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Food group guideline adherence is vital to prevent obesity and diabetes. Various studies have demonstrated that environmental variables influence food intake behaviour. In the present study we examined the effect of a portion design plate with food group portion guidelines demarcated by coloured lines (ETE Plate™). A two-group quasi-experimental design was used to measure proportions of carbohydrate, vegetable and protein portions and user experience in a hospital staff lounge setting in Singapore. Lunch was served on the portion design plate before 12.15 hours. For comparison, a normal plate (without markings) was used after 12.15 hours. Changes in proportions of food groups from 2 months before the introduction of the design plate were analysed in a stratified sample at baseline (859 subjects, all on normal plates) to 1, 3 and 6 months after (in all 1016 subjects on the design plate, 968 subjects on the control plate). A total of 151 participants were asked about their experiences and opinions. Between-group comparisons were performed using t tests. Among those served on the portion design plate at 6 months after its introduction, the proportion of vegetables was 4·71 % (P < 0·001) higher and that of carbohydrates 2·83 % (P < 0·001) lower relative to the baseline. No significant change was found for proteins (−1·85 %). Over 6 months, we observed different change patterns between the different food group proportions. While participants were positive about the portion design plate, they did not think it would influence their personal behaviour. A portion design plate might stimulate food group guideline adherence among hospital staff and beyond.
The structure and kinematics of the broad line region in quasars are still unknown. One popular model is the disk-wind model that offers a geometric unification of a quasar based on the viewing angle. We construct a simple kinematical disk-wind model with a narrow outflowing wind angle. The model is combined with radiative transfer in the Sobolev, or high velocity, limit. We examine how angle of viewing affects the observed characteristics of the emission line. The line profiles were found to exhibit distinct properties depending on the orientation, wind opening angle, and region of the wind where the emission arises.
At low inclination angle (close to face-on), we find that the shape of the emission line is asymmetric, narrow, and significantly blueshifted. As the inclination angle increases (close to edge-on), the line profile becomes more symmetric, broader, and less blueshifted. Additionally, lines that arise close to the base of the disk wind, near the accretion disk, tend to be broad and symmetric. Single-peaked line profiles are recovered for the intermediate and equatorial wind. The model is also able to reproduce a faster response in either the red or blue sides of the line profile, consistent with reverberation mapping studies.
CCD images of quasars having redshifts between 0.3 and 0.65 are analyzed to study the association of galaxies with quasars. Average luminosity functions (LF) of the excess galaxies associated with the radio-loud quasars are determined. It is found that for the sub-sample with z>0.55, there is a significant brightening of the characteristic magnitude M*, if qo is assumed to be 0. Comparing computed quasar-galaxy spatial-covariance amplitudes, we can conclude, at the 0.025 significance level, that the spatial-covariance amplitudes of the sub-sample with z>0.55 are greater than those of the lower redshift quasars. This indicates that there has been a strong evolution of preferred sites for bright radio-loud quasars, implying some number-density evolution of quasars has taken place, and that some rich clusters at z∼0.6, in comparison with the local rich clusters, have significantly different physical conditions.
In taste cells, taste receptors, their coupled G proteins and downstream signalling elements mediate the detection and transduction of sweet, bitter and umami compounds. In some intestinal endocrine cells, taste receptors and gustducin contribute to the release of glucagon-like peptide 1 (GLP-1) and other gut hormones in response to glucose and non-energetic sweeteners. Conversely, taste cells have been found to express multiple hormones typically found in intestinal endocrine cells, e.g. GLP-1, glucagon, somatostatin and ghrelin. In the present study, by immunohistochemistry, multiple subsets of taste cells were found to express GLP-1. The release of GLP-1 from ‘endocrine taste cells’ into the bloodstream was examined. In wild-type mice, even after oesophagectomy and vagotomy, oral stimulation with glucose induced an elevation of GLP-1 levels in the bloodstream within 10 min. Stimulation of taste cell explants from wild-type mice with glucose led to the release of GLP-1 into the medium. Knocking out of the Tas1r3 gene did not eliminate glucose-stimulated GLP-1 release from taste cells in vivo. The present results indicate that a portion of the cephalic-phase rise in circulating GLP-1 levels is mediated by the direct release of GLP-1 from taste cells into the bloodstream.
In July 2011, a cluster of Yersinia enterocolitica infections was detected in southwestern Pennsylvania, USA. We investigated the outbreak's source and scope in order to prevent further transmission. Twenty-two persons were diagnosed with yersiniosis; 16 of whom reported consuming pasteurized dairy products from dairy A. Pasteurized milk and food samples were collected from this dairy. Y. enterocolitica was isolated from two products. Isolates from both food samples and available clinical isolates from nine dairy A consumers were indistinguishable by pulsed-field gel electrophoresis. Environmental and microbiological investigations were performed at dairy A and pasteurization deficiencies were noted. Because consumption of pasteurized milk is common and outbreaks have the potential to become large, public health interventions such as consumer advisories or closure of the dairy must be implemented quickly to prevent additional cases if epidemiological or laboratory evidence implicates pasteurized milk as the outbreak source.
Depth profiled positronium annihilation lifetime spectroscopy (PALS) has been used to probe the pore characteristics (size, distribution, and interconnectivity) in thin, porous films, including silica and organic-based films. The technique is sensitive to all pores (both interconnected and closed) in the size range from 0.3 nm to 300 nm, even in films buried under a diffusion barrier. PALS may be particularly useful in deducing the pore-size distribution in closed-pore systems where gas absorption methods are not available. In this technique a focussed beam of several keV positrons forms positronium (Ps, the electron-positron bound state) with a depth distribution that depends on the selected positron beam energy. Ps inherently localizes in the pores where its natural (vacuum) annihilation lifetime of 142 ns is reduced by collisions with the pore surfaces. The collisionally reduced Ps lifetime is correlated with pore size and is the key feature in transforming a Ps lifetime distribution into a pore size distribution. In thin silica films that have been made porous by a variety of methods the pores are found to be interconnected and an average pore size is determined. In a mesoporous methyl-silsesquioxane film with nominally closed pores a pore size distribution has been determined. The sensitivity of PALS to metal overlayer interdiffusion is demonstrated. PALS is a non-destructive, depth profiling technique with the only requirement that positrons can be implanted into the porous film where Ps can form.
The application of porous low-k interlayer dielectrics is needed for
reducing the parasitical capacitance, especially at 65-nm node and beyond.
The understanding of process-induced modifications to material properties is
crucial for a successful integration of these low-k dielectrics. The dry
etching processes of porous low-k materials are important modules in ULSI
fabrication. In this study, the interaction between MSQ-based JSR LKD-5109
films (shown by PALS to have interconnected 2.8 nm size pores) with
CF4/O2 plasma has been investigated. Various ratios of
O2 content were designed to characterize its effects on the
etch rate, formation of polymerization layer, and properties of the LKD-5109
film. Composition analysis was conducted by SIMS and FTIR. Moisture
absorption and fluorine diffusion into low-k films after etch process are
observed, along with carbon depletion near the surface region. The influence
of etching chemistries on the morphological characteristics of thin Ta
barrier layers (8-nm in thickness) deposited on etched low-k films were
further investigated by SEM, and it is found that oxygen concentration has
significant influences on the morphological characteristics of thin Ta
The recent renewal of interest in the time dependent response of complex material systems stems both from their increasing importance and from recent advances in theoretical tools and concepts. This paper describes one of these advances, the coupling model of relaxation. The coupling model proposes a view of how relaxation proceeds in time in which a primitive relaxation mode is coupled to its complex surroundings. Examples of the coupling model predictions for terminal relaxations, primary-segmental relaxations including physical aging, and secondary relaxations in polymers are described. It is able to confront and quantitatively explain several long-standing problems and anomalies for which traditional approaches, in their present form, such as distributions of relaxation times, free volume, configuration entropy and reptation are not successful. The coupling model response function is also appropriate for structural nonequilibrium and its predictions for volume recovery are described. The same coupling model response function is used as a timedependent kernal in a constitutive equation to discuss nonlinear viscoelasticity. The model incorporates the strain history dependence and allows for the evolution of material structure. Using information from strain-tickle experiments on polycarbonate and polyetherimide, we show that the coupling model reproduces the essential features observed experimentally for a variety of strain histories.
Glassy polycarbonate was subjected to cyclic stresses and the changes in its structure were studied by DSC, positronium annihilation lifetime spectroscopy (PALS), and small and medium angle X-ray scattering. Upon increased exposure to cyclic loading, the enthalpy overshoot near Tg increased in a manner similar to increasing physical aging. However, the “hole” size as revealed by PALS increased, unlike physical aging. SAXS reveals an increase in the short range order and the amplitude of density fluctuation. These results can be explained in a consistent manner. We conclude that mechanical loading does cause changes in the glassy structure.
As device dimensions continue to scale down into the deep submicrometer regime, there is an increasing challenge for fabricating robust gate dielectrics with low susceptibility to process-induced device degradation and a continuous motivation for the exploration of new options for thin gate dielectrics. This work assesses a variety of gate stack processing techniques as alternatives to conventionally furnace grown gate oxides in the context of a tenth-micron technology, which features LOCOS isolated, two-implant channel, NMOS transistors fabricated with a 3.0 nm thick gate dielectric, 0.15 μm thick polysilicon gate, implanted extension- and contact-junctions of 20 and 50 nm deep, respectively, and effective channel lengths down to 0.12 μm, operating at 1.2 volts. The alternative deposition and oxidation techniques include furnace oxynitride formation, rapid-thermal oxidation (RTO), rapid-thermal chemical vapor deposition (RTCVD) and plasma-assisted chemical vapor deposition (RPECVD). Compared to the 0.25- and 0.18-μm technological nodes, the thermal budgets associated with gate oxide formation are dramatically lower and their impact on channel dopant redistribution is not as strong as in previous technologies. Negligible polysilicon depletion effects were observed in the fabricated devices (Cinv/Cox = 97%). Drive currents and threshold voltage control comparable to furnace oxides were achieved by alternative gate-stack processing techniques.
The residual stress evolution in an epoxy during isothermal curing process has been determined experimentally. It was found that for a certain curing temperature range in which the characteristic time for the molecular motions leading to volume recovery is shorter than the time scale of the experiment, an incremental elastic constitutive equation can be used to describe the mechanical response of the epoxy. It was also found that appreciable residual stresses are developed in a threedimensionally constrained epoxy resin system within the rubbery state.
Octafunctionalized silsesquioxanes [(RsiO1.5)8, cubes] offer potential as rigid, hard nanoplatforms to which a variety of organofunctional groups can be appended. Crosslinking these groups leads to novel organic/inorganic nanocomposites that consist primarily of interfacial interactions. These materials can be 100% interphase. We present efforts to develop nanocomposite materials that consist of both continuous and discontinuous organic/inorganic phases. We then discuss methods of probing the properties of these materials.
We report the use of nickel-platinum silicide (NiPtSi) as a source/drain (S/D) material for strain engineering in P-MOSFETs to improve drive current performance. The material and electrical characteristics of NiPtSi with various Pt concentrations was investigated and compared with those of NiSi. Ni0.95Pt0.05Si was selected for device integration. A 0.18 μm gate length P-MOSFET achieved a 22% gain in IDsat when Ni0.95Pt0.05Si S/D is employed instead of NiSi S/D. The enhancement is attributed to strain modification effects related to the nickel-platinum silicidation process.
We use deep nIR imaging of 15 galaxy clusters at z ≃ 1 to study the build-up of the red-sequence in rich clusters since the Universe was half its present age. We measured, for the first time, the luminous-to-faint ratio of red-sequence galaxies at z=1 from a large ensemble of clusters, and found an increase of 100% in the ratio of luminous-to-faint red-sequence galaxies from z=0.45 to 1.0. The measured change in this ratio as function of redshift is well-reproduced by a simple evolutionary model developed in this work, that consists in an early truncation of the star formation for bright cluster galaxies and a delayed truncation for faint cluster galaxies.
Few studies have prospectively examined psychosocial and psychiatric
predictors of adolescent substance use disorders simultaneously.
To identify psychosocial and psychiatric predictors of substance use
disorders in adolescence.
School children aged 12 years (s. d. =0. 3) free from any substance use
disorder at grade7(n=428) were assessed in three
consecutive years, using a standardised psychiatric interview. Their
baseline psychosocial information was also collected. The outcome was the
onset age of a substance use disorder. The Cox regression model was used
for data analysis.
The most significant predictive factors for adolescent substance use
disorder included male gender, attention-deficit hyperactivity disorder,
conduct disorder and sibling use of tobacco. Three protective factors
against such morbidity included living in a household with two parents, a
good academic grade at grade 7 and objection to the use of
Early intervention for disruptive behaviour disorders and specific
psychosocial risk factors might prevent substance use disorders in early
Objectives: There has been a rapid growth in the use of patient-assessed outcomes (PAOs) that are measured in the assessment of health technologies. The process of collection of such measures can be costly, and there may be problems associated with the ability of the patient to complete them. The use of electronically stored routine data may reduce costs and overcome the problems associated with patient completion. The feasibility of using routine data surrogates for the UK Inflammatory Bowel Disease Questionnaire (UKIBDQ) and the Short Form 36 (SF-36) was examined.
Methods: Clinical terms and codes for the UKIBDQ and SF-36 questions were identified, and data from electronic routine sources were sought on patients participating in a randomized controlled trial. The presence or absence of relevant symptoms was used to generate surrogate scores, which were compared with the original scores.
Results: Most questions in the UKIBDQ and SF-36 were codable but only one third of the terms were recorded routinely in electronic form. The surrogate total IBDQ score had reasonable reliability (Kuder–Richardson coefficient = 0.51), but this reliability could not be determined for the SF-36. Intraclass correlations between routine and designed data were poor to weak.
Conclusions: Although electronic routine data sources had the capacity to develop surrogate measures for patient assessed outcomes, there was evidence of wide underutilization of coding systems leading to an underreporting of symptoms. This finding is consistent with previous literature where only poor correlations were illustrated between patient assessed outcomes and surrogate scoring of symptoms.
Third-generation rediae and escaped cercariae of Philophthalmus gralli are found primarily in the interacinar spaces on the periphery of the hepatopancreas of its molluscan host, Tarebia granifera. The presence of these stages of P. gralli causes both mechanical and physiological damage to the adjacent host cells. Mechanical damage results from ingestion by rediae and pressure exerted by motile rediae and cercariae. Histochemical tests involving two different substrates L-leucyl-α-naphthylamide and L-leucyl-4-methoxy-β-naphthylamide, have revealed the occurrence of aminopeptidase activity associated with the body surfaces of both rediae and cercariae. This exopeptidase is believed to be responsible for the lysis of the cytoplasm of surrounding host cells during migration and to be associated with extracaecal digestion. The intensity of the enzyme activity is correlated with the ages of the rediae and cercariae. Young rediae did not reveal aminopeptidase activity and cercariae within redial brood chambers revealed little or no activity.
This research was supported in part by a grant from the American Cancer Society.
Sevin (1-naphthyl N-methylcarbamate) was first shown to have miticidal properties in 1957 when Allen et al. (1) found that it was moderately effective for the control oi the cyclamen mite, Steneotarsonmus pallidus (Banks), on strawberries. Subsequently it was demonstrated that Sevin would control the northern fowl mite, Ornithonyssus sylviarum (C. and F.) (7, 8, 9), suppress the brown mite, Bryobia arborea M. and A. (18), and the peach silver mite, Vasates cornutus (Banks) (18), and practically eliminate the predacious mite, Typhlodromus rhenanus Oudms. (18). It is not toxic to the European red mite, Panonychus ulmi (Koch) (18), the desert spider mite, Tetranychus desertorum Banks (4), and the two-spotted spider mite, Tetranychus telarius (L.) (6, 15); usually the use of Sevin for insect control will increase the numbers of these mites, and in this respect its effect is similar to that of DDT.
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