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Rules of thumb (RoTs) are proposed as a means of promoting higher levels of Defined Contribution (DC) pension saving and to help stimulate debate about the high and uncertain cost of pension provision, leading to the development of solutions. The Lifetime Pension Contribution (LPC) tells young people what pension contribution is required over a full working life to achieve a decent retirement income, calculated as 23% of average UK earnings. Another RoT is that each 1% of earnings provides a pension of 1.5% of earnings. Other RoTs show how costs vary by retirement age and if the saverʼs retirement planning is on track. The current high cost of pensions is partly due to low interest rates and the inefficiencies of the DC market, with inadequate bulk purchasing power and risk sharing. RoTs might help encourage higher employer contributions, either through automatic enrolment or on a voluntary basis.
Breastfeeding may reduce obesity risk, but this association could be confounded by breastfeeding families’ characteristics. We investigated if body composition differs at birth among infants who were either exclusively breast- or formula-fed. We hypothesized the two groups would differ in body composition, even at birth, prior to their post-natal feeding experience. Healthy primiparous carrying singleton pregnancy were recruited at 15 weeks’ gestation. PEA POD® measured body composition within 72 hours of delivery and infant feeding was prospectively captured. Out of the 1,152 infants recruited, 117 (10.2%) and 239 (20.7%) went on to be either exclusively breast- or formula-fed, respectively. Breastfed infants were heavier at birth, but their percentage fat mass (FM) was lower than that of exclusively formula-fed infants (covariate adjusted β = −1.91 percentage points of FM; 95% CI −2.82 to −1.01). Differences in intra-uterine exposures, irrespective of early diet, may partly explain an infant’s obesity risk.
The novel Volumetric Image Matching Environment for Radiotherapy (VIMER) was developed to allow users to view both computed tomography (CT) and cone-beam CT (CBCT) datasets within the same 3D model in virtual reality (VR) space. Stereoscopic visualisation of both datasets combined with custom slicing tools and complete freedom in motion enables alternative inspection and matching of the datasets for image-guided radiotherapy (IGRT).
Material and methods:
A qualitative study was conducted to explore the challenges and benefits of VIMER with respect to image registration. Following training and use of the software, an interview session was conducted with a sample group of six university staff members with clinical experience in image matching.
User discomfort and frustration stemmed from unfamiliarity with the drastically different input tools and matching interface. As the primary advantage, the users reported match inspection efficiency when presented with the 3D volumetric renderings of the planning and secondary CBCT datasets.
This study provided initial evidence for the achievable benefits and limitations to consider when implementing a 3D voxel-based dataset comparison VR tool including a need for extensive training and the minimal interruption to IGRT workflow. Key advantages include efficient 3D anatomical interpretation and the capability for volumetric matching.
The binary X-ray source GX 1 + 4 was observed during a balloon flight in 1986, November. The source was in a relatively high intensity state. Time analysis of the data shows that the pulsation period was 111.8 ± 1.0 s indicating that one or more episodes of spin-down occurred between 1980 and 1986. Folded pulse profiles are very broad with an indication of a notch at the peak. Evidence has been found for a correlation between hard X-ray intensity and phase of the proposed 304 day orbital period. The time averaged intensity since 1980 is an order of magnitude lower than during the 1970’s. A survey of the post 1980 data shows that several reversals of the period derivative have occurred. Spin-up at the rates typical of the 1970’s has been followed by a dramatic spin-down episode with dP/dt>2.4 × 10−7 s/s.
Dansgaard–Oeschger (D–O) cycles had far-reaching effects on Northern Hemisphere and tropical climate systems during the last glacial period, yet the climatic response to D–O cycles in western North America is controversial, especially prior to 55 ka. We document changes in precipitation along the western slope of the central Sierra Nevada during early Marine Oxygen Isotope Stages (MIS) 3 and 4 (55–67 ka) from a U-series dated speleothem record from McLean's Cave. The timing of our multi-proxy geochemical dataset is coeval with D–O interstadials (15–18) and stadials, including Heinrich Event 6. The McLean's Cave stalagmite indicates warmer and drier conditions during Greenland interstadials (GISs 15–18), signified by elevated δ18O, δ13C, reflectance, and trace element concentrations, and less radiogenic 87Sr/86Sr. Our record extends evidence of a strong linkage between high-latitude warming and reduced precipitation in western North America to early MIS 3 and MIS 4. This record shows that the linkage persists in diverse global climate states, and documents the nature of the climatic response in central California to Heinrich Event 6.
Native to temperate South America, deeproot sedge has naturalized throughout the southeastern United States. Often forming dense, homogenous stands, deeproot sedge has become widespread, invasive, and potentially harmful ecologically throughout the coastal prairie ecoregion of Texas. Possessing characteristics (rapid growth, generalized habitat requirements) of other weedy congeners (purple nutsedge and yellow nutsedge), its relatively recent expansion highlights the critical need to develop effective control techniques and strategies for this species throughout this endangered ecoregion. Research was performed to delineate total nonstructural carbohydrate (TNC) trends in deeproot sedge rhizomes for development of a phenologically based schedule for herbicide applications and mechanical treatments. Overall, TNC levels were greatest in May to August and lowest from October to January, regardless of study area. Apparently, deeproot sedge exerts little energy into seed production because TNC levels were continually replenished throughout the growing season. As such, foliar-herbicide application throughout the growing season should achieve total plant kill. Conversely, deeproot sedge rhizome TNC levels never fell below 30%, even during winter, which indicates that winter mechanical treatments or winter prescribed fires will not be effective because substantial rhizome reserves are present to support resprouting during the next growing season. Beyond a priori prevention, sequential herbicide applications combined with integrated, sequential, prescribed fire and herbicide treatments will be needed for long-term deeproot sedge control throughout its geographic range.
Visually coupled systems such as helmet mounted displays are designed to improve aircrew situational awareness by providing timely flight, targeting and other information overlaid on real or sensor-derived views of the external environment. Data can be presented in monocular, biocular or binocular fashion and are associated with visual conflicts and potential ophthalmic problems. Restricted sensor spectrum, limits of resolution, inherent system latency, the displaced visual input from remote sensors and restricted field of view may contribute to ophthalmic symptoms in aircrew. Disruption to binocularity and reliance on monocular cues for depth perception and hyperstereopsis from sensor-induced convergence disparity may cause distance estimation problems, whereas inappropriate accommodative stimuli and ocular dominance factors are common causes of eyestrain. Binocular rivalry from discordant imagery to each eye may compromise visual performance via several mechanisms. This article discusses the potential visual problems associated with visually coupled systems and the challenges of integrating complex systems with the aircrew interface.
We are developing a purely commensal survey experiment for fast (<5 s) transient radio sources. Short-timescale transients are associated with the most energetic and brightest single events in the Universe. Our objective is to cover the enormous volume of transients parameter space made available by ASKAP, with an unprecedented combination of sensitivity and field of view. Fast timescale transients open new vistas on the physics of high brightness temperature emission, extreme states of matter and the physics of strong gravitational fields. In addition, the detection of extragalactic objects affords us an entirely new and extremely sensitive probe on the huge reservoir of baryons present in the IGM. We outline here our approach to the considerable challenge involved in detecting fast transients, particularly the development of hardware fast enough to dedisperse and search the ASKAP data stream at or near real-time rates. Through CRAFT, ASKAP will provide the testbed of many of the key technologies and survey modes proposed for high time resolution science with the SKA.
The IntCal09 and Marine09 radiocarbon calibration curves have been revised utilizing newly available and updated data sets from 14C measurements on tree rings, plant macrofossils, speleothems, corals, and foraminifera. The calibration curves were derived from the data using the random walk model (RWM) used to generate IntCal09 and Marine09, which has been revised to account for additional uncertainties and error structures. The new curves were ratified at the 21st International Radiocarbon conference in July 2012 and are available as Supplemental Material at www.radiocarbon.org. The database can be accessed at http://intcal.qub.ac.uk/intcal13/.
High-quality data from appropriate archives are needed for the continuing improvement of radiocarbon calibration curves. We discuss here the basic assumptions behind 14C dating that necessitate calibration and the relative strengths and weaknesses of archives from which calibration data are obtained. We also highlight the procedures, problems, and uncertainties involved in determining atmospheric and surface ocean 14C/12C in these archives, including a discussion of the various methods used to derive an independent absolute timescale and uncertainty. The types of data required for the current IntCal database and calibration curve model are tabulated with examples.
We present a solution to the problem of denning a counterpart in Algebraic Set Theory of the construction of internal sheaves in Topos Theory. Our approach is general in that we consider sheaves as determined by Lawvere-Tierney coverages, rather than by Grothendieck coverages, and assume only a weakening of the axioms for small maps originally introduced by Joyal and Moerdijk, thus subsuming the existing topos-theoretic results.
A new method is proposed to determine the elastic modulus and residual stress of freestanding thin films based on nanoindentation techniques. The experimentally measured stiffness-displacement response is applied to a simple membrane model that assumes the film deformation is dominated by stretching as opposed to bending. Dimensional analysis is used to identify appropriate limitations of the proposed model. Experimental verification of the method is demonstrated for Al/0.5 wt% Cu films nominally 22 µm wide, 0.55 µm thick, and 150, 300, and 500 µm long. The estimated modulus for the four freestanding films match the value measured by electrostatic techniques to within 2%, and the residual stress to within 19.1%. The difference in residual stress can be completely accounted for by thermal expansion and a modest change in temperature of 3 °C. Numerous experimental pitfalls are identified and discussed. Collectively, these data and the technique used to generate them should help future investigators make more accurate and precise measurements of the mechanical properties of freestanding thin films using nanoindentation.
For many years, a fundamental problem in contact mechanics, both tribology and indentation problems, has been the inability to see what is taking place—the buried-interface problem. Over the past few years, there have been developments whereby it has become possible to perform contact mechanics experiments in situ within a transmission electron microscope. These new experiments have been enabled by both the miniaturization of sensors and actuators and improvements in their mechanical stability and force sensitivity. New information is now becoming available about the nanoscale processes of sliding, wear, and tribochemical reactions, as well as microstructural evolution during nanoindentation such as dislocation bursts and phase transformations. This article provides an overview of some of these developments, in terms of both the advances in technical instrumentation and some of the novel scientific insights.
Damage of the intestinal epithelial barrier by xenobiotics or reactive oxygen species and a dysregulated immune response are both factors involved in the pathogenesis of inflammatory bowel diseases (IBD). Curcumin and rutin are polyphenolic compounds known to have antioxidant and anti-inflammatory activities, but their mechanism(s) of action are yet to be fully elucidated. Multidrug resistance gene-deficient (mdr1a− / − ) mice spontaneously develop intestinal inflammation, predominantly in the colon, with pathology similar to IBD, so this mouse model is relevant for studying diet–gene interactions and potential effects of foods on remission or development of IBD. The present study tested whether the addition of curcumin or rutin to the diet would alleviate colonic inflammation in mdr1a− / − mice. Using whole-genome microarrays, the effect of dietary curcumin on gene expression in colon tissue was also investigated. Twelve mice were randomly assigned to each of three diets (control (AIN-76A), control +0·2 % curcumin or control +0·1 % rutin) and monitored from the age of 7 to 24 weeks. Curcumin, but not rutin, significantly reduced histological signs of colonic inflammation in mdr1a− / − mice. Microarray and pathway analyses suggested that the effect of dietary curcumin on colon inflammation could be via an up-regulation of xenobiotic metabolism and a down-regulation of pro-inflammatory pathways, probably mediated by pregnane X receptor (Pxr) and peroxisome proliferator-activated receptor α (Ppara) activation of retinoid X receptor (Rxr). These results indicate the potential of global gene expression and pathway analyses to study and better understand the effect of foods in modulating colonic inflammation.