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Kinds of Air Terms modified by Air Selected AbstractsMeasuring remanence anisotropy of hematite in red beds: anisotropy of high-field isothermal remanence magnetization (hf-AIR)GEOPHYSICAL JOURNAL INTERNATIONAL, Issue 3 2009Dario Bilardello SUMMARY The potential of using high-field anisotropy of isothermal remanence magnetization (hf-AIR) measurements for determining the origin of natural remanent magnetization in red beds and for identifying and correcting possible red-bed inclination shallowing was investigated for specimens of the Carboniferous Shepody Formation of New Brunswick and Nova Scotia, Canada. The technique makes it possible for a typical paleomagnetic laboratory to measure the remanence anisotropy of high-coercivity hematite. High-field (hf) AIR was used in conjunction with 100 mT alternating field (af) and 120 °C thermal demagnetization to separate the contribution of hematite to the remanence anisotropy from that of magnetite/maghemite and goethite, respectively. A 5-T impulse DC magnetic field was used for the hf-AIR to reset the magnetic moment of high-coercivity hematite so that demagnetization between AIR orientations was not necessary. The ability of a 5-T field to reset the magnetization was tested by generating an isothermal remanent magnetization acquisition curve for hematite by using impulse DC magnetic fields up to 5 T in one orientation and followed by applying a field in the opposite direction at each step. Each field application was treated by 120 °C heating and 100 mT af demagnetization before measurement. At 5 T, the difference between the magnetizations applied in opposite directions disappeared indicating that no magnetic memory persisted at this field strength. We performed a validity and reproducibility test of our hf-AIR measurement technique by measuring three specimens multiple times along two orthogonal coordinate systems. The method yielded highly reproducible results and, on rotating the specimen's coordinates, the fabric rotated by 90° as expected, showing that it is not an artifact of the technique. We also measured hf-AIR on samples that had previously been chemically demagnetized in 3N HCl to remove the secondary, chemically grown pigmentary hematite. The hf-AIR fabric of leached samples is similar to that of untreated samples, but shows a better-defined magnetic lineation and imbrication. We interpret the fabric observed for the Shepody Formation to be a compactional fabric that has been reoriented by strain during folding following a flexural-slip model. [source] QUALITY OF FROZEN SHRIMP THAWED BY RECIRCULATING AIR VERSUS WATER IMMERSIONJOURNAL OF FOOD QUALITY, Issue 1 2003C. S. LIN ABSTRACT The quality of shrimp thawed using a constant temperature thawing chamber compared with running water was studied. Shrimp thawed in room temperature air was used as the control. Shrimp thawed using the thawing chamber had lower drip loss, higher yield and moisture content than shrimp thawed by running water. However, the differences were not statistically significant. There were also no significant differences in press juice and shear force between control and shrimp thawed using either thawing method. Shrimp thawed using the thawing chamber had lower aerobic bacterial counts than either control or shrimp thawed using running water. Shrimp thawed using the thawing chamber did not exceed ,1C throughout the thawing experiment, and microbial growth during thawing was also avoided. Results indicated that the thawing chamber has potential for the foodservice industry to produce uniformly thawed products under sanitary conditions. [source] Assessment of Relationships between Sensory and Instrumental Quality of Controlled-atmosphere-stored ,Fuji' Apples by Multivariate AnalysisJOURNAL OF FOOD SCIENCE, Issue 9 2004G. Echeverría ABSTRACT: Physicochemical parameters, sensory attributes, and total aroma emission of ,Fuji' apples (Malus×domestica Borkh.) were studied in relation to storage conditions, storage duration, and shelf life period. Commercially ripe fruit were analyzed after 3, 5, and 7 mo of cold storage in normal atmosphere (AIR) (210 L/m3 O2+ 0.3 L/m3 CO2) or under 3 different controlled atmosphere (CA) treatments (10 L/m3 O2+ 10 L/m3 CO2, 20 L/m3 O2+ 20 L/m3 CO2, or 10 L/m3 O2+ 30 L/m3 CO2), after which apples were kept at 20 °C for 1, 5, and 10 d. Data were subjected to partial least square regression (PLSR) analysis. Physicochemical parameters were well preserved throughout storage, especially in CA-stored apples; however, these apples showed lower total aroma emission. Sensory acceptability was also higher for CA-stored fruit after 7 mo of storage, whereas no significant differences were found for shorter storage periods. Accordingly, greater scores in sensory firmness, sensory flavor, sensory acidity, and appearance were observed for fruit stored in 10 L/m3 O2+ 10 L/m3 CO2 after long storage. Two PLSR models were established, 1 for relating physicochemical parameters to overall acceptability, and another for assessing the correlation between sensory acidity and instrumentally measured titratable acidity. The 1st PLSR model indicated that soluble solids concentration, titratable acidity, flesh firmness, and background color of the shaded side have a positive influence on acceptability. The 2nd model indicated that sensory acidity also showed an excellent correlation to instrumentally measured titratable acidity. [source] Synthesis of 32P-labeled intermediates on the purine biosynthetic pathwayJOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 13 2002Ryan A. Mehl Abstract A fast and efficient route to 32P-labeled intermediates on the purine biosynthetic pathway is described. Adenosine kinase catalyzes the phosphorylation of 5-aminoimidazole-4-carboxamide ribonucleoside (AICARs) to give [32P]-5-aminoimidazole-4-carboxamide ribonucleotide (AICAR). This was then hydrolyzed to [32P]-4-carboxy-5-aminoimidazole ribonucleotide (CAIR). Treatment of CAIR with N5-CAIR mutase gave [32P]-5-aminoimidazole ribonucleotide (AIR) in milligram quantities. Copyright © 2002 John Wiley & Sons, Ltd. [source] Safety and quality of plastic food contact materials.PACKAGING TECHNOLOGY AND SCIENCE, Issue 5 2003Optimization of extraction time, based on arithmetic rules derived from mathematical description of diffusion., extraction yield Abstract Migration of packaging constituents into food may raise concerns about food safety. This paper describes the conclusions of a EU research project (AIR 941025), aiming to facilitate the introduction of migration control into good manufacturing practice and into enforcement policies. The first part describes a re-evaluation of analytical approaches to extract and identify potential migrants released by plastic materials, viz. comparison of analytical methods, choice of extraction solvents and of fat simulants. Here we focus on the extraction time needed to achieve a given extraction yield. By correlating these parameters with simple and practical equations, it is possible to design alternative tests for control of compliance of packaging plastics. Using a reference experiment (where there is good agreement between experimental and calculated kinetic curves), it is possible to calculate the percentage of extraction which can be achieved in a given time, or the time necessary to reach a target extraction level for other polymer/solvent combinations. A global control scheme is proposed, which indicates whether and when calculation and testing should be applied. Guidelines are proposed, and can be adapted to both industrial control and to enforcement laboratories. Copyright © 2003 John Wiley & Sons, Ltd. [source] Risk factors for severe infections in patients with rheumatoid arthritis treated with rituximab in the autoimmunity and rituximab registryARTHRITIS & RHEUMATISM, Issue 9 2010J.-E. Gottenberg Objective The risk of severe infection is a crucial factor in the assessment of the short-term risk:benefit ratio of biologic drugs in rheumatoid arthritis (RA). There is no increase in severe infections in RA patients treated with rituximab (RTX) in controlled trials, but this has not yet been assessed in daily practice. We undertook this study to investigate the occurrence of and risk factors for severe infections in off-trial patients using data from the AutoImmunity and Rituximab (AIR) registry. Methods The AIR registry was set up by the French Society of Rheumatology. The charts of patients with severe infections were reviewed. Results Of the enrolled patients, 1,303 had at least 1 followup visit at 3 months or later, with a mean ± SD followup period of 1.2 ± 0.8 years (1,629 patient-years). Eighty-two severe infections occurred in 78 patients (5.0 severe infections per 100 patient-years), half of them in the 3 months following the last RTX infusion. Multivariate analysis showed that chronic lung disease and/or cardiac insufficiency (odds ratio 3.0 [95% confidence interval 1.3,7.3], P = 0.01), extraarticular involvement (odds ratio 2.9 [95% confidence interval 1.3,6.7], P = 0.009), and low IgG level (<6 gm/liter) before initiation of RTX treatment (odds ratio 4.9 [95% confidence interval 1.6,15.2], P = 0.005) were significantly associated with increased risk of a severe infection. Conclusion The rate of severe infections in current practice is similar to that reported in clinical trials. The risk factors for severe infections include chronic lung and/or cardiac disease, extraarticular involvement, and low IgG before RTX treatment. This suggests that serum IgG should be checked and the risk:benefit ratio of RTX discussed for patients found to have low levels of IgG. [source] Safety and efficacy of rituximab in systemic lupus erythematosus: Results from 136 patients from the French autoimmunity and rituximab registryARTHRITIS & RHEUMATISM, Issue 8 2010Benjamin Terrier Objective A number of open-label studies have suggested the potential benefit of rituximab (RTX) in systemic lupus erythematosus (SLE). However, in 2 recent randomized controlled trials (RCTs) of RTX, the primary end points were not met. We undertook this study to evaluate the safety and efficacy of RTX in off-trial patients with SLE seen in regular clinical practice. Methods We analyzed prospective data from the French AutoImmunity and Rituximab (AIR) registry, which includes data on patients with autoimmune disorders treated with RTX. Results One hundred thirty-six patients received treatment for SLE. The mean ± SD score on the Safety of Estrogens in Lupus Erythematosus: National Assessment (SELENA) version of the SLE Disease Activity Index (SLEDAI) was 11.3 ± 8.9 at baseline. Severe infections were noted in 12 patients (9%), corresponding to a rate of 6.6/100 patient-years. Most severe infections occurred within the first 3 months after the last RTX infusion. Five patients died, due to severe infection (n = 3) or refractory autoimmune disease (n = 2). Overall response was observed in 80 of 113 patients (71%) by the SELENA,SLEDAI assessment. Efficacy did not differ significantly between patients receiving RTX monotherapy and those receiving concomitant immunosuppressive agents (who had higher baseline disease activity). Articular, cutaneous, renal, and hematologic improvements were noted in 72%, 70%, 74%, and 88% of patients, respectively. Among responders, 41% experienced a relapse of disease, with a response in 91% after retreatment with RTX. Conclusion Data from the AIR registry show a satisfactory tolerance profile and clinical efficacy of RTX in patients with SLE. The contrasting results with those from recent RCTs leave open the question of the therapeutic use of RTX in SLE. Additional controlled studies with new designs are needed to define the place of RTX in the therapeutic arsenal for SLE. [source] Rosiglitazone improves insulin sensitivity and glucose tolerance in subjects with impaired glucose toleranceCLINICAL ENDOCRINOLOGY, Issue 1 2005Yi-Jen Hung Summary Objective, This study was designed to evaluate the effects of rosiglitazone (ROS) on insulin sensitivity, ,-cell function, and glycaemic response to glucose challenge and meal in subjects with impaired glucose tolerance (IGT). Methods, Thirty patients with IGT (ages between 30 and 75 years and BMI (body mass index) , 27 kg/m2) were randomly assigned to receive either placebo (n = 15) or ROS (4 mg/day) (n = 15). All participants underwent a 75-g oral glucose tolerance test (OGTT), meal test, and frequently sampled intravenous glucose tolerance test (FSIGT) before and after the 12-week treatment. Results, After 12 weeks of ROS treatment, there were significant increases in total cholesterol (TC) (4·25 ± 0·22 vs 4·80 ± 0·17 mmol/l, P < 0·001), high-density lipoprotein cholesterol (HDL-C) (1·25 ± 0·07 vs 1·43 ± 0·06 mmol/l, P < 0·05), and low-density lipoprotein cholesterol (LDL-C) (2·70 ± 0·15 vs 3·37 ± 0·17 mmol/l, P < 0·05) without changes in triglyceride concentration, TC/HDL-C and LDL-C/HDL-C ratio. Although the acute insulin response (AIR) to intravenous glucose and disposition index (measured as the ability of pancreatic ,-cell compensation in the presence of insulin resistance) remained unchanged, the insulin sensitivity (SI) and glucose effectiveness (SG) were remarkably elevated (0·38 ± 0·06 vs 0·54 ± 0·09 × 10,5 min,1/pmol, P < 0·05; 0·017 ± 0·002 vs 0·021 ± 0·001 min,1, P < 0·05, respectively) in the ROS group. The glucose, insulin, and c-peptide areas under curve (AUC) in response to OGTT and the glucose and insulin AUC during meal were significantly ameliorated in the ROS group. Five out of 15 (33%) and two out of 15 (13%) subjects treated with ROS and placebo, respectively, reversed to normal response during OGTT (P < 0·05). Conclusion, Rosiglitazone treatment significantly improved insulin resistance and reduced postchallenge glucose and insulin concentrations in patients with impaired glucose tolerance without remarkable effects on ,-cell secretory function. [source] Radiative transfer validation study from the European Aqua Thermodynamic ExperimentTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 639 2009Stuart M. Newman Abstract The European AQUA Thermodynamic Experiment (EAQUATE) brought together collocated hyperspectral measurements from the Atmospheric Infrared Sounder (AIRS) on NASA's Aqua satellite, as well as three airborne interferometers operating in the troposphere and stratosphere. Simultaneous observations of temperature, water vapour and trace gases have been used to constrain the atmospheric state, for validation of radiometric accuracy and radiative transfer modelling. The close agreement of observations with model spectra, in the 800,1200 cm,1 region, indicates that the accuracy of modelling AIRS spectra is sufficient for beneficial use of the data in operational weather forecasting. The variability of atmospheric water vapour was found to be a fundamental constraint in the modelling of the 1400,1600 cm,1 region, emphasising the requirement for a high density of observations in future validation campaigns. Copyright © Royal Meteorological Society and Crown Copyright, 2009. [source] Assimilation of IASI at the Met Office and assessment of its impact through observing system experimentsTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 639 2009F. Hilton Abstract Observations from the Infrared Atmospheric Sounding Interferometer (IASI), onboard EUMETSAT's MetOp satellite, have been assimilated at the Met Office in global and regional numerical weather-prediction systems since 27 November 2007. Pre-operational trials of IASI assimilation in the global model during the summer of 2007 delivered a positive impact on forecasts approximately twice as large as that shown by the Atmospheric InfraRed Sounder (AIRS) on the EOS-Aqua satellite. A series of observing system experiments confirmed the relative performance of IASI and AIRS, and showed that impact from IASI is equivalent to a single Advanced Microwave Sounding Unit-A (AMSU-A) combined with a single Microwave Humidity Sounder (MHS). The results of an IASI assimilation trial for the winter of 2007 were consistent with those of the summer trial, although the impact was slightly lower overall. The assessment of impact is strongly dependent on the variables and methods chosen for verification: assimilation trials with the regional model showed similar improvements to the large-scale fields (e.g. mean-sea-level pressure and geopotential height) as seen in the global model, but no forecast impact was seen for variables such as visibility and rain-rate. © Crown Copyright 2009. Reproduced with the permission of the Controller of HMSO. Published by John Wiley & Sons, Ltd. [source] Effects of data selection and error specification on the assimilation of AIRS data,THE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 622 2007J. Joiner Abstract The Atmospheric InfraRed Sounder (AIRS), flying aboard NASA's Aqua satellite with the Advanced Microwave Sounding Unit-A (AMSU-A) and four other instruments, has been providing data for use in numerical weather prediction and data assimilation systems for over three years. The full AIRS data set is currently not transmitted in near-real-time to the prediction/assimilation centres. Instead, data sets with reduced spatial and spectral information are produced and made available within three hours of the observation time. In this paper, we evaluate the use of different channel selections and error specifications. We achieve significant positive impact from the Aqua AIRS/AMSU-A combination during our experimental time period of January 2003. The best results are obtained using a set of 156 channels that do not include any in the H2O band between 1080 and 2100 cm,1. The H2O band channels have a large influence on both temperature and humidity analyses. If observation and background errors are not properly specified, the partitioning of temperature and humidity information from these channels will not be correct, and this can lead to a degradation in forecast skill. Therefore, we suggest that it is important to focus on background error specification in order to maximize the impact from AIRS and similar instruments. In addition, we find that changing the specified channel errors has a significant effect on the amount of data that enters the analysis as a result of quality control thresholds that are related to the errors. However, moderate changes to the channel errors do not significantly impact forecast skill with the 156 channel set. We also examine the effects of different types of spatial data reduction on assimilated data sets and NWP forecast skill. Whether we pick the centre or the warmest AIRS pixel in a 3 × 3 array affects the amount of data ingested by the analysis but does not have a statistically significant impact on the forecast skill. Copyright © Published in 2007 by John Wiley & Sons, Ltd. [source] Use of the MODIS imager to help deal with AIRS cloudy radiancesTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 610 2005Mohamed Dahoui Abstract The assimilation of the Atmospheric InfraRed Sounder (AIRS) data is expected to improve the quality of NWP products. Currently, operational use of such data is limited to the cloud-free pixels or to the channels far above the clouds for cloudy pixels. This paper focuses on the validation of various cloud-detection schemes applied to AIRS data. The clouds are detected and characterized, in cloud-top and cover, by using the NESDIS, ECMWF, CO2 -slicing and MLEV schemes. These four different AIRS cloud descriptions are evaluated by independent information retrieved with the Météo-France cloud mask applied to MODIS data and taken as our reference. The validation for a ten-day period over the North-east Atlantic is presented. The use of satellite cloudy radiances is a great challenge for numerical weather prediction. Work is in progress to assimilate such data by using enhanced observation operators dealing with clouds. In this work, we try to contribute to this effort by investigating the linearity assumption of an observation operator, with a simple diagnostic cloud scheme, for different cloud types. Copyright © 2005 Royal Meteorological Society [source] An error analysis of radiance and suboptimal retrieval assimilationTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 565 2000J. Joiner Abstract One of the outstanding problems in data assimilation has been, and continues to be, how best to utilize satellite data while balancing the trade-off between accuracy and computational cost. A number of weather-prediction centres have recently achieved remarkable success in improving their forecast skill by changing the method in which satellite data are assimilated into the forecast model from the traditional approach of assimilating retrieved products to the direct assimilation of radiances in a variational framework. Although there are. clear theoretical advantages to the direct radiance-assimilation approach, it is not obvious at all to what extent the improvements that have been obtained so far can be attributed to the change in methodology or to various technical aspects of the implementation. The central question we address here is: how much improvement can we expect from assimilating radiances rather than retrievals, all other things being equal? We compare the two approaches in a simplified theoretical framework. Direct radiance analysis is optimal in this idealized context, while the traditional method of assimilating retrievals is suboptimal because it ignores the cross-covariances between background errors and retrieval errors. We show that interactive retrieval analysis (where the same background used for assimilation is also used in the retrieval step) is equivalent to direct assimilation of radiances with suboptimal analysis weights. We illustrate and extend these theoretical arguments with several one-dimensional analysis experiments, where we estimate vertical atmospheric profiles using simulated data from temperature sounding channels of both the High-resolution InfraRed Sounder 2 (HIRS2) and the future Atmospheric InfraRed Sounder (AIRS). In the case of non-interactive retrievals the results depend very much on the quality of the background information used for the retrieval step. In all cases, the impact of the choice of analysis method is dwarfed by the effect of changing some of the experimental parameters that control the simulated error characteristics of the data and the retrieval background. [source] Predicting intra-urban variation in air pollution concentrations with complex spatio-temporal dependencies,ENVIRONMETRICS, Issue 6 2010Adam A. Szpiro Abstract We describe a methodology for assigning individual estimates of long-term average air pollution concentrations that accounts for a complex spatio-temporal correlation structure and can accommodate spatio-temporally misaligned observations. This methodology has been developed as part of the Multi-Ethnic Study of Atherosclerosis and Air Pollution (MESA Air), a prospective cohort study funded by the US EPA to investigate the relationship between chronic exposure to air pollution and cardiovascular disease. Our hierarchical model decomposes the space--time field into a "mean" that includes dependence on covariates and spatially varying seasonal and long-term trends and a "residual" that accounts for spatially correlated deviations from the mean model. The model accommodates complex spatio-temporal patterns by characterizing the temporal trend at each location as a linear combination of empirically derived temporal basis functions, and embedding the spatial fields of coefficients for the basis functions in separate linear regression models with spatially correlated residuals (universal kriging). This approach allows us to implement a scalable single-stage estimation procedure that easily accommodates a significant number of missing observations at some monitoring locations. We apply the model to predict long-term average concentrations of oxides of nitrogen (NOx) from 2005 to 2007 in the Los Angeles area, based on data from 18 EPA Air Quality System regulatory monitors. The cross-validated IR2 is 0.67. The MESA Air study is also collecting additional concentration data as part of a supplementary monitoring campaign. We describe the sampling plan and demonstrate in a simulation study that the additional data will contribute to improved predictions of long-term average concentrations. Copyright © 2009 John Wiley & Sons, Ltd. [source] Nickel Complexes of N/O -Functionalized N-Heterocyclic Carbenes as Precatalysts for Michael Reactions in Air at Room Temperature Under the Much Preferred Base-Free ConditionsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 13 2009Sriparna Ray Abstract A series of several new nickel precatalysts supported overN/O -functionalized N-heterocyclic carbenes (NHC) for the Michael reactions of ,-dicarbonyl, ,-keto ester, ,-diester, and ,-cyano ester compounds with ,,,-unsaturated carbonyl compounds in air at ambient temperature under the much preferred base-free conditions are reported. Specifically, the nickel complexes, [1-(R1 -aminocarbonylmethyl)-3-R2 -imidazol-2-ylidene]2Ni [R1 = 2-C6H4(OMe); R2 = Me (1b), iPr (2b), CH2Ph (3b) and R1 = 2-CH2C4H3O; R2 = Me (4b), CH2Ph (5b)] carried out the highly convenient base-free Michael addition of the activated C,H compounds across ,,,-unsaturated carbonyl compounds in air at room temperature. The complexes 1b,5b were synthesized by the direct reaction of the respective imidazolium chloride salt with NiCl2·6H2O in CH3CN in the presence of K2CO3 as a base. The exceptional stability of 1b,5b has been attributed to the deeply buried nickel,NHC ,-bonding molecular orbitals as evidenced from the density functional theory (DFT) studies. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Fluoride-Free Hiyama and Copper- and Amine-Free Sonogashira Coupling in Air in a Mixed Aqueous Medium by a Series of PEPPSI-Themed Precatalysts,EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 12 2009Chandrakanta Dash Abstract A new series of robust, user-friendly, and highly active PEPPSI-themed (pyridine-enhanced precatalyst preparation, stabilization and initiation) (NHC)PdX2(pyridine)-type (X = Cl, Br) precatalysts of C4,C5 saturated imidazole- (1,4) and triazole-based (5 and 6) N-heterocyclic carbenes for the Hiyama and Sonogashira couplings under amenable conditions are reported. Specifically 1,6 efficiently catalyze the fluoride-free Hiyama coupling of aryl halides with PhSi(OMe)3 and CH2=CHSi(OMe)3 in air in the presence of NaOH as a base in a mixed aqueous medium (dioxane/H2O, 2:1 v/v). Along the same lines, these 1,6 precatalysts also promote the Cu-free and amine-free Sonogashira coupling of aryl bromides and iodides with phenylacetylene in air and in a mixed aqueous medium (DMF/H2O, 3/1 v/v). The complexes 1,6 were synthesized by the direct reaction of the respective imidazolinium and triazolium halide salts with PdCl2 in pyridine in the presence of K2CO3 as a base. DFT studies on the catalytically relevant palladium(0) (NHC)Pd(pyridine) precursors 1a,6a reveal significant donation from the N-heterocyclic carbene lone pair onto the unfilled ,* orbital of the trans Pd,pyridine bond. This weakens the Pd-bound "throwaway" pyridine ligand, and its dissociation marks the initiation of the catalytic cycle.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] U.S. Spanish on the Air: Good Waves for the Classroom?FOREIGN LANGUAGE ANNALS, Issue 5 2001Carmen Villegas Rogers EdD Using segments of programming taped from stations in eight US. states, the researchers compiled data on the presence of Anglicisms in commercials and announcements; commentaries and discussions; and news, weather, and traffic reporting. Possible reasons for the use of these Anglicisms and the effect that the phenomenon might have on the maintenance of Spanish within the Latino community are discussed, The authors suggest ways in which these samples of authentic speech might be used in the classroom to present not only the idealized speech of the so-called "educated native speaker," but also dynamic and current models of interlocutors from many nations, interacting effectively as they transmit and receive information in the language. [source] Response of soil surface CO2 flux in a boreal forest to ecosystem warmingGLOBAL CHANGE BIOLOGY, Issue 4 2008DUSTIN R. BRONSON Abstract Soil surface carbon dioxide (CO2) flux (RS) was measured for 2 years at the Boreal Soil and Air Warming Experiment site near Thompson, MB, Canada. The experimental design was a complete random block design that consisted of four replicate blocks, with each block containing a 15 m × 15 m control and heated plot. Black spruce [Picea mariana (Mill.) BSP] was the overstory species and Epilobium angustifolium was the dominant understory. Soil temperature was maintained (,5 °C) above the control soil temperature using electric cables inside water filled polyethylene tubing for each heated plot. Air inside a 7.3-m-diameter chamber, centered in the soil warming plot, contained approximately nine black spruce trees was heated ,5 °C above control ambient air temperature allowing for the testing of soil-only warming and soil+air warming. Soil surface CO2 flux (RS) was positively correlated (P < 0.0001) to soil temperature at 10 cm depth. Soil surface CO2 flux (RS) was 24% greater in the soil-only warming than the control in 2004, but was only 11% greater in 2005, while RS in the soil+air warming treatments was 31% less than the control in 2004 and 23% less in 2005. Live fine root mass (< 2 mm diameter) was less in the heated than control treatments in 2004 and statistically less (P < 0.01) in 2005. Similar root mass between the two heated treatments suggests that different heating methods (soil-only vs. soil+air warming) can affect the rate of decomposition. [source] Evaluation of soil saturation, soil chemistry, and early spring soil and air temperatures as risk factors in yellow-cedar declineGLOBAL CHANGE BIOLOGY, Issue 3 2006D. V. D'AMORE Abstract Yellow-cedar (Callitropsis nootkatensis (D. Don) Oerst.) is a valuable tree species that is experiencing a widespread decline and mortality in southeast Alaska. This study evaluated the relative importance of several potential risk factors associated with yellow-cedar decline: soil saturation, soil aluminum (Al) toxicity or calcium (Ca) deficiency, and air and soil temperature. Data were collected from permanent vegetation plots established in two low-elevation coastal forests exhibiting broad ranges of cedar mortality. Measurements of each risk factor were contrasted among classified forest zones to indicate if there were strong links with decline. Hydrology alone is weakly associated with yellow-cedar decline, but could have a predisposing role in the decline by creating exposed conditions because of reduced forest productivity. Yellow-cedar decline is not strongly associated with soil pH and extractable Al and Ca, but there appears to be Ca enrichment of surface soils by feedback from dead yellow-cedar foliage. Air and soil temperature factors are strongly associated with decline. Based on these results, an hypothesis is presented to explain the mechanism of tree injury where exposure-driven tree mortality is initiated in gaps created by soil saturation and then expands in gaps created by the tree-mortality itself. The exposure allows soils to warm in early spring causing premature dehardening in yellow-cedar trees and subsequent freezing injury during cold events. Yellow-cedars growing in the protection of shade or snow are not preconditioned by this warming, and thus not as susceptible to cold injury. Yellow-cedar decline appears to be associated with regional climate changes, but whether the cause of these changes is related to natural or human-induced climate shifts remains uncertain. Management implications, the possible role of climate, and recommended research are discussed. [source] Measurement of mutual diffusion coefficients of gases by the Taylor method: Measurements on H2,Air,H2,N2, and H2,O2 systemsHEAT TRANSFER - ASIAN RESEARCH (FORMERLY HEAT TRANSFER-JAPANESE RESEARCH), Issue 3 2002Naoki Matsunaga Abstract Mutual diffusion coefficients of hydrogen gas (H2) into air and its component gases (N2 and O2) have been measured in the temperature range of 30 to 180°C and at atmospheric pressure via the Taylor dispersion method. For a H2,N2 system, the composition dependence of the mutual diffusion coefficient has been studied with both H2 and N2 as the carrier gas. The mutual diffusion coefficients for the H2,air and H2,N2 systems are almost the same and smaller than that for the H2,O2 system by about 5%. The present data for the H2,N2 system, corrected to an equimolar composition, agree well with the accurate data reported by the groups of P. J. Dunlop and of R. J. J. Van Heijningen. © 2002 Wiley Periodicals, Inc. Heat Trans Asian Res, 31(3): 182,193, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.10025 [source] Formation of Highly Crystallized ,-PbO Thin Films by Cathodic Electrodeposition of Pb and Its Rapid Oxidation in Air,ADVANCED FUNCTIONAL MATERIALS, Issue 2 2005S. Sawatani Abstract The process of electrodeposition of ,-PbO thin films from aqueous solutions of PbII salts has been studied in detail. Contrary to the mechanism assumed in previous studies, thin films of crystalline ,-PbO are obtained after cathodic electrolysis in aqueous solutions of various soluble salts of PbII (Pb(NO3)2, Pb(ClO4)2, and Pb(CH3COO)2), and in both the presence and the absence of O2, thus indicating no contribution of OH, generation by electroreduction of NO3, and/or O2 to the formation of ,-PbO. A gradual color change is noted: a freshly electrodeposited gray film turns yellow as it dries in air. Drying of the films under controlled atmosphere (Ar or O2), combined with scanning electron microscopy (SEM) observation and X-ray diffraction (XRD) measurement, has revealed that freshly deposited films are of metallic Pb, which are oxidized and converted into ,-PbO. Such a reaction is operative only when a freshly electrodeposited activated wet Pb film is in contact with gaseous O2. Despite the rapid conversion of a solid material, the resultant ,-PbO thin films are highly crystallized and possess highly ordered internal nanostructure. Elongated nanoparticles (30,nm,×,100,nm) are assembled in a regular alignment to compose a large platelet (greater than 10,,m in size) with single-crystalline character, as revealed by transmission electron microscopy (TEM) observation and selected-area electron diffraction (SAED) measurement. [source] Guest editorial: CFD In Indoor AirINDOOR AIR, Issue 1 2003Dan Nørtoft Sørensen No abstract is available for this article. [source] The Right to Healthy Indoor AirINDOOR AIR, Issue 4 2000LARS MØLHAVE [source] Characterization and Variability of Endotoxin and 3-Hydroxy Fatty Acids in an Office Building During a Particle Intervention StudyINDOOR AIR, Issue 1 2000Cynthia J. Hines Abstract Air and dust samples were collected on two floors of an office building during a double-blind particle intervention study to examine spatial and temporal variability of airborne endotoxin over a period of weeks, and to characterize endotoxin activity and lipopolysaccharide (LPS) content in carpet and chair dust. Air samples were collected on multiple days within and across weeks. Dust samples were collected from carpets and chairs one day per week for three weeks. Endotoxin was measured using a Limulus assay. Dust samples were analyzed for LPS by determination of 3-hydroxy fatty acids (3-OHFAs) using gas chromatography-mass spectrometry. The geometric mean (geometric standard deviation) for 96 indoor air samples was 0.24 (1.6) EU/m3. Significant within-floor spatial variation of airborne endotoxin was found (P<0.0001, n=80). Temporal variability of airborne endotoxin was not significant across weeks. Mean (±SD) endotoxin levels in carpet dust (59±9.3 EU/mg dust, n=12) and in chair dust (38±7.7 EU/mg dust, n=10) were significantly different (P<0.001). Carbon chain length-dependent differences in 3-OHFA levels by dust source and floor were found. Enhanced air filtration did not significantly affect airborne endotoxin (P=0.62); however, total dust mass and total endotoxin in carpet dust samples increased significantly after enhanced surface cleaning (P<0.01). These findings suggest that spatial variability, dust source, and surface cleaning may influence building occupant exposures to endotoxin., [source] Highly Conductive Sheets from Millimeter-Long Single-Walled Carbon Nanotubes and Ionic Liquids: Application to Fast-Moving, Low-Voltage Electromechanical Actuators Operable in AirADVANCED MATERIALS, Issue 16 2009Ken Mukai Ionic liquids allow millimeter-long single-walled carbon nanotubes to associate tightly, forming a free-standing sheet with superb mechanical and electrical properties. An actuator strip, fabricated by sandwiching an ionic-liquid-gel electrolyte layer with the nanotubes sheets obtained exhibits a large deformation in quick response (4,mm per 0.05 s) to low applied voltages, and a high durability upon 10 000 times continuous operations. [source] Control of Domain Orientation in Block Copolymer Electrolyte Membranes at the Interface with Humid AirADVANCED MATERIALS, Issue 2 2009Moon Jeong Park Domain orientation in polymer electrolyte membranes is tuned by controlling its sulfonation level and the moisture content of the air. At low sulfonation levels, highly ordered hydrophobic cylinders oriented perpendicular to the film surface are obtained, when the film is in humid air. Increasing the sulfonation level results in a transition from perpendicular to parallel orientation. [source] Seasonal variability in the response of the airflow characteristics to the changes in the macro-scale westerly flow intensity over Europe, 1971,2000INTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 4 2009Michal Marosz Abstract The aim of the research was to identify the seasonal variability of correlation between the air motion characteristics and common zonal circulation index (Rossby's Index). Air flow characteristics comprised divergence and vorticity. The spatial coverage of the research was the so called Euro-Atlantic Region covering parts of North Atlantic and Europe (40W,40E, 35N,75N). Temporal extent was 1971,2000 thus matching the latest WMO normal period. The data used was the components of the wind vector (u,zonal component, v,meridional component) and geopotential heights (hgt) from NCEP/NCAR Reanalysis. The response of the vorticity field is apparent and the greatest variability is noted at 1000 hPa. The mid and upper levels in the troposphere reveal quite homogenous response of vorticity to the macro-scale forcing. The response of the divergence field is also apparent though more complex in the vertical profile of the troposphere. The analysis of correlation was followed by the description of annual as well as seasonal shape of vorticity and divergence fields in the extremes of Rossby Index. Copyright © 2008 Royal Meteorological Society [source] The role of the oceans in climateINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 10 2003G. R. Bigg Abstract The ocean is increasingly seen as a vital component of the climate system. It exchanges with the atmosphere large quantities of heat, water, gases, particles and momentum. It is an important part of the global redistribution of heat from tropics to polar regions keeping our planet habitable, particularly equatorward of about 30°. In this article we review recent work examining the role of the oceans in climate, focusing on research in the Third Assessment Report of the IPCC and later. We discuss the general nature of oceanic climate variability and the large role played by stochastic variability in the interaction of the atmosphere and ocean. We consider the growing evidence for biogeochemical interaction of climatic significance between ocean and atmosphere. Air,sea exchange of several radiatively important gases, in particular CO2, is a major mechanism for altering their atmospheric concentrations. Some more reactive gases, such as dimethyl sulphide, can alter cloud formation and hence albedo. Particulates containing iron and originating over land can alter ocean primary productivity and hence feedbacks to other biogeochemical exchanges. We show that not only the tropical Pacific Ocean basin can exhibit coupled ocean,atmosphere interaction, but also the tropical Atlantic and Indian Oceans. Longer lived interactions in the North Pacific and Southern Ocean (the circumpolar wave) are also reviewed. The role of the thermohaline circulation in long-term and abrupt climatic change is examined, with the freshwater budget of the ocean being a key factor for the degree, and longevity, of change. The potential for the Mediterranean outflow to contribute to abrupt change is raised. We end by examining the probability of thermohaline changes in a future of global warming. Copyright © 2003 Royal Meteorological Society [source] Anatase and Rutile TiO2 Macrocellular Foams: Air,Liquid Foaming Sol,Gel Process Towards Controlling Cell Sizes, Morphologies, and Topologies,ADVANCED MATERIALS, Issue 1 2005F. Carn Titania foams (see Figure) can be produced using a non-static air,liquid foaming sol,gel process where nitrogen is bubbled through a mixture of a surfactant and a sol,gel precursor. Either anatase or rutile phase mesoporous titania foams are produced upon thermal treatment. Macroscopic cell morphologies can be tuned by changing the air-to-liquid-foam ratios and the size of the nitrogen bubbles, while wall topologies can be varied by changing surfactant. [source] Iodine-Catalyzed Suzuki,Miyaura Coupling Performed in AirADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 4 2009Jincheng Mao Abstract Suzuki-type coupling reactions can be performed directly in air using a catalytic system composed of iodine, potassium carbonate, and polyethylene glycol 400 (I2/K2CO3/PEG-400). Iodine was found to be an effective additive for accelerating these couplings. The methodology is also suitable for the coupling of (E)- , -bromostyene with phenylboronic acid, with retention of the double bond geometry. [source] | ||||||||||||||||||||||||||||||||||||||||||||||||||||