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The Australian Bureau of Meteorology has constructed a new 1280-MHz radar wind profiler. Key features include a state-of-the-art digital transceiver system and modern peak detection algorithms for obtaining high quality wind estimates, even in the presence of clutter. The design of the radar is described in detail, and the performance of the radar in its current configuration and some examples of the data are given. The paper concludes with the planned upgrades to the system. [ABSTRACT FROM AUTHOR]

Examines the role of participation in the evaluation and implementation of community development projects. Increase in the advocacy of the participatory approach as a prerequisite of projects; Conditions for the success of participatory approaches; Description of examples from diverse geographic and subject-matter backgrounds.

Abstract We have reported on the implantation of boron ion into hexagonal boron nitride (h -BN) material to aid the nucleation of cubic boron nitride nanocrystals (n c -BN).Single crystal h -BN was implanted with boron ion at 150 keV at fluences of the order of 1015 and 1017 ions/cm2 at room temperature. High Angle Annular Dark-Field Scanning Transmission Electron Microscopy (HAADF-STEM) mapping showed a variation in image contrast in samples irradiated to a fluence of 1 × 1015 ions/cm2. As predicted by Stopping Range and Ions in Materials (SRIM) calculations, the implanted region with the highest damage density appeared to have a bright contrast in HAADF-STEM which represented the high density c -BN symmetry. High Resolution Transmission Electron Microscopy (HRTEM) and electron diffraction measurements showed regions with n c -BN for samples implanted with low fluences and amorphous BN after implantation with high fluences indicating a fluence-related phase transition in BN. Raman spectroscopy showed the emergence of longitudinal optical frequency mode associated with c -BN after implantation. Graphical abstract Unlabelled Image Highlights • Boron ion implantation induces a phase transformation of hexagonal BN to cubic BN. • There exists a threshold fluence above which the material becomes amorphous. • This is a novel study where high angle annular dark field scanning transmission electron microscopy has been used to analyse boron implantation in BN. [ABSTRACT FROM AUTHOR]

Comments on the reliability of data used in the article "Migration to and from Bangkok," by Larry Sternstein. Flaws in the registration system that might explain the deviations between Sternstein's conclusions and the conclusion of others who have worked on migration in Thailand; Contradiction in the suggestion that education was the most important attraction for migrants to the city.

The development of the first Australian C-band polarimetric/Doppler meteorological radar system (C-POL) is described. Motivated by the need to obtain improved rainfall estimation and the vertical profile of hydrometeors, C-POL was developed jointly by the Bureau of Meteorology (BOM), the Commonwealth Scientific and Industrial Research Organisation of Australia, and the National Center for Atmospheric Research. C-POL is based on a standard operational C-band radar employed by the BOM but modified to be capable of transmitting linear horizontal and vertical polarizations and receiving the co- and cross polarizations on a pulse-to-pulse basis. Standard variables extracted include horizontal reflectivity (Z[subHH] ), radial velocity (V[subr]), spectral width (sigma[subv]), differential reflectivity (Z[subDR]), differential phase shift (phi[subDP]), and zero lag correlation coefficient [ rho[subHV](0)]. With the addition of a second receiver chain, the linear depolarization ratio will soon be available. Initial results with the radar are discussed to give examples of the data quality, as well as some of the problems inherent in using a C-band radar in the Tropics. [ABSTRACT FROM AUTHOR]

The gas-detecting ability of nanostructured ZnO has led to significant attention being paid to the development of a unique and effective approach to its synthesis. However, its poor sensitivity, cross-sensitivity to humidity, long response/recovery times and poor selectivity hinder its practical use in environmental and health monitoring. In this context, the addition of noble metals, as dopants or catalysts to modify the ZnO surface has been examined to enhance its sensing performance. Herein, we report preparation of Pd-loaded ZnO nanoparticles via a chemical precipitation approach. Various Pd loadings were employed to produce surface-modified ZnO nanostructure sensors, and their resulting NH3 sensing capabilities both in dry and humid environments were investigated. Through a comparative gas sensing study between the pure and Pd-loaded ZnO sensors upon exposure to NH3 at an optimal operating temperature of 350 °C, the Pd-loaded ZnO sensors were found to exhibit enhanced sensor responses and fast response/recovery times. The influence of Pd loading and its successful incorporation into ZnO nanostructure was examined by X-ray diffraction, high resolution-transmission electron microscopy, and X-ray photoelectron spectroscopy. XPS studies demonstrated that in all samples, Pd existed in two chemical states, namely Pd° and Pd2+. The possible sensing mechanism related to NH3 gas is also discussed in detail. [ABSTRACT FROM AUTHOR]

Abstract Silicon (Si) has been the most widely used semiconductor for decades, playing an important role in the field of electronics, energy conversion and energy storage. Because of their unique morphological energy band characteristics, Si nanostructures exhibit superior performance in many applications in comparison with their bulk counterparts. In this study, the effects of thermal annealing on elemental composition and morphological properties of palladium metal thin films grown on c-Si substrates were investigated. Palladium (Pd) thin films of different thicknesses were deposited on Si (1 0 0) with and without native oxide layers by electron beam evaporation and annealed in vacuum at 600 °C for two hours. Scanning electron microscopy (SEM) studies have shown that the surface morphology showed an effective dewetting in individual droplets and islands which further coalesce into bigger islands. Rutherford backscattering spectrometry (RBS) and electrical measurements analyses revealed the diffusion of the Si substrate into the Pd layer during annealing. This contribution will discuss the effects of the metal layer thickness as well as the native oxide on the metal thin films. [ABSTRACT FROM AUTHOR]

Water quenching of unmilled Ti compact has yielded martensitic-type laths and fishbone-type twinned microstructures, with α', α'' and FCC phases induced. Upon quenching 30 h milled and (0+30) h mixed powders at 1200 °C, α', FCC, tetragonal and BCC phases were detected using XRD. [ABSTRACT FROM AUTHOR]

Introduction Approximately 2.4–7.5% of patients with ulcerative colitis (UC) may also be diagnosed with primary sclerosing cholangitis (PSC). The risk of colorectal carcinoma (CRC) or dysplasia (CRD) has been reported to be fourfold higher in patients with PSC and UC compared to UC alone. The objective of this study is to determine the prevalence of undiagnosed PSC in UC patients with CRC or CRD. Methods 19 patients with histologically confirmed UC and CRC or CRD, with normal liver function and no prior imaging suggestive of PSC were identified. Patients had a magnetic resonance cholangiogram (MRC) and blood tests taken for pANCA, ANA, IgG and subclasses and HLA typing. Medical case notes, laboratory data and endoscopic records were reviewed retrospectively. MRCs were obtained from 21 healthy volunteers and 22 patients with established PSC to act as negative and positive controls, respectively. The Student's t test and χ test were used for analysis where appropriate. Results 26 patients met the inclusion criteria, of which 19 patients were recruited. The median age was 67 years (range 52–87) with a male predominance (74%). 15 patients (79%) had extensive and 4 (21%) left-sided colitis. Two patients (10%) had CRC, 6 (32%) high-grade and 11 (58%) low-grade CRD. 17 patients (89%) had CRC or CRD in the left colon. Two out of 19 patients (10%) had biliary abnormalities consistent with PSC on MRC. All 21 healthy volunteers had no evidence of PSC on MRC. All 22 PSC patients had characteristics of PSC on MRC. Both patients with evidence of PSC had a quiescent pancolitis and a mild disease course, with no acute admissions, immunosuppressive or biological therapy for colitis. One patient had high-grade CRD and the other CRC in the left colon. Neither patient had a positive pANCA or ANA. One had HLA haplotypes known to be associated with PSC as well as a raised IgG and IgG4. There was no difference between the median ages, duration of IBD, family history or presence of extra-intestinal manifestations of the two groups. No patient has had a liver biopsy. Conclusion This small study of patients with UC and CRC or CRD and normal liver function has demonstrated unsuspected biliary abnormalities consistent with PSC on MRC, in 2 of 19 patients. Previous work in our group has suggested a comparable prevalence of PSC in patients with extensive UC and normal LFTs. Larger studies are required to explore the relationship between possible undiagnosed PSC and the development of CRC/CRD in IBD patients. This may help to stratify screening strategies in the future. [ABSTRACT FROM PUBLISHER]

The article discusses a study which investigated the patterns of cigarette purchase in four nations and its association with smoke cessation using the results from the International Tobacco Control Four Country Survey (ITC-4). It reveals that smokers who bought from a low/untaxed source on their recent purchase have lesser chance to have tried to cease smoking. It notes that smoke cessation attempts are lower among purchasers of low/untaxed cigarettes than those buyers of full-priced cigarettes. INSET: What this paper adds.

One hundred seventy elderly women with stage II breast cancer, stratified on the basis of the number of positive axillary nodes and estrogen receptor status, were randomly assigned to receive tamoxifen or placebo for 24 months in a prospective, double-blind, adjuvant trial. The median age was 71 years with a range from 65 to 84 years. The overall percentage of patients disease-free at 4 years was 76% for those given tamoxifen and 52% for those given placebo (p = 0.0004). Benefit was seen in all subgroups of patients treated with tamoxifen. Two years of tamoxifen therapy represents an effective postoperative adjuvant treatment for elderly women with stage II breast cancer, resulting in improved time to relapse, statistically fewer distant first recurrences, and minimal toxicity. No improvement in overall survival has been seen yet. [ABSTRACT FROM AUTHOR]