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It has not been well established whether dietary folate intake reduces the risk of diabetes development. We aimed to clarify the prospective association between dietary folate intake and type 2 diabetes (T2D) risk among 7333 Korean adults aged 40 years or older who were included in the Multi-Rural Communities Cohort. Dietary folate intake was estimated from all 106 food items listed on a FFQ, not including folate intake from supplements. Two different measurements of dietary folate intake were used: the baseline consumption and the average consumption from baseline until just before the end of follow-up. The association between folate intake and T2D risk was determined through a modified Poisson regression model with a robust error estimator controlling for potential confounders. For 29 745 person years, 319 cases of diabetes were ascertained. In multivariable analyses, dietary folate intake was inversely associated with risk of T2D for women, not for men. For women, the incidence rate ratio of diabetes in the third tertile compared with the first tertile was 0·57 (95 % CI 0·38–0·87, Pfor trend=0·0085) in the baseline consumption model and 0·64 (95 % CI 0·43–0·95, Pfor trend=0·0244) in the average consumption model. These inverse associations was found in both normal fasting blood glucose group and impaired fasting glucose group among women. Among non-users of multinutrients and vitamin supplements, the significant inverse association remained. Thus, higher dietary intake of folate is prospectively associated with lower risk of diabetes for women.
Hydrogels are considered smart materials because they respond to environmental stimuli. Sensors that monitor the body’s pH levels would be helpful for doctors to determine the severity of a patient’s condition, especially if they exhibit signs of shock. The motivation of this project is to create a biomedical device that can be worn sublingually or implanted into the body to help doctors with diagnosing a patient’s condition. The magnitude of the swelling/deswelling behavior can be measured by placing a sample of the hydrogel in a piezoresistive sensor. The degree of swelling/deswelling is directly proportional to the change in pH of the aqueous solution it is placed in. In this study, a variety of compositions of pH responsive hydrogels were designed and tested to determine the response time and magnitude for use in both macro and micro sensor arrays. This pressure sensor has been designed for use with thinner gels than have been used in the past. The results for swelling time and magnitude were compared to determine the effect of the thickness of the hydrogel samples on the swelling/deswelling kinetics of the material in order to find the appropriate composition, thickness and device that will yield the desired response rate and sensitivity.
WO3 doped TiO2 nanotube(WO3-doped TNT) thin film was fabricated by anodizing the TiO2 nanotube (TNT) film in an NH4F electrolyte containing WO4- ions. The sample was characterized by Field Emission Scanning Electron Microscopy (FE-SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and UV–Vis diffuse reflectance spectroscopy (DRS). The results show that WO3 was successfully doped into TiO2 nanotubes and the absorption edge of WO3 doped TNT appeared to be red shifted. The photoelectrocatalytic (PEC) activity of WO3 doped TNT electrode was evaluated through the PEC degradation of aqueous Acid Blue 80. The experimental results demonstrated that the PEC degradation rate of WO3 doped TNT is increased by 48% and by 167% over that of non-doped TNT under UVA light irradiation and visible-light irradiation, respectively, at an applied potential of 1.54V. The degradation rates of WO3 doped TNT under photocatalytic (PC), electrochemical (EC), and PEC processes were compared. The results reveal the synergetic effect of PC and EC processes.
In this study we estimate the frequency at which P-element insertion events, as identified by in situ hybridization, generate lethal and mild viability mutations. The frequency of lethal mutations generated per insertion event was 0·004. Viability dropped an average of 1% per insertion event. Our results indicate that it is deletions and rearrangements resulting from the mobilization of P elements already in place and not the insertions per se that cause the drastic effects on viability and fitness observed in most studies of P–M dysgenesis-derived mutations. Elements of five other families (I, copia, 412, B104, and gypsy) were not mobilized in these crosses. Finally, we contrast the density of P elements on the X chromosome with the density on the four autosomal arms in a collection of thirty genomes from an African population. The relative number of P elements on the X chromosome is too high to be explained by either a hemizygous selection or a neutrality model. The possible reasons for the failure to detect selection are discussed.
At plasma densities lower than about 1018 cm-3, strictly speaking, the LTE model cannot be used when the electron temperature is calculated from measured spectral line intensity ratios. In this work a number of nitrogen spectral lines were studied at an electron density of about 1016 cm-3, and the results are discussed with reference to the LTE and semi-coronal models. A method is suggested for analyzing line intensity ratio data from plasmas in the semi-coronal regime.
Over the last 30 years it has become apparent that specific dietary fatty acids are capable of regulating, either directly or indirectly through various signal pathways, the expression of numerous genes, either positively or negatively. Such nutrient-gene interactions have important effects on cell metabolism, differentiation and growth, and ultimately on disease processes. The present review describes some of the more important fatty acid-gene interactions in relation to health and disease in mammalian species, and focuses on the underlying cell signal mechanisms, including various transcription factors, affected by fatty acids and some of their oxygenated derivatives, e.g. the eicosanoids. The review also attempts to clarify some of the complexities of the effects of fatty acids by suggesting a possible overriding regulation by the redox status of the cell. The latter will at least stimulate controversy in this exciting area of lipid research.
Nmd3p from yeast is required for the export of the
large (60S) ribosomal subunit from the nucleus (Ho et al.,
2000). Here, we show that Nmd3p forms a stable complex
with free 60S subunits. Using an epitope-tagged Nmd3p, we
show that free 60S subunits can be coimmunoprecipitated
with Nmd3p. The interaction was specific for 60S subunits;
40S subunits were not coimmunoprecipitated. Using this
coprecipitation technique and pulse-chase labeling of ribosomal
subunit proteins we showed that Nmd3p bound nascent subunits,
consistent with its role in export. However, under conditions
in which ribosome biogenesis was inhibited (e.g., inhibition
of transcription with thiolutin, inhibition of transcription
of ribosomal protein and RNA genes in a sly1-1
mutant at nonpermissive temperature, and inhibition of
translation in a conditional prt1 mutant), Nmd3p
remained associated with 60S subunits. In addition, Nmd3Δ120,
a truncated protein that lacked a nuclear localization
signal, retained 60S binding. These results suggest that
Nmd3p recruits nascent 60S subunits into the pool of free
60S subunits and exchanges on 60S subunits as they recycle
An AlxGa1−xN/GaN two-dimensional electron gas structure with x = 0.13 deposited by molecular beam epitaxy on a GaN layer grown by organometallic vapor phase epitaxy on a sapphire substrate was characterized. Hall effect measurements gave a sheet electron concentration of 5.1×1012 cm−2 and a mobility of 1.9 × 104 cm2/Vs at 10 K. Mobility spectrum analysis showed single-carrier transport and negligible parallel conduction at low temperatures. The sheet carrier concentrations determined from Shubnikov-de Haas magnetoresistance oscillations were in good agreement with the Hall data. The electron effective mass was determined to be 0.215±0.006 m0 based on the temperature dependence of the amplitude of Shubnikov-de Haas oscillations. The quantum lifetime was about one-fifth of the transport lifetime of 2.3 × 10−12 s.
The contribution of spontaneous and piezoelectric polarization to the formation of a 2DEG in AlGaN/GaN heterostructures was investigated using undoped AlGaN/GaN structures. Hall measurements of 2DEG density on such structures with varying Al percentage (8%-27%) and varying thickness of the AlGaN layer (30-500Å) indicated that donor-like surface states at an energy of 1.42eV below the conduction band were the source of electrons in the 2DEG. Field effect transistors were fabricated on such undoped heterostructures. For an AlGaN/GaN structure with 0.27 Al mole fraction, power density in excess of 3.5 W/mm at 6 GHz with corresponding maximum PAE of 33.5% was obtained. These results exceed the best reported power performance of MBE grown GaN HFETs on sapphire, thus demonstrating the excellent capability of MBE grown GaN heterostructures for microwave power applications.
Temperature-variable Hall and Shubnikov- de Haas effects have been used to study persistent photoconductivity in an AlGaN/GaN heterojunction. At liquid helium temperatures, the mobility in this structure was close to 55000 cm2/Vs. A blue GaN-based light emitting diode was used to illuminate the sample. This illumination resulted in a persistent photocurrent, which allowed us to vary the carrier density and study the dependence of the mobility on the carrier concentration. Exposing the sample to this light resulted in an increase in the carrier density. For small increases in the density, the mobility also increased. However, unlike in previous reports by other authors, extended illumination resulted in an increase in the density and a decrease in the mobility. The initial increase in the mobility is attributed to increased screening due to the increase in the carrier density, while the decrease in the mobility may be attributed to alloy scattering.
An AlxGa1-xN/GaN two-dimensional electron gas structure with x = 0.13 deposited by molecular beam epitaxy on a GaN layer grown by organometallic vapor phase epitaxy on a sapphire substrate was characterized. Hall effect measurements gave a sheet electron concentration of 5.1×1012 cm-2 and a mobility of 1.9 × 104 cm2/Vs at 10 K. Mobility spectrum analysis showed single-carrier transport and negligible parallel conduction at low temperatures. The sheet carrier concentrations determined from Shubnikov-de Haas magnetoresistance oscillations were in good agreement with the Hall data. The electron effective mass was determined to be 0.215±0.006 m0 based on the temperature dependence of the amplitude of Shubnikov-de Haas oscillations. The quantum lifetime was about one-fifth of the transport lifetime of 2.3 × 10-12 s.
The so-called Crag formations of East Anglia are the only British examples of a sedimentary sequence that is partly Pliocene and partly early Pleistocene. They are composed of marine near-shore and estuarine shelly sands and clays, in some horizons with good pollen assemblages. The oldest unit, the Coralline Crag, has always been accepted as Pliocene. Early attempts to locate the base of the Pleistocene in that sequence were guided by the belief that its position would be indicated by evidence of a sharp drop in temperature. Thus, at the International Geological Congress in 1948, it was recommended (King and Oakley, 1949) that in England the Neogene–Quaternary boundary should be placed in the East Anglian sequence at the base of the Butleyan Red Crag, the highest and youngest of Harmer's (1902) three Red Crag “zones.” A number of authors (e.g., Boswell, 1952) subsequently proposed that it should be lowered to the base of the Red Crag, on the assumption that the transition from the underlying Coralline Crag indicated a major climatic deterioration. On the premise that the boundary was associated with the Olduvai normal paleomagnetic event, Hey (1977) and Funnell (1977) independently concluded that in East Anglia it could lie above the top of the Red Crag.
It must be emphasized that the paleomagnetic data available from the East Anglian succession are scanty (Van Montfrans, 1971, pp. 100–101), and materials suitable for radiometric dating appear to be absent.
The deposition rate of silicon dioxide from TEOS/02 capacitively-coupled plasmas increases with increasing applied rf power, increasing total pressure and decreasing wafer temperature. These dependences can be explained by a mechanism in which deposition occurs through both an ionassisted and an oxygen atom initiated pathway. The ion-induced deposition rate increases with increasing rf power density and decreasing total pressure, and is independent of wafer temperature. Assuming a well-mixed plasma, and using literature values for reaction rate parameters and rate forms for oxygen plasma reactions, the rate of atom-induced deposition was found to be independent of temperature and TEOS concentration and directly proportional to oxygen atom concentration. The model suggests that the apparent negative activation energy for deposition results from competition between deposition and thermally-activated atomic oxygen surface recombination. The derived deposition rate form is consistent with an Eley-Rideal mechanism in which the rate determining step for film deposition is oxidative attack of adsorbed TEOS or TEOS fragments by a activated oxygen.
The authors challenge the traditional balance sheet concept of the solvency of a general insurance company and put forward an emerging costs concept, which enables the true nature of the assets and liabilities to be taken into account, including their essential variability. Simulation is suggested as a powerful tool for use in examining the financial strength of a company. A simulation model is then used to explore the resilience of a company's financial position to a variety of possible outcomes and to assess the probability that the assets will prove adequate to meet the liabilities with or without an assumption of continuing new business. This suggests the need for an appropriate asset margin assessed individually for each company. The implications for the management and supervision of general insurance companies are explored. The suggestion is made that the effectiveness of supervision based on the balance sheet and a crude solvency margin requirement is limited. More responsibility should be placed on an actuary or other suitably qualified professional individual to report on the overall financial strength of the company, both to management and to the supervisory authorities.
1.1 Following the thalidomide tragedy, a Royal Commission was set up in March 1973 to examine and report on the circumstances in which anyone suffering personal injury should be entitled to compensation and on the amount, the form and the source of such compensation. The Commission also considered the extent to which dependants should be compensated for losses which they incurred arising from the injury or death of a victim. The Commission, whose chairman was Lord Pearson, took written evidence from 766 organizations or persons and oral evidence from 113. The Report of the Commission, published in March 1978, was in three volumes comprising in all 1,084 pages. Volume 2 (259 pages) contained detailed statistical information which had been produced from various sources. It is known that in many cases information had to be assembled from inadequate data, and the Commission pointed out that many of the figures were a matter of judgment. They ascribed degrees of reliability to each table, but in some cases they were probably over-optimistic. Volume 3 (280 pages) reported on practice overseas.
The incidence of volcanic pebbles in the gravels of the middle Thames basin is noted. The detailed petrography of volcanic clasts at two sites is described and found to be broadly similar to that of material from sites in East Anglia, thought to be of Welsh origin. The frequency of volcanic pebbles in the two areas is also similar. This evidence suggests that volcanic material was brought into East Anglia via the ancestral Thames.Records of volcanic rocks in the drift deposits of the upper Thames basin provide additional evidence of this route.
In the pre-Anglian Pleistocene of East Anglia and Essex are unfossiliferous gravels with pebbles of flint, quartz, quartzite, chert and volcanic rocks. All appear to belong to the Kesgrave Sands and Gravels of Rose & Allen (1976), which are largely or wholly fluviatile and probably of Beestonian age. Forty-six of the volcanic pebbles, from three different localities, have been examined microscopically. Almost all are fine-grained acid igneous rocks or vitric tuffs, evidently derived from a single suite. Various possible source-areas are considered, of which North Wales, with its Ordovician volcanics, is thought to be the most likely.