WorldWideScience

Sample records for admixtures

  1. Low Temperature Concrete Admixture

    OpenAIRE

    ECT Team, Purdue

    2007-01-01

    Performing construction processes under the cold weather condition requires construction engineers to plan operations considering low temperature condition. Concrete admixture mostly chemically interact with the constituents of concrete and affect the properties and characteristics of the fresh and hardened concrete and its durability. The purposes of the admixtures include water reduction, high strength, corrosion protection, crack control, finish enhancement, flowability, etc. One of the in...

  2. Admixture elements as indicators of fluorite genesis

    International Nuclear Information System (INIS)

    Present book is devoted to comparative analysis of abundance and distribution of admixture elements in fluorite-mineral. The data on composition and content of admixture elements in fluorite was generalized. The hydrothermal deposits were characterized on mineral types.

  3. Prospects for Admixture Mapping of Complex Traits

    OpenAIRE

    McKeigue, Paul M

    2004-01-01

    Admixture mapping extends to human populations the principles that underlie linkage analysis of an experimental cross. For detecting genes that contribute to ethnic variation in disease risk, admixture mapping has greater statistical power than family-linkage studies. In comparison with association studies, admixture mapping requires far fewer markers to search the genome and is less affected by allelic heterogeneity. Statistical-analysis programs for admixture mapping are now available, and ...

  4. Shrinkage Reducing Admixture for Concrete

    OpenAIRE

    ECT Team, Purdue

    2007-01-01

    Concrete shrinkage cracking is a common problem in all types of concrete structures, especially for structures and environments where the cracks are prevalent and the repercussions are most severe. A liquid shrinkage reducing admixture for concrete, developed by GRACE Construction Products and ARCO Chemical Company, that reduces significantly the shrinkage during concrete drying and potentially reduces overall cracking over time.

  5. Ancient Admixture in Human History

    Science.gov (United States)

    Patterson, Nick; Moorjani, Priya; Luo, Yontao; Mallick, Swapan; Rohland, Nadin; Zhan, Yiping; Genschoreck, Teri; Webster, Teresa; Reich, David

    2012-01-01

    Population mixture is an important process in biology. We present a suite of methods for learning about population mixtures, implemented in a software package called ADMIXTOOLS, that support formal tests for whether mixture occurred and make it possible to infer proportions and dates of mixture. We also describe the development of a new single nucleotide polymorphism (SNP) array consisting of 629,433 sites with clearly documented ascertainment that was specifically designed for population genetic analyses and that we genotyped in 934 individuals from 53 diverse populations. To illustrate the methods, we give a number of examples that provide new insights about the history of human admixture. The most striking finding is a clear signal of admixture into northern Europe, with one ancestral population related to present-day Basques and Sardinians and the other related to present-day populations of northeast Asia and the Americas. This likely reflects a history of admixture between Neolithic migrants and the indigenous Mesolithic population of Europe, consistent with recent analyses of ancient bones from Sweden and the sequencing of the genome of the Tyrolean “Iceman.” PMID:22960212

  6. Early hydration cement Effect of admixtures superplasticizers

    Directory of Open Access Journals (Sweden)

    Puertas, F.

    2001-06-01

    Full Text Available Early hydration of portland cement with superplasticizer admixtures of different nature has been studied. These admixtures were: one based on melamine synthetic, other based on vinyl copolymer and other based on polyacrylate copolymers. The dosage of the formers were constant (1% weigth of cement and for the third, the influence of admixture dosage was also evaluated, giving dosage values among 1-0.3%. The pastes obtained were studied by conduction calorimetry, XRD and FTIR. Also the apparent fluidity was determined by "Minislump" test. The main results obtained were: a superplasticizers admixtures used, regardless of their nature and for the polycarboxilate one the dosage, retard the silicate hydration (specially, alite phase, b The ettringite formation is affected by the nature of the admixture. cA relationship between the dosage of admixture based on polycarboxilates and the time at the acceleration has been established. A lineal relation (y = 11.03 + 16.05x was obtained. From these results is possible to know, in function of dosage admixture, the time when the masive hydration products and the setting times are produced. Also the total heat releases in these reactions is independent of the nature and dosage of admixture, saying that in all cases the reactions are the same.

    En el presente trabajo se ha estudiado la hidratación inicial de un cemento portland aditivado con superplastificantes de diferente naturaleza. Dichos aditivos fueron: uno basado en melaminas sintéticas, otro en copolímeros vinilicos y otro en policarboxilatos. La dosificación de los dos primeros se fijó constante en 1% en peso con relación al cemento, mientras que para el tercero se evaluó, también, la influencia de la dosificación, tomando proporciones desde el 1% hasta el 0,3%. Las pastas obtenidas se estudiaron por: calorimetría de conducción, DRX y FTIR. También se determinó la fluidez de la pasta a través del ensayo del "Minislump ". Los

  7. Admixture as the basis for genetic mapping

    OpenAIRE

    Buerkle, C. Alex; Lexer, Christian

    2008-01-01

    Genetic mapping in natural populations is increasing rapidly in feasibility and accessibility. As with many areas in genetics, advances in molecular techniques and statistics are drastically altering how we can investigate inheritance in wild organisms. For ecology and evolution, this is particularly significant and promising, because many of the organisms of interest are not amenable to conventional genetic approaches. Admixture mapping falls within a family of statistical approaches that us...

  8. Rapid-1 Hardening Accelerator Concrete Admixture

    OpenAIRE

    ECT Team, Purdue

    2007-01-01

    SIKA Rapid-1 is a concrete admixture that allows the development of very early high strengths in concrete consisting of commonly used mix components. Unlike concrete set accelerators, it does not reduce set time or long-term strength, and it does not corrode steel reinforcing. This hardening accelerator allows placement of fresh concrete without early stiffening, followed by a period of very rapid strength gain after initial set.

  9. Elements-admixtures of fluorite. Research technique

    International Nuclear Information System (INIS)

    Present article is devoted to elements-admixtures of fluorite and research techniques used. As a material for researches the mono mineral samples of fluorite of various geologic deposits and ores were used. The determination of sodium and potassium was conducted by means of flame photometry. Strontium, uranium, thorium, lead and rubidium were determined by means of quantitative X-ray spectroscopic analysis. The barium analysis was conducted by means of quantitative method. The manganese analysis was conducted by means of electron paramagnetic resonance.

  10. Admixture, Population Structure, and F-Statistics.

    Science.gov (United States)

    Peter, Benjamin M

    2016-04-01

    Many questions about human genetic history can be addressed by examining the patterns of shared genetic variation between sets of populations. A useful methodological framework for this purpose isF-statistics that measure shared genetic drift between sets of two, three, and four populations and can be used to test simple and complex hypotheses about admixture between populations. This article provides context from phylogenetic and population genetic theory. I review howF-statistics can be interpreted as branch lengths or paths and derive new interpretations, using coalescent theory. I further show that the admixture tests can be interpreted as testing general properties of phylogenies, allowing extension of some ideas applications to arbitrary phylogenetic trees. The new results are used to investigate the behavior of the statistics under different models of population structure and show how population substructure complicates inference. The results lead to simplified estimators in many cases, and I recommend to replaceF3with the average number of pairwise differences for estimating population divergence. PMID:26857625

  11. High-Performance Grouting Mortar Based on Mineral Admixtures

    OpenAIRE

    2015-01-01

    A study on high-performance grouting mortar is reported. The common mortar was modified by mineral admixtures such as gypsum, bauxite, and alunite. The effects of mineral admixtures on the fluidity, setting time, expansion, strength, and other properties of mortar were evaluated experimentally. The microstructure of the modified mortar was characterized by X-ray diffraction, scanning electron microscopy, and mercury intrusion porosimetry. Moreover, the expansive performance and strength of th...

  12. Geographic patterns of genome admixture in Latin American Mestizos.

    Directory of Open Access Journals (Sweden)

    Sijia Wang

    2008-03-01

    Full Text Available The large and diverse population of Latin America is potentially a powerful resource for elucidating the genetic basis of complex traits through admixture mapping. However, no genome-wide characterization of admixture across Latin America has yet been attempted. Here, we report an analysis of admixture in thirteen Mestizo populations (i.e. in regions of mainly European and Native settlement from seven countries in Latin America based on data for 678 autosomal and 29 X-chromosome microsatellites. We found extensive variation in Native American and European ancestry (and generally low levels of African ancestry among populations and individuals, and evidence that admixture across Latin America has often involved predominantly European men and both Native and African women. An admixture analysis allowing for Native American population subdivision revealed a differentiation of the Native American ancestry amongst Mestizos. This observation is consistent with the genetic structure of pre-Columbian populations and with admixture having involved Natives from the area where the Mestizo examined are located. Our findings agree with available information on the demographic history of Latin America and have a number of implications for the design of association studies in population from the region.

  13. Learning with Admixture: Modeling, Optimization, and Applications in Population Genetics

    DEFF Research Database (Denmark)

    Cheng, Jade Yu

    2016-01-01

    including population splits, effective population sizes, gene flow, etc. Since joining the CoalHMM development team in 2014, I have mainly contributed in two directions: 1) improving optimizations through heuristic-based evolutionary algorithms and 2) modeling of historical admixture events. Ohana, meaning...... data. Ohana's admixture module is based on classical structure modeling but uses new optimization subroutines through quadratic programming, which outperform the current state-of-the-art software in both speed and accuracy. Ohana presents a new method for phylogenetic tree inference using Gaussian...

  14. Research and manufacture about high-activity small admixture in sprayed concrete

    Energy Technology Data Exchange (ETDEWEB)

    Fan, W.; Zhang, Z.; Zheng, Y. [Jiaozuo Institute of Technology, Jiaozuo (China)

    2000-04-01

    Two types of high-activity small admixture are researched and produced by using industrial wastes: (1) F-type high-activity small admixture; (2) K-type high-activity small admixture. If these high-activity small admixtures were used to replace 30 percent of cement, the strength of the sprayed concrete may be enhanced by about 20 percent. 1 ref., 7 tabs.

  15. North African populations carry the signature of admixture with Neandertals

    DEFF Research Database (Denmark)

    Sánchez-Quinto, Federico; Botigué, Laura R; Civit, Sergi;

    2012-01-01

    One of the main findings derived from the analysis of the Neandertal genome was the evidence for admixture between Neandertals and non-African modern humans. An alternative scenario is that the ancestral population of non-Africans was closer to Neandertals than to Africans because of ancient popu...

  16. A Spatial Framework for Understanding Population Structure and Admixture

    Science.gov (United States)

    Bradburd, Gideon S.; Ralph, Peter L.; Coop, Graham M.

    2016-01-01

    Geographic patterns of genetic variation within modern populations, produced by complex histories of migration, can be difficult to infer and visually summarize. A general consequence of geographically limited dispersal is that samples from nearby locations tend to be more closely related than samples from distant locations, and so genetic covariance often recapitulates geographic proximity. We use genome-wide polymorphism data to build “geogenetic maps,” which, when applied to stationary populations, produces a map of the geographic positions of the populations, but with distances distorted to reflect historical rates of gene flow. In the underlying model, allele frequency covariance is a decreasing function of geogenetic distance, and nonlocal gene flow such as admixture can be identified as anomalously strong covariance over long distances. This admixture is explicitly co-estimated and depicted as arrows, from the source of admixture to the recipient, on the geogenetic map. We demonstrate the utility of this method on a circum-Tibetan sampling of the greenish warbler (Phylloscopus trochiloides), in which we find evidence for gene flow between the adjacent, terminal populations of the ring species. We also analyze a global sampling of human populations, for which we largely recover the geography of the sampling, with support for significant histories of admixture in many samples. This new tool for understanding and visualizing patterns of population structure is implemented in a Bayesian framework in the program SpaceMix. PMID:26771578

  17. Venous admixture in COPD: Pathophysiology and therapeutic approaches

    OpenAIRE

    Cooper, CB; Celli, B

    2008-01-01

    Chronic obstructive and interstitial lung diseases impair pulmonary gas exchange leading to wasted ventilation (alveolar dead space) and wasted perfusion (venous admixture). These two fundamental types of abnormality represent opposite ends of the spectrum of ventilation-perfusion mismatch with V̇/Q̇ ratios of infinity and zero. Treatment approaches that improve airway function, reduce air trapping and hyperinflation have received much attention and might be successful at ameliorating the pro...

  18. Extensive Admixture and Selective Pressure Across the Sahel Belt

    Czech Academy of Sciences Publication Activity Database

    Triska, P.; Soares, P.; Patin, E.; Fernandes, V.; Černý, Viktor; Pereira, L.

    2015-01-01

    Roč. 7, č. 12 (2015), s. 3484-3495. ISSN 1759-6653 R&D Projects: GA ČR GA13-37998S Institutional support: RVO:67985912 Keywords : genome-wide diversity * admixture * selection * Sahel Subject RIV: AC - Archeology, Anthropology, Ethnology Impact factor: 4.229, year: 2014 http://gbe.oxfordjournals.org/content/7/12/3484.full.pdf+html

  19. Mirror matter admixtures in K_L to mu^+ mu^-

    CERN Document Server

    Sánchez-Colón, G; Sanchez-Colon, Gabriel; Garcia, Augusto

    2006-01-01

    Our previous analysis on the contributions of mirror matter admixtures in ordinary hadrons to K_L to gamma gamma is extended to study the relevance of such contributions to the K_L to mu^+ mu^- rare decay. The mixing angle of the admixtures previously determined to describe the enhancement phenomenon in two body non-leptonic decays of strange hadrons is used, along with recent results for the description of the strong and electromagnetic interaction parts of the transition amplitudes. We find that these admixtures give a significant contribution with a small SU(3) breaking of only 2.8%, we also find a value of \\sim -17.9^{\\circ} for the eta-eta' mixing angle consistent with some of its determinations in the literature and a preferred negative value around -16 for the local counter-term contribution chi_1 + chi_2 consistent with the existence of a unique counter-term assuming lepton universality. We conclude that those mixings may be relevant in low energy physics and should not be ignored.

  20. Admixture mapping identifies introgressed genomic regions in North American canids.

    Science.gov (United States)

    vonHoldt, Bridgett M; Kays, Roland; Pollinger, John P; Wayne, Robert K

    2016-06-01

    Hybrid zones typically contain novel gene combinations that can be tested by natural selection in a unique genetic context. Parental haplotypes that increase fitness can introgress beyond the hybrid zone, into the range of parental species. We used the Affymetrix canine SNP genotyping array to identify genomic regions tagged by multiple ancestry informative markers that are more frequent in an admixed population than expected. We surveyed a hybrid zone formed in the last 100 years as coyotes expanded their range into eastern North America. Concomitant with expansion, coyotes hybridized with wolves and some populations became more wolflike, such that coyotes in the northeast have the largest body size of any coyote population. Using a set of 3102 ancestry informative markers, we identified 60 differentially introgressed regions in 44 canines across this admixture zone. These regions are characterized by an excess of exogenous ancestry and, in northeastern coyotes, are enriched for genes affecting body size and skeletal proportions. Further, introgressed wolf-derived alleles have penetrated into Southern US coyote populations. Because no wolves currently exist in this area, these alleles are unlikely to have originated from recent hybridization. Instead, they probably originated from intraspecific gene flow or ancient admixture. We show that grey wolf and coyote admixture has far-reaching effects and, in addition to phenotypically transforming admixed populations, allows for the differential movement of alleles from different parental species to be tested in new genomic backgrounds. PMID:27106273

  1. Recent admixture in an Indian population of African ancestry.

    Science.gov (United States)

    Narang, Ankita; Jha, Pankaj; Rawat, Vimal; Mukhopadhyay, Arijit; Mukhopadhayay, Arijit; Dash, Debasis; Basu, Analabha; Mukerji, Mitali

    2011-07-15

    Identification and study of genetic variation in recently admixed populations not only provides insight into historical population events but also is a powerful approach for mapping disease loci. We studied a population (OG-W-IP) that is of African-Indian origin and has resided in the western part of India for 500 years; members of this population are believed to be descendants of the Bantu-speaking population of Africa. We have carried out this study by using a set of 18,534 autosomal markers common between Indian, CEPH-HGDP, and HapMap populations. Principal-components analysis clearly revealed that the African-Indian population derives its ancestry from Bantu-speaking west-African as well as Indo-European-speaking north and northwest Indian population(s). STRUCTURE and ADMIXTURE analyses show that, overall, the OG-W-IPs derive 58.7% of their genomic ancestry from their African past and have very little inter-individual ancestry variation (8.4%). The extent of linkage disequilibrium also reveals that the admixture event has been recent. Functional annotation of genes encompassing the ancestry-informative markers that are closer in allele frequency to the Indian ancestral population revealed significant enrichment of biological processes, such as ion-channel activity, and cadherins. We briefly examine the implications of determining the genetic diversity of this population, which could provide opportunities for studies involving admixture mapping. PMID:21737057

  2. High-Performance Grouting Mortar Based on Mineral Admixtures

    Directory of Open Access Journals (Sweden)

    Cong Ma

    2015-01-01

    Full Text Available A study on high-performance grouting mortar is reported. The common mortar was modified by mineral admixtures such as gypsum, bauxite, and alunite. The effects of mineral admixtures on the fluidity, setting time, expansion, strength, and other properties of mortar were evaluated experimentally. The microstructure of the modified mortar was characterized by X-ray diffraction, scanning electron microscopy, and mercury intrusion porosimetry. Moreover, the expansive performance and strength of the grouting mortar were verified by anchor pullout test. The results show that the best conditions for gypsum-bauxite grouting mortar are as follows: a water-to-binder ratio of 0.3, a mineral admixture content of ~15%, and a molar ratio K of 2. The ultimate bearing capacity of the gypsum-bauxite grouting mortar anchor increased by 39.6% compared to the common mortar anchor. The gypsum-bauxite grouting mortar has good fluidity, quick-setting, microexpansion, early strength, and high strength performances.

  3. Measuring and using admixture to study the genetics of complex diseases

    Directory of Open Access Journals (Sweden)

    Halder Indrani

    2003-11-01

    Full Text Available Abstract Admixture is an important evolutionary force that can and should be used in efforts to apply genomic data and technology to the study of complex disease genetics. Admixture linkage disequilibrium (ALD is created by the process of admixture and, in recently admixed populations, extends for substantial distances (of the order of 10 to 20 cM. The amount of ALD generated depends on the level of admixture, ancestry information content of markers and the admixture dynamics of the population, and thus influences admixture mapping (AM. The authors discuss different models of admixture and how these can have an impact on the success of AM studies. Selection of markers is important, since markers informative for parental population ancestry are required and these are uncommon. Rarely does the process of admixture result in a population that is uniform for individual admixture levels, but instead there is substantial population stratification. This stratification can be understood as variation in individual admixtures and can be both a source of statistical power for ancestry-phenotype correlation studies as well as a confounder in causing false-positives in gene association studies. Methods to detect and control for stratification in case/control and AM studies are reviewed, along with recent studies showing individual ancestry-phenotype correlations. Using skin pigmentation as a model phenotype, implications of AM in complex disease gene mapping studies are discussed. Finally, the article discusses some limitations of this approach that should be considered when designing an effective AM study.

  4. Practical handling of AIO admixtures – Guidelines on Parenteral Nutrition, Chapter 10

    OpenAIRE

    Stanga, Z; Franken, C.; Mühlebach, S; Working group for developing the guidelines for parenteral nutrition of The German Association for Nutritional Medicine

    2009-01-01

    All-in-one admixtures (AIO-admixtures) provide safe, effective and low-risk PN (parenteral nutrition) for practically all indications and applications. Water, energy (carbohydrates and lipids), amino acids, vitamins and trace elements are infused together with PN either as industrially-manufactured AIO admixtures provided as two- or three-chamber bags (shelf life usually more than 12 months) completed with electrolytes and micronutrients where appropriate or as individually compounded ready-t...

  5. Practical handling of AIO admixtures - Guidelines on Parenteral Nutrition, Chapter 10

    OpenAIRE

    Mühlebach, S; Franken, C.; Stanga, Z; Working group for developing the guidelines for parenteral nutrition of The German Association for Nutritional Medicine

    2009-01-01

    All-in-one admixtures (AIO-admixtures) provide safe, effective and low-risk PN (parenteral nutrition) for practically all indications and applications. Water, energy (carbohydrates and lipids), amino acids, vitamins and trace elements are infused together with PN either as industrially-manufactured AIO admixtures provided as two- or three-chamber bags (shelf life usually more than 12 months) completed with electrolytes and micronutrients where appropriate or as individually compounded ready-t...

  6. Polycarboxylate superplasticiser admixtures: effect on hydration, microstructure and rheological behaviour in cement pastes

    OpenAIRE

    Puertas, F.; Santos, H.; Palacios, M.; Martínez-Ramírez, Sagrario

    2005-01-01

    A study was conducted on the effect of a polycarboxylate (PC) admixture on the mechanical, mineralogical, microstructural and rheological behaviour of Portland cement pastes. It was observed that the presence of PC admixture retards the initial cement hydration reactions, although this effect may be offset by possible increased diffusion in later stages. Additionally, the PC admixtures produce a few alterations in the structure and composition of the formed C–S–H gel. The addition of 1% PC...

  7. The Influence of Admixtures on the Technological Properties of Fresh Concrete Mixture

    OpenAIRE

    Albertas KLOVAS; Daukšys, Mindaugas

    2015-01-01

    In this research superplasticizing (SP), air voids removing (AVR), viscosity modifying (VM) and air entraining admixtures (AE) were used. The dosage of admixtures was chosen from minimum to maximum values recommended by the manufacturers. To sum up, 7 concrete mixture compositions with SP, 6 with AVR and 6 with VM and the last 6 with AE admixture were prepared. Water and cement ratio for all the compositions was kept at the same value. According to the results obtained, the usage of SP admixt...

  8. Dating the age of admixture via wavelet transform analysis of genome-wide data.

    Science.gov (United States)

    Pugach, Irina; Matveyev, Rostislav; Wollstein, Andreas; Kayser, Manfred; Stoneking, Mark

    2011-01-01

    We describe a PCA-based genome scan approach to analyze genome-wide admixture structure, and introduce wavelet transform analysis as a method for estimating the time of admixture. We test the wavelet transform method with simulations and apply it to genome-wide SNP data from eight admixed human populations. The wavelet transform method offers better resolution than existing methods for dating admixture, and can be applied to either SNP or sequence data from humans or other species. PMID:21352535

  9. Dating the age of admixture via wavelet transform analysis of genome-wide data

    OpenAIRE

    Pugach, Irina; Matveyev, Rostislav; Wollstein, Andreas; Kayser, Manfred; Stoneking, Mark

    2011-01-01

    textabstractWe describe a PCA-based genome scan approach to analyze genome-wide admixture structure, and introduce wavelet transform analysis as a method for estimating the time of admixture. We test the wavelet transform method with simulations and apply it to genome-wide SNP data from eight admixed human populations. The wavelet transform method offers better resolution than existing methods for dating admixture, and can be applied to either SNP or sequence data from humans or other species.

  10. Experimental Study on Durability Improvement of Fly Ash Concrete with Durability Improving Admixture

    OpenAIRE

    Quan, Hong-zhu; Kasami, Hideo

    2014-01-01

    In order to improve the durability of fly ash concrete, a series of experimental studies are carried out, where durability improving admixture is used to reduce drying shrinkage and improve freezing-thawing resistance. The effects of durability improving admixture, air content, water-binder ratio, and fly ash replacement ratio on the performance of fly ash concrete are discussed in this paper. The results show that by using durability improving admixture in nonair-entraining fly ash concrete,...

  11. Practical handling of AIO admixtures – Guidelines on Parenteral Nutrition, Chapter 10

    Directory of Open Access Journals (Sweden)

    Stanga, Z.

    2009-11-01

    Full Text Available All-in-one admixtures (AIO-admixtures provide safe, effective and low-risk PN (parenteral nutrition for practically all indications and applications. Water, energy (carbohydrates and lipids, amino acids, vitamins and trace elements are infused together with PN either as industrially-manufactured AIO admixtures provided as two- or three-chamber bags (shelf life usually more than 12 months completed with electrolytes and micronutrients where appropriate or as individually compounded ready-to-use AIO admixtures (compounding, usually prepared by a pharmacy on either a daily or weekly basis and stored at 2–8°C. Physico-chemical and microbial stability of an AIO admixture is essential for the safety and effectiveness of patient-specific PN, and its assurance requires specialist pharmaceutical knowledge. The stability should be documented for an application period of 24 (–48 hours. It is advisable to offer a limited selection of different PN regimes in each hospital. For reasons of drug and medication safety, PN admixtures prepared for individual patients must be correctly labelled and specifications for storage conditions must also be followed during transport. Monitoring is required where applicable. Micronutrients are usually administered separately to AIO admixtures. In case compatibility and stability have been well documented trace elements and/or combination preparations including water-soluble or water-soluble/fat soluble vitamin supplements can be added to PN admixtures under strict aseptic conditions. AIO admixtures are usually not used as vehicles for drugs (incompatibilities.

  12. Effect of Anti-freezing Admixtures on Alkali-silica Reaction in Mortars

    Institute of Scientific and Technical Information of China (English)

    LIU Junzhe; LI Yushun; LV Lihua

    2005-01-01

    The influence of anti-freezing admixture on the alkali aggregate reaction in mortar was analyzed with accelerated methods. It is confirmed that the addition of sodium salt ingredients of anti-freezing admixture accelerates the alkali silica reaction to some extent, whereas calcium salt ingredient of anti-freezing admixture reduces the expansion of alkali silica reaction caused by high alkali cement. It is found that the addition of the fly ash considerably suppresses the expansion of alkali silica reaction induced by the anti-freezing admixtures.

  13. The influence of shrinkage reducing admixtures on plastic shrinkage

    Directory of Open Access Journals (Sweden)

    Mora, J.

    2003-12-01

    Full Text Available Shrinkage reducing admixtures (SRAs are viable alternatives for reducing plastic shrinkage cracking in concrete. The objective of the present paper is to study early age plastic shrinkage in restrained concrete elements, where three different SRAs have been used. The influence of the admixture is analyzed through the following measurements: capillary pressure, evaporation, temperature evolution, crack evolution and settlement. The tests for studying the cracking and deformation were made on two different configurations (i.e., restrained prisms with reduced cross-section and restrained panel, in a wind tunnel, with controlled wind temperature and velocity. The conclusions obtained indicate the viability of the use of this type of admixture and the usefulness of the test methods.

    Los aditivos reductores de retracción (SRAs se plantean, hoy en día, como una alternativa viable para reducir la fisuración por retracción plástica. El objetivo del presente artículo es conocer mejor y predecir el comportamiento a primeras edades de la retracción plástica en elementos estructurales coaccionados, a los que se les ha añadido diversos aditivos reductores de retracción (tres tipos diferentes. Esta influencia se analiza a través de las siguientes propiedades: presión capilar, evaporación, evolución de temperaturas, evolución de fisuración, y deformaciones verticales de asentamiento. Los ensayos para estudiar la fisuración y las deformaciones se han realizado sobre diferentes configuraciones (prisma restringido con estrangulamiento y panel restringido, en un túnel de viento, con temperaturas y velocidades de viento controladas. Las conclusiones obtenidas señalan la viabilidad del empleo de este tipo de aditivos y la bondad de los métodos experimentales utilizados.

  14. A genomewide admixture mapping panel for Hispanic/Latino populations.

    Science.gov (United States)

    Mao, Xianyun; Bigham, Abigail W; Mei, Rui; Gutierrez, Gerardo; Weiss, Ken M; Brutsaert, Tom D; Leon-Velarde, Fabiola; Moore, Lorna G; Vargas, Enrique; McKeigue, Paul M; Shriver, Mark D; Parra, Esteban J

    2007-06-01

    Admixture mapping (AM) is a promising method for the identification of genetic risk factors for complex traits and diseases showing prevalence differences among populations. Efficient application of this method requires the use of a genomewide panel of ancestry-informative markers (AIMs) to infer the population of origin of chromosomal regions in admixed individuals. Genomewide AM panels with markers showing high frequency differences between West African and European populations are already available for disease-gene discovery in African Americans. However, no such a map is yet available for Hispanic/Latino populations, which are the result of two-way admixture between Native American and European populations or of three-way admixture of Native American, European, and West African populations. Here, we report a genomewide AM panel with 2,120 AIMs showing high frequency differences between Native American and European populations. The average intermarker genetic distance is ~1.7 cM. The panel was identified by genotyping, with the Affymetrix GeneChip Human Mapping 500K array, a population sample with European ancestry, a Mesoamerican sample comprising Maya and Nahua from Mexico, and a South American sample comprising Aymara/Quechua from Bolivia and Quechua from Peru. The main criteria for marker selection were both high information content for Native American/European ancestry (measured as the standardized variance of the allele frequencies, also known as "f value") and small frequency differences between the Mesoamerican and South American samples. This genomewide AM panel will make it possible to apply AM approaches in many admixed populations throughout the Americas. PMID:17503334

  15. Mirror matter admixtures in K_S to gamma gamma

    CERN Document Server

    Sánchez-Colón, G; Sanchez-Colon, Gabriel; Garcia, Augusto

    2006-01-01

    The latest measurement of the K_S to gamma gamma branching ratio clearly shows an enhancement over the current theoretical prediction. As in other K and B meson decays, this invites to consider the possibility of the contribution of new physics. We study a particular form of the latter, which may be referred to as manifest mirror symmetry. The experimental data are described using previously determined values for the mixing angles of the admixtures of mirror matter in ordinary hadrons and by assuming that for pi^0, eta, eta', the mirror decay amplitudes have the same magnitudes as their ordinary counterparts.

  16. Symmetry limit properties of decay amplitudes with mirror matter admixtures

    CERN Document Server

    Sánchez-Colón, G; Sanchez-Colon, Gabriel; Garcia, Augusto

    2006-01-01

    We extend our previous analysis on the symmetry limit properties of non-leptonic and weak radiative decay amplitudes of hyperons in a scheme of mirror matter admixtures in physical hadrons to include the two-body non-leptonic decays of $\\Omega^-$ and the two photon and two pion decays of kaons. We show that the so-called parity-conserving amplitudes predicted for all the decays vanish in the strong flavor SU(3) symmetry limit. We also establish the specific conditions under which the corresponding so-called parity-violating amplitudes vanish in the same limit.

  17. Whistler Solitons in Plasma with Anisotropic Hot Electron Admixture

    Science.gov (United States)

    Khazanov, G. V.; Krivorutsky, E. N.; Gallagher, D. L.

    1999-01-01

    The longitudinal and transverse modulation instability of whistler waves in plasma, with a small admixture of hot anisotropic electrons, is discussed. If the hot particles temperature anisotropy is positive, it is found that, in such plasma, longitudinal perturbations can lead to soliton formation for frequencies forbidden in cold plasma. The soliton is enriched by hot particles. The frequency region unstable to transverse modulation in cold plasma in the presence of hot electrons is divided by stable domains. For both cases the role of hot electrons is more significant for whistlers with smaller frequencies.

  18. Effect of polycarboxylate admixture structure on cement paste rheology

    OpenAIRE

    Aranda, M. A. G.; De la Torre, A.G.; Puertas, F.; Palacios, M.; Alonso, M M

    2007-01-01

    The purpose of the present study was to analyze the effect of the structural differences in four polycarboxylate and polyether admixtures on the rheological properties of cement pastes with different chemical and mineralogical compositions and different active additions (CEM I 42.5 R, CEM I 52.5 R, CEM I 52.5 N/SR, CEM II/AV 42.5R, CEM II/B-L 32.5 R, CEM III/B 32.5R, BL I 52.5R and CAC – European standard EN 197-1:2000). The results of the minislump test concurred with the variations ob...

  19. Influence of chloride admixtures on cement matrix durability

    International Nuclear Information System (INIS)

    The influence of various inorganic salts, as chloride admixtures to Portland cement, on the mechanical properties and the durability of the matrix has been studied. The salts used in this study are chromium, nickel and cadmium chlorides. Improved compressive strength values are obtained which have been correlated to the stable metal hydroxide formation in high pH environment. Under static water conditions at 500C, hydrolyzed chloride ions exhibit adverse effects on the matrix durability through rapid release of calcium as calcium chloride in the initial period of leaching. On the contrary, enhanced matrix durability is obtained on long term leaching in the case of cement containing chromium chloride

  20. Incorporation of Mineral Admixtures in Sustainable High Performance Concrete

    Directory of Open Access Journals (Sweden)

    Nima Farzadnia

    2011-07-01

    Full Text Available Concrete is a widely used construction material around the world, and its properties have been undergoing changes through technological advancement. Numerous types of concrete have been developed to enhance the different properties of concrete. So far, this development can be divided into four stages. The earliest is the traditional normal strength concrete which is composed of only four constituent materials, which are cement, water, fine and coarse aggregates. With a fast population growth and a higher demand for housing and infrastructure, accompanied by recent developments in civil engineering, such as high-rise buildings and long-span bridges, higher compressive strength concrete was needed. At the beginning, reducing the water-cement ratio was the easiest way to achieve the high compressive strength. Thereafter, the fifth ingredient, a water reducing agent or super plasticizer, was indispensable. However, sometimes the compressive strength was not as important as some other properties, such as low permeability, durability and workability. Thus, high performance concrete was proposed and widely studied at the end of the last century. Currently, high-performance concrete is used in massive volumes due to its technical and economic advantages. Such materials are characterized by improved mechanical and durability properties resulting from the use of chemical and mineral admixtures as well as specialized production processes. This paper reviews the incorporation of mineral admixtures in binary, ternary and quaternary blended mortars in concrete.

  1. Physicochemical compatibility of nebulizable drug admixtures containing colistimethate and tobramycin.

    Science.gov (United States)

    Wollstadt, A; Krämer, I; Kamin, W

    2013-09-01

    Inhalation therapy with nebulizable antibiotic drugs is a mainstay in treating Pseudomonas aeruginosa infections in cystic fibrosis patients. The combination of tobramycin and colistin was found to be superior to monotherapy in killing P. aeruginosa in biofilms. The simultaneous inhalation of tobramycin and colistin might be an option to increase the compliance of patients. The objective of this in-vitro study was to determine whether admixtures of inhalation solutions containing colistin methanesulfonate (CMS) and tobramycin are physicochemically compatible. Physical compatibility was determined by measuring pH and osmolality. Chemical compatibility was determined by testing the antibiotic activity of the mixtures by the pharmacopoeial microbiological assay and comparing the results to those of standard solutions. Samples were analyzed immediately after mixing and after 24 h. Values of pH and osmolality remained unchanged and in physiologically acceptable ranges. Neither for colistin methanesulfonate (CMS) nor for tobramycin losses of antibiotic potency were registered at any time. Admixtures of nebulizer solutions containing CMS and tobramycin were shown to be physicochemically compatible. Further investigations are needed to determine whether drug delivery is affected by mixing the nebulizer solutions to ensure that simultaneous inhalation is recommendable. PMID:24147342

  2. Fly Ash Admixture and its Influence on Alitic Type Cement Concrete Permeability

    OpenAIRE

    Rujanu, Mircea; Rujanu, Bogdan

    2012-01-01

    Experimental and theoretical studies pointed that adding fly ash in concrete composition, could favour its impermeability characteristic improvement. It is known, also, that fly ash admixture achieves cement dosage reduction, so that concrete will be cheaper, and in this conditions it is important to analyse fly ash admixture influence on impermeability degree, too.

  3. Genome-wide Ancestry Patterns in Rapanui Suggest Pre-European Admixture with Native Americans

    DEFF Research Database (Denmark)

    Moreno-Mayar, J. Víctor; Rasmussen, Simon; Seguin-Orlando, Andaine;

    2014-01-01

    . We found a mostly Polynesian ancestry among Rapanui and detected genome-wide patterns consistent with Native American and European admixture. By considering the distribution of local ancestry tracts of eight unrelated Rapanui, we found statistical support for Native American admixture dating to AD...

  4. Dating the age of admixture via wavelet transform analysis of genome-wide data

    NARCIS (Netherlands)

    I. Pugach (Irina); R. Matveyev (Rostislav); A. Wollstein (Andreas); M.H. Kayser (Manfred); M. Stoneking (Mark)

    2011-01-01

    textabstractWe describe a PCA-based genome scan approach to analyze genome-wide admixture structure, and introduce wavelet transform analysis as a method for estimating the time of admixture. We test the wavelet transform method with simulations and apply it to genome-wide SNP data from eight admixe

  5. The application study of polycarboxylates water-reducing admixture in passenger dedicated line engineering%The application study of polycarboxylates water-reducing admixture in passenger dedicated line engineering

    Institute of Scientific and Technical Information of China (English)

    Huang Zhijiu

    2012-01-01

    Polycarboxylate water-reducing admixture possesses the capability which could meet with the comprehensive performance of high performance concrete used in passenger dedicated line engineering. The problems of polycarboxylates water-reducing admixtures existed in the engineering application of were analyzed. At present the key for polycarboxylates application was to settle the compatibility between the water-reducing admixture and the cement and to keep the quality retention of this admixture.

  6. Admixture analysis and stocking impact assessment in brown trout ( Salmo trutta ), estimated with incomplete baseline data

    DEFF Research Database (Denmark)

    Hansen, Michael Møller; Eg Nielsen, Einar; Bekkevold, Dorte;

    2001-01-01

    Studies of genetic interactions between wild and domesticated fish are often hampered by unavailability of samples from wild populations prior to population admixture. We assessed the utility of a new Bayesian method, which can estimate individual admixture coefficients even with data missing from...... the populations contributing to admixture. We applied the method to analyse the genetic contribution of domesticated brown trout (Salmo trutta) in samples of anadromous trout from two stocked populations with no genetic data available before stocking. Further, we estimated population level admixture proportions...... by the mean of individual admixture coefficients. This method proved more informative than a multidimensional scaling analysis of individual-based genetic distances and assignment tests. The results showed almost complete absence of stocked, domesticated trout in samples of trout from the rivers. Consequently...

  7. EFFECTS OF CHEMICAL ADMIXTURES ON SPECIALITIES OF HARDENED CONCRETE USED IN READY CONCRETE PRODUCTION IN ESKİŞEHİR

    OpenAIRE

    TOPÇU, İlker Bekir; IŞIKDAĞ, Burak; Özgür TATAR

    2006-01-01

    In this study polls were taken from different ready mixed concrete firms in Eskişehir. Chemical admixtures used in concrete production were investigated according to the polls, and some information about chemical admixtures was obtained. Compressive strengths of concrete specimens manufactured by ready mixed concrete firms were evaluated, and results were investigated due to different types and proportions of admixtures used in concrete. Chemical admixtures were compared to each other at the ...

  8. Used cooking oil as a green chemical admixture in concrete

    International Nuclear Information System (INIS)

    According to National Statistics Approximately 1.35 billion gallons of used oil are generated yearly. With the increasing of the concrete usage, a more cost effective and economic new type of admixtures may give positive impacts on the Malaysian construction building as well as worldwide concrete usage. To objective of this is study is to investigate the effect of used cooking oil in terms of slump test, compressive strength test and rebound hammer. By adding the used cooking oil to the concrete, it increases the slump value from 4% to 72%. And the compressive strength have an increment from 1% to 16.8%. The used cooking oil obtains the optimum contribution to the concrete mix proportion of containing used cooking oil of 1.50% from the cement content. The result of used cooking oil from experimental program of slump value and compressive strength proved that used cooking oil have positive effects on replacement of commercially available superplasticizer.

  9. Used cooking oil as a green chemical admixture in concrete

    Science.gov (United States)

    Salmia, B.; Che Muda, Zakaria; Ashraful Alam, Md; Sidek, L. M.; Hidayah, B.

    2013-06-01

    According to National Statistics Approximately 1.35 billion gallons of used oil are generated yearly. With the increasing of the concrete usage, a more cost effective and economic new type of admixtures may give positive impacts on the Malaysian construction building as well as worldwide concrete usage. To objective of this is study is to investigate the effect of used cooking oil in terms of slump test, compressive strength test and rebound hammer. By adding the used cooking oil to the concrete, it increases the slump value from 4% to 72%. And the compressive strength have an increment from 1% to 16.8%. The used cooking oil obtains the optimum contribution to the concrete mix proportion of containing used cooking oil of 1.50% from the cement content. The result of used cooking oil from experimental program of slump value and compressive strength proved that used cooking oil have positive effects on replacement of commercially available superplasticizer.

  10. Techniques and methods of characterization of admixtures for the concrete

    Directory of Open Access Journals (Sweden)

    Palacios, M.

    2003-03-01

    Full Text Available Admixtures are defined as those products that are incorporated in the moment of the process of mixture of the concrete in a quantity not bigger than 5 by mass of the cement %, with relationship to the cement content in the concrete, with object of modifying the properties of the mixture in .state fresh and/or hardened. The behaviour of the admixtures depends on its chemical and ionic composition, the organic functional groups present, and the structure of the polymer and the distribution of molecular weight of the different polymers. In the present work the techniques and methods of characterization physical-chemistry, chemistry and ionic, structural, as well as of the polymers that constitute this admixtures, are described. A lot of techniques have been employed like: ionic chromatography, ultraviolet-visible spectroscopy (UV-VIS, Fourier transform infrared spectroscopy (FTIR, Fourier transform Raman spectroscopy (FT-Raman, nuclear magnetic resonance spectroscopy (1H-RMN and 13C-RMN, gel permeation chromatography (GPC. Two commercial admixtures have been selected to carry out this characterization, a superplastificant based on policarboxilates, and a reducer of the shrinkage based on polipropilenglycol.

    RESUMEN Se definen los aditivos como aquellos productos que son incorporados en el momento del amasado del hormigón en una cantidad no mayor del 5% en masa, con relación al contenido de cemento en el hormigón, con objeto de modificar las propiedades de la mezcla en estado fresco y/o endurecido. El comportamiento de los aditivos depende de su composición química e iónica, de los grupos funcionales orgánicos presentes, de la estructura del polímero y de la distribución de pesos moleculares de los diferentes polímeros que lo constituyen. En el presente trabajo se describen diferentes técnicas y métodos de caracterización físico-química, química e iónica, estructural, así como de los polímeros que

  11. Genetic admixture and population substructure in Guanacaste Costa Rica.

    Directory of Open Access Journals (Sweden)

    Zhaoming Wang

    Full Text Available The population of Costa Rica (CR represents an admixture of major continental populations. An investigation of the CR population structure would provide an important foundation for mapping genetic variants underlying common diseases and traits. We conducted an analysis of 1,301 women from the Guanacaste region of CR using 27,904 single nucleotide polymorphisms (SNPs genotyped on a custom Illumina InfiniumII iSelect chip. The program STRUCTURE was used to compare the CR Guanacaste sample with four continental reference samples, including HapMap Europeans (CEU, East Asians (JPT+CHB, West African Yoruba (YRI, as well as Native Americans (NA from the Illumina iControl database. Our results show that the CR Guanacaste sample comprises a three-way admixture estimated to be 43% European, 38% Native American and 15% West African. An estimated 4% residual Asian ancestry may be within the error range. Results from principal components analysis reveal a correlation between genetic and geographic distance. The magnitude of linkage disequilibrium (LD measured by the number of tagging SNPs required to cover the same region in the genome in the CR Guanacaste sample appeared to be weaker than that observed in CEU, JPT+CHB and NA reference samples but stronger than that of the HapMap YRI sample. Based on the clustering pattern observed in both STRUCTURE and principal components analysis, two subpopulations were identified that differ by approximately 20% in LD block size averaged over all LD blocks identified by Haploview. We also show in a simulated association study conducted within the two subpopulations, that the failure to account for population stratification (PS could lead to a noticeable inflation in the false positive rate. However, we further demonstrate that existing PS adjustment approaches can reduce the inflation to an acceptable level for gene discovery.

  12. The Complex Admixture History and Recent Southern Origins of Siberian Populations.

    Science.gov (United States)

    Pugach, Irina; Matveev, Rostislav; Spitsyn, Viktor; Makarov, Sergey; Novgorodov, Innokentiy; Osakovsky, Vladimir; Stoneking, Mark; Pakendorf, Brigitte

    2016-07-01

    Although Siberia was inhabited by modern humans at an early stage, there is still debate over whether it remained habitable during the extreme cold of the Last Glacial Maximum or whether it was subsequently repopulated by peoples with recent shared ancestry. Previous studies of the genetic history of Siberian populations were hampered by the extensive admixture that appears to have taken place among these populations, because commonly used methods assume a tree-like population history and at most single admixture events. Here we analyze geogenetic maps and use other approaches to distinguish the effects of shared ancestry from prehistoric migrations and contact, and develop a new method based on the covariance of ancestry components, to investigate the potentially complex admixture history. We furthermore adapt a previously devised method of admixture dating for use with multiple events of gene flow, and apply these methods to whole-genome genotype data from over 500 individuals belonging to 20 different Siberian ethnolinguistic groups. The results of these analyses indicate that there have been multiple layers of admixture detectable in most of the Siberian populations, with considerable differences in the admixture histories of individual populations. Furthermore, most of the populations of Siberia included here, even those settled far to the north, appear to have a southern origin, with the northward expansions of different populations possibly being driven partly by the advent of pastoralism, especially reindeer domestication. These newly developed methods to analyze multiple admixture events should aid in the investigation of similarly complex population histories elsewhere. PMID:26993256

  13. A factorial design study on the physical stability of 3-in-1 admixtures.

    Science.gov (United States)

    Li, L C; Sampogna, T P

    1993-11-01

    The effects of dextrose concentration, the compounding method, and storage conditions, on the physical stability of 3-in-1 admixtures were investigated using a 2n factorial design. The main effect of these three variables on the weight percent of oil globules larger than 5 microns (by HIAC) was found to be statistically significant. However, the effects of interaction amongst these variables, except the two-way interaction between dextrose concentration and storage conditions, were found to be statistically insignificant. A higher dextrose concentration was shown to enhance the physical stability of the admixtures, while low-temperature storage (three days at 5 degrees C) was more favourable for maintaining the physical stability of the admixtures with a low dextrose concentration. Although sequential pumping produced admixtures with a slightly lower final weight percentage of larger oil globules (> 5 microns), the method of compounding has the least impact on the physical stability of the admixtures in comparison with the other two variables evaluated in this study. The storage of the admixtures at room temperature for one day was shown to have a greater adverse effect on admixtures with a low dextrose concentration. PMID:7908042

  14. Finding new solutions in pediatric parenteral admixtures: how to improve quality and to deal with shortages

    Directory of Open Access Journals (Sweden)

    Dorota Watrobska-Swietlikowska

    2014-07-01

    Full Text Available Introduction: Pediatric parenteral nutrition enables normal growth even of preterm infants. Those children require, however, tailored parenteral nutrition and the creation of such can be challenging due to the risk of instability and shortages. Objective: Prototypical parenteral admixtures were created using different calcium salts (organic and inorganic and different lipid emulsions and tested for stability. 36 of parenteral admixtures containing two types of calcium salts: chloride or gluconolactobionate and different lipid emulsions (SMOFlipid® or Lipofundin MCT/LCT® were under investigation. Methods: Preliminary admixtures were prepared in two-chamber bags whereas lipid emulsions were placed separately in the second chamber. Pre-admixtures were stored for up to 21 days at +4ºC. Contents of the two chambers were combined at t = 0 or after 21 days of storage. Physical analysis of completed admixtures (visual inspection, microscopic observation, pH measurement and determination of the size distribution of oily droplets was carried out after 21 days of the storage. Stability of lipid, commercial emulsions stored in ethylene vinyl acetate (EVA bags for 42 days was also studied. Results: Irrespectively of the time of storage of preadmixtures and type of calcium salt and different lipid emulsions among 36 total parenteral admixtures only one showed signs of destabilization after preparation and one was unstable when stored for longer than 14 days. All other formulations were qualified to be stable during the study. All investigated commercial lipid emulsions were physically stable in EVA bags even when stored at room temperature. Conclusion: The study proved that it was possible to store pre-admixture in EVA bags for 21 days at 4ºC as well as that CAN (critical aggregation number and CaxP (the products of multiplication of calcium and phosphate ions concentration should not be used as reliable indicators of admixture physical stability. No

  15. EFFECTS OF CHEMICAL ADMIXTURES ON SPECIALITIES OF HARDENED CONCRETE USED IN READY CONCRETE PRODUCTION IN ESKİŞEHİR

    Directory of Open Access Journals (Sweden)

    İlker Bekir TOPÇU

    2006-01-01

    Full Text Available In this study polls were taken from different ready mixed concrete firms in Eskişehir. Chemical admixtures used in concrete production were investigated according to the polls, and some information about chemical admixtures was obtained. Compressive strengths of concrete specimens manufactured by ready mixed concrete firms were evaluated, and results were investigated due to different types and proportions of admixtures used in concrete. Chemical admixtures were compared to each other at the end of the investigation, and the results showed, chemical admixtures gain concrete different characteristics according to various environmental conditions. The past investigations showed that the differences between chemical admixtures were most occurred owing to environmental conditions (season, temperature etc., and chemical admixtures were classified according to seasons by users.

  16. Effect of polycarboxylate admixture structure on cement paste rheology

    Directory of Open Access Journals (Sweden)

    Aranda, M. A. G.

    2007-06-01

    Full Text Available The purpose of the present study was to analyze the effect of the structural differences in four polycarboxylate and polyether admixtures on the rheological properties of cement pastes with different chemical and mineralogical compositions and different active additions (CEM I 42.5 R, CEM I 52.5 R, CEM I 52.5 N/SR, CEM II/AV 42.5R, CEM II/B-L 32.5 R, CEM III/B 32.5R, BL I 52.5R and CAC – European standard EN 197-1:2000. The results of the minislump test concurred with the variations observed in the values of the rheological parameters (shear stress and plastic viscosity. The structural characteristic of the admixtures found to play the most prominent role in their fluidizing effect was the proportion of carboxylate (CG and polyether (EG group components. In cements characteristics such as fineness and the C3A/calcium sulphate and C3S/C3A ratios were also observed to be essential to admixture effectiveness. In this regard, the rheological parameters varied most widely in CEM I 52.5N/SR pastes and least in BL I 52.5R cement pastes. Of the additioned cements, the CEM III/B 32.5R pastes, which contained granulated blast furnace slag, showed the highest rises in flowability. Finally, the fluidizing effect of polycarboxylate superplasticizers was much more intense in calcium aluminate cements, although flowability declined rapidly in this material.El objetivo de este trabajo ha sido estudiar el efecto de las diferencias estructurales de cuatro aditivos basados en policarboxilatos y poliéteres sobre las propiedades reológicas de pastas de cemento con diferente composición química, mineralógica y con distintas adiciones activas (CEM I 42,5 R, CEM I 52,5 R, CEM I 52,5 N/SR, CEM II/AV 42,5R, CEM II/ B-L 32,5 R, CEM III/B 32,5R, BL I 52,5R y CAC - Norma EN 197-1:2000. Los resultados obtenidos sobre la fluidez de la pasta en el ensayo del “Minislump” coinciden con la evolución de los valores de los parámetros reológicos (esfuerzo de

  17. Stability of admixture containing morphine sulfate, bupivacaine hydrochloride, and clonidine hydrochloride in an implantable infusion system.

    Science.gov (United States)

    Classen, Ashley M; Wimbish, Gary H; Kupiec, Thomas C

    2004-12-01

    Intrathecal infusion is often performed using drug combinations. This study was conducted to evaluate the stability of the admixture of morphine sulfate, bupivacaine hydrochloride, and clonidine hydrochloride when used in an implantable pump under simulated clinical use conditions. SynchroMed implantable pumps were filled with an admixture and incubated at 37 degrees C for a period of 90 days. Drug admixture stored in glass vials at 4 degrees C and at 37 degrees C served as controls. Samples which included pump reservoir and catheter delivered aliquots were collected every 30 days and analyzed for drug concentrations using a stability-indicating HPLC method. All drugs contained in the admixture were stable and the original concentrations remained greater than 96%. Over 90 days, and with the pump at the simulated body temperature of 37 degrees C, there were no evident heat catalyzed or device catalyzed reactions. PMID:15589086

  18. Admixture enhanced controlled low-strength material for direct underwater injection with minimal cross-contamination

    International Nuclear Information System (INIS)

    Commercially available admixtures have been developed for placing traditional concrete products under water. This paper evaluates adapting anti-washout admixture (AWA) and high range water reducing admixture (HRWRA) products to enhance controlled low-strength materials (CLSMs) for underwater placement. A simple experimental scale model (based on dynamic and geometric similitude) of typical grout pump emplacement equipment has been developed to determine the percentage of cementing material washed out. The objective of this study was to identify proportions of admixtures and underwater CLSM emplacement procedures which would minimize the cross-contamination of the displaced water while maintaining the advantages of CLSM. Since the displaced water from radioactively contaminated systems must be subsequently treated prior to release to the environment, the amount of cross-contamination is important for cases in which cementing material could form hard sludges in a water treatment facility and contaminate the in-place CLSM stabilization medium

  19. A Genome-Wide Search for Greek and Jewish Admixture in the Kashmiri Population

    Science.gov (United States)

    Tashi, Tsewang; Lorenzo, Felipe Ramos; Feusier, Julie Ellen; Mir, Hyder

    2016-01-01

    The Kashmiri population is an ethno-linguistic group that resides in the Kashmir Valley in northern India. A longstanding hypothesis is that this population derives ancestry from Jewish and/or Greek sources. There is historical and archaeological evidence of ancient Greek presence in India and Kashmir. Further, some historical accounts suggest ancient Hebrew ancestry as well. To date, it has not been determined whether signatures of Greek or Jewish admixture can be detected in the Kashmiri population. Using genome-wide genotyping and admixture detection methods, we determined there are no significant or substantial signs of Greek or Jewish admixture in modern-day Kashmiris. The ancestry of Kashmiri Tibetans was also determined, which showed signs of admixture with populations from northern India and west Eurasia. These results contribute to our understanding of the existing population structure in northern India and its surrounding geographical areas. PMID:27490348

  20. Combined effect of expansive and shrinkage reducing admixtures to obtain stable and durable mortars

    International Nuclear Information System (INIS)

    In order to improve the dimensional stability of cement based mortars, the effects produced on cement hydration of a shrinkage reducer (propyleneglycol ether based-SRA) and an expansive admixture (calcium oxide based-EXP) were investigated. Mortar samples (prepared without admixtures or with SRA or EXP or SRA and EXP) were compared through compressive strength measurements, water evaporation, restrained shrinkage and restrained expansion measurements. Setting time and free expansion were also detected on cement paste specimens. A synergistic effect on the shrinkage reduction was observed when the shrinkage reducing admixture and the expansive agent were used together. In order to clarify this phenomenon, the hydration of cement pastes containing these kinds of admixtures was followed by ESEM-FEG (environmental scanning electron microscopy-field emission gun), TG (thermogravimetry), specific surface area measurements (by BET-Brunauer-Emmet-Teller-method) and XRDS (X-ray diffraction spectroscopy)

  1. $\\Sigma^-$ admixture in the $^{10}_\\Lambda$Li hypernucleus with a repulsive $\\Sigma$-nucleus potential

    CERN Document Server

    Lanskoy, D E

    2013-01-01

    $\\Sigma^-$ hyperon component of the $^{10}_\\Lambda$Li wave function is studied. The $\\Sigma^-$ admixture is vital for production of neutron-rich $\\Lambda$ hypernuclei via mesonic beams. We use a simplified shell model wave function for the $\\Lambda$ channel and calculate the $\\Sigma^-$ admixture directly from coupled equations. Probability of the $\\Sigma^-$ admixture for realistic repulsive $\\Sigma^-$-nucleus potentials is less by several times than that for attractive potentials and does not exceed $0.1\\%$. We conclude that the cross sections of the $^{10}\\mbox{B}(\\pi^-,K^+){}^{10}_\\Lambda\\mbox{Li}$ reaction measured at KEK cannot be explained by production via $\\Sigma^-$ admixture as a doorway state.

  2. Effect of alkohols as hardening-accelerating admixtures on the cement properties

    OpenAIRE

    Флейшер, Ганна Юріївна; Токарчук, Володимир Володимирович; Василькевич, Олександр Іванович; Свідерський, Валентин Анатолійович

    2014-01-01

    The effect of alcohols as hardening-accelerating admixtures on physicomechanical properties of cement, particularly strength indexes in early hardening period is investigated. Alcohols can be used as an effective hardening accelerators of cement. The effectiveness of the influence of alcohols on the cement properties depends on their spatial structure and the number of hydroxyl groups. It was found that the largest increase in the cement strength is promoted by individual admixtures of alcoho...

  3. Statistical Tests for Admixture Mapping with Case-Control and Cases-Only Data

    OpenAIRE

    Montana, Giovanni; Pritchard, Jonathan K

    2004-01-01

    Admixture mapping is a promising new tool for discovering genes that contribute to complex traits. This mapping approach uses samples from recently admixed populations to detect susceptibility loci at which the risk alleles have different frequencies in the original contributing populations. Although the idea for admixture mapping has been around for more than a decade, the genomic tools are only now becoming available to make this a feasible and attractive option for complex-trait mapping. I...

  4. Finding new solutions in pediatric parenteral admixtures: how to improve quality and to deal with shortages

    OpenAIRE

    Dorota Watrobska-Swietlikowska; Anna Kwidzynska; Agnieszka Szlagatys-Sidorkiewicz; Malgorzata Sznitowska; Stanislaw Klek

    2014-01-01

    Introduction: Pediatric parenteral nutrition enables normal growth even of preterm infants. Those children require, however, tailored parenteral nutrition and the creation of such can be challenging due to the risk of instability and shortages. Objective: Prototypical parenteral admixtures were created using different calcium salts (organic and inorganic) and different lipid emulsions and tested for stability. 36 of parenteral admixtures containing two types of calcium salts: chloride or gluc...

  5. Diffusion Decay Coefficient for Chloride Ions of Concrete Containing Mineral Admixtures

    OpenAIRE

    Jae-Im Park; Kwang-Myong Lee; Soon-Oh Kwon; Su-Ho Bae; Sang-Hwa Jung; Sung-Won Yoo

    2016-01-01

    The diffusion coefficient for chloride ions and the diffusion decay coefficient for chloride ions are essential variables for a service life evaluation of concrete structures. They are influenced by water-binder ratio, exposure condition, curing temperature, cement type, and the type and use of mineral admixture. Mineral admixtures such as ground granulated blast furnace slag, fly ash, and silica fume have been increasingly used to improve resistance against chloride ions penetration in concr...

  6. Admixture Mapping Identifies a Quantitative Trait Locus Associated with FEV1/FVC in the COPDGene Study

    OpenAIRE

    Parker, Margaret M.; Foreman, Marilyn G; Abel, Haley J.; Rasika A Mathias; Hetmanksi, Jacqueline B.; Crapo, James D.; Silverman, Edwin K.; Terri H Beaty

    2014-01-01

    African Americans are admixed with genetic contributions from European and African ancestral populations. Admixture mapping leverages this information to map genes influencing differential disease risk across populations. We performed admixture and association mapping in 3300 African American current or former smokers from the COPDGene Study. We analyzed estimated local ancestry and SNP genotype information to identify regions associated with FEV1/FVC, the ratio of forced expiratory volume in...

  7. A Novel Admixture-Based Pharmacogenetic Approach to Refine Warfarin Dosing in Caribbean Hispanics.

    Directory of Open Access Journals (Sweden)

    Jorge Duconge

    Full Text Available This study is aimed at developing a novel admixture-adjusted pharmacogenomic approach to individually refine warfarin dosing in Caribbean Hispanic patients.A multiple linear regression analysis of effective warfarin doses versus relevant genotypes, admixture, clinical and demographic factors was performed in 255 patients and further validated externally in another cohort of 55 individuals.The admixture-adjusted, genotype-guided warfarin dosing refinement algorithm developed in Caribbean Hispanics showed better predictability (R2 = 0.70, MAE = 0.72mg/day than a clinical algorithm that excluded genotypes and admixture (R2 = 0.60, MAE = 0.99mg/day, and outperformed two prior pharmacogenetic algorithms in predicting effective dose in this population. For patients at the highest risk of adverse events, 45.5% of the dose predictions using the developed pharmacogenetic model resulted in ideal dose as compared with only 29% when using the clinical non-genetic algorithm (p<0.001. The admixture-driven pharmacogenetic algorithm predicted 58% of warfarin dose variance when externally validated in 55 individuals from an independent validation cohort (MAE = 0.89 mg/day, 24% mean bias.Results supported our rationale to incorporate individual's genotypes and unique admixture metrics into pharmacogenetic refinement models in order to increase predictability when expanding them to admixed populations like Caribbean Hispanics.ClinicalTrials.gov NCT01318057.

  8. Multiway admixture deconvolution using phased or unphased ancestral panels.

    Science.gov (United States)

    Churchhouse, Claire; Marchini, Jonathan

    2013-01-01

    We describe a novel method for inferring the local ancestry of admixed individuals from dense genome-wide single nucleotide polymorphism data. The method, called MULTIMIX, allows multiple source populations, models population linkage disequilibrium between markers and is applicable to datasets in which the sample and source populations are either phased or unphased. The model is based upon a hidden Markov model of switches in ancestry between consecutive windows of loci. We model the observed haplotypes within each window using a multivariate normal distribution with parameters estimated from the ancestral panels. We present three methods to fit the model-Markov chain Monte Carlo sampling, the Expectation Maximization algorithm, and a Classification Expectation Maximization algorithm. The performance of our method on individuals simulated to be admixed with European and West African ancestry shows it to be comparable to HAPMIX, the ancestry calls of the two methods agreeing at 99.26% of loci across the three parameter groups. In addition to it being faster than HAPMIX, it is also found to perform well over a range of extent of admixture in a simulation involving three ancestral populations. In an analysis of real data, we estimate the contribution of European, West African and Native American ancestry to each locus in the Mexican samples of HapMap, giving estimates of ancestral proportions that are consistent with those previously reported. PMID:23136122

  9. Influences of a New Admixture MX on Concrete Durability

    Institute of Scientific and Technical Information of China (English)

    MA Baoguo; DONG Rongzhen; ZHU Hongbo; ZHANG Li; ZHONG Kaihong; HE Xingyang; LI Zongjin

    2005-01-01

    The performance of concrete with a new admixture MX was studied by using the freeze-thaw cycle, permeability and chemical attack test. The experimental results show that MX improves the durability of concrete. Within the optimum proportion ranges from 0.1%to 1%,the compressive strength of concrete after freeze-thaw is increased by 20%-50%,and Young's modulus can be increased by 3.76-5.64 times.The strength and weight loss of concrete with 0.4%MX are respectively decreased by 28% and 60% after hydrochloric acid attack.The strength and weight loss of concrete with 0.4% MX are decreased by 5%-20% after sulfuric acid and sodium sulfate attack.The permeability of concrete with 1% MX at 28 days can be decreased by more than 30%. The investigation of the negative temperature property of MX and analysis on concrete composition and microstructure by MIP reveal that the heat conduction is resisted and the freezing procedure of solution in concrete pore is retarded due to the adding of MX. Moreover,the pore structure of concrete with MX is improved, thus improving the durability. Based on this study, a resistance model of MX to block the heat and mass transference was proposed, and the mechanism of durability improvement of concrete with MX was explained.

  10. A slide-rule for assessment of venous admixture.

    Science.gov (United States)

    Zetterström, H

    1989-04-01

    Determination of venous admixture (physiological shunt, Qva/Qt) requires analysis of both arterial and mixed venous blood. When a pulmonary arterial catheter is not in use, the pulmonary oxygenating capacity may be assessed from arterial blood gas data, the fraction of inspired oxygen (FIO2) and an assumed value of the arterial-mixed venous oxygen content difference. To facilitate this process, a slide-rule based on the "virtual shunt" concept is presented. It permits rapid assessment of Qva/Qt from known values of arterial oxygen tension (PaO2) or saturation (SaO2) and FIO2 and may promote the choice of appropriate FIO2. The limitations of the slide-rule were studied theoretically and its validity was tested by comparing 100 determinations of virtual shunt with the corresponding Qva/Qt values. The slide-rule was found to estimate Qva/Qt more accurately than commonly used oxygenation indices such as the PaO2/FIO2 ratio. PMID:2499154

  11. Extensive Admixture and Selective Pressure Across the Sahel Belt.

    Science.gov (United States)

    Triska, Petr; Soares, Pedro; Patin, Etienne; Fernandes, Veronica; Cerny, Viktor; Pereira, Luisa

    2015-12-01

    Genome-wide studies of African populations have the potential to reveal powerful insights into the evolution of our species, as these diverse populations have been exposed to intense selective pressures imposed by infectious diseases, diet, and environmental factors. Within Africa, the Sahel Belt extensively overlaps the geographical center of several endemic infections such as malaria, trypanosomiasis, meningitis, and hemorrhagic fevers. We screened 2.5 million single nucleotide polymorphisms in 161 individuals from 13 Sahelian populations, which together with published data cover Western, Central, and Eastern Sahel, and include both nomadic and sedentary groups. We confirmed the role of this Belt as a main corridor for human migrations across the continent. Strong admixture was observed in both Central and Eastern Sahelian populations, with North Africans and Near Eastern/Arabians, respectively, but it was inexistent in Western Sahelian populations. Genome-wide local ancestry inference in admixed Sahelian populations revealed several candidate regions that were significantly enriched for non-autochthonous haplotypes, and many showed to be under positive selection. The DARC gene region in Arabs and Nubians was enriched for African ancestry, whereas the RAB3GAP1/LCT/MCM6 region in Oromo, the TAS2R gene family in Fulani, and the ALMS1/NAT8 in Turkana and Samburu were enriched for non-African ancestry. Signals of positive selection varied in terms of geographic amplitude. Some genomic regions were selected across the Belt, the most striking example being the malaria-related DARC gene. Others were Western-specific (oxytocin, calcium, and heart pathways), Eastern-specific (lipid pathways), or even population-restricted (TAS2R genes in Fulani, which may reflect sexual selection). PMID:26614524

  12. Spatial assessment of Argentinean genetic admixture with geographical information systems.

    Science.gov (United States)

    Diaz-Lacava, Amalia; Walier, Maja; Penacino, Gustavo; Wienker, Thomas F; Baur, Max P

    2011-08-01

    In recent years there has been much attention to Argentinean population stratification. We were interested in assessing population stratification from a geographical perspective and summarizing it in form of maps. We mapped the genetic admixture of the extant male population in central and northern Argentina on the basis of forensic Y-chromosomal haplotypes. We addressed the question which group of genetically similar individuals is predominant in this area. Haplotypes containing seven Y-chromosomal short tandem repeat polymorphisms (Y-STRs), also known as microsatellites - DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393 - were constructed for 145 individuals, recruited in 10 provinces. 97 distinct haplotypes were clustered into four clusters according to molecular distances. A genetic geostatistical analysis was conducted with the open-source geographical information system GRASS GIS. For each haplotype cluster, the according frequency was spatially interpolated over the total study area. Juxtaposing the interpolation surfaces, we screened point-wisely the maximal frequency as well as the label of the respective cluster. The screening results were combined in one summary map. We repeated this procedure for the second maximal frequencies. The resulting maps subdivide the study area into continuous regions comprising one predominant group of similar haplotypes. The first summary map divides the study area into three regions and the second summary map divides the area into four regions. The results of our analysis indicate that two groups of similar European haplotypes alternatively dominate the largest extension of the Argentinean territory. A third group, including South-American haplotypes, dominates the indigenous northwestern Argentinean area. The last group, including worldwide dispersed haplotypes, preponderates in frequency in second place in central Argentina. Our findings confirm a widespread European paternal ancestry, a substantial Amerindian

  13. Stability investigation of total parenteral nutrition admixture prepared in a hospital pharmacy

    Directory of Open Access Journals (Sweden)

    Mirković Dušica

    2008-01-01

    Full Text Available Background/Aim. In the cases when nutrition of patients can not be orally nor enterally performed, parenteral nutrition is a method of the therapy that provides more successful and rapid recovery. In that way, hospitalization can be significantly shorter, healing costs reduced and mortality minimized. Total parenteral nutrition (TPN admixtures are the most complex systems which contain amino acids, carbohydrates, lipid emulsion, macroelectrolytes (Na+, K+, Ca2+, Mg2+, Cl-, SO42-, PO43-, oligoelements, hydro- and liposoluble vitamines, heparin, insulin and water. Concerning the mentioned complexity, special attention should be payed to physicochemical and microbiological stability of a mixture, because of interactions among components, that can be very hard to analyze. The aim of this study was to investigate the problem of stability of TPN admixtures prepared in a hospital pharmacy. Methods. Admixture TPN was aseptically prepared in laminar air - flow environment on the basis of the specified order in supplementing components and additives to basic solutions. Solutions were kept in sterile multicompartment ethylene-vinyl-acetate bags. After preparation and slow homogenization, TPN admixtures were submitted to physicochemical and microbiological stability analyses in various period of time. The assessment of physical stability of TPN admixture was done on the basis of visual inspection, determination of pH value and measuring of particle size. The investigation of sterility and pyrogenic test were performed according to Ph. Yug. V regulations. Results. Physico-chemical and microbiological analyses were applied and no significant changes in visual sense, pH value and droplet size stability of the TPN admixture were observed during the period of 60 hours. The lipid droplets were smaller in size than 5 μm, that is the most common pharmacopoeia requirement. Conclusion. The results of our study confirmed that a TPN admixture prepared in a hospital

  14. Stability of total nutrient admixtures in a dual-chamber flexible container.

    Science.gov (United States)

    Tripp, M G; Menon, S K; Mikrut, B A

    1990-11-01

    The stability of total nutrient admixtures (TNAs) prepared from dextrose and amino acid injections commercially packaged in a dual-chamber container and a safflower-soybean oil fat emulsion was studied. The admixtures studied were divided into two groups. Group 1 admixtures represented 14 combinations of Aminosyn II, dextrose, and Liposyn II. Group 2 admixtures represented 10 combinations of Aminosyn II with Electrolytes, dextrose, and Liposyn II. Amino acid concentrations of 7, 8.5, and 10%, dextrose concentrations of 10, 20, 40, and 50%, and 10 and 20% fat emulsion were used. After the amino acid and dextrose injections were mixed in their original container (Nutrimix, Abbott Laboratories), the fat emulsion was added. One of two combinations of electrolytes and trace metals was then added. Multivitamins were added to each TNA just before 24-hour storage at room temperature (25 +/- 4 degrees C). Admixtures were tested initially and at the conclusion of storage periods of 24 hours at room temperature or nine days at 5 degrees C followed by 24 hours at room temperature. Measurements of pH, emulsion particle size, and weight percent of oil particles larger than 5 microns in diameter (HIAC) were made after visual inspection of each admixture. In selected admixtures, concentrations of individual amino acids and dextrose were determined by chromatographic techniques initially and at the conclusion of storage. The TNAs retained a uniform milk-like appearance throughout both storage periods. The pH values, particle size, HIAC measurements, and amino acid and dextrose concentrations remained essentially unchanged.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2126163

  15. ADSORPTION OF CHROMIUM (VI FROM AQUEOUS SOLUTIONS BY DIFFERENT ADMIXTURES – A BATCH EQUILIBRIUM TEST STUDY

    Directory of Open Access Journals (Sweden)

    K. SHIVA PRASHANTH KUMAR

    2014-08-01

    Full Text Available Wide variety of inorganic compounds such as nutrients and trace metals, organic chemicals, radioactive contaminants and pathogens are commonly present as contaminants in the groundwater. Migration of contaminants in soil involves important mechanisms such as molecular diffusion, dispersion under physical processes, adsorption, precipitation and oxidation - reduction under chemical processes and biodegradation under biological process. Cr (VI is a major and dangerous contaminant as per the ground water is concerned. There are numerous research work carried out with concentrated efforts by the researchers towards removal of Cr (VI contaminant from aqueous solutions. There are few studies relevant to Cr (VI removal with respect to utilization of low cost admixtures and also soil type. In the present study, different low cost admixtures like rice husk (RH, shredded tyre (ST and fly ash (FA are used to understand the performance in removal of Cr (VI from aqueous solution and also two different soil types are used along with the admixture. The results are discussed in terms of sorption capacity and performance of individual admixture and combination of admixture with soil in removal of contaminant. The fly ash, rice husk and shredded tyre admixtures are used and the results revealed that the shredded tyre showed higher performance in removal of contaminant concentration. Also, the soil which has more fine particle content (size<0.075 mm IS sieve showed reasonable reduction in concentration of contaminant at the lower levels of contaminant initial concentration. The sorption capacity results of Cr (VI contaminant, treated with various admixtures are further validated with the published work of other investigators. The shredded tyre (ST showed more adsorption capacity, i.e., 3.283 mg/g at pH of 4.8. For other admixtures, adsorption capacity value is varying in the range of 0.07 mg/g to 1.7 mg/g. Only in case of activated alumina and modified saw dust

  16. The Mechanism of the Eeffect of Mineral Admixtures on the Expansion of Aalkali-silica Reaction

    Institute of Scientific and Technical Information of China (English)

    WANG Aiqin; Niu Jishou; ZHANG Chengzhi

    2008-01-01

    On the base of the influence rule of silica fume, slag and fly ash on alkali-silica reaction under the condition of 70℃, the mechanism of the effect of mineral admixtures on alkali-silica reaction is studied further in the paper. The results show that the effects of mineral admixtures on alkali-silica reaction are mainly chemistry effect and surface physichemistry effect. Under suitable condition, the chemistry effect may make alkali-silica reaction to be inhibited effectively, but the physichemistry effect only make alkali-silica reaction to be delayed. The chemistry effect and the physichemistry effect of minerals admixture are relative to the content of Ca(OH)2 in system. Under the condition that there is a large quantity of Ca(OH)2, mineral admixture cannot inhibit alkali-silica reaction effectively. Only when Ca(OH)2 in the system is very less, it is possible that mineral admixture inhibits alkali-silica reaction effectively.

  17. Efficacy of Industrial waste admixture in Improving Engineering Performance of Clayey soil – A quantitative study

    Directory of Open Access Journals (Sweden)

    Kiran B. Biradar

    2014-09-01

    Full Text Available Infrastructure and industrialization serves as a back bone for a country’s economy. However due to rapid industrialization there exist a problem in the form of waste accumulation and subsequent problems due to their disposal & effects of waste. In infrastructure development, roads play a major role. In general pavement construction needs bulk quantities of good soil keeping in view of the service and longevity aspects. Due to limitation in availability of good soil, often the cost of projects escalates. An ideal solution lies for reducing project cost, increasing longevity and reduce accumulation of waste shall be through utilization of industrial waste combined with weak soil for pavement construction. Few types of waste materials namely crusher dust, fly ash and Steel slag waste are popular as admixtures in improving weak soils. This paper discusses the performance of admixtures in improving weak soil through mechanical stabilization. Results of tests on index and engineering properties of mechanically stabilized clayey soil with industrial waste admixtures namely, crusher dust, fly ash and steel slag are presented for different admixture contents and test conditions. A comparison is made based on improved performance. It is observed that Steel slag is proven to be effective over other types. From the results optimum content of admixture for a given improvement is suggested.

  18. Effect of Gum Arabic karroo as a Water-Reducing Admixture in Concrete

    Directory of Open Access Journals (Sweden)

    Rose Mbugua

    2016-01-01

    Full Text Available Concrete is one of the most popular construction materials in the world. Chemical admixtures are ingredients added to concrete to enhance its properties. However, most chemical admixtures on the market today are expensive, thereby making them out of reach for small consumers of concrete. In Africa, use of chemical admixtures is rare despite the harsh weather conditions. In the current study, Gum from Acacia karroo (GAK was used as a water-reducing admixture in concrete. A slump test, density and compressive strength were studied using different dosages of GAK while neat concrete was the control. Results showed that slump increased by 200% at a 2% dosage of GAK. This enabled reduction of water-to-binder (w/b ratio from 0.61 to 0.48 for samples with a 3% dosage. Reduction in w/b resulted in increased compressive strength of 37.03% above the control after 180 days of curing for a 3% dosage. XRD studies also showed a decreased rate of hydration in the presence of GAK in concrete. It was concluded that GAK can be used in concrete as a water-reducing admixture, which is environmentally-friendly, thus producing sustainable and greener concrete.

  19. Mechanical characteristics of hardened concrete with different mineral admixtures: a review.

    Science.gov (United States)

    Ayub, Tehmina; Khan, Sadaqat Ullah; Memon, Fareed Ahmed

    2014-01-01

    The available literature identifies that the addition of mineral admixture as partial replacement of cement improves the microstructure of the concrete (i.e., porosity and pore size distribution) as well as increasing the mechanical characteristics such as drying shrinkage and creep, compressive strength, tensile strength, flexural strength, and modulus of elasticity; however, no single document is available in which review and comparison of the influence of the addition of these mineral admixtures on the mechanical characteristics of the hardened pozzolanic concretes are presented. In this paper, based on the reported results in the literature, mechanical characteristics of hardened concrete partially containing mineral admixtures including fly ash (FA), silica fume (SF), ground granulated blast furnace slag (GGBS), metakaolin (MK), and rice husk ash (RHA) are discussed and it is concluded that the content and particle size of mineral admixture are the parameters which significantly influence the mechanical properties of concrete. All mineral admixtures enhance the mechanical properties of concrete except FA and GGBS which do not show a significant effect on the strength of concrete at 28 days; however, gain in strength at later ages is considerable. Moreover, the comparison of the mechanical characteristics of different pozzolanic concretes suggests that RHA and SF are competitive. PMID:24688443

  20. Regional admixture mapping and structured association testing: conceptual unification and an extensible general linear model.

    Directory of Open Access Journals (Sweden)

    David T Redden

    2006-08-01

    Full Text Available Individual genetic admixture estimates, determined both across the genome and at specific genomic regions, have been proposed for use in identifying specific genomic regions harboring loci influencing phenotypes in regional admixture mapping (RAM. Estimates of individual ancestry can be used in structured association tests (SAT to reduce confounding induced by various forms of population substructure. Although presented as two distinct approaches, we provide a conceptual framework in which both RAM and SAT are special cases of a more general linear model. We clarify which variables are sufficient to condition upon in order to prevent spurious associations and also provide a simple closed form "semiparametric" method of evaluating the reliability of individual admixture estimates. An estimate of the reliability of individual admixture estimates is required to make an inherent errors-in-variables problem tractable. Casting RAM and SAT methods as a general linear model offers enormous flexibility enabling application to a rich set of phenotypes, populations, covariates, and situations, including interaction terms and multilocus models. This approach should allow far wider use of RAM and SAT, often using standard software, in addressing admixture as either a confounder of association studies or a tool for finding loci influencing complex phenotypes in species as diverse as plants, humans, and nonhuman animals.

  1. Genetic admixture and lineage separation in a southern Andean plant

    Science.gov (United States)

    Morello, Santiago; Sede, Silvana M.

    2016-01-01

    varieties of E. alpina: var. alpina is more closely related to E. rubra and other species than to its own counterpart E. alpina var. carmelitana. Geometric morphometrics analysis (Elliptic Fourier descriptors) revealed significant differences in leaf shape between varieties. We found that diversity in Escallonia species analyzed here is geographically structured and deep divergence between varieties of E. alpina could be associated to ancient evolutionary events like orogeny. Admixture in southern populations could be the result of hybridization at the margins of the parental species’ distribution range. PMID:27179539

  2. Effect of Functional Chemical Admixtures on the Performance of Cement Asphalt Mortar Used in Ballastless Track

    Institute of Scientific and Technical Information of China (English)

    JIANG Jinyang; SHE Wei; LI Wei; PAN Li

    2015-01-01

    Chemical admixtures are of paramount importance to the performance of modern cement based composites. In this paper, we performed a series of tests to investigate the effects of chemical admixtures on the cement asphalt mortar (CA mortar), i e, compressive strength, frost resistance, permeability, fatigue resistance, pore structure and microstructure. In particular, two types of chemical admixtures were tested,i e, defoamer (tributyl phosphate (TBP)) and polycarboxylate superplasticizer (PS). The results indicate that the addition of TBP and PS eliminates big bubbles and promotes small non-connected pores forming in matrix. Besides, an optimum dosage of TBP and PS may be determined with respect to the frost resistance, permeability and fatigue resistance of CA mortar. Further elaborative discussions are presented as well as experimental evidences from mercury intrusion porosimetry, scanning electron microscopy and energy dispersive spectroscopy.

  3. African and non-African admixture components in African Americans and an African Caribbean population.

    Science.gov (United States)

    Murray, Tanda; Beaty, Terri H; Mathias, Rasika A; Rafaels, Nicholas; Grant, Audrey Virginia; Faruque, Mezbah U; Watson, Harold R; Ruczinski, Ingo; Dunston, Georgia M; Barnes, Kathleen C

    2010-09-01

    Admixture is a potential source of confounding in genetic association studies, so it becomes important to detect and estimate admixture in a sample of unrelated individuals. Populations of African descent in the US and the Caribbean share similar historical backgrounds but the distributions of African admixture may differ. We selected 416 ancestry informative markers (AIMs) to estimate and compare admixture proportions using STRUCTURE in 906 unrelated African Americans (AAs) and 294 Barbadians (ACs) from a study of asthma. This analysis showed AAs on average were 72.5% African, 19.6% European and 8% Asian, while ACs were 77.4% African, 15.9% European, and 6.7% Asian which were significantly different. A principal components analysis based on these AIMs yielded one primary eigenvector that explained 54.04% of the variation and captured a gradient from West African to European admixture. This principal component was highly correlated with African vs. European ancestry as estimated by STRUCTURE (r(2)=0.992, r(2)=0.912, respectively). To investigate other African contributions to African American and Barbadian admixture, we performed PCA on approximately 14,000 (14k) genome-wide SNPs in AAs, ACs, Yorubans, Luhya and Maasai African groups, and estimated genetic distances (F(ST)). We found AAs and ACs were closest genetically (F(ST)=0.008), and both were closer to the Yorubans than the other East African populations. In our sample of individuals of African descent, approximately 400 well-defined AIMs were just as good for detecting substructure as approximately 14,000 random SNPs drawn from a genome-wide panel of markers. PMID:20717976

  4. Y-STR diversity and ethnic admixture in White and Mulatto Brazilian population samples

    OpenAIRE

    Luzitano Brandão Ferreira; Celso Teixeira Mendes-Junior; Cláudia Emília Vieira Wiezel; Marcelo Rizzatti Luizon; Aguinaldo Luiz Simões

    2006-01-01

    We investigated 50 Mulatto and 120 White Brazilians for the Y-chromosome short tandem repeat (Y-STR) markers (DYS19, DYS390, DYS391, DYS392 and DYS393) and found 79 different haplotypes in the White and 35 in the Mulatto sample. Admixture estimates based on allele frequencies showed that the admixture of the white sample was 89% European, 6% African and 5% Amerindian while the Mulatto sample was 93% European and 7% African. Results were consistent with historical records of the directional ma...

  5. Y-STR diversity and ethnic admixture in White and Mulatto Brazilian population samples

    Directory of Open Access Journals (Sweden)

    Luzitano Brandão Ferreira

    2006-01-01

    Full Text Available We investigated 50 Mulatto and 120 White Brazilians for the Y-chromosome short tandem repeat (Y-STR markers (DYS19, DYS390, DYS391, DYS392 and DYS393 and found 79 different haplotypes in the White and 35 in the Mulatto sample. Admixture estimates based on allele frequencies showed that the admixture of the white sample was 89% European, 6% African and 5% Amerindian while the Mulatto sample was 93% European and 7% African. Results were consistent with historical records of the directional mating between European males and Amerindian or African females.

  6. Portland cement hydration in the presence of admixtures: black gram pulse and superplasticizer

    Directory of Open Access Journals (Sweden)

    Viveka Nand Dwivedi

    2008-12-01

    Full Text Available Effect of admixtures such as black gram pulse (BGP and sulfonated naphthalene based superplasticizer (SP on the hydration of Portland cement has been studied. The hydration characteristics of OPC in the presence of BGP and SP were studied with the help of non evaporable water content determinations, calorimetric method, Mössbauer spectroscopic and atomic force microscopic techniques. Results have shown that both BGP and SP get adsorbed at the surface of cement and its hydration products. The hydration of Portland cement is retarded in the presence of both the admixtures and nanosize hydration products are formed.

  7. Tensile strength of green concrete with fly ash and chemical admixtures

    Energy Technology Data Exchange (ETDEWEB)

    Ravina, D. [Technion-Israel Institute of Technology, Haifa (Israel). Faculty of Civil Engineering, National Building Research Institute

    1995-08-01

    The effect of Class F coal fly ash of marginal quality, as partial replacement for fine sand, and of chemical admixtures (water-reducing and retarding and high-rank water reducer) on the tensile strength of green concrete was investigated. The tests show that the fly ash significantly increased (by 25 to 40%) the tensile strength at 2 to 4 hours after mixing, compared with `similar` mixes without fly ash. On the other hand, the chemical admixtures with retarding properties significantly slowed down its growth over the first few hours. 4 refs., 7 figs., 6 tabs.

  8. Effects of drying conditions, admixtures and specimen size on shrinkage strains

    International Nuclear Information System (INIS)

    The paper presents the results of an experimental investigation on the effects of drying conditions, specimen size and presence of plasticizing admixture on the development of shrinkage strains. The measurements are taken in a harsh (50 deg. C and 5% R.H.) and a moderate environment (28 deg. C and 50% R.H.). The results include strain development at various levels of cross sections of concrete prisms. The drying conditions are found to be the dominant parameter affecting the shrinkage strain development particularly in specimens of smaller sizes. The effect of plasticizing admixture on shrinkage strains is negligible

  9. Further characterization of theobroma oil-beeswax admixtures as lipid matrices for improved drug delivery systems.

    Science.gov (United States)

    Attama, A A; Schicke, B C; Müller-Goymann, C C

    2006-11-01

    There is an increasing interest in lipid based drug delivery systems due to factors such as better characterization of lipidic excipients and formulation versatility and the choice of different drug delivery systems. It is important to know the thermal characteristics, crystal habit, texture, and appearance of a new lipid matrix when determining its suitability for use in certain pharmaceutical application. It is line with this that this research was embarked upon to characterize mixtures of beeswax and theobroma oil with a view to applying their admixtures in drug delivery systems such as solid lipid nanoparticles and nanostructured lipid carriers. Admixtures of theobroma oil and beeswax were prepared to contain 25% w/w, 50% w/w, and 75% w/w of theobroma oil. The admixtures were analyzed by differential scanning calorimetry (DSC), small angle X-ray diffraction (SAXD), wide angle X-ray diffraction (WAXD), and isothermal heat conduction microcalorimetry (IMC). The melting behavior and microstructures of the lipid admixtures were monitored by polarized light microscopy (PLM). Transmission electron microscopy (TEM) was used to study the internal structures of the lipid bases. DSC traces indicated that the higher melting peaks were roughly constant for the different admixtures, but lower melting peaks significantly increased (p beeswax in all the lipid matrix admixtures at all stages of the study. PLM micrographs revealed differences with regard to the thermal and optical behaviors depending on the composition of the matrix. The lipid matrix consisting of 75% w/w of theobroma oil showed a spherulite texture after 4 weeks of isothermal storage. Crystallization exotherms of lipid matrices containing 50% w/w and 25% w/w of theobroma oil showed change in modification after 30 min with the latter having a greater time-dependent crystallization. Generally, low non-integral Avrami exponents and growth rate constants were obtained for all the lipid matrices, with the admixture

  10. Chemical Stability of Admixtures Combining Ziconotide with Morphine or Hydromorphone During Simul ated Intrathecal Administration.

    Science.gov (United States)

    Shields, David; Montenegro, Rick; Ragusa, Matthew

    2005-10-01

    Objective.  To determine the stability of admixtures combining ziconotide with morphine or hydromorphone under simulated intrathecal infusions. Materials and Methods.  Admixtures of ziconotide (25 µg/mL) with morphine or hydromorphone (both at 35 mg/mL) were stored in Medtronic SynchroMed® II pumps at 37°C, and in control vials at 37°C and 5°C. Drug concentrations were determined using high-performance liquid chromatography. Results.  The ziconotide pump concentration with morphine declined to 79% of initial in 17 days, and to 88% of initial after 25 days with hydromorphone. Ziconotide concentrations in control vials stored at 37°C displayed similar rates of decay, but vials stored at 5°C exhibited no ziconotide loss. A statistical evaluation of the two combinations shows ziconotide-hydromorphone retaining 80% stability for 40 days (extrapolated), compared to 15 days for ziconotide-morphine. Morphine and hydromorphone were stable in the presence of ziconotide under all conditions. Conclusions.  Ziconotide-hydromorphone admixtures were more stable than ziconotide-morphine admixtures. PMID:22151554

  11. Admixture analysis and stocking impact assessment in brown trout ( Salmo trutta ), estimated with incomplete baseline data

    DEFF Research Database (Denmark)

    Hansen, Michael Møller; Eg Nielsen, Einar; Bekkevold, Dorte; Mensberg, Karen-Lise Dons

    2001-01-01

    . Consequently, stocking had little effect on improving fisheries. In one population, the genetic contribution by domesticated trout was small, whereas in the other population, some genetic impact was suggested. Admixture in this sample of anadromous trout despite absence of stocked domesticated trout could be...

  12. COMPUTER DESIGN OF PROCESSES OF MIGRATION OF ADMIXTURES IN NATURAL WATERS STREAMS

    OpenAIRE

    Savenko, V.; Bondarenko, L.

    2006-01-01

    In work new complex approach of research of processes of transfer of harmful admixtures is offered in natural streams, which is founded on the use of methods of three-dimensional computer design. Basic mathematical equalizations, description of software products, examples of numeral calculations, are resulted on the basis of the offered method

  13. Diffusion Decay Coefficient for Chloride Ions of Concrete Containing Mineral Admixtures

    Directory of Open Access Journals (Sweden)

    Jae-Im Park

    2016-01-01

    Full Text Available The diffusion coefficient for chloride ions and the diffusion decay coefficient for chloride ions are essential variables for a service life evaluation of concrete structures. They are influenced by water-binder ratio, exposure condition, curing temperature, cement type, and the type and use of mineral admixture. Mineral admixtures such as ground granulated blast furnace slag, fly ash, and silica fume have been increasingly used to improve resistance against chloride ions penetration in concrete structures built in an offshore environment. However, there is not enough measured data to identify the statistical properties of diffusion decay coefficient for chloride ions in concrete using mineral admixtures. This paper is aimed at evaluating the diffusion decay coefficient for chloride ions of concrete using ordinary Portland cement or blended cement. NT BUILD 492 method, an electrophoresis experiment, was used to measure the diffusion coefficient for chloride ions with ages. It was revealed from the test results that the diffusion decay coefficient for chloride ions was significantly influenced by W/B and the replacement ratio of mineral admixtures.

  14. Zinc content of commercial diluents widely used in drug admixtures prepared for intravenous infusion.

    Science.gov (United States)

    Desai, Narendra R; Shah, Syed M; Koczone, Julianna; Vencl-Joncic, Maja; Sisto, Christopher; Ludwig, Stephen A

    2007-01-01

    During ongoing quality improvement efforts with two Wyeth parenteral products, Protonix and Zosyn, we noted that dosing solutions prepared from the products yielded inconsistent results on the United States Pharmacopeia Chapter 788 test for subvisible particulates. This manuscript discusses variables that have a direct impact on intravenous products meeting compendial monograph specifications under conditions that are encountered in the clinical setting. The rubber stoppers of vials used for parenteral products, different parts of commercial admixture bags, and the tubing of the administration sets and devices contain residual amounts of metal ions, plasticizers, and other additives incorparated for specific functions. The transition metal ions, including zinc and copper, may leach into drug products during manufacture and during storage of dosing admixture bags prepared for infusion in hospital pharmacies or clinics. The metal ions may compromise the quality of the infusion admixture through catalytic drug degradation and/or generation of undesirable metal ion complexes, which may convert soluble drug molecules into insoluble particulates. To preserve the quality of the drug product, it is essential that metal ion leachables be controlled proactively during manufacture of the drug product; knowledge of metal ion contents in the commercial diluents use for reconstitution, admixture preparation, and flushing of the administration lines is also critical. PMID:23969523

  15. Population admixture, biological invasions and the balance between local adaptation and inbreeding depression

    NARCIS (Netherlands)

    Verhoeven, K.J.F.; Macel, M.; Wolfe, L.M.; Biere, A.

    2011-01-01

    When previously isolated populations meet and mix, the resulting admixed population can benefit from several genetic advantages, including increased genetic variation, the creation of novel genotypes and the masking of deleterious mutations. These admixture benefits are thought to play an important

  16. Phenomenological model of sintering of oxide nuclear fuel with doping admixtures

    Energy Technology Data Exchange (ETDEWEB)

    Baranov, V. G.; Devyatko, Yu. N.; Tenishev, A. V.; Khomyakov, O. V., E-mail: homaykov-o-v@rambler.ru [National Research Nuclear University MEPhI (Moscow Engineering Physics Institute) (Russian Federation)

    2015-12-15

    It is shown that a change in the linear dimension of compacted UO{sub 2} in the sintering process is associated with its plastic yielding under the action of the forces of residual stress and capillary forces. From the curves of sintering of a fuel with doping admixtures in various gaseous media, its rate of creep is reduced.

  17. Experimental study on durability improvement of fly ash concrete with durability improving admixture.

    Science.gov (United States)

    Quan, Hong-zhu; Kasami, Hideo

    2014-01-01

    In order to improve the durability of fly ash concrete, a series of experimental studies are carried out, where durability improving admixture is used to reduce drying shrinkage and improve freezing-thawing resistance. The effects of durability improving admixture, air content, water-binder ratio, and fly ash replacement ratio on the performance of fly ash concrete are discussed in this paper. The results show that by using durability improving admixture in nonair-entraining fly ash concrete, the compressive strength of fly ash concrete can be improved by 10%-20%, and the drying shrinkage is reduced by 60%. Carbonation resistance of concrete is roughly proportional to water-cement ratio regardless of water-binder ratio and fly ash replacement ratio. For the specimens cured in air for 2 weeks, the freezing-thawing resistance is improved. In addition, by making use of durability improving admixture, it is easier to control the air content and make fly ash concrete into nonair-entraining one. The quality of fly ash concrete is thereby optimized. PMID:25013870

  18. Experimental Study on Durability Improvement of Fly Ash Concrete with Durability Improving Admixture

    Directory of Open Access Journals (Sweden)

    Hong-zhu Quan

    2014-01-01

    Full Text Available In order to improve the durability of fly ash concrete, a series of experimental studies are carried out, where durability improving admixture is used to reduce drying shrinkage and improve freezing-thawing resistance. The effects of durability improving admixture, air content, water-binder ratio, and fly ash replacement ratio on the performance of fly ash concrete are discussed in this paper. The results show that by using durability improving admixture in nonair-entraining fly ash concrete, the compressive strength of fly ash concrete can be improved by 10%–20%, and the drying shrinkage is reduced by 60%. Carbonation resistance of concrete is roughly proportional to water-cement ratio regardless of water-binder ratio and fly ash replacement ratio. For the specimens cured in air for 2 weeks, the freezing-thawing resistance is improved. In addition, by making use of durability improving admixture, it is easier to control the air content and make fly ash concrete into nonair-entraining one. The quality of fly ash concrete is thereby optimized.

  19. Recycling of tailings from Korea Molybdenum Corporation as admixture for high-fluidity concrete.

    Science.gov (United States)

    Jung, Moon Young; Choi, Yun Wang; Jeong, Jae Gwon

    2011-01-01

    The main objective of this study is to develop an eco-friendly and a large recycling technique of flotation Tailings from korea (TK) from metal mines as construction materials such as admixtures for high-fluidity concrete (HFC). TK used in this study was obtained from the Korea Molybdenum Corporation in operation. TK was used as the alternative material to adjust flowability and viscosity of HFC in the form of powder agent which enables adjustment of concrete compressive strength. In this study, we have performed concrete rheological tests and concrete flowability tests to obtain the quality characteristics of TK for using as the admixture in producing HFC. The results indicated that the adequate mix ratio of cement to TK should be 8:2 (vol%). It is more effective to use the TK as admixture to control flowability, viscosity and strength of HFC than the normal concrete. It was found that TK could be recycled construction materials in bulk such as admixture for HFC, in terms of the economic and eco-friendly aspects. PMID:21113645

  20. What Causes Birth Order-Intelligence Patterns? The Admixture Hypothesis, Revived.

    Science.gov (United States)

    Rodgers, Joseph Lee

    2001-01-01

    Describes why birth order interests both parents and researchers, discussing what really causes apparent birth order effects on intelligence, examining problems with using cross-sectional intelligence data, and noting how to move beyond cross-sectional inferences. Explains the admixture hypothesis, which finds that family size is much more…

  1. Genetic analysis of ancestry, admixture and selection in Bolivian and Totonac populations of the New World

    Directory of Open Access Journals (Sweden)

    Watkins W

    2012-05-01

    Full Text Available Abstract Background Populations of the Americas were founded by early migrants from Asia, and some have experienced recent genetic admixture. To better characterize the native and non-native ancestry components in populations from the Americas, we analyzed 815,377 autosomal SNPs, mitochondrial hypervariable segments I and II, and 36 Y-chromosome STRs from 24 Mesoamerican Totonacs and 23 South American Bolivians. Results and Conclusions We analyzed common genomic regions from native Bolivian and Totonac populations to identify 324 highly predictive Native American ancestry informative markers (AIMs. As few as 40–50 of these AIMs perform nearly as well as large panels of random genome-wide SNPs for predicting and estimating Native American ancestry and admixture levels. These AIMs have greater New World vs. Old World specificity than previous AIMs sets. We identify highly-divergent New World SNPs that coincide with high-frequency haplotypes found at similar frequencies in all populations examined, including the HGDP Pima, Maya, Colombian, Karitiana, and Surui American populations. Some of these regions are potential candidates for positive selection. European admixture in the Bolivian sample is approximately 12%, though individual estimates range from 0–48%. We estimate that the admixture occurred ~360–384 years ago. Little evidence of European or African admixture was found in Totonac individuals. Bolivians with pre-Columbian mtDNA and Y-chromosome haplogroups had 5–30% autosomal European ancestry, demonstrating the limitations of Y-chromosome and mtDNA haplogroups and the need for autosomal ancestry informative markers for assessing ancestry in admixed populations.

  2. The Role of Recent Admixture in Forming the Contemporary West Eurasian Genomic Landscape

    Science.gov (United States)

    Busby, George B.J.; Hellenthal, Garrett; Montinaro, Francesco; Tofanelli, Sergio; Bulayeva, Kazima; Rudan, Igor; Zemunik, Tatijana; Hayward, Caroline; Toncheva, Draga; Karachanak-Yankova, Sena; Nesheva, Desislava; Anagnostou, Paolo; Cali, Francesco; Brisighelli, Francesca; Romano, Valentino; Lefranc, Gerard; Buresi, Catherine; Ben Chibani, Jemni; Haj-Khelil, Amel; Denden, Sabri; Ploski, Rafal; Krajewski, Pawel; Hervig, Tor; Moen, Torolf; Herrera, Rene J.; Wilson, James F.; Myers, Simon; Capelli, Cristian

    2015-01-01

    Summary Over the past few years, studies of DNA isolated from human fossils and archaeological remains have generated considerable novel insight into the history of our species. Several landmark papers have described the genomes of ancient humans across West Eurasia, demonstrating the presence of large-scale, dynamic population movements over the last 10,000 years, such that ancestry across present-day populations is likely to be a mixture of several ancient groups [1, 2, 3, 4, 5, 6, 7]. While these efforts are bringing the details of West Eurasian prehistory into increasing focus, studies aimed at understanding the processes behind the generation of the current West Eurasian genetic landscape have been limited by the number of populations sampled or have been either too regional or global in their outlook [8, 9, 10, 11]. Here, using recently described haplotype-based techniques [11], we present the results of a systematic survey of recent admixture history across Western Eurasia and show that admixture is a universal property across almost all groups. Admixture in all regions except North Western Europe involved the influx of genetic material from outside of West Eurasia, which we date to specific time periods. Within Northern, Western, and Central Europe, admixture tended to occur between local groups during the period 300 to 1200 CE. Comparisons of the genetic profiles of West Eurasians before and after admixture show that population movements within the last 1,500 years are likely to have maintained differentiation among groups. Our analysis provides a timeline of the gene flow events that have generated the contemporary genetic landscape of West Eurasia. PMID:26387712

  3. African Ancestry Analysis and Admixture Genetic Mapping for Proliferative Diabetic Retinopathy in African Americans

    Science.gov (United States)

    Tandon, Arti; Chen, Ching J.; Penman, Alan; Hancock, Heather; James, Maurice; Husain, Deeba; Andreoli, Christopher; Li, Xiaohui; Kuo, Jane Z.; Idowu, Omolola; Riche, Daniel; Papavasilieou, Evangelia; Brauner, Stacey; Smith, Sataria O.; Hoadley, Suzanne; Richardson, Cole; Kieser, Troy; Vazquez, Vanessa; Chi, Cheryl; Fernandez, Marlene; Harden, Maegan; Cotch, Mary Frances; Siscovick, David; Taylor, Herman A.; Wilson, James G.; Reich, David; Wong, Tien Y.; Klein, Ronald; Klein, Barbara E. K.; Rotter, Jerome I.; Patterson, Nick; Sobrin, Lucia

    2015-01-01

    Purpose. To examine the relationship between proportion of African ancestry (PAA) and proliferative diabetic retinopathy (PDR) and to identify genetic loci associated with PDR using admixture mapping in African Americans with type 2 diabetes (T2D). Methods. Between 1993 and 2013, 1440 participants enrolled in four different studies had fundus photographs graded using the Early Treatment Diabetic Retinopathy Study scale. Cases (n = 305) had PDR while controls (n = 1135) had nonproliferative diabetic retinopathy (DR) or no DR. Covariates included diabetes duration, hemoglobin A1C, systolic blood pressure, income, and education. Genotyping was performed on the Affymetrix platform. The association between PAA and PDR was evaluated using logistic regression. Genome-wide admixture scanning was performed using ANCESTRYMAP software. Results. In the univariate analysis, PDR was associated with increased PAA (odds ratio [OR] = 1.36, 95% confidence interval [CI] = 1.16–1.59, P = 0.0002). In multivariate regression adjusting for traditional DR risk factors, income and education, the association between PAA and PDR was attenuated and no longer significant (OR = 1.21, 95% CI = 0.59–2.47, P = 0.61). For the admixture analyses, the maximum genome-wide score was 1.44 on chromosome 1. Conclusions. In this largest study of PDR in African Americans with T2D to date, an association between PAA and PDR is not present after adjustment for clinical, demographic, and socioeconomic factors. No genome-wide significant locus (defined as having a locus-genome statistic > 5) was identified with admixture analysis. Further analyses with even larger sample sizes are needed to definitively assess if any admixture signal for DR is present. PMID:26098467

  4. Development of admixture mapping panels for African Americans from commercial high-density SNP arrays

    Directory of Open Access Journals (Sweden)

    Dunston Georgia M

    2010-07-01

    Full Text Available Abstract Background Admixture mapping is a powerful approach for identifying genetic variants involved in human disease that exploits the unique genomic structure in recently admixed populations. To use existing published panels of ancestry-informative markers (AIMs for admixture mapping, markers have to be genotyped de novo for each admixed study sample and samples representing the ancestral parental populations. The increased availability of dense marker data on commercial chips has made it feasible to develop panels wherein the markers need not be predetermined. Results We developed two panels of AIMs (~2,000 markers each based on the Affymetrix Genome-Wide Human SNP Array 6.0 for admixture mapping with African American samples. These two AIM panels had good map power that was higher than that of a denser panel of ~20,000 random markers as well as other published panels of AIMs. As a test case, we applied the panels in an admixture mapping study of hypertension in African Americans in the Washington, D.C. metropolitan area. Conclusions Developing marker panels for admixture mapping from existing genome-wide genotype data offers two major advantages: (1 no de novo genotyping needs to be done, thereby saving costs, and (2 markers can be filtered for various quality measures and replacement markers (to minimize gaps can be selected at no additional cost. Panels of carefully selected AIMs have two major advantages over panels of random markers: (1 the map power from sparser panels of AIMs is higher than that of ~10-fold denser panels of random markers, and (2 clusters can be labeled based on information from the parental populations. With current technology, chip-based genome-wide genotyping is less expensive than genotyping ~20,000 random markers. The major advantage of using random markers is the absence of ascertainment effects resulting from the process of selecting markers. The ability to develop marker panels informative for ancestry from

  5. Shrinkage and cracking behavior of high performance concretes containing chemical admixtures

    Institute of Scientific and Technical Information of China (English)

    亓萌; 李宗津; 马保国

    2002-01-01

    Modern concretes often incorporate several chemical admixtures to alter the properties of fresh or hardened concrete. In this work, the influences of three types of chemical admixtures, calcium nitrite inhibitor (CNI), retarder (D-17) and superplasticizer (W-19) on free shrinkage and restrained shrinkage cracking of high performance concrete were experimentally investigated. The test results showed that, with the same water to binder ratio (0.4), mixtures containing D-17 of 0.25 percent or higher ratio of W-19 (2.76 percent) all exhibited a reduction in free shrinkage and shrinkage cracking width. However, the incorporations of various ratios of CNI into mixtures led to an increase in free shrinkage and shrinkage cracking width as compared to control mixture. In order to study the influence of CNI, the microstructure of concrete mixture containing CNI were investigated by Mercury Intrusion Porosimetry as well as Scanning Electronic Microscopy(SEM) technique.

  6. Standard test method for initial screening of corrosion inhibiting admixtures for steel in concrete

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2007-01-01

    1.1 This test method covers a procedure for determining the effects of chemical admixtures on the corrosion of metals in concrete. This test method can be used to evaluate materials intended to inhibit chloride-induced corrosion of steel in concrete. It can also be used to evaluate the corrosivity of admixtures by themselves or in a chloride environment. This test is not applicable for emulsions. 1.2 &solely-SI-units; 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  7. The origin of early age expansions induced in cementitious materials containing shrinkage reducing admixtures

    International Nuclear Information System (INIS)

    Studies on the early-age shrinkage behavior of cement pastes, mortars, and concretes containing shrinkage reducing admixtures (SRAs) have indicated these mixtures frequently exhibit an expansion shortly after setting. While the magnitude of the expansion has been noted to be a function of the chemistry of the cement and the admixture dosage; the cause of the expansion is not clearly understood. This investigation uses measurements of autogenous deformation, X-ray diffraction, pore solution analysis, thermogravimetry, and scanning electron microscopy to study the early-age properties and describe the mechanism of the expansion in OPC pastes made with and without SRA. The composition of the pore solution indicates that the presence of the SRA increases the portlandite oversaturation level in solution which can result in higher crystallization stresses which could lead to an expansion. This observation is supported by deformation calculations for the systems examined.

  8. THEORY OF ACTIVE HITTINGS IS IN PROCESSES OF ELECTRO-COAGULATION THE ADMIXTURES IN WATER TECHNOLOGICAL ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    В.В. Березуцький

    2012-10-01

    Full Text Available  In the article theoretical bases of electro-coagulation of admixtures are examined in a water technological environment with the use of theory of the active hittings, which are based on the results of the executed researches and analysis of scientific information. Application of theory of the active hittings is in coagulation, provides high efficiency of process of extraction of admixtures from water environments during minimization of energy consumption and expenses of materials.

  9. Genome-wide Scan of 29,141 African Americans Finds No Evidence of Directional Selection since Admixture

    OpenAIRE

    Bhatia, Gaurav; Tandon, Arti; Patterson, Nick; Aldrich, Melinda C.; Ambrosone, Christine B.; Amos, Christopher; Bandera, Elisa V.; Berndt, Sonja I.; Bernstein, Leslie; Blot, William J.; Bock, Cathryn H.; Caporaso, Neil; Casey, Graham; Deming, Sandra L.; Diver, W. Ryan

    2014-01-01

    The extent of recent selection in admixed populations is currently an unresolved question. We scanned the genomes of 29,141 African Americans and failed to find any genome-wide-significant deviations in local ancestry, indicating no evidence of selection influencing ancestry after admixture. A recent analysis of data from 1,890 African Americans reported that there was evidence of selection in African Americans after their ancestors left Africa, both before and after admixture. Selection afte...

  10. Admixture analysis of stocked brown trout populations using mapped microsatellite DNA markers: indigenous trout persist in introgressed populations

    OpenAIRE

    Hansen, Michael M; Mensberg, Karen-Lise D.

    2009-01-01

    Admixture between wild and captive populations is an increasing concern in conservation biology. Understanding the extent of admixture and the processes involved requires identification of admixed and non-admixed individuals. This can be achieved by statistical methods employing Bayesian clustering, but resolution is low if genetic differentiation is weak. Here, we analyse stocked brown trout populations represented by historical (1943–1956) and contemporary (2000s) samples, where genetic dif...

  11. Stability investigation of total parenteral nutrition admixture prepared in a hospital pharmacy

    OpenAIRE

    Mirković Dušica; Antunović Mirjana; Putić Vesna; Aleksić Dragana

    2008-01-01

    Background/Aim. In the cases when nutrition of patients can not be orally nor enterally performed, parenteral nutrition is a method of the therapy that provides more successful and rapid recovery. In that way, hospitalization can be significantly shorter, healing costs reduced and mortality minimized. Total parenteral nutrition (TPN) admixtures are the most complex systems which contain amino acids, carbohydrates, lipid emulsion, macroelectrolytes (Na+, K+, Ca2+, Mg2+, Cl-, SO42-, PO43-), oli...

  12. Compatibility between base concrete made with different chemical admixtures and surface hardener

    OpenAIRE

    Pinheiro-Alves, M.ª Teresa; Sequeira, Ana Rita; Bettencourt Ribeiro, António

    2012-01-01

    Many cases of cracking and detachment of the concrete surface have appeared in concrete floors where surface hardeners were used in Portugal. The main causes for cracking and delamination of trowelled concrete pavements are several and it is essential to control bleeding and the time available to perform the finishing operations. Several base concretes were made with different chemical admixtures and one type of surface hardeners. The purpose of this study was evaluating the influence of the ...

  13. Quality assessment of total parenteral nutrition admixtures by the use of fractional factorial design

    Directory of Open Access Journals (Sweden)

    Mirković Dušica

    2013-01-01

    Full Text Available Background/Aim. Parenteral nutrition as a specific aspect of providing nutritients still remains a permanent topic of both theoretical and experimental research. Total parenteral nutrition (TPN admixtures have complex contents making difficult to maintain their stability. The most critical parameter is the diameter of a lipid droplet, i.e. droplet size distribution. It is recommended that droplet size should not be more than 5

  14. PREDICTION OF GLOBAL AND LOCAL SIMMENTAL AND RED HOLSTEIN FRIESIAN ADMIXTURE LEVELS IN SWISS FLECKVIEH CATTLE

    Directory of Open Access Journals (Sweden)

    Negar Khayatzadeh

    2015-09-01

    Full Text Available In this study we estimated levels of local ancestry for individuals of the Swiss Fleckvieh dairy cattle population. It is a composite breed descending from two pure breeds, Simmental (SIM and Red Holstein Friesian (RHF. Illumina BovineSNP50 Beadchip genotyping data for a total of 500 pure and admixed animals were used for the analysis. The global ancestries estimated by Hidden Markov model were 0.68 and 0.32 for RHF and SIM respectively. Local ancestry levels investigated along chromosomes 2, 3 and 13 indicated that there were some regions across the chromosomes exhibiting substantial fluctuations in admixture. On chromosome 2, in the range of 28 to 31, 41 to 46 and 54 to 56 Mb RHF ancestry is substantially higher than average (0.77-0.78. These regions on chromosome 2 are wide, indicating recent admixture. Along the segments on chromosome 2, many QTLs related to dairy, conformation, reproduction, health and carcass traits were found. We observed sharper excess in favour of SIM on chromosome 3, whereas different regions with excess of RHF and SIM were found out on Chromosome 13. At the first part of chromosome 13, an excess of RHF was observed. Moreover, in regions between 40 and 57 Mb excess of SIM, referred to recent admixture was detected. In respect of RHF chromosome segments in admixed animals, dairy, reproduction and health QTLs were found. In positions where more Simmental segments were detected, QTLs related to meat and carcass traits as well as udder health traits were found. In conclusion, the authors believe that estimation of local admixture levels in crossbred populations can add information to the composite breeds history of selection.

  15. Utilization of black liquor as concrete admixture and set retarder aid

    OpenAIRE

    Samar A. El-Mekkawi; Ibrahim M. Ismail; Mohammed M. El-Attar; Alaa A. Fahmy; Samia S. Mohammed

    2011-01-01

    The utilization of black liquor, produced by the pulp and paper industry in Egypt, as a workability aid and set retarder admixture has been investigated. This approach may help eliminate the environmentally polluting black liquor waste. It also provides a low cost by-product, which can be widely used in the construction industry. The properties of black liquor and its performance on concrete at two different ratios of water to cement have been studied. The results revealed that black liquor f...

  16. Semiconductor-metal transition in semiconductor melts with 3d metal admixtures

    International Nuclear Information System (INIS)

    Electrical conductivity and thermoelectric power measurements were performed for liquid semiconductor alloys Se0.5Te0.5 doped with 3d metals in a wide temperature range (up to 1600 K) under ambient pressures of argon gas (up to 30 MPa). Structure changes were studied by means of X-ray diffraction method. The 3d metal admixtures affect electrophysical properties and a temperature of the semiconductor-metal transition (SMT)

  17. Search for admixture of heavy neutrinos with masses between 5 and 55 keV

    OpenAIRE

    Markey, J.; Boehm, F.

    1985-01-01

    Using a magnetic spectrometer at a momentum resolution of 0.3%, we have studied the beta spectrum from 35S. We do not see evidence for the admixture of a heavy neutrino to the usual light (m~0) ν̃e accompanying beta decay, in the mass range between 5 and 50 keV, with a limit for the mixing strength of |U|2

  18. Profile of Intravenous Admixture Compatibility in the Intensive Care Unit (ICU) Patients

    OpenAIRE

    Sharly Dwijayanti; Sylvi Irawati; Eko Setiawan

    2016-01-01

    which may directly impact to the outcome of treatment to the Intensive Care Unit (ICU) patients. The objective of this study was to identify the profile of compatibility and incompatibility among IV admixtures given to the ICU patients. This observational research was conducted prospectively to the patients admitted in the ICU at a private hospital in Surabaya from October–December 2014. In this research, compatibility data of IV drug and its solution was compared with drug brochure and Handb...

  19. Lime-based repair mortars with water-repellent admixtures: laboratory durability assessment

    OpenAIRE

    Nunes, C.; Slížková, Z. (Zuzana)

    2015-01-01

    Conservation of architectural structures using lime binders is currently an important research topic aiming compatibility, durability and sustainability. In this study, lime (L) and lime-metakaolin (LM) mortars were prepared with the addition of water-repellent admixtures: linseed oil, stand oil and a silane based water-repellent. Experimental results demonstrate that oil imparts higher hydrophobicity to both L and LM mixtures. Durability was assessed through freeze-thaw and NaCl crystal...

  20. Intraspecific genetic admixture and the morphological diversification of an estuarine fish population complex.

    Science.gov (United States)

    Dodson, Julian J; Bourret, Audrey; Barrette, Marie France; Turgeon, Julie; Daigle, Gaétan; Legault, Michel; Lecomte, Frédéric

    2015-01-01

    The North-east American Rainbow smelt (Osmerus mordax) is composed of two glacial races first identified through the spatial distribution of two distinct mtDNA lineages. Contemporary breeding populations of smelt in the St. Lawrence estuary comprise contrasting mixtures of both lineages, suggesting that the two races came into secondary contact in this estuary. The overall objective of this study was to assess the role of intraspecific genetic admixture in the morphological diversification of the estuarine rainbow smelt population complex. The morphology of mixed-ancestry populations varied as a function of the relative contribution of the two races to estuarine populations, supporting the hypothesis of genetic admixture. Populations comprising both ancestral mtDNA races did not exhibit intermediate morphologies relative to pure populations but rather exhibited many traits that exceeded the parental trait values, consistent with the hypothesis of transgressive segregation. Evidence for genetic admixture at the level of the nuclear gene pool, however, provided only partial support for this hypothesis. Variation at nuclear AFLP markers revealed clear evidence of the two corresponding mtDNA glacial races. The admixture of the two races at the nuclear level is only pronounced in mixed-ancestry populations dominated by one of the mtDNA lineages, the same populations showing the greatest degree of morphological diversification and population structure. In contrast, mixed-ancestry populations dominated by the alternate mtDNA lineage showed little evidence of introgression of the nuclear genome, little morphological diversification and little contemporary population genetic structure. These results only partially support the hypothesis of transgressive segregation and may be the result of the differential effects of natural selection acting on admixed genomes from different sources. PMID:25856193

  1. Intraspecific Genetic Admixture and the Morphological Diversification of an Estuarine Fish Population Complex

    OpenAIRE

    Dodson, Julian J.; Bourret, Audrey; Barrette, Marie France; Turgeon, Julie; Daigle, Gaétan; Legault, Michel; Lecomte, Frédéric

    2015-01-01

    The North-east American Rainbow smelt (Osmerus mordax) is composed of two glacial races first identified through the spatial distribution of two distinct mtDNA lineages. Contemporary breeding populations of smelt in the St. Lawrence estuary comprise contrasting mixtures of both lineages, suggesting that the two races came into secondary contact in this estuary. The overall objective of this study was to assess the role of intraspecific genetic admixture in the morphological diversification of...

  2. Plant cover and water balance in gravel admixtures at an arid waste-burial site

    International Nuclear Information System (INIS)

    Isolation of radioactive waste buried in unsaturated zones will require long-term control of recharge and erosion. Soil covers control recharge at and sites by storing rainwater close enough to the surface to be removed by evapotranspiration. Surface layers of rock or gravel control erosion at sites with sparse vegetation, but can also alter plant habitat and cause recharge through interred waste. As an alternative, gravel mixed into the uppermost soil law may control erosion ever the king-term better than surface gravel layers. Gravel admixtures may also not influence plant establishment or sod water balance in waste-site covers. The interactive effects of gravel admixture concentration, vegetation, and precipitation on soil water content and plant cover were measured at the US Department of Energy's Hanford Site. Results support use of a combination of vegetation and gravel admixtures for erosion control. Vegetation seasonally depleted root zone water storage to about 6.5 volume % regardless of precipitation amount or the presence of gravel admixture amendments. In contrast, yearly increases in soil water storage as deep as 225 cm in plots without vegetation may be a leading indicator of recharge. The composition and abundance of vegetation changed over time and with precipitation amount, but was not influenced by gravel amendments. Seeded wheatgrasses [Agropyron sibericum Wilde and Agropyron dasystachyum (Hook.) Scribn.] established only when irrigated with twice average precipitation, but persisted after the irrigation ceased. Cheatgrass (Bromus tectorum L.) and Russian thistle (Salsola kali L.) colonized areas receiving both irrigation and ambient precipitation. Stands with wheatgrasses extracted water more rapidly and depleted soil water to lower levels than cheatgrass-dominated stands. Increases in gravel cover and near-surface gravel concentrations after 5 yr were evidence of the formation of a protective gravel veneer. 44 refs., 8 figs., 2 tabs

  3. Dissecting the genetic structure and admixture of four geographical Malay populations

    OpenAIRE

    Lian Deng; Boon-Peng Hoh; Dongsheng Lu; Woei-Yuh Saw; Rick Twee-Hee Ong; Anuradhani Kasturiratne; H Janaka de Silva; Bin Alwi Zilfalil; Norihiro Kato; Wickremasinghe, Ananda R; Yik-Ying Teo; Shuhua Xu

    2015-01-01

    The Malay people are an important ethnic composition in Southeast Asia, but their genetic make-up and population structure remain poorly studied. Here we conducted a genome-wide study of four geographical Malay populations: Peninsular Malaysian Malay (PMM), Singaporean Malay (SGM), Indonesian Malay (IDM) and Sri Lankan Malay (SLM). All the four Malay populations showed substantial admixture with multiple ancestries. We identified four major ancestral components in Malay populations: Austrones...

  4. Effect of water-repellent admixtures on the behaviour of aerial lime-based mortars

    OpenAIRE

    Izaguirre, A.; Lanas, J.; Alvarez, J I

    2009-01-01

    Two different anionic surfactants, sodium oleate and calcium stearate, commercialized as water repellents for cement-based mortars, were added to lime-based mortars in order to check whether they were improved by these admixtures. Different properties of lime-based mortars were evaluated: fresh state behaviour through water retention, air content and setting time, hardened state properties such as density, water absorption through capillarity, water vapour permeability, long-term compressive ...

  5. Reduction in nitrate leaching from a concrete waste form by using waterproofing admixture additions

    International Nuclear Information System (INIS)

    Admixture additions of active lime and tricalcium aluminate reduced leach rate about 20% during a seven-day test of a concrete waste form containing a nitrate bearing, aqueous waste. CaO was 5% more effective and, in SEM examination, appeared to hydrate to CaOH which expanded in the concrete pores and blocked water movement. Over time, this compound appeared to dissolve slowly in the water, and the barrier layer it produced slowly receded into the specimen interior

  6. Age of First Suicide Attempt in Men and Women: An Admixture Analysis

    OpenAIRE

    Hilario Blasco-Fontecilla; Alegria, Analucia A; David Delgado-Gomez; Teresa Legido-Gil; Jeronimo Saiz-Ruiz; Oquendo, Maria A; Enrique Baca-Garcia

    2012-01-01

    Objectives. To define different subgroups of suicide attempters according to age at onset of suicide attempts. Methods. Participants were 229 suicide attempters (147 females; 82 males) admitted to a general hospital in Madrid, Spain. We used admixture analysis to determine the best-fitting model for the age at onset of suicide attempts separated by sex. Results. The best fitted model for the age at onset of suicide attempts was a mixture of two gaussian distributions. Females showed an earlie...

  7. Properties of low drying-shrinkage concrete with shrinkage-reducing admixture

    International Nuclear Information System (INIS)

    Effects on drying shrinkage of concrete were tested by using cement, the limestone coarse aggregate and the shrinkage-reducing admixture. As the results, the drying shrinkage of concrete was realized below 400x10-6. By using this low drying-shrinkage concrete, to prevent cracking on concrete structure during the long service life and to secure the measuring accuracy of concrete structure related the accelerator are expected. (author)

  8. Tracing the origin of the east-west population admixture in the Altai region (Central Asia.

    Directory of Open Access Journals (Sweden)

    Mercedes González-Ruiz

    Full Text Available A recent discovery of Iron Age burials (Pazyryk culture in the Altai Mountains of Mongolia may shed light on the mode and tempo of the generation of the current genetic east-west population admixture in Central Asia. Studies on ancient mitochondrial DNA of this region suggest that the Altai Mountains played the role of a geographical barrier between West and East Eurasian lineages until the beginning of the Iron Age. After the 7th century BC, coinciding with Scythian expansion across the Eurasian steppes, a gradual influx of East Eurasian sequences in Western steppes is detected. However, the underlying events behind the genetic admixture in Altai during the Iron Age are still unresolved: 1 whether it was a result of migratory events (eastward firstly, westward secondly, or 2 whether it was a result of a local demographic expansion in a 'contact zone' between European and East Asian people. In the present work, we analyzed the mitochondrial DNA lineages in human remains from Bronze and Iron Age burials of Mongolian Altai. Here we present support to the hypothesis that the gene pool of Iron Age inhabitants of Mongolian Altai was similar to that of western Iron Age Altaians (Russia and Kazakhstan. Thus, this people not only shared the same culture (Pazyryk, but also shared the same genetic east-west population admixture. In turn, Pazyryks appear to have a similar gene pool that current Altaians. Our results further show that Iron Age Altaians displayed mitochondrial lineages already present around Altai region before the Iron Age. This would provide support for a demographic expansion of local people of Altai instead of westward or eastward migratory events, as the demographic event behind the high population genetic admixture and diversity in Central Asia.

  9. Chemical stability of an admixture combining ziconotide and bupivacaine during simulated intrathecal administration.

    Science.gov (United States)

    Shields, David; Montenegro, Rick; Aclan, Jennifer

    2007-10-01

    Objective.  To determine the stability of an admixture combining ziconotide with bupivacaine hydrochloride during simulated intrathecal infusion under laboratory conditions at 37°. Materials and Methods.  An admixture containing ziconotide (25 µg/mL) and bupivacaine hydrochloride (5 mg/mL) was stored in SynchroMed® II pumps at 37° and in control vials at either 37° or 5°. Using high-performance liquid chromatography, drug concentrations were determined from samples obtained at varying intervals during the 30-day study. Results.  After 30 days, pump ziconotide and bupivacaine hydrochloride concentrations measured an average of 86.9% and 99.4% of their initial concentrations, respectively. Control vials displayed similar degradation rates for both drugs. Statistical evaluation of the ziconotide 95% confidence interval indicated that the ziconotide concentration would meet or exceed 90% and 80% of initial concentration for 22 days and 45 days, respectively. Conclusions.  An admixture containing 25 µg/mL ziconotide and 5 mg/mL bupivacaine hydrochloride was 90% stable for 22 days and 80% stable for 45 days (extrapolated) in SynchroMed® II infusion pumps. PMID:22150945

  10. Rate of decay in admixture linkage disequilibrium and its implication in gene mapping

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Modeling linkage disequilibria (LD) between genes usually observed in admixed natural populations has been shown an effective approach in high-resolution mapping of disease genes in humans. A prerequisite to obtain accurate estimation of recombination fraction between genes at a marker locus and the disease locus using the approach is a reliable prediction of the proportion of the admixture populations. The present study suggested the use of gene frequencies to predict the estimate of the admixture propor-tion based on the observation that the gene frequencies are much more stable quantities than the haplotype frequencies over evolution of the population. In this paper, we advanced the theory and methods by which the decay rate of nonlinear term of LD in admixed population may be used to estimate the recombination fraction between the genes. Theoretical analysis and simulation study indicate that, the larger the difference of gene frequencies between parental populations and the more closely the admixture proportion approaches 0.5, the more important the nonlinear term of the LD in the admixed population, and hence the more informative such admixed populations in the high-resolution gene mapping practice.

  11. Effect of Chemical Admixtures on the Engineering Properties of Tropical Peat Soils

    Directory of Open Access Journals (Sweden)

    Bujang B.K. Huat

    2005-01-01

    Full Text Available This research describes a study on the effect of chemical (cement and lime admixtures on the index and engineering properties (compaction and unconfined strength of tropical peat soils. The ordinary Portland cement and hydrated lime were used. The amounts cement and lime added to the peat soil sample, as a percentage of the dry soil mass was in the range of 5-15% and 5-25%, respectively. The results of the study show that the addition of the chemical admixture, cement and lime, can improve the engineering properties of tropical peat soils. The soil liquid limit is found to decrease with an increase in the cement and lime content. The soil maximum dry density is found to increase while the optimum water content is found to decrease with an increase in the cement and lime content. The unconfined compressive strength of the soil is found to increase significantly with increase in cement and lime content, especially after a long curing period. However it is also found that higher organic content of the soil negate the positive effect of the cement and lime in altering (improving the mechanical properties of the soil. When comparing the performance of the cement and lime as a chemical admixture for the tropical peat soil, the ordinary Portland cement appears to perform better than the hydrated lime.

  12. Effects of lithium nitrate admixture on early-age cement hydration

    International Nuclear Information System (INIS)

    Although the benefits of lithium admixtures for mitigation of alkali-silica reaction (ASR) have been well documented, the potential ancillary effects of lithium compounds on cement and concrete remain largely uncharacterized. To examine the effects of the most common lithium admixture - lithium nitrate - on early-age behavior, the admixture was introduced at dosages of 0% to 400% of the recommended dosage to six cements of varying composition and to a cement-fly ash blend. Behavior was examined by isothermal calorimetry and measurements of chemical shrinkage, autogenous shrinkage, and setting time. Results indicate that lithium nitrate accelerates the early hydration of most cements but may retard hydration after 24 h. In the lowest alkali cement tested, set times were shortened in the presence of lithium nitrate by 15-22%. Higher dosages appeared to increase autogenous shrinkage after 40 days. The replacement of cement by Class F fly ash at 20% by weight appeared to diminish the early acceleration effects, but later hydration retardation and autogenous shrinkage were still observed

  13. Study on Strength and Microstructure of Cement-Based Materials Containing Combination Mineral Admixtures

    Directory of Open Access Journals (Sweden)

    Meijuan Rao

    2016-01-01

    Full Text Available The compressive strength of complex binders containing two or three blended mineral admixtures in terms of glass powder (GP, limestone powder (LP, and steel slag powder (SP was determined by a battery solution type compressive testing machine. The morphology and microstructure characteristics of complex binder hydration products were also studied by microscopic analysis methods, such as XRD, TG-DTA, and SEM. The mechanical properties of the cement-based materials were analyzed to reveal the most appropriate mineral admixture type and content. The early sample strength development with GP was very slow, but it rapidly grew at later stages. The micro aggregate effect and pozzolanic reaction mutually occurred in the mineral admixture. In the early stage, the micro aggregate effect reduced paste porosity and the small particles connected with the cement hydration products to enhance its strength. In the later stage, the pozzolanic reaction of some components in the complex powder occurred and consumed part of the calcium hydroxide to form C-S-H gel, thus improving the hydration environment. Also, the produced C-S-H gel made the structure more compact, which improved the structure’s strength.

  14. Chemical stability of ziconotide-clonidine hydrochloride admixtures with and without morphine sulfate during simulated intrathecal administration.

    Science.gov (United States)

    Shields, David; Montenegro, Rick

    2007-10-01

    Objective.  To determine the stability of ziconotide-clonidine hydrochloride admixtures with and without morphine sulfate during simulated intrathecal infusion under laboratory conditions at 37°. Materials and Methods.  Admixtures of ziconotide (25 µg/mL) and clonidine hydrochloride (2 mg/mL) with and without morphine sulfate (35 mg/mL) were stored in Medtronic SynchroMed® II pumps at 37°. Pumps were sampled immediately after filling and at four additional time points over the course of 28 (ziconotide-clonidine hydrochloride admixture) or 20 (ziconotide-clonidine hydrochloride-morphine sulfate admixture) days. Drug concentrations were determined using high-performance liquid chromatography. Results.  Ziconotide concentration exceeded 97% of initial at all time points when combined with clonidine alone; statistical evaluation indicated that both ziconotide and clonidine concentrations would remain above 90% of initial for more than 60 days. When compounded with both clonidine and morphine, ziconotide and clonidine concentrations declined; statistical evaluation indicated that the ziconotide concentration was 70% of initial after 20 days, and that clonidine would remain 90% stable for 42 days. Morphine was stable in the presence of ziconotide and clonidine. Conclusions.  A ziconotide-clonidine admixture was 90% stable for 60 days (extrapolated), and a ziconotide-clonidine-morphine admixture was 70% stable for 20 days. PMID:22150946

  15. Chemical, Mechanical, and Durability Properties of Concrete with Local Mineral Admixtures under Sulfate Environment in Northwest China

    Directory of Open Access Journals (Sweden)

    Qingke Nie

    2014-05-01

    Full Text Available Over the vast Northwest China, arid desert contains high concentrations of sulfate, chloride, and other chemicals in the ground water, which poses serious challenges to infrastructure construction that routinely utilizes portland cement concrete. Rapid industrialization in the region has been generating huge amounts of mineral admixtures, such as fly ash and slags from energy and metallurgical industries. These industrial by-products would turn into waste materials if not utilized in time. The present study evaluated the suitability of utilizing local mineral admixtures in significant quantities for producing quality concrete mixtures that can withstand the harsh chemical environment without compromising the essential mechanical properties. Comprehensive chemical, mechanical, and durability tests were conducted in the laboratory to characterize the properties of the local cementitious mineral admixtures, cement mortar and portland cement concrete mixtures containing these admixtures. The results from this study indicated that the sulfate resistance of concrete was effectively improved by adding local class F fly ash and slag, or by applying sulfate resistance cement to the mixtures. It is noteworthy that concrete containing local mineral admixtures exhibited much lower permeability (in terms of chloride ion penetration than ordinary portland cement concrete while retaining the same mechanical properties; whereas concrete mixtures made with sulfate resistance cement had significantly reduced strength and much increased chloride penetration comparing to the other mixtures. Hence, the use of local mineral admixtures in Northwest China in concrete mixtures would be beneficial to the performance of concrete, as well as to the protection of environment.

  16. Admixture mapping of end stage kidney disease genetic susceptibility using estimated mutual information ancestry informative markers

    Directory of Open Access Journals (Sweden)

    Geiger Dan

    2010-10-01

    Full Text Available Abstract Background The question of a genetic contribution to the higher prevalence and incidence of end stage kidney disease (ESKD among African Americans (AA remained unresolved, until recent findings using admixture mapping pointed to the association of a genomic locus on chromosome 22 with this disease phenotype. In the current study we utilize this example to demonstrate the utility of applying a multi-step admixture mapping approach. Methods A multi-step case only admixture mapping study, consisted of the following steps was designed: 1 Assembly of the sample dataset (ESKD AA; 2 Design of the estimated mutual information ancestry informative markers (n = 2016 screening panel 3; Genotyping the sample set whose size was determined by a power analysis (n = 576 appropriate for the initial screening panel; 4 Inference of local ancestry for each individual and identification of regions with increased AA ancestry using two different ancestry inference statistical approaches; 5 Enrichment of the initial screening panel; 6 Power analysis of the enriched panel 7 Genotyping of additional samples. 8 Re-analysis of the genotyping results to identify a genetic risk locus. Results The initial screening phase yielded a significant peak using the ADMIXMAP ancestry inference program applying case only statistics. Subgroup analysis of 299 ESKD patients with no history of diabetes yielded peaks using both the ANCESTRYMAP and ADMIXMAP ancestry inference programs. The significant peak was found on chromosome 22. Genotyping of additional ancestry informative markers on chromosome 22 that took into account linkage disequilibrium in the ancestral populations, and the addition of samples increased the statistical significance of the finding. Conclusions A multi-step admixture mapping analysis of AA ESKD patients replicated the finding of a candidate risk locus on chromosome 22, contributing to the heightened susceptibility of African Americans to develop non

  17. Influence of Air Temperature on the Performance of Different Water-Reducing Admixtures with Respect to the Properties of Fresh and Hardened Mortar

    OpenAIRE

    Wilson Ricardo Leal Silva; Luiz Roberto Prudêncio; Alexandre Lima Oliveira; Gabriela Damo; Eduardo Tochetto

    2010-01-01

    The performance of water-reducing admixtures used in concrete is affected by the weather conditions to which the concrete mixture is exposed. The most used WRAs are lignosulfonate, naphthalene, and polycarboxylate. However, they react differently to weather conditions, especially to air temperature. Therefore, it can be useful to evaluate how temperature affects admixture performance. In this study, the performance of three admixtures (naphthalene, lignosulfonate, and polycarboxylate) was eva...

  18. Effectiveness of shrinkage-reducing admixtures on Portland pozzolan cement concrete

    Directory of Open Access Journals (Sweden)

    Videla, C.

    2005-06-01

    Full Text Available Drying shrinkage causes tensile stress in restrained concrete members. Since all structural elements are subject to some degree of restraint, drying shrinkage is regarded to be one of the main causes of concrete cracking. The purpose of the present study was to evaluate the effectiveness of SRA in reducing drying shrinkage strain in Portland pozzolan cement concrete. The major variables examined included slump, admixture type and dose, and specimen size. The measured results indicate that any of the admixtures used in the study significantly reduced shrinkage. Concrete manufactured with shrinkage reducing admixtures shrank an average of 43% less than concrete without admixtures. As a rule, the higher the dose of admixture, the higher was its shrinkage reduction performance. The experimental results were compared to the shrinkage strain estimated with the ACI 209, CEB MC 90, B3, GL 2000, Sakata 1993 and Sakata 2001 models. Although none of these models was observed to accurately describe the behaviour of Portland pozzolan cement concrete with shrinkage reducing admixtures, the Sakata 2001 model, with a weighted coefficient of variation of under 30%, may be regarded to be roughly adequate.

    La retracción por secado es un fenómeno intrínseco del hormigón que produce tensiones de tracción en elementos restringidos de hormigón. Puesto que todos los elementos presentan algún grado de retracción, se considera a la retracción por secado como una de las principales causas de agrietamiento en proyectos de construcción en hormigón. Por lo tanto, el objetivo de esta investigación fue evaluar la efectividad de los aditivos reductores de retracción (SRA en hormigones fabricados con cemento Portland puzolánico. Las variables principales estudiadas incluyen el asentamiento de cono de Abrams, marca y dosis de aditivo reductor de retracción, y tamaño de espécimen de hormigón. Los resultados obtenidos permiten concluir que el uso de

  19. Application of a polycarboxylate ether admixture in RCC dam construction[ACI SP-239

    Energy Technology Data Exchange (ETDEWEB)

    Asmus, S.M.F.; Christensen, B.J.; Varley, N.J. [BASF Construction Chemicals Asia Pacific, Shanghai (China)

    2006-07-01

    Chemical admixtures are used in dam construction to improve plasticity of the dry materials mixture over time. Roller compacted concrete (RCC) has been used on many dam projects in China. However, the use of RCC has frequently resulted in water reduction problems. This paper provided details of an admixture based on polycarboxylate ether (PCE) which was developed to improve the quality of RCC constructions at the JinHong dam in China. Use of the polymer at the JinHong dam resulted in a vibration sensitive concrete that was sustained over time. Under identical mix-design and compaction conditions in the laboratory, specific gravity of the RCC was increased from 2417 kg/m{sup 3} to 2463 kg/m{sup 3}. The high specific gravity of the material resulted in satisfactory strength data from the dam project. The key-ratio of the splitting tensile strength versus compressive strength was higher than 8 per cent in all cases. A key advantage of the tailored PCE-RCC was the short Vebe times sustained over elapsed time in the RCC. Without additional compaction or vibration efforts, the specific density of RCC was better than conventional admixture technologies. The reduced viscosity provided cement paste films which formed on the surface of each layer of the RCC, which resulted in better bonding between the layers. It was concluded that the new PCE polymer is compatible with alternative retarder systems, which contributes to more extensive setting times under strict hydration regimes. 7 refs., 4 tabs., 4 figs.

  20. Effect of poly car boxy late admixtures on portland cement paste setting and rheological behaviour

    Directory of Open Access Journals (Sweden)

    Puertas, F.

    2005-03-01

    Full Text Available The objective of the work was to determine the effects of polycarboxilated-type admixture on the setting times and the rheological properties of different types of cements including CEM I 42.5 R, CEM Il/B-V 42.5 N and CEM III/B 32.5 N, defined according to the UNE EN 197-1:2000 standard. The results show that there is a lineal relationship between the initial setting times and the admixture dosage. Mathematical equations that model this behaviour for each of the cements have been determined. The data obtained from the minislump test and from the rheological parameters determined using the rheometer (plastic viscosity and yield stress point to similar conclusions. It was also verified that the workability effect of the polycarboxilate admixture is most intense for blended cements.

    El objetivo de este trabajo ha sido estudiar el efecto de la dosificación de un aditivo basado en policarboxilatos sobre el inicio de tiempo de fraguado y las propiedades reo lógicas en pastas de diferentes tipos de cemento (CEM 142.5 R, CEM 11/ B-V42.5 NYCEMIII/B 32.5 N-Norma EN 197-1:2000. existe una relación lineal entre el inicio del fraguado y la dosificación del aditivo, se han determinado las ecuaciones matemáticas que describen este comportamiento para cada cemento, los resultados obtenidos sobre la fluidez de la pasta en el ensayo del "minislump" coinciden con la evolución de los valores de los parámetros reológicos (esfuerzo de cizalladura y viscosidad plástica determinados a través de un reómetro. el efecto fluidificante del aditivo superplastificante basado en policarboxilatos es mucho más marcado en cementos que contienen adiciones.

  1. Variation in genetic admixture and population structure among Latinos: the Los Angeles Latino eye study (LALES

    Directory of Open Access Journals (Sweden)

    Le Marchand Loic

    2009-11-01

    Full Text Available Abstract Background Population structure and admixture have strong confounding effects on genetic association studies. Discordant frequencies for age-related macular degeneration (AMD risk alleles and for AMD incidence and prevalence rates are reported across different ethnic groups. We examined the genomic ancestry characterizing 538 Latinos drawn from the Los Angeles Latino Eye Study [LALES] as part of an ongoing AMD-association study. To help assess the degree of Native American ancestry inherited by Latino populations we sampled 25 Mayans and 5 Mexican Indians collected through Coriell's Institute. Levels of European, Asian, and African descent in Latinos were inferred through the USC Multiethnic Panel (USC MEP, formed from a sample from the Multiethnic Cohort (MEC study, the Yoruba African samples from HapMap II, the Singapore Chinese Health Study, and a prospective cohort from Shanghai, China. A total of 233 ancestry informative markers were genotyped for 538 LALES Latinos, 30 Native Americans, and 355 USC MEP individuals (African Americans, Japanese, Chinese, European Americans, Latinos, and Native Hawaiians. Sensitivity of ancestry estimates to relative sample size was considered. Results We detected strong evidence for recent population admixture in LALES Latinos. Gradients of increasing Native American background and of correspondingly decreasing European ancestry were observed as a function of birth origin from North to South. The strongest excess of homozygosity, a reflection of recent population admixture, was observed in non-US born Latinos that recently populated the US. A set of 42 SNPs especially informative for distinguishing between Native Americans and Europeans were identified. Conclusion These findings reflect the historic migration patterns of Native Americans and suggest that while the 'Latino' label is used to categorize the entire population, there exists a strong degree of heterogeneity within that population, and that

  2. Polar and brown bear genomes reveal ancient admixture and demographic footprints of past climate change

    Science.gov (United States)

    Miller, Webb; Schuster, Stephan C.; Welch, Andreanna J.; Ratan, Aakrosh; Bedoya-Reina, Oscar C.; Zhao, Fangqing; Kim, Hie Lim; Burhans, Richard C.; Drautz, Daniela I.; Wittekindt, Nicola E.; Tomsho, Lynn P.; Ibarra-Laclette, Enrique; Herrera-Estrella, Luis; Peacock, Elizabeth; Farley, Sean; Sage, George K.; Rode, Karyn; Obbard, Martyn E.; Montiel, Rafael; Bachmann, Lutz; Ingólfsson, Ólafur; Aars, Jon; Mailund, Thomas; Wiig, Øystein; Talbot, Sandra L.; Lindqvist, Charlotte

    2012-01-01

    Polar bears (PBs) are superbly adapted to the extreme Arctic environment and have become emblematic of the threat to biodiversity from global climate change. Their divergence from the lower-latitude brown bear provides a textbook example of rapid evolution of distinct phenotypes. However, limited mitochondrial and nuclear DNA evidence conflicts in the timing of PB origin as well as placement of the species within versus sister to the brown bear lineage. We gathered extensive genomic sequence data from contemporary polar, brown, and American black bear samples, in addition to a 130,000- to 110,000-y old PB, to examine this problem from a genome-wide perspective. Nuclear DNA markers reflect a species tree consistent with expectation, showing polar and brown bears to be sister species. However, for the enigmatic brown bears native to Alaska's Alexander Archipelago, we estimate that not only their mitochondrial genome, but also 5–10% of their nuclear genome, is most closely related to PBs, indicating ancient admixture between the two species. Explicit admixture analyses are consistent with ancient splits among PBs, brown bears and black bears that were later followed by occasional admixture. We also provide paleodemographic estimates that suggest bear evolution has tracked key climate events, and that PB in particular experienced a prolonged and dramatic decline in its effective population size during the last ca. 500,000 years. We demonstrate that brown bears and PBs have had sufficiently independent evolutionary histories over the last 4–5 million years to leave imprints in the PB nuclear genome that likely are associated with ecological adaptation to the Arctic environment.

  3. Rectification cleaning AsCl3 from the admixture of oxygen

    Directory of Open Access Journals (Sweden)

    Maznitska O. V.

    2008-06-01

    Full Text Available The process of the rectification cleaning of three-chlorous arsenic from the admixtures of products of his hydrolysis in the atmosphere of chlorous hydrogen has been considered in the article. Dependence of coefficient of relative volatility a three-chlorous arsenic from his concentration in muriatic solution is explored. The conduct of coefficient of relative volatility with concentrations of HCl and AsCl3 is compared. Saving of equalization of balance and equalization of working curve of column at such conduct of process of rectification is shown.

  4. An experimental study of the combustion characteristics of groundnut shell and waste paper admixture briquettes

    OpenAIRE

    O.A Oyelaran; B.O. Bolaji; M.A. Waheed; Adekunle, M.F.

    2015-01-01

    The study was undertaken to assess the heat released of briquettes produced from waste paper and groundnut shell admixture in five mixing ratios (90:10; 80:20; 70:30; 60:40; and 50:50). The briquettes were prepared on an existing motorized briquetting machine. The suitability of briquetted fuel as domestic fuel was studied in terms of flame propagation, afterglow, calorific value, and utilized heat, after sun drying the prepared briquettes for nineteen (19) days. The results of propagation ra...

  5. Compost admixture impact study on water infiltration depth, water front advance and recession in irrigated environment

    International Nuclear Information System (INIS)

    Water is an important life supporting resource and is essential for sustainable food production. Its continued decrease has diverted the attention of researchers to find new ways of efficient irrigation management. Decomposed bio-solids (for example leaves, crop residue, animal waste, municipal solid waste) form the compost and provide friendly environment for enhancing crop production. The present study investigates the effects of compost admixture on water infiltration depth, water advance and recession phase of irrigation event in the field having loamy sand texture. Compost from two sources was used. There were nine experimental plots with 3.5 m width and 45 m length. Compost at the rate of 5 % was incorporated up to a depth of 3 cm in six plots (3 plots of each compost source) and in the remaining three plots no compost was applied. The field was irrigated twice. The results revealed that by using 5% compost admixture by weight the advance time reduced by 23.96% and 26.83 % for first and second irrigation, respectively compared to non compost admixture plots. Results revealed that by using 5 % compost up to 3 cm mixing depth the water infiltration depth decreased 42.97 % at head side of the field and 10.37 % at tail side of field during first irrigation, during second irrigation the water infiltration depth decreased 48.67 % at upper end of the field and 11.28 % at lower end of the field. The significant decrease in water infiltration depth at head side gives uniformity in water infiltration depth along the length of field. The faster movement of the water front with the application of compost admixture reduces the difference in intake opportunity times between the head and far end of the field, thus it improves the performance of the irrigation system. Reduction in the applied water volume to the tone of 23.96% during first irrigation and 26.83% during second irrigation, further supports this improvement in irrigation performance, considering on the advance

  6. An investigation of admixture in an Australian Aboriginal Y-chromosome STR database.

    Science.gov (United States)

    Taylor, Duncan; Nagle, Nano; Ballantyne, Kaye N; van Oorschot, Roland A H; Wilcox, Stephen; Henry, Julianne; Turakulov, Rust; Mitchell, R John

    2012-09-01

    Y-chromosome specific STR profiling is increasingly used in forensic casework. However, the strong geographic clustering of Y haplogroups can lead to large differences in Y-STR haplotype frequencies between different ethnicities, which may have an impact on database composition in admixed populations. Aboriginal people have inhabited Australia for over 40,000 years and until ∼300 years ago they lived in almost complete isolation. Since the late 18th century Australia has experienced massive immigration, mainly from Europe, although in recent times from more widespread origins. This colonisation resulted in highly asymmetrical admixture between the immigrants and the indigenes. A State jurisdiction within Australia has created an Aboriginal Y-STR database in which assignment of ethnicity was by self-declaration. This criterion means that some males who identify culturally as members of a particular ethnic group may have a Y haplogroup characteristic of another ethnic group, as a result of admixture in their paternal line. As this may be frequent in Australia, an examination of the extent of genetic admixture within the database was performed. A Y haplogroup predictor program was first used to identify Y haplotypes that could be assigned to a European haplogroup. Of the 757 males (589 unique haplotypes), 445 (58.8%) were identified as European (354 haplotypes). The 312 non-assigned males (235 haplotypes) were then typed, in a hierarchical fashion, with a Y-SNP panel that detected the major Y haplogroups, C-S, as well as the Aboriginal subgroup of C, C4. Among these 96 males were found to have non-Aboriginal haplogroups. In total, ∼70% of Y chromosomes in the Aboriginal database could be classed as non-indigenous, with only 169 (129 unique haplotypes) or 22% of the total being associated with haplogroups denoting Aboriginal ancestry, C4 and K* or more correctly K(xL,M,N,O,P,Q,R,S). The relative frequencies of these indigenous haplogroups in South Australia (S

  7. No clear effect of admixture betweent two european invading outbreaks of Diabrotica virgifera virgifera in natura

    OpenAIRE

    Cavigliasso, Fanny; Mallez, Sophie,; Spencer, Joseph; Guillemaud, Thomas

    2014-01-01

    In this study, we challenged the hypothesis that admixture may have had a positive impact in the context of the European invasion of the western corn rootworm (WCR), Diabrotica virgifera virgifera, LeConte. This beetle was introduced in Europe from the USA several times since the 1980’s. The multiple introductions of this major pest of cultivated corn led to the formation of two major outbreaks in North Western (NW) Italy and in Central and South Eastern (CSE) Europe that eventually merged in...

  8. A Comparative Study on Compressive and Flexural Strength of Concrete Containing Different Admixtures as Partial Replacement of Cement

    Directory of Open Access Journals (Sweden)

    Apoorv Singh

    2014-09-01

    Full Text Available Concrete is the most widely used material in the world today. This paper is about the comparative study of the flexural strength and compressive strength of concrete when different admixtures are used as partial replacement of cement in the concrete mix. The mineral admixtures that are used here are Silica Fume, Rice Husk Ash and Iron slag as partial replacement of cement. All these materials are industrial waste products and are abundantly available nowadays. These materials have high silica content and pozzolanic properties and can be effectively used as a replacement of cement during the formation of High Performance Concrete. Compressive and Flexural strength are the two most important characteristic of concrete and are calculated for the hardened concrete to analyze the load bearing capacity for design purposes. Thus for the effective judgment of type of mineral admixtures to be used a comparative study is very useful.

  9. Alkali-activated complex binders from class C fly ash and Ca-containing admixtures.

    Science.gov (United States)

    Guo, Xiaolu; Shi, Huisheng; Chen, Liming; Dick, Warren A

    2010-01-15

    Processes that maximize utilization of industrial solid wastes are greatly needed. Sodium hydroxide and sodium silicate solution were used to create alkali-activated complex binders (AACBs) from class C fly ash (CFA) and other Ca-containing admixtures including Portland cement (PC), flue gas desulfurization gypsum (FGDG), and water treatment residual (WTR). Specimens made only from CFA (CFA100), or the same fly ash mixed with 40 wt% PC (CFA60-PC40), with 10 wt% FGDG (CFA90-FGDG10), or with 10 wt% WTR (CFA90-WTR10) had better mechanical performance compared to binders using other mix ratios. The maximum compressive strength of specimens reached 80.0 MPa. Geopolymeric gel, sodium polysilicate zeolite, and hydrated products coexist when AACB reactions occur. Ca from CFA, PC, and WTR precipitated as Ca(OH)(2), bonded in geopolymers to obtain charge balance, or reacted with dissolved silicate and aluminate species to form calcium silicate hydrate (C-S-H) gel. However, Ca from FGDG probably reacted with dissolved silicate and aluminate species to form ettringite. Utilization of CFA and Ca-containing admixtures in AACB is feasible. These binders may be widely utilized in various applications such as in building materials and for solidification/stabilization of other wastes, thus making the wastes more environmentally benign. PMID:19767143

  10. Genetic admixture history of Eastern Indonesia as revealed by Y-chromosome and mitochondrial DNA analysis.

    Science.gov (United States)

    Mona, Stefano; Grunz, Katharina E; Brauer, Silke; Pakendorf, Brigitte; Castrì, Loredana; Sudoyo, Herawati; Marzuki, Sangkot; Barnes, Robert H; Schmidtke, Jörg; Stoneking, Mark; Kayser, Manfred

    2009-08-01

    Eastern Indonesia possesses more linguistic diversity than any other region in Southeast Asia, with both Austronesian (AN) languages that are of East Asian origin, as well as non-Austronesian (NAN) languages of likely Melanesian origin. Here, we investigated the genetic history of human populations from seven eastern Indonesian islands, including AN and NAN speakers, as well as the relationship between languages and genes, by means of nonrecombining Y-chromosomal (NRY) and mitochondrial DNA (mtDNA) analysis. We found that the eastern Indonesian gene pool consists of East Asian as well as Melanesian components, as might be expected based on linguistic evidence, but also harbors putative indigenous eastern Indonesian signatures that perhaps reflect the initial occupation of the Wallacea by aboriginal hunter-gatherers already in Palaeolithic times. Furthermore, both NRY and mtDNA data showed a complete lack of correlation between linguistic and genetic relationships, most likely reflecting genetic admixture and/or language shift. In addition, we noted a small fraction of the NRY and mtDNA data shared between eastern Indonesians and Australian Aborigines likely reflecting an ancient link between Asia and Australia. Our data thus provide insights into the complex genetic ancestry history of eastern Indonesian islanders characterized by several admixture episodes and demonstrate a clear example of the lack of the often-assumed correlation between the genes and languages of human populations. PMID:19414523

  11. Improvement Of Sub-Grade Soil Properties Using Admixture Quarry Dust And Woven Geo-Textile

    Directory of Open Access Journals (Sweden)

    G. Priya Vasudha

    2015-08-01

    Full Text Available Abstract The important factor for design and construction of pavement is the behavior of underlying sub-grade. Large deformations in the sub-grade will lead to a continuous deterioration of the paved surface. As the sub-grade soil is too weak to bear the load engineering solutions such as geo reinforcement using geo-synthetics are additives which are earlier used in sub-grade improvement and such experimental study is carried by pervious authors. This paper deals with the sub-grade improvement using geo-textile as a reinforcement sheet and quarry dust as admixtures. In order to increase the strength of the sub-grade the quarry dust is varied with different percentages i.e. 0 5 10 15 20 and 25. In this study Proctors compaction tests and CBR soaked and unsoaked tests are conducted on locally available soil with reinforced material and with admixture. For this study it is identified that the engineering properties of the soil is improved in all conditions. The soil with quarry dust at optimum value is 20 has CBR soaked value is obtained 6.83 and unsoaked value is obtained 7.02 is increased when compared with conventionally soil. The soil quarry dust at optimum value is at 20 and Geo-textile has CBR soaked value is 6.59 and unsoaked value is 8.95 is increased when compared with conventionally soil and soil with quarry dust.

  12. Preparation of High Impermeable and Crack-resistance Chemical Admixture and Its Mechanism

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A kind of high impermeable and crack-resistance chemical admixture (HICRCA) was prepared, which is a compound chemical admixture composed of an expansion ingredient,density ingredient, and organic hydrophobic poreblocking ingredient. The results of the experiments indicate that the addition of HICRCA improves mortar and concrete in the following performances:(1) perfect workability: slump is more than 22cm, the slump after 3h is about 16cm; (2)high impermeability:for the mortar,the pervious height under a water pressure of 1.5MPa is 1.5cm,for the concrete, the pervious height under a water pressure of 5.0MPa is 2.2cm;(3)high crack-resistance:there is a micro-expansion at the age of 90d;(4)high compressivestrength:compared with the controlled concrete,the compressive strengths at the age of 3d and 28d are improved by 66.4% and 62.0%, respectively.At the same time,the effects of different curing condition on mortar and concrete expansive and shrinkage performance were studied.In addition,the impermeable and crack-resistance mechanism was investigated in the present paper.

  13. Growth and characterization of pure and semiorganic nonlinear optical Lithium Sulphate admixtured l-alanine crystal

    Science.gov (United States)

    Vela, T.; Selvarajan, P.; Freeda, T. H.; Balasubramanian, K.

    2013-04-01

    Lithium sulphate admixtured l-alanine (LSLA) salt was synthesized and the solubility of the commercially available l-alanine and the synthesized LSLA sample was determined in de-ionized water at various temperatures. In accordance with the solubility data, the saturated aqueous solutions of l-alanine and lithium admixtured l-alanine were prepared separately and the single crystals of the samples were grown by the solution method with a slow evaporation technique. Studying single x-ray diffraction shows that pure and LSLA crystal belong to the orthorhombic system with a non-centrosymmetric space group P212121. Using the powder x-ray diffraction study, the crystallinity of the grown crystals is confirmed and the diffraction peaks are indexed. The various functional groups present in the pure and LSLA crystal are elucidated from Fourier transform infrared spectroscopy study. UV-visible transmittance is recorded to study the optical transmittance range for the grown crystals. The powder second harmonic generation test confirms the nonlinear optical property of the grown crystals. From the microhardness test, the hardness of the grown crystals is estimated. The dielectric behaviour, such as the dielectric constant and the loss of the sample, are measured as a function of temperature and frequency. The ac conductivity of the grown crystals is also studied and the activation energy is calculated.

  14. Growth and characterization of pure and semiorganic nonlinear optical Lithium Sulphate admixtured l-alanine crystal

    International Nuclear Information System (INIS)

    Lithium sulphate admixtured l-alanine (LSLA) salt was synthesized and the solubility of the commercially available l-alanine and the synthesized LSLA sample was determined in de-ionized water at various temperatures. In accordance with the solubility data, the saturated aqueous solutions of l-alanine and lithium admixtured l-alanine were prepared separately and the single crystals of the samples were grown by the solution method with a slow evaporation technique. Studying single x-ray diffraction shows that pure and LSLA crystal belong to the orthorhombic system with a non-centrosymmetric space group P212121. Using the powder x-ray diffraction study, the crystallinity of the grown crystals is confirmed and the diffraction peaks are indexed. The various functional groups present in the pure and LSLA crystal are elucidated from Fourier transform infrared spectroscopy study. UV–visible transmittance is recorded to study the optical transmittance range for the grown crystals. The powder second harmonic generation test confirms the nonlinear optical property of the grown crystals. From the microhardness test, the hardness of the grown crystals is estimated. The dielectric behaviour, such as the dielectric constant and the loss of the sample, are measured as a function of temperature and frequency. The ac conductivity of the grown crystals is also studied and the activation energy is calculated. (paper)

  15. EFFICIENT NANO-SCALE ADMIXTURE FOR FOAM STABILITY IMPROVEMENT OF CELLULAR CONCRETES

    Directory of Open Access Journals (Sweden)

    Grishina Аnna Nikolaevna

    2012-10-01

    Full Text Available The authors present their methodology of synthesis of a nano-scale additive designated for the stabilization of synthetic foaming agents. The nano-scale admixture is composed of iron hydroxide (III sol and aqueous sodium hydro silicates (water glass. Besides the above method, the topological structural model of the nano-scale additive is proposed. The additive stability was assessed upon its one-day storage (with the foaming agent added, and the assessment data are provided in the article. The authors have discovered that it is advisable to use an iron chloride solution in the concentration of 1 % to manufacture the iron hydroxide (III sol. The authors have also discovered that the rate of jellification goes up in the process of injecting the foaming agent into the foam that contains the nano-scale admixture developed by the authors. Dependence between the amount of sodium hydro silicate and the viscosity of the system composed of the water glass and the sol of iron hydroxide (III is examined in detail. The authors have identified that the average water glass viscosity curve demonstrates an extreme nature. The additive is used for the stabilization of the foam generated by synthetic foaming agents. The injection of the proposed additive improves foam stability. It is noteworthy that this positive result is free from any negative side effects.

  16. Limit on a right-handed admixture to the weak b→c current from semileptonic decays

    International Nuclear Information System (INIS)

    We determine an upper bound for a possible right-handed b→c quark current admixture in semileptonic B→Xcl-ν decays from a simultaneous fit to moments of the lepton-energy and hadronic-mass distribution measured as a function of the lower limit on the lepton energy, using data measured by the BABAR detector. The right-handed admixture is parametrized by a new parameter cR as coefficient of computed moments with right-handed quark current. For the standard-model part we use the prediction of the heavy-quark expansion up to order 1/mb3 and perturbative corrections and for the right-handed contribution only up to order 1/mb2 and perturbative corrections. We find cR'=0.05-0.50+0.33 in agreement with the standard-model prediction of zero. Additionally, we give a constraint on a possible right-handed admixture from exclusive decays, which is with a value of cR'=0.01±0.03 more restrictive than our value from the inclusive fit. The difference in |Vcb| between the inclusive and exclusive extraction is only slightly reduced when allowing for a right-handed admixture in the range of cR'=0.01±0.03.

  17. Secondary contact and admixture between independently invading populations of the western corn rootworm, Diabrotica virgifera virgifera in Europe.

    Directory of Open Access Journals (Sweden)

    Gérald Bermond

    Full Text Available The western corn rootworm, Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae, is one of the most destructive pests of corn in North America and is currently invading Europe. The two major invasive outbreaks of rootworm in Europe have occurred, in North-West Italy and in Central and South-Eastern Europe. These two outbreaks originated from independent introductions from North America. Secondary contact probably occurred in North Italy between these two outbreaks, in 2008. We used 13 microsatellite markers to conduct a population genetics study, to demonstrate that this geographic contact resulted in a zone of admixture in the Italian region of Veneto. We show that i genetic variation is greater in the contact zone than in the parental outbreaks; ii several signs of admixture were detected in some Venetian samples, in a bayesian analysis of the population structure and in an approximate bayesian computation analysis of historical scenarios and, finally, iii allelic frequency clines were observed at microsatellite loci. The contact between the invasive outbreaks in North-West Italy and Central and South-Eastern Europe resulted in a zone of admixture, with particular characteristics. The evolutionary implications of the existence of a zone of admixture in Northern Italy and their possible impact on the invasion success of the western corn rootworm are discussed.

  18. The Effect of a Plasticizing Admixture on the Properties of Hardened Concrete

    Directory of Open Access Journals (Sweden)

    Anastasija Abasova

    2012-11-01

    Full Text Available Concrete is material obtained mixing matrix material, coarse and small aggregates and water along with additives acquiring necessary properties of hardening. The quality and properties of raw material used for manufacturing concrete, V/C ratio and the uniformity of the compaction of the mixture lead to the fundamental properties of concrete. The compressive strength of concrete is one of the most important properties of concrete. The article deals with the impact of plasticizers on the structural properties of concrete choosing an optimal content of additives. Concrete plasticizers increasing the content of additive increase the strength of samples, the density and ultrasonic pulse of velocity and decrease absorption. Test results have revealed that a plasticizing admixture under dosing or overdosing can reduce the properties of concrete.

  19. Development of admixture to produce pumping-concrete with large amount of ordinary-fineness-slag

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Y.; Sun, Z.; Zhang, G. [Tongji Univ., College of Materials Science and Enginnering, Shanghai (China); Zhou, A. W. Z.; Liu, Q.; Chen, K. [HI CON Huaxi Concrete Admixtures Co., Ltd., Sichuan (China)

    1998-12-31

    A special admixture - WZ - which can be applied to prepare pumping-concrete with large amount of OFS to solve the strength problem of slag was developed. The activating components of WZ include no Cl or SO{sub 4}{sup 2}. As a result, the addition of WZ is an effective way to make use of industrial waste, reduce the cost of concrete, improve its durability, and protect the environment at the same time. Impermeability, freezing-thawing resistance, chemical corrosion resistance and resistance to carbonation were found to be superior to concrete of the same strength using only cement as bonding material. Dry shrinking ratio was less than the shrinking ratio for ordinary concrete. 6 refs., 8 tabs., 1 fig.

  20. Ancestry inference in complex admixtures via variable-length Markov chain linkage models.

    Science.gov (United States)

    Rodriguez, Jesse M; Bercovici, Sivan; Elmore, Megan; Batzoglou, Serafim

    2013-03-01

    Inferring the ancestral origin of chromosomal segments in admixed individuals is key for genetic applications, ranging from analyzing population demographics and history, to mapping disease genes. Previous methods addressed ancestry inference by using either weak models of linkage disequilibrium, or large models that make explicit use of ancestral haplotypes. In this paper we introduce ALLOY, an efficient method that incorporates generalized, but highly expressive, linkage disequilibrium models. ALLOY applies a factorial hidden Markov model to capture the parallel process producing the maternal and paternal admixed haplotypes, and models the background linkage disequilibrium in the ancestral populations via an inhomogeneous variable-length Markov chain. We test ALLOY in a broad range of scenarios ranging from recent to ancient admixtures with up to four ancestral populations. We show that ALLOY outperforms the previous state of the art, and is robust to uncertainties in model parameters. PMID:23421795

  1. Probing background ionization: Positive streamers with varying pulse repetition rate and with a radioactive admixture

    CERN Document Server

    Nijdam, S; van Veldhuizen, E M; Ebert, U

    2011-01-01

    Positive streamers need a source of free electrons ahead of them to propagate. A streamer can supply these electrons by itself through photo-ionization, or the electrons can be present due to external background ionization. Here we investigate the effects of background ionization on streamer propagation and morphology by changing the gas composition and the repetition rate of the voltage pulses, and by adding a small amount of radioactive Krypton 85. We find that the general morphology of a positive streamer discharge in high purity nitrogen depends on background ionization: at lower background ionization levels the streamers branch more and have a more feather-like appearance. This is observed both when varying the repetition rate and when adding Krypton 85, though side branches are longer with the radioactive admixture. But velocities and minimal diameters of streamers are virtually independent of the background ionization level. In air, the inception cloud breaks up into streamers at a smaller radius when ...

  2. THE EFFECT OF 800 0C ON BOND STRENGTH OF CONCRETE WITH MINERAL ADMIXTURE

    Directory of Open Access Journals (Sweden)

    Ahmet COŞKUN

    2007-03-01

    Full Text Available The effect of high temperature (800 0C on the bond strength between concrete and rebar was investigated. In addition to concrete mixture with only portland cement, concrete mixtures with 10% silica fume and 15 % fly ash replacing cement by weight was prepared. Maximum aggregate size is as 16 mm. The 150×150×150 mm cube specimens were prepared for compressive strength and the 100×200 mm cylinder specimens were prepared for bond strength. The specimens were cured in air for 270 days after curing in water 20±2 °C for 28 days. After being heated to temperatures of 800 ºC, compressive strength and bond strength of concrete were tested. The results showed that specimens with silica fume always gave the highest values followed by those as specimens with fly ash and specimens without mineral admixtures irrespective of type and age of concrete and test methods.

  3. Influence of Shrinkage-Reducing Admixtures on the Development of Plastic Shrinkage Cracks

    DEFF Research Database (Denmark)

    Lura, Pietro; Pease, Bradley Justin; Mazzotta, Guy;

    2007-01-01

    The term plastic shrinkage cracking is generally used to describe cracks that form between the time when concrete is placed and the time when concrete sets. This paper discusses how the evaporation of water causes concave menisci to form on the surface of fresh concrete. These menisci cause both...... settlement of the concrete and tensile stress development in the surface of the concrete, which increase the potential for development of plastic shrinkage cracks. Specifically, this paper studies the development of plastic shrinkage cracks in mortars containing a commercially available shrinkage......-reducing admixture (SRA). Mortars containing SRA show fewer and narrower plastic shrinkage cracks than plain mortars when exposed to the same environmental conditions. It is proposed that the lower surface tension of the pore fluid in the mortars containing SRA results in less evaporation, reduced settlement...

  4. Plastic shrinkage of mortars with shrinkage reducing admixture and lightweight aggregates studied by neutron tomography

    Energy Technology Data Exchange (ETDEWEB)

    Wyrzykowski, Mateusz, E-mail: mateusz.wyrzykowski@empa.ch [Empa, Swiss Federal Laboratories for Materials Science and Technology, Concrete and Construction Chemistry Laboratory, Dübendorf (Switzerland); Lodz University of Technology, Department of Building Physics and Building Materials, Lodz (Poland); Trtik, Pavel [Paul Scherrer Institute, Laboratory for Neutron Scattering and Imaging, Villigen (Switzerland); Empa, Swiss Federal Laboratories for Materials Science and Technology, Concrete and Construction Chemistry Laboratory, Dübendorf (Switzerland); Münch, Beat [Empa, Swiss Federal Laboratories for Materials Science and Technology, Concrete and Construction Chemistry Laboratory, Dübendorf (Switzerland); Weiss, Jason [Purdue University, School of Civil Engineering, West Lafayette (United States); Vontobel, Peter [Paul Scherrer Institute, Laboratory for Neutron Scattering and Imaging, Villigen (Switzerland); Lura, Pietro [Empa, Swiss Federal Laboratories for Materials Science and Technology, Concrete and Construction Chemistry Laboratory, Dübendorf (Switzerland); ETH Zurich, Institute for Building Materials (IfB), Zurich (Switzerland)

    2015-07-15

    Water transport in fresh, highly permeable concrete and rapid water evaporation from the concrete surface during the first few hours after placement are the key parameters influencing plastic shrinkage cracking. In this work, neutron tomography was used to determine both the water loss from the concrete surface due to evaporation and the redistribution of fluid that occurs in fresh mortars exposed to external drying. In addition to the reference mortar with a water to cement ratio (w/c) of 0.30, a mortar with the addition of pre-wetted lightweight aggregates (LWA) and a mortar with a shrinkage reducing admixture (SRA) were tested. The addition of SRA reduced the evaporation rate from the mortar at the initial stages of drying and reduced the total water loss. The pre-wetted LWA released a large part of the absorbed water as a consequence of capillary pressure developing in the fresh mortar due to evaporation.

  5. An experimental study of the combustion characteristics of groundnut shell and waste paper admixture briquettes

    Directory of Open Access Journals (Sweden)

    O. A. Oyelaran

    2015-12-01

    Full Text Available The study was undertaken to assess the heat released of briquettes produced from waste paper and groundnut shell admixture in five mixing ratios (90:10; 80:20; 70:30; 60:40; and 50:50. The briquettes were prepared on an existing motorized briquetting machine. The suitability of briquetted fuel as domestic fuel was studied in terms of flame propagation, afterglow, calorific value, and utilized heat, after sun drying the prepared briquettes for nineteen (19 days. The results of propagation rate and afterglow obtained for all the six compositions are satisfactory they range between 0.13 to 0.14 and 365 to 380 respectively. These energy values obtained for the whole samples are sufficient enough to produce heat required for household cooking and small scale industrial cottage applications. Finally it was observed that composition variation affects the properties of the briquettes.

  6. Effect of Admixtures on the Yield Stresses of Cement Pastes under High Hydrostatic Pressures

    Directory of Open Access Journals (Sweden)

    Hong Jae Yim

    2016-03-01

    Full Text Available When cement-based materials are transported at a construction site, they undergo high pressures during the pumping process. The rheological properties of the materials under such high pressures are unknown, and estimating the workability of the materials after pumping is a complex problem. Among various influential factors on the rheology of concrete, this study investigated the effect of mineral and chemical admixtures on the high-pressure rheology. A rheometer was fabricated that could measure the rheological properties while maintaining a high pressure to simulate the pumping process. The effects of superplasticizer, silica fume, nanoclay, fly ash, or ground granulated blast furnace slag were investigated when mixed with two control cement pastes. The water-to-cement ratios were 0.35 and 0.50.

  7. Effect of Some Admixtures on the Hydration of Silica Fume and Hydrated Lime

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The effects of sodium salt of naphthalene formaldehyde sulfonic acid and stearic acid on the hydration of silica fume and Ca(0H)2 have been investigated. The hydration was carried out at 60℃ and W/S ratio of 4 for various time intervals namely, 1, 3, 7 and 28 days and in the presence of 0.2% and 5% superplasticizer and stearic acid. The results of the hydration kinetics show that both admixtures accelerate the hydration reaction of silica fume and calcium hydroxide during the first 7 days. Whereas, after 28 days hydration there is no significant effect. Generally, most of free calcium hydroxide seems to be consumed after 28 days. In addition, the phase composition as well as the microstructure of the formed hydrates was examined by using X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM) respectively.

  8. Some radiation-optical properties of fluorphlogopite with admixture of vanadium

    Energy Technology Data Exchange (ETDEWEB)

    Avesov, A.D.; Gasanov, E.M. (AN Uzbekskoj SSR, Tashkent. Inst. Yadernoj Fiziki)

    1982-10-16

    A study is reported on crystals of synthetic mica fluorphlogopite KMg/sub 3/(AlSi/sub 3/O/sub 10/)F/sub 2/ with vanadium admixtures of 0.5 to 5%. Optical absorption spectra of fluorphlogopite samples neutron irradiated with doses of 10/sup 18/, 5 x 10/sup 18/, and 2.5 x 10/sup 19/ cm/sup -2/ show additional absorption bands at 300 to 330 and 560 nm. Most clearly these bands are observed in samples having small amounts of V/sub 2/O/sub 5/. It was concluded that under neutron irradiation in vanadium fluorphlogopite substitution of F/sup -/ anions by O/sup 2 -/ anions takes place, coupled with a valence transition V/sup 2 +/ ..-->.. V/sup 3 +/ upon growing irradiation dose.

  9. Plastic shrinkage of mortars with shrinkage reducing admixture and lightweight aggregates studied by neutron tomography

    International Nuclear Information System (INIS)

    Water transport in fresh, highly permeable concrete and rapid water evaporation from the concrete surface during the first few hours after placement are the key parameters influencing plastic shrinkage cracking. In this work, neutron tomography was used to determine both the water loss from the concrete surface due to evaporation and the redistribution of fluid that occurs in fresh mortars exposed to external drying. In addition to the reference mortar with a water to cement ratio (w/c) of 0.30, a mortar with the addition of pre-wetted lightweight aggregates (LWA) and a mortar with a shrinkage reducing admixture (SRA) were tested. The addition of SRA reduced the evaporation rate from the mortar at the initial stages of drying and reduced the total water loss. The pre-wetted LWA released a large part of the absorbed water as a consequence of capillary pressure developing in the fresh mortar due to evaporation

  10. Influence of Mineral Admixtures on the Permeability of Lightweight Aggregate Concrete

    Institute of Scientific and Technical Information of China (English)

    WANG Fazhou; HU Shuguang; DING Qingjun; PENG yanzhou

    2005-01-01

    The permeability of lightweight aggregate concrete was studied. Some efforts were taken to increase the resistance of lightweight aggregate concrete (LC) to water penetration by using the mineral admixtures of fly ash, granulated blast furnace slag or silica fume. Accelerated chloride penetrability test and liquid atmosphere press method were used to study the anti-permeability of lightweight aggregate concrete. The experimental results show that fly ash, granulated blast furnace slag and silica fume can decrease the permeability of lightweight aggregate concrete, but the effect of granulated blast furnace slag is poor. According to the SEM and pore structure analyzing results,an interface self-reinforcing effect model was presented and the reinforced mechanism of mineral mixture on LC was discussed according to the model described by authors.

  11. Global genetic variation at OAS1 provides evidence of archaic admixture in Melanesian populations.

    Science.gov (United States)

    Mendez, Fernando L; Watkins, Joseph C; Hammer, Michael F

    2012-06-01

    Recent analysis of DNA extracted from two Eurasian forms of archaic human shows that more genetic variants are shared with humans currently living in Eurasia than with anatomically modern humans in sub-Saharan Africa. Although these genome-wide average measures of genetic similarity are consistent with the hypothesis of archaic admixture in Eurasia, analyses of individual loci exhibiting the signal of archaic introgression are needed to test alternative hypotheses and investigate the admixture process. Here, we provide a detailed sequence analysis of the innate immune gene OAS1, a locus with a divergent Melanesian haplotype that is very similar to the Denisova sequence from the Altai region of Siberia. We resequenced a 7-kb region encompassing the OAS1 gene in 88 individuals from six Old World populations (San, Biaka, Mandenka, French Basque, Han Chinese, and Papua New Guineans) and discovered previously unknown and ancient genetic variation. The 5' region of this gene has unusual patterns of diversity, including 1) higher levels of nucleotide diversity in Papuans than in sub-Saharan Africans, 2) very deep ancestry with an estimated time to the most recent common ancestor of >3 myr, and 3) a basal branching pattern with Papuan individuals on either side of the rooted network. A global geographic survey of >1,500 individuals showed that the divergent Papuan haplotype is nearly restricted to populations from eastern Indonesia and Melanesia. Polymorphic sites within this haplotype are shared with the draft Denisova genome over a span of ∼90 kb and are associated with an extended block of linkage disequilibrium, supporting the hypothesis that this haplotype introgressed from an archaic source that likely lived in Eurasia. PMID:22319157

  12. Genetic structure of the population of Cabo Verde (west Africa): evidence of substantial European admixture.

    Science.gov (United States)

    Parra, E J; Ribeiro, J C; Caeiro, J L; Riveiro, A

    1995-08-01

    The population of Cabo Verde was founded in the fifteenth century (1462), on the basis of slaves brought from the West African coast and a few Europeans, mainly from Portugal. The polymorphism of six red cell enzymes (ADA, AK1, ALAD, ESD, GLO1, and PGD) and ten plasma proteins (AHSG, BF, F13A, F13B, GC, HP, ORM, PLG, TBG, and TF) was studied in a sample of 268 individuals from Cabo Verde (West Africa). There is no statistical evidence of genetic heterogeneity between the two groups of islands which constitute the archipelago, Barlavento and Sotavento. The gene frequency distribution observed in Cabo Verde differs, in many markers, from that of West African populations, suggesting an important European influence. The proportion of Caucasian genes in the population of Cabo Verde has been calculated to be M = 0.3634 +/- 0.0510, and the considerable dispersion of the locus-specific admixture estimates seems to indicate random drift has also played a role in the evolution of the allele frequencies in the archipelago. Partition of the variance of the mean estimate in evolutionary and sampling variance shows the evolutionary variance is more than ten times higher than the sampling variance. When dendrograms are constructed on the basis of different genetic distances, the population of Cabo Verde clusters with Afro-Americans, forming a different group from the populations of the African continent. This is interpreted as a consequence of the importance of Caucasian admixture both in Afro-Americans and in the population of Cabo Verde. PMID:7485435

  13. No clear effect of admixture between two European invading outbreaks of Diabrotica virgifera virgifera in natura.

    Directory of Open Access Journals (Sweden)

    Gérald Bermond

    Full Text Available In this study, we challenged the hypothesis that admixture may have had a positive impact in the context of the European invasion of the western corn rootworm (WCR, Diabrotica virgifera virgifera, LeConte. This beetle was introduced in Europe from the USA several times since the 1980's. The multiple introductions of this major pest of cultivated corn led to the formation of two major outbreaks in North Western (NW Italy and in Central and South Eastern (CSE Europe that eventually merged into a secondary contact zone where insects from both outbreaks interbreed. We collected about 600 insects from this contact zone and genotyped them using 13 microsatellite markers. Three types of information were obtained from the collected individuals: (i their survival under starvation; (ii their admixed status, determined through a Bayesian method of genetic clustering and (iii their mating probability, studied via the detection, isolation and genotyping of sperm in female spermathecae. Twenty six % and 12% of the individuals were assigned to the NW Italy or the CSE Europe parental types, respectively, and 23% and 39% to the F1 and backcross hybrid types, respectively. Globally, our results do not reveal any significant impact of the admixed status on the mating probability and on the choice of mating partners. However the admixed status had a sex- and sampling site-dependent effect on survival in adults under starvation. In addition sex had an effect on survival, with mortality hazard about 3 times larger in males than in females. The consequences of these findings for the evolution of the admixture zone of northern Italy are discussed.

  14. Origin and dynamics of admixture in Brazilians and its effect on the pattern of deleterious mutations.

    Science.gov (United States)

    Kehdy, Fernanda S G; Gouveia, Mateus H; Machado, Moara; Magalhães, Wagner C S; Horimoto, Andrea R; Horta, Bernardo L; Moreira, Rennan G; Leal, Thiago P; Scliar, Marilia O; Soares-Souza, Giordano B; Rodrigues-Soares, Fernanda; Araújo, Gilderlanio S; Zamudio, Roxana; Sant Anna, Hanaisa P; Santos, Hadassa C; Duarte, Nubia E; Fiaccone, Rosemeire L; Figueiredo, Camila A; Silva, Thiago M; Costa, Gustavo N O; Beleza, Sandra; Berg, Douglas E; Cabrera, Lilia; Debortoli, Guilherme; Duarte, Denise; Ghirotto, Silvia; Gilman, Robert H; Gonçalves, Vanessa F; Marrero, Andrea R; Muniz, Yara C; Weissensteiner, Hansi; Yeager, Meredith; Rodrigues, Laura C; Barreto, Mauricio L; Lima-Costa, M Fernanda; Pereira, Alexandre C; Rodrigues, Maíra R; Tarazona-Santos, Eduardo

    2015-07-14

    While South Americans are underrepresented in human genomic diversity studies, Brazil has been a classical model for population genetics studies on admixture. We present the results of the EPIGEN Brazil Initiative, the most comprehensive up-to-date genomic analysis of any Latin-American population. A population-based genome-wide analysis of 6,487 individuals was performed in the context of worldwide genomic diversity to elucidate how ancestry, kinship, and inbreeding interact in three populations with different histories from the Northeast (African ancestry: 50%), Southeast, and South (both with European ancestry >70%) of Brazil. We showed that ancestry-positive assortative mating permeated Brazilian history. We traced European ancestry in the Southeast/South to a wider European/Middle Eastern region with respect to the Northeast, where ancestry seems restricted to Iberia. By developing an approximate Bayesian computation framework, we infer more recent European immigration to the Southeast/South than to the Northeast. Also, the observed low Native-American ancestry (6-8%) was mostly introduced in different regions of Brazil soon after the European Conquest. We broadened our understanding of the African diaspora, the major destination of which was Brazil, by revealing that Brazilians display two within-Africa ancestry components: one associated with non-Bantu/western Africans (more evident in the Northeast and African Americans) and one associated with Bantu/eastern Africans (more present in the Southeast/South). Furthermore, the whole-genome analysis of 30 individuals (42-fold deep coverage) shows that continental admixture rather than local post-Columbian history is the main and complex determinant of the individual amount of deleterious genotypes. PMID:26124090

  15. Genetic origin, admixture, and asymmetry in maternal and paternal human lineages in Cuba

    Directory of Open Access Journals (Sweden)

    Martínez-Fuentes Antonio

    2008-07-01

    Full Text Available Abstract Background Before the arrival of Europeans to Cuba, the island was inhabited by two Native American groups, the Tainos and the Ciboneys. Most of the present archaeological, linguistic and ancient DNA evidence indicates a South American origin for these populations. In colonial times, Cuban Native American people were replaced by European settlers and slaves from Africa. It is still unknown however, to what extent their genetic pool intermingled with and was 'diluted' by the arrival of newcomers. In order to investigate the demographic processes that gave rise to the current Cuban population, we analyzed the hypervariable region I (HVS-I and five single nucleotide polymorphisms (SNPs in the mitochondrial DNA (mtDNA coding region in 245 individuals, and 40 Y-chromosome SNPs in 132 male individuals. Results The Native American contribution to present-day Cubans accounted for 33% of the maternal lineages, whereas Africa and Eurasia contributed 45% and 22% of the lineages, respectively. This Native American substrate in Cuba cannot be traced back to a single origin within the American continent, as previously suggested by ancient DNA analyses. Strikingly, no Native American lineages were found for the Y-chromosome, for which the Eurasian and African contributions were around 80% and 20%, respectively. Conclusion While the ancestral Native American substrate is still appreciable in the maternal lineages, the extensive process of population admixture in Cuba has left no trace of the paternal Native American lineages, mirroring the strong sexual bias in the admixture processes taking place during colonial times.

  16. Multilocus Bayesian Estimates of Intra-Oceanic Genetic Differentiation, Connectivity, and Admixture in Atlantic Swordfish (Xiphias gladius L..

    Directory of Open Access Journals (Sweden)

    Brad L Smith

    Full Text Available Previous genetic studies of Atlantic swordfish (Xiphias gladius L. revealed significant differentiation among Mediterranean, North Atlantic and South Atlantic populations using both mitochondrial and nuclear DNA data. However, limitations in geographic sampling coverage, and the use of single loci, precluded an accurate placement of boundaries and of estimates of admixture. In this study, we present multilocus analyses of 26 single nucleotide polymorphisms (SNPs within 10 nuclear genes to estimate population differentiation and admixture based on the characterization of 774 individuals representing North Atlantic, South Atlantic, and Mediterranean swordfish populations. Pairwise FST values, AMOVA, PCoA, and Bayesian individual assignments support the differentiation of swordfish inhabiting these three basins, but not the current placement of the boundaries that separate them. Specifically, the range of the South Atlantic population extends beyond 5°N management boundary to 20°N-25°N from 45°W. Likewise the Mediterranean population extends beyond the current management boundary at the Strait of Gibraltar to approximately 10°W. Further, admixture zones, characterized by asymmetric contributions of adjacent populations within samples, are confined to the Northeast Atlantic. While South Atlantic and Mediterranean migrants were identified within these Northeast Atlantic admixture zones no North Atlantic migrants were identified respectively in these two neighboring basins. Owing to both, the characterization of larger number of loci and a more ample spatial sampling coverage, it was possible to provide a finer resolution of the boundaries separating Atlantic swordfish populations than previous studies. Finally, the patterns of population structure and admixture are discussed in the light of the reproductive biology, the known patterns of dispersal, and oceanographic features that may act as barriers to gene flow to Atlantic swordfish.

  17. A Generic Procedure for the Assessment of the Effect of Concrete Admixtures on the Sorption of Radionuclides on Cement: Concept and Selected Results

    Energy Technology Data Exchange (ETDEWEB)

    Glaus, M.A.; Laube, A.; Van Loon, L.R

    2004-03-01

    A screening procedure is proposed for the assessment of the effect of concrete admixtures on the sorption of radionuclides by cement. The procedure is both broad and generic, and can thus be used as input for the assessment of concrete admixtures which might be used in the future. The experimental feasibility and significance of the screening procedure are tested using selected concrete admixtures: i.e. sulfonated naphthalene-formaldehyde condensates, lignosulfonates, and a plasticiser used at PSI for waste conditioning. The effect of these on the sorption properties of Ni(II), Eu(III) and Th(IV) in cement is investigated using crushed Hardened Cement Paste (HCP), as well as cement pastes prepared in the presence of these admixtures. Strongly adverse effects on the sorption of the radionuclides tested are observed only in single cases, and under extreme conditions: i.e. at high ratios of concrete admixtures to HCP, and at low ratios of HCP to cement pore water. Under realistic conditions, both radionuclide sorption and the sorption of isosaccharinic acid (a strong complexant produced in cement-conditioned wastes containing cellulose) remain unaffected by the presence of concrete admixtures, which can be explained by the sorption of them onto the HCP. The pore-water concentrations of the concrete admixtures tested are thereby reduced to levels at which the formation of radionuclide complexes is no longer of importance. Further, the Langmuir sorption model, proposed for the sorption of concrete admixtures on HCP, suggests that the HCP surface does not become saturated, at least for those concrete admixtures tested. (author)

  18. A Generic Procedure for the Assessment of the Effect of Concrete Admixtures on the Sorption of Radionuclides on Cement: Concept and Selected Results

    International Nuclear Information System (INIS)

    A screening procedure is proposed for the assessment of the effect of concrete admixtures on the sorption of radionuclides by cement. The procedure is both broad and generic, and can thus be used as input for the assessment of concrete admixtures which might be used in the future. The experimental feasibility and significance of the screening procedure are tested using selected concrete admixtures: i.e. sulfonated naphthalene-formaldehyde condensates, lignosulfonates, and a plasticiser used at PSI for waste conditioning. The effect of these on the sorption properties of Ni(II), Eu(III) and Th(IV) in cement is investigated using crushed Hardened Cement Paste (HCP), as well as cement pastes prepared in the presence of these admixtures. Strongly adverse effects on the sorption of the radionuclides tested are observed only in single cases, and under extreme conditions: i.e. at high ratios of concrete admixtures to HCP, and at low ratios of HCP to cement pore water. Under realistic conditions, both radionuclide sorption and the sorption of isosaccharinic acid (a strong complexant produced in cement-conditioned wastes containing cellulose) remain unaffected by the presence of concrete admixtures, which can be explained by the sorption of them onto the HCP. The pore-water concentrations of the concrete admixtures tested are thereby reduced to levels at which the formation of radionuclide complexes is no longer of importance. Further, the Langmuir sorption model, proposed for the sorption of concrete admixtures on HCP, suggests that the HCP surface does not become saturated, at least for those concrete admixtures tested. (author)

  19. Ad Hoc versus Standardized Admixtures for Continuous Infusion Drugs in Neonatal Intensive Care: Cognitive Task Analysis of Safety at the Bedside

    OpenAIRE

    Brannon, Timothy S.

    2006-01-01

    Continuous infusion intravenous (IV) drugs in neonatal intensive care are usually prepared based on patient weight so that the dose is readable as a simple multiple of the infusion pump rate. New safety guidelines propose that hospitals switch to using standardized admixtures of these drugs to prevent calculation errors during ad hoc preparation. Extended hierarchical task analysis suggests that switching to standardized admixtures may lead to more errors in programming the pump at the bedside.

  20. Influence of the calcium concentration in the presence of organic phosphorus on the physicochemical compatibility and stability of all-in-one admixtures for neonatal use

    Directory of Open Access Journals (Sweden)

    de Sousa Valeria

    2009-10-01

    Full Text Available Abstract Background Preterm infants need high amounts of calcium and phosphorus for bone mineralization, which is difficult to obtain with parenteral feeding due to the low solubility of these salts. The objective of this study was to evaluate the physicochemical compatibility of high concentrations of calcium associated with organic phosphate and its influence on the stability of AIO admixtures for neonatal use. Methods Three TPN admixture formulas were prepared in multilayered bags. The calcium content of the admixtures was adjusted to 0, 46.5 or 93 mg/100 ml in the presence of a fixed organic phosphate concentration as well as lipids, amino acids, inorganic salts, glucose, vitamins and oligoelements at pH 5.5. Each admixture was stored at 4°C, 25°C or 37°C and evaluated over a period of 7 days. The physicochemical stability parameters evaluated were visual aspect, pH, sterility, osmolality, peroxide formation, precipitation, and the size of lipid globules. Results Color alterations occurred from the first day on, and reversible lipid film formation from the third day of study for the admixtures stored at 25°C and 37°C. According to the parameters evaluated, the admixtures were stable at 4°C; and none of them presented precipitated particles due to calcium/phosphate incompatibility or lipid globules larger than 5 μm, which is the main parameter currently used to evaluate lipid emulsion stability. The admixtures maintained low peroxide levels and osmolarity was appropriate for parenteral administration. Conclusion The total calcium and calcium/phosphorus ratios studied appeared not to influence the physicochemical compatibility and stability of AIO admixtures.

  1. The ion-selective field-effect transistor application for enzyme analysis of toxic admixtures in aqueous solutions

    Directory of Open Access Journals (Sweden)

    Pavluchenko A. S.

    2010-06-01

    Full Text Available The article describes design and production technology of pH-sensors based on ion-selective field-effect transis-tors (ISFET intended for enzyme analysis of inhibiting admixtures in aqueous solutions, and architecture of the multichannel measuring system built upon the ISFET-sensors. The characteristics of developed prototypes are given and the ways for further improvement of system design, metrological performance and operating parameters are outlined.

  2. Cuba: exploring the history of admixture and the genetic basis of pigmentation using autosomal and uniparental markers.

    Directory of Open Access Journals (Sweden)

    Beatriz Marcheco-Teruel

    2014-07-01

    Full Text Available We carried out an admixture analysis of a sample comprising 1,019 individuals from all the provinces of Cuba. We used a panel of 128 autosomal Ancestry Informative Markers (AIMs to estimate the admixture proportions. We also characterized a number of haplogroup diagnostic markers in the mtDNA and Y-chromosome in order to evaluate admixture using uniparental markers. Finally, we analyzed the association of 16 single nucleotide polymorphisms (SNPs with quantitative estimates of skin pigmentation. In the total sample, the average European, African and Native American contributions as estimated from autosomal AIMs were 72%, 20% and 8%, respectively. The Eastern provinces of Cuba showed relatively higher African and Native American contributions than the Western provinces. In particular, the highest proportion of African ancestry was observed in the provinces of Guantánamo (40% and Santiago de Cuba (39%, and the highest proportion of Native American ancestry in Granma (15%, Holguín (12% and Las Tunas (12%. We found evidence of substantial population stratification in the current Cuban population, emphasizing the need to control for the effects of population stratification in association studies including individuals from Cuba. The results of the analyses of uniparental markers were concordant with those observed in the autosomes. These geographic patterns in admixture proportions are fully consistent with historical and archaeological information. Additionally, we identified a sex-biased pattern in the process of gene flow, with a substantially higher European contribution from the paternal side, and higher Native American and African contributions from the maternal side. This sex-biased contribution was particularly evident for Native American ancestry. Finally, we observed that SNPs located in the genes SLC24A5 and SLC45A2 are strongly associated with melanin levels in the sample.

  3. Effect of Expansive Admixtures on the Shrinkage and Mechanical Properties of High-Performance Fiber-Reinforced Cement Composites

    OpenAIRE

    Won-Chang Choi; Hyun-Do Yun

    2013-01-01

    High-performance fiber-reinforced cement composites (HPFRCCs) are characterized by strain-hardening and multiple cracking during the inelastic deformation process, but they also develop high shrinkage strain. This study investigates the effects of replacing Portland cement with calcium sulfoaluminate-based expansive admixtures (CSA EXAs) to compensate for the shrinkage and associated mechanical behavior of HPFRCCs. Two types of CSA EXA (CSA-K and CSA-J), each with a different chemical composi...

  4. On the use of crystalline admixtures in cement based construction materials: from porosity reducers to promoters of self healing

    Science.gov (United States)

    Ferrara, Liberato; Krelani, Visar; Moretti, Fabio

    2016-08-01

    The project detailed in this paper aims at a thorough characterization of the effects of crystalline admixtures, currently employed as porosity reducing admixtures, on the self-healing capacity of the cementitious composites, i.e. their capacity to completely or partially re-seal cracks and, in case, also exhibit recovery of mechanical properties. The problem has been investigated with reference to both a normal strength concrete (NSC) and a high performance fibre reinforced cementitious composite (HPFRCC). In the latter case, the influence of flow-induced fibre alignment has also been considered in the experimental investigation. With reference to either 3-point (for NSC) or 4-point (for HPFRCC) bending tests performed up to controlled crack opening and up to failure, respectively before and after exposure/conditioning recovery of stiffness and stress bearing capacity has been evaluated to assess the self-healing capacity. In a durability-based design framework, self-healing indices to quantify the recovery of mechanical properties will also be defined. In NSC, crystalline admixtures are able to promote up to 60% of crack sealing even under exposure to open air. In the case of HPFRCCs, which would already feature autogenous healing capacity because of their peculiar mix compositions, the synergy between the dispersed fibre reinforcement and the action of the crystalline admixture has resulted in a likely ‘chemical pre-stressing’ of the same reinforcement, from which the recovery of mechanical performance of the material has greatly benefited, up to levels even higher than the performance of the virgin un-cracked material.

  5. Genetic dating indicates that the Asian–Papuan admixture through Eastern Indonesia corresponds to the Austronesian expansion

    OpenAIRE

    Xu, Shuhua; Pugach, Irina; Stoneking, Mark; Kayser, Manfred; Jin, Li

    2012-01-01

    Although the Austronesian expansion had a major impact on the languages of Island Southeast Asia, controversy still exists over the genetic impact of this expansion. The coexistence of both Asian and Papuan genetic ancestry in Eastern Indonesia provides a unique opportunity to address this issue. Here, we estimate recombination breakpoints in admixed genomes based on genome-wide SNP data and date the genetic admixture between populations of Asian vs. Papuan ancestry in Eastern Indonesia. Anal...

  6. Nuclear Species-Diagnostic SNP Markers Mined from 454 Amplicon Sequencing Reveal Admixture Genomic Structure of Modern Citrus Varieties

    Science.gov (United States)

    Curk, Franck; Ancillo, Gema; Ollitrault, Frédérique; Perrier, Xavier; Jacquemoud-Collet, Jean-Pierre; Garcia-Lor, Andres; Navarro, Luis; Ollitrault, Patrick

    2015-01-01

    Most cultivated Citrus species originated from interspecific hybridisation between four ancestral taxa (C. reticulata, C. maxima, C. medica, and C. micrantha) with limited further interspecific recombination due to vegetative propagation. This evolution resulted in admixture genomes with frequent interspecific heterozygosity. Moreover, a major part of the phenotypic diversity of edible citrus results from the initial differentiation between these taxa. Deciphering the phylogenomic structure of citrus germplasm is therefore essential for an efficient utilization of citrus biodiversity in breeding schemes. The objective of this work was to develop a set of species-diagnostic single nucleotide polymorphism (SNP) markers for the four Citrus ancestral taxa covering the nine chromosomes, and to use these markers to infer the phylogenomic structure of secondary species and modern cultivars. Species-diagnostic SNPs were mined from 454 amplicon sequencing of 57 gene fragments from 26 genotypes of the four basic taxa. Of the 1,053 SNPs mined from 28,507 kb sequence, 273 were found to be highly diagnostic for a single basic taxon. Species-diagnostic SNP markers (105) were used to analyse the admixture structure of varieties and rootstocks. This revealed C. maxima introgressions in most of the old and in all recent selections of mandarins, and suggested that C. reticulata × C. maxima reticulation and introgression processes were important in edible mandarin domestication. The large range of phylogenomic constitutions between C. reticulata and C. maxima revealed in mandarins, tangelos, tangors, sweet oranges, sour oranges, grapefruits, and orangelos is favourable for genetic association studies based on phylogenomic structures of the germplasm. Inferred admixture structures were in agreement with previous hypotheses regarding the origin of several secondary species and also revealed the probable origin of several acid citrus varieties. The developed species-diagnostic SNP

  7. Cuba: exploring the history of admixture and the genetic basis of pigmentation using autosomal and uniparental markers.

    Science.gov (United States)

    Marcheco-Teruel, Beatriz; Parra, Esteban J; Fuentes-Smith, Evelyn; Salas, Antonio; Buttenschøn, Henriette N; Demontis, Ditte; Torres-Español, María; Marín-Padrón, Lilia C; Gómez-Cabezas, Enrique J; Alvarez-Iglesias, Vanesa; Mosquera-Miguel, Ana; Martínez-Fuentes, Antonio; Carracedo, Angel; Børglum, Anders D; Mors, Ole

    2014-07-01

    We carried out an admixture analysis of a sample comprising 1,019 individuals from all the provinces of Cuba. We used a panel of 128 autosomal Ancestry Informative Markers (AIMs) to estimate the admixture proportions. We also characterized a number of haplogroup diagnostic markers in the mtDNA and Y-chromosome in order to evaluate admixture using uniparental markers. Finally, we analyzed the association of 16 single nucleotide polymorphisms (SNPs) with quantitative estimates of skin pigmentation. In the total sample, the average European, African and Native American contributions as estimated from autosomal AIMs were 72%, 20% and 8%, respectively. The Eastern provinces of Cuba showed relatively higher African and Native American contributions than the Western provinces. In particular, the highest proportion of African ancestry was observed in the provinces of Guantánamo (40%) and Santiago de Cuba (39%), and the highest proportion of Native American ancestry in Granma (15%), Holguín (12%) and Las Tunas (12%). We found evidence of substantial population stratification in the current Cuban population, emphasizing the need to control for the effects of population stratification in association studies including individuals from Cuba. The results of the analyses of uniparental markers were concordant with those observed in the autosomes. These geographic patterns in admixture proportions are fully consistent with historical and archaeological information. Additionally, we identified a sex-biased pattern in the process of gene flow, with a substantially higher European contribution from the paternal side, and higher Native American and African contributions from the maternal side. This sex-biased contribution was particularly evident for Native American ancestry. Finally, we observed that SNPs located in the genes SLC24A5 and SLC45A2 are strongly associated with melanin levels in the sample. PMID:25058410

  8. Admixture mapping of ankle-arm index: identification of a candidate locus associated with peripheral arterial disease

    OpenAIRE

    Scherer, Matthew L.; Nalls, Michael A; Pawlikowska, Ludmila; Ziv, Elad; Mitchell, Gary; Huntsman, Scott; Hu, Donglei; Sutton-Tyrrell, Kim; Lakatta, Edward G.; Hsueh, Wen-Chi; Newman, Anne B; Tandon, Arti; Kim, Lauren; Kwok, Pui-Yan; Sung, Andrew

    2009-01-01

    Peripheral arterial disease (PAD) is associated with significant morbidity and mortality, and has a higher prevalence in African Americans than Caucasians. Ankle arm index (AAI) is the ratio of systolic blood pressure in the leg to that in the arm, and, when low, is a marker of PAD. We used an admixture mapping approach to search for genetic loci associated with low AAI. Using data from 1040 African-American participants in the observational, population-based Health, Aging, and Body Compositi...

  9. Nuclear species-diagnostic SNP markers mined from 454 amplicon sequencing reveal admixture genomic structure of modern citrus varieties.

    Science.gov (United States)

    Curk, Franck; Ancillo, Gema; Ollitrault, Frédérique; Perrier, Xavier; Jacquemoud-Collet, Jean-Pierre; Garcia-Lor, Andres; Navarro, Luis; Ollitrault, Patrick

    2015-01-01

    Most cultivated Citrus species originated from interspecific hybridisation between four ancestral taxa (C. reticulata, C. maxima, C. medica, and C. micrantha) with limited further interspecific recombination due to vegetative propagation. This evolution resulted in admixture genomes with frequent interspecific heterozygosity. Moreover, a major part of the phenotypic diversity of edible citrus results from the initial differentiation between these taxa. Deciphering the phylogenomic structure of citrus germplasm is therefore essential for an efficient utilization of citrus biodiversity in breeding schemes. The objective of this work was to develop a set of species-diagnostic single nucleotide polymorphism (SNP) markers for the four Citrus ancestral taxa covering the nine chromosomes, and to use these markers to infer the phylogenomic structure of secondary species and modern cultivars. Species-diagnostic SNPs were mined from 454 amplicon sequencing of 57 gene fragments from 26 genotypes of the four basic taxa. Of the 1,053 SNPs mined from 28,507 kb sequence, 273 were found to be highly diagnostic for a single basic taxon. Species-diagnostic SNP markers (105) were used to analyse the admixture structure of varieties and rootstocks. This revealed C. maxima introgressions in most of the old and in all recent selections of mandarins, and suggested that C. reticulata × C. maxima reticulation and introgression processes were important in edible mandarin domestication. The large range of phylogenomic constitutions between C. reticulata and C. maxima revealed in mandarins, tangelos, tangors, sweet oranges, sour oranges, grapefruits, and orangelos is favourable for genetic association studies based on phylogenomic structures of the germplasm. Inferred admixture structures were in agreement with previous hypotheses regarding the origin of several secondary species and also revealed the probable origin of several acid citrus varieties. The developed species-diagnostic SNP

  10. Effect of additives with common cation on the radiolysis of ammonium, sodium and potassium nitrates in admixtures

    International Nuclear Information System (INIS)

    Gamma radiolysis of admixtures of NH4NO3, NaNO3 and KNO3 with additive salts having common cation has been studied over a wide range of nitrate salt concentration and absorbed dose. Radiolytic decomposition of nitrate salt depends on the concentration of nitrate in the admixture as well as the total absorbed dose. G(NO2-) values calculated on the basis of electron fraction of the nitrate salt decrease with the increase in mol% of the nitrate salt in somewhat exponential manner. In (NaNO3 + Na2SO4) and (KNO3 + KX, where X = Cl, Br, I) systems decomposition was found to increase linearly with the absorbed dose in the composition range of 20-100 mol%. The additives seem to exhibit sensitization effect causing extra decomposition by the energy transfer process in solid state. The efficiency of energy transfer depends on the nature of added salt, concentration of the nitrate in admixture and absorbed dose. (author)

  11. Admixture analysis of stocked brown trout populations using mapped microsatellite DNA markers: indigenous trout persist in introgressed populations.

    Science.gov (United States)

    Hansen, Michael M; Mensberg, Karen-Lise D

    2009-10-23

    Admixture between wild and captive populations is an increasing concern in conservation biology. Understanding the extent of admixture and the processes involved requires identification of admixed and non-admixed individuals. This can be achieved by statistical methods employing Bayesian clustering, but resolution is low if genetic differentiation is weak. Here, we analyse stocked brown trout populations represented by historical (1943-1956) and contemporary (2000s) samples, where genetic differentiation between wild populations and stocked trout is weak (pairwise F(ST) of 0.047 and 0.053). By analysing a high number of microsatellite DNA markers (50) and making use of linkage map information, we achieve clear identification of admixed and non-admixed trout. Moreover, despite strong population-level admixture by hatchery strain trout in one of the populations (70.8%), non-admixed individuals nevertheless persist (7 out of 53 individuals). These remnants of the indigenous population are characterized by later spawning time than the majority of the admixed individuals. We hypothesize that isolation by time mediated by spawning time differences between wild and hatchery strain trout is a major factor rescuing a part of the indigenous population from introgression. PMID:19515653

  12. In vivo efficacy and toxicity evaluation of polycaprolactone nanoparticles and aluminum based admixture formulation as vaccine delivery system.

    Science.gov (United States)

    Bansal, Vivek; Kumar, Manoj; Bhardwaj, Arun; Brahmne, H G; Singh, Harpal

    2015-10-13

    Delivery of antigen through admixture formulation containing poly caprolactone (PCL) and aluminum phosphate was studied as a promising strategy to generate antigen specific immune response. The present study demonstrates the synergistic effect of admixture formulation of PCL with reduced aluminum (PCL-Al 0.2 mg-TT and PCL-PEG-Al 0.2 mg-TT) as a potential adjuvant system using tetanus toxoid (TT) as a model antigen. On evaluation of the magnitude of efficacy for the proposed formulation by ELISA as well as challenge method, persistent and strong antibody response was obtained throughout the 180 day study period on storage at 5 ± 3 °C. In comparison to the aluminum phosphate based conventional tetanus vaccine, higher levels of IFN-γ and IL-4 were obtained with PCL-Al 0.2 mg-TT and PCL-PEG-Al 0.2 mg-TT, indicating the presence of cell mediated as well as humoral immune responses. Histopathology and serum biochemistry profile in mice further indicated the suitability of the proposed formulation. Percent adsorption/encapsulation of the antigen also increased to nearly 95% in the admixture formulation compared to 55% adsorption in the conventional tetanus vaccine. The present study established a useful baseline for designing biocompatible and effective delivery system for toxoid vaccines through judicious use of PCL based biodegradable nanoparticles in combination with aluminum phosphate. PMID:26343498

  13. Testing models of speciation from genome sequences: divergence and asymmetric admixture in Island South-East Asian Sus species during the Plio-Pleistocene climatic fluctuations.

    Science.gov (United States)

    Frantz, Laurent A F; Madsen, Ole; Megens, Hendrik-Jan; Groenen, Martien A M; Lohse, Konrad

    2014-11-01

    In many temperate regions, ice ages promoted range contractions into refugia resulting in divergence (and potentially speciation), while warmer periods led to range expansions and hybridization. However, the impact these climatic oscillations had in many parts of the tropics remains elusive. Here, we investigate this issue using genome sequences of three pig (Sus) species, two of which are found on islands of the Sunda-shelf shallow seas in Island South-East Asia (ISEA). A previous study revealed signatures of interspecific admixture between these Sus species (Genome biology, 14, 2013, R107). However, the timing, directionality and extent of this admixture remain unknown. Here, we use a likelihood-based model comparison to more finely resolve this admixture history and test whether it was mediated by humans or occurred naturally. Our analyses suggest that interspecific admixture between Sunda-shelf species was most likely asymmetric and occurred long before the arrival of humans in the region. More precisely, we show that these species diverged during the late Pliocene but around 23% of their genomes have been affected by admixture during the later Pleistocene climatic transition. In addition, we show that our method provides a significant improvement over D-statistics which are uninformative about the direction of admixture. PMID:25294645

  14. Utilization of water-reducing admixtures in cemented paste backfill of sulphide-rich mill tailings.

    Science.gov (United States)

    Ercikdi, Bayram; Cihangir, Ferdi; Kesimal, Ayhan; Deveci, Haci; Alp, Ibrahim

    2010-07-15

    This study presents the effect of three different water-reducing admixtures (WRAs) on the rheological and mechanical properties of cemented paste backfill (CPB) samples. A 28-day strength of > or = 0.7 MPa and the maintenance of the stability (i.e. > or = 0.7 MPa) over 360 days of curing were desired as the design criteria. Ordinary Portland cement (OPC) and Portland composite cement (PCC) were used as binders at 5 wt.% dose. WRAs were initially tested to determine the dosage of a WRA for a required consistency of 7'' for CPB mixtures. A total of 192 CPB samples were then prepared using WRAs. The utilization of WRAs enhanced the flow characteristics of the CPB mixture and allowed to achieve the same consistency at a lower water-to-cement ratio. For OPC, the addition of WRAs appeared to improve the both short- and long-term performance of CPB samples. However, only polycarboxylate-based superplasticiser produced the desired 28-day strength of > or = 0.7 MPa when PCC was used as the binder. These findings suggest that WRAs can be suitably exploited for CPB of sulphide-rich tailings to improve the strength and stability in short and long terms allowing to reduce binder costs in a CPB plant. PMID:20382473

  15. Genetics, surnames, grandparents' nationalities, and ethnic admixture in Southern Brazil: Do the patterns of variation coincide?

    Directory of Open Access Journals (Sweden)

    Dornelles C.L.

    1999-01-01

    Full Text Available A total of 2,708 individuals from the European-derived population of Rio Grande do Sul, divided into seven mesoregions, and of 226 individuals of similar origin from Santa Catarina were studied. Seventeen protein genetic systems, as well as grandparents' nationalities, individuals' surnames, and interethnic admixture were investigated. The alleles which presented the highest and lowest differences were GLO1*2 (16% and PGD*A (2%, respectively, but in general no significant genetic differences were found among mesoregions. The values observed were generally those expected for individuals of European descent, with the largest difference being a lower prevalence (34-39% of P*1. Significant heterogeneity among mesoregions was observed for the other variables considered, and was consistent with historical records. The Amerindian contribution to the gene pool of European-derived subjects in Rio Grande do Sul was estimated to be as high as 11%. Based on the four data sets, the most general finding was a tendency for a northeast-southwest separation of the populations studied. Seven significant phenotype associations between systems were observed at the 5% level (three at the 0.1% level. Of the latter, the two most interesting (since they were also observed in other studies were MNSs/Duffy and Rh/ACP.

  16. PERFORMANCE OF MICROWAVE INCINARATED RICE HUSK ASH AND USED ENGINE OIL AS A GREEN CONCRETE ADMIXTURES

    Directory of Open Access Journals (Sweden)

    B. SALMIA

    2015-12-01

    Full Text Available The utilization of waste materials in the construction industry is a novel approach let alone if these materials can further enhance the durability of the structures. Amongst the waste materials identified to be incorporated in this study is Rice Husk Ash (RHA and Used Engine Oil (UEO. Productions of these waste materials are colossal with annual volume of 1.35 billion gallon and 40 million tons of used engine oil and rice husk respectively. The main aim of this research is to establish the effects of these two waste materials (as ingredients in concrete. The rice husk was burn using microwave incinerator to produce better quality of Microwave Incinerated Rice Husk Ash (MIRHA. The pozzolanic reactivity of MIRHA helped to enhance concrete durability. The used engine oil acted as an admixture that improved the fresh state of the concrete. Workability, entrained air and compressive strength tests were conducted and the result showed that the concrete illustrated better performance compared to control sample in terms of workability, air contain and compressive strength.

  17. Efficiency of the coherent biexciton admixture mechanism for multiple exciton generation in InAs nanocrystals

    International Nuclear Information System (INIS)

    We study the coherent mixing between two-particle (single exciton) and four-particle (biexciton) states of a semiconductor nanocrystal resulting from the Coulomb coupling between states with different numbers of electron-hole pairs. Using a simple model of the nanocrystal wave functions and an envelope function approach, we estimate the efficiency of the multiple exciton generation (MEG) process resulting from such coherent admixture mechanism, including all the relevant states in a very broad energy interval. We show that in a typical ensemble of nanocrystals with an average radius of 3nm, the onset of the MEG process appears about 1 eV above the lower edge of the biexciton density of states. This is due to the angular momentum conservation that imposes selection rules and limits the available MEG pathways, thus taking over the role of momentum conservation that hinders this process in bulk. The efficiency of the MEG process reaches 50% for photon energies around 5 eV. The MEG onset shifts to lower energies and therefore the efficiency increases in a certain energy range as the radius grows. The energy dependence of the MEG efficiency differs considerably between ensembles with small and large inhomogeneity of nanocrystal sizes. (paper)

  18. Genetic structure of marine Borrelia garinii and population admixture with the terrestrial cycle of Lyme borreliosis.

    Science.gov (United States)

    Gómez-Díaz, Elena; Boulinier, Thierry; Sertour, Natacha; Cornet, Muriel; Ferquel, Elisabeth; McCoy, Karen D

    2011-09-01

    Despite the importance of population structure for the epidemiology of pathogenic bacteria, the spatial and ecological heterogeneity of these populations is often poorly characterized. Here, we investigated the genetic diversity and population structure of the Lyme borreliosis (LB) spirochaete Borrelia garinii in its marine cycle involving colonial seabirds and different host races of the seabird tick Ixodes uriae. Multilocus sequence analyses (MLSA) on eight chromosomal and two plasmid loci (ospA and ospC) indicate that B. garinii circulating in the marine system is highly diverse. Microevolution in marine B. garinii seems to be mainly clonal, but recombination and selection do occur. Sequence types were not evenly distributed among geographic regions, with substantial population subdivision between Atlantic and Pacific Ocean basins. However, no geographic structuring was evident within regions. Results of selection analyses and phylogenetic discordance between chromosomal and plasmid loci indicate adaptive evolution is likely occurring in this system, but no pattern of host or vector-associated divergence was found. Recombination analyses showed evidence for population admixture between terrestrial and marine strains, suggesting that LB spirochaetes are exchanged between these enzootic cycles. Importantly, our results highlight the need to explicitly consider the marine system for a complete understanding of the evolutionary ecology and global epidemiology of Lyme borreliosis. PMID:21651685

  19. Use of admixtures in organic-contaminated cement-clay pastes.

    Science.gov (United States)

    Gallo Stampino, Paola; Zampori, Luca; Dotelli, Giovanni; Meloni, Paola; Sora, Isabella Natali; Pelosato, Renato

    2009-01-30

    In this work microstructure, porosity and hydration degree of cement-based solidified/stabilized wasteforms were studied before assessing their leaching behaviour. 2-Chloroaniline was chosen as a model liquid organic pollutant and included into cement pastes, which were also modified with different admixtures for concrete: a superplasticizer based on acrylic-modified polymer, a synthetic rubber latex and a waterproofing agent. An organoclay, modified with an ammonium quaternary salt (benzyl-dimethyl-tallowammonium, BDMTA), was added to the pastes as pre-sorbent agent of the organic matter. All the samples were dried up to constant weight in order to stop the hydration process at different times during the first 28 days of curing, typically, after 1 day (1d), 7 days (7d) and 28 days. Then, the microstructure of the hardened cement-clay pastes was investigated by powder X-ray diffraction (XRD). The hydration degree and porosity were studied by thermal analysis (TG/DTA) and mercury intrusion porosimetry (MIP), respectively. For samples cured for 28 days a short-term leach test set by Italian regulation for industrial waste recycling (D.M. 5 February 1998) was performed. The best results showed a 5% release of the total initial amount of organic pollutant. PMID:18514398

  20. Search for an admixture of sterile neutrino in the electron spectrum from tritium $\\beta$-decay

    CERN Document Server

    Abdurashitov, D; Likhovid, N; Lokhov, A; Tkachev, I; Yants, V

    2014-01-01

    We propose an experiment intended for search for an admixture of sterile neutrino with mass m$_s$ in the range of 1-8 keV that may be detected as specific distortion of the electron energy spectrum during tritium decay. The distortion is spread over large part of the spectrum so to reveal it one can use a detector with relatively poor (near 10-15%) energy resolution. A classic proportional counter is a simple natural choice for a tritium $\\beta$-decay detector. The method we are proposing is original in two respects. First, the counter is produced as a whole from fully-fused quartz tube allowing to measure current pulse directly from anode while providing high stability for a long time. Second, a modern digital acquisition technique can be used in measurements at ultrahigh count rate - up to 10$^6$ Hz. As a result an energy spectrum of tritium electrons containing up to 10$^{12}$ counts may be collected in a month of live time measurements. Due to high statistics an upper limit down to 10$^{-3}$..10$^{-5}$ ca...

  1. USE OF CERTAIN ADMIXTURES IN THE CONSTRUCTION OF PAVEMENT ON EXPANSIVE CLAYEY SUBGRADES

    Directory of Open Access Journals (Sweden)

    D.NEERAJA,

    2010-11-01

    Full Text Available Due to rapid industrialization throughout the world, the production of huge quantity of produced waste materials creates not only the environmental problem but also the depositional hazards. Many procedures have been developed to improve the mechanical properties of soil by incorporating a wide range of stabilizing agents, additives and conditioners. In this paper, an attempt has been made to utilize industrial wastes like Rice Husk Ash (RHA, Fly Ash (FA and Ground Granulated Blast furnace Slag (GGBS as stabilizing agents. In addition to these, Lime was also added as stabilizing agent. The effect of Lime, RHA, FA and GGBS on certain properties of soil such as Optimum moisture content (OMC, Maximum Dry Density(MDD, Unconfined Compressive Strength (UCS and California Bearing Ratio (CBR has been studied. It has been established by experiments conducted on the samples that there is a maximum change in the properties with addition of lime up to 5%, RHA and GGBS up to 15% per cent and FA up to 20%. Of all the admixtures, Lime shows considerable increase in strength characteristics at an optimum lime content of 5% which gave maximum.

  2. Genetics, surnames, grandparents' nationalities, and ethnic admixture in Southern Brazil: Do the patterns of variation coincide?

    Directory of Open Access Journals (Sweden)

    C.L. Dornelles

    1999-06-01

    Full Text Available A total of 2,708 individuals from the European-derived population of Rio Grande do Sul, divided into seven mesoregions, and of 226 individuals of similar origin from Santa Catarina were studied. Seventeen protein genetic systems, as well as grandparents' nationalities, individuals' surnames, and interethnic admixture were investigated. The alleles which presented the highest and lowest differences were GLO1*2 (16% and PGD*A (2%, respectively, but in general no significant genetic differences were found among mesoregions. The values observed were generally those expected for individuals of European descent, with the largest difference being a lower prevalence (34-39% of P*1. Significant heterogeneity among mesoregions was observed for the other variables considered, and was consistent with historical records. The Amerindian contribution to the gene pool of European-derived subjects in Rio Grande do Sul was estimated to be as high as 11%. Based on the four data sets, the most general finding was a tendency for a northeast-southwest separation of the populations studied. Seven significant phenotype associations between systems were observed at the 5% level (three at the 0.1% level. Of the latter, the two most interesting (since they were also observed in other studies were MNSs/Duffy and Rh/ACP.

  3. Mechanical performance and ultrasonic properties of cemented gangue backfill with admixture of fly ash.

    Science.gov (United States)

    Wu, Di; Zhang, Yongliang; Liu, Yucheng

    2016-01-01

    Cemented gangue backfill (CGB) is prepared by mixing cement, coal gangue and water. Fly ash from the combustion of coal is commonly utilized as admixture to improve the mechanical performance and fluidity of CGB, as well as to reduce cost of preparing CGB. Uniaxial compressive strength (UCS) is one of the most commonly used indicators for evaluating the mechanical performance of CGB. Ultrasonic testing, which is a non-destructive measurement, can also be applied to determine the mechanical properties of cementitious materials such as CGB. So this paper investigates the UCS and ultrasonic pulse velocity (UPV) of CGB prepared at different fly ash dosage (19, 20 and 21 wt.%) and solid content (76.5, 77.5 and 78.5 wt.%), versus curing periods of 3-28 days. The UCS and UPV values of CGB increase with increasing fly ash dosage and solid content. In order to find out the correlation between the UCS and UPV values of CGB, different types (linear, logarithmic, exponential and power) of curve fitting are conducted on the CGB samples made at different solid content. An exponential relationship with the correlation coefficient of 0.959 appears to exist between the UCS and UPV for CGB samples. This obtained exponential relationship is validated to be available by performing the t- and F- tests. The results acquired by this paper are capable of providing guidance for utilizing UPV test to estimate the strength of underground CGB structures. PMID:26320702

  4. Study Of Characteristics Strength of Concrete with Admixtures by Flexural and Disc Bending Test

    Directory of Open Access Journals (Sweden)

    Anant Kumar

    2014-08-01

    Full Text Available Concrete is widely used in structural engineering with its high compressive strength, low cost and abandoned raw material, but common concrete has some deficiency, such as shrinkage and cracking, low tensile strength and flexural strength, high brittleness, that restrict its applications. To overcome these deficiencies’ additional materials are added to improve the performance of the concrete. Super plasticizer is a chemical added to conventional concrete mix that makes the concrete more workable and it can be placed easily. The aim of this project work to study the characteristics strengths of concrete such as compressive strength, flexural strength, split tensile strength, diametric strength and tensile strength by disc bending test. For the experimental work normal concrete M 40 has to be prepared and characteristics strength such as compressive strength, tensile strength, and flexural strength have to be achieved. This strength has to be performed after 7 days and 28 days curing. After that in addition of super plasticizer the study of the strength have to be performed with various % of plasticizer such as 0.60% to 1.2 % by the weight of cement and study of strength of concrete have to be performed at 7 days and 28 days. A relative comparison of the strength of the concrete with addition of admixtures with normal concrete can be study.

  5. Performance of rice husk ash produced using a new technology as a mineral admixture in concrete

    International Nuclear Information System (INIS)

    This article investigates the use of a new technique for the controlled combustion of Egyptian rice husk to mitigate the environmental concerns associated with its uncontrolled burning and provide a supplementary cementing material for the local construction industry. The reactor used provides efficient combustion of rice husk in a short residency time via the suspension of processed particles by jets of a process air stream that is forced though stationary angled blades at high velocity. Investigations on the rice husk ash (RHA) thus produced included oxide analysis, X-ray diffraction, carbon content, grindability, water demand, pozzolanic activity index, surface area, and particle size distribution measurements. In addition, concrete mixtures incorporating various proportions of silica fume (SF) and Egyptian RHA (EG-RHA) produced at different combustion temperatures were made and compared. The workability, superplasticizer and air-entraining admixture requirements, and compressive strength at various ages of these concrete mixtures were evaluated, and their resistance to rapid chloride penetrability and deicing salt surface scaling were examined. Test results indicate that contrary to RHA produced using existing technology, the superplasticizer and air-entraining agent requirements did not increase drastically when the RHA developed in this study was used. Compressive strengths achieved by concrete mixtures incorporating the new RHA exceeded those of concretes containing similar proportions of SF. The resistance to surface scaling of RHA concrete was better than that of concrete containing similar proportions of SF. While the chloride penetrability was substantially decreased by RHA, it remained slightly higher than that achieved by SF concrete

  6. Coagulated silica - a-SiO2 admixture in cement paste

    Science.gov (United States)

    Pokorný, Jaroslav; Pavlíková, Milena; Záleská, Martina; Rovnaníková, Pavla; Pavlík, Zbyšek

    2016-07-01

    Amorphous silica (a-SiO2) in fine-grained form possesses a high pozzolanic activity which makes it a valuable component of blended binders in concrete production. The origin of a-SiO2 applied in cement-based composites is very diverse. SiO2 in amorphous form is present in various amounts in quite a few supplementary cementing materials (SCMs) being used as partial replacement of Portland cement. In this work, the applicability of a commercially produced coagulated silica powder as a partial replacement of Portland cement in cement paste mix design is investigated. Portland cement CEM I 42.5R produced according to the EU standard EN 197-1 is used as a reference binder. Coagulated silica is applied in dosages of 5 and 10 % by mass of cement. The water/binder ratio is kept constant in all the studied pastes. For the applied silica, specific surface area, density, loss on ignition, pozzolanic activity, chemical composition, and SiO2 amorphous phase content are determined. For the developed pastes on the basis of cement-silica blended binder, basic physical properties as bulk density, matrix density, and total open porosity are accessed. Pore size distribution is determined using MIP analysis. Initial and final setting times of fresh mixtures are measured by automatic Vicat apparatus. Effect of silica admixture on mechanical resistivity is evaluated using compressive strength, bending strength, and dynamic Young's modulus measurement. The obtained data gives evidence of a decreased workability of paste mixtures with silica, whereas the setting process is accelerated. On the other hand, reaction activity of silica with Portland cement minerals results in a slight decrease of porosity and improvement of mechanical resistivity of cement pastes containing a-SiO2.

  7. Turbulent Prandtl number in the A model of passive vector admixture

    Science.gov (United States)

    Jurčišinová, E.; Jurčišin, M.; Remecký, R.

    2016-03-01

    Using the field theoretic renormalization group technique in the second-order (two-loop) approximation the explicit expression for the turbulent vector Prandtl number in the framework of the general A model of passively advected vector field by the turbulent velocity field driven by the stochastic Navier-Stokes equation is found as the function of the spatial dimension d >2 . The behavior of the turbulent vector Prandtl number as the function of the spatial dimension d is investigated in detail especially for three physically important special cases, namely, for the passive advection of the magnetic field in a conductive turbulent environment in the framework of the kinematic MHD turbulence (A =1 ), for the passive admixture of a vector impurity by the Navier-Stokes turbulent flow (A =0 ), and for the model of linearized Navier-Stokes equation (A =-1 ). It is shown that the turbulent vector Prandtl number in the framework of the A =-1 model is exactly determined already in the one-loop approximation, i.e., that all higher-loop corrections vanish. At the same time, it is shown that it does not depend on spatial dimension d and is equal to 1. On the other hand, it is shown that the turbulent magnetic Prandtl number (A =1 ) and the turbulent vector Prandtl number in the model of a vector impurity (A =0 ), which are essentially different at the one-loop level of approximation, become very close to each other when the two-loop corrections are taken into account. It is shown that their relative difference is less than 5 % for all integer values of the spatial dimension d ≥3 . Obtained results demonstrate strong universality of diffusion processes of passively advected scalar and vector quantities in fully symmetric incompressible turbulent environments.

  8. Partial constriction in a glow discharge in argon with nitrogen admixture

    International Nuclear Information System (INIS)

    The constriction of the positive column of a glow discharge in argon with nitrogen admixture (0.02–1%) was studied. The discharge was maintained in a tube of 2.8 cm inner diameter and 75 cm length at intermediate pressures (several tens of Torrs), at which the discharge constriction goes by a jump and the hysteresis effect is well pronounced. It was observed that the constriction begins near one of the electrodes and then the constricted region boundary propagates toward the other electrode. The reverse transition occurs in a similar way. The transition time in Ar : N2 mixtures appears to be essentially longer (up to 1 s) than that in pure argon. By varying the power supply voltage in the course of the transition, the boundary between the diffuse and constricted forms of the discharge could be stopped at some position between the electrodes. Such a partially constricted discharge (PCD) is stable and can exist for a long time. A PCD at various locations of the boundary can be formed, different locations being realized at different discharge voltages but at the same discharge current. This corresponds to a vertical segment in the voltage–current characteristic curve. It was found that this segment lies inside the hysteresis loop and connects two branches of the conventional I–V characteristic measured without affecting the discharge during the diffuse-to-constricted or reverse transitions. Plasma parameters in the diffuse and constricted positive columns are estimated and ionization mechanisms are analyzed. The possible reasons for the low velocity of the constriction front in Ar : N2 mixtures and the mechanisms of the stabilization of the PCD are also discussed. (paper)

  9. Combination of admixtures to improve the robustness of high-volume fly ash concrete in hot weather[ACI SP-239

    Energy Technology Data Exchange (ETDEWEB)

    Nkinamubanzi, P.C. [Natural Resources Canada, Ottawa, ON (Canada). CANMET International Centre for Sustainable Development of Cement and Concrete]|[American Concrete Inst. Farmington Hills, MI (United States); Bhattacharya, A.; Sharma, A. [Hindustan Construction Co., Mumbai (India)

    2006-07-01

    A precise admixtures system is needed when using high-volume fly ash concrete as fresh concrete occasionally undergoes rapid slump loss after mixing, which can cause problems with casting, pumping and finishing of the concrete in hot weather. This paper provided details of a study conducted to implement high-volume fly ash concrete technology in India. Different families of admixtures were investigated to determine their water reduction capacities. A set-retarding admixture was used in some of the concrete mixtures in order to determine its efficacy. An Indian Portland cement was used to create a total of 22 different concrete mixtures. Four different fly ashes were used to replace portions of the concrete. The slump of the fresh concrete mixture was monitored for 2 to 3 hours. Unit weight and temperature of the concrete was measured. Specimens were cast in steel moulds in order to determine the compressive strength and unit weight of the hardened concrete. The concretes were demoulded after 24 hours and cured in a water tank. Results of the study showed that 4 concrete mixtures showed good slump retention after 2 hours. The concretes were made using a combination of polycarboxylate-based admixtures from the naphthalene family. Concrete mixtures using admixtures made from sulfonated polymers also showed good slump resistance. Results showed that the selection of good combinations of admixtures can lead to excellent high volume fly ash concrete mixtures that are resistant to hot weather conditions. Exceptional results were achieved with concrete mixtures using a combination of polycarboxylates-based superplasticizers and sulfonated mid-range water-reducing admixtures. 7 refs., 8 tabs., 3 figs.

  10. Influence of shrinkage-reducing admixture on drying shrinkage and mechanical properties of high-performance concrete

    Institute of Scientific and Technical Information of China (English)

    Nguyen Quangphu; Jiang Linhua; Liu Jiaping; Tian Qian; Do Tienquan

    2008-01-01

    High-performance concrete (HPC) has specific performance advantages over conventional concrete in strength and durability. HPC mixtures are usually produced with water/binder mass ratios (mw/mB) in the range of 0.2-0.4, so volume changes of concrete as a result of drying, chemical reactions, and temperature change cannot be avoided. For these reasons, shrinkage and cracking are frequent phenomena. It is necessary to add some types of admixture for reduction of shrinkage and cracking of HPC. This study used a shrinkage-reducing admixture (SRA) for that purpose. Concrete was prepared with two different mw/mB(0.22 and 0.40) and four different mass fractions of SRA to binder (w(SRA) = 0%, 1%, 2%, and 4%). The mineral admixtures used for concrete mixes were: 25% fly ash (FA) and 25% slag by mass of binder for the mixture with mw/mB=0.40, and 15% silica fume (SF) and 25% FA for the mixture with mw/ma=0.22. Tests were conducted on 24 prismatic specimens, and shrinkage strains were measured through 120 days of drying. Compressive strength, splitting strength, and static modulus of elasticity were also determined. The results show that the SRA effectively reduces some mechanical properties of HPC. The reductions in compressive strength, splitting tensile strength, and elastic modulus of the concrete were 7%-24%, 9%-19%, and 5%-12%, respectively, after 90 days, compared to concrete mixtures without SRA. SRA can also help reduce drying shrinkage of concrete. The shrinkage strains of HPC with SRA were only as high as 41% of the average free shrinkage of concrete without SRA after 120 days of drying.

  11. Admixture mapping of serum vitamin D and parathyroid hormone concentrations in the African American-Diabetes Heart Study.

    Science.gov (United States)

    Palmer, Nicholette D; Divers, Jasmin; Lu, Lingyi; Register, Thomas C; Carr, J Jeffrey; Hicks, Pamela J; Smith, S Carrie; Xu, Jianzhao; Judd, Suzanne E; Irvin, Marguerite R; Gutierrez, Orlando M; Bowden, Donald W; Wagenknecht, Lynne E; Langefeld, Carl D; Freedman, Barry I

    2016-06-01

    Vitamin D and intact parathyroid hormone (iPTH) concentrations differ between individuals of African and European descent and may play a role in observed racial differences in bone mineral density (BMD). These findings suggest that mapping by admixture linkage disequilibrium (MALD) may be informative for identifying genetic variants contributing to these ethnic disparities. Admixture mapping was performed for serum 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, vitamin D-binding protein (VDBP), bioavailable vitamin D, and iPTH concentrations and computed tomography measured thoracic and lumbar vertebral volumetric BMD in 552 unrelated African Americans with type 2 diabetes from the African American-Diabetes Heart Study. Genotyping was performed using a custom Illumina ancestry informative marker (AIM) panel. For each AIM, the probability of inheriting 0, 1, or 2 copies of a European-derived allele was determined. Non-parametric linkage analysis was performed by testing for association between each AIM using these probabilities among phenotypes, accounting for global ancestry, age, and gender. Fine-mapping of MALD peaks was facilitated by genome-wide association study (GWAS) data. VDBP levels were significantly linked in proximity to the protein coding locus (rs7689609, LOD=11.05). Two loci exhibited significant linkage signals for 1,25-dihydroxyvitamin D on 13q21.2 (rs1622710, LOD=3.20) and 12q13.2 (rs11171526, LOD=3.10). iPTH was significantly linked on 9q31.3 (rs7854368, LOD=3.14). Fine-mapping with GWAS data revealed significant known (rs7041 with VDBP, P=1.38×10(-82)) and novel (rs12741813 and rs10863774 with VDBP, P<6.43×10(-5)) loci with plausible biological roles. Admixture mapping in combination with fine-mapping has focused efforts to identify loci contributing to ethnic differences in vitamin D-related traits. PMID:27032714

  12. Influence of shrinkage-reducing admixture on drying shrinkage and mechanical properties of high-performance concrete

    Directory of Open Access Journals (Sweden)

    Nguyen Quangphu

    2008-12-01

    Full Text Available Abstract: High-performance concrete (HPC has specific performance advantages over conventional concrete in strength and durability. HPC mixtures are usually produced with water/binder mass ratios (mW/mB in the range of 0.2-0.4, so volume changes of concrete as a result of drying, chemical reactions, and temperature change cannot be avoided. For these reasons, shrinkage and cracking are frequent phenomena. It is necessary to add some types of admixture for reduction of shrinkage and cracking of HPC. This study used a shrinkage-reducing admixture (SRA for that purpose. Concrete was prepared with two different mW/mB (0.22 and 0.40 and four different mass fractions of SRA to binder (w(SRA = 0%, 1%, 2%, and 4%. The mineral admixtures used for concrete mixes were: 25% fly ash (FA and 25% slag by mass of binder for the mixture with mW/mB = 0.40, and 15% silica fume (SF and 25% FA for the mixture with mW/mB = 0.22. Tests were conducted on 24 prismatic specimens, and shrinkage strains were measured through 120 days of drying. Compressive strength, splitting strength, and static modulus of elasticity were also determined. The results show that the SRA effectively reduces some mechanical properties of HPC. The reductions in compressive strength, splitting tensile strength, and elastic modulus of the concrete were 7%-24%, 9%-19%, and 5%-12%, respectively, after 90 days, compared to concrete mixtures without SRA. SRA can also help reduce drying shrinkage of concrete. The shrinkage strains of HPC with SRA were only as high as 41% of the average free shrinkage of concrete without SRA after 120 days of drying.

  13. Influence of Air Temperature on the Performance of Different Water-Reducing Admixtures with Respect to the Properties of Fresh and Hardened Mortar

    Directory of Open Access Journals (Sweden)

    Wilson Ricardo Leal Silva

    2010-01-01

    Full Text Available The performance of water-reducing admixtures used in concrete is affected by the weather conditions to which the concrete mixture is exposed. The most used WRAs are lignosulfonate, naphthalene, and polycarboxylate. However, they react differently to weather conditions, especially to air temperature. Therefore, it can be useful to evaluate how temperature affects admixture performance. In this study, the performance of three admixtures (naphthalene, lignosulfonate, and polycarboxylate was evaluated at 15, 25, and 35°C by means of the flow table test, mixture air content, and compressive strength. Moreover, mixture temperature was monitored and time-temperature curves were plotted in order to assess whether the admixtures affected cement hydration reactions at different temperatures. The final results indicate that an increase in temperature leads to an increase in saturation dosage; lignosulfonate had the most pronounced retarding effect, followed by polycarboxylate, and finally, naphthalene, and considering the weather conditions in the area where the study was carried, the final finding would be that the naphthalene-based admixture had the best performance.

  14. Low-frequency resonances of the refractive index in weakly ionized plasma with an admixture of dust

    International Nuclear Information System (INIS)

    The propagation of low-frequency electromagnetic waves along the magnetic field in weakly ionized plasma with an admixture of dust is studied in the framework of the Hall magnetohydrodynamics. Explicit expressions for the coefficients of magnetic field diffusion in plasma are derived. The resonance of the refractive index is found to occur for either right- or left-hand polarized waves. A quantitative criterion is obtained that allows one to determine the polarization of waves that experience resonance at given plasma parameters. The physical mechanism of the resonance is discussed, and the obtained results are compared with the available literature data

  15. Structural Investigations of Portland Cement Components, Hydration, and Effects of Admixtures by Solid-State NMR Spectroscopy

    DEFF Research Database (Denmark)

    Skibsted, Jørgen Bengaard; Andersen, Morten D.; Jakobsen, Hans Jørgen

    2006-01-01

    Solid-state, magic-angle spinning (MAS) NMR spectroscopy represents a valuable tool for structural investigations on the nanoscale of the most important phases in anhydrous and hydrated Portland cements and of various admixtures. This is primarily due to the fact that the method reflects the first...... have been investigated in detail by 29Si and 27Al MAS NMR where the combination of the results for these spin-nuclei provides important information on the degree of Al-incorporation in the C-S-H structure and of the average chain lengths of tetrahedral SiO4 and AlO4 units. This presentation will...

  16. Genome-wide scan of 29,141 African Americans finds no evidence of selection since admixture

    OpenAIRE

    Bhatia, Gaurav; Tandon, Arti; Aldrich, Melinda C.; Ambrosone, Christine B.; Amos, Christopher; Bandera, Elisa V.; Berndt, Sonja I.; Bernstein, Leslie; William J Blot; Bock, Cathryn H.; Caporaso, Neil; Casey, Graham; Deming, Sandra L.; Diver, W Ryan; Gapstur, Susan M

    2013-01-01

    We scanned through the genomes of 29,141 African Americans, searching for loci where the average proportion of African ancestry deviates significantly from the genome-wide average. We failed to find any genome-wide significant deviations, and conclude that any selection in African Americans since admixture is sufficiently weak that it falls below the threshold of our power to detect it using a large sample size. These results stand in contrast to the findings of a recent study of selection in...

  17. Influence of shrinkage-reducing admixture on drying shrinkage and mechanical properties of high-performance concrete

    OpenAIRE

    Nguyen Quangphu; Jiang Linhua; Liu Jiaping; Tian Qian; Do Tienquan

    2008-01-01

    Abstract: High-performance concrete (HPC) has specific performance advantages over conventional concrete in strength and durability. HPC mixtures are usually produced with water/binder mass ratios (mW/mB) in the range of 0.2-0.4, so volume changes of concrete as a result of drying, chemical reactions, and temperature change cannot be avoided. For these reasons, shrinkage and cracking are frequent phenomena. It is necessary to add some types of admixture for reduction of shrinkage and crac...

  18. Admixture in Latin America: geographic structure, phenotypic diversity and self-perception of ancestry based on 7,342 individuals.

    Directory of Open Access Journals (Sweden)

    Andrés Ruiz-Linares

    2014-09-01

    Full Text Available The current genetic makeup of Latin America has been shaped by a history of extensive admixture between Africans, Europeans and Native Americans, a process taking place within the context of extensive geographic and social stratification. We estimated individual ancestry proportions in a sample of 7,342 subjects ascertained in five countries (Brazil, Chile, Colombia, México and Perú. These individuals were also characterized for a range of physical appearance traits and for self-perception of ancestry. The geographic distribution of admixture proportions in this sample reveals extensive population structure, illustrating the continuing impact of demographic history on the genetic diversity of Latin America. Significant ancestry effects were detected for most phenotypes studied. However, ancestry generally explains only a modest proportion of total phenotypic variation. Genetically estimated and self-perceived ancestry correlate significantly, but certain physical attributes have a strong impact on self-perception and bias self-perception of ancestry relative to genetically estimated ancestry.

  19. Gene admixture in ethnic populations in upper part of Silk Road revealed by mtDNA polymorphism

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    To evaluate the gene admixture on the current genetic landscape in Gansu Corridor (GC) in China, the upper part of the ancient Silk Road which connects the Eastern and Central Asia, we examined mitochondrial DNA (mtDNA) polymorphisms of five ethnic populations in this study. Using PCR-RFLP and sequencing, we analyzed mtDNA haplotypes in 242 unrelated samples in three ethnic populations from the GC region and two ethnic populations from the adjacent Xinjiang Uygur Autonomous Region of China. We analyzed the data in comparison with the previously reported data from Eastern, Central and Western Asia and Europe. We found that both European-specific haplogroups and Eastern Asian-specific haplogroups exist in the Gansu Corridor populations, while a modest matrilineal gene flow from Europeans to this region was revealed. The Gansu Corridor populations are genetically located between Eastern Asians and Central Asians, both of who contributed significantly to the maternal lineages of the GC populations. This study made the landscape of the gene flow and admixture along the Silk Road from Europe, through Central Asia, to the upper part of the Silk Road more complete.

  20. Identification of admixture for pelletization and strength enhancement of sintered coal pond ash aggregate through statistically designed experiments

    International Nuclear Information System (INIS)

    Highlights: • Sintered aggregate using pond ash from lignite and bituminous coal source. • Identification of admixtures and its dosage through design of experiments. • Clay, bentonite and kaolinite as binders enhance the strength of aggregate. • Use of calcium hydroxide with clay binder enhanced pelletization efficiency. • Use of borax with clay binders enhanced the strength of aggregate. - Abstract: Statistically designed experiments using Response Surface Methodology have been undertaken to identify the parameters influencing manufacturing process and properties of aggregate using coal pond ash (generated from bituminous and lignite coal sources). Based on the preliminary studies, Ca(OH)2 and borax have been identified as pelletization and strength enhancing admixture respectively. Pelletization efficiency of bituminous and lignite pond ash increased with an increase in binder and Ca(OH)2 dosage to 20–98% and 50–98% respectively, with proportionate quantity of water. Sintering has been used as a hardening method with temperature range of 900 °C and 1100 °C for a duration range of 45–120 min. Phase composition and sintered microstructure of aggregate has been reported using X-ray diffraction and scanning electron microscopy respectively. The ten percent fines value of aggregate with clay binder was 5.5 tonne as against a value of 4.5 tonne with aggregate with bentonite binder. Among the binders studied, bentonite resulted in high volume utilization of pond ash, i.e. up to 88%

  1. Influence of admixture components on CYP2C9*2 allele frequency in eight indigenous populations from Northwest Mexico.

    Science.gov (United States)

    Sosa-Macías, M; Lazalde-Ramos, B P; Galaviz-Hernández, C; Rangel-Villalobos, H; Salazar-Flores, J; Martínez-Sevilla, V M; Martínez-Fierro, M L; Dorado, P; Wong, M L; Licinio, J; LLerena, A

    2013-12-01

    We previously documented the lowest frequency of CYP2C9*2 in Mexican indigenous Tepehuanos followed by Mestizos and Mexican-Americans populations, suggesting a negative correlation between the CYP2C9*2 frequency and the degree of Asian ancestry in indigenous Americans. We determined the influence of ethnic admixture components on the CYP2C9 allele distribution in 505 Amerindian from eight indigenous populations through genotyping CYP2C9*2, *3 and *6 alleles by real-time PCR and molecular evaluation of ancestry. The frequencies for CYP2C9*2 were 0.026 in Seris and 0.057 in Mayos, being higher than in Asians (P<0.001). CYP2C9*3 was found in Tarahumaras (0.104), Mayos (0.091), Tepehuanos (0.075), Guarijíos (0.067), Huicholes (0.033) and Coras (0.037), with East Asians having lower frequencies than the former three groups (P<0.001). CYP2C9*6 was not found. The frequency of CYP2C9*2 was lower in Amerindians than in European populations, and higher than their Asian ancestors. The presence of this allele in ethnic groups in Mexico can be explained by European admixture. PMID:23358499

  2. Genetic dating indicates that the Asian–Papuan admixture through Eastern Indonesia corresponds to the Austronesian expansion

    Science.gov (United States)

    Xu, Shuhua; Pugach, Irina; Stoneking, Mark; Kayser, Manfred; Jin, Li

    2012-01-01

    Although the Austronesian expansion had a major impact on the languages of Island Southeast Asia, controversy still exists over the genetic impact of this expansion. The coexistence of both Asian and Papuan genetic ancestry in Eastern Indonesia provides a unique opportunity to address this issue. Here, we estimate recombination breakpoints in admixed genomes based on genome-wide SNP data and date the genetic admixture between populations of Asian vs. Papuan ancestry in Eastern Indonesia. Analyses of two genome-wide datasets indicate an eastward progression of the Asian admixture signal in Eastern Indonesia beginning about 4,000–3,000 y ago, which is in excellent agreement with inferences based on Austronesian languages. The average rate of spread of Asian genes in Eastern Indonesia was about 0.9 km/y. Our results indicate that the Austronesian expansion had a strong genetic as well as linguistic impact on Island Southeast Asia, and they significantly advance our understanding of the biological origins of human populations in the Asia–Pacific region. PMID:22396590

  3. Genetic dating indicates that the Asian-Papuan admixture through Eastern Indonesia corresponds to the Austronesian expansion.

    Science.gov (United States)

    Xu, Shuhua; Pugach, Irina; Stoneking, Mark; Kayser, Manfred; Jin, Li

    2012-03-20

    Although the Austronesian expansion had a major impact on the languages of Island Southeast Asia, controversy still exists over the genetic impact of this expansion. The coexistence of both Asian and Papuan genetic ancestry in Eastern Indonesia provides a unique opportunity to address this issue. Here, we estimate recombination breakpoints in admixed genomes based on genome-wide SNP data and date the genetic admixture between populations of Asian vs. Papuan ancestry in Eastern Indonesia. Analyses of two genome-wide datasets indicate an eastward progression of the Asian admixture signal in Eastern Indonesia beginning about 4,000-3,000 y ago, which is in excellent agreement with inferences based on Austronesian languages. The average rate of spread of Asian genes in Eastern Indonesia was about 0.9 km/y. Our results indicate that the Austronesian expansion had a strong genetic as well as linguistic impact on Island Southeast Asia, and they significantly advance our understanding of the biological origins of human populations in the Asia-Pacific region. PMID:22396590

  4. Admixture in Latin America: Geographic Structure, Phenotypic Diversity and Self-Perception of Ancestry Based on 7,342 Individuals

    Science.gov (United States)

    Ruiz-Linares, Andrés; Adhikari, Kaustubh; Acuña-Alonzo, Victor; Quinto-Sanchez, Mirsha; Jaramillo, Claudia; Arias, William; Fuentes, Macarena; Pizarro, María; Everardo, Paola; de Avila, Francisco; Gómez-Valdés, Jorge; León-Mimila, Paola; Hunemeier, Tábita; Ramallo, Virginia; Silva de Cerqueira, Caio C.; Burley, Mari-Wyn; Konca, Esra; de Oliveira, Marcelo Zagonel; Veronez, Mauricio Roberto; Rubio-Codina, Marta; Attanasio, Orazio; Gibbon, Sahra; Ray, Nicolas; Gallo, Carla; Poletti, Giovanni; Rosique, Javier; Schuler-Faccini, Lavinia; Salzano, Francisco M.; Bortolini, Maria-Cátira; Canizales-Quinteros, Samuel; Rothhammer, Francisco; Bedoya, Gabriel; Balding, David; Gonzalez-José, Rolando

    2014-01-01

    The current genetic makeup of Latin America has been shaped by a history of extensive admixture between Africans, Europeans and Native Americans, a process taking place within the context of extensive geographic and social stratification. We estimated individual ancestry proportions in a sample of 7,342 subjects ascertained in five countries (Brazil, Chile, Colombia, México and Perú). These individuals were also characterized for a range of physical appearance traits and for self-perception of ancestry. The geographic distribution of admixture proportions in this sample reveals extensive population structure, illustrating the continuing impact of demographic history on the genetic diversity of Latin America. Significant ancestry effects were detected for most phenotypes studied. However, ancestry generally explains only a modest proportion of total phenotypic variation. Genetically estimated and self-perceived ancestry correlate significantly, but certain physical attributes have a strong impact on self-perception and bias self-perception of ancestry relative to genetically estimated ancestry. PMID:25254375

  5. Winning the invasion roulette: escapes from fish farms increase admixture and facilitate establishment of non-native rainbow trout.

    Science.gov (United States)

    Consuegra, Sofia; Phillips, Nia; Gajardo, Gonzalo; de Leaniz, Carlos Garcia

    2011-09-01

    Aquaculture is a major source of invasive aquatic species, despite the fact that cultured organisms often have low genetic diversity and tend to be maladapted to survive in the wild. Yet, to what extent aquaculture escapees become established by means of high propagule pressure and multiple origins is not clear. We analysed the genetic diversity of 15 established populations and four farmed stocks of non-native rainbow trout in Chile, a species first introduced for recreational fishing around 1900, but which has in recent decades escaped in large numbers from fish farms and become widespread. Aquaculture propagule pressure was a good predictor of the incidence of farm escapees, which represented 16% of all free-ranging rainbow trout and were present in 80% of the study rivers. Hybrids between farm escapes and established trout were present in all rivers at frequencies ranging between 7 and 69%, and population admixture was positively correlated with genetic diversity. We suggest that non-native salmonids introduced into the Southern Hemisphere could benefit from admixture because local adaptations may not have yet developed, and there may be initially little fitness loss resulting from outbreeding depression. PMID:25568013

  6. Effects of (V + A)-, S-, T-interaction admixtures and of a time reversal invariance violation on the first-forbidden beta-decay of RaE

    International Nuclear Information System (INIS)

    The shape factor and the electron longitudinal polarization of RaE have been calculated under the assumption of (V + A)-, S-, T-interaction admixtures. In addition the influence of a time reversal invariance violation has been considered. It is shown that the effect of (V + A) admixtures on the electron longitudinal polarization is enhanced by two orders of magnitude compared to the case of allowed transitions. Such an effect is also observed for the shape factor. It is also demonstrated that a time reversal invariance violation also affects the observables mentioned above. (orig.)

  7. Admixture Mapping in Lupus Identifies Multiple Functional Variants within IFIH1 Associated with Apoptosis, Inflammation, and Autoantibody Production

    Science.gov (United States)

    Looger, Loren L.; Han, Shizhong; Kim-Howard, Xana; Glenn, Stuart; Adler, Adam; Kelly, Jennifer A.; Niewold, Timothy B.; Gilkeson, Gary S.; Brown, Elizabeth E.; Alarcón, Graciela S.; Edberg, Jeffrey C.; Petri, Michelle; Ramsey-Goldman, Rosalind; Reveille, John D.; Vilá, Luis M.; Freedman, Barry I.; Tsao, Betty P.; Criswell, Lindsey A.; Jacob, Chaim O.; Moore, Jason H.; Vyse, Timothy J.; Langefeld, Carl L.; Guthridge, Joel M.; Gaffney, Patrick M.; Moser, Kathy L.; Scofield, R. Hal; Alarcón-Riquelme, Marta E.; Williams, Scott M.; Merrill, Joan T.; James, Judith A.; Kaufman, Kenneth M.; Kimberly, Robert P.; Harley, John B.; Nath, Swapan K.

    2013-01-01

    Systemic lupus erythematosus (SLE) is an inflammatory autoimmune disease with a strong genetic component. African-Americans (AA) are at increased risk of SLE, but the genetic basis of this risk is largely unknown. To identify causal variants in SLE loci in AA, we performed admixture mapping followed by fine mapping in AA and European-Americans (EA). Through genome-wide admixture mapping in AA, we identified a strong SLE susceptibility locus at 2q22–24 (LOD = 6.28), and the admixture signal is associated with the European ancestry (ancestry risk ratio ∼1.5). Large-scale genotypic analysis on 19,726 individuals of African and European ancestry revealed three independently associated variants in the IFIH1 gene: an intronic variant, rs13023380 [Pmeta = 5.20×10−14; odds ratio, 95% confidence interval = 0.82 (0.78–0.87)], and two missense variants, rs1990760 (Ala946Thr) [Pmeta = 3.08×10−7; 0.88 (0.84–0.93)] and rs10930046 (Arg460His) [Pdom = 1.16×10−8; 0.70 (0.62–0.79)]. Both missense variants produced dramatic phenotypic changes in apoptosis and inflammation-related gene expression. We experimentally validated function of the intronic SNP by DNA electrophoresis, protein identification, and in vitro protein binding assays. DNA carrying the intronic risk allele rs13023380 showed reduced binding efficiency to a cellular protein complex including nucleolin and lupus autoantigen Ku70/80, and showed reduced transcriptional activity in vivo. Thus, in SLE patients, genetic susceptibility could create a biochemical imbalance that dysregulates nucleolin, Ku70/80, or other nucleic acid regulatory proteins. This could promote antibody hypermutation and auto-antibody generation, further destabilizing the cellular network. Together with molecular modeling, our results establish a distinct role for IFIH1 in apoptosis, inflammation, and autoantibody production, and explain the molecular basis of these three risk alleles for SLE pathogenesis. PMID

  8. Admixture mapping in lupus identifies multiple functional variants within IFIH1 associated with apoptosis, inflammation, and autoantibody production.

    Directory of Open Access Journals (Sweden)

    Julio E Molineros

    Full Text Available Systemic lupus erythematosus (SLE is an inflammatory autoimmune disease with a strong genetic component. African-Americans (AA are at increased risk of SLE, but the genetic basis of this risk is largely unknown. To identify causal variants in SLE loci in AA, we performed admixture mapping followed by fine mapping in AA and European-Americans (EA. Through genome-wide admixture mapping in AA, we identified a strong SLE susceptibility locus at 2q22-24 (LOD=6.28, and the admixture signal is associated with the European ancestry (ancestry risk ratio ~1.5. Large-scale genotypic analysis on 19,726 individuals of African and European ancestry revealed three independently associated variants in the IFIH1 gene: an intronic variant, rs13023380 [P(meta = 5.20×10(-14; odds ratio, 95% confidence interval = 0.82 (0.78-0.87], and two missense variants, rs1990760 (Ala946Thr [P(meta = 3.08×10(-7; 0.88 (0.84-0.93] and rs10930046 (Arg460His [P(dom = 1.16×10(-8; 0.70 (0.62-0.79]. Both missense variants produced dramatic phenotypic changes in apoptosis and inflammation-related gene expression. We experimentally validated function of the intronic SNP by DNA electrophoresis, protein identification, and in vitro protein binding assays. DNA carrying the intronic risk allele rs13023380 showed reduced binding efficiency to a cellular protein complex including nucleolin and lupus autoantigen Ku70/80, and showed reduced transcriptional activity in vivo. Thus, in SLE patients, genetic susceptibility could create a biochemical imbalance that dysregulates nucleolin, Ku70/80, or other nucleic acid regulatory proteins. This could promote antibody hypermutation and auto-antibody generation, further destabilizing the cellular network. Together with molecular modeling, our results establish a distinct role for IFIH1 in apoptosis, inflammation, and autoantibody production, and explain the molecular basis of these three risk alleles for SLE pathogenesis.

  9. Chemical, physical and engineering characterization of candidate backfill clays and clay admixtures for a nuclear waste repository-Part I

    International Nuclear Information System (INIS)

    Fourteen Canadian clays and clay admixtures were subjected to simulated nuclear waste repository environments. The present work is concerned with the montmorillonite-dominant materials only. The montmorillonite-dominant samples showed significant leaching on interaction with deionized water. On heating the samples at 2000C for 500 hours, montmorillonites lost intermicellar water completely and acquired cusp-like to cylindrical morphologies. The loss of water and the morphological changes in montmorillonites significantly altered the engineering characteristics. Permeability, shrinkage limits, compactability and shear strength varied in response to the dominant exchange cation in the structure of montmorillonites and the presence of other mineral components in the materials. The synthetic granite water reacted with montmorillonites and led to changes in chemical and mineralogical compositions, crystalline state and engineering properties. 12 figures, 9 tables

  10. Survey and coping strategies for job stress of new nurses in pharmacy intravenous admixture service: a pilot study.

    Science.gov (United States)

    Wang, Feng-Shuang; Jin, Ou; Feng, Hua; Wang, Feng-Hua; Ren, Chun-Hui

    2015-01-01

    To survey the nurse stress and analyze stressors in new nurses from pharmacy intravenous admixture service (PIAS). A questionnaire survey referring to the revised stressor scale was carried out on 52 new nurses of PIAS in four hospitals in Harbin. The average stress score for all participants was 2.43±0.63, as medium level of stress. The stressors were classified into 6 categories: ensuring up-to-date knowledge of professional nursing skills, increased workload and work-time, interpersonal relationship, ensuring knowledge of equipments, attending educational programs, and decreased occupational demand. The most important stressors included fear of medical accident occurrence, fear of failure in performance assessment, fear of occupational injuries, feeling fatigue and lack of sleep. Considering the various kinds of stressors in the working places, it was necessary for managers' to use appropriate strategies to cope with the job stress in new nurses of PIAS. PMID:26770583

  11. Phylogeographic Analyses of American Black Bears (Ursus americanus) Suggest Four Glacial Refugia and Complex Patterns of Postglacial Admixture.

    Science.gov (United States)

    Puckett, Emily E; Etter, Paul D; Johnson, Eric A; Eggert, Lori S

    2015-09-01

    Studies of species with continental distributions continue to identify intraspecific lineages despite continuous habitat. Lineages may form due to isolation by distance, adaptation, divergence across barriers, or genetic drift following range expansion. We investigated lineage diversification and admixture within American black bears (Ursus americanus) across their range using 22 k single nucleotide polymorphisms and mitochondrial DNA sequences. We identified three subcontinental nuclear clusters which we further divided into nine geographic regions: Alaskan (Alaska-East), eastern (Central Interior Highlands, Great Lakes, Northeast, Southeast), and western (Alaska-West, West, Pacific Coast, Southwest). We estimated that the western cluster diverged 67 ka, before eastern and Alaskan divergence 31 ka; these divergence dates contrasted with those from the mitochondrial genome where clades A and B diverged 1.07 Ma, and clades A-east and A-west diverged 169 ka. We combined estimates of divergence timing with hindcast species distribution models to infer glacial refugia for the species in Beringia, Pacific Northwest, Southwest, and Southeast. Our results show a complex arrangement of admixture due to expansion out of multiple refugia. The delineation of the genomic population clusters was inconsistent with the ranges for 16 previously described subspecies. Ranges for U. a. pugnax and U. a. cinnamomum were concordant with admixed clusters, calling into question how to order taxa below the species level. Additionally, our finding that U. a. floridanus has not diverged from U. a. americanus also suggests that morphology and genetics should be reanalyzed to assess taxonomic designations relevant to the conservation management of the species. PMID:25989983

  12. Experimental Research on Polycarboxylic Slump-retaining Admixture%聚羧酸减水剂的试验研究

    Institute of Scientific and Technical Information of China (English)

    廖国胜; 艾涛; 肖煜; 潘会

    2014-01-01

    Adopting methyl allyl polyoxyethylene ether (TPEG)and unsaturated carboxylic acid throught REDOX system synthetize the polycarboxylic slump-retaining admixture.The impact factors were researched of temperature,re-action time,acid alcohol ratio,dosage of initiator and molecular regulator to the polycarboxylic superplasticizer with slump retaining.In the circumstance of n(AA)∶n(Itaconic acid)∶n(Thioglycolic acid)∶n(TPEG)=1.7∶0.23∶0.005∶1,m(initiator)∶m(TPEG)=0.20%,reaction time is 4 h and temperaure is 45 ℃,the admixture has the best performance.%采用甲基烯丙基聚氧乙烯醚(TPEG)与不饱和羧酸在氧化还原体系下合成聚羧酸减水剂。研究了反应温度、反应时间、单体与不饱和羧酸摩尔比(酸醚比)、引发剂用量及分子量调节剂用量对聚羧酸减水剂性能的影响。在n(AA)∶n(Itaconic acid)∶n(Thioglycolic acid)∶n(TPEG)=1.7∶0.23∶0.005∶1,m(initiator)∶m(TPEG)=0.20%、反应时间4 h、反应温度45℃时,聚羧酸减水剂各项性能最佳。

  13. Multispecies Outcomes of Sympatric Speciation after Admixture with the Source Population in Two Radiations of Nicaraguan Crater Lake Cichlids

    Science.gov (United States)

    Kautt, Andreas F.; Machado-Schiaffino, Gonzalo; Meyer, Axel

    2016-01-01

    The formation of species in the absence of geographic barriers (i.e. sympatric speciation) remains one of the most controversial topics in evolutionary biology. While theoretical models have shown that this most extreme case of primary divergence-with-gene-flow is possible, only a handful of accepted empirical examples exist. And even for the most convincing examples uncertainties remain; complex histories of isolation and secondary contact can make species falsely appear to have originated by sympatric speciation. This alternative scenario is notoriously difficult to rule out. Midas cichlids inhabiting small and remote crater lakes in Nicaragua are traditionally considered to be one of the best examples of sympatric speciation and lend themselves to test the different evolutionary scenarios that could lead to apparent sympatric speciation since the system is relatively small and the source populations known. Here we reconstruct the evolutionary history of two small-scale radiations of Midas cichlids inhabiting crater lakes Apoyo and Xiloá through a comprehensive genomic data set. We find no signs of differential admixture of any of the sympatric species in the respective radiations. Together with coalescent simulations of different demographic models our results support a scenario of speciation that was initiated in sympatry and does not result from secondary contact of already partly diverged populations. Furthermore, several species seem to have diverged simultaneously, making Midas cichlids an empirical example of multispecies outcomes of sympatric speciation. Importantly, however, the demographic models strongly support an admixture event from the source population into both crater lakes shortly before the onset of the radiations within the lakes. This opens the possibility that the formation of reproductive barriers involved in sympatric speciation was facilitated by genetic variants that evolved in a period of isolation between the initial founding

  14. Composts with and without wood ash admixture for the management of tropical acid soils: chemical, physical and microbiological effects

    Science.gov (United States)

    Bougnom, B. P.; Insam, H.; Etoa, F. X.

    2009-04-01

    Acid soils generally found in the tropics have a low pH, are poor in organic matter, deficient in Ca2+, Mg+, P, or Mo ; limited in mineralization, nitrification, nodulation, and mycorrhizal infection , suffer from Al or Mn toxicity. Within the framework aiming at using organic wastes and wood ash to overcome soil infertility in tropical acidic soils, a green house experiment was conducted with two acid soils collected from Cameroon (Ferralsol and Acrisol) and amended with three types of compost 3:1(W/W) containing 0 (K0), 8(K8) and 16% (K16) wood ash admixture respectively for two consecutive cycles of 100 days, during which soybean (Glycine max) was grown on the first, the second cycle was left as fallow. Generally the same trends of variation of the physico-chemical parameters were observed in both soils. Addition of organic wastes increased the pH electrical conductivity, soil organic matter, water holding capacity, total Carbone and total nitrogen as compared to the controls. The rate of nitrification highly increased posing the problem of possible leaching of nitrates in the ground water. The cations and micronutrients content followed the same trends. These changes leaded to an increase of the P availability and a decrease of Al toxicity. At the end of the second cycle, generally most of the different parameters slightly decreased except for the electrical conductivity. All composts passed a toxicity test, and the amended soils had significant better fresh and dried plant biomass, the Total nitrogen also significantly increased. Amended soils with K0 generally performed better than those amended with K8 and K16, thinking that their pH (closer to the neutrality) was responsible of these performances, all the parameters were significantly correlated to the pH. K8 and K16 performances could be performed by reducing the added quantities. The study of PCR-DGGE have shown a shift in the fungal and bacterial communities, Ammonia oxidizing bacteria community were

  15. Standard test method for determining effects of chemical admixtures on corrosion of embedded steel reinforcement in concrete exposed to chloride environments

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2007-01-01

    1.1 This test method covers a procedure for determining the effects of chemical admixtures on the corrosion of metals in concrete. This test method can be used to evaluate materials intended to inhibit chloride-induced corrosion of steel in concrete. It can also be used to evaluate the corrosivity of admixtures in a chloride environment. 1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  16. The isospin admixture of the ground state and the properties of the isobar analog resonances in medium and heavy mass nuclei

    Indian Academy of Sciences (India)

    D I Salmov; T Babacan; A Kücükbursa; S Ünlü; İ Maraṣ

    2006-06-01

    Within the framework of quasiparticle random phase approximation (QRPA), Pyatov–Salamov method [23] for the self-consistent determination of the isovector effective interaction strength parameter, restoring a broken isotopic symmetry for the nuclear part of the Hamiltonian, is used. The isospin admixtures in the ground state of the parent nucleus, and the isospin structure of the isobar analog resonance (IAR) state were investigated with the inclusion of the pairing correlations between nucleons for the medium and heavy mass regions: 80 < < 90, 102 < < 124, and 204 < < 214. It was determined that the influence of the pairing interaction between nucleons on the isospin admixtures in the ground state and the isospin structure of the IAR state is more pronounced for the light isotopes ( ≈ ) of the investigated nuclei.

  17. The peopling of São Tomé (Gulf of Guinea): origins of slave settlers and admixture with the Portuguese.

    Science.gov (United States)

    Tomás, Gil; Seco, Luísa; Seixas, Susana; Faustino, Paula; Lavinha, João; Rocha, Jorge

    2002-06-01

    The geographic origins of African slave settlers and the Portuguese genetic contribution to the population of São Tomé (Gulf of Guinea) were assessed through the analysis of beta-globin haplotypes in 44 chromosomes bearing the betaS allele and through the study of the genetic variation in eight autosomal markers (APOA1, AT3, FY, LPL, OCA2, RB1, Sb19.3, and GC) informative for admixture in a sample of 224 individuals. The observed betaS haplotype distribution (36.4% Bantu, 52.3% Benin, 4.5% Cameroon, 4.5% Senegal, and 2.3% atypical) is in accordance with the historical information on the major geographic sources of slave settlers of São Tomé, although it captures a more important contribution of Central-West Africa regions than previously anticipated. European admixture, estimated to be 10.7 +/- 0.9%, has created a considerable level of genetic structure, as indicated by the finding of significant linkage disequilibrium between 33% of unlinked marker loci pairs. Recent admixture was found to have an important contribution to these values, since removal of individuals with Portuguese or Cape Verdian parents or grandparents from the sample dropped the miscegenation level to 6.5 +/- 0.8% and reduced significant linkage disequilibrium to 11% of unlinked marker pairs. Taken together, these results indicate that the peopling of São Tomé might have provided one of the first examples of the combination of diverse African contributions and European admixture that emerged from the overseas population relocations promoted by the Atlantic slave trade. PMID:12180763

  18. Research status of mine tailings used as cement admixture%尾矿作水泥混合材的研究现状

    Institute of Scientific and Technical Information of China (English)

    谭明洋; 吕宪俊; 姜梅芬

    2015-01-01

    概述了近年来尾矿在水泥中的应用及研究现状,并据此提出了今后尾矿用作水泥混合材的研究方向。%Summarized the application status and the up-to-date progress of mine tailings used in cement,and further research topics for the application performance of cement admixtures were proposed accordingly.

  19. Northern range expansion of European populations of the wasp spider Argiope bruennichi is associated with global warming-correlated genetic admixture and population-specific temperature adaptations.

    Science.gov (United States)

    Krehenwinkel, Henrik; Tautz, Diethard

    2013-04-01

    Poleward range expansions are observed for an increasing number of species, which may be an effect of global warming during the past decades. However, it is still not clear in how far these expansions reflect simple geographical shifts of species ranges, or whether new genetic adaptations play a role as well. Here, we analyse the expansion of the wasp spider Argiope bruennichi into Northern Europe during the last century. We have used a range-wide sampling of contemporary populations and historical specimens from museums to trace the phylogeography and genetic changes associated with the range shift. Based on the analysis of mitochondrial, microsatellite and SNP markers, we observe a higher level of genetic diversity in the expanding populations, apparently due to admixture of formerly isolated lineages. Using reciprocal transplant experiments for testing overwintering tolerance, as well as temperature preference and tolerance tests in the laboratory, we find that the invading spiders have possibly shifted their temperature niche. This may be a key adaptation for survival in Northern latitudes. The museum samples allow a reconstruction of the invasion's genetic history. A first, small-scale range shift started around 1930, in parallel with the onset of global warming. A more massive invasion of Northern Europe associated with genetic admixture and morphological changes occurred in later decades. We suggest that the latter range expansion into far Northern latitudes may be a consequence of the admixture that provided the genetic material for adaptations to new environmental regimes. Hence, global warming could have facilitated the initial admixture of populations and this resulted in genetic lineages with new habitat preferences. PMID:23496675

  20. The effects of Propofol-Thiopental admixture on hemodynamic changes, pain on injection, and hypnotic dose at the time of anesthesia induction: a prospective study

    Directory of Open Access Journals (Sweden)

    Soltani Mohammadi S

    2007-09-01

    Full Text Available   Background: Propofol and Thiopental are intravenous anesthetics having relatively different hemodynamic influences and adverse effects. In addition, there is significant pain on intravenous injection of propofol. This study was performed to examine the effects of Propofol-Thiopental admixture on hemodynamic variables, pain on injection and hypnotic dose at the time of induction of general anesthesia.Methods: One hundred and twenty-five ASA I or II patients scheduled for elective surgery were randomized into four groups for induction of anesthesia in a double-blinded manner. With an original concentration of Propofol of 1% and that of Thiopental of 2.5%, we used these drugs in each group as follows: group P100: Propofol alone; group P75: ¾ Propofol and ¼ thiopental (volume/volume; group P50: ½ Propofol and ½ thiopental; group T100: Thiopental alone (control group. Hemodynamic variables (before and after induction, score of pain on injection and hypnotic doses were recorded and statistically analyzed.Results: Admixture of Thiopental and Propofol reduces the injection pain of Propofol, as admixtures P75 and P50 were significantly less painful on injection than P100. Induction of hypnosis was significantly more rapid in group T100 than in groups P100 and P75. The interaction of Propofol and Thiopental with regard to their hypnotic effect is additive. Therefore a reduction in the dose of one was compensated by proportional increase in the dose of the other drug for a hypnotic effect. After anesthesia induction, systolic and diastolic blood pressures were significantly lower in group P100 than in groups P75, P50 and T100. The heart rate after laryngoscopy and tracheal intubation was significantly lower in group P100 than in groups P50 and T100.Conclusion: Propofol-Thiopental admixture causes minimal pain on injection for intravenous induction of anesthesia with modified hemodynamic effects in comparison with each drug when used separately.

  1. Progress in Lignin-based Concrete Admixtures%含木质素基混凝土外加剂的研究进展

    Institute of Scientific and Technical Information of China (English)

    谌凡琪

    2012-01-01

    综述了木质素在混凝土外加剂中的应用。工业木质素,尤其是木质素磺酸盐,可以充当混凝土减水剂、缓凝剂、引气剂和泵送剂。由于未经改性的工业木质素性能不够理想,为了提高木质素基混凝土添加剂的性能,宜对其进行适当的改性。碱木质素经过氧化、磺化、磺甲基化、接枝共聚等改性后,可以得到具有良好性能的混凝土外加剂。%The applications of lignin derivatives in concrete admixtures are reviewed. Technical lignins, especially lignosulfonates, can serve as concrete water reducers, retarders, air entraining agents and pumping agents. The performance of lignin is not good. Some appropriate modifications are sometimes required in order to improve the performance of the lignin-based concrete admixtures. Lignin-based concrete admixtures with good performaces can be obtained fxom alkali lignin after modifications such as oxidation, sulfonation, sulfomethylation and graft copolymerization.

  2. Brief talk about quality control of various aspects in pharmacy intravenous admixture service%浅谈 PIVAS 工作中各环节质量控制

    Institute of Scientific and Technical Information of China (English)

    石锐

    2015-01-01

    目的:通过分析总结静脉用药调配中心(PIVAS)各工作环节注意事项,为提高工作质量提供参考。方法:分析医嘱审核、摆药、配制等环节,提出针对性的解决措施。结果:加强医嘱审核、科学合理摆药、严密把握配制关等环节可进一步提高各环节质量。结论:通过各工作环节质量控制,为临床提供安全输液的静脉用药。%Objective:To summarize and analyze the points for attention of all work aspects in pharmacy intravenous ad-mixture service(PIVAS),to provide a reference for improve work quality. Methods:By analyzing prescriptions analysis,drug dispensing and admixture,to come up with purposeful solving measures. Results:By means of reinforcing prescription analysis, scientific and reasonable drug dispensing and strict drug admixture and so on,all aspects of work can be further improved. Con-clusion:According to the improvement measure of all work aspects,safe clinical infusion can be provided.

  3. Numerical analysis of the effect of nitrogen and oxygen admixtures on the chemistry of an argon plasma jet operating at atmospheric pressure

    Science.gov (United States)

    Van Gaens, W.; Iseni, S.; Schmidt-Bleker, A.; Weltmann, K.-D.; Reuter, S.; Bogaerts, A.

    2015-03-01

    In this paper we study the cold atmospheric pressure plasma jet, called kinpen, operating in Ar with different admixture fractions up to 1% pure {{N}2}, {{O}2} and {{N}2} + {{O}2}. Moreover, the device is operating with a gas curtain of dry air. The absolute net production rates of the biologically active ozone ({{O}3}) and nitrogen dioxide (N{{O}2}) species are measured in the far effluent by quantum cascade laser absorption spectroscopy in the mid-infrared. Additionally, a zero-dimensional semi-empirical reaction kinetics model is used to calculate the net production rates of these reactive molecules, which are compared to the experimental data. The latter model is applied throughout the entire plasma jet, starting already within the device itself. Very good qualitative and even quantitative agreement between the calculated and measured data is demonstrated. The numerical model thus yields very useful information about the chemical pathways of both the {{O}3} and the N{{O}2} generation. It is shown that the production of these species can be manipulated by up to one order of magnitude by varying the amount of admixture or the admixture type, since this affects the electron kinetics significantly at these low concentration levels.

  4. The effect of the pairing interaction on the energies of isobar analogue resonances in 112-124Sb and isospin admixture in 100-124Sn isotopes

    International Nuclear Information System (INIS)

    In the present study, the effect of the pairing interaction and the isovector correlation between nucleons on the properties of the isobar analogue resonances (IAR) in 112-124Sb isotopes and the isospin admixture in 100-124Sn isotopes is investigated within the framework of the proton-neutron quasi-particle random phase approximation (pnQRPA). The form of the interaction strength parameter is related to the shell-model potential by restoring the isotopic invariance of the nuclear part of the total Hamiltonian. In this respect, the isospin admixtures in the 100-124Sn isotopes are calculated, and the dependence of the differential cross section and the volume integral JF for the Sn(3He,t)Sb reactions at E(3He) =200 MeV occurring by the excitation of IAR on mass number A is examined. Our results show that the calculated value for the isospin mixing in the 100Sn isotope is in good agreement with Colo et al's estimates (4-5%), and the obtained values for the volume integral change within the error range of the value reported by Fujiwara et al (53 ± 5 MeV fm3). Moreover, it is concluded that although the differential cross section of the isobar analogue resonance for the (3He,t) reactions is not sensitive to pairing correlations between nucleons, a considerable effect on the isospin admixtures in N ∼ Z isotopes can be seen with the presence of these correlations

  5. Ultrasound monitoring of the influence of different accelerating admixtures and cement types for shotcrete on setting and hardening behaviour

    International Nuclear Information System (INIS)

    The possible use of ultrasound measurements for monitoring setting and hardening of mortar containing different accelerating admixtures for shotcrete was investigated. The sensitivity to accelerator type (alkaline aluminate or alkali-free) and dosage, and accelerator-cement compatibility were evaluated. Furthermore, a new automatic onset picking algorithm for ultrasound signals was tested. A stepwise increase of the accelerator dosage resulted in increasing values for the ultrasound pulse velocity at early ages. In the accelerated mortar no dormant period could be noticed before the pulse velocity started to increase sharply, indicating a quick change in solid phase connectivity. The alkaline accelerator had a larger effect than the alkali-free accelerator, especially at ages below 90 min. The effect of the alkali-free accelerator was at very early age more pronounced on mortar containing CEM I in comparison with CEM II, while the alkaline accelerator had a larger influence on mortar containing CEM II. The increase of ultrasound energy could be related to the setting phenomenon and the maximum energy was reached when the end of workability was approached. Only the alkaline accelerator caused a significant reduction in compressive strength and this for all the dosages tested

  6. Influence on the physical-mechanical properties of portland-cement mortar, have admixtures of colophony and tannin

    Directory of Open Access Journals (Sweden)

    Fernández Cánovas, M.

    1989-12-01

    Full Text Available The colophony has been used as an admixture in the Portland cement mortar with the intention to observe its influence on the air content, water absorption, adhesive capacity and mechanical properties. The results obtained have shown that, the colophony acts as air entrainment, reduces the permeability and improves the adhesion between the past and aggregates. Likewise, the addition of tannin and montan wax to the colophony has the efect of reducing the formation of foam and improves the impermeability of the mortar.

    Se ha empleado la colofonia como aditivo en el mortero de cemento portland con el fin de observar su influencia sobre el contenido de aire, absorción de agua, capacidad adhesiva y propiedades mecánicas. Los resultados obtenidos han puesto de manifiesto que la colofonia actúa como aireante, aumenta la impermeabilidad y mejora la adherencia de la pasta al árido. Asimismo, la adición de tanino y cera montana a la colofonia tiene el efecto de reducir la formación de espuma y mejorar también la impermeabilidad del mortero.

  7. Effect of Expansive Admixtures on the Shrinkage and Mechanical Properties of High-Performance Fiber-Reinforced Cement Composites

    Directory of Open Access Journals (Sweden)

    Won-Chang Choi

    2013-01-01

    Full Text Available High-performance fiber-reinforced cement composites (HPFRCCs are characterized by strain-hardening and multiple cracking during the inelastic deformation process, but they also develop high shrinkage strain. This study investigates the effects of replacing Portland cement with calcium sulfoaluminate-based expansive admixtures (CSA EXAs to compensate for the shrinkage and associated mechanical behavior of HPFRCCs. Two types of CSA EXA (CSA-K and CSA-J, each with a different chemical composition, are used in this study. Various replacement ratios (0%, 8%, 10%, 12%, and 14% by weight of cement of CSA EXA are considered for the design of HPFRCC mixtures reinforced with 1.5% polyethylene (PE fibers by volume. Mechanical properties, such as shrinkage compensation, compressive strength, flexural strength, and direct tensile strength, of the HPFRCC mixtures are examined. Also, crack width and development are investigated to determine the effects of the EXAs on the performance of the HPFRCC mixtures, and a performance index is used to quantify the performance of mixture. The results indicate that replacements of 10% CSA-K (Type 1 and 8% CSA-J (Type 2 considerably enhance the mechanical properties and reduce shrinkage of HPFRCCs.

  8. Effect of expansive admixtures on the shrinkage and mechanical properties of high-performance fiber-reinforced cement composites.

    Science.gov (United States)

    Choi, Won-Chang; Yun, Hyun-Do

    2013-01-01

    High-performance fiber-reinforced cement composites (HPFRCCs) are characterized by strain-hardening and multiple cracking during the inelastic deformation process, but they also develop high shrinkage strain. This study investigates the effects of replacing Portland cement with calcium sulfoaluminate-based expansive admixtures (CSA EXAs) to compensate for the shrinkage and associated mechanical behavior of HPFRCCs. Two types of CSA EXA (CSA-K and CSA-J), each with a different chemical composition, are used in this study. Various replacement ratios (0%, 8%, 10%, 12%, and 14% by weight of cement) of CSA EXA are considered for the design of HPFRCC mixtures reinforced with 1.5% polyethylene (PE) fibers by volume. Mechanical properties, such as shrinkage compensation, compressive strength, flexural strength, and direct tensile strength, of the HPFRCC mixtures are examined. Also, crack width and development are investigated to determine the effects of the EXAs on the performance of the HPFRCC mixtures, and a performance index is used to quantify the performance of mixture. The results indicate that replacements of 10% CSA-K (Type 1) and 8% CSA-J (Type 2) considerably enhance the mechanical properties and reduce shrinkage of HPFRCCs. PMID:24376382

  9. A multicenter study of biological effects assessment of pharmacy workers occupationally exposed to antineoplastic drugs in Pharmacy Intravenous Admixture Services.

    Science.gov (United States)

    Zhang, Jingjing; Bao, Jianan; Wang, Renying; Geng, Zhou; Chen, Yao; Liu, Xinchun; Xie, Yongzhong; Jiang, Ling; Deng, Yufei; Liu, Gaolin; Xu, Rong; Miao, Liyan

    2016-09-01

    This multi-centered study was designed to evaluate the biological effects of exposure to antineoplastic drugs (ADs) at PIVAS (Pharmacy Intravenous Admixture Service) across ten Chinese hospitals. 8-hydroxy-2-deoxyguanosine (8-OHdG) was used as a biomarker of DNA oxidative damage and lymphocyte apoptosis assays using peripheral lymphocyte cells were used to detect primary DNA damage. The mutagenicity activity was estimated with the Ames fluctuation test. 158 exposed and 143 unexposed workers participated in this study. The urinary 8-OHdG/Cr concentrations of the exposed group was 22.05±17.89ng/mg Cr, which was significantly higher than controls of 17.36±13.50ng/mg Cr (P<0.05). The rate of early lymphocyte apoptosis was slightly increased in exposed group than that of the control group (P=0.087). The mutagenic activity was significantly higher in the exposed group relative to the control group (P<0.05). Moreover, while no statistically significant difference was observed, higher concentrations of 8-OHdG/Cr in urine and an early lymphocyte apoptosis rate were found in exposed group II as compared to exposed group I. In addition, a significant correlation between early lymphocyte apoptosis and exposure time to ADs was also observed (P<0.05). In conclusion, our study identified elevated biomarkers in PIVAS workers exposed to ADs. However whether these findings could lead to increased incidence of genotoxic responses remains to be further investigated. PMID:27179702

  10. Corona discharge experiments in admixtures of N2 and CH4: a laboratory simulation of Titan's atmosphere

    International Nuclear Information System (INIS)

    A positive corona discharge fed by a N2 : CH4 mixture (98 : 2) at atmospheric pressure and ambient temperature has been studied as a laboratory mimic of the chemical processes occurring in the atmosphere of Titan, Saturn's largest moon. In situ measurements of UV and IR transmission spectra within the discharge have shown that the main chemical product is C2H2, produced by dissociation of CH4, with small but significant traces of ethane and HCN, all species that have been detected in Titan's atmosphere. A small amount (0.2%) of CH4 was decomposed after 12 min of treatment requiring an average energy of 2.7 kWh g-1. After 14 min the discharge was terminated due to the formation of a solid yellow deposit on the central wire electrode. Such a deposit is similar to that observed in other discharges and is believed to be an analogue of the aerosol and dust observed in Titan's atmosphere and is composed of chemical species commonly known as 'tholins'. We have also explored the electrical properties of the discharge. The admixture of methane into nitrogen caused an increase in the onset voltage of the discharge and consequently led to a reduction in the measured discharge current.

  11. Unexpected patterns of admixture in German populations of Aedes japonicus japonicus (Diptera: Culicidae) underscore the importance of human intervention.

    Science.gov (United States)

    Zielke, Dorothee E; Werner, Doreen; Schaffner, Francis; Kampen, Helge; Fonseca, Dina M

    2014-01-01

    The mosquito Aedes japonicus japonicus, originally restricted to temperate East Asia, is now widespread in North America and more recently has become established in Europe. To ascertain the putative number of separate introductions to Europe and examine patterns of expansion we analyzed the genetic makeup of Ae. j. japonicus populations from five cemeteries in North Rhine-Westphalia and Rhineland-Palatinate, two western German federal states, as well as of specimens from populations in Belgium, Switzerland, and Austria/Slovenia. To do so, we genotyped individual specimens at seven pre-existing polymorphic microsatellite loci and sequenced part of the nad4 mitochondrial locus. We found evidence of two different genotypic signatures associated with different nad4 mitochondrial haplotypes, indicating at least two genetically differentiated populations of Ae. j. japonicus in Europe (i.e. two distinct genotypes). Belgian, Swiss, and Austrian/Slovenian populations all share the same genotypic signature although they have become differentiated since isolation. Contrary to expectations, the German Ae. j. japonicus are not closely related to those in Belgium which are geographically nearest but are also highly inbred. German populations have a unique genotype but also evidence of mixing between the two genotypes. Also unexpectedly, the populations closest to the center of the German infestation had the highest levels of admixture indicating that separate introductions did not expand and merge but instead their expansion was driven by punctuated human-mediated transport. Critically, the resulting admixed populations have higher genetic diversity and appear invasive as indicated by their increased abundance and recent spread across western Germany. PMID:24992470

  12. Unexpected patterns of admixture in German populations of Aedes japonicus japonicus (Diptera: Culicidae underscore the importance of human intervention.

    Directory of Open Access Journals (Sweden)

    Dorothee E Zielke

    Full Text Available The mosquito Aedes japonicus japonicus, originally restricted to temperate East Asia, is now widespread in North America and more recently has become established in Europe. To ascertain the putative number of separate introductions to Europe and examine patterns of expansion we analyzed the genetic makeup of Ae. j. japonicus populations from five cemeteries in North Rhine-Westphalia and Rhineland-Palatinate, two western German federal states, as well as of specimens from populations in Belgium, Switzerland, and Austria/Slovenia. To do so, we genotyped individual specimens at seven pre-existing polymorphic microsatellite loci and sequenced part of the nad4 mitochondrial locus. We found evidence of two different genotypic signatures associated with different nad4 mitochondrial haplotypes, indicating at least two genetically differentiated populations of Ae. j. japonicus in Europe (i.e. two distinct genotypes. Belgian, Swiss, and Austrian/Slovenian populations all share the same genotypic signature although they have become differentiated since isolation. Contrary to expectations, the German Ae. j. japonicus are not closely related to those in Belgium which are geographically nearest but are also highly inbred. German populations have a unique genotype but also evidence of mixing between the two genotypes. Also unexpectedly, the populations closest to the center of the German infestation had the highest levels of admixture indicating that separate introductions did not expand and merge but instead their expansion was driven by punctuated human-mediated transport. Critically, the resulting admixed populations have higher genetic diversity and appear invasive as indicated by their increased abundance and recent spread across western Germany.

  13. Development of a panel of genome-wide ancestry informative markers to study admixture throughout the Americas.

    Directory of Open Access Journals (Sweden)

    Joshua Mark Galanter

    Full Text Available Most individuals throughout the Americas are admixed descendants of Native American, European, and African ancestors. Complex historical factors have resulted in varying proportions of ancestral contributions between individuals within and among ethnic groups. We developed a panel of 446 ancestry informative markers (AIMs optimized to estimate ancestral proportions in individuals and populations throughout Latin America. We used genome-wide data from 953 individuals from diverse African, European, and Native American populations to select AIMs optimized for each of the three main continental populations that form the basis of modern Latin American populations. We selected markers on the basis of locus-specific branch length to be informative, well distributed throughout the genome, capable of being genotyped on widely available commercial platforms, and applicable throughout the Americas by minimizing within-continent heterogeneity. We then validated the panel in samples from four admixed populations by comparing ancestry estimates based on the AIMs panel to estimates based on genome-wide association study (GWAS data. The panel provided balanced discriminatory power among the three ancestral populations and accurate estimates of individual ancestry proportions (R² > 0.9 for ancestral components with significant between-subject variance. Finally, we genotyped samples from 18 populations from Latin America using the AIMs panel and estimated variability in ancestry within and between these populations. This panel and its reference genotype information will be useful resources to explore population history of admixture in Latin America and to correct for the potential effects of population stratification in admixed samples in the region.

  14. Development of a Panel of Genome-Wide Ancestry Informative Markers to Study Admixture Throughout the Americas

    Science.gov (United States)

    Galanter, Joshua Mark; Fernandez-Lopez, Juan Carlos; Gignoux, Christopher R.; Barnholtz-Sloan, Jill; Fernandez-Rozadilla, Ceres; Via, Marc; Hidalgo-Miranda, Alfredo; Contreras, Alejandra V.; Figueroa, Laura Uribe; Raska, Paola; Jimenez-Sanchez, Gerardo; Silva Zolezzi, Irma; Torres, Maria; Ponte, Clara Ruiz; Ruiz, Yarimar; Salas, Antonio; Nguyen, Elizabeth; Eng, Celeste; Borjas, Lisbeth; Zabala, William; Barreto, Guillermo; Rondón González, Fernando; Ibarra, Adriana; Taboada, Patricia; Porras, Liliana; Moreno, Fabián; Bigham, Abigail; Gutierrez, Gerardo; Brutsaert, Tom; León-Velarde, Fabiola; Moore, Lorna G.; Vargas, Enrique; Cruz, Miguel; Escobedo, Jorge; Rodriguez-Santana, José; Rodriguez-Cintrón, William; Chapela, Rocio; Ford, Jean G.; Bustamante, Carlos; Seminara, Daniela; Shriver, Mark; Ziv, Elad; Gonzalez Burchard, Esteban; Haile, Robert

    2012-01-01

    Most individuals throughout the Americas are admixed descendants of Native American, European, and African ancestors. Complex historical factors have resulted in varying proportions of ancestral contributions between individuals within and among ethnic groups. We developed a panel of 446 ancestry informative markers (AIMs) optimized to estimate ancestral proportions in individuals and populations throughout Latin America. We used genome-wide data from 953 individuals from diverse African, European, and Native American populations to select AIMs optimized for each of the three main continental populations that form the basis of modern Latin American populations. We selected markers on the basis of locus-specific branch length to be informative, well distributed throughout the genome, capable of being genotyped on widely available commercial platforms, and applicable throughout the Americas by minimizing within-continent heterogeneity. We then validated the panel in samples from four admixed populations by comparing ancestry estimates based on the AIMs panel to estimates based on genome-wide association study (GWAS) data. The panel provided balanced discriminatory power among the three ancestral populations and accurate estimates of individual ancestry proportions (R2>0.9 for ancestral components with significant between-subject variance). Finally, we genotyped samples from 18 populations from Latin America using the AIMs panel and estimated variability in ancestry within and between these populations. This panel and its reference genotype information will be useful resources to explore population history of admixture in Latin America and to correct for the potential effects of population stratification in admixed samples in the region. PMID:22412386

  15. Admixture mapping of 15,280 African Americans identifies obesity susceptibility loci on chromosomes 5 and X.

    Directory of Open Access Journals (Sweden)

    Ching-Yu Cheng

    2009-05-01

    Full Text Available The prevalence of obesity (body mass index (BMI > or =30 kg/m(2 is higher in African Americans than in European Americans, even after adjustment for socioeconomic factors, suggesting that genetic factors may explain some of the difference. To identify genetic loci influencing BMI, we carried out a pooled analysis of genome-wide admixture mapping scans in 15,280 African Americans from 14 epidemiologic studies. Samples were genotyped at a median of 1,411 ancestry-informative markers. After adjusting for age, sex, and study, BMI was analyzed both as a dichotomized (top 20% versus bottom 20% and a continuous trait. We found that a higher percentage of European ancestry was significantly correlated with lower BMI (rho = -0.042, P = 1.6x10(-7. In the dichotomized analysis, we detected two loci on chromosome X as associated with increased African ancestry: the first at Xq25 (locus-specific LOD = 5.94; genome-wide score = 3.22; case-control Z = -3.94; and the second at Xq13.1 (locus-specific LOD = 2.22; case-control Z = -4.62. Quantitative analysis identified a third locus at 5q13.3 where higher BMI was highly significantly associated with greater European ancestry (locus-specific LOD = 6.27; genome-wide score = 3.46. Further mapping studies with dense sets of markers will be necessary to identify the alleles in these regions of chromosomes X and 5 that may be associated with variation in BMI.

  16. Chlamydiaceae Genomics Reveals Interspecies Admixture and the Recent Evolution of Chlamydia abortus Infecting Lower Mammalian Species and Humans.

    Science.gov (United States)

    Joseph, Sandeep J; Marti, Hanna; Didelot, Xavier; Castillo-Ramirez, Santiago; Read, Timothy D; Dean, Deborah

    2015-11-01

    Chlamydiaceae are obligate intracellular bacteria that cause a diversity of severe infections among humans and livestock on a global scale. Identification of new species since 1989 and emergence of zoonotic infections, including abortion in women, underscore the need for genome sequencing of multiple strains of each species to advance our knowledge of evolutionary dynamics across Chlamydiaceae. Here, we genome sequenced isolates from avian, lower mammalian and human hosts. Based on core gene phylogeny, five isolates previously classified as Chlamydia abortus were identified as members of Chlamydia psittaci and Chlamydia pecorum. Chlamydia abortus is the most recently emerged species and is a highly monomorphic group that lacks the conserved virulence-associated plasmid. Low-level recombination and evidence for adaptation to the placenta echo evolutionary processes seen in recently emerged, highly virulent niche-restricted pathogens, such as Bacillus anthracis. In contrast, gene flow occurred within C. psittaci and other Chlamydiaceae species. The C. psittaci strain RTH, isolated from a red-tailed hawk (Buteo jamaicensis), is an outlying strain with admixture of C. abortus, C. psittaci, and its own population markers. An average nucleotide identity of less than 94% compared with other Chlamydiaceae species suggests that RTH belongs to a new species intermediary between C. psittaci and C. abortus. Hawks, as scavengers and predators, have extensive opportunities to acquire multiple species in their intestinal tract. This could facilitate transformation and homologous recombination with the potential for new species emergence. Our findings indicate that incubator hosts such as birds-of-prey likely promote Chlamydiaceae evolution resulting in novel pathogenic lineages. PMID:26507799

  17. Parameterization of light scattering for solving the inverse problem of determining the concentrations of the principal light scattering and absorbing admixtures in shelf waters

    Directory of Open Access Journals (Sweden)

    Vadim N. Pelevin

    2001-12-01

    Full Text Available A method for estimating the water backscattering coefficient was put forward on the basis of experimental data of diffuse attenuation coefficient for downwelling irradiance and irradiance reflectance. Calculations were carried out for open sea waters of different types and the spectral dependencies were found ("anomalous" spectra and explained. On this basis, a new model of light backscattering on particles in the sea is proposed. This model may be useful for modelling remote sensing reflectance spectra in order to solve the inverse problems of estimating the concentration of natural admixtures in shelf waters.

  18. African ancestry and its correlation to type 2 diabetes in African Americans: a genetic admixture analysis in three U.S. population cohorts.

    Directory of Open Access Journals (Sweden)

    Ching-Yu Cheng

    Full Text Available The risk of type 2 diabetes is approximately 2-fold higher in African Americans than in European Americans even after adjusting for known environmental risk factors, including socioeconomic status (SES, suggesting that genetic factors may explain some of this population difference in disease risk. However, relatively few genetic studies have examined this hypothesis in a large sample of African Americans with and without diabetes. Therefore, we performed an admixture analysis using 2,189 ancestry-informative markers in 7,021 African Americans (2,373 with type 2 diabetes and 4,648 without from the Atherosclerosis Risk in Communities Study, the Jackson Heart Study, and the Multiethnic Cohort to 1 determine the association of type 2 diabetes and its related quantitative traits with African ancestry controlling for measures of SES and 2 identify genetic loci for type 2 diabetes through a genome-wide admixture mapping scan. The median percentage of African ancestry of diabetic participants was slightly greater than that of non-diabetic participants (study-adjusted difference = 1.6%, P<0.001. The odds ratio for diabetes comparing participants in the highest vs. lowest tertile of African ancestry was 1.33 (95% confidence interval 1.13-1.55, after adjustment for age, sex, study, body mass index (BMI, and SES. Admixture scans identified two potential loci for diabetes at 12p13.31 (LOD = 4.0 and 13q14.3 (Z score = 4.5, P = 6.6 × 10(-6. In conclusion, genetic ancestry has a significant association with type 2 diabetes above and beyond its association with non-genetic risk factors for type 2 diabetes in African Americans, but no single gene with a major effect is sufficient to explain a large portion of the observed population difference in risk of diabetes. There undoubtedly is a complex interplay among specific genetic loci and non-genetic factors, which may both be associated with overall admixture, leading to the observed ethnic differences in diabetes

  19. The matters should pay attention to of polycarboxylic acid admixture in concrete engineering application%聚羧酸外加剂在混凝土工程应用中应注意的问题

    Institute of Scientific and Technical Information of China (English)

    贾钢

    2015-01-01

    结合混凝土外加剂的应用现状,阐述了聚羧酸外加剂的特点及其发展方向,并通过对聚羧酸外加剂在工程应用中常见问题的分析,研究了使用聚羧酸时应注意的具体事项,以供参考。%Combining with the application situation of concrete admixture,this paper elaborated the characteristics and development direction of polycarboxylic acid admixture,and through the analysis on common problems of polycarboxylic acid admixture in engineering application,re-searched the specific matters should be paid attention to using polycarboxylic acid,for reference.

  20. Application of Orthogonal Experiment in Compound Admixture of Freezing Mine Shaft Lining Concrete%正交法在冻结井壁砼复合外加剂试验中的应用

    Institute of Scientific and Technical Information of China (English)

    宗翔; 徐颖; 李寅珺

    2012-01-01

    In order to achieve the setting and hardening of mine shaft lining concrete under the minus temperature in freezing construction and to meet the demands of every performance of concrete, the technique of compounding air entraining admixture and antifreezing admixture and early strength water reducing admixture was applied in this research. Based on the Orthogonal experimental design, several mix proportions of compound admixture for early strength liquid mine shaft lining concrete were developed in the laboratory. The data collected in this research provide reference for the optimum mix proportion of the adulteration quantity of the concrete admixture. The results show that the 2. 1% amount of compound antifreezing admixture achieves favorable effects of liquid,early strength,freezing prevention and antifreezing.%为了使冻结施工井壁混凝土能够在负温条件下凝结与硬化,并满足其各项性能要求,采用引气剂+防冻剂+早强减水剂复合的技术路线,通过正交试验设计复配了适应冻结施工早强流态井壁混凝土的复合外加剂.通过试验分析最终确定各组分掺量之间的最佳配比.复合外加剂的掺量为2.1%,可起到流态、早强、防冻及抗冻的作用.

  1. 糯扎渡水电站混凝土掺合料优选试验%Optimization Tests on Concrete Admixtures in Nuozadu Hydropower Station

    Institute of Scientific and Technical Information of China (English)

    董艳萍; 李锡林; 王清宝; 蒋许章

    2012-01-01

    由于便于就地取材,在实际工程应用中,以矿渣、石灰石粉作为混凝土掺合料较为普遍.针对糯扎渡水电站工程,通过对铁矿渣与石灰石粉掺配的掺合料进行试验研究,优选双掺料品种、掺量及掺配比例,进一步改善了混凝土的性能.%Taking ihe mixture of iron slag powder and lime stone powder as concrete admixture has hern commonly used in recent years in the construction of hydropower projects because of its accessibility. In the construction of Nuozhddu Hydropower Station, the concrete admixture consisted by iron slag powder and lime stone powder is researched by tests, and the varieties, contents and the mixing proportion of double admixlures -powder are also proposed to further improve the performance of concrete..

  2. Eco-genomic analysis of the poleward range expansion of the wasp spider Argiope bruennichi shows rapid adaptation and genomic admixture.

    Science.gov (United States)

    Krehenwinkel, Henrik; Rödder, Dennis; Tautz, Diethard

    2015-12-01

    Poleward range expansions are commonly attributed to global change, but could alternatively be driven by rapid evolutionary adaptation. A well-documented example of a range expansion during the past decades is provided by the European wasp spider Argiope bruennichi. Using ecological niche modeling, thermal tolerance experiments and a genome-wide analysis of gene expression divergence, we show that invasive populations have adapted to novel climatic conditions in the course of their expansion. Their climatic niche shift is mirrored in an increased cold tolerance and a population-specific and functionally differentiated gene expression response. We generated an Argiope reference genome sequence and used population genome resequencing to assess genomic changes associated with the new climatic adaptations. We find clear genetic differentiation and a significant admixture with alleles from East Asian populations in the invasive Northern European populations. Population genetic modeling suggests that at least some of these introgressing alleles have contributed to the new adaptations during the expansion. Our results thus confirm the notion that range expansions are not a simple consequence of climate change, but are accompanied by fast genetic changes and adaptations that may be fuelled through admixture between long separated lineages. PMID:26183328

  3. Chemical composition, effective atomic number and electron density study of trommel sieve waste (TSW), Portland cement, lime, pointing and their admixtures with TSW in different proportions.

    Science.gov (United States)

    Kurudirek, Murat; Aygun, Murat; Erzeneoğlu, Salih Zeki

    2010-06-01

    The trommel sieve waste (TSW) which forms during the boron ore production is considered to be a promising building material with its use as an admixture with Portland cement and is considered to be an alternative radiation shielding material, also. Thus, having knowledge on the chemical composition and radiation interaction properties of TSW as compared to other building materials is of importance. In the present study, chemical compositions of the materials used have been determined using a wavelength dispersive X-ray fluorescence spectrometer (WDXRFS). Also, TSW, some commonly used building materials (Portland cement, lime and pointing) and their admixtures with TSW have been investigated in terms of total mass attenuation coefficients (mu/rho), photon interaction cross sections (sigma(t)), effective atomic numbers (Z(eff)) and effective electron densities (N(e)) by using X-rays at 22.1, 25keV and gamma-rays at 88keV photon energies. Possible conclusions were drawn with respect to the variations in photon energy and chemical composition. PMID:20080413

  4. Spectroscopic study of H2 microwave plasmas with small admixtures of CH4 and B2H6 used for doped diamond deposition

    International Nuclear Information System (INIS)

    Microwave (MW) H2 plasmas with small admixtures of CH4 and/or B2H6 used for doped diamond deposition have been studied by infrared absorption and optical emission spectroscopy (OES) techniques. The experiments were carried out in order to analyze the dependence of the plasma chemistry on several parameters in the MW discharges, such as power, pressure and gas mixture, at relatively high pressures, i.e. up to 300 mbar, and power values, i.e. up to 4 kW. The evolution of the concentrations of five stable molecules, CH4, C2H2, C2H4, C2H6 and B2H6, was monitored in the plasma processes by in situ infrared tunable diode laser absorption spectroscopy. OES was used simultaneously to gather complementary information about the concentration of the boron atom. One target was the determination of the precursors' fragmentation rates and the conversion rates to the molecular reaction products. The analysis of correlations between the power and pressure of the plasma and molecular concentrations, and the differences found with CH4 and B2H6 admixtures were another focus of interest. The degree of dissociation of the carbon containing precursor molecule CH4 varied between 35% and 75%, while the decomposition of diborane, the boron precursor, varied between 85% and 97%. By analyzing the development of the molecular concentrations with changes of gas mixtures, pressure and plasma power values, it was found that (i) C2H2 is the most abundant reaction product in the plasma in the case of methane admixture and (ii) the boron atom concentration depends strongly on the presence of hydrocarbons in the plasma. The fragmentation efficiencies of methane and of diborane (RF(CH4) ≈ (1–2) × 1015 molecules J−1, RF(B2H6) ≈ (0.4–1.4) × 1013 molecules J−1) and the conversion efficiencies to the molecular products (RC(product) ≈ 1013–1015 molecules J−1) have been determined for different gas mixtures and plasma power, and pressure values. The boron atom

  5. Spectroscopic study of H2 microwave plasmas with small admixtures of CH4 and B2H6 used for doped diamond deposition

    Science.gov (United States)

    Hamann, S.; Rond, C.; Pipa, A. V.; Wartel, M.; Lombardi, G.; Gicquel, A.; Röpcke, J.

    2014-08-01

    Microwave (MW) H2 plasmas with small admixtures of CH4 and/or B2H6 used for doped diamond deposition have been studied by infrared absorption and optical emission spectroscopy (OES) techniques. The experiments were carried out in order to analyze the dependence of the plasma chemistry on several parameters in the MW discharges, such as power, pressure and gas mixture, at relatively high pressures, i.e. up to 300 mbar, and power values, i.e. up to 4 kW. The evolution of the concentrations of five stable molecules, CH4, C2H2, C2H4, C2H6 and B2H6, was monitored in the plasma processes by in situ infrared tunable diode laser absorption spectroscopy. OES was used simultaneously to gather complementary information about the concentration of the boron atom. One target was the determination of the precursors' fragmentation rates and the conversion rates to the molecular reaction products. The analysis of correlations between the power and pressure of the plasma and molecular concentrations, and the differences found with CH4 and B2H6 admixtures were another focus of interest. The degree of dissociation of the carbon containing precursor molecule CH4 varied between 35% and 75%, while the decomposition of diborane, the boron precursor, varied between 85% and 97%. By analyzing the development of the molecular concentrations with changes of gas mixtures, pressure and plasma power values, it was found that (i) C2H2 is the most abundant reaction product in the plasma in the case of methane admixture and (ii) the boron atom concentration depends strongly on the presence of hydrocarbons in the plasma. The fragmentation efficiencies of methane and of diborane (RF(CH4) ≈ (1-2) × 1015 molecules J-1, RF(B2H6) ≈ (0.4-1.4) × 1013 molecules J-1) and the conversion efficiencies to the molecular products (RC(product) ≈ 1013-1015 molecules J-1) have been determined for different gas mixtures and plasma power, and pressure values. The boron atom balance, in relation to the

  6. 高性能混凝土外加剂对水泥砂浆力学性能的影响%Mechanical properties research of high-performance concrete admixtures on the cement mortar

    Institute of Scientific and Technical Information of China (English)

    程朝霞; 张自新; 胡志超; 杨健辉

    2011-01-01

    A new type of admixtures on mortar strength was researched with mixed-level orthogonal table.Mixing a few different factors and levels of additives to form a new group of 16 specimens of cement mortar,and testing 3 d and 28 d strength of these prism specimens,then using orthogonal design analysis of variance test methods such as error analysis researched the influence of high-performance concrete admixtures on the cement mortar strength.The results showed that high-performance concrete admixtures are not the most perfect additives.Without reducing water consumption,high performance concrete admixtures with the same quality of cement replacement,the admixtures on the strength of the effect is not significant factors.In the dosage less case,the improvement is not obvious on the strength of concrete,and mixed with excessive can cause retardation.Admixture of polycarboxylate superplasticizer increases the strength.There was an interaction between high-performance concrete admixtures and water reducing agent.%采用混合水平正交表研究了新型外加剂对砂浆强度的影响.通过掺加不同因子及水平数的新型外加剂成型了16组水泥砂浆试件,测试了3 d和28 d龄期的强度,采用正交设计中的方差分析、试验误差等方法分析表明,高性能混凝土外加剂并不是性能最好的外加剂,不减少用水量的情况下,用高性能混凝土外加剂替代同等质量水泥后,外加剂对强度的影响并不是显著因素.掺量较少的情况下,对混凝土强度的提高不明显,掺量过大,会造成缓凝.掺加聚羧酸减水剂提高强度,高性能混凝土外加剂和减水剂之间存在交互作用.

  7. The effect of low-NOx combustion on residual carbon in fly ash and its adsorption capacity for air entrainment admixtures in concrete

    DEFF Research Database (Denmark)

    Pedersen, Kim Hougaard; Jensen, Anker Degn; Dam-Johansen, Kim

    2010-01-01

    Fly ash from pulverized coal combustion contains residual carbon that can adsorb the air-entraining admixtures (AEAs) added to control the air entrainment in concrete. This is a problem that has increased by the implementation of low-NOx combustion technologies. In this work, pulverized fuel has...... by up to a factor of 25. This was due to a lower carbon content in the ash and a lower specific AEA adsorptivity of the carbon. The latter was suggested to be caused by changes in the adsorption properties of the unburned char and a decreased formation of soot, which was found to have a large AEA...... adsorption capacity based on measurements on a carbon black. The NOx formation increased by up to three times with more oxidizing conditions and thus, there was a trade-off between the AEA requirements of the ash and NOx formation. The type of fuel had high impact on the AEA adsorption behavior of the ash...

  8. Y chromosome genetic variation in the Italian peninsula is clinal and supports an admixture model for the Mesolithic-Neolithic encounter.

    Science.gov (United States)

    Capelli, Cristian; Brisighelli, Francesca; Scarnicci, Francesca; Arredi, Barbara; Caglia', Alessandra; Vetrugno, Giuseppe; Tofanelli, Sergio; Onofri, Valerio; Tagliabracci, Adriano; Paoli, Giorgio; Pascali, Vincenzo L

    2007-07-01

    The Italian peninsula, given its geographical location in the middle of the Mediterranean basin, was involved in the process of the peopling of Europe since the very beginning, with first settlements dating to the Upper Paleolithic. Later on, the Neolithic revolution left clear evidence in the archeological record, with findings going back to 7000 B.C. We have investigated the demographic consequences of the agriculture revolution in this area by genotyping Y chromosome markers for almost 700 individuals from 12 different regions. Data analysis showed a non-random distribution of the observed genetic variation, with more than 70% of the Y chromosome diversity distributed along a North-South axis. While the Greek colonisation during classical time appears to have left no significant contribution, the results support a male demic diffusion model, even if population replacement was not complete and the degree of Neolithic admixture with Mesolithic inhabitants was different in different areas of Italy. PMID:17275346

  9. An effect of gamma-neutron irradiation and oxygen admixtures on interaction of hydrogen with austenitic 18Cr-10Ni-Ti steel

    International Nuclear Information System (INIS)

    Experimental data on permeability and diffusion of hydrogen through austenitic 18Cr-10Ni-0.65Ti steel with 0.08 and 0.12 wt.% of carbon have been obtained with special equipment designed and installed at the research reactor IVV-2M. It has been shown that parameters of hydrogen isotope transfer in the steel increased substantially during irradiation by fast neutrons of flux density ffast18 n m-2 per s, fluence F=9.5 x 1024 n m-2 (E>0.1 MeV) and absorbed gamma dose 3.6 W g-1 at temperatures of 573-1073 K. Under these irradiation conditions, even a small oxygen admixture content in hydrogen allowed creation of reliable surface barriers on the steel, which essentially decreased hydrogen permeability. At the same time, the physico-mechanical properties of the steel under study changed. (orig.)

  10. Material and Structural Performance Evaluations of Hwangtoh Admixtures and Recycled PET Fiber-Added Eco-Friendly Concrete for CO2 Emission Reduction

    Directory of Open Access Journals (Sweden)

    Bon-Min Koo

    2014-08-01

    Full Text Available In order to reduce carbon dioxide (CO2 emissions and produce an eco-friendly construction material, a type of concrete that uses a minimal amount of cement, yet still retains equivalent properties to ordinary cement concrete, has been developed and studied all over the world. Hwangtoh, a type of red clay broadly deposited around the world, has traditionally been considered an eco-friendly construction material, with bonus advantages of having health and cost benefits. Presently, Hwangtoh is not commonly used as a modern construction material due to properties such as low strength and high rates of shrinkage cracking. Recent studies, however, have shown that Hwangtoh can be used as a mineral admixture to improve the strength of concrete. In addition, polyethylene terephthalate (PET fibers recycled from PET bottle waste can be used to control shrinkage cracks in Hwangtoh concrete. Therefore, in this study, performance verification is conducted on newly developed Hwangtoh concrete mixed with short recycled PET fibers. The results show that Hwangtoh concrete has compressive strength, elastic modulus, and pH properties that are similar to these features in ordinary cement concrete. The properties of carbonation depth and creep strain of Hwangtoh concrete, however, are larger and smaller, respectively, than in ordinary cement concrete. According to flexural tests, reinforced concrete (RC specimens cast with Hwangtoh admixtures (with and without PET fibers possess similar or better capacities than ordinary RC specimens. The addition of PET fibers significantly improves the structural ductility of RC specimens under normal environmental conditions. However, the implementations of the concrete in aggressive environment must be carefully considered, since a previous study result indicates degradation of its durability performance in aggressive environments, such as seawater [1]. The results of this study validate the possibility of using eco

  11. CO2 capture using fly ash from coal fired power plant and applications of CO2-captured fly ash as a mineral admixture for concrete.

    Science.gov (United States)

    Siriruang, Chaichan; Toochinda, Pisanu; Julnipitawong, Parnthep; Tangtermsirikul, Somnuk

    2016-04-01

    The utilization of fly ash as a solid sorbent material for CO2 capture via surface adsorption and carbonation reaction was evaluated as an economically feasible CO2 reduction technique. The results show that fly ash from a coal fired power plant can capture CO2 up to 304.7 μmol/g fly ash, consisting of 2.9 and 301.8 μmol/g fly ash via adsorption and carbonation, respectively. The CO2 adsorption conditions (temperature, pressure, and moisture) can affect CO2 capture performance of fly ash. The carbonation of CO2 with free CaO in fly ashes was evaluated and the results indicated that the reaction consumed most of free CaO in fly ash. The fly ashes after CO2 capture were further used for application as a mineral admixture for concrete. Properties such as water requirement, compressive strength, autoclave expansion, and carbonation depth of mortar and paste specimens using fly ash before and after CO2 capture were tested and compared with material standards. The results show that the expansion of mortar specimens using fly ash after CO2 capture was greatly reduced due to the reduction of free CaO content in the fly ash compared to the expansion of specimens using fresh fly ash. There were no significant differences in the water requirement and compressive strength of specimens using fly ash, before and after CO2 capture process. The results from this study can lead to an alternative CO2 capture technique with doubtless utilization of fly ash after CO2 capture as a mineral admixture for concrete. PMID:26803257

  12. Analysis of Environmental Impact for Concrete Using LCA by Varying the Recycling Components, the Compressive Strength and the Admixture Material Mixing

    Directory of Open Access Journals (Sweden)

    Taehyoung Kim

    2016-04-01

    Full Text Available Concrete is a type of construction material in which cement, aggregate, and admixture materials are mixed. When cement is produced, large amounts of substances that impact the environment are emitted during limestone extraction and clinker manufacturing. Additionally, the extraction of natural aggregate causes soil erosion and ecosystem destruction. Furthermore, in the process of transporting raw materials such as cement and aggregate to a concrete production company, and producing concrete in a batch plant, substances with an environmental impact are emitted into the air and water system due to energy use. Considering the fact that the process of producing concrete causes various environmental impacts, an assessment of various environmental impact categories is needed. This study used a life cycle assessment (LCA to evaluate the environmental impacts of concrete in terms of its global warming potential, acidification potential, eutrophication potential, ozone depletion potential, photochemical ozone creation potential, and abiotic depletion potential (GWP, AP, EP, ODP, POCP, ADP. The tendency was that the higher the strength of concrete, the higher the GWP, POCP, and ADP indices became, whereas the AP and EP indices became slightly lower. As the admixture mixing ratio of concrete increased, the GWP, AP, ODP, ADP, and POCP decreased, but EP index showed a tendency to increase slightly. Moreover, as the recycled aggregate mixing ratio of concrete increased, the AP, EP, ODP, and ADP decreased, while GWP and POCP increased. The GWP and POCP per unit compressed strength (1 MPa of high strength concrete were found to be about 13% lower than that for its normal strength concrete counterpart. Furthermore, in the case of AP, EP, ODP, and ADP per unit compressed strength (1 MPa, high-strength concrete was found to be about 10%~25% lower than its normal strength counterpart. Among all the environmental impact categories, ordinary cement was found to have

  13. Genetic admixture studies on four in situ evolved, two migrant and twenty-one ethnic populations of Tamil Nadu, south India

    Indian Academy of Sciences (India)

    G. Suhasini; E. Sonaa; S. Shila; C. R. Srikumari; G. Jayaraman; A. Ramesh

    2011-08-01

    We analysed the genetic structure of ∼1000 samples representing 27 ethnic groups settled in Tamil Nadu, south India, derived from two linguistic families (Dravidians and Indo–Europeans) representing four religious groups (Hinduism, Islam, Christianity and Jainism) using 11 mtDNA markers. Out of 27 ethnic groups, four are in situ populations (Anglo-Indian, Labbai Muslim, Nadar Christian and south Indian Jain) and two are migrants (Gypsy and north Indian Jain) from north India to Tamil Nadu, and 21 are native ethnic groups. Six of the markers we used were monomorphic (HaeIII663, HpaI3592, AluI5176, AluI7025, AluI13262, 9-bp deletion) and five markers were polymorphic (DdeI10394, AluI10397, HinfI12308, HincII13259 and HaeIII16517). Haplogroup frequencies, genetic affinities and admixture analysis are based on the genotype data of polymorphic markers observed in these populations. Haplogroup frequencies indicate that various ethnic groups entered Tamil Nadu during different time periods. Genetic affinities and admixture estimates revealed that the ethnic groups possessing advanced knowledge of farming cluster in a branch (C), and could be the late arrived settlers as agriculture, was introduced to this region at about 5 to 3 thousand years ago. In situ ethnic groups appear to have arisen at various times as a result of the prevailing dominant socio-cultural forces. Hierarchical Hindu caste system created many ethnic groups in the history of its existence; some of them became isolated for considerable period of time. Over all, among Tamil ethnic groups, in spite of caste systems’ rigidity, built in flexibility in the system in the form of hypergamy and hypogamy had allowed maternal gene flow between them.

  14. Population genomic analysis uncovers African and European admixture in Drosophila melanogaster populations from the south-eastern United States and Caribbean Islands.

    Science.gov (United States)

    Kao, Joyce Y; Zubair, Asif; Salomon, Matthew P; Nuzhdin, Sergey V; Campo, Daniel

    2015-04-01

    Drosophila melanogaster is postulated to have colonized North America in the past several 100 years in two waves. Flies from Europe colonized the east coast United States while flies from Africa inhabited the Caribbean, which if true, make the south-east US and Caribbean Islands a secondary contact zone for African and European D. melanogaster. This scenario has been proposed based on phenotypes and limited genetic data. In our study, we have sequenced individual whole genomes of flies from populations in the south-east US and Caribbean Islands and examined these populations in conjunction with population sequences from the west coast US, Africa, and Europe. We find that west coast US populations are closely related to the European population, likely reflecting a rapid westward expansion upon first settlements into North America. We also find genomic evidence of African and European admixture in south-east US and Caribbean populations, with a clinal pattern of decreasing proportions of African ancestry with higher latitude. Our genomic analysis of D. melanogaster populations from the south-east US and Caribbean Islands provides more evidence for the Caribbean Islands as the source of previously reported novel African alleles found in other east coast US populations. We also find the border between the south-east US and the Caribbean island to be the admixture hot zone where distinctly African-like Caribbean flies become genomically more similar to European-like south-east US flies. Our findings have important implications for previous studies examining the generation of east coast US clines via selection. PMID:25735402

  15. On exploration for C45 pumping concrete issue with polycarboxylate as admixture%掺聚羧酸盐系外加剂的C45泵送混凝土问题探讨

    Institute of Scientific and Technical Information of China (English)

    李琪; 李晓峰

    2012-01-01

    针对实际施工中掺聚羧酸外加剂的C45泵送混凝土发粘、坍落度损失较快的问题,结合我省现有商品混凝土搅拌站所用原材料、生产工艺,提出了一条有效提高掺聚羧酸外加剂的高标号混凝土和易性的有效途径。%According to some problems of C45 pumping concrete issue with polycarboxylate as admixture, such as stickiness and fast slump loss, the paper points out an effective channel to improve the workability of the high mark concrete with polycarboxylate as admixture by combining with the raw materials and production craft of current commercial concrete in Shanxi.

  16. Thermoelectric behavior of carbon fiber reinforced lightweight concrete with mineral admixtures%炭纤维增强轻质矿粉混凝土的热电行为

    Institute of Scientific and Technical Information of China (English)

    Bahar Demirel; Salih Yazicioglu

    2008-01-01

    Carbon fiber reinforced concrete can be used to sense temperature owing to the Seebeck effect caused by the p-type conductivity of short carbon fibers. Both the temperature sensing ability of the carbon fiber reinforced lightweight concrete and the influence of mineral admixtures on the Seebeck effect were investigated by measuring the thermo electric power of six Portland cement-based concretes with or without carbon fibers or mineral admixtures (fly ash, silica fume). It was found that the carbon fiber reinforced lightweight concretes had a Seebeck effect similar to the carbon fiber reinforced normal concrete, but their Seebeck coefficients were decreased by mineral admixtures. Carbon fiber reinforced lightweight concrete with mineral admixtures can be used as a thermal sensor in buildings.%炭纤维增强混凝土能用来感知温度,其因在于短炭纤维的P-型传导性引起的塞贝克(Seebeck)效应所致.通过测量添加炭纤维或矿质掺和物(飞灰、硅土粉)前后六种波特兰水泥基混凝土的热电功率,研究了炭纤维增强轻质混凝土热敏的能力及其矿质掺合物对Seebeck效应的影响.结果表明: 炭纤维增强轻质混凝土具有类似于炭纤维增强标准混凝土的Seebeck效应,只是Seebeck系数因掺合了矿粉而减低.掺有矿粉的炭纤维增强轻质混凝土可用作建筑物的热传感器.

  17. Application of high performance polycarboxylate concrete admixtures in production of PHC pile%聚羧酸高性能减水剂在PHC管桩生产中的应用

    Institute of Scientific and Technical Information of China (English)

    陈锦光; 王庆军; 黄红建

    2009-01-01

    The QL-PC5 type of high performance polycarboxylate concrete admixture is studied in the production of prestress high-strength concrete pile with their characteristics of performance.%阐述了QL-PC5型聚羧酸高性能减水剂在预应力高强混凝土管桩生产中的应用研究及管桩的性能特点.

  18. 不同内掺材料自密实混凝土的研究现状%Current Status of the Research on Self-compacting Concrete with Different Admixtures

    Institute of Scientific and Technical Information of China (English)

    肖良丽; 刘鸿明; 骆恒

    2015-01-01

    自密实混凝土内掺材料不同不仅影响新拌混凝土的工作性,而且影响硬化混凝土的力学性和耐久性。简要介绍了自密实混凝土的定义及特点,讨论了近年来自密实混凝土内掺材料的发展概况。较详细综述了不同内掺材料自密实混凝土性能研究的最新成果。在此基础上,对内掺材料在自密实混凝土中的研究前景进行了展望。%The different admixtures of self-compacting concrete influence not only the workability of fresh concrete but also the mechanical properties and durability of hardened concrete.The definition and characteristic of self-compac-ting concrete are briefly introduced.The development surveys of self-compacting concrete admixtures in recent years are discussed.The latest results of the property research on self-compacting concrete are summarized.On the basis, the research prospects of admixtures in self-compacting concrete are outlined.

  19. Effect of air entraining admixture on mechanical properties and durability of coarse porous concrete%引气剂对大孔混凝土力学性能及耐久性的影响

    Institute of Scientific and Technical Information of China (English)

    张蔚

    2012-01-01

    The addition of air entraining admixture could improve durability of ordinary concrete effectively, while the effect on coarse porous concrete is not obvious. The article describe the reseach on the effect of air entraining admixture on mechanical properties and durability of coarse porous con- crete. The result shows that the compressive strength and resistance properties to freeze--thaw could be improved with the appropriate amount of air entraining admixture by testing.%引气剂能有效改善普通混凝土的耐久性.但对大孔混凝土性能的影响不明确。本文通过试验,研究不同掺量引气剂对大孔混凝土力学性能及耐久性能的影响。结果表明,适量的引气剂能够增强大孔混凝土的抗压强度和改善抗冻性能。

  20. Experimental and numerical study on the dynamics of a μs helium plasma gun discharge with various amounts of N2 admixture

    Science.gov (United States)

    Bourdon, Anne; Darny, Thibault; Robert, Eric; Pechereau, Francois; Viegas, Pedro; Pouvesle, Jean-Michel

    2015-09-01

    These last years, atmospheric pressure plasma jets formed by pulsed helium discharges ignited in thin dielectric tubes have been extensively studied due to their potential for biomedical applications. So far, most experiments have been dedicated to the study of the plasma plume. For endoscopic treatments, it is also important to better understand and optimize the propagation of discharges in long dielectric tubes as catheters. First we present an experimental and numerical study on the dynamics of a μs helium plasma discharge with N2 admixture in a long dielectric tube. We compare the velocity of the discharge front for various amounts of N2 and different applied voltages and show a good agreement between experiments and simulations. Second, we compare time-resolved measurements and simulations of longitudinal and radial electric fields associated with plasma propagation in the dielectric tube and in the plasma plume. It is interesting to note that measurements obtained with a probe located outside the dielectric tube are in excellent agreement with simulations. This allows to infer from simulations the time evolution of the electric field on the discharge axis which is a key parameter for applications. The authors acknowledge the computational resources of the Mesocentre of Ecole Centrale Paris.

  1. Effect of CO{sub 2}-admixture on the catalytic performance of Ni-Nb-M-O catalysts in oxidative dehydrogenation of ethane to ethylene

    Energy Technology Data Exchange (ETDEWEB)

    Qiao, A.; Kalevaru, V.N.; Martin, A. [Rostock Univ. (Germany). Leibniz-Institut fuer Katalyse e.V.; Hari Kumar, A. Sri; Lingaiah, N.; Prasad, P.S. Sai [Indian Institute of Chemical Technology, Hyderabad (India). Inorganic and Physical Chemistry Div.

    2012-07-01

    In this work, we report the synthesis, characterization and application of Ni-Nb-M-O catalysts with different promoters (M = Cr, Mo, W) for the oxidative dehydrogenation (ODH) of ethane to ethylene. Ni:Nb:M ratio was kept at 1:0.176:0.1 (atomic ratio). The catalysts were calcined at 450 C/5h/air. Catalytic tests were carried out in a fixed bed quartz reactor in the temperature range from 300 to 450 C, with a fixed W/F (1.02 g/cm{sup 3} . s{sup -1}) but with changing mole ratios of C{sub 2}H{sub 6}:O{sub 2}:CO{sub 2}:N{sub 2} (1:0-1.4:1.4-0:2). The product analysis was made off-line using GC equipped with FID. It is evident that the CO{sub 2}-admixture to the reactant feed caused a slight decrease in the conversion of ethane but considerably improved the selectivity of ethylene. Among the three promoters of the same group applied, Cr exhibited superior performance compared to other two. This means increase in d-character of transition metal (i.e. from 3d to 5d) has shown an adverse effect on the conversion of ethane and selectivity of ethylene. (orig.)

  2. The potential of SNP-based PCR-RFLP capillary electrophoresis analysis to authenticate and detect admixtures of Mediterranean olive oils.

    Science.gov (United States)

    Bazakos, Christos; Khanfir, Emna; Aoun, Mariem; Spano, Thodhoraq; Zein, Zeina El; Chalak, Lamis; Riachy, Milad El; Abou-Sleymane, Gretta; Ali, Sihem Ben; Grati Kammoun, Naziha; Kalaitzis, Panagiotis

    2016-07-01

    Authentication and traceability of extra virgin olive oil is a challenging research task due to the complexity of fraudulent practices. In this context, the monovarietal olive oils of Protected Designation of Origin (PDO) and Protected Geographical Indication (PGI) require new tests and cutting edge analytical technologies to detect mislabeling and misleading origin. Toward this direction, DNA-based technologies could serve as a complementary to the analytical techniques assay. Single nucleotide polymorphisms are ideal molecular markers since they require short PCR analytical targets which are a prerequisite for forensic applications in olive oil sector. In the present study, a small number of polymorphic SNPs were used with an SNP-based PCR-RFLP capillary electrophoresis platform to discriminate six out of 13 monovarietal olive oils of Mediterranean origin from three different countries, Greece, Tunisia, and Lebanon. Moreover, the high sensitivity of capillary electrophoresis in combination with the DNA extraction protocol lowered the limit of detection to 10% in an admixture of Tsounati in a Koroneiki olive oil matrix. PMID:26864388

  3. Spatial variability of throughfall in a stand of Scots pine (Pinus sylvestris L.) with deciduous admixture as influenced by canopy cover and stem distance

    Science.gov (United States)

    Kowalska, Anna; Boczoń, Andrzej; Hildebrand, Robert; Polkowska, Żaneta

    2016-07-01

    Vegetation cover affects the amount of precipitation, its chemical composition and its spatial distribution, and this may have implications for the distribution of water, nutrients and contaminants in the subsurface soil layer. The aim of this study was a detailed diagnosis of the spatio-temporal variability in the amount of throughfall (TF) and its chemical components in a 72-year-old pine stand with an admixture of oak and birch. The spatio-temporal variability in the amount of TF water and the concentrations and deposition of the TF components were studied. The components that are exchanged in canopy (H+, K, Mg, Mn, DOC, NH4+) were more variable than the components whose TF deposition is the sum of wet and dry (including gas) deposition and which undergo little exchange in the canopy (Na, Cl, NO3-, SO42-). The spatial distribution was temporally stable, especially during the leafed period. This study also investigated the effect of the selected pine stand characteristics on the spatial distribution of throughfall and its chemical components; the characteristics included leaf area index (LAI), the proportion of the canopy covered by deciduous species and pine crowns, and the distance from the nearest tree trunk. The LAI measured during the leafed and leafless periods had the greatest effect on the spatial distribution of TF deposition. No relationship was found between the spatial distribution of the amount of TF water and (i) the LAI; (ii) the canopy cover of broadleaf species or pines; or (iii) the distance from the trunks.

  4. 掺合料对活性粉末混凝土性能的影响%Effect of Admixture on Mechanical Properties of Reactive Powder Concrete

    Institute of Scientific and Technical Information of China (English)

    陈浩宇; 李俊毅; 王娜; 苏忠纯; 张鹏

    2013-01-01

      活性粉末混凝土具有较高的强度、韧性和耐久性,在一些领域得到很好的应用。但是目前对活性粉末混凝土的研究主要是采用蒸汽养护的方法,蒸汽养护费用高,工艺复杂,不适宜工地使用。文章采用标准养护方法,研究不同掺合料的种类和掺量对活性粉末混凝土力学性能的影响情况。%Reactive powder concrete (RPC) with high strength,toughness and durability,which has been a very good ap-plication in some areas. But the study on reactive powder concrete is mainly the application of steam curing method at pre-sent; steam curing is high cost and complex process, not suitable for the use of the construction site. This paper uses the standard curing method, studies effects on the mechanical properties of reactive powder concrete by different types and dosage admixture.

  5. Kinetic stability of all-in-one parenteral nutrition admixtures in the presence of high dose Ca2+ additive under clinical application circumstances

    Directory of Open Access Journals (Sweden)

    Télessy István G

    2012-05-01

    Full Text Available Abstract Background TPN infusions are usually administered during a treatment period of 10–24 hours per day due to the metabolic capacity of the liver. During this time interval physicochemically stable TPN solution (emulsion is needed for the treatment. The purpose of the present study was to examine how the kinetic stability features of ready-made total parenteral nutrition admixtures containing olive oil and soybean oil will change under the usage-modeling 24-hour application with and without overdose Ca2+. Methods Particle size analysis and zeta potential measurements were carried out to evaluate the possible changes in the kinetic stability of the emulsions. Results Our results indicate that in two of the four mixtures bimodal droplet-size distribution figures were detected and appearance of fat particles over 5 μm can not be disclosed. The tendency for separation of large diameter droplets in the two types of oil-based emulsion systems was different. In case of soybean containing emulsion second peak of droplets appeared in the bottom of the container in contrast to the olive oil containing emulsions where the second peak appeared in the surface layer. Interestingly this phenomenon is independent of calcium-content. Conclusions From therapeutic point the emulsions of the bigger droplets containing upper layer are safer because the potentially dangerous big droplets could remain in the infusion bag after the administration.

  6. Student Award Finalist: Reactive species generated in atmospheric-pressure plasmas with water admixtures for biomedical applications: Absolute measurements and numerical simulations

    Science.gov (United States)

    Schröter, Sandra; Bredin, J.; West, A.; Niemi, K.; Dedrick, J.; de Oliveira, N.; Joyeux, D.; Nahon, L.; Foucher, M.; Booth, J.-P.; Wagenaars, E.; Gans, T.; O'Connell, D.

    2015-09-01

    We investigate the production of atomic oxygen (O), hydroxyl (OH) and atomic hydrogen (H) in an rf atmospheric-pressure plasma operated in helium with water admixtures. These species, and their longer-lived products, are known to influence biological systems. Absolute measurements of species densities are required to develop these plasmas for therapeutics. Accurate determination of radical densities is challenging at elevated pressures in complex gas mixtures due to collisional quenching. We measure radical densities using VUV high-resolution Fourier-transform absorption spectroscopy with synchrotron radiation, UV broadband absorption spectroscopy, and picosecond two-photon absorption laser induced fluorescence (ps-TALIF). These diagnostics are the most suitable techniques allowing direct, absolute and 2-dimensional spatial resolution measurements at atmospheric pressure. Ps-TALIF also enables measurements of the lifetimes of laser-excited states of O and H, providing insight into the chemical kinetics and ambient air diffusion into the plasma jet region. Good agreement has been found between the measurements and a numerical chemical-kinetic simulation. Funding from the UK EPSRC (EP/K018388/1 & EP/H003797/1), the York-Paris Low Temperature Plasma Collaborative Research Centre and financial state aid managed by the laboratory of excellence Plas@Par (ANR-11-IDEX-0004-02).

  7. Corona discharge experiments in admixtures of N{sub 2} and CH{sub 4}: a laboratory simulation of Titan's atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Horvath, G; Skalny, J D; Klas, M; Zahoran, M [Department of Experimental Physics, Comenius University, Mlynska dolina F-2, 842 48 Bratislava (Slovakia); Mason, N J [Department of Physics and Astronomy, The Open University, Walton Hall, MK7 6AA, Milton Keynes (United Kingdom); Vladoiu, R; Manole, M [Ovidius University Constanta, B - dul Mamaia 124, 900527 Constanta (Romania)], E-mail: horeszka@gmail.com

    2009-08-15

    A positive corona discharge fed by a N{sub 2} : CH{sub 4} mixture (98 : 2) at atmospheric pressure and ambient temperature has been studied as a laboratory mimic of the chemical processes occurring in the atmosphere of Titan, Saturn's largest moon. In situ measurements of UV and IR transmission spectra within the discharge have shown that the main chemical product is C{sub 2}H{sub 2}, produced by dissociation of CH{sub 4}, with small but significant traces of ethane and HCN, all species that have been detected in Titan's atmosphere. A small amount (0.2%) of CH{sub 4} was decomposed after 12 min of treatment requiring an average energy of 2.7 kWh g{sup -1}. After 14 min the discharge was terminated due to the formation of a solid yellow deposit on the central wire electrode. Such a deposit is similar to that observed in other discharges and is believed to be an analogue of the aerosol and dust observed in Titan's atmosphere and is composed of chemical species commonly known as 'tholins'. We have also explored the electrical properties of the discharge. The admixture of methane into nitrogen caused an increase in the onset voltage of the discharge and consequently led to a reduction in the measured discharge current.

  8. 静脉药物配置中心退药原因分析%Analysis of the cause of drug withdrawal in Pharmacy intravenous admixture services

    Institute of Scientific and Technical Information of China (English)

    赵丰

    2013-01-01

    目的 分析医院静脉药物配置中心退药现状及原因,促进合理用药.方法 药师通过审查静脉药物配置中心处方,对退药处方进行整理分析.结果 退药原因主要有医生因素、护士因素、工作人员因素、患者因素、药物因素、处方信息因素等.结论 药师通过静脉药物配置中心对退药原因进行分析,降低成本,提高药师的工作效率,减少差错的发生,充分体现了药师的价值.%Objective To analyze the situation and the causes of drug withdrawal in Pharmacy intravenous admixture services(PIVAS) ,to promote the rational drug use in our hospital. Methods The prescriptions of drug withdrawal in PIV AS were collected and analyzed. Results The main reasons for drug withdrawal were the doctor factors, the nurse factors, staff factors, patient factors, drug factors, prescribing information factors. Conclusion Analysis on the reasons of drug withdrawal in PIV AS by pharmacist can reduce the cost, improve working efficiency of pharmacists, reduce the error rate,thus fully embody the value of pharmacist.

  9. 含掺合料混凝土水化产物体积分数计算及其影响因素%Calculation of concrete with mineral admixture hydration products volume fraction and its influential factors

    Institute of Scientific and Technical Information of China (English)

    吴福飞; 董双快; 宫经伟; 陈亮亮; 李东生; 侍克斌

    2016-01-01

    Powers theory proposes calculation method for the pure volume of cement hydration products, which does not apply to calculate the volume of cementitious materials with mineral admixture. The formula of cementitious materials volume was proposed that based on the basic principles of cement and mineral admixture hydration, and the proposed method of reliability was verified by the results of Powers theoretical model and volume fraction of cement hydration products. On this basis, the factor such as water-cement ratio, the ratio of admixture and types was further researched for the volumes of cementitious materials hydration products. Mixture in test were designed 2 water-cement ratio (0.30 and 0.40, respectively), two content (20% and 60%, respectively) of mineral admixture, and 3 kinds of mineral admixture (lithium slag, fly ash and steel slag, respectively), forming paste that was stirred according with the designed ratio in 5 mL centrifuge tube in a blender and curing to 1, 7, 14, 28, 60 and 90 d in curing room (temperature was (20±1)℃, humidity was not less than 95%), and then testing reaction extent of cement and mineral admixture (such as fly ash, steel slag. lithium slag) according with the chemical bound water and HCl dissolution method. The results showed that hydration extent of lithium slag, fly ash and steel slag at 28d decreased by 46.63%, 69.56% and 74.82% (P<0.05) when mineral admixture content varied from 20% to 60% and water-cement ratio was 0.30. Hydration extent of cement at 28 d was increased by 7.25% when water-cement ratio increased from 0.30 to 0.40. When mineral admixture content varied from 20% to 60%, hydration extent of lithium slag, fly ash and steel slag at 28 d increased by 24.14% 18.56%, 17.61% and 8.84%, 12.21%, and 29.37% (P<0.05), respectively. In contrast, the influence of the mineral admixture content was bigger than water-cement ratio for the hydration extent of composite cementitious materials. In different water-cement ratio

  10. Helicobacter pylori genotyping from American indigenous groups shows novel Amerindian vacA and cagA alleles and Asian, African and European admixture.

    Directory of Open Access Journals (Sweden)

    Margarita Camorlinga-Ponce

    Full Text Available It is valuable to extend genotyping studies of Helicobacter pylori to strains from indigenous communities across the world to better define adaption, evolution, and associated diseases. We aimed to genetically characterize both human individuals and their infecting H. pylori from indigenous communities of Mexico, and to compare them with those from other human groups. We studied individuals from three indigenous groups, Tarahumaras from the North, Huichols from the West and Nahuas from the center of Mexico. Volunteers were sampled at their community site, DNA was isolated from white blood cells and mtDNA, Y-chromosome, and STR alleles were studied. H. pylori was cultured from gastric juice, and DNA extracted for genotyping of virulence and housekeeping genes. We found Amerindian mtDNA haplogroups (A, B, C, and D, Y-chromosome DYS19T, and Amerindian STRs alleles frequent in the three groups, confirming Amerindian ancestry in these Mexican groups. Concerning H.pylori cagA phylogenetic analyses, although most isolates were of the Western type, a new Amerindian cluster neither Western nor Asian, was formed by some indigenous Mexican, Colombian, Peruvian and Venezuelan isolates. Similarly, vacA phylogenetic analyses showed the existence of a novel Amerindian type in isolates from Alaska, Mexico and Colombia. With hspA strains from Mexico and other American groups clustered within the three major groups, Asian, African or European. Genotyping of housekeeping genes confirmed that Mexican strains formed a novel Asian-related Amerindian group together with strains from remote Amazon Aborigines. This study shows that Mexican indigenous people with Amerindian markers are colonized with H. pylori showing admixture of Asian, European and African strains in genes known to interact with the gastric mucosa. We present evidence of novel Amerindian cagA and vacA alleles in indigenous groups of North and South America.

  11. Numerical and experimental study of the dynamics of a μs helium plasma gun discharge with various amounts of N2 admixture

    Science.gov (United States)

    Bourdon, Anne; Darny, Thibault; Pechereau, François; Pouvesle, Jean-Michel; Viegas, Pedro; Iséni, Sylvain; Robert, Eric

    2016-06-01

    This paper presents a combined 2D numerical and experimental study of the influence of {{\\text{N}}2} admixture on the dynamics of a He-{{\\text{N}}2} discharge in the 10 cm long dielectric tube of a plasma gun set-up. First, the comparison between experiments and simulations is carried out on the ionization front propagation velocity in the tube. The importance of taking into account a detailed kinetic scheme for the He-{{\\text{N}}2} mixture in the simulations to obtain a good agreement with the experiments is put forward. For the μs driven plasma gun, the two- and three-body Penning reactions occurring in the plasma column behind the ionization front, are shown to play a key role on the discharge dynamics. In the experiments and simulations, the significant influence of the amplitude of the applied voltage on the ionization front propagation velocity is observed. As the amount of {{\\text{N}}2} varies, simulation results show that the ionization front velocity, depends on a complex coupling between the kinetics of the discharge, the photoionization and the 2D structure of the discharge in the tube. Finally, the time evolution of axial and radial components of the electric field measured by an electro-optic probe set outside the tube are compared with simulation results. A good agreement is obtained on both components of the electric field. In the tube, simulations show that the magnitude of the axial electric field on the discharge axis depends weakly on the amount of {{\\text{N}}2} conversely to the magnitude of the off-axis peak electric field. Both, simulations and first measurements in the tube or within the plasma plume show peak electric fields of the order of 45 kV·cm-1.

  12. Male ancestry structure and interethnic admixture in African-descent communities from the Amazon as revealed by Y-chromosome Strs.

    Science.gov (United States)

    Palha, Teresinha de Jesus Brabo Ferreira; Ribeiro-Rodrigues, Elzemar Martins; Ribeiro-dos-Santos, Andrea; Guerreiro, João Farias; de Moura, Luciene Soraya Souza; Santos, Sidney

    2011-03-01

    Some genetic markers on both the Y chromosome and mtDNA are highly polymorphic and population-specific in humans, representing useful tools for reconstructing the past history of populations with poor historical records. Such lack of information is usually true in the case of recent African-descent populations of the New World founded by fugitive slaves throughout the slavery period in the Americas, particularly in Brazil, where those communities are known as quilombos. Aiming to recover male-derived ethnic structure of nine quilombos from the Brazilian Amazon, a total of 300 individuals, belonging to Mazagão Velho (N = 24), Curiaú (N = 48), Mazagão (N = 36), Trombetas (N = 20), Itacoã (N = 22), Saracura (N = 46), Marajó (N = 58), Pitimandeua (N = 26), and Pontal (N = 20), were investigated for nine Y-STRs (DYS393, DYS19, DYS390, DYS389 I, DYS389 II, DYS392, DYS391, DYS385 I/II). From the 169 distinct haplotypes obtained, 120 were singletons. The results suggest the West African coast as the main origin of slaves brought to Brazil (54% of male contribution); the European contribution was high (41%), while the Amerindian's was low (5%). Those results contrast with previous mtDNA data that showed high Amerindian female contribution (46.6%) in African-descent populations. AMOVA suggests that the genetic differentiation among the quilombos is mainly influenced by admixture with European. However, when restricting AMOVA to African-specific haplotypes, low differentiation was detected, suggesting great genetic homogeneity of the African founding populations and/or a later homogenization by intense slave trade inside Brazil. PMID:21302273

  13. The role of SiO2 nanoparticles and ground granulated blast furnace slag admixtures on physical, thermal and mechanical properties of self compacting concrete

    International Nuclear Information System (INIS)

    Research highlights: → Nanoparticles in concrete. → Ground granulated blast furnace slag as concrete's binder. → Mechanical properties of concrete specimens by non-traditional admixtures. - Abstract: In this work, strength assessments and percentage of water absorption of self compacting concrete containing ground granulated blast furnace slag and SiO2 nanoparticles as binder have been investigated. Portland cement was replaced by different amounts of ground granulated blast furnace slag and the properties of concrete specimens were investigated. Although it negatively impacts the physical and mechanical properties of concrete at early ages of curing, ground granulated blast furnace slag was found to improve the physical and mechanical properties of concrete up to 45 wt% at later ages. SiO2 nanoparticles with the average particle size of 15 nm were added partially to concrete with the optimum content of ground granulated blast furnace slag and physical and mechanical properties of the specimens were measured. SiO2 nanoparticle as a partial replacement of cement up to 3.0 wt% could accelerate C-S-H gel formation as a result of increased crystalline Ca(OH)2 amount at the early ages and hence increase strength and improve the resistance to water permeability of concrete specimens. The increased SiO2 nanoparticles' content by more than 3.0 wt%, causes the reduced strength because of the decreased crystalline Ca(OH)2 content required for C-S-H gel formation. Several empirical relationships have been presented to predict flexural and split tensile strength of the specimens by means of the corresponding compressive strength at a certain age of curing. Accelerated peak appearance in conduction calorimetry tests, more weight loss in thermogravimetric analysis and more rapid appearance of the peaks related to hydrated products in X-ray diffraction results, all indicate that SiO2 nanoparticles could improve mechanical and physical properties of the concrete specimens.

  14. 持续质量改进在静脉用药调配中心的应用%Application of Continuous Quality Improvement in Pharmacy Intravenous Admixture Services

    Institute of Scientific and Technical Information of China (English)

    王雅蘋; 苏素红; 朱光辉; 温润姑; 张琼; 张丽萍

    2013-01-01

    In response to the weaknesses in the original management of Pharmacy Intravenous Admixture Services (PIVAS), our hospital has introduced Continuous Quality Control (CQI) as well as manifold reforms and improvements since 2011. The results showed that CQI not only improved PIVAS pharmacists and nurses' risk awareness and admixture capabilities, but also significantly reduced admixture errors. Internal errors made by pharmacists were lowered to 0.01%, a reduction of 36.6%, while external errors by nurses to 0.02‰, a reduction of 28.5%. The conduct ensured patient's safe use of intravenous drugs and promoted patient's satisfaction and healthcare quality.%针对PIVAS静脉药物配置中原有管理方法的不足,我院自2011年以来通过引入持续质量改进管理理念及多方面多环节的改革及完善,结果表明实施持续质量改进后不仅增强了PIVAS药师与配置护士风险意识与安全配置能力,而且静脉药物配置差错发生率明显降低,药师摆药内差为0.01%,降低了36.6%,护士配置外差为0.02‰,降低了28.5%。从而保障了患者静脉用药安全,提高了服务患者满意度和医疗护理质量。

  15. The effect of the pairing interaction on the energies of isobar analogue resonances in {sup 112-124}Sb and isospin admixture in {sup 100-124}Sn isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Babacan, Tahsin [Department of Physics, Celal Bayar University, Manisa (Turkey); Salamov, Djavad [Department of Physics, Anadolu University, Eskisehir (Turkey); Kuecuekbursa, Atalay [Department of Physics, Dumlupinar University, Kuetahya (Turkey); Babacan, Halil [Department of Physics, Celal Bayar University, Manisa (Turkey); Maras, Ismail [Department of Physics, Celal Bayar University, Manisa (Turkey); Aygoer, Hasan A [Department of Physics, Celal Bayar University, Manisa (Turkey); Uenal, Arslan [Department of Physics, Dumlupinar University, Kuetahya (Turkey)

    2004-06-01

    In the present study, the effect of the pairing interaction and the isovector correlation between nucleons on the properties of the isobar analogue resonances (IAR) in {sup 112-124}Sb isotopes and the isospin admixture in {sup 100-124}Sn isotopes is investigated within the framework of the proton-neutron quasi-particle random phase approximation (pnQRPA). The form of the interaction strength parameter is related to the shell-model potential by restoring the isotopic invariance of the nuclear part of the total Hamiltonian. In this respect, the isospin admixtures in the {sup 100-124}Sn isotopes are calculated, and the dependence of the differential cross section and the volume integral J{sub F} for the Sn({sup 3}He,t)Sb reactions at E({sup 3}He) =200 MeV occurring by the excitation of IAR on mass number A is examined. Our results show that the calculated value for the isospin mixing in the {sup 100}Sn isotope is in good agreement with Colo et al's estimates (4-5%), and the obtained values for the volume integral change within the error range of the value reported by Fujiwara et al (53 {+-} 5 MeV fm{sup 3}). Moreover, it is concluded that although the differential cross section of the isobar analogue resonance for the ({sup 3}He,t) reactions is not sensitive to pairing correlations between nucleons, a considerable effect on the isospin admixtures in N {approx} Z isotopes can be seen with the presence of these correlations.

  16. 精细化管理在静脉药物配置中心作业中的应用%Application of Delicacy Management in Pharmacy Intravenous Admixture Services

    Institute of Scientific and Technical Information of China (English)

    王丽华; 范军

    2014-01-01

    Pharmacy intravenous admixture services (PIVAS) aims at improving infusion quality and efficiency. Delicacy management is conducive to improving PIVAS effects by specifying critical PIVAS steps with targeted management.%静脉药物配置中心作业的目的在于提高输液质量,提高输液配制效率,在PIVAS引入精细化管理,将其中关键步骤进行细分,实现针对性的管理,可以有效提升PIVAS作业的效果。

  17. 集束化管理在静脉用药调配中心预防医院感染的应用%Application of Cluster Management in Nosocomial Infection Prevention for Pharmacy Intravenous Admixture Services

    Institute of Scientific and Technical Information of China (English)

    王雅蘋; 苏素红; 戈霓云; 张琼; 朱光辉

    2016-01-01

    Objective To avoid nosocomial infection in the pharmacy intravenous admixture services (PIVAS), our hospital took cluster management strategy on PIVAS, nosocomial infection control department, logistic engineering department and specialized company.Method The combination of self-examination, random check by nosocomial infection control department with equipment maintenance and purification environment by specialized company were adopted to find out the problems, after which cause analysis and quality improvement were conducted.ResultPIVAS infection control measures were made, which helped the inspection and monitoring indicators meet the standard.Conclusion PIVAS nosocomial infection control was improved by cluster management strategy, which ensured patients' intravenous medication safety.

  18. Ancient Admixture in Human History

    OpenAIRE

    Patterson, Nick; Moorjani, Priya; Luo, Yontao; Mallick, Swapan; Rohland, Nadin; Zhan, Yiping; Genschoreck, Teri; Webster, Teresa; Reich, David

    2012-01-01

    Population mixture is an important process in biology. We present a suite of methods for learning about population mixtures, implemented in a software package called ADMIXTOOLS, that support formal tests for whether mixture occurred and make it possible to infer proportions and dates of mixture. We also describe the development of a new single nucleotide polymorphism (SNP) array consisting of 629,433 sites with clearly documented ascertainment that was specifically designed for population gen...

  19. Shrinkage Reducing Admixtures in Construction

    OpenAIRE

    Seguí Femenias, Yurena

    2011-01-01

    Cracking caused by drying or autegenous shrinkage is a real risk for cementitious material and compromise its durability as crack may serve as intgression paths for gases and salts or might permit leaching. Due to special requirements as application thickness, spray application, etc. on the one hand and durability as well as strength on the other hand repair mortars show an increased shrinkage and crack probability, which is highly undesired. In this study it will be investigated wich are the...

  20. Test Research on Compound Polycarboxylic Acid Admixture During Winter Construction%复合型聚羧酸外加剂在冬期施工应用中的试验研究

    Institute of Scientific and Technical Information of China (English)

    杨建国; 王明明; 李忠雨; 娄维萍; 马学伟

    2011-01-01

    Based on the E bid section in one stage of Jinwan Square, reasonable test method is selected during the winter construction of compound polycarboxylic acid admixture.Besides, effects of different concrete mix proportions are studied on the concrete workability, and effects of different maintenance conditions are researched on concrete compressive strength.The optimum mixing amount is chosen by analyzing data to be applied in the engineering.Good economic benefit is obtained.The results show that compound polycarboxylic acid admixture can not only enhance mechanical performance of concrete, but also offer the convenient construction technology.%结合津湾广场一期E标段工程,在聚羧酸外加剂冬期施工中,恰当选取试验方法,考虑不同混凝土配合比对混凝土工作性的影响以及不同养护条件对混凝土抗压强度的影响.经过数据分析,优选了聚羧酸的最佳掺量,并应用于工程中,取得了良好的经济效果.结果表明:复合型聚羧酸外加剂不仅能提高混凝土的力学性能,而且能提供简便易行的施工工艺.

  1. 矿物掺合料混凝土碳化分析的非线性多场耦合模型%Multi-field coupled model for concrete carbonation with mineral admixtures

    Institute of Scientific and Technical Information of China (English)

    余波; 成荻; 杨绿峰

    2014-01-01

    Considering the influences of the type and quantity of the mineral admixtures ,a nonlinear multi-field coupled model for car-bonation analysis of concrete with mineral admixtures was established and verified by combining the rule of diffusion of CO 2 within con-crete with the law of conservation of mass for carbonatable substances.The diffusion coefficient of CO 2,the coefficient of reaction rate be-tween CO2 and carbonatable substances,and the kind and dosage of the carbonatable substances were adopted as the governing parameters in the proposed model.According to the Fick's second law of diffusion and the balance chemical equations ,a nonlinear multi-field coupled model for carbonation analysis of concrete with mineral admixtures was established based on the mechanism of cement hydration ,second hydration of minerals and concrete carbonation first.Then,computation expressions of model parameters,such as the diffusion coefficient of CO2 within concrete,the coefficient of reaction rate between CO2 and carbonatable substances,and the amount of the carbonatable sub-stances,were developed by taking into account the influences of the temperature,relative humidity,water to binder ratio,and mineral ad-mixtures on carbonation.The proposed model was verified by comparing with experimental data and the influences of the temperature ,rel-ative humidity,water to binder ratio and mineral admixtures on carbonation depth were quantificationally investigated based on the distri-bution of CO2,carbonatable substances and the pH value within the concrete.%考虑矿物掺合料种类和掺量的影响,结合混凝土中CO2的扩散规律以及可碳化物质的质量守恒定律,以CO2扩散系数、碳化反应速率系数和混凝土中可碳化物质的量为控制参数,研究建立了矿物掺合料混凝土碳化分析的非线性多场耦合模型,并利用试验数据进行了对比验证。首先基于水泥水化、矿物掺合料二次水化以及混凝土碳化

  2. Formulación de mezclas intratecales para el tratamiento del dolor Compounding of drug admixtures for intrathecal treatment of pain

    Directory of Open Access Journals (Sweden)

    M. P. Ortega-García

    2012-08-01

    intrathecal analgesia are recommended in international consensus, but there are few studies about their stability and safety. The objectives of this review are to evaluate specific considerations for compounded formulations for intrathecal pumps and to review stability studies of drug combinations recommended. Compounding formulations for intrathecal pumps has specific recommendations: avoiding preservatives, antioxidants, and solubility enhancers, using buffers that are compatible with the delivery system, using a pH that is physiologically appropriate and is consistent with the delivery system, normally between 4 and 8, using solutions isotonic with normal CSF, preparing the solution in a manner that does not alter the solubility of the constituents, verifying the chemical and physical stability of the preparation under relevant conditions in accordance with literature and verifying the sterility of the preparation in accordance with the United States Pharmacopeia (Chapter 797 and American Society of Health-System Pharmacist publications. But pharmacist, moreover compounding, play an important role in maintaining quality assurance of intrathecal drug use, validating prescriptions and using standard procedures for ordering and compounding medications, checking dose calculations and monitoring of patients outcomes. Drug combinations for intrathecal analgesia with stability studies are: morphine and ziconotide, morphine and clonidine, ziconotide and bupivacaine, morphine, bupivacaine and clonidine, morphine, ziconotide and clonidine, baclofen and clonidine, ziconotide and baclofen, ziconotide and clonidine, ziconotide and fentanyl. Except for ziconotide combinations, concentration of drugs remains over 90% during 90 days. But ziconotide is very unstable and admixtures with other drugs can accelerate the rate of ziconotide degradation.

  3. The Physicochemical Evaluation and Applicability of Landolphia owariensis latex as a Release Modulating Agent in its Admixture with Carbosil® in Ibuprofen-loaded Self-Emulsifying Oil Formulations

    Directory of Open Access Journals (Sweden)

    N C Obitte

    2009-12-01

    Full Text Available Summary: The need to address the problematic gastric irritation side effects and inconsistent bioavailability of most poorly soluble drugs has drawn the attention of researchers to self emulsifying drug delivery system as one of the possible solutions to these problems. Secondly self emulsifying oil formulations good as they may be could be associated with leakage from their hard gelatin capsules. This further motivated the introduction of gelling agents to address this problem. The objective of this work was to investigate some preliminary properties of Landolphia owariensis latex, including its applicability as a release modulating agent when admixed with Carbosil®, a gelling agent in Ibuprofen-loaded Palm Kernel oil (PKO-based self-emulsifying oil formulations (SEOFs. Purification and precipitation were carried out on the oil and the latex respectively. Some physicochemical properties of the latex were also determined. SEOFs were formulated using varying concentrations of PKO, Tween 80 and Span 85 and thereafter tested for isotropicity. Drug-loaded SEOFs with or without Landolphia owariensis latex (LOL and Carbosil-LOL admixture respectively were evaluated for stability, emulsification time, drug release, aqueous dilution, freeze thaw and drug precipitation tests. Results showed that LOL contained some phytocostituents, had a reasonable adhesive strength, and could retard aqueous permeation. Three out of nine batches of the SEOFs passed the isotropicity test, witnessed no phase separation when emulsified and diluted, and could resist drug precipitation after dilution. LOL did not at all delay drug release from SEOFs unlike LOL-Carbosil admixture. LOL-Carbosil admixture significantly (p<0.05 reduced emulsification time. There was no consistent trend in the dynamic viscosity result. Stability of the SEOFs was maintained at refrigeration temperature of 20C. The above results indicated that LOL, an oil-soluble latex possesses excipient

  4. Mesoscopic perovskite solar cells with an admixture of nanocrystalline TiO2 and Al2O3: role of interconnectivity of TiO2 in charge collection

    Science.gov (United States)

    Cha, Jae-Min; Lee, Jin-Wook; Son, Dae-Yong; Kim, Hui-Seon; Jang, In-Hyuk; Park, Nam-Gyu

    2016-03-01

    Perovskite solar cells with high power conversion efficiency usually employ mesoporous TiO2, however the role of the TiO2 layer has not been clearly resolved. Here we prepared MAPbI3 (MA = CH3NH3) perovskite solar cells with an admixture of nanocrystalline TiO2 and Al2O3 to investigate the role of the mesoporous TiO2 layer. The Al2O3 content was varied from 0% (pure TiO2) to 100% (pure Al2O3) with nominal composition of (1 - x)TiO2 + xAl2O3 (x = 0, 0.25, 0.5, 0.75 and 1). The photocurrent density and fill factor decreased as Al2O3 content increased, whereas the open-circuit voltage was hardly changed. Steady-state photoluminescence (PL) was less quenched as the Al2O3 content increased due to its non-electron-injecting characteristics, where a decrease in PL intensity with increasing TiO2 content was correlated to an increase in photocurrent. Electron injection to TiO2 was also evidenced by time-resolved PL and time-limited photocurrent measurements, where interconnection of TiO2 particles played an important role in charge collection. The slight change in voltage with Al2O3 content was explained by balancing the Fermi position due to a trade-off between charge recombination and the Fermi level. The results observed from the admixture mesoporous layer comprising electron-injecting and electron-non-injecting oxides suggest that electron-injection characteristics play an important role in determining photovoltaic parameters.

  5. 输注静脉营养液滴系数的影响因素分析%Influencing Factors of Drop Coefficient of Total Nutrient Admixture Infusion

    Institute of Scientific and Technical Information of China (English)

    朱刚; 熊想莲; 邱紫; 廖珊; 高兆容; 邝景云; 洪祥乐; 冯结兰; 廖旭嘉

    2013-01-01

      目的探讨输注静脉全营养混合液(total nutrient admixture,TNA)滴系数的主要影响因素,为临床计划输注 TNA提供理论依据。方法模拟输液方法,测定2种不同配方的TNA在3种不同输注管道及2种不同滴注流量下5 mL的滴数各50次,计算出滴系数并比较其差异;测定2种不同配方TNA的表面张力、黏度及密度各20次,比较其差异。结果2种不同配方TNA在同一滴注流量下同一输注管道中滴系数比较差异有统计学意义(P<0.01),不同滴注流量下同一种配方 TNA在同一种输注管道滴系数的比较差异有统计学意义(P<0.01),不同输注管道中同一种配方TNA在同一滴注流量下滴系数的比较差异有统计学意义(P<0.05);2种不同配方TNA的表面张力、黏度及密度差异有统计学意义(P<0.01)。结论临床计划输注TNA时不能按管道包装上标注的滴系数来计算,在相同条件下输注与本研究相同配方的TNA滴系数可按本研究结果计算;输注不同配方 TNA时,可利用本研究结果的规律来推测滴系数的值,精确的方法是在输前实测滴系数的值。%Objective To find out drop coefficient (drops in per mL) of total nutrient admixture (TNA) fluids infusion and its main influencing factors and to provide theoretical basis for planned TNA infusion in the clinical. Methods The drop number in 5 mL TNA with two different formulas in three different infusion tubes and with two different flow rate was measured for 50 times to calculate the average number of drop each milliliter. The influencing factors of drop coefficient were analyzed by measuring the viscosity, density and surface tension of two different formulas of TNA for 20 times. Results It was proved that the difference of drop coefficient between two TNAs with same flow rate and same infusion tube was statistical significant (P<0.01), and the difference of same TNA but with different flow

  6. Study on strength and shrinkage of high performance concrete with compound mineral admixtures%双掺矿物掺合料高性能混凝土的强度与收缩试验研究

    Institute of Scientific and Technical Information of China (English)

    赵素梅; 贡金鑫

    2016-01-01

    对双掺粉煤灰和矿渣的高性能混凝土进行了强度和收缩试验,分析了粉煤灰和矿渣双掺比例(1∶2、2∶3、1∶1)及双掺总量(30%、40%、50%)的影响。研究表明,在双掺比例相同的条件下,随着双掺总量的增加,高性能混凝土强度降低,总收缩和干缩降低,自收缩增加;在双掺总量相同的条件下,随着双掺比例的增加,高性能混凝土早期强度降低,后期强度增加、总收缩降低、自收缩减少和干缩增加。在双掺情况下,单独增加粉煤灰或矿渣的掺量,粉煤灰降低早期强度和总收缩的效果更明显,但矿渣引起自收缩增大的幅度大于粉煤灰引起自收缩减小的幅度;相比于粉煤灰,矿渣降低干缩的效果更明显;矿渣增大自收缩的幅度远小于其降低干缩的幅度。通过回归分析得到了双掺高性能混凝土的收缩计算式。%Experiments were made on the strength and shrinkage properties of high performance concrete with fly ash( FA)and ground granulated blast furnace slag(GGBFS),including the effect of the ratio of FA to GGBFS(1∶2,2∶3,1∶1)and the amount of FA and GG-BFS(30%,40%,50%).The results show that in the case of identical ratio of FA to GGBFS,the strength of the concrete decreases with the increase of the amount of the compound mineral admixtures,while the total shrinkage strain and the drying shrinkage strain reduces and the autogenous shrinkage strain increases. In the case of identical amount of the compound mineral admixtures,the strength of con-crete decreases at early age and increases later with the increase of ratio of FA to GGBFS,while total shrinkage strain and autogenous shrinkage strain decreases and drying shrinkage strain increases. For the compound mineral admixtures,the strength and total shrinkage strain of concrete decrease at early age with the increase of amount of FA or GGBFS. Contrast to GGBFS,the influence of FA is greater

  7. Integration approach of the Couette inverse problem of powder-type self-compacting concrete in a wide-gap concentric cylinder rheometer Part II. Influence of mineral additions and chemical admixtures on the shear thickening flow behaviour of powder type self-compacting concrete

    OpenAIRE

    Heirman, Gert; Hendrickx, Roel; Vandewalle, Lucie; Gemert, Dionys van; Feys, Dimitri; De Schutter, Geert; Desmet, Bram; Vantomme, John

    2009-01-01

    The influence of mineral additions and chemical admixtures on the shear thickening flow behaviour of powder type self-compacting concrete (SCC) is studied by means of a wide-gap concentric cylinder rheometer. The Couette inverse problem is treated by means of the integration method in order to derive the flow curve tau(gamma_dot) from the torque measurements. According to the experimental results, the shear thickening effect is found to be strongly influenced by the addition of the chemica...

  8. 聚羧酸系减水剂在C60高性能混凝土中应用的对比试验研究%Research of polycarboxylates high performance water-reducing admixture in C60 high performance concrete

    Institute of Scientific and Technical Information of China (English)

    高林; 张永恒; 石焱

    2011-01-01

    通过对比试验,探讨了萘系减水剂和聚羧酸系高效减水剂配制的C60高性能混凝土性能.试验结果表明,聚羧酸系减水剂能够很好地满足C60高性能混凝土工作性和强度要求,而萘系减水剂很难达到C60高性能混凝土的要求,聚羧酸系高效减水剂用于C60及以上高强、高性能混凝土,是其应用发展的重要方向.%It discusses the performance of C60 high performance concrete adding naphthalene water reducer and polycarboxylates high performance water-reducing admixture.The result show that polycar1boxylates high performance water-reducing admixture can meet the performance and strength requerements of C60 high performance concrete and naphthalene water reducer can not compare to it.So the major develop direction of polycarhoxylates high performance water-reducing admixture is high-strength and high-performance concrete in C60 and above.

  9. Pharmaceutical Care Practice of Pharmacy Intravenous Admixture Services in Our Hospital%我院静脉药物配置中心的药学服务实践

    Institute of Scientific and Technical Information of China (English)

    许晓东

    2013-01-01

    我院静脉药物配置中心(PIVAS)成立以来,药师借助医院提供的医药信息服务软件、电子审方系统、出仓核对、轨道小车、例会学习等平台开展符合我院实际的药学服务工作。在医嘱审核、药品核对、输液配送等环节为医师、护士、患者提供更加专业的药学服务,保障临床合理用药,提升了自我价值。%Since the establishment of the pharmacy intravenous admixture services ( PIVAS ) , pharmaceutical ser-vices have been carried out by pharmacists in accordance with the actual situation of our hospital by means of the sup-portive platform provided by the hospital such as the medical information service software , electronic prescription sys-tem , warehouse release check and regular meetings , and so on . More professional pharmaceutical services were pro-vided to physicians , nurses and patients in the audit of doctor orders , medicine check and infusion distribution , etc . so as to guarantee the rational drug use and upgrade the self-value of pharmacist .

  10. On the Juvenile Compulsory Education Measures:The Admixture of Compulsory Education Measures and Community Correction%论未成年人强制性教育措施--兼论与社区矫正之契合

    Institute of Scientific and Technical Information of China (English)

    程莹

    2014-01-01

    未成年人强制性教育措施具有灵活、开放和有效的特性,在预防犯罪、维护社会稳定方面发挥着重要作用,但却存在一定程度的滥用。未成年人社区矫正的推行更是加剧了其适用方式的错位与失衡。引入社区矫正,推动未成年人强制性教育措施的去行政化、社会化和多样化。通过两者的衔接与契合,实现对该措施的改造。%Compulsory education measures, with flexible, open and efficient characteristics, play an important role in preventing juvenile crime and maintaining social stability. However, there is a certain degree of abusing compulsory education measures, because they lack the necessary power restriction and statutory authority. The defects of juvenile compulsory education measures become more serious with the implementation of community correction. Introducing the idea of community correction in juvenile compulsory education measures can promote the compulsory education measures to keep the judicature, socialization and diversification. The admixture of compulsory education measures and community correction can improve and perfect juvenile compulsory education measures, and realize the active prevention of minor crime.

  11. 临床药师在静脉药物配置中心批次决策中的作用%Role of clinical pharmacists in batches decision making in pharmacy intravenous admixture services

    Institute of Scientific and Technical Information of China (English)

    秦娜; 魏立伟

    2015-01-01

    Reasonable batch decision-making of pharmacy intravenous admixture services (PIVAS) is a prerequisite for clinical rational drug use in the intravenous infusion. Clinical pharmacists in Luoyang Orthopedics Traumatological Hospital PIVAS draw up intravenous infusion batch rule according to the rational use of drug principle, and take manual intervention in special cases, which make the clinical PIVAS infusion delivery batches more scientific and reasonable, the clinical pharmacists play a decisive role in batches decision making.%静脉药物配置中心合理的批次决策能有效保障临床静脉输液合理用药。河南省洛阳正骨医院临床药师根据合理用药原则,制定静脉输液批次规则,在特殊情况下进行人工干预,使临床输液配送批次更加科学合理。临床药师在批次决策中起到举足轻重的作用。

  12. Experience of Improving the Workflow in Pharmacy Intravenous Admixture Services%改进静脉药物调配中心工作流程的实践和体会

    Institute of Scientific and Technical Information of China (English)

    高文超

    2015-01-01

    目的:持续改进我院静脉药物调配中心的工作流程,提高效率,减少差错。方法:对比我院静脉药物调配中心流程改进前后的不同点,分析其利弊。结果:改进后的流程更符合实际操作,节约成本,提高工作效率,保证合理用药。结论:静脉药物配置中心流程是需要根据实际情况,进行持续质量改进。我院的流程改进是卓有成效的。%OBJECTIVE:Improving the Workflow in Pharmacy Intravenous Admixture Services,to improve efficiency and reduce errors.METHODS:Comparison of process improvement,analyse its advantages and disadvantages.RESULTS:The improved process is more consistent with the actual operation, save cost,improve work efficiency,ensure the rational use of drugs.CONCLUSIONS:PIVAS according to the practical situation,continuous quality improve-ment.Our process improvement is very fruitful.

  13. Establishment of pharmacy intravenous admixture service in our hospital and its signification%我院静脉药物配置中心的开展与意义

    Institute of Scientific and Technical Information of China (English)

    林良沫

    2012-01-01

    By introducing the establishment, personnel, processes and other aspects about pharmacy intravenous admixture service (PIVAS) and analyzing the deficiencies of PIVAS which needed to be improved, this article discusses the significance of PIVAS in our hospital. PIVAS can promote the development of clinic pharmacy, ensure ' the safety of drugs use and improve the nursing quality, which is sure to be of great importance to the clinical pharmacy practice in our hospital.%通过介绍我院PIVAS的设施、人员和工作流程等情况,探讨开展PIVAS的意义并在工作实践中分析PIVAS存在的不足之处.PIVAS能有效促进医院临床药学的发展,有利于保障用药安全、提高护理质量等.PIVAS的开展对我院临床药学实践具有重要意义.

  14. Experience of Improving the Workflow in Pharmacy Intravenous Admixture Services%改进静脉药物调配中心工作流程的实践和体会

    Institute of Scientific and Technical Information of China (English)

    高文超

    2015-01-01

    Objective Improving the Workflow in Pharmacy Intravenous Admixture Services,to improve ef iciency and reduce er ors. Methods Comparison of process improvement, analyse its advantages and disadvantages. Results The improved process is more consistent with the actual operation, save cost, improve work ef iciency, ensure the rational use of drugs. Conclusion PIVAS according to the practical situation, continuous quality improvement. Our process improvement is very fruitful.%目的:持续改进我院静脉药物调配中心的工作流程,提高效率,减少差错。方法对比我院静脉药物调配中心流程改进前后的不同点,分析其利弊。结果改进后的流程更符合实际操作,节<成本,提高工作效率,保证合理用药。结论静脉药物配置中心流程是需要根据实际情况,进行持续质量改进。我院的流程改进是卓有成效的。

  15. Experimental research on pervious concrete mixed with low - quality active mineral admixture%低品质活性矿物掺合料透水混凝土试验研究

    Institute of Scientific and Technical Information of China (English)

    高润东; 许清风; 李向民; 贡春成

    2015-01-01

    Performance tests were conducted on pervious concrete mixed with low - quality active mineral admixture,including adding single low - quality silica fume,adding single low - quality fly ash,and adding both low - quality silica fume and low - quality fly ash. Macro - observations involve compressive strength,flexural strength,porosity and permeability coefficient.Micro - observations involve microstructure of cemented layer by SEM and chemical composition of cemented layer by EDS.Results indicate mixed with a certain a-mount of low - quality active mineral admixture in place of cement in ordinary pervious concrete is feasible. Adding single low - quality silica fume with mass fraction of about 6%works best,followed by adding single low - quality fly ash with mass fraction of about 15%. Whether adding single low - quality silica fume or adding single low - quality fly ash,the strength class of concrete is about C15,the porosity is not less than 20%,and the permeability coefficient is not less than 20 × 10 - 2 cm?s,which meet with application conditions of ordinary light traffic pavements.%通过试验研究了低品质活性矿物掺合料透水混凝土的基本性能,包括单掺低品质硅灰、单掺低品质粉煤灰、双掺低品质硅灰和粉煤灰。宏观上测试了抗压强度、抗折强度、孔隙率和透水系数;微观上用 SEM 观测了胶结层的微观结构、用 EDS 观测了胶结层的化学组成。试验结果表明:在普通透水混凝土中掺入一定量的低品质活性矿物掺合料替代部分水泥是可行的;单掺低品质硅灰效果最佳、掺量可在6%左右,单掺低品质粉煤灰次之、掺量可在15%左右;单掺低品质硅灰透水混凝土和单掺低品质粉煤灰透水混凝土强度等级为 C15左右,孔隙率均不低于20%,透水系数均不低于20×10-2 cm?s,可以满足一般轻交通路面的应用条件。

  16. Influence of mineral admixture double mixing on the cement base material rheological properties%矿物掺合料复掺对水泥基材料流变性能的影响

    Institute of Scientific and Technical Information of China (English)

    马保国; 付浩兵; 王慧贤; 王迎斌; 田振; 卢斯文

    2013-01-01

    The Marsh cone method,H tube method,micro slumps method and rheometer method are used to study the influence of double mixing of fly ash and mineral powder in polycarboxylic acid system on liquidity and rheological properties of cement slurry.Test results show that when the mineral admixture total substitution increased from 20% to 40%,flow rate was increasing; while in total dosage fixed condition,with the fly ash content increased,the rheology was reducing;Rheological test results show that,when the total substitution is 30%,the slurry exhibits a linear Newtonian fluid properties,and when the replace content is 20% and 40%,the slurry exhibits the characteristics of nonlinear pseudoplastic fluid.%采用Marsh筒法、H管法、微型坍落度法与流变仪法研究了在聚羧酸体系中复掺粉煤灰和矿粉2种矿物掺合料对水泥浆体流动性和流变性能的影响.试验结果表明:矿物掺合料的总取代量从20%增加到40%时,流动速度呈增大趋势;而在总掺量固定的条件下,随着粉煤灰掺量增加,流变性呈降低的趋势;流变试验结果表明,当总取代量为30%时,浆体表现出线性的牛顿流体特性,而总取代量为20%和40%时,浆体表现出非线性假塑性流体的特征.

  17. The SSR-based molecular profile of 1005 grapevine (Vitis vinifera L.) accessions uncovers new synonymy and parentages, and reveals a large admixture amongst varieties of different geographic origin.

    Science.gov (United States)

    Cipriani, Guido; Spadotto, Alessandro; Jurman, Irena; Di Gaspero, Gabriele; Crespan, Manna; Meneghetti, Stefano; Frare, Enrica; Vignani, Rita; Cresti, Mauro; Morgante, Michele; Pezzotti, Mario; Pe, Enrico; Policriti, Alberto; Testolin, Raffaele

    2010-11-01

    A collection of 1005 grapevine accessions was genotyped at 34 microsatellite loci (SSR) with the aim of analysing genetic diversity and exploring parentages. The comparison of molecular profiles revealed 200 groups of synonymy. The removal of perfect synonyms reduced the database to 745 unique genotypes, on which population genetic parameters were calculated. The analysis of kinship uncovered 74 complete pedigrees, with both parents identified. Many of these parentages were not previously known and are of considerable historical interest, e.g. Chenin blanc (Sauvignon × Traminer rot), Covè (Harslevelu selfed), Incrocio Manzoni 2-14 and 2-15 (Cabernet franc × Prosecco), Lagrein (Schiava gentile × Teroldego), Malvasia nera of Bolzano (Perera × Schiava gentile), Manzoni moscato (Raboso veronese × Moscato d'Amburgo), Moscato violetto (Moscato bianco × Duraguzza), Muscat of Alexandria (Muscat blanc à petit grain × Axina de tres bias) and others. Statistical robustness of unexpected pedigrees was reinforced with the analysis of an additional 7-30 SSRs. Grouping the accessions by profile resulted in a weak correlation with their geographical origin and/or current area of cultivation, revealing a large admixture of local varieties with those most widely cultivated, as a result of ancient commerce and population flow. The SSRs with tri- to penta-nucleotide repeats adopted for the present study showed a great capacity for discriminating amongst accessions, with probabilities of identity by chance as low as 1.45 × 10(-27) and 9.35 × 10(-12) for unrelated and full sib individuals, respectively. A database of allele frequencies and SSR profiles of 32 reference cultivars are provided. PMID:20689905

  18. 掺加粉煤灰和矿粉对嵌缝加固胶泥性能的试验研究%Experimental research on admixture of fly ash and mineral powder on the properties of reinforced cement sealing

    Institute of Scientific and Technical Information of China (English)

    胡向阳; 何忠茂; 何廷树

    2014-01-01

    In order to study the fly ash and mineral powder on the properties of cement sealing,Experimental research on different age, different content of fly ash and mineral powder to cement caulking compressive strength.And use the SEM ,mercury injection apparatus to analyze its microcosmic mechanism.Experiment shows that the fly ash and mineral powder after sealing isometric substitute cement in the cement caulking, the flexural compressive strength with the increase of the dosage of admixture showed a trend of decline.Double mixing fly ash mineral powder group of microscopic test results show that the most probable aperture smaller than single mixing fly ash mineral group,and double mixing group later hydration products is rich,is conducive to the growth of the late strength.%为了研究粉煤灰、矿粉对嵌缝胶泥性能的影响,对粉煤灰、矿粉不同龄期不同掺量的嵌缝胶泥进行抗折、抗压强度试验。并使用SEM、压汞仪分析其微观机理。试验表明:粉煤灰、矿粉在等量取代嵌缝胶泥中的水泥之后,其抗折抗压强度随掺合料掺量的增加呈现下降趋势。双掺粉煤灰矿粉组的微观测试结果显示其最可几孔径小于单掺粉煤灰矿粉组,且双掺组后期的水化产物丰富,有利于后期强度的增长。

  19. Management and operation effects of the outpatient and emergency department pharmacy intravenous admixture services%我院门急诊静脉药物配置中心的管理及运行效果

    Institute of Scientific and Technical Information of China (English)

    苏涣新; 黄灿炘

    2012-01-01

    Objective To explore the operation mechanism and effects of an outpatient and emergency department pharmacy intravenous admixture services ( PIVAS). Methods Many measures were taken,such as defining personal responsibilities,formulating reasonable management models,working processes,transfusion processes for outpatients and emergency patients, and quality control standards, implementing on - the -job training for nursing staff and layered quality control, and so on. Results It ensured the safety of clinical intravenous medication,reduced the occurrence of unreasonable drug use,drug wasting,and adverse drug events. Conclusion The PIVAS in outpatient and emergency department can improve the safety of clinical intravenous medication and increase patient satisfaction.%目的 探讨门急诊静脉药物配制中心管理机制及运行效果.方法 明确人员职责与排班,制订合理的管理模式、工作流程、门诊患者输液流程、急诊患者输液流程及质量管理规范,并对护理人员进行岗位培训,制订管理规范和工作流程,进行分层质量控制.结果 管理制度的运行保证了临床静脉用药安全,减少了不合理用药、药品浪费以及用药不良事件的发生.结论 门诊静脉药物配置中心在提高患者静脉用药安全和提高患者满意度方面发挥了积极的作用.

  20. The influence of sulfuric environments on concretes elaborated with sulfate resistant cements and mineral admixtures. Part 2: Concrete exposed to Magnesium Sulfate (MgSO4) = Estudio de la influencia de los medios con presencia de sulfatos en hormigones con cementos sulforresistentes y adiciones minerales. Parte 2.Hormigones expuestos a sulfato magnésico (MgSO4)

    OpenAIRE

    Bernal Camacho, Jesús Manuel; Mahmoud Abdelkader, Safwat; Reyes Pozo, Encarnación; Monteagudo Viera, Silvia M.

    2013-01-01

    The present work studies the resistant of the concrete against magnesium sulfate (MgSO4) and compare the results with values obtained previously of the same concretes exposed to sodium sulfate (Na2SO4). Thus, it is possible analyze the influence of the cation type. To that end, four different concrete mixes were made with sulfur resistant cement and mineral admixtures (silica fume, fly ash and blast furnace slag). The concretes were submerged for different period in magnesium sulfate (MgSO4)....

  1. EFFECT OF SHRINKAGE REDUING ADMIXTURE ON HYDRATION AND PORE STRUCTURE OF CEMENT-BASED MATERIALS%减缩剂对水泥基材料水化和孔结构的影响

    Institute of Scientific and Technical Information of China (English)

    张志宾; 徐玲玲; 唐明述

    2009-01-01

    The effect of shrinkage reducing admixture (SPA) on hydration process and pore structure of cement-based materials was studied. The hydration heat, chemically combined water and Ca(OH)2 content of cement paste and pore structure of mortar were measured by isothermal calorimeter, gravimetric method, X-ray diffraction and mercury intrusion porosimetry. The results indicate that the SPA has a slight retarding effect on hydration of cement, and the hydration of paste with and without the SPA tended to be the same with increasing the curing time. The appearance time of exothermic peak can be delayed, and the peak value as well as the hydration heat of cement can be lowered by adding the SPA. The chemically combined water of the SPA paste is less than that of the controlled sample. A difference of hydration between the controlled paste and the SPA paste is shortened with hydration age. The Ca(OH)2 content of the SPA paste is less than that of the controlled paste at 3 d, but they are similar at 28 d. Furthermore, the pore volume can be reduced and the innocuous pores can be increased by the SPA used. In addition, the resultant formation of the SRA in pore solution of cement-based materials was supposed.%通过对水泥净浆水化放热量、Ca(OH)2的含量和化学结合水量及水泥砂浆的孔结构的测定,研究减缩剂对水泥基材料水化和孔结构的影响.结果表明:减缩剂会延缓水泥的水化,且随着龄期的发展,延缓作用渐弱.具体表现为减缩剂会降低水泥水化放热的峰值,延迟峰值出现的时间,减小水化放热量;减缩剂能够减小水泥净浆的化学结合水量;龄期为3d时,掺减缩剂的净浆中Ca(OH)2的含量明显低于空白样的,28d时与空白样的相当;减缩剂能够减小水泥砂浆中多害孔和有害孔的孔体积,增加无害孔的孔体积.另外还对减缩剂在水泥基材料中存在的形态提出设想.

  2. Analysis of Practice and Results of Quality Control Circle in Pharmacy Intravenous Admixture Services%品管圈在静脉用药调配中心的实践与结果分析

    Institute of Scientific and Technical Information of China (English)

    薛进; 罗建华; 张先明

    2013-01-01

    Objective:Through carrying out quality control circle (QCC) in pharmacy intravenous admixture services (PIVAS),to reduce medicine configuration errors,ensure patients' medication safety and improve the level of pharmaceutical affairs management in hospital.Methods:Introduce concept of quality management,use a variety of statistical methods,and solve problems in practice work by seven QC gimmick.Results:Configuration errors in the process of PIVAS fell by an average of 34.00 per month to an average of 17.17 per month after implementation of QCC.Conclusions:Operating QCC on the management of medicine configuration and quality in PIVAS,can greatly exert the team cooperation ability of whole department,reduce the medicine configuration errors,improve the quality of the medicine,and reduce the risk in the process of practice.%目的:通过在静脉用药调配中心(PIVAS)推行品管圈活动,减少药物调配差错,保障患者用药安全,提高医院药事管理水平.方法:引入品质管理概念,运用多种统计方法,按照品管七大手法来解决实际工作中的问题.结果:PIVAS药物调配过程的差错由改善前的平均每月34.00例降低至改善后的平均每月17.17例.结论:将品管圈的改善方法运用于PIVAS的药物调配质量管理中,可以极大发挥整个科室团队协作能力,减少药物调配差错,提高药物调配质量,降低工作过程中的风险.

  3. Admixture and Drift in Oscillating Fluid Flows

    CERN Document Server

    Vladimirov, V A

    2010-01-01

    The motions of a passive scalar $\\hat{a}$ in a general high-frequency oscillating flow are studied. Our aim is threefold: (i) to obtain different classes of general solutions; (ii) to identify, classify, and develop related asymptotic procedures; and (iii) to study the notion of drift motion and the limits of its applicability. The used mathematical approach combines a version of the two-timing method, the Eulerian averaging procedure, and several novel elements. Our main results are: (i) the scaling procedure produces two independent dimensionless scaling parameters: inverse frequency $1/\\omega$ and displacement amplitude $\\delta$; (ii) we propose the \\emph{inspection procedure} that allows to find the natural functional forms of asymptotic solutions for $1/\\omega\\to 0, \\delta\\to 0$ and leads to the key notions of \\emph{critical, subcritical, and supercritical asymptotic families} of solutions; (iii) we solve the asymptotic problems for an arbitrary given oscillating flow and any initial data for $\\hat{a}$; ...

  4. Tests on concrete containing cork powder admixtures

    Directory of Open Access Journals (Sweden)

    Guerra, I.

    2007-06-01

    Full Text Available The present study aimed to determine the physical and mechanical properties of laboratory concrete made with different proportions of cork powder. While the resulting material lacked the mechanical strength characteristic of concrete, its properties may prove to be apt for certain hardscaping and agricultural uses, such as in the manufacture of pavement for playgrounds and parks, or certain kinds of structures used in livestock raising. These findings need to be analyzed and verified.Este trabajo de investigación tiene por objeto conocer algunas propiedades físicas y mecánicas de un hormigón elaborado en laboratorio, adicionándole diversas proporciones de polvo de corcho. Las propiedades del material resultante, si bien carecen de la resistencia mecánica que caracteriza al hormigón, parecen interesantes para su uso en ciertas aplicaciones de la ingeniería agronómica tales como en la fabricación de piezas para solados de parques infantiles y jardines, o en los cubículos de ciertas construcciones ganaderas, extremos que es preciso analizar y comprobar.

  5. 掺黏度改性剂与减水剂水泥浆的zeta电位研究%Study on Zeta Potential of Cement Pastes with Viscosity Modifying Admixtures and Superplasticizers

    Institute of Scientific and Technical Information of China (English)

    钟世云; 李晋梅; 韩冬冬; 倪坤

    2012-01-01

    采用zeta(ξ)电位仪研究了黏度改性剂(VMA)、减水剂单掺以及VMA与减水剂复掺对水泥浆ξ电位的影响.结果表明:由于水泥粒子吸附VMA或减水剂分子,因此单掺VMA或减水剂水泥浆ξ电位降低.VMA与聚羧酸系减水剂(PC)同掺水泥浆表现出来的主要是水泥粒子吸附PC分子后的ξ电位特性;VMA与萘系减水剂(NF)同掺水泥浆ξ电位绝对值比单掺NF水泥浆低.无论是滴加PC到掺VMA水泥浆中还是滴加VMA到掺PC水泥浆中,水泥浆ξ电位都有所提高;VMA的加入使得掺NF水泥浆的ξ电位升高,但仍低于两者同掺水泥浆的ξ电位;在掺VMA水泥浆中,当NF滴加量达到一定值时,水泥浆ξ电位绝对值甚至高于两者同掺水泥浆ξ电位绝对值.%The influence of viscosity modifying admixturesC VMA) and superplasticizers and mixing of these two agents on zeta(ζ) potential of cement pastes(fresh) were analyzed using the ZetaProbe instrument. The experimental results show that since cement grains adsorb VMA or superplasticizer molecules, the ζ potential of cement pastes with VMA or superplasticizer decreases. The ζ potential of cement pastes with both VMA and polycarboxylic superplasticizer (PC) shows that cement grains primarily adsorb PC molecules, whereas the absolute value of ζ potential of cement pastes with both VMA and naphthalene formaldehyde condensate superplasticizer(NF) is lower than that with only NF. To add PC into cement pastes with VMA or to add VMA into cement pastes with PC will result in the ζ potential increase. The ζ potential of cement pastes with NF increases from —8 mV to —3 mV as VMA is added in. However, it is still lower than that with both VMA and NF. The f potential of cement pastes with VMA decreases as NF is added in, and the ζ potential absolute value is higher than that with both VMA and NF when the use level of NF increases to a certain value.

  6. INFLUENCE OF GROUND MINERAL ADMIXTURES ON PORE STRUCTURE OF HARDENED CEMENT PASTE AND STRENGTH OF CEMENT MORTAR%磨细矿物掺合料对水泥硬化浆体孔结构及砂浆强度的影响

    Institute of Scientific and Technical Information of China (English)

    李永鑫; 陈益民

    2006-01-01

    采用压汞法研究了钢渣、矿渣、粉煤灰单掺或复掺对水泥硬化浆体孔结构的影响.同时还研究了掺合料单掺或复掺对水泥砂浆抗压强度的影响.结果表明:掺合料单掺或复掺对早期水泥硬化浆体的孔结构有一定的劣化作用;水化后期,矿渣与钢渣均明显降低了水泥硬化浆体的孔隙率,矿渣与粉煤灰均明显降低了水泥硬化浆体的中值孔径并改善了水泥石的孔径分布,掺合料复掺对改善水泥硬化浆体的孔结构有积极作用,尤其是掺合料三元复合可取得最佳的效果.3种掺合料降低水泥硬化浆体孔隙率能力的大小顺序为:矿渣>钢渣>粉煤灰.3种掺合料降低水泥硬化浆体孔径并改善孔径分布能力的大小顺序为:矿渣>粉煤灰>钢渣.掺合料降低了水泥砂浆早期的抗压强度,却增加了水泥砂浆90 d的抗压强度.掺合料的活性大小顺序为:矿渣>钢渣>粉煤灰.%The influence of singly and compositely adding steel slag, blast furnace slag and fly ash on the pore structure of handened cement paste was studied using mercury intrusion porosimetry (MIP). Furthermore, their influence on the compressive strength of cement mortar was also investigated. The results show that the pore structure of cement paste become worse at early ages by singly or compositely adding any of the mineral admixtures. At later ages, adding either blast furnace slag or steel slag remarkably reduces the porosity of cement paste, while either blast furnace slag or fly ash remarkably reduces median pore diameter and improves pore size distribution. The most reduction in the porosity of cement paste is observed for the cement with blast furnace slag, while the cement with steel slag less, and the cement with fly ash the least. The biggest improvement on pore structure is observed for the cement with blast furnace slag, while the cement with fly ash smaller, and the cement with steel slag the smallest. Pore structure

  7. 基于六西格玛理论优化我院静脉用药调配中心的工作流程%Optimization of the workflow of pharmacy intravenous admixture service center based on the six Sigma theory

    Institute of Scientific and Technical Information of China (English)

    郝春凤; 杨跃辉; 菅凌燕

    2012-01-01

    Objective Based on the six Sigma theory, to optimize the workflow of pharmacy intravenous admixture service center and improve the work efficiency. Method According to the five-step method of six Sigma theory ( DMAIC ) , we determine the non-effective factors and implement the improved measures. Result During the whole processes, we finally determined and revised three kinds of no-effective factors, including how to arrange personnel, distribute the different work and adjust the hospital electronic information system. Conclusion The six Sigma theory significantly improves the work efficiency of pharmacy intravenous admixture service center, and the whole workflow is tended to be standardized and normalized.%目的 基于六西格玛理论,优化静脉用药调配中心工作流程,提高工作效率.方法 依据六西格玛五步法(DMAIC),界定并测量非增效因素,制定有针对性的改进措施并严格执行.结果 在整个优化工作流程过程中,共界定并改进了3种主要的非增效因素,包括人员的安排、工作的分配、医院电子信息化系统的设置.结论 采用六西格玛管理方法,可极大地提高静脉用药调配中心的工作效率,使工作流程更趋于标准化和规范化.

  8. 矿物掺合料对再生混凝土抗氯离子渗透性研究%Research on Recycled Concrete Resistance to Penetration of Chloride Ion by Adding Mineral Admixtures

    Institute of Scientific and Technical Information of China (English)

    姜健; 徐惠; 唐轶繁

    2015-01-01

    The test begins with preparation of cylindrical specimens about 100±1mm in diameter and 50± 2mm in height which are made of C25 normal concrete, C30 normal concrete, recycled concrete and modified recycled concrete by adding some mineral admixtures such as fly ash, silicon ash, steel fiber and polypropylene fiber etc. as the modified measures. Then it measures Cl-permeability coefficients of 40 days without external loads by RCM and studies Cl-diffusion coefficients of recycled concrete under different modified measures. The results show that the resistance of unmodified recycled concrete to Cl-permeability is poorer than that of normal concrete and there are pretty different Cl- diffusion coefficients; the resistance of normal concrete and recycled concrete to Cl- permeability can be improved with increase of strength grade; by adding fly ash and silicon ash in the proportion of 1:1 into recycled concrete, the resistance of modified recycled concrete to Cl- permeability can be improved in comparison to recycled concrete of the same strength grade but is lower than that of normal concrete of the same strength grade; by adding steel fiber or polypropylene fiber within the range of 0~1.0% on the premise of mixing fly ash and silicon ash, the resistance of modified recycled concrete to Cl-permeability can be improved a lot in comparison to recycled concrete of the same strength grade and is higher than that of normal concrete of the same strength grade; within the range, Cl- permeability coefficient of modified recycled concrete decreases rapidly as the amount of steel fiber or polypropylene fiber increases; adding polypropylene fiber is more effective than adding steel fiber within the range 0~1.0%on the premise of mixing fly ash and silicon ash.%以掺加粉煤灰、硅灰、钢纤维、聚丙烯纤维等矿物掺合料为改性措施,制备C25、C30普通混凝土、再生混凝土和改性再生混凝土的圆柱体试件,直径(100±1)mm,高度(50

  9. 矿物掺合料对再生混凝土抗氯离子渗透性研究%Research on Recycled Concrete Resistance to Penetration of Chloride Ion by Adding Mineral Admixtures

    Institute of Scientific and Technical Information of China (English)

    姜健; 徐惠; 唐轶繁

    2016-01-01

    The test begins with preparation of cylindrical specimens about(100 ± 1)mm in diameter and (50 ± 2)mm in height which are made of C25 normal concrete, C30 normal concrete, recycled concrete and modified recycled concrete by adding some mineral admixtures such as fly ash, silicon ash, steel fiber and polypropylene fiber etc. as the modified measures. Then it measures Cl- permeability coefficients of 40 days without external loads by RCM and studies Cl- diffusion coefficients of recycled concrete under different modified measures. The results show that the resistance of unmodified recycled concrete to Cl- permeability is poorer than that of normal concrete and there are pretty different Cl-diffusion coefficients; the resistance of normal concrete and recycled concrete to Cl- permeability can be improved with increase of strength grade; by adding fly ash and silicon ash in the proportion of 1:1 into recycled concrete, the resistance of modified recycled concrete to Cl- permeability can be improved in comparison to recycled concrete of the same strength grade but is lower than that of normal concrete of the same strength grade;by adding steel fiber or polypropylene fiber within the range of 0%~1.0%on the premise of mixing fly ash and silicon ash, the resistance of modified recycled concrete to Cl-permeability can be improved a lot in comparison to recycled concrete of the same strength grade and is higher than that of normal concrete of the same strength grade; within the range, Cl- permeability coefficient of modified recycled concrete decreases rapidly as the amount of steel fiber or polypropylene fiber increases;adding polypropylene fiber is more effective than adding steel fiber within the range 0%~1.0%on the premise of mixing fly ash and silicon ash.%以掺加粉煤灰、硅灰、钢纤维、聚丙烯纤维等矿物掺合料为改性措施,制备C25、C30普通混凝土、再生混凝土和改性再生混凝土的圆柱体试件,直径(100±1)mm,高度(50±2)mm

  10. 掺合料和水胶比对水泥基材料水化产物和力学性能的影响%Influence of admixture and water-cement ratio on hydration products and mechanical properties of cement-based materials

    Institute of Scientific and Technical Information of China (English)

    吴福飞; 侍克斌; 董双快; 陈亮亮; 慈军; 王欣; 张凯

    2016-01-01

    Admixture and water-cement ratio are important factors affecting the development of properties of cement mortar or concrete. In order to study the influence of admixtures and water-cement ratio on the hydration products and the mechanical properties of cement-based materials, the study combined hydration reaction mechanism of pure cement and silicate admixture, derived the formulae of hydration products, theoretical maximum mixing amount and total porosity of composite cement-based materials, and investigated the effects of mixing amount of cement mortar with fly ash, steel slag and lithium slag on total porosity, mechanical properties and hydration products. This paper designed 3 gradients of water-cement ratio (0.50, 0.42 and 0.34), 3 kinds of admixtures (lithium slag, fly ash and steel slag) and 2 contents (20% and 60%); the ratio of cementitious material to sand was 1:2.5, and then, molding specimen accorded with the mix of mortar in the triple mold and the mechanical properties of mortar were tested when specimen was cured to 1, 3, 7, 28 and 90 d. The results showed that, after the same content of fly ash, steel slag and lithium slag incorporation, the contents of hydration products of composite cementitious materials, i.e. calcium hydroxide (CH) and calcium silicate hydrate (CSH), and the total porosity were smaller than those of pure cement; when the water-cement ratio decreased from 0.50 to 0.34, the total porosity of cement mortar decreased from 16.0% to 9.3%, and the contents of CH and CSH increased for the compound cement-based materials with mixing amount of 5%, but the increments were not big; the porosity of fly ash, steel slag and lithium slag cement-based composite materials reduced from 16.6%, 17.2% and 16.0% to 9.9%, 10.9% and 9.3%, respectively. When the admixture amount increased to 10%, the variation of porosity and hydration products of the 3 kinds of mortar was different. The content of hydration products (CH and CSH) of composite

  11. Recent trend: Use of metakaolin as admixture: A review

    OpenAIRE

    Prof. R.M. Sawant; Dr. Y.M. Ghugal

    2015-01-01

    Due to worldwide infrastructural development, since 20th century use of concrete has tremendously increased which resulted in heavy manufacturing of cement. Production of cement results in heavy environmental pollution due to emission of CO2 gas. Also the raw materials used for the manufacturing of cement are quarried from the natural geological formations. Researchers have started working on partial supplementation of ordinary portland cement mineral or raw materials by naturally occuring, m...

  12. Complex admixtures of clathrate hydrates in a water desalination method

    Science.gov (United States)

    Simmons, Blake A.; Bradshaw, Robert W.; Dedrick, Daniel E.; Anderson, David W.

    2009-07-14

    Disclosed is a method that achieves water desalination by utilizing and optimizing clathrate hydrate phenomena. Clathrate hydrates are crystalline compounds of gas and water that desalinate water by excluding salt molecules during crystallization. Contacting a hydrate forming gaseous species with water will spontaneously form hydrates at specific temperatures and pressures through the extraction of water molecules from the bulk phase followed by crystallite nucleation. Subsequent dissociation of pure hydrates yields fresh water and, if operated correctly, allows the hydrate-forming gas to be efficiently recycled into the process stream.

  13. Recent trend: Use of metakaolin as admixture: A review

    Directory of Open Access Journals (Sweden)

    Prof. R.M. Sawant

    2015-12-01

    Full Text Available Due to worldwide infrastructural development, since 20th century use of concrete has tremendously increased which resulted in heavy manufacturing of cement. Production of cement results in heavy environmental pollution due to emission of CO2 gas. Also the raw materials used for the manufacturing of cement are quarried from the natural geological formations. Researchers have started working on partial supplementation of ordinary portland cement mineral or raw materials by naturally occuring, manufactured, or manmade waste. Various types of pozzolonic materials viz.fly ash, silica fume, metakaolin, blast furnace slag etc. are available which has cementeous properties. Blending these materials with ordinary portland cement can improve the cementing and mechanical properties of cement. These days use of metakaolin is tremendously gaining popularity in partial replacement of cement due to its fineness in improving various strengths and parameters of mortars and concrete.

  14. Detecting population admixture in honey bees of Serbia

    DEFF Research Database (Denmark)

    Nedic, Nebojsa; Francis, Roy Mathew; Stanisavljevic, Ljubisa;

    2014-01-01

    morphometrics and 122 bees were successfully analysed using 24 DNA microsatellite markers. A combination of methods including multivariate statistics and assignment tests (frequency-based and Bayesian) revealed the honey bees of this region to resemble the subspecies Apis mellifera macedonica, Apis mellifera...

  15. Early structure formation of foam concrete mix containing modifying admixture

    Directory of Open Access Journals (Sweden)

    A.B. Steshenko

    2015-03-01

    Full Text Available Cement based foam concrete of natural aging experiences high shrinkage of foam concrete mix in the formwork and shrinkage strain when drying. When managing the microstructure of the composite, namely the change (acceleration of the microstructure formation and reinforcement of the cement stone, significant decrease can be achieved in the values of shrinkage strain. The purpose of this research is to study the patterns of influence of the chrysotile asbestos fibers and the glyoxal crystalline on shrinkage deformations of cement based foam concrete of natural aging. The foam concrete mixture was produced by one-step technology in the laboratory mixer. Values of plastic shrinkage and plastic strength were determined during three hours after pouring the foam concrete mixture into a metal vessel. The microstructure investigation results have shown that introduction of chrysotile asbestos fibers in an amount of 2 % and glyoxal crystalline in an amount of 0.01 % by weight of cement provides a finely porous foam concrete structure with more uniform size closed pores, which are evenly distributed over the volume. Experimental studies have demonstrated that if chrysotile asbestos fibers are introduced in an amount of 2% and the crystalline glyoxal in an amount of 0.01 % by weight of cement it leads to decrease in plastic shrinkage by 40 to 29%, shrinkage when drying by 44 and 50% and growth in plastic strength by 63 and 45% respectively.

  16. Effect of Mineral Admixtures on Alkali-Silica Reaction

    Institute of Scientific and Technical Information of China (English)

    ZHANG Chengzhi; WANG Aiqin

    2008-01-01

    The influence of silica fume,slag and fly ash on alkali-silica reaction under the condition of 70℃ is studied.The results show that silica,slag and fly ash may inhibit alkali-silica reaction only under suitable content.When the content is less than 10%,silica fume does not markedly influence the expansion of alkali-silica reaction.When the content is 15%-20%,silica fume only may delay the expansion of alkali-silica reaction.When the content is 30%-70%,slag may only delay the expansion of alkali-silica reaction,but cannot inhibit the expansion of alkali-silica reaction.When the content is 10%,fly ash does not markedly influence the expansion of alkali-silica reaction.When the content is 20%-30%,fly ash may only delay the expansion of alkali-silica reaction,but cannot inhibit the expansion of alkali-silica reaction.When the content is over 50%,it is possible that fly ash can inhibit effectively alkali-silica reaction.

  17. Admixtures in Spent Plutonium Sources and Gamma-Radiation

    Directory of Open Access Journals (Sweden)

    Inga Pelanytė

    2011-04-01

    Full Text Available The isotopic composition of several spent smoke detectors containing plutonium has been investigated. The article also presents the calculated results of 241Am and 241Pu activities in smoke detectors. The received values vary from (0.934±0.028 MBq to (91.2±4.6 MBq. The eguivalent dose rate of the established gamma radiation vary from 220 nSv/h to 500 nSv/h. A dose caused by artificial radionuclides in spent smoke detectors was evaluated and compared in the article. It has been found out that due to smoke detectors, an annual dose varies from 0.06 mSv to 0.31 mSv. Article in Lithuanian

  18. Leveraging population admixture to characterize the heritability of complex traits

    DEFF Research Database (Denmark)

    Zaitlen, Noah; Pasaniuc, Bogdan; Sankararaman, Sriram; Bhatia, Gaurav; Zhang, Jianqi; Gusev, Alexander; Young, Taylor; Tandon, Arti; Pollack, Samuela; Vilhjálmsson, Bjarni Jóhann; Assimes, Themistocles L; Berndt, Sonja I; Blot, William J; Chanock, Stephen; Franceschini, Nora; Goodman, Phyllis G; He, Jing; Hennis, Anselm J M; Hsing, Ann; Ingles, Sue A; Isaacs, William; Kittles, Rick A; Klein, Eric A; Lange, Leslie A; Nemesure, Barbara; Patterson, Nick; Reich, David; Rybicki, Benjamin A; Stanford, Janet L; Stevens, Victoria L; Strom, Sara S; Whitsel, Eric A; Witte, John S; Xu, Jianfeng; Haiman, Christopher; Wilson, James G; Kooperberg, Charles; Stram, Daniel; Reiner, Alex P; Tang, Hua; Price, Alkes L

    2014-01-01

    -wide ancestry proportion. Our approach is not susceptible to biases caused by epistasis or shared environment. We applied this approach to the analysis of 13 phenotypes in 21,497 African-American individuals from 3 cohorts. For height and body mass index (BMI), we obtained h(2) estimates of 0.55 ± 0.09 and 0...

  19. Chloroplast heterogeneity and historical admixture within the genus Malus

    Science.gov (United States)

    Premise of the study: We examined chloroplast DNA sequence variation in 412 samples representing 30 Malus species (including Malus x domestica Borkh.). Malus wild species are of particular interest for providing novel alleles and traits in apple breeding programs, yet the taxonomic status of these s...

  20. Origins, admixture and founder lineages in European Roma.

    Science.gov (United States)

    Martínez-Cruz, Begoña; Mendizabal, Isabel; Harmant, Christine; de Pablo, Rosario; Ioana, Mihai; Angelicheva, Dora; Kouvatsi, Anastasia; Makukh, Halyna; Netea, Mihai G; Pamjav, Horolma; Zalán, Andrea; Tournev, Ivailo; Marushiakova, Elena; Popov, Vesselin; Bertranpetit, Jaume; Kalaydjieva, Luba; Quintana-Murci, Lluis; Comas, David

    2016-06-01

    The Roma, also known as 'Gypsies', represent the largest and the most widespread ethnic minority of Europe. There is increasing evidence, based on linguistic, anthropological and genetic data, to suggest that they originated from the Indian subcontinent, with subsequent bottlenecks and undetermined gene flow from/to hosting populations during their diaspora. Further support comes from the presence of Indian uniparentally inherited lineages, such as mitochondrial DNA M and Y-chromosome H haplogroups, in a significant number of Roma individuals. However, the limited resolution of most genetic studies so far, together with the restriction of the samples used, have prevented the detection of other non-Indian founder lineages that might have been present in the proto-Roma population. We performed a high-resolution study of the uniparental genomes of 753 Roma and 984 non-Roma hosting European individuals. Roma groups show lower genetic diversity and high heterogeneity compared with non-Roma samples as a result of lower effective population size and extensive drift, consistent with a series of bottlenecks during their diaspora. We found a set of founder lineages, present in the Roma and virtually absent in the non-Roma, for the maternal (H7, J1b3, J1c1, M18, M35b, M5a1, U3, and X2d) and paternal (I-P259, J-M92, and J-M67) genomes. This lineage classification allows us to identify extensive gene flow from non-Roma to Roma groups, whereas the opposite pattern, although not negligible, is substantially lower (up to 6.3%). Finally, the exact haplotype matching analysis of both uniparental lineages consistently points to a Northwestern origin of the proto-Roma population within the Indian subcontinent. PMID:26374132

  1. Growth of fractal structures in flames with silicon admixture

    OpenAIRE

    Smirnov, B. M.; Dutka, M.; van Essen, V. M.; Gersen, S.; Visser, P.; Vainchtein, D.; De Hosson, J.Th.M.; Levinsky, H.B.; Mokhov, A. V.

    2012-01-01

    Transmission electron microscopy (TEM) measurements and theoretical analysis are combined to construct the physical picture of formation of SiO2 fractal aggregates in a methane/hexamethyldisiloxane/air atmospheric pressure flame. The formation of SiO2 fractal aggregates is described as a multistage process. The first stage is combustion of fuel in a narrow flame front region with formation of main combustion products including SiO2 molecules. Further downstream SiO2 molecules join in liquid n...

  2. Effect of aluminium phosphate as admixture on oxychloride cement

    Indian Academy of Sciences (India)

    M P S Chandrawat; R N Yadav

    2000-02-01

    The effect of admixing of aluminium phosphate on oxychloride cement in the matrix has been investigated. It is shown that aluminium phosphate retards the setting process of the cement and improves water-tightness.

  3. High-resolution gene mapping using admixture linkage disequilibrium

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    This note reports simulation study on the rate of decay in linkage dis equilibrium (LD) in mixed populations over multiple discrete generations and explores the usefulness of the LD analysis in high-resolution gene mapping. The results indicate that the smaller the recombination fraction and the fewer generati ons since admixtureevent, the higher power of the approach in gene mapping. The expected estimate of recombination fraction would give an estimate that is slig htly biased upwards, if relevant genes are in tight linkage. The estimated recom bination fraction is usually larger than the true value within 2-5 generations. From generations 10-20, the mean estimates are in good agreement with the true value. The method presented here enables estimation of means and corresponding confidence intervals of the recombination fraction at any number of generations.

  4. Structure and composition of admixture precipitates of nickel in silicon

    International Nuclear Information System (INIS)

    Structure and composition of precipitates of nickel atoms in monocrystalline silicon were investigated by electron-probe microanalysis. precipitates were found to consist of silicides of nickel involving some technological impurities and have needle, disk and ball forms, which can disintegrate under influence of external pressures. Because of distinct environmental conditions around precipitates of various forms their disintegration also differs from each other and it leads to corresponding alteration of crystals electrophysical parameter. (author)

  5. Strength properties of sandy soil-cement admixtures

    OpenAIRE

    da Fonseca, AV; Cruz, RC; Consoli, NC

    2009-01-01

    Soil stabilization with cement is a good solution for the construction of subgrades for roadway and railway lines, especially under the platforms and mostly in transition zones between embankments and rigid structures, where the mechanical properties of supporting soils are very influential. These solutions are especially attractive in line works where other ground improvement techniques are extensive and, therefore, very expensive. On the other hand, the economic and environmental costs of s...

  6. Early structure formation of foam concrete mix containing modifying admixture

    OpenAIRE

    A.B. Steshenko; A.I. Kudyakov

    2015-01-01

    Cement based foam concrete of natural aging experiences high shrinkage of foam concrete mix in the formwork and shrinkage strain when drying. When managing the microstructure of the composite, namely the change (acceleration) of the microstructure formation and reinforcement of the cement stone, significant decrease can be achieved in the values of shrinkage strain. The purpose of this research is to study the patterns of influence of the chrysotile asbestos fibers and the glyoxal crystal...

  7. 静脉营养液中加入肝素钠预防早产儿PICC导管堵塞的1例报告%Heparin Added in Total Nutrient Admixture for Preventing Peripherally Inserted Central Catheter Occlusion in Neonate: A Case Report

    Institute of Scientific and Technical Information of China (English)

    万兴丽; 曾力楠

    2012-01-01

    Objective To make an individualized administration scheme via evidence-based medicine methods, namely adding heparin into the total nutrient admixture (TNA) solution, so as to help a neonate to prevent the occlusion of peripherally inserted central catheter (PICC). Methods After carefully assessing the condition of neonate, this clinical issue was put forward in accordance with the PICO principles. Randomized controlled trials (RCTs) and systematic reviews on neonates' PICC occlusion were collected from The Cochrane Library, CCTR, DARE, NGC, MEDLINE (Ovid) and CBM from inception to 2011. The clinical intervention scheme was finally made after the assessment of the retrieved evidence and neonate's physiological condition. Results A total of 4 RCTs and 1 systematic review related to the issues were identified. The following scheme was finally made for the neonate through the assessment of the retrieved evidence and combination of intentions of the patient's family members: heparin (0.5 U/mL) was added into TNA to prevent PICC occlusion. During the application, blood routine test and blood coagulation were monitored, and the catheter opening time and extubation reason were recorded. Through the above treatment, the neonate successfully completed the treatment before extubation. The time of both PICC detaining and opening was 20 days in total, and there were no PICC occlusion, no catheter thrombosis, and no catheter related bloodstream infection. Moreover, no observation showed throm-bopenia and aggravated coagulation disorders resulted from heparin. Conclusion The evidence-based medicine method is an effective way to make reasonable heparin scheme for neonate, so as to prevent PICC occlusion, reduce catheter thrombosis, decrease risks of catheter related blood circulation infection, assure successful completion of treatment, and guarantee the safety of patients.%目的 借助循证医学方法为1例经外周静脉穿刺中心静脉导管(PICC)输注全合一静脉

  8. The influence of cement type and admixture on life span of reinforced concrete utility poles subjected to the high salinity environment of Northeastern Brazil, studied by corrosion potential testing A influência do tipo de cimento e adição na vida útil de postes de concreto armado submetidos ao ambiente de alta salinidade do Nordeste do Brasil, estudada pela técnica de potencial de corrosão

    Directory of Open Access Journals (Sweden)

    A. Joukoski

    2004-03-01

    Full Text Available Reinforced concrete structures installed in coastal zones have constantly been threatened by environmental damaging elements. The chloride ion is known as one of the most aggressive of these elements, causing, among other damages, corrosion of the steel reinforcement and then degradation of the concrete matrix. The goal of this work was to determine the influence of cement type on the resistance and durability of reinforced concrete samples with 25 mm cover thickness, when submitted to aging in a 3.4% sodium chloride aqueous solution and in a high salinity marine environment. Reinforced concrete light poles were cast following the same batching procedures, and after the curing period, they were exposed to atmosphere in a corrosion station near Aracaju, Sergipe State, Northeastern Brazil's coast. Two concrete mixtures were made using CPII-F 32 (filler-modified Portland cement: a mix with no admixture and a mix with addition of 8% silica fume swapping fine aggregates. Another mixture was batched with CPV-ARI RS (high-early-strength Portland cement, with sulfur resistance. All the three mixtures were designed with cement content of about 350 kg/m³. The performance of the structures was evaluated from the results of physicochemical, mechanical and electrochemical testing, after over a year of natural aging. Corrosion potentials of the reinforced concrete samples and of the cast utility poles were measured in terms of the aging time at the natural environment and under chloride ion accelerated aging at laboratory. The half-cell potential measurements showed that the best results were obtained from the mixture containing CPII-F 32 cement and silica fume, followed by the concrete made with CPV-ARI RS cement. The mixture batched with CPII-F 32 cement without admixture presented the worst durability performance.Estruturas de concreto armado instaladas em zonas costeiras têm sido constantemente ameaçadas por elementos ambientais nocivos. O íon cloreto

  9. Compressive Creep of Prestressed Concrete Mixtures With and Without Mineral Admixtures

    OpenAIRE

    Meyerson, Richard

    2001-01-01

    Concrete experiences volume changes throughout its service life. When loaded, concrete experiences an instantaneous recoverable elastic deformation and a slow inelastic deformation called creep. Creep of concrete is composed of two components, basic creep, or deformation under load without moisture loss and drying creep, or deformation under drying conditions only. Deformation of concrete in the absence of applied load is often called shrinkage. The deformation due to creep is attrib...

  10. Next generation haplotyping to decipher nuclear genomic interspecific admixture in Citrus species: analysis of chromosome 2

    OpenAIRE

    Curk, Franck; Ancillo, Gema; Garcia-Lor, Andres; Luro, François; Perrier, Xavier; Jacquemoud-Collet, Jean-Pierre; Navarro, Luis; Ollitrault, Patrick

    2014-01-01

    Background The most economically important Citrus species originated by natural interspecific hybridization between four ancestral taxa (Citrus reticulata, Citrus maxima, Citrus medica, and Citrus micrantha) and from limited subsequent interspecific recombination as a result of apomixis and vegetative propagation. Such reticulate evolution coupled with vegetative propagation results in mosaic genomes with large chromosome fragments from the basic taxa in frequent interspecific heterozygosity....

  11. Sequencing of diverse mandarin, pummelo and orange genomes reveals complex history of admixture during citrus domestication

    OpenAIRE

    Wu, G. Albert; Prochnik, Simon; Jenkins, Jerry; Salse, Jerome; Hellsten, Uffe; Murat, Florent; Perrier, Xavier; Ruiz, Manuel; Scalabrin, Simone; Terol, Javier; Takita, Marco Aurelio; Labadie, Karine; Poulain, Julie; Couloux, Arnaud; Jabbari, Kamel

    2014-01-01

    Cultivated citrus are selections from, or hybrids of, wild progenitor species whose identities and contributions to citrus domestication remain controversial. Here we sequence and compare citrus genomes-a high-quality reference haploid clementine genome and mandarin, pummelo, sweet-orange and sour-orange genomes- and show that cultivated types derive from two progenitor species. Although cultivated pummelos represent selections from one progenitor species, Citrus maxima, cultivated mandarins ...

  12. Use of Cement-Sand Admixture in Laterite Brick Production for Low Cost Housing

    Directory of Open Access Journals (Sweden)

    Isaac Olufemi AGBEDE

    2008-06-01

    Full Text Available Laterite was modified with 45% sand content by dry weight and stabilized with up to 9% cement content respectively and used in the production of 330 mm × 150 mm × 150 mm bricks through the application of a pressure of 3 N/mm2 with a brick moulding machine. Results showed that laterite used in this study cannot be stabilized for brick production within the economic cement content of 5% specified for use in Nigeria. However, bricks made with laterite admixed with 45% sand and 5% cement attained a compressive strength of 1.80 N/mm2 which is greater than the specified minimum strength value of 1.65 N/mm2. Cost comparison of available walling materials in Makurdi metropolis showed that the use of bricks made from 45% sand and 5% cement resulted in a saving of 30 - 47% when compared with the use of sandcrete blocks while the use of fired clay bricks resulted in a savings of 19% per square meter of wall. The study therefore recommends the use of laterite bricks in Makurdi and other locations because it is more economical and environmental friendly than fired clay bricks.

  13. Investigating the Mechanical Properties of High Performance Concrete with a Steel Fibre Admixture

    Directory of Open Access Journals (Sweden)

    Karim M.A.

    2014-01-01

    Full Text Available This paper presents the findings of an experimental investigation of the mechanical properties of concrete containing steel fibre. In the experimental investigation, the properties of steel fibre used in high strength concrete were assessed through 3 different mixes. Steel fibre was added into concrete in percentages of 0% (control, 0.6%, and 1.8%. These different types of mixes were then tested after durations of 3 days, 7 days, 14 days, and 28 days. Three cube specimens and three prism specimens were prepared for each test. In total, 36 cubes specimens and 36 prisms specimens were prepared and tested. The following tests were performed: workability test (slump test, density test, ultrasonic pulse velocity test, compressive strength test, flexural test, and water absorption test. The experimental results of this study indicate that the inclusion of steel fibres in concrete enhances the mechanical properties of high performance concrete and could reduce the severity of cracking problems for normal and high-rise buildings.

  14. Investigating the Mechanical Properties of High Performance Concrete with a Steel Fibre Admixture

    OpenAIRE

    Karim M.A.; Abas Noor Faisal; Othuman Mydin M.A.

    2014-01-01

    This paper presents the findings of an experimental investigation of the mechanical properties of concrete containing steel fibre. In the experimental investigation, the properties of steel fibre used in high strength concrete were assessed through 3 different mixes. Steel fibre was added into concrete in percentages of 0% (control), 0.6%, and 1.8%. These different types of mixes were then tested after durations of 3 days, 7 days, 14 days, and 28 days. Three cube specimens and three prism spe...

  15. The Effect of a Plasticizing Admixture on the Properties of Hardened Concrete

    OpenAIRE

    Anastasija Abasova; Džigita Nagrockienė

    2012-01-01

    Concrete is material obtained mixing matrix material, coarse and small aggregates and water along with additives acquiring necessary properties of hardening. The quality and properties of raw material used for manufacturing concrete, V/C ratio and the uniformity of the compaction of the mixture lead to the fundamental properties of concrete. The compressive strength of concrete is one of the most important properties of concrete. The article deals with the impact of plasticizers on the struct...

  16. Concentration of gas admixture from line source in flow over two-dimensional hill

    Czech Academy of Sciences Publication Activity Database

    Antoš, Pavel; Jonáš, Pavel; Mazur, Oton; Uruba, Václav

    Antalya : HEFAT, 2010 - (Meyer, J.), s. 2151-2153 ISBN 978-1-86854-818-7. [International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics /7./. Antalya (TR), 19.07.2010-21.07.2010] R&D Projects: GA ČR GPP101/10/P556 Institutional research plan: CEZ:AV0Z20760514 Keywords : binary gas concentration * hot wire Subject RIV: BK - Fluid Dynamics

  17. Complex history of admixture during citrus domestication revealed by genome analysis

    Energy Technology Data Exchange (ETDEWEB)

    Wu, G. Albert; Prochnik, Simon; Jenkins, Jerry; Salse, Jerome; Hellsten, Uffe; Murat, Florent; Perrier, Xavier; Ruiz, Manuel; Scalabrin, Simone; Terol, Javier; Takita, Marco Aur& #233; lio,; Labadie, Karine; Poulain, Julie; Couloux, Arnaud; Jabbari, Kamel; Cattonaro, Federica; Fabbro, Cristian Del; Pinosio, Sara; Zuccolo, Andrea; Chapman, Jarrod; Grimwood, Jane; Tadeo, Francisco; Estornell, Leandro H.; Mu?oz-Sanz, Juan V.; Ibanez, Victoria; Herrero-Ortega, Amparo; Aleza, Pablo; P& #233; rez, Juli& #225; n P& #233; rez,; Ramon, Daniel; Brunel, Dominique; Luro, Francois; Chen, Chunxian; Farmerie, William G.; Desany, Brian; Kodira, Chinnappa; Mohiuddin, Mohammed; Harkins, Tim; Fredrikson, Karin; Burns, Paul; Lomsadze, Alexandre; Borodovsky, Mark; Reforgiato, Giuseppe; Freitas-Astua, Juliana; Quetier, Francis; Navarro, Luis; Roose, Mikeal; Wincker, Patrick; Schmutz, Jeremy; Morgante, Michele; Machado, Marcos Antonio; Talon, Manuel; Jaillon, Olivier; Ollitrault, Patrick; Gmitter, Frederick; Rokhsar, Daniel

    2014-06-30

    Although Citrus is the most globally significant tree fruit, its domestication history is poorly understood. Cultivated citrus types are believed to comprise selections from and/or hybrids of several wild progenitor species, but the identities of these progenitors, and their contribution to modern cultivars, remain controversial. Here we report the genomes of a collection of mandarins, pummelos, and oranges, including a high quality reference sequence from a haploid Clementine mandarin. By comparative genome analysis we show that these cultivated types can be derived from two progenitor species. Cultivated pummelos represent selections from a single progenitor species C. maxima. Unexpectedly, however, we find that cultivated mandarins are introgressions of C. maxima into a distinct second population that we identify with the ancestral wild mandarin species C. reticulata. Sweet and sour oranges are found to be interspecific hybrids. Sweet orange, the most widely cultivated citrus, arose as the offspring of previously admixed individuals. In contrast, sour (or Seville) orange is an F1 hybrid of pure C. maxima and C. reticulata parents, implying that wild mandarins were part of the early breeding germplasm. Surprisingly, we also find that a wild Chinese mandarin from Mangshan, China shows substantial sequence divergence from C. reticulata and appears to represent a distinct taxon. Understanding the relationships and phylogeny of cultivated citrus through genome analysis will clarify taxonomic relationships and enable previously inconceivable opportunities for sequence-directed genetic improvement. Citrus are widely consumed worldwide as juice or fresh fruit, providing important sources of vitamin C and other health-promoting compounds. Global production in 2012 exceeded 86 million metric tons, with an estimated value of US$9 billion (http://www.fas.usda.gov/psdonline/circulars/citrus.pdf). The very narrow genetic diversity of cultivated citrus makes it highly vulnerable to disease outbreaks, including citrus greening disease (also known as Huanglongbing) that is rapidly spreading throughout the world's major citrus producing regions1. Understanding the population genomics and domestication of citrus will enable strategies for improvements to citrus including resistance to greening and other diseases. The domestication and distribution of edible citrus types began several thousand years ago in Southeast Asia and spread globally following ancient land and sea routes. The lineages that gave rise to most modern cultivated varieties, however, are lost in undocumented antiquity, and their identities remain controversial2, 3. Several features of Citrus biology and cultivation make deciphering these origins difficult. Cultivated varieties are typically propagated clonally by grafting and through asexual seed production (apomixis via nucellar polyembryony) to maintain desirable combinations of traits (Fig. 1). Thus many important cultivar groups have characteristic basic genotypes that presumably arose through interspecific hybridization and/or successive introgressive hybridizations of wild ancestral species. These domestication events predated the global expansion of citrus cultivation by hundreds or perhaps thousands of years, with no record of the domestication process. Diversity within such groups arises through accumulated somatic mutations, generally without sexual recombination, either as limb sports on trees or variants among apomictic seedling progeny. Two wild species are believed to have contributed to domesticated pummelos, mandarins and oranges. Based on morphology and genetic markers, pummelos have generally been identified with the wild species C. maxima (Burm.) Merrill that is indigenous to Southeast Asia. Although mandarins are similarly widely identified with the species C. reticulata Blanco 4-6, wild populations of C. reticulata have not been definitively described. Various authors have taken dif

  18. Generation of silicon nanostructures by atmospheric microplasma jet: the role of hydrogen admixture

    Czech Academy of Sciences Publication Activity Database

    Barwe, B.; Stein, A.; Cibulka, Ondřej; Pelant, Ivan; Ghanbaja, J.; Belmonte, T.; Benedikt, J.

    2015-01-01

    Roč. 12, č. 2 (2015), s. 132-140. ISSN 1612-8850 Institutional support: RVO:68378271 Keywords : atmospheric pressure plasmas * HRTEM * microplasmas * photoluminescence * silicon nanocrystals Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 2.453, year: 2014

  19. Probing background ionization: Positive streamers with varying pulse repetition rate and with a radioactive admixture

    OpenAIRE

    Nijdam, S.; Wormeester, G.; van Veldhuizen, E. M.; Ebert, U.

    2011-01-01

    Positive streamers need a source of free electrons ahead of them to propagate. A streamer can supply these electrons by itself through photo-ionization, or the electrons can be present due to external background ionization. Here we investigate the effects of background ionization on streamer propagation and morphology by changing the gas composition and the repetition rate of the voltage pulses, and by adding a small amount of radioactive Krypton 85. We find that the general morphology of a p...

  20. Hydraulic activity of belite cement from class C coal fly ash. Effect of curing and admixtures

    Directory of Open Access Journals (Sweden)

    Guerrero, A.

    2006-09-01

    Full Text Available The effect of curing method and a water-reducing additive on the hydraulic activity of high lime content (ASTM type C fly ash belite cement (FABC-2-W is reported. A class C fly ash was subjected to hydrothermal treatment and subsequent calcination to synthesize FABC. Hydraulic activity was evaluated in the cement paste over 180 days from the physically bound water content as determined by thermogravimetric analysis and the degree of hydration, in turn found with X-ray diffraction (XRD analysis. Mechanical strength, porosity and pore size distribution were also studied in equivalent mortar samples.En este trabajo se discute la influencia del tipo de curado y de un aditivo reductor de la demanda de agua en la actividad hidráulica de un cemento belítico de cenizas volantes de alto contenido en cal denominado (CBCV-2-A. Este cemento ha sido sintetizado por una ruta húmeda hidrotermal con posterior calcinación, empleando ceniza volante de alto contenido en cal (ASTM tipo C como materia prima. La actividad hidráulica se ha estudiado en la pasta de cemento, durante un periodo de 180 días, por medio del contenido de agua combinada, determinada por análisis termogravimétrico, y el grado de hidratación por difracción de rayos X (DRX. La resistencia mecánica y la porosidad total y distribución de tamaño de poro se han estudiado en probetas equivalentes de mortero

  1. The long term effect on cement mortar by admixture of spray drying absorption products

    International Nuclear Information System (INIS)

    Preliminary investigations have shown that the substitutions of up to 10% fly ash (FA), with spray drying absorption products (SDA), in cement mortars (cement: 80% rapid portland cement (RPC), 10-20% FA, 0-10% SDA) results in low early strength of the same magnitude as in mortar with 80% RPC + 20% FA. Use of the modified instructions for preparation of mortar prisms containing SDA resulted in satisfactory early strengths. A series of mortar prisms with increasing content of SDA (x% RPC, (100-x)% SDA in cements; 0 80% cannot be stored wet. The effects on mortars of the individual constituents of the SDA-products are studied by XRD, development in strength and density. Fragments of 2 year old SDA containing cement mortars and SDA containing concrete from a parking place have been studied

  2. Consistent long-range linkage disequilibrium generated by admixture in a Bantu-Semitic hybrid population

    OpenAIRE

    Wilson, J F; Goldstein, D. B.

    2000-01-01

    Both the optimal marker density for genome scans in case-control association studies and the appropriate study design for the testing of candidate genes depend on the genomic pattern of linkage disequilibrium (LD). In this study, we provide the first conclusive demonstration that the diverse demographic histories of human populations have produced dramatic differences in genomewide patterns of LD. Using a panel of 66 markers spanning the X chromosome, we show that, in the Lemba, a Bantu-Semit...

  3. Search for the admixture of heavy neutrinos in the recoil spectra of {sup 37}Ar decay

    Energy Technology Data Exchange (ETDEWEB)

    Hindi, M.M.; Kozub, R.L.; Miocinovic, P. [Department of Physics, Tennessee Technological University, Cookeville, Tennessee 38505 (United States); Avci, R.; Zhu, L. [Department of Physics, Montana State University, Bozeman, Montana 59717 (United States); Hussein, A.H. [Physics Program, University of Northern British Columbia, Prince George, British Columbia, V2N 4Z9 (CANADA)

    1998-10-01

    Neutrino-induced recoil spectra of {sup 37}Cl ions produced in the electron capture (EC) decay of {sup 37}Ar were measured and searched for the presence of massive neutrinos admixed to the dominant electron neutrino. Fractions of a monolayer of {sup 37}Ar were physisorbed on Au and on several underlayers of {sup 40}Ar adsorbed on both Au and graphite substrates cooled to {le}20 K under ultrahigh vacuum conditions. Time-of-flight spectra of the recoiling ions were recorded in coincidence with x rays and Auger electrons emitted following the EC decay. By searching these spectra for peaks with energies between 7.6 eV and 3.6 eV upper limits were placed on the mixing probability of the electron neutrino with heavy neutrinos in the 370{endash}640 keV mass range. These limits vary from 1 to 4{percent}, at the 90{percent} confidence level. {copyright} {ital 1998} {ital The American Physical Society}

  4. Analysis of quality of welder's working atmosphere during application of alloyed filler admixtures

    International Nuclear Information System (INIS)

    The mechanism is described of the development of welding aerosols and the kinetics of harmful chemical compounds in the human organism. Model welding was implemented using welding rectifier WTU 315-3. Used in the experiments were austenitic coated electrode and wires for welding in the control argon atmosphere using the MIG technology. Trapped aerosols were irradiated with fast neutrons from a linear charged particle accelerator operating as a neutron generator. The neutron flux was 109s-1. A coaxial Ge(Li) detector was used for the detection of gamma spectra. The results of the analysis of aerosols are summed up in tables. It was found that fast neutron activation analysis of welding aerosols is reliable for the determination of F, Mn, Si, Na, Ba, Cr and V; lower accuracy was achieved in the determination of Fe, Co, Mo, K, Al and other elements. It is not suitable for the determination of Ni. (E.S.). 7 tabs., 7 figs., 21 refs

  5. Male Lineages in Brazil: Intercontinental Admixture and Stratification of the European Background

    Science.gov (United States)

    Geppert, Maria; Roewer, Lutz; Palha, Teresinha; Alvarez, Luis; Ribeiro-dos-Santos, Ândrea; Santos, Sidney

    2016-01-01

    The non-recombining nature of the Y chromosome and the well-established phylogeny of Y-specific Single Nucleotide Polymorphisms (Y-SNPs) make them useful for defining haplogroups with high geographical specificity; therefore, they are more apt than the Y-STRs to detect population stratification in admixed populations from diverse continental origins. Different Y-SNP typing strategies have been described to address issues of population history and movements within geographic territories of interest. In this study, we investigated a set of 41 Y-SNPs in 1217 unrelated males from the five Brazilian geopolitical regions, aiming to disclose the genetic structure of male lineages in the country. A population comparison based on pairwise FST genetic distances did not reveal statistically significant differences in haplogroup frequency distributions among populations from the different regions. The genetic differences observed among regions were, however, consistent with the colonization history of the country. The sample from the Northern region presented the highest Native American ancestry (8.4%), whereas the more pronounced African contribution could be observed in the Northeastern population (15.1%). The Central-Western and Southern samples showed the higher European contributions (95.7% and 93.6%, respectively). The Southeastern region presented significant European (86.1%) and African (12.0%) contributions. The subtyping of the most frequent European lineage in Brazil (R1b1a-M269) allowed differences in the genetic European background of the five Brazilian regions to be investigated for the first time. PMID:27046235

  6. PERFORMANCE OF MICROWAVE INCINARATED RICE HUSK ASH AND USED ENGINE OIL AS A GREEN CONCRETE ADMIXTURES

    OpenAIRE

    B. SALMIA; M. F. Nuruddin; Shafiq, N; M. K. NUR LIYANA; S. H. A. TALIB

    2015-01-01

    The utilization of waste materials in the construction industry is a novel approach let alone if these materials can further enhance the durability of the structures. Amongst the waste materials identified to be incorporated in this study is Rice Husk Ash (RHA) and Used Engine Oil (UEO). Productions of these waste materials are colossal with annual volume of 1.35 billion gallon and 40 million tons of used engine oil and rice husk respectively. The main aim of this research is to establish ...

  7. Biogeographic Ancestry, Self-Identified Race, and Admixture-Phenotype Associations in the Heart SCORE Study

    OpenAIRE

    Halder, Indrani; Kip, Kevin E.; Mulukutla, Suresh R.; Aiyer, Aryan N.; Marroquin, Oscar C; Huggins, Gordon S.; Reis, Steven E.

    2012-01-01

    Large epidemiologic studies examining differences in cardiovascular disease (CVD) risk factor profiles between European Americans and African Americans have exclusively used self-identified race (SIR) to classify individuals. Recent genetic epidemiology studies of some CVD risk factors have suggested that biogeographic ancestry (BGA) may be a better predictor of CVD risk than SIR. This hypothesis was investigated in 464 African Americans and 771 European Americans enrolled in the Heart Strate...

  8. Software packages for simulating groundwater flow and the spreading of soluble and insoluble admixtures in aquifers

    International Nuclear Information System (INIS)

    Software programs are described designed for solving hydrogeological and environmental problems related to the analysis and prediction of groundwater flow and the spreading of solutes and insolubles in the saturated zones. The software package GWFS (Ground Water Flow Simulation) allows for simulating steady-state and unsteady-state flow in confined, unconfined, and confined-unconfined multi-layer and quasi-3D isotropic and anisotropic aquifer systems. Considered are intra-layer sources and sinks, infiltration, inter-layer leakages, the interrelationships with surface reservoirs and streams, interrelationships with the drains, aquifer discharge to surface sources. The MTS (Mass Transport Simulation) package is designed for solving solute transport problems. Taken into account is convective transport, hydrodynamic dispersion and diffusion, linear equilibrium sorption. The method of characteristics is being implemented here using the ''particles-in-cells'' scheme in which the transport is modeled with the help of tracers. The software package OWFS (Oil-Water Flow Simulation) is designed for the simulation of hydrocarbon (oil-water) migration in aquifers

  9. Genetic structure of marine Borrelia garinii and population admixture with the terrestrial cycle of Lyme borreliosis

    OpenAIRE

    Gomez-Diaz, E.; Boulinier, T.; Sertour, N.; Cornet, M.; Ferquel, E.; McCoy, Karen

    2011-01-01

    Despite the importance of population structure for the epidemiology of pathogenic bacteria, the spatial and ecological heterogeneity of these populations is often poorly characterized. Here, we investigated the genetic diversity and population structure of the Lyme borreliosis (LB) spirochaete Borrelia garinii in its marine cycle involving colonial seabirds and different host races of the seabird tick Ixodes uriae. Multilocus sequence analyses (MLSA) on eight chromosomal and two plasmid loci ...

  10. Male Lineages in Brazil: Intercontinental Admixture and Stratification of the European Background.

    Science.gov (United States)

    Resque, Rafael; Gusmão, Leonor; Geppert, Maria; Roewer, Lutz; Palha, Teresinha; Alvarez, Luis; Ribeiro-dos-Santos, Ândrea; Santos, Sidney

    2016-01-01

    The non-recombining nature of the Y chromosome and the well-established phylogeny of Y-specific Single Nucleotide Polymorphisms (Y-SNPs) make them useful for defining haplogroups with high geographical specificity; therefore, they are more apt than the Y-STRs to detect population stratification in admixed populations from diverse continental origins. Different Y-SNP typing strategies have been described to address issues of population history and movements within geographic territories of interest. In this study, we investigated a set of 41 Y-SNPs in 1217 unrelated males from the five Brazilian geopolitical regions, aiming to disclose the genetic structure of male lineages in the country. A population comparison based on pairwise FST genetic distances did not reveal statistically significant differences in haplogroup frequency distributions among populations from the different regions. The genetic differences observed among regions were, however, consistent with the colonization history of the country. The sample from the Northern region presented the highest Native American ancestry (8.4%), whereas the more pronounced African contribution could be observed in the Northeastern population (15.1%). The Central-Western and Southern samples showed the higher European contributions (95.7% and 93.6%, respectively). The Southeastern region presented significant European (86.1%) and African (12.0%) contributions. The subtyping of the most frequent European lineage in Brazil (R1b1a-M269) allowed differences in the genetic European background of the five Brazilian regions to be investigated for the first time. PMID:27046235

  11. Influence of the proton irradiation on the surface states density in MIS structures with Rh admixture

    International Nuclear Information System (INIS)

    Influence of the proton irradiation on the insulator-impurity-semiconductor interface parameters of MIS structures was investigated. It was shown that Si-SiO2 interface layers in MIS structures under the action of proton irradiation were more than in ones without Rh. (author). 9 refs.; 1 fig

  12. The population genomic landscape of human genetic structure, admixture history and local adaptation in Peninsular Malaysia.

    Science.gov (United States)

    Deng, Lian; Hoh, Boon Peng; Lu, Dongsheng; Fu, Ruiqing; Phipps, Maude E; Li, Shilin; Nur-Shafawati, Ab Rajab; Hatin, Wan Isa; Ismail, Endom; Mokhtar, Siti Shuhada; Jin, Li; Zilfalil, Bin Alwi; Marshall, Christian R; Scherer, Stephen W; Al-Mulla, Fahd; Xu, Shuhua

    2014-09-01

    Peninsular Malaysia is a strategic region which might have played an important role in the initial peopling and subsequent human migrations in Asia. However, the genetic diversity and history of human populations--especially indigenous populations--inhabiting this area remain poorly understood. Here, we conducted a genome-wide study using over 900,000 single nucleotide polymorphisms (SNPs) in four major Malaysian ethnic groups (MEGs; Malay, Proto-Malay, Senoi and Negrito), and made comparisons of 17 world-wide populations. Our data revealed that Peninsular Malaysia has greater genetic diversity corresponding to its role as a contact zone of both early and recent human migrations in Asia. However, each single Orang Asli (indigenous) group was less diverse with a smaller effective population size (N(e)) than a European or an East Asian population, indicating a substantial isolation of some duration for these groups. All four MEGs were genetically more similar to Asian populations than to other continental groups, and the divergence time between MEGs and East Asian populations (12,000--6,000 years ago) was also much shorter than that between East Asians and Europeans. Thus, Malaysian Orang Asli groups, despite their significantly different features, may share a common origin with the other Asian groups. Nevertheless, we identified traces of recent gene flow from non-Asians to MEGs. Finally, natural selection signatures were detected in a batch of genes associated with immune response, human height, skin pigmentation, hair and facial morphology and blood pressure in MEGs. Notable examples include SYN3 which is associated with human height in all Orang Asli groups, a height-related gene (PNPT1) and two blood pressure-related genes (CDH13 and PAX5) in Negritos. We conclude that a long isolation period, subsequent gene flow and local adaptations have jointly shaped the genetic architectures of MEGs, and this study provides insight into the peopling and human migration history in Southeast Asia. PMID:24916469

  13. New expanded insulating materials prepared from recovered glass and nitrogenized admixtures

    Energy Technology Data Exchange (ETDEWEB)

    Rolland, A.; Verdier, P.; Guyader, J.; Laurent, Y.

    The paper presents the results of a study which has enabled the development of a light insulating material. This material is prepared by air heating a mixture of cullet (recovered broken glass) and a nitrogenized compound (nitrogenized kaolin or aluminium nitride). The expansion of the original material takes place at around 900C. After cooling down to 400C, the material is removed from the furnace. An examination is made of its density, its resistance to chemical agents, its temperature resistance, its thermal expansion coefficient, its resistance to thermal shocks, its compressive strength and its heat insulation coefficient. A comparative study is made between this material and Foamglass and Primeverre foam glass. The material developed is insulating, light, has closed porosity, is chemically inert and its load-bearing characteristics allow one to envisage its use in building materials or in more specialised applications.

  14. INFLUENCE OF MINERAL ADMIXTURES ON MECHANICAL PROPERTIES OF HIGH-PERFORMANCE CONCRETE

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The improvements of the me chanical properties, including bulk density of fresh mixtures, elastic modulus, and compressive strengths of four high-performance concrete mixtures, made with the addition of fly ash, refined ground blast-furnace microslag(microslag) and s ilica fume are studied.The concrete mixtures were determined based on the disper sion testing results.The study indicates that the elastic modulus at 28 and 91 days, an d compressive strengths of the concretes are improved a lot when fl y ash and microslag by 25 percent by weight of cement are added into the mixture s individually.The improvement is especially evident when silica fume by 5 perc e nt and fly ash by 25 percent by weight of cement are added together into the mix ture, while the fresh concrete mixture keeps a good workability.Through the anal ysis of chemically combined water ratios of the four mixtures at various hydrati on ages, it is found that the addition of all these mineral mixtures are benefic ial to the hydration process, especially, at later stages, which might be one of the reasons for the improvement of mechanical properties.

  15. Cooperative phenomena induced by Nb admixture in K1-xLixTaO3

    International Nuclear Information System (INIS)

    Raman scattering observations were performed on samples of K1-xLixTa1-yNbyO3, with x in the range 0.6-1.0 mol% and y in the range 0.2-0.3 mol%. Concentrations of Li and Nb, determined by analytical methods, were below the known thresholds at which these substituents can separately induce a ferroelectric transition in the quantum paraelectric KTaO3. The temperature evolution of TO1 and TO4 spectra was monitored. The results show a critical behaviour below 50 K, characterized by an abrupt increase of first-order scattering strengths and by spontaneous splitting of the non-softening TO1 mode. From our data, we infer the occurrence of a ferroelectric phase transition of order-disorder character. This proves that small additions of Nb enhance the tendency of the Li subsystem towards cooperative ordering in the KTaO3 matrix. (author)

  16. Exciton luminescence in krypton cryocrystals with an admixture of molecular deuterium

    International Nuclear Information System (INIS)

    The experimental data on VUV and UV cathodoluminescence spectra of Kr-based solid mixtures Kr-D2, Kr-D2-O2, and Kr-Xe-O2 for various dopant concentrations are presented. It is shown that introduction of a molecular deuterium impurity into krypton cryocrystals does not result in any new spectral features, suggesting that no excitation or dissociation of D2 takes place upon electron irradiation of the crystals. The intensity of the luminescence of matrix excitations is found to grow with D2 concentration. It is shown that the observed intensity growth is related to localization of matrix excitons in a limited crystal volume due to their quasi-elastic scattering by deuterium impurity molecules which results in a considerable decrease in mean free path and diffusion path length of the excitons, as well as their faster localization. Possible mechanisms of luminescence quenching in pure krypton cryocrystals are discussed. It is concluded that the quenching is due to annihilation of excitons in the process of their interactions with each other and with other electronic excitations of the crystal.

  17. New Polymeric Admixture for Cement Based on Hyperbranched Poly Amide-Ester with Pentaerythritol Core

    OpenAIRE

    Amal Amin Ibrahim; Ahmed El-Sayed Abdel-Megied; Mohamed Sayed Selim; Hassan Hassenen Darweesh; Magdy Mohamed Ayoub

    2013-01-01

    Hyperbranched poly amide-ester (HBPAE) was synthesized by a solution condensation polymerization through one-step process using pentaerythritol as a central core and AB2 prepolymerized monomer which was rapidly prepared at room temperature (25°C) using commercially available maleic anhydride (MA) and diethanolamine (DEA) monomers in the presence of p-toluene sulfonic acid as a catalyst. The prepared polymer was characterized by GPC, IR, 1H-NMR, and thermal analysis (TGA and DSC). The influenc...

  18. Spectral determination admixture of tin, antimony, lead, germanium by the method of fluoride sublimation

    International Nuclear Information System (INIS)

    In article introduced spectrographic investigation of selective treatment of Sn, Pb, Sb, Ge in form of their volatile fluoride, which are the product of decomposition of synthesized fluorine complex with iron

  19. Chemical Composition and Microstructure of Hydration Products of Hardened White Portland Cement Pastes Containing Admixtures

    Institute of Scientific and Technical Information of China (English)

    LI Qiu

    2015-01-01

    This study investigated the nature of hydration products of white portland cement (WPC) containing 20 mM malic acid or 1 M calcium chloride hydrated for 11 years. The study identiifed the hydration products and characterized the chemical composition, morphology, micro/nano structure of C-S-H and the main binding phase in cementitious materials. Calcium hydroxide (CH), ettringite and C-S-H were identiifed in WPC with 20 mM malic acid paste hydrated for 11 years. WPC with 1 M calcium chloride paste hydrated for 11 years contained the same phases, but with less CH, and the presence of Friedel’s salt (Ca2Al(OH)6Cl·2H2O). There were still small amount of anhydrous cement particles remaining in both pastes after 11 years hydration according to the SEM and29Si MAS NMR results. The hydration products of paste containing malic acid had a lower porosity than those prepared with calcium chloride upon visual inspection under SEM. The morphology of the outer product (Op) C-S-H was coarse ifbrillar and the inner product (Ip) C-S-H had a very ifne microstructure in both pastes under TEM. Both Ip and Op C-S-H formed in paste containing malic acid had lower Ca/Si and higher Al/Si than those in paste containing calcium chloride. C-S-H in paste containing calcium chloride had longer MCL and less percentage of bridging tetrahedra occupied by aluminum in silicon/aluminum chains due to relatively lessQ1 and moreQ2. A new type of silicon tetrahedra,Q2B, was introduced during deconvolution of29Si MAS NMR results. Ip and Op C-S-H in both pastes had aluminum substituted tobermorite-type and jennite-type structure, and all the charges caused by aluminum substituting silicon bridging tetrahedra were balanced by Ca2+.

  20. Characterization of the genetic diversity, structure and admixture of British chicken breeds.

    Science.gov (United States)

    Wilkinson, S; Wiener, P; Teverson, D; Haley, C S; Hocking, P M

    2012-10-01

    The characterization of livestock genetic diversity can inform breed conservation initiatives. The genetic diversity and genetic structure were assessed in 685 individual genotypes sampled from 24 British chicken breeds. A total of 239 alleles were found across 30 microsatellite loci with a mean number of 7.97 alleles per locus. The breeds were highly differentiated, with an average F(ST) of 0.25, similar to that of European chicken breeds. The genetic diversity in British chicken breeds was comparable to that found in European chicken breeds, with an average number of alleles per locus of 3.59, ranging from 2.00 in Spanish to 4.40 in Maran, and an average expected heterozygosity of 0.49, ranging from 0.20 in Spanish to 0.62 in Araucana. However, the majority of breeds were not in Hardy-Weinberg Equilibrium, as indicated by heterozygote deficiency in the majority of breeds (average F(IS) of 0.20), with an average observed heterozygote frequency of 0.39, ranging from 0.15 in Spanish to 0.49 in Cochin. Individual-based clustering analyses revealed that most individuals clustered to breed origin. However, genetic subdivisions occurred in several breeds, and this was predominantly associated with flock supplier and occasionally by morphological type. The deficit of heterozygotes was likely owing to a Wahlund effect caused by sampling from different flocks, implying structure within breeds. It is proposed that gene flow amongst flocks within breeds should be enhanced to maintain the current levels of genetic diversity. Additionally, certain breeds had low levels of both genetic diversity and uniqueness. Consideration is required for the conservation and preservation of these potentially vulnerable breeds. PMID:22497565

  1. Evidence for a bimodal distribution of hybrid indices in a hybrid zone with high admixture.

    Science.gov (United States)

    McKenzie, Jessica L; Dhillon, Rashpal S; Schulte, Patricia M

    2015-12-01

    The genetic structure of a hybrid zone can provide insights into the relative roles of the various factors that maintain the zone. Here, we use a multilocus approach to characterize a hybrid zone between two subspecies of killifish (Fundulus heteroclitus, Walbaum 1792) found along the Atlantic coast of North America. We first analysed clinal variation along the Atlantic coast using a single-nucleotide polymorphism in the mitochondrial DNA (mtDNA) displacement loop (D-loop) and a panel of nine nuclear microsatellite markers. A model constraining all clines to the same width and centre was not significantly different from a model in which the clines were allowed to vary independently. Locus-by-locus analysis indicated that the majority of nuclear clines shared the same centre as the mtDNA cline, and the widths of these clines were also narrower than that predicted by a neutral model, suggesting that selection is operating to maintain the hybrid zone. However, two of the nuclear clines had widths greater than the neutral prediction and had centres that were displaced relative to the mtDNA cline centre. We also found that a marsh located near the centre of the mtDNA cline demonstrated a bimodal distribution of nuclear hybrid index values, suggesting a deficit of first-generation hybrids and backcrossed genotypes. Thus, selection against hybrid genotypes may be playing a role in maintaining this hybrid zone and the associated steep nuclear and mtDNA clines. PMID:27019720

  2. Investigation of Mechanical Properties of Coconut Fiber as a Concrete Admixture

    Directory of Open Access Journals (Sweden)

    Ramli M.S.

    2014-01-01

    Full Text Available The high cost of conventional construction materials is the dominating factor affecting housing systems worldwide. Because of this, further research into alternative materials in construction is required. The purpose of this study is to experimentally investigate the physical characteristics and mechanical properties of concrete produced using shredded coconut fibre composites. The following percentage amounts of fibre were tested: 0 % (control, 0.6 %, and 1.8 %. The coconut fibres were cut to a certain length according to previous studies which suggested that the most ideal length is around 30 - 60mm. The test results showed that the compressive strength of concrete decreased as the percentage of total fibre in the concrete mix increased. The experimental results also showed that coconut fibre concrete performed satisfactorily in terms of crack growth in comparison to that of conventional concrete. Finally, it was concluded that the use of coconut fibres has great potential in the production of lightweight concrete or normal concrete for use in the construction of concrete structures. As coconut fibre is a natural material that is easily available and cheap, it is a particularly good, low-cost alternative. Therefore, this material has the potential to overcome the problem of escalating costs in the industry.

  3. Determination of chloride diffusion constants for concretes of differing water to cement ratios and admixtures

    OpenAIRE

    Smith, David Gilman

    1988-01-01

    Reinforced concrete exposed to chlorides is subject to rapid deterioration once the concentration of the chloride ion in the concrete reaches a critical level to cause corrosion of the reinforcing steel. The chloride ion diffuses through concrete according to Fick's Law, which is a function of time, a driving concentration, and a diffusion constant. The diffusion constant varies with temperature and the variety of concrete . The research included determination of diffusion ...

  4. Nested Hierarchical Dirichlet Processes for Multi-Level Non-Parametric Admixture Modeling

    OpenAIRE

    Tekumalla, Lavanya Sita; Agrawal, Priyanka; Bhattacharya, Indrajit

    2015-01-01

    Dirichlet Process(DP) is a Bayesian non-parametric prior for infinite mixture modeling, where the number of mixture components grows with the number of data items. The Hierarchical Dirichlet Process (HDP), is an extension of DP for grouped data, often used for non-parametric topic modeling, where each group is a mixture over shared mixture densities. The Nested Dirichlet Process (nDP), on the other hand, is an extension of the DP for learning group level distributions from data, simultaneousl...

  5. Influence of the mineral admixture on the durability of medium-strenght self compacting concrete

    OpenAIRE

    Bermejo Núñez, Ester B.; Gálvez Ruíz, Jaime; Fernández Cánovas, Manuel; Moragues Terrades, Amparo

    2010-01-01

    Self-compacting concrete (SCC) is an innovative concrete that does not require vibration for placing and compacting. SCC, developed in Japan in the 1980s, provides a present-day and attractive challenge for many researchers, as the long list of papers on the topic corroborates. Nevertheless, the durability of SCC, especially medium strength SCC, provides the researcher with opportunities for study in depth. This paper deals with the durability of SCC: two SCC mixtures, with 30 MPa com...

  6. STIMULATION OF PROCESS OF MUNERAL POWDER GRINDING THROUGH INTRODUCTION OF ADMIXTURES

    Directory of Open Access Journals (Sweden)

    Tarasov Roman Viktorovich

    2012-10-01

    Full Text Available The status of nanotechnologies in material science predetermines development of nanotechnology-intensive products that demonstrate pre-set properties of modified materials. The presence of nano-size particles of substances makes it possible to benefit from their physical and chemical potential and to overcome some negative developments that accompany the structure formation process (at interphase boundaries. The barrier properties are variable, which is quite important in terms of the increase of the asphalt concrete durability. Production of a modifier (that has nano-particles of the pre-set chemical composition to be added into asphalt concrete mixes is also of interest. The authors present their findings concerning the nano-scale modifier that has a chemically inert component and a hydraulically active substance. The method of de-aggregation is used to produce the nano-scale modifier. By-products are often welcomed as mineral components of the asphalt concrete, as they reduce its cost. The findings of the authors concerning the influence of the grinding mode on the integrated characteristics of the powder are presented in the paper. It is proven than dependence of integrated dispersion indicators is nonlinear due to processes leading to aggregation of mineral powder particles. The analysis of the experimental data collected in the course of "wet" grinding proves that surface-active substances stimulate the process of grinding. The type and concentration of an additive that improves the grinding efficiency is also identified.

  7. Admixture between historically isolated mitochondrial lineages in captive Western gorillas: recommendations for future management.

    Science.gov (United States)

    Soto-Calderón, Iván D; Dew, J Larry; Bergl, Richard A; Jensen-Seaman, Michael I; Anthony, Nicola M

    2015-01-01

    Although captive populations of western gorilla have been maintained in the United States for over a century, little is known about the geographic origins and genetic composition of the current zoo population. Furthermore, although previous mitochondrial analyses have shown that free-range gorilla populations exhibit substantial regional differentiation, nothing is known of the extent to which this variation has been preserved in captive populations. To address these questions, we combined 379 pedigree records with data from 52 mitochondrial sequences to infer individual haplogroup affiliations, geographical origin of wild founders and instances of inter-breeding between haplogroups in the United States captive gorilla population. We show that the current captive population contains all major mitochondrial lineages found within wild western lowland gorillas. Levels of haplotype diversity are also comparable to those found in wild populations. However, the majority of captive gorilla matings have occurred between individuals with different haplogroup affiliations. Although restricting crosses to individuals within the same haplogroup would preserve the phylogeographic structure present in the wild, careful management of captive populations is required to minimize the risk of drift and inbreeding. However, when captive animals are released back into the wild, we recommend that efforts should be made to preserve natural phylogeographic structure. PMID:25790828

  8. Extensive population admixture on drone congregation areas of the giant honeybee, Apis dorsata (Fabricius, 1793).

    Science.gov (United States)

    Beaurepaire, Alexis L; Kraus, Bernard F; Koeniger, Gudrun; Koeniger, Nikolaus; Lim, Herbert; Moritz, Robin F A

    2014-12-01

    The giant honeybee Apis dorsata often forms dense colony aggregations which can include up to 200 often closely related nests in the same location, setting the stage for inbred matings. Yet, like in all other Apis species, A. dorsata queens mate in mid-air on lek like drone congregation areas (DCAs) where large numbers of males gather in flight. We here report how the drone composition of A. dorsata DCAs facilitates outbreeding, taking into the account both spatial (three DCAs) and temporal (subsequent sampling days) dynamics. We compared the drones' genotypes at ten microsatellite DNA markers with those of the queen genotypes of six drone-producing colonies located close to the DCAs (Tenom, Sabah, Malaysia). None of 430 sampled drones originated from any of these nearby colonies. Moreover, we estimated that 141 unidentified colonies were contributing to the three DCAs. Most of these colonies were participating multiple times in the different locations and/or during the consecutive days of sampling. The drones sampled in the DCAs could be attributed to six subpopulations. These were all admixed in all DCA samples, increasing the effective population size an order of magnitude and preventing matings between potentially related queens and drones. PMID:25558361

  9. Extensive population admixture on drone congregation areas of the giant honeybee, Apis dorsata (Fabricius, 1793)

    OpenAIRE

    Beaurepaire, Alexis L; Kraus, Bernard F; Koeniger, Gudrun; KOENIGER, Nikolaus; Lim, Herbert; Moritz, Robin F.A.

    2014-01-01

    The giant honeybee Apis dorsata often forms dense colony aggregations which can include up to 200 often closely related nests in the same location, setting the stage for inbred matings. Yet, like in all other Apis species, A. dorsata queens mate in mid-air on lek like drone congregation areas (DCAs) where large numbers of males gather in flight. We here report how the drone composition of A. dorsata DCAs facilitates outbreeding, taking into the account both spatial (three DCAs) and temporal (...

  10. Race, Interracial Admixture and Genetic Differentiation of Avocado (Persea americana Mill)

    Science.gov (United States)

    Avocado (Persea americana Mill.) is a major tropical fruit crop native to Mesoamerica and domesticated around 8000 to 7000 BC. It is a member of the Laureace family and currently classified into three subspecies or races: Guatemalan (G), Mexican (M) and West Indian (WI) according to their ecological...

  11. Biogeographic ancestry, self-identified race, and admixture-phenotype associations in the Heart SCORE Study.

    Science.gov (United States)

    Halder, Indrani; Kip, Kevin E; Mulukutla, Suresh R; Aiyer, Aryan N; Marroquin, Oscar C; Huggins, Gordon S; Reis, Steven E

    2012-07-15

    Large epidemiologic studies examining differences in cardiovascular disease (CVD) risk factor profiles between European Americans and African Americans have exclusively used self-identified race (SIR) to classify individuals. Recent genetic epidemiology studies of some CVD risk factors have suggested that biogeographic ancestry (BGA) may be a better predictor of CVD risk than SIR. This hypothesis was investigated in 464 African Americans and 771 European Americans enrolled in the Heart Strategies Concentrating on Risk Evaluation (Heart SCORE) Study in March and April 2010. Individual West African and European BGA were ascertained by means of a panel of 1,595 genetic ancestry informative markers. Individual BGA varied significantly among African Americans and to a lesser extent among European Americans. In the total cohort, BGA was not found to be a better predictor of CVD risk factors than SIR. Both measures predicted differences in the presence of the metabolic syndrome, waist circumference, triglycerides, body mass index, very low density lipoprotein cholesterol, lipoprotein A, and systolic and diastolic blood pressure between European Americans and African Americans. These results suggest that for most nongenetic cardiovascular epidemiology studies, SIR is sufficient for predicting CVD risk factor differences between European Americans and African Americans. However, higher body mass index and diastolic blood pressure were significantly associated with West African BGA among African Americans, suggesting that BGA should be considered in genetic cardiovascular epidemiology studies carried out among African Americans. PMID:22771727

  12. InP layers with low density of defects: effect of holmium and erbium admixture

    Czech Academy of Sciences Publication Activity Database

    Procházková, Olga; Novotný, Jan; Zavadil, Jiří; Kohout, Jindřich; Žďánský, Karel

    1997-01-01

    Roč. 48, 9 Special Issue (1997), s. 66-69. ISSN 0013-578X. [Development of Materials Science in Research and Education - DMS-RE 1997 /7./. Kočovce, 09.06.1997-11.06.1997] R&D Projects: GA ČR GA102/96/1238 Keywords : semiconductors * epitaxial growth * rare earth compounds * crystal defects Subject RIV: CA - Inorganic Chemistry

  13. Sequencing of diverse mandarin, pummelo and orange genomes reveals complex history of admixture during citrus domestication

    Science.gov (United States)

    Cultivated citrus are selections from, or hybrids of, wild progenitor species whose identities and contributions to citrus domestication remain controversial. Here we sequence and compare citrus genomes—a high-quality reference haploid clementine genome and mandarin, pummelo, sweet-orange and sour-o...

  14. Search for the admixture of heavy neutrinos in the recoil spectra of 37Ar decay

    International Nuclear Information System (INIS)

    Neutrino-induced recoil spectra of 37Cl ions produced in the electron capture (EC) decay of 37Ar were measured and searched for the presence of massive neutrinos admixed to the dominant electron neutrino. Fractions of a monolayer of 37Ar were physisorbed on Au and on several underlayers of 40Ar adsorbed on both Au and graphite substrates cooled to ≤20 K under ultrahigh vacuum conditions. Time-of-flight spectra of the recoiling ions were recorded in coincidence with x rays and Auger electrons emitted following the EC decay. By searching these spectra for peaks with energies between 7.6 eV and 3.6 eV upper limits were placed on the mixing probability of the electron neutrino with heavy neutrinos in the 370 - 640 keV mass range. These limits vary from 1 to 4%, at the 90% confidence level. copyright 1998 The American Physical Society

  15. Use of waste plastics and rubber as admixtures into coking charges

    Czech Academy of Sciences Publication Activity Database

    Straka, Pavel

    Pittsburgh: University of Pittsburgh, 2004 - (Morsi, B.), 48-5/1-48-5/7 [Annual International Pittsburgh Coal Conference - Coal - Energy and Environment /21./. Osaka (JP), 13.09.2004-17.09.2004] R&D Projects: GA AV ČR(CZ) IBS3046004 Institutional research plan: CEZ:AV0Z3046908 Keywords : coal * waste plastics * rubber Subject RIV: DH - Mining, incl. Coal Mining www.engr.pitt.edu/pcc

  16. Investigation of Mechanical Properties of Coconut Fiber as a Concrete Admixture

    OpenAIRE

    Ramli M.S.; Abas N.F.; Othuman Mydin M.A.

    2014-01-01

    The high cost of conventional construction materials is the dominating factor affecting housing systems worldwide. Because of this, further research into alternative materials in construction is required. The purpose of this study is to experimentally investigate the physical characteristics and mechanical properties of concrete produced using shredded coconut fibre composites. The following percentage amounts of fibre were tested: 0 % (control), 0.6 %, and 1.8 %. The coconut fibres were cut ...

  17. Influence of The Activated Qatari Attapulgite Clay Admixture on The Mechanical Properties and Hydration Kinetics of Ordinary Portland Cement

    OpenAIRE

    Al-Noaimi, Kawkab Kh. [كوكب النعيمي

    2001-01-01

    Blended cements are types of cements containing additives other than those used m Portland cement, which have considerable technological interest, because such addition increases the chemical resistance to sulfate and chloride attack. The present investigation represents a laboratory study, which provides a unique opportunity to introduce an effective practical attempt to deal with the problem of concrete deterioration m Qatar and the Arabian Gulf region, and to provide a solution to the prob...

  18. Wild Trypanosoma cruzi I genetic diversity in Brazil suggests admixture and disturbance in parasite populations from the Atlantic Forest region

    OpenAIRE

    Lima, VS; Jansen, AM; Messenger, LA; Miles, MA; Llewellyn, MS

    2014-01-01

    BACKGROUND Trypanosoma cruzi (Kinetoplastida, Trypanosomatidae) infection is an ancient and widespread zoonosis distributed throughout the Americas. Ecologically, Brazil comprises several distinct biomes: Amazonia, Cerrado, Caatinga, Pantanal and the Atlantic Forest. Sylvatic T. cruzi transmission is known to occur throughout these biomes, with multiple hosts and vectors involved. Parasite species-level genetic diversity can be a useful marker for ecosystem health. Our aims were to: investiga...

  19. Unexpected patterns of admixture in German populations of Aedes Japonicus Japonicus (Diptera: Culicidae) underscore the importance of human intervention

    OpenAIRE

    Zielke, Dorothee E; Werner, Doreen; Schaffner, Francis; Kampen, Helge; Dina M Fonseca

    2014-01-01

    The mosquito Aedes japonicus japonicus, originally restricted to temperate East Asia, is now widespread in North America and more recently has become established in Europe. To ascertain the putative number of separate introductions to Europe and examine patterns of expansion we analyzed the genetic makeup of Ae. j. japonicus populations from five cemeteries in North Rhine-Westphalia and Rhineland-Palatinate, two western German federal states, as well as of specimens from populations in Belgiu...

  20. Unexpected Patterns of Admixture in German Populations of Aedes japonicus japonicus (Diptera: Culicidae) Underscore the Importance of Human Intervention

    OpenAIRE

    Zielke, Dorothee E; Doreen Werner; Francis Schaffner; Helge Kampen; Dina M Fonseca

    2014-01-01

    The mosquito Aedes japonicus japonicus, originally restricted to temperate East Asia, is now widespread in North America and more recently has become established in Europe. To ascertain the putative number of separate introductions to Europe and examine patterns of expansion we analyzed the genetic makeup of Ae. j. japonicus populations from five cemeteries in North Rhine-Westphalia and Rhineland-Palatinate, two western German federal states, as well as of specimens from populations in Belgiu...

  1. CO2 reaction with hydrated class H well cement under geologic sequestration conditions: effects of flyash admixtures.

    Science.gov (United States)

    Kutchko, Barbara G; Strazisar, Brian R; Huerta, Nicolas; Lowry, Gregory V; Dzombak, David A; Thaulow, Niels

    2009-05-15

    The rate and mechanism of reaction of pozzolan-amended Class H cement exposed to both supercritical CO2 and CO2-saturated brine were determined under geologic sequestration conditions to assess the potential impact of cement degradation in existing, wells on CO2 storage integrity. The pozzolan additive chosen, Type F flyash, is the most common additive used in cements for well sealing in oil-gas field operations. The 35:65 and 65:35 (v/v) pozzolan-cement blends were exposed to supercritical CO2 and CO2-saturated brine and underwent cement carbonation. Extrapolation of the carbonation rate for the 35:65 case suggests a penetration depth of 170-180 mm for both the CO2-saturated brine and supercritical CO2 after 30 years. Despite alteration in both pozzolan systems, the reacted cement remained relatively impermeable to fluid flow after exposure to brine solution saturated with CO2, with values well below the American Petroleum Institute recommended maximum well cement permeability of 200 microD. Analyses of 50: 50 pozzolan-cement cores from a production well in a sandstone reservoir exhibited carbonation and low permeability to brine solution saturated with CO2, which are consistent with our laboratory findings. PMID:19544912

  2. Synthesis of PbI.sub.2./sub. with admixture of rare earth elements: electrical and optical properties

    Czech Academy of Sciences Publication Activity Database

    Matuchová, Marie; Žďánský, Karel; Zavadil, Jiří

    Cádiz: Universidad de Cádiz, 2006 - (Sales, D.). 110-- [EXMATEC 2006 - International Workshop on Expert Evaluation & Control of Compound Semiconductor Materials & Technologies /8./. 14.05.2006-17.05.2006, Cádiz] R&D Projects: GA ČR GA102/04/0959; GA AV ČR KSK1010104 Institutional research plan: CEZ:AV0Z20670512 Keywords : characteristics measurement * doping * X-ray diffraction Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  3. Synthesis of PbI.sub.2./sub. with admixture of rare earth elements: electrical and optical properties

    Czech Academy of Sciences Publication Activity Database

    Matuchová, Marie; Žďánský, Karel; Zavadil, Jiří

    2007-01-01

    Roč. 4, č. 4 (2007), s. 1532-1535. ISSN 1610-1634. [EXMATEC 2006 - International Workshop on Expert Evaluation & Control of Compound Semiconductor Materials & Technologies /8./. Cádiz, 14.05.2006-17.05.2006] R&D Projects: GA ČR GA102/04/0959; GA AV ČR KSK1010104 Institutional research plan: CEZ:AV0Z20670512 Keywords : characteristics measurement * doping * X-ray diffraction Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  4. Understanding geographic origins and history of admixture among chimpanzees in European zoos, with implications for future breeding programmes

    DEFF Research Database (Denmark)

    Hvilsom, Christina; Frandsen, Peter; Børsting, Claus;

    2013-01-01

    the range of the species in Africa, and 20% of the European zoo population. We applied the knowledge about subspecies differentiation throughout equatorial Africa to assign origin to chimpanzees in the largest conservation management programme globally. A total of 63% of the genotyped chimpanzees from...... the European zoos could be assigned to one of the recognized subspecies. The majority being of West African origin (40%) will help consolidate the current breeding programme for this subspecies and the identification of individuals belonging to the two other subspecies so far found in European zoos...... can form the basis for breeding programmes for these. Individuals of various degree of mixed ancestry made up 37% of the genotyped European zoo population and thus highlight the need for appropriate management programmes guided by genetic analysis to preserve maximum genetic diversity and reduce...

  5. Analysis Technique on Water Permeability in Concrete with Cold Joint considering Micro Pore Structure and Mineral Admixture

    Directory of Open Access Journals (Sweden)

    Se-Jin Choi

    2015-01-01

    Full Text Available Cold joint in concrete due to delayed concrete placing may cause a reduced shear resistance and increased water permeation. This study presents an analytical model based on the concept of REV (Representative Element Volume to assess the effect of water permeability in cold joint concrete. Here, OPC (Ordinary Portland Cement concrete samples with cold joint are prepared and WPT (Water Permeability Test is performed on the samples cured for 91 days. In order to account for the effect of GGBFS (Granulated Ground Blast Furnace Slag on water permeability, concrete samples with the same W/B (Water to Binder ratio and 40% replacement ratio of GGBFS are tested as well. Utilizing the previous models handling porosity and saturation, the analysis technique for equivalent water permeability with effective cold joint width is proposed. Water permeability in cold joint increases to 140.7% in control case but it decreases to 120.7% through GGBFS replacement. Simulation results agree reasonably well with experimental data gathered for sound and cold joint concrete.

  6. Genetic divergence between Atlantic and Indo-Pacific stocks of bigeye tuna (Thunnus obesus) and admixture around South Africa.

    Science.gov (United States)

    Chow, S; Okamoto, H; Miyabe, N; Hiramatsu, K; Barut, N

    2000-02-01

    Two mitochondrial DNA segments of the bigeye tuna (Thunnus obesus) were amplified by polymerase chain reaction (PCR), and restriction fragment length polymorphism (RFLP) analyses of these segments were used for the genetic stock study. The variation in a segment flanking the ATPase and COIII genes was low; only two genotypes (alpha and beta) were detected by RsaI digestion. Yet a large difference in the genotype distribution was observed between ocean basin samples. The alpha type predominated in four Atlantic samples, where 178 of 244 individuals were the alpha type. In contrast, only one of 195 individuals collected in the Indo-Pacific was the alpha type? The frequency of the alpha type varied considerably from 0 to 80% among seven samples collected off the Cape of Good Hope. The variation found in the other segment, containing the D-loop region, was much higher; two endonucleases (DpnII and RsaI) detected five genotypes each and 15 composite genotypes. A highly significant difference in genotype frequencies was observed between the Atlantic and Indo-Pacific samples, but no heterogeneity was observed among the four Atlantic or among four Indo-Pacific samples. These results clearly indicate that not only gene flow, but also fish migration, between the Atlantic and Indian Oceans are severely restricted, and that fishes from these distinct stocks are intermingling around South Africa. The simple and diagnostic genetic marker found in this study can be used to estimate mixing ratios between Atlantic and Indian stocks around South Africa. PMID:10672166

  7. Strong genetic admixture in the Altai at the Middle Bronze Age revealed by uniparental and ancestry informative markers.

    Science.gov (United States)

    Hollard, Clémence; Keyser, Christine; Giscard, Pierre-Henri; Tsagaan, Turbat; Bayarkhuu, Noost; Bemmann, Jan; Crubézy, Eric; Ludes, Bertrand

    2014-09-01

    The Altai Mountains have been a long-term boundary zone between the Eurasian Steppe populations and South and East Asian populations. To disentangle some of the historical population movements in this area, 14 ancient human specimens excavated in the westernmost part of the Mongolian Altai were studied. Thirteen of them were dated from the Middle to the End of the Bronze Age and one of them to the Eneolithic period. The environmental conditions encountered in this region led to the good preservation of DNA in the human remains. Therefore, a multi-markers approach was adopted for the genetic analysis of identity, ancestry and phenotype markers. Mitochondrial DNA analyses revealed that the ancient Altaians studied carried both Western (H, U, T) and Eastern (A, C, D) Eurasian lineages. In the same way, the patrilineal gene pool revealed the presence of different haplogroups (Q1a2a1-L54, R1a1a1b2-Z93 and C), probably marking different origins for the male paternal lineages. To go further in the search of the origin of these ancient specimens, phenotypical characters (i.e. hair and eye color) were determined. For this purpose, we adapted the HIrisPlex assay recently described to MALDI-TOF mass spectrometry. In addition, some ancestry informative markers were analyzed with this assay. The results revealed mixed phenotypes among this group confirming the probable admixed ancestry of the studied Altaian population at the Middle Bronze Age. The good results obtained from ancient DNA samples suggest that this approach might be relevant for forensic casework too. PMID:25016250

  8. High level of male-biased Scandinavian admixture in Greenlandic Inuit shown by Y-chromosomal analysis

    DEFF Research Database (Denmark)

    Bosch, Elena; Calafell, Francesc; Rosser, Zoë H; Nørby, Søren; Lynnerup, Niels; Hurles, Matthew E; Jobling, Mark A

    2003-01-01

    We have used binary markers and microsatellites on the Y chromosome to analyse diversity in a sample of Greenlandic Inuit males. This sample contains Y chromosomes typical of those found in European populations. Because the Y chromosome has a unique and robust phylogeny of a time depth that prece...

  9. Corona discharge experiments in admixtures of N2 and CH4: a laboratory simulation of Titan's atmosphere

    OpenAIRE

    Horvath, G.; Skalny, J. D.; Mason, N.J.; Klas, M.; Zahoran, M.; Vladoiu, R.; Manole, M.

    2009-01-01

    A positive corona discharge fed by a N2:CH4 mixture (98:2) at atmospheric pressure and ambient temperature has been studied as a laboratory mimic of the chemical processes occurring in the atmosphere of Titan, Saturn's largest moon. In-situ measurements of UV and IR transmission spectra within the discharge have shown that the main chemical product is C2H2, produced by dissociation of CH4, with small but significant traces of ethane and HCN, all species that have been detected in Titan's atmo...

  10. Admixture analysis of stocked brown trout populations using mapped microsatellite DNA markers: indigenous trout persist in introgressed populations

    DEFF Research Database (Denmark)

    Hansen, Michael Møller; Mensberg, Karen-Lise Dons

    2009-01-01

    , but resolution is low if genetic differentiation is weak. Here, we analyse stocked brown trout populations represented by historical (1943-1956) and contemporary (2000s) samples, where genetic differentiation between wild populations and stocked trout is weak (pair-wise F-ST of 0.047 and 0.053). By...

  11. Winning the invasion roulette: escapes from fish farms increase admixture and facilitate establishment of non-native rainbow trout

    OpenAIRE

    Consuegra, Sofia; Phillips, Nia; Gajardo, Gonzalo; de Leaniz, Carlos Garcia

    2011-01-01

    Aquaculture is a major source of invasive aquatic species, despite the fact that cultured organisms often have low genetic diversity and tend to be maladapted to survive in the wild. Yet, to what extent aquaculture escapees become established by means of high propagule pressure and multiple origins is not clear. We analysed the genetic diversity of 15 established populations and four farmed stocks of non-native rainbow trout in Chile, a species first introduced for recreational fishing around...

  12. Higher genetic diversity in recolonized areas than in refugia of Alnus glutinosa triggered by continent-wide lineage admixture

    Czech Academy of Sciences Publication Activity Database

    Havrdová, Alena; Douda, Jan; Krak, Karol; Vít, Petr; Hadincová, Věroslava; Zákravský, Petr; Mandák, Bohumil

    2015-01-01

    Roč. 24, č. 18 (2015), s. 4759-4777. ISSN 0962-1083 R&D Projects: GA ČR(CZ) GAP504/11/0402 Institutional support: RVO:67985939 Keywords : Approximate Bayesian computation * black alder * climate change * phylogeography * temperate tree Subject RIV: EF - Botanics Impact factor: 6.494, year: 2014

  13. 活性掺合料再生混凝土抗冻性能试验%Experiment on the frost resistance of active admixture recycled concrete

    Institute of Scientific and Technical Information of China (English)

    陈爱玖; 孙晓培; 张敏; 王静

    2014-01-01

    The concrete engineering is worst affected by frost damage in north area of China.analysis of five factors (slag powder,fly ash,air-entraining agent,polypropylene fiber and recycled coarse aggregate) on the influence law of recycled concrete frost resistance by orthogonal test.Find out the most important influence factors on relative loss modulus and compressive strength of recycled concrete ,by compare the recycled concrete freeze-thaw cycle 0 times and 200 times,loss modulus and compressive strength,then analysis of the mech-anism of recycled concrete.%我国北方地区的混凝土工程是受冻害最严重的地区。采用正交试验法分析矿渣粉、粉煤灰、引气剂、聚丙烯纤维和再生粗骨料对再生混凝土抗冻性的影响规律,即:对比再生混凝土冻融循环次数0、200次的质量损失、相对动弹模量、抗压强度,找出对再生混凝土的相对动弹模量和抗压强度影响最大的因素,并对影响机理进行分析。

  14. Genetic admixture, social-behavioral factors, and body composition are associated with blood pressure differently by racial-ethnic group among children.

    OpenAIRE

    Klimentidis, Yann C.; Dulin-Keita, Akilah; Casazza, Krista; Willig, Amanda L.; Allison, David B.; Fernandez, Jose R.

    2011-01-01

    Cardiovascular disease has a progressively earlier age of onset, and disproportionately affects African Americans in the US. It has been difficult to establish the extent to which group differences are due to physiological, genetic, social, or behavioral factors. In this study, we examined the association between blood pressure and these factors among a sample of 294 children, identified as African-, European-, or Hispanic-American. We use body composition, behavioral (diet and physical activ...

  15. Formulación de mezclas intratecales para el tratamiento del dolor Compounding of drug admixtures for intrathecal treatment of pain

    OpenAIRE

    M. P. Ortega-García; A. Mínguez-Martí; M. D. López Alarcón; J. de Andrés-Ibáñez; GARCÍA-LÓPEZ, M.

    2012-01-01

    Las mezclas de fármacos en analgesia intratecal están recomendadas en documentos de consenso internacionales, sin embargo pocos datos existen sobre su estabilidad y seguridad. El objetivo de esta revisión es evaluar los requerimientos específicos a tener en cuenta en la preparación de mezclas intratecales y revisar los estudios de estabilidad publicados de las mezclas de fármacos recomendadas en terapia analgésica. Las mezclas intratecales tienen unas particularidades especiales a la hora de ...

  16. Fluid Mechanics Prize-Otto Laporte Lecture: The Art of Mixing with an Admixture of Art: Fluids, Solids, and Visual Imagination

    Science.gov (United States)

    Ottino, Julio Mario

    2008-11-01

    Arguably, fluid dynamics is intimately linked with visual imagination more than any other branch of physical sciences. A particular example is mixing. Fluid mixing, and under more limited circumstances, granular mixing, can be placed in the framework of dynamical systems and a geometric viewpoint. On the fluid mixing side, the physical connection can be traced back to the stretching and folding of fluid elements and possibility of representation motions in terms of transformations. This opens a wealth of possibilities --- the mathematical machinery of dynamical systems on the theory side, and the possibility of inventing devices on the practical side. There are notable differences as well: granular materials un-mix or segregate, often spectacularly so, and some aspects of segregation can also be incorporated in the mathematical framework. A technical review will highlight key points in both areas -- experiments, applications, and the many branches that have taken root since the mid-1980s. However, much of this could have taken place sooner. The basic mechanisms and key experimental results in both areas were identified early: the stretching and folding mechanism of mixing was pointed out by Osborne Reynolds in 1893-1895, and a key segregation mechanism of granular mixtures was noted by Yositisi Oyama in 1939. In what may appear surprising on a first viewing, these leads were not followed. Ideas, in order to be embraced, need to fit with the canonical knowledge of the times.

  17. Improvement of scintillation properties in Lu.sub.3./sub.Al.sub.5./sub.O.sub.12./sub.-based single crystal scintillators by Ga admixture

    Czech Academy of Sciences Publication Activity Database

    Ogino, H.; Yoshikawa, A.; Nikl, Martin; Mihóková, Eva; Vedda, A.; Shimoyama, J.-i.; Kishio, K.

    Pisa : Plus - Pisa University Press, 2009 - (Tonelli, M.; Di Lieto, A.). s. 95-95 ISBN 978-88-8492-638-8. [International Symposium on Laser, Scintillator and Non Linear Optical Materials /5./. 03.09.2009-05.09.2009, Pisa] Institutional research plan: CEZ:AV0Z10100521 Keywords : LuAG scintillator * substitution of Al by Ga * thermoluminescence * light yield Subject RIV: BM - Solid Matter Physics ; Magnetism

  18. Modified cupric reducing antioxidant capacity (CUPRAC) assay for measuring the antioxidant capacities of thiol-containing proteins in admixture with polyphenols.

    Science.gov (United States)

    Cekiç, Sema Demirci; Başkan, Kevser Sözgen; Tütem, Esma; Apak, Reşat

    2009-07-15

    Proteins are not considered as true antioxidants but are known to protect antioxidants from oxidation in various antioxidant activity assays. This study aims to investigate the contribution of proteins, especially thiol-containing proteins, to the observed overall antioxidant capacity measured by known methods. To determine the antioxidant properties of thiol-containing proteins, the CUPRAC method of antioxidant assay using the oxidizing reagent Cu(II)-neocuproine previously used for simultaneous analysis of cystine and cysteine was adopted. While the CUPRAC method is capable of determining all antioxidant compounds including thiols in complex sample matrices, the Ellman method of thiol quantitation basically does not respond to other antioxidants. The antioxidant quantities in the selected samples were assayed with the ABTS and FRAP methods as well as with the CUPRAC method. In all applied methods, the dilutions were made with a standard pH 8 buffer used in the Ellman method by substituting the Na(2)EDTA component of the buffer with sodium citrate. On the other hand, the standard CUPRAC protocol was modified by substituting the pH 7 ammonium acetate buffer (at 1M concentration) with 8M urea buffer adjusted to pH 7 by neutralizing with 6M HCl. Urea helps to partly solubilize and denaturate proteins so that their buried thiols be oxidized more easily. All methods used in the estimation of antioxidant properties of proteins (i.e., CUPRAC, Ellman, ABTS, and FRAP) were first standardized with a simple thiol compound, cysteine, by constructing the calibration curves. The molar absorptivities of these methods for cysteine were: epsilon(CUPRAC)=7.71x10(3), epsilon(Ellman)=1.37x10(4), epsilon(ABTS)=2.06x10(4), and epsilon(FRAP)=2.98x10(3)L mol(-1)cm(-1). Then these methods were applied to various samples containing thiols, such as glutathione (reduced form:GSH), egg white, whey proteins, and gelatin. Additionally, known quantities of selected antioxidants were added to these samples to show the additivity of responses. PMID:19559889

  19. New-generation Polycarboxylate Admixture Technology and Applications%新一代聚羧酸盐外加剂技术及其应用

    Institute of Scientific and Technical Information of China (English)

    郭景强; 齐广华

    2010-01-01

    西卡ViscoCrete新一代聚羧酸盐外加剂属第三代高性能外加剂,是生产高强混凝土的重要原材料.本文主要介绍聚羧酸外加剂的发展及在高强自密实混凝土、耐久性混凝土、清水混凝土、预应力预制梁、高层泵送及长距离泵送混凝土等不同混凝土领域的工程应用情况.

  20. 保坍型聚羧酸减水剂的吸附-分散机理%Adsorption-dispersion mechanism of polycarboxylate admixture for slump retention (PCA)

    Institute of Scientific and Technical Information of China (English)

    赵越; 蒋亚清; 张敏杰

    2016-01-01

    分析了保坍型聚羧酸减水剂(PCA)的等温吸附特性,利用XRD研究了PCA在C3A水化产物中的插层行为,基于TGDSC定量了掺与不掺减水剂的水泥浆体中的钙矾石(AFt)和单硫型水化硫铝酸钙(AFm).结果表明,PCA可在水化铝酸钙中插层,形成的有机金属矿物相在水泥水化体系中逐步转化为AFm,加之PCA促进了水泥水化初期AFt和AFm形成,使1h吸附量降低.促进水化硫铝酸钙形成及提高溶液经时平衡浓度是保坍型聚羧酸减水剂的主要作用机制.

  1. RHEOPLUS:新改良聚羧酸醚类外加剂%RHEOPLUS:A new modified polycarboxylate-based admixture

    Institute of Scientific and Technical Information of China (English)

    杨健英; Sven M.F.Asmus

    2004-01-01

    新一代聚羧酸醚类(PCE)减水剂RHEOPLUS已成功开发.研究发现,REOPLUS与多种水泥兼容性良好,主要表现在掺量的高效性和良好的坍落度保持能力.其卓越的性能也同样体现在高流动混凝土的应用中,即良好的泵送性、和易性、抗离析和坍落度/流动度保持能力等.此外,RHEOPLUS对早期强度的改善也为其在预制构件中的应用带来了优势.相关研究正在进行,并已取得了一些阶段性成果.

  2. 聚羧酸系外加剂与水泥的适应性研究%Study on Compatibility Between Polycarboxylic Admixtures and Cement

    Institute of Scientific and Technical Information of China (English)

    于涛

    2011-01-01

    本文针对混凝土中聚羧酸系外加剂与水泥的适应性进行系统的试验,研究了水泥中碱含量、水泥的细度和掺量对聚羧酸系外加剂适应性的影响.通过混凝土配合比的设计及试验,确定水泥对聚羧酸系外加剂适应性的影响规律,并通过试验指导实际生产,保证混凝土的各项性能满足施工及技术要求.试验结果表明,在本实验范围内,随着水泥中碱含量的增加和水泥细度的增加,混凝土拌和物的坍落度损失也随之增大,满足工作性时聚羧酸系外加剂的掺量也需相应增大;混凝土早期抗压强度随水泥中碱含量的增加而略有增大,但后期28d抗压强度变化不明显;水泥中碱含量一定时,随着水泥用量的增加,混凝土中总碱量也相应增加,但对聚羧酸系外加剂的适应性并未产生明显的影响.

  3. Influence regularities of chemical admixtures on creep%化学外加剂对混凝土徐变的影响规律研究

    Institute of Scientific and Technical Information of China (English)

    张异; 钱春香; 赵飞; 何智海; 曲军; 郭景强; Michael Danzinger

    2013-01-01

    The influence law of naphthalene based plasticizer,polycarboxylic superplasticizer,retarding component and shrinkage reducing component on creep characteristics of concrete with same mix proportion were studied by the self-made creep loading device and the influence mechamism were analyzed by testing non-evaporable water of paste with same water-binder ratio with concrete and internal relative humidity of loaded concrete specimens.The results indicate that:compared with naphthalene based plasticizer,polycarboxylic superplasticizers could significantly reducing creep of concrete,and this effect of early-strength polycarboxylic superplasticizer is the best; shrinkage reducing components could also reduce creep,the incorporation of retarding component have an adverse effect on creep; polycarboxylic superplasticizers and shrinkage reducing component reduce creep by decreasing the internal moisture transmission and diffusion to external environment; early-strength polycarboxylic superplasticizer make concrete have more hydration products,which have certain advantages on increasing strength and lower creep; incorporation of retarding component slows hydration and reduce the total hydration product contents,therefore strength reduced and creep increased.%采用自制的徐变加载装置,研究了萘系减水剂、聚羧酸减水剂以缓凝组分、减缩组分对等配合比混凝土徐变的影响规律,结合与混凝土同水灰比浆体非可蒸发水含量及混凝土内部相对湿度演化分析了其影响机理.结果表明,相比萘系减水剂,聚羧酸减水剂能显著降低混凝土的徐变,其中以早强型聚羧酸减水剂的效果最好;减缩剂对混凝土的徐变有降低作用,缓凝组分的掺入对徐变有不利影响;聚羧酸减水剂和减缩组分能通过降低混凝土内部水分传输和向外界扩散来降低徐变;早强型聚羧酸使浆体具有较多的水化产物数量,对强度的增加和徐变的降低有一定好处,缓凝组分的掺入会延缓水化并减少总水化产物数量,降低强度,使徐变增加.

  4. The Application of Polycarboxylates Admixture in Pre-Mixed Concrete%聚羧酸系外加剂在预拌混凝土中的应用

    Institute of Scientific and Technical Information of China (English)

    齐广华

    2006-01-01

    聚羧酸系外加剂在高强高性能混凝土中的应用已被业界人士所熟知,但是在预拌混凝土企业中,在全部等级的混凝土中的应用,在国内目前只此一家.瑞科尔建筑材料(天津)有限公司在试验和生产过程中很好的解决了聚羧酸系外加剂在普通混凝土尤其是在低强度、低坍落度混凝土中应用存在的技术和经济方面的问题.本文介绍了聚羧酸类外加剂对水泥适应性及混凝土性能的影响并对聚羧酸系外加剂的减水机理和在混凝土中所体现出的优势,以及存在的问题进行了详细的论述.

  5. 新型聚羧酸系保坍剂的合成与性能研究%Research on Synthesis and Performance of Polycarboxylic Slump Retaining Admixture

    Institute of Scientific and Technical Information of China (English)

    廖国胜; 何正恋; 刘佩

    2013-01-01

    根据减水剂的“吸附-分散”作用机理,通过一步法使改性聚醚与不饱和羧酸共聚,在引入阴离子表面活性基团的条件下,制备出一种具有羧基、羟基、磺酸基等阴离子活性基团的高性能聚羧酸保坍剂.通过对掺加该聚羧酸保坍剂进行水泥净浆流动度试验、水泥适应性试验、混凝土应用性能试验以及对其进行红外光谱分析,测试聚羧酸保坍剂的性能.

  6. Experimental researches on the compatibility of polycarboxylic admixtures with cements%聚羧酸外加剂与水泥适应性试验研究

    Institute of Scientific and Technical Information of China (English)

    安同富; 刘建江; 王永芳; 李岩; 史红玉

    2006-01-01

    本文选择目前市场上3种较具代表性的聚羧酸外加剂,针对12个不同厂家品种的水泥样品,进行水泥净浆流动度和有关混凝土性能试验,比较聚羧酸外加剂与不同水泥的相容性;同时,在水泥不同熟化时间和不同温度状态条件下,对掺用聚羧酸外加剂的水泥净浆和混凝土性能变化进行了试验研究.根据试验结果,聚羧酸外加剂在拌制水泥浆尤其是混凝土的性能表现,受所用水泥品质和使用时水泥的温度影响.

  7. 新型聚羧酸系保塑剂的性能研究%Study on performance of neotype polycarboxylate-plastic retaining admixture

    Institute of Scientific and Technical Information of China (English)

    龚英; 段国荣; 黄国泓

    2010-01-01

    针对混凝土坍落度损失较快问题,研制了一种梯形结构聚羧酸系保塑剂,对该保塑剂的性能研究结果表明,在低掺量时具有高坍落度保持能力,其混凝土工作性好,与水泥适应性良好,与减水剂复配后效果明显优于单掺.掺入保塑剂后,可明显减缓水泥早期水化放热速率,有利于提高混凝土的抗裂性.

  8. Study on adaptability of polycarboxylic admixture and clay in sand%聚羧酸外加剂与砂含泥量的适应性研究

    Institute of Scientific and Technical Information of China (English)

    于涛; 张亮; 周钰沦; 魏振; 房桂明; 赵俊

    2012-01-01

    针对混凝土中聚羧酸外加剂与砂含泥量之间的适应性进行了相关试验,研究了砂含泥量对聚羧酸外加剂性能的影响.通过生产用混凝土配合比的试验,并用人工添加含混量的方法,找出砂含混量影响聚羧酸外加剂适应性的程度,并根据试验结果指导实际生产,对细骨料进厂严格控制,从而保证混凝土的各项性能满足施工及技术要求.试验结果表明,随着砂泥含量增加,混凝土拌合物的性能逐渐下降,砂含泥量在3.25%及以下时较好,在6.25%及以下时初始状态较好,1h后的状态一般,大于6.25%时,初始状态较差;砂含泥量在1.25%~6.25%范 围内时,混凝土抗压强度下降不明显,当泥含量大于6.25%时,混凝土抗压强度下降较大.

  9. Odpornost betona z dodatkom reciklirane gume proti zmrzovanju in tajanju: Freeze-thaw durability of concrete with recycle tire rubber and chemical admixtures:

    OpenAIRE

    Jelušič, Primož; Lubej, Samo; Ivanič, Andrej

    2013-01-01

    Scrap tires and fly ash are being generated and accumulated in large volumes causing an increasing threat to the environment. There are mechanical, environmental and economic reasons to include recycled rubber and fly ash in concrete mixture. The concrete mixture with recycled rubber and fly ash is presented. Concrete used in foundations of non-load bearing structures should be a minimum strength classification of C12/15. In the paper, the freeze-thaw resistance of rubber included concrete wi...

  10. Material and Structural Performance Evaluations of Hwangtoh Admixtures and Recycled PET Fiber-Added Eco-Friendly Concrete for CO2 Emission Reduction

    OpenAIRE

    Bon-Min Koo; Jang-Ho Jay Kim; Sung-Bae Kim; Sungho Mun

    2014-01-01

    In order to reduce carbon dioxide (CO2) emissions and produce an eco-friendly construction material, a type of concrete that uses a minimal amount of cement, yet still retains equivalent properties to ordinary cement concrete, has been developed and studied all over the world. Hwangtoh, a type of red clay broadly deposited around the world, has traditionally been considered an eco-friendly construction material, with bonus advantages of having health and cost benefits. Presently, Hwangtoh is ...

  11. The influence of the composition, admixtures and technique of preparation on surface and bulk properties of hybrid organic-inorganic nanocomposite coatings

    Czech Academy of Sciences Publication Activity Database

    Špírková, Milena; Brus, Jiří; Šlouf, Miroslav; Strachota, Adam; Baldrian, Josef; Strachotová, Beata; Kotek, Jiří

    Istanbul : Tübitak, the Scientific and Technological Research Council of Turkey , 2006 - (Orbay, M.; Somtürk, S.), s. 130-137 ISBN 9944-89-125-8. [International Paint, Varnish Ink & Auxiliary Products Industry Congress & Exhibition /6./. Istanbul (TR), 17.05.2006-19.05.2006] R&D Projects: GA AV ČR IAA400500505 Institutional research plan: CEZ:AV0Z40500505 Keywords : nanocomposite * coating * organic-inorganic hybrid Subject RIV: CD - Macromolecular Chemistry

  12. Effect of different concrete admixtures on the solidification of incinerated sludge ash%污泥焚烧灰固化处理技术研究

    Institute of Scientific and Technical Information of China (English)

    彭丽园; 金艳; 袁海平; 朱南文

    2012-01-01

    The effects of four solidifying agents (Portland cement, aluminate cement, Kaolin and p-naphthalene superplasticizer) on the solidification of incinerated sludge ash were studied in this paper. The compressive strength and the heavy metals leaching toxicity of obtained incinerated sludge ash solidification blocks was measured, and the composition and microstructure of the solidification blocks was detected by XRD and SEM. The results showed that all the four solidifying agents could improve the compressive strength of the solidification blocks. The optimum mixing amount of portland cement, aluminate cement, Kaolin and β-naphthalene superplasticizer were 10, 30, 20 and 1. 0 g respectively. The XRD and SEM analysis showed that the structure of the solidification blocks was dense; Quartz, CaAl2Si2Os, Ca2 Al2SiO7 and other materials could be found in solidification blocks, they were presumed to be beneficial to improve the compressive strength of the solidification blocks.%研究了硅酸盐水泥、高铝水泥、高岭土和β-萘系减水剂在污泥焚烧灰固化技术中的应用效果.考察了污泥焚烧灰固化块(以下简称固化块)的抗压强度,测定了固化块的重金属浸出毒性,并采用X射线衍射(XRD)和扫描电镜(SEM)分析固化块组成和微观结构.结果表明,4种物质对提高固化块的抗压强度均具有较好的效果,硅酸盐水泥、高铝水泥、高岭土和β-萘系减水剂的适宜掺量分别为10、30、20、1.0 g(以100 g污泥焚烧灰中掺加的质量计).XRD和SEM分析结果显示,经固化处理后制得的固化块结构密实,存在石英( SiO2)、水化硅铝酸钙(CaAl2 Si2 O8)和水化硅酸铝钙(Ca2 Al2 SiO7)等物质,其中水化硅铝酸钙等凝胶物质有利于提高固化块的抗压强度.

  13. Nuclear and mitochondrial DNA markers indicate unidirectional gene flow of Indo-Pacific to Atlantic bigeye tuna (Thunnus obesus) populations, and their admixture off southern Africa

    OpenAIRE

    Durand, Jean-Dominique; Collet, Adeline; Chow, S; Guinand, B.; Borsa, Philippe

    2005-01-01

    A sharp genetic break separates Atlantic from Indo-Pacific bigeye tuna (Thunnus obesus) populations, as the frequencies of two major mitochondrial (mt) DNA types (alpha and beta) found in this species are different across the tip of southern Africa. The level of nucleotide divergence between mtDNA types alpha and beta is of the same order as that between reproductively isolated taxa. To further investigate the genetic structure of bigeye tuna over its distribution range and in the contact zon...

  14. 医院静脉用药调配中心的临床意义%Clinical significance of hospital pharmacy intravenous admixture center

    Institute of Scientific and Technical Information of China (English)

    邓永忠

    2015-01-01

    本文对静脉用药调配中心的临床作用进行总结,从提高临床护理工作效率、预防职业暴露,加强职业防护、安全用药、提升医院药师综合素质、搭建药护协作平台、经济社会效益等方面进行阐述。%Summary the clinical effect of intravenous drug allocation center, in order to improve the clinical nursing work efficiency, prevent the occupation exposure, strengthening occupation protection, safety, enhance the comprehensive quality of hospital pharmacists, build of medicine and nursing cooperation platform, economic and social benefit are expounded.

  15. THE UP-TO-DATE DEVELOPMENT OF THE CONCRETE CHEMICAL ADMIXTURE%混凝土化学外加剂的最新发展与动态

    Institute of Scientific and Technical Information of China (English)

    王栋民; 金欣; 何丹; 姚燕

    2001-01-01

    本文综合介绍了国外混凝土化学外加剂的最新发展与动态。并结合作者自身的研究工作和我国国内目前的市场状况和研究开发水平,进行了系统的分析与评价,指出了我国混凝土化学外加剂的出路与发展方向。

  16. The Influence of CO2 Admixtures on the Product Composition in a Nitrogen-Methane Atmospheric Glow Discharge Used as a Prebiotic Atmosphere Mimic

    Science.gov (United States)

    Mazankova, V.; Torokova, L.; Krcma, F.; Mason, N. J.; Matejcik, S.

    2016-04-01

    This work extends our previous experimental studies of the chemistry of Titan's atmosphere by atmospheric glow discharge. The Titan's atmosphere seems to be similarly to early Earth atmospheric composition. The exploration of Titan atmosphere was initiated by the exciting results of the Cassini-Huygens mission and obtained results increased the interest about prebiotic atmospheres. Present work is devoted to the role of CO2 in the prebiotic atmosphere chemistry. Most of the laboratory studies of such atmosphere were focused on the chemistry of N2 + CH4 mixtures. The present work is devoted to the study of the oxygenated volatile species in prebiotic atmosphere, specifically CO2 reactivity. CO2 was introduced to the standard N2 + CH4 mixture at different mixing ratio up to 5 % CH4 and 3 % CO2. The reaction products were characterized by FTIR spectroscopy. This work shows that CO2 modifies the composition of the gas phase with the detection of oxygenated compounds: CO and others oxides. There is a strong influence of CO2 on increasing concentration other products as cyanide (HCN) and ammonia (NH3).

  17. Testing models of speciation from genome sequences: divergence and asymmetric admixture in Island Southeast Asian Sus species during the Plio-Pleistocene climatic fluctuations

    NARCIS (Netherlands)

    Frantz, L.A.F.; Madsen, O.; Megens, H.J.W.C.; Groenen, M.; Lohse, H.

    2014-01-01

    In many temperate regions, ice ages promoted range contractions into refugia resulting in divergence (and potentially speciation), while warmer periods led to range expansions and hybridization. However, the impact these climatic oscillations had in many parts of the tropics remains elusive. Here, w

  18. Testing models of speciation from genome sequences: divergence and asymmetric admixture in Island South-East Asian Sus species during the Plio-Pleistocene climatic fluctuations

    OpenAIRE

    Frantz, Laurent A F; Madsen, Ole; Megens, Hendrik-Jan; Martien A M Groenen; Lohse, Konrad

    2014-01-01

    In many temperate regions, ice ages promoted range contractions into refugia resulting in divergence (and potentially speciation), while warmer periods led to range expansions and hybridization. However, the impact these climatic oscillations had in many parts of the tropics remains elusive. Here, we investigate this issue using genome sequences of three pig (Sus) species, two of which are found on islands of the Sunda-shelf shallow seas in Island South-East Asia (ISEA). A previous study reve...

  19. Route to enhance the efficiency of organic photovoltaic solar cells - by adding ferroelectric nanoparticles to P3HT/PCBM admixture

    Directory of Open Access Journals (Sweden)

    Black David

    2014-01-01

    Full Text Available We have demonstrated that by adding ferroelectric nanoparticles to poly(3-hexylthiophene (P3HT and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM photovoltaic devices the relative efficiency can be increased compared to the same blend without these nanoparticles. In this work samples of 20 mg/ml concentrations of P3HT and PCBM were prepared in a 1:1 ratio and the samples prepared using ferroelectric barium titanate (BT and strontium titanate (ST nanoparticles in a 1:1:0.5 ratio. The samples were spin coated onto ITO coated glass with a layer of poly(3,4-ethylenedioxythiophenepoly(styrenesulfonate (PEDOT:PSS. A top electrode of aluminium 1 cm2 was deposited. The current-voltage characteristics of the devices were determined using a solar simulator and the absorption characteristics by UV-Vis spectroscopy. The samples with BT and ST exhibited increased absorption around 490 nm and increased open circuit voltage and short circuit current compared to the control P3HT/PCBM sample. The possible mechanism that helps to understand the increase in open circuit voltage and short circuit current is also proposed in this work.

  20. Admixture of Eastern and Western European Red Deer lineages as a result of Postglacial recolonization of the Czech Republic (Central Europe)

    Czech Academy of Sciences Publication Activity Database

    Krojerová-Prokešová, Jarmila; Barančeková, Miroslava; Koubek, Petr

    2015-01-01

    Roč. 106, č. 4 (2015), s. 375-385. ISSN 0022-1503 R&D Projects: GA ČR GA524/09/1569 Institutional support: RVO:68081766 Keywords : gene introgression * hybridization * microsatellites * mtDNA * Quaternary * suture zone Subject RIV: EG - Zoology Impact factor: 2.088, year: 2014

  1. Analysis of irrational medical order in pharmacy intravenous admixture services%静脉用药调配中心不合理医嘱分析

    Institute of Scientific and Technical Information of China (English)

    杨亚鹏; 雷伟

    2015-01-01

    Objective:To analyze the irrationality prescription, to provide reference for promoting clinical rational drug use.Meth-ods:Collected in our hospital from January 2014 to August 2014 in the center of the trial with the static record of irrational prescribing pharmacists side, inductive analysis.Results:Solvent improper selection, concentration problems, frequency and joint improper of drug use, wrong copy of medical order were included in unreasonable medical order.Conclution:The safety and rationality of intravenous thera-py were improved by the pharmacist review of prescription through the platform of PIVAS, Which provided references for clinical rational drug use.%目的:分析静脉用药调配中心常见审方实例,促进临床合理用药。方法:收集我院2014年1月~2014年8月静配中心审方药师记录的不合理处方,归纳分析。结果:不合理医嘱存在问题主要有存在配伍禁忌、溶媒选择不当、给药剂量药浓度不当、给药频次不适宜等问题。结论:通过对静脉用药调配中心处方医嘱的审核、分析与干预,提高了我院静脉药物治疗的安全性、有效性、合理性,促进了临床合理用药,提高了患者满意度。

  2. Effects of isoscalar admixtures on the combined analysis of electron-nucleus and proton-nucleus ''scissors mode'' excitations in the f-p shell

    International Nuclear Information System (INIS)

    In the single j shell approximation, only the isovector amplitudes of electron-nucleus or proton-nucleus scattering contribute to the excitation of 1+ states from the J=0+ targets of even-even nuclei, provided the excitation is a one-step process. However, when configuration mixing is put in, one also obtains contributions from isoscalar amplitudes, which are here studied for various nuclei in the f-p shell endash 44Ti, 46Ti, 48Ti and 50Cr. A comparison of the cross-conjugate pairs 46Ti and 50Cr is made. The decomposition of the electron-nucleus scattering into an orbital and spin part is made. The isoscalar effects are small and are unable to explain the discrepancies between the experimental analysis and the shell model calculations with regards to the variation of the orbit to spin ratio for various nuclei. However, there is probably hidden orbital strength in a state in 50Cr for which the spin and orbit excitation amplitudes interfere destructively

  3. Performance of organic and inorganic substances as inhibitors for chloride-induced corrosion in concrete

    Energy Technology Data Exchange (ETDEWEB)

    Aydin, Oezlem [Gedik University Vocational High School, Istanbul (Turkey); Cizmeciglu, Zeki [Istanbul Commerce University, Istanbul (Turkey)

    2015-02-01

    Studies have been carried out to investigate the concrete corrosion inhibitor performance of silica fume admixture and an admixture of amino alcohols containing organic and inorganic substances. The concrete specimens with and without admixtures were subjected to accelerated corrosion tests to determine the time to corrosion initiation. The results showed that the specimens admixtured with nitrogen containing organic and inorganic inhibitors performed slightly better than concrete specimens with silica fume admixture.

  4. The Physicochemical Evaluation and Applicability of Landolphia owariensis latex as a Release Modulating Agent in its Admixture with Carbosil® in Ibuprofen-loaded Self-Emulsifying Oil Formulations

    OpenAIRE

    N C Obitte; A Chukwu; V I Onyishi; BC N Obitte

    2009-01-01

    Summary: The need to address the problematic gastric irritation side effects and inconsistent bioavailability of most poorly soluble drugs has drawn the attention of researchers to self emulsifying drug delivery system as one of the possible solutions to these problems. Secondly self emulsifying oil formulations good as they may be could be associated with leakage from their hard gelatin capsules. This further motivated the introduction of gelling agents to address this problem. The objective...

  5. Experimental study on retarding cement setting time with admixture of sucrose and superphosphate%蔗糖和过磷酸钙作外加剂延缓水泥凝结时间的试验研究

    Institute of Scientific and Technical Information of China (English)

    冯云; 周胜波

    2006-01-01

    用蔗糖和过磷酸钙分别作外加剂延缓水泥凝结时间的试验研究得出结论:蔗糖和过磷酸钙作为外加剂均可起到较好的缓凝效果,同时对水泥的后期强度也有一定的促进作用.

  6. In situ inhibitor synthesis from admixture of benzaldehyde and benzene-1,2-diamine along with FeCl3 catalyst as a new corrosion inhibitor for mild steel in 0.5 M sulphuric acid

    International Nuclear Information System (INIS)

    Highlights: ► Excellent inhibitive efficiency (97%) was obtained by in situ synthesis. ► Results from electrochemical and weight loss measurements are quite comparable. ► By increasing temperature the inhibition efficiency has not changed noticeably. ► FTIR results proved that 2-phenyl-1H-benzo[d]imidazole synthesized on the surface. ► Quantum chemical reveals benzene ring and N atoms are proper adsorption sites. -- Abstract: Corrosion protection of mild steel in 0.5 M H2SO4 solution was studied using combination of benzene-1,2-diamine and benzaldehyde with FeCl3 to in situ synthesis of new inhibitor at different temperatures employing electrochemical, weight loss, quantum chemical studies and optical microscopy. The electrochemical results represent the combination of these components in the solution shows equal efficiency to the compound which was synthesized in the laboratory which is 2-phenyl-1H-benzo[d]imidazole. To indicate this compound was created on the metal surface, deposited layer was investigated by Fourier transform infrared spectroscopy (FTIR). Optical microscopy examinations demonstrate a decrease in corrosion attacks in presence of inhibitors

  7. Test of polycarboxylates high performance water reducing admixture confect Ultra High Performance Concrete and application%高性能减水剂配制超高性能混凝土的试验与应用

    Institute of Scientific and Technical Information of China (English)

    柯科杰; 李伟中; 陶思佺; 李桂青; 黄仕阶; 庄建坤; 邬超友; 李天浪

    2008-01-01

    主要介绍聚羧酸KJ-JS高性能减水剂的主要性能,配制C50~C100超高性能混凝土(UHPC)的试验与应用.试验结果表明:选用质量优良的常规材料,用300kg/m3水泥(粤秀P·II 42.5R,下同)与50%左右的掺合料可配制C80~C90 HPC,28 d强度达102~110MPa;370kg/m3水泥与37%掺合料配制C90 HPC,坍落度与扩展度保持近4 h,28 d强度达104 Mpa;370~400 kg/m3水泥与35%~37%的掺合料配制C100HPC,28d强度达115MPa.现已在432m高的国内在建第二高楼广州西塔与世界最高(610m)的广州新电视塔,以及客运专线等重大工程150多万m3 C25~C100HPC工程中广泛应用.在广州西塔C70~C100HPC工程应用表明:用560(水泥410)~635(水泥430)kg/m3胶凝材料,可配制出28d平均强度达84~112.7MPa满足工程要求的高性能混凝土.目前主楼已达到200m以上,用量已超过2万m3.如此大批量超高性能混凝土的应用在国内尚属首次.

  8. 蒸养条件下不同种类外加剂对水泥水化进程的影响%Effect of Different Kinds of Admixture on Process of Cement Hydration under Steam-curing

    Institute of Scientific and Technical Information of China (English)

    肖茜; 伍勇华; 南峰; 何廷树; 李论

    2013-01-01

    用直接测温法、X射线半定量分析方法,系统研究了蒸养条件下高效减水剂(聚羧酸高效减水剂、萘系高效减水剂)、早强剂(硫酸钠)和引气剂(十二烷基硫酸钠)对硅酸盐水泥的放热量和蒸养强度的影响.研究结果表明,聚羧酸高效减水剂延缓了水化放热温峰出现的时间,水化热和Ca(OH)2生成量明显减少;萘系高效减水剂和硫酸钠使水化热温峰出现的时间提前并随水化热量的增多蒸养强度提高,Ca(OH):生成量增加;十二烷基硫酸钠对水泥水化热几乎没有影响,蒸养强度随十二烷基硫酸钠掺量的增加而降低,Ca(OH)2生成量没有明显变化.%By using direct thermometry and X-ray diffraction technique,the influences of superplasticizer (such as polycarboxylate superplasticizer and naphthalene superplasticizer),early strength agent(such as Na2SO4)and air-entraining agent(such as sodium dodecyl sulfate)on cement hydration heat and strength under steam curing were investigated.The results showed that polycarboxylate superplasticizer could postpone the temperature peak,and reduce the hydration heat and the quantity of Ca (OH)2.Nfaphthalene superplasticizer and Na2SO4 used could obviously advance the temperature peak.With the increase of hydration heat,the strength under steam curing obviously was improved and the quantity of Ca (OH) 2 increased.The sodium dodecyl sulfate had little effect on the hydration heat of the cement.The strength under steam curing was reduced with the increase of dosage of Sodium dodecyl sulfate and the quantity of Ca(OH)2 had no clear change.

  9. STYDY ON PERFORMANCE OF POLYCARBOXYLATE COMPOUNDED WITH ANTI-FREEZING ADMIXTURE%聚羧酸高效减水剂与防冻组分复合研究

    Institute of Scientific and Technical Information of China (English)

    王子明; 孙俊

    2008-01-01

    采用正交设计方法对聚羧酸系高效减水剂与防冻外加剂复合性能进行了研究.掺入聚羧酸系减水剂与防冻组分的胶砂试件中在(-15±1)℃环境下冷冻7d,并测定其胶砂抗压抗折强度.然后通过正交极差分析确定出防冻组分最佳配比并进行优化试验.进而进行单组分优化试验,比较不同防冻组分掺量对胶砂试件抗冻性的影响.

  10. Research on the reuse of expired juice in polycarboxylic admixtures%过期果汁在聚羧酸外加剂中的再利用研究

    Institute of Scientific and Technical Information of China (English)

    陈涛; 邓最亮; 陈健; 王亚妹; 杜维上; 李飞

    2012-01-01

    使用过期果汁作为混凝土外加剂的缓凝保塑剂,研究了过期果汁对混凝土状态和性能的影响,试验结果表明:过期果汁的加入并未影响混凝土的强度和状态,其所起保坍缓凝的效果与葡萄糖酸钠相当;在掺量较大时,对混凝土凝结时间的延长效果要优于葡萄糖酸钠,特别是对终凝时间的影响,且对混凝土的初始状态有一定的改善,而对抗压强度和外观不会造成负作用.

  11. 聚羧酸减水剂在水泥自流平砂浆中的应用%Application of the Polycarboxylate Water-reducing Admixture (PCA) in Self-leveling Cement Mortar

    Institute of Scientific and Technical Information of China (English)

    徐景会; 顾军; 封孝信

    2008-01-01

    对聚羧酸减水剂在水泥自流平砂浆中的应用进行了研究,认为聚羧酸减水剂适用于水泥自流平砂浆并且具有较高的性价比,但在水泥自流平砂浆面层配方设计中应注意气泡问题.

  12. 聚羧酸减水剂对水泥浆体早期单碳铝酸钙形成的影响%Early calcium monocarboaluminate hydrate formation in cement paste: effect of polycarboxylate type admixture

    Institute of Scientific and Technical Information of China (English)

    蒋亚清; 张思佳; 刘小艳; D.Damidot

    2010-01-01

    利用傅里叶红外光谱(FTIR)、扫描电子显微镜(SEM)、热重分析(DTG)和等温吸附,研究了合石灰石填料(LF)水泥在掺用聚羧酸减水剂(PCA)时,硬化浆体中单碳型水化碳铝酸钙(AFmc)的形成规律.研究发现,水泥在水化15 min的初始期就形成了AFmc,PCA通过促进早期C4AF水化使含铁的AFmc更易形成.以萘磺酸盐缩合物减水剂取代PCA时,未观察到相同现象.由于浆体中AFmc和钙矾石(AR)的共存,减少了水泥矿物对PCA的吸附量,从而改善了PCA与水泥的适应性.因此,当混凝土中掺用LF时,PCA应作为首选的高效减水剂.

  13. On the polycarboxylic acid admixture suitability in the high performance concrete%高性能混凝土中聚羧酸外加剂相适应性探讨

    Institute of Scientific and Technical Information of China (English)

    王涛

    2009-01-01

    通过高性能混凝土配合比试验,发现聚羧酸类外加剂对原材料的适应性很敏感,结合实践对影响适应性的因素进行了简单的分析,以减小聚羧酸减水剂的不适应性,使其在高性能混凝土中发挥优势作用.

  14. 新型聚羧酸系超早强复合减水剂试验研究%EXPERIMENTAL INVESTIGATION ABOUT THE NEOTYPE POLYCARBOXYLATE-BASED HARDENING ACCELERATING AND WATER REDUCING ADMIXTURE

    Institute of Scientific and Technical Information of China (English)

    王子明; 刘进强

    2008-01-01

    针对传统早强复合减水剂的缺点,根据功能需要进行设计,利用正交实验方法研究出了一种以聚羧酸系高效减水剂为主体并复合其他早强组分而成的超早强复合减水剂,该减水剂具有无氯离子、无硫酸根、碱含量低,掺量小,减水率高、早期强度发展迅速的特点.

  15. 浅谈《聚羧酸系高性能减水剂》标准与混凝土的质量控制%Polycarboxylates High Performance Water-Reducing Admixture and Concrete Quality

    Institute of Scientific and Technical Information of China (English)

    左彦峰; 郭延辉; 郭京育; 赵霄龙; 薛庆

    2009-01-01

    介绍了(JG/T223-2007)标准的编制背景和主要内容,对标准中的几个重要指标,如影响环境的指标、影响混凝土耐久性的指标、减水率、泌水率比、含气量、混凝土拌合物1h坍落度保留值、凝结时间差、抗压强度比、28d收缩率比及对钢筋的锈蚀作用等进行了较详细地说明和解释,并阐述了该标准的制定对混凝土质量控制的意义.

  16. The Research on Silt Content to the Workability of Polycarboxylate Admixture in Aggregates%骨料中含泥量对聚羧酸系外加剂工作性能影响的研究

    Institute of Scientific and Technical Information of China (English)

    张丽超

    2013-01-01

    由于混凝土中细骨料的含泥量对于掺有减水剂的混凝土工作性能以及强度都有一定影响,为了保证混凝土质量,开展了针对混凝土中的聚羧酸外加剂和细骨料中含泥量之间适应性的系列研究.先通过水泥净浆试验确定外加剂饱和掺量点,在此基础之上人为地改变细骨料中的含泥量,观察流动度的改变也就是其对于混凝土工作性能的影响.随后在混凝土的配合比中,在掺有外加剂的前提下,将含泥量的比重以5%的增量进行增长,制作了10组试件.通过试件的强度试验对比,研究含泥量与聚羧酸外加剂之间的相容性对混凝土强度的影响.研究发现当含泥量低于3%时只对混凝土的工作性能有影响,高于3%时,强度会伴随含泥量的增加而相对降低.

  17. 聚羧酸外加剂制备C30商品混凝土的试验研究%Experimental research of using polycarboxylic admixture to produce C30 ready-mixed concrete

    Institute of Scientific and Technical Information of China (English)

    郭文山; 孙燎燎

    2009-01-01

    通过调整C30商品混凝土的配合比设计思路,发挥聚羧酸外加剂的高减水作用,降低混凝土中胶凝材料用量及用水量,在保证力学性能的前提下,提高聚羧酸减水剂配制商品混凝土的经济性.

  18. 应用聚羧酸系高性能减水剂生产管桩关键工艺控制%Control of key process about the production of PHC pile which apply high performance polycarboxylate concrete admixtures

    Institute of Scientific and Technical Information of China (English)

    黄红建; 赖兆琼; 谢俊锋; 陈锦光

    2012-01-01

    聚羧酸系高性能减水剂与管桩生产中传统使用的萘系高效减水剂相比具有更优异的性能,但应用时必须对管桩原生产工艺作调整.对聚羧酸高性能减水剂在管桩生产中应用的关键工艺控制及应用中出现问题的解决方法作了详细的阐述.

  19. The application of polycarboxylates water-reducing admixture to passenger dedicated line engineering%聚羧酸系减水剂在客运专线工程中的应用研究

    Institute of Scientific and Technical Information of China (English)

    黄直久

    2009-01-01

    介绍聚羧酸系减水剂在满足铁路客运专线高性能混凝土综合性能方面的能力和特点,分析了工程应用中使用聚羧酸系减水剂存在的一些问题.提出解决聚羧酸系减水剂与水泥的相容性问题以及保持聚羧酸系减水剂本身质量稳定性是目前该减水剂应用的关键.

  20. Application of HP-400 Polycarboxylate Admixture in ChaoTianMen Bridge%聚羧酸系HP-400外加剂在朝天门大桥工程中的应用

    Institute of Scientific and Technical Information of China (English)

    汤生虎; 汪存书; 陈爱东

    2007-01-01

    本文详细介绍HP-400聚羧酸外加剂在重庆朝天门大桥混凝土中的应用情况,工程实践证明,聚羧酸系HP-400外加剂具有掺量低、减水率高、坍落度损失小、混凝土拌合物工作性能好、混凝土外观质量好等特点,能较好地保证工程质量.

  1. 聚羧酸系高性能减水剂在梅溪河大桥工程中的应用研究%Research on the Application of Polycarboxylates High Performance Water-reducing Admixture in Meixihe Bridge Engineering

    Institute of Scientific and Technical Information of China (English)

    李健强; 姜华贵

    2010-01-01

    介绍聚羧酸高性能减水剂在梅溪河大桥主梁高性能混凝土中的选择与应用,通过与其他品种聚羧酸高效减水剂及奈系高效减水剂对比试验,结果表明聚羧酸高校减水剂18Rcc具有低掺量、高减水率、高工作性能的优点,提高强度效果好,是适合施工现场的优良外加剂之一.

  2. 聚羧酸系减水剂在预拌混凝土中的应用%The application of polycarboxylates high performance water-reducing admixture in ready-mixed concrete

    Institute of Scientific and Technical Information of China (English)

    林天津; 林荣颂

    2008-01-01

    聚羧酸系减水剂主要在重要、特殊工程进行使用,在预拌混凝土中的使用总结介绍较少,本文通过几年来预拌混凝土中使用聚羧酸系减水剂,谈谈聚羧酸系减水剂的选用、合理掺量、配合比设计等一些经验.

  3. The Synthesis Research of a Kind of Novel Polycarboxylic Acid Slump Retaining Admixture%一种新型聚羧酸系保坍剂的合成研究

    Institute of Scientific and Technical Information of China (English)

    王志超; 丁广广

    2014-01-01

    根据减水剂的“吸附-分散”作用机理,通过一步法使改性聚醚与不饱和羧酸共聚,在引入阴离子表面活性基团的条件下,制备出一种具有羧基、羟基、磺酸基等阴离子活性基团的高性能聚羧酸保坍剂.通过对掺加该聚羧酸保坍剂进行水泥净浆流动度试验、混凝土应用性能试验,测试聚羧酸保坍剂的性能.

  4. BTC功能型外加剂在机制砂混凝土中的应用研究%BTC functional admixture in the mechanism of sand concrete application research

    Institute of Scientific and Technical Information of China (English)

    王浩; 余谷生; 董德生

    2015-01-01

    BTC功能型外加剂做为一种复合型混凝土添加剂,能与聚羧酸减水剂产生“配伍效应”,其在混凝土体系中分散效果明显好于单掺混凝土减水剂。针对机制砂混凝土体系,BTC功能型外加剂的掺入能有效提高混凝土流动性及和易性,同时在不降低混凝土强度的前提下有效降低单位立方米混凝土胶凝材料用量。通过本技术手段可有效利用机制砂作为混凝土细骨料,并降低混凝土单位立方米成本。%BTC functional additive has a compatibility effect on polycarboxylate superplasticizer as a composite concrete additive. Its dispersion effect is much better than the water reducing agent only mixed in the concrete system. In view of the mechanism of sand con-crete system,BTC functional additive can improve the liquidity and workability of the concrete who can also reduce the unilateral con-crete gelled material consumption without reducing the strength of concrete. So the mechanism of this technology can use sand as fine aggregate concrete effectively,and reduce the cost of concrete unilaterally.

  5. Effects of Sand on the Polycarboxylate Admixture, Concrete Content and Strength%砂对聚羧酸掺量、砼用水量、强度的影响

    Institute of Scientific and Technical Information of China (English)

    樊伟忠

    2013-01-01

    This paper through the test systematical y under-stand the ef ects of the sand mud content, fineness modulus of raw materials on performance of concrete mixture, water cont-ent, strength and polycarboxylic acid dosage, provides the bas-is to guide the actual production and timely adjust the mix.%本文通过试验系统了解原材料砂含泥量、细度模数对混凝土拌合物性能、用水量、强度及聚羧酸掺量的影响,为指导实际生产及时调整配合比提供依据。

  6. 三种聚羧酸系外加剂与水泥的相容性对比试验%Comparative Test on Compatibility of Three Series of Polycarboxylate Admixtures with Cement

    Institute of Scientific and Technical Information of China (English)

    于修站; 张广泰; 王万兴

    2009-01-01

    研究了新疆市场上三种聚羧酸系外加剂与乌鲁木齐地区的三大品牌的普通硅酸盐42.5水泥的相容性.得出结论:三种水泥与聚羧酸系外加剂的相容性情况为屯河水泥较好,天山水泥其次,青松水泥较差.相容性较好的水泥与每一种聚羧酸系外加剂相容性均相对较好,相容性较差的水泥则与每一种外加剂的相容性均相对较差.粉煤灰矿物掺和料对聚羧酸系外加剂与水泥的相容性有较好的调节作用.

  7. Dealkalization of calcium silicate slag and study of using it as cement admixture%硅钙渣脱碱处理及作水泥混合材的研究

    Institute of Scientific and Technical Information of China (English)

    刘江; 张建波; 孙俊民; 王宏霞; 叶家元; 史迪

    2012-01-01

    Orthogonal experiment method is applied to research on dealkalization of calcium silicate slag, and properties of non-dealkalizated and dealkalizated calcium slag cement have been analyzed. Effects of temperature, holding time, content of lime milk and washing times were discussed, the results show that the optimum dealkalization combination of the four factors is as follows:content of lime milk is 10%,temperature 85 X. and holding time 3 hours,washing twice,then an alkali content of 0.83% will be acquired; compressive strength of non梔ealkalizated calcium slag cement is higher than dealkalizated calcium slag cement during the early hydration, the advantages of dealkalizated calcium slag cement will gradually appear as time goes and will be more significantly as calcium slag content increase; Microscopic analysis shows that non-dealkalizated calcium slag cement generates large amount of C-S-H gel during early hydration and its hydration products are more compact than dealkalizated calcium slag cement, little difference of the compactness has been found between them when the hydration time is 28 days.%采用正交试验法对硅钙渣进行脱碱处理,对脱碱前后的硅钙渣水泥性能进行了研究.通过调整温度、保温时间、石灰乳掺量和水洗次数,得出最佳脱碱组合为:石灰乳掺量10%,温度85℃,保温时间3h,水洗2次,处理后碱含量为0.83%:强度试验结果表明,水化早期未脱碱硅钙渣水泥抗压强度要高于脱碱硅钙渣水泥,但随着龄期逐渐增长,脱碱硅钙渣水泥优势逐渐显现,掺量越大优势越明显;微观形貌分析表明,未脱碱硅钙渣水泥水化早期生成大量C-S-H凝胶,水化产物较脱碱硅钙渣水泥更致密,水化28d时两者水化产物的致密性相当.

  8. Analysis of Errors in Pharmacy Intravenous Admixture Service of Our Hospital and Preventive Measures%我院静脉用药调配中心差错分析及防范

    Institute of Scientific and Technical Information of China (English)

    邓雪娥

    2011-01-01

    本文收集了北京友谊医院静脉用药调配中心2011年1至6月期间出现的各类差错,并对此进行分析,其中内差错发生率为1.44‰,出门差错发生率为0.105‰.,主要发生在调剂、配置和成品输液核对等多个环节,针对这些问题提出了具体防范措施,以减少PIVAS差错,保障患者用药安全.%The article collected various errors in PIVAS of Beijing Friendship Hospital from January 2011 to June 2011, and analyzed the occurrence of the errors according to drug package inserts, Chinese Pharmacopoeia, Clinical Medication Information, Pharmaceutical incompatibility in intravenous infusion and clinical drug consulting system. The external ratio of errors in PIVAS was 0.105%o, and the internal ratio of errors was 1.44%o. The errors occurred mainly were errors of making up prescriptions, dispensing errors and errors of checking finished products. Meanwhile, PIVAS adopted the targeted preventive measures according to the reasons and to cut down the mistakes in order to guarantee safe drug of patients.

  9. Effect of cholera toxoid-proinsulin conjugate and cholera toxin B subunit admixtures on spontaneous autoimmune diabetes%霍乱毒素B亚单位-胰岛素原融合蛋白抗糖尿病

    Institute of Scientific and Technical Information of China (English)

    高玲; 张大兵; 任宏; 欧阳凤秀; 姜庆五

    2005-01-01

    目的观察雌性非肥胖糖尿病(NOD)小鼠口服胰岛素和霍乱毒素B亚单位-胰岛素原融合蛋白(CTB-proinsulin)+霍乱毒素B亚单位五聚体(CTB五聚体)对糖尿病发生的影响,为社区非肥胖性糖尿病干预提供参考依据.方法40只雌性3~4周龄NOD小鼠随机分为4组:分别给予磷酸缓冲液(PBS)500μl,胰岛素(insulin)1 mg,CTB-proinsulin 100μg+CTG五聚体1μg,CTB-proinsulin 300μg+CTG五聚体3μg.每周灌胃2次至12周龄;从12周龄起,动态监测小鼠尿糖、血糖至26周龄,观察糖尿病的发生,比较不同抗原诱导免疫耐受的作用.结果与PBS组比较,CTB-proinsulin+CTG五聚体与胰岛素均能延缓、减少NOD小鼠糖尿病的发生,26周龄时小鼠糖尿病的累积发病率:PBS组100%,CTB-proinsulin100μg+CTG五聚体1μg组、CTGproinsulin 300μg+CTG五聚体3μg组和胰岛素组分别为40%,40%和50%(P<0.010).各组生存时间分布有差别.结论不同剂量组的CTB-proinsulin+CTG五聚体与胰岛素能够提高NOD鼠生存率,并可达到与胰岛素相同保护作用而所需抗原剂量较小.

  10. Relationship Between Electrical Property and Microstructure of Mineral Admixtures-Cement Paste%矿物掺和料-水泥浆体电学特性与其微结构的关系

    Institute of Scientific and Technical Information of China (English)

    李化建; 万广培; 谢永江; 黄佳木

    2013-01-01

    The electrical properties of fly ash ,slag and limestone powder-cement paste were studied by the methods of Cyclic Voltammetry and AC Impedance Spectroscopy .The results of electrical test were fitted by equivalent circuit . The correlations between electrical parameters of paste and unevaporable water content ,pore structure by mercury porosimetry were compared .The results show that there is a positive relation between the unevaporable water content and the electrical resistivity of paste .If the unevaporable water content is higher ,the hydration degree is higher and the electrical resistivity of paste is higher .The electrical resistivity of paste is increased with fly ash and slag ,and it is unaffected with limestone powder of 5% dosage .The resistance Rs of pore solution of paste is increased with the prolongation of hydration ,and the changes of resistance Rs and the electrical resistivity are unanimous .The resistance Rp and electrical capacitance C of gel are related to C -S-H content ,and there is a negative relation between the resistance Rp and electrical capacitance C of gel . The complexity of pore structure of paste is increased with the prolongation of hydration . T he constant phase angle exponent P by AC Impedance Spectroscopy is decreased and the value of fractal dimension by mercury porosimetry is increased .%采用循环伏安法和交流阻抗法系统研究了粉煤灰、矿渣粉和石灰石粉水泥浆体的电学特性,通过等效电路对电学测试结果进行拟合,并将拟合所得浆体电学参数与浆体化学结合水和压汞所测孔结构之间的相关性进行比较。结果表明:浆体的化学结合水与其电阻率具有较好的正相关性,即化学结合水越多,水化程度越大,浆体电阻率越高;粉煤灰和矿渣粉可以提高浆体电阻率,而石灰石粉在5%掺量下对浆体电阻率无影响;随着水化龄期的延长,浆体孔溶液电阻增大,其变化规律与浆体电阻率一致;浆体凝胶电容和凝胶电阻与C -S -H凝胶含量有关,二者有很好的负相关性;随着水化龄期的延长,浆体孔结构曲折程度提高,交流阻抗法所测得常相角指数减小,压汞测得的分形维数增大。

  11. Circulating Endocannabinoids and the Polymorphism 385C>A in Fatty Acid Amide Hydrolase (FAAH Gene May Identify the Obesity Phenotype Related to Cardiometabolic Risk: A Study Conducted in a Brazilian Population of Complex Interethnic Admixture.

    Directory of Open Access Journals (Sweden)

    Cyro José de Moraes Martins

    Full Text Available The dysregulation of the endocannabinoid system is associated with cardiometabolic complications of obesity. Allelic variants in coding genes for this system components may contribute to differences in the susceptibility to obesity and related health hazards. These data have mostly been shown in Caucasian populations and in severely obese individuals. We investigated a multiethnic Brazilian population to study the relationships among the polymorphism 385C>A in an endocannabinoid degrading enzyme gene (FAAH, endocannabinoid levels and markers of cardiometabolic risk. Fasting plasma levels of endocannabinoids and congeners (anandamide, 2-arachidonoylglycerol, N-oleoylethanolamide and N-palmitoylethanolamide were measured by liquid chromatography-mass spectrometry in 200 apparently healthy individuals of both genders with body mass indices from 22.5 ± 1.8 to 35.9 ± 5.5 kg/m2 (mean ± 1 SD and ages between 18 and 60 years. All were evaluated for anthropometric parameters, blood pressure, metabolic variables, homeostatic model assessment of insulin resistance (HOMA-IR, adiponectin, leptin, C-reactive protein, and genotyping. The endocannabinoid levels increased as a function of obesity and insulin resistance. The homozygous genotype AA was associated with higher levels of anandamide and lower levels of adiponectin versus wild homozygous CC and heterozygotes combined. The levels of anandamide were independent and positively associated with the genotype AA position 385 of FAAH, C-reactive protein levels and body mass index. Our findings provide evidence for an endocannabinoid-related phenotype that may be identified by the combination of circulating anandamide levels with genotyping of the FAAH 385C>A; this phenotype is not exclusive to mono-ethnoracial populations nor to individuals with severe obesity.

  12. Reducing Dispensing Errors in Pharmacy Intravenous Admixture Service by Using Six Sigma DMAIC Method%利用六西格玛改进方法减少静脉药物配置中心排药差错

    Institute of Scientific and Technical Information of China (English)

    史文秀; 张久星; 隋颖; 李娜; 赵春芝

    2009-01-01

    目的:寻找减少静脉用药集中配置各环节差错的有效途径.方法:利用六西格玛改进方法分5个阶段评价静脉药物配置中心原有排药流程,去除原有的标签分篮环节和复核环节,将原有的排药品、贴输液标签环节分成"粗排"和"细排"2个步骤,并增加了统计单控制单个病区用药数量.结果与结论:干预后静脉药物配置中心的排药差错率由2.21次/日降到0.49次/日,比目标值(1次/日)低约50%.新流程更简单、省时,可操作性更好,在差错的预防和监控方面较之原流程有很大的优势,从而提高了静脉用药的准确性和安全性.

  13. The application and effectiveness of six sigma in pharmacy intravenous admixture service%六西格玛管理原理在输液配置中心的运用及成效

    Institute of Scientific and Technical Information of China (English)

    方芳

    2004-01-01

    目的提高输液配置中心的工作效率和工作质量,保证药液及时、准确送至病区.方法通过持续性质量改进体系和六西格玛五步法即定义、测量、分析、改进、控制对输液配置中心进行管理,定义项目问题为药物无法及时、准确地派送至病区;测量并分析该问题存在的原因包括影响配药准确性因素及影响送药及时性因素;制订质量改进方案,改进排班的合理性,降低冲配步骤的复杂性,采取减少各类操作错误的措施;将改进措施形成常规工作制度并进行控制.结果保证药液能在9:30之前准确、及时地送至病区.结论合理、有效地运用定量管理与定性管理协调发展的管理理念,可以达到提高工作质量和工作效率的目的.

  14. Circulating Endocannabinoids and the Polymorphism 385C>A in Fatty Acid Amide Hydrolase (FAAH) Gene May Identify the Obesity Phenotype Related to Cardiometabolic Risk: A Study Conducted in a Brazilian Population of Complex Interethnic Admixture.

    Science.gov (United States)

    Martins, Cyro José de Moraes; Genelhu, Virginia; Pimentel, Marcia Mattos Gonçalves; Celoria, Bruno Miguel Jorge; Mangia, Rogerio Fabris; Aveta, Teresa; Silvestri, Cristoforo; Di Marzo, Vincenzo; Francischetti, Emilio Antonio

    2015-01-01

    The dysregulation of the endocannabinoid system is associated with cardiometabolic complications of obesity. Allelic variants in coding genes for this system components may contribute to differences in the susceptibility to obesity and related health hazards. These data have mostly been shown in Caucasian populations and in severely obese individuals. We investigated a multiethnic Brazilian population to study the relationships among the polymorphism 385C>A in an endocannabinoid degrading enzyme gene (FAAH), endocannabinoid levels and markers of cardiometabolic risk. Fasting plasma levels of endocannabinoids and congeners (anandamide, 2-arachidonoylglycerol, N-oleoylethanolamide and N-palmitoylethanolamide) were measured by liquid chromatography-mass spectrometry in 200 apparently healthy individuals of both genders with body mass indices from 22.5 ± 1.8 to 35.9 ± 5.5 kg/m2 (mean ± 1 SD) and ages between 18 and 60 years. All were evaluated for anthropometric parameters, blood pressure, metabolic variables, homeostatic model assessment of insulin resistance (HOMA-IR), adiponectin, leptin, C-reactive protein, and genotyping. The endocannabinoid levels increased as a function of obesity and insulin resistance. The homozygous genotype AA was associated with higher levels of anandamide and lower levels of adiponectin versus wild homozygous CC and heterozygotes combined. The levels of anandamide were independent and positively associated with the genotype AA position 385 of FAAH, C-reactive protein levels and body mass index. Our findings provide evidence for an endocannabinoid-related phenotype that may be identified by the combination of circulating anandamide levels with genotyping of the FAAH 385C>A; this phenotype is not exclusive to mono-ethnoracial populations nor to individuals with severe obesity. PMID:26561012

  15. Circulating Endocannabinoids and the Polymorphism 385C>A in Fatty Acid Amide Hydrolase (FAAH) Gene May Identify the Obesity Phenotype Related to Cardiometabolic Risk: A Study Conducted in a Brazilian Population of Complex Interethnic Admixture

    OpenAIRE

    Martins, Cyro José de Moraes; Genelhu, Virginia; Pimentel, Marcia Mattos Gonçalves; Celoria, Bruno Miguel Jorge; Mangia, Rogerio Fabris; Aveta, Teresa; Silvestri, Cristoforo; Di Marzo, Vincenzo; Francischetti, Emilio Antonio

    2015-01-01

    The dysregulation of the endocannabinoid system is associated with cardiometabolic complications of obesity. Allelic variants in coding genes for this system components may contribute to differences in the susceptibility to obesity and related health hazards. These data have mostly been shown in Caucasian populations and in severely obese individuals. We investigated a multiethnic Brazilian population to study the relationships among the polymorphism 385C>A in an endocannabinoid degrading enz...

  16. Genomic Data Reveal a Complex Making of Humans

    OpenAIRE

    Alves, Isabel; Srámková Hanulová, A.; Foll, Matthieu; Excoffier, Laurent

    2012-01-01

    In the last few years, two paradigms underlying human evolution have crumbled. Modern humans have not totally replaced previous hominins without any admixture, and the expected signatures of adaptations to new environments are surprisingly lacking at the genomic level. Here we review current evidence about archaic admixture and lack of strong selective sweeps in humans. We underline the need to properly model differential admixture in various populations to correctly reconstruct past demograp...

  17. Технологічні схеми очистки металомістких стічних вод від органічних домішок

    OpenAIRE

    Филипчук, Віктор

    2002-01-01

    Technological schemes and experimental data are given of purification metalcontaining multicomponent waste waters of industrial enterprises from heavy metals ions with synchronous extraction of organic admixtures.

  18. The influence of sulfuric environments on concretes elaborated with sulfate resistant cements and mineral admixtures. Part 1: Concrete exposed to Sodium Sulfate (Na2SO4) = Estudio de la influencia de los medios con presencia de sulfatos en hormigones con cementos sulforresistentes y adiciones minerales. Parte 1: Hormigones expuestos a sulfato sódico (Na2SO4)

    OpenAIRE

    Bernal Camacho, Jesús Manuel; Mahmoud Abdelkader, Safwat; Reyes Pozo, Encarnación; Moragues Terrades, Amparo

    2013-01-01

    The study of sulfate attack in concrete is considered vital for the preservation of the structural integrity of constructions. Its aggressive behaviour causes degradation of the cement matrix which changes the initial properties of the material. In this article, the sulfate resistance of concrete is studied. To that goal, four different concrete mixes were made with sulphur resistant cement. The concretes were tested for compressive strength, transport capacity of sulfates and microstructural...

  19. A 1H NMR-based metabolomics approach to evaluate the geographical authenticity of herbal medicine and its application in building a model effectively assessing the mixing proportion of intentional admixtures: A case study of Panax ginseng: Metabolomics for the authenticity of herbal medicine.

    Science.gov (United States)

    Nguyen, Huy Truong; Lee, Dong-Kyu; Choi, Young-Geun; Min, Jung-Eun; Yoon, Sang Jun; Yu, Yun-Hyun; Lim, Johan; Lee, Jeongmi; Kwon, Sung Won; Park, Jeong Hill

    2016-05-30

    Ginseng, the root of Panax ginseng has long been the subject of adulteration, especially regarding its origins. Here, 60 ginseng samples from Korea and China initially displayed similar genetic makeup when investigated by DNA-based technique with 23 chloroplast intergenic space regions. Hence, (1)H NMR-based metabolomics with orthogonal projections on the latent structure-discrimination analysis (OPLS-DA) were applied and successfully distinguished between samples from two countries using seven primary metabolites as discrimination markers. Furthermore, to recreate adulteration in reality, 21 mixed samples of numerous Korea/China ratios were tested with the newly built OPLS-DA model. The results showed satisfactory separation according to the proportion of mixing. Finally, a procedure for assessing mixing proportion of intentionally blended samples that achieved good predictability (adjusted R(2)=0.8343) was constructed, thus verifying its promising application to quality control of herbal foods by pointing out the possible mixing ratio of falsified samples. PMID:26942336

  20. 聚羧酸系高效减水剂在跨海特大桥高性能混凝土中的应用%The application in crossing-sca bridge high-performance concrete of polycarboxylates high performance water-reducing admixture

    Institute of Scientific and Technical Information of China (English)

    简杏玲

    2008-01-01

    本文结合集美大桥工程应用的实际情况,阐述了聚羧酸系高效减水剂技术指标的要求及其在跨海特大桥高性能混凝土中的应用情况.集美大桥混凝土结构施工所选用的聚羧酸系高效减水剂较好的满足了工程施工及耐腐蚀性等各项要求.

  1. Test and application of polycarboxylates high performance water-reducing admixture on high performance concret in high speed railway engineering%聚羧酸高性能减水剂在高速铁路高性能混凝土的试验与应用

    Institute of Scientific and Technical Information of China (English)

    李桂青; 黄仕阶; 庄建坤; 柯蕾; 黄耀明; 柯科杰

    2007-01-01

    介绍了聚羧酸KJ-JS高性能减水剂的主要性能,对其在C20~C100高性能混凝土中的配合比、强度与部分耐久性等试验,以及在高速铁路武广客运专线、新广州火车站与温福铁路白马河桥等路桥工程50万m3多C15~C50HPC的工程应用实例,对高性能减水剂在客运专线与其他重大工程的高性能混凝土的配制与应用具有一定的参考价值.

  2. Research of polycarboxylates high performance water-reducing admixture in bridge construction concrte%聚羧酸系高性能减水剂在桥梁工程混凝土中应用的对比试验研究

    Institute of Scientific and Technical Information of China (English)

    彭建良

    2008-01-01

    本文结合正在建设中的厦门快速公交路线工程,通过对比试验,探讨了用萘磺酸盐系和聚羧酸系高效减水剂配制的混凝土的性能,结果表明聚羧酸系高性能减水剂用于C50及以上高强、高性能混凝土是其应用发展的重要方向,这方面是奈磺酸盐系高效减水剂所无法比拟的.

  3. On Flexural Behavior of Steel Fiber Reinforced Self-Compacting Concrete Beam of Different Admixture Amounts with Finite Element Analysis%不同掺量钢纤维自密实混凝土梁的抗弯性能有限元分析

    Institute of Scientific and Technical Information of China (English)

    薛瑞; 吴禹; 周俊敏

    2015-01-01

    根据理论计算与试配获得了不同掺量的钢纤维自密实混凝土配合比,由混凝土力学性能试验得到各配合比下混凝土的力学性能指标,并以实测材料参数为依据,通过ANSYS有限元模型,分析不同钢纤维掺量的钢筋自密实混凝土梁的抗弯性能及裂缝分布,并找到最佳钢纤维自密实混凝土配合比,为工程实践提供参考。计算结果表明,掺钢纤维的钢筋自密实混凝土梁,其开裂荷载、屈服荷载、弯曲韧性及结构刚度与普通钢筋自密实混凝土梁相比得到提升,并且实际极限荷载也能得到相应改善。%According to the theoretical calculations and the test results ,the different mixture ratio of steel fiber reinforced self‐compacting concrete has been found in this paper .Based on the results of the concrete mechanics performance test ,through ANSYS finite element analysis the paper gets the results of steel fi‐ber reinforced self‐compacting concrete beams bending performance and fracture distribution with different mixing amount of fiber ,and the best mixture ratio of steel fiber reinforced self‐compacting concrete is found .It can provide a reference for the practical engineering .The calculation of model shows that the cracking load ,yielding load ,flexural toughness and structure stiffness of steel fiber reinforced self‐com‐pacting concrete beams are significantly increased compared with ordinary reinforced self‐compacting con‐crete beams .And it can be reasonably extrapolated that the actual ultimate load also be improved accord‐ingly .

  4. Inhalation solutions: which one are allowed to be mixed? Physico-chemical compatibility of drug solutions in nebulizers.

    Science.gov (United States)

    Kamin, Wolfgang; Schwabe, Astrid; Krämer, Irene

    2006-12-01

    Therapy of chronic respiratory diseases often involves inhalation therapy with nebulizers. Patients often attempt to shorten the time consuming administration procedure by mixing drug solutions/suspensions for simultaneous inhalation. This article considers the issue of physico-chemical compatibility of admixtures of drug solutions/suspensions in nebulizers. A search of databases, prescribing information and primary literature was conducted to locate literature concerning the physico-chemical compatibility of inhalation solutions/suspensions. This was supplemented by telephone interviews. Admixtures of albuterol with ipratropium and/or cromolyn, of albuterol and budesonide, or tobramycin, or colistin are physico-chemically compatible. Physico-chemical compatibility has been demonstrated for admixtures of cromolyn with albuterol and/or ipratropium and for admixtures of cromolyn and budesonide. Admixtures of budesonide with ipratropium and/or fenoterol, and admixtures of budesonide and albuterol, or cromolyn are physico-chemically compatible. Both cromolyn and colistin are incompatible with benzalkonium chloride. Admixtures should be prepared from inhalation solutions/suspensions formulated without preservatives. Besides studies of the physico-chemical compatibility, the aerodynamic behaviour of physico-chemical mixtures needs to be studied before a final recommendation of simultaneous nebulization of compatible admixtures can be made. PMID:16678502

  5. Temperature dependent lattice instability in single crystals of ferromagnetic CdCr2Se4 diluted with In and Sb

    DEFF Research Database (Denmark)

    Waskowska, A.; Gerward, Leif; Olsen, J.S.;

    2008-01-01

    (C-W) decreases for both admixtures, indicating changes in competing ferromagnetic and antiferromagnetic interactions. The magnetization at 2.1 K exhibits saturation for H > 0.6 T. The magnetic moments are mu(sat) = 6.26 and 5.47 mu(B) mol(-1) for Sb and In admixtures, respectively. These values are consistent...

  6. Laboratory and Field Performance of stabilized soft subgrade

    Directory of Open Access Journals (Sweden)

    SATISH SAJJA

    2014-08-01

    Full Text Available Usually the service life of pavement on weaker clayey subgrade is affected due to their high plasticity and compressibility behaviour. These soils possess low strength, CBR value and have high affinity to moisture. Hence seasonal changes affect properties of these soils adversely. Stabilization techniques using waste materials are listed in literature for improving properties of these types of soft subgrades. This paper discusses the performance of stabilized soft clayey soil for suitability as subgrade using two types of admixtures Robo sand and fly ash. Dynamic cone penetration test and CBR tests are carried out in lab and field on composite soil with varying admixture content and the results are presented. It is observed that there is a considerable improvement with admixture in both index & engineering properties. A reduction in plasticity and improvement in soaked CBR with admixture is observed. Results indicated a relatively high performance of robo sand admixture over fly ash.

  7. Elastic scattering of electrons at large momentum transfer and the quark structure of 4He

    International Nuclear Information System (INIS)

    The 4He form factor is investigated within the model where the wave function includes both the nucleon and multiquark admixtures. It is shown that to explain experimental data, one needs 18% of the 6q-admixture and 1% of the 9q one. An estimation is done for the 12q-admixture of the level 0.02%. Contributions of the 6q-, 9q- and 12q-form factors are smaller because of interference of the nucleon and quark channels and their values are 7, 0.8 and 0.01%, respectively

  8. Developing axial flow cyclone separators for nuclear gas cleaning

    International Nuclear Information System (INIS)

    Cyclone separators designed for purification of gas flows from solid admixtures are described. Examples of their application in aviation, nuclear power engineering and at nuclear industry enterprises are presented

  9. 75 FR 57770 - Certain New Chemicals; Receipt and Status Information

    Science.gov (United States)

    2010-09-22

    ... phosphonic, sulfonic and carboxylic acid groups P-10-0530 08/27/10 11/24/10 CBI (G) Polymer admixture (G) Polycarboxylate for cements polymer with alkenyloxyalkylol modified poly(oxyakylenediyl) , sodium salt...

  10. Helium Arc Plasmas as an Efficient Source for Excitation of Spectra of Light Elements

    International Nuclear Information System (INIS)

    Spectroscopic properties of helium arc plasmas with small gaseous admixtures of CO2, N2, and O2 are discussed. From spectral line intensity measurements population densities of selected excited atomic levels are determined. (author)

  11. Sequencing and Analysis of Neanderthal Genomic DNA

    Energy Technology Data Exchange (ETDEWEB)

    Noonan, James P.; Coop, Graham; Kudaravalli, Sridhar; Smith,Doug; Krause, Johannes; Alessi, Joe; Chen, Feng; Platt, Darren; Paabo,Svante; Pritchard, Jonathan K.; Rubin, Edward M.

    2006-06-13

    Recovery and analysis of multiple Neanderthal autosomalsequences using a metagenomic approach reveals that modern humans andNeanderthals split ~;400,000 years ago, without significant evidence ofsubsequent admixture.

  12. Controlling the NO production of an atmospheric pressure plasma jet

    International Nuclear Information System (INIS)

    The production of NO radicals by an atmospheric pressure plasma jet has been investigated by means of absorption spectroscopy in the mid-infrared region (IR) and optical emission spectroscopy (OES) in the ultraviolet (UV) part of the spectrum. The plasma jet investigated here operates in argon with air admixtures up to 1%. The study shows that OES can be used to characterize the relative NO production at small air admixtures. The Production of NO radicals can be controlled by variation of air admixture. Important to note—especially for operation in ambient conditions—is that a small addition of water vapour strongly affects the production of NO radicals especially at higher air admixtures (greater than 0.2%). (paper)

  13. Properties of Cement Mortar with Phosphogpysum under Steam Curing Condition

    Directory of Open Access Journals (Sweden)

    Kyoungju Mun

    2008-01-01

    Full Text Available The purpose of this study is to utilize waste PG as an admixture for concrete products cured by steam. For the study, waste PG was classified into 4 forms (dehydrate, β-hemihydrate, III-anhydrite, and II-anhydrite, which were calcined at various temperatures. Also, various admixtures were prepared with PG, fly-ash (FA, and granulated blast-furnace slag (BFS. The basic properties of cement mortars containing these admixtures were analyzed and examined through X-ray diffraction, scanning electron microscopy, compressive strength, and acid corrosion resistance. According to the results, cement mortars made with III-anhydrite of waste PG and BFS exhibited strength similar to that of cement mortars made with II-anhydrite. Therefore, III-anhydrite PG calcined at lower temperature can be used as a steam curing admixture for concrete second production.

  14. Some observations on use of siliceous mineral waters in reduction of corrosion in RCC structures

    Digital Repository Service at National Institute of Oceanography (India)

    Venugopal, C.

    The corrosion-resisting characteristics of reinforcement in cement blended with siliceous mineral wastes viz. gold tailing and flyash have been evaluated by using an accelerated corrosion technique. The additions of these mineral admixtures...

  15. Modern Technologies of Nondestructive Testing of Construction Materials

    Science.gov (United States)

    Fediuk, R.; Yushin, A.

    2016-06-01

    The article presents the modern methods of research of building materials (such as styrofoam, cement, concrete admixtures, etc.), applied in the Far Eastern Federal University. The latest equipment described for these studies and modern methods of testing.

  16. Effect of bitumen emulsion on setting, strength, soundness and moisture resistance of oxychloride cement

    Indian Academy of Sciences (India)

    M P S Chandrawat; T N Ojha; R N Yadav

    2001-06-01

    Addition of bitumen emulsion to the matrix has been found to improve strength and soundness of the product while decreasing the initial setting periods. Thus, bitumen emulsion as an admixture in magnesia cement is a moisture proofing and strengthening material.

  17. Self-purification in p-CdTe crystals under heat treatment

    International Nuclear Information System (INIS)

    Optimal conditions, accompanied by self-purification from small-sized acceptors in nominally pure p-CdTe crystals, are considered. It is shown that thermal treatment (τ∼=10-102 h) at the temperature of 420-480 C; as associated with self-purification from fine acceptors and donors, conditioned by admixture run-off into the sewer. The above admixtures are assumed to be precipitates and tellurium inclusions. 7 refs., 2 figs., 2 tabs

  18. Influence of polysaccharides on cement hydration

    OpenAIRE

    Peschard, Arnaud; Govin, Alexandre; Fredon, Emmanuel; Grosseau, Philippe; Fantozzi, Gilles

    2004-01-01

    This paper is about the influence of polysaccharides on cement hydration. Three polysaccharides were studied: a cellulose ether (CE), a starch ether (SE) and a dextrin (YD). In a concentrated media as well as in a dilute media, admixture CE only revealed a slight effect on cement hydration. Portlandite and ettringite formation and gypsum consumption were slowed down by SE adjunction. Admixture YD induced an acceleration of ettringite formation as well as gypsum consumption whereas portiandite...

  19. IMPROVING PHYSICAL PROPERTIES OF RAPE BIOFUELS

    OpenAIRE

    Zbigniew Kiernicki

    2012-01-01

    The researches on the use of biodiesel and fuel derived from waste plastics are presented in the paper. Biodiesel and fuel obtained from waste plastics were both used as fuel components. FAME is a bio-admixture in the fuel. The catalytic cracking of polyolefin was the source of second fuel admixture. The physical properties of the analyzed components of fuel have been presented. The operational parameters of direct injection in diesel engines fuelled by tested fuel blends was set out. The pre...

  20. Effect of Superplasticizer on Fresh and Hardened Properties of Self-Compacting Concrete Containing Fly Ash

    OpenAIRE

    S. M. Dumne

    2016-01-01

    The use of mineral and chemical admixtures in concrete is a common solution to achieve full compaction particularly where reinforcement congestion and shortage of skilled workers. The past researchers have been underscored the use of mineral and chemical admixtures imparts the desirable properties to concrete in both fresh and hardened state. This paper has been made an attempt to study the influence of superplasticizer dose of 0.25, 0.30 and 0.35percentage on performance of Self-Compactin...