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To assess the extent of error present in self-reported weight data in the Women’s Health Initiative, variables that may be associated with error, and to develop methods to reduce any identified error.
Prospective cohort study.
Forty clinical centres in the USA.
Women (n 75 336) participating in the Women’s Health Initiative Observational Study (WHI-OS) and women (n 6236) participating in the WHI Long Life Study (LLS) with self-reported and measured weight collected about 20 years later (2013–2014).
The correlation between self-reported and measured weights was 0·97. On average, women under-reported their weight by about 2 lb (0·91 kg). The discrepancies varied by age, race/ethnicity, education and BMI. Compared with normal-weight women, underweight women over-reported their weight by 3·86 lb (1·75 kg) and obese women under-reported their weight by 4·18 lb (1·90 kg) on average. The higher the degree of excess weight, the greater the under-reporting of weight. Adjusting self-reported weight for an individual’s age, race/ethnicity and education yielded an identical average weight to that measured.
Correlations between self-reported and measured weights in the WHI are high. Discrepancies varied by different sociodemographic characteristics, especially an individual’s BMI. Correction of self-reported weight for individual characteristics could improve the accuracy of assessment of obesity status in postmenopausal women.
In the semi-arid parts of west Asia and north Africa, barley straw (Hordeum vulgareL. subsp. vulgare)and cereal stubbles provide between one-quarter and one-half of the metabolizable energy (ME) offered to sheep. In barley straw, voluntary straw dry-matter (DM) intake (VSI) is a good predictor of body weight gain (R2 = 0.85; data of Capper et al., 1989). This varies according to location and year (CV = 0.30 to 0.40) and varies genetically, with an average genotypic CV of 0.07, which can exceed 0.10 in wet years. Genotype X environment interactions in VSI are important (Table 1).
A genetically high VSI is advantageous in cool, wet, favourable growing conditions, when VSI is normally low. In drought conditions, VSI is high, genetically varies relatively little (Table 1) and is less important for the farmer than straw and grain yields. Barley breeders working in drought-prone environments prefer to do most of their selection for yield in dry conditions (Ceccarelli, 1993). Breeders are increasingly selecting for high VSI but wish to focus their testing plots in dry areas. Therefore they need indirect tests that indicate the nutritive value of straw when it is grown in wet environments.
Throughout the history of the Fatimid empire (909–1176/296–566), Byzantine sources support the idea that contact was kept to a minimum for trade. However, Arab historians reveal that in fact al-Mustansir engaged in correspondence, gift exchanges and embassies with several emperors. Descriptions of these mutual relations in the reign of al-Mustansir are a political mirror to the international effects of events such as the arrival of the Seljuk Turks, uprisings and civil war, and are also a fascinating insight into the diplomacy of Muslims and Christians banding together at a time of significant crisis for both.
Variation in human cognitive ability is of consequence to a large number of health and social outcomes and is substantially heritable. Genetic linkage, genome-wide association, and copy number variant studies have investigated the contribution of genetic variation to individual differences in normal cognitive ability, but little research has considered the role of rare genetic variants. Exome sequencing studies have already met with success in discovering novel trait-gene associations for other complex traits. Here, we use exome sequencing to investigate the effects of rare variants on general cognitive ability. Unrelated Scottish individuals were selected for high scores on a general component of intelligence (g). The frequency of rare genetic variants (in n = 146) was compared with those from Scottish controls (total n = 486) who scored in the lower to middle range of the g distribution or on a proxy measure of g. Biological pathway analysis highlighted enrichment of the mitochondrial inner membrane component and apical part of cell gene ontology terms. Global burden analysis showed a greater total number of rare variants carried by high g cases versus controls, which is inconsistent with a mutation load hypothesis whereby mutations negatively affect g. The general finding of greater non-synonymous (vs. synonymous) variant effects is in line with evolutionary hypotheses for g. Given that this first sequencing study of high g was small, promising results were found, suggesting that the study of rare variants in larger samples would be worthwhile.
M. fortuitum is a rapidly growing mycobacterium associated with community-acquired and nosocomial wound, soft tissue, and pulmonary infections. It has been postulated that water has been the source of infection especially in the hospital setting. The aim of this study was to determine if municipal water may be the source of community-acquired or nosocomial infections in the Brisbane area. Between 2007 and 2009, 20 strains of M. fortuitum were recovered from municipal water and 53 patients’ isolates were submitted to the reference laboratory. A wide variation in strain types was identified using repetitive element sequence-based PCR, with 13 clusters of ⩾2 indistinguishable isolates, and 28 patterns consisting of individual isolates. The clusters could be grouped into seven similar groups (>95% similarity). Municipal water and clinical isolates collected during the same time period and from the same geographical area consisted of different strain types, making municipal water an unlikely source of sporadic human infection.
Discrete and coalesced monocrystalline layers of lateral- and pendeo-epitaxially grown GaN and AlxGal−xN layers originating from GaN stripes deposited within windows contained in SiO2 masks or from side walls of GaN seed structures containing SiNx top masks have been grown via organometallic vapor phase deposition on GaN/AlN/6H-SiC(0001) substrates. Multilayer heterostructures of GaN and AlxGal−N were also achieved. Scanning and transmission electron microscopies and atomic force microscopy were used to evaluate the microstructures, the type and distribution of dislocations and the surface roughness of the resulting films. The extent and microstructural characteristics of the laterally overgrown GaN regions were a strong function of stripe orientation and temperature. These regions contained a low density of dislocations. The RMS roughness of the (1120) sidewall plane of the pendeoepitaxial structures was approximately 0.100 nm.
Epitaxially grown GaN by metal organic chemical vapor deposition (MOCVD) on SiC were implanted with 100 keV Si+ (for n-type) and 80 keV Mg+ (for p-type) with various fluences from 1×1012 to 7×1015 ions/cm2 at liquid nitrogen temperature (LT), room temperature (RT), and 700 °C (HT). High temperature (1200 °C and 1500 °C) annealing was carried out after capping the GaN with epitaxial AIN by MOCVD to study damage recovery. Samples were capped by a layer of AIN in order to protect the GaN surface during annealing. Effects of implant temperature, damage and dopant activation are critically studied to evaluate a role of ion implantation in doping of GaN. The damage was studied by Rutherford Backscattering/Channeling, spectroscopic ellipsometry and photoluminescence. Results show dependence of radiation damage level on temperature of the substrate during implantation: implantations at elevated temperatures up to 550 °C decrease the lattice disorder; “hot implants” above 550 °C can not be useful in doping of GaN due to nitrogen loss from the surface. SE measurements have indicated very high sensitivity to the implantation damage. PL measurements at LT of 80 keV Mg+ (5×1014 cm-2) implanted and annealed GaN showed two peaks : one ∼100 meV and another ∼140 meV away from the band edge.
In situ cleaning of MOCVD-grown GaN/AlN/6H-SiC substrates using NH3-seeded supersonic molecular beams was investigated. Removal of surface carbon and oxygen contaminants was achieved by heating at 730°C under a hyperthermal NH 3 beam. Oxygen is removed primarily by thermal desorption; however, carbon removal requires an NH3 flux. Atomically smooth surfaces with regular steps are obtained after NH3 beam cleaning. Homoepitaxial growth of smooth, highly textured GaN films was accomplished at 700°C by employing a 0.61-eV NH3 beam and an effusive Ga source.
Pendeo-epitaxial lateral growth (PE) of GaN epilayers on (0001) 6H-silicon carbide and (011) Si substrates has been achieved. Growth on the latter substrate was accomplished through the use of a 3C-SiC transition layer. The coalesced PE GaN epilayers were characterized using scanning electron diffraction, x-ray diffraction and photoluminescence spectroscopy. The regions of lateral growth exhibited ∼0.2° crystallographic tilt relative to the seed layer. The GaN seed and PE epilayers grown on the 3C-SiC/Si substrates exhibited comparable optical characteristics to the GaN seed and PE grown on 6H-SiC substrates. The near band-edge emission of the GaN/3C-SiC/Si seed was 3.450 eV (FWHM ∼ 19 meV) and the GaN/6H-SiC seed was 3.466 eV (FWHM ∼ 4 meV).
We have studied the formation of titanium silicides in the presence of an ultra-thin layer of Ta, interposed between Ti and Si. In-situ x-ray diffraction (XRD), resistance measurements and elastic light scattering were used to study the thin film reactions in real time during ramp anneals to 1000°C. On poly-Si substrates the Ta thickness was varied from 0 to 1.5 nm while the Ti thickness was held constant at ∼27 nm. The time-resolved XRD shows that the volume fraction of C40 and metal-rich silicide phases grows with increasing Ta layer thickness. Increased Ta layer thicknesses also delay the growth of the C49 disilicide phase to higher temperatures. Among the Ta thicknesses we examined, 0.3 nm is the most effective in lowering the C49-C54 transformation temperature. Films with Ta layers thicker than 0.5 nm do not completely transform into the C54 phase. The texture of the C54 phase is also sensitive to the Ta thickness. The C54 disilicide film is predominantly (010) textured for the Ti / 0.3 nm Ta sample. The final C54 texture is significantly different for Ta layers thinner or thicker than the optimal 0.3 nm. This suggests that the most effective thickness for lowering the C54 formation temperature is related to the development of a strong (010) texture. The possibility of a template effect by the C40 or metal-rich Ti5Si3 phases is also discussed on the basis of texture considerations.
Dideoxy nucleotide sequencing of a portion of the 1D gene of SAT-type foot-and-mouth disease viruses (FMDV) was used to derive phylogenetic relationships between viruses recovered from the oesophageo-pharyngeal secretions of buffalo in the Kruger National Park as well as several other wildlife areas in southern Africa. The three serotypes differed from one another by more than 40 % while intratypic variation did not exceed 29%. Within each type, isolates from particular countries were more closely related to one another than to isolates from other countries lending credence to previous observations that FMDV evolve independently in different regions of the subcontinent.
Objectives: To assess the volume and range of diagnosis in new patients referred to paediatric cardiac outpatient clinics. Methods: Data was collected prospectively, using a proforma completed at all outpatient clinics over a period of three months. Results: There were 526 new referrals, representing an increase of almost one-fifth compared to 5 years ago. Of the referrals, 78 percent came from hospital doctors, and 22 percent from general practitioners, with 221 of those referred being infants. A heart murmur was the most common reason for referral, representing almost two-thirds of cases. In 372 patients referred (71 percent), the heart was discovered to be structurally normal. The proportion of patients with normal hearts referred by general practitioners and hospital doctors were 81 percent, and 68 percent, respectively (p less than 0.004). There was considerable variation in the pattern of referral between doctors working in different hospitals. Conclusion: New referrals to centres dealing with congenital cardiac malformations are increasing alarmingly, with the majority of the children referred having normal hearts. This increase in demand for specialist services has important implications for resources and training.
Purpose: Having previously reviewed the implementation of systematic in vivo dosimetry at the Norfolk and Norwich Hospital this paper examines the results of entrance dose measurements for specific sites/techniques and determines whether different action/alert protocols are required for these different categories.
Methods and materials: Entrance dose measurements using p-type diodes were analysed for the following treatment categories: Breast, head and neck in beam direction shell, abdomino-pelvic and intrathoracic. A 4% tolerance was applied.
Results: Mean deviations from expected dose and proportion of measurements exceeding tolerance were: Breast: +1.15%±3.04% (1SD), 238/1073≥4%; Head and neck: +0.35%±2.20% (1SD), 21/326≥4%; Abdomino-pelvic: +0.52%±2.75% (1SD), 93/712≥4%; Intrathoracic: −0.01%±2.75% (1SD), 22/119≥4%. Significant improvements in results for breast patients were noted following the introduction of a commercial breast board. The results for abdomino-pelvic patients confirmed a substantial variation in diode response under short FSD, wedged fields at 16MV (that had not been corrected for). The statistical uncertainty in dose measurement for each treatment category was calculated in order to assist determination of appropriate tolerance levels.
Conclusions: A blanket tolerance of 4% was generally too low given the extent of measurement uncertainty. The relatively high number of readings outside tolerance where identification of errors was difficult/impossible resulted in inconsistent application of the action protocol. Some widening of tolerances is likely to improve quality of procedure and treatment. Appropriate action levels are recommended for each treatment category.
The changes taking place in the mixed farming systems of northwest Syria were examined by re-visiting, in 1996 and 2000, five villages along a rainfall gradient. The villages had been surveyed first in 1977–79. In those villages with moderate rainfall, intensification of crop production, namely a trend towards cereal monoculture and the planting of tree crops, did not lead to specialization in cropping at the expense of sheep ownership. In contrast, households in the areas too dry for most rainfed crops except barley (Hordeum vulgare) were more likely to sell their sheep because they depended heavily on off-farm income. Increases in crop yields were found but these only benefited the families in villages in the higher rainfall zones. Conversely, with the exception of ewe fertility, there was little evidence of improvements in sheep productivity. The mixed farming systems in the five villages sampled are still passing through a period of transition, and the cropping component will undoubtedly continue to change. This is less likely to happen to the small ruminant component in the near future unless the sector is given higher priority in national policy. As a strategy to increase feed production and balance the crop rotations, the prospects for closer crop/livestock integration at the farm level are limited by the many difficulties associated with the introduction of leguminous pasture and forage crops.
An identifying characteristic of Staphylococcus aureus is the production of staphylocoagulase (coagulase). The aim of this study was to determine the clonal distribution of coagulase gene (coa) variants within populations of S. aureus defined by multilocus sequence typing (MLST), pulsed-field gel electrophoresis (PFGE), and protein A variation. The N-terminal region of the coa gene from 43 methicillin-susceptible (MSSA) and 252 methicillin-resistant (MRSA) S. aureus human isolates and 9 animal S. aureus isolates was amplified and digested with HinfI. Twelve types were identified amongst the MSSA isolates and the majority (93%) of MRSA isolates were assigned to 5 of the 12 types. MLST and PFGE analysis identified epidemic populations of MRSA and each epidemic population was characterized by a different coagulase type. Nine of the 12 MLST-defined clonal complex ancestral genotypes recently described each carried a different coagulase type suggesting that coagulase evolution and the evolution of the clonal complexes are intimately related.
A study was designed to investigate management factors that might influence the shedding of verocytotoxin-producing Escherichia coli (VTEC) O157 by beef cows in Scotland, where there is a particularly high rate of human infection. Thirty-two herds were visited at least monthly over approximately 1 year for collection of fresh faecal pat samples and information on management factors. The faecal pat samples were tested for VTEC O157 by established culture and immunomagnetic separation methods. Questionnaires were completed at the monthly visits to record management factors. Data were analysed using both univariate and multi-factor (GLMM) analysis. Changes in the number of cows in a group, dogs, wild geese, housing, and the feeding of draff (distillers' grains) were statistically significant as risk factors. The event of calving appeared to reduce the likelihood of shedding. Any effects of weaning or turnout were not statistically significant. It appears that the rate of shedding of VTEC O157 is influenced by several factors but possibly the most important of these are the circumstances of animals being housed, or, when outside, the presence of wild geese.