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Mixture

Distribution by Scientific Domains
Chemistry45%
Life Sciences17%
Polymers and Materials Science13%
Medical Sciences9%
Engineering3%
Earth and Environmental Science3%
Physics and Astronomy2%
7 Other Domains8%
Distribution within Chemistry
Chemical Engineering11%
General & Introductory Chemistry8%
Mass Spectrometry6%
Analytical Chemistry4%
35 Other Subdomains52%

Kinds of Mixture

  • acetonitrile mixture
  • acid mixture
  • air mixture
  • amino acid mixture
  • anesthetic mixture
  • antioxidant mixture
  • artificial mixture
  • binary liquid mixture
  • binary mixture
  • binary solvent mixture
  • biological mixture
  • bromide mixture
  • cell mixture
  • chemical mixture
  • commercial mixture
  • complex biological mixture
  • complex mixture
  • complex peptide mixture
  • complex protein mixture
  • copolymer mixture
  • crude mixture
  • crude reaction mixture
  • crystal mixture
  • determinant mixture
  • diastereomeric mixture
  • different mixture
    		•
  • dna mixture
  • dye mixture
  • enzyme mixture
  • equal mixture
  • equilibrium mixture
  • equimolar mixture
  • ethanol mixture
  • eutectic mixture
  • feed mixture
  • finite mixture
  • flour mixture
  • fructose mixture
  • gas mixture
  • gaseous mixture
  • genotype mixture
  • heterogeneous mixture
  • homogeneous mixture
  • incubation mixture
  • initial mixture
  • inseparable mixture
  • isomer mixture
  • isomeric mixture
  • liquid crystal mixture
  • liquid mixture
  • methanol mixture
  • minor determinant mixture
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  • model mixture
  • monomer mixture
  • multicomponent mixture
  • multiphase mixture
  • nanoparticle mixture
  • natural mixture
  • oil mixture
  • organic solvent mixture
  • other mixture
  • oxide mixture
  • oxygen mixture
  • pcb mixture
  • peptide mixture
  • phase mixture
  • physical mixture
  • plant mixture
  • pollen mixture
  • polymer mixture
  • polymerization mixture
  • powder mixture
  • product mixture
  • protein mixture
  • racemic mixture
  • reaction mixture
  • refrigerant mixture
  • resin mixture
    		•
  • salt mixture
  • same mixture
  • seed mixture
  • simple mixture
  • solid mixture
  • solution mixture
  • solvent mixture
  • species mixture
  • standard mixture
  • starting mixture
  • stoichiometric mixture
  • sugar mixture
  • surfactant mixture
  • synthesis mixture
  • synthetic mixture
  • ternary mixture
  • test mixture
  • toluene mixture
  • unique mixture
  • various mixture
  • water mixture
  • water solvent mixture

    • Terms modified by Mixture

  • mixture analysis
  • mixture component
  • mixture composition
  • mixture consisting
  • mixture containing
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  • mixture design
  • mixture distribution
  • mixture model
  • mixture modeling
  • mixture models
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  • mixture ratio
  • mixture representation
  • mixture solution
  • mixture solvent
  • mixture synthesis
    		•
  • mixture used

    • Selected Abstracts

    PRIMUS: a Windows PC-based system for small-angle scattering data analysis

    JOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 5 2003
    Petr V. Konarev
    A program suite for one-dimensional small-angle scattering data processing running on IBM-compatible PCs under Windows 9x/NT/2000/XP is presented. The main program, PRIMUS, has a menu-driven graphical user interface calling computational modules to perform data manipulation and analysis. Experimental data in binary OTOKO format can be reduced by calling the program SAPOKO, which includes statistical analysis of time frames, averaging and scaling. Tools to generate the angular axis and detector response files from diffraction patterns of calibration samples, as well as binary to ASCII transformation programs, are available. Several types of ASCII files can be directly imported into PRIMUS, in particular, sasCIF or ILL-type files are read without modification. PRIMUS provides basic data manipulation functions (averaging, background subtraction, merging of data measured in different angular ranges, extrapolation to zero sample concentration, etc.) and computes invariants from Guinier and Porod plots. Several external modules coupled with PRIMUSvia pop-up menus enable the user to evaluate the characteristic functions by indirect Fourier transformation, to perform peak analysis for partially ordered systems and to find shape approximations in terms of three-parametric geometrical bodies. For the analysis of mixtures, PRIMUS enables model-independent singular value decomposition or linear fitting if the scattering from the components is known. An interface is also provided to the general non-linear fitting program MIXTURE, which is designed for quantitative analysis of multicomponent systems represented by simple geometrical bodies, taking shape and size polydispersity as well as interparticle interference effects into account. [source]

    APPLICATION OF COEFFICIENT OF FRICTION TO THE SEPARATION OF COCOA HUSK,BEANS MIXTURE

    JOURNAL OF FOOD PROCESS ENGINEERING, Issue 5 2007
    O.K. OWOLARAFE
    ABSTRACT Investigation was carried out on the application of coefficient of friction in the separation of cocoa beans,husk mixture. An inclined plane at angles 20, 25 and 35°rotating at different speeds (215, 250 and 260 rpm) and receiving the mixture at heights 30, 60 and 90 mm, was used for the study. The result indicates that within the range of factors considered, the separation efficiency of the beans from the mixture increases with increase in speed of rotation and height of fall, while it decreases with increase in angle of inclination. Statistical analysis shows that the effects of each of the factors and that of their interaction are significant at 99%. The best separation efficiency (99%) was observed at a speed of 250 rpm, an angle of inclination of 25° and a height fall of 90 mm. PRACTICAL APPLICATIONS Separation of cocoa beans from the husks has been a serious problem in cocoa processing. Handpicking is still being used to separate the mixture of cocoa beans,husk even with the mechanical pod breaker available. This therefore constitutes a tedious operation. An inclined plane mechanism tested for the separation of the mixture in this study can be incorporated into the design of the cocoa pod processor to reduce the drudgery involved in cocoa processing and improve the quality of the product. [source]

    QUALITIES OF EXTRUDED PUFFED SNACKS FROM MAIZE/SOYBEAN MIXTURE

    JOURNAL OF FOOD PROCESS ENGINEERING, Issue 2 2006
    A. OBATOLU VERONICA
    ABSTRACT A maize-based snack was fortified with partially defatted soybean (PDS) at 10, 20 and 30% of total weight and analyzed for physical (expansion ratio, density, color and texture [brittleness, breaking strength and hardness]), chemical and sensory characteristics. Incorporating PDS in a maize-based snack had a positive effect on chemical properties but had a negative effect on the physical and sensory characteristics. The results showed a protein range of 9.3 ± 0.90% in 100% maize-based snacks to 19.3 ± 1.03% in 30% replacements with soybean. The overall consumer acceptability test showed a score range between 4.1 ± 0.82 in 30% level of fortification and 8.2 ± 1.04 in 100% maize and 10% fortified extrudate. Panelists perceived the puffed extrudates with 20 and 30% PDS as not puffy or crispy, less acceptable and harder to crack. Up to 20% of PDS could be used in maize-based puffed extrudates. [source]

    ELECTRICAL CONDUCTIVITY OF HEATED CORNSTARCH,WATER MIXTURES

    JOURNAL OF FOOD PROCESS ENGINEERING, Issue 6 2009
    EDUARDO MORALES-SANCHEZ
    ABSTRACT Electrical conductivity (EC) of cornstarch,water mixtures in the range 10:90 to 70:30 (w/w) was studied as a function of temperature. An external resistive heating system equipped with an electronic device capable of monitoring EC in real time was used and EC of the mixtures was measured while heated at a rate of 5C/min. Results showed that EC went through four different temperature-dependent stages (A, B, C and D). Stage B (41C to 64C) showed a lower EC increasing rate when compared with that of Stage A (from 25C to 41C), probably as a result of starch granule swelling. In Stage C (64C to 78C), EC behavior was found to be dependent on water content. When water content was more than 50%, the value for EC increased. On the other side, EC decreased when water content was less than 50%. Stage C was related to starch gelatinization, according to differential scanning calorimetry results obtained in this study. In Stage D (78C to 92C), a steady increase in EC was observed, probably as a result of the total solubilization of starch in water. It was concluded that Stage C in EC graphs corresponded to cornstarch gelatinization, so it might be possible to use EC monitoring as an alternative technique to measure cornstarch thermal characteristics with different contents of water. PRACTICAL APPLICATIONS Electrical conductivity can be used as an adequate technique to monitor gelatinization, granule swelling and phase change of starch as a function of temperature in corn starch,water mixtures with a wide range of water contents. With this technique, it is also possible to calculate important thermal parameters, such as the beginning and end of the gelatinization and the energy activation for the heating process of cornstarch. This can lead to a better design and control of important industrial corn processes such as alkaline cooking. [source]

    FLOW PROPERTIES OF MALT CONCENTRATE-SWEETENED CONDENSED MILK MIXTURES

    JOURNAL OF FOOD PROCESS ENGINEERING, Issue 3 2000
    S. TEJINDER
    ABSTRACT The rheological characteristics of various malt extract concentrate-sweetened condensed milk mixtures in the ratios of 50:50, 60:40, 70:30 and 80:20 (w/w) were studied at 30 to 80C, using a coaxial viscometer. The magnitudes of flow behavior index varied from 0.42,0.93. Experimental temperatures and concentrations of sweetened condensed milk considerably affected pseudoplasticity, consistency index and yield stress values of the mixtures. At 60 to 80C, the 60:40, 70:30 and 80:20 mixtures showed spectacularly higher flow behavior index values than those of the 50:50. The yield stress values increased with increasing temperature. The increases were considerably high in the 50:50 mixtures. The hulless barley malt concentrate-sweetened condensed milk mixtures, however, were mildly non-Newtonian and showed decreases in the values for yield stress with increasing temperatures. The activation energy values for flow behavior index and yield stress were negative in magnitudes, whereas those of consistency index were positive, which ranged from 1.6 to 15.0 Kcal/g mole. [source]

    EFFECTS OF PROCESS VARIABLE CONDITIONS ON MINERAL AND CHEMICAL COMPOSITION OF EXTRUDED AFRICAN BREADFRUIT (TRECULIA AFRICANA DECNE) MIXTURES

    JOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 4 2009
    TITUS U. NWABUEZE
    ABSTRACT Five levels of African breadfruit (Treculia africana), corn and soybean mixtures (fc) in ratios of 40:5:55, 55:5:40, 70:5:25, 85:5:10 and 100:0:0, respectively, were hydrated to 15, 18, 21, 24 and 27% (fm) and extruded at 100, 120, 140, 160 and 180 rpm (ss) in a Brabender single-screw extruder. The objective was to study effects of process variable conditions on mineral and chemical composition of the mixtures. Models developed by response surface analysis were high (R2 = 0.7646,0.9732) for Na, Ca, Mg, protein, fat, fiber and carbohydrate, and showed no significant (P > 0.05) lack of fit. All process variables had significant (P , 0.05) linear effects on Mg, protein and carbohydrate, quadratic effects on fat, energy and Mg and cross-product effects on Ca, Mg, protein and carbohydrate, when fc interacted with either fm or ss. Optimum process variable conditions that gave the best mineral and chemical composition were obtained at 40:5:55(fc), 18% (fm) and 140 rpm (ss). PRACTICAL APPLICATIONS The potentials of African breadfruit as a nutrient resource and its position in the food cycle of the people in the subtropical African countries makes its blending with other local ingredients one important way of expanding the scope of its utilization. African breadfruit seeds provide a delicacy and a specialized meal when consumed alone or with shelled milk-corn. The versatility and acceptance of extrusion as a processing technology and its benefits over conventional methods and worldwide adaptability to a variety of crops, makes its application in this research appropriate. Optimization of process variable conditions affecting mineral and chemical composition of extruded and unextruded mixtures of African breadfruit, corn and soybean, using response surface analysis, was the thrust of the study. It is expected to produce an optimum process combination that could give the best mineral and chemical composition for a possible scale-up operation in African breadfruit seed processing enterprises. [source]

    MIXTURES OF BEEF TRIPE, BEEF LIVER AND SOYBEANS APPLIED TO FOOD DEVELOPMENT

    JOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 3 2007
    L. MALVESTITI
    ABSTRACT A nutritive sausage-type product was developed with beef tripe, beef liver and soybeans as ingredients. A three-component mixture design was used to obtain seven different formulations (minimum of each main ingredient: 16.5%, maximum: 67.0%). Ingredients were ground, mixed and packed tightly with a polypropylene film to obtain a roll. Pieces were cooked in boiling water for 90 min. The composition of the obtained products varied within the following ranges: proteins 17.32,25.56 g/100 g, lipids 3.22,3.87 g/100 g, crude fiber 1.50,4.50 g/100 g, minerals 1.44,2.72 g/100 g. Total iron levels varied between 1.39 and 2.98 mg/100 g and calcium levels between 15.07 and 34.01 mg/100 g. Surface response analysis was applied to parameters obtained from texture profile analysis (hardness, adhesiveness, cohesiveness and elasticity). Products hardness increased when the soy content increased; on the contrary, formulations enriched in beef tripe were those of higher elasticity and cohesiveness. Color was mainly determined by the incorporation of liver. A nontrained panel was used to evaluate the acceptance of the different formulations. The most accepted one was that with equal proportions of the three main ingredients. Microbiological challenge testing showed that the thermal treatment was enough for assuring the product safeness even in samples with high initial microbial charge. [source]

    EFFECT of EXTRUSION ON TRYPSIN INHIBITOR CONTENTS of SOY-SWEET POTATO MIXTURES

    JOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 6 2000
    M.O. IWE
    Mixtures of soy and sweet potato (Ipomoea batatas) (L.) Lam), flours containing 18%, 25% and 30% moisture, respectively, were extruded in a single screw extruder. Results showed that inactivation of trypsin inhibitor was enhanced by both reductions in feed moisture and soy flour contents of sample mixtures. Hence subsequent extrusion was carried at 18% feed moisture with variable feed ratio, screw rotation speed and die diameter, using a central composite rotatable, near orthogonal experimental design. Results further showed that the effect of increasing the ratio of soy in the mixture was linearly significant (p > 0.05). Optimum Trypsin Inhibitor (TI) inactivation value of 3.40 mg/g was predicted at a feed composition of 80% sweet potato, 9 mm die diameter and 154 rpm, respectively. [source]

    CHEMICAL PROPERTIES of PROCESSED RAS CHEESE SPREADS AS AFFECTED BY EMULSIFYING SALT MIXTURES,

    JOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 3 2000
    LAILA B. ABDEL-HAMID
    Processed cheese spreads were produced using Ras cheese and various emulsifying salt mixtures. Acidified Ras cheese (2 month old) was used as the cheese base with salt mixtures (1) Na-pyrophosphate + Na-polyphosphate, (2) Na-pyrophosphate + Na-polyphosphate + Na-tripolyphosphate, and (3) Na-pyrophosphate + Na-polyphosphate + Na-orthophosphate + Na-tripolyphosphate. For comparison, cheese spreads were also made with commercial emulsifying salts JOHA S10, S9 special, and NO. Total and soluble nitrogen (SN), peptization, ash, mineral, pH value, and potentiometric acid-base titration for the processed cheese were studied. Ash, sodium and potassium contents showed a significant difference among the treatments. the pH values tended to decrease with increasing polyphosphate ratio in the salt mixture and with prolonging the storage period. the SN increased with increasing the pyrophosphate percent in the salt mixture and with higher pH value. the buffering capacity of cheese made of salt mixtures difsered from those made of the commercial mixtures, and it was correlated to the individual salts used in the mixture. The mixtures of (1) 70+30%, (2) 60+30+10% and (3) 50+20+20+10% can be recommended for producing the spreadable processed Ras cheese with acceptable chemical properties. [source]

    GUSTATORY REACTION TIME AND TIME INTENSITY MEASUREMENTS OF TREHALOSE AND SUCROSE SOLUTIONS AND THEIR MIXTURES

    JOURNAL OF SENSORY STUDIES, Issue 2 2009
    MARA VIRGINIA GALMARINI
    ABSTRACT Dynamic sweetness perception of commercial food grade trehalose, sucrose solutions and their mixtures were studied for a wide range of concentrations. For gustatory reaction time (GRT), concentrations ranged from 2.3 to 13.8% for sucrose and up to 23.0% for trehalose. For time intensity (T-I) sucrose or trehalose solutions (concentration range 2.3,36.8%) and their combinations (23.0 and 36.8% total solids) were analyzed. Trehalose had bigger GRT along the studied range. Both sugars presented similar values for persistence and times of plateau and to maximum intensity, while a significant difference was observed in intensity and GRT at equal concentrations. Trehalose had longer persistence than sucrose in equi -sweet solutions. Overall sweetness profile of some sucrose solutions (i.e., 29.9% sucrose solution and 0.6 sucrose/trehalose ratio mixture at 36.8% total solids) were perceived as similar to mixtures of sucrose/trehalose or single trehalose solutions, which suggests the possibility of sugar replacement without completely modifying sweetness perception. PRACTICAL APPLICATIONS It has been suggested that trehalose may be a potential substitute for sucrose and other sugars used in food formulation because, although its chemical structure is very similar to that of sucrose, it is more stable at low pH and high temperatures. It is not involved in caramelization and does not participate in Maillard reaction with amino acids/proteins. In order to fully establish the potential of trehalose as a functional replacement of sucrose we have determined the sweetness dynamic profile (gustatory reaction time and time-intensity curves) of trehalose solutions and sucrose/trehalose solutions; this aspect is needed for adequately replacing (partially or totally) sucrose in food systems. [source]

    EVALUATION OF THE CHARACTER IMPACT ODORANTS IN SKIM MILK POWDER BY SENSORY STUDIES ON MODEL MIXTURES

    JOURNAL OF SENSORY STUDIES, Issue 1 2004
    Y. KARAGÜL-YÜCEER
    ABSTRACT The objective of this study was to verify key aroma-active compounds responsible for reconstituted fresh skim milk powder (SMP) aroma using threshold analysis, odor activity values, and model systems. Twelve odor-active compounds of SMP and one odor-active compound from fluid milk were selected based on flavor dilution factors from gas chromatography-olfactometry. Thresholds for the 13 odor-active compounds were identified using five-set ascending forced choice threshold analysis in odor-free water and fluid skim milk. Model systems were prepared using rehydrated milk retentate (RMR). The aroma of each model was evaluated by descriptive sensory analysis and by difference-from-control testing using a trained panel. The aroma of reconstituted fresh SMP and liquid skim milk were used as controls. Models containing a mixture of twelve of the thirteen chemicals had the most similar odor characteristics to rehydrated SMP aroma (9.0/10) indicating that these compounds constitute the character impact odorants of rehydrated fresh SMP. [source]

    PHYSICAL, SENSORY AND FLOW PROPERTIES OF WHEAT STARCH,DAIRY BY-PRODUCT SPRAY-DRIED PEKMEZ MIXTURES

    JOURNAL OF TEXTURE STUDIES, Issue 2 2008
    DURMU
    ABSTRACT Pekmez, also known as a concentrated grape juice, was spray dried in a laboratory-type pilot drying unit to obtain pekmez powder (PP). The flow characteristics of PP, wheat starch (WS) and some dairy by-products (whey powder, skim milk powder, calcium caseinate and sodium caseinate) systems as binary and ternary mixtures were studied. The empirical power law model fitted the apparent viscosity,rotational speed data. PP,dairy by-product and WS,dairy by-product mixed solutions exhibited a shear-thinning behavior at 21C with flow behavior index (n) values of 0.86 , n , 0.92 and 0.06 , n , 0.27, respectively. WS,dairy by-product mixed solutions showed high shear-thinning behavior with the highest consistency index (k = 25,425,180,599 mPa·sn). However, PP,WS and PP,WS,dairy by-product mixed solutions at the same temperature exhibited the shear-thickening behavior with flow behavior index (n) values of 1.05 , n , 1.18. PRACTICAL APPLICATIONS Pekmez has become popular as a healthy food product; therefore, its rheologic properties were extensively studied by some researchers. However, pekmez powder (PP) is a new product and has not been produced yet in the food industry. Spray drying of foods has been spread recently in almost all food industry branches because it provides some advantages such as extending the shelf life, storage stability, decreasing the storage costs of the food products, etc. For this reason, production technology is first developed; PP is produced and studied in this study. There is no published data informing the rheologic, physical and sensory properties of pekmez or PP as binary and ternary mixtures with other components such as wheat starch (WS) and any dairy by-product. The purpose of this study was mainly to characterize the rheologic behavior of the PP,WS,dairy by-product mixed solutions and determine their physical and sensory properties. [source]

    ESTIMATING COMPONENTS IN FINITE MIXTURES AND HIDDEN MARKOV MODELS

    AUSTRALIAN & NEW ZEALAND JOURNAL OF STATISTICS, Issue 3 2005
    D.S. Poskitt
    Summary When the unobservable Markov chain in a hidden Markov model is stationary the marginal distribution of the observations is a finite mixture with the number of terms equal to the number of the states of the Markov chain. This suggests the number of states of the unobservable Markov chain can be estimated by determining the number of mixture components in the marginal distribution. This paper presents new methods for estimating the number of states in a hidden Markov model, and coincidentally the unknown number of components in a finite mixture, based on penalized quasi-likelihood and generalized quasi-likelihood ratio methods constructed from the marginal distribution. The procedures advocated are simple to calculate, and results obtained in empirical applications indicate that they are as effective as current available methods based on the full likelihood. Under fairly general regularity conditions, the methods proposed generate strongly consistent estimates of the unknown number of states or components. [source]

    Effect of gold nanoparticle on the microscopic morphology of white blood cell

    CYTOPATHOLOGY, Issue 2 2009
    V. Wiwanitkit
    Background:, In medicine, there is limited knowledge on the toxicity of nanoparticles. In medicine, there has been limited knowledge on the effect of nanoparticles on the white blood cell. Objective:, To evaluate the effect of gold nanoparticle on the microscopic morphology of white blood cell. Setting:, Chulalongkorn Univesity, Bangkok, Thailand. Method:, This study was performed as an experimental study. Mixture of gold nanoparticle solution and blood sample was prepared and analysed. Result:, This work revealed that after mixing the blood sample with gold nanoparticle solution, accumulation of gold nanoparticle in the white blood cell was observed. Conclusion:, The effect of gold nanoparticle on the white blood cell can be detected and this knowledge can be used in cytotoxic drug treatment. [source]

    Direct and Rapid Detection of Diphtherotoxin via Potentiometric Immunosensor Based on Nanoparticles Mixture and Polyvinyl Butyral as Matrixes

    ELECTROANALYSIS, Issue 24 2005
    Dianping Tang
    Abstract In this paper a novel potentiometric immunosensor for direct and rapid detection of diphtherotoxin (D-Ag) has been developed by means of self-assembly of monoclonal diphtheria antibody (D-Ab) onto a platinum electrode based on nanoparticles mixture (containing gold nanoparticles and silica nanoparticles) and polyvinyl butyral (PVB) as matrixes. At first, D-Ab was absorbed onto the surface of nanoparticles mixture, and then they were entrapped into polyvinyl butyral sol-gel network on a platinum electrode. The detection is based on the change in the potentiometric response before and after the antigen-antibody reaction in a phosphate buffer solution (pH,7.0). The immobilized D-Ab exhibited direct potentiometric response toward D-Ag. In comparison to the conventional applied methods, this strategy could allow antibodies immobilized with higher loading amount and better retained immunoactivity, as demonstrated by potentiometric response, cyclic voltammetry and electrochemical impedance spectroscopy of the immunosensor. The immunosensor with nanoparticles mixture exhibited much higher sensitivity, better reproducibility, and long-term stability than that with gold nanoparticles or silica nanoparticles alone. The linear range was from 5.0×10,3 to 1.2,,g,mL,1 with a detection limit of 1.1×10,3,,g,mL,1. Up to 16 successive assay cycles with retentive sensitivity were achieved for the probes regenerated with in 0.2,mol,L,1 glycine-hydrochloric acid (Gly-HCl) buffer solution and 0.25,mol,L,1 NaCl. Moreover, the immunosensor with nanoparticles mixture was applied to evaluate a number of practical specimens with potentiometric results in acceptable agreement with those given by the ELISA method, implying a promising alternative approach for detecting diphtherotoxin in the clinical diagnosis. [source]

    Universal multiplex PCR and CE for quantification of SMN1/SMN2 genes in spinal muscular atrophy

    ELECTROPHORESIS, Issue 7 2009
    Chun-Chi Wang
    Abstract We established a universal multiplex PCR and CE to calculate the copy number of survival motor neuron (SMN1 and SMN2) genes for clinical screening of spinal muscular atrophy (SMA). In this study, one universal fluorescent primer was designed and applied for multiplex PCR of SMN1, SMN2 and two internal standards (CYBB and KRIT1). These amplicons were separated by conformation sensitive CE. Mixture of hydroxyethyl cellulose and hydroxypropyl cellulose were used in this CE system. Our method provided the potential to separate two 390-bp PCR products that differ in a single nucleotide. Differentiation and quantification of SMN1 and SMN2 are essential for clinical screening of SMA patients and carriers. The DNA samples included 22 SMA patients, 45 parents of SMA patients (obligatory carriers) and 217 controls. For evaluating accuracy, those 284 samples were blind-analyzed by this method and denaturing high pressure liquid chromatography (DHPLC). Eight of the total samples showed different results. Among them, two samples were diagnosed as having only SMN2 gene by DHPLC, however, they contained both SMN1 and SMN2 by our method. They were further confirmed by DNA sequencing. Our method showed good agreement with the DNA sequencing. The multiplex ligation-dependent probe amplification (MLPA) was used for confirming the other five samples, and showed the same results with our CE method. For only one sample, our CE showed different results with MLPA and DNA sequencing. One out of 284 samples (0.35%) belonged to mismatching. Our method provided a better accurate method and convenient method for clinical genotyping of SMA disease. [source]

    Mixture and single-substance toxicity of selective serotonin reuptake inhibitors toward algae and crustaceans

    ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 1 2007
    Anne Munch Christensen
    Abstract Selective serotonin reuptake inhibitors (SSRIs) are used as antidepressant medications, primarily in the treatment of clinical depression. They are among the pharmaceuticals most often prescribed in the industrialized countries. Selective serotonin reuptake inhibitors are compounds with an identical mechanism of action in mammals (inhibit reuptake of serotonin), and they have been found in different aqueous as well as biological samples collected in the environment. In the present study, we tested the toxicities of five SSRIs (citalopram, fluoxetine, fluvoxamine, paroxetine, and sertraline) as single substances and of citalopram, fluoxetine, and sertraline in binary mixtures in two standardized bioassays. Test organisms were the freshwater algae Pseudokirchneriella subcapitata and the freshwater crustacean Daphnia magna. In algae, test median effect concentrations (EC50s) ranged from 0.027 to 1.6 mg/L, and in daphnids, test EC50s ranged from 0.92 to 20 mg/L, with sertraline being one of the most toxic compounds. The test design and statistical analysis of results from mixture tests were based on isobole analysis. It was demonstrated that the mixture toxicity of the SSRIs in the two bioassays is predictable by the model of concentration addition. Therefore, in risk assessment based on chemical analysis of environmental samples, it is important to include the effect of all SSRIs that are present at low concentrations, and the model of concentration addition may be used to predict the combined effect of the mixture of SSRIs. [source]

    A TRLFS Study on the Complexation of CmIII and EuIII with 2,6-Bis(5,6-dipropyl-1,2,4-triazin-3-yl)pyridine in Water/Methanol Mixture

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 19 2010
    Sascha Trumm
    Abstract The complexation of CmIII and EuIII with 2,6-bis(5,6-dipropyl-1,2,4-triazin-3-yl)pyridine (nPr-BTP) in water/methanol solution is studied. 1:3 complexes [M(nPr-BTP)3]3+ form from the solvated metal ions upon addition of ligand. The conditional stability constants are log,K = 14.4 and log,K = 11.9. For both metal ions the complexation reaction is both enthalpy and entropy driven. ,H is 10.1 kJ/mol more negative than ,H, whereas the entropy difference is small. The difference in ,G between the formation of the CmIII and EuIII complexes is in good agreement with nPr-BTP's selectivity in liquid-liquid extraction. [source]

    Minerals as Model Compounds for Cu/ZnO Catalyst Precursors: Structural and Thermal Properties and IR Spectra of Mineral and Synthetic (Zincian) Malachite, Rosasite and Aurichalcite and a Catalyst Precursor Mixture

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 10 2009
    Malte Behrens
    Abstract The Cu/ZnO system is a model for Cu/ZnO/Al2O3 catalysts, which are employed industrially for the synthesis of methanol. These catalysts are usually prepared from mixed basic carbonate precursors. A complex phase mixture, with constituents structurally related to the minerals rosasite andaurichalcite, is present at the industrially applied composition (Cu/Zn , 70:30). Using minerals and phase-pure synthetic samples as references, a comprehensive characterisation of such a phase mixture, including the determination of the individual compositions of the different phases, has been attempted by complementary analytical laboratory techniques (XRD, TGA, IR). The results are critically discussed in light of the complexity of the system. A thermally very stable carbonate species , well-known for mixed synthetic systems , is also detected for the mineral reference samples. Significant amounts of amorphous phases are found to be present in the synthetic zincian malachite sample but not in synthetic aurichalcite or the catalyst precursor. A simplified explanation for the shift of the characteristic 20 reflection of the malachite structure as a function of Zn incorporation based on the varying average Jahn,Teller distortion of the MO6 octahedra is proposed. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source]

    Syntheses, Spectroscopic Studies, and Crystal Structures of Chiral [Rh(aminocarboxylato)(,4 -cod)] and Chiral [Rh(amino alcohol)(,4 -cod)](acetate) Complexes with an Example of a Spontaneous Resolution of a Racemic Mixture into Homochiral Helix-Enantiomers

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 11 2006
    Mohammed Enamullah
    Abstract The dimeric complex acetato(,4 -cycloocta-1,5-diene)rhodium(I), [Rh(O2CMe)(,4 -cod)]2 (cod = cycloocta-1,5-diene), reacts with amino acids [HAA = L -alanine, (S)-2-amino-2-phenylacetic acid (L -phenylglycine), N -methylglycine, and N -phenylglycine] and with the amino alcohol (S)-2-amino-2-phenylethanol to afford the aminocarboxylato(,4 -cycloocta-1,5-diene)rhodium(I) complexes [Rh(AA)(,4 -cod)] (AA = deprotonated amino acid = aminocarboxylato ligand) and [(S)-2-amino-2-phenylethanol](,4 -cycloocta-1,5-diene)rhodium(I) acetate, [Rh{(S)-HOCH2,CH(Ph)-NH2}(,4 -cod)](O2CMe) (V). The complexes are characterized by IR, UV/Vis, 1H/13C NMR and mass spectroscopy. The achiral N -phenylglycine ligand gives a chiral N -phenylglycinato complex [Rh(O2C,CH2,NHPh)(,4 -cod)] (IV) with the amine nitrogen atom becoming the stereogenic center upon metal coordination. Complex IV crystallizes in the tetragonal, chiral space group P43 and the crystal structure reveals twofold spontaneous resolution of a racemic mixture into homochiral helix-enantiomers. The investigated crystal contained only one type of helix, namely (left-handed or M- ) 43 -helical chains. This is traced first to an intermolecular N,H···O hydrogen bonding from the stereogenic amino group to a neighboring unligated carboxyl oxygen atom that connects only molecules of the same (R)-configuration into (left-handed or M- ) 43 -helical chains. This intrachain homochirality is supplemented, secondly, by the interlocking of adjacent chains with their corrugated van der Waals surface to allow for an interchain transmission of the sense of helicity, building the single crystal from the same homochiral helix-enantiomer. The enantiomeric amino alcohol complex V crystallizes in the monoclinic, noncentrosymmetric (Sohncke) space group P21. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source]

    Tunable Memory Characteristics of Nanostructured, Nonvolatile Charge Trap Memory Devices Based on a Binary Mixture of Metal Nanoparticles as a Charge Trapping Layer,

    ADVANCED MATERIALS, Issue 2 2009
    Jang-Sik Lee
    Tunable memory characteristics are investigated according to the metal-nanoparticle species being used in memory devices. The memory devices are fabricated using diblock copolymer micelles as templates to synthesize nanoparticles of cobalt, gold, and a binary mixture thereof. Programmable memory characteristics show different charging/discharging behaviors according to the storage element configurations as confirmed by nanoscale device characterization. [source]

    Mixture-based adaptive probabilistic control

    INTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING, Issue 2 2003
    Miroslav Kárnı
    Abstract Quasi-Bayes algorithm, combined with stabilized forgetting, provides a tool for efficient recursive estimation of dynamic probabilistic mixture models. They can be interpreted either as models of closed-loop with switching modes and controllers or as a universal approximation of a wide class of non-linear control loops. Fully probabilistic control design extended to mixture models makes basis of a powerful class of adaptive controllers based on the receding-horizon certainty equivalence strategy. Paper summarizes the basic elements mentioned above, classifies possible types of control problems and provides solution of the key one referred to as ,simultaneous' design. Results are illustrated on mixtures with components formed by normal auto-regression models with external variable (ARX). Copyright © 2003 John Wiley & Sons, Ltd. [source]

    4-Aryl-2-quinolones through a Pseudo-Domino Heck/Buchwald,Hartwig Reaction in a Molten Tetrabutylammonium Acetate/ Tetrabutylammonium Bromide Mixture

    ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 3 2007
    Gianfranco Battistuzzi
    Abstract 4-Aryl-2-quinolones can be prepared from readily available o -bromocinnamamide and aryl iodides using phosphine-free palladium(II) acetate as the precatalyst and a molten tetra(n -butyl)ammonium acetate/tetra(n -butyl)ammonium bromide mixture as the reaction medium. The reaction proceeds through a pseudo-domino process involving two mechanistically independent, sequential catalytic cycles: a Heck reaction followed by an intramolecular Buchwald,Hartwig CN bond forming reaction. [source]

    Oxidative Stability of Soybean and Sesame Oil Mixture during Frying of Flour Dough

    JOURNAL OF FOOD SCIENCE, Issue 7 2004
    J. Chung
    ABSTRACT: Effects of roasted sesame seed oil on the oxidative stability of soybean oil during frying of flour dough at 160 °C were studied by determining fatty acid composition and conjugated dienoic acid (CDA), p -anisidine (PA), and free fatty acid (FFA) values. Concentration of sesame oil in frying oil was 0%, 10%, 20%, or 30% (v/v). Tocopherols and lignan compounds in the frying oil were also determined by high-performance liquid chromatography. As the number of fryings performed by the oil increased, linolenic acid content in frying oil decreased, and the decreasing rate was lower in frying oil containing sesame oil than in the oil containing no sesame oil. CDA and FFA values of frying oil increased during frying and their relative values to the initial value were lower in frying oil containing sesame oil than in the oil containing no sesame oil. This indicates that the addition of sesame oil improved thermooxidative stability of frying oil, possibly due to the presence of lignan compounds in sesame oil. Tocopherols and lignan compounds in frying oil decreased during frying. As the amount of sesame oil in frying oil increased, degradation of tocopherols increased and lignan compounds degradation decreased. Tocopherols were suggested to protect lignan compounds in sesame oil from decomposition during frying. [source]

    Synthesis of Phase-Pure Pb(ZnxMg1,x)1/3Nb2/3O3 up to x= 0.7 from a Single Mixture via a Soft-Mechanochemical Route

    JOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 12 2000
    Seiji Shinohara
    Phase-pure perovskite Pb(ZnxMg1,x)1/3Nb2/3O3 solid solution (PZxM1,xN) is obtained for x, 0.7 by heating a milled stoichiometric mixture of PbO, Mg(OH)2, Nb2O5, and 2ZnCO3·3Zn(OH)2·H2O at 1100°C for 1 h. Percent perovskite (fP) with respect to total crystalline phase decreases with increasing temperature of subsequent heating then increases to 900°C for the mixtures where x, 0.8 and milled for 3 h. For mixtures with x= 0.9 and x= 1, fP decreases monotonically. Curie temperature increases almost linearly with increasing x up to x= 0.7. The maximum dielectric constant at 1 kHz is 2×104 and 1.7×104 for the mixture with x= 0.4 and x= 0.7, respectively. The stabilization mechanism of strained perovskite is discussed. [source]

    Open-Label Exploration of an Intravenous Nalbuphine and Naloxone Mixture as an Analgesic Agent Following Gynecologic Surgery

    PAIN MEDICINE, Issue 6 2007
    Assaf T. Gordon MD
    ABSTRACT Objective., The purpose of this series was to explore a 12.5:1 fixed-dose ratio of an intravenous nalbuphine and naloxone mixture (NNM) for use in patients following gynecologic surgery. Design and Patients., Open-label, nonrandomized case series. The first series was a dose-ranging investigation for 12 patients following elective total abdominal hysterectomy or myomectomy. In this series, fentanyl was used for intraoperative analgesia, and patients were assigned to a lower NNM (2.5 mg/0.2 mg) or to a higher NNM (5 mg/0.4 mg) dose group. The second series evaluated the fixed dose of 5 mg nalbuphine/0.4 mg naloxone for four patients undergoing ambulatory gynecologic procedures. In the second series, no opioid agents were administered intraoperatively to eliminate the possibility of mu-opioid reversal by naloxone postoperatively. Outcome Measures., Pain control was assessed using a Verbal Pain Scale (0,10). Vital signs, side effects, and adverse events were recorded to determine drug safety. Results., In the first series, there were no adverse events; however, each patient required rescue medication (either morphine or fentanyl). In the second series, two of the four patients reported a reduction in pain following drug administration and did not require any further analgesic agents in the 3-hour postoperative period. One patient had an asymptomatic lowering of heart rate after receiving the drug. Conclusion., Additional research of the unique combination therapy of nalbuphine and naloxone is warranted to further determine its potential clinical efficacy and safety. [source]

    Mixture and mixture,process variable experiments for pharmaceutical applications

    PHARMACEUTICAL STATISTICS: THE JOURNAL OF APPLIED STATISTICS IN THE PHARMACEUTICAL INDUSTRY, Issue 4 2004
    Christine M. Anderson-Cook
    Abstract Many experiments in research and development in the pharmaceutical industry involve mixture components. These are experiments in which the experimental factors are the ingredients of a mixture and the response variable is a function of the relative proportion of each ingredient, not its absolute amount. Thus the mixture ingredients cannot be varied independently. A common variation of the mixture experiment occurs when there are also one or more process factors that can be varied independently of each other and of the mixture components, leading to a mixture,process variable experiment. We discuss the design and analysis of these types of experiments, using tablet formulation as an example. Our objective is to encourage greater utilization of these techniques in pharmaceutical research and development. Copyright © 2004 John Wiley & Sons Ltd. [source]

    Vibrational Spectroscopic Studies on the Disulfide Formation and Secondary Conformational Changes of Captopril,HSA Mixture after UV-B Irradiation

    PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 6 2005
    Mei-Jane Li
    ABSTRACT The effects of pH and ultraviolet-B (UV-B) irradiation on the secondary structure of human serum albumin (HSA) in the absence or presence of captopril were investigated by an attenuated total reflection (ATR)/Fourier transform infrared (FTIR) spectroscopy. The UV-B exposure affecting the stability of captopril before and after captopril,HSA interaction was also examined by using confocal Raman microspectroscopy. The results indicate that the transparent pale-yellow solution for captopril,HSA mixture in all pH buffer solutions, except pH 5.0,7.0, changed into a viscous form then a gel form with UV-B exposure time. The secondary structural transformation of HSA in the captopril,HSA mixture with or without UV-B irradiation was found to shift the maxima amide I peak in IR spectra from 1652 cm,1 assigned to ,-helix structure to 1622 cm,1 because of a ,-sheet structure, which was more evident in pH 3.0, 8.0 or 9.0 buffer solutions. The Raman shift from 1653 cm,1 (,-helix) to 1670 cm,1 (,-sheet) also confirmed this result. Captopril dissolved in distilled water with or without UV-B irradiation was determined to form a captopril disulfide observed from the Raman spectra of 512 cm,1, which was exacerbated by UV-B irradiation. There was little disulfide formation in the captopril,HSA mixture even with long-term UV-B exposure, but captopril might interact with HSA to change the protein secondary structure of HSA whether there was UV-B irradiation or not. The pH of the buffer solution and captopril,HSA interaction may play more important roles in transforming the secondary structure of HSA from ,-helix to ,-sheet in the corresponding captopril,HSA mixture than UV-B exposure. The present study also implies that HSA has the capability to protect the instability of captopril in the course of UV-B irradiation. In addition, a partial unfolding of HSA induced by pH or captopril-HSA interaction under UV-B exposure is proposed. [source]

    Laser Flash Photolysis in a O3/Cl2 Mixture at 266 nm in a Very Low-Pressure Flow System,

    PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 4 2005
    Jorge Codnia
    ABSTRACT The laser flash photolysis in a very low-pressure flow system with mass spectrometry detection technique was developed for the study of oxidation reactions of chlorofluorocarbons. In this work, we have studied the UV photolysis of O3 in the presence of Cl2 at room temperature, which presents two catalytic cycles of O3 depletion with efficiencies dependent on the partial pressures in the photoreactor. The ozone dissociation was initiated with fourth harmonic pulses of a Nd:YAG laser. The detection of the reactants and the final and intermediate reaction products was performed with real-time mass spectrometry. The variations of the O3, Cl2 and ClO concentration were measured. The equations system associated to a proposed kinetic scheme was solved numerically and excellent agreement with the experimental results was obtained. The results from this work allowed the determination of the wall loss rates of the O(1D), Cl and ClO radicals. [source]

    Deposition of SiO, -Like Thin Films from a Mixture of HMDSO and Oxygen by Low Pressure and DBD Discharges to Improve the Corrosion Behaviour of Steel

    PLASMA PROCESSES AND POLYMERS, Issue S1 2007
    Camille Petit-Etienne
    Abstract Hexamethyldisiloxane was used to deposit silicon dioxide thin films using a low frequency plasma reactor at low pressure as well as a dielectric barrier discharge (DBD) at atmospheric pressure. FT-IR, XPS, EIS, SEM and ellipsometry were used to analyse the samples. The results show that, at low pressure, the deposited films which are smooth, continuous and dense present a polymer-like structure. By carrying out the film deposition after an oxygen plasma pretreatment step, a further improvement in the protective properties is achieved, which is observed in the case of SiO, coatings with 13.56 MHz RF generators.1 At atmospheric pressure, the deposited films present an inorganic character deposited in open air and a polymer-like one deposited under a controlled nitrogen atmosphere in our DBD reactor. The latter also allows continuous films which present the best anti-corrosive properties (which have been studied for the first time for anti-corrosive properties) when they contain some carbon incorporated. [source]