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Coefficient
Kinds of Coefficient Terms modified by Coefficient Selected AbstractsINDIRECT GENETIC EFFECTS INFLUENCE ANTIPREDATOR BEHAVIOR IN GUPPIES: ESTIMATES OF THE COEFFICIENT OF INTERACTION PSI AND THE INHERITANCE OF RECIPROCITYEVOLUTION, Issue 7 2009Bronwyn H. Bleakley How and why cooperation evolves, particularly among nonrelatives, remains a major paradox for evolutionary biologists and behavioral ecologists. Although much attention has focused on fitness consequences associated with cooperating, relatively little is known about the second component of evolutionary change, the inheritance of cooperation or reciprocity. The genetics of behaviors that can only be expressed in the context of interactions are particularly difficult to describe because the relevant genes reside in multiple social partners. Indirect genetic effects (IGEs) describe the influence of genes carried in social partners on the phenotype of a focal individual and thus provide a novel approach to quantifying the genetics underlying interactions such as reciprocal cooperation. We used inbred lines of guppies and a novel application of IGE theory to describe the dual genetic control of predator inspection and social behavior, both classic models of reciprocity. We identified effects of focal strain, social group strain, and interactions between focal and group strains on variation in focal behavior. We measured ,, the coefficient of the interaction, which describes the degree to which an individual's phenotype is influenced by the phenotype of its social partners. The genetic identity of social partners substantially influences inspection behavior, measures of threat assessment, and schooling and does so in positively reinforcing manner. We therefore demonstrate strong IGEs for antipredator behavior that represent the genetic variation necessary for the evolution of reciprocity. [source] MEASUREMENT OF THERMAL EXPANSION COEFFICIENT OF FLEXIBLE SUBSTRATE BY MOIRÉ INTERFEROMETRYEXPERIMENTAL TECHNIQUES, Issue 3 2001B. Han First page of article [source] IMPACT OF BLENDING OF FRYING OILS ON VISCOSITY AND HEAT TRANSFER COEFFICIENT AT ELEVATED TEMPERATURESJOURNAL OF FOOD PROCESS ENGINEERING, Issue 1 2010SUKUMAR DEBNATH ABSTRACT In the present work, the effect of binary blending of five frying oils on kinematic viscosity (,) and convective heat transfer coefficient (h) was studied at elevated temperatures (170, 180 and 190C). A Cannon Ubbelhode calibrated capillary viscometer (Cannon Instrument Company, State College, PA) in a custom-designed and fabricated convective air bath heater and a highly conductive cylindrical metal transducer were used for generating,and h data, respectively. The value of,decreased from 3.617 × 10 - 6 to 2.062 × 10 - 6 m2 s - 1, and h increased from 221.0 to 301.2 Wm - 2 C - 1 by increasing the aforementioned oil temperatures. A good correlation between, (R2 > 0.996) or h (R2 > 0.987) of these frying oils and their selected binary blends with the previously mentioned temperature range was observed. Significant difference (P < 0.05) was found between different levels of parameters when treatments were compared using Tukey's test. PRACTICAL APPLICATIONS In food engineering applications, the physical properties of foods play an important role in the analysis of process parameters and in the design and fabrication of processing equipment. Determination of kinematic viscosity and convective heat transfer coefficients of frying oils and their selected blends at elevated temperatures are useful from an industrial point of view. In the present work, the effect of blending different edible oils on the kinematic viscosity and convective heat transfer coefficients at elevated temperatures was studied. Because selected blended oils provided lower levels of viscosities and higher levels of heat transfer coefficients, these results may be an attractive proposition in improving the quality of fried products and cost-effectiveness in the fried food industry. [source] DEHYDRATION CHARACTERISTICS OF PAPAYA (CARICA PUBENSCENS): DETERMINATION OF EQUILIBRIUM MOISTURE CONTENT AND DIFFUSION COEFFICIENTJOURNAL OF FOOD PROCESS ENGINEERING, Issue 5 2009R. LEMUS-MONDACA ABSTRACT This study determined the drying kinetics behavior of papaya at different temperatures (40, 50, 60, 70 and 80C). Desorption isotherms were determined at 5, 20 and 50C over a relative humidity range of 10,95%. The Guggenheim, Anderson and de Boer models were found to be suitable for description of the sorption data. The samples reached equilibrium moisture of 0.10 ± 0.01 g water/g dry matter. Fick's second law model was used to calculate the effective diffusivity (6.25,24.32 × 10 - 10 m2/s). In addition, experimental data were fitted by means of seven mathematical models. The kinetic parameters and the diffusion coefficient were temperature-dependent and were evaluated by an Arrhenius-type equation. The modified Page model obtained the best-fit quality on experimental data according to statistical tests applied. PRACTICAL APPLICATIONS The main utility of this study is the application of both different empirical models and the diffusional model in tropical fruits' dehydration, which can be considered a basis for a very accurate estimation of drying time and the optimization of the same process. Two newly mathematical models are proposed in this study, through which a good fit on the data of experimental moisture content was achieved. The study of drying of papaya cultivated in Chile engages a great technological interest, because this product is widely used in the development of different products such as candying, canning, juice, syrup and marmalade. In addition, papayas cultivated in Chile, along with other tropical fruits cultivated in Brazil, Colombia and the Caribbean, have become especially important in the exportations of these countries. The major markets for these products include the U.S.A., the European Community and Asia. [source] APPLICATION OF COEFFICIENT OF FRICTION TO THE SEPARATION OF COCOA HUSK,BEANS MIXTUREJOURNAL OF FOOD PROCESS ENGINEERING, Issue 5 2007O.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] HEAT TRANSFER COEFFICIENT FOR COOKIE SHAPED OBJECTS IN A HOT AIR JET IMPINGEMENT OVENJOURNAL OF FOOD PROCESS ENGINEERING, Issue 1 2001N. NITIN ABSTRACT Correlations for average heat transfer coefficient for cookie shaped objects in a hot air jet impingement oven were obtained using aluminum cookie models. The study was carried out in a pilot plant scale hot air jet impingement oven. The effects of individual cookie position, presence of surrounding cookies, air velocity, air temperature and rotation of the oven plate on average surface heat transfer coefficient were investigated. The value of the heat transfer coefficient ranged between 100,225 W/m2K and was found to be a strong function of jet air velocity. The impact of surrounding cookies on the heat transfer coefficient was more for smaller cookies, which had larger cookie-to-cookie spacing. [source] WATER DIFFUSION COEFFICIENT AND MODELING OF WATER UPTAKE IN PACKAGED YERBA MATEJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 4 2007LAURA A. RAMALLO ABSTRACT Effective water diffusion coefficient (Deff) was determined from the kinetics of moisture gain in a yerba mate bed. A value of 1.5 × 10,9 ± 0.4 × 10,9 m2/s was obtained at 40C and 90% relative humidity, by fitting experimental data to the series solution of Fick's second law. A model was developed to predict moisture profile and water uptake in packaged yerba mate. In order to simulate moisture gain in the packaged food, the model considers that the global process of humidity gain is controlled by combined mechanisms of package permeability, product sorption balances and water diffusion within the food bed. The explicit finite difference method was used to numerically solve the resulting equations. The validity of the model was tested by comparing predicted and experimental moisture profiles for high (WVTR , 20 g/m2/day) and low (WVTR , 400 g/m2/day) barrier packages. The model was found to adequately predict the profile of moisture content. [source] THREE-GENE IDENTITY COEFFICIENTS DEMONSTRATE THAT CLONAL REPRODUCTION PROMOTES INBREEDING AND SPATIAL RELATEDNESS IN YELLOW-CEDAR, CALLITROPSIS NOOTKATENSISEVOLUTION, Issue 10 2008Stacey Lee Thompson Asexual reproduction has the potential to promote population structuring through matings between clones as well as through limited dispersal of related progeny. Here we present an application of three-gene identity coefficients that tests whether clonal reproduction promotes inbreeding and spatial relatedness within populations. With this method, the first two genes are sampled to estimate pairwise relatedness or inbreeding, whereas the third gene is sampled from either a clone or a sexually derived individual. If three-gene coefficients are significantly greater for clones than nonclones, then clonality contributes excessively to genetic structure. First, we describe an estimator of three-gene identity and briefly evaluate its properties. We then use this estimator to test the effect of clonality on the genetic structure within populations of yellow-cedar (Callitropsis nootkatensis) using a molecular marker survey. Five microsatellite loci were genotyped for 485 trees sampled from nine populations. Our three-gene analyses show that clonal ramets promote inbreeding and spatial structure in most populations. Among-population correlations between clonal extent and genetic structure generally support these trends, yet with less statistical significance. Clones appear to contribute to genetic structure through the limited dispersal of offspring from replicated ramets of the same clonal genet, whereas this structure is likely maintained by mating among these relatives. [source] WATERSHED WEIGHTING OF EXPORT COEFFICIENTS TO MAP CRITICAL PHOSPHOROUS LOADING AREAS,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 1 2003Theodore A. Endreny ABSTRACT: The Export Coefficient model (ECM) is capable of generating reasonable estimates of annual phosphorous loading simply from a watershed's land cover data and export coefficient values (ECVs). In its current form, the ECM assumes that ECVs are homogeneous within each land cover type, yet basic nutrient runoff and hydrological theory suggests that runoff rates have spatial patterns controlled by loading and filtering along the flow paths from the upslope contributing area and downslope dispersal area. Using a geographic information system (GIS) raster, or pixel, modeling format, these contributing area and dispersal area (CADA) controls were derived from the perspective of each individual watershed pixel to weight the otherwise homogeneous ECVs for phosphorous. Although the CADA-ECM predicts export coefficient spatial variation for a single land use type, the lumped basin load is unaffected by weighting. After CADA weighting, a map of the new ECVs addressed the three fundamental criteria for targeting critical pollutant loading areas: (1) the presence of the pollutant, (2) the likelihood for runoff to carry the pollutant offsite, and (3) the likelihood that buffers will trap nutrients prior to their runoff into the receiving water body. These spatially distributed maps of the most important pollutant management areas were used within New York's West Branch Delaware River watershed to demonstrate how the CADA-ECM could be applied in targeting phosphorous critical loading areas. [source] POPULATION EXTINCTION IN DETERMINISTICAND STOCHASTIC DISCRETE-TIME EPIDEMIC MODELS WITH PERIODIC COEFFICIENTS WITH APPLICATIONS TO AMPHIBIAN POPULATIONSNATURAL RESOURCE MODELING, Issue 2 2006KEITH E. EMMERT ABSTRACT. Discrete-time deterministic and stochastic epidemic models are formulated for the spread of disease in a structured host population. The models have applications to a fungal pathogen affecting amphibian populations. The host population is structured according to two developmental stages, juveniles and adults. The juvenile stage is a post-metamorphic, nonreproductive stage, whereas the adult stage is reproductive. Each developmental stage is further subdivided according to disease status, either susceptible or infected. There is no recovery from disease. Each year is divided into a fixed number of periods, the first period represents a time of births and the remaining time periods there are no births, only survival within a stage, transition to another stage or transmission of infection. Conditions are derived for population extinction and for local stability of the disease-free equilibrium and the endemic equilibrium. It is shown that high transmission rates can destabilize the disease-free equilibrium and low survival probabilities can lead to population extinction. Numerical simulations illustrate the dynamics of the deterministic and stochastic models. [source] Reducing the Coefficient of Friction for Fast-Absorbing Gut SutureDERMATOLOGIC SURGERY, Issue 12 2009JONATHAN LEE BINGHAM MD No abstract is available for this article. [source] Comparative Ant Faunas between Seonyudo and Seven Other Islands of West Sea in KoreaENTOMOLOGICAL RESEARCH, Issue 2 2002So-Jin HA ABSTRACT This paper is intended as an investigation of the biogeographic characteristics of ant faunas of the eight islands in West Sea of South Korea, using quantitative genetic analyses. The faunal similarity is examined using the Nomura-Simpson's Coefficient (NSC). The obtained NSC value matrix was examined by a cluster analysis using UPGMA method. The MSC-values between the seven areas investigated range from 0.500 (Deokjeokdo Hongdo) to 0.909 (Wonsando-Hongdo). In these islands including Seonyudo, the NSC -values range from 0.571 (Deokjeokdo) to 0.778 (Bigeumdo). The cluster analysis using the similarity index (NSC) showed that eight islands were divided into two groups at the level of 41%. It was shown that Wonsando and Bigeumdo were closer (Similarity = 83%) than those between others. Deokjeokdo and Bigeumdo were remote (Similarity = 41%) from each conspecific population. That is, the species composition of Bigeumdo (Similarity = 70%) was similar to that of the Seonyudo, while that of Deokjeokdo (Similarity = 41%) was different from that. [source] Faunal Comparison of Ants among Cheongsando and Other Islands of South Sea in KoreaENTOMOLOGICAL RESEARCH, Issue 1 2002Seong-Joon PARK ABSTRACT This paper attempts to reveal the biogeographic characteristics of ant fauna of the islands among Korean South Sea, using quantitative analyses. The data treated in this paper are those from Cheongsando Is. and 10 other islands in South Sea which have been well investigated. The faunal similarity is examined using the Nomura-Simpson's Coefficient (NSC). Futhermore, the obtained NSC value matrix is examined by a cluster analysis using UPGMA method. The number of species which has been recorded in the 11 islands are 91 species belonging to 34 genera under 4 subfamilies. Among the above 11 islands, Jejudo Is., which is the largest, has the highest number of species, 67 spp., while Geogeumdo Is. has the lowest, 21 spp. Cheongsando Is. which has directly been investigated by authors has 30 species. The NSC- values between the 11 localities investigated range from 0.522 (Wando Is. to Saryangdo Is.) to 1.000 (Namhaedo Is. to Geojedo Is.). The comparative NSC value of Cheongsando Is. and 10 islands range from 0.522 (to Saryangdo Is.) to 0.833 (to Jejudo Is). The cluster analysis using a similarity index (NSC) showed that the islands of these areas could be grouped into 3, a level of 32%. The similarity of Soando Is. and Geomundo Is. were the closest, 63%, while Soando Is. and Namhaedo Is. were the remotest, 32%. The similarity of Jindo Is. and Cheongsando Is, was 63%, while that of Namhaedo Is. and Cheongsando Is. was 32%. [source] Heat-Transfer Coefficient for Cellular Materials Modelled as an Array of Elliptic Rods,ADVANCED ENGINEERING MATERIALS, Issue 10 2009Marcelo J. S. de Lemos Convective heat-transfer coefficients in foam-like materials, modelled as an array of elliptic rods, are numerically determined. An incompressible fluid is considered, flowing through an infinite foam-like material with an arbitrary solid temperature. A repetitive cell is identified and periodic boundary conditions are applied. Turbulence is handled with both low and high Reynolds number formulations. The interfacial heat-transfer coefficient is obtained by volume integrating the distributed variables obtained within the cell. The results indicate that, for the same mass-flow rate, materials formed by elliptic rods have a lower interfacial heat-transfer coefficient compared to other media modelled as staggered arrays of square rods. [source] On Storage Coefficient and Vertical StrainGROUND WATER, Issue 3 2006T.N. Narasimhan First page of article [source] Relationship between Contact Voltage Drop and Frictional Coefficient under High-current Sliding ContactIEEJ TRANSACTIONS ON ELECTRICAL AND ELECTRONIC ENGINEERING, Issue 4 2010Takahiro Ueno Member Abstract Large DC motors are used in various industrial applications. These motors repeatedly generate arcs between the brush and commutator, because the load change is intense and the current value is also large. In particular, for the case in which the current is concentrated on a part of the brush, brush burnout may occur as a result of overcurrent. Therefore, excellent brushes to withstand arc generation and with good electrical properties are required. In the present paper, we discuss the relation between contact voltage drop and frictional wear for electrical sliding contacts when high currents flow to the brush. Specifically, we investigate the means by which to prevent brush burnout when high-current flows to the brush. Copyright © 2010 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [source] Positive Temperature Coefficient of Resistivity in Donor-Doped BaTiO3 Ceramics derived from Nanocrystals synthesized at Low Temperature,ADVANCED MATERIALS, Issue 5 2008L. Brutchey Small, donor-doped Ba1- xLaxTiO3nanocrystals are successfully prepared for the first time. These nanocrystals are suitable precursors for small-grain Ba1- xLaxTiO3 ceramics with a sizeable positive temperature coefficient of resistivity (PTCR) that is comparable to that of traditional large-grain ceramics derived from solid-state routes. [source] Flow cytometric method for simultaneous assay of foetal haemoglobin containing red cells, reticulocytes and foetal haemoglobin containing reticulocytesINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 3 2001Y. Mundee Level of foetal haemoglobin (HbF) containing red cells (F cells) is a parameter for monitoring sickle cell anaemia (SS) patients undergoing treatment with HbF modulating drugs (including hydroxyurea (HU)). One convenient technique for F cell assay is flow cytometry. A flow cytometric method for the simultaneous assay of F cells, reticulocytes and HbF-containing reticulocytes (F reticulocytes) is described in this paper. These three parameters can be obtained within 2 h using double colour staining flow cytometry. Glutaraldehyde fixation, Triton X-100 permeabilization, monoclonal antibody to HbF Tri-colour® conjugate (MoAb-HbF-TC; deep-red fluorescence) immuno-staining and thiazole orange (TO; green fluorescence) are employed. The red cell gate was set on forward scatter (FSC) and logarithmic side scatter (logSSC) for 50 000 cells on the flow cytometer. Fluorescent signals were acquired from fluorescent channel 1 (FL1; green) and (FL4; deep-red). Coefficient of variation percent (%CVs) of intra- and inter-assay were less than 9% and 15%, respectively. EDTA, citrate, heparin and CTAD anticoagulants are all suitable; the samples can be stored at 4°C for up to 6 days. The method is a simple, rapid, convenient, reproducible and useful way of determining F cell, reticulocyte and F reticulocyte levels in sickle cell and thalassaemic patients. [source] Cytomegalovirus and cyclosporin-induced gingival overgrowth in children with liver graftsINTERNATIONAL JOURNAL OF PAEDIATRIC DENTISTRY, Issue 4 2002M.-T. Hosey Summary., Objective. To determine whether cytomegalovirus (CMV) is associated with gingival overgrowth in paediatric liver graft recipients treated with cyclosporin. Study design. Thirty-four children, 25 of whom were under 5 years of age, who had undergone liver transplantation, were examined. An Index of Severity of Gingival Overgrowth was used to measure the prevalence and severity of the gingival overgrowth. The trough cyclosporin level was recorded and the CMV status of the patient matched to the dental findings. The association between the severity of gingival overgrowth and CMV infection was examined using the contingency coefficient. An anova was used to assess the association between the circulating trough cyclosporin concentration and the severity of gingival overgrowth. Pearson's Product Moment Correlation Coefficient was used to examine the association between the duration of exposure to cyclosporin and the severity of gingival overgrowth. Results. There was a significant inverse association between the duration of exposure to cyclosporin and the severity of gingival overgrowth. There was no relationship between the trough cyclosporin concentration and the severity of gingival overgrowth. There was no association between CMV and gingival overgrowth. Conclusion. Gingival overgrowth was related to the duration of cyclosporin therapy but was neither more prevalent nor more severe in subjects who were CMV seropositive. [source] Measuring effectiveness of TQM training: an Indian studyINTERNATIONAL JOURNAL OF TRAINING AND DEVELOPMENT, Issue 3 2003Sasmita Palo Total Quality Management (TQM) is a never ending process of improving work processes. It operates according to the premise that organisations cannot rest comfortably without continuously improving whatever is being done. There has to be a culture of continuous improvement and everyone in the organisation must strive towards it. This could be accomplished only through continuous training. The present study seeks to examine the role of training as well as measuring its effectiveness for successful implementation of TQM. For this purpose, data have been retrieved from a public sector enterprise manufacturing crude steel in India. The findings of the study are based purely on primary survey. Pearson's Correlation Coefficient with their significance levels have been used to measure the effectiveness of TQM training and the correlation between TQM training and selected factors. The authors have found that training creates awareness, builds employees' commitment to quality policy and strategy, facilitates teamwork, enhances performance standards, and bolsters the skills and abilities of employees. However, the organisation needs to focus more upon improving communication competencies, multiple skill development and customer value training. Successful TQM training in the organisation needs more budgetary allocation and commitment, support and enthusiasm of the top management. [source] Comparison of total tract digestibility, development of visceral organs and digestive tract of Mong cai and Yorkshire × Landrace piglets fed diets with different fibre sourcesJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 2 2009N. T. Len Summary The aim of the study was to evaluate the effects of piglet age and dietary fibre source on the development of visceral organs and the gastrointestinal tract (GIT), and on growth performance and total tract apparent digestibility (TTAD) in local [pure-breed Mong cai (MC)] and exotic [Landrace × Yorkshire (LY)] piglets. The experimental diets contained different fibre sources: C (basal diet), RB (basal diet + rice bran), SPVM (basal diet + sweet potato vine meal) and CReM (basal diet + cassava residue meal). The neutral detergent fibre (NDF) content in diet C and the fibrous diets was 8.8% and 17.1%,17.7% respectively (dry matter basis). Collection of faecal samples to determine TTAD was carried out for five consecutive days before the experiment was finished (63 days). The piglets were killed at the age of 10 days (before being given the same solid feed), 30 days (weaning, 20 days after solid feed introduced) and 63 days (33 days after being given the different fibrous diets) when the length of intestinal segments, weight of organs (liver, heart, kidneys) and empty weight of the GIT (stomach, small intestine, caecum and colon + rectum) were measured. As the age of animals increased, the relative weight of organs and the length of intestines (expressed on a mass-specific basis) decreased (p < 0.05), and the weight of GIT increased (p < 0.001). The piglets fed fibrous diets had heavier GIT than those fed diet C with the highest values in CReM (p < 0.05). The colon + rectum length was not significantly different among C, RB and SPVM, but was shorter than in CReM (p < 0.05). Coefficient of total tract apparent digestibility (CTTAD) of nutrients in the fibrous diets was lower than in C (p < 0.01). Average daily gain (ADG) and feed conversion ratio (FCR) in C, RB and CReM were not different and were better than in SPVM (p < 0.01). There were no significant differences in the weights of organs between the two breeds at day 10, 30 and 63 (p > 0.05). The weight and length of GIT were not significantly different between the two breeds at day 10 and day 30, but were greater for MC at day 63. The caecum and colon + rectum at 10 and 30 days were longer in MC than in LY (p < 0.001). The relative development of GIT post-weaning was higher than pre-weaning, the difference being most apparent in MC. As a result at 63 days, MC had heavier visceral organs and GIT, and longer intestines on fibrous diets than LY (p < 0.05). The MC at 63 days had higher CTTAD of organic matter, gross energy, crude fibre and NDF (p < 0.001) and ether extract and crude protein (p < 0.05), but lower ADG and poorer FCR than LY (p < 0.001). It can be concluded that the GIT of the MC piglets developed more rapidly than LY when they were introduced to solid feed, and that the difference was more marked on the fibrous diets and after weaning, which resulted in higher total tract digestibility of nutrients in MC compared with LY. Cassava residue meal was better digested than RB and SPVM, and supported higher live weight gains. [source] Water Apparent Diffusion Coefficient and T2 Changes in the Acute Stage of Maple Syrup Urine Disease: Evidence of Intramyelinic and Vasogenic-Interstitial EdemaJOURNAL OF NEUROIMAGING, Issue 2 2003Andrea Righini MD ABSTRACT Background. The acute phase of the neonatal classical form of maple syrup urine disease (MSUD) is usually associated with generalized brain edema. Methods and Results. The authors present the case of a newborn infant in the acute stage of the classical form of MSUD in whom a remarkable decrease in the water apparent diffusion coefficient (ADC) in advanced myelinating white matter areas was associated with an increase in the T2 signal. This diffusion magnetic resonance imaging (MRI) pattern appears to be compatible with a rare kind of cytotoxic edema, the so-called intramyelinic edema. At the same time, an increase in the ADC was seen in unmyelinated areas together with an increase in the T2 signal, a sign of a coexistent vasogenic-interstitial edema. Conclusions. ADC measurements in MSUD provide more specific information than conventional MRI about the pathophysiology of white matter changes. [source] Ciclopirox delivery into the human nail plateJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 10 2004Xiaoying Hui Abstract The human nail penetration of the antifungal ciclopirox was determined for marketed gel containing 0.77% of ciclopirox, an experimental gel containing 2% of ciclopirox, and a marketed lacquer containing 8% of ciclopirox. After 14 days dosing, unabsorbed drug remaining on the surface, drug within the infection-prone area, and the amount that had penetrated through the nail were determined. Ciclopirox delivery into and through the nail was significantly greater from the marketed gel, than from either the experimental gel or the nail lacquer (p,<,0.05). In addition, the surface nail contained more unabsorbed drug from the lacquer. Further, the drug penetrating into and through the nail was also greater from the marketed gel, leading to a higher Calculated Efficacy Coefficient for the marketed gel, than from the marketed lacquer or the experimental gel. The formulation plays an important role in the enhancement of ciclopirox permeation into and through the human nail plate, and the concentration of ciclopirox in the formulation was not a factor in determining penetration. © 2004 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 93:2545,2548, 2004 [source] Liquid chromatography,tandem mass spectrometry method for simultaneous determination of cyclosporine A and its three metabolites AM1, AM9 and AM4N in whole blood and isolated lymphocytes in renal transplant patientsJOURNAL OF SEPARATION SCIENCE, JSS, Issue 15 2010Hana Brozmanová Abstract A LC-MS/MS method was developed and validated for the determination of cyclosporine A (CsA) and its three phase 1 metabolites AM1, AM9, and AM4N in whole blood and lymphocytes isolated on the Histopaque gradient. 200,,L of whole blood was precipitated with 10,mol/L zinc sulfate in acetonitrile/methanol (40:60, v/v) and lymphocytes isolated from 1.5,mL blood were extracted with acetonitrile/methanol (40:60, v/v). The analytes and internal standard cyclosporine D were separated on RP column BEH C18, 2.1×50,mm, 1.7,,m using gradient LC-MS/MS analysis in positive electrospray mode. Time of analysis was 5,min. Linearity in blood was 5,2000,,g/L for CsA, AM1, and AM9; 2,500,,g/L for AM4N; and 2,500,,g/L for all substances in lymphocytes. Coefficient of variations was 1.8,9.8% and recovery was 92.0,110.0%. The method was used in early and chronic renal transplant patients for therapeutic drug monitoring of CsA to compare either its share in lymphocytes as target organ or binding to one lymphocyte. The same parameters were calculated for all metabolites tested. [source] Large Piezoelectric Coefficient in Tb-Doped BiFeO3 FilmsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 4 2010Xuemei Chen Polycrystalline BiFeO3 and Bi1,xTbxFeO3 (BTFO) (x=0.05,0.16) thin films were deposited on indium tin oxide/glass substrates via a metal organic deposition method. The influence of Tb doping content on the structure and multiferroic properties was investigated. X-ray diffraction results reveal that there may exist a structure transition around x=0.11 in the BTFO system. Well-saturated and rectangular P,E hysteresis loops can be observed in all BTFO films. The BTFOx=0.11 film exhibits the maximum values of the remanent out-of-plane piezoelectric coefficient (d33=140 pm/V) and saturated magnetization (Ms=22.2 emu/cm3). [source] Influence of Ba/Ti Ratio on the Positive Temperature Coefficient of Resistivity Characteristics of Ca-Doped Semiconducting BaTiO3 Fired in Reducing Atmosphere and Reoxidized in AirJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 6 2007Hideaki Niimi The positive temperature coefficient of resistivity (PTCR) characteristics of donor-doped BaTiO3 fired in a reducing atmosphere and reoxidized in air are investigated. The result reveals that conventional semiconducting BaTiO3 ceramics fired in a reducing atmosphere and reoxidized at a low temperature of 800°C in air show minimal PTCR characteristics, as reported earlier; however, Ca-doped BaTiO3 with compositions in the range of 1.005,(Ba+Ca+La)/Ti,1.010 exhibit pronounced PTCR characteristics, even when reoxidized at such a low temperature. The semiconducting BaTiO3 ceramics with {(Ba+Ca+La)/Ti}=1.005 and Ca-doped to 20 mol% exhibit remarkable PTCR characteristics with a resistivity jump of two orders of magnitude when they have been reoxidized at 800°C after firing in a reducing atmosphere. [source] Adhesive-Bonded Ca(Mg1/3Nb2/3)O3/Ba(Zn1/3Nb2/3)O3 Layered Dielectric Resonators with Tunable Temperature Coefficient of Resonant FrequencyJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 10 2006Lei Li No abstract is available for this article. [source] Positive Temperature Coefficient of Resistivity Effect in Highly Donor,Doped Barium TitanateJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 6 2001Darko Makovec BaTiO3 ceramics doped with different La concentrations (0,12 mol%) were prepared by sintering under the reducing conditions of a nitrogen atmosphere containing 1% hydrogen. The critical donor concentration that causes blocking of the exaggerated grain growth was observed to be ,10 mol% La. The samples, which were semiconducting after sintering under reducing conditions, were subsequently reoxidized by annealing in air to induce the positive temperature coefficient of resistivity (PTCR) effect. After reoxidation at 1150°C a noticeable PTCR effect was observed in the samples doped with La concentrations as high as 2.5 mol%. The room-temperature resistivity after reoxidation was found to increase with increasing donor concentration due to an increase in the thickness of the insulating layers at the grain boundaries. TEM analysis showed that reoxidation of the samples caused precipitation of the Ti-rich compound Ba6Ti17O40 inside the doped BaTiO3 -matrix grains. [source] Relationship between the Bond Valence and the Temperature Coefficient of the Resonant Frequency in the Complex Perovskite (Pb1,xCax)[Fe0.5(Nb1,yTay)0.5]O3JOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 1 2001Heung Soo Park The temperature coefficient of the resonant frequency (TCF) of complex perovskite (Pb1,xCax)[Fe0.5(Nb1,yTay)0.5]O3 ceramics (x= 0.5, 0.55; 0.0 ,y, 1.0) was investigated, relative to the bond valence of the A- and B-site ions in the ABO3 perovskite structure (such as the barium-, strontium-, and calcium-based complex perovskites). The TCF of these complex perovskite compounds varied with the bond valence of the A- and B-sites and the tolerance factor (t) in the perovskite structure. In the tilted region (t < 1.0), the tilting of the oxygen octahedra increased and the TCF decreased, because of the increased bond valence of the B-site. Also, the dependence of TCF on the bond valence of the A-site was similar to its dependence on t. [source] Preliminary study on the use of near-infrared reflectance spectroscopy to assess nitrogen content of undried wheat plantsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 1 2007Alejandro Morón Abstract Near-infrared reflectance (NIR) spectroscopy combined with chemometrics was used to assess nitrogen (N) and dry matter content (DM) and chlorophyll in whole-wheat plant (Triticum aestivum L). Whole-wheat plant samples (n = 245) were analysed by reference method and by visible and NIR spectroscopy, in fresh (n = 182) and dry (n = 63) presentations, respectively. Calibration equations were developed using partial least squares (PLS) and validated using full cross-validation (leave-one-out method). Coefficient of determination in calibration (R2CAL) and the standard error of cross-validation (SECV) for N content in fresh sample presentation, after second derivative, were 0.89 (SECV: 0.64%), 0.86 (SECV: 0.66%) and 0.82 (SECV: 0.74%) using the visible + NIR, NIR and visible wavelength regions, respectively. Dry sample presentation gave better R2CAL and SECV for N compared with fresh presentation (R2CAL > 0.90, SECV < 0.20%) using visible + NIR. The results demonstrated that NIR is a suitable method to assess N concentration in wheat plant using fresh samples (unground and undried). Copyright © 2006 Society of Chemical Industry [source] | ||||||||||||||||||||||||||||||||||||||||||||||||||||