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Early weight trends after cardiac surgery in infants from low- and middle-income countries where the majority are undernourished have not been defined. We studied the early post-operative weight trends to identify specific factors associated with early weight loss and poor weight gain after discharge following congenital heart surgery in consecutive infants undergoing cardiac surgery at a referral hospital in Southern India.
This was a prospective observational study. Weights of the babies were recorded at different time points during the hospital stay and at 1-month post-discharge. A comprehensive database of pre-operative, operative, and post-operative variables was created and entered into a multivariate logistic regression analysis model to identify factors associated with excessive early weight loss after cardiac surgery, and poor weight gain following hospital discharge.
The study enrolled 192 infants (mean age 110.7 ± 99.9 days; weight z scores − 2.5 ± 1.5). There was a small but significant (p < 0.001) decline in weight in the hospital following surgery (1.6% decline (interquartile range −5.3 to +1.7)); however, there was substantial growth following discharge (26.7% increase (interquartile range 15.3–41.8)). The variables associated with post-operative weight loss were cumulative nil-per-oral duration and cardiopulmonary bypass time, while weight gain following discharge was only associated with age.
Weight loss is almost universal early after congenital heart surgery and is associated with complex surgery and cumulative nil-per-oral duration. After discharge, weight gain is almost universal and not associated with any of the perioperative variables.
Consumption of almonds has been shown to be associated with a decreased risk of CHD, which may be related to their fatty acid (FA) composition. However, the effect of almond consumption on the serum FA composition is not known. Therefore, in the present study, we investigated whether almond consumption would alter the serum FA profile and risk of CHD, as calculated using Framingham's 10-year risk score, in a dose-dependent manner in hyperlipidaemic individuals when compared with a higher-carbohydrate control group using dietary interventions incorporating almonds. A total of twenty-seven hyperlipidaemic individuals consumed three isoenergetic (mean 1770 kJ/d) supplements during three 1-month dietary phases: (1) full-dose almonds (50–100 g/d); (2) half-dose almonds with half-dose muffins; (3) full-dose muffins. Fasting blood samples were obtained at weeks 0 and 4 for the determination of FA concentrations. Almond intake (g/d) was found to be inversely associated with the estimated Framingham 10-year CHD risk score (P= 0·026). In both the half-dose and full-dose almond groups, the proportions of oleic acid (OA) and MUFA in the TAG fraction (half-almond: OA P= 0·003; MUFA P= 0·004; full-almond: OA P< 0·001; MUFA P< 0·001) and in the NEFA fraction (half-almond: OA P= 0·01; MUFA P= 0·04; full-almond: OA P= 0·12; MUFA P= 0·06) increased. The estimated Framingham 10-year CHD risk score was inversely associated with the percentage change of OA (P= 0·011) and MUFA (P= 0·016) content in the TAG fraction. The proportions of MUFA in the TAG and NEFA fractions were positively associated with changes in HDL-cholesterol concentrations. Similarly, the estimated Framingham 10-year CHD risk score was inversely associated with the percentage change of OA (P= 0·069) and MUFA content in the NEFA fraction (P= 0·009). In conclusion, the results of the present study indicate that almond consumption increases OA and MUFA content in serum TAG and NEFA fractions, which are inversely associated with CHD lipid risk factors and overall estimated 10-year CHD risk.
The cultivar Ajaya (IET 8585) exhibits durable broad-spectrum resistance to bacterial blight (BB) disease of rice and is widely used as a resistance donor. The present study was carried out to decipher the genetics of BB resistance in Ajaya and map the gene(s) conferring resistance. Genetic analysis in the F2 indicated a quantitative/additive nature of resistance governed by two loci with equal effects. Linked marker analysis and allelic tests revealed that one of the resistance genes is xa5. Sequence analysis of a 244 bp region of the second exon of the gene-encoding Transcription factor IIAγ (the candidate gene for xa5) confirmed the presence of xa5. Bulked-segregant analysis (BSA) revealed the putative location of the two quantitative trait loci (QTLs)/genes associated with resistance on chromosomes 5 and 8. Composite interval mapping located the first locus on Chr. 5S exactly in the genomic region spanned by xa5 and the second locus (qtl BBR 8.1) on Chr. 8L. Owing to its differential disease reaction with a set of seven hyper-virulent isolates of Xanthomonas oryzae, a map location on Chr. 8L, which was distinct from xa13 and data from allelism tests, the second resistance locus in Ajaya was determined to be novel and was designated as xaAj. A contig map spanning xaAj was constructed in silico and the genomic region was delimited to a 13·5 kb physical interval. In silico analysis of the genomic region spanning xaAj identified four putatively expressed candidate genes, one of which could be involved in imparting BB resistance in Ajaya along with xa5.
The sound emission from open turbulent flames is dictated by the two-point spatial correlation of the rate of change of the fluctuating heat release rate. This correlation in premixed flames can be represented well using Gaussian-type functions and unstrained laminar flame thermal thickness can be used to scale the correlation length scale, which is about a quarter of the planar laminar flame thermal thickness. This correlation and its length scale are observed to be less influenced by the fuel type or stoichiometry or turbulence Reynolds and Damkohler numbers. The time scale for fluctuating heat release rate is deduced to be about τc/34 on an average, where τc is the planar laminar flame time scale, using direct numerical simulation (DNS) data. These results and the spatial distribution of mean reaction rate obtained from Reynolds-averaged Navier–Stokes (RANS) calculations of open turbulent premixed flames employing the standard model and an algebraic reaction rate closure, involving a recently developed scalar dissipation rate model, are used to obtain the far-field sound pressure level from open flames. The calculated values agree well with measured values for flames of different stoichiometry and fuel types, having a range of turbulence intensities and heat output. Detailed analyses of RANS results clearly suggest that the noise level from turbulent premixed flames having an extensive and uniform spatial distribution of heat release rate is low.
Evolution of electronic devices towards higher performance and smaller size requires the passive components to be embedded within a printed wire board (PWB). A “film-on-foil” approach is the most viable fabrication method. A high permittivity of lead lanthanum zirconate titanate (PLZT) thin film was coated on nickel foil by chemical solution deposition. Such a prefabricated capacitor sheet can be embedded into a PWB. However, formation of a parasitic low-permittivity interfacial layer of nickel oxide during thermal processing of the PLZT films considerably reduces the capacitance density. To eliminate this parasitic effect, conductive buffer layer of lanthanum nickel oxide (LNO) was coated by chemical solution deposition on nickel foil. We produced PLZT film-on-foil capacitors with capacitance densities as high as 1.5 μF/cm2 and breakdown field strength >1.4 MV/cm. With the desirable volumetric character, PLZT film-on-foil capacitors hold particular promise for use in high voltage embedded passives.
Commission 36 covers all the physics of stellar atmospheres. The scientific activity in this large field has been very intense during the last triennium and led to the publication of a large number of papers which makes an exhaustive report practically not feasible. As a consequence we decided to keep the format of the preceding report: first a list of areas of current research, then web links for obtaining further information.
Thin films of BaCe0.8Y0.2O3-δ (BCY) were prepared by colloidal spray deposition. Dense, crack-free BCY films having a grain size of 2–7 μm were successfully deposited on NiO/BCY substrates. Electrochemical hydrogen pumping with the BCY films showed that the maximum current density increased with temperature. The maximum current density was sensitive to the moisture in the cathode gas; the value obtained with a dry cathode gas was only half that with a wet cathode gas. A very high hydrogen-pumping current density of 3.4 A/cm2 was measured at 700°C with an applied voltage of 1.5 V.
Dense ceramics with composition Ba(Ce0.7Zr0.2Yb0.1)O3-β (BCZY) were synthesized by solid state reactions, and their structures were characterized by Rietveld refinements of time-of-flight (TOF) neutron diffraction data collected for the samples at high-temperature and controlled atmospheres. The structure phase transition from orthorhombic Imma to cubic Pm3m was observed at the temperature between 500 and 700°C and in flowing 100ppm H2/Ar gases. At 900°C, the sample was subsequently exposed to different oxygen partial pressures (pO2, ranging from ∼10−17 to ∼10−23 atm) and water vapor pressures (pH2O) up to ∼0.18 atm. The expansion of lattice parameters of BCZY, instead of following the normally expected relationship with pO2, was actually correlated with the increase of pH2O, implying proton incorporation into the structures. The presence of H-containing species in the structure was confirmed by comparing both inelastic neutron scattering spectra and neutron diffraction data collected for dry and “wet” samples at 10K. The observed vibrational peaks at 104 and 150 meV and absence of a peak around 420 meV indicate the hydrogen occupation in the structure but the absence of any hydroxyl groups (hydrogen covalently bonded to oxygen). Electrical conductivities of BCZY were investigated at different temperatures in both dry and wet conditions.
Research on hydrogen separation membranes is motivated by the increasing demand for an environmentally benign, inexpensive technology for separating hydrogen from gas mixtures. Although most studies of hydrogen separation membranes have focused on proton-conducting oxides by themselves, the addition of metal to these oxides increases their hydrogen permeability and improves their mechanical stability. This study began by determining the electrical and hydrogen permeation properties of SrCe0.8Yb0.2O3−δ (SCYb). The results showed that the hydrogen permeation rate is limited by electron flow at the investigated temperatures (600 – 900°C). To further enhance hydrogen permeability, a cermet (i.e., ceramic-metal composite) membrane was made by adding Ni to the SCYb. The cermet showed no phase change after sintering in a reducing atmosphere. At 900°C, with 20% H2 /balance He as a feed gas (pH2O = 0.03 atm), the hydrogen permeation rate was 0.113 cm3/min-cm2 for Ni/SCYb (0.43-mm thick) and 0.008 cm3/min-cm2 for SCYb (0.7-mm thick). The dependences of hydrogen permeability on temperature, thickness, and hydrogen partial pressure gradients are also determined. The results demonstrate that adding Ni to SCYb considerably increases its hydrogen permeability by increasing its electron conductivity.
This paper reports the development of a DGPS navigation system integrated with altitude aiding. In this system, a digital height dataset is used for altitude augmentation. A two-dimensional (2-D) positioning algorithm is discussed and modified based on previous publications. The developed algorithm was implemented on the Brunel Inverse DGPS system. The performance of the new developed system is experimentally verified and compared with three-dimensional (3-D) GPS and DGPS systems. The experimental results showed 86% availability of positioning services; whereas for the 3-D GPS system alone, the availability was only 63% of time. In addition, the accuracy of the system was improved from 7.1 to 6.1 m (RMS) for GPS and from 6.0 to 5.1 m (RMS) for DGPS when compared to standalone 3-D modes.
Differential thermal analysis and thermogravimetric analysis (DTA/TGA) experiments have been completed in the BaF2-BaO-Y2O3-CuOx-H2O system at various oxygen pressures to determine the effect of adding solid BaF2and gaseous H2O (at pH2O = 2.5 kPa) on the eutectic melting in the system BaO-Y2O3-CuOx. We have investigated the eutectic melting temperature over the range of pO2 = 20 Pa to pO2 = 0.1 MPa under the following conditions: 1) without BaF2 or H2O; 2) with H2O only; 3) with BaF2 only; 4) with both BaF2 and H2O. Results indicate that without BaF2 or H2O, eutectic melting is depressed from 917°C at pO2 = 0.1 MPa to 838°C at pO2 = 1 kPa. At oxygen pressures below 1 kPa, down to pO2 = 20 Pa, no further lowering of eutectic melting temperature was observed. The topologies of the temperature vs. log pO2 curves for various combinations of BaF2 and H2O were similar to that for the experiments without BaF2 or H2O, but all curves were shifted to lower temperatures. For the experiments with addition of BaF2 only, H2O only, and BaF2 with H2O, the eutectic melting temperatures as a function of pO2 were lowered by, respectively, 5°C - 15°C, 15°C - 25°C and 20°C - 30°C. Application of results to the “BaF2ex-situ” method of processing Ba2YCu3Ox coated conductors is discussed.
The synthesis at high pressures ( ∼60 Kbar) and high temperatures (∼1100 °C) of the title new ruthenates has been achieved and the materials compared to the gadolinium analogue. The structure remains tetragonal (S.G. P4/mmm) and the cell parameters linearly decrease following the lanthanide contraction. Preliminary results concerning the complex magnetic properties of these materials, where superconductivity, antiferromagnetism and a superimposed ferromagnetic ordering coexist, are presented.
The ac magnetic losses at power frequencies (60 Hz) were investigated for mono- and multifilament Ag-sheathed (Bi, Pb)2Sr2Ca2Cu3Oy (BSCCO-2223) tapes with similar Ic values at 77 K. The multifilament sample exhibited higher losses than the monofilament under the same conditions. Loss peaks are discussed in terms of intergranular, intragranular, and eddy current losses. Because of BSCCO's anisotropy, field orientation has a large effect on the magnitude of these peaks, even at relatively small angles. Losses for fields applied parallel to the c-axis of the textured BSCCO grains are larger by over an order of magnitude than those applied perpendicular.
The subsolidus phase relationships of the high-Tc 2223 superconductor in the (Bi, Pb)–Sr–Ca–Cu–O (BSCCO) system have been examined at 810–820 °C. All experiments were carried out at ambient pressure in a 7.5% O2 (92.5% Ar) atmosphere. Eleven phases were found to exist in equilibrium with the 2223 phase. These 11 phases include CuO and 10 oxide solid solutions. From among these phases, a total of 48 five-phase combinations including the 2223 and 2212 phases were investigated experimentally, and 16 equilibrium assemblages were found which define a multicomponent compositional space corresponding to the 2223 + 2212 solid-state compatibility region. The subsolidus data form a partial basis for future investigation of the Pb-2223 primary phase field.
Mixed-conducting ceramic oxides have potential uses in high-temperature electrochemical applications such as solid oxide fuel cells, batteries, sensors, and oxygen-permeable membranes. The Sr-Fe-Co-O system combines high electronic/ionic conductivity with appreciable oxygen permeability at elevated temperatures. Dense ceramic membranes made of this material can be used to separate high-purity oxygen from air without the need for external electrical circuitry, or to partially oxidize methane to produce syngas. Samples of Sr2Fe3-xCoxOy (with x = 0,0.6,1.0, and 1.4) were prepared by solid-state reaction method in atmospheres with various oxygen partial pressures (pO2) and were characterized by X-ray diffraction, scanning electron microscopy, and electrical conductivity testing. Phase components of the sample are dependent on cobalt concentration and pO2. Electrical conductivity increases with increasing temperature and cobalt content in the material.
The potential applications of mixed-conducting ceramic oxides include solid-oxide fuel cells, rechargeable batteries, gas sensors and oxygen-permeable membranes. Several perovskite-derived mixed Sr-Fe-Co oxides show not only high electrical-conductivity but also appreciable oxygen-permeability at elevated temperatures. For example, dense ceramic membranes of SrFeCo0.5O3-δ can be used to separate oxygen from air without the need for external electrical circuitry. The separated oxygen can be directly used for the partial oxidation of methane to produce syngas. Quantitative phase analysis of the SrFeCo0.5O3-δ material has revealed that it is predominantly composed of two Sr-Fe-Co-O systems, Sr4Fe6-xCoxO13 and SrFe1−xCoxO3-δ. Here we report preliminary structural findings on the SrFe1−xCoxO3-δ (0 ≤ x ≥ 0.3) system.
Directional solidification has been shown to be a successful way of achieving high current densities in bulk YBCO. The lack of understanding of the growth kinetics, however, makes it difficult to fabricate longer samples and reduce the processing times. To study the growth kinetics, quenching experiments of undoped YBa2Cu3O7−x (Y-123) and Y-123 doped with Pt and Nd from above the peritectic temperature with different holding times, t, were conducted. The results of these experiments indicate that the average 211 particle size varies at t1/3. Growth rate experiments were also conducted on these samples to determine the maximum growth rate for plane front solidification, Rmax. This quantity was measured for undoped and doped Y-123, and it was found that the addition of Pt did not increase Rmax while the addition of Nd doubled the growth rate. Using the coarsening results together with the growth rate experiments, the diffusivity of Y in liquid and the 211-liquid interfacial energy for undoped and doped Y-123 were calculated.
Sufficient conditions are derived for the relative controllability of nonlinear neutral Volterra integrodifferential systems with distributed delays in the control variables. The results are a generalization of previous results and are obtained by using Schauder's fixed-point theorem.