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Postoperative cognitive impairment is among the most common medical complications associated with surgical interventions – particularly in elderly patients. In our aging society, it is an urgent medical need to determine preoperative individual risk prediction to allow more accurate cost–benefit decisions prior to elective surgeries. So far, risk prediction is mainly based on clinical parameters. However, these parameters only give a rough estimate of the individual risk. At present, there are no molecular or neuroimaging biomarkers available to improve risk prediction and little is known about the etiology and pathophysiology of this clinical condition. In this short review, we summarize the current state of knowledge and briefly present the recently started BioCog project (Biomarker Development for Postoperative Cognitive Impairment in the Elderly), which is funded by the European Union. It is the goal of this research and development (R&D) project, which involves academic and industry partners throughout Europe, to deliver a multivariate algorithm based on clinical assessments as well as molecular and neuroimaging biomarkers to overcome the currently unsatisfying situation.
The functional composition of plant communities in montane regions has been studied for decades, and most recent analyses find that environmentally favourable landscapes at lower altitudes tend to be dominated by species with resource-acquisitive traits, while more resource-conservative taxa dominate higher-altitude communities. However, it is unclear the extent to which this pattern is driven by co-gradient variation within clades or changes in clade representation across the gradient. To test for co-gradient variation, species composition, phylogenetic structure and functional traits were quantified for 97 species within the plant family Melastomataceae at five locations across a 2500-m altitudinal gradient along Volcán Barva in Costa Rica. Average melastome leaf force to punch, specific leaf area and leaf size vary with altitude, while four other functional traits do not. Taxonomic dissimilarity between communities was correlated with altitudinal difference, while phylogenetic dissimilarity was correlated with altitudinal dissimilarity only when measured with a metric that emphasizes shallow turnover of the tips of the phylogeny. These results highlight how species turnover may be more pronounced than functional or phylogenetic variation along altitudinal gradients. In addition, these results highlight the conservation value of lowland tropical forests, which here harbour a disproportionate amount of phylogenetic and functional diversity.
We compared rotavirus detection patterns before (2001–2006) and after (2008–2015) rotavirus vaccine introduction. We also compared rotavirus detection patterns in odd (2009, 2011, 2013, 2015) and even (2008, 2010, 2012, 2014) years post-vaccine separately. Results of stool rotavirus antigen testing from inpatient, outpatient and emergency department encounters from July 2000 to July 2015 at two paediatric hospital laboratories in Atlanta, Georgia were reviewed. Post-vaccine, rotavirus detection declined (30.2% vs. 13.7% (overall 54.6% decline, P <0.001)), occurred more frequently outside the rotavirus season (19.8% vs. 3.5%; P < 0.001), and was more common among older children (26 vs. 13 median months of age; P < 0.001). During odd years post-vaccine, rotavirus detection was significantly higher than even years (20.2% vs. 6.4%; P < 0.001). Rotavirus detection declined substantially and developed a biennial pattern in the post-vaccine era. The intensity and temporality of rotavirus detection in odd years post-vaccine resembled that observed pre-vaccine, although considerably reduced in magnitude.
A number of laser facilities coming online all over the world promise the capability of high-power laser experiments with shot repetition rates between 1 and 10 Hz. Target availability and technical issues related to the interaction environment could become a bottleneck for the exploitation of such facilities. In this paper, we report on target needs for three different classes of experiments: dynamic compression physics, electron transport and isochoric heating, and laser-driven particle and radiation sources. We also review some of the most challenging issues in target fabrication and high repetition rate operation. Finally, we discuss current target supply strategies and future perspectives to establish a sustainable target provision infrastructure for advanced laser facilities.
Restriction enzyme fingerprints were generated from purified plasmid DNA from 324 clinical isolates that belonged to 7 enterobacterial genera and 88 single plasmids in Escherichia coli K12 according to the following strategy.
Purified plasmid DNA was digested with PstI. The number of fragments detected in a 0·8 agarose gel was used to determine which 2 of 6 restriction enzymes including Pstl was most likely to provide a fingerprint comprising sufficient fragments to ensure specificity but sufficiently few to allow easy visual assessment and minimize coincidental matching. When PstI produced > 20 fragments, Eco RI and HindIII were used; when PstI generated < 6 fragments Bsp 1286 and AvaII were used and SmaI was employed when between 6 and 20 fragments were obtained from PstI digests. Using a minimum of 12 fragments from a combination of 2 enzymes as the criterion for characterizing a strain/plasmid, satisfactory 2-enzyme fingerprints were obtained from 87% of the strains and plasmids studied using PstI and no more than two additional enzymes per strain. Of the remaining 54 strains, 51 harboured only small plasmids (< 10 kb) and 3 produced satisfactory fingerprints when digested with a fourth enzyme.
Four hundred and seven clinical isolates of Escherichia coli were examined for the presence of plasmids. These isolates comprised 189 which were collected irrespective of antimicrobial resistance (VP) and 218 which were collected on the basis of high-level trimethoprim resistance (TPR). The VP isolates were divided into drug sensitive (VPS) and drug-resistant (VPR) subpopulations.
Plasmids were detected in 88% of VP isolates (81% of VPS and 94% of VPR) and 98% of TPR isolates. The distribution of plasmids in both groups and subpopulations was very similar. However, there were small but statistically significant differences between the plasmid distributions. These showed that more isolates in the resistant groups harboured plasmids than in the sensitive subpopulation (VPS) and that the number of plasmids carried by resistant isolates was greater. Multiple drug resistance was significantly more common among TPR isolates than the VPR subpopulation and this was paralleled by increased numbers of plasmids.
Fifty-eight per cent of VPR and 57% of TPR isolates transferred antimicrobial resistance and plasmids to E. coli K12. Of the R+ isolates, 60% carried small plasmids (MW < 20Md) and 52% of these co-transferred with R-plasmids. These results are discussed.
Purpose: To evaluate the role of retrograde urethrography in treatment planning for salvage external beam radiotherapy in patients with increasing prostate-specific antigen levels after radical prostatectomy.
Methods and Materials: From July 1988 to December 2002, 173 consecutive patients received external beam radiotherapy for increasing prostate-specific antigen levels after radical prostatectomy. All 173 simulation films were reviewed, and retrograde urethrography was performed in 148 patients (86%). The distance between the line connecting the lower poles of the ischial tuberosities and site of abrupt narrowing of contrast material was measured in all 148 patients. This distance was compared with that measured in 148 consecutive patients with intact prostates who had retrograde urethrography while undergoing treatment planning for definitive radiotherapy.
Results: The mean (median) distance from the line connecting the lower poles of the ischial tuberosities to the abrupt narrowing seen in the urethrogram in patients with increasing prostate-specific antigen levels was 1.54cm (1.50cm) compared with 1.73cm (1.80cm) in those with intact prostates (p = 0.0145).
Conclusion: Retrograde urethrography is important in treatment planning for salvage radiotherapy of the prostate bed after radical prostatectomy to adequately treat the apex of the prostate bed.
Cratylia argentea (Desv.) O. Kuntze is a drought-tolerant tropical shrub legume that can help to ensure continuity of forage supply in smallholder systems either through direct grazing or as a cut-and-carry plant for fresh foliage or silage. A collection of 38 accessions was characterized agronomically and nutritionally. High diversity was detected between accessions. Time to flowering ranged from 217–329 days after transplanting seedlings to the field and from 129–202 days after cutting. Flowering is probably induced by reduction of day length. Seed production was high but variable. Dry matter production ranged from 190–382 g/plant in the rainy and from 124–262 g/plant in the dry season, content of in vitro digestible dry matter from 589–690 g/kg, crude protein content from 184–237 g/kg and fibre content from 403–528 g/kg (neutral detergent fibre, NDF), 240–335 g/kg (acid detergent fibre, ADF), and 9–13 g/kg (acid detergent fibre-bound nitrogen, N-ADF). Accessions CIAT 18674 and CIAT 22406 were identified as promising for further study. They were superior to the commercial cultivar in terms of dry matter (DM) production, particularly in the dry season. Further research is required to determine the prevailing reproduction strategy of C. argentea and to quantify outcrossing-rates. Multilocational trials with a selected set of accessions should be conducted under different environmental conditions.
NGC 5102 has an unusually low number of XRBs. The deficit of LMXBs is even more striking because some of these sources may in fact be HMXBs, produced in one of the two recent bursts of star formation $\sim$15 and $\sim$300 Myr ago. Our UV-optical spectral synthesis analysis demonstrates that a significant fraction ($>$50%) of the stars in this galaxy are comparatively young ($<$3 Gyr). NGC 5102 also has an usually low number of globular clusters for its mass, luminosity and environment.
We discuss the relationship between the XRB population, the globular cluster population and the relative youth of the majority of the stars in this galaxy. We intend to extend our investigation of the relationship between XRB populations, star-formation history and globular clusters to a sample of ten early-type galaxies with a range of star-formation histories and investigate the implications for models of LMXB formation and evolution.
This work presents a novel approach using supercritical carbon dioxide (SCCO2) to selectively extract poly(propylene glycol) (PPG) porogen from a poly(methylsilsesquioxane) (PMSSQ) matrix, which results in the formation of nanopores. Nanoporous thin films were prepared by spin-casting a solution containing appropriate quantities of PPG porogen and PMSSQ dissolved in PM acetate. The as-spun films were thermally cured at temperatures well below the thermal degradation temperature of the organic polymer to form a cross-linked organic/inorganic polymer hybrid. By selectively removing the CO2 soluble PPG porogen, open and closed pore structures are possible depending upon the porogen load and its distribution in the matrix before extraction. In the present work, two different loadings of PPG namely 25 wt.% and 55 wt.% were used. Both static SCCO2 and pulsed SCCO2/cosolvent treatments were used for PPG extraction. The initial results indicate that the pulsed SCCO2/cosolovent treatment was more efficient. Fourier transform infrared spectroscopy (FTIR) and refractive index measurements further corroborate the successful extraction of the porogens at relatively low temperatures (2000C). For the pure PMSSQ film, the k value is 3.1, whereas it is 1.46 and 2.27 for the open and closed pore compositions respectively after the static SCCO2 extraction and 430°C subsequent annealing. The reduction in the k-value is attributed to the formation of nanopores. The pore structure was verified from transmission electron microscopy (TEM), and from small-angle x-ray scattering (SAXS) measurements, the pore size was determined to be 1-3 nm for these films.
We have shown previously the results from out-of-plane and in-plane X-ray scattering /diffraction measurements together with transmission electron microscope and X-ray reflectance measurements and shown that they are effective in characterization of a periodic porous silica low-k film . In the present work, we report the results on pore-size distribution, pore-diameter anisotropy, and size and macroscopic isotropy of domain structure.
Adhesion property of Cu film on a low-k material was investigated. The low-k films deposited using a mixture of hexamethyldisilane(HMDS) and para-xylene had a dielectric constant as low as 2.7 and thermal stability up to 400°C. In this work, Ti glue layer, boron dopant, and N2 plasma treatment were applied to improve adhesion between Cu and the low-k films. Adhesion property was significantly enhanced by N2 plasma-treatment on the low-k film and boron dopant in Cu film. This enhanced adhesion was attributed to the formation of new binding states between Ti and the plasma-treated surface of the low-k film and to the diffusion of B from Cu to Ti and low-k films. Cu(B)/Ti/low-k film annealed at 350°C withstood an applied load of about 23 N during the scratch test.
A trench-first dual damascene process has been developed for fat wires (1.26 μm pitch, 1.1 μm thickness) in a 0.18 μm CMOS process with copper/fluorosilicate glass (FSG) interconnect technology. The process window for the patterning of vias in such deep trenches depends on the trench depth and on the line width of the trench, with the worse case being an intermediate line width (lines that are 3X the via diameter). Compared to a single damascene process, the dual damascene process has comparable yield and reliability, with lower via resistance and lower cost.
We discuss two themes from Chandra cluster observations. First, we describe the interaction of buoyant, radio emitting plasma bubbles with the hot intracluster gas. Second we summarize the Chandra observations of “cold” fronts (sharp discontinuities in gas density and temperature) separating cool, denser gas clouds from the hotter intracluster medium.
In this study we present investigation on the anelastic behavior of sputtered 1 [.proportional]m thin Cu films. Most of the literature that reports on the mechanical properties of thin metallic films is based on substrate curvature measurements. We have developed a new version of a bulge tester that combines the capacitive measurement of the bulge deflection of a membrane with a resonance frequency measurement of the residual stress in the membrane. A Cu membrane is plastically deformed to a pre-determined strain by controlled gas-pressure bulging of the membrane. After the bulging stress is removed, the residual tensile stress, which has been decreased by the plastic deformation, is then determined by measuring the resonant frequency as a function of time. Immediately after plastic straining, the residual (tensile) stress of membranes was observed to increase. At room temperature a maximum stress was typically reached in the order of an hour. At still longer times the stress decreased again as a result of creep. The transient increase in stress following plastic straining grew larger as the amount of plastic strain produced by bulging was increased. With higher temperatures the transient became both faster and larger. A model is presented that based on the mechanism of thermally activated glide separates the microstructure in a class of “soft” and “hard” grains solving the issue of an “apparent” increase in strain energy as a function of time after deformation.
Very fine-grained Ni and Cu films were formed using pulsed laser deposition onto fused silica substrates. The grain sizes in the films were characterized by electron microscopy, and the mechanical properties were determined by ultra-low load indentation, with finite-element modeling used to evaluate the properties of the layers separately from those of the substrate. Some Ni films were also examined after annealing to 350 and 450°C to enlarge the grain sizes. These preliminary results show that the observed hardnesses are consistent with a simple extension of the Hall-Petch relationship to grain sizes as small as 11 nm for Ni and 32 nm for Cu.
The influence of Cu on the response of Al-Cu thin films to thermally induced stress is studied. The copper concentration is varied between 0 and 1.15 at. %. It is proposed that copper atoms which have not formed precipitates, largely affect the mechanical behaviour. This idea is supported by the following observations. An isothermal hold results in temporary strengthening of the films. The extent of this strengthening increases with copper concentration, increases with decreasing isothermal hold temperature and saturates with increasing isothermal hold period. Based on these observations the large tensile stress increase below 200 °C is ascribed to the formation of Cottrell atmospheres.
It is well known that the mechanical properties of thin films depend critically on film thickness However, the contributions from film thickness and grain size are difficult to separate, because they typically scale with each other. In one study by Venkatraman and Bravman, Al films, which were thinned using anodic oxidation to reduce film thickness without changing grain size, showed a clear increase in yield stress with decreasing film thickness.
We have performed a similar study on both electroplated and sputtered Cu films by using chemical-mechanical polishing (CMP) to reduce the film thickness without changing the grain size. Stress-temperature curves were measured for both the electroplated and sputtered Cu films with thicknesses between 0.1 and 1.8 microns using a laser scanning wafer curvature technique. The yield stress at room temperature was found to increase with decreasing film thickness for both sets of samples. The sputtered films, however, showed higher yield stresses in comparison to the electroplated films. Most of these differences can be attributed to the different microstructures of the films, which were determined by focused ion beam (FIB) microscopy and x-ray diffraction.