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Green
Kinds of Green Terms modified by Green Selected AbstractsCompensation for light loss due to filtering by macular pigment: relation to hue cancellationOPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 3 2007James M. Stringham Abstract Background:, A long-standing question in colour vision research is how the visual system is able to correct for the significant absorbance of short wave light by the crystalline lens and macular pigment (MP). Such compensation must be required in order to maintain colour constancy across the retina where MP levels are changing quickly and dramatically. Objective:, We studied this compensation mechanism by measuring MP spatial density profiles and hue cancellation functions across the central retina in a sample of six young healthy subjects. Method:, Yellow (Y, 575 nm)/blue (B, 440 nm) and red (R, 600 nm)/green (G, 501 nm) cancellation functions were obtained at 0, 1, 1.75, 3 and 7° eccentricity. The MP optical density at 460 nm was measured at these same eccentricities using heterochromatic flicker photometry. One subject was assessed repeatedly over a 4-month period during daily supplementation with 30 mg of lutein (L). Results:, Hue cancellation values for the Y/B system did not change across the retina (r = 0.09). In contrast, R/G sensitivity changed as a direct function of MP absorbance (r = 0.99). The Y/B values did not change in the one subject supplemented with 30 mg L daily, despite increases in MP of about 50% over 4 months. Conclusions:, Despite large variations in MP across the retina, hue cancellation values for the Y-B system across the central retina were constant. For example, one subject's MP density declined from a central peak of 0.99 to near zero at 7° (near 90% transmission difference) yet thresholds for the Y/B system were unaffected. In contrast, the G lobe of the R/G system was directly correlated with MP density. Taken together, these results confirm that the Y/B system compensates for MP density, but the R/G system does not. [source] BUYING LOCAL IS NOT NECESSARILY GREENECONOMIC AFFAIRS, Issue 2 2008Andrew Lilico Environmentalists are urging consumers to stop buying imports that needed to be transported long distances. However, the domestic production of the same goods would typically involve a much greater use of resources and therefore be counter-productive. [source] TAXONOMIC STUDY OF TWO NEW GENERA OF FUSIFORM GREEN FLAGELLATES, TABRIS GEN.JOURNAL OF PHYCOLOGY, Issue 2 2009On the basis of LM, we isolated strains of two species of fusiform green flagellates that could be assigned to former Chlorogonium (Cg.) Ehrenb. One species, "Cg."heimii Bourr., lacked a pyrenoid in its vegetative cells and required organic compounds for growth. The other was similar to Cg. elongatum (P. A. Dang.) Francé and "Cg."acus Nayal, but with slightly smaller vegetative cells. Their molecular phylogeny was also studied based on combined 18S rRNA, RUBISCO LSU (rbcL), and P700 chl a -apoprotein A2 (psaB) gene sequences. Both species were separated from Chlorogonium emend., Gungnir Nakada and Rusalka Nakada, which were formerly assigned to Chlorogonium. They were accordingly assigned to new genera, Tabris Nakada gen. nov. and Hamakko (Hk.) Nakada gen. nov. as T. heimii (Bourr.) Nakada comb. nov. and Hk. caudatus Nakada sp. nov., respectively. Tabris is differentiated from other genera of fusiform green flagellates by its vegetative cells, which only have two apical contractile vacuoles and lack a pyrenoid in the chloroplast. Hamakko, on the other hand, is distinguishable by the fact that its pyrenoids in vegetative cells are penetrated by flattened thylakoid lamellae. [source] COMMON EVOLUTIONARY ORIGIN OF STARCH BIOSYNTHETIC ENZYMES IN GREEN AND RED ALGAE,JOURNAL OF PHYCOLOGY, Issue 6 2005Nicola J. Patron Plastidic starch synthesis in green algae and plants occurs via ADP-glucose in likeness to prokaryotes from which plastids have evolved. In contrast, floridean starch synthesis in red algae proceeds via uridine diphosphate-glucose in semblance to eukaryotic glycogen synthesis and occurs in the cytosol rather than the plastid. Given the monophyletic origin of all plastids, we investigated the origin of the enzymes of the plastid and cytosolic starch synthetic pathways to determine whether their location reflects their origin,either from the cyanobacterial endosymbiont or from the eukaryotic host. We report that, despite the compartmentalization of starch synthesis differing in green and red lineages, all but one of the enzymes of the synthetic pathways shares a common origin. Overall, the pathway of starch synthesis in both lineages represents a chimera of the host and endosymbiont glycogen synthesis pathways. Moreover, host-derived proteins function in the plastid in green algae, whereas endosymbiont-derived proteins function in the cytosol in red algae. This complexity demonstrates the impacts of integrating pathways of host with those of both primary and secondary endosymbionts during plastid evolution. [source] LEAN, GREEN, AND THE QUEST FOR SUPERIOR ENVIRONMENTAL PERFORMANCEPRODUCTION AND OPERATIONS MANAGEMENT, Issue 3 2001SANDRA ROTHENBERG We examine the relationship between lean manufacturing practices and environmental performance as measured in terms of air emissions and resource use. We draw on two unique surveys of 31 automobile assembly plants in North America and Japan, which contain information on manufacturing practice and environmental performance, as well as in-depth interviews with 156 plant level employees at 17 assembly plants. Our survey results and interviews suggest that lean management and reduction of air emissions of volatile organic compounds (vocs) are associated negatively. Lean manufacturing practices contribute to more efficient use of paints and cleaning solvents, but these in-process changes are not sufficient to meet the most stringent air regulations. We found some evidence to support the link between lean practices and resource efficiency. While our survey results were in hypothesized direction, they were not statistically significant. In-depth semi-structured interviews, however, suggest a more robust relationship, and we use them to describe some mechanisms by which all three aspects of lean management (buffer minimization, work systems, and human resource management) may be related to environmental management practices and performance. [source] THE SECTILIA PANELS OF FARAGOLA (ASCOLI SATRIANO, SOUTHERN ITALY): A MULTI-ANALYTICAL STUDY OF THE GREEN, MARBLED (GREEN AND YELLOW), BLUE AND BLACKISH GLASS SLABSARCHAEOMETRY, Issue 3 2010E. GLIOZZO Analyses at the Cu,K, Fe,K and Mn,K edge were performed to study the green, marbled (green and yellow), blue and blackish (deep greyish olive green) glass slabs decorating three sectilia panels from the archaeological site of Faragola. Results indicate that all slabs were made by mixing siliceous sand with natron, sometimes probably mixed with small percentages of plant ash. Cu2+ and Pb antimonates should be responsible for the opaque green colours. The dark green and yellow portions of the marbled slabs are respectively comparable to the slabs comprising only one of these colours. Cu2+ together with Ca antimonates probably produced light blue slabs, whereas cobalt was used to produce dark blue slabs. We consider it possible that the abundance ratio of Fe2+/Fe3+ and the complex Fe3+S2, would have an effect on the blackish slabs. The contribution of Mn cannot be ascertained even if it could have played a role in darkening glass colour. The comparison between the chemical composition of Faragola samples and several glass reference groups provided no conclusive evidence of provenance; whereas, the presence of a secondary local workshop can be hypothesized. [source] Severing of F-actin by yeast cofilin is pH-independentCYTOSKELETON, Issue 9 2006Dmitry Pavlov Abstract Cofilin plays an important role in actin turnover in cells by severing actin filaments and accelerating their depolymerization. The role of pH in the severing by cofilin was examined using fluorescence microscopy. To facilitate the imaging of actin filaments and to avoid the use of rhodamine phalloidin, which competes with cofilin, ,-actin was labeled with tetramethylrhodamine cadaverine (TRC) at Gln41. The TRC-labeling inhibited actin treadmilling strongly, as measured by ,ATP release. Cofilin binding, detected via an increase in light scattering, and the subsequent conformational change in filament structure, as detected by TRC fluorescence decay, occurred 2,3 times faster at pH 6.8 than at pH 8.0. In contrast, actin filaments severing by cofilin was pH-independent. The pH-independent severing by cofilin was confirmed using actin labeled at Cys374 with Oregon Green® 488 maleimide. The depolymerization of actin by cofilin was faster at high pH. Cell Motil. Cytoskeleton 2006. © 2006 Wiley-Liss, Inc. [source] From Poverty to Power: How Active Citizens and Effective States can Change the World,by Duncan GreenDEVELOPMENT AND CHANGE, Issue 4 2009Sylvia I. Bergh No abstract is available for this article. [source] Electrochemical Preparation of Poly(Malachite Green) Film Modified Nafion-Coated Glassy Carbon Electrode and Its Electrocatalytic Behavior Towards NADH, Dopamine and Ascorbic AcidELECTROANALYSIS, Issue 14 2007Shen-Ming Chen Abstract Poly(malachite green) film modified Nafion-coated glassy carbon electrodes have been prepared by potentiodynamic cycling in malachite green solution. The pH of polymerisation solution has only minor effect on film formation. Electrochemical quartz crystal microbalance (EQCM) was used to monitor the growth of the poly(malachite green) film. Cyclic voltammogram of the poly(malachite green) film shows a redox couple with well-defined peaks. The redox response of the modified electrode was found to be depending on the pH of the contacting solution. The peak potentials were shifted to a less positive region with increasing pH and the dependence of the peak potential was found to be 56,mV per pH unit. The electrocatalytic behavior of poly(malachite green) film modified Nafion-coated glassy carbon electrodes was tested towards oxidation of NADH, dopamine, and ascorbic acid. The oxidation of dopamine and ascorbic acid occurred at less positive potential on poly(malachite green) film compared to bare glassy carbon electrode. In the case of NADH, the overpotential was reduced substantially on modified electrode. Finally, the feasibility of utilizing poly(malachite green) film electrode in analytical estimation of ascorbic acid was demonstrated in flow injection analysis. [source] Determination of DNA methylation by COBRA: A comparative study of CGE with LIF detection and conventional gel electrophoresisELECTROPHORESIS, Issue 17 2009Simon Goedecke Abstract DNA methylation as an epigenetic modification of the human genome is under emphatic investigation. Several studies have demonstrated a role of DNA methylation in oncogenesis. In conjunction with histone modifications, DNA methylation may cause the formation of heterochromatin and thus mediate the inactivation of gene transcription. It is important to develop methods that allow for an accurate quantification of the amount of DNA methylation in particular DNA regions, to gain information concerning the threshold of methylation levels necessary for gene inactivation. In this article, a CGE method with on-column LIF detection using SYBR Green is compared with a conventional slab-gel electrophoresis. We thus investigate the validity to analyze DNA methylation in the samples of a combined bisulfite restriction analysis. It is demonstrated that CGE is superior to gel electrophoresis in means of linearity, precision, accuracy, automatization (high throughput), and sample consumption. However, gel electrophoresis is easier to perform (simple devices, no PC usage), and the running costs are comparatively low. A further advantage of CGE is the sparse use of toxic compounds (MeOH and SYBR Green), whereas gel electrophoresis is performed in polyacrylamide gels with ethidium bromide staining. [source] Temperature gradient focusing in a PDMS/glass hybrid microfluidic chipELECTROPHORESIS, Issue 24 2007Takuya Matsui Abstract This paper reports the application of temperature gradient focusing (TGF) in a PDMS/glass hybrid microfluidic chip. With TGF, by the combination of a temperature gradient along a microchannel, an applied electric field, and a buffer with a temperature-dependent ionic strength, analytes are focused by balancing their electrophoretic velocities against the bulk velocity of the buffer containing the analytes. In this work, Oregon Green 488 carboxylic acid was concentrated approximately 30 times as high as the initial concentration in 45,s at moderate electric strength of 70,V/cm and a temperature gradient of 55°C across the PDMS/glass hybrid microfluidic chip with a 1,cm long capillary. [source] Potential Applications of Oxidoreductases for the Re-oxidation of Leuco Vat or Sulfur Dyes in Textile DyeingENGINEERING IN LIFE SCIENCES (ELECTRONIC), Issue 3 2008F. Xu Abstract Conventional textile dyeing by vat and sulfur dyes includes reduction and re-oxidation steps (with chemical reductants and oxidants), so that the insoluble dyes can be solubilized in the dyeing solution, adsorbed by the fabric, and fixed onto the dyed fabric. The treatments often involve hazardous chemicals, expensive catalysts, or conditions that are suboptimally effective, energy-intensive, caustic, or polluting. Improving these steps with enzyme technology could be of significant interest in terms of better dyeing, handling of hazardous chemicals, disposal of waste, or production economy. The idea of an enzymatic re-oxidation step for vat and sulfur dyeings was tested under simplified laboratory conditions. Selected vat and sulfur dyes, including Vat Blue,43, Vat Orange,7, Vat Green,3, Vat Orange,2, Vat Red,13, Vat Yellow,2, and Sulfur Black,1, were first chemically reduced. The reduced (leuco) dyes were then re-oxidized by aerated buffer solutions or H2O2, in the presence or absence of an oxidoreductase, selected from seven laccases from Myceliophthora thermophila, Scytalidium thermophilum, Coprinus cinereus, Trametes villosa, Rhizoctonia solani, Pycnoporus cinnabarinus, Botrytis cinerea, a bilirubin oxidase from Myrothecium verrucaria, and a heme peroxidase from Coprinus cineresu. It was shown that the enzymes were able to catalyze and accelerate the re-oxidation of the reduced dyes, even when they were adsorbed on cotton fabric, by dissolved air (O2) or H2O2. Small redox-active mediators could facilitate the enzymatic re-oxidation. For Sulfur Black,1, a higher conversion of the leuco dye was achieved with laccase-catalyzed re-oxidation. The further development of this potential enzyme application is discussed. [source] Community heterogeneity and single-cell digestive activity of estuarine heterotrophic nanoflagellates assessed using lysotracker and flow cytometryENVIRONMENTAL MICROBIOLOGY, Issue 7 2010Eva Sintes Summary Heterotrophic nanoflagellates (HNFs) are an essential component of all aquatic microbial food webs, and yet the exploration of the numerical and single-cell responses of these organisms in mixed assemblages still represents a major technical challenge. LysoTracker Green staining combined with flow cytometry was recently proposed for the enumeration of aquatic HNFs. Here we show that LysoTracker Green not only allows the enumeration of HNFs in estuarine samples with a wide range of HNF abundances, but also allows the discrimination of distinct HNF populations in mixed assemblages. In addition, the resulting cytometric parameters can be used to characterize cell size and the level of activity of the cells in the different populations that are detected. LysoTracker Green accumulates preferentially in lysosomes, and we demonstrate that the green fluorescence emission from HNF cells stained with LysoTracker strongly correlates with cell-specific ,-glucosaminidase (,-Gam) activity, a key digestive enzyme of lysosomal origin in eukaryotic cells. Our results further show that different populations that develop in estuarine regrowth cultures are characterized by different intrinsic ranges of size and of feeding activity, and that there is a wide range of single-cell responses within these HNF populations. We found a large degree of uncoupling between cell size and feeding activity, both between and within HNF populations, and there appears to be no clear allometric scaling of feeding activity. We were able to reconstruct the succession of distinct HNF populations that developed during the regrowth experiments, and explore the complex interactions that occurred between numerical (change in abundance of the cytometric populations) and single-cell HNF responses. [source] Adaptation to climate change in the European union: efficiency versus equity considerationsENVIRONMENTAL POLICY AND GOVERNANCE, Issue 3 2010Stine Aakre Abstract EU climate policy based on reduction (mitigation) of greenhouse gas emissions is coupled with measures aimed at responding efficiently to the unavoidable consequences of climate change (adaptation). However, as the European Commission stated recently in its Green and White Papers on adaptation in Europe, there is still need to develop an overall EU adaptation strategy. Moreover, such a strategy should take into consideration both efficiency and equity concerns. In this article we propose a framework for EU adaptation policy that addresses the two concerns and which enables a transparent decision-making process. In the proposed scheme universal weightings of the individual policy objectives have to be agreed upon prior to actual decision-making. Copyright © 2010 John Wiley & Sons, Ltd and ERP Environment. [source] The Reductive Elimination of Methane from ansa -Hydrido(methyl)metallocenes of Molybdenum and Tungsten: Application of Hammond's Postulate to Two-State ReactionsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 15 2005José-Luis Carreón-Macedo Abstract The energetic profile of the methane reductive elimination from a selected number of hydrido(methyl)molybdenocene and -tungstenocene derivatives has been calculated by DFT methods. The calculations were carried out for the CH2(C5H4)2M (a -M), SiH2(C5H4)2M (a -H2Si,M), and SiMe2(C5Me4)2M (a -Me2Si,M*) ansa -metallocene systems for M = Mo, W. They include the full optimization of minima [the hydrido(methyl) starting complexes, M(H)(CH3), the intermediate methane complexes, M(CH4), and the metallocene products in the singlet and triplet configurations, (3M and 1M)], transition states (for the methyl hydride reductive elimination, M,TSins, and for the hydrogen exchange, M,TSexch), and the minimum energy crossing point (M,MECP) leading from the singlet methane complexes to the corresponding triplet metallocenes. The results are compared with those previously obtained for the simpler (C5H5)2M (Cp2M) systems (J. C. Green, J. N. Harvey, and R. Poli, J. Chem. Soc., Dalton Trans.2002, 1861). The calculated energy profiles, notably the relative energies of M,TSins and M,MECP, are in agreement with available experimental observations for the a -Me2Si,M* systems. The comparison of the energies and geometries of the rate-determining M,TSins and M,MECP structures with those of the thermodynamically relevant minima for the various systems show the applicability of Hammond's postulate to two-state reactions. However, one notable exception serves to show that the principle is only quantitatively reliable when all the potential energy surfaces for the set of analogous reactions have similar shapes. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] No evidence for calcium electrogenic exchanger in frog semicircular canal hair cellsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 9 2002M. Martini Abstract We investigated the possibility that, in hair cells mechanically isolated from frog semicircular canals, Ca2+ extrusion occurs via a Na+ : Ca2+ (cardiac type) or a Na+ : Ca2+,K+ (retinal type) exchanger. Cells concurrently imaged during whole-cell patch-clamp recordings using the Ca2+ sensitive fluorescent dye Oregon Green 488 BAPTA-1 (100 µm) showed no voltage dependence of Ca2+ clearance dynamics following a Ca2+ load through voltage-gated Ca2+ channels. Reverse exchange was probed in hair cells dialyzed with a Ca2+ - and K+ -free solution, containing a Na+ concentration that saturates the exchanger, after zeroing the contribution to the whole-cell current from Ca2+ and K+ conductances. In these conditions, no reverse exchange current was detected upon switching from a Ca2+ -free external solution to a solution containing concentrations of Ca2+ alone, or Ca2+ + K+ that saturated the exchanger. By contrast, the same experimental protocol elicited peak exchange currents exceeding 100 pA in gecko rod photoreceptors, used as positive controls. In both cell types, we also probed the forward mode of the exchanger by rapidly increasing the intracellular Ca2+ concentration using flash photolysis of two novel caged Ca2+ complexes, calcium 2,2,-{[1-(2-nitrophenyl)ethane-1,2-diyl]bis(oxy)}bis(acetate) and calcium 2,2,-{[1-(4,5-dimethoxy-2-nitrophenyl)ethane-1,2-diyl]bis(oxy)} bis(acetate), in the presence of internal K+ and external Na+. No currents were evoked by UV-triggered Ca2+ jumps in hair cells, whereas exchanger conformational currents up to 400 pA, followed by saturating forward exchange currents up to 40 pA, were recorded in rod photoreceptors subjected to the same experimental conditions. We conclude that no functional electrogenic exchanger is present in this hair cell population, which leaves the abundant plasma membrane Ca2+ -ATPases as the primary contributors to Ca2+ extrusion. [source] Green, Palladium-Catalyzed Synthesis of Benzylic H -Phosphinates from Hypophosphorous Acid and Benzylic AlcoholsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 24 2008Laëtitia Coudray Abstract Benzylic alcohols cross-couple directly with concentrated H3PO2 by using Pd/xantphos (1 or 2 mol-%). Depending on the substrate, DMF at 110 °C or t -AmOH at reflux with a Dean,Stark trap can be used. A broad range of benzylic alcohols react successfully to give moderate to good yields of the products. The preparation of other organophosphorus compounds (phosphinic and phosphonic acids) is also demonstrated. Asymmetric reaction with (R)-1-(2-naphthyl)ethanol provids the corresponding H -phosphinic acid in 77,% ee. The methodology provides a green, PCl3 -free route to benzylic- H -phosphinic acids.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] An Island of Green in the Sunburnt Country: The Rainforest of the Humid Tropics of Northeastern Australia and Their Response to Quaternary Environmental ChangeGEOGRAPHY COMPASS (ELECTRONIC), Issue 6 2008Patrick T. Moss The Humid Tropics of northeastern Australia is a region of exceptional diversity and productivity that reflects many of the characteristics of similar tropical biomes. In the Australian context, it is a unique environment being a virtual ,island of green' surrounded by the more typical sclerophyll (i.e. dry and fire prone) landscapes of Australia. This article will examine the modern ecological characteristics of the region, as well as providing historical context by discussing the response of the humid tropics communities to Quaternary environmental upheavals and the possible implications that these alterations have for understanding ecosystem response to future environmental change. [source] The Lisse Effect RevisitedGROUND WATER, Issue 6 2002Edwin P. Weeks The Lisse effect is a rarely noted phenomenon occurring when infiltration caused by intense rain seals the surface soil layer to airflow, trapping air in the unsaturated zone. Compression of air by the advancing front results in a pressure increase that produces a water-level rise in an observation well screened below the water table that is several times as large as the distance penetrated by the wetting front. The effect is triggered by intense rains and results in a very rapid water-level rise, followed by a recession lasting a few days. The Lisse effect was first noted and explained by Thal Larsen in 1932 from water-level observations obtained in a shallow well in the village of Lisse, Holland. The original explanation does not account for the increased air pressure pushing up on the bottom of the wetting front. Analysis of the effect of this upward pressure indicates that a negative pressure head at the base of the wetting front, ,f, analogous to that postulated by Green and Ampt (1911) to explain initially rapid infiltration rates into unsaturated soils, is involved in producing the Lisse effect. Analysis of recorded observations of the Lisse effect by Larsen and others indicates that the water-level rise, which typically ranges from 0.10 to 0.55 m, should be only slightly larger than |,f| and that the depth of penetration of the wetting front is no more than several millimeters. [source] Workforce Development Networks in Rural Areas: Building the High Road , By Gary Paul GreenGROWTH AND CHANGE, Issue 1 2009Chris Benner First page of article [source] Molecular dynamics simulation of self-diffusion coefficient and its relation with temperature using simple Lennard-Jones potentialHEAT TRANSFER - ASIAN RESEARCH (FORMERLY HEAT TRANSFER-JAPANESE RESEARCH), Issue 2 2008Li Wei-Zhong Abstract The diffusion coefficient is indispensable to chemical engineering design and research. In practical engineering and research, there is still a great lack of available data. Therefore, methods need to be developed to solve this problem. In this paper, a molecular dynamics simulation method is used to predict the self-diffusion coefficient for a simple fluid by using the Green, Kubo relation (VACF) and the Einstein relation (MSD). The simulation results are in good agreement with experimental findings except for an error of about 10%. The algorithm average of the two methods (AV) reduces the error to 7%. The relationship of the diffusion coefficient with temperature has also been simulated. According to the simulation data, whose correlation is all above 0.99, the diffusion coefficient agrees well with temperature following the Arrenhius relationship. Activation energy for self-diffusion has been calculated and the result were 1258(VACF), 1272(MSD), and 1265(AV) J/mol separately. © 2008 Wiley Periodicals, Inc. Heat Trans Asian Res, 37(2): 86,93, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20191 [source] A study on thermal conductivity of a quasi-ordered liquid layer on a solid substrateHEAT TRANSFER - ASIAN RESEARCH (FORMERLY HEAT TRANSFER-JAPANESE RESEARCH), Issue 7 2007Xiao-Yan Shi Abstract In the present paper, a study on thermal conductivity of a quasi-ordered liquid layer on a solid surface was performed by molecular dynamic simulation. Results showed that the motion of the molecules and their radial distribution function in the quasi-ordered liquid layer were similar to those of solid molecules. By using the Green,Kubo formula, the thermal conductivity of the layer was calculated. It was found that it increased with the increase of the parameters of ordering. The size effect and the influence of the boundary condition were also discussed. © 2007 Wiley Periodicals, Inc. Heat Trans Asian Res, 36(7): 429,434, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20171 [source] A Highly Efficient Universal Bipolar Host for Blue, Green, and Red Phosphorescent OLEDsADVANCED MATERIALS, Issue 22 2010Ho-Hsiu Chou The bipolar host material BCPO (bis-4- (N-carbazolyl)phenylphosphine oxide) containing a phosphine oxide and two carbazole groups, synthesized in three steps, shows a high triplet energy gap of 3.01,eV. The material can be used as a universal host for blue, green, and red phosphorescent devices, all giving extremely high efficiencies with turn-on voltages within 3 V. [source] The effect of soil type, meteorological forcing and slope gradient on the simulation of internal erosion processes at the local scaleHYDROLOGICAL PROCESSES, Issue 13 2010Guillaume Nord Abstract Numerical simulation experiments of water erosion at the local scale (20 × 5 m) using a process-based model [Plot Soil Erosion Model_2D (PSEM_2D)] were carried out to test the effects of various environmental factors (soil type, meteorological forcing and slope gradient) on the runoff and erosion response and to determine the dominant processes that control the sediment yield at various slope lengths. The selected environmental factors corresponded to conditions for which the model had been fully tested beforehand. The use of a Green and Ampt model for infiltration explained the dominant role played by rainfall intensity in the runoff response. Sediment yield at the outlet of the simulated area was correlated positively with rainfall intensity and slope gradient, but was less sensitive to soil type. The relationship between sediment yield (soil loss per unit area) and slope length was greatly influenced by all environmental factors, but there was a general tendency towards higher sediment yield when the slope was longer. Contribution of rainfall erosion to gross erosion was dominant for all surfaces with slope lengths ranging from 4 to 20 m. The highest sediment yields corresponded to cases where flow erosion was activated. An increase in slope gradient resulted in flow detachment starting upstream. Sediment exported at the outlet of the simulated area came predominantly from the zone located near the outlet. The microrelief helped in the development of a rill network that controlled both the ratio between rainfall and flow erosion and the relationship between sediment yield and slope length. Copyright © 2010 John Wiley & Sons, Ltd. [source] Runoff and suspended sediment yields from an unpaved road segment, St John, US Virgin IslandsHYDROLOGICAL PROCESSES, Issue 1 2007Carlos E. Ramos-Scharrón Abstract Unpaved roads are believed to be the primary source of terrigenous sediments being delivered to marine ecosystems around the island of St John in the eastern Caribbean. The objectives of this study were to: (1) measure runoff and suspended sediment yields from a road segment; (2) develop and test two event-based runoff and sediment prediction models; and (3) compare the predicted sediment yields against measured values from an empirical road erosion model and from a sediment trap. The runoff models use the Green,Ampt infiltration equation to predict excess precipitation and then use either an empirically derived unit hydrograph or a kinematic wave to generate runoff hydrographs. Precipitation, runoff, and suspended sediment data were collected from a 230 m long, mostly unpaved road segment over an 8-month period. Only 3,5 mm of rainfall was sufficient to initiate runoff from the road surface. Both models simulated similar hydrographs. Model performance was poor for storms with less than 1 cm of rainfall, but improved for larger events. The largest source of error was the inability to predict initial infiltration rates. The two runoff models were coupled with empirical sediment rating curves, and the predicted sediment yields were approximately 0·11 kg per square meter of road surface per centimetre of precipitation. The sediment trap data indicated a road erosion rate of 0·27 kg m,2 cm,1. The difference in sediment production between these two methods can be attributed to the fact that the suspended sediment samples were predominantly sand and silt, whereas the sediment trap yielded mostly sand and gravel. The combination of these data sets yields a road surface erosion rate of 0·31 kg m,2 cm,1, or approximately 36 kg m,2 year,1. This is four orders of magnitude higher than the measured erosion rate from undisturbed hillslopes. The results confirm the importance of unpaved roads in altering runoff and erosion rates in a tropical setting, provide insights into the controlling processes, and provide guidance for predicting runoff and sediment yields at the road-segment scale. Copyright © 2006 John Wiley & Sons, Ltd. [source] Power function decay of hydraulic conductivity for a TOPMODEL-based infiltration routineHYDROLOGICAL PROCESSES, Issue 18 2006Jun Wang Abstract TOPMODEL rainfall-runoff hydrologic concepts are based on soil saturation processes, where soil controls on hydrograph recession have been represented by linear, exponential, and power function decay with soil depth. Although these decay formulations have been incorporated into baseflow decay and topographic index computations, only the linear and exponential forms have been incorporated into infiltration subroutines. This study develops a power function formulation of the Green and Ampt infiltration equation for the case where the power n = 1 and 2. This new function was created to represent field measurements in the New York City, USA, Ward Pound Ridge drinking water supply area, and provide support for similar sites reported by other researchers. Derivation of the power-function-based Green and Ampt model begins with the Green and Ampt formulation used by Beven in deriving an exponential decay model. Differences between the linear, exponential, and power function infiltration scenarios are sensitive to the relative difference between rainfall rates and hydraulic conductivity. Using a low-frequency 30 min design storm with 4·8 cm h,1 rain, the n = 2 power function formulation allows for a faster decay of infiltration and more rapid generation of runoff. Infiltration excess runoff is rare in most forested watersheds, and advantages of the power function infiltration routine may primarily include replication of field-observed processes in urbanized areas and numerical consistency with power function decay of baseflow and topographic index distributions. Equation development is presented within a TOPMODEL-based Ward Pound Ridge rainfall-runoff simulation. Copyright © 2006 John Wiley & Sons, Ltd. [source] SWAT2000: current capabilities and research opportunities in applied watershed modellingHYDROLOGICAL PROCESSES, Issue 3 2005J. G. Arnold Abstract SWAT (Soil and Water Assessment Tool) is a conceptual, continuous time model that was developed in the early 1990s to assist water resource managers in assessing the impact of management and climate on water supplies and non-point source pollution in watersheds and large river basins. SWAT is the continuation of over 30 years of model development within the US Department of Agriculture's Agricultural Research Service and was developed to ,scale up' past field-scale models to large river basins. Model components include weather, hydrology, erosion/sedimentation, plant growth, nutrients, pesticides, agricultural management, stream routing and pond/reservoir routing. The latest version, SWAT2000, has several significant enhancements that include: bacteria transport routines; urban routines; Green and Ampt infiltration equation; improved weather generator; ability to read in daily solar radiation, relative humidity, wind speed and potential ET; Muskingum channel routing; and modified dormancy calculations for tropical areas. A complete set of model documentation for equations and algorithms, a user manual describing model inputs and outputs, and an ArcView interface manual are now complete for SWAT2000. The model has been recoded into Fortran 90 with a complete data dictionary, dynamic allocation of arrays and modular subroutines. Current research is focusing on bacteria, riparian zones, pothole topography, forest growth, channel downcutting and widening, and input uncertainty analysis. The model SWAT is meanwhile used in many countries all over the world. Recent developments in European Environmental Policy, such as the adoption of the European Water Framework directive in December 2000, demand tools for integrative river basin management. The model SWAT is applicable for this purpose. It is a flexible model that can be used under a wide range of different environmental conditions, as this special issue will show. The papers compiled here are the result of the first International SWAT Conference held in August 2001 in Rauischholzhausen, Germany. More than 50 participants from 14 countries discussed their modelling experiences with the model development team from the USA. Nineteen selected papers with issues reaching from the newest developments, the evaluation of river basin management, interdisciplinary approaches for river basin management, the impact of land use change, methodical aspects and models derived from SWAT are published in this special issue. Copyright © 2005 John Wiley & Sons, Ltd. [source] Validation of a vegetated filter strip model (VFSMOD)HYDROLOGICAL PROCESSES, Issue 5 2001Dr Majed Abu-Zreig Abstract Vegetated filter strips (VFS) are designed to reduce sediment load and other pollutants into water bodies. However, adaptation of VFS in the field has been limited owing to lack of data about their efficiency and performance under natural field conditions. A number of models are available that simulate sediment transport and trapping in VFS, but there is a general lack of confidence in VFS models owing to limited validation studies and model limitations that prevent correct application of these models under field conditions. The objective of this study is to test and validate a process-based model (VFSMOD) that simulates sediment trapping in VFS. This model links three submodels: modified Green,Ampt's infiltration, Quadratic overland flow submodel based on kinematic wave approximation and University of Kentucky sediment filtration model. A total of 20 VFS, 2, 5, 10 and 15 m long and with various vegetation covers, were tested under simulated sediment and runoff conditions. The results of these field experiments were used to validate the VFS model. The model requires 25 input parameters distributed over five input files. All input parameters were either measured or calculated using experimental data. The observed sediment trapping efficiencies varied from 65% in the 2-m long VFS to 92% in the 10-m long filters. No increase in sediment removal efficiency was observed at higher VFS length. Application of the VFS model to experimental data was satisfactory under the condition that actual flow widths are used in the model instead of the total filter width. Predicted and observed sediment trapping efficiencies and infiltration volume fitted very well, with a coefficient of determination (R2) of 0·9 and 0·95, respectively. Regression analyses revealed that the slope and intercept of the regression lines between predicted versus observed infiltration volume and trapping efficiency were not significantly different than the line of perfect agreement with a slope of 1·0 and intercept of 0·0. Copyright © 2001 John Wiley & Sons, Ltd. [source] St. Thomas University: Which Balanced Scorecard to Use?,/ST.ACCOUNTING PERSPECTIVES, Issue 4 2007THOMAS UNIVERSITY: LE CHOIX D'UN TABLEAU DE BORD ABSTRACT This case provides background on a university that undertook a formal strategic-planning initiative. Mary White, Vice-President (Administration), was responsible for developing the performance evaluation framework. She established a special task force, which included Peter Crimson, Assistant Vice-President (Administration), Eva Black, Director of Financial Analysis, and Adam Green, Director of Planning and Analysis, to assist her in this endeavor. The special task force had an insightful discussion on the balanced scorecard during its first meeting. When the meeting concluded, Mary White asked Adam Green to conduct research on the different approaches to the balanced scorecard adopted in a number of universities. She expected Adam Green to provide an analysis of the different balanced scorecard approaches in universities, to make recommendations on the balanced scorecard approach that St. Thomas should adopt, and to develop a balanced scorecard for the university. An objective of the case is to provide students with an opportunity to evaluate the implementation of the balanced scorecard in universities, to recommend an approach for developing the performance evaluation framework, and to design a balanced scorecard for the university. RÉSUMÉ Le cas élaboré par l'auteure contient les données de base relatives au projet structuré de planification stratégique entrepris par une université. Mary White, vice-présidente à l'administration, assumait la responsabilité de l'élaboration du cadre d'évaluation de la performance. Elle a constitué un groupe de travail spécial, réunissant Peter Crimson, adjoint à la vice-présidente à l'administration, Eva Black, directrice de l'analyse financière, et Adam Green, directeur de la planification et de l'analyse, pour lui prêter main-forte dans cette entreprise. Lors de sa première réunion, le groupe de travail spécial a tenu une discussion instructive sur le tableau de bord. Au terme de cette réunion, Mary White a demandé à Adam Green de faire des recherches sur la façon dont différentes universités ont choisi de traiter le tableau de bord. Elle souhaitait obtenir une analyse des différentes méthodes utilisées dans les universités, des recommandations quant au choix de la méthode appropriée à St. Thomas et l'élaboration du tableau de bord de l'université. Ce cas a notamment pour objectif d'offrir aux étudiants l'occasion d'évaluer la mise en application du tableau de bord dans les universités, de recommander une méthode d'élaboration du cadre d'évaluation de la performance et de concevoir un tableau de bord pour l'université. [source] Some further properties of the superconvergent flux projectionINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 4 2002Graham F. Carey Abstract Some properties of the integral superconvergent flux (post-processing) projection formula are investigated: (1) A Green,Gauss formula together with the partition of unity property of the finite element basis imply global and local conservation properties and a local flux or stress recovery strategy; (2) The equivalence to a Lagrange multiplier mixed formulation is used to interpret the associated consistency requirement on the flux expansion via an inf,sup or LBB condition and (3) The resulting conditions on the flux basis are examined and the presence of oscillatory modes demonstrated. Copyright © 2002 John Wiley & Sons, Ltd. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||