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Efficient System (efficient + system)
Selected AbstractsChemInform Abstract: An Efficient System for the Pd-Catalyzed Cross-Coupling of Amides and Aryl Chlorides.CHEMINFORM, Issue 52 2009Brett P. Fors Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Molybdatophosphoric Acid/NaNO2/Wet SiO2 as an Efficient System for the Aromatization of 1,2-Dihydroquinolines under Mild and Heterogeneous Conditions.CHEMINFORM, Issue 41 2007Khodabakhsh Niknam Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Surfactant/I2/Water: An Efficient System for Deprotection of Oximes and Imines to Carbonyls under Neutral Conditions in Water.CHEMINFORM, Issue 31 2005Pranjal Gogoi Abstract For Abstract see ChemInform Abstract in Full Text. [source] Molybdatophosphoric Acid/NaNO2/Wet SiO2 as an Efficient System for Oxidation of 1,4-Dihydropyridines under Mild and Heterogeneous Conditions.CHEMINFORM, Issue 30 2005Khodabakhsh Niknam Abstract For Abstract see ChemInform Abstract in Full Text. [source] TiCl4, Dioxane , A Facile and Efficient System for De-O-Benzylation, De-O-Allylation, and De-O-Xylylation of Phenolic Ethers.CHEMINFORM, Issue 12 2004Perumal Rajakumar No abstract is available for this article. [source] Urea-Hydrogen Peroxide/Hexafluoro-2-propanol: An Efficient System for a Catalytic Epoxidation Reaction Without a Metal.CHEMINFORM, Issue 5 2003Julien Legros No abstract is available for this article. [source] A Novel and Efficient System of a Visible-Light-Responsive Organic Photoelectrocatalyst Working in a Water PhaseCHEMPHYSCHEM, Issue 5 2004Toshiyuki Abe Prof. The best of both worlds: An organic bilayer, composed of a perylene derivative (PV) and a phthalocyanine (H2Pc), was found to be a novel example of a photoanode involving a catalytic oxidation in water (see graphic). Based on the action spectrum for photocurrent, it is noted that the widespread visible light absorption (<750 nm) by only the PV can efficiently induce the photoanodic current generation at the interface of H2Pc/water coupled with the hole-conducting character of H2Pc. [source] Debris-covered Glaciers and Rock Glaciers in the Nanga Parbat Himalaya, PakistanGEOGRAFISKA ANNALER SERIES A: PHYSICAL GEOGRAPHY, Issue 1 2000John F. Shroder The origin and mobilization of the extensive debris cover associated with the glaciers of the Nanga Parbat Himalaya is complex. In this paper we propose a mechanism by which glaciers can form rock glaciers through inefficiency of sediment transfer from glacier ice to meltwater. Inefficient transfer is caused by various processes that promote plentiful sediment supply and decrease sediment transfer potential. Most debris-covered glaciers on Nanga Parbat with higher velocities of movement and/ or efficient debris transfer mechanisms do not form rock glaciers, perhaps because debris is mobilized quickly and removed from such glacier systems. Those whose ice movement activity is lower and those where inefficient sediment transfer mechanisms allow plentiful debris to accumulate, can form classic rock glaciers. We document here with maps, satellite images, and field observations the probable evolution of part of a slow and inefficient ice glacier into a rock glacier at the margins of Sachen Glacier in c. 50 years, as well as several other examples that formed in a longer period of time. Sachen Glacier receives all of its nourishment from ice and snow avalanches from surrounding areas of high relief, but has low ice velocities and no efficient system of debris removal. Consequently it has a pronounced digitate terminus with four lobes that have moved outward from the lateral moraines as rock glaciers with prounced transverse ridges and furrows and steep fronts at the angle of repose. Raikot Glacier has a velocity five times higher than Sachen Glacier and a thick cover of rock debris at its terminus that is efficienctly removed. During the advance stage of the glacier since 1994, ice cliffs were exposed at the terminus, and an outbreak flood swept away much debris from its margins and terminus. Like the Sachen Glacier that it resembles, Shaigiri Glacier receives all its nourishment from ice and snow avalanches and has an extensive debris cover with steep margins close to the angle of repose. It has a high velocity similar to Raikot Glacier and catastrophic breakout floods have removed debris from its terminus twice in the recent past. In addition, the Shaigiri terminus blocked the Rupal River during the Little Ice Age and is presently being undercut and steepened by the river. With higher velocities and more efficient sediment transfer systems, neither the Raikot nor the Shaigiri form classic rock-glacier morphologies. [source] SEQUENCE ANALYSIS AND TRANSCRIPTIONAL REGULATION OF IRON ACQUISITION GENES IN TWO MARINE DIATOMS,JOURNAL OF PHYCOLOGY, Issue 4 2007Adam B. Kustka The centric diatom Thalassiosira pseudonana Hasle et Heimdal and the pennate diatom Phaeodactylum tricornutum Bohlin possess genes with translated sequences homologous to high-affinity ferric reductases present in model organisms. Thalassiosira pseudonana also possesses putative genes for membrane-bound ferroxidase (TpFET3) and two highly similar iron (Fe) permeases (TpFTR1 and TpFTR2), as well as a divalent metal (M2+) transporter belonging to the NRAMP superfamily (TpNRAMP). In baker's yeast, the ferroxidase,permease complex transports Fe(II) produced by reductases. We investigated transcript abundances of these genes as a function of Fe quota (QFe). Ferric reductase transcripts are abundant in both species (15%,60% of actin) under low QFe and are down-regulated by 5- to 35-fold at high QFe, suggesting Fe(III) reduction is a common, inducible strategy for Fe acquisition in marine diatoms. Permease transcript abundance was regulated by Fe status in T. pseudonana, but we did not detect significant differences in expression of the copper (Cu)-containing ferroxidase. TpNRAMP showed the most dramatic regulation by QFe, suggesting a role in cellular Fe transport in either cell-surface uptake or vacuolar mobilization. We could not identify ferroxidase or permease homologues in the P. tricornutum genome. The up-regulation of genes in T. pseudonana that appear to be missing altogether from P. tricornutum as well as the finding that P. tricornutum seems to have an efficient system to acquire Fe,, suggest that diverse (and uncharacterized) Fe-uptake systems may be at play within diatom assemblages. Different uptake systems among diatoms may provide a mechanistic basis for niche differentiation with respect to Fe availability in the ocean. [source] Development of simple sequence repeat (SSR) markers for the assessment of gene flow and genetic diversity in pigeonpea (Cajanus cajan)MOLECULAR ECOLOGY RESOURCES, Issue 4 2001M. J. Burns Abstract Pigeonpea (Cajanus cajan) is an important subsistence crop in India where traditional landraces and improved hybrids are grown alongside each other. Gene flow may result in genetic erosion of these landraces and their wild relatives, whilst transgene escape from future genetically engineered varieties is another potential hazard. To assess the impact of these factors gene flow needs to be measured. A set of 10 simple sequence repeat markers have been developed, which exhibit polymorphism across a range of pigeonpea varieties. Use of these markers also offers an efficient system for the assessment of genetic diversity within populations of pigeonpea. [source] Signal-to-interference-plus-noise ratio estimation for wireless communication systems: Methods and analysisNAVAL RESEARCH LOGISTICS: AN INTERNATIONAL JOURNAL, Issue 5 2004Daniel R. Jeske Abstract The Signal-to-Interference-plus-Noise Ratio (SINR) is an important metric of wireless communication link quality. SINR estimates have several important applications. These include optimizing the transmit power level for a target quality of service, assisting with handoff decisions and dynamically adapting the data rate for wireless Internet applications. Accurate SINR estimation provides for both a more efficient system and a higher user-perceived quality of service. In this paper, we develop new SINR estimators and compare their mean squared error (MSE) performance. We show that our new estimators dominate estimators that have previously appeared in the literature with respect to MSE. The sequence of transmitted bits in wireless communication systems consists of both pilot bits (which are known both to the transmitter and receiver) and user bits (which are known only by the transmitter). The SINR estimators we consider alternatively depend exclusively on pilot bits, exclusively on user bits, or simultaneously use both pilot and user bits. In addition, we consider estimators that utilize smoothing and feedback mechanisms. Smoothed estimators are motivated by the fact that the interference component of the SINR changes relatively slowly with time, typically with the addition or departure of a user to the system. Feedback estimators are motivated by the fact that receivers typically decode bits correctly with a very high probability, and therefore user bits can be thought of as quasipilot bits. For each estimator discussed, we derive an exact or approximate formula for its MSE. Satterthwaite approximations, noncentral F distributions (singly and doubly) and distribution theory of quadratic forms are the key statistical tools used in developing the MSE formulas. In the case of approximate MSE formulas, we validate their accuracy using simulation techniques. The approximate MSE formulas, of interest in their own right for comparing the quality of the estimators, are also used for optimally combining estimators. In particular, we derive optimal weights for linearly combining an estimator based on pilot bits with an estimator based on user bits. The optimal weights depend on the MSE of the two estimators being combined, and thus the accurate approximate MSE formulas can conveniently be used. The optimal weights also depend on the unknown SINR, and therefore need to be estimated in order to construct a useable combined estimator. The impact on the MSE of the combined estimator due to estimating the weights is examined. © 2004 Wiley Periodicals, Inc. Naval Research Logistics, 2004 [source] Development of an efficient system for the separation of indole alkaloids by high performance liquid chromatography and its applicationsPHYTOCHEMICAL ANALYSIS, Issue 2 2001Irina Gerasimenko Abstract An efficient system for the analysis of indole alkaloids by HPLC on a reversed-phase column using an ion pair technique is described. The optimised chromatographic conditions allowed the successful separation of 22 standard monoterpenoid indole alkaloids (including some isomers) and tryptamine. The described HPLC system was applied to the analysis of alkaloids in intergeneric somatic hybrid cell cultures of Rauvolfia serpentina,×,Rhazya stricta. Copyright © 2001 John Wiley & Sons, Ltd. [source] Fiscal Federalism in AustraliaPUBLIC ADMINISTRATION, Issue 1 2004Iain McLean Australia displays high vertical fiscal imbalance (VFI) for historical and constitutional reasons. It also attempts to achieve the highest degree of horizontal fiscal equalization (HFE) to be found in any democratic federation. The Commonwealth Grants Commission (CGC), a non-partisan body at arm's length from politicians, oversees the regime. A recent report claims that equity, efficiency and transparency would all improve if the regime were abolished. Such a change is politically unachievable, but it raises interesting issues in public finance and public administration, which carry over to other federations and union states. An economically efficient system would: minimize perverse incentives, especially incentives to seek rent; encourage states to grow; discourage suboptimal location decisions; minimize transaction costs. An equitable system would maximize equity between relevantly similar individuals. Aspects of the Australian system that should be copied include the non-partisan agency and the target of HFE between component parts of the country. Aspects that should be discussed and perhaps copied include the very extensive equalization, including the feature of equalizing away the effects of grants for special purposes. Aspects that should probably not be copied include the cumbersome formulae and some of the perverse methods of calculating for ,needs'. All abbreviations and acronyms are spelt out in the Appendix on page 37. [source] Clone differentiation and varietal identification by means of SSR, AFLP, SAMPL and M-AFLP in order to assess the clonal selection of grapevine: the case study of Manto Negro, Callet and Moll, autochthonous cultivars of MajorcaANNALS OF APPLIED BIOLOGY, Issue 2 2010E. Cretazzo Clonal selection is the most worldwide spreading method to improve the performance of wine grapevine (Vitis vinifera) cultivars. In the special case of autochthonous varieties with only local interest, such as Manto Negro, Callet and Moll in Majorca (Spain), good knowledge of their genotypic resources is helpful to assess the development of viticultural and enological potentialities. In this study, 94 vines (including Manto Negro, Callet, Moll and wrongly identified samples) were analysed by means of genetic markers. Several varietal identification mistakes related to the clonal selection in Majorca were detected by the amplification of 33 simple sequence repeats (SSRs) or microsatellite loci, mainly because of the close genetic relationships between Manto Negro, Callet, Moll and other varieties. A very low degree of intravarietal genetic diversity, possibly related to high incidence of virus infections, was shown in all three varieties. However, analysis by amplified fragment length polymorphism (AFLP), selective amplification of microsatellite loci (SAMPL) and microsatellite-amplified fragment length polymorphism (M-AFLP) was suitable for clone genetic discrimination. More than 900 scorable bands were obtained by nine primer combinations. The most efficient system to detect intravarietal genetic differences was M-AFLP, which generated the highest number of polymorphic bands. The use of these markers allowed clustering vines in homogeneous groups, providing essential information about sanitation strategies in order to obtain certified propagation material. [source] Making Markets Work: Modeling Agri-food Systems in TransitionCANADIAN JOURNAL OF AGRICULTURAL ECONOMICS, Issue 2 2001James D. Gaisford Despite a decade of transition, the agri-food sectors of the former command economies consistently underperform relative to their potential. Underproduction and underinvestment are generally observed. This paper develops a model of bilateral monopoly linkages between firms along an agri-food supply chain. In the absence of competitive market forces and an efficient system of commercial law, deficient production and investment should be expected. If the agri-food sectors of the former command economies are to realize their potential, more resources will have to be devoted to reducing the transaction costs associated with broadening markets and enforcing contracts. Bien que dix années aient passé, le secteur agroalimentaire des anciennes économies dirigées ne cesse d'enregistrer un rendement inférieur à celui auquel on pourrait s'attendre. La sous-production et le sous-investissement sont monnaie courante. Les auteurs proposent un modèle reproduisant le monopole bilatéral qui existe entre les entreprises du circuit d'approvisionnement agroalimentaire. En l'absence de concurrence sur le marché et d'un régime efficace de droit commercial, une production et des investissements insuffisants sont inévitables. Pour que le secteur agroalimentaire des anciennes économies centralisées réalise son potentiel, on devra investir plus de ressources afin de réduire les frais de transaction associés à l'élargissement des marchés et de garantir le respect des contrats. [source] Le don d'organes au Canada: I'urgence d'agirCANADIAN PUBLIC ADMINISTRATION/ADMINISTRATION PUBLIQUE DU CANADA, Issue 2 2007René Dussault Sommaire: Le taux de dons d'organes au Canada est l'un des plus faibles parmi tous les pays industrialisés. En 2004, il était de 13 donneurs par million alors qu'on peut espérer, en prenant les mesures appropriées, atteindre dans l'avenir près de 30 donneurs par million. Dans un contexte où la rareté des donneurs potentiels, c'est-à-dire des personnes en état de décès neurologique, est la cause principale d'insuffisance d'organes, il est essentiel que des mesures soient prises pour réduire le plus possible la perte de ces donneurs. Trois raisons expliquent cette perte: les donneurs éventuels ne sont pas bien identifiés, leur famille n'a pas été approchée ou bien elle a refusé le don. Bien que cause importante de la perte de donneurs, le refus des familles n'explique cette situation qu'en partie. Elle découle tout autant d'un manque de formation des professionnels de la santé et de coordination des activités reliées au don et à la transplantation des organes qui présentent un caractère fortement multidisciplinaire et ont un impact important sur la disponibilité des lits de soins intensifs et des salles d'opération. Pourtant, au Canada comme dans tout autre pays, le meilleur moyen de lutter contre le commerce d'organes est d'organiser un système efficace permettant d'augmenter le taux de donneurs effectifs pour répondre à la demande. Nous devons donc porter nos efforts sur l'organisation plus efficace du système de don et de transplantation des organes et travailler sans relâche à réduire la perte de donneurs potentiels, en agissant de manière concertée sur chacune de ses causes. L'adoption du principe du consentement présumé, qui implique de renverser la présomption de droit civil selon laquelle une personne doit donner un consentement éclairé au don de ses organes, ne peut servir de substitut à ce travail d'organisation et de coordination et doit être vue comme un dernier recours. Abstract: The organ donor rate in Canada is one of the lowest among industrialized countries. In 2004, there were thirteen donors per million population; however, if the appropriate measures are taken, this rate may one day reach close to thirty donors per million. In a context where the scarcity of potential donors - persons in a state of neurological death - is without a doubt the major reason for organ shortage, it is essential that measures be taken to minimize the loss of such donors. The three main causes for the loss of donors are the failure to identify potential donors, the failure to approach the family, or the family's refusal to consent to organ donation. Although it is a major reason for the loss of donors, refusal by families to consent to organ donation represents only a small part of the overall picture. Other equally significant factors are the lack of training for health professionals and the lack of coordination with respect to organ donation and organ transplant activities, both of which are highly multidisciplinary in nature and have a considerable impact on the availability of icu beds and operating rooms. In Canada, however, as in any other country, the best way to fight against the trade in human organs is to organize an efficient system to increase the actual donor rate to meet the demand. Therefore, our efforts must focus first and foremost on improving the organization of the organ donation and organ transplant system. We must also work tirelessly to reduce the loss of potential donors through concerted action on each of these issues. Adopting the principle of presumed consent, which implies the overturning of the presumption of civil rights according to which an individual must give his or her informed consent to donate his or her organs, cannot be a substitute for implementing an organized and coordinated system and must be viewed as a last resort under the circumstances. [source] ChemInform Abstract: Direct Amide Synthesis from Either Alcohols or Aldehydes with Amines: Activity of Ru(II) Hydride and Ru(0) Complexes.CHEMINFORM, Issue 36 2010Senthilkumar Muthaiah Abstract The combination of RuH2(PPh3)4 with NHC, MeCN, and NaH provides an efficient system which allows direct synthesis of amides from either alcohols or aldehydes. [source] The Integrated Children's System and disabled childrenCHILD & FAMILY SOCIAL WORK, Issue 3 2008Wendy Mitchell ABSTRACT The Integrated Children's System (ICS) is premised on a single approach to assessment/review, ideally providing a more coherent, comprehensive and efficient system of electronic information recording and sharing among different groups of practitioners. Despite its holistic aims for all children in need, questions have been raised about the use of ICS with certain groups of children, especially those who do not follow normative patterns, such as disabled children. This paper explores the introduction of ICS with disabled children and their families within four pilot authorities in England and Wales. Drawing on interviews and questionnaires with 16 social workers and 22 families experiencing assessment/reviews under the new ICS, this paper suggests that important questions and concerns regarding the appropriateness and usefulness for disabled children of the ICS remain, especially the use of ,standardized' exemplars. Five disability-specific areas of concern are identified, and their implications are considered. [source] Experimental and neural model analysis of styrene removal from polluted air in a biofilterJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 7 2009Eldon R. Rene Abstract BACKGROUND: Biofilters are efficient systems for treating malodorous emissions. The mechanism involved during pollutant transfer and subsequent biotransformation within a biofilm is a complex process. The use of artificial neural networks to model the performance of biofilters using easily measurable state variables appears to be an effective alternative to conventional phenomenological modelling. RESULTS: An artificial neural network model was used to predict the extent of styrene removal in a perlite-biofilter inoculated with a mixed microbial culture. After a 43 day biofilter acclimation period, styrene removal experiments were carried out by subjecting the bioreactor to different flow rates (0.15,0.9 m3 h,1) and concentrations (0.5,17.2 g m,3), that correspond to inlet loading rates up to 1390 g m,3 h,1. During the different phases of continuous biofilter operation, greater than 92% styrene removal was achievable for loading rates up to 250 g m,3 h,1. A back propagation neural network algorithm was applied to model and predict the removal efficiency (%) of this process using inlet concentration (g m,3) and unit flow (h,1) as input variables. The data points were divided into training (115 × 3) and testing set (42 × 3). The most reliable condition for the network was selected by a trial and error approach and by estimating the determination coefficient (R2) value (0.98) achieved during prediction of the testing set. CONCLUSION: The results showed that a simple neural network based model with a topology of 2,4,1 was able to efficiently predict the styrene removal performance in the biofilter. Through sensitivity analysis, the most influential input parameter affecting styrene removal was ascertained to be the flow rate. Copyright © 2009 Society of Chemical Industry [source] Synthesis of mechanical driver and power generation configurations, Part 1: Optimization frameworkAICHE JOURNAL, Issue 9 2010Frank L. Del Nogal Abstract This article presents a novel, systematic, and robust procedure for driver and power plant selection based on mathematical programming. The discrete nature of gas turbines is considered as gas turbine drivers and gas turbine-based power plants are selected from a group of candidates. Plant availability with considering parallel compression has also been included, which allows a more comprehensive exploitation of the trade-offs between capital costs, operating costs, and availability. When neglecting process heating and any steam equipment, the formulation can be applied to heavily power dominated processes, such as LNG. However, a more comprehensive formulation, allowing waste heat recovery and the integration with a multilevel steam system, is also proposed to produce more thermally efficient systems. This approach proved to be flexible and robust and is the first in producing solutions ranging from no-steam to all-steam systems, including all-gas turbine, all-motor and hybrid gas turbine/motor/steam systems. © 2010 American Institute of Chemical Engineers AIChE J, 2010 [source] Interspecific variation in the defensive responses of ant mutualists to plant volatilesBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 2 2008EMILIO M. BRUNA In ant,plant mutualist systems, ants patrol their host plants and search for herbivores. Such patrolling can be inefficient, however, because herbivore activity is spatio-temporally unpredictable. It has been proposed that rapid and efficient systems of communication between ants and plants, such as volatile compounds released following herbivory, both elicit defensive responses and direct workers to sites of herbivore activity. We performed bioassays in which we challenged colonies of two Amazonian plant-ants, Azteca sp. and Pheidole minutula, with extracts of leaf tissue from (1) their respective host-plant species (Tococa bullifera and Maieta guianensis, both Melastomataceae), (2) sympatric ant-plants from the Melastomataceae, and (3) two sympatric but non-myrmecophytic Melastomataceae. We found that ants of both species responded dramatically to host-plant extracts, and that these responses are greater than those to sympatric myrmecophytes. Azteca sp. also responded to non-myrmecophytes with an intensity similar to that of sympatric ant-plants. By contrast, the response of P. minutula to any non-myrmecophytic extracts was limited. These differences may be driven in part by interspecific differences in nesting behaviour; although P. minutula only nests in host plants, Azteca sp. will establish carton satellite nests on nearby plants. We hypothesize that Azteca sp. must therefore recognize and defend a wider array of species than P. minutula. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 94, 241,249. [source] Plant-produced human growth hormone shows biological activity in a rat modelBIOTECHNOLOGY PROGRESS, Issue 2 2009Shailaja Rabindran Abstract Plants have been shown to be efficient systems for expressing a wide range of recombinant proteins from various origins. Here, using a plant virus-based expression vector to produce human growth hormone (hGH) in Nicotiana benthamiana plants, we demonstrate, for the first time, that the plant-produced hGH (pphGH) is biologically active in a hypophysectomized rat model. We observed an average weight gain of ,17 g per animal in a group of 10 animals that were injected subcutaneously with pphGH with 60 ,g/dose for 10 days. With the increasing demand for hGH, accompanied with the need to make this recombinant protein available to a wider population at a more reasonable cost, plants provide a feasible alternative to current production platforms. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 [source] | |||||||||||||||||||