Different Products (different + products)

Distribution by Scientific Domains
Distribution within Chemistry


Selected Abstracts


The Thermal Decomposition of Three Magnetic Acetates at Their Autogenic Pressure Yields Different Products.

EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 14 2007

Abstract We report on the one-stage, reproducible, solvent-free, competent and straightforward approach for the synthesis of fullerene-like Ni@C, Co@C, and Fe3O4@C core-shell nanostructures that can be scaled up. The single precursor reactions of low cost acetates of Fe, Co and Ni are separately conducted at a relatively low temperature (700 °C) in a closed Swagelok reactor, as compared to other methods for the formation of graphitic layers. It is worth mentioning that although identical reaction parameters are employed, using the three acetate precursors, the graphitic carbon is coated on nanosized metallic Ni and Co cores, while Fe tends to form Fe3O4, maintaining the same core-shell morphology. The systematic morphological, compositional, structural characterization and the room temperature magnetic susceptibility measurements of the as-made particles are carried out on a vibrating sample magnetometer. The plausible mechanism is based on the comparison between the dissociation products of three acetate precursors, their obtained experimental data, and calculations on the enthalpy and free energy changes.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source]


A Facile Reduction of Azoxyarenes with Hydrazine Hydrate/Magnesium: Formation of Different Products under Different Reaction Conditions.

CHEMINFORM, Issue 14 2006
Hemmaragala M. Nanjundaswamy
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source]


Fragrance contact allergic patients: strategies for use of cosmetic products and perceived impact on life situation

CONTACT DERMATITIS, Issue 6 2009
Susan Hovmand Lysdal
Background: Fragrance ingredients are a common cause of contact allergy. Very little is known about these patients' strategies to manage their disease and the effect on their daily lives. Objectives: To investigate if patients with diagnosed fragrance contact allergy used scented products, how they identified tolerated products, and if fragrance allergy affected their daily living. Method: One hundred and forty-seven patients diagnosed with fragrance contact allergy in a 20-month period were included and received a postal questionnaire concerning the subjects of the study. One hundred and seventeen (79.6%) replied. Results: In total, 53/117 (45.3%) responded that they had found some scented products that they could tolerate. Thirty-seven (31.6%) had not tried to find any scented products and 26 (22%) had tried but could not find any. The methods most often used were trying different products and reading the ingredient label. Of the total respondents, 17.1% reported sick-leave due to fragrance allergy and 45.3% found that fragrance allergy significantly affected their daily living. Conclusion: Many patients with fragrance contact allergy succeeded in finding some scented products, which they could tolerate, e.g. by use of ingredient labelling, but a significant proportion had continued skin problems. Almost half of the patients perceived that fragrance allergy significantly affected their daily lives. [source]


Analyses of alkaloids in different products by NACE-MS

ELECTROPHORESIS, Issue 22 2007
Chen-Wen Chiu
Abstract A simple method for the separation and characterization of five nicotine-related alkaloids by NACE employing UV and MS detections is described here for the first time. Several factors, including NACE parameters (compositions of running solution) and MS parameters (such as nature and flow rate of sheath liquid, pressure of nebulization gas, and flow rate of dry gas), were optimized in order to obtain both an adequate CE separation and high MS signals for the alkaloid compounds used in this study. A reliable CE separation of five alkaloids was achieved in 50,mM ammonium formate that was dissolved in an ACN/methanol mixture (50:50, v/v) of pH*,4.0 (apparent pH 4.0). The optimal electrospray MS measurement was carried out in the positive ionization mode using a coaxial sheath liquid composed of isopropyl alcohol and water in the ratio of 80:20 v/v at a flow rate of 180,,L/h. In addition, the proposed NACE method was also applied in the analyses of alkaloids in several products including chewing gums, beverages, and tobaccos. This NACE-MS method was found to provide a better detection ability and separation resolution for the analysis of nicotine alkaloids when compared to other aqueous CE-MS reports. [source]


Energy tax harmonization in the European Union: a proposal based on the internalization of environmental external costs

ENVIRONMENTAL POLICY AND GOVERNANCE, Issue 1 2002
Susanna Dorigoni
Energy tax harmonization represents a fundamental target within the European Union. In fact fiscal harmonization is a crucial step towards the creation of a single market. In this article the possibility of achieving such an objective is discussed. The paper consists of two sections. In the first the European taxation on energy products is analysed. This analysis is useful in showing the differences that exist between the European countries that account for the difficulties met so far in the process of harmonization. In this respect we comment on the recent proposal of the Directive of the European Union, which lays down the obligation of minimum levels of taxation in all European member states. In the second section, after simulating the effects related to the adoption of a common environmental taxation (a first best solution based on the internalization of environmental external costs), we propose, as a second best solution, an excise tax harmonization model taking into consideration the specificity of each country and being, as far as possible, coherent with the environmental objective. This model proposes: the introduction of a minimum level of taxation on all products equal to the external cost due to the greenhouse effect (a common carbon tax); the possibility, given to the member states, of deviating from such minimum levels, in accordance with their specific requirements, internalizing in the price of the different products, by means of taxes additional to that CO2 minimum, the external costs associated with other pollutant agents (the same in all countries); the opportunity, in case it should be necessary to exceed the entire external cost, for the member states to apply increases that are in accordance with the environmental objective. Copyright © 2002 John Wiley & Sons, Ltd. and ERP Environment [source]


Prediction of heat release in the single burning item test

FIRE AND MATERIALS, Issue 2 2002
Anne Steen Hansen
This paper presents a modification of an existing mathematical model that uses cone calorimeter test results to predict heat release rate in the single burning item (SBI) test. A method for classification of cases based on multivariate statistical analysis is incorporated in the modified model. This makes it possible to determine the development of the heat release curve in the SBI test with better precision than the original version was able to. The model has been applied to 100 cases of cone calorimeter test results from 33 different products. For most of the products the predicted shape and level of the heat release curves are close to measurements in the SBI test. Using the predicted heat release results as input to calculation of FIGRA0.2MJ and THR600s within the new European system for reaction-to-fire classification, we were able to predict membership of the correct class in 90% of the analysed cases. Copyright © 2002 John Wiley & Sons, Ltd. [source]


New Insights on Near-Infrared Emitters Based on Er-quinolinolate Complexes: Synthesis, Characterization, Structural, and Photophysical Properties,

ADVANCED FUNCTIONAL MATERIALS, Issue 14 2007
F. Artizzu
Abstract Erbium quinolinolates, commonly assumed to be mononuclear species with octahedral co-ordination geometry, have been proposed as promising materials for photonic devices but difficulties in obtaining well defined products have so far limited their use. We report here the conditions to obtain in high yields three different kinds of pure neutral erbium quinolinolates by mixing an erbium salt with 8-quinolinol (HQ) and 5,7-dihalo-8-quinolinol (H5,7XQ: X,=,Cl and Br): i),the trinuclear complex Er3Q9 (1) which is obtained with HQ deprotonated by NH3 in water or ethanol/water mixtures; ii),the already known dimeric complexes based on the unit [Er(5,7XQ)3(H2O)2] [X,=,Cl (2) and Br (3)]; iii) the mononuclear [Er(5,7XQ)2(H5,7XQ)2Cl] [X,=,Cl (4) and Br (5)] complexes, obtained in organic solvents without base addition, where the ion results coordinated to four ligands, two deprotonated chelating, and two as zwitterionic monodentate oxygen donors. These results represent a further progress with respect to a recent reinvestigation on this reaction, which has shown that obtaining pure and anhydrous octahedral ErQ3, the expected reaction product, is virtually impossible, but failed in the isolation of 1 and of the neutral tetrakis species based on H5,7XQ ligands. Structural data provide a detailed description of the molecules and of their packing which involves short contacts between quinoxaline ligands, due to ,,, interactions. Electronic and vibrational studies allow to select the fingerprints to distinguish the different products and to identify the presence of water. The structure/property relationship furnishes a satisfactory interpretation of the photo-physical properties. Experimental evidence confirms that the most important quenchers for the erbium emission are the coordinated water molecules and shows that the ligand emission is significantly affected by the ,,, interactions. [source]


Elastohydrodynamics of tensioned web roll coating process

INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 6 2003
M. S. Carvalho
Abstract Coating process is an important step in the manufacturing of different products, such as paper, adhesive and magnetic tapes, photographic films, and many other. The tensioned web roll coating is one the several methods used by different industries. It relies on the elastohydrodynamic action between the fluid and the tensioned substrate for transferring and applying the liquid. The main advantage of this method is its ability to apply very thin liquid layers with less sensitivity to mechanical tolerance at relative small cost. Despite its industrial application, theoretical analysis and fundamental understanding of the process are limited. This work analyses this elastohydrodynamic action by solving the differential equations that govern the liquid flow, described by the Navier,Stokes equation, and the web deformation, modelled by the cylindrical shell approximation. The goal is to determine the operating conditions at which the process is two dimensional and defect free. The equations are discretized by the Galerkin/finite-element method. The resulting non-linear system of equations is solved by Newton's method coupled with pseudo-arc-length continuation in order to obtain solutions around turning points. The theoretical results are used to construct an operating window of the process that is in agreement with limited experimental data. Copyright © 2003 John Wiley & Sons, Ltd. [source]


Freezing time calculations for various products

INTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 12 2003
Esmail M. A. Mokheimer
Abstract This article presents a numerical simulation that estimates the freezing time for different products. In this regard, the freezing process is mathematically modelled by transient heat conduction equations that incorporate the physical properties of the three distinct regions that exist during a freezing process. These regions are namely, the solid phase region, the liquid phase region and the interface region. This model is experimentally validated and used to estimate the freezing time for three different food products, which are namely, fish balls, cherry juice and peas balls. The freezing times estimated numerically through the present model agree well with those reported in the literature and are in excellent agreement with the experimental data. Copyright © 2003 John Wiley & Sons, Ltd. [source]


Supply of over-the-counter weight-loss products from community pharmacies

INTERNATIONAL JOURNAL OF PHARMACY PRACTICE, Issue 6 2009
Anna-Maria Andronicou
Abstract Objectives The aim was to ascertain the availability of over-the-counter (OTC) weight-loss products from community pharmacies and other retail outlets in a large conurbation, and to determine the knowledge and practices of pharmacy staff in the supply of OTC weight-loss products. Method The setting was one primary care trust in England. We used a cross-sectional survey of 123 community pharmacies, 12 health stores and 64 supermarkets, plus telephone interview of the pharmacists. Key findings Over two-thirds of community pharmacies (69%) and health stores (67%) but few supermarkets (8%) stocked one or more OTC weight-loss products. In total, 73 different products were available from pharmacies, most of which (50) were claimed by manufacturers to be appetite suppressants. Seventy-eight pharmacists were interviewed, of whom 57 stocked OTC weight-loss products. Of these 57, only two claimed to undertake any measurements before supplying the products and 33 had no supporting materials/information about the products, although 38 claimed to provide advice. None of the 57 pharmacists had undertaken any specific training in relation to weight loss. Only 44% of all those interviewed considered OTC weight-loss products to be useful, with even fewer (35%) considering them to be safe. Conclusions Community pharmacies are a major distributor of OTC weight-loss products, despite the lack of evidence of their efficacy and concerns about their safety. Many pharmacists had limited knowledge of the products, placed few restrictions on their supply and viewed training in weight loss as unnecessary. Pharmacists should consider the appropriateness of supplying these products and utilize the opportunities presented to support weight reduction by more effective means. [source]


Use of over-the-counter medicines in children

INTERNATIONAL JOURNAL OF PHARMACY PRACTICE, Issue 4 2003
John McIntyre senior lecturer in child health
ABSTRACT Objective To assess the reasons for over-the-counter (OTC) medicine use in children and the sociodemographic factors influencing this choice of self-care rather than GP consultation. Method Questionnaires were sent to the home address of a randomly generated list of children under 12 years of age from three GP practices in the East Midlands selected to represent bottom, middle and top tertiles of deprivation on the basis of the Jarman score. Analysis using chi-square and Mann-Whitney tests was used to identify associated factors (number of carers in the home, number of children, deprivation score, parent/carer's age, age and number of children in the house) of the responses. Setting Primary care setting in the East Midlands region of England. Key findings From 424 completed questionnaires returned (response rate 61%), 413 parents/carers had purchased OTC medicines. Fifty-one different products had been purchased, with analgesic/antipyretic and cough/cold remedies the most frequently bought. The most commonly reported reasons for parent/carer initiated medication were to avoid troubling the GP with minor childhood ailments (79% of respondents) and to have medicines available in case of future need (74%). Cost was a barrier to buying OTC medicines for the more deprived. Advice-seeking behaviour was associated with the symptom, the number of children, affluence and the age of the child. Conclusion Parent/carer initiated use of OTC medication is widespread, particularly for analgesic/antipyretic and cough/cold remedies. Differences in advice-seeking behaviour are associated with the presenting symptom and a variety of sociodemographic factors. [source]


DEHYDRATION CHARACTERISTICS OF PAPAYA (CARICA PUBENSCENS): DETERMINATION OF EQUILIBRIUM MOISTURE CONTENT AND DIFFUSION COEFFICIENT

JOURNAL OF FOOD PROCESS ENGINEERING, Issue 5 2009
R. 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]


OPTIMIZATION CRITERIA FOR BATCH RETORT BATTERY DESIGN AND OPERATION IN FOOD CANNING-PLANTS

JOURNAL OF FOOD PROCESS ENGINEERING, Issue 6 2003
R. SIMPSON
ABSTRACT Optimization of thermal processing in the commercial sterilization of canned foods is of great interest because the canning industry plays an important role within the economy of the food processing sector. Many food canning plants operate in a batch mode with a battery of individual batch retorts. The aim of this study was to propose and analyze several criteria and methodologies for optimum design and operation of such retort systems. Two criteria were proposed in the case of choosing the optimum number of retorts to be installed when designing a new batch-operated canning line. The third criterion dealt with seeking optimum process conditions for maximizing output from a fixed number of retorts when processing small batches of different products and container sizes. In the case of new plant design optimization, one objective was to determine the optimum number of retorts that would minimize on-going processing costs related to labor and energy. Retort scheduling (programming) was studied from which a simple mathematical expression was derived for this purpose. A second objective was to determine the optimum number of retorts that would maximize the net present value of initial investment. Approaches based upon engineering economics were studied from which to develop a mathematical procedure for this purpose. In the case of maximizing output from a fixed number of retorts for different products and container sizes, isolethal processes were identified for various product/containers from which a common set of process conditions could be chosen for simultaneous processing of different product lots in the same retort. [source]


Inactivation of Food Spoilage Microorganisms by Hydrodynamic Cavitation to Achieve Pasteurization and Sterilization of Fluid Foods

JOURNAL OF FOOD SCIENCE, Issue 9 2007
P.J. Milly
ABSTRACT:, Hydrodynamic cavitation is the formation of gas bubbles in a fluid due to pressure fluctuations induced by mechanical means. Various high-acid (pH , 4.6) fluid foods were processed in a hydrodynamic cavitation reactor to determine if commercial sterility can be achieved at reduced processing temperatures. Sporicidal properties of the process were also tested on a low-acid (pH < 4.6) fluid food. Fluid foods were pumped under pressure into a hydrodynamic cavitation reactor and subjected to 2 rotor speeds and flow rates to achieve 2 designated exit temperatures. Thermal inactivation kinetics were used to determine heat-induced lethality for all organisms. Calcium-fortified apple juice processed at 3000 and 3600 rpm rotor speeds on the reactor went through a transient temperature change from 20 to 65.6 or 76.7 °C and the total process lethality exceeded 5-log reduction of Lactobacillus plantarum and Lactobacillus sakei cells, and Zygosaccharomyces bailii cells and ascospores. Tomato juice inoculated with Bacillus coagulans spores and processed at 3000 and 3600 rpm rotor speeds endured a transient temperature from 37.8 to 93.3 or 104.4 °C with viable CFU reductions of 0.88 and 3.10 log cycles, respectively. Skim milk inoculated with Clostridium sporogenes putrefactive anaerobe 3679 spores and processed at 3000 or 3600 rpm rotor speeds endured a transient temperature from 48.9 to 104.4 or 115.6 °C with CFU reductions of 0.69 and 2.84 log cycles, respectively. Utilizing hydrodynamic cavitation to obtain minimally processed pasteurized low-acid and commercially sterilized high-acid fluid foods is possible with appropriate process considerations for different products. [source]


Study on the reaction of methyl N -Methyl- N -(6-substituted-5-nitropyrimidin-4-yl)glycinates with sodium alkoxides

JOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 2 2006
Inga Susvilo
Methyl N -methyl- N -(6-substituted-5-nitropyrimidin-4-yl)glycinates (4a-n), obtained from 6-substituted-4-chloro-5-nitropyrimidines and sarcosine methyl ester (methyl 2-(methylamino)acetate), in the reaction with sodium alkoxides underwent transformations to give different products. N -methyl- N -(5-nitropyrimidin-4-yl)glycinates (4a,i,j) bearing amino and arylamino groups in the position 6 of the pyrimidine ring gave corresponding 6-substituted-4-methylamino-5-nitrosopyrimidines (5a,i,j). In the reaction of N -(6-alkylamino-5-nitropyrimidin-4-yl)- N -methylglycinates (4b,f-h) with sodium alkoxides the corresponding 6-alkylamino-4-methylamino-5-nitrosopyrimidines (5b,f-h) and 5-hydroxy-8-methyl-5,8-dihydropteridine-6,7-diones (6b,f-h) were formed. The main products of the reaction of N -(6-dialkylamino-5-nitropyrimidin-4-yl)- N -methylglycinates (4c-e,k,l), after work-up, were the corresponding 6-dialkylamino-9-methylpurin-8-ones (7c-e,k,l) and 8-alkoxy-6-dialkylamino-9-methylpurines (9c,1,10c,l). Methyl N -methyl- N -{[6-(2-methoxy-oxoethyl)thio]-5-nitropyrimidin-4-yl}glycinate (4n) under the same conditions gave methyl 7-methylaminothiazolo[5,4- d]pyrimidine-2-carboxylate (13). Mechanisms of the observed transformations are discussed. [source]


Environmental Impacts of Consumption in the European Union:High-Resolution Input-Output Tables with Detailed Environmental Extensions

JOURNAL OF INDUSTRIAL ECOLOGY, Issue 3 2006
Gjalt Huppes
Summary For developing product policy, insight into the environmental effects of products is required. But available life-cycle assessment studies (LCAs) are hardly comparable between different products and do not cover total consumption. Input-output analysis with environmental extensions (EEIOA) of full consumption is not available for the European Union. Available country studies have a low sector resolution and a limited number of environmental extensions. This study fills the gap between detailed LCA and low-resolution EEIOA, specifying the environmental effects of household consumption in the European Union, discerning nearly 500 sectors, while specifying a large number of environmental extensions. Added to the production sectors are a number of consumption activities with direct emissions, such as automobile driving, cooking and heating, and a number of postconsumer waste management sectors. The data for Europe have been constructed by using the sparse available and coarse economic and environmental data on European countries and adding technological detail mainly based on data from the United States. A small number of products score high on environmental impact per Euro and also have a substantial share of overall consumer expenditure. Several meat and dairy products, household heating, and car driving thus have a large share of the total environmental impact. Due to their sales volume, however, products with a medium or low environmental score per Euro may also have a substantial impact. This is the case with bars and restaurants, clothing, residential construction, and even a service such as telecommunications. The limitations in real European data made heroic assumptions necessary to operationalize the model. One conclusion, therefore, is that provision of data in Europe urgently needs to be improved, at least to the level of sector detail currently available for the United States and Japan. [source]


Reactions of 1,2,5-thiadiazole 1,1-dioxide derivatives with nitrogenated nucleophiles.

JOURNAL OF PHYSICAL ORGANIC CHEMISTRY, Issue 4 2003
1-dioxide, 4-diphenyl-, 5-thiadiazole , Addition of amines, Part , amides to
Abstract The addition reactions of some amides and aromatic amines to a CN double bond of 3,4-diphenyl-1,2,5-thiadiazole 1,1-dioxide (1) were studied in aprotic solvent solutions [N,N -dimethylformamide (DMF) and acetonitrile (MeCN)]. Equilibrium constants for the reactions of 1 with acetamide, 2-fluoroacetamide, butyramide, benzamide, aniline and 3-aminopyridine were measured using a previously reported cyclic voltammetric (CV) method. Aliphatic amines gave unstable solutions, probably owing to reactions of anionic species derived from 1. Other N nucleophiles tested (formamide, succinimide, thioacetamide and cyanamide) yielded different products that have not yet been characterized. DMF, N,N -dimethylacetamide (DMA) and N -methylacetamide did not react. The addition thiadiazoline produced in the reaction of acetamide with 1 was characterized by IR and 1H and 13C RMN NMR spectroscopy as a prototype compound. For this system, the equilibrium constant could also be measured by a standard UV,VIS method and was found to be in agreement with the value obtained by CV. The reaction of 1 with urea produced a bicyclic product, identified as 3a,6a-diphenyltetrahydroimidazo[4,5- c]-1,2,5-thiadiazol-5-one 2,2-dioxide. Copyright © 2003 John Wiley & Sons, Ltd. [source]


Comparison of iron chelates and complexes supplied as foliar sprays and in nutrient solution to correct iron chlorosis of soybean

JOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 1 2010
Patricia Rodríguez-Lucena
Abstract The application of synthetic chelates is the most efficient remedy for correcting iron (Fe) chlorosis. However, chelates are usually expensive and nondegradable products. Recently, new degradable chelates have been proposed for their use as Fe fertilizers. Also, Fe complexes cheaper than synthetic chelates and derived from natural products are also used to correct Fe deficiencies. Fifteen products, including five different synthetic chelates (Fe-EDDS, Fe-IDHA, and three Fe-EDTA formulations) and ten natural complexes (humates, lignosulfonates, amino acids, glycoproteins, polyamines, citrate, and gluconate), have been compared when applied at low concentration to soybean (Glycine max L.) chlorotic plants grown in hydroponics under controlled conditions. In the first experiment, Fe compounds were applied to the nutrient solution, while in the second trial, Fe was foliar-supplied. Dry matter, Fe concentration in shoots and roots, and SPAD values were used to evaluate the effectiveness of the Fe in the different products. In the nutrient-solution experiment, synthetic chelates provided better plant growth, Fe concentration, and SPAD values than complexes. Among the Fe complexes, transferrin generally provided good plant responses, similar to those obtained with synthetic chelates. After foliar application, the highest regreening was observed for plants treated with synthetic chelates and amino acid complexes, but the translocation to roots only occurred for Fe lignosulfonate. Fe-EDDS and Fe-EDTA performed in a similar way when applied in nutrient solution or as foliar sprays. [source]


Corrosion of Dental Magnet Attachments for Removable Prostheses on Teeth and Implants

JOURNAL OF PROSTHODONTICS, Issue 4 2009
Arne F. Boeckler DMD, Dr Med Dent
Abstract Purpose: For a long time, the use of magnets for the anchorage of dental prostheses failed due to lack of biocompatibility and the magnets' high susceptibility to corrosion in the mouth. These facts make encapsulation of the magnetic alloy with a corrosion-resistant, tight, and functionally firm sealing necessary. Due to different products and analysis methods, it is not feasible to compare the findings for contemporary products with the sparse and rather old test results in the literature. Therefore, the aim of this study was the standardized control and the comparison of the corrosion behavior of modern magnetic attachments for use on teeth and dental implants. Materials and Methods: Thirty-seven components of magnetic attachments on implants and natural teeth from different alloys (NdFeB, SmCo, Ti, CrMoMnTiFe, etc.) as delivered by the manufacturers or fabricated according to their instructions were examined for their corrosion behavior using the statical immersion analysis (ISO 10271:2001). Four specimens of every product with the same design were used. An uncased SmCo magnet served as control. Analyses after 1, 4, 7, and 28 days of the storage in corrosion solution were made. The eluate was examined quantitatively on the alloy components of the respective component with the help of optical emission spectrometry (,g/cm2). The results were compared to the requirements of ISO standard 22674:2006. In addition, existing corrosion products were also defined in the solution after 28 days. The results were analyzed descriptively and statistically to determine possible significant differences (t -test and Mann-Whitney-Wilcoxon rank-sums test; p < 0.05). Results: Dissolved metal ions could be found on all tested products. The release after 1 and 4 days was different for all specimens. In the group of implant abutments, the highest ion release after 7 days was found (all measurements ,g/cm2): Fe (13.94, Magfit-IP-IDN dome type), Pd (1.53, Medical-anchor), Cr (1.32, Magfit-IP-IDN dome type), Ti (1.09, Magfit-IP-IDN abutment), Co (0.81, Medical-anchor), and B (0.6, Magfit-IP-IDN dome type). After 28 days, the analyzed ion release increased irregularly: Fe (173.58, Magfit-IP-IDN dome type), Pd (44.17, Medical-anchor), Cr (2.02, Magfit-IP-IDN dome type), Ti (2.11, Magfit-IP-IDN abutment), Co (26.13, Medical-anchor), B (1.77, Magfit-IP-IDN dome type), and Nd (79.18, Magfit-IP-IDN dome type). In the group of magnetic systems on natural teeth, the highest ion release after 7 days was found for Fe (4.81, Magfit DX 800 keeper), Cr (1.18, Magfit DX 800 keeper), Pd (0.21, Direct System Keeper), Ni (0.18, WR-Magnet S3 small), Co (0.12, Direct System Keeper), and Ti (0.09, Magna Cap , Mini). After 28 days, the analyzed ion release increased non-uniformly: Fe (31.92, Magfit DX 800 Keeper), Cr (6.65, Magfit DX 800 Keeper), Pd (18.19, Direct System Keeper), Ni (0.61, WR-Magnet S3 small), Co (10.94, Direct System Keeper), Ti (0.83, Magna Cap , Mini), and Pd (2.78, EFM Alloy). In contrast, the uncased control magnet showed an exponential release after 7 days of Sm ions (55.06) and Co-ions (86.83), after 28 days of Sm ions (603.91) and Co ions (950.56). The release of corrosion products of all tested products stayed significantly under the limit of 200 ,g/cm2 (ISO 22674:2006). In contrast, the non-encapsulated control magnet exceeded that limit significantly. Conclusion: The analysis of the corrosion behavior of modern magnetic attachments for use on teeth and dental implants according to ISO 10271:2001 showed that metal ions had dissolved on all specimens. In the case of one product, the magnet corroded. For this product, an improvement of the capsulation would be desirable. None of the products reached the limit specified in ISO 22674:2006. All products seem to be suitable for dental application. Further studies in regard to the specific biocompatibility and possible cytotoxic effects on mucosa and tissue would be desirable. [source]


THE ANALYSIS OF STRESS RELAXATION DATA OF SOME VISCOELASTIC FOODS USING A TEXTURE ANALYZER,

JOURNAL OF TEXTURE STUDIES, Issue 4 2006
H. SINGH
ABSTRACT Uniaxial compression test for dough and several commercial products like jello, mozzarella cheese, cheddar cheese, tofu and sausage (cooked and uncooked) was performed using a texture analyzer (TA). Percent stress relaxation (%SR ), k1 (initial rate of relaxation), k2 (extent of relaxation) and relaxation time (RT) were calculated and compared for different products. The TA software was used to convert the raw SR data into a linear form. Constants k1 and k2 were determined from the intercept and slope of the linear data. Higher values of %SR and k2 (90 and 9, respectively) indicated higher elasticity for jello, whereas wheat flour dough samples showed the lowest values (20,30) for %SR and 1 to 2 for k2. The RT and k1 values were not good indicators for differentiating different products based on their viscoelastic behavior. Measurement of RT was limited by the maximum time for which the data were collected, whereas k1, because of its mathematical form, needed careful interpretation. In this study, %SR was found to be a good measure to interpret viscoelasticity of different food samples. [source]


RELATIVE IMPORTANCE OF COHESION AND ADHESION FOR SENSORY STICKINESS OF SEMISOLID FOODS

JOURNAL OF TEXTURE STUDIES, Issue 6 2004
B. DUNNEWIND
ABSTRACT Sensory stickiness (sticky mouthfeel) was hypothesized to result from the viscoelastic and adhesive properties of a foodstuff. The objective of the present study was to investigate the relative importance of these two properties. Measurements consisted of compression , decompression cycles on a texture analyzer, with product, type of surface, the presence or absence of saliva and compression regime as variables. Products included commercial mayonnaises, custard desserts and warm sauces, varying in apparent viscosity (at shear rate of 10 s,1) between 0.3 and 18.3 Pa.s. Fairly good models were obtained, predicting sensory stickiness with R2 = 0.85,0.92. The predictive value of the mathematical models did not increase when the surface characteristics approached those of the human tongue (use of porcine lingual mucosa). Different surfaces or the use of saliva resulted in differences in the absolute values of the parameters, but their relative values when comparing different products did not change. The parameters appearing in the predictive models represented product characteristics only. The type of surface was not an important factor in determining differences in sensory stickiness between these samples. For the products used in this study, adhesion was large enough to prevent detachment of the sample from the surfaces, i.e., adhesion was not limiting. Variations in perceived stickiness could be explained with R2 = 0.86, based on only two product characteristics: consistency and ,long behavior' (the extent to which necking occurs during decompression). This was better than the correlation between sensory stickiness and apparent viscosity (R2 = 0.77),, confirming, the relevance of ,long behavior' for sensory stickiness. [source]


Small price changes and menu costs

MANAGERIAL AND DECISION ECONOMICS, Issue 7 2007
Saul Lach
We find that while some individual price changes are indeed ,small', the average price change of different products within a store in any given month is not. Moreover, the smaller the price change of an individual product, the larger the average price change of the remaining products sold by the store. We argue that these findings are consistent with extensions of menu cost models of price-setting behavior to multiproduct firms when these firms have high average costs and low marginal costs of changing prices. Copyright © 2007 John Wiley & Sons, Ltd. [source]


Joint Production with ,Restricted Free Disposal'

METROECONOMICA, Issue 1 2001
Christian Lager
A single production system with constant returns can produce any level and composition of demand by appropriate intensities of the cost-minimizing processes. Hence, in the long run, products can never be in excess supply and there exists a system of prices of production which is semipositive and independent of demand. These (and other) properties do not, in general, carry over to joint production systems where one or several processes produce two or more different products. The proportions in which products emerge will generally be different from those in which they are required for use. The usual approach to that problem is to apply the rule of ,free goods'. This assumption may be applied to goods which, if they are left where they are and as they are, cause neither costs nor benefits. But it cannot be applied to outworn machines, scrap, wastes or pollutants and is therefore not generally applicable. The present paper aims at finding conditions for the existence of cost-minimizing systems for cases where this crucial assumption either is completely absent or is substituted by the assumption of ,restricted free disposal', i.e. by the assumption that excess production is permitted up to a certain tolerated limit. It will be proved that the conditions for the existence of cost-minimizing systems with free disposal carry over to systems with restricted free disposal. [source]


EU Forum: The CREATE Project: development of certified reference materials for allergenic products and validation of methods for their quantification

ALLERGY, Issue 3 2008
R. Van Ree
Allergen extracts have been used for diagnosis and treatment of allergy for around 100 years. During the second half of 20th century, the notion increasingly gained foothold that accurate standardization of such extracts is of great importance for improvement of their quality. As a consequence, manufacturers have implemented extensive protocols for standardization and quality control. These protocols have overall IgE-binding potencies as their focus. Unfortunately, each company is using their own in-house reference materials and their own unique units to express potencies. This does not facilitate comparison of different products. During the last decades, most major allergens of relevant allergen sources have been identified and it has been established that effective immunotherapy requires certain minimum quantities of these allergens to be present in the administered maintenance dose. Therefore, the idea developed to introduce major allergens measurements into standardization protocols. Such protocols based on mass units of major allergen, quantify the active ingredients of the treatment and will at the same time allow comparison of competitor products. In 2001, an EU funded project, the CREATE project, was started to support introduction of major allergen based standardization. The aim of the project was to evaluate the use of recombinant allergens as reference materials and of ELISA assays for major allergen measurements. This paper gives an overview of the achievements of the CREATE project. [source]


Managing platform architectures and manufacturing processes for nonassembled products

THE JOURNAL OF PRODUCT INNOVATION MANAGEMENT, Issue 4 2002
Marc H. Meyer
The article presents methods for defining product platforms and measuring business performance in process intensive industries. We first show how process intensive product platforms can be defined using the products and processes of a film manufacturer. We then present an empirical method for understanding the dynamics of process intensive platform innovation, allocating engineering and sales data to specific platform and product development efforts within a product family. We applied this method to a major product line of a materials manufacturer. We gathered ten years of engineering and manufacturing cost data and allocated these to successive platforms and products, and then generated R&D performance measures. These data show the dynamic of heavy capital spending relative to product engineering as one might expect in a process intensive industries. The data also show how derivative products can be leveraged from underlying product platforms and processes for nonassembled products. Embedded within these data are strategies for creating reusable subsystems (comprising components, materials, etc.) and common production processes. Hard data on the degree to which subsystems and processes are shared across different products frequently are typically not maintained by corporations for the duration needed to understand the dynamics of evolving product families. For this reason, we developed and applied a second method to assess the degree of reuse of subsystems and processes. This method asks engineering managers to provide subjective ratings on an ordinal scale regarding the use of technology and processes from one product to the next in a cumulative manner. We find that high levels of reuse generally indicate that a product family was developed with a platform discipline. We applied this measure of platform intensity to two product lines of integrated circuits from another large manufacturer. We used this method to gather approximately ten years of information for each product family. Upon analysis, one product family showed substantial platform discipline, emphasizing a common architecture and processes across specific products within the product line. The other product family was developed with significantly less sharing and reuse of architecture, components, and processes. We then found that the platform centric product family outperformed the latter along a number of performance dimensions over the course of the decade under examination. [source]


Comparison of best,worst and hedonic scaling for the measurement of consumer wine preferences

AUSTRALIAN JOURNAL OF GRAPE AND WINE RESEARCH, Issue 3 2009
S. MUELLER
Abstract Background and Aims:, Best,worst scaling (BWS) is compared to standard hedonic scaling for measuring consumer wine preferences. BWS is a relatively new method for producing ratio-level scales and has gained recent attention for application in sensory research, but has not been applied to wine. Methods and Results:, Regular wine consumers (112) evaluated eight designed wines with both scaling methods in an intra-subject design over two test periods. The methods did not result in comparable product liking results. The eight wines could almost be differentiated on an aggregated level with hedonic ratings (P = 0.076); there was no significant difference with BWS. Latent class analysis was used to identify two clusters, which differed on the preferences for the designed sensory components. The BWS design had to be split into several blocks, so no complete individual measures were available, which prevented analysing heterogeneity for this method. Conclusions:, BWS needs more wines to be assessed per person in order to discriminate between red wines and to allow modelling of consumer preference heterogeneity. Respondents would have to accomplish complete individual BWS designs, which requires repeated exposure to the same set of wines over several tasting sessions. Significance of the Study:, This study demonstrates that BWS is not as suitable for sensory consumer preference measurement of red wine as hedonic rating. While BWS has shown a higher discriminative ability for different products and in non-sensory research, the factors of alcohol, tannin and memory fatigue make it less practical for red wine sensory measurement compared to hedonic rating. [source]


Ultra scale-down approaches for clarification of mammalian cell culture broths in disc-stack centrifuges

BIOTECHNOLOGY PROGRESS, Issue 6 2009
Ferhana Zaman
Abstract Ultra-scale down (USD) methodology developed by University College London for cell broth clarification with industrial centrifuges was applied to two common cell lines (NS0 and GS-CHO) expressing various therapeutic monoclonal antibodies. A number of centrifuges at various scales were used with shear devices operating either by high speed rotation or flow-through narrow channels. The USD methodology was found effective in accounting for both gravitational and shear effects on clarification performance with three continuous centrifuges at pilot and manufacturing scales. Different shear responses were observed with the two different cell lines and even with the same cell line expressing different products. Separate particle size analysis of the treated broths seems consistent with the shear results. Filterability of the centrifuged solutions was also evaluated to assess the utility of the USD approach for this part of the clarification operation. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 [source]


Parental knowledge of topical therapies in the treatment of childhood atopic dermatitis

CLINICAL & EXPERIMENTAL DERMATOLOGY, Issue 5 2003
P. E. Beattie
Summary Poor adherence with therapy is a major cause of treatment failure in atopic dermatitis. Reasons given are multifactorial, and include fear of real or imaginary side-effects, under-prescribing, failure to renew prescriptions on time, lack of time, and child refusal of therapy. Most important, however, is lack of knowledge about treatment, in particular the use of topical corticosteroid (TCS) therapy. We conducted a questionnaire-based study to determine the level of use and knowledge of commonly prescribed TCS preparations amongst parents or carers of 100 children attending paediatric outpatient clinics. Weakly potent TCSs were the most commonly used (86%), but poorly understood. Only 35 (41%) who had used hydrocortisone were aware that it was weakly potent, and 44% graded it as moderately potent. Of 65 who had used the moderately potent TCS clobetasone butyrate 0.05% (Eumovate®; Glaxo Wellcome, Uxbridge, UK), 19 (29%) graded it as potent and eight (12%) as weak. Of 50 who had used betamethasone valerate 0.1% (Betnovate®; Glaxo Wellcome, Uxbridge, UK), 42% did not grade it as potent. Understanding of TCS/antimicrobial combinations was generally worse. The hydrocortisone 1%/fusidic acid 2% combination (Fucidin H®; Leo, Risborough, Bucks, UK) was graded as moderate or strong by 88% of the 74 who had used it. Over half (53%) of the 34 using the combination of clobetasone butyrate 0.05%/nystatin 100 000 i.u./g tetracycline 3% (Trimovate®; Glaxo Wellcome, Uxbridge, UK) assumed that it was a potent TCS. Forty-nine had used Fucibet® (betamethasone valerate 0.1%, fusidic acid 2%; Leo, Risborough, Bucks, UK) but 34.5% did not grade it as potent. There was poor knowledge of the strengths of some of the most commonly used TCSs, and all steroid/antimicrobial combinations were perceived as being of greater potency than the constituent steroid alone. Fusidic acid was thought to be a steroid by almost half (46.9%) of the respondents. The packaging of the different products by some pharmaceutical companies is remarkably similar and labelling contains information on the compound and percentage rather than potency of the TCS. This may be a source of confusion. We recommend that manufacturers clearly label TCS products by potency as mild, moderate, potent or very potent and that packaging is sufficiently different for each strength of TCS or emollient to avoid confusion. In order to achieve optimal topical treatment for atopic dermatitis, patients and their carers must receive adequate information and training in how and when to use topical therapies in conjunction with written care plans. [source]