreement exists in absolute strain values, there is satisfactory agreement in strain spatial distribution between the experimental data and the finite element analysis.
We present a systematic analysis of SiOx alloys films containing Ge nanocrystals prepared by dc magnetron sputtering. Increasing the sputtering power (50–175W) reduces the average Ge nanocrystal size exponentially down to ∼2nm. Broad band photoluminescence spectra are observed in the visible at room temperature centered at ∼3eV or/and ∼2eV. Neither the 3eV nor the 2eV luminescence can be correlated to the change in the size. Excluding the quantum-confined origin, the presence of a luminescence center located in the inhomogeneous strain field of the Ge nanocrystal surface is discussed.
Amorphous SiOx alloys containing Ge or GeO2 nanocrystals are produced by dc-magnetron sputtering and controlled crystallization. The samples are investigated by Raman scattering, transmission electron microscopy, photo luminescence and excitation spectroscopy. Under UV excitation, both types of films luminesce around 3.1 eV, with identical PL line shapes and subnanosecond PL dynamics. The strongest PL intensity is found for the films containing GeO2 crystals and for the largest nanocrystals. These results are a clear indication that although the blue luminescence is without a doubt correlated with the formation of Ge (or GeO2) nanocrystals, it is not produced by the radiative recombination of excitons confined in the nanocrystals. Possible mechanisms for the luminescence are discussed, including defects at the nanocrystal/matrix interface or in the matrix itself.
The synthesis of nc-Si by reactive evaporation of SiO and subsequent thermal induced phase separation is reported. The size control of nc-Si is realized by evaporation of SiO/SiO2 superlattices. By this method an independent control of crystal size and density is possible. The phase separation of SiO into SiO2 and nc-Si in the limit of ultrathin layers is investigated. Different steps of this phase separation are characterized by photoluminescence, infrared absorption and transmission electron microscopy measurements. The strong room temperature luminescence of nc-Si shows a strong blueshift of the photoluminescence signal from 850 to 750 nm with decreasing crystal size. Several size dependent properties of this luminescence signal, like decreasing radiative lifetime and increasing no-phonon transition properties with decreasing crystal size are in good agreement with the quantum confinement model. Er doping of the nc-Si shows an enhancement of the Er luminescence at 1.54 μm by a factor of 5000 compared to doped SiO2 layers. The decreasing transfer time for the nc-Si to Er transition with decreasing crystal size can be understood as additional proof of increasing recombination probability within the nc-Si for decreasing crystal size.
Thin layers made of densely packed silicon nanocrystals sandwiched between amorphous silicon dioxide layers have been manufactured and characterized. An amorphous silicon/amorphous silicon dioxide superlattice is first grown by CVD or RF sputtering. The a-Si layers are recrystallized in a two-step procedure (nucleation + growth) to form layers of nearly identical nanocrystals whose diameter is given by the initial a-Si layer thickness. The recrystallization is monitored using a variety of techniques, including TEM, X-Ray, Raman, and luminescence spectroscopies. When the a-Si layer thickness decreases (from 25 nm to 2.5 nm) or the a-SiO2 layer thickness increases (from 1.5 nm to 6 nm), the recrystallization temperature increases dramatically compared to that of a single a-Si film. The removal of the a-Si tissue present between the nanocrystals, the passivation of the nanocrystals, and their doping are discussed.
The spherical indentation process has been modeled by the finite element method to study the pile-up behavior of elastic-plastic materials with different degrees of strain hardening. A wide range of materials was examined characterized by different elastic moduli, yield stresses, and strain hardening exponents. The geometry of the contact impressions was examined in both the loaded and unloaded conditions. Results show that pile-up behavior in elastic-plastic materials cannot be related solely to the strain hardening exponent, as has often been done in the past. Relating the pile-up behavior strictly to the strain hardening exponent may lead to significant errors in the calculated contact area for materials with modulus to yield stress ratio lower than 1000. In addition, an assessment of the combined influences of material properties and stage of development of the contact impression on the pile-up behavior is described.
Tungsten oxide nanorods (TONs) with the diameters of 40 nm and the length of 130 nm have been synthesized on substrates using two step electrochemical anodizing processes. The TONs were vertically well-ordered on the substrates with the average interdistance of 100 nm. The TONs had amorphous structure and was mainly composed of W, Al, and O elements, of which the contents varied gradually along the nanorod length from the top surface to the bottom. The cyclic voltammograms (CVs) and galvanostatic charge-discharge analyses showed that TONs had the typical electrochemical pseudocapacitive features of rectangular CV hysteresis and symmetric charge-discharge behaviors, respectively. When the TONs were heat-treated at 600℃ in vacuum, they showed the maximum specific capacitance of 660 ㎌/cm2, which was higher, by an order of magnitude, than that (68 ㎌/cm2) of the TONs annealed at 300 ℃ in ambient atmosphere.
Single-crystalline rock-salt PbS nanowires (NWs) were synthesized using three different routes; the solvothermal, chemical vapor transport, and gas-phase substitution reaction of pre-grown CdS NWs. They were uniformly grown with the  or ,  direction in a controlled manner. In the solvothermal growth, the oriented attachment of the octylamine (OA) ligands enables the NWs to be produced with a controlled morphology and growth direction. As the concentration of OA increases, the growth direction evolves from the  to the higher surface-energy  and  directions. In the synthesis involving chemical vapor transport and the substitution reaction, the use of a lower growth temperature causes the higher surface-energy growth direction to change from  to . We fabricated field effect transistors using single PbS NW, which showed intrinsic p-type semiconductor characteristics for all three routes. For the PbS NW with a thinner oxide layer, the carrier mobility was measured to be as high as 10 cm2V−1s−1.
The electronic properties of carbon nanotubes are quite often drastically affected by the presence of defects that can develop during nanotube growth, processing or characterization too. Some of these defects such as pentagon-heptagon rings, substitutional impurities, vacancies and dislocations are of topological nature, and can sometimes create on-tube intramolecular junctions, as found by previous scanning tunnelling microscopy studies.
Our recent STM experiments reveal for the first time a much more complicated junction structure, a hybrid single-walled carbon nanotube consisting of a distinct coiled structure located between two straight segments, each of different helicity. We characterise the hybrid junction at the atomic level and describe its electronic behaviour that has important implications in the practical design of functional components for nanoelectronic applications.
Molecular dynamics simulations of the flow of pressurised water through carbon nanotubes of chirality (9,0), (12,0), (15,0) and (18,0) have been undertaken at 298K with a water density of approximately 1240kg/m3. Results show that the rate of filling is least in the smallest diameter nanotube, but that there is less variation in the time taken to reach maximum occupancy. The water molecules are found to undergo restructuring due to their confinement, with detailed molecular arrangement dependent on CNT diameter. Enhanced rates of flow are shown for the (15,0) nanotube, highlighting the effect of nanotube diameter on confinement and thus on flow.
We report the fabrication of ferromagnetic NiFe nanotubes with a wall thickness of 80 nm by electrodeposition in nanoporous templates. The structure and wall thickness of the nanotubes are controlled by the thickness of the conductive layer at the back of the templates. The NiFe nanotubes have shown soft magnetic material properties with high magnetic saturation and low coercivity. The NiFe nanotube arrays are preferentially magnetized in the perpendicular direction to the nanotubes. Micromagnetic simulation results show that a curling mode is perceived with the formation of opposite magnetic vortex states on the end of the nanotube surface during the magnetization process.
The strength and electrical conductivity of Carbon Nanotube (CNT) yarns is dramatically affected by the handling of the material after the nanotubes are produced. Our nanotube production process involving Chemical Vapor Deposition (CVD) using the floating catalyst method produces a mass of entangled bundles of single-walled nanotubes in a gas suspension. Simply collecting and spinning this material produces a yarn with strength and electrical conductivity far less than the properties of the individual nanotubes due to the poor alignment of the bundles on the microscopic scale. We have developed methods of aligning the CNT material that are analogous to the techniques used in the textile industry for spinning staple yarns, but modified to be appropriate for nano-scale material. The result is a dramatic improvement in strength and electrical conductivity of our CNT yarns.
We have fabricated sub-100 nm triangles NiFe triangle arrays using NSL and the MOKE measurement and micromagnetic simulations were carried out to investigate the reversal mechanism of the arrays. Enhancement of coercivity compared to the thin film was observed in all the three arrays but in different degree from the MOKE measurement. With the increase of the lateral size of the triangle, the effect of the coercivity enhancing decreases. Micromagnetic simulation shows that instead of domain wall nucleation and annihilation in the thin film, the reversal mechanism of the 45 and 80 nm triangles is dominated by the coherent rotation. While in the 100 nm triangle, the magnetic reversal takes place via forming and reversing a V like sate.
Photoluminescence (PL) of nanocrystalline Si (nc-Si) assemblies formed by thermal crystallization of amorphous Si/SiO2 and SiO/SiO2 superlattices (SLs) has been investigated at different temperatures and excitation conditions. The low temperature resonant PL spectroscopy reveals phonon-assisted excitonic recombination. At room temperature the samples formed from a-SiO/SiO2 SLs possess relatively high PL quantum yield (∼ 1%). The PL transients have non-exponential decay, which indicates the exciton energy transfer in nc-Si ensembles. The excitonic energy of Er-doped nc-Si SL structures can be almost completely transferred to Er ions incorporated in SiO2 matrix that results in a strong emission line at 0.81 eV.