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This study aimed to examine the predictors of cognitive performance in patients with pediatric mild traumatic brain injury (pmTBI) and to determine whether group differences in cognitive performance on a computerized test battery could be observed between pmTBI patients and healthy controls (HC) in the sub-acute (SA) and the early chronic (EC) phases of injury.
203 pmTBI patients recruited from emergency settings and 159 age- and sex-matched HC aged 8–18 rated their ongoing post-concussive symptoms (PCS) on the Post-Concussion Symptom Inventory and completed the Cogstate brief battery in the SA (1–11 days) phase of injury. A subset (156 pmTBI patients; 144 HC) completed testing in the EC (∼4 months) phase.
Within the SA phase, a group difference was only observed for the visual learning task (One-Card Learning), with pmTBI patients being less accurate relative to HC. Follow-up analyses indicated higher ongoing PCS and higher 5P clinical risk scores were significant predictors of lower One-Card Learning accuracy within SA phase, while premorbid variables (estimates of intellectual functioning, parental education, and presence of learning disabilities or attention-deficit/hyperactivity disorder) were not.
The absence of group differences at EC phase is supportive of cognitive recovery by 4 months post-injury. While the severity of ongoing PCS and the 5P score were better overall predictors of cognitive performance on the Cogstate at SA relative to premorbid variables, the full regression model explained only 4.1% of the variance, highlighting the need for future work on predictors of cognitive outcomes.
Our recent studies based on a large sample of K giants with Hipparcos parallaxes and spectroscopic analysis resulted more than a dozen new Li-rich K giants including few super Li-rich ones. Most of the Li-rich K giants including the new ones appear to occur at the luminosity bump in the HR diagram. However, one can’t rule out the possibility of overlap with the clump region where core He-burning K giants reside post He-flash at the tip of RGB. It is important to distinguish field K giants of clump from the bump region in the HR diagram to understand clues for Li production in K giants. In this poster, we explore whether GAIA parallaxes improve to disentangle clump from bump region, more precisely.
We present results of chemical abundance study of a few representative stellar streams of Galactic thick and thin discs. Arcturus stream, which was proposed to have an extragalactic origin, and a recently detected stream called AF06 were studied. Results show a range of metallicity, age and abundance pattern that are consistent with those of Galactic thick disc component. We found similar results for AF06. The abundance and age results unambiguously rule out the possibility that the member stars are vestiges of open clusters. Abundance results of a sample of stars of Sirius and Hercules streams combined with the kinematics show that both the streams belong to the thin disc component. Also, results rule out these are remnants of open clusters. It is likely these streams formed insitu due to perturbations caused by non-axisymmetric components such as bar or spirals.
The Dawn spacecraft orbited Asteroid (4) Vesta for a year, and returned disk-resolved images and spectra covering visible and near-infrared wavelengths at scales as high as 20 m/pix. The visible geometric albedo of Vesta is ~ 0.36. The disk-integrated phase function of Vesta in the visible wavelengths derived from Dawn approach data, previous ground-based observations, and Rosetta OSIRIS observations is consistent with an IAU H-G phase law with H=3.2 mag and G=0.28. Hapke's modeling yields a disk-averaged single-scattering albedo of 0.50, an asymmetry factor of -0.25, and a roughness parameter of ~20 deg at 700 nm wavelength. Vesta's surface displays the largest albedo variations observed so far on asteroids, ranging from ~0.10 to ~0.76 in geometric albedo in the visible wavelengths. The phase function of Vesta displays obvious systematic variations with respect to wavelength, with steeper slopes within the 1- and 2-micron pyroxene bands, consistent with previous ground-based observations and laboratory measurement of HED meteorites showing deeper bands at higher phase angles. The relatively high albedo of Vesta suggests significant contribution of multiple scattering. The non-linear effect of multiple scattering and the possible systematic variations of phase function with albedo across the surface of Vesta may invalidate the traditional algorithm of applying photometric correction on airless planetary surfaces.
The Rank Forum on Vitamin D was held on 2nd and 3rd July 2009 at the University of Surrey, Guildford, UK. The workshop consisted of a series of scene-setting presentations to address the current issues and challenges concerning vitamin D and health, and included an open discussion focusing on the identification of the concentrations of serum 25-hydroxyvitamin D (25(OH)D) (a marker of vitamin D status) that may be regarded as optimal, and the implications this process may have in the setting of future dietary reference values for vitamin D in the UK. The Forum was in agreement with the fact that it is desirable for all of the population to have a serum 25(OH)D concentration above 25 nmol/l, but it discussed some uncertainty about the strength of evidence for the need to aim for substantially higher concentrations (25(OH)D concentrations>75 nmol/l). Any discussion of ‘optimal’ concentration of serum 25(OH)D needs to define ‘optimal’ with care since it is important to consider the normal distribution of requirements and the vitamin D needs for a wide range of outcomes. Current UK reference values concentrate on the requirements of particular subgroups of the population; this differs from the approaches used in other European countries where a wider range of age groups tend to be covered. With the re-emergence of rickets and the public health burden of low vitamin D status being already apparent, there is a need for urgent action from policy makers and risk managers. The Forum highlighted concerns regarding the failure of implementation of existing strategies in the UK for achieving current vitamin D recommendations.
Electron backscatter diffraction (EBSD) analysis of monazite requires a comparison of empirically collected electron backscatter patterns (EBSPs) with theoretical diffraction data, or ‘match units’, derived from known crystallographic parameters. Published crystallographic data derived from compositionally varying natural and synthetic monazite are used to calculate ten different match units for monazite. These match units are used to systematically index EBSPs obtained from four natural monazite samples with different compositions. Analyses of EBSD data, derived from the indexing of five and six diffraction bands using each of the ten match units for 10,000 EBSPs from each of the four samples, indicate a large variation in the ability of the different match units to correctly index the different natural samples. However, the use of match units derived from either synthetic Gd or Eu monazite crystallographic data yield good results for three of the four analysed monazites. Comparison of sample composition with published monazite compositions indicates that these match units are likely to yield good results for the EBSD analysis of metamorphic monazite. The results provide a clear strategy for optimizing the acquisition and analysis of EBSD data from monazite but also indicate the need for the collection of new crystallographic structure data and the subsequent generation of more appropriate match units for natural monazite.
B. E. Reddy, Indian Institute of Astrophysics, Bangalore, India,
D. L. Lambert, McDonald Observatory and Department of Astronomy, University of Texas, Austin, TX, USA,
C. Allende Prieto, McDonald Observatory and Department of Astronomy, University of Texas, Austin, TX, USA
We present the results of our recent abundance survey of the Galactic thick disk. We selected from the Hipparcos catalog 176 sample stars satisfying the following criteria: they are nearby (d ≤ 150 pc) subgiants and dwarfs, of spectral types F and G, and with thick-disk kinematics (VLSR ≤ −40 kms−1, │WLSR│ ≤ 30 kms−1). Assuming that the velocity distribution of each stellar population is Gaussian, we assigned stars with a probability P ≤ 70% to one of the three components. This resulted in 95 thick-disk stars, 17 thin-disk stars, and 24 halo stars. The remaining 40 objects cannot be unambiguously assigned to one of the three components.
We derived abundances for 23 elements from C to Eu. The thick-disk abundance patterns are compared with earlier results from the thin-disk survey of Reddy et al. (2003). The levels of α-elements (O, Mg, Si, Ca, and Ti), thought to be produced dominantly in Type-ii supernovae, are enhanced in thick-disk stars relative to the values found for thin-disk members in the range −0.3 > [Fe/H] > −1.2. The scatter in the abundance ratios [X/Fe] at a given [Fe/H] for thick-disk stars is consistent with the predicted dispersion due to measurement errors, as is the case for the thin disk, suggesting a lack of “cosmic” scatter. The observed compositions seem consistent with a model of galaxy formation by mergers in a ∧ CDM universe.
Sol-gel derived Nb2O5 thin films were intercalated with Mg2+,using the non-aqueous solution of Mg(ClO4)2 in propylene carbonate (pc) as the electrolyte. 2% and 4% ( volume %) water was added to the electrolyte to study the effect of water on the electrochromic properties of Nb2O5. This paper presents the changes in optical and structural properties of the intercalated films with and without water in the electrolyte. The ratio (x) of the Mg2+ and Nb atoms has been controlled by optimizing the intercalation duration under a constant current density. The fall in transmittance on intercalation (for x= 0.8) increased by 15% with 4% water in the electrolyte, compared to the film intercalated without water. FTIR studies show that water is incorporated in the films on intercalation and small quantities of Mg(OH)2 and Nb-OH are formed along with Mg-O-Nb bonds. The presence of water in electrolyte decreases water content in the films and enhances the formation of Mg(OH)2, Mg-O-Nb and Nb-OH bonds. The recovery of Mg2+ on deintercalation is slightly reduced in presence of water in the electrolyte. The cyclic stability of the films intercalated without water is more than that of the films intercalated in presence of water.
Background: Pleural effusions after bidirectional cavopulmonary anastomosis remain a significant cause of morbidity. Prolonged effusions in such patients have been associated with persistent elevations in plasma renin and angiotensin II. Methods: We conducted a controlled study in 36 patients (median age 8 months) undergoing bidirectional cavopulmonary anastomosis. Enalapril (5 mcg/kg) was administered intravenously within 1 hour of surgery and every 12 hours thereafter in 18 patients; when these patients were tolerating feeds, enalapril was switched to enteral captopril (3 mg/kg/day) every 8 hours. The other 18 patients did not receive perioperative angiotensin converting enzyme inhibitors. Using standardized criteria for discontinuation of chest tubes (< 2 mL/kg/day), volume and duration of pleural drainage were compared between groups. Results. There were no differences between groups in demographic, diagnostic, or hemodynamic factors. There was no difference in cardiopulmonary bypass time between groups and no difference in postoperative pulmonary arterial pressures. The duration of pleural drainage was shorter (2.2 ± 1.4 vs 5.9 ± 1.4 days, p< 0.001) and the volume less during the first 24 hours (4.7 ± 1.2 vs 7.7 ± 2.1 mL/kg, p< 0.001) and overall (10.6 ± 2.4 vs 19.6 ± 4.5 mL/kg, p< 0.001) in patients who received angiotensin converting enzyme inhibitors than those who did not. Readmission for persistent effusions was required in 3 patients who did not receive angiotensin converting enzyme inhibitors and none who did (p= 0.11). Conclusions. Perioperative administration of angiotensin converting enzyme inhibitors is associated with decreased severity and duration of pleural effusions following bidirectional cavopulmonary anastomosis.
Septorhinoplasty is a very common operation in otolaryngological practice. We report the second case of a carotico-cavernous fistula following septorhinoplasty. This case presented with very severe epistaxis before the appearance of the typical pulsating exophthalmos, ophthalmoplegia, headache and engorged veins on the right side of the face. Our case was treated by endovascular thrombosis with electrolytically detachable coils.
An abundance analysis of the photosphere of the F-type Post-AGB candidate IRAS 05341-+0852 is presented. It shows that the star is metal-poor ([Fe/H]=–1.0) and carbon-rich (C/0≈2.2). Carbon, nitrogen, oxygen, silicon, and possibly lithium and aluminum are found to be over abundant. Most importantly this star has large overabundance of s-process elements which are as follows: [Y/Fe]= 1.80, [Ba/Fe]= 2.58, [La/Fe]= 2.86, [Ce/Fe]= 2.95, [Pr/Fe]= 2.27, [Nd/Fe]= 1.97, and [Sm/Fe]= 0.86. The overabundances of s-process elements and carbon in IRAS 05341+0852 is direct evidence for the association of s-process enhancements with shell-flashes and dredge-up. These are likely responsible for the increase in C/O. The possible overabundance of Li ([Li/Fe]≤2.5) and Al ([Al/Fe]≤ 1.1) in IRAS 05341+0852 could indicate that there was Hot Bottom Burning (HBB), where the base of the convective envelope is hot enough for nucleosynthesis to occur (Lattanzio 1993). HBB has been suggested as the mechanism responsible for the production of Li in the Li-rich AGB stars discovered by Smith and Lambert (1989). In fact these are bright AGB stars which are oxygen-rich rather than carbon-rich. Recent calculations by Sackmann and Boothroyd (1992) showed that Li-rich and O-rich AGB stars are the result of HBB. In the HBB models temperatures of the order of 0.5–1 × 108 K are encountered at the base of the convective envelope (Blöcker and Schönberner 1991). This is hot enough for the reaction 25Mg(p,γ) 26 Al resulting in the production of Al.
CCD imaging and BVRI photometry of 14 IRAS sources with far-IR colours similar to planetary nebulae and post-AGB stars are presented. Also results of optical and near-IR spectroscopy of 10 of these candidates are given. Based on the spectral energy distribution from 0.4 μm to 100 μm, the sample of program stars are put into two groups. The sources IRAS 08187-1905, IRAS 05238-0626 and IRAS 17086-2403 present similar flux distributions. These three sources have detached cold dust components with dust radii Rd ≈ 1000 R∗. The low infrared variability of theses sources suggests that the intense mass loss has been ceased. All three sources are at high galactic latitude (1>9°) suggesting that these are old low-mass evolved stars. In the IRAS colour-colour diagram of Likkel et al (1991) these sources fall in the region where most of the stars are evolved stars and PNe but without CO detection. This is consistent with at least one source IRAS 17086-2403, in which OH and CO molecular features are not detected. The far-IR excess, non-variability and high latitude of these objects suggest that these are post-AGB supergiants, slowly evolving towards planetary nebula phase.
High chemical purity is essential for achieving satisfactory device yield in submicron CMOS processing. Reprocessing of liquid chemicals to maintain high purity can drastically reduce both environmental impact and cost of ownership (CoO) of wafer cleaning operations. We propose the use of a novel membrane Filter technology for control of contamination spikes and reduction of liquid chemical usage in pre‐gate HF cleaning. To ensure filter effectiveness, we have developed an in‐process sensor that monitors solution cleanliness by measuring the deposition rate of reducible ions on silicon. Metals are detected through their effect on the surface recombination of photoexcited carriers. This detection method allows quantification of copper and noble metal ions down to 108 atoms/cm2 levels. We have investigated the effect of chemical purity during HF cleaning on the gate oxide integrity (GOI) of 70–200 Å gate oxides. A significant increase in the low‐field breakdown is observed for HF‐last cleaning using chemicals containing more than 10 ppt Cu. We present the results of Cu spiking experiments to evaluate our ability to quantify contamination down to the stringent levels required for an industrial scale wet‐bench. We observe a linear correlation between metal deposition rate and Cu concentration in the 1–5 ppb range.
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