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Noticeable Differences (noticeable + difference)
Selected AbstractsMono(aryloxido)Titanium(IV) Complexes and Their Application in the Selective Dimerization of EthyleneEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 20 2009Jean-Benoit Cazaux Abstract We report on the synthesis of mono(aryloxido)titanium(IV) complexes of general formula {Ti[O(o -R)Ar]X3}, with X = OiPr, ArO = 2- tert -butyl-4-methylphenoxy and R = CMe3 (2a), CMe2Ph (2b) and CH2NMe2 (2c). Attempts to reach pure mono(aryloxido) complexes when R = CH2NMe(CH2Ph) (2d) or CH2N(CH2Ph)2 (2e) were unsuccessful. When R = CH2OMe, the analogous mononuclear complex was not obtained, and instead, a dinuclear complex [(2- tert -butyl-4-methyl-6-methoxymethylphenoxy) TiCl(OiPr)(,2 -OiPr)2TiCl(OiPr)2] (3) was formed. Complexes 2b and 3 were characterized by single-crystal X-ray diffraction. The former contains a tetrahedrally coordinated TiIV centre, whereas in the latter the aryloxido ligand behaves as a chelating,bridging ligand between the two, chemically very different metal centres that form two face-sharing octahedra. Different synthetic approaches starting from [Ti(OiPr)4] or [TiCl(OiPr)3] were evaluated and are discussed. The hemilabile behaviour of the aryloxido ligand resulting from reversible coordination of its side arm was studied by variable-temperature 1H NMR spectroscopy for 2c (R = CH2NMe2). Complexes 2a,d were contacted with ethylene and AlEt3 as cocatalyst. When activated with AlEt3 (3 equiv.) at 20 bar and 60 °C, complex 2c exhibits interesting activity (2100 g/gTi/h) for the selective dimerization of ethylene to 1-butene (92,% C4=; 99+% C4=1). Noticeable differences in catalyst activity were observed when the R group was modified. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Feeding ecology of silverperch, Terapon plumbeus Kner, and the impact of fish-pens in Laguna de Bay, PhilippinesJOURNAL OF APPLIED ICHTHYOLOGY, Issue 6 2000M. Kock Summary Aquaculture is an important factor in the fishery of Laguna de Bay in the Philippines; fish-pens and net-cages covered ,10% of the lake surface in the late 1990s. The present study was carried out to assess the possible influences of aquaculture on a wild fish species, silverperch, Terapon plumbeus Kner, with a special emphasis on the feeding ecology of this fish. For the purposes of the investigation, 24-h samples were taken at 2-month intervals close to a fish-pen as well as in open water over a one-year period to acquire more information on this species. Significant differences in standard length and total weight were found between stations and sampling months. In open water, a mean standard length of 53.6 mm and a mean total weight of 4.2 g were found, whereas close to the fish-pen, the corresponding values were 57.6 mm and 5.4 g, respectively. The maximum mean standard length was attained around December 1996 and February 1997 (59.5 mm in open water; 66.1 mm close to the fish-pen), and the minimum was found in June 1996 (49.1 mm in open water; 46.2 mm close to the fish-pen). Noticeable differences were found in the food spectrum between the two sampling stations. Zooplankton, the major food source at both stations, was more important in the stomach content of fish in open water. The same was true for insects (i.e. chironomid larvae), although these did not make up such a large fraction of the diet. On the other hand, close to the fish-pen, aufwuchs- algae, phytoplankton and fish were more important. Generally, benthic organisms were consumed more frequently close to the fish-pen. Zooplankton was more important in the diet of smaller fish. In all size groups, the importance of zooplankton decreased during the rainy season. [source] Solid-state ESR differentiation between racemate versus enantiomerCHIRALITY, Issue 4 2006Pavel A. Levkin Abstract Noticeable differences between solid-state ESR spectra of enantiopure and racemic single crystals as well as powders of 2,2,5,5-tetramethylpyrrolidine-3-carboxamide-1-oxyl have been observed. Possible reasons of this fact are proposed. Chirality, 2006. © 2006 Wiley-Liss, Inc. [source] Chemical variability of Artemisia vulgaris L. essential oils originated from the Mediterranean area of France and CroatiaFLAVOUR AND FRAGRANCE JOURNAL, Issue 5 2003I. Jerkovic Abstract The essential oils of Artemisia vulgaris L. originating from France and Croatia were subjected to detailed GC,MS analysis in order to determine possible similarities and differences between them and their chemical compositions, depending on the stage of development. Plant materials were collected in Provence (France) and Dalmatia (Croatia) at four different stages of development: vegetative (June), buds (July), ,owering (August) and seeding (September). Comparison of the chemical composition and content, depending on phenological stages in both localities, shows qualitative similarity, but also the noticeable difference in the amounts of most components. First, the chemical composition of main compounds is very different; Croatian oils are rich in hydrocarbons, which are absent or present in low amounts in French oils. Also, with regard to the yield of essential oils, the yields from Croatian oils were higher (0.09,0.61%) than these from French oil (0.04,0.15%) at each development stage, respectively. Copyright © 2003 John Wiley & Sons, Ltd. [source] Perturbation theory and excursion set estimates of the probability distribution function of dark matter, and a method for reconstructing the initial distribution functionMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 1 2008Tsz Yan Lam ABSTRACT Non-linear evolution is sometimes modelled by assuming there is a deterministic mapping from initial to final values of the locally smoothed overdensity. However, if an underdense region is embedded in a denser one, then it is possible that its evolution is determined by its surroundings, so the mapping between initial and final overdensities is not as ,local' as one might have assumed. If this source of non-locality is not accounted for, then it appears as stochasticity in the mapping between initial and final densities. Perturbation theory methods ignore this ,cloud-in-cloud' effect, whereas methods based on the excursion set approach do account for it; as a result, one may expect the two approaches to provide different estimates of the shape of the non-linear counts in cells distribution. We show that, on scales where the rms fluctuation is small, this source of non-locality has only a small effect, so the predictions of the two approaches differ only on the small scales on which perturbation theory is no longer expected to be valid anyway. We illustrate our results by comparing the predictions of these approaches when the initial,final mapping is given by the spherical collapse model. Both are in reasonably good agreement with measurements in numerical simulations on scales where the rms fluctuation is of the order of unity or smaller. If the deterministic mapping from initial conditions to final density depends on quantities other than the initial density, then this will also manifest as stochasticity in the mapping from initial density to final. For example, the Zeldovich approximation and the ellipsoidal collapse model both assume that the initial shear field plays an important role in determining the evolution. We compare the predictions of these approximations with simulations, both before and after accounting for the ,cloud-in-cloud' effect. Our analysis accounts approximately for the fact that the shape of a cell at the present time is different from its initial shape; ignoring this makes a noticeable difference on scales where the rms fluctuation in a cell is of the order of unity or larger. On scales where the rms fluctuation is 2 or less, methods based on the spherical model are sufficiently accurate to permit a rather accurate reconstruction of the shape of the initial distribution from the non-linear one. This can be used as the basis for a method for constraining the statistical properties of the initial fluctuation field from the present-day field, under the hypothesis that the evolution was purely gravitational. We illustrate by showing how the highly non-Gaussian non-linear density field in a numerical simulation can be transformed to provide an accurate estimate of the initial Gaussian distribution from which it evolved. [source] Properties of nisin-incorporated polymer coatings as antimicrobial packaging materialsPACKAGING TECHNOLOGY AND SCIENCE, Issue 5 2002Young-Min Kim Abstract Nisin was incorporated into binder solutions of acrylic polymer and vinyl acetate-ethylene co-polymer, and then coated on to paper. Diffusive migration of incorporated nisin and the antimicrobial activity of the polymer coatings were investigated in order to understand the way of controlling nisin migration and the extent of microbial suppression by the coated paper. Vinyl acetate,ethylene co-polymer exhibited a faster rate and higher degree of migration into aqueous food simulant solutions compared to acrylic polymer, and also exhibited a higher degree of suppression against Micrococcus flavus ATCC 10240 inoculated into the microbial medium. Addition of NaCl, sugar and citric acid to water significantly reduced the rate of diffusion of nisin in the case of acrylic polymer, while only slight change was observed due to the additive for vinyl acetate-ethylene co-polymer. The simulant type slightly affected the equilibrated migration level of nisin. When the nisin-incorporated coatings were in contact with pasteurized milk and orange juice at 10°C, significant suppression of total aerobic bacteria and yeasts was observed without any noticeable difference between the two types of coatings. Copyright © 2002 John Wiley & Sons, Ltd. [source] Structural and photoluminescence studies of erbium-implanted nanocrystalline silicon thin filmsPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 9 2009M. F. Cerqueira Abstract Hydrogenated amorphous and nanocrystalline silicon thin films deposited by hot wire (HW) and radio-frequency plasma-enhanced chemical vapour deposition (RF-PECVD) were erbium-implanted. Their pre-implantation structural properties and post-implantation optical properties were studied and correlated. After 1,h annealing at 150,°C in nitrogen atmosphere only amorphous films showed photoluminescence (PL) activity at 1.54,µm, measured at 5,K. After further annealing at 300,°C for 1,h, all the samples exhibited a sharp PL peak positioned at 1.54,µm, with an FWHM of ,5,nm. Amorphous films deposited by HW originated a stronger PL peak than corresponding films deposited by RF, while in nanocrystalline films PL emission was much stronger in samples deposited by RF than by HW. There was no noticeable difference in Er3+ PL activity between films implanted with 1,×,1014 and 5,×,1015,atoms,cm,2 Er doses. [source] A metabolomic study of substantial equivalence of field-grown genetically modified wheatPLANT BIOTECHNOLOGY JOURNAL, Issue 4 2006John M. Baker Summary The ,substantial equivalence' of three transgenic wheats expressing additional high-molecular-weight subunit genes and the corresponding parental lines (two lines plus a null transformant) was examined using metabolite profiling of samples grown in replicate field trials on two UK sites (Rothamsted, Hertfordshire and Long Ashton, near Bristol) for 3 years. Multivariate comparison of the proton nuclear magnetic resonance spectra of polar metabolites extracted with deuterated methanol,water showed a stronger influence of site and year than of genotype. Nevertheless, some separation between the transgenic and parental lines was observed, notably between the transgenic line B73-6-1 (which had the highest level of transgene expression) and its parental line L88-6. Comparison of the spectra showed that this separation resulted from increased levels of maltose and/or sucrose in this transgenic line, and that differences in free amino acids were also apparent. More detailed studies of the amino acid composition of material grown in 2000 were carried out using gas chromatography-mass spectrometry. The most noticeable difference was that the samples grown at Rothamsted consistently contained larger amounts of acidic amino acids (glutamic, aspartic) and their amides (glutamine, asparagine). In addition, the related lines, L88-6 and B73-6-1, both contained larger amounts of proline and ,-aminobutyric acid when grown at Long Ashton than at Rothamsted. The results clearly demonstrate that the environment affects the metabolome and that any differences between the control and transgenic lines are generally within the same range as the differences observed between the control lines grown on different sites and in different years. [source] Comparison of anterior chamber depth measurements taken with the Pentacam, Orbscan IIz and IOLMaster in myopic and emmetropic eyesACTA OPHTHALMOLOGICA, Issue 4 2009Canan Asli Utine Abstract. Purpose:, This study determined to assess the degree of agreement between anterior chamber depth (ACD) measurements obtained using three different devices and to analyse the relationship between ACD and spherical equivalent (SE) refraction. Methods:, In this cross-sectional study, 42 eyes of 42 patients with a mean SE of , 4.69 ± 4.61 D (range 0.00 D to , 14.88 D) were analysed. Measurements of ACD between the corneal epithelium and the anterior surface of the crystalline lens, obtained using the Pentacam, Orbscan IIz and IOLMaster, were compared. The relationships between SE and ACD measurements obtained with different devices were also investigated. The results were analysed using Bland,Altman analyses, single-sample t -test and Pearson's correlation test. Results:, Orbscan ACD measurements were an average of 0.05 mm less than Pentacam measurements (p = 0.01). IOLMaster measurements were an average of 0.06 mm less than Orbscan measurements (p < 0.001). None of the ACD values measured by any of the devices were correlated with increasing SE (p > 0.05 for all). There was a weak positive correlation between SE and the difference in ACD measurements with Pentacam and Orbscan (p = 0.04); however, the differences between Pentacam and IOLMaster ACD measurements and Orbscan and IOLMaster ACD measurements seemed to be independent of SE (p = 0.17 and p = 0.54, respectively). Conclusions:, The ACD in clinically normal eyes is measured differently by various non-ultrasonic devices. However, the observed mean error between these modalities is too small to create any noticeable difference in refractive outcome. No significant relationship was found between SE and ACD measurements obtained by Pentacam, Orbscan or IOLMaster. [source] Quality of thawed deepwater pink shrimp (Parapenaeus longirostris) treated with melanosis-inhibiting formulations during chilled storageINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 9 2007Maria Elvira López-Caballero Summary This work investigates how the treatment of thawed deepwater pink shrimp (Parapenaeus longirostris) with several melanosis-inhibiting formulations, affects the quality of the shrimp during chilled storage. Formulations were as follows: a formulation containing 4-hexylresorcinol (0.1 and 0.05%), in combination with organic acids and chelating agents, a commercial formula based on sulphites, and a mixture of gluconic acid and commercial sulphites. No noticeable differences were observed for both trimethylamine and total volatile bases during chilled storage. pH evolution was irrespective of the treatment condition. Microbial load enlarged after the sixth day of chilled storage. Higher total bacteria counts were associated with the control and sulphite treatment conditions, while lactic acid bacteria growth seemed to be favoured under formulations based on 4-hexylresorcinol. The appearance of melanosis occurred more rapidly in control shrimp or in shrimp treated with commercial sulphites. 4-hexylresorcinol formulations preserved the quality of thawed shrimp and could replace traditional sulphites. [source] Comparison of solubility of gases and vapours in wet and dry alcohols, especially octan-1-olJOURNAL OF PHYSICAL ORGANIC CHEMISTRY, Issue 10 2008Michael H. Abraham Abstract Equations for the solubility of gases and vapours into dry alcohols from methanol to decan-1-ol and into water-saturated alcohols from butan-1-ol to decan-1-ol have been compared through the use of the Abraham solvation equation. It is shown that there are noticeable differences in solvation into the dry and wet alcohols, and that these differences become larger as the alcohols become smaller and take up more water. The two main factors that lead to the differences in solvation are the solute hydrogen-bond basicity, B, and solute size, L. Increase in solute hydrogen-bond basicity favours the wet alcohols and increase in solute size favours the dry alcohols. Solute hydrogen-bond acidity plays no part, because the hydrogen-bond basicity of water, wet alcohols and dry alcohols is almost the same. Copyright © 2008 John Wiley & Sons, Ltd. [source] Effect of the challenger experience on elementary children's attitudes to scienceJOURNAL OF RESEARCH IN SCIENCE TEACHING, Issue 10 2002Tina Jarvis This research explored how the Challenger experience influenced over 655 elementary boys' and girls' general attitudes to science and space during the 5 months after their visit by examining their responses to four different attitude scales. These were administered to the 10- to 11-year-olds immediately before and after the Challenger experience as well as 2 and 5 months later. Knowledge tests were also administered before and after the visit. A sample of children completed an existing measure of anxiety. Although there were mainly positive outcomes immediately after the Challenger experience, there were some negative effects. There were also noticeable differences between boys and girls. Some 24% of pupils were inspired to become scientists. There was also less fear of space travel with a greater appreciation of the use of science to protect the planet after the visit. Most girls improved and maintained their attitudes toward science in society. A sizeable number of pupils were relatively unaffected by the experience and there was a significant negative effect on a small group of anxious girls. There are indications that previsit preparation and careful choice of roles during the simulation are important. © 2002 Wiley Periodicals, Inc. J Res Sci Teach 39: 979,1000, 2002 [source] Ruminal degradation of mountain pastures infested by Euphorbia polygalifolia in cattle and sheep: effect of previous grazing in invaded areasJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 13 2006Manuel J Mora Abstract Six cows and eight ewes were distributed in four paddocks according to a factorial design, 2 species (cattle vs sheep) × 2 grazing managements (grazing in pastures invaded vs non-invaded by Euphorbia polygalifolia), to study the ability of sheep and cattle to ruminally degrade mountain pastures containing E. polygalifolia, as well as the influence of previous grazing in invaded areas. After a period of 17 days, rumen fluids were collected and used as microbial inoculum to examine in vitro fermentation rates and ruminal parameters of infested and non-infested pastures. Results on parameters of gas production, extent of degradation, ammonia concentration and volatile fatty acid production of infested pastures indicate a better fermentation of this substrate in sheep than in cattle. The absence of noticeable differences when the pasture without this species of spurge was incubated suggests that most variation between ruminant species can be attributed to the presence of E. polygalifolia. The positive effect of previous grazing in invaded areas on rates of gas production, extent of degradation and ammonia concentration supports the hypothesis that the ability to degrade infested pastures may be enhanced by previous consumption, probably through an adaptation of the rumen microbiota. Copyright © 2006 Society of Chemical Industry [source] Ecological implications of biomass and morphotype variations of bacterioplankton: an example in a coastal zone of the Northern Adriatic Sea (Mediterranean)MARINE ECOLOGY, Issue 2 2005Rosabruna La Ferla Abstract This study had the objective of quantifying the variability in abundance, cell volume, morphology and C content of a natural bacterioplankton community in a coastal zone of the North Adriatic Sea during two periods (February and June) of two consequent years (1996 and 1997). We used epifluorescence microscopy with Acridine Orange staining procedures and a microphotographic technique. Low variability in bacterial abundance (range 0.3,3.1 × 105 cells ml,1) occurred between summer and winter periods. Conversely, the cell volume and the calculated carbon content changed greatly with warm and cold periods (ranges: 0.015,0.303 ,m3 and 5.83,42.17 fg C cell,1, respectively). Elongated bacteria were dominant while coccoid cells prevailed only in February 1997. Biomass showed high variability (range 0.12,10.21 ,g C l,1) whilst the abundance did not show noticeable differences among the sampling periods. As a consequence, quantification of bacterial biomass based solely on cell abundance must be considered with caution because the true biomass could depend on variability in cell volumes and morphotypes. [source] The clay mineralogy of sediments related to the marine Mjølnir impact craterMETEORITICS & PLANETARY SCIENCE, Issue 10 2003Henning DYPVIK It was formed about 142 ± 2.6 Myr ago by the impact of a 1,2 km asteroid into the shallow shelf clays of the Hekkingen Formation and the underlying Triassic to Jurassic sedimentary strata. A core recovered from the central high within the crater contains slump and avalanche deposits from the collapse of the transient crater and central high. These beds are overlain by gravity flow conglomerates, with laminated shales and marls on top. Here, impact and post-impact deposits in this core are studied with focus on clay mineralogy obtained from XRD decomposition and simulation analysis methods. The clay-sized fractions are dominated by kaolinite, illite, mixed-layered clay minerals and quartz. Detailed analyses showed rather similar composition throughout the core, but some noticeable differences were detected, including varying crystal size of kaolinite and different types of illites and illite/smectite. These minerals may have been formed by diagenetic changes in the more porous/fractured beds in the crater compared to time-equivalent beds outside the crater rim. Long-term post-impact changes in clay mineralogy are assumed to have been minor, due to the shallow burial depth and minor thermal influence from impact-heated target rocks. Instead, the clay mineral assemblages, especially the abundance of chlorite, reflect the impact and post-impact reworking of older material. Previously, an ejecta layer (the Sindre Bed) was recognized in a nearby well outside the crater, represented by an increase in smectite-rich clay minerals, genetically equivalent to the smectite occurring in proximal ejecta deposits of the Chicxulub crater. Such alteration products from impact glasses were not detected in this study, indicating that little, if any, impact glass was deposited within the upper part of the crater fill. Crater-fill deposits inherited their mineral composition from Triassic and Jurassic sediments underlying the impact site. [source] Inequality for Wage Earners and Self-Employed: Evidence from Panel Data,OXFORD BULLETIN OF ECONOMICS & STATISTICS, Issue 4 2009Pedro Albarran Abstract In this paper we highlight the importance of analysing the evolution of income inequality separately for employees and self-employed workers. Using Spanish panel data on income and consumption for the period 1987,96, we find noticeable differences across these groups in the evolution of income inequality, and in the relative importance of the transitory and permanent components of income variance. The evolution of inequality is mainly explained by movements in the transitory component for the self-employed and by the permanent component for the employees. Our results suggest that different policies should be implemented for each group. [source] Determinants of Japanese Yen interest rate swap spreads: Evidence from a smooth transition vector autoregressive modelTHE JOURNAL OF FUTURES MARKETS, Issue 1 2008Ying Huang This study investigates the determinants of variations in the yield spreads between Japanese yen interest rate swaps and Japan government bonds for a period from 1997 to 2005. A smooth transition vector autoregressive (STVAR) model and generalized impulse response functions are used to analyze the impact of various economic shocks on swap spreads. The volatility based on a GARCH (generalized autoregressive conditional heteroskedasticity) model of the government bond rate is identified as the transition variable that controls the smooth transition from a high volatility regime to a low volatility regime. The break point of the regime shift occurs around the end of the Japanese banking crisis. The impact of economic shocks on swap spreads varies across the maturity of swap spreads as well as regimes. Overall, swap spreads are more responsive to the economic shocks in the high volatility regime. Moreover, a volatility shock has profound effects on shorter maturity spreads, whereas the term structure shock plays an important role in impacting longer maturity spreads. Results of this study also show noticeable differences between the nonlinear and linear impulse response functions. © 2008 Wiley Periodicals, Inc. Jrl Fut Mark 28:82,107, 2008 [source] Data processing issues in large-area GPR surveys: correcting trace misalignments, edge discontinuities and stripingARCHAEOLOGICAL PROSPECTION, Issue 2 2008Eileen G. Ernenwein Abstract Ground-penetrating radar (GPR) lags behind other archaeogeophysical methods in terms of speed, efficiency and ability to produce clean site-wide composites owing to complex and time-consuming data processing requirements. Two North American case studies illustrate problems that occur when survey is conducted over long and short periods of time. Some GPR defects have been blamed on differential solar heating of antennae and battery power levels but we show these effects to be negligible. Major problems include gradual changes over time in ground moisture and low-level background noise, which can create discontinuities between adjacent survey blocks when data are collected at different times. These problems are often remedied by globally aligning traces using a stable trace position. Variations in ground moisture through time also cause differences in reflection amplitudes, necessitating different range gain curves to match amplitudes between survey blocks. In some cases changes in ground moisture cause noticeable differences in velocity between survey blocks requiring time-scales to be converted to depths to correctly match the data. These problems must be remedied before horizontal slicing can be considered. Subsequent image processing may also be necessary to generate a seamless mosaic and eliminate striping artefacts commonly seen in slice maps. The latter are probably caused by antenna lift and tilt and can be removed by a de-striping algorithm that uses a one-dimensional low-pass filter to characterize stripes followed by their subtraction from the data. Copyright © 2008 John Wiley & Sons, Ltd. [source] Mobile phone base station-emitted radiation does not induce phosphorylation of Hsp27BIOELECTROMAGNETICS, Issue 2 2007H. Hirose Abstract An in vitro study focusing on the effects of low-level radiofrequency (RF) fields from mobile radio base stations employing the International Mobile Telecommunication 2000 (IMT-2000) cellular system was conducted to test the hypothesis that modulated RF fields act to induce phosphorylation and overexpression of heat shock protein hsp27. First, we evaluated the responses of human cells to microwave exposure at a specific absorption rate (SAR) of 80 mW/kg, which corresponds to the limit of the average whole-body SAR for general public exposure defined as a basic restriction in the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines. Second, we investigated whether continuous wave (CW) and Wideband Code Division Multiple Access (W-CDMA) modulated signal RF fields at 2.1425 GHz induced activation or gene expression of hsp27 and other heat shock proteins (hsps). Human glioblastoma A172 cells were exposed to W-CDMA radiation at SARs of 80 and 800 mW/kg for 2,48 h, and CW radiation at 80 mW/kg for 24 h. Human IMR-90 fibroblasts from fetal lungs were exposed to W-CDMA at 80 and 800 mW/kg for 2 or 28 h, and CW at 80 mW/kg for 28 h. Under the RF field exposure conditions described above, no significant differences in the expression levels of phosphorylated hsp27 at serine 82 (hsp27[pS82]) were observed between the test groups exposed to W-CDMA or CW signal and the sham-exposed negative controls, as evaluated immediately after the exposure periods by bead-based multiplex assays. Moreover, no noticeable differences in the gene expression of hsps were observed between the test groups and the negative controls by DNA Chip analysis. Our results confirm that exposure to low-level RF field up to 800 mW/kg does not induce phosphorylation of hsp27 or expression of hsp gene family. Bioelectromagnetics © 2006 Wiley-Liss, Inc. [source] Degradation patterns of tetracycline antibiotics in reverse micelles and waterBIOMEDICAL CHROMATOGRAPHY, Issue 11 2006Hongkee Sah Abstract The objective of this study was to determine the chemical stability of tetracycline and oxytetracycline hydro-chlorides in reverse micelles. Their reverse micellar solutions were prepared using cetyltrimethylammonium bromide, water and ethyl formate. The aqueous solutions of the tetracycline antibiotics were also prepared for comparison. The reverse micellar and aqueous solutions were stored at 37C. Samples were analyzed by high performance liquid chromatography. When evaluation was performed on an aqueous tetracycline HCl solution, its half-life was estimated to be 329 h. Its chemical stability was not improved after being dissolved in the reverse micelles, and a similar half-life of 330 h was observed. However, there were noticeable differences between the two systems in terms of degradation kinetics and degradation byproducts. On the other hand, oxytetracycline HCl was unstable in water so that its half-life was only 34 h. Very interestingly, pronounced improvement in stability was attained with the reverse micellar system: upon dissolving in the reverse micelles, its half-life was increased to 2402 h. There were also marked differences in degradation patterns and mechanisms of oxytetracycline HCl in water and the reverse micelles. Our study indicates that the reverse micellar system has potential applications in solubilizing and stabilizing oxytetracycline HCl, thereby contributing to the development of its dosage forms. Copyright © 2006 John Wiley & Sons, Ltd. [source] Corporate environmental reporting: what's in a metric?BUSINESS STRATEGY AND THE ENVIRONMENT, Issue 2 2003R. Scott Marshall Assistant Professor of Management Although there has been increased attention to corporate environmental reports (CERs), there has yet to be a close examination of the metrics used in these reports. Metrics do not address the content of CERs, but, perhaps more importantly, metrics provide the means for conveying the content. In this paper, we analyze metrics used in 79 corporations' recent CER reports. We define and use an 'environmental sustainability' lens, and apply two environmental metrics taxonomies to CER metrics. We also consider the implications of key internal and external firm factors on CER metrics. Our findings suggest that (i) firms' compliance with ISO 14001 increases the presence of future oriented metrics, (ii) a majority of CER content uses lagging metrics with descriptive and operational performance information, (iii) larger firms are more likely than smaller firms to use future oriented metrics and (iv) there are noticeable differences across countries/regions in terms of CER metrics. Several important issues seem evident from the study. First, the metrics most commonly used in CERs provide little information about future performance. Second, the majority of metrics describe operations performance rather than environmental impact. Third, even though the sample was chosen based on a priori indicators of corporate environmental awareness, only about half of the companies sampled had a CER available. Copyright © 2003 John Wiley & Sons, Ltd. and ERP Environment [source] Liquid-Phase Hydrogenation of Unsaturated Aldehydes: Enhancing Selectivity of Multiwalled Carbon Nanotube-Supported Catalysts by Thermal ActivationCHEMCATCHEM, Issue 2 2010Bruno Abstract Platinum and iridium organometallic precursors are used to prepare nanosized, thermally stable multiwalled carbon nanotube-supported catalysts. The materials are characterized by N2 adsorption at 77,K, temperature-programmed desorption coupled with mass spectrometry, H2 chemisorption, transmission electron microscopy and thermogravimetric analysis; they are tested in the selective hydrogenation of cinnamaldehyde to cinnamyl alcohol under mild conditions (363,K and 1,MPa). A thermal activation at 973,K is found to have a very positive effect over both activity and selectivity, leading to selectivities of approximately 70,%, at 50,% conversion, regardless of the active metal phase (Pt or Ir). Since no noticeable differences in the metal particle sizes are detected, the results are interpreted in light of an enhanced metal/support interaction. This effect, induced by the removal of oxygenated surface groups, is thought to change the adsorption mechanism of the cinnamaldehyde molecule. [source] | |||||||||||||||||||||||||