1,198 research outputs found
Influence of Soybean Oil or Non-Soybean Oil Based Lipid Emulsions on Parenteral Nutrition Associated Liver Disease in Late Preterm and Term Infants
Background: Total parenteral nutrition (TPN) is a life-saving therapy given to neonates with intestinal failure. However, infants on long-term TPN may experience Parenteral Nutrition-Associated Liver Disease (PNALD). New formulations for lipid emulsions are purportedly better than the traditional soy-based lipid emulsions (SLE). Our primary objective was to determine the prevalence of PNALD in infants who received non-soybean-based lipid emulsions (NSLE) or SLE.
Methods:Â In this retrospective study, medical records of all infants admitted to a tertiary neonatal intensive care unitfrom 2004 to 2013 were reviewed. Late preterm (34 -36 weeks of gestation) and term infants who were on TPN for more than two weeks were included. Their demographic data and clinical variables were collected.
Results: 208 infants received SLE for more than two weeks. The prevalence rate of PNALD in those who received SLE was 21% while that of those who received the NSLE was 17%. No significant difference was found between the ‘Soy’ or ‘NonSoy’ subgroups (p = 0.315). Seventy infants received TPN for more than four weeks. The prevalence rate of PNALD in infants who received SLE and NSLE was 35% and 25% respectively. No significant statistical difference was found between the ‘Soy’ or ‘NonSoy’ subgroups (p = 0.132).
Conclusions: The type of lipid emulsion does not significantly influence the rate of PNALD in late preterm and term infants on long-term TPN
Interactive three-dimensional boundary element stress analysis of components in aircraft structures
Computer aided design of mechanical components is an iterative process that often involves multiple stress analysis runs; this can be time consuming and expensive. Significant efficiency improvements can be made by increasing interactivity at the conceptual design stage. One approach is through real-time re-analysis of models with continuously updating geometry. Thus each run can benefit from an existing mesh and governing boundary element matrix that are similar to the updated geometry. For small problems, amenable to real-time analysis, re-integration accounts for the majority of the re-analysis time. This paper assesses how efficiency can be achieved during re-integration through both algorithmic and hardware based methods. For models with fewer than 10,000 degrees of freedom, the proposed algorithm performs up to five times faster than a standard integration scheme. An additional six times speed is achieved on eight cores over the serial implementation. By combining this work with previously addressed meshing and solution schemes, real-time re-analysis becomes a reality for small three-dimensional problems. Significant acceleration of larger systems is also achieved. This work demonstrates the viability of application in the aerospace industry where rapid validation of a range of similar models is an essential tool for optimising aircraft designs
Structural and electrical properties of c-axis oriented Y1-xCaxBa2(Cu1-yZny)3O7-delta thin films grown by pulsed laser deposition
Ca- and Zn-subsituted Y1-xCaxBa2(Cu1-yZny)O7-delta (x = 0, 0.05 and y = 0,
0.02, 0.04, 0.05) thin films were grown on SrTiO3 (100) substrates using the
pulsed laser deposition (PLD) technique. Effects of various growth parameters
on the quality of the film were studied via X-ray diffraction (XRD), atomic
force microscopy (AFM), and in-plane resistivity, rhoab(T), measurements. The
deposition temperature and oxygen partial pressure were gradually increased to
820C and 1.20 mbar respectively. Films grown under these conditions exhibited
good c-axis orientation (primarily limited by the grain size) and low values of
the extrapolated residual resistivity, rho(0), at zero temperature. The planar
hole content, p, was determined from the room temperature thermopower, S[290K],
measurements and the effects of oxygen annealing were also studied. Fully
oxygenated samples were found to be overdoped with p ~ 0.195. The
Superconducting transition temperature Tc(p), and rho(T,p) showed the expected
systematic variations with changing Zn content.Comment: Submitted to Physica C (2003
Localized surface states in HTSC: Alternative mechanism of zero-bias conductance peaks
It is shown that the quasiparticle states localized in the vicinity of
surface imperfections of atomic size can be responsible for the zero-bias
tunneling conductance peaks in high-Tc superconductors. The contribution from
these states can be easily separated from other mechanisms using their
qualitatively different response on an external magnetic field.Comment: REVTeX, 4 pages, 2 figs; to be published in PR
Synchronization in a System of Globally Coupled Oscillators with Time Delay
We study the synchronization phenomena in a system of globally coupled
oscillators with time delay in the coupling. The self-consistency equations for
the order parameter are derived, which depend explicitly on the amount of
delay. Analysis of these equations reveals that the system in general exhibits
discontinuous transitions in addition to the usual continuous transition,
between the incoherent state and a multitude of coherent states with different
synchronization frequencies. In particular, the phase diagram is obtained on
the plane of the coupling strength and the delay time, and ubiquity of
multistability as well as suppression of the synchronization frequency is
manifested. Numerical simulations are also performed to give consistent
results
Evidence for hadronic deconfinement in -p collisions at 1.8 TeV
We have measured deconfined hadronic volumes, fm,
produced by a one dimensional (1D) expansion. These volumes are directly
proportional to the charged particle pseudorapidity densities . The hadronization temperature is (syst)
MeV. Using Bjorken's 1D model,the hadronization energy density is (stat) GeV/fm corresponding to an excitation of (stat) quark-gluon degrees of freedom.Comment: 15 pages, 3 figures, 2 table
The effect of Zn substitution on the state of oxygen deficiency and hole concentration in Y1-xCaxBa2(Cu1-yZny)3O7-d
We have investigated the effect of Zn substitution on the hole content, p,
and the oxygen deficiency, d, for a series of high-quality crystalline c-axis
oriented thin films and polycrystalline Y1-xCaxBa2(Cu1-yZny)3O7-delta compounds
over a wide range of composition (x, y, and delta). p was determined from the
room-temperature thermopower, S[290K]. When annealed at a given temperature and
oxygen partial pressure, a small but systematic variation in S[290K] was
observed with Zn, for all the samples. From the analysis of the temperature
derivative of resistivity, drho/dT, at 300K, which varies almost linearly with
p, irrespective of the composition of the sample, and the thermo-gravimetric
analysis (TGA), we have found that annealing under identical conditions makes
the Zn-substituted compounds somewhat more oxygen deficient compared to the
Zn-free ones
High Pressure Thermoelasticity of Body-centered Cubic Tantalum
We have investigated the thermoelasticity of body-centered cubic (bcc)
tantalum from first principles by using the linearized augmented plane wave
(LAPW) and mixed--basis pseudopotential methods for pressures up to 400 GPa and
temperatures up to 10000 K. Electronic excitation contributions to the free
energy were included from the band structures, and phonon contributions were
included using the particle-in-a-cell (PIC) model. The computed elastic
constants agree well with available ultrasonic and diamond anvil cell data at
low pressures, and shock data at high pressures. The shear modulus and
the anisotropy change behavior with increasing pressure around 150 GPa because
of an electronic topological transition. We find that the main contribution of
temperature to the elastic constants is from the thermal expansivity. The PIC
model in conjunction with fast self-consistent techniques is shown to be a
tractable approach to studying thermoelasticity.Comment: To be appear in Physical Review
Influence of impurity scattering on tunneling conductance in normal metal- d -wave superconductor junctions
Tunneling conductance spectra between a normal metal / d-wave superconductor
junction under the presence of bulk impurities in the superconductor are
studied. The quasiclassical theory has been applied to calculate the spatial
variation of the pair potential and the effect of impurity scattering has been
introduced by t-matrix approximation. The magnitude of a subdominant s-wave
component at the interface is shown to robust against the impurity scattering
while that for a subdominant -wave component is largely suppressed with
the increase of the impurity scattering rate. The zero-bias conductance peak
due to the zero-energy Andreev bound states is significantly broadened for the
case of Born limit impurity compared with that of unitary limit impurity.Comment: 14 pages, 5 figure
<i>Pseudomonas aeruginosa</i> intensive care unit outbreak:winnowing of transmissions with molecular and genomic typing
Bioinformatics and computational biology analyses were supported by the University of St Andrews Bioinformatics Unit which is funded by a Wellcome Trust ISSF award [grant 097831/Z/11/Z]. BJP, KO, MP, MTGH, GP and SHG are funded by the Chief Scientist Office through the Scottish Infection Research Network, a part of the SHAIPI consortium grant reference number SIRN/10.Background: Pseudomonas aeruginosa healthcare outbreaks can be time consuming and difficult to investigate. Guidance does not specify which typing technique is most practical to base decisions on. Aim: We explore the usefulness of whole genome sequencing (WGS) in the investigation of a Pseudomonas aeruginosa outbreak describing how it compares with pulsed-field gel electrophoresis (PFGE) and variable number tandem repeat (VNTR) analysis. Methods: Six patient isolates and six environmental samples from an Intensive Care Unit (ICU) positive for P. aeruginosa over two years underwent VNTR, PFGE and WGS. Findings:Â VNTR and PFGE were required to fully determine the potential source of infection and rule out others. WGS results unambiguously distinguished linked isolates giving greater assurance of the transmission route between wash hand basin (WHB) water and two patients supporting control measures employed. Conclusion:Â WGS provided detailed information without need for further typing. When allied to epidemiological information it can be used to understand outbreak situations rapidly and with certainty. Implementation of WGS in real-time would be a major advance in day-to-day practice. It could become a standard of care as it becomes more widespread due to its reproducibility and reduction in costs.Publisher PDFPeer reviewe
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