Hypovitaminosis D may be associated with diabetes, hypertension and CHD. However, because studies examining the associations of all three chronic conditions with circulating 25-hydroxyvitamin D (25(OH)D) and 1,25-dihydroxyvitamin D (1,25(OH)2D) are limited, we examined these associations in the US Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial (n 2465). Caucasian PLCO participants selected as controls in previous nested case–control studies of 25(OH)D and 1,25(OH)2D were included in this analysis. Diabetes, CHD and hypertension prevalence, risk factors for these conditions and intake of vitamin D and Ca were collected from a baseline questionnaire. Results indicated that serum levels of 25(OH)D were low ( < 50 nmol/l) in 29 % and very low ( < 37 nmol/l) in 11 % of subjects. The prevalence of diabetes, hypertension and CHD was 7, 30 and 10 %, respectively. After adjustment for confounding by sex, geographical location, educational level, smoking history, BMI, physical activity, total dietary energy and vitamin D and Ca intake, only diabetes was significantly associated with lower 25(OH)D and 1,25(OH)2D levels. Caucasians who had 25(OH)D ≥ 80 nmol/l were half as likely to have diabetes (OR 0·5 (95 % CI 0·3, 0·9)) compared with those who had 25(OH)D < 37 nmol/l. Those in the highest quartile of 1,25(OH)2D ( ≥ 103 pmol/l) were less than half as likely to have diabetes (OR 0·3 (95 % CI 0·1, 0·7)) than those in the lowest quartile ( < 72 pmol/l). In conclusion, the independent associations of 25(OH)D and 1,25(OH)2D with diabetes prevalence in a large population are new findings, and thus warrant confirmation in larger, prospective studies.

Charcoal is the result of natural and anthropogenic burning events, when biomass is exposed to elevated temperatures under conditions of restricted oxygen. This process produces a range of materials, collectively known as pyrogenic carbon, the most inert fraction of which is known as black carbon (BC). BC degrades extremely slowly and is resistant to diagenetic alteration involving the addition of exogenous carbon, making it a useful target substance for radiocarbon dating particularly of more ancient samples, where contamination issues are critical. We present results of tests using a new method for the quantification and isolation of BC, known as hydropyrolysis (hypy). Results show controlled reductive removal of non-BC organic components in charcoal samples, including lignocellulosic and humic material. The process is reproducible and rapid, making hypy a promising new approach not only for isolation of purified BC for 14C measurement but also in quantification of different labile and resistant sample C fractions.

The pre-Cambrian geology in Canada is in an unsatisfactory condition, due not so much, to disagreement regarding fundamental facts and history, as to words and the control they exercise upon ideas.

Relaxation techniques have been widely used in kinetic studies of chemical reactions in homogeneous solution (Eigen & DeMayer, 1963). The principle of this method is well known: an external variable such as temperature or pressure is suddenly changed and the time course of a state parameter of the system such as concentration is recorded as it approaches a new steady value. Relaxation techniques can also be used for studying the rate of elementary processes in membranes. This method has proved particularly useful for the investigation of ion transport systems (ion carriers, channels, pumps) in artificial planar bilayer membranes. In this review we describe different relaxation techniques which have been developed for this purpose during the last years, as well as applications to a number of ion transport systems.

Homoepitaxial SrTiO3 thin films were grown on SrTiO3 (001) using Pulsed Laser Deposition (PLD). The deposition process was monitored in-situ, via both x-ray reflectivity and surface diffuse x-ray scattering measurements in the G3 experimental station at the Cornell High Energy Synchrotron Source (CHESS). Using a CCD detector in 1D, or streak-camera, mode with approximately 0.3-second time resolution, data were collected during growths performed at two substrate temperatures: 695°C and 1000°C. While the specular reflectivity oscillations for the two growths are very similar, the diffuse scattering clearly shows a distinct change in the peak position. Using Atomic Force Microscopy (AFM), we illustrate how the peak position for the diffuse lobes of scattered intensity is directly related to the distribution of single unit cell high islands on the growing surface. Thus, the peak shift of the diffuse scattering indicates an order of magnitude change in the island density.

Thirty-three strains of Fusarium species from clinical sources including F. solani, F. oxysporum, F. moniliforme, F. proliferatum, F. subglutinans and F. chlamydosporum were examined for their physiological characteristics and mycotoxin production. Of this collection 29 exhibited growth at 37 °C and 21 were resistant to cycloheximide. Two strains of F. moniliforme and two strains of F. proliferatum produced fumonisins. No strains in this collection produced detectable amounts of trichothecenes. All 18 strains of F. solani tested produced the immunosuppressive agent cyclosporin A. The cyclosporin A-producing ability of clinical isolates of F. solani may influence their pathogenic potential.

A study has been conducted on ZrC/VC alloy thin films prepared by both pulsed laser deposition (PLD) and RF magnetron sputtering. The phase formation, wear properties, and hardness of these thin films were examined. An alloy target comprised of 36% VC and 64% ZrC (atomic %) was used to deposit films at 200°, 2000°, and 400° C. The nominal film thickness was 0.6 μm. X-ray diffraction (XRD) analysis revealed these films were solid-solution alloys and showed a preference for (100) orientation for sputter-deposited films and a (110) orientation for laser deposition. More highly oriented films were obtained at elevated temperatures as evidenced by rocking curve measurements on the PLD films. The FWHM of the peaks ranged from 2.2° to 8.3° for films deposited at 400° C and 20° C, respectively.

Using time-of-flight quadmpole mass spectrometry (TOFQMS), we performed plume diagnostics to measure particle energies and the thermalization effects of the background gas. In vacuum, typical ion energies ranged from ˜5–100 eV while the neutral atoms had kinetic energies from ˜1–5 eV. Our measurements show that the background gas can be used to selectively thermalize low mass components in the plume. From measured kinetic energies and collision effects of the gas, the changes in crystallographic structure of the alloy with pressure appear to result from collision-induced effects from condensation of the Zr atoms. This ‘heavy’ atom effect may be an important new processing parameter with which to adjust film morphology and crystal texture.

A study has been conducted on the pulsed laser deposition (PLD) of transition metal carbides in order to examine alloying and phase formation in binary systems. Alternating layers of TiC/ZrC and ZrC/VC were deposited at 400 C and 5 mTorr Ar with nominal period thicknesses of 0.6 nm, 10.0 nm, and 50.0 nm. ZrC/VC x-ray diffraction analysis showed that the alloys were amorphous and the TiC/ZrC alloys were crystalline. The thicker films showed a higher degree of phase separation of the two compounds. Transmission electron microscopy confirmed the amorphous structure in the 0.6 nm ZrC/VC film, while the 50.0 nm film showed a layered structure and extremely fine grain size.

Low work function surfaces offer great promise as thermionic converters and neutral conversion surfaces due to the relative ease with which electrons may be removed. BaZrO3 surfaces were prepared using pulsed laser deposition (PLD) and their materials properties evaluated for potential use as a neutral conversion surface for space applications. Single layer films were fabricated at temperatures ranging from 110°C to 600°C, and as a function of background ambient pressure. The degree of crystallinity of the resulting films was measured using x-ray diffraction (XRD) and the surface morphology evaluated with atomic force microscopy (AFM). The film quality was found to be directly related to substrate temperature: an increase in grain size from ˜ 10 nm to >50 nm and improved crystal orientation with respect to the substrate were observed as the deposition temperature was increased from 110°C to 600°C.

We have used an electron cyclotron resonance plasma system to perform chemical vapor deposition experiments on single-crystal, (110) oriented diamond substrates. The depositions were carried out at 0.060 Torr using mixtures of methanol in hydrogen. Substrate temperatures were varied from approximately 620 to 800 °C The film morphology was examined using SEM and microstructural phase determination was attempted using micro-Raman spectroscopy. Based on the results of these experiments, we have determined general trends for the characteristics of films deposited on diamond from the ECR plasma at low pressures and temperatures.

We report on the development of a new, integrable photoconductive-type detector based on low-temperature-grown GaAs. The detector has a response time of 1.2 ps and a 3-dB bandwidth of 375 GHz. The responsivity is 0.1 A/W. This is the fastest photodetector reported to date. We discuss the unique properties of this device, including its performance as functions of both light intensity and bias voltage.

In a little over 400 pages Robert T. Handy's volume of the Oxford History of the Christian Church surveys more than four hundred years, two countries of vast geographical extent, almost 300 million people, fifteen churches claiming over two million members each, innumerable smaller churches, denominations and sects. One cannot but admire the tenacity with which he has carried out this daunting task, and be grateful for a critical bibliography of over 30 pages which will be invaluable for anyone who requires a quick guide to the literature on almost any aspect of American or Canadian Church history. The presentation is clear, and the stream—or torrent—of information is handled with skill.