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Similar Efficiency (similar + efficiency)
Selected AbstractsGuanine-Based Biogenic Photonic-Crystal Arrays in Fish and SpidersADVANCED FUNCTIONAL MATERIALS, Issue 2 2010Avital Levy-Lior Abstract Biological photonic systems composed of anhydrous guanine crystals evolved separately in several taxonomic groups. Here, two such systems found in fish and spiders, both of which make use of anhydrous guanine crystal plates to produce structural colors, are examined. Measurements of the photonic-crystal structures using cryo-SEM show that the crystal plates in both fish skin and spider integument are ,20-nm thick. The reflective unit in the fish comprises stacks of single plates alternating with ,230-nm-thick cytoplasm layers. In the spiders the plates are formed as doublet crystals, cemented by 30-nm layers of amorphous guanine, and are stacked with ,200,nm of cytoplasm between crystal doublets. They achieve light reflective properties through the control of crystal morphology and stack dimensions, reaching similar efficiencies of light reflectivity in both fish skin and spider integument. The structure of guanine plates in spiders are compared with the more common situation in which guanine occurs in the form of relatively unorganized prismatic crystals, yielding a matt white coloration. [source] Organic fertilizers derived from plant materials Part II: Turnover in field trialsJOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 2 2006Torsten Müller Abstract Our aim was to investigate two different organic fertilizers derived from plant materials (OFDP) with respect to their nitrogen (N) and carbon (C) turnover in field trials planted with small radish (Raphanus sativus L. var. sativus) and white cabbage (Brassica oleracea L. convar. capitata var. alba) or fallow. The two fertilizers investigated were coarse seed meal of yellow lupin (Lupinus luteus L.) and coarse meal of castor cake (Ricinus communis L.). Under cool spring conditions, the soil turnover of yellow lupin,seed meal was slightly enhanced compared to castor-cake meal. During the vegetation period of the vegetables, N added with both fertilizers was metabolized more or less completely by soil microorganisms. Due to similar efficiencies of the fertilizers tested, no significant difference could be found in the N uptake of plants. From this point of view, yellow lupin,seed meal, which can be produced by farmers themselves, has the potential to replace the widely used castor-cake meal. Considerable amounts of N may remain in the field after fertilization with OFDPs either as mineral N or as easily mineralizable organic N. This N should be utilized immediately by a succeeding crop to avoid leaching losses. [source] Anti-tumor activity of mesenchymal stem cells producing IL-12 in a mouse melanoma modelEXPERIMENTAL DERMATOLOGY, Issue 11 2006Lina Elzaouk Abstract:, Mesenchymal stem cells (MSCs) represent a new tool for delivery of therapeutic agents to tumor cells. In this study, we have evaluated the anti-tumor activity of human MSCs stably transduced with a retroviral vector expressing the cytokine interleukin-12 (IL-12) in a mouse melanoma model. Application of MSC(IL-12) but not control MSCs strongly reduced the formation of lung metastases of B16F10 melanoma cells. The activity of the MSC(IL-12) cells was dependent on the presence of natural killer (NK) cells in this experimental setting. Further, MSC(IL-12) cells elicited a pronounced retardation of tumor growth and led to prolonged survival when injected into established subcutaneous melanoma in a therapeutic regimen. The therapeutic effect of the MSC(IL-12) was in part mediated by CD8+ T cells, while NK cells and CD4+ T cells appeared to play a minor role. The anti-tumor effect of MSC(IL-12) cells was of similar efficiency as observed for application of naked plasmid DNA encoding IL-12. The presented data demonstrate that these two different strategies can induce a similar therapeutic anti-tumor efficacy in the mouse melanoma tumor model. [source] Financial Costs of Alcoholism Treatment Programs: A Longitudinal and Comparative Evaluation Among Four Specialized CentersALCOHOLISM, Issue 1 2003B. Nalpas Background: Alcoholism is a worldwide problem. Many strategies for alcohol detoxification and relapse prevention exist, but each alcohol treatment center has its own program. The objective of this study was to analyze and compare the financial cost and effectiveness of alcohol treatment programs from inpatient stay to follow-up 1 year later. This was a prospective, open, nonrandomized study of 4 specialized alcohol treatment centers and 267 patients admitted for alcohol detoxification. Methods: We recorded all medical and nonmedical interventions related to the program during patient stay in the hospital and every 3 months after discharge for 1 year and recorded the occurrence of alcohol relapse. Financial evaluation was based on the prices of refund from the French national health insurance service. Results: The mean cost of hospitalization ranged from ,1326 to ,1917 (p= 0.001), a variation mainly due to the difference in the length of hospital stay but also to the cost of the inpatient program, routine medical checkups, and drugs administered. The mean cost of 1 year of follow-up per patient ranged from ,419 to ,1704 (p= 0.001). The efficiency, corresponding to the money spent to prevent the relapse of one patient during 1 month, was approximately ,500/month in three centers and ,658 in the fourth. However, for a similar efficiency, the effectiveness, assessed by the mean time without relapse, was significantly (p= 0.001) different; center 1, which had the highest total cost, had an effectiveness 1.56 times higher than center 3, which had the lowest cost. Conclusions: This work emphasizes the heterogeneity of the costs and effectiveness of alcoholism treatment programs and suggests that research should be conducted to determine which program is the most rational, cost-efficient, and beneficial for patients and the public health office economy. [source] A Cre::FLP fusion protein recombines FRT or loxP sites in transgenic maize plants,PLANT BIOTECHNOLOGY JOURNAL, Issue 8 2008Vesna Djukanovic Summary The coding sequences of Cre (site-specific recombinase from bacteriophage P1) and FLP (yeast 2-µm plasmid site-specific recombinase) were fused in frame to produce a novel, dual-function, site-specific recombinase gene. Transgenic maize plants containing the Cre::FLP fusion expression vector were crossed to transgenic plants containing either the loxP or FRT excision substrate. Complete and precise excisions of chromosomal fragments flanked by the respective target sites were observed in the F1 and F2 progeny plants. The episomal DNA recombination products were frequently lost. Non-recombined FRT substrates found in the F1 plants were recovered in the F2 generation after the Cre::FLP gene segregated out. They produced the recombination products in the F3 generation when crossed back to the FLP-expressing plants. These observations may indicate that the efficiency of site-specific recombination is affected by the plant developmental stage, with site-specific recombination being more prevalent in developing embryos. The Cre::FLP fusion protein was also tested for excisions catalysed by Cre. Excisions were identified in the F1 plants and verified in the F2 plants by polymerase chain reaction and Southern blotting. Both components of the fusion protein (FLP and Cre) were functional and acted with similar efficiency. The crossing strategy proved to be suitable for the genetic engineering of maize using the FLP or Cre site-specific recombination system. [source] Third generation photovoltaics: Ultra-high conversion efficiency at low costPROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 2 2001Martin A. GreenArticle first published online: 5 APR 200 Since the early days of terrestrial photovoltaics, a common perception has been that ,first generation' silicon wafer-based solar cells eventually would be replaced by a ,second generation' of lower cost thin-film technology, probably also involving a different semiconductor. Historically, cadmium sulphide, amorphous silicon, copper indium diselenide, cadmium telluride and now thin-film polycrystalline silicon have been regarded as key thin-film candidates. Any mature solar cell technology seems likely to evolve to the stage where costs are dominated by those of the constituent materials, be they silicon wafers or glass sheet. It is argued, therefore, that photovoltaics is likely to evolve, in its most mature form, to a ,third generation' of high-efficiency thin-film technology. By high efficiency, what is meant is energy conversion values double or triple the 15,20% range presently targeted, closer to the thermodynamic limit of 93%. Tandem cells are the best known of such high-efficiency approaches, where efficiency can be increased merely by adding more cells of different bandgap to a cell stack, at the expense of increased complexity and spectral sensitivity. However, a range of other more ,paralleled' approaches offer similar efficiency to an infinite stack of tandem cells. These options are reviewed together with possible approaches for practical implementation, likely to become more feasible with the evolution of materials technology over the next two decades. Copyright © 2001 John Wiley & Sons, Ltd. [source] Pharmacological characterization of F-180: a selective human V1a vasopressin receptor agonist of high affinityBRITISH JOURNAL OF PHARMACOLOGY, Issue 7 2002Miriam Andrés The pharmacological properties of F-180, a vasopressin (VP) structural analogue, were determined on CHO cells expressing the different human vasopressin and oxytocin (OT) receptor subtypes. Binding experiments revealed that F-180 exhibited a high affinity for the human V1a receptor subtype (Ki=11 nM) and was selective for this receptor subtype. Functional studies performed on CHO cells expressing human V1a receptors indicate that similarly to AVP, F-180 can stimulate the accumulation of inositol phosphate. The activation constant (Kact) for both F-180 and AVP was 1.7 nM. F-180 was also an agonist for the human V2 and V1b receptor subtypes and an antagonist for the human OT receptor. Since marked species pharmacological differences for vasopressin receptors have been described, we studied the properties of F-180 on various mammalian species. F-180 showed high affinity and good selectivity for human and bovine V1a receptors, but weak affinity and non selective properties for rat V1a receptors. To assess the functional properties of F-180 on a native biological model, we performed studies on primary cultures of cells from bovine zona fasciculata (ZF). As AVP, F-180 stimulated inositol phosphate accumulation and cortisol secretion with similar efficiency. In conclusion, we demonstrate that F-180 is the first selective V1a agonist described for human and bovine vasopressin receptors. Therefore F-180 can be used as a powerful pharmacological tool to characterize the actions of vasopressin that are mediated by V1a receptor subtypes. British Journal of Pharmacology (2002) 135, 1828,1836; doi:10.1038/sj.bjp.0704634 [source] | ||||||||||