Microchemical Characterization of Alluvial Gold Grains as an Exploration Tool

There is considerable variation in the composition of native gold and the nature of minerals co-existing with it, and this reflects differences in the geological environment and chemistry of ore-forming processes. In areas where gold-bearing mineralization is subject to active fluvial erosion, especially in temperate climatic regimes, any discrete grains of native gold pass into alluvial sediment with little modification. The chemical characteristics of alluvial grains and the nature of preserved mineral inclusions provide a signature which points back to the type of source mineralization. This signature may be established using electron probe microanalysis and scanning electron microscopy and can be interpreted to provide information about the original bedrock mineralization. Identification of the type of source mineralization using the technique at an early stage in regional exploration can help focus attention on targets with the most potential economic importance.     

The electrochromic properties of sputtered nickel oxide films

Electrochromic nickel oxide films were prepared by reactive RF sputtering from a nickel target in an oxygen atmosphere. The films were deposited as a compact 40 nm layer of trivalent nickel oxide, Ni₂O₃. Reduction and oxidation of the films in 1 M KOH resulted in bleaching and coloration, respectively. Voltammetry indicated that the eventual electrochromic reaction involved the β-Ni(OH)₂/β-NiOOH couple. In situ visible spectra showed electrochromic modulation of the transmittance throughout the visible range with a peak change in transmittance of about 60% at a wavelength of 500 nm. In situ spectra in the near-infrared region indicated improved electrochromic switching in this region; the sputtered nickel oxide film exhibited about a 30% change in transmittance in comparison to less than 10% for a similar electroprecipitated nickel hydroxide film. The sputtered nickel oxide films exhibited durable electrochromic switching for over 2500 coloration/bleaching cycles, a significant improvement over the less than 500 switching cycles exhibited by electroprecipitated nickel hydroxide films.     

The design of Radiation Accident Registry

In order to provide effective monitoring and follow-up on the health effects of individuals accidentally exposed to ionising radiation, a Radiation Accident Registry (RAR) has been designed and constructed as an extension to the existing National Dose Registry (NDR). The RAR has basic functions of recording, monitoring and reporting. This type of registry is able to assist responders in preparing for and managing situations during radiological events and in providing effective follow-up on the long-term health effects of persons exposed to ionising radiation. It is especially important to register radiation-exposed people in vulnerable population groups, such as children and pregnant women, to ensure proper long-term health care and protection. Even though radiation accidents are rare, a registry prepared for such accidents could involve a large population and, in some cases, require lifetime monitoring for individuals. One of the most challenging tasks associated with RAR is the assessment of radiation dose resulting from accidents. In some cases, the assessment of radiation doses to individuals could be a process requiring the involvement of various methods. The development of fast and accurate dose assessment tools will remain a long-term challenge associated with the RAR. To meet this challenge, further research activities in radiation dosimetry for individual monitoring are needed.     

地毯用的Tencel lyocell纤维

介绍了世界主要地毯市场的需求.分析了对现用地毯材料的处理中存在的问题.阐述了Tencel纤维独具的性能,以及利用Tencel纤维生产地毯的前景.     

Leukocytes in the cervix: a quantitative evaluation of cervicitis

OBJECTIVE: To quantify the numbers of leukocytes in the normal cervix and relate these numbers to the diagnosis of cervicitis. METHODS: Isolated cell suspensions were prepared from cervical tissue recovered at hysterectomy from 37 women who had no obvious cervical disease. The percentages of CD45+ cells (leukocytes) in these preparations were determined using immunofluorescence-based flow cytometric analysis. These percentages were compared with the pathologist's assessment of cervicitis. RESULTS: Leukocytes were present in all cervical samples tested. For endocervical samples, the mean (+/- standard error of the mean [SEM]) percentage of CD45+ cells was 12.4 +/- 1.9% of cells in patients with a diagnosis of cervicitis (n = 16) and 9.1 +/- 1.1% in patients without cervicitis (n = 17). For ectocervical samples, the mean (+/- SEM) percentage was 14.8 +/- 3.0% in those with cervicitis (n = 16) and 9.5 +/- 1.6% in those without cervicitis (n = 19). The differences between samples from patients with cervicitis and those without cervicitis were not statistically significant at the .05 level. Intra- and interassay variabilities were 5.7 +/- 1.2% and 7.3 +/- 1.6%, respectively. CONCLUSION: Our study demonstrates there is a resident population of leukocytes in the cervix. Leukocyte number did not relate clearly and consistently to the diagnosis of cervicitis made by the pathologist. We suggest that the resident population of leukocytes, in the absence of other indicators of infection, may confuse determinations of cervicitis.     

Psychologists' Attitudes and Therapeutic Approaches Toward Gay, Lesbian, and Bisexual Issues Continue To Improve: An Update.

Psychologists' attitudes and approaches toward the gay, lesbian, and bisexual (GLB) lifestyle continue to change, on the basis of results from 437 responding members of the American Psychological Association. Psychologists are more likely to view an active GLB lifestyle-identity as acceptable and non-pathological, more likely to support and provide gay-affirmative therapy, and much less likely to support changing sexual orientation through psychotherapy. Female psychologists are significantly more likely to view a GLB lifestyle as accepting and to provide gay-affirmative therapy to GLB clients compared with their male counterparts. Finally, training opportunities for psychologists involving GLB issues appear to be increasing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)