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The present study evaluates the use of multiple correspondence analysis (MCA), a type of exploratory factor analysis designed to reduce the dimensionality of large categorical data sets, in identifying behaviours associated with measures of overweight/obesity in Vanuatu, a rapidly modernizing Pacific Island country.
Starting with seventy-three true/false questions regarding a variety of behaviours, MCA identified twelve most significantly associated with modernization status and transformed the aggregate binary responses of participants to these twelve questions into a linear scale. Using this scale, individuals were separated into three modernization groups (tertiles) among which measures of body fat were compared and OR for overweight/obesity were computed.
Ni-Vanuatu adults (n 810) aged 20–85 years.
Among individuals in the tertile characterized by positive responses to most of or all the twelve modernization questions, weight and measures of body fat and the likelihood that measures of body fat were above the US 75th percentile were significantly greater compared with individuals in the tertiles characterized by mostly or partly negative responses.
The study indicates that MCA can be used to identify individuals or groups at risk for overweight/obesity, based on answers to simply-put questions. MCA therefore may be useful in areas where obtaining detailed information about modernization status is constrained by time, money or manpower.
Sleep disturbance is common on in-patient psychiatry wards. This study explored subjective and objective patterns of sleep disturbance and contributory environmental factors. Participants were recruited from mental health acute admission wards and had a range of subjective and objective assessments of sleep. Light intensity and noise levels were measured to characterise potential environmental causes for poor sleep.
We recruited 20 patients; 15% were high risk for obstructive sleep apnoea. Nineteen participants reported poor sleep quality on the Pittsburgh Sleep Quality Index, and 90% had significant sleep fragmentation with objective measures. Inside light levels were low (day <200 lux and night <10 lux). Night sound levels were 40–90 db.
Sleep disturbance was highly prevalent. Increased awareness of sleep disorders is needed. Modifiable environmental factors on the ward were implicated, therefore increased awareness and a change of approach to sleep disturbance in in-patient psychiatry is recommended.
Measurement error in self-reported total sugars intake may obscure associations between sugars consumption and health outcomes, and the sum of 24 h urinary sucrose and fructose may serve as a predictive biomarker of total sugars intake.
The Study of Latinos: Nutrition & Physical Activity Assessment Study (SOLNAS) was an ancillary study to the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) cohort. Doubly labelled water and 24 h urinary sucrose and fructose were used as biomarkers of energy and sugars intake, respectively. Participants’ diets were assessed by up to three 24 h recalls (88 % had two or more recalls). Procedures were repeated approximately 6 months after the initial visit among a subset of ninety-six participants.
Four centres (Bronx, NY; Chicago, IL; Miami, FL; San Diego, CA) across the USA.
Men and women (n 477) aged 18–74 years.
The geometric mean of total sugars was 167·5 (95 % CI 154·4, 181·7) g/d for the biomarker-predicted and 90·6 (95 % CI 87·6, 93·6) g/d for the self-reported total sugars intake. Self-reported total sugars intake was not correlated with biomarker-predicted sugars intake (r=−0·06, P=0·20, n 450). Among the reliability sample (n 90), the reproducibility coefficient was 0·59 for biomarker-predicted and 0·20 for self-reported total sugars intake.
Possible explanations for the lack of association between biomarker-predicted and self-reported sugars intake include measurement error in self-reported diet, high intra-individual variability in sugars intake, and/or urinary sucrose and fructose may not be a suitable proxy for total sugars intake in this study population.
Eddington is a space mission for extrasolar planet finding and for asteroseismic observations. It has been selected by ESA as an F2/F3 reserve mission with a potential implementation in 2008-13. Here we describe Eddington's capabilities to detect extrasolar planets, with an emphasis on the detection of habitable planets. Simulations covering the instrumental capabilities of Eddington and the stellar distributions in potential target fields lead to predictions of about 10,000 planets of all sizes and temperatures, and a few tens of terrestrial planets that are potentially habitable. Implications of Eddington for future larger scale missions are briefly discussed.
Since the date of the 1935 Paris meeting two total eclipses have been successfully observed. Throughout the long path crossing Siberia and Japan the weather on June 19, 1936 on the whole about lived up to predictions. On account of widely scattered clouds neighbouring expeditions had quite different luck with the weather. In contrast, the June 8, 1937 eclipse was seen throughout the whole track under universally clear skies, which is all the more surprising for the reason that eclipse expeditions to the tropics usually fare badly with the weather. Stewart and Stokley in a ship at sea were able to observe the eclipse with a measured duration of 7 min. 6 sec., the longest period of totality in 1200 years.
We have discovered hard and soft X-ray emission from W Puppis, the last of the four classical AM Her stars to be detected in X-rays. The orbital light curves in both soft and hard X-rays are in excellent agreement with the mean optical light curve, indicating that essentially all of the accretion luminosity originates from a very small region at the white dwarf’s magnetic pole. An X-ray dip occurs once per binary period, when the magnetic pole lies closest to our line of sight, and is probably due to absorption. The X-ray data and optical spectroscopy constrain fairly well the geometry of the system, dictating an inclina-tion angle i < 70º and a mass for the white dwarf in excess of 1.1 Mʘ. X-ray and UV observations constrain the temperature of the soft X-ray component to lie in the range 20–45 eV, while the hard X-ray component has a temperature in excess of 6 keV. The observed flux of soft X-rays is much larger than that of hard X-rays. However, when the energy band-passes of the observations are taken into account, the ratio of the soft and hard X-ray luminosities Ls/Lh = 0.5-50. The ratio is unity for Tbb = 30 eV and Tbr = 50 keV; ifc is smaller if Tbb and/or Tbr are larger and is larger in the opposite case. These results, taken together with those for AM Her using the Einstein OGS, suggest that the famous “soft X-ray problem” in the AM Her stars may have gone away.
A characteristic feature of the plateau of Cambrian Limestone in the neighbourhood of Inchnadamff is the occurrence in it of swallow-holes, caves, and subterranean channels which are intimately associated with the geological history of the region. The valley of Allt nan Uamh (Burn of the Caves), locally known as the Coldstream Burn, furnishes striking examples of these phenomena. One of the caves in this valley yielded an interesting succession of deposits, from which were collected abundant remains of mammals and birds. The discovery of bones of the Northern Lynx, the Arctic Lemming, and the Northern Vole among these relics, and the collateral evidence of the materials forming some of these layers, seem to link the early history of this bone-cave with late glacial time, or at least with a period before the final disappearance of local glaciers in that region.
Lithium-air batteries have received extraordinary attention recently owing to their theoretical gravimetric energies being considerably higher than those of Li-ion batteries. There are, however, significant challenges to practical implementation, including low energy efficiency, cycle life, and power capability. These are due primarily to the lack of fundamental understanding of oxygen reduction and evolution reaction kinetics and parasitic reactions between oxygen redox intermediate species and nominally inactive battery components such as carbon in the oxygen electrode and electrolytes. In this article, we discuss recent advances in the mechanistic understanding of oxygen redox reactions in nonaqueous electrolytes and the search for electrolytes and electrode materials that are chemically stable in the oxygen electrode. In addition, methods to protect lithium metal against corrosion by water and dendrite formation in aqueous lithium-air batteries are discussed. Further materials innovations lie at the heart of research and development efforts that are needed to enable the development of lithium-oxygen batteries with enhanced round-trip efficiency and cycle life.
Local structural and metabolic as well as inter-regional connectivity abnormalities have been implicated in the neuropathology of major depressive disorder (MDD). How local tissue properties affect intrinsic functional connectivity is, however, unclear. Using a cross-sectional, multi-modal imaging approach, we investigated the relationship between local cortical tissue abnormalities and intrinsic resting-state functional connectivity (RSFC) in MDD.
A total of 20 MDD in-patients and 20 healthy controls underwent magnetic resonance imaging at 3 T for structural and functional imaging. Whole-brain cortical thickness was calculated and compared between groups. Regions with reduced cortical thickness defined seeds for subsequent whole-brain RSFC analyses. Contributions of structural tissue abnormalities on inter-regional RSFC were explicitly investigated.
Lower cortical thickness was observed in MDD in the right dorsomedial prefrontal cortex (PFC), superior temporal gyrus/temporal pole, middle-posterior cingulate cortex, and dorsolateral PFC. No differences in local fractional amplitude of low-frequency fluctuations were observed. Lower thickness in patients' dorsomedial PFC further directly and selectively affected its RSFC with the precuneus, which was unaffected by symptom severity. No effects of cortical thickness in other regions showing abnormal thickness were observed to influence functional connectivity.
Abnormal cortical thickness in the dorsomedial PFC in MDD patients was observed to selectively and directly affect its intrinsic connectivity with the precuneus in MDD patients independent of depression severity, thereby marking a potential vulnerability for maladaptive mood regulation. Future studies should include an unmedicated sample and replicate findings using independent component analysis to test for morphometric effects on network integrity.
The Canonbie Coalfield occupies a small tract of ground between the Liddel Water and the river Esk in the south-east part of the county of Dumfries. Though of limited extent, the coalfield has aroused considerable interest, due partly to the important series of plants obtained from the beds, and partly to the questions bearing on the correlation of the Carboniferous rocks of the Scottish Border with those in the North of England and Central Scotland.
Las Cumbres Observatory Global Telescope Network (LCOGT) is currently building a new kind of general-purpose astronomical facility: a fully robotic network of telescopes of 2m, 1m and 0.4m apertures and homogeneous instrumentation. A pan-network approach to scheduling (rather than per individual telescope) offers redundancy in the event of poor weather or technical failure, as well as the ability to observe a target around the clock. Here we describe the network design and instrumentation under development, together with the main science programmes already being lead by LCOGT staff.
This paper examines the variations in performance of amorphous silicon (a-Si:H) thin-film transistor (TFT) pixel driver circuits for active-matrix organic light-emitting diode (AMOLED) displays, which are subject to compressive or tensile mechanical strain. The external strain is induced by bending of the TFT substrate, and is measured by the observed changes in resistance of in-situ strain gauges. Mechanical strain impacts the performance of the circuit in terms of its drive current, which may be attributed to mobility and Fermi energy shifts in the individual TFTs. The effect of strain-induced shifts in the TFTs as a function of strain orientation (longitudinal or transverse) with respect to direction of current flow is also examined. Our measurements show that the variation in the drain current of a longitudinally oriented TFT can be as much as ∼ 1.5% for strains as high as 10−3. Proper layout and circuit design can suppress the effect of strain-induced shifts, and should be taken into consideration when designing stable TFT driver circuits for mechanically flexible AMOLED displays.
Development of a sensor capable of selective detection of specific nerve agents is imperative in today’s atmosphere of terrorism. The sensor needs to be inexpensive, portable, reliable, absent of false positives and available to all military and first responders. By utilizing the techniques of molecular imprinting, combinatorial chemistry, silica sol-gel synthesis and lanthanide luminescence, a sensor for the detection of the hydrolysis product of the nerve agent soman is being developed. There are many parameters that require investigation in order for the sensor to become a reality. These parameters include 1) the selection of a chelate that can bind to the lanthanide and anchor the nerve agent simulant during the formation of the molecularly imprinted polymer, 2) the determination of the environment best suited for this complex formation, 3) the formation, as well as modification of the silica sol-gel for molecular imprinting to take place, and 4) the proper quantity and ratios of monomers used to create the three dimensional imprint. Key to the success of optimizing these parameters is the development of a combinatorial assay that allows for the synthesis and testing of tens of thousands of combinations of parameters. Work on the development of the combinatorial assay has lead to a method of preparing thin film polymers capable of analyzing the presence of nerve agent simulants. Current work is underway to validate the combinatorial assay and to synthesize and evaluate a library of sensor materials selective for nerve agents.
Optical losses in thin film solar cells arise due to reflections at the top interfaces where dielectric discontinuities may be significant, e.g., between the glass and transparent conducting oxide (TCO) contact and between the TCO and semiconductor structure. Advanced optical engineering approaches are needed to minimize such losses. One approach is to incorporate multilayered or graded-index TCO films designed to act as broad-band anti-reflectors. Thus, it is important to be able to modulate the near-infrared/visible index of refraction of the TCO over a relatively wide range (e.g., 1.3 < n < 2.0) without increasing its extinction coefficient k or significantly degrading its electrical conductance. Here we report an investigation of SnO2 and ZnO sculptured thin films (STFs) under development for this purpose Sculptured thin films are deposited under low surface mobility conditions using stepwise or continuous variations in the polar and/or azimuthal angles of the deposition flux impinging on the surface. Deposition at a glancing polar angle leads to columnar growth, optical anisotropy, and low ordinary indices of refraction, whereas normal incidence deposition under the same conditions leads to dense isotropic films and high indices. In this study, we explore the dependence of the optical properties of SnO2 and ZnO, including index and birefringence spectra, on the polar deposition angle. Optical modeling reported here assesses the ability of the STF concept to provide tailored TCOs for advanced optical engineering of CdTe solar cell structures.
We present the science case for ICE-T, the International Concordia Explorer Telescope, a double telescope optimized for ultra-high and ultra wide field optical time-series photometry from
Dome C. ICE-T consists of two 60 cm 8°×8°-FOV Schmidt telescopes for Sloan g and i photometry and one independent 25 cm, solar, full-disk, Ca ii-K imaging
telescope on a single mount. ICE-T is therefore operable during night and day. A 28 cm narrow-field Maksutov spectrophotometric telescope for night-time aerosol measurements (TAVERN-SP) will be
provided by AWI early on and operated in parallel with IRAIT and later with ICE-T. The low scintillation noise and the long continuous darkness are among the unique properties for high
precision optical time-series photometry.