WorldWideScience

Sample records for rapid growth phase

  1. Tyrosine requirement during the rapid catch-up growth phase of recovery from severe childhood undernutrition

    Science.gov (United States)

    The requirement for aromatic amino acids, during the rapid catch-up in weight phase of recovery from severe childhood under nutrition (SCU) is not clearly established. As a first step, the present study aimed to estimate the tyrosine requirement of children with SCU during the catch-up growth phase ...

  2. Oxidation phase growth diagram of vanadium oxides film fabricated by rapid thermal annealing

    Institute of Scientific and Technical Information of China (English)

    Tamura KOZO; Zheng-cao LI; Yu-quan WANG; Jie NI; Yin HU; Zheng-jun ZHANG

    2009-01-01

    Thermal evaporation deposited vanadium oxide films were annealed in air by rapid thermal annealing (RTP). By adjusting the annealing temperature and time, a series of vanadium oxide films with various oxidation phases and surface morphologies were fabricated, and an oxidation phase growth diagram was established. It was observed that different oxidation phases appear at a limited and continuous annealing condition range, and the morphologic changes are related to the oxidation process.

  3. Rapid population growth.

    Science.gov (United States)

    1972-01-01

    At the current rate of population growth, world population by 2000 is expected to reach 7 billion or more, with developing countries accounting for some 5.4 billion, and economically advanced nations accounting for 1.6 billion. 'Population explosion' is the result of falling mortality rates and continuing high birth rates. Many European countries, and Japan, have already completed what is termed as demographic transition, that is, birth rates have fallen to below 20 births per 1000 population, death rates to 10/1000 population, and annual growth rates are 1% or less; annual growth rates for less developed countries ranged from 2 to 3.5%. Less developed countries can be divided into 3 groups: 1) countries with both high birth and death rates; 2) countries with high birth rates and low death rates; and 3) countries with intermediate and declining birth rates and low death rates. Rapid population growth has serious economic consequences. It encourages inequities in income distribution; it limits rate of growth of gross national product by holding down level of savings and capital investments; it exerts pressure on agricultural production and land; and it creates unemployment problems. In addition, the quality of education for increasing number of chidren is adversely affected, as high proportions of children reduce the amount that can be spent for the education of each child out of the educational budget; the cost and adequacy of health and welfare services are affected in a similar way. Other serious consequences of rapid population growth are maternal death and illness, and physical and mental retardation of children of very poor families. It is very urgent that over a billion births be prevented in the next 30 years to reduce annual population growth rate from the current 2% to 1% per year.

  4. China urges rapid growth

    International Nuclear Information System (INIS)

    Hendry, S.

    1993-01-01

    This time last year China's paramount leader, Deng Xiaoping, launched the country on another bout of fast-paced economic growth and restructuring. After three years of riding out political and economic clampdown, foreign chemical companies were jerked awake by major changes in China's chemical industry. As the state becomes less involved with managing the economy, unleashing 12% gross national product growth, closer involvement with domestic factories has become attractive and essential. MCI officials say government funds will now be channeled toward clearing energy and transport bottlenecks, and chemical enterprises will be given more chance to turn a profit. They will be allowed to issue shares, seek foreign investment partners themselves, and bypass trading companies like China National Import-Export Corp. (Sinochem), the former state monopoly. Foreign analysts question whether China's finances and oil resources can support expansion. Even if they can, Cai estimates that ethylene imports will remain around the present level of 1 million tons. To further guarantee chemical supplies, China has invested in urea and polypropylene plants in the US and polystyrene plant in Hong Kong

  5. Rapid growth within India

    International Nuclear Information System (INIS)

    Hayes, D.

    2000-01-01

    The Indian government has published (in Hydrocarbon Vision 2025) its ideas for a long term strategy for its oil industry which is currently growing at an unprecedented rate. Increasing domestic production and investment in oil exploration and production overseas figure strongly in the plan. At present, India has a refining surplus but with an annual growth of 8-10%, this will disappear in the next 2-3 years. The report recommends that India should maintain 90% self-sufficiency in refining. The report sees development of the domestic oil industry as globally competitive and helping safeguard India's assets. The capability of India's refineries, current upgrading, the newer refineries and plans for new projects are all mentioned

  6. Economic analyses of rapid population growth.

    Science.gov (United States)

    Birdsall, N

    1989-01-01

    "Discussion of the macroeconomic consequences of rapid population growth is organized into three schools: pessimists, optimists, and the recent revisionists. For the revisionists, differing views are presented about the pervasiveness and relevance of market failures, such as the negative externalities of childbearing, and about the ability of families and institutions to adjust rapidly to changes brought on by rapid population growth. A welfare economics approach is used to review the merits of various public policies to reduce fertility, including public financing of family planning services and taxes and incentives associated with childbearing." The focus is on developing countries. excerpt

  7. Organisational Factors of Rapid Growth of Slovenian Dynamic Enterprises

    Directory of Open Access Journals (Sweden)

    Pšeničny Viljem

    2013-01-01

    Full Text Available The authors provide key findings on the internal and external environmental factors of growth that affect the rapid growth of dynamic enterprises in relation to individual key organisational factors or functions. The key organisational relationships in a growing enterprise are upgraded with previous research findings and identified key factors of rapid growth through qualitative and quantitative analysis based on the analysis of 4,511 dynamic Slovenian enterprises exhibiting growth potential. More than 250 descriptive attributes of a sample of firms from 2011 were also used for further qualitative analysis and verification of key growth factors. On the basis of the sample (the study was conducted with 131 Slovenian dynamic enterprises, the authors verify whether these factors are the same as the factors that were studied in previous researches. They also provide empirical findings on rapid growth factors in relation to individual organisational functions: administration - management - implementation (entrepreneur - manager - employees. Through factor analysis they look for the correlation strength between individual variables (attributes that best describe each factor of rapid growth and that relate to the aforementioned organisational functions in dynamic enterprises. The research findings on rapid growth factors offer companies the opportunity to consider these factors during the planning and implementation phases of their business, to choose appropriate instruments for the transition from a small fast growing firm to a professionally managed growing company, to stimulate growth and to choose an appropriate growth strategy and organisational factors in order to remain, or become, dynamic enterprises that can further contribute to the preservation, growth and development of the Slovenian economy

  8. Multiple gingival pregnancy tumors with rapid growth

    Directory of Open Access Journals (Sweden)

    Wei-Lian Sun

    2014-09-01

    Full Text Available Pregnancy gingivitis is an acute form of gingivitis that affects pregnant women, with a prevalence of 30%, possibly ranging up to 100%. Sometimes, pregnancy gingivitis shows a tendency toward a localized hyperplasia called gingival pyogenic granuloma. Pregnancy tumor is a benign gingival hyperplasia with the gingiva as the most commonly involved site, but rarely it involves almost the entire gingiva. A 22-year-old woman was referred to our clinic with a chief complaint of gingival swelling that had lasted for 2 days. The lesions progressed rapidly and extensively, and almost all the gingiva was involved a week later. Generalized erythema, edema, hyperplasia, a hemorrhagic tendency, and several typical hemangiomatous masses were noted. Pregnancy was denied by the patient at the first and second visits, but was confirmed 2 weeks after the primary visit. The patient was given oral hygiene instructions. She recovered well, and the mass gradually regressed and had disappeared completely at the end of 12 weeks of pregnancy, without recurrence. The gingival lesions were finally diagnosed as multiple gingival pregnancy tumors. The patient delivered a healthy infant. An extensive and rapid growth of gingival pregnancy tumors during the early first month of pregnancy is a rare occurrence that is not familiar to dentists, gynecologists, and obstetricians. Those practitioners engaged in oral medicine and periodontology, primary care obstetrics, and gynecology should be aware of such gingival lesions to avoid misdiagnosis and overtreatment.

  9. Rapid Automated Mission Planning System, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed innovation is an automated UAS mission planning system that will rapidly identify emergency (contingency) landing sites, manage contingency routing, and...

  10. Rapid Robot Design Validation, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Energid Technologies will create a comprehensive software infrastructure for rapid validation of robot designs. The software will support push-button validation...

  11. Rapid Multiplex Microbial Detector, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — ORBITEC, in collaboration with Lucigen, proposes a rapid nucleic acid-based detector for spaceflight water systems to enable simultaneous quantification of multiple...

  12. A Rapid Coliform Detector, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — ORBITEC, in collaboration with Lucigen, proposes a rapid genetic detector for spaceflight water systems to enable real-time detection of E-coli with minimal...

  13. Grain nucleation and growth during phase transformations

    DEFF Research Database (Denmark)

    Offerman, S.E.; Dijk, N.H. van; Sietsma, J.

    2002-01-01

    of individual grains. Our measurements show that the activation energy for grain nucleation is at least two orders of magnitude smaller than that predicted by thermodynamic models. The observed growth curves of the newly formed grains confirm the parabolic growth model but also show three fundamentally...... different types of growth. Insight into the grain nucleation and growth mechanisms during phase transformations contributes to the development of materials with optimal mechanical properties....

  14. World pipeline work set for rapid growth

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    This paper reports on international pipeline construction which has entered a fast-growth period, accelerated by the new political and economic realities around the world and increasing demand for natural gas, crude oil and refined petroleum products. Many projects are under way or in planning for completion in the mid- to late 1990s in Europe, South America, Asia and the Middle East. Pipeline And Gas Journal's projection calls for construction or other work on 30,700 miles of new natural gas, crude oil and refined products pipelines in the 1992-93 period outside Canada and the U.S. These projects will cost an estimated $30 billion-plus. Natural gas pipelines will comprise most of the mileage, accounting for almost 23,000 miles at an estimated cost of $26.3 billion. Products pipelines, planned or under construction, will add another 5,800 miles at a cost of $2.8 billion. Crude oil pipelines, at a minimum, will total 1,900 new miles at a cost of slightly under $1 billion

  15. A metastable Mg11Sm phase obtained by rapid solidification

    International Nuclear Information System (INIS)

    Budurov, S.

    1993-01-01

    Molten Mg-Sm alloys with a Sm concentration of 4.93, 6.86, and 8.35 at.% were rapidly soldified with the aid of a shock wave gun device. Investigations of the obtained splats were performed with the aid of DSC, X-ray analysis, and metallography. Rapid soldification of the eutectic MgSm 8.35 alloy forms a new Im3m-type phase. (orig.)

  16. Rapid synthesis of single-phase bismuth ferrite by microwave-assisted hydrothermal method

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Wenqian [College of Materials Science and Engineering, China Jiliang University, 258 Xueyuan Street, Xiasha Higher Education District, Hangzhou 310018, Zhejiang Province (China); Chen, Zhi, E-mail: zchen0@gmail.com [College of Materials Science and Engineering, China Jiliang University, 258 Xueyuan Street, Xiasha Higher Education District, Hangzhou 310018, Zhejiang Province (China); Gao, Tong; Zhou, Dantong; Leng, Xiaonan; Niu, Feng [College of Materials Science and Engineering, China Jiliang University, 258 Xueyuan Street, Xiasha Higher Education District, Hangzhou 310018, Zhejiang Province (China); Zhu, Yuxiang [College of Materials Science and Engineering, China Jiliang University, 258 Xueyuan Street, Xiasha Higher Education District, Hangzhou 310018, Zhejiang Province (China); Tianjin Key Laboratory of Marine Resources and Chemistry, Tianjin University of Science and Technology, Tianjin (China); Qin, Laishun, E-mail: qinlaishun@yeah.net [College of Materials Science and Engineering, China Jiliang University, 258 Xueyuan Street, Xiasha Higher Education District, Hangzhou 310018, Zhejiang Province (China); Wang, Jiangying; Huang, Yuexiang [College of Materials Science and Engineering, China Jiliang University, 258 Xueyuan Street, Xiasha Higher Education District, Hangzhou 310018, Zhejiang Province (China)

    2016-06-01

    This paper describes on the fast synthesis of bismuth ferrite by the simple microwave-assisted hydrothermal method. The phase transformation and the preferred growth facets during the synthetic process have been investigated by X-ray diffraction. Bismuth ferrite can be quickly prepared by microwave hydrothermal method by simply controlling the reaction time, which is further confirmed by Fourier Transform infrared spectroscopy and magnetic measurement. - Graphical abstract: Single-phase BiFeO{sub 3} could be realized at a shortest reaction time of 65 min. The reaction time has strong influences on the phase transformation and the preferred growth facets. - Highlights: • Rapid synthesis (65 min) of BiFeO{sub 3} by microwave-assisted hydrothermal method. • Reaction time has influence on the purity and preferred growth facets. • FTIR and magnetic measurement further confirm the pure phase.

  17. Rapid synthesis of single-phase bismuth ferrite by microwave-assisted hydrothermal method

    International Nuclear Information System (INIS)

    Cao, Wenqian; Chen, Zhi; Gao, Tong; Zhou, Dantong; Leng, Xiaonan; Niu, Feng; Zhu, Yuxiang; Qin, Laishun; Wang, Jiangying; Huang, Yuexiang

    2016-01-01

    This paper describes on the fast synthesis of bismuth ferrite by the simple microwave-assisted hydrothermal method. The phase transformation and the preferred growth facets during the synthetic process have been investigated by X-ray diffraction. Bismuth ferrite can be quickly prepared by microwave hydrothermal method by simply controlling the reaction time, which is further confirmed by Fourier Transform infrared spectroscopy and magnetic measurement. - Graphical abstract: Single-phase BiFeO_3 could be realized at a shortest reaction time of 65 min. The reaction time has strong influences on the phase transformation and the preferred growth facets. - Highlights: • Rapid synthesis (65 min) of BiFeO_3 by microwave-assisted hydrothermal method. • Reaction time has influence on the purity and preferred growth facets. • FTIR and magnetic measurement further confirm the pure phase.

  18. Persistent Environmental Toxicants in Breast Milk and Rapid Infant Growth.

    Science.gov (United States)

    Criswell, Rachel; Lenters, Virissa; Mandal, Siddhartha; Stigum, Hein; Iszatt, Nina; Eggesbø, Merete

    2017-01-01

    Many environmental toxicants are passed to infants in utero and through breast milk. Exposure to toxicants during the perinatal period can alter growth patterns, impairing growth or increasing obesity risk. Previous studies have focused on only a few toxicants at a time, which may confound results. We investigated levels of 26 toxicants in breast milk and their associations with rapid infant growth, a risk factor for later obesity. We used data from the Norwegian HUMIS study, a multi-center cohort of 2,606 mothers and newborns enrolled between 2002 and 2008. Milk samples collected 1 month after delivery from a subset of 789 women oversampled by overweight were analyzed for toxicants including polychlorinated biphenyls (PCBs), heavy metals, and pesticides. Growth was defined as change in weight-for-age z-score between 0 and 6 months among the HUMIS population, and rapid growth was defined as change in z-score above 0.67. We used a Bayesian variable selection method to determine the exposures that most explained variation in the outcome. Identified toxicants were included in logistic and linear regression models to estimate associations with growth, adjusting for maternal age, smoking, education, pre-pregnancy body mass index (BMI), gestational weight gain, parity, child sex, cumulative breastfeeding, birth weight, gestational age, and preterm status. Of 789 infants, 19.2% displayed rapid growth. The median maternal age was 29.6 years, and the median pre-pregnancy BMI was 24.0 kg/m2, with 45.3% of mothers overweight or obese. Rapid growers were more likely to be firstborn. Hexachlorobenzene, β-hexachlorocyclohexane (β-HCH), and PCB-74 were identified in the variable selection method. An interquartile range (IQR) increase in β-HCH exposure was associated with a lower odds of rapid growth (OR 0.63, 95% CI 0.42-0.94). Newborns exposed to high levels of β-HCH showed reduced infant growth (β = -0.03, 95% CI -0.05 to -0.01 for IQR increase in breast milk concentration

  19. Economic Growth of a Rapidly Developing Economy: Theoretical Formulation

    Directory of Open Access Journals (Sweden)

    Oleg Sergeyevich Sukharev

    2016-06-01

    Full Text Available The subject matter of the article is the description of economic growth. Modern economy is characterized by a high rate of changes. These changes are the limiting parameters of modern development, which requires a modification of the basic models of growth, the substantiation of the expediency and necessity of a rapid development strategy. In a simple mathematical form, the statement of the problem of economic growth in the “green economy” is examined, in which the costs of environmental measures are not considered a priori as hampering economic development (as it is common for a number of modern neoclassical and neo-Keynesian growth models. The methodological basis of the article are the econometric approach and modelling method. The article has a theoretical character. The main hypothesis supposes that the rapid development strategy cannot make an adequate development strategy under certain conditions, but may be acceptable in other its specific conditions. In this sense, the important growth conditions are the availability of resources, the effectiveness of institutions and the current economic structure, the technological effectiveness of economy, as well as the conditions of technological development (“green economy” and the path of such development. In the article, on the theoretical level of analysis, the substantiation of the adequacy of the rapid development strategy for an economic system is given, whose goal is to achieve the standard of living of the countryleader. Based on the assumptions introduced, the period for which the rapid development strategy might be implemented and the economic lag of the country might be reduced from the country-leader is determined. The conditions that ensure the impact of innovations on the rate of economic development are summarized. The introduced range of dependencies and relations can be useful for the elaboration of the theory of innovation development and for the formation of a new

  20. Rapid in situ growth of oriented titanium-nickel oxide composite nanotubes arrays coated on a nitinol wire as a solid-phase microextraction fiber coupled to HPLC-UV.

    Science.gov (United States)

    Zhen, Qi; Zhang, Min; Song, Wenlan; Wang, Huiju; Wang, Xuemei; Du, Xinzhen

    2016-10-01

    An oriented titanium-nickel oxide composite nanotubes coating was in situ grown on a nitinol wire by direct electrochemical anodization in ethylene glycol with ammonium fluoride and water for the first time. The morphology and composition of the resulting coating showed that the anodized nitinol wire provided a titania-rich coating. The titanium-nickel oxide composite nanotubes coated fiber was used for solid-phase microextraction of different aromatic compounds coupled to high-performance liquid chromatography with UV detection. The titanium-nickel oxide composite nanotubes coating exhibited high extraction capability, good selectivity, and rapid mass transfer for weakly polar UV filters. Thereafter the important parameters affecting extraction efficiency were investigated for solid-phase microextraction of UV filters. Under the optimized conditions, the calibration curves were linear in the range of 0.1-300 μg/L for target UV filters with limits of detection of 0.019-0.082 μg/L. The intraday and interday precision of the proposed method with the single fiber were 5.3-7.2 and 5.9-7.9%, respectively, and the fiber-to-fiber reproducibility ranged from 6.3 to 8.9% for four fibers fabricated in different batches. Finally, its applicability was evaluated by the extraction and determination of target UV filters in environmental water samples. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Rapid growth, maturity, current problems, future prospects of NAA

    International Nuclear Information System (INIS)

    Guinn, V.P.

    2000-01-01

    The early rapid growth, the attainment of maturity, current problems, and future prospects of NAA (neutron activation analysis) are discussed, each in reasonable detail. In particular, the nature and causes of its current problems are examined, and suggestions are presented for the solution of these problems. The author believes that vigorous action in suggested areas of concentration can reinvigorate the status of NAA as an important method of elemental analysis. (author)

  2. Nanoparticle growth by particle-phase chemistry

    Science.gov (United States)

    Apsokardu, Michael J.; Johnston, Murray V.

    2018-02-01

    The ability of particle-phase chemistry to alter the molecular composition and enhance the growth rate of nanoparticles in the 2-100 nm diameter range is investigated through the use of a kinetic growth model. The molecular components included are sulfuric acid, ammonia, water, a non-volatile organic compound, and a semi-volatile organic compound. Molecular composition and growth rate are compared for particles that grow by partitioning alone vs. those that grow by a combination of partitioning and an accretion reaction in the particle phase between two organic molecules. Particle-phase chemistry causes a change in molecular composition that is particle diameter dependent, and when the reaction involves semi-volatile molecules, the particles grow faster than by partitioning alone. These effects are most pronounced for particles larger than about 20 nm in diameter. The modeling results provide a fundamental basis for understanding recent experimental measurements of the molecular composition of secondary organic aerosol showing that accretion reaction product formation increases linearly with increasing aerosol volume-to-surface-area. They also allow initial estimates of the reaction rate constants for these systems. For secondary aerosol produced by either OH oxidation of the cyclic dimethylsiloxane (D5) or ozonolysis of β-pinene, oligomerization rate constants on the order of 10-3 to 10-1 M-1 s-1 are needed to explain the experimental results. These values are consistent with previously measured rate constants for reactions of hydroperoxides and/or peroxyacids in the condensed phase.

  3. The rapid growth of OPEC′s domestic oil consumption

    International Nuclear Information System (INIS)

    Gately, Dermot; Al-Yousef, Nourah; Al-Sheikh, Hamad M.H.

    2013-01-01

    OPEC′s domestic oil consumption has increased seven-fold in 40 years, to 8.5 million barrels per day (mbd). They consume almost as much oil as China. This constitutes one-fourth of their production. Such rapid growth in consumption (5.1% annually, faster than their income growth of 3.1%) will challenge OPEC′s ability to increase their oil exports, which are relied upon in long-term world oil projections by the International Energy Agency (IEA), US Department of Energy (DOE/EIA) and British Petroleum (BP). However, these institutions assume unprecedented slowdowns in OPEC oil consumption – to less than 2% in the future – allowing them to project increases in OPEC oil exports with only modest increases in production. We analyze 1971–2010 data econometrically, with panel co-integration methods. We estimate that the income elasticity of consumption is about 1 for energy and oil. This means that OPEC′s energy and oil consumption will grow as rapidly as their income. Hence, continued high growth rates for domestic oil consumption are more likely than the unprecedented slowdowns projected by IEA, DOE/EIA and BP – adding an extra 6 mbd of OPEC consumption in 2030. This will have major implications for OPEC production and export levels, and for world oil prices. -- Highlights: •We analyze rapid growth of OPEC oil consumption (sevenfold since 1971: 5.1% annually). •Panel co-integration econometric estimate of income elasticity about 1.0. •Consensus projections (IEA, DOE/EIA) have consistently under projected OPEC consumption. •Future oil market implications if OPEC consumption grows as fast as income (as in past)

  4. Nanoparticle growth by particle-phase chemistry

    Directory of Open Access Journals (Sweden)

    M. J. Apsokardu

    2018-02-01

    Full Text Available The ability of particle-phase chemistry to alter the molecular composition and enhance the growth rate of nanoparticles in the 2–100 nm diameter range is investigated through the use of a kinetic growth model. The molecular components included are sulfuric acid, ammonia, water, a non-volatile organic compound, and a semi-volatile organic compound. Molecular composition and growth rate are compared for particles that grow by partitioning alone vs. those that grow by a combination of partitioning and an accretion reaction in the particle phase between two organic molecules. Particle-phase chemistry causes a change in molecular composition that is particle diameter dependent, and when the reaction involves semi-volatile molecules, the particles grow faster than by partitioning alone. These effects are most pronounced for particles larger than about 20 nm in diameter. The modeling results provide a fundamental basis for understanding recent experimental measurements of the molecular composition of secondary organic aerosol showing that accretion reaction product formation increases linearly with increasing aerosol volume-to-surface-area. They also allow initial estimates of the reaction rate constants for these systems. For secondary aerosol produced by either OH oxidation of the cyclic dimethylsiloxane (D5 or ozonolysis of β-pinene, oligomerization rate constants on the order of 10−3 to 10−1 M−1 s−1 are needed to explain the experimental results. These values are consistent with previously measured rate constants for reactions of hydroperoxides and/or peroxyacids in the condensed phase.

  5. Polygenic Risk, Rapid Childhood Growth, and the Development of Obesity

    Science.gov (United States)

    Belsky, Daniel W.; Moffitt, Terrie E.; Houts, Renate; Bennett, Gary G.; Biddle, Andrea K.; Blumenthal, James A.; Evans, James P.; Harrington, HonaLee; Sugden, Karen; Williams, Benjamin; Poulton, Richie; Caspi, Avshalom

    2012-01-01

    Objective To test how genomic loci identified in genome-wide association studies influence the development of obesity. Design A 38-year prospective longitudinal study of a representative birth cohort. Setting The Dunedin Multidisciplinary Health and Development Study, Dunedin, New Zealand. Participants One thousand thirty-seven male and female study members. Main Exposures We assessed genetic risk with a multilocus genetic risk score. The genetic risk score was composed of single-nucleotide polymorphisms identified in genome-wide association studies of obesity-related phenotypes. We assessed family history from parent body mass index data collected when study members were 11 years of age. Main Outcome Measures Body mass index growth curves, developmental phenotypes of obesity, and adult obesity outcomes were defined from anthropometric assessments at birth and at 12 subsequent in-person interviews through 38 years of age. Results Individuals with higher genetic risk scores were more likely to be chronically obese in adulthood. Genetic risk first manifested as rapid growth during early childhood. Genetic risk was unrelated to birth weight. After birth, children at higher genetic risk gained weight more rapidly and reached adiposity rebound earlier and at a higher body mass index. In turn, these developmental phenotypes predicted adult obesity, mediating about half the genetic effect on adult obesity risk. Genetic associations with growth and obesity risk were independent of family history, indicating that the genetic risk score could provide novel information to clinicians. Conclusions Genetic variation linked with obesity risk operates, in part, through accelerating growth in the early childhood years after birth. Etiological research and prevention strategies should target early childhood to address the obesity epidemic. PMID:22665028

  6. Uncooled infrared sensors: rapid growth and future perspective

    Science.gov (United States)

    Balcerak, Raymond S.

    2000-07-01

    The uncooled infrared cameras are now available for both the military and commercial markets. The current camera technology incorporates the fruits of many years of development, focusing on the details of pixel design, novel material processing, and low noise read-out electronics. The rapid insertion of cameras into systems is testimony to the successful completion of this 'first phase' of development. In the military market, the first uncooled infrared cameras will be used for weapon sights, driver's viewers and helmet mounted cameras. Major commercial applications include night driving, security, police and fire fighting, and thermography, primarily for preventive maintenance and process control. The technology for the next generation of cameras is even more demanding, but within reach. The paper outlines the technology program planned for the next generation of cameras, and the approaches to further enhance performance, even to the radiation limit of thermal detectors.

  7. Growth medium for the rapid isolation and identification of anthrax

    Science.gov (United States)

    Kiel, Johnathan L.; Parker, Jill E.; Grubbs, Teri R.; Alls, John L.

    2000-07-01

    Anthrax has been recognized as a highly likely biological warfare or terrorist agent. The purpose of this work was to design a culture technique to rapidly isolate and identify `live' anthrax. In liquid or solid media form, 3AT medium (3-amino-L-tyrosine, the main ingredient) accelerated germination and growth of anthrax spores in 5 to 6 hours to a point expected at 18 to 24 hours with ordinary medium. During accelerated growth, standard definitive diagnostic tests such as sensitivity to lysis by penicillin or bacteriophage can be run. During this time, the bacteria synthesized a fluorescent and thermochemiluminescent polymer. Bacteria captured by specific antibody are, therefore, already labeled. Because living bacteria are required to generate the polymer, the test converts immunoassays for anthrax into viability assays. Furthermore, the polymer formation leads to the death of the vegetative form and non-viability of the spores produced in the medium. By altering the formulation of the medium, other microbes and even animal and human cells can be grown in it and labeled (including viruses grown in the animal or human cells).

  8. Growth perturbations in a phenotype with rapid fetal growth preceding preterm labor and term birth.

    Science.gov (United States)

    Lampl, Michelle; Kusanovic, Juan Pedro; Erez, Offer; Gotsch, Francesca; Espinoza, Jimmy; Goncalves, Luis; Lee, Wesley; Gomez, Ricardo; Nien, Jyh Kae; Frongillo, Edward A; Romero, Roberto

    2009-01-01

    The variability in fetal growth rates and gestation duration in humans is not well understood. Of interest are women presenting with an episode of preterm labor and subsequently delivering a term neonate, who is small relative to peers of similar gestational age. To further understand these relationships, fetal growth patterns predating an episode of preterm labor were investigated. Retrospective analysis of fetal biometry assessed by serial ultrasound in a prospectively studied sample of pregnancies in Santiago, Chile, tested the hypothesis that fetal growth patterns among uncomplicated pregnancies (n = 3,706) and those with an episode of preterm labor followed by term delivery (n = 184) were identical across the time intervals 16-22 weeks, 22-28 weeks, and 28-34 weeks in a multilevel mixed-effects regression. The hypothesis was not supported. Fetal weight growth rate was faster from 16 weeks among pregnancies with an episode of preterm labor (P < 0.05), declined across midgestation (22-28 weeks, P < 0.05), and rebounded between 28 and 34 weeks (P = 0.06). This was associated with perturbations in abdominal circumference growth and proportionately larger biparietal diameter from 22 gestational weeks (P = 0.03), greater femur (P = 0.01), biparietal diameter (P = 0.001) and head circumference (P = 0.02) dimensions relative to abdominal circumference across midgestation (22-28 weeks), followed by proportionately smaller femur diaphyseal length (P = 0.02) and biparietal diameter (P = 0.03) subsequently. A distinctive rapid growth phenotype characterized fetal growth preceding an episode of preterm labor among this sample of term-delivered neonates. Perturbations in abdominal circumference growth and patterns of proportionality suggest an altered growth strategy pre-dating the preterm labor episode.

  9. Phase field modeling of rapid crystallization in the phase-change material AIST

    Science.gov (United States)

    Tabatabaei, Fatemeh; Boussinot, Guillaume; Spatschek, Robert; Brener, Efim A.; Apel, Markus

    2017-07-01

    We carry out phase field modeling as a continuum simulation technique in order to study rapid crystallization processes in the phase-change material AIST (Ag4In3Sb67Te26). In particular, we simulate the spatio-temporal evolution of the crystallization of a molten area of the phase-change material embedded in a layer stack. The simulation model is adapted to the experimental conditions used for recent measurements of crystallization rates by a laser pulse technique. Simulations are performed for substrate temperatures close to the melting temperature of AIST down to low temperatures when an amorphous state is involved. The design of the phase field model using the thin interface limit allows us to retrieve the two limiting regimes of interface controlled (low temperatures) and thermal transport controlled (high temperatures) dynamics. Our simulations show that, generically, the crystallization velocity presents a maximum in the intermediate regime where both the interface mobility and the thermal transport, through the molten area as well as through the layer stack, are important. Simulations reveal the complex interplay of all different contributions. This suggests that the maximum switching velocity depends not only on material properties but also on the precise design of the thin film structure into which the phase-change material is embedded.

  10. Phase evolution and dendrite growth in laser cladding of aluminium on zirconium

    International Nuclear Information System (INIS)

    Yue, T.M.; Xie, H.; Lin, X.; Yang, H.O.

    2011-01-01

    Research highlights: → Laser cladding of Al on pure Zr. → A series of phase evolutions occurred across the laser-clad coating. → Epitaxial crystal growth, backward dendrite growth and two-phase eutectic dendritic growth. → Phase and microstructure evolution is discussed. - Abstract: Aluminium was laser clad on a pure zirconium substrate using the blown powder method. The microstructure across the laser-clad coating was studied. Starting from the bottom to the top surface of the coating, a series of phase evolutions had occurred: (Zr) → (Zr) + AlZr 2 + AlZr 3 → Al 4 Zr 5 + Al 3 Zr 2 → Al 3 Zr 2 + AlZr 2 → Al 2 Zr → Al 2 Zr + Al 3 Zr. This resulted in an epitaxial columnar crystal growth at the re-melt substrate boundary, a band of backward growth Al 3 Zr 2 dendrites towards the lower half of the coating, and a two-phase eutectic dendritic growth of Al 2 Zr + Al 3 Zr towards the top of the coating. The evolution of the various phases and microstructures is discussed in conjunction with the Al-Zr phase diagram, the criteria for planar interface instability, and the theory of eutectic growth under rapid solidification conditions (the TMK model).

  11. Rapid Population Growth-Cause or Result of Global Problems?

    Science.gov (United States)

    Schwartz, Richard H.

    Explosive population growth is a symptom of the world's unjust and inequitable social, political, and economic conditions. The current rate of growth is staggering, particularly in the cities of the underdeveloped countries. While some progress has been made in slowing population growth, several factors still contribute to its momentum. One of…

  12. Phase-field model of eutectic growth

    International Nuclear Information System (INIS)

    Karma, A.

    1994-01-01

    A phase-field model which describes the solidification of a binary eutectic alloy with a simple symmetric phase diagram is introduced and the sharp-interface limit of this model is explored both analytically and numerically

  13. Nitrogen controlled iron catalyst phase during carbon nanotube growth

    Energy Technology Data Exchange (ETDEWEB)

    Bayer, Bernhard C., E-mail: bernhard.bayer@univie.ac.at [Department of Engineering, University of Cambridge, Cambridge CB3 0FA (United Kingdom); Faculty of Physics, University of Vienna, A-1090 Vienna (Austria); Baehtz, Carsten [Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, D-01314 Dresden (Germany); Kidambi, Piran R.; Weatherup, Robert S.; Caneva, Sabina; Cabrero-Vilatela, Andrea; Hofmann, Stephan [Department of Engineering, University of Cambridge, Cambridge CB3 0FA (United Kingdom); Mangler, Clemens; Kotakoski, Jani; Meyer, Jannik C. [Faculty of Physics, University of Vienna, A-1090 Vienna (Austria); Goddard, Caroline J. L. [Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB3 0FS (United Kingdom)

    2014-10-06

    Close control over the active catalyst phase and hence carbon nanotube structure remains challenging in catalytic chemical vapor deposition since multiple competing active catalyst phases typically co-exist under realistic synthesis conditions. Here, using in-situ X-ray diffractometry, we show that the phase of supported iron catalyst particles can be reliably controlled via the addition of NH{sub 3} during nanotube synthesis. Unlike polydisperse catalyst phase mixtures during H{sub 2} diluted nanotube growth, nitrogen addition controllably leads to phase-pure γ-Fe during pre-treatment and to phase-pure Fe{sub 3}C during growth. We rationalize these findings in the context of ternary Fe-C-N phase diagram calculations and, thus, highlight the use of pre-treatment- and add-gases as a key parameter towards controlled carbon nanotube growth.

  14. AN ANALYSIS OF THE RAPID GROWTH FACTORS PRESENTED IN THE LITERATURE OF THE FIELD

    Directory of Open Access Journals (Sweden)

    ALB MARIA

    2015-03-01

    Full Text Available This paper presents the main rapid growth factors, as encountered in literature and discusses the importance and contribution of these factors in achieving the rapid growth, respectively if this growth phenomenon may be achieved in the absence of the aforesaid factors. The paper examines the factors and subfactors considered or found by scholars to have an effect on or be in connection with the rapid growth. A comparative analysis was performed on several studies concerning the rapid growth companies. Among the main factors influencing the rapid growth are those related to the human resources management, the entrepreneur characteritics and the characteristics of the business. The paper also discusses several issues related to the will of the manager or the entrepreneur, repectively the need to understand the role of the factors that intervene when the growth is not wanted and still obtained or when the growth is targeted but not achieved. The conclusion is in agreement with other scholars’ findings reported in the literature. Certain factors correlated with the appropriate actions may lead to the rapid growth. The paper represents a starting point for the study of those management related aspects enabling companies to grow rapidly in the Romanian business environment.

  15. Rapid In-Place Composite Rotor Damage Detection, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Luna Innovations is proposing to further develop the Rapid In-Place Composite Rotor Damage Detection (RIPCoRDD) System for determining and tracking the structural...

  16. Rapid In-Place Composite Rotor Damage Detection, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Luna Innovations is proposing to develop the Rapid In-Place Composite Rotor Damage Detection (RIPCoRDD) for determining and tracking the structural health of...

  17. Persistent Environmental Toxicants in Breast Milk and Rapid Infant Growth

    NARCIS (Netherlands)

    Criswell, Rachel; Lenters, Virissa; Mandal, Siddhartha; Stigum, Hein; Iszatt, Nina; Eggesbø, Merete

    2017-01-01

    BACKGROUND/AIMS: Many environmental toxicants are passed to infants in utero and through breast milk. Exposure to toxicants during the perinatal period can alter growth patterns, impairing growth or increasing obesity risk. Previous studies have focused on only a few toxicants at a time, which may

  18. Heliopause Electrostatic Rapid Transit System (HERTS) (Phase II)

    Data.gov (United States)

    National Aeronautics and Space Administration — Our proposal builds upon our teams technical findings in Phase 1 - that an E-Sail propelled spacecraft can travel 100 AU in less than 10 years or to the Heliopause...

  19. Communication and The Challenges of Rapid Population Growth in ...

    African Journals Online (AJOL)

    2005) which projected the African Population at 1,349 million by 2025 and 1,969 million by 2050. These figures are so frightening that the use of communication to contribute to checking the high population growth is challenged. We discuss ...

  20. Phase lock of rapid cycling synchrotron and neutron choppers

    International Nuclear Information System (INIS)

    Praeg, W.; McGhee, D.; Volk, G.

    1981-01-01

    The 500-MeV synchrotron of Argonne's Intense Pulsed Neutron Source operates at 30 Hz. Its beam spill must be locked to neutron choppers with a precision of +- 0.5 μs. A chopper and an accelerator have large and different inertias. This makes synchronization by phase lock to the 60-Hz power line extremely difficult. We solved the phasing problems by running both the Ring Magnet Power Supply (RMPS) of the synchrotron and the chopper motors from a common oscillator that is stable to 1 ppM and by controlling five quantities of the RMPS. The quantities controlled by feedback loops are dc current, injection current, ejection current, resonant frequency, and the phase shift between the synchrotron peak field and the chopper window

  1. Activity of toluene-degrading Pseudomonas putida in the early growth phase of a biofilm for waste gas treatment

    DEFF Research Database (Denmark)

    Pedersen, A.R.; Møller, S.; Molin, S.

    1997-01-01

    A biological trickling filter for treatment of toluene-containing waste gas was studied. The overall kinetics of the biofilm growth was followed in the early growth phase. A rapid initial colonization took place during the first three days. The biofilm thickness increased exponentially, whereas...

  2. Regulatory design governing progression of population growth phases in bacteria.

    Directory of Open Access Journals (Sweden)

    Agustino Martínez-Antonio

    Full Text Available It has long been noted that batch cultures inoculated with resting bacteria exhibit a progression of growth phases traditionally labeled lag, exponential, pre-stationary and stationary. However, a detailed molecular description of the mechanisms controlling the transitions between these phases is lacking. A core circuit, formed by a subset of regulatory interactions involving five global transcription factors (FIS, HNS, IHF, RpoS and GadX, has been identified by correlating information from the well- established transcriptional regulatory network of Escherichia coli and genome-wide expression data from cultures in these different growth phases. We propose a functional role for this circuit in controlling progression through these phases. Two alternative hypotheses for controlling the transition between the growth phases are first, a continuous graded adjustment to changing environmental conditions, and second, a discontinuous hysteretic switch at critical thresholds between growth phases. We formulate a simple mathematical model of the core circuit, consisting of differential equations based on the power-law formalism, and show by mathematical and computer-assisted analysis that there are critical conditions among the parameters of the model that can lead to hysteretic switch behavior, which--if validated experimentally--would suggest that the transitions between different growth phases might be analogous to cellular differentiation. Based on these provocative results, we propose experiments to test the alternative hypotheses.

  3. Regulatory design governing progression of population growth phases in bacteria.

    Science.gov (United States)

    Martínez-Antonio, Agustino; Lomnitz, Jason G; Sandoval, Santiago; Aldana, Maximino; Savageau, Michael A

    2012-01-01

    It has long been noted that batch cultures inoculated with resting bacteria exhibit a progression of growth phases traditionally labeled lag, exponential, pre-stationary and stationary. However, a detailed molecular description of the mechanisms controlling the transitions between these phases is lacking. A core circuit, formed by a subset of regulatory interactions involving five global transcription factors (FIS, HNS, IHF, RpoS and GadX), has been identified by correlating information from the well- established transcriptional regulatory network of Escherichia coli and genome-wide expression data from cultures in these different growth phases. We propose a functional role for this circuit in controlling progression through these phases. Two alternative hypotheses for controlling the transition between the growth phases are first, a continuous graded adjustment to changing environmental conditions, and second, a discontinuous hysteretic switch at critical thresholds between growth phases. We formulate a simple mathematical model of the core circuit, consisting of differential equations based on the power-law formalism, and show by mathematical and computer-assisted analysis that there are critical conditions among the parameters of the model that can lead to hysteretic switch behavior, which--if validated experimentally--would suggest that the transitions between different growth phases might be analogous to cellular differentiation. Based on these provocative results, we propose experiments to test the alternative hypotheses.

  4. Phase-field crystal simulation facet and branch crystal growth

    Science.gov (United States)

    Chen, Zhi; Wang, Zhaoyang; Gu, Xinrui; Chen, Yufei; Hao, Limei; de Wit, Jos; Jin, Kexin

    2018-05-01

    Phase-field crystal model with one mode is introduced to describe morphological transition. The relationship between growth morphology and smooth density distribution was investigated. The results indicate that the pattern selection of dendrite growth is caused by the competition between interface energy anisotropy and interface kinetic anisotropy based on the 2D phase diagram. When the calculation time increases, the crystal grows to secondary dendrite at the dimensionless undercooling equal to - 0.4. Moreover, when noise is introduced in the growth progress, the symmetry is broken in the growth mode, and there becomes irregular fractal-like growth morphology. Furthermore, the single crystal shape develops into polycrystalline when the noise amplitude is large enough. When the dimensionless undercooling is less than - 0.3, the noise has a significant effect on the growth shape. In addition, the growth velocity of crystal near to liquid phase line is slow, while the shape far away from the liquid adapts to fast growth. Based on the simulation results, the method was proved to be effective, and it can easily obtain different crystal shapes by choosing the different points in 2D phase diagram.

  5. Gradient microfluidics enables rapid bacterial growth inhibition testing.

    Science.gov (United States)

    Li, Bing; Qiu, Yong; Glidle, Andrew; McIlvenna, David; Luo, Qian; Cooper, Jon; Shi, Han-Chang; Yin, Huabing

    2014-03-18

    Bacterial growth inhibition tests have become a standard measure of the adverse effects of inhibitors for a wide range of applications, such as toxicity testing in the medical and environmental sciences. However, conventional well-plate formats for these tests are laborious and provide limited information (often being restricted to an end-point assay). In this study, we have developed a microfluidic system that enables fast quantification of the effect of an inhibitor on bacteria growth and survival, within a single experiment. This format offers a unique combination of advantages, including long-term continuous flow culture, generation of concentration gradients, and single cell morphology tracking. Using Escherichia coli and the inhibitor amoxicillin as one model system, we show excellent agreement between an on-chip single cell-based assay and conventional methods to obtain quantitative measures of antibiotic inhibition (for example, minimum inhibition concentration). Furthermore, we show that our methods can provide additional information, over and above that of the standard well-plate assay, including kinetic information on growth inhibition and measurements of bacterial morphological dynamics over a wide range of inhibitor concentrations. Finally, using a second model system, we show that this chip-based systems does not require the bacteria to be labeled and is well suited for the study of naturally occurring species. We illustrate this using Nitrosomonas europaea, an environmentally important bacteria, and show that the chip system can lead to a significant reduction in the period required for growth and inhibition measurements (<4 days, compared to weeks in a culture flask).

  6. Rapid population growth and environmental degradation: ultimate versus proximate factors.

    Science.gov (United States)

    Shaw, R P

    1989-01-01

    This philosophical review of 2 arguments about responsibility for and solutions to environmental degradation concludes that both sides are correct: the ultimate and the proximal causes. Ultimate causes of pollution are defined as the technology responsible for a given type of pollution, such as burning fossil fuel; proximate causes are defined as situation-specific factors confounding the problem, such as population density or rate of growth. Commoner and others argue that developed countries with low or negative population growth rates are responsible for 80% of world pollution, primarily in polluting technologies such as automobiles, power generation, plastics, pesticides, toxic wastes, garbage, warfaring, and nuclear weapons wastes. Distortionary policies also contribute; examples are agricultural trade protection, land mismanagement, urban bias in expenditures, and institutional rigidity., Poor nations are responsible for very little pollution because poverty allows little waste or expenditures for polluting, synthetic technologies. The proximal causes of pollution include numbers and rate of growth of populations responsible for the pollution. Since change in the ultimate cause of pollution remains out of reach, altering the numbers of polluters can make a difference. Predictions are made for proportions of the world's total waste production, assuming current 1.6 tons/capita for developed countries and 0.17 tons/capita for developing countries. If developing countries grow at current rates and become more wealthy, they will be emitting half the world's waste by 2025. ON the other hand, unsustainable population growth goes along with inadequate investment in human capital: education, health, employment, infrastructure. The solution is to improve farming technologies in the 117 non-self-sufficient countries, fund development in the most unsustainable enclaves of growing countries, break institutionalized socio-political rigidity in these enclaves, and focus on

  7. Crystal growth within a phase change memory cell.

    Science.gov (United States)

    Sebastian, Abu; Le Gallo, Manuel; Krebs, Daniel

    2014-07-07

    In spite of the prominent role played by phase change materials in information technology, a detailed understanding of the central property of such materials, namely the phase change mechanism, is still lacking mostly because of difficulties associated with experimental measurements. Here, we measure the crystal growth velocity of a phase change material at both the nanometre length and the nanosecond timescale using phase-change memory cells. The material is studied in the technologically relevant melt-quenched phase and directly in the environment in which the phase change material is going to be used in the application. We present a consistent description of the temperature dependence of the crystal growth velocity in the glass and the super-cooled liquid up to the melting temperature.

  8. Mechanical model for filament buckling and growth by phase ordering.

    Science.gov (United States)

    Rey, Alejandro D; Abukhdeir, Nasser M

    2008-02-05

    A mechanical model of open filament shape and growth driven by phase ordering is formulated. For a given phase-ordering driving force, the model output is the filament shape evolution and the filament end-point kinematics. The linearized model for the slope of the filament is the Cahn-Hilliard model of spinodal decomposition, where the buckling corresponds to concentration fluctuations. Two modes are predicted: (i) sequential growth and buckling and (ii) simultaneous buckling and growth. The relation among the maximum buckling rate, filament tension, and matrix viscosity is given. These results contribute to ongoing work in smectic A filament buckling.

  9. Phase field simulation of grain growth in porous uranium dioxide

    International Nuclear Information System (INIS)

    Ahmed, Karim; Pakarinen, Janne; Allen, Todd; El-Azab, Anter

    2014-01-01

    Graphical abstract: Display Omitted -- Abstract: A novel phase field model has been developed to investigate grain growth in porous polycrystalline UO 2 . Based on a system of Cahn–Hilliard and Allen–Cahn equations, the model takes into consideration both the curvature driven grain boundary motion and pore migration by surface diffusion. As such, the model accounts for the interaction between pore and grain boundary kinetics, which tends to retard the growth process. The phase field model parameters are found in terms of measurable material properties. Hence, quantitative results that can be compared with experiments were obtained. The model has been used to investigate the effect of porosity on the kinetics of grain growth in UO 2 . It is found that, as the amount of porosity increases, grain growth in UO 2 gradually changes from boundary controlled growth to pore controlled growth. For high porosity levels, the grain growth completely stops after a short evolution time. It is also found that the inhomogeneous distribution of pores leads to abnormal grain growth even without taking into account the anisotropy in grain boundary energy and mobility. The effects of porosity, temperature and initial microstructure on grain growth were thoroughly investigated. The model predictions are in good agreement with published experimental results of grain growth in UO 2

  10. Linearized FUN3D for Rapid Aeroelastic and Aeroservoelastic Design and Analysis, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The overall objective of this Phase I project is to develop a hybrid approach in FUN3D, referred herein to as the Linearized FUN3D, for rapid aeroelastic and...

  11. Coordinated Control of Multi-Agent Systems in Rapidly Varying Environments, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The main objective of this Phase II STTR project is to develop advanced control algorithms that enable multiple autonomous agents to perform complex tasks in rapidly...

  12. Rapid compression induced solidification of two amorphous phases of poly(ethylene terephthalate)

    Energy Technology Data Exchange (ETDEWEB)

    Hong, S M [Laboratory of High Pressure Physics, Southwest Jiaotong University, Chengdu, 610031 (China); Liu, X R [Laboratory of High Pressure Physics, Southwest Jiaotong University, Chengdu, 610031 (China); Su, L [Laboratory of High Pressure Physics, Southwest Jiaotong University, Chengdu, 610031 (China); Huang, D H [Laboratory of High Pressure Physics, Southwest Jiaotong University, Chengdu, 610031 (China); Li, L B [Foods Research Centre Unilever R and D, Vlaardingen Olivier van Noortlaan, 120, 3133 AT Vlaardingen (Netherlands)

    2006-08-21

    Melts of poly(ethylene terephthalate) were solidified by rapid compression to 2 GPa within 20 ms and by a series of comparative processes including natural cooling, slow compressing and rapid cooling, respectively. By combining XRD and differential scanning calorimetry data of the recovered samples, it is made clear that rapid compression induces two kinds of amorphous phases. One is relatively stable and can also be formed in the slow compression and the cooling processes. Another is metastable and transforms to crystalline phase at 371 K. This metastable amorphous phase cannot be obtained by slow compression or natural cooling, and its crystallization temperature is remarkably different from that of the metastable amorphous phase formed in the rapid cooling sample.

  13. NADPH promotes the rapid growth of the tumor

    Directory of Open Access Journals (Sweden)

    Hao Sheng

    2018-04-01

    Full Text Available NADPH oxidase is the main source of intracellular reactive oxygen species (ROS. ROS plays an important role in a variety of tumor types. The ROS mediated by NADPH oxidase increases the expression of hypoxia-inducible factor alpha (HIF-α through multiple signaling pathways in tumor, and HIF-α could be regulated and controlled by downstream multiple targeted genes such as vascular endothelial growth factor, glucose transporter to promote tumor angiogenesis, cell energy metabolism reprogram and tumor metastasis. Meanwhile, HIF-α can also regulate the expression of NADPH oxidase by ROS, thus further promoting development of tumor. In this review, we summarized the functions of NADPH in tumorigenesis and discussed their potential implications in cancer therapy.

  14. A low cost rapid prototype platform for a three phase PFC rectifier application

    DEFF Research Database (Denmark)

    Haase, Frerk; Kouchaki, Alireza; Nymand, Morten

    2015-01-01

    In this paper the design and development of a low cost rapid prototype platform for a Three Phase PFC rectifier application is presented. The active rectifier consists of a SiC-MOSFET based PWM converter and a low cost rapid prototype platform for simulating and implementing the digital control...

  15. Armenia; The Road to Sustained Rapid Growth-Cross-Country Evidence

    OpenAIRE

    Garbis Iradian

    2003-01-01

    This study examines the growth determinants and the economic policy challenges that Armenia faces to sustain the rapid growth of the past two years. The paper also seeks to answer the following two questions: Why has Armenia performed relatively better than other transition economies? What are the roles of macroeconomic policies and the level of financial intermediation in explaining growth differences? The paper also draws upon past cross-country experiences by estimating panel regressions o...

  16. Rapid hydrogen hydrate growth from non-stoichiometric tuning mixtures during liquid nitrogen quenching.

    Science.gov (United States)

    Grim, R Gary; Kerkar, Prasad B; Sloan, E Dendy; Koh, Carolyn A; Sum, Amadeu K

    2012-06-21

    In this study the rapid growth of sII H(2) hydrate within 20 min of post formation quenching towards liquid nitrogen (LN(2)) temperature is presented. Initially at 72 MPa and 258 K, hydrate samples would cool to the conditions of ~60 MPa and ~90 K after quenching. Although within the stability region for H(2) hydrate, new hydrate growth only occurred under LN(2) quenching of the samples when preformed hydrate "seeds" of THF + H(2) were in the presence of unconverted ice. The characterization of hydrate seeds and the post-quenched samples was performed with confocal Raman spectroscopy. These results suggest that quenching to LN(2) temperature, a common preservation technique for ex situ hydrate analysis, can lead to rapid unintended hydrate growth. Specifically, guest such as H(2) that may otherwise need sufficiently long induction periods to nucleate, may still experience rapid growth through an increased kinetic effect from a preformed hydrate template.

  17. Rapid Urban Growth and Land Use Patterns in Doha, Qatar: Opportunities for Sustainability?

    Directory of Open Access Journals (Sweden)

    Vivek Shandas

    2017-06-01

    Full Text Available Amidst chaotic growth of Asian cities, the expansion of urban infrastructure in the Middle East's Gulf region is arguably outpacing any other region on the planet. Yet we have a limited understanding of the types of urban form or the extent to which this rapid urbanization is giving rise to sustainable patterns of growth. We ask, what is the pace and character of urban growth in one Middle East city, Doha, Qatar. By using remotely sensed imagery from 1987 to 2013, we examined the pace, quality, and characteristics of urban growth. We further use the results to create a typology of urban growth that integrates historical and spatial dimensions for describing the qualitative aspects of growth and its implications on regional landscapes. Our results suggest that Doha is creating development patterns similar to many Western cities, and that planners may need to consider whether the emerging urban form offers opportunities for more sustainable growth in the future.

  18. Growth of high purity semiconductor epitaxial layers by liquid phase ...

    Indian Academy of Sciences (India)

    Unknown

    semiconductor materials in high purity form by liquid phase epitaxy (LPE) technique. Various possible sources of impurities in such ... reference to the growth of GaAs layers. The technique of growing very high purity layers ... the inner walls of the gas lines and (e) the containers for storing, handling and cleaning of the mate-.

  19. Phase field simulations of ice crystal growth in sugar solutions

    NARCIS (Netherlands)

    Sman, Van Der R.G.M.

    2016-01-01

    We present the first model ever, that describes explicitly ice crystal growth in a sugar solution during freezing. This 2-D model uses the phase field method, supplemented with realistic, and predictive theories on the thermodynamics and (diffusion) kinetics of this food system. We have to make

  20. Growth of cadmium zinc telluride by liquid phase electroepitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Armour, N.; Dost, S. [Crystal Growth Laboratory, Faculty of Engineering, University of Victoria, Victoria BC, V8W 3P6 (Canada); Sheibani, H. [Department of Industrial Engineering, Alhosn University, Abu Dhabi (United Arab Emirates)

    2006-10-15

    This study was undertaken to examine the feasibility of growing CdZnTe by liquid phase electroepitaxy. Based on our successful LPEE system of GaInAs, a new crucible to grow CdZnTe was developed. The development presented numerous difficulties. The physical properties of CdZnTe make this material very difficult to grow. All components of the system were investigated. Electromigration of the solute across the solution carries species towards the growth interface. In liquid Cd-Zn-Te, the CdTe and ZnTe species remain associated, contrary to the GaInAs system. Experiments showed that LPEE growth of CdZnTe is possible and the electromigration mechanism functions well in the CdZnTe solution. Despite this, other problems remained with the new LPEE system. The preparation of the solution proved difficult without pressurizing the LPEE crucible. Control of the reaction required the use of pre-compounded CdTe and ZnTe. Proper control of the solution saturation is imperative to ensure minimal dissolution of the seed prior to growth initiation and a reasonable growth rate during growth. The solution remained an issue during the duration of growth due to the high vapor pressures of the constituents. Tellurium evaporation during growth could lower solution volume until electrical contact across the solution is broken. Careful preparation of appropriate solution volume was imperative for successful growth. In LPEE, a uniform electric current passage across the growth interface is necessary for uniform and stable growth interface. This requires the design of a uniform contact zone between the bottom graphite electrode and the seed crystal. The contact zone issue was not adequately resolved in this study. However, a number of successful growth runs were achieved despite the electrical contact problems. Results show that the LPEE of growth CdZnTe is feasible. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  1. Growth of cadmium zinc telluride by liquid phase electroepitaxy

    International Nuclear Information System (INIS)

    Armour, N.; Dost, S.; Sheibani, H.

    2006-01-01

    This study was undertaken to examine the feasibility of growing CdZnTe by liquid phase electroepitaxy. Based on our successful LPEE system of GaInAs, a new crucible to grow CdZnTe was developed. The development presented numerous difficulties. The physical properties of CdZnTe make this material very difficult to grow. All components of the system were investigated. Electromigration of the solute across the solution carries species towards the growth interface. In liquid Cd-Zn-Te, the CdTe and ZnTe species remain associated, contrary to the GaInAs system. Experiments showed that LPEE growth of CdZnTe is possible and the electromigration mechanism functions well in the CdZnTe solution. Despite this, other problems remained with the new LPEE system. The preparation of the solution proved difficult without pressurizing the LPEE crucible. Control of the reaction required the use of pre-compounded CdTe and ZnTe. Proper control of the solution saturation is imperative to ensure minimal dissolution of the seed prior to growth initiation and a reasonable growth rate during growth. The solution remained an issue during the duration of growth due to the high vapor pressures of the constituents. Tellurium evaporation during growth could lower solution volume until electrical contact across the solution is broken. Careful preparation of appropriate solution volume was imperative for successful growth. In LPEE, a uniform electric current passage across the growth interface is necessary for uniform and stable growth interface. This requires the design of a uniform contact zone between the bottom graphite electrode and the seed crystal. The contact zone issue was not adequately resolved in this study. However, a number of successful growth runs were achieved despite the electrical contact problems. Results show that the LPEE of growth CdZnTe is feasible. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  2. Disorder trapping by rapidly moving phase interface in an undercooled liquid

    Science.gov (United States)

    Galenko, Peter; Danilov, Denis; Nizovtseva, Irina; Reuther, Klemens; Rettenmayr, Markus

    2017-08-01

    Non-equilibrium phenomena such as the disappearance of solute drag, the origin of solute trapping and evolution of disorder trapping occur during fast transformations with originating metastable phases [D.M. Herlach, P.K. Galenko, D. Holland-Moritz, Metastable solids from undrercooled melts (Elsevier, Amsterdam, 2007)]. In the present work, a theoretical investigation of disorder trapping by a rapidly moving phase interface is presented. Using a model of fast phase transformations, a system of governing equations for the diffusion of atoms, and the evolution of both long-range order parameter and phase field variable is formulated. First numerical solutions are carried out for a congruently melting binary alloy system.

  3. Phase-field model of vapor-liquid-solid nanowire growth

    Science.gov (United States)

    Wang, Nan; Upmanyu, Moneesh; Karma, Alain

    2018-03-01

    We present a multiphase-field model to describe quantitatively nanowire growth by the vapor-liquid-solid (VLS) process. The free-energy functional of this model depends on three nonconserved order parameters that distinguish the vapor, liquid, and solid phases and describe the energetic properties of various interfaces, including arbitrary forms of anisotropic γ plots for the solid-vapor and solid-liquid interfaces. The evolution equations for those order parameters describe basic kinetic processes including the rapid (quasi-instantaneous) equilibration of the liquid catalyst to a droplet shape with constant mean curvature, the slow incorporation of growth atoms at the droplet surface, and crystallization within the droplet. The standard constraint that the sum of the phase fields equals unity and the conservation of the number of catalyst atoms, which relates the catalyst volume to the concentration of growth atoms inside the droplet, are handled via separate Lagrange multipliers. An analysis of the model is presented that rigorously maps the phase-field equations to a desired set of sharp-interface equations for the evolution of the phase boundaries under the constraint of force balance at three-phase junctions (triple points) given by the Young-Herring relation that includes torque term related to the anisotropy of the solid-liquid and solid-vapor interface excess free energies. Numerical examples of growth in two dimensions are presented for the simplest case of vanishing crystalline anisotropy and the more realistic case of a solid-liquid γ plot with cusped minima corresponding to two sets of (10 ) and (11 ) facets. The simulations reproduce many of the salient features of nanowire growth observed experimentally, including growth normal to the substrate with tapering of the side walls, transitions between different growth orientations, and crawling growth along the substrate. They also reproduce different observed relationships between the nanowire growth

  4. Crystal nucleation and dendrite growth of metastable phases in undercooled melts

    International Nuclear Information System (INIS)

    Herlach, Dieter

    2011-01-01

    Research highlights: → Homogenous nucleation. → Effects of convection on dendrite growth kinetics. → Description of disorder trapping validated by experiment. - Abstract: An undercooled melt possesses an enhanced free enthalpy that opens up the possibility to crystallize metastable crystalline solids in competition with their stable counterparts. Crystal nucleation selects the crystallographic phase whereas the growth dynamics controls microstructure evolution. We apply containerless processing techniques such as electromagnetic and electrostatic levitation to containerlesss undercool and solidify metallic melts. Owing to the complete avoidance of heterogeneous nucleation on container-walls a large undercooling range becomes accessible with the extra benefit that the freely suspended drop is direct accessible for in situ observation of crystallization far away from equilibrium. Results of investigations of maximum undercoolability on pure zirconium are presented showing the limit of maximum undercoolability set by the onset of homogeneous nucleation. Rapid dendrite growth is measured as a function of undercooling by a high-speed camera and analysed within extended theories of non-equilibrium solidification. In such both supersaturated solid solutions and disordered superlattice structure of intermetallics are formed at high growth velocities. A sharp interface theory of dendrite growth is capable to describe the non-equilibrium solidification phenomena during rapid crystallization of deeply undercooled melts. Eventually, anomalous growth behaviour of Al-rich Al-Ni alloys is presented, which may be caused by forced convection.

  5. Low-Temperature and Rapid Growth of Large Single-Crystalline Graphene with Ethane.

    Science.gov (United States)

    Sun, Xiao; Lin, Li; Sun, Luzhao; Zhang, Jincan; Rui, Dingran; Li, Jiayu; Wang, Mingzhan; Tan, Congwei; Kang, Ning; Wei, Di; Xu, H Q; Peng, Hailin; Liu, Zhongfan

    2018-01-01

    Future applications of graphene rely highly on the production of large-area high-quality graphene, especially large single-crystalline graphene, due to the reduction of defects caused by grain boundaries. However, current large single-crystalline graphene growing methodologies are suffering from low growth rate and as a result, industrial graphene production is always confronted by high energy consumption, which is primarily caused by high growth temperature and long growth time. Herein, a new growth condition achieved via ethane being the carbon feedstock to achieve low-temperature yet rapid growth of large single-crystalline graphene is reported. Ethane condition gives a growth rate about four times faster than methane, achieving about 420 µm min -1 for the growth of sub-centimeter graphene single crystals at temperature about 1000 °C. In addition, the temperature threshold to obtain graphene using ethane can be reduced to 750 °C, lower than the general growth temperature threshold (about 1000 °C) with methane on copper foil. Meanwhile ethane always keeps higher graphene growth rate than methane under the same growth temperature. This study demonstrates that ethane is indeed a potential carbon source for efficient growth of large single-crystalline graphene, thus paves the way for graphene in high-end electronical and optoelectronical applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Phase transformation in rapidly quenched Fe-Cr-Co-Mo-Ti-Si-B alloys

    Science.gov (United States)

    Zhukov, D. G.; Shubakov, V. S.; Zhukova, E. Kh; Gorshenkov, M. V.

    2018-03-01

    The research results of phase transformations in Fe-24Cr-16Co-3Mo-0.2Ti-1Si-B alloys (with a boron content of 1 to 3% by mass) obtained by rapid quenching are presented. The structure formation regularities during the melt spinning and during the subsequent crystallization annealing in rapidly quenched bands of the Fe-Cr-Co-Mo-Ti-Si-B system alloys were studied. The changes in the phase composition of the rapidly quenched Fe-Cr-Co-Mo-Ti- Si-B system alloys after quenching at various quench rates and at different boron concentrations in the alloys are studied. It is shown that during crystallization from an amorphous state, at temperatures above 570 °C, in addition to the α-phase, the σ-phase appears first, followed by the γ-phase. Heat treatment of rapidly quenched bands to high-coercive state was carried out. A qualitative assessment of magnetic properties in a high-coercivity state was carried out. An evaluation of the level of magnetic properties in a high-coercivity state allows us to conclude that the application of a magnetic field during crystallization from an amorphous state leads to anisotropy of the magnetic properties, that is, an anisotropic effect of thermo-magnetic treatment is detected.

  7. Physics of Substorm Growth Phase, Onset, and Dipolarization

    Energy Technology Data Exchange (ETDEWEB)

    C.Z. Cheng

    2003-10-22

    A new scenario of substorm growth phase, onset, and depolarization during expansion phase and the corresponding physical processes are presented. During the growth phase, as a result of enhanced plasma convection, the plasma pressure and its gradient are continued to be enhanced over the quiet-time values in the plasma sheet. Toward the late growth phase, a strong cross-tail current sheet is formed in the near-Earth plasma sheet region, where a local magnetic well is formed, the plasma beta can reach a local maximum with value larger than 50 and the cross-tail current density can be enhanced to over 10nA/m{sup 2} as obtained from 3D quasi-static magnetospheric equilibrium solutions for the growth phase. The most unstable kinetic ballooning instabilities (KBI) are expected to be located in the tailward side of the strong cross-tail current sheet region. The field lines in the most unstable KBI region map to the transition region between the region-1 and region-2 currents in the ionosphere, which is consistent with the observed initial brightening location of the breakup arc in the intense proton precipitation region. The KBI explains the AMPTE/CCE observations that a low-frequency instability with a wave period of 50-75 seconds is excited about 2-3 minutes prior to substorm onset and grows exponentially to a large amplitude at the onset of current disruption (or current reduction). At the current disruption onset higher frequency instabilities are excited so that the plasma and electromagnetic field fluctuations form a strong turbulent state. Plasma transport takes place due to the strong turbulence to relax the ambient plasma pressure profile so that the plasma pressure and current density are reduced and the ambient magnetic field intensity increases by more than a factor of 2 in the high-beta(sub)eq region and the field line geometry recovers from tail-like to dipole-like dipolarization.

  8. Growth and phase transformations of Ir on Ge(111)

    Science.gov (United States)

    Mullet, C. H.; Stenger, B. H.; Durand, A. M.; Morad, J. A.; Sato, Y.; Poppenheimer, E. C.; Chiang, S.

    2017-12-01

    The growth of Ir on Ge(111) as a function of temperature between 23 °C and 820 °C is characterized with low energy electron microscopy (LEEM), low energy electron diffraction (LEED), scanning tunneling microscopy (STM), and x-ray photoemission spectroscopy (XPS). Deposition onto a substrate at 350 °C revealed a novel growth mode consisting of multilayer Ir islands with (√3 × √3)R30° (abbreviated as √3) structure interconnected by ;bridges; of single-layer Ir several atoms wide. For deposition onto substrates above 500 °C, the √3 Ir phase grows with dendritic morphology, and substrate step bunches act as barriers to √3 Ir growth. LEEM images showed Stranski-Krastanov growth for 650-820 °C: after the √3 phase covers the surface, corresponding to 2 monolayers (ML) Ir coverage, multilayer hexagonal-shaped Ir islands form, surrounded by regions of IrGe alloy. Hexagonal-shaped Ir islands also formed upon heating 1.2 ML of √3 Ir beyond 830 °C, which resulted in the elimination of √3 structure from the surface. The transformation from √3 to (1 × 1) structure upon heating to 830 °C was an irreversible surface phase transition. Annealing > 2.0 ML of Ir in the √3 phase above the 830 °C disorder temperature, followed by cooling, produced a (3 × 1) structure. Subsequent heating and cooling through 830 °C give evidence for a reversible (3 × 1) to (1 × 1) phase transition.

  9. Physics of Substorm Growth Phase, Onset, and Dipolarization

    International Nuclear Information System (INIS)

    Cheng, C.Z.

    2003-01-01

    A new scenario of substorm growth phase, onset, and depolarization during expansion phase and the corresponding physical processes are presented. During the growth phase, as a result of enhanced plasma convection, the plasma pressure and its gradient are continued to be enhanced over the quiet-time values in the plasma sheet. Toward the late growth phase, a strong cross-tail current sheet is formed in the near-Earth plasma sheet region, where a local magnetic well is formed, the plasma beta can reach a local maximum with value larger than 50 and the cross-tail current density can be enhanced to over 10nA/m 2 as obtained from 3D quasi-static magnetospheric equilibrium solutions for the growth phase. The most unstable kinetic ballooning instabilities (KBI) are expected to be located in the tailward side of the strong cross-tail current sheet region. The field lines in the most unstable KBI region map to the transition region between the region-1 and region-2 currents in the ionosphere, which is consistent with the observed initial brightening location of the breakup arc in the intense proton precipitation region. The KBI explains the AMPTE/CCE observations that a low-frequency instability with a wave period of 50-75 seconds is excited about 2-3 minutes prior to substorm onset and grows exponentially to a large amplitude at the onset of current disruption (or current reduction). At the current disruption onset higher frequency instabilities are excited so that the plasma and electromagnetic field fluctuations form a strong turbulent state. Plasma transport takes place due to the strong turbulence to relax the ambient plasma pressure profile so that the plasma pressure and current density are reduced and the ambient magnetic field intensity increases by more than a factor of 2 in the high-beta(sub)eq region and the field line geometry recovers from tail-like to dipole-like dipolarization

  10. Differentiating the growth phases of single bacteria using Raman spectroscopy

    Science.gov (United States)

    Strola, S. A.; Marcoux, P. R.; Schultz, E.; Perenon, R.; Simon, A.-C.; Espagnon, I.; Allier, C. P.; Dinten, J.-M.

    2014-03-01

    In this paper we present a longitudinal study of bacteria metabolism performed with a novel Raman spectrometer system. Longitudinal study is possible with our Raman setup since the overall procedure to localize a single bacterium and collect a Raman spectrum lasts only 1 minute. Localization and detection of single bacteria are performed by means of lensfree imaging, whereas Raman signal (from 600 to 3200 cm-1) is collected into a prototype spectrometer that allows high light throughput (HTVS technology, Tornado Spectral System). Accomplishing time-lapse Raman spectrometry during growth of bacteria, we observed variation in the net intensities for some band groups, e.g. amides and proteins. The obtained results on two different bacteria species, i.e. Escherichia coli and Bacillus subtilis clearly indicate that growth affects the Raman chemical signature. We performed a first analysis to check spectral differences and similarities. It allows distinguishing between lag, exponential and stationary growth phases. And the assignment of interest bands to vibration modes of covalent bonds enables the monitoring of metabolic changes in bacteria caused by growth and aging. Following the spectra analysis, a SVM (support vector machine) classification of the different growth phases is presented. In sum this longitudinal study by means of a compact and low-cost Raman setup is a proof of principle for routine analysis of bacteria, in a real-time and non-destructive way. Real-time Raman studies on metabolism and viability of bacteria pave the way for future antibiotic susceptibility testing.

  11. A comparison of test statistics for the recovery of rapid growth-based enumeration tests

    NARCIS (Netherlands)

    van den Heuvel, Edwin R.; IJzerman-Boon, Pieta C.

    This paper considers five test statistics for comparing the recovery of a rapid growth-based enumeration test with respect to the compendial microbiological method using a specific nonserial dilution experiment. The finite sample distributions of these test statistics are unknown, because they are

  12. Governing Rapid Growth in Asia: State-led Development in Historical Perspective

    NARCIS (Netherlands)

    T-W. Ngo (Tak-Wing)

    2009-01-01

    textabstractRapid growth in Asia has often been explained in terms of effective policies pursued by a “developmental state”. In particular, countries in East Asia are said to be characterized by the presence of a strong state with technocratic capacity and social embeddedness. This inaugural address

  13. Phase Characterization of Cucumber Growth: A Chemical Gel Model

    Directory of Open Access Journals (Sweden)

    Bo Li

    2016-01-01

    Full Text Available Cucumber grows with complex phenomena by changing its volume and shape, which is not fully investigated and challenges agriculture and food safety industry. In order to understand the mechanism and to characterize the growth process, the cucumber is modeled as a hydrogel in swelling and its development is studied in both preharvest and postharvest stages. Based on thermodynamics, constitutive equations, incorporating biological quantities, are established. The growth behavior of cucumber follows the classic theory of continuous or discontinuous phase transition. The mechanism of bulged tail in cucumber is interpreted by phase coexistence and characterized by critical conditions. Conclusions are given for advances in food engineering and novel fabrication techniques in mechanical biology.

  14. The performance studies of DKDP crystals grown by a rapid horizontal growth method

    Science.gov (United States)

    Xie, Xiaoyi; Qi, Hongji; Wang, Bin; Wang, Hu; Chen, Duanyang; Shao, Jianda

    2018-04-01

    A deuterated potassium dihydrogen phosphate (DKDP) crystal with about 70% deuterium level was grown by a rapid horizontal growth method with independent design equipment, which includes a continuous filtration system. The cooling program during crystal growth was designed according to a self-developed software to catch the size of growing crystal in real time. The crystal structure, optical performance and laser induced damage threshold (LIDT) of this DKDP crystal were investigated in this paper. The deuterium concentration of the crystal was confirmed by the neutron diffraction technique, which was effective and available in determining a complete range of deuteration level. The dielectric property was measured to evaluate the perfection of the lattice. The transmittance and LIDT were carried out further to evaluate the optical and functional properties of this DKDP crystal grown in the rapid horizontal growth technique. All of the detailed characterization for DKDP figured out that the 70% deuterated KDP crystal grown in this way had relatively good qualities.

  15. Global properties of the magnetosphere during a substorm growth phase: A case study

    International Nuclear Information System (INIS)

    Baker, D.N.; Hones, E.W. Jr.; Higbie, P.R.; Belian, R.D.; Stauning, P.

    1981-01-01

    At approximately 0100 UT on December 29, 1976, a large injection of energetic (>30 keV) particles was observed by Los Alamos instrumentation onboard spacecraft 1976--059 (35 0 W longitude) at geostationary orbit. This injection was closely associated with the onset of a major substorm (also at 0100 UT) identified by sharp negative bays in the H components of magnetic records at Leirvogur (22 0 W) and Narssarssuaq (45 0 W) and by the occurrence of a positive H component bay at 0100 UT in the mid-latitude magnetogram record at M'Bour (17 0 W). This substorm expansion onset (and concomitant particle injection) was preceded (between 2330 and 0100 UT) by a pronounced 'stretching' of the magnetic field at synchronous orbit into a taillike configuration and by a development of highly cigarlike (field-aligned) electron distributions at geostationary orbit that we have in the past identified with the substorm growth phase. Of principal importance in this case are two other auxiliary data sets. The first is a well-timed set of DMSP auroral images taken during the course of the growth and expansion phases of the substorm. The images before and during the growth (cigar) phase, including one auroral zone crossing at approx.0050 UT, show quiet aurora with no observable substorm activity in the visible polar region. The second relevant data set is a broad set of riometer data from 13 separate stations in three general meridians (west coast Greenland, east coast Greenland, and northern Scandinavia) from magnetic latitudes of approx.65 0 to approx.90 0 . The riometer data also show clearly that there was no measurable substorm activity anywhere, either in longitude or latitude, as the magnetosphere developed its very stressed, growth-phase configuration prior to substorm expansion onset. These results support the concept of a storage of energy (growth phase) prior to its rapid release at substorm onset

  16. Diffusion and phase growth in heterophase systems. 1

    International Nuclear Information System (INIS)

    Mchedlov-Petrosyan, P.O.

    1989-01-01

    The present paper gives the view of theoretical study of diffusion processes in ternary and more component solid-state systems, caused by chemical reactions and phase growth. Internal oxidation of alloys, nitridation, borating etc. are the well-known and widely investigated processes of such type. Self-consistent theoretical model of such processes must take into account both the effect of concentration macroscopic districutions on new phase precipitation growth and precipitation reaction on concentration distribution; heterophase must be explicitly allowed for. As for binary system, diffusion theory, running into the phase growth, is well developed and completely presented in monographs, the carried out theoretical investigations of ternary systems are explicitly deficient. The first part of the review presents analysis of available theoretical studies approximately up to 1980. Ratios between various analytically solved models are discussed in detail. It is shown that they don't satisfy to full extent the above-given requirements. More consistent, both numerically and analytically solvable models developed for the last years, are considered in the review second part. 119 refs

  17. Previsibilidade de sucesso na disjunção palatina avaliada pelo estágio de maturação esquelética: estudo piloto Sucess predictability in rapid maxillary expansion when assessed by skeletal growth maturation phase: pilot study

    Directory of Open Access Journals (Sweden)

    Rodrigo Rezende de Albuquerque

    2006-04-01

    Full Text Available OBJETIVO: a proposta deste estudo foi determinar se a previsibilidade de sucesso da disjunção palatina está correlacionada a algum evento de maturidade esquelética que determine o final do crescimento geral do organismo. METODOLOGIA: utilizando o conhecimento dos estágios de maturação esquelética visualizados por radiografia de mão e punho e registrados em um gráfico do surto de crescimento puberal, foram avaliados dezenove pacientes de ambos os gêneros, com idades variando de dez anos e três meses a vinte e oito anos e quatro meses, supervisionados por análises clínicas e radiográficas específicas antes e após o procedimento de disjunção palatina. RESULTADO E CONCLUSÃO: pode-se afirmar que não foi possível determinar a previsibilidade de sucesso da disjunção palatina quando esta foi correlacionada com a ossificação total do osso rádio.AIM: to evaluate the possibility of rapid maxillary expansion in patients who have reached the decisive event of facial growth ending (total fusion of the radius. METHODS: the study was held using esqueletal maturation data from hand and wrist x-ray plotted in a puberal growth spurt graph from nineteen patients of both genders at ages ranging from ten years and three months to twenty-eight years and four months surveilled by specific clinical and radiographic analysis before and after the rapid maxillary expansion procedure. RESULTS AND CONCLUSION: it could be concluded that it was not possible to establish a successful correlation between total fusion of radius with rapid maxillary expansion.

  18. Growth Law For Peritectic Phases Formation In The Zinc Coating

    Directory of Open Access Journals (Sweden)

    Guzik E.

    2015-09-01

    Full Text Available Some experiments dealing with the isothermal hot dip galvanizing were carried out. The (Zn – coating settled on the Armco-iron substrate were examined after arresting the solidification for different periods of time. The measurement of the thickness of each sub-layer in the coating were performed due to the SEM – analysis. The zinc segregation on the cross-section of the studied sub-layers were also determined by the EDS technique. The growth laws are formulated mathematically for each of the observed sub-layer. The mechanism of the sub-layer formation is also analysed due to the observation of the birth/nucleation of the phases in the sub-layers and the effect of flux onto the sub-layers morphology formation. The appearance of each phase is referred to the Fe-Zn diagram for stable equilibrium according to which these phases are the products of the adequate peritectic transformation.

  19. The Great Transformations of Tibet and Xinjiang: a comparative analysis of rapid labour transitions in times of rapid growth in two contested minority regions of China

    NARCIS (Netherlands)

    A.M. Fischer (Andrew Martín)

    2011-01-01

    textabstractRapid growth since the mid-1990s in the Tibetan and Uyghur areas in Western China has been associated with the rapid transition of the local (mostly Tibetan and Uyghur) labour forces out of the primary sector (mostly farming and herding) and into the tertiary sector (services). The TAR,

  20. Rapid growth of the US wildland-urban interface raises wildfire risk.

    Science.gov (United States)

    Radeloff, Volker C; Helmers, David P; Kramer, H Anu; Mockrin, Miranda H; Alexandre, Patricia M; Bar-Massada, Avi; Butsic, Van; Hawbaker, Todd J; Martinuzzi, Sebastián; Syphard, Alexandra D; Stewart, Susan I

    2018-03-27

    The wildland-urban interface (WUI) is the area where houses and wildland vegetation meet or intermingle, and where wildfire problems are most pronounced. Here we report that the WUI in the United States grew rapidly from 1990 to 2010 in terms of both number of new houses (from 30.8 to 43.4 million; 41% growth) and land area (from 581,000 to 770,000 km 2 ; 33% growth), making it the fastest-growing land use type in the conterminous United States. The vast majority of new WUI areas were the result of new housing (97%), not related to an increase in wildland vegetation. Within the perimeter of recent wildfires (1990-2015), there were 286,000 houses in 2010, compared with 177,000 in 1990. Furthermore, WUI growth often results in more wildfire ignitions, putting more lives and houses at risk. Wildfire problems will not abate if recent housing growth trends continue.

  1. Rapid Growth of Uropathogenic Escherichia coli during Human Urinary Tract Infection

    Directory of Open Access Journals (Sweden)

    Valerie S. Forsyth

    2018-03-01

    Full Text Available Uropathogenic Escherichia coli (UPEC strains cause most uncomplicated urinary tract infections (UTIs. These strains are a subgroup of extraintestinal pathogenic E. coli (ExPEC strains that infect extraintestinal sites, including urinary tract, meninges, bloodstream, lungs, and surgical sites. Here, we hypothesize that UPEC isolates adapt to and grow more rapidly within the urinary tract than other E. coli isolates and survive in that niche. To date, there has not been a reliable method available to measure their growth rate in vivo. Here we used two methods: segregation of nonreplicating plasmid pGTR902, and peak-to-trough ratio (PTR, a sequencing-based method that enumerates bacterial chromosomal replication forks present during cell division. In the murine model of UTI, UPEC strain growth was robust in vivo, matching or exceeding in vitro growth rates and only slowing after reaching high CFU counts at 24 and 30 h postinoculation (hpi. In contrast, asymptomatic bacteriuria (ABU strains tended to maintain high growth rates in vivo at 6, 24, and 30 hpi, and population densities did not increase, suggesting that host responses or elimination limited population growth. Fecal strains displayed moderate growth rates at 6 hpi but did not survive to later times. By PTR, E. coli in urine of human patients with UTIs displayed extraordinarily rapid growth during active infection, with a mean doubling time of 22.4 min. Thus, in addition to traditional virulence determinants, including adhesins, toxins, iron acquisition, and motility, very high growth rates in vivo and resistance to the innate immune response appear to be critical phenotypes of UPEC strains.

  2. Formation of metastable phases and nanocomposite structures in rapidly solidified Al-Fe alloys

    International Nuclear Information System (INIS)

    Nayak, S.S.; Chang, H.J.; Kim, D.H.; Pabi, S.K.; Murty, B.S.

    2011-01-01

    Highlights: → Structures of nanocomposites in rapidly solidified Al-Fe alloys were investigated. → Nanoquasicrystalline, amorphous and intermetallics phases coexist with α-Al. → Nanoquasicrystalline phase was observed for the first time in the dilute Al alloys. → Thermodynamic driving force plays dominant role in precipitation of Fe-rich phases. → High hardness (3.57 GPa) was observed for nanocomposite of Al-10Fe alloy. - Abstract: In the present work the structure and morphology of the phases of nanocomposites formed in rapidly solidified Al-Fe alloys were investigated in details using analytical transmission electron microscopy and X-ray diffraction. Nanoquasicrystalline phases, amorphous phase and intermetallics like Al 5 Fe 2 , Al 13 F 4 coexisted with α-Al in nanocomposites of the melt spun alloys. It was seen that the Fe supersaturation in α-Al diminished with the increase in Fe content and wheel speed indicating the dominant role of the thermodynamic driving force in the precipitation of Fe-rich phases. Nanoquasicrystalline phases were observed for the first time in the dilute Al alloys like Al-2.5Fe and Al-5Fe as confirmed by high resolution TEM. High hardness (3.57 GPa) was measured in nanocomposite of Al-10Fe alloy, which was attributed to synergistic effect of solid solution strengthening due to high solute content (9.17 at.% Fe), dispersion strengthening by high volume fraction of nanoquasicrystalline phase; and Hall-Petch strengthening from finer cell size (20-30 nm) of α-Al matrix.

  3. Examination of rapid phase change in copper wires to improve material models and understanding of burst

    Science.gov (United States)

    Olles, Joseph; Garasi, Christopher; Ball, J. Patrick

    2017-11-01

    Electrically-pulsed wires undergo multiple phase changes including a postulated metastable phase resulting in explosive wire growth. Simulations using the MHD approximation attempt to account for the governing physics, but lack the material properties (equations-of-state and electrical conductivity) to accurately predict the phase evolution of the exploding (bursting) wire. To explore the dynamics of an exploding copper wire (in water), we employ a digital micro-Schlieren streak photography technique. This imaging quantifies wire expansion and shock waves emitted from the wire during phase changes. Using differential voltage probes, a Rogowski coil, and timing fiducials, the phase change of the wire is aligned with electrical power and energy deposition. Time-correlated electrical diagnostics and imaging allow for detailed validation of MHD simulations, comparing observed phases with phase change details found in the material property descriptions. In addition to streak imaging, a long exposure image is taken to capture axial striations along the length of the wire. These images are used to compare with results from 3D MHD simulations which propose that these perturbations impact the rate of wire expansion and temporal change in phases. If successful, the experimental data will identify areas for improvement in the material property models, and modeling results will provide insight into the details of phase change in the wire with correlation to variations in the electrical signals.

  4. Phase composition of rapidly solidified Ag-Sn-Cu dental alloys

    International Nuclear Information System (INIS)

    Lecong Dzuong; Do Minh Nghiep; Nguyen van Dzan; Cao the Ha

    1996-01-01

    The phase composition of some rapidly solidified Ag-Sn-Cu dental alloys with different copper contents (6.22 wtpct) has been studied by XRD, EMPA and optical microscopy. The samples were prepared from melt-spun ribbons. The microstructure of the as-quenched ribbons was microcrystalline and consisted of the Ag sub 3 Sn, Ag sub 4 Sn, Cu sub 3 Sn and Cu sub 3 Sn sub 8 phases. Mixing with mercury (amalgamation) led to formation of the Ag sub 2 Hg sub 3, Sn sub 7 Hg and Cu sub 6 Sn sub 5 phases. The amount of copper atoms in the alloys played an important role in phase formation in the amalgams

  5. Phase mapping of iron-based rapidly quenched alloys using precession electron diffraction

    International Nuclear Information System (INIS)

    Svec, P.; Janotova, I.; Hosko, J.; Matko, I.; Janickovic, D.; Svec, P. Sr.; Kepaptsoglou, D. M.

    2013-01-01

    The present contribution is focused on application of PED and phase/orientation mapping of nanocrystals of bcc-Fe formed during the first crystallization stage of amorphous Fe-Co-Si-B ribbon. Using precession electron diffraction and phase/orientation mapping the formation of primary crystalline phase, bcc-Fe, from amorphous Fe-Co-Si-B has been analyzed. Important information about mutual orientation of the phase in individual submicron grains as well as against the sample surface has been obtained. This information contributes to the understanding of micromechanisms controlling crystallization from amorphous rapidly quenched structure and of the structure of the original amorphous state. The presented technique due to its high spatial resolution, speed and information content provided complements well classical techniques, especially in nanocrystalline materials. (authors)

  6. Rapid growth, early maturation and short generation time in African annual fishes

    Czech Academy of Sciences Publication Activity Database

    Blažek, Radim; Polačik, Matej; Reichard, Martin

    2013-01-01

    Roč. 4, č. 24 (2013), s. 24 ISSN 2041-9139 R&D Projects: GA ČR(CZ) GAP506/11/0112 Institutional support: RVO:68081766 Keywords : extreme life history * annual fish * explosive growth * rapid maturation * generation time * killifish * diapause * vertebrate * reaction norm * Savanna Subject RIV: EG - Zoology Impact factor: 3.104, year: 2013 http://www.evodevojournal.com/content/4/1/24

  7. Rapid growth of the US wildland-urban interface raises wildfire risk

    Science.gov (United States)

    Volker C. Radeloff; David P. Helmers; H. Anu Kramer; Miranda H. Mockrin; Patricia M. Alexandre; Avi Bar-Massada; Van Butsic; Todd J. Hawbaker; Sebastián Martinuzzi; Alexandra D. Syphard; Susan I. Stewart

    2018-01-01

    The wildland-urban interface (WUI) is the area where houses and wildland vegetation meet or intermingle, and where wildfire problems are most pronounced. Here we report that the WUI in the United States grew rapidly from 1990 to 2010 in terms of both number of new houses (from 30.8 to 43.4 million; 41% growth) and land area (from 581,000 to 770,000 km2...

  8. Rapid growth and childhood obesity are strongly associated with lysoPC(14:0).

    Science.gov (United States)

    Rzehak, Peter; Hellmuth, Christian; Uhl, Olaf; Kirchberg, Franca F; Peissner, Wolfgang; Harder, Ulrike; Grote, Veit; Weber, Martina; Xhonneux, Annick; Langhendries, Jean-Paul; Ferre, Natalia; Closa-Monasterolo, Ricardo; Verduci, Elvira; Riva, Enrica; Socha, Piotr; Gruszfeld, Dariusz; Koletzko, Berthold

    2014-01-01

    Despite the growing interest in the early-origins-of-later-disease hypothesis, little is known about the metabolic underpinnings linking infant weight gain and childhood obesity. To discover biomarkers reflective of weight change in the first 6 months and overweight/obesity at age 6 years via a targeted metabolomics approach. This analysis comprised 726 infants from a European multicenter randomized trial (Childhood Obesity Programme, CHOP) for whom plasma blood samples at age 6 months and anthropometric data up to the age of 6 years were available. 'Rapid growth' was defined as a positive difference in weight within the first 6 months of life standardized to WHO growth standards. Weight change was regressed on each of 168 metabolites (acylcarnitines, lysophosphatidylcholines, sphingomyelins, and amino acids). Metabolites significant after Bonferroni's correction were tested as predictors of later overweight/obesity. Among the overall 19 significant metabolites, 4 were associated with rapid growth and 15 were associated with a less-than-ideal weight change. After adjusting for feeding group, only the lysophosphatidylcholine LPCaC14:0 remained significantly associated with rapid weight gain (β = 0.18). Only LPCaC14:0 at age 6 months was predictive of overweight/obesity at age 6 years (OR 1.33; 95% CI 1.04-1.69). LPCa14:0 is strongly related to rapid growth in infancy and childhood overweight/obesity. This suggests that LPCaC14:0 levels may represent a metabolically programmed effect of infant weight gain on the later obesity risk. However, these results require confirmation by independent cohorts. © 2014 S. Karger AG, Basel.

  9. An Inquiry into the Rapid Growth of the Garment Industry in Bangladesh

    OpenAIRE

    MOTTALEB, Khondoker Abdul; SONOBE, Tetsushi

    2011-01-01

    The export-oriented garment industry in Bangladesh has grown rapidly for the last three decades and now ranks among the largest garment exporters in the world. While its early success is attributed to the initial technology transfer from South Korea, such a one-time infusion of knowledge alone is insufficient to explain the sustained growth for three decades. This paper uses primary data collected from knitwear manufacturers and garment traders to explore the process of the continuous learnin...

  10. Colorimetry provides a rapid objective measurement of de novo hair growth rate in mice.

    Science.gov (United States)

    Tzung, Tien-Yi; Yang, Chia-Yi; Huang, Yung-Chang; Kao, Fu-Jen

    2009-11-01

    Depilated mice have been used as a test platform for hair growth-regulating agents. However, currently available assessment tools for hair growth in mice are less than ideal. Tristimulus colorimetry of the fur color of depilated agouti, albino, and black mice with L*, a*, and b* values were performed daily until the full growth of pelage. Using light-emitting diode (LED) irradiation (650 and 890 nm) with a daily dose of 3.5 J/cm(2) as hair growth regulators, the hair growth rates observed by the global assessment were compared with those derived from colorimetry. In contrast to a* and b* values, L* values changed more drastically over time in the anagen phase regardless of fur color. Unlike the inhibitory effect of 650 nm irradiation, LED of 890 nm promoted de novo hair regrowth in mice. The difference in hair growth rates detected by colorimetry paralleled the observation made by the global assessment. The L* value of fur color obtained by tristimulus colorimetry was a sensitive yet quantitative indicator of de novo hair growth, and could be used to project the hair growth rate in mice.

  11. Characterization of secondary phases in modified vertical bridgman growth czt

    Energy Technology Data Exchange (ETDEWEB)

    Duff, Martine

    2009-07-10

    CdZnTe or 'CZT' crystals are highly suitable for use as a room temperature based spectrometer for the detection and characterization of gamma radiation. Over the last decade, the methods for growing high quality CZT have improved the quality of the produced crystals however there are material features that can influence the performance of these materials as radiation detectors. For example, various structural heterogeneities within the CZT crystals, such as twinning, pipes, grain boundaries (polycrystallinity), and secondary phases (SP) can have a negative impact on the detector performance. In this study, a CZT material was grown by the modified vertical Bridgman growth (MVB) method with zone leveled growth without excess Te in the melt. Visual observations of material from the growth of this material revealed significant voids and SP. Three samples from this material was analyzed using various analytical techniques to evaluate its electrical properties, purity and detector performance as radiation spectrometers and to determine the morphology, dimension and elemental/structural composition of one of the SP in this material. This material was found to have a high resistivity but poor radiation spectrometer performance. It had SP that were rich in polycrystalline aluminum oxide (Al{sub 2}O{sub 3}), metallic Te and polycrystalline CdZnTe and 15 to 50 {micro}m in diameter. Bulk elemental analyses of sister material from elsewhere in the boule did not contain high levels of Al so there is considerable elemental impurity heterogeneity within the boule from this growth.

  12. Characterization of secondary phases in modified vertical bridgman growth czt

    International Nuclear Information System (INIS)

    Duff, Martine

    2009-01-01

    CdZnTe or 'CZT' crystals are highly suitable for use as a room temperature based spectrometer for the detection and characterization of gamma radiation. Over the last decade, the methods for growing high quality CZT have improved the quality of the produced crystals however there are material features that can influence the performance of these materials as radiation detectors. For example, various structural heterogeneities within the CZT crystals, such as twinning, pipes, grain boundaries (polycrystallinity), and secondary phases (SP) can have a negative impact on the detector performance. In this study, a CZT material was grown by the modified vertical Bridgman growth (MVB) method with zone leveled growth without excess Te in the melt. Visual observations of material from the growth of this material revealed significant voids and SP. Three samples from this material was analyzed using various analytical techniques to evaluate its electrical properties, purity and detector performance as radiation spectrometers and to determine the morphology, dimension and elemental/structural composition of one of the SP in this material. This material was found to have a high resistivity but poor radiation spectrometer performance. It had SP that were rich in polycrystalline aluminum oxide (Al 2 O 3 ), metallic Te and polycrystalline CdZnTe and 15 to 50 (micro)m in diameter. Bulk elemental analyses of sister material from elsewhere in the boule did not contain high levels of Al so there is considerable elemental impurity heterogeneity within the boule from this growth

  13. Rapid solidification growth mode transitions in Al-Si alloys by dynamic transmission electron microscopy

    International Nuclear Information System (INIS)

    Roehling, John D.; Coughlin, Daniel R.; Gibbs, John W.; Baldwin, J. Kevin; Mertens, James C.E.; Campbell, Geoffrey H.; Clarke, Amy J.; McKeown, Joseph T.

    2017-01-01

    In situ dynamic transmission electron microscope (DTEM) imaging of Al-Si thin-film alloys was performed to investigate rapid solidification behavior. Solidification of alloys with compositions from 1 to 15 atomic percent Si was imaged during pulsed laser melting and subsequent solidification. Solely α-Al solidification was observed in Al-1Si and Al-3Si alloys, and solely kinetically modified eutectic growth was observed in Al-6Si and Al-9Si alloys. A transition in the solidification mode in eutectic and hypereutectic alloys (Al-12Si and Al-15Si) from nucleated α-Al dendrites at lower solidification velocities to planar eutectic growth at higher solidification velocities was observed, departing from trends previously seen in laser-track melting experiments. Comparisons of the growth modes and corresponding velocities are compared with previous solidification models, and implications regarding the models are discussed.

  14. Electromagnetic induction heating for single crystal graphene growth: morphology control by rapid heating and quenching

    Science.gov (United States)

    Wu, Chaoxing; Li, Fushan; Chen, Wei; Veeramalai, Chandrasekar Perumal; Ooi, Poh Choon; Guo, Tailiang

    2015-03-01

    The direct observation of single crystal graphene growth and its shape evolution is of fundamental importance to the understanding of graphene growth physicochemical mechanisms and the achievement of wafer-scale single crystalline graphene. Here we demonstrate the controlled formation of single crystal graphene with varying shapes, and directly observe the shape evolution of single crystal graphene by developing a localized-heating and rapid-quenching chemical vapor deposition (CVD) system based on electromagnetic induction heating. Importantly, rational control of circular, hexagonal, and dendritic single crystalline graphene domains can be readily obtained for the first time by changing the growth condition. Systematic studies suggest that the graphene nucleation only occurs during the initial stage, while the domain density is independent of the growth temperatures due to the surface-limiting effect. In addition, the direct observation of graphene domain shape evolution is employed for the identification of competing growth mechanisms including diffusion-limited, attachment-limited, and detachment-limited processes. Our study not only provides a novel method for morphology-controlled graphene synthesis, but also offers fundamental insights into the kinetics of single crystal graphene growth.

  15. Phase composition and microhardness of rapidly quenched Al-Fe alloys after high pressure torsion deformation

    Energy Technology Data Exchange (ETDEWEB)

    Tcherdyntsev, V.V.; Kaloshkin, S.D.; Gunderov, D.V.; Afonina, E.A.; Brodova, I.G.; Stolyarov, V.V.; Baldokhin, Yu.V.; Shelekhov, E.V.; Tomilin, I.A

    2004-07-15

    Aluminium-based Al-Fe alloys with Fe content of 2, 8, and 10 wt.% were prepared by rapid quenching (RQ) from the melt at a rate of 10{sup 6} K/s. Structure of the alloys was examined by X-ray diffraction (XRD) and Moessbauer spectroscopy. Phase transformations of RQ alloys by high pressure torsion (HPT) were studied. Dependences of phase composition on the intensity of HPT were investigated. Microhardness measurements of HPT alloys show a considerable structural heterogeneity of specimens, the dependence of microhardness on the radius of the pills was found out. Phase composition and microhardness during the heating were investigated. At the initial step of heating (120-150 deg. C), an increase in microhardness was observed, whereas further heating leads to a decrease in the microhardness.

  16. The nucleation and growth of intermetallic Al-Pt phases

    International Nuclear Information System (INIS)

    Kovacs, A.; Barna, P.B.; Labar, J. l.

    2002-01-01

    The nucleation and growth of intermetallic Al-Pt phases on amorphous carbon was investigated by half shadow technique in co-deposited thin films. In such experimental condition, the composition of the deposited films varied in the range of Al x Pt 1-x (0≤x≤0.6). The coexistence of Al 5 Pt, Al 2 Pt, Al 3 Pt 2 intermetallic phases have been found in the whole range with varying ratio. Vapour depositions were performed in an UHV system. The Al and Pt components were evaporated simultaneously onto amorphous carbon layer supported by TEM micro-grids. Deposition rates were controlled separately by quartz crystal monitors. Substrate temperature during deposition was 350 grad C. A special evaporation arrangement made possible to create a half shadow area on the substrate in which the quantity one of the components increased from zero to the wanted composition of the sample. The composition of the zones was determined by energy dispersive X-ray spectroscopy (EDS) in TEM. The intermetallic phases developed in the sample were investigated by analytical TEM (Philips CM20) and high resolution TEM (JEOL 3010 UHR). The electron diffraction patterns have been evaluated by ProcessDiffraction program. (Authors)

  17. Rapid and Controlled In Situ Growth of Noble Metal Nanostructures within Halloysite Clay Nanotubes.

    Science.gov (United States)

    Rostamzadeh, Taha; Islam Khan, Md Shahidul; Riche', Kyle; Lvov, Yuri M; Stavitskaya, Anna V; Wiley, John B

    2017-11-14

    A rapid (≤2 min) and high-yield low-temperature synthesis has been developed for the in situ growth of gold nanoparticles (NPs) with controlled sizes in the interior of halloysite nanotubes (HNTs). A combination of HAuCl 4 in ethanol/toluene, oleic acid, and oleylamine surfactants and ascorbic acid reducing agent with mild heating (55 °C) readily lead to the growth of targeted nanostructures. The sizes of Au NPs are tuned mainly by adjusting nucleation and growth rates. Further modification of the process, through an increase in ascorbic acid, allows for the formation of nanorods (NRs)/nanowires within the HNTs. This approach is not limited to gold-a modified version of this synthetic strategy can also be applied to the formation of Ag NPs and NRs within the clay nanotubes. The ability to readily grow such core-shell nanosystems is important to their further development as nanoreactors and active catalysts. NPs within the tube interior can further be manipulated by the electron beam. Growth of Au and Ag could be achieved under a converged electron beam suggesting that both Au@HNT and Ag@HNT systems can be used for the fundamental studies of NP growth/attachment.

  18. Is rapid growth in Internet usage environmentally sustainable for Australia? An empirical investigation.

    Science.gov (United States)

    Salahuddin, Mohammad; Alam, Khorshed; Ozturk, Ilhan

    2016-03-01

    This study estimates the short- and long-run effects of Internet usage and economic growth on carbon dioxide (CO2) emissions using annual time series macro data for Australia for the period 1985-2012. Autoregressive distributive lag (ARDL) bounds and Gregory-Hansen structural break cointegration tests are applied. ARDL estimates indicate no significant long-run relationship between Internet usage and CO2 emissions, which implies that the rapid growth in Internet usage is still not an environmental threat for Australia. The study further indicates that higher level of economic growth is associated with lower level of CO2 emissions; however, Internet usage and economic growth have no significant short-run relationship with CO2 emissions. Financial development has both short-run and long-run significant positive association with CO2 emissions. The findings offer support in favor of energy efficiency gains and a reduction in energy intensity in Australia. However, impulse response and variance decomposition analysis suggest that Internet usage, economic growth and financial development will continue to impact CO2 emissions in the future, and as such, this study recommends that in addition to the existing measures to combat CO2 emissions, Australia needs to exploit the potential of the Internet not only to reduce its own carbon footprint but also to utilize information and communication technology (ICT)-enabled emissions abatement potential to reduce emissions in various other sectors across the economy, such as, power, renewable energy especially in solar and wind energy, agriculture, transport and service.

  19. Large plasma-membrane depolarization precedes rapid blue-light-induced growth inhibition in cucumber

    Science.gov (United States)

    Spalding, E. P.; Cosgrove, D. J.

    1989-01-01

    Blue-light (BL)-induced suppression of elongation of etiolated Cucumis sativus L. hypocotyls began after a 30-s lag time, which was halved by increasing the fluence rate from 10 to 100 micromoles m-2 s-1. Prior to the growth suppression, the plasma-membrane of the irradiated cells depolarized by as much as 100 mV, then returned within 2-3 min to near its initial value. The potential difference measured with surface electrodes changed with an identical time course but opposite polarity. The lag time for the change in surface potential showed an inverse dependence on fluence rate, similar to the lag for the growth inhibition. Green light and red light caused neither the electrical response nor the rapid inhibition of growth. The depolarization by BL did not propagate to nonirradiated regions and exhibited a refractory period of about 10 min following a BL pulse. Fluence-response relationships for the electrical and growth responses provide correlational evidence that the plasma-membrane depolarization reflects an event in the transduction chain of this light-growth response.

  20. Prenatal exposure to traffic pollution: associations with reduced fetal growth and rapid infant weight gain.

    Science.gov (United States)

    Fleisch, Abby F; Rifas-Shiman, Sheryl L; Koutrakis, Petros; Schwartz, Joel D; Kloog, Itai; Melly, Steven; Coull, Brent A; Zanobetti, Antonella; Gillman, Matthew W; Gold, Diane R; Oken, Emily

    2015-01-01

    Prenatal air pollution exposure inhibits fetal growth, but implications for postnatal growth are unknown. We assessed weights and lengths of US infants in the Project Viva cohort at birth and 6 months. We estimated 3rd-trimester residential air pollution exposures using spatiotemporal models. We estimated neighborhood traffic density and roadway proximity at birth address using geographic information systems. We performed linear and logistic regression adjusted for sociodemographic variables, fetal growth, and gestational age at birth. Mean birth weight-for-gestational age z-score (fetal growth) was 0.17 (standard deviation [SD] = 0.97; n = 2,114), 0- to 6-month weight-for-length gain was 0.23 z-units (SD = 1.11; n = 689), and 17% had weight-for-length ≥95th percentile at 6 months of age. Infants exposed to the highest (vs. lowest) quartile of neighborhood traffic density had lower fetal growth (-0.13 units [95% confidence interval (CI) = -0.25 to -0.01]), more rapid 0- to 6-month weight-for-length gain (0.25 units [95% CI = 0.01 to 0.49]), and higher odds of weight-for-length ≥95th percentile at 6 months (1.84 [95% CI = 1.11 to 3.05]). Neighborhood traffic density was additionally associated with an infant being in both the lowest quartile of fetal growth and the highest quartile of 0- to 6-month weight-for-length gain (Q4 vs. Q1, odds ratio = 3.01 [95% CI = 1.08 to 8.44]). Roadway proximity and 3rd-trimester black carbon exposure were similarly associated with growth outcomes. For 3rd-trimester particulate matter (PM2.5), effect estimates were in the same direction, but smaller and imprecise. Infants exposed to higher traffic-related pollution in early life may exhibit more rapid postnatal weight gain in addition to reduced fetal growth.

  1. Texture control and growth mechanism of WSe{sub 2} film prepared by rapid selenization of W film

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hongchao [State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083 (China); Chongyi Zhangyuan Tungsten Industry Corporation Limited, Ganzhou 341300 (China); Gao, Di; Li, Kun; Pang, Mengde; Xie, Senlin [State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083 (China); Liu, Rutie, E-mail: llrrtt@csu.edu.cn [State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083 (China); Zou, Jianpeng [State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083 (China)

    2017-02-01

    Highlights: • We present a highly efficient method for preparing WSe{sub 2} film by rapid selenization. • The W film phase composition has little effect on WSe{sub 2} film orientation. • W film density is a critical factor that influences the WSe{sub 2} orientation. • A growth model was proposed for two kinds of WSe{sub 2} film textures. - Abstract: The tungsten diselenide (WSe{sub 2}) films with different orientation present unique properties suitable for specific applications, such as WSe{sub 2} with a C-axis⊥substrate for optoelectronics and WSe{sub 2} with a C-axis // substrate for electrocatalysts. Orientation control of WSe{sub 2} is essential for realizing the practical applications. In this letter, a WSe{sub 2} film has been prepared via rapid selenization of a magnetron-sputtered tungsten (W) film. The influence of the magnetron-sputtered W film on WSe{sub 2} film growth was studied systematically. Scanning electron microscopy, X-ray diffractometry and high-resolution transmission electron microscopy were used to evaluate the morphology, microstructure and phase composition of the W and WSe{sub 2} films. The substrate temperature has a significant effect on the W film phase composition, but little effect on the WSe{sub 2} film orientation. The WSe{sub 2} orientation can be controlled by changing the W film microstructure. A dense W film that is deposited at low pressure is conducive to the formation of WSe{sub 2} with a C-axis⊥substrate, whereas a porous W film deposited at high pressure favors the formation of WSe{sub 2} with a C-axis // substrate. A growth model for the WSe{sub 2} film with different texture has been proposed based on the experimental results. The direction of selenium (Se) vapor diffusion differs at the top and side surfaces. This is a key factor for the preparation of anisotropic WSe{sub 2} films. Highly oriented WSe{sub 2} films with a C-axis⊥substrate grow from the dense W film deposited at low pressure because Se vapor

  2. Driving forces of rapid CO2 emissions growth: A case of Korea

    International Nuclear Information System (INIS)

    Kim, Yong-Gun; Yoo, Jonghyun; Oh, Wankeun

    2015-01-01

    This study aims to investigate Korea's final demand structure and its impacts on CO 2 emissions in order to reduce CO 2 emissions and develop environmental policy directions. Based on the environmentally extended input–output model, this study adopts a two-step approach: (1) to estimate the embodied emissions and their intensities for 393 sectors induced by final demand; and (2) to calculate the driving factors of emission growth between 2003 and 2011 and then evaluate the result by using Structural Decomposition Analysis (SDA). The findings of this study demonstrate that the impact of composition change in export with less embodied emission intensities tends to offset the increase in CO 2 emission by the export scale growth. The relatively low residential electricity price has resulted in the rapid growth of household electricity consumption and significantly contributed to emissions growth. The result of SDA indicates that Korea's final demand behavior yielded high carbonization over the same period. The findings suggest that Korean government should promote exports in industries with less embedded CO 2 in order to protect environments. In addition, emission information of each product and service should be provided for consumers to change their purchase patterns towards contributing to low carbon emissions as active players. -- Highlights: •We investigate Korea's final demand structure and its contribution to CO 2 emissions. •Using SDA, we evaluate the driving factors of emission growth from 2003 to 2011. •Exports play a critical role in Korea's CO 2 emissions growth. •The relatively low residential electricity price has contributed to emission growth. •Korea's final demand behavior yielded high carbonization over the same period

  3. A three-phase microfluidic chip for rapid sample clean-up of alkaloids from plant extracts

    NARCIS (Netherlands)

    Tetala, K.K.R.; Swarts, J.W.; Chen, B.; Janssen, A.E.M.; Beek, van T.A.

    2009-01-01

    A three-phase microchip was developed for the rapid and efficient small-scale purification of alkaloids from plant extracts. As part of the development of such a three-phase microchip, first a two-phase microchip with two channels (3.2 cm and 9.3 cm) was used to study the extraction efficiency of

  4. Mechanism of Secondary Hardening in Rapid Tempering of Dual-Phase Steel

    Science.gov (United States)

    Saha, Dulal Chandra; Nayak, Sashank S.; Biro, Elliot; Gerlich, Adrian P.; Zhou, Y.

    2014-12-01

    Dual-phase steel with ferrite-martensite-bainite microstructure exhibited secondary hardening in the subcritical heat affected zone during fiber laser welding. Rapid isothermal tempering conducted in a Gleeble simulator also indicated occurrence of secondary hardening at 773 K (500 °C), as confirmed by plotting the tempered hardness against the Holloman-Jaffe parameter. Isothermally tempered specimens were characterized by analytic transmission electron microscopy and high-angle annular dark-field imaging. The cementite (Fe3C) and TiC located in the bainite phase of DP steel decomposed upon rapid tempering to form needle-shaped Mo2C (aspect ratio ranging from 10 to 25) and plate-shaped M4C3 carbides giving rise to secondary hardening. Precipitation of these thermodynamically stable and coherent carbides promoted the hardening phenomenon. However, complex carbides were only seen in the tempered bainite and were not detected in the tempered martensite. The martensite phase decomposed into ferrite and spherical Fe3C, and interlath-retained austenite decomposed into ferrite and elongated carbide.

  5. Hydrothermal vents in Lake Tanganyika harbor spore-forming thermophiles with extremely rapid growth

    DEFF Research Database (Denmark)

    Elsgaard, Lars; Prieur, Daniel

    2010-01-01

    A thermophilic anaerobic bacterium was isolated from a sublacustrine hydrothermal vent site in Lake Tanganyika (East Africa) with recorded fluid temperatures of 66–103 °C and pH values of 7.7–8.9. The bacterium (strain TR10) was rod-shaped, about 1 by 5 μm in size, and readily formed distal...... and peptone. The optimum temperature for growth was 60 °C, while minimum and maximum temperatures were 40 and 75 °C. The pH response was alkalitolerant with optimum pH at 7.4 and 8.5 depending on the growth medium. The distinct feature of rapid proliferation and endospore formation may allow the novel...

  6. The impact of rapid economic growth and globalization on zinc nutrition in South Korea.

    Science.gov (United States)

    Kwun, In-Sook; Do, Mi-Sook; Chung, Hae-Rang; Kim, Yang Ha; Beattie, John H

    2009-08-01

    Zn deficiency may be widespread in Asian countries such as South Korea. However, dietary habits have changed in response to rapid economic growth and globalization. Zn nutrition in South Koreans has therefore been assessed during a period (1969-1998) of unprecedented economic growth. Cross-sectional food consumption data from the Korean National Nutrition Survey Reports (KNNSR) of South Korea at four separate time points (1969, 1978, 1988 and 1998) were used to calculate Zn, Ca and phytate intakes using various food composition tables, databases and literature values. Nutrient values in local foods were cited from their analysed values. Average Zn intake was 5.8, 4.8 and 5.3 mg/d for 1969, 1978 and 1988 respectively, increasing to 7.3 mg/d in 1998 (73 % of the Korean Dietary Reference Intake). The phytate:Zn molar ratio decreased from 21 to 8 during the study period. Dietary Zn depletion due to marked decreases in cereal consumption, particularly barley which has a low Zn bioavailability, was counterbalanced by marked increases in the consumption of meat and fish, which are also Zn-rich foods. Reduced phytate consumption coincident with increased Zn intake suggests that Zn bioavailability also improved, particularly by 1998. Although total Zn intake was not greatly affected over the initial period of economic growth in South Korea (1969-1988), Zn contributions from different food sources changed markedly and both Zn intake and potential bioavailability were improved by 1998. The study may have implications for Zn nutrition in other Asian countries currently experiencing rapid economic growth.

  7. Pseudobreakup and substorm growth phase in the ionosphere and magnetosphere

    International Nuclear Information System (INIS)

    Koskinin, H.E.J.; Pellinen, R.J.; Pulkkinen, T.I.; Lopez, R.E.; Baker, D.N.; Boesinger, T.

    1993-01-01

    The authors present space and ground based observations made during the growth phase and the onset of a substorm on August 31, 1986. Roughly 20 minutes after the var-epsilon parameter at the magnetopause had exceeded 10 11 W, the AMPTE Charge Composition Explorer spacecraft observed an increase in energetic particle fluxes consistent with magnetic field depolarization. The craft was close to magnetic midnight at a geocentric distance of 8.7R E . The event had the initial signature of a substorm onset, but it did not lead to a full-scale substorm expansion based on several ground based observations. There were no large particle injection events at geostationary orbit. After another 20 minutes the event did enter a normal substorm expansion phase. The authors interpret the initial activation as a open-quotes pseudobreakupclose quotes. They correlate observations made by spacecraft in the near-Earth plasma sheet, with ground based observations of the ionospheric development from magnetometer and electric field measurements from the STARE radar. The strength and the consequences are concluded to be the main differences of pseudobreakups and ordinary breakups

  8. Rapid population growth and fragile environments: the sub-Saharan African and south Asian experience.

    Science.gov (United States)

    Caldwell, J C; Caldwell, P

    1994-02-18

    Case studies of the world's two poorest regions, sub-Saharan Africa and South Asia, were used to illustrate the compromised standard of living of the poor and environmental damage due to continued rapid population growth. The conclusion was that the livelihoods of the poor should not be endangered for preserving the living standards of richer people. Nations must not ignore the challenges of reducing population growth as fast as can be achieved. The transitional period over the next 50 years is the main concern, because population growth rates will be slowing. Rural population growth is expected to decline from 60% of total population growth in South Asia to 7% between 2000 and 2025; similarly the decline in sub-Saharan Africa would be from 50% to 15%. Over the past 30 years, food production in South Asia has kept pace with population growth. Sub-Saharan Africa has adopted food importation to meet demand. African problems are a low resource base, faster population growth, and the fact that governments and individuals are too poor to maintain soil fertility. Long-term studies of how much soil depletion will occur are not available for these regions, and local area studies are not as pessimistic. Transition policies are needed to put "people first in terms of engineered or directed population and ecological change." The six main issues are the following: 1) the Brundtland Commission appropriately identified poverty as the main cause and effect of environmental degradation because of the threat to survival; 2) the verdict is still out about whether food production will keep pace with population growth through economic growth and investment in agriculture; 3) empirical research is needed to examine local social and regulatory institutions and the possibility of reinforcing these mechanisms rather than instituting central controls; 4) central coercion or modernizing economic policies can destroy local level controls; 5) famine is a complex ecological phenomenon and the

  9. Rapid purification of radioiodinated peptides with Sep-Pak reversed phase cartridges and HPLC

    International Nuclear Information System (INIS)

    Miller, J.J.; Schultz, G.S.; Levy, R.S.

    1984-01-01

    A simple, rapid method is described for the purification of radioiodinated peptides for use in radioimmuno- and in radioreceptor assays. Iodinated reaction mixtures are applied directly onto Sep-Pak disposable, reversed phase cartridges equilibrated with phosphate buffer. Unreacted 125-iodide and other non-peptide reaction components are eluted with buffer. The peptide fraction is then eluted with 70% buffer:30% acetonitrile. The peptide fraction is further purified by reversed phase high pressure liquid chromatography to separate the native peptide and the mono- and diiodo-derivatives. In this study the method is used to prepare 125-iodide-labeled monoiodo-leucine enkephalin and monoiodo-angiotensin II, which are free of the parent peptides and diiodo-derivatives and are of maximum obtainable specific radioactivity. The usefulness of these labeled peptides in radioimmuno- and radioreceptor assays is demonstrated by their binding to specific antibodies and receptors, respectively. (author)

  10. Incorporating an extended dendritic growth model into the CAFE model for rapidly solidified non-dilute alloys

    International Nuclear Information System (INIS)

    Ma, Jie; Wang, Bo; Zhao, Shunli; Wu, Guangxin; Zhang, Jieyu; Yang, Zhiliang

    2016-01-01

    We have extended the dendritic growth model first proposed by Boettinger, Coriell and Trivedi (here termed EBCT) for microstructure simulations of rapidly solidified non-dilute alloys. The temperature-dependent distribution coefficient, obtained from calculations of phase equilibria, and the continuous growth model (CGM) were adopted in the present EBCT model to describe the solute trapping behaviors. The temperature dependence of the physical properties, which were not used in previous dendritic growth models, were also considered in the present EBCT model. These extensions allow the present EBCT model to be used for microstructure simulations of non-dilute alloys. The comparison of the present EBCT model with the BCT model proves that the considerations of the distribution coefficient and physical properties are necessary for microstructure simulations, especially for small particles with high undercoolings. Finally, the EBCT model was incorporated into the cellular automaton-finite element (CAFE) model to simulate microstructures of gas-atomized ASP30 high speed steel particles that were then compared with experimental results. Both the simulated and experimental results reveal that a columnar dendritic microstructure preferentially forms in small particles and an equiaxed microstructure forms otherwise. The applications of the present EBCT model provide a convenient way to predict the microstructure of non-dilute alloys. - Highlights: • A dendritic growth model was developed considering non-equilibrium distribution coefficient. • The physical properties with temperature dependence were considered in the extended model. • The extended model can be used to non-dilute alloys and the extensions are necessary in small particles. • Microstructure of ASP30 steel was investigated using the present model and verified by experiment.

  11. Incorporating an extended dendritic growth model into the CAFE model for rapidly solidified non-dilute alloys

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Jie; Wang, Bo [State Key Laboratory of Advanced Special Steel, Shanghai University, Shanghai 200072 (China); Shanghai Engineering Technology Research Center of Special Casting, Shanghai 201605 (China); Zhao, Shunli [Research Institute, Baoshan Iron & Steel Co., Ltd, Shanghai 201900 (China); Wu, Guangxin [State Key Laboratory of Advanced Special Steel, Shanghai University, Shanghai 200072 (China); Shanghai Engineering Technology Research Center of Special Casting, Shanghai 201605 (China); Zhang, Jieyu, E-mail: zjy6162@staff.shu.edu.cn [State Key Laboratory of Advanced Special Steel, Shanghai University, Shanghai 200072 (China); Shanghai Engineering Technology Research Center of Special Casting, Shanghai 201605 (China); Yang, Zhiliang [State Key Laboratory of Advanced Special Steel, Shanghai University, Shanghai 200072 (China); Shanghai Engineering Technology Research Center of Special Casting, Shanghai 201605 (China)

    2016-05-25

    We have extended the dendritic growth model first proposed by Boettinger, Coriell and Trivedi (here termed EBCT) for microstructure simulations of rapidly solidified non-dilute alloys. The temperature-dependent distribution coefficient, obtained from calculations of phase equilibria, and the continuous growth model (CGM) were adopted in the present EBCT model to describe the solute trapping behaviors. The temperature dependence of the physical properties, which were not used in previous dendritic growth models, were also considered in the present EBCT model. These extensions allow the present EBCT model to be used for microstructure simulations of non-dilute alloys. The comparison of the present EBCT model with the BCT model proves that the considerations of the distribution coefficient and physical properties are necessary for microstructure simulations, especially for small particles with high undercoolings. Finally, the EBCT model was incorporated into the cellular automaton-finite element (CAFE) model to simulate microstructures of gas-atomized ASP30 high speed steel particles that were then compared with experimental results. Both the simulated and experimental results reveal that a columnar dendritic microstructure preferentially forms in small particles and an equiaxed microstructure forms otherwise. The applications of the present EBCT model provide a convenient way to predict the microstructure of non-dilute alloys. - Highlights: • A dendritic growth model was developed considering non-equilibrium distribution coefficient. • The physical properties with temperature dependence were considered in the extended model. • The extended model can be used to non-dilute alloys and the extensions are necessary in small particles. • Microstructure of ASP30 steel was investigated using the present model and verified by experiment.

  12. Rapid separation of lanthanides and actinides on small particle based reverse phase supports

    Energy Technology Data Exchange (ETDEWEB)

    Datta, A.; Sivaraman, N.; Srinivasan, T.G.; Vasudeva Rao, P.R. [Chemistry Group, Indira Gandhi Centre for Atomic Research, Kalpakkam (India)

    2010-07-01

    This paper presents the results on the use of short columns (3-5 cm long) with small particle size (1.8 {mu}m) for high performance liquid chromatographic separation of individual lanthanides and uranium from plutonium as well as uranium from thorium to achieve rapid separations i.e. separation time as short as 3.6 min for individual lanthanides, 1 min for thorium-uranium and 4.2 min for uranium from plutonium. These advantages can be exploited to significantly reduce analysis time, liquid waste generation as well as dose to operator when radioactive samples are analysed e.g. burn-up determination. In the present work, a dynamic ion-exchange chromatographic separation technique was employed using camphor-10-sulfonic acid (CSA) as the ion-pairing reagent and {alpha}-hydroxy isobutyric acid ({alpha}-HIBA) as the complexing reagent for the isolation of individual lanthanides as well as the separation of uranium from thorium. Uranium was separated from Pu(III) as well as Pu(IV) by reverse phase HPLC technique. The reverse phase HPLC was also investigated for the isolation and quantitative determination of uranium from thorium as well as lanthanide group from uranium. The dynamic ion-exchange technique using small particle support was demonstrated for measuring the concentrations of lanthanide fission products such as La, Ce, Pr, Nd and Sm in the dissolver solution of fast reactor fuel. Similarly, the assay of uranium in the dissolver solution of fast reactor was carried out using reverse phase HPLC technique. The rapid separation technique using reverse phase HPLC was also demonstrated for separation of lanthanides as a group from uranium matrix; samples of LiCl-KCl eutectic salt containing chlorides of lanthanides in uranium matrix (typically 1: 2000) were analysed. (orig.)

  13. Water hammer due to rapid bubble growth at a severe accident

    International Nuclear Information System (INIS)

    Aya, Izuo; Adachi, Masaki; Shiozaki, Koki; Inasaka, Fujio

    2000-01-01

    On a severe accident of the light water reactor (LWR), by steam explosion and so forth due to hydrogen formation by water-metal reaction and direct contact of molted core with water, it is presumed that a lot of vapor forms for a short time in water at reactor vessel and under part of containment vessel. This study aims at and carries out, under reference of the conventional study results, experimental elucidation on coherence of water block motion due to rapid bubble growth, proposal on reduction method of water hammering, development of water hammer estimating method in an actual reactor, and proposal for upgrading of reliability on severe accident evaluation. In 1998 fiscal year, an 'Experimental apparatus on water hammering elements on sever accident' simulated rapid bubble growth due to steam explosion by injecting high pressure air into water was produced to carry out its function test. As a result of the carried out function tests, extreme water hammering phenomena were observed, by which validity of establishment on the study objects could be confirmed. (G.K.)

  14. Diffuse-interface model for rapid phase transformations in nonequilibrium systems.

    Science.gov (United States)

    Galenko, Peter; Jou, David

    2005-04-01

    A thermodynamic approach to rapid phase transformations within a diffuse interface in a binary system is developed. Assuming an extended set of independent thermodynamic variables formed by the union of the classic set of slow variables and the space of fast variables, we introduce finiteness of the heat and solute diffusive propagation at the finite speed of the interface advancing. To describe transformations within the diffuse interface, we use the phase-field model which allows us to follow steep but smooth changes of phase within the width of the diffuse interface. Governing equations of the phase-field model are derived for the hyperbolic model, a model with memory, and a model of nonlinear evolution of transformation within the diffuse interface. The consistency of the model is proved by the verification of the validity of the condition of positive entropy production and by outcomes of the fluctuation-dissipation theorem. A comparison with existing sharp-interface and diffuse-interface versions of the model is given.

  15. Characterization of rapid recovery from γ-ray damage in plateau-phase human diploid fibroblasts

    International Nuclear Information System (INIS)

    Malcolm, A.W.; Tomkinson, K.N.; Little, J.B.

    1982-01-01

    Rapid recovery was investigated in density-inhibited, stationary-phase human diploid cells subcultured to low density at various times after a single dose of radiation. The influence of total dose, postirradiation temperature, and cell-to-cell contact on recovery was examined. The cultures were exposed to 60 Co γ rays at a dose rate of 50 rad per second. When the irradiation and postirradiation temperatures were maintained at 25 or 37 0 C, recovery, as manifested by an enhancement in survival, was similar during the first 30 min, whereas it was reduced at later times in the 25 0 C compared with the 37 0 C cultures. This result suggests the existence of different rapidly and slowly acting components to recovery. No recovery was noted at any time with incubation at 4 0 C. The recovery observed in density-inhibited cultures was consistently greater than that in less dense cultures, suggesting an effect of cell-to-cell contact and cell cycle distribution. Following single doses of 200 to 900 rad, progressive enhancement in relative recovery occurred with increasing doses over a period of 2 to 90 min, illustrating the importance of the relationship of the dose to the rapid recovery process

  16. Two-dimensional time-resolved x-ray diffraction study of dual phase rapid solidification in steels

    Science.gov (United States)

    Yonemura, Mitsuharu; Osuki, Takahiro; Terasaki, Hidenori; Komizo, Yuichi; Sato, Masugu; Toyokawa, Hidenori; Nozaki, Akiko

    2010-01-01

    The high intensity heat source used for fusion welding creates steep thermal gradients of 100 °C/s from 1800 °C. Further, the influence of preferred orientation is important for the observation of a directional solidification that follows the dendrite growth along the ⟨100⟩ direction toward the moving heat source. In the present study, we observed the rapid solidification of weld metal at a time resolution of 0.01-0.1 s by a two-dimensional time-resolved x-ray diffraction (2DTRXRD) system for real welding. The diffraction rings were dynamically observed by 2DTRXRD with synchrotron energy of 18 keV while the arc passes over the irradiation area of the x-rays. The arc power output was 10 V-150 A, and the scan speed of the arc was 1.0 mm/s. The temperature rise in instruments was suppressed by a water-cooled copper plate under the specimen. Further, the temperature distribution of the weld metal was measured by a thermocouple and correlated with the diffraction patterns. Consequently, solidification and solid phase transformation of low carbon steels and stainless steels were observed during rapid cooling by 2DTRXRD. In the low carbon steel, the microstructure is formed in a two step process, (i) formation of crystallites and (ii) increase of crystallinity. In stainless steel, the irregular interface layer of δ/γ in the quenched metal after solidification is expected to show the easy movement of dendrites at a lower temperature. In carbide precipitation stainless steel, it is easy for NbC to grow on δ phase with a little undercooling. Further, a mistlike pattern, which differs from the halo pattern, in the fusion zone gave some indication of the possibilities to observe the nucleation and the early solidification by 2DTRXRD.

  17. Association of malignancy with rapid growth in early lesions induced by irradiation of rat skin

    International Nuclear Information System (INIS)

    McGregor, J.F.

    1979-01-01

    Epithelial lesions induced by irradiation of rat skin were studied to determine (a) the relationship of malignancy to dose, (b) the types of lesions and circumstances leading to overt malignancy, and (c) the growth rates of lesions progressing to malignancy versus those of lesions remaining benign. High doses of radiation were shown to be associated with the production of epidermal cancers, the maximum yield being obtained at 6,400 rads. Conversely, a peak yield of noncancerous lesions was obtained at 1,600 rads. This association between malignancy and high dose was consistent for cancers evolving from warts, cysts, and chronic ulcers. Although the proportion of warts among the induced lesions was much higher than that of the cysts or chronic ulcers (76, 14, and 10%, respectively), the likelihood of warts becoming cancerous was substantially lower (14, 23, and 21%). The combined data for all doses showed that the latency period of the epidermal cancers was significantly (P = 0.015) shorter than that of the benign tumors. Rapid growth rates were observed for warts, cysts, and chronic ulcers progressing to overt cancer, and these did not overlap at any point on the growth scale with rates for benign tumors. This finding suggested that the potential for malignant development had been established early in the carcinogenic process, very likely at induction

  18. Rapid growth in nitrogen dioxide pollution over Western China, 2005-2013

    Science.gov (United States)

    Cui, Yuanzheng; Lin, Jintai; Song, Chunqiao; Liu, Mengyao; Yan, Yingying; Xu, Yuan; Huang, Bo

    2016-05-01

    Western China has experienced rapid industrialization and urbanization since the implementation of the National Western Development Strategies (the "Go West" movement) in 1999. This transition has affected the spatial and temporal characteristics of nitrogen dioxide (NO2) pollution. In this study, we analyze the trends and variability of tropospheric NO2 vertical column densities (VCDs) from 2005 to 2013 over Western China, based on a wavelet analysis on monthly mean NO2 data derived from the Ozone Monitoring Instrument (OMI) measurements. We focus on the anthropogenic NO2 by subtracting region-specific "background" values dominated by natural sources. After removing the background influences, we find significant anthropogenic NO2 growth over Western China between 2005 and 2013 (8.6 ± 0.9 % yr-1 on average, relative to 2005), with the largest increments (15 % yr-1 or more) over parts of several city clusters. The NO2 pollution in most provincial-level regions rose rapidly from 2005 to 2011 but stabilized or declined afterwards. The NO2 trends were driven mainly by changes in anthropogenic emissions, as confirmed by a nested GEOS-Chem model simulation and a comparison with Chinese official emission statistics. The rate of NO2 growth during 2005-2013 reaches 11.3 ± 1.0 % yr-1 over Northwestern China, exceeding the rates over Southwestern China (5.9 ± 0.6 % yr-1) and the three well-known polluted regions in the east (5.3 ± 0.8 % yr-1 over Beijing-Tianjin-Hebei, 4.0 ± 0.6 % yr-1 over the Yangtze River Delta, and -3.3 ± 0.3 % yr-1 over the Pearl River Delta). Subsequent socioeconomic analyses suggest that the rapid NO2 growth over Northwestern China is likely related to the fast developing resource- and pollution-intensive industries along with the "Go West" movement as well as relatively weak emission controls. Further efforts should be made to alleviate NOx pollution to achieve sustainable development in Western China.

  19. Rapid growth in nitrogen dioxide pollution over Western China, 2005-2013

    Science.gov (United States)

    Cui, Y.-Z.; Lin, J.-T.; Song, C.; Liu, M.-Y.; Yan, Y.-Y.; Xu, Y.; Huang, B.

    2015-12-01

    Western China has experienced rapid industrialization and urbanization since the implementation of the National Western Development Strategies (the "Go West" movement) in 1999. This transition has affected the spatial and temporal characteristics of nitrogen dioxide (NO2) pollution. In this study, we analyze the trends and variability of tropospheric NO2 vertical column densities (VCDs) from 2005 to 2013 over Western China, based on a wavelet analysis on monthly mean NO2 data derived from the Ozone Monitoring Instrument (OMI) measurements. We focus on the anthropogenic NO2 by subtracting region-specific "background" values dominated by natural sources. We find significant NO2 growth over Western China between 2005 and 2013 (8.6 ± 0.9 % yr-1 on average, relative to 2005), with the largest increments (15 % yr-1 or more) over parts of several city clusters. The NO2 pollution in most provincial regions rose rapidly from 2005 to 2011 but stabilized or declined afterwards. The NO2 trends were driven mainly by changes in anthropogenic emissions, as confirmed by a nested GEOS-Chem model simulation and a comparison with Chinese official emission statistics. The rate of NO2 growth during 2005-2013 reaches 11.3 ± 1.0 % yr-1 over Northwestern China, exceeding the rates over Southwestern China (5.9 ± 0.6 % yr-1) and the three well-known polluted regions in the east (5.3 ± 0.8 % yr-1 over Beijing-Tianjin-Hebei, 4.0 ± 0.6 % yr-1} over the Yangtze River Delta, and -3.3 ± 0.3 % yr-1 over the Pearl River Delta). Additional socioeconomic analyses suggest that the rapid NO2 growth in Northwestern China is likely related to the fast developing resource- and pollution-intensive industries along with the "Go West" movement as well as relatively weak emission controls. Further efforts should be made to alleviate NOx pollution to achieve sustainable development in Western China.

  20. A decade of rapid change: Biocultural influences on child growth in highland Peru.

    Science.gov (United States)

    Oths, Kathryn S; Smith, Hannah N; Stein, Max J; Lazo Landivar, Rodrigo J

    2018-03-01

    In the past decade many areas of Peru have been undergoing extreme environmental, economic, and cultural change. In the highland hamlet of Chugurpampa, La Libertad, climate change has ruined harvests and led to frequent periods of migration to the coast in search of livelihood. This biocultural research examines how the changes could be affecting the growth of children who maintain residence in the highlands. Clinical records from the early 2000s were compared to those from the early 2010s. Charts were randomly selected to record anthropometric data, netting a sample of 75 children ages 0-60 months of age. Analysis of covariance was run to compare mean stature, weight, and BMI between cohorts. Percentage of children who fall below the -2 threshold for z-scores for height and weight were compared by age and cohort. A significant secular trend in growth was found, with children born more recently larger than those born a decade before. The effect is most notable in the first year of life, with the growth advantage attenuated by the age of 3 for height and age 4 for weight. While children were unlikely to be stunted from 0 to 3 years of age, 44% of the later cohort were stunted and 11% were underweight from 4 to 5 years of age. Three possible explanations for the rapid shift are entertained: more time spent on the coast during gestation and early childhood, which may attenuate the effect of hypoxia on child growth; dietary change; and increased use of biomedicine. © 2017 Wiley Periodicals, Inc.

  1. On the mechanism of rapid postirradiation recovery of yeast

    International Nuclear Information System (INIS)

    Glazunov, A.V.; Kapul'tsevich, Yu.G.

    1983-01-01

    Rapid postirradiation recovery of diploid yeast Saccharomyces cerevisiae is equally effective both in water and in a liquid nutrition medium. In the haploid strains, rapid recovery occurs more readily in the log phase than in the stationary phase of growth. In the diploid strains, rapid recovery is more effective in the log phase than in the stationary phase. Rapid recovery of yeast does not require an additional protein synthesis. Damages induced by UV-light are not sub ected to rapid recovery

  2. Prenatal bisphenol a urine concentrations and early rapid growth and overweight risk in the offspring.

    Science.gov (United States)

    Valvi, Damaskini; Casas, Maribel; Mendez, Michelle A; Ballesteros-Gómez, Ana; Luque, Noelia; Rubio, Soledad; Sunyer, Jordi; Vrijheid, Martine

    2013-11-01

    Increasing experimental evidence suggests that prenatal bisphenol A (BPA) exposure induces offspring weight gain, but these effects remain largely unexplored in humans. We examined the effects of prenatal BPA exposure on postnatal growth and obesity. BPA concentrations were measured in two spot-urine samples collected in the 1st and 3rd trimesters of pregnancy from mothers in a Spanish birth cohort study (n = 402). We used the average of the two creatinine-adjusted BPA concentrations as the exposure variable. Rapid child growth was defined as a weight gain Z score >0.67 in the first 6 months of life. Age- and sex-specific Z scores for body mass index (BMI) were calculated at age 14 months and 4 years, based on the World Health Organization referent; overweight was defined as a BMI Z score greater than or equal to the 85th percentile. Age- and sex-specific waist circumference Z scores were calculated at age 14 months and 4 years using the analysis population mean. Twenty-six percent of children were rapid growers; 25% were overweight at 14 months and 21% at 4 years. Geometric mean BPA concentrations were 2.6 μg/g creatinine (standard deviation = 2.3) in 1st trimester and 2.0 (2.3) in 3rd trimester samples (Pearson r = 0.13). At 4 years, BPA exposure was associated with increased waist circumference (β per log10 μg/g = 0.28 [95% confidence interval = 0.01 to 0.57]) and BMI (β = 0.28 [-0.06 to 0.63]). BPA was not associated with obesity-related outcomes at earlier ages. This study provides some evidence for an association between prenatal BPA exposure and obesity-related outcomes in childhood, although not in infancy. The large uncertainties in BPA exposure assessment require that findings be interpreted with caution.

  3. Rapid growth of single-layer graphene on the insulating substrates by thermal CVD

    Energy Technology Data Exchange (ETDEWEB)

    Chen, C.Y. [Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming 650093 (China); Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Dai, D.; Chen, G.X.; Yu, J.H. [Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Nishimura, K. [Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Advanced Nano-processing Engineering Lab, Mechanical Systems Engineering, Kogakuin University (Japan); Lin, C.-T. [Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Jiang, N., E-mail: jiangnan@nimte.ac.cn [Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Zhan, Z.L., E-mail: zl_zhan@sohu.com [Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming 650093 (China)

    2015-08-15

    Highlights: • A rapid thermal CVD process has been developed to directly grow graphene on the insulating substrates. • The treating time consumed is ≈25% compared to conventional CVD procedure. • Single-layer and few-layer graphene can be formed on quartz and SiO{sub 2}/Si substrates, respectively. • The formation of thinner graphene at the interface is due to the fast precipitation rate of carbon atoms during cooling. - Abstract: The advance of CVD technique to directly grow graphene on the insulating substrates is particularly significant for further device fabrication. As graphene is catalytically grown on metal foils, the degradation of the sample properties is unavoidable during transfer of graphene on the dielectric layer. Moreover, shortening the treatment time as possible, while achieving single-layer growth of graphene, is worthy to be investigated for promoting the efficiency of mass production. Here we performed a rapid heating/cooling process to grow graphene films directly on the insulating substrates by thermal CVD. The treating time consumed is ≈25% compared to conventional CVD procedure. In addition, we found that high-quality, single-layer graphene can be formed on quartz, but on SiO{sub 2}/Si substrate only few-layer graphene can be obtained. The pronounced substrate effect is attributed to the different dewetting behavior of Ni films on the both substrates at 950 °C.

  4. Phase composition and properties of rapidly cooled aluminium-zirconium-chromium alloys

    International Nuclear Information System (INIS)

    Sokolovskaya, E.M.; Badalova, L.M.; Podd''yakova, E.I.; Kazakova, E.F.; Loboda, T.P.; Gribanov, A.V.

    1989-01-01

    Using the methods of physicochemical analysis the interaction of aluminium with zirconium and chromium is studied. Polythermal cross sections between Al 3 -Zr-Al 7 Cr and radial polythermal cross section from aluminium-rich corner with the ratio of components Zr:Cr=5:7 by mass are constructed. The effect of zirconium and chromium content on electrochemical characteristics of aluminium-base rapidly quenching alloys in systems Al-Cr, Al-Zr, Al-Cr-Zr. An increase in chromium concentration in oversaturated solid solution of Al-Cr system expands considerably the range of passive state. When Al 7 Cr phase appears the range of passive stae vanishes

  5. Quantum state engineering with flux-biased Josephson phase qubits by rapid adiabatic passages

    Science.gov (United States)

    Nie, W.; Huang, J. S.; Shi, X.; Wei, L. F.

    2010-09-01

    In this article, the scheme of quantum computing based on the Stark-chirped rapid adiabatic passage (SCRAP) technique [L. F. Wei, J. R. Johansson, L. X. Cen, S. Ashhab, and F. Nori, Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.100.113601 100, 113601 (2008)] is extensively applied to implement quantum state manipulations in flux-biased Josephson phase qubits. The broken-parity symmetries of bound states in flux-biased Josephson junctions are utilized to conveniently generate the desirable Stark shifts. Then, assisted by various transition pulses, universal quantum logic gates as well as arbitrary quantum state preparations can be implemented. Compared with the usual π-pulse operations widely used in experiments, the adiabatic population passages proposed here are insensitive to the details of the applied pulses and thus the desirable population transfers can be satisfyingly implemented. The experimental feasibility of the proposal is also discussed.

  6. Quantum state engineering with flux-biased Josephson phase qubits by rapid adiabatic passages

    International Nuclear Information System (INIS)

    Nie, W.; Huang, J. S.; Shi, X.; Wei, L. F.

    2010-01-01

    In this article, the scheme of quantum computing based on the Stark-chirped rapid adiabatic passage (SCRAP) technique [L. F. Wei, J. R. Johansson, L. X. Cen, S. Ashhab, and F. Nori, Phys. Rev. Lett. 100, 113601 (2008)] is extensively applied to implement quantum state manipulations in flux-biased Josephson phase qubits. The broken-parity symmetries of bound states in flux-biased Josephson junctions are utilized to conveniently generate the desirable Stark shifts. Then, assisted by various transition pulses, universal quantum logic gates as well as arbitrary quantum state preparations can be implemented. Compared with the usual π-pulse operations widely used in experiments, the adiabatic population passages proposed here are insensitive to the details of the applied pulses and thus the desirable population transfers can be satisfyingly implemented. The experimental feasibility of the proposal is also discussed.

  7. Rapid determination of ions by combined solid-phase extraction--diffuse reflectance spectroscopy

    Science.gov (United States)

    Fritz, James S.; Arena, Matteo P.; Steiner, Steven A.; Porter, Marc D.

    2003-01-01

    We introduce colorimetric solid-phase extraction (C-SPE) for the rapid determination of selected ions. This new technique links the exhaustive concentration of an analyte by SPE onto a membrane disk surface for quantitative measurement with a hand-held diffuse reflectance spectrometer. The concentration/measurement procedure is complete in approximately 1 min and can be performed almost anywhere. This method has been used to monitor iodine and iodide in spacecraft water in the 0.1-5.0 ppm range and silver(I) in the range of 5.0-1000 microg/l. Applications to the trace analysis of copper(II), nickel(II), iron(III) and chromium(VI) are described. Studies on the mechanism of extraction showed that impregnation of the disk with a surfactant as well as a complexing reagent results in uptake of additional water, which markedly improves the extraction efficiency.

  8. Rapid experimental SAD phasing and hot-spot identification with halogenated fragments

    Directory of Open Access Journals (Sweden)

    Joseph D. Bauman

    2016-01-01

    Full Text Available Through X-ray crystallographic fragment screening, 4-bromopyrazole was discovered to be a `magic bullet' that is capable of binding at many of the ligand `hot spots' found in HIV-1 reverse transcriptase (RT. The binding locations can be in pockets that are `hidden' in the unliganded crystal form, allowing rapid identification of these sites for in silico screening. In addition to hot-spot identification, this ubiquitous yet specific binding provides an avenue for X-ray crystallographic phase determination, which can be a significant bottleneck in the determination of the structures of novel proteins. The anomalous signal from 4-bromopyrazole or 4-iodopyrazole was sufficient to determine the structures of three proteins (HIV-1 RT, influenza A endonuclease and proteinase K by single-wavelength anomalous dispersion (SAD from single crystals. Both compounds are inexpensive, readily available, safe and very soluble in DMSO or water, allowing efficient soaking into crystals.

  9. Retrieving 3D Wind Field from Phased Array Radar Rapid Scans

    Directory of Open Access Journals (Sweden)

    Xiaobin Qiu

    2013-01-01

    Full Text Available The previous two-dimensional simple adjoint method for retrieving horizontal wind field from a time sequence of single-Doppler scans of reflectivity and/or radial velocity is further developed into a new method to retrieve both horizontal and vertical winds at high temporal and spatial resolutions. This new method performs two steps. First, the horizontal wind field is retrieved on the conical surface at each tilt (elevation angle of radar scan. Second, the vertical velocity field is retrieved in a vertical cross-section along the radar beam with the horizontal velocity given from the first step. The method is applied to phased array radar (PAR rapid scans of the storm winds and reflectivity in a strong microburst event and is shown to be able to retrieve the three-dimensional wind field around a targeted downdraft within the storm that subsequently produced a damaging microburst. The method is computationally very efficient and can be used for real-time applications with PAR rapid scans.

  10. Weed diversity identification on growth phases of twelve maize varieties

    Science.gov (United States)

    Rahayu, M.; Yudono, P.; Indradewa, D.; Hanudin, E.

    2018-03-01

    Weed is one of the factors that disturb maize cultivation. Each maize variety has specific characteristics which will lead to weeds diversity in particular farm. This study aimed to identify the effect of maize variety on weed diversity on maize’s growth phases. The research was conducted from March to July 2016 in Banguntapan, Bantul, Yogyakarta, Indonesia. The field research was arranged by using Randomised Complete Block Design with three replications. The treatments were maize varieties, consist of 12 levels: ‘Bisi 18’, ‘Bisi 2’, ‘Pertiwi 3’, ‘NK 22’, ‘NK 33’, ‘DK 959’, ‘P23’, ‘DK 771’, ‘DK 95’, ‘Bima 19 Uri’, ‘Bisma’, and ‘Sukmaraga’. The results showed that at four weeks after planting (WAP) the most of weeds were growing on varieties ‘Bisi 18’, ‘NK 33’, ‘P 23’, and ‘DK 95’, there were 14 species. Bulbostylispuberula and Cyperusrotundus were growing on all maize varieties with the highest SDR on ‘Sukmaraga’ and ‘DK 959’. At six WAP, weeds that grew, most consists of four species of sedges, six species of grasses and 24 species of broadleaf. While at the age of eight WAP, the weeds that grow at least on ‘NK 33’ that were 13 species and the most on ‘P23’ that were 21 species. Dactyloctenium aeghypthium having highest SDR in all maize varieties except Bisi 18. The highest SDR value on Bisi 18 was Boerhaavia erecta about 16.23%.

  11. Phase formation kinetics, hardness and magnetocaloric effect of sub-rapidly solidified LaFe11.6Si1.4 plates during isothermal annealing

    Science.gov (United States)

    Dai, Yuting; Xu, Zhishuai; Luo, Zhiping; Han, Ke; Zhai, Qijie; Zheng, Hongxing

    2018-05-01

    High-temperature phase transition behavior and intrinsic brittleness of NaZn13-type τ1 phase in La-Fe-Si magnetocaloric materials are two key problems from the viewpoint of materials production and practical applications. In the present work, the Johnson-Mehl-Avrami-Kolmogorov (JMAK) equation was introduced to quantitatively characterize the formation kinetics of τ1 phase in sub-rapidly solidified LaFe11.6Si1.4 plates during the isothermal annealing process. Avrami index was estimated to be 0.43 (∼0.5), which suggests that the formation of τ1 phase is in a diffusion-controlled one-dimensional growth mode. Meanwhile, it is found that the Vickers hardness as a function of annealing time for sub-rapidly solidified plates also agrees well with the JMAK equation. The Vickers hardness of τ1 phase was estimated to be about 754. Under a magnetic field change of 30 kOe, the maximum magnetic entropy change was about 22.31 J/(kg·K) for plates annealed at 1323 K for 48 h, and the effective magnetic refrigeration capacity reached 191 J/kg.

  12. Rapid determination of human globin chains using reversed-phase high-performance liquid chromatography.

    Science.gov (United States)

    Wan, Jun-Hui; Tian, Pei-Ling; Luo, Wei-Hao; Wu, Bing-Yi; Xiong, Fu; Zhou, Wan-Jun; Wei, Xiang-Cai; Xu, Xiang-Min

    2012-07-15

    Reversed-phase high-performance liquid chromatography (RP-HPLC) of human globin chains is an important tool for detecting thalassemias and hemoglobin variants. The challenges of this method that limit its clinical application are a long analytical time and complex sample preparation. The aim of this study was to establish a simple, rapid and high-resolution RP-HPLC method for the separation of globin chains in human blood. Red blood cells from newborns and adults were diluted in deionized water and injected directly onto a micro-jupiter C18 reversed-phase column (250 mm × 4.6 mm) with UV detection at 280 nm. Under the conditions of varying pH or the HPLC gradient, the globin chains (pre-β, β, δ, α, (G)γ and (A)γ) were denatured and separated from the heme groups in 12 min with a retention time coefficient of variation (CV) ranging from 0.11 to 1.29% and a peak area CV between 0.32% and 4.86%. Significant differences (P<0.05) among three groups (normal, Hb H and β thalassemia) were found in the area ratio of α/pre-β+β applying the rapid elution procedure, while P≥0.05 was obtained between the normal and α thalassemia silent/trait group. Based on the ANOVA results, receiver operating characteristic (ROC) curve analysis of the δ/β and α/pre-β+β area ratios showed a sensitivity of 100.0%, and a specificity of 100.0% for indicating β thalassemia carriers, and a sensitivity of 96.6% and a specificity of 89.6% for the prediction of hemoglobin H (Hb H) disease. The proposed cut-off was 0.026 of δ/β for β thalassemia carriers and 0.626 of α/pre-β+β for Hb H disease. In addition, abnormal hemoglobin hemoglobin E (Hb E) and Hb Westmead (Hb WS) were successfully identified using this RP-HPLC method. Our experience in developing this RP-HPLC method for the rapid separation of human globin chains could be of use for similar work. Copyright © 2012 Elsevier B.V. All rights reserved.

  13. Diffusion-stress coupling in liquid phase during rapid solidification of binary mixtures

    International Nuclear Information System (INIS)

    Sobolev, S.L.

    2014-01-01

    An analytical model has been developed to describe the diffusion-viscous stress coupling in the liquid phase during rapid solidification of binary mixtures. The model starts with a set of evolution equations for diffusion flux and viscous pressure tensor, based on extended irreversible thermodynamics. It has been demonstrated that the diffusion-stress coupling leads to non-Fickian diffusion effects in the liquid phase. With only diffusive dynamics, the model results in the nonlocal diffusion equations of parabolic type, which imply the transition to complete solute trapping only asymptotically at an infinite interface velocity. With the wavelike dynamics, the model leads to the nonlocal diffusion equations of hyperbolic type and describes the transition to complete solute trapping and diffusionless solidification at a finite interface velocity in accordance with experimental data and molecular dynamic simulation. -- Highlights: •We propose the diffusion-stress coupling model for binary solidification. •The coupling arises at deep undercooling. •With diffusive dynamics, the models result in parabolic transfer equations. •With the wavelike dynamics, the models lead to hyperbolic transfer equations. •The coupling strongly affects the solute partition coefficient

  14. A scheme for reducing deceleration-phase Rayleigh-Taylor growth in inertial confinement fusion implosions

    Science.gov (United States)

    Wang, L. F.; Ye, W. H.; Wu, J. F.; Liu, Jie; Zhang, W. Y.; He, X. T.

    2016-05-01

    It is demonstrated that the growth of acceleration-phase instabilities in inertial confinement fusion implosions can be controlled, especially in the high-foot implosions [O. A. Hurricane et al., Phys. Plasmas 21, 056314 (2014)] on the National Ignition Facility. However, the excessive growth of the deceleration-phase instabilities can still destroy the hot spot ignition. A scheme is proposed to retard the deceleration-phase Rayleigh-Taylor instability growth by shock collision near the waist of the inner shell surface. Two-dimensional radiation hydrodynamic simulations confirm the improved deceleration-phase hot spot stability properties without sacrificing the fuel compression.

  15. A scheme for reducing deceleration-phase Rayleigh–Taylor growth in inertial confinement fusion implosions

    Energy Technology Data Exchange (ETDEWEB)

    Wang, L. F., E-mail: wang-lifeng@iapcm.ac.cn; Ye, W. H.; Liu, Jie [Institute of Applied Physics and Computational Mathematics, Beijing 100094 (China); HEDPS, Center for Applied Physics and Technology, Peking University, Beijing 100871 (China); Center for Fusion Energy Science and Technology, Chinese Academy of Engineering Physics, Beijing 100088 (China); Wu, J. F. [Institute of Applied Physics and Computational Mathematics, Beijing 100094 (China); Center for Fusion Energy Science and Technology, Chinese Academy of Engineering Physics, Beijing 100088 (China); Zhang, W. Y. [Institute of Applied Physics and Computational Mathematics, Beijing 100094 (China); He, X. T. [Institute of Applied Physics and Computational Mathematics, Beijing 100094 (China); HEDPS, Center for Applied Physics and Technology, Peking University, Beijing 100871 (China)

    2016-05-15

    It is demonstrated that the growth of acceleration-phase instabilities in inertial confinement fusion implosions can be controlled, especially in the high-foot implosions [O. A. Hurricane et al., Phys. Plasmas 21, 056314 (2014)] on the National Ignition Facility. However, the excessive growth of the deceleration-phase instabilities can still destroy the hot spot ignition. A scheme is proposed to retard the deceleration-phase Rayleigh–Taylor instability growth by shock collision near the waist of the inner shell surface. Two-dimensional radiation hydrodynamic simulations confirm the improved deceleration-phase hot spot stability properties without sacrificing the fuel compression.

  16. Pulsating aurora and cosmic noise absorption associated with growth-phase arcs

    Directory of Open Access Journals (Sweden)

    D. McKay

    2018-01-01

    Full Text Available The initial stage of a magnetospheric substorm is the growth phase, which typically lasts 1–2 h. During the growth phase, an equatorward moving, east–west extended, optical auroral arc is observed. This is called a growth-phase arc. This work aims to characterize the optical emission and riometer absorption signatures associated with growth-phase arcs of isolated substorms. This is done using simultaneous all-sky camera and imaging riometer observations. The optical and riometric observations allow determination of the location of the precipitation within growth-phase arcs of low- (< 10  keV and high- (>  10 keV energy electrons, respectively. The observations indicate that growth-phase arcs have the following characteristics: 1. The peak of the cosmic noise absorption (CNA arc is equatorward of the optical emission arc. This CNA is contained within the region of diffuse aurora on the equatorward side.2. Optical pulsating aurora are seen in the border region between the diffuse emission region on the equatorward side and the bright growth-phase arc on the poleward side. CNA is detected in the same region. 3. There is no evidence of pulsations in the CNA. 4. Once the equatorward drift starts, it proceeds at constant speed, with uniform separation between the growth-phase arc and CNA of 40 ± 10 km. Optical pulsating aurora are known to be prominent in the post-onset phase of a substorm. The fact that pulsations are also seen in a fairly localized region during the growth phase shows that the substorm expansion-phase dynamics are not required to closely precede the pulsating aurora.

  17. Rapid hydrothermal route to synthesize cubic-phase gadolinium oxide nanorods

    International Nuclear Information System (INIS)

    Hazarika, Samiran; Paul, Nibedita; Mohanta, Dambarudhar

    2014-01-01

    An inexpensive fabrication route and growth mechanism is being reported for obtaining quality gadolinium oxide ( Gd 2 O 3 ) nanoscale rods. The elongated nanoscale systems, as produced via a hydrothermal process, were characterized by X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), optical absorption spectroscopy, photoluminescence (PL) spectroscopy, Raman spectroscopy and magnetic hysteresis measurements. XRD patterns of the nanorods, as-prepared from independent precursors of different pH, depict a cubic crystal phase and an average crystallite size of 5-6.5 nm. As revealed from HRTEM micrographs, diameter of the nanorods prepared at pH = 13.3 (∼7 nm) was much smaller than the rods prepared at pH = 10.8 (∼19 nm). However, the aspect ratio was more than double in the former case than the latter case. PL response was found to be dominated by defect mediated emissions, whereas Raman spectrum of a given specimen (pH = 10.8) has revealed characteristic F g + A g modes of cubic phase of Gd 2 O 3 nanorods, apart from other independent modes. Furthermore, M ∼ H plot of the nanorod system (pH = 10.8) exhibited slight departure from the ideal superparamagnetic behaviour, with low remanence and coercive field values. The exploitation of one-dimensional Gd 2 O 3 nanorods have immense potential in the production of advanced contrast agents, smart drives and also in making novel ferrofluids of technological relevance. (author)

  18. The Seneca effect why growth is slow but collapse is rapid

    CERN Document Server

    Bardi, Ugo

    2017-01-01

    The essence of this book can be found in a line written by the ancient Roman Stoic Philosopher Lucius Annaeus Seneca: "Fortune is of sluggish growth, but ruin is rapid". This sentence summarizes the features of the phenomenon that we call "collapse," which is typically sudden and often unexpected, like the proverbial "house of cards." But why are such collapses so common, and what generates them? Several books have been published on the subject, including the well-known "Collapse" by Jared Diamond (2005), "The collapse of complex societies" by Joseph Tainter (1998) and "The Tipping Point," by Malcom Gladwell (2000). Why The Seneca Effect? This book is an ambitious attempt to pull these various strands together by describing collapse from a multi-disciplinary viewpoint. The reader will discover how collapse is a collective phenomenon that occurs in what we call today "complex systems," with a special emphasis on system dynamics and t he concept of "feedback." From this foundation, Bardi applies the...

  19. Rapid Startup and Loading of an Attached Growth, Simultaneous Nitrification/Denitrification Membrane Aerated Bioreactor

    Science.gov (United States)

    Meyer, Caitlin; Vega, Leticia

    2014-01-01

    The Membrane Aerated Bioreactor (MABR) is an attached-growth biological system for simultaneous nitrification and denitrification. This design is an innovative approach to common terrestrial wastewater treatments for nitrogen and carbon removal. Implementing a biologically-based water treatment system for long-duration human exploration is an attractive, low energy alternative to physiochemical processes. Two obstacles to implementing such a system are (1) the "start-up" duration from inoculation to steady-state operations and (2) the amount of surface area needed for the biological activity to occur. The Advanced Water Recovery Systems (AWRS) team at JSC explored these two issues through two tests; a rapid inoculation study and a wastewater loading study. Results from these tests demonstrate that the duration from inoculation to steady state can be reduced to two weeks and that the surface area to volume ratio baseline used in the Alternative Water Processor (AWP) test was higher than what was needed to remove the organic carbon and ammonium from the system.

  20. Rapid experimental SAD phasing and hot-spot identification with halogenated fragments

    Energy Technology Data Exchange (ETDEWEB)

    Bauman, Joseph D.; Harrison, Jerry Joe E. K.; Arnold, Eddy

    2016-01-01

    Through X-ray crystallographic fragment screening, 4-bromopyrazole was discovered to be a `magic bullet' that is capable of binding at many of the ligand `hot spots' found in HIV-1 reverse transcriptase (RT). The binding locations can be in pockets that are `hidden' in the unliganded crystal form, allowing rapid identification of these sites forin silicoscreening. In addition to hot-spot identification, this ubiquitous yet specific binding provides an avenue for X-ray crystallographic phase determination, which can be a significant bottleneck in the determination of the structures of novel proteins. The anomalous signal from 4-bromopyrazole or 4-iodopyrazole was sufficient to determine the structures of three proteins (HIV-1 RT, influenza A endonuclease and proteinase K) by single-wavelength anomalous dispersion (SAD) from single crystals. Both compounds are inexpensive, readily available, safe and very soluble in DMSO or water, allowing efficient soaking into crystals.

  1. Plant Growth and Development: An Outline for a Unit Structured Around the Life Cycle of Rapid-Cycling Brassica Rapa.

    Science.gov (United States)

    Becker, Wayne M.

    This outline is intended for use in a unit of 10-12 lectures on plant growth and development at the introductory undergraduate level as part of a course on organismal biology. The series of lecture outlines is structured around the life cycle of rapid-cycling Brassica rapa (RCBr). The unit begins with three introductory lectures on general plant…

  2. Growth in Rapid Automatized Naming from Grades K to 8 in Children with Math or Reading Disabilities

    Science.gov (United States)

    Mazzocco, Michèle M. M.; Grimm, Kevin J.

    2013-01-01

    Rapid automatized naming (RAN) is widely used to identify reading disabilities (RD) and has recently been considered a potential predictor of risk for mathematics learning disabilities (MLD). Here we longitudinally examine RAN performance from Grades K to 8, to view how growth on RAN response time differs for children with RD versus MLD. Across…

  3. Bubble nucleation and growth in very strong cosmological phase transitions

    Energy Technology Data Exchange (ETDEWEB)

    Mégevand, Ariel, E-mail: megevand@mdp.edu.ar; Ramírez, Santiago

    2017-06-15

    Strongly first-order phase transitions, i.e., those with a large order parameter, are characterized by a considerable supercooling and high velocities of phase transition fronts. A very strong phase transition may have important cosmological consequences due to the departures from equilibrium caused in the plasma. In general, there is a limit to the strength, since the metastability of the old phase may prevent the transition to complete. Near this limit, the bubble nucleation rate achieves a maximum and thus departs from the widely assumed behavior in which it grows exponentially with time. We study the dynamics of this kind of phase transitions. We show that in some cases a gaussian approximation for the nucleation rate is more suitable, and in such a case we solve analytically the evolution of the phase transition. We compare the gaussian and exponential approximations with realistic cases and we determine their ranges of validity. We also discuss the implications for cosmic remnants such as gravitational waves.

  4. The rapid growth of domestic oil consumption in Saudi Arabia and the opportunity cost of oil exports foregone

    International Nuclear Information System (INIS)

    Gately, Dermot; Al-Yousef, Nourah; Al-Sheikh, Hamad M.H.

    2012-01-01

    We analyze the rapid growth of Saudi Arabia's domestic oil consumption, a nine-fold increase in 40 years, to nearly 3 million barrels per day, about one-fourth of production. Such rapid growth in consumption – 5.7% annually, which is 37% faster than its income growth of 4.2% – will challenge Saudi Arabia's ability to increase its oil exports, which are relied upon in long-term world oil projections by the International Energy Agency (IEA), US Department of Energy (DOE) and British Petroleum (BP). However, these institutions assume unprecedented slowdowns in Saudi oil consumption – from 5.7% annual growth historically to less than 2% in the future – allowing them to project increases in Saudi oil exports. Using 1971–2010 data, we estimate that the income responsiveness (elasticity) of oil consumption is at least 1.5—using both Ordinary Least Squares regression and Cointegration methods. We believe that continued high growth rates for domestic oil consumption are more likely than the dramatic slowdowns projected by IEA, DOE and BP. This will have major implications for Saudi production and export levels. - Highlights: ► We analyze the rapid growth of Saudi Arabia's domestic oil consumption, now one-fourth of production. ► Estimated income elasticity of oil demand at least 1.5, using OLS and Co-integration. ► Yet IEA, DOE and BP project unprecedented slowdowns, from 5.7% historically to below 2%, half the rate of income growth. ► Continued high growth rates are more likely, with major implications for Saudi production and export levels.

  5. Effects of Phytoplankton Growth Phase on the Formation and Properties of Marine Snow

    Science.gov (United States)

    Montgomery, Q. W.; Proctor, K. W.; Prairie, J. C.

    2016-02-01

    Marine snow aggregates often dominate carbon export from the upper mixed layer to the deep ocean. Thus, understanding the formation and the properties of these aggregates is essential to the study of the biological pump. Aggregate formation is determined by both the encounter rate and the stickiness of the particles that they are composed of. Stickiness of phytoplankton has been linked to production of transparent exopolymer particles (TEP), which has been previously shown to vary in concentration throughout different parts of the phytoplankton growth cycle. The objective of this study is to determine the effects of the growth phase of the diatom Thalassiosira weissflogii to both TEP production and the properties of the resulting aggregates produced. Cultures of T. weissflogii were stopped at separate phases of the phytoplankton growth curve and incubated in rotating cylindrical tanks to form aggregates. Aggregate properties such as size, density, and porosity were measured at the end of each period of roller incubation. Preliminary results describe little variation in the size of the aggregates formed from different parts of the growth phase, but show a significant effect of growth phase on aggregate density. Density is an important factor in the settling of marine aggregates. Therefore, variations in aggregate density during different growth phases may have large implications for the efficiency of the biological pump during different stages of a phytoplankton bloom. Further examination will be performed on the potential effects of TEP abundance on the properties of the aggregates formed at separate growth phases and the resulting implications for carbon flux.

  6. Insulin receptors mediate growth effects in cultured fetal neurons. I. Rapid stimulation of protein synthesis

    International Nuclear Information System (INIS)

    Heidenreich, K.A.; Toledo, S.P.

    1989-01-01

    In this study we have examined the effects of insulin on protein synthesis in cultured fetal chick neurons. Protein synthesis was monitored by measuring the incorporation of [3H]leucine (3H-leu) into trichloroacetic acid (TCA)-precipitable protein. Upon addition of 3H-leu, there was a 5-min lag before radioactivity occurred in protein. During this period cell-associated radioactivity reached equilibrium and was totally recovered in the TCA-soluble fraction. After 5 min, the incorporation of 3H-leu into protein was linear for 2 h and was inhibited (98%) by the inclusion of 10 micrograms/ml cycloheximide. After 24 h of serum deprivation, insulin increased 3H-leu incorporation into protein by approximately 2-fold. The stimulation of protein synthesis by insulin was dose dependent (ED50 = 70 pM) and seen within 30 min. Proinsulin was approximately 10-fold less potent than insulin on a molar basis in stimulating neuronal protein synthesis. Insulin had no effect on the TCA-soluble fraction of 3H-leu at any time and did not influence the uptake of [3H]aminoisobutyric acid into neurons. The isotope ratio of 3H-leu/14C-leu in the leucyl tRNA pool was the same in control and insulin-treated neurons. Analysis of newly synthesized proteins by sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that insulin uniformly increased the incorporation of 14C-leu into all of the resolved neuronal proteins. We conclude from these data that (1) insulin rapidly stimulates overall protein synthesis in fetal neurons independent of amino acid uptake and aminoacyl tRNA precursor pools; (2) stimulation of protein synthesis is mediated by the brain subtype of insulin receptor; and (3) insulin is potentially an important in vivo growth factor for fetal central nervous system neurons

  7. GaN Bulk Growth and Epitaxy from Ca-Ga-N Solutions, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR proposal addresses the liquid phase epitaxy (LPE) of gallium nitride (GaN) films using nitrogen-enriched metal solutions. Growth of GaN from solutions...

  8. Fundamental aspects of nucleation and growth in the solution-phase synthesis of germanium nanocrystals

    KAUST Repository

    Codoluto, Stephen C.; Baumgardner, William J.; Hanrath, Tobias

    2010-01-01

    Colloidal Ge nanocrystals (NCs) were synthesized via the solution phase reduction of germanium(ii) iodide. We report a systematic investigation of the nanocrystal nucleation and growth as a function of synthesis conditions including the nature

  9. Bulk water phase and biofilm growth in drinking water at low nutrient conditions

    DEFF Research Database (Denmark)

    Boe-Hansen, Rasmus; Albrechtsen, Hans-Jørgen; Arvin, Erik

    2002-01-01

    , and cell-specific leucine incorporation rate. Bacteria in the bulk water phase incubated without the presence of biofilmexhibited a bacterial growth rate of 0.30 day1. The biofilmwas radioactively labelled by the addition of 14C-benzoic acid. Subsequently, a biofilmdetachm ent rate of 0.013 day1...... the formation of a mature quasi-stationary biofilm. At retention times of 12 h, total bacterial counts increased equivalent to a net bacterial growth rate of 0.048 day1. The bulk water phase bacteria exhibited a higher activity than the biofilmbacteria in terms of culturability, cell-specific ATP content......In this study, the bacterial growth dynamics of a drinking water distribution system at low nutrient conditions was studied in order to determine bacterial growth rates by a range of methods, and to compare growth rates in the bulk water phase and the biofilm. A model distribution system was used...

  10. Crystal growth, structure and phase studies on gold halides

    NARCIS (Netherlands)

    Janssen, Eugenius Maria Wilhelmus Janssen

    1977-01-01

    Only very corrosive substances attack gold, the most noble metal. In this study the reactivity and the phase diagrams of gold with the halogens chlorine, bromine and iodine have been investigated. owing to the noble behaviour of gold, its halides are sensitive to heat; on heating they decompose into

  11. Liquid phase epitaxial growth of heterostructured hierarchical MOF thin films

    KAUST Repository

    Chernikova, Valeriya; Shekhah, Osama; Spanopoulos, Ioannis; Trikalitis, Pantelis N.; Eddaoudi, Mohamed

    2017-01-01

    Precise control of epitaxial growth of MOF-on-MOF thin films, for ordered hierarchical tbo-type structures is demonstrated. The heterostructured MOF thin film was fabricated by successful sequential deposition of layers from two different MOFs. The 2-periodic layers, edge-transitive 4,4-square lattices regarded as supermolecular building layers, were commendably cross-linked using a combination of inorganic/organic and organic pillars.

  12. Liquid phase epitaxial growth of heterostructured hierarchical MOF thin films

    KAUST Repository

    Chernikova, Valeriya

    2017-05-10

    Precise control of epitaxial growth of MOF-on-MOF thin films, for ordered hierarchical tbo-type structures is demonstrated. The heterostructured MOF thin film was fabricated by successful sequential deposition of layers from two different MOFs. The 2-periodic layers, edge-transitive 4,4-square lattices regarded as supermolecular building layers, were commendably cross-linked using a combination of inorganic/organic and organic pillars.

  13. Effects of salt stress imposed during two growth phases on cauliflower production and quality.

    Science.gov (United States)

    Giuffrida, Francesco; Cassaniti, Carla; Malvuccio, Angelo; Leonardi, Cherubino

    2017-03-01

    Cultivation of cauliflower is diffused in Mediterranean areas where water salinity results in the need to identify alternative irrigation sources or management strategies. Using saline water during two growth phases (from transplanting to visible appearance of inflorescence or from appearance of inflorescence to head harvest), the present study aimed to identify the growth period that is more suitable for irrigation with low quality water in relation to cauliflower production and quality. Salinity affected cauliflower growth mainly when imposed in the first growth phase. The growth reduction depended mainly on ion-specific effects, although slight nutrient imbalances as a result of Na + and Cl - antagonisms were observed. The use of non-saline water in the first or second growth period reduced both the osmotic and toxic effects of salinity. When salinity was applied during inflorescence growth, yield was reduced because of a restriction of water accumulation in the head. The results of the present study demonstrate the possibility of producing marketable cauliflower heads under conditions of salinity by timing the application of the best quality water during the first growth phase to improve fruit quality and during the second phase to reduce the negative effects of salinity on yield. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  14. Phase competition in the growth of SrCoOx/LaAlO3 thin films

    Science.gov (United States)

    Zhang, Jie; Meng, Dechao; Huang, Haoliang; Cai, Honglei; Huang, Qiuping; Wang, Jianlin; Yang, Yuanjun; Zhai, Xiaofang; Fu, Zhengping; Lu, Yalin

    2018-02-01

    The reversible topotactic phase transformation between brownmillerite SrCoO2.5 to perovskite SrCoO3 has attracted more and more attention for potential applications as solid oxide fuels and electrolysis cells. However, the relatively easy transformation result from small thermal stable energy barriers between the two phases leads to unstable the structures. In the paper, amounts of SrCoO3-δ films have been prepared by pulsed laser deposition at optimized growth conditions with the temperature range of 590-720°C. The X-ray diffraction (XRD) results demonstrated that a phase competition emerged around 650°C. The Gibbs free energies of two phases at high temperature revealed the difference of stability of these two phases under different growth temperature. The optical spectroscopies and X-ray photoelectron spectroscopies were used to verify the electronic structure and chemical state differences between the two phases with distinct crystal structures.

  15. Catch-up growth following fetal growth restriction promotes rapid restoration of fat mass but without metabolic consequences at one year of age.

    Directory of Open Access Journals (Sweden)

    Jacques Beltrand

    Full Text Available BACKGROUND: Fetal growth restriction (FGR followed by rapid weight gain during early life has been suggested to be the initial sequence promoting central adiposity and insulin resistance. However, the link between fetal and early postnatal growth and the associated anthropometric and metabolic changes have been poorly studied. METHODOLOGY/PRINCIPAL FINDINGS: Over the first year of post-natal life, changes in body mass index, skinfold thickness and hormonal concentrations were prospectively monitored in 94 infants in whom the fetal growth velocity had previously been measured using a repeated standardized procedure of ultrasound fetal measurements. 45 infants, thinner at birth, had experienced previous FGR (FGR+ regardless of birth weight. Growth pattern in the first four months of life was characterized by greater change in BMI z-score in FGR+ (+1.26+/-1.2 vs +0.58 +/-1.17 SD in FGR- resulting in the restoration of BMI and of fat mass to values similar to FGR-, independently of caloric intakes. Growth velocity after 4 months was similar and BMI z-score and fat mass remained similar at 12 months of age. At both time-points, fetal growth velocity was an independent predictor of fat mass in FGR+. At one year, fasting insulin levels were not different but leptin was significantly higher in the FGR+ (4.43+/-1.41 vs 2.63+/-1 ng/ml in FGR-. CONCLUSION: Early catch-up growth is related to the fetal growth pattern itself, irrespective of birth weight, and is associated with higher insulin sensitivity and lower leptin levels after birth. Catch-up growth promotes the restoration of body size and fat stores without detrimental consequences at one year of age on body composition or metabolic profile. The higher leptin concentration at one year may reflect a positive energy balance in children who previously faced fetal growth restriction.

  16. Determination of crystal growth rates during rapid solidification of polycrystalline aluminum by nano-scale spatio-temporal resolution in situ transmission electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Zweiacker, K., E-mail: Kai@zweiacker.org; Liu, C.; Wiezorek, J. M. K. [Department of Mechanical Engineering and Materials Science, University of Pittsburgh, 648 Benedum Hall, 3700 OHara Street, Pittsburgh, Pennsylvania 15261 (United States); McKeown, J. T.; LaGrange, T.; Reed, B. W.; Campbell, G. H. [Materials Science Division, Physical and Life Science Directorate, Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94551 (United States)

    2016-08-07

    In situ investigations of rapid solidification in polycrystalline Al thin films were conducted using nano-scale spatio-temporal resolution dynamic transmission electron microscopy. Differences in crystal growth rates and asymmetries in melt pool development were observed as the heat extraction geometry was varied by controlling the proximity of the laser-pulse irradiation and the associated induced melt pools to the edge of the transmission electron microscopy support grid, which acts as a large heat sink. Experimental parameters have been established to maximize the reproducibility of the material response to the laser-pulse-related heating and to ensure that observations of the dynamical behavior of the metal are free from artifacts, leading to accurate interpretations and quantifiable measurements with improved precision. Interface migration rate measurements revealed solidification velocities that increased consistently from ∼1.3 m s{sup −1} to ∼2.5 m s{sup −1} during the rapid solidification process of the Al thin films. Under the influence of an additional large heat sink, increased crystal growth rates as high as 3.3 m s{sup −1} have been measured. The in situ experiments also provided evidence for development of a partially melted, two-phase region prior to the onset of rapid solidification facilitated crystal growth. Using the experimental observations and associated measurements as benchmarks, finite-element modeling based calculations of the melt pool evolution after pulsed laser irradiation have been performed to obtain estimates of the temperature evolution in the thin films.

  17. Multiphase flow and transport caused by spontaneous gas phase growth in the presence of dense non-aqueous phase liquid.

    Science.gov (United States)

    Roy, James W; Smith, James E

    2007-01-30

    Disconnected bubbles or ganglia of trapped gas may occur below the top of the capillary fringe through a number of mechanisms. In the presence of dense non-aqueous phase liquid (DNAPL), the disconnected gas phase experiences mass transfer of dissolved gases, including volatile components from the DNAPL. The properties of the gas phase interface can also change. This work shows for the first time that when seed gas bubbles exist spontaneous gas phase growth can be expected to occur and can significantly affect water-gas-DNAPL distributions, fluid flow, and mass transfer. Source zone behaviour was observed in three different experiments performed in a 2-dimensional flow cell. In each case, a DNAPL pool was created in a zone of larger glass beads over smaller glass beads, which served as a capillary barrier. In one experiment effluent water samples were analyzed to determine the vertical concentration profile of the plume above the pool. The experiments effectively demonstrated a) a cycle of spontaneous gas phase expansion and vertical advective mobilization of gas bubbles and ganglia above the DNAPL source zone, b) DNAPL redistribution caused by gas phase growth and mobilization, and c) that these processes can significantly affect mass transport from a NAPL source zone.

  18. Phase diagram of nanoscale alloy particles used for vapor-liquid-solid growth of semiconductor nanowires.

    Science.gov (United States)

    Sutter, Eli; Sutter, Peter

    2008-02-01

    We use transmission electron microscopy observations to establish the parts of the phase diagram of nanometer sized Au-Ge alloy drops at the tips of Ge nanowires (NWs) that determine their temperature-dependent equilibrium composition and, hence, their exchange of semiconductor material with the NWs. We find that the phase diagram of the nanoscale drop deviates significantly from that of the bulk alloy, which explains discrepancies between actual growth results and predictions on the basis of the bulk-phase equilibria. Our findings provide the basis for tailoring vapor-liquid-solid growth to achieve complex one-dimensional materials geometries.

  19. Research on water hammer forces caused by rapid growth of bubbles at severe accidents of water cooled reactors

    International Nuclear Information System (INIS)

    Inasaka, Fujio; Adachi, Masaki; Aya, Izuo

    2004-01-01

    At severe accidents of Water Cooled Reactors a great deal of gas is expected to be produced in a short time within the water of lower part of nuclear pressure vessel and containment vessel caused by hydrogen production with a metal water reaction and steam explosions with direct contact of melting core and water. Water hammer forces caused by rapid growth of bubbles shall work on the wall of containment vessel and affect its integrity. Coherency of water block movement is not clear, whether simultaneous or in the same direction. Water block behavior and water hammer forces caused by rapid growth of bubbles have been tested using a modified scale model and analyzed to obtain experimental correlated equation to estimate water block's rising distance and velocity from water hammer data. Numerical analysis using RELAP5-3D (Reactor Excursion and Leak Analysis Program) has been conducted to evaluate water hammer forces and makes clear its modifications needed. (T. Tanaka)

  20. Change in Photosystem II Photochemistry During Algal Growth Phases of Chlorella vulgaris and Scenedesmus obliquus.

    Science.gov (United States)

    Oukarroum, Abdallah

    2016-06-01

    Sensitivity of photosynthetic processes towards environmental stress is used as a bioanalytical tool to evaluate the responses of aquatic plants to a changing environment. In this paper, change of biomass density, chlorophyll a fluorescence and photosynthetic parameters during growth phases of two microalgae Chlorella vulgaris and Scenedesmus obliquus were studied. The photosynthetic growth behaviour changed significantly with cell age and algae species. During the exponential phase of growth, the photosynthesis capacity reached its maximum and decreased in ageing algal culture during stationary phase. In conclusion, the chlorophyll a fluorescence OJIP method and the derived fluorescence parameters would be an accurate method for obtaining information on maximum photosynthetic capacities and monitoring algal cell growth. This will contribute to more understanding, for example, of toxic actions of pollutants in microalgae test.

  1. Embracing the River: Smart Growth Strategies for Assisting in Cedar Rapids' Recovery

    Science.gov (United States)

    This report from an EPA-FEMA technical assistance project with Cedar Rapids, IA, offers ideas to encourage infill development, make development more resilient to floods, and improve stormwater management.

  2. Phase evolution and infrared transmittance in monophasic VO{sub 2} synthesized by a rapid non-equilibrium process

    Energy Technology Data Exchange (ETDEWEB)

    Rajeswaran, Bharathi, E-mail: rajeswaran.bharathi@gmail.com; Umarji, A.M.

    2017-04-01

    VO{sub 2} displays a semiconducting to metallic (SMT) transition accessible near room temperature. This makes it one of the most sought after materials for electrical and optical switching. But this can be utilized only when the synthesis process yields phase pure VO{sub 2} without other oxides of vanadium. Across the SMT, VO{sub 2} exhibits difference crystal structures with a rich phase behavior of insulating monoclinic M1, M2 and T phases. The objective of this study is to synthesize phase pure VO{sub 2} and to investigate its structural evolution and infrared switching during the transition. In this work, a rapid non-equilibrium process namely Solution Combustion Synthesis (SCS) was employed. The structural phase transition (SPT) of VO{sub 2} nanostructures synthesized by SCS was investigated by in-situ temperature controlled XRD across the SMT. Gaussian curve fittings for measured XRD patterns revealed that competing phases of M1 and R significantly contribute to the observed pattern at every increase in temperature. The powders were further characterized by FTIR, DSC and DC electrical conductivity. These studies show that a sharp SMT was observed at 68–70 °C. Infrared transmittance experiments pinpointed the transition. Carrier density and mobility of VO{sub 2} were calculated. This suggests that this VO{sub 2} thus synthesized displays excellent phase transition behavior and can be utilized in optical and electrical switching. - Highlights: • VO{sub 2} has been synthesized by an easy, rapid, cost-effective, two-step, novel reaction. • High temperature XRD and DSC showed first order phase transition. • IR transmittance showed a decrease in transmittance at high temperatures enabling it to be used for IR sensing.

  3. Safety dose of three commercially used growth promoters: nuricell- aqua, hepaprotect-aqua and rapid-grow on growth and survival of Thai pangas (Pangasianodon hypophthalmus

    Directory of Open Access Journals (Sweden)

    Md. Ariful Islam

    2014-02-01

    Full Text Available Objective: To optimize the dose of 3 commonly used growth promoters, viz., Nuricell-Aqua (composition: glucomannan complex and mannose polymer, Hepaprotect-Aqua (composition: β-glucan, mannose polymer and essential oil and Rapid-Grow (composition: organic acid and their salt, β-glucan, mannose oligosaccharide and essential oil, using Thai pangas (Pangasiandon hypophthalmus as cultured species. Methods: Thai pangas fingerlings with an average length and weight of 11 cm and 10 g were reared under laboratory condition and growth promoters were fed after incorporating them with a test diet at a ratio of 10% of their body weight for a period of 28 d. Estimation of data on growth such as weight gain (g, specific growth rate, survivability (% test in each aquarium were conducted and data were analyzed using statistical software. Results: After 28 d of feeding with Nutricell-Aqua, 10 mg/(20 g feed·day, which was the dose recommended by the manufacturer, was found better. When Hepaprotect-Aqua and Rapid-Grow were employed, performance was found to be better with the dose of 60 mg/(20 g feed·day which was 1.5 times higher than the dose recommended by the corresponding manufacturer. Conclusions: These results suggest that chemicals and feed additives marketed in Bangladesh Fish Feed Market need further testing under Bangladesh climatic condition before being marketed.

  4. Hybrid vapor phase-solution phase growth techniques for improved CZT(S,Se) photovoltaic device performance

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Liang-Yi; Gershon, Talia S.; Haight, Richard A.; Lee, Yun Seog

    2016-12-27

    A hybrid vapor phase-solution phase CZT(S,Se) growth technique is provided. In one aspect, a method of forming a kesterite absorber material on a substrate includes the steps of: depositing a layer of a first kesterite material on the substrate using a vapor phase deposition process, wherein the first kesterite material includes Cu, Zn, Sn, and at least one of S and Se; annealing the first kesterite material to crystallize the first kesterite material; and depositing a layer of a second kesterite material on a side of the first kesterite material opposite the substrate using a solution phase deposition process, wherein the second kesterite material includes Cu, Zn, Sn, and at least one of S and Se, wherein the first kesterite material and the second kesterite material form a multi-layer stack of the absorber material on the substrate. A photovoltaic device and method of formation thereof are also provided.

  5. Influence of temperature on growth rate and lag phase of fungi isolated from Argentine corn.

    Science.gov (United States)

    González, H H; Resnik, S L; Vaamonde, G

    1988-03-01

    The influence of temperature on the growth of nine strains of fungi belonging to the genera Eurotium, Aspergillus, Penicillium and Fusarium has been investigated for the temperature range 15-35 degrees C. The lag phase and the growth rate were evaluated by using a laboratory medium. The maximum growth rate for E. repens, A. wentii and P. chrysogenum was observed at about 25 degrees C, for P. citrinum near 30 degrees C and for F. semitectum and F. moniliforme between 20 and 25 degrees C. The growth rate of A. niger, A. flavus and A. parasiticus increased with increasing temperatures in the range studied. For all strains studied it appeared that the higher the growth rate the lower the lag phase was.

  6. Rapid Construction of Fe-Co-Ni Composition-Phase Map by Combinatorial Materials Chip Approach.

    Science.gov (United States)

    Xing, Hui; Zhao, Bingbing; Wang, Yujie; Zhang, Xiaoyi; Ren, Yang; Yan, Ningning; Gao, Tieren; Li, Jindong; Zhang, Lanting; Wang, Hong

    2018-03-12

    One hundred nanometer thick Fe-Co-Ni material chips were prepared and isothermally annealed at 500, 600, and 700 °C, respectively. Pixel-by-pixel composition and structural mapping was performed by microbeam X-ray at synchrotron light source. Diffraction images were recorded at a rate of 1 pattern/s. The XRD patterns were automatically processed, phase-identified, and categorized by hierarchical clustering algorithm to construct the composition-phase map. The resulting maps are consistent with corresponding isothermal sections reported in the ASM Alloy Phase Diagram Database, verifying the effectiveness of the present approach in phase diagram construction.

  7. Effect of vapor-phase oxygen on chemical vapor deposition growth of graphene

    Science.gov (United States)

    Terasawa, Tomo-o.; Saiki, Koichiro

    2015-03-01

    To obtain a large-area single-crystal graphene, chemical vapor deposition (CVD) growth on Cu is considered the most promising. Recently, the surface oxygen on Cu has been found to suppress the nucleation of graphene. However, the effect of oxygen in the vapor phase was not elucidated sufficiently. Here, we investigate the effect of O2 partial pressure (PO2) on the CVD growth of graphene using radiation-mode optical microscopy. The nucleation density of graphene decreases monotonically with PO2, while its growth rate reaches a maximum at a certain pressure. Our results indicate that PO2 is an important parameter to optimize in the CVD growth of graphene.

  8. The speed of growth of the gamma phase comes prime in nickel based alloys

    International Nuclear Information System (INIS)

    Peretti, M.M; Ges, A.M; Versaci, R.A

    2004-01-01

    Nickel-based alloys have a high fraction in volume of precipitate phase. This precipitate phase provides the characteristics of high mechanical resistance to high temperatures and, therefore, a study of the growth of this phase can predict the behavior of the components in service. This work studies the speed of growth in the alloy INCONEL 713C at temperatures of 800 o C, 875 o C and 950 o C with different treatment times. The present phase in this alloy is Ni3(AlTi), with a very high fraction in volume. The follow-up on the growth of the phase was carried out using scanning and transmission electron microscopy techniques. The speed of growth presents modifications that increase and decrease as a function of time. These variations in speed are attributed to modifications in the size and morphology of the precipitate particles. The changes in size and morphology directly influence the interfacial energy that produces the change in the speed of growth (CW)

  9. Rapid Growth of Large Single-Crystalline Graphene via Second Passivation and Multistage Carbon Supply.

    Science.gov (United States)

    Lin, Li; Sun, Luzhao; Zhang, Jincan; Sun, Jingyu; Koh, Ai Leen; Peng, Hailin; Liu, Zhongfan

    2016-06-01

    A second passivation and a multistage carbon-source supply (CSS) allow a 50-fold enhancement of the growth rate of large single-crystalline graphene with a record growth rate of 101 μm min(-1) , almost 10 times higher than for pure copper. To this end the CSS is tailored at separate stages of graphene growth on copper foil, combined with an effective suppression of new spontaneous nucleation via second passivation. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Bacterial Growth Phase Influences Methylmercury Production by the Sulfate-Reducing Bacterium Desulfovibrio desulfuricans ND132

    Energy Technology Data Exchange (ETDEWEB)

    Biswas, Abir [ORNL; Brooks, Scott C [ORNL; Miller, Carrie L [ORNL; Mosher, Jennifer J [ORNL; Yin, Xiangping Lisa [ORNL; Drake, Meghan M [ORNL

    2011-01-01

    The effect of bacterial growth phase is an aspect of mercury (Hg) methylation that previous studies have not investigated in detail. Here we consider the effect of growth phase (mid-log, late-log and late stationary phase) on Hg methylation by the known methylator Desulfovibrio desulfuricans ND132. We tested the addition of Hg alone (chloride-complex), Hg with Suwannee River natural organic matter (SRNOM) (unequilibrated), and Hg equilibrated with SRNOM on monomethylmercury (MMHg) production by ND132 over a growth curve in pyruvate-fumarate media. This NOM did not affect MMHg production even under very low Hg:SRNOM ratios, where Hg binding is predicted to be dominated by high energy sites. Adding Hg or Hg-NOM to growing cultures 24h before sampling (late addition) resulted in {approx}2x greater net fraction of Hg methylated than for comparably aged cultures exposed to Hg from the initial culture inoculation (early addition). Mid- and late-log phase cultures produced similar amounts of MMHg, but late stationary phase cultures (both under early and late Hg addition conditions) produced up to {approx}3x more MMHg, indicating the potential importance of growth phase in studies of MMHg production.

  11. Bacterial Growth Phase Influences Methylmercury Production by the Sulfate-Reducing Bacterium Desulfovibrio desulfuricans ND132

    Energy Technology Data Exchange (ETDEWEB)

    Biswas, Abir [ORNL; Brooks, Scott C [ORNL; Miller, Carrie L [ORNL; Mosher, Jennifer J [ORNL; Yin, Xiangping Lisa [ORNL; Drake, Meghan M [ORNL

    2011-01-01

    The effect of bacterial growth phase is an aspect of mercury (Hg) methylation that previous studies have not investigated in detail. Here we consider the effect of growth phase (mid-log, late-log and late stationary phase) on Hg methylation by the known methylator Desulfovibrio desulfuricans ND132. We tested the addition of Hg alone (chloride-complex), Hg with Suwannee River natural organic matter (SRNOM) (unequilibrated), and Hg equilibrated with SRNOM on monomethylmercury (MMHg) production by ND132 over a growth curve in pyruvate fumarate media. This NOM did not affect MMHg production even under very low Hg: SRNOM ratios, where Hg binding is predicted to be dominated by high energy sites. Adding Hg or Hg NOM to growing cultures 24 h before sampling (late addition) resulted in ~2 greater net fraction of Hg methylated than for comparably aged cultures exposed to Hg from the initial culture inoculation (early addition). Mid-and late-log phase cultures produced similar amounts of MMHg, but late stationary phase cultures (both under early and late Hg addition conditions) produced up to ~3 more MMHg, indicating the potential importance of growth phase in studies of MMHg production.

  12. Effect of algal growth phase on Aureococcus anophagefferens susceptibility to hydrogen peroxide

    International Nuclear Information System (INIS)

    Randhawa, Varunpreet; Thakkar, Megha; Wei, Liping

    2013-01-01

    Highlights: •Brown tide alga's susceptibility to H 2 O 2 was examined via growth and physiology responses. •The study was designed equalizing the influence of the media and cell density in test cultures. •Stationary cells was more sensitive to H 2 O 2 than exponential cells. •Stationary cells showed weaker non-protein thiol up-regulation than exponential cells. •Stationary cells mediated greater H 2 O 2 decomposition than exponential cells did. -- Abstract: A cell's growth phase could affect its susceptibility to a biocide in microbial control. This study examines the growth phase dependent susceptibility of a brown tide bloom alga Aureococcus anophagefferens to microbial biocide hydrogen peroxide (H 2 O 2 ). Test cultures of A. anophagefferens cells in exponential and stationary growth phase and similar initial cell density (1.6 × 10 6 cells mL −1 ) were exposed to 0.4–1.6 mg L −1 H 2 O 2 . Changes in algal growth (in vivo fluorescence, total chlorophyll a, and cell density), cell physiology (maximum quantum yield of photosystem II, and total intracellular non-protein thiols), and H 2 O 2 decomposition were quantified. Results show that the stationary phase cells are more susceptible to H 2 O 2 than the exponential phase cells, and this is attributed to the weaker ROS (reactive oxygen species) scavenging system and consequently greater cell damage in stationary phase cells. The stationary phase cells potentially require 30–40% less H 2 O 2 to reach 90% removal within 12 h of treatment as compared to the exponential phase cells. The results have practical implications in brown tide bloom control with respect to the timing and the dosage of H 2 O 2 application

  13. Socioeconomic Status Accounts for Rapidly Increasing Geographic Variation in the Incidence of Poor Fetal Growth

    Science.gov (United States)

    Ball, Stephen J.; Jacoby, Peter; Zubrick, Stephen R.

    2013-01-01

    Fetal growth is an important risk factor for infant morbidity and mortality. In turn, socioeconomic status is a key predictor of fetal growth; however, other sociodemographic factors and environmental effects may also be important. This study modelled geographic variation in poor fetal growth after accounting for socioeconomic status, with a fixed effect for socioeconomic status and a combination of spatially-correlated and spatially-uncorrelated random effects. The dataset comprised 88,246 liveborn singletons, aggregated within suburbs in Perth, Western Australia. Low socioeconomic status was strongly associated with an increased risk of poor fetal growth. An increase in geographic variation of poor fetal growth from 1999–2001 (interquartile odds ratio among suburbs = 1.20) to 2004–2006 (interquartile odds ratio = 1.40) indicated a widening risk disparity by socioeconomic status. Low levels of residual spatial patterns strengthen the case for targeting policies and practices in areas of low socioeconomic status for improved outcomes. This study indicates an alarming increase in geographic inequalities in poor fetal growth in Perth which warrants further research into the specific aspects of socioeconomic status that act as risk factors. PMID:23799513

  14. Room-temperature saturated ferroelectric polarization in BiFeO3 ceramics synthesized by rapid liquid phase sintering

    International Nuclear Information System (INIS)

    Wang, Y.P.; Zhou, L.; Zhang, M.F.; Chen, X.Y.; Liu, J.-M.; Liu, Z.G.

    2004-01-01

    Single-phased ferroelectromagnet BiFeO 3 ceramics with high resistivity were synthesized by a rapid liquid phase sintering technique. Saturated ferroelectric hysteresis loops were observed at room temperature in the ceramics sintered at 880 deg. C for 450 s. The spontaneous polarization, remnant polarization, and the coercive field are 8.9 μC/cm 2 , 4.0 μC/cm 2 , and 39 kV/cm, respectively, under an applied field of 100 kV/cm. It is proposed that the formation of Fe 2+ and an oxygen deficiency leading to the higher leakage can be greatly suppressed by the very high heating rate, short sintering period, and liquid phase sintering technique. The latter was also found effective in increasing the density of the ceramics. The sintering technique developed in this work is expected to be useful in synthesizing other ceramics from multivalent or volatile starting materials

  15. Rapid Growth of Psychology Programs in Turkey: Undergraduate Curriculum and Structural Challenges

    Science.gov (United States)

    Sümer, Nebi

    2016-01-01

    Similar to the other developing countries, undergraduate psychology programs in Turkish universities have rapidly grown in the last two decades. Although this sharp increment signifies the need for psychologists, it has also caused a number of challenges for effective teaching of psychology. The department chairs (N = 42) were interviewed with an…

  16. Growth order and activation energies for grain growth of Ti-6Al-4V alloy in β phase

    International Nuclear Information System (INIS)

    Gil, F.J.; Planell, J.A.

    1991-01-01

    This paper reports that one of the reasons usually stated for avoiding annealing treatments and hot working of Ti-6Al-4V alloy at temperatures over the β transus is the large grain growth which takes place at such temperatures. The aim of the present work is to quantify the grain growth kinetics when the alloy is heat treated in its β phase. It is well known that the driving force for grain growth comes from the surface energy of the grain boundaries. When thermal energy is given to the material, diffusion takes place which leads to grain selection. This means that the number of grains decreases, their size increases, the area of the grain boundaries decreases with the total energy stored in them and consequently a state of higher thermodynamic stability is reached

  17. Rapid replacement of bridge deck expansion joints study - phase I : [tech transfer summary].

    Science.gov (United States)

    2014-12-01

    This initial research phase focused on documenting the current : means and methods of bridge expansion joint deterioration, : maintenance, and replacement and on identifying improvements : through all of the input gathered.

  18. Linearized FUN3D for Rapid Aeroelastic and Aeroservoelastic Design and Analysis, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — In Phase I, a prototypical FUN3D-based ZONA Euler Unsteady Solver (FunZEUS) was developed to generate the Generalized Aerodynamic Forces (GAFs) due to structural...

  19. Rapid and widely disseminated acute phase protein response after experimental bacterial infection of pigs

    DEFF Research Database (Denmark)

    Skovgaard, Kerstin; Mortensen, Shila; Boye, Mette

    2009-01-01

    The acute phase protein response is a well-described generalized early host response to tissue injury, inflammation and infection, observed as pronounced changes in the concentrations of a number of circulating serum proteins. The biological function of this response and its interplay with other...... parts of innate host defence reactions remain somewhat elusive. In order to gain new insight into this early host defence response in the context of bacterial infection we studied gene expression changes in peripheral lymphoid tissues as compared to hepatic expression changes, 14-18 h after lung...... with measurements of interleukin-6 and selected acute phase proteins in serum. C-reactive protein and serum amyloid A were clearly induced 14-18 h after infection. Extrahepatic expression of acute phase proteins was found to be dramatically altered as a result of the lung infection with an extrahepatic acute phase...

  20. Recovering from a bad start: rapid adaptation and tradeoffs to growth below a threshold density

    Directory of Open Access Journals (Sweden)

    Marx Christopher J

    2012-07-01

    Full Text Available Abstract Background Bacterial growth in well-mixed culture is often assumed to be an autonomous process only depending upon the external conditions under control of the investigator. However, increasingly there is awareness that interactions between cells in culture can lead to surprising phenomena such as density-dependence in the initiation of growth. Results Here I report the unexpected discovery of a density threshold for growth of a strain of Methylobacterium extorquens AM1 used to inoculate eight replicate populations that were evolved in methanol. Six of these populations failed to grow to the expected full density during the first couple transfers. Remarkably, the final cell number of six populations crashed to levels 60- to 400-fold smaller than their cohorts. Five of these populations recovered to full density soon after, but one population remained an order of magnitude smaller for over one hundred generations. These variable dynamics appeared to be due to a density threshold for growth that was specific to both this particular ancestral strain and to growth on methanol. When tested at full density, this population had become less fit than its ancestor. Simply increasing the initial dilution 16-fold reversed this result, revealing that this population had more than a 3-fold advantage when tested at this lower density. As this population evolved and ultimately recovered to the same final density range as the other populations this low-density advantage waned. Conclusions These results demonstrate surprisingly strong tradeoffs during adaptation to growth at low absolute densities that manifest over just a 16-fold change in density. Capturing laboratory examples of transitions to and from growth at low density may help us understand the physiological and evolutionary forces that have led to the unusual properties of natural bacteria that have specialized to low-density environments such as the open ocean.

  1. Recovering from a bad start: rapid adaptation and tradeoffs to growth below a threshold density.

    Science.gov (United States)

    Marx, Christopher J

    2012-07-04

    Bacterial growth in well-mixed culture is often assumed to be an autonomous process only depending upon the external conditions under control of the investigator. However, increasingly there is awareness that interactions between cells in culture can lead to surprising phenomena such as density-dependence in the initiation of growth. Here I report the unexpected discovery of a density threshold for growth of a strain of Methylobacterium extorquens AM1 used to inoculate eight replicate populations that were evolved in methanol. Six of these populations failed to grow to the expected full density during the first couple transfers. Remarkably, the final cell number of six populations crashed to levels 60- to 400-fold smaller than their cohorts. Five of these populations recovered to full density soon after, but one population remained an order of magnitude smaller for over one hundred generations. These variable dynamics appeared to be due to a density threshold for growth that was specific to both this particular ancestral strain and to growth on methanol. When tested at full density, this population had become less fit than its ancestor. Simply increasing the initial dilution 16-fold reversed this result, revealing that this population had more than a 3-fold advantage when tested at this lower density. As this population evolved and ultimately recovered to the same final density range as the other populations this low-density advantage waned. These results demonstrate surprisingly strong tradeoffs during adaptation to growth at low absolute densities that manifest over just a 16-fold change in density. Capturing laboratory examples of transitions to and from growth at low density may help us understand the physiological and evolutionary forces that have led to the unusual properties of natural bacteria that have specialized to low-density environments such as the open ocean.

  2. Continuation of growth hormone therapy versus placebo in transition-phase patients with growth hormone deficiency

    DEFF Research Database (Denmark)

    Jørgensen, Jens; Nørrelund, Helene; Vahl, Nina

    2002-01-01

    In a placebo-controlled, parallel study of 18 patients with a mean age of 20 years who had confirmed growth hormone (GH) deficiency, we evaluated body composition, insulin sensitivity, and glucose turnover at baseline (when all were receiving GH replacement); after 12 months of continued GH therapy...

  3. Assessment of phase constitution on the Al-rich region of rapidly solidified Al-Co-Fe-Cr alloys

    Energy Technology Data Exchange (ETDEWEB)

    Wolf, W., E-mail: witorw@gmail.com [Programa de Pós-Graduação em Ciência e Engenharia de Materiais, Universidade Federal de São Carlos, Rod. Washington Luiz, Km 235, 13565-905 São Carlos, SP (Brazil); Bolfarini, C., E-mail: cbolfa@ufscar.br [Departamento de Engenharia de Materiais, Universidade Federal de São Carlos, Rod. Washington Luiz, Km 235, 13565-905 São Carlos, SP (Brazil); Kiminami, C.S., E-mail: kiminami@ufscar.br [Departamento de Engenharia de Materiais, Universidade Federal de São Carlos, Rod. Washington Luiz, Km 235, 13565-905 São Carlos, SP (Brazil); Botta, W.J., E-mail: wjbotta@ufscar.br [Departamento de Engenharia de Materiais, Universidade Federal de São Carlos, Rod. Washington Luiz, Km 235, 13565-905 São Carlos, SP (Brazil)

    2016-12-15

    The formation of quasicrystalline approximants in rapidly solidified Al-Co-Fe-Cr alloys was investigated. Alloys of atomic composition Al{sub 71}Co{sub 13}Fe{sub 8}Cr{sub 8}, Al{sub 77}Co{sub 11}Fe{sub 6}Cr{sub 6} and Al{sub 76}Co{sub 19}Fe{sub 4}Cr{sub 1} were produced using melt spinning and arc melting methods and their microstructural characterization was carried out by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. Up to the present there is no consensus in the literature regarding the formation of quasicrystalline phase or quasicrystalline approximants in the Al{sub 71}Co{sub 13}Fe{sub 8}Cr{sub 8} alloy. This work presents, for the first time, a detailed structural characterization of selected alloys in the Al-Co-Fe-Cr system close to the atomic composition Al{sub 71}Co{sub 13}Fe{sub 8}Cr{sub 8}. The results indicated the samples to be composed, mostly, by two intermetallic phases, which are quaternary extensions of Al{sub 5}Co{sub 2} and Al{sub 13}Co{sub 4} and are quasicrystalline approximants. Although the Al{sub 5}Co{sub 2} phase has already been reported in the Al{sub 71}Co{sub 13}Fe{sub 8}Cr{sub 8} alloy, the presence of the monoclinic Al{sub 13}Co{sub 4} is now identified for the first time in the as cast state. In the binary Al-Co system a quasicrystalline phase is known to form in a rapidly solidified alloy with composition close to the monoclinic and orthorhombic Al{sub 13}Co{sub 4} phases. This binary quasicrystalline phase presents an average valence electron per atom (e/a) between 1.7 and 1.9; thus, in addition to the Al{sub 71}Co{sub 13}Fe{sub 8}Cr{sub 8} alloy, the compositions Al{sub 77}Co{sub 11}Fe{sub 6}Cr{sub 6} and Al{sub 76}Co{sub 19}Fe{sub 4}Cr{sub 1} were chosen to be within the region of formation of the quaternary extension of the Al{sub 13}Co{sub 4} phase and also within the (e/a) of 1.7 to 1.9. However, no quasicrystalline phase is present in any of the studied alloys. The Al-Co-Fe-Cr system

  4. Assessment of phase constitution on the Al-rich region of rapidly solidified Al-Co-Fe-Cr alloys

    International Nuclear Information System (INIS)

    Wolf, W.; Bolfarini, C.; Kiminami, C.S.; Botta, W.J.

    2016-01-01

    The formation of quasicrystalline approximants in rapidly solidified Al-Co-Fe-Cr alloys was investigated. Alloys of atomic composition Al 71 Co 13 Fe 8 Cr 8 , Al 77 Co 11 Fe 6 Cr 6 and Al 76 Co 19 Fe 4 Cr 1 were produced using melt spinning and arc melting methods and their microstructural characterization was carried out by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. Up to the present there is no consensus in the literature regarding the formation of quasicrystalline phase or quasicrystalline approximants in the Al 71 Co 13 Fe 8 Cr 8 alloy. This work presents, for the first time, a detailed structural characterization of selected alloys in the Al-Co-Fe-Cr system close to the atomic composition Al 71 Co 13 Fe 8 Cr 8 . The results indicated the samples to be composed, mostly, by two intermetallic phases, which are quaternary extensions of Al 5 Co 2 and Al 13 Co 4 and are quasicrystalline approximants. Although the Al 5 Co 2 phase has already been reported in the Al 71 Co 13 Fe 8 Cr 8 alloy, the presence of the monoclinic Al 13 Co 4 is now identified for the first time in the as cast state. In the binary Al-Co system a quasicrystalline phase is known to form in a rapidly solidified alloy with composition close to the monoclinic and orthorhombic Al 13 Co 4 phases. This binary quasicrystalline phase presents an average valence electron per atom (e/a) between 1.7 and 1.9; thus, in addition to the Al 71 Co 13 Fe 8 Cr 8 alloy, the compositions Al 77 Co 11 Fe 6 Cr 6 and Al 76 Co 19 Fe 4 Cr 1 were chosen to be within the region of formation of the quaternary extension of the Al 13 Co 4 phase and also within the (e/a) of 1.7 to 1.9. However, no quasicrystalline phase is present in any of the studied alloys. The Al-Co-Fe-Cr system, around the compositions studied, is composed of quaternary extensions of Al-Co intermetallic phases, which present solubility of Fe and Cr at Co atomic sites. - Highlights: •The Al rich region of the Al

  5. Challenges of rapid economic growth in China: Reconciling sustainable energy use, environmental stewardship and social development

    International Nuclear Information System (INIS)

    Li Yong; Oberheitmann, Andreas

    2009-01-01

    China aims at quadrupling per-capita GDP by 2020 compared to the year 2000. Without any energy and environmental policy measures, this tremendous economic growth would be associated with a quadrupling of primary energy consumption up to 6.3 billion tons of standard coal equivalents (sce) and energy-related CO 2 -emissions of 13.9 billion tons Against this background, this paper is to set China's need to implement its sustainable development strategy into the quantitative context of the countries economic development and subsequent economic growth-related environmental problems. China is urgently searching for a way to ease the negative implications of economic growth and has committed itself to achieve a level of 3.0 billion ton sce primary energy consumption in 2020. As a consequence, the macro-economic energy intensity has to be reduced by 53% by 2020. A reduction of 53% by 2020 would lead to an energy intensity level 30% points below the year-2000 level of developed countries. As for natural resources, the expected economic growth will lead to an increase of crude oil net-imports up to 455 million ton sce in 2020 and 650 million ton sce in 2030. As for regional income distribution, economic growth helped to decrease existing inequities

  6. The Rapid Urban Growth Triad: A New Conceptual Framework for Examining the Urban Transition in Developing Countries

    Directory of Open Access Journals (Sweden)

    Kyle Farrell

    2017-08-01

    Full Text Available Although the urban transition is a universal event that unfolds in all countries, the determinants, patterns, and outcomes do not necessarily follow a uniform process. With the urban transition being basically completed in developed countries around the turn of the 21st century, the growth of cities today is almost entirely confined to developing countries. Still, much of our conceptual understanding of this process is derived from earlier accounts, with definitions rooted in a historical context. This has resulted in common misconceptions such as a tendency to view the growth of cities primarily as an outcome of rural to urban migration, neglecting the growing contributions of urban natural population increase and reclassification of rural areas. A tendency to treat the components of urban growth in isolation has created a rift within the urban studies discourse, preventing any real theorization of their combined impacts and the interplay among them. Applying a systems thinking approach, this paper introduces a multidisciplinary framework for conceptualizing rapid urban growth in developing countries. The framework offers explanatory power to previously neglected components of urban growth and serves as a diagnostic for examining the urban transition—ultimately revealing new policy levers for managing it in a sustainable way.

  7. Phase and structural transformations in annealed copper coatings in relation to oxide whisker growth

    Energy Technology Data Exchange (ETDEWEB)

    Dorogov, M.V.; Priezzheva, A.N. [Togliatti State University, Belorusskaya 14, 445667 Togliatti (Russian Federation); Vlassov, S., E-mail: vlassovs@ut.ee [Institute of Solid State Physics, University of Latvia, Kengaraga 8, LV-1063 Riga (Latvia); Kink, I.; Shulga, E. [Institute of Physics, University of Tartu, Ravila 14c, 50411 Tartu (Estonia); Dorogin, L.M. [Togliatti State University, Belorusskaya 14, 445667 Togliatti (Russian Federation); Institute of Physics, University of Tartu, Ravila 14c, 50411 Tartu (Estonia); ITMO University, Kronverkskiy 49, 197101 Saint Petersburg (Russian Federation); Lõhmus, R. [Institute of Physics, University of Tartu, Ravila 14c, 50411 Tartu (Estonia); Tyurkov, M.N.; Vikarchuk, A.A. [Togliatti State University, Belorusskaya 14, 445667 Togliatti (Russian Federation); Romanov, A.E. [Togliatti State University, Belorusskaya 14, 445667 Togliatti (Russian Federation); Institute of Physics, University of Tartu, Ravila 14c, 50411 Tartu (Estonia); ITMO University, Kronverkskiy 49, 197101 Saint Petersburg (Russian Federation); Ioffe Physical Technical Institute, RAS, Polytechnicheskaya 26, 194021 Saint Petersburg (Russian Federation)

    2015-08-15

    Highlights: • Coatings prepared by Cu microparticle electrodeposition. • Structural and phase transformation in Cu coatings annealed at 400 °C. • Annealing is accompanied by intensive growth of CuO whiskers. • Layered oxide phases (Cu{sub 2}O and CuO) in the coating are characterized. • Formation of volumetric defects in the coating is demonstrated. - Abstract: We describe structural and phase transformation in copper coatings made of microparticles during heating and annealing in air in the temperature range up to 400 °C. Such thermal treatment is accompanied by intensive CuO nanowhisker growth on the coating surface and the formation of the layered oxide phases (Cu{sub 2}O and CuO) in the coating interior. X-ray diffraction and focused ion beam (FIB) are employed to characterize the multilayer structure of annealed copper coatings. Formation of volumetric defects such as voids and cracks in the coating is demonstrated.

  8. Coral reef growth in an era of rapidly rising sea level: predictions and suggestions for long-term research

    Energy Technology Data Exchange (ETDEWEB)

    Buddemeier, R W; Smith, S V

    1988-01-01

    Coral reef growth is intimately linked to sea level. It has been postulated that over the next century, sea level will rise at a probable average rate of 15 mm/year, in response to fossil fuel emissions, heating, and melting of the Antarctic ice cap. This predicted rate of sea level rise is five times the present modal rate of vertical accretion on coral reef flats and 50% greater than the maximum vertical accretion rates apparently attained by coral reefs. We use these predictions and observations to offer the following hypothesis for reef growth over the next century. The vertical accretion rates of protected reef flats will accelerate from the present modal rate up to the maximum rate, in response to the more rapidly rising sea level. This more rapid vertical accretion rate will be insufficient to keep up with sea level rise, if present predictions prove to be correct. Less protected reef flats will slow their rate of growth as they become inundated and subjected to erosion by progressively larger waves. This projected sea level rise and postulated reef response will provide an opportunity for long- term studies of the response of coral reef systems to a predictable and measurable forcing function.

  9. Rapid purification of radiodinated glucagon with Sep-PakR reversed phase cartridges

    International Nuclear Information System (INIS)

    Borghi, V.C.; Nascimento, M.; Wajchenberg, B.L.

    1989-01-01

    A simple, rapid method is described for the purification of radioiodinated glucagon for use in radioimmunoassay. Samples of the radioiodinated hormone, before and after purification are analysed on polyacrylamide gel electrophoresis. The 125 I incorporation in these samples is also checked through thrichloroacetic acid precipitation. The usefulness of this labeled glucagon in radioimmunoassay is demonstrated by its biding to specific antibodies. (M.A.C.) [pt

  10. SOCIAL INEQUALITY IN CHINA AS A RESULT OF THE RAPID ECONOMIC GROWTH

    Directory of Open Access Journals (Sweden)

    Вероника Игоревна Шехурдина

    2013-12-01

    Full Text Available Since the period of openness in China, laid the foundation for more than 30 years ago, he has made remarkable progress in increasing incomes and reducing absolute poverty. However, they are caused by rising inequality. It should be noted that the rise in inequality was seen almost everywhere in the world over the past two decades. Growing dissatisfaction with the quality of economic growth is often seen in favor of certain groups more than the general population. This is clearly reflected in the growth of inequality between different groups - the rich are getting richer faster than the poor. The economic literature attributes this mainly to globalization, technological change, skills-based, and reduce the "power" of the workers. Growth model, which accompanies the last three decades to China, included a trade-off between high growth (and subsequent reduction of absolute poverty and worsening inequality. The government of China has recognized this problem and taken active steps to reduce the gap incomes and standards of living in the city and rural areas, which have already brought the first results.DOI: http://dx.doi.org/10.12731/2218-7405-2013-10-16

  11. Rapid warming accelerates tree growth decline in semi-arid forests of Inner Asia.

    Science.gov (United States)

    Liu, Hongyan; Park Williams, A; Allen, Craig D; Guo, Dali; Wu, Xiuchen; Anenkhonov, Oleg A; Liang, Eryuan; Sandanov, Denis V; Yin, Yi; Qi, Zhaohuan; Badmaeva, Natalya K

    2013-08-01

    Forests around the world are subject to risk of high rates of tree growth decline and increased tree mortality from combinations of climate warming and drought, notably in semi-arid settings. Here, we assess how climate warming has affected tree growth in one of the world's most extensive zones of semi-arid forests, in Inner Asia, a region where lack of data limits our understanding of how climate change may impact forests. We show that pervasive tree growth declines since 1994 in Inner Asia have been confined to semi-arid forests, where growing season water stress has been rising due to warming-induced increases in atmospheric moisture demand. A causal link between increasing drought and declining growth at semi-arid sites is corroborated by correlation analyses comparing annual climate data to records of tree-ring widths. These ring-width records tend to be substantially more sensitive to drought variability at semi-arid sites than at semi-humid sites. Fire occurrence and insect/pathogen attacks have increased in tandem with the most recent (2007-2009) documented episode of tree mortality. If warming in Inner Asia continues, further increases in forest stress and tree mortality could be expected, potentially driving the eventual regional loss of current semi-arid forests. © 2013 John Wiley & Sons Ltd.

  12. Feedbacks between inundation, root production, and shoot growth in a rapidly submerging brackish marsh

    Science.gov (United States)

    Kirwan, Matthew L.; Guntenspergen, Glenn R.

    2012-01-01

    1. Ecogeomorphic feedbacks between mineral sediment deposition and above-ground plant growth are thought to have dominated the evolution of many coastal ecosystems and landforms. However, land-use-related reductions in sediment delivery rates to estuaries world-wide suggest that these above-ground feedbacks may not apply in some of the world's most vulnerable coastal landscapes.

  13. Blocking rapid ice crystal growth through nonbasal plane adsorption of antifreeze proteins

    NARCIS (Netherlands)

    Olijve, L.L.C.; Meister, K.; DeVries, A.L.; Duman, J.G.; Guo, S.; Bakker, H.J.; Voets, I.K.

    2016-01-01

    Antifreeze proteins (AFPs) are a unique class of proteins that bind to growing ice crystal surfaces and arrest further ice growth. AFPs have gained a large interest for their use in antifreeze formulations for water-based materials, such as foods, waterborne paints, and organ transplants. Instead of

  14. Growth and structure of rapid thermal silicon oxides and nitroxides studied by spectroellipsometry and Auger electron spectroscopy

    Science.gov (United States)

    Gonon, N.; Gagnaire, A.; Barbier, D.; Glachant, A.

    1994-11-01

    Rapid thermal oxidation of Czochralski-grown silicon in either O2 or N2O atmospheres have been studied using spectroellipsometry and Auger electron spectroscopy. Multiwavelength ellipsometric data were processed in order to separately derive the thickness and refractive indexes of rapid thermal dielectrics. Results revealed a significant increase of the mean refractive index as the film thickness falls below 20 nm for both O2 or N2O oxidant species. A multilayer structure including an about 0.3-nm-thick interfacial region of either SiO(x) or nitroxide in the case of O2 and N2O growth, respectively, followed by a densified SiO2 layer, was found to accurately fit the experimental data. The interfacial region together with the densified state of SiO2 close to the interface suggest a dielectric structure in agreement with the continuous random network model proposed for classical thermal oxides. Auger electron spectroscopy analysis confirmed the presence of noncrystalline Si-Si bonds in the interfacial region, mostly in the case of thin oxides grown in O2. It was speculated that the initial fast growth regime was due to a transient oxygen supersaturation in the interfacial region. Besides, the self-limiting growth in N2O was confirmed and explained in agreement with several recently published data, by the early formation of a very thin nitride or oxynitride membrane in the highly densified oxide beneath the interface. The beneficial effect of direct nitrogen incorporation by rapid thermal oxidation in N2O instead of O2 for the electrical behavior of metal-oxide-semiconductor capacitors is likely a better SiO2/Si lattice accommodation through the reduction of stresses and Si-Si bonds in the interfacial region of the dielectric.

  15. Investigations on liquid phase electroepitaxial growth kinetics of GaAs

    International Nuclear Information System (INIS)

    Mouleeswaran, D.; Dhanasekaran, R.

    2004-01-01

    This paper presents a model based on solving a two-dimensional diffusion equation incorporating the electromigration effect by numerical simulation method corresponding to liquid phase electroepitaxial (LPEE) growth of GaAs, whose growth is limited by diffusion and electro migration of solute species. Using the numerical simulation method, the concentration profiles of As in Ga rich solution during the electroepitaxial growth of GaAs have been constructed in front of the growing crystal interface. Using the concentration gradient at the interface, the growth rate and thickness of the epitaxial layer of GaAs have been determined for different experimental growth conditions. The proposed model is based on the assumption that there is no convection in the solution. The results are discussed in detail

  16. Rapid and convenient semi-automated microwave-assisted solid-phase synthesis of arylopeptoids

    DEFF Research Database (Denmark)

    Rasmussen, Jakob Ewald; Boccia, Marcello Massimo; Nielsen, John

    2014-01-01

    A facile and expedient route to the synthesis of arylopeptoid oligomers (N-alkylated aminomethyl benz-amides) using semi-automated microwave-assisted solid-phase synthesis is presented. The synthesis was optimized for the incorporation of side chains derived from sterically hindered or unreactive...

  17. Rapid regulation of leaf photosynthesis, carbohydrate status and leaf area expansion to maintain growth in irregular light environments

    DEFF Research Database (Denmark)

    Kjær, Katrine Heinsvig

    2012-01-01

    to maintain carbohydrate status and growth in unpredictable light environments. Our recent results show rapid regulation of photosynthesis and leaf carbohydrate status to maintain growth and light interception in dynamic light environments when campanula, rose and chrysanthemum were grown in a cost......-efficient light control system. Plant dry matter production was in all cases linear related to DLI, despite changes in daily light duration and light intensity of supplemental light suggesting that DLI is the main limiting factor for the prediction of production time in optimal temperature conditions. The results......Protected plant productions in northern latitudes rely heavily on supplemental light use to extend the number of light hours during the day. To conserve electricity and lower costs, a low-energy input system use supplemental lights preferable during less expensive off-peak hours and turn lighting...

  18. Bulk water phase and biofilm growth in drinking water at low nutrient conditions.

    Science.gov (United States)

    Boe-Hansen, Rasmus; Albrechtsen, Hans-Jørgen; Arvin, Erik; Jørgensen, Claus

    2002-11-01

    In this study, the bacterial growth dynamics of a drinking water distribution system at low nutrient conditions was studied in order to determine bacterial growth rates by a range of methods, and to compare growth rates in the bulk water phase and the biofilm. A model distribution system was used to quantify the effect of retention times at hydraulic conditions similar to those in drinking water distribution networks. Water and pipe wall samples were taken and examined during the experiment. The pipes had been exposed to drinking water at approximately 13 degrees C, for at least 385 days to allow the formation of a mature quasi-stationary biofilm. At retention times of 12 h, total bacterial counts increased equivalent to a net bacterial growth rate of 0.048 day(-1). The bulk water phase bacteria exhibited a higher activity than the biofilm bacteria in terms of culturability, cell-specific ATP content, and cell-specific leucine incorporation rate. Bacteria in the bulk water phase incubated without the presence of biofilm exhibited a bacterial growth rate of 0.30 day(-1). The biofilm was radioactively labelled by the addition of 14C-benzoic acid. Subsequently, a biofilm detachment rate of 0.013 day(-1) was determined by measuring the release of 14C-labelled bacteria of the biofilm. For the quasi-stationary phase biofilm, the detachment rate was equivalent to the net growth rate. The growth rates determined in this study by different independent experimental approaches were comparable and within the range of values reported in the literature.

  19. Growth Phase, Oxygen, Temperature and Starvation Affect the Development of Viable but Non-Culturable State of Vibrio cholerae

    Directory of Open Access Journals (Sweden)

    Bin eWu

    2016-03-01

    Full Text Available AbstractVibrio cholerae can enter into a viable but non-culturable (VBNC state in order to survive in unfavourable environments. In this study, we studied the roles of five physicochemical and microbiological factors or states, namely, different strains, growth phases, oxygen, temperature, and starvation, on the development of VBNC of V. cholerae in artificial sea water (ASW. Different strains of the organism, the growth phase, and oxygen levels affected the progress of VBNC development. It was found that the VBNC state was induced faster in V. cholerae serogroup O1 classical biotype strain O395 than in O1 El Tor biotype strains C6706 and N16961. When cells in different growth phases were used for VBNC induction, stationary-phase cells lost their culturability more quickly than exponential-phase cells, while induction of a totally non-culturable state took longer to achieve for stationary-phase cells in all three strains, suggesting that heterogeneity of cells should be considered. Aeration strongly accelerated the loss of culturability. During the development of the VBNC state, the culturable cell count under aeration conditions was almost 106-fold lower than under oxygen-limited conditions for all three strains. The other two factors, temperature and nutrients-rich environment, may prevent the induction of VBNC cells. At 22°C or 37°C in ASW, most of the cells rapidly died and the culturable cell count reduced from about 108 CFU/mL to 106–105 CFU/mL. The total cell counts showed that cells that lost viability were decomposed, and the viable cell counts were the same as culturable cell counts, indicating that the cells did not reach the VBNC state. VBNC state development was blocked when ASW was supplied with Luria-Bertani broth (LB, but it was not affected in ASW with M9, suggesting that specific nutrients in LB may prevent the development of VBNC state. These results revealed that the five factors evaluated in this study had different

  20. Polygenic risk, rapid childhood growth, and the development of obesity: evidence from a 4-decade longitudinal study.

    Science.gov (United States)

    Belsky, Daniel W; Moffitt, Terrie E; Houts, Renate; Bennett, Gary G; Biddle, Andrea K; Blumenthal, James A; Evans, James P; Harrington, Honalee; Sugden, Karen; Williams, Benjamin; Poulton, Richie; Caspi, Avshalom

    2012-06-01

    To test how genomic loci identified in genome-wide association studies influence the development of obesity. A 38-year prospective longitudinal study of a representative birth cohort. The Dunedin Multidisciplinary Health and Development Study, Dunedin, New Zealand. One thousand thirty-seven male and female study members. We assessed genetic risk with a multilocus genetic risk score. The genetic risk score was composed of single-nucleotide polymorphisms identified in genome-wide association studies of obesity-related phenotypes. We assessed family history from parent body mass index data collected when study members were 11 years of age. Body mass index growth curves, developmental phenotypes of obesity, and adult obesity outcomes were defined from anthropometric assessments at birth and at 12 subsequent in-person interviews through 38 years of age. Individuals with higher genetic risk scores were more likely to be chronically obese in adulthood. Genetic risk first manifested as rapid growth during early childhood. Genetic risk was unrelated to birth weight. After birth, children at higher genetic risk gained weight more rapidly and reached adiposity rebound earlier and at a higher body mass index. In turn, these developmental phenotypes predicted adult obesity, mediating about half the genetic effect on adult obesity risk. Genetic associations with growth and obesity risk were independent of family history, indicating that the genetic risk score could provide novel information to clinicians. Genetic variation linked with obesity risk operates, in part, through accelerating growth in the early childhood years after birth. Etiological research and prevention strategies should target early childhood to address the obesity epidemic.

  1. The rapid growth of vertically aligned carbon nanotubes using laser heating.

    Science.gov (United States)

    Park, J B; Jeong, S H; Jeong, M S; Lim, S C; Lee, I H; Lee, Y H

    2009-05-06

    Growth of densely packed vertically aligned carbon nanotubes (VA-CNTs) using laser-induced chemical vapor deposition with visible laser (lambda = 532 nm) irradiation at room temperature is reported. Using a multiple-catalyst layer (Fe/Al/Cr) on quartz as the substrate and an acetylene-hydrogen mixture as the precursor gas, VA-CNT pillars with 60 microm height and 4 microm diameter were grown at a high rate of around 1 microm s(-1) with good reproducibility. It is demonstrated that the fabrication of uniform pillar arrays of VA-CNTs can be achieved with a single irradiation for each pillar using LCVD with no annealing or preprocessing of the substrate. Here, laser fast heating is considered the primary mechanism facilitating the growth of VA-CNT pillars. Field emission characteristics of an array of VA-CNT pillars were then examined to investigate their potential application in vacuum electronic devices.

  2. Rapid growth of seed black holes in the early universe by supra-exponential accretion.

    Science.gov (United States)

    Alexander, Tal; Natarajan, Priyamvada

    2014-09-12

    Mass accretion by black holes (BHs) is typically capped at the Eddington rate, when radiation's push balances gravity's pull. However, even exponential growth at the Eddington-limited e-folding time t(E) ~ few × 0.01 billion years is too slow to grow stellar-mass BH seeds into the supermassive luminous quasars that are observed when the universe is 1 billion years old. We propose a dynamical mechanism that can trigger supra-exponential accretion in the early universe, when a BH seed is bound in a star cluster fed by the ubiquitous dense cold gas flows. The high gas opacity traps the accretion radiation, while the low-mass BH's random motions suppress the formation of a slowly draining accretion disk. Supra-exponential growth can thus explain the puzzling emergence of supermassive BHs that power luminous quasars so soon after the Big Bang. Copyright © 2014, American Association for the Advancement of Science.

  3. Rapid and Sustained Nuclear-Cytoplasmic ERK Oscillations Induced by Epidermal Growth Factor

    Energy Technology Data Exchange (ETDEWEB)

    Shankaran, Harish; Ippolito, Danielle L.; Chrisler, William B.; Resat, Haluk; Bollinger, Nikki; Opresko, Lee K.; Wiley, H. S.

    2009-12-01

    Mathematical modeling has predicted that ERK activity should oscillate in response to cell stimulation, but this has never been observed. To explore this inconsistency, we expressed an ERK1-GFP fusion protein in mammary epithelial cells. Following EGF stimulation, we observed rapid and continuous ERK oscillations between the nucleus and cytoplasm with a periodicity of approximately 15 minutes. These oscillations were remarkably persistent (>45 cycles), displayed an asymmetric waveform, and were highly dependent on cell density, essentially disappearing at confluency. We conclude that the ERK pathway is an intrinsic oscillator. Although the functional implications of the observed oscillations are uncertain, this property can be used to continuously monitor ERK activity in single cells.

  4. Spontaneous hemorrhage simulating rapid growth of a benign subperiosteal plexiform neurofibroma

    International Nuclear Information System (INIS)

    Blitman, Netta M.; Levsky, Jeffrey M.; Thornhill, Beverly A.; Villanueva-Siles, Esperanza

    2007-01-01

    Spontaneous subperiosteal hemorrhage is a rare complication of von Recklinghausen's disease. There are few reports describing the MR imaging characteristics of this entity. Our case is unique among these as an underlying plexiform neurofibroma was visualized by MR imaging. We present a 12-year-old child with neurofibromatosis 1 who presented with a rapidly enlarging mass of the fibula. Surgery and pathology revealed subperiosteal hemorrhage into a benign, plexiform neurofibroma. The MR imaging features, pathogenesis and clinical implications of this entity are discussed. Recognition of this disease process and differentiating it from malignant transformation can prevent unnecessary surgery. (orig.)

  5. Rapid and highly efficient growth of graphene on copper by chemical vapor deposition of ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Lisi, Nicola, E-mail: nicola.lisi@enea.it [ENEA, Materials Technology Unit, Surface Technology Laboratory, Casaccia Research Centre, Via Anguillarese 301, 00123 Rome (Italy); Buonocore, Francesco; Dikonimos, Theodoros; Leoni, Enrico [ENEA, Materials Technology Unit, Surface Technology Laboratory, Casaccia Research Centre, Via Anguillarese 301, 00123 Rome (Italy); Faggio, Giuliana; Messina, Giacomo [Dipartimento di Ingegneria dell' Informazione, delle Infrastrutture e dell' Energia Sostenibile (DIIES), Università “Mediterranea” di Reggio Calabria, 89122 Reggio Calabria (Italy); Morandi, Vittorio; Ortolani, Luca [CNR-IMM Bologna, Via Gobetti 101, 40129 Bologna (Italy); Capasso, Andrea [ENEA, Materials Technology Unit, Surface Technology Laboratory, Casaccia Research Centre, Via Anguillarese 301, 00123 Rome (Italy)

    2014-11-28

    The growth of graphene by chemical vapor deposition on metal foils is a promising technique to deliver large-area films with high electron mobility. Nowadays, the chemical vapor deposition of hydrocarbons on copper is the most investigated synthesis method, although many other carbon precursors and metal substrates are used too. Among these, ethanol is a safe and inexpensive precursor that seems to offer favorable synthesis kinetics. We explored the growth of graphene on copper from ethanol, focusing on processes of short duration (up to one min). We investigated the produced films by electron microscopy, Raman and X-ray photoemission spectroscopy. A graphene film with high crystalline quality was found to cover the entire copper catalyst substrate in just 20 s, making ethanol appear as a more efficient carbon feedstock than methane and other commonly used precursors. - Highlights: • Graphene films were grown by fast chemical vapor deposition of ethanol on copper. • High-temperature/short-time growth produced highly crystalline graphene. • The copper substrate was entirely covered by a graphene film in just 20 s. • Addition of H{sub 2} had a negligible effect on the crystalline quality.

  6. Does Rapid and Sustained Economic Growth Lead to Convergence in Health Resources: The Case of China From 1980 to 2010.

    Science.gov (United States)

    Liang, Di; Zhang, Donglan; Huang, Jiayan; Schweitzer, Stuart

    2016-01-01

    China's rapid and sustained economic growth offers an opportunity to ask whether the advantages of growth diffuse throughout an economy, or remain localized in areas where the growth has been the greatest. A critical policy area in China has been the health system, and health inequality has become an issue that has led the government to broaden national health insurance programs. This study investigates whether health system resources and performance have converged over the past 30 years across China's 31 provinces. To examine geographic variation of health system resources and performance at the provincial level, we measure the degree of sigma convergence and beta convergence in indicators of health system resources (structure), health services utilization (process), and outcome. All data are from officially published sources: the China Health Statistics Year Book and the China Statistics Year Book. Sigma convergence is found for resource indicators, whereas it is not observed for either process or outcome indicators, indicating that disparities only narrowed in health system resources. Beta convergence is found in most indicators, except for 2 procedure indicators, reflecting that provinces with poorer resources were catching up. Convergence found in this study probably reflects the mixed outcome of government input, and market forces. Thus, left alone, the equitable distribution of health care resources may not occur naturally during a period of economic growth. Governmental and societal efforts are needed to reduce geographic health variation and promote health equity. © The Author(s) 2016.

  7. Analysis of a Rapidly Solidified High-Phosphorus Austenitic Steel Containing an Amorphous Phase.

    Science.gov (United States)

    1981-12-01

    electrodeposited nickel by a combination of Jet electro- polishing and ion-beam milling. Specimens were observed in a Vacuum Generators HB-5 scanning...the cell walls in these powders is one of suppressed crystal growth rather than nucleation , since the glass is formed in direct contact with the...Cohen, this Symposium. 5. T. F. Kelly, Ph.D. Thesis , MIT, February 1982. 6. C. V. Thompson, A. L. Greer, and A. J. Drehman, Proc. 4th Intl. Conf

  8. The growth and tensile deformation behavior of the silver solid solution phase with zinc

    International Nuclear Information System (INIS)

    Wu, Jiaqi; Lee, Chin C.

    2016-01-01

    The growth of homogeneous silver solid solution phase with zinc are conducted at two different compositions. X-ray diffraction (XRD) and Scanning electron microscope/Energy dispersive X-ray spectroscopy (SEM/EDX) are carried out for phase identification and chemical composition verification. The mechanical properties of silver solid solution phase with zinc are evaluated by tensile test. The engineering and true stress vs. strain curves are presented and analyzed, with those of pure silver in comparison. According to the experimental results, silver solid solution phase with zinc at both compositions show tempered yield strength, high tensile strength and large uniform strain compared to those of pure silver. Fractography further confirmed the superior ductility of silver solid solution phase with zinc at both compositions. Our preliminary but encouraging results may pave the way for the silver based alloys to be applied in industries such as electronic packaging and structure engineering.

  9. A study on fatigue crack growth in dual phase martensitic steel in air

    Indian Academy of Sciences (India)

    Dual phase (DP) steel was intercritically annealed at different temperatures from fully martensitic state to achieve martensite plus ferrite, microstructures with martensite contents in the range of 32 to 76%. Fatigue crack growth (FCG) and fracture toughness tests were carried out as per ASTM standards E 647 and E 399, ...

  10. Composition of essential oil of costmary [Balsamita major (L.) Desf.] at different growth phases

    NARCIS (Netherlands)

    Bylaite, E.; Venskutonis, R.; Roozen, J.P.; Posthumus, M.A.

    2000-01-01

    The essential oils from leaves and flowers of costmary, Balsamita major (L.) Desf. (syn. Chrysanthemum balsamita L.), were analyzed at various phases of plant growth. The highest contents of oil both in leaves and in flowers were determined before full blooming, 1.15 and 1.34øw/w), respectively.

  11. A two-phase kinetic model for fungal growth in solid-state cultivation

    NARCIS (Netherlands)

    Hamidi-Esfahani, Z.; Hejazi, P.; Abbas Shojaosadati, S.; Hoogschagen, M.J.; Vasheghani-Farahani, E.; Rinzema, A.

    2007-01-01

    A new two-phase kinetic model including exponential and logistic models was applied to simulate the growth rate of fungi at various temperatures. The model parameters, expressed as a function of temperature, were determined from the oxygen consumption rate of Aspergillus niger during cultivation on

  12. A rapid and rational approach to generating isomorphous heavy-atom phasing derivatives.

    Science.gov (United States)

    Lu, Jinghua; Sun, Peter D

    2014-09-01

    In attempts to replace the conventional trial-and-error heavy-atom derivative search method with a rational approach, we previously defined heavy metal compound reactivity against peptide ligands. Here, we assembled a composite pH- and buffer-dependent peptide reactivity profile for each heavy metal compound to guide rational heavy-atom derivative search. When knowledge of the best-reacting heavy-atom compound is combined with mass spectrometry assisted derivatization, and with a quick-soak method to optimize phasing, it is likely that the traditional heavy-atom compounds could meet the demand of modern high-throughput X-ray crystallography. As an example, we applied this rational heavy-atom phasing approach to determine a previously unknown mouse serum amyloid A2 crystal structure. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

  13. Rapid purification of diastereoisomers from Piper kadsura using supercritical fluid chromatography with chiral stationary phases.

    Science.gov (United States)

    Xin, Huaxia; Dai, Zhuoshun; Cai, Jianfeng; Ke, Yanxiong; Shi, Hui; Fu, Qing; Jin, Yu; Liang, Xinmiao

    2017-08-04

    Supercritical fluid chromatography (SFC) with chiral stationary phases (CSPs) is an advanced solution for the separation of achiral compounds in Piper kadsura. Analogues and stereoisomers are abundant in natural products, but there are obstacles in separation using conventional method. In this paper, four lignan diastereoisomers, (-)-Galbelgin, (-)-Ganschisandrin, Galgravin and (-)-Veraguensin, from Piper kadsura were separated and purified by chiral SFC. Purification strategy was designed, considering of the compound enrichment, sample purity and purification throughput. Two-step achiral purification method on chiral preparative columns with stacked automated injections was developed. Unconventional mobile phase modifier dichloromethane (DCM) was applied to improve the sample solubility. Four diastereoisomers was prepared at the respective weight of 103.1mg, 10.0mg, 152.3mg and 178.6mg from 710mg extract with the purity of greater than 98%. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. N-nitrosodimethylamine in drinking water using a rapid, solid-phase extraction method

    Energy Technology Data Exchange (ETDEWEB)

    Jenkins, S W.D. [Ministery of Environment and Energy, Etobicoke, ON (Canada). Lab. Services Branch; Koester, C J [Ministery of Environment and Energy, Etobicoke, ON (Canada). Lab. Services Branch; Taguchi, V Y [Ministery of Environment and Energy, Etobicoke, ON (Canada). Lab. Services Branch; Wang, D T [Ministery of Environment and Energy, Etobicoke, ON (Canada). Lab. Services Branch; Palmentier, J P.F.P. [Ministery of Environment and Energy, Etobicoke, ON (Canada). Lab. Services Branch; Hong, K P [Ministery of Environment and Energy, Etobicoke, ON (Canada). Lab. Services Branch

    1995-12-01

    A simple, rapid method for the extraction of N-nitrosodimethylamine (NDMA) from drinking and surface waters was developed using Ambersorb 572. Development of an alternative method to classical liquid-liquid extraction techniques was necessary to handle the workload presented by implementation of a provincial guideline of 9 ppt for drinking water and a regulatory level of 200 ppt for effluents. A granular absorbent, Ambersorb 572, was used to extract the NDMA from the water in the sample bottle. The NDMA was extracted from the Ambersorb 572 with dichloromethane in the autosampler vial. Method characteristics include a precision of 4% for replicate analyses, and accuracy of 6% at 10 ppt and a detection limit of 1.0 ppt NDMA in water. Comparative data between the Ambersorb 572 method and liquid-liquid extraction showed excellent agreement (average difference of 12%). With the Ambersorb 572 method, dichloromethane use has been reduced by a factor of 1,000 and productivity has been increased by a factor of 3-4. Monitoring of a drinking water supply showed rapidly changing concentrations of NDMA from day to day. (orig.)

  15. Rapid liquid phase sintered Mn doped BiFeO3 ceramics with enhanced polarization and weak magnetization

    Science.gov (United States)

    Kumar, Manoj; Yadav, K. L.

    2007-12-01

    Single-phase BiFe1-xMnxO3 multiferroic ceramics have been synthesized by rapid liquid phase sintering method to study the influence of Mn substitution on their crystal structure, dielectric, magnetic, and ferroelectric behaviors. From XRD analysis it is seen that Mn substitution does not affect the crystal structure of the BiFe1-xMnxO3 system. An enhancement in magnetization was observed for BiFe1-xMnxO3 ceramics. However, the ferooelectric hysteresis loops were not really saturated, we observed a spontaneous polarization of 10.23μC /cm2 under the applied field of 42kV/cm and remanent polarization of 3.99μC/cm2 for x =0.3 ceramic.

  16. Early cytokine modulation after the rapid induction phase of sublingual immunotherapy with mite monomeric allergoids.

    Science.gov (United States)

    Di Gioacchino, M; Perrone, A; Petrarca, C; Di Claudio, F; Mistrello, G; Falagiani, P; Dadorante, V; Verna, N; Braga, M; Ballone, E; Cavallucci, E

    2008-01-01

    The influence of different treatment schedules of sublingual immunotherapy (SLIT) in activating IL-10-producing T-cells, crucial in inducing allergen-specific tolerance, is not completely understood. The present work was designed to evaluate allergen driven interleukin release by mononuclear cells in the early phase of SLIT, after application of different induction schemes. Twenty mite-allergic patients were enrolled, 10 (group A) treated with a traditional 98 day induction scheme and 10 (group B) with a 16 day scheme with monomeric allergoid vaccine. At the end of the induction phase, the cumulative doses taken by group A and group B patients were equivalent to 50.5 and 50.3 microg of mite group 1 allergens, respectively. The release of Th1-, Th2- and Treg-related interleukins was assessed in culture supernatants of 5 microg/ml Der-p1-stimulated mononuclear cells, isolated before and after the induction phases. No relevant treatment-related side effects were observed. Interleukin release was similar in the two groups at the enrolment. Non-stimulated and Der p 1 stimulated release of studied cytokines was similar in the two groups at enrolment. Der p 1 stimulation significantly increased IL-10 release (pallergoids are utilized.

  17. Interaction Between Second-Phase Particle Dissolution and Abnormal Grain Growth in an Austenitic Stainless Steel

    Directory of Open Access Journals (Sweden)

    Dutra J.C.

    2002-01-01

    Full Text Available The continuing development of stainless steels has resulted in complex steel compositions with substantial amounts of alloying elements. The benefits of such additions invariably come attached to unavoidable disadvantages. One of the most critical item is the potential microstructural instability of the material. Alloying elements may be in a supersaturated solid solution, in which the precipitation of carbides, nitrides, borides and intermetallic phases occurs in a wide range of temperatures. In order to dissolve the mentioned precipitates, solution annealing is commonly performed. However, at the temperature range in which this treatment is carried out, the onset of abnormal grain growth can occur. The interaction between the dissolution of these second-phase particles and the occurrence of abnormal grain growth is investigated in this work. This study also shows that the thermodynamics and the kinetics of dissolution of precipitates may be used to predict whether abnormal grain growth takes place.

  18. The Effects of Temperature and Growth Phase on the Lipidomes of Sulfolobus islandicus and Sulfolobus tokodaii

    DEFF Research Database (Denmark)

    Jensen, Sara Munk; Neesgaard, Vinnie Lund; Skjoldbjerg, Sandra Landbo Nedergaard

    2015-01-01

    at three different temperatures, with samples withdrawn during lag, exponential, and stationary phases. Three abundant tetraether lipid classes and one diether lipid class were monitored. Beside the expected increase in the number of cyclopentane moieties with higher temperature in both archaea, we......The functionality of the plasma membrane is essential for all organisms. Adaption to high growth temperatures imposes challenges and Bacteria, Eukarya, and Archaea have developed several mechanisms to cope with these. Hyperthermophilic archaea have earlier been shown to synthesize tetraether...... membrane lipids with an increased number of cyclopentane moieties at higher growth temperatures. Here we used shotgun lipidomics to study this effect as well as the influence of growth phase on the lipidomes of Sulfolobus islandicus and Sulfolobus tokodaii for the first time. Both species were cultivated...

  19. Controlling Growth High Uniformity Indium Selenide (In2Se3) Nanowires via the Rapid Thermal Annealing Process at Low Temperature.

    Science.gov (United States)

    Hsu, Ya-Chu; Hung, Yu-Chen; Wang, Chiu-Yen

    2017-09-15

    High uniformity Au-catalyzed indium selenide (In 2 Se 3) nanowires are grown with the rapid thermal annealing (RTA) treatment via the vapor-liquid-solid (VLS) mechanism. The diameters of Au-catalyzed In 2 Se 3 nanowires could be controlled with varied thicknesses of Au films, and the uniformity of nanowires is improved via a fast pre-annealing rate, 100 °C/s. Comparing with the slower heating rate, 0.1 °C/s, the average diameters and distributions (standard deviation, SD) of In 2 Se 3 nanowires with and without the RTA process are 97.14 ± 22.95 nm (23.63%) and 119.06 ± 48.75 nm (40.95%), respectively. The in situ annealing TEM is used to study the effect of heating rate on the formation of Au nanoparticles from the as-deposited Au film. The results demonstrate that the average diameters and distributions of Au nanoparticles with and without the RTA process are 19.84 ± 5.96 nm (30.00%) and about 22.06 ± 9.00 nm (40.80%), respectively. It proves that the diameter size, distribution, and uniformity of Au-catalyzed In 2 Se 3 nanowires are reduced and improved via the RTA pre-treated. The systemic study could help to control the size distribution of other nanomaterials through tuning the annealing rate, temperatures of precursor, and growth substrate to control the size distribution of other nanomaterials. Graphical Abstract Rapid thermal annealing (RTA) process proved that it can uniform the size distribution of Au nanoparticles, and then it can be used to grow the high uniformity Au-catalyzed In 2 Se 3 nanowires via the vapor-liquid-solid (VLS) mechanism. Comparing with the general growth condition, the heating rate is slow, 0.1 °C/s, and the growth temperature is a relatively high growth temperature, > 650 °C. RTA pre-treated growth substrate can form smaller and uniform Au nanoparticles to react with the In 2 Se 3 vapor and produce the high uniformity In 2 Se 3 nanowires. The in situ annealing TEM is used to realize the effect of heating

  20. Modifying effect of caffeine on cell radiosensitivity in stationary and logarithmic phases of growth

    International Nuclear Information System (INIS)

    Plotnikova, E.D.; Kostenko, G.A.

    1978-01-01

    Studied was reproductive killing of cultivated fibroblasts of a Chinese hamster in stationary and exponential growth phases after gamma irradiation. After cell irradiation in a stationary phase at 1200 rad dose rate and postirradiation incubation in conditioned medium before resowing for 5 hrs the survival rate increased almost 5 times due to the reparation of potential-lethal injuries. Under sodium caffein-benzoate (4 mg/ml) effect on cells in a stationary growth phase for 5 hrs before irradiation the survival rate increased; protection level was almost the same as in case of reduction in a conditioned media. Modification factor of dose curve incline was 1.3. Caffein protective effect may be conjectured to relate to the inhibition of potentially-lethal injury fraction realization

  1. Rapid growth in early childhood associated with young adult overweight and obesity--evidence from a community based cohort study.

    Science.gov (United States)

    Sutharsan, Ratneswary; O'Callaghan, Michael J; Williams, Gail; Najman, Jake M; Mamun, Abdullah A

    2015-08-08

    Rapid weight gain in early life may increase the risk of overweight and obesity in adulthood. We investigated the association between the rate of growth during early childhood and the development of overweight and obesity in young adults. We used a prospective cohort study of 2077 young adults who were born between 1981 and 1984 in Brisbane, Australia and had anthropometry measurements available at birth, 6 months, 5 years, 14 years and 21 years of age. The associations of rate of early growth with body mass index (BMI), waist circumference (WC) and waist-to-hip ratio (WHR) and their categories at 21 years were studied using multivariate analysis. We found that rapid weight gain [> + 0.67 standard deviation score (SDS)] in the first 5 years of life was associated with young adults' overweight status (BMI: adjusted OR = 2.35, 95% CI, 1.82-3.03; WC: adjusted OR = 2.20, 95% CI, 1.65-2.95). We also observed that slow weight gain in the first 5 years of age (young adulthood, in contrast slow weight gain was inversely associated with weight status at 21 years.

  2. Rapid growth of zinc oxide nanobars in presence of electric field by physical vapor deposition

    Science.gov (United States)

    Jouya, Mehraban; Taromian, Fahime; Siami, Simin

    2017-12-01

    In this contribution, electric field has some effects to increase growth for specific time duration on zinc oxide (ZnO) nanobars. First, the zinc (Zn) thin film has been prepared by 235,000 V/m electric field assisted physical vapor deposition (PVD) at vacuum of 1.33 × 10-5 mbar. Second, strong electric field of 134,000 V/m has been used in ambient for growing ZnO nanobars in term of the time include 2.5 and 10 h. The performances of the ZnO nanostructure in absence and presence of electric field have been determined by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results of XRD analysis showed that ZnO has a hexagonal bars structure and a strongly preferred (101) orientation which is strongest than without applying electric field. SEM analysis revealed that physical vapored ZnO thin film in presence of electric field are densely packed with uniform morphological, thinner and denser in distribution. Electric field effect for ZnO growth in 2.5 h is better than it in the 2.5 h without electric field but by passing the time the media influence has good power almost as same as electric field. Through this electric field in PVD, the compact and uniform Zn film has been achieved which is less diameter than ordinary PVD method. Finally, we carry out a series of experiments to grow different-orientation ZnO nanobars with less than 100 nm in diameter, which are the time saving process in base of PVD ever reported. Therefore, the significant conclusion in usage electric field is reducing time of growth.

  3. Rapid gut growth but persistent delay in digestive function in the postnatal period of preterm pigs

    DEFF Research Database (Denmark)

    Hansen, Carl Frederik; Thymann, Thomas; Andersen, Anders Daniel

    2016-01-01

    BACKGROUND: Preterm infants often tolerate full enteral nutrition few weeks after birth but it is not known how this is related to gut maturation. Using pigs as models, we hypothesized that intestinal structure and digestive function are similar in preterm and term individuals at 3-4 weeks after...... to term pigs. CONCLUSION: Intestinal structure shows a remarkable growth adaptation in the first week after preterm birth, especially with enteral nutrition, while some digestive functions remain immature until at least 3-4 weeks. It is important to identify feeding regimens that stimulate intestinal...

  4. Monte carlo simulation of anisotropic grain growth in liquid phase sintering

    International Nuclear Information System (INIS)

    Han, Yoon Soo; Kim, Do Kyung

    2003-01-01

    One of the key techniques in modern engineering ceramic system is microstructural control of anisotropic grain growth because grain orientation and shape proved to have an influence on mechanic, dielectric and electric behavior of ceramics. But until now, computer simulation for grain growth has not sufficiently addressed to this subject. The reason is that simulation algorithm was laborious because it has to contain mass transfer through liquid phase and especially anisotropic grain growth has to be considered based on interfacial properties in real system. The goal of present study is simulation of anisotropic grain growth in liquid phase by Q-states model. To give anisotropic inherency to grains, constraint on mobility to specific boundaries was applied. For comparison, we measured grain size distribution and deduced grain growth kinetics from relation ship between average grain size and time. As a result, the grain size distribution functions become broader and the peak height decreases as the anisotropy is increased. The growth exponent 0.67 and 0.47 found by linear fitting have slightly different values in comparison with work of Grest et al. but similar is trend to the decrease of exponent with anisotropy

  5. Investigations on the growth kinetics of Laves phase precipitates in 12% Cr creep-resistant steels: Experimental and DICTRA calculations

    International Nuclear Information System (INIS)

    Prat, O.; Garcia, J.; Rojas, D.; Carrasco, C.; Inden, G.

    2010-01-01

    The growth kinetics of Laves phase precipitates (type Fe 2 W) in the early stage of creep (650 deg. C for 10,000 h) in two 12% Cr ferrite-martensitic steels has been investigated. In one alloy the Laves phase formed on tempering, while in the second alloy the Laves phase precipitated during creep. Kinetic simulations were performed using the software DICTRA. The particle size of the Laves phase was measured on transmission electron microscopy samples. The equilibrium phase fraction of the Laves phase was reached in the first thousand hours. Simulations of particle growth showed good agreement with the experimental results. Competitive growth between M 23 C 6 and the Laves phase showed that M 23 C 6 carbides reached their equilibrium after 12 days, whereas the Laves phase reached equilibrium after 3 months. Simulations of the influence of the interfacial energy and addition of Co, Cu and Si on Laves phase precipitation are presented.

  6. Fertility in Alberta in a Context of Rapid Economic Growth, 1997-2007

    Directory of Open Access Journals (Sweden)

    Frank Trovato

    2010-12-01

    Full Text Available Historically, birth rates in Alberta have followed closely the trajectory of change experienced by the other Canadian provinces. Its total fertility rate fell during the low point of the 1930s; it increased during the post-War baby boom in the 1950s and sixties, and thereafter fell to subreplacement levels beginning in the mid 1970s. In recent years, especially since the early 2000s, the birth rate in Alberta has unexpectedly increased, such that by 2007, it had reached 1.90 children per woman - not far from the 2.1 level needed for generational replacement in the long term. During this same period both national and provincial fertility rates fluctuated at levels below those of Alberta (except Saskatchewan and Manitoba, whose rates have been higher. In this study, I examine the historical pattern of fertility change in Alberta, noting similarities and differences with the other provinces. I then look at the association of selected macro level factors (marriage, unemployment, wages, female labour force participation with change in total and parity-specific birth rates between 1997 and 2007, a period of unprecedented economic growth in Alberta. The statistical results show that although marriage is not significantly correlated with change in fertility rates, male and female wages and female labour force participation all show associations consistent with a procyclical interpretation of fertility change - that is, periods of economic growth are conducive to fertility increase whereas bad economic times are associated with reduced fertility.

  7. Fertility in Alberta in a Context of Rapid Economic Growth, 1997-2007

    Directory of Open Access Journals (Sweden)

    Frank Trovato

    2010-01-01

    Full Text Available Historically, birth rates in Alberta have followed closely the trajectory of change experienced by the other Canadian provinces. Its total fertility rate fell during the low point of the 1930s; it increased during the post-War baby boom in the 1950s and sixties, and thereafter fell to sub-replacement levels beginning in the mid 1970s. In recent years, especially since the early 2000s, the birth rate in Alberta has unexpectedly increased, such that by 2007, it had reached 1.90 children per woman---not far from the 2.1 level needed for generational replacement in the long term. During this same period both national and provincial fertility rates fluctuated at levels below those of Alberta (except Saskatchewan and Manitoba, whose rates have been higher. In this study, I examine the historical pattern of fertility change in Alberta, noting similarities and differences with the other provinces. I then look at the association of selected macro level factors (marriage, unemployment, wages, female labour force participation with change in total and parity-specific birth rates between 1997 and 2007, a period of unprecedented economic growth in Alberta. The statistical results show that although marriage is not significantly correlated with change in fertility rates, male and female wages and female labour force participation all show associations consistent with a procyclical interpretation of fertility change --- that is, periods of economic growth are conducive to fertility increase whereas bad economic times lead to reduced fertility.

  8. Rapid growth of ZnO hexagonal prism crystals by direct microwave heating

    Institute of Scientific and Technical Information of China (English)

    ZHU Zhenqi; ZHOU Jian; LIU Guizhen; REN Zhiguo

    2008-01-01

    ZnO hexagonal prism crystals were synthesized from ZnO powders by microwave heating in a short time (within 20 min) without any metal catalyst or transport agent.Zinc oxide raw materials were made by evaporating from the high-temperature zone in an enclosure atmosphere and crystals were grown on the self-source substrate.The inherent asymmetry in microwave heating provides the temperature gradient for crystal growth.Substrate and temperature distribution in the oven show significant effects on the growth of the ZnO crystal.The morphologies demonstrate that these samples are pure hexagonal prism crystals with maximum 80 μm in diameter and 600 μm in length,which possess a well faceted end and side surface.X-ray diffraction (XRD) reveals that these samples are pure crystals.The photoluminescence (PL) exhibits strong ultraviolet emission at room temperature,indicating potential applications for short-wave light-emitting photonic devices.

  9. Monitoring of Water Spectral Pattern Reveals Differences in Probiotics Growth When Used for Rapid Bacteria Selection.

    Directory of Open Access Journals (Sweden)

    Aleksandar Slavchev

    Full Text Available Development of efficient screening method coupled with cell functionality evaluation is highly needed in contemporary microbiology. The presented novel concept and fast non-destructive method brings in to play the water spectral pattern of the solution as a molecular fingerprint of the cell culture system. To elucidate the concept, NIR spectroscopy with Aquaphotomics were applied to monitor the growth of sixteen Lactobacillus bulgaricus one Lactobacillus pentosus and one Lactobacillus gasseri bacteria strains. Their growth rate, maximal optical density, low pH and bile tolerances were measured and further used as a reference data for analysis of the simultaneously acquired spectral data. The acquired spectral data in the region of 1100-1850nm was subjected to various multivariate data analyses - PCA, OPLS-DA, PLSR. The results showed high accuracy of bacteria strains classification according to their probiotic strength. Most informative spectral fingerprints covered the first overtone of water, emphasizing the relation of water molecular system to cell functionality.

  10. Chemical evolution of the Galaxy at the initial rapid-collapse phase

    Energy Technology Data Exchange (ETDEWEB)

    Caimmi, R [Padua Univ. (Italy). Istituto di Astronomia

    1978-04-01

    Equations for the chemical evolution of the Galaxy are derived, accounting for (i) the dynamical evolution of the Galaxy (i.e. the collapse of the proto-galaxy) and (ii) either a variable mass-spectrum in the birth-rate stellar function of the type B(m,t) = psi(t)phi(m,t), or a constant mass-spectrum with variable lower mass limit for star birth: msub(mf) = msub(mf)(Z). Simple equations are adopted for the collapse of the proto-galaxy, accounting for the experimental data (i.e. axial ratio and major semi-axis) relative to the halo and to the disk, and best fitted for a rapid collapse; gas density is assumed to be always uniform. Numerical computations of several cases show that there is qualitative agreement with the experimental data relative to the Z(t) function when: (i) the mass-spectrum is nearly constant in time: phi(m,t) approximately phi(m) = msup(-2.35); (ii) the efficiency phi(t) proportional to rhosup(..cap alpha..) is sufficiently high; moreover, the super metallic effect (SME) takes place for ..cap alpha.. greater than a given value (..cap alpha.. > approximately 1.5); (iii) the shorter the collapse time Tsub(c), the more rapid is the initial increase of metallicity, the asymptotic value being left nearly unaltered. The theoretical results are not in complete agreement with the observed data bearing on the Nsub(n)(Z) function (Nsub(n) is the number of stars whose Main-Sequence lifetime is not less than the age of the Galaxy), while a hypothesis of star formation with different efficiencies in different zones of the Galaxy, and successive stellar mixing from zone to zone, is not inconsistent with such data.

  11. Chemical evolution of the Galaxy at the initial rapid-collapse phase

    International Nuclear Information System (INIS)

    Caimmi, R.

    1978-01-01

    Equations for the chemical evolution of the Galaxy are derived, accounting for (i) the dynamical evolution of the Galaxy (i.e. the collapse of the proto-galaxy) and (ii) either a variable mass-spectrum in the birth-rate stellar function of the type B(m,t) = psi(t)phi(m,t), or a constant mass-spectrum with variable lower mass limit for star birth: msub(mf) = msub(mf)(Z). Simple equations are adopted for the collapse of the proto-galaxy, accounting for the experimental data (i.e. axial ratio and major semi-axis) relative to the halo and to the disk, and best fitted for a rapid collapse; gas density is assumed to be always uniform. Numerical computations of several cases show that there is qualitative agreement with the experimental data relative to the Z(t) function when: (i) the mass-spectrum is nearly constant in time: phi(m,t) approximately phi(m) = msup(-2.35); (ii) the efficiency phi(t) proportional to rhosup(α) is sufficiently high; moreover, the super metallic effect (SME) takes place for α greater than a given value (α > approximately 1.5); (iii) the shorter the collapse time Tsub(c), the more rapid is the initial increase of metallicity, the asymptotic value being left nearly unaltered. The theoretical results are not in complete agreement with the observed data bearing on the Nsub(n)(Z) function (Nsub(n) is the number of stars whose Main-Sequence lifetime is not less than the age of the Galaxy), while a hypothesis of star formation with different efficiencies in different zones of the Galaxy, and successive stellar mixing from zone to zone, is not inconsistent with such data. (Auth.)

  12. Phase competition in the growth of SrCoOx/LaAlO3 thin films

    Directory of Open Access Journals (Sweden)

    Jie Zhang

    2018-02-01

    Full Text Available The reversible topotactic phase transformation between brownmillerite SrCoO2.5 to perovskite SrCoO3 has attracted more and more attention for potential applications as solid oxide fuels and electrolysis cells. However, the relatively easy transformation result from small thermal stable energy barriers between the two phases leads to unstable the structures. In the paper, amounts of SrCoO3-δ films have been prepared by pulsed laser deposition at optimized growth conditions with the temperature range of 590-720°C. The X-ray diffraction (XRD results demonstrated that a phase competition emerged around 650°C. The Gibbs free energies of two phases at high temperature revealed the difference of stability of these two phases under different growth temperature. The optical spectroscopies and X-ray photoelectron spectroscopies were used to verify the electronic structure and chemical state differences between the two phases with distinct crystal structures.

  13. Solid-state diffusion-controlled growth of the phases in the Au-Sn system

    Science.gov (United States)

    Baheti, Varun A.; Kashyap, Sanjay; Kumar, Praveen; Chattopadhyay, Kamanio; Paul, Aloke

    2018-01-01

    The solid state diffusion-controlled growth of the phases is studied for the Au-Sn system in the range of room temperature to 200 °C using bulk and electroplated diffusion couples. The number of product phases in the interdiffusion zone decreases with the decrease in annealing temperature. These phases grow with significantly high rates even at the room temperature. The growth rate of the AuSn4 phase is observed to be higher in the case of electroplated diffusion couple because of the relatively small grains and hence high contribution of the grain boundary diffusion when compared to the bulk diffusion couple. The diffraction pattern analysis indicates the same equilibrium crystal structure of the phases in these two types of diffusion couples. The analysis in the AuSn4 phase relating the estimated tracer diffusion coefficients with grain size, crystal structure, the homologous temperature of experiments and the concept of the sublattice diffusion mechanism in the intermetallic compounds indicate that Au diffuses mainly via the grain boundaries, whereas Sn diffuses via both the grain boundaries and the lattice.

  14. A rapid solid-phase extraction fluorometric method for thiamine and riboflavin in salmonid eggs

    Science.gov (United States)

    Zajicek, James L.; Tillitt, Donald E.; Brown, Scott B.; Brown, Lisa R.; Honeyfield, Dale C.; Fitzsimons, John D.

    2005-01-01

    A new method has been developed and successfully applied to the selective measurement of thiamine (nonphosphorylated), total thiamine (sum of thiamine, thiamine monophosphate [TMP], thiamine diphosphate [TDP], and thiamine triphosphate [TTP]), and potentially interfering riboflavin in acidic (2% trichloroacetic acid) extracts of selected salmonid and walleye egg samples. Acidic extracts of eggs were applied directly to end-capped C18, reversed-phase solid-phase extraction (SPE) columns and separated into three fractions by elution with mixtures of PO4 buffer (pH 2), methanol (10%), and acetonitrile (20%). All thiamine compounds recovered in the first two fractions were oxidized to their corresponding thiochromes with alkaline potassium hexacyanoferrate, and we measured the thiochrome fluorescence (excitation at 360 nm, emission at 460 nm) in a 96-well microplate reader. Riboflavin, recovered in third fraction (eluted with pH 2, 20% acetonitrile), was analyzed directly by measuring the fluorescence of this fraction (excitation at 450 nm, emission at 530 nm). Significant portions of the phosphate esters of thiamine (TMP, TDP, and presumably TTP), when present at low concentrations (extract thiamine compounds into 2% trichlororacetic acid solution; an inexpensive, commercially available SPE column; small amounts of sample (0.5-1 g); microliter volumes of solvents per sample; a traditional, relatively nonhazardous, oxidation of thiamine compounds to fluorescent thiochromes; and an ultraviolet-visible-wavelength-filter fluorometer for the measurements. ?? Copyright by the American Fisheries Society 2005.

  15. Effect of algal growth phase on Aureococcus anophagefferens susceptibility to hydrogen peroxide

    Energy Technology Data Exchange (ETDEWEB)

    Randhawa, Varunpreet; Thakkar, Megha; Wei, Liping, E-mail: liping.wei@njit.edu

    2013-10-15

    Highlights: •Brown tide alga's susceptibility to H{sub 2}O{sub 2} was examined via growth and physiology responses. •The study was designed equalizing the influence of the media and cell density in test cultures. •Stationary cells was more sensitive to H{sub 2}O{sub 2} than exponential cells. •Stationary cells showed weaker non-protein thiol up-regulation than exponential cells. •Stationary cells mediated greater H{sub 2}O{sub 2} decomposition than exponential cells did. -- Abstract: A cell's growth phase could affect its susceptibility to a biocide in microbial control. This study examines the growth phase dependent susceptibility of a brown tide bloom alga Aureococcus anophagefferens to microbial biocide hydrogen peroxide (H{sub 2}O{sub 2}). Test cultures of A. anophagefferens cells in exponential and stationary growth phase and similar initial cell density (1.6 × 10{sup 6} cells mL{sup −1}) were exposed to 0.4–1.6 mg L{sup −1} H{sub 2}O{sub 2}. Changes in algal growth (in vivo fluorescence, total chlorophyll a, and cell density), cell physiology (maximum quantum yield of photosystem II, and total intracellular non-protein thiols), and H{sub 2}O{sub 2} decomposition were quantified. Results show that the stationary phase cells are more susceptible to H{sub 2}O{sub 2} than the exponential phase cells, and this is attributed to the weaker ROS (reactive oxygen species) scavenging system and consequently greater cell damage in stationary phase cells. The stationary phase cells potentially require 30–40% less H{sub 2}O{sub 2} to reach 90% removal within 12 h of treatment as compared to the exponential phase cells. The results have practical implications in brown tide bloom control with respect to the timing and the dosage of H{sub 2}O{sub 2} application.

  16. Exploring features and opportunities of rapid-growth wine firms in Chile

    Directory of Open Access Journals (Sweden)

    Jorge J. Román

    2017-04-01

    Full Text Available While much has been studied regarding the wine industry in Spain and France, little has been studied in developing countries. The aim of this work is to study the characteristics of dynamic wine firms in Chile. This paper presents qualitative research and reports six cases of wine companies, where several variables are analyzed according to Barringer, Jones and Neubaum framework. These variables include prior experience, founders’ knowledge regarding large company management, the use of strategic-planning systems and the use of new technology in the majority of its production. The results of this research could prove insightful for wine entrepreneurs looking to enhance their growth, based on greater differentiation and innovation, and not only on being competitive in pricing.

  17. A multiplexed microfluidic toolbox for the rapid optimization of affinity-driven partition in aqueous two phase systems.

    Science.gov (United States)

    Bras, Eduardo J S; Soares, Ruben R G; Azevedo, Ana M; Fernandes, Pedro; Arévalo-Rodríguez, Miguel; Chu, Virginia; Conde, João P; Aires-Barros, M Raquel

    2017-09-15

    Antibodies and other protein products such as interferons and cytokines are biopharmaceuticals of critical importance which, in order to be safely administered, have to be thoroughly purified in a cost effective and efficient manner. The use of aqueous two-phase extraction (ATPE) is a viable option for this purification, but these systems are difficult to model and optimization procedures require lengthy and expensive screening processes. Here, a methodology for the rapid screening of antibody extraction conditions using a microfluidic channel-based toolbox is presented. A first microfluidic structure allows a simple negative-pressure driven rapid screening of up to 8 extraction conditions simultaneously, using less than 20μL of each phase-forming solution per experiment, while a second microfluidic structure allows the integration of multi-step extraction protocols based on the results obtained with the first device. In this paper, this microfluidic toolbox was used to demonstrate the potential of LYTAG fusion proteins used as affinity tags to optimize the partitioning of antibodies in ATPE processes, where a maximum partition coefficient (K) of 9.2 in a PEG 3350/phosphate system was obtained for the antibody extraction in the presence of the LYTAG-Z dual ligand. This represents an increase of approx. 3.7 fold when compared with the same conditions without the affinity molecule (K=2.5). Overall, this miniaturized and versatile approach allowed the rapid optimization of molecule partition followed by a proof-of-concept demonstration of an integrated back extraction procedure, both of which are critical procedures towards obtaining high purity biopharmaceuticals using ATPE. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Rapid Quantification of the Toxic Alga Prymnesium parvum in Natural Samples by Use of a Specific Monoclonal Antibody and Solid-Phase Cytometry

    DEFF Research Database (Denmark)

    West, N. J.; Bacchieri, R.; Hansen, Gert

    2006-01-01

    The increasing incidence of harmful algal blooms around the world and their associated health and economic effects require the development of methods to rapidly and accurately detect and enumerate the target species. Here we describe use of a solid-phase cytometer to detect and enumerate the toxi......-phase cytometer can be used to rapidly enumerate natural P. parvum cells and that it could be used to detect other toxic algae, with an appropriate antibody or DNA probe....

  19. Epitaxial growth of Ge-Sb-Te based phase change materials

    Energy Technology Data Exchange (ETDEWEB)

    Perumal, Karthick

    2013-07-30

    Ge-Sb-Te based phase change materials are considered as a prime candidate for optical and electrical data storage applications. With the application of an optical or electrical pulse, they can be reversibly switched between amorphous and crystalline state, thereby exhibiting large optical and electrical contrast between the two phases, which are then stored as information in the form of binary digits. Single crystalline growth is interesting from both the academic and industrial perspective, as ordered Ge-Sb-Te based metamaterials are known to exhibit switching at reduced energies. The present study deals with the epitaxial growth and analysis of Ge-Sb-Te based thin films. The first part of the thesis deals with the epitaxial growth of GeTe. Thin films of GeTe were grown on highly mismatched Si(111) and (001) substrates. On both the substrate orientations the film grows along [111] direction with an amorphous-to-crystalline transition observed during the initial stages of growth. The amorphous-to-crystalline transition was studied in-vivo using azimuthal reflection high-energy electron diffraction scans and grazing incidence X-ray diffraction. In the second part of the thesis epitaxy and characterization of Sb{sub 2}Te{sub 3} thin films are presented. The third part of the thesis deals with the epitaxy of ternary Ge-Sb-Te alloys. The composition of the films are shown to be highly dependent on growth temperatures and vary along the pseudobinary line from Sb{sub 2}Te{sub 3} to GeTe with increase in growth temperatures. A line-of-sight quadrupole mass spectrometer was used to reliably control the GeSbTe growth temperature. Growth was performed at different Ge, Sb, Te fluxes to study the compositional variation of the films. Incommensurate peaks are observed along the [111] direction by X-ray diffraction. The possibility of superstructural vacancy ordering along the [111] direction is discussed.

  20. Epitaxial growth of Ge-Sb-Te based phase change materials

    International Nuclear Information System (INIS)

    Perumal, Karthick

    2013-01-01

    Ge-Sb-Te based phase change materials are considered as a prime candidate for optical and electrical data storage applications. With the application of an optical or electrical pulse, they can be reversibly switched between amorphous and crystalline state, thereby exhibiting large optical and electrical contrast between the two phases, which are then stored as information in the form of binary digits. Single crystalline growth is interesting from both the academic and industrial perspective, as ordered Ge-Sb-Te based metamaterials are known to exhibit switching at reduced energies. The present study deals with the epitaxial growth and analysis of Ge-Sb-Te based thin films. The first part of the thesis deals with the epitaxial growth of GeTe. Thin films of GeTe were grown on highly mismatched Si(111) and (001) substrates. On both the substrate orientations the film grows along [111] direction with an amorphous-to-crystalline transition observed during the initial stages of growth. The amorphous-to-crystalline transition was studied in-vivo using azimuthal reflection high-energy electron diffraction scans and grazing incidence X-ray diffraction. In the second part of the thesis epitaxy and characterization of Sb 2 Te 3 thin films are presented. The third part of the thesis deals with the epitaxy of ternary Ge-Sb-Te alloys. The composition of the films are shown to be highly dependent on growth temperatures and vary along the pseudobinary line from Sb 2 Te 3 to GeTe with increase in growth temperatures. A line-of-sight quadrupole mass spectrometer was used to reliably control the GeSbTe growth temperature. Growth was performed at different Ge, Sb, Te fluxes to study the compositional variation of the films. Incommensurate peaks are observed along the [111] direction by X-ray diffraction. The possibility of superstructural vacancy ordering along the [111] direction is discussed.

  1. Rapid blockade of telomerase activity and tumor cell growth by the DPL lipofection of ribbon antisense to hTR.

    Science.gov (United States)

    Bajpai, Arun K; Park, Jeong-Hoh; Moon, Ik-Jae; Kang, Hyungu; Lee, Yun-Han; Doh, Kyung-Oh; Suh, Seong-Il; Chang, Byeong-Churl; Park, Jong-Gu

    2005-09-29

    Ribbon antisense (RiAS) to the hTR RNA, a component of the telomerase complex, was employed to inhibit telomerase activity and cancer cell growth. The antisense molecule, hTR-RiAS, combined with enhanced cellular uptake was shown to effectively inhibit telomerase activity and cause rapid cell death in various cancer cell lines. When cancer cells were treated with hTR-RiAS, the level of hTR RNA was reduced by more than 90% accompanied with reduction in telomerase activity. When checked for cancer cell viability, cancer cell lines treated with hTR-RiAS using DNA+Peptide+Lipid complex showed 70-80% growth inhibition in 3 days. The reduced cell viability was due to apoptosis as the percentage of cells exhibiting the sub-G0 arrest and DNA fragmentation increased after antisense treatment. Further, when subcutaneous tumors of a colon cancer cell line (SW480) were treated intratumorally with hTR-RiAS, tumor growth was markedly suppressed with almost total ablation of hTR RNA in the tumor tissue. Cells in the tumor tissue were also found to undergo apoptosis after hTR-RiAS treatment. These results suggest that hTR-RiAS is an effective anticancer reagent, with a potential for broad efficacy to diverse malignant tumors.

  2. Theory and modeling of microstructural evolution in polycrystalline materials: Solute segregation, grain growth and phase transformations

    Science.gov (United States)

    Ma, Ning

    2005-11-01

    To accurately predict microstructure evolution and, hence, to synthesis metal and ceramic alloys with desirable properties involves many fundamental as well as practical issues. In the present study, novel theoretical and phase field approaches have been developed to address some of these issues including solute drag and segregation transition at grain boundaries and dislocations, grain growth in systems of anisotropic boundary properties, and precipitate microstructure development in polycrystalline materials. The segregation model has allowed for the prediction of a first-order segregation transition, which could be related to the sharp transition of solute concentration of grain boundary as a function of temperature. The incorporating of interfacial energy and mobility as functions of misorientation and inclination in the phase field model has allowed for the study of concurrent grain growth and texture evolution. The simulation results were analyzed using the concept of local grain boundary energy density, which simplified significantly the development of governing equations for texture controlled grain growth in Ti-6Al-4V. Quantitative phase field modeling techniques have been developed by incorporating thermodynamic and diffusivity databases. The models have been validated against DICTRA simulations in simple 1D problems and applied to simulate realistic microstructural evolutions in Ti-6Al-4V, including grain boundary a and globular a growth and sideplate development under both isothermal aging and continuous cooling conditions. The simulation predictions agree well with experimental observations.

  3. Rapid colorimetric sensing of tetracycline antibiotics with in situ growth of gold nanoparticles

    International Nuclear Information System (INIS)

    Shen, Li; Chen, Jing; Li, Na; He, Pingli; Li, Zhen

    2014-01-01

    Highlights: • Tetracyclines directly reduce aurate into gold nanoparticles. • Gold nanoparticles showed characteristic plamson absorbance at 526 nm. • Quantitative detection of tetracyclines with the colorimetric assay. • Tetracyclines spiked urine samples can be detected with the assay. - Abstract: A colorimetric assay utilizing the formation of gold nanoparticles was developed to detect tetracycline antibiotics in fluidic samples. Tetracycline antibiotics showed the capability of directly reducing aurate salts into atomic gold which form gold nanoparticles spontaneously under proper conditions. The resulted gold nanoparticles showed characteristic plasmon absorbance at 526 nm, which can be visualized by naked eyes or with a spectrophotometer. UV–vis absorbance of the resulted gold nanoparticles is correlated directly with the concentrations of tetracycline antibiotics in the solution, allowing for quantitative colorimetric detection of tetracycline antibiotics. Reaction conditions, such as pH, temperature, reaction time, and ionic strength were optimized. Sensitivity of the colorimetric assay can be enhanced by the addition of gold nanoparticle seeds, a LOD as low as 20 ng mL −1 can be achieved with the help of seed particles. The colorimetric assay showed minimum interference from ethanol, methanol, urea, glucose, and other antibiotics such as sulfonamides, amino glycosides etc. Validity of the method was also evaluated on urine samples spiked with tetracycline antibiotics. The method provides a broad spectrum detection method for rapid and sensitive detection of reductive substances such as tetracycline antibiotics in liquid and biological samples

  4. Rapid colorimetric sensing of tetracycline antibiotics with in situ growth of gold nanoparticles.

    Science.gov (United States)

    Shen, Li; Chen, Jing; Li, Na; He, Pingli; Li, Zhen

    2014-08-11

    A colorimetric assay utilizing the formation of gold nanoparticles was developed to detect tetracycline antibiotics in fluidic samples. Tetracycline antibiotics showed the capability of directly reducing aurate salts into atomic gold which form gold nanoparticles spontaneously under proper conditions. The resulted gold nanoparticles showed characteristic plasmon absorbance at 526 nm, which can be visualized by naked eyes or with a spectrophotometer. UV-vis absorbance of the resulted gold nanoparticles is correlated directly with the concentrations of tetracycline antibiotics in the solution, allowing for quantitative colorimetric detection of tetracycline antibiotics. Reaction conditions, such as pH, temperature, reaction time, and ionic strength were optimized. Sensitivity of the colorimetric assay can be enhanced by the addition of gold nanoparticle seeds, a LOD as low as 20 ng mL(-1) can be achieved with the help of seed particles. The colorimetric assay showed minimum interference from ethanol, methanol, urea, glucose, and other antibiotics such as sulfonamides, amino glycosides etc. Validity of the method was also evaluated on urine samples spiked with tetracycline antibiotics. The method provides a broad spectrum detection method for rapid and sensitive detection of reductive substances such as tetracycline antibiotics in liquid and biological samples. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Rapid colorimetric sensing of tetracycline antibiotics with in situ growth of gold nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Li [Logistics School, Beijing Wuzi University, Beijing 101149 (China); Chen, Jing; Li, Na [Logistics School, Beijing Wuzi University, Beijing 101149 (China); He, Pingli [State Key Laboratory of Animal Nutrition, China Agricultural University, Beijing 100094 (China); Li, Zhen [State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100193 (China)

    2014-08-11

    Highlights: • Tetracyclines directly reduce aurate into gold nanoparticles. • Gold nanoparticles showed characteristic plamson absorbance at 526 nm. • Quantitative detection of tetracyclines with the colorimetric assay. • Tetracyclines spiked urine samples can be detected with the assay. - Abstract: A colorimetric assay utilizing the formation of gold nanoparticles was developed to detect tetracycline antibiotics in fluidic samples. Tetracycline antibiotics showed the capability of directly reducing aurate salts into atomic gold which form gold nanoparticles spontaneously under proper conditions. The resulted gold nanoparticles showed characteristic plasmon absorbance at 526 nm, which can be visualized by naked eyes or with a spectrophotometer. UV–vis absorbance of the resulted gold nanoparticles is correlated directly with the concentrations of tetracycline antibiotics in the solution, allowing for quantitative colorimetric detection of tetracycline antibiotics. Reaction conditions, such as pH, temperature, reaction time, and ionic strength were optimized. Sensitivity of the colorimetric assay can be enhanced by the addition of gold nanoparticle seeds, a LOD as low as 20 ng mL{sup −1} can be achieved with the help of seed particles. The colorimetric assay showed minimum interference from ethanol, methanol, urea, glucose, and other antibiotics such as sulfonamides, amino glycosides etc. Validity of the method was also evaluated on urine samples spiked with tetracycline antibiotics. The method provides a broad spectrum detection method for rapid and sensitive detection of reductive substances such as tetracycline antibiotics in liquid and biological samples.

  6. Rapid yet accurate measurement of mass diffusion coefficients by phase shifting interferometer

    CERN Document Server

    Guo Zhi Xiong; Komiya, A

    1999-01-01

    The technique of using a phase-shifting interferometer is applied to the study of diffusion in transparent liquid mixtures. A quick method is proposed for determining the diffusion coefficient from the measurements of the location of fringes on a grey level picture. The measurement time is very short (within 100 s) and a very small transient diffusion field can be observed and recorded accurately with a rate of 30 frames per second. The measurement can be completed using less than 0.12 cc of solutions. The influence of gravity on the measurement of the diffusion coefficient is eliminated in the present method. Results on NaCl-water diffusion systems are presented and compared with the reference data. (author)

  7. Advanced powder metallurgy aluminum alloys via rapid solidification technology, phase 2

    Science.gov (United States)

    Ray, Ranjan; Jha, Sunil C.

    1987-01-01

    Marko's rapid solidification technology was applied to processing high strength aluminum alloys. Four classes of alloys, namely, Al-Li based (class 1), 2124 type (class 2), high temperature Al-Fe-Mo (class 3), and PM X7091 type (class 4) alloy, were produced as melt-spun ribbons. The ribbons were pulverized, cold compacted, hot-degassed, and consolidated through single or double stage extrusion. The mechanical properties of all four classes of alloys were measured at room and elevated temperatures and their microstructures were investigated optically and through electron microscopy. The microstructure of class 1 Al-Li-Mg alloy was predominantly unrecrystallized due to Zr addition. Yield strengths to the order of 50 Ksi were obtained, but tensile elongation in most cases remained below 2 percent. The class 2 alloys were modified composition of 2124 aluminum alloy, through addition of 0.6 weight percent Zr and 1 weight percent Ni. Nickel addition gave rise to a fine dispersion of intermetallic particles resisting coarsening during elevated temperature exposure. The class 2 alloy showed good combination of tensile strength and ductility and retained high strength after 1000 hour exposure at 177 C. The class 3 Al-Fe-Mo alloy showed high strength and good ductility both at room and high temperatures. The yield and tensile strength of class 4 alloy exceeded those of the commercial 7075 aluminum alloy.

  8. Surface modification induced phase transformation and structure variation on the rapidly solidified recast layer of titanium

    Energy Technology Data Exchange (ETDEWEB)

    Tsai, Ming-Hung [Department of Mechanical Engineering and Graduate Institute of Mechanical and Precision Engineering, National Kaoshiung University of Applied Sciences, Kaoshiung 807, Taiwan (China); School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei 110, Taiwan (China); Haung, Chiung-Fang [School of Dental Technology, College of Oral Medicine, Taipei Medical University, Taipei 110, Taiwan (China); Division of Family and Operative Dentistry, Department of Dentistry, Taipei Medical University Hospital, Taipei 110, Taiwan (China); Research Center for Biomedical Devices and Prototyping Production, Taipei Medical University, Taipei 110, Taiwan (China); Shyu, Shih-Shiun [Department of Dentistry, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City 231, Taiwan (China); Chou, Yen-Ru [Research Center for Biomedical Devices and Prototyping Production, Taipei Medical University, Taipei 110, Taiwan (China); Graduate Institute of Biomedical Materials and Tissue Engineering, College of Oral Medicine, Taipei Medical University, Taipei 110, Taiwan (China); Research Center for Biomedical Implants and Microsurgery Devices, Taipei Medical University, Taipei 110, Taiwan (China); Lin, Ming-Hong [Department of Mechanical Engineering and Graduate Institute of Mechanical and Precision Engineering, National Kaoshiung University of Applied Sciences, Kaoshiung 807, Taiwan (China); Peng, Pei-Wen, E-mail: apon@tmu.edu.tw [School of Dental Technology, College of Oral Medicine, Taipei Medical University, Taipei 110, Taiwan (China); and others

    2015-08-15

    In this study, neodymium-doped yttrium orthovanadate (Nd:YVO{sub 4}) as a laser source with different scanning speeds was used on biomedical Ti surface. The microstructural and biological properties of laser-modified samples were investigated by means of optical microscope, electron microscope, X-ray diffraction, surface roughness instrument, contact angle and cell cytotoxicity assay. After laser modification, the rough volcano-like recast layer with micro-/nanoporous structure and wave-like recast layer with nanoporous structure were generated on the surfaces of laser-modified samples, respectively. It was also found out that, an α → (α + rutile-TiO{sub 2}) phase transition occurred on the recast layers of laser-modified samples. The Ti surface becomes hydrophilic at a high speed laser scanning. Moreover, the cell cytotoxicity assay demonstrated that laser-modified samples did not influence the cell adhesion and proliferation behaviors of osteoblast (MG-63) cell. The laser with 50 mm/s scanning speed induced formation of rough volcano-like recast layer accompanied with micro-/nanoporous structure, which can promote cell adhesion and proliferation of MG-63 cell on Ti surface. The results indicated that the laser treatment was a potential technology to enhance the biocompatibility for titanium. - Highlights: • Laser induced the formation of recast layer with micro-/nanoporous structure on Ti. • An α → (α + rutile-TiO{sub 2}) phase transition was observed within the recast layer. • The Ti surface becomes hydrophilic at a high speed laser scanning. • Laser-modified samples exhibit good biocompatibility to osteoblast (MG-63) cell.

  9. Rapid and Robust Cross-Correlation-Based Seismic Phase Identification Using an Approximate Nearest Neighbor Method

    Science.gov (United States)

    Tibi, R.; Young, C. J.; Gonzales, A.; Ballard, S.; Encarnacao, A. V.

    2016-12-01

    The matched filtering technique involving the cross-correlation of a waveform of interest with archived signals from a template library has proven to be a powerful tool for detecting events in regions with repeating seismicity. However, waveform correlation is computationally expensive, and therefore impractical for large template sets unless dedicated distributed computing hardware and software are used. In this study, we introduce an Approximate Nearest Neighbor (ANN) approach that enables the use of very large template libraries for waveform correlation without requiring a complex distributed computing system. Our method begins with a projection into a reduced dimensionality space based on correlation with a randomized subset of the full template archive. Searching for a specified number of nearest neighbors is accomplished by using randomized K-dimensional trees. We used the approach to search for matches to each of 2700 analyst-reviewed signal detections reported for May 2010 for the IMS station MKAR. The template library in this case consists of a dataset of more than 200,000 analyst-reviewed signal detections for the same station from 2002-2014 (excluding May 2010). Of these signal detections, 60% are teleseismic first P, and 15% regional phases (Pn, Pg, Sn, and Lg). The analyses performed on a standard desktop computer shows that the proposed approach performs the search of the large template libraries about 20 times faster than the standard full linear search, while achieving recall rates greater than 80%, with the recall rate increasing for higher correlation values. To decide whether to confirm a match, we use a hybrid method involving a cluster approach for queries with two or more matches, and correlation score for single matches. Of the signal detections that passed our confirmation process, 52% were teleseismic first P, and 30% were regional phases.

  10. The extracellular proteome of Rhizobium etli CE3 in exponential and stationary growth phase

    Directory of Open Access Journals (Sweden)

    Mendoza-Hernández Guillermo

    2010-10-01

    Full Text Available Abstract Background The extracellular proteome or secretome of symbiotic bacteria like Rhizobium etli is presumed to be a key element of their infection strategy and survival. Rhizobia infect the roots of leguminous plants and establish a mutually beneficial symbiosis. To find out the possible role of secreted proteins we analyzed the extracellular proteome of R. etli CE3 in the exponential and stationary growth phases in minimal medium, supplemented with succinate-ammonium. Results The extracellular proteins were obtained by phenol extraction and identified by LC-ESI MS/MS. We identified 192 and 191 proteins for the exponential and stationary phases respectively. Using the software Signal P, we predicted signal peptides for 12.95% and 35.60% of the proteins identified in the exponential and stationary phases, respectively, which could therefore be secreted by the Sec pathway. For the exponential growth phase, we found in abundance proteins like the ribosomal proteins, toxins and proteins belonging to the group "defence mechanisms". For the stationary growth phase, we found that the most abundant proteins were those with unknown function, and in many of these we identified characteristic domains of proteases and peptidases. Conclusions Our study provided the first dataset of the secretome of R. etli and its modifications, which may lead to novel insights into the adaptive response of different stages of growth. In addition, we found a high number of proteins with unknown function; these proteins could be analyzed in future research to elucidate their role in the extracellular proteome of R. etli.

  11. Rapid Population Growth and Human Carrying Capacity: Two Perspectives. World Bank Staff Working Papers No. 690 and Population and Development Series No. 15.

    Science.gov (United States)

    Mahar, Dennis J., Ed.; And Others

    Two perspectives on carrying capacity and population growth are examined. The first perspective, "Carrying Capacity and Rapid Population Growth: Definition, Cases, and Consequences" (Robert Muscat), explores the possible meanings of the idea of carrying capacity under developing country conditions, looks at historical and present-day cases of…

  12. Light-optimized growth of cyanobacterial cultures: Growth phases and productivity of biomass and secreted molecules in light-limited batch growth.

    Science.gov (United States)

    Clark, Ryan L; McGinley, Laura L; Purdy, Hugh M; Korosh, Travis C; Reed, Jennifer L; Root, Thatcher W; Pfleger, Brian F

    2018-03-27

    Cyanobacteria are photosynthetic microorganisms whose metabolism can be modified through genetic engineering for production of a wide variety of molecules directly from CO 2 , light, and nutrients. Diverse molecules have been produced in small quantities by engineered cyanobacteria to demonstrate the feasibility of photosynthetic biorefineries. Consequently, there is interest in engineering these microorganisms to increase titer and productivity to meet industrial metrics. Unfortunately, differing experimental conditions and cultivation techniques confound comparisons of strains and metabolic engineering strategies. In this work, we discuss the factors governing photoautotrophic growth and demonstrate nutritionally replete conditions in which a model cyanobacterium can be grown to stationary phase with light as the sole limiting substrate. We introduce a mathematical framework for understanding the dynamics of growth and product secretion in light-limited cyanobacterial cultures. Using this framework, we demonstrate how cyanobacterial growth in differing experimental systems can be easily scaled by the volumetric photon delivery rate using the model organisms Synechococcus sp. strain PCC7002 and Synechococcus elongatus strain UTEX2973. We use this framework to predict scaled up growth and product secretion in 1L photobioreactors of two strains of Synechococcus PCC7002 engineered for production of l-lactate or L-lysine. The analytical framework developed in this work serves as a guide for future metabolic engineering studies of cyanobacteria to allow better comparison of experiments performed in different experimental systems and to further investigate the dynamics of growth and product secretion. Copyright © 2018 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

  13. Rapid monitoring of glycerol in fermentation growth media: Facilitating crude glycerol bioprocess development.

    Science.gov (United States)

    Abad, Sergi; Pérez, Xavier; Planas, Antoni; Turon, Xavier

    2014-04-01

    Recently, the need for crude glycerol valorisation from the biodiesel industry has generated many studies for practical and economic applications. Amongst them, fermentations based on glycerol media for the production of high value metabolites are prominent applications. This has generated a need to develop analytical techniques which allow fast and simple glycerol monitoring during fermentation. The methodology should be fast and inexpensive to be adopted in research, as well as in industrial applications. In this study three different methods were analysed and compared: two common methodologies based on liquid chromatography and enzymatic kits, and the new method based on a DotBlot assay coupled with image analysis. The new methodology is faster and cheaper than the other conventional methods, with comparable performance. Good linearity, precision and accuracy were achieved in the lower range (10 or 15 g/L to depletion), the most common range of glycerol concentrations to monitor fermentations in terms of growth kinetics. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Rapid economic growth leads to boost in NO2 pollution over India, as seen from space

    Science.gov (United States)

    Hilboll, Andreas; Richter, Andreas; Burrows, John P.

    2016-04-01

    Over the past decades, the Indian economy has been growing at an exceptional pace. This growth was induced and accompanied by a strong increase of the Indian population. Consequently, traffic, electricity consumption, and industrial production have soared over the past decades, leading to a strong increase in fuel consumption and thus pollutant emissions. Nitrogen oxides (NO+NO2) are a major component of anthropogenic air pollution, playing key part in reaction cycles leading to the formation of tropospheric ozone. They are mainly emitted by the combustion of fossil fuels; other sources include production by lightning, biomass burning, and microbial activity in soils. Since the mid-1990s, space-borne measurements of tropospheric nitrogen dioxide (NO2) have been conducted by the GOME, SCIAMACHY, GOME-2, and OMI instruments. These instruments perform hyperspectral measurements of scattered and reflected sunlight. Their measurements are then analyzed using differential optical absorption spectroscopy (DOAS) to yield vertically integrated columnar trace gas abundances. Here, we will present the results of 20 years of NO2 measurements over the Indian subcontinent. After showing the spatial distribution of NO2 pollution over India, we will present time series for individual states and urban agglomerations. These time series will then be related to various indicators of economic development. Finally, we will highlight several instances where single industrial pollution sources and their development can clearly be identified from the NO2 maps and estimate their NO2 emissions.

  15. Liquid Solution Phase Epitaxial Growth of Al-doped f-SiC for LEDs

    DEFF Research Database (Denmark)

    Tang, Kai; Ma, Xiang; van der Eijk, Casper

    light quality and longer lifespan, compared to the current yellow phosphor based white LEDs. Liquid phase epitaxy technology is able to yield a high crystalline quality in terms of structural perfection owing to the fact that it is a near equilibrium process. In addition, the technological equipment...... are presented and discussed. Since operational temperature of LPE growth is much lower than that currently used in physical vapour transport (PVT) process, it is expected to save the energy consumption for SiC crystal growth....

  16. Role of Phase Composition of PEO Coatings on AA2024 for In-Situ LDH Growth

    Directory of Open Access Journals (Sweden)

    Maria Serdechnova

    2017-11-01

    Full Text Available Plasma electrolytic oxidation (PEO is an environmentally friendly anodizing technique leading to the formation of a ceramic-like coatings under high-voltage discharges. Layered double hydroxides (LDHs were grown directly on γ, α, and amorphous Al2O3 powders, respectively, in order to investigate the phase responsible for in-situ LDH growth on PEO coating. Furthermore, it is shown that LDH growth is limited by the high tortuosity of the PEO layer and the accessibility of Al ( OH 4 − anions from the substrate covered with thin amorphous aluminum oxide, through the pores.

  17. Analysis of the effect on growth kinetics of gamma prima phase in Inconel 713C alloys

    International Nuclear Information System (INIS)

    Thorp, S.I.; Versaci, R.A.; Ges, A.; Palacio, H.A.

    1993-01-01

    This work shows the analysis of the effect on growth kinetics of gamma prima phase in Inconel 713C alloy of two thermic treatments. In this study, SEM are used and the results are analyzed by means of the theory developed by Lifshitz, Slyozov and Wagner (LSW theory). The findings have revealed that with such theory it is not possible to determine if the process of growth is controlled either through diffusion or through diffusion in the interface as to the time employed in the experiment (2600 hours); the time required is approximately 10000 hours. (Author)

  18. Matching time and spatial scales of rapid solidification: dynamic TEM experiments coupled to CALPHAD-informed phase-field simulations

    Science.gov (United States)

    Perron, Aurelien; Roehling, John D.; Turchi, Patrice E. A.; Fattebert, Jean-Luc; McKeown, Joseph T.

    2018-01-01

    A combination of dynamic transmission electron microscopy (DTEM) experiments and CALPHAD-informed phase-field simulations was used to study rapid solidification in Cu-Ni thin-film alloys. Experiments—conducted in the DTEM—consisted of in situ laser melting and determination of the solidification kinetics by monitoring the solid-liquid interface and the overall microstructure evolution (time-resolved measurements) during the solidification process. Modelling of the Cu-Ni alloy microstructure evolution was based on a phase-field model that included realistic Gibbs energies and diffusion coefficients from the CALPHAD framework (thermodynamic and mobility databases). DTEM and post mortem experiments highlighted the formation of microsegregation-free columnar grains with interface velocities varying from ˜0.1 to ˜0.6 m s-1. After an ‘incubation’ time, the velocity of the planar solid-liquid interface accelerated until solidification was complete. In addition, a decrease of the temperature gradient induced a decrease in the interface velocity. The modelling strategy permitted the simulation (in 1D and 2D) of the solidification process from the initially diffusion-controlled to the nearly partitionless regimes. Finally, results of DTEM experiments and phase-field simulations (grain morphology, solute distribution, and solid-liquid interface velocity) were consistent at similar time (μs) and spatial scales (μm).

  19. Suppressed phase variations in a high amplitude rapidly oscillating Ap star pulsating in a distorted quadrupole mode

    Science.gov (United States)

    Holdsworth, Daniel L.; Saio, H.; Bowman, D. M.; Kurtz, D. W.; Sefako, R. R.; Joyce, M.; Lambert, T.; Smalley, B.

    2018-05-01

    We present the results of a multisite photometric observing campaign on the rapidly oscillating Ap (roAp) star 2MASS 16400299-0737293 (J1640; V = 12.7). We analyse photometric B data to show the star pulsates at a frequency of 151.93 d-1 (1758.45 μHz; P = 9.5 min) with a peak-to-peak amplitude of 20.68 mmag, making it one of the highest amplitude roAp stars. No further pulsation modes are detected. The stellar rotation period is measured at 3.674 7 ± 0.000 5 d, and we show that rotational modulation due to spots is in antiphase between broad-band and B observations. Analysis and modelling of the pulsation reveals this star to be pulsating in a distorted quadrupole mode, but with a strong spherically symmetric component. The pulsational phase variation in this star is suppressed, leading to the conclusion that the contribution of ℓ > 2 components dictate the shape of phase variations in roAp stars that pulsate in quadrupole modes. This is only the fourth time such a strong pulsation phase suppression has been observed, leading us to question the mechanisms at work in these stars. We classify J1640 as an A7 Vp SrEu(Cr) star through analysis of classification resolution spectra.

  20. Role of microorganism growth phase in the accumulation and characteristics of biomacromolecules (BMM) in a membrane bioreactor

    DEFF Research Database (Denmark)

    Zhou, Zhongbo; Meng, Fangang; Liang, Shuang

    2012-01-01

    The objective of this study was to highlight the significance of microorganism growth on the production of biomacromolecules (BMM) in a membrane bioreactor (MBR). During the MBR operation, both polysaccharides and proteins in the sludge supernatant were found to increase steadily in exponential...... growth phase (EGP) due to higher organic loading rates and microbial primary metabolism. Subsequently, both increased continuously and then decreased sharply in the following deceleration growth phase (DGP). Finally, the BMM maintained a low and steady level as the sludge reached stationary growth phase...

  1. GPU-accelerated 3D phase-field simulations of dendrite competitive growth during directional solidification of binary alloy

    International Nuclear Information System (INIS)

    Sakane, S; Takaki, T; Ohno, M; Shimokawabe, T; Aoki, T

    2015-01-01

    Phase-field method has emerged as the most powerful numerical scheme to simulate dendrite growth. However, most phase-field simulations of dendrite growth performed so far are limited to two-dimension or single dendrite in three-dimension because of the large computational cost involved. To express actual solidification microstructures, multiple dendrites with different preferred growth directions should be computed at the same time. In this study, in order to enable large-scale phase-field dendrite growth simulations, we developed a phase-field code using multiple graphics processing units in which a quantitative phase-field method for binary alloy solidification and moving frame algorithm for directional solidification were employed. First, we performed strong and weak scaling tests for the developed parallel code. Then, dendrite competitive growth simulations in three-dimensional binary alloy bicrystal were performed and the dendrite interactions in three-dimensional space were investigated. (paper)

  2. Using Bayesian Belief Network (BBN) modelling for Rapid Source Term Prediction. RASTEP Phase 1

    International Nuclear Information System (INIS)

    Knochenhauer, M.; Swaling, V.H.; Alfheim, P.

    2012-09-01

    The project is connected to the development of RASTEP, a computerized source term prediction tool aimed at providing a basis for improving off-site emergency management. RASTEP uses Bayesian belief networks (BBN) to model severe accident progression in a nuclear power plant in combination with pre-calculated source terms (i.e., amount, timing, and pathway of released radio-nuclides). The output is a set of possible source terms with associated probabilities. In the NKS project, a number of complex issues associated with the integration of probabilistic and deterministic analyses are addressed. This includes issues related to the method for estimating source terms, signal validation, and sensitivity analysis. One major task within Phase 1 of the project addressed the problem of how to make the source term module flexible enough to give reliable and valid output throughout the accident scenario. Of the alternatives evaluated, it is recommended that RASTEP is connected to a fast running source term prediction code, e.g., MARS, with a possibility of updating source terms based on real-time observations. (Author)

  3. The hydrodynamics of segmented two-phase flow in a circular tube with rapidly dissolving drops.

    Science.gov (United States)

    Leary, Thomas F; Ramachandran, Arun

    2017-05-03

    This article discusses boundary integral simulations of dissolving drops flowing through a cylindrical tube for large aspect ratio drops. The dynamics of drop dissolution is determined by three dimensionless parameters: λ, the viscosity of the drop fluid relative to the suspending fluid; Ca, the capillary number defining the ratio of the hydrodynamic force to the interfacial tension force; and k, a dissolution constant based on the velocity of dissolution. For a single dissolving drop, the velocity in the upstream region is greater than the downstream region, and for sufficiently large k, the downstream velocity can be completely reversed, particularly at low Ca. The upstream end of the drop travels faster and experiences greater deformation than the downstream end. The film thickness, δ, between the drop and the tube wall is governed by a delicate balance between dissolution and changes in the outer fluid velocity resulting from a fixed pressure drop across the tube and mass continuity. Therefore, δ, and consequently, the drop average velocity, can increase, decrease or be relatively invariant in time. For two drops flowing in succession, while low Ca drops maintain a nearly constant separation distance during dissolution, at sufficiently large Ca, for all values of k, dissolution increases the separation distance between drops. Under these conditions, the liquid segments between two adjacent drops can no longer be considered as constant volume stirred tanks. These results will guide the choices of geometry and operating parameters that will facilitate the characterization of fast gas-liquid reactions via two-phase segmented flows.

  4. Using Bayesian Belief Network (BBN) modelling for Rapid Source Term Prediction. RASTEP Phase 1

    Energy Technology Data Exchange (ETDEWEB)

    Knochenhauer, M.; Swaling, V.H.; Alfheim, P. [Scandpower AB, Sundbyberg (Sweden)

    2012-09-15

    The project is connected to the development of RASTEP, a computerized source term prediction tool aimed at providing a basis for improving off-site emergency management. RASTEP uses Bayesian belief networks (BBN) to model severe accident progression in a nuclear power plant in combination with pre-calculated source terms (i.e., amount, timing, and pathway of released radio-nuclides). The output is a set of possible source terms with associated probabilities. In the NKS project, a number of complex issues associated with the integration of probabilistic and deterministic analyses are addressed. This includes issues related to the method for estimating source terms, signal validation, and sensitivity analysis. One major task within Phase 1 of the project addressed the problem of how to make the source term module flexible enough to give reliable and valid output throughout the accident scenario. Of the alternatives evaluated, it is recommended that RASTEP is connected to a fast running source term prediction code, e.g., MARS, with a possibility of updating source terms based on real-time observations. (Author)

  5. Rapid Start-up and Loading of an Attached Growth, Simultaneous Nitrification/Denitrification Membrane Aerated Bioreactor

    Science.gov (United States)

    Meyer, Caitlin E.; Pensinger, Stuart; Pickering, Karen D.; Barta, Daniel; Shull, Sarah A.; Vega, Letticia M.; Christenson, Dylan; Jackson, W. Andrew

    2015-01-01

    Membrane aerated bioreactors (MABR) are attached-growth biological systems used for simultaneous nitrification and denitrification to reclaim water from waste. This design is an innovative approach to common terrestrial wastewater treatments for nitrogen and carbon removal and implementing a biologically-based water treatment system for long-duration human exploration is an attractive, low energy alternative to physiochemical processes. Two obstacles to implementing such a system are (1) the "start-up" duration from inoculation to steady-state operations and (2) the amount of surface area needed for the biological activity to occur. The Advanced Water Recovery Systems (AWRS) team at JSC explored these two issues through two tests; a rapid inoculation study and a wastewater loading study. Results from these tests demonstrate that the duration from inoculation to steady state can be reduced to under two weeks, and that despite low ammonium removal rates, the MABRs are oversized.

  6. A rapid, reliable method of evaluating growth and viability of intraerythrocytic protozoan hemoparasites using fluorescence flow cytometry.

    Science.gov (United States)

    Davis, W C; Wyatt, C R; Hamilton, M J; Goff, W L

    1992-01-01

    Fluorescence flow cytometry was employed to assess the potential of a vital dye, hydroethidine, for use in the detection and monitoring of the viability of hemoparasites in infected erythrocytes, using Babesia bovis as a model parasite. The studies demonstrated that hydroethidine is taken up by B. bovis and metabolically converted to the DNA binding fluorochrome, ethidium. Following uptake of the dye, erythrocytes containing viable parasites were readily distinguished and quantitated. Timed studies with the parasiticidal drug, Ganaseg, showed that it is possible to use the fluorochrome assay to monitor the effects of the drug on the rate of replication and viability of B. bovis in culture. The assay provides a rapid method for evaluation of the in vitro effect of drugs on hemoparasites and for analysis of the effect of various components of the immune response, such as lymphokines, monocyte products, antibodies, and effector cells (T, NK, LAK, ADCC) on the growth and viability of intraerythrocytic parasites.

  7. A rapid, reliable method of evaluating growth and viability of intraerythrocytic protozoan hemoparasites using fluorescence flow cytometry

    Directory of Open Access Journals (Sweden)

    W. C. Davis

    1992-01-01

    Full Text Available Fluorescence flow cytometry was employed to assess the potential of a vital dye, hydroethiedine, for use in the detection and monitoring of the viability of hemoparasites in infected erythrocytes, using Babesia bovis as a model parasite. The studies demonstrated that hydroethidine is taken up by B. bovis and metabolically converted to the DNA binding fluorochrone, ethidium. Following uptake of the dye, erythrocytes contamine viable parasites were readily distinguished and quantitated. Timed studies with the parasiticidal drug, Ganaseg, showed that it is possible to use the fluorochrome assay to monitor the effects of the drug on the rate of replication and viability of B. bovis in culture. The assay provides a rapid method for evaluation of the in vitro effect of drugs on hemoparasites and for analysis of the effect of various components of the immune response, such as lymphokines, monocyte products, antibodies, and effector cells (T, NK, LAK, ADCC on the growth and viability of intraerythrocytic parasites.

  8. Rapid T1 quantification based on 3D phase sensitive inversion recovery

    Directory of Open Access Journals (Sweden)

    Warntjes Marcel JB

    2010-08-01

    Full Text Available Abstract Background In Contrast Enhanced Magnetic Resonance Imaging fibrotic myocardium can be distinguished from healthy tissue using the difference in the longitudinal T1 relaxation after administration of Gadolinium, the so-called Late Gd Enhancement. The purpose of this work was to measure the myocardial absolute T1 post-Gd from a single breath-hold 3D Phase Sensitivity Inversion Recovery sequence (PSIR. Equations were derived to take the acquisition and saturation effects on the magnetization into account. Methods The accuracy of the method was investigated on phantoms and using simulations. The method was applied to a group of patients with suspected myocardial infarction where the absolute difference in relaxation of healthy and fibrotic myocardium was measured at about 15 minutes post-contrast. The evolution of the absolute R1 relaxation rate (1/T1 over time after contrast injection was followed for one patient and compared to T1 mapping using Look-Locker. Based on the T1 maps synthetic LGE images were reconstructed and compared to the conventional LGE images. Results The fitting algorithm is robust against variation in acquisition flip angle, the inversion delay time and cardiac arrhythmia. The observed relaxation rate of the myocardium is 1.2 s-1, increasing to 6 - 7 s-1 after contrast injection and decreasing to 2 - 2.5 s-1 for healthy myocardium and to 3.5 - 4 s-1 for fibrotic myocardium. Synthesized images based on the T1 maps correspond very well to actual LGE images. Conclusions The method provides a robust quantification of post-Gd T1 relaxation for a complete cardiac volume within a single breath-hold.

  9. Rapid growth of amorphous carbon films on the inner surface of micron-thick and hollow-core fibers

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Longfei [Fujian Key Laboratory for Plasma and Magnetic Resonance, Department of Electric Science, School of Physics and Mechanical and Electrical Engineering, Xiamen University, Xiamen, Fujian 361005 (China); School of Physics and Materials Engineering, Dalian Nationalities University, Dalian 116600 (China); School of Science, Changchun University of Science and Technology, Changchun, Jilin 130022 (China); Liu, Dongping, E-mail: Dongping.liu@dlnu.edu.cn [Fujian Key Laboratory for Plasma and Magnetic Resonance, Department of Electric Science, School of Physics and Mechanical and Electrical Engineering, Xiamen University, Xiamen, Fujian 361005 (China); School of Physics and Materials Engineering, Dalian Nationalities University, Dalian 116600 (China); School of Science, Changchun University of Science and Technology, Changchun, Jilin 130022 (China); Zhou, Xinwei [Department of Mechanical Engineering, Zhejiang University, Zhejiang 310007 (China); Song, Ying [School of Physics and Materials Engineering, Dalian Nationalities University, Dalian 116600 (China); School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116023 (China); Ni, Weiyuan [School of Physics and Materials Engineering, Dalian Nationalities University, Dalian 116600 (China); School of Science, Changchun University of Science and Technology, Changchun, Jilin 130022 (China); Niu, Jinhai; Fan, Hongyu [School of Physics and Materials Engineering, Dalian Nationalities University, Dalian 116600 (China)

    2013-10-01

    Ultrathick (> 25 μm) carbon films were obtained on the inner surface of hollow and micron-thick quartz fibers by confining CH{sub 4}/He or C{sub 2}H{sub 2}/He microplasmas in their hollow cores. The resulting carbon films were studied by using scanning electron microscopy and energy-dispersive X-ray spectroscopy. The microplasma-enhanced chemical vapor deposition (CVD) technique resulted in the uniform growth of amorphous carbon films on the inner surface of very long (> 1 m) hollow-core fibers. Film deposition is performed by using microplasmas at atmospheric pressure and at 50 Pa. The carbon films obtained with the latter show the smooth inner surfaces and the well continuity across the film/optical fiber. Low-pressure CH{sub 4}/He and C{sub 2}H{sub 2}/He microplasmas can lead to a rapid growth (∼ 2.00 μm/min) of carbon films with their thickness of > 25 μm. The optical emission measurements show that various hydrocarbon species were formed in these depositing microplasmas due to the collisions between CH{sub 4}/C{sub 2}H{sub 2} molecules and energetic species. The microplasma-enhanced CVD technique running without the complicated fabrication processes shows its potentials for rapidly depositing the overlong carbon tubes with their inner diameters of tens of microns. - Highlights: • The microplasma device is applied for coating deposition inside hollow-core fibers. • The microplasma device results in > 25 μm-thick carbon films. • The microplasma device is simple for deposition of ultralong carbon tubes.

  10. Growth of second phase particles in a copper--beryllium alloy. Final technical report

    International Nuclear Information System (INIS)

    Bunch, R.; Wells, R.; Mukherjee, A.K.

    1977-01-01

    Growth of second phase particles from a solid solution of copper-beryllium was studied to determine this alloy's suitability for acoustic emission testing. Optical and Scanning Electron microscopes were used to study the microstructure. Micro and macro hardness tests were also performed. A hardness curve for aging at 550 0 F was determined. Microscopic examination revealed the presence of large inclusions which make this alloy unsuitable for the acoustic tests envisioned

  11. Growth potential of exponential- and stationary-phase Salmonella Typhimurium during sausage fermentation

    DEFF Research Database (Denmark)

    Birk, Tina; Henriksen, Sidsel; Müller, K.

    2016-01-01

    - and stationary-phase Salmonella Typhimurium (DT12 and DTU292) during freezing at − 18 °C and their subsequent growth potential during 72 h sausage fermentation at 25 °C. After 0, 7 and > 35 d of frozen storage, sausage batters were prepared with NaCl (3%) and NaNO2 (0, 100 ppm) and fermented with and without...

  12. Abnormal grain growth in Eurofer-97 steel in the ferrite phase field

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, V.B. [Lorena School of Engineering, University of Sao Paulo, Lorena, SP, 12602-810 (Brazil); Sandim, H.R.Z., E-mail: hsandim@demar.eel.usp.br [Lorena School of Engineering, University of Sao Paulo, Lorena, SP, 12602-810 (Brazil); Raabe, D. [Max-Planck-Institut für Eisenforschung, Düsseldorf, D-40237 (Germany)

    2017-03-15

    Reduced-activation ferritic-martensitic (RAFM) Eurofer-97 steel is a candidate material for structural applications in future fusion reactors. Depending on the amount of prior cold rolling strain and annealing temperature, important solid-state softening reactions such as recovery, recrystallization, and grain growth occur. Eurofer-97 steel was cold rolled up to 70, 80 and 90% reductions in thickness and annealed in the ferrite phase field (below ≈ 800 °C). Changes in microstructure, micro-, and mesotexture were followed by orientation mappings provided by electron backscatter diffraction (EBSD). Eurofer-97 steel undergoes abnormal grain growth above 650 °C and this solid-state reaction seems to be closely related to the high mobility of a few special grain boundaries that overcome pinning effects caused by fine particles. This solid-state reaction promotes important changes in the microstructure and microtexture of this steel. Abnormal grain growth kinetics for each condition was determined by means of quantitative metallography. - Highlights: • Abnormal grain growth (AGG) occurs in Eurofer-97 steel deformed to several strains. • Kinetics of abnormal grain growth has been determined at 750 and 800 °C. • Significant changes in crystallographic texture take place during AGG. • Grain boundaries with misorientations above 45° may explain abnormal grain growth. • Local microstructural instabilities (coarsening of M23C6 carbides) also explain AGG.

  13. Identification of growth phases and influencing factors in cultivations with AGE1.HN cells using set-based methods.

    Directory of Open Access Journals (Sweden)

    Steffen Borchers

    Full Text Available Production of bio-pharmaceuticals in cell culture, such as mammalian cells, is challenging. Mathematical models can provide support to the analysis, optimization, and the operation of production processes. In particular, unstructured models are suited for these purposes, since they can be tailored to particular process conditions. To this end, growth phases and the most relevant factors influencing cell growth and product formation have to be identified. Due to noisy and erroneous experimental data, unknown kinetic parameters, and the large number of combinations of influencing factors, currently there are only limited structured approaches to tackle these issues. We outline a structured set-based approach to identify different growth phases and the factors influencing cell growth and metabolism. To this end, measurement uncertainties are taken explicitly into account to bound the time-dependent specific growth rate based on the observed increase of the cell concentration. Based on the bounds on the specific growth rate, we can identify qualitatively different growth phases and (in-validate hypotheses on the factors influencing cell growth and metabolism. We apply the approach to a mammalian suspension cell line (AGE1.HN. We show that growth in batch culture can be divided into two main growth phases. The initial phase is characterized by exponential growth dynamics, which can be described consistently by a relatively simple unstructured and segregated model. The subsequent phase is characterized by a decrease in the specific growth rate, which, as shown, results from substrate limitation and the pH of the medium. An extended model is provided which describes the observed dynamics of cell growth and main metabolites, and the corresponding kinetic parameters as well as their confidence intervals are estimated. The study is complemented by an uncertainty and outlier analysis. Overall, we demonstrate utility of set-based methods for analyzing cell

  14. Identification of growth phases and influencing factors in cultivations with AGE1.HN cells using set-based methods.

    Science.gov (United States)

    Borchers, Steffen; Freund, Susann; Rath, Alexander; Streif, Stefan; Reichl, Udo; Findeisen, Rolf

    2013-01-01

    Production of bio-pharmaceuticals in cell culture, such as mammalian cells, is challenging. Mathematical models can provide support to the analysis, optimization, and the operation of production processes. In particular, unstructured models are suited for these purposes, since they can be tailored to particular process conditions. To this end, growth phases and the most relevant factors influencing cell growth and product formation have to be identified. Due to noisy and erroneous experimental data, unknown kinetic parameters, and the large number of combinations of influencing factors, currently there are only limited structured approaches to tackle these issues. We outline a structured set-based approach to identify different growth phases and the factors influencing cell growth and metabolism. To this end, measurement uncertainties are taken explicitly into account to bound the time-dependent specific growth rate based on the observed increase of the cell concentration. Based on the bounds on the specific growth rate, we can identify qualitatively different growth phases and (in-)validate hypotheses on the factors influencing cell growth and metabolism. We apply the approach to a mammalian suspension cell line (AGE1.HN). We show that growth in batch culture can be divided into two main growth phases. The initial phase is characterized by exponential growth dynamics, which can be described consistently by a relatively simple unstructured and segregated model. The subsequent phase is characterized by a decrease in the specific growth rate, which, as shown, results from substrate limitation and the pH of the medium. An extended model is provided which describes the observed dynamics of cell growth and main metabolites, and the corresponding kinetic parameters as well as their confidence intervals are estimated. The study is complemented by an uncertainty and outlier analysis. Overall, we demonstrate utility of set-based methods for analyzing cell growth and

  15. Rapid solid-phase radioimmunoassay for detection of equine infectious anemia viral antigen and antibodies: parameters involved in standardization

    International Nuclear Information System (INIS)

    Horenstein, A.L.; Feinstein, R.E.

    1985-01-01

    Solid-phase radioimmunoassays (SPRIA) are described for the detection of equine infectious anemia (EIA) viral antigen and antibodies. Protein-antigen P29 currently used in the agar-gel immunodiffusion (AGID) test was used as antigen in the SPRIA. The specificity of the reaction was assessed by inhibition with the antigen. The reaction of immune serum against EIA-virus antigen adsorbed to the wells, was completely inhibited by the antigen in solution. This property was applied in an indirect competitive SPRIA for the detection of viral protein P29. The detection threshold of the SPRIA for EIA virus protein was about 5 ng and about 1 ng of antibody can be detected. The assay is rapid, specific and sensitive and allows the testing of multiple serum samples with the advantage of employing a single secondary labelled antibody. (orig.)

  16. Rapid analysis of malathion in blood using head space-solid phase microextraction and selected ion monitoring.

    Science.gov (United States)

    Namera, A; Yashiki, M; Nagasawa, N; Iwasaki, Y; Kojima, T

    1997-08-04

    A simple and rapid method for analysis of malathion in blood was developed using head space-solid phase microextraction (HS-SPME) and gas chromatography mass spectrometry/ electron impact ionization-selected ion monitoring (GC-MS/EI-SIM). A vial containing a blood sample, ammonium sulphate, sulphuric acid and fenitrothion as an internal standard, was heated at 90 degrees C for 15 min. The extraction fiber of the SPME was exposed for 5 min in the head space of the vial. The compounds absorbed on the fiber were detached by exposing the fibre in the injection port of GC-MS. A straight calibration curve was obtained between malathion concentrations of 2.5 to 50.0 micrograms g-1 in blood. No interfering substances were found, and the time for analysis was 40 min for one sample.

  17. Glacier Instability, Rapid Glacier Lake Growth and Related Hazards at Belvedere Glacier, Macugnaga, Italy

    Science.gov (United States)

    Huggel, C.; Kaeaeb, A.; Haeberli, W.; Mortara, G.; Chiarle, M.; Epifani, F.

    2002-12-01

    Starting in summer 2000, Belvedere Glacier, near Macugnaga, Italian Alps, developed an extraordinary change in flow, geometry and surface appearance. A surge-type flow acceleration started in the lower parts of the Monte-Rosa east face, leading to strong crevassing and deformation of Belvedere Glacier, accompanied by bulging of its orographic right margin. In September 2001, a small supraglacial lake developed on the glacier. High water pressure and accelerated movement lasted into winter 2001/2002. The ice, in places, started to override moraines from the Little Ice Age. In late spring and early summer 2002, the supraglacial lake grew at extraordinary rates reaching a maximum area of more than 150'000 m2 by end of June. The evolution of such a large supraglacial lake, a rather unique feature in the Alps, was probably enabled by changes in the subglacial drainage system in the course of the surge-like developments with high water pressure in the glacier. At the end of June, an enhanced growth of the lake level with a rise of about 1 m per day was observed such that the supraglacial lake became a urgent hazard problem for the community of Macugnaga. Emergency measures had to be taken by the Italian Civil Protection. The authors thereby acted as the official expert advisers. Temporal evacuations were ordered and a permanent monitoring and alarm system was installed. Pumps with a maximum output of 1 m3/s were brought to the lake. Bathymetric studies yielded a maximum lake depth of 55 m and a volume of 3.3 millions of cubic meters of water. Aerial photography of 1995, 1999, September 2001 and October 2001 was used to calculate ice flow velocities and changes in surface altitude. Compared to the period of 1995 to 1999, the flow accelerated by about five times in 2001 (max. speeds up to 200 m/yr). Surface uplift measured was about 10-15 m/yr. The results of the photogrammetric studies were used to evaluate different possible lake-outburst scenarios, in particular

  18. Competitive grain growth in directional solidification investigated by phase field simulation

    International Nuclear Information System (INIS)

    Li Junjie; Wang Zhijun; Wang Jincheng; Yang Yujuan

    2012-01-01

    During directional solidification, the competitive dendritic growth between various oriented grains is a key factor to obtain desirable texture. In order to understand the mechanism of competitive dendritic growth, the phase field method was adopted to simulate the microstructure evolution of bicrystal samples. The simulation has well reproduced the whole competitive growth process for both diverging and converging dendrites. In converging case, besides the block of the unfavorably oriented dendrite by the favorably oriented one, the unfavorably oriented dendrite is also able to overgrow the favorable one under the condition of relatively low pulling velocity. This unusual overgrowth is dictated by the solute interaction of the converging dendrite tips. In diverging case, it was found that the grain boundary can be either inclined or parallel to the favorably oriented grain depending on the disposition of two grains.

  19. Transcriptional Characterization of Salmonella TAl00 in Growth and Stationary Phase: Mutagenesis of MX in Both Types of Cells

    Science.gov (United States)

    The Salmonella (Ames) mutagenicity assay can be performed using cells that are in different growth phases. Thus, the plate-incorporation assay involves plating stationary-phase cells with the mutagen, after which the cells undergo a brief lag phase and, consequently, are exposed ...

  20. DNA microarray-based solid-phase RT-PCR for rapid detection and identification of influenza virus type A and subtypes H5 and H7

    DEFF Research Database (Denmark)

    Yi, Sun; Dhumpa, Raghuram; Bang, Dang Duong

    2011-01-01

    of RNA extract in the liquid phase with sequence-specific nested PCR on the solid phase. A simple ultraviolet cross-linking method was used to immobilize the DNA probes over an unmodified glass surface, which makes solid-phase PCR a convenient possibility for AIV screening. The testing of 33 avian fecal....... In this article, a DNA microarray-based solid-phase polymerase chain reaction (PCR) approach has been developed for rapid detection of influenza virus type A and for simultaneous identification of pathogenic virus subtypes H5 and H7. This solid-phase RT-PCR method combined reverse-transcription amplification...

  1. Impact of metabolism and growth phase on the hydrogen isotopic composition of microbial fatty acids

    Science.gov (United States)

    Heinzelmann, Sandra M.; Villanueva, Laura; Sinke-Schoen, Danielle; Sinninghe Damsté, Jaap S.; Schouten, Stefan; van der Meer, Marcel T. J.

    2015-01-01

    Microorganisms are involved in all elemental cycles and therefore it is important to study their metabolism in the natural environment. A recent technique to investigate this is the hydrogen isotopic composition of microbial fatty acids, i.e., heterotrophic microorganisms produce fatty acids enriched in deuterium (D) while photoautotrophic and chemoautotrophic microorganisms produce fatty acids depleted in D compared to the water in the culture medium (growth water). However, the impact of factors other than metabolism have not been investigated. Here, we evaluate the impact of growth phase compared to metabolism on the hydrogen isotopic composition of fatty acids of different environmentally relevant microorganisms with heterotrophic, photoautotrophic and chemoautotrophic metabolisms. Fatty acids produced by heterotrophs are enriched in D compared to growth water with εlipid/water between 82 and 359‰ when grown on glucose or acetate, respectively. Photoautotrophs (εlipid/water between −149 and −264‰) and chemoautotrophs (εlipid/water between −217 and −275‰) produce fatty acids depleted in D. Fatty acids become, in general, enriched by between 4 and 46‰ with growth phase which is minor compared to the influence of metabolisms. Therefore, the D/H ratio of fatty acids is a promising tool to investigate community metabolisms in nature. PMID:26005437

  2. Mutations Enhancing Amino Acid Catabolism Confer a Growth Advantage in Stationary Phase

    Science.gov (United States)

    Zinser, Erik R.; Kolter, Roberto

    1999-01-01

    Starved cultures of Escherichia coli undergo successive rounds of population takeovers by mutants of increasing fitness. These mutants express the growth advantage in stationary phase (GASP) phenotype. Previous work identified the rpoS819 allele as a GASP mutation allowing cells to take over stationary-phase cultures after growth in rich media (M. M. Zambrano, D. A. Siegele, M. A. Almirón, A. Tormo, and R. Kolter, Science 259:1757–1760, 1993). Here we have identified three new GASP loci from an aged rpoS819 strain: sgaA, sgaB, and sgaC. Each locus is capable of conferring GASP on the rpoS819 parent, and they can provide successively higher fitnesses for the bacteria in the starved cultures. All four GASP mutations isolated thus far allow for faster growth on both individual and mixtures of amino acids. Each mutation confers a growth advantage on a different subset of amino acids, and these mutations act in concert to increase the overall catabolic capacity of the cell. We present a model whereby this enhanced ability to catabolize amino acids is responsible for the fitness gain during carbon starvation, as it may allow GASP mutants to outcompete the parental cells when growing on the amino acids released by dying cells. PMID:10482523

  3. Rapid analysis of water- and fat-soluble vitamins by electrokinetic chromatography with polymeric micelle as pseudostationary phase.

    Science.gov (United States)

    Ni, Xinjiong; Xing, Xiaoping; Cao, Yuhua; Cao, Guangqun

    2014-11-28

    A novel polymeric micelle, formed by random copolymer poly (stearyl methacrylate-co-methacrylic acid) (P(SMA-co-MAA)) has been used as pseudostationary phase (PSP) in electrokinetic chromatography (EKC) for simultaneous and rapid determination of 11 kinds of water- and fat-soluble vitamins in this work. The running buffer consisting of 1% (w/v) P(SMA-co-MAA), 10% (v/v) 1-butanol, 20% (v/v) acetonitrile, and 30 mM Palitzsch buffer solution (pH 9.2) was applied to improve the selectivity and efficiency, as well as to shorten analysis time. 1-Butanol and acetonitrile as the organic solvent modifiers played the most important roles for rapid separation of these vitamins. The effects of organic solvents on microstructure of the polymeric micelle were investigated. The organic solvents swell the polymeric micelle by three folds, lower down the surface charge density and enhance the microenviromental polarity of the polymeric micelle. The 11 kinds of water- and fat-soluble vitamins could be baseline separated within 13 min. The method was applied to determine water- and fat-soluble vitamins in commercial vitamin sample; the recoveries were between 93% and 111% with the relative standard derivations (RSDs) less than 5%. The determination results matched the label claim. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Minimization of diauxic growth lag-phase for high-efficiency biogas production.

    Science.gov (United States)

    Kim, Min Jee; Kim, Sang Hun

    2017-02-01

    The objective of this study was to develop a minimization method of a diauxic growth lag-phase for the biogas production from agricultural by-products (ABPs). Specifically, the effects of proximate composition on the biogas production and degradation rates of the ABPs were investigated, and a new method based on proximate composition combinations was developed to minimize the diauxic growth lag-phase. Experiments were performed using biogas potential tests at a substrate loading of 2.5 g VS/L and feed to microorganism ratio (F/M) of 0.5 under the mesophilic condition. The ABPs were classified based on proximate composition (carbohydrate, protein, and fat etc.). The biogas production patterns, lag phase, and times taken for 90% biogas production (T90) were used for the evaluation of the biogas production with biochemical methane potential (BMP) test. The high- or medium-carbohydrate and low-fat ABPs (cheese whey, cabbage, and skim milk) showed a single step digestion process and low-carbohydrate and high-fat ABPs (bean curd and perilla seed) showed a two-step digestion process. The mixture of high-fat ABPs and high-carbohydrate ABPs reduced the lag-phase and increased the biogas yield more than that from single ABP by 35-46%. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Rapid structural and compositional change in an old-growth subtropical forest: using plant traits to identify probable drivers.

    Science.gov (United States)

    Malizia, Agustina; Easdale, Tomás A; Grau, H Ricardo

    2013-01-01

    Recent studies have shown directional changes in old-growth tropical forests, but changes are complex and diverse, and their drivers unclear. Here, we report rapid net structural and compositional changes in an old-growth subtropical forest and we assess the functional nature of these changes to test hypothetical drivers including recovery from past disturbances, reduction in ungulate browsing, CO2 fertilization, and increases in rainfall and temperature. The study relies on 15 years of demographic monitoring within 8 ha of subtropical montane forest in Argentina. Between 1992 and 2007, stem density markedly increased by 50% (12 stems ha(-1) y(-1)) and basal area by 6% (0.13 m(2) ha(-1) y(-1)). Increased stem density resulted from enhanced recruitment of understory treelets (Piper tucumanum, Eugenia uniflora, Allophylus edulis) into small size classes. Among 27 common tree species, net population growth was negatively correlated with maximum tree size and longevity, and positively correlated with leaf size and leaf nutrient content, especially so when initial population size was controlled for. Changes were inconsistent with predictions derived from past disturbances (no increase in shade-tolerant or long-lived late-succesional species), rainfall or temperature increase (no increase in evergreen or deciduous species, respectively). However, the increase in nutrient-rich soft-leaved species was consistent with exclusion of large herbivores two decades before monitoring started; and CO2 fertilization could help explain the disproportionate increase in small stems. Reductions in populations of large vertebrates have been observed in many otherwise undisturbed tropical forests, and our results suggest they can have important structural and functional repercussions in these forests.

  6. Rapid Determination of Bile Acids in Bile from Various Mammals by Reversed-Phase Ultra-Fast Liquid Chromatography.

    Science.gov (United States)

    Si, Gu Leng Ri; Yao, Peng; Shi, Luwen

    2015-08-01

    A valid and efficient reversed-phase ultra-fast liquid chromatography method was developed for the simultaneous determination of 13 bile acids in the bile of three mammal species, including rat, pig and human gallstone patients. Chromatographic separation was performed with a Shim-pack XR-ODS column, and the mobile phase consisted of acetonitrile and potassium phosphate buffer (pH 2.6) at a flow rate of 0.5 mL min(-1). The linear detection range of most bile acids ranged from 2 to 600 ng µL(-1) with a good correlation coefficient (>0.9995). The precision of each bile acid was bile acids were separated in 15 min with satisfactory resolution, and the total analysis time was 18 min, including equilibration. The method was successfully applied in rapid screening of bile samples from the three mammals. Significant metabolic frameworks of bile acids among various species were observed, whereas considerable quantitative variations in both inter- and intraspecies were also observed, especially for gallstone patients. Our results suggest that detecting the change of bile acid profiles could be applied for the diagnosis of gallstone disease. © Crown copyright 2014.

  7. Effect of Nb on the Growth Behavior of Co3Sn2 Phase in Undercooled Co-Sn Melts

    Science.gov (United States)

    Kang, Jilong; Xu, Wanqiang; Wei, Xiuxun; Ferry, Michael; Li, Jinfu

    2016-12-01

    The growth behavior of the primary β-Co3Sn2 phase in (Co67Sn33)100- x Nb x ( x = 0, 0.5, 0.8, 1.0) hypereutectic alloys at different melt undercoolings was investigated systematically. The growth pattern of the β-Co3Sn2 phase at low undercooling changes with the Nb content from fractal seaweed ( x = 0, 0.5) into dendrite ( x = 0.8) and then returns to fractal seaweed ( x = 1.0) as a response to the changes in interface energy anisotropy and interface kinetic anisotropy. As undercooling increases, the dendritic growth of the β-Co3Sn2 phase in (Co67Sn33)99.2Nb0.8 alloy gives way to fractal seaweed growth at an undercooling of 32 K (-241 °C). At larger undercooling, the fractal seaweed growth is further replaced by compact seaweed growth, which occurred in the other three alloys investigated. The growth velocity of the β-Co3Sn2 phase slightly increases at low and intermediate undercooling but clearly decreases at larger undercooling due to the Nb addition. The growth velocity sharply increases as the growth pattern of the Co3Sn2 phase transits from fractal seaweed into compact seaweed.

  8. Red Guava Leaf Harvesting Impact on Flavonoid Optimation in Different Growth Phases

    Directory of Open Access Journals (Sweden)

    MUNIF GHULAMAHDI

    2011-06-01

    Full Text Available Harvesting process is a critical time to identify the quality of raw material for traditional medicine. The time and harvesting techniques, drying process after harvesting, and processing to make the simplicia, are the crucial role to make the good quality of the natural product. On the other hand, there is a lack of general understanding and appreciation about the processes involved in governing shoot and tree growth and development, i.e. red guava. The research objective was to evaluate the influence of leaf harvesting and growth phases on red guava for flavonoid production as antioxidant. Randomized factorial block design in time were laid out with two factors and followed by Duncan’s multiple range test. The treatments were the amount of leaf harvested on tertiary branches (0, 25, 50, and 100% and growth phases of the plant (vegetative and generative. Leaf harvesting 25% on tertiary branches significantly increased the leaf number (766.3 tree-1 and the number of new quarternary branches, decreasing leaf area index (LAI and leaf dry weight at the end of the experiment (22 weeks of observation/WO. The highest leaf dry weight (156.94 g tree-1 and LAI (0.47 was found in harvesting 25% tertiary branches. Harvesting 100% leaf on tertiary branches in vegetative phase significantly produced the lowest flavonoid production (7.82 g tree-1. The result suggested that flavonoid production from red guava leaves should be done by harvesting 50% leaf on tertiary branches in generative phase can be used to produce the highest flavonoid (89.90 g tree-1.

  9. Phase-field simulation of nucleation and growth of M{sub 23}C{sub 6} carbide and ferromagnetic phases during creep deformation in Type 304 steel

    Energy Technology Data Exchange (ETDEWEB)

    Tsukada, Yuhki, E-mail: tsukada@silky.numse.nagoya-u.ac.j [Department of Materials, Physics and Energy Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Shiraki, Atsuhiro; Murata, Yoshinori [Department of Materials, Physics and Energy Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Takaya, Shigeru [Japan Atomic Energy Agency, 4002 Narita-cho, O-arai-machi, Higashi-ibaraki-gun, Ibaraki 311-1393 (Japan); Koyama, Toshiyuki [National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan); Morinaga, Masahiko [Department of Materials, Physics and Energy Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan)

    2010-06-15

    A phase-field method was applied to the simulation of simultaneous nucleation and growth of both M{sub 23}C{sub 6} carbide and ferromagnetic {alpha} phases during the creep process in Type 304 steel. Nucleation events of these product phases were explicitly introduced through a probabilistic Poisson seeding process based on local nucleation rates that were calculated as a function of local concentration. The defect energy of the creep dislocations near the carbides, which increases during creep, was integrated into the nucleation driving force for the {alpha} phase. The simulation used in this study accurately reproduced changes in the amounts of the precipitated phases as a function of creep time. Furthermore, we examine the effect of the dislocation density on precipitation of the {alpha} phase, and show that the phase-field method is useful for examining the stochastic and kinetic phenomenon of phase transformation.

  10. Crystal growth of pure substances: Phase-field simulations in comparison with analytical and experimental results

    Science.gov (United States)

    Nestler, B.; Danilov, D.; Galenko, P.

    2005-07-01

    A phase-field model for non-isothermal solidification in multicomponent systems [SIAM J. Appl. Math. 64 (3) (2004) 775-799] consistent with the formalism of classic irreversible thermodynamics is used for numerical simulations of crystal growth in a pure material. The relation of this approach to the phase-field model by Bragard et al. [Interface Science 10 (2-3) (2002) 121-136] is discussed. 2D and 3D simulations of dendritic structures are compared with the analytical predictions of the Brener theory [Journal of Crystal Growth 99 (1990) 165-170] and with recent experimental measurements of solidification in pure nickel [Proceedings of the TMS Annual Meeting, March 14-18, 2004, pp. 277-288; European Physical Journal B, submitted for publication]. 3D morphology transitions are obtained for variations in surface energy and kinetic anisotropies at different undercoolings. In computations, we investigate the convergence behaviour of a standard phase-field model and of its thin interface extension at different undercoolings and at different ratios between the diffuse interface thickness and the atomistic capillary length. The influence of the grid anisotropy is accurately analyzed for a finite difference method and for an adaptive finite element method in comparison.

  11. Rapid Measurements of Aerosol Size Distribution and Hygroscopic Growth via Image Processing with a Fast Integrated Mobility Spectrometer (FIMS)

    Science.gov (United States)

    Wang, Y.; Pinterich, T.; Spielman, S. R.; Hering, S. V.; Wang, J.

    2017-12-01

    Aerosol size distribution and hygroscopicity are among key parameters in determining the impact of atmospheric aerosols on global radiation and climate change. In situ submicron aerosol size distribution measurements commonly involve a scanning mobility particle sizer (SMPS). The SMPS scanning time is in the scale of minutes, which is often too slow to capture the variation of aerosol size distribution, such as for aerosols formed via nucleation processes or measurements onboard research aircraft. To solve this problem, a Fast Integrated Mobility Spectrometer (FIMS) based on image processing was developed for rapid measurements of aerosol size distributions from 10 to 500 nm. The FIMS consists of a parallel plate classifier, a condenser, and a CCD detector array. Inside the classifier an electric field separates charged aerosols based on electrical mobilities. Upon exiting the classifier, the aerosols pass through a three stage growth channel (Pinterich et al. 2017; Spielman et al. 2017), where aerosols as small as 7 nm are enlarged to above 1 μm through water or heptanol condensation. Finally, the grown aerosols are illuminated by a laser sheet and imaged onto a CCD array. The images provide both aerosol concentration and position, which directly relate to the aerosol size distribution. By this simultaneous measurement of aerosols with different sizes, the FIMS provides aerosol size spectra nearly 100 times faster than the SMPS. Recent deployment onboard research aircraft demonstrated that the FIMS is capable of measuring aerosol size distributions in 1s (Figure), thereby offering a great advantage in applications requiring high time resolution (Wang et al. 2016). In addition, the coupling of the FIMS with other conventional aerosol instruments provides orders of magnitude more rapid characterization of aerosol optical and microphysical properties. For example, the combination of a differential mobility analyzer, a relative humidity control unit, and a FIMS was

  12. Phase diagram of interfacial growth modes by vapor deposition and its application for ZnO nanostructures

    Science.gov (United States)

    Shu, Da-Jun; Xiong, Xiang; Liu, Ming; Wang, Mu

    2017-09-01

    Interfacial growth from vapor has been extensively studied. However, a straightforward picture of the growth mode under different growth conditions is still lacking. In this paper, we develop a comprehensive interfacial growth theory based on the stochastic approach. Using a critical interisland separation, we construct a general phase diagram of the growth modes. It has been revealed that if the Ehrlich-Schwoebel barrier EES is smaller than a critical value, the interfacial growth proceeds in a layer-by-layer (LBL) mode at any deposition rate. However, if EES is larger than the critical value, LBL growth occurs only at very small or very large deposition rates relative to the intralayer hopping rate, and multilayer (ML) growth occurs at a moderate deposition rate. Experiments with zinc oxide growth by chemical vapor deposition have been designed to qualitatively demonstrate the theoretical model. By changing the flux of the carrier gas (nitrogen gas) in chemical vapor deposition, we realize LBL, ML, and then reentrance of LBL homoepitaxial growth of ZnO successively. Moreover, we find that surface kinetics of ZnO is suppressed by decreasing oxygen partial pressure by comparing the experimental observations and theoretical models, which is supported by our recent first-principles calculations. Since the influence of the substrate and the growth species on growth can approximately be represented by binding energy and surface kinetics, we suggest that the phase diagram is essential for interfacial growth of different materials by vapor deposition.

  13. SR phase contrast imaging to address the evolution of defects during SiC growth

    International Nuclear Information System (INIS)

    Argunova, Tatiana S.; Gutkin, Mikhail Yu.; Je, Jung Ho; Mokhov, Evgeniy N.; Nagalyuk, Sergey S.; Hwu, Yeukuang

    2011-01-01

    Sliced SiC boule grown by physical vapor transport is investigated using synchrotron white beam phase contrast imaging combined with Bragg diffraction. The evolution of defects is revealed. In the early growth stage, foreign polytype inclusions not only induce massive generation of full-core dislocations and dislocated micropipes but also attract them, forming slit-type pores at the boundaries of inclusions. In the intermediate stage, when inclusions stop to grow and become overgrown by the matrix, the pore density significantly reduces, which is attributed to their transformation into new micropipes. In the later stage, the micropipe density decreases, providing evidence for their partial annihilation and healing. Mechanisms for the evolution from inclusions to pores and finally to micropipes during the crystal growth are further discussed. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  14. Phase-field-lattice Boltzmann study for lamellar eutectic growth in a natural convection melt

    Directory of Open Access Journals (Sweden)

    Ang Zhang

    2017-11-01

    Full Text Available In the present study, the influence of natural convection on the lamellar eutectic growth is determined by a phase-field-lattice Boltzmann study for Al-Cu eutectic alloy. The mass difference resulting from concentration difference led to the fluid flow, and a robust parallel and adaptive mesh refinement algorithm was employed to improve the computational efficiency without any compromising accuracy. Results show that the existence of natural convection would affect the growth undercooling and thus control the interface shape by adjusting the lamellar width. In particular, by alternating the magnitude of the solute expansion coefficient, the strength of the natural convection is changed. Corresponding microstructure patterns are discussed and compared with those under no-convection conditions.

  15. Aluminum Gallium Nitride Alloys Grown via Metalorganic Vapor-Phase Epitaxy Using a Digital Growth Technique

    Science.gov (United States)

    Rodak, L. E.; Korakakis, D.

    2011-04-01

    This work investigates the use of a digital growth technique as a viable method for achieving high-quality aluminum gallium nitride (Al x Ga1- x N) films via metalorganic vapor-phase epitaxy. Digital alloys are superlattice structures with period thicknesses of a few monolayers. Alloys with an AlN mole fraction ranging from 0.1 to 0.9 were grown by adjusting the thickness of the AlN layer in the superlattice. High-resolution x-ray diffraction was used to determine the superlattice period and c-lattice parameter of the structure, while reciprocal-space mapping was used to determine the a-lattice parameter and evaluate growth coherency. A comparison of the measured lattice parameter with both the nominal value and also the underlying buffer layer is discussed.

  16. Gold catalyzed nickel disilicide formation: a new solid-liquid-solid phase growth mechanism.

    Science.gov (United States)

    Tang, Wei; Picraux, S Tom; Huang, Jian Yu; Liu, Xiaohua; Tu, K N; Dayeh, Shadi A

    2013-01-01

    The vapor-liquid-solid (VLS) mechanism is the predominate growth mechanism for semiconductor nanowires (NWs). We report here a new solid-liquid-solid (SLS) growth mechanism of a silicide phase in Si NWs using in situ transmission electron microcopy (TEM). The new SLS mechanism is analogous to the VLS one in relying on a liquid-mediating growth seed, but it is fundamentally different in terms of nucleation and mass transport. In SLS growth of Ni disilicide, the Ni atoms are supplied from remote Ni particles by interstitial diffusion through a Si NW to the pre-existing Au-Si liquid alloy drop at the tip of the NW. Upon supersaturation of both Ni and Si in Au, an octahedral nucleus of Ni disilicide (NiSi2) forms at the center of the Au liquid alloy, which thereafter sweeps through the Si NW and transforms Si into NiSi2. The dissolution of Si by the Au alloy liquid mediating layer proceeds with contact angle oscillation at the triple point where Si, oxide of Si, and the Au alloy meet, whereas NiSi2 is grown from the liquid mediating layer in an atomic stepwise manner. By using in situ quenching experiments, we are able to measure the solubility of Ni and Si in the Au-Ni-Si ternary alloy. The Au-catalyzed mechanism can lower the formation temperature of NiSi2 by 100 °C compared with an all solid state reaction.

  17. A solid-phase extraction method for rapidly determining the adsorption coefficient of pharmaceuticals in sewage sludge

    Science.gov (United States)

    Berthod, Laurence; Roberts, Gary; Whitley, David C.; Sharpe, Alan; Mills, Graham A.

    2014-01-01

    The partitioning of pharmaceuticals in the environment can be assessed by measuring their adsorption coefficients (Kd) between aqueous and solid phases. Measuring this coefficient in sewage sludge gives an indication of their partitioning behaviour in a wastewater treatment plant and hence contributes to an understanding of their subsequent fate. The regulatory approved method for measuring Kd in sewage sludge is the US Environmental Protection Agency's Office of Prevention, Pesticides and Toxic Substances (OPPTS) guideline 835.1110, which is labour intensive and time consuming. We describe an alternative method for measuring the Kd of pharmaceuticals in sewage sludge using a modified solid-phase extraction (SPE) technique. SPE cartridges were packed at different sludge/PTFE ratios (0.4, 6.0, 24.0 and 40.0% w/w sludge) and eluted with phosphate buffer at pH 7.4. The approach was tested initially using three pharmaceuticals (clofibric acid, diclofenac and oxytetracycline) that covered a range of Kd values. Subsequently, the sorption behaviour of ten further pharmaceuticals with varying physico-chemical properties was evaluated. Results from the SPE method were comparable to those of the OPPTS test, with a correlation coefficient of 0.93 between the two approaches. SPE cartridges packed with sludge and PTFE were stable for up to one year; use within one month reduced variability in measurements (to a maximum of 0.6 log units). The SPE method is low-cost, easy to use and enables the rapid measurement of Kd values for a large number of chemicals. It can be used as an alternative to the more laborious full OPPTS test in environmental fate studies and risk assessments. PMID:25299795

  18. Galaxy interactions trigger rapid black hole growth: An unprecedented view from the Hyper Suprime-Cam survey

    Science.gov (United States)

    Goulding, Andy D.; Greene, Jenny E.; Bezanson, Rachel; Greco, Johnny; Johnson, Sean; Leauthaud, Alexie; Matsuoka, Yoshiki; Medezinski, Elinor; Price-Whelan, Adrian M.

    2018-01-01

    Collisions and interactions between gas-rich galaxies are thought to be pivotal stages in their formation and evolution, causing the rapid production of new stars, and possibly serving as a mechanism for fueling supermassive black holes (BHs). Harnessing the exquisite spatial resolution (˜0{^''.}5) afforded by the first ˜170 deg2 of the Hyper Suprime-Cam (HSC) survey, we present our new constraints on the importance of galaxy-galaxy major mergers (1 : 4) in growing BHs throughout the last ˜8 Gyr. Utilizing mid-infrared observations in the WISE all-sky survey, we robustly select active galactic nuclei (AGN) and mass-matched control galaxy samples, totaling ˜140000 spectroscopically confirmed systems at i based on our comparison of AGN fractions in mass-matched samples, we determine that the most luminous AGN population (LAGN ≳ 1045 erg s-1) systematically reside in merging systems over non-interacting galaxies. Our findings show that galaxy-galaxy interactions do, on average, trigger luminous AGN activity substantially more often than in secularly evolving non-interacting galaxies, and we further suggest that the BH growth rate may be closely tied to the dynamical time of the merger system.

  19. Nanoscale Phase Stability Reversal During the Nucleation and Growth of Titanium Oxide Minerals

    Science.gov (United States)

    Hummmer, D. R.; Heaney, P. J.; Kubicki, J. D.; Kent, P. R.; Post, J. E.

    2008-12-01

    Fine-grained titanium oxide minerals are important in soils, where they affect a variety of geochemical processes. They are also industrially important as catalysts, pigments, food additives, and dielectrics. Recent research has indicated an apparent reversal of thermodynamic stability between TiO2 phases at the nanoscale thought to be caused by an increased contribution of surface energy to the total free energy. Time-resolved X-ray diffraction (XRD) experiments in which titanium oxides crystallize from aqueous TiCl4 solutions confirm that anatase, a metastable phase, is always the first phase to nucleate under our range of initial conditions. Rutile peaks are observed only minutes after the first appearance of anatase, after which anatase abundance slowly decreases while rutile continues to form. Whole pattern refinement of diffraction data reveals that lattice constants of both phases increase throughout the crystallization process. In addition, transmission electron microscope (TEM) observations and kinetic modeling indicate that anatase does not undergo a solid-state transformation to the rutile structure as once thought. Instead, anatase appears to re-dissolve and then feed the growth of already nucleated rutile nanocrystals. Density functional theory (DFT) calculations were employed to model 1, 2, and 3 nm particles of both mineral phases. The total surface energies calculated from these models did yield lower values for anatase than for rutile by 8-13 kJ/mol depending on particle size, indicating that surface free energy is sufficient to account for stability reversal. However, these whole-particle surface energies were much higher than the sum of energies of each particle's constituent crystallographic surfaces. We attribute the excess energy to defects associated with the edges and corners of nanoparticles, which are not present on a 2-D periodic surface. This previously unreported edge and corner energy may play a dominant role in the stability reversal

  20. An investigation into the rapid removal of tetracycline using multilayered graphene-phase biochar derived from waste chicken feather.

    Science.gov (United States)

    Li, Huiqin; Hu, Jingtao; Meng, Yue; Su, Jinhua; Wang, Xiaojing

    2017-12-15

    This study investigated the removal of tetracycline (TC) using multilayered graphene-phase biochar (MGB) derived from waste chicken feather. MGB was produced through a two-stage carbonization and KOH-activation method. MGB was characterized by scanning electron microscopy (SEM), transmission electron microscope (TEM), Fourier transform infrared (FT-IR), Raman spectra, Zeta potential and elemental analysis. Various chemical functional groups were demonstrated on the surface of MGB. MGB was featured by a very large BET surface area of 1838m 2 /g. A rapid equilibrium (within 30s) and an ultrahigh removal efficiency (up to 99.65%) were obtained when MGB was used in the adsorption of TCs. The adsorption processes were temperature-dependent and the maximum adsorption capacity of MGB was 388.33mg/g at 30°C. The data of adsorption isotherms and kinetics were represented well by the Langmuir and Elovich models, respectively. The chemical monolayer adsorption could play an important role in this process. Furthermore, the adsorption of MGB was tolerant with wide pH, high ionic strength and even co-existing anions. Regeneration experiments indicated the removal efficiency was still satisfied (96.61%) even after four cycles. These results have important implications for the future application of animal waste-derived adsorbents in the treatment of wastewater containing antibiotic residues. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Rapid Determination of Clenbuterol in Pork by Direct Immersion Solid-Phase Microextraction Coupled with Gas Chromatography-Mass Spectrometry.

    Science.gov (United States)

    Ye, Diru; Wu, Susu; Xu, Jianqiao; Jiang, Ruifen; Zhu, Fang; Ouyang, Gangfeng

    2016-02-01

    Direct immersion solid-phase microextraction (DI-SPME) coupled with gas chromatography-mass spectrometry (GC-MS) was developed for rapid analysis of clenbuterol in pork for the first time. In this work, a low-cost homemade 44 µm polydimethylsiloxane (PDMS) SPME fiber was employed to extract clenbuterol in pork. After extraction, derivatization was performed by suspending the fiber in the headspace of the 2 mL sample vial saturated with a vapor of 100 µL hexamethyldisilazane. Lastly, the fiber was directly introduced to GC-MS for analysis. All parameters that influenced absorption (extraction time), derivatization (derivatization reagent, time and temperature) and desorption (desorption time) were optimized. Under optimized conditions, the method offered a wide linear range (10-1000 ng g(-1)) and a low detection limit (3.6 ng g(-1)). Finally, the method was successfully applied in the analysis of pork from the market, and recoveries of the method for spiked pork were 97.4-105.7%. Compared with the traditional solvent extraction method, the proposed method was much cheaper and fast. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  2. Stabilisation of late transition metal and noble metal films in hexagonal and body centred tetragonal phases by epitaxial growth

    Energy Technology Data Exchange (ETDEWEB)

    Hueger, E.

    2005-08-26

    In this work ultrathin metallic films with a crystal phase different to their natural bulk structure were produced by hetero-epitaxial growth on metallic substrates. A further aim of this work was to understand the initiation, growth and stability of crystal phase modifications of these films. there exist cases where the films turn beyond the pseudomorphic-growth to a crystal phase different from their natural bulk structure. The present work presents and discusses such a case in addition to the general phenomenon of pseudomorphic-growth. In particular it is shown that metals whose natural phase is face centred cubic (fcc) can be grown in body centred tetragonal (bct) or hexagonal close packed (hcp) phases in the form of thin films on (001) surfaces of appropriate substrates. The growth behavior, electron diffraction analysis, appearance conditions, geometric fit considerations, examples and a discussion of the phase stability of non-covered films and superlattices is given reviewing all epitaxial-systems whose diffraction pattern can be explained by the hexagonal or pseudomorphic bct phase. (orig.)

  3. The Faceted Discrete Growth and Phase Differentiation During the Directional Solidification of 20SiMnMo5 Steel

    Science.gov (United States)

    Ma, Xiaoping; Li, Dianzhong

    2018-03-01

    The microstructures, segregation and cooling curve were investigated in the directional solidification of 20SiMnMo5 steel. The typical characteristic of faceted growth is identified. The microstructures within the single cellular and within the single dendritic arm, together with the contradictive segregation distribution against the cooling curve, verify the discrete crystal growth in multi-scales. Not only the single cellular/dendritic arm but also the single martensite zone within the single cellular/dendritic arm is produced by the discrete growth. In the viewpoint of segregation, the basic domain following continuous growth has not been revealed. Along with the multi-scale faceted discrete growth, the phase differentiation happens for both the solid and liquid. The differentiated liquid phases appear and evolve with different sizes, positions, compositions and durations. The physical mechanism for the faceted discrete growth is qualitatively established based on the nucleation of new faceted steps induced by the composition gradient and temperature gradient.

  4. The Faceted Discrete Growth and Phase Differentiation During the Directional Solidification of 20SiMnMo5 Steel

    Science.gov (United States)

    Ma, Xiaoping; Li, Dianzhong

    2018-07-01

    The microstructures, segregation and cooling curve were investigated in the directional solidification of 20SiMnMo5 steel. The typical characteristic of faceted growth is identified. The microstructures within the single cellular and within the single dendritic arm, together with the contradictive segregation distribution against the cooling curve, verify the discrete crystal growth in multi-scales. Not only the single cellular/dendritic arm but also the single martensite zone within the single cellular/dendritic arm is produced by the discrete growth. In the viewpoint of segregation, the basic domain following continuous growth has not been revealed. Along with the multi-scale faceted discrete growth, the phase differentiation happens for both the solid and liquid. The differentiated liquid phases appear and evolve with different sizes, positions, compositions and durations. The physical mechanism for the faceted discrete growth is qualitatively established based on the nucleation of new faceted steps induced by the composition gradient and temperature gradient.

  5. Orientation selection process during the early stage of cubic dendrite growth: A phase-field crystal study

    International Nuclear Information System (INIS)

    Tang Sai; Wang Zhijun; Guo Yaolin; Wang Jincheng; Yu Yanmei; Zhou Yaohe

    2012-01-01

    Using the phase-field crystal model, we investigate the orientation selection of the cubic dendrite growth at the atomic scale. Our simulation results reproduce how a face-centered cubic (fcc) octahedral nucleus and a body-centered cubic (bcc) truncated-rhombic dodecahedral nucleus choose the preferred growth direction and then evolve into the dendrite pattern. The interface energy anisotropy inherent in the fcc crystal structure leads to the fastest growth velocity in the 〈1 0 0〉 directions. New { 1 1 1} atomic layers prefer to nucleate at positions near the tips of the fcc octahedron, which leads to the directed growth of the fcc dendrite tips in the 〈1 0 0〉 directions. A similar orientation selection process is also found during the early stage of bcc dendrite growth. The orientation selection regime obtained by phase-field crystal simulation is helpful for understanding the orientation selection processes of real dendrite growth.

  6. Hydride vapor phase epitaxy growth of GaN, InGaN, ScN, and ScAIN

    NARCIS (Netherlands)

    Bohnen, T.

    2010-01-01

    Chemical vapor deposition (CVD); hydride vapor phase epitaxy (HVPE); gallium nitride (GaN); indium gallium nitride (InGaN); scandium nitride (ScN); scandium aluminum nitride (ScAlN); semiconductors; thin films; nanowires; III nitrides; crystal growth - We studied the HVPE growth of different III

  7. Polycrystalline indium phosphide on silicon by indium assisted growth in hydride vapor phase epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Metaferia, Wondwosen; Sun, Yan-Ting, E-mail: yasun@kth.se; Lourdudoss, Sebastian [Laboratory of Semiconductor Materials, Department of Materials and Nano Physics, KTH—Royal Institute of Technology, Electrum 229, 164 40 Kista (Sweden); Pietralunga, Silvia M. [CNR-Institute for Photonics and Nanotechnologies, P. Leonardo da Vinci, 32 20133 Milano (Italy); Zani, Maurizio; Tagliaferri, Alberto [Department of Physics Politecnico di Milano, P. Leonardo da Vinci, 32 20133 Milano (Italy)

    2014-07-21

    Polycrystalline InP was grown on Si(001) and Si(111) substrates by using indium (In) metal as a starting material in hydride vapor phase epitaxy (HVPE) reactor. In metal was deposited on silicon substrates by thermal evaporation technique. The deposited In resulted in islands of different size and was found to be polycrystalline in nature. Different growth experiments of growing InP were performed, and the growth mechanism was investigated. Atomic force microscopy and scanning electron microscopy for morphological investigation, Scanning Auger microscopy for surface and compositional analyses, powder X-ray diffraction for crystallinity, and micro photoluminescence for optical quality assessment were conducted. It is shown that the growth starts first by phosphidisation of the In islands to InP followed by subsequent selective deposition of InP in HVPE regardless of the Si substrate orientation. Polycrystalline InP of large grain size is achieved and the growth rate as high as 21 μm/h is obtained on both substrates. Sulfur doping of the polycrystalline InP was investigated by growing alternating layers of sulfur doped and unintentionally doped InP for equal interval of time. These layers could be delineated by stain etching showing that enough amount of sulfur can be incorporated. Grains of large lateral dimension up to 3 μm polycrystalline InP on Si with good morphological and optical quality is obtained. The process is generic and it can also be applied for the growth of other polycrystalline III–V semiconductor layers on low cost and flexible substrates for solar cell applications.

  8. Near-earth Thin Current Sheets and Birkeland Currents during Substorm Growth Phase

    International Nuclear Information System (INIS)

    Sorin Zaharia; Cheng, C.Z.

    2003-01-01

    Two important phenomena observed during the magnetospheric substorm growth phase are modeled: the formation of a near-Earth (|X| ∼ 9 R E ) thin cross-tail current sheet, as well as the equatorward shift of the ionospheric Birkeland currents. Our study is performed by solving the 3-D force-balance equation with realistic boundary conditions and pressure distributions. The results show a cross-tail current sheet with large current (J φ ∼ 10 nA/m 2 ) and very high plasma β (β ∼ 40) between 7 and 10 R E . The obtained region-1 and region-2 Birkeland currents, formed on closed field lines due to pressure gradients, move equatorward and become more intense (J parallel max ∼ 3 (micro)A/m 2 ) compared to quiet times. Both results are in agreement with substorm growth phase observations. Our results also predict that the cross-tail current sheet maps into the ionosphere in the transition region between the region-1 and region-2 currents

  9. Self-consistent quasi-static radial transport during the substorm growth phase

    Science.gov (United States)

    Le Contel, O.; Pellat, R.; Roux, A.

    2000-06-01

    We develop a self-consistent description of the slowly changing magnetic configuration of the near-Earth plasma sheet (NEPS) during substorm growth phase. This new approach is valid for quasi-static fluctuations ωcurrent. The quasi-neutrality condition (QNC) is solved via an expansion in the small parameter Te/Ti (Te/Ti is the ratio between the electronic and ionic temperatures). To the lowest order in Te/Ti, we find that the enforcement of QNC implies the presence of a global electrostatic potential which is constant for a given magnetic field line but varies across the magnetic field. The corresponding electric field shields the effect of the inductive component of the electric field, thereby producing a partial reduction of the motion that would correspond to the inductive electric field. Furthermore, we show that enforcing the QNC implies a field-aligned potential drop which is computed to the next order in Te/Ti in a companion paper [Le Contel et al., this issue]. In the present paper, we show that the direction of the azimuthal electric field varies along the field line, thus the equatorial electric field cannot be mapped onto the ionosphere. Furthermore during the growth phase, the (total) azimuthal electric field is directed eastward, close to the equator, and westward, off-equator. Thus large equatorial pitch angle particles drift tailward, whereas small pitch angle particles drift earthward.

  10. Effect of growth phase on harvesting characteristics, autoflocculation and lipid content of Ettlia texensis for microalgal biodiesel production

    NARCIS (Netherlands)

    Salim, S.; Shi, Z.; Vermuë, M.H.; Wijffels, R.H.

    2013-01-01

    The effect of growth phase on the recovery of the autoflocculating microalgae Ettlia texensis was studied. In the stationary phase, 90% recovery was achieved after 3 h settling. Scanning electron microscopic pictures revealed that extracellular polymeric substances (EPS) on the cell surface were

  11. Liquid phase electro epitaxy growth kinetics of GaAs-A three-dimensional numerical simulation study

    International Nuclear Information System (INIS)

    Mouleeswaran, D.; Dhanasekaran, R.

    2006-01-01

    A three-dimensional numerical simulation study for the liquid phase electro epitaxial growth kinetic of GaAs is presented. The kinetic model is constructed considering (i) the diffusive and convective mass transport, (ii) the heat transfer due to thermoelectric effects such as Peltier effect, Joule effect and Thomson effect, (iii) the electric current distribution with electromigration and (iv) the fluid flow coupled with concentration and temperature fields. The simulations are performed for two configurations namely (i) epitaxial growth from the arsenic saturated gallium rich growth solution, i.e., limited solution model and (ii) epitaxial growth from the arsenic saturated gallium rich growth solution with polycrystalline GaAs feed. The governing equations of liquid phase electro epitaxy are solved numerically with appropriate initial and boundary conditions using the central difference method. Simulations are performed to determine the following, a concentration profiles of solute atoms (As) in the Ga-rich growth solution, shape of the substrate evolution, the growth rate of the GaAs epitaxial film, the contributions of Peltier effect and electromigration of solute atoms to the growth with various experimental growth conditions. The growth rate is found to increase with increasing growth temperature and applied current density. The results are discussed in detail

  12. Growth of NH4Cl Single Crystal from Vapor Phase in Vertical Furnace

    Science.gov (United States)

    Nigara, Yutaka; Yoshizawa, Masahito; Fujimura, Tadao

    1983-02-01

    A pure and internally stress-free single crystal of NH4Cl was grown successfully from the vapor phase. The crystal measured 1.6 cmφ× 2 cm and had the disordered CsCl structure, which was stable below 184°C. The crystal was grown in an ampoule in a vertical furnace, in which the vapor was efficiently transported both by diffusion and convection. In line with the growth mechanism of a single crystal, the temperature fluctuation (°C/min) on the growth interface was kept smaller than the product of the temperature gradient (°C/cm) and the growth rate (cm/min). The specific heat of the crystal was measured around -31°C (242 K) during cooling and heating cycles by AC calorimetry. The thermal hysteresis (0.4 K) obtained here was smaller than that (0.89 K) of an NH4Cl crystal grown from its aqueous solution with urea added as a habit modifier.

  13. Rapid growth and genetic diversity retention in an isolated reintroduced black bear population in the central appalachians

    Science.gov (United States)

    Murphy, Sean M.; Cox, John J.; Clark, Joseph D.; Augustine, Benjamin J.; Hast, John T.; Gibbs, Dan; Strunk, Michael; Dobey, Steven

    2015-01-01

    Animal reintroductions are important tools of wildlife management to restore species to their historical range, and they can also create unique opportunities to study population dynamics and genetics from founder events. We used non-invasive hair sampling in a systematic, closed-population capture-mark-recapture (CMR) study design at the Big South Fork (BSF) area in Kentucky during 2010 and Tennessee during 2012 to estimate the demographic and genetic characteristics of the black bear (Ursus americanus) population that resulted from a reintroduced founding population of 18 bears in 1998. We estimated 38 (95% CI: 31–66) and 190 (95% CI: 170–219) bears on the Kentucky and Tennessee study areas, respectively. Based on the Tennessee abundance estimate alone, the mean annual growth rate was 18.3% (95% CI: 17.4–19.5%) from 1998 to 2012. We also compared the genetic characteristics of bears sampled during 2010–2012 to bears in the population during 2000–2002, 2–4 years following reintroduction, and to the source population. We found that the level of genetic diversity since reintroduction as indicated by expected heterozygosity (HE) remained relatively constant (HE(source, 2004) = 0.763, HE(BSF, 2000–2002) = 0.729, HE(BSF, 2010–2012) = 0.712) and the effective number of breeders (NB) remained low but had increased since reintroduction in the absence of sufficient immigration (NB(BSF, 2000–2002) = 12, NB(BSF, 2010–2012)  = 35). This bear population appears to be genetically isolated, but contrary to our expectations, we did not find evidence of genetic diversity loss or other deleterious genetic effects typically observed from small founder groups. We attribute that to high initial genetic diversity in the founder group combined with overlapping generations and rapid population growth. Although the population remains relatively small, the reintroduction using a small founder group appears to be demographically and genetically

  14. Isocratic Solid Phase Extraction-Liquid Chromatography (SPE-LC) Interfaced to High-Performance Tandem Mass Spectrometry for Rapid Protein Identification

    DEFF Research Database (Denmark)

    Hørning, Ole B; Kjeldsen, Frank; Theodorsen, Søren

    2008-01-01

    the isocratic solid phase extraction-liquid chromatography (SPE-LC) technology for rapid separation ( approximately 8 min) of simple peptide samples. We now extend these studies to demonstrate the potential of SPE-LC separation in combination with a hybrid linear ion trap-Orbitrap tandem mass spectrometer...

  15. An on-line normal-phase high performance liquid chromatography method for the rapid detection of radical scavengers in non-polar food matrixes

    NARCIS (Netherlands)

    Zhang, Q.; Klift, van der E.J.C.; Janssen, H.G.; Beek, van T.A.

    2009-01-01

    An on-line method for the rapid pinpointing of radical scavengers in non-polar mixtures like vegetable oils was developed. To avoid problems with dissolving the sample, normal-phase chromatography on bare silica gel was used with mixtures of hexane and methyl tert-butyl ether as the eluent. The high

  16. Rapid growth of black holes accompanied with hot or warm outflows exposed to anisotropic super-Eddington radiation

    Science.gov (United States)

    Takeo, Eishun; Inayoshi, Kohei; Ohsuga, Ken; Takahashi, Hiroyuki R.; Mineshige, Shin

    2018-05-01

    We perform two-dimensional radiation hydrodynamical simulations of accretion flows on to a black hole (BH) with a mass of 103 ≤ MBH/ M⊙ ≲ 106 in order to study rapid growth of BHs in the early Universe. For spherically symmetric flows, hyper-Eddington accretion from outside the Bondi radius can occur unimpeded by radiation feedback when MBH ≳ 104 M⊙(n∞/105 cm - 3) - 1(T∞/104 K)3/2, where the density and temperature of ambient gas are initially set to n∞ = 105 cm-3 and T∞ = 104 K. Here, we study accretion flows exposed to anisotropic radiation from a nuclear accretion disc with a luminosity higher than the Eddington value (LEdd) due to collimation towards the bipolar directions. We find that, unlike the spherically symmetric case, even less massive BHs with MBH ionized regions expand towards the poles producing hot outflows with T ˜ 105 K. For more massive BHs with MBH ≳ 5 × 105 M⊙, intense inflows of neutral gas through the equator totally cover the central radiating region due to the non-radial gas motions. Because of efficient recombination by hydrogen, the entire flow settles in neutral and warm gas with T ≃ 8000 K. The BH is fed at a rate of ˜5 × 104LEdd/c2 (a half of the inflow rate from the Bondi radius). Moreover, radiation momentum absorbed by neutral hydrogen produces warm outflows towards the bipolar directions at ˜ 10 per cent of the BH feeding rate and with a velocity several times higher than the escaping value.

  17. Investigations on the growth kinetics of Laves phase precipitates in 12% Cr creep-resistant steels: Experimental and DICTRA calculations

    Energy Technology Data Exchange (ETDEWEB)

    Prat, O. [Max Planck Institute fuer Eisenforschung GmbH, Max Planck Strasse 1, 40237 Duesseldorf (Germany)] [Universidad de Concepcion, Departamento de Ingenieria de Materiales, Edmundo Larenas 270, Concepcion (Chile); Garcia, J., E-mail: jose.garcia@helmholtz-berlin.de [Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); Rojas, D. [Max Planck Institute fuer Eisenforschung GmbH, Max Planck Strasse 1, 40237 Duesseldorf (Germany); Carrasco, C. [Universidad de Concepcion, Departamento de Ingenieria de Materiales, Edmundo Larenas 270, Concepcion (Chile); Inden, G. [Max Planck Institute fuer Eisenforschung GmbH, Max Planck Strasse 1, 40237 Duesseldorf (Germany)

    2010-10-15

    The growth kinetics of Laves phase precipitates (type Fe{sub 2}W) in the early stage of creep (650 deg. C for 10,000 h) in two 12% Cr ferrite-martensitic steels has been investigated. In one alloy the Laves phase formed on tempering, while in the second alloy the Laves phase precipitated during creep. Kinetic simulations were performed using the software DICTRA. The particle size of the Laves phase was measured on transmission electron microscopy samples. The equilibrium phase fraction of the Laves phase was reached in the first thousand hours. Simulations of particle growth showed good agreement with the experimental results. Competitive growth between M{sub 23}C{sub 6} and the Laves phase showed that M{sub 23}C{sub 6} carbides reached their equilibrium after 12 days, whereas the Laves phase reached equilibrium after 3 months. Simulations of the influence of the interfacial energy and addition of Co, Cu and Si on Laves phase precipitation are presented.

  18. beta Phase Growth and Precipitation in the 5xxx Series Aluminum Alloy System

    Science.gov (United States)

    Scotto D'Antuono, Daniel

    The 5xxx series aluminum alloys are commonly used for structural applications due to their high strength to weight ratio, corrosion resistance, and weldability. This material system is a non-heat treatable aluminum and derives its strength from a super saturation of magnesium (3%>), and from cold rolling. While these materials have many admiral properties, they can undergo a process known as sensitization when exposed to elevated temperatures (50-280°C) for extended periods of time. During this process, magnesium segregates toward the grain boundaries and forms the secondary precipitate β phase (Al3Mg2). When exposed to harsh environments such as sea water, a galvanic couple is formed between the Al matrix and the β phase precipitates. The precipitates become anodic to the matrix and preferentially dissolve leaving gaps along the boundary network, ultimately leading to stress corrosion cracking. While this problem has been known to occur for some time now, questions relating to nucleation sites, misorientation dependence, effect of prior strain, and preferred temperature regimes remain unanswered. The work contained in this thesis attempted to better understand the kinetics, growth, and misorientation dependence, of β phase precipitation using in situ transmission electron microscopy experiments which allowed for direct visualization of the precipitation process. Orientation imaging using a Nanomegas/ASTAR system (OIM in TEM) coupled with the in situ experiments, along with elemental STEM EELs mapping were used to better understand the diffusion of Mg and found low angle boundaries as potential sites for nucleation. The resulting STEM EELs experiments also showed that Mg is much more stable at the grain boundaries than previously thought. Concurrent bulk ex-situ studies were used to compare various heat treatments, as well as to failed in service material showing that the low temperature treatments yield the metastable β’ phase more readily than the

  19. Temporal transcriptomic analysis of Desulfovibrio vulgaris Hildenborough transition into stationary phase growth during electrondonor depletion

    Energy Technology Data Exchange (ETDEWEB)

    Clark, M.E.; He, Q.; He, Z.; Huang, K.H.; Alm, E.J.; Wan, X.-F.; Hazen, T.C.; Arkin, A.P.; Wall, J.D.; Zhou, J.-Z.; Fields, M.W.

    2006-08-01

    Desulfovibrio vulgaris was cultivated in a defined medium, and biomass was sampled for approximately 70 h to characterize the shifts in gene expression as cells transitioned from the exponential to the stationary phase during electron donor depletion. In addition to temporal transcriptomics, total protein, carbohydrate, lactate, acetate, and sulfate levels were measured. The microarray data were examined for statistically significant expression changes, hierarchical cluster analysis, and promoter element prediction and were validated by quantitative PCR. As the cells transitioned from the exponential phase to the stationary phase, a majority of the down-expressed genes were involved in translation and transcription, and this trend continued at the remaining times. There were general increases in relative expression for intracellular trafficking and secretion, ion transport, and coenzyme metabolism as the cells entered the stationary phase. As expected, the DNA replication machinery was down-expressed, and the expression of genes involved in DNA repair increased during the stationary phase. Genes involved in amino acid acquisition, carbohydrate metabolism, energy production, and cell envelope biogenesis did not exhibit uniform transcriptional responses. Interestingly, most phage-related genes were up-expressed at the onset of the stationary phase. This result suggested that nutrient depletion may affect community dynamics and DNA transfer mechanisms of sulfate-reducing bacteria via the phage cycle. The putative feoAB system (in addition to other presumptive iron metabolism genes) was significantly up-expressed, and this suggested the possible importance of Fe{sup 2+} acquisition under metal-reducing conditions. The expression of a large subset of carbohydrate-related genes was altered, and the total cellular carbohydrate levels declined during the growth phase transition. Interestingly, the D. vulgaris genome does not contain a putative rpoS gene, a common attribute

  20. Rapid, specific determination of iodine and iodide by combined solid-phase extraction/diffuse reflectance spectroscopy

    Science.gov (United States)

    Arena, Matteo P.; Porter, Marc D.; Fritz, James S.

    2002-01-01

    A new, rapid methodology for trace analysis using solid-phase extraction is described. The two-step methodology is based on the concentration of an analyte onto a membrane disk and on the determination by diffuse reflectance spectroscopy of the amount of analyte extracted on the disk surface. This method, which is adaptable to a wide range of analytes, has been used for monitoring ppm levels of iodine and iodide in spacecraft water. Iodine is used as a biocide in spacecraft water. For these determinations, a water sample is passed through a membrane disk by means of a 10-mL syringe that is attached to a disk holder assembly. The disk, which is a polystyrene-divinylbenzene composite, is impregnated with poly(vinylpyrrolidone) (PVP), which exhaustively concentrates iodine as a yellow iodine-PVP complex. The amount of concentrated iodine is then determined in only 2 s by using a hand-held diffuse reflectance spectrometer by comparing the result with a calibration curve based on the Kubelka-Munk function. The same general procedure can be used to determine iodide levels after its facile and exhaustive oxidation to iodine by peroxymonosulfate (i.e., Oxone reagent). For samples containing both analytes, a two-step procedure can be used in which the iodide concentration is calculated from the difference in iodine levels before and after treatment of the sample with peroxymonosulfate. With this methodology, iodine and iodide levels in the 0.1-5.0 ppm range can be determined with a total workup time of approximately 60 s with a RSD of approximately 6%.

  1. Determination of the rate of crystal growth from the gas phase under conditions of turbulent free convection

    Science.gov (United States)

    Alad'Ev, S. I.

    1987-04-01

    Crystal growth in vertical and horizontal cylindrical vials, with the substrate and the source serving as the vial ends, is investigated analytically, assuming that the medium consists of a binary mixture of an active and an inert gas. The active gas is made up of the gaseous products of reactions taking place at the substrate and at the source. It is shown that turbulent free convection leads to an increase in crystal growth rate. All other conditions being equal, crystal growth in vertical vials is greater than that in horizontal ones; in both cases crystal growth rate increases with the vial radius, temperature gradient in the gas phase, and gas phase density. The results are compared with experimental data on the growth of Ge crystals in the Ge-GeI4 system.

  2. Effect of Strain Restored Energy on Abnormal Grain Growth in Mg Alloy Simulated by Phase Field Methods

    Science.gov (United States)

    Wu, Yan; Huang, Yuan-yuan

    2018-03-01

    Abnormal grain growth of single phase AZ31 Mg alloy in the spatio-temporal process has been simulated by phase field models, and the influencing factors of abnormal grain growth are studied in order to find the ways to control secondary recrystallization in the microstructure. The study aims to find out the mechanisms for abnormal grain growth in real alloys. It is shown from the simulated results that the abnormal grain growth can be controlled by the strain restored energy. Secondary recrystallization after an annealing treatment can be induced if there are grains of a certain orientation in the microstructure with local high restored energy. However, if the value of the local restored energy at a certain grain orientation is not greater than 1.1E 0, there may be no abnormal grain growth in the microstructure.

  3. Using an aqueous two-phase polymer-salt system to rapidly concentrate viruses for improving the detection limit of the lateral-flow immunoassay.

    Science.gov (United States)

    Jue, Erik; Yamanishi, Cameron D; Chiu, Ricky Y T; Wu, Benjamin M; Kamei, Daniel T

    2014-12-01

    The development of point-of-need (PON) diagnostics for viruses has the potential to prevent pandemics and protects against biological warfare threats. Here we discuss the approach of using aqueous two-phase systems (ATPSs) to concentrate biomolecules prior to the lateral-flow immunoassay (LFA) for improved viral detection. In this paper, we developed a rapid PON detection assay as an extension to our previous proof-of-concept studies which used a micellar ATPS. We present our investigation of a more rapid polymer-salt ATPS that can drastically improve the assay time, and show that the phase containing the concentrated biomolecule can be extracted prior to macroscopic phase separation equilibrium without affecting the measured biomolecule concentration in that phase. We could therefore significantly decrease the time of the diagnostic assay with an early extraction time of just 30 min. Using this rapid ATPS, the model virus bacteriophage M13 was concentrated between approximately 2 and 10-fold by altering the volume ratio between the two phases. As the extracted virus-rich phase contained a high salt concentration which destabilized the colloidal gold indicator used in LFA, we decorated the gold nanoprobes with polyethylene glycol (PEG) to provide steric stabilization, and used these nanoprobes to demonstrate a 10-fold improvement in the LFA detection limit. Lastly, a MATLAB script was used to quantify the LFA results with and without the pre-concentration step. This approach of combining a rapid ATPS with LFA has great potential for PON applications, especially as greater concentration-fold improvements can be achieved by further varying the volume ratio. Biotechnol. Bioeng. 2014;111: 2499-2507. © 2014 Wiley Periodicals, Inc. © 2014 Wiley Periodicals, Inc.

  4. Measuring laves phase particle size and thermodynamic calculating its growth and coarsening behavior in P92 steels

    DEFF Research Database (Denmark)

    Yao, Bing-Yin; Zhou, Rong-Can; Fan, Chang-Xin

    2010-01-01

    The growth of Laves phase particles in three kinds of P92 steels were investigated. Laves phase particles can be easily separated and distinguished from the matrix and other particles by atom number contrast using comparisons of the backscatter electrons (BSE) images and the secondary electrons (SE......) images in scanning electron microscope (SEM). The smaller Laves phase particle size results in higher creep strength and longer creep exposure time at the same conditions. DICTRA software was used to model the growth and coarsening behavior of Laves phase in the three P92 steels. Good agreements were...... attained between measurements in SEM and modeling by DICTRA. Ostwald ripening should be used for the coarsening calculation of Laves phase in P92 steels for time longer than 20000 h and 50000 h at 650°C and 600°C, respectively. © 2010 Chin. Soc. for Elec. Eng....

  5. Parafibromin inhibits cancer cell growth and causes G1 phase arrest

    International Nuclear Information System (INIS)

    Zhang Chun; Kong Dong; Tan, M.-H.; Pappas, Donald L.; Wang, P.-F.; Chen, Jindong; Farber, Leslie; Zhang Nian; Koo, H.-M.; Weinreich, Michael; Williams, Bart O.; Teh, B.T.

    2006-01-01

    The HRPT2 (hereditary hyperparathyroidism type 2) tumor suppressor gene encodes a ubiquitously expressed 531 amino acid protein termed parafibromin. Inactivation of parafibromin predisposes one to the development of HPT-JT syndrome. To date, the role of parafibromin in tumorigenesis is largely unknown. Here, we report that parafibromin is a nuclear protein that possesses anti-proliferative properties. We show that overexpression of parafibromin inhibits colony formation and cellular proliferation, and induces cell cycle arrest in the G1 phase. Moreover, HPT-JT syndrome-derived mutations in HRPT2 behave in a dominant-negative manner by abolishing the ability of parafibromin to suppress cell proliferation. These findings suggest that parafibromin has a critical role in cell growth, and mutations in HRPT2 can directly inhibit this role

  6. Effects of Phytoplankton Growth Phase on Delayed Settling Behavior of Marine Snow Aggregates at Sharp Density Transitions

    Science.gov (United States)

    Proctor, K. W.; Montgomery, Q. W.; Prairie, J. C.

    2016-02-01

    Marine snow aggregates play a fundamental role in the marine carbon cycle. Since marine snow aggregates are larger and thus sink faster than individual phytoplankton, aggregates often dominate carbon flux. Previous studies have shown that marine snow aggregates will significantly decrease their settling velocity when passing through sharp density transitions within the ocean, a phenomenon defined as delayed settling. Given the importance of aggregate settling to carbon export, these small-scale changes in aggregate settling dynamics may have significant impacts on the efficiency of the biological pump. However, there is still a lack of knowledge about how different physical properties of aggregates can affect this delayed settling. In this study, we investigated the effect of phytoplankton growth phase on delayed settling behavior. Using phytoplankton cultures stopped at four different growth phases, we formed marine snow aggregates in the laboratory in rotating cylindrical tanks. We then observed individual aggregates as they settled through a stratified tank. We will present data which illustrates that aggregates experience greatly reduced settling rates when passing through sharp density gradients and that the growth phase of the phytoplankton used to form these aggregates has a significant effect on this delayed settling behavior. A thorough understanding of the impact of phytoplankton growth phase on the delayed settling behavior of marine snow will offer insight into the way phytoplankton growth phase may influence the efficiency of the biological pump, carbon flux, and the carbon cycle as a whole.

  7. A model for growth of beta-phase particles in zirconium-2.5 wt percent niobium

    International Nuclear Information System (INIS)

    Chow, C.K.; Liner, Y.; Rigby, G.L.

    1984-08-01

    The kinetics of the α → β phase change in Zr-2.5 percent Nb pressure-tube material at constant temperature have been studied. The volume-fraction change of the β phase due to diffusion in an infinite α-phase matrix was considered, and a mathematical model with a numerical solution was developed to predict the transient spherical growth of the β-phase region. This model has been applied to Zr-2.5 wt percent Nb, and the calculated results compared to experiment

  8. Microbiological evaluation of a new growth-based approach for rapid detection of methicillin-resistant Staphylococcus aureus

    NARCIS (Netherlands)

    von Eiff, Christof; Maas, Dominik; Sander, Gunnar; Friedrich, Alexander W; Peters, Georg; Becker, Karsten

    OBJECTIVES: Recently, a rapid screening tool for methicillin-resistant Staphylococcus aureus (MRSA) has been introduced that applies a novel detection technology allowing the rapid presence or absence of MRSA to be determined from an enrichment broth after only a few hours of incubation. To evaluate

  9. Plant and Floret Growth at Distinct Developmental Stages During the Stem Elongation Phase in Wheat

    Directory of Open Access Journals (Sweden)

    Zifeng Guo

    2018-03-01

    Full Text Available Floret development is critical for grain setting in wheat (Triticum aestivum, but more than 50% of grain yield potential (based on the maximum number of floret primordia is lost during the stem elongation phase (SEP, from the terminal spikelet stage to anthesis. Dynamic plant (e.g., leaf area, plant height and floret (e.g., anther and ovary size growth and its connection with grain yield traits (e.g., grain number and width are not clearly understood. In this study, for the first time, we dissected the SEP into seven stages to investigate plant (first experiment and floret (second experiment growth in greenhouse- and field-grown wheat. In the first experiment, the values of various plant growth trait indices at different stages were generally consistent between field and greenhouse and were independent of the environment. However, at specific stages, some traits significantly differed between the two environments. In the second experiment, phenotypic and genotypic similarity analysis revealed that grain number and size corresponded closely to ovary size at anthesis, suggesting that ovary size is strongly associated with grain number and size. Moreover, principal component analysis (PCA showed that the top six principal components PCs explained 99.13, 98.61, 98.41, 98.35, and 97.93% of the total phenotypic variation at the green anther, yellow anther, tipping, heading, and anthesis stages, respectively. The cumulative variance explained by the first PC decreased with floret growth, with the highest value detected at the green anther stage (88.8% and the lowest at the anthesis (50.09%. Finally, ovary size at anthesis was greater in wheat accessions with early release years than in accessions with late release years, and anther/ovary size shared closer connections with grain number/size traits at the late vs. early stages of floral development. Our findings shed light on the dynamic changes in plant and floret growth-related traits in wheat and the

  10. Preliminary morphological and morphometric study of rat cerebellum following sodium arsenite exposure during rapid brain growth (RBG) period

    International Nuclear Information System (INIS)

    Dhar, Pushpa; Mohari, Nivedita; Mehra, Raj D.

    2007-01-01

    The effects of arsenic exposure during rapid brain growth (RBG) period were studied in rat brains with emphasis on the Purkinje cells of the cerebellum. The RBG period in rats extends from postnatal day 4 (PND 4) to postnatal day 10 (PND 10) and is reported to be highly vulnerable to environmental insults. Mother reared Wistar rat pups were administered intraperitoneal injections (i.p.) of sodium arsenite (aqueous solution) in doses of 1.0, 1.5 and 2.0 mg/kg body weight (bw) to groups II, III and IV (n = 6 animals/group) from PND 4 to 10 (sub acute). Control animals (group I) received distilled water by the same route. On PND 11, the animals were perfusion fixed with 4% paraformaldehyde in 0.1 M phosphate buffer (PB) with pH 7.4. The cerebellum obtained from these animals was post-fixed and processed for paraffin embedding. Besides studying the morphological characteristics of Purkinje cells in cresyl violet (CV) stained paraffin sections (10 μm), morphometric analysis of Purkinje cells was carried out using Image Analysis System (Image Proplus software version 4.5) attached to Nikon Microphot-FX microscope. The results showed that on PND 11, the Purkinje cells were arranged in multiple layers extending from Purkinje cell layer (PL) to outer part of granule cell layer (GL) in experimental animals (contrary to monolayer arrangement within PL in control animals). Also, delayed maturation (well defined apical cytoplasmic cones and intense basal basophilia) was evident in Purkinje cells of experimental animals on PND 11. The mean Purkinje cell nuclear area was significantly increased in the arsenic treated animals compared to the control animals. The observations of the present study (faulty migration, delayed maturation and alteration in nuclear area measurements of Purkinje cells subsequent to arsenic exposure) thus provided the morphological evidence of structural alterations subsequent to arsenite induced developmental neurotoxicity which could be presumed to be

  11. Proteomic analysis of lactose-starved Lactobacillus casei during stationary growth phase.

    Science.gov (United States)

    Hussain, M A; Knight, M I; Britz, M L

    2009-03-01

    Starvation stress is a condition that nonstarter lactic acid bacteria (NSLAB) normally encounter. This study was aimed to investigate starvation-induced proteins in Lactobacillus casei during stationary growth phase. The impact of carbohydrate starvation on L. casei GCRL163 was investigated using two different media (a modified de Man, Rogosa and Sharpe broth and a semi-defined medium). Cells were grown in the presence of excess lactose (1%) or starvation (0%) and differences in the patterns of one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis and two-dimensional electrophoresis of the cytosolic protein fractions were investigated. Differentially regulated proteins were identified by MALDI-TOF/TOF mass spectrometry. Many differentially regulated proteins were enzymes of various metabolic pathways involved in carbohydrate metabolism to yield energy. Differences in protein expression were also observed in the two culture conditions tested in this experiment. Numerous glycolytic enzymes were differentially regulated under lactose starvation. The differential expression of these glycolytic enzymes suggests a potential survival strategy under harsh growth conditions (i.e. lactose starvation). This paper reports improved understanding of stress responses and survival mechanism of NSLAB under lactose-depleted cheese-ripening condition. This knowledge of how NSLAB bacteria adapt to lactose starvation could be applied to predict the performances of bacteria in other industrial applications.

  12. The effect of the phase composition of compound layer on the growth kinetics of the nitrided layer

    International Nuclear Information System (INIS)

    Ratajski, J.; Olik, R.; Suszko, T.; Tacikowski, J.

    2001-01-01

    This paper presents a part of research work on the kinetics of formation and growth of nitrided layers on 40HM steel that was conducted within the research project devoted to the control of gaseous nitriding processes. The purpose of the research was to find answers to still opened questions connected with the optimization of the growth kinetics of nitrided layer. It has been demonstrated in particular how important in diffusion layer kinetics of growth on steel is the role-played by compound layer phase composition. Mainly, this refers to designing changes of parameters in processes where accurate formation of layer on precise parts with required tolerance of size changes is demanded. It comes out of the presented research that proper diffusion layer growth kinetics can be achieved when phase ε dominates in the compound layer. This domination of the phase ε influences speed of growth of the compound layer and first of all growth of diffusion layer. The obtained results are also a starting point of for working-out of good functional relations which could create good basis for design of algorithms of potential values changes in the function of the process time which provides the optimal kinetics of the growth of the layers. In this respect it has been achieved very good qualitative relation between the simulated distribution of nitrogen concentration in the layer and experimentally established distribution of hardness. (author)

  13. Comprehensive modeling of solid phase epitaxial growth using Lattice Kinetic Monte Carlo

    International Nuclear Information System (INIS)

    Martin-Bragado, Ignacio

    2013-01-01

    Damage evolution of irradiated silicon is, and has been, a topic of interest for the last decades for its applications to the semiconductor industry. In particular, sometimes, the damage is heavy enough to collapse the lattice and to locally amorphize the silicon, while in other cases amorphization is introduced explicitly to improve other implanted profiles. Subsequent annealing of the implanted samples heals the amorphized regions through Solid Phase Epitaxial Regrowth (SPER). SPER is a complicated process. It is anisotropic, it generates defects in the recrystallized silicon, it has a different amorphous/crystalline (A/C) roughness for each orientation, leaving pits in Si(1 1 0), and in Si(1 1 1) it produces two modes of recrystallization with different rates. The recently developed code MMonCa has been used to introduce a physically-based comprehensive model using Lattice Kinetic Monte Carlo that explains all the above singularities of silicon SPER. The model operates by having, as building blocks, the silicon lattice microconfigurations and their four twins. It detects the local configurations, assigns microscopical growth rates, and reconstructs the positions of the lattice locally with one of those building blocks. The overall results reproduce the (a) anisotropy as a result of the different growth rates, (b) localization of SPER induced defects, (c) roughness trends of the A/C interface, (d) pits on Si(1 1 0) regrown surfaces, and (e) bimodal Si(1 1 1) growth. It also provides physical insights of the nature and shape of deposited defects and how they assist in the occurrence of all the above effects

  14. Proteomic Analysis of Bacillus thuringiensis Strain 4.0718 at Different Growth Phases

    Directory of Open Access Journals (Sweden)

    Xiaohui Li

    2012-01-01

    Full Text Available The growth process of Bacillus thuringiensis Bt4.0718 strain was studied using proteomic technologies. The proteins of Bt whole cells at three phases—middle vegetative, early sporulation, and late sporulation—were extracted with lysis buffer, followed with separation by 2-DE and identified by MALDI-TOF/TOF MS. Bioactive factors such as insecticidal crystal proteins (ICPs including Cry1Ac(3, Cry2Aa, and BTRX28, immune inhibitor (InhA, and InhA precursor were identified. InhA started to express at the middle vegetative phase, suggesting its contribution to the survival of Bt in the host body. At the early sporulation phase, ICPs started their expression. CotJC, OppA, ORF1, and SpoIVA related to the formation of crystals and spores were identified, the expression characteristics of which ensured the stable formation of crystals and spores. This study provides an important foundation for further exploration of the stable expression of ICPs, the smooth formation of crystals, and the construction of recombinant strains.

  15. Predicting the growth of S i3N4 nanowires by phase-equilibrium-dominated vapor-liquid-solid mechanism

    Science.gov (United States)

    Zhang, Yongliang; Cai, Jing; Yang, Lijun; Wu, Qiang; Wang, Xizhang; Hu, Zheng

    2017-09-01

    Nanomaterial synthesis is experiencing a profound evolution from empirical science ("cook-and-look") to prediction and design, which depends on the deep insight into the growth mechanism. Herein, we report a generalized prediction of the growth of S i3N4 nanowires by nitriding F e28S i72 alloy particles across different phase regions based on our finding of the phase-equilibrium-dominated vapor-liquid-solid (PED-VLS) mechanism. All the predictions about the growth of S i3N4 nanowires, and the associated evolutions of lattice parameters and geometries of the coexisting Fe -Si alloy phases, are experimentally confirmed quantitatively. This progress corroborates the general validity of the PED-VLS mechanism, which could be applied to the design and controllable synthesis of various one-dimensional nanomaterials.

  16. High growth and rapid internationalisation of firms from emerging markets: the case of the Middle East and North Africa (MENA) Region

    OpenAIRE

    Hatem, Omaima

    2012-01-01

    The aim of this thesis is to understand the phenomena of the high growth and rapid internationalisation of firms from emerging markets. It explores the applicability of international entrepreneurship theory to the context of the emerging market enterprises in the Middle East and North Africa (MENA) region. It integrates the literature of strategic entrepreneurship and that of portfolio entrepreneurship with the literature of international entrepreneurship to provide a closer fi...

  17. Phenotypic diversity of diploid and haploid Emiliania huxleyi cells and of cells in different growth phases revealed by comparative metabolomics.

    Science.gov (United States)

    Mausz, Michaela A; Pohnert, Georg

    2015-01-01

    In phytoplankton a high species diversity of microalgae co-exists at a given time. But diversity is not only reflected by the species composition. Within these species different life phases as well as different metabolic states can cause additional diversity. One important example is the coccolithophore Emiliania huxleyi. Diploid cells play an important role in marine ecosystems since they can form massively abundant algal blooms but in addition the less abundant haploid life phase of E. huxleyi occurs in lower quantities. Both life phases may fulfill different functions in the plankton. We hypothesize that in addition to the functional diversity caused by this life phase transition the growth stage of cells can also influence the metabolic composition and thus the ecological impact of E. huxleyi. Here we introduce a metabolomic survey in dependence of life phases as well as different growth phases to reveal such changes. The comparative metabolomic approach is based on the extraction of intracellular metabolites from intact microalgae, derivatization and analysis by gas chromatography coupled to mass spectrometry (GC-MS). Automated data processing and statistical analysis using canonical analysis of principal coordinates (CAP) revealed unique metabolic profiles for each life phase. Concerning the correlations of metabolites to growth phases, complex patterns were observed. As for example the saccharide mannitol showed its highest concentration in the exponential phase, whereas fatty acids were correlated to stationary and sterols to declining phase. These results are indicative for specific ecological roles of these stages of E. huxleyi and are discussed in the context of previous physiological and ecological studies. Copyright © 2014 Elsevier GmbH. All rights reserved.

  18. Quantitative Phase-Field Approach for Simulating Grain Growth in Anisotropic Systems with Arbitrary Inclination and Misorientation Dependence

    International Nuclear Information System (INIS)

    Moelans, N.; Blanpain, B.; Wollants, P.

    2008-01-01

    A phase-field approach for quantitative simulations of grain growth in anisotropic systems is introduced, together with a new methodology to derive appropriate model parameters that reproduce given misorientation and inclination dependent grain boundary energy and mobility in the simulations. The proposed model formulation and parameter choice guarantee a constant diffuse interface width and consequently give high controllability of the accuracy in grain growth simulations

  19. Effect of component substitution on the magnetic properties of Zr2Co11 phase and rapidly quenched Zr2Co11 - based alloys

    International Nuclear Information System (INIS)

    Gabaj, A.M.; Shchegoleva, N.N.; Gaviko, V.S.; Ivanova, G.V.

    2003-01-01

    Magnetic properties of homogenized ingots and rapidly quenched ribbons of (Zr 1-x M x ) 16.4 Co 83.6 with M=Ti, Nb, Y, Gd and Zr 16.4 (Co 1-y M* y ) 83.6 with M*= Mn, Fe, Ni, Cu, Al, Ga, Si are studied. The phase composition of the alloys is determined with the help of thermomagnetic analysis and, in specific cases, with the use of X-ray diffraction analysis and electron microscopical data. It is ascertained that a part of zirconium in a phase Zr 2 Co 11 can be replaced by titanium and niobium. The solubility of rare earth elements is noted to be not revealed. Cobalt is partially replaced by Al, Cu, Ga, Si, Ni and Fe in a 2:11 phase, and Mn stabilizes the structure of a Laves phase with unexpectedly strong ferromagnetic properties. For magnetic hardness of the rapidly quenched alloys the introduction of Ti is appeared to be most beneficial. This element enhances noticeably the coercive force and hysteresis loop rectangularity and, as it takes place, it does not change practically magnetic properties of a 2:11 phase but suppresses the formation of dendrites on its crystallization. A small increase of the coercive force is also observed on addition of Cu and Al [ru

  20. Rapid Separation of Copper Phase and Iron-Rich Phase From Copper Slag at Low Temperature in a Super-Gravity Field

    Science.gov (United States)

    Lan, Xi; Gao, Jintao; Huang, Zili; Guo, Zhancheng

    2018-06-01

    A novel approach for quickly separating a metal copper phase and iron-rich phase from copper slag at low temperature is proposed based on a super-gravity method. The morphology and mineral evolution of the copper slag with increasing temperature were studied using in situ high-temperature confocal laser scanning microscopy and ex situ scanning electron microscopy and X-ray diffraction methods. Fe3O4 particles dispersed among the copper slag were transformed into FeO by adding an appropriate amount of carbon as a reducing agent, forming the slag melt with SiO2 at low temperature and assisting separation of the copper phase from the slag. Consequently, in a super-gravity field, the metallic copper and copper matte were concentrated as the copper phase along the super-gravity direction, whereas the iron-rich slag migrated in the opposite direction and was quickly separated from the copper phase. Increasing the gravity coefficient (G) significantly enhanced the separation efficiency. After super-gravity separation at G = 1000 and 1473 K (1200 °C) for 3 minutes, the mass fraction of Cu in the separated copper phase reached 86.11 wt pct, while that in the separated iron-rich phase was reduced to 0.105 wt pct. The recovery ratio of Cu in the copper phase was as high as up to 97.47 pct.

  1. Rapid Economic Growth and Natural Gas Consumption Nexus: Looking forward from Perspective of 11th Malaysian Plan

    Science.gov (United States)

    Bekhet, H. A.; Yasmin, T.

    2016-03-01

    The present study investigates the relationship between economic growth and energy consumption by incorporating CO2 emissions, natural gas consumption and population in Malaysia. Annual data and F-bound test and granger causality have applied to test the existence of long run relationship between the series. The results show that variables are cointegrated for long run relationship. The results also indicate that natural gas consumption is an important contributing factor to energy demand and hence economic growth in case of Malaysia. The causality analysis highlights that the feedback hypothesis exists between economic growth and energy consumption. While, conservative hypothesis is validated between natural gas consumption and economic growth which implies that economic growth will push natural gas consumption policies in future. This study opens up new direction for policy makers to formulate a comprehensive natural gas policy to sustain environment for long span of time in case to achieve 11th MP targets.

  2. Liquid Phase Epitaxial Growth of Al-doped f-SiC for White Light-Emitting Diodes

    DEFF Research Database (Denmark)

    Tang, Kai; Ma, Xiang; can der Eijk, Casper

    efficiency, better light quality and longer lifespan, compared to the current yellow phosphor based white LEDs.Liquid phase epitaxy technology can yield a high crystalline quality in terms of structural perfection owing to the fact that it is a near equilibrium crystalline growth process. In addition....... The experimental results are presented and discussed. Since operational temperature of LPE growth is much lower than that currently used in physical vapour transport (PVT) process, it is expected to save the energy consumption for SiC crystal growth....

  3. Pb sub(1-x) Sn sub(x) Te monocrystal growth by vapor phase transport, with formation of a liquid/solid growth interphase

    International Nuclear Information System (INIS)

    An, C.Y.; Bandeira, I.N.

    1983-01-01

    Due to segregation effects single-crystals of Pb sub(1-x) Sn sub(x) Te growth by Bridgman techniques have an inhomogenous composition profile. A vapor phase transport growth process has been developed in order to reduce convective flows. This is due to the very thin melt layer in front of the crystal, that makes convective flows small and solute mixing in the melt very low. By this process single-crystals with 60 mm lenght by 15 mm diameter and a high degree of homogeneity have been grown. (Author) [pt

  4. Phase II trial of epidermal growth factor ointment for patients with Erlotinib-related skin effects.

    Science.gov (United States)

    Hwang, In Gyu; Kang, Jung Hun; Oh, Sung Yong; Lee, Suee; Kim, Sung-Hyun; Song, Ki-Hoon; Son, Choonhee; Park, Min Jae; Kang, Myung Hee; Kim, Hoon Gu; Lee, Jeeyun; Park, Young Suk; Sun, Jong Mu; Kim, Hyun Jung; Kim, Chan Kyu; Yi, Seong Yoon; Jang, Joung-Soon; Park, Keunchil; Kim, Hyo-Jin

    2016-01-01

    The efficacy of erlotinib, the epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, has been demonstrated in patients with non-small cell lung cancer (NSCLC) and pancreatic cancer (PC). In the present study, we evaluated the effect of epidermal growth factor (EGF) ointment on erlotinib-related skin effects (ERSEs). This was an open-label, non-comparative, multicenter, phase II trial. The patients included those diagnosed with NSCLC or PC who were treated with erlotinib. The effectiveness of the ointment was defined as follows: (1) grade 2, 3, or 4 ERSEs downgraded to ≤ grade 1 or (2) grade 3 or 4 ERSEs downgraded to grade 2 and persisted for at least 2 weeks. Fifty-two patients from seven institutes in Korea were enrolled with informed consent. The final assessment included 46 patients (30 males, 16 females). According to the definition of effectiveness, the EGF ointment was effective in 36 (69.2%) intention to treat patients. There were no statistically significant differences in the effectiveness of the EGF ointment by gender (p = 0.465), age (p = 0.547), tumor type (p = 0.085), erlotinib dosage (p = 0.117), and number of prior chemotherapy sessions (p = 0.547). The grading for the average National Cancer Institute's Common Terminology Criteria for Adverse Events (NCI-CTCAE) rating of rash/acne and itching improved from 2.02 ± 0.83 to 1.13 ± 0.89 and 1.52 ± 0.84 to 0.67 ± 0.90, respectively (p reason for discontinuing the study was progression of cancer (37%). Based on the results, the EGF ointment is effective for ERSEs, regardless of gender, age, type of tumor, and dosage of erlotinib. The EGF ointment evenly improved all kinds of symptoms of ERSEs. ClinicalTrials.gov identifier: NCT01593995.

  5. Growth-Phase-Specific Modulation of Cell Morphology and Gene Expression by an Archaeal Histone Protein.

    Science.gov (United States)

    Dulmage, Keely A; Todor, Horia; Schmid, Amy K

    2015-09-08

    In all three domains of life, organisms use nonspecific DNA-binding proteins to compact and organize the genome as well as to regulate transcription on a global scale. Histone is the primary eukaryotic nucleoprotein, and its evolutionary roots can be traced to the archaea. However, not all archaea use this protein as the primary DNA-packaging component, raising questions regarding the role of histones in archaeal chromatin function. Here, quantitative phenotyping, transcriptomic, and proteomic assays were performed on deletion and overexpression mutants of the sole histone protein of the hypersaline-adapted haloarchaeal model organism Halobacterium salinarum. This protein is highly conserved among all sequenced haloarchaeal species and maintains hallmark residues required for eukaryotic histone functions. Surprisingly, despite this conservation at the sequence level, unlike in other archaea or eukaryotes, H. salinarum histone is required to regulate cell shape but is not necessary for survival. Genome-wide expression changes in histone deletion strains were global, significant but subtle in terms of fold change, bidirectional, and growth phase dependent. Mass spectrometric proteomic identification of proteins from chromatin enrichments yielded levels of histone and putative nucleoid-associated proteins similar to those of transcription factors, consistent with an open and transcriptionally active genome. Taken together, these data suggest that histone in H. salinarum plays a minor role in DNA compaction but important roles in growth-phase-dependent gene expression and regulation of cell shape. Histone function in haloarchaea more closely resembles a regulator of gene expression than a chromatin-organizing protein like canonical eukaryotic histone. Histones comprise the major protein component of eukaryotic chromatin and are required for both genome packaging and global regulation of expression. The current paradigm maintains that archaea whose genes encode

  6. Phase-separation control of KxFe2-ySe2 superconductor through rapid-quenching process

    International Nuclear Information System (INIS)

    Yanagisawa, Yusuke; Tanaka, Masashi; Yamashita, Aichi; Suzuki, Kouji; Hara, Hiroshi; Takeya, Hiroyuki; Takano, Yoshihiko; ElMassalami, Mohammed

    2017-01-01

    K x Fe 2-y Se 2 exhibits iron-vacancy ordering at T s ∼ 270°C and separates into two phases: a minor superconducting (iron-vacancy-disordered) phase and a major non-superconducting (iron-vacancy-ordered) phase. The microstructural and superconducting properties of this intermixture can be tuned by an appropriate control of the quenching process through T s . A faster quenching rate leads to a finer microstructure and a suppression of formation of the non-superconducting phase by up to 50%. Nevertheless, such a faster cooling rate induces a monotonic reduction in the superconducting transition temperature (from 30.7 to 26.0 K) and, simultaneously, a decrease in the iron content within the superconducting phase such that the compositional ratio changed from K 0.35 Fe 1.83 Se 2 to K 0.58 Fe 1.71 Se 2 . (author)

  7. γ-U phase in U-Pt system retained to low temperatures by means of rapid cooling

    Energy Technology Data Exchange (ETDEWEB)

    Kim-Ngan, N.-T.H., E-mail: tarnawsk@up.krakow.pl [Institute of Physics, Pedagogical University, Podchorazych 2, 30 084 Kraków (Poland); Paukov, M. [Faculty of Mathematics and Physics, Charles University, Ke Karlovu 5, 12116 Prague (Czech Republic); Tarasenko, R. [Faculty of Mathematics and Physics, Charles University, Ke Karlovu 5, 12116 Prague (Czech Republic); Institute of Physics, Faculty of Science, P.J. Šafárik University, Park Angelinum 9, 04154 Košice (Slovakia); Tkáč, V.; Minarik, P.; Drozdenko, D.; Havela, L. [Faculty of Mathematics and Physics, Charles University, Ke Karlovu 5, 12116 Prague (Czech Republic)

    2016-10-15

    Splat-cooling technique with a cooling rate better than 10{sup 6} K/s helps to increase the Pt solubility in the (cubic) γ-U phase and retain such γ-U phase in U-15 at.% Pt splat down to low temperatures. The splat-cooled U-Pt alloys are very stable in exposing to air. The γ-U phase (U-15 at.% Pt splat) is characterized by a negative temperature coefficient of the resistivity (dρ/dT < 0). The splats become superconducting below 1.1 K. - Highlights: • γ-U phase stabilization in U-15 at.% Pt splat-cooled alloys. • Splat-cooling helps to increase the Pt solubility in cubic γ-U phase. • All U-Pt alloys (0–15 at.% Pt) become superconducting below 1.1 K.

  8. Effect of V-Nd co-doping on phase transformation and grain growth process of TiO2

    Science.gov (United States)

    Khatun, Nasima; Amin, Ruhul; Anita, Sen, Somaditya

    2018-05-01

    The pure and V-Nd co-doped TiO2 samples are prepared by the modified sol-gel process. The phase formation is confirmed by XRD spectrum. Phase transformation is delayed in V-Nd co-doped TiO2 (TVN) samples compared to pure TiO2. The particle size is comparatively small in TVN samples at both the temperature 450 °C and 900 °C. Hence the effect of Nd doping is dominated over V doping in both phase transformation and grain growth process of TiO2.

  9. Growth

    Science.gov (United States)

    John R. Jones; George A. Schier

    1985-01-01

    This chapter considers aspen growth as a process, and discusses some characteristics of the growth and development of trees and stands. For the most part, factors affecting growth are discussed elsewhere, particularly in the GENETICS AND VARIATION chapter and in chapters in PART 11. ECOLOGY. Aspen growth as it relates to wood production is examined in the WOOD RESOURCE...

  10. Growth-Phase Sterigmatocystin Formation on Lactose Is Mediated via Low Specific Growth Rates in Aspergillus nidulans

    Directory of Open Access Journals (Sweden)

    Zoltán Németh

    2016-11-01

    Full Text Available Seed contamination with polyketide mycotoxins such as sterigmatocystin (ST produced by Aspergilli is a worldwide issue. The ST biosynthetic pathway is well-characterized in A. nidulans, but regulatory aspects related to the carbon source are still enigmatic. This is particularly true for lactose, inasmuch as some ST production mutant strains still synthesize ST on lactose but not on other carbon substrates. Here, kinetic data revealed that on d-glucose, ST forms only after the sugar is depleted from the medium, while on lactose, ST appears when most of the carbon source is still available. Biomass-specified ST production on lactose was significantly higher than on d-glucose, suggesting that ST formation may either be mediated by a carbon catabolite regulatory mechanism, or induced by low specific growth rates attainable on lactose. These hypotheses were tested by d-glucose limited chemostat-type continuous fermentations. No ST formed at a high growth rate, while a low growth rate led to the formation of 0.4 mg·L−1 ST. Similar results were obtained with a CreA mutant strain. We concluded that low specific growth rates may be the primary cause of mid-growth ST formation on lactose in A. nidulans, and that carbon utilization rates likely play a general regulatory role during biosynthesis.

  11. Computational thermodynamic investigations of growth and coarsening of laves phase precipitates in 12%Cr creep resistant steels

    Energy Technology Data Exchange (ETDEWEB)

    Prat, O.; Rojas, D. [Max-Planck-Institut fuer Eisenforschung GmbH, Duesseldorf (Germany); Garcia, J.; Kaysser-Pyzalla, A.R. [Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, Berlin (Germany); Bochum Univ. (Germany)

    2010-07-01

    Precipitation phenomena in 12%Cr high alloyed steels have been investigated at creep conditions of 650 and 150 MPa up to 6.500 hours in two different alloys. Growth and coarsening of Laves phase was determined experimentally by measuring the size of Laves phase on crept samples using scanning transmission electron microscopy (STEM). The simulations were performed using the software DICTRA based on the assumption the local equilibrium at the moving phase interface. For equilibrium calculations, the Thermo-Calc software was used. The experimental results were compared with DICTRA simulations, showing good agreement. Both the quantitative metallographic measurements as well as the simulations indicate very low coarsening for Laves Phase. The influence of different elements such as Co, Si and Cu on coarsening for Laves phase was simulated. (orig.)

  12. Production of Vibrio vulnificus metalloprotease VvpE begins during the early growth phase: usefulness of gelatin-zymography.

    Science.gov (United States)

    Kim, Choon-Mee; Kang, Sang-Mee; Jeon, Ho-Jong; Shin, Sung-Heui

    2007-07-01

    Recent studies have demonstrated that expression of the vvpE gene begins during the early growth phase albeit at low levels. However, we found that the traditional protease assay method that is used to measure caseinolytic activity in culture supernatants is not suitable for the measurement of extracellular VvpE that is produced at low levels during the early growth phase. By using gelatin-zymography in place of the protease assay, we could specifically detect only VvpE of several proteases produced by Vibrio vulnificus. Moreover, we could sensitively measure VvpE produced at low levels during the early growth phase, which was consistent with transcription of the vvpE gene. The extracellular production of VvpE was reduced or delayed by mutation of the pilD gene which encodes for the type IV leader peptidase/N-methyltransferase associated with the type II general secretion system; the delayed production of VvpE was recovered by in trans complementation of the wild-type pilD gene. These results indicate that VvpE begins to be produced during the early growth phase via the PilD-mediated type II general secretion system, and that the use of gelatin-zymography is recommended as a simple method for the sensitive and specific detection of VvpE production.

  13. Fundamental aspects of nucleation and growth in the solution-phase synthesis of germanium nanocrystals

    KAUST Repository

    Codoluto, Stephen C.

    2010-01-01

    Colloidal Ge nanocrystals (NCs) were synthesized via the solution phase reduction of germanium(ii) iodide. We report a systematic investigation of the nanocrystal nucleation and growth as a function of synthesis conditions including the nature of coordinating solvents, surface bound ligands, synthesis duration and temperature. NC synthesis in reaction environments with weakly bound phosphine surface ligand led to the coalescence of nascent particles leading to ensembles with broad lognormal particle diameter distributions. Synthesis in the presence of amine or alkene ligands mitigated particle coalescence. High-resolution transmission electron micrographs revealed that NCs grown in the presence of weak ligands had a high crystal defect density whereas NCs grown in amine solutions were predominantly defect-free. We applied infrared spectroscopy to study the NC surface chemistry and showed that alkene ligands project the NCs from surface oxidation. Photoluminescence spectroscopy measurements showed that alkene ligands passivate surface traps, as indicated by infrared fluorescence, conversely oxidized phosphine and amine passivated NCs did not fluoresce. © 2010 The Royal Society of Chemistry.

  14. Phase transformation and grain growth behavior of a nanocrystalline 18/8 stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Kotan, Hasan, E-mail: hasankotan@gmail.com [Konya Necmettin Erbakan University, Department of Metallurgical & Materials Engineering, Konya 42090 (Turkey); Darling, Kris A. [US Army Research Laboratory, Weapons and Materials Research Directorate, RDRL-WMM-F, Aberdeen Proving Ground, MD 21005-5069 (United States)

    2017-02-16

    Fe-18Cr-8Ni and Fe-18Cr-8Ni-1Y (at%) stainless steel powders were nanostructured by mechanical alloying from elemental powders and subjected to 90 min annealing treatments at various temperatures. The microstructural evolutions as a function of alloy compositions and temperatures were investigated by in-situ and ex-situ x-ray diffraction experiments, transmission electron microscopy and focused ion beam microscopy. The dependence of hardness on the microstructure was utilized to study the mechanical changes. It was found that the resulting microstructures by mechanical alloying were bcc solid solution, the so-called α’-martensite structure. The high temperature in-situ x-ray diffraction experiments showed that the martensite-to-austenite reverse phase transformation was completed above 800 and 900 °C for Fe-18Cr-8Ni and Fe-18Cr-8Ni-1Y steels, respectively. A partial or complete retransformation to martensite was observed upon cooling to room temperature. Annealing of nanocrystalline Fe-18Cr-8Ni steel yielded grain growth reaching to micron sizes at 1100 °C while addition of 1 at% yttrium stabilized the microstructure around 160 nm grain size and 6 GPa hardness after 90 min annealing at 1200 °C.

  15. Deviations from cooperative growth mode during eutectoid transformation: Insights from a phase-field approach

    International Nuclear Information System (INIS)

    Ankit, Kumar; Mukherjee, Rajdip; Mittnacht, Tobias; Nestler, Britta

    2014-01-01

    The non-cooperative eutectoid transformation relies on the presence of pre-existing cementite particles in the parent austenitic phase and yields a product, popularly known as the divorced eutectoid. Under isothermal conditions, two of the important parameters that influence the transformation mechanism and determine the final morphology are undercooling (below the A 1 temperature) and interparticle spacing. Although the criteria that govern the morphological transition from lamellar to divorced is experimentally well established, numerical studies giving a detailed exposition of the non-cooperative transformation mechanism have not been reported extensively. In the present work, we employ a multiphase-field model that uses thermodynamic information from the CALPHAD database to numerically simulate the pulling-away of the advancing ferrite–austenite interface from cementite, which results in a transition from lamellar to divorced eutectoid morphology in Fe–C alloy. We also identify the onset of a concurrent growth and coarsening regime at small interparticle spacing and low undercooling. We analyze the simulation results to unravel the essential physics behind this complex spatial and temporal evolution pathway and amend the existing criteria by constructing a Lamellar-Divorced-Coarsening (LDC) map

  16. Changes in Microbial Energy Metabolism Measured by Nanocalorimetry during Growth Phase Transitions

    Science.gov (United States)

    Robador, Alberto; LaRowe, Douglas E.; Finkel, Steven E.; Amend, Jan P.; Nealson, Kenneth H.

    2018-01-01

    Calorimetric measurements of the change in heat due to microbial metabolic activity convey information about the kinetics, as well as the thermodynamics, of all chemical reactions taking place in a cell. Calorimetric measurements of heat production made on bacterial cultures have recorded the energy yields of all co-occurring microbial metabolic reactions, but this is a complex, composite signal that is difficult to interpret. Here we show that nanocalorimetry can be used in combination with enumeration of viable cell counts, oxygen consumption rates, cellular protein content, and thermodynamic calculations to assess catabolic rates of an isolate of Shewanella oneidensis MR-1 and infer what fraction of the chemical energy is assimilated by the culture into biomass and what fraction is dissipated in the form of heat under different limiting conditions. In particular, our results demonstrate that catabolic rates are not necessarily coupled to rates of cell division, but rather, to physiological rearrangements of S. oneidensis MR-1 upon growth phase transitions. In addition, we conclude that the heat released by growing microorganisms can be measured in order to understand the physiochemical nature of the energy transformation and dissipation associated with microbial metabolic activity in conditions approaching those found in natural systems. PMID:29449836

  17. Metabolic flux analysis during the exponential growth phase of Saccharomyces cerevisiae in wine fermentations.

    Directory of Open Access Journals (Sweden)

    Manuel Quirós

    Full Text Available As a consequence of the increase in global average temperature, grapes with the adequate phenolic and aromatic maturity tend to be overripe by the time of harvest, resulting in increased sugar concentrations and imbalanced C/N ratios in fermenting musts. This fact sets obvious additional hurdles in the challenge of obtaining wines with reduced alcohols levels, a new trend in consumer demands. It would therefore be interesting to understand Saccharomyces cerevisiae physiology during the fermentation of must with these altered characteristics. The present study aims to determine the distribution of metabolic fluxes during the yeast exponential growth phase, when both carbon and nitrogen sources are in excess, using continuous cultures. Two different sugar concentrations were studied under two different winemaking temperature conditions. Although consumption and production rates for key metabolites were severely affected by the different experimental conditions studied, the general distribution of fluxes in central carbon metabolism was basically conserved in all cases. It was also observed that temperature and sugar concentration exerted a higher effect on the pentose phosphate pathway and glycerol formation than on glycolysis and ethanol production. Additionally, nitrogen uptake, both quantitatively and qualitatively, was strongly influenced by environmental conditions. This work provides the most complete stoichiometric model used for Metabolic Flux Analysis of S. cerevisiae in wine fermentations employed so far, including the synthesis and release of relevant aroma compounds and could be used in the design of optimal nitrogen supplementation of wine fermentations.

  18. Growth, structure and phase transitions of epitaxial nanowires of III-V semiconductors

    International Nuclear Information System (INIS)

    Glas, F; Patriarche, G; Harmand, J C

    2010-01-01

    We review and illustrate the impact of TEM on the study of nanowires of non-nitride III-V semiconductors, with particular emphasis on the understanding of the thermodynamics and kinetics of their formation assisted by nano-sized catalyst particles. Besides providing basic information about the morphology of the nanowires and their growth rate as a function of diameter, TEM offers insights into the peculiar crystalline structure that they adopt. We discuss the formation of the unusual wurtzite hexagonal crystalline phase and that of planar stacking defects in these nanowires and show that they are kinetically controlled. We also demonstrate the transformation of wurtzite into cubic sphalerite upon epitaxial burying of the nanowires. Nanowires are particularly interesting in that they allow the fabrication of precisely positioned quantum dots with well-defined geometries. In this respect, we discuss the formation of strained quantum-size inclusions in nanowires, their critical dimensions and the kinetic and thermodynamic factors governing the changes of the crystalline structure that sometimes occur around a hetero-interface.

  19. Growth of AlGaN under the conditions of significant gallium evaporation: phase separation and enhanced lateral growth

    OpenAIRE

    Mayboroda, I. O.; Knizhnik, A. A.; Grishchenko, Yu. V.; Ezubchenko, I. S.; Zanaveskin, Maxim L.; Presniakov, M. Yu.; Potapkin, B. V.; Ilyin, V. A.

    2017-01-01

    Growth kinetics of AlGaN in NH3 MBE under significant Ga desorption was studied. It was found that the addition of gallium stimulates 2D growth and provides better morphology of films compared to pure AlN. The effect was experimentally observed at up to 98% desorption of the impinging gallium. We found that, under the conditions of significant thermal desorption, larger amounts of gallium were retained at lateral boundaries of 3D surface features than at flat terraces because of the higher bi...

  20. Effect of second phase particles topology on the onset temperature of abnormal grain growth in Fe - 3%Si steels

    Directory of Open Access Journals (Sweden)

    Stoyka, V.

    2008-01-01

    Full Text Available The relations between regimes of dynamic annealing, state of secondary particles system and the onset temperature of abnormal grain growth are investigated. Two distinguish types of Fe-3%Si grain-oriented steels, after one and two stage cold rolling, were studied. The second phase particles remain unaffected in first type of steel during the heat treatment. Vice versa, the increased density of second phases was observed after annealing in the second type of the investigated materials. It is shown that start/onset of abnormal grain growth strongly depends on both volume fraction of second phase particles and annealing temperature. Texture and magnetic properties of the investigated samples are investigated within the current study.

  1. Temperature Effect Study on Growth and Survival of Pathogenic Vibrio parahaemolyticus in Jinjiang Oyster (Crassostrea rivularis with Rapid Count Method

    Directory of Open Access Journals (Sweden)

    Yuan Wang

    2018-01-01

    Full Text Available The growth of Vibrio parahaemolyticus (V. parahaemolyticus in oysters during postharvest storage increases the possibility of its infection in humans. In this work, to investigate the growth or survival profiles in different media, pathogenic V. parahaemolyticus in APW, Jinjiang oyster (JO, Crassostrea rivularis slurry, and live JO were studied under different temperatures. All the strain populations were counted through our double-layer agar plate (DLAP method. In APW, the pathogenic V. parahaemolyticus showed continuous growth under 15, 25, and 35°C, while a decline in behavior was displayed under 5°C. The similar survival trend of pathogenic V. parahaemolyticus in JO slurry and live JO was observed under 5, 25, and 35°C, except the delayed growth or decline profile compared to APW. Under 15°C, they displayed decline and growth profile in JO slurry and live JO, respectively. These results indicate the different sensitivity of pathogenic V. parahaemolyticus in these matrices to temperature variation. Furthermore, nonpathogenic V. parahaemolyticus displayed little difference in survival profiles when inoculated in live JO under corresponding temperatures. The results indicate that inhibition or promotion effect could be regulated under different storage temperature for both pathogenic and nonpathogenic strains. Besides, the DLAP method showed the obvious quickness and efficiency during the bacteria count.

  2. Growth kinetics and mass transport mechanisms of GaN columns by selective area metal organic vapor phase epitaxy

    Science.gov (United States)

    Wang, Xue; Hartmann, Jana; Mandl, Martin; Sadat Mohajerani, Matin; Wehmann, Hergo-H.; Strassburg, Martin; Waag, Andreas

    2014-04-01

    Three-dimensional GaN columns recently have attracted a lot of attention as the potential basis for core-shell light emitting diodes for future solid state lighting. In this study, the fundamental insights into growth kinetics and mass transport mechanisms of N-polar GaN columns during selective area metal organic vapor phase epitaxy on patterned SiOx/sapphire templates are systematically investigated using various pitch of apertures, growth time, and silane flow. Species impingement fluxes on the top surface of columns Jtop and on their sidewall Jsw, as well as, the diffusion flux from the substrate Jsub contribute to the growth of the GaN columns. The vertical and lateral growth rates devoted by Jtop, Jsw and Jsub are estimated quantitatively. The diffusion length of species on the SiOx mask surface λsub as well as on the sidewall surfaces of the 3D columns λsw are determined. The influences of silane on the growth kinetics are discussed. A growth model is developed for this selective area metal organic vapor phase epitaxy processing.

  3. Study of Morphological, Phenological and Variation of Fruit Traits During Berry Growth Phases of QzlouzumGrapevine Cultivar

    Directory of Open Access Journals (Sweden)

    Hamed Doulati Baneh

    2017-02-01

    quantitative traits, TSS (total soluble solids, TA (titrable acidity, pH, berry weight and diameter, seed length and weight from the beginning of the berry formation to harvest time of clusters in 15-day interval were measured. Results and discussion: The results of this study showed that flowers of Qzlouzum are female with reflexed stamens. The results also determined that none of pollens germinated on both liquid and solid media culture. Based on reflexed stamens and none pollen germination, Qzlouzum grape cultivar proves to be male sterile (physiological substance. This cultivar needs 1483 degree days (above 10°C from bud break till ripening. The changes in TA and TSS were reversed. Amount of acid reduced and sugar content increased with time and berry development. Veraision period was approximately started 55 days after full bloom. At this stage, which is also known as berry softening, acid concentration is reduced and the amount of sugar was increased. Acid content and pH of the fruit were opposite together and by reducing the amount of acid, the pH levels increased. Several studies have confirmed that after changing the color of the grape varieties,sugar can often increase. Conversely, acid reduction in berries is the first happensbefore color change in berries. The berry weight and size changes were described as Double Sigmoid Curve. In the first phase, berry diameter and weight increased rapidly and lasted 60 days. In the second phase or delay phase, berry weight and diameter changedvery slowly while seed weight reached themaximum in this stage. After this phase, the third phase which was associated began with veraision, sugar content increased and the amount of aciddecreased. At this stage berry reached its maximum size and weight. Conclusion: Uniform planting of Qzlouzum red grapes is not recommended because of male sterility and suitable pollinizers should be used. Male sterility, without emasculation will be suitable for grape breeding programs. In areas with

  4. Paraneoplastic precocious puberty and excessively rapid somatic growth associated with pediatric malignant hepatic tumor: 1 report of 2 cases

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ok Hwa; Bahk, Yong Whee [Cathalic University College of Medicine, Seoul (Korea, Republic of)

    1990-04-15

    Sexual precocity in a 28-months-old boy and markedly accelerated skeletal growth with large body in a 5 years and 5 months-old-girl are reported. The former resulted from human chorionic gonadotropin-producing hepatoblastoma and the latter from cerebral gigantism associated with hepatoma. These two different disorders are discussed on the common basis of rare association of malignant hepatic tumors with precocious sexual and / or somatic growth. The clinical manifestations, chemical abnormalities, and the radiologic findings are presented with a brief review of the literature.

  5. Paraneoplastic precocious puberty and excessively rapid somatic growth associated with pediatric malignant hepatic tumor: 1 report of 2 cases

    International Nuclear Information System (INIS)

    Kim, Ok Hwa; Bahk, Yong Whee

    1990-01-01

    Sexual precocity in a 28-months-old boy and markedly accelerated skeletal growth with large body in a 5 years and 5 months-old-girl are reported. The former resulted from human chorionic gonadotropin-producing hepatoblastoma and the latter from cerebral gigantism associated with hepatoma. These two different disorders are discussed on the common basis of rare association of malignant hepatic tumors with precocious sexual and / or somatic growth. The clinical manifestations, chemical abnormalities, and the radiologic findings are presented with a brief review of the literature

  6. A generalized-growth model to characterize the early ascending phase of infectious disease outbreaks

    DEFF Research Database (Denmark)

    Viboud, Cecile; Simonsen, Lone; Chowell, Gerardo

    2016-01-01

    the importance of sub-exponential growth for forecasting purposes.Results: We applied the generalized-growth model to 20 infectious disease outbreaks representing a range of transmission routes. We uncovered epidemic profiles ranging from very slow growth (p = 0.14 for the Ebola outbreak in Bomi, Liberia (2014...... African Ebola epidemic provided a unique opportunity to explore how growth profiles vary by geography; analysis of the largest district-level outbreaks revealed substantial growth variations (mean p = 0.59, range: 0.14–0.97). The districts of Margibi in Liberia and Bombali and Bo in Sierra Leone had near......-exponential growth, while the districts of Bomi in Liberia and Kenema in Sierra Leone displayed near constant incidences.Conclusions: Our findings reveal significant variation in epidemic growth patterns across different infectious disease outbreaks and highlights that sub-exponential growth is a common phenomenon...

  7. Silicon transport under rotating and combined magnetic fields in liquid phase diffusion growth of SiGe

    Energy Technology Data Exchange (ETDEWEB)

    Armour, N.; Dost, S. [Crystal Growth Laboratory, University of Victoria, Victoria, BC, V8W 3P6 (Canada)

    2010-04-15

    The effect of applied rotating and combined (rotating and static) magnetic fields on silicon transport during the liquid phase diffusion growth of SiGe was experimentally studied. 72-hour growth periods produced some single crystal sections. Single and polycrystalline sections of the processed samples were examined for silicon composition. Results show that the application of a rotating magnetic field enhances silicon transport in the melt. It also has a slight positive effect on flattening the initial growth interface. For comparison, growth experiments were also conducted under combined (rotating and static) magnetic fields. The processed samples revealed that the addition of static field altered the thermal characteristics of the system significantly and led to a complete melt back of the germanium seed. Silicon transport in the melt was also enhanced under combined fields compared with experiments with no magnetic field. (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  8. Effect of a static magnetic field on silicon transport in liquid phase diffusion growth of SiGe

    Energy Technology Data Exchange (ETDEWEB)

    Armour, N.; Dost, S. [Crystal Growth Laboratory, University of Victoria, Victoria, BC V8W 3P6 (Canada)

    2010-03-15

    Liquid phase diffusion experiments have been performed without and with the application of a 0.4 T static magnetic field using a three-zone DC furnace system. SiGe crystals were grown from the germanium side for a period of 72 h. Experiments have led to the growth of single crystal sections varying from 0 to 10 mm thicknesses. Examination of the processed samples (single and polycrystalline sections) has shown that the effect of the applied static magnetic field is significant. It alters the temperature distribution in the system, reduces mass transport in the melt, and leads to a much lower growth rate. The initial curved growth interface was slightly flattened under the effect of magnetic field. There were no growth striations in the single crystal sections of the samples. (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  9. Phase composition, structure and magnetic behaviour of low neodymium rapid-quenched Nd-Fe-B alloys

    Czech Academy of Sciences Publication Activity Database

    Ćosović, V.; Žák, Tomáš; Talijan, N.; Grujić, A.; Stajić-Trošić, J.

    2008-01-01

    Roč. 456, 1-2 (2008), s. 251-256 ISSN 0925-8388 R&D Projects: GA MŠk 1M0512 Institutional research plan: CEZ:AV0Z20410507 Keywords : multiphase Nd(Pr)-Fe-B alloys * rapid solidification * magnetic measurements * Mossbauer spectroscopy * X-ray diffraction * Nanocrystalline composite Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.510, year: 2008

  10. Rapid washing of filter paper discs in a solid-phase radioimmunoassay with a constant flow washing device

    International Nuclear Information System (INIS)

    Kemeny, D.M.; West, F.B.

    1982-01-01

    A machine has been developed for the rapid washing of the cellulose filter paper discs that are used in a number of radioimmunoassays. The machine is simple in design, easy to use, and is capable of washing 96 filter paper discs simultaneously. The efficiency of the machine is demonstrated by a RAST assay for measuring IgE antibodies to the venom. Time taken to wash the discs was reduced 3-fold without loss of sensitivity or reproducibility. (Auth.)

  11. Growth hormone preferentially induces the rapid, transient expression of SOCS-3, a novel inhibitor of cytokine receptor signaling

    DEFF Research Database (Denmark)

    Adams, T E; Hansen, J A; Starr, R

    1998-01-01

    Four members (SOCS-1, SOCS-2, SOCS-3, and CIS) of a family of cytokine-inducible, negative regulators of cytokine receptor signaling have recently been identified. To address whether any of these genes are induced in response to growth hormone (GH), serum-starved 3T3-F442A fibroblasts were incuba...

  12. Rapid quantification of viable Legionella in nuclear cooling tower waters using filter cultivation, fluorescent in situ hybridization and solid-phase cytometry.

    Science.gov (United States)

    Baudart, J; Guillaume, C; Mercier, A; Lebaron, P; Binet, M

    2015-05-01

    To develop a rapid and sensitive method to quantify viable Legionella spp. in cooling tower water samples. A rapid, culture-based method capable of quantifying as few as 600 Legionella microcolonies per litre within 2 days in industrial waters was developed. The method combines a short cultivation step of microcolonies on GVPC agar plate, specific detection of Legionella cells by a fluorescent in situ hybridization (FISH) approach, and a sensitive enumeration using a solid-phase cytometer. Following optimization of the cultivation conditions, the qualitative and quantitative performance of the method was assessed and the method was applied to 262 nuclear power plant cooling water samples. The performance of this method was in accordance with the culture method (NF-T 90-431) for Legionella enumeration. The rapid detection of viable Legionella in water is a major concern to the effective monitoring of this pathogenic bacterium in the main water sources involved in the transmission of legionellosis infection (Legionnaires' disease). The new method proposed here appears to be a robust, efficient and innovative means for rapidly quantifying cultivable Legionella in cooling tower water samples within 48 h. © 2015 The Society for Applied Microbiology.

  13. Liquid Phase Separation and the Aging Effect on Mechanical and Electrical Properties of Laser Rapidly Solidified Cu100−xCrx Alloys

    Directory of Open Access Journals (Sweden)

    Song-Hua Si

    2015-11-01

    Full Text Available Duplex structure Cu-Cr alloys are widely used as contact materials. They are generally designed by increasing the Cr content for the hardness improvement, which, however, leads to the unfavorable rapid increase of the electrical resistivity. The solidification behavior of Cu100−xCrx (x = 4.2, 25 and 50 in wt.% alloys prepared by laser rapid solidification is studied here, and their hardness and electrical conductivity after aging are measured. The results show that the Cu-4.2%Cr alloy has the most desirable combination of hardness and conductive properties after aging in comparison with Cu-25%Cr and Cu-50%Cr alloys. Very importantly, a 50% improvement in hardness is achieved with a simultaneous 70% reduction in electrical resistivity. The reason is mainly attributed to the liquid phase separation occurring in the Cu-4.2%Cr alloy, which introduces a large a

  14. A rapid monitoring method for inorganic arsenic in rice flour using reversed phase-high performance liquid chromatography-inductively coupled plasma mass spectrometry.

    Science.gov (United States)

    Narukawa, Tomohiro; Chiba, Koichi; Sinaviwat, Savarin; Feldmann, Jörg

    2017-01-06

    A new rapid monitoring method by means of high performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICP-MS) following the heat-assisted extraction was developed for measurement of total inorganic arsenic species in rice flour. As(III) and As(V) eluted at the same retention time and completely separated from organoarsenic species by an isocratic elution program on a reversed phase column. Therefore, neither ambiguous oxidation of arsenite to arsenate nor the integration of two peaks were necessary to determine directly the target analyte inorganic arsenic. Rapid injection allowed measuring 3 replicates within 6min and this combined with a quantitative extraction of all arsenic species from rice flour by a 15min HNO 3 -H 2 O 2 extraction makes this the fastest laboratory based method for inorganic arsenic in rice flour. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. A multiscale coupled finite-element and phase-field framework to modeling stressed grain growth in polycrystalline thin films

    Energy Technology Data Exchange (ETDEWEB)

    Jamshidian, M., E-mail: jamshidian@cc.iut.ac.ir [Department of Mechanical Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Institute of Structural Mechanics, Bauhaus-University Weimar, Marienstrasse 15, 99423 Weimar (Germany); Thamburaja, P., E-mail: prakash.thamburaja@gmail.com [Department of Mechanical & Materials Engineering, Universiti Kebangsaan Malaysia (UKM), Bangi 43600 (Malaysia); Rabczuk, T., E-mail: timon.rabczuk@tdt.edu.vn [Division of Computational Mechanics, Ton Duc Thang University, Ho Chi Minh City (Viet Nam); Faculty of Civil Engineering, Ton Duc Thang University, Ho Chi Minh City (Viet Nam)

    2016-12-15

    A previously-developed finite-deformation- and crystal-elasticity-based constitutive theory for stressed grain growth in cubic polycrystalline bodies has been augmented to include a description of excess surface energy and grain-growth stagnation mechanisms through the use of surface effect state variables in a thermodynamically-consistent manner. The constitutive theory was also implemented into a multiscale coupled finite-element and phase-field computational framework. With the material parameters in the constitutive theory suitably calibrated, our three-dimensional numerical simulations show that the constitutive model is able to accurately predict the experimentally-determined evolution of crystallographic texture and grain size statistics in polycrystalline copper thin films deposited on polyimide substrate and annealed at high-homologous temperatures. In particular, our numerical analyses show that the broad texture transition observed in the annealing experiments of polycrystalline thin films is caused by grain growth stagnation mechanisms. - Graphical abstract: - Highlights: • Developing a theory for stressed grain growth in polycrystalline thin films. • Implementation into a multiscale coupled finite-element and phase-field framework. • Quantitative reproduction of the experimental grain growth data by simulations. • Revealing the cause of texture transition to be due to the stagnation mechanisms.

  16. Structure of the gene encoding VGF, a nervous system-specific mRNA that is rapidly and selectively induced by nerve growth factor in PC12 cells.

    Science.gov (United States)

    Salton, S R; Fischberg, D J; Dong, K W

    1991-05-01

    Nerve growth factor (NGF) plays a critical role in the development and survival of neurons in the peripheral nervous system. Following treatment with NGF but not epidermal growth factor, rat pheochromocytoma (PC12) cells undergo neural differentiation. We have cloned a nervous system-specific mRNA, NGF33.1, that is rapidly and relatively selectively induced by treatment of PC12 cells with NGF and basic fibroblast growth factor in comparison with epidermal growth factor. Analysis of the nucleic acid and predicted amino acid sequences of the NGF33.1 cDNA clone suggested that this clone corresponded to the NGF-inducible mRNA called VGF (A. Levi, J. D. Eldridge, and B. M. Paterson, Science 229:393-395, 1985; R. Possenti, J. D. Eldridge, B. M. Paterson, A. Grasso, and A. Levi, EMBO J. 8:2217-2223, 1989). We have used the NGF33.1 cDNA clone to isolate and characterize the VGF gene, and in this paper we report the complete sequence of the VGF gene, including 853 bases of 5' flank revealed TATAA and CCAAT elements, several GC boxes, and a consensus cyclic AMP response element-binding protein binding site. The VGF promoter contains sequences homologous to other NGF-inducible, neuronal promoters. We further show that VGF mRNA is induced in PC12 cells to a greater extent by depolarization and by phorbol-12-myristate-13-acetate treatment than by 8-bromo-cyclic AMP treatment. By Northern (RNA) and RNase protection analysis, VGF mRNA is detectable in embryonic and postnatal central and peripheral nervous tissues but not in a number of nonneural tissues. In the cascade of events which ultimately leads to the neural differentiation of NGF-treated PC12 cells, the VGF gene encodes the most rapidly and selectively regulated, nervous-system specific mRNA yet identified.

  17. Diagnosis and laparoscopic management of a rare endometriosis-related peritoneal mass with rapid growth in early pregnancy.

    Science.gov (United States)

    Di Donato, Nadine; Facchini, Chiara; Leggieri, Concetta; Caprara, Giacomo; Seracchioli, Renato

    2015-08-01

    Herein is described the diagnosis, clinical management and laparoscopic removal of a rapid growing retro-uterine mass in a pregnant woman. After laparoscopic removal of the pelvic mass, diagnosis of peritoneal endometriotic cyst was made on histology. The patient was asymptomatic and no history of endometriosis was reported. The laparoscopic management of the peritoneal mass was safe and effective and to our knowledge this is the first case report describing a decidualized endometriotic lesion in the absence of a pre-pregnancy endometriosis diagnosis. © 2015 The Authors Journal of Obstetrics and Gynaecology Research © 2015 Japan Society of Obstetrics and Gynecology.

  18. Immunological dynamics associated with rapid virological response during the early phase of type I interferon therapy in patients with chronic hepatitis C.

    Science.gov (United States)

    Lee, Jae-Won; Kim, Won; Kwon, Eun-Kyung; Kim, Yuri; Shin, Hyun Mu; Kim, Dong-Hyun; Min, Chan-Ki; Choi, Ji-Yeob; Lee, Won-Woo; Choi, Myung-Sik; Kim, Byeong Gwan; Cho, Nam-Hyuk

    2017-01-01

    Type I interferons (IFNs) play an important role in antiviral immunity as well as immunopathogenesis of diverse chronic viral infections. However, the precise mechanisms regulating the multifaceted effects of type I IFNs on the immune system and pathological inflammation still remain unclear. In order to assess the immunological dynamics associated with rapid viral clearance in chronic hepatitis C patients during the acute phase of type I IFN therapy, we analyzed multiple parameters of virological and immunological responses in a cohort of 59 Korean hepatitis C patients who received pegylated IFN-α and ribavirin (IFN/RBV). Most of the Korean patients had favorable alleles in the IFN-λ loci for responsiveness to IFN/RBV (i.e., C/C in rs12979860, T/T in rs8099917, and TT/TT in rs368234815). Rapid virological response (RVR) was determined mainly by the hepatitis C virus genotype. Among the cytokines analyzed, higher plasma levels of IL-17A and FGF were observed in non-RVR patients infected with viral genotype 1 and IP-10 was consistently elevated in RVR group infected with genotype 2 during the early phase of antiviral therapy. In addition, these three cytokines were correlated each other, suggesting a functional linkage of the cytokines in antiviral responses during IFN/RBV therapy. A low baseline frequencies of regulatory T cells and γδ T cells, but high level of group 2 innate lymphoid cells, in peripheral bloods were also significantly associated with the RVR group, implicating a potential role of the cellular immunity during the early phase of IFN/RBV therapy. Therefore, the immunological programs established by chronic hepatitis C and rapid disruption of the delicate balance by exogenous type I IFN might be associated with the subsequent virological outcomes in chronic hepatitis C patients.

  19. Social and environmental determinants of child health in Mongolia across years of rapid economic growth: 2000-2010.

    Science.gov (United States)

    Joshi, Nehal; Bolorhon, Bolormaa; Narula, Indermohan; Zhu, Shihua; Manaseki-Hollan, Semira

    2017-10-30

    To understand the effect of economic growth on health, we investigated the trend in socio-economic and regional determinants of child health in Mongolia. This Central Asian country had the fastest economic growth amongst low and middle-income countries (LMICs) from 2000 to 2010 and a healthcare system in transition. Data was from Mongolian multiple indicator cluster surveys (MICS) in 2000, 2005 and 2010. Child nutrition/growth was measured by height-for-age z-score (HAZ), weight-for-age z-score (WAZ), prevalence of stunted (HAZ economic and environmental health determinants on each outcome in each year; 2000, 2005 and 2010. T-tests were used to measure significant change in HAZ and WAZ over the decade. Overall, from 2000 to 2010, there was a significant improvement (p economic factors increased on both stunting and weight. In 2000, region was a significant determinant: children living in three provinces were significantly more likely to be stunted and less likely to be immunised than Ulaanbaatar, but this was not significant by 2010. By 2010, none of the factors were significant determinants of immunisation in children. In 2000, economic status had no effect on stunting (OR = 0.91; 95%CI:0.49,1.66), however by 2010, children in the poorest economic quintile were 4 times more likely to be stunted than the richest (OR = 0.24; 95% CI:0.13,0.45; p Economic growth in Mongolia from 2000 to 2010 resulted in an increase in the effect of social determinants of child health; whilst focused policy improved access to immunisation. Children with less educated mothers and lower household incomes should be targeted in interventions to reduce health inequity.

  20. Proteomic analysis of growth phase-dependent expression of Legionella pneumophila proteins which involves regulation of bacterial virulence traits.

    Directory of Open Access Journals (Sweden)

    Tsuyoshi Hayashi

    Full Text Available Legionella pneumophila, which is a causative pathogen of Legionnaires' disease, expresses its virulent traits in response to growth conditions. In particular, it is known to become virulent at a post-exponential phase in vitro culture. In this study, we performed a proteomic analysis of differences in expression between the exponential phase and post-exponential phase to identify candidates associated with L. pneumophila virulence using 2-Dimentional Fluorescence Difference Gel Electrophoresis (2D-DIGE combined with Matrix-Assisted Laser Desorption/Ionization-Mass Spectrometry (MALDI-TOF-MS. Of 68 identified proteins that significantly differed in expression between the two growth phases, 64 were up-regulated at a post-exponential phase. The up-regulated proteins included enzymes related to glycolysis, ketone body biogenesis and poly-3-hydroxybutyrate (PHB biogenesis, suggesting that L. pneumophila may utilize sugars and lipids as energy sources, when amino acids become scarce. Proteins related to motility (flagella components and twitching motility-associated proteins were also up-regulated, predicting that they enhance infectivity of the bacteria in host cells under certain conditions. Furthermore, 9 up-regulated proteins of unknown function were found. Two of them were identified as novel bacterial factors associated with hemolysis of sheep red blood cells (SRBCs. Another 2 were found to be translocated into macrophages via the Icm/Dot type IV secretion apparatus as effector candidates in a reporter assay with Bordetella pertussis adenylate cyclase. The study will be helpful for virulent analysis of L. pneumophila from the viewpoint of physiological or metabolic modulation dependent on growth phase.

  1. Abstracts of 4. International Workshop on Molecular Beam Epitaxy and Vapour Phase Epitaxy Growth Physics and Technology

    International Nuclear Information System (INIS)

    2001-01-01

    4. International Workshop on Molecular Beam Epitaxy and Vapour Phase Epitaxy Growth Physics and Technology is the periodically held forum for discussion the problems connected with manufacturing of different nanostructures (thin films, quantum wells, quantum dots) needed in microelectronics. Preparation of such materials with desirable optical, electrical and magnetic properties being determined by their chemical composition and crystal structure has been discussed in detail during the workshop sessions. Optimization of crystal growth methods such as VPE and MBE from the view point of obtained material properties has also been extensively discussed

  2. Diversity as valued and troubled: social identities and demographic categories in understandings of rapid urban growth in Vanuatu.

    Science.gov (United States)

    Widmer, Alexandra

    2013-01-01

    This paper deals with the simultaneous mainstreaming and diversification of ni-Vanuatu social categories associated with the ways in which population growth is understood as a possible crisis in both demographic knowledge and everyday ni-Vanuatu knowledge. The author is interested in understanding the downplaying but primarily the amplification of difference with respect to place, generation and gender identities. The relationship between reproduction, social reproduction and the multiple meanings of modernity is at issue. In the expert knowledge of demography that proffers advice for the ni-Vanuatu state, it is the lack of modern development - in the form of adequate biomedical birth control, western education, and the equality of women - that is the implicit cause of population growth. Yet, many ni-Vanuatu see population growth as tied to the troubles that arise from the dilution of traditional social forms: there is too much modernity. In both demographic and ni-Vanuatu everyday narrations of the potential population crisis, diversification and mainstreaming take place and vulnerabilities are produced.

  3. Crystal phase-based epitaxial growth of hybrid noble metal nanostructures on 4H/fcc Au nanowires

    Science.gov (United States)

    Lu, Qipeng; Wang, An-Liang; Gong, Yue; Hao, Wei; Cheng, Hongfei; Chen, Junze; Li, Bing; Yang, Nailiang; Niu, Wenxin; Wang, Jie; Yu, Yifu; Zhang, Xiao; Chen, Ye; Fan, Zhanxi; Wu, Xue-Jun; Chen, Jinping; Luo, Jun; Li, Shuzhou; Gu, Lin; Zhang, Hua

    2018-03-01

    Crystal-phase engineering offers opportunities for the rational design and synthesis of noble metal nanomaterials with unusual crystal phases that normally do not exist in bulk materials. However, it remains a challenge to use these materials as seeds to construct heterometallic nanostructures with desired crystal phases and morphologies for promising applications such as catalysis. Here, we report a strategy for the synthesis of binary and ternary hybrid noble metal nanostructures. Our synthesized crystal-phase heterostructured 4H/fcc Au nanowires enable the epitaxial growth of Ru nanorods on the 4H phase and fcc-twin boundary in Au nanowires, resulting in hybrid Au-Ru nanowires. Moreover, the method can be extended to the epitaxial growth of Rh, Ru-Rh and Ru-Pt nanorods on the 4H/fcc Au nanowires to form unique hybrid nanowires. Importantly, the Au-Ru hybrid nanowires with tunable compositions exhibit excellent electrocatalytic performance towards the hydrogen evolution reaction in alkaline media.

  4. Effect of Time-Dependent Pinning Pressure on Abnormal Grain Growth: Phase Field Simulation

    Science.gov (United States)

    Kim, Jeong Min; Min, Guensik; Shim, Jae-Hyeok; Lee, Kyung Jong

    2018-05-01

    The effect of the time-dependent pinning pressure of precipitates on abnormal grain growth has been investigated by multiphase field simulation with a simple precipitation model. The application of constant pinning pressure is problematic because it always induces abnormal grain growth or no grain growth, which is not reasonable considering the real situation. To produce time-dependent pinning pressure, both precipitation kinetics and precipitate coarsening kinetics have been considered with two rates: slow and fast. The results show that abnormal grain growth is suppressed at the slow precipitation rate. At the slow precipitation rate, the overall grain growth caused by the low pinning pressure in the early stage indeed plays a role in preventing abnormal grain growth by reducing the mobility advantage of abnormal grains. In addition, the fast precipitate coarsening rate tends to more quickly transform abnormal grain growth into normal grain growth by inducing the active growth of grains adjacent to the abnormal grains in the early stage. Therefore, the present study demonstrates that the time dependence of the pinning pressure of precipitates is a critical factor that determines the grain growth mode.

  5. A 4-D dataset for validation of crystal growth in a complex three-phase material, ice cream

    Science.gov (United States)

    Rockett, P.; Karagadde, S.; Guo, E.; Bent, J.; Hazekamp, J.; Kingsley, M.; Vila-Comamala, J.; Lee, P. D.

    2015-06-01

    Four dimensional (4D, or 3D plus time) X-ray tomographic imaging of phase changes in materials is quickly becoming an accepted tool for quantifying the development of microstructures to both inform and validate models. However, most of the systems studied have been relatively simple binary compositions with only two phases. In this study we present a quantitative dataset of the phase evolution in a complex three-phase material, ice cream. The microstructure of ice cream is an important parameter in terms of sensorial perception, and therefore quantification and modelling of the evolution of the microstructure with time and temperature is key to understanding its fabrication and storage. The microstructure consists of three phases, air cells, ice crystals, and unfrozen matrix. We perform in situ synchrotron X-ray imaging of ice cream samples using in-line phase contrast tomography, housed within a purpose built cold-stage (-40 to +20oC) with finely controlled variation in specimen temperature. The size and distribution of ice crystals and air cells during programmed temperature cycling are determined using 3D quantification. The microstructural evolution of three-phase materials has many other important applications ranging from biological to structural and functional material, hence this dataset can act as a validation case for numerical investigations on faceted and non-faceted crystal growth in a range of materials.

  6. A 4-D dataset for validation of crystal growth in a complex three-phase material, ice cream

    International Nuclear Information System (INIS)

    Rockett, P; Karagadde, S; Guo, E; Kingsley, M; Lee, P D; Bent, J; Hazekamp, J; Vila-Comamala, J

    2015-01-01

    Four dimensional (4D, or 3D plus time) X-ray tomographic imaging of phase changes in materials is quickly becoming an accepted tool for quantifying the development of microstructures to both inform and validate models. However, most of the systems studied have been relatively simple binary compositions with only two phases. In this study we present a quantitative dataset of the phase evolution in a complex three-phase material, ice cream. The microstructure of ice cream is an important parameter in terms of sensorial perception, and therefore quantification and modelling of the evolution of the microstructure with time and temperature is key to understanding its fabrication and storage. The microstructure consists of three phases, air cells, ice crystals, and unfrozen matrix. We perform in situ synchrotron X-ray imaging of ice cream samples using in-line phase contrast tomography, housed within a purpose built cold-stage (-40 to +20 o C) with finely controlled variation in specimen temperature. The size and distribution of ice crystals and air cells during programmed temperature cycling are determined using 3D quantification. The microstructural evolution of three-phase materials has many other important applications ranging from biological to structural and functional material, hence this dataset can act as a validation case for numerical investigations on faceted and non-faceted crystal growth in a range of materials. (paper)

  7. Rapid evaporative ionisation mass spectrometry and chemometrics for high-throughput screening of growth promoters in meat producing animals.

    Science.gov (United States)

    Guitton, Yann; Dervilly-Pinel, Gaud; Jandova, Renata; Stead, Sara; Takats, Zoltan; Le Bizec, Bruno

    2018-01-17

    In a proof of concept perspective, Rapid Evaporative Ionisation Mass Spectrometry (REIMS) was explored for the direct analysis of meat samples from β-agonist treated livestock. In this context, the combination of REIMS with untargeted metabolomics was investigated to identify carcasses from treated animals on the basis of a modification of indirect metabolites profile. The REIMS analysis generated specific lipid profiles which enabled the differentiation of meat samples collected from pigs treated with ractopamine via their feeding regime. Furthermore, the strategy was found successful when tested on different muscle types (loin, shoulder and thigh), which further expands its applicability. Classification performances were greater than 95% accurate which fully answers requirements of a screening strategy. This research indicates that REIMS implemented in an untargeted-metabolomics workflow can be considered as a high-throughput and accurate strategy for real-time meat classification in relation to ractopamine (and wider β-agonists) treatment in pig production. This approach may subsequently be implemented as a rapid screening test, at the slaughterhouse or at border inspection points, to detect such practice.

  8. Rapid formation of phase-clean 110 K (Bi-2223) powders derived via freeze-drying process

    Science.gov (United States)

    Balachandran, U.

    1996-06-04

    A process for the preparation of amorphous precursor powders for Pb-doped Bi{sub 2}Sr{sub 2} Ca{sub 2}Cu{sub 3}O{sub x} (2223) includes a freeze-drying process incorporating a splat-freezing step. The process generally includes splat freezing a nitrate solution of Bi, Pb, Sr, Ca, and Cu to form flakes of the solution without any phase separation; grinding the frozen flakes to form a powder; freeze-drying the frozen powder; heating the dried powder to form a dry green precursor powders; denitrating the green-powders; heating the denitrated powders to form phase-clean Bi-2223 powders. The grain boundaries of the 2223 grains appear to be clean, leading to good intergrain contact between 2223 grains. 11 figs.

  9. Polypyrrole solid phase microextraction: A new approach to rapid sample preparation for the monitoring of antibiotic drugs

    International Nuclear Information System (INIS)

    Szultka, Malgorzata; Kegler, Ricarda; Fuchs, Patricia; Olszowy, Pawel; Miekisch, Wolfram; Schubert, Jochen K.; Buszewski, Boguslaw; Mundkowski, Ralf G.

    2010-01-01

    Simple or even rapid bioanalytical methods are rare, since they generally involve complicated, time-consuming sample preparation from the biological matrices like LLE or SPE. SPME provides a promising approach to overcome these limitations. The full potential of this innovative technique for medical diagnostics, pharmacotherapy or biochemistry has not been tapped yet. In-house manufactured SPME probes with polypyrrole (PPy) coating were evaluated using three antibiotics of high clinical relevance - linezolid, daptomycin, and moxifloxacin - from PBS, plasma, and whole blood. The PPy coating was characterised by scanning electron microscopy. Influences of pH, inorganic salt, and blood anticoagulants were studied for optimum performance. Extraction yields were determined from stagnant media as well as re-circulating human blood using the heart-and-lung machine model system. The PPy-SPME fibres showed high extraction yields, particularly regarding linezolid. The reproducibility of the method was optimised to achieve RSDs of 9% or 17% and 7% for SPME from stagnant or re-circulating blood using fresh and re-used fibres, respectively. The PPy-SPME approach was demonstrated to meet the requirements of therapeutic monitoring of the drugs tested, even from re-circulating blood at physiological flow rates. SPME represents a rapid and simple dual-step procedure with potency to significantly reduce the effort and expenditure of complicated sample preparations in biomedical analysis.

  10. Polypyrrole solid phase microextraction: A new approach to rapid sample preparation for the monitoring of antibiotic drugs

    Energy Technology Data Exchange (ETDEWEB)

    Szultka, Malgorzata [Department of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Nicolaus, Copernicus University, Gagarin 7, 87-100 Torun (Poland); Kegler, Ricarda [Institute of Clinical Pharmacology, University of Rostock, Schillingallee 70, D-18057 Rostock (Germany); Fuchs, Patricia [Department of Anaesthesia and Intensive Care, University of Rostock, Schillingallee 35, D-18057 Rostock (Germany); Olszowy, Pawel [Department of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Nicolaus, Copernicus University, Gagarin 7, 87-100 Torun (Poland); Miekisch, Wolfram; Schubert, Jochen K. [Department of Anaesthesia and Intensive Care, University of Rostock, Schillingallee 35, D-18057 Rostock (Germany); Buszewski, Boguslaw [Department of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Nicolaus, Copernicus University, Gagarin 7, 87-100 Torun (Poland); Mundkowski, Ralf G., E-mail: ralf.mundkowski@med.uni-rostock.de [Institute of Clinical Pharmacology, University of Rostock, Schillingallee 70, D-18057 Rostock (Germany)

    2010-05-14

    Simple or even rapid bioanalytical methods are rare, since they generally involve complicated, time-consuming sample preparation from the biological matrices like LLE or SPE. SPME provides a promising approach to overcome these limitations. The full potential of this innovative technique for medical diagnostics, pharmacotherapy or biochemistry has not been tapped yet. In-house manufactured SPME probes with polypyrrole (PPy) coating were evaluated using three antibiotics of high clinical relevance - linezolid, daptomycin, and moxifloxacin - from PBS, plasma, and whole blood. The PPy coating was characterised by scanning electron microscopy. Influences of pH, inorganic salt, and blood anticoagulants were studied for optimum performance. Extraction yields were determined from stagnant media as well as re-circulating human blood using the heart-and-lung machine model system. The PPy-SPME fibres showed high extraction yields, particularly regarding linezolid. The reproducibility of the method was optimised to achieve RSDs of 9% or 17% and 7% for SPME from stagnant or re-circulating blood using fresh and re-used fibres, respectively. The PPy-SPME approach was demonstrated to meet the requirements of therapeutic monitoring of the drugs tested, even from re-circulating blood at physiological flow rates. SPME represents a rapid and simple dual-step procedure with potency to significantly reduce the effort and expenditure of complicated sample preparations in biomedical analysis.

  11. Chronic Subdural Hematoma development in Accelerated phase of Chronic Myeloid Leukaemia presenting with seizure and rapid progression course with fatal outcome

    Directory of Open Access Journals (Sweden)

    Raheja Amol

    2015-06-01

    Full Text Available Occurrence of chronic subdural hematoma (CSDH in leukemia is rare, and most reported cases occurred in relation with acute myeloid leukaemia; however, occurrence is extremely rare in accelerated phase of chronic myelogenous leukaemia (CML. Seizure as presentation of SDH development in CML cases is not reported in literature. Authors report an elderly male, who was diagnosed as CML, accelerated phase of developing SDH. Initially presented to local physician with seizure; urgent CT scan head was advised, but ignored and sensorium rapidly worsened over next day and reported to our emergency department in deeply comatose state, where imaging revealed chronic subdural hematoma with hypoxic brain injury with fatal outcome. Seizure, progressive worsening of headache, vomiting and papilloedema are harbinger of intracranial space occupying lesion and requires CT head in emergency medical department for exclusion, who are receiving treatment of haematological malignancy

  12. Two-phase mixture level swell and liquid entrainment/off-take in a vessel during rapid depressurization

    International Nuclear Information System (INIS)

    Kim, Chang Hyun

    2004-02-01

    An experimental study has been performed to analyze the two-phase mixture level swell and the liquid entrainment/off-take through the break in a vessel, which are important phenomena to determine the bleed capacity of the Safety Depressurization System (SDS) of Korea Advanced Power Reactor 1400 (APR1400). Three separate experiments are performed in this study: (a) the depressurization and two-phase mixture level swell experiment: (b) the two-phase mixture level measurement experiment: (c) the liquid entrainment and off-take experiment. A series of experiments has been performed using a scaled pressurized vessel in various depressurization conditions to analyze the two-phase mixture level swell and the liquid entrainment/off-take phenomena from the two-phase mixture surface in the first experiment. The test parameters are the initial pressure (10 - 38.75bars), the initial water level (43.7% - 80.0% of full height), the orifice inner diameter (10mm, 17.5mm, and 20mm). The liquid off-take takes place in certain experimental conditions. The measured parameters in the present experiments are axial void fraction distributions, pressures, temperatures in the test vessel, and the mixture density and mass flowrate through the discharge pipe. An assessment of RELAP5/MOD3 code with the present experimental data has been performed. With appropriate nodalization and time step, RELAP5/MOD3 showed reasonable agreement with the present experimental data for the gradual depressurization without liquid off-take. In the case that the off-take takes place, however, RELAP5/MOD3 under-predicts the amount of liquid entrainment/off-take during depressurization. In the second experiment, an assessment of an ultrasonic sensor and a two-wire type capacitance probe for the two-phase mixture level measurement has been performed under the same experimental conditions to adopt an appropriate measurement method for the two-phase mixture level swell and to investigate pool void fraction by the

  13. A generalized-growth model to characterize the early ascending phase of infectious disease outbreaks

    Directory of Open Access Journals (Sweden)

    Cécile Viboud

    2016-06-01

    Conclusions: Our findings reveal significant variation in epidemic growth patterns across different infectious disease outbreaks and highlights that sub-exponential growth is a common phenomenon, especially for pathogens that are not airborne. Sub-exponential growth profiles may result from heterogeneity in contact structures or risk groups, reactive behavior changes, or the early onset of interventions strategies, and consideration of “deceleration parameters” may be useful to refine existing mathematical transmission models and improve disease forecasts.

  14. Growth of single - crystals of Pb1-x Snx Te by vapor phase transport with the formation of a liquid/solid growth interface

    International Nuclear Information System (INIS)

    An, C.Y.; Bandeira, I.N.

    1985-01-01

    Due to segregation effects single-crystals of Pb 1-x Sn x Te growth by Bridgman techniques have an inhomogeneous composition profile. A vapor phase transport growth process has been developed in order to reduce convective flows. This is due to the very thin melt layer in front of the crystal, that makes convective flows small and solute mixing in the melt very low. By this process single-crystals with 60mm length by 15 mm diameter and a high degree of homogeneity have been grown. A process for determination of the exact composition profile by measurements of the crystal density, for isomorphous alloys of the type A 1-x B x , is also shown. (Author) [pt

  15. Chirality-Controlled Growth of Single-Wall Carbon Nanotubes Using Vapor Phase Epitaxy: Mechanistic Understanding and Scalable Production

    Science.gov (United States)

    2016-09-15

    AFRL-AFOSR-VA-TR-2016-0319 Chirality -Controlled Growth of Single-Wall Carbon Nanotubes Using Vapor Phase Epitaxy: Mechanistic Understanding and...TELEPHONE NUMBER (Include area code) DISTRIBUTION A: Distribution approved for public release. 15-06-2016 final Jun 2014 - Jun 2016 Chirality ...for Public Release; Distribution is Unlimited. In this report, we present our efforts in establishing a novel and effective approach for chirality

  16. Effect of gas flow on the selective area growth of gallium nitride via metal organic vapor phase epitaxy

    Science.gov (United States)

    Rodak, L. E.; Kasarla, K. R.; Korakakis, D.

    2007-08-01

    The effect of gas flow on the selective area growth (SAG) of gallium nitride (GaN) grown via metal organic vapor phase epitaxy (MOVPE) has been investigated. In this study, the SAG of GaN was carried out on a silicon dioxide striped pattern along the GaN direction. SAG was initiated with the striped pattern oriented parallel and normal to the incoming gas flow in a horizontal reactor. The orientation of the pattern did not impact cross section of the structure after re-growth as both orientations resulted in similar trapezoidal structures bounded by the (0 0 0 1) and {1 1 2¯ n} facets ( n≈1.7-2.2). However, the growth rates were shown to depend on the orientation of the pattern as the normally oriented samples exhibited enhanced vertical and cross-sectional growth rates compared to the parallel oriented samples. All growths occurred under identical conditions and therefore the difference in growth rates must be attributed to a difference in mass transport of species.

  17. Low-Temperature Rapid Fabrication of ZnO Nanowire UV Sensor Array by Laser-Induced Local Hydrothermal Growth

    Directory of Open Access Journals (Sweden)

    Sukjoon Hong

    2013-01-01

    Full Text Available We demonstrate ZnO nanowire based UV sensor by laser-induced hydrothermal growth of ZnO nanowire. By inducing a localized temperature rise using focused laser, ZnO nanowire array at ~15 μm size consists of individual nanowires with ~8 μm length and 200~400 nm diameter is readily synthesized on gold electrode within 30 min at the desired position. The laser-induced growth process is consecutively applied on two different points to bridge the micron gap between the electrodes. The resultant photoconductive ZnO NW interconnections display 2~3 orders increase in the current upon the UV exposure at a fixed voltage bias. It is also confirmed that the amount of photocurrent can be easily adjusted by changing the number of ZnO NW array junctions. The device exhibits clear response to the repeated UV illumination, suggesting that this process can be usefully applied for the facile fabrication of low-cost UV sensor array.

  18. A Phase II Trial of Docetaxel with Rapid Androgen Cycling as a Treatment for Patients with Prostate Cancer

    Science.gov (United States)

    Rathkopf, Dana; Carducci, Michael A.; Morris, Michael J.; Slovin, Susan F.; Eisenberger, Mario A.; Pili, Roberto; Denmeade, Samuel R.; Kelsen, Moshe; Curley, Tracy; Priet, Regina; Collins, Connie; Fleisher, Martin; Heller, Glenn; Baker, Sharyn D.; Scher, Howard I.

    2011-01-01

    Purpose We evaluated rapid androgen cycling in combination with docetaxel for men with progressive non-castrate prostate cancers. Methods Non-castrate patients with ≤ 6 months of hormones were eligible. Cohort 1 (63 patients ) received 6 28-day cycles of docetaxel (75 mg/m2), leuprolide and 7 days of topical testosterone. Cohort 2 (39 patients) received 9 21-day cycles of docetaxel (70 mg/m2), leuprolide and 3 days of testosterone. The primary endpoint was the proportion of patients at 18 months who achieved non -castrate testosterone levels (>150 ng/dl) and an undetectable PSA (≤ 0.05, ≤0.5, or ≤2.0 ng/ml with prior prostatectomy, radiotherapy, or no definitive therapy, respectively). Cytochrome P450 3A4 (CYP3A4) activity and docetaxel pharmacokinetics were evaluated. Results A higher proportion of patients achieved the undetectable PSA outcome at 18 months in cohort 2 relative to cohort 1 (13% vs. 0%). The 16% incidence of febrile neutropenia was higher than observed in patients was castration-resistant disease, which may have been related to a 50% reduction in overall docetaxel clearance in the non-castrate group. There was no alteration in CYP3A4 activity (P=0.87) or docetaxel clearance (P=0.88) between cycles. Conclusions The undetectable PSA endpoint allows for a rapid screening of interventions for further study. Increasing the number of docetaxel cycles following a shorter period of testosterone repletion, and a longer duration of testosterone depletion, increased the proportion of men who achieved an undetectable PSA. The higher-than-expected incidence of febrile neutropenia may have been related to the reduced overall docetaxel clearance in patients with non-castrate vs castrate testosterone levels. PMID:18565882

  19. Preparation of {sup 183,184}Re samples for modelling a rapid gas phase chemistry of Nielsbohrium (Ns), element 107

    Energy Technology Data Exchange (ETDEWEB)

    Eichler, R.; Gaeggeler, H.W.; Eichler, B.; Tuerler, A. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-09-01

    Chemical gas phase reactions of the heavier group 7 elements in the system O{sub 2}/H{sub 2}O are presumably best suited for a separation of Nielsbohrium from the lighter transactinides. We expect a higher reaction velocity using the more reactive gas system O{sub 3}/H{sub 2}O{sub 2}. For the experimental verification of this idea we prepared {sup 183}Re/{sup 184}Re samples for thermochromatography experiments with both gas systems. (author) 8 refs.

  20. Trade-offs between microbial growth phases lead to frequency-dependent and non-transitive selection.

    Science.gov (United States)

    Manhart, Michael; Adkar, Bharat V; Shakhnovich, Eugene I

    2018-02-14

    Mutations in a microbial population can increase the frequency of a genotype not only by increasing its exponential growth rate, but also by decreasing its lag time or adjusting the yield (resource efficiency). The contribution of multiple life-history traits to selection is a critical question for evolutionary biology as we seek to predict the evolutionary fates of mutations. Here we use a model of microbial growth to show that there are two distinct components of selection corresponding to the growth and lag phases, while the yield modulates their relative importance. The model predicts rich population dynamics when there are trade-offs between phases: multiple strains can coexist or exhibit bistability due to frequency-dependent selection, and strains can engage in rock-paper-scissors interactions due to non-transitive selection. We characterize the environmental conditions and patterns of traits necessary to realize these phenomena, which we show to be readily accessible to experiments. Our results provide a theoretical framework for analysing high-throughput measurements of microbial growth traits, especially interpreting the pleiotropy and correlations between traits across mutants. This work also highlights the need for more comprehensive measurements of selection in simple microbial systems, where the concept of an ordinary fitness landscape breaks down. © 2018 The Author(s).

  1. Experimental evidence for several spheroid growth mechanisms in the liquid-phase sintered tungsten-base composites

    International Nuclear Information System (INIS)

    Zukas, E.G.; Rogers, P.S.Z.; Rogers, R.S.

    1976-01-01

    The generally accepted mechanism for spheroid growth during sintering of tungsten-base composites in the presence of a liquid phase is the dissolution of the small spheroids with simultaneous precipitation of tungsten from the molten matrix onto the larger spheroids, the process being driven by the difference in surface energy between the larger and smaller spheroids. From theoretical considerations, the slope of the straight line of log diameter versus log time should be 1 / 3 for this process. The experimental evidence for the dissolution and reprecipitation mechanism is meager, being based primarily on the spheroid growth rate during the latter stages of liquid-phase sintering. Experimental evidence is presented that shows spheroid growth taking place in systems where the tungsten and the matrix are mutually insoluble thereby making dissolution and reprecipitation impossible. Furthermore, the results from these studies and others using the usual matrix compositions indicate that spheroid growth takes place predominantly by the combination or coalescence of two or more spheroids. Deposition of tungsten from the molten matrix also occurs, although not necessarily on spheroid surfaces which have the lowest surface energy. Thus, many mechanisms, each depending on temperature and other variables, operate simultaneously. A satisfactory theoretical treatment must include them all

  2. Effect of benzalkonium chloride on viability and energy metabolism in exponential- and stationary-growth-phase cells of Listeria monocytogenes.

    Science.gov (United States)

    Luppens, S B; Abee, T; Oosterom, J

    2001-04-01

    The difference in killing exponential- and stationary-phase cells of Listeria monocytogenes by benzalkonium chloride (BAC) was investigated by plate counting and linked to relevant bioenergetic parameters. At a low concentration of BAC (8 mg liter(-1)), a similar reduction in viable cell numbers was observed for stationary-phase cells and exponential-phase cells (an approximately 0.22-log unit reduction), although their membrane potential and pH gradient were dissipated. However, at higher concentrations of BAC, exponential-phase cells were more susceptible than stationary-phase cells. At 25 mg liter(-1), the difference in survival on plates was more than 3 log units. For both types of cells, killing, i.e., more than 1-log unit reduction in survival on plates, coincided with complete inhibition of acidification and respiration and total depletion of ATP pools. Killing efficiency was not influenced by the presence of glucose, brain heart infusion medium, or oxygen. Our results suggest that growth phase is one of the major factors that determine the susceptibility of L. monocytogenes to BAC.

  3. Growth of β-FeSi2 layers on Si (111) by solid phase and reactive deposition epitaxies

    International Nuclear Information System (INIS)

    Miquita, D.R.; Paniago, R.; Rodrigues, W.N.; Moreira, M.V.B.; Pfannes, H.-D.; Oliveira, A.G. de

    2005-01-01

    Iron silicides were grown on Si (111) substrates by Solid Phase Epitaxy (SPE) and Reactive Deposition Epitaxy (RDE) to identify the optimum conditions to obtain the semiconducting β-FeSi 2 phase. The films were produced under different growth and annealing conditions and analyzed in situ and ex situ by X-ray Photoelectron Spectroscopy, and ex situ by Conversion Electron Moessbauer Spectroscopy. The use of these techniques allowed the investigation of different depth regions of the grown layer. Films of the ε-FeSi and β-FeSi 2 phases were obtained as well as the mixtures Fe 3 Si + ε-FeSi and ε-FeSi + β-FeSi 2 . The sequence Fe 3 Si→ε-FeSi→β-FeSi 2 was found upon annealing, where the phase transformation occurred due to the migration of silicon atoms from the substrate to the surface region of the grown layer. The best conditions for the phase transformation in SPE samples were met after annealing in the range 700 - 800 deg. C. For the RDE samples, the transition to the beta phase occurred between 600 and 700 deg. C, but pure β-FeSi 2 was obtained only after two hours of annealing at 700 deg. C

  4. Application of analytical capability to predict rapid cladding cooling and quench during the blowdown phase of a large break loss-of-coolant accident

    International Nuclear Information System (INIS)

    Aksan, S.N.; Tolman, E.L.; Nelson, R.A.

    1983-01-01

    Large-break Experiments L2-2 and L2-3 conducted in the Loss-of-Fluid Test (LOFT) facility experienced core-wide rapid quenches early in the blowdown transients. To further investigate rapid cladding quenches, separate effects experiments using Semiscale solid-type electric heater rods were conducted in the LOFT Test Support Facility (LTSF) over a wide range of inlet coolant conditions. The analytical capability to predict the cladding temperature response from selected LTSF experiments estimated to bound the hydraulic conditions causing the LOFT early blowdown quenches was investigated using the RELAP4 computer code and was shown to be acceptable over the film boiling cooldown phase. This analytical capability was then used to investigate the behavior of nuclear fuel rods under the same hydraulic conditions. The calculations show that, under rapid cooling conditions, the behaviors of nuclear and electrical heater rods are significantly different because the nuclear rods are conduction limited, while the electrical rods are convection limited

  5. Phase- and shape-controlled hydrothermal synthesis of CdS nanoparticles, and oriented attachment growth of its hierarchical architectures

    Science.gov (United States)

    Cao, Yali; Hu, Pengfei; Jia, Dianzeng

    2013-01-01

    Hydrothermal strategies were successfully used to control the phases and morphologies of CdS nanocrystals. In the absence of an external direction-controlling process, the hexagonal and cubic phase well-defined leaf- and flower-like CdS nanocrystals were controlled obtained via adjusting the reaction duration or the concentration of surfactant. Oriented attachment growth modes were suggested for the formation of CdS superstructures, which was clarified through the tracing of temporal evolution of CdS nanoparticles. The CdS superstructures were structured by primary building nanoparticles, and held excellent visible emission with a peak in the green regions. This strategy is very helpful for studying the phase and morphology controlled fabrication of sulfides nanocrystals.

  6. In situ electron beam irradiated rapid growth of bismuth nanoparticles in bismuth-based glass dielectrics at room temperature

    International Nuclear Information System (INIS)

    Singh, Shiv Prakash; Karmakar, Basudeb

    2011-01-01

    In this study, in situ control growth of bismuth nanoparticles (Bi 0 NPs) was demonstrated in bismuth-based glass dielectrics under an electron beam (EB) irradiation at room temperature. The effects of EB irradiation were investigated in situ using transmission electron microscopy (TEM), selected-area electron diffraction and high-resolution transmission electron microscopy. The EB irradiation for 2–8 min enhanced the construction of bismuth nanoparticles with a rhombohedral structure and diameter of 4–9 nm. The average particle size was found to increase with the irradiation time. Bismuth metal has a melting point of 271 °C and this low melting temperature makes easy the progress of energy induced structural changes during in situ TEM observations. This is a very useful technique in nano-patterning for integrated optics and other applications.

  7. A rapid [3H]glucose incorporation assay for determination of lymphoid cell-mediated inhibition of Candida albicans growth

    International Nuclear Information System (INIS)

    Djeu, J.Y.; Parapanissios, A.; Halkias, D.; Friedman, H.

    1986-01-01

    [ 3 H]glucose uptake by Candida albicans after interaction with lymphoid effector cells was used to provide a quick, accurate and objective assessment of the growth inhibitory potential of lymphoid cells on candida. After 18 h coincubation of effector cells with candida, [ 3 H]glucose was added for 3 h and the amount of radiolabel incorporated into residual candida was measured. The results showed that [ 3 H]glucose uptake was proportional to the number of candida organisms left in the microwell and is dose dependent on the effector/target (E/T) ratio. At an E/T ratio of 300/1, complete inhibition of candida was seen, with significant inhibition still present at 30/1. In addition, monocytes and polymorphonuclear cells were found to be the primary cells responsible for eliminating candida. (Auth.)

  8. The nutrition transition in amazonia: rapid economic change and its impact on growth and development in Ribeirinhos.

    Science.gov (United States)

    Piperata, Barbara A; Spence, Jennifer E; Da-Gloria, Pedro; Hubbe, Mark

    2011-09-01

    The goal of this longitudinal study was to assess the impact of economic change and increased market integration on subsistence strategies, living conditions, growth, and nutritional status of Ribeirinhos living in the rural Amazon, Brazil. Data on weight, height, skinfolds, and circumferences, as well as data on economic strategies and living conditions were collected from 469 individuals in 2002 and 429 in 2009. Of these, 204 individuals were measured on both occasions. Independent and paired t-tests were used to identify changes in nutritional status over time in the larger sample and smaller, longitudinal subsample, respectively. Multiple linear regressions were used to examine the relationship between changes in economic/living conditions and nutritional status in the longitudinal subsample. Results indicate modest improvements in linear growth (HAZ) and among male children the observed increase was related to enrollment in the Brazilian conditional cash transfer program, Bolsa Família (P = 0.03). In terms of short-term measures of nutritional status, we found a significant increase in ZTSF and a reduction in ZUMA in most age/sex groups. Among subadults, there was a negative relationship between ZUMA and access to electricity (P = 0.01) and positive relationship between ZUMA and the sale of the açaí fruit (P = 0.04). Significant changes in weight and BMI (P economic strategies and lifestyle, changes in nutritional status were modest which may be explained by increased food insecurity documented during this early stage of transition. 2010 Wiley-Liss, Inc.

  9. Rapid Turnover and Minimal Accretion of Mineral Soil Carbon During 60-Years of Pine Forest Growth on Previously Cultivated Land

    Science.gov (United States)

    Richter, D., Jr.; Mobley, M. L.; Billings, S. A.; Markewitz, D.

    2016-12-01

    At the Calhoun Long-Term Soil-Ecosystem field experiment (1957-present), reforestation of previously cultivated land over fifty years nearly doubled soil organic carbon (SOC) in surface soils (0 to 7.5-cm) but these gains were offset by significant SOC losses in subsoils (35 to 60-cm). Nearly all of the accretions in surface soils amounted to gains in light fraction SOC, whereas losses at depth were associated with silt and clay-sized particles. These changes are documented in the Calhoun Long-Term Soil-Ecosystem (LTSE) study that resampled soil from 16 plots about every five years and archived all soil samples from four soil layers within the upper 60-cm of mineral soil. We combined soil bulk density, density fractionation, stable isotopes, and radioisotopes to explore changes in SOC and soil organic nitrogen (SON) associated with five decades of the growth of a loblolly pine secondary forest. Isotopic signatures showed relatively large accumulations of contemporary forest-derived carbon in surface soils, and no accumulation of forest-derived carbon in subsoils. We interpret results to indicate that land-use change from cotton fields to secondary pine forests drove soil biogeochemical and hydrological changes that enhanced root and microbial activity and SOM decomposition in subsoils. As pine stands matured and are now transitioning to mixed pines and hardwoods, demands on soil organic matter for nutrients to support aboveground growth has eased due to pine mortality, and bulk SOM and SON and their isotopes in subsoils have stabilized. We anticipate major changes in the next fifty years as 1957 pine trees transition to hardwoods. This study emphasizes the importance of long-term experiments and deep soil measurements when characterizing SOC and SON responses to land use change. There is a remarkable paucity of E long-term soil data deeper than 30 cm.

  10. Molecular beam epitaxy growth of In0.52Al0.48As/In0.53Ga0.47As metamorphic high electron mobility transistor employing growth interruption and in situ rapid thermal annealing

    International Nuclear Information System (INIS)

    Ihn, Soo-Ghang; Jo, Seong June; Song, Jong-In

    2006-01-01

    We investigated the effects of high temperature (∼700 deg. C) in situ rapid thermal annealing (RTA) carried out during growth interruption between spacer and δ-doping layers of an In 0.52 Al 0.48 As/In 0.53 Ga 0.47 As metamorphic high electron mobility transistor (MHEMT) grown on a compositionally graded InGaAlAs buffer layer. The in situ RTA improved optical and structural properties of the MHEMT without degradation of transport property, while postgrowth RTA improved the structural property of the MHEMT but significantly degraded mobility due to the defect-assisted Si diffusion. The results indicate the potential of the in situ RTA for use in the growth of high-quality metamorphic epitaxial layers for optoelectronic applications requiring improved optical and electrical properties

  11. Na-Si binary phase diagram and solution growth of silicon crystals

    International Nuclear Information System (INIS)

    Morito, H.; Yamada, T.; Ikeda, T.; Yamane, H.

    2009-01-01

    In the present study, a Na-Si binary phase diagram was first presented from the results of differential thermal analysis and X-ray diffraction. Based on the phase diagram, we performed low-temperature formation of single crystals, film and porous bulk of Si by vaporizing Na from a Na-Si melt at 800 or 900 deg. C.

  12. Orthopedic treatment of Class III malocclusion with rapid maxillary expansion combined with a face mask: a cephalometric assessment of craniofacial growth patterns

    Directory of Open Access Journals (Sweden)

    Daniella Torres Tagawa

    2012-06-01

    Full Text Available OBJECTIVE: The aim of this prospective study was to assess potential changes in the cephalometric craniofacial growth pattern of 17 children presenting Angle Class III malocclusion treated with a Haas-type expander combined with a face mask. METHODS: Lateral cephalometric radiographs were taken at beginning (T1 and immediately after removal of the appliances (T2, average of 11 months of treatment. Linear and angular measurements were used to evaluate the cranial base, dentoskeletal changes and facial growth pattern. RESULTS: The length of the anterior cranial base experienced a reduction while the posterior cranial base assumed a more vertical position at T1. Some maxillary movement occurred, there was no rotation of the palatal plane, there was a slight clockwise rotation of the mandible, although not significant. The ANB angle increased, thereby improving the relationship between the jaws; dentoalveolar compensation was more evident in the lower incisors. Five out of 12 cases (29.41% showed the following changes: In one case the pattern became more horizontal and in four cases more vertical. CONCLUSIONS: It was concluded after a short-term assessment that treatment with rapid maxillary expansion (RME associated with a face mask was effective in the correction of Class III malocclusion despite the changes in facial growth pattern observed in a few cases.

  13. Plasma leptin and growth hormone levels in the fine flounder (Paralichthys adspersus) increase gradually during fasting and decline rapidly after refeeding.

    Science.gov (United States)

    Fuentes, Eduardo N; Kling, Peter; Einarsdottir, Ingibjörg Eir; Alvarez, Marco; Valdés, Juan Antonio; Molina, Alfredo; Björnsson, Björn Thrandur

    2012-05-15

    In fish, recent studies have indicated an anorexigenic role of leptin and thus its possible involvement in regulation of energy balance and growth. In the present study, the effects of fasting and refeeding periods on plasma leptin levels were studied in the fine flounder, a flatfish with remarkably slow growth. To further assess the endocrine status of the fish during periods of catabolism and anabolism, plasma growth hormone (GH) levels were also analyzed. Under normal feeding condition, plasma leptin and GH levels remained stable and relatively high in comparison with other teleost species. For the three separate groups of fish, fasted for 2, 3, and 4 weeks, respectively, plasma leptin levels increase gradually, becoming significantly elevated after 3 weeks, and reaching highest levels after 4-week fasting. Plasma GH levels were significantly elevated after 2-week fasting. At the onset of refeeding, following a single meal, leptin levels decline rapidly to lower than initial levels within 2 h, irrespective of the length of fasting. Plasma GH also decline, the decrease being significant after 4, 24 and 2 h for the 2, 3 and 4-week fasted groups, respectively. This study shows that plasma leptin levels in the fine flounder are strongly linked to nutritional status and suggests that leptin secretion is regulated by fast-acting mechanisms. Elevated leptin levels in fasted fish may contribute to a passive survival strategy of species which experience natural food shortage periods by lowering appetite and limiting physical foraging activity. Copyright © 2012 Elsevier Inc. All rights reserved.

  14. Body Growth and Rapid Hematological Development Support Breath Hold of Baby Belugas (Delphinapterus leucas) during Subice Transit.

    Science.gov (United States)

    Noren, Shawn R; Poll, Caryn P; Edwards, Matthew S

    Body size and oxygen stores in the blood and muscle set breath-hold limits in marine mammals, yet these characteristics are understudied in immature cetaceans. We examined body mass and hematology from birth through adulthood in beluga whales (Delphinapterus leucas). At birth, body mass was 8% and 6% of the maximum mass recorded for adult females and males, respectively. Body mass then increased rapidly, approaching an asymptote around 12 yr for females and 18 yr for males. Interestingly, red blood cell counts, hemoglobin content, and hematocrit levels decreased after birth; this neonatal anemia was reversed as levels increased after 2 mo postpartum. Mature levels were obtained at approximately 8, 9, and 11 mo postpartum, respectively. Neonatal mean corpuscular hemoglobin also increased with ontogeny; mature levels were achieved by approximately 13 mo after birth. In contrast, mean corpuscular volume and mean corpuscular hemoglobin concentration demonstrated a significant but subtle increase throughout ontogeny. Our results indicate that postnatal maturation was required and that maturation occurred far earlier than the age at weaning (i.e., 2-3 yr postpartum). This is atypical of marine mammals, which generally achieve mature hemoglobin levels at weaning. Hematological maturation before maternal independence undoubtedly supports the prolonged breath holds of young belugas transiting under sea ice. This assessment enhances our knowledge of cetacean physiology and provides important inputs for determining age-specific dive capacity, yielding insights into age-specific flexibility to alter underwater behaviors, as will be required for future regime shifts and disturbances.

  15. Increase of vitamin D2 by UV-B exposure during the growth phase of white button mushroom (Agaricus bisporus

    Directory of Open Access Journals (Sweden)

    Hanne L. Kristensen

    2012-04-01

    Full Text Available Background: Mushrooms are the only non-animal food source of vitamin D. Wild mushrooms have naturally high vitamin D2 content, and cultivated mushrooms produce vitamin D2 from ergosterol when exposed to supplementary UV-B during the post-harvest phase.Objectives: This study investigated the effects of providing supplementary UV-B during the growth phase on vitamin D2 formation and the interactions with growth of mushrooms, as compared to supplementary UV-B during the post-harvest phase or exposure to sunlight for both cultivated and wild mushrooms.Methods: Experiments were carried out with exposure to supplementary UV-B just prior to harvest in the range of 0–2,400 mJ cm−2. Mushrooms grew for 2 days with or without repeated UV-B exposure each day. Vitamin D2 and growth rate were determined. In addition, some mushrooms were post-harvest treated by exposure at 200 mJ cm−2 supplementary UV-B or natural sunlight, prior to vitamin D2 determination.Results: The content of vitamin D2 was 0.2–164 µg 100 g−1 fresh weight, and there was a linear relationship between UV-dose up to 1,000 mJ cm−2 and vitamin D2 content. The fast growth rate of the mushrooms diluted the vitamin D2 from 24 to 3 µg 100 g−1 within 2 days of exposure at 200 mJ cm−2. Following repeated UV-B exposure, vitamin D2 increased to 33 µg vitamin D2 100 g−1. Growth was unaffected by UV-B. Post-harvest exposure to supplementary UV-B resulted in a higher vitamin D2 content of 32 µg 100 g−1 compared to the 24 µg 100 g−1 obtained from exposure to UV-B during the growth phase. In contrast, wild and cultivated mushrooms with and without exposure to sunlight had vitamin D2 content in the range of 0.2–1.5 µg vitamin D2 100 g−1.Conclusions: This study showed that mushrooms with a well-defined content of vitamin D2 can be obtained by exposure to supplementary UV-B just prior to harvest.

  16. Rapid Determination of Trace Palladium in Active Pharmaceutical Ingredients by Magnetic Solid-Phase Extraction and Flame Atomic Absorption Spectrometry

    Science.gov (United States)

    Yin, Q. H.; Zhu, D. M.; Yang, D. Z.; Hu, Q. F.; Yang, Y. L.

    2018-01-01

    Clutaraldehyde cross-linked magnetic chitosan nanoparticles were synthesized and used as an adsorbent for the dispersive solid-phase extraction of palladium in active pharmaceutical ingredients (APIs) prior to analysis by a flame atomic absorption spectrophotometer. FT-IR, X-ray diffraction, and TEM were used to characterize the adsorbent. Various parameters of experimental performance, such as adsorbent amount, pH, adsorption time, desorption solutions, coexisting ions, and adsorbent reusability, were investigated and optimized. Under the optimized conditions, good linearity was achieved in the 5.0-500 μg/L concentration range, with correlation coefficients of 0.9989. The limit of detection is 2.8 μg/L and the recoveries of spiked samples ranged from 91.7 to 97.6%. It was confirmed that the GMCNs nanocomposite was a promising adsorbing material for extraction and preconcentration of Pd in APIs.

  17. Rapid and Simple Determination of Sarafloxacin and Difloxacin in Beef by Capillary Electrophoresis Coupled with Solid-Phase Extraction

    Directory of Open Access Journals (Sweden)

    Qian Wang

    2018-01-01

    Full Text Available A simple and rapid capillary electrophoresis method with diode array detector was developed for determination of sarafloxacin and difloxacin in beef. In this study, the experimental parameters affecting the determination were systematically optimized, including wavelength, buffer system, pH and concentration, and separation temperature and voltage. Under the optimal conditions, sarafloxacin and difloxacin could be quantified within 4 min using H3BO3/Na2B4O7 buffer (35 mmol/L, pH 8.8 as background electrolyte, 25 kV as separation voltage, and 22°C as the column temperature. The linear range of the method was 1–20 μg/mL with LOD 0.8 μg/mL for sarafloxacin and 0.5–20 μg/mL with LOD 0.3 μg/mL for difloxacin. The RSDs for the peak area of 8 μg/mL sarafloxacin were 4.8% (intraday and 7.8% (interday, respectively. The proposed method has been applied to determine the residue of sarafloxacin and difloxacin in beef samples with the satisfactory recovery.

  18. Quantification of whey proteins by reversed phase-HPLC and effectiveness of mid-infrared spectroscopy for their rapid prediction in sweet whey.

    Science.gov (United States)

    Sturaro, Alba; De Marchi, Massimo; Masi, Antonio; Cassandro, Martino

    2016-01-01

    In the dairy industry, membrane filtration is used to reduce the amount of whey waste and, simultaneously, to recover whey proteins (WP). The composition of WP can strongly affect the filtration treatment of whey, and rapid determination of WP fractions would be of interest for dairy producers to monitor WP recovery. This study aimed to develop mid-infrared spectroscopy (MIRS) prediction models for the rapid quantification of protein in sweet whey, using a validated rapid reversed phase (RP)-HPLC as a reference method. Quantified WP included α-lactalbumin (α-LA), β-lactoglobulin (β-LG) A and B, bovine serum albumin, caseinomacropeptides, and proteose peptone. Validation of RP-HPLC was performed by calculating the relative standard deviation (RSD) in repeatability and reproducibility tests for WP retention time and peak areas. Samples of liquid whey (n=187) were analyzed by RP-HPLC and scanned through MIRS to collect spectral information (900 to 4,000 cm(-1)); statistical analysis was carried out through partial least squares regression and random cross-validation procedure. Retention times in RP-HPLC method were stable (RSD between 0.03 and 0.80%), whereas the RSD of peak area (from 0.25 to 8.48%) was affected by WP relative abundance. Higher coefficients of determination in validation for MIRS model were obtained for protein fractions present in whey in large amounts, such as β-LG (0.58), total identified WP (0.58), and α-LA (0.56). Results of this study suggest that MIRS is an easy method for rapid quantification of detail protein in sweet whey, even if better resolution was achieved with the method based on RP-HPLC. The prediction of WP in sweet whey by MIRS might be used for screening and for classifying sweet whey according to its total and individual WP contents. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  19. Modelling multi-phase liquid-sediment scour and resuspension induced by rapid flows using Smoothed Particle Hydrodynamics (SPH) accelerated with a Graphics Processing Unit (GPU)

    Science.gov (United States)

    Fourtakas, G.; Rogers, B. D.

    2016-06-01

    A two-phase numerical model using Smoothed Particle Hydrodynamics (SPH) is applied to two-phase liquid-sediments flows. The absence of a mesh in SPH is ideal for interfacial and highly non-linear flows with changing fragmentation of the interface, mixing and resuspension. The rheology of sediment induced under rapid flows undergoes several states which are only partially described by previous research in SPH. This paper attempts to bridge the gap between the geotechnics, non-Newtonian and Newtonian flows by proposing a model that combines the yielding, shear and suspension layer which are needed to predict accurately the global erosion phenomena, from a hydrodynamics prospective. The numerical SPH scheme is based on the explicit treatment of both phases using Newtonian and the non-Newtonian Bingham-type Herschel-Bulkley-Papanastasiou constitutive model. This is supplemented by the Drucker-Prager yield criterion to predict the onset of yielding of the sediment surface and a concentration suspension model. The multi-phase model has been compared with experimental and 2-D reference numerical models for scour following a dry-bed dam break yielding satisfactory results and improvements over well-known SPH multi-phase models. With 3-D simulations requiring a large number of particles, the code is accelerated with a graphics processing unit (GPU) in the open-source DualSPHysics code. The implementation and optimisation of the code achieved a speed up of x58 over an optimised single thread serial code. A 3-D dam break over a non-cohesive erodible bed simulation with over 4 million particles yields close agreement with experimental scour and water surface profiles.

  20. Solution-phase epitaxial growth of quasi-monocrystalline cuprous oxide on metal nanowires

    NARCIS (Netherlands)

    Sciacca, Beniamino; Mann, Sander A.; Tichelaar, Frans D.; Zandbergen, Henny W.; Van Huis, Marijn A.; Garnett, Erik C.

    2014-01-01

    The epitaxial growth of monocrystalline semiconductors on metal nanostructures is interesting from both fundamental and applied perspectives. The realization of nanostructures with excellent interfaces and material properties that also have controlled optical resonances can be very challenging. Here

  1. Crystal Growth of New Radiation Detector Materials in Microgravity, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — RMD proposes to conduct a series of crystal growth experiments on the International Space Station in the SUBSA furnace inside the MSG glovebox to grow crystals of...

  2. Strategy to usher in the next phase of growth in the Indian IT industry

    Directory of Open Access Journals (Sweden)

    Narendra M. Agrawal

    2012-09-01

    Full Text Available While the Indian IT/ITeS sector has registered tremendous growth over the last two decades, the viability of the growth models adopted by the IT organisations is now in question. This article, in its first part, assesses the value pyramid of the Indian IT services and in examining the avenues of growth up the value chain, suggests that the industry’s involvement in inclusive growth and holistic development of society is imperative in the journey forward. A discussion with industry practitioners in the second part of the article throws light on the strategies and initiatives being taken in the industry to meet the challenges and opportunities going forward.

  3. GaN Bulk Growth and Epitaxy from Ca-Ga-N Solutions, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The innovations proposed here are Ka-band (38 GHz) group III-nitride power FETs and the dislocation density reducing epitaxial growth methods (LPE) needed for their...

  4. Apoptosis induced by cold shock in vitro is dependent on cell growth phase.

    Science.gov (United States)

    Soloff, B L; Nagle, W A; Moss, A J; Henle, K J; Crawford, J T

    1987-06-15

    Chinese hamster V79 fibroblast cells were exposed to brief periods of cold but non-freezing temperatures at different points on the population growth curve. Upon rewarming, cells at the transition from logarithmic to stationary growth exhibited apoptosis (programmed cell death). Cells in other stages of growth, or after reentry into logarithmic growth by refeeding, did not exhibit apoptosis. Apoptosis was expressed by marked cytoplasmic blebbing, by a characteristic non-random fragmentation of DNA into nucleosomal-sized pieces, and by loss of colony-forming ability. The data suggest that cold shock served as a stimulus for susceptible cells to undergo apoptosis. Thus, the experiments describe a new in vitro system for studying the mechanisms of apoptosis.

  5. UO2 Grain Growth: Developing Phase Field Models for Pore Dragging, Solute Dragging and Anisotropic Grain Boundary Energies

    International Nuclear Information System (INIS)

    Ahmed, K.; Tonks, M.; Zhang, Y.; Biner, B.

    2016-01-01

    A detailed phase field model for the effect of pore drag on grain growth kinetics was implemented in MARMOT. The model takes into consideration both the curvature-driven grain boundary motion and pore migration by surface diffusion. As such, the model accounts for the interaction between pore and grain boundary kinetics, which tends to retard the grain growth process. Our 2D and 3D simulations demonstrate that the model capture all possible pore-grain boundary interactions proposed in theoretical models. For high enough surface mobility, the pores move along with the migrating boundary as a quasi-rigid-body, albeit hindering its migration rate compared to the pore-free case. For less mobile pores, the migrating boundary can separate from the pores. For the pore-controlled grain growth kinetics, the model predicts a strong dependence of the growth rate on the number of pores, pore size, and surface diffusivity in agreement with theroretical models. An evolution equation for the grain size that includes these parameters was derived and showed to agree well with numerical solution. It shows a smooth transition from boundary-controlled kinetics to pore-controlled kinetics as the surface diffusivity decreases or the number of pores or their size increases. This equation can be utilized in BISON to give accurate estimate for the grain size evolution. This will be accomplished in the near future. The effect of solute drag and anisotropy of grain boundary on grain growth will be investigated in future studies.

  6. Liquid phase epitaxial growth of silicon on porous silicon for photovoltaic applications

    International Nuclear Information System (INIS)

    Berger, S.; Quoizola, S.; Fave, A.; Kaminski, A.; Perichon, S.; Barbier, D.; Laugier, A.

    2001-01-01

    The aim of this experiment is to grow a thin silicon layer ( 2 atmosphere, and finally LPE silicon growth with different temperature profiles in order to obtain a silicon layer on the sacrificial porous silicon (p-Si). We observed a pyramidal growth on the surface of the (100) porous silicon but the coalescence was difficult to obtain. However, on a p-Si (111) oriented wafer, homogeneous layers were obtained. (orig.)

  7. Altering the cooling rate dependence of phase formation during rapid solidification in the Nd{sub 2}Fe{sub 14}B system

    Energy Technology Data Exchange (ETDEWEB)

    Branagan, D.J. [USDOE, Ames, IA (United States). Ames Lab.]|[Iowa State Univ. of Science and Technology, Ames, IA (United States). Dept. of Materials Science and Engineering; McCallum, R.W. [USDOE, Ames, IA (United States). Ames Lab.]|[Iowa State Univ. of Science and Technology, Ames, IA (United States). Dept. of Materials Science and Engineering

    1995-04-26

    In order to evaluate the effects of additions on the solidification behavior of Nd{sub 2}Fe{sub 14}B, a stoichiometric alloy was modified with elemental additions of Ti or C and a compound addition of Ti with C. For each alloy, a series of wheel speed runs was undertaken, from which the optimum wheel speeds and optimum energy products were determined. On the BH{sub max} versus wheel speed plots, regions were identified in order to analyze the changes with cooling rates leading to phase formation brought about by the alloy modifications. The compilation of the regional data of the modified alloys showed their effects on altering the cooling rate dependence of phase formation. It was found that the regions of properitectic iron formation, glass formation, and the optimum cooling rate can be changed by more than a factor of two through appropriate alloying additions. The effects of the alloy modifications can be visualized in a convenient fashion through the use of a model continuous cooling transformation (CCT) diagram which represents phase formation during the solidification process under continuous cooling conditions for a wide range of cooling rates from rapid solidification to equilibrium cooling. ((orig.)).

  8. Development and validation of a rapid reversed-phase HPLC method for the determination of the non-nucleoside reverse transcriptase inhibitor dapivirine from polymeric nanoparticles.

    Science.gov (United States)

    das Neves, José; Sarmento, Bruno; Amiji, Mansoor M; Bahia, Maria Fernanda

    2010-06-05

    The objective of this work was to develop and validate a rapid reversed-phase (RP) high-performance liquid chromatography (HPLC) method for the in vitro pharmaceutical characterization of dapivirine-loaded polymeric nanoparticles. Chromatographic runs were performed on a RP C18 column with a mobile phase comprising acetonitrile-0.5% (w/v) triethanolamine solution in isocratic mode (80:20, v/v) at a flow rate of 1 ml/min. Dapivirine was detected at a wavelength of 290 nm. The method was shown to be specific, linear in the range of 1-50 microg/ml (R(2)=0.9998), precise at the intra-day and inter-day levels as reflected by the relative standard deviation values (less than 0.85%), accurate (recovery rate of 100.17+/-0.35%), and robust to changes in the mobile phase and column brand. The detection and quantitation limits were 0.08 and 0.24 microg/ml, respectively. The method was successfully used to determine the loading capacity and association efficiency of dapivirine in poly(lactic-co-glycolic acid)-based nanoparticles and its in vitro release. Copyright (c) 2010 Elsevier B.V. All rights reserved.

  9. Rapid cell cycle analysis by measurement of the radioactivity per cell in a narrow window in S phase (RCSsub(i))

    International Nuclear Information System (INIS)

    Gray, J.W.; Carver, J.H.; George, Y.S.; Mendelsohn, M.L.

    1977-01-01

    A new rapid method for the cell cycle analysis of asynchronously growing cells is presented. The new method is an alternative to the more time consuming and subjective fraction of labeled mitoses (FLM) method. Like the FLM method, all cells in the S phase of the cell cycle are marked by pulse labeling with a radioactive DNA precursor. The subsequent progress of the cohort of cells thus labeled is monitored through a narrow window in the cell cycle. The window is defined by a narrow range of DNA contents corresponding to cells in mid-S phase and is designated Ssub(i). The cellular DNA content is measured by flow cytometry and the cells in the window Ssub(i) are selected by electronic cell sorting. The radioactivity per cell in Ssub(i) (RCSsub(i)) is determined by liquid scintillation counting. The duration of S phase and of the total cycle and the dispersions therein are determined from the oscillation of the RCSsub(i) values with time. The complete cell cycle analysis can be accomplished in as little as 1 day following the collection of samples. Exponentially growing Chinese hamster ovary (CHO) cells were analyzed according to the RCSsub(i) method and the FLM method. It is demonstrated that the two techniques give essentially the same results. (author)

  10. A simple, sensitive and rapid isocratic reversed-phase high-performance liquid chromatography method for determination and stability study of curcumin in pharmaceutical samples

    Science.gov (United States)

    Amanolahi, Farjad; Mohammadi, Ali; Kazemi Oskuee, Reza; Nassirli, Hooriyeh; Malaekeh-Nikouei, Bizhan

    2017-01-01

    Objective: This study was designed to develop and validate a new reversed-phase high-performance liquid chromatography (RP-HPLC) method based on Q2 (R1) International Conference on Harmonization (ICH) guideline for determination of curcumin in pharmaceutical samples. Materials and Methods: The HPLC instrument method was optimized with isocratic elution with acetonitrile: ammonium acetate (45:55, v/v, pH 3.5), C18 column (150 mm×4.6 mm×5 µm particle size) and a flow rate of 1 ml/min in ambient condition and total retention time of 17 min. The volume of injection was set at 20 µl and detection was recorded at 425 nm. The robustness of the method was examined by changing the mobile phase composition, mobile phase pH, and flow rate. Results: The method was validated with respect to precision, accuracy and linearity in a concentration range of 2-100 µg/ml. The limit of detection (LOD) and limit of quantification (LOQ) were 0.25 and 0.5 µg/ml, respectively. The percentage of recovery was 98.9 to 100.5 with relative standard deviation (RSD) < 0.638%. Conclusion: The method was found to be simple, sensitive and rapid for determination of curcumin in pharmaceutical samples and had enough sensitivity to detect degradation product of curcumin produced under photolysis and hydrolysis stress condition. PMID:29062806

  11. Direct observation of the phase space footprint of a painting injection in the Rapid Cycling Synchrotron at the Japan Proton Accelerator Research Complex

    Directory of Open Access Journals (Sweden)

    P. K. Saha

    2009-04-01

    Full Text Available The 3 GeV Rapid Cycling Synchrotron (RCS at Japan Proton Accelerator Research Complex is nearly at the operational stage with regard to the beam commissioning aspects. Recently, the design painting injection study has been commenced with the aim of high output beam power at the extraction. In order to observe the phase space footprint of the painting injection, a method was developed utilizing a beam position monitor (BPM in the so-called single pass mode. The turn-by-turn phase space coordinates of the circulating beam directly measured using a pair of BPMs entirely positioned in drift space, and the calculated transfer matrices from the injection point to the pair of BPMs with several successive turns were used together in order to obtain the phase space footprint of the painting injection. There are two such pairs of BPMs placed in two different locations in the RCS, the results from which both agreed and were quite consistent with what was expected.

  12. Direct observation of the phase space footprint of a painting injection in the Rapid Cycling Synchrotron at the Japan Proton Accelerator Research Complex

    Science.gov (United States)

    Saha, P. K.; Shobuda, Y.; Hotchi, H.; Hayashi, N.; Takayanagi, T.; Harada, H.; Irie, Y.

    2009-04-01

    The 3 GeV Rapid Cycling Synchrotron (RCS) at Japan Proton Accelerator Research Complex is nearly at the operational stage with regard to the beam commissioning aspects. Recently, the design painting injection study has been commenced with the aim of high output beam power at the extraction. In order to observe the phase space footprint of the painting injection, a method was developed utilizing a beam position monitor (BPM) in the so-called single pass mode. The turn-by-turn phase space coordinates of the circulating beam directly measured using a pair of BPMs entirely positioned in drift space, and the calculated transfer matrices from the injection point to the pair of BPMs with several successive turns were used together in order to obtain the phase space footprint of the painting injection. There are two such pairs of BPMs placed in two different locations in the RCS, the results from which both agreed and were quite consistent with what was expected.

  13. Milk production and composition, and progeny performance in young ewes with high merit for rapid growth and muscle and fat accumulation.

    Science.gov (United States)

    Rosales Nieto, C A; Ferguson, M B; Macleay, C A; Briegel, J R; Wood, D A; Martin, G B; Bencini, R; Thompson, A N

    2018-02-26

    In ewe lambs, acceleration of growth and accumulation of both muscle and fat leads to earlier sexual maturity and better reproductive performance. The next stage in the development of this theme is to test whether these aspects of growth in young ewes affect milk production in their first lactation and the growth of their first progeny. We studied 75 young Merino ewes that had known phenotypic values for depth of eye muscle (EMD) and fat (FAT), and known Australian Sheep Breeding Values for post-weaning weight (PWT) and depths of eye muscle (PEMD) and fat (PFAT). They lambed for the first time at 1 year of age. Their lambs were weighed weekly from birth to weaning at 10 weeks to determine live weight gain and weaning weight. Progeny birth weight was positively associated with live weight gain and weaning weight (P0.05). The PWT of the sire was positively associated with live weight gain (P0.05). The concentrations of fat, protein, lactose and total solids in the milk were not affected by the phenotype or genotype of the mothers or of the sires of the mothers, or by the sex of the progeny (P>0.05). We conclude that selection of young Merino ewes for better growth, and more rapid accumulation of muscle and fat, will lead to progeny that are heavier at birth, grow faster and are heavier at weaning. Moreover, milk production and composition do not seem to be affected by the genetic merit of the mother for post-weaning live weight or PEMD or PFAT. Therefore, Merino ewes can lamb at 1 year of age without affecting the production objectives of the Merino sheep industry.

  14. Better to light a candle than curse the darkness: illuminating spatial localization and temporal dynamics of rapid microbial growth in the rhizosphere

    Directory of Open Access Journals (Sweden)

    Patrick M Herron

    2013-09-01

    Full Text Available The rhizosphere is a hotbed of microbial activity in ecosystems, fueled by carbon compounds from plant roots. Basic questions about the location and dynamics of plant-spurred microbial growth in the rhizosphere are difficult to answer with standard, destructive soil assays mixing a multitude of microbe-scale microenvironments in a single, often sieved, sample. Soil microbial biosensors designed with the luxCDABE reporter genes fused to a promoter of interest enable continuous imaging of the microbial perception of (and response to environmental conditions in soil. We used the common soil bacterium Pseudomonas putida KT2440 as host to plasmid pZKH2 containing a fusion between the strong constituitive promoter nptII and luxCDABE (coding for light-emitting proteins from Vibrio fischeri. Experiments in liquid media demonstrated that high light production by KT2440/pZKH2 was associated with rapid microbial growth supported by high carbon availability. We applied the biosensors in microcosms filled with non-sterile soil in which corn (Zea mays L., black poplar (Populus nigra L. or tomato (Solanum lycopersicum L. was growing. We detected minimal light production from microbiosensors in the bulk soil, but biosensors reported continuously from around roots for as long as six days. For corn, peaks of luminescence were detected 1-4 and 20-35 mm along the root axis behind growing root tips, with the location of maximum light production moving farther back from the tip as root growth rate increased. For poplar, luminescence around mature roots increased and decreased on a coordinated diel rhythm, but was not bright near root tips. For tomato, luminescence was dynamic, but did not exhibit a diel rhythm, appearing in acropetal waves along roots. KT2440/pZKH2 revealed that root tips are not always the only, or even the dominant, hotspots for rhizosphere microbial growth, and carbon availability is highly variable in space and time around roots.

  15. Automated Method for the Rapid and Precise Estimation of Adherent Cell Culture Characteristics from Phase Contrast Microscopy Images

    Science.gov (United States)

    Jaccard, Nicolas; Griffin, Lewis D; Keser, Ana; Macown, Rhys J; Super, Alexandre; Veraitch, Farlan S; Szita, Nicolas

    2014-01-01

    The quantitative determination of key adherent cell culture characteristics such as confluency, morphology, and cell density is necessary for the evaluation of experimental outcomes and to provide a suitable basis for the establishment of robust cell culture protocols. Automated processing of images acquired using phase contrast microscopy (PCM), an imaging modality widely used for the visual inspection of adherent cell cultures, could enable the non-invasive determination of these characteristics. We present an image-processing approach that accurately detects cellular objects in PCM images through a combination of local contrast thresholding and post hoc correction of halo artifacts. The method was thoroughly validated using a variety of cell lines, microscope models and imaging conditions, demonstrating consistently high segmentation performance in all cases and very short processing times (image). Based on the high segmentation performance, it was possible to precisely determine culture confluency, cell density, and the morphology of cellular objects, demonstrating the wide applicability of our algorithm for typical microscopy image processing pipelines. Furthermore, PCM image segmentation was used to facilitate the interpretation and analysis of fluorescence microscopy data, enabling the determination of temporal and spatial expression patterns of a fluorescent reporter. We created a software toolbox (PHANTAST) that bundles all the algorithms and provides an easy to use graphical user interface. Source-code for MATLAB and ImageJ is freely available under a permissive open-source license. Biotechnol. Bioeng. 2014;111: 504–517. © 2013 Wiley Periodicals, Inc. PMID:24037521

  16. Rapid method for determination of glyphosate in groundwater using high performance liquid chromatography and solid-phase extraction after derivatization

    Directory of Open Access Journals (Sweden)

    Valdir Eduardo Olivo

    2015-04-01

    Full Text Available The intensive use of pesticides in agriculture has prompted researchers to develop new methods for identifying these pollutants in water. This study sought to validate a high performance liquid chromatography (HPLC method to determine the concentration of the pesticide glyphosate in groundwater samples by using solid-phase extraction (SPE filters after derivatization with chloroformate 9-fluorenylmethoxycarbonyl (FMOC-Cl. For the HPLC method, we evaluated the following main validation parameters: linearity, specificity, precision, accuracy, robustness, and limits of detection and quantification. After validation of the method, we determined the concentration of glyphosate in samples from thirteen deep, tubular wells distributed in urban and rural areas in Chapecó, SC, Brazil. The solvent used in the extraction of excess FMOC-Cl was dichloromethane and subsequently filtration was performed on C18 SPE, and injected into the chromatograph column in amino polymer with fluorescence detection. The analytical curve made in ultrapure water was linear, with a correlation coefficient of 0.99. The limits of detection and quantification were 0.24 and 0.07 µg L-1, respectively. Recovery tests in natural waters ranged from 90.37 to 101.70%. Glyphosate was detected in 5 of the thirteen wells evaluated. The highest concentration of glyphosate (6.80 µg L-1 was detected in a countryside well, near the municipal water supply. Despite the low levels of glyphosate detected in our study, any amount present in groundwater samples is worrisome, as these molecules have low ground mobility.

  17. Growth Kinetics of Laves Phase and Its Effect on Creep Rupture Behavior in 9Cr Heat Resistant Steel

    Institute of Scientific and Technical Information of China (English)

    Zhi-xin XIA; Chuan-yang WANG; Chen LEI; Yun-ting LAI; Yan-fen ZHAO; Lu ZHANG

    2016-01-01

    The effects of Laves phase formation and growth on creep rupture behaviors of P92 steel at 883 K were studied.The microstructural evolution was characterized using scanning electron microscopy and transmission elec-tron microscopy.Kinetic modeling was carried out using the software DICTRA.The results indicated Fe2 (W,Mo) Laves phase has formed during creep with 200 MPa applied stress at 883 K for 243 h.The experimental results showed a good agreement with thermodynamic calculations.The plastic deformation of laths is the main reason of creep rupture under the applied stress beyond 160 MPa,whereas,creep voids initiated by coarser Laves phase play an effective role in creep rupture under the applied stress lower than 160 MPa.Laves phase particles with the mean size of 243 nm lead to the change of creep rupture feature.Microstructures at the vicinity of fracture surface,the gage portion and the threaded ends of creep rupture specimens were also observed,indicating that creep tensile stress enhances the coarsening of Laves phase.

  18. Body composition and energetic efficiency in two lines of mice selected for rapid growth rate and their F1 crosses.

    Science.gov (United States)

    Eisen, E J; Bakker, H; Nagai, J

    1977-01-01

    Correlated responses to selection for increased growth rate were compared in two mouse populations (M16 and H6) of distinct genetic origin. Traits studied were body composition, feed intake, constituent gains and energetic efficiency. When compared with their respective controls (ICR and C2) at 6 and 9 weeks of age, body weight increased more in M16 (57%and 69 % of the control mean) than in H6 (40 % and 34%). The M16 showed correlated responses in fat percent of 2.6% (P .05). The correlated responses in fat percent were 2.7 and 4.7 times higher in M16 than H6 at 6 and 9 weeks. The regression of ln fat weight on ln empty body weight was larger in M16 (P calories and ash; fat and caloric gain and efficiency exhibited higher correlated responses in M16 than H6. During the 6- to 9-week interval, the M16 population continued to evince positive correlated responses in gains and efficiencies of fat, protein and calories, whereas H6 did not. Several possible explanations are presented to account for the differences in correlated responses between the selected populations. Partitioning of correlated response differences between M16 and H6 into average direct and average maternal genetic effects indicated that average direct genetic effects, favoring M16, were responsible for the major difference between the selected populations. Direct heterosis in F1 crosses of the selected populations were generally not significant, although there was a tendency for fat percent and fat weight to show heterosis.

  19. Collagen-embedded hydroxylapatite-beta-tricalcium phosphate-silicon dioxide bone substitute granules assist rapid vascularization and promote cell growth

    Energy Technology Data Exchange (ETDEWEB)

    Ghanaati, Shahram M; Thimm, Benjamin W; Unger, Ronald E; Orth, Carina; Barbeck, Mike; Kirkpatrick, C James [Institute of Pathology, Johannes Gutenberg-University Mainz, Langenbeckstr.1, 55101 Mainz (Germany); Kohler, Thomas; Mueller, Ralph, E-mail: ghanaati@uni-mainz.d [Institute for Biomechanics, ETH Zuerich, Wolfgang-Pauli-Str.10, 8093 Zuerich (Switzerland)

    2010-04-15

    In the present study we assessed the biocompatibility in vitro and in vivo of a low-temperature sol-gel-manufactured SiO{sub 2}-based bone graft substitute. Human primary osteoblasts and the osteoblastic cell line, MG63, cultured on the SiO{sub 2} biomatrix in monoculture retained their osteoblastic morphology and cellular functionality in vitro. The effect of the biomaterial in vivo and its vascularization potential was tested subcutaneously in Wistar rats and demonstrated both rapid vascularization and good integration within the peri-implant tissue. Scaffold degradation was progressive during the first month after implantation, with tartrate-resistant acid phosphatase-positive macrophages being present and promoting scaffold degradation from an early stage. This manuscript describes successful osteoblastic growth promotion in vitro and a promising biomaterial integration and vasculogenesis in vivo for a possible therapeutic application of this biomatrix in future clinical studies.

  20. Heat-shock induction of ionizing radiation resistance in Saccharomyces cerevisiae, and the correlation with stationary growth phase

    International Nuclear Information System (INIS)

    Mitchel, R.E.J.; Morrison, D.P.

    1982-01-01

    Radiation resistance and thermal resistance vary as a function of culture temperature in logarithmically growing Saccharomyces cerevisiae and are related to the optimum temperature for growth. Radiation resistance and thermal resistance were also induced when cells grown at low temperatures were subjected to a heat shock at or above the optimum growth temperature. Exposure to ionizing radiation followed by a short incubation at low temperature also induced resistance to killing by heat. Heat-shocked cells are induced to a level of thermal and radioresistance much greater than the characteristic resistance level of cells grown continuously at the shock temperature. This high level of resistance, which resembles that of stationary-phase cells, decays to the characteristic log-phase level within one doubling of cell number after the heat shock. Both induction of resistance and decay of that induction require protein synthesis. It is postulated that induction of resistance by heat shock or ionizing radiation is a response of the cells to stress and represents a preparation to enter stationary phase

  1. Redundancy and molecular evolution: the rapid Induction of bone formation by the mammalian transforming growth factor-β3 isoform

    Directory of Open Access Journals (Sweden)

    Ugo Ripamonti

    2016-09-01

    Full Text Available The soluble osteogenic molecular signals of the transforming growth factor-β (TGF-β supergene family are the molecular bases of the induction of bone formation and postnatal bone tissue morphogenesis with translation into clinical contexts. The mammalian TGF-β3 isoform, a pleiotropic member of the family, controls a vast array of biological processes including the induction of bone formation. Recombinant hTGF-β3 induces substantial bone formation when implanted with either collagenous bone matrices or coral-derived macroporous bioreactors in the rectus abdominis muscle of the non-human primate Papio ursinus. In marked contrast, the three mammalian TGF-βs do not initiate the induction of bone formation in rodents and lagomorphs. The induction of bone by hTGF-β3/preloaded bioreactors is orchestrated by inducing fibrin-fibronectin rings that structurally organize tissue patterning and morphogenesis within the macroporous spaces. Induced advancing extracellular matrix rings provide the structural anchorage for hyper chromatic cells, interpreted as differentiating osteoblasts re-programmed by hTGF-β3 from invading myoblastic and/or pericytic differentiated cells. Runx2 and Osteocalcin expression are significantly up-regulated correlating to multiple invading cells differentiating into the osteoblastic phenotype. Bioreactors pre-loaded with recombinant human Noggin (hNoggin, a BMPs antagonist, show down-regulation of BMP-2 and other profiled osteogenic proteins’ genes resulting in minimal bone formation. Coral-derived macroporous constructs preloaded with binary applications of hTGF-β3 and hNoggin also show down-regulation of BMP-2 with the induction of limited bone formation. The induction of bone formation by hTGF-β3 is via the BMPs pathway and it is thus blocked by hNoggin. Our systematic studies in Papio ursinus with translational hTGF-β3 in large cranio-mandibulo-facial defects in humans are now requesting the re-evaluation of Bone

  2. Rapid determination of six carcinogenic primary aromatic amines in mainstream cigarette smoke by two-dimensional online solid phase extraction combined with liquid chromatography tandem mass spectrometry.

    Science.gov (United States)

    Bie, Zhenying; Lu, Wei; Zhu, You; Chen, Yusong; Ren, Hubo; Ji, Lishun

    2017-01-27

    A fully automated, rapid, and reliable method for simultaneous determination of six carcinogenic primary aromatic amines (AAs), including o-toluidine (o-TOL), 2, 6-dimethylaniline (2, 6-DMA), o-anisidine (o-ASD), 1-naphthylamine (1-ANP), 2-naphthylamine (2-ANP), and 4-aminobiphenyl (4-ABP), in mainstream cigarette smoke was established. The proposed method was based on two-dimensional online solid phase extraction combined with liquid chromatography tandem mass spectrometry (SPE/LC-MS/MS). The particulate phase of the mainstream cigarette smoke was collected on a Cambridge filter pad and pretreated via ultrasonic extraction with 2% formic acid (FA), while the gas phase was trapped by 2% FA without pretreatment for determination. The two-dimensional online SPE comprised of two cartridges with different absorption characteristics was applied for sample pretreatment. Analysis was performed by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) under multiple reaction monitoring mode. Each sample required about 0.5h for solid phase extraction and analysis. The limit of detections (LODs) for six AAs ranged from 0.04 to 0.58ng/cig and recoveries were within 84.5%-122.9%. The relative standard deviations of intra- and inter-day tests for 3R4F reference cigarette were less than 6% and 7%, respectively, while no more than 7% and 8% separately for a type of Virginia cigarette. The proposed method enabled minimum sample pretreatment, full automation, and high throughput with high selectivity, sensitivity, and accuracy. As a part of the validation procedure, fifteen brands of cigarettes were tested by the designed method. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Rapid magnetic solid-phase extraction based on monodisperse magnetic single-crystal ferrite nanoparticles for the determination of free fatty acid content in edible oils.

    Science.gov (United States)

    Wei, Fang; Zhao, Qin; Lv, Xin; Dong, Xu-Yan; Feng, Yu-Qi; Chen, Hong

    2013-01-09

    This study proposes a rapid magnetic solid-phase extraction (MSPE) based on monodisperse magnetic single-crystal ferrite (Fe(3)O(4)) nanoparticles (NPs) for determining the quantities of eight free fatty acids (FFAs), including palmitic acid (C16:0), stearic acid (C18:0), oleic acid (C18:1), linoleic acid (C18:2), linolenic acid (C18:3), arachidic acid (C20:0), eicosenoic acid (C20:1), and behenic acid (C22:0) in oil. The amine-functionalized mesoporous Fe(3)O(4) magnetic NPs were applied as a sorbent for MSPE of FFAs from oil samples in a process that is based on hydrophilic interaction. The extraction can be completed rapidly in a dispersive mode with the aid of vigorous vortex. Additional tedious processing steps such as centrifugation and evaporation of organic solvent were not necessary with this procedure. Furthermore, esterification of FFAs can be accomplished during the desorption procedure by using methanol/sulfuric acid (99:1, v/v) as the desorption solvent. Several parameters affecting the extraction efficiency were investigated, including the matrix solvent for extraction, the desorption solvent and desorption time, and the amount of sorbent and extraction time. The pretreatment process was rapid under optimal conditions, being accomplished within 15 min. When coupled with gas chromatography-flame ionization detection (GC-FID), a rapid, simple, and convenient MSPE-GC-FID method for the determination of FFAs in oil samples was established with a total analysis time within 25 min. The limits of detection for the target FFAs were found to be 7.22-26.26 ng/mL. Recoveries in oil samples were in the range of 81.33-117.75%, with RSDs of <6.4% (intraday) and <6.9% (interday). This method was applied successfully to the analysis of dynamic FFA formation in four types of edible oils subjected to an accelerated storage test. The simple, rapid, and cost-effective method developed in the current study offers a potential application for the extraction and

  4. Safe communities in China as a strategy for injury prevention and safety promotion programmes in the era of rapid economic growth.

    Science.gov (United States)

    Wang, Shu-Mei; Dalal, Koustuv

    2013-02-01

    Due to its rapid economic development, China is facing a huge health, social, and economic burden resulting from injuries. The study's objective was to examine Safe Communities in China as a strategy for injury prevention and safety promotion programmes in the era of rapid economic growth. Literature searches in English and Chinese, which included grey literature, were performed on the Chinese Journal Full-text Search System and Medline, using the words "Safe Community", "injury", "economics", and "prevention". The results showed that the existing 35 recognized members of the International Safe Community Network have not placed due emphasis on suicide prevention, which is one of the leading problems in both rural and urban China. A few groups, such as children, the elderly, cyclists, and pedestrians, have received due emphasis, while other vulnerable groups, such as migrant workers, motorcyclists, students, players, and farmers have not received the necessary attention from the Safe Community perspective. As the evidence describes, Safe Communities in China can be a very effective strategy for injury prevention, but four aspects need to be strengthened in the future: (1) establish and strengthen the policy and regulations in terms of injury prevention at the national level; (2) create a system to involve professional organizations and personnel in projects; (3) consider the economic development status of different parts of China; and (4) intentional injury prevention should receive greater attention.

  5. Direct in Situ Conversion of Metals into Metal-Organic Frameworks: A Strategy for the Rapid Growth of MOF Films on Metal Substrates.

    Science.gov (United States)

    Ji, Hoon; Hwang, Sunhyun; Kim, Keonmok; Kim, CheolGi; Jeong, Nak Cheon

    2016-11-30

    The fabrication of metal-organic framework (MOF) films on conducting substrates has demonstrated great potential in applications such as electronic conduction and sensing. For these applications, direct contact of the film to the conducting substrate without a self-assembled monolayer (SAM) is a desired step that must be achieved prior to the use of MOF films. In this report, we propose an in situ strategy for the rapid one-step conversion of Cu metal into HKUST-1 films on conducting Cu substrates. The Cu substrate acts both as a conducting substrate and a source of Cu 2+ ions during the synthesis of HKUST-1. This synthesis is possible because of the simultaneous reaction of an oxidizing agent and a deprotonating agent, in which the former agent dissolves the metal substrate to form Cu 2+ ions while the latter agent deprotonates the ligand. Using this strategy, the HKUST-1 film could not only be rapidly synthesized within 5 min but also be directly attached to the Cu substrate. Based on microscopic studies, we propose a plausible mechanism for the growth reaction. Furthermore, we show the versatility of this in situ conversion methodology, applying it to ZIF-8, which comprises Zn 2+ ions and imidazole-based ligands. Using an I 2 -filled HKUST-1 film, we further demonstrate that the direct contact of the MOF film to the conducting substrate makes the material more suitable for use as a sensor or electronic conductor.

  6. Rapid Development and Validation of Improved Reversed-Phase High-performance Liquid Chromatography Method for the Quantification of Mangiferin, a Polyphenol Xanthone Glycoside in Mangifera indica.

    Science.gov (United States)

    Naveen, P; Lingaraju, H B; Prasad, K Shyam

    2017-01-01

    Mangiferin, a polyphenolic xanthone glycoside from Mangifera indica , is used as traditional medicine for the treatment of numerous diseases. The present study was aimed to develop and validate a reversed-phase high-performance liquid chromatography (RP-HPLC) method for the quantification of mangiferin from the bark extract of M. indica . RP-HPLC analysis was performed by isocratic elution with a low-pressure gradient using 0.1% formic acid: acetonitrile (87:13) as a mobile phase with a flow rate of 1.5 ml/min. The separation was done at 26°C using a Kinetex XB-C18 column as stationary phase and the detection wavelength at 256 nm. The proposed method was validated for linearity, precision, accuracy, limit of detection, limit of quantification, and robustness by the International Conference on Harmonisation guidelines. In linearity, the excellent correlation coefficient more than 0.999 indicated good fitting of the curve and also good linearity. The intra- and inter-day precision showed high reliability and reproducibility of the method. The recovery values at three different levels (50%, 100%, and 150%) of spiked samples were found to be 100.47, 100.89, and 100.99, respectively, and low standard deviation value high accuracy of the method. In robustness, the results remain unaffected by small variation in the analytical parameters, which shows the robustness of the method. Liquid chromatography-mass spectrometry analysis confirmed the presence of mangiferin with M/Z value of 421. The assay developed by HPLC method is a simple, rapid, and reliable for the determination of mangiferin from M. indica . The present study was intended to develop and validate an RP-HPLC method for the quantification of mangiferin from the bark extract of M. indica . The developed method was validated for linearity, precision, accuracy, limit of detection, limit of quantification and robustness by International Conference on Harmonization guidelines. This study proved that the developed

  7. Analysis of expression profile of mce operon genes (mce1, mce2, mce3 operon) in different Mycobacterium tuberculosis isolates at different growth phases.

    Science.gov (United States)

    Singh, Pratibha; Katoch, V M; Mohanty, K K; Chauhan, Devendra Singh

    2016-04-01

    Mycobacterium tuberculosis (M. tuberculosis) has four homologous mammalian cell entry (mce) operons (mce1-4) that encode exported proteins and have a possible role in the virulence mechanism of this pathogen. The expression of mce operon is considered to be complex and not completely understood. Although expression of mce operon at different in vitro growth phases has been studied earlier, its expression in different M. tuberculosis isolates under different growth phases is not yet studied. The present preliminary study was conducted on a limited number of isolates to know the trend of expression pattern of mce operon genes in different M. tuberculosis isolates under different growth stages. In this study, we monitored the transcriptional profile of selected mce operon genes (mce1A, mce1D, mce2A, mce2D, mce3A, mce3C) in different M.tuberculosis isolates (MDR1, MDR2, and sensitive isolate) at early exponential and stationary phases using real-time quantitative PCR. The expression ratio of all selected mce operon genes in all M. tuberculosis isolates was reduced at the initial phase and increased substantially at a later phase of growth. Higher expression of mce1 operon genes was found in all M. tuberculosis isolates as compared to other mce operon genes (mce2 and mce3 operons) at stationary growth phase. the higher expression of mce operon genes at stationary phase (as compared to early exponential phase) suggested growth phase dependent expression of mce operon genes. This indicated that the mce operon genes might have a role in M. tuberculosis survival and adaptation on the onset of adverse condition like stationary phase. Identification of differentially expressed genes will add to our understanding of the bacilli involved in adaptation to different growth conditions.

  8. Growth of ruby crystals by the heat exchanger method, phase 1: NSF small business innovation research

    Science.gov (United States)

    Schmid, F.; Khattak, C. P.

    1980-03-01

    Conditions for the growth of large, uniformly doped laser crystals by the heat exchanger method are explored. Determination of the melt point, selection of crucible material and establishment of furnace operating parameters are discussed. The melt point of ruby was found to be 2040 plus or minus 10 C. Molybdenum crucibles can be used to contain ruby in vacuum as well as under argon atmospheres at desired superheat temperatures over extended periods required for crystal growth. Thermodynamic analysis was conducted and vapor pressures of volatile species calculated. Experimentally, volatilization of chromium oxides was suppressed by using welded covers on crucibles and operating under an argon pressure in the furnace.

  9. Ductile-phase toughening and fatigue crack growth in Nb3Al base alloys

    International Nuclear Information System (INIS)

    Gnanamoorthy, R.; Hanada, S.

    1996-01-01

    Niobium aluminide (Nb 3 Al) base intermetallic compounds exhibit good high-temperature strength and creep properties and potential for applications above 1,200 C provided their inadequately low room-temperature ductility, fracture toughness and fatigue crack growth behavior are improved. Addition of tantalum to Nb 3 Al base materials improves the high-temperature strength significantly and seems to be a potential alloying element. In the present study, room temperature fracture toughness and fatigue crack growth behavior of tantalum alloyed Nb 3 Al base alloy prepared by ingot metallurgy are investigated

  10. Rapid determination of trace nitrophenolic organics in water by combining solid-phase extraction with surface-assisted laser desorption/ionization time-of-flight mass spectrometry.

    Science.gov (United States)

    Chen, Y C; Shiea, J; Sunner, J

    2000-01-01

    A rapid technique for the screening of trace compounds in water by combining solid-phase extraction (SPE) with activated carbon surface-assisted laser desorption/ionization (SALDI) time-of-flight mass spectrometry is demonstrated. Activated carbon is used both as the sorbent in SPE and as the solid in the SALDI matrix system. This eliminates the need for an SPE elution process. After the analytes have been adsorbed on the surfaces of the activated carbon during SPE extraction, the activated carbon is directly mixed with the SALDI liquid and mass spectrometric analysis is performed. Trace phenolic compounds in water were used to demonstrate the effectiveness of the method. The detection limit for these compounds is in the ppb to ppt range. Copyright 2000 John Wiley & Sons, Ltd.

  11. Rapid screening of selective serotonin re-uptake inhibitors in urine samples using solid-phase microextraction gas chromatography-mass spectrometry.

    Science.gov (United States)

    Salgado-Petinal, Carmen; Lamas, J Pablo; Garcia-Jares, Carmen; Llompart, Maria; Cela, Rafael

    2005-07-01

    In this paper a solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) method is proposed for a rapid analysis of some frequently prescribed selective serotonin re-uptake inhibitors (SSRI)-venlafaxine, fluvoxamine, mirtazapine, fluoxetine, citalopram, and sertraline-in urine samples. The SPME-based method enables simultaneous determination of the target SSRI after simple in-situ derivatization of some of the target compounds. Calibration curves in water and in urine were validated and statistically compared. This revealed the absence of matrix effect and, in consequence, the possibility of quantifying SSRI in urine samples by external water calibration. Intra-day and inter-day precision was satisfactory for all the target compounds (relative standard deviation, RSD, detection limits achieved were detected and tentatively identified.

  12. A rapid MCM-41 dispersive micro-solid phase extraction coupled with LC/MS/MS for quantification of ketoconazole and voriconazole in biological fluids.

    Science.gov (United States)

    Yahaya, Noorfatimah; Sanagi, Mohd Marsin; Abd Aziz, Noorizan; Wan Ibrahim, Wan Aini; Nur, Hadi; Loh, Saw Hong; Kamaruzaman, Sazlinda

    2017-02-01

    A rapid dispersive micro-solid phase extraction (D-μ-SPE) combined with LC/MS/MS method was developed and validated for the determination of ketoconazole and voriconazole in human urine and plasma samples. Synthesized mesoporous silica MCM-41 was used as sorbent in d-μ-SPE of the azole compounds from biological fluids. Important D-μ-SPE parameters, namely type desorption solvent, extraction time, sample pH, salt addition, desorption time, amount of sorbent and sample volume were optimized. Liquid chromatographic separations were carried out on a Zorbax SB-C 18 column (2.1 × 100 mm, 3.5 μm), using a mobile phase of acetonitrile-0.05% formic acid in 5 mm ammonium acetate buffer (70:30, v/v). A triple quadrupole mass spectrometer with positive ionization mode was used for the determination of target analytes. Under the optimized conditions, the calibration curves showed good linearity in the range of 0.1-10,000 μg/L with satisfactory limit of detection (≤0.06 μg/L) and limit of quantitation (≤0.3 μg/L). The proposed method also showed acceptable intra- and inter-day precisions for ketoconazole and voriconazole from urine and human plasma with RSD ≤16.5% and good relative recoveries in the range 84.3-114.8%. The MCM-41-D-μ-SPE method proved to be rapid and simple and requires a small volume of organic solvent (200 μL); thus it is advantageous for routine drug analysis. Copyright © 2016 John Wiley & Sons, Ltd.

  13. Temperature dependence of InN growth on (0001) sapphire substrates by atmospheric pressure hydride vapor phase epitaxy

    International Nuclear Information System (INIS)

    Kumagai, Yoshinao; Adachi, Hirokazu; Otake, Aya; Higashikawa, Yoshihiro; Togashi, Rie; Murakami, Hisashi; Koukitu, Akinori

    2010-01-01

    The temperature dependence of InN growth on (0001) sapphire substrates by atmospheric pressure hydride vapor phase epitaxy (HVPE) was investigated. N-polarity single-crystal InN layers were successfully grown at temperatures ranging from 400 to 500 C. The a and c lattice constants of InN layers grown at 450 C or below were slightly larger than those of InN layers grown above 450 C due to oxygen incorporation that also increased the carrier concentration. The optical absorption edge of the InN layer decreased from above 2.0 to 0.76 eV when the growth temperature was increased from 450 to 500 C. (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  14. A simple method for point-of-need extraction, concentration and rapid multi-mycotoxin immunodetection in feeds using aqueous two-phase systems.

    Science.gov (United States)

    Soares, Ruben R G; Azevedo, Ana M; Fernandes, Pedro; Chu, Virginia; Conde, João P; Aires-Barros, M Raquel

    2017-08-18

    The rapid detection of mycotoxins in feed samples is becoming an increasingly relevant challenge for the food production sector, in order to effectively enforce current regulations and assure food and feed safety. To achieve rapid mycotoxin detection, several biosensing strategies have been published, many reaching assay times of the order of a few minutes. However, the vast majority of these rely on sample preparation based on volatile organic solvents, often comprising complex multi-step procedures and devoid of clean-up and/or concentration effects. Here, a novel sample preparation methodology based on a green, non-toxic and inexpensive polyethylene glycol-sodium citrate aqueous two-phase system is reported, providing single-step extraction and concentration of three target mycotoxins within 20min: aflatoxin B1 (AFB1), ochratoxin A (OTA) and deoxynivalenol (DON). With point-of-need applications in mind, the extraction procedure was optimized and validated using a rapid multi-toxin microfluidic competitive immunoassay. The assay was successfully tested with spiked complex solid matrices including corn, soy, chickpea and sunflower-based feeds and limits of detection of 4.6ngg -1 ±15.8%, 24.1ngg -1 ±8.1% and 129.7ngg -1 ±53.1% (±CV) were obtained in corn for AFB1, OTA and DON, respectively. These sensitivities are fit-for-purpose at the required regulatory and recommended limits for animal feed, providing an effective and safe semi-quantitative mycotoxin analysis that can be performed in the field. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Rapid solid-phase extraction method to quantify [11C]-verapamil, and its [11C]-metabolites, in human and macaque plasma

    International Nuclear Information System (INIS)

    Unadkat, Jashvant D.; Chung, Francisco; Sasongko, Lucy; Whittington, Dale; Eyal, Sara; Mankoff, David; Collier, Ann C.; Muzi, Mark; Link, Jeanne

    2008-01-01

    Introduction: P-glycoprotein (P-gp), an efflux transporter, is a significant barrier to drug entry into the brain and the fetus. The positron emission tomography (PET) ligand, [ 11 C]-verapamil, has been used to measure in vivo P-gp activity at various tissue-blood barriers of humans and animals. Since verapamil is extensively metabolized in vivo, it is important to quantify the extent of verapamil metabolism in order to interpret such P-gp activity. Therefore, we developed a rapid solid-phase extraction (SPE) method to separate, and then quantify, verapamil and its radiolabeled metabolites in plasma. Methods: Using high-performance liquid chromatography (HPLC), we established that the major identifiable circulating radioactive metabolite of [ 11 C]-verapamil in plasma of humans and the nonhuman primate, Macaca nemestrina, was [ 11 C]-D-617/717. Using sequential and differential pH elution on C 8 SPE cartridges, we developed a rapid method to separate [ 11 C]-verapamil and [ 11 C]-D-617/717. Recovery was measured by spiking the samples with the corresponding nonradioactive compounds and assaying these compounds by HPLC. Results: Verapamil and D-617/717 recovery with the SPE method was >85%. When the method was applied to PET studies in humans and nonhuman primates, significant plasma concentration of D-617/717 and unknown polar metabolite(s) were observed. The SPE and the HPLC methods were not significantly different in the quantification of verapamil and D-617/717. Conclusions: The SPE method simultaneously processes multiple samples in less than 5 min. Given the short half-life of [ 11 C], this method provides a valuable tool to rapidly determine the concentration of [ 11 C]-verapamil and its [ 11 C]-metabolites in human and nonhuman primate plasma

  16. [18F]Fallypride: Metabolism studies and quantification of the radiotracer and its radiometabolites in plasma using a simple and rapid solid-phase extraction method

    International Nuclear Information System (INIS)

    Peyronneau, Marie-Anne; Saba, Wadad; Goutal, Sébastien; Kuhnast, Bertrand; Dollé, Frédéric; Bottlaender, Michel; Valette, Héric

    2013-01-01

    Introduction: [ 18 F]Fallypride, a fluorinated and substituted benzamide with high affinity for D 2 /D 3 receptors, is a useful PET radioligand for the study of striatal/extrastriatal areas. Since [ 18 F]fallypride is extensively metabolized in vivo and since PET examinations are long lasting in humans, the rapid measurement of the unchanged radiotracer in plasma is essential for the quantification of images. The present study aims: i) to evaluate if the radiometabolites of [ 18 F]fallypride cross the blood–brain barrier in rodents, ii) to identify these radiometabolites in baboon plasma and iii) to develop a rapid solid phase extraction method (SPE) suitable for human applications to quantify both [ 18 F]fallypride and its radiometabolites in plasma. Methods: The metabolites P450-dependant in rat and human liver microsomes were characterized by LC–MS–MS and compared to those detected in vivo. Sequential solvent elution on Oasis®-MCX-SPE cartridges was used to quantify [ 18 F]fallypride and its radiometabolites. Result: In rat microsomal incubations, five metabolites generated upon N/O-dealkylation or hydroxylation at the pyrrolidine and/or at the benzamide moiety were identified. No radiometabolite was detected in the rat brain. N-dealkylated and hydroxylated derivatives were detected in human microsomal incubations as well as in baboon plasma. The use of SPE (total recovery 100.2% ± 2.8%, extraction yield 95.5% ± 0.3%) allowed a complete separation of [ 18 F]fallypride from its radiometabolites in plasma and evaluate [ 18 F]fallypride at 150 min pi to be 22% ± 5% of plasma radioactivity. Conclusions: The major in vivo radiometabolites of [ 18 F]fallypride were produced by N-dealkylation and hydroxylation. Allowing the rapid analysis of multiple plasma samples, SPE is a method of choice for the determination of [ 18 F]fallypride until late images required for quantitative PET imaging in humans

  17. Rapid solid-phase extraction method to quantify [{sup 11}C]-verapamil, and its [{sup 11}C]-metabolites, in human and macaque plasma

    Energy Technology Data Exchange (ETDEWEB)

    Unadkat, Jashvant D. [Department of Pharmaceutics, University of Washington, Box 357610, Seattle, WA 98195 (United States)], E-mail: jash@u.washington.edu; Chung, Francisco; Sasongko, Lucy; Whittington, Dale; Eyal, Sara [Department of Pharmaceutics, University of Washington, Box 357610, Seattle, WA 98195 (United States); Mankoff, David [Department of Radiology, University of Washington, Box 356004, Seattle, WA 98195 (United States); Collier, Ann C. [Department of Medicine, University of Washington, Box 359929, Seattle, WA 98195 (United States); Muzi, Mark; Link, Jeanne [Department of Radiology, University of Washington, Box 356004, Seattle, WA 98195 (United States)

    2008-11-15

    Introduction: P-glycoprotein (P-gp), an efflux transporter, is a significant barrier to drug entry into the brain and the fetus. The positron emission tomography (PET) ligand, [{sup 11}C]-verapamil, has been used to measure in vivo P-gp activity at various tissue-blood barriers of humans and animals. Since verapamil is extensively metabolized in vivo, it is important to quantify the extent of verapamil metabolism in order to interpret such P-gp activity. Therefore, we developed a rapid solid-phase extraction (SPE) method to separate, and then quantify, verapamil and its radiolabeled metabolites in plasma. Methods: Using high-performance liquid chromatography (HPLC), we established that the major identifiable circulating radioactive metabolite of [{sup 11}C]-verapamil in plasma of humans and the nonhuman primate, Macaca nemestrina, was [{sup 11}C]-D-617/717. Using sequential and differential pH elution on C{sub 8} SPE cartridges, we developed a rapid method to separate [{sup 11}C]-verapamil and [{sup 11}C]-D-617/717. Recovery was measured by spiking the samples with the corresponding nonradioactive compounds and assaying these compounds by HPLC. Results: Verapamil and D-617/717 recovery with the SPE method was >85%. When the method was applied to PET studies in humans and nonhuman primates, significant plasma concentration of D-617/717 and unknown polar metabolite(s) were observed. The SPE and the HPLC methods were not significantly different in the quantification of verapamil and D-617/717. Conclusions: The SPE method simultaneously processes multiple samples in less than 5 min. Given the short half-life of [{sup 11}C], this method provides a valuable tool to rapidly determine the concentration of [{sup 11}C]-verapamil and its [{sup 11}C]-metabolites in human and nonhuman primate plasma.

  18. Rapid and Simple Detection of Hot Spot Point Mutations of Epidermal Growth Factor Receptor, BRAF, and NRAS in Cancers Using the Loop-Hybrid Mobility Shift Assay

    Science.gov (United States)

    Matsukuma, Shoichi; Yoshihara, Mitsuyo; Kasai, Fumio; Kato, Akinori; Yoshida, Akira; Akaike, Makoto; Kobayashi, Osamu; Nakayama, Haruhiko; Sakuma, Yuji; Yoshida, Tsutomu; Kameda, Yoichi; Tsuchiya, Eiju; Miyagi, Yohei

    2006-01-01

    A simple and rapid method to detect the epidermal growth factor receptor hot spot mutation L858R in lung adenocarcinoma was developed based on principles similar to the universal heteroduplex generator technology. A single-stranded oligonucleotide with an internal deletion was used to generate heteroduplexes (loop-hybrids) bearing a loop in the complementary strand derived from the polymerase chain reaction product of the normal or mutant allele. By placing deletion in the oligonucleotide adjacent to the mutational site, difference in electrophoretic mobility between loop-hybrids with normal and mutated DNA was distinguishable in a native polyacrylamide gel. The method was also modified to detect in-frame deletion mutations of epidermal growth factor receptor in lung adenocarcinomas. In addition, the method was adapted to detect hot spot mutations in the B-type Raf kinase (BRAF) at V600 and in a Ras-oncogene (NRAS) at Q61, the mutations commonly found in thyroid carcinomas. Our mutation detection system, designated the loop-hybrid mobility shift assay was sensitive enough to detect mutant DNA comprising 7.5% of the total DNA. As a simple and straightforward mutation detection technique, loop-hybrid mobility shift assay may be useful for the molecular diagnosis of certain types of clinical cancers. Other applications are also discussed. PMID:16931592

  19. Epitaxial growth and new phase of single crystal Dy by molecular beam epitaxy

    International Nuclear Information System (INIS)

    Yang, Kai-Yueh; Homma, Hitoshi; Schuller, I.K.

    1987-09-01

    We have grown two novel epitaxial phases of dysprosium (Dy) on vanadium (V) by molecular beam epitaxy technique. Surface and bulk structures are studied by in-situ reflection high energy electron diffraction (RHEED) and x-ray diffraction techniques. The new hcp phases are ∼4% expanded uniformly in-plane (0001), and ∼9% and ∼4% expanded out of plane along the c-axes for non-interrupted and interrupted deposition case, respectively. We also observed (2 x 2), (3 x 3), and (4 x 4) Dy surface reconstruction patterns and a series of transitions as the Dy film thickness increases. 12 refs., 3 figs

  20. Slow growth of the Rayleigh-Plateau instability in aqueous two phase systems

    NARCIS (Netherlands)

    Geschiere, S.D.; Ziemecka, I.; Van Steijn, V.; Koper, G.J.M.; Van Esch, J.H.; Kreutzer, M.T.

    2012-01-01

    This paper studies the Rayleigh-Plateau instability for co-flowing immiscible aqueous polymer solutions in a microfluidic channel. Careful vibration-free experiments with controlled actuation of the flow allowed direct measurement of the growth rate of this instability. Experiments for the

  1. Radiation-induced p53 protein response in the A549 cell line is culture growth-phase dependent

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, N.F.; Gurule, D.M.; Carpenter, T.R.

    1995-12-01

    One role of the p53 tumor suppressor protein has been recently revealed. Kastan, M.B. reported that p53 protein accumulates in cells exposed to ionizing radiation. The accumulation of p53 protein is in response to DNA damage, most importantly double-strand breaks, that results from exposure to ionizing radiation. The rise in cellular p53 levels is necessary for an arrest in the G{sub 1} phase of the cell cycle to provide additional time for DNA repair. The p53 response has also been demonstrated to enhance PCNA-dependent repair. p53 is thus an important regulator of the cellular response to DNA-damaging radiation. From this data, it can be concluded that the magnitude of the p53 response is not dependent on the phase of culture growth.

  2. Fabrication of a Schottky junction diode with direct growth graphene on silicon by a solid phase reaction

    International Nuclear Information System (INIS)

    Kalita, Golap; Hirano, Ryo; Ayhan, Muhammed E; Tanemura, Masaki

    2013-01-01

    We demonstrate fabrication of a Schottky junction diode with direct growth graphene on n-Si by the solid phase reaction approach. Metal-assisted crystallization of a-C thin film was performed to synthesize transfer-free graphene directly on a SiO 2 patterned n-Si substrate. Graphene formation at the substrate and catalyst layer interface is achieved in presence of a Co catalytic and CoO carbon diffusion barrier layer. The as-synthesized material shows a linear current–voltage characteristic confirming the metallic behaviour of the graphene structure. The direct grown graphene on n-Si substrate creates a Schottky junction with a potential barrier of 0.44 eV and rectification diode characteristic. Our finding shows that the directly synthesized graphene on Si substrate by a solid phase reaction process can be a promising technique to fabricate an efficient Schottky junction device. (paper)

  3. Microalgae growth on the aqueous phase from Hydrothermal Liquefaction of the same microalgae

    NARCIS (Netherlands)

    Garcia Alba, Laura; Torri, Cristian; Fabbri, Daniele; Kersten, Sascha R.A.; Brilman, Derk Willem Frederik

    2013-01-01

    Cultivation of Desmodesmus sp. microalgae in the recycled aqueous phase (AP) recovered after Hydrothermal Liquefaction (HTL) of the same microalgae was studied to evaluate the potential of nutrients recycling. AP dilution ratio was systematically varied, using either water or water enriched with

  4. Physiological-phased kinetic characteristics of microalgae Chlorella vulgaris growth and lipid synthesis considering synergistic effects of light, carbon and nutrients.

    Science.gov (United States)

    Liao, Qiang; Chang, Hai-Xing; Fu, Qian; Huang, Yun; Xia, Ao; Zhu, Xun; Zhong, Nianbing

    2018-02-01

    To comprehensively understand kinetic characteristics of microalgae growth and lipid synthesis in different phases, a phase-feeding strategy was proposed to simultaneously regulate light, carbon and nutrients in adaption, growth and stationary phases of microalgae cultivation. Physiological-phased kinetic characteristics of microalgae Chlorella vulgaris growth and lipid synthesis under synergistic effects of light, carbon and nutrients were investigated, and supply-demand relationships of electrons and energy between light and dark reactions of photosynthesis process were discussed. Finally, the optimized cultivation strategy for microalgae in various phases were obtained, under which the lipid productivity was significantly improved from 130.11 mg/L/d to 163.42 mg/L/d. The study provided some important guidance for the large-scale production of biofuels from microalgae. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Optimization of matrix solid-phase dispersion for the rapid determination of salicylate and benzophenone-type UV absorbing substances in marketed fish.

    Science.gov (United States)

    Tsai, Dung-Ying; Chen, Chien-Liang; Ding, Wang-Hsien

    2014-07-01

    A simple and effective method for the rapid determination of five salicylate and benzophenone-type UV absorbing substances in marketed fish is described. The method involves the use of matrix solid-phase dispersion (MSPD) prior to their determination by on-line silylation gas chromatography tandem mass spectrometry (GC-MS/MS). The parameters that affect the extraction efficiency were optimized using a Box-Behnken design method. The optimal extraction conditions involved dispersing 0.5g of freeze-dried powdered fish with 1.0g of Florisil using a mortar and pestle. This blend was then transferred to a solid-phase extraction (SPE) cartridge containing 1.0g of octadecyl bonded silica (C18), as the clean-up co-sorbent. The target analytes were then eluted with 7mL of acetonitrile. The extract was derivatized on-line in the GC injection-port by reaction with a trimethylsilylating (TMS) reagent. The TMS-derivatives were then identified and quantitated by GC-MS/MS. The limits of quantitation (LOQs) were less than 0.1ng/g. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Rapid ultrasound-induced transient-liquid-phase bonding of Al-50Si alloys with Zn interlayer in air for electrical packaging application.

    Science.gov (United States)

    Wang, Qian; Chen, Xiaoguang; Zhu, Lin; Yan, Jiuchun; Lai, Zhiwei; Zhao, Pizhi; Bao, Juncheng; Lv, Guicai; You, Chen; Zhou, Xiaoyu; Zhang, Jian; Li, Yuntao

    2017-01-01

    Al-50Si alloys were joined by rapid ultrasound-induced transient-liquid-phase bonding method using Zn foil as interlayer at 390°C in air, below the melt point of interlayer. The fracture of oxide films along the edge of Si particles led to contact and inter-diffusion between aluminum substrate and Zn interlayer, and liquefied Zn-Al alloys were developed. The width of Zn-Al alloys gradually decreased with increasing the ultrasonic vibration time due to liquid squeezing out and accelerated diffusion. A stage of isothermal solidification existed, and the completion time was significantly shortened. In the liquid metal, the acoustic streaming and ultrasonic cavitations were induced. As the process developed, much more Si particles, which were particulate-reinforced phases of Al-50Si, gradually migrated to the center of soldering seam. The highest average shear strength of joints reached to 94.2MPa, and the fracture mainly occurred at the base metal. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Numerical analysis of interfacial growth and deformation in horizontal stratified two-phase flow by lattice Boltzmann method

    International Nuclear Information System (INIS)

    Ebihara, Ken-ichi

    2005-03-01

    paper, first, the validity and the usefulness of the lattice-gas model and the lattice Boltzmann method for the numerical analysis of two-phase flow are examined by applying the two-phase fluid model of these methods to the phenomena of the falling droplet and the rising bubble. Next, on the basis of the examination of its numerical results, the horizontal stratified two-phase flow, which is the fundamental and important flow and often observed in a practical situation, is simulated by use of the HCZ model that is the two-phase fluid model of the lattice Boltzmann method proposed by He, Chen, and Zhang. The HCZ model can simulate Rayleigh-Taylor instability which shows complex interfacial phenomena. It is verified that the simulated interfacial growth is subject to the Kelvin-Helmholtz instability theory and can reproduce the curve concerning the interfacial growth of the theoretical flow regime map proposed by Taitel and Dukler (T-D map). Furthermore, it is found that the interfacial growth in the channel with the narrow width needs more superficial flow velocity than that given by the T-D map. In the simulation of the droplet generation in the horizontal stratified two-phase flow, it is verified that the HCZ model can also reproduce the experimental correlation proposed by Ishii and Grolmes within the range of the distribution of experimental data. According to the results of this report, it is found that the HCZ model of the lattice Boltzmann method can simulate complex interfacial phenomena in the horizontal stratified two-phase flow and reproduce the theoretical flow regime map and the experimental correlation. Considering the application of this model to more practical two-phase flow, it is also seen that this model has some problems which have to be solved, such as practical density difference, thermal influence and so on. (author)

  8. Control of nucleation and crystal growth of a silicate apatitic phase in a glassy matrix

    International Nuclear Information System (INIS)

    Ligny, D.; Caurant, D.; Bardez, I.; Dussossoy, J.L.; Loiseau, P.; Neuville, D.R.

    2004-01-01

    Nucleation and growth of crystal in an oxide glass was studied in a Si B Al Zr Nd Ca Na O system. The nucleation and growth process were monitored by thermal analysis and isothermal experiments. The effect of the network modifier was studied. Therefore for a Ca rich sample the crystallization is homogeneous in the bulk showing a slow increase of crystallinity as temperature increases. On the other hand, a Na rich sample undergoes several crystallization processes in the bulk or from the surface, leading to bigger crystals. The activation energy of the viscous flow and the glass transition are of same magnitude when that of crystallization is a lot smaller. Early diffusion of element is done with a mechanism different than the configurational rearrangements of the liquid sate. The global density and small size of the crystals within the Ca rich matrix confirmed that it would be a profitable waste form for minor actinides. (authors)

  9. Growth kinetics of the intermetallic phase in diffusion-soldered (Cu-5 at.%Ni)/Sn/(Cu-5 at.%Ni) interconnections

    NARCIS (Netherlands)

    Wierzbicka-Miernik, A.; Miernik, K.; Wojewoda-Budka, J.; Szyszkiewicz, K.; Filipek, R.; Litynska-Dobrzynska, L.; Kodentsov, A.; Zieba, P.

    2013-01-01

    A stereological analysis was carried out in order to obtain the kinetics parameters of the (Cu1-xNix)6Sn5 growth in the diffusion soldered (Cu–5 at.%Ni)/Sn/(Cu–5 at.%Ni) interconnections where previously anomalous fast growth of this phase was described. The n-parameter in the equation x = ktn was

  10. Order-disorder criticality, wetting, and morphological phase transitions in the irreversible growth of far-from-equilibrium magnetic films

    International Nuclear Information System (INIS)

    Candia, J.Julian; Albano, E.V.Ezequiel V.

    2003-01-01

    An exhaustive numerical investigation of the growth of magnetic films in confined (d+1)-dimensional stripped geometries (d=1,2) is carried out by means of extensive Monte Carlo simulations. Films in contact with a thermal bath at temperature T, are grown by adding spins having two possible orientations and considering ferromagnetic (nearest-neighbor) interactions. At low temperatures, thin films of thickness L are constituted by a sequence of well-ordered domains of average length l D >>L. These domains have opposite magnetization. So, the films exhibit 'spontaneous magnetization reversal' during the growth process. Such reversal occurs within a short characteristic length l R , such that l D >>l R ∼L. Furthermore, it is found that for d=1 the system is non-critical, while a continuous order-disorder phase transition at finite temperature takes place in the d=2 case. Using standard finite-size scaling procedures, the critical temperature and some relevant critical exponents are determined. Finally, the growth of magnetic films in (2+1) dimensions with competing short-range magnetic fields acting along the confinement walls is studied. Due to the antisymmetric condition considered, an interface between domains with spins having opposite orientation develops along the growing direction. Such an interface undergoes a localization-delocalization transition that is the precursor of a wetting transition in the thermodynamic limit. Furthermore, the growing interface also undergoes morphological transitions in the growth mode. A comparison between the well-studied equilibrium Ising model and the studied irreversible magnetic growth model is performed throughout. Although valuable analogies are encountered, it is found that the non-equilibrium nature of the latter introduces new and rich physical features of interest

  11. Rapid Quantitative Analysis of Naringenin in the Fruit Bodies of Inonotus vaninii by Two-phase Acid Hydrolysis Followed by Reversed Phase-high Performance Liquid Chromatography-ultra Violet.

    Science.gov (United States)

    Guohua, Xia; Pan, Ruirong; Bao, Rui; Ge, Yanru; Zhou, Cunshan; Shen, Yuping

    2017-01-01

    Sanghuang is one of mystical traditional Chinese medicines recorded earliest 2000 years ago, that included various fungi of Inonotus genus and was well-known for antitumor effect in modern medicine. Inonotus vaninii is grown in natural forest of Northeastern China merely and used as Sanghuang commercially, but it has no quality control specification until now. This study was to establish a rapid method of two-phase acid hydrolysis followed by reversed phase-high performance liquid chromatography-ultra violet (RP-HPLC-UV) to quantify naringenin in the fruit body of I. vaninii . Sample solution was prepared by pretreatment of raw material in two-phase acid hydrolysis and the hydrolysis technology was optimized. After reconstitution, analysis was performed using RP-HPLC-UV. The method validation was investigated and the naringenin content of sample and comparison were determined. The naringenin was obtained by two-phase acid hydrolysis method, namely, 10.0 g of raw material was hydrolyzed in 200 mL of 1% sulfuric acid aqueous solution (v/v) and 400 mL of chloroform in oil bath at 110°C for 2 h. Good linearity ( r = 0.9992) was achieved between concentration of analyte and peak area. The relative standard deviation (RSD) of precision was 2.47% and the RSD of naringenin contents for repeatability was 3.13%. The accuracy was supported with recoveries at 96.37%, 97.30%, and 99.31%. The sample solution prepared using the proposed method contained higher content of naringenin than conventional method and was stable for 8 h. Due to the high efficiency of sample preparation and high reliability of the HPLC method, it is feasible to use this method for routine analysis of naringenin in the fungus. A convenient two-phase acid hydrolysis was employed to produce naringenin from raw material, and then an efficient and reliable reversed phase-high performance liquid chromatography-ultra violet method was established to monitor naringenin in the fruit bodies of Inonotus vaninii

  12. Chlamydomonas reinhardtii: duration of its cell cycle and phases at growth rates affected by light intensity

    Czech Academy of Sciences Publication Activity Database

    Vítová, Milada; Bišová, Kateřina; Umysová, Dáša; Hlavová, Monika; Kawano, S.; Zachleder, Vilém; Čížková, Mária

    2011-01-01

    Roč. 233, č. 1 (2011), s. 75-86 ISSN 0032-0935 R&D Projects: GA AV ČR IAA500200614; GA ČR GA525/09/0102; GA ČR GA204/09/0111 Institutional research plan: CEZ:AV0Z50200510 Keywords : Cell division timing * Cell cycle phases * Chlamydomonas Subject RIV: EE - Microbiology, Virology Impact factor: 3.000, year: 2011

  13. Crystal growth and electronic structure of low-temperature phase SrMgF{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Atuchin, Victor V. [Laboratory of Optical Materials and Structures, Institute of Semiconductor Physics, SB RAS, Novosibirsk 630090 (Russian Federation); Functional Electronics Laboratory, Tomsk State University, Tomsk 634050 (Russian Federation); Laboratory of Semiconductor and Dielectric Materials, Novosibirsk State University, Novosibirsk 630090 (Russian Federation); Goloshumova, Alina A. [Laboratory of Crystal Growth, Institute of Geology and Mineralogy, SB RAS, Novosibirsk 630090 (Russian Federation); Isaenko, Ludmila I. [Laboratory of Semiconductor and Dielectric Materials, Novosibirsk State University, Novosibirsk 630090 (Russian Federation); Laboratory of Crystal Growth, Institute of Geology and Mineralogy, SB RAS, Novosibirsk 630090 (Russian Federation); Jiang, Xingxing [BCCRD, Key Laboratory of Functional Crystals and Laser Technology, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Lobanov, Sergey I. [Laboratory of Crystal Growth, Institute of Geology and Mineralogy, SB RAS, Novosibirsk 630090 (Russian Federation); Zhang, Zhaoming [Australian Nuclear Science & Technology Organisation, Lucas Heights, NSW 2234 (Australia); Lin, Zheshuai, E-mail: zslin@mail.ipc.ac.cn [BCCRD, Key Laboratory of Functional Crystals and Laser Technology, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China)

    2016-04-15

    Using the vertical Bridgman method, the single crystal of low temperature phase SrMgF{sub 4} is obtained. The crystal is in a very good optical quality with the size of 10×7×5 mm{sup 3}. Detailed photoemission spectra of the element core levels are determined by a monochromatic AlKa (1486.6 eV) X-ray source. Moreover, the first-principles calculations are performed to investigate the electronic structure of SrMgF{sub 4}. A good agreement between experimental and calculated results is achieved. It is demonstrated that almost all the electronic orbitals are strongly localized and the hybridization with the others is very small, but the Mg–F bonds covalency is relatively stronger than that of Sr–F bonds. - Graphical abstract: Large size of low-temperature phase SrMgF{sub 4} crystal was obtained (right) and its electronic structure was investigated by X-ray photoelectron spectroscopy and first-principles calculation (left). - Highlights: • Large size single crystal of low-temperature phase SrMgF{sub 4} is obtained. • Electronic structure of SrMgF{sub 4} is measured by X-ray photoelectron spectroscopy. • Partial densities of states are determined by first-principles calculation. • Good agreement between experimental and calculated results is achieved. • Strong ionic characteristics of chemical bonds are exhibited in SrMgF{sub 4}.

  14. Unusual Growth Phase and Oxygen Tension Regulation of Oxidative Stress Protection Enzymes, Catalase and Superoxide Dismutase, in the Phytopathogen Xanthomonas oryzae pv. oryzae

    OpenAIRE

    Chamnongpol, S.; Mongkolsuk, S.; Vattanaviboon, P.; Fuangthong, M.

    1995-01-01

    The enzymes catalase and superoxide dismutase play major roles in protecting phytopathogenic bacteria from oxidative stress. In Xanthomonas species, these enzymes are regulated by both growth phase and oxygen tension. The highest enzyme levels were detected within 1 h of growth. Continued growth resulted in a decline of both enzyme activities. High oxygen tension was an inducing signal for both enzyme activities. An 80,000-Da monofunctional catalase and a manganese superoxide dismutase were t...

  15. The quiet evening auroral arc and the structure of the growth phase near-Earth plasma sheet

    Science.gov (United States)

    Coroniti, F. V.; Pritchett, P. L.

    2014-03-01

    The plasma pressure and current configuration of the near-Earth plasma sheet that creates and sustains the quiet evening auroral arc during the growth phase of magnetospheric substorms is investigated. We propose that the quiet evening arc (QEA) connects to the thin near-Earth current sheet, which forms during the development of the growth phase enhancement of convection. The current sheet's large polarization electric fields are shielded from the ionosphere by an Inverted-V parallel potential drop, thereby producing the electron precipitation responsible for the arc's luminosity. The QEA is located in the plasma sheet region of maximal radial pressure gradient and, in the east-west direction, follows the vanishing of the approximately dawn-dusk-directed gradient or fold in the plasma pressure. In the evening sector, the boundary between the Region1 and Region 2 current systems occurs where the pressure maximizes (approximately radial gradient of the pressure vanishes) and where the approximately radial gradient of the magnetic flux tube volume also vanishes in an inflection region. The proposed intricate balance of plasma sheet pressure and currents may well be very sensitive to disruption by the arrival of equatorward traveling auroral streamers and their associated earthward traveling dipolarization fronts.

  16. Examination and modeling of void growth kinetics in modern high strength dual phase steels during uniaxial tensile deformation

    Energy Technology Data Exchange (ETDEWEB)

    Saeidi, N., E-mail: navidsae@gmail.com [Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Ashrafizadeh, F.; Niroumand, B. [Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Forouzan, M.R.; Mohseni mofidi, S. [Department of Mechanical Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Barlat, F. [Materials Mechanics Laboratory (MML), Graduate Institute of Ferrous Technology (GIFT), Pohang University of Science and Technology - POSTECH, San 31 Hyoja-dong, Nam-gu, Pohang, Gyeongbuk 790-784 (Korea, Republic of)

    2016-04-01

    Ductile fracture mechanisms during uniaxial tensile testing of two different modern high strength dual phase steels, i.e. DP780 and DP980, were studied. Detailed microstructural characterization of the strained and sectioned samples was performed by scanning electron microscopy as well as EBSD examination. The results revealed that interface decohesion, especially at martensite particles located at ferrite grain boundaries, was the most probable mechanism for void nucleation. It was also revealed that the creation of cellular substructure can reduce stored strain energy and thereby, higher true fracture strain was obtained in DP980 than DP780 steel. Prediction of void growth behavior based on some previously proposed models showed unreliable results. Therefore, a modified model based on Rice-Tracey family models was proposed which showed a very lower prediction error compared with other models. - Highlights: • Damage mechanism in two modern high strength dual phase steels was studied. • Creation of cellular substructures can reduce the stored strain energy within the ferrite grains. • The experimental values were examined by Agrawal as well as RT family models. • A modified model was proposed for prediction of void growth behavior of DP steels.

  17. Wide-range high-resolution transmission electron microscopy reveals morphological and distributional changes of endomembrane compartments during log to stationary transition of growth phase in tobacco BY-2 cells.

    Science.gov (United States)

    Toyooka, Kiminori; Sato, Mayuko; Kutsuna, Natsumaro; Higaki, Takumi; Sawaki, Fumie; Wakazaki, Mayumi; Goto, Yumi; Hasezawa, Seiichiro; Nagata, Noriko; Matsuoka, Ken

    2014-09-01

    Rapid growth of plant cells by cell division and expansion requires an endomembrane trafficking system. The endomembrane compartments, such as the Golgi stacks, endosome and vesicles, are important in the synthesis and trafficking of cell wall materials during cell elongation. However, changes in the morphology, distribution and number of these compartments during the different stages of cell proliferation and differentiation have not yet been clarified. In this study, we examined these changes at the ultrastructural level in tobacco Bright yellow 2 (BY-2) cells during the log and stationary phases of growth. We analyzed images of the BY-2 cells prepared by the high-pressure freezing/freeze substitution technique with the aid of an auto-acquisition transmission electron microscope system. We quantified the distribution of secretory and endosomal compartments in longitudinal sections of whole cells by using wide-range gigapixel-class images obtained by merging thousands of transmission electron micrographs. During the log phase, all Golgi stacks were composed of several thick cisternae. Approximately 20 vesicle clusters (VCs), including the trans-Golgi network and secretory vesicle cluster, were observed throughout the cell. In the stationary-phase cells, Golgi stacks were thin with small cisternae, and only a few VCs were observed. Nearly the same number of multivesicular body and small high-density vesicles were observed in both the stationary and log phases. Results from electron microscopy and live fluorescence imaging indicate that the morphology and distribution of secretory-related compartments dramatically change when cells transition from log to stationary phases of growth. © The Author 2014. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  18. Light contamination during the dark phase in "photoperiodically controlled" animal rooms: effect on tumor growth and metabolism in rats.

    Science.gov (United States)

    Dauchy, R T; Sauer, L A; Blask, D E; Vaughan, G M

    1997-10-01

    Enhanced neoplastic growth and metabolism have been reported in animals maintained in a constant light (24L:0D) environment. Results from this laboratory indicate that tumor growth is directly dependent upon increased ambient blood concentrations of arachidonic and linoleic acids, particularly linoleic acid. Tumor linoleic acid utilization and production if its putative mitogenic metabolite, 13-hydroxyoctadecadienoic acid (13-HODE), are suppressed by the circadian neurohormone melatonin, the production of which is itself regulated by light in all mammals. This study was performed to determine whether minimal light contamination (0.2 lux) in an animal room during an otherwise normal dark phase may disrupt normal circadian production of melatonin and affect tumor growth and metabolism. Animals of groups I (12L:12D), II (12L:12-h light-contaminated dark phase), and III (24L:0D) had plasma total fatty acid (TFA), linoleic acid (LA), and melatonin concentrations measured prior to tumor implantation; groups I and II had daily cycles in plasma TFA and LA values, whereas group III had constant values throughout the day. The integrated mean TFA and LA values for the entire day were similar in all groups. Although group-I animals had a normal nocturnal surge of melatonin (127.0 pg/ml) at 2400 h, the nocturnal amplitude was suppressed in group-II animals (16.0 pg/ml); circadian variation in melatonin concentration was not seen in group-III animals (7.4 pg/ml). At 12 weeks of age, rats had the Morris hepatoma 7288CTC implanted as "tissue-isolated" tumors grown subcutaneously. Latency to onset of palpable tumor mass for groups I, II, and III was 11, 9, and 5 days respectively. Tumor growth rates were 0.72 +/- 0.09, 1.30 +/- 0.15, and 1.48 +/- 0.17 g/d (mean +/- SD, n = 6/group) in groups I, II, and III respectively. Arteriovenous difference measurements for TFA and LA across the tumors were 4.22 +/- 0.89 and 0.83 +/- 0.18 (group I), 8.26 +/- 0.66 and 1.64 +/- 0.13 (group II

  19. Growth phase dependent hydrogen isotopic fractionation in alkenone-producing haptophytes

    Directory of Open Access Journals (Sweden)

    M. D. Wolhowe

    2009-08-01

    Full Text Available Recent works have investigated use of the hydrogen isotopic composition of C37 alkenones (δDK37s, lipid biomarkers of certain haptophyte microalgae, as an independent paleosalinity proxy. We discuss herein the factors impeding the success of such an application and identify the potential alternative use of δDK37s measurements as a proxy for non-thermal, physiological stress impacts on the U37K' paleotemperature index. Batch-culture experiments with the haptophyte Emiliania huxleyi (CCMP 1742 were conducted to determine the magnitude and variability of the isotopic contrasts between individual C37 alkenones. Further experiments were conducted with Emiliania huxleyi (CCMP 1742 andGephyrocapsa oceanica (PZ3-1 to determine whether, and to what extent, δDK37s varies between the physiological extremes of nutrient-replete exponential growth and nutrient-depleted senescence. Emiliania huxleyi was observed to exhibit an isotopic contrast between di- and tri-unsaturated C37 alkenones (αK37:3-K37:2≈0.97 that is nearly identical to that reported recently by others for environmental samples. Furthermore, this contrast appears to be constant with growth stage. The consistency of the offset across different growth stages suggests that a single, well-defined value for αK37:3-K37:2 may exist and that its use in an isotope mass-balance will allow accurate determination of δD values for individual alkenones without having to rely on time- and labor-intensive chemical separations. The isotopic fractionation between growth medium and C37 alkenones was observed to increase dramatically upon the onset of nutrient-depletion-induced senescence, suggesting that δDK37s may serve as an objective tool for recognizing and potentially correcting, at least semi-quantitatively, for the effects

  20. Spatial divergence of living standards during the economic growth phase in the periphery: A case study of North Karelia

    Directory of Open Access Journals (Sweden)

    Olli Lehtonen

    2011-01-01

    Full Text Available The advisability of an urban-centred growth strategy in sparsely populated parts of Europe has not been much analysed at micro-levels such as that of the postcode area. This paper investigates how regional disparities in living standards continued to increase during the technology-driven growth phase of 1993−2003, as exemplified by the case of North Karelia in Finland. Urban sprawl conveyed the spread effects of the rise in incomes, and the upsurge of living standards was concentrated in the neighbourhood of the provincial centre, Joensuu. Living standards faced a process of double divergence: between the central district of Joensuu and its commuter belt, and between the provincial core area and its hinterland, the latter consisting of rural areas and small towns dependent largely on natural resources. The spatial outcome of this socio-economic reorganization is a three-zone core-periphery pattern. As the economy grew, geographical shifts in wealth were consequences of the growth and mobility of certain social groups and strata. A wave of high living standards towards the outskirts of the provincial centre was generated by an expansion in commuting. The relative decline in living standards in the periphery was due to long-term rural decline and involved spatial restructuring.

  1. A rapid hydrolysis method and DABS-Cl derivatization for complete amino acid analysis of octreotide acetate by reversed phase HPLC.

    Science.gov (United States)

    Akhlaghi, Yousef; Ghaffari, Solmaz; Attar, Hossein; Alamir Hoor, Amir

    2015-11-01

    Octreotide as a synthetic cyclic octapeptide is a somatostatin analog with longer half-life and more selectivity for inhibition of the growth hormone. The acetate salt of octreotide is currently used for medical treatment of somatostatin-related disorders such as endocrine and carcinoid tumors, acromegaly, and gigantism. Octreotide contains both cysteine and tryptophan residues which make the hydrolysis part of its amino acid analysis procedure very challenging. The current paper introduces a fast and additive-free method which preserves tryptophan and cysteine residues during the hydrolysis. Using only 6 M HCl, this hydrolysis process is completed in 30 min at 150 °C. This fast hydrolysis method followed by pre-column derivatization of the released amino acids with 4-N,N-dimethylaminoazobenzene-4'-sulfonyl chloride (DABS-Cl) which takes only 20 min, makes it possible to do the complete amino acid analysis of an octreotide sample in a few hours. The highly stable-colored DABS-Cl derivatives can be detected in 436 nm in a reversed phase chromatographic system, which eliminates spectral interferences to a great extent. The amino acid analysis of octreotide acetate including hydrolysis, derivatization, and reversed phase HPLC determination was validated according to International Conference of Harmonization (ICH) guidelines.

  2. Effect of Thermal Annealing and Second Harmonic Generation on Bulk Damage Performance of Rapid-Growth KDP Type I Doublers at 1064 nm

    International Nuclear Information System (INIS)

    Runkel, M; Maricle, S; Torres, R; Auerbach, J; Floyd, R; Hawley-Fedder, R; Burnham, A K

    2000-01-01

    This paper discusses the results of thermal annealing and in-situ second harmonic generation (SHG) damage tests performed on six rapid growth KDP type 1 doubler crystals at 1064 nm (1 ω) on the Zeus automated damage test facility. Unconditioned (S/1) and conditioned (R/1) damage probability tests were performed before and after thermal annealing, then with and without SHG on six doubler crystals from the NIF-size, rapid growth KDP boule F6. The tests revealed that unannealed, last-grown material from the boule in either prismatic or pyramidal sectors exhibited the highest damage curves. After thermal annealing at 160 C for seven days, the prismatic sector samples increased in performance ranging from 1.6 to 2.4X, while material from the pyramidal sector increased only modestly, ranging from 1.0 to 1.4X. Second harmonic generation decreased the damage fluence by an average of 20 percent for the S/1 tests and 40 percent for R/1 tests. Conversion efficiencies under test conditions were measured to be 20 to 30 percent and compared quite well to predicted behavior, as modeled by LLNL frequency conversion computer codes. The damage probabilities at the 1 ω NIF redline fluence (scaled to 10 ns via t 0.5 ) for S/1 tests for the unannealed samples ranged from 20 percent in one sample to 90-100 percent for the other 5 samples. Thermal annealing reduced the damage probabilities to less than 35 percent for 3 of the poor-performing crystals, while two pyramidal samples remained in the 80 to 90 percent range. Second harmonic generation in the annealed crystal increased the S/1 damage probabilities on all the crystals and ranged from 40 to 100 percent. In contrast, R/1 testing of an unannealed crystal resulted in a damage probability at the NIF redline fluence of 16%. Annealing increased the damage performance to the extent that all test sites survived NIF redline fluences without damage. Second harmonic generation in the R/1 test yielded a damage probability of less than 2

  3. Growth of potassium niobate micro-hexagonal tablets with monoclinic phase and its excellent piezoelectric property

    Science.gov (United States)

    Chen, Zhong; Huang, Jingyun; Wang, Ye; Yang, Yefeng; Wu, Yongjun; Ye, Zhizhen

    2012-09-01

    Potassium niobate micro-hexagonal tablets were synthesized through hydrothermal reaction with KOH, H2O and Nb2O5 as source materials by using a polycrystalline Al2O3 as substrate. X-ray diffraction, Raman spectra and selected area electron diffraction analysis results indicated that the tablets exhibit monoclinic phase structure and are highly crystallized. Meanwhile, piezoelectric property of the micro-hexagonal tablets was investigated. The as-synthesized tablets exhibit excellent piezoactivities in the experiments, and an effective piezoelectric coefficient of around 80 pm/V was obtained. The tablets have huge potential applications in micro/nano-integrated piezoelectric and optical devices.

  4. Forensics of subhalo-stream encounters: the three phases of gap growth

    Science.gov (United States)

    Erkal, Denis; Belokurov, Vasily

    2015-06-01

    There is hope to discover dark matter subhaloes free of stars (predicted by the current theory of structure formation) by observing gaps they produce in tidal streams. In fact, this is the most promising technique for dark substructure detection and characterization as such gaps grow with time, magnifying small perturbations into clear signatures observable by ongoing and planned Galaxy surveys. To facilitate such future inference, we develop a comprehensive framework for studies of the growth of the stream density perturbations. Starting with simple assumptions and restricting to streams on circular orbits, we derive analytic formulae that describe the evolution of all gap properties (size, density contrast, etc.) at all times. We uncover complex, previously unnoticed behaviour, with the stream initially forming a density enhancement near the subhalo impact point. Shortly after, a gap forms due to the relative change in period induced by the subhalo's passage. There is an intermediate regime where the gap grows linearly in time. At late times, the particles in the stream overtake each other, forming caustics, and the gap grows like √{t}. In addition to the secular growth, we find that the gap oscillates as it grows due to epicyclic motion. We compare this analytic model to N-body simulations and find an impressive level of agreement. Importantly, when analysing the observation of a single gap we find a large degeneracy between the subhalo mass, the impact geometry and kinematics, the host potential, and the time since flyby.

  5. Rapid point-of-care testing for epidermal growth factor receptor gene mutations in patients with lung cancer using cell-free DNA from cytology specimen supernatants.

    Science.gov (United States)

    Asaka, Shiho; Yoshizawa, Akihiko; Saito, Kazusa; Kobayashi, Yukihiro; Yamamoto, Hiroshi; Negishi, Tatsuya; Nakata, Rie; Matsuda, Kazuyuki; Yamaguchi, Akemi; Honda, Takayuki

    2018-06-01

    Epidermal growth factor receptor (EGFR) mutations are associated with responses to EGFR tyrosine kinase inhibitors (EGFR-TKIs) in non-small-cell lung cancer (NSCLC). Our previous study revealed a rapid point-of-care system for detecting EGFR mutations. This system analyzes cell pellets from cytology specimens using droplet-polymerase chain reaction (d-PCR), and has a reaction time of 10 min. The present study aimed to validate the performance of the EGFR d-PCR assay using cell-free DNA (cfDNA) from supernatants obtained from cytology specimens. Assay results from cfDNA supernatant analyses were compared with those from cell pellets for 90 patients who were clinically diagnosed with, or suspected of having, lung cancer (80 bronchial lavage fluid samples, nine pleural effusion samples and one spinal fluid sample). EGFR mutations were identified in 12 and 15 cases using cfDNA supernatants and cell pellets, respectively. The concordance rates between cfDNA-supernatant and cell‑pellet assay results were 96.7% [kappa coefficient (K)=0.87], 98.9% (K=0.94), 98.9% (K=0.79) and 98.9% (K=0.79) for total EGFR mutations, L858R, E746_A750del and T790M, respectively. All 15 patients with EGFR mutation-positive results, as determined by EGFR d-PCR assay using cfDNA supernatants or cell pellets, also displayed positive results by conventional EGFR assays using tumor tissue or cytology specimens. Notably, EGFR mutations were even detected in five cfDNA supernatants for which the cytological diagnoses of the corresponding cell pellets were 'suspicious for malignancy', 'atypical' or 'negative for malignancy.' In conclusion, this rapid point-of-care system may be considered a promising novel screening method that may enable patients with NSCLC to receive EGFR-TKI therapy more rapidly, whilst also reserving cell pellets for additional morphological and molecular analyses.

  6. The impact of rapid population growth, expanding urbanisation, and other factors on development in sub-Saharan Africa: the contrasting responses of Tanzania and Kenya.

    Science.gov (United States)

    Huth, M J

    1984-01-01

    This article analyzes the impact of the twin factors of rapid population growth and expanding urbanization on social and economic development in sub-Saharan Africa and compares policies that have been developed in Tanzania and Kenya in response to these factors. The principal consequences of overpopulation and overurbanization have been economic stagnation and physical and cultural malaise in urban population centers. Between 1960-80, per capita incomes in 19 countries of sub-Saharan Africa grew by less than 1%/year and 15 countries recorded a negative rate of growth in per capita income during the 1970s. Urban populations have increased at at overall rate of 6%/year as sub-Saharan Africans have migrated to cities in search of employment. Few national governments in the region have formulated longterm strategies to deal effectively with this double-faceted development constraint or have integrated new urban populations into the national economy. tanzania's development strategy is focused on the goals of socialism, rural development, and self-reliance. Urban development has remained a residual item in Tanzania's national development process, despite the fact that the urban population increased from 5.7% of the total population in 1967 to 12.7% in 1978 and is projected to comprise 24.7% by the year 2000. In contrast, Kenya, whose proportion of urban population increased from 9% to 15% between 1962 and 1979, has pursued an urban-focused development strategy. The strong urban-rural linkages of the economy have focused migration to the secondary towns. The national development plan includes urban spatial, employment, and investment policies. Although this plan constitutes a good basis for future planning, the magnitude of the urban problem is beyond the capabilities of the central government and requires the development of local capabilities.

  7. A FIRE-ACE/SHEBA Case Study of Mixed-Phase Arctic Boundary Layer Clouds: Entrainment Rate Limitations on Rapid Primary Ice Nucleation Processes

    Science.gov (United States)

    Fridlin, Ann; vanDiedenhoven, Bastiaan; Ackerman, Andrew S.; Avramov, Alexander; Mrowiec, Agnieszka; Morrison, Hugh; Zuidema, Paquita; Shupe, Matthew D.

    2012-01-01

    Observations of long-lived mixed-phase Arctic boundary layer clouds on 7 May 1998 during the First International Satellite Cloud Climatology Project (ISCCP) Regional Experiment (FIRE)Arctic Cloud Experiment (ACE)Surface Heat Budget of the Arctic Ocean (SHEBA) campaign provide a unique opportunity to test understanding of cloud ice formation. Under the microphysically simple conditions observed (apparently negligible ice aggregation, sublimation, and multiplication), the only expected source of new ice crystals is activation of heterogeneous ice nuclei (IN) and the only sink is sedimentation. Large-eddy simulations with size-resolved microphysics are initialized with IN number concentration N(sub IN) measured above cloud top, but details of IN activation behavior are unknown. If activated rapidly (in deposition, condensation, or immersion modes), as commonly assumed, IN are depleted from the well-mixed boundary layer within minutes. Quasi-equilibrium ice number concentration N(sub i) is then limited to a small fraction of overlying N(sub IN) that is determined by the cloud-top entrainment rate w(sub e) divided by the number-weighted ice fall speed at the surface v(sub f). Because w(sub c) 10 cm/s, N(sub i)/N(sub IN)<< 1. Such conditions may be common for this cloud type, which has implications for modeling IN diagnostically, interpreting measurements, and quantifying sensitivity to increasing N(sub IN) (when w(sub e)/v(sub f)< 1, entrainment rate limitations serve to buffer cloud system response). To reproduce observed ice crystal size distributions and cloud radar reflectivities with rapidly consumed IN in this case, the measured above-cloud N(sub IN) must be multiplied by approximately 30. However, results are sensitive to assumed ice crystal properties not constrained by measurements. In addition, simulations do not reproduce the pronounced mesoscale heterogeneity in radar reflectivity that is observed.

  8. The effect of growth phase on the surface properties of three oleaginous microalgae (Botryococcus sp. FACGB-762, Chlorella sp. XJ-445 and Desmodesmus bijugatus XJ-231).

    Science.gov (United States)

    Xia, Ling; Huang, Rong; Li, Yinta; Song, Shaoxian

    2017-01-01

    The effects of growth phase on the lipid content and surface properties of oleaginous microalgae Botryococcus sp. FACGB-762, Chlorella sp. XJ-445 and Desmodesmus bijugatus XJ-231 were investigated in this study. The results showed that throughout the growth phases, the lipid content of microalgae increased. The surface properties like particle size, the degree of hydrophobicity, and the total concentration of functional groups increased while net surface zeta potential decreased. The results suggested that the growth stage had significant influence not only on the lipid content but also on the surface characteristics. Moreover, the lipid content was significantly positively related to the concentration of hydroxyl functional groups in spite of algal strains or growth phases. These results provided a basis for further studies on the refinery process using oleaginous microalgae for biofuel production.

  9. Photosynthetic Entrainment of the Circadian Clock Facilitates Plant Growth under Environmental Fluctuations: Perspectives from an Integrated Model of Phase Oscillator and Phloem Transportation

    Directory of Open Access Journals (Sweden)

    Takayuki Ohara

    2017-10-01

    Full Text Available Plants need to avoid carbon starvation and resultant growth inhibition under fluctuating light environments to ensure optimal growth and reproduction. As diel patterns of carbon metabolism are influenced by the circadian clock, appropriate regulation of the clock is essential for plants to properly manage their carbon resources. For proper adjustment of the circadian phase, higher plants utilize environmental signals such as light or temperature and metabolic signals such as photosynthetic products; the importance of the latter as phase regulators has been recently elucidated. A mutant of Arabidopsis thaliana that is deficient in phase response to sugar has been shown, under fluctuating light conditions, to be unable to adjust starch turnover and to realize carbon homeostasis. Whereas, the effects of light entrainment on growth and survival of higher plants are well studied, the impact of phase regulation by sugar remains unknown. Here we show that endogenous sugar entrainment facilitates plant growth. We integrated two mathematical models, one describing the dynamics of carbon metabolism in A. thaliana source leaves and the other growth of sink tissues dependent on sucrose translocation from the source. The integrated model predicted that sugar-sensitive plants grow faster than sugar-insensitive plants under constant as well as changing photoperiod conditions. We found that sugar entrainment enables efficient carbon investment for growth by stabilizing sucrose supply to sink tissues. Our results highlight the importance of clock entrainment by both exogenous and endogenous signals for optimizing growth and increasing fitness.

  10. Formation of U(IV) Nanoparticles and Their Growth Mechanism in Mildly Acidic Aqueous Phases

    Energy Technology Data Exchange (ETDEWEB)

    Cha, Wan Sik; Kim, Sun Tae; Cho, Hye Ryun; Jung, Euo Chang [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    Previous studies suggest that U(IV) nanoparticle (NP) formation is one of key steps in mineralization or immobilization of uranium which can be mediated either by microbes or by abiotic geochemical reactions. Colloidal NPs in a groundwater system are potential carrier phases influencing RN migration in subsurface environment. However, the mechanism of U(IV) NP formation and the potential reaction intermediates during this solid phase formation process have not been elucidated in detail so far. In this study we attempted to examine the U(IV) nanoparticle formation reactions preceded by the hydrolysis of U{sup 4+} at different pHs, concentrations and temperatures. The kinetics of U(IV) NP formation from dissolved U(IV) species was monitored under mildly acidic conditions (pH 2 ∼ 3) mainly by using UV-Vis absorption spectrophotometry. Dynamic light scattering (DLS) analysis, nanoparticle tracking analysis (NTA) and transmission electron microscopy (TEM) were used to characterize the NPs produced during the reactions. The results demonstrate that the U(IV) NP formation process is very sensitive toward temperature variation. The main outcome of this study is the discovery of the autocatalytic nature of U(IV) NP formation from the supersaturated U(OH){sup 3+} solution in a mildly acidic aqueous solution. The structure of reaction intermediates is proposed to contain oxide linkage. In the presentation the proposed mechanism of the U(IV) NP formation reaction and the properties of primary NPs and their clusters will be discussed in detail.

  11. Sweet passion fruit (Passiflora alata Curtis germination: Phases and effect of plant growth regulator

    Directory of Open Access Journals (Sweden)

    Sheila Zambello de Pinho

    2008-09-01

    Full Text Available This work aimed to characterize Passiflora alata germination phases and evaluate the effects of GA3 and GA4+7, associated with phenylmethylaminepurine, on P. alata seed germination. Two experiments were conducted. In the first, two treatments were carried out: seeds submerged in distilled water in a Becker and seeds conditioned in containers on filter paper soaked in distilled water; five replications of 25 seeds were used. The moisture level and the percentage of germination (%G were evaluated. In the second, six treatments and five replications of 25 seeds for each regulator were used. The seeds were imbibed in 0, 50, 100, 150, 200 and 250mg.L-1 of GA3 and GA4+7, associated with to phenylmethylaminepurine, for 11 hours. The seeds were sown in black containers and deposited in to the germination chamber. The numbers of germinated and dormant seeds were evaluated daily. The percentage of germination, the percentage of dormant seeds, and the mean germination time (TMG were estimated. Significant differences in the germination phases between the methods were verified. The germination was affected by the regulators with an increase in the percentage of germination and a reduction in the mean germination time. The highest values were observed with 250mg.L-1 of GA4+7 plus phenylmethylaminepurine.

  12. Automated Online Solid-Phase Derivatization for Sensitive Quantification of Endogenous S-Nitrosoglutathione and Rapid Capture of Other Low-Molecular-Mass S-Nitrosothiols.

    Science.gov (United States)

    Wang, Xin; Garcia, Carlos T; Gong, Guanyu; Wishnok, John S; Tannenbaum, Steven R

    2018-02-06

    S-Nitrosothiols (RSNOs) constitute a circulating endogenous reservoir of nitric oxide and have important biological activities. In this study, an online coupling of solid-phase derivatization (SPD) with liquid chromatography-mass spectrometry (LC-MS) was developed and applied in the analysis of low-molecular-mass RSNOs. A derivatizing-reagent-modified polymer monolithic column was prepared and adapted for online SPD-LC-MS. Analytes from the LC autosampler flowed through the monolithic column for derivatization and then directly into the LC-MS for analysis. This integration of the online derivatization, LC separation, and MS detection facilitated system automation, allowing rapid, laborsaving, and sensitive detection of RSNOs. S-Nitrosoglutathione (GSNO) was quantified using this automated online method with good linearity (R 2 = 0.9994); the limit of detection was 0.015 nM. The online SPD-LC-MS method has been used to determine GSNO levels in mouse samples, 138 ± 13.2 nM of endogenous GSNO was detected in mouse plasma. Besides, the GSNO concentrations in liver (64.8 ± 11.3 pmol/mg protein), kidney (47.2 ± 6.1 pmol/mg protein), heart (8.9 ± 1.8 pmol/mg protein), muscle (1.9 ± 0.3 pmol/mg protein), hippocampus (5.3 ± 0.9 pmol/mg protein), striatum (6.7 ± 0.6 pmol/mg protein), cerebellum (31.4 ± 6.5 pmol/mg protein), and cortex (47.9 ± 4.6 pmol/mg protein) were also successfully quantified. When the derivatization was performed within 8 min, followed by LC-MS detection, samples could be rapidly analyzed compared with the offline manual method. Other low-molecular-mass RSNOs, such as S-nitrosocysteine and S-nitrosocysteinylglycine, were captured by rapid precursor-ion scanning, showing that the proposed method is a potentially powerful tool for capture, identification, and quantification of RSNOs in biological samples.

  13. Saccharomyces cerevisiae biofilm tolerance towards systemic antifungals depends on growth phase

    DEFF Research Database (Denmark)

    Bojsen, Rasmus Kenneth; Regenberg, Birgitte; Folkesson, Sven Anders

    2014-01-01

    Background : Biofilm-forming Candida species cause infections that can be difficult to eradicate, possibly because of antifungal drug tolerance mechanisms specific to biofilms. In spite of decades of research, the connection between biofilm and drug tolerance is not fully understood. Results : We...... used Saccharomyces cerevisiae as a model for drug susceptibility of yeast biofilms. Confocal laser scanning microscopy showed that S. cerevisiae and C. glabrata form similarly structured biofilms and that the viable cell numbers were significantly reduced by treatment of mature biofilms...... with amphotericin B but not voriconazole, flucytosine, or caspofungin. We showed that metabolic activity in yeast biofilm cells decreased with time, as visualized by FUN-1 staining, and mature, 48-hour biofilms contained cells with slow metabolism and limited growth. Time-kill studies showed that in exponentially...