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Surface analysis of air-sensitive samples is difficult without controlled-environment sample transfer tubes or expensive vacuum transfer suitcases. Through the use of vacuum sealing and commercial magnets, we demonstrate a concept for a sample holder that can be used to transfer samples from an inert environment directly into an X-ray photoelectron spectrometer. Our results show the efficacy of the holder through analysis of an air-sensitive CuCl powder, where oxidation was not observed when using the sample holder. This method offers a simple, low-cost alternative to enable routine air-free measurements in instrumentation with vacuum-controlled sample introduction chambers. Our aim with this report is to share the design so that this sample holder can be made anywhere where there is access to a basic machine shop.

Phenol-type components, such as butylated hydroxytoluene (BHT), are used as antioxidants (AOs) to enhance the thermo-oxidative stability of kerosene-type Jet A-1 fuel. Although the antioxidative effect of BHT is well known and often published, there is far less information about the degradation products of BHT in fuels and their impact on stability toward oxidation. In order to monitor a time-resolved depletion of BHT in model kerosene, an artificial alteration method adapted for regular sampling was applied. Subsequently, the molecular structure of degradation products of BHT was identified by gas chromatography with electron impact ionization mass spectrometry (GC-EI-MS). For the quantification of the residual BHT as well as the two representatives of degradation products, namely, 3,5-di-tert-butyl-4-hydroxybenzaldehyde (HBA) and 2,6-di-tert-butyl-p-benzoquinone (BQ), an analytical technique comprising a GC-EI triple quadrupole mass spectrometer run in the MS/MS mode was developed. The limit of detection (LOD) and the limit of quantification (LOQ) for BHT, BQ, and HBA were determined below 1 ppb. The formation of BQ and HBA was observed shortly after the nascent degradation of BHT, while an increase of oxidation products derived from the fuel ascended remarkably after a full depletion of both the initial AO BHT and the monitored oxidation products BQ and HBA. As the evolution of BQ and HBA followed a characteristic trend, these compounds can be used as markers to reliably predict the residual time until a total consumption or a predefined threshold of BHT is reached. This way, the quality management of in-service or stored kerosene-type fuels is enhanced.

Within the framework of the EU project ESWIRP, the particle image velocimetry (PIV) using high-speed camera and laser has been used to measure the turbulent flow in the wake of a stalled aircraft wing. The measurements took place on the common research model provided by NASA in the pressurized cryogenic European Transonic Wind tunnel. A specific cryoPIV system has been used and adapted for using high-speed PIV components under the cryogenic conditions of the wind tunnel facility. First results are presented comprising transonic and subsonic stall conditions at realistic flight Reynolds numbers of 11.6 and 30 million, respectively.

Optical techniques that use a spectral range of photon energies larger than the band gap are very sensitive for structural characterization of semiconductor nanocrystals. Techniques that can measure the change of polarization during reflection from bulk or thin film samples reveal high sensitivity for both the layer thickness and the refractive index. From one spectroscopic ellipsometric measurement performed in a range of 0.7-6.5 eV within 1 s using a standard multi-channel ellipsometer not only the thickness and the dielectric function of the film, but a range of derived material properties like the crystallinity or the size and volume fraction of nanocrystals can be determined indirectly. The quality of the measurement is not any more a question of instrumentation, but rather a question of interpretation and proper modeling. In this paper we summarize what parameters can be determined, and we present a method for the reliable fitting of numerous parameters.

Compound lipophilicity connected to ADME(T)a has great importance in drug development and it has to be evaluated by the generally used drug developmental process. In addition to the importance of lipophilicity in ADMET, recently it has been reported that lipophilicity of small molecules correlates with their antiproliferative activity because of certain specific hydrophobic and lipophilic interactions. Due to the complexity of ADME(T) parameters an efficient and fast method is needed to characterize the many promising candidate lead molecules as a preselection in order not to be rejected from the latter phase of drug development. In the present paper we provide an overview of the importance of lipophilicity of drug candidates for biological action and for ADME(T) and describe a novel approach for drug-likeness characterization of a molecular library using correlation study between lipophilicity and biological activity. Lipophilicity and molecular characteristics have been measured, predicted and optimized for a diverse library from which the best members have been selected to describe their biological, chemical and drug-likeness properties. Molecules were selected from the family of ,-unsaturated ketones and thorough HPLC characterization for lipophilicity and morphological, antiproliferative and flow cytometric studies were carried out on them. Based on the results 17 member isochromanone library including E and Z geometric isomers were selected for further characterization. In this focused library linear correlation has been found between the calculated and measured lipophilicity and significant parabolic correlation was found between the antiproliferative effect and lipophilicity. Using our efficient and fast method, from a diverse library, we identified an outstandingly effective inhibitor of A431 tumour cell growth via a PARPa cleavage dependent apoptosis. In summary the optimized HPLC analyses of lipophilicity combined with the cell-culture assay, introduced above, resulted in the determination of an optimal lipophilicity range. This optimized lipophilicity range should be used in designing novel antiproliferative compounds.

Lutein ((all-E,3R,3R,6R)-,-carotene-3,3-diol) is the main carotenoid that can be found in light-harvesting complexes of higher plants and it is also involved in human diet. In the extracts of human plasma the 3-epimer of lutein, several geometrical isomers, dehydration and oxidation products of lutein have been identified. It was also established that lutein reduces the risk of AMD (age-related macular degeneration). This mini review focuses on the in vitro and in vivo transformations of lutein.

The article offers sample itineraries and instructions on what activities, restaurants, and locations should be included in the travel plan when on vacation at California's Central Coast.

The article evaluates several recommended gifts for the holiday season including the Nintendo Wii video game console, the Elsa Paretti pendant from Tiffany, and the EOS 40D digital camera from Canon.

The experimental investigation of unsteady complex flow fields in wind tunnels requires advanced measurement techniques. The most important of such image based measurement techniques are those for the measurement of planar flow velocity fields, planar pressure distribution, model location and deformation, model temperature and quantitative high speed flow visualization. The applications as carried out by DLR range from low speed flows to transonic flows, from high lift configurations to propellers and rotors, from wake vortex investigations in catapult facilities and water towing tanks to investigations of vortex break down phenomena on delta wings. The capability to use image based measurement techniques in transonic flows requires dedicated technical developments and experienced scientists due to the special environment of a transonic wind tunnel. In this paper an overview of the state-of-the art of the application of image based measurement techniques in transonic flows as performed by DLR's Institute of Aerodynamics and Flow Technology will be given.

Three pairs of primary-secondary diol acceptors have been exposed to armed, disarmed, and n-pentenyl ortho ester glycosyl donors in glycosidation reactions. It is shown that the regioselectivity of those glycosylations is greatly influenced by the armed, disarmed, or ortho ester nature of the glycosyl donors. The selectivities observed have been used to devise efficient in situ three-component glycosylations involving two donors and one acceptor.

Copyright of Canadian Diversity / Canadian Diversité is the property of Association for Canadian Studies and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Few complaints of systemic racial discrimination in employment have been heard and substantiated by human rights tribunals and boards of inquiry, in part because of the challenge of gathering persuasive evidence. A three-dimensional diagnostic framework is proposed, highlighting numerical representation and distribution, employment systems, and organizational culture. For each dimension, examples of types of qualitative and/or qualitative evidence are suggested, using research approaches borrowed from the social sciences, employment equity and pay equity. [ABSTRACT FROM AUTHOR]

ABSTRACTClostridium difficileis a major nosocomial pathogen responsible for pseudomembranous colitis and many cases of antibiotic-associated diarrhea. Because of potential relapse of disease with current antimicrobial therapy protocols, there is a need for additional and/or alternative antimicrobial agents for the treatment of disease caused by C. difficile. We have synthesized a systematic series of 14 structurally simple bismuth compounds and assessed their biological activities against C. difficileand four other gastrointestinal species, includingHelicobacter pylori. Here, we report on the activities of six compounds that exhibit antibacterial activities againstC. difficile, and some of the compounds have MICs of less than 1 μg/ml. Also tested, for comparison, were the activities of bismuth subcitrate and ranitidine bismuth citrate obtained from commercial sources. C. difficileandH. pyloriwere more sensitive both to the synthetic bismuth compounds and to the commercial products than were Escherichia coli, Pseudomonas aeruginosa, and Proteus mirabilis, and the last three species were markedly resistant to the commercial bismuth salts. Testing with human foreskin fibroblast cells revealed that some of the synthetic compounds were more cytotoxic than others. Killing curves for C. difficiletreated with the more active compounds revealed rapid death, and electron microscopy showed that the bismuth of these compounds was rapidly incorporated by C. difficile. Energy dispersive spectroscopy X-ray microanalysis of C. difficilecells containing electron-dense material confirmed the presence of internalized bismuth. Internalized bismuth was not observed inC. difficiletreated with synthetic bismuth compounds that lacked antimicrobial activity, which suggests that the uptake of the metal is required for killing activity. The nature of the carrier would seem to determine whether bismuth is transported into susceptible bacteria like C. difficile.

The recognition of the role of Helicobacterpylori in the pathogenesis of peptic ulcer disease hasled to renewed interest in bismuth pharmacology sincebismuth compounds have both anti-Helicobacter pylori and ulcer healing properties. The precisechemical structure of current bismuth compounds is notknown. This has hindered the development of new andpotentially more efficacious formulations. We havecreated two new compounds,2-chloro1,3-dithia-2-bismolane (CDTB) and1,2-[bis(1,3-dithia-2-bismolane)thio]ethane (BTBT), withknown structure. In a rat model of gastric ulceration,BTBT was comparable to, and CDTB was significantly less effective thancolloidal bismuth subcitrate in healing cryoprobeinducedulcers. However, both BTBT and CDTB inhibited H. pylorigrowth in vitro at concentrations <1/10 that of colloidal bismuth subcitrate. The effects onulcer healing are not mediated by suppression of acidsecretion, pepsin inhibition, or prostaglandinproduction. Since all treated animals received the same amount of elemental bismuth, it appears thatthe efficacy of bismuth compounds varies with compoundstructure and is not simply dependent on the delivery ofbismuth ion. Because the structure of the novel compounds is known, our understanding of therelationship of bismuth compound structure and tobiologic activity will increase. In the future it may bepossible to design other novel bismuth compounds with more potent anti-H. pylori and ulcer healingeffects.

The purpose of this paper is to identify problems in ethnic studies and to discuss several teaching approaches that we have used in an attempt to meet some of these needs. Some problems of research and teaching in the field of ethnic studies include: 1) lack of awareness of the current social meaning of ethnicity; 2) data deficiencies; 3) lack of sensitivity to problems of scale in spatial analysis; 4) the separation between teaching and research; and 5) limitations imposed by discipline-bounded viewpoints. The research-teaching approaches used in the effort to counter these problems were: 1) migration histories of students' families; 2) studies of ethnic settlement at interregional, intraregional, and intraurban scales; 3) the urban ethnic field trip; and 4) the metropolitan Detroit ethnic mapping project.

The properties of Ge-HfO2and Ge-ZrO2films were studied versus Ge content and annealing temperature by means of Raman scattering, FTIR and X-ray diffraction methods. Ge-HfO2films with [Ge]<5 at.% were polycrystalline, whereas higher Ge content stabilized amorphous structure that was stable for T<600°C. The T increase caused the formation of Ge clusters and tetragonal HfO2phase. This latter appeared at T=600-670°C, while the Ge clusters crystallized at T=700-800°C. Unlike to Ge-rich HfO2films, as-deposited Ge-ZrO2films and those annealed at T≤600°C were amorphous. In these films, formation of Ge clusters and their crystallization occurred at T=640-700°C depending on Ge content, whereas ZrO2phase crystalized at T=680-700°C that allowed to form Ge nanocrystals in amorphous matrix at T=640-680°C. For T>800°C, the films showed appearance of monoclinic HfO2or ZrO2phases that was explained by the Ge content decrease via volatile GeO formation. Obtained results supported theoretical prediction of the stability of tetragonal phases in these oxides via Ge doping. However, our results showed also some difference in the phase separation process of Ge-rich HfO2and Ge-rich ZrO2upon thermal treatment.

An efficient iterative, orthogonal protocol based on the regioselective glycosyl coupling of d-mannose polyols with, partially unprotected, n-pentenyl orthoester donors permits the synthesis of linear and branched oligosaccharides with minimal protecting group tampering.

Conservation biology draws from a diverse tange of academic fields. Already a number of textbooks are available on the subject. This book is the first attempt to place the concepts of conservation biology into a uniquely Australian context. The book aim1l to provide an introduction to the principles of conservation biology and supply information on the main quantitative methods and procedures important in detecting and solving conservation problems in Australia.

The authors assessed whether the lack of weekend cardiac test availability significantly contributed to weekend delays in hospital discharge for “low-risk” chest pain patients. Mean lengths of stay were compared for late-week versus early-week admissions. Patients with late-week admissions had a 19% greater length of stay than did patients admitted earlier in the week (2.36±1.87 vs 1.91±1.21 days, p=0.10, with p=0.015 after adjusting for severity of illness). Cardiac diagnostic tests were ordered for only4%of study patients. Therefore, the “weekend effect” existed in an environment where cardiac diagnostic tests were infrequently ordered.

Understanding interface processes has been gaining crucial importance in many applications of biology, chemistry, and physics. The boundaries of those disciplines had been quickly vanishing in the last decade, as metrologies and the knowledge gained based on their use improved and increased rapidly. Optical techniques such as microscopy, waveguide sensing, or ellipsometry are significant and widely used means of studying solid‐liquid interfaces because the applicability of ions, electrons, or X‐ray radiation is strongly limited for this purpose due to the high absorption in aqueous ambient. Light does not only provide access to the interface making the measurement possible, but utilizing the phase information and the large amount of spectroscopic data, the ellipsometric characterization is also highly sensitive and robust. This article focuses on ellipsometry of biomaterials in the visible wavelength range. The authors discuss the main challenges of measuring thickness and optical properties of ultra‐thin films such as biomolecules. The authors give an overview on different kinds of flow cells from conventional through internal reflection to combined methods. They emphasize that surface nanostructures and evaluation strategies are also crucial parts of in situ bioellipsometry and summarize some of the recent trends showing examples mainly from their research. In this Feature Article, the recent results of in situ bioellipsometryare summarized. The usual flowcells for ellipsometric measurements are presented, emphasizing their performance. Advanced techniques for data evaluation, the possibility of combining bioellipsometric measurements with other methods, and the benefits of various surface nanostructures are also discussed.

To characterize zirconium surfaces in forms of tubes and plates for nuclear applications, ellipsometry has been used. It has been shown earlier that ellipsometry can be used even on the surface of tubes with a diameter of 9.1 mm, when applying proper focusing. Reference refractive indices have also been determined for both zirconium and zirconium oxide, and demonstrated the capability of ellipsometry for the determination of the thickness and refractive index of the surface oxide applying different oxidation parameters. In this study, processed zirconium surfaces using the technique developed in author's previous work is characterized. Both ultra violet‐visible‐near infrared and mid‐infrared ellipsometry to study the thicknesses of the surface layers as well as the dielectric functions of both the layers and the substrate are used. A heat cell that allows multiple angle of incidence ellipsometry measurement at elevated temperatures is also developed. This setup is used to monitor the temporal behavior of hydrogenated and oxidized zirconium surfaces. Ellipsometry is used for the in situ characterization of zirconium surfaces in forms of tubes and plates for nuclear applications, using a special cell for annealing. The capability of ellipsometry is demonstrated for the determination of the thickness and reference refractive indices of both zirconium and zirconium‐oxide in a wide spectral range.