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To characterize contacts in general wards, a prospective survey of healthcare workers (HCWs), patients and visitors was conducted using self-reported diary, direct observation and telephone interviews. Nurses, doctors and assorted HCWs reported a median of 14, 18 and 15 contact persons over one work shift, respectively. Within 1 h, we observed 3·5 episodes with 25·6 min of cumulative contact time for nurses, 2·9 episodes and 22·1 min for doctors and 5·0 episodes with 44·3 min for assorted-HCWs. In interactions with patients, nurses had multiple brief episodes of contact; doctors had fewer episodes and less cumulative contact time; assorted-HCWs had fewer contact episodes of longer durations (than for nurses and doctors). Assortative mixing occurred amongst HCWs: those of the same HCW type were the next most frequent class of contact after patients. Over 24-h, patients contacted 14 persons with 23 episodes and 314·5 min of contact time. Patient-to-patient contact episodes were rare, but a maximum of five were documented from one patient participant. 22·9% of visitors reported contact with patients other than the one they visited. Our study revealed differences in the characteristics of contacts among different HCW types and potential transmission routes from patients to others within the ward environment.
Some preliminary experimental results are presented, which characterize the behaviour of small-scale artificial avalanches. The laboratory simulation consisted of releasing a finite mass of non-cohesive granular material to flow without restriction down an inclined surface which includes a curved part at the base where the run-out zone is encountered. Three contrasting materials, of 3 mm and 5 mm diameter size sortings, and also two different bed roughnesses were used.
Results indicate that a theoretical model which presumes a flow-regime-type avalanche may be too restrictive, in the sense that it describes a limiting case which does not often occur even under controlled conditions. Some suggestions are made for amendments to current theoretical concepts.
Since the emergence of Middle East respiratory syndrome coronavirus (MERS-CoV), Singapore has enhanced its national surveillance system to detect the potential importation of this novel pathogen. Using the guidelines from the Singapore Ministry of Health, a suspect case was defined as a person with clinical signs and symptoms suggestive of pneumonia or severe respiratory infection with breathlessness, and with an epidemiological link to countries where MERS-CoV cases had been reported within the preceding 14 days. This report describes a retrospective review of 851 suspected MERS-CoV cases assessed at the adult tertiary-care hospital in Singapore between September 2012 and December 2015. In total, 262 patients (31%) were hospitalized. All had MERS-CoV infection ruled out by RT–PCR or clinical assessment. Two hundred and thirty (88%) of the hospitalized patients were also investigated for influenza virus by RT–PCR. Of these, 62 (27%) tested positive for seasonal influenza. None of the patients with positive influenza results had been vaccinated in the year prior to hospital admission. Ninety-three (36%) out of the 262 hospitalized patients had clinical and/or radiological evidence of pneumonia. This study demonstrates the potential benefits of pre-travel vaccination against influenza and pneumococcal disease.
Collisional excitation of autoionizing levels is found to contribute significantly to the ionization rate for certain ions at temperatures characteristic of the solar corona. Preliminary calculations have been carried out for O IV, O V, O VI, Fe XV and Fe XVI. Autoionization may be of importance for O IV and increases by approximately a factor of two the ionization rate of Fe XV and XVI.
The physico-chemical and interfacial properties of fat emulsions influence lipid digestion and may affect postprandial responses. The aim of the present study was to determine the effects of the modification of the interfacial layer of a fat emulsion by cross-linking on postprandial metabolic and appetite responses. A total of fifteen healthy individuals (26·5 (sem 6·9) years and BMI 21·9 (sem 2·0) kg/m2) participated in a cross-over design experiment in which they consumed two isoenergetic (1924 kJ (460 kcal)) and isovolumic (250 g) emulsions stabilised with either sodium caseinate (Cas) or transglutaminase-cross-linked sodium caseinate (Cas-TG) in a randomised order. Blood samples were collected from the individuals at baseline and for 6 h postprandially for the determination of serum TAG and plasma NEFA, cholecystokinin (CCK), glucagon-like peptide 1 (GLP-1), glucose and insulin responses. Appetite was assessed using visual analogue scales. Postprandial TAG and NEFA responses and gastric emptying (GE) rates were comparable between the emulsions. CCK increased more after the ingestion of Cas-TG than after the ingestion of Cas (P< 0·05), while GLP-1 responses did not differ between the two test emulsions. Glucose and insulin profiles were lower after consuming Cas-TG than after consuming Cas (P< 0·05). The overall insulin, glucose and CCK responses, expressed as areas above/under the curve, did not differ significantly between the Cas and Cas-TG meal conditions. Satiety ratings were reduced and hunger, desire to eat and thirst ratings increased more after the ingestion of Cas-TG than after the ingestion of Cas (P< 0·05). The present results suggest that even a subtle structural modification of the interfacial layer of a fat emulsion can alter the early postprandial profiles of glucose, insulin, CCK, appetite and satiety through decreased protein digestion without affecting significantly on GE or overall lipid digestion.
In this contribution, we report the synthesis and characterization of NixFe3-xO4 and CoxFe3-xO4 redox nanomaterials using sol-gel method. These materials will be used to produce solar fuels such as H2 or syngas from H2O and/or CO2 via solar thermochemical cycles (STCs). For the sol-gel synthesis of ferrites, the Ni, Co, Fe precursor salts were dissolved in ethanol and propylene oxide (PO) was added dropwise to the well mixed solution as a gelation agent to achieve gel formation. Freshly synthesized gels were aged, dried, and calcined by heating them to 600°C in air. The calcined powders were characterized by powder x-ray diffractometer (XRD), BET surface area, as well as scanning (SEM) and transmission (TEM) electron microscopy. Their suitability to be used in STCs for the production of solar fuels was assessed by performing several reduction/re-oxidation cycles using a thermogravimetric analyzer (TGA).
This study aims to examine Queensland suicide trends in the Australian-born population and in the overseas-born populations over the past 2 decades.
All suicide cases for the period 1991–2009 were identified in the Queensland Suicide Register. Age-standardised suicide rates were calculated. Joinpoint regression and Poisson regression were applied.
A significant decline in suicide rates of young (15–44 years) overseas-born males was reported over the past 2 decades. Australian-born young males showed significant increase until 1996, followed by a significant decline; furthermore, their suicide rates were significantly higher when compared to overseas-born (RR = 1.36, 95%CI: 1.15; 1.62). Contrary older Australian-born males (45+ years) had significantly lower suicide rates than overseas-born males (RR = 0.90, 95%CI: 0.83; 0.98). Despite the convergence of the suicide trends for older males, changes were not significant. While Australian-born females had a significant increase in suicides, overseas-born females had a decline in 1991–2009.
Conclusion. Significantly declining suicide rates of migrants have contributed to the declining in suicide trends in Queensland. Potential reasons for significantly lower suicide rates among young migrants might include the change in the nature of migration from involuntary to voluntary.
This research includes results on the corrosion performance of reinforcing steel in cement-based mortar (pH ~ 13) when cactus (Opuntia Ficus Indica –Nopal) slime was used as an addition. The cactus slime addition was mixed at different concentrations by mixing water mass (0%, 1.5%, 4%, 8%, 42%, and 95%). Half-cell potentials and LPR measurements were performed at different time periods to characterize the possible corrosion inhibiting effect of the cactus additions tested. Results showed good corrosion inhibiting effect of Nopal slime on reinforcing steel, in all tested solutions, when chloride ions were present. The addition of such cactus led to an apparent formation of a denser and more packed oxide/hydroxide surface layer on the steel surface that decreased corrosion activity. This oxide/hydroxide layer growth was confirmed from microscopic evaluation of the metal surface layer performed at the end of the research program. The preliminary findings suggest that adding Nopal slime in concentrations between 4% and 8%, by water mass, might be suitable for durability enhancing applications in cement-based mortar.
Strong blue, red and near-infrared photoluminescence has been observed from Si+-implanted and pulse-annealed SiO2 layers. Raman scattering and high-resolution electron microscopy analyses have revealed a correlation between the structure of the Si inclusions in the SiO2 matrix and the photoluminescence. Structural transformations in the Si-rich SiO2 layers during pulse and furnace annealing have been discussed in terms of the changes in the light emission observed experimentally. Small Si clusters, non-crystalline inclusions and nanocrystals are believed to be the light sources. The blue, red and near-infrared photoluminescence is associated with small complexes of excess Si atoms, non-crystalline Si nanoinclusions and quantum-confined Si nanocrystals, respectively.
We consider the impact of taxes on the quantity and quality produced by a competitive firm of goods, such as wine, for which market value accrues with age. Our analysis found the following: an increase in the volumetric retail tax collected at sale increases quality, so that the basic Alchian-Allen effect holds. However, an increase in the volumetric storage tax collected each period decreases quality, as does an increase in the ad valorem storage tax. The effect of an increase in the ad valorem retail tax on quality is indeterminate. Increases in any of the four taxes reduce the quantity of wine produced. Any two-tax system that includes a volumetric sales tax spans the full range of feasible tax revenues with positive tax rates. For any tax system that reduces quality relative to the firm's no-tax equilibrium, there is another tax system that increases tax revenues, eliminates the quality distortion, and does not increase the quantity distortion. Many wine industry observers believe that most, if not all, existing tax systems tend to result in the suboptimal provision of quality. Our results suggest that the wide variety of wine tax systems is not prima facie evidence that these systems, or most of them, are inefficient. Provided the system includes a volumetric sales tax it may be efficient, regardless of which of the other instruments, or how many of them, are used. Assertions regarding inefficiency must be evaluated on an empirical case-by-case basis. Our analysis provides a theoretical framework for such research. (JEL Classification: D2, H2, Q1)
Physico-chemical and textural properties of foods in addition to their chemical composition modify postprandial metabolism and signals from the gastrointestinal tract. Enzymatic cross-linking of protein is a tool to modify food texture and structure without changing nutritional composition. We investigated the effects of structure modification of a milk protein-based model food and the type of milk protein used on postprandial hormonal, metabolic and appetitive responses. Healthy males (n 8) consumed an isoenergetic and isovolumic test product containing either whey protein (Wh, low-viscous liquid), casein (Cas, high-viscous liquid) or Cas protein cross-linked with transglutaminase (Cas-TG, rigid gel) in a randomised order. Blood samples were drawn for plasma glucose, insulin, cholecystokinin (CCK), glucagon-like peptide 1 and peptide YY analysis for 4 h. Appetite was assessed at concomitant time points. Cas and Wh were more potent in lowering postprandial glucose than Cas-TG during the first hour. Insulin concentrations peaked at 30 min, but the peaks were more pronounced for Cas and Wh than for Cas-TG. The increase in CCK was similar for Cas and Wh in the first 15 min, whereas for Cas-TG, the CCK release was significantly lower, but more sustained. The feeling of fullness was stronger after the consumption of Cas-TG than after the consumption of Cas and Wh. The present results suggest that food structure is more effective in modulating the postprandial responses than the type of dairy protein used. Modification of protein-based food structure could thus offer a possible tool for lowering postprandial glucose and insulin concentrations and enhancing postprandial fullness.
Bulk aluminum nitride boules have been grown at driving rates of 0.9mm/h by the self-seeded sublimation-recondensation technique. Up to 15mm diameter substrates cut from those boules present large single crystal grains that have been analyzed using different techniques. X-ray double crystal diffraction shows a full-width-at-half-maximum of around 100 arcsec and X-ray topography reveals extensive areas with a density of dislocations less than 104 cm−2. These substrates have been prepared by chemical mechanical polishing techniques to obtain a surface roughness of 1.4-1.6nm.
We developed GaAs heteroepitaxy on a Si substrate by metalorganio vapor phase epitaxy (MOVPE) using tertiarybutylarsine (TBAs). When we preheated Si at 1000ºC in the atmosphere including TBAs, a carbide layer was formed on the Si surface. This led to polycrystalline GaAs growth. By carrying out high-temperature preheating in an H2 -only atmosphere and supplying TBAs after the preheating, we have successfully grown single-crystal GaAs with a mirror surface in a process completely free of AsH3.
Using surface second harmonic generation (SSHG) at 1053nm, we study the influence of off-axis orientation and surface structure of silicon (111) surfaces. We study wafers cut at angles between 0° and 5° in the  direction. The surface structure is varied by thermal oxidation at 850°C, annealing, and thinning the oxide in a HF solution. For comparison, nitride films are also investigated. The characteristic rotational symmetry of the SSHG-signal for (111) flat (non-vicinal) surfaces is enhanced by a Si/SiO2 interface. The oxide layer also influences the signals due to the steps on vicinal surfaces. The results are discussed in comparison with a microscopic model of the oxidized misoriented surface.