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Sample records for optimum non-toxic concentrations

  1. Long-term exposure of CdTe quantum dots on PC12 cellular activity and the determination of optimum non-toxic concentrations for biological use

    Directory of Open Access Journals (Sweden)

    Gérard Valérie A

    2010-03-01

    Full Text Available Abstract Background The unique and tuneable photonic properties of Quantum Dots (QDs have made them potentially useful tools for imaging biological entities. However, QDs though attractive diagnostic and therapeutic tools, have a major disadvantage due to their inherent cytotoxic nature. The cellular interaction, uptake and resultant toxic influence of CdTe QDs (gelatinised and non-gelatinised Thioglycolic acid (TGA capped have been investigated with pheochromocytoma 12 (PC12 cells. In conjunction to their analysis by confocal microscopy, the QD - cell interplay was explored as the QD concentrations were varied over extended (up to 72 hours co-incubation times. Coupled to this investigation, cell viability, DNA quantification and cell proliferation assays were also performed to compare and contrast the various factors leading to cell stress and ultimately death. Results Thioglycolic acid (TGA stabilised CdTe QDs (gel and non - gel were co-incubated with PC12 cells and investigated as to how their presence influenced cell behaviour and function. Cell morphology was analysed as the QD concentrations were varied over co-incubations up to 72 hours. The QDs were found to be excellent fluorophores, illuminating the cytoplasm of the cells and no deleterious effects were witnessed at concentrations of ~10-9 M. Three assays were utilised to probe how individual cell functions (viability, DNA quantification and proliferation were affected by the presence of the QDs at various concentrations and incubation times. Cell response was found to not only be concentration dependant but also influenced by the surface environment of the QDs. Gelatine capping on the surface acts as a barrier towards the leaking of toxic atoms, thus reducing the negative impact of the QDs. Conclusion This study has shown that under the correct conditions, QDs can be routinely used for the imaging of PC12 cells with minimal adverse effects. We have found that PC12 cells are highly

  2. Long-term exposure of CdTe quantum dots on PC12 cellular activity and the determination of optimum non-toxic concentrations for biological use

    LENUS (Irish Health Repository)

    Prasad, Babu R

    2010-03-25

    Abstract Background The unique and tuneable photonic properties of Quantum Dots (QDs) have made them potentially useful tools for imaging biological entities. However, QDs though attractive diagnostic and therapeutic tools, have a major disadvantage due to their inherent cytotoxic nature. The cellular interaction, uptake and resultant toxic influence of CdTe QDs (gelatinised and non-gelatinised Thioglycolic acid (TGA) capped) have been investigated with pheochromocytoma 12 (PC12) cells. In conjunction to their analysis by confocal microscopy, the QD - cell interplay was explored as the QD concentrations were varied over extended (up to 72 hours) co-incubation times. Coupled to this investigation, cell viability, DNA quantification and cell proliferation assays were also performed to compare and contrast the various factors leading to cell stress and ultimately death. Results Thioglycolic acid (TGA) stabilised CdTe QDs (gel and non - gel) were co-incubated with PC12 cells and investigated as to how their presence influenced cell behaviour and function. Cell morphology was analysed as the QD concentrations were varied over co-incubations up to 72 hours. The QDs were found to be excellent fluorophores, illuminating the cytoplasm of the cells and no deleterious effects were witnessed at concentrations of ~10-9 M. Three assays were utilised to probe how individual cell functions (viability, DNA quantification and proliferation) were affected by the presence of the QDs at various concentrations and incubation times. Cell response was found to not only be concentration dependant but also influenced by the surface environment of the QDs. Gelatine capping on the surface acts as a barrier towards the leaking of toxic atoms, thus reducing the negative impact of the QDs. Conclusion This study has shown that under the correct conditions, QDs can be routinely used for the imaging of PC12 cells with minimal adverse effects. We have found that PC12 cells are highly susceptible to

  3. Optimum sizing of steam turbines for concentrated solar power plants

    OpenAIRE

    Andreas Poullikkas, Constantinos Rouvas, Ioannis Hadjipaschalis, George Kourtis

    2012-01-01

    In this work, a selection of the optimum steam turbine type and size for integration in concentrated solar power (CSP) plants is carried out. In particular, the optimum steam turbine input and output interfaces for a range of CSP plant capacity sizes are identified. Also, efficiency and electricity unit cost curves for various steam turbine capacities are estimated by using a combination of the Steam Pro software module of the Thermoflow Suite 18 package and the IPP v2.1 optimization software...

  4. High concentrations of protein test substances may have non-toxic effects on Daphnia magna: implications for regulatory study designs and ecological risk assessments for GM crops.

    Science.gov (United States)

    Raybould, Alan; Burns, Andrea; Hamer, Mick

    2014-01-01

    Laboratory testing for possible adverse effects of insecticidal proteins on non-target organisms (NTOs) is an important part of many ecological risk assessments for regulatory decision-making about the cultivation of insect-resistant genetically modified (IRGM) crops. To increase confidence in the risk assessments, regulatory guidelines for effects testing specify that representative surrogate species for NTOs are exposed to concentrations of insecticidal proteins that are in excess of worst-case predicted exposures in the field. High concentrations in effects tests are achieved by using protein test substances produced in microbes, such as Escherichia coli. In a study that exposed Daphnia magna to a single high concentration of a microbial test substance containing Vip3Aa20, the insecticidal protein in MIR162 maize, small reductions in growth were observed. These effects were surprising as many other studies strongly suggest that the activity of Vip3Aa20 is limited to Lepidoptera. A plausible explanation for the effect on growth is that high concentrations of test substance have a non-toxic effect on Daphnia, perhaps by reducing its feeding rate. A follow-up study tested that hypothesis by exposing D. magna to several concentrations of Vip3Aa20, and a high concentration of a non-toxic protein, bovine serum albumin (BSA). Vip3Aa20 and BSA had sporadic effects on the reproduction and growth of D. magna. The pattern of the effects suggests that they result from non-toxic effects of high concentrations of protein, and not from toxicity. The implications of these results for regulatory NTO effects testing and ERA of IRGM crops are discussed.

  5. High concentrations of protein test substances may have non-toxic effects on Daphnia magna: Implications for regulatory study designs and ecological risk assessments for GM crops

    Science.gov (United States)

    Raybould, Alan; Burns, Andrea; Hamer, Mick

    2014-01-01

    Laboratory testing for possible adverse effects of insecticidal proteins on non-target organisms (NTOs) is an important part of many ecological risk assessments for regulatory decision-making about the cultivation of insect-resistant genetically modified (IRGM) crops. To increase confidence in the risk assessments, regulatory guidelines for effects testing specify that representative surrogate species for NTOs are exposed to concentrations of insecticidal proteins that are in excess of worst-case predicted exposures in the field. High concentrations in effects tests are achieved by using protein test substances produced in microbes, such as Escherichia coli. In a study that exposed Daphnia magna to a single high concentration of a microbial test substance containing Vip3Aa20, the insecticidal protein in MIR162 maize, small reductions in growth were observed. These effects were surprising as many other studies strongly suggest that the activity of Vip3Aa20 is limited to Lepidoptera. A plausible explanation for the effect on growth is that high concentrations of test substance have a non-toxic effect on Daphnia, perhaps by reducing its feeding rate. A follow-up study tested that hypothesis by exposing D. magna to several concentrations of Vip3Aa20, and a high concentration of a non-toxic protein, bovine serum albumin (BSA). Vip3Aa20 and BSA had sporadic effects on the reproduction and growth of D. magna. The pattern of the effects suggests that they result from non-toxic effects of high concentrations of protein, and not from toxicity. The implications of these results for regulatory NTO effects testing and ERA of IRGM crops are discussed. PMID:25523175

  6. The potentiation effect makes the difference: Non-toxic concentrations of ZnO nanoparticles enhance Cu nanoparticle toxicity in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Li, Lingxiangyu [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); Fernández-Cruz, María Luisa; Connolly, Mona [Departamento de Medio Ambiente, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Madrid 28040 (Spain); Conde, Estefanía; Fernández, Marta [Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Madrid 28040 (Spain); Schuster, Michael [Department of Chemistry, Technische Universität München, Garching 85747 (Germany); Navas, José María, E-mail: jmnavas@inia.es [Departamento de Medio Ambiente, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Madrid 28040 (Spain)

    2015-02-01

    Here we examined whether the addition of a non-toxic concentration (6.25 μg/mL) of zinc oxide nanoparticles (ZnONPs: 19, 35 and 57 nm, respectively) modulates the cytotoxicity of copper nanoparticles (CuNPs, 63 nm in size) in the human hepatoma cell line HepG2. The cytotoxic effect of CuNPs on HepG2 cells was markedly enhanced by the ZnONPs, the largest ZnONPs causing the highest increase in toxicity. However, CuNPs cytotoxicity was not affected by co-incubation with medium containing only zinc ions, indicating the increase in toxicity might be attributed to the particle form of ZnONPs. Transmission electron microscopy (TEM) revealed the presence of CuNPs and ZnONPs inside the cells co-exposed to both types of NP and outflow of cytoplasm through the damaged cell membrane. Inductively coupled plasma mass spectrometry (ICP-MS) determined an increase in the concentration of zinc and a decrease in that of copper in co-exposed cells. On the basis of these results, we propose that accumulation of large numbers of ZnONPs in the cells alters cellular membranes and the cytotoxicity of CuNPs is increased. - Highlights: • ZnONPs at non-toxic concentrations increased the toxicity of CuNPs in vitro. • ZnONPs of larger size provoked a stronger synergistic effect with CuNPs. • The synergistic effect was attributed to the particle fraction of ZnONPs.

  7. Optimum sizing of steam turbines for concentrated solar power plants

    Directory of Open Access Journals (Sweden)

    Andreas Poullikkas, Constantinos Rouvas, Ioannis Hadjipaschalis, George Kourtis

    2012-01-01

    Full Text Available In this work, a selection of the optimum steam turbine type and size for integration in concentrated solar power (CSP plants is carried out. In particular, the optimum steam turbine input and output interfaces for a range of CSP plant capacity sizes are identified. Also, efficiency and electricity unit cost curves for various steam turbine capacities are estimated by using a combination of the Steam Pro software module of the Thermoflow Suite 18 package and the IPP v2.1 optimization software tool. The results indicate that the estimated efficiency and the expected specific capital cost of the power block are very important criteria in choosing the best steam turbine size of a CSP plant. For capacity sizes of 10kWe up to 50MWe, the steam turbine efficiency increases and the steam turbine expected specific capital cost of the power block decreases at a high rate, whereas for larger sizes they remain almost constant. Thus, there is significant efficiency gains to be realized and large cost savings in increasing the turbine size up to 50MWe. Finally, although the cost of electricity of a CSP plant with capacities greater than 1MWe is significantly reduced to less than 1US$/kWh, currently such technology can only become economically viable through supporting schemes.

  8. Optimum sizing of steam turbines for concentrated solar power plants

    Energy Technology Data Exchange (ETDEWEB)

    Poullikkas, Andreas; Rouvas, Constantinos; Hadjipaschalis, Ioannis; Kourtis, Gorge [Electricity Authority of Cyprus, P.O. Box 24506, 1399 Nicosia (Cyprus)

    2012-07-01

    In this work, a selection of the optimum steam turbine type and size for integration in concentrated solar power (CSP) plants is carried out. In particular, the optimum steam turbine input and output interfaces for a range of CSP plant capacity sizes are identified. Also, efficiency and electricity unit cost curves for various steam turbine capacities are estimated by using a combination of the Steam Pro software module of the Thermoflow Suite 18 package and the IPP v2.1 optimization software tool. The results indicate that the estimated efficiency and the expected specific capital cost of the power block are very important criteria in choosing the best steam turbine size of a CSP plant. For capacity sizes of 10kWe up to 50MWe, the steam turbine efficiency increases and the steam turbine expected specific capital cost of the power block decreases at a high rate, whereas for larger sizes they remain almost constant. Thus, there is significant efficiency gains to be realized and large cost savings in increasing the turbine size up to 50MWe. Finally, although the cost of electricity of a CSP plant with capacities greater than 1MWe is significantly reduced to less than 1US$/kWh, currently such technology can only become economically viable through supporting schemes.

  9. The potentiation effect makes the difference: non-toxic concentrations of ZnO nanoparticles enhance Cu nanoparticle toxicity in vitro.

    Science.gov (United States)

    Li, Lingxiangyu; Fernández-Cruz, María Luisa; Connolly, Mona; Conde, Estefanía; Fernández, Marta; Schuster, Michael; Navas, José María

    2015-02-01

    Here we examined whether the addition of a non-toxic concentration (6.25 μg/mL) of zinc oxide nanoparticles (ZnONPs: 19, 35 and 57 nm, respectively) modulates the cytotoxicity of copper nanoparticles (CuNPs, 63 nm in size) in the human hepatoma cell line HepG2. The cytotoxic effect of CuNPs on HepG2 cells was markedly enhanced by the ZnONPs, the largest ZnONPs causing the highest increase in toxicity. However, CuNPs cytotoxicity was not affected by co-incubation with medium containing only zinc ions, indicating the increase in toxicity might be attributed to the particle form of ZnONPs. Transmission electron microscopy (TEM) revealed the presence of CuNPs and ZnONPs inside the cells co-exposed to both types of NP and outflow of cytoplasm through the damaged cell membrane. Inductively coupled plasma mass spectrometry (ICP-MS) determined an increase in the concentration of zinc and a decrease in that of copper in co-exposed cells. On the basis of these results, we propose that accumulation of large numbers of ZnONPs in the cells alters cellular membranes and the cytotoxicity of CuNPs is increased.

  10. Optimum Design Of Grid Connected Photovoltaic System Using Concentrators

    Directory of Open Access Journals (Sweden)

    Eng. Mohammed Fawzy

    2015-08-01

    Full Text Available Abstract Due to the increasing demand of electrical energy in Egypt and also in many neighboring countries around the world the main problem facing electrical energy production using classical methods such steam power stations is the depletion of fossil fuels. The gap between the electrical energy demand and the continuous increase on the fossil fuel cost make the problem of electricity generation more sophisticated. With the continuous decrease of the photovoltaic PV technologies cost it doesnt make sense neglecting the importance of electricity production using solar photovoltaic PV especially that the annual average daily energy received is about 6 kamp12310whmamp123112day in Cairo Egypt 30N.In this work a detailed simulation model including photovoltaic PV module characteristics and climatic conditions of Cairo Egypt is developed. The model compares fixed PV systems electrical energy output with photovoltaic PV system using concentrators and double axis tracker systems. The comparison includes the energy generated area required as well as the cost per kwh generated. The optimality criterion is the cost per kwh generated. The system that gives the minimum cost per kwh is the optimum system. To verify the developed model the simulation results of fixed PV modules and CPV using tracking system obtained by the model are compared with practical measurements of 40KW peak station erected in Cairo Egypt 30N.Very good agreement between measured values and results obtained from detailed simulation model. For fixed PV system the detailed economic analysis showed that it gives minimum cost perkwh generated Comparisons among these systems are presented. For Cairo results showed that a cost of about 6 to 9 US centskwh is attainable.

  11. Radioiodine treatment for non-toxic goitre

    DEFF Research Database (Denmark)

    Feldt-Rasmussen, Ulla

    2009-01-01

    There is no ideal treatment for benign multinodular goitre. Besides surgery, which is recommended for large goitres or when malignancy cannot be excluded, the non-surgical treatment options are levothyroxine therapy and radioiodine ((131)I) therapy. Conventional (131)I therapy [without recombinant...... human thyroid-stimulating hormone (rhTSH)] has been used for more than a decade in symptomatic non-toxic multinodular goitre, and although it does lead to significant thyroid volume reduction, relatively high activities of radioiodine are needed because of a frequent finding of a low thyroid radioiodine...... in multinodular goitre, aspects of this association, such as the cost-benefit and optimum rhTSH dose and safety, will have to be sufficiently clarified....

  12. Determination of optimum sunlight concentration level in space for 3-4 cascade solar cells

    Science.gov (United States)

    Curtis, H. B.

    1982-01-01

    The optimum range of concentration in space for III-V cascade cells has been calculated using a realistic solar cell diode equation. Temperature was varied with concentration using several models and ranged from 55 deg at one sun to between 80 deg and 200 deg C at 100 suns. A variety of series resistance and internal resistances were used. Coefficients of the diffusion and recombination terms are strongly temperature dependent. The study indicates that the maximum efficiency of 30 percent occurs in the 50 to 100 X sun concentration range provided series resistance is below 0.015 ohm sq cm and cell temperature is about 80 C at 100 suns.

  13. Determination of optimum sunlight concentration level in space for 3-5 cascade solar cells

    Science.gov (United States)

    Curtis, H. B.

    1982-01-01

    The optimum range of concentration levels in space for III-V cascade cells was calculated using a realistic solar cell diode equation. Temperature was varied with concentration using several models and ranged from 55 C at 1 sun to between 80 and 200 C at 100 suns. A variety of series resistance and internal resistances were used. Coefficients of the diffusion and recombination terms are strongly temperature dependent. The study indicates that the maximum efficiency of 30 percent occurs in the 50 to 100 sun concentration range provided series resistance is below 0.015 ohm-sq cm and cell temperature is about 80 C at 100 suns.

  14. MECHANICAL STRENGTH ENHANCEMENT OF OPEN-CELL ALUMINA FOAMS USING OPTIMUM CONCENTRATION OF DEFLOCCULANT

    Directory of Open Access Journals (Sweden)

    A. Hadi

    2015-06-01

    Full Text Available Open-cell alumina foams were prepared using the appropriate alumina slurry and polyurethane sponge with linear pore density of approximately 14 pores per inch (ppi as a template by the replica method. The rheological studies showed that the optimum solid content for the slurries without deflocculants was 60 wt. %. In order to increase the slurry solid content, Tiron (1,2-dihydroxy-3,5-benzene disulfonic acid disodium salt was used as dispersant. To determine the optimum concentration of dispersant, the viscosity curves of alumina slurries containing different values of Tiron from 0 to 1.2 wt. % (based on dry material weight were studied. The optimum concentration of Tiron obtained for lowest viscosity was 0.8 wt. %. Thus, the solid content in the slurry could be increased from 60 to 66 wt. %. The effect of increase in the slurry solid content and the way it affects the foam structure and the mechanical strength were investigated. Microstructural observations of the foams show a significant reduction in macroscopic and microscopic defects in the foam struts when the slurry solid content is increased. Total porosity of the produced alumina foams prepared using slurries containing 60 and 66 wt. % solid are 83.3 and 80.4 %, respectively, while the compressive strength of the foams has increased from 1.33 to 3.24 MPa.

  15. Optimum Concentration Ratio Analysis Using Dynamic Thermal Model for Concentrated Photovoltaic System

    Science.gov (United States)

    2012-03-22

    hplate = Hsil/tau_H ; Pc = hplate*(A)*(T-Tstream) ;% convective cooling of the cell by the ambient air % as it stands now, Pc remains constant...Iberoamericano de Estudiantes de Ingenieria Electrica, s.l. : Cibelec, 2005. 40. Brogren, Maria. Optical Effeciency of Low-Concentrating Solar Energy

  16. Non-Toxic HAN Monopropellant Propulsion Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Non-toxic monopropellants have been developed that provide better performance than toxic hydrazine. Formulations based on hydroxylammonium nitrate (HAN) have...

  17. Non-Toxic HAN Monopropellant Propulsion Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Non-toxic monopropellants have been developed that provide better performance than toxic hydrazine. Formulations based on hydroxylammonium nitrate (HAN) have...

  18. Effect of soybean aging on the quality of soymilk, firmness of tofu and optimum coagulant concentration.

    Science.gov (United States)

    Kamizake, N K K; Silva, L C P; Prudencio, S H

    2016-01-01

    This study investigated the influence of soybean aging (cultivars Coodetec 214 and BRS 267) on the physicochemical properties of soymilk and tofu. Two aging conditions were adopted: accelerated aging (84% relative humidity and 30 °C, up to 9 months) and natural aging (ambient temperature and relative humidity, up to 18 months) and a control condition (47% relative humidity, -20 °C). Tofu was coagulated with MgSO4. Optimum coagulant concentration (OCC) decreased with increasing coagulation temperature and soybean aging time. OCC showed positive correlation with total solids, protein, ash, Ca, Mg and P contents of soymilk. The products showed, in general, reduced color parameters (L(∗) and h°), proteins, lipids, carbohydrates, ash, Ca, Mg, P and total solids (except in the tofu) and firmness (tofu) with increasing aging time. Tofu yields decreased with accelerated aging time.

  19. Optimum iodine concentration of contrast material through microcatheters: hydrodynamic analysis of experimental results

    Science.gov (United States)

    Yamauchi, Teiyu; Furui, Shigeru; Harasawa, Arimi; Ishimura, Makoto; Imai, Tatsuhiko; Hayashi, Toshimitsu

    2002-07-01

    It is important to increase the iodine delivery rate (I), that is the iodine concentration of the contrast material (C) × the flow rate of the contrast material (Q), through a catheter to obtain high quality arteriograms. The iodine delivery rate varies depending on the iodine concentration of the contrast material. The purpose of this study is to estimate the optimum iodine concentration (Copt) of contrast material (i.e. the iodine concentration at which I becomes maximum) through a microcatheter of a given length (L), inner diameter (D) and injection pressure (P). Iohexol, ioversol and iopamidol of 11-12 iodine concentrations (140-350, 160-350 or 160-370 mg cm-3) at 37 °C are used. I and Reynolds number (Re) of the flow of each contrast material through four microcatheters (0.49-0.68 mm in inner diameter, 1000-1500 mm in length) at injection pressures of 1.38, 2.76, 4.14 and 5.52 × 106 Pa (200, 400, 600 and 800 pounds per square inch) are obtained experimentally. The relationships between I and C and between I and Re are examined for each catheter and injection pressure. Copt is 160-280 mg cm-3 for iohexol, 180-280 mg cm-3 for ioversol and 200-300 mg cm-3 for iopamidol. I becomes maximum when Re approximates the critical Reynolds number (Re ≃ 2300). Utilizing this principle, we can estimate Copt and its flow rate through a microcatheter of a given L, D and P.

  20. Real-time texture analysis for identifying optimum microbubble concentration in 2-D ultrasonic particle image velocimetry.

    Science.gov (United States)

    Niu, Lili; Qian, Ming; Yan, Liang; Yu, Wentao; Jiang, Bo; Jin, Qiaofeng; Wang, Yanping; Shandas, Robin; Liu, Xin; Zheng, Hairong

    2011-08-01

    Many recent studies on ultrasonic particle image velocimetry (Echo PIV) showed that the accuracy of two-dimensional (2-D) flow velocity measured depends largely on the concentration of ultrasound contrast agents (UCAs) during imaging. This article presents a texture-based method for identifying the optimum microbubble concentration for Echo PIV measurements in real-time. The texture features, standard deviation of gray level, and contrast, energy and homogeneity of gray level co-occurrence matrix were extracted from ultrasound contrast images of rotational and pulsatile flow (10 MHz) in vitro and in vivo mouse common carotid arterial flow (40 MHz) with UCAs at various concentrations. The results showed that, at concentration of 0.8∼2 × 10³ bubbles/mL in vitro and 1∼5 × 10⁵ bubbles/mL in vivo, image texture features had a peak value or trough value, and velocity vectors with high accuracy can be obtained. Otherwise, poor quality velocity vectors were obtained. When the texture features were used as a feature set, the accuracy of K-nearest neighbor classifier can reach 86.4% in vitro and 87.5% in vivo, respectively. The texture-based method is shown to be able to quickly identify the optimum microbubble concentration and improve the accuracy for Echo PIV imaging.

  1. What is the optimum concentration of m-cresol in antivenoms?

    Directory of Open Access Journals (Sweden)

    MA Abd-Elsalam

    2011-01-01

    Full Text Available Antivenoms against snake and scorpion envenomations are usually equine in nature and composed mostly of F(ab'2; additionally, phenol and m-cresol are mainly employed for their preservation. Although there is no study on this subject, m-cresol is utilized by most manufacturers in a concentration that ranges from 0.15 to 0.35 g%. Decreasing the concentration of m-cresol to its minimal effective level may protect victims from its toxic effects and keep the antivenom stable during its shelf life without forming any aggregates. In the present work, different concentrations of m-cresol, ranging from 0.1 to 0.35 g%, were used with some selected batches of snake and scorpion antivenoms. A low concentration of 0.15 g% showed an acceptable preserving result that complies perfectly with antimicrobial specifications stated by the British Pharmacopoeia. Tested antivenoms (in 12 batches, when kept in a cold room for 39 months (more than their shelf life, retained their physical, chemical and microbiological activities according to the specifications of pharmacopeias. The present data demonstrated that reduction of m-cresol concentration to 0.15 g% in case of equine F(ab'2 antivenoms will improve safety of such preparations and preserve their stability during their shelf life.

  2. Optimum Concentrations of Trichoderma longibrachiatum and Cadusafos for Controlling Meloidogyne javanica on Zucchini Plants.

    Science.gov (United States)

    Sokhandani, Zahra; Moosavi, Mohammad Reza; Basirnia, Tahereh

    2016-03-01

    A factorial experiment was established in a completely randomized design to verify the effect of different inoculum levels of an Iranian isolate of Trichoderma longibrachiatum separately and in combination with various concentrations of cadusafos against Meloidogyne javanica in the greenhouse. Zucchini seeds were soaked for 12 hr in five densities (0, 10(5), 10(6), 10(7), and 10(8) spores/ml suspension) of the fungus prior to planting in pots containing four concentrations of cadusafos (0, 0.5, 1, and 2 mg a.i./kg soil). The data were analyzed using a custom response surface regression model and the response surface curve and contour plots were drawn. Reliability of the model was examined by comparing the result of new experimental treatments with the predicted results. The optimal levels of these two variables also were calculated. The interactive effects of concentrations of Trichoderma and cadusafos were insignificant for several responses such as the total number of eggs per gram soil, the number of intact eggs per gram soil, nematode reproduction factor, and control percent. Closeness of experimental mean values with the expected values proved the validity of the model. The optimal levels of the cadusafos concentration and Trichoderma concentration that caused the best plant growth and lowest nematode reproduction were 1.7 mg a.i./kg soil and 10(8) conidia/ml suspension, respectively.

  3. Optimum Concentrations of Trichoderma longibrachiatum and Cadusafos for Controlling Meloidogyne javanica on Zucchini Plants

    Science.gov (United States)

    Sokhandani, Zahra; Moosavi, Mohammad Reza; Basirnia, Tahereh

    2016-01-01

    A factorial experiment was established in a completely randomized design to verify the effect of different inoculum levels of an Iranian isolate of Trichoderma longibrachiatum separately and in combination with various concentrations of cadusafos against Meloidogyne javanica in the greenhouse. Zucchini seeds were soaked for 12 hr in five densities (0, 105, 106, 107, and 108 spores/ml suspension) of the fungus prior to planting in pots containing four concentrations of cadusafos (0, 0.5, 1, and 2 mg a.i./kg soil). The data were analyzed using a custom response surface regression model and the response surface curve and contour plots were drawn. Reliability of the model was examined by comparing the result of new experimental treatments with the predicted results. The optimal levels of these two variables also were calculated. The interactive effects of concentrations of Trichoderma and cadusafos were insignificant for several responses such as the total number of eggs per gram soil, the number of intact eggs per gram soil, nematode reproduction factor, and control percent. Closeness of experimental mean values with the expected values proved the validity of the model. The optimal levels of the cadusafos concentration and Trichoderma concentration that caused the best plant growth and lowest nematode reproduction were 1.7 mg a.i./kg soil and 108 conidia/ml suspension, respectively. PMID:27168653

  4. What is the optimum concentration of m-cresol in antivenoms?

    OpenAIRE

    MA Abd-Elsalam; N Abdoon; MS Al-Ahaidib

    2011-01-01

    Antivenoms against snake and scorpion envenomations are usually equine in nature and composed mostly of F(ab')2; additionally, phenol and m-cresol are mainly employed for their preservation. Although there is no study on this subject, m-cresol is utilized by most manufacturers in a concentration that ranges from 0.15 to 0.35 g%. Decreasing the concentration of m-cresol to its minimal effective level may protect victims from its toxic effects and keep the antivenom stable during its shelf life...

  5. Research on Optimum Mass Concentration of Unclassified Tailings Paste based on the Herschel-Bulkley Model

    Directory of Open Access Journals (Sweden)

    Wei Sun

    2013-09-01

    Full Text Available Tailings paste technology is more and more widely applied in underground paste filling, surface paste discharge area. The core of the tailings paste technology is how to prepare qualified paste which has good stability and liquidity. The definitions of qualified paste are divaricated both at home and abroad. Heretofore, there is no uniform definition. In this study, the unclassified tailings of a certain Lead-Zinc mine were configured into slurry at the concentration of 70~78% for the rheological experiment. Based on Herschel-Bulkley model regression, we obtain slurry rheological equation through the flow exponent n to evaluate whether qualified slurry paste. When the flow exponent n = 1, slurry for the Bingham plastic fluid, the qualification concentration of the paste is optimal and the range of 74~76% are the optimal mass concentration. This conclusion is consistent with the reality through a slump experimental validation. This study puts forward with the flow exponent n to determine the optimal quality of paste concentration method is feasible and has great applied value.

  6. Non-Toxic Ionic Liquid Fuels for Exploration Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ORBITEC proposes to develop and test new, non-toxic ionic liquid fuels for propulsion applications. Vintage propulsion systems frequently use highly toxic...

  7. 100-lbf Non-Toxic Storable Liquid Propulsion Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA's Road Maps for both Launch and In Space Propulsion call for the development of non-toxic, monopropellant reaction control systems to replace current...

  8. Functional Genomics of a Non-Toxic Alexandrium Lusitanicum Culture

    Science.gov (United States)

    2007-02-01

    transferred to the dinoflagellate by its ancestral cyanobacteria symbiont and either remained in the reduced chloroplast genome or were transferred to the...Ocean Science 1930 and ngmminering DOCTORAL DISSERTATION Functional Genomics of a Non-Toxic Alexandrium Lusitanicum Culture by Claudia A. Martins...February 2007 DISTRIBUT1 ON, STTEITVENT A App ov,"rj i’or Public Release LU iwbution Unlimited MIT/WHOI 2007-05 Functional Genomics of a Non-Toxic

  9. Rational molecular dynamics scheme for predicting optimum concentration loading of nano-additive in phase change materials

    Directory of Open Access Journals (Sweden)

    Monisha Rastogi

    2015-10-01

    Full Text Available The present study deals with the diffusion and phase transition behaviour of paraffin reinforced with carbon nano-additives namely graphene oxide (GO and surface functionalized single walled carbon nanotubes (SWCNT. Bulk disordered systems of paraffin hydrocarbons impregnated with carbon nano-additives have been generated in realistic equilibrium conformations for potential application as latent heat storage systems. Ab initio molecular dynamics(MD in conjugation with COMPASS forcefield has been implemented using periodic boundary conditions. The proposed scheme allows determination of optimum nano-additive loading for improving thermo-physical properties through analysis of mass, thermal and transport properties; and assists in determination of composite behaviour and related performance from microscopic point of view. It was observed that nanocomposites containing 7.8 % surface functionalised SWCNT and 55% GO loading corresponds to best latent heat storage system. The propounded methodology could serve as a by-pass route for economically taxing and iterative experimental procedures required to attain the optimum composition for best performance. The results also hint at the large unexplored potential of ab-initio classical MD techniques for predicting performance of new nanocomposites for potential phase change material applications.

  10. Rational molecular dynamics scheme for predicting optimum concentration loading of nano-additive in phase change materials

    Science.gov (United States)

    Rastogi, Monisha; Vaish, Rahul; Madhar, Niyaz Ahamad; Shaikh, Hamid; Al-Zahrani, S. M.

    2015-10-01

    The present study deals with the diffusion and phase transition behaviour of paraffin reinforced with carbon nano-additives namely graphene oxide (GO) and surface functionalized single walled carbon nanotubes (SWCNT). Bulk disordered systems of paraffin hydrocarbons impregnated with carbon nano-additives have been generated in realistic equilibrium conformations for potential application as latent heat storage systems. Ab initio molecular dynamics(MD) in conjugation with COMPASS forcefield has been implemented using periodic boundary conditions. The proposed scheme allows determination of optimum nano-additive loading for improving thermo-physical properties through analysis of mass, thermal and transport properties; and assists in determination of composite behaviour and related performance from microscopic point of view. It was observed that nanocomposites containing 7.8 % surface functionalised SWCNT and 55% GO loading corresponds to best latent heat storage system. The propounded methodology could serve as a by-pass route for economically taxing and iterative experimental procedures required to attain the optimum composition for best performance. The results also hint at the large unexplored potential of ab-initio classical MD techniques for predicting performance of new nanocomposites for potential phase change material applications.

  11. OPTIMUM PROSESSENTRERING

    Directory of Open Access Journals (Sweden)

    K. Adendorff

    2012-01-01

    Full Text Available

    ENGLISH ABSTRACT: The paper derives an expression for optimum process centreing for a given design specification and spoilage and/or rework costs.

    AFRIKAANSE OPSOMMING: Die problem Van prosessentrering vir n gegewe ontwerpspesifikasie en herwerk- en/of skrootkoste word behandel.

  12. {sup 131}I treatment of nodular non-toxic goitre

    Energy Technology Data Exchange (ETDEWEB)

    Nygaard, B.; Faber, J.; Hegdeues, L.; Hansen, J.M. [Herlev Hospital (Denmark)

    1996-01-01

    The traditional treatment of a growing nodular non-toxic goitre has for many years been surgical resection or levothyroxine suppressive treatment. During recent years, several studies have reported promising results of {sup 131}I treatment in terms of thyroid size reduction. This review outlines the different treatment modalities on non-toxic nodular goitre with special emphasis on {sup 131}I treatment. By the term nodular goitre the authors include glands with solitary or multiple thyroid nodules with uptake on a scintiscan. At what point of the natural history of non-toxic multinodular goitre {sup 131}I therapy should be used is not clear. In principle, the best result is obtained in smaller goitres and it is possible that the best effect of {sup 131}I is seen if treatment is given to patients with diffuse goitre before these become nodular. However, then there is a potential risk to swing in the direction to where {sup 131}I is used in an indiscriminate way, since the prevalence of non-toxic multinodular goitre is much higher than that of hyperthyroidism. Although we have data on the long-term hazards of {sup 131}I treatment in hyperthyroidism in terms of risk of cancer, we have only follow-up periods of 5 to 10 years for non-toxic goitres in small groups of patients and no data regarding the long-term risk of high-dose {sup 131}I treatment (>600 MBq) for this condition. Ideally, long term randomized studies comparing the effect, side effect and cost-benefit of surgery as opposed to {sup 131}I treatment should be performed. Awaiting this, it is at present mandatory that each individual patient be given a choice of treatment after proper information. 44 refs.

  13. An optimum city size? The scaling relationship for urban population and fine particulate (PM(2.5)) concentration.

    Science.gov (United States)

    Han, Lijian; Zhou, Weiqi; Pickett, Steward T A; Li, Weifeng; Li, Li

    2016-01-01

    We utilize the distribution of PM2.5 concentration and population in large cities at the global scale to illustrate the relationship between urbanization and urban air quality. We found: 1) The relationship varies greatly among continents and countries. Large cities in North America, Europe, and Latin America have better air quality than those in other continents, while those in China and India have the worst air quality. 2) The relationships between urban population size and PM2.5 concentration in large cities of different continents or countries were different. PM2.5 concentration in large cities in North America, Europe, and Latin America showed little fluctuation or a small increasing trend, but those in Africa and India represent a "U" type relationship and in China represent an inverse "U" type relationship. 3) The potential contribution of population to PM2.5 concentration was higher in the large cities in China and India, but lower in other large cities.

  14. Global and regional mortality from ischaemic heart disease and stroke attributable to higher-than-optimum blood glucose concentration: comparative risk assessment.

    Science.gov (United States)

    Danaei, Goodarz; Lawes, Carlene M M; Vander Hoorn, Stephen; Murray, Christopher J L; Ezzati, Majid

    2006-11-11

    Cardiovascular mortality risk increases continuously with blood glucose, from concentrations well below conventional thresholds used to define diabetes. We aimed to quantify population-level effects of all higher-than-optimum concentrations of blood glucose on mortality from ischaemic heart disease and stroke worldwide. We used population distribution of fasting plasma glucose to measure exposure to higher-than-optimum blood glucose. We collated exposure data in 52 countries from individual-level records in population health surveys, systematic reviews, and data provided by investigators. Relative risks for ischaemic heart disease and stroke mortality were from a meta-analysis of more than 200,000 participants in the Asia-Pacific region, with adjustment for other cardiovascular risk factors. In addition to 959,000 deaths directly assigned to diabetes, 1 490,000 deaths from ischaemic heart disease and 709,000 from stroke were attributable to high blood glucose, accounting for 21% and 13% of all deaths from these conditions. 1.8 million of these 2.2 million cardiovascular deaths (84%) were in low-and-middle-income countries (1,224,000 for ischaemic heart disease, 623,000 for stroke). 792,000 (53%) of deaths from ischaemic heart disease and 345,000 (49%) from stroke that were attributable to high blood glucose were in men. Largest numbers of deaths attributable to this risk factor from ischaemic heart disease were in low-and-middle-income countries of South Asia (548,000) and Europe and Central Asia (313,000), and from stroke in South Asia (215,000) and East Asia and Pacific (190,000). Higher-than-optimum blood glucose is a leading cause of cardiovascular mortality in most world regions. Programmes for cardiovascular risk and diabetes management and control at the population level need to be more closely integrated.

  15. Non-Toxic Orbital Maneuvering System Engine Development

    Science.gov (United States)

    Green, Christopher; Claflin, Scott; Maeding, Chris; Butas, John

    1999-01-01

    Recent results using the Aestus engine operated with LOx/ethanol propellant are presented. An experimental program at Rocketdyne Propulsion and Power is underway to adapt this engine for the Boeing Reusable Space Systems Division non-toxic Orbital Maneuvering System/Reaction control System (OMS/RCS) system. Daimler-Chrysler Aerospace designed the Aestus as an nitrogen tetroxide/monomethyl hydrazine (NTO/MMH) upper-stage engine for the Ariane 5. The non-toxic OMS/RCS system's preliminary design requires a LOx/ethanol (O2/C2H5OH) engine that operates with a mixture ratio of 1.8, a specific impulse of 323 seconds, and fits within the original OMS design envelope. This paper describes current efforts to meet these requirements including, investigating engine performance using LOx/ethanol, developing the en-ine system sizing package, and meeting the vehicle operation parameters. Data from hot-fire testing are also presented and discussed.

  16. Evaluation of Optimum Dietary Threonine Requirement by Plasma Free Threonine and Ammonia Concentrations in Surgically Modified Rainbow Trout, Oncorhynchus mykiss

    OpenAIRE

    Yun, Hyeonho; Park, Gunjun; Ok, Imho; Katya, Kumar; Heung, Silas; Sungchul C. Bai

    2015-01-01

    This study was carried out to evaluate the dietary threonine requirement by measuring the plasma free threonine and ammonia concentrations in rainbow trout, Oncorhynchus mykiss after dorsal aorta cannulation. A total of 70 fish (average initial weight 506±8.2 g) were randomly distributed into each of the 14 net cages (5 fish/cage). After 48 hours (h) of feed deprivation, each group was intubated at 1% body weight with one of the seven L-amino acid based diets containing graded levels of threo...

  17. Physicochemical, bioactive, and sensory properties of persimmon-based ice cream: technique for order preference by similarity to ideal solution to determine optimum concentration.

    Science.gov (United States)

    Karaman, Safa; Toker, Ömer Said; Yüksel, Ferhat; Çam, Mustafa; Kayacier, Ahmed; Dogan, Mahmut

    2014-01-01

    In the present study, persimmon puree was incorporated into the ice cream mix at different concentrations (8, 16, 24, 32, and 40%) and some physicochemical (dry matter, ash, protein, pH, sugar, fat, mineral, color, and viscosity), textural (hardness, stickiness, and work of penetration), bioactive (antiradical activity and total phenolic content), and sensory properties of samples were investigated. The technique for order preference by similarity to ideal solution approach was used for the determination of optimum persimmon puree concentration based on the sensory and bioactive characteristics of final products. Increase in persimmon puree resulted in a decrease in the dry matter, ash, fat, protein contents, and viscosity of ice cream mix. Glucose, fructose, sucrose, and lactose were determined to be major sugars in the ice cream samples including persimmon and increase in persimmon puree concentration increased the fructose and glucose content. Better melting properties and textural characteristics were observed for the samples with the addition of persimmon. Magnesium, K, and Ca were determined to be major minerals in the samples and only K concentration increased with the increase in persimmon content. Bioactive properties of ice cream samples improved and, in general, acetone-water extracts showed higher bioactivity compared with ones obtained using methanol-water extracts. The technique for order preference by similarity to ideal solution approach showed that the most preferred sample was the ice cream containing 24% persimmon puree.

  18. A bona fide two-dimensional percolation model: an insight into the optimum photoactivator concentration in La2/3-xEuxTa2O7 nanosheets

    Directory of Open Access Journals (Sweden)

    Tadashi C Ozawa, Katsutoshi Fukuda, Yasuo Ebina, Kosuke Kosuda, Akira Sato, Yuichi Michiue, Keiji Kurashima and Takayoshi Sasaki

    2011-01-01

    Full Text Available La–Eu solid solution nanosheets La2/3−xEuxTa2O7 have been synthesized, and their photoluminescence properties have been investigated. La2/3−xEuxTa2O7 nanosheets were prepared from layered perovskite compounds Li2La2/3−xEuxTa2O7 as the precursors by soft chemical exfoliation reactions. Both the precursors and the exfoliated nanosheets exhibit a decrease in intralayer lattice parameters as the Eu contents increase. However, there is a discontinuity in this trend between the nominal Eu content ranges x≤ 0.3 and x ≥ 0.4. This discontinuity is attributed to the difference in degree of TaO6 octahedra tilting for the La- and Eu-rich phases. La2/3−xEuxTa2O7 nanosheets exhibit red emission, characteristic of the f–f transitions in Eu3+ photoactivators. The photoluminescence emission can be obtained from both host and direct photoactivator excitation. However, photoluminescence emission through host excitation is much more dominant than that through direct photoactivator excitation, and this behavior is consistent with that of all the other rare-earth photoactivated nanosheets reported previously. The absolute photoluminescence quantum efficiency of the La2/3−xEuxTa2O7 nanosheets increases as the experimentally determined Eu contents increase up to x=0.45 and decrease above it. This result is in good agreement with the optimum photoactivator concentration expected from the percolation theory. These solid solution La2/3−xEuxTa2O7 nanosheets are excellent models for validating the theory of optimum photoactivator concentration in the truly two-dimensional photoactivator matrix.

  19. AMAP, the alleged non-toxic isomer of acetaminophen, is toxic in rat and human liver

    NARCIS (Netherlands)

    Hadi, Mackenzie; Dragovic, Sanja; van Swelm, Rachel; Herpers, Bram; van de Water, Bob; Russel, Frans G. M.; Commandeur, Jan N. M.; Groothuis, Geny M. M.

    2013-01-01

    N-acetyl-meta-aminophenol (AMAP) is generally considered as a non-toxic regioisomer of the well-known hepatotoxicant acetaminophen (APAP). However, so far, AMAP has only been shown to be non-toxic in mice and hamsters. To investigate whether AMAP could also be used as non-toxic analog of APAP in rat

  20. Evaluation of optimum roughage to concentrate ratio in maize stover based complete rations for efficient microbial biomass production using in vitro gas production technique

    Directory of Open Access Journals (Sweden)

    Y. Ramana Reddy

    2016-06-01

    Full Text Available Aim: A study was undertaken to evaluate the optimum roughage to concentrate ratio in maize stover (MS based complete diets for efficient microbial biomass production (EMBP using in vitro gas production technique. Materials and Methods: MS based complete diets with roughage to concentrate ratio of 100:0, 90:10, 80:20, 70:30, 60:40, 50:50, 40:60, and 30:70 were formulated, and 200 mg of oven-dried sample was incubated in water bath at 39°C along with media (rumen liquor [RL] - buffer in in vitro gas syringes to evaluate the gas production. The gas produced was recorded at 8 and 24 h of inc ubation. In vitro organic matter digestibility (IVOMD, metabolizable energy (ME, truly digestible organic matter (TDOM, partitioning factor (PF, and EMBP were calculated using appropriate formulae. Ammonia nitrogen and total volatile fatty acids (TVFAs production were analyzed in RL fluid-media mixture after 24 h of incubation. Results: In vitro gas production (ml at 24 h incubation, IVOMD, ME, TDOM, TVFA concentration, and ammonia nitrogen production were increased (p<0.01 in proportion to the increase in the level of concentrate in the diet. Significantly (p<0.01 higher PF and EMBP was noticed in total mixed ration with roughage to concentrate ratio of 60:40 and 50:50 followed by 70:30 and 40:60. Conclusion: Based on the results, it was concluded that the MS can be included in complete rations for ruminants at the level of 50-60% for better microbial biomass synthesis which in turn influences the performance of growing sheep.

  1. Parathyroid gland function after radioiodine ((131)I) therapy for toxic and non-toxic goitre.

    Science.gov (United States)

    Szumowski, Piotr; Abdelrazek, Saeid; Mojsak, Małgorzata; Rogowski, Franciszek; Kociura-Sawicka, Agnieszka; Myśliwiec, Janusz

    2013-01-01

    The therapeutic effect of radioactive iodine ((131)I) on benign goitre consists of the emission of tissue-destructive beta-radiation. Since the range of beta (131)I radiation in tissue can reach 2.4 mm, it can affect the adjacent parathyroid glands. The purpose of this paper is to assess parathyroid function in patients with toxic and non-toxic goitres, up to five years following (131)I therapy. The study sample consisted of 325 patients with benign goitres (220 with toxic nodular goitre (TNG), 25 with non-toxic nodular goitre (NTNG), and 80 with Graves' disease (GD) treated with (131)I. The therapeutic activity of (131)I for each patient was calculated using Marinelli's formula. The serum levels of fT3, fT4, TSH, iPTH and Ca(2+), Ca and phosphates were determined one week before (131)I administration, as well as every two months up to a year following the therapy, and then after three and five years post-treatment. After two months following the administration of (131)I, all the treated patients showed a statistically significant above normal increase in iPTH concentrations (amounting to a value almost twice the norm in patients with TNG), which remained stable up to ten months after treatment, to return to normal level in the following months. In all the patients, Ca(2+), Ca, phosphates concentration remained within normal range throughout the course of the study. The concentrations of fT3 and fT4 quickly returned to normal after (131)I administration, and remained within normal range until the completion of the study. Radioiodine treatment of benign thyroid disorders results in transient (up to ten months after (131)I administration) hyperparathyroidism. The condition does not influence the level of calcium and phosphates concentration in any significant way.

  2. Assessing health-related quality of life in patients with benign non-toxic goitre

    DEFF Research Database (Denmark)

    Watt, Torquil; Cramon, Per; Frendl, Daniel M

    2014-01-01

    Health-related quality of life (HRQoL) assessments are increasingly used to evaluate treatment effects and to shape the delivery of value based care. Valid generic and disease specific tools are available for quantifying HRQoL in patients with non-toxic goitre. However, few studies have applied...... these validated instruments to assess HRQoL in patients with benign non-toxic goitre. Limited evidence suggests that patients with non-toxic goitre have HRQoL impairments in multiple HRQoL domains. While the HRQoL-impact of non-toxic goitre may be small relative to other severely disabling medical conditions...

  3. Non toxic additives for improved fabric filter performance

    Energy Technology Data Exchange (ETDEWEB)

    Bustard, C.J.; Baldrey, K.E.; Ebner, T.G. [ADA Technologies, Inc., Englewood, CO (United States)] [and others

    1995-11-01

    The overall objective of this three-phase Small Business innovative Research (SBIR) program funded by the Department of Energy pittsburgh Energy Technology Center (PETC) is to commercialize a technology based upon the use of non-toxic, novel flue gas conditioning agents to improve particulate air toxic control and overall fabric filter performance. The ultimate objective of the Phase II program currently in progress is to demonstrate that the candidate additives are successful at full-scale on flue gas from a coal-fired utility boiler. This paper covers bench-scale field tests conducted during the period February through May, 1995. The bench-scale additives testing was conducted on a flue gas slipstream taken upstream of the existing particulate control device at a utility power plant firing a Texas lignite coal. These tests were preceded by extensive testing with additives in the laboratory using a simulated flue gas stream and re-dispersed flyash from the same power plant. The bench-scale field testing was undertaken to demonstrate the performance with actual flue gas of the bet candidate additives previously identified in the laboratory. Results from the bench-scale tests will be used to establish operating parameters for a larger-scale demonstration on either a single baghouse compartment or a full baghouse at the same site.

  4. Improved ultrastructure of marine invertebrates using non-toxic buffers

    Directory of Open Access Journals (Sweden)

    Jacqueline Montanaro

    2016-03-01

    Full Text Available Many marine biology studies depend on field work on ships or remote sampling locations where sophisticated sample preservation techniques (e.g., high-pressure freezing are often limited or unavailable. Our aim was to optimize the ultrastructural preservation of marine invertebrates, especially when working in the field. To achieve chemically-fixed material of the highest quality, we compared the resulting ultrastructure of gill tissue of the mussel Mytilus edulis when fixed with differently buffered EM fixatives for marine specimens (seawater, cacodylate and phosphate buffer and a new fixative formulation with the non-toxic PHEM buffer (PIPES, HEPES, EGTA and MgCl2. All buffers were adapted for immersion fixation to form an isotonic fixative in combination with 2.5% glutaraldehyde. We showed that PHEM buffer based fixatives resulted in equal or better ultrastructure preservation when directly compared to routine standard fixatives. These results were also reproducible when extending the PHEM buffered fixative to the fixation of additional different marine invertebrate species, which also displayed excellent ultrastructural detail. We highly recommend the usage of PHEM-buffered fixation for the fixation of marine invertebrates.

  5. Microcystin uptake and biochemical responses in the freshwater clam Corbicula leana P. exposed to toxic and non-toxic Microcystis aeruginosa: Evidence of tolerance to cyanotoxins

    Directory of Open Access Journals (Sweden)

    Thanh-Luu Pham

    2015-01-01

    Full Text Available We investigated the accumulation and adverse effects of toxic and non-toxic Microcystis in the edible clam Corbicula leana. Treated clams were exposed to toxic Microcystis at 100 μg of MC (microcystin-LReq L−1 for 10 days. The experimental organism was then placed in toxin-free water and fed on non-toxic Microcystis for the following 10 days for depuration. Filtering rates (FRs by C. leana of toxic and non-toxic Microcystis and of the green alga Chlorella vulgaris as a control were estimated. Adverse effects were evaluated though the activity of catalase (CAT, superoxide dismutase (SOD and glutathione S-transferase (GST. Clam accumulated MCs (up to 12.7 ± 2.5 μg g−1 dry weight (DW of free MC and 4.2 ± 0.6 μg g−1 DW of covalently bound MC. Our results suggest that although both toxic and non-toxic cyanobacteria caused adverse effects by inducing the detoxification and antioxidant defense system, the clam was quite resistant to cyanotoxins. The estimated MC concentration in C. leana was far beyond the World Health Organization's (WHO provisional tolerable daily intake (0.04 μg kg−1 day−1, suggesting that consuming clams harvested during cyanobacterial blooms carries a high health risk.

  6. Yellow phosphorus process to convert toxic chemicals to non-toxic products

    Science.gov (United States)

    Chang, S.G.

    1994-07-26

    The present invention relates to a process for generating reactive species for destroying toxic chemicals. This process first contacts air or oxygen with aqueous emulsions of molten yellow phosphorus. This contact results in rapid production of abundant reactive species such as O, O[sub 3], PO, PO[sub 2], etc. A gaseous or liquid aqueous solution organic or inorganic chemicals is next contacted by these reactive species to reduce the concentration of toxic chemical and result in a non-toxic product. The final oxidation product of yellow phosphorus is phosphoric acid of a quality which can be recovered for commercial use. A process is developed such that the byproduct, phosphoric acid, is obtained without contamination of toxic species in liquids treated. A gas stream containing ozone without contamination of phosphorus containing species is also obtained in a simple and cost-effective manner. This process is demonstrated to be effective for destroying many types of toxic organic, or inorganic, compounds, including polychlorinated biphenyls (PCB), aromatic chlorides, amines, alcohols, acids, nitro aromatics, aliphatic chlorides, polynuclear aromatic compounds (PAH), dyes, pesticides, sulfides, hydroxyamines, ureas, dithionates and the like. 20 figs.

  7. In vitro regeneration from petiole explants of non-toxic Jatropha curcas

    KAUST Repository

    Kumar, Nitish

    2011-01-01

    Jatropha curcas, a multipurpose shrub has acquired significant economic potential as biodiesel plant. The seeds or pressed cake is toxic due to the presence of toxic substances and is not useful as food/fodder despite having the best protein composition. A simple, efficient, and reproducible method for plant regeneration through direct organogenesis from petiole explants of non-toxic J. curcas was developed using Murashige and Skoog (MS) medium supplemented with different concentrations of thidiazuron (TDZ). The best induction of shoot buds (57.61%), and number of shoot buds (4.98) per explant were obtained when in vitro petiole explants were placed horizontally on MS medium supplemented with 2.27 mu M TDZ. The Induced shoot buds were transferred to MS medium containing 10 mu M kinetin (Kn), 4.5 mu M 6-benzyl aminopurine (BA), and 5.5 mu M alpha-naphthaleneacetic acid (NAA) for shoot proliferation and subsequent elongation was achieved on MS medium supplemented with 2.25 mu M BA and 8.5 mu M IAA. The elongated shoots could be rooted on half-strength MS medium with 15 mu M IBA, 11.4 mu M IAA and 5.5 mu M NAA with more than 90% survival rate. (C) 2010 Elsevier B.V. All rights reserved.

  8. Comparison of starch and gelatin hydrogels for non-toxic supercapacitor electrolytes

    Science.gov (United States)

    Railanmaa, Anna; Lehtimäki, Suvi; Lupo, Donald

    2017-06-01

    Starch and gelatin are two of the most abundantly available natural polymers. Their non-toxicity, low cost, and compatibility with aqueous solvents make them ideal for use in ubiquitous, environmentally friendly electronics systems. This work presents the results of conductivity measurements through impedance spectroscopy for gelatin- and starch-based aqueous gel electrolytes. The NaCl-based gels were physically cross-linked. The conductivity values were 84.6 mS/cm at 1.5 mol L-1 and 71.5 mS/cm at 2 mol L-1 for gelatin and starch, respectively. The mechanical properties of gelatin were found preferable to those of starch, although they deteriorated significantly when the salt concentration exceeded 2 mol L-1. The ability of the gels to successfully act as a supercapacitor electrolyte was demonstrated with printed electrodes on plastic substrate. The devices were characterized through cyclic voltammetry measurements. The results imply that these polymer gel electrolytes are very promising for replacing the traditional aqueous liquid electrolytes in supercapacitors in applications where, for example, user and environmental safety is essential.

  9. Development of Earth-Abundant and Non-Toxic Thin-Film Solar Cells

    Science.gov (United States)

    Park, Helen Hejin

    Although solar energy is the most abundant energy resource available, photovoltaic solar cells must consist of sufficiently abundant and environmentally friendly elements, for scalable low-cost production to provide a major amount of the world's energy supply. However, scalability is limited in current thin-film solar cell technologies based on Cu(In,Ga)(S,Se)2 and CdTe due to scarce, expensive, and toxic elements. Thin-film solar cells consisting of earth-abundant and non-toxic materials were made from pulsed chemical vapor deposition (pulsed-CVD) of SnS as the p-type absorber layer and atomic layer deposition (ALD) of Zn(O,S) as the n-type buffer layer. Solar cells with a structure of Mo/SnS/Zn(O,S)/ZnO/ITO were studied by varying the synthesis conditions of the SnS and Zn(O,S) layers. Annealing SnS in hydrogen sulfide increased the mobility by more than one order of magnitude, and improved the power conversion efficiency of the solar cell devices. Solar cell performance can be further optimized by adjusting the stoichiometry of Zn(O,S), and by tuning the electrical properties of Zn(O,S) through various in situ or post-annealing treatments. Zn(O,S) can be post-annealed in oxygen atmosphere or doped with nitrogen, by ammonium hydroxide or ammonia gas, during the ALD growth to reduce the carrier concentration, which can be critical for reducing interface recombination at the p-n junction. High carrier concentration buffer layers can be critical for reducing contact resistance with the ITO layer. Zn(O,S) can also be incorporated with aluminum by trimethylaluminum (TMA) doses to either increase or decrease the carrier concentration based on the stoichiometry of Zn(O,S).

  10. Non-Toxic Buffer Layers in Flexible Cu(In,GaSe2 Photovoltaic Cell Applications with Optimized Absorber Thickness

    Directory of Open Access Journals (Sweden)

    Md. Asaduzzaman

    2017-01-01

    Full Text Available Absorber layer thickness gradient in Cu(In1−xGaxSe2 (CIGS based solar cells and several substitutes for typical cadmium sulfide (CdS buffer layers, such as ZnS, ZnO, ZnS(O,OH, Zn1−xSnxOy (ZTO, ZnSe, and In2S3, have been analyzed by a device emulation program and tool (ADEPT 2.1 to determine optimum efficiency. As a reference type, the CIGS cell with CdS buffer provides a theoretical efficiency of 23.23% when the optimum absorber layer thickness was determined as 1.6 μm. It is also observed that this highly efficient CIGS cell would have an absorber layer thickness between 1 μm and 2 μm whereas the optimum buffer layer thickness would be within the range of 0.04–0.06 μm. Among all the cells with various buffer layers, the best energy conversion efficiency of 24.62% has been achieved for the ZnO buffer layer based cell. The simulation results with ZnS and ZnO based buffer layer materials instead of using CdS indicate that the cell performance would be better than that of the CdS buffer layer based cell. Although the cells with ZnS(O,OH, ZTO, ZnSe, and In2S3 buffer layers provide slightly lower efficiencies than that of the CdS buffer based cell, the use of these materials would not be deleterious for the environment because of their non-carcinogenic and non-toxic nature.

  11. Non-toxic retention of nanoceria in murine eyes

    Science.gov (United States)

    Seal, Sudipta; McGinnis, James F.

    2016-01-01

    Purpose We have shown that cerium oxide nanoparticles (nanoceria), with unique characteristics and catalytic activities, are retained in the retina for more than 1 year after a single intravitreal injection and can be potentially used for the treatment of a variety of eye diseases. The objective of this study is to determine whether the retention of nanoceria in the eye causes inflammation or adverse side effects. Methods Wild-type (C57BL/6J) mice at P30 were intravitreally injected with several concentrations of nanoceria. The health of the photoreceptors was assessed by analyzing the expression of photoreceptor-specific genes, and the retinal structure and function. The effect of nanoceria was investigated by analyzing of the vascular system, the expression of inflammatory cytokines, and cellular infiltration into the eye. Results Our data showed that there were no changes in the retinal structure or function, or cytokine gene expression following a single intravitreal injection of nanoceria. Conclusions Nanoceria, at doses ranging from 17.2 ng to 1720 ng per eye, do not cause any damage to the retinal structure and function by 30 days post injection. No cellular infiltration and no increases in inflammatory responses were found in the eyes. Our data indicate that nanoceria are safe to use for treatment of a variety of eye diseases. PMID:27746672

  12. Optimum potassium chloride concentration to reduce hydration capacity of clay formations; Concentracao otima de cloreto de potassio para reduzir a capacidade de hidratacao das formacoes argilosas

    Energy Technology Data Exchange (ETDEWEB)

    Machado, Jose Carlos Vieira [PETROBRAS, Salvador, BA (Brazil). Centro de Recursos Humanos Norte-Nordeste. Setor de Programas de Perfuracao; Oliveira, Manoel Martins de [PETROBRAS, BA (Brazil). Distrito de Perfuracao. Div. de Tecnicas de Perfuracao

    1988-12-31

    An experimental method for ascertaining the optimal concentration of potassium chloride for reducing the hydration and dispersion capacity of clayey formations sensitive to water-based fluids is described. Under this method, filtering time for disperse systems prepared from clayey formation samples is measured. A discussion is offered on theoretical aspects of hydration, expansion, and dispersion of clayey rocks in response to the variations in stress equilibrium states produced by these phenomena when a hole (well) is opened in the rock. The state of the art of this technological branch is also described. (author) 10 refs., 5 figs., 4 tabs.

  13. Comparison of three protein extraction procedures from toxic and non-toxic dinoflagellates for proteomics analysis.

    Science.gov (United States)

    Jiang, Xi-Wen; Wang, Jing; Chan, Leo Lai; Lam, Paul Kwan Sing; Gu, Ji-Dong

    2015-08-01

    Three methods for extraction and preparation of high-quality proteins from both toxic and non-toxic dinoflagellates for proteomics analysis, including Trizol method, Lysis method and Tris method, were compared with the subsequent protein separation profiles using 2-D differential gel electrophoresis (2-D DIGE), Coomassie Blue and silver staining. These methods showed suitability for proteins with different pIs and molecular weights. Tris method was better for low molecular weight and low pI protein isolation; whereas both Lysis and Trizol method were better for high-molecular weight and high pI protein purification. Trizol method showed good results with Alexandrium species and Gynodinium species, and the background in gel was much clearer than the other two methods. At the same time, only Lysis method caused breaking down of the target proteins. On the other hand, Trizol method obtained higher concentration of ribulose-1,5-bisphosphate carboxylase/oxygenase proteins by Western-blotting, while Tris method was the best for peridinin-chlorophyll-protein complexes protein and T1 protein preparation. DIGE was better than Coomassie Blue and silver staining, except for some limitations, such as the high cost of the dyes, relatively short shelf life and the requirements for extensive and special image capturing equipment. Some proteins related to PSTs synthesis in dinoflagellates are hydrophobic with high molecular weight or binding on membranes and Trizol method performed better than Tris method for these proteins. The Trizol method and 2-D DIGE were effective combination for proteomics investigations of dinoflagellates. This procedure allows reliable and high recovery efficiency of proteins from dinoflagellates for better understanding on their occurrence and toxin-production for physiological and biochemical information.

  14. Assessing health-related quality of life in patients with benign non-toxic goitre.

    Science.gov (United States)

    Watt, Torquil; Cramon, Per; Frendl, Daniel M; Ware, John E

    2014-08-01

    Health-related quality of life (HRQoL) assessments are increasingly used to evaluate treatment effects and to shape the delivery of value based care. Valid generic and disease specific tools are available for quantifying HRQoL in patients with non-toxic goitre. However, few studies have applied these validated instruments to assess HRQoL in patients with benign non-toxic goitre. Limited evidence suggests that patients with non-toxic goitre have HRQoL impairments in multiple HRQoL domains. While the HRQoL-impact of non-toxic goitre may be small relative to other severely disabling medical conditions, treatment is almost exclusively elected for HRQoL indications. Thus better quantification of HRQoL, particularly at better (or more favorable) levels where many patients score, is essential. Web and mobile technologies have eased the ability to deliver surveys to patients. Routine consideration of HRQoL provides the opportunity to monitor the impact of treatment on the outcomes most meaningful for patients and the opportunity to help shape the delivery of value based health care.

  15. Quantification of biofilm biomass by staining: Non-toxic safranin can replace the popular crystal violet.

    Science.gov (United States)

    Ommen, Pernille; Zobek, Natalia; Meyer, Rikke Louise

    2017-10-01

    Crystal violet staining is commonly used for quantification of biofilm formation, although it is highly toxic. Here we test safranin as a non-toxic replacement. Safranin staining provided similar results as crystal violet, but with higher reproducibility. We therefore recommend safranin staining for biofilm biomass quantification. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. From the Lab Bench: Should you plant a non-toxic endophyte tall fescue?

    Science.gov (United States)

    A column was written to discuss planting novel endophyte tall fescue for alleviating fescue toxicosis. Endophyte-free tall fescue cultivars can be grazed as a non-toxic alternative, but it maust be understood that it is the endophyte, through production of alkaloids other than ergot alkaloids, that...

  17. The Art Recipe Book, Volume One: 60 Non-toxic Art Materials from Readily Available Materials.

    Science.gov (United States)

    Janeczko, Donna

    This collection of recipes is intended for art teachers to provide low-cost, non-toxic materials for classroom use. The materials needed are readily available and can be purchased in quantity to help the budget conscious teacher. Recipes included are for modeling materials, edible modeling materials, paints and inks, adhesives, fixatives, and…

  18. Triterpenes of toxic and non-toxic taxa of Lantana camara.

    Science.gov (United States)

    Hart, N K; Lamberton, J A; Sioumis, A A; Suares, H; Seawright, A A

    1976-04-15

    The taxa of Lantana camara toxic to animals contain lantadene A lantadene B, whereas in two non-toxic taxa other triterpenes predominate. Several new triterpenes have been characterized. Contrary to earlier claims, lantadene A and to a lesser extent lantadene B are toxic when administered intraruminally to sheep.

  19. Economic benefits of the use of non-toxic mono-propellants for spacecraft applications

    NARCIS (Netherlands)

    Bombelli, V.; Simon, D.; Marée, T.; Moerel, J.L.

    2003-01-01

    The European Space Agency and other institutions have identified the use of non-toxic (or "green") propellants as a substantial cost saving opportunity in manufacturing and ground operating of spacecrafts. This paper attempts to identify and quantify this potential by replacing, in the near future,

  20. Non-Toxic, Non-Flammable, -80 C Phase Change Materials

    Science.gov (United States)

    Cutbirth, J. Michael

    2013-01-01

    The objective of this effort was to develop a non-toxic, non-flammable, -80 C phase change material (PCM) to be used in NASA's ICEPAC capsules for biological sample preservation in flight to and from Earth orbit. A temperature of about -68 C or lower is a critical temperature for maintaining stable cell, tissue, and cell fragment storage.

  1. Assessment of Cost Impacts of Using Non-Toxic Propulsion in Satellites

    Science.gov (United States)

    Schiebener, P. J.; Gies, O.; Stuhlberger, J.; Schmitz, H.-D.

    2002-01-01

    The growing costs of space missions, the need for increased mission performance, and concerns associated with environmental issues deeply influence propulsion system design and propellant selection criteria. A propellant's performance was defined in the past exclusively in terms of specific impulse and density, but now high-performance, non-toxic, non-sophisticated mono- propellant systems are key drivers, and are considered for development to replace the traditional hydrazine (N2H4) mono-propellant thrusters. The mono-propellants under consideration are propellant formulations, which should be environmentally friendly, should have a high density, equal or better performance and better thermal characteristics than hydrazine. These considerations raised interest specially in the candidates of Hydroxylammonium Nitrate (HAN)-based propellants, Ammoniumdinitramide (ADN)-based propellants, Tri-ethanol (TEAN)-based propellants, Hydrazinium Nitroformate (HNF)-based propellants, Hydrogen Peroxide (H2O2)-based propellants. A near-term objective in consideration of satellite related process optimisation is to significantly reduce on-ground operations costs and at the same time improve mission performance. A far-term objective is to obtain a system presenting a very high performance, illustrated by a high specific impulse. Moving to a "non-toxic" propulsion system seems to be a solution to these two goals. The sought after benefits for non-toxic spacecraft mono-propellant propulsion are under investigation taking into account the four main parameters which are mandatory for customer satisfaction while meeting the price constraints: - Reliability, availability, maintainability and safety, - Manufacturing, assembly, integration and test, - Launch preparation and support, - Ground support equipment. These benefits of non-toxic mono-propellants can be proven by various examples, like an expected reduction of development costs due the non-toxicity of propellants which might allow

  2. Prevalence of macroprolactinaemia in regularly menstruating women with non-toxic goitre or autoimmune thyroid disease

    Directory of Open Access Journals (Sweden)

    Lewandowski Krzysztof C

    2012-12-01

    Full Text Available Abstract Background The so called “big-big” prolactin (Prl, also known as macroprolactin is formed by Prl-immunoglobulin (Prl-IgG complexes and may cause elevation of serum Prl concentrations measured by standard assays, potentially leading to unnecessary investigations and/or treatment. In our study, we have endeavoured to assess the prevalence of macroprolactinaemia in euthyroid, regularly menstruating women with thyroid disease, as well as to assess whether autoimmune thyroid disease may result in an increased prevalence of macroprolactinaemia. Material and methods We measured serum Prl in 182 regularly menstruating women aged 32.7 ± 7.5 years (mean ± SD, range 17–46 years who attended endocrine clinic either for investigation of non-toxic goitre (n = 86, age 33.2 ± 7.8 years or with autoimmune thyroid disease (n = 96, age 32.3 ± 7.2 years. Autoimmune thyroid disease was defined as raised titre of at least one anti-thyroid antibody [anti-thyroid peroxidase (anti-TPO, anti-thyroglobulin (anti-Tg and/or anti-TSH-receptor (anti-TSH-R antibodies]. All women were clinically and biochemically euthyroid, either without or on treatment with L-thyroxine. In those with raised Prl (i.e., above 530 mIU/l we ruled out the presence of macroprolactinaemia by polyethylene glycol (PEG precipitation method. Results There was no significant age difference between women with and without autoimmune thyroid disease (p = 0.84. Raised Prl concentrations were found in 10 women with thyroid disease (5.5%, and of those a significant macroprolactinaemia (i.e., reduction of Prl concentrations of more than 60% after PEG precipitation was found in 9 subjects (4.94%. There were no differences in the prevalence of macroprolactinaemia between women with autoimmune thyroid disease (4 out of 96, and without autoimmune thyroid disease (5 out of 86, p = 0.75. Conclusions Approximately one out of twenty women with regular menses is likely

  3. Structural studies on a non toxic homologue of type II RIPs from bitter gourd: Molecular basis of non toxicity, conformational selection and glycan structure

    Indian Academy of Sciences (India)

    Thyageshwar Chandran; Alok Sharma; M Vijayan

    2015-12-01

    The structures of nine independent crystals of bitter gourd seed lectin (BGSL), a non-toxic homologue of type II RIPS, and its sugar complexes have been determined. The four-chain, two-fold symmetric, protein is made up of two identical two-chain modules, each consisting of a catalytic chain and a lectin chain, connected by a disulphide bridge. The lectin chain is made up of two domains. Each domain carries a carbohydrate binding site in type II RIPS of known structure. BGSL has a sugar binding site only on one domain, thus impairing its interaction at the cell surface. The adenine binding site in the catalytic chain is defective. Thus, defects in sugar binding as well as adenine binding appear to contribute to the non-toxicity of the lectin. The plasticity of the molecule is mainly caused by the presence of two possible well defined conformations of a surface loop in the lectin chain. One of them is chosen in the sugar complexes, in a case of conformational selection, as the chosen conformation facilitates an additional interaction with the sugar, involving an arginyl residue in the loop. The -glycosylation of the lectin involves a plant-specific glycan while that in toxic type H RIPS of known structure involves a glycan which is animal as well as plant specific.

  4. Plant regeneration of non-toxic Jatropha curcas—impacts of plant growth regulators, source and type of explants

    KAUST Repository

    Kumar, Nitish

    2011-01-28

    Jatropha curcas is an oil bearing species with multiple uses and considerable economic potential as a biofuel plant, however, oil and deoiled cake are toxic. A non-toxic variety of J. curcas is reported from Mexico. The present investigation explores the effects of different plant growth regulators (PGRs) viz. 6-benzyl aminopurine (BAP) or thidiazuron (TDZ) individually and in combination with indole-3-butyric acid (IBA), on regeneration from in vitro and field-grown mature leaf explants, in vitro and glasshouse-grown seedlings cotyledonary leaf explants of non-toxic J. curcas. In all the tested parameters maximum regeneration efficiency (81.07%) and the number of shoot buds per explants (20.17) was observed on 9.08 μM TDZ containing Murashige and Skoog’s (MS) medium from in vitro cotyledonary leaf explants. The regenerated shoot buds were transferred to MS medium containing 10 μM kinetin (Kn), 4.5 μM BAP and 5.5 μM α-naphthaleneacetic acid (NAA) for shoot proliferation. The proliferated shoots could be elongated on MS medium supplemented with 2.25 μM BAP and 8.5 μM IAA. Rooting was achieved when the basal cut end of elongated shoots were dipped in half strength MS liquid medium containing different concentrations and combinations of IBA, IAA and NAA for four days followed by transfer to growth regulators free half strength MS medium supplemented 0.25 mg/l activated charcoal. The rooted plants could be established in soil with more than 90% survival rate.

  5. Variation of optimum yttrium doping concentrations of perovskite type proton conductors BaZr1-xYxO3-α(0≤x≤0.3) with temperature

    Institute of Scientific and Technical Information of China (English)

    丁玉石; 厉英; 邓文卓; 黄文龙; 王常珍

    2013-01-01

    A solid state reaction method was used to prepare the perovskite-structured compounds BaZr1-xYxO3-α(x=0, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3). The X-ray diffraction (XRD) pattern indicated that the target perovskite phases were obtained. With increasing Y con-centration the unit cell parameters of BaZr1-xYxO3-αsamples were expanded, and Y doping became more difficult. However, high synthesis temperature is helpful to promote Y doping. The SEM results showed that the samples exhibited poor sinterability with in-creasing Y-doping content. Thermal gravimetric (TG) curves analysis showed the more mass decreasing of BaZr1-xYxO3-α(0≤x≤0.3) samples at high temperature with more Y doping and more proton introducing. The electrochemical impedance spectra (EIS) of specimens showed that conductivities of BaZr1-xYxO3-α(0≤x≤0.3) increased with increasing temperature from 300 to 900 °C in wet air. At 900 °C, the conductivity of BaZr1-xYxO3-α(0≤x≤0.3) first increased with increasing doped amount of Y, and reached the high-est value of 1.07×10-3 S/cm when x was 0.2, then decreased gradually with further increasing Y content. At 600 °C, BaZr0.75Y0.25O3-αdisplayed the highest conductivity, while the conductivity of BaZr0.7Y0.3O3-αwas the highest at 300 °C. The results indicated that there should be an optimum Y doping concentration yielding the highest conductivity at a constant temperature, and the optimum Y doping concentration should increase in the humidity atmosphere as the temperature decreases. So increasing the Y-doping concen-tration is helpful to improve the conductivities of BaZr1-xYxO3-αmaterials at low temperature.

  6. Radioiodine therapy in non-toxic multinodular goitre. The possibility of effect-amplification with recombinant human TSH (rhTSH)

    DEFF Research Database (Denmark)

    Bonnema, Steen J; Nielsen, Viveque E; Hegedüs, Laszlo

    2006-01-01

    There is no consensus regarding the optimum treatment of benign non-toxic goitre. L-thyroxine suppressive therapy is widely used, but there is poor evidence of its efficacy, and it may have serious adverse effects on health. Surgery is first choice in large goitres or if malignancy is suspected....... 131I therapy results in a one-year goitre reduction of around 40% in multinodular goitres, usually with a high degree of patient satisfaction and improvement of the inspiratory capacity. The effect is attenuated with increasing goitre size. The risk of hypothyroidism is 22-58% within 5-8 years...... intrathyroidal isotope distribution. Pre-stimulation with even a small dose of rhTSH seems to allow a reduction of the 131I activity while still achieving a mean goitre reduction of approximately 40% within a year. A significantly lower extrathyroidal radiation is achieved by this approach. With an unchanged 131...

  7. Radioiodine therapy of benign non-toxic goitre. Potential role of recombinant human TSH

    DEFF Research Database (Denmark)

    Fast, S; Bonnema, S J; Hegedüs, L

    2011-01-01

    This review provides an update on recombinant human TSH (rh-TSH) augmented radioiodine (¹³¹I) therapy and outlines its potential role in the treatment of symptomatic benign multinodular non-toxic goitre. In some countries, ¹³¹I has been used for three decades to reduce the size of nodular goitres......-56% amplification of goitre reduction at one-year post radioiodine compared to conventional (without rh-TSH) ¹³¹I therapy. Although patient satisfaction is not improved at one-year, this approach facilitates tracheal decompression and is particularly promising in large goitres. The majority of multinodular non......-toxic goitre patients may not require amplified goitre reduction. But as an alternative strategy, rh-TSH allows up to 80% reduction of the therapeutic ¹³¹I activity while still achieving goitre reduction comparable to that of conventional ¹³¹I therapy and maintaining high patient satisfaction. The dose...

  8. Active prey selection in two pelagic copepods feeding on potentially toxic and non-toxic dinoflagellates

    DEFF Research Database (Denmark)

    Schultz, Mette; Kiørboe, Thomas

    2009-01-01

    Grazing on two red tide dinoflagellates, the potentially toxic Karenia mikimotoi and the non-toxic Gyrodinium instriatum, was examined in two species of marine copepods, Pseudocalanus elongatus and Temora longicornis. Both copepods cleared K. mikimotoi at rates that were a little lower but compar......Grazing on two red tide dinoflagellates, the potentially toxic Karenia mikimotoi and the non-toxic Gyrodinium instriatum, was examined in two species of marine copepods, Pseudocalanus elongatus and Temora longicornis. Both copepods cleared K. mikimotoi at rates that were a little lower...... but comparable to those at which they cleared the slightly larger G. instriatum when the two dinoflagellates were offered separately. However, when feeding on mixtures of the two prey species, the clearance rates on K. mikimotoi were substantially reduced in both copepods while their clearances of G. instiatum...

  9. The Optimum Replacement of Weapon

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiao; ZHANG Jin-chun

    2002-01-01

    The theory of LCC (Life Cycle Cost) is applied in this paper. The relation between the economic life of weapon and the optimum replacement is analyzed. The method to define the optimum replacement time of weapon is discussed.

  10. Molecular-receptor-specific, non-toxic, near-infrared-emitting Au cluster-protein nanoconjugates for targeted cancer imaging

    Energy Technology Data Exchange (ETDEWEB)

    Retnakumari, Archana; Setua, Sonali; Menon, Deepthy; Ravindran, Prasanth; Nair, Shantikumar; Koyakutty, Manzoor [Amrita Centre for Nanoscience and Molecular Medicine, Amrita Institute of Medical Science, Cochin, 682 041 (India); Muhammed, Habeeb; Pradeep, Thalappil, E-mail: manzoor_nanomed@yahoo.com [Indian Institute of Technology, DST unit on Nanoscience, Chennai, 600 036 (India)

    2010-02-05

    Molecular-receptor-targeted imaging of folate receptor positive oral carcinoma cells using folic-acid-conjugated fluorescent Au{sub 25} nanoclusters (Au NCs) is reported. Highly fluorescent Au{sub 25} clusters were synthesized by controlled reduction of Au{sup +} ions, stabilized in bovine serum albumin (BSA), using a green-chemical reducing agent, ascorbic acid (vitamin-C). For targeted-imaging-based detection of cancer cells, the clusters were conjugated with folic acid (FA) through amide linkage with the BSA shell. The bioconjugated clusters show excellent stability over a wide range of pH from 4 to 14 and fluorescence efficiency of {approx}5.7% at pH 7.4 in phosphate buffer saline (PBS), indicating effective protection of nanoclusters by serum albumin during the bioconjugation reaction and cell-cluster interaction. The nanoclusters were characterized for their physico-chemical properties, toxicity and cancer targeting efficacy in vitro. X-ray photoelectron spectroscopy (XPS) suggests binding energies correlating to metal Au 4f{sub 7/2{approx}}83.97 eV and Au 4f{sub 5/2{approx}}87.768 eV. Transmission electron microscopy and atomic force microscopy revealed the formation of individual nanoclusters of size {approx}1 nm and protein cluster aggregates of size {approx}8 nm. Photoluminescence studies show bright fluorescence with peak maximum at {approx}674 nm with the spectral profile covering the near-infrared (NIR) region, making it possible to image clusters at the 700-800 nm emission window where the tissue absorption of light is minimum. The cell viability and reactive oxygen toxicity studies indicate the non-toxic nature of the Au clusters up to relatively higher concentrations of 500 {mu}g ml{sup -1}. Receptor-targeted cancer detection using Au clusters is demonstrated on FR{sup +ve} oral squamous cell carcinoma (KB) and breast adenocarcinoma cell MCF-7, where the FA-conjugated Au{sub 25} clusters were found internalized in significantly higher concentrations

  11. Molecular-receptor-specific, non-toxic, near-infrared-emitting Au cluster-protein nanoconjugates for targeted cancer imaging

    Science.gov (United States)

    Retnakumari, Archana; Setua, Sonali; Menon, Deepthy; Ravindran, Prasanth; Muhammed, Habeeb; Pradeep, Thalappil; Nair, Shantikumar; Koyakutty, Manzoor

    2010-02-01

    Molecular-receptor-targeted imaging of folate receptor positive oral carcinoma cells using folic-acid-conjugated fluorescent Au25 nanoclusters (Au NCs) is reported. Highly fluorescent Au25 clusters were synthesized by controlled reduction of Au+ ions, stabilized in bovine serum albumin (BSA), using a green-chemical reducing agent, ascorbic acid (vitamin-C). For targeted-imaging-based detection of cancer cells, the clusters were conjugated with folic acid (FA) through amide linkage with the BSA shell. The bioconjugated clusters show excellent stability over a wide range of pH from 4 to 14 and fluorescence efficiency of ~5.7% at pH 7.4 in phosphate buffer saline (PBS), indicating effective protection of nanoclusters by serum albumin during the bioconjugation reaction and cell-cluster interaction. The nanoclusters were characterized for their physico-chemical properties, toxicity and cancer targeting efficacy in vitro. X-ray photoelectron spectroscopy (XPS) suggests binding energies correlating to metal Au 4f7/2~83.97 eV and Au 4f5/2~87.768 eV. Transmission electron microscopy and atomic force microscopy revealed the formation of individual nanoclusters of size ~1 nm and protein cluster aggregates of size ~8 nm. Photoluminescence studies show bright fluorescence with peak maximum at ~674 nm with the spectral profile covering the near-infrared (NIR) region, making it possible to image clusters at the 700-800 nm emission window where the tissue absorption of light is minimum. The cell viability and reactive oxygen toxicity studies indicate the non-toxic nature of the Au clusters up to relatively higher concentrations of 500 µg ml-1. Receptor-targeted cancer detection using Au clusters is demonstrated on FR+ve oral squamous cell carcinoma (KB) and breast adenocarcinoma cell MCF-7, where the FA-conjugated Au25 clusters were found internalized in significantly higher concentrations compared to the negative control cell lines. This study demonstrates the potential of using

  12. Characterization of ZnS thin films synthesized through a non-toxic precursors chemical bath

    Energy Technology Data Exchange (ETDEWEB)

    Rodríguez, C.A. [Department of Materials Engineering, Faculty of Engineering, University of Concepción, Edmundo Larenas 270, Concepción 4070409 (Chile); Sandoval-Paz, M.G. [Department of Physics, Faculty of Physics and Mathematics, University of Concepción, Concepción (Chile); Cabello, G. [Department of Basic Sciences, Faculty of Sciences, University of Bío-Bío, Campus Fernando May, Chillán (Chile); Flores, M.; Fernández, H. [Department of Physics, Faculty of Physics and Mathematics, University of Chile, Beauchef 850, Santiago (Chile); Carrasco, C., E-mail: ccarrascoc@udec.cl [Department of Materials Engineering, Faculty of Engineering, University of Concepción, Edmundo Larenas 270, Concepción 4070409 (Chile)

    2014-12-15

    Highlights: • High quality ZnS thin films have been deposited by chemical bath deposition technique from a non-toxic precursor’s solution. • Nanocrystalline ZnS thin films with large band gap energy were synthesized without using ammonia. • Evidence that the growing of the thin films is carried out by means of hydroxide mechanism was found. • The properties of these ZnS thin films are similar and in some cases better than the corresponding ones produced using toxic precursors such as ammonia. - Abstract: In solar cells, ZnS window layer deposited by chemical bath technique can reach the highest conversion efficiency; however, precursors used in the process normally are materials highly volatile, toxic and harmful to the environment and health (typically ammonia and hydrazine). In this work the characterization of ZnS thin films deposited by chemical bath in a non-toxic alkaline solution is reported. The effect of deposition technique (growth in several times) on the properties of the ZnS thin film was studied. The films exhibited a high percentage of optical transmission (greater than 80%); as the deposition time increased a decreasing in the band gap values from 3.83 eV to 3.71 eV was observed. From chemical analysis, the presence of ZnS and Zn(OH){sub 2} was identified and X-ray diffraction patterns exhibited a clear peak corresponding to ZnS hexagonal phase (1 0 3) plane, which was confirmed by electron diffraction patterns. From morphological studies, compact samples with well-defined particles, low roughness, homogeneous and pinhole-free in the surface were observed. From obtained results, it is evident that deposits of ZnS–CBD using a non-toxic solution are suitable as window layer for TFSC.

  13. Cysteine as a non toxic corrosion inhibitor for copper alloys in conservation

    DEFF Research Database (Denmark)

    Gravgaard, Mari; van Lanschot, Jettie

    2012-01-01

    The aim of this work is to examine cysteine as an alternative to benzotriazole (BTA) for the conservation of archaeological objects with bronze disease. Investigation of the two inhibitors involved the use of electrochemical techniques, measurements of weight change in high humidity and comparative...... studies of colour changes in the corrosion products. The results obtained in this article demonstrate that cysteine could be a non-toxic alternative to BTA. Cysteine performed as well as BTA on pre-corroded coupons with bronze disease in high humidity and showed acceptable results during testing...

  14. Non-Toxic Orbiter Maneuvering System (OMS) and Reaction Control System

    Science.gov (United States)

    Hurlbert, Eric A.; Nicholson, Leonard S. (Technical Monitor)

    1999-01-01

    NASA is pursuing the technology and advanced development of a non-toxic (NT) orbital maneuvering system (OMS) and reaction control system (RCS) for shuttle upgrades, RLV, and reusable first stages. The primary objectives of the shuttle upgrades program are improved safety, improved reliability, reduced operations time and cost, improved performance or capabilities, and commonality with future space exploration needs. Non-Toxic OMS/RCS offers advantages in each of these categories. A non-toxic OMS/RCS eliminates the ground hazards and the flight safety hazards of the toxic and corrosive propellants. The cost savings for ground operations are over $24M per year for 7 flights, and the savings increase with increasing flight rate up to $44M per year. The OMS/RCS serial processing time is reduced from 65 days to 13 days. The payload capability can be increased up to 5100 Ibms. The non-toxic OMS/RCS also provides improved space station reboost capability up to 20 nautical miles over the current toxic system of 14 nautical miles. A NT OMS/RCS represents a clear advancement in the SOA over MMH/NTO. Liquid oxygen and ethanol are clean burning, high-density propellants that provide a high degree of commonality with other spacecraft subsystems including life support, power, and thermal control, and with future human exploration and development of space missions. The simple and reliable pressure-fed design uses sub-cooled liquid oxygen at 250 to 350 psia, which allows a propellant to remain cryogenic for longer periods of time. The key technologies are thermal insulation and conditioning techniques are used to maintain the sub-cooling. Phase I successfully defined the system architecture, designed an integrated OMS/RCS propellant tank, analyzed the feed system, built and tested the 870 lbf RCS thrusters, and tested the 6000 lbf OMS engine. Phase 11 is currently being planned for the development and test of full-scale prototype of the system in 1999 and 2000

  15. An Optimum Currency Crisis

    Directory of Open Access Journals (Sweden)

    Paolo Pasimeni

    2014-12-01

    Full Text Available This paper presents an ex-post assessment of the current situation of the EMU in light of the conditions prescribed by the theory of Optimum Currency Areas (OCA. The analysis shows that some of those conditions were satisfied at the inception of the EMU, others were missing at the beginning, but improved over time as expected by the endogenous approach to the OCA theory. The common fiscal capacity was the main missing element of the initial construction of the Eurozone, and still is. The common budget is so exiguous that its effectiveness as shock absorption mechanism is negligible. The analysis then shows how some of the concerns raised on the eve of the euro did actually materialize, even if not immediately. First, in its first decade the Eurozone did not experience major turbulences, because growing financial integration was compensating the need for fiscal transfers, channelling the excess of saving from the ‘core’ to the ‘periphery’. Second, the mechanism generated record-high private indebtedness in the ‘periphery’ and exposure of the banks in the ‘core’, making the whole system more fragile as it relied upon financial markets’ stability. Third, once the long-feared shock hit, the mechanism proved weak and non-resilient. The inherent weaknesses of the EMU became evident. Fourth, as it had been foreseen, the cost of the adjustment after the shock fell mainly on labour, with much higher and longer unemployment in the Eurozone than both non-Eurozone EU and the US. Fifth, as the theory suggested, the lack of common mechanisms of adjustment dramatically increased the socio-economic divergences within the EMU. The paper finally presents a simulation for a common budget of the Eurozone, linked to the relative current account positions of the member states.

  16. A high throughput live transparent animal bioassay to identify non-toxic small molecules or genes that regulate vertebrate fat metabolism for obesity drug development

    Directory of Open Access Journals (Sweden)

    Woollett Laura A

    2008-08-01

    142 antagonists may be effective non-toxic anti-obesity therapeutics. Conclusion Owing to the apparently high level of evolutionary conservation of signal transduction pathways regulating lipid metabolism, the zebrafish can be useful for identifying non-toxic small molecules or pharmacological target gene products for developing molecular therapeutics for treating clinical obesity. Our results support the promising potential in applying NAD or resveratrol where the underlying target protein likely involves Sirtuin family member proteins. Furthermore data supports future studies focused on determining whether there is a high concentration window for resveratrol that is effective and non-toxic in high fat obesity murine models.

  17. Enrichment of Cellulosic Waste Hemp (Cannabis sativa Hurd into Non-Toxic Microfibres

    Directory of Open Access Journals (Sweden)

    Reinu E. Abraham

    2016-07-01

    Full Text Available In this study a largely available lignocellulose feedstock hemp (Cannabis sativa, obtained as an industrial waste, was used for cellulose extraction. The extraction of cellulose microfibres from hemp biomass was conducted by alkaline treatment and an acidification process. The extracted cellulose microfibres were characterised using Fourier-transformed infrared spectroscopy (FTIR, Scanning electron microscopy (SEM, thermogravimetric analysis (TGA and X-ray diffraction (XRD. The viability of the study was determined by growing human fibroblasts on the preparation which resulted in being non-toxic; indicating its potential in preparing biological scaffolds. Upon enzymatic hydrolysis of the cellulose microfibre using cellulase from Trichoderma reesei, a maximum of 909 mg/g of reducing sugars were obtained, which endorses its suitability for biofuel production.

  18. Gallium nitride is biocompatible and non-toxic before and after functionalization with peptides.

    Science.gov (United States)

    Jewett, Scott A; Makowski, Matthew S; Andrews, Benjamin; Manfra, Michael J; Ivanisevic, Albena

    2012-02-01

    The toxicity of semiconductor materials can significantly hinder their use for in vitro and in vivo applications. Gallium nitride (GaN) is a material with remarkable properties, including excellent chemical stability. This work demonstrated that functionalized and etched GaN surfaces were stable in aqueous environments and leached a negligible amount of Ga in solution even in the presence of hydrogen peroxide. Also, GaN surfaces in cell culture did not interfere with nearby cell growth, and etched GaN promoted the adhesion of cells compared to etched silicon surfaces. A model peptide, "IKVAV", covalently attached to GaN and silicon surfaces increased the adhesion of PC12 cells. Peptide terminated GaN promoted greater cell spreading and extension of neurites. The results suggest that peptide modified GaN is a biocompatible and non-toxic material that can be used to probe chemical and electrical stimuli associated with neural interfaces.

  19. Challenges for the Development of New Non-Toxic Antifouling Solutions

    Directory of Open Access Journals (Sweden)

    Jean-Philippe Maréchal

    2009-10-01

    Full Text Available Marine biofouling is of major economic concern to all marine industries. The shipping trade is particularly alert to the development of new antifouling (AF strategies, especially green AF paint as international regulations regarding the environmental impact of the compounds actually incorporated into the formulations are becoming more and more strict. It is also recognised that vessels play an extensive role in invasive species propagation as ballast waters transport potentially threatening larvae. It is then crucial to develop new AF solutions combining advances in marine chemistry and topography, in addition to a knowledge of marine biofoulers, with respect to the marine environment. This review presents the recent research progress made in the field of new non-toxic AF solutions (new microtexturing of surfaces, foul-release coatings, and with a special emphasis on marine natural antifoulants as well as the perspectives for future research directions.

  20. Facile development of Au-ring microelectrode for in vivo analysis using non-toxic polydopamine as multifunctional material.

    Science.gov (United States)

    Lin, Yuqing; Wang, Keqing; Xu, Yanan; Li, Linbo; Luo, Jingxuan; Wang, Chao

    2016-04-15

    In this study, we describe a facile and fast wet deposition technique to bottom-up fabricate Au-ring microelectrodes (Au-RMEs) using non-toxic polydopamine as multifunctional grafting material instead of commonly used (3-aminopropyl)-trimethoxysilane (APTMS). The Au-RMEs are fabricated by growing Au film uniformly inside of a pulled glass capillary. Au-RMEs with tip apex diameter ranging from 15 to 50 μm were fabricated involving four consequent steps, i.e. hydroxylating the inside wall of a pulled glass capillaries, grafting adhesive polydopamine (PDA) film to hydroxyl group surface, seeding gold nanoparticles (AuNPs) onto PDA surface and finally growing thickness-tunable gold layer on top of gold nanoparticles. After 3-mercaptopropionic acid (MPA) self-assembled monolayers (SAMs) modification, the Au-RMEs obtain improved specificity and sensitivity for monitoring of dopamine (DA) with respect to alleviating ascorbic acid (AA) interference. The current response is in wide linearity to DA concentration in the range of 0.2-100.0 μM with a correlation coefficient of 0.998 and the detection limit as low as 50.0 nM (S/N=3). In addition, the designed glass substrates of Au-RMEs were mechanically stronger and their tips can be further sharped by adjusting the pulling program. In order to demonstrate the utility of these fabricated microelectrodes in neurochemistry, Au-RMEs were used for electrochemical monitoring of DA release stimulated by K(+) in the striatum of rats. Thus, this study offers a novel and reliable strategy for preparing Au microelectrodes and maybe an attractive alternative to the traditional options for continuous and in vivo electrochemical monitoring of DA in various physiological processes.

  1. Optimum conditions for microbial carbonate precipitation.

    Science.gov (United States)

    Okwadha, George D O; Li, Jin

    2010-11-01

    The type of bacteria, bacterial cell concentration, initial urea concentration, reaction temperature, the initial Ca(2+) concentration, ionic strength, and the pH of the media are some factors that control the activity of the urease enzyme, and may have a significant impact on microbial carbonate precipitation (MCP). Factorial experiments were designed based on these factors to determine the optimum conditions that take into consideration economic advantage while at the same time giving quality results. Sporosarcina pasteurii strain ATCC 11859 was used at constant temperature (25°C) and ionic strength with varying amounts of urea, Ca(2+), and bacterial cell concentration. The results indicate that the rate of ureolysis (k(urea)) increases with bacterial cell concentration, and the bacterial cell concentration had a greater influence on k(urea) than initial urea concentration. At 25 mM Ca(2+) concentration, increasing bacterial cell concentration from 10(6) to 10(8)cells mL⁻¹ increased the CaCO(3) precipitated and CO(2) sequestrated by over 30%. However, when the Ca(2+) concentration was increased 10-fold to 250 mM Ca(2+), the amount of CaCO(3) precipitated and CO(2) sequestrated increased by over 100% irrespective of initial urea concentration. Consequently, the optimum conditions for MCP under our experimental conditions were 666 mM urea and 250 mM Ca(2+) at 2.3×10⁸ cells mL⁻¹ bacterial cell concentration. However, a greater CaCO(3) deposition is achievable with higher concentrations of urea, Ca(2+), and bacterial cells so long as the respective quantities are within their economic advantage. X-ray Diffraction, Scanning Electron Microscopy and Energy Dispersive X-ray analyzes confirmed that the precipitate formed was CaCO(3) and composed of predominantly calcite crystals with little vaterite crystals.

  2. Stimulation of pneumovirus-specific CD8(+) T-cells using a non-toxic recombinant ricin delivery system

    NARCIS (Netherlands)

    Grimaldi, E.; Claassen, E.A.W.

    2007-01-01

    Internalisation of the plant toxin ricin occurs by retrograde transport which delivers the toxin to the ER where it intersects with the MHC class I system for peptide antigen display. Here, we describe the generation of an inactivated, non-toxic, ricin molecule fused to a peptide which elicits a CD8

  3. Non-toxic dose of liposomal honokiol suppresses metastasis of hepatocellular carcinoma through destabilizing EGFR and inhibiting the downstream pathways

    Science.gov (United States)

    Yang, Hansuo; Hu, Jia; Zhao, Chengjian; Chai, LuLu; Chen, Xiang; Shao, Ximing; Wang, Chunyu; Wu, Wenshuang; Wan, Li; Ye, Haoyu; Qiu, Qiang; Peng, Aihua; Wei, Yuquan; Yang, Li; Chen, Lijuan

    2017-01-01

    At present, there is no specific anti-metastasis drug in HCC treatment. Drugs used for primary HCC tumors and tumor metastasis are very similar, among which cytotoxic drugs are prevalent, such as cisplatin, doxorubicin and 5-FU. The EGFR pathway plays an important role in promoting hepatocellular carcinoma (HCC) metastasis. Hence, development of non-toxic anti-metastasis drugs, such as EGFR or downstream pathways inhibitors, is of great importance. In our present study, we found non-toxic dose of liposomal honokiol (LH) could inhibit the HCC metastasis by destabilizing EGFR and inhibiting the downstream pathways. Non-toxic dose of LH significantly inhibited the motility, migration and lamellipodia formation of HepG2 cells in vitro and decreased extravasation of HepG2 cells in a novel metastasis model of transgenic zebrafish. In two lung metastasis models (HepG2 and B16F10) and a spontaneous metastasis model of HepG2 cells, LH remarkably inhibited pulmonary metastasis and regional lymph nodes metastasis without obvious toxicity. Further study showed that destabilizing EGFR and inhibiting the downstream pathways were the main mechanisms of non-toxic dose of LH on metastasis inhibition. Our results provide the preclinical rationale and the underlying mechanisms of LH to suppress HCC metastasis, implicating LH as a potential therapeutic agent to block HCC metastasis without severe side effects. PMID:27906672

  4. The determination of Q192R polymorphism of paraoxonase 1 by using non-toxic substrate p-nitrophenylacetate

    Directory of Open Access Journals (Sweden)

    M R Mogarekar

    2013-01-01

    Conclusion: The Q192R polymorphism of PON1 by using non-toxic substrate p-nitrophenylacetate showed trimodal distribution of QQ (homozygous, QR (heterozygous, and RR (homozygous phenotype and it is comparable with reference method. This method can be used for PON1 phenotype in different pathological and complex disease conditions.

  5. Non-Toxic, Low-Freezing, Drop-In Replacement Heat Transfer Fluids

    Science.gov (United States)

    Cutbirth, J. Michael

    2012-01-01

    A non-toxic, non-flammable, low-freezing heat transfer fluid is being developed for drop-in replacement within current and future heat transfer loops currently using water or alcohol-based coolants. Numerous water-soluble compounds were down-selected and screened for toxicological, physical, chemical, compatibility, thermodynamic, and heat transfer properties. Two fluids were developed, one with a freezing point near 0 C, and one with a suppressed freezing point. Both fluids contain an additive package to improve material compatibility and microbial resistance. The optimized sub-zero solution had a freezing point of 30 C, and a freezing volume expansion of 10-percent of water. The toxicity of the solutions was experimentally determined as LD(50) greater than 5g/kg. The solutions were found to produce minimal corrosion with materials identified by NASA as potentially existing in secondary cooling loops. Thermal/hydrodynamic performance exceeded that of glycol-based fluids with comparable freezing points for temperatures Tf greater than 20 C. The additive package was demonstrated as a buffering agent to compensate for CO2 absorption, and to prevent microbial growth. The optimized solutions were determined to have physically/chemically stable shelf lives for freeze/thaw cycles and longterm test loop tests.

  6. Comparative gene expression in toxic versus non-toxic strains of the marine dinoflagellate Alexandrium minutum

    Directory of Open Access Journals (Sweden)

    Glöckner Gernot

    2010-04-01

    Full Text Available Abstract Background The dinoflagellate Alexandrium minutum typically produces paralytic shellfish poisoning (PSP toxins, which are known only from cyanobacteria and dinoflagellates. While a PSP toxin gene cluster has recently been characterized in cyanobacteria, the genetic background of PSP toxin production in dinoflagellates remains elusive. Results We constructed and analysed an expressed sequence tag (EST library of A. minutum, which contained 15,703 read sequences yielding a total of 4,320 unique expressed clusters. Of these clusters, 72% combined the forward-and reverse reads of at least one bacterial clone. This sequence resource was then used to construct an oligonucleotide microarray. We analysed the expression of all clusters in three different strains. While the cyanobacterial PSP toxin genes were not found among the A. minutum sequences, 192 genes were differentially expressed between toxic and non-toxic strains. Conclusions Based on this study and on the lack of identified PSP synthesis genes in the two existent Alexandrium tamarense EST libraries, we propose that the PSP toxin genes in dinoflagellates might be more different from their cyanobacterial counterparts than would be expected in the case of a recent gene transfer. As a starting point to identify possible PSP toxin-associated genes in dinoflagellates without relying on a priori sequence information, the sequences only present in mRNA pools of the toxic strain can be seen as putative candidates involved in toxin synthesis and regulation, or acclimation to intracellular PSP toxins.

  7. Interaction among non-toxic phytoplankton, toxic phytoplankton and zooplankton: inferences from field observations.

    Science.gov (United States)

    Roy, Shovonlal; Bhattacharya, Sabyasachi; Das, Partha; Chattopadhyay, Joydev

    2007-02-01

    We explore the mutual dependencies and interactions among different groups of species of the plankton population, based on an analysis of the long-term field observations carried out by our group in the North-West coast of the Bay of Bengal. The plankton community is structured into three groups of species, namely, non-toxic phytoplankton (NTP), toxic phytoplankton (TPP) and zooplankton. To find the pair-wise dependencies among the three groups of plankton, Pearson and partial correlation coefficients are calculated. To explore the simultaneous interaction among all the three groups, a time series analysis is performed. Following an Expectation Maximization (E-M) algorithm, those data points which are missing due to irregularities in sampling are estimated, and with the completed data set a Vector Auto-Regressive (VAR) model is analyzed. The overall analysis demonstrates that toxin-producing phytoplankton play two distinct roles: the inhibition on consumption of toxic substances reduces the abundance of zooplankton, and the toxic materials released by TPP significantly compensate for the competitive disadvantages among phytoplankton species. Our study suggests that the presence of TPP might be a possible cause for the generation of a complex interaction among the large number of phytoplankton and zooplankton species that might be responsible for the prolonged coexistence of the plankton species in a fluctuating biomass.

  8. Photochemically-assisted synthesis of non-toxic and biocompatible gold nanoparticles.

    Science.gov (United States)

    Teixeira, Priscila R; Santos, Mayara S C; Silva, Ana Luísa G; Báo, Sônia N; Azevedo, Ricardo B; Sales, Maria José A; Paterno, Leonardo G

    2016-12-01

    This contribution describes the photochemically-assisted synthesis of aqueous colloidal suspensions of non-toxic and biocompatible spherical gold nanoparticles stabilized by branched polyethylenimine, or else Au-np-PEI. The method consists on 30min of photoexcitation (254nm, 16W) at room temperature of an aqueous diluted solution of chloroauric acid (HAuCl4) containing PEI. While the UV irradiation forms the [Au((3+))Cl4(-)]* excited species that succesively transforms into zero valent Au, PEI controls the nucleation step of nanoparticles formation. Varying the PEI to Au molar ratio permits one to tune the size of nanoparticles between 100nm to 8nm. The obtained colloidal suspensions display an intense plasmonic absorption band at 520-530nm and positive zeta potentials greater than +20mV. The cells viability for in vitro tests performed with human connective tissues and human breast adenocarcinoma (MCF-7) cell lines is over 80% and 90%, respectively, when they are incubated with Au-np-PEI formulations (25μgmL(-1)). The present photochemically-assisted synthesis is advantageous because it is fast and does not require for either hazardous or cytotoxic reductant agents and additional purification procedures.

  9. A novel approach to block HIV-1 coreceptor CXCR4 in non-toxic manner.

    Science.gov (United States)

    Liu, Ye; Zhou, Jieqiong; Pan, Ji-An; Mabiala, Prudence; Guo, Deyin

    2014-10-01

    The chemokine receptor CXCR4 is one of the major coreceptors for human immunodeficiency virus type 1 (HIV-1) and considered as an important therapeutic target. Knockdown of CXCR4 by RNA interference has emerged as a promising strategy for combating HIV-1 infection. However, there is a potential drawback to this strategy as undesired side effects may occur due to the loss of natural function of CXCR4. In this study, we developed a novel approach using a single lentiviral vector to express simultaneously CXCR4 dual-shRNAs and an shRNA-resistant CXCR4 mutant possessing the most possible natural functions of CXCR4 and reduced HIV-1 coreceptor activity. Via this approach we achieved the replacement of endogenous CXCR4 by CXCR4 mutant P191A that could compensate the functional loss of endogenous CXCR4 and significant reduction of HIV-1 replication by 59.2 %. Besides, we demonstrated that construction of recombinant lentiviral vector using 2A peptide-based strategy has significant advantages over using additional promoter-based strategy, including increase of lentivirus titer and avoidance of promoter competition. Therefore, the novel approach to block HIV-1 coreceptor CXCR4 without impairing its normal function provides a new strategy for CXCR4-targeted therapeutics for HIV-1 infection and potential universal applications to knock down a cellular protein in non-toxic manner.

  10. Nanomaterials made of non-toxic metallic sulfides: A systematic review of their potential biomedical applications.

    Science.gov (United States)

    Argueta-Figueroa, Liliana; Martínez-Alvarez, O; Santos-Cruz, J; Garcia-Contreras, R; Acosta-Torres, L S; de la Fuente-Hernández, J; Arenas-Arrocena, M C

    2017-07-01

    Metallic sulfides involve the chemical bonding of one or more sulfur atoms to a metal. Metallic sulfides are cheap, abundant semiconductor materials that can be used for several applications. However, an important and emerging use for non-toxic metallic sulfides in biomedical applications has arisen quickly in the medical field. In this systematic review, the available data from electronic databases were collected according to PRISMA alignments for systematic reviews. This review shows that these metallic sulfides could be promising for biomedical uses and applications. This systematic review is focused primarily on the following compounds: silver sulfide, copper sulfide, and iron sulfide. The aim of this review was to provide a quick reference on synthesis methods, biocompatibility, recent advances and perspectives, with remarks on future improvements. The toxicity of metallic sulfides depends directly on the cytotoxicity of their interactions with cells and tissues. Metallic sulfides have potential biomedical applications due to their antibacterial properties, uses in imaging and diagnostics, therapies such as photothermal therapy and chemotherapy in tumors and cancer cells, drug delivery and the fabrication of biosensors for the sensitive and selective detection of moieties, among others. Although current evidence about metallic sulfide NPs is promising, there are still several issues to be addressed before these NPs can be used in biomedicine. The current review is a brief but significant guide to metallic sulfides and their potential uses in the biomedical field. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Lead exposure in American black ducks after implementation of non-toxic shot

    Science.gov (United States)

    Samuel, M.D.; Bowers, E. Frank

    2000-01-01

    Lead poisoning from the ingestion of spent shotgun pellets has been recognized as an important disease of North American waterfowl since Bellrose's (1959) research >40 years ago. Nation-wide regulations banning the use of lead shot for waterfowl hunting were established in 1991. We compared the prevalence of lead exposure in American black ducks (Anas rubripes) wintering on 2 areas in Tennessee before (1986-88) and after the ban (1997-99) to assess the effect of the ban on lead shot on this species. Prevalence of elevated blood lead in black ducks declined by 44% from before (11.7% prevalence) to after (6.5% prevalence) the implementation of non-toxic shot. The reduction in lead exposure was pronounced in adult black ducks (from 14.3% to 5.3%). However, prevalence in lead exposure remained similar in juvenile black ducks (from 8.2% to 8.3%). Additional evidence from lead ingestion and lead poisoning mortality events also indicates that lead exposure has declined in waterfowl in the Mississippi flyway. We believe that lead ingestion will continue to decline, despite the persistence of lead shot in some wetlands. The impact of reduced lead exposure on waterfowl populations needs to be assessed.

  12. Optimum annular focusing by a phase plate

    CERN Document Server

    Arrizón, Victor; Aguirre-Olivas, Dilia; Mellado-Villaseñor, Gabriel

    2015-01-01

    Conventional light focusing, i. e. concentration of an extended optical field within a small area around a point, is a frequently used process in Optics. An important extension to conventional focusing is the generation of the annular focal field of an optical beam. We discuss a simple optical setup that achieves this kind of focusing employing a phase plate as unique optical component. We first establish the class of beams that being transmitted through the phase plate can be focused into an annular field with topological charge of arbitrary integer order q. Then, for each beam in this class we determine the plate transmittance that generates the focal field with the maximum possible peak intensity. In particular, we discuss and implement experimentally the optimum annular focusing of a Gaussian beam. The attributes of optimum annular focal fields, namely the high peak intensity, intensity gradient and narrow annular section, are advantageous for different applications of such structured fields.

  13. Non-toxic silver iodide (AgI) quantum dots sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Moosakhani, S. [Faculty of Polymer Engineering and Color Technology, Amirkabir University of Technology, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of); Color and Polymer Research Center (CPRC), Amirkabir University of Technology, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of); Sabbagh Alvani, A.A., E-mail: sabbagh_alvani@aut.ac.ir [Color and Polymer Research Center (CPRC), Amirkabir University of Technology, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of); Sarabi, A.A. [Faculty of Polymer Engineering and Color Technology, Amirkabir University of Technology, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of); Sameie, H.; Salimi, R.; Kiani, S.; Ebrahimi, Y. [Faculty of Polymer Engineering and Color Technology, Amirkabir University of Technology, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of); Color and Polymer Research Center (CPRC), Amirkabir University of Technology, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of)

    2014-12-15

    Highlights: • We have demonstrated AgI sensitized solar cell for the first time. • Obtained mesoporous titania powders possessed small crystallite size, high purity and surface area, and developed mesopores with a narrow pore size distribution. • Photovoltaic measurements revealed the electron injection from AgI to TiO{sub 2}. • The assembled AgI-QD solar cells yielded a power conversion efficiency of 0.64% under one sun illumination. • AgI may be a suitable candidate material for use as a non-toxic sensitizer in QDSSC. - Abstract: The present study reports the performance of a new photosensitizer -AgI quantum dots (QDs)- and mesoporous titania (TiO{sub 2}) nanocrystals synthesized by sol–gel (SG) method for solar cells. Furthermore, the effects of n-heptane on the textural properties of TiO{sub 2} nanocrystals were comprehensively investigated by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), N{sub 2} adsorption–desorption measurements, and UV–vis spectroscopy. TiO{sub 2} powders exhibited an anatase-type mesoporous structure with a high surface area of 89.7 m{sup 2}/g. Afterwards, the QDs were grown on mesoporous TiO{sub 2} surface to fabricate a TiO{sub 2}/AgI electrode by a successive ionic layer adsorption and reaction (SILAR) deposition route. Current–voltage characteristics and electrochemical impedance spectroscopy (EIS) data demonstrated that the injection of photoexcited electrons from AgI QDs into the TiO{sub 2} matrix produces photocurrents. The assembled AgI-QD solar cells yielded a power conversion efficiency of 0.64% and a short-circuit current of 2.13 mA/cm{sup 2} under one sun illumination.

  14. Non-Toxic Reaction Control System for the Reusable First Stage Vehicle

    Science.gov (United States)

    Keith, E. L.; Rothschild, W. J.

    1999-01-01

    This paper presents the Boeing Reusable Space Systems vision of a Reaction Control System (RCS) for the Reusable First Stage (RFS) being considered as a replacement for the Solid Rocket Booster for the Space Shuttle. The requirement is to achieve reliable vehicle control during the upper atmospheric portion of the RFS trajectory while enabling more efficient ground operations, unhindered by constraints caused by operating with highly toxic RCS propellants. Boeing's objective for this effort is to develop a safer, more efficient and environmentally friendly RCS design approach that is suitable for the RFS concept of operations, including a low cost, efficient turnaround cycle. The Boeing RCS concept utilizes ethanol and liquid oxygen in place of the highly toxic, suspected carcinogen, ozone-depleting mono-methyl-hydrazine and highly toxic nitrogen tetroxide. The Space Shuttle Upgrade program, under the leadership of the NASA Johnson Space Flight Center, is currently developing liquid oxygen and ethanol (ethyl alcohol) technology for use as non-toxic orbital maneuvering system (OMS) and RCS. The development of this liquid oxygen and ethanol technology for the Space Shuttle offers a significant leverage to select much of the same technology for the RFS program. There are significant design and development issues involved with bringing this liquid oxygen and ethanol technology to a state of maturity suitable for an operational RCS. The risks associated with a new LOX and Ethanol RCS are mitigated by maintaining kerosene and hydrogen peroxide RCS technology as an alternative. These issues, presented within this paper, include managing the oxygen supply and achieving reliable ignition in the short pulse mode of engine operation. Performance, reliability and operations requirements are presented along with a specific RCS design concept to satisfying these requirements. The work reported in this paper was performed under NASA Marshall Space Flight Center Contract Number

  15. The development of non-toxic ionic-crosslinked chitosan-based microspheres as carriers for the controlled release of silk sericin.

    Science.gov (United States)

    Aramwit, Pornanong; Ekasit, Sanong; Yamdech, Rungnapha

    2015-10-01

    Silk sericin is recently shown to possess various biological activities for biomedical applications. While various sericin carriers were developed for drug delivery system, very few researches considered sericin as a bioactive molecule itself. In this study, sericin incorporated in the chitosan-based microspheres was introduced as a bioactive molecule and bioactive carrier at the same time. The chitosan/sericin (CH/SS) microspheres at different composition (80/20, 70/30, 60/40, and 50/50) were successfully fabricated using anhydroustri-polyphosphate (TPP) as a polyanionic crosslinker. The microspheres with an average size of 1-4 μm and narrow size distribution were obtained. From FT-IR spectra, the presence of both chitosan and sericin in the microspheres confirmed the occurrence of ionic interaction that crosslink them within the microspheres. We also found that the CH/SS microspheres prepared at 50/50 could encapsulate sericin at the highest percentage (37.28%) and release sericin in the most sustained behavior, possibly due to the strong ionic interaction of the positively charged chitosan and the negatively charged sericin. On the other hand, the composition of CH/SS had no effect on the degradation rate of microspheres. All microspheres continuously degraded and remained around 20% after 14 days of enzymatic degradation. This explained that the ionic crosslinkings between chitosan and sericin could be demolished by the enzyme and hydrolysis. Furthermore, we have verified that all CH/SS microspheres at any concentrations showed non-toxicity to L929 mouse fibroblast cells. Therefore, we suggested that the non-toxic ionic-crosslinked CH/SS microspheres could be incorporated in wound dressing material to achieve the sustained release of sericin for accelerated wound healing.

  16. Optimum Safety Levels for Breakwaters

    DEFF Research Database (Denmark)

    Burcharth, H. F.; Sørensen, John Dalsgaard

    2005-01-01

    Optimum design safety levels for rock and cube armoured rubble mound breakwaters without superstructure are investigated by numerical simulations on the basis of minimization of the total costs over the service life of the structure, taking into account typical uncertainties related to wave stati...

  17. A low-cost non-toxic post-growth activation step for CdTe solar cells.

    Science.gov (United States)

    Major, J D; Treharne, R E; Phillips, L J; Durose, K

    2014-07-17

    Cadmium telluride, CdTe, is now firmly established as the basis for the market-leading thin-film solar-cell technology. With laboratory efficiencies approaching 20 per cent, the research and development targets for CdTe are to reduce the cost of power generation further to less than half a US dollar per watt (ref. 2) and to minimize the environmental impact. A central part of the manufacturing process involves doping the polycrystalline thin-film CdTe with CdCl2. This acts to form the photovoltaic junction at the CdTe/CdS interface and to passivate the grain boundaries, making it essential in achieving high device efficiencies. However, although such doping has been almost ubiquitous since the development of this processing route over 25 years ago, CdCl2 has two severe disadvantages; it is both expensive (about 30 cents per gram) and a water-soluble source of toxic cadmium ions, presenting a risk to both operators and the environment during manufacture. Here we demonstrate that solar cells prepared using MgCl2, which is non-toxic and costs less than a cent per gram, have efficiencies (around 13%) identical to those of a CdCl2-processed control group. They have similar hole densities in the active layer (9 × 10(14) cm(-3)) and comparable impurity profiles for Cl and O, these elements being important p-type dopants for CdTe thin films. Contrary to expectation, CdCl2-processed and MgCl2-processed solar cells contain similar concentrations of Mg; this is because of Mg out-diffusion from the soda-lime glass substrates and is not disadvantageous to device performance. However, treatment with other low-cost chlorides such as NaCl, KCl and MnCl2 leads to the introduction of electrically active impurities that do compromise device performance. Our results demonstrate that CdCl2 may simply be replaced directly with MgCl2 in the existing fabrication process, thus both minimizing the environmental risk and reducing the cost of CdTe solar-cell production.

  18. Breast cancer stem-like cells are inhibited by a non-toxic aryl hydrocarbon receptor agonist.

    Directory of Open Access Journals (Sweden)

    Gérald J Prud'homme

    Full Text Available BACKGROUND: Cancer stem cells (CSCs have increased resistance to cancer chemotherapy. They can be enriched as drug-surviving CSCs (D-CSCs by growth with chemotherapeutic drugs, and/or by sorting of cells expressing CSC markers such as aldehyde dehydrogenase-1 (ALDH. CSCs form colonies in agar, mammospheres in low-adherence cultures, and tumors following xenotransplantation in Scid mice. We hypothesized that tranilast, a non-toxic orally active drug with anti-cancer activities, would inhibit breast CSCs. METHODOLOGY/FINDINGS: We examined breast cancer cell lines or D-CSCs generated by growth of these cells with mitoxantrone. Tranilast inhibited colony formation, mammosphere formation and stem cell marker expression. Mitoxantrone-selected cells were enriched for CSCs expressing stem cell markers ALDH, c-kit, Oct-4, and ABCG2, and efficient at forming mammospheres. Tranilast markedly inhibited mammosphere formation by D-CSCs and dissociated formed mammospheres, at pharmacologically relevant concentrations. It was effective against D-CSCs of both HER-2+ and triple-negative cell lines. Tranilast was also effective in vivo, since it prevented lung metastasis in mice injected i.v. with triple-negative (MDA-MB-231 mitoxantrone-selected cells. The molecular targets of tranilast in cancer have been unknown, but here we demonstrate it is an aryl hydrocarbon receptor (AHR agonist and this plays a key role. AHR is a transcription factor activated by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD, polycyclic aromatic hydrocarbons and other ligands. Tranilast induced translocation of the AHR to the nucleus and stimulated CYP1A1 expression (a marker of AHR activation. It inhibited binding of the AHR to CDK4, which has been linked to cell-cycle arrest. D-CSCs expressed higher levels of the AHR than other cells. Knockdown of the AHR with siRNA, or blockade with an AHR antagonist, entirely abrogated the anti-proliferative and anti-mammosphere activity of tranilast

  19. Recovery of Pyruvic Acid using Tri-n-butylamine Dissolved in Non-Toxic Diluent (Rice Bran Oil)

    Science.gov (United States)

    Pal, Dharm; Keshav, Amit

    2016-04-01

    An attempt has been made to investigate the effectiveness of the vegetable oil based biocompatible solvent for the separation of pyruvic acid from fermentation broth, by using rice bran oil as natural, non-toxic diluent. Reactive extraction of pyruvic acid (0.1-0.5 k mol/m3) from aqueous solutions has been studied using tri-n-butylamine (TBA; 10-70 %) as an extractant dissolved in non toxic rice bran oil at T = 30 ± 1 °C. Results were presented in terms of distribution coefficient (Kd), extraction efficiency (E %), loading ratio (Z), and complexation constant (\\varphi_{α β }). Extraction equilibrium was interpreted using mass action modeling approach. Based on the extent of loading (Z < 0.5) only (1:1), pyruvic acid: TBA complex was proposed. Equilibrium complexation constant was evaluated to 1.22 m3/k mol. Results obtained are useful in understanding the extraction mechanism.

  20. Stress Analysis and Optimum Design of Hot Extrusion Dies

    Institute of Scientific and Technical Information of China (English)

    帅词俊; 肖刚; 倪正顺

    2004-01-01

    A three-dimensional model of a hot extrusion die was developed by using ANSYS software and its second development language-ANSYS parametric design language.A finite element analysis and optimum design were carried out.The three-dimensional stress diagram shows that the stress concentration is rather severe in the bridge of the hot extrusion die, and that the stress distribution is very uneven.The optimum dimensions are obtained.The results show that the optimum height of the extrusion die is 89.596 mm.The optimum radii of diffluence holes are 65.048 mm and 80.065 mm.The stress concentration is reduced by 27%.

  1. Optimum design of steel structures

    CERN Document Server

    Farkas, József

    2013-01-01

    This book helps designers and manufacturers to select and develop the most suitable and competitive steel structures, which are safe, fit for production and economic. An optimum design system is used to find the best characteristics of structural models, which guarantee the fulfilment of design and fabrication requirements and minimize the cost function. Realistic numerical models are used as main components of industrial steel structures. Chapter 1 containts some experiences with the optimum design of steel structures Chapter 2 treats some newer mathematical optimization methods. Chapter 3 gives formulae for fabrication times and costs. Chapters 4 deals with beams and columns. Summarizes the Eurocode rules for design. Chapter 5 deals with the design of tubular trusses. Chapter 6 gives the design of frame structures and fire-resistant design rules for a frame. In Chapters 7 some minimum cost design problems of stiffened and cellular plates and shells are worked out for cases of different stiffenings and loads...

  2. Optimum thickness of Mossbauer absorber

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    If recoilless fraction fa is available, the optimum absorber thickness dopt can be calculated by maximizing the signal to noise ratio or Q factor. In this work,an approach presented is to get experimental Qexp as a function of the thickness, and then fitting Qexp by its theoretical expression gives fa value. At last the dopt value is deduced from a maximum on the fitted curve. In such a way, thicknesses of six specimens with quadrupole or magnetic hyperfine splitting were optimized.

  3. Radioiodine therapy in non-toxic multinodular goitre. The possibility of effect-amplification with recombinant human TSH (rhTSH)

    Energy Technology Data Exchange (ETDEWEB)

    Bonnema, Steen J.; Nielsen, Viveque E.; Hegedues, Laszlo [Odense Univ. Hospital (Denmark). Dept. of Endocrinology and Metabolism

    2006-12-15

    There is no consensus regarding the optimum treatment of benign non-toxic goitre. L-thyroxine suppressive therapy is widely used, but there is poor evidence of its efficacy, and it may have serious adverse effects on health. Surgery is first choice in large goitres or if malignancy is suspected. {sup 131}I therapy results in a one-year goitre reduction of around 40% in multinodular goitres, usually with a high degree of patient satisfaction and improvement of the inspiratory capacity. The effect is attenuated with increasing goitre size. The risk of hypothyroidism is 22-58% within 5-8 years. A sufficient thyroid {sup 131}I uptake is mandatory for {sup 131}I therapy to be feasible and pre-stimulation with recombinant human TSH (rhTSH) increases this considerably. This leads to an increased absorbed thyroid dose by approx.75%, mainly in those patients with the lowest thyroid {sup 131}I uptake, and a more homogeneous intrathyroidal isotope distribution. Pre-stimulation with even a small dose of rhTSH seems to allow a reduction of the {sup 131}I activity while still achieving a mean goitre reduction of approximately 40% within a year. A significantly lower extrathyroidal radiation is achieved by this approach. With an unchanged {sup 131}I activity, rhTSH pre-stimulation improves the goitre reduction by 30-50%. However, this is at the expense of a higher rate of hypothyroidism, cervical pain and transient thyrotoxicosis. Of particular concern is the observation made in healthy persons, that rhTSH results in a transient average thyroid volume increase of 35%. A similar goitre swelling may cause problems in susceptible patients during rhTSH-augmented {sup 131}I therapy. Thus, this concept still needs a closer evaluation before routine use.

  4. Pirenzepine affects scleral metabolic changes in myopia through a non-toxic mechanism.

    Science.gov (United States)

    Truong, Hue-Trung; Cottriall, Charles L; Gentle, Alex; McBrien, Neville A

    2002-01-01

    incorporation (% difference between treated and contralateral control eyes) were significantly lower in the cartilaginous sclera of pirenzepine-MD animals, compared to saline-MD controls (+35.9 +/- 10.1% vs +121.2 +/- 28.6%, Ppirenzepine treated group, when compared to the appropriate saline control. Relative patterns of sulphate incorporation, between treatment and control groups, were essentially identical at both time points examined, regardless of whether myopia was prevented through pirenzepine injection or periods of unoccluded vision. The present study shows that, at a dose of pirenzepine sufficient to prevent experimentally-induced axial myopia, glycosaminoglycan synthesis in the cartilaginous sclera was significantly reduced for a transient period following the injection. These pirenzepine-induced reductions in glycosaminoglycan synthesis were not caused by direct drug toxicity to scleral cells as these changes were reversible and no significant reduction in DNA content was observed in pirenzepine treated eyes. Similar patterns of scleral glycosaminoglycan synthesis changes were found following the provision of brief periods of unoccluded vision further demonstrating that pirenzepine is effective in myopia prevention via a non-toxic mechanism. Consequently, the prevention of myopia development in chicks, with either pirenzepine or brief periods of unoccluded vision, is associated with the transient modulation of scleral glycosaminoglycan synthesis in the cartilaginous sclera. Copyright 2002 Elsevier Science Ltd.

  5. Low-Cost High-Performance Non-Toxic Self-Pressurizing Storable Liquid Bi-Propellant Pressure-Fed Rocket Engine Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Exquadrum proposes a high-performance liquid bi-propellant rocket engine that uses propellants that are non-toxic, self-pressurizing, and low cost. The proposed...

  6. Technology and Advanced Development for a Non-Toxic Orbital Maneuvering System and Reaction Control System for Orbiter Upgrade

    Science.gov (United States)

    Hayes, W. A.; Ferrante, Fred A.; Engelmann, G. L.; Gibson, V. A.; Phillipsen, P. C.

    1999-01-01

    NASA intends to pursue technology applications to upgrade the Space Shuttle Orbiter OMS and RCS systems with non-toxic propellants. The primary objectives of an upgraded OMS/RCS are improved safety and reliability, reduced operations and maintenance costs while meeting basic OMS/RCS operational and performance requirements. The OMS/RCS has a high degree of direct interaction with the crew and requires subsystem and components that are compatible with integration into the orbiter vehicle with regard to external mold-line, power and thermal control The non-toxic propulsion technology is also applicable to future Human Exploration and Development of Space (HEDS) missions. The HEDS missions have similar requirements for attitude control and lander descent/ascent propulsion and which will emphasize the use of In-Situ Resource for propellants. When used as a regenerative coolant as in the Shuttle Orbiter OMS combustion chamber, non-toxic fuels such as ethanol are limited in their cooling capacity by the bulk temperature rise permitted to prevent film boiling or possible coking. Typical regeneratively cooled chambers are constructed from highly conductive copper, which maximizes heat transfer, or from low conductivity materials like stainless steel that can also exacerbate cooling problems. For an ethanol cooled application the heat transfer into the fluid must be controlled to reduce the fuel coolant bulk temperature rise. An approach to provide this control is the subject of this report. This report is being issued to document work done by Aerojet on NASA contract NAS 8-98042. Specifically, this project investigates of the use of ethanol, a designated non-toxic fuel, as a coolant for the Space Shuttle Orbital Maneuvering System Engine combustion chamber. The project also addresses a cost reducing fabrication technique for construction of such a combustion chamber. The study contained three major sub-tasks: an analytical investigation and trade study which included

  7. GIS-modelling the distribution of Rattus norvegicus in urban areas using non toxic attractive baits

    Directory of Open Access Journals (Sweden)

    Roberto Sacchi

    2008-07-01

    Full Text Available Abstract GIS supplies a useful way for analysing and modelling spatial distribution of brown rats Rattus norvegicus in urban areas, supplying maps that predict the occurrence of rats over larger areas. However, two alternative procedures can be used: landscape-based models, which use habitat variables derived from remote sensing satellites or other thematic maps, and interpolation techniques, which convert point samples of species abundance. The first procedure has been previously applied, while the second has never been used until now. In this study, we valued the effectiveness of the interpolating procedure by modelling the distribution of brown rats in a large urban area of northern Italy. During spring and autumn 2004, we positioned non toxic baits in 119 spots distributed over the whole urbanized area of the city and we generated maps of rat presence/absence for the two seasons. Brown rats were irregularly scattered over the city and concentrated mainly around rivers and ditches, as well in the historic centre, particularly where buildings suffer poor maintenance. Seasonal variation of rat occurrence was also detected. Brown rat occurrence may be reliably predicted by the interpolation procedure, which appeared to be a more efficient approach to rat distribution modelling compared with landscape-based procedures. Riassunto Modelli GIS della distribuzione di Rattus norvegicus in ambiente urbano con utilizzo di esche non tossiche. I programmi GIS rappresentano un utile strumento per analizzare e modellizzare la distribuzione del ratto delle chiaviche Rattus norvegicus nelle aree urbane, fornendo mappe in grado di predire la presenza di questa specie su vaste aree. A questo scopo possono essere impiegate due procedure alternative: i modelli basati sul paesaggio, che utilizzano le caratteristiche ambientali desunte da mappe tematiche o immagini satellitari

  8. Polymerization of Lactic Acid by MAGHNITE-H+ a Non-Toxic Montmorillonite Clay Catalyst

    Science.gov (United States)

    Harrane, A.; Belaouedj, M. A.; Meghabar, R.; Belbachir, M.

    2008-08-01

    The development of synthetic biodegradable polymers, such as poly(lactic acid), is particularly important for constructing medical devices, controlled drug release matrix, including scaffolds and sutures, and has attracted growing interest in the biomedical field. Here, we report a novel approach to preparing poly (D, L-lactic acid) (PDLA) as a biodegradable polymer. We investigated in detail the reaction conditions for the simple direct polycondensation of D, L-lactic acid, including the reaction times, temperatures, and catalyst. The molecular weight of synthesized PDLA is dependent on both the reaction temperature, amount of catalyst and time. The optimum reaction condition to obtain PDLA by direct polycondensation using Maghnite-H+[1,2], a proton exchanged Montmorillonite clay, as catalyst was thus determined to be 120 °C, 5% amount of Maghnite-H+ for 28 h with a molecular weight of 7970. The method for PDLA synthesis established here will facilitate production of PDLA of various molecular weights, which may have a potential utility as biomaterials.

  9. Optimum Condition Selection of Xylitol Candida tropicaiis Conversion Production

    Institute of Scientific and Technical Information of China (English)

    JIA Chan-yuan; YANG Ping-ping

    2011-01-01

    [Objective]The aim was to select the optimum conditions of xylitol Candida tropicalis conversion production.[Method]The effect of cell culture time, conversion time, conversion pH value,conversion initial sugar concentration, speed and inoculation rate were determined respectivaiy.[Result]Optimum fermentation conditions were obtained as follows: cell culture 16 h, conversion time 10 h, conversion pH value 5.5,conversion initial sugar concentration 20 g/L, conversion shaking speed 150 r/min, inoculation rate 10% (volume ratio).The yield of xylitol has increased to 90%.[Conclusion]This study had provided basis for the further study on xylitol.

  10. Aloe vera is non-toxic to cells: A microculture tetrazolium technique colorimetric assay study

    Directory of Open Access Journals (Sweden)

    Devi Gopakumar

    2014-01-01

    Full Text Available Introduction: Aloe vera (Av, a succulent of Liliaceae family is now a widely used medicinal plant. Its′ application covers a wide spectrum of human diseases, including oral mucosa, gastric mucosa and skin. Aloe vera preparations in the form of gel, mouth washes and cream are applied topically for many oral diseases. The applications include oral lichen planus, candidiasis, oral submucous fibrosis, geographic tongue, etc. Aims and Objectives: To evaluate the cytotoxicity of Av on human fibroblasts. Materials and Methods: Aloe vera preparation (70% was applied on the fibroblast cell lineage and the cell viability was evaluated by microculture tetrazolium technique (MTT colorimetric assay. Results: The cell viability at different concentrations was measured. The cells have maintained their viability at different concentrations used in the study. Conclusion: Our study shows the cell viability at different sample concentrations of Av. This could open up wide clinical applications of Av for reactive, inflammatory and potentially malignant oral and other mucocutaneous diseases.

  11. 黄瓜愈伤组织继代培养中激素浓度组合的优化%Optimum Combination of Hormone Concentration during Callus Subculture of Cucumber

    Institute of Scientific and Technical Information of China (English)

    黄玉兰; 殷奎德; 岳才军

    2014-01-01

    为确定黄瓜中愈伤组织继代培养中激素浓度的最佳组合,以黄瓜不同外植体,诱导初代愈伤组织,利用最佳外植体子叶诱导的愈伤组织进行继代培养,采用响应面设计分析方法,进行二次多项式回归拟合,预测数学模型,并进行激素浓度组合寻优。结果表明:模型的决定系数 R2为0.9957;激素浓度的最佳组合为MS+6-BA 1.009 mg/L+IAA 0.5502 mg/L+AgN031.1026 mg/L%To optimize hormone combination of cucumber callus subculture,primary callus were induced by different cucumber explants,then primary callus were sbucultured.The mathematical model was established by central composite design combined with response surface methodology and the concentrations of hormones for callus subculture were opti-mized.Result showed that the determination conefficient R2 of the model was 0.9957.Optimal combination of hormone for callus subculture of cucumber was MS with 6-BA 1.009 mg/L,IAA 0.5502 mg/L and AgN03 1.1026 mg/L.

  12. Optimum Solar Conversion Cell Configurations

    Science.gov (United States)

    Chen, Bin (Inventor)

    2015-01-01

    Methods for maximizing a fraction of light energy absorbed in each of three classes of light concentrators (rectangular parallelepipeds, paraboloids and prisms) by choice of incident angle of radiation and of one or more geometrical or physical parameters (absorber thickness, paraboloid dimensions, location of paraboloid focus, prism angles, concentrator material, cladding, prism angles, etc.). Alternatively, the light energy absorbed plus the light energy that escapes through non-total internal reflection within the light concentrator can be minimized.

  13. Relationship between metabolic syndrome and multinodular non-toxic goiter in an inpatient population from a geographic area with moderate iodine deficiency.

    Science.gov (United States)

    Rendina, D; De Filippo, G; Mossetti, G; Zampa, G; Muscariello, R; Benvenuto, G; Vivona, C L; Ippolito, S; Galante, F; Lombardi, G; Biondi, B; Strazzullo, P

    2012-04-01

    Obesity and insulin resistance predispose individuals to the development of both metabolic syndrome and non-toxic nodular thyroid diseases. The aim of this observational, cross-sectional study is to evaluate the relationship between metabolic syndrome and multinodular nontoxic goiter in an inpatient population from a geographic area with moderate iodine deficiency. We examined 1422 Caucasian euthyroid inpatients. Thyroid volume was determined by ultrasound of the neck. A fine-needle aspiration biopsy was performed to evaluate single thyroid nodules and dominant nodules ≥15 mm in euthyroid multinodular goiter. The diagnosis of metabolic syndrome was made according to the criteria of the American Heart Association/ National Heart, Lung, and Blood Institute. Of the sample, 277 patients had clinical evidence of multinodular nontoxic goiter, 461 met the criteria for the diagnosis of metabolic syndrome, and 132 were found to have both conditions. After adjusting for age, gender, body mass index, nicotinism, parity, alcohol intake, thyroid function, and metabolic syndrome- related pharmacological treatment, metabolic syndrome was found to be an independent risk factor for the occurrence of multinodular non-toxic goiter. The relationship between metabolic syndrome and multi nodular non-toxic goiter was apparent in both men and women. In this study of euthyroid inpatients, we demonstrate that metabolic syndrome is an independent risk factor for the occurrence of multinodular non-toxic goiter in a geographic area with moderate iodine deficiency. We propose that patients meeting the criteria for metabolic syndrome should be screened for the presence of multinodular non-toxic goiter.

  14. Minimally Adhesive, Advanced Non-toxic Coatings of Dendrimeric Catalysts in Sol-Gel Matrices

    Science.gov (United States)

    2015-10-19

    19b. TELEPHONE NUMBER (Include area code) 716-645-4228 Standard Form 298 (Rev. 8/98) Prescribed by ANSI Std. Z39.18 ^Ol5fO«S7o3^ Final...Low molar concentrations of long-chain alkyl trialkoxysilanes in combination with C8/TEOS show foul-release characteristics with removal of juvenile ...with high surface area , high surface roughness, and chemical segregation of functionality. 10) Monoliths of 5 mole-% V2O5 or 0=V(0-/Pr)3 in

  15. Heterologous expressed toxic and non-toxic peptide variants of toxin CssII are capable to produce neutralizing antibodies against the venom of the scorpion Centruroides suffusus suffusus.

    Science.gov (United States)

    Hernández-Salgado, Kenya; Estrada, Georgina; Olvera, Alejandro; Coronas, Fredy I; Possani, Lourival D; Corzo, Gerardo

    2009-08-15

    Two toxic and one non-toxic recombinant peptide variants of the mammalian neurotoxin CssII was cloned into the expression vector pQE30 containing a 6His-tag and a Factor Xa proteolytic cleavage site. The toxic recombinant peptides rCssII, HisrCssII and the non-toxic rCssIIE15R were expressed under induction with isopropyl thiogalactoside (IPTG), isolated using chromatographic techniques and folded correctly in vitro. The three recombinant variants showed similar secondary structures as the native CssII, but only the rCssIIE15R was not toxic to mice at concentrations up to 30microg/20g mouse body weight when injected intraperitoneally. All three recombinant peptides were capable of displacing the native CssII from their receptor sites in rat brain synaptosomes, suggesting that they had similar structural and functional characteristics of the native peptides. The three recombinant variants of CssII and the native one were used as antigens for immunization of New Zealand rabbits. The antibodies present in the rabbit antisera were able to recognize the native CssII. Additionally and more importantly, the sera of the immunized rabbits were able to neutralize both the native toxin CssII and the whole soluble venom of the scorpion Centruroides suffusus suffusus. These results indicate that the recombinant peptides can be used to produce antidotes against the venom of this species of scorpion.

  16. The Optimum Growth Rate for Population Reconsidered

    OpenAIRE

    Jaeger, Klaus; Kuhle, Wolfgang

    2007-01-01

    This article gives exact general conditions for the existence of an interior optimum growth rate for population in the neoclassical two-generations-overlapping model. In an economy where high (low) growth rates of population lead to a growth path which is efficient (inefficient) there always exists an interior optimum growth rate for population. In all other cases there exists no interior optimum. The Serendipity Theorem, however, does in general not hold in an economy with government debt. M...

  17. Synthesis of Non-Toxic Silica Particles Stabilized by Molecular Complex Oleic-Acid/Sodium Oleate

    Directory of Open Access Journals (Sweden)

    Catalin Ilie Spataru

    2016-11-01

    Full Text Available The present work is focused on the preparation of biocompatible silica particles from sodium silicate, stabilized by a vesicular system containing oleic acid (OLA and its alkaline salt (OLANa. Silica nanoparticles were generated by the partial neutralization of oleic acid (OLA, with the sodium cation present in the aqueous solutions of sodium silicate. At the molar ratio OLA/Na+ = 2:1, the molar ratio (OLA/OLANa = 1:1 required to form vesicles, in which the carboxyl and carboxylate groups have equal concentrations, was achieved. In order to obtain hydrophobically modified silica particles, octadecyltriethoxysilane (ODTES was added in a sodium silicate sol–gel mixture at different molar ratios. The interactions between the octadecyl groups from the modified silica and the oleyl chains from the OLA/OLANa stabilizing system were investigated via simultaneous thermogravimetry (TG and differential scanning calorimetry (DSC (TG-DSC analyses.A significant decrease in vaporization enthalpy and an increase in amount of ODTES were observed. Additionally, that the hydrophobic interaction between OLA and ODTES has a strong impact on the hybrids’ final morphology and on their textural characteristics was revealed. The highest hydrodynamic average diameter and the most negative ζ potential were recorded for the hybrid in which the ODTES/sodium silicate molar ratio was 1:5. The obtained mesoporous silica particles, stabilized by the OLA/OLANa vesicular system, may find application as carriers for hydrophobic bioactive molecules.

  18. Non-toxic agarose/gelatin-based microencapsulation system containing gallic acid for antifungal application.

    Science.gov (United States)

    Lam, P-L; Gambari, R; Kok, S H-L; Lam, K-H; Tang, J C-O; Bian, Z-X; Lee, K K-H; Chui, C-H

    2015-02-01

    Aspergillus niger (A. niger) is a common species of Aspergillus molds. Cutaneous aspergillosis usually occurs in skin sites near intravenous injection and approximately 6% of cutaneous aspergillosis cases which do not involve burn or HIV-infected patients are caused by A. niger. Biomaterials and biopharmaceuticals produced from microparticle-based drug delivery systems have received much attention as microencapsulated drugs offer an improvement in therapeutic efficacy due to better human absorption. The frequently used crosslinker, glutaraldehyde, in gelatin-based microencapsulation systems is considered harmful to human beings. In order to tackle the potential risks, agarose has become an alternative polymer to be used with gelatin as wall matrix materials of microcapsules. In the present study, we report the eco-friendly use of an agarose/gelatin-based microencapsulation system to enhance the antifungal activity of gallic acid and reduce its potential cytotoxic effects towards human skin keratinocytes. We used optimal parameter combinations, such as an agarose/gelatin ratio of 1:1, a polymer/oil ratio of 1:60, a surfactant volume of 1% w/w and a stirring speed of 900 rpm. The minimum inhibitory concentration of microencapsulated gallic acid (62.5 µg/ml) was significantly improved when compared with that of the original drug (>750 µg/ml). The anti-A. niger activity of gallic acid -containing microcapsules was much stronger than that of the original drug. Following 48 h of treatment, skin cell survival was approximately 90% with agarose/gelatin microcapsules containing gallic acid, whereas cell viability was only 25-35% with free gallic acid. Our results demonstrate that agarose/gelatin-based microcapsules containing gallic acid may prove to be helpful in the treatment of A. niger-induced skin infections near intravenous injection sites.

  19. Controlled delivery of hollow corn protein nanoparticles via non-toxic crosslinking: in vivo and drug loading study.

    Science.gov (United States)

    Xu, Helan; Shen, Li; Xu, Lan; Yang, Yiqi

    2015-02-01

    In this research, controlled delivery of hollow nanoparticles from zein, the corn storage protein, to different organs of mice was achieved via crosslinking using citric acid, a non-toxic polycarboxylic acid derived from starch. Besides, crosslinking significantly enhanced water stability of nanoparticles while preserving their drug loading efficiency. Protein nanoparticles have been widely investigated as vehicles for delivery of therapeutics. However, protein nanoparticles were not stable in physiological conditions, easily cleared by mononuclear phagocyte system (MPS), and thus mainly accumulated and degraded in spleen and liver, the major MPS organs. Effective delivery to major non-MPS organs, such as kidney, was usually difficult to achieve, as well as long resident time of nanoparticles. In this research, hollow zein nanoparticles were chemically crosslinked with citric acid. Controlled delivery and prolonged accumulation of the nanoparticles in kidney, one major non-MPS organ, were achieved. The nanoparticles showed improved stability in aqueous environment at pH 7.4 without affecting the adsorption of 5-FU, a common anticancer drug. In summary, citric acid crosslinked hollow zein nanoparticles could be potential vehicles for controllable delivery of anticancer therapeutics.

  20. Vaccination with non-toxic mutant toxic shock syndrome toxin-1 induces IL-17-dependent protection against Staphylococcus aureus infection.

    Science.gov (United States)

    Narita, Kouji; Hu, Dong-Liang; Asano, Krisana; Nakane, Akio

    2015-06-01

    Toxic shock syndrome toxin-1 (TSST-1) is one of superantigens produced by Staphylococcus aureus. We have previously demonstrated that vaccination with non-toxic mutant TSST-1 (mTSST-1) develops host protection to lethal S. aureus infection in mice. However, the detailed mechanism underlying this protection is necessary to elucidate because the passive transfer of antibodies against TSST-1 fails to provide complete protection against S. aureus infection. In this study, the results showed that interleukin-17A (IL-17A)-producing cells were increased in the spleen cells of mTSST-1-vaccinated mice. The main source of IL-17A in mTSST-1-vaccinated mice was T-helper 17 (Th17) cells. The protective effect of vaccination was induced when the vaccinated wild type but not IL-17A-deficient mice were challenged with S. aureus. Gene expression of chemokines, CCL2 and CXCL1, and infiltration of neutrophils and macrophages were increased in spleens and livers of vaccinated mice after infection. The IL-17A-dependent immune response was TSST-1 specific because TSST-1-deficient S. aureus failed to induce the response. The present study suggests that mTSST-1 vaccination is able to provide the IL-17A-dependent host defense against S. aureus infection which promotes chemokine-mediated infiltration of phagocytes into the infectious foci.

  1. Amelioration of oxidative stress in bio-membranes and macromolecules by non-toxic dye from Morinda tinctoria (Roxb.) roots.

    Science.gov (United States)

    Bhakta, Dipita; Siva, Ramamoorthy

    2012-06-01

    Plant dyes have been in use for coloring and varied purposes since prehistoric times. A red dye found in the roots of plants belonging to genus Morinda is a well recognized coloring ingredient. The dye fraction obtained from the methanolic extract of the roots of Morinda tinctoria was explored for its role in attenuating damages caused by H(2)O(2)-induced oxidative stress. The antioxidant potential of the dye fraction was assessed through DPPH radical scavenging, deoxyribose degradation and inhibition of lipid peroxidation in mice liver. It was subsequently screened for its efficiency in extenuating damage incurred to biomembrane (using erythrocytes and their ghost membranes) and macromolecules (pBR322 DNA, lipids and proteins) from exposure to hydrogen peroxide. In addition, the non-toxic nature of the dye was supported by the histological evaluation conducted on the tissue sections from the major organs of Swiss Albino mice as well as effect on Hep3B cell line (human hepatic carcinoma). The LC-MS confirms the dye fraction to be morindone. Our study strongly suggests that morindone present in the root extracts of M. tinctoria, in addition to being a colorant, definitely holds promise in the pharmaceutical industry.

  2. Emulsifying Activity and Stability of a Non-Toxic Bioemulsifier Synthesized by Microbacterium sp. MC3B-10

    Directory of Open Access Journals (Sweden)

    Benjamín Otto Ortega-Morales

    2013-09-01

    Full Text Available A previously reported bacterial bioemulsifier, here termed microbactan, was further analyzed to characterize its lipid component, molecular weight, ionic character and toxicity, along with its bioemulsifying potential for hydrophobic substrates at a range of temperatures, salinities and pH values. Analyses showed that microbactan is a high molecular weight (700 kDa, non-ionic molecule. Gas chromatography of the lipid fraction revealed the presence of palmitic, stearic, and oleic acids; thus microbactan may be considered a glycolipoprotein. Microbactan emulsified aromatic hydrocarbons and oils to various extents; the highest emulsification index was recorded against motor oil (96%. The stability of the microbactan-motor oil emulsion model reached its highest level (94% at 50 °C, pH 10 and 3.5% NaCl content. It was not toxic to Artemia salina nauplii. Microbactan is, therefore, a non-toxic and non-ionic bioemulsifier of high molecular weight with affinity for a range of oily substrates. Comparative phylogenetic assessment of the 16S rDNA gene of Microbacterium sp. MC3B-10 with genes derived from other marine Microbacterium species suggested that this genus is well represented in coastal zones. The chemical nature and stability of the bioemulsifier suggest its potential application in bioremediation of marine environments and in cosmetics.

  3. A novel non-toxic combined CTA1-DD and ISCOMS adjuvant vector for effective mucosal immunization against influenza virus.

    Science.gov (United States)

    Eliasson, Dubravka Grdic; Helgeby, Anja; Schön, Karin; Nygren, Caroline; El-Bakkouri, Karim; Fiers, Walter; Saelens, Xavier; Lövgren, Karin Bengtsson; Nyström, Ida; Lycke, Nils Y

    2011-05-23

    Here we demonstrate that by using non-toxic fractions of saponin combined with CTA1-DD we can achieve a safe and above all highly efficacious mucosal adjuvant vector. We optimized the construction, tested the requirements for function and evaluated proof-of-concept in an influenza A virus challenge model. We demonstrated that the CTA1-3M2e-DD/ISCOMS vector provided 100% protection against mortality and greatly reduced morbidity in the mouse model. The immunogenicity of the vector was superior to other vaccine formulations using the ISCOM or CTA1-DD adjuvants alone. The versatility of the vector was best exemplified by the many options to insert, incorporate or admix vaccine antigens with the vector. Furthermore, the CTA1-3M2e-DD/ISCOMS could be kept 1 year at 4°C or as a freeze-dried powder without affecting immunogenicity or adjuvanticity of the vector. Strong serum IgG and mucosal IgA responses were elicited and CD4 T cell responses were greatly enhanced after intranasal administration of the combined vector. Together these findings hold promise for the combined vector as a mucosal vaccine against influenza virus infections including pandemic influenza. The CTA1-DD/ISCOMS technology represents a breakthrough in mucosal vaccine vector design which successfully combines immunomodulation and targeting in a safe and stable particulate formation.

  4. A self-adjustable four-point probing system using polymeric three dimensional coils and non-toxic liquid metal

    Energy Technology Data Exchange (ETDEWEB)

    Oyunbaatar, Nomin-Erdene; Choi, Young Soo; Lee, Dong-Weon, E-mail: mems@jnu.ac.kr [MEMS and Nanotechnology Laboratory, School of Mechanical Engineering, Chonnam National University, Gwangju 500757 (Korea, Republic of)

    2015-12-15

    This paper describes a self-adjustable four-point probe (S4PP) system with a square configuration. The S4PP system consists of 3D polymer coil springs for the independent operation of each tungsten (W) probe, microfluidic channels filled with a nontoxic liquid metal, and a LabView-based control system. The 3D coil springs made by PMMA are fabricated with a 3D printer and are positioned in a small container filled with the non-toxic liquid metal. This unique configuration allows independent self-adjustment of the probe heights for precise measurements of the electrical properties of both flexible and large-step-height microsamples. The feasibility of the fabricated S4PP system is evaluated by measuring the specific resistance of Cr and Au thin films deposited on silicon wafers. The system is then employed to evaluate the electrical properties of a Au thin film deposited onto a flexible and easily breakable silicon diaphragm (spring constant: ∼3.6 × 10{sup −5} N/m). The resistance of the Cr thin films (thickness: 450 nm) with step heights of 60 and 90 μm is also successfully characterized. These experimental results indicate that the proposed S4PP system can be applied to common metals and semiconductors as well as flexible and large-step-height samples.

  5. New, highly potent and non-toxic, chromone inhibitors of the human breast cancer resistance protein ABCG2.

    Science.gov (United States)

    Pires, Amanda do Rocio Andrade; Lecerf-Schmidt, Florine; Guragossian, Nathalie; Pazinato, Jaqueline; Gozzi, Gustavo Jabor; Winter, Evelyn; Valdameri, Glaucio; Veale, Alexander; Boumendjel, Ahcène; Di Pietro, Attilio; Pérès, Basile

    2016-10-21

    Breast cancer resistance protein (BCRP/ABCG2) is one of the major transporters involved in the efflux of anticancer compounds, contributing to multidrug resistance (MDR). Inhibition of ABCG2-mediated transport is then considered a promising strategy for overcoming MDR in tumors. We recently identified a chromone derivative, namely MBL-II-141 as a selective ABCG2 inhibitor, with relevant in vivo activity. Here, we report the pharmacomodulation of MBL-II-141, with the aim of identifying key pharmacophoric elements to design more potent selective and non-toxic inhibitors. Through rational structural modifications of MBL-II-141, using simple and affordable chemistry, we obtained highly active and easily-made inhibitors of ABCG2. Among the investigated compounds, derivative 4a, was found to be 3-fold more potent than MBL-II-141. It was similarly efficient as the reference inhibitor Ko143 but with the advantage of a lower intrinsic cytotoxicity, and therefore constitutes the best ABCG2 inhibitor ever reported displaying a very high therapeutic ratio. Copyright © 2016. Published by Elsevier Masson SAS.

  6. A self-adjustable four-point probing system using polymeric three dimensional coils and non-toxic liquid metal.

    Science.gov (United States)

    Oyunbaatar, Nomin-Erdene; Choi, Young Soo; Choi, Yong Soo; Lee, Dong-Weon

    2015-12-01

    This paper describes a self-adjustable four-point probe (S4PP) system with a square configuration. The S4PP system consists of 3D polymer coil springs for the independent operation of each tungsten (W) probe, microfluidic channels filled with a nontoxic liquid metal, and a LabView-based control system. The 3D coil springs made by PMMA are fabricated with a 3D printer and are positioned in a small container filled with the non-toxic liquid metal. This unique configuration allows independent self-adjustment of the probe heights for precise measurements of the electrical properties of both flexible and large-step-height microsamples. The feasibility of the fabricated S4PP system is evaluated by measuring the specific resistance of Cr and Au thin films deposited on silicon wafers. The system is then employed to evaluate the electrical properties of a Au thin film deposited onto a flexible and easily breakable silicon diaphragm (spring constant: ∼3.6 × 10(-5) N/m). The resistance of the Cr thin films (thickness: 450 nm) with step heights of 60 and 90 μm is also successfully characterized. These experimental results indicate that the proposed S4PP system can be applied to common metals and semiconductors as well as flexible and large-step-height samples.

  7. MAXIMUM INFORMATION AND OPTIMUM ESTIMATING FUNCTION

    Institute of Scientific and Technical Information of China (English)

    林路

    2003-01-01

    In order to construct estimating functions in some parametric models, this paper introducestwo classes of information matrices. Some necessary and sufficient conditions for the informationmatrices achieving their upper bounds are given. For the problem of estimating the median,some optimum estimating functions based on the information matrices are acquired. Undersome regularity conditions, an approach to carrying out the best basis function is introduced. Innonlinear regression models, an optimum estimating function based on the information matricesis obtained. Some examples are given to illustrate the results. Finally, the concept of optimumestimating function and the methods of constructing optimum estimating function are developedin more general statistical models.

  8. NOAA Optimum Interpolation (OI) SST V2

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The optimum interpolation (OI) sea surface temperature (SST) analysis is produced weekly on a one-degree grid. The analysis uses in situ and satellite SST's plus...

  9. On Optimum Safety Levels of Breakwaters

    DEFF Research Database (Denmark)

    Burcharth, Hans F.; Sørensen, John Dalsgaard

    2006-01-01

    to resist geotechnical slip failures. Optimum safety levels formulated for use both in deterministic and probabilistic design procedures are given. Results obtained so far indicate that the optimum safety levels for caisson breakwaters are much higher than for rubble mound breakwaters.......The paper presents results from numerical simulations performed with the objective of identifying optimum design safety levels of conventional rubble mound and caisson breakwaters, corresponding to the lowest costs over the service life of the structures. The work is related to the PIANC Working...... Group 47 on "Selection of type of breakwater structures". The paper summaries results given in Burcharth and Sorensen (2005) related to outer rubble mound breakwaters but focus on optimum safety levels for outer caisson breakwaters on low and high rubble foundations placed on sea beds strong enough...

  10. Optimum Pipe Size Selection for Turbulent Flow

    Directory of Open Access Journals (Sweden)

    Timothy A. AKINTOLA

    2009-07-01

    Full Text Available Pipelines are normally designed to deliver fluid at the required head and flow rate in a cost effective manner. Increase in conduit diameter leads to increase in annual capital costs, and decrease in operating costs. Selection of an optimum conduit diameter for a particular fluid flow will therefore be a vital economic decision. This paper presents a computer aided optimisation technique for determination of optimum pipe diameter for a number of idealized turbulent flow. Relationships were formulated connecting theories of turbulent fluid flow with pipeline costing. These were developed into a computer program, written in Microsoft Visual C++ language, for a high-level precision estimate of the optimum pipe diameter, through the least total cost approach. The validity of the program was ascertained through case studies, representative of fluids with different densities and compressibility. The optimum conduit diameter was found to increase linearly with increase in compressibility.

  11. Effects of diuretics on iodine uptake in non-toxic goitre: comparison with low-iodine diet

    Energy Technology Data Exchange (ETDEWEB)

    Kapucu, L.Ozlem; Azizoglu, Firat [Department of Nuclear Medicine, Gazi University, Ankara (Turkey); Ayvaz, Goksun; Karakoc, Ayhan [Department of Endocrinology, Gazi University, Ankara (Turkey)

    2003-09-01

    Low-iodine diet has been employed to achieve iodine depletion prior to radioiodine (RI) therapy. However, treatment with diuretics may be more effective than low-iodine diet in causing iodine depletion and subsequent increase in RI uptake by the thyroid. Fifty-five patients with non-toxic goitre were given 0.20 MBq RI p.o. on the first day of the study and thyroid uptake was measured. In 15 patients, a low-iodine diet was started and continued for 14 days. The remaining 40 patients received furosemide 40 mg/day orally for 5 days with an unrestricted diet. On the 15th day of the study, all patients were given 0.20 MBq RI p.o. and thyroid RI uptake was measured again. Additionally, 24-h urinary iodine excretion and RI clearance were measured on the 1st and 6th days in 21 patients from the furosemide group and on the 1st and 15th days in eight patients from the diet group. Furosemide administration led to a 58.40% increase in iodine uptake over the baseline value, which was significantly higher than the increase caused by low-iodine diet (17.22%) (P<0.0001). Urinary excretion of RI decreased in both groups similarly (furosemide, 29.45%; low-iodine diet, 21.06%; P=0.33). Iodine clearance also decreased in each group similarly (10.61% vs 7.53%, P=0.53). Treatment with furosemide prior to administration of RI increases the uptake of RI by the thyroid more effectively than does low-iodine diet. (orig.)

  12. Comparative Transcriptome Analysis of a Toxin-Producing Dinoflagellate Alexandrium catenella and Its Non-Toxic Mutant

    Directory of Open Access Journals (Sweden)

    Yong Zhang

    2014-11-01

    Full Text Available The dinoflagellates and cyanobacteria are two major kingdoms of life producing paralytic shellfish toxins (PSTs, a large group of neurotoxic alkaloids causing paralytic shellfish poisonings around the world. In contrast to the well elucidated PST biosynthetic genes in cyanobacteria, little is known about the dinoflagellates. This study compared transcriptome profiles of a toxin-producing dinoflagellate, Alexandrium catenella (ACHK-T, and its non-toxic mutant form (ACHK-NT using RNA-seq. All clean reads were assembled de novo into a total of 113,674 unigenes, and 66,812 unigenes were annotated in the known databases. Out of them, 35 genes were found to express differentially between the two strains. The up-regulated genes in ACHK-NT were involved in photosynthesis, carbon fixation and amino acid metabolism processes, indicating that more carbon and energy were utilized for cell growth. Among the down-regulated genes, expression of a unigene assigned to the long isoform of sxtA, the initiator of toxin biosynthesis in cyanobacteria, was significantly depressed, suggesting that this long transcript of sxtA might be directly involved in toxin biosynthesis and its depression resulted in the loss of the ability to synthesize PSTs in ACHK-NT. In addition, 101 putative homologs of 12 cyanobacterial sxt genes were identified, and the sxtO and sxtZ genes were identified in dinoflagellates for the first time. The findings of this study should shed light on the biosynthesis of PSTs in the dinoflagellates.

  13. Toxic and non-toxic aggregates from the SBMA and normal forms of androgen receptor have distinct oligomeric structures.

    Science.gov (United States)

    Jochum, Tobias; Ritz, Manuela E; Schuster, Christoph; Funderburk, Sarah F; Jehle, Katja; Schmitz, Katja; Brinkmann, Falko; Hirtz, Michael; Moss, David; Cato, Andrew C B

    2012-06-01

    Hormone-dependent aggregation of the androgen receptor (AR) with a polyglutamine (polyQ) stretch amplification (>38) is considered to be the causative agent of the neurodegenerative disorder spinal and bulbar muscular atrophy (SBMA), consistent with related neurodegenerative diseases involving polyQ-extended proteins. In spite of the widespread acceptance of this common causal hypothesis, little attention has been paid to its apparent incompatibility with the observation of AR aggregation in healthy individuals with no polyQ stretch amplification. Here we used atomic force microscopy (AFM) to characterize sub-micrometer scale aggregates of the wild-type (22 glutamines) and the SBMA form (65 glutamines), as well as a polyQ deletion mutant (1 glutamine) and a variant with a normal length polyQ stretch but with a serine to alanine double mutation elsewhere in the protein. We used a baculovirus-insect cell expression system to produce full-length proteins for these structural analyses. We related the AFM findings to cytotoxicity as measured by expression of the receptors in Drosophila motoneurons or in neuronal cells in culture. We found that the pathogenic AR mutants formed oligomeric fibrils up to 300-600nm in length. These were clearly different from annular oligomers 120-180nm in diameter formed by the nonpathogenic receptors. We could also show that melatonin, which is known to ameliorate the pathological phenotype in the fly model, caused polyQ-extended AR to form annular oligomers. Further comparative investigation of these reproducibly distinct toxic and non-toxic oligomers could advance our understanding of the molecular basis of the polyQ pathologies.

  14. Implementation of optimum solar electricity generating system

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Balbir Singh Mahinder, E-mail: balbir@petronas.com.my; Karim, Samsul Ariffin A., E-mail: samsul-ariffin@petronas.com.my [Department of Fundamental and Applied Sciences, Universiti Teknologi PETRONAS, 31750 Bandar Seri Iskandar, Perak (Malaysia); Sivapalan, Subarna, E-mail: subarna-sivapalan@petronas.com.my [Department of Management and Humanities, Universiti Teknologi PETRONAS, 31750 Bandar Seri Iskandar, Perak (Malaysia); Najib, Nurul Syafiqah Mohd; Menon, Pradeep [Department of Electrical and Electronics Engineering, Universiti Teknologi PETRONAS, 31750 Bandar Seri Iskandar, Perak (Malaysia)

    2014-10-24

    Under the 10{sup th} Malaysian Plan, the government is expecting the renewable energy to contribute approximately 5.5% to the total electricity generation by the year 2015, which amounts to 98MW. One of the initiatives to ensure that the target is achievable was to establish the Sustainable Energy Development Authority of Malaysia. SEDA is given the authority to administer and manage the implementation of the feed-in tariff (FiT) mechanism which is mandated under the Renewable Energy Act 2011. The move to establish SEDA is commendable and the FiT seems to be attractive but there is a need to create awareness on the implementation of the solar electricity generating system (SEGS). In Malaysia, harnessing technologies related to solar energy resources have great potential for implementation. However, the main issue that plagues the implementation of SEGS is the intermittent nature of this source of energy. The availability of sunlight is during the day time, and there is a need for electrical energy storage system, so that there is electricity available during the night time as well. The meteorological condition such as clouds, haze and pollution affects the SEGS as well. The PV based SEGS is seems to be promising electricity generating system that can contribute towards achieving the 5.5% target and will be able to minimize the negative effects of utilizing fossil fuels for electricity generation on the environment. Malaysia is committed to Kyoto Protocol, which emphasizes on fighting global warming by achieving stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system. In this paper, the technical aspects of the implementation of optimum SEGS is discussed, especially pertaining to the positioning of the PV panels.

  15. Implementation of optimum solar electricity generating system

    Science.gov (United States)

    Singh, Balbir Singh Mahinder; Sivapalan, Subarna; Najib, Nurul Syafiqah Mohd; Menon, Pradeep; Karim, Samsul Ariffin A.

    2014-10-01

    Under the 10th Malaysian Plan, the government is expecting the renewable energy to contribute approximately 5.5% to the total electricity generation by the year 2015, which amounts to 98MW. One of the initiatives to ensure that the target is achievable was to establish the Sustainable Energy Development Authority of Malaysia. SEDA is given the authority to administer and manage the implementation of the feed-in tariff (FiT) mechanism which is mandated under the Renewable Energy Act 2011. The move to establish SEDA is commendable and the FiT seems to be attractive but there is a need to create awareness on the implementation of the solar electricity generating system (SEGS). In Malaysia, harnessing technologies related to solar energy resources have great potential for implementation. However, the main issue that plagues the implementation of SEGS is the intermittent nature of this source of energy. The availability of sunlight is during the day time, and there is a need for electrical energy storage system, so that there is electricity available during the night time as well. The meteorological condition such as clouds, haze and pollution affects the SEGS as well. The PV based SEGS is seems to be promising electricity generating system that can contribute towards achieving the 5.5% target and will be able to minimize the negative effects of utilizing fossil fuels for electricity generation on the environment. Malaysia is committed to Kyoto Protocol, which emphasizes on fighting global warming by achieving stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system. In this paper, the technical aspects of the implementation of optimum SEGS is discussed, especially pertaining to the positioning of the PV panels.

  16. Non-Toxic Metabolic Management of Metastatic Cancer in VM Mice: Novel Combination of Ketogenic Diet, Ketone Supplementation, and Hyperbaric Oxygen Therapy

    OpenAIRE

    2015-01-01

    The Warburg effect and tumor hypoxia underlie a unique cancer metabolic phenotype characterized by glucose dependency and aerobic fermentation. We previously showed that two non-toxic metabolic therapies - the ketogenic diet with concurrent hyperbaric oxygen (KD+HBOT) and dietary ketone supplementation - could increase survival time in the VM-M3 mouse model of metastatic cancer. We hypothesized that combining these therapies could provide an even greater therapeutic benefit in this model. Mic...

  17. Method for Determining Optimum Injector Inlet Geometry

    Science.gov (United States)

    Trinh, Huu P. (Inventor); Myers, W. Neill (Inventor)

    2015-01-01

    A method for determining the optimum inlet geometry of a liquid rocket engine swirl injector includes obtaining a throttleable level phase value, volume flow rate, chamber pressure, liquid propellant density, inlet injector pressure, desired target spray angle and desired target optimum delta pressure value between an inlet and a chamber for a plurality of engine stages. The method calculates the tangential inlet area for each throttleable stage. The method also uses correlation between the tangential inlet areas and delta pressure values to calculate the spring displacement and variable inlet geometry of a liquid rocket engine swirl injector.

  18. Optimum PN Guidance Law for Maneuvering Target

    Institute of Scientific and Technical Information of China (English)

    SUN Bao-cai; QI Zai-kang

    2007-01-01

    An optimum PN guidance law for maneuvering target is developed using optimal control theory. By estimating the target position and setting the cost function, the guidance law can be deduced even without knowing the missile lateral acceleration. Since the quadratic cost function can make a compromise between the miss distance andthe control constraint, the optimum guidance law obtained is more general. Also, introduced line of sight rate as the input, a practical form of this guidance law is derived. The simulation results show the effectiveness of the guidance laws.

  19. ON OPTIMUM DESIGN OF THE SHEARER DRUM

    Institute of Scientific and Technical Information of China (English)

    TaoChidong; ChenChong

    1996-01-01

    On the basis of the model experiments, a software for optimum design of the shearer drum has been developed, and the main parameters of a shearer drum also have been optimized. The combination of the techniques of optimization with the model experiment makes the designing and theoretical systems of the shearer drum more perfect.

  20. Investigation of optimum wavelengths for oximetry

    Science.gov (United States)

    Huong, Audrey K. C.; Stockford, Ian M.; Crowe, John A.; Morgan, Stephen P.

    2009-07-01

    An evaluation of the optimum choice of wavelengths, when using the 'Modified Lambert-Beer law' to estimate blood oxygen saturation, that minimises the mean error across a range of oxygen saturation values is presented. The stability of this approach and its susceptibility to noise are also considered.

  1. Development of the optimum rotor theories

    DEFF Research Database (Denmark)

    Okulov, Valery; Sørensen, Jens Nørkær; van Kuik, Gijs A.M.

    The purpose of this study is the examination of optimum rotor theories with ideal load distributions along the blades, to analyze some of the underlying ideas and concepts, as well as to illuminate them. The book gives the historical background of the issue and presents the analysis of the proble...

  2. Belichting bromelia: het optimum verschilt per soort

    NARCIS (Netherlands)

    Garcia Victoria, N.; Warmenhoven, M.G.

    2009-01-01

    Het afstemmen van de hoeveelheid assimilatiebelichting en bemesting in de teelt van bromelia's is vakwerk. Extra mest en licht is beter, maar er is een optimum; een plant kan ook te veel mest en licht ontvangen. Voor bepaling van een aangepast teeltrecept is vervolgonderzoek nodig

  3. Common Core: Teaching Optimum Topic Exploration (TOTE)

    Science.gov (United States)

    Karge, Belinda Dunnick; Moore, Roxane Kushner

    2015-01-01

    The Common Core has become a household term and yet many educators do not understand what it means. This article explains the historical perspectives of the Common Core and gives guidance to teachers in application of Teaching Optimum Topic Exploration (TOTE) necessary for full implementation of the Common Core State Standards. An effective…

  4. Minimal Exit Trajectories with Optimum Correctional Manoeuvres

    Directory of Open Access Journals (Sweden)

    T. N. Srivastava

    1980-10-01

    Full Text Available Minimal exit trajectories with optimum correctional manoeuvers to a rocket between two coplaner, noncoaxial elliptic orbits in an inverse square gravitational field have been investigated. Case of trajectories with no correctional manoeuvres has been analysed. In the end minimal exit trajectories through specified orbital terminals are discussed and problem of ref. (2 is derived as a particular case.

  5. Modeling of Solar Concentrators

    Science.gov (United States)

    Rockey, D. E.

    1984-01-01

    Algorithm developed for predicting power output, uniformity of intensity and operating temperature of concentrator-enhanced photovoltaic solar cell arrays. Optimum values for parameters such as reflector geometry found prior to constructing scale models for testing.

  6. Optimum Operational Parameters for Yawed Wind Turbines

    Directory of Open Access Journals (Sweden)

    David A. Peters

    2011-01-01

    Full Text Available A set of systematical optimum operational parameters for wind turbines under various wind directions is derived by using combined momentum-energy and blade-element-energy concepts. The derivations are solved numerically by fixing some parameters at practical values. Then, the interactions between the produced power and the influential factors of it are generated in the figures. It is shown that the maximum power produced is strongly affected by the wind direction, the tip speed, the pitch angle of the rotor, and the drag coefficient, which are specifically indicated by figures. It also turns out that the maximum power can take place at two different optimum tip speeds in some cases. The equations derived herein can also be used in the modeling of tethered wind turbines which can keep aloft and deliver energy.

  7. ROBUST OPTIMUM DESIGN OF LAMINATED COMPOSITE PLATES

    Institute of Scientific and Technical Information of China (English)

    WangXiangyang; ChenJianqiao

    2004-01-01

    A last-ply failure (LPF) analysis method for laminated composite plates is incorporated into the finite element code-ANSYS, and a robust optimum design method is presented. The composite structure is analyzed by considering both in-plane and out-of-plane loads. For a lamina,two major failure modes are considered: matrix failure and fiber breakage that axe characterized by the proper strength criteria in the literature. When a lamina has failed, the laminate stiffness is modified to reflect the damage, and stresses in the structure are re-analyzed. This procedure is repeatedly performed until the whole structure fails and thus the ultimate strength is determined.A structural optimization problem is solved with the fiber orientation and the lamina thickness as the design variables and the LPF load as the objective. Finally, the robust optimum design method for laminates is presented and discussed.

  8. OPTIMUM PLASMA STATES FOR NEXT STEP TOKAMAKS

    Energy Technology Data Exchange (ETDEWEB)

    LIN-LIU,YR; STAMBAUGH,RD

    2002-11-01

    OAK A271 OPTIMUM PLASMA STATES FOR NEXT STEP TOKAMAKS. The dependence of the ideal ballooning {beta} limit on aspect ratio, A, and elongation {kappa} is systematically explored for nearly 100% bootstrap current driven tokamak equilibria in a wide range of the shape parameters (A = 1.2-7.0, {kappa} = 1.5-6.0 with triangularity {delta} = 0.5). The critical {beta}{sub N} is shown to be optimal at {kappa} = 3.0-4.0 for all A studied and increases as A decreases with a dependence close to A{sup -0.5}. The results obtained can be used as a theoretical basis for the choice of optimum aspect ratio and elongation of next step burning plasma tokamaks or tokamak reactors.

  9. Active magnetic bearings for optimum turbomachinery design

    Science.gov (United States)

    Hustak, J.; Kirk, R. G.; Schoeneck, K. A.

    1985-01-01

    The design and shop test results are given for a high speed eight stage centrifugal compressor supported by active magnetic bearings. A brief summary of the rotor dynamics analysis is presented with specific attention given to design considerations for optimum rotor stability. The concerns for retrofit of magnetic bearings in existing machinery are discussed with supporting analysis of a four stage centrifugal compressor. Recommendations are given on design and analysis requirements for successful machinery operation of either retrofit or new design turbomachinery.

  10. Boolean computation of optimum hitting sets

    Energy Technology Data Exchange (ETDEWEB)

    Hulme, B.L.; Baca, L.S.; Shiver, A.W.; Worrell, R.B.

    1984-04-01

    This report presents the results of computational experience in solving weighted hitting set problems by Boolean algebraic methods. The feasible solutions are obtained by Boolean formula manipulations, and the optimum solutions are obtained by comparing the weight sums of the feasible solutions. Both the algebra and the optimization can be accomplished using the SETS language. One application is to physical protection problems. 8 references, 2 tables.

  11. Optimum Arrangement of Taxi Drivers’ Working Hours

    OpenAIRE

    TANIZAKI, Takashi

    2014-01-01

    Part 2: Knowledge Discovery and Sharing; International audience; We propose optimum arrangement of taxi drivers’ working hours. In Japan, income of taxi vehicle is decreasing about 11 thousand yen in the past 15 years. Then some taxi companies are investing to gain more customers. But there are many small taxi companies that are difficult to invest with much money. Therefore we have been researching the other method to gain more customers by little investment for small companies. In this pape...

  12. Optimum design of cast iron finned radiator

    Institute of Scientific and Technical Information of China (English)

    赵立华; 张泓森; 董重成

    2003-01-01

    The height, thickness and spacing of fins have an impact on the thermal characteristics of a radiator.The calculation of heat output and metal thermal intensity for cast iron finned radiator are given by using heat transfer formula of vertical plate and parallel fins. Each factor having effect on the metal thermal intensity of a radiator is analyzed and the optimum structure parameters of a radiator are given in order to maximize metal thermal intensity.

  13. Techniques for evaluating optimum data center operation

    Science.gov (United States)

    Hamann, Hendrik F.; Rodriguez, Sergio Adolfo Bermudez; Wehle, Hans-Dieter

    2017-06-14

    Techniques for modeling a data center are provided. In one aspect, a method for determining data center efficiency is provided. The method includes the following steps. Target parameters for the data center are obtained. Technology pre-requisite parameters for the data center are obtained. An optimum data center efficiency is determined given the target parameters for the data center and the technology pre-requisite parameters for the data center.

  14. Developed Hybrid Model for Propylene Polymerisation at Optimum Reaction Conditions

    Directory of Open Access Journals (Sweden)

    Mohammad Jakir Hossain Khan

    2016-02-01

    Full Text Available A statistical model combined with CFD (computational fluid dynamic method was used to explain the detailed phenomena of the process parameters, and a series of experiments were carried out for propylene polymerisation by varying the feed gas composition, reaction initiation temperature, and system pressure, in a fluidised bed catalytic reactor. The propylene polymerisation rate per pass was considered the response to the analysis. Response surface methodology (RSM, with a full factorial central composite experimental design, was applied to develop the model. In this study, analysis of variance (ANOVA indicated an acceptable value for the coefficient of determination and a suitable estimation of a second-order regression model. For better justification, results were also described through a three-dimensional (3D response surface and a related two-dimensional (2D contour plot. These 3D and 2D response analyses provided significant and easy to understand findings on the effect of all the considered process variables on expected findings. To diagnose the model adequacy, the mathematical relationship between the process variables and the extent of polymer conversion was established through the combination of CFD with statistical tools. All the tests showed that the model is an excellent fit with the experimental validation. The maximum extent of polymer conversion per pass was 5.98% at the set time period and with consistent catalyst and co-catalyst feed rates. The optimum conditions for maximum polymerisation was found at reaction temperature (RT 75 °C, system pressure (SP 25 bar, and 75% monomer concentration (MC. The hydrogen percentage was kept fixed at all times. The coefficient of correlation for reaction temperature, system pressure, and monomer concentration ratio, was found to be 0.932. Thus, the experimental results and model predicted values were a reliable fit at optimum process conditions. Detailed and adaptable CFD results were capable

  15. Graphene oxide selectively targets cancer stem cells, across multiple tumor types: implications for non-toxic cancer treatment, via "differentiation-based nano-therapy".

    Science.gov (United States)

    Fiorillo, Marco; Verre, Andrea F; Iliut, Maria; Peiris-Pagés, Maria; Ozsvari, Bela; Gandara, Ricardo; Cappello, Anna Rita; Sotgia, Federica; Vijayaraghavan, Aravind; Lisanti, Michael P

    2015-02-28

    Tumor-initiating cells (TICs), a.k.a. cancer stem cells (CSCs), are difficult to eradicate with conventional approaches to cancer treatment, such as chemo-therapy and radiation. As a consequence, the survival of residual CSCs is thought to drive the onset of tumor recurrence, distant metastasis, and drug-resistance, which is a significant clinical problem for the effective treatment of cancer. Thus, novel approaches to cancer therapy are needed urgently, to address this clinical need. Towards this end, here we have investigated the therapeutic potential of graphene oxide to target cancer stem cells. Graphene and its derivatives are well-known, relatively inert and potentially non-toxic nano-materials that form stable dispersions in a variety of solvents. Here, we show that graphene oxide (of both big and small flake sizes) can be used to selectively inhibit the proliferative expansion of cancer stem cells, across multiple tumor types. For this purpose, we employed the tumor-sphere assay, which functionally measures the clonal expansion of single cancer stem cells under anchorage-independent conditions. More specifically, we show that graphene oxide effectively inhibits tumor-sphere formation in multiple cell lines, across 6 different cancer types, including breast, ovarian, prostate, lung and pancreatic cancers, as well as glioblastoma (brain). In striking contrast, graphene oxide is non-toxic for "bulk" cancer cells (non-stem) and normal fibroblasts. Mechanistically, we present evidence that GO exerts its striking effects on CSCs by inhibiting several key signal transduction pathways (WNT, Notch and STAT-signaling) and thereby inducing CSC differentiation. Thus, graphene oxide may be an effective non-toxic therapeutic strategy for the eradication of cancer stem cells, via differentiation-based nano-therapy.

  16. Inorganic carbon acquisition in potentially toxic and non-toxic diatoms: the effect of pH-induced changes in the seawater carbonate chemistry

    DEFF Research Database (Denmark)

    Trimborn, S; Lundholm, Nina; Thoms, S;

    2008-01-01

    The effects of pH-induced changes in seawater carbonate chemistry on inorganic carbon (C-i) acquisition and domoic acid (DA) production were studied in two potentially toxic diatom species, Pseudo-nitzschia multiseries and Nitzschia navis-varingica, and the non-toxic Stellarima stellaris. In vivo......, it was about 55% in P. multiseries and only approximately 30% in N. navis-varingica. The intracellular content of DA increased in P. multiseries and N. navis-varingica with increasing pH. Based on our data, we propose a novel role for eCA acting as C-i-recycling mechanism. With regard to p...

  17. Crystals of phospholipase A2 inhibitor. The non-toxic component of vipoxin from the venom of Bulgarian viper (Vipera ammodytes).

    Science.gov (United States)

    Devedjiev, Y; Atanasov, B; Mancheva, I; Aleksiev, B

    1993-02-20

    Phospholipase A2 inhibitor, the non-toxic, acidic component of vipoxin from the venom of Bulgarian viper (Vipera ammodytes), has been crystallized. The tetragonal crystals obtained, exhibit the symmetry of space group P4(1)22 (or 4(3)22) with unit cell dimensions a = b = 59.9 A; c = 141.1 A; alpha = beta = gamma = 90 degrees. For two molecules per asymmetric unit, this would give Vm = 2.3 A3/Da, indicating normal packing. The crystals diffract to 2.5 A and a native data set to 3.2 A resolution has been collected.

  18. Thermal Comfort and Optimum Humidity Part 1

    Directory of Open Access Journals (Sweden)

    M. V. Jokl

    2002-01-01

    Full Text Available The hydrothermal microclimate is the main component in indoor comfort. The optimum hydrothermal level can be ensured by suitable changes in the sources of heat and water vapor within the building, changes in the environment (the interior of the building and in the people exposed to the conditions inside the building. A change in the heat source and the source of water vapor involves improving the heat - insulating properties and the air permeability of the peripheral walls and especially of the windows. The change in the environment will bring human bodies into balance with the environment. This can be expressed in terms of an optimum or at least an acceptable globe temperature, an adequate proportion of radiant heat within the total amount of heat from the environment (defined by the difference between air and wall temperature, uniform cooling of the human body by the environment, defined a by the acceptable temperature difference between head and ankles, b by acceptable temperature variations during a shift (location unchanged, or during movement from one location to another without a change of clothing. Finally, a moisture balance between man and the environment is necessary (defined by acceptable relative air humidity. A change for human beings means a change of clothes which, of course, is limited by social acceptance in summer and by inconvenient heaviness in winter. The principles of optimum heating and cooling, humidification and dehumidification are presented in this paper.Hydrothermal comfort in an environment depends on heat and humidity flows (heat and water vapors, occurring in a given space in a building interior and affecting the total state of the human organism.

  19. Thermal Comfort and Optimum Humidity Part 2

    Directory of Open Access Journals (Sweden)

    M. V. Jokl

    2002-01-01

    Full Text Available The hydrothermal microclimate is the main component in indoor comfort. The optimum hydrothermal level can be ensured by suitable changes in the sources of heat and water vapor within the building, changes in the environment (the interior of the building and in the people exposed to the conditions inside the building. A change in the heat source and the source of water vapor involves improving the heat - insulating properties and the air permeability of the peripheral walls and especially of the windows. The change in the environment will bring human bodies into balance with the environment. This can be expressed in terms of an optimum or at least an acceptable globe temperature, an adequate proportion of radiant heat within the total amount of heat from the environment (defined by the difference between air and wall temperature, uniform cooling of the human body by the environment, defined a by the acceptable temperature difference between head and ankles, b by acceptable temperature variations during a shift (location unchanged, or during movement from one location to another without a change of clothing. Finally, a moisture balance between man and the environment is necessary (defined by acceptable relative air humidity. A change for human beings means a change of clothes which, of course, is limited by social acceptance in summer and by inconvenient heaviness in winter. The principles of optimum heating and cooling, humidification and dehumidification are presented in this paper.Hydrothermal comfort in an environment depends on heat and humidity flows (heat and water vapors, occurring in a given space in a building interior and affecting the total state of the human organism.

  20. Optimum Route Selection for Vehicle Navigation

    Directory of Open Access Journals (Sweden)

    Dalip

    2016-02-01

    Full Text Available The objective of Optimum Route Selection for Vehicle Navigation System (ORSVNS article is to develop a system, which provides information about real time alternate routes to the drivers and also helps in selecting the optimal route among all the alternate routes from an origin to destination. Two types of query systems, special and general, are designed for drivers. Here, the criterion for route selection is introduced using primary and secondary road attributes. The presented methodology helps the drivers in better decision making to choose optimal route using fuzzy logic. For experimental results ORSVNS is tested over 220 km portion of Haryana state in India.

  1. Optimum Staging with Varying Thrust Attitude Angle

    Directory of Open Access Journals (Sweden)

    T. N. Srivastava

    1966-07-01

    Full Text Available Optimum staging programme for step rockets of arbitrary number of stages having different specific impulses and mass fractions with stages is derived, the optimization criterion being minimum take-off weight for a desired burntout velocity at an assigned altitude. Variation of thrust attitude angle from stage to stage and effects of gravity factor are taken into account. Analysis is performed for a degenerate problem obtained by relaxing the altitude constraint and it has been shown that problems of Weisbord, Subotowicz, Hall & Zambelli and Malina & Summerfield are the particular cases of the degenerate problem.

  2. Non-Toxic Metabolic Management of Metastatic Cancer in VM Mice: Novel Combination of Ketogenic Diet, Ketone Supplementation, and Hyperbaric Oxygen Therapy.

    Science.gov (United States)

    Poff, A M; Ward, N; Seyfried, T N; Arnold, P; D'Agostino, D P

    2015-01-01

    The Warburg effect and tumor hypoxia underlie a unique cancer metabolic phenotype characterized by glucose dependency and aerobic fermentation. We previously showed that two non-toxic metabolic therapies - the ketogenic diet with concurrent hyperbaric oxygen (KD+HBOT) and dietary ketone supplementation - could increase survival time in the VM-M3 mouse model of metastatic cancer. We hypothesized that combining these therapies could provide an even greater therapeutic benefit in this model. Mice receiving the combination therapy demonstrated a marked reduction in tumor growth rate and metastatic spread, and lived twice as long as control animals. To further understand the effects of these metabolic therapies, we characterized the effects of high glucose (control), low glucose (LG), ketone supplementation (βHB), hyperbaric oxygen (HBOT), or combination therapy (LG+βHB+HBOT) on VM-M3 cells. Individually and combined, these metabolic therapies significantly decreased VM-M3 cell proliferation and viability. HBOT, alone or in combination with LG and βHB, increased ROS production in VM-M3 cells. This study strongly supports further investigation into this metabolic therapy as a potential non-toxic treatment for late-stage metastatic cancers.

  3. Non-Toxic Metabolic Management of Metastatic Cancer in VM Mice: Novel Combination of Ketogenic Diet, Ketone Supplementation, and Hyperbaric Oxygen Therapy.

    Directory of Open Access Journals (Sweden)

    A M Poff

    Full Text Available The Warburg effect and tumor hypoxia underlie a unique cancer metabolic phenotype characterized by glucose dependency and aerobic fermentation. We previously showed that two non-toxic metabolic therapies - the ketogenic diet with concurrent hyperbaric oxygen (KD+HBOT and dietary ketone supplementation - could increase survival time in the VM-M3 mouse model of metastatic cancer. We hypothesized that combining these therapies could provide an even greater therapeutic benefit in this model. Mice receiving the combination therapy demonstrated a marked reduction in tumor growth rate and metastatic spread, and lived twice as long as control animals. To further understand the effects of these metabolic therapies, we characterized the effects of high glucose (control, low glucose (LG, ketone supplementation (βHB, hyperbaric oxygen (HBOT, or combination therapy (LG+βHB+HBOT on VM-M3 cells. Individually and combined, these metabolic therapies significantly decreased VM-M3 cell proliferation and viability. HBOT, alone or in combination with LG and βHB, increased ROS production in VM-M3 cells. This study strongly supports further investigation into this metabolic therapy as a potential non-toxic treatment for late-stage metastatic cancers.

  4. Structures and antifouling properties of low surface energy non-toxic antifouling coatings modified by nano-SiO2 powder

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Antifouling coatings are used to improve the speed and energy efficiency of ships by preventing or- ganisms, such as barnacles and weed, building up on the underwater hull and helping the ships movement through the water. Typically, marine coatings are tributyltin self-polishing copolymer paints containing toxic molecules called biocides. They have been the most successful in combating bio- fouling on ships, but their widespread use has caused severe pollution in the marine ecosystem. The low surface energy marine coating is an entirely non-toxic alternative, which reduces the adhesion strength of marine organisms, facilitating their hydrodynamic removal at high speeds. In this paper, the novel low surface energy non-toxic marine antifouling coatings were prepared with modified acrylic resin, nano-SiO2, and other pigments. The effects of nano-SiO2 on the surface structure and elastic modulus of coating films have been studied, and the seawater test has been carried out in the Dalian Bay. The results showed that micro-nano layered structures on the coating films and the lowest surface energy and elastic modulus could be obtained when an appropriate mass ratio of resin, nano-SiO2, and other pigments in coatings approached. The seawater exposure test has shown that the lower the sur- face energy and elastic modulus of coatings are, the less the marine biofouling adheres on the coating films.

  5. Structures and antifouling properties of low surface energy non-toxic antifouling coatings modified by nano-SiO2 powder

    Institute of Scientific and Technical Information of China (English)

    CHEN MeiLing; QU YuanYuan; YANG Li; GAO Hong

    2008-01-01

    Antifouling coatings are used to improve the speed and energy efficiency of ships by preventing or-ganisms, such as barnacles and weed, building up on the underwater hull and helping the ships movement through the water. Typically, marine coatings are tributyltin self-polishing copolymer paints containing toxic molecules called biocides. They have been the most successful in combating bio-fouling on ships, but their widespread use has caused severe pollution in the marine ecosystem. The low surface energy marine coating is an entirely non-toxic alternative, which reduces the adhesion strength of marine organisms, facilitating their hydrodynamic removal at high speeds. In this paper, the novel low surface energy non-toxic marine antifouling coatings were prepared with modified acrylic resin, nano-SiO2, and other pigments. The effects of nano-SiO2 on the surface structure and elastic modulus of coating films have been studied, and the seawater test has been carried out in the Dalian Bay. The results showed that micro-nano layered structures on the coating films and the lowest surface energy and elastic modulus could be obtained when an appropriate mass ratio of resin, nano-SiO2, and other pigments in coatings approached. The seawater exposure test has shown that the lower the sur-face energy and elastic modulus of coatings are, the less the marine biofouling adheres on the coating films.

  6. REGARDING "TRAGIC ECONOMIC OPTIMUM" FROM HOLISTIC+ PERSPECTIVE

    Directory of Open Access Journals (Sweden)

    Constantin Popescu

    2010-12-01

    Full Text Available Communication aims to discuss the new scientific vision of "the entire integrated" as it follows the recent achievements of quantum physics, psychology and biology. From this perspective, economy is seen as a living organism, part of the social organism and together with de bright ecology. The optimum of the economy as a living organism is based on dynamic compatibilities with all common living requirements. The evolution of economic life is organically linked to the unavoidable circumstances contained in the form of V. Frankl ‘s tragic triad consisting of: pain, guilt and death. In interaction with the holistic triad circumscribed by limitations, uncertainties and open interdependencies, the tragic economic optimum (TEO is formed. It can be understood as that state of economic life in which freedom of choice of scarce resources under uncertainty has in the compatibility of rationality and hope the development criteria of MEANING. TEO means to say YES to economic life even in conditions of resource limitations, bankruptcies and unemployment, negative externalities, stress, etc. By respiritualization of responsibility using scientific knowledge. TEO - involves multicriteria modeling of economic life by integrating human demands, community, environmental, spiritual and business development in the assessment predicting human GDP as a variable wave aggregate.

  7. Biological chip technology to quickly batch select optimum cryopreservation procedure

    Institute of Scientific and Technical Information of China (English)

    YU Lina; LIU Jing; ZHOU Yixin; HUA Zezhao

    2007-01-01

    In the practices of cryobiology,selection of an optimum freeze/thawing program and an idealistic cryoprotective agent often requires rather tedious,time consuming and repetitive tests.Integrating the functions of sample preparation and viability detection,the concept of biochip technology was introduced to the field of cryopreservation,aiming at quickly finding an optimum freezing and thawing program.Prototype devices were fabricated and corresponding experimental tests were performed.It was shown that microflow-channel chip could not offer a high quality solution distribution.As an alternative,the spot-dropping chip proved to be an excellent way to load the sample quickly and reliably.Infrared thermal mapping on such a chip showed that it had a rather uniform heat transfer boundary.Applying the spot-dropping chip combined with the thermoelectric cooling device,the final output of cryopreservation of multiple samples was tested,and the optimal freeze/thawing program as well as the potentially best concentration of the cryoprotective agent was found by analyzing the results.Further,application of this technique to measure the thermo-physical properties of the cryo-protective agent was also investigated.The study demonstrated that a biochip with integrated automatic loading and inspection units opens the possibility of a massive optimization of the complex cryopreservation program in a quicker and more economical way.

  8. Development of SCAR marker specific to non-toxic Jatropha curcas L. and designing a novel multiplexing PCR along with nrDNA ITS primers to circumvent the false negative detection

    KAUST Repository

    Mastan, Shaik G.

    2011-05-10

    Jatropha curcas L., a multipurpose shrub, has acquired significant economic importance for its seed oil which can be converted to biodiesel an emerging alternative to petro-diesel. In addition to the commercial value, it is also having medicinal and even high nutritional value to use as animal fodder which is limited due to the toxicity. Development of molecular marker will enable to differentiate non-toxic from toxic variety of J. curcas in a mixed population and also for quality control since the toxic components of J. curcas has deleterious effect on animals. In the present study, the efforts were made to generate the specific SCAR marker for toxic and/or non-toxic J. curcas from RAPD markers. Among the markers specific for toxic and non-toxic varieties, four were selected, purified, cloned, sequenced, and designed primers out of which one set of primers NT-JC/SCAR I/OPQ15-F and R could able to discriminate the non-toxic with toxic Jatropha by giving expected 430 bp size amplification in non-toxic variety. Furthermore, novel multiplex PCR was designed using the nrDNA ITS primers to overcome the false negatives. Present work also demonstrates utility of the conserved regions of nrDNA coding genes in ruling out the artifacts in PCR-like false negatives frequently occur in SCAR due to various reasons. The specific SCAR markers generated in the present investigation will help to distinguish non-toxic from toxic varieties of J. curcas or vice versa, and isolated marker along with designed multiplex protocol has applications in quality control for selective cultivation of non-toxic variety and will also assist in breeding and molecular mapping studies. © 2011 Springer Science+Business Media, LLC.

  9. Design optimum frac jobs using virtual intelligence techniques

    Science.gov (United States)

    Mohaghegh, Shahab; Popa, Andrei; Ameri, Sam

    2000-10-01

    Designing optimal frac jobs is a complex and time-consuming process. It usually involves the use of a two- or three-dimensional computer model. For the computer models to perform as intended, a wealth of input data is required. The input data includes wellbore configuration and reservoir characteristics such as porosity, permeability, stress and thickness profiles of the pay layers as well as the overburden layers. Among other essential information required for the design process is fracturing fluid type and volume, proppant type and volume, injection rate, proppant concentration and frac job schedule. Some of the parameters such as fluid and proppant types have discrete possible choices. Other parameters such as fluid and proppant volume, on the other hand, assume values from within a range of minimum and maximum values. A potential frac design for a particular pay zone is a combination of all of these parameters. Finding the optimum combination is not a trivial process. It usually requires an experienced engineer and a considerable amount of time to tune the parameters in order to achieve desirable outcome. This paper introduces a new methodology that integrates two virtual intelligence techniques, namely, artificial neural networks and genetic algorithms to automate and simplify the optimum frac job design process. This methodology requires little input from the engineer beyond the reservoir characterizations and wellbore configuration. The software tool that has been developed based on this methodology uses the reservoir characteristics and an optimization criteria indicated by the engineer, for example a certain propped frac length, and provides the detail of the optimum frac design that will result in the specified criteria. An ensemble of neural networks is trained to mimic the two- or three-dimensional frac simulator. Once successfully trained, these networks are capable of providing instantaneous results in response to any set of input parameters. These

  10. Towards the Optimum Light Source Spectrum

    Directory of Open Access Journals (Sweden)

    Andrew Chalmers

    2010-01-01

    Full Text Available This paper is concerned with designing light source spectra for optimum luminous efficacy and colour rendering. We demonstrate that it is possible to design light sources that can provide both good colour rendering and high luminous efficacy by combining the outputs of a number of narrowband spectral constituents. Also, the achievable results depend on the numbers and wavelengths of the different spectral bands utilized in the mixture. Practical realization of these concepts has been demonstrated in this pilot study which combines a number of simulations with tests using real LEDs (light emitting diodes. Such sources are capable of providing highly efficient lighting systems with good energy conservation potential. Further research is underway to investigate the practicalities of our proposals in relation to large-scale light source production.

  11. Optimum Maintenance Strategies for Highway Bridges

    DEFF Research Database (Denmark)

    Frangopol, Dan M.; Thoft-Christensen, Palle; Das, Parag C.;

    As bridges become older and maintenance costs become higher, transportation agencies are facing challenges related to implementation of optimal bridge management programs based on life cycle cost considerations. A reliability-based approach is necessary to find optimal solutions based on minimum...... expected life-cycle costs or maximum life-cycle benefits. This is because many maintenance activities can be associated with significant costs, but their effects on bridge safety can be minor. In this paper, the program of an investigation on optimum maintenance strategies for different bridge types...... is described. The end result of this investigation will be a general reliability-based framework to be used by the UK Highways Agency in order to plan optimal strategies for the maintenance of its bridge network so as to optimize whole-life costs....

  12. Choosing an optimum sand control method

    Directory of Open Access Journals (Sweden)

    Ehsan Khamehchi

    2015-06-01

    Full Text Available Formation sand control is always one of the main concerns of production engineers. There are some different methods to prevent sand production. Choosing a method for preventing formation sand production depends on different reservoir parameters and politic and economic conditions. Sometimes, economic and politic conditions are more effective to choose an optimum than reservoir parameters. Often, simultaneous investigation of politic and economic conditions with reservoir parameters has different results with what is expected. So, choosing the best sand control method is the result of thorough study. Global oil price, duration of sand control project and costs of necessary equipment for each method as economic and politic conditions and well productivity index as reservoir parameter are the main parameters studied in this paper.

  13. Current Situation and Development of New Non-toxic Antifouling Coating%新型无毒防污涂料的发展现状

    Institute of Scientific and Technical Information of China (English)

    王威; 晏欣; 孙卫红

    2011-01-01

    自含锡防污涂料被禁止使用以来,无毒环保型防污涂料有了很大的发展.本文综述了一些无锡自抛光防污涂料以及用有机硅改性的丙烯酸和聚氨酯涂料,并做了展望.%It is a long time to use antifouling coating on the boat, since Tributyltin self-polishing antifouling coating(TBT-SPC)was ban, environment friendly and non-toxic antifouling coating has develop greatly. This text summarizes some kinds of tin-freeself-polishing antifouling coating, acrylic resin coating, and polyurethane coating which were chemically modified by organic si-loxane.

  14. Bacillus subtilis natto: a non-toxic source of poly-γ-glutamic acid that could be used as a cryoprotectant for probiotic bacteria.

    Science.gov (United States)

    Bhat, Aditya R; Irorere, Victor U; Bartlett, Terry; Hill, David; Kedia, Gopal; Morris, Mark R; Charalampopoulos, Dimitris; Radecka, Iza

    2013-07-05

    It is common practice to freeze dry probiotic bacteria to improve their shelf life. However, the freeze drying process itself can be detrimental to their viability. The viability of probiotics could be maintained if they are administered within a microbially produced biodegradable polymer - poly-γ-glutamic acid (γ-PGA) - matrix. Although the antifreeze activity of γ-PGA is well known, it has not been used for maintaining the viability of probiotic bacteria during freeze drying. The aim of this study was to test the effect of γ-PGA (produced by B. subtilis natto ATCC 15245) on the viability of probiotic bacteria during freeze drying and to test the toxigenic potential of B. subtilis natto. 10% γ-PGA was found to protect Lactobacillus paracasei significantly better than 10% sucrose, whereas it showed comparable cryoprotectant activity to sucrose when it was used to protect Bifidobacterium breve and Bifidobacterium longum. Although γ-PGA is known to be non-toxic, it is crucial to ascertain the toxigenic potential of its source, B. subtilis natto. Presence of six genes that are known to encode for toxins were investigated: three component hemolysin (hbl D/A), three component non-haemolytic enterotoxin (nheB), B. cereus enterotoxin T (bceT), enterotoxin FM (entFM), sphingomyelinase (sph) and phosphatidylcholine-specific phospholipase (piplc). From our investigations, none of these six genes were present in B. subtilis natto. Moreover, haemolytic and lecithinase activities were found to be absent. Our work contributes a biodegradable polymer from a non-toxic source for the cryoprotection of probiotic bacteria, thus improving their survival during the manufacturing process.

  15. Keampferol-3-O-rhamnoside abrogates amyloid beta toxicity by modulating monomers and remodeling oligomers and fibrils to non-toxic aggregates

    Directory of Open Access Journals (Sweden)

    Sharoar Md

    2012-12-01

    Full Text Available Abstract Background Aggregation of soluble, monomeric β- amyloid (Aβ to oligomeric and then insoluble fibrillar Aβ is a key pathogenic feature in development of Alzheimer’s disease (AD. Increasing evidence suggests that toxicity is linked to diffusible Aβ oligomers, rather than to insoluble fibrils. The use of naturally occurring small molecules for inhibition of Aβ aggregation has recently attracted significant interest for development of effective therapeutic strategies against the disease. A natural polyphenolic flavone, Kaempferol-3-O-rhamnoside (K-3-rh, was utilized to investigate its effects on aggregation and cytotoxic effects of Aβ42 peptide. Several biochemical techniques were used to determine the conformational changes and cytotoxic effect of the peptide in the presence and absence of K-3-rh. Results K-3-rh showed a dose-dependent effect against Aβ42 mediated cytotoxicity. Anti-amyloidogenic properties of K-3-rh were found to be efficient in inhibiting fibrilogenesis and secondary structural transformation of the peptide. The consequence of these inhibitions was the accumulation of oligomeric structural species. The accumulated aggregates were smaller, soluble, non-β-sheet and non-toxic aggregates, compared to preformed toxic Aβ oligomers. K-3-rh was also found to have the remodeling properties of preformed soluble oligomers and fibrils. Both of these conformers were found to remodel into non-toxic aggregates. The results showed that K-3-rh interacts with different Aβ conformers, which affects fibril formation, oligomeric maturation and fibrillar stabilization. Conclusion K-3-rh is an efficient molecule to hinder the self assembly and to abrogate the cytotoxic effects of Aβ42 peptide. Hence, K-3-rh and small molecules with similar structure might be considered for therapeutic development against AD.

  16. Induction and transfer of resistance to poisoning by Amorimia pubiflora in sheep whith non-toxic dosis of the plant and ruminal content

    Directory of Open Access Journals (Sweden)

    Marciel Becker

    2016-04-01

    Full Text Available ABSTRACT: Amorimiapubiflora (Malpighiaceae, which contains sodium monofluoroacetate (MFA is the main cause of "sudden death" in cattle in the Brazilian state of Mato Grosso. This research investigated the induction of resistance to the poisoning in sheep by the continuous administration of non-toxic doses of the plant and also the possibility to transfer this resistance to other sheep by the transfaunation of ruminal fluid. For this a group of four sheep (G1 received daily doses of 0.5g kg-1 for 20 days and after an interval of 15 days were challenged with three daily doses of 1g kg-1 for 3 days. Also the transfer of resistance to A. pubiflora poisoning was evaluated by transfaunation of rumen fluid (100ml for 10 days from G1 sheep to five sheep (G2, followed by challenge with the dose of 1g kg-1 for 3 days (G2D2 and after a three-day interval they received a single dose of 3g kg-1 (G2D3. The degree of resistance was evaluated by monitoring the onset of clinical signs, heart rate, and outcome of the poisoning compared with the control groups, which were challenged with three daily doses of 1g kg1 (G3 and with a single dose of 3g kg-1 (G4. Clinical parameters evaluated in Groups G1 and G2 were significantly less pronounced than those observed in G3 and G4 (control (P<0.05. Sheep in G4 (control died after receiving a single dose of 3g kg-1, while those in G2 (transfaunated survived. These findings demonstrated that consumption of non-toxic doses of A. pubiflora induced resistance in sheep and that this resistance can be transferred by transfaunation. New experiments are needed to determine the most efficient ways to induce resistance and to use this technique in the field to prevent the poisoning.

  17. Optimum Design of Structure Shape for Offshore Jacket Platforms

    Institute of Scientific and Technical Information of China (English)

    FENG Sheng; SONG Yupu; ZHANG Rixiang

    2000-01-01

    With the introduction of the design variables of nodal coordinates, which reflect the embedded depth of the pile and the jacket bed height, a shape optimum design model for offshore jacket platforms is established. A sequential two-level optimum algorithm is developed based on the design variable gradation. On the basis of the finite element method, the sensitivity of the objective function and nodal displacement is analyzed. As an example, the BZ281 oil storage offshore platform, which lies in the Bohai oil field, is designed with the shape optimum model The results are compared with the cross-section optimum design. The tendency of design variables and its reasons in the two methods are analyzed. In the shape optimum design, the value of objective function is obviously smaller than that of the initial design and the cross-section optimum design. Therefore, the advantage of structure shape optimum design for jacket platforms is remarkable.

  18. Exploring the optimum conditions for maximizing the microbial growth of Candida intermedia by response surface methodology.

    Science.gov (United States)

    Yönten, Vahap; Aktaş, Nahit

    2014-01-01

    Exploring optimum and cost-efficient medium composition for microbial growth of Candida intermedia Y-1981 yeast culture growing on whey was studied by applying a multistep response surface methodology. In the first step, Plackett-Burman (PB) design was utilized to determine the most significant fermentation medium factors on microbial growth. The medium temperature, sodium chloride and lactose concentrations were determined as the most important factors. Subsequently, the optimum combinations of the selected factors were explored by steepest ascent (SA) and central composite design (CCD). The optimum values for lactose and sodium chloride concentrations and medium temperature were found to be 18.4 g/L, 0.161 g/L, and 32.4°C, respectively. Experiments carried out at the optimum conditions revealed a maximum specific growth rate of 0.090 1/hr; 42% of total lactose removal was achieved in 24 h of fermentation time. The obtained results were finally verified with batch reactor experiments carried out under the optimum conditions evaluated.

  19. Optimum harvest maturity for Leymus chinensis seed

    Directory of Open Access Journals (Sweden)

    Jixiang Lin

    2016-06-01

    Full Text Available Timely harvest is critical to achieve maximum seed viability and vigour in agricultural production. However, little information exists concerning how to reap the best quality seeds of Leymus chinensis, which is the dominant and most promising grass species in the Songnen Grassland of Northern China. The objective of this study was to investigate and evaluate possible quality indices of the seeds at different days after peak anthesis. Seed quality at different development stages was assessed by the colours of the seed and lemmas, seed weight, moisture content, electrical conductivity of seed leachate and germination indices. Two consecutive years of experimental results showed that the maximum seed quality was recorded at 39 days after peak anthesis. At this date, the colours of the seed and lemmas reached heavy brown and yellow, respectively. The seed weight was highest and the moisture content and the electrical conductivity of seed leachate were lowest. In addition, the seed also reached its maximum germination percentage and energy at this stage, determined using a standard germination test (SGT and accelerated ageing test (AAT. Thus, Leymus chinensis can be harvested at 39 days after peak anthesis based on the changes in parameters. Colour identification can be used as an additional indicator to provide a more rapid and reliable measure of optimum seed maturity; approximately 10 days after the colour of the lemmas reached yellow and the colour of the seed reached heavy brown, the seed of this species was suitable for harvest.

  20. Optimum Energy Window In Liver Scintigraphy

    Directory of Open Access Journals (Sweden)

    Alireza Sadremomtaz

    2015-07-01

    Full Text Available Abstract In liver scintigraphy radioactive tracers in addition to liver are accumulated in other organs such as spleen. It leads to the presence of secondary source which affects image quality. Therefore knowing the influence of the noise arising from the secondary source and trying to reduce the additional data is necessary. In nuclear medicine imaging using of energy window is a useful way to reduce the noise. In this paper we try to find an optimum energy window to reduce the noise for two different low energy collimators. Liver scintigraphy images with and without activity in spleen were simulated by SIMIND software with different energy window percentages and with Low-Energy High-Resolution LEHR and Low-Energy General-Purpose LEGP collimators. We used with activity of 190 MBq. Spleen was outside of the camera field of view so that just its noise effects on the liver image is examined. Finally the images of liver with activity in spleen were compared with that without activity in spleen by MATLAB code.

  1. Optimum size of nanorods for heating application

    Energy Technology Data Exchange (ETDEWEB)

    Seshadri, G., E-mail: seshg@stanford.edu; Thaokar, Rochish; Mehra, Anurag

    2014-08-01

    Magnetic nanoparticles (MNP's) have become increasingly important in heating applications such as hyperthermia treatment of cancer due to their ability to release heat when a remote external alternating magnetic field is applied. It has been shown that the heating capability of such particles varies significantly with the size of particles used. In this paper, we theoretically evaluate the heating capability of rod-shaped MNP's and identify conditions under which these particles display highest efficiency. For optimally sized monodisperse particles, the power generated by rod-shaped particles is found to be equal to that generated by spherical particles. However, for particles which are not mono dispersed, rod-shaped particles are found to be more effective in heating as a result of the greater spread in the power density distribution curve. Additionally, for rod-shaped particles, a dispersion in the radius of the particle contributes more to the reduction in loss power when compared to a dispersion in the length. We further identify the optimum size, i.e the radius and length of nanorods, given a bi-variate log-normal distribution of particle size in two dimensions. - Highlights: • Theoretically estimated loss power of magnetic nanorods. • Compared the heat generation by nanorods and nano-spheres. • Incorporated size distribution of particles into calculations. • Nanorods are more efficient than nano-spheres for heating. • 2D heat maps for optimizing size of nanorods for heating.

  2. Optimum Currency Area Criteria in the Greece

    Directory of Open Access Journals (Sweden)

    Milovan Rankov

    2013-08-01

    Full Text Available Creation of a monetary union in any region, regardless of the structure and level of development among countries, carries along certain costs and benefits. This paper explains Mundell’s concept of Optimum Currency Area and criteria that are needed to achieve it. Viewed through the prism of these criteria the EMU is currently far from achieving the OCA confirming the current crisis in Greece and other PIIGS countries. The example of Greece and shortcomings that contributed to its current crisis represents the biggest cost and a break-even point for the future of the monetary union. However, it is encouraging that Greece is not alone in its problems, since various funds for help have been established in a relatively short period of time. The reason for this is certainly a huge cost if any country should leave the union and the spillover effect that it would cause. Certainly serious transformations can be expected and the result should be a stronger union with better control from supra-national level.

  3. Achieving optimum diffraction based overlay performance

    Science.gov (United States)

    Leray, Philippe; Laidler, David; Cheng, Shaunee; Coogans, Martyn; Fuchs, Andreas; Ponomarenko, Mariya; van der Schaar, Maurits; Vanoppen, Peter

    2010-03-01

    Diffraction Based Overlay (DBO) metrology has been shown to have significantly reduced Total Measurement Uncertainty (TMU) compared to Image Based Overlay (IBO), primarily due to having no measurable Tool Induced Shift (TIS). However, the advantages of having no measurable TIS can be outweighed by increased susceptibility to WIS (Wafer Induced Shift) caused by target damage, process non-uniformities and variations. The path to optimum DBO performance lies in having well characterized metrology targets, which are insensitive to process non-uniformities and variations, in combination with optimized recipes which take advantage of advanced DBO designs. In this work we examine the impact of different degrees of process non-uniformity and target damage on DBO measurement gratings and study their impact on overlay measurement accuracy and precision. Multiple wavelength and dual polarization scatterometry are used to characterize the DBO design performance over the range of process variation. In conclusion, we describe the robustness of DBO metrology to target damage and show how to exploit the measurement capability of a multiple wavelength, dual polarization scatterometry tool to ensure the required measurement accuracy for current and future technology nodes.

  4. On Optimum Causal Cognitive Spectrum Reutilization Strategy

    CERN Document Server

    Haghighi, Kasra; Agrell, Erik

    2011-01-01

    In this paper we study opportunistic transmission strategies for cognitive radios (CR) in which causal noisy observation from a primary user(s) (PU) state is available. PU is assumed to be operating in a slotted manner, according to a two-state Markov model. The objective is to maximize utilization ratio (UR), i.e., relative number of the PU-idle slots that are used by CR, subject to interference ratio (IR), i.e., relative number of the PU-active slots that are used by CR, below a certain level. We introduce an a-posteriori LLR-based cognitive transmission strategy and show that this strategy is optimum in the sense of maximizing UR given a certain maximum allowed IR. Two methods for calculating threshold for this strategy in practical situations are presented. One of them performs well in higher SNRs but might have too large IR at low SNRs and low PU activity levels, and the other is proven to never violate the allowed IR at the price of a reduced UR. In addition, an upper-bound for the UR of any CR strategy...

  5. Optimum harvest maturity for Leymus chinensis seed

    Science.gov (United States)

    Lin, Jixiang; Wang, Yingnan; Qi, Mingming; Li, Xiaoyu; Yang, Chunxue; Wang, Yongcui

    2016-01-01

    ABSTRACT Timely harvest is critical to achieve maximum seed viability and vigour in agricultural production. However, little information exists concerning how to reap the best quality seeds of Leymus chinensis, which is the dominant and most promising grass species in the Songnen Grassland of Northern China. The objective of this study was to investigate and evaluate possible quality indices of the seeds at different days after peak anthesis. Seed quality at different development stages was assessed by the colours of the seed and lemmas, seed weight, moisture content, electrical conductivity of seed leachate and germination indices. Two consecutive years of experimental results showed that the maximum seed quality was recorded at 39 days after peak anthesis. At this date, the colours of the seed and lemmas reached heavy brown and yellow, respectively. The seed weight was highest and the moisture content and the electrical conductivity of seed leachate were lowest. In addition, the seed also reached its maximum germination percentage and energy at this stage, determined using a standard germination test (SGT) and accelerated ageing test (AAT). Thus, Leymus chinensis can be harvested at 39 days after peak anthesis based on the changes in parameters. Colour identification can be used as an additional indicator to provide a more rapid and reliable measure of optimum seed maturity; approximately 10 days after the colour of the lemmas reached yellow and the colour of the seed reached heavy brown, the seed of this species was suitable for harvest. PMID:27170257

  6. An Optimum Solution for Electric Power Theft

    Directory of Open Access Journals (Sweden)

    Aamir Hussain Memon

    2013-07-01

    Full Text Available Electric power theft is a problem that continues to plague power sector across the whole country. Every year, the electricity companies face the line losses at an average 20-30% and according to power ministry estimation WAPDA companies lose more than Rs. 125 billion. Significantly, it is enough to destroy the entire power sector of country. According to sources 20% losses means the masses would have to pay extra 20% in terms of electricity tariffs. In other words, the innocent consumers pay the bills of those who steal electricity. For all that, no any permanent solution for this major issue has ever been proposed. We propose an applicable and optimum solution for this impassable problem. In our research, we propose an Electric power theft solution based on three stages; Transmission stage, Distribution stage, and User stage. Without synchronization among all, the complete solution can not be achieved. The proposed solution is simulated on NI (National Instruments Circuit Design Suite Multisim v.10.0. Our research work is an implicit and a workable approach towards the Electric power theft, as for conditions in Pakistan, which is bearing the brunt of power crises already

  7. Testicular Busulfan Injection in Mice to Prepare Recipients for Spermatogonial Stem Cell Transplantation Is Safe and Non-Toxic.

    Directory of Open Access Journals (Sweden)

    YuSheng Qin

    Full Text Available Current methods of administering busulfan to remove the endogenous germ cells cause hematopoietic toxicity, require special instruments and a narrow transplantation time. We use a direct testicular injection of busulfan method for preparing recipients for SSC transplantation. Male ICR mice (recipients were divided into four groups, and two experimental groups were treated with a bilateral testicular injection of 4 or 6 mg/kg/side busulfan (n = 60 per concentration group. Mice received an intraperitoneal injection (i.p. of 40 mg/kg busulfan (n = 60, positive control and bilateral testicular injections of 50% DMSO (n = 60, negative control. Donor SSCs from RFP-transgenic C57BL/6J mice were introduced into the seminiferous tubules of each recipient testis via efferent duct injection on day 16-17 after busulfan treatment. Recipient mice mated with mature female ICR mice and the number of progeny was recorded. The index detected at day 14, 21, 28, 35 and 70 after busulfan treatment. Blood analysis shows that the toxicity of busulfan treated groups was much lower than i.p. injection groups. Fertility was restored in mice treated with busulfan and donor-derived offspring were obtained after SSC transplantation. Our study indicated that intratesticular injection busulfan for the preparation of recipients in mice is safe and feasible.

  8. Corrosion and optimum corrosion protection potential offriction stir welded 5083-O Al alloy for leisure ship

    Institute of Scientific and Technical Information of China (English)

    Sung-Hyeon PARK; Jong-Shin KIM; Min-Su HAN; Seong-Jong KIM

    2009-01-01

    Electrochemical tests were undertaken to determine the optimum conditions in seawater for corrosion protection of friction stir-welded 5083-O Al alloy. Polarization trend observations show that the limiting potential that avoids the effects of hydrogen embrittlement is -1.6 V, corresponding to the crossover point between concentration polarization and activation polarization. However, the optimum protection potential is between -1.5 and -0.7 V since the current density at these values is low in the potentiostatic tests. When a galvanic cell is formed in the seawater, the welds exhibit electrochemically stable trends. Welded parts in galvanic tests with various area ratios are stable and have excellent anticorrosion characteristics.

  9. Evaluating the optimum rest period prior to blood collection for fractionated plasma free metanephrines analysis

    LENUS (Irish Health Repository)

    Griffin, T.P.

    2016-05-01

    The high diagnostic accuracy of plasma metanephrines (PMets) in the di-agnosis of Phaeochromocytoma\\/Paraganglioma (PPGL) is well established. Considerable controversy exists regarding optimum sampling conditions for PMets. The use of reference intervals that do not compromise diagnostic sensitivity is recommended. However, the optimum rest period prior to sampling has yet to be clearly established. The aim of this study was to evaluate PMets concentrations in paired blood samples collected following 30 and 40 min seated-rest prior to sampling, in patients in whom it was clinically rea-sonable to suspect that PPGL may be present.

  10. Design and construct optimum dosimeter to detect airborne radon and thoron gas: Experimental study

    Science.gov (United States)

    Ismail, Asaad H.; Jaafar, Mohamad S.

    2011-02-01

    Aim of this work is to design and select optimum dimension of a radon and thoron dosimeter within the measure optimum value of the calibration factor, using CR-39 Nuclear Track Detectors (NTDs). The results show that the best dimension to detect and measure real values of airborne radon and thoron concentrations is 6 cm and 7 cm for diameter and height, respectively. Calibration factors (K) for radon and thoron at this dimension were 2.68 ± 0.03 cm and 0.83 ± 0.01 cm, respectively, and these factors relatively depend on the detector efficiency. Therefore, the efficiency of CR-39NTDs to register alpha particles and their effects on the calibration factor estimated. It is found that the calibration factor increased exponentially with detector efficiency. Moreover, detector efficiency was equal to 80.3 ± 1.23% at the optimum dosimeter.

  11. Discovery of potent, novel, non-toxic anti-malarial compounds via quantum modelling, virtual screening and in vitro experimental validation

    Directory of Open Access Journals (Sweden)

    Kaludov Nikola

    2011-09-01

    Full Text Available Abstract Background Developing resistance towards existing anti-malarial therapies emphasize the urgent need for new therapeutic options. Additionally, many malaria drugs in use today have high toxicity and low therapeutic indices. Gradient Biomodeling, LLC has developed a quantum-model search technology that uses quantum similarity and does not depend explicitly on chemical structure, as molecules are rigorously described in fundamental quantum attributes related to individual pharmacological properties. Therapeutic activity, as well as toxicity and other essential properties can be analysed and optimized simultaneously, independently of one another. Such methodology is suitable for a search of novel, non-toxic, active anti-malarial compounds. Methods A set of innovative algorithms is used for the fast calculation and interpretation of electron-density attributes of molecular structures at the quantum level for rapid discovery of prospective pharmaceuticals. Potency and efficacy, as well as additional physicochemical, metabolic, pharmacokinetic, safety, permeability and other properties were characterized by the procedure. Once quantum models are developed and experimentally validated, the methodology provides a straightforward implementation for lead discovery, compound optimizzation and de novo molecular design. Results Starting with a diverse training set of 26 well-known anti-malarial agents combined with 1730 moderately active and inactive molecules, novel compounds that have strong anti-malarial activity, low cytotoxicity and structural dissimilarity from the training set were discovered and experimentally validated. Twelve compounds were identified in silico and tested in vitro; eight of them showed anti-malarial activity (IC50 ≤ 10 μM, with six being very effective (IC50 ≤ 1 μM, and four exhibiting low nanomolar potency. The most active compounds were also tested for mammalian cytotoxicity and found to be non-toxic, with a

  12. Intradermal immunization in the ear with cholera toxin and its non-toxic β subunit promotes efficient Th1 and Th17 differentiation dependent on migrating DCs.

    Science.gov (United States)

    Meza-Sánchez, David; Pérez-Montesinos, Gibrán; Sánchez-García, Javier; Moreno, José; Bonifaz, Laura C

    2011-10-01

    The nature of CD4(+) T-cell responses after skin immunization and the role of migrating DCs in the presence of adjuvants in the elicited response are interesting issues to be investigated. Here, we evaluated the priming of CD4(+) T cells following ear immunization with low doses of model antigens in combination with either cholera toxin (CT) or the non-toxic β CT subunit (CTB) as an adjuvant. Following immunization with CT, we found efficient antigen presentation that is reflected in the production of IFN-γ and IL-17 by CD4(+) T cells over IL-4 or IL-5 production. The CTB-induced activation of DCs in the ear occurred without visible inflammation, which reflects a similar type of CD4(+) T-cell differentiation. In both cases, the elicited response was dependent on the presence of migrating skin cells. Remarkably, immunization with CT or with CTB led to the induction of a delayed-type hypersensitivity (DTH) response in the ear. The DTH response that was induced by CT immunization was dependent on IL-17 and partially dependent on IFN-γ activity. These results indicate that both CT and CTB induce an efficient CD4(+) T-cell response to a co-administered antigen following ear immunization that is dependent on migrating DCs.

  13. First-principles study of photovoltaics and carrier mobility for non-toxic halide perovskite CH3NH3SnCl3: theoretical prediction.

    Science.gov (United States)

    Wang, Lin-Zhi; Zhao, Yu-Qing; Liu, Biao; Wu, Li-Juan; Cai, Meng-Qiu

    2016-08-10

    Promising candidates in this respect are organometal perovskites ABX3, which have been intensely investigated during the last years. In this paper, we calculate the crystal structures, optical properties and carrier mobility for three phases of non-toxic perovskite halide CH3NH3SnCl3 by applying density functional theory with the nonlocal van der Waals (vdW) correlation. The results show that CH3NH3SnCl3 has superior performance in terms of its optical absorption coefficient, which reaches as high as 10(5) cm(-1) and has proven itself to be a perfect solar light harvester. Most importantly, the results of intrinsic carrier mobility of CH3NH3SnCl3 show that the electron mobility of the triclinic phase can achieve a large magnitude of 1700 cm(2) V(-1) s(-1), which is mainly due to the small effective mass. We ascribe the superior photoelectric property to the ferroelectricity, which may be caused by the distorted octahedral SnCl6(-).

  14. Synthesis of Poly(N-vinyl-2-pyrrolidone-co-methyl methacrylate by Maghnite-H+ a Non-toxic Catalyst

    Directory of Open Access Journals (Sweden)

    Mohamed Benadda

    2014-10-01

    Full Text Available In the present work poly (N-vinyl-2-pyrrolidone-co-methyl methacrylate copolymers were prepared successfully and cleanly by a one step process via cationic copolymerization of N-vinyl-2-pyrrolidone (NVP with methyl methacrylate (MMA, in heterogeneous phase using “Maghnite-H+” (Mag-H+ as catalyst in bulk, Maghnite is a montmorillonite sheet silicate clay exchanged with protons to produce Maghnite-H+. Temperature is varied between 20 and 80 °C. The effects of reaction temperature, amount of Mag-H+ on the yield and the intrinsic viscosity (η were investigated. A typical reaction product of poly (NVP-co- MMA was analyzed by infra red spectroscopy (FTIR and 1H-NMR, 13C-NMR spectroscopy as well as by viscosimetry. © 2014 BCREC UNDIP. All rights reservedReceived: 24th November 2013; Revised: 30th June 2014; Accepted: 8th July 2014How to Cite: Benadda, M., Ferrahi, M.I., Belbachir, M. (2014. Synthesis of Poly(N-vinyl-2-pyrrolidone-co-methyl methacrylate by Maghnite-H+ a Non-toxic Catalyst. Bulletin of Chemical Reaction Engineering & Catalysis, 9 (3: 201-206. (doi: 10.9767/bcrec.9.3.5743.201-206Permalink/DOI: http://dx.doi.org/10.9767/bcrec.9.3.5743.201-206

  15. Non-toxic antifouling strategies

    Directory of Open Access Journals (Sweden)

    Chelsea M. Magin

    2010-04-01

    Full Text Available The term fouling generally refers to an undesirable process in which a surface becomes encrusted with material from the surrounding environment. In the case of biofouling, that material consists of organisms and their by-products e.g., extracellular polysaccharides and metabolites. Biofouling limits the performance of devices in numerous applications; however, this review focuses on antifouling biomaterials for marine and biomedical applications. The surface chemistry and physical properties of the substratum are both crucial to preventing the recruitment of biofouling organisms. Natural antifouling surfaces exhibit both chemical and physical attributes. The chemical structure is discussed briefly as it relates to both anti-fouling and fouling-release properties. However, our focus has been to study physical cues as they relate to the initial attachment of fouling organisms.

  16. Optimum operating regimes for the ideal wind turbine

    DEFF Research Database (Denmark)

    Okulov, Valery; Sørensen, Jens Nørkær

    2007-01-01

    We here present new results on the classical work of the optimum rotor. The emphasis is put vortex theory for which we have developed a new analytical method to determine the loading on an optimum win turbine rotor. The introduction of the work is a repetition of results using momentum theory...

  17. The optimum decision rules for the oddity task

    NARCIS (Netherlands)

    Versfeld, N.J.; Dai, H.; Green, D.M.

    1996-01-01

    This paper presents the optimum decision rule for an m-interval oddity task in which m-1 intervals contain the same signal and one is different or odd. The optimum decision rule depends on the degree of correlation among observations. The present approach unifies the different strategies that occur

  18. Development of optimum conditions for modification of Kpautagi clay for application in petroleum refinery wastewater treatment

    Directory of Open Access Journals (Sweden)

    Matthew A. ONU

    2015-12-01

    Full Text Available Kautagi clay is a kaolin type deposit that is abundantly available in Niger State, Nigeria with potential for application in pollution control such as wastewater treatment. This study investigates the optimum conditions for modification of Kpautagi clay for application in refinery wastewater treatment. Sulphuric acid was used in the modification of the clay and the modification variables considered were acid concentration, activation time and temperature. To develop the optimum conditions for the modification variables, the sulphuric acid modified Kpautagi clay was applied in the treatment of refinery wastewater in column mode at a fixed flow rate and mass of adsorbent. The results obtained indicate that the optimum conditions for modification of Kpautagi clay for application in the treatment of petroleum refinery wastewater are: acid concentration of 4M; activation time of 120min and activation temperature of 100°C. Therefore, the optimum conditions developed in this study for modification of Kpautagi clay could be applied for improved performance in the treatment of petroleum refinery wastewater.

  19. Selecting sprouts of brassicaceae for optimum phytochemical composition.

    Science.gov (United States)

    Baenas, Nieves; Moreno, Diego A; García-Viguera, Cristina

    2012-11-14

    Cruciferous foods (Brassicaceae spp.) are rich in nutrients and bioactive compounds. Edible sprouts are becoming popular fresh foods and, therefore, the phytochemical profiling of nine varieties of Brassicaceae (broccoli, kohlrabi, red cabbage, rutabaga, turnip, turnip greens, radish, garden cress, and white mustard) was evaluated for this purpose. The glucosinolates in seeds were significantly higher than in sprouts, and day 8 of germination was considered the optimum for consumption. The sprouts with higher concentrations of glucosinolates in 8-day-old sprouts were white mustard, turnip, and kohlrabi (∼815, ∼766, and ∼653 mg 100 g⁻¹ FW, respectively). Red cabbage and radish presented great total glucosinolates content (∼516 and ∼297 mg 100 g⁻¹ FW, respectively, in 8-day-old sprouts) and also higher total phenolic contents, biomass, and antioxidant capacity. The selection of the best performers in terms of germination quality and phytochemical composition is the key to optimize new fresh foods enriched in health-bioactive compounds. Further research on the bioavailability of the bioactive compounds in Brassica foods will allow backing of recommendations for dietarily effective dosages for nutrition and health.

  20. Atlas Based Kinematic Optimum Design of the Stewart Parallel Manipulator

    Institute of Scientific and Technical Information of China (English)

    SHAO Zhufeng; TANG Xiaoqiang; WANG Liping; SUN Dengfeng

    2015-01-01

    Optimum design is a key approach to make full use of potential advantages of a parallel manipulator. The optimum design of multi-parameter parallel manipulators(more than three design parameters), such as Stewart manipulator, relies on analysis based and algorithm based optimum design methods, which fall to be accurate or intuitive. To solve this problem and achieve both accurate and intuition, atlas based optimum design of a general Stewart parallel manipulator is established, with rational selection of design parameters. Based on the defined spherical usable workspace(SUW), primary kinematic performance indices of the Stewart manipulator, involving workspace and condition number are introduced and analyzed. Then, corresponding performance atlases are drawn with the established non-dimensional design space, and impact of joint distribution angles on the manipulator performance is analyzed and illustrated. At last, an example on atlas based optimum design of the Stewart manipulator is accomplished to illustrate the optimum design process, considering the end-effector posture. Deduced atlases can be flexibly applied to both quantitative and qualitative analysis to get the desired optimal design for the Stewart manipulator with respect to related performance requirements. Besides, the established optimum design method can be further applied to other multi-parameter parallel manipulators.

  1. Suppression of HIV replication in vitro by CpG and CpG conjugated to the non toxic B subunit of cholera toxin.

    Science.gov (United States)

    Nowroozalizadeh, Salma; Jansson, Marianne; Adamsson, Jenni; Lindblad, Marianne; Fenyö, Eva-Maria; Holmgren, Jan; Harandi, Ali M

    2008-05-01

    Administration of oligodeoxynucleotides (ODNs) containing CpG motifs generates a rapid and potent response of CC-chemokines, known as ligands of the HIV-1 co-receptor CCR5, in the murine female genital tract. The present study explored the potential HIV inhibitory activities of different human CpG prototypes either alone or conjugated to the non-toxic subunit of cholera toxin (CTB). Results showed that in vitro replication of both HIV-1 and HIV-2 can be suppressed by different human CpG prototypes. Importantly, the conjugation of CpG ODN to CTB (CTB-CpG) enhanced the antiviral activity of CpG against primary HIV-1 isolates of both R5 and X4 phenotypes in peripheral blood mononuclear cells (PBMC) as well as U87.CD4 co-receptor indicator cells. CTB-CpGs triggered higher amounts of MIP-1alpha, and MIP-1beta in PBMC than the corresponding CpG ODNs, which may explain the superior antiviral effect of CTB-CpG against R5 virus in PBMC. Incubation of PBMC with CpG ODN and CTB-CpG did not alter surface expression of HIV-1 receptors indicating that the observed anti-HIV-1 effect is not mediated through down regulation of HIV-1 receptors on target cells. Further, the enhanced antiviral effect of CTB-CpG was dependent on the presence of phosphorothioate backbone in the ODN, whereas the presence of CpG motif in ODNs was dispensable. These results have implications for the development of novel intervention strategies to prevent HIV infection.

  2. Stimulation of wild-type, F508del- and G551D-CFTR chloride channels by non toxic modified pyrrolo[2,3-b]pyrazine derivatives

    Directory of Open Access Journals (Sweden)

    Luc eDannhoffer

    2011-08-01

    Full Text Available Cystic Fibrosis is a major inherited disorder involving abnormalities of fluid and electrolyte transport in a number of different organs due to abnormal function of Cystic Fibrosis Transmembrane conductance Regulator (CFTR protein. We recently identified a family of CFTR activators, which contains the hit: RP107 [7-n-butyl-6-(4-hydroxyphenyl[5H]-pyrrolo[2,3-b]pyrazine]. Here, we further evaluated the effect of the chemical modifications of the RP107-OH radical on CFTR activation. The replacement of the OH radical by a fluorine atom at position 2 (RP193 or 4 (RP185 significantly decreased the toxicity of the compounds without altering the ability to activate CFTR, especially for RP193. The non-toxic compound RP193 has no effect on cAMP production but stimulates the channel activity of wild-type CFTR in stably transfected CHO cells, in human bronchial epithelial NuLi-1 cells and in primary culture of human bronchial epithelial cells. Whole cell and single patch clamp recordings showed that RP193 induced a linear, time and voltage-independent current, which was fully inhibited by two different and selective CFTR inhibitors (CFTRinh-172 and GPinh-5a. Moreover, RP193 stimulates CFTR in temperature-rescued CuFi-1 (F508del/F508del human bronchial epithelial cells and in CHO cells stably expressing G551D-CFTR. This study shows that it is feasible to reduce cytotoxicity of chemical compounds without affecting their potency to activate CFTR and to rescue the class 2 F508del-CFTR and class 3 G551D-CFTR CF mutant activities.

  3. Optimum blade loading for a powered rotor in descent

    Institute of Scientific and Technical Information of China (English)

    Ramin Modarres; David A. Peters

    2016-01-01

    The optimum loading for rotors has previously been found for hover, climb and wind turbine conditions;but, up to now, no one has determined the optimum rotor loading in descent. This could be an important design consideration for rotary-wing parachutes and low-speed des-cents. In this paper, the optimal loading for a powered rotor in descent is found from momentum theory based on a variational principle. This loading is compared with the optimal loading for a rotor in hover or climb and with the Betz rotor loading (which is optimum for a lightly-loaded rotor). Wake contraction for each of the various loadings is also presented.

  4. Presence detection under optimum fusion in an ultrasonic sensor system.

    Science.gov (United States)

    Srinivasan, Sriram; Pandharipande, Ashish

    2012-04-01

    Reliable presence detection is a requirement in energy-efficient occupancy-adaptive indoor lighting systems. A system of multiple ultrasonic sensors is considered for presence detection, and the performance gain from optimum fusion is studied. Two cases are considered wherein an individual sensor determines presence based on (i) local detection by processing echoes at its receiver, and (ii) the optimum Chair-Varshney fusion rule using multiple sensor detection results. The performance gains of using optimum fusion over local detection are characterized under different sensor system configurations and it is shown that improved detection sensitivity is obtained over a larger detection coverage region.

  5. DBSolve Optimum: a software package for kinetic modeling which allows dynamic visualization of simulation results

    Directory of Open Access Journals (Sweden)

    Gizzatkulov Nail M

    2010-08-01

    Full Text Available Abstract Background Systems biology research and applications require creation, validation, extensive usage of mathematical models and visualization of simulation results by end-users. Our goal is to develop novel method for visualization of simulation results and implement it in simulation software package equipped with the sophisticated mathematical and computational techniques for model development, verification and parameter fitting. Results We present mathematical simulation workbench DBSolve Optimum which is significantly improved and extended successor of well known simulation software DBSolve5. Concept of "dynamic visualization" of simulation results has been developed and implemented in DBSolve Optimum. In framework of the concept graphical objects representing metabolite concentrations and reactions change their volume and shape in accordance to simulation results. This technique is applied to visualize both kinetic response of the model and dependence of its steady state on parameter. The use of the dynamic visualization is illustrated with kinetic model of the Krebs cycle. Conclusion DBSolve Optimum is a user friendly simulation software package that enables to simplify the construction, verification, analysis and visualization of kinetic models. Dynamic visualization tool implemented in the software allows user to animate simulation results and, thereby, present them in more comprehensible mode. DBSolve Optimum and built-in dynamic visualization module is free for both academic and commercial use. It can be downloaded directly from http://www.insysbio.ru.

  6. Optimum Multiuser Detector for Multipath Slow Fading Asynchronous CDMA Channels

    Institute of Scientific and Technical Information of China (English)

    WangZhaocheng; YangZhixing; 等

    1995-01-01

    A structure of optimum multiuser detector for asynchronous CDMA in multipath slow fading channels is derived and the significant performance gain over the conventional RAKE receiv-er is shown by simulation.

  7. Optimum testing of multiple hypotheses in quantum detection theory

    Science.gov (United States)

    Yuen, H. P.; Kennedy, R. S.; Lax, M.

    1975-01-01

    The problem of specifying the optimum quantum detector in multiple hypotheses testing is considered for application to optical communications. The quantum digital detection problem is formulated as a linear programming problem on an infinite-dimensional space. A necessary and sufficient condition is derived by the application of a general duality theorem specifying the optimum detector in terms of a set of linear operator equations and inequalities. Existence of the optimum quantum detector is also established. The optimality of commuting detection operators is discussed in some examples. The structure and performance of the optimal receiver are derived for the quantum detection of narrow-band coherent orthogonal and simplex signals. It is shown that modal photon counting is asymptotically optimum in the limit of a large signaling alphabet and that the capacity goes to infinity in the absence of a bandwidth limitation.

  8. Optimum reliable operation of water distribution networks by ...

    African Journals Online (AJOL)

    Optimum reliable operation of water distribution networks by minimising energy cost and chlorine dosage. ... In this study, multi-objective optimisation of water distribution network performance in 3 different scenarios was ... Article Metrics.

  9. Determination of Optimum Moisture Content of Palm Nut Cracking ...

    African Journals Online (AJOL)

    USER

    optimum moisture content of nuts for high yield of whole kernels during cracking. Thirteen .... moisture were determined from the weight lost (ASAE, 1983;. Ajibola et al. .... measurement-Grains and Seeds, American Society of. Agricultural ...

  10. Determining the Optimum Font Size for Braille on Capsule Paper

    OpenAIRE

    Watanabe, Tetsuya

    2014-01-01

    Braille fonts allow us to easily make braille labels on capsule paper. For legibility, fonts should be printed at optimum sizes. To find the optimum sizes for Japanese braille fonts, we conducted an experiment in which a Japanese braille font was printed at various sizes on capsule paper and read and rated by young braille users. The results show that braille printed at 17 and 18 point sizes were read faster and evaluated higher than those printed at smaller or bigger sizes.

  11. The optimum grain size for minimizing energy losses in iron

    Energy Technology Data Exchange (ETDEWEB)

    Campos, M.F. de [Escola de Engenharia Industrial Metalurgica de Volta Redonda/Universidade Federal Fluminense Av. dos Trabalhadores 420, Vila Santa Cecilia, 27255-125, Volta Redonda, RJ (Brazil)]. E-mail: mcampos@metal.eeimvr.uff.br; Teixeira, J.C. [Instituto de Pesquisas Tecnologicas do Estado de Sao Paulo, Av. Prof. Almeida Prado 532, 05508-901, Sao Paulo, SP (Brazil); Landgraf, F.J.G. [Instituto de Pesquisas Tecnologicas do Estado de Sao Paulo, Av. Prof. Almeida Prado 532, 05508-901, Sao Paulo, SP (Brazil)]. E-mail: landgraf@ipt.br

    2006-06-15

    A model able to predict the optimum grain size for textured electrical steels used in motors or transformers is presented. The model is based on the Pry and Bean model for the anomalous losses. The validity of the model is restricted to the frequency range of 1-1000 Hz. The model predicts that the optimum grain size decreases as: resistivity decreases or frequency increases or thickness of steel sheet increases. The predictions of the model are compared with experimental results.

  12. OPTIMUM DESIGN BASED ON RELIABILITY IN STOCHASTIC STRUCTURE SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The optimum design method based on the reliability is presented to the stochastic structure systems (i. e., the sectional area, length, elastic module and strength of the structural member are random variables) under the random loads. The sensitivity expression of system reliability index and the safety margins were presented in the stochastic structure systems. The optimum vector method was given. First, the expressions of the reliability index of the safety margins with the improved first-order second-moment and the stochastic finite element method were deduced, and then the expressions of the systemic failure probability by probabilistic network evaluation technique(PNET) method were obtained. After derivation calculus, the expressions of the sensitivity analysis for the system reliability were obtained. Moreover, the optimum design with the optimum vector algorithm was undertaken. In the optimum iterative procedure, the gradient step and the optimum vector step were adopted to calculate. At the last, a numerical example was provided to illustrate that the method is efficient in the calculation, stably converges and fits the application in engineering.

  13. Immunological characterization of a non-toxic peptide conferring protection against the toxic fraction (AahG50) of the Androctonus australis hector venom.

    Science.gov (United States)

    Srairi-Abid, Najet; Kaabi, Hajer; Mlayah-Bellalouna, Saoussen; Mejri, Thouraya; Sampieri, François; El Ayeb, Mohamed

    2008-03-01

    KAaH1 and KAaH2 are non-toxic peptides, isolated from the venom of the Androctonus australis hector (Aah) scorpion. In a previous study, we showed these peptides to be the most abundant (approximately 10% each) in the toxic fraction (AahG50) of the Aah venom. KAaH1 and KAaH2 showed high sequence identities (approximately 60%) with birtoxin-like peptides, which likewise are the major peptidic components of Parabuthus transvaalicus scorpion venom. Here, we report the immunological characterization of KAaH1 and KAaH2. These peptides were found to be specifically recognized by polyclonal antibodies raised against AahII, the most toxic peptide of Aah venom, and represents the second antigenic group, including toxins from different scorpion species in the world. Moreover, KAaH1 partially inhibits AahII binding to its specific antibody, suggesting some common epitopes between these two peptides. The identification of possible key antigenic residues in KAaH1 was deduced from comparison of its 3-D model with the experimental structure of AahII. Two clusters of putative antigenically important residues were found at the exposed surface; one could be constituted of V3 and D53, the other of D10, T15 and Y16. Polyclonal antibodies raised against KAaH1 in mice were found to cross-react with both AahII and AahG50, and neutralizing 5LD(50)/ml of the toxic fraction. Mice vaccinated with KAaH1 were protected against a challenge of 2LD(50) of AahG50 fraction. All these data suggest that KAaH1 has clear advantages over the use of the whole or part of the venom. KAaH1 is not toxic and could produce sera-neutralizing scorpion toxins, not only from Aah venom, but also toxins of other venoms from Buthus, Leiurus, or Parabuthus scorpion species presenting antigenically related toxins.

  14. South Greenland Ice-Sheet Response to the Mid-Pliocene Climatic Optimum

    Science.gov (United States)

    Carlson, A. E.; Mathias, A.; Hatfield, R. G.; Winsor, K.; Stoner, J. S.

    2014-12-01

    The last time atmospheric carbon dioxide concentration approached present day levels was likely during the mid-Pliocene climate optimum 3.3-3.0 Ma. Estimates of sea level from the mid-Pliocene optimum vary widely and contain a significant component of glacial isostasy and dynamic topography, precluding a firm estimate of global ice volume. Here we present new data constraining the southern Greenland ice sheet (GIS) across the mid-Pliocene optimum from IODP Site U1307 located on the Eirik Ridge south of Greenland. Magnetic susceptibility dramatically decreases at ~3.3 Ma, recovering at ~3.05 Ma. Magnetic parameters on silt-size grains (Mrs/Ms) show this decrease likely reflects the loss of silt sourced from the Precambrian terranes of south Greenland, which would suggest the loss of the south GIS. The sand fraction reflects the degree of iceberg rafting with increases at an ~40 ka period. Planktic oxygen isotopes decrease during iceberg rafting events to values lower than the Holocene. An extended interval of low sand occurs from ~3.3 Ma to ~3.2 Ma, which suggests cessation of iceberg rafting. Planktic oxygen isotopes increase during this interval. Assuming a relatively warm climate, this increase could reflect the incursion of high 18-O subtropical waters into the Labrador Sea. The return of iceberg rafted sediments after ~3.2 Ma suggests the regrowth of the GIS with marine-terminating margins. Our new preliminary record points to a GIS collapse during the mid-Pliocene climatic optimum, but that ice-free conditions only lasted for ~100 ka before the return of a volatile ice sheet for the remainder of the mid-Pliocene climatic optimum.

  15. High-throughput method for optimum solubility screening for homogeneity and crystallization of proteins

    Science.gov (United States)

    Kim, Sung-Hou [Moraga, CA; Kim, Rosalind [Moraga, CA; Jancarik, Jamila [Walnut Creek, CA

    2012-01-31

    An optimum solubility screen in which a panel of buffers and many additives are provided in order to obtain the most homogeneous and monodisperse protein condition for protein crystallization. The present methods are useful for proteins that aggregate and cannot be concentrated prior to setting up crystallization screens. A high-throughput method using the hanging-drop method and vapor diffusion equilibrium and a panel of twenty-four buffers is further provided. Using the present methods, 14 poorly behaving proteins have been screened, resulting in 11 of the proteins having highly improved dynamic light scattering results allowing concentration of the proteins, and 9 were crystallized.

  16. Least cost cusp concentrator design

    Energy Technology Data Exchange (ETDEWEB)

    Nanda, S.K.; Mullick, S.C.; Annamalai, M.; Iyer, M.V.; Nirmala, K.A.; Venkatesh, P.; Prasad, C.R.; Subramani, C.

    1982-01-01

    Cusp concentrators require larger reflector areas, but can be designed for larger acceptance angles, allowing large mirror tolerances. Design procedures are outlined to compute the optimum combination of acceptance angle and maximum mirror slope for any required concentration ratio, taking into account the material as well as fabrication costs. The cusps are compared with the parabola.

  17. Umbelliprenin is Potentially Toxic Against the HT29, CT26, MCF-7, 4T1, A172, and GL26 Cell Lines, Potentially Harmful Against Bone Marrow-Derived Stem Cells, and Non-Toxic Against Peripheral Blood Mononuclear Cells

    Science.gov (United States)

    Rashidi, Mohsen; Ziai, Seyed Ali; Moini Zanjani, Taraneh; Khalilnezhad, Ahad; Jamshidi, Hamidreza; Amani, Davar

    2016-01-01

    concentrations of umbelliprenin (IC50s ranging from 713.5 ± 499.1 to 6651 ± 3670.7 µg/mL). Conclusions Our findings indicate that umbelliprenin exhibits concentration-dependent inhibitory effects on various cell types; it is potentially toxic against the HT29, CT26, MCF-7, 4T1, A172, and GL26 cell lines, potentially harmful against BMDSCs, and non-toxic against PBMCs. Therefore, if our results are approved in the future, umbelliprenin can be an appropriate candidate for developing treatments against different cancers. PMID:27703798

  18. Optimum injection dose rate of hydrogen sulfide scavenger for treatment of petroleum crude oil

    Directory of Open Access Journals (Sweden)

    T.M. Elshiekh

    2016-03-01

    Full Text Available Hydrogen sulfide H2S scavengers are chemicals that favorably react with hydrogen sulfide gas to eliminate it and produce environmental friendly products. These products depend on the type and composition of the scavenger and the conditions at which the reaction takes place. The scavenger should be widely available and economical for industry acceptance by having a low unit cost. The optimum values of H2S scavenger injection dose rate of scavenging hydrogen sulfide from the multiphase fluid produced at different wells conditions in one of the Petroleum Companies in Egypt were studied. The optimum values of H2S scavenger injection dose rate depend on pipe diameter, pipe length, gas molar mass velocity, inlet H2S concentration and pressure. The optimization results are obtained for different values of these parameters using the software program Lingo. In general, the optimum values of H2S scavenger injection dose rate of the scavenging of hydrogen sulfide are increased by increasing of the pipe diameter and increasing the inlet H2S concentration, and decreased by increasing the pipe length, gas molar mass velocity and pressure.

  19. Optimum speech level to minimize listening difficulty in public spaces.

    Science.gov (United States)

    Kobayashi, Masaaki; Morimoto, Masayuki; Sato, Hiroshi; Sato, Hayato

    2007-01-01

    For ideal speech communication in public spaces, it is important to determine the optimum speech level for various background noise levels. However, speech intelligibility scores, which is conventionally used as the subjective listening test to measure the quality of speech communication, is near perfect in most everyday situations. For this reason, it is proposed to determine optimum speech levels for speech communication in public spaces by using listening difficulty ratings. Two kinds of listening test were carried out in this work. The results of the tests and our previous work [M. Morimoto, H. Sato, and M. Kobayashi, J. Acoust. Soc. Am. 116, 1607-1613 (2004)] are jointly discussed for suggesting the relation between the optimum speech level and background noise level. The results demonstrate that: (1) optimum speech level is constant when background noise level is lower than 40 dBA, (2) optimum speech level appears to be the level, which maintains around 15 dBA of SN ratio when the background noise level is more than 40 dBA, and (3) listening difficulty increases as speech level increases under the condition where SN ratio is good enough to keep intelligibility near perfect.

  20. Parametric Investigation of Optimum Thermal Insulation Thickness for External Walls

    Directory of Open Access Journals (Sweden)

    Omer Kaynakli

    2011-06-01

    Full Text Available Numerous studies have estimated the optimum thickness of thermal insulation materials used in building walls for different climate conditions. The economic parameters (inflation rate, discount rate, lifetime and energy costs, the heating/cooling loads of the building, the wall structure and the properties of the insulation material all affect the optimum insulation thickness. This study focused on the investigation of these parameters that affect the optimum thermal insulation thickness for building walls. To determine the optimum thickness and payback period, an economic model based on life-cycle cost analysis was used. As a result, the optimum thermal insulation thickness increased with increasing the heating and cooling energy requirements, the lifetime of the building, the inflation rate, energy costs and thermal conductivity of insulation. However, the thickness decreased with increasing the discount rate, the insulation material cost, the total wall resistance, the coefficient of performance (COP of the cooling system and the solar radiation incident on a wall. In addition, the effects of these parameters on the total life-cycle cost, payback periods and energy savings were also investigated.

  1. Optimum orientation versus orientation averaging description of cluster radioactivity

    CERN Document Server

    Seif, W M; Refaie, A I; Amer, L H

    2016-01-01

    Background: The deformation of the nuclei involved in the cluster decay of heavy nuclei affect seriously their half-lives against the decay. Purpose: We investigate the description of the different decay stages in both the optimum orientation and the orientation-averaged pictures of the cluster decay process. Method: We consider the decays of 232,233,234U and 236,238Pu isotopes. The quantum mechanical knocking frequency and penetration probability based on the Wentzel-Kramers-Brillouin approximation are used to find the decay width. Results: We found that the orientation-averaged decay width is one or two orders of magnitude less than its value along the non-compact optimum orientation. The difference between the two values increases with decreasing the mass number of the emitted cluster. Correspondingly, the extracted preformation probability based on the averaged decay width increases with the same orders of magnitude compared to its value obtained considering the optimum orientation. The cluster preformati...

  2. Optimum Arrangement of Reactive Power Sources While Using Genetic Algori

    Directory of Open Access Journals (Sweden)

    A. M. Hashimov

    2010-01-01

    Full Text Available Reduction of total losses in distribution electricity supply network is considered as an important measure which serves for improvement of efficiency of electric power supply systems. This objective can be achieved by optimum distribution of reactive power sources in proper places of distribution electricity supply network. The proposed methodology is based on application of a genetic algorithm. Total expenses for installation of capacitor banks, their operation and also expenses related to electric power losses are considered as an efficiency function which is used for determination of places with optimum values of capacitor bank power. The methodology is the most efficient for selection of optimum places in the network where it is necessary to install capacitor banks with due account of their power control depending on a switched-on load value in the units.

  3. A class of optimum digital phase locked loops

    Science.gov (United States)

    Kumar, R.; Hurd, W. J.

    1986-01-01

    This paper presents a class of optimum digital filters for digital phase locked loops, for the important case in which the maximum update rate of the loop filter and numerically controlled oscillator (NCO) is limited. This case is typical when the loop filter is implemented in a microprocessor. In these situations, pure delay is encountered in the loop transfer function and thus the stability and gain margin of the loop are of crucial interest. The optimum filters designed for such situations are evaluated in terms of their gain margin for stability, dynamic error, and steady-state error performance. For situations involving considerably high phase dynamics an adaptive and programmable implementation is also proposed to obtain an overall optimum strategy.

  4. Tool Geometry for Friction Stir Welding—Optimum Shoulder Diameter

    Science.gov (United States)

    Mehta, M.; Arora, A.; de, A.; Debroy, T.

    2011-09-01

    The most important geometric parameter in the friction stir welding (FSW) tool design is the shoulder diameter, which is currently estimated by trial and error. Here, we report a combined experimental and theoretical investigation on the influence of shoulder diameter on thermal cycles, peak temperatures, power requirements, and torque during FSW of AA7075-T6. An optimum tool shoulder diameter is identified using a three-dimensional, heat transfer and materials flow model. First, the predictive capability of the model is tested by comparing the computed values of peak temperature, spindle power, and torque requirements for various shoulder diameters against the corresponding experimental data. The change in the values of these variables with shoulder diameter is correctly predicted by the model. The model is then used to identify the optimum tool shoulder diameter that facilitates maximal use of the supplied torque in overcoming interfacial sticking. The tool with optimum shoulder diameter is shown to result in acceptable yield strength (YS) and ductility.

  5. Error Exponents of Optimum Decoding for the Interference Channel

    CERN Document Server

    Etkin, Raul; Ordentlich, Erik

    2008-01-01

    Exponential error bounds for the finite-alphabet interference channel (IFC) with two transmitter-receiver pairs, are investigated under the random coding regime. Our focus is on optimum decoding, as opposed to heuristic decoding rules that have been used in previous works, like joint typicality decoding, decoding based on interference cancellation, and decoding that considers the interference as additional noise. Indeed, the fact that the actual interfering signal is a codeword and not an i.i.d. noise process complicates the application of conventional techniques to the performance analysis of the optimum decoder. Using analytical tools rooted in statistical physics, we derive a single letter expression for error exponents achievable under optimum decoding and demonstrate strict improvement over error exponents obtainable using suboptimal decoding rules, but which are amenable to more conventional analysis.

  6. Optimum climb and descent trajectories for airline missions

    Science.gov (United States)

    Erzberger, H.

    1981-01-01

    The characteristics of optimum fixed-range trajectories whose structure is constrained to climb, steady cruise, and descent segments are derived by application of optimal control theory. The performance function consists of the sum of fuel and time costs, referred to as direct operating cost (DOC). The state variable is range to go and the independent variable is energy. In this formulation a cruise segment always occurs at the optimum cruise energy for sufficiently large range. At short ranges (400 n. mi. and less), a cruise segment may also occur below the optimum cruise energy. The existence of such a cruise segment depends primarily on the fuel flow vs thrust characteristics and on thrust constraints. If thrust is a free control variable along with airspeed, it is shown that such cruise segments will not generally occur. If thrust is constrained to some maximum value in climb and to some minimum in descent, such cruise segments generally will occur.

  7. Biomass and leaf-level gas exchange characteristics of three African savanna C4 grass species under optimum growth conditions

    NARCIS (Netherlands)

    Mantlana, K.B.; Veenendaal, E.M.; Arneth, A.; Grispen, V.; Bonyongo, C.M.; Heitkönig, I.M.A.; Lloyd, J.

    2009-01-01

    C4 savanna grass species, Digitaria eriantha, Eragrostis lehmanniana and Panicum repens, were grown under optimum growth conditions with the aim of characterizing their above- and below-ground biomass allocation and the response of their gas exchange to changes in light intensity, CO2 concentration

  8. Hydrofoils: optimum lift-off speed for sailboats.

    Science.gov (United States)

    Baker, R M

    1968-12-13

    For a hydrofoil sailboat there is a unique optimum lift-off speed. Before this speed is reached, if there are no parasitic vertical hydrofoil appendages, the submerged or partially submerged hydrofoils increase drag and degrade performance. As soon as this speed is reached and the hydrofoils are fully and promptly deployed, the performance of a hydrofoil-borne craft is significantly improved. At speeds exceeding optimum lift-off speed, partially submerged hydrofoils impair performance if there is no significant effect of loading on the hydrofoil lift-to-drag ratio.

  9. Generic Advertising Optimum Budget for Iran’s Milk Industry

    Directory of Open Access Journals (Sweden)

    H. Shahbazi

    2016-05-01

    Full Text Available Introduction One of the main targets of planners, decision makers and governments is increasing society health with promotion and production of suitable and healthy food. One of the basic commodities that have important role in satisfaction of required human food is milk. So, some part of government and producer healthy budget allocate to milk consumption promotion by using generic advertising. If effectiveness of advertising budget on profitability is more, producer will have more willing to spend for advertising. Determination of optimal generic advertising budget is one of important problem in managerial decision making in producing firm as well as increase in consumption and profit and decrease in wasting and non-optimality of budget. Materials and Methods: In this study, optimal generic advertising budget intensity index (advertising budget share of production cost was estimated under two different scenarios by using equilibrium replacement model. In equilibrium replacement model, producer surplus are maximized in respect to generic advertising in retail level. According to market where two levels of farm and processing before retail exist and there is trade in farm and retail level, we present different models. Fixed and variable proportion hypothesis is another one. Finally, eight relations are presented for determination of milk generic advertising optimum budget. So, we use data from several resources such as previous studies, national (Iran Static center and international institute (Fao formal data and own estimation. Because there are several estimations in previous studies, we identify some scenarios (in two general scenarios for calculation of milk generic advertising optimum budget. Results and Discussion: Estimation of milk generic advertising optimum budget in scenario 1 shows that in case of one market level, fixed supplies and no trade, optimum budget is 0.4672539 percent. In case of one market level and no trade, optimum

  10. Aerodynamic Optimum Design of Transonic Turbine Cascades Using Genetic Algorithms

    Institute of Scientific and Technical Information of China (English)

    1997-01-01

    This paper presents an aerodynamic optimum design method for transonic turbine cascades based on the Genetic Algorithms coupled to the inviscid flow Euler Solver and the boundary-layer calculation.The Genetic Algorithms control the evolution of a population of cascades towards an optimum design.The fitness value of each string is evaluated using the flow solver.The design procedure has been developed and the behavior of the genetic algorithms has been tested.The objective functions of the design examples are the minimum mean-square deviation between the aimed pressure and computed pressure and the minimum amount of user expertise.

  11. The research on the optimum working conditions of photoconductive antenna

    Science.gov (United States)

    Shi, Wei; Dai, Yang; Zhang, Like; Yang, Lei; Yan, Zhijin; Chen, Suguo; Hou, Lei

    2015-11-01

    The photoconductive antenna (PCA) is one of the most common devices to generate terahertz (THz) wave, whose radiation efficiency is largely determined by the working conditions. In order to improve the power of THz wave, the influence of pump laser and bias voltage on the intensity of the THz wave radiated by PCA was studied through experiment and the optimum working conditions of PCA was obtained through the theoretical analysis, these are the maximum safe voltage and saturated laser energy. Only under the optimum conditions can the signal-to-noise ratio(SNR)of THz wave radiated by PCA be the highest and the PCA would not breakdown.

  12. Study on the optimum parameters for laser-solid interaction

    Institute of Scientific and Technical Information of China (English)

    Liyun Lin(林丽云); Shengbo Wang(王声波); Dahao Guo(郭大浩); Hongxing Wu(吴鸿兴); Xiaoping Xia(夏小平); Yusheng Dai(戴宇生)

    2003-01-01

    The optimum parameters for laser propulsion are discussed, such as laser induced pressure on targets,interaction parameters (Cm, Isp) and optimum laser intensity Is, etc. It is verified that the larger laserpower density will induce higher thrusting force. It is also found that, to drive a 1.010-kg target duringconfined laser ablation in vacuum and a 17.45-g one during direct laser ablation in air at the standardpressure, the needed minimum power intensities are on the same order of magnitude.

  13. Optimum high temperature strength of two-dimensional nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Monclús, M. A.; Molina-Aldareguía, J. M., E-mail: jon.molina@imdea.org [IMDEA Materials Institute, C/Eric Kandel 2, 28906 Getafe, Madrid (Spain); Zheng, S. J.; Mayeur, J. R.; Beyerlein, I. J.; Mara, N. A. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Polcar, T. [Czech Technical University in Prague, Technická 2, Prague 6 (Czech Republic); Llorca, J. [IMDEA Materials Institute, C/Eric Kandel 2, 28906 Getafe, Madrid (Spain); Department of Materials Science, Polytechnic University of Madrid, E. T. S. de Ingenieros de Caminos, 28040 Madrid (Spain)

    2013-11-01

    High-temperature nanoindentation was used to reveal nano-layer size effects on the hardness of two-dimensional metallic nanocomposites. We report the existence of a critical layer thickness at which strength achieves optimal thermal stability. Transmission electron microscopy and theoretical bicrystal calculations show that this optimum arises due to a transition from thermally activated glide within the layers to dislocation transmission across the layers. We demonstrate experimentally that the atomic-scale properties of the interfaces profoundly affect this critical transition. The strong implications are that interfaces can be tuned to achieve an optimum in high temperature strength in layered nanocomposite structures.

  14. Optimum high temperature strength of two-dimensional nanocomposites

    Directory of Open Access Journals (Sweden)

    M. A. Monclús

    2013-11-01

    Full Text Available High-temperature nanoindentation was used to reveal nano-layer size effects on the hardness of two-dimensional metallic nanocomposites. We report the existence of a critical layer thickness at which strength achieves optimal thermal stability. Transmission electron microscopy and theoretical bicrystal calculations show that this optimum arises due to a transition from thermally activated glide within the layers to dislocation transmission across the layers. We demonstrate experimentally that the atomic-scale properties of the interfaces profoundly affect this critical transition. The strong implications are that interfaces can be tuned to achieve an optimum in high temperature strength in layered nanocomposite structures.

  15. Theoretical calculation on CR-39 response for radon measurements and optimum diffusion chambers dimensions

    Science.gov (United States)

    Askari, H. R.; Ghandi, Kh.; Rahimi, M.; Negarestani, A.

    2008-11-01

    One method to measure radon gas concentration in the air with a long time of radiation is trace chemical etching technique. There is a direct proportion between the number of traces on solid-state nuclear track detectors (SSNTDs) and activity concentration of radon. In this paper, calibration constant for a cylindrical chamber with CR-39 detector has been measured analytically. Using this measurement, trace curves on the base of concentration for chambers with different heights and radii have been drawn. The results show that to measure radon gas concentration, the optimum chamber should have a height between 3.5 and 4 cm and a radius between 2.5 and 3.2 cm.

  16. Theoretical calculation on CR-39 response for radon measurements and optimum diffusion chambers dimensions

    Energy Technology Data Exchange (ETDEWEB)

    Askari, H.R.; Ghandi, Kh. [Department of Physics, Faculty of Science, Vali-e-Asr University, Rafsanjan 7713936417 (Iran, Islamic Republic of); Rahimi, M. [Department of Physics, Faculty of Science, Vali-e-Asr University, Rafsanjan 7713936417 (Iran, Islamic Republic of)], E-mail: rahimi_bam@yahoo.com; Negarestani, A. [International Center for Science and High Technology and Environmental Sciences, Kerman (Iran, Islamic Republic of)

    2008-11-11

    One method to measure radon gas concentration in the air with a long time of radiation is trace chemical etching technique. There is a direct proportion between the number of traces on solid-state nuclear track detectors (SSNTDs) and activity concentration of radon. In this paper, calibration constant for a cylindrical chamber with CR-39 detector has been measured analytically. Using this measurement, trace curves on the base of concentration for chambers with different heights and radii have been drawn. The results show that to measure radon gas concentration, the optimum chamber should have a height between 3.5 and 4 cm and a radius between 2.5 and 3.2 cm.

  17. Detection and qualification of optimum antibacterial and cytotoxic activities of silver-doped bioactive glasses.

    Science.gov (United States)

    Gholipourmalekabadi, Mazaher; Nezafati, Nader; Hajibaki, Leila; Mozafari, Masoud; Moztarzadeh, F; Hesaraki, Saeed; Samadikuchaksaraei, Ali

    2015-08-01

    This study aims to detect the optimum antibacterial activity of silver-doped bioactive glasses (Ag-BGs) for prevention of post-transplant infections in tissue engineering. The results have shown that the Ag-BG samples had broad-spectrum antibacterial efficacy in an Ag concentration-dependent manner. The 2% Ag-BG had the highest effect during the first 10 min to 72 h. The minimum inhibitory concentration of 2% Ag-BG was estimated to be 2 mg/ml for Escherichia coli (E. coli) and Pseudomonas aeruginosa (P. aeruginosa) and 2.66 mg/ml for Staphylococcus aureus (S. aureus). A concentration of 0.5% Ag-BG repressed growth of E. coli after 1 h, but did not have any detectable antibacterial effect for longer periods. Evaluation of the effects of prepared Ag-BG on human osteoblast cells viability showed that 1 and 2% samples changed the cell proliferation rate in masses of more than 3.33 and 2 mg/ml, respectively. Moreover, in a typical manner, the release of Ag ions from the glass structure started immediately, continued steadily and affected bacterial growth when it reached its critical concentration in the medium. This systematic study can illustrate the optimum antibacterial property of the Ag-BG samples in masses of 3.33 and 2 mg/ml for 1 and 2% Ag, respectively, for prevention of post-transplant infections.

  18. Antioxidant Activity and Thermal Stability of Oleuropein and Related Phenolic Compounds of Olive Leaf Extract after Separation and Concentration by Salting-Out-Assisted Cloud Point Extraction.

    Science.gov (United States)

    Stamatopoulos, Konstantinos; Katsoyannos, Evangelos; Chatzilazarou, Arhontoula

    2014-04-08

    A fast, clean, energy-saving, non-toxic method for the stabilization of the antioxidant activity and the improvement of the thermal stability of oleuropein and related phenolic compounds separated from olive leaf extract via salting-out-assisted cloud point extraction (CPE) was developed using Tween 80. The process was based on the decrease of the solubility of polyphenols and the lowering of the cloud point temperature of Tween 80 due to the presence of elevated amounts of sulfates (salting-out) and the separation from the bulk solution with centrifugation. The optimum conditions were chosen based on polyphenols recovery (%), phase volume ratio (Vs/Vw) and concentration factor (Fc). The maximum recovery of polyphenols was in total 95.9%; Vs/Vw was 0.075 and Fc was 15 at the following conditions: pH 2.6, ambient temperature (25 °C), 4% Tween 80 (w/v), 35% Na₂SO₄ (w/v) and a settling time of 5 min. The total recovery of oleuropein, hydroxytyrosol, luteolin-7-O-glucoside, verbascoside and apigenin-7-O-glucoside, at optimum conditions, was 99.8%, 93.0%, 87.6%, 99.3% and 100.0%, respectively. Polyphenolic compounds entrapped in the surfactant-rich phase (Vs) showed higher thermal stability (activation energy (Ea) 23.8 kJ/mol) compared to non-entrapped ones (Ea 76.5 kJ/mol). The antioxidant activity of separated polyphenols remained unaffected as determined by the 1,1-diphenyl-2-picrylhydrazyl method.

  19. Antioxidant Activity and Thermal Stability of Oleuropein and Related Phenolic Compounds of Olive Leaf Extract after Separation and Concentration by Salting-Out-Assisted Cloud Point Extraction

    Directory of Open Access Journals (Sweden)

    Konstantinos Stamatopoulos

    2014-04-01

    Full Text Available A fast, clean, energy-saving, non-toxic method for the stabilization of the antioxidant activity and the improvement of the thermal stability of oleuropein and related phenolic compounds separated from olive leaf extract via salting-out-assisted cloud point extraction (CPE was developed using Tween 80. The process was based on the decrease of the solubility of polyphenols and the lowering of the cloud point temperature of Tween 80 due to the presence of elevated amounts of sulfates (salting-out and the separation from the bulk solution with centrifugation. The optimum conditions were chosen based on polyphenols recovery (%, phase volume ratio (Vs/Vw and concentration factor (Fc. The maximum recovery of polyphenols was in total 95.9%; Vs/Vw was 0.075 and Fc was 15 at the following conditions: pH 2.6, ambient temperature (25 °C, 4% Tween 80 (w/v, 35% Na2SO4 (w/v and a settling time of 5 min. The total recovery of oleuropein, hydroxytyrosol, luteolin-7-O-glucoside, verbascoside and apigenin-7-O-glucoside, at optimum conditions, was 99.8%, 93.0%, 87.6%, 99.3% and 100.0%, respectively. Polyphenolic compounds entrapped in the surfactant-rich phase (Vs showed higher thermal stability (activation energy (Ea 23.8 kJ/mol compared to non-entrapped ones (Ea 76.5 kJ/mol. The antioxidant activity of separated polyphenols remained unaffected as determined by the 1,1-diphenyl-2-picrylhydrazyl method.

  20. Optimum Resolution in X-Ray Energy-Dispersive Diffractometry

    DEFF Research Database (Denmark)

    Buras, B.; Niimura, N.; Staun Olsen, J.

    1978-01-01

    The resolution problem in X-ray energy-dispersive diffractometry is discussed. It is shown that for a given characteristic of the solid-state detector system and a given range of interplanar spacings, an optimum scattering angle can be easily found for any divergence of the incident and scattered...

  1. Optimum Onager: The Classical Mechanics of a Classical Siege Engine

    Science.gov (United States)

    Denny, Mark

    2009-01-01

    The onager is a throwing weapon of classical antiquity, familiar to both the ancient Greeks and Romans. Here we analyze the dynamics of onager operation and derive the optimum angle for launching a projectile to its maximum range. There is plenty of scope for further considerations about increasing onager range, and so by thinking about how this…

  2. An Optimum Scheme to Generate Entangled Photon Pairs

    Institute of Scientific and Technical Information of China (English)

    GAO Xiang; WANG Xiao-Lu; LI Jia-Ming

    2007-01-01

    An optimum scheme is proposed to generate a strong entangled photon-pair light source by combining two incident laser lights. Such entangled photon source should have various potential applications in many fields such as quantum metrology, quantum information, and quantum lithography, etc.

  3. Site survey for optimum location of Optical Communication Experimental Facility

    Science.gov (United States)

    1968-01-01

    Site survey was made to determine the optimum location for an Optical Communication Experimental Facility /OCEF/ and to recommend several sites, graded according to preference. A site was desired which could perform two-way laser communication with a spacecraft and laser tracking with a minimum of interruption by weather effects.

  4. Applicability Problem in Optimum Reinforced Concrete Structures Design

    Directory of Open Access Journals (Sweden)

    Ashara Assedeq

    2016-01-01

    Full Text Available Optimum reinforced concrete structures design is very complex problem, not only considering exactness of calculus but also because of questionable applicability of existing methods in practice. This paper presents the main theoretical mathematical and physical features of the problem formulation as well as the review and analysis of existing methods and solutions considering their exactness and applicability.

  5. How stem defects affect the capability of optimum bucking method?

    Directory of Open Access Journals (Sweden)

    Abdullah Emin Akay

    2015-07-01

    Full Text Available In forest harvesting activities, computer-assisted optimum bucking method increases the economic value of harvested trees. The bucking decision highly depends on the log quality grades which mainly vary with the surface characteristics such as stem defects and form of the stems. In this study, the effects of stem defects on optimum bucking method was investigated by comparing bucking applications which were conducted during the logging operations in two different Brutian Pine (Pinus brutia Ten stands. In the applications, the first stand contained the stems with relatively more stem defects than that of the stems in the second stand. The average number of defects per log for sample trees in the first and the second stand was recorded as 3.64 and 2.70, respectively. The results indicated that optimum bucking method increased the average economic value of harvested trees by 15.45% and 8.26 % in the stands, respectively. Therefore, the computer-assisted optimum bucking method potentially provides better results than that of traditional bucking method especially for the harvested trees with more stem defects.

  6. Noncommutative QED Threshold Energy versus Optimum Collision Energy

    Institute of Scientific and Technical Information of China (English)

    SHENG Zheng-Mao; FU Yong-Ming; YU Hai-Bo

    2005-01-01

    @@ M(o)11er scattering and Bhabha scattering on noncommutative (NC) space-time is restudied. It is shown that the NC correction of scattering sections is not monotonic enhancement with total energy of colliding electrons, that there is an optimum collision energy to perform the greatest NC correction.

  7. Optimum design of Nd-doped fiber optical amplifiers

    DEFF Research Database (Denmark)

    Rasmussen, Thomas; Bjarklev, Anders Overgaard; Lumholt, Ole

    1992-01-01

    The waveguide parameters for a Nd-doped fluoride (Nd:ZBLANP) fiber amplifier have been optimized for small-signal and booster operation using an accurate numerical model. The optimum cutoff wavelength is shown to be 800 nm and the numerical aperture should be made as large as possible. Around 80...

  8. Optimum Location of Tube Blank in Electromagnetic Bulging

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Using analytical method, this paper gets the mutual inductance between coil and workpiece in tube blank electromagnetic bulging. According to this, we obtain the optimum locations of tube blank with different length of coil and workpiece. There is a good agreement between results calculated and the experimental data.

  9. An Application of Calculus: Optimum Parabolic Path Problem

    Science.gov (United States)

    Atasever, Merve; Pakdemirli, Mehmet; Yurtsever, Hasan Ali

    2009-01-01

    A practical and technological application of calculus problem is posed to motivate freshman students or junior high school students. A variable coefficient of friction is used in modelling air friction. The case in which the coefficient of friction is a decreasing function of altitude is considered. The optimum parabolic path for a flying object…

  10. An Application of Calculus: Optimum Parabolic Path Problem

    Science.gov (United States)

    Atasever, Merve; Pakdemirli, Mehmet; Yurtsever, Hasan Ali

    2009-01-01

    A practical and technological application of calculus problem is posed to motivate freshman students or junior high school students. A variable coefficient of friction is used in modelling air friction. The case in which the coefficient of friction is a decreasing function of altitude is considered. The optimum parabolic path for a flying object…

  11. Nutritional requirements of the BY series of Saccharomyces cerevisiae strains for optimum growth.

    Science.gov (United States)

    Hanscho, Michael; Ruckerbauer, David E; Chauhan, Neha; Hofbauer, Harald F; Krahulec, Stefan; Nidetzky, Bernd; Kohlwein, Sepp D; Zanghellini, Juergen; Natter, Klaus

    2012-11-01

    Among the vast variety of Saccharomyces cerevisiae strains, the BY family is particularly important because the widely used deletion collections are based on this background. Here we demonstrate that some standard growth media recipes require substantial modifications to provide optimum growth conditions for auxotrophic BY strains and to avoid growth arrest before glucose is depleted. In addition to the essential supplements that are required to satisfy auxotrophic requirements, we found the four amino acids phenylalanine, glutamic acid, serine, and threonine to be indispensable for optimum growth, despite the fact that BY is 'prototrophic' for these amino acids. Interestingly, other widely used S. cerevisiae strains, such as strains of the CEN.PK family, are less sensitive to lack of the described supplements. Furthermore, we found that the concentration of inositol in yeast nitrogen base is too low to support fast proliferation of yeast cultures until glucose is exhausted. Depletion of inositol during exponential growth induces characteristic changes, namely a decrease in glucose uptake and maximum specific growth rate, increased cell size, reduced viability, and accumulation of lipid storage pools. Thus, several of the existing growth media recipes need to be revised to achieve optimum growth conditions for BY-derived strains. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  12. Optimum primary and supplementary signals optimizing the seismic data resolution

    Science.gov (United States)

    Tyapkin, Yuriy K.

    2001-03-01

    Often in practice, when generating seismic waves on a line, even with a wide-band source, numerous natural and technical obstacles cause a low resolution of reflection seismograms. In this case, the economy of the survey should be taken into consideration and rather than ignoring preexisting data, generating additional signal to complement the preexisting data should be tried. This paper describes how this can be done to optimize the resolution of the combined data. The new approach requires a fundamental change in the field technique such that records with different spectral characteristics (RDSC) are now generated from each source-receiver pair. These coincident records share a common reflectivity series, but differ from each other in wavelets and noise. A comprehensive theory for optimum processing (deconvolution) of any available suite of the RDSC is developed. The solution for the problem is a particular case of multichannel Wiener filtering. It can be thought of as two successive procedures. The first is optimum frequency-dependent weighted stacking of the RDSC. The second is single-channel zero-phase Wiener deconvolution filtering of the previous output. This representation enables suggested multichannel filtering to be easily implemented. The effectiveness of the method as well as its advantage over straight summing of the RDSC, followed by single-channel Wiener deconvolution filtering, are corroborated theoretically and demonstrated with field data. Furthermore, a solution is suggested for the problem to evaluate the spectrum of an optimum supplementary signal. The signal contributes to the available set of the RDSC and yields either maximum resolution with limited energy expenses or a certain desired resolution with minimum, but unrestricted energy expenses at the output of the optimum procedure. The optimum distribution of the spectral energy of a primary signal along the frequency axis is a particular case of the above problem with no preexisting data.

  13. Early photosensitizer uptake kinetics predict optimum drug-light interval for photodynamic therapy

    Science.gov (United States)

    Sinha, Lagnojita; Elliott, Jonathan T.; Hasan, Tayyaba; Pogue, Brian W.; Samkoe, Kimberley S.; Tichauer, Kenneth M.

    2015-03-01

    Photodynamic therapy (PDT) has shown promising results in targeted treatment of cancerous cells by developing localized toxicity with the help of light induced generation of reactive molecular species. The efficiency of this therapy depends on the product of the intensity of light dose and the concentration of photosensitizer (PS) in the region of interest (ROI). On account of this, the dynamic and variable nature of PS delivery and retention depends on many physiological factors that are known to be heterogeneous within and amongst tumors (e.g., blood flow, blood volume, vascular permeability, and lymph drainage rate). This presents a major challenge with respect to how the optimal time and interval of light delivery is chosen, which ideally would be when the concentration of PS molecule is at its maximum in the ROI. In this paper, a predictive algorithm is developed that takes into consideration the variability and dynamic nature of PS distribution in the body on a region-by-region basis and provides an estimate of the optimum time when the PS concentration will be maximum in the ROI. The advantage of the algorithm lies in the fact that it predicts the time in advance as it takes only a sample of initial data points (~12 min) as input. The optimum time calculated using the algorithm estimated a maximum dose that was only 0.58 +/- 1.92% under the true maximum dose compared to a mean dose error of 39.85 +/- 6.45% if a 1 h optimal light deliver time was assumed for patients with different efflux rate constants of the PS, assuming they have the same plasma function. Therefore, if the uptake values of PS for the blood and the ROI is known for only first 12 minutes, the entire curve along with the optimum time of light radiation can be predicted with the help of this algorithm.

  14. The effect of crumb rubber particle size to the optimum binder content for open graded friction course.

    Science.gov (United States)

    Ibrahim, Mohd Rasdan; Katman, Herda Yati; Karim, Mohamed Rehan; Koting, Suhana; Mashaan, Nuha S

    2014-01-01

    The main objective of this paper is to investigate the relations of rubber size, rubber content, and binder content in determination of optimum binder content for open graded friction course (OGFC). Mix gradation type B as specified in Specification for Porous Asphalt produced by the Road Engineering Association of Malaysia (REAM) was used in this study. Marshall specimens were prepared with four different sizes of rubber, namely, 20 mesh size [0.841 mm], 40 mesh [0.42 mm], 80 mesh [0.177 mm], and 100 mesh [0.149 mm] with different concentrations of rubberised bitumen (4%, 8%, and 12%) and different percentages of binder content (4%-7%). The appropriate optimum binder content is then selected according to the results of the air voids, binder draindown, and abrasion loss test. Test results found that crumb rubber particle size can affect the optimum binder content for OGFC.

  15. Effect of fly ash on the optimum sulfate of Portland Cement

    Science.gov (United States)

    Niemuth, Mark D.

    testing of the theories is done by characterization through isothermal calorimetry, semi-quantitative x-ray diffraction (XRD), and pore solution ion concentration. This provides data that can be used to evaluate the explanations of why some fly ashes influence optimum sulfate. The fly ash C3A and SO3 have strong correlations to the increase in optimum sulfate along with freelime and soluble alkalis. The effect of the fly ash C3A can be explained by the reactions that occur with sulfate to form ettringite or monosulfate, by the reaction with sulfate to form ettringite which contributes to strength at higher levels, or by retardation of the main alite hydration peak of the cement which requires additional sulfate to keep the sulfate depletion after the main alite hydration peak. The position of the sulfate depletion peak relative the main alite hydration peak has been correlated to optimum sulfate in the past and in this thesis.

  16. A new optimum topology switching dc-to-dc converter

    Science.gov (United States)

    Cuk, S.; Middlebrook, R. D.

    1977-01-01

    A novel switching dc-to-dc converter is presented, which has the same general conversion property (increase or decrease of the input dc voltage) as does the conventional buck-boost converter, and which offers through its new optimum topology higher efficiency, lower output voltage ripple, reduced EMI, smaller size and weight, and excellent dynamic response. One of its most significant advantages is that both input and output current are not pulsating but are continuous (essentially dc with small superimposed switching current ripple), thus resulting in a close approximation to the ideal physically nonrealizable dc-to-dc transformer. The converter retains the simplest possible structure with the minimum number of components which, when interconnected in its optimum topology, yield the maximum performance.

  17. A methodology for selecting optimum organizations for space communities

    Science.gov (United States)

    Ragusa, J. M.

    1978-01-01

    This paper suggests that a methodology exists for selecting optimum organizations for future space communities of various sizes and purposes. Results of an exploratory study to identify an optimum hypothetical organizational structure for a large earth-orbiting multidisciplinary research and applications (R&A) Space Base manned by a mixed crew of technologists are presented. Since such a facility does not presently exist, in situ empirical testing was not possible. Study activity was, therefore, concerned with the identification of a desired organizational structural model rather than the empirical testing of it. The principal finding of this research was that a four-level project type 'total matrix' model will optimize the effectiveness of Space Base technologists. An overall conclusion which can be reached from the research is that application of this methodology, or portions of it, may provide planning insights for the formal organizations which will be needed during the Space Industrialization Age.

  18. Determination of optimum pressurizer level for kori unit 1

    Energy Technology Data Exchange (ETDEWEB)

    Song, Dong Soo; Lee, Chang Sup; Lee Jae Yong; Kim, Yo Han; Lee, Dong Hyuk [Korea Electric Power Research Institute, Taejon (Korea, Republic of)

    1997-12-31

    To determine the optimum pressurizer water level during normal operation for Kori unit 1, performance and safety analysis are performed. The methodology is developed by evaluating {sup d}ecrease in secondary heat removal{sup e}vents such as Loss of Normal Feedwater accident. To demonstrate optimum pressurizer level setpoint, RETRAN-03 code is used for performance analysis. Analysis results of RETRAN following reactor trip are compared with the actual plant data to justify RETRAN code modelling. The results of performance and safety analyses show that the newly established level setpoints not only improve the performance of pressurizer during transient including reactor trip but also meet the design bases of the pressurizer volume and pressure. 6 refs., 5 figs. (Author)

  19. Rough Set Fuzzy Optimum Selecting in Multidisciplinary System

    Institute of Scientific and Technical Information of China (English)

    LIU Xu-lin; SONG Bao-wei; WANG Jin-hua; CHEN Jie

    2008-01-01

    Scheme evaluation and selection is an optimum selecting and sequencing problem with multi-objective and multi- level. It can't follow single objective function or rule. Meanwhile, these objectives are coupled with each other and the at- tribution information is fuzzy also. It is necessary to find an effective evaluation method which can consider all conditions and restrictions. In this paper, AHP and rough set theory are applied to fuzzy optimization to determine important weight of each attribution. The rough set fuzzy optimum selection is used to eliminate the useless information. Autonomous un- derwater vehicle (AUV) is large-scah systems with many coupled design variables and objective functions. Their scheme evaluation and selection are very important, which relate to multiple factors, such as reliability;security, service time; the lifeeyele, etc. Results of application in torpedo design indicate that this method is feasible.

  20. Fisher information as a performance metric for locally optimum processing

    CERN Document Server

    Duan, Fabing; Abbott, Derek

    2011-01-01

    For a known weak signal in additive white noise, the asymptotic performance of a locally optimum processor (LOP) is shown to be given by the Fisher information (FI) of a standardized even probability density function (PDF) of noise in three cases: (i) the maximum signal-to-noise ratio (SNR) gain for a periodic signal; (ii) the optimal asymptotic relative efficiency (ARE) for signal detection; (iii) the best cross-correlation gain (CG) for signal transmission. The minimal FI is unity, corresponding to a Gaussian PDF, whereas the FI is certainly larger than unity for any non-Gaussian PDFs. In the sense of a realizable LOP, it is found that the dichotomous noise PDF possesses an infinite FI for known weak signals perfectly processed by the corresponding LOP. The significance of FI lies in that it provides a upper bound for the performance of locally optimum processing.

  1. Optimum Disposition of Metal Particles in the Propellant Grain

    Directory of Open Access Journals (Sweden)

    Leonid L. Minkov

    2014-01-01

    Full Text Available Using the dispersed metal in solid propellants to increase the temperature of combustion products leads to such a problem as the specific impulse loss due to the incomplete combustion of metal particles in the exhaust products. A redistribution of metal loaded into the propellant grain is one of the methods to decrease the specific impulse loss. This paper reports on the ways to obtain the optimum metal particle disposition for the case-bounded propellant grain of tube cross-sectional type. Three different approaches to analyze the metal combustion efficiency are discussed. The influence of the dynamic nonequilibrium of two-phase flow on the optimum metal particles disposition in the propellant grain of tube cross-sectional type is investigated.

  2. Traffic Network Optimum Principle - Minimum Probability of Congestion Occurrence

    CERN Document Server

    Kerner, Boris S

    2010-01-01

    We introduce an optimum principle for a vehicular traffic network with road bottlenecks. This network breakdown minimization (BM) principle states that the network optimum is reached, when link flow rates are assigned in the network in such a way that the probability for spontaneous occurrence of traffic breakdown at one of the network bottlenecks during a given observation time reaches the minimum possible value. Based on numerical simulations with a stochastic three-phase traffic flow model, we show that in comparison to the well-known Wardrop's principles the application of the BM principle permits considerably greater network inflow rates at which no traffic breakdown occurs and, therefore, free flow remains in the whole network.

  3. Optimum design of B-series marine propellers

    Directory of Open Access Journals (Sweden)

    M.M. Gaafary

    2011-03-01

    Full Text Available The choice of an optimum marine propeller is one of the most important problems in naval architecture. This problem can be handled using the propeller series diagrams or regression polynomials. This paper introduces a procedure to find out the optimum characteristics of B-series marine propellers. The propeller design process is performed as a single objective function subjected to constraints imposed by cavitation, material strength and required propeller thrust. Although optimization software of commercial type can be adopted to solve the problem, the computer program that has been specially developed for this task may be more useful for its flexibility and possibility to be incorporated, as a subroutine, with the complex ship design process.

  4. Optimum Production Control and Workforce Scheduling of Machining Project

    Science.gov (United States)

    Lan, Tian-Syung; Lo, Chih-Yao; Hou, Cheng-I.

    Through the proposed model in this study, the production control with the consideration of workforce scheduling for advanced manufacturing systems becomes realistically and concretely solvable. This study not only meditates the concept of balancing machine productivity and human ability into the objective, but also implements Calculus of Variations to optimize the profit for a deterministic production quantity. In addition, the optimum solutions of dynamic productivity control and workforce scheduling are comprehensively provided. Moreover, the decision criteria for selecting the optimum solution and the sensitivity analysis of the critical variables are fully discussed. This study definitely contributes the applicable strategy to control the productivity and workforce in manufacturing and provides the valuable tool to conclusively optimize the profit of a machining project for operations research in today`s manufacturing industry with profound insight.

  5. Optimum Conditions for Uricase Enzyme Production by Gliomastix gueg

    Directory of Open Access Journals (Sweden)

    Atalla, M. M.

    2009-01-01

    Full Text Available Nineteen strains of microorganisms were screened for uricase production. Gliomastix gueg was recognized to produce high levels of the enzyme. The optimum fermentation conditions for uricase production by Gliomastix gueg were examined. Results showed that uric acid medium was the most favorable one, the optimum temperature was at 30ºC, and incubation period required for maximum production was 8 days with aeration level at 150 rpm and at pH 8.0. Sucrose proved to be the best carbon source, uric acid was found to be the best nitrogen source. Both, dipotassium hydrogen phosphate and ferrous chloride as well as some vitamins gave the highest amount of uricase by Gliomastix gueg.

  6. Determination of Optimum Conditions for the Production of Activated Carbon Derived from Separate Varieties of Coconut Shells

    Directory of Open Access Journals (Sweden)

    E. S. Sanni

    2017-01-01

    Full Text Available Activated carbons were produced from coconut shells of tall and dwarf tree varieties. The activated carbon from the tall tree variety was initially synthesized using 1 M concentration of each of ZnCl2, H3PO4, and KOH solutions. From the adsorptive tests conducted using methylene blue solution, the activated carbon produced with H3PO4 gave the best absorbance and adsorptive performance. Coconut shells of dwarf tree variety were then obtained and treated with same mass of coconut shells of the tall tree variety using varied concentrations of the acid in order to determine whether the optimum concentration and temperature for producing carbon black from the coconut shells are distinct or similar for both varieties. The process was also modelled using the Differential Response Method (DRM in order to determine the yields and adsorptive performances of the activated carbons by varying the carbonization temperature and concentration. The results from experiment and the developed mathematical model were both found to be in agreement giving the optimum concentration of phosphoric acid and pH for producing activated carbon to be 0.67 M and 2.07 for the tall tree variety and 1 M and 1.98 for the dwarf variety at optimum temperatures in the range of 450–575°C and 575°C, respectively.

  7. Optimum municipal wastewater treatment plant design with consideration of uncertainty

    Institute of Scientific and Technical Information of China (English)

    ZENG Guang-ming; LIN Yu-peng; QIN Xiao-sheng; HUANG Guo-he; LI Jian-bing; JIANG Ru

    2004-01-01

    A newly developed model for the optimum municipal wastewater treatment plant (MWTP) design is presented. Through introducing the interval variables, the model attempts to consider the effects of uncertainties caused by the fluctuation of the wastewater quality and quantity during the design of MWTP. The model solution procedure is illustrated in detail, and a numerical example is given to verify the feasibility and advantage of the model. Furthermore, the possibility of the model application is briefly outlined.

  8. Optimum sensitivity derivatives of objective functions in nonlinear programming

    Science.gov (United States)

    Barthelemy, J.-F. M.; Sobieszczanski-Sobieski, J.

    1983-01-01

    The feasibility of eliminating second derivatives from the input of optimum sensitivity analyses of optimization problems is demonstrated. This elimination restricts the sensitivity analysis to the first-order sensitivity derivatives of the objective function. It is also shown that when a complete first-order sensitivity analysis is performed, second-order sensitivity derivatives of the objective function are available at little additional cost. An expression is derived whose application to linear programming is presented.

  9. [Study on optimum extraction conditions of alkaloids from Pinellia ternate].

    Science.gov (United States)

    Zeng, Jianhong; Peng, Zhengsong; Mao, Zicheng; Wei, Shuhong

    2003-05-01

    The optimum extraction conditions of alkaloids from Pinellia ternate (Thunb.) Breit were studied by orthogonal test. The results showed that the highest extraction rate of the alkaloids could be obtained by smashing the material in 60 (sieve number) of fragmentation and socking the material in 2.575 mol/L ammonia water, extracting alkaloids with 18 times as much chlorolform at room temperature for 25 hours. The highest extraction rate of alkaloids was 0.0817%.

  10. Immune Algorithm for Selecting Optimum Services in Web Services Composition

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    For the problem of dynamic optimization in Web services composition, this paper presents a novel approach for selecting optimum Web services, which is based on the longest path method of weighted multistage graph. We propose and implement an Immune Algorithm for global optimization to construct composed Web services. Results of the experimentation illustrates that the algorithm in this paper has a powerful capability and can greatly improve the efficiency and veracity in service selection.

  11. Inverse design of nonlinearity in energy harvesters for optimum damping

    Science.gov (United States)

    Ghandchi Tehrani, Maryam; Elliott, S. J.

    2016-09-01

    This paper presents the inverse design method for the nonlinearity in an energy harvester in order to achieve an optimum damping. A single degree-of-freedom electromechanical oscillator is considered as an energy harvester, which is subjected to a harmonic base excitation. The harvester has a limited throw due to the physical constraint of the device, which means that the amplitude of the relative displacement between the mass of the harvester and the base cannot exceed a threshold when the device is driven at resonance and beyond a particular amplitude. This physical constraint requires the damping of the harvester to be adjusted for different excitation amplitudes, such that the relative displacement is controlled and maintained below the limit. For example, the damping can be increased to reduce the amplitude of the relative displacement. For high excitation amplitudes, the optimum damping is, therefore, dependent on the amplitude of the base excitation, and can be synthesised by a nonlinear function. In this paper, a nonlinear function in the form of a bilinear is considered to represent the damping model of the device. A numerical optimisation using Matlab is carried out to fit a curve to the amplitude-dependent damping in order to determine the optimum bilinear model. The nonlinear damping is then used in the time-domain simulations and the relative displacement and the average harvested power are obtained. It is demonstrated that the proposed nonlinear damping can maintain the relative displacement of the harvester at its maximum level for a wide range of excitation, therefore providing the optimum condition for power harvesting.

  12. An optimum analysis sequence for environmental gamma-ray spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    De la Torre, F.; Rios M, C.; Ruvalcaba A, M. G.; Mireles G, F.; Saucedo A, S.; Davila R, I.; Pinedo, J. L., E-mail: fta777@hotmail.co [Universidad Autonoma de Zacatecas, Centro Regional de Estudis Nucleares, Calle Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)

    2010-10-15

    This work aims to obtain an optimum analysis sequence for environmental gamma-ray spectroscopy by means of Genie 2000 (Canberra). Twenty different analysis sequences were customized using different peak area percentages and different algorithms for: 1) peak finding, and 2) peak area determination, and with or without the use of a library -based on evaluated nuclear data- of common gamma-ray emitters in environmental samples. The use of an optimum analysis sequence with certified nuclear information avoids the problems originated by the significant variations in out-of-date nuclear parameters of commercial software libraries. Interference-free gamma ray energies with absolute emission probabilities greater than 3.75% were included in the customized library. The gamma-ray spectroscopy system (based on a Ge Re-3522 Canberra detector) was calibrated both in energy and shape by means of the IAEA-2002 reference spectra for software intercomparison. To test the performance of the analysis sequences, the IAEA-2002 reference spectrum was used. The z-score and the reduced {chi}{sup 2} criteria were used to determine the optimum analysis sequence. The results show an appreciable variation in the peak area determinations and their corresponding uncertainties. Particularly, the combination of second derivative peak locate with simple peak area integration algorithms provides the greater accuracy. Lower accuracy comes from the combination of library directed peak locate algorithm and Genie's Gamma-M peak area determination. (Author)

  13. Optimum profit model considering production, quality and sale problem

    Science.gov (United States)

    Chen, Chung-Ho; Lu, Chih-Lun

    2011-12-01

    Chen and Liu ['Procurement Strategies in the Presence of the Spot Market-an Analytical Framework', Production Planning and Control, 18, 297-309] presented the optimum profit model between the producers and the purchasers for the supply chain system with a pure procurement policy. However, their model with a simple manufacturing cost did not consider the used cost of the customer. In this study, the modified Chen and Liu's model will be addressed for determining the optimum product and process parameters. The authors propose a modified Chen and Liu's model under the two-stage screening procedure. The surrogate variable having a high correlation with the measurable quality characteristic will be directly measured in the first stage. The measurable quality characteristic will be directly measured in the second stage when the product decision cannot be determined in the first stage. The used cost of the customer will be measured by adopting Taguchi's quadratic quality loss function. The optimum purchaser's order quantity, the producer's product price and the process quality level will be jointly determined by maximising the expected profit between them.

  14. The theory of an ‘optimum currency area’

    Directory of Open Access Journals (Sweden)

    Jarosław Kundera

    2012-12-01

    Full Text Available The main goal of this paper is to analyse and distinguish the main components of the theory of an ‘Optimum Currency Area’. The theory of an optimum currency area indicates some essential elements as preconditions for the successful introduction of a common currency: high mobility of labour, openness of the economy defined as a high proportion of tradable to non-tradable goods, and high diversification of domestic production before joining the union. The article’s analysis helps to better understanding the reasons of the current crisis in the euro zone. The main problem with a common currency area is the adjustment to imbalances, which cannot take place through exchange rates in conditions of a common currency. The missing elements of the theory are the role of the mobility of capital to correct interregional balance of payments disequilibria and lack of a common budget with sufficient own resources during the occurrence of debt crises in member countries. The theory of an optimum currency area has noticed the importance of coordination between fiscal and monetary policy and the necessity of redistribution of resources among partners. However, it does not say much about the methods applied, how to deal with debt crises and what the cost of a potential breaking up of monetary union would be.

  15. Fluidization and Optimum Backwashing Conditions in Multimedia Filter

    Directory of Open Access Journals (Sweden)

    Rusul Naseer

    2011-11-01

    Full Text Available The aim of this study is to study and evaluate the fluidization and optimum backwashing conditions which include minimum fluidization velocity, expanded bed porosity and energy dissipation under different operation conditions with different media grain size in multimedia filter. Theoretical and experimental study was performed to evaluate the backwashing process of multimedia filter by fluidizing the filter media whereas backwashing Process was carried out by a pilot laboratory filter of multimedia filter column using different characteristics of filters media. A model was built to predict the expanded bed filter and the fluidized porosity. The result showed that proposed model give a good fit with observed data. It is observed that smaller grain sand was needed a lower value of backwash rate then of the higher grain sand to rise the filter media and the fixed porosity 0.51 will expand to the optimum fluidized porosity 0.704 for a bigger value of grain sand while the smaller value of grain diameter 0.5 mm was expanded to the optimum fluidized porosity 0.68. It is also concluded that the effluent turbidity and detachment rate of deposited material decreases with increasing backwashing time and increasing total backwash rate. It is also concluded that the energy dissipation and the velocity gradient have a dominant mechanism of filter cleaning.

  16. Spatial optimum collocation model of urban land and its algorithm

    Science.gov (United States)

    Kong, Xiangqiang; Li, Xinyun

    2007-06-01

    Optimizing the allocation of urban land is that layout and fix position the various types of land-use in space, maximize the overall benefits of urban space (including economic, social, environment) using a certain method and technique. There is two problems need to deal with in optimizing the allocation of urban land in the technique: one is the quantitative structure, the other is the space structure. In allusion to these problems, according to the principle of spatial coordination, a kind of new optimum collocation model about urban land was put forward in this text. In the model, we give a target function and a set of "soft" constraint conditions, and the area proportions of various types of land-use are restricted to the corresponding allowed scope. Spatial genetic algorithm is used to manipulate and calculate the space of urban land, the optimum spatial collocation scheme can be gradually approached, in which the three basic operations of reproduction, crossover and mutation are all operated on the space. Taking the built-up areas of Jinan as an example, we did the spatial optimum collocation experiment of urban land, the spatial aggregation of various types is better, and an approving result was got.

  17. The optimum decision rules for the oddity task.

    Science.gov (United States)

    Versfeld, N J; Dai, H; Green, D M

    1996-01-01

    This paper presents the optimum decision rule for an m-interval oddity task in which m-1 intervals contain the same signal and one is different or odd. The optimum decision rule depends on the degree of correlation among observations. The present approach unifies the different strategies that occur with "roved" or "fixed" experiments (Macmillan & Creelman, 1991, p. 147). It is shown that the commonly used decision rule for an m-interval oddity task corresponds to the special case of highly correlated observations. However, as is also true for the same-different paradigm, there exists a different optimum decision rule when the observations are independent. The relation between the probability of a correct response and d' is derived for the three-interval oddity task. Tables are presented of this relation for the three-, four-, and five-interval oddity task. Finally, an experimental method is proposed that allows one to determine the decision rule used by the observer in an oddity experiment.

  18. Solid-state, ambient-operation thermally activated delayed fluorescence from flexible, non-toxic gold-nanocluster thin films: towards the development of biocompatible light-emitting devices

    Science.gov (United States)

    Talite, M. J. A.; Lin, H. T.; Jiang, Z. C.; Lin, T. N.; Huang, H. Y.; Heredia, E.; Flores, A.; Chao, Y. C.; Shen, J. L.; Lin, C. A. J.; Yuan, C. T.

    2016-08-01

    Luminescent gold nanoclusters (AuNCs) with good biocompatibility have gained much attention in bio-photonics. In addition, they also exhibit a unique photo-physical property, namely thermally activated delayed fluorescence (TADF), by which both singlet and triplet excitons can be harvested. The combination of their non-toxic material property and unique TADF behavior makes AuNCs biocompatible nano-emitters for bio-related light-emitting devices. Unfortunately, the TADF emission is quenched when colloidal AuNCs are transferred to solid states under ambient environment. Here, a facile, low-cost and effective method was used to generate efficient and stable TADF emissions from solid AuNCs under ambient environment using polyvinyl alcohol as a solid matrix. To unravel the underlying mechanism, temperature-dependent static and transient photoluminescence measurements were performed and we found that two factors are crucial for solid TADF emission: small energy splitting between singlet and triplet states and the stabilization of the triplet states. Solid TADF films were also deposited on the flexible plastic substrate with patterned structures, thus mitigating the waveguide-mode losses. In addition, we also demonstrated that warm white light can be generated based on a co-doped single emissive layer, consisting of non-toxic, solution-processed TADF AuNCs and fluorescent carbon dots under UV excitation.

  19. Physical Meaning of the Optimum Measurement Process in Quantum Detection Theory

    Science.gov (United States)

    Osaki, Masao; Kozuka, Haruhisa; Hirota, Osamu

    1996-01-01

    The optimum measurement processes are represented as the optimum detection operators in the quantum detection theory. The error probability by the optimum detection operators goes beyond the standard quantum limit automatically. However the optimum detection operators are given by pure mathematical descriptions. In order to realize a communication system overcoming the standard quantum limit, we try to give the physical meaning of the optimum detection operators.

  20. Models of optimum discrete signals on the vector combinatorial configurations

    Directory of Open Access Journals (Sweden)

    V. V. Riznyk

    2016-06-01

    Full Text Available Method for construction of optimum discrete signals, based on a new conceptual combinatorial model of the systems - Ideal Ring Vector sequences (clusters of the IRV is proposed. IRV clusters are cyclic ordered sequences of t- integer sub-sequences of sequence, which form perfect relationships of t-dimensional partitions over a virtual t-dimensional lattice covered surface of a finite space interval. The sums of connected sub-sequences of an IRV enumerate the set of t- coordinates specified with respect to cyclic frame reference exactly R-times. This property makes IRVs useful in applications, which need to partition multidimensional objects with the smallest possible number of intersections. There are discover a great class of new two- and multidimensional combinatorial constructions, which being in excess classic models of discrete systems with respect to number and combinatorial varieties with theoretically non-limited values of upper boundaries on order of dimensionality –IRV. It shows that remarkable properties of IRVs encoded in fine structure of torus circular symmetry. There are regarded basic properties these models and made shortest comparative analysis of the models with classical models. Indicate that the IRVs to be in exceed of difference sets multiply, and set of the classical difference sets is subset of the IRVs. Some of useful examples for constructing of the optimum discrete signals, error-correcting codes, and ring monolithic optimum vector codes using IRVs are considered. The problem statement involves development the regular method for construction of the optimum discrete signals using two- and multidimensional IRVs. The favorable technical merits of IRVs sets named “Gloria to Ukraine Stars”, which remarkable properties hold for the same set of the IRVs in varieties permutations of its terms is demonstrated, and method for design of two- or multidimensional vector signals coded based on the optimum binary monolithic

  1. Optimum conditions for enzymatic degradation of some oilseed proteins

    Directory of Open Access Journals (Sweden)

    El-Zanaty, E. A.

    2002-09-01

    Full Text Available Soybean, sesame seed, and rice bran meal proteins were hydrolyzed with two enzymes, namely, papain and bromelain. Experiments were carried out to elucidate the optimum condition for each enzyme when acting on each substrate seperately. Results revealed that the highest relative activities for papain were achieved with E/S 0.06 , 0.29, 0.19 and pH 7.2, 7.0, 7.0 for soybean, sesame,and rice bran meal proteins, respectively. Optimum temperature for papain while hydrolysing the three substrates was 50 ºC. When using bromelain optimum E/S resulting in highest relative activities were 0.067, 0.058 and 0.21 for soybean, sesame,and rice bran meal protein, respectively. Optimum pH was 6.0 and optimum temperature was 45 ºC for bromelain when hydrolysing the protein of the three substrates. A numerical correlation of enzymatic behaviour for the different substrates was calculated.Proteínas de haba de soja, semilla de sésamo y harina de germen de arroz se hidrolizaron con dos enzimas, denominadas, papaina y bromelaina. Se han llevado a cabo experimentos para determinar las condiciones óptimas de cada enzima cuando actúan separadamente sobre cada sustrato. Los resultados mostraron que las mayores actividades relativas para la papaina se consiguieron con una E/S 0,06, 0,29, 0,19 y un pH 7.2, 7.0, 7.0 para las proteínas de haba de soja, sésamo y harina de germen de arroz, respectivamente. La temperatura óptima para la papaina durante la hidrólisis de los tres sustratos fue de 50 ºC. Cuando se usa bromelaina las relaciones E/S óptimas que proporcionaron mayor actividad relativa fueron 0.067, 0.058 y 0.21 para las proteínas de habas de soja, sésamo y harina de germen de arroz respectivamente. El pH óptimo fue 6.0 y la temperatura óptima 45 ºC para la bromelaina cuando se hidroliza la proteína de los tres sustratos. Con estos datos se hizo una correlación numérica del comportamiento enzimático para los diferentes sustratos.

  2. [Baseline correction method for spectrum signal of SF6 insulating air with optimum wavelet basis].

    Science.gov (United States)

    Liu, Yan; Liu, Kai; Tao, Wei-Liang; Wang, Xian-Pei

    2010-06-01

    SF6 gas has been widely used in the power equipments as an excellent electric insulating and arc-quenching medium. In the present paper, a baseline correction method based on the optimum wavelet basis for spectrum detection is proposed to measure the composition content of the SF6 insulating gas to secure the power safety. In this method, the optimum wavelet basis is selected in the wavelet packet according to constructor function on the energy concentration criterion to express the spectrum signal in the time-frequency domain. Then the strong spectrum composition is removed from the spectrum signal with the threshold method to eliminate the interference with the continuous spectrum fitting. Finally we remove the continuous spectrum which is fitting result from the origin spectrum and obtain the useful signal of line spectrum. The intensities of spectral line processed with the proposed algorithm could reflect the concentration of the conponents to be measured in SF6 gas. Experiments to analyze the absorption spectrum of the SF6 insulating gas mixture show that the proposed algorithm can estimate and correct the drifting baseline accurately, and its performance is better than the algorithm based on iterative wavelet.

  3. Calculation of Ge0.5Si0.5-Si Superlattice Photodetectors on Ge0.05Si0.95 Waveguides:The Optimum Parameters①

    Institute of Scientific and Technical Information of China (English)

    1997-01-01

    The optimum parameters are calculated by the large cross-section theory and mode cut-off equation.The effect on reverse bias voltages in analysed by the doping concentration in n+-Si.The is significant because the reverse bias increases sharply when the doped concentration in n+-Si is less than 1×1020cm-3.

  4. Reliability Based Optimum Design of a Gear Box

    Directory of Open Access Journals (Sweden)

    D.Madhusekhar

    2014-10-01

    Full Text Available The gear box represents an important mechanical sub system. In machine tools, the propose of a gear box is to provide a series of useful output speeds so that the machining operation can be carried out at its most optimum operating conditions high spindle speeds with low feed rate for roughing operations. An important aspect in the design of machine tool transmission is to keep the cost and volume of the gear box to a minimum. The probabilistic approach to design has been considered to be more rational compared to the conventional design approach based on the factor of safety. The existence of uncertainties in either engineering simulations or manufacturing processes calls for a reliability-based design optimization (RBDO model for robust and cost-effective designs. In the present work a three shaft four speed gear box is designed using reliability principles. For the specified reliability of the system (Gear box, component reliability (Gear pair is calculated by considering the system as a series system. Design is considered to be safe and adequate if the probability of failure of gear box is less than or equal to a specified quantity in each of the two failure modes. A FORTRAN program has been developed to calculate the mean values of face widths of gears for the minimum mass of gear box. By changing the probability of failure of system variations in the face widths are studied. The reliability based optimum design results are compared with those obtained by deterministic optimum design. The minimum mass of the gear box is increase as the specified values of the reliability is increased.

  5. Optimum Thread Rolling Process That Improves SCC Resistance

    Energy Technology Data Exchange (ETDEWEB)

    A.R. Kephart

    2001-10-29

    Accelerated testing in environments aggressive for the specific material have shown that fastener threads that are rolled after strengthening heat treatments have improved resistance to SCC initiation. For example, intergranular SCC was produced in one day when machined (cut) threads of high strength steel (ASTM A193 B-7 and A354 Grade 8) were exposed to an aggressive aqueous environment containing 8 weight % boiling ammonium nitrate and stressed to about 40% of the steel's yield strength (120 ksi, 827 MPa). In similar testing conditions, fasteners that had threads rolled before heat-treatment (quench and temper) had similar susceptibility to SCC. However, threads rolled after strengthening, exhibited no SCC after a week of exposure, even when stressed to 100% of the B-7 alloy yield strength. Similarly, intergranular SCC was produced in less than one day when machined (cut) threads of nickel-base alloys (X-750 and aged 625) were exposed to an aggressive 750 F doped steam environment (containing 100 ppm of chloride, fluoride, sulfate, nitrate and a controlled hydrogen overpressure) and stressed to about 80% of the alloy yield strength (117 ksi, 807 MPa). In similar testing conditions, threads rolled after strengthening exhibited no SCC after 50 days of exposure. This beneficial effect of the optimum thread rolling process (i.e., threads rolled after strengthening) is due to the retention of large residual compressive stresses in the thread roots (notches) which mitigate the applied notch tensile stresses resulting from joint design pre-loads. use of these material specific aggressive environments can provide an accelerated test to verify that threads were produced by the optimum thread rolling process. These tests could support fastener acceptance criteria or failure analysis of fasteners with unknown or uncertain manufacturing processes. The optimum process effects may not always be detected by more conventional methods (e.g., metallography or hardness testing).

  6. DESIGN AND IMPLEMENTATION OF OPTIMUM INTERPOLATION FILTER USING FARROW STRUCTURE

    Directory of Open Access Journals (Sweden)

    NAVJOT SINGH,

    2011-05-01

    Full Text Available The Farrow Structure provides an efficient way to implement the interpolation filter using polynomialapproximation method for arbitrary sample rate change. The lagrange polynomial approximation method providesalmost exact reconstruction of the new interpolated signal as of the input sampled signal. In this paper, cubiclagrange polynomial and 4th order lagrange polynomial approximation methods have been used to implement thedesign of the interpolation filter based on Farrow Structure. The optimum filter coefficients have been calculatedusing both polynomial approximation methods. The performance of the two methods has been compared to get theoptimum solution to the design of the interpolation filter using Farrow structure.

  7. Fitness Landscape Analysis for Optimum Multiuser Detection Problem

    Institute of Scientific and Technical Information of China (English)

    WANG Shaowei; ZHU Qiuping

    2007-01-01

    Optimum multiuser detection (OMD) for CDMA systems is an NP-complete combinatorial optimization problem. Fitness landscape has been proven to be very useful for understanding the behavior of combinatorial optimization algorithms and can help in predicting their performance. This paper analyzes the statistic properties of the fitness landscape of the OMD problem by performing autocorrelation analysis, fitness distance correlation test and epistasis measure. The analysis results explain why some random search algorithms are effective methods for OMD problem and give hints how to design more efficient randomized search heuristic algorithms for OMD.

  8. Computing Optimum Heights for Balloon-Borne Radar

    Science.gov (United States)

    1993-11-01

    ducting, a " radar hole" against other raytrace niodels (IREPS, could develop. Although the radar beam. EREPS) that are considered accurate. The may be...TD-1369, Naval Ocean Systems Center, San Diego, CA, October 1985. ,quires, M.F., Caribbean Basin Radar Network Raytrace Study, USAPETAC/PR-91/005...IlI-AFETAC/PR-93IoO5 * AD-A286 832 COMPUTING OPTIMUM HEIGHTS for BALLOON-BORNE RADAR by Michael F. Squires IjxEA NOVEMBER 1993 DTIC QUAI’ii E’T" 2T

  9. Search for an optimum time response of spark counters

    CERN Document Server

    Devismes, A; Kress, T; Gobbi, A; Eschke, J; Herrmann, N; Hildenbrand, K D; Koczón, P; Petrovici, M

    2002-01-01

    A spark counter of the type developed by Pestov has been tested with the aim of searching for an optimum time response function, changing voltage, content of noble and quencher gases, pressure and energy-loss. Replacing the usual argon by neon has brought an improvement of the resolution and a significant reduction of tails in the time response function. It has been proven that a counter as long as 90 cm can deliver, using neon gas mixture, a time resolution sigma<60 ps with about 1% absolute tail and an efficiency of about 90%.

  10. Investigation of Various Essential Factors for Optimum Infrared Thermography

    Science.gov (United States)

    OKADA, Keiji; TAKEMURA, Kei; SATO, Shigeru

    2013-01-01

    ABSTRACT We investigated various essential factors for optimum infrared thermography for cattle clinics. The effect of various factors on the detection of surface temperature was investigated in an experimental room with a fixed ambient temperature using a square positioned on a wall. Various factors of animal objects were examined using cattle to determine the relationships among presence of hair, body surface temperature, surface temperature of the eyeball, the highest temperature of the eye circle, rectum temperature and ambient temperature. Also, the surface temperature of the flank at different time points after eating was examined. The best conditions of thermography for cattle clinics were determined and were as follows: (1) The distance between a thermal camera and an object should be fixed, and the camera should be set within a 45-degree angle with respect to the objects using the optimum focal length. (2) Factors that affect the camera temperature, such as extreme cold or heat, direct sunshine, high humidity and wind, should be avoided. (3) For the comparison of thermographs, imaging should be performed under identical conditions. If this is not achievable, hairless parts should be used. PMID:23759714

  11. Optimum Tower Crane Selection and Supporting Design Management

    Directory of Open Access Journals (Sweden)

    Hyo Won Sohn

    2014-08-01

    Full Text Available To optimize tower crane selection and supporting design, lifting requirements (as well as stability should be examined, followed by a review of economic feasibility. However, construction engineers establish plans based on data provided by equipment suppliers since there are no tools with which to thoroughly examine a support design’s suitability for various crane types, and such plans lack the necessary supporting data. In such cases it is impossible to optimize a tower crane selection to satisfy lifting requirements in terms of cost, and to perform lateral support and foundation design. Thus, this study is intended to develop an optimum tower crane selection and supporting design management method based on stability. All cases that are capable of generating an optimization of approximately 3,000 ~ 15,000 times are calculated to identify the candidate cranes with minimized cost, which are examined. The optimization method developed in the study is expected to support engineers in determining the optimum lifting equipment management.

  12. Reliability-based optimum inspection and maintenance procedures. [for engines

    Science.gov (United States)

    Nanagud, S.; Uppaluri, B.

    1975-01-01

    The development of reliability-based optimum inspection and maintenance schedules for engines needs an understanding of the fatigue behavior of the engines. Critical areas of the engine structure prone to fatigue damage are usually identified beforehand or after the fleet has been put into operation. In these areas, fatigue cracks initiate after several flight hours, and these cracks grow in length until failure takes place when these cracks attain the critical lengths. Crack initiation time and its growth rate are considered to be random variables. Usually, the inspection (fatigue) or test data from similar engines are used as prior distributions. The existing state-of-the-art is to ignore the different lengths of cracks obserbed at various inspections and to consider only the fact that a crack existed (or did not exist) at the time of inspection. In this paper, a procedure has been developed to obtain the probability of finding a crack of a given size at a certain time if the probability distributions for crack initiation and rates of growth are known. Application of the developed stochastic models to devise optimum procedures for inspection and maintenance are also discussed.

  13. Reliability-based optimum inspection and maintenance procedures. [for engines

    Science.gov (United States)

    Nanagud, S.; Uppaluri, B.

    1975-01-01

    The development of reliability-based optimum inspection and maintenance schedules for engines needs an understanding of the fatigue behavior of the engines. Critical areas of the engine structure prone to fatigue damage are usually identified beforehand or after the fleet has been put into operation. In these areas, fatigue cracks initiate after several flight hours, and these cracks grow in length until failure takes place when these cracks attain the critical lengths. Crack initiation time and its growth rate are considered to be random variables. Usually, the inspection (fatigue) or test data from similar engines are used as prior distributions. The existing state-of-the-art is to ignore the different lengths of cracks obserbed at various inspections and to consider only the fact that a crack existed (or did not exist) at the time of inspection. In this paper, a procedure has been developed to obtain the probability of finding a crack of a given size at a certain time if the probability distributions for crack initiation and rates of growth are known. Application of the developed stochastic models to devise optimum procedures for inspection and maintenance are also discussed.

  14. Optimum Tower Crane Selection and Supporting Design Management

    Directory of Open Access Journals (Sweden)

    Hyo Won Sohn

    2014-08-01

    Full Text Available To optimize tower crane selection and supporting design, lifting requirements (as well as stability should be examined, followed by a review of economic feasibility. However, construction engineers establish plans based on data provided by equipment suppliers since there are no tools with which to thoroughly examine a support design's suitability for various crane types, and such plans lack the necessary supporting data. In such cases it is impossible to optimize a tower crane selection to satisfy lifting requirements in terms of cost, and to perform lateral support and foundation design. Thus, this study is intended to develop an optimum tower crane selection and supporting design management method based on stability. All cases that are capable of generating an optimization of approximately 3,000 ˜ 15,000 times are calculated to identify the candidate cranes with minimized cost, which are examined. The optimization method developed in the study is expected to support engineers in determining the optimum lifting equipment management.

  15. Developments of optimum flip-chip bonding process

    Science.gov (United States)

    Jang, Dong H.; Kang, Sa Y.; Lee, Y. M.; Oh, S. Y.

    1997-08-01

    Flip-chip soldering is the critical technology for solving the current issues of electronic packaging industries that require the high I/O's. In order to increase the manufacturing ability of flip-chip technology, however, yield and reliability tissues should overcome. In this study, optimum flip-chip bonding process has been developed by using the test chips that had the electroplated solder bumps. Test chips are composed of three different types that are i) peripheral array pad chip, ii) peripheral array pad chip, and iii) area array pad chip. Each test chip has the daisy chain to consider the effect of reliability test. The electrical resistance was measured before and after reliability test. Based on these measurement, failure mode resulted from the moisture absorption was studied using scanning acoustic microscope. To achieve an optimum reflow profile of solder bump, correct temperature profile was set up with respect to the resin base flux. Different bonding forces were tested. Four underfill encapsulants were evaluated for minimum voids that caused the severe defects after reliability test. Also, the gap heights were measured with respect to applied bonding force after underfill was performed. Results from the moisture absorption and thermal cycling were discussed for flip-chip bonding on BT-resin substrates. The test vehicles using flip-chip technology have passed moisture preconditioning and temperature cycling tests.

  16. Optimum Transmitter Power Control in WCDMA Cellular Systems

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Power control is an important technique in WCDMA mobile systems for both increasing system capacity and guaranteeing the required QoS (time delay and wireless link transmission quality) of multimedia services. The optimum power control for narrow band CDMA cellular systems is a problem of single threshold optimization. Because these systems have only one type of traffic and have the same QoS requirement. However, WCDMA mobile systems should provide multimedia services and different types of traffic have different QoS requirements. Thus, the power control in WCDMA mobile systems doesn't be a problem of single threshold optimizing, but turns into the optimizing problem of multi-thresholds. In this paper, we analyze the power control problem in WCDMA cellular mobile systems and propose the optimum transmitter power control algorithm. Three criteria to optimize transmitter power levels of multi-thresholds based on grading the priority orders of multimedia services are proposed. Simulation results show that the proposed algorithms are more effective than conventional algorithms and can provide better performance for WCDMA cellular mobile systems.

  17. Carbon sequestration, optimum forest rotation and their environmental impact

    Energy Technology Data Exchange (ETDEWEB)

    Kula, Erhun, E-mail: erhun.kula@bahcesehir.edu.tr [Department of Economics, Bahcesehir University, Besiktas, Istanbul (Turkey); Gunalay, Yavuz, E-mail: yavuz.gunalay@bahcesehir.edu.tr [Department of Business Studies, Bahcesehir University, Besiktas, Istanbul (Turkey)

    2012-11-15

    Due to their large biomass forests assume an important role in the global carbon cycle by moderating the greenhouse effect of atmospheric pollution. The Kyoto Protocol recognises this contribution by allocating carbon credits to countries which are able to create new forest areas. Sequestrated carbon provides an environmental benefit thus must be taken into account in cost-benefit analysis of afforestation projects. Furthermore, like timber output carbon credits are now tradable assets in the carbon exchange. By using British data, this paper looks at the issue of identifying optimum felling age by considering carbon sequestration benefits simultaneously with timber yields. The results of this analysis show that the inclusion of carbon benefits prolongs the optimum cutting age by requiring trees to stand longer in order to soak up more CO{sub 2}. Consequently this finding must be considered in any carbon accounting calculations. - Highlights: Black-Right-Pointing-Pointer Carbon sequestration in forestry is an environmental benefit. Black-Right-Pointing-Pointer It moderates the problem of global warming. Black-Right-Pointing-Pointer It prolongs the gestation period in harvesting. Black-Right-Pointing-Pointer This paper uses British data in less favoured districts for growing Sitka spruce species.

  18. Sensitivity of salad greens (Lactuca sativa L. and Eruca sativa Mill.) exposed to crude extracts of toxic and non-toxic cyanobacteria.

    Science.gov (United States)

    Bittencourt-Oliveira, M C; Hereman, T C; Macedo-Silva, I; Cordeiro-Araújo, M K; Sasaki, F F C; Dias, C T S

    2015-05-01

    We evaluated the effect of crude extracts of the microcystin-producing (MC+) cyanobacteria Microcystis aeruginosa on seed germination and initial development of lettuce and arugula, at concentrations between 0.5 μg.L(-1) and 100 μg.L(-1) of MC-LR equivalent, and compared it to crude extracts of the same species without the toxin (MC-). Crude extracts of the cyanobacteria with MC (+) and without MC (-) caused different effects on seed germination and initial development of the salad green seedlings, lettuce being more sensitive to both extracts when compared to arugula. Crude extracts of M. aeruginosa (MC+) caused more evident effects on seed germination and initial development of both species of salad greens than MC-. Concentrations of 75 μg.L(-1) and 100 μg.L(-1) of MC-LR equivalent induced a greater occurrence of abnormal seedlings in lettuce, due to necrosis of the radicle and shortening of this organ in normal seedlings, as well as the reduction in total chlorophyll content and increase in the activity of the antioxidant enzyme peroxidase (POD). The MC- extract caused no harmful effects to seed germination and initial development of seedlings of arugula. However, in lettuce, it caused elevation of POD enzyme activity, decrease in seed germination at concentrations of 75 μg.L(-1) (MC-75) and 100 μg.L(-1) (MC-100), and shortening of the radicle length, suggesting that other compounds present in the cyanobacteria extracts contributed to this result. Crude extracts of M. aeruginosa (MC-) may contain other compounds, besides the cyanotoxins, capable of causing inhibitory or stimulatory effects on seed germination and initial development of salad green seedlings. Arugula was more sensitive to the crude extracts of M. aeruginosa (MC+) and (MC-) and to other possible compounds produced by the cyanobacteria.

  19. Sensitivity of salad greens (Lactuca sativa L. and Eruca sativa Mill. exposed to crude extracts of toxic and non-toxic cyanobacteria

    Directory of Open Access Journals (Sweden)

    MC. Bittencourt-Oliveira

    Full Text Available We evaluated the effect of crude extracts of the microcystin-producing (MC+ cyanobacteria Microcystis aeruginosa on seed germination and initial development of lettuce and arugula, at concentrations between 0.5 μg.L–1 and 100 μg.L–1 of MC-LR equivalent, and compared it to crude extracts of the same species without the toxin (MC–. Crude extracts of the cyanobacteria with MC (+ and without MC (– caused different effects on seed germination and initial development of the salad green seedlings, lettuce being more sensitive to both extracts when compared to arugula. Crude extracts of M. aeruginosa (MC+ caused more evident effects on seed germination and initial development of both species of salad greens than MC–. Concentrations of 75 μg.L–1 and 100 μg.L–1 of MC–LR equivalent induced a greater occurrence of abnormal seedlings in lettuce, due to necrosis of the radicle and shortening of this organ in normal seedlings, as well as the reduction in total chlorophyll content and increase in the activity of the antioxidant enzyme peroxidase (POD. The MC– extract caused no harmful effects to seed germination and initial development of seedlings of arugula. However, in lettuce, it caused elevation of POD enzyme activity, decrease in seed germination at concentrations of 75 μg.L–1 (MC-75 and 100 μg.L–1 (MC-100, and shortening of the radicle length, suggesting that other compounds present in the cyanobacteria extracts contributed to this result. Crude extracts of M. aeruginosa (MC– may contain other compounds, besides the cyanotoxins, capable of causing inhibitory or stimulatory effects on seed germination and initial development of salad green seedlings. Arugula was more sensitive to the crude extracts of M. aeruginosa (MC+ and (MC– and to other possible compounds produced by the cyanobacteria.

  20. Performance of a slurry bubble column reactor for Fischer-Tropsch synthesis: Determination of optimum condition

    Energy Technology Data Exchange (ETDEWEB)

    Woo, Kwang-Jae; Kang, Suk-Hwan; Kim, Seung-Moon; Bae, Jong-Wook; Jun, Ki-Won [Advanced Chemical Technology Division, Korea Research Institute of Chemical Technology (KRICT), P.O. Box 107, Yuseong, Daejeon 305-600 (Korea)

    2010-04-15

    The CO conversion and selectivity to C{sub 1}+ and C{sub 11}+ wax products over Co/Al{sub 2}O{sub 3} as well as Ru/Co/Al{sub 2}O{sub 3} Fischer-Tropsch (F-T)catalysts were investigated by varying reaction temperature (210-250 C), system pressure (1.0-3.0 MPa), GHSV (1000-6000 L/kg/h), superficial gas velocity (1.7-13.6 cm/s) and slurry concentration (9.09-26.67 wt.%) in a slurry bubble column reactor (0.05 m diameter x 1.5 m height) to determine the optimum operating conditions. Squalane or paraffin wax was used as initial liquid media. The overall CO conversion increased with increasing reaction temperature, system pressure and catalyst concentration. However, the local maximum CO conversion was exhibited at GHSV of 1500-2000 L/kg/h and superficial gas velocity of 3.4-5.0 cm/s. The CO conversion in the case of Ru/Co/Al{sub 2}O{sub 3} was much higher and stable than that in the case of Co/Al{sub 2}O{sub 3}. The selectivity to C{sub 11}+ wax products increased slightly with increasing GHSV; on the other hand, it decreased with increasing reaction temperature, system pressure, and solid concentration in a slurry bubble column reactor. It could be concluded that the optimum operating conditions based on the yield of hydrocarbons and wax products were; U{sub G} 6.8-10 cm/s, Cs = 15 wt.%, T = 220-230 C, P = 2.0 MPa in a slurry bubble column reactor for F-T synthesis. (author)

  1. Cheap non-toxic non-corrosive method of glass cleaning evaluated by contact angle, AFM, and SEM-EDX measurements.

    Science.gov (United States)

    Dey, Tania; Naughton, Daragh

    2017-05-01

    Glass surface cleaning is the very first step in advanced coating deposition and it also finds use in conserving museum objects. However, most of the wet chemical methods of glass cleaning use toxic and corrosive chemicals like concentrated sulfuric acid (H2SO4), piranha (a mixture of concentrated sulfuric acid and 30% hydrogen peroxide), and hydrogen fluoride (HF). On the other hand, most of the dry cleaning techniques like UV-ozone, plasma, and laser treatment require costly instruments. In this report, five eco-friendly wet chemical methods of glass cleaning were evaluated in terms of contact angle (measured by optical tensiometer), nano-scale surface roughness (measured by atomic force microscopy or AFM), and elemental composition (measured by energy dispersive x-ray spectroscopy or SEM-EDX). These glass cleaning methods are devoid of harsh chemicals and costly equipment, hence can be applied in situ in close proximity with plantation such as greenhouse or upon subtle objects such as museum artifacts. Out of these five methods, three methods are based on the chemical principle of chelation. It was found that the citric acid cleaning method gave the greatest change in contact angle within the hydrophilic regime (14.25° for new glass) indicating effective cleansing and the least surface roughness (0.178 nm for new glass) indicating no corrosive effect. One of the glass sample showed unique features which were traced backed to the history of the glass usage.

  2. Selection of the Optimum Electrospray Voltage for Gradient Elution LC-MS Measurements

    Science.gov (United States)

    Marginean, Ioan; Kelly, Ryan T.; Moore, Ronald J.; Prior, David C.; LaMarche, Brian L.; Tang, Keqi; Smith, Richard D.

    2009-01-01

    Changes in liquid composition during gradient elution liquid chromatography (LC) coupled to mass spectrometry (MS) analyses affect the electrospray operation. To establish methodologies for judicious selection of the electrospray voltage, we monitored in real-time the effect of the LC gradient on the spray current. The optimum range of the electrospray voltage decreased as the concentration of organic solvent in the eluent increased during reversed-phase LC analyses. These results provided the means to rationally select the voltage so as to ensure effective electrospray operation throughout gradient-elution LC separations. For analyses in which the electrospray was operated at constant voltage, a small run-to-run variation in the spray current was observed, indicating a changing electric field due to fouling or degradation of the emitter. Algorithms using feedback from spray current measurements to maintain the electrospray voltage within the optimum operating range throughout gradient elution LC-MS were evaluated. The electrospray operation with voltage regulation and at a constant, judiciously selected voltage during gradient elution LC-MS measurements produced data with similar reproducibility. SYNOPSIS Electrospray current measurements during gradient elution liquid chromatography analyses provide reliable feedback for monitoring, understanding, and improving performance. PMID:19196520

  3. Selection of the Optimum Electrospray Voltage for Gradient Elution LC-MS Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Marginean, Ioan; Kelly, Ryan T.; Moore, Ronald J.; Prior, David C.; Lamarche, Brian L.; Tang, Keqi; Smith, Richard D.

    2009-04-01

    Changes in liquid composition during gradient elution liquid chromatography (LC) and mass spectrometry (MS) analyses affect the electrospray operation. To establish methodologies for judicious selection of the electrospray voltage, we monitored in real-time the effect of the LC gradient on the spray current. The optimum range of the electrospray voltage shifted to lower values as the concentration of organic solvent in the eluent increased during reversed-phase LC analyses. These results provided the means to rationally select the voltage that ensured successful electrospray operation throughout gradient elution LC-MS experiments. A small run-to-run drift in the spray current was observed for electrosprays operated at constant voltage. This could be the result of fouling or degradation of the electrospray emitter, which affected the electric field driving the electrospray. Algorithms using feedback from spray current measurements to maintain the electrospray voltage within the optimum operating range throughout gradient elution LC-MS were evaluated. The electrospray operation with voltage regulation and at constant, judiciously selected voltage during gradient elution LC-MS measurements produced data with similar reproducibility.

  4. OPTIMUM, CRITICAL AND THRESHOLD VALUES FOR WATER OXYGENATION FOR MULLETS (MUGILIDAE AND FLATFISHES (PLEURONECTIDAE IN ONTOGENESIS

    Directory of Open Access Journals (Sweden)

    P. Shekk

    2014-12-01

    Full Text Available Purpose. To determine the optimum, critical, and threshold values of water oxygenation for embryos, larvae and fingerlings of mullets and flatfishes under different temperature conditions. Methodology. Oxygen consumption was studied in chronic experiments with «interrupted flow» method with automatic fixation of dissolved oxygen in water with the aid of an oxygen sensor and automatic, continuous recording of the obtained results. «Critical» (Pcrit., and the «threshold» (Pthr. oxygen tension in the water have been determined. Findings. Under optimum conditions, the normal embryogenesis of mullets and flatfish to the gastrulation stage, provided 90–130% oxygen saturation. The critical content was 80–85%, the threshold – 65–70% of the saturation. At the stage of «movable embryo» depending on water temperature and fish species, the optimum range of water oxygenation was within 70‒127.1%. The most tolerant to oxygen deficiency was flounder Platichthys luscus (Pcrit – 25.4–27,5; Pthr. – 20.5–22.5%, the least resistant to hypoxia was striped mullet Mugil серhalus (Pcrit. – 50–60; Pthr. – 35–40%. The limits of the critical and threshold concentration of dissolved oxygen directly depended on the temperature and salinity, at which embryogenesis occurred. An increase in water temperature and salinity resulted in an increase in critical and threshold values for oxygen tension embryos. Mullet and flatfish fingerlings in all stages of development had a high tolerance to hypoxia, which increased as they grew. They were resistant to the oversaturation of water with oxygen. The most demanding for the oxygen regime are larvae and fingerlings of striped mullet and Liza aurata. Hypoxia tolerance of Psetta maeoticus (Psetta maeoticus and flounder at all stages of development is very high. The fingerlings of these species can endure reduction of the dissolved oxygen in water to 2.10 and 1.65 mgO2/dm3 respectively for a long time

  5. Synthesis and characterization of non-toxic and thermo-sensitive poly(N-isopropylacrylamide)-grafted cashew gum nanoparticles as a potential epirubicin delivery matrix.

    Science.gov (United States)

    Abreu, Clara M W S; Paula, Haroldo C B; Seabra, Vitor; Feitosa, Judith P A; Sarmento, Bruno; de Paula, Regina C M

    2016-12-10

    Cashew gum (CG) was grafted with N-isopropylacrylamide (NIPA) by radical polymerization to originate a stimuli-sensitive copolymer for drug delivery purposes. NMR and IR spectroscopy confirmed the insertion of NIPA onto the cashew gum chains. The graft copolymer (CG:NIPA) demonstrated thermal responsiveness. The critical aggregation concentration of the copolymers at 25°C was higher than at 50°C. At temperatures lower than the LCST, the nanoparticle size ranged from 12 to 21nm, depending on the CG:NIPA ratio, but above the LCST the particles aggregated, increasing the particle size. Regarding the potential for future oral application, the nanoparticles showed no cytotoxic activity against the Caco-2 and HT29-MTX intestine cell lines. Epirubicin was encapsulated into nanoparticles of CG-NIPA (1:1), resulting in a 64% association efficiency and 22% loading capacity. Thus, the CG:NIPA graft copolymer demonstrates good potential for used in controlled drug delivery systems.

  6. A potent, non-toxic insulin-releasing peptide isolated from an extract of the skin of the Asian frog, Hylarana guntheri (Anura:Ranidae).

    Science.gov (United States)

    Conlon, J Michael; Power, Gavin J; Abdel-Wahab, Yasser H A; Flatt, Peter R; Jiansheng, Hu; Coquet, Laurent; Leprince, Jérôme; Jouenne, Thierry; Vaudry, Hubert

    2008-11-29

    Peptides in extract of the skin of the Asian frog Hylarana guntheri Boulenger,1882 were purified by reversed-phase HPLC and individual components analysed for their ability to release insulin from the rat BRIN-BD11 clonal beta cell line. The most potent peptide identified in the extract belonged to the brevinin-2 family (brevinin-2GUb; GVIIDTLKGAAKTVAAELLRKAHCKLTNSC). Other peptides with weaker insulin-releasing activity belonged to the brevinin-1 (2 peptides), brevinin-2 (2 peptides) and temporin (3 peptides) families. Only the brevinin-1 peptides showed cytolytic activity against the BRIN-BD11 cells, as demonstrated by an increased rate of release of the cytosolic enzyme, lactate dehydrogenase. A synthetic replicate of brevinin-2GUb produced a significant stimulation of insulin release (139% of basal rate; P<0.05) at a concentration of 100 nM with a maximum response of 373% of basal rate at a concentration of 3 microM) by a mechanism that did not involve mobilization of intracellular calcium. Brevinin-2GUb also inhibited the growth of microorganisms (MIC against Escherichia coli=32 microM, Staphylococcus aureus=64 microM, and Candida albicans=64 microM) but had only weak hemolytic activity against human erythrocytes (LC(50)=700 microM). Administration of brevinin-2GUb (75 nmol/kg body weight) into mice significantly (P<0.05) improved glucose tolerance following a intraperitoneal injection of glucose, thereby demonstrating that the peptide shows potential for development into a therapeutically valuable agent for the treatment of Type 2 diabetes.

  7. OPTIMUM DESIGN AND NON-LINEAR MODEL OF POWERPLANT HYDRAULIC MOUNT SYSTEM

    Institute of Scientific and Technical Information of China (English)

    Shi Wenku; Min Haitao; Dang Zhaolong

    2003-01-01

    6-DOF non-linear mechanics model of powerplant hydraulic mount system is established. Optimum design of the powerplant hydraulic mount system is made with the hydraulic mount parameters as variables and with uncoupling of energy, rational disposition of nature frequency and minimum of reactive force at mount's location as objective functions. And based on the optimum design, software named ODPHMS (optimum design of powerplant hydraulic mount system) used in powerplant mount system optimum design is developed.

  8. Survival analysis: A consumer-friendly method to estimate the optimum sucrose level in probiotic petit suisse.

    Science.gov (United States)

    Esmerino, E A; Paixão, J A; Cruz, A G; Garitta, L; Hough, G; Bolini, H M A

    2015-11-01

    For years, just-about-right (JAR) scales have been among the most used techniques to obtain sensory information about consumer perception, but recently, some researchers have harshly criticized the technique. The present study aimed to apply survival analysis to estimate the optimum sucrose concentration in probiotic petit suisse cheese and compare the survival analysis to JAR scales to verify which technique more accurately predicted the optimum sucrose concentration according to consumer acceptability. Two panels of consumers (total=170) performed affective tests to determine the optimal concentration of sucrose in probiotic petit suisse using 2 different methods of analysis: JAR scales (n=85) and survival analysis (n=85). Then an acceptance test was conducted using naïve consumers (n=100) between 18 and 60 yr old, with 2 samples of petit suisse, one with the ideal sucrose determined by JAR scales and the other with the ideal sucrose content determined by survival analysis, to determine which formulation was in accordance with consumer acceptability. The results indicate that the 2 sensory methods were equally effective in predicting the optimum sucrose level in probiotic petit suisse cheese, and no significant differences were detected in any of the characteristics related to liking evaluated. However, survival analysis has important advantages over the JAR scales. Survival analysis has shown the potential to be an advantageous tool for dairy companies because it was able to accurately predict the optimum sucrose content in a consumer-friendly way and was also practical for researchers because experimental sensory work is simpler and has been shown to be more cost effective than JAR scales without losses of consumer acceptability.

  9. Optimum Efficient Mobility Management Scheme for IPv6

    Directory of Open Access Journals (Sweden)

    Virender Kumar

    2012-10-01

    Full Text Available Mobile IPv6 (MIPv6 and Hierarchical Mobile IPv6 (HMIPv6 both are the mobility management solutionsproposed by the Internet Engineering Task Force (IETF to support IP Mobility. It’s been an importantissue, that upon certain condition, out of MIPv6 and HMIPv6 which one is better. In this paper anOptimum Efficient Mobility Management (OEMM scheme is described on the basis of analytical modelwhich shows that OEMM Scheme is better in terms of performance and applicability of MIPv6 andHMIPv6. It shows that which one is better alternative between MIPv6 and HMIPv6 and if HMIPv6 isadopted it chooses the best Mobility Anchor Point (MAP. Finally it is illustrated that OEMM scheme isbetter than that of MIPv6 and HMIPv6.

  10. Narratives of Optimum Currency Area theory and Eurozone Governance

    DEFF Research Database (Denmark)

    Snaith, Holly Grace

    2014-01-01

    suppressed, capitalising upon the fundamental uncertainty in the theory itself. The final part of the paper goes on to consider the financial crisis, and how OCA theory might aid policy-makers’ attempts to induce ex-post convergence, demonstrating the continued relevance of the theory.......Optimum Currency Area theory (OCA) is a body of research that has, since its inception in 1961, been highly influential for the discourse and design of Economic and Monetary Union, exercising a significant hermeneutical force. Nonetheless, there has been little acknowledgement that OCA...... is the subject of very significant internal disagreement, to the extent that economists writing within the field do not commonly agree upon the ontological foundations of the theory. This entails that the translation of the theory into political reality has been characterised by a series of often mutually...

  11. Optimum design of band-gap beam structures

    DEFF Research Database (Denmark)

    Olhoff, Niels; Niu, Bin; Cheng, Gengdong

    2012-01-01

    -sectional area. To study the band-gap for travelling waves, a repeated inner segment of the optimized beams is analyzed using Floquet theory and the waveguide finite element (WFE) method. Finally, the frequency response is computed for the optimized beams when these are subjected to an external time......The design of band-gap structures receives increasing attention for many applications in mitigation of undesirable vibration and noise emission levels. A band-gap structure usually consists of a periodic distribution of elastic materials or segments, where the propagation of waves is impeded...... or significantly suppressed for a range of external excitation frequencies. Maximization of the band-gap is therefore an obvious objective for optimum design. This problem is sometimes formulated by optimizing a parameterized design model which assumes multiple periodicity in the design. However, it is shown...

  12. Optimum hot water temperature for absorption solar cooling

    Energy Technology Data Exchange (ETDEWEB)

    Lecuona, A.; Ventas, R.; Venegas, M.; Salgado, R. [Dpto. Ingenieria Termica y de Fluidos, Universidad Carlos III de Madrid, Avda. Universidad 30, 28911 Leganes, Madrid (Spain); Zacarias, A. [ESIME UPA, IPN, Av. de las Granjas 682, Col. Santa Catarina, 02550, D.F. Mexico (Mexico)

    2009-10-15

    The hot water temperature that maximizes the overall instantaneous efficiency of a solar cooling facility is determined. A modified characteristic equation model is used and applied to single-effect lithium bromide-water absorption chillers. This model is based on the characteristic temperature difference and serves to empirically calculate the performance of real chillers. This paper provides an explicit equation for the optimum temperature of vapor generation, in terms of only the external temperatures of the chiller. The additional data required are the four performance parameters of the chiller and essentially a modified stagnation temperature from the detailed model of the thermal collector operation. This paper presents and discusses the results for small capacity machines for air conditioning of homes and small buildings. The discussion highlights the influence of the relevant parameters. (author)

  13. Nanoscale tailored plasmonic material for optimum broadband solar harvesting

    Science.gov (United States)

    Zerulla, Dominic; McClean-Ilten, Éadaoin

    2016-09-01

    Is it possible to design a dedicated nanostructure on which all surface features contribute entirely to energy harvesting within a solar cell? This is an important challenge in the light that the efficiency of the solar cell technology utilised has a direct impact on the required land-use and also on reaching grid parity. Here, we take a unique approach and present an analytically derived optimum solution to the problem: a nanoscale metal topography, capable of significantly improving the efficiency of solid state solar cells via excitation of surface plasmon polaritons (SPPs). The presented structure is designed to achieve broadband excitation of SPPs through the highest possible density of desired k-vectors at the interface. This leads to high weighted absorption enhancements (>130%) and unprecedented improvements (>30%) of solar cell external quantum efficiencies over the entire harvestable range.

  14. Study on optimum arrangement of hysteretic dampers in frame structure

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The earthquake mitigation effect of hysteretic dampers is not only related to the number, stiffness,strength, deformation ability of dampers but also to the strength and stiffness of the structure. This paper studied the condition that structures should be in when the hysteretic dampers mitigated seismic action most effectively and made appropriate numerical analysis to verify the effectiveness of theory derivation. The inelastic seismic responses were analyzed for the SDOF system that the shear strength ratio of the damper system was taken differently and the result showed that when the ratio was in the vicinity of the optimum strength ratio of the damper system, the displacement of the structure was minimum and the energy dissipation of dampers was maximum, which indicated that the dampers mitigated seismic action most effectively. The result also indicated that the hysteretic dampers had significant earthquake mitigation effect when the strength ratio β changed in a relatively wide range.

  15. Optimum Transmission Policies for Battery Limited Energy Harvesting Nodes

    CERN Document Server

    Tutuncuoglu, Kaya

    2010-01-01

    Wireless networks with energy harvesting battery powered nodes are quickly emerging as a viable option for future wireless networks with extended lifetime. Equally important to their counterpart in the design of energy harvesting radios are the design principles that this new networking paradigm calls for. In particular, unlike wireless networks considered up to date, the energy replenishment process and the storage constraints of the rechargeable batteries need to be taken into account in designing efficient transmission strategies. In this work, we consider such transmission policies for rechargeable nodes, and identify the optimum solution for two related problems. Specifically, the transmission policy that maximizes the short term throughput, i.e., the amount of data transmitted in a finite time horizon is found. In addition, we show the relation of this optimization problem to another, namely, the minimization of the transmission completion time for a given amount of data, and solve that as well. The tra...

  16. Adjoint method for the optimum planning of industrial pollutant sources

    Institute of Scientific and Technical Information of China (English)

    LIU Feng; HU Fei; ZHU Jiang

    2005-01-01

    The optimum planning of industrial pollutant sources, which optimizes the economic object without violating environmental constraints, is an important and hard task to be conquered. In this paper, an adjoint method is developed to solve the problem. The penalty function is introduced to deal with the environmental inequality constraints, and Lagrange function is constructed to derive the adjoint equation and the gradient of the object function. In this means, the gradient of the object function can be calculated by solving the adjoint equation, and the information from the gradient is used to make the object function descend and approach to an optimal solution after some iterations. A two-dimensional, simplified model is used for numerical experiments. The theoretical derivations are verified by the results of the experiments. Furthermore, the adjoint method is shown to be of excellent convergence and efficiency, which is adaptive to the fast development of air quality numerical models and super computers.

  17. Optimum linear array of an optical aperture synthesis telescope

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Measuring out successively the degree of coherence of the source produced by any couple of the small apertures via rotating an array composed of the small aperture telescopes, and synthesizing them into the (u, v) coverage of the source, the brightness distribution of the source can be obtained by the inverse Fourier transform of the degree of coherence with much higher resolution than from a single telescope. This article discusses the arrangements of the small apertures in the linear array, and found a method to decide the quality of the arrangements. the judgment factor ? is introduced to calculate the arrangements in quantity. There are 1.5×1011 possibilities for 11 apertures. Therefore, the computer procedures are programmed to select the optimum arrangements. The effect of the simulation of the aperture synthesis is given for the linear array. The simulation method can also be used in the nonlinear arrays.

  18. Optimum Identification Method of Sorting Green Household Waste

    Directory of Open Access Journals (Sweden)

    Daud Mohd Hisam

    2016-01-01

    Full Text Available This project is related to design of sorting facility for reducing, reusing, recycling green waste material, and in particular to invent an automatic system to distinguish household waste in order to separate them from the main waste stream. The project focuses on thorough analysis of the properties of green household waste. The method of identification is using capacitive sensor where the characteristic data taken on three different sensor drive frequency. Three types of material have been chosen as a medium of this research, to be separated using the selected method. Based on capacitance characteristics and its ability to penetrate green object, optimum identification method is expected to be recognized in this project. The output capacitance sensor is in analogue value. The results demonstrate that the information from the sensor is enough to recognize the materials that have been selected.

  19. Optimum intermediate fibers for reducing interconnection loss: exact solution.

    Science.gov (United States)

    Yablon, Andrew D; Sumetsky, M

    2007-03-15

    We derive an exact analytical solution for a transmission line of N single-mode intermediate optical fibers that minimize the interconnection loss between any two dissimilar fiber modes that are well described by that paraxial scalar wave equation. Our solution shows that N optimum intermediate fibers reduce the original interconnection loss by a factor of least 1/(N+1) and that the total interconnection loss is only a function of N and the original direct interconnection loss. Our solution is not restricted to axisymmetric fibers or mode fields and therefore could be useful for reducing the interconnection loss between microstructured optical fibers, between certain slab waveguides, or between fibers and optical sources or detectors.

  20. Optimum selection of an energy resource using fuzzy logic

    Energy Technology Data Exchange (ETDEWEB)

    Abouelnaga, Ayah E., E-mail: ayahabouelnaga@hotmail.co [Nuclear Engineering Department, Faculty of Engineering, Alexandria University, 21544 Alexandria (Egypt); Metwally, Abdelmohsen; Nagy, Mohammad E.; Agamy, Saeed [Nuclear Engineering Department, Faculty of Engineering, Alexandria University, 21544 Alexandria (Egypt)

    2009-12-15

    Optimum selection of an energy resource is a vital issue in developed countries. Considering energy resources as alternatives (nuclear, hydroelectric, gas/oil, and solar) and factors upon which the proper decision will be taken as attributes (economics, availability, environmental impact, and proliferation), one can use the multi-attribute utility theory (MAUT) to optimize the selection process. Recently, fuzzy logic is extensively applied to the MAUT as it expresses the linguistic appraisal for all attributes in wide and reliable manners. The rise in oil prices and the increased concern about environmental protection from CO{sub 2} emissions have promoted the attention to the use of nuclear power as a viable energy source for power generation. For Egypt, as a case study, the nuclear option is found to be an appropriate choice. Following the introduction of innovative designs of nuclear power plants, improvements in the proliferation resistance, environmental impacts, and economics will enhance the selection of the nuclear option.

  1. Impedance matching, optimum velocity, and ideal middle ears.

    Science.gov (United States)

    Peake, W T; Rosowski, J J

    1991-05-01

    One way to assess an ear's performance as a receiver of acoustic power is to consider impedance matching at the tympanic membrane. Assumptions about some of the impedances involved have lead to the idea of an optimum velocity magnitude (per unit pressure), which has been used as a test of middle-ear performance. We show that this approach is not a realistic way to assess effectiveness of power absorption at the tympanic membrane. More generally, we suggest that, if the performance of the combined external-and-middle ear in collecting acoustic power and delivering it to the inner ear is considered, the external- and middle-ear power-transfer efficiencies, as well as impedance matching, are involved in relating performance to an ideal.

  2. Performance-Optimum Superscalar Architecture for Embedded Applications

    CERN Document Server

    Alipour, Mehdi

    2012-01-01

    Embedded applications are widely used in portable devices such as wireless phones, personal digital assistants, laptops, etc. High throughput and real time requirements are especially important in such data-intensive tasks. Therefore, architectures that provide the required performance are the most desirable. On the other hand, processor performance is severely related to the average memory access delay, number of processor registers and also size of the instruction window and superscalar parameters. Therefore, cache, register file and superscalar parameters are the major architectural concerns in designing a superscalar architecture for embedded processors. Although increasing cache and register file size leads to performance improvements in high performance embedded processors, the increased area, power consumption and memory delay are the overheads of these techniques. This paper explores the effect of cache, register file and superscalar parameters on the processor performance to specify the optimum size ...

  3. Optimum Location of Thermal Radiation Shield in Superconducting Rotating Machines

    Science.gov (United States)

    Saikiran, P. A.; Rao, V. V.

    2017-02-01

    Superconducting rotating machines have rotor maintained at low temperatures, below the critical temperature of the superconductor. This establishes large temperature difference between the cold rotor and surroundings, resulting in large heat leak into rotor through conduction, convection and radiation. Minimizing this heat leak is essential to reduce the power expense of cryogenic cooling system. A radiation shield is anchored at a suitable location on torque tube to minimize the radiation heat leak into the cold rotor. This paper presents a methodology to determine the optimum location of this anchor-point of radiation shield for a given geometry, which minimizes the total heat leak into cold rotor. The location of radiation shield is found to be depending on emissivity of cold rotor.

  4. Optimum spatiotemporal receptive fields for vision in dim light.

    Science.gov (United States)

    Klaus, Andreas; Warrant, Eric J

    2009-04-22

    Many nocturnal insects depend on vision for daily life and have evolved different strategies to improve their visual capabilities in dim light. Neural summation of visual signals is one strategy to improve visual performance, and this is likely to be especially important for insects with apposition compound eyes. Here we develop a model to determine the optimum spatiotemporal sampling of natural scenes at gradually decreasing light levels. Image anisotropy has a strong influence on the receptive field properties predicted to be optimal at low light intensities. Spatial summation between visual channels is predicted to extend more strongly in the direction with higher correlations between the input signals. Increased spatiotemporal summation increases signal-to-noise ratio at low frequencies but sacrifices signal-to-noise ratio at higher frequencies. These results, while obtained from a model of the insect visual system, are likely to apply to visual systems in general.

  5. Optimum investment strategy in the power industry mathematical models

    CERN Document Server

    Bartnik, Ryszard; Hnydiuk-Stefan, Anna

    2016-01-01

    This book presents an innovative methodology for identifying optimum investment strategies in the power industry. To do so, it examines results including, among others, the impact of oxy-fuel technology on CO2 emissions prices, and the specific cost of electricity production. The technical and economic analysis presented here extend the available knowledge in the field of investment optimization in energy engineering, while also enabling investors to make decisions involving its application. Individual chapters explore the potential impacts of different factors like environmental charges on costs connected with investments in the power sector, as well as discussing the available technologies for heat and power generation. The book offers a valuable resource for researchers, market analysts, decision makers, power engineers and students alike.

  6. The optimum choice of gate width for neutron coincidence counting

    Science.gov (United States)

    Croft, S.; Henzlova, D.; Favalli, A.; Hauck, D. K.; Santi, P. A.

    2014-11-01

    In the measurement field of international nuclear safeguards, passive neutron coincidence counting is used to quantify the spontaneous fission rate of certain special nuclear materials. The shift register autocorrelation analysis method is the most commonly used approach. However, the Feynman-Y technique, which is more commonly applied in reactor noise analysis, provides an alternative means to extract the correlation information from a pulse train. In this work we consider how to select the optimum gate width for each of these two time-correlation analysis techniques. The optimum is considered to be that which gives the lowest fractional precision on the net doublets rate. Our theoretical approach is approximate but is instructional in terms of revealing the key functional dependence. We show that in both cases the same performance figure of merit applies so that common design criteria apply to the neutron detector head. Our prediction is that near optimal results, suitable for most practical applications, can be obtained from both techniques using a common gate width setting. The estimated precision is also comparable in the two cases. The theoretical expressions are tested experimentally using 252Cf spontaneous fission sources measured in two thermal well counters representative of the type in common use by international inspectorates. Fast accidental sampling was the favored method of acquiring the Feynman-Y data. Our experimental study confirmed the basic functional dependences predicted although experimental results when available are preferred. With an appropriate gate setting Feynman-Y analysis provides an alternative to shift register analysis for safeguards applications which is opening up new avenues of data collection and data reduction to explore.

  7. The optimum choice of gate width for neutron coincidence counting

    Energy Technology Data Exchange (ETDEWEB)

    Croft, S., E-mail: crofts@ornl.gov [Safeguards and Security Technology (SST), Global Nuclear Security Technology Divisions, PO Box 2008, Building 5700, MS-6166, Oak Ridge, TN 37831-6166 (United States); Henzlova, D.; Favalli, A.; Hauck, D.K.; Santi, P.A. [Safeguards Science and Technology Group (NEN-1), Nuclear Engineering and Nonproliferation Division, MS-E540, Los Alamos, NM 87545 (United States)

    2014-11-11

    In the measurement field of international nuclear safeguards, passive neutron coincidence counting is used to quantify the spontaneous fission rate of certain special nuclear materials. The shift register autocorrelation analysis method is the most commonly used approach. However, the Feynman-Y technique, which is more commonly applied in reactor noise analysis, provides an alternative means to extract the correlation information from a pulse train. In this work we consider how to select the optimum gate width for each of these two time-correlation analysis techniques. The optimum is considered to be that which gives the lowest fractional precision on the net doublets rate. Our theoretical approach is approximate but is instructional in terms of revealing the key functional dependence. We show that in both cases the same performance figure of merit applies so that common design criteria apply to the neutron detector head. Our prediction is that near optimal results, suitable for most practical applications, can be obtained from both techniques using a common gate width setting. The estimated precision is also comparable in the two cases. The theoretical expressions are tested experimentally using {sup 252}Cf spontaneous fission sources measured in two thermal well counters representative of the type in common use by international inspectorates. Fast accidental sampling was the favored method of acquiring the Feynman-Y data. Our experimental study confirmed the basic functional dependences predicted although experimental results when available are preferred. With an appropriate gate setting Feynman-Y analysis provides an alternative to shift register analysis for safeguards applications which is opening up new avenues of data collection and data reduction to explore.

  8. Determination of optimum processing temperature for transformation of glyceryl monostearate.

    Science.gov (United States)

    Yajima, Toshio; Itai, Shigeru; Takeuchi, Hirofumi; Kawashima, Yoshiaki

    2002-11-01

    The purpose of this study was to clarify the mechanism of transformation from alpha-form to beta-form via beta'-form of glyceryl monostearate (GM) and to determine the optimum conditions of heat-treatment for physically stabilizing GM in a pharmaceutical formulation. Thermal analysis repeated twice using a differential scanning calorimeter (DSC) were performed on mixtures of two crystal forms. In the first run (enthalpy of melting: DeltaH1), two endothermic peaks of alpha-form and beta-form were observed. However, in the second run (enthalpy of melting: DeltaH2), only the endothermic peak of the alpha-form was observed. From a strong correlation observed between the beta-form content in the mixture of alpha-form and beta-form and the enthalpy change, (DeltaH1-DeltaH2)/DeltaH2, beta-form content was expressed as a function of the enthalpy change. Using this relation, the stable beta-form content during the heat-treatment could be determined, and the maximum beta-form content was obtained when the heat-treatment was carried out at 50 degrees C. An inflection point existed in the time course of transformation of alpha-form to beta-form. It was assumed that almost all of alpha-form transformed to beta'-form at this point, and that subsequently only transformation from beta'-form to beta-form occurred. Based on this aspect, the transformation rate equations were derived as consecutive reaction. Experimental data coincided well with the theoretical curve. In conclusion, GM was transformed in the consecutive reaction, and 50 degrees C was the optimum heat-treatment temperature for transforming GM from the alpha-form to the stable beta-form.

  9. The Optimum Level of Sevoflurane in Pediatric Echocardiography.

    Science.gov (United States)

    Conghai, Fan; Fengchao, Zhang; Chengjing, Shan; Cheng, Wen; Yunji, Wang; Xiaobo, Li

    2015-11-01

    Sevoflurane is shown to be safe and effective in pediatric echocardiography. This study explores the optimum level in pediatric echocardiography. One hundred and twenty children, with an age range of 35 days-3 years, were included in this study. The children with severe cyanotic congenital heart disease or severe pneumonia, which was Grade I or II according to the American College of Physicians Guideline Grading, were excluded. All children received the anesthesia with sevoflurane. The inhalation anesthesia level decreased from 2.5 to 1.0 %, with a decrement of 0.5 %. The induction time (T0), echocardiography time (T1), and time to awakening (T2) in each child were recorded, and the changes in the blood pressure, heart rate, breath, and oxygen saturation in each child were also monitored. The Ramsay scale scoring during anesthesia and the case number of failure in echocardiography in each group were also recorded. When the level of sevoflurane inhalation was maintained at 1.0 %, the childrens' scores were low, including 8 incompliant children, and p sevoflurane inhalation level increased. When the sevoflurane inhalation increased to 1.5 %, the children could sleep with stable blood pressure, and no dysphoria occurred during the echocardiography. When the sevoflurane inhalation level increased to 2.5 %, the Ramsay scores did not increase. However, the T2 significantly increased (p blood pressure and heart rate in each group did not change significantly. With the premise of safety and efficacy in children, the optimum level of sevoflurane in pediatric echocardiography was 1.5-2.0 %.

  10. Application of non-toxic phytic acid in metal protection%植酸在金属防腐中的应用研究

    Institute of Scientific and Technical Information of China (English)

    刘泓; 沈月敏

    2009-01-01

    用失重法研究了植酸对金属的阻蚀性.分别以0.1 mol/L HCl、0.1 mol/L NaCl或0.1 mol/L NaOH为介质,配置不同植酸浓度的 (空白自来水,0.5%,1%,1.5%,2%)溶液,并与相同介质下1.5%亚硝酸钠或1.5%磷酸二氢锌的溶液相比较.实验表明,对于铝、锌和铁三种金属,植酸对铝的防腐率最为显著,其中尤以植酸在NaCl介质中对铝的防腐性能最优,最佳防腐浓度为0.5%;对于锌、铁,防腐作用最佳的是空白自来水介质的1.5%磷酸二氢锌钝化液.%The application of phytic acid in metal protection was researched by weight-loss method.Using 0.1 mol/L HCl,0.1 mol/L NaCl or 0.1 mol/L NaOH respectively as the medium,different concentrations of phytic acid(blank water,0.5%,1%,1.5%,2%) were prepared,compared with the solution of 1.5% NaNO2 or 1.5% Zn(H_2PO_4)_2.The result of the experiment is as follows:for Al, Zn and Fe,the corrosion rate of phytic acid to Al is the best,and its best media is NaCl,the best concentration is 0.5%.For Zn and Fe,its best media is 1.5% Zn(H_2PO_4)_2 of blank water.

  11. Effects of UV-B radiation on microcystin production of a toxic strain of Microcystis aeruginosa and its competitiveness against a non-toxic strain

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Zhen, E-mail: zhyang@niglas.ac.cn; Kong, Fanxiang, E-mail: fxkong@niglas.ac.cn; Shi, Xiaoli; Yu, Yang; Zhang, Min

    2015-02-11

    Highlights: • UV-B radiation showed higher inhibition to non-toxin producing than toxin-producing strains on growth and photosynthetic activity. • Both intracellular and extracellular MC contents decreased markedly under UV-B radiation. • Higher resistance to UV-B radiation helped toxin-producing M. aeruginosa to predominate in the competition. - Abstract: Microcystins (MCs) produced by toxic cyanobacteria pose a health hazard to humans and animals. Some environmental factors can alter the MC concentrations by affecting the abundance of toxin-producing strains in a cyanobacteria population and/or their toxin production. In this study, we designed a monoculture and competition experiment to investigate the impacts of UV-B radiation on MC production and the competition between toxin and non-toxin producing strains of Microcystis aeruginosa. UV-B radiation resulted in higher inhibition of the growth and photosynthetic activity of the non-toxin producing strain relative to that observed for the toxin-producing strain. Both intracellular and extracellular MC contents decreased markedly when the toxin-producing strain was exposed to UV-B radiation. In addition, a quantitative real-time PCR assay revealed that the ratio of toxin-producing M. aeruginosa under UV-B exposure was higher than that under PAR alone at an early stage of the experiment. However, its abundance under UV-B exposure was lower compared with the PAR alone treatment after day 12. Our study demonstrated that UV-B radiation has a great impact on the abundance of the toxin-producing strain in the Microcystis population and their toxin production, which suggests that the fluctuation of UV-B radiation affects the MC level of cyanobacteria blooms.

  12. Separation, concentration and determination of chloramphenicol in environment and food using an ionic liquid/salt aqueous two-phase flotation system coupled with high-performance liquid chromatography.

    Science.gov (United States)

    Han, Juan; Wang, Yun; Yu, Cuilan; Li, Chunxiang; Yan, Yongsheng; Liu, Yan; Wang, Liang

    2011-01-31

    Ionic liquid-salt aqueous two-phase flotation (ILATPF) is a novel, green, non-toxic and sensitive samples pretreatment technique. ILATPF coupled with high-performance liquid chromatography (HPLC) was developed for the analysis of chloramphenicol, which combines ionic liquid aqueous two-phase system (ILATPS) based on imidazolium ionic liquid (1-butyl-3-methylimidazolium chloride, [C(4)mim]Cl) and inorganic salt (K(2)HPO(4)) with solvent sublation. In ILATPF systems, phase behaviors of the ILATPF were studied for different types of ionic liquids and salts. The sublation efficiency of chloramphenicol in [C(4)mim]Cl-K(2)HPO(4) ILATPF was influenced by the types of salts, concentration of K(2)HPO(4) in aqueous solution, solution pH, nitrogen flow rate, sublation time and the amount of [C(4)mim]Cl. Under the optimum conditions, the average sublation efficiency is up to 98.5%. The mechanism of ILATPF contains two principal processes. One is the mechanism of IL-salt ILATPS formation, the other is solvent sublation. This method was practical when applied to the analysis of chloramphenicol in lake water, feed water, milk, and honey samples with the linear range of 0.5-500 ng mL(-1). The method yielded limit of detection (LOD) of 0.1 ng mL(-1) and limit of quantification (LOQ) of 0.3 ng mL(-1). The recovery of CAP was 97.1-101.9% from aqueous samples of environmental and food samples by the proposed method. Compared with liquid-liquid extraction, solvent sublation and ionic liquid aqueous two-phase extraction, ILATPF can not only separate and concentrate chloramphenicol with high sublation efficiency, but also efficiently reduce the wastage of IL. This novel technique is much simpler and more environmentally friendly and is suggested to have important applications for the concentration and separation of other small biomolecules.

  13. Multi-Objective Fuzzy Optimum Design Based on Reliability for Offshore Jacket Platforms

    Institute of Scientific and Technical Information of China (English)

    康海贵; 刘未; 翟钢军; 徐发淙; 封盛

    2001-01-01

    In consideration of the fuzzy constraint boundary and through analysis of structural reliability, a model of structural fuzzy optimum design is established based on reliability for offshore jacket platforms. According to the characteristics of offshore jacket platforms, the tolerance coefficient of the constraint boundary is determined with the fuzzy optimization method. The optimum level cut set λ *, which is the intersection of the fuzzy constraint set and fuzzy objective set, is determined with the bound search method, and then the fuzzy optimum solution to the fuzzy optimization problem is obtained. The central offshore platform SZ36-1 is designed with the fuzzy optimum model based on reliability; the results are compared with those from deterministic optimum design and fuzzy optimum design. The tendency of design variables in the above three methods and its reasons are analyzed. The results of an example show that the fuzzy optimum design based on reliability is stable and reliable.

  14. The optimum measurement precision evaluation for blood components using near-infrared spectra on 1000-2500 nm

    Science.gov (United States)

    Zhang, Ziyang; Sun, Di; Han, Tongshuai; Guo, Chao; Liu, Jin

    2016-10-01

    In the non-invasive blood components measurement using near infrared spectroscopy, the useful signals caused by the concentration variation in the interested components, such as glucose, hemoglobin, albumin etc., are relative weak. Then the signals may be greatly disturbed by a lot of noises in various ways. We improved the signals by using the optimum path-length for the used wavelength to get a maximum variation of transmitted light intensity when the concentration of a component varies. And after the path-length optimization for every wavelength in 1000-2500 nm, we present the detection limits for the components, including glucose, hemoglobin and albumin, when measuring them in a tissue phantom. The evaluated detection limits could be the best reachable precision level since it assumed the measurement uses a high signal-to-noise ratio (SNR) signal and the optimum path-length. From the results, available wavelengths in 1000-2500 nm for the three component measurements can be screened by comparing their detection limit values with their measurement limit requirements. For other blood components measurement, the evaluation their detection limits could also be designed using the method proposed in this paper. Moreover, we use an equation to estimate the absorbance at the optimum path-length for every wavelength in 1000-2500 nm caused by the three components. It could be an easy way to realize the evaluation because adjusting the sample cell's size to the precise path-length value for every wavelength is not necessary. This equation could also be referred to other blood components measurement using the optimum path-length for every used wavelength.

  15. Optimum conditions for prebiotic evolution in extraterrestrial environments

    Science.gov (United States)

    Abbas, Ousama H.

    The overall goal of the dissertation was to devise synthetic pathways leading to the production of peptides and amino acids from smaller organic precursors. To this end, eight different zeolites were tested in order to determine their catalytic potential in the conversion of amino acids to peptides. The zeolites tested were either synthetic or naturally occurring. Acidic solutions of amino acids were prepared with or without zeolites and their reactivity was monitored over a four-week time interval. The kinetics and feasibility of peptide synthesis from selected amino acid combinations was investigated via the paper chromatography technique. Nine different amino acids were tested. The nature and extent of product were measured at constant time intervals. It was found that two ZSM-5 synthetic zeolites as well as the Fisher Scientific zeolite mix without alumina salts may have a catalytic potential in the conversion of amino acids to peptides. The conversion was verified by matching the paper chromatogram of the experimental product with that of a known peptide. The experimental results demonstrate that the optimum solvent system for paper chromatographic analysis of the zeolite-catalyzed self-assembly of the amino acids L-aspartic acid, L- asparagine, L-histidine, and L-serine is a 50:50 mixture of 1-butanol and acetone by volume. For the amino acids L-alanine, L-glycine, and L-valine, the optimum solvent was found to be a 30:70 mixture of ammonia and propanol by volume. A mathematical model describing the distance traveled (spot position) versus reaction time was constructed for the zeolite-catalyzed conversion of L- leucine and L-tyrosine and was found to approximately follow the function f(t) = 25 ln t. Two case studies for prebiotic synthesis leading to the production of amino acids or peptides in extraterrestrial environments were discussed: one involving Saturn's moon Titan, and the other involving Jupiter's moon Europa. In the Titan study, it was determined

  16. Determination of Optimum Cross-section for Oran Highway Revetment

    Science.gov (United States)

    Velioglu, Deniz; Sogut, Erdinc; Guler, Isikhan

    2017-04-01

    Revetments are shore parallel, sloping coastal structures which are built to provide protection from the negative effects of the sea. The revetment mentioned in this study is located in the City of Oran, Algeria and is currently under construction. This study investigates the determination of the optimum revetment cross section for Oran highway, considering both the hydraulic stability of the revetment and economy. The existence of cliffs in the region and the settlement of the City of Oran created a necessity to re-align Oran highway; therefore, it was shifted towards the Gulf of Oran. Approximately 1 km of the highway is to be constructed on the Mediterranean Sea due to the new alignment. In order to protect the sea side of the road from the adverse effects of the sea, a revetment was designed. The proposed cross section had an armour layer composed of 23 tons of antifer units and regular placement of armour units was recommended. In order to check the hydraulic stability of the proposed section, physical model tests were performed in the laboratory of LEM (Laboratoire d'Etudes Maritimes) in Algeria, using the pre-determined design wave conditions. The physical model tests revealed that the trunk of the revetment was totaly damaged. Accordingly, the proposed section was found insufficient and certain modifications were required. The first modification was made in the arrangement of armour units, changing them from regular to irregular. After testing the new cross section, it was observed that the revetment was vulnerable to breaking wave attack due to the toe geometry and thus the toe of the revetment had to be re-shaped. Therefore, the second option was to reduce the toe elevation. It was observed that even though the revetment trunk was safe, the damage in the toe was not in acceptable limits. The new cross section was found insufficient and as the final option, the weight of the antifer units used in the armour layer was increased, the toe length of the

  17. Optimum Construction of Heating Coil for Domestic Induction Cooker

    Science.gov (United States)

    Sinha, Dola; Bandyopadhyay, Atanu; Sadhu, Pradip Kumar; Pal, Nitai

    2010-10-01

    The design and optimization of the parameters of heating coil is very important for the analytical analysis of high frequency inverter fed induction cooker. Moreover, accurate prediction of high frequency winding loss (i.e., losses due to skin and proximity effects) is necessary as the induction cooker used in power electronics applications. At high frequency current penetration in the induction coil circuit is very difficult for conducting wire due to skin-effect. To eradicate the skin effect heating coil is made up of bundle conductor i.e., litz wire. In this paper inductances and AC resistances of a litz-wire are calculated and optimized by considering the input parameters like wire type, shape, number of strand, number of spiral turn, number of twist per feet of heating coil and operating frequency. A high frequency half bridge series resonant mirror inverter circuit is used in this paper and taking the optimum values of inductance and ac resistance the circuit is simulated through PSPICE simulations. It has been noticed that the results are feasible enough for real implementation.

  18. Optimum Heart Rate to Minimize Pulsatile External Cardiac Power

    Science.gov (United States)

    Pahlevan, Niema; Gharib, Morteza

    2011-11-01

    The workload on the left ventricle is composed of steady and pulsatile components. Clinical investigations have confirmed that an abnormal pulsatile load plays an important role in the pathogenesis of left ventricular hypertrophy (LVH) and progression of LVH to congestive heart failure (CHF). The pulsatile load is the result of the complex dynamics of wave propagation and reflection in the compliant arterial vasculature. We hypothesize that aortic waves can be optimized to reduce the left ventricular (LV) pulsatile load. We used an in-vitro experimental approach to investigate our hypothesis. A unique hydraulic model was used for in-vitro experiments. This model has physical and dynamical properties similar to the heart-aorta system. Different compliant models of the artificial aorta were used to test the hypothesis under various aortic rigidities. Our results indicate that: i) there is an optimum heart rate that minimizes LV pulsatile power (this is in agreement with our previous computational study); ii) introducing an extra reflection site at the specific location along the aorta creates constructive wave conditions that reduce the LV pulsatile power.

  19. Optimum Resource Allocation and Eliminating Waste Inside Food Industry

    Directory of Open Access Journals (Sweden)

    Chandru Nagarajan Sathiyabama

    2013-06-01

    Full Text Available This article seeks to allocate optimum resources for wrapping section and suggesting a suitable method that need to be in place for successful elimination of waste inside the food industry wrapping section. It also includes identifying the main reasons for various types of wastages inside wrapping section and cost of all the wastages. The paper is based on the observation and research using the approach of lean tools and techniques. The methodology used for evaluating data is value stream mapping and some statistical SPSS tools for analysis. Data’s are real and are gathered from three different production shifts inside a food industry wrapping section. The main reasons for wastages inside the wrapping section are highlighted. Finally, the paper was concluded by estimating total cost of wastages and recommended suitable way to save the wastage costs. The need of change of jaws inside the wrapping machines, regular maintenance of all machines throughout the industry and training the personnel are recommended. The possible methods along with its benefits to reduce waste, operators, improve productivity and business growth was also highlighted.

  20. Optimum Binary Search Trees on the Hierarchical Memory Model

    CERN Document Server

    Thite, Shripad

    2008-01-01

    The Hierarchical Memory Model (HMM) of computation is similar to the standard Random Access Machine (RAM) model except that the HMM has a non-uniform memory organized in a hierarchy of levels numbered 1 through h. The cost of accessing a memory location increases with the level number, and accesses to memory locations belonging to the same level cost the same. Formally, the cost of a single access to the memory location at address a is given by m(a), where m: N -> N is the memory cost function, and the h distinct values of m model the different levels of the memory hierarchy. We study the problem of constructing and storing a binary search tree (BST) of minimum cost, over a set of keys, with probabilities for successful and unsuccessful searches, on the HMM with an arbitrary number of memory levels, and for the special case h=2. While the problem of constructing optimum binary search trees has been well studied for the standard RAM model, the additional parameter m for the HMM increases the combinatorial comp...

  1. Determining optimum climate drivers for weather risk projections

    Science.gov (United States)

    Chavez, Erik; Kilian, Markus; Lucarini, Valerio

    2016-04-01

    In spite of the exponential increase of available data, the uncertainties of projections of weather variability, especially at local scale, have not decreased. This poses important challenges for the design of weather risk management strategies in various vulnerable sectors such as energy or agricultural production. This paper focuses on a two step methodology to enable projection of local weather risk in future climate scenarios. First, we focus on the optimum selection of drivers of regional weather patterns in order to project local weather variability risk estimates in future climate scenarios. This is carried out through the use of stochastic downscaling enabling conditional modelling of pixel-level distributions of weather variables as a function of inter-annual and inter-decadal climate variability drivers. Secondly, a statistical and physically-based climate model selection methodology is developed in order to produce a sub-ensemble of inter-annual and decadal variability drivers dataset that allows accurate and robust projection of weather variability. The case study of South Eastern Africa will be used. Datasets retrieved from CMIP5 repository in three RCP scenarios (historical, 8.5 and 2.5) are used as well as observed historical weather data.

  2. Optimum modulation and demodulation matrices for solar polarimetry.

    Science.gov (United States)

    del Toro Iniesta, J C; Collados, M

    2000-04-01

    Both temporal and/or spatial modulation are mandatory in current solar polarimetry [Appl. Opt. 24, 3893 (1985); 26, 3838 (1987)]. The modulating and demodulating processes are mathematically described by matrices O and D, respectively, on whose structure the accuracy of Stokes parameter measurements depend. We demonstrate, based on the definition of polarimetric efficiency [Instituto de Astrofísica de Canarias Internal Report (1994); ASP Conf. Ser. 184, 3 (1999)], that the maximum efficiencies of an ideal polarimeter are unity for Stokes I and for (Q(2) + U(2) + V(2))(1/2) and that this occurs if and only if O(T)O is diagonal; given a general (possibly nonideal) modulation matrix O, the optimum demodulation matrix turns out to be D = (O(T)O)(-1)O(T); and the maximum efficiencies in the nonideal case are given by the rms value of the column elements of matrix O and are reached by modulation matrices such that O(T)O is diagonal. From these analytical results we distill two recipes useful in the practical design of polarimeters. Their usefulness is illustrated by discussing cases of currently available solar polarimeters. Although specifically devoted to solar polarimetry, the results here may be applied in practically all other branches of science for which polarimetric measurements are needed.

  3. Optimum and equilibrium in a transport problem with queue effects

    CERN Document Server

    Crippa, Gianluca; Pratelli, Aldo

    2008-01-01

    Consider a distribution of citizens in an urban area in which some services (supermarkets, post offices...) are present. Each citizen, in order to use a service, spends an amount of time which is due both to the travel time to the service and to the queue time waiting in the service. The choice of the service to be used is made by every citizen in order to be served more quickly. Two types of problems can be considered: a global optimization of the total time spent by the citizens of the whole city (we define a global optimum and we study it with techniques from optimal mass transportation) and an individual optimization, in which each citizen chooses the service trying to minimize just his own time expense (we define the concept of equilibrium and we study it with techniques from game theory). In this framework we are also able to exhibit two time-dependent strategies (based on the notions of prudence and memory respectively) which converge to the equilibrium.

  4. Optimum viscous flow in pressure-swirl atomizers

    Science.gov (United States)

    Amini, Ghobad; Pereira, Aaron; Yun, Sangsig; Li, Xianguo

    2013-11-01

    Due to their simple configuration and reliable operation, pressure-swirl atomizers are widely used in applications such as combustion, painting, humidification, and sprinkling. The liquid is swirled by entering into the atomizer tangentially and its surface area is increased as discharges in a large spray angle. Understanding the effects of nozzle geometry and inlet flow condition on the discharge coefficient and spray angle is very important in nozzle design. To this end, the flow field inside a pressure-swirl atomizer has been studied theoretically. The main body of the liquid is taken to be moving in circles round the axis. Within the boundary layer, containing transverse and longitudinal velocity components, the retarded liquid is slowed down by viscosity and driven towards the exit orifice by pressure gradient. The swirling motion of liquid creates a low pressure zone near the nozzle axis and leads to the formation of a helical air-core. Through studying the growth of the boundary layer from nozzle entry to the orifice exit, the portions of the outflow exits the orifice from boundary layer current and also from the main body of the swirling liquid are specified. For a given range of pressure drop values, the optimum nozzle geometry and liquid flowrate are predicted. Additionally, the reason of increasing the flow by increasing liquid viscosity or decreasing orifice diameter is explained. A series of experiments and numerical modeling have also been carried out to support the theoretical results.

  5. Analysis of optimum density of forest roads in rural properties

    Directory of Open Access Journals (Sweden)

    Flávio Cipriano de Assis do Carmo

    2013-09-01

    Full Text Available This study analyzed the density of roads in rural properties in the south of the Espírito Santo and compared it with the calculation of the optimal density in forestry companies in steep areas. The work was carried out in six small rural properties based on the costs of roads of forest use, wood extraction and the costs of loss of productive area. The technical analysis included time and movement study and productivity. The economic analysis included operational costs, production costs and returns for different scenarios of productivity (180m.ha-1, 220m.ha-1and 250 m.ha-1. According to the results, all the properties have densities of road well above the optimum, which reflects the lack of criteria in the planning of the forest stands, resulting in a inadequate use of plantation area. Property 1 had the highest density of roads (373.92 m.ha-1 and the property 5 presented the lowest density (111.56 m.ha-1.

  6. Determination of Optimum Compression Ratio: A Tribological Aspect

    Directory of Open Access Journals (Sweden)

    L. Yüksek

    2013-12-01

    Full Text Available Internal combustion engines are the primary energy conversion machines both in industry and transportation. Modern technologies are being implemented to engines to fulfill today's low fuel consumption demand. Friction energy consumed by the rubbing parts of the engines are becoming an important parameter for higher fuel efficiency. Rate of friction loss is primarily affected by sliding speed and the load acting upon rubbing surfaces. Compression ratio is the main parameter that increases the peak cylinder pressure and hence normal load on components. Aim of this study is to investigate the effect of compression ratio on total friction loss of a diesel engine. A variable compression ratio diesel engine was operated at four different compression ratios which were "12.96", "15:59", "18:03", "20:17". Brake power and speed was kept constant at predefined value while measuring the in- cylinder pressure. Friction mean effective pressure ( FMEP data were obtained from the in cylinder pressure curves for each compression ratio. Ratio of friction power to indicated power of the engine was increased from 22.83% to 37.06% with varying compression ratio from 12.96 to 20:17. Considering the thermal efficiency , FMEP and maximum in- cylinder pressure optimum compression ratio interval of the test engine was determined as 18.8 ÷ 19.6.

  7. Optimum Path Synthesis of a Geared Five-Bar Mechanism

    Directory of Open Access Journals (Sweden)

    Wen-Yi Lin

    2013-01-01

    Full Text Available Most studies on path synthesis problems are to trace simple or smooth trajectories. In this work, an optimum synthesis for several special trajectories generated by a geared five-bar mechanism is studied using the one-phase synthesis method. The synthesis problem for the special trajectories, which is originally studied using the two-phase synthesis method discussed in the literature, is a real challenge due to very few dimensionally proportioned mechanisms that can generate the special trajectories. The challenging special trajectories with up to 41 discrete points include a self-overlapping curve, nonsmooth curves with straight segments and vertices, and sophisticated shapes. The error function of the square deviation of positions is used as the objective function and the GA-DE evolutionary algorithm is used to solve the optimization problems. Findings show that the proposed method can obtain approximately matched trajectories at the cost of a tremendous number of evaluations of the objective function. Therefore, the challenging problems may serve as the benchmark problems to test the effectiveness and efficiency of synthesis methods and/or optimization algorithms. All the synthesized solutions have been validated using the animation of the SolidWorks assembly so that the obtained mechanisms are sound and usable.

  8. Design and Construction of an Optimum Wave Flume

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Khalilabadi

    2012-01-01

    Full Text Available This paper describes the design, construction, and testing of a small wave flume and associated equipment. The wave flume is equipped with a flap-type wave generator, capable of producing both regular and irregular waves. Flap paddle is used to examine deep water and floating structures. Instrumentation includes three capacitive wave gauges. The wave-maker is controlled by a desktop computer, which also provides data-logging capability. In order to design a wave absorber of restricted length, all the different mechanisms able to dissipate wave energy studied. Finally from the survey of the wave absorbers used in different laboratories, a gravel beach designed for absorbing the waves coming from wave maker. By sealing leaks around paddle the error of measuring height-to-stroke ratios versus relative depth is decreased by 3%. The main advantage of this system over the previous ones is reduction of the amount of effort in the set up with optimum deflection and low level cost utility.

  9. Optimum airspace design with air traffic controller workload-based partitioning

    Science.gov (United States)

    Yousefi, Arash

    This dissertation proposes an Air Traffic Controller (ATC) workload based methodology for optimum airspace partitioning. Initially, we define a set of airspace metrics for analytical modeling of the ATC cognitive workload and airspace complexity. We use a large-scale, fast-time simulation to model the current sectors in five Air Route Traffic Control Centers (ARTCCs) and compute the airspace metrics for each sector. These metrics are then used to calculate ATC workload and traffic complexity during various time intervals. Sectors are then ranked based on their traffic complexity and we show that the defined metrics are able to identify the complex sectors. Having a reasonable ATC workload modeling technique, we decompose the U.S. national airspace into three layers using altitude ranges based on operational levels of low, high, and ultra-high airspace. Each layer is further tiled into 2,566 hexagonal cells (hex-cells) with 24 nautical mile sides. These hex-cells are assumed to be finite elements of airspace and ATC workload is modeled for each hex-cell using various airspace metrics. We apply visualization techniques to analyze the spatial and temporal distribution of the controller workload and to identify congested periods of the U.S. National Airspace System (NAS). Having the workload values for each hex-cell during the congested periods, we develop clustering algorithms using optimization theory to cluster hex-cells and partition the airspace to ARTCCs and sectors. We first partition the airspace to ARTCCs and define the optimum boundaries for different number of ARTCCs. Then the partitioning is continued within each ARTCC to construct optimum sector boundaries. This dissertation concentrates on simulation as a means to evaluate cognitive workload for the elements of airspace regardless of current sector and ARTCC boundaries. The only apriori inputs are the location of current ARTCC facilities and airports, the demand profiles for each city pair, and the filed

  10. Amelioration of Acute Mercury Toxicity by a Novel, Non-Toxic Lipid Soluble Chelator N,N'bis-(2-mercaptoethyl)isophthalamide: Effect on Animal Survival, Health, Mercury Excretion and Organ Accumulation.

    Science.gov (United States)

    Clarke, David; Buchanan, Roger; Gupta, Niladri; Haley, Boyd

    2012-01-01

    The toxic effects of mercury are known to be complex with specific enzyme inhibitions and subsequent oxidative stress adding to the damaging effects. There are likely other factors involved, such as the development of impaired metal ion homeostasis and depletion of thiol and selenium based metabolites such as cysteine and selenium. Much of the toxicity of mercury occurs at the intracellular level via binding of Hg(2+) to thiol groups in specific proteins. Therefore, amelioration of mercury toxicity by the use of chelation would likely be enhanced by the use of a chelator that could cross the cell membrane and the blood brain barrier. It would be most favorable if this compound was of low toxicity, had appropriate pharmacokinetics, bound and rendered mercury cation non-toxic and had antioxidant properties. Herein we report on such a chelator, N,N'-bis(2-mercaptoethyl)isophthalamide (NBMI), and, using an animal model, show that it prevented the toxic effects associated with acute exposure induced by injected mercury chloride.

  11. Relative quantification of PIK3CA gene expression level in fine-needle aspiration biopsy thyroid specimens collected from patients with papillary thyroid carcinoma and non-toxic goitre by real-time RT-PCR

    Directory of Open Access Journals (Sweden)

    Wojciechowska-Durczyńska Katarzyna

    2010-08-01

    Full Text Available Abstract Background Recent studies have shown that the phosphatidylinositol 3-kinase (PI3K signaling pathway is important regulator of many cellular events, including apoptosis, proliferation and motility. PI3K pathway alterations (PIK3CA gene mutations and/or amplification have been observed in various human tumours. In the majority of diagnosed cases, mutations are localized in one of the three "hot spots" in the gene, responsible for coding catalytic subunit α of class I PI3K (PIK3CA. Mutations and amplification of PIK3CA gene are characteristic for thyroid cancer, as well. Methods The aim of our study was to examine a gene expression level of PIK3CA in fine-needle aspiration biopsy (FNAB thyroid specimens in two types of thyroid lesions, papillary thyroid carcinoma (PTC and non-toxic goitre (NTG. Following conventional cytological examination, 42 thyroid FNAB specimens, received from patients with PTC (n = 20 and NTG (n = 22, were quantitatively evaluated regarding PIK3CA expression level by real-time PCR in the ABI PRISM® 7500 Sequence Detection System. Results Significantly higher expression level (RQ of PIK3CA in PTC group has been noted in comparison with NTG group (p Conclusion These observations may suggest role of PIK3CA alterations in PTC carcinogenesis.

  12. Optimum design of Cassegrain antenna for space laser communication

    Science.gov (United States)

    Hu, Yuan; Jiang, Lun; Wang, Chao; Li, Yingchao

    2016-10-01

    The divergence angle is very important index in space laser communication for energy transfer. Typically, the large aperture telescope as optical antenna is used for angle compression, and the divergence angle of communication beam is usually calculated by diffraction limit angle equation 1.22λ/D. This equation expresses the diffraction of a spherical wave through a circular aperture. However, the light source commonly used laser with a Gaussian distribution, and the optical antenna is central obscurations. The antenna parameters which is obscuration ratio and Gaussian beam apodization were significantly relative with the far field energy. In this study, we obtain the mathematic relation between the divergence angle, energy loss and the antenna parameters. From the relationship, we know that the divergence angle smaller as the increase of antenna obscuration ratio. It would tend to enhance the far-field energy density. But a larger obscuration ratio will increase the energy loss. At the same time, the increase of Gaussian beam apodization resulted in the energy of first diffraction ring was raised but the radius of first ring was increased. They were conflict. And then, the antenna parameters of trade-off was found from curves of obscuration ratio and curves of divergence angle. The parameters of a Cassegrain antenna was optimum designed for the energy maximization, and considerd the apodization from mechanical structure blocking. The long-distance laser communications were successful in these airborne tests. Stable communication was demonstrated. The energy gain is sufficient for SNR of high-bandwidth transmission in atmospheric channel.

  13. Optimum on-time duty cycle for micropulse technology.

    Science.gov (United States)

    Kirk, Kevin R; Ronquillo, Cecinio; Jensen, Jason D; Zaugg, Brian; Barlow, William R; Stagg, Brian C; Pettey, Jeff H; Olson, Randall J

    2014-09-01

    To evaluate the optimum on time for the most efficient removal of lens fragments using micropulsed ultrasound (US). John A. Moran Eye Center Laboratories, University of Utah, Salt Lake City, Utah, USA. Experimental study. Twenty porcine lens nuclei were soaked in formalin for 2 hours and then divided into 2.0 mm cubes. Using an US machine with a 0.9 mm bent and a 30-degree bevel tip, the on time was varied every millisecond (ms) from 2 ms to 10 ms with the off time kept constant at 10 ms. Efficiency (time to lens removal) and chatter (number of lens fragment repulsions from the tip) were determined. The most efficient phacoemulsification was achieved with an on time of 6 ms. On times shorter than 6 ms were significantly less efficient (R2=.82, P=.04). Greater on times did not result in a significant difference in efficiency (R2=.03, P=.78) but did appear to have more chatter events when comparing 9 to 10 ms with 2 to 8 ms (P<.0001). With micropulsed longitudinal US, a 6 ms on time was equally as efficient as longer on times, while shorter on times (2 to 5 ms) had decreased efficiency. At 9 ms and 10 ms on time, significantly more chatter was noted. Therefore, to maximize phacoemulsification, an on-time setting of 6 ms is recommended. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2014 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  14. Optimum Combined Lenses for Confocal Biochip Scanning System

    Institute of Scientific and Technical Information of China (English)

    黄国亮; 程京; 周玉祥; 冯继宏; 刘诚迅; 金国藩; 邬敏贤; 严瑛白; 张腾飞; 李林

    2002-01-01

    Laboratory-on-a-chip technology has attracted wide interest in recent years, where the sample preparation, bio-chemical reaction, separation, detection and analysis are performed in a small biochip of the size of a fingernail. To obtain a high detection sensitivity of 1 fluors/μm2 (one fluorescence molecule per square micrometer) in biochip scanning systems, the scanning objective lens is required to have a high numerical aperture (>0.5), very small focal spot (3 mm). This study presents the design of optimum combined lenses including scanning objective and fluorescence focal lenses. The scanning objective had a high numerical aperture (NA) of 0.72, a very small focal spot of 1.67 μm, a long back focal length of 3.2 mm, and a high resolving power of 760 lines/mm. The fluorescence focal lenses had an NA of 0.3, a fluorescence focal spot of 16 μm, a long back focal length of 16.7 mm and a resolving power of 590 lines/mm. The phase aberrations of the combined lenses, including the aspherical aberration and the chromatic aberration corresponding to wavelengths of 532, 570, 635, and 670 nm, were well-corrected. The encircled energy diagram of the lenses was within the diffraction limit. The study also included the focal spot diagram, the optical path difference diagram, the transverse ray fan plot, and the modulation transfer function. A confocal biochip scanning system with designed combined lenses was developed and some experiments were conducted on a multi-channel biochip.

  15. Concentration device

    DEFF Research Database (Denmark)

    2013-01-01

    A concentration device (2) for filter filtration concentration of particles (4) from a volume of a fluid (6). The concentration device (2) comprises a filter (8) configured to filter particles (4) of a predefined size in the volume of the fluid (6). The concentration device (2) comprises...

  16. Modeling Budget Optimum Allocation of Khorasan Razavi Province Agriculture Sector

    Directory of Open Access Journals (Sweden)

    Seyed Mohammad Fahimifard

    2016-09-01

    Full Text Available Introduction: Stock shortage is one of the development impasses in developing countries and trough it the agriculture sector has faced with the most limitation. The share of Iran’s agricultural sector from total investments after the Islamic revolution (1979 has been just 5.5 percent. This fact causes low efficiency in Iran’s agriculture sector. For instance per each 1 cubic meter of water in Iran’s agriculture sector, less that 1 kilogram dry food produced and each Iranian farmer achieves less annual income and has less mechanization in comparison with similar countries in Iran’s 1404 perspective document. Therefore, it is clear that increasing investment in agriculture sector, optimize the budget allocation for this sector is mandatory however has not been adequately and scientifically revised until now. Thus, in this research optimum budget allocation of Iran- Khorasan Razavi province agriculture sector was modeled. Materials and Methods: In order to model the optimum budget allocation of Khorasan Razavi province’s agriculture sector at first optimum budget allocation between agriculture programs was modeled with compounding three indexes: 1. Analyzing the priorities of Khorasan Razavi province’s agriculture sector experts with the application of Analytical Hierarchy Process (AHP, 2. The average share of agriculture sector programs from 4th country’s development program for Khorasan Razavi province’s agriculture sector, and 3.The average share of agriculture sector programs from 5th country’s development program for Khorasan Razavi province’s agriculture sector. Then, using Delphi technique potential indexes of each program was determined. After that, determined potential indexes were weighted using Analytical Hierarchy Process (AHP and finally, using numerical taxonomy model to optimize allocation of the program’s budget between cities based on two scenarios. Required data, also was gathered from the budget and planning

  17. The Effect of Crumb Rubber Particle Size to the Optimum Binder Content for Open Graded Friction Course

    Directory of Open Access Journals (Sweden)

    Mohd Rasdan Ibrahim

    2014-01-01

    Full Text Available The main objective of this paper is to investigate the relations of rubber size, rubber content, and binder content in determination of optimum binder content for open graded friction course (OGFC. Mix gradation type B as specified in Specification for Porous Asphalt produced by the Road Engineering Association of Malaysia (REAM was used in this study. Marshall specimens were prepared with four different sizes of rubber, namely, 20 mesh size [0.841 mm], 40 mesh [0.42 mm], 80 mesh [0.177 mm], and 100 mesh [0.149 mm] with different concentrations of rubberised bitumen (4%, 8%, and 12% and different percentages of binder content (4%–7%. The appropriate optimum binder content is then selected according to the results of the air voids, binder draindown, and abrasion loss test. Test results found that crumb rubber particle size can affect the optimum binder content for OGFC.

  18. Experimental optimum design and luminescence properties of NaY(Gd)(MoO4)2:Er3+ phosphors

    Science.gov (United States)

    Jia-Shi, Sun; Sai, Xu; Shu-Wei, Li; Lin-Lin, Shi; Zi-Hui, Zhai; Bao-Jiu, Chen

    2016-06-01

    Three-factor orthogonal design (OD) of Er3+/Gd3+/T (calcination temperature) is used to optimize the luminescent intensity of NaY(Gd)(MoO4)2:Er3+ phosphor. Firstly, the uniform design (UD) is introduced to explore the doping concentration range of Er3+/Gd3+. Then OD and range analysis are performed based on the results of UD to obtain the primary and secondary sequence and the best combination of Er3+, Gd3+, and T within the experimental range. The optimum sample is prepared by the high temperature solid state method. Photoluminescence excitation and emission spectra of the optimum sample are detected. The intense green emissions (530 nm and 550 nm) are observed which originate from Er3+ 2H11/2→ 4I15/2 and 4S3/2→4I15/2, respectively. Thermal effect is investigated in the optimum NaY(Gd3+)(MoO4)2:Er3+ phosphors, and the green emission intensity decreases as temperature increases. Project supported by Education Reform Fund of Dalian Maritime University, China (Grant No. 2015Y37), the Natural Science Foundation of Liaoning Province, China (Grant Nos. 2015020190 and 2014025010), the Open Fund of the State Key Laboratory on Integrated Optoelectronics, China (Grant No. IOSKL2015KF27), and the Fundamental Research Funds for the Central Universities, China (Grant No. 3132016121).

  19. Optimum dose of 2-hydroxyethyl methacrylate based bonding material on pulp cells toxicity

    Directory of Open Access Journals (Sweden)

    Widya Saraswati

    2010-06-01

    Full Text Available Background: 2-hydroxyethyl methacrylate (HEMA, one type of resins commonly used as bonding base material, is commonly used due to its advantageous chemical characteristics. Several preliminary studies indicated that resin is a material capable to induce damage in dentin-pulp complex. It is necessary to perform further investigation related with its biological safety for hard and soft tissues in oral cavity. Purpose: The author performed an in vitro test to find optimum dose of HEMA resin monomer that may induce toxicity in pulp fibroblast cells. Method: The method of this study was experimental laboratory with post test control group design. Primary cell culture was made from dental pulp fibroblast cells, and was given with HEMA resin bonding material in various concentrations (5 µg/ml–2560 µg/ml, and then subjected to toxicity test (MTT assay. Result: HEMA optimum concentration was 320 µg/ml to induce cytotoxicity in pulp fibroblast cells. Conclusion: The used of HEMA - base bonding material with the concentration of 200 µg/ml may induced pulp fibroblas cell toxicity.Latar belakang: Keberhasilan suatu bahan bonding secara klinis tergantung pada kandungan fisik, kimia dan keamanan secara biologis. HEMA (2-hydroxyethyl methacrylate adalah bahan resin yang paling banyak digunakan karena memiliki sifat fisik-kimia yang baik. Beberapa penelitian pendahuluan menyebutkan bahwa resin merupakan bahan yang mampu menyebabkan gangguan pada kompleks dentin pulpa sehingga perlu dilakukan penelitian lebih lanjut menyangkut segi keamanan secara biologis bagi jaringan keras dan jaringan lunak di rongga mulut. Tujuan: Penelitian ini akan menguji secara in vitro (pada kultur sel fibroblas pulpa gigi untuk mengetahui dosis optimal monomer resin HEMA yang dapat menyebabkan toksisitas pada sel fibroblas pulpa. Metode: Metode penelitian ini adalah eksperimental laboratoris dengan rancangan penelitian post test control group design. Kultur sel primer dibuat dari

  20. Concentrated Ownership

    DEFF Research Database (Denmark)

    Rose, Caspar

    2014-01-01

    , especially minority shareholders. Concentrated ownership is associated with benefits and costs. Concentrated ownership may reduce agency costs by increased monitoring of top management. However, concentrated ownership may also provide dominating owners with private benefits of control.......This entry summarizes the main theoretical contributions and empirical findings in relation to concentrated ownership from a law and economics perspective. The various forms of concentrated ownership are described as well as analyzed from the perspective of the legal protection of investors...

  1. Theoretical Calculation on Optimum Si-doping Content in Boron Carbide Thin Film

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The theoretical expression of the relationship between optimum doping content and crystal structure is presented as well as the preparation methods. By using this expression, the optimum doping content of silicon-doped boron carbide thin film is calculated. The quantitative calculation value is consistent with the experimental results. This theoretical expression is also appropriate to resolve the optimum doping content for other electric materials.

  2. Optimum Peak Current Hysteresis Control for Energy Recovering Converter in CDI Desalination

    Directory of Open Access Journals (Sweden)

    Alberto M. Pernía

    2014-06-01

    Full Text Available Capacitive De-Ionization (CDI is becoming a suitable alternative for desalination. The low cost of the materials required and its reduced energy consumption can be critical factors for developing this technique. CDI technology does not require a high-pressure system and the energy storage capability of CDI cells allows it to be reused in other CDI cells, thus minimizing consumption. The goal of the power stage responsible of the energy recovery is transferring the stored energy from one cell to another with the maximum possible efficiency, thus allowing the desalination process to continue. Assuming hysteresis current control is implemented at the DC/DC (direct current converter, this paper aims to determine the optimum peak current through the inductor in each switching period with a view to maximizing overall efficiency. The geometrical parameters of the desalination cell and the NaCl concentration modify the cell electrical properties. The peak current control of the power stage should be adapted to the cell characteristics so that the efficiency behavior of the whole CDI system can be improved. The mathematical model defined in this paper allows the CDI plant automation using the peak inductor current as control variable, adapting its value to the salt concentration during the desalination process.

  3. Optimum Conditions for the Removal of Cr(VI using Modified Eucalyptus Bark

    Directory of Open Access Journals (Sweden)

    Fenjie Niu

    2014-10-01

    Full Text Available The aims of this study were response surface modeling and optimization of Cr(VI removal from solution using formaldehyde-modified eucalyptus bark. A high removal rate of Cr(VI was achieved under the conditions of low adsorbent dosing quantity and high initial concentration of Cr(VI. Analysis of variance showed a high multiple coefficient of determination (R2=0.9875, adjusted determination coefficient (R2Adj=0.9714, and the good second order regression equation. The initial concentration of Cr(VI was 40.15 mg/L, adsorbent dosing quantity 3.40 g/L, and initial reaction pH 2.78, and the largest removal rate was 99.998% under the optimum reaction conditions. Langmuir and Freundlich isothermal models described well adsorption of Cr(VI by the modified stringy bark. Adsorption kinetics studies showed that the adsorption was controlled by multiple factors, dominated by chemical adsorption. The adsorption was found to be spontaneous and endothermic, with △G0 0, and △S0 > 0. Adsorption of Cr(VI by formaldehyde-modified stringy bark was partly controlled by REDOX reactions. The adsorbents were characterized by SEM and FTIR.

  4. Color removal from textile dyebath effluents in a zeolite fixed bed reactor: determination of optimum process conditions using Taguchi method.

    Science.gov (United States)

    Engin, Ahmet Baki; Ozdemir, Ozgür; Turan, Mustafa; Turan, Abdullah Z

    2008-11-30

    Taguchi method was applied as an experimental design to determine optimum conditions for color removal from textile dyebath house effluents in a zeolite fixed bed reactor. After the parameters were determined to treat real textile wastewater, adsorption experiments were carried out. The breakthrough curves for adsorption studies were constructed under different conditions by plotting the normalized effluent color intensity (C/C(0)) versus time (min) or bed volumes (BV). The chosen experimental parameters and their ranges are: HTAB concentration (C(htab)), 1-7.5 gL(-1); HTAB feeding flowrate (Q(htab)), 0.015-0.075 L min(-1); textile wastewater flowrate (Q(dye)), 0.025-0.050 L min(-1) and zeolite bed height (H(bed)), 25-50 cm, respectively. Mixed orthogonal array L(16) (4(2)x2(2)) for experimental plan and the larger the better response category were selected to determine the optimum conditions. The optimum conditions were found to be as follows: HTAB concentration (C(htab))=1g L(-1), HTAB feeding flowrate (Q(htab))=0.015 L min(-1), textile wastewater flowrate (Q(dye))=0.025 L min(-1) and bed height (H(bed))=50 cm. Under these conditions, the treated wastewater volume reached a maximum while the bed volumes (BV) were about 217. While HTAB concentration, gL(-1) (A); zeolite bed height, cm (D) and wastewater flowrate, L min(-1) (C) were found to be significant parameters, respectively, whereas, HTAB flowrate, L min(-1) (B) was found to be an insignificant parameter.

  5. Color removal from textile dyebath effluents in a zeolite fixed bed reactor: Determination of optimum process conditions using Taguchi method

    Energy Technology Data Exchange (ETDEWEB)

    Engin, Ahmet Baki [Sakarya University, Industrial Engineering Department, 54040 Sakarya (Turkey); Ozdemir, Ozguer [Istanbul Technical University, Environmental Engineering Department, 34469 Istanbul (Turkey); Turan, Mustafa [Istanbul Technical University, Environmental Engineering Department, 34469 Istanbul (Turkey)], E-mail: mturan@ins.itu.edu.tr; Turan, Abdullah Z. [Istanbul Technical University, Chemical and Metallurgical Engineering Department, 34469 Istanbul (Turkey)

    2008-11-30

    Taguchi method was applied as an experimental design to determine optimum conditions for color removal from textile dyebath house effluents in a zeolite fixed bed reactor. After the parameters were determined to treat real textile wastewater, adsorption experiments were carried out. The breakthrough curves for adsorption studies were constructed under different conditions by plotting the normalized effluent color intensity (C/C{sub 0}) versus time (min) or bed volumes (BV). The chosen experimental parameters and their ranges are: HTAB concentration (C{sub htab}), 1-7.5 g L{sup -1}; HTAB feeding flowrate (Q{sub htab}), 0.015-0.075 L min{sup -1}; textile wastewater flowrate (Q{sub dye}), 0.025-0.050 L min{sup -1} and zeolite bed height (H{sub bed}), 25-50 cm, respectively. Mixed orthogonal array L{sub 16} (4{sup 2} x 2{sup 2}) for experimental plan and the larger the better response category were selected to determine the optimum conditions. The optimum conditions were found to be as follows: HTAB concentration (C{sub htab}) = 1 g L{sup -1}, HTAB feeding flowrate (Q{sub htab}) = 0.015 L min{sup -1}, textile wastewater flowrate (Q{sub dye}) = 0.025 L min{sup -1} and bed height (H{sub bed}) = 50 cm. Under these conditions, the treated wastewater volume reached a maximum while the bed volumes (BV) were about 217. While HTAB concentration, g L{sup -1} (A); zeolite bed height, cm (D) and wastewater flowrate, L min{sup -1} (C) were found to be significant parameters, respectively, whereas, HTAB flowrate, L min{sup -1} (B) was found to be an insignificant parameter.

  6. Palynological Investigation of the Holocene Thermal Optimum in New Zealand

    Science.gov (United States)

    Newnham, R. M.; McGlone, M. S.; Wilmshurst, J. M.

    2005-12-01

    It has long been assumed in New Zealand (NZ) that the Holocene Thermal Optimum (HTO) occurred at the beginning of the Holocene. Nearly 40 years ago, Hendy and Wilson pioneered the use of 18O/16O composition of calcite in NZ speleothems to reconstruct past climate and in so doing showed an HTO occurring earlier in NZ than in comparable Northern Hemisphere records (Hendy & Wilson,1968). More recent work on NZ speleothems (Williams et al., 2005) corroborates the concept of an early HTO dated between ca 11.7 and 10.6 ka, but there is no definitive description of the event as a NZ-wide phenomenon, no intensive dating of it, nor temperature quantification. Moreover, there is no firm conclusion as to whether it is registered consistently between different proxies and across NZ regions. Until recently, attempts to quantify past climate change from NZ pollen data have been hindered by failure to demonstrate robust relationships between modern pollen assemblages and climate due, it is thought, to strong anthropogenic modification of natural vegetation patterns and steep climatic gradients (Norton et al., 1986). However, as deforestation commenced only ca 700 years ago, and is unambiguously detected in pollen records from throughout NZ, an almost unique opportunity exists to develop pollen-climate transfer functions using pre-human pollen-vegetation sources. McGlone and Wilmshurst have assembled an extensive (138-site) `modern' pollen database, based on ca 700 yr BP pre-deforestation pollen assemblages from peat and lake cores. This now provides a basis for more secure pollen-climate reconstruction than hitherto has been possible. Statistical modelling of the environmental determinants of patterns in the pre-deforestation pollen database indicates the strongest relationship (r2 > 0.8) is with Mean Annual Temperature (MAT) and suggests that this parameter can be reliably reconstructed, with error estimates, from Late Quaternary NZ pollen profiles. We use this database to

  7. Design Concepts for Optimum Energy Use in HVAC Systems.

    Science.gov (United States)

    Electric Energy Association, New York, NY.

    Much of the innovative work in the design and application of heating, ventilating, and air conditioning (HVAC) systems is concentrated on improving the cost effectiveness of such systems through optimizing energy use. One approach to the problem is to reduce a building's HVAC energy demands by designing it for lower heat gains and losses in the…

  8. Concentration risk

    Directory of Open Access Journals (Sweden)

    Matić Vesna

    2016-01-01

    Full Text Available Concentration risk has been gaining a special dimension in the contemporary financial and economic environment. Financial institutions are exposed to this risk mainly in the field of lending, mostly through their credit activities and concentration of credit portfolios. This refers to the concentration of different exposures within a single risk category (credit risk, market risk, operational risk, liquidity risk.

  9. Treatment of solitary, autonomously-functioning, non-toxic thyroid nodules with I131 Adenema tiroideo autónomo no tóxico tratamiento con I131

    Directory of Open Access Journals (Sweden)

    Federico Uribe Londoño

    1991-03-01

    Full Text Available

    Fifteen euthyroid patients (14 women and 1man with solitary autonomously functioning non-toxic thyroid nodules (AFTN were treated with high doses of I131 (mean 19.2 mCi. Diagnosis was made by I131 thyroid scan and triiodothyronine suppression test. The size of the nodule was determined by thyroid ecography both before and after treatment. Evaluation of thyroid function was performed clinically and by T3 T4 and TSH determinations before therapy and during follow.up. AII patients had complete suppression of the surrounding thyroid parenchyma. Two cases of hypothyroidism were found in the first two years of follow-up. We have no explanation for this fact since extranodular thyroid tissue was suppressed and the patients were receiving oral triiodothyronine during radioidine treatment. The nodules decreasedin size In 9 of 13 patients followed (average decrease 45% and disappeared in other 2. our findings suggest that solitary non-toxic AFTN should be treated with I131 particularly if complete suppression of the surrounding thyroid tissue is found. If complete disappearance of the nodule is considered desirable surgical removal must be performed.

    Se trataron 14 mujeres y un hombre, con adenomas tiroideos solitarios funcionalmente autónomos, no tóxicos, con I131 a una dosis promedio de 19.2 mCi. La gamagrafía tiroidea demostró hipercaptación del nódulo con supresión total del resto de la glándula. El tamaño del nódulo se determinó por medio de ecografía tiroidea antes y después del tratamiento, y su autonomía por la prueba de supresión con triyodotironina. El estado tiroideo se puso de presente clínicamente y por la medición de T3, T 4 y TSH en el plasma, antes de la terapia con el radiofármaco y durante la evolución postratamiento. En dos

  10. The challenge of simulating warmth of the mid-Miocene Climate Optimum in CESM1

    Directory of Open Access Journals (Sweden)

    A. Goldner

    2013-06-01

    Full Text Available The mid-Miocene Climatic Optimum (MMCO is an intriguing climatic period due to its above-modern temperatures in mid-to-high latitudes in the presence of close-to-modern CO2 concentrations. We use the recently released Community Earth System Model (CESM1.0 with a slab ocean to simulate this warm period, incorporating recent Miocene CO2 reconstructions of 400 ppm. We simulate a global mean annual temperature (MAT of 18 °C, ~4 °C above the pre-industrial value, but 4 °C colder than the global Miocene MAT we calculate from climate proxies. Sensitivity tests reveal that the inclusion of a reduced Antarctic ice sheet, eastern equatorial Pacific Ocean temperature anomalies, increased CO2 to 560 ppm, and variations in obliquity only marginally improve model-data agreement. All MMCO simulations have an equator to pole temperature gradient which is at least ~ 10 °C larger than the reconstruction from proxies. The MMCO simulation most comparable to the proxy records requires a CO2 concentration of 800 ppm. Our results illustrate that MMCO warmth is not reproducible using the CESM1.0 forced with CO2 concentrations reconstructed for the Miocene or including various proposed Earth system feedbacks; the remaining discrepancy in the MAT is comparable to that introduced by a CO2 doubling. The models tendency to underestimate proxy derived global MAT and overestimate the equator to pole temperature gradient suggests a major climate problem in the MMCO akin to those in the Eocene. Our results imply that this latest model, as with previous generations of climate models, is either not sensitive enough or additional forcings remain missing that explain half of the anomalous warmth and pronounced polar amplification of the MMCO.

  11. Postmortem distribution of guaifenesin concentrations reveals a lack of potential for redistribution.

    Science.gov (United States)

    McIntyre, Iain M; Navarrete, Aylmer; Mena, Othon

    2014-12-01

    Therapeutic (or non-toxic) postmortem guaifenesin blood and liver concentrations have not been previously described. Peripheral blood guaifenesin concentrations were compared to central blood and liver concentrations in eight medical examiner cases. Specimens were initially screened for alcohol and simple volatiles, drugs of abuse, alkaline, and acid/neutral drugs. Guaifenesin, when detected by the acid/neutral drug screen, was subsequently confirmed and quantified by a high performance liquid chromatography procedure. Data suggest that postmortem guaifenesin peripheral blood concentrations may be considered non-toxic to at least 5.4mg/L with liver concentrations to at least 7.0mg/kg. Overall, guaifenesin concentrations ranged from 1.9 to 40mg/L in peripheral blood, 2.2-150mg/L in central blood, and 2.6-36mg/kg in liver. The median guaifenesin central blood to peripheral blood ratio was 1.1 (N=8). Similarly, liver to peripheral blood ratios showed a median value of 0.9L/kg (N=5). Given that a liver to peripheral blood ratio less than 5L/kg is consistent with little to no propensity for postmortem redistribution, these data suggest that guaifenesin is not prone to substantial postmortem redistribution. Published by Elsevier Ireland Ltd.

  12. Genetic and toxinological characterization of North Atlantic strains of the dinoflagellate Ostreopsis and allelopathic interactions with toxic and non-toxic species from the genera Prorocentrum, Coolia and Gambierdiscus.

    Science.gov (United States)

    García-Portela, María; Riobó, Pilar; Franco, José Mariano; Bañuelos, Rosa Mª; Rodríguez, Francisco

    2016-12-01

    The genus Ostreopsis includes several toxic species that can develop blooms in benthic ecosystems, with potential harmful consequences for human health and marine invertebrates. Despite of this, little is known about the allelopathic interactions between these organisms and other co-occurring microalgae that exploit similar spatial and nutrient resources in benthic ecosystems. The aim of this study was to follow these interactions in cultures of two Ostreopsis ribotypes with different toxin profiles (O. cf. ovata contained ovatoxins-a, b, c and e, while only ovatoxin-d was found in O .sp. "Lanzarote-type"), mixed with species of three benthic dinoflagellate genera (Coolia, Prorocentrum and Gambierdiscus), isolated from the same area (North East Atlantic, Canary Islands). In a first experiment, the potential allelopathic effects on growth rates were followed, in mixed cultures of Coolia monotis (a non toxic species) exposed to the clarified medium and to cells of O. sp."Lanzarote-type" and O. cf. ovata. Growth delayed in C. monotis was observed specially in clarified medium, while the O. sp. "Lanzarote-type" strain attained much lower densities in mixed cultures. In a second experiment, we examined the potential effects of clarified media from O. sp."Lanzarote-type" and O. cf. ovata on the adherence capacity in two toxic species (Prorocentrum hoffmannianum and Gambierdiscus excentricus). Contrasting effects were found: a significant increase of adherence capacity in P. hoffmannianum vs attachment decline in G. excentricus, that experienced also severe deleterious effects (cell lysis). Our results suggest the existence of weak to moderate allelopathic interactions between the studied organisms, although the outcome is dependent on the species involved.

  13. Epigallocatechin-3-gallate and related phenol compounds redirect the amyloidogenic aggregation pathway of ataxin-3 towards non-toxic aggregates and prevent toxicity in neural cells and Caenorhabditis elegans animal model.

    Science.gov (United States)

    Visentin, Cristina; Pellistri, Francesca; Natalello, Antonino; Vertemara, Jacopo; Bonanomi, Marcella; Gatta, Elena; Penco, Amanda; Relini, Annalisa; De Gioia, Luca; Airoldi, Cristina; Regonesi, Maria E; Tortora, Paolo

    2017-09-01

    The protein ataxin-3 (ATX3) triggers an amyloid-related neurodegenerative disease when its polyglutamine stretch is expanded beyond a critical threshold. We formerly demonstrated that the polyphenol epigallocatechin-3-gallate (EGCG) could redirect amyloid aggregation of a full-length, expanded ATX3 (ATX3-Q55) towards non-toxic, soluble, SDS-resistant aggregates. Here, we have characterized other related phenol compounds, although smaller in size, i.e. (-)-epigallocatechin gallate (EGC), and gallic acid (GA). We analysed the aggregation pattern of ATX3-Q55 and of the N-terminal globular Josephin domain (JD) by assessing the time course of the soluble protein, as well its structural features by FTIR and AFM, in the presence and the absence of the mentioned compounds. All of them redirected the aggregation pattern towards soluble, SDS-resistant aggregates. They also prevented the appearance of ordered side-chain hydrogen bonding in ATX3-Q55, which is the hallmark of polyQ-related amyloids. Molecular docking analyses on the JD highlighted three interacting regions, including the central, aggregation-prone one. All three compounds bound to each of them, although with different patterns. This might account for their capability to prevent amyloidogenesis. Saturation transfer difference NMR experiments also confirmed EGCG and EGC binding to monomeric JD. ATX3-Q55 pre-incubation with any of the three compounds prevented its calcium-influx-mediated cytotoxicity towards neural cells. Finally, all the phenols significantly reduced toxicity in a transgenic Caenorhabditis elegans strain expressing an expanded ATX3. Overall, our results show that the three polyphenols act in a substantially similar manner. GA, however, might be more suitable for antiamyloid treatments due to its simpler structure and higher chemical stability. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  14. Stimulation of Wild-Type, F508del- and G551D-CFTR Chloride Channels by Non-Toxic Modified pyrrolo[2,3-b]pyrazine Derivatives.

    Science.gov (United States)

    Dannhoffer, Luc; Billet, Arnaud; Jollivet, Mathilde; Melin-Heschel, Patricia; Faveau, Christelle; Becq, Frédéric

    2011-01-01

    Cystic fibrosis (CF) is a major inherited disorder involving abnormalities of fluid and electrolyte transport in a number of different organs due to abnormal function of cystic fibrosis transmembrane conductance regulator (CFTR) protein. We recently identified a family of CFTR activators, which contains the hit: RP107 [7-n-butyl-6-(4-hydroxyphenyl)[5H]-pyrrolo[2,3-b]pyrazine]. Here, we further evaluated the effect of the chemical modifications of the RP107-OH radical on CFTR activation. The replacement of the OH radical by a fluorine atom at position 2 (RP193) or 4 (RP185) significantly decreased the toxicity of the compounds without altering the ability to activate CFTR, especially for RP193. The non-toxic compound RP193 has no effect on cAMP production but stimulates the channel activity of wild-type CFTR in stably transfected CHO cells, in human bronchial epithelial NuLi-1 cells, and in primary culture of human bronchial epithelial cells (HBEC). Whole-cell and single patch-clamp recordings showed that RP193 induced a linear, time- and voltage-independent current, which was fully inhibited by two different and selective CFTR inhibitors (CFTRinh-172 and GP(inh)5a). Moreover, RP193 stimulates CFTR in temperature-rescued CuFi-1 (F508del/F508del) HBEC and in CHO cells stably expressing G551D-CFTR. This study shows that it is feasible to reduce cytotoxicity of chemical compounds without affecting their potency to activate CFTR and to rescue the class 2 F508del-CFTR and class 3 G551D-CFTR CF mutant activities.

  15. The refining of soybean oil to optimum quality

    Directory of Open Access Journals (Sweden)

    Rusell, J.

    1996-08-01

    Full Text Available One of the objectives of the American Soybean Association is to improve the quality of soybean and related products in Turkey. In order to achieve this, a number of extraction plants and refineries were visited to enable first hand information to be obtained on the type of equipment used in all unit processes, the methodology employed, quality standards and levels of efficiency. The culmination of the visit was a seminar organised jointly by the American Soybean Association and the Turkish Vegetable Oil Association in Istanbul on 22nd September 1989, at which a paper with the above title was presented. A reproduction of this paper is attached which briefly describes the critical areas of soybean oil processing and includes recommendations for quality improvements. It concludes with the comment that provided proper care is taken and optimum refining processes employed, including hydrogenation where appropriate, an impressive range of oils, margarines and shortenings of high quality can ben produced. The author would like to record his grateful thanks to Dr. R. Leysen of the American Soybean Association for all his help and guidance, to Mr. Kenon Marasoglu, Chairman of the Turkish Vegetable Oil Association and to the management and staff of all the factories visited. Acknowledgement is also made to Dr. D. R. Arickson and Mr. L. H. Wiedermann of the American Soybean Association for the use of some technical information from a paper entitled «Soybean Oil-Modern Processing and Utilisation» which is to be published shortly.

    Uno de los objetivos de la Asociación Americana de Soja en Turquía es mejorar la calidad de la soja y de los productos relacionados. En orden a conseguir esto, diversas plantas de extracción y refinerías fueron visitadas para permitir obtener de primera mano información sobre el tipo de equipo usado en todas las unidades de proceso, la metodología empleada, los estándar de calidad y los niveles de eficacia. La

  16. Rotation Angle for the Optimum Tracking of One-Axis Trackers

    Energy Technology Data Exchange (ETDEWEB)

    Marion, W. F.; Dobos, A. P.

    2013-07-01

    An equation for the rotation angle for optimum tracking of one-axis trackers is derived along with equations giving the relationships between the rotation angle and the surface tilt and azimuth angles. These equations are useful for improved modeling of the solar radiation available to a collector with tracking constraints and for determining the appropriate motor revolutions for optimum tracking.

  17. Rotation Angle for the Optimum Tracking of One-Axis Trackers

    Energy Technology Data Exchange (ETDEWEB)

    Marion, W. F.; Dobos, A. P.

    2013-07-01

    An equation for the rotation angle for optimum tracking of one-axis trackers is derived along with equations giving the relationships between the rotation angle and the surface tilt and azimuth angles. These equations are useful for improved modeling of the solar radiation available to a collector with tracking constraints and for determining the appropriate motor revolutions for optimum tracking.

  18. Optimum poultry litter rates for maximum profit vs. yield in cotton production

    Science.gov (United States)

    Cotton lint yield responds well to increasing rates of poultry litter fertilization, but little is known of how optimum rates for yield compare with optimum rates for profit. The objectives of this study were to analyze cotton lint yield response to poultry litter application rates, determine and co...

  19. Detailed discussion of the optimum baud rate of nonlinearity in WDM transmission

    Science.gov (United States)

    Wang, Wanli; Qiao, Yaojun; Yang, Lin

    2017-01-01

    Different numbers of sub-channels correspond to different baud rates per sub-channel when the total baud rate is fixed. The optimum baud rate of nonlinearity in WDM systems is investigated in this paper. We find that the phase matching effect produces an optimum baud rate of nonlinearity, which is related to the chromatic dispersion accumulation of a single span. Then other factors that influence the optimum baud rate are analyzed. By mathematical derivation and simulation verification, larger number of spans and larger spectrum gap between sub-channels both make the optimum value decrease. We also find that different modulation formats barely change the optimum baud rate if other system settings are the same and all sub-channels have the same modulation format.

  20. Optimum synthesis conditions of nanometric Fe50Ni50 alloy formed by chemical reduction in aqueous solution

    Indian Academy of Sciences (India)

    Marwa A Mohamed; Azza H El-Maghraby; Mona M Abd El-Latif; Hassan A Farag

    2013-10-01

    In the present article, various nanometric Fe50Ni50 alloys were synthesized by chemical reduction of the corresponding metal ions, with hydrazine in an aqueous solution. Process variables of reaction temperature, pH of the hydrazine solution and concentration of metal ions were varied in order to determine the optimum synthesis conditions regarding quality, productivity and cost. It is found that pH of hydrazine solution, at low concentration of metal ions, is the most crucial variable affecting the reaction rate, average crystallite and particle sizes of the synthesized nanometric Fe50Ni50 alloy, followed by the total concentration of metal ions. Thus, increase of pH of hydrazine solution acts as an efficient stabilizer in reducing the particle size. On the contrary, at high concentration of metal ions, the structural characteristics of the nanometric Fe50Ni50 alloy are almost insensitive to reaction temperature and pH of hydrazine solution, but the reduction rate is remarkably sensitive to reaction temperature. Based on these results, it is decided that a reaction temperature of 80 °C, pH of the hydrazine solution of 12.5 and concentration of metal ions of 0.6 M represent the optimum synthesis conditions. The role of pH of hydrazine solution in reducing the alloy’s average particle size as well as efficient stabilizer confirms tremendous effect of synthesis conditions on the alloy structure and therefore, the importance of this study for industrial production of nanometric Fe50Ni50 alloy.

  1. Low concentrator PV optics optimization

    Science.gov (United States)

    Sharp, Leonard; Chang, Ben

    2008-08-01

    Purpose: Cost reduction is a major focus of the solar industry. Thin film technologies and concentration systems are viable ways to reducing cost, with unique strengths and weakness for both. Most of the concentrating PV work focuses on high concentration systems for reducing energy cost. Meanwhile, many believe that low concentrators provide significant cost reduction potential while addressing the mainstream PV market with a product that acts as a flat panel replacement. This paper analyzes the relative benefit of asymmetric vs. symmetric optics for low-concentrators in light of specific PV applications. Approach: Symmetric and asymmetric concentrating PV module performance is evaluated using computer simulation to determine potential value across various geographic locations and applications. The selected optic design is modeled against standard cSi flat panels and thin film to determine application fit, system level energy density and economic value. Results: While symmetric designs may seem ideal, asymmetric designs have an advantage in energy density. Both designs are assessed for aperture, optimum concentration ratio, and ideal system array configuration. Analysis of performance across climate specific effects (diffuse, direct and circumsolar) and location specific effects (sunpath) are also presented. The energy density and energy production of low concentrators provide a compelling value proposition. More significantly, the choice of optics for a low concentrating design can affect real world performance. With the goal of maximizing energy density and return on investment, this paper presents the advantages of asymmetric optic concentration and illustrates the value of this design within specific PV applications.

  2. Biological identification and determination of optimum growth conditions for four species ofNavicula

    Institute of Scientific and Technical Information of China (English)

    ZHAO Xiaobo; PANG Shaojun; LIU Feng; SHAN Tifeng; LI Jing

    2014-01-01

    Four species in the genus Navicula were isolated using the serial dilution method. Based on scanning elec-tron microscopy (SEM) and sequence comparisons of two segments of genes (small ribosomal subunit and large subunit of Rubisco), the species were identified asNavicula perminuta,N. pseudacceptata,N. vara, andN. rhynchocephala. Based on phylogenetic analysis and culture trials,there was a close relationship betweenN. perminutaandN. vara. Growth of these species was evaluated using measurements of optical density at 680 nm (OD680) under various environmental factors. Results showed that the optimum culture conditions were 25°C, 50-100 μmol photons m-2 s-1, pH 8.0, and salinities from 25 to 30. However, the favor-able salinity forN. perminuta was surprisingly high at 35. Nutrient requirement analysis demonstrated that growth ofNavicula depended on the availability of SiO32-. Their relative growth rates (RGR) peaked at the highest tested level (0.25 mmol/L). The optimal concentrations of NO3-and PO43- were 3.6 mmol/L and 0.18 mmol/L, respectively. Culture of theseNavicula species for abalone or sea cucumber aquaculture should take these factors into consideration.

  3. Optimum culture medium composition for lipopeptide production by Bacillus subtilis using response surface model-based ant colony optimization

    Indian Academy of Sciences (India)

    J Satya Eswari; M Anand; C Venkateswarlu

    2016-01-01

    Central composite rotatable design (CCRD) of experiments was used to obtain data for Lipopeptide and Biomass concentrations from fermentation medium containing the following five components: glucose,monosodium glutamate, yeast extract,MgSO4·7H2O, and K2HPO4. Data was used to develop a second order regression response surface model (RSM) which was coupled with ant colony optimization (ACO) to optimize the media compositions so as to enhance the productivity of lipopeptide. The optimized media by ACO was found to yield 1.501 g/L of lipopeptide concentration which was much higher compared to 1.387 g/L predicted by Nelder–Mead optimization (NMO). The optimum from ACO was validated experimentally. RSM-based ACO is thus shown to be an effective tool for medium optimization of biosurfactant production.

  4. Optimum sensor placement in microchannel reactors: design tool applications

    Science.gov (United States)

    Sen, Mehmet; Fiering, Jason; Kowalski, Gregory J.; Larson, Dale

    2011-02-01

    A computational analysis of a microchannel reacting flow that includes diffusion and heat transfer processes to determine design rules for sensor placement is described. The objective is to optimize the positioning of nanohole array sensors which measure concentration and temperature and to analyze the characteristics of the local quantities sensed by nanohole arrays. Because the position and minimum spacing of the sensors are limited by material and fabrication constraints, the computational analysis is used to verify the effectiveness and limitations of this approach. Thermal boundary analysis is performed to analyze the relation between the sensed layer (micro-sensing region) over the nanohole array sensors and the boundary layer development. The relationship between the sensor position and the nodes of the numerical solution that limit this design process are discussed.

  5. Optimum Tilt Angle for Photovoltaic Solar Panels in Zomba District, Malawi

    Directory of Open Access Journals (Sweden)

    B. Kamanga

    2014-01-01

    Full Text Available A study to determine the optimum tilt angle for installing photovoltaic solar panels in Zomba district, Malawi, has been conducted. The study determined the optimum monthly tilt angles of PV solar panels and the seasonal adjustments needed for the panels in order to collect maximum solar radiation throughout the year. In this study, global solar radiation (GSR on four tilted surfaces was measured. The north-facing surfaces were titled at angles of 0°, 15°, 20°, and 25°. The GSR data was used to determine the daily and monthly optimum tilt angles for the PV panels. The optimum tilt angles were found to be 0° or 25° depending on the time of the year. From October to February, the optimum tilt angle has been determined to be 0° and, from March to September, the optimum tilt angle is observed to be 25°. There are only two seasonal adjustments that are needed for PV solar panels in Zomba district and these should be carried out at the end of February and at the end of September. For fixed solar panels with no seasonal adjustments, the optimum tilt angle for the PV solar panels that are northfacing has been determined to be 25°.

  6. Synthesis of Nano-sized Boehmites for Optimum Phosphate Sorption

    DEFF Research Database (Denmark)

    Watanabe, Yujiro; Kasama, Takeshi; Fukushi, Keisuke;

    2011-01-01

    Nano-sized boehmites with different crystallinity were synthesized at the temperature range of 25 to 200°C in order to produce phosphate absorbents with high capacity. The physicochemical property of boehmites was depended on the synthesis temperature: the particle size was increased and the surf......Nano-sized boehmites with different crystallinity were synthesized at the temperature range of 25 to 200°C in order to produce phosphate absorbents with high capacity. The physicochemical property of boehmites was depended on the synthesis temperature: the particle size was increased...... and the surface area showed the maximum for the boehmite at 50°C. The phosphate sorptions into boehmites were analyzed at room temperature in the phosphoric acid solutions as a model of wastewater at the concentration of 0.1 to 3.0 mmol l-1 and the pH of 3 to 7. The boehmite synthesized at 50°C exhibited...... the highest amount of phosphate sorption (1.73 mmol g-1 at pH 3.3) compared with Al-bearing materials. The reaction mechanism during phosphate sorption was described by the anion exchange reaction between phosphate ions in sodium phosphate solution and hydroxide ions on boehmite surfaces. Therefore...

  7. Optimum polygenic profile to resist exertional rhabdomyolysis during a marathon

    Science.gov (United States)

    Valero, Marjorie; Salinero, Juan José; Lara, Beatriz; Gallo-Salazar, César; Areces, Francisco

    2017-01-01

    Purpose Exertional rhabdomyolysis can occur in individuals performing various types of exercise but it is unclear why some individuals develop this condition while others do not. Previous investigations have determined the role of several single nucleotide polymorphisms (SNPs) to explain inter-individual variability of serum creatine kinase (CK) concentrations after exertional muscle damage. However, there has been no research about the interrelationship among these SNPs. The purpose of this investigation was to analyze seven SNPs that are candidates for explaining individual variations of CK response after a marathon competition (ACE = 287bp Ins/Del, ACTN3 = p.R577X, CKMM = NcoI, IGF2 = C13790G, IL6 = 174G>C, MLCK = C37885A, TNFα = 308G>A). Methods Using Williams and Folland’s model, we determined the total genotype score from the accumulated combination of these seven SNPs for marathoners with a low CK response (n = 36; serum CK exercise training, might also play a role in the values of CK after damaging exercise. PMID:28257486

  8. Calibration of handheld X-ray fluorescence (XRF) equipment for optimum determination of elemental concentrations in sediment samples.

    Science.gov (United States)

    Mejía-Piña, K Gabriela; Huerta-Diaz, Miguel Angel; González-Yajimovich, O

    2016-12-01

    Handheld X-ray fluorescence spectrometers (XRFs) represent a more practical, efficient and economic tool to determine the elemental composition of solid inorganic and organic samples than conventional analytical techniques. The objective of this work was to demonstrate that handheld XRFs could be a precise, accurate and reliable tool to analyze up to 27 different elements. This objective was accomplished through the optimization of an empirical calibration curve that, in addition to include certified reference materials (CRM), it also introduced new approaches, such as the use of solid CRM mixtures and combinations of organic and inorganic matrices. These approaches significantly increased the number of calibration points and eliminated hiatuses in the calibration curve. Several factors were evaluated before construction of the calibration curve: incidence time of the X-ray beam, type of film through which the X-ray beams reach the samples, container type, minimum sample volume and sample moisture content. Results show that single elements can be analyzed with variable exposure times or, alternatively, multielemental analyses can be carried out with a constant exposure time (180s). Costs can be reduced by using Ziploc(®) bags as sample containers, but the number of measurable elements drops from 27 to 21, while the possibility of contamination increases.

  9. Study on the optimum design of bus window pillar join40t; Bus window pillar ketsugo buzai no saiteki sekkei ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Tomioka, N. [Nihon University, Tokyo (Japan); Lim, S.; Kim, M.; Lee, H.; Kang, S.; Bae, D.

    1997-10-01

    Automobile body structure is generally assembled using various spot welded box sectional members. Especially, in the case of the bus, the shape of window pillar joint is assembled m T-type. This T-type member has some problem such as high stress concentration, low fatigue strength and structural rigidity. Therefore, in this report, performed a study on the optimum design of the bus window pillar joint for such problem by FEM analysis and experiments. 1 ref., 10 figs., 2 tabs.

  10. Concentrating Radioactivity

    Science.gov (United States)

    Herrmann, Richard A.

    1974-01-01

    By concentrating radioactivity contained on luminous dials, a teacher can make a high reading source for classroom experiments on radiation. The preparation of the source and its uses are described. (DT)

  11. Optimum Wing Shape Determination of Highly Flexible Morphing Aircraft for Improved Flight Performance

    Science.gov (United States)

    Su, Weihua; Swei, Sean Shan-Min; Zhu, Guoming G.

    2016-01-01

    In this paper, optimum wing bending and torsion deformations are explored for a mission adaptive, highly flexible morphing aircraft. The complete highly flexible aircraft is modeled using a strain-based geometrically nonlinear beam formulation, coupled with unsteady aerodynamics and six-degrees-of-freedom rigid-body motions. Since there are no conventional discrete control surfaces for trimming the flexible aircraft, the design space for searching the optimum wing geometries is enlarged. To achieve high performance flight, the wing geometry is best tailored according to the specific flight mission needs. In this study, the steady level flight and the coordinated turn flight are considered, and the optimum wing deformations with the minimum drag at these flight conditions are searched by utilizing a modal-based optimization procedure, subject to the trim and other constraints. The numerical study verifies the feasibility of the modal-based optimization approach, and shows the resulting optimum wing configuration and its sensitivity under different flight profiles.

  12. Application of computer-aided engineering optimum design method in aluminum profile extrusion mould

    Institute of Scientific and Technical Information of China (English)

    帅词俊; 肖刚; 倪正顺; 钟掘

    2003-01-01

    The finite element analysis and the optimum design of aluminum profile extrusion mould were investigated using the ANSYS software and its parameterized modeling method. The optimum dimensions of the mould were obtained. It is found that the stress distribution is very uneven, and the stress convergence is rather severe in the bridge of the aluminum profile extrusion mould. The optimum height of the mould is 70. 527 mm, and the optimum radius of dividing holes are 70. 182 mm and 80. 663 mm. Increasing the height of the mould in the range of 61. 282 mm to 70. 422 mm can prolong its longevity, but when the height is over 70. 422 mm, its longevity reduces.

  13. OPTIMUM ALLOCATION OF WATER TO THE CULTIVATION FARMS USING GENETIC ALGORITHM

    Directory of Open Access Journals (Sweden)

    B. Saeidian

    2015-12-01

    By optimum allocation of the water to the farms with different areas and crop types, and considering the deficit irrigation method, the general income of the entire area can be improved substantially.

  14. Asymptotically Optimum Universal One-Bit Watermarking for Gaussian Covertexts and Gaussian Attacks

    CERN Document Server

    Comesaña, P; Barni, M

    2008-01-01

    The problem of optimum watermark embedding and detection was addressed in a recent paper by Merhav and Sabbag, where the optimality criterion was the maximum false-negative error exponent subject to a guaranteed false-positive error exponent. In particular, Merhav and Sabbag derived universal asymptotically optimum embedding and detection rules under the assumption that the detector relies solely on second order joint empirical statistics of the received signal and the watermark. In the case of a Gaussian host signal and a Gaussian attack, however, closed-form expressions for the optimum embedding strategy and the false-negative error exponent were not obtained in that work. In this paper, we derive such expressions, again, under the universality assumption that neither the host variance nor the attack power are known to either the embedder or the detector. The optimum embedding rule turns out to be very simple and with an intuitively-appealing geometrical interpretation. The improvement with respect to exist...

  15. OPTIMUM PLANNING OF EXPERIMENTS AT MODELING FUEL CONSUMPTION IN INTERNAL COMBUSTION ENGINES

    Directory of Open Access Journals (Sweden)

    N. Koshevoy

    2009-01-01

    Full Text Available The efficiency of optimum experiments planning by cost expenses at studying the processes of fuel consumption internal combustion engines is shown. The mathematical models of these processes in different state of engine working are synthesized.

  16. The Optimum Design of Hydrodynamic Lubrication Bearing for Minimization of the Total Life Cost

    Science.gov (United States)

    Iwatsubo, Takuzo; Yamabayashi, Jun

    This paper proposes an optimum design method of journal bearing for minimizing the total life cost which includes not only the initial cost but also the running cost. Journal bearing is one of the typical friction part and physically severe part in machine elements. Therefore, maintenance is required to prevent failure and to keep performance. For this object, the running cost by the maintenance is user's burden. Thus, the optimum design method of the bearing for minimization of the total life cost is required. In this research, the evaluation functions of the total life cost which contains the initial cost and the running cost of the bearing are discussed and the optimum design is proposed under the physical constrain, that is Thermo Hydrodynamic Lubrication theory (THL theory), and inequality constraints. Then design valuables of the optimum journal bearing are obtained.

  17. Optimum distribution of heat exchanger inventory for power density optimization of an endoreversible closed Brayton cycle

    Energy Technology Data Exchange (ETDEWEB)

    Lingen Chen; Junlin Zheng; Fengrui Sun [Naval Univ. of Engineering, Faculty 306, Wuhan (China); Chih Wu [U.S. Naval Academy, Mechanical Engineering Dept., Annapolis, MD (United States)

    2001-02-07

    In this paper, the power density (defined as the ratio of the power output to the maximum specific volume in the cycle) is taken as the objective for performance optimisations of an endoreversible closed Brayton cycle coupled to constant-temperature heat reservoirs in the viewpoint of finite-time thermodynamics (FTT) or entropy generation minimisation (EGM). The optimum heat conductance distribution corresponding to the optimum power density of the hot- and cold-side heat exchangers for the fixed heat exchanger inventory is analysed using numerical examples. The influence of some design parameters on the optimum heat conductance distribution and the maximum power density and the optimum pressure ratio corresponding to the maximum power density are provided. The power plant design with optimisation leads to higher efficiency and smaller size. (Author)

  18. Dexmedetomidine provides optimum conditions during awake fiberoptic intubation in simulated cervical spine injury patients

    Directory of Open Access Journals (Sweden)

    Pooja Chopra

    2016-01-01

    Conclusions: Dexmedetomidine provides optimum sedation without compromising airway or hemodynamic instability with better patient tolerance and satisfaction for AFOI. It also preserves patient arousability for the postintubation neurological assessment.

  19. Face Recognition of Illumination Tolerance in 2D Subspace Based on the Optimum Correlation Filter

    National Research Council Canada - National Science Library

    Yi Xu

    2014-01-01

    ... subspace based on the optimal correlation filter. Firstly, through the use of a particular class 2D-PCA the face image is reconstructed and by using the optimum projecting image correlation filter (OPICF...

  20. NOAA Optimum Interpolation 1/4 Degree Daily Sea Surface Temperature (OISST) Analysis, Version 2

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This high-resolution sea surface temperature (SST) analysis product was developed using an optimum interpolation (OI) technique. The SST analysis has a spatial grid...

  1. Identification of optimum outfall location for desalination plant in the coastal waters off Tuticorin, India

    Digital Repository Service at National Institute of Oceanography (India)

    DineshKumar, P.K.; NaveenKumar, K.R.; Muraleedharan, K.R.

    values. It is suggested that the offshore waters at a distance of 2 Km away from the coastline could be considered as optimum where the environmental impact on the ecosystem due to the disposal operations is considered to be minimum...

  2. Optimum Design of 1st Gear Ratio for 4WD Vehicles Based on Vehicle Dynamic Behaviour

    OpenAIRE

    M. H. Shojaeefard; Talebitooti,R.; Sadegh Yarmohammadi Satri

    2013-01-01

    This paper presents an approach that allows optimizing gear ratio and vehicle dimension to achieve optimum gear transmission. Therefore, augmented Lagrangian multiplier method, defined as classical method, is utilized to find the optimum gear ratios and the corresponding number of gear teeth applied to all epicyclical gears. The new method is able to calculate and also to optimize the gear ratio based on dynamics of 4WD vehicles. Therefore, 4WD vehicles dynamic equations are employed assuming...

  3. Optimum deconvolution algorithm for system with multiplicative white noise and additive correlative noise

    Institute of Scientific and Technical Information of China (English)

    王会立; 陈希信

    2004-01-01

    The optimum state filter and fixed-interval smoother and the optimum deconvolution algorithm for system with multiplicative noise are derived upon the condition that the dynamic noise correlates itself in one-step and correlates with the measurement noise at the present step as well as one past step, and the multiplicative noise is white and statistically independent of the dynamic noise and the measurement noise. A simulation example demonstrates the effectiveness of the above-mentioned deconvolution algorithm.

  4. Developing an Optimum Protocol for Thermoluminescence Dosimetry with GR-200 Chips using Taguchi Method.

    Science.gov (United States)

    Sadeghi, Maryam; Faghihi, Reza; Sina, Sedigheh

    2016-11-24

    Thermoluminescence dosimetry (TLD) is a powerful technique with wide applications in personal, environmental and clinical dosimetry. The optimum annealing, storage and reading protocols are very effective in accuracy of TLD response. The purpose of this study is to obtain an optimum protocol for GR-200; LiF: Mg, Cu, P, by optimizing the effective parameters, to increase the reliability of the TLD response using Taguchi method. Taguchi method has been used in this study for optimization of annealing, storage and reading protocols of the TLDs. A number of 108 GR-200 chips were divided into 27 groups, each containing four chips. The TLDs were exposed to three different doses, and stored, annealed and read out by different procedures as suggested by Taguchi Method. By comparing the signal-to-noise ratios the optimum dosimetry procedure was obtained. According to the results, the optimum values for annealing temperature (°C), Annealing Time (s), Annealing to Exposure time (d), Exposure to Readout time (d), Pre-heat Temperature (°C), Pre-heat Time (s), Heating Rate (°C/s), Maximum Temperature of Readout (°C), readout time (s) and Storage Temperature (°C) are 240, 90, 1, 2, 50, 0, 15, 240, 13 and -20, respectively. Using the optimum protocol, an efficient glow curve with low residual signals can be achieved. Using optimum protocol obtained by Taguchi method, the dosimetry can be effectively performed with great accuracy.

  5. Determine Neuronal Tuning Curves by Exploring Optimum Firing Rate Distribution for Information Efficiency

    Science.gov (United States)

    Han, Fang; Wang, Zhijie; Fan, Hong

    2017-01-01

    This paper proposed a new method to determine the neuronal tuning curves for maximum information efficiency by computing the optimum firing rate distribution. Firstly, we proposed a general definition for the information efficiency, which is relevant to mutual information and neuronal energy consumption. The energy consumption is composed of two parts: neuronal basic energy consumption and neuronal spike emission energy consumption. A parameter to model the relative importance of energy consumption is introduced in the definition of the information efficiency. Then, we designed a combination of exponential functions to describe the optimum firing rate distribution based on the analysis of the dependency of the mutual information and the energy consumption on the shape of the functions of the firing rate distributions. Furthermore, we developed a rapid algorithm to search the parameter values of the optimum firing rate distribution function. Finally, we found with the rapid algorithm that a combination of two different exponential functions with two free parameters can describe the optimum firing rate distribution accurately. We also found that if the energy consumption is relatively unimportant (important) compared to the mutual information or the neuronal basic energy consumption is relatively large (small), the curve of the optimum firing rate distribution will be relatively flat (steep), and the corresponding optimum tuning curve exhibits a form of sigmoid if the stimuli distribution is normal. PMID:28270760

  6. Morphology-controllable growth of GdVO4:Eu3+ nano/microstructures for an optimum red luminescence

    Science.gov (United States)

    Yang, Liusai; Li, Guangshe; Zhao, Minglei; Zheng, Jing; Guan, Xiangfeng; Li, Liping

    2012-06-01

    Chemically tailoring microstructures for an optimum red luminescence is a subject at the forefront of many disciplines, which still remains a challenge due to a poor knowledge about the roles of defects in structures. In this work, GdVO4 :Eu3+ nano/microstructures of different morphologies, including tomato-like, cookie-circle-like, and ellipsoidal-like nanoparticles, and microspheroids were synthesized via a simple hydrothermal route using trisodium citrate as a capping agent. During the growth processes, the types of vanadyl ions were adjusted by varying pH value to control the morphologies and nano/microstructures with the help of trisodium citrate. The possible mechanisms for the growth processes into diverse morphologies are presented. Further, a systematic study on defect characteristics pertinent to these diverse morphologies has been explored to achieve an optimum red luminescence. The ability is clearly shown to generate different nano/microstructures of diverse morphologies and varied defect concentrations, which provides a great opportunity for morphological control in tailoring the red luminescence property for many technological applications.

  7. Penentuan Kondisi Optimum Ukuran Partikel dan Bilangan Reynold Pada Sintesis Bioplastik Berbasis Sorgum

    Directory of Open Access Journals (Sweden)

    Yuli Darni

    2011-12-01

    Full Text Available The article reported the laboratory experiment to obtain the optimal condition of particle size and Reynold Number of bioplastic film based on the plastic package standard of High Density Polyethylene (HDPE.  Particle sizes of starch were varied at 63, 90, 106, 600, and 1000 micron, and the mixing rate were changes at 190, 252, 313, 375, and 437 rpm. The concentration of chitosan and gliserol added to solution were set as constant variable as 20 and 10 wt %, respectively. The temperature of gelatinitation was also fixed at 95OC. The fabricated of bioplastic film were characterized for mechanical property such as tensile strength, elongation at break and Modulus Young by using a  Universal Testing Machine. The  morphology of film sheets were observed by using a scanning electron microscopy (SEM. Moreover, the obtained film was also investigated for water uptake parameter. The result showed that the mechanical properties were improve by increasing mixing rate at smallest particle sizes of starch. The water uptakes shows decrease at hight mixing rate. SEM images showed that the morphology of bioplastic was almost simmilar to the morphology of  HDPE.  The optimum condition was found that the best film was obtained at particle size of starch 63 micron, Reynold Number of  959, with mixing rate of  375 rpm. The mechanical value at best condition was 19.27%, 757.046 Mpa, and 142.875 for elongation, Modulus Young,  and tensile strength, respectively. Keywords: bioplastic, reynold Number, starch, sorgum

  8. Optimum extraction process of polyphenols from the bark of Phyllanthus emblica L. based on the response surface methodology.

    Science.gov (United States)

    Yang, Li; Jiang, Jian-Guo; Li, Wei-Feng; Chen, Jian; Wang, Ding-Yong; Zhu, Liang

    2009-05-01

    Phyllanthus emblica L. is an economic plant used in Chinese medicine for the treatment of various diseases. The bark of P. emblica is rich in polyphenols and its extractions have shown strong antioxidative and radical scavenging activity. Response surface methodology (RSM) was used to assess the optimal extraction of polyphenols from P. emblica bark. Various extraction parameters including ethanol concentration, extraction time, temperature, solid-liquid ratio, and extraction times were chosen to identify their effects on polyphenols extraction. Among these parameters, extraction times and solvent concentration were found to have significant effect on polyphenols extraction. RSM was applied to obtain the optimal combination of solvent concentration, extraction time, temperature, and extraction time for maximum rate of extraction. The most suitable condition for the extraction of polyphenols was at ethanol concentration 75%, extraction time 25 min, extraction temperature 45 degrees C, and extraction times 3. At these optimal extraction parameters, the maximum extraction of polyphenols obtained experimentally was found to be very close to its predicted value. The extraction rate of polyphenols was 19.78% at the optimum conditions. The mathematical model developed was found to fit with the experimental data of polyphenols extraction.

  9. Total reflection x-ray fluorescence: Determination of an optimum geometry

    Energy Technology Data Exchange (ETDEWEB)

    Koo, Y.M. [Pohang Univ. of Science and Technology (Korea, Republic of); Chang, C.H.; Padmore, H.A. [Ernest Orlando Lawrence Berkeley National Lab., CA (United States)

    1997-04-01

    Total reflection X-Ray Fluorescence (TXRF) is a widely used technique in which the normal trace element detection capability of hard x-ray fluorescence (XRF) is enhanced by use of an x-ray reflective substrate. TXRF is more sensitive than normal photon induced XRF due to the reduction of the substrate scattering and fluorescence signals. This reduction comes about because in total external reflection, the photon field only penetrates about 20 {angstrom} into the surface, instead of typically 50 {mu}m for a silicon substrate at normal incidence for 10 KeV photons. The technique is used in many fields of trace element analysis, and is widely used in the determination of metal impurity concentrations on and in the surface of silicon wafers. The Semiconductor Industry Association roadmap (SIA) indicates a need for wafer contamination detection at the 10{sup 7}atoms/cm{sup 2} level in the next few years. Current commercial systems using rotating anode x-ray sources presently routinely operate with a sensitivity level of around 10{sup 10} atoms/cm{sup 2} and this has led to interest in the use of synchrotron radiation to extend the sensitivity by three orders of magnitude. The pioneering work of Pianetta and co-workers at SSRL has clearly shown that this should be possible, using a fully optimized source and detector. The purpose of this work is to determine whether ALS would be a suitable source for this type of highly sensitive wafer TXRF. At first look it appears improbable as the SSRL work used a high flux multipole wiggler source, and it is clear that the detected fluorescence for relevant concentrations is small. In addition, SSRL operates at 3.0 GeV rather than 1.9 GeV, and is therefore more naturally suited to hard x-ray experiments. The aim of this work was therefore to establish a theoretical model for the scattering and fluorescence processes, so that one could predict the differences between alternative geometries and select an optimum configuration.

  10. Verification of the optimum tropospheric parameters setting for the kinematic PPP analysis

    Science.gov (United States)

    Hirata, Y.; Ohta, Y.

    2015-12-01

    Kinematic GNSS analysis is useful for extraction of the crustal deformation phenomena between seconds to one day such as coseismic and postseismic deformation after a large earthquake. The kinematic GNSS analysis, however, have fundamental difficulties for the separation between unknown parameters such as the site coordinate and tropospheric parameters, caused by a strong correlation between each other. Thus, we focused on the improvement of the separation precision between coordinate time series of kinematic PPP and wet zenith tropospheric delay (WZTD) based on the comprehensive search of the parameter space. We used GIPSY-OASIS II Ver. 6.3 software for kinematic PPP processing of whole GEONET sites in 10 March 2011. We applied the every 6 hours nominal WZTD value as a priori information based on the ECMWF global numerical climate model. For the coordinate time series and tropospheric parameters, we assumed white noise and random walk stochastic process, respectively. These unknown parameters are very sensitive to assumed process noise for each stochastic process. Thus, we searched for the optimum two variable parameters; wet zenith tropospheric parameter (named as TROP) and its gradient (named as GRAD). We defined the optimum parameters, which minimized the standard deviation of coordinate time series.We firstly checked the spatial distribution of optimum pair of TROP and GRAD. Even though the optimum parameters showed the certain range (TROP: 2×10-8 ~ 6×10-7 (horizontal), 5.5×10-9 ~ 2×10-8 (vertical); GRAD: 2×10-10 ~ 6×10-9 (horizontal), 2×10-10 ~ 1×10-8 (vertical) (unit: km·s-½)), we found they showed the large diversity. It suggests there are strong heterogeneity of atmospheric state. We also estimated temporal variations of optimum TROP and GRAD in specific site. We analyzed the data through 2010 at GEONET 940098 station located in the most southern part of Kyusyu, Japan. Obtained time series of optimum GRAD showed clear annual variation, and the

  11. Optimum Projection Angle for Attaining Maximum Distance in a Rugby Place Kick

    Directory of Open Access Journals (Sweden)

    Nicholas P. Linthorne

    2014-03-01

    Full Text Available This study investigated the effect of projection angle on the distance attained in a rugby place kick. A male rugby player performed 49 maximum-effort kicks using projection angles of between 20 and 50°. The kicks were recorded by a video camera at 50 Hz and a 2 D biomechanical analysis was conducted to obtain measures of the projection velocity and projection angle of the ball. The player’s optimum projection angle was calculated by substituting a mathematical expression for the relationship between projection velocity and projection angle into the equations for the aerodynamic flight of a rugby ball. We found that the player’s calculated optimum projection angle (30.6°, 95% confidence limits ± 1.9° was in close agreement with his preferred projection angle (mean value 30.8°, 95% confidence limits ± 2.1°. The player’s calculated optimum projection angle was also similar to projection angles previously reported for skilled rugby players. The optimum projection angle in a rugby place kick is considerably less than 45° because the projection velocity that a player can produce decreases substantially as projection angle is increased. Aerodynamic forces and the requirement to clear the crossbar have little effect on the optimum projection angle.

  12. Evaluation of optimum profile modification curves of profile shifted spur gears based on vibration responses

    Science.gov (United States)

    Ma, Hui; Pang, Xu; Feng, Ranjiao; Wen, Bangchun

    2016-03-01

    In this paper, a mesh stiffness model is developed for profile shifted gears with addendum modifications and tooth profile modifications (TPMs). The time-varying mesh stiffness (TVMS), load sharing factor (LSF), loaded static transmission error (LSTE) and non-loaded static transmission error (NLSTE) of a profile shifted spur gear pair with TPMs are obtained by the analytical model. The optimum profile modification curve under different amounts of TPM is determined by analyzing the LSTE first. Then, considering the effect of NLSTE, finite element (FE) model of a geared rotor system is established. The system vibration responses under different TPM curves are analyzed and the optimum modification curve is further evaluated by amplitude frequency responses. The results show that the optimum modification curve is related to the amount of TPM and modification coefficients. The comparison of the optimum profile modification curves is evaluated by LSTE and vibration responses, which shows that the optimum modification curve should be determined by evaluating the vibration response of the geared rotor system in the low mesh frequency range.

  13. Uniform and Non-Uniform Optimum Scalar Quantizers Performances: A Comparative Study

    Directory of Open Access Journals (Sweden)

    Fendy Santoso

    2008-05-01

    Full Text Available The aim of this research is to investigate source coding, the representation of information source output by finite R bits/symbol. The performance of optimum quantisers subject to an entropy constraint has been studied. The definitive work in this area is best summarised by Shannon’s source coding theorem, that is, a source with entropy H can be encoded with arbitrarily small error probability at any rate R (bits/source output as long as R>H. Conversely, If R the error probability will be driven away from zero, independent of the complexity of the encoder and the decoder employed. In this context, the main objective of engineers is however to design the optimum code. Unfortunately, the rate-distortion theorem does not provide the recipe for such a design. The theorem does, however, provide the theoretical limit so that we know how close we are to the optimum. The full understanding of the theorem also helps in setting the direction to achieve such an optimum. In this research, we have investigated the performances of two practical scalar quantisers, i.e., a Lloyd-Max quantiser and the uniformly defined one and also a well-known entropy coding scheme, i.e., Huffman coding against their theoretically attainable optimum performance due to Shannon’s limit R. It has been shown that our uniformly defined quantiser could demonstrate superior performance. The performance improvements, in fact, are more noticeable at higher bit rates.

  14. Optimum Allocation of Water to the Cultivation Farms Using Genetic Algorithm

    Science.gov (United States)

    Saeidian, B.; Saadi Mesgari, M.; Ghodousi, M.

    2015-12-01

    basis of the optimum and limited allocation of water, and not on the basis of the each crop water requirement. According to the available literature, in the condition of water scarcity, the implementation of deficit irrigation strategy results in higher economical income. The main difference of this research with others is the allocation of water to the farms. Whilst, most of similar researches concentrate on the allocation of water to different water consumption sections (such as agriculture, industry etc.), networks and crops. Using the GA for the optimization of the water allocation, proper solutions were generated that maximize the total economical income in the entire study area. In addition, although the search space was considerably wide, the results of the implementation showed an adequate convergence speed. The repeatability test of the algorithm also proved that the algorithm is reasonably stable. In general the usage of GA algorithm can be considered as an efficient and trustable method for such irrigation planning problems. By optimum allocation of the water to the farms with different areas and crop types, and considering the deficit irrigation method, the general income of the entire area can be improved substantially.

  15. Optimum Power and Rate Allocation for Coded V-BLAST: Average Optimization

    CERN Document Server

    Kostina, Victoria

    2010-01-01

    An analytical framework for performance analysis and optimization of coded V-BLAST is developed. Average power and/or rate allocations to minimize the outage probability as well as their robustness and dual problems are investigated. Compact, closed-form expressions for the optimum allocations and corresponding system performance are given. The uniform power allocation is shown to be near optimum in the low outage regime in combination with the optimum rate allocation. The average rate allocation provides the largest performance improvement (extra diversity gain), and the average power allocation offers a modest SNR gain limited by the number of transmit antennas but does not increase the diversity gain. The dual problems are shown to have the same solutions as the primal ones. All these allocation strategies are shown to be robust. The reported results also apply to coded multiuser detection and channel equalization systems relying on successive interference cancelation.

  16. DETERMINATION of OPTIMUM CONDITION of PAPAIN ENZYME FROM PAPAYA VAR JAVA (Carica papaya

    Directory of Open Access Journals (Sweden)

    Aline Puspita Kusumadjaja

    2010-06-01

    Full Text Available A study to investigate the optimum condition of papain enzyme has been carried out. The condition that are investigated are pH and temperature, based on measurement of enzyme activity which is defined as mmole tyrosin that are released in reaction between papain enzyme and casein as substrat per minute. In this research, the papain enzyme was isolated from pepaya burung varietas Java. The enzyme was partially purified by precipitation method using 30% - 50% saturated acetone. The result showed that the optimum conditions of papain enzyme are in pH 6 with activity 2,606 U/mL, and temperature at 50 oC with activity 2,469 U/mL. Keywords : Papaya var Java, papain, optimum condition, enzymatic activity

  17. Mapping of optimum operating condition for LiBr–water refrigeration cycles

    Indian Academy of Sciences (India)

    NILESH A MALI; SUNIL S BHAGWAT

    2017-02-01

    In this work, optimum operating condition maps are generated covering wide ranges of refrigeration and sink temperatures for single- and double-effect LiBr–water vapour absorption refrigeration cycle. These optimum condition maps will be useful to choose optimum operating conditions while designing LiBr–water cycle for desired applications. Methodology for generating such maps is discussed in detail, which can also beused for other absorption refrigeration cycles with various working fluids. Three configurations of LiBr–water absorption refrigeration cycles, single effect, double-effect series flow and double-effect parallel flow, are analysed with the most accurate thermodynamic property correlation available in the literature. Sensitivity of cycle performance to various operating variables such as generator, absorber and condenser temperatures is determined. Second law analysis shows that when a higher temperature heat source is available, double-effect cycles are more effective over single effect as they have higher coefficient of performance.

  18. Optimum design using VICONOPT, a buckling and strength constraint program for prismatic assemblies of anisotropic plates

    Science.gov (United States)

    Butler, R.; Williams, F. W.

    1992-01-01

    A computer program for obtaining the optimum (least mass) dimensions of the kind of prismatic assemblies of laminated, composite plates which occur in advanced aerospace construction is described. Rigorous buckling analysis (derived from exact member theory) and a tailored design procedure are used to produce designs which satisfy buckling and material strength constraints and configurational requirements. Analysis is two to three orders of magnitude quicker than FEM, keeps track of all the governing modes of failure and is efficiently adapted to give sensitivities and to maintain feasibility. Tailoring encourages convergence in fewer sizing cycles than competing programs and permits start designs which are a long way from feasible and/or optimum. Comparisons with its predecessor, PASCO, show that the program is more likely to produce an optimum, will do so more quickly in some cases, and remains accurate for a wider range of problems.

  19. Optimum Design of 1st Gear Ratio for 4WD Vehicles Based on Vehicle Dynamic Behaviour

    Directory of Open Access Journals (Sweden)

    M. H. Shojaeefard

    2013-01-01

    Full Text Available This paper presents an approach that allows optimizing gear ratio and vehicle dimension to achieve optimum gear transmission. Therefore, augmented Lagrangian multiplier method, defined as classical method, is utilized to find the optimum gear ratios and the corresponding number of gear teeth applied to all epicyclical gears. The new method is able to calculate and also to optimize the gear ratio based on dynamics of 4WD vehicles. Therefore, 4WD vehicles dynamic equations are employed assuming that the rear wheels or the front wheels are at the point of slip. In addition, a genetic algorithm is modified to preserve feasibility of the encountered solutions. The basic dimension of a sample commercial vehicle (2009 hummer H3 4dr AWD SUV and its gearbox are optimized, and then the effects of changing slip angle, wheel base, and engine torque on optimum vehicle dimension are analyzed.

  20. On optimum parameter modulation-estimation from a large deviations perspective

    CERN Document Server

    Merhav, Neri

    2012-01-01

    We consider the problem of jointly optimum modulation and estimation of a real-valued random parameter, conveyed over an additive white Gaussian noise (AWGN) channel, where the performance metric is the large deviations behavior of the estimator, namely, the exponential decay rate (as a function of the observation time) of the probability that the estimation error would exceed a certain threshold. Our basic result is in providing an exact characterization of the fastest achievable exponential decay rate, among all possible modulator-estimator (transmitter-receiver) pairs, where the modulator is limited only in the signal power, but not in bandwidth. This exponential rate turns out to be given by the reliability function of the AWGN channel. We also discuss several ways to achieve this optimum performance, and one of them is based on quantization of the parameter, followed by optimum channel coding and modulation, which gives rise to a separation-based transmitter, if one views this setting from the perspectiv...

  1. A biogeography-based optimization for optimum discrete design of skeletal structures

    Science.gov (United States)

    Jalili, Shahin; Hosseinzadeh, Yousef; Taghizadieh, Nasser

    2016-09-01

    This article presents a modified biogeography-based optimization (MBBO) algorithm for optimum design of skeletal structures with discrete variables. The main idea of the biogeography-based optimization (BBO) algorithm is based on the science of biogeography, in which each habitat is a possible solution for the optimization problem in the search space. This algorithm consists of two main operators: migration and mutation. The migration operator helps the habitats to exploit the search space, while the mutation operator guides habitats to escape from the local optimum. To enhance the performance of the standard algorithm, some modifications are made and an MBBO algorithm is presented. The performance of the MBBO algorithm is evaluated by optimizing five benchmark design examples, and the obtained results are compared with other methods in the literature. The numerical results demonstrate that the MBBO algorithm is able to show very competitive results and has merits in finding optimum designs.

  2. On PID Controller Design by Combining Pole Placement Technique with Symmetrical Optimum Criterion

    Directory of Open Access Journals (Sweden)

    Viorel Nicolau

    2013-01-01

    Full Text Available In this paper, aspects of analytical design of PID controllers are studied, by combining pole placement technique with symmetrical optimum criterion. The proposed method is based on low-order plant model with pure integrator, and it can be used for both fast and slow processes. Starting from the desired closed-loop transfer function, which contains a second-order oscillating system and a lead-lag compensator, it is shown that the zero value depends on the real-pole value of closed-loop transfer function. In addition, there is only one pole value, which satisfies the assumptions of symmetrical optimum criterion imposed to open-loop transfer function. In these conditions, by combining the pole placement technique with symmetrical optimum criterion, the analytical expressions of the controller parameters can be simplified. For simulations, PID autopilot design for heading control problem of a conventional ship is considered.

  3. Optimum Design of Highway Excavation Slope Angle: Evidence from Dawu Section of Jingzhu Highway

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The optimum design of the highway excavation slope angle is one of the most important problems to the highway construction and to the slope improvement. The Dawu Section of Jingzhu (Beijing-Zhuhai) Highway is taken as an example to illustrate the study method for excavation slope angle design.The analysis of the engineering condition from different angles with different factors shows that the stability of the slope is calculated by using residual pushing force and the Sarma method. Then the sensitive analysis of the slope stability is conducted by using residual pushing force method. Finally, the optimum angle of design is presented on the precondition of ensuring the whole stability of slope and the economic reasonability. The study results show that the most sensitive factors are the shear strength parameter and t he seismic force, and that the optimum excavation slope angle is 60°.``

  4. Leaf blade and petiole nutritional diagnosis for Vitis vinifera L. cv. Tempranillo by deviation from optimum percentage method

    Directory of Open Access Journals (Sweden)

    Izaskun Romero

    2014-01-01

    Full Text Available Deviation from optimum percentage (DOP is a diagnosis methodology for leaf analyses which expresses the deviation for each element with respect to its optimal concentration. This deviation is an individual index for each nutrient and allows the sorting of all the analyzed nutrients according to their limitations. A nutritional survey was undertaken over eleven years in La Rioja (Spain, to establish reference concentrations for the nutritional diagnosis of Vitis vinifera L., cv. ‘Tempranillo’ grafted on Richter-110. Reference concentrations for DOP methodology are proposed, and sensibility for the nutritional diagnosis was evaluated for blade and petiole analysis of N, P, K, Ca, Mg, Fe, Mn, Zn, Cu, and B at flowering and veraison phenological stages by comparison between DOP and sufficiency ranges (SR methods. Results suggest that petiole has lower sensibility than blade to detect deficiencies or excesses of N, P, K, Ca, Mg, Zn, and Mn at veraison. In addition, petiole is a better tissue than blade to detect Fe and B deficiencies or excesses. Therefore, our results make possible the right choice between tissues, leaf blade or petiole, for a general nutritional diagnosis of ‘Tempranillo’ grapevines. On the other hand, it is possible to evaluate the status of each nutrient in each phonological stage analyzing both tissues and comparing the nutrient status to its references, DOP or SR, in the most adequate tissue.

  5. Adaptive Filters with Error Nonlinearities: Mean-Square Analysis and Optimum Design

    Directory of Open Access Journals (Sweden)

    Ali H. Sayed

    2001-01-01

    Full Text Available This paper develops a unified approach to the analysis and design of adaptive filters with error nonlinearities. In particular, the paper performs stability and steady-state analysis of this class of filters under weaker conditions than what is usually encountered in the literature, and without imposing any restriction on the color or statistics of the input. The analysis results are subsequently used to derive an expression for the optimum nonlinearity, which turns out to be a function of the probability density function of the estimation error. Some common nonlinearities are shown to be approximations to the optimum nonlinearity. The framework pursued here is based on energy conservation arguments.

  6. OPTIMUM PARAMETERS AND DESIGN OFTUNED MASS DAMPER FOR BUILDINGFRAMES UNDER GROUND ACCELERATION

    Institute of Scientific and Technical Information of China (English)

    李春祥

    2001-01-01

    For the purpose of comparison and applications, two criteria for the optimum searching are considered, which are the minimization of the minimum of the maximum dynamic magnification factor(Min. Min. Max. DMF) and the minimization of the minimum dynamic reduction factor (Min.Min.DRF). A study is carried out to investigate the applicability of designing TMD utilizing the unit modal participation factor. In addition, the design steps for the building frame with TMD are suggested. It is demonstrated that significant reduction in the response can be achieved by adopting the optimum TMD parameters in the present paper.

  7. Bi-Criteria System Optimum Traffic Assignment in Networks With Continuous Value of Time

    Directory of Open Access Journals (Sweden)

    Xin Wang

    2013-04-01

    Full Text Available For an elastic demand transportation network with continuously distributed value of time, the system disutility can be measured either in time units or in cost units. The user equilibrium model and the system optimization model are each formulated in two different criteria. The conditions required for making the system optimum link flow pattern equivalent to the user equilibrium link flow pattern are derived. Furthermore, a bi-objective model has been developed which minimizes simultaneously the system travel time and the system travel cost. The existence of a pricing scheme with anonymous link tolls which can decentralize a Pareto system optimum into the user equilibrium has been investigated.

  8. Optimum Performance-Based Seismic Design Using a Hybrid Optimization Algorithm

    Directory of Open Access Journals (Sweden)

    S. Talatahari

    2014-01-01

    Full Text Available A hybrid optimization method is presented to optimum seismic design of steel frames considering four performance levels. These performance levels are considered to determine the optimum design of structures to reduce the structural cost. A pushover analysis of steel building frameworks subject to equivalent-static earthquake loading is utilized. The algorithm is based on the concepts of the charged system search in which each agent is affected by local and global best positions stored in the charged memory considering the governing laws of electrical physics. Comparison of the results of the hybrid algorithm with those of other metaheuristic algorithms shows the efficiency of the hybrid algorithm.

  9. The Research on Selecting the Optimum Coefficient of Inharmonious Motion for the Front Wheel Assist Tractor

    Institute of Scientific and Technical Information of China (English)

    HuangXinghua; LinWumin

    1995-01-01

    Based on dynamic analysis for the Front Wheel Assist(FWA) tractor,a calculating and analysing method on selecting the optimum coefficient of inharmonious motion for the FWA tractor is described in this paper and the mathematical odels are also established.The article first time dlefines the ratio of thrust of front wheels to that of rear wheels.Which is an important parameter affeeting the tractive performance of the FWA tractor and establishes the conditon of no power circulation of the FWA tractor.The optimum coefficient of inharmonious motion for a FWA tractor (UTB-445)is also given.

  10. Compaction Filter as an Optimum Solution for Multirate Subband Coder of Cyclostationary Signals

    Directory of Open Access Journals (Sweden)

    D. Kula

    2003-09-01

    Full Text Available A consistent theory of optimum subband coding of zero meanwide-sense cyclostationary signals with N-periodic statistics ispresented in this paper. Blocked polyphase representation of theanalysis and synthesis filter banks is introduced as an effective wayof multirate subband coder description. Optimum energy compaction usingNyquist-M process is presented as a solution for maximizing the codinggain of the coder. In two definitions and four theorems the authorproves that Nyquist-M filters fulfill necessary and sufficientconditions imposed on subband signals. Results from Matlab simulationsare presented to support theoretical conclusions.

  11. The screening effects of carbon nanotube arrays and its field emission optimum density

    Directory of Open Access Journals (Sweden)

    Dan Cai

    2013-12-01

    Full Text Available In order to investigate the field emission optimum density of carbon nanotube (CNT array, the screening effects of CNT array have been studied. It has been shown that the electric field in the vicinity of an individual nanotube of array can be notable distorted due to the screening action of the surrounding neighbors. The optimum normalized spacing s/l(as referred to the length for the maximum emission current is inversely proportional to aspect ratio l/r and electric field strength for CNT arrays with a fixed dimension.

  12. Simulation of optimum parameters for GaN MSM UV photodetector

    Science.gov (United States)

    Alhelfi, Mohanad A.; Ahmed, Naser M.; Hashim, M. R.; Al-Rawi, Ali Amer; Hassan, Z.

    2016-07-01

    In this study the optimum parameters of GaN M-S-M photodetector are discussed. The evaluation of the photodetector depends on many parameters, the most of the important parameters the quality of the GaN film and others depend on the geometry of the interdigited electrode. In this simulation work using MATLAB software with consideration of the reflection and absorption on the metal contacts, a detailed study involving various electrode spacings (S) and widths (W) reveals conclusive results in device design. The optimum interelectrode design for interdigitated MSM-PD has been specified and evaluated by effect on quantum efficiency and responsivity.

  13. Approaches to optimum selection of space-planning and structural solutions of low-rise buildings

    Science.gov (United States)

    Gusakova, Natalya; Minaev, Nikolay; Filushina, Kristina; Gusakov, Alexander

    2017-01-01

    The paper is devoted to the development of approaches to optimum selection of space-planning and structural solutions of low-rise buildings for different kinds of territories. The aim of the study is to develop a system of criteria that influence the choice of optimum space-planning and structural solutions of buildings and structures aimed at enhancement of capital investment efficiency, energy and resource efficiency and creating comfortable living conditions for people. Developed solutions can be applied during implementation of investment construction projects of low-rise housing at different kinds of territories based on the local building materials.

  14. Optimum Tilt Angle for Photovoltaic Solar Panels in Zomba District, Malawi

    OpenAIRE

    B. Kamanga; Mlatho, J. S. P.; Mikeka, C.; C. Kamunda

    2014-01-01

    A study to determine the optimum tilt angle for installing photovoltaic solar panels in Zomba district, Malawi, has been conducted. The study determined the optimum monthly tilt angles of PV solar panels and the seasonal adjustments needed for the panels in order to collect maximum solar radiation throughout the year. In this study, global solar radiation (GSR) on four tilted surfaces was measured. The north-facing surfaces were titled at angles of 0°, 15°, 20°, and 25°. The GSR data was used...

  15. Cleaner concentrates

    Energy Technology Data Exchange (ETDEWEB)

    Boudechiche, S.; Hall, S. [University of Nottingham, Nottingham (United Kingdom)

    1995-06-01

    The desire for higher quality coal products in froth flotation has led to the introduction of a number of novel flotation techniques, including flotation columns, but the benefits of each in relation to the source of the slurry must be evaluated before plant is installed. It was to assess on a laboratory scale the quality of coal flotation concentrates from column flotation of fine coal (-500{mu}m) as an alternative to the traditional conventional agitated cell that this work was carried out. The column developed specifically for this purpose allowed the establishment of an approach to the examination of the flotation response of samples of UK coals (originating from Bolsover, Derbyshies; Rawdon, Leicestershire; and Bilsthorpe, Nottinghamshire). The work indicates the importance of the origin of the feed slurry, since each type of coal exhibits a different flotation response. The observations from the results described in this paper enable an assessment to be made of the merits of column flotation in fine coal treatment. 11 refs., 4 figs., 5 tabs.

  16. Finding the Optimum Scenario in Risk-benefit Assessment: An Example on Vitamin D

    DEFF Research Database (Denmark)

    Berjia, Firew Lemma; Hoekstra, J.; Verhagen, H.;

    2014-01-01

    Background: In risk-benefit assessment of food and nutrients, several studies so far have focused on comparison of two scenarios to weigh the health effect against each other. One obvious next step is finding the optimum scenario that provides maximum net health gains. Aim: This paper aims to sho...

  17. Analytical performance investigation of parabolic trough solar collector with computed optimum air gap

    Directory of Open Access Journals (Sweden)

    Devander Kumar, Sudhir Kumar

    2015-01-01

    Full Text Available Parabolic trough collectors have a wide range of industrial as well as domestic applications. This study analytically investigates the performance of non-evacuated absorber tube with glass cover of parabolic trough collector (PTC in terms of overall heat loss from the absorber. The impact of different parameters such as diameter of absorber tube, mean temperature of absorber tube, wind velocity, emissivity of absorber and ambient temperature have been studied and find the optimum value of air gap. The optimum value of air gap has been computed considering one-dimensional steady state model, where heat loss due to convection plus radiation is equal to heat loss due to conduction plus radiation from absorber tube to glass cover under steady state. Optimum air gap is found to be approximately 7mm and 8 mm for an absorber tube of diameter in range of 1.2-3.18cm and 4.5-7.62cm, respectively. Corresponding to optimum air gap, minimum overall heat loss has been observed. Overall heat loss increases with increase in absorber temperature, wind velocity and emissivity of absorber, whereas decreases with increase in air temperature for different absorber tube diameters. Absorber tube with diameters in the range of 3.18-4.5cm gives better performance. From the obtained data, correlations have been developed, which can be further utilized for designing the PTC system for getting desired output.

  18. Theory of optimum financial areas: retooling the debate on the governance of global finance

    NARCIS (Netherlands)

    Jones, E.; Underhill, G.

    2014-01-01

    This article examines the institutional preconditions for stable financial integration in a ‘theory of optimal financial areas’ (OFA). This theory is modelled on the theory of optimal currency areas that has been used to inform the process of monetary integration. Where it differs from optimum

  19. Pembuatan pupuk bokashi dari sampah lingkungan berdasarkan rancangan percobaan campuran yang optimum pada model permukaan multirespon

    Directory of Open Access Journals (Sweden)

    Ruslan Ruslan

    2012-02-01

    Full Text Available Environment waste arround ITS college such as waste of Trembesi leaves, Sono leaves, and Satintail at this research will be used as part of materials of Bokashi fertilizer producing. The first aim of this research produced Bokashi fertilizer in various proportion waste of Trembesi leaves, Sono leaves, and Satintail with other materials proportion which has been assumed to be constant based ondevelopment of optimum mixture design of multiresponse surface theory by D-optimum criterion. The second aim of this research was compared 5:3:1:1 composition from reference to 5:2:1:2 composition from researcher hypothesis with proportion of waste of Trembesi leaves, Sono leaves, and Satintail as independent variables to N, P, and K percentation as response variables. Optimum mixture designsof multiresponse surface model will be optimum if it weighted w = 1qs means the each point of experiment will be given s-replications as much as proportion number of experiment point to number of component. The 5:2:1:2 and 5:3:1:1 compositions of Bokashi fertilizer producing are not statistically difference, therefore both compositions can be used to produce Bokashi fertilizer.

  20. Optimum design of pultrusion process via evolutionary multi-objective optimization

    NARCIS (Netherlands)

    Tutum, Cem C.; Baran, Ismet; Deb, Kalyanmoy

    2014-01-01

    Pultrusion is one of the most cost-effective manufacturing techniques for producing fiber-reinforced composites with constant cross-sectional profiles. This obviously makes it more attractive for both researchers and practitioners to investigate the optimum process parameters, i.e., pulling speed, p

  1. Optimum condition-based maintenance policies for deteriorating systems with partial information

    NARCIS (Netherlands)

    Hontelez, J.A.M.; Burger, H.H.; Wijnmalen, D.J.D.

    1996-01-01

    Systems are considered which deteriorate as time goes on and whose conditions can be observed. The optimum maintenance policy with respect to cost is determined, based on a continuous deterioration process, by formulating the decision process as a discrete Markov decision problem. Examples from the

  2. Optimum contribution selection combined with weighting rare favourable alleles increases long-term genetic gain

    DEFF Research Database (Denmark)

    Liu, Huiming; Sørensen, Anders Christian; Berg, Peer

    simulated by combining GEBV or wGEBV and truncation selection (TS) or OCS. Optimum contribution selection was further categorized into OCSA and OCSG depending on whether pedigree (A) or genomic data (G) was used for penalizing average co-ancestry. The selection was performed for 40 generations. It was shown...

  3. Optimum design of pultrusion process via evolutionary multi-objective optimization

    DEFF Research Database (Denmark)

    Tutum, Cem Celal; Baran, Ismet; Deb, Kalyanmoy

    2014-01-01

    Pultrusion is one of the most cost-effective manufacturing techniques for producing fiber-reinforced composites with constant cross-sectional profiles. This obviously makes it more attractive for both researchers and practitioners to investigate the optimum process parameters, i.e., pulling speed...

  4. Analysis of the Optimum Usage of Slag for the Compressive Strength of Concrete.

    Science.gov (United States)

    Lee, Han-Seung; Wang, Xiao-Yong; Zhang, Li-Na; Koh, Kyung-Taek

    2015-03-18

    Ground granulated blast furnace slag is widely used as a mineral admixture to replace partial Portland cement in the concrete industry. As the amount of slag increases, the late-age compressive strength of concrete mixtures increases. However, after an optimum point, any further increase in slag does not improve the late-age compressive strength. This optimum replacement ratio of slag is a crucial factor for its efficient use in the concrete industry. This paper proposes a numerical procedure to analyze the optimum usage of slag for the compressive strength of concrete. This numerical procedure starts with a blended hydration model that simulates cement hydration, slag reaction, and interactions between cement hydration and slag reaction. The amount of calcium silicate hydrate (CSH) is calculated considering the contributions from cement hydration and slag reaction. Then, by using the CSH contents, the compressive strength of the slag-blended concrete is evaluated. Finally, based on the parameter analysis of the compressive strength development of concrete with different slag inclusions, the optimum usage of slag in concrete mixtures is determined to be approximately 40% of the total binder content. The proposed model is verified through experimental results of the compressive strength of slag-blended concrete with different water-to-binder ratios and different slag inclusions.

  5. Theory of optimum financial areas: retooling the debate on the governance of global finance

    NARCIS (Netherlands)

    Jones, E.; Underhill, G.

    2014-01-01

    This article examines the institutional preconditions for stable financial integration in a ‘theory of optimal financial areas’ (OFA). This theory is modelled on the theory of optimal currency areas that has been used to inform the process of monetary integration. Where it differs from optimum curre

  6. Supplier Portfolio Selection and Optimum Volume Allocation: A Knowledge Based Method

    NARCIS (Netherlands)

    Aziz, Romana; Hillegersberg, van Jos

    2010-01-01

    Selection of suppliers and allocation of optimum volumes to suppliers is a strategic business decision. This paper presents a decision support method for supplier selection and the optimal allocation of volumes in a supplier portfolio. The requirements for the method were gathered during a case stud

  7. Aridification in continental Asia after the Middle Eocene Climatic Optimum (MECO)

    NARCIS (Netherlands)

    Bosboom, R.E.; Abels, H.A.; Hoorn, C.; van den Berg, B.C.J.; Guo, Z.; Dupont-Nivet, G.

    2014-01-01

    Global climate cooling from greenhouse to icehouse conditions occurred across an enigmatic transitional interval during the Eocene epoch characterized by incipient polar ice-sheet formation as well as short-lived warming events, of which the Middle Eocene Climatic Optimum (MECO) is most noticeable.

  8. Optimum allocation of FACTS devices in Fars Regional Electric Network using genetic algorithm based goal attainment

    Institute of Scientific and Technical Information of China (English)

    Mohsen GITIZADEH; Mohsen KALANTAR

    2009-01-01

    This paper presents a novel approach to find optimum locations and capacity of flexible alternating current transmission system (FACTS) devices in a power system using a multi-objective optimization function. Thyristor controlled series compensators (TCSCs) and static var compensators (SVCs) are the utilized FACTS devices. Our objectives are active power loss reduction, newly introduced FACTS devices cost reduction, voltage deviation reduction, and increase on the robustness of thesecurity margin against voltage collapse. The operational and controlling constraints, as well as load constraints, were considered in the optimum allocation. A goal attainment method based on the genetic algorithm (GA) was used to approach the global optimum. The estimated annual load profile was utilized in a sequential quadratic programming (SQP) optimization sub-problem to the optimum siting and sizing of FACTS devices. Fars Regional Electric Network was selected as a practical system to validate the performance and effectiveness of the proposed method. The entire investment of the FACTS devices was paid offand an additional 2.4% savings was made. The cost reduction of peak point power generation implies that power plant expansion can be postponed.

  9. Early Eocene climatic optimum: Environmental impact on the North Iberian continental margin

    NARCIS (Netherlands)

    Payros, A.; Ortiz, S.; Millán, I.; Arostegi, J.; Orue-Etxebarria, X.; Apellaniz, E.

    2015-01-01

    The early Eocene climatic optimum, which constituted the peak of the long-term early Cenozoic global warming, had a significant impact on the environmental evolution of terrestrial and oceanic areas. Surprisingly, however, its influence on continental margins is poorly known. New insights are provid

  10. Optimum Parameters for Tuned Mass Damper Using Shuffled Complex Evolution (SCE Algorithm

    Directory of Open Access Journals (Sweden)

    Hessamoddin Meshkat Razavi

    2015-06-01

    Full Text Available This study is investigated the optimum parameters for a tuned mass damper (TMD under the seismic excitation. Shuffled complex evolution (SCE is a meta-heuristic optimization method which is used to find the optimum damping and tuning frequency ratio for a TMD. The efficiency of the TMD is evaluated by decreasing the structural displacement dynamic magnification factor (DDMF and acceleration dynamic magnification factor (ADMF for a specific vibration mode of the structure. The optimum TMD parameters and the corresponding optimized DDMF and ADMF are achieved for two control levels (displacement control and acceleration control, different structural damping ratio and mass ratio of the TMD system. The optimum TMD parameters are checked for a 10-storey building under earthquake excitations. The maximum storey displacement and acceleration obtained by SCE method are compared with the results of other existing approaches. The results show that the peak building response decreased with decreases of about 20% for displacement and 30% for acceleration of the top floor. To show the efficiency of the adopted algorithm (SCE, a comparison is also made between SCE and other meta-heuristic optimization methods such as genetic algorithm (GA, particle swarm optimization (PSO method and harmony search (HS algorithm in terms of success rate and computational processing time. The results show that the proposed algorithm outperforms other meta-heuristic optimization methods.

  11. Murray's law, the "Yarrum'" optimum, and the hydraulic architecture of compound leaves

    Science.gov (United States)

    Katherine A. McCulloh; John S. Sperry; Frederick C. Meinzer; Barbara Lachenbruch; Cristian. Atala

    2009-01-01

    There are two optima for maximizing hydraulic conductance per vasculature volume in plants. Murray's law (ML) predicts the optimal conduit taper for a fixed change in conduit number across branch ranks. The opposite, the Yarrum optimum (YO), predicts the optimal change in conduit number for a fixed taper. We derived the solution for YO and then evaluated...

  12. Position Analysis of a Pico-Satellite for Optimum Solar Illumination

    Science.gov (United States)

    Ramirez, F. M.

    2014-06-01

    This study characterizes the attitude of a satellite in order to obtain the optimum solar illumination on the face of a solar panel. While taking into consideration times of eclipse, a curve for the area exposed to the sun is derived.

  13. Determination of Solar Collector Optimum Tilt Angle for Ankara and Districts

    Directory of Open Access Journals (Sweden)

    Abdülkadir KOÇER

    2016-04-01

    Full Text Available This study that is Ankara province and districts based deals with the determination of the optimum tilt angle to maximize the performances of solar collector and solar panel. In Ankara, fixed solar collectors are usually placed at slope of 40°. In this study, annual optimum tilt angle for Ankara province and districts was calculated as 34°±1 however the optimum angles during the year were calculated between 1° and 67°. The results of this study are compared with similar studies in the literature they were found to be consistent with the results of similar studies. Also, the tilt angle was calculated for the six months periods as 15° and 56°, for seasonal periods (winter, spring, summer, autumn as 62°, 23°, 6° and 49°, respectively and solar radiation for optimum angles of inclination were found. When the tilt angle is changed only twice a year, due to increasing the amount of energy per unit area, according to the annual tilt angle fixed product they provides energy efficiency by about 5%. On the other hand, when the tilt angle is changed every month this ratio can be reached approximately 8%. For increasing the utilization efficiency of solar collectors and panels, it is recommended adjusting of the tilt angle once a month or at least twice a year.

  14. High resolution or optimum resolution? Spatial analysis of the Federmesser site at Andernach, Germany

    NARCIS (Netherlands)

    Stapert, D; Street, M

    1997-01-01

    This paper discusses spatial analysis at site level. It is suggested that spatial analysis has to proceed in several levels, from global to more detailed questions, and that optimum resolution should be established when applying any quantitative methods in this field. As an example, the ring and sec

  15. The optimum energy harvest efficiency of nitrogen fixing hydrophyte: Azolla pinnata

    Energy Technology Data Exchange (ETDEWEB)

    Tennakone, K. (Institute of Fundamental Studies, Kandy (LK) Ruhuna Univ., Matara (LK). Dept. of Physics); Punchihewa, S.; Jayasuriya, A.C. (Institute of Fundamental Studies, Kandy (LK))

    1989-01-01

    Azolla is a nitrogen fixing hydrophyte that can be cultivated in absence of nitrogenous fertilizer. It is found that when biomass is continuously harvested from a culture of Azolla, solar energy can be converted at an optimum efficiency of 1.1%. (author).

  16. Some Optimum and Suboptimum Frame Synchronizers for Binary Data in Gaussian Noise

    DEFF Research Database (Denmark)

    Nielsen, Palle Tolstrup

    1973-01-01

    In this correspondence we investigate the performance of several optimum and suboptimum devices for locating a sync word in data corrupted by Gaussian noise. One suboptimum synchronizer, which is extremely simple to instrument, is shown to perform virtually optimally over the entire range...

  17. Identification of Optimum Location of STATCOM in Transmission Line Employing RCGA Optimization Technique

    Directory of Open Access Journals (Sweden)

    A.D. Falehi

    2012-07-01

    Full Text Available This study inspects the optimum location of STATCOM device in long transmission line to acquire the maximum power system transient stability improvement. STATCOM is a kind of prominent and effective shunt FACTS device which is used in power system to enhance the power system stability and to regulate the line voltage. When it has been placed at the center point of a transmission line, play a key role in controlling the reactive power flow and enhancing the power system transient stability. The active power losses caused by transmission line resistance alter the neutral position or optimum location of STATCOM in transmission line. RCGA optimization due to have high ability to solve non-linear objective function has been implanted to identify the optimum location of STATCOM. The results of non-linear simulation under severe disturbance approve that the optimum location of STATCOM in order to access the maximum power system transient stability by reducing the active power losses approaches to midpoint of transmission line.

  18. Aridification in continental Asia after the Middle Eocene Climatic Optimum (MECO)

    NARCIS (Netherlands)

    Bosboom, R.E.; Abels, H.A.; Hoorn, C.; van den Berg, B.C.J.; Guo, Z.; Dupont-Nivet, G.

    2014-01-01

    Global climate cooling from greenhouse to icehouse conditions occurred across an enigmatic transitional interval during the Eocene epoch characterized by incipient polar ice-sheet formation as well as short-lived warming events, of which the Middle Eocene Climatic Optimum (MECO) is most noticeable.

  19. Calculating Optimum sowing factor: A tool to evaluate sowing strategies and minimize seedling production cost

    Science.gov (United States)

    Eric van Steenis

    2013-01-01

    This paper illustrates how to use an excel spreadsheet as a decision-making tool to determine optimum sowing factor to minimize seedling production cost. Factors incorporated into the spreadsheet calculations include germination percentage, seeder accuracy, cost per seed, cavities per block, costs of handling, thinning, and transplanting labor, and more. In addition to...

  20. Compositional Optimum Design and Experimental Investigation of Rare Earth Containing Ceramic Composite

    Institute of Scientific and Technical Information of China (English)

    Xu Chonghai; Huang Chuanzhen; Ai Xing

    2004-01-01

    Based on the Al2O3/(W,Ti) C ceramic material, optimum design of the material compositions were carried out, which includes the theoretical calculation of the critical volume fraction of the reinforcement phase, and the optimum design based on the impact resistance, thermal shock resistance and wear resistance, etc. It is found that the optimum volume fraction of (W,Ti)C is 31.2%, 32.8% and 34%, respectively, which is corresponding with the best impact resistance, thermal shock resistance and wear resistance. After comprehensive consideration, the optimum volume fraction of (W,Ti)C in Al2O3/( W, Ti)C ceramic material is finally determined to be 30%. Then, effects of the content of rare earth yttrium on the mechanical property of the Al2O3/30vol% (W,Ti)C ceramic material were investigated experimentally. It indicates that when the content of yttrium is 0.25% ~ 0.5%, both flexural strength and fracture toughness of the rare earth containing ceramic material are further improved with the increment of approximately 10% ~16%.

  1. Questions on optimum utilization of modified bioadsorbents for adsorption of cadmium ions

    OpenAIRE

    MAMEDOVA SEADET OSMAN GIZI

    2015-01-01

    Two modifications of compound additive criteria have been suggested where the first component represents the conditions to reach the maximum quantity of adsorbate in adsorbent, and the second one represents the total expenditure for all adsorption process. It is shown, that the suggested criterion has an extremum property and make it possible to determine the optimum characteristics of adsorption.

  2. Cryogenic current comparators with optimum SQUID readout for current and resistance quantum metrology

    NARCIS (Netherlands)

    Bartolomé Porcar, María Elena

    2002-01-01

    This thesis describes the development of several systems based on the Cryogenic Current Comparator with optimum SQUID readout, for current and resistance metrology applications. the CCC-SQUID is at present the most accurate current comparator available. A (type I) CCC consists basically of a

  3. 41 CFR 102-75.55 - What does the term “Not being put to optimum use” mean?

    Science.gov (United States)

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What does the term âNot being put to optimum useâ mean? 102-75.55 Section 102-75.55 Public Contracts and Property Management... “Not being put to optimum use” mean? Not being put to optimum use means an entire property or...

  4. Color removal from distillery spent wash through coagulation using Moringa oleifera seeds: use of optimum response surface methodology.

    Science.gov (United States)

    Prasad, R Krishna

    2009-06-15

    The effects of dosage, pH and concentration of salts were investigated for an optimized condition of color removal from the distillery spent wash. The optimization process was analyzed using custom response surface methodology (RSM). The design was employed to derive a statistical model for the effect of parameters studied on removal of color using Moringa oleifera coagulant (MOC). The dosage (20 and 60 ml), pH (7 and 8.5) and concentration of 0.25 M had been found to be the optimum conditions for maximum 56% and 67% color removal using sodium chloride (NaCl) and potassium chloride (KCl) salts respectively. The actual color removal at optimal conditions was found to be 53% and 64% respectively for NaCl and KCl salts which confirms close to RSM results. The effects of storage duration and temperature on MOC studied reveal that coagulation efficiency of MOC kept at room temperature was effective for 3 days and at 4 degrees C it performed coagulation up to 5 days.

  5. Determining the Optimum Exposure and Recovery Periods for Efficient Operation of a QCM Based Elemental Mercury Vapor Sensor

    Directory of Open Access Journals (Sweden)

    K. M. Mohibul Kabir

    2015-01-01

    Full Text Available In recent years, mass based transducers such as quartz crystal microbalance (QCM have gained huge interest as potential sensors for online detection of elemental mercury (Hg0 vapor from anthropogenic sources due to their high portability and robust nature enabling them to withstand harsh industrial environments. In this study, we determined the optimal Hg0 exposure and recovery times of a QCM based sensor for ensuring its efficient operation while monitoring low concentrations of Hg0 vapor (<400 ppbv. The developed sensor was based on an AT-cut quartz substrate and utilized two gold (Au films on either side of the substrate which functions as the electrodes and selective layer simultaneously. Given the temporal response mechanisms associated with mass based mercury sensors, the experiments involved the variation of Hg0 vapor exposure periods while keeping the recovery time constant following each exposure and vice versa. The results indicated that an optimum exposure and recovery periods of 30 and 90 minutes, respectively, can be utilized to acquire the highest response magnitudes and recovery rate towards a certain concentration of Hg0 vapor whilst keeping the time it takes to report an accurate reading by the sensor to a minimum level as required in real-world applications.

  6. Optimum Detection of Ultrasonic Echoes Applied to the Analysis of the First Layer of a Restored Dome

    Directory of Open Access Journals (Sweden)

    Addisson Salazar

    2007-01-01

    Full Text Available Optimum detection is applied to ultrasonic signals corrupted with significant levels of grain noise. The aim is to enhance the echoes produced by the interface between the first and second layers of a dome to obtain interface traces in echo pulse B-scan mode. This is useful information for the restorer before restoration of the dome paintings. Three optimum detectors are considered: matched filter, signal gating, and prewhitened signal gating. Assumed models and practical limitations of the three optimum detectors are considered. The results obtained in the dome analysis show that prewhitened signal gating outperforms the other two optimum detectors.

  7. Optimum Repartition of Transport Capacities in the Logistic System using Dynamic Programming

    Directory of Open Access Journals (Sweden)

    Gheorghe BĂŞANU

    2011-08-01

    Full Text Available Transportations take an essential role in logistics, interconnecting the majority of processes and operations within logistic system. The efficient use of transportation capacity is a priority whose achievement can diminish logistic costs. This objective is today difficult to achieve due to increasing complexity of transportation monitoring and coordination. This complexity is determined by transportation number and diversity, by the volume and diversity of orders, by increasing the targets to be supplied.Dynamic programming represents a highly useful tool for logistic managers, considering that its specific techniques and methods are oriented toward solving problems related to resource optimum allocation and utilization.The present paper presents briefly a series of theoretical elements of dynamic programming applied in logistics, based on which it is shown a mathematic model to determine the optimum policy for transport capacity repartition for the area attached to a logistic centre, through three distribution centres.

  8. Optimum surface roughness prediction for titanium alloy by adopting response surface methodology

    Science.gov (United States)

    Yang, Aimin; Han, Yang; Pan, Yuhang; Xing, Hongwei; Li, Jinze

    Titanium alloy has been widely applied in industrial engineering products due to its advantages of great corrosion resistance and high specific strength. This paper investigated the processing parameters for finish turning of titanium alloy TC11. Firstly, a three-factor central composite design of experiment, considering the cutting speed, feed rate and depth of cut, are conducted in titanium alloy TC11 and the corresponding surface roughness are obtained. Then a mathematic model is constructed by the response surface methodology to fit the relationship between the process parameters and the surface roughness. The prediction accuracy was verified by the one-way ANOVA. Finally, the contour line of the surface roughness under different combination of process parameters are obtained and used for the optimum surface roughness prediction. Verification experimental results demonstrated that material removal rate (MRR) at the obtained optimum can be significantly improved without sacrificing the surface roughness.

  9. Analytical upper bound on optimum joint decoding capacity of Wyner GCMAC using hadamard inequality

    KAUST Repository

    Shakir, Muhammad

    2011-11-01

    This paper presents an original analytical expression for an upper bound on the optimum joint decoding capacity of Wyner circular Gaussian cellular multiple access channel (C-GCMAC) for uniformly distributed mobile terminals (MTs) across the cells. This upper bound is referred to as Hadamard upper bound (HUB) and is a novel application of the Hadamard inequality established by exploiting the Hadamard operation between the channel fading and channel path gain matrices. In this context, we employ an approximation approach based on the estimation of probability density function (PDF) of Hadamard product of two matrices. A closed-form expression has been derived to capture the effect of variable user density in adjacent cells on optimal joint decoding capacity. The results of this paper demonstrate that the analytical HUB based on the proposed approximation approach converges to the theoretical results for medium range of signal to noise ratios and shows a comparable tighter bound on optimum joint decoding capacity. © 2011 IEEE.

  10. Optimum design and layout of the cooling apparatus for long compaignship blast furnace

    Institute of Scientific and Technical Information of China (English)

    Shusen Cheng; Tianjun Yang; Qingguo Xue; Haibin Zuo; Xiaowu Gao; Weiguo Yang

    2003-01-01

    Generally, the cooler life can determine the blast furnace life. The slag-metal skull frozen on the cooler can separate the cooler from the hot gas flow in blast furnace. The key problem is how to freeze liquid slag-metal on the cooler, and the main measure is to decrease the hot surface temperature of the cooler. The computational technology of heat transfer was practically used for long campaign blast furnace design. The optimum design of the cast iron stave, copper stave, plate-stave combined system and flangestave was given by the computing results. According to the results, the optimum arrangement of different coolers (cast iron or copper stave, flange stave and plate-stave combined system) on different height of blast furnace wall can be found through all these temperature fields.

  11. Effect of Thread Level Parallelism on the Performance of Optimum Architecture for Embedded Applications

    CERN Document Server

    Alipour, Mehdi

    2012-01-01

    According to the increasing complexity of network application and internet traffic, network processor as a subset of embedded processors have to process more computation intensive tasks. By scaling down the feature size and emersion of chip multiprocessors (CMP) that are usually multi-thread processors, the performance requirements are somehow guaranteed. As multithread processors are the heir of uni-thread processors and there isn't any general design flow to design a multithread embedded processor, in this paper we perform a comprehensive design space exploration for an optimum uni-thread embedded processor based on the limited area and power budgets. Finally we run multiple threads on this architecture to find out the maximum thread level parallelism (TLP) based on performance per power and area optimum uni-thread architecture.

  12. Dynamic model for population distribution and optimum immigration and job creation policies

    Directory of Open Access Journals (Sweden)

    N. U. Ahmed

    2004-12-01

    Control theory, it is possible to formulate optimum immigration and job creation strategies while maintaining population level close to certain pre-specified targets. With this objective in mind, we consider a simplified dynamic model based on a previous model developed in (Ahmed and Rahim, 2001:325-358 to describe the population distribution in Canada. Numerical results demonstrate that the model population is in close agreement with the actual population. This model was then used to formulate a control problem with immigration and job creation rates being the decision (control variables. Using optimal control theory, optimum immigration and job creation policies were determined. Results are illustrated by numerical simulation and they are found to be very encouraging.

  13. Dynamic model for population distribution and optimum immigration and job creation policies

    Directory of Open Access Journals (Sweden)

    Ahmed, N.U.

    2004-01-01

    Full Text Available In this paper we demonstrate that by use of modern Systems and Optimal Control theory, it is possible to formulate optimum immigration and job creation strategies while maintaining population level close to certain pre-specified targets. With this objective in mind, we consider a simplified dynamic model based on a previous model developed in (Ahmed and Rahim, 2001:325-358 to describe the population distribution in Canada. Numerical results demonstrate that the model population is in close agreement with the actual population. This model was then used to formulate a control problem with immigration and job creation rates being the decision (control variables. Using optimal control theory, optimum immigration and job creation policies were determined. Results are illustrated by numerical simulation and they are found to be very encouraging.

  14. A literature review on optimum and preferred joint angles in automotive sitting posture.

    Science.gov (United States)

    Schmidt, Susanne; Amereller, Maximilian; Franz, Matthias; Kaiser, Ralf; Schwirtz, Ansgar

    2014-03-01

    In this study, a survey of the scientific literature in the field of optimum and preferred human joint angles in automotive sitting posture was conducted by referring to thirty different sources published between 1940 and today. The strategy was to use only sources with numerical angle data in combination with keywords. The aim of the research was to detect commonly used joint angles in interior car design. The main analysis was on data measurement, usability and comparability of the different studies. In addition, the focus was on the reasons for the differently described results. It was found that there is still a lack of information in methodology and description of background. Due to these reasons published data is not always usable to design a modern ergonomic car environment. As a main result of our literature analysis we suggest undertaking further research in the field of biomechanics and ergonomics to work out scientific based and objectively determined "optimum" joint angles in automotive sitting position.

  15. ABC Supported Handover Decision Scheme based on multi-PSO with Optimum Mutation

    Directory of Open Access Journals (Sweden)

    Xingwei Wang

    2011-08-01

    Full Text Available In this paper, a handover decision scheme with ABC (always best connected supported is proposed. With knowledge of fuzzy mathematics and microeconomics introduced, application types, QoS (quality of service requirements, access networks and terminals are described. With access network conditions, application requirements, user preferences to access network coding schemes, user preferences to access network providers, terminal velocities and terminal battery capacities considered comprehensively, an optimal handover solution of assigning N terminals to M access networks is found based on multi-PSO (particle swarm optimization with optimum mutation. With the help of gaming analysis, Pareto optimum under Nash equilibrium of both user utility and network provider utility is achieved or approached for the found solution. Simulation results showed that it was effective.

  16. An Optimum Analysis Method of Sandwich Structures Made from Elastic-viscoelastic Materials

    Institute of Scientific and Technical Information of China (English)

    CHEN Ying-bo; XIA Yu; REN Zhi-gang; LU Zhe-an; WANG Er-lei

    2004-01-01

    Due to a viscoelastic damping middle layer,sandwich structures have the capacity of energy consumption.In this paper,we describe the frequency-dependent property of viscoelastic materials using complex modulus model,and iterative modal strain energy method and iterative complex eigenvalue method are presented to obtain frequency and loss factor of sandwich structures.The two methods are effective and exact for the large-scale complex composite sandwich structures.Then an optimum analysis method is suggested to apply to sandwich structures.Finally,as an example,an optimum analysis of a clamped-clamped sandwich beams is conducted,theoretical closed-form solution and numerical predictions are studied comparatively,and the results agree well.

  17. An iterative method for obtaining the optimum lightning location on a spherical surface

    Science.gov (United States)

    Chao, Gao; Qiming, MA

    1991-01-01

    A brief introduction to the basic principles of an eigen method used to obtain the optimum source location of lightning is presented. The location of the optimum source is obtained by using multiple direction finders (DF's) on a spherical surface. An improvement of this method, which takes the distance of source-DF's as a constant, is presented. It is pointed out that using a weight factor of signal strength is not the most ideal method because of the inexact inverse signal strength-distance relation and the inaccurate signal amplitude. An iterative calculation method is presented using the distance from the source to the DF as a weight factor. This improved method has higher accuracy and needs only a little more calculation time. Some computer simulations for a 4DF system are presented to show the improvement of location through use of the iterative method.

  18. [Formation of optimum dose fields in contact radiation therapy of malignant tumors].

    Science.gov (United States)

    Klepper, L Ia

    2003-01-01

    The definition of the homogeneity of a dose field in the contact radiation therapy for malignant tumors is introduced. The mathematical interpretation of problems in the formation of optimum dose fields, to which the maximum homogeneity of a dose field at the site of lesion corresponds, is presented. It is shown that the problems in the formation of optimum dose fields may be divided into two subsets in relation to whether the sources of radiation are located at the site of lesion or adjacent to the latter (application techniques of radiation). An analytical method for solving a problem in the formation of an optimal dose field in the ring circle by means of one ring source of radiation (the first type of problems). The investigation was conducted with the support of the Russian Fund of Fundamental Investigations (RFFI 01-01-00137).

  19. Optimum Design of Multi-Function Robot Arm Gripper for Varying Shape Green Product

    Directory of Open Access Journals (Sweden)

    Razali Zol Bahri

    2016-01-01

    Full Text Available The project focuses on thorough experimentally studies of the optimum design of Multi-function Robot Arm Gripper for varying shape green product. The purpose of this project is to design a few of robot arm gripper for multi-functionally grip a green product with varying shape. The main character of the gripper is that it can automated adjust its finger to suit with the shape of the product. An optimum design of multi-function robot arm gripper is verified through experimental study. The expected result is a series of analytical results on the proposal of gripper design and material that will be selected for the gripper. The analysis of the gripper design proposal by using ANSYS and CATIA software is described in detail in this paper.

  20. Determining the optimum topology of composites by the flexural stiffness criterion

    Directory of Open Access Journals (Sweden)

    Vasile MOGA

    2012-06-01

    Full Text Available An important stage in designing of pieces made of composite materials consists of establishing the composite topology in such a way that it has certain properties needed in exploitation. The paper presents the mathematical apparatus and the calculation programme for establishing the optimum thickness of the composite groups so that it should have certain imposed (given flexural stiffness. The method is applicable to all types of laminate composites, no matter of the cladding or matrix nature. The direct problem consists in determining the thickness of the groups and composite, minimising the bar mass, for an imposed (given flexural stiffness, knowing the densities and elasticity modules of the groups. The indirect problem consists in determining the maximum stiffness, the thickness of the groups and composite for a given (imposed mass, knowing the densities and elasticity modules of the groups. The presented programmes offer to the producer of this kind of materials the possibility to quickly establish the optimum topology.

  1. PENENTUAN WAKTU KONTAK DAN pH OPTIMUM PENYERAPAN METILEN BIRU MENGGUNAKAN ABU SEKAM PADI

    Directory of Open Access Journals (Sweden)

    Anung Riapanitra

    2006-11-01

    Full Text Available Dyes are widely used for colouring in textile industries, significant losses occur during the manufacture and processing of the product, and these lost chemical are discharged in surrounding effluent. Adsorption of dyes is an effective technology for treatment of wastewater contaminated by the mismanaged of different types of dyes. In this research, we investigated the potential of rice husk ash for removal of methylene blue dyeing agent in aqueous system. The aim of this research is to find out the optimum contact time and pH on the adsorption of methylene blue using rice husk ash. Batch kinetics studies were carried out under varying experimental condition of contact time and pH. An adsorption equilibrium condition was reached within 10 minutes and the optimum condition for adsorption was at pH 3. The adsorption of methylene blue was decreasing with decreasing the solution pH value.

  2. Optimum metallic-bond scheme: Theoretical study ofgeometric structures for ground-state sodium clusters

    Institute of Scientific and Technical Information of China (English)

    苏长荣; 李家明

    2002-01-01

    We present an optimum metallic-bond scheme to study the geometric structures of sodium clusters Nan (n≤15) systematically by combining the characteristics of metallic bonds and the first principle molecular dynamics simulation. The scheme provides an optimum way to examine almost all stable structures of sodium clusters and to determine their ground state structures. It is interesting to note that for the larger sodium clusters (13≤n≤15), there are some plane-like substructures on their surfaces, which resemble the fragments of the (110) plane with the highest atomic area density in the bulk bcc sodium crystal. We also propose a possible way to understand the formation of large icosahedral sodium clusters (1500<n<22000).

  3. PID controller auto-tuning based on process step response and damping optimum criterion.

    Science.gov (United States)

    Pavković, Danijel; Polak, Siniša; Zorc, Davor

    2014-01-01

    This paper presents a novel method of PID controller tuning suitable for higher-order aperiodic processes and aimed at step response-based auto-tuning applications. The PID controller tuning is based on the identification of so-called n-th order lag (PTn) process model and application of damping optimum criterion, thus facilitating straightforward algebraic rules for the adjustment of both the closed-loop response speed and damping. The PTn model identification is based on the process step response, wherein the PTn model parameters are evaluated in a novel manner from the process step response equivalent dead-time and lag time constant. The effectiveness of the proposed PTn model parameter estimation procedure and the related damping optimum-based PID controller auto-tuning have been verified by means of extensive computer simulations.

  4. Optimum profile modifications of spur gears by means of genetic algorithms

    Science.gov (United States)

    Bonori, Giorgio; Barbieri, Marco; Pellicano, Francesco

    2008-06-01

    An original application of Genetic Algorithms (GAs) is developed in order to optimize spur gear pairs toward vibration and noise reduction. The approach takes into account the most important parameters of micro-geometric modifications, namely tip and root relief, therefore the parameter space is eight dimensional. The objective function of the GA depends on the static transmission error (STE) that is related to teeth flexibility. STE is estimated by means of a nonlinear finite element approach: either the amplitude of the STE fluctuation or its harmonic content are considered as objective functions. The effectiveness of the approach is checked on an actual test case: GAs are able to find the optimum after a reasonable number of steps; such optimum is obtained on static basis and gives a strong vibration reduction. The reliability test proves that GAs lead to robust optima.

  5. A review on synchronous CDMA systems: optimum overloaded codes, channel capacity, and power control

    Directory of Open Access Journals (Sweden)

    Hosseini Seyed Amirhossein

    2011-01-01

    Full Text Available Abstract This paper is a tutorial review on important issues related to code-division multiple-access (CDMA systems such as channel capacity, power control, and optimum codes; specifically, we consider optimum overloaded codes that achieve errorless transmission in the absence of noise for the binary and nonbinary cases. A survey of lower and upper bounds for the sum channel capacity of such systems is given in the presence and absence of channel noise. The asymptotic results for the channel capacity are also investigated. The channel capacity, errorless transmission codes, and power estimation for near-far effects are also explored. The emphasis of this tutorial review is on the overloaded CDMA systems.

  6. Optimum principle for a vehicular traffic network: minimum probability of congestion

    Science.gov (United States)

    Kerner, Boris S.

    2011-03-01

    We introduce an optimum principle for a vehicular traffic network with road bottlenecks. This network breakdown minimization (BM) principle states that the network optimum is reached when link flow rates are assigned in the network in such a way that the probability for spontaneous occurrence of traffic breakdown in at least one of the network bottlenecks during a given observation time reaches the minimum possible value. Based on numerical simulations with a stochastic three-phase traffic flow model, we show that in comparison to the well-known Wardrop's principles, the application of the BM principle permits considerably greater network inflow rates at which no traffic breakdown occurs and, therefore, free flow remains in the whole network.

  7. The Estimate of the Optimum Number of Retail Stores of Small Market Areas Using Agent Model

    Science.gov (United States)

    Tajima, Takuya; Hibino, Takayuki; Abe, Takehiko; Kimura, Haruhiko

    At present, the conditions of the location and the optimal arrangements for retail stores of small market areas are examined with the several surveys. The surveys are important because the proceeds are influenced largely with the selection of the location. However, costs, time and experience are necessary in the surveys. For this reason, this research is intended for the retail stores of small market areas which expend a great deal of money for the surveys. The retail stores of small market areas in this paper are convenience stores. The purpose of this paper is to estimate the optimum number of convenience stores by computer simulation. We adopted the agent model. We constructed an agent model that had the customer agent, the shop agent and the landscape with the kind of necessary minimum parameters. And, we were able to make the simulation environment that reflected the real world. As a result, we could estimate the optimum number of convenience stores by simulations.

  8. Optimum NOx abatement in diesel exhaust using inferential feedforward reductant control

    Energy Technology Data Exchange (ETDEWEB)

    Krijnsen, H.C.; Leeuwen, J.C.M. van; Bakker, R.; Bleek, C.M. van den; Calis, H.P.A. [Delft University of Technology, Delft (Netherlands). DelftChem Tech, Faculty of Applied Sciences, Chemical Reactor Engineering

    2001-05-01

    To adequately control the reductant flow for the selective catalytic reduction of NOx in diesel exhaust gas a tool is required that is capable of accurately and quickly predicting the engine's fluctuating NOx emissions based on its time-dependent operating variables, and that is also capable of predicting the optimum reductant/NOx ratio for NOx abatement. Measurements were carried out on a semi-stationary diesel engine. Four algorithms for non-linear modelling are evaluated. The models resulting from the algorithms gave very accurate NOx predictions with a short computation time. Together with the small errors this makes the models very promising tools for on-line automotive NOx emission control. The optimum reductant/NOx ratio (to get the lowest combined NOx + reduction emission of the exhaust treating system) was best predicted by a neural network. 24 refs., 6 figs., 5 tabs.

  9. On optimum strategies for minimizing the exponential moments of a given cost function

    CERN Document Server

    Merhav, Neri

    2011-01-01

    We consider a general problem of finding a strategy that minimizes the exponential moment of a given cost function, with an emphasis on its relation to the more common criterion of minimization the expectation of the first moment of the same cost function. In particular, our main result is a theorem that gives simple sufficient conditions for a strategy to be optimum in the exponential moment sense. This theorem may be useful in various situations, and application examples are given. We also examine the asymptotic regime and investigate universal asymptotically optimum strategies in light of the aforementioned sufficient conditions, as well as phenomena of irregularities, or phase transitions, in the behavior of the asymptotic performance, which can be viewed and understood from a statistical-mechanical perspective. Finally, we propose a new route for deriving lower bounds on exponential moments of certain cost functions (like the square error in estimation problems) on the basis of well known lower bounds on...

  10. Optimum Envelope of a Single-Family House Based on Life Cycle Analysis

    Directory of Open Access Journals (Sweden)

    Marie-Claude Hamelin

    2014-04-01

    Full Text Available This paper describes the methodology used for the life cycle cost (LCC and life cycle energy (LCE analyses of the case study house in Quebec, Canada. The TRNSYS energy analysis program is coupled with GenOpt, a general purpose optimization program, for the purpose of this study. The particle swarm optimization (PSO algorithm is used for the search for the optimum solution. Results show that the optimum levels of insulation should be higher than the reference values, even for the case of LCC analysis. The results are for the most part still valid if electricity costs are assumed to increase below the inflation rate for the duration of the study period.

  11. An Optimum Method for a Grooved 2D Planar Ion Trap Design

    Institute of Scientific and Technical Information of China (English)

    JI Wei-Bang; WAN Jin-Yin; CHENG Hua-Dong; LIU Liang

    2011-01-01

    We investigate an effective grooved 2D ion chip design and optimize the ratio between the size of the rf electrodes and the groove.We calculate the optimal size of the groove using the analyticai model,which was introduced by House,and the optimum result is obtained. We aiso obtain the simulated scattering points with the finite element analysis method.The analytical curve and simulated scattering points are coincident with each other.It is shown that this analytical model also fits for the grooved planar ion chip.Thus the optimum grooved 2D planar ion chip design could be obtained.It is effective for scalable quantum information processing.

  12. ORPOM model for optimum distribution of tree ring sampling based on the climate observation network

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Tree ring dating plays an important role in obtaining past climate information.The fundamental study of obtaining tree ring samples in typical climate regions is particularly essential.The optimum distribution of tree ring sampling sites based on climate information from the Climate Observation Network(ORPOM model) is presented in this article.In this setup,the tree rings in a typical region are used for surface representation,by applying excellent correlation with the climate information as the main principle.Taking the Horqin Sandy Land in the cold and arid region of China as an example,the optimum distribution range of the tree ring sampling sites was obtained through the application of the ORPOM model,which is considered a reasonably practical scheme.

  13. Optimum bolus wizard settings in insulin pumps in children with Type 1 diabetes

    DEFF Research Database (Denmark)

    Andersen, A J B; Ostenfeld, A; Pipper, C B

    2016-01-01

    AIM: To evaluate current insulin pump settings in an optimally regulated paediatric population using bolus wizard. METHODS: We used a retrospective study design to analyse data from 124 children on insulin pump therapy who had optimum HbA1c levels [.... Furthermore, duration of insulin pump treatment was significantly associated with insulin sensitivity factor and percentage bolus/basal was significantly associated with insulin to carbohydrate factor. Gender, diabetes duration and BMI were not associated with any of the calculation factors. CONCLUSION......: Optimum insulin pump settings at pump initiation depend on both insulin requirements and use of the pump. Settings need to be individualized because the standardized calculation factors are not constant for children. There is a need to develop specific age- and insulin dose-dependent calculation factors....

  14. Optimum Design of LLC Resonant Converter using Inductance Ratio (Lm/Lr)

    Science.gov (United States)

    Palle, Kowstubha; Krishnaveni, K.; Ramesh Reddy, Kolli

    2016-07-01

    The main benefits of LLC resonant dc/dc converter over conventional series and parallel resonant converters are its light load regulation, less circulating currents, larger bandwidth for zero voltage switching, and less tuning of switching frequency for controlled output. An unique analytical tool, called fundamental harmonic approximation with peak gain adjustment is used for designing the converter. In this paper, an optimum design of the converter is proposed by considering three different design criterions with different values of inductance ratio (Lm/Lr) to achieve good efficiency at high input voltage. The optimum design includes the analysis in operating range, switching frequency range, primary side losses of a switch and stability. The analysis is carried out with simulation using the software tools like MATLAB and PSIM. The performance of the optimized design is demonstrated for a design specification of 12 V, 5 A output operating with an input voltage range of 300-400 V using FSFR 2100 IC of Texas instruments.

  15. Optimum operation conditions of nitrogen and phosphorus removal by a biofilm-activated-sludge system

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    In the biofilm and activated sludge combined system, denitrifying bacteria attached on the fibrous carriers in the anoxic tank, while the sludge containing nitrifying and phosphorus removal bacteria was only recirculated between the aerobic and anaerobic tanks. Therefore, the factors affected and restricted nitrification, denitrification and phosphorus removal in a traditional A/A/O process were resolved. This paper describes the optimum operation conditions for nitrogen and phosphorus removal using this system.

  16. The Optimum Harmonic Content for Discrete Fourier Series Representation of a Finite Discrete Data Set.

    Science.gov (United States)

    1986-06-01

    on revene of neconary and identify by block number) FIEL GRUP SB-GOUP Discrete data, modeling, Fourier Series, sampling, aliasing 19. ABSTRACT (Cornwu...on reverie if necessary and tcdentify by block number) it is well known that any real continuous-data function can be represented by a Fourier series...data function . For this case, there is an optimum truncation for its Fourier series representation. This fact has not been widely recognized. The

  17. Calculation of the optimum thickness of thermo-insulation for collectors of sunlight installations

    Directory of Open Access Journals (Sweden)

    Ermuratskii V.V.

    2005-12-01

    Full Text Available In the work the task of calculation of the optimum thickness of thermo-insulation for collectors of sunlight and accumulators of the heat is considered. The simplified model of calculation and the technique based on an estimation of efficiency of investment projects is offered. It is shown, that at calculation on the simplified model which are not taking into account financial streams, the overestimated values of thickness thermo-insulation turn out.

  18. Application of an optimum filter for a neptune 10 PC linac to reduce electron contamination

    Energy Technology Data Exchange (ETDEWEB)

    Bahreyni Toosi, M.T.; Saberi, H.; Hashemian, A. [Mashhad University of Medical Sciences, Medical Physics Dep., Faculty of Medicine, Mashhad (Iran, Islamic Republic of); Salek, R. [Mashhad University of Medical Sciences, Radiotherapy and Oncology Dep., Emam Reza Hospital, Mashhad (Iran, Islamic Republic of)

    2006-07-01

    Full text of publication follows: Skin sparing is one of the most desirable characteristics of high energy photon beams. However, photons emerging from the target of linacs are contaminated with secondary electrons as a result of their interactions with air, collimators, flattening filter and any other objects in their path. This phenomenon tends to increase patients skin dose. A practical way to reduce the contribution of electron contamination is to place a sheet of medium to high Z material just after the secondary collimators. Filters of different thicknesses and atomic numbers were applied. The dose reduction effect was evaluated by direct measurement using a pinpoint 0.015 cm{sup 3} PTW 31006 chamber in a Scanditronix water phantom. For this purpose, the percent depth dose was measured at various depths ranging from 0 to 210 mm. These measurements were carried out for three field sizes of 10 10, 20 20 and 25 25 cm{sup 2}. The setup was adjusted for SSD = 100 cm. The surface dose and D20/D10 were used as the criteria to determine the optimum filter. The complete geometry of the linac, filters and water phantom were also simulated by MCNP-4C code to compute the optimum filter. The results show a good agreement between the experimental and calculated data. A 0.4 mm thick lead foil produces the optimum condition. For open beams, the utilization of the optimum filter resulted in a 5.7, 7.9 and 9.6% reduction in PDD of 10 10, 20 20 and 25 25 cm{sup 2} respectively without any significant change in the quality of the x-ray beam. The flatness and homogeneity of the cross-line dose profile did not show significant changes at the 10 cm and the depth of maximum dose. (authors)

  19. Optimal Reinsurance Design for Pareto Optimum: From the Perspective of Multiple Reinsurers

    Directory of Open Access Journals (Sweden)

    Xing Rong

    2016-01-01

    Full Text Available This paper investigates optimal reinsurance strategies for an insurer which cedes the insured risk to multiple reinsurers. Assume that the insurer and every reinsurer apply the coherent risk measures. Then, we find out the necessary and sufficient conditions for the reinsurance market to achieve Pareto optimum; that is, every ceded-loss function and the retention function are in the form of “multiple layers reinsurance.”

  20. Optimum strain configurations for carrier injection in near infrared Ge lasers

    Science.gov (United States)

    Aldaghri, O.; Ikonić, Z.; Kelsall, R. W.

    2012-03-01

    The behavior of direct and indirect valleys in Ge, and the bandgap shrinking, under different tensile-strain conditions in bulk Ge and Ge quantum well structures are explored using the deformation potential and k .p methods. The doping density required for filling the indirect valleys up to the Γ-valley is calculated for various strain and growth conditions, as well as the efficiency of electron injection into the Γ-valley, and the optimum cases for Ge laser operation are identified.