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Early replacement of a new central venous catheter (CVC) may pose a risk of persistent or recurrent infection in patients with a catheter-related bloodstream infection (CRBSI). We evaluated the clinical impact of early CVC reinsertion after catheter removal in patients with CRBSIs.
We conducted a retrospective chart review of adult patients with confirmed CRBSIs in 2 tertiary-care hospitals over a 7-year period.
To treat their infections, 316 patients with CRBSIs underwent CVC removal. Among them, 130 (41.1%) underwent early CVC reinsertion (≤3 days after CVC removal), 39 (12.4%) underwent delayed reinsertion (>3 days), and 147 (46.5%) did not undergo CVC reinsertion. There were no differences in baseline characteristics among the 3 groups, except for nontunneled CVC, presence of septic shock, and reason for CVC reinsertion. The rate of persistent CRBSI in the early CVC reinsertion group (22.3%) was higher than that in the no CVC reinsertion group (7.5%; P = .002) but was similar to that in the delayed CVC reinsertion group (17.9%; P > .99). The other clinical outcomes did not differ among the 3 groups, including rates of 30-day mortality, complicated infection, and recurrence. After controlling for several confounding factors, early CVC reinsertion was not significantly associated with persistent CRBSI (OR, 1.59; P = .35) or 30-day mortality compared with delayed CVC reinsertion (OR, 0.81; P = .68).
Early CVC reinsertion in the setting of CRBSI may be safe. Replacement of a new CVC should not be delayed in patients who still require a CVC for ongoing management.
This study aimed to investigate the influences of age, education, and gender on the two total scores (TS-I and TS-II) of the Consortium to Establish a Registry for Alzheimer's Disease Neuropsychological assessment battery (CERAD-NP) and to provide normative information based on an analysis for a large number of elderly persons with a wide range of educational levels.
In the study, 1,987 community-dwelling healthy volunteers (620 males and 1,367 females; 50–90 years of age; and zero to 25 years of education) were included. People with serious neurological, medical, and psychiatric disorders (including dementia) were excluded. All participants underwent the CERAD-NP assessment. TS-I was generated by summing raw scores from the CERAD-NP subtests, excluding Mini-Mental State Examination and Constructional Praxis (CP) recall subtests. TS-II was calculated by adding CP recall score to TS-I.
Both TS-I and TS-II were significantly influenced by demographic variables. Education accounted for the greatest proportion of score variance. Interaction effect between age and gender was found. Based on the results obtained, normative data of the CERAD-NP total scores were stratified by age (six overlapping tables), education (four strata), and gender.
The normative information will be very useful for better interpretation of the CERAD-NP total scores in various clinical and research settings and for comparing individuals’ performance of the battery across countries.
Increasing number of massive globular clusters (GCs) in the Milky Way are now turned out to host multiple stellar populations having different heavy element abundances enriched by supernovae. Recent observations have further shown that [CNO/Fe] is also enhanced in metal-rich subpopulations in most of these GCs, including ω Cen and M22 (Marino et al. 2011, 2012). In order to reflect this in our population modeling, we have expanded the parameter space of Y2 isochrones and horizontal-branch (HB) evolutionary tracks to include the cases of normal and enhanced nitrogen abundances ([N/Fe] = 0.0, 0.8, and 1.6). The observed variations in the total CNO content were reproduced by interpolating these nitrogen enhanced stellar models. Our test simulations with varying N and O abundances show that, once the total CNO sum ([CNO/Fe]) is held constant, both N and O have almost identical effects on the HR diagram (see Fig. 1).
We investigated the pressure dependence of the inductive coupled plasma (ICP) oxidation on the electrical characteristics of the thin oxide films. Activation energies and electron temperatures with different pressures were estimated. To demonstrate the pressure effect on the plasma oxide quality, simple N type metal-oxide-semiconductor (NMOS) transistors were fabricated and investigated in a few electrical properties. At higher pressure than 200mTorr, plasma oxide has a slightly higher on-current and a lower interfacial trap density. The on-current gain seems to be related to the field mobility increase and the lower defective interface to the electron temperature during oxidation.
An attempt was made to predict the macroscopic plastic flow of a high-performance pipeline steel, consisting of dual constituent phases (soft ferrite and hard bainite), by performing nanoindentation experiments on each microphase with two spherical indenters that have different radii (550 nm and 3.3 μm). The procedure is based on the well known concepts of indentation stress-strain and constraint factor, which make it possible to relate indentation hardness to the plastic flow of the phases. Additional consideration of the indentation size effect for sphere and application of a simple “rule-of-mixture” led us to a reasonably successful estimation of the macroscopic plastic flow of the steel from the microphases properties, which was verified by comparing the predicted stress-strain curve with that directly measured from the conventional tensile test of a bulky sample.
The low frequency noise of individual ZnO nanowire (NW) field effect transistors (FETs) exposed to air is systematically characterized. The measured noise power spectrum shows a classical 1/f type. The noise amplitude is independent of source-drain current and inversely proportional to gate voltage. The extracted Hooge's constant of ZnO NW is found to be 6.52×10−3. In addition, the low frequency noise of ZnO NW according to NW resistance and contact property are investigated. The noise amplitude is proportional to the square of ZnO NW resistance. If a sample shows a nonlinear current-voltage (I-V) characteristic due to a poor electrical contact, the noise power spectrum is proportional to the third power of current instead of the square of current.
Field effect transistors(FETs) made of ZnO nanowires are very sensitive to the gas environment, so that the passivation can be a good way to get reliable nanowire FETs with longer lifetime and the better mobility. The studies on the passivation effects with the positive electron-beam resist was investigated by selectively covering the part of nanowire devices between the electrodes. Reproducible electrical characteristics were recorded, reflecting the stable electrical properties by the passivation which deters the degradation of a device. Considering the defect states of oxide nanowires dominate the charge states, the pre-state just before the passivation process will be crucial to understand the reproducible and controllable device characteristics of nanowire devices.
A top gate pentacene TFT employing vapor deposited polyimide as a gate dielectric was fabricated. Polyimide was co-evaporated from 6FDA and ODA monomers and annealed at 150 °C in vacuum. The degree of imidization was verified by FT-IR. A breakdown voltage of 0.9 MV/cm of polyimide film was measured by MIM structure. A top gate pentacene TFT with W/L=25 has 0.01 cm2/Vs as a mobility, about 103 as an on-off ratio (In/off), −7.5V as a threshold voltage and 9 V per decade as a sub-threshold slope.
III-nitride films were grown on the corrugated interface substrate using a metalorganic chemical vapor deposition system to increase the optical power of white LEDs. The patterning of a substrate for enhancing the extraction efficiency was processed using an inductively coupled plasma reactive ion etching system and the surface morphology of the etched sapphire wafer and that of the non-etched one were investigated using an atomic force microscope. The structural and optical properties of GaN on CIS were characterized by a high-resolution x-ray diffraction, transmission electron microscopy, AFM and photoluminescence. The roughness of the etched sapphire wafer was higher than that of the non-etched one. The GaN layer didn't grow locally over the surface of the cone shape pattern. The reason is that (0001) c-plane which is favor for GaN growth doesn't exist on the cone shape patterned region. The lateral growth of the GaN layer that was initially grown on the (0001) c-plane among pattern regions, was enhanced by raising the growth temperature and lowering the reactor pressure, resulting in the smooth surface over the pattern region. The (102) FWHM of GaN layer on the patterned substrate was better than that of GaN on the conventional substrate and no defect was detected at the interface of the cone shape pattern. The optical power of the LED on the patterned substrate was 20% higher than that on the conventional substrate due to the increased extraction efficiency.
Incomplete reprogramming of the donor cell nucleus after nuclear transfer (NT) probably leads to the abnormal expression of developmentally important genes. This may be responsible for the low efficiency of cloned animal production. Insulin-like growth factor 2 (IGF2) and IGF2 receptor (IGF2R) are imprinted genes that play important roles in preimplantation development. To obtain an insight into abnormal gene expression after nuclear transfer, we assessed the transcription patterns of IGF2-IGF2R in single in vitro fertilised and cloned embryos by reverse-transcription polymerase chain reaction (RT-PCR). IGF2R expression did not differ significantly but IGF2 was more highly expressed in cloned embryos than in IVF embryos (p < 0.05). This was confirmed by a quantitative RT-PCR method. Thus, incomplete reprogramming may induce abnormal transcription of IGF2 in cloned embryos.
Silicon nitride with the aligned reinforcing grains was prepared by tape casting with addition of the silicon nitride whiskers and gas-pressure sintering at 2148 K. The microstructure and the mechanical properties of the sintered sample, including the fracture toughness and the three-point flexural strength, were highly anisotropic. Both the fracture toughness and the flexural strength were the highest when the crack-propagation direction was normal to the alignment direction. This result was interpreted from the laminate composite materials’ point of view. Although the large elongated grains were as long as 44.4 ± 12 μm and as wide as 5.1 ± 0.67 μm, they were not the fracture origins.
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