Science.gov

Sample records for additional studies investigating

  1. Study on the interaction of the toxic food additive carmoisine with serum albumins: a microcalorimetric investigation.

    PubMed

    Basu, Anirban; Kumar, Gopinatha Suresh

    2014-05-30

    The interaction of the synthetic azo dye and food colorant carmoisine with human and bovine serum albumins was studied by microcalorimetric techniques. A complete thermodynamic profile of the interaction was obtained from isothermal titration calorimetry studies. The equilibrium constant of the complexation process was of the order of 10(6)M(-1) and the binding stoichiometry was found to be 1:1 with both the serum albumins. The binding was driven by negative standard molar enthalpy and positive standard molar entropy contributions. The binding affinity was lower at higher salt concentrations in both cases but the same was dominated by mostly non-electrostatic forces at all salt concentrations. The polyelectrolytic forces contributed only 5-8% of the total standard molar Gibbs energy change. The standard molar enthalpy change enhanced whereas the standard molar entropic contribution decreased with rise in temperature but they compensated each other to keep the standard molar Gibbs energy change almost invariant. The negative standard molar heat capacity values suggested the involvement of a significant hydrophobic contribution in the complexation process. Besides, enthalpy-entropy compensation phenomenon was also observed in both the systems. The thermal stability of the serum proteins was found to be remarkably enhanced on binding to carmoisine. PMID:24742664

  2. Theoretical and experimental investigation of additive drag

    NASA Technical Reports Server (NTRS)

    Sibulkin, Merwin

    1954-01-01

    The significance of additive drag is discussed and equations for determining its approximate value are derived for annular and open-nose inlets. Charts are presented giving values of additive drag coefficient over a range of free-stream Mach numbers for open and for annular-nose inlets with conical flow at the inlet. The effects on additive drag of variable inlet-total-pressure recovery and static pressures on the centerbody are investigated and an analytical method of predicting the variation of pressure on the centerbody with mass-flow ratio is given. Experimental additive-drag values are presented for a series of 20 degree and 25 degree cone half-angle inlets and one open-nose inlet operating at free-stream Mach numbers of 1.8 and 1.6. A comparison with the theoretical values of additive drag shows excellent agreement for the open-nose inlet and moderately good agreement for the annular inlets. (author)

  3. Addition polyimide end cap study

    NASA Technical Reports Server (NTRS)

    St.clair, T. L.

    1980-01-01

    The characterization of addition polyimides with various end caps for adhesive applications at 120-250 C environments is discussed. Oligometric polyimides were prepared from 3,3',4,4'-benzophenone tetracarboxylic dianhydride and 3,3'-methylenedianiline which were end-capped with functionally reactive moities which cause crosslinking when the oligomers are heated to 200-400 C. The syntheses of the oligomers are outlined. The thermolysis of the oligomers was studied by differential scanning calorimetry and the resulting polymers were characterized by differential thermal analysis and adhesive performance. The adhesive data include lap shear strengths on titanium 6-4 adherends both before and after aging for 1000 hours at 121 C and/or 232 C.

  4. Additional Technologies and Investigations for Provision of Future Aeronautical Communications

    NASA Technical Reports Server (NTRS)

    Gilbert, Tricia; Jin, Jenny; Berger, Jason; Henriksen, Steve

    2008-01-01

    The following NASA Contractor Report documents the in-depth studies on select technologies that could support long-term aeronautical mobile communications operating concepts. This work was performed during the third and final phase of NASA s Technology Assessment for the Federal Aviation Administration (FAA)/EUROCONTROL Future Communications Study (FCS) under a multiyear NASA contract. It includes the associated findings of ITT Corporation and NASA Glenn Research Center to the FAA as of the end of May 2007. The activities documented in this report focus on three final technology candidates identified by the United States, and were completed before sufficient information about two additional technology candidates proposed by EUROCONTROL was made available. A separate report to be published by NASA/CR-2008-215144, entitled Final Report on Technology Investigations for Provision of Future Aeronautical Communications will include an assessment of all five final candidate technologies considered by the U.S. agencies (FAA and NASA) and EUROCONTROL. It will also provide an overview of the entire technology assessment process, including final recommendations. All three phases of this work were performed in compliance with the Terms of Reference for the Action Plan number 17 (AP-17) cooperative research agreement among EUROCONTROL, FAA, and NASA along with the general guidance of the FAA and EUROCONTROL available throughout this study.

  5. Additional Investigations of Ice Shape Sensitivity to Parameter Variations

    NASA Technical Reports Server (NTRS)

    Miller, Dean R.; Potapczuk, Mark G.; Langhals, Tammy J.

    2006-01-01

    A second parameter sensitivity study was conducted at the NASA Glenn Research Center's Icing Research Tunnel (IRT) using a 36 in. chord (0.91 m) NACA-0012 airfoil. The objective of this work was to further investigate the feasibility of using ice shape feature changes to define requirements for the simulation and measurement of SLD and appendix C icing conditions. A previous study concluded that it was feasible to use changes in ice shape features (e.g., ice horn angle, ice horn thickness, and ice shape mass) to detect relatively small variations in icing spray condition parameters (LWC, MVD, and temperature). The subject of this current investigation extends the scope of this previous work, by also examining the effect of icing tunnel spray-bar parameter variations (water pressure, air pressure) on ice shape feature changes. The approach was to vary spray-bar water pressure and air pressure, and then evaluate the effects of these parameter changes on the resulting ice shapes. This paper will provide a description of the experimental method, present selected experimental results, and conclude with an evaluation of these results.

  6. An investigation of an additional layer during sunset period

    NASA Astrophysics Data System (ADS)

    Zhao, Biqiang; Wan, Weixing

    F3 layer is a very common feature within ±10° of the magnetic equatorial ionosphere in the daytime. According to Balan et al. (1998), the F3 layer occurs mainly during the morning-noon ( 08:30 -16:30 LT) period due to the combined effect of the upward EB drift and the neutral wind that provides vertically upward plasma drifts at and above the F2 layer. The F3 layer occurs not only in summer (higher occurrences) months but also in winter months, and to be observed less frequently with increasing solar activity. In this study, characteristic of the sunset F3 layer is first investigated from an analysis of a solar cycle ionosonde data (1995-2009) over Jicamarca (-12.0° , 283.2° , Dip 0.284-1.12° ) and ionosonde data (2004-2007) over Kwajalein (9.0° , 167° , Dip 7.7° ). Evidence shows that the local time distribution of the occurrence of the F3 layer can extend to the post-sunset time (18-21 LT) during the geomagnetic quiet period. The sunset F3 layer has a strong seasonal dependence which occurs mainly during the November-February months. Unlike the daytime F3 layer, occurrences of the sunset F3 layer clearly increases with increasing solar activity and the virtue height of the bottom side of the F3 layer statistically increases from 620 km to 1000 km. The occurrence of the sunset F3 layer at Kwajalein equatorial station is much less than that at Jicamarca. These features of the dependence on the season, solar activity and the longitude are clearly related to the geomagnetic distribution of the equatorial pre-reversal drift.

  7. Additives

    NASA Technical Reports Server (NTRS)

    Smalheer, C. V.

    1973-01-01

    The chemistry of lubricant additives is discussed to show what the additives are chemically and what functions they perform in the lubrication of various kinds of equipment. Current theories regarding the mode of action of lubricant additives are presented. The additive groups discussed include the following: (1) detergents and dispersants, (2) corrosion inhibitors, (3) antioxidants, (4) viscosity index improvers, (5) pour point depressants, and (6) antifouling agents.

  8. Structure Property Studies for Additively Manufactured Parts

    SciTech Connect

    Milenski, Helen M; Schmalzer, Andrew Michael; Kelly, Daniel

    2015-08-17

    Since the invention of modern Additive Manufacturing (AM) processes engineers and designers have worked hard to capitalize on the unique building capabilities that AM allows. By being able to customize the interior fill of parts it is now possible to design components with a controlled density and customized internal structure. The creation of new polymers and polymer composites allow for even greater control over the mechanical properties of AM parts. One of the key reasons to explore AM, is to bring about a new paradigm in part design, where materials can be strategically optimized in a way that conventional subtractive methods cannot achieve. The two processes investigated in my research were the Fused Deposition Modeling (FDM) process and the Direct Ink Write (DIW) process. The objectives of the research were to determine the impact of in-fill density and morphology on the mechanical properties of FDM parts, and to determine if DIW printed samples could be produced where the filament diameter was varied while the overall density remained constant.

  9. A study protocol of a randomised controlled trial incorporating a health economic analysis to investigate if additional allied health services for rehabilitation reduce length of stay without compromising patient outcomes

    PubMed Central

    2010-01-01

    Background Reducing patient length of stay is a high priority for health service providers. Preliminary information suggests additional Saturday rehabilitation services could reduce the time a patient stays in hospital by three days. This large trial will examine if providing additional physiotherapy and occupational therapy services on a Saturday reduces health care costs, and improves the health of hospital inpatients receiving rehabilitation compared to the usual Monday to Friday service. We will also investigate the cost effectiveness and patient outcomes of such a service. Methods/Design A randomised controlled trial will evaluate the effect of providing additional physiotherapy and occupational therapy for rehabilitation. Seven hundred and twelve patients receiving inpatient rehabilitation at two metropolitan sites will be randomly allocated to the intervention group or control group. The control group will receive usual care physiotherapy and occupational therapy from Monday to Friday while the intervention group will receive the same amount of rehabilitation as the control group Monday to Friday plus a full physiotherapy and occupational therapy service on Saturday. The primary outcomes will be patient length of stay, quality of life (EuroQol questionnaire), the Functional Independence Measure (FIM), and health utilization and cost data. Secondary outcomes will assess clinical outcomes relevant to the goals of therapy: the 10 metre walk test, the timed up and go test, the Personal Care Participation Assessment and Resource Tool (PC PART), and the modified motor assessment scale. Blinded assessors will assess outcomes at admission and discharge, and follow up data on quality of life, function and health care costs will be collected at 6 and 12 months after discharge. Between group differences will be analysed with analysis of covariance using baseline measures as the covariate. A health economic analysis will be carried out alongside the randomised

  10. Additional EIPC Study Analysis. Final Report

    SciTech Connect

    Hadley, Stanton W; Gotham, Douglas J.; Luciani, Ralph L.

    2014-12-01

    Between 2010 and 2012 the Eastern Interconnection Planning Collaborative (EIPC) conducted a major long-term resource and transmission study of the Eastern Interconnection (EI). With guidance from a Stakeholder Steering Committee (SSC) that included representatives from the Eastern Interconnection States Planning Council (EISPC) among others, the project was conducted in two phases. Phase 1 involved a long-term capacity expansion analysis that involved creation of eight major futures plus 72 sensitivities. Three scenarios were selected for more extensive transmission- focused evaluation in Phase 2. Five power flow analyses, nine production cost model runs (including six sensitivities), and three capital cost estimations were developed during this second phase. The results from Phase 1 and 2 provided a wealth of data that could be examined further to address energy-related questions. A list of 14 topics was developed for further analysis. This paper brings together the earlier interim reports of the first 13 topics plus one additional topic into a single final report.

  11. 21 CFR 71.37 - Exemption of color additives for investigational use.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Exemption of color additives for investigational... SERVICES GENERAL COLOR ADDITIVE PETITIONS Administrative Action on Petitions § 71.37 Exemption of color additives for investigational use. (a) A shipment or other delivery of a color additive or of a food,...

  12. 21 CFR 71.37 - Exemption of color additives for investigational use.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Exemption of color additives for investigational... SERVICES GENERAL COLOR ADDITIVE PETITIONS Administrative Action on Petitions § 71.37 Exemption of color additives for investigational use. (a) A shipment or other delivery of a color additive or of a food,...

  13. 21 CFR 71.37 - Exemption of color additives for investigational use.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 1 2013-04-01 2013-04-01 false Exemption of color additives for investigational use. 71.37 Section 71.37 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL COLOR ADDITIVE PETITIONS Administrative Action on Petitions § 71.37 Exemption of color additives for investigational use. (a)...

  14. Thermodynamic Effect of Platinum Addition to beta-NiAl: An Initial Investigation

    NASA Technical Reports Server (NTRS)

    2005-01-01

    An initial investigation was conducted to determine the effect of platinum addition on the activities of aluminum and nickel in beta-NiAl(Pt) over the temperature range 1354 to 1692 K. These measurements were made with a multiple effusion-cell configured mass spectrometer (multi-cell KEMS). The results of this study show that Pt additions act to decreased alpha(Al) and increased the alpha(Ni) in beta-NiAl(Pt) for constant X(sub Ni)/X(sub Al) approx. = 1.13, while at constant X(sub Al) the affect of Pt on Al is greatly reduced. The measured partial enthalpies of mixing indicate Al-atoms have a strong self interaction while Ni- and Pt-atoms in have similar interactions with Al-atoms. Conversely the binding of Ni-atoms in beta-NiAl decreases with Pt addition independent of Al concentration. These initial results prove the technique can be applied to the Ni-Al-Pt system but more activity measurements are required to fully understand the thermodynamics of this system and how Pt additions improved the scaling behavior of nickel-based superalloys. In addition, with the choice of a suitable oxide material for the effusion-cell, the "closed" isothermal nature of the effusion-cell allows the direct investigation of an alloy-oxide equilibrium which resembles the "local-equilibrium" description of the metal-scale interface observed during high temperature oxidation. It is proposed that with an Al(l) + Al2O3(s) experimental reference state together with the route measurement of the relative partial-pressures of Al(g) and Al2O(g) allows the activities of O and Al2O3 to be determined along with the activities of Ni and Al. These measurements provide a direct method of investigating the thermodynamics of the metal-scale interface of a TGO-scale.

  15. Electrostatic Levitation for Studies of Additive Manufactured Materials

    NASA Technical Reports Server (NTRS)

    SanSoucie, Michael P.; Rogers, Jan R.; Tramel, Terri

    2014-01-01

    The electrostatic levitation (ESL) laboratory at NASA's Marshall Space Flight Center is a unique facility for investigators studying high temperature materials. The laboratory boasts two levitators in which samples can be levitated, heated, melted, undercooled, and resolidified. Electrostatic levitation minimizes gravitational effects and allows materials to be studied without contact with a container or instrumentation. The lab also has a high temperature emissivity measurement system, which provides normal spectral and normal total emissivity measurements at use temperature. The ESL lab has been instrumental in many pioneering materials investigations of thermophysical properties, e.g., creep measurements, solidification, triggered nucleation, and emissivity at high temperatures. Research in the ESL lab has already led to the development of advanced high temperature materials for aerospace applications, coatings for rocket nozzles, improved medical and industrial optics, metallic glasses, ablatives for reentry vehicles, and materials with memory. Modeling of additive manufacturing materials processing is necessary for the study of their resulting materials properties. In addition, the modeling of the selective laser melting processes and its materials property predictions are also underway. Unfortunately, there is very little data for the properties of these materials, especially of the materials in the liquid state. Some method to measure thermophysical properties of additive manufacturing materials is necessary. The ESL lab is ideal for these studies. The lab can provide surface tension and viscosity of molten materials, density measurements, emissivity measurements, and even creep strength measurements. The ESL lab can also determine melting temperature, surface temperatures, and phase transition temperatures of additive manufactured materials. This presentation will provide background on the ESL lab and its capabilities, provide an approach to using the ESL

  16. 21 CFR 71.37 - Exemption of color additives for investigational use.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ..., or cosmetic containing such a color additive for investigational use by experts qualified to determine safety shall be exempt from the requirements of section 402(c), 501(a), or 601(e) of the act, provided that the color additive or the food, drug, or cosmetic containing the color additive bears a...

  17. 21 CFR 71.37 - Exemption of color additives for investigational use.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ..., or cosmetic containing such a color additive for investigational use by experts qualified to determine safety shall be exempt from the requirements of section 402(c), 501(a), or 601(e) of the act, provided that the color additive or the food, drug, or cosmetic containing the color additive bears a...

  18. Making intelligent systems team players: Additional case studies

    NASA Technical Reports Server (NTRS)

    Malin, Jane T.; Schreckenghost, Debra L.; Rhoads, Ron W.

    1993-01-01

    Observations from a case study of intelligent systems are reported as part of a multi-year interdisciplinary effort to provide guidance and assistance for designers of intelligent systems and their user interfaces. A series of studies were conducted to investigate issues in designing intelligent fault management systems in aerospace applications for effective human-computer interaction. The results of the initial study are documented in two NASA technical memoranda: TM 104738 Making Intelligent Systems Team Players: Case Studies and Design Issues, Volumes 1 and 2; and TM 104751, Making Intelligent Systems Team Players: Overview for Designers. The objective of this additional study was to broaden the investigation of human-computer interaction design issues beyond the focus on monitoring and fault detection in the initial study. The results of this second study are documented which is intended as a supplement to the original design guidance documents. These results should be of interest to designers of intelligent systems for use in real-time operations, and to researchers in the areas of human-computer interaction and artificial intelligence.

  19. Additional Treatments Offer Little Benefit for Pancreatic Cancer: Study

    MedlinePlus

    ... 158633.html Additional Treatments Offer Little Benefit for Pancreatic Cancer: Study Neither extra chemotherapy drug nor add-on ... 2016 (HealthDay News) -- Additional treatments for locally advanced pancreatic cancer don't appear to boost survival, a new ...

  20. A Study of Additional Costs of Second Language Instruction.

    ERIC Educational Resources Information Center

    McEwen, Nelly

    A study was conducted whose primary aim was to identify and explain additional costs incurred by Alberta, Canada school jurisdictions providing second language instruction in 1980. Additional costs were defined as those which would not have been incurred had the second language program not been in existence. Three types of additional costs were…

  1. Experimental Study of Additives on Viscosity biodiesel at Low Temperature

    NASA Astrophysics Data System (ADS)

    Fajar, Berkah; Sukarno

    2015-09-01

    An experimental investigation was performed to find out the viscosity of additive and biodiesel fuel mixture in the temperature range from 283 K to 318 K. Solutions to reduce the viscosity of biodiesel is to add the biodiesel with some additive. The viscosity was measured using a Brookfield Rheometer DV-II. The additives were the generic additive (Diethyl Ether/DDE) and the commercial additive Viscoplex 10-330 CFI. Each biodiesel blends had a concentration of the mixture: 0.0; 0.25; 0.5; 0.75; 1.0; and 1.25% vol. Temperature of biodiesel was controlled from 40°C to 0°C. The viscosity of biodiesel and additive mixture at a constant temperature can be approximated by a polynomial equation and at a constant concentration by exponential equation. The optimum mixture is at 0.75% for diethyl ether and 0.5% for viscoplex.

  2. Biomechanical investigation into the structural design of porous additive manufactured cages using numerical and experimental approaches.

    PubMed

    Tsai, Pei-I; Hsu, Ching-Chi; Chen, San-Yuan; Wu, Tsung-Han; Huang, Chih-Chieh

    2016-09-01

    Traditional solid cages have been widely used in posterior lumbar interbody fusion (PLIF) surgery. However, solid cages significantly affect the loading mechanism of the human spine due to their extremely high structural stiffness. Previous studies proposed and investigated porous additive manufactured (AM) cages; however, their biomechanical performances were analyzed using oversimplified bone-implant numerical models. Thus, the aim of this study was to investigate the outer shape and inner porous structure of the AM cages. The outer shape of the AM cages was discovered using a simulation-based genetic algorithm; their inner porous structure was subsequently analyzed parametrically using T10-S1 multilevel spine models. Finally, six types of the AM cages, which were manufactured using selective laser melting, were tested to validate the numerical outcomes. The subsidence resistance of the optimum design was superior to the conventional cage designs. A porous AM cage with a pillar diameter of 0.4mm, a pillar angle of 40°, and a porosity of between 69% and 80% revealed better biomechanical performances. Both the numerical and experimental outcomes can help surgeons to understand the biomechanics of PLIF surgery combined with the use of AM cages. PMID:27392226

  3. Investigation of possible causes of the additional torque on the yacht's rudder

    NASA Astrophysics Data System (ADS)

    Lubomir, Soukup; Jaroslav, Stigler; Abdellah, Kharicha

    2016-03-01

    The present article deals with investigation of possible causes of the additional torque on the yacht's rudder. One of the most important aspect for design of yachts are the symmetric conditions of all parts, which are located under water level and concentricity of the ship's screw, rudder and keel relative to the hull. These symmetric and concentricity conditions have a major impact on the resulting dynamic properties of the ships. They have either substantial impact on the overall efficiency of installed engine and ship's screw. As the result of poorly designed above mentioned parts, there can be an unsolicited additional torque on the yacht's rudder and higher consumption of the fuel. Last but not least of these problems leads to poor controllability and discomfort within steering. This article is focused on the investigation of possible causes of the additional torque on the yacht's rudder.

  4. Preliminary Investigation of Keyhole Phenomena during Single Layer Fabrication in Laser Additive Manufacturing of Stainless Steel

    NASA Astrophysics Data System (ADS)

    Matilainen, Ville-Pekka; Piili, Heidi; Salminen, Antti; Nyrhilä, Olli

    Laser additive manufacturing (LAM) is a fabrication technology that enables production of complex parts from metallic materials with mechanical properties comparable to conventionally manufactured parts. In the LAM process, parts are manufactured by melting metallic powder layer-by-layer with a laser beam. This manufacturing technology is nowadays called powder bed fusion (PBF) according to the ASTM F2792-12a standard. This strategy involves several different independent and dependent thermal cycles, all of which have an influence on the final properties of the manufactured part. The quality of PBF parts depends strongly on the characteristics of each single laser-melted track and each single layer. This study consequently concentrates on investigating the effects of process parameters such as laser power on single track and layer formation and laser-material interaction phenomena occurring during the PBF process. Experimental tests were done with two different machines: a modified research machine based on an EOS EOSINT M-series system and an EOS EOSINT M280 system. The material used was EOS stainless steel 17-4 PH. Process monitoring was done with an active illuminated high speed camera system. After microscopy analysis, it was concluded that a keyhole can form during laser additive manufacturing of stainless steel. It was noted that heat input has an important effect on the likelihood of keyhole formation. The threshold intensity value for keyhole formation of 106 W/cm2 was exceeded in all manufactured single tracks. Laser interaction time was found to have an effect on penetration depth and keyhole formation, since the penetration depth increased with increased laser interaction time. It was also concluded that active illuminated high speed camera systems are suitable for monitoring of the manufacturing process and facilitate process control.

  5. Investigation of the additive induced doping effects in gelcast soft lead zirconate titanate ceramics

    SciTech Connect

    Guo Dong; Cai Kai; Li Longtu; Gui Zhilun

    2009-09-01

    Due to the high sensitivity of the electrical properties of electronic ceramics to various factors, knowledge about the possible influence of the processing procedure on their electrical performance is critical for applying a new technique to the fabrication of the materials. In this study, various electrical parameters, complex impedance spectra, ferroelectric hysteresis loops, and microstructures of soft lead zirconate titanate (PZT) ceramics formed by the gelcasting technique from suspensions with various dispersants were investigated in comparison with those of the conventional dry pressed ones. We found that the sodium ion, which is the main cation in many commercial surfactants, exhibited obvious hard doping effects; thus causing deteriorated performance of the gelcast PZT ceramics. While a certain impurity ion introduced by a dispersant was also found to induce soft doping characteristics and improve the electrical performance of the materials. The results suggest that the doping effects of the metal ions or impurities introduced by the dispersants, or other additives, should be generally considered for applying a wet processing technique to forming multicomponent electronic ceramics.

  6. Investigating calcium polyphosphate addition to a conventional calcium phosphate cement for bone-interfacing applications

    NASA Astrophysics Data System (ADS)

    Krausher, Jennifer Lynn

    Calcium phosphate cements (CPCs) are of great interest in bone regeneration applications because of their biocompatibility and osteoconductivity, and as delivery vehicles for therapeutics; however, delivery applications have been limited by adverse interactions between therapeutics and the cement setting reaction. Amorphous calcium polyphosphate (CPP) yields a biodegradable material with a demonstrated drug delivery capacity following appropriate processing. The incorporation of drug-loaded CPP into a CPC is under consideration as a method of minimizing adverse interactions and extending drug release. This thesis represents the first investigation into the effects of CPP addition on the properties, setting and antibiotic release profile of a conventional apatitic calcium phosphate cement. As-made, gelled and vancomycin-loaded CPP particulate were added to the powder component of a conventional dicalcium phosphate/tetracalcium phosphate CPC. The setting behaviour, set properties and microstructure of the resulting CPP-CPCs were evaluated with setting time testing (Gilmore needle method), pH testing, mechanical testing, SEM imaging, XRD and FTIR analysis. In vitro degradation and elution behaviour were evaluated by monitoring calcium release (atomic absorbance spectroscopy), mechanical strength and vancomycin release (UV-visual spectrophotometry). CPP addition was found to increase the setting time, reduce the mechanical strength and inhibit the conversion of the CPC starting powders to the set apatitic phase. The most likely mechanism for the observed effect of CPP addition was the adsorption of polyphosphate chains on the particle surfaces, which would inhibit the dissolution of the starting powders and the conversion of apatite precursor phases to apatite, leading to reduced mechanical properties. The detrimental effects of CPP were reduced by limiting the CPP fraction to less than a few weight per cent and increasing the size of the CPP particulate. CPP

  7. Study of wood plastic composite in the presence of nitrogen containing additives

    NASA Astrophysics Data System (ADS)

    Ali, K. M. Idriss; Khan, Mubarak A.; Husain, M. M.

    1994-10-01

    Effect of nitrogen-containing additives in the study of wood plastic composites of MMA with simul and mango wood of Bangladesh has been investigated. Nine different additives were used and the additives containing carboamide group induce the highest tensile strength to the composite.

  8. Investigation of an effervescent additive as porogenic agent for bone cement macroporosity.

    PubMed

    Hesaraki, Saeed; Sharifi, Davood

    2007-01-01

    Calcium phosphate cements (CPCs) are biocompatible and osteoconductive materials used in dental, craniofacial and orthopaedic applications. One of the most important advantages of these materials is their replacement with bone followed by resorption. Already several attempts have been made to improve the resorption behaviour of calcium phosphate cements by increasing the porosity of the material. In this investigation a mixture of NaHCO(3) and citric acid monohydrate was added to the apatite cement component as an effervescent additive for producing interconnected macropores into the cement matrix. Mercury intrusion porosimetry was employed to determine pore volume and pore size distribution in the calcium phosphate cement (CPC) samples. Results showed that addition of only 10 wt % of the effervescent additive (based on the cement powder) to the CPC components lead to producing about 20 V % macropores (with the size of 10 to 1000 mum) into the cement structure. The setting time was measured in an incubator at 37 degrees C and decreased from 40 min for additive-free CPC to about 14 min for CPC containing effervescent additive. Other properties of the CPCs such as compressive strength, phase composition, microstructure morphology and dissolution behavior were evaluated after immersing them in a simulated body fluid solution. The results showed that the rate of formation of poor crystalline apatite phase have been improved by production of macroporosity into the cement matrix. PMID:17264385

  9. Investigation of effect of particle size and rumen fluid addition on specific methane yields of high lignocellulose grass silage.

    PubMed

    Wall, D M; Straccialini, B; Allen, E; Nolan, P; Herrmann, C; O'Kiely, P; Murphy, J D

    2015-09-01

    This work examines the digestion of advanced growth stage grass silage. Two variables were investigated: particle size (greater than 3 cm and less than 1cm) and rumen fluid addition. Batch studies indicated particle size and rumen fluid addition had little effect on specific methane yields (SMYs). In continuous digestion of 3 cm silage the SMY was 342 and 343 L CH4 kg(-1)VS, respectively, with and without rumen fluid addition. However, digester operation was significantly affected through silage floating on the liquor surface and its entanglement in the mixing system. Digestion of 1cm silage with no rumen fluid addition struggled; volatile fatty acid concentrations rose and SMYs dropped. The best case was 1cm silage with rumen fluid addition, offering higher SMYs of 371 L CH4 kg(-1)VS and stable operation throughout. Thus, physical and biological treatments benefited continuous digestion of high fibre grass silage. PMID:26038332

  10. Investigation in the use of plasma arc welding and alternative feedstock delivery method in additive manufacture

    NASA Astrophysics Data System (ADS)

    Alhuzaim, Abdullah F.

    The work conducted for this thesis was to investigate the use of plasma arc welding (PAW) and steel shot as a means of additive manufacturing. A robotic PAW system and automatic shot feeder were used to manufacture linear walls approximately 100 mm long by 7 mm wide and 20 mm tall. The walls were built, layer-by-layer, on plain carbon steel substrate by adding individual 2.5 mm diameter plain carbon steel shot. Each layer was built, shot-by-shot, using a pulse of arc current to form a molten pool on the deposit into which each shot was deposited and melted. The deposition rate, a measure of productivity, was approximately 50 g/hour. Three walls were built using the same conditions except for the deposit preheat temperature prior to adding each new layer. The deposit preheat temperature was controlled by allowing the deposit to cool after each layer for an amount of time called the inter-layer wait time. The walls were sectioned and grain size and hardness distribution were measured as a function of wall height. The results indicated that, for all specimens, deposit grain size increased and hardness decreased as wall height increased. Furthermore, average grain size decreased and hardness increased as interlayer wait time increased. An analytical heat flow model was developed to study the influence of interlayer wait time on deposit temperature and therefore grain size and hardness. The results of the model indicated that as wall height increased, the rate of deposit heat removal by conduction to the substrate decreased leading to a higher preheat temperature after a fixed interlayer wait time causing grain size to increase as wall height increased. However, the model results also show that as wall height increased, the deposit surface area from which heat energy is lost via convection and radiation increased. The model also demonstrated that the use of a means of forced convection to rapidly remove heat from the deposit could be an effective way to boost

  11. An Investigation of the Additive Benefits of Parent Dialogic Reading Techniques in Older Preschool Children

    ERIC Educational Resources Information Center

    Switalski, Sarah O'Neill

    2012-01-01

    This study examined the additive benefit of parent dialogic reading techniques in older, high-risk preschool children using multiple baseline design across participants, a single subject research design, as was as well as pre-test and post-test measures. Five preschoolers age-eligible to begin kindergarten the following school year participated.…

  12. Investigation of mechanical properties of masterbatches and composites with small additions of CNTs

    NASA Astrophysics Data System (ADS)

    Burmistrov, I. N.; Yudintseva, T. I.; Ilinykh, I. A.; Khaydarov, B. B.; Mazov, I. N.; Anshin, S. M.; Kuznetsov, D. V.

    2016-01-01

    The present paper investigated physical and mechanical properties of the nanotube masterbatches and the polymer composites with low contents of carbon nanotubes (CNTs), which were obtained by diluting masterbatches. Ethylene-octene copolymer was used as the binder for the masterbatches, which provides the elasticity of the material at a content 20 wt% of CNT. Masterbatches were obtained with a 2-roller mixer, and their additive to polypropylene was carried out on a single screw injection molding machine. Strength properties of ethylene-octene copolymer increased when additing CNTs in an amount of 5-20 wt%. When the concentration of CNT in masterbatches is reduced to 0.01-0.1 wt% its strength characteristics increased up to 4-18%. The most effective strengthening of polypropylene was observed with the content of CNTs 0.1 wt%.

  13. The influence of additives on beer stability investigated by EPR spectroscopy

    NASA Astrophysics Data System (ADS)

    Brezová, Vlasta; Polovka, Martin; Staško, Andrej

    2002-04-01

    In thermally-accelerated aging followed by EPR spectroscopy of beer samples of various stabilities, free radical 4-hydroxy-2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPOL) was shown to be an effective indicator of the breakdown of a sample's stability, comparable to the commonly used spin trapping agent α-phenyl- N- tert-butylnitrone (PBN). Both indicators were then employed to investigate the influence of additives on beer stability. The addition of L-ascorbic acid (ASC) to the beer samples accelerated the radical processes and a lower stability was found. DL-α-tocopherol (α-TOC) did not influence beer stability significantly (probably due to its limited solubility). Na 2SO 3, described as a very effective stabilizer in experiments with the PBN spin trap, was found not to be effective using the TEMPOL indicator. This is probably due to inhibition in the formation of spin adducts or their degradation by Na 2SO 3.

  14. The influence of additives on beer stability investigated by EPR spectroscopy.

    PubMed

    Brezová, Vlasta; Polovka, Martin; Stasko, Andrej

    2002-04-01

    In thermally-accelerated aging followed by EPR spectroscopy of beer samples of various stabilities, free radical 4-hydroxy-2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPOL) was shown to be an effective indicator of the breakdown of a sample's stability, comparable to the commonly used spin trapping agent alpha-phenyl-N-tert-butylnitrone (PBN). Both indicators were then employed to investigate the influence of additives on beer stability. The addition of L-ascorbic acid (ASC) to the beer samples accelerated the radical processes and a lower stability was found. DL-alpha-tocopherol (alpha-TOC) did not influence beer stability significantly (probably due to its limited solubility). Na2SO3, described as a very effective stabilizer in experiments with the PBN spin trap, was found not to be effective using the TEMPOL indicator. This is probably due to inhibition in the formation of spin adducts or their degradation by Na2SO3. PMID:11993475

  15. An Experimental Investigation of the Influence of the Lubricant Viscosity and Additives on Gear Wear

    NASA Technical Reports Server (NTRS)

    Krantz, Timothy L.; Kahraman, Ahmet

    2005-01-01

    The influence of lubricant viscosity and additives on the average wear rate of spur gear pairs was investigated experimentally. The gear specimens of a comprehensive gear durability test program that made use of seven lubricants covering a range of viscosities were examined to measure gear tooth wear. The measured wear was related to the as-manufactured surface roughness, the elastohydrodynamic film thickness, and the experimentally determined contact fatigue lives of the same specimens. In general, the wear rate was found to be inversely proportional to the viscosity of the lubricant and to the lambda ratio (also sometimes called the specific film thickness). The data also show an exponential trend between the average wear rates and the surface fatigue lives. Lubricants with similar viscosities but differing additives and compositions had somewhat differing gear surface fatigue lives and wear rates.

  16. Investigation of the effects of short chain processing additives on polymers

    NASA Technical Reports Server (NTRS)

    Singh, J. J.; Stclair, T. L.; Pratt, J. R.

    1986-01-01

    The effects of low level concentrations of several short chain processing additives on the properties of the 4,4'-bis(3,4-dicarboxyphenoxy) diphenylsulfide dianhydride (BDSDA)/4,4'-diaminodiphenyl ether (ODA)/1,3'-diaminobenzene (m-phenylene diamine) (MPA) (422) copolyimide were investigated. It was noted that 5 percent MPD/phthalic anhydride (PA) is more effective than 5 percent ODA/PA and BDSDA/aniline (AN) in strengthening the host material. However, the introduction of 10 percent BDSDA/AN produces disproportionately high effects on free volume and free electron density in the host copolyimide.

  17. Investigation of microstructure in additive manufactured Inconel 625 by spatially resolved neutron transmission spectroscopy

    DOE PAGESBeta

    Tremsin, Anton S.; Gao, Yan; Dial, Laura C.; Grazzi, Francesco; Shinohara, Takenao

    2016-07-08

    Non-destructive testing techniques based on neutron imaging and diffraction can provide information on the internal structure of relatively thick metal samples (up to several cm), which are opaque to other conventional non-destructive methods. Spatially resolved neutron transmission spectroscopy is an extension of traditional neutron radiography, where multiple images are acquired simultaneously, each corresponding to a narrow range of energy. The analysis of transmission spectra enables studies of bulk microstructures at the spatial resolution comparable to the detector pixel. In this study we demonstrate the possibility of imaging (with ~100 μm resolution) distribution of some microstructure properties, such as residual strain,more » texture, voids and impurities in Inconel 625 samples manufactured with an additive manufacturing method called direct metal laser melting (DMLM). Although this imaging technique can be implemented only in a few large-scale facilities, it can be a valuable tool for optimization of additive manufacturing techniques and materials and for correlating bulk microstructure properties to manufacturing process parameters. Additionally, the experimental strain distribution can help validate finite element models which many industries use to predict the residual stress distributions in additive manufactured components.« less

  18. Investigation of smart inspection of critical layer reticles using additional designer data to determine defect significance

    NASA Astrophysics Data System (ADS)

    Volk, William W.; Hess, Carl; Ruch, Wayne; Yu, Zongchang; Ma, Weimin; Fisher, Lisa; Vickery, Carl; Ma, Z. Mark

    2003-12-01

    With expected implementation of low k1 lithography on 193nm scanners for 65nm node wafer production, high resolution defect inspection will be needed to insure reticle quality and reticle manufacture process monitoring. Reticle cost and reticle defectivity are both increasing with each shrink to the next node. Simultaneously, system on chip (SoC) designs are increasing in which a large area of the exposure field typically contains dummy patterns and other features which are not electrically active. Knowing which defects will electrically impact device yield and performance can improve reticle manufacturing yield and cycle time -- resulting in lower reticle costs. This investigation examines the feasibility of using additional design data layers for die-to-database reticle inspection to determine in real time the relevance of a reticle defect by its location in the device (Smart InspectionTM). The impact to data preparation and inspection throughput is evaluated. The current prototype algorithm is built on the XPA and XPE die-to-database algorithms for chrome-on-glass and EPSM reticles, respectively. The algorithms implement variable sensitivity based on the additional design data regions. During defect review the defects are intelligently binned into the different predetermined design regions. Tests show the new Smart Inspection algorithm provides the capability of using higher than normal sensitivity in critical regions while reducing sensitivity in less critical regions to filter total defect counts and allow for the review of just defects that matter. Performance characterization of a variable sensitivity Smart Inspection algorithm is discussed in addition to the filtering of the total defect count during review to show the defects that matter to device performance. Using seven critical layer production reticles from a system on chip device we examine the applications of Smart Inspection by layer including active, poly, contact, metal and via layers. Data volume

  19. BIG FROG WILDERNESS STUDY AREA AND ADDITIONS, TENNESSEE AND GEORGIA.

    USGS Publications Warehouse

    Slack, John F.; Gazdik, Gertrude C.

    1984-01-01

    A mineral-resource survey was made of the Big Frog Wilderness Study Area and additions, Tennessee-Georgia. Geochemical sampling found traces of gold, zinc, copper, and arsenic in rocks, stream sediments, and panned concentrates, but not in sufficient quantities to indicate the presence of deposits of these metals. The results of the survey indicate that there is little promise for the occurrence of metallic mineral deposits within the study area. The only apparent resources are nonmetallic commodities including rock suitable for construction materials, and small amounts of sand and gravel; however, these commodities are found in abundance outside the study area. A potential may exist for oil and natural gas at great depths, but this cannot be evaluated by the present study.

  20. Recommended Protocol for Round Robin Studies in Additive Manufacturing

    PubMed Central

    Moylan, Shawn; Brown, Christopher U.; Slotwinski, John

    2016-01-01

    One way to improve confidence and encourage proliferation of additive manufacturing (AM) technologies and parts is by generating more high quality data describing the performance of AM processes and parts. Many in the AM community see round robin studies as a way to generate large data sets while distributing the cost among the participants, thereby reducing the cost to individual users. The National Institute of Standards and Technology (NIST) has conducted and participated in several of these AM round robin studies. While the results of these studies are interesting and informative, many of the lessons learned in conducting these studies concern the logistics and methods of the study and unique issues presented by AM. Existing standards for conducting interlaboratory studies of measurement methods, along with NIST’s experience, form the basis for recommended protocols for conducting AM round robin studies. The role of round robin studies in AM qualification, some of the limitations of round robin studies, and the potential benefit of less formal collaborative experiments where multiple factors, AM machine being only one, are varied simultaneously are also discussed. PMID:27274602

  1. Hydration process of cement in the presence of a cellulosic additive. A calorimetric investigation.

    PubMed

    Ridi, Francesca; Fratini, Emiliano; Mannelli, Francesca; Baglioni, Piero

    2005-08-01

    In the cement industry, the extrusion technique is used to produce flat shapes with improved resistance to compression. Extrusion is a plastic-forming process that consists of forcing a highly viscous plastic mixture through a shaped die. The material should be fluid enough to be mixed and to pass through the die, and on the other hand, the extruded specimen should be stiff enough to be handled without changing in shape or cracking. These characteristics are industrially obtained by adding cellulosic polymers to the mixture. The aim of this work is to understand the action mechanism of these additives on the major pure phases constituting a typical Portland cement: tricalcium silicate (C(3)S), dicalcium silicate (C(2)S), tricalcium aluminate (C(3)A), and tetracalcium iron-aluminate (C(4)AF). In particular, a methylhydroxyethyl cellulose (MHEC) was selected from the best-performing polymers for further study. The effect of this additive on the hydration kinetics (rate constants, activation energies, and diffusional constants) was evaluated by means of differential scanning calorimetry (DSC) while the hydration products were studied by using thermogravimetry-differential thermal analysis (TG-DTA), X-ray diffraction (XRD), and scanning electron microscopy (SEM). MHEC addition in calcium silicate pastes produces an increase in the induction time without affecting the nucleation-and-growth period. A less dense CSH gel was deduced from the diffusional constants in the presence of MHEC. Moreover, CSH laminar features and poorly structured hydrates were noted during the first hours of hydration. In the case of the aluminous phases, the additive inhibits the growth of stable cubic hydrated phases (C(3)AH(6)), with the advantage of the metastable hexagonal phases being formed in the earliest minutes of hydration. PMID:16852857

  2. Atomic investigation of alloying Cr, Ti, Y additions in a grain boundary of vanadium

    NASA Astrophysics Data System (ADS)

    Zhang, Pengbo; Li, Xiaojie; Zhao, Jijun; Zheng, Pengfei; Chen, Jiming

    2016-01-01

    The effect of alloying additions (Cr, Ti and Y) in a vanadium (V) ∑3 (111) grain boundary (GB) is investigated by first-principles calculations. To determine site preference and segregation properties of Cr, Ti and Y in the GB and bulk, we calculate the formation energies and segregation energies for different interstitial and substitutional sites. Cr/Ti/Y atom prefers to segregate to the substitutional sites of the GB from bulk environment, whereas Cr segregation to GB is very weak. Based on the Rice and Wang's model, Cr acts as the GB cohesion, while Ti and Y are strong embrittlers. The analysis of atomic and electronic structures provides a reasonable expansion for the embrittlement behavior. Moreover, the effect of Cr, Ti and Y in the GB on solution of interstitial impurities C, N, O, H, and He are determined. The results show that Cr restrains solution of these impurities in the GB, while Ti tends to form Ti-N complex by absorbing N impurities and Y can absorbs O and He impurities. The present calculations are helpful for understanding the behavior of alloying Cr, Ti, Y additions at the grain boundary of vanadium.

  3. Genotoxicity studies of the food additive ester gum.

    PubMed

    Mukherjee, A; Agarwal, K; Chakrabarti, J

    1992-07-01

    Ester gum (EG) is used in citrus oil-based beverage flavourings as a weighting or colouring agent. In the present study, concentrations of 50, 100 and 150 mg/kg body weight were administered orally to male Swiss albino mice, and sister chromatid exchange and chromosomal aberration were used as the cytogenetic endpoints to determine the genotoxic and clastogenic potential of the food additive. Although EG was weakly clastogenic and could induce a marginal increase in sister chromatid exchange frequencies, it was not a potential health hazard at the doses tested. PMID:1521837

  4. RAMSEYS DRAFT WILDERNESS STUDY AREA AND ADDITION, VIRGINIA.

    USGS Publications Warehouse

    Lesure, Frank G.; Mory, Peter C.

    1984-01-01

    Mineral-resource surveys of the Ramseys Draft Wilderness Study Area and adjoining roadless area addition in George Washington National Forest in the western valley and ridge province, Augusta and Highland Counties, Virginia, were done. The surveys outlined three small areas containing anomalous amounts of copper, lead, and zinc related to stratabound red-bed copper mineralization, but these occurrences are not large and are not considered as having mineral-resource potential. The area contains abundant sandstone suitable for construction materials and shale suitable for making brick, tile, and other low-grade ceramic products, but these commodities occur in abundance outside the wilderness study area. Structural conditions are probably favorable for the accumulation of natural gas, but exploratory drilling has not been done sufficiently near the area to evaluate the gas potential.

  5. Investigations of non-linear polymers as high performance lubricant additives

    SciTech Connect

    Robinson, Joshua W.; Bhattacharya, Priyanka; Qu, Jun; Bays, J. Timothy; Cosimbescu, Lelia

    2015-03-22

    structures including the tailoring of peripheral functional groups, conformational flexibility via lipophilic long chain linkers, and a readily available synthesis amenable to scale-up. In the following communication, the synthesis of an aryl comb-burst hyperbranched polymer will be described. Some of the challenges we had to overcome are being highlighted, such as efforts towards increasing lipophilicity of the molecule via changes in saturated carbon content, controlling polymerization conditions to control average molecular weight and degree of branching. In addition, trends in viscosity modification of the bulk oil and wear/friction studies will be discussed.

  6. Investigation of the impact of additional traffic volumes on existing arterials

    SciTech Connect

    Selman, W.A.

    1986-01-01

    New developments attract a large number of additional vehicular trips to the areas in which they are located. An assessment of the impact of these additional trips on surrounding street systems is often needed. The objective of this study is the development of a regression model that would assess this impact. The model predicts increases in average vehicular delay due to specific increases in traffic volumes. It should be very useful since it requires less data than computerized simulation models, it does not require the use of a computer, and it is expected to give reasonably accurate estimates of delays. To develop the proposed model, traffic flow characteristics on six arterials were simulated. The traffic flow model TRANSYT-7F was used to simulate traffic operations on the arterials for four values of increased volumes. These simulations generated the necessary data for the development of the prediction model. Using existing traffic characteristics as predictors, four regression equations were developed and validated. The equations predict the increase in average delay in seconds per vehicle, corresponding to increases in volume of 200, 300, 500, and 700 vehicles per hour.

  7. Theoretical investigation of the effect of hydrogen addition on the formation and properties of soliton in direct current argon plasma

    SciTech Connect

    Saikia, P. Goswami, K. S.; Saikia, B. K.

    2014-03-15

    In this study the effect of hydrogen addition on the formation and properties of soliton in direct-current (DC) argon plasma is theoretically investigated. By coupling fluid equations with Poisons equation for such multi-component plasma, the Mach number and amplitude of the soliton are determined following pseudo potential method. Addition of hydrogen in argon discharge leads to the decrease of electron, Ar{sup +} ion density while a reverse trend was observed for ArH{sup +} and hydrogen like ions. It was found that presence of hydrogen like ions in argon plasma affects the formation of soliton with its amplitude significantly decreases as concentration of hydrogen increases. On the other hand, increase in ion to electron temperature ratios of the lighter ions in the discharge also has a significant influence on the amplitude and formation of soliton. The inverse relation between solitons width and amplitude is found to be consistent for the entire range of study.

  8. Theoretical investigation of the effect of hydrogen addition on the formation and properties of soliton in direct current argon plasma

    NASA Astrophysics Data System (ADS)

    Saikia, P.; Goswami, K. S.; Saikia, B. K.

    2014-03-01

    In this study the effect of hydrogen addition on the formation and properties of soliton in direct-current (DC) argon plasma is theoretically investigated. By coupling fluid equations with Poisons equation for such multi-component plasma, the Mach number and amplitude of the soliton are determined following pseudo potential method. Addition of hydrogen in argon discharge leads to the decrease of electron, Ar+ ion density while a reverse trend was observed for ArH+ and hydrogen like ions. It was found that presence of hydrogen like ions in argon plasma affects the formation of soliton with its amplitude significantly decreases as concentration of hydrogen increases. On the other hand, increase in ion to electron temperature ratios of the lighter ions in the discharge also has a significant influence on the amplitude and formation of soliton. The inverse relation between solitons width and amplitude is found to be consistent for the entire range of study.

  9. Parasexuality in genitourinary investigations: a qualitative study

    PubMed Central

    2014-01-01

    the participants suppressed their sexuality. Viewing staff as professional was an additional strategy used by participants to limit any sexuality as parasexuality. Conclusion This study has contributed towards the appeal for more studies to examine privacy perceptions of patients in genitalia-related care, however, it is by no means definitive. Parasexuality goes some way to explain the dynamics of communication between older men and health care professionals during genitourinary investigations. PMID:24606673

  10. The cryogenic bonding evaluation at the metallic-composite interface of a composite overwrapped pressure vessel with additional impact investigation

    NASA Astrophysics Data System (ADS)

    Clark, Eric A.

    A bonding evaluation that investigated the cryogenic tensile strength of several different adhesives/resins was performed. The test materials consisted of 606 aluminum test pieces adhered to a wet-wound graphite laminate in order to simulate the bond created at the liner-composite interface of an aluminum-lined composite overwrapped pressure vessel. It was found that for cryogenic applications, a flexible, low modulus resin system must be used. Additionally, the samples prepared with a thin layer of cured resin -- or prebond -- performed significantly better than those without. It was found that it is critical that the prebond surface must have sufficient surface roughness prior to the bonding application. Also, the aluminum test pieces that were prepared using a surface etchant slightly outperformed those that were prepared with a grit blast surface finish and performed significantly better than those that had been scored using sand paper to achieve the desired surface finish. An additional impact investigation studied the post impact tensile strength of composite rings in a cryogenic environment. The composite rings were filament wound with several combinations of graphite and aramid fibers and were prepared with different resin systems. The rings were subjected to varying levels of Charpy impact damage and then pulled to failure in tension. It was found that the addition of elastic aramid fibers with the carbon fibers mitigates the overall impact damage and drastically improves the post-impact strength of the structure in a cryogenic environment.

  11. Additive Manufacturing in Production: A Study Case Applying Technical Requirements

    NASA Astrophysics Data System (ADS)

    Ituarte, Iñigo Flores; Coatanea, Eric; Salmi, Mika; Tuomi, Jukka; Partanen, Jouni

    Additive manufacturing (AM) is expanding the manufacturing capabilities. However, quality of AM produced parts is dependent on a number of machine, geometry and process parameters. The variability of these parameters affects the manufacturing drastically and therefore standardized processes and harmonized methodologies need to be developed to characterize the technology for end use applications and enable the technology for manufacturing. This research proposes a composite methodology integrating Taguchi Design of Experiments, multi-objective optimization and statistical process control, to optimize the manufacturing process and fulfil multiple requirements imposed to an arbitrary geometry. The proposed methodology aims to characterize AM technology depending upon manufacturing process variables as well as to perform a comparative assessment of three AM technologies (Selective Laser Sintering, Laser Stereolithography and Polyjet). Results indicate that only one machine, laser-based Stereolithography, was feasible to fulfil simultaneously macro and micro level geometrical requirements but mechanical properties were not at required level. Future research will study a single AM system at the time to characterize AM machine technical capabilities and stimulate pre-normative initiatives of the technology for end use applications.

  12. Theoretical and experimental investigation of design for multioptical-axis freeform progressive addition lenses

    NASA Astrophysics Data System (ADS)

    Xiang, HuaZhong; Chen, JiaBi; Zhu, TianFen; Wei, YeFei; Fu, DongXiang

    2015-11-01

    A freeform progressive addition lens (PAL) provides a good solution to correct presbyopia and prevent juvenile myopia by distributing pupils' optical powers of distance zone, near zone, and intermediate zone and is more widely adopted in the present optometric study. However, there is still a lack of a single-optical-axis system for the design of a PAL. This paper focuses on the research for an approach for designing a freeform PAL. A multioptical-axis system based on real viewing conditions using the eyes is employed for the representation of the freeform surface. We filled small pupils in the intermediate zone as a progressive corridor and the distance- and near-vision portions were defined as the standard spherical surfaces delimited by quadratic curves. Three freeform PALs with a spherical surface as the front side and a freeform surface as the backside were designed. We demonstrate the fabrication and measurement technologies for the PAL surface using computer numerical control machine tools from Schneider Smart and a Visionix VM-2000 Lens Power Mapper. Surface power and astigmatic values were obtained. Preliminary results showed that the approach for the design and fabrication is helpful to advance the design procedure optimization and mass production of PALs in optometry.

  13. Health studies indicate MTBE is safe gasoline additive

    SciTech Connect

    Anderson, E.V.

    1993-09-01

    Implementation of the oxygenated fuels program by EPA in 39 metropolitan areas, including Fairbanks and Anchorage, Alaska, in the winter of 1992, encountered some unexpected difficulties. Complaints of headaches, dizziness, nausea, and irritated eyes started in Fairbanks, jumped to Anchorage, and popped up in various locations in the lower 48 states. The suspected culprit behind these complaints was the main additive for oxygenation of gasoline is methyl tert-butyl ether (MTBE). A test program, hastily organized in response to these complaints, has indicated that MTBE is a safe gasoline additive. However, official certification of the safety of MTBE is still awaited.

  14. Synthesis of [70]Azafulleriods: Investigations of azide addition to C{sub 70}

    SciTech Connect

    Bellavia-Lund, C.; Wudl, F.

    1997-02-05

    Treatment of C{sub 70} with (2-methoxyethoxy)methyl azide gives rise to three out of a possible six triazoline isomers, showing chemoselectivity as well as regioselectivity. The major product arose from addition of azide to the double bond of C{sub 70} possessing the greatest local curvature. Selective thermolysis of the least stable triazoline, the one resulting from addition to the least curved [6,6] double bond, allowed solution of the structure of the three isomers. Thermolysis of the triazoline isomers produced mixtures of C{sub 70}, azafulleroids, and fulleroaziridines. 14 refs., 1 fig.

  15. 78 FR 12937 - Additional Safeguards for Children in Clinical Investigations of Food and Drug Administration...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-26

    ... burdensome to institutions, IRBs, and the process of clinical investigation (66 FR 20589 at 20591). The... VIII. Federalism IX. References I. Background In the Federal Register of April 24, 2001 (66 FR 20589... interim rule (66 FR 20589), including the Food and Drug Administration Modernization Act of 1997...

  16. Fitting additive hazards models for case-cohort studies: a multiple imputation approach.

    PubMed

    Jung, Jinhyouk; Harel, Ofer; Kang, Sangwook

    2016-07-30

    In this paper, we consider fitting semiparametric additive hazards models for case-cohort studies using a multiple imputation approach. In a case-cohort study, main exposure variables are measured only on some selected subjects, but other covariates are often available for the whole cohort. We consider this as a special case of a missing covariate by design. We propose to employ a popular incomplete data method, multiple imputation, for estimation of the regression parameters in additive hazards models. For imputation models, an imputation modeling procedure based on a rejection sampling is developed. A simple imputation modeling that can naturally be applied to a general missing-at-random situation is also considered and compared with the rejection sampling method via extensive simulation studies. In addition, a misspecification aspect in imputation modeling is investigated. The proposed procedures are illustrated using a cancer data example. Copyright © 2015 John Wiley & Sons, Ltd. PMID:26194861

  17. Additional Treatments Offer Little Benefit for Pancreatic Cancer: Study

    MedlinePlus

    ... of gastroenterology-pancreatology at Beaujon Hospital, in Clichy, France. The study was funded by the pharmaceutical company ... D., department of gastroenterology-pancreatology, Beaujon Hospital, Clichy, France; Deborah Schrag, M.D., M.P.H., chief ...

  18. NMR relaxometry study of plaster mortar with polymer additives

    SciTech Connect

    Jumate, E.; Manea, D.; Moldovan, D.; Fechete, R.

    2013-11-13

    The cement mixed with water forms a plastic paste or slurry which stiffness in time and finally hardens into a resistant stone. The addition of sand aggregates, polymers (Walocel) and/or calcium carbonate will modify dramatically the final mortar mechanic and thermal properties. The hydration processes can be observed using the 1D NMR measurements of transverse T{sub 2} relaxation times distributions analysed by a Laplace inversion algorithm. These distributions were obtained for mortar pasta measured at 2 hours after preparation then at 3, 7 and 28 days after preparation. Multiple components are identified in the T{sub 2} distributions. These can be associated with the proton bounded chemical or physical to the mortar minerals characterized by a short T{sub 2} relaxation time and to water protons in pores with three different pore sizes as observed from SEM images. The evaporation process is faster in the first hours after preparation, while the mortar hydration (bonding of water molecules to mortar minerals) can be still observed after days or months from preparation. Finally, the mechanic resistance was correlated with the transverse T{sub 2} relaxation rates corresponding to the bound water.

  19. On the development and investigation of quaternary Pt-based superalloys with Ni additions

    NASA Astrophysics Data System (ADS)

    Wenderoth, M.; Glatzel, U.; Völkl, R.; Cornish, L. A.; Süss, R.; Vorberg, S.; Fischer, B.

    2005-03-01

    The objective of this work is to mimic the microstructure and strengthening mechanisms of Ni-based superalloys in a new group of high-temperature alloys based on the system Pt-Al. The elements Cr and Ni were chosen as further alloying components. Having a face-centered cubic (fcc) crystal structure with an Ll2-ordered and coherently embedded phase, these new alloys should increase creep and corrosion resistance beyond Ni-based superalloys. After arc melting and heat treatment, the alloys were investigated by means of scanning electron microscopy (SEM) and X-ray diffraction (XRD). In the aged condition, the alloy composition 13 at. pct Al, 3 at. pct Cr, 7 at. pct Ni, and balance Pt showed the most promising microstructure with cubical precipitates, 30 pct precipitate volume fraction, and a lattice misfit of about -0.1 pct at room temperature.

  20. Structural, thermal and magnetic investigations on immiscible Ag-Co nanocrystalline alloy with addition of Mn

    NASA Astrophysics Data System (ADS)

    Mondal, B. N.; Chabri, S.; Sardar, G.; Nath, D. N.; Chattopadhyay, P. P.

    2016-08-01

    50Ag-50Co (at%) and 40Ag-40Co-20Mn (at%) alloys prepared by ball milling up to 50 h and subsequent isothermal annealing at the temperature range of 350-650 °C for 1 h has been investigated systematically. Mn promotes early formation of the nanostructures and solid solutions of the alloys by ball milling. In contrast, annealing at 350 °C of Ag-Co alloy resulted the dissolution of hcp Co. Annealing above 350 °C decomposes the metastable Ag-Co alloy into the polycrystalline and segregated Ag and fcc Co. Enthalpy of mixing of both the alloy has increased with increase in milling time. Both the nanocrystalline alloys prepared by ball milling and annealing have been revealed the ferromagnetic behavior. The most significant improvement of magnetic properties is yielded in as-milled Ag-Co-Mn alloy obtained after annealing at 550 °C for 1 h.

  1. An investigation of functionalized electrolyte using succinonitrile additive for high voltage lithium-ion batteries

    NASA Astrophysics Data System (ADS)

    Chen, Renjie; Liu, Fan; Chen, Yan; Ye, Yusheng; Huang, Yongxin; Wu, Feng; Li, Li

    2016-02-01

    Succinonitrile (SN) has been used as functional additive to improve the thermal stability and broaden the oxidation electrochemical window of commercial electrolyte 1 M LiPF6/EC/DEC (1:1, by volume) for high-voltage LIBs (cathode: Li1.2Ni0.2Mn0.6O2, anode: Li). 1 wt % SN-based electrolyte showed a wide electrochemical oxidation window of 5.4 V vs Li+/Li and excellent thermal stability demonstrated by thermogravimetry (TG) and X-ray photoelectron spectroscopy (XPS), as well as theoretical analysis according to molecular orbital theory. The LNMO (Li1.2Ni0.2Mn0.6O2) battery with 1 wt % SN-based electrolyte showed better cyclability and capacity retention when charged to higher cut-off voltage. The improved battery performance is mainly attributed to the formation of uniform cathode electrolyte interface (CEI) formed by interfacial reactions between the LNMO cathode and electrolyte. The outcome of this work and the continuous research on this subject can generate critical knowledge for designing thermal stability electrolytes for large format lithium-ion batteries.

  2. a Study on the Role of Sintering Additives for Fabrication of sic Ceramic

    NASA Astrophysics Data System (ADS)

    Yoon, Han Ki; Lee, Young Ju; Cho, Ho Jun; Kim, Tae Gyu

    Silicon carbide (SiC) materials have been extensively studied for high temperature components in advanced energy system and advanced gas turbine. The SiC ceramics have been fabricated by a NITE (Nano Infiltration Transient Eutectic Phase) Process, using Nano-SiC powder. The sintering additives used for forming liquid phase under sintering process, used the sintering additives ratios were an Al2O3-Y2O3 system or add SiO2 contents. A major R&D focus for the SiC ceramics is the production to obtain high purity SiC ceramics. In this study, we investigated roles of the sintering additives(Al2O3:Y2O3) to fabrication of the SiC ceramics. The effects of SiO2 contents and density properties of the SiC ceramics were also investigated. To investigate the effects of SiO2, Al2O3/Y2O3 composition were fixed and then SiO2 ratios were changed as several kinds, and to confirm the effects of sintering additives ratios (Al2O3:Y2O3) they were changed between 4:6 and 6:4 in x wt.%.

  3. Investigating a Case of Hidden Misinterpretations of an Additive Word Problem: Structural Substitution

    ERIC Educational Resources Information Center

    Polotskaia, Elena; Savard, Annie; Freiman, Viktor

    2016-01-01

    According to numerous studies (Barrouillet & Camos 2002; Brousseau 1988; Chevallard 1988; Riley et al. 1984; Schubauer-Leoni & Ntamakiliro, "Revue Des Sciences de L'éducation," 20(1): 87-113, 1994; Vergnaud 1982; Xin, "The Journal of Educational Research," 100(6):347-360, 2007), a combination of many factors, including…

  4. Investigating the effect of V2O5 addition on sodium barium borosilicate glasses

    NASA Astrophysics Data System (ADS)

    Halder, Rumu; Sengupta, Pranesh; Sudarsan, V.; Kaushik, C. P.; Dey, G. K.

    2016-05-01

    V2O5 doped sodium barium borosilicate glasses were characterized by photoluminescence spectroscopy and electron probe microanalyzer (EPMA). The glass remains homogeneous for lower concentration of V2O5 but a phase separation is observed when V2O5 doping is increased beyond 5 mol%. Detailed microanalysis reveals that the phase separated glass consists of a phase containing V, Ba and Si and a separate Si rich phase within the glass matrix. The luminescence study demonstrated that at low concentration the vanadium mainly interacts with the structural units of B/Si while at higher concentrations, V-O-V/ V-O- Na+/Ba2+ linkages are formed.

  5. Theoretical investigation on improving the ductility of Rh3V by ternary addition

    NASA Astrophysics Data System (ADS)

    Manjula, M.; Sundareswari, M.; Jayalakshmi, D. S.; Viswanathan, E.

    2015-06-01

    The band structure calculations are performed on the intermetallic compounds Rh3V and Rh3Vx(Al)1-x by Full Potential Linearized Augmented Plane Wave(FP-LAPW) method. Total energies are calculated as a function of volume and fitted to Birch-Murnaughan equation of state to find the lattice parameter and the other ground state properties. The ductility of these compounds has been analyzed using Cauchy's Pressure, Pugh Rule and Poisson's ratio. From this study we observed that Rh3V is brittle while its alloy Rh3V0.875Al0.125 is ductile. Electron density plots are illustrated and compared.

  6. Additional EIPC Study Analysis: Interim Report on High Priority Topics

    SciTech Connect

    Hadley, Stanton W

    2013-11-01

    Between 2010 and 2012 the Eastern Interconnection Planning Collaborative (EIPC) conducted a major long-term resource and transmission study of the Eastern Interconnection (EI). With guidance from a Stakeholder Steering Committee (SSC) that included representatives from the Eastern Interconnection States Planning Council (EISPC) among others, the project was conducted in two phases. Phase 1 involved a long-term capacity expansion analysis that involved creation of eight major futures plus 72 sensitivities. Three scenarios were selected for more extensive transmission- focused evaluation in Phase 2. Five power flow analyses, nine production cost model runs (including six sensitivities), and three capital cost estimations were developed during this second phase. The results from Phase 1 and 2 provided a wealth of data that could be examined further to address energy-related questions. A list of 13 topics was developed for further analysis; this paper discusses the first five.

  7. Investigative study of holographic recording materials development

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The potential of certain cis-trans isomers and doped LiNbO3 for the holographic read/write/erase memory application was investigated. The cis-trans work involved the photochemical investigation of a number of potential materials as well as specific molecular engineering efforts on alpha-methyl stilbene and its derivatives. These efforts resulted in an increase in the change in index of refraction, and thereby, in potential recording utility, of an order of magnitude. The work on LiNbO3 was directed toward a preliminary investigation of the dynamics of the writing process. Several samples and a variety of writing conditions were investigated. An unexpected and as yet unexplained improvement in material behavior with continued recycling was observed. In addition, some effort was devoted to an analysis of the physical conditions under which several current theories of the optical damage process are valid.

  8. Theoretical investigation on improving the ductility of Rh{sub 3}V by ternary addition

    SciTech Connect

    Manjula, M.; Sundareswari, M. Jayalakshmi, D. S.; Viswanathan, E.

    2015-06-24

    The band structure calculations are performed on the intermetallic compounds Rh{sub 3}V and Rh{sub 3}V{sub x}(Al){sub 1-x} by Full Potential Linearized Augmented Plane Wave(FP-LAPW) method. Total energies are calculated as a function of volume and fitted to Birch-Murnaughan equation of state to find the lattice parameter and the other ground state properties. The ductility of these compounds has been analyzed using Cauchy’s Pressure, Pugh Rule and Poisson’s ratio. From this study we observed that Rh{sub 3}V is brittle while its alloy Rh{sub 3}V{sub 0.875}Al{sub 0.125} is ductile. Electron density plots are illustrated and compared.

  9. An Investigation of the SOAR Study Method

    ERIC Educational Resources Information Center

    Jairam, Dharma; Kiewra, Kenneth A.

    2009-01-01

    Students are rarely taught how to study. When study strategy instruction occurs, weak strategies are often advocated or strategies are presented in a hodgepodge leaving students without a systematic study plan. This experiment investigated a systematic study plan called SOAR that includes the components of "S"election, "O"rganization,…

  10. An investigation of FT-Raman spectroscopy for quantification of additives to milk

    NASA Astrophysics Data System (ADS)

    Cheng, Yuche; Qin, Jianwei; Lim, Jongguk; Chan, Diane E.; Kim, Moon S.; Chao, Kuanglin

    2012-05-01

    In this research, four chemicals, urea, ammonium sulfate, dicyandiamide, and melamine, were mixed into liquid nonfat milk at concentrations starting from 0.1% to a maximum concentration determined for each chemical according to its maximum solubility, and two Raman spectrometers-a commercial Nicolet Raman system and an in-house Raman Chemical Imaging (RCI) system-were used to acquire Raman shift spectra for these mixture samples. These chemicals are potential adulterants that could be used to artificially elevate protein measurements of milk products evaluated by the Kjeldahl method. Baseline subtraction was employed to eliminate milk intensity, and the normalized Raman intensity was calculated from the specific Raman shift from the spectrum of solid chemical. Linear relationships were found to exist between the normalized Raman intensity and chemical concentrations. The linear regression coefficients (R2) ranged from 0.9111 to 0.998. Although slightly higher R2 values were calculated for regressions using spectral intensities measured by the Nicolet system compared to those using measurements from the RCI system, the results from the two systems were similar and comparable. A very low concentration of melamine (400 ppm) in milk was also found to be detectable by both systems. Raman sensitivity of Nicolet Raman system was estimated from normalized Raman intensity and slope of regression line in this study. Chemicals (0.2%) were dissolved in milk and detected the normalized Raman intensity. Melamine was found to have the highest Raman sensitivity, with the highest values for normalized Raman intensity (0.09) and regression line slope (57.04).

  11. Influence of Polarization on Carbohydrate Hydration: A Comparative Study Using Additive and Polarizable Force Fields.

    PubMed

    Pandey, Poonam; Mallajosyula, Sairam S

    2016-07-14

    Carbohydrates are known to closely modulate their surrounding solvent structures and influence solvation dynamics. Spectroscopic investigations studying far-IR regions (below 1000 cm(-1)) have observed spectral shifts in the libration band (around 600 cm(-1)) of water in the presence of monosaccharides and polysaccharides. In this paper, we use molecular dynamics simulations to gain atomistic insight into carbohydrate-water interactions and to specifically highlight the differences between additive (nonpolarizable) and polarizable simulations. A total of six monosaccharide systems, α and β anomers of glucose, galactose, and mannose, were studied using additive and polarizable Chemistry at HARvard Macromolecular Mechanics (CHARMM) carbohydrate force fields. Solvents were modeled using three additive water models TIP3P, TIP4P, and TIP5P in additive simulations and polarizable water model SWM4 in polarizable simulations. The presence of carbohydrate has a significant effect on the microscopic water structure, with the effects being pronounced for proximal water molecules. Notably, disruption of the tetrahedral arrangement of proximal water molecules was observed due to the formation of strong carbohydrate-water hydrogen bonds in both additive and polarizable simulations. However, the inclusion of polarization resulted in significant water-bridge occupancies, improved ordered water structures (tetrahedral order parameter), and longer carbohydrate-water H-bond correlations as compared to those for additive simulations. Additionally, polarizable simulations also allowed the calculation of power spectra from the dipole-dipole autocorrelation function, which corresponds to the IR spectra. From the power spectra, we could identify spectral signatures differentiating the proximal and bulk water structures, which could not be captured from additive simulations. PMID:27266974

  12. Influence of Ar addition on ozone generation in a non-thermal plasma—a numerical investigation

    NASA Astrophysics Data System (ADS)

    Chen, Hsin Liang; Lee, How Ming; Chen, Shiaw Huei; Wei, Ta Chin; Been Chang, Moo

    2010-10-01

    A numerical model based on a dielectric barrier discharge is developed in this study to investigate the influence of Ar addition on ozone generation. The simulation results show good agreement with the experimental data, confirming the validity of the numerical model. The mechanisms regarding how the Ar addition affects ozone generation are investigated with the assistance of a numerical simulation by probing into the following two questions, (1) why the ozone concentration just slightly decreases in the low specific input energy (SIE, the ratio of discharge power to gas flow rate) region even if the inlet O2 concentration is substantially decreased and (2) why the variation of the increased rate of ozone concentration with SIE (i.e. the variation in the slope of ozone concentration versus SIE) is more significant for an O2/Ar mixture plasma. As SIE is relatively low, ozone decomposition through electron-impact and radical attack reactions is less significant because of low ozone concentration and gas temperature. Therefore, the ozone concentration depends mainly on the amount of oxygen atoms generated. The simulation results indicate that the amount of oxygen atoms generated per electronvolt for Ar concentrations of 0%, 10%, 30%, 50% and 80% are 0.178, 0.174, 0.169, 0.165 and 0.166, respectively, explaining why the ozone concentration does not decrease linearly with the inlet O2 concentration in the low SIE region. On the other hand, the simulation results show that increasing Ar concentration would lead to a lower reduced field and a higher gas temperature. The former would lead to an increase in the rate constant of e + O3 → e + O + O2 while the latter would result in a decrease in the rate constant of O + O2 + M → O3 + M and an increase in that of O3 + O → 2O2. The changes in the rate constants of these reactions would have a negative effect on ozone generation, which is the rationale for the second question.

  13. Fee structure for investigational drug studies.

    PubMed

    Anandan, J V; Isopi, M J; Warren, A J

    1993-11-01

    The development and implementation of a fee structure for a pharmacy-coordinated investigational drug service is described. A pilot task and time study established specific time and cost elements for investigational drug services provided by the pharmacy department. To fully assess the costs in dispensing investigational drugs, each research study that used the investigational drug service was broken down into five phases of service. Each phase was further categorized by specific tasks or activities, and a time element to perform each activity or task was determined. Since some studies could require more elaborate randomization of patients, more extensive review of protocols, or more individualized dispensing procedures than others, a range of charges was derived: $2800 for standard protocols to $5700 for more complicated studies. An institutional drug therapy newsletter describing the services and costs was distributed to all medical staff members and principal investigators. The development of a fee structure for an investigational drug service coordinated by the pharmacy department has ensured that pharmacy services are adequately reimbursed and has allowed the department to allocate appropriate personnel to provide the services. PMID:8266958

  14. Using epidemiology to regulate food additives: saccharin case-control studies.

    PubMed

    Cordle, F; Miller, S A

    1984-01-01

    The increasing use of nonnutritive sweeteners and the widely publicized 1969 ban on cyclamate led to additional investigations in rodents of the carcinogenic potential of saccharin. Preliminary results of a long-term feeding study indicated formation of bladder tumors in rodents, and collective experimental evidence has demonstrated that high doses of the synthetic sweetener saccharin can cause bladder cancer in rodents. Based on the results of that and other rodent studies indicating an increased risk of bladder cancer associated with saccharin, the Commissioner of the Food and Drug Administration announced the agency's intention to propose a ban on saccharin. This intention was made known in April 1977 under the Delaney Clause of the Food, Drug, and Cosmetic Act. The clause essentially states that no additive shall be deemed safe if it is found to induce cancer in man or animals, or if it is found, after tests appropriate for the evaluation of the safety of food additives, to induce cancer in man or animals. Also in 1977, a group of epidemiologists began to assess the available epidemiologic information to determine the potential human risk. This report describes the assessment of several human epidemiologic studies available then and the results of more recent epidemiologic studies. PMID:6431484

  15. Theoretical investigation of the addition reaction of the aluminum chlorosilylenoid H2SiAlCl3 with ethylene.

    PubMed

    Zhang, Mingxia; Li, Wenzuo; Liu, Zhenbo; Li, Qingzhong; Cheng, Jianbo

    2016-07-01

    The addition reaction of the aluminum chlorosilylenoid H2SiAlCl3 with ethylene was investigated using the M06-2X and QCISD methods for the first time. The calculated results demonstrate that the addition reaction proceeds via two pathways: path I involves just one transition state, while path II involves two transition states. Path I is more feasible dynamically, as it has a lower barrier height than path II. The effect of the solvent CH2Cl2 was taken into consideration using the PCM model. The results indicated that the addition reaction is less likely to occur in CH2Cl2 solvent than in vacuum. This work has therefore highlighted a new pathway for the synthesis of silicon heterocyclic compounds. Graphical Abstract Relative energies (in kJ·mol(-1)) of the stationary points along the potential energy surfaces of the addition reaction of H2SiAlCl3 with C2H4 (values in parentheses were calculated in CH2Cl2 solvent). PMID:27271163

  16. Investigating critical effects of variegated lubricants, glidants and hydrophilic additives on lag time of press coated ethylcellulose tablets.

    PubMed

    Patadia, Riddhish; Vora, Chintan; Mittal, Karan; Mashru, Rajashree

    2016-01-01

    The research envisaged focuses on vital impacts of variegated lubricants, glidants and hydrophilic additives on lag time of press coated ethylcellulose (EC) tablets using prednisone as a model drug. Several lubricants and glidants such as magnesium stearate, colloidal SiO2, sodium stearyl fumarate, talc, stearic acid, polyethylene glycol (6000) and glyceryl behenate were investigated to understand their effects on lag time by changing their concentrations in outer coat. Further, the effects of hydrophilic additives on lag time were examined for hydroxypropylmethylcellulose (E5), hydroxypropylcellulose (EF and SSL), povidone (K30), copovidone, polyethylene glycol (4000), lactose and mannitol. In vitro drug release testing revealed that each selected lubricant/glidant, if present even at concentration of 0.25% w/w, significantly reduced the lag time of press coated tablets. Specifically, colloidal SiO2 and/or magnesium stearate were detrimental while other lubricants/glidants were relatively less injurious. Among hydrophilic additives, freely water soluble fillers had utmost influence in lag time, whereas, comparatively less impact was observed with polymeric binders. Concisely, glidant and lubricant should be chosen to have minimal impact on lag time and further judicious selection of hydrophilic additives should be exercised for modulating lag time of pulsatile release formulations. PMID:25566928

  17. Experimental investigations of the swirling flow in the conical diffuser using flow-feedback control technique with additional energy source

    NASA Astrophysics Data System (ADS)

    Tǎnasǎ, C.; Bosioc, A. I.; Susan-Resiga, R. F.; Muntean, S.

    2012-11-01

    The previous experimental and numerical investigations of decelerated swirling flows in conical diffusers have demonstrated that water injection along to the axis mitigates the pressure fluctuations associated to the precessing vortex rope [1]. However, for swirling flows similar to Francis turbines operated at partial discharge, the water jet becomes effective when the jet discharge is larger than 10% from the turbine discharge, leading to large volumetric losses when the jet is supplied from upstream the runner. As a result, it was introduced a new approach for supplying the jet by using a fraction of the discharge collected downstream the conical diffuser [2]. This is called flow-feedback control technique (FFCT) and it was investigated experimentally in order to assess its capability [3]. The FFCT approach not requires additional energy to supply the jet. Consequently, the turbine efficiency is not diminished due to the volumetric losses injected even if around 10% of the main flow is used. However, the equivalent amplitude of the pressure pulsations associated to the vortex rope decreases with 30% if 10% jet discharge is applied [3]. Using 12% water jet discharge from upstream then the equivalent amplitude of the pressure pulsations is mitigated with 70% according to Bosioc et al. [4]. In our case, an extra 2% jet discharge is required in order to obtain similar results with FFCT. This extra discharge is provided using an additional energy source. Therefore, the paper presents experimental investigation performed with FFCT with additional energy source. The experimental results obtained with this technique are compared against FFCT and the swirling flow with vortex rope, respectively.

  18. Investigation of SO2, HCl and NOx, control from waste incinerators using a novel additive in a pilot scale reactor.

    PubMed

    Williams, P T; Nimmo, W; Patsias, A; Hall, W

    2006-05-01

    A pilot scale experimental investigation of the use of a novel additive, calcium magnesium acetate, for the simultaneous control of SO2, HCl and NOx has been carried out. The pilot scale reactor simulated the furnace and flue gas conditions of a typical large scale waste incinerator and was a vertical 4m high reactor operated at 80 kW. The calcium magnesium acetate was added as a wet spray to the reactor at temperatures above 750 degrees C. The influence of the calcium magnesium acetate dose rate was investigated on the simultaneous removal of SO2, HCl and NOx. Maximum reductions were achieved at a Ca/S ratio (or Ca/Cl ratio) of 2.5 and were, 70% for SO2, 45% for HCl and 18% for NOx for each of the pollutant gases respectively. PMID:16749624

  19. Nuclear forensic investigations: two case studies.

    PubMed

    Wallenius, M; Mayer, K; Ray, I

    2006-01-01

    This paper describes the methodology and analytical methods used in nuclear forensic investigations. Two case studies are taken as examples to illustrate this. These examples represent typical cases that have been analysed at the Institute for Transuranium Elements (ITU) since last 10 years, i.e. the beginning of the illicit trafficking of nuclear materials. Results of the various analytical techniques are shown, which, together with other type of information, reveal the origin of the material. PMID:16410154

  20. Routine Storage of Red Blood Cell Units in Additive Solution-3: a comprehensive investigation of the RBC metabolome

    PubMed Central

    D'Alessandro, Angelo; Nemkov, Travis; Kelher, Marguerite; West, Bernadette F.; Schwindt, Rani K.; Banerjee, Anirban; Moore, Ernest E; Silliman, Christopher C.; Hansen, Kirk C.

    2014-01-01

    Background In most countries, packed red blood cells (RBCs) can be stored up to 42 days before transfusion. However, observational studies have suggested that storage duration might be associated with increased morbidity and mortality. While clinical trials are underway, impaired metabolism has been documented in RBCs stored in several additive solutions. Here we hypothesize that, despite reported beneficial effects, storage in additive solution-3 (AS-3) results in metabolic impairment weeks before the end of the unit shelf-life. Study design and Methods Five leukocyte-filtered AS-3 RBC units were sampled before, during and after leukoreduction at day0, and then assayed on a weekly basis from storage day1 through day42. RBC extracts and supernatants were assayed using a UHPLC-MS metabolomics workflow. Results Blood bank storage significantly affects metabolic profiles of RBC extracts and supernatants by day14. In addition to energy and redox metabolism impairment, intra- and extracellular accumulation of amino acids was observed proportionally to storage duration, suggesting a role for glutamine and serine metabolism in aging RBCs. Conclusion Metabolomics of stored RBCs could drive the introduction of alternative additive solutions to address some of the storage-dependent metabolic lesions herein reported, thereby increasing the quality of transfused RBCs and minimizing potential links to patient morbidity. PMID:25556331

  1. The ten-ecosystem study investigation plan

    NASA Technical Reports Server (NTRS)

    Kan, E. P.

    1976-01-01

    With the continental United States divided into ten forest and grassland ecosystems, the Ten Ecosystem Study (TES) is designed to investigate the feasibility and applicability of state-of-the-art automatic data processing remote sensing technology to inventory forest, grassland, and water resources by using Land Satellite data. The study will serve as a prelude to a possible future nationwide remote sensing application to inventory forest and rangeland renewable resources. This plan describes project design and phases, the ten ecosystem, data utilization and output, personnel organization, resource requirements, and schedules and milestones.

  2. The guanidine and maleic acid (1:1) complex. The additional theoretical and experimental studies

    NASA Astrophysics Data System (ADS)

    Drozd, Marek; Dudzic, Damian

    2012-04-01

    On the basis of experimental literature data the theoretical studies for guanidinium and maleic acid complex with using DFT method are performed. In these studies the experimental X-ray data for two different forms of investigated crystal were used. During the geometry optimization process one equilibrium structure was found, only. According to this result the infrared spectrum for one theoretical molecule was calculated. On the basis of potential energy distribution (PED) analysis the clear-cut assignments of observed bands were performed. For the calculated molecule with energy minimum the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) were obtained and graphically illustrated. The energy difference (GAP) between HOMO and LUMO was analyzed. Additionally, the nonlinear properties of this molecule were calculated. The α and β (first and second order) hyperpolarizability values are obtained. On the basis of these results the title crystal was classified as new second order NLO generator.

  3. Investigation of the causes for the occurrence of residues of the anticoccidial feed additive nicarbazin in commercial poultry.

    PubMed

    O'Keeffe, M; Capurro, E; Danaher, M; Campbell, K; Elliott, C T

    2007-09-01

    Investigations were undertaken to identify causes for the occurrence of high levels of the zootechnical feed additive nicarbazin in broiler liver at slaughter. The first investigation on 32 commercial broiler flocks involved sampling and analysis for nicarbazin (as dinitrocarbanilide, DNC) in liver from birds during a 3-10-day period after withdrawal of nicarbazin from their feed and before commercial slaughter. DNC residues in liver samples of broilers scheduled as being withdrawn from nicarbazin for > or =6 days ranged from 20 to >1600 microg kg(-1) (the specified withdrawal period for nicarbazin is 5 days and the Joint Expert Committee on Food Additives (JECFA) maximum residue limit (MRL) is 200 microg kg(-1) liver). Further on-farm investigations on 12 of these flocks, selected on the basis of the feeding system in use and the levels of DNC residues determined in liver, identified issues in feed management contributing to elevated residues in broiler liver. A significant correlation (0.81, p < 0.01, n = 10) between DNC residues in liver samples and in feed samples from the feeding pans was observed. The second investigation on 12 commercial broiler flocks involved sampling and analysis for DNC in liver samples and feed samples from feeding pans and from the feed mill at the three thinnings of birds for commercial slaughter. In the case of one flock, a clear relationship between nicarbazin in feed from the feed mill (10.5 mg kg(-1) DNC), in feed from the feeding pans (6.6 mg kg(-1) DNC) and in liver (583 microg kg(-1) DNC) at first thinning (9 days scheduled withdrawal from nicarbazin) was observed. Such a clear relationship was not observed in other cases, particularly at second and third thinnings, pointing to re-exposure of birds to nicarbazin late in the flock production cycle, probably from the litter. Guidelines outlining best farm practice to eliminate nicarbazin residues in poultry have been published in booklet and poster format for broiler producers

  4. Investigation on the Clogging Behavior and Additional Wall Cooling for the Axial-Injection Cold Spray Nozzle

    NASA Astrophysics Data System (ADS)

    Wang, Xudong; Zhang, Bo; Lv, Jinsheng; Yin, Shuo

    2015-04-01

    During the cold spray process, nozzle clogging always happens when spraying low-melting point materials, e.g., aluminum, significantly decreasing the working efficiency. In this paper, a comprehensive investigation was carried out to clarify the reason for inducing nozzle clogging and then to evaluate a home-made nozzle cooling device for preventing nozzle clogging. Computational fluid dynamics technique was employed as the main method with some necessary experiment validation. It is found that the particle dispersion and the high-temperature nozzle wall at the near-throat region are two dominant factors that cause nozzle clogging. The numerical results also reveal that the home-made cooling device can significantly reduce the nozzle wall temperature, which was validated by the experimental measurement. Besides, the aluminum coating build-up experiment further indicates that the additional cooling device can truly prevent the nozzle clogging.

  5. Investigation of Cross-Linked and Additive Containing Polymer Materials for Membranes with Improved Performance in Pervaporation and Gas Separation

    PubMed Central

    Hunger, Katharina; Schmeling, Nadine; Jeazet, Harold B. Tanh; Janiak, Christoph; Staudt, Claudia; Kleinermanns, Karl

    2012-01-01

    Pervaporation and gas separation performances of polymer membranes can be improved by crosslinking or addition of metal-organic frameworks (MOFs). Crosslinked copolyimide membranes show higher plasticization resistance and no significant loss in selectivity compared to non-crosslinked membranes when exposed to mixtures of CO2/CH4 or toluene/cyclohexane. Covalently crosslinked membranes reveal better separation performances than ionically crosslinked systems. Covalent interlacing with 3-hydroxypropyldimethylmaleimide as photocrosslinker can be investigated in situ in solution as well as in films, using transient UV/Vis and FTIR spectroscopy. The photocrosslinking yield can be determined from the FTIR-spectra. It is restricted by the stiffness of the copolyimide backbone, which inhibits the photoreaction due to spatial separation of the crosslinker side chains. Mixed-matrix membranes (MMMs) with MOFs as additives (fillers) have increased permeabilities and often also selectivities compared to the pure polymer. Incorporation of MOFs into polysulfone and Matrimid® polymers for MMMs gives defect-free membranes with performances similar to the best polymer membranes for gas mixtures, such as O2/N2 H2/CH4, CO2/CH4, H2/CO2, CH4/N2 and CO2/N2 (preferentially permeating gas is named first). The MOF porosity, its particle size and content in the MMM are factors to influence the permeability and the separation performance of the membranes. PMID:24958427

  6. Augmenting a Waste Glass Mixture Experiment Study with Additional Glass Components and Experimental Runs

    SciTech Connect

    Piepel, Gregory F. ); Cooley, Scott K. ); Peeler, David K.; Vienna, John D. ); Edwards, Tommy B.

    2002-01-01

    A glass composition variation study (CVS) for high-level waste (HLW) stored in Idaho is being statistically designed and performed in phases over several years. The purpose of the CVS is to investigate and model how HLW-glass properties depend on glass composition. The resulting glass property-composition models will be used to develop desirable glass formulations and for other purposes. Phases 1 and 2 of the CVS have been completed and are briefly described. This paper focuses on the CVS Phase 3 experimental design, which was chosen to augment the Phase 1 and 2 data with additional data points, as well as to account for additional glass components not studied in Phases 1 and/or 2. In total, 16 glass components were varied in the Phase 3 experimental design. The paper describes how these Phase 3 experimental design augmentation challenges were addressed using the previous data, preliminary property-composition models, and statistical mixture experiment and optimal experimental design methods and software.

  7. Neuroscience Investigations: An Overview of Studies Conducted

    NASA Technical Reports Server (NTRS)

    Reschke, Millard F.

    1999-01-01

    The neural processes that mediate human spatial orientation and adaptive changes occurring in response to the sensory rearrangement encountered during orbital flight are primarily studied through second and third order responses. In the Extended Duration Orbiter Medical Project (EDOMP) neuroscience investigations, the following were measured: (1) eye movements during acquisition of either static or moving visual targets, (2) postural and locomotor responses provoked by unexpected movement of the support surface, changes in the interaction of visual, proprioceptive, and vestibular information, changes in the major postural muscles via descending pathways, or changes in locomotor pathways, and (3) verbal reports of perceived self-orientation and self-motion which enhance and complement conclusions drawn from the analysis of oculomotor, postural, and locomotor responses. In spaceflight operations, spatial orientation can be defined as situational awareness, where crew member perception of attitude, position, or motion of the spacecraft or other objects in three-dimensional space, including orientation of one's own body, is congruent with actual physical events. Perception of spatial orientation is determined by integrating information from several sensory modalities. This involves higher levels of processing within the central nervous system that control eye movements, locomotion, and stable posture. Spaceflight operational problems occur when responses to the incorrectly perceived spatial orientation are compensatory in nature. Neuroscience investigations were conducted in conjunction with U. S. Space Shuttle flights to evaluate possible changes in the ability of an astronaut to land the Shuttle or effectively perform an emergency post-landing egress following microgravity adaptation during space flights of variable length. While the results of various sensory motor and spatial orientation tests could have an impact on future space flights, our knowledge of

  8. Spectroscopic studies of nucleic acid additions during seed-mediated growth of gold nanoparticles

    PubMed Central

    Tapp, Maeling; Sullivan, Rick; Dennis, Patrick; Naik, Rajesh R.

    2015-01-01

    The effect of adding nucleic acids to gold seeds during the growth stage of either nanospheres or nanorods was investigated using UV-Vis spectroscopy to reveal any oligonucleotide base or structure-specific effects on nanoparticle growth kinetics or plasmonic signatures. Spectral data indicate that the presence of DNA duplexes during seed ageing drastically accelerated nanosphere growth while the addition of single-stranded polyadenine at any point during seed ageing induces nanosphere aggregation. For seeds added to a gold nanorod growth solution, single-stranded polythymine induces a modest blue-shift in the longitudinal peak wavelength. Moreover, a particular sequence comprised of 50% thymine bases was found to induce a faster, more dramatic blue-shift in the longitudinal peak wavelength compared to any of the homopolymer incubation cases. Monomeric forms of the nucleic acids, however, do not yield discernable spectral differences in any of the gold suspensions studied. PMID:25960601

  9. Summary of Previous Chamber or Controlled Anthrax Studies and Recommendations for Possible Additional Studies

    SciTech Connect

    Piepel, Gregory F.; Amidan, Brett G.; Morrow, Jayne B.

    2010-12-29

    This report and an associated Excel file(a) summarizes the investigations and results of previous chamber and controlled studies(b) to characterize the performance of methods for collecting, storing and/or transporting, extracting, and analyzing samples from surfaces contaminated by Bacillus anthracis (BA) or related simulants. This report and the Excel are the joint work of the Pacific Northwest National Laboratory (PNNL) and the National Institute of Standards and Technology (NIST) for the Department of Homeland Security, Science and Technology Directorate. The report was originally released as PNNL-SA-69338, Rev. 0 in November 2009 with limited distribution, but was subsequently cleared for release with unlimited distribution in this Rev. 1. Only minor changes were made to Rev. 0 to yield Rev. 1. A more substantial update (including summarizing data from other studies and more condensed summary tables of data) is underway

  10. Investigation of the HA film deposited on the porous Ti6Al4V alloy prepared via additive manufacturing

    NASA Astrophysics Data System (ADS)

    Surmeneva, M.; Chudinova, E.; Syrtanov, M.; Koptioug, A.; Surmenev, R.

    2015-11-01

    This study is focused on the use of radio frequency magnetron sputtering to modify the surface of porous Ti6Al4V alloy fabricated via additive manufacturing technology. The hydroxyapatite (HA) coated porous Ti6Al4V alloy was studied in respect with its chemical and phase composition, surface morphology, water contact angle and hysteresis, and surface free energy. Thin nanocrystalline HA film was deposited while its structure with diamond-shaped cells remained unchanged. Hysteresis and water contact angle measurements revealed an effect of the deposited HA films, namely an increased water contact angle and contact angle hysteresis. The increase of the contact angle of the coating-substrate system compared to the uncoated substrate was attributed to the multiscale structure of the resulted surfaces.

  11. A combined toxicity study of zinc oxide nanoparticles and vitamin C in food additives

    NASA Astrophysics Data System (ADS)

    Wang, Yanli; Yuan, Lulu; Yao, Chenjie; Ding, Lin; Li, Chenchen; Fang, Jie; Sui, Keke; Liu, Yuanfang; Wu, Minghong

    2014-11-01

    At present, safety evaluation standards for nanofood additives are made based on the toxic effects of a single additive. Since the size, surface properties and chemical nature influence the toxicity of nanomaterials, the toxicity may have dramatically changed when nanomaterials are used as food additives in a complex system. Herein, we investigated the combined toxicity of zinc oxide nanoparticles (ZnO NPs) and vitamin C (Vc, ascorbic acid). The results showed that Vc increased the cytotoxicity significantly compared with that of the ZnO only NPs. When the cells were exposed to ZnO NPs at a concentration less than 15 mg L-1, or to Vc at a concentration less than 300 mg L-1, there was no significant cytotoxicity, both in the case of gastric epithelial cell line (GES-1) and neural stem cells (NSCs). However, when 15 mg L-1 of ZnO NPs and 300 mg L-1 of Vc were introduced to cells together, the cell viability decreased sharply indicating significant cytotoxicity. Moreover, the significant increase in toxicity was also shown in the in vivo experiments. The dose of the ZnO NPs and Vc used in the in vivo study was calculated according to the state of food and nutrition enhancer standard. After repeated oral exposure to ZnO NPs plus Vc, the injury of the liver and kidneys in mice has been indicated by the change of these indices. These findings demonstrate that the synergistic toxicity presented in a complex system is essential for the toxicological evaluation and safety assessment of nanofood.At present, safety evaluation standards for nanofood additives are made based on the toxic effects of a single additive. Since the size, surface properties and chemical nature influence the toxicity of nanomaterials, the toxicity may have dramatically changed when nanomaterials are used as food additives in a complex system. Herein, we investigated the combined toxicity of zinc oxide nanoparticles (ZnO NPs) and vitamin C (Vc, ascorbic acid). The results showed that Vc increased the

  12. Theoretical investigation on mechanism of asymmetric Michael addition of malononitrile to chalcones catalyzed by Cinchona alkaloid aluminium(III) complex.

    PubMed

    Su, Zhishan; Lee, Hai Whang; Kim, Chan Kyung

    2011-09-21

    The mechanism of Michael addition of malononitrile to chalcones catalyzed by Cinchona alkaloid aluminium(III) complex has been investigated by DFT and ONIOM methods. Calculations indicate that the reaction proceeds through a dual activation mechanism, in which Al(III) acts as a Lewis acid to activate the electrophile α,β-unsaturated carbonyl substrate while the tertiary amine in the Cinchona alkaloid works as a Lewis base to promote the activation of the malononitrile and deprotonation. A stepwise pathway involving C-C bond formation followed by proton transfer from the catalyst to the carbonyl substrate is adopted, and latter step is predicted to be the rate-determining-step in the reaction with an energy barrier of 12.4 kcal mol(-1). In the absence of the Al(III)-complex, a Cinchona alkaloid activates the carbonyl substrate by a hydrogen bonding of the hydroxyl group, involving a higher energy barrier of 30.4 kcal mol(-1). The steric repulsion between the phenyl group attached to the carbonyl group in the chalcone and isopropoxyl groups of the Al(III)-complex may play an important role in the control of stereoselectivity. The π-π stacking effect between the quinuclidine ring of the quinine and the phenyl group of the chalcones may also help the stabilization of the preferred molecular complex. These results are in agreement with experimental observations. PMID:21796318

  13. Investigation of thermal, mechanical and magnetic behaviors of the Cu-11%Al alloy with Ag and Mn additions

    SciTech Connect

    Silva, R.A.G.; Paganotti, A.; Gama, S.; Adorno, A.T.; Carvalho, T.M.; Santos, C.M.A.

    2013-01-15

    The investigation of thermal, mechanical and magnetic behaviors of the Cu-11%Al, Cu-11%Al-3%Ag, Cu-11%Al-10%Mn and Cu-11%Al-10%Mn-3%Ag alloys was made using microhardness measurements, differential scanning calorimetry, X-ray diffractometry, scanning electron microscopy, energy dispersion X-ray spectroscopy and magnetic moment change with applied field measurement. The results indicated that the Mn addition changes the phase stability range, the microhardness values and makes undetectable the eutectoid reaction in annealed Cu-11%Al and Cu-11%Al-3%Ag alloys while the presence of Ag does not modify the phase transformation sequence neither microhardness values of the annealed Cu-11%Al and Cu-11%Al-10%Mn alloys, but it increases the magnetic moment of this latter at about 2.7 times and decreases the rates of eutectoid and peritectoid reactions of the former. - Highlights: Black-Right-Pointing-Pointer The microstructure of Cu-Al alloy is modified in the Ag presence. Black-Right-Pointing-Pointer ({alpha} + {gamma}) phase is stabilized down to room temperature when Ag is added to Cu-Al alloy. Black-Right-Pointing-Pointer Ag-rich phase modifies the magnetic characteristics of Cu-Al-Mn alloy.

  14. Additional follow-up telephone counselling and initial smoking relapse: a longitudinal, controlled study

    PubMed Central

    Wu, Lei; He, Yao; Jiang, Bin; Zuo, Fang; Liu, Qinghui; Zhang, Li; Zhou, Changxi

    2016-01-01

    Objectives Smoking cessation services can help smokers to quit; however, many smoking relapse cases occur over time. Initial relapse prevention should play an important role in achieving the goal of long-term smoking cessation. Several studies have focused on the effect of extended telephone support in relapse prevention, but the conclusions remain conflicting. Design and setting From October 2008 to August 2013, a longitudinal, controlled study was performed in a large general hospital of Beijing. Participants The smokers who sought treatment at our smoking cessation clinic were non-randomised and divided into 2 groups: face-to-face individual counselling group (FC group), and face-to-face individual counselling plus telephone follow-up counselling group (FCF group). No pharmacotherapy was offered. Outcomes The timing of initial smoking relapse was compared between FC and FCF groups. Predictors of initial relapse were investigated during the first 180 days, using the Cox proportional hazards model. Results Of 547 eligible male smokers who volunteered to participate, 457 participants (117 in FC group and 340 in FCF group) achieved at least 24 h abstinence. The majority of the lapse episodes occurred during the first 2 weeks after the quit date. Smokers who did not receive the follow-up telephone counselling (FC group) tended to relapse to smoking earlier than those smokers who received the additional follow-up telephone counselling (FCF group), and the log-rank test was statistically significant (p=0.003). A Cox regression model showed that, in the FCF group, being married, and having a lower Fagerström test score, normal body mass index and doctor-diagnosed tobacco-related chronic diseases, were significantly independent protective predictors of smoking relapse. Conclusions Within the limitations of this study, it can be concluded that additional follow-up telephone counselling might be an effective strategy in preventing relapse. Further research is still

  15. A review of approaches to the study of turbulence modification by means of non-Newtonian additives

    NASA Astrophysics Data System (ADS)

    Vlassopoulos, Dimitris; Schowalter, William R.

    1987-12-01

    The addition of small amounts of polymers to Newtonian liquids under conditions of turbulent flow results in substantial reduction of skin friction. This phenomenon has been observed experimentally. It can be attributed to the unusual behavior of dilute polymer solutions in turbulent flows. A condensed review of topics relevent to theoretical study of drag reduction by non-Newtonian additives is presented. In addition, the techniques and results of experimental investigations of this phenomenon are examined. It is proposed that dilute solutions of polymers or surfactants can be rheologically characterized by measuring the secondary flow characteristics that occur in the neighborhood of an oscillating cylinder. Plans for conducting these measurements are presented.

  16. Experimental study of combustion characteristics of nanoscale metal and metal oxide additives in biofuel (ethanol)

    PubMed Central

    2011-01-01

    An experimental investigation of the combustion behavior of nano-aluminum (n-Al) and nano-aluminum oxide (n-Al2O3) particles stably suspended in biofuel (ethanol) as a secondary energy carrier was conducted. The heat of combustion (HoC) was studied using a modified static bomb calorimeter system. Combustion element composition and surface morphology were evaluated using a SEM/EDS system. N-Al and n-Al2O3 particles of 50- and 36-nm diameters, respectively, were utilized in this investigation. Combustion experiments were performed with volume fractions of 1, 3, 5, 7, and 10% for n-Al, and 0.5, 1, 3, and 5% for n-Al2O3. The results indicate that the amount of heat released from ethanol combustion increases almost linearly with n-Al concentration. N-Al volume fractions of 1 and 3% did not show enhancement in the average volumetric HoC, but higher volume fractions of 5, 7, and 10% increased the volumetric HoC by 5.82, 8.65, and 15.31%, respectively. N-Al2O3 and heavily passivated n-Al additives did not participate in combustion reactively, and there was no contribution from Al2O3 to the HoC in the tests. A combustion model that utilized Chemical Equilibrium with Applications was conducted as well and was shown to be in good agreement with the experimental results. PMID:21711760

  17. Addition reaction of alkyl radical to C60 fullerene: Density functional theory study

    NASA Astrophysics Data System (ADS)

    Tachikawa, Hiroto; Kawabata, Hiroshi

    2016-02-01

    Functionalized fullerenes are known as a high-performance molecules. In this study, the alkyl-functionalized fullerenes (denoted by R-C60) have been investigated by means of the density functional theory (DFT) method to elucidate the effects of functionalization on the electronic states of fullerene. Also, the reaction mechanism of alkyl radicals with C60 was investigated. The methyl, ethyl, propyl, and butyl radicals (denoted by n = 1-4, where n means the number of carbon atoms in the alkyl radical) were examined as alkyl radicals. The DFT calculation showed that the alkyl radical binds to the carbon atom of C60 at the on-top site, and a strong C-C single bond is formed. The binding energies of alkyl radicals to C60 were distributed in the range of 31.8-35.1 kcal mol-1 at the CAM-B3LYP/6-311G(d,p) level. It was found that the activation barrier exists before alkyl addition, the barrier heights were calculated to be 2.1-2.8 kcal mol-1. The electronic states of R-C60 complexes were discussed on the basis of the theoretical results.

  18. Genetic assessment of additional endophenotypes from the Consortium on the Genetics of Schizophrenia Family Study.

    PubMed

    Greenwood, Tiffany A; Lazzeroni, Laura C; Calkins, Monica E; Freedman, Robert; Green, Michael F; Gur, Raquel E; Gur, Ruben C; Light, Gregory A; Nuechterlein, Keith H; Olincy, Ann; Radant, Allen D; Seidman, Larry J; Siever, Larry J; Silverman, Jeremy M; Stone, William S; Sugar, Catherine A; Swerdlow, Neal R; Tsuang, Debby W; Tsuang, Ming T; Turetsky, Bruce I; Braff, David L

    2016-01-01

    The Consortium on the Genetics of Schizophrenia Family Study (COGS-1) has previously reported our efforts to characterize the genetic architecture of 12 primary endophenotypes for schizophrenia. We now report the characterization of 13 additional measures derived from the same endophenotype test paradigms in the COGS-1 families. Nine of the measures were found to discriminate between schizophrenia patients and controls, were significantly heritable (31 to 62%), and were sufficiently independent of previously assessed endophenotypes, demonstrating utility as additional endophenotypes. Genotyping via a custom array of 1536 SNPs from 94 candidate genes identified associations for CTNNA2, ERBB4, GRID1, GRID2, GRIK3, GRIK4, GRIN2B, NOS1AP, NRG1, and RELN across multiple endophenotypes. An experiment-wide p value of 0.003 suggested that the associations across all SNPs and endophenotypes collectively exceeded chance. Linkage analyses performed using a genome-wide SNP array further identified significant or suggestive linkage for six of the candidate endophenotypes, with several genes of interest located beneath the linkage peaks (e.g., CSMD1, DISC1, DLGAP2, GRIK2, GRIN3A, and SLC6A3). While the partial convergence of the association and linkage likely reflects differences in density of gene coverage provided by the distinct genotyping platforms, it is also likely an indication of the differential contribution of rare and common variants for some genes and methodological differences in detection ability. Still, many of the genes implicated by COGS through endophenotypes have been identified by independent studies of common, rare, and de novo variation in schizophrenia, all converging on a functional genetic network related to glutamatergic neurotransmission that warrants further investigation. PMID:26597662

  19. 7 CFR 1710.253 - Engineering and cost studies-addition of generation capacity.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 11 2013-01-01 2013-01-01 false Engineering and cost studies-addition of generation... TO ELECTRIC LOANS AND GUARANTEES Construction Work Plans and Related Studies § 1710.253 Engineering... engineering and cost studies as specified by RUS. The studies shall cover a period from the beginning of...

  20. 7 CFR 1710.253 - Engineering and cost studies-addition of generation capacity.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 11 2010-01-01 2010-01-01 false Engineering and cost studies-addition of generation... TO ELECTRIC LOANS AND GUARANTEES Construction Work Plans and Related Studies § 1710.253 Engineering... engineering and cost studies as specified by RUS. The studies shall cover a period from the beginning of...

  1. Synthesis, Characterization, Molecular Modeling, and DNA Interaction Studies of Copper Complex Containing Food Additive Carmoisine Dye.

    PubMed

    Shahabadi, Nahid; Akbari, Alireza; Jamshidbeigi, Mina; Khodarahmi, Reza

    2016-06-01

    A copper complex of carmoisine dye; [Cu(carmoisine)2(H2O)2]; was synthesized and characterized by using physico-chemical and spectroscopic methods. The binding of this complex with calf thymus (ct) DNA was investigated by circular dichroism, absorption studies, emission spectroscopy, and viscosity measurements. UV-vis results confirmed that the Cu complex interacted with DNA to form a ground-state complex and the observed binding constant (2× 10(4) M(-1)) is more in keeping with the groove bindings with DNA. Furthermore, the viscosity measurement result showed that the addition of complex causes no significant change on DNA viscosity and it indicated that the intercalation mode is ruled out. The thermodynamic parameters are calculated by van't Hoff equation, which demonstrated that hydrogen bonds and van der Waals interactions played major roles in the reaction. The results of circular dichroism (CD) suggested that the complex can change the conformation of DNA from B-like form toward A-like conformation. The cytotoxicity studies of the carmoisine dye and its copper complex indicated that both of them had anticancer effects on HT-29 (colon cancer) cell line and they may be new candidates for treatment of the colon cancer. PMID:27152751

  2. Density functional theory study of the effects of alloying additions on sulfur adsorption on nickel surfaces

    NASA Astrophysics Data System (ADS)

    Malyi, Oleksandr I.; Chen, Zhong; Kulish, Vadym V.; Bai, Kewu; Wu, Ping

    2013-01-01

    Reactions of hydrogen sulfide (H2S) with Nickel/Ytrria-doped zirconia (Ni/YDZ) anode materials might cause degradation of the performance of solid oxide fuel cells when S containing fuels are used. In this paper, we employ density functional theory to investigate S adsorption on metal (M)-doped and undoped Ni(0 0 1) and Ni(1 1 1) surfaces. Based on the performed calculations, we analyze the effects of 12 alloying additions (Ag, Au, Al, Bi, Cd, Co, Cu, Fe, Sn, Sb, V, and Zn) on the temperature of transition between clean (S atoms do not adsorb on the surfaces) and contaminated (S atoms can adsorb on the surfaces spontaneously) M-doped Ni surfaces for different concentrations of H2S in the fuel. Predicted results are consistent with many experimental studies relevant to S poisoning of both Ni/YDZ and M-doped Ni/YDZ anode materials. This study is important to understand S poisoning phenomena and to develop new S tolerant anode materials.

  3. Fundamental Mechanistic Investigations of Silane and Chlorocarbon Addition to Low Valent Palladium Species and their Application to Catalysis

    SciTech Connect

    Fink, Mark J.

    2009-01-27

    The collaboration between Mark Fink (Tulane University) and R. Morris Bullock (Brookhaven National Laboratory, currently at PNL) is an effort to understand some of the fundamental processes involved in catalytic bond activations with low coordinate palladium species. The project involves the photochemical generation of reactive low-valent palladium species as transients using nanosecond laser flash photolysis and the subsequent investigation of their reactions with chloroarenes and hydrosilanes. In the case of Si-H activation of hydrosilanes, relatively long-lived sigma complexes are implicated. These complexes may be important models for C-H activation in hydrocarbons. The information obtained from these studies will help in the understanding of fundamental processes involved in a number of important catalytic reactions in the petrochemical and environmental areas.

  4. Investigation of helium addition for laser-induced plasma spectroscopy of pure gas phase systems: Analyte interactions and signal enhancement

    NASA Astrophysics Data System (ADS)

    Henry, C. A.; Diwakar, P. K.; Hahn, D. W.

    2007-12-01

    The role of helium addition on the analyte signal enhancement in laser-induced breakdown spectroscopy for analysis of pure gaseous systems was examined using carbon and hydrogen atomic emission lines. Increased analyte response, as measured by peak-to-base and signal-to-noise ratios, was observed with increasing helium addition, with maximum enhancement approaching a factor of 7. Additional measurements revealed a significant decrease in plasma electron density with increasing helium addition. To explore the mechanisms of analyte signal enhancement, the helium emission lines were also examined and found to be effectively quenched with nitrogen addition. In consideration of the data, it is concluded that the role of metastable helium is not as important as the overall changes in plasma properties, namely electron density and laser-plasma coupling. Helium addition is concluded to affect the electron density via Penning ionization, as well as to play a role in the initial plasma breakdown processes.

  5. Electrical resistivity tomography investigations on a paleoseismological trenching study

    NASA Astrophysics Data System (ADS)

    Berge, Meriç Aziz

    2014-10-01

    Two-dimensional electrical resistivity tomography (ERT) investigation was performed in a paleoseismological trenching study. Data acquisition strategies such as the selection of electrode configuration and electrode intervals of ERT application were investigated in this paper. The ERT results showed that the Wenner and Wenner-Schlumberger arrays yielded similar results for subsurface characteristics whereas the DD array provided slightly different results. The combined usage of these arrays produced satisfactory images of the subsurface resistivity distribution. In addition, the electrode spacing tests revealed that a suitable interpretation of subsurface geology can be obtained from a 5 m electrode interval. However, a suitable trenching location defined by successful 2D resistivity models was obtained for 1 m electrode spacing. Therefore, the comparison of the trench and ERT results was also possible. The results of trenching and ERT studies substantially support each other.

  6. Investigation on the eco-toxicity of lake sediments with the addition of drinking water treatment residuals.

    PubMed

    Yuan, Nannan; Wang, Changhui; Pei, Yuansheng

    2016-08-01

    Drinking water treatment residuals (WTRs) have a potential to realize eutrophication control objectives by reducing the internal phosphorus (P) load of lake sediments. Information regarding the ecological risk of dewatered WTR reuse in aquatic environments is generally lacking, however. In this study, we analyzed the eco-toxicity of leachates from sediments with or without dewatered WTRs toward algae Chlorella vulgaris via algal growth inhibition testing with algal cell density, chlorophyll content, malondialdehyde content, antioxidant enzyme superoxide dismutase activity, and subcellular structure indices. The results suggested that leachates from sediments unanimously inhibited algal growth, with or without the addition of different WTR doses (10% or 50% of the sediment in dry weight) at different pH values (8-9), as well as from sediments treated for different durations (10 or 180days). The inhibition was primarily the result of P deficiency in the leachates owing to WTR P adsorption, however, our results suggest that the dewatered WTRs were considered as a favorable potential material for internal P loading control in lake restoration projects, as it shows acceptably low risk toward aquatic plants. PMID:27521931

  7. A direct anatomical study of additional renal arteries in a Colombian mestizo population.

    PubMed

    Saldarriaga, B; Pérez, A F; Ballesteros, L E

    2008-05-01

    Traditional anatomy describes each kidney as receiving irrigation from a single renal artery. However, current literature reports great variability in renal blood supply, the number of renal arteries mentioned being the most frequently found variation. Such variation has great implications when surgery is indicated, such as in renal transplants, uroradiological procedures, renovascular hypertension, renal trauma and hydronephrosis. This article pretends to determine the frequency of additional renal arteries and their morphological expression in Colombian population in a cross-sectional study. A total of 196 of renal blocks were analysed from autopsies carried out in the Bucaramanga Institute of Forensic Medicine, Colombia; these renal blocks were processed by the injection- corrosion technique. The average age of the people being studied was 33.8 +/- 15.6 years; 85.4% of them were male and the rest female. An additional renal artery was found in 22.3% of the whole population and two additional ones were found in 2.6% of the same sample. The additional renal artery was most frequently found on the left side. The additional artery arose from the aorta's lateral aspect (52.4%); these additional arteries usually entered the renal parenchyma through the hilum. No difference was established according to gender. Nearly a third of the Colombian population presents one additional renal artery and about 3% of the same population presents two additional renal arteries. Most of them reached the kidney through its hilar region. PMID:18521812

  8. Additional short-term plutonium urinary excretion data from the 1945-1947 plutonium injection studies

    SciTech Connect

    Moss, W.D.; Gautier, M.A.

    1986-01-01

    The amount of plutonium excreted per day following intravenous injection was shown to be significantly higher than predicted by the Langham power function model. Each of the Los Alamos National Laboratory notebooks used to record the original analytical data was studied for details that could influence the findings. It was discovered there were additional urine excretion data for case HP-3. This report presents the additional data, as well as data on case HP-6. (ACR)

  9. 7 CFR 1710.253 - Engineering and cost studies-addition of generation capacity.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 11 2014-01-01 2014-01-01 false Engineering and cost studies-addition of generation capacity. 1710.253 Section 1710.253 Agriculture Regulations of the Department of Agriculture (Continued... TO ELECTRIC LOANS AND GUARANTEES Construction Work Plans and Related Studies § 1710.253...

  10. Evaluating Drugs and Food Additives for Public Use: A Case Studies Approach.

    ERIC Educational Resources Information Center

    Merritt, Sheridan V.

    1980-01-01

    Described is a case study used in an introductory college biology course that provides a basis for generating debate on an issue concerning the regulation of controversial food additives and prescription drugs. The case study contained within this article deals with drug screening, specifically with information related to thalidomide. (CS)

  11. Computational study of the rate constants and free energies of intramolecular radical addition to substituted anilines

    PubMed Central

    Seddiqzai, Meriam; Dahmen, Tobias; Sure, Rebecca

    2013-01-01

    Summary The intramolecular radical addition to aniline derivatives was investigated by DFT calculations. The computational methods were benchmarked by comparing the calculated values of the rate constant for the 5-exo cyclization of the hexenyl radical with the experimental values. The dispersion-corrected PW6B95-D3 functional provided very good results with deviations for the free activation barrier compared to the experimental values of only about 0.5 kcal mol−1 and was therefore employed in further calculations. Corrections for intramolecular London dispersion and solvation effects in the quantum chemical treatment are essential to obtain consistent and accurate theoretical data. For the investigated radical addition reaction it turned out that the polarity of the molecules is important and that a combination of electrophilic radicals with preferably nucleophilic arenes results in the highest rate constants. This is opposite to the Minisci reaction where the radical acts as nucleophile and the arene as electrophile. The substitution at the N-atom of the aniline is crucial. Methyl substitution leads to slower addition than phenyl substitution. Carbamates as substituents are suitable only when the radical center is not too electrophilic. No correlations between free reaction barriers and energies (ΔG ‡ and ΔG R) are found. Addition reactions leading to indanes or dihydrobenzofurans are too slow to be useful synthetically. PMID:24062821

  12. Computational study of the rate constants and free energies of intramolecular radical addition to substituted anilines.

    PubMed

    Gansäuer, Andreas; Seddiqzai, Meriam; Dahmen, Tobias; Sure, Rebecca; Grimme, Stefan

    2013-01-01

    The intramolecular radical addition to aniline derivatives was investigated by DFT calculations. The computational methods were benchmarked by comparing the calculated values of the rate constant for the 5-exo cyclization of the hexenyl radical with the experimental values. The dispersion-corrected PW6B95-D3 functional provided very good results with deviations for the free activation barrier compared to the experimental values of only about 0.5 kcal mol(-1) and was therefore employed in further calculations. Corrections for intramolecular London dispersion and solvation effects in the quantum chemical treatment are essential to obtain consistent and accurate theoretical data. For the investigated radical addition reaction it turned out that the polarity of the molecules is important and that a combination of electrophilic radicals with preferably nucleophilic arenes results in the highest rate constants. This is opposite to the Minisci reaction where the radical acts as nucleophile and the arene as electrophile. The substitution at the N-atom of the aniline is crucial. Methyl substitution leads to slower addition than phenyl substitution. Carbamates as substituents are suitable only when the radical center is not too electrophilic. No correlations between free reaction barriers and energies (ΔG (‡) and ΔG R) are found. Addition reactions leading to indanes or dihydrobenzofurans are too slow to be useful synthetically. PMID:24062821

  13. Field-scale investigation of enhanced petroleum hydrocarbon biodegradation in the vadose zone combining soil venting as an oxygen source with moisture and nutrient addition. Appendices. Doctoral thesis

    SciTech Connect

    Miller, R.N.

    1990-01-01

    This document contains appendices regarding a reprint on a field scale investigation of enhanced petroleum hydrocarbon biodegradation in the vadose zone combining soil venting as a oxygen source with moisture and nutrient addition.

  14. Maltreated children's representations of mother and an additional caregiver: a longitudinal study.

    PubMed

    Manashko, Shany; Besser, Avi; Priel, Beatriz

    2009-04-01

    In the current longitudinal investigation, we explored the continuity of and changes in the mental representations of the mother and an additional caregiver among forty-five 9- to 11-year-old children who had been severely maltreated and subsequently placed in long-term residential care as well as the relationships between the content and structure of these representations and teacher's assessments of the child's externalizing and internalizing symptoms. At Time 1, a nonmaltreated comparison group was assessed concomitantly. Compared to nonmaltreated children, maltreated children scored higher for externalizing and internalizing symptoms, and their maternal representations were found to be significantly less benevolent and integrated and more punitive. In addition, among the maltreated children, the additional caregiver representations were found to be more benevolent and integrated, and less punitive, than the maternal representations. After 30 months, the maltreated children's levels of externalizing and internalizing symptoms diminished, their maternal representations become more benevolent and less punitive, and the additional caregiver representations became less benevolent. Moreover, the Benevolence of the additional caregiver representation was found to predict these children's changes in externalizing symptoms beyond the effects of their symptomatology and its associations with the Benevolence of these representations at Time 1. PMID:19220720

  15. The Effect of Emphasizing Mathematical Structure in the Acquisition of Whole Number Computation Skills (Addition and Subtraction) By Seven- and Eight-Year Olds: A Clinical Investigation.

    ERIC Educational Resources Information Center

    Uprichard, A. Edward; Collura, Carolyn

    This investigation sought to determine the effect of emphasizing mathematical structure in the acquisition of computational skills by seven- and eight-year-olds. The meaningful development-of-structure approach emphasized closure, commutativity, associativity, and the identity element of addition; the inverse relationship between addition and…

  16. [TG-FTIR study on pyrolysis of wheat-straw with abundant CaO additives].

    PubMed

    Han, Long; Wang, Qin-Hui; Yang, Yu-Kun; Yu, Chun-Jiang; Fang, Meng-Xiang; Luo, Zhong-Yang

    2011-04-01

    Biomass pyrolysis in presence of abundant CaO additives is a fundamental process prior to CaO sorption enhanced gasification in biomass-based zero emission system. In the present study, thermogravimetric Fourier transform infrared (TG-FTIR) analysis was adopted to examine the effects of CaO additives on the mass loss process and volatiles evolution of wheat-straw pyrolysis. Observations from TG and FTIR analyses simultaneously demonstrated a two-stage process for CaO catalyzed wheat-straw pyrolysis, different from the single stage process for pure wheat-straw pyrolysis. CaO additives could not only absorb the released CO2 but also reduce the yields of tar species such as toluene, phenol, and formic acid in the first stage, resulting in decreased mass loss and maximum mass loss rate in this stage with an increase in CaO addition. The second stage was attributed to the CaCO3 decomposition and the mass loss and maximum mass loss rate increased with increasing amount of CaO additives. The results of the present study demonstrated the great potential of CaO additives to capture CO2 and reduce tars yields in biomass-based zero emission system. The gasification temperature in the system should be lowered down to avoid CaCO3 decomposition. PMID:21714234

  17. Nanostructured surfaces investigated by quantitative morphological studies.

    PubMed

    Perani, Martina; Carapezzi, Stefania; Mutta, Geeta Rani; Cavalcoli, Daniela

    2016-05-01

    The morphology of different surfaces has been investigated by atomic force microscopy and quantitatively analyzed in this paper. Two different tools have been employed to this scope: the analysis of the height-height correlation function and the determination of the mean grain size, which have been combined to obtain a complete characterization of the surfaces. Different materials have been analyzed: SiO x N y , InGaN/GaN quantum wells and Si nanowires, grown with different techniques. Notwithstanding the presence of grain-like structures on all the samples analyzed, they present very diverse surface design, underlying that this procedure can be of general use. Our results show that the quantitative analysis of nanostructured surfaces allows us to obtain interesting information, such as grain clustering, from the comparison of the lateral correlation length and the grain size. PMID:27004458

  18. Nanostructured surfaces investigated by quantitative morphological studies

    NASA Astrophysics Data System (ADS)

    Perani, Martina; Carapezzi, Stefania; Rani Mutta, Geeta; Cavalcoli, Daniela

    2016-05-01

    The morphology of different surfaces has been investigated by atomic force microscopy and quantitatively analyzed in this paper. Two different tools have been employed to this scope: the analysis of the height-height correlation function and the determination of the mean grain size, which have been combined to obtain a complete characterization of the surfaces. Different materials have been analyzed: SiO x N y , InGaN/GaN quantum wells and Si nanowires, grown with different techniques. Notwithstanding the presence of grain-like structures on all the samples analyzed, they present very diverse surface design, underlying that this procedure can be of general use. Our results show that the quantitative analysis of nanostructured surfaces allows us to obtain interesting information, such as grain clustering, from the comparison of the lateral correlation length and the grain size.

  19. SHEEP MOUNTAIN WILDERNESS STUDY AREA AND CUCAMONGA WILDERNESS AND ADDITIONS, CALIFORNIA.

    USGS Publications Warehouse

    Evans, James G.; Ridenour, James

    1984-01-01

    The Sheep Mountain Wilderness Study Area and Cucamonga Wilderness and additions encompass approximately 104 sq mi of the eastern San Gabriel Mountains, Los Angeles and San Bernardino Counties, California. A mineral survey indicates areas of probable and substantiated tungsten and gold resource potential for parts of the Sheep Mountain Wilderness Study Area and an area of probable tungsten and gold resource potential in the Cucamonga Wilderness and additions. The rugged topography, withdrawal of lands from mineral entry to protect watershed, and restricted entry of lands during periods of high fire danger have contributed to the continuing decline in mineral exploration. The geologic setting precludes the presence of energy resources.

  20. Investigating Adaptive Grieving Styles: A Delphi Study

    ERIC Educational Resources Information Center

    Doughty, Elizabeth A.

    2009-01-01

    There has been an evolution in the understanding of the nature of grief since S. Freud's initial work, Mourning and Melancholia (1917/1953). Mental health practitioners and researchers have established new models to aid in the conceptualization and treatment of grief issues. The purpose of this study was to examine the opinions of experts in the…

  1. The Translatability of Metaphor: Study and Investigation

    ERIC Educational Resources Information Center

    Alghbban, Mohammed

    2011-01-01

    The appropriate handling of the metaphorical meaning during translation, along with maximizing its level of equivalence in the target language, is going to be my central focus through the course of this dissertation. Unlike many contributions that attempt to reconcile the problem of translating metaphor, this study has come to approach the subject…

  2. Investigating the effect of additional gases in an atmospheric-pressure helium plasma jet using ambient mass spectrometry

    NASA Astrophysics Data System (ADS)

    Oh, Jun-Seok; Furuta, Hiroshi; Hatta, Akimitsu; Bradley, James W.

    2015-01-01

    Using ambient mass spectrometry, positive and negative ions created in an atmospheric-pressure plasma jet have been detected for a variation of different traces gases (Ar, N2, and O2) added to the flow, downstream of the main helium discharge plasma. We find that such additions can change the chemistry in the outflow plasma plume. For instance, small amounts of O2 increases the formation of positive ion clusters, e.g., water clusters H+(H2O)n (with n up to 5) through hydration reactions, but decreases the intensity of heavy negative ions detected. With the addition of Ar and N2 we see a marked decrease in the intensity of negative ions in the plume but with increased Ar+ and nitrous oxide ions (e.g., N2O+) for the two cases respectively. From broadband optical emission measurements of the glowing plasma we see that the relative emission intensity of OH radical were changed with addition of the four different gases but the emission spectra were not changed. A calculation of rotational temperature of OH radicals, indicates that the gas temperatures is about 290 K for the four different gas mixture cases.

  3. Investigation of plasma arc welding as a method for the additive manufacturing of titanium-(6)aluminum-(4)vanadium alloy components

    NASA Astrophysics Data System (ADS)

    Stavinoha, Joe N.

    The process of producing near net-shape components by material deposition is known as additive manufacturing. All additive manufacturing processes are based on the addition of material with the main driving forces being cost reduction and flexibility in both manufacturing and product design. With wire metal deposition, metal is deposited as beads side-by-side and layer-by-layer in a desired pattern to build a complete component or add features on a part. There are minimal waste products, low consumables, and an efficient use of energy and feedstock associated with additive manufacturing processes. Titanium and titanium alloys are useful engineering materials that possess an extraordinary combination of properties. Some of the properties that make titanium advantageous for structural applications are its high strength-to-weight ratio, low density, low coefficient of thermal expansion, and good corrosion resistance. The most commonly used titanium alloy, Ti-6Al-4V, is typically used in aerospace applications, pressure vessels, aircraft gas turbine disks, cases and compressor blades, and surgical implants. Because of the high material prices associated with titanium alloys, the production of near net-shape components by additive manufacturing is an attractive option for the manufacturing of Ti-6Al-4V alloy components. In this thesis, the manufacturing of cylindrical Ti-6Al-4V alloy specimens by wire metal deposition utilizing the plasma arc welding process was demonstrated. Plasma arc welding is a cost effective additive manufacturing technique when compared to other current additive manufacturing methods such as laser beam welding and electron beam welding. Plasma arc welding is considered a high-energy-density welding processes which is desirable for the successful welding of titanium. Metal deposition was performed using a constant current plasma arc welding power supply, flow-purged welding chamber, argon shielding and orifice gas, ERTi-5 filler metal, and Ti-6Al

  4. Generating Scenarios of Addition and Subtraction: A Study of Japanese University Students

    ERIC Educational Resources Information Center

    Kinda, Shigehiro

    2013-01-01

    Students are presented with problems involving three scenario types of addition and subtraction in elementary mathematics: one dynamic ("Change") and two static ("Combine, Compare"). Previous studies have indicated that the dynamic type is easier for school children, whereas the static types are more difficult and comprehended only gradually…

  5. 7 CFR 1710.253 - Engineering and cost studies-addition of generation capacity.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 11 2011-01-01 2011-01-01 false Engineering and cost studies-addition of generation capacity. 1710.253 Section 1710.253 Agriculture Regulations of the Department of Agriculture (Continued) RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE GENERAL AND PRE-LOAN POLICIES AND PROCEDURES COMMON TO ELECTRIC LOANS AND...

  6. 7 CFR 1710.253 - Engineering and cost studies-addition of generation capacity.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 11 2012-01-01 2012-01-01 false Engineering and cost studies-addition of generation capacity. 1710.253 Section 1710.253 Agriculture Regulations of the Department of Agriculture (Continued) RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE GENERAL AND PRE-LOAN POLICIES AND PROCEDURES COMMON TO ELECTRIC LOANS AND...

  7. Experimental study of combustion of decane, dodecane and hexadecane with polymeric and nano-particle additives

    NASA Astrophysics Data System (ADS)

    Ghamari, Mohsen; Ratner, Albert

    2015-11-01

    Recent studies have shown that adding combustible nano-particles could have promising effects on increasing burning rate of liquid fuels. Combustible nano-particles could enhance the heat conduction and mixing within the droplet. Polymers have also higher burning rate than regular hydrocarbon fuels because of having the flame closer to the droplet surface. Therefore adding polymeric additive could have the potential to increase the burning rate. In this study, combustion of stationary fuel droplets of n-Decane, n-Dodecane and n-Hexadecane doped with different percentages of a long chain polymer and also a very fine nano carbon was examined and compared with the pure hydrocarbon behavior. In contrast with hydrocarbon droplets with no polymer addition, several zones of combustion including a slow and steady burning zone, a strong swelling zone and a final fast and fairly steady combustion zone were also detected. In addition, increasing polymer percentage resulted in a more extended swelling zone and shorter slow burning zone in addition to a shorter total burning time. Addition of nano-particles also resulted in an overall increased burning rate and shortened burning time which is due to enhanced heat conduction within the droplet.

  8. A laboratory study of the perceived benefit of additional noise attenuation by houses

    NASA Technical Reports Server (NTRS)

    Flindell, I. H.

    1983-01-01

    Two Experiments were conducted to investigate the perceived benefit of additional house attenuation against aircraft flyover noise. First, subjects made annoyance judgments in a simulated living room while an operative window with real and dummy storm windows was manipulated in full view of those subjects. Second, subjects made annoyance judgments in an anechoic audiometric test chamber of frequency shaped noise signals having spectra closely matched to those of the aircraft flyover noises reproduced in the first experiment. These stimuli represented the aircraft flyover noises in levels and spectra but without the situational and visual cues present in the simulated living room. Perceptual constancy theory implies that annoyance tends to remain constant despite reductions in noise level caused by additional attenuation of which the subjects are fully aware. This theory was supported when account was taken for a reported annoyance overestimation for certain spectra and for a simulated condition cue overreaction.

  9. Enhanced flux pinning in MOCVD-YBCO films through Zr-additions:Systematic feasibility studies

    SciTech Connect

    Aytug, Tolga; Paranthaman, Mariappan Parans; Specht, Eliot D; Kim, Kyunghoon; Zhang, Yifei; Cantoni, Claudia; Zuev, Yuri L; Goyal, Amit; Christen, David K; Maroni, Victor A.

    2009-01-01

    Systematic effects of Zr additions on the structural and flux pinning properties of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (YBCO) films deposited by metal-organic chemical vapor deposition (MOCVD) have been investigated. Detailed characterization, conducted by coordinated transport, x-ray diffraction, scanning and transmission electron microscopy analyses, and imaging Raman microscopy have revealed trends in the resulting property/performance correlations of these films with respect to varying mole percentages (mol%) of added Zr. For compositions {le} 7.5 mol%, Zr additions lead to improved in-field critical current density, as well as extra correlated pinning along the c-axis direction of the YBCO films via the formation of columnar, self-assembled stacks of BaZrO{sub 3} nanodots.

  10. Enhanced flux pinning in MOCVD-YBCO films through Zr additions : systematic feasibility studies.

    SciTech Connect

    Aytug, T.; Paranthaman, M.; Specht, E. D.; Zhang, Y.; Kim, K.; Zuev, Y. L.; Cantoni, C.; Goyal, A.; Christen, D. K.; Maroni, V. A.; Chen, Y.; Selvamanickam, V.; ORNL; SuperPower, Inc.

    2010-01-01

    Systematic effects of Zr additions on the structural and flux pinning properties of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (YBCO) films deposited by metal-organic chemical vapor deposition (MOCVD) have been investigated. Detailed characterization, conducted by coordinated transport, x-ray diffraction, scanning and transmission electron microscopy analyses, and imaging Raman microscopy have revealed trends in the resulting property/performance correlations of these films with respect to varying mole percentages (mol%) of added Zr. For compositions {le} 7.5 mol%, Zr additions lead to improved in-field critical current density, as well as extra correlated pinning along the c-axis direction of the YBCO films via the formation of columnar, self-assembled stacks of BaZrO{sub 3} nanodots.

  11. Anatomically ordered tapping interferes more with one-digit addition than two-digit addition: a dual-task fMRI study.

    PubMed

    Soylu, Firat; Newman, Sharlene D

    2016-02-01

    Fingers are used as canonical representations for numbers across cultures. In previous imaging studies, it was shown that arithmetic processing activates neural resources that are known to participate in finger movements. Additionally, in one dual-task study, it was shown that anatomically ordered finger tapping disrupts addition and subtraction more than multiplication, possibly due to a long-lasting effect of early finger counting experiences on the neural correlates and organization of addition and subtraction processes. How arithmetic task difficulty and tapping complexity affect the concurrent performance is still unclear. If early finger counting experiences have bearing on the neural correlates of arithmetic in adults, then one would expect anatomically and non-anatomically ordered tapping to have different interference effects, given that finger counting is usually anatomically ordered. To unravel these issues, we studied how (1) arithmetic task difficulty and (2) the complexity of the finger tapping sequence (anatomical vs. non-anatomical ordering) affect concurrent performance and use of key neural circuits using a mixed block/event-related dual-task fMRI design with adult participants. The results suggest that complexity of the tapping sequence modulates interference on addition, and that one-digit addition (fact retrieval), compared to two-digit addition (calculation), is more affected from anatomically ordered tapping. The region-of-interest analysis showed higher left angular gyrus BOLD response for one-digit compared to two-digit addition, and in no-tapping conditions than dual tapping conditions. The results support a specific association between addition fact retrieval and anatomically ordered finger movements in adults, possibly due to finger counting strategies that deploy anatomically ordered finger movements early in the development. PMID:26410214

  12. A synchrotron study of microstructure gradient in laser additively formed epitaxial Ni-based superalloy

    NASA Astrophysics Data System (ADS)

    Xue, Jiawei; Zhang, Anfeng; Li, Yao; Qian, Dan; Wan, Jingchun; Qi, Baolu; Tamura, Nobumichi; Song, Zhongxiao; Chen, Kai

    2015-10-01

    Laser additive forming is considered to be one of the promising techniques to repair single crystal Ni-based superalloy parts to extend their life and reduce the cost. Preservation of the single crystalline nature and prevention of thermal mechanical failure are two of the most essential issues for the application of this technique. Here we employ synchrotron X-ray microdiffraction to evaluate the quality in terms of crystal orientation and defect distribution of a Ni-based superalloy DZ125L directly formed by a laser additive process rooted from a single crystalline substrate of the same material. We show that a disorientation gradient caused by a high density of geometrically necessary dislocations and resultant subgrains exists in the interfacial region between the epitaxial and stray grains. This creates a potential relationship of stray grain formation and defect accumulation. The observation offers new directions on the study of performance control and reliability of the laser additive manufactured superalloys.

  13. Microstructural Study Of Zinc Hot Dip Galvanized Coatings with Titanium Additions In The Zinc Melt

    NASA Astrophysics Data System (ADS)

    Konidaris, S.; Pistofidis, N.; Vourlias, G.; Pavlidou, E.; Stergiou, A.; Stergioudis, G.; Polychroniadis, E. K.

    2007-04-01

    Zinc hot-dip galvanizing is a method for protecting iron and steel against corrosion. Galvanizing with pure Zn or Zn with additions like Ni, Al, Pb and Bi has been extensively studied, but there is a lack of scientific information about other additions. The present work examines the effect of a 0.5 wt% Ti addition in the Zn melt. The samples were exposed to accelerated corrosion in a salt spray chamber (SSC). The microstructure and chemical composition of the coatings were determined by Optical Microscopy, XRD and SEM associated with an EDS Analyzer. The results indicate that the coatings have a typical morphology, while Zn-Ti phases were also detected.

  14. A synchrotron study of microstructure gradient in laser additively formed epitaxial Ni-based superalloy

    PubMed Central

    Xue, Jiawei; Zhang, Anfeng; Li, Yao; Qian, Dan; Wan, Jingchun; Qi, Baolu; Tamura, Nobumichi; Song, Zhongxiao; Chen, Kai

    2015-01-01

    Laser additive forming is considered to be one of the promising techniques to repair single crystal Ni-based superalloy parts to extend their life and reduce the cost. Preservation of the single crystalline nature and prevention of thermal mechanical failure are two of the most essential issues for the application of this technique. Here we employ synchrotron X-ray microdiffraction to evaluate the quality in terms of crystal orientation and defect distribution of a Ni-based superalloy DZ125L directly formed by a laser additive process rooted from a single crystalline substrate of the same material. We show that a disorientation gradient caused by a high density of geometrically necessary dislocations and resultant subgrains exists in the interfacial region between the epitaxial and stray grains. This creates a potential relationship of stray grain formation and defect accumulation. The observation offers new directions on the study of performance control and reliability of the laser additive manufactured superalloys. PMID:26446425

  15. A synchrotron study of microstructure gradient in laser additively formed epitaxial Ni-based superalloy

    SciTech Connect

    Xue, Jiawei; Zhang, Anfeng; Li, Yao; Qian, Dan; Wan, Jingchun; Qi, Baolu; Tamura, Nobumichi; Song, Zhongxiao; Chen, Kai

    2015-10-08

    Laser additive forming is considered to be one of the promising techniques to repair single crystal Ni-based superalloy parts to extend their life and reduce the cost. Preservation of the single crystalline nature and prevention of thermal mechanical failure are two of the most essential issues for the application of this technique. Here we employ synchrotron X-ray microdiffraction to evaluate the quality in terms of crystal orientation and defect distribution of a Ni-based superalloy DZ125L directly formed by a laser additive process rooted from a single crystalline substrate of the same material. We show that a disorientation gradient caused by a high density of geometrically necessary dislocations and resultant subgrains exists in the interfacial region between the epitaxial and stray grains. This creates a potential relationship of stray grain formation and defect accumulation. In conclusion, the observation offers new directions on the study of performance control and reliability of the laser additive manufactured superalloys.

  16. Studies of levels of biogenic amines in meat samples in relation to the content of additives.

    PubMed

    Jastrzębska, Aneta; Kowalska, Sylwia; Szłyk, Edward

    2016-01-01

    The impact of meat additives on the concentration of biogenic amines and the quality of meat was studied. Fresh white and red meat samples were fortified with the following food additives: citric and lactic acids, disodium diphosphate, sodium nitrite, sodium metabisulphite, potassium sorbate, sodium chloride, ascorbic acid, α-tocopherol, propyl 3,4,5-trihydroxybenzoate (propyl gallate) and butylated hydroxyanisole. The content of spermine, spermidine, putrescine, cadaverine, histamine, tyramine, tryptamine and 2-phenylethylamine was determined by capillary isotachophoretic methods in meat samples (fresh and fortified) during four days of storage at 4°C. The results were applied to estimate the impact of the tested additives on the formation of biogenic amines in white and red meat. For all tested meats, sodium nitrite, sodium chloride and disodium diphosphate showed the best inhibition. However, cadaverine and putrescine were characterised by the biggest changes in concentration during the storage time of all the additives. Based on the presented data for the content of biogenic amines in meat samples analysed as a function of storage time and additives, we suggest that cadaverine and putrescine have a significant impact on meat quality. PMID:26515667

  17. Magnetic Force Microscopy Study of Zr2Co11 -Based Nanocrystalline Materials: Effect of Mo Addition

    DOE PAGESBeta

    Yue, Lanping; Jin, Yunlong; Zhang, Wenyong; Sellmyer, David J.

    2015-01-01

    Tmore » he addition of Molybdenum was used to modify the nanostructure and enhance coercivity of rare-earth-free Zr2Co11-based nanocrystalline permanent magnets. he effect of Mo addition on magnetic domain structures of melt spun nanocrystalline Zr16Co84-xMox(x=0, 0.5, 1, 1.5, and 2.0) ribbons has been investigated. It was found that magnetic properties and local domain structures are strongly influenced by Mo doping. he coercivity of the samples increases with the increase in Mo content (x≤1.5). he maximum energy product(BH)maxincreases with increasingxfrom 0.5 MGOe forx=0to a maximum value of 4.2 MGOe forx=1.5. he smallest domain size with a relatively short magnetic correlation length of 128 nm and largest root-mean-square phase shiftΦrmsvalue of 0.66° are observed for thex=1.5. he optimal Mo addition promotes magnetic domain structure refinement and thus leads to a significant increase in coercivity and energy product in this sample.« less

  18. Use of a Generalized Additive Model to Investigate Key Abiotic Factors Affecting Microcystin Cellular Quotas in Heavy Bloom Areas of Lake Taihu

    PubMed Central

    Tao, Min; Xie, Ping; Chen, Jun; Qin, Boqiang; Zhang, Dawen; Niu, Yuan; Zhang, Meng; Wang, Qing; Wu, Laiyan

    2012-01-01

    Lake Taihu is the third largest freshwater lake in China and is suffering from serious cyanobacterial blooms with the associated drinking water contamination by microcystin (MC) for millions of citizens. So far, most studies on MCs have been limited to two small bays, while systematic research on the whole lake is lacking. To explain the variations in MC concentrations during cyanobacterial bloom, a large-scale survey at 30 sites across the lake was conducted monthly in 2008. The health risks of MC exposure were high, especially in the northern area. Both Microcystis abundance and MC cellular quotas presented positive correlations with MC concentration in the bloom seasons, suggesting that the toxic risks during Microcystis proliferations were affected by variations in both Microcystis density and MC production per Microcystis cell. Use of a powerful predictive modeling tool named generalized additive model (GAM) helped visualize significant effects of abiotic factors related to carbon fixation and proliferation of Microcystis (conductivity, dissolved inorganic carbon (DIC), water temperature and pH) on MC cellular quotas from recruitment period of Microcystis to the bloom seasons, suggesting the possible use of these factors, in addition to Microcystis abundance, as warning signs to predict toxic events in the future. The interesting relationship between macrophytes and MC cellular quotas of Microcystis (i.e., high MC cellular quotas in the presence of macrophytes) needs further investigation. PMID:22384128

  19. Use of a generalized additive model to investigate key abiotic factors affecting microcystin cellular quotas in heavy bloom areas of Lake Taihu.

    PubMed

    Tao, Min; Xie, Ping; Chen, Jun; Qin, Boqiang; Zhang, Dawen; Niu, Yuan; Zhang, Meng; Wang, Qing; Wu, Laiyan

    2012-01-01

    Lake Taihu is the third largest freshwater lake in China and is suffering from serious cyanobacterial blooms with the associated drinking water contamination by microcystin (MC) for millions of citizens. So far, most studies on MCs have been limited to two small bays, while systematic research on the whole lake is lacking. To explain the variations in MC concentrations during cyanobacterial bloom, a large-scale survey at 30 sites across the lake was conducted monthly in 2008. The health risks of MC exposure were high, especially in the northern area. Both Microcystis abundance and MC cellular quotas presented positive correlations with MC concentration in the bloom seasons, suggesting that the toxic risks during Microcystis proliferations were affected by variations in both Microcystis density and MC production per Microcystis cell. Use of a powerful predictive modeling tool named generalized additive model (GAM) helped visualize significant effects of abiotic factors related to carbon fixation and proliferation of Microcystis (conductivity, dissolved inorganic carbon (DIC), water temperature and pH) on MC cellular quotas from recruitment period of Microcystis to the bloom seasons, suggesting the possible use of these factors, in addition to Microcystis abundance, as warning signs to predict toxic events in the future. The interesting relationship between macrophytes and MC cellular quotas of Microcystis (i.e., high MC cellular quotas in the presence of macrophytes) needs further investigation. PMID:22384128

  20. Study of asphalt/asphaltene precipitation during addition of solvents to West Sak crude

    SciTech Connect

    Jiang, J.C.; Patil, S.L.; Kamath, V.A. )

    1990-07-01

    In this study, experimental data on the amount of asphalt and asphaltene precipitation due to addition of solvents to West Sak crude were gathered. The first set of tests were conducted for two types of West Sak stock tank oils. Solvents used include: ethane, carbon dioxide, propane, n-butane, n-pentane, n-heptane, Prudhoe Bay natural gas (PBG) and natural gas liquids (NGL). Effect of solvent to oil dilution ratio on the amount of precipitation was studied. Alteration of crude oil composition due to asphalt precipitation was measured using gas-liquid chromatography. A second set of experiments were conducted to measure asphaltene precipitation due to addition of CO{sub 2} to live (recombined) West Sak crude.

  1. Investigations on the effect of amino acids on acrylamide, pyrazines, and Michael addition products in model systems.

    PubMed

    Koutsidis, Georgios; Simons, Sandra P J; Thong, Yeong H; Haldoupis, Yannis; Mojica-Lazaro, Jonas; Wedzicha, Bronislaw L; Mottram, Donald S

    2009-10-14

    Acrylamide and pyrazine formation, as influenced by the incorporation of different amino acids, was investigated in sealed low-moisture asparagine-glucose model systems. Added amino acids, with the exception of glycine and cysteine and at an equimolar concentration to asparagine, increased the rate of acrylamide formation. The strong correlation between the unsubstituted pyrazine and acrylamide suggests the promotion of the formation of Maillard reaction intermediates, and in particular glyoxal, as the determining mode of action. At increased amino acid concentrations, diverse effects were observed. The initial rates of acrylamide formation remained high for valine, alanine, phenylalanine, tryptophan, glutamine, and leucine, while a significant mitigating effect, as evident from the acrylamide yields after 60 min of heating at 160 degrees C, was observed for proline, tryptophan, glycine, and cysteine. The secondary amine containing amino acids, proline and tryptophan, had the most profound mitigating effect on acrylamide after 60 min of heating. The relative importance of the competing effect of added amino acids for alpha-dicarbonyls and acrylamide-amino acid alkylation reactions is discussed and accompanied by data on the relative formation rates of selected amino acid-AA adducts. PMID:19739658

  2. The effect of Ru and Sn additions to Pt on the electrocatalysis of methanol oxidation: An in situ XAS investigation

    SciTech Connect

    Mukerjee, S.; McBreen, J.

    1997-07-01

    Elements such as Ru and Sn used as ad-atoms or as alloying elements are known to enhance methanol oxidation reaction (MOR). Ru, both as alloying element as well as upd deposited on Pt/C is widely acknowledged for enhancing MOR. Sn on the other hand is more controversial, with evidence indicating enhancements for MOR when present as upd layer and marginally effective when present as an alloying element. In situ XAS is used to investigate some of these inconsistencies in the electrocatalysis of MOR. Results indicate that alloying Sn with Pt (Pt{sub 3}Sn primary phase) causes partial filling of the Pt 5 d-band vacancies and increase in the Pt-Pt bond distances which is directly opposite to a similar situation with Ru. Upd Sn however does not perturb Pt structurally or electronically. Ru and Sn (both as alloying element and as upd ad-layer) are associated with oxygenated species, the nature and strength of the Ru. and Sn - oxygen interactions are potential dependent. Hence alloying with Sn renders Pt surface unfavorable for methanol adsorption in contrast to alloying with Ru. Both Ru and Sn however promote MOR via their ability to nucleate oxygenated species on their surface at lower potentials as compared to pure Pt.

  3. A Study of Aluminum Combustion in Solids, Powders, Foams, Additively-Manufactured Lattices, and Composites

    NASA Astrophysics Data System (ADS)

    Black, James; Trammell, Norman; Batteh, Jad; Curran, Nicholas; Rogers, John; Littrell, Donald

    2015-06-01

    This study examines the fireball characteristics, blast parameters, and combustion efficiency of explosively-shocked aluminum-based materials. The materials included structural and non-structural aluminum forms - such as solid cylinders, foams, additively-manufactured lattices, and powders - and some polytetrafluoroethylene-aluminum (PTFE-Al) composites. The materials were explosively dispersed in a small blast chamber, and the blast properties and products were measured with pressure transducers, thermocouples, slow and fast ultraviolet/visible spectrometers, and high-speed video.

  4. Spectra-temporal patterns underlying mental addition: an ERP and ERD/ERS study.

    PubMed

    Ku, Yixuan; Hong, Bo; Gao, Xiaorong; Gao, Shangkai

    2010-03-12

    Functional neuroimaging data have shown that mental calculation involves fronto-parietal areas that are composed of different subsystems shared with other cognitive functions such as working memory and language. Event-related potential (ERP) analysis has also indicated sequential information changes during the calculation process. However, little is known about the dynamic properties of oscillatory networks in this process. In the present study, we applied both ERP and event-related (de-)synchronization (ERS/ERD) analyses to EEG data recorded from normal human subjects performing tasks for sequential visual/auditory mental addition. Results in the study indicate that the late positive components (LPCs) can be decomposed into two separate parts. The earlier element LPC1 (around 360ms) reflects the computing attribute and is more prominent in calculation tasks. The later element LPC2 (around 590ms) indicates an effect of number size and appears larger only in a more complex 2-digit addition task. The theta ERS and alpha ERD show modality-independent frontal and parietal differential patterns between the mental addition and control groups, and discrepancies are noted in the beta ERD between the 2-digit and 1-digit mental addition groups. The 2-digit addition (both visual and auditory) results in similar beta ERD patterns to the auditory control, which may indicate a reliance on auditory-related resources in mental arithmetic, especially with increasing task difficulty. These results coincide with the theory of simple calculation relying on the visuospatial process and complex calculation depending on the phonological process. PMID:20105450

  5. Mineral resources of the Buffalo Hump and Sand Dunes Addition Wilderness Study Areas, Sweetwater County, Wyoming

    SciTech Connect

    Gibbons, A.B.; Barbon, H.N.; Kulik, D.M. ); McDonnell, J.R. Jr. )

    1990-01-01

    The authors present a study to assess the potential for undiscovered mineral resources and appraise the identified resources of the Buffalo Hump and Sand Dunes Addition Wilderness Study Areas, southwestern Wyoming, There are no mines, prospects, or mineralized areas nor any producing oil or gas wells; however, there are occurrences of coal, claystone and shale, and sand. There is a moderate resource potential for oil shale and natural gas and a low resource potential for oil, for metals, including uranium, and for geothermal sources.

  6. Study on the Reutilization of Clear Fracturing Flowback Fluids in Surfactant Flooding with Additives for Enhanced Oil Recovery (EOR)

    PubMed Central

    Dai, Caili; Wang, Kai; Liu, Yifei; Fang, Jichao; Zhao, Mingwei

    2014-01-01

    An investigation was conducted to study the reutilization of clear fracturing flowback fluids composed of viscoelastic surfactants (VES) with additives in surfactant flooding, making the process more efficient and cost-effective. The clear fracturing flowback fluids were used as surfactant flooding system with the addition of α-olefin sulfonate (AOS) for enhanced oil recovery (EOR). The interfacial activity, emulsification activity and oil recovery capability of the recycling system were studied. The interfacial tension (IFT) between recycling system and oil can be reduced by 2 orders of magnitude to 10−3 mN/m, which satisfies the basic demand of surfactant flooding. The oil can be emulsified and dispersed more easily due to the synergetic effect of VES and AOS. The oil-wet surface of quartz can be easily converted to water-wet through adsorption of surfactants (VES/AOS) on the surface. Thirteen core plug flooding tests were conducted to investigate the effects of AOS concentrations, slug sizes and slug types of the recycling system on the incremental oil recovery. The investigations prove that reclaiming clear fracturing flowback fluids after fracturing operation and reuse it in surfactant flooding might have less impact on environment and be more economical. PMID:25409507

  7. Additional Treatment Services in a Cocaine Treatment Study: Level of Services Obtained and Impact on Outcome

    PubMed Central

    Worley, Matthew; Gallop, Robert; Gibbons, Mary Beth Connolly; Ring-Kurtz, Sarah; Present, Julie; Weiss, Roger D.; Crits-Christoph, Paul

    2009-01-01

    The objective of this study was to examine the level of additional treatment services obtained by patients enrolled in the NIDA Cocaine Collaborative Study, a multi-center efficacy trial of four treatments for cocaine dependence, and to determine whether these services impact treatment outcome. Cocaine-dependent patients (N = 487) were recruited at five sites and randomly assigned to six months of one of four psychosocial treatments. Assessments were made at baseline, monthly during treatment, and at follow-ups at 9, 12, 15, and 18 months post-randomization. On average, patients received little or no additional treatment services during active treatment (first 6 months), but the rate of obtaining most services increased during the follow-up phase (month 7 to 18). In general, the treatment groups did not differ in the rates of obtaining non-protocol services. For all treatment groups, patients with greater psychiatric severity received more medical and psychiatric services during active treatment and follow-up. Use of treatment services was unrelated to drug use outcomes during active treatment. However, during the follow-up period, increased use of psychiatric medication, 12-step attendance, and 12-step participation was related to less drug use. The results suggest that during uncontrolled follow-up phases, additional non-protocol services may potentially confound the interpretation of treatment group comparisons in drug use outcomes. PMID:18463998

  8. Kaolinite flocculation induced by smectite addition - a transmission X-ray microscopic study.

    PubMed

    Zbik, Marek S; Song, Yen-Fang; Frost, Ray L

    2010-09-01

    The influence of smectite addition on kaolinite suspensions in water was investigated by transmission X-ray microscopy (TXM) and Scanning Electron Microscopy (SEM). Sedimentation test screening was also conducted. Micrographs were processed by the STatistic IMage Analysing (STIMAN) program and structural parameters were calculated. From the results of the sedimentation tests important influences of small smectite additions to about 3wt.% on kaolinite suspension flocculation has been found. In order to determine the reason for this smectite impact on kaolinite suspension, macroscopic behaviour micro-structural examination using Transmission X-ray Microscope (TXM) and SEM has been undertaken. TXM & SEM micrographs of freeze-dried kaolinite-smectite suspensions with up to 20% smectite showed a high degree of orientation of the fabric made of highly oriented particles and greatest density when 3wt.% of smectite was added to the 10wt.% dense kaolinite suspension. In contrast, suspensions containing pure kaolinite do not show such platelet mutual orientation but homogenous network of randomly oriented kaolinite platelets. This suggests that in kaolinite-smectite suspensions, smectite forms highly oriented basic framework into which kaolinite platelets may bond in face to face preferential contacts strengthening structure and allowing them to show plastic behaviour which is cause of platelets orientation. PMID:20621806

  9. Investigation of the O+allyl addition/elimination reaction pathways from the OCH(2)CHCH(2) radical intermediate.

    PubMed

    Fitzpatrick, Benjamin L; Lau, Kai-Chung; Butler, Laurie J; Lee, Shih-Huang; Lin, Jim Jr-Min

    2008-08-28

    These experiments study the preparation of and product channels resulting from OCH(2)CHCH(2), a key radical intermediate in the O+allyl bimolecular reaction. The data include velocity map imaging and molecular beam scattering results to probe the photolytic generation of the radical intermediate and the subsequent pathways by which the radicals access the energetically allowed product channels of the bimolecular reaction. The photodissociation of epichlorohydrin at 193.3 nm produces chlorine atoms and c-OCH(2)CHCH(2) radicals; these undergo a facile ring opening to the OCH(2)CHCH(2) radical intermediate. State-selective resonance-enhanced multiphoton ionization (REMPI) detection resolves the velocity distributions of ground and spin-orbit excited state chlorine independently, allowing for a more accurate determination of the internal energy distribution of the nascent radicals. We obtain good agreement detecting the velocity distributions of the Cl atoms with REMPI, vacuum ultraviolet (VUV) photoionization at 13.8 eV, and electron bombardment ionization; all show a bimodal distribution of recoil kinetic energies. The dominant high recoil kinetic energy feature peaks near 33 kcalmol. To elucidate the product channels resulting from the OCH(2)CHCH(2) radical intermediate, the crossed laser-molecular beam experiment uses VUV photoionization and detects the velocity distribution of the possible products. The data identify the three dominant product channels as C(3)H(4)O (acrolein)+H, C(2)H(4)+HCO (formyl radical), and H(2)CO (formaldehyde)+C(2)H(3). A small signal from C(2)H(2)O (ketene) product is also detected. The measured velocity distributions and relative signal intensities at me=27, 28, and 29 at two photoionization energies show that the most exothermic product channel, C(2)H(5)+CO, does not contribute significantly to the product branching. The higher internal energy onset of the acrolein+H product channel is consistent with the relative barriers en route to

  10. A synchrotron study of microstructure gradient in laser additively formed epitaxial Ni-based superalloy

    DOE PAGESBeta

    Xue, Jiawei; Zhang, Anfeng; Li, Yao; Qian, Dan; Wan, Jingchun; Qi, Baolu; Tamura, Nobumichi; Song, Zhongxiao; Chen, Kai

    2015-10-08

    Laser additive forming is considered to be one of the promising techniques to repair single crystal Ni-based superalloy parts to extend their life and reduce the cost. Preservation of the single crystalline nature and prevention of thermal mechanical failure are two of the most essential issues for the application of this technique. Here we employ synchrotron X-ray microdiffraction to evaluate the quality in terms of crystal orientation and defect distribution of a Ni-based superalloy DZ125L directly formed by a laser additive process rooted from a single crystalline substrate of the same material. We show that a disorientation gradient caused bymore » a high density of geometrically necessary dislocations and resultant subgrains exists in the interfacial region between the epitaxial and stray grains. This creates a potential relationship of stray grain formation and defect accumulation. In conclusion, the observation offers new directions on the study of performance control and reliability of the laser additive manufactured superalloys.« less

  11. Isomeric Selective Studies of the Dominant Addition Channel in OH Initiated Oxidation of Isoprene

    NASA Astrophysics Data System (ADS)

    Ghosh, B.; Bugarin, A.; Connell, B.; North, S. W.

    2009-12-01

    We report the first isomeric selective study of the dominant isomeric pathway in the OH initiated oxidation of isoprene in the presence of O2 and NO using the Laser Photolysis-Laser Induced Fluorescence (LP-LIF) technique. The photolysis of monodeuterated/non deuterated 2-iodo-2-methyl-but-3-en-1-ol results exclusively in the dominant OH-isoprene addition product, providing important insight into the oxidation mechanism. Based on kinetic analysis of OH cycling experiments we have determined the rate constant for O2 addition to the hydroxy alkyl radical to be (1.0±0.5) × 10^(-12) cm^(3) s^(-1) and we find a value of (8.05±2.3) × 10^(-12) cm^(3) s^(-1) for the overall reaction rate constant of the hydroxy peroxy radical with NO. We also report the first clear experimental evidence of the (E-) form of the δ-hydroxyalkoxy channel through isotopic labeling experiments and quantify its branching ratio to be 0.1±0.025. Since it corresponds to missing carbon balance in isoprene oxidation, we have been able to identify some of the missing carbon balance. Since our measured isomeric selective rate constants for the dominant outer channel in OH initiated isoprene chemistry are similar to the overall rate constants derived from non isomeric kinetics, we predict that the remaining outer addition channel will have similar reactivity. We have extended this study to the OH initiated oxidation of 1,3-butadiene. We have obtained isomeric selective rate constants on the dominant channel of the butadiene oxidation chemistry and measured the branching ratio for the δ-hydroxyalkoxy channel. These results on butadiene studies will be discussed.

  12. Immunotoxic effects of the color additive caramel color III: immune function studies in rats.

    PubMed

    Houben, G F; Penninks, A H; Seinen, W; Vos, J G; Van Loveren, H

    1993-01-01

    Administration of the color additive caramel color III (AC) may cause a reduction in total white blood cell counts in rats due to reduced lymphocyte counts. Beside lymphopenia, several other effects in rat have been described. The effects are caused by the imidazole derivative 2-acetyl-4(5)-(1,2,3,4-tetrahydroxybutyl)imidazole (THI) and occur in rats fed a diet low in vitamin B6. In the present paper, immune function studies on AC and THI with rats fed a diet low, but not deficient in vitamin B6 are presented and discussed. Rats were exposed to 0.4 or 4% AC or to 5.72 ppm THI in drinking water during and for 28 days prior to the start of immune function assays. Resistance to Trichinella spiralis was examined in an oral infection model and clearance of Listeria monocytogenes upon an intravenous infection was studied. In addition, natural cell-mediated cytotoxicity of splenic and nonadherent peritoneal cells and the antibody response to sheep red blood cells were studied. From the results it is concluded that exposure of rats to AC or THI influenced various immune function parameters. Thymus-dependent immunity was suppressed, while parameters of the nonspecific resistance were also affected, as shown by a decreased natural cell-mediated cytotoxicity in the spleen and an enhanced clearance of L. monocytogenes. PMID:8432426

  13. Improving wound care simulation with the addition of odor: a descriptive, quasi-experimental study.

    PubMed

    Roberson, Donna W; Neil, Janice A; Bryant, Elizabeth T

    2008-08-01

    Improving problem-solving skills and expertise in complex clinical care provision requires engaging students in the learning process--a challenging goal when clinical practicums and supervisors are limited. High-fidelity simulation has created many new opportunities for educating healthcare professionals. Because addressing malodorous wounds is a common problem that may be difficult to "teach," a descriptive, quasi-experimental simulation study was conducted. Following completion of a wound care simulation and Laerdal's Simulation Experience Evaluation Tool by 137 undergraduate nursing students, 50 control subjects were randomly selected and 49 volunteer students (experimental group) participated in a wound care simulation after one of three cheeses with a strong odor was added to simulate a malodorous wound. Compared to the control group, study group responses were significantly better (P <0.001) for eight of the 12 survey variables tested and indicated the addition of odor was beneficial in enhancing the perceived realism and value of the simulation. Students responded that the addition of odor in the simulation laboratory improved realism and they felt better prepared to handle malodorous wounds in a clinical setting. An unanticipated outcome was the enhanced feeling of involvement associated with paired care teams as opposed to working in larger groups. The results of this study indicate that wound care education outcomes improve when nursing students are able to practice using a multi-sensorial wound care simulation model. PMID:18716340

  14. 42 CFR 431.713 - Continuing study and investigation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Continuing study and investigation. 431.713 Section... Programs for Licensing Nursing Home Administrators § 431.713 Continuing study and investigation. The agency or board must conduct a continuing study of nursing homes and administrators within the State...

  15. 42 CFR 431.713 - Continuing study and investigation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 4 2011-10-01 2011-10-01 false Continuing study and investigation. 431.713 Section... Programs for Licensing Nursing Home Administrators § 431.713 Continuing study and investigation. The agency or board must conduct a continuing study of nursing homes and administrators within the State...

  16. In situ vitrification and the effects of soil additives; A mixture experiment case study

    SciTech Connect

    Piepel, G.F.; Shade, J.W. )

    1992-01-01

    This paper presents a case study involving in situ vitrification (ISV), a process for immobilizing chemical or nuclear wastes in soil by melting-dissolving the contaminated soil into a glass block. One goal of the study was to investigate how viscosity and electrical conductivity were affected by mixing CaO and Na{sub 2}O with soil. A three-component constrained-region mixture experiment design was generated and the viscosity and electrical conductivity data collected. Several second-order mixture models were considered, and the Box-Cox transformation technique was applied to select property transformations. The fitted models were used to produce contour and component effects plots.

  17. In situ7Li and 133Cs nuclear magnetic resonance investigations on the role of Cs+ additive in lithium-metal deposition process

    NASA Astrophysics Data System (ADS)

    Hu, Jian Zhi; Zhao, Zhenchao; Hu, Mary Y.; Feng, Ju; Deng, Xuchu; Chen, Xilin; Xu, Wu; Liu, Jun; Zhang, Ji-Guang

    2016-02-01

    Cesium ion (Cs+) has been reported to be an effective electrolyte additive to suppress Li dendrite growth which prevents the application of lithium (Li) metal as an anode for rechargeable Li batteries. In this work, we investigated the effect of Cs+ additive on Li depositions using quantitative in situ7Li and 133Cs nuclear magnetic resonance (NMR) with planar symmetric Li cells. It's found that the addition of Cs+ can significantly enhance both the formation of well aligned Li nanorods and reversibility of the Li electrode. In situ133Cs NMR directly confirms that Cs+ migrates to Li electrode to form a positively charged electrostatic shield during the charging process. Much more electrochemical "active" Li was found in Li films deposited with Cs+ additive, while more electrochemical "dead" and thicker Li rods were identified in Li films deposited without Cs+. Combining the in situ and the previous ex-situ results, a Li deposition model has been proposed to explain these observations.

  18. A water soluble additive to suppress respirable dust from concrete-cutting chainsaws: a case study.

    PubMed

    Summers, Michael P; Parmigiani, John P

    2015-01-01

    Respirable dust is of particular concern in the construction industry because it contains crystalline silica. Respirable forms of silica are a severe health threat because they heighten the risk of numerous respirable diseases. Concrete cutting, a common work practice in the construction industry, is a major contributor to dust generation. No studies have been found that focus on the dust suppression of concrete-cutting chainsaws, presumably because, during normal operation water is supplied continuously and copiously to the dust generation points. However, there is a desire to better understand dust creation at low water flow rates. In this case study, a water-soluble surfactant additive was used in the chainsaw's water supply. Cutting was performed on a free-standing concrete wall in a covered outdoor lab with a hand-held, gas-powered, concrete-cutting chainsaw. Air was sampled at the operator's lapel, and around the concrete wall to simulate nearby personnel. Two additive concentrations were tested (2.0% and 0.2%), across a range of fluid flow rates (0.38-3.8 Lpm [0.1-1.0 gpm] at 0.38 Lpm [0.1 gpm] increments). Results indicate that when a lower concentration of additive is used exposure levels increase. However, all exposure levels, once adjusted for 3 hours of continuous cutting in an 8-hour work shift, are below the Occupational Safety and Health Administration (OSHA) permissible exposure limit (PEL) of 5 mg/m(3). Estimates were made using trend lines to predict the fluid flow rates that would cause respirable dust exposure to exceed both the OSHA PEL and the American Conference of Governmental Industrial Hygienists (ACGIH®) threshold limit value (TLV). PMID:25714034

  19. Role of sulfite additives in wine induced asthma: single dose and cumulative dose studies

    PubMed Central

    Vally, H; Thompson, P

    2001-01-01

    BACKGROUND—Wine appears to be a significant trigger for asthma. Although sulfite additives have been implicated as a major cause of wine induced asthma, direct evidence is limited. Two studies were undertaken to assess sulfite reactivity in wine sensitive asthmatics. The first study assessed sensitivity to sulfites in wine using a single dose sulfited wine challenge protocol followed by a double blind, placebo controlled challenge. In the second study a cumulative dose sulfited wine challenge protocol was employed to establish if wine sensitive asthmatics as a group have an increased sensitivity to sulfites.
METHODS—In study 1, 24 asthmatic patients with a strong history of wine induced asthma were screened. Subjects showing positive responses to single blind high sulfite (300 ppm) wine challenge were rechallenged on separate days in a double blind, placebo controlled fashion with wines of varying sulfite levels to characterise their responses to these drinks. In study 2, wine sensitive asthmatic patients (n=12) and control asthmatics (n=6) were challenged cumulatively with wine containing increasing concentrations of sulfite in order to characterise further their sensitivity to sulfites in wine.
RESULTS—Four of the 24 self-reporting wine sensitive asthmatic patients were found to respond to sulfite additives in wine when challenged in a single dose fashion (study 1). In the double blind dose-response study all four had a significant fall in forced expiratory volume in one second (FEV1) (>15% from baseline) following exposure to wine containing 300 ppm sulfite, but did not respond to wines containing 20, 75 or 150 ppm sulfite. Responses were maximal at 5 minutes (mean (SD) maximal decline in FEV1 28.7 (13)%) and took 15-60 minutes to return to baseline levels. In the cumulative dose-response study (study 2) no significant difference was observed in any of the lung function parameters measured (FEV1, peak expiratory flow (PEF), mid phase forced expiratory

  20. Characterization studies on the additives mixed L-arginine phosphate monohydrate (LAP) crystals

    NASA Astrophysics Data System (ADS)

    Haja Hameed, A. S.; Karthikeyan, C.; Ravi, G.; Rohani, S.

    2011-04-01

    L-arginine phosphate monohydrate (LAP), potassium thiocyanate (KSCN) mixed LAP (LAP:KSCN) and sodium sulfite (Na 2SO 3) mixed LAP (LAP:Na 2SO 3) single crystals were grown by slow cooling technique. The effect of microbial contamination and coloration on the growth solutions was studied. The crystalline powders of the grown crystals were examined by X-ray diffraction and the lattice parameters of the crystals were estimated. From the FTIR spectroscopic analysis, various functional group frequencies associated with the crystals were assigned. Vickers microhardness studies were done on {1 0 0} faces for pure and additives mixed LAP crystals. From the preliminary surface second harmonic generation (SHG) results, it was found that the SHG intensity at (1 0 0) face of LAP:KSCN crystal was much stronger than that of pure LAP.

  1. Prazosin addition to fluvoxamine: A preclinical study and open clinical trial in OCD.

    PubMed

    Feenstra, Matthijs G P; Klompmakers, André; Figee, Martijn; Fluitman, Sjoerd; Vulink, Nienke; Westenberg, Herman G M; Denys, Damiaan

    2016-02-01

    The efficacy of selective serotonin reuptake inhibitors (SRIs) in psychiatric disorders may be "augmented" through the addition of atypical antipsychotic drugs. A synergistic increase in dopamine (DA) release in the prefrontal cortex has been suggested to underlie this augmentation effect, though the mechanism of action is not clear yet. We used in vivo microdialysis in rats to study DA release following the administration of combinations of fluvoxamine (10 mg/kg) and quetiapine (10 mg/kg) with various monoamine-related drugs. The results confirmed that the selective 5-HT1A antagonist WAY-100635 (0.05 mg/kg) partially blocked the fluvoxamine-quetiapine synergistic effect (maximum DA increase dropped from 325% to 214%). A novel finding is that the α1-adrenergic blocker prazosin (1 mg/kg), combined with fluvoxamine, partially mimicked the effect of augmentation (maximum DA increase 205%; area-under-the-curve 163%). As this suggested that prazosin augmentation might be tested in a clinical study, we performed an open clinical trial of prazosin 20 mg addition to SRI in therapy-resistant patients with obsessive-compulsive disorder applying for neurosurgery. A small, non-significant reduction in Yale Brown Obsessive Compulsive Scale (Y-BOCS) scores was observed in 10 patients and one patient was classified as a responder with a reduction in Y-BOCS scores of more than 25%. We suggest that future clinical studies augmenting SRIs with an α1-adrenergic blocker in less treatment resistant cases should be considered. The clinical trial "Prazosin in combination with a serotonin reuptake inhibitor for patients with Obsessive Compulsive disorder: an open label study" was registered at 24/05/2011 under trial number ISRCTN61562706: http://www.controlled-trials.com/ISRCTN61562706. PMID:26712326

  2. Voice measures of workload in the advanced flight deck: Additional studies

    NASA Technical Reports Server (NTRS)

    Schneider, Sid J.; Alpert, Murray

    1989-01-01

    These studies investigated acoustical analysis of the voice as a measure of workload in individual operators. In the first study, voice samples were recorded from a single operator during high, medium, and low workload conditions. Mean amplitude, frequency, syllable duration, and emphasis all tended to increase as workload increased. In the second study, NASA test pilots performed a laboratory task, and used a flight simulator under differing work conditions. For two of the pilots, high workload in the simulator brought about greater amplitude, peak duration, and stress. In both the laboratory and simulator tasks, high workload tended to be associated with more statistically significant drop-offs in the acoustical measures than were lower workload levels. There was a great deal of intra-subject variability in the acoustical measures. The results suggested that in individual operators, increased workload might be revealed by high initial amplitude and frequency, followed by rapid drop-offs over time.

  3. Study on Type C Coal Fly ash as an Additive to Molding Sand for Steel Casting

    NASA Astrophysics Data System (ADS)

    Palaniappan, Jayanthi

    2016-05-01

    Study of physio-chemical properties studies such as granulometric analysis, moisture, X ray fluorescence etc. were performed with Type C coal—combustion fly ash to investigate their potential as a distinct option for molding sand in foundry, thereby reducing the dependency on latter. Technological properties study such as compressive strength, tensile strength, permeability and compaction of various compositions of fly ash molding sand (10, 20 and 30 % fly ash substitute to chemically bonded sand) were performed and compared with silica molding sand. Steel casting production using this fly ash molding sand was done and the casting surface finish and typical casting parameters were assessed. It was noted that a good quality steel casting could be produced using type C fly ash molding sand, which effectively replaced 20 % of traditional molding sand and binders thereby providing greater financial profits to the foundry and an effective way of fly ash utilization (waste management).

  4. Impact of contacting study authors to obtain additional data for systematic reviews: diagnostic accuracy studies for hepatic fibrosis

    PubMed Central

    2014-01-01

    Background Seventeen of 172 included studies in a recent systematic review of blood tests for hepatic fibrosis or cirrhosis reported diagnostic accuracy results discordant from 2 × 2 tables, and 60 studies reported inadequate data to construct 2 × 2 tables. This study explores the yield of contacting authors of diagnostic accuracy studies and impact on the systematic review findings. Methods Sixty-six corresponding authors were sent letters requesting additional information or clarification of data from 77 studies. Data received from the authors were synthesized with data included in the previous review, and diagnostic accuracy sensitivities, specificities, and positive and likelihood ratios were recalculated. Results Of the 66 authors, 68% were successfully contacted and 42% provided additional data for 29 out of 77 studies (38%). All authors who provided data at all did so by the third emailed request (ten authors provided data after one request). Authors of more recent studies were more likely to be located and provide data compared to authors of older studies. The effects of requests for additional data on the conclusions regarding the utility of blood tests to identify patients with clinically significant fibrosis or cirrhosis were generally small for ten out of 12 tests. Additional data resulted in reclassification (using median likelihood ratio estimates) from less useful to moderately useful or vice versa for the remaining two blood tests and enabled the calculation of an estimate for a third blood test for which previously the data had been insufficient to do so. We did not identify a clear pattern for the directional impact of additional data on estimates of diagnostic accuracy. Conclusions We successfully contacted and received results from 42% of authors who provided data for 38% of included studies. Contacting authors of studies evaluating the diagnostic accuracy of serum biomarkers for hepatic fibrosis and cirrhosis in hepatitis C patients

  5. A study of pyrazines in cigarettes and how additives might be used to enhance tobacco addiction

    PubMed Central

    Alpert, Hillel R; Agaku, Israel T; Connolly, Gregory N

    2016-01-01

    Background Nicotine is known as the drug that is responsible for the addicted behaviour of tobacco users, but it has poor reinforcing effects when administered alone. Tobacco product design features enhance abuse liability by (A) optimising the dynamic delivery of nicotine to central nervous system receptors, and affecting smokers’ withdrawal symptoms, mood and behaviour; and (B) effecting conditioned learning, through sensory cues, including aroma, touch and visual stimulation, to create perceptions of pending nicotine reward. This study examines the use of additives called ‘pyrazines’, which may enhance abuse potential, their introduction in ‘lights’ and subsequently in the highly market successful Marlboro Lights (Gold) cigarettes and eventually many major brands. Methods We conducted internal tobacco industry research using online databases in conjunction with published scientific literature research, based on an iterative feedback process. Results Tobacco manufacturers developed the use of a range of compounds, including pyrazines, in order to enhance ‘light’ cigarette products’ acceptance and sales. Pyrazines with chemosensory and pharmacological effects were incorporated in the first ‘full-flavour, low-tar’ product achieving high market success. Such additives may enhance dependence by helping to optimise nicotine delivery and dosing and through cueing and learned behaviour. Conclusions Cigarette additives and ingredients with chemosensory effects that promote addiction by acting synergistically with nicotine, increasing product appeal, easing smoking initiation, discouraging cessation or promoting relapse should be regulated by the US Food and Drug Administration. Current models of tobacco abuse liability could be revised to include more explicit roles with regard to non-nicotine constituents that enhance abuse potential. PMID:26063608

  6. 42 CFR 431.713 - Continuing study and investigation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Programs for Licensing Nursing Home Administrators § 431.713 Continuing study and investigation. The agency or board must conduct a continuing study of nursing homes and administrators within the State...

  7. 42 CFR 431.713 - Continuing study and investigation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Programs for Licensing Nursing Home Administrators § 431.713 Continuing study and investigation. The agency or board must conduct a continuing study of nursing homes and administrators within the State...

  8. 42 CFR 431.713 - Continuing study and investigation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Programs for Licensing Nursing Home Administrators § 431.713 Continuing study and investigation. The agency or board must conduct a continuing study of nursing homes and administrators within the State...

  9. NASA selects scientific investigations for Earth dynamics studies

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Forty two domestic investigators affiliated with U.S. universities, governmental agencies, or private concerns and 14 investigators from France, West Germany, the Netherlands, Switzerland, Spain, Sweden, Australia, New Zealand, Venezuela, and Canada were selected to use precise geodetic data obtained by laser ranging and very long base interferometry in a study of the Earth's tectonic plate movement, crustal deformation, and rotational dynamics. The studies to be made and the principal investigators for each are listed.

  10. A Mechanistic Study of Halogen Addition and Photoelimination from π-Conjugated Tellurophenes.

    PubMed

    Carrera, Elisa I; Lanterna, Anabel E; Lough, Alan J; Scaiano, Juan C; Seferos, Dwight S

    2016-03-01

    The ability to drive reactivity using visible light is of importance for many disciplines of chemistry and has significant implications for sustainable chemistry. Identifying photochemically active compounds and understanding photochemical mechanisms is important for the development of useful materials for synthesis and catalysis. Here we report a series of photoactive diphenyltellurophene compounds bearing electron-withdrawing and electron-donating substituents synthesized by alkyne coupling/ring closing or palladium-catalyzed ipso-arylation chemistry. The redox chemistry of these compounds was studied with respect to oxidative addition and photoelimination of bromine, which is of importance for energy storage reactions involving X2. The oxidative addition reaction mechanism was studied using density functional theory, the results of which support a three-step mechanism involving the formation of an initial η(1) association complex, a monobrominated intermediate, and finally the dibrominated product. All of the tellurophene derivatives undergo photoreduction using 430, 447, or 617 nm light depending on the absorption properties of the compound. Compounds bearing electron-withdrawing substituents have the highest photochemical quantum efficiencies in the presence of an alkene trap, with efficiencies of up to 42.4% for a pentafluorophenyl-functionalized tellurophene. The photoelimination reaction was studied in detail through bromine trapping experiments and laser flash photolysis, and a mechanism is proposed. The photoreaction, which occurs by release of bromine radicals, is competitive with intersystem crossing to the triplet state of the brominated species, as evidenced by the formation of singlet oxygen. These findings should be useful for the design of new photochemically active compounds supported by main-group elements. PMID:26853739

  11. Study of mandible reconstruction using a fibula flap with application of additive manufacturing technology

    PubMed Central

    2014-01-01

    Background This study aimed to establish surgical guiding techniques for completing mandible lesion resection and reconstruction of the mandible defect area with fibula sections in one surgery by applying additive manufacturing technology, which can reduce the surgical duration and enhance the surgical accuracy and success rate. Methods A computer assisted mandible reconstruction planning (CAMRP) program was used to calculate the optimal cutting length and number of fibula pieces and design the fixtures for mandible cutting, registration, and arrangement of the fibula segments. The mandible cutting and registering fixtures were then generated using an additive manufacturing system. The CAMRP calculated the optimal fibula cutting length and number of segments based on the location and length of the defective portion of the mandible. The mandible cutting jig was generated according to the boundary surface of the lesion resection on the mandible STL model. The fibular cutting fixture was based on the length of each segment, and the registered fixture was used to quickly arrange the fibula pieces into the shape of the defect area. In this study, the mandibular lesion was reconstructed using registered fibular sections in one step, and the method is very easy to perform. Results and conclusion The application of additive manufacturing technology provided customized models and the cutting fixtures and registered fixtures, which can improve the efficiency of clinical application. This study showed that the cutting fixture helped to rapidly complete lesion resection and fibula cutting, and the registered fixture enabled arrangement of the fibula pieces and allowed completion of the mandible reconstruction in a timely manner. Our method can overcome the disadvantages of traditional surgery, which requires a long and different course of treatment and is liable to cause error. With the help of optimal cutting planning by the CAMRP and the 3D printed mandible resection jig and

  12. Resources allocation in healthcare for cancer: a case study using generalised additive mixed models.

    PubMed

    Musio, Monica; Sauleau, Erik A; Augustin, Nicole H

    2012-11-01

    Our aim is to develop a method for helping resources re-allocation in healthcare linked to cancer, in order to replan the allocation of providers. Ageing of the population has a considerable impact on the use of health resources because aged people require more specialised medical care due notably to cancer. We propose a method useful to monitor changes of cancer incidence in space and time taking into account two age categories, according to healthcar general organisation. We use generalised additive mixed models with a Poisson response, according to the methodology presented in Wood, Generalised additive models: an introduction with R. Chapman and Hall/CRC, 2006. Besides one-dimensional smooth functions accounting for non-linear effects of covariates, the space-time interaction can be modelled using scale invariant smoothers. Incidence data collected by a general cancer registry between 1992 and 2007 in a specific area of France is studied. Our best model exhibits a strong increase of the incidence of cancer along time and an obvious spatial pattern for people more than 70 years with a higher incidence in the central band of the region. This is a strong argument for re-allocating resources for old people cancer care in this sub-region. PMID:23242683

  13. Covalent binding of aniline to humic substances. 2. 15N NMR studies of nucleophilic addition reactions

    USGS Publications Warehouse

    Thorn, K.A.; Pettigrew, P.J.; Goldenberg, W.S.; Weber, E.J.

    1996-01-01

    Aromatic amines are known to undergo covalent binding with humic substances in the environment. Although previous studies have examined reaction conditions and proposed mechanisms, there has been no direct spectroscopic evidence for the covalent binding of the amines to the functional groups in humic substances. In order to further elucidate the reaction mechanisms, the Suwannee River and IHSS soil fulvic and humic acids were reacted with 15N-labeled aniline at pH 6 and analyzed using 15N NMR spectrometry. Aniline underwent nucleophilic addition reactions with the quinone and other carbonyl groups in the samples and became incorporated in the form of anilinohydroquinone, anilinoquinone, anilide, imine, and heterocyclic nitrogen, the latter comprising 50% or more of the bound amine. The anilide and anilinohydroquinone nitrogens were determined to be susceptible to chemical exchange by ammonia. In the case of Suwannee River fulvic acid, reaction under anoxic conditions and pretreatment with sodium borohydride or hydroxylamine prior to reaction under oxic conditions resulted in a decrease in the proportion of anilinohydroquinone nitrogen incorporated. The relative decrease in the incorporation of anilinohydroquinone nitrogen with respect to anilinoquinone nitrogen under anoxic conditions suggested that inter- or intramolecular redox reactions accompanied the nucleophilic addition reactions.

  14. Toxicogenomics concepts and applications to study hepatic effects of food additives and chemicals

    SciTech Connect

    Stierum, Rob . E-mail: stierum@voeding.tno.nl; Heijne, Wilbert; Kienhuis, Anne; Ommen, Ben van; Groten, John

    2005-09-01

    Transcriptomics, proteomics and metabolomics are genomics technologies with great potential in toxicological sciences. Toxicogenomics involves the integration of conventional toxicological examinations with gene, protein or metabolite expression profiles. An overview together with selected examples of the possibilities of genomics in toxicology is given. The expectations raised by toxicogenomics are earlier and more sensitive detection of toxicity. Furthermore, toxicogenomics will provide a better understanding of the mechanism of toxicity and may facilitate the prediction of toxicity of unknown compounds. Mechanism-based markers of toxicity can be discovered and improved interspecies and in vitro-in vivo extrapolations will drive model developments in toxicology. Toxicological assessment of chemical mixtures will benefit from the new molecular biological tools. In our laboratory, toxicogenomics is predominantly applied for elucidation of mechanisms of action and discovery of novel pathway-supported mechanism-based markers of liver toxicity. In addition, we aim to integrate transcriptome, proteome and metabolome data, supported by bioinformatics to develop a systems biology approach for toxicology. Transcriptomics and proteomics studies on bromobenzene-mediated hepatotoxicity in the rat are discussed. Finally, an example is shown in which gene expression profiling together with conventional biochemistry led to the discovery of novel markers for the hepatic effects of the food additives butylated hydroxytoluene, curcumin, propyl gallate and thiabendazole.

  15. Assessment of Nano Cellulose from Peach Palm Residue as Potential Food Additive: Part II: Preliminary Studies.

    PubMed

    Andrade, Dayanne Regina Mendes; Mendonça, Márcia Helena; Helm, Cristiane Vieira; Magalhães, Washington L E; de Muniz, Graciela Ines Bonzon; Kestur, Satyanarayana G

    2015-09-01

    High consumption of dietary fibers in the diet is related to the reduction of the risk of non-transmitting of chronic diseases, prevention of the constipation etc. Rich diets in dietary fibers promote beneficial effects for the metabolism. Considering the above and recognizing the multifaceted advantages of nano materials, there have been many attempts in recent times to use the nano materials in the food sector including as food additive. However, whenever new product for human and animal consumption is developed, it has to be tested for their effectiveness regarding improvement in the health of consumers, safety aspects and side effects. However, before it is tried with human beings, normally such materials would be assessed through biological tests on a living organism to understand its effect on health condition of the consumer. Accordingly, based on the authors' finding reported in a previous paper, this paper presents body weight, biochemical (glucose, cholesterol and lipid profile in blood, analysis of feces) and histological tests carried out with biomass based cellulose nano fibrils prepared by the authors for its possible use as food additive. Preliminary results of the study with mice have clearly brought out potential of these fibers for the said purpose. PMID:26344977

  16. Chromosome studies in the aquatic monocots of Myanmar: A brief review with additional records

    PubMed Central

    2014-01-01

    Abstract Myanmar (Burma) constitutes a significant component of the Indo-Myanmar biodiversity hotspot, with elements of the Indian, the Indochina, and the Sino-Japanese floristic regions, yet thus far only a few reliable sources of the country's flora have been available. As a part of a contribution for the floristic inventory of Myanmar, since it is important in a floristic survey to obtain as much information as possible, in addition to previous two reports, here we present three more chromosome counts in the aquatic monocots of Myanmar: Limnocharis flava with 2n = 20, Sagittaria trifolia with 2n = 22 (Alismataceae), and Potamogeton distinctus × Potamogeton nodosus with 2n = 52 (Potamogetonaceae); the third one is new to science. A brief review of cytological researches in the floristic regions' 45 non-hybrid aquatic monocots plus well investigated two inter-specific hybrids that are recorded in Myanmar is given, indicating that the further works with a focus on species in Myanmar that has infra-specific chromosome variation in the floristic regions will address the precise evolutionary history of the aquatic flora of Myanmar. PMID:24891826

  17. Comparative study of dimensional accuracy of different impression techniques using addition silicone impression material.

    PubMed

    Penaflor, C F; Semacio, R C; De Las Alas, L T; Uy, H G

    1998-01-01

    This study compared dimensional accuracy of the single, double with spacer, double with cut-out and double mix impression technique using addition silicone impression material. A typhodont containing Ivorine teeth model with six (6) full-crown tooth preparations were used as the positive control. Two stone replication models for each impression technique were made as test materials. Accuracy of the techniques were assessed by measuring four dimensions on the stone dies poured from the impression of the Ivorine teeth model. Results indicated that most of the measurements for the height, width and diameter slightly decreased and a few increased compared with the Ivorine teeth model. The double with cut-out and double mix technique presents the least difference from the master model as compared to the two latter impression techniques. PMID:10202524

  18. Study on Friction and Wear Properties of Silver Matrix Brush Material with Different Additives

    NASA Astrophysics Data System (ADS)

    Chen, Xiaoli; Wang, Wenfang; Hong, Yu; Wu, Yucheng

    2013-07-01

    Friction and wear processes of AgCuX (G, CF and AlN) composites-CuAgV alloy friction pair and effects of different additive content in silver based composite on friction and wear behavior are studied in this paper. The microstructure of the brush wear surface is observed by SEM. The results show that when graphite content is up to 9 wt.%, Ag-Cu-CF-G composite exhibits the best wear properties; when the content of aluminum nitride is up to 0.5 wt.%, Ag-Cu-AlN-G composites has the most comprehensive performance. The wear loss of both composites arises with the increase of both pressure and speed, but when speed reaches a critical value, the increased amplitude of wear loss tends to be steady.

  19. Thermal analysis studies of Ge additive of Se-Te glasses

    NASA Astrophysics Data System (ADS)

    Mohamed, M.; Abdel-Rahim, M. A.

    2016-04-01

    Ge x Se50Te50- x ( x = 5, 15, 20, 35 at.%) bulk glasses were synthesized by the melt quenching method. The amorphous nature of the investigated glasses was determined by X-ray diffraction. Results of differential scanning calorimetry (DSC) of the studied compositions under non-isothermal conditions were reported and discussed. The glass transition temperature ( T g), onset crystallization temperature ( T c), and crystallization peak temperature ( T p) were determined from DSC traces at different heating rates. It was found that the values of T g, T c, and T p rely on both composition and heating rate. A double crystallization stages were observed in the DSC results. Various kinetics parameters such as the glass transition energy ( E g), crystallization activation energy ( E c), and rate constant ( K p) were calculated. The glass-forming ability of the studied compositions was discussed as function of the determined kinetics parameters.

  20. Serum Potassium and Glucose Regulation in the ADDITION-Leicester Screening Study

    PubMed Central

    Carter, Patrice; Bodicoat, Danielle H.; Quinn, Lauren M.; Zaccardi, Francesco; Webb, David R.; Khunti, Kamlesh; Davies, Melanie J.

    2015-01-01

    Introduction. Previous observational studies have shown conflicting results between plasma K+ concentrations and risk of type 2 diabetes. To help clarify the evidence we aimed to determine whether an association existed between serum K+ and glucose regulation within a UK multiethnic population. Methods. Participants were recruited as part of the ADDITION Leicester study, a population based screening study. Individuals from primary care between the age of 40 and 75 years if White European or 25 and 75 years if South Asian or Afro Caribbean were recruited. Tests for associations between baseline characteristics and K+ quartiles were conducted using linear regression models. Results. Data showed individuals in the lowest K+ quartile had significantly greater 2-hour glucose levels (0.53 mmol/L, 95% CI: 0.36 to 0.70, P ≤ 0.001) than those in the highest K+ quartile. This estimation did not change with adjustment for potential confounders. Conversely, participants in the lowest K+ quartile had a 0.14% lower HbA1c (95% CI −0.19 to −0.10: P ≤ 0.001) compared to those in the highest K+ quartile. Conclusion. This cross-sectional analysis demonstrated that lower K+ was associated with greater 2 hr glucose. The data supports the possibility that K+ may influence glucose regulation and further research is warranted. PMID:25883988

  1. Study of triallyl phosphate as an electrolyte additive for high voltage lithium-ion cells

    NASA Astrophysics Data System (ADS)

    Xia, J.; Madec, L.; Ma, L.; Ellis, L. D.; Qiu, W.; Nelson, K. J.; Lu, Z.; Dahn, J. R.

    2015-11-01

    The role of triallyl phosphate as an electrolyte additive in Li(Ni0.42Mn0.42Co0.16)O2/graphite pouch cells was studied using ex-situ gas measurements, ultra high precision coulometry, automated storage experiments, electrochemical impedance spectroscopy, long-term cycling and X-ray photoelectron spectroscopy. Cells containing triallyl phosphate produced less gas during formation, cycling and storage than control cells. The use of triallyl phosphate led to higher coulombic efficiency and smaller charge endpoint capacity slippage during ultra high precision charger testing. Cells containing triallyl phosphate showed smaller potential drop during 500 h storage at 40 °C and 60 °C and the voltage drop decreased as the triallyl phosphate content in the electrolyte increased. However, large amounts of triallyl phosphate (>3% by weight in the electrolyte) led to large impedance after cycling and storage. Symmetric cell studies showed large amounts of triallyl phosphate (5% or more) led to significant impedance increase at both negative and positive electrodes. X-ray photoelectron spectroscopy studies suggested that the high impedance came from the polymerization of triallyl phosphate molecules which formed thick solid electrolyte interphase films at the surfaces of both negative and positive electrodes. An optimal amount of 2%-3% triallyl phosphate led to better capacity retention during long term cycling.

  2. Prefrontal cortex activity during motor tasks with additional mental load requiring attentional demand: a near-infrared spectroscopy study.

    PubMed

    Mandrick, Kevin; Derosiere, Gérard; Dray, Gérard; Coulon, Denis; Micallef, Jean-Paul; Perrey, Stéphane

    2013-07-01

    Functional near-infrared spectroscopy (fNIRS) is suitable for investigating cerebral oxygenation changes during motor and/or mental tasks. In the present study, we investigated how an additional mental load during a motor task at two submaximal loadings affects the fNIRS-measured brain activation over the right prefrontal cortex (PFC). Fifteen healthy males performed isometric grasping contractions at 15% and 30% of the maximal voluntary contraction (MVC) with or without an additional mental (i.e., arithmetic) task. Mental performance, force variability, fNIRS and subjective perception responses were measured in each condition. The performance of the mental task decreased significantly while the force variability increased significantly at 30% MVC as compared to 15% MVC, suggesting that performance of dual-task required more attentional resources. PFC activity increased significantly as the effort increased from 15% to 30% MVC (p<.001). Although a larger change in the deoxyhemoglobin was observed in dual-task conditions (p=.051), PFC activity did not change significantly as compared to the motor tasks alone. In summary, participants were unable to invest more attention and effort in performing the more difficult levels in order to maintain adequate mental performance. PMID:23665138

  3. Spectroscopic Evidence for Covalent Binding of Sulfadiazine to Natural Soils via 1,4-nucleophilic addition (Michael Type Addition) studied by Spin Labeling ESR

    NASA Astrophysics Data System (ADS)

    Aleksandrova, Olga

    2015-04-01

    Among different classes of veterinary pharmaceuticals, Sulfadiazine (SDZ) is widely used in animal husbandry. Its residues were detected in different environmental compartments. However, soil is a hot spot for SDZ as it receives a large portion of excreted compounds through the application of manure during soil fertilization. Ample studies on the fate of SDZ in soils showed that a large portion forms nonextractable residues (NER) along with transformation products and a low mineralization (Mueller et al., 2013). A common observation was an initially fast formation of NER up to 10% of the applied amount promptly after the application of SDZ to soil, and this portion increased up to 50% within a few days (Mueller et al., 2013; Nowak et al., 2011). A common finding for SDZ, as for other sulfonamides, was biphasic kinetics of the formation of NER, which was attributed to the occurrence of two reaction processes: a rapid, often reversible process and a slower, irreversible process (Weber et al., 1996). A single-phase reaction process was also established under anaerobic treatment (Gulkowska et al., 2014). A major focus of this work is to elucidate a reaction mechanism of covalent binding of SDZ to soil that is currently required to estimate a risk of NER formed by SDZ in soils for human health. Taking into account a key role of the amine functional groups of SDZ on its reactivity in soil, nitroxide radicals with the sewed aromatic or aliphatic amines labeled soil samples and then, were investigated by means of ESR spectroscopy. 2,5,5-Trimethyl-2-(3-aminophenyl)pyrrolidin-1-yloxy and 4-amino-2,2,6,6-Tetramethylpiperidin-1-oxyl modeled decomposition products of SDZ with the aromatic and aliphatic amines, respectively. The application of the defined combination of both spin labels (SL) to different soils well simulated a change of a paramagnetic signal of soil organic radicals interacted with SDZ. After their application to soil, SL were found in soil sites characterized

  4. Spectroscopic Evidence for Covalent Binding of Sulfadiazine to Natural Soils via 1,4-nucleophilic addition (Michael Type Addition) studied by Spin Labeling ESR

    NASA Astrophysics Data System (ADS)

    Aleksandrova, Olga

    2015-04-01

    Among different classes of veterinary pharmaceuticals, Sulfadiazine (SDZ) is widely used in animal husbandry. Its residues were detected in different environmental compartments. However, soil is a hot spot for SDZ as it receives a large portion of excreted compounds through the application of manure during soil fertilization. Ample studies on the fate of SDZ in soils showed that a large portion forms nonextractable residues (NER) along with transformation products and a low mineralization (Mueller et al., 2013). A common observation was an initially fast formation of NER up to 10% of the applied amount promptly after the application of SDZ to soil, and this portion increased up to 50% within a few days (Mueller et al., 2013; Nowak et al., 2011). A common finding for SDZ, as for other sulfonamides, was biphasic kinetics of the formation of NER, which was attributed to the occurrence of two reaction processes: a rapid, often reversible process and a slower, irreversible process (Weber et al., 1996). A single-phase reaction process was also established under anaerobic treatment (Gulkowska et al., 2014). A major focus of this work is to elucidate a reaction mechanism of covalent binding of SDZ to soil that is currently required to estimate a risk of NER formed by SDZ in soils for human health. Taking into account a key role of the amine functional groups of SDZ on its reactivity in soil, nitroxide radicals with the sewed aromatic or aliphatic amines labeled soil samples and then, were investigated by means of ESR spectroscopy. 2,5,5-Trimethyl-2-(3-aminophenyl)pyrrolidin-1-yloxy and 4-amino-2,2,6,6-Tetramethylpiperidin-1-oxyl modeled decomposition products of SDZ with the aromatic and aliphatic amines, respectively. The application of the defined combination of both spin labels (SL) to different soils well simulated a change of a paramagnetic signal of soil organic radicals interacted with SDZ. After their application to soil, SL were found in soil sites characterized

  5. Effects of the colour additive caramel colour III on the immune system: a study with human volunteers.

    PubMed

    Houben, G F; Abma, P M; van den Berg, H; van Dokkum, W; van Loveren, H; Penninks, A H; Seinen, W; Spanhaak, S; Vos, J G; Ockhuizen, T

    1992-09-01

    Administration of the colour additive Caramel Colour III to rats has been associated with decreased numbers of lymphocytes and several other changes in the immune system, as well as in immune function parameters, specifically in animals fed a diet with a relatively low vitamin B6 content. The effects are caused by the imidazole derivative 2-acetyl-4(5)-tetrahydroxybutylimidazole (THI). Caramel Colour III is commonly used in food products such as bakery products, soya-bean sauces, brown sauces, gravies, soup aromas, brown (dehydrated) soups, brown malt caramel blend for various applications, vinegars and beers, and effects in humans on dietary intake cannot be excluded. Elderly male volunteers with a marginal deficit in vitamin B6 were considered a relevant and potentially sensitive group to study possible effects of Caramel Colour III on blood lymphocyte numbers (total and within subsets) or on proliferative responses of lymphocytes to mitogenic stimulation. In addition, several other haematological parameters, as well as serum immunoglobulin levels and immunoglobulin production in vitro by pokeweed mitogen-stimulated mononuclear blood cells were studied. The results of this double-blind intervention study demonstrated that in a selected test group of apparently healthy elderly male volunteers with a biochemically marginally deficient vitamin B6 status, Caramel Colour III containing 23 (commercial sample) or 143 (research sample) ppm THI and administered at the level of the current acceptable daily intake of 200 mg/kg body weight/day for 7 days did not affect any of the factors investigated. PMID:1427513

  6. A study on the effect of the polymeric additive HPMC on morphology and polymorphism of ortho-aminobenzoic acid crystals

    NASA Astrophysics Data System (ADS)

    Simone, E.; Cenzato, M. V.; Nagy, Z. K.

    2016-07-01

    In the present study, the effect of Hydroxy Propyl Methyl Cellulose (HPMC) on the crystallization of ortho-aminobenzoic acid (OABA) was investigated by seeded and unseeded cooling crystallization experiments. The influence of HPMC on the induction time, crystal shape of Forms I and II of OABA and the polymorphic transformation time was studied. Furthermore, the capability of HPMC to inhibit growth of Form I was evaluated quantitatively and modeled using population balance equations (PBE) solved with the method of moments. The additive was found to strongly inhibit nucleation and growth of Form I as well as to increase the time for the polymorphic transformation from Form II to I. Solvent was also found to influence the shape of Form I crystals at equal concentrations of HPMC. In situ process analytical technology (PAT) tools, including Raman spectroscopy, focused beam reflectance measurement (FBRM) and attenuated total reflectance (ATR) UV-vis spectroscopy were used in combination with off-line techniques, such as optical microscopy, scanning electron microscopy (SEM), Raman spectroscopy, Malvern Mastersizer and differential scanning calorimetry (DSC) to study the crystals produced. The results illustrate how shape, size and stability of the two polymorphs of OABA can be controlled and tailored using a polymeric additive.

  7. Experimental Study of Disruption of Columnar Grains During Rapid Solidification in Additive Manufacturing

    NASA Astrophysics Data System (ADS)

    Manogharan, Guha; Yelamanchi, Bharat; Aman, Ronald; Mahbooba, Zaynab

    2016-03-01

    Over the years, many studies have been conducted to study and analyze the grain structures of metal alloys during additive manufacturing to improve mechanical properties. In particular, columnar grains are observed predominantly during rapid solidification of molten metal. This leads to lower mechanical properties and requires expensive secondary heat-treatment processes. This study is aimed at disrupting the formation of columnar grain growth during rapid solidification using ultrasonic vibration and analyzes the effects on grain structure and mechanical properties. A gas-metal arc welder mounted on a Rep-Rap-based low-cost metal 3 Dimension printer was used to deposit ER70S-6 mild steel layers on a plate. A contact-type ultrasonic transducer with a control system to vary the frequency and power of the vibration was used. The effects of ultrasonic vibration were determined from the statistical analysis of microstructure and micro-indentation techniques on the deposited layer and heat-affected zone. It was found that both frequency and interaction between frequency and power had significant impact on the refinement of average grain size up to 10.64% and increased the number of grains by approximately 41.78%. Analysis of micro-indentation tests showed that there was an increase of approximately 14.30% in micro-hardness due to the applied frequency during rapid solidification. A pole diagram shows that application of vibration causes randomization of grain orientation. Along with the results from this study, further efforts in modeling and experimentation of multi-directional vibrations would lead to a better understanding of disrupting columnar grains in applications that use mechanical vibrations, such as welding, directed energy deposition, brazing, etc.

  8. Percutaneous Dorsal Instrumentation of Vertebral Burst Fractures: Value of Additional Percutaneous Intravertebral Reposition—Cadaver Study

    PubMed Central

    Krüger, Antonio; Schmuck, Maya; Noriega, David C.; Ruchholtz, Steffen; Baroud, Gamal; Oberkircher, Ludwig

    2015-01-01

    Purpose. The treatment of vertebral burst fractures is still controversial. The aim of the study is to evaluate the purpose of additional percutaneous intravertebral reduction when combined with dorsal instrumentation. Methods. In this biomechanical cadaver study twenty-eight spine segments (T11-L3) were used (male donors, mean age 64.9 ± 6.5 years). Burst fractures of L1 were generated using a standardised protocol. After fracture all spines were allocated to four similar groups and randomised according to surgical techniques (posterior instrumentation; posterior instrumentation + intravertebral reduction device + cement augmentation; posterior instrumentation + intravertebral reduction device without cement; and intravertebral reduction device + cement augmentation). After treatment, 100000 cycles (100–600 N, 3 Hz) were applied using a servohydraulic loading frame. Results. Overall anatomical restoration was better in all groups where the intravertebral reduction device was used (p < 0.05). In particular, it was possible to restore central endplates (p > 0.05). All techniques decreased narrowing of the spinal canal. After loading, clearance could be maintained in all groups fitted with the intravertebral reduction device. Narrowing increased in the group treated with dorsal instrumentation. Conclusions. For height and anatomical restoration, the combination of an intravertebral reduction device with dorsal instrumentation showed significantly better results than sole dorsal instrumentation. PMID:26137481

  9. Mechanistic study of secondary organic aerosol components formed from nucleophilic addition reactions of methacrylic acid epoxide

    NASA Astrophysics Data System (ADS)

    Birdsall, A. W.; Miner, C. R.; Mael, L. E.; Elrod, M. J.

    2014-08-01

    Recently, methacrylic acid epoxide (MAE) has been proposed as a precursor to an important class of isoprene-derived compounds found in secondary organic aerosol (SOA): 2-methylglyceric acid (2-MG) and a set of oligomers, nitric acid esters and sulfuric acid esters related to 2-MG. However, the specific chemical mechanisms by which MAE could form these compounds have not been previously studied. In order to determine the relevance of these processes to atmospheric aerosol, MAE and 2-MG have been synthesized and a series of bulk solution-phase experiments aimed at studying the reactivity of MAE using nuclear magnetic resonance (NMR) spectroscopy have been performed. The present results indicate that the acid-catalyzed MAE reaction is more than 600 times slower than a similar reaction of an important isoprene-derived epoxide, but is still expected to be kinetically feasible in the atmosphere on more acidic SOA. The specific mechanism by which MAE leads to oligomers was identified, and the reactions of MAE with a number of atmospherically relevant nucleophiles were also investigated. Because the nucleophilic strengths of water, sulfate, alcohols (including 2-MG), and acids (including MAE and 2-MG) in their reactions with MAE were found to be of a similar magnitude, it is expected that a diverse variety of MAE + nucleophile product species may be formed on ambient SOA. Thus, the results indicate that epoxide chain reaction oligomerization will be limited by the presence of high concentrations of non-epoxide nucleophiles (such as water); this finding is consistent with previous environmental chamber investigations of the relative humidity-dependence of 2-MG-derived oligomerization processes and suggests that extensive oligomerization may not be likely on ambient SOA because of other competitive MAE reaction mechanisms.

  10. Mechanistic study of secondary organic aerosol components formed from nucleophilic addition reactions of methacrylic acid epoxide

    NASA Astrophysics Data System (ADS)

    Birdsall, A. W.; Miner, C. R.; Mael, L. E.; Elrod, M. J.

    2014-12-01

    Recently, methacrylic acid epoxide (MAE) has been proposed as a precursor to an important class of isoprene-derived compounds found in secondary organic aerosol (SOA): 2-methylglyceric acid (2-MG) and a set of oligomers, nitric acid esters, and sulfuric acid esters related to 2-MG. However, the specific chemical mechanisms by which MAE could form these compounds have not been previously studied with experimental methods. In order to determine the relevance of these processes to atmospheric aerosol, MAE and 2-MG have been synthesized and a series of bulk solution-phase experiments aimed at studying the reactivity of MAE using nuclear magnetic resonance (NMR) spectroscopy have been performed. The present results indicate that the acid-catalyzed MAE reaction is more than 600 times slower than a similar reaction of an important isoprene-derived epoxide, but is still expected to be kinetically feasible in the atmosphere on more acidic SOA. The specific mechanism by which MAE leads to oligomers was identified, and the reactions of MAE with a number of atmospherically relevant nucleophiles were also investigated. Because the nucleophilic strengths of water, sulfate, alcohols (including 2-MG), and acids (including MAE and 2-MG) in their reactions with MAE were found to be of similar magnitudes, it is expected that a diverse variety of MAE + nucleophile product species may be formed on ambient SOA. Thus, the results indicate that epoxide chain reaction oligomerization will be limited by the presence of high concentrations of non-epoxide nucleophiles (such as water); this finding is consistent with previous environmental chamber investigations of the relative humidity dependence of 2-MG-derived oligomerization processes and suggests that extensive oligomerization may not be likely on ambient SOA because of other competitive MAE reaction mechanisms.

  11. Study of sorption of two sulfonylurea type of herbicides and their additives on soils and soil components.

    PubMed

    Földényi, Rita; Tóth, Zoltán; Samu, Gyöngyi; Érsek, Csaba

    2013-01-01

    The sorption of two sulfonylurea type herbicides (chlorsulfuron: (1-(2-chlorophenylsulfonyl)-3-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)urea; tribenuron methyl: (methyl-2-[N-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)-3-(methyl-ureido)-sulfonyl]-benzoate) was studied on sand and chernozem soil adsorbents. Experimental results for solutions prepared from the pure ingredients were compared to those prepared from the appropriate formulated commercial products. At small concentrations, the extent of adsorption of the active ingredient was higher than from the formulation containing solutions. Environmental fate and effects of the forming agents are less investigated because they rarely have concentration limits recommended by authorities. In addition to the adsorption of active ingredients, therefore, the sorption behavior of a widely used additive Supragil WP (sodium diisopropyl naphthalene sulphonate) was also studied. This dispersant is an anionic forming agent applied in a lot of pesticide formulations. Using three different soils (sand, brown forest, chernozem) as adsorbents two-step isotherms were obtained. The role of the soil organic matter (OM) was significant in the adsorption mechanism because the adsorbed amounts of the dispersant correlated with the specific surface area as well as with the total organic carbon (TOC) content of the soils. The sorption behavior indicates the operation of hydrophobic interaction mechanism between the soil OM and the dispersant. These results are supported by our further sorption experiments on clays, too. Zeta potential measurements seem to be promising for the interpretation of multi-step isotherms. The application of this technique proved that higher concentrations of the anionic forming agent assisted the peptization of soil organic matter (SOM) resulting in stable colloidal solution dominated by negative charges. Since the pesticides investigated are also anionic at the studied pH (7 and 8.3) the dissolved organics lead to the

  12. Using laser diagnostics for studying the injection of a dry additive

    NASA Astrophysics Data System (ADS)

    Tokunov, Iu. M.; Zhilin, V. G.; Liuliukin, V. I.; Mostinskii, I. L.; Putin, Iu. A.

    1987-02-01

    In MHD generators using an ionizing additive, the uniform injection of the additive into the combustion chamber and the dispersity of the injected particles are important. Some of the problems associated with the injection of an ionizing additive can be alleviated by using dry additives. In the experiment reported here, an He-Ne laser was used to monitor the injection of potash powder with an average size of 40 microns. It is shown that laser diagnostics can be successfully used to determine the mean particle diameter and variation of the powder flow rate with time.

  13. Evaluation of additional head of biceps brachii: a study with autopsy material.

    PubMed

    Ballesteros, L E; Forero, P L; Buitrago, E R

    2014-05-01

    Additional head of the biceps brachii (AHBB) has been reported in different population groups with a frequency of 1-25%. The purpose of this study was to determine the incidence and morphologic expression of the AHBB as determined in a sample of the Colombian population. An exploration was conducted with 106 arms corresponding to unclaimed corpses autopsied at Institute of Legal and Forensic Medicine of Bucaramanga, Colombia. Using medial incision involvingskin, subcutaneous tissue, and brachial fascia, the heads of the biceps and their innervating branches were visualised. One AHBB was observed in 21 (19.8%) of the arms evaluated, with non-significant difference (p = 0.568) per side of presentation: 11 (52.4%) cases on the right side and 10 (47.6%) on the left side. All AHBBs were originated in the infero-medial segment of the humerus, with a mean thickness of 17.8 ± 6.8 mm. In 4 (19%) cases the fascicle was thin, less than 10 mm; in 7 (33.3%) cases it was of medium thickness, between 11 and 20 mm, whereas in 47.6% it was longer than 20 mm. The length of the AHBB was 118.3 ± 26.8 mm; its motor point supplied by the musculocutaneous nerve was located at 101.3 ± 20.9 mm of the bi-epicondylar line. The incidence of AHBB in this study is located at the upper segment of what has been reportedin the literature and could be a morphologic trait of the Colombian population; in agreement with prior studies, the origin was the infero-medial surface of the humerus. PMID:24902098

  14. Increased Risk of Additional Cancers Among Patients with Gastrointestinal Stromal Tumors: A Population-Based Study

    PubMed Central

    Murphy, James D.; Ma, Grace L.; Baumgartner, Joel M.; Madlensky, Lisa; Burgoyne, Adam M.; Tang, Chih-Min; Martinez, Maria Elena; Sicklick, Jason K.

    2015-01-01

    Purpose Most gastrointestinal stromal tumors (GIST) are considered non-hereditary or sporadic. However, single-institution studies suggest that GIST patients develop additional malignancies with increased frequencies. We hypothesized that we could gain greater insight into possible associations between GIST and other malignancies using a national cancer database inquiry. Methods Patients diagnosed with GIST (2001–2011) in the Surveillance, Epidemiology, and End Results database were included. Standardized prevalence ratios (SPRs) and standardized incidence ratios (SIRs) were used to quantify cancer risks incurred by GIST patients before and after GIST diagnoses, respectively, when compared with the general U.S. population. Results Of 6,112 GIST patients, 1,047 (17.1%) had additional cancers. There were significant increases in overall cancer rates: 44% (SPR=1.44) before diagnosis and 66% (SIR=1.66) after GIST diagnoses. Malignancies with significantly increased occurrence both before/after diagnoses included other sarcomas (SPR=5.24/SIR=4.02), neuroendocrine-carcinoid tumors (SPR=3.56/SIR=4.79), non-Hodgkin’s lymphoma (SPR=1.69/SIR=1.76), and colorectal adenocarcinoma (SPR=1.51/SIR=2.16). Esophageal adenocarcinoma (SPR=12.0), bladder adenocarcinoma (SPR=7.51), melanoma (SPR=1.46), and prostate adenocarcinoma (SPR=1.20) were significantly more common only before GIST. Ovarian carcinoma (SIR=8.72), small intestine adenocarcinoma (SIR=5.89), papillary thyroid cancer (SIR=5.16), renal cell carcinoma (SIR=4.46), hepatobiliary adenocarcinomas (SIR=3.10), gastric adenocarcinoma (SIR=2.70), pancreatic adenocarcinoma (SIR=2.03), uterine adenocarcinoma (SIR=1.96), non-small cell lung cancer (SIR=1.74), and transitional cell carcinoma of the bladder (SIR=1.65) were significantly more common only after GIST. Conclusion This is the first population-based study to characterize the associations and temporal relationships between GIST and other cancers, both by site and

  15. A fundamental study of the oxidation behavior of SI primary reference fuels with propionaldehyde and DTBP as an additive

    NASA Astrophysics Data System (ADS)

    Johnson, Rodney

    In an effort to combine the benefits of SI and CI engines, Homogeneous Charge Compression Ignition (HCCI) engines are being developed. HCCI combustion is achieved by controlling the temperature, pressure, and composition of the fuel and air mixture so that autoignition occurs in proper phasing with the piston motion. This control system is fundamentally more challenging than using a spark plug or fuel injector to determine ignition timing as in SI and CI engines, respectively. As a result, this is a technical barrier that must be overcome to make HCCI engines applicable to a wide range of vehicles and viable for high volume production. One way to tailor the autoignition timing is to use small amounts of ignition enhancing additives. In this study, the effect of the addition of DTBP and propionaldehyde on the autoignition behavior of SI primary reference fuels was investigated. The present work was conducted in a new research facility built around a single cylinder Cooperative Fuels Research (CFR) octane rating engine but modified to run in HCCI mode. It focused on the effect of select oxygenated hydrocarbons on hydrocarbon fuel oxidation, specifically, the primary reference fuels n-heptane and iso-octane. This work was conducted under HCCI operating conditions. Previously, the operating parameters for this engine were validated for stable combustion under a wide range of operating parameters such as engine speeds, equivalence ratios, compression ratios and inlet manifold temperature. The stable operating range under these conditions was recorded and used for the present study. The major focus of this study was to examine the effect of the addition of DTBP or propionaldehyde on the oxidation behavior of SI primary reference fuels. Under every test condition the addition of the additives DTBP and propionaldehyde caused a change in fuel oxidation. DTBP always promoted fuel oxidation while propionaldehyde promoted oxidation for lower octane number fuels and delayed

  16. A SEARCH FOR ADDITIONAL PLANETS IN FIVE OF THE EXOPLANETARY SYSTEMS STUDIED BY THE NASA EPOXI MISSION

    SciTech Connect

    Ballard, Sarah; Charbonneau, David; Holman, Matthew J.; Christiansen, Jessie L.; Deming, Drake; Barry, Richard K.; Kuchner, Marc J.; Livengood, Timothy A.; Hewagama, Tilak; Hampton, Don L.; Lisse, Carey M.; Seager, Sara; Veverka, Joseph F.

    2011-05-01

    We present time series photometry and constraints on additional planets in five of the exoplanetary systems studied by the EPOCh (Extrasolar Planet Observation and Characterization) component of the NASA EPOXI mission: HAT-P-4, TrES-3, TrES-2, WASP-3, and HAT-P-7. We conduct a search of the high-precision time series for photometric transits of additional planets. We find no candidate transits with significance higher than our detection limit. From Monte Carlo tests of the time series using putative periods from 0.5 days to 7 days, we demonstrate the sensitivity to detect Neptune-sized companions around TrES-2, sub-Saturn-sized companions in the HAT-P-4, TrES-3, and WASP-3 systems, and Saturn-sized companions around HAT-P-7. We investigate in particular our sensitivity to additional transits in the dynamically favorable 3:2 and 2:1 exterior resonances with the known exoplanets: if we assume coplanar orbits with the known planets, then companions in these resonances with HAT-P-4b, WASP-3b, and HAT-P-7b would be expected to transit, and we can set lower limits on the radii of companions in these systems. In the nearly grazing exoplanetary systems TrES-3 and TrES-2, additional coplanar planets in these resonances are not expected to transit. However, we place lower limits on the radii of companions that would transit if the orbits were misaligned by 2.{sup 0}0 and 1.{sup 0}4 for TrES-3 and TrES-2, respectively.

  17. Investigation of mercury transformation by HBr addition in a slipstream facility with real flue gas atmospheres of bituminous coal and Powder River Basin Coal

    SciTech Connect

    Yan Cao; Quanhai Wang; Chien-wei Chen; Bobby Chen; Martin Cohron; Yi-chuan Tseng; Cheng-chung Chiu; Paul Chu; Wei-Ping Pan

    2007-09-15

    An investigation of speciated mercury transformation with the addition of hydrogen bromide (HBr) at elevated temperatures was conducted in a slipstream reactor with real flue gas atmospheres. Test results indicated that adding HBr into the flue gas at several parts per million strongly impacted the mercury oxidation and adsorption, which were dependent upon temperature ranges. Higher temperatures (in the range of 300-350 C) promoted mercury oxidation by HBr addition but did not promote mercury adsorption. Lower temperatures (in a range of 150-200 C) enhanced mercury adsorption on the fly ash by adding HBr. Test results also verified effects of flue gas atmospheres on the mercury oxidation by the addition of HBr, which included concentrations of chlorine and sulfur in the flue gas. Chlorine species seemed to be involved in the competition with bromine species in the mercury oxidation process. With the addition of HBr at 3 ppm at a temperature of about 330 C, the additional mercury oxidation could be reached by about 55% in a flue gas atmosphere by burning PRB coal in the flue gas and by about 20% in a flue gas by burning bituminous coal. These are both greater than the maximum gaseous HgBr2 percentage in the flue gas (35% for PRB coal and 5% for bituminous coal) by thermodynamic equilibrium analysis predictions under the same conditions. This disagreement may indicate a greater complexity of mercury oxidation mechanisms by the addition of HBr. It is possible that bromine species promote activated chlorine species generation in the flue gas, where the kinetics of elemental mercury oxidation were enhanced. However, SO{sub 2} in the flue gas may involve the consumption of the available activated chlorine species. Thus, the higher mercury oxidation rate by adding bromine under the flue gas by burning PRB coal may be associated with its lower SO{sub 2} concentration in the flue gas. 39 refs., 8 figs., 4 tabs.

  18. Additional Language Teaching within the International Baccalaureate Primary Years Programme: A Comparative Study

    ERIC Educational Resources Information Center

    Lebreton, Marlène

    2014-01-01

    The International Baccalaureate Primary Years Programme supports the learning of languages and cultures, but the role of the additional language within this programme is often unclear. There remains a great variability in schools regarding the frequency of lessons and the way that the additional language is taught within the Primary Years…

  19. Beyond the Call of Duty: A Qualitative Study of Teachers' Additional Responsibilities Related to Sexuality Education

    ERIC Educational Resources Information Center

    Eisenberg, Marla E.; Madsen, Nikki; Oliphant, Jennifer A.; Resnick, Michael

    2011-01-01

    Seven focus groups were conducted with sexuality educators in Minnesota to explore ways that teaching sexuality education differs from teaching other health education content and to determine if additional supports or resources are needed for sexuality educators. Teachers described many specific additional responsibilities or concerns related to…

  20. A theoretical study of wave dispersion and thermal conduction for HMX/additive interfaces

    NASA Astrophysics Data System (ADS)

    Long, Yao; Chen, Jun

    2014-04-01

    The wave dispersion rule for non-uniform material is useful for ultrasonic inspection and engine life prediction, and also is key in achieving an understanding of the energy dissipation and thermal conduction properties of solid material. On the basis of linear response theory and molecular dynamics, we derive a set of formulas for calculating the wave dispersion rate of interface systems, and study four kinds of interfaces inside plastic bonded explosives: HMX/{HMX, TATB, F2312, F2313}. (HMX: octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine; TATB: 1,3,5-triamino-2,4,6-trinitrobenzene; F2312, F2313: fluoropolymers). The wave dispersion rate is obtained over a wide frequency range from kHz to PHz. We find that at low frequency, the rate is proportional to the square of the frequency, and at high frequency, the rate couples with the molecular vibration modes at the interface. By using the results, the thermal conductivities of HMX/additive interfaces are derived, and a physical model is built for describing the total thermal conductivity of mixture explosives, including HMX multi-particle systems and {TATB, F2312, F2313}-coated HMX.

  1. Ecological Optimization and Parametric Study of an Irreversible Regenerative Modified Brayton Cycle with Isothermal Heat Addition

    NASA Astrophysics Data System (ADS)

    Tyagi, Sudhir K.; Kaushik, Subhash C.; Tiwari, Vivek

    2003-12-01

    An ecological optimization along with a detailed parametric study of an irreversible regenerative Brayton heat engine with isothermal heat addition have been carried out with external as well as internal irreversibilities. The ecological function is defined as the power output minus the power loss (irreversibility) which is ambient temperature times the entropy generation rate. The external irreversibility is due to finite temperature difference between the heat engine and the external reservoirs while the internal irreversibilities are due to nonisentropic compression and expansion processes in the compressor and the turbine respectively and the regenerative heat loss. The ecological function is found to be an increasing function of the isothermal-, sink- and regenerative-side effectiveness, isothermal-side inlet temperature, component efficiencies and sink-side temperature while it is found to be a decreasing function of the isobaric-side temperature and effectiveness and the working fluid heat capacitance rate. The effects of the isobaric-side effectiveness are found to be more than those of the other parameters and the effects of turbine efficiency are found to be more than those of the compressor efficiency on all the performance parameters of the cycle.

  2. Theoretical study of addition reactions of carbene, silylene, and germylene to carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Chu, Ying-Ying; Su, Ming-Der

    2004-08-01

    A theoretical study of the mechanism of the reaction of a single-walled carbon nanotube (SWCNT) with carbene (H 2C), silylene (H 2Si), and germylene (H 2Ge) has been carried out using a two-layered ONIOM(B3LYP/6-311G ∗:PM3) approach. The main findings are as follows: (1) The computational results based on the method used in this work are in good agreement with recent theoretical findings [Angew. Chem. Int. Ed. 41 (2002) 1853]. That is, SWCNTs with H 2C, H 2Si, and H 2Ge addends favor opened structures rather than three-membered rings. (2) The greater the atomic number of the carbene center, the larger the activation energy and the less exothermic (or the more endothermic) the cycloaddition reaction becomes. Therefore, addition to the C dbnd C bond of a SWCNT is more difficult the heavier the carbene center. (3) The theoretical observations suggest that the singlet-triplet splitting of a carbene can be used as a guide to its reactivity during the SWCNT cycloaddition process.

  3. An Investigation of the Feasibility of Obtaining Additional Subscores on the GRE Advanced Psychology Test. GRE Board Professional Report GREB No. 74-4P.

    ERIC Educational Resources Information Center

    McPeek, Miles; And Others

    This study was undertaken to determine whether additional information useful for guidance or placement could be derived from the existing Graduate Record Examinations (GRE) Advanced Psychology Test. The number of subscores currently reported is limited by the high reliability required to make admissions decisions; subscores used only for guidance…

  4. Study on the performance of polycarboxylate-based superplasticizers synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization

    NASA Astrophysics Data System (ADS)

    Yu, Binbin; Zeng, Zhong; Ren, Qinyu; Chen, Yang; Liang, Mei; Zou, Huawei

    2016-09-01

    A series of block type polycarboxylate-based superplasticizers (PCs) with different molecular architectures were synthesized with macromonomer butenyl alkylene polyoxyethylene-polyoxypropylene ether (BAPP) and acrylic acid (AA) by reversible addition-fragmentation chain transfer (RAFT) polymerization. Fourier-Transformed Infrared (FTIR) Spectroscopy and dynamic light scattering (DLS) were applied to investigate the PCs' molecular structure. The dispersion capacity of the PCs in cement were also measured, and the results showed that the polycarboxylic dispersing agents prepared by this method were suitable for portlant cement. It was found that the PCs could affect the hydration process, which was performed through retarding the generation of ettringite in the hydrated product. Our studies with X-ray diffraction (XRD), scanning electron microscopy (SEM) and compressive strength measurement of hydrated production were all supporting this conclusion.

  5. Additional weight load increases freezing of gait episodes in Parkinson's disease; an experimental study.

    PubMed

    Mensink, Senja H G; Nonnekes, Jorik; van Bon, Geert; Snijders, Anke H; Duysens, Jacques; Weerdesteyn, Vivian; Bloem, Bastiaan R; Oude Nijhuis, Lars B

    2014-05-01

    Freezing of gait is an episodic gait disorder,characterized by the inability to generate effective forward stepping movements. The pathophysiology underlying freezing of gait remains insufficiently understood, and this hampers the development of better treatment strategies.Preliminary evidence suggests that impaired force control during walking may contribute to freezing episodes, with difficulty to unload the swing leg and initiate the swing phase. Here, we used external loading to manipulate force control and to investigate its influence on freezing of gait.Twelve Parkinson's disease patients with freezing of gait performed three contrasting tasks: (1) loaded gait while wearing a belt fortified with lead weights; (2) weight supported gait using a parachute harness connected to a rigid metal cable running above the gait trajectory; and (3)normal gait. Gait tasks were used to provoke freezing episodes, including rapid 360° turns. Freezing episodes were quantified using blinded, videotaped clinical assessment. Furthermore, ground reaction forces and body kinematics were recorded. Loading significantly increased the mean number of freezing episodes per trial compared to the normal gait condition (P<0.05), but the effect of weight support was not consistent. Loading particularly increased the number of freezing episodes during rapid short steps. Step length was significantly smaller during loaded gait compared to normal gait (P<0.05), but changes in anticipatory postural adjustments were not different.Our results may point to impaired force control playing a key role in freezing of gait. Future studies should further investigate the mechanism, i.e., the contribution of deficient load feedback, and evaluate which forms of weight support might offer treatment opportunities. PMID:24658705

  6. Food additives.

    PubMed

    Berglund, F

    1978-01-01

    The use of additives to food fulfils many purposes, as shown by the index issued by the Codex Committee on Food Additives: Acids, bases and salts; Preservatives, Antioxidants and antioxidant synergists; Anticaking agents; Colours; Emulfifiers; Thickening agents; Flour-treatment agents; Extraction solvents; Carrier solvents; Flavours (synthetic); Flavour enhancers; Non-nutritive sweeteners; Processing aids; Enzyme preparations. Many additives occur naturally in foods, but this does not exclude toxicity at higher levels. Some food additives are nutrients, or even essential nutritents, e.g. NaCl. Examples are known of food additives causing toxicity in man even when used according to regulations, e.g. cobalt in beer. In other instances, poisoning has been due to carry-over, e.g. by nitrate in cheese whey - when used for artificial feed for infants. Poisonings also occur as the result of the permitted substance being added at too high levels, by accident or carelessness, e.g. nitrite in fish. Finally, there are examples of hypersensitivity to food additives, e.g. to tartrazine and other food colours. The toxicological evaluation, based on animal feeding studies, may be complicated by impurities, e.g. orthotoluene-sulfonamide in saccharin; by transformation or disappearance of the additive in food processing in storage, e.g. bisulfite in raisins; by reaction products with food constituents, e.g. formation of ethylurethane from diethyl pyrocarbonate; by metabolic transformation products, e.g. formation in the gut of cyclohexylamine from cyclamate. Metabolic end products may differ in experimental animals and in man: guanylic acid and inosinic acid are metabolized to allantoin in the rat but to uric acid in man. The magnitude of the safety margin in man of the Acceptable Daily Intake (ADI) is not identical to the "safety factor" used when calculating the ADI. The symptoms of Chinese Restaurant Syndrome, although not hazardous, furthermore illustrate that the whole ADI

  7. Investigation of habit changes of alum crystals, KAl(SO 4) 2·12 H 2O, by novel additives to the nutrient

    NASA Astrophysics Data System (ADS)

    Bolanz, Gerald; Schäfer, Otto

    1986-12-01

    The effect of new additives on the change in habit of alum crystal (from octahedron to cube) was investigated. Compounds related to 3,4,5-trihydroxy-benzoic acid (gallic acid) lead to this change in habit if the distances between the three phenolic groups and the carbonyl group are directly matched to the positions of the two K + and the two Al 3+ ions on the (100) plane. Among various surfactants, only sulfonic acids with chain lengths of 10 or 12 C atoms affect the crystal habit. The sulfuric acid esters were ineffective. Quantitative data on the growth kinetics have been obtained.

  8. Fortification of yogurts with different antioxidant preservatives: A comparative study between natural and synthetic additives.

    PubMed

    Caleja, Cristina; Barros, Lillian; Antonio, Amilcar L; Carocho, Márcio; Oliveira, M Beatriz P P; Ferreira, Isabel C F R

    2016-11-01

    Consumers demand more and more so-called "natural" products and, therefore, the aim of this work was to compare the effects of natural versus synthetic antioxidant preservatives in yogurts. Matricaria recutita L. (chamomile) and Foeniculum vulgare Mill. (fennel) decoctions were tested as natural additives, while potassium sorbate (E202) was used as a synthetic additive. The fortification of yogurts with natural and synthetic antioxidants did not cause significant changes in the yoghurt pH and nutritional value, in comparison with control samples (yogurt without any additive). However, the fortified yogurts showed higher antioxidant activity, mainly the yogurts with natural additives (and among these, the ones with chamomile decoction). Overall, it can be concluded that plant decoctions can be used to develop novel yogurts, by replacing synthetic preservatives and improving the antioxidant properties of the final product, without changing the nutritional profile. PMID:27211646

  9. Investigating the addition of SiO₂-CaO-ZnO-Na₂O-TiO₂ bioactive glass to hydroxyapatite: Characterization, mechanical properties and bioactivity.

    PubMed

    Yatongchai, Chokchai; Placek, Lana M; Curran, Declan J; Towler, Mark R; Wren, Anthony W

    2015-11-01

    Hydroxyapatite (Ca10(PO4)6(OH)2) is widely investigated as an implantable material for hard tissue restoration due to its osteoconductive properties. However, hydroxyapatite in bulk form is limited as its mechanical properties are insufficient for load-bearing orthopedic applications. Attempts have been made to improve the mechanical properties of hydroxyapatite, by incorporating ceramic fillers, but the resultant composite materials require high sintering temperatures to facilitate densification, leading to the decomposition of hydroxyapatite into tricalcium phosphate, tetra-calcium phosphate and CaO phases. One method of improving the properties of hydroxyapatite is to incorporate bioactive glass particles as a second phase. These typically have lower softening points which could possibly facilitate sintering at lower temperatures. In this work, a bioactive glass (SiO2-CaO-ZnO-Na2O-TiO2) is incorporated (10, 20 and 30 wt%) into hydroxyapatite as a reinforcing phase. X-ray diffraction confirmed that no additional phases (other than hydroxyapatite) were formed at a sintering temperature of 560 ℃ with up to 30 wt% glass addition. The addition of the glass phase increased the % crystallinity and the relative density of the composites. The biaxial flexural strength increased to 36 MPa with glass addition, and there was no significant change in hardness as a function of maturation. The pH of the incubation media increased to pH 10 or 11 through glass addition, and ion release profiles determined that Si, Na and P were released from the composites. Calcium phosphate precipitation was encouraged in simulated body fluid with the incorporation of the bioactive glass phase, and cell culture testing in MC-3T3 osteoblasts determined that the composite materials did not significantly reduce cell viability. PMID:26116020

  10. ALUM ADDITION AND STEP-FEED STUDIES IN OXYGEN-ACTIVATED SLUDGE

    EPA Science Inventory

    A plug flow, O2-activated sludge process was operated with alum addition to remove phosphorus and with lime addition to prevent the process pH from decreasing below 6.4. The O2 reactor was operated at F/M ratios between 0.18 to 0.24 gm of BOD5/gm of MLVSS/day in a typical co-curr...

  11. Chemostat Studies of TCE-Dehalogenating Anaerobic Consortia under Excess and Limited Electron Donor Addition

    NASA Astrophysics Data System (ADS)

    Semprini, L.; Azizian, M.; Green, J.; Mayer-Blackwell, K.; Spormann, A. M.

    2015-12-01

    Two cultures - the Victoria Strain (VS) and the Evanite Strain (EV), enriched with the organohalide respiring bacteria Dehalococcoides mccartyi - were grown in chemostats for more than 4 years at a mean cell residence time of 50 days. The slow doubling rate represents growth likely experienced in the subsurface. The chemostats were fed formate as an electron donor and trichloroethene (TCE) as the terminal electron acceptor. Under excess formate conditions, stable operation was observed with respect to TCE transformation, steady-state hydrogen (H2) concentrations (40 nM), and the structure of the dehalogenating community. Both cultures completely transformed TCE to ethene, with minor amounts of vinyl chloride (VC) observed, along with acetate formation. When formate was limited, TCE was transformed incompletely to ethene (40-60%) and VC (60- 40%), and H2 concentrations ranged from 1 to 3 nM. The acetate concentration dropped below detection. Batch kinetic studies of TCE transformation with chemostat harvested cells found transformation rates of c-DCE and VC were greatly reduced when the cells were grown with limited formate. Upon increasing formate addition to the chemostats, from limited to excess, essentially complete transformation of TCE to ethene was achieved. The increase in formate was associated with an increase in H2 concentration and the production of acetate. Results of batch kinetic tests showed increases in transformation rates for TCE and c-DCE by factors of 3.5 and 2.5, respectively, while VC rates increased by factors of 33 to 500, over a six month period. Molecular analysis of chemostat samples is being performed to quantify the changes in copy numbers of reductase genes and to determine whether shifts in the strains of Dehalococcoides mccartyi where responsible for the observed rate increases. The results demonstrate the importance of electron donor supply for successful in-situ remediation.

  12. Biological effect of food additive titanium dioxide nanoparticles on intestine: an in vitro study.

    PubMed

    Song, Zheng-Mei; Chen, Ni; Liu, Jia-Hui; Tang, Huan; Deng, Xiaoyong; Xi, Wen-Song; Han, Kai; Cao, Aoneng; Liu, Yuanfang; Wang, Haifang

    2015-10-01

    Titanium dioxide nanoparticles (TiO2 NPs) are widely found in food-related consumer products. Understanding the effect of TiO2 NPs on the intestinal barrier and absorption is essential and vital for the safety assessment of orally administrated TiO2 NPs. In this study, the cytotoxicity and translocation of two native TiO2 NPs, and these two TiO2 NPs pretreated with the digestion simulation fluid or bovine serum albumin were investigated in undifferentiated Caco-2 cells, differentiated Caco-2 cells and Caco-2 monolayer. TiO2 NPs with a concentration less than 200 µg ml(-1) did not induce any toxicity in differentiated cells and Caco-2 monolayer after 24 h exposure. However, TiO2 NPs pretreated with digestion simulation fluids at 200 µg ml(-1) inhibited the growth of undifferentiated Caco-2 cells. Undifferentiated Caco-2 cells swallowed native TiO2 NPs easily, but not pretreated NPs, implying the protein coating on NPs impeded the cellular uptake. Compared with undifferentiated cells, differentiated ones possessed much lower uptake ability of these TiO2 NPs. Similarly, the traverse of TiO2 NPs through the Caco-2 monolayer was also negligible. Therefore, we infer the possibility of TiO2 NPs traversing through the intestine of animal or human after oral intake is quite low. This study provides valuable information for the risk assessment of TiO2 NPs in food. PMID:26106068

  13. A study of the electrochemistry of nickel hydroxide electrodes with various additives

    NASA Astrophysics Data System (ADS)

    Zhu, Wen-Hua; Ke, Jia-Jun; Yu, Hong-Mei; Zhang, Deng-Jun

    Nickel composite electrodes (NCE) with various additives are prepared by a chemical impregnation method from nitrate solutions on sintered porous plaques. The electrochemical properties, such as utilization of active material, swelling and the discharge potential of the nickel oxide electrode (NOE) are determined mainly through the composition of the active material and the characteristics of nickel plaques. Most additives (Mg, Ca, Sr, Ba, Zn, Cd, Co, Li and Al hydroxide) exert effects on the discharge potential and swelling of the NOE. Chemical co-precipitation with the addition of calcium, zinc, magnesium and barium hydroxide increases the discharge potential by more than 20 mV, but that with zinc hydroxide results in an obvious decrease of active-material utilization and that with calcium and magnesium hydroxide produces a larger increase of electrode thickness. The effects of anion additives are also examined. Less than 1% mol of NiS in the active material increases the discharge potential. Cadmium, cobalt and zinc hydroxide are excellent additives for preventing swelling of the NCE. Slow voltammetry (0.2 mV s -1) in 6 M KOH is applied to characterize the oxygen-evolving potential of the NCE. The difference between the oxygen-evolution potential and the potential of the oxidation peak for the NCE with additives of calcium, lithium, barium and aluminium hydroxide is at least + 60 mV.

  14. 78 FR 68461 - Guidance for Industry: Studies To Evaluate the Utility of Anti-Salmonella Chemical Food Additives...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-14

    ... Guidance for Industry: Studies to Evaluate the Utility of Anti-Salmonella Chemical Food Additives in Feeds... HUMAN SERVICES Food and Drug Administration Guidance for Industry: Studies To Evaluate the Utility of Anti- Salmonella Chemical Food Additives in Feeds; Request for Comments AGENCY: Food and...

  15. Investigating Sexual Abuse: Findings of a 15-Year Longitudinal Study

    ERIC Educational Resources Information Center

    McCormack, Bob; Kavanagh, Denise; Caffrey, Shay; Power, Anne

    2005-01-01

    Background: There is a lack of longitudinal large-scale studies of sexual abuse in intellectual disability services. Such studies offer opportunities to examine patterns in disclosure, investigation and outcomes, and to report on incidence and trends. Methods: All allegations of sexual abuse (n = 250) involving service users as victims or…

  16. Investigating Science Collaboratively: A Case Study of Group Learning

    ERIC Educational Resources Information Center

    Zinicola, Debra A.

    2009-01-01

    Discussions of one urban middle school group of students who were investigating scientific phenomena were analyzed; this study was conducted to discern if and how peer interaction contributes to learning. Through a social constructivist lens, case study methodology, we examined conceptual change among group members. Data about science talk was…

  17. A Comparative Study of Listening Comprehension Measures in English as an Additional Language and Native English-Speaking Primary School Children

    ERIC Educational Resources Information Center

    McKendry, Mairead Grainne; Murphy, Victoria A.

    2011-01-01

    The aim of this study was to investigate the suitability of different measures of listening comprehension for Years 2, 3 and 4 children with English as an additional language (EAL). Non-standardised uses of reading comprehension measures are often employed as proxy measures of listening comprehension, i.e. for purposes for which they were not…

  18. Additive influence of genetic predisposition and conventional risk factors in the incidence of coronary heart disease: a population-based study in Greece

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An additive genetic risk score (GRS) for coronary heart disease (CHD) has previously been associated with incident CHD in the population-based Greek European Prospective Investigation into Cancer and nutrition (EPIC) cohort. In this study, we explore GRS-‘environment’ joint actions on CHD for severa...

  19. Mechanical characterization of filler sandcretes with rice husk ash additions. Study applied to Senegal

    SciTech Connect

    Cisse, I.K.; Laquerbe, M.

    2000-01-01

    To capitalize on the local materials of Senegal (agricultural and industrial wastes, residual fines from crushing process, sands from dunes, etc.), rise husk ash and residues of industrial and agricultural wastes have been used as additions in sandcretes. The mechanical resistance of sandcrete blocks obtained when unground ash (and notably the ground ash) is added reveals that there is an increase in performance over the classic mortar blocks. In addition, the use of unground rice husk ash enables production of a lightweight sandcrete with insulating properties, at a reduced cost. The ash pozzolanic reactivity explains the high strengths obtained.

  20. In-situ study of the influence of additives on the growth behavior of copper electrodeposits on copper single crystal

    NASA Astrophysics Data System (ADS)

    Wu, Aiwen

    Trace organic additives are known to be essential in obtaining desired metal electrodeposits in the microelectronic industry, however, fundamental design principles for their use and a scientific understanding of their interaction during electrodeposition is lacking. In the present study we investigated electrodeposition of copper on the Cu(100) surface in air-saturated or dearated acid-sulfate plating solutions containing several combinations of chloride and additives benzotriazole (BTA) and 3-mercapto propane sulfonic acid (MPSA) under galvanostatic pulse-current conditions. The electrodeposition process was followed using in-situ atomic force microscopy (AFM). AFM images were quantitatively analyzed by pattern-recognition and scaling procedures. In the absence of additives, copper deposits grew in a layer-by-layer mode from the earliest stage of deposition. The surface consisted of smooth terraces separated by steps. The scaling analysis result was consistent with a process dominated by surface diffusion and step growth. In chloride containing solutions, square-pyramidal mounds were initiated and grew to cover the surface. Mound slope increased with deposition time with no indication of reaching a steady-state value. This growth mode was consistent with a surface diffusion mechanism. The scaling result was similar to the additive-free system, but indicated that surface diffusion was more dominant in the presence of chloride. BTA inhibited the surface and produced nucleation-limited growth at hemispheroidal centers whose height to base radius aspect ratio increased linearly with deposition time. Nucleation and growth of three-dimensional nodules started randomly across the entire surface. The nodules were smaller in size than the mounds observed without BTA. The number and density of nodules were much higher than the mounds density. The deposit growth was dominated by a roughening mechanism that can be described by the random roughening term of a stochastic model

  1. Jason 1 Investigation: Altimetric Studies of Ocean Tidal Dynamics

    NASA Technical Reports Server (NTRS)

    Egbert, Gary D.

    2004-01-01

    Two papers on tidal dissipation were completed and published. The first of these extended our earlier work, which focused on the dominant M2 constituent, to include 7 additional constituents. In addition to confirming a total deep water dissipation total very close to 1 TW, this study demonstrated significant differences in the distribution of dissipation between diurnal and semi-diurnal constituents. The second paper involved an extensive modeling study of tides in the present day and the last glacial maximum. In this study we showed that accuracy of tidal solutions for the present day Ocean were significantly improved by including a parameterization of internal tide drag over rough topography in the deep ocean. It was also demonstrated that a complete self-consistent treatment of Ocean self attraction and tidal loading was required for accurate solutions.

  2. Study on automatic optical element addition or deletion in lens optimization

    NASA Astrophysics Data System (ADS)

    Cheng, Xuemin; Wang, Yongtian; Hao, Qun

    2002-09-01

    Two lens form parameters, quantifying the symmetry of the optical system and the optical power distribution among the individual lens elements, are used as the criteria for automatic element addition or deletion in lens optimization. The scheme based on the criteria is described in this paper. Design examples are provided, which demonstrate that the scheme is practicable.

  3. Teaching Young Children Decomposition Strategies to Solve Addition Problems: An Experimental Study

    ERIC Educational Resources Information Center

    Cheng, Zi-Juan

    2012-01-01

    The ability to count has traditionally been considered an important milestone in children's development of number sense. However, using counting (e.g., counting on, counting all) strategies to solve addition problems is not the best way for children to achieve their full mathematical potential and to prepare them to develop more complex and…

  4. Vector generalized additive models for extreme rainfall data analysis (study case rainfall data in Indramayu)

    NASA Astrophysics Data System (ADS)

    Utami, Eka Putri Nur; Wigena, Aji Hamim; Djuraidah, Anik

    2016-02-01

    Rainfall pattern are good indicators for potential disasters. Global Circulation Model (GCM) contains global scale information that can be used to predict the rainfall data. Statistical downscaling (SD) utilizes the global scale information to make inferences in the local scale. Essentially, SD can be used to predict local scale variables based on global scale variables. SD requires a method to accommodate non linear effects and extreme values. Extreme value Theory (EVT) can be used to analyze the extreme value. One of methods to identify the extreme events is peak over threshold that follows Generalized Pareto Distribution (GPD). The vector generalized additive model (VGAM) is an extension of the generalized additive model. It is able to accommodate linear or nonlinear effects by involving more than one additive predictors. The advantage of VGAM is to handle multi response models. The key idea of VGAM are iteratively reweighted least square for maximum likelihood estimation, penalized smoothing, fisher scoring and additive models. This works aims to analyze extreme rainfall data in Indramayu using VGAM. The results show that the VGAM with GPD is able to predict extreme rainfall data accurately. The prediction in February is very close to the actual value at quantile 75.

  5. Studies on the Food Additive Propyl Gallate: Synthesis, Structural Characterization, and Evaluation of the Antioxidant Activity

    ERIC Educational Resources Information Center

    Garrido, Jorge; Garrido, E. Manuela; Borges, Fernanda

    2012-01-01

    Antioxidants are additives largely used in industry for delaying, retarding, or preventing the development of oxidative deterioration. Propyl gallate (E310) is a phenolic antioxidant extensively used in the food, cosmetics, and pharmaceutical industries. A series of lab experiments have been developed to teach students about the importance and…

  6. Lessons from the TAPS study--managing investigation results--is your practice system safe?

    PubMed

    Makeham, Meredith A B; Bridges-Webb, Charles; Kidd, Michael R

    2008-08-01

    The TAPS study found that errors in the process of providing health care were reported by general practitioners more than twice as often as deficiencies in a clinician's knowledge or skills. Approximately 20% of these process error events concerned investigations. In addition, some reported events that related to investigations included filing system and recall errors, which accounted for a further 10% of reported error events. PMID:18704210

  7. Investigation of Poultry Waste for Anaerobic Digestion: A Case Study

    NASA Astrophysics Data System (ADS)

    Salam, Christopher R.

    Anaerobic Digestion (AD) is a biological conversion technology which is being used to produce bioenergy all over the world. This energy is created from biological feedstocks, and can often use waste products from various food and agricultural processors. Biogas from AD can be used as a fuel for heating or for co-generation of electricity and heat and is a renewable substitute to using fossil fuels. Nutrient recycling and waste reduction are additional benefits, creating a final product that can be used as a fertilizer in addition to energy benefits. This project was conducted to investigate the viability of three turkey production wastes as AD feedstock: two turkey litters and a material separated from the turkey processing wastewater using dissolved air flotation (DAF) process. The DAF waste contained greases, oils and other non-commodity portions of the turkey. Using a variety of different process methods, types of bacteria, loading rates and food-to-microorganism ratios, optimal loading rates for the digestion of these three materials were obtained. In addition, the co-digestion of these materials revealed additional energy benefits. In this study, batch digestion tests were carried out to treat these three feedstocks, using mesophilic and thermophilic bacteria, using loading rates of 3 and 6 gVS/L They were tested separately and also as a mixture for co-digestion. The batch reactor used in this study had total and working volumes of 1130 mL and 500 mL, respectively. The initial organic loading was set to be 3 gVS/L, and the food to microorganism ratio was either 0.6 or 1.0 for different treatments based on the characteristics of each material. Only thermophilic (50 +/- 2ºC) temperatures were tested for the litter and DAF wastes in continuous digestion, but mesophilic and thermophilic batch digestion experiments were conducted. The optimum digestion time for all experiments was 14 days. The biogas yields of top litter, mixed litter, and DAF waste under

  8. Indolyne Experimental and Computational Studies: Synthetic Applications and Origins of Selectivities of Nucleophilic Additions

    PubMed Central

    Im, G-Yoon J.; Bronner, Sarah M.; Goetz, Adam E.; Paton, Robert S.; Cheong, Paul H.-Y.; Houk, K. N.; Garg, Neil K.

    2010-01-01

    Efficient syntheses of 4,5-, 5,6-, and 6,7-indolyne precursors beginning from commercially available hydroxyindole derivatives are reported. The synthetic routes are versatile and allow access to indolyne precursors that remain unsubstituted on the pyrrole ring. Indolynes can be generated under mild fluoride-mediated conditions, trapped by a variety of nucleophilic reagents, and used to access a number of novel substituted indoles. Nucleophilic addition reactions to indolynes proceed with varying degrees of regioselectivity; distortion energies control regioselectivity and provide a simple model to predict the regioselectivity in the nucleophilic additions to indolynes and other unsymmetrical arynes. This model has led to the design of a substituted 4,5-indolyne that exhibits enhanced nucleophilic regioselectivity. PMID:21114321

  9. Structural changes in gluten protein structure after addition of emulsifier. A Raman spectroscopy study

    NASA Astrophysics Data System (ADS)

    Ferrer, Evelina G.; Gómez, Analía V.; Añón, María C.; Puppo, María C.

    2011-06-01

    Food protein product, gluten protein, was chemically modified by varying levels of sodium stearoyl lactylate (SSL); and the extent of modifications (secondary and tertiary structures) of this protein was analyzed by using Raman spectroscopy. Analysis of the Amide I band showed an increase in its intensity mainly after the addition of the 0.25% of SSL to wheat flour to produced modified gluten protein, pointing the formation of a more ordered structure. Side chain vibrations also confirmed the observed changes.

  10. A design study for the addition of higher order parametric discrete elements to NASTRAN

    NASA Technical Reports Server (NTRS)

    Stanton, E. L.

    1972-01-01

    The addition of discrete elements to NASTRAN poses significant interface problems with the level 15.1 assembly modules and geometry modules. Potential problems in designing new modules for higher-order parametric discrete elements are reviewed in both areas. An assembly procedure is suggested that separates grid point degrees of freedom on the basis of admissibility. New geometric input data are described that facilitate the definition of surfaces in parametric space.

  11. Load bearing and stiffness tailored NiTi implants produced by additive manufacturing: a simulation study

    NASA Astrophysics Data System (ADS)

    Rahmanian, Rasool; Shayesteh Moghaddam, Narges; Haberland, Christoph; Dean, David; Miller, Michael; Elahinia, Mohammad

    2014-03-01

    Common metals for stable long-term implants (e.g. stainless steel, Titanium and Titanium alloys) are much stiffer than spongy cancellous and even stiffer than cortical bone. When bone and implant are loaded this stiffness mismatch results in stress shielding and as a consequence, degradation of surrounding bony structure can lead to disassociation of the implant. Due to its lower stiffness and high reversible deformability, which is associated with the superelastic behavior, NiTi is an attractive biomaterial for load bearing implants. However, the stiffness of austenitic Nitinol is closer to that of bone but still too high. Additive manufacturing provides, in addition to the fabrication of patient specific implants, the ability to solve the stiffness mismatch by adding engineered porosity to the implant. This in turn allows for the design of different stiffness profiles in one implant tailored to the physiological load conditions. This work covers a fundamental approach to bring this vision to reality. At first modeling of the mechanical behavior of different scaffold designs are presented as a proof of concept of stiffness tailoring. Based on these results different Nitinol scaffolds can be produced by additive manufacturing.

  12. Parameters and pitfalls to consider in the conduct of food additive research, Carrageenan as a case study.

    PubMed

    Weiner, Myra L

    2016-01-01

    This paper provides guidance on the conduct of new in vivo and in vitro studies on high molecular weight food additives, with carrageenan, the widely used food additive, as a case study. It is important to understand the physical/chemical properties and to verify the identity/purity, molecular weight and homogeneity/stability of the additive in the vehicle for oral delivery. The strong binding of CGN to protein in rodent chow or infant formula results in no gastrointestinal tract exposure to free CGN. It is recommended that doses of high Mw non-caloric, non-nutritive additives not exceed 5% by weight of total solid diet to avoid potential nutritional effects. Addition of some high Mw additives at high concentrations to liquid nutritional supplements increases viscosity and may affect palatability, caloric intake and body weight gain. In in vitro studies, the use of well-characterized, relevant cell types and the appropriate composition of the culture media are necessary for proper conduct and interpretation. CGN is bound to media protein and not freely accessible to cells in vitro. Interpretation of new studies on food additives should consider the interaction of food additives with the vehicle components and the appropriateness of the animal or cell model and dose-response. PMID:26615870

  13. Local Studies Collections Online: An Investigation in Irish Public Libraries

    ERIC Educational Resources Information Center

    Barry, Lara; Tedd, Lucy A.

    2008-01-01

    Purpose: This paper aims to investigate how public libraries in Ireland are using their websites to present local studies collections online. Design/methodology/approach: All the websites of public libraries in Ireland were evaluated against a checklist of 50 criteria by one of the authors. An analytic description was provided of the four…

  14. A Reporting and Study Format for University Student Retention Investigations.

    ERIC Educational Resources Information Center

    Hopp, David I.

    A reporting and study format for the investigation of university student retention is presented. Student progression and loss is shown graphically and in tabular form to enable ready comprehension and encourage data exploration. Data obtained at Virginia Commonwealth University for 1977-80 are used as illustration. Two ways of viewing student…

  15. Highway Traffic Accident Investigation and Reporting: Student Study Guide.

    ERIC Educational Resources Information Center

    Daugherty, Ronald D.; And Others

    This study guide for students in a basic training program for accident investigation is intended for use with lesson plans for the instructor and a manual for administrators and planners, available as VT 019 457 and VT 019 455, respectively. As part of a curriculum package developed by the Center for Vocational and Technical Education after a…

  16. Alignments, additivity, and signature inversion in odd-odd {sup 170}Ta : a comprehensive high-spin study.

    SciTech Connect

    Aguilar, A.; Hartley, D. J.; Riley, M. A.; Teal, C.; Carpenter, M. P.; Chowdhury, P.; Danchev, M.; Djongolov, M. K.; Hagemann, G. B.; Hecht, A. A.; Janssens, R. V. F.; Kondev, F. G.; Lauritsen, T.; Ma, W. C.; Mohr, W. H.; Moore, E. F.; Odegard, S. W.; Riedinger, L. L.; Sletten, G.; Tandel, S. K.; Vanhoy, J. R.; Wang, X.; Zhu, S.; Florida State Univ.; U.S. Naval Academy; Univ. of Massachusetts; Univ. of Tennessee; Niels Bohr Inst.; Mississippi State Univ.; Univ. of Oslo

    2010-01-01

    High-spin states (I?50?) of the odd-odd nucleus 170Ta have been investigated with the 124Sn(51V,5n) reaction. The resolving power of Gammasphere has allowed for the observation of eleven rotational bands (eight of which are new) and over 430 transitions ( 350 of which are new) in this nucleus. Many interband transitions have been observed such that the relative spins and excitation energies of the 11 bands have been established. This is an unusual circumstance in an odd-odd study. Configurations have been assigned to most of these bands based upon features such as alignment properties, band crossings, B(M1)/B(E2) ratios, and the additivity of Routhians. A systematic study of the frequency at which normal signature ordering occurs in the ?h9/2?i13/2 band has been performed and it is found that its trend is opposite to that observed in the ?h11/2?i13/2 bands. A possible interpretation of these trends is discussed based on a proton-neutron interaction.

  17. Numerical investigation of the mechanical properties of the additive manufactured bone scaffolds fabricated by FDM: The effect of layer penetration and post-heating.

    PubMed

    Naghieh, S; Karamooz Ravari, M R; Badrossamay, M; Foroozmehr, E; Kadkhodaei, M

    2016-06-01

    In recent years, thanks to additive manufacturing technology, researchers have gone towards the optimization of bone scaffolds for the bone reconstruction. Bone scaffolds should have appropriate biological as well as mechanical properties in order to play a decisive role in bone healing. Since the fabrication of scaffolds is time consuming and expensive, numerical methods are often utilized to simulate their mechanical properties in order to find a nearly optimum one. Finite element analysis is one of the most common numerical methods that is used in this regard. In this paper, a parametric finite element model is developed to assess the effects of layers penetration׳s effect on inter-layer adhesion, which is reflected on the mechanical properties of bone scaffolds. To be able to validate this model, some compression test specimens as well as bone scaffolds are fabricated with biocompatible and biodegradable poly lactic acid using fused deposition modeling. All these specimens are tested in compression and their elastic modulus is obtained. Using the material parameters of the compression test specimens, the finite element analysis of the bone scaffold is performed. The obtained elastic modulus is compared with experiment indicating a good agreement. Accordingly, the proposed finite element model is able to predict the mechanical behavior of fabricated bone scaffolds accurately. In addition, the effect of post-heating of bone scaffolds on their elastic modulus is investigated. The results demonstrate that the numerically predicted elastic modulus of scaffold is closer to experimental outcomes in comparison with as-built samples. PMID:26874065

  18. Reference Alloy Waste Form Fabrication and Initiation of Reducing Atmosphere and Reductive Additives Study on Alloy Waste Form Fabrication

    SciTech Connect

    S.M. Frank; T.P. O'Holleran; P.A. Hahn

    2011-09-01

    This report describes the fabrication of two reference alloy waste forms, RAW-1(Re) and RAW-(Tc) using an optimized loading and heating method. The composition of the alloy materials was based on a generalized formulation to process various proposed feed streams resulting from the processing of used fuel. Waste elements are introduced into molten steel during alloy fabrication and, upon solidification, become incorporated into durable iron-based intermetallic phases of the alloy waste form. The first alloy ingot contained surrogate (non-radioactive), transition-metal fission products with rhenium acting as a surrogate for technetium. The second alloy ingot contained the same components as the first ingot, but included radioactive Tc-99 instead of rhenium. Understanding technetium behavior in the waste form is of particular importance due the longevity of Tc-99 and its mobility in the biosphere in the oxide form. RAW-1(Re) and RAW-1(Tc) are currently being used as test specimens in the comprehensive testing program investigating the corrosion and radionuclide release mechanisms of the representative alloy waste form. Also described in this report is the experimental plan to study the effects of reducing atmospheres and reducing additives to the alloy material during fabrication in an attempt to maximize the oxide content of waste streams that can be accommodated in the alloy waste form. Activities described in the experimental plan will be performed in FY12. The first aspect of the experimental plan is to study oxide formation on the alloy by introducing O2 impurities in the melt cover gas or from added oxide impurities in the feed materials. Reducing atmospheres will then be introduced to the melt cover gas in an attempt to minimize oxide formation during alloy fabrication. The second phase of the experimental plan is to investigate melting parameters associated with alloy fabrication to allow the separation of slag and alloy components of the melt.

  19. Early Additional Immune-Modulators for Mycoplasma pneumoniae Pneumonia in Children: An Observation Study

    PubMed Central

    Lee, Sung-Churl; Rhim, Jung-Woo; Shin, Myung-Seok; Kang, Jin-Han

    2014-01-01

    Background Mycoplasma pneumoniae (MP) pneumonia is a self-limiting disease, but some patients complain of progressive pneumonia, despite of appropriate antibiotic treatment. We aimed to introduce the role of immune-modulators (corticosteroid and/or intravenous immunoglobulin, IVIG) treatment for childhood MP pneumonia based on previous our experiences. Materials and Methods A retrospective case series analysis for 183 children with MP pneumonia was performed. MP pneumonia patients were diagnosed by two Immunoglobulin M (IgM) tests: the micro-particle agglutination method (≥1:40) and the cold agglutination test (≥1:4), and were examined twice at the initial admission and at discharge. Among 183 MP pneumonia patients, 90 patients with persistent fever for over 48 hours after admission or those with severe respiratory symptoms and signs received additional prednisolone (82 patients, 1 mg/kg/day) or intravenous methylprednisolone (8 patients, 5-10 mg/kg/day) with antibiotics. Four patients with aggravated clinical symptoms and chest radiographic findings after corticosteroid treatment received IVIG (1 g/kg/day, 1-2 doses). Results Mean age of 183 patients was 5.5 ± 3.2 years (6 months-15 years), and the male: female ratio was 1.1:1 (96:87). Fifty-seven patients (31%) were seroconverters and 126 seropositive patients showed increased diagnostic IgM antibody titres during admission (over 4 folds). The majority of the patients who received corticosteroids (86/90 cases) showed rapid defervescence within 48 hours with improved clinical symptoms, regardless of the used antibiotics. Also, 4 patients who received additional IVIG improved both clinically and radiographically within 2 days without adverse reaction. Conclusions In the era of macrolide-resistant MP strains, early additional immune-modulator therapy with antibiotics might prevent from the disease progression and reduce the disease morbidity without adverse reaction. PMID:25566403

  20. Strategic Petroleum Reserve (SPR) additional geologic site characterization studies, Bryan Mound Salt Dome, Texas

    SciTech Connect

    Neal, J.T.; Magorian, T.R.; Ahmad, S.

    1994-11-01

    This report revises the original report that was published in 1980. Some of the topics covered in the earlier report were provisional and it is now practicable to reexamine them using new or revised geotechnical data and that obtained from SPR cavern operations, which involves 16 new caverns. Revised structure maps and sections show interpretative differences as compared with the 1980 report and more definition in the dome shape and caprock structural contours, especially a major southeast-northwest trending anomalous zone. The original interpretation was of westward tilt of the dome, this revision shows a tilt to the southeast, consistent with other gravity and seismic data. This interpretation refines the evaluation of additional cavern space, by adding more salt buffer and allowing several more caverns. Additional storage space is constrained on this nearly full dome because of low-lying peripheral wetlands, but 60 MMBBL or more of additional volume could be gained in six or more new caverns. Subsidence values at Bryan Mound are among the lowest in the SPR system, averaging about 11 mm/yr (0.4 in/yr), but measurement and interpretation issues persist, as observed values are about the same as survey measurement accuracy. Periodic flooding is a continuing threat because of the coastal proximity and because peripheral portions of the site are at elevations less than 15 ft. This threat may increase slightly as future subsidence lowers the surface, but the amount is apt to be small. Caprock integrity may be affected by structural features, especially the faulting associated with anomalous zones. Injection wells have not been used extensively at Bryan Mound, but could be a practicable solution to future brine disposal needs. Environmental issues center on the areas of low elevation that are below 15 feet above mean sea level: the coastal proximity and lowland environment combined with the potential for flooding create conditions that require continuing surveillance.

  1. Investigation of Poultry Waste for Anaerobic Digestion: A Case Study

    NASA Astrophysics Data System (ADS)

    Salam, Christopher R.

    Anaerobic Digestion (AD) is a biological conversion technology which is being used to produce bioenergy all over the world. This energy is created from biological feedstocks, and can often use waste products from various food and agricultural processors. Biogas from AD can be used as a fuel for heating or for co-generation of electricity and heat and is a renewable substitute to using fossil fuels. Nutrient recycling and waste reduction are additional benefits, creating a final product that can be used as a fertilizer in addition to energy benefits. This project was conducted to investigate the viability of three turkey production wastes as AD feedstock: two turkey litters and a material separated from the turkey processing wastewater using dissolved air flotation (DAF) process. The DAF waste contained greases, oils and other non-commodity portions of the turkey. Using a variety of different process methods, types of bacteria, loading rates and food-to-microorganism ratios, optimal loading rates for the digestion of these three materials were obtained. In addition, the co-digestion of these materials revealed additional energy benefits. In this study, batch digestion tests were carried out to treat these three feedstocks, using mesophilic and thermophilic bacteria, using loading rates of 3 and 6 gVS/L They were tested separately and also as a mixture for co-digestion. The batch reactor used in this study had total and working volumes of 1130 mL and 500 mL, respectively. The initial organic loading was set to be 3 gVS/L, and the food to microorganism ratio was either 0.6 or 1.0 for different treatments based on the characteristics of each material. Only thermophilic (50 +/- 2ºC) temperatures were tested for the litter and DAF wastes in continuous digestion, but mesophilic and thermophilic batch digestion experiments were conducted. The optimum digestion time for all experiments was 14 days. The biogas yields of top litter, mixed litter, and DAF waste under

  2. A near-infrared spectroscopic study of young field ultracool dwarfs: additional analysis

    NASA Astrophysics Data System (ADS)

    Allers, K. N.; Liu, M. C.

    We present additional analysis of the classification system presented in \\citet{allers13}. We refer the reader to \\citet{allers13} for a detailed discussion of our near-IR spectral type and gravity classification system. Here, we address questions and comments from participants of the Brown Dwarfs Come of Age meeting. In particular, we examine the effects of binarity and metallicity on our classification system. We also present our classification of Pleiades brown dwarfs using published spectra. Lastly, we determine SpTs and calculate gravity-sensitive indices for the BT-Settl atmospheric models and compare them to observations.

  3. The influence of bioaugmentation and biosurfactant addition on bioremediation efficiency of diesel-oil contaminated soil: feasibility during field studies.

    PubMed

    Szulc, Alicja; Ambrożewicz, Damian; Sydow, Mateusz; Ławniczak, Łukasz; Piotrowska-Cyplik, Agnieszka; Marecik, Roman; Chrzanowski, Łukasz

    2014-01-01

    The study focused on assessing the influence of bioaugmentation and addition of rhamnolipids on diesel oil biodegradation efficiency during field studies. Initial laboratory studies (measurement of emitted CO2 and dehydrogenase activity) were carried out in order to select the consortium for bioaugmentation as well as to evaluate the most appropriate concentration of rhamnolipids. The selected consortium consisted of following bacterial taxa: Aeromonas hydrophila, Alcaligenes xylosoxidans, Gordonia sp., Pseudomonas fluorescens, Pseudomonas putida, Rhodococcus equi, Stenotrophomonas maltophilia, Xanthomonas sp. It was established that the application of rhamnolipids at 150 mg/kg of soil was most appropriate in terms of dehydrogenase activity. Based on the obtained results, four treatment methods were designed and tested during 365 days of field studies: I) natural attenuation; II) addition of rhamnolipids; III) bioaugmentation; IV) bioaugmentation and addition of rhamnolipids. It was observed that bioaugmentation contributed to the highest diesel oil biodegradation efficiency, whereas the addition of rhamnolipids did not notably influence the treatment process. PMID:24291585

  4. Studying the issues in the additive manufacturing of dental implants by Electron Beam MeltingRTM (EBM)

    NASA Astrophysics Data System (ADS)

    Jamshidinia, Mahdi

    The ability of additive manufacturing (AM) processes to produce complex geometries is resulting in their rapid acceptance by a number of industries. This unique capability could be used for the optimization of the design of functional components that could find an application in different industries such as aerospace, automotive, energy, medical, and implants. However, there are still some challenges confronting this technology such as surface finish, residual stress, dimensional tolerance, processing speed, and anisotropy in microstructure and mechanical properties. Any of the mentioned issues could be influenced by the thermal history of a 3D printed component during the layer-by-layer manufacturing. Therefore, an understanding of the thermal cycling during the AM process is essential. In recent years, significant advances have been achieved in the design, manufacturing, and materials used for dental implants. However, there are still some differences between the natural tooth and a dental implant that might decrease patient satisfaction. One of the differences between the natural tooth and a dental implant is in its modulus of elasticity, which could result in an issue known as bone atrophy. The second important difference between a dental implant and a natural tooth is the fact that a natural tooth is surrounded by a periodontal ligament that allows the tooth to move in three directions. However, the periodontal ligament is destroyed during the extraction of a natural tooth. In the absence of the periodontal ligament, the biting force is directly transferred to the jawbone, resulting in discomfort for the patient. Also, the implant cannot be incorporated with the surrounding natural tooth and form a bridge. In this study, the application of a lattice structure for the manufacturing of a biocompatible dental implant is investigated. Three different lattice structures with different unit cell sizes were experimentally and numerically analyzed. The mechanical

  5. Professional Competence Development of the Social Work Specialists in the Period of Study in the System of Additional Education

    ERIC Educational Resources Information Center

    Davletkaliev, Denis Kuanyshevich; Zueva, Natalia Konstantinovna; Lebedeva, Natalya Vasilevna; Mkrtumova, Irina Vladimirovna; Timofeeva, Olga

    2015-01-01

    The goal of this work is the study of psychological-pedagogical approaches to the understanding of the idea of professional competence of social work specialists as well as the role of study in the system of additional educations in professional-personal development of the listeners. In the process of study of this problem we define main…

  6. Preliminary study of neutron absorption by concrete with boron carbide addition

    SciTech Connect

    Abdullah, Yusof Yusof, Mohd Reusmaazran; Zali, Nurazila Mat; Ahmad, Megat Harun Al Rashid Megat; Yazid, Hafizal; Ariffin, Fatin Nabilah Tajul; Ahmad, Sahrim; Hamid, Roszilah; Mohamed, Abdul Aziz

    2014-02-12

    Concrete has become a conventional material in construction of nuclear reactor due to its properties like safety and low cost. Boron carbide was added as additives in the concrete construction as it has a good neutron absorption property. The sample preparation for concrete was produced with different weight percent of boron carbide powder content. The neutron absorption rate of these samples was determined by using a fast neutron source of Americium-241/Be (Am-Be 241) and detection with a portable backscattering neutron detector. Concrete with 20 wt % of boron carbide shows the lowest count of neutron transmitted and this indicates the most neutrons have been absorbed by the concrete. Higher boron carbide content may affect the concrete strength and other properties.

  7. A study of the effects of an additional sound source on RASS performance

    SciTech Connect

    Coulter, R.L.

    1998-12-31

    The Southern Great Plains (SGP) Cloud and Radiation Testbed (CART) site of the Atmospheric Radiation Measurements (ARM) Program continuously operates a nine panel 915 MHz wind profiler with Radio Acoustic Sounding System (RASS), measuring wind profiles for 50 minutes and virtual temperature profiles for the remaining 10 minutes during each hour. It is well recognized that one of the principal limits on RASS performance is high horizontal wind speed that moves the acoustic wave front sufficiently to prevent the microwave energy produced by the radar and scattered from the acoustic wave from being reflected back t the radar antenna. With this limitation in mind, the ARM program purchased an additional, portable acoustic source that could be mounted on a small trailer and placed in strategic locations to enhance the RASS performance (when it was not being used for spare parts). A test of the resulting improvement in RASS performance was performed during the period 1995--1997.

  8. Additive Manufacturing of a Microbial Fuel Cell—A detailed study

    PubMed Central

    Calignano, Flaviana; Tommasi, Tonia; Manfredi, Diego; Chiolerio, Alessandro

    2015-01-01

    In contemporary society we observe an everlasting permeation of electron devices, smartphones, portable computing tools. The tiniest living organisms on Earth could become the key to address this challenge: energy generation by bacterial processes from renewable stocks/waste through devices such as microbial fuel cells (MFCs). However, the application of this solution was limited by a moderately low efficiency. We explored the limits, if any, of additive manufacturing (AM) technology to fabricate a fully AM-based powering device, exploiting low density, open porosities able to host the microbes, systems easy to fuel continuously and to run safely. We obtained an optimal energy recovery close to 3 kWh m−3 per day that can power sensors and low-power appliances, allowing data processing and transmission from remote/harsh environments. PMID:26611142

  9. THERMODYNAMIC STUDY OF THE NICKEL ADDITION IN ZINC HOT-DIP GALVANIZING BATHS

    SciTech Connect

    Pistofidis, N.; Vourlias, G.

    2010-01-21

    A usual practice during zinc hot-dip galvanizing is the addition of nickel in the liquid zinc which is used to inhibit the Sandelin effect. Its action is due to the fact that the zeta(zeta) phase of the Fe-Zn system is replaced by the TAU(tau) phase of the Fe-Zn-Ni system. In the present work an attempt is made to explain the formation of the TAU phase with thermodynamics. For this reason the Gibbs free energy changes for TAU and zeta phases were calculated. The excess free energy for the system was calculated with the Redlich-Kister polyonyme. From this calculation it was deduced that the Gibbs energy change for the tau phase is negative. As a result its formation is spontaneous.

  10. Preliminary study of neutron absorption by concrete with boron carbide addition

    NASA Astrophysics Data System (ADS)

    Abdullah, Yusof; Ariffin, Fatin Nabilah Tajul; Hamid, Roszilah; Yusof, Mohd Reusmaazran; Zali, Nurazila Mat; Ahmad, Megat Harun Al Rashid Megat; Yazid, Hafizal; Ahmad, Sahrim; Mohamed, Abdul Aziz

    2014-02-01

    Concrete has become a conventional material in construction of nuclear reactor due to its properties like safety and low cost. Boron carbide was added as additives in the concrete construction as it has a good neutron absorption property. The sample preparation for concrete was produced with different weight percent of boron carbide powder content. The neutron absorption rate of these samples was determined by using a fast neutron source of Americium-241/Be (Am-Be 241) and detection with a portable backscattering neutron detector. Concrete with 20 wt % of boron carbide shows the lowest count of neutron transmitted and this indicates the most neutrons have been absorbed by the concrete. Higher boron carbide content may affect the concrete strength and other properties.

  11. Sulphur diffusion in β-NiAl and effect of Pt additive: an ab initio study

    NASA Astrophysics Data System (ADS)

    Chen, Kuiying

    2016-02-01

    Diffusivities of detrimental impurity sulfur (S) in stoichiometric and Pt doped β-NiAl were evaluated using density functional theory calculations. The apparent activation energy and the pre-exponential factor of diffusivity via the next nearest neighbour (NNN) and interstitial jumps were evaluated to identify possible preferred diffusion mechanism(s). By calculating the electron localization function (ELF), the bonding characteristics of S with its surrounding atoms were assessed for the diffusion process. By comparison with the experimental results, the S diffusion through the NNN vacancy-mediated mechanism is found to be favoured. Addition of Pt in β-NiAl was found to significantly reduce the S diffusivity, and an associated electronic effect was explored. The elucidation of the above mechanisms may shed light on the development of new Pt-modified doped β-NiAl bond coats that can extend the life of oxidation resistant and thermal barrier coatings.

  12. Additive Manufacturing of a Microbial Fuel Cell--A detailed study.

    PubMed

    Calignano, Flaviana; Tommasi, Tonia; Manfredi, Diego; Chiolerio, Alessandro

    2015-01-01

    In contemporary society we observe an everlasting permeation of electron devices, smartphones, portable computing tools. The tiniest living organisms on Earth could become the key to address this challenge: energy generation by bacterial processes from renewable stocks/waste through devices such as microbial fuel cells (MFCs). However, the application of this solution was limited by a moderately low efficiency. We explored the limits, if any, of additive manufacturing (AM) technology to fabricate a fully AM-based powering device, exploiting low density, open porosities able to host the microbes, systems easy to fuel continuously and to run safely. We obtained an optimal energy recovery close to 3 kWh m(-3) per day that can power sensors and low-power appliances, allowing data processing and transmission from remote/harsh environments. PMID:26611142

  13. Additive Manufacturing of a Microbial Fuel Cell—A detailed study

    NASA Astrophysics Data System (ADS)

    Calignano, Flaviana; Tommasi, Tonia; Manfredi, Diego; Chiolerio, Alessandro

    2015-11-01

    In contemporary society we observe an everlasting permeation of electron devices, smartphones, portable computing tools. The tiniest living organisms on Earth could become the key to address this challenge: energy generation by bacterial processes from renewable stocks/waste through devices such as microbial fuel cells (MFCs). However, the application of this solution was limited by a moderately low efficiency. We explored the limits, if any, of additive manufacturing (AM) technology to fabricate a fully AM-based powering device, exploiting low density, open porosities able to host the microbes, systems easy to fuel continuously and to run safely. We obtained an optimal energy recovery close to 3 kWh m-3 per day that can power sensors and low-power appliances, allowing data processing and transmission from remote/harsh environments.

  14. Seniors Falls Investigative Methodology (SFIM): a systems approach to the study of falls in seniors.

    PubMed

    Zecevic, Aleksandra A; Salmoni, Alan W; Lewko, John H; Vandervoort, Anthony A

    2007-01-01

    An in-depth understanding of human factors and human error is lacking in current research on seniors' falls. Additional knowledge is needed to understand why seniors are falling. The purpose of this article is to describe the adapting of the Integrated Safety Investigation Methodology (ISIM) (used for investigating transportation and industrial accidents) to studying seniors' falls. An adapted version-the Seniors Falls Investigative Methodology (SFIM)-uses a systems approach to take an investigation beyond the immediate cause of an incident and reveal unsafe acts and deeply imbedded unsafe conditions that contribute to adverse outcomes. An example case study is used to describe six phases of the investigative process in detail. The SFIM has the potential to identify safety deficiencies; utilize existing knowledge about falls; establish a standardized reporting system; shift focus from the faller to the system; and guide targeted prevention. PMID:18238732

  15. Sensitization to Food Additives in Patients with Allergy: A Study Based on Skin Test and Open Oral Challenge.

    PubMed

    Moghtaderi, Mozhgan; Hejrati, Zinatosadat; Dehghani, Zahra; Dehghani, Faranak; Kolahi, Niloofar

    2016-06-01

    There has been a great increase in the consumption of various food additives in recent years. The purpose of this study was to identify the incidence of sensitization to food additives by using skin prick test in patients with allergy and to determine the concordance rate between positive skin tests and oral challenge in hypersensitivity to additives. This cross-sectional study included 125 (female 71, male 54) patients aged 2-76 years with allergy and 100 healthy individuals. Skin tests were performed in both patient and control groups with 25 fresh food additives. Among patients with allergy, 22.4% showed positive skin test at least to one of the applied materials. Skin test was negative to all tested food additives in control group. Oral food challenge was done in 28 patients with positive skin test, in whom 9 patients showed reaction to culprit (Concordance rate=32.1%). The present study suggested that about one-third of allergic patients with positive reaction to food additives showed positive oral challenge; it may be considered the potential utility of skin test to identify the role of food additives in patients with allergy. PMID:27424134

  16. Theoretical study of the OH addition to the endocyclic and exocyclic double bonds of the d-limonene

    NASA Astrophysics Data System (ADS)

    Ramírez-Ramírez, Víctor M.; Nebot-Gil, Ignacio

    2005-06-01

    The initial step of the d-limonene + OH gas-phase reaction mechanism was investigated by means of ab initio calculations. We have considered eight different possibilities for the OH addition, corresponding to the two C-C double bonds, the two C atoms of each double bond, and the syn or anti orientation, with respect to the isopropenyl group (endocyclic attack) or the ring cycle (exocyclic attack). Activation energies calculated at the QCISD(T)/6-31G(d)//UMP2/6-31G(d) level, show that there are preferred orientations for the OH addition under atmospheric conditions of temperature and pressure.

  17. Characterization and comparative study of coal combustion residues from a primary and additional flue gas secondary desulfurization process

    SciTech Connect

    Gomes, S.; Francois, M.; Evrard, O.; Pellissier, C.

    1998-11-01

    An extensive characterization and comparative study was done on two flue gas desulfurization (FGD) residues derived from the same coal. LR residues (originated from Loire/Rhone in the south of Lyon, France) are obtained after a primary desulfurization process (SO{sub 2} is trapped by reaction with CaO at a temperature of about 1100 C), and LM residues (originating from La Maxe, near Metz in the east of France) are obtained after an additional secondary desulfurization process (SO{sub 2} is removed further by reaction with Ca(OH){sub 2} at a temperature of about 120 C). Various and complementary investigation methods were used to determine their chemical, physical, and mineralogical properties: x-ray fluorescence and diffraction, scanning electron microscopy, differential scanning calorimetry, thermogravimetry analysis, granulometric distribution, pycnometric density, BET specific surface area and pH, conductivity measurements, and chemical analysis of their insoluble fraction. The FGD residues contain basically two main components: a silico-aluminous fly ash part and calcic FGD phases. In the LR residues the two components can be considered as independent, whereas they are linked in the LM residues because chemical reactions have occurred, leading to the formation of silico-calcic gel CSH, hydrated aluminate AFm, and AFt phases.

  18. Additive technology of soluble mold tooling for embedded devices in composite structures: A study on manufactured tolerances

    NASA Astrophysics Data System (ADS)

    Roy, Madhuparna

    Composite textiles have found widespread use and advantages in various industries and applications. The constant demand for high quality products and services requires companies to minimize their manufacturing costs, and delivery time in order to compete in general and niche marketplaces. Advanced manufacturing methods aim to provide economical methods of mold production. Creation of molding and tooling options for advanced composites encompasses a large portion of the fabrication time, making it a costly process and restraining factor. This research discusses a preliminary investigation into the use of soluble polymer compounds and additive manufacturing to fabricate soluble molds. These molds suffer from dimensional errors due to several factors, which have also been characterized. The basic soluble mold of a composite is 3D printed to meet the desired dimensions and geometry of holistic structures or spliced components. The time taken to dissolve the mold depends on the rate of agitation of the solvent. This process is steered towards enabling the implantation of optoelectronic devices within the composite to provide sensing capability for structural health monitoring. The shape deviation of the 3D printed mold is also studied and compared to its original dimensions to optimize the dimensional quality to produce dimensionally accurate parts. Mechanical tests were performed on compact tension (CT) resin samples prepared from these 3D printed molds and revealed crack propagation towards an embedded intact optical fiber.

  19. Small angle neutron scattering study of sodium dodecyl sulfate micellar growth driven by addition of a hydrotropic salt.

    PubMed

    Hassan, P A; Fritz, Gerhard; Kaler, Eric W

    2003-01-01

    The structures of aggregates formed in aqueous solutions of an anionic surfactant, sodium dodecyl sulfate (SDS), with the addition of a cationic hydrotropic salt, p-toluidine hydrochloride (PTHC), have been investigated by small angle neutron scattering (SANS). The SANS spectra exhibit a pronounced peak at low salt concentration, indicating the presence of repulsive intermicellar interactions. Model-independent real space information about the structure is obtained from a generalized indirect Fourier transformation (GIFT) technique in combination with a suitable model for the interparticle structure factor. The interparticle interaction is captured using the rescaled mean spherical approximation (RMSA) closure relation and a Yukawa form of the interaction potential. Further quantification of the geometrical parameters of the micelles was achieved by a complete fit of the SANS data using a prolate ellipsoidal form factor and the RMSA structure factor. The present study shows that PTHC induces a decrease in the fractional charge of the micelles due to adsorption at the micellar surface and consequent growth of the SDS micelles from nearly globular to rodlike as the concentration of PTHC increases. PMID:16256467

  20. Shock-implanted noble gases. II - Additional experimental studies and recognition in naturally shocked terrestrial materials

    NASA Astrophysics Data System (ADS)

    Bogard, D.; Horz, F.; Johnson, P.

    1989-06-01

    The process by which ambient gases can be implanted into silicates by shocks was investigated by analyzing the noble-gas content of several experimentally and naturally shocked silicate samples. The retentivity of shock-implanted gas during stepwise heating in the laboratory was defined in terms of two parameters, namely, the activation energy for diffusion and the extraction temperature at which 50 percent of the gas is released, both of which correlate with the shock pressure. The experiments indicate that, with increasing shock pressure, gas implantation occurs through an increasing production of microcracks/defects in the silicate lattice. The degree of annealing of these defects control the degree of diffusive loss of implanted gas.

  1. Te Rita Papesch: Case Study of an Exemplary Learner of Maori as an Additional Language

    ERIC Educational Resources Information Center

    Ratima, Matiu Tai; Papesch, Te Rita

    2014-01-01

    This paper presents a case study of the life experiences of one exemplar adult second language Maori learner--Te Rita Papesch. Te Rita was one of 17 participants who were interviewed as a part of the first author's PhD study which sought to answer the question: what factors lead to the development of proficiency in te reo Maori amongst adult…

  2. Study of NiO cathode modified by ZnO additive for MCFC

    NASA Astrophysics Data System (ADS)

    Huang, Bo; Li, Fei; Yu, Qing-chun; Chen, Gang; Zhao, Bin-yuan; Hu, Ke-ao

    The preparation and subsequent oxidation of nickel cathodes modified by impregnation with zinc oxide (ZnO) were evaluated by surface and bulk analysis. The electrochemical behaviors of ZnO impregnated NiO cathodes was also evaluated in a molten 62 mol% Li 2CO 3 + 38 mol% K 2CO 3 eutectic at 650 °C by electrochemical impedance spectroscopy (EIS) as a function of ZnO content and immersion time. The ZnO impregnated nickel cathodes showed the similar porosity, pore size distribution and morphology to the reference nickel cathode. The stability tests of ZnO impregnated NiO cathodes showed that the ZnO additive could dramatically reduce the solubility of NiO in a eutectic carbonate mixture under the standard cathode gas condition. The impedance spectra for cathode materials show important variations during the 100 h of immersion. The incorporation of lithium in its structure and the low dissolution of nickel oxide and zinc oxide are responsible of these changes. After that, the structure reaches a stable state. The cathode material having 2 mol% of ZnO showed a very low dissolution and a good catalytic efficiency close to the NiO value. We thought that 2 mol% ZnO/NiO materials would be able to adapt as alternative cathode materials for MCFCs.

  3. Generalized linear and generalized additive models in studies of species distributions: Setting the scene

    USGS Publications Warehouse

    Guisan, A.; Edwards, T.C., Jr.; Hastie, T.

    2002-01-01

    An important statistical development of the last 30 years has been the advance in regression analysis provided by generalized linear models (GLMs) and generalized additive models (GAMs). Here we introduce a series of papers prepared within the framework of an international workshop entitled: Advances in GLMs/GAMs modeling: from species distribution to environmental management, held in Riederalp, Switzerland, 6-11 August 2001. We first discuss some general uses of statistical models in ecology, as well as provide a short review of several key examples of the use of GLMs and GAMs in ecological modeling efforts. We next present an overview of GLMs and GAMs, and discuss some of their related statistics used for predictor selection, model diagnostics, and evaluation. Included is a discussion of several new approaches applicable to GLMs and GAMs, such as ridge regression, an alternative to stepwise selection of predictors, and methods for the identification of interactions by a combined use of regression trees and several other approaches. We close with an overview of the papers and how we feel they advance our understanding of their application to ecological modeling. ?? 2002 Elsevier Science B.V. All rights reserved.

  4. Numerical study of the effect of water addition on gas explosion.

    PubMed

    Liang, Yuntao; Zeng, Wen

    2010-02-15

    Through amending the SENKIN code of CHEMKIN III chemical kinetics package, a computational model of gas explosion in a constant volume bomb was built, and the detailed reaction mechanism (GRI-Mech 3.0) was adopted. The mole fraction profiles of reactants, some selected free radicals and catastrophic gases in the process of gas explosion were analyzed by this model. Furthermore, through the sensitivity analysis of the reaction mechanism of gas explosion, the dominant reactions that affect gas explosion and the formation of catastrophic gases were found out. At the same time, the inhibition mechanisms of water on gas explosion and the formation of catastrophic gases were analyzed. The results show that the induced explosion time is prolonged, and the mole fractions of reactant species such as CH(4), O(2) and catastrophic gases such as CO, CO(2) and NO are decreased as water is added to the mixed gas. With the water fraction in the mixed gas increasing, the sensitivities of the dominant reactions contributing to CH(4), CO(2) are decreased and the sensitivity coefficients of CH(4), CO and NO mole fractions are also decreased. The inhibition of gas explosion with water addition can be ascribed to the significant decrease of H, O and OH in the process of gas explosion due to the water presence. PMID:19811873

  5. Exploratory studies of extended storage of apheresis platelets in a platelet additive solution (PAS).

    PubMed

    Slichter, Sherrill J; Corson, Jill; Jones, Mary Kay; Christoffel, Todd; Pellham, Esther; Bailey, S Lawrence; Bolgiano, Doug

    2014-01-01

    To evaluate the poststorage viability of apheresis platelets stored for up to 18 days in 80% platelet additive solution (PAS)/20% plasma, 117 healthy subjects donated platelets using the Haemonetics MCS+, COBE Spectra (Spectra), or Trima Accel (Trima) systems. Control platelets from the same subjects were compared with their stored test PAS platelets by radiolabeling their stored and control platelets with either (51)chromium or (111)indium. Trima platelets met Food and Drug Administration poststorage platelet viability criteria for only 7 days vs almost 13 days for Haemonetics platelets; ie, platelet recoveries after these storage times averaged 44 ± 3% vs 49 ± 3% and survivals were 5.4 ± 0.3 vs 4.6 ± 0.3 days, respectively. The differences in storage duration are likely related to both the collection system and the storage bag. The Spectra and Trima platelets were hyperconcentrated during collection, and PAS was added, whereas the Haemonetics platelets were elutriated with PAS, which may have resulted in less collection injury. When Spectra and Trima platelets were stored in Haemonetics' bags, poststorage viability was significantly improved. Platelet viability is better maintained in vitro than in vivo, allowing substantial increases in platelet storage times. However, implementation will require resolution of potential bacterial overgrowth during storage. PMID:24258816

  6. Study of investigation-derived waste management options. Master's thesis

    SciTech Connect

    Mountain, B.C.

    1993-09-01

    USAF is dedicated to the clean up of past releases of hazardous substances at its bases under the Installation Restoration Program (IRP) . Clean up decisions are based upon data produced from investigations. Large amounts of waste may be derived from investigations. Investigation-derived waste (IDW), especially that with a hazardous component, may pose significant health protection and regulatory compliance problems if neglected. This study identifies the status and the need for improvement of IDW management to avoid those problems. Information on the background of IDW management was collected through a review of environmental laws, waste management regulations, and existing guidance. Practical IDW management information was gleaned from conversations with iRP managers at twelve USAF bases around the country. This study revealed that IDW management needs improvement. All bases acknowledged IDW concerns and have adopted various methods to deal with them. However, current methods appear to rely more upon expediency rather than permanence. This study showed that critical protection and compliance issues are being overlooked. Development of specific IDW management guidance may better assure that critical issues are addressed. Waste minimization, Waste management, Environmental management, Nonhazardous wastes, Hazardous material, Solid wastes.

  7. How knowledgeable are investigators studying therapies of traditional medicines?

    PubMed Central

    Narahari, Saravu R.; Aggithaya, Madhur G.; Thamban, Chendalam; Muralidharan, Kunnathody; Kanjarpane, Aniruddha B.

    2014-01-01

    Context: Research methodology in traditional Indian system of medicine. Aim: To determine the knowledge level of investigators conducting clinical trials in traditional medicines (TMs) including Ayurveda. Materials and Methods: This was a questionnaire survey conducted for selected researchers trained in any specialty and working in TM. 2087 researchers were selected based on selection criteria. A validated and pretested questionnaire containing the questions regarding regulatory issues, literature search, evidence-based medicine, clinical trial design, patient selection, and study reporting were sent either through E-mail or post. The answered questionnaires were analyzed. The parameters were analyzed based on median and interquartile range (IQR). Results: Forty two responses were received through E-mail and 21 researchers responded through post. Out of 63, six researchers sent incomplete responses. Among the remaining 57 respondents; 34 (59.6%) investigators had postdoctoral degree, 43 investigators (75.4%) did not receive any structured training on research methodology, 23 (40.4%) had two decades of research experience. Thirty three (74%) of investigators who received government funding didn’t have any training on research methodology. Ayurveda experts group had better knowledge compared to pharmaceutical sciences and basic science group although they had a dilemma about conducting clinical evaluation of TM within the specific framework of rigorous clinical pharmacological principles without ignoring the Ayurvedic concepts such as Dosha, Prakruti etc., Investigators below 30 years possessed higher knowledge of research methodology when analyzed based on the age. The respondents working in research organizations, government organizations, and academic institutions had lower knowledge compared to those who were in private organizations/practice. Conclusions: It is recommend that investigators, peer reviewers, and fund managers involved in traditional medicine

  8. Closing the Gender Gap in Technical Disciplines: AN Investigative Study

    NASA Astrophysics Data System (ADS)

    Gokhale, Anu A.; Stier, Ken

    The goal of this study was to investigate the efficacy of curriculum and instructional techniques in a technical core course to create a more conducive learning environment for women. The technical core course introduced technology majors to mechanical systems, electronics, and fluid power principles through lectures and laboratory work. Female students already enrolled in the department and female alumnae of the program were surveyed. The students' responses to the survey showed that although the female participants in the study were pleased with the instructors, the curriculum, and the instruction they received, they had recommendations for modifying the instruction.

  9. Food additives

    MedlinePlus

    Food additives are substances that become part of a food product when they are added during the processing or making of that food. "Direct" food additives are often added during processing to: Add nutrients ...

  10. Guest Investigator Studies with the Compton Gamma Ray Observatory

    NASA Astrophysics Data System (ADS)

    Vestrand, W. T.

    1998-09-01

    The cumulative all-sky survey by the Compton Gamma Ray Observatory (CGRO), composed of data acquired during the first three years of the mission, included a number of regions of very limited exposure. The most glaring deficiency in coverage was toward the region of the South Galactic Pole (SGP), which received significantly less exposure than other directions- by a factor of at least 2 to 3. Furthermore, nearly all of the SGP exposure was accumulated during the first year of the mission. Since blazars are known to be time-variable, and of unknown duty cycle, a pointing of the CCRO in that direction was considered highly desirable, and long overdue. In addition, data gathered from a pointing toward the SGP and its comparison with comprehensive data available for the North Galactic Pole would be extremely valuable to investigators studying the extragalactic diffuse emission. The reasons outlined above prompted our initiation of a Cycle 4 campaign to systematically search with EGRET and COMPTEL for gamma-ray emission from sources near the South Galactic Pole. The Cycle 4 SGP campaign consisted of tnvo 14-day observations separated in in time by approximately 10 months. The temporal separation of the observations was requested to allow a test for possible variations in the detected sources. Our primary targets were 38 FSRQs which lie within 30 degrees of the SGP, and which satisfy the basic criteria for candidate gamma-ray AGNs,flat-spectrum radio sources, many of which exhibit blazar-type properties). These targets were selected from the standard references, and from the available on-line databases (e.g., the NASA Extragalactic Database, NED), as the most promising AGN targets in the vicinity of the SGP. A 30 radius from the SGP was chosen as the boundary of our survey, since the selected targets would then fall within the most sensitive portion of the fields of view of EGRET and COMPTEL (i.e., within a 30 zenith angle), for a CGRO pointing directed exactly at the SGP

  11. Guest Investigator Studies with the Compton Gamma Ray Observatory

    NASA Technical Reports Server (NTRS)

    Vestrand, W. T.

    1998-01-01

    The cumulative all-sky survey by the Compton Gamma Ray Observatory (CGRO), composed of data acquired during the first three years of the mission, included a number of regions of very limited exposure. The most glaring deficiency in coverage was toward the region of the South Galactic Pole (SGP), which received significantly less exposure than other directions- by a factor of at least 2 to 3. Furthermore, nearly all of the SGP exposure was accumulated during the first year of the mission. Since blazars are known to be time-variable, and of unknown duty cycle, a pointing of the CCRO in that direction was considered highly desirable, and long overdue. In addition, data gathered from a pointing toward the SGP and its comparison with comprehensive data available for the North Galactic Pole would be extremely valuable to investigators studying the extragalactic diffuse emission. The reasons outlined above prompted our initiation of a Cycle 4 campaign to systematically search with EGRET and COMPTEL for gamma-ray emission from sources near the South Galactic Pole. The Cycle 4 SGP campaign consisted of tnvo 14-day observations separated in in time by approximately 10 months. The temporal separation of the observations was requested to allow a test for possible variations in the detected sources. Our primary targets were 38 FSRQs which lie within 30 degrees of the SGP, and which satisfy the basic criteria for candidate gamma-ray AGNs,flat-spectrum radio sources, many of which exhibit blazar-type properties). These targets were selected from the standard references, and from the available on-line databases (e.g., the NASA Extragalactic Database, NED), as the most promising AGN targets in the vicinity of the SGP. A 30 radius from the SGP was chosen as the boundary of our survey, since the selected targets would then fall within the most sensitive portion of the fields of view of EGRET and COMPTEL (i.e., within a 30 zenith angle), for a CGRO pointing directed exactly at the SGP

  12. Additional Study of Water Droplet Median Volume Diameter (MVD) Effects on Ice Shapes

    NASA Technical Reports Server (NTRS)

    Tsao, Jen-Ching; Anderson, David N.

    2005-01-01

    This paper reports the result of an experimental study in the NASA Glenn Icing Research Tunnel (IRT) to evaluate how well the MVD-independent effect identified previously might apply to SLD conditions in rime icing situations. Models were NACA 0012 wing sections with chords of 53.3 and 91.4 cm. Tests were conducted with a nominal airspeed of 77 m/s (150 kt) and a number of MVD's ranging from 15 to 100 m with LWC of 0.5 to 1 g/cu m. In the present study, ice shapes recorded from past studies and recent results at SLD and Appendix-C conditions are reviewed to show that droplet diameter is not important to rime ice shape for MVD of 30 microns or larger, but for less than 30 m drop sizes a rime ice shape transition from convex to wedge to spearhead type ice shape is observed.

  13. A Study of the Effect of Additional Reading Assistance on Student Achievement

    ERIC Educational Resources Information Center

    Gillan-Sanderson, Nicole A.

    2012-01-01

    This study describes a procedure one school district used to increase students' reading abilities through reviewing data and adjusting the instruction to give students intensive services, as needed. This school worked in a problem-solving team approach to develop a comprehensive team that followed the progression of student achievement.…

  14. Genome-Wide Association Study of Intelligence: Additive Effects of Novel Brain Expressed Genes

    ERIC Educational Resources Information Center

    Loo, Sandra K.; Shtir, Corina; Doyle, Alysa E.; Mick, Eric; McGough, James J.; McCracken, James; Biederman, Joseph; Smalley, Susan L.; Cantor, Rita M.; Faraone, Stephen V.; Nelson, Stanley F.

    2012-01-01

    Objective: The purpose of the present study was to identify common genetic variants that are associated with human intelligence or general cognitive ability. Method: We performed a genome-wide association analysis with a dense set of 1 million single-nucleotide polymorphisms (SNPs) and quantitative intelligence scores within an ancestrally…

  15. Nahuatl as a Classical, Foreign, and Additional Language: A Phenomenological Study

    ERIC Educational Resources Information Center

    De Felice, Dustin

    2012-01-01

    In this study, participants learning an endangered language variety shared their experiences, thoughts, and feelings about the often complex and diverse language-learning process. I used phenomenological interviews in order to learn more about these English or Spanish language speakers' journey with the Nahuatl language. From first encounter to…

  16. CNV-based genome wide association study reveals additional variants contributing to meat quality in swine

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pork quality is important both to the meat processing industry and consumers’ purchasing attitudes. Copy number variation (CNV) is a burgeoning kind of variant that may influence meat quality. Herein, a genome-wide association study (GWAS) was performed between CNVs and meat quality traits in swine....

  17. Ionoluminescence study of Zn- and O- implanted ZnO crystals: An additional perspective

    NASA Astrophysics Data System (ADS)

    Epie, E. N.; Chu, W. K.

    2016-05-01

    An investigation into the role of native point defects on the optical properties of ZnO using ion implantation, rapid thermal annealing (RTA) and ionoluminescence (IL) is presented. Low-energy (60 keV) fixed-fluence (8 × 1015 cm-2) Zn- and O- implantation has been used to directly introduce native point defects into ZnO single crystals. It is shown that annealing of implanted samples in Ar at T = 1000 °C for 2 min amplifies the deep band emission (DBE) peak centered around 2.4 eV while at the same time revealing subtle differences not clearly resolved in similar implanted samples treated under prolonged annealing. Particularly, a relative shift in the DBE peak maxima of the O and Zn doped samples subjected to RTA is observed. Gaussian decomposition of the IL spectra show distinct enhancements of the red (1.62 eV) and yellow (2.15 eV) emission bands in the O- implanted sample and the green (2.36 eV) emission band in the Zn- implanted sample. Based on these results, and recent density functional theory (DFT) calculations, we have proposed a possible energy level scheme for some common ZnO native point defects.

  18. Structural and rate studies of the 1,2-additions of lithium phenylacetylide to lithiated quinazolinones: influence of mixed aggregates on the reaction mechanism.

    PubMed

    Briggs, Timothy F; Winemiller, Mark D; Collum, David B; Parsons, Rodney L; Davulcu, Akin H; Harris, Gregory D; Fortunak, Joseph M; Confalone, Pat N

    2004-05-01

    The 1,2-addition of lithium phenylacetylide (PhCCLi) to quinazolinones was investigated using a combination of structural and rate studies. (6)Li, (13)C, and (19)F NMR spectroscopies show that deprotonation of quinazolinones and phenylacetylene in THF/pentane solutions with lithium hexamethyldisilazide affords a mixture of lithium quinazolinide/PhCCLi mixed dimer and mixed tetramer along with PhCCLi dimer. Although the mixed tetramer dominates at high mixed aggregate concentrations and low temperatures used for the structural studies, the mixed dimer is the dominant form at the low total mixed aggregate concentrations, high THF concentrations, and ambient temperatures used to investigate the 1,2-addition. Monitoring the reaction rates using (19)F NMR spectroscopy revealed a first-order dependence on mixed dimer, a zeroth-order dependence on THF, and a half-order dependence on the PhCCLi concentration. The rate law is consistent with the addition of a disolvated PhCCLi monomer to the mixed dimer. Investigation of the 1,2-addition of PhCCLi to an O-protected quinazolinone implicates reaction via trisolvated PhCCLi monomers. PMID:15113214

  19. Effect of Ni and Pd Addition on Mechanical, Thermodynamic, and Electronic Properties of AuSn4-Based Intermetallics: A Density Functional Investigation

    NASA Astrophysics Data System (ADS)

    Tian, Yali; Zhou, Wei; Wu, Ping

    2016-05-01

    The effects of Ni and Pd addition on the mechanical, thermodynamic, and electronic properties of AuSn4-based intermetallic compounds (IMCs) have been investigated by first-principles calculations to reveal the essence of Au embrittlement. Three kinds of doped (namely Ni-doped, Pd-doped, and Ni/Pd-codoped) IMCs are considered in this work. The polycrystalline elastic properties are deduced from single-crystal elastic constants. It is found that the doped systems together with nondoped AuSn4 are all ductile phases. For Ni-doped AuSn4, the modulus, hardness, brittleness, Debye temperature, and minimum thermal conductivity increase with the Ni fraction, but this is not the case for the Pd-doped material, since Au0.75Pd0.25Sn4 is the more brittle phase. For Au0.5Pd0.25Ni0.25Sn4, the mechanical, thermodynamic, and electronic properties are similar to those of Au0.5Pd0.5Sn4.

  20. Effect of Ni and Pd Addition on Mechanical, Thermodynamic, and Electronic Properties of AuSn4-Based Intermetallics: A Density Functional Investigation

    NASA Astrophysics Data System (ADS)

    Tian, Yali; Zhou, Wei; Wu, Ping

    2016-08-01

    The effects of Ni and Pd addition on the mechanical, thermodynamic, and electronic properties of AuSn4-based intermetallic compounds (IMCs) have been investigated by first-principles calculations to reveal the essence of Au embrittlement. Three kinds of doped (namely Ni-doped, Pd-doped, and Ni/Pd-codoped) IMCs are considered in this work. The polycrystalline elastic properties are deduced from single-crystal elastic constants. It is found that the doped systems together with nondoped AuSn4 are all ductile phases. For Ni-doped AuSn4, the modulus, hardness, brittleness, Debye temperature, and minimum thermal conductivity increase with the Ni fraction, but this is not the case for the Pd-doped material, since Au0.75Pd0.25Sn4 is the more brittle phase. For Au0.5Pd0.25Ni0.25Sn4, the mechanical, thermodynamic, and electronic properties are similar to those of Au0.5Pd0.5Sn4.

  1. Food additives

    PubMed Central

    Spencer, Michael

    1974-01-01

    Food additives are discussed from the food technology point of view. The reasons for their use are summarized: (1) to protect food from chemical and microbiological attack; (2) to even out seasonal supplies; (3) to improve their eating quality; (4) to improve their nutritional value. The various types of food additives are considered, e.g. colours, flavours, emulsifiers, bread and flour additives, preservatives, and nutritional additives. The paper concludes with consideration of those circumstances in which the use of additives is (a) justified and (b) unjustified. PMID:4467857

  2. Comparative study of glycine single crystals with additive of potassium nitrate in different concentration ratios

    NASA Astrophysics Data System (ADS)

    Gujarati, Vivek P.; Deshpande, M. P.; Patel, Kamakshi R.; Chaki, S. H.

    2016-05-01

    Semi-organic crystals of Glycine Potassium Nitrate (GPN) with potential applications in Non linear optics (NLO) were grown using slow evaporation technique. Glycine and Potassium Nitrate were taken in three different concentration ratios of 3:1, 2:1 and 1:1 respectively. We checked the solubility of the material in distilled water at different temperatures and could observe the growth of crystals in 7 weeks time. Purity of the grown crystals was confirmed by Energy Dispersive X-ray Analysis (EDAX) and CHN analysis. GSN Powder X-ray diffraction pattern was recorded to confirm the crystalline nature. To confirm the applications of grown crystals in opto-electronics field, UV-Vis-NIR study was carried out. Dielectric properties of the samples were studied in between the frequency range 1Hz to 100 KHz.

  3. Brief reconnaissance study for the addition of hydropower for Riegel Dam, Trion, Georgia

    SciTech Connect

    Gebhard, T.G. Jr.

    1982-05-10

    The feasibility of retrofitting the Riegel Dam near Trion, Georgia for power generation was examined. This dam has a developable head of 17 ft., was built in 1900 for supplying hydroelectric power for a textile mill, and currently provides cooling water to the mill. The study of environmental, institutional, safety and economic factors showed that hydroelectric power development at this site would require new generating equipment and that such retrofitting appears to be economically feasible. (LCL)

  4. Brief reconnaissance study for the addition of hydropower for Carr Fork Dam, Sassafras, Kentucky

    SciTech Connect

    Gebhard, T.G. Jr.

    1982-05-24

    The feasibility of retrofitting the Carr Fork Dam near Hazard, KY for power generation was examined. This dam has a developable head of 80 ft and was built in 1975 to provide flood protection. The study of environmental, institutional, safety, and economic factors showed that the total investment cost would be $909,600 and that hydroelectric power development at this site is not feasible unless a higher price could be obtained for the power sold. (LCL)

  5. Additional Studies of the Criticality Safety of Failed Used Nuclear Fuel

    SciTech Connect

    Marshall, William BJ J; Wagner, John C

    2013-01-01

    Commercial used nuclear fuel (UNF) in the United States is expected to remain in storage for periods potentially greater than 40 years. Extended storage (ES) time and irradiation to high-burnup values (>45 GWd/t) may increase the potential for fuel failure during normal and accident conditions involving storage and transportation. Fuel failure, depending on the severity, could result in changes to the geometric configuration of the fuel, which has safety and regulatory implications. The likelihood and extent of fuel reconfiguration and its impact on the safety of the UNF is not well understood. The objective of this work is to assess and quantify the impact of fuel reconfiguration due to fuel failure on criticality safety of UNF in storage and transportation casks. Criticality analyses are conducted considering representative UNF designs covering a range of enrichments and burnups in multiple cask systems. Prior work developed a set of failed fuel configuration categories and specific configurations were evaluated to understand trends and quantify the consequences of worst-case potential reconfiguration progressions. These results will be summarized here and indicate that the potential impacts on subcriticality can be rather significant for certain configurations (e.g., >20% keff). It can be concluded that the consequences of credible fuel failure configurations from ES or transportation following ES are manageable (e.g., <5% keff). The current work expands on these efforts and examines some modified scenarios and modified approaches to investigate the effectiveness of some techniques for reducing the calculated increase in keff. The areas included here are more realistic modeling of some assembly types and the effect of reconfiguration of some assemblies in the storage and transportation canister.

  6. A clinical comparative study of Cadiax Compact II and intraoral records using wax and addition silicone.

    PubMed

    Torabi, Kianoosh; Pour, Sasan Rasaei; Ahangari, Ahmad Hassan; Ghodsi, Safoura

    2014-01-01

    Evaluation of mandibular movements is necessary to form the occlusal anatomical contour, analyze the temporomandibular joint status, and evaluate the patient's occlusion. This clinical study was conducted to compare the mandibular recording device Cadiax Compact II with routine intraoral records for measuring condylar inclinations. The results showed that the differences between Cadiax and intraoral records were statistically significant for all measurements. Cadiax measurements had a stronger correlation with silicone records. The quantities of recorded Bennett angles were lower and the values of sagittal condylar inclination were higher with Cadiax than with routine intraoral records. PMID:25390868

  7. [Chewing gum as an additional agent in maintaining oral hygiene versus smoking status--preliminary study].

    PubMed

    Nakonieczna-Rudnicka, Marta; Strycharz-Dudziak, Małgorzata; Bachanek, Teresa

    2012-01-01

    Nowadays chewing gum is widely used in different age groups, so complying with proper duration and frequency of chewing is an important factor influencing the state of masticatory system. The study involved 112 dental students of the Medical University of Lublin. Everyday use of chewing gum declared 47,32% of cases. Chewing time up to 10 minutes was stated in 23,08% of respondents, 11-20 minutes in 40,38% of interviewees. Among the examined students 17,3% smoked cigarettes. In smokers group 83,33% of questioned chewed the gum every day, while among non-smokers - 43,37%. Chewing time shorter than 10 minutes declared 22,22% of smokers and 23,26% of non-smokers, while chewing time between 11-20 minutes - 27,78% i 44,35% of smokers and non-smokers respectively. Obtained results indicate the need of carrying out further studies aimed at the nicotine influence on saliva parameters with respect to development of diseases of hard tooth tissues. PMID:23421028

  8. Combined ab initio molecular dynamics and experimental studies of carbon atom addition to benzene.

    PubMed

    McKee, Michael L; Reisenauer, Hans Peter; Schreiner, Peter R

    2014-04-17

    Car-Parrinello molecular dynamics was used to explore the reactions between triplet and singlet carbon atoms with benzene. The computations reveal that, in the singlet C atom reaction, products are very exothermic where nearly every collision yields a product that is determined by the initial encounter geometry. The singlet C atom reaction does not follow the minimum energy path because the bimolecular reaction is controlled by dynamics (i.e., initial orientation of encounter). On the other hand, in a 10 K solid Ar matrix, ground state C((3)P) atoms do tend to follow RRKM kinetics. Thus, ab initio molecular dynamics (AIMD) results indicate that a significant fraction of C-H insertion occurs to form phenylcarbene whereas, in marked contrast to previous theoretical and experimental conclusions, the Ar matrix isolation studies indicate a large fraction of direct cycloheptatetraene formation, without the intermediacy of phenylcarbene. The AIMD calculations are more consistent with vaporized carbon atom experiments where labeling studies indicate the initial formation of phenylcarbene. This underlines that the availability of thermodynamic sinks can completely alter the observed reaction dynamics. PMID:24661002

  9. Shelf Life and Quality Study of Minced Tilapia with Nori and Hijiki Seaweeds as Natural Additives

    PubMed Central

    Ribeiro, Ingridy Simone; Shirahigue, Ligianne Din; Ferraz de Arruda Sucasas, Lia; Anbe, Lika; da Cruz, Pedro Gomes; Gallo, Cláudio Rosa; Carpes, Solange Teresinha; Marques, Marcos José; Oetterer, Marília

    2014-01-01

    The extraction of mechanically separated meat has emerged as an attractive process. However, it increases the incorporation of oxygen and, consequently, of flavors due to rancidity. Thus, preservatives must be added. The objective of this study was to evaluate the shelf life of minced tilapia to replace synthetic preservatives with Hijiki and Nori seaweeds extracts. The application of the extracts had no effect on the chemical composition of the minced tilapia. The seaweed extracts had inhibitory effect on total volatile base nitrogen. The minced tilapia complied with the microbiological standard set by Brazilin law. The panelists detected no differences in the rancid aroma and only minor differences were detected in the color of the products. It can be concluded that the minced tilapia with added seaweed extracts were within quality standards during frozen storage. PMID:25478593

  10. Shelf life and quality study of minced tilapia with Nori and Hijiki seaweeds as natural additives.

    PubMed

    Ribeiro, Ingridy Simone; Shirahigue, Ligianne Din; Ferraz de Arruda Sucasas, Lia; Anbe, Lika; da Cruz, Pedro Gomes; Gallo, Cláudio Rosa; Carpes, Solange Teresinha; Marques, Marcos José; Oetterer, Marília

    2014-01-01

    The extraction of mechanically separated meat has emerged as an attractive process. However, it increases the incorporation of oxygen and, consequently, of flavors due to rancidity. Thus, preservatives must be added. The objective of this study was to evaluate the shelf life of minced tilapia to replace synthetic preservatives with Hijiki and Nori seaweeds extracts. The application of the extracts had no effect on the chemical composition of the minced tilapia. The seaweed extracts had inhibitory effect on total volatile base nitrogen. The minced tilapia complied with the microbiological standard set by Brazilin law. The panelists detected no differences in the rancid aroma and only minor differences were detected in the color of the products. It can be concluded that the minced tilapia with added seaweed extracts were within quality standards during frozen storage. PMID:25478593

  11. l-carnitine as a Potential Additive in Blood Storage Solutions: A Study on Erythrocytes.

    PubMed

    Soumya, R; Carl, H; Vani, R

    2016-09-01

    Erythrocytes undergo various changes during storage (storage lesion) that in turn reduces their functioning and survival. Oxidative stress plays a major role in the storage lesion and antioxidants can be used to combat this stress. This study elucidates the effects of l-carnitine (LC) on erythrocytes of stored blood. Blood was obtained from male Wistar rats and stored (4 °C) for 20 days in CPDA-1 (citrate phosphate dextrose adenine) solution. Samples were divided into-(i) controls (ii) LC 10 (l-carnitine at a concentration of 10 mM) (iii) LC 30 (l-carnitine at a concentration of 30 mM) and (iv) LC 60 (l-carnitine at a concentration of 60 mM). Every fifth day, the biomarkers (haemoglobin, hemolysis, antioxidant enzymes, lipid peroxidation and protein oxidation products) were analysed in erythrocytes. Hemoglobin and protein sulfhydryls were insignificant during storage indicative of the maintenance of hemoglobin and sulfhydryls in all groups. Superoxide dismutase and malondialdehyde levels increased initially and decreased towards the end of storage. The levels of catalase and glutathione peroxidase were lower in experimentals than controls during storage. l-carnitine assisted the enzymes by scavenging the reactive oxygen species produced. Hemolysis increased in all groups with storage, elucidating that l-carnitine could not completely protect lipids and proteins from oxidative stress. Hence, this study opens up new avenues of using l-carnitine as a component of storage solutions with combinations of antioxidants in order to maintain efficacy of erythrocytes. PMID:27429526

  12. A digital process for additive manufacturing of occlusal splints: a clinical pilot study.

    PubMed

    Salmi, Mika; Paloheimo, Kaija-Stiina; Tuomi, Jukka; Ingman, Tuula; Mäkitie, Antti

    2013-07-01

    The aim of this study was to develop and evaluate a digital process for manufacturing of occlusal splints. An alginate impression was taken from the upper and lower jaws of a patient with temporomandibular disorder owing to cross bite and wear of the teeth, and then digitized using a table laser scanner. The scanned model was repaired using the 3Data Expert software, and a splint was designed with the Viscam RP software. A splint was manufactured from a biocompatible liquid photopolymer by stereolithography. The system employed in the process was SLA 350. The splint was worn nightly for six months. The patient adapted to the splint well and found it comfortable to use. The splint relieved tension in the patient's bite muscles. No sign of tooth wear or significant splint wear was detected after six months of testing. Modern digital technology enables us to manufacture clinically functional occlusal splints, which might reduce costs, dental technician working time and chair-side time. Maximum-dimensional errors of approximately 1 mm were found at thin walls and sharp corners of the splint when compared with the digital model. PMID:23614943

  13. A digital process for additive manufacturing of occlusal splints: a clinical pilot study

    PubMed Central

    Salmi, Mika; Paloheimo, Kaija-Stiina; Tuomi, Jukka; Ingman, Tuula; Mäkitie, Antti

    2013-01-01

    The aim of this study was to develop and evaluate a digital process for manufacturing of occlusal splints. An alginate impression was taken from the upper and lower jaws of a patient with temporomandibular disorder owing to cross bite and wear of the teeth, and then digitized using a table laser scanner. The scanned model was repaired using the 3Data Expert software, and a splint was designed with the Viscam RP software. A splint was manufactured from a biocompatible liquid photopolymer by stereolithography. The system employed in the process was SLA 350. The splint was worn nightly for six months. The patient adapted to the splint well and found it comfortable to use. The splint relieved tension in the patient's bite muscles. No sign of tooth wear or significant splint wear was detected after six months of testing. Modern digital technology enables us to manufacture clinically functional occlusal splints, which might reduce costs, dental technician working time and chair-side time. Maximum-dimensional errors of approximately 1 mm were found at thin walls and sharp corners of the splint when compared with the digital model. PMID:23614943

  14. Value addition of Palmyra palm and studies on the storage life.

    PubMed

    Chaurasiya, A K; Chakraborty, I; Saha, J

    2014-04-01

    Palmyra palm (Borassus flabellifer L.) belonging to the family Palmae is referred to as tree of life with several uses including food, beverage, fibre, medicinal and timber. Unfortunately, the nutritionally enriched pulp of ripened palm has limited commercial use. Extraction of pulp has been accomplished by using water and heat to ensure maximum pulp recovery. Different recipes were tried for the preparation of two uncommon value added products like palm spread and palm toffee. On the basis of biochemical composition, organoleptic scores, microbial estimation and storage study both under ambient and refrigerated conditions; the suitable recipe was selected with the maximum acceptability. Gradual increase in total soluble solid (TSS), total sugar and reducing sugar while decrease in ascorbic acid, pH, β-carotene and protein content of processed products have been observed irrespective of storage condition. The results obtained from sensory evaluation and microbial status revealed that palm spread and toffee remained acceptable up to 9 months and 8 months, respectively at ambient temperature. The income per rupee investment for these two products was found to be remunerative. PMID:24741173

  15. Mass analysis addition to the Differential Ion Flux Probe (DIFP) study

    NASA Technical Reports Server (NTRS)

    Wright, K. H., Jr.; Jolley, Richard

    1994-01-01

    The objective of this study is to develop a technique to measure the characteristics of space plasmas under highly disturbed conditions; e.g., non-Maxwellian plasmas with strong drifting populations and plasmas contaminated by spacecraft outgassing. The approach, conducted in conjunction with current MSFC activities, is to extend the capabilities of the Differential Ion Flux Probe (DIFP) to include a high throughput mass measurement that does not require either high voltage or contamination sensitive devices such as channeltron electron multipliers or microchannel plates. This will significantly reduce the complexity and expense of instrument fabrication, testing, and integration of flight hardware compared to classical mass analyzers. The feasibility of the enhanced DIFP has been verified by using breadboard test models in a controlled plasma environment. The ability to manipulate particles through the instrument regardless of incident angle, energy, or ionic component has been amply demonstrated. The energy analysis mode is differential and leads directly to a time-of-flight mass measurement. With the new design, the DIFP will separate multiple ion streams and analyze each stream independently for ion flux intensity, velocity (including direction of motion), mass, and temperature (or energy distribution). In particular, such an instrument will be invaluable on follow-on electrodynamic TSS missions and, possibly, for environmental monitoring on the space station.

  16. CCD Photometric Study and Period Investigation of AH Tauri

    NASA Astrophysics Data System (ADS)

    Xiang, Fu-Yuan; Xiao, Ting-Yu; Yu, Yun-Xia

    2015-07-01

    In this paper, we present new CCD photometric observations of AH Tauri in the R band observed in 2006 at the Yunnan Observatory. Two new times of light minima were derived from these observations. We modeled the light curves using the 2003 version of the Wilson-Devinney program. The results show that the variations of the light curves can be expained by a cool spot on the primary star. The fill-out factor is about 6.6%, indicating that AH Tauri is a shallow-contact system. The mass ratio was determined to be about 0.505. In addition, the orbital period variations of AH Tauri were investigated based on all of the photoelectric and CCD light minimum times, including our two new data. It was found that the orbital period exhibits a possible periodic variation with a period of {P}{mod}=54.62\\(+/- 0.20) years and a secular period decrease of {dP}/{dt}=-(1.823+/- 0.215)× {10}-7 {days} {{yr}}-1. Since AH Tauri is an overcontact solar-like system, we discuss three mechanisms of the mass transfer, the light-time effect of the third body, and magnetic activity responsible for the orbital period changes.

  17. Studying the effect of nano lead compounds additives on the concrete shielding properties for γ-rays

    NASA Astrophysics Data System (ADS)

    Hassan, H. E.; Badran, H. M.; Aydarous, A.; Sharshar, T.

    2015-10-01

    In the present work the effect of concrete incorporation with two types of nano-lead compounds on its γ-ray shielding characteristics is investigated. The concrete samples were prepared according to the local standards of building materials and doped by different percentages of PbO and PbTiO3 nano powders which were prepared using co-precipitation and oxalate precursor techniques, respectively. In addition, commercial PbO2 powder additive was used to check the effect of particle size on concrete attenuation properties. The phase composition and particle size of all the lead-oxide additives were confirmed by XRD and TEM imaging. The γ-rays attenuation coefficients were measured as a function of the additive percentage of lead compounds for γ-ray energies of 662, 1173 and 1332 keV using 137Cs and 60Co sources. The microstructure changes occurred in the concrete samples doped with Pb compounds additives were probed using the positron annihilation spectroscopy (PAS) and the results were compared with that for normal concrete. The obtained data revealed that the overall defect density of the investigated samples, as seen by the positrons, decreases with increasing the nano-PbO contents which is in agreement with the determined values of the samples apparent densities. It was found that the γ-ray attenuation coefficient of concrete doped by nano-PbO is improved. The results are explained in the view of the fine structure enhanced modification and its impact on the γ-ray interaction probability at different energies.

  18. Neurobehavioral deficits in Persian Gulf veterans: additional evidence from a population-based study.

    PubMed

    Storzbach, D; Rohlman, D S; Anger, W K; Binder, L M; Campbell, K A

    2001-01-01

    Reports of low-concentration nerve gas exposures during the Gulf War (GW) have spurred concern about possible health consequences and symptoms reported by many returning veterans. The Portland Environmental Hazards Research Center is studying veterans from the northwest United States who report persistent, unexplained "Gulf War" symptoms (cases) and those who do not report those symptoms (controls). An epidemiological survey focused on exposures and symptoms was mailed to a random sample of GW veterans from Oregon and southwestern Washington. Volunteers recruited from survey respondents agreed to undergo a thorough medical examination and psychological and neurobehavioral assessment. Persistent symptoms with no medical explanation associated with Persian Gulf service (e.g., fatigue, muscle pain, memory deficits) beginning during or after the war qualified respondents as cases. The 239 cases with unexplained symptoms and the 112 controls without symptoms were administered a computerized assessment battery of 12 psychosocial and 6 neurobehavioral tests. Replicating and extending previous interim findings, a subgroup of veterans emerged from the initial analysis in the form of extreme outliers which produced a visually and quantitatively obvious bimodal distribution. This led, as it had previously, to analyses of the outliers as a separate group (labeled "slow ODTP"), which confirmed the initial findings of neurobehavioral differences between the outliers and the other cases and controls and provided more convincing evidence that the majority of cases who report neurobehavioral symptoms have no objective evidence of neurobehavioral deficits. However, the larger group of symptomatic veterans do have highly significant and compelling evidence of psychological distress based on scores from 11 separate psychological tests. Whereas the cases differed from the controls by poorer neurobehavioral test performance, extraction of the slow ODTP participants (almost all cases

  19. Phytochemical investigation and biological studies of Bombax malabaricum flowers.

    PubMed

    El-Hagrassi, Ali M; Ali, Mamdouh M; Osman, Abeer F; Shaaban, Mohamed

    2011-01-01

    In this study, extracts of the flowers of the folk medicinal plant Bombax malabaricum DC were biologically and chemically screened. Chemical constituents in the n-hexane fraction from the flowers of B. malabaricum DC were investigated using gas-liquid chromatography (GLC) analysis, affording 14 compounds, including cholesterol, stigmasterol, campesterol and α-amyrin, while the residual 10 compounds are hydrocarbons. GLC analysis of the fatty acid (FA) esters established the majority abundance of the saturated FA over their unsaturated analogues. The polar methanol fraction afforded seven flavones: vicenin 2 (1), linarin (2), saponarin (3), cosmetin (4), isovitexin (5), xanthomicrol (6) and apigenin (7). Structures 1-7 were established by intensive studies of various spectral data (H-NMR, mass spectroscopy and UV) and comparison with authentic samples. Compounds 1-7 are described here for the first time from this plant. Extracts of n-hexane and methanol exhibited significant antioxidant and antimicrobial activities. PMID:21246441

  20. A Pilot Study to Examine the Effect of Additional Structured Outdoor Playtime on Preschoolers' Physical Activity Levels

    ERIC Educational Resources Information Center

    Alhassan, Sofiya; Nwaokelemeh, Ogechi; Lyden, Kate; Goldsby, TaShauna; Mendoza, Albert

    2013-01-01

    The impact of additional structured outdoor playtime on preschoolers'; physical activity (PA) level is unclear. The purpose of this pilot study was to explore the effects of increasing structured outdoor playtime on preschoolers'; PA levels. Eight full-day classrooms (n = 134 children) from two preschool programmes were randomised into a treatment…

  1. STUDY OF THE EFFECT OF CHLORINE ADDITION ON MERCURY OXIDATION BY SCR CATALYST UNDER SIMULATED SUBBITUMINOUS COAL FLUE GAS

    EPA Science Inventory

    An entrained flow reactor is used to study the effect of addition of chlorine-containing species on the oxidation of elemental mercury (Hgo)by a selective catalytic reduction (SCR) catalyst in simulated subbituminous coal combustion flue gas. The combustion flue gas was doped wit...

  2. Investigation of Nucleation Bursts During the Pittsburgh Air Quality Study

    NASA Astrophysics Data System (ADS)

    Stanier, C. O.; Khlystov, A. Y.; Wittig, B.; Pandis, S. N.; Zhou, Y.; Bein, K.; Wexler, A. S.; Misra, C.; Sioutas, C.

    2002-12-01

    Homogeneous nucleation is one of the major sources of atmospheric particles on a global scale. Understanding nucleation is important for quantifying its role in shaping the ambient aerosol distribution and its effects on cloud properties and the planetary energy balance. Over 100 days with nucleation events were investigated during a sampling campaign sampling continental aerosols in Pittsburgh, Pennsylvania. Over 90,000 size distributions were collected over 12 months using Scanning Mobility Particle Sizers (SMPS) at three locations, including both urban and rural sites. Particle size distributions were measured down to 3 nm at the main site and to 10 nm at the other sites. The frequency of nucleation events was surprising. Approximately 50% of the study days were characterized by nucleation events. These events appear to occur over a large area and are not directly related to the emissions from the urban area. Some nucleation events occurred near simultaneously at samplers 500 km apart. Theories under investigation for the nucleation mechanism include sulfuric acid-water, sulfuric acid-water-ammonia, and secondary organic nucleation. The chemistry of the freshly nucleated and growing particles was investigated by collecting over 20,000 single particle mass spectra using Laser Ablation Aerosol Mass Spectrometry on particles as small as 20 nm. Results of TDMA and hygroscopic growth measurements of nuclei mode particles will also be presented. A large number of high-frequency gas, particle, and meteorological measurements were taken with collocated instruments. Data will be analyzed to elucidate possible cause-effect relationships and the dataset will be compared to theoretical estimates of nucleation rates for a number of mechanisms.

  3. Investigation on mechanical properties of basalt composite fabrics (experiment study)

    NASA Astrophysics Data System (ADS)

    Talebi Mazraehshahi, H.; Zamani, H.

    2010-06-01

    To fully appreciate the role and application of composite materials to structures, correct understanding of mechanical behaviors required for selection of optimum material. Fabric reinforced composites are composed of a matrix that is reinforced with pliable fabric, glass fabric is most popular reinforcement for different application specially in aircraft structure, although other fabric material are also used. At this study new fabric material called basalt with epoxy resin introduced and mechanical behaviors of this material investigated from view point of testing. For this study two type of fabric with different thickness used. Comparison between this composite reinforcement with popular reinforcement as carbon, glass, kevlar performed. To determine mechanical properties of epoxy based basalt fabric following test procedure performed : 1). Tensile testing according to ASTM D3039 in 0° and 90° direction to find ultimate strength in tension and shear, modulus of elasticity, elangation and ultimate strain. 2). Compression testing according to EN 2850 ultimate compression strength and maximum deformation under compression loading. 3). Shear testing according to ASTM D3518-94 to find in plane shear response of polymer matrix composites materials. 4). Predict flexural properties of sandwich construction which manufactured from basalt facing with PVC foam core according to ASTM C393-94. Material strength properties must be based on enough tests of material to meet the test procedure specifications [1]. For this reason six specimens were manufactured for testing and the tests were performed on them using an INSTRON machine model 5582. In the study, the effect of percent of resin in basalt reinforced composite was investigated. Also the weights of the ballast based composites with different percent of resin were measured with conventional composites. As the weight is an important parameter in aerospace industry when the designer wants to replace one material with

  4. Wellfield installation and investigations, Creston Study Area, Eastern Washington

    SciTech Connect

    Paschis, J.A.; Kunkel, J.R.; Koenig, R.A.

    1988-11-01

    The report summarizes the design and implementation of field testing used to characterize the Roza Member basalt aquifer of the Wanapum Formation of the Columbia River Basalt Group. A research wellfield was implemented and tests conducted to lithologically classify subsurface conditions underlying an 800- by 1400-foot area located in the northwest quarter of Section 16, T.25N, R.34E, six miles south of the town of Creston in Lincoln County, Washington. The relatively high-yielding aquifers of the Roza Member basalt are separated by claystone aquitards and are hydrologically interrupted by at least two different subsurface hydrologic structures. Water-level data were used to determine the regional and local hydraulic gradient. Wellbore slug tests and passive (nonpumping) tracer tests permitted calculation of equivalent hydraulic apertures and effective porosities for the Roza basalt flow top and flow interiors. Analysis of data from pumping tests permitted calculation of transmissivities and storage coefficients for the Roza basalt. Measurements of water level are continuing, and additional tracer tests have been conducted both in the wellfield proper and in the larger study area. Applicable wellfield aquifer analyses along with model studies will provide guidelines for use in evaluating proposed sites for disposing of high-level nuclear waste in saturated fractured geologic media. 36 refs., 72 figs., 16 tabs.

  5. Toxicological investigations on silicon carbide. 1. Inhalation studies.

    PubMed Central

    Bruch, J; Rehn, B; Song, H; Gono, E; Malkusch, W

    1993-01-01

    The question of lung damage as a result of exposure to silicon carbide (SiC) was investigated by inhalation experiments to obtain information on the qualitative response of lung tissue to the test substance (SiC). For comparison, quartz, kaolinite, and tempered clay dusts were used. The indices for the effects of the dusts studied were organ weights, numbers of bronchoalveolar cells, lung surfactant phospholipid concentrations including subfractions, and lung clearance. Exposure to the test samples was carried out according to the Essen inhalation model in two independent series. The results of the two series were similar: Compared with sham controls, exposure to SiC did not affect the indices studied. Even at a low dose (a quarter of the SiC dose) quartz gave pronounced deviations in all indices. In particular, an increase in granulocytes indicated toxic properties of the dust. The long term elimination of quartz from the lung was worse than that of SiC. The kaolinite and tempered clay dusts were intermediate between SiC and quartz based on several of the indices studied. It is concluded that SiC is deposited practically inert in the lung. PMID:8398873

  6. Organic additive, 5-methylsalicylic acid induces spontaneous structural transformation of aqueous pluronic triblock copolymer solution: a spectroscopic investigation of interaction of curcumin with pluronic micellar and vesicular aggregates.

    PubMed

    Ghosh, Surajit; Kuchlyan, Jagannath; Banik, Debasis; Kundu, Niloy; Roy, Arpita; Banerjee, Chiranjib; Sarkar, Nilmoni

    2014-10-01

    This article presents the interaction of curcumin in the microenvironments provided by aggregation of pluronic triblock copolymer P123 into micellar and vesicular assemblies. The formation of vesicles using triblock copolymer P123 and 5-methylsalicylic acid (5 mS) has been successfully characterized by optical spectroscopy, light scattering measurement, and eventually microscopic techniques. Besides, to make a comparative study between the polymeric micelles, we have also investigated the photophysical changes of curcumin in F127 triblock copolymer micelles having variation in poly(ethylene oxide) (PPO) and poly(propylene oxide) (PEO) unit of polymer chain to that of P123. Time-dependent UV-vis measurement suggests that these polymer micelles are able to stabilize poorly water-soluble curcumin by suppressing the degradation rate in micellar nanocavity. However, experimental observations suggest that P123 micelles are more efficient than F127 to perturb excited state intramolecular proton transfer (ESIPT)-related nonradiative decay of curcumin. We also observed that rigid and confined microenvironment of P123/5 mS vesicles enhances emission intensity and lifetime of curcumin more compared to P123 micelles. All the observations suggest that modulation of photophysics of curcumin is responsible due to its interaction with poly(ethylene oxide) or poly(propylene oxide) unit of triblock copolymer. PMID:25192258

  7. A study of internal structure in components made by additive manufacturing process using 3 D X-ray tomography

    NASA Astrophysics Data System (ADS)

    Raguvarun, K.; Balasubramaniam, Krishnan; Rajagopal, Prabhu; Palanisamy, Suresh; Nagarajah, Romesh; Hoye, Nicholas; Curiri, Dominic; Kapoor, Ajay

    2015-03-01

    Additive manufacturing methods are gaining increasing popularity for rapidly and efficiently manufacturing parts and components in the industrial context, as well as for domestic applications. However, except when used for prototyping or rapid visualization of components, industries are concerned with the load carrying capacity and strength achievable by additive manufactured parts. In this paper, the wire-arc additive manufacturing (AM) process based on gas tungsten arc welding (GTAW) has been examined for the internal structure and constitution of components generated by the process. High-resolution 3D X-ray tomography is used to gain cut-views through wedge-shaped parts created using this GTAW additive manufacturing process with titanium alloy materials. In this work, two different control conditions for the GTAW process are considered. The studies reveal clusters of porosities, located in periodic spatial intervals along the sample cross-section. Such internal defects can have a detrimental effect on the strength of the resulting AM components, as shown in destructive testing studies. Closer examination of this phenomenon shows that defect clusters are preferentially located at GTAW traversal path intervals. These results highlight the strong need for enhanced control of process parameters in ensuring components with minimal defects and higher strength.

  8. A study of internal structure in components made by additive manufacturing process using 3 D X-ray tomography

    SciTech Connect

    Raguvarun, K. Balasubramaniam, Krishnan Rajagopal, Prabhu; Palanisamy, Suresh; Nagarajah, Romesh; Kapoor, Ajay; Hoye, Nicholas; Curiri, Dominic

    2015-03-31

    Additive manufacturing methods are gaining increasing popularity for rapidly and efficiently manufacturing parts and components in the industrial context, as well as for domestic applications. However, except when used for prototyping or rapid visualization of components, industries are concerned with the load carrying capacity and strength achievable by additive manufactured parts. In this paper, the wire-arc additive manufacturing (AM) process based on gas tungsten arc welding (GTAW) has been examined for the internal structure and constitution of components generated by the process. High-resolution 3D X-ray tomography is used to gain cut-views through wedge-shaped parts created using this GTAW additive manufacturing process with titanium alloy materials. In this work, two different control conditions for the GTAW process are considered. The studies reveal clusters of porosities, located in periodic spatial intervals along the sample cross-section. Such internal defects can have a detrimental effect on the strength of the resulting AM components, as shown in destructive testing studies. Closer examination of this phenomenon shows that defect clusters are preferentially located at GTAW traversal path intervals. These results highlight the strong need for enhanced control of process parameters in ensuring components with minimal defects and higher strength.

  9. Studies on the effect of plasticiser and addition of toluene diisocyanate at different temperatures in composite propellant formulations.

    PubMed

    Jawalkar, S N; Mehilal; Ramesh, K; Radhakrishnan, K K; Bhattacharya, B

    2009-05-30

    Different composite propellant mixtures have been prepared using ammonium perchlorate, aluminium powder and hydroxyl terminated polybutadiene by varying the percentage of plasticiser and addition of toluene diisocyanate at different temperatures, and studied their different properties such as viscosity build-up, mechanical and ballistic properties and sensitivity. The data on different plasticiser level indicate that on decreasing the plasticiser content, there is a significant enhancement in end of mix viscosity, tensile strength and modulus while elongation decreases drastically. The data on sensitivity of the studied mixtures reveal that on decreasing the percentage of plasticiser, the sensitivity increases, accordingly. Further, the data on the effect of addition of TDI at different temperatures (35-60 degrees C) infer that on increasing the addition temperature of TDI there is a decrease in end of mix viscosity i.e. 800Pas at 35 degrees C to 448Pas at 60 degrees C. Moreover, there is no effect on mechanical and ballistic properties on higher temperature addition of TDI was observed. PMID:18835097

  10. Fibrinogen reduction and coagulation in cardiac surgery: an investigational study.

    PubMed

    Gielen, Chantal L I; Grimbergen, Jos; Klautz, Robert J M; Koopman, Jaap; Quax, Paul H A

    2015-09-01

    Fibrinogen as precursor of fibrin plays an essential role in clot formation. There are three main mechanisms associated with a reduction in fibrinogen concentration during cardiac surgery: hemodilution, consumption, and degradation. Moreover, early fibrinogen degradation products (FgDPs) can interfere with normal fibrin formation of intact fibrinogen. The aim of this study was to determine the relative contributions of hemodilution, consumption, and degradation to fibrinogen loss in cardiac surgery and to evaluate the effects fibrinogen degradation products on blood clot formation in vitro. First, fibrin and fibrinogen concentrations, their degradation products, hematocrit, and albumin concentrations were compared in 10 patients before and after isolated coronary artery bypass graft (CABG) surgery with cardiopulmonary bypass. Second, ex-vivo fibrinogen supplementation experiments were performed. Finally, the effects of purified FgDPs on clotting time and clot firmness were established in vitro in whole blood by ROTEM. Fibrinogen plasma concentration decreased 30% during surgery. This drop appears to be mainly caused by hemodilution, as both hematocrit and albumin levels decreased and no relevant increase in D-dimer levels and FgDPs was observed. Furthermore, the coagulation profile normalized after addition of purified fibrinogen. Early FgDPs demonstrated a significant impact on in-vitro whole blood clotting. Although early FgDPs have a pronounced effect on blood clot formation in vitro and therefore may induce or enhance in vivo coagulopathy, the drop of fibrinogen concentration seen after CABG surgery (using tranexamic acid) is primarily caused by hemodilution. PMID:26083991

  11. A theoretical study of the ozonolysis of C60: primary ozonide formation, dissociation, and multiple ozone additions.

    PubMed

    Chapleski, Robert C; Morris, John R; Troya, Diego

    2014-04-01

    We present an investigation of the reaction of ozone with C60 fullerene using electronic structure methods. Motivated by recent experiments of ozone exposure to a C60 film, we have characterized stationary points in the potential energy surface for the reactions of O3 with C60 that include both the formation of primary ozonide and subsequent dissociation reactions of this intermediate that lead to C-C bond cleavage. We have also investigated the addition of multiple O3 molecules to the C60 cage to explore potential reaction pathways under the high ozone flux conditions used in recent experiments. The lowest-energy product of the reaction of a single ozone molecule with C60 that results in C-C bond breakage corresponds to an open-cage C60O3 structure that contains ester and ketone moieties at the seam. This open-cage product is of much lower energy than the C60O + O2 products identified in prior work, and it is consistent with IR experimental spectra. Subsequent reaction of the open-cage C60O3 product with a second ozone molecule opens a low-energy reaction pathway that results in cage degradation via the loss of a CO2 molecule. Our calculations also reveal that, while full ozonation of all bonds between hexagons in C60 is unlikely even under high ozone concentration, the addition of a few ozone molecules to the C60 cage is favorable at room temperature. PMID:24549406

  12. Numerical study of water entry supercavitating flow around a vertical circular cylinder influenced by turbulent drag-reducing additives

    NASA Astrophysics Data System (ADS)

    Jiang, C. X.; Cheng, J. P.; Li, F. C.

    2015-01-01

    This paper attempts to introduce a numerical simulation procedure to simulate water-entry problems influenced by turbulent drag-reducing additives in a viscous incompressible medium. Firstly we performed a numerical investigation on water-entry supercavities in water and turbulent drag-reducing solution at the impact velocity of 28.4 m/s to confirm the accuracy of the numerical method. Based on the verification, projectile entering water and turbulent drag-reducing solution at relatively high velocity of 142.7 m/s (phase transition is considered) is simulated. The cross viscosity equation was adopted to represent the shear-thinning characteristic of aqueous solution of drag-reducing additives. The configuration and dynamic characteristics of water entry supercavity, flow resistance were discussed respectively. It was obtained that the numerical simulation results are in consistence with experimental data. Numerical results show that the supercavity length in drag-reducing solution is larger than one in water and the velocity attenuates faster at high velocity than at low velocity; the influence of drag-reducing solution is more obvious at high impact velocity. Turbulent drag-reducing additives have the great potential for enhancement of supercavity.

  13. Learning to Do Through Investigative Projects: A Case Study

    NASA Astrophysics Data System (ADS)

    Jolly, Pratibha

    2005-10-01

    In India, the likelihood of a girl student opting out of a physics course only because of gender issues is remote. Even though no special care is taken to attract women, a large percentage of the top-ranking students opt to major in physics. However, subtle forces operate in higher academia. The number of women in teaching and research institutes continues to be dismally low. The confidence and motivation of women students shows a distinct attenuation at the tertiary level. Inasmuch as the undergraduate years lay the foundation for a career in physics, there is a critical need to create learning experiences for women students that would enhance their motivation, nurture talent, and generate confidence in their capacity to make a creative contribution. The author has spent several years teaching at a women's college and in a university department with few women on the faculty. She has coordinated the Learning Through Investigative Projects program for undergraduate students of both genders. In a dual-pronged strategy, students are constructively engaged in open-ended investigative projects and assigned specific tasks. The touchstone of this program is the ambience in which the projects are carried out and the cognitive changes it effects in students as they are weaned away from the prevalent transmissionist mode of teaching and led to a constructivist paradigm of learning. They acquire an ability to work independently. The program and the underpinning pedagogic model have been very successful in capacity building and have influenced many students to choose careers in physics and academia. I present a case study of the work carried out under Project Science Online, in which students helped develop a microcomputer-based laboratory.

  14. Helping Students Soar to Success on Computers: An Investigation of the Soar Study Method for Computer-Based Learning

    ERIC Educational Resources Information Center

    Jairam, Dharmananda; Kiewra, Kenneth A.

    2010-01-01

    This study used self-report and observation techniques to investigate how students study computer-based materials. In addition, it examined if a study method called SOAR can facilitate computer-based learning. SOAR is an acronym that stands for the method's 4 theoretically driven and empirically supported components: select (S), organize (O),…

  15. Using a generalized additive model with autoregressive terms to study the effects of daily temperature on mortality

    PubMed Central

    2012-01-01

    Background Generalized Additive Model (GAM) provides a flexible and effective technique for modelling nonlinear time-series in studies of the health effects of environmental factors. However, GAM assumes that errors are mutually independent, while time series can be correlated in adjacent time points. Here, a GAM with Autoregressive terms (GAMAR) is introduced to fill this gap. Methods Parameters in GAMAR are estimated by maximum partial likelihood using modified Newton’s method, and the difference between GAM and GAMAR is demonstrated using two simulation studies and a real data example. GAMM is also compared to GAMAR in simulation study 1. Results In the simulation studies, the bias of the mean estimates from GAM and GAMAR are similar but GAMAR has better coverage and smaller relative error. While the results from GAMM are similar to GAMAR, the estimation procedure of GAMM is much slower than GAMAR. In the case study, the Pearson residuals from the GAM are correlated, while those from GAMAR are quite close to white noise. In addition, the estimates of the temperature effects are different between GAM and GAMAR. Conclusions GAMAR incorporates both explanatory variables and AR terms so it can quantify the nonlinear impact of environmental factors on health outcome as well as the serial correlation between the observations. It can be a useful tool in environmental epidemiological studies. PMID:23110601

  16. Microstructural Development and Technical Challenges in Laser Additive Manufacturing: Case Study with a 316L Industrial Part

    NASA Astrophysics Data System (ADS)

    Marya, Manuel; Singh, Virendra; Marya, Surendar; Hascoet, Jean Yves

    2015-08-01

    Additive manufacturing (AM) brings disruptive changes to the ways parts, and products are designed, fabricated, tested, qualified, inspected, marketed, and sold. These changes introduce novel technical challenges and concerns arising from the maturity and diversity of today's AM processes, feedstock materials, and process parameter interactions. AM bears a resemblance with laser and electron beam welding in the so-called conduction mode, which involves a multitude of dynamic physical events between the projected feedstock and a moving heat source that eventually influence AM part properties. For this paper, an air vent was selected for its thin-walled, hollow, and variable cross section, and limited size. The studied air vents, randomly selected from a qualification batch, were fabricated out of 316L stainless steel using a 4 kW fiber laser powder-fed AM system, referred to as construction laser additive direct (CLAD). These were systematically characterized by microhardness indentation, visual examination, optical and scanning electron microscopy, and electron-back-scattering diffraction in order to determine AM part suitability for service and also broadly discuss metallurgical phenomena. The paper then briefly expands the discussion to include additional engineering alloys and further analyze relationships between AM process parameters and AM part properties, consistently utilizing past experience with the same powder-fed CLAD 3D printer, the well-established science and technology of welding and joining, and recent publications on additive manufacturing.

  17. Experimental study of the subtalar joint axis: preliminary investigation.

    PubMed

    Zographos, S; Chaminade, B; Hobatho, M C; Utheza, G

    2000-01-01

    An experimental study of the subtalar joint has been conducted with the aim of establishing its axis of movement as well as analysing the associated movement. For description of the axis, CT data for five positions of a single foot were reconstructed using a 3D programme, the 3D data was processed by Patran software. Measures of angular displacements were made from three amputated feet placed in a specially constructed foot frame. Four instantaneous axes of movement could be defined. Calculation of displacements showed an important rolling of the calcaneus (45 degrees). Tacking was evident in inversion, with an opposite displacement between the front and rear part of the calcaneus, whereas during eversion tacking affected only the rear part of the bone: these results were confirmed by 3D reconstructions. Henke's axis was described as that for the talonavicular joint, but acceptable for the subtalar joint. Several authors investigating the coordinates of this axis have reported large differences and described screw-like movements, the latter being incompatible with a fixed axis: instantaneous axes, however are compatible with a screw-like movement. The subtalar joint appears to work as a pivot joint during inversion and as a plane joint during eversion. Although Henke's axis has pedagogical value the subtalar joint has a series of instantaneous axes. PMID:11236321

  18. Potlining Additives

    SciTech Connect

    Rudolf Keller

    2004-08-10

    In this project, a concept to improve the performance of aluminum production cells by introducing potlining additives was examined and tested. Boron oxide was added to cathode blocks, and titanium was dissolved in the metal pool; this resulted in the formation of titanium diboride and caused the molten aluminum to wet the carbonaceous cathode surface. Such wetting reportedly leads to operational improvements and extended cell life. In addition, boron oxide suppresses cyanide formation. This final report presents and discusses the results of this project. Substantial economic benefits for the practical implementation of the technology are projected, especially for modern cells with graphitized blocks. For example, with an energy savings of about 5% and an increase in pot life from 1500 to 2500 days, a cost savings of $ 0.023 per pound of aluminum produced is projected for a 200 kA pot.

  19. Phosphazene additives

    SciTech Connect

    Harrup, Mason K; Rollins, Harry W

    2013-11-26

    An additive comprising a phosphazene compound that has at least two reactive functional groups and at least one capping functional group bonded to phosphorus atoms of the phosphazene compound. One of the at least two reactive functional groups is configured to react with cellulose and the other of the at least two reactive functional groups is configured to react with a resin, such as an amine resin of a polycarboxylic acid resin. The at least one capping functional group is selected from the group consisting of a short chain ether group, an alkoxy group, or an aryloxy group. Also disclosed are an additive-resin admixture, a method of treating a wood product, and a wood product.

  20. Effect of One Percent Chlorhexidine Addition on the Antibacterial Activity and Mechanical Properties of Sealants: An in vitro Study

    PubMed Central

    Asokan, Sharath; John, J Baby; Priya, PR Geetha; Devi, Jagadeesan Gnana

    2015-01-01

    ABSTRACT Aim: The aim of the study was to evaluate the effect of addition of 1% chlorhexidine digluconate solution on the antibacterial activity and mechanical properties of glass ionomer and resin based sealant. Materials and methods: Conventional glass ionomer sealant (GIS) (Fuji VII, Japan) and resin sealant (Clinpro 3M ESPE, USA) were used in this study. Chlorhexidine digluconate (CHX) (20%) liquid was added to both the sealants, and the concentration of chlorhexidine in sealants was adjusted to 1%. The sealants were divided into four groups as: group A (GIS), group B (GIS + 1% CHX), group C (resin sealant), group D (resin sealant + 1% CHX). Five cylindrical specimens were prepared in each group. Their antibacterial activity against Streptococcus mutans and Lactobacillus acidophilus, and their mechanical properties (compressive strength and diametrical tensile strength) were assessed. Mann-Whitney and Wilcoxon signed rank test were used appropriately for statistical analysis (SPSS version 19). Result: Addition of one percent chlorhexidine significantly increased the antibacterial activity of both the sealants. There was a significant difference between groups A and B (p < 0.009), and groups C and D (p < 0.008). There was no significant difference in the mechanical properties of the sealants. Conclusion: Addition of one percent chlorhexidine to the glass ionomer and resin based sealants provided sufficient antibacterial activity, without significantly affecting the mechanical property of the sealants. How to cite this article: Shanmugaavel AK, Asokan S, John JB, Geetha Priya PR, Gnana Devi J. Effect of one percent Chlorhexidine Addition on the Antibacterial Activity and Mechanical Properties of Sealants: An in vitro Study. Int J Clin Pediatr Dent 2015;8(3):196-201. PMID:26628854

  1. A study on the effect of halloysite nanoparticle addition on the strength of glass fiber reinforced plastic

    NASA Astrophysics Data System (ADS)

    Kim, Yun-Hae; Park, Soo-Jeong; Lee, Jin-Woo; Moon, Kyung-Man

    2015-03-01

    Halloysite nanotube, which has been used in the polymer, has been spotlighted as a useful functional materials in the improvement of mechanical properties. In the current study, we established the optimal nanoparticle dispersion and analyzed the mechanical characteristics and the behavior of composites reinforced by HNTs have been synthesized by dispersing HNTs to the unsaturated polyester resin (UPR) and their mechanical characteristics, especially the tensile strength, interlaminar shear strength have been analyzed. Additionally, the reinforcement effect and its variation according to the amount of HNTs was also studied.

  2. Investigations on the influence of composition in the development of Ni-Ti shape memory alloy using laser based additive manufacturing

    NASA Astrophysics Data System (ADS)

    Shiva, S.; Palani, I. A.; Mishra, S. K.; Paul, C. P.; Kukreja, L. M.

    2015-06-01

    Among the various shaped memory alloys (SMA), nitinol (Ni-Ti alloy) finds applications in automotive, aerospace, biomedical and robotics. The conventional route of fabrication of SMA has several limitations, like formation of stable secondary phases, fabrication of simple geometries, etc. This paper reports a novel method of fabricating SMA using a laser based additive manufacturing technique. Three different compositions of Ni and Ti powders (Ni-45% Ti-55%; Ni-50% Ti-50%; Ni-55% Ti45%) were pre-mixed using ball-milling and laser based additive manufacturing system was employed to fabricate circular rings. The material properties of fabricated rings were evaluated using Scanning Electron Microscopy (SEM), Differential scanning calorimeter (DSC), X-ray diffraction (XRD) system and micro-hardness test. All the characterized results showed that SMA could be manufactured using the laser based additive manufacturing process. The properties of laser additive manufactured SMA (Ni-50% Ti-50%) were found to be close to that of conventionally processed SMA.

  3. 1982 Maths Investigation: Technical Report. Mt. Druitt Longitudinal Study.

    ERIC Educational Resources Information Center

    Houghton, Karen; Low, Brian

    Aims of this phase of a longitudinal mathematics achievement investigation were to (1) detect individual and group differences in math achievement among a sample of fourth-year children, (2) monitor changes in math skills since a 1981 math investigation, and (3) identify limits of children's understanding of mathematical concepts. (The math test…

  4. A numerical study of the influence of ammonia addition on the auto-ignition limits of methane/air mixtures.

    PubMed

    Van den Schoor, F; Norman, F; Vandebroek, L; Verplaetsen, F; Berghmans, J

    2009-05-30

    In this study the auto-ignition limit of ammonia/methane/air mixtures is calculated based upon a perfectly stirred reactor model with convective heat transfer. The results of four different reaction mechanisms are compared with existing experimental data at an initial temperature of 723 K with ammonia concentrations of 0-20 mol.% and methane concentrations of 2.5-10 mol.%. It is found that the calculation of the auto-ignition limit pressure at constant temperature leads to larger relative deviations between calculated and experimental results than the calculation of the auto-ignition temperature at constant pressure. In addition to the calculations, a reaction path analysis is performed to explain the observed lowering of the auto-ignition limit of methane/air mixtures by ammonia addition. It is found that this decrease is caused by the formation of NO and NO(2), which enhance the oxidation of methane at low temperatures. PMID:18926632

  5. The influence of deposit control additives on nitrogen oxides emissions from spark ignition engines (case study: Tehran).

    PubMed

    Bidhendi, Gholamreza Nabi; Zand, Ali Daryabeigi; Tabrizi, Alireza Mikaeili; Pezeshk, Hamid; Baghvand, Akbar

    2007-04-15

    In the present research, the influence of a deposit control additive on NOx emissions from two types of gasoline engine vehicles i.e., Peykan (base on Hillman) and Pride (South Korea Kia motors) was studied. Exhaust NOx emissions were measured in to stages, before decarbonization process and after that. Statistical analysis was conducted on the measurement results. Results showed that NOx emissions from Peykans increased 0.28% and NOx emissions from Pride automobiles decreased 6.18% on average, due to the elimination of engine deposits. The observed variations were not statistically and practically significant. The results indicated that making use of detergent additives is not an effective way to reduce the exhaust NOx emissions from gasoline engine vehicles. PMID:19069943

  6. A mechanistic study of the addition of alcohol to a five-membered ring silene via a photochemical reaction.

    PubMed

    Su, Ming-Der

    2016-03-21

    The mechanism for the photochemical rearrangement of a cyclic divinyldisilane (1-Si) in its first excited state ((1)π → (1)π*) is determined using the CAS/6-311G(d) and MP2-CAS/6-311++G(3df,3pd) levels of theory. The photoproduct, a cyclic silene, reacts with various alcohols to yield a mixture of cis- and trans- adducts. The two reaction pathways are denoted as the cis- addition path (path A) and the trans-addition path (path B). These model studies demonstrate that conical intersections play a crucial role in the photo-rearrangements of cyclic divinyldisilanes. The theoretical evidence also demonstrates that the addition of alcohol to a cyclic divinyldisilane follows the reaction path: cyclic divinyldisilane → Franck-Condon region → conical intersection → photoproduct (cyclic silene) → local intermediate (with alcohol) → transition state → cis- or trans-adduct. The theoretical studies demonstrate that the steric effects as well as the concentrations of CH3OH must have a dominant role in determining the yields of the final adducts by stereochemistry. The same mechanism for the carbon derivative (1-C) is also considered in this work. However, the theoretical results indicate that 1-C does not undergo a methanol addition reaction via the photochemical reaction pathway, since its energy of conical intersection (S1/S0-CI-C) is more than that of its FC (FC-C). The reason for these phenomena could be that the atomic radius of carbon is much smaller than that of silicon (77 and 117 pm, respectively). As a result, the conformation for 1-C is more sterically congested than that for 1-Si, along the 1,3-silyl-migration pathway. PMID:26928893

  7. Scoping Study Investigating PWR Instrumentation during a Severe Accident Scenario

    SciTech Connect

    Rempe, J. L.; Knudson, D. L.; Lutz, R. J.

    2015-09-01

    significantly exceeded QE limits for extended time periods for the low frequency STSBO sequence evaluated in this study. It is recognized that the core damage frequency (CDF) of the sequence evaluated in this scoping effort would be considerably lower if evaluations considered new FLEX equipment being installed by industry. Nevertheless, because of uncertainties in instrumentation response when exposed to conditions beyond QE limits and alternate challenges associated with different sequences that may impact sensor performance, it is recommended that additional evaluations of instrumentation performance be completed to provide confidence that operators have access to accurate, relevant, and timely information on the status of reactor systems for a broad range of challenges associated with risk important severe accident sequences.

  8. Guest investigator program study: Physics of equatorial plasma bubbles

    NASA Technical Reports Server (NTRS)

    Tsunoda, Roland T.

    1994-01-01

    -shaped plasma bubbles. The second topic was pursued because the inability to predict the day-to-day occurrence of plasma bubbles indicated inadequate knowledge of the physics of plasma bubbles. An understanding of bubble formation requires an understanding of the roles of the various terms in the linearized growth rate of the collisional Rayleigh-Taylor instability. In our study, we examined electric-field perturbations found in SM-D EFI data and found that the seeding is more likely to be produced in the E region rather than the F region. The results of this investigation are presented in the Appendix of this report and will be submitted for publication in the Journal of Geophysical Research.

  9. Usefulness of comprehensive feasibility studies in environmental epidemiology investigations: a case study in Minnesota.

    PubMed Central

    Bender, A P; Williams, A N; Sprafka, J M; Mandel, J S; Straub, C P

    1988-01-01

    Episodes of public water supply contamination with industrial or agricultural chemicals frequently give rise to public concerns about adverse health effects. These concerns may precipitate epidemiologic or clinical investigations requiring large expenditures of state and federal resources regardless of whether such investigations are justified by scientific criteria. An alternative is a comprehensive feasibility study, utilizing all available information to determine whether large-scale studies are warranted or feasible. At a relatively modest cost, a feasibility study allows health officials to identify information needs and deficiencies, outline potential study options and costs, clearly establish the rationale for a proposed study or, conversely, prevent unwarranted expenditures of public resources. Furthermore, a feasibility study may in itself resolve many community and scientific concerns. This article provides a case study of the usefulness of a formal feasibility study in a situation involving an elevated cancer rate and contaminated municipal water supply wells surrounding a federal superfund site. PMID:3341499

  10. An additional study of multi-muon events produced in $p\\bar{p}$ collisions at $\\sqrt{s}=1.96$ TeV

    SciTech Connect

    Aaltonen, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Apollinari, G.; Apresyan, A.; Arisawa, T.; Artikov, A.; /Dubna, JINR /Fermilab

    2011-11-01

    We present one additional study of multi-muon events produced at the Fermilab Tevatron collider and recorded by the CDF II detector. We use a data set acquired with a dedicated dimuon trigger and corresponding to an integrated luminosity of 3.9 fb{sup -1}. We investigate the distribution of the azimuthal angle between the two trigger muons in events containing at least four additional muon candidates to test the compatibility of these events with originating from known QCD processes. We find that this distribution is markedly different from what is expected from such QCD processes and this observation strongly disfavours the possibility that multi-muon events result from an underestimate of the rate of misidentified muons in ordinary QCD events.

  11. Experimental investigation of solid by-product as sensible heat storage material: Characterization and corrosion study

    NASA Astrophysics Data System (ADS)

    Ortega-Fernández, Iñigo; Faik, Abdessamad; Mani, Karthik; Rodriguez-Aseguinolaza, Javier; D'Aguanno, Bruno

    2016-05-01

    The experimental investigation of water cooled electrical arc furnace (EAF) slag used as filler material in the storage tank for sensible heat storage application was demonstrated in this study. The physicochemical and thermal properties of the tested slags were characterized by using X-ray diffraction, scanning electron microcopy, Fourier transform infrared spectroscopy, Raman spectroscopy and laser flash analysis, respectively. In addition, the chemical compatibility between slags and molten nitrate salt (60 wt. % NaNO3 and 40 wt. % KNO3) was investigated at 565 °C for 500 hrs. The obtained results were clearly demonstrated that the slags showed a good corrosion resistance in direct contact with molten salt at elevated temperature. The present study was clearly indicated that a low-cost filler material used in the storage tank can significantly reduce the overall required quantities of the relatively higher cost molten salt and consequently reduce the overall cost of the electricity production.

  12. Numerical study on the influence of hydrogen addition on soot formation in a laminar ethylene-air diffusion flame

    SciTech Connect

    Guo, Hongsheng; Liu, Fengshan; Smallwood, Gregory J.; Guelder, OEmer L.

    2006-04-15

    The influence of hydrogen addition to the fuel of an atmosphere pressure coflow laminar ethylene-air diffusion flame on soot formation was studied by numerical simulation. A detailed gas-phase reaction mechanism, which includes aromatic chemistry up to four rings, and complex thermal and transport properties were used. The fully coupled elliptic governing equations were solved. The interactions between soot and gas-phase chemistry were taken into account. Radiation heat transfer from CO{sub 2}, CO, H{sub 2}O, and soot was calculated using the discrete-ordinates method coupled to a statistical narrow-band-correlated K-based wide-band model. The predicted results were compared with the available experimental data and analyzed. It is indicated that the addition of hydrogen to the fuel in an ethylene-air diffusion flame suppresses soot formation through the effects of dilution and chemistry. This result is in agreement with available experiments. The simulations further suggest that the chemically inhibiting effect of hydrogen addition on soot formation is due to the decrease of hydrogen atom concentration in soot surface growth regions and higher concentration of molecular hydrogen in the lower flame region. (author)

  13. Three new double-headed nucleotides with additional nucleobases connected to C-5 of pyrimidines; synthesis, duplex and triplex studies.

    PubMed

    Kumar, Pawan; Sharma, Pawan K; Hansen, Jonas; Jedinak, Lukas; Reslow-Jacobsen, Charlotte; Hornum, Mick; Nielsen, Poul

    2016-02-15

    In the search for double-coding DNA-systems, three new pyrimidine nucleosides, each coded with an additional nucleobase anchored to the major groove face, are synthesized. Two of these building blocks carry a thymine at the 5-position of 2'-deoxyuridine through a methylene linker and a triazolomethylene linker, respectively. The third building block carries an adenine at the 6-position of pyrrolo-2'-deoxycytidine through a methylene linker. These double-headed nucleosides are introduced into oligonucleotides and their effects on the thermal stabilities of duplexes are studied. All studied double-headed nucleotide monomers reduce the thermal stability of the modified duplexes, which is partially compensated by using consecutive incorporations of the modified monomers or by flanking the new double-headed analogs with members of our former series containing propyne linkers. Also their potential in triplex-forming oligonucleotides is studied for two of the new double-headed nucleotides as well as the series of analogs with propyne linkers. The most stable triplexes are obtained with single incorporations of additional pyrimidine nucleobases connected via the propyne linker. PMID:26778611

  14. Investigating the Use of Coherence Analysis on Mandibular Electromyograms to Investigate Neural Control of Early Oromandibular Behaviours: A Pilot Study

    ERIC Educational Resources Information Center

    Steeve, Roger W.; Price, Christiana M.

    2010-01-01

    An empirical method for investigating differences in neural control of jaw movement across oromandibular behaviours is to compute the coherence function for electromyographic signals obtained from mandibular muscle groups. This procedure has been used with adults but not extended to children. This pilot study investigated if coherence analysis…

  15. Investigation of Students' Epistemological Beliefs and Attitudes towards Studying

    ERIC Educational Resources Information Center

    Onen, Aysem Seda

    2011-01-01

    This study consists of the analysis on the relationship between the epistemological beliefs of secondary level students and their attitudes towards studying. The sampling of the study was formed by 440 students studying at Grade 10, 11 and 12 in secondary schools. The Epistemological Belief Questionnaire and the Attitudes towards Studying Scale,…

  16. Addition of low concentrations of an ionic liquid to a base oil reduces friction over multiple length scales: a combined nano- and macrotribology investigation.

    PubMed

    Li, Hua; Somers, Anthony E; Howlett, Patrick C; Rutland, Mark W; Forsyth, Maria; Atkin, Rob

    2016-03-01

    The efficacy of ionic liquids (ILs) as lubricant additives to a model base oil has been probed at the nanoscale and macroscale as a function of IL concentration using the same materials. Silica surfaces lubricated with mixtures of the IL trihexyl(tetradecyl)phosphonium bis(2,4,4-trimethylpentyl)phosphinate and hexadecane are probed using atomic force microscopy (AFM) (nanoscale) and ball-on-disc tribometer (macroscale). At both length scales the pure IL is a much more effective lubricant than hexadecane. At the nanoscale, 2.0 mol% IL (and above) in hexadecane lubricates the silica as well as the pure IL due to the formation of a robust IL boundary layer that separates the sliding surfaces. At the macroscale the lubrication is highly load dependent; at low loads all the mixtures lubricate as effectively as the pure IL, whereas at higher loads rather high concentrations are required to provide IL like lubrication. Wear is also pronounced at high loads, for all cases except the pure IL, and a tribofilm is formed. Together, the nano- and macroscales results reveal that the IL is an effective lubricant additive - it reduces friction - in both the boundary regime at the nanoscale and mixed regime at the macroscale. PMID:26865399

  17. Experimental and computational mechanistic investigation of chlorocarbene additions to bridgehead carbene-anti-Bredt systems: noradamantylcarbene-adamantene and adamantylcarbene-homoadamantene.

    PubMed

    Hare, Stephanie R; Orman, Marina; Dewan, Faizunnahar; Dalchand, Elizabeth; Buzard, Camilla; Ahmed, Sadia; Tolentino, Julia C; Sethi, Ulweena; Terlizzi, Kelly; Houferak, Camille; Stein, Aliza M; Stedronsky, Alexandra; Thamattoor, Dasan M; Tantillo, Dean J; Merrer, Dina C

    2015-05-15

    Cophotolysis of noradamantyldiazirine with the phenanthride precursor of dichlorocarbene or phenylchlorodiazirine in pentane at room temperature produces noradamantylethylenes in 11% yield with slight diastereoselectivity. Cophotolysis of adamantyldiazirine with phenylchlorodiazirine in pentane at room temperature generates adamantylethylenes in 6% yield with no diastereoselectivity. (1)H NMR showed the reaction of noradamantyldiazirine + phenylchlorodiazirine to be independent of solvent, and the rate of noradamantyldiazirine consumption correlated with the rate of ethylene formation. Laser flash photolysis showed that reaction of phenylchlorocarbene + adamantene was independent of adamantene concentration. The reaction of phenylchlorocarbene + homoadamantene produces the ethylene products with k = 9.6 × 10(5) M(-1) s(-1). Calculations at the UB3LYP/6-31+G(d,p) and UM062X/6-31+G(d,p)//UB3LYP/6-31+G(d,p) levels show the formation of exocyclic ethylenes to proceed (a) on the singlet surface via stepwise addition of phenylchlorocarbene (PhCCl) to bridgehead alkenes adamantene and homoadamantene, respectively, producing an intermediate singlet diradical in each case, or (b) via addition of PhCCl to the diazo analogues of noradamantyl- and adamantyldiazirine. Preliminary direct dynamics calculations on adamantene + PhCCl show a high degree of recrossing (68%), indicative of a flat transition state surface. Overall, 9% of the total trajectories formed noradamantylethylene product, each proceeding via the computed singlet diradical. PMID:25902301

  18. Can additional urban development have major impacts on streamflow of a peri-urban catchment? A case study from Portugal

    NASA Astrophysics Data System (ADS)

    Ferreira, Carla; Walsh, Rory; Nunes, João; Steenhuis, Tammo; de Lima, João; Coelho, Celeste; Ferreira, António

    2016-04-01

    It is well known that urban development brings about changes in hydrological response. Relatively little, however, is known about impacts on streamflow during urban development in the Mediterranean climate. This paper examines changes in streamflow resulting from the construction of an enterprise park, a major road and apartment blocks in a small partially urbanized peri-urban catchment (6.2 km2) in central Portugal. These developments led to an increase in urban area from 32% to 40% over a five-year period (hydrological years 2008/09-2012/13). In the initial two-year period minor land-use changes increased impervious surfaces from 12.8% to 13.2%. The subsequent three-year period led to a further 17.2% increase in impervious area. Streamflow was recorded by a V-notch weir at the catchment outlet. Rainfall was recorded at a weather station 0.5km north of the catchment, and by five tipping-bucket raingauges installed in January 2011 within the study catchment. Annual runoff and storm runoff coefficients ranged from 14% to 21% and 9% to 14%, respectively, recorded in 2011/12 and 2012/13. Although these differences in runoff were caused in part by variation in rainfall, the comparison between 2009/10 (pre-) and 2012/13 (post-additional urban development), with broadly similar rainfall (887mm vs 947mm, respectively) and evapotranspiration (740mm vs 746mm), showed a 43% increase in storm runoff (from 90mm to 129mm), resulting from additional overland flow generated largely by the 4.4% increase in impervious surfaces. The additional urban development also led to changes in hydrograph parameters. The increase in storm runoff was not progressive over the study period, but regression lines of storm runoff against rainstorm parameters exhibited higher vertical positions in 2012/13 than 2008/09. Increasing peak flows, however, were more progressive over the study period, with annual regression lines displaying higher vertical positions, but with a clear distance between pre

  19. A DFT study of addition reaction between fragment ion (CH₂) units and fullerene (C₆₀) molecule.

    PubMed

    Zaragoza, Irineo Pedro; Vergara, Jaime; Pérez-Manríquez, Liliana; Salcedo, Roberto

    2011-05-01

    The theoretical study of the interaction between CH(2) and fullerene (C(60)) suggests the existence of an addition reaction mechanism; this feature is studied by applying an analysis of electronic properties. Several different effects are evident in this interaction as a consequence of the particular electronic transfer which occurs during the procedure. The addition or insertion of the methylene group results in a process, where the inclusion of CH(2) into a fullerene bond produces the formation of several geometric deformations. A simulation of these procedures was carried out, taking advantage of the dynamic semi-classical Born-Oppenheimer approximation. Dynamic aspects were analyzed at different speeds, for the interaction between the CH(2) group and the two bonds: CC (6, 6) and CC (6, 5) respectively on the fullerene (C(60)) rings. All calculations which involved electrons employed DFT as well as exchange and functional correlation. The results indicate a tendency for the CH(2) fragment to attack the CC (6, 5) bond. PMID:20658255

  20. Experimental study on the characteristics of ventilated cavitation around an underwater navigating body influenced by turbulent drag-reducing additives

    NASA Astrophysics Data System (ADS)

    Jiang, ChenXing; Li, FengChen

    2015-09-01

    In this study, a new control strategy for turbulent drag reduction involving ventilated cavitation is proposed. The configurational and hydrodynamic characteristics of ventilated cavities influenced by turbulent drag-reducing additives were experimentally studied in water tunnel. The test model was fixed in the water tunnel by a strut in the aft-part. Aqueous solutions of CTAC/NaSal (cetyltrimethyl ammonium chloride/sodium salicylate) with weight concentrations of 100, 200, 400 and 600 ppm (part per million), respectively, were injected into the ventilated air cavity from the edge of the cavitator with accurate control by an injection pump. The cavity configurations were recorded by a high-speed CCD camera. The hydrodynamic characteristics of the test model were measured by a six-component balance. Experimental results show that, within the presently tested cases, the lengths of cavity influenced by drag-reducing solution are smaller than normal condition (ventilated cavity) in water, but the asymmetry of the cavity is improved. The drag resisted by the test model is reduced dramatically (the maximum drag reduction can reach to 80%) and the re-entrant jet is more complex after the CTAC solution is injected into the cavity. Turbulent drag-reducing additives have the potential in enhancement of supercavitating asymmetry and further drag reduction.

  1. An Exploratory Investigation of Study-Abroad Online Information Cues

    ERIC Educational Resources Information Center

    Teng, Shasha; Khong, Kok Wei

    2015-01-01

    Despite numerous studies on the factors involved in the decision-making process on study abroad, little attention has been paid to the initial stage when students process information. This qualitative study aims to map out the cues involved when Chinese students process study-abroad information from an information-processing perspective. Findings…

  2. Process Based Investigations of Conceptual Development: An Explorative Study

    ERIC Educational Resources Information Center

    von Aufschnaiter, Claudia

    2006-01-01

    Research on conceptual change is still a powerful framework for empirical investigations on students' learning of science. During recent years, an increasing body of research has explored students' concepts prior and subsequent to instruction, leading to an extensive documentation of students' concepts including the difficulties and opportunities…

  3. Additive influence of genetic predisposition and conventional risk factors in the incidence of coronary heart disease: a population-based study in Greece

    PubMed Central

    Yiannakouris, Nikos; Katsoulis, Michail; Trichopoulou, Antonia; Ordovas, Jose M; Trichopoulos, Dimitrios

    2014-01-01

    Objectives An additive genetic risk score (GRS) for coronary heart disease (CHD) has previously been associated with incident CHD in the population-based Greek European Prospective Investigation into Cancer and nutrition (EPIC) cohort. In this study, we explore GRS-‘environment’ joint actions on CHD for several conventional cardiovascular risk factors (ConvRFs), including smoking, hypertension, type-2 diabetes mellitus (T2DM), body mass index (BMI), physical activity and adherence to the Mediterranean diet. Design A case–control study. Setting The general Greek population of the EPIC study. Participants and outcome measures 477 patients with medically confirmed incident CHD and 1271 controls participated in this study. We estimated the ORs for CHD by dividing participants at higher or lower GRS and, alternatively, at higher or lower ConvRF, and calculated the relative excess risk due to interaction (RERI) as a measure of deviation from additivity. Results The joint presence of higher GRS and higher risk ConvRF was in all instances associated with an increased risk of CHD, compared with the joint presence of lower GRS and lower risk ConvRF. The OR (95% CI) was 1.7 (1.2 to 2.4) for smoking, 2.7 (1.9 to 3.8) for hypertension, 4.1 (2.8 to 6.1) for T2DM, 1.9 (1.4 to 2.5) for lower physical activity, 2.0 (1.3 to 3.2) for high BMI and 1.5 (1.1 to 2.1) for poor adherence to the Mediterranean diet. In all instances, RERI values were fairly small and not statistically significant, suggesting that the GRS and the ConvRFs do not have effects beyond additivity. Conclusions Genetic predisposition to CHD, operationalised through a multilocus GRS, and ConvRFs have essentially additive effects on CHD risk. PMID:24500614

  4. [Study on the spectra of Au/CeO2 catalysts modified by La2O3 additive].

    PubMed

    Zhang, Qing; He, Zhen-Liang; Li, Jin-Wei; Zhan, Ying-Ying; Lin, Xing-Yi; Zheng, Qi

    2008-04-01

    For Au-ceria catalysts prepared by deposition-precipitation method, the catalytic performance of water gas shift reaction was studied with different La loadings. In the complete doping range, ceria retains with its cubic fluorite structures. XRD, HRTEM and UV-Vis-DRS, studies showed that La doping can improve the activity of Au-ceria catalyst by stabilizing ceria and modifying its morphology. In addition, the test of catalyst stability evaluation also proved, that a better stability performance of Au-ceria catalyst can be realized by appropriate La doping. The Au/CL5.0 sample with 5 at % La doping showed the best performance in WGS reaction. PMID:18619331

  5. Feasibility Study on 3-D Printing of Metallic Structural Materials with Robotized Laser-Based Metal Additive Manufacturing

    NASA Astrophysics Data System (ADS)

    Ding, Yaoyu; Kovacevic, Radovan

    2016-05-01

    Metallic structural materials continue to open new avenues in achieving exotic mechanical properties that are naturally unavailable. They hold great potential in developing novel products in diverse industries such as the automotive, aerospace, biomedical, oil and gas, and defense. Currently, the use of metallic structural materials in industry is still limited because of difficulties in their manufacturing. This article studied the feasibility of printing metallic structural materials with robotized laser-based metal additive manufacturing (RLMAM). In this study, two metallic structural materials characterized by an enlarged positive Poisson's ratio and a negative Poisson's ratio were designed and simulated, respectively. An RLMAM system developed at the Research Center for Advanced Manufacturing of Southern Methodist University was used to print them. The results of the tensile tests indicated that the printed samples successfully achieved the corresponding mechanical properties.

  6. Feasibility Study on 3-D Printing of Metallic Structural Materials with Robotized Laser-Based Metal Additive Manufacturing

    NASA Astrophysics Data System (ADS)

    Ding, Yaoyu; Kovacevic, Radovan

    2016-07-01

    Metallic structural materials continue to open new avenues in achieving exotic mechanical properties that are naturally unavailable. They hold great potential in developing novel products in diverse industries such as the automotive, aerospace, biomedical, oil and gas, and defense. Currently, the use of metallic structural materials in industry is still limited because of difficulties in their manufacturing. This article studied the feasibility of printing metallic structural materials with robotized laser-based metal additive manufacturing (RLMAM). In this study, two metallic structural materials characterized by an enlarged positive Poisson's ratio and a negative Poisson's ratio were designed and simulated, respectively. An RLMAM system developed at the Research Center for Advanced Manufacturing of Southern Methodist University was used to print them. The results of the tensile tests indicated that the printed samples successfully achieved the corresponding mechanical properties.

  7. BASF studies: epidemiological and clinical investigations on dioxin-exposed chemical workers.

    PubMed

    Zober, A; Messerer, P; Ott, M G

    First in 1953 and again later in 1988, BASF Aktiengesellschaft, Ludwigshafen, Germany, faced production-related dioxin contamination problems. In both situations, the immediate actions were efforts to limit the potential for employee exposure. In 1953, after a reactor accident, the production of trichlorophenol was stopped and extensive clean-up and demolition work was undertaken. In 1988, major technical improvements were made to an extrusion blending process and the flame retardants were changed to substances that chemically should not be dioxin precursors. The health experience of the potentially exposed populations has been followed extensively in both situations. Five recent epidemiological investigations: a long-term mortality follow-up, a morbidity study, a clinical laboratory study, and a chromosome study of persons from the 1953 accident cohort, as well as immunological studies of employees assigned to the extrusion operations, are discussed. In addition, considerable dioxin biomonitoring data from blood lipids for both populations are summarized. PMID:9508734

  8. Hazard and risk assessment of a nanoparticulate cerium oxide-based diesel fuel additive - a case study.

    PubMed

    Park, Barry; Donaldson, Kenneth; Duffin, Rodger; Tran, Lang; Kelly, Frank; Mudway, Ian; Morin, Jean-Paul; Guest, Robert; Jenkinson, Peter; Samaras, Zissis; Giannouli, Myrsini; Kouridis, Haris; Martin, Patricia

    2008-04-01

    Envirox is a scientifically and commercially proven diesel fuel combustion catalyst based on nanoparticulate cerium oxide and has been demonstrated to reduce fuel consumption, greenhouse gas emissions (CO(2)), and particulate emissions when added to diesel at levels of 5 mg/L. Studies have confirmed the adverse effects of particulates on respiratory and cardiac health, and while the use of Envirox contributes to a reduction in the particulate content in the air, it is necessary to demonstrate that the addition of Envirox does not alter the intrinsic toxicity of particles emitted in the exhaust. The purpose of this study was to evaluate the safety in use of Envirox by addressing the classical risk paradigm. Hazard assessment has been addressed by examining a range of in vitro cell and cell-free endpoints to assess the toxicity of cerium oxide nanoparticles as well as particulates emitted from engines using Envirox. Exposure assessment has taken data from modeling studies and from airborne monitoring sites in London and Newcastle adjacent to routes where vehicles using Envirox passed. Data have demonstrated that for the exposure levels measured, the estimated internal dose for a referential human in a chronic exposure situation is much lower than the no-observed-effect level (NOEL) in the in vitro toxicity studies. Exposure to nano-size cerium oxide as a result of the addition of Envirox to diesel fuel at the current levels of exposure in ambient air is therefore unlikely to lead to pulmonary oxidative stress and inflammation, which are the precursors for respiratory and cardiac health problems. PMID:18444008

  9. Modeling and investigative studies of Jovian low frequency emissions

    NASA Astrophysics Data System (ADS)

    Menietti, J. D.; Green, J. L.; Six, N. F.; Gulkis, S.

    1986-09-01

    The Voyager data in a newly produced noise-reduced and recalibrated format has been received. New color spectrograms were developed on high resolution color terminals which display this data. The production of these new spectrograms utilizing the new format data is quite important, because it eliminates a serious problem of noise contamination and miscalibration in the old data set. In addition, a new Jovian plasma model was introduced, which includes the Io torus and accounts for 7 ionic species. The new plasma model is important in the ray tracing of hectometric (HOM) and kilometric (KOM) radiation which may be influenced by the Io torus.

  10. Methyl iodide oxidative addition to [Rh(acac)(CO)(PPh3)]: an experimental and theoretical study of the stereochemistry of the products and the reaction mechanism.

    PubMed

    Conradie, Marrigje M; Conradie, Jeanet

    2011-08-28

    Density functional theory was used to investigate the oxidative addition and subsequent carbonyl insertion and deinsertion steps of the reaction of methyl iodide to a rhodium(I) acetylacetonato complex of the formula [Rh(acac)(CO)(PPh(3))] (Hacac = acetylacetone). This process has been studied experimentally for many rhodium β-diketonato complexes, but, to the best of our knowledge, this is the first systematic computational study of the complete reaction sequence. Experimental (1)H techniques complement the theoretical results on the stereochemistry of the reaction intermediates and products. (1)H NMR also revealed the existence of a second rhodium(III)-acyl product, which has not been previously observed in this reaction. The calculated Gibbs free energy of activation of the oxidative addition reaction is 71 kJ mol(-1), which is in agreement with the experimental value of 82(1) kJ mol(-1). The DFT-calculated oxidative addition corresponds to an associative S(N)2 nucleophilic attack by the rhodium metal centre on the methyl iodide, which is in agreement with calculated and experimental (in brackets) activation parameters of the reaction, 27 (38.8) kJ mol(-1) for ΔH((≠)) and -147 (-146) J K(-1) mol(-1) for ΔS((≠)). PMID:21761056

  11. Investigation into the effects of vermiculite on NOx reduction and additives on sooting and exhaust infrared signature from a gas-turbine combustor. Master's thesis

    SciTech Connect

    Engel, K.R.

    1990-09-01

    An experimental investigation was conducted to determine the feasibility of using catalytic reduction of NOX emissions from a typical jet engine combustor in the test cell environment. A modified T-63 combustor in combination with an instrumented 21 foot augmentation tube containing a vermiculite catalyst was used. Several methods for containing the vermiculite were attempted. Both vermiculite and vermiculite which had been coated with thiourea were used. Up to 19% reduction in NOX concentrations was obtained using the vermiculite coated with thiourea, however the pressure loss across the catalyst bed was measured to be 36 in. H2O. The techniques used proved ineffective and unacceptable for gas turbine engine test cell applications. Tests were conducted using both Wynn's 15/590 and Catane TM (ferrocene) fuel supplements in order to determine their effectiveness for soot reduction and whether or not the exhaust plume could be changed.

  12. [Study on chromosomes aberration in wheat-rye disomics addition lines induced by the gametocidal chromosome 2C].

    PubMed

    Sun, Zhong-Ping; Wang, Zhan-Bin; Xu, Xiang-Ling; Li, Ji-Lin

    2004-11-01

    In the present study,Chinese Spring-Imperial (1 R-7R) wheat-rye disomic addition lines were hybridized with Chinese Spring-2C (derived from Aegilops cylindrica) disomic addition lines. The F1 hybrids were examined by mitotic and meiotic analysis. There were observed abnormal chromosome configurations. A total of 430 F2 plants were obtained by self-pollination. Chromosomes aberrations, such as translocation, deletions, isobrachial and dicentromere chromosomes, are identified in F2 individual plants by C-banding combined with fluorescent in situ hybridization (FISH). Additionally, chromosome spontaneous substitutions such as 2C substituting for wheat chromosomes 2A, 2B and 2D were also observed. The rule and frequency of chromosome aberration in F2 are the following: 22 out of 430 F2 plants (5.11%) were found involving aberration rye chromosomes. Among them, 10 plants were identified as wheat-rye chromosome translocation lines comprising 2.3%. Rye chromosome deletions comprised 12 of them (2.79%). 3 isobrachial aberrations were detected (about 0.7%), too. Most of the translocation lines are with wheat centromere, only one of them is with rye centromere. Rye chromosome aberrations occurred unevenly among homoeologous groups. There were 5 in 1R, 3 in 2R, 1 in 3R, 3 in 4R, 6 in 5R and 4 in 6R. The majority of the translocation lines are terminal translocation. 54 out of the total 430 progenies are wheat deletions,and 27 are distributed in the A group, 20 in the B group and 7 in the D group respectively. Finally,we discussed the possible cause for the uneven chromosome aberration among homoeologous groups in wheat and rye as well as the effect characteristics of 2C on wheat and rye chromosome. PMID:15651680

  13. The investigation of supply chain's reliability measure: a case study

    NASA Astrophysics Data System (ADS)

    Taghizadeh, Houshang; Hafezi, Ehsan

    2012-10-01

    In this paper, using supply chain operational reference, the reliability evaluation of available relationships in supply chain is investigated. For this purpose, in the first step, the chain under investigation is divided into several stages including first and second suppliers, initial and final customers, and the producing company. Based on the formed relationships between these stages, the supply chain system is then broken down into different subsystem parts. The formed relationships between the stages are based on the transportation of the orders between stages. Paying attention to the system elements' location, which can be in one of the five forms of series namely parallel, series/parallel, parallel/series, or their combinations, we determine the structure of relationships in the divided subsystems. According to reliability evaluation scales on the three levels of supply chain, the reliability of each chain is then calculated. Finally, using the formulas of calculating the reliability in combined systems, the reliability of each system and ultimately the whole system is investigated.

  14. Economic impact of stimulated technological activity. Part 3: Case study, knowledge additions and earth links from space crew systems

    NASA Technical Reports Server (NTRS)

    1971-01-01

    A case study of knowledge contributions from the crew life support aspect of the manned space program is reported. The new information needed to be learned, the solutions developed, and the relation of new knowledge gained to earthly problems were investigated. Illustrations are given in the following categories: supplying atmosphere for spacecraft; providing carbon dioxide removal and recycling; providing contaminant control and removal; maintaining the body's thermal balance; protecting against the space hazards of decompression, radiation, and meteorites; minimizing fire and blast hazards; providing adequate light and conditions for adequate visual performance; providing mobility and work physiology; and providing adequate habitability.

  15. Remedial investigation/feasibility study for the David Witherspoon, Inc., 901 Site, Knoxville, Tennessee: Volume 1

    SciTech Connect

    1996-10-01

    This remedial investigation (RI)/feasibility study (FS) supports the selection of remedial actions for the David Witherspoon, Inc. 901 Maryville Pike Site in Knoxville, Tennessee. Operations at the site, used as a recycling center, have resulted in past, present, and potential future releases of hazardous substances in to the environment. This Site is a Tennessee Superfund site. A phased approach was planned to (1) gather existing data from previous investigations managed by the Tenn. Dept. of Environment and Conservation; (2) perform a preliminary RI, including risk assessments, and an FS with existing data to identify areas where remedial action may be necessary; (3) gather additional field data to adequately define the nature and extent of risk-based contaminants that present identifiable threats to human and/or ecological receptors; and (4) develop remedial action alternatives to reduce risks to acceptable levels.

  16. A Thrust and Impulse Study of Guanidinium Azo-Tetrazolate as an Additive for Hybrid Rocket Fuel

    NASA Astrophysics Data System (ADS)

    Patton, J.; Wright, A. M.; Dunn, L.; Alford, B.

    2000-03-01

    A thrust and impulse study of the hybrid rocket fuel additive Guanidinium Azo-Tetrazolate (GAT) was conducted at the University of Arkansas at Little Rock (UALR) Hybrid Rocket Facility. GAT is an organic salt with a high percentage of nitrogen. GAT was mixed with the standard hybrid rocket fuel, Hydroxyl-Terminated Polybutadiene (HTPB), in the concentration of 15%, by mass. The fuel grains with the GAT additive were fired for 4 second runs with the oxygen flows of 0.05, 0.07, 0.09, and 0.12 lbm/sec. For each run average thrust, total impulse, and specific impulse were measured. Average thrust, specific impulse, and total impulse vs. oxygen flow were plotted. Similar data was collected for plain HTPB/PAPI fuels for comparison. GAT was found to increase the thrust output when it was added to the standard hybrid rocket fuel, HTPB. GAT also increased the total impulse during the run. The thrust and total impulse were increased at all flows, but especially at the lower oxygen flow rates. Specific impulse only increased during the lower oxygen flow runs, and decreased slightly for the higher oxygen flow runs.

  17. Influence of CuO and ZnO addition on the multicomponent phosphate glasses: Spectroscopic studies

    NASA Astrophysics Data System (ADS)

    Szumera, Magdalena; Wacławska, Irena; Sułowska, Justyna

    2016-06-01

    The spectra of phosphate-silicate glasses from the P2O5-SiO2-K2O-MgO-CaO system modified with the addition of CuO or ZnO have been studied by means of FTIR, Raman and 31P MAS NMR spectroscopy. All glasses were synthesized by the conventional melt-quenching technique and their homogeneous chemical composition was controlled and confirmed. By using the aforementioned research techniques, the presence of structural units with various degrees of polymerization was shown in the structure of analyzed phosphate-silicate glasses: Q3, Q2, Q1 and Q0. It was found that an increase in the content of CuO or ZnO in the composition of analyzed glasses, which are introduced at the expense of decreasing amounts of CaO and MgO, has a different influence on the phospho-oxygen network. It was shown that copper ions cause its gradual polymerization, while zinc ions cause its depolymerization. At the same time, polymerization of the silico-oxygen subnetwork was found. Additionally, in the case of glasses containing increasing amounts of ZnO, a change of the role of zinc ions in the vitreous matrix was confirmed (from the modifier to a structure-forming component).

  18. Modeling and investigative studies of Jovian low frequency emissions

    NASA Technical Reports Server (NTRS)

    Menietti, J. D.; Green, James L.; Six, N. Frank; Gulkis, S.

    1986-01-01

    Jovian decametric (DAM) and hectometric (HOM) emissions were first observed over the entire spectrum by the Voyager 1 and 2 flybys of the planet. They display unusual arc-like structures on frequency-versus-time spectrograms. Software for the modeling of the Jovian plasma and magnetic field environment was performed. In addition, an extensive library of programs was developed for the retrieval of Voyager Planetary Radio Astronomy (PRA) data in both the high and low frequency bands from new noise-free, recalibrated data tapes. This software allows the option of retrieving data sorted with respect to particular sub-Io longitudes. This has proven to be invaluable in the analyses of the data. Graphics routines were also developed to display the data on color spectrograms.

  19. Policy Forum: Studying Eyewitness Investigations in the Field

    PubMed Central

    Dawes, Robyn; Jacoby, Larry L.; Kahneman, Daniel; Lempert, Richard; Roediger, Henry L.; Rosenthal, Robert

    2007-01-01

    This article considers methodological issues arising from recent efforts to provide field tests of eyewitness identification procedures. We focus in particular on a field study (Mecklenburg 2006) that examined the “double blind, sequential” technique, and consider the implications of an acknowledged methodological confound in the study. We explain why the confound has severe consequences for assessing the real-world implications of this study. PMID:17610149

  20. Impact of Pt additives on the surface reactions between SnO2, water vapour, CO and H2; an operando investigation.

    PubMed

    Großmann, Katharina; Wicker, Susanne; Weimar, Udo; Barsan, Nicolae

    2013-11-28

    The impact of Pt doping on the surface reactions between tin dioxide, water vapour, CO and H2 was investigated by a combination of simultaneously performed operando DRIFT (Diffuse Reflectance Infrared Fourier Transform) spectroscopy, DC resistance measurements and analysis of the reaction products by using a MS (Mass Spectrometer). Both undoped and Pt doped tin dioxide sensors were exposed to different test gases in synthetic air or in N2 backgrounds. The approach made it possible to identify the differences between the two materials with respect to their surface chemistry and their impact on the gas sensing performance. The main finding is that the presence of Pt changes the reaction partners' nature for water vapour and H2 on the one hand, and CO on the other hand when the sensors are operated in air. In this way the cross interference effect of humidity, which is responsible for the loss of CO sensing performance for the sensors based on undoped SnO2, is reversed. PMID:24105035

  1. An investigation of composite electrolytes by mixing polyethylene oxide- and polytetramethylene glycol-based waterborne polyurethane with the addition of LiClO{sub 4}/propylene carbonate

    SciTech Connect

    Wen, T.C.; Chang, J.S.; Cheng, T.T.

    1998-10-01

    Various composite electrolytes (CE) were prepared by mixing polytetramethylene glycol-based waterborne polyurethane [WPU(PTMG)], polyethylene oxide (PEO), and LiClO{sub 4}/propylene carbonate (PC). The conductivity of these CEs was investigated using ac impedance. Differential scanning calorimetry (DSC) and polarizing microscopy (PM) were employed for material characterization. The temperature dependence of the conductivity follows the Arrhenius law for samples with a LiClO{sub 4}/PC content larger than 30%, while for samples with LiClO{sub 4}/PC content approximating 8%, it shows linear segments separated by a transition zone between 25 and 65 C. According to the ac and DSC results, the conductivity is increased, and the melting temperature is decreased by increasing the LiClO{sub 4}/PC content. PM results indicate that the increase in PEO ratio increases the crystallinity of the PEO-WPU(PTMG) films. When LiClO{sub 4}/PC is added, the increase in PEO ratio results in an increase in conductivity. The CE comprising 33% PEO, 17% WPU(PTMG), and 50% LiClO{sub 4}/PC exhibits conductivities as high as Ca. {approximately}10{sup {minus}2} S/cm at 85 C and 5 {times} 10{sup {minus}3} S/cm at 15 C.

  2. Linearity and additivity in cluster-induced sputtering: A molecular-dynamics study of van der Waals bonded systems

    SciTech Connect

    Anders, Christian; Urbassek, Herbert M.; Johnson, Robert E.

    2004-10-15

    Using molecular-dynamics simulation, we study sputtering of a condensed-gas solid induced by the impact of atomic clusters with sizes 1{<=}n{<=}10{sup 4}. Above a nonlinear onset regime, we find a linear increase of the sputter yield Y with the total energy E of the bombarding cluster. The fitting coefficients in the linear regime depend only on the cluster size n such that for fixed bombardment energy, sputtering decreases with increasing cluster size n. We find that to a good approximation the sputter yield in this regime obeys an additivity rule in cluster size n such that doubling the cluster size at the same cluster velocity amounts to doubling the sputter yield. The sputter-limiting energy {epsilon}{sub s} is introduced which separates erosion ({epsilon}>{epsilon}{sub s}) from growth ({epsilon}<{epsilon}{sub s}) under cluster impact.

  3. Study on Antiwear and Repairing Performances about Mass of Nano-copper Lubricating Additives to 45 Steel

    NASA Astrophysics Data System (ADS)

    Wang, X. L.; Yin, Y. L.; Zhang, G. N.; Wang, W. Y.; Zhao, K. K.

    Nano-copper usually serve for lubricating additives in tribology field. The antiwear and reducing friction performances both basic lubrication oil and basic lubrication oil with nano-copper in different mass were tested by friction wear test machine. The morphologies and the main elements of worn surfaces were analyzed by SEM. The results indicated that nano-copper could improve tribology performances of basic lubrication oil. Comparing with base lubrication oil, the mass is 0.15% of nano-copper, the friction coefficient and the worn trace width can be reduced 34% and 32% respectively. Nano-copper can form self-repairing film in lubrication oil which availably separates the friction materials in friction process. Therefore, nano-copper has wonderful antiwear, reducing friction and self-repairing performances. And the function mechanism of Cu nanoparticles is studied in the paper.

  4. An Investigation of Factors Determining the Study Abroad Destination Choice: A Case Study of Taiwan

    ERIC Educational Resources Information Center

    Lee, Cheng-Fei

    2014-01-01

    Previous studies on the field of education abroad have mainly focused on the factors influencing the mobility of international students from developing to developed countries and very few have been conducted to investigate the factors influencing the flow of international students to the Asia Pacific region. As a piece of country-specific…

  5. An Investigation on Teaching Materials Used in Social Studies Lesson

    ERIC Educational Resources Information Center

    Saglam, Halil Ibrahim

    2011-01-01

    The purpose of this study is to analyze the teaching materials employed during social studies lessons on the basis of certain variables. Specifically, the researcher tried to find out whether teachers' gender, service length, having a personal computer, receiving an in-service training regarding the use of teaching materials, having an interest on…

  6. Investigating the Effectiveness of a Study Skills Training Programme

    ERIC Educational Resources Information Center

    Sikhwari, T. D.; Pillay, J.

    2012-01-01

    Various studies have shown that the school system in South Africa is continually producing learners who are inadequately prepared for higher education studies, particularly schools in disadvantaged environments. The University of Venda (UNIVEN) is situated in an educationally disadvantaged environment. Most of the students who enroll at this…

  7. Evidence of Rapidly Warming Rivers in the UK from an Extensive Additive Modelling Study at the National Scale Using R

    NASA Astrophysics Data System (ADS)

    Simpson, G. L.

    2011-12-01

    River water temperature data exhibit non-linear behaviour over the past 50 or so years. Standard techniques for identifying and quantifying trends have centred around the use of linear regression and Mann-Kendall and Thiel-Sen procedures. Observational data from UK rivers suggest that temperatures are far more variable then assumed under these statistical models. In a national-scale assessment of the response of riverine systems to global climatic change, an additive model framework was employed to model patterns in water temperatures from a large database of temporal observational data. Models were developed using R, which allowed for the deployment of cutting-edge additive modelling techniques to describe trends at 2773 sites across England and Wales, UK. At a subset of sites, additive models were used to model long-term trends, trends within seasons and the long-term variation in the seasonal pattern of water temperatures. Changes in water temperature have important consequences for aquatic ecology, with some species being particularly sensitive even to small shifts in temperature during some or all of their lifecycle. While there are many studies reporting increasing regional and global air temperatures, evidence for changes in river water temperature has thus far been site specific and/or from sites heavily influenced by human activities that could themselves lead to warming. Here I present selected results from a national-scale assessment of changing river water temperatures, covering the whole of England and Wales, comprising data from 2,773 locations. Positive trends in water temperature were observed at 86% of sites. At a subset of sites, seasonal trend models were developed, which showed that 90% of locations demonstrated statistically significant increases in water temperature during Autumn and Winter periods. Multivariate smoothers, that allow for within-year and longer-term trend interactions in time, suggest that periods of warmer waters now extend

  8. Tularemia Outbreak Investigation in Kosovo: Case Control and Environmental Studies

    PubMed Central

    Dedushaj, Isuf; Gjini, Ardiana; Jorgensen, Tine Rikke; Cotter, Benvon; Lieftucht, Alfons; D’Ancona, Fortunato; Dennis, David T.; Kosoy, Michael A.; Mulliqi-Osmani, Gjyle; Grunow, Roland; Kalaveshi, Ariana; Gashi, Luljeta; Humolli, Isme

    2002-01-01

    A large outbreak of tularemia occurred in Kosovo in the early postwar period, 1999-2000. Epidemiologic and environmental investigations were conducted to identify sources of infection, modes of transmission, and household risk factors. Case and control status was verified by enzyme-linked immunosorbent assay, Western blot, and microagglutination assay. A total of 327 serologically confirmed cases of tularemia pharyngitis and cervical lymphadenitis were identified in 21 of 29 Kosovo municipalities. Matched analysis of 46 case households and 76 control households suggested that infection was transmitted through contaminated food or water and that the source of infection was rodents. Environmental circumstances in war-torn Kosovo led to epizootic rodent tularemia and its spread to resettled rural populations living under circumstances of substandard housing, hygiene, and sanitation. PMID:11749751

  9. Comparative study of GaN mesa etch characteristics in Cl{sub 2} based inductively coupled plasma with Ar and BCl{sub 3} as additive gases

    SciTech Connect

    Rawal, Dipendra Singh Arora, Henika; Sehgal, Bhupender Kumar; Muralidharan, Rangarajan

    2014-05-15

    GaN thin film etching is investigated and compared for mesa formation in inductively coupled plasma (ICP) of Cl{sub 2} with Ar and BCl{sub 3} gas additives using photoresist mask. Etch characteristics are studied as a function of ICP process parameters, viz., ICP power, radio frequency (RF) power, and chamber pressure at fixed total flow rate. The etch rate at each ICP/RF power is 0.1–0.2 μm/min higher for Cl{sub 2}/Ar mixture mainly due to higher Cl dissociation efficiency of Ar additive that readily provides Cl ion/radical for reaction in comparison to Cl{sub 2}/BCl{sub 3} mixture. Cl{sub 2}/Ar mixture also leads to better photoresist mask selectivity. The etch-induced roughness is investigated using atomic force microscopy. Cl{sub 2}/Ar etching has resulted in lower root-mean-square roughness of GaN etched surface in comparison to Cl{sub 2}/BCl{sub 3} etching due to increased Ar ion energy and flux with ICP/RF power that enhances the sputter removal of etch product. The GaN surface damage after etching is also evaluated using room temperature photoluminescence and found to be increasing with ICP/RF power for both the etch chemistries with higher degree of damage in Cl{sub 2}/BCl{sub 3} etching under same condition.

  10. Studies on the synthesis of 1-substituted uracils, radical-induced cyclization of 1,6-diolefins, and the addition of nucleophiles to fullerenes

    SciTech Connect

    Naim, A.

    1992-01-01

    The reaction of 2-propanol solution of 1,6-diolefins was investigated. The gamma radiolysis of 2-propanol generates 2-hydroxy-2-propyl radical and a hydrogen atom. The addition of 2-hydroxy-2-propyl radical to a double bond forms a 5-hexenyl radical, which subsequently cyclizes to generate the methylcyclopentyl radical. The formation of product in the gamma radiolysis of 2-propanol + 1,6-diolefins is the same as the photolysis of a mixture of 2-propanol + acetone + 1,6-diolefins. On the basis of experimental findings, the major isomer concluded was cis. The monomer diallyldimethylammonium bromide, which undergoes facile polymerization in the presence of free radicals, was also cyclized to give monomeric products. The addition of a variety of nucleophiles to fullerenes was also studied. Both C[sub 60]/C[sub 70] react with KOH and degrade in contact with air. Their reactions are reversible under vacuum. Regeneration of C[sub 60] is quantitative while C[sub 70] in only 72%. The C[sub 70] is more reactive toward KOH than C[sub 60], which led to development of a method to obtain pure C[sub 60] from C[sub 60]/C[sub 70]. Besides KOH, the reaction of KF, NaNH[sub 2], N[sub 2]CHCO[sub 2]CH[sub 2]CH[sub 3] and CH[sub 2]N[sub 2] with the fullerenes were also investigated.

  11. Presentation and clinical investigation of mitochondrial respiratory chain disease. A study of 51 patients.

    PubMed

    Jackson, M J; Schaefer, J A; Johnson, M A; Morris, A A; Turnbull, D M; Bindoff, L A

    1995-04-01

    Defects of the mitochondrial respiratory chain are associated with a great variety of clinical disorders. Whilst recognition of these conditions is increasing, the need for sophisticated biochemical and molecular studies has tended to limit both their investigation and diagnosis to a few specialist centres. Using a group of 51 patients with histochemically, biochemically and/or genetically defined respiratory chain defects, we have examined both the clinical heterogeneity of these disorders and how they may be investigated most effectively in non-specialist centres. We evaluated the use of the following routinely available clinical investigations--fasting intermediary metabolites (lactate, pyruvate, ketone bodies, etc.) in blood and cerebrospinal fluid, serum creatine kinase estimation, EMG, EEG, CT, MRI and histological/histochemical muscle biopsy analysis. Our studies show that, in addition to well-recognized syndromes (e.g. chronic progressive external ophthalmoplegia, mitochondrial encephalopathy lactic acidosis and stroke like episodes, and myoclonus epilepsy with ragged red-fibres, a significant number of patients present with non-specific encephalopathic disorders. Furthermore, even within those categories of respiratory chain disease which have been genetically defined, a wide variation of presenting symptoms and signs were found. Where there was initial doubt concerning the diagnosis, the following clinical features were helpful in suggesting respiratory chain disease: ophthalmoplegia; a maternal pattern of inheritance; the presence of myopathy or deafness in association with encephalopathy. Of the clinical investigations we assessed, elevated lactate in blood or cerebrospinal fluid and low density lesions in the basal ganglia were helpful in identifying patients with respiratory chain dysfunction. Histochemical analysis of muscle was, however, the single most useful investigation being diagnostic in patients with chronic progressive external

  12. A high precision study of the electrolyte additives vinylene carbonate, vinyl ethylene carbonate and lithium bis(oxalate)borate in LiCoO2/graphite pouch cells

    NASA Astrophysics Data System (ADS)

    Wang, David Yaohui; Sinha, N. N.; Burns, J. C.; Petibon, R.; Dahn, J. R.

    2014-12-01

    The effects of three well-known electrolyte additives, used singly or in combination, on LiCoO2/graphite pouch cells has been investigated using the ultra high precision charger (UHPC) at Dalhousie University, electrochemical impedance spectroscopy (EIS) and long term cycling Vinylene carbonate (VC), vinyl ethylene carbonate (VEC), and lithium bis(oxalato) borate (LiBOB) were chosen for study. The results show that combinations of electrolyte additives that act synergistically can be more effective than a single electrolyte additive. However, simply using 2% VC yielded cells very competitive in coulombic efficiency (CE), charge endpoint capacity slippage and charge transfer resistance (Rct). For cells with 1% LiBOB and VC (1, 2, 4 or 6%), adding VC above 2% does not increase the CE, but increases the electrode charge transfer impedances. Rct for cells containing 1% LiBOB and VEC (0.5, 1 or 4%) decreased after long term cycling (1800 h), compared to that tested after the UHPC cycling (500 h) indicating that VEC might be useful for the design of power cells. However, the opposite behaviour (increasing Rct with cycle number) was observed for the control cells or cells containing LiBOB and/or VC.

  13. Effect of addition of magnesium to local anesthetics for peribulbar block: A prospective randomized double-blind study

    PubMed Central

    Sinha, R; Sharma, A; Ray, BR; Chandiran, R; Chandralekha, C; Sinha, R

    2016-01-01

    Background: Magnesium sulphate has been used along with local anesthetics in different regional blocks and found to be effective in decreasing the time of onset of the block and increasing the duration of the block. Objective: To evaluate the effect of addition of magnesium sulfate to standard local anesthetics mixture on the time for onset of the globe and lid akinesia for peribulbar block in ophthalmic surgeries. Materials and Methods: Sixty patients with American Society of Anesthesiologists status I to III undergoing ophthalmic surgery under peribulbar block were included in this study. Patients were randomized into two groups. Both the groups received 4.5 ml of 2% lidocaine, 4.5 ml of 0.5% bupivacaine with150 IU hyaluronidase. Group NS received normal saline 1 ml in the peribulbar block and Group MS, magnesium sulfate 50 mg in 1 ml normal saline. The onset of akinesia, satisfactory block and complications were observed by an independent observer. Results: Demographic data was statistically similar. In the Group NS at 3, 5, 10 and 15 min after the block, complete akinesia was seen in 0, 2, 11 and 28 patients respectively. In the Group MS, at 3, 5, 10 and 15 min after the block, complete akinesia was seen in 13, 23, 27 and 28 patients respectively. Patients received magnesium sulfate showed the statistically significant rapid onset of lid and globe akinesia than the control group till 10 min (P < 0.000). None of the patients needed a supplementary block and had complications during the surgery. Conclusion: Addition of 50 mg of magnesium sulfate to the lidocaine-bupivacaine mixture for peribulbar block decreases the onset of akinesia without any obvious side effect. PMID:26955313

  14. Can homeopathy bring additional benefits to thalassemic patients on hydroxyurea therapy? Encouraging results of a preliminary study.

    PubMed

    Banerjee, Antara; Chakrabarty, Sudipa Basu; Karmakar, Susanta Roy; Chakrabarty, Amit; Biswas, Surjyo Jyoti; Haque, Saiful; Das, Debarsi; Paul, Saili; Mandal, Biswapati; Naoual, Boujedaini; Belon, Philippe; Khuda-Bukhsh, Anisur Rahman

    2010-03-01

    Several homeopathic remedies, namely, Pulsatilla Nigricans (30th potency), Ceanothus Americanus (both mother tincture and 6th potency) and Ferrum Metallicum (30th potency) selected as per similia principles were administered to 38 thalassemic patients receiving Hydroxyurea (HU) therapy for a varying period of time. Levels of serum ferritin (SF), fetal hemoglobin (HbF), hemoglobin (Hb), platelet count (PC), mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), mean corpuscular hemoglobin (MCH), white blood cell (WBC) count, bilirubin content, alanine amino transferase (ALT), aspartate amino transferase (AST) and serum total protein content of patients were determined before and 3 months after administration of the homeopathic remedies in combination with HU to evaluate additional benefits, if any, derived by the homeopathic remedies, by comparing the data with those of 38 subjects receiving only HU therapy. Preliminary results indicated that there was a significant decrease in the SF and increase in HbF levels in the combined, treated subjects. Although the changes in other parameters were not so significant, there was a significant decrease in size of spleen in most patients with spleenomegaly and improvement in general health conditions along with an increased gap between transfusions in most patients receiving the combined homeopathic treatment. The homeopathic remedies being inexpensive and without any known side-effects seem to have great potentials in bringing additional benefits to thalassemic patients; particularly in the developing world where blood transfusions suffer from inadequate screening and fall short of the stringent safety standards followed in the developed countries. Further independent studies are encouraged. PMID:18955271

  15. Additions and corrections to the bibliography of geologic studies, Columbia Plateau (Columbia River Besalt) and adjacent Areas, in Idaho, 1980

    SciTech Connect

    Strowd, W.

    1980-01-01

    This bibliography is an update to Idaho Bureau of Mines and Geology Open-File Report 78-6, Bibliography of Geological Studies, Columbia Plateau (Columbia River Basalt Group) and adjacent areas in Idaho (also known as Rockwell Hanford Operations' contractor report RHO-BWI-C-44). To keep the original document current, this additions and corrections report was prepared for the Basalt Waste Isolation Project of Rockwell Hanford Operations. This update is supplementary; therefore, references cited in the original document have not been included here. What is included are materials that have become available since the original publication and pertinent literature that had originally been overlooked. Accompany this updated bubliography are index maps that show locations of geologic studies and geochemical petrographic, remanent paleomagnetic, and radiometric age-dated sites within the Columbia River Basalt Group field within Idaho; also identified are archeological sites, test wells, mines, quarries, and other types of excavations. References on the index maps are keyed to the bibliography and cover the Spokane, Pullman, Hamilton, Grangeville, Elk City, Baker, Boise, and Jordan Valley Army Map Service two-degree quadrangles.

  16. Safety evaluation studies of SGF gum--a potential food additive from the seed of Sesbania cannabina.

    PubMed

    Li, X L; Xu, E Y; Xu, G C; Shang, R M; Wang, Y M; Chen, J; Huang, F C

    1988-01-01

    SGF gum, derived from the plant Sesbania cannabina, has properties very similar to those of guar gum. Because it is much cheaper than guar, SGF gum is of interest as a possible new food additive. It has therefore been tested in rats for acute, short-term and subchronic toxicity, teratogenicity and effects on reproductive performance, and a 1% concentration in the diet has been identified as the no-effect level. The tests complied with the guidelines issued by the Chinese authorities. Mutagenicity studies, Ames tests and a micronucleus test gave negative results, and a dominant lethal test in mice was negative at the 1% dietary level, although at 5 and 10% the results were equivocal. No adverse changes were elicited in 23 human volunteers who consumed a total of 960 mg SGF gum during a 30-day period during which they consumed, daily, 80 g ice-cream containing 0.04% SGF gum instead of the usual thickener. On the basis of applying a 100-fold safety factor to the findings in the animal studies, an acceptable human daily intake of 6 mg/kg is suggested. PMID:3209133

  17. Investigation of the hybrid molecular probe for intracellular studies

    PubMed Central

    Martinez, Karen; Medley, Colin D.; Yang, Chaoyong James; Tan, Weihong

    2009-01-01

    Monitoring gene expression in vivo is essential to the advancement of biological studies, medical diagnostics, and drug discovery. Adding to major efforts in developing molecular probes for mRNA monitoring, we have recently developed an alternative tool, the hybrid molecular probe (HMP). To optimize the probe, a series of experiments were performed to study the properties of HMP hybridization kinetics and stability. The results demonstrated the potential of the HMP as a prospective tool for use in both hybridization studies and in vitro and in vivo analyses. The HMP has shown no tendency to produce false positive signals, which is a major concern for living cell studies. Moreover, HMP has shown the ability to detect the mRNA expression of different genes inside single cells from both basal and stimulated genes. As an effective alternative to conventional molecular probes, the proven sensitivity, simplicity, and stability of HMPs show promise for their use in monitoring mRNA expression in living cells. PMID:18421445

  18. Interrelations that foster learning: An investigation of two correlational studies.

    PubMed

    Phan, Huy P

    2016-06-01

    The theoretical tenets of academic engagement, as outlined by Schaufeli and colleagues, have received limited attention. There is credence to indicate that Schaufeli et al.'s conceptualization has educational implications. Extending this avenue of inquiry, we report two longitudinal studies that explore the motivation-related attributes of engagement within the framework of self-efficacy. A number of research questions were developed for examination-for example, does enactive learning experience influence academic achievement, via students' engrossment (i.e. absorption) of a subject matter? Does students' sense of resilience and persistence (i.e. vigor) heighten their self-efficacy beliefs for academic learning? For the two studies (Study 1: 311 Year 11 students; Study 2: 249 Year 12 students), utilizing different cohorts, we measured these constructs at multiple time points. Existing Likert-scale inventories were administered repeatedly, and data collected were analysed using causal modeling procedures. MPlus 7.2 yielded a number of key findings-for example: (a) the positive impact of Time 1 enactive learning experience on Time 2 absorption and vigor, (b) the positive impact of Time absorption on Time 3 self-efficacy, (c) the positive impact of Time 2 absorption on Time 4 achievement and (d) the positive impact of Time 1 self-efficacy on Time 2 absorption and vigor. PMID:25501749

  19. An Investigative Study into Pupils' Perceptions of Europe.

    ERIC Educational Resources Information Center

    Convery, Anne; And Others

    1997-01-01

    Examines the perceptions of European teenagers living in Europe regarding that continent. The study focuses on their declared knowledge sources, attitudes towards a European identity and second language learning and future aspirations. The article discusses the role of schools, the media, and the home environment in shaping the perceptions of…

  20. Investigating Young Children's Use of Reading Strategies: A Longitudinal Study

    ERIC Educational Resources Information Center

    Kragler, Sherry; Martin, Linda; Schreier, Virginia

    2015-01-01

    In this three-year study, the authors examined the reading strategy use of 16 primary-grade students as they read fiction and expository text. The students (9 boys and 7 girls) represented low, average, and above-average readers. Structured interviews and observational data were collected each year as they progressed from first to third grade.…

  1. Environmental Studies Center Teacher Books. 6th Grade - River Investigation.

    ERIC Educational Resources Information Center

    Martin County Schools, Jensen Beach, FL. Environmental Studies Center.

    This teacher's guide, one of nine teacher packages developed for use in the sequential, hands-on, field-oriented, K-8 environmental education program of the Martin County Schools in Florida, was developed for use with elementary children in grade six prior to and after a visit to an environmental studies center located near an estuarine area. The…

  2. Environmental Studies Center Teacher Books. 8th Grade - Beach Investigation.

    ERIC Educational Resources Information Center

    Martin County Schools, Jensen Beach, FL. Environmental Studies Center.

    This teacher's guide, one of nine teacher packages developed for use in the sequential, hands-on, field-oriented, K-8 environmental education program of the Martin County Schools in Florida, was developed for use with secondary children in grade eight prior to and after a visit to an environmental studies center located near an estuarine area. The…

  3. Investigating Reported Data Practices in Early Childhood: An Exploratory Study

    ERIC Educational Resources Information Center

    Brawley, Susan; Stormont, Melissa A.

    2014-01-01

    The importance of collecting and using data for educational decision making is clear. However, little information has been gathered about the systematic collection and use of data in early childhood. The purpose of this study was to explore teacher perceptions of data collection practices in early childhood. Participants included 137 early…

  4. The Southern Community Cohort Study: Investigating Health Disparities

    PubMed Central

    Signorello, Lisa B.; Hargreaves, Margaret K.; Blot, William J.

    2010-01-01

    Summary Over 73,700 adults age 40–79, nearly 70% African American, were recruited at community health centers across 12 southeastern states; individual characteristics were recorded and biologic specimens collected at baseline for later follow-up. The Southern Community Cohort Study is a unique national resource for assessing determinants of racial/ethnic differentials in diseases. PMID:20173283

  5. Investigating Cooperative Behavior in Ecological Settings: An EEG Hyperscanning Study.

    PubMed

    Toppi, Jlenia; Borghini, Gianluca; Petti, Manuela; He, Eric J; De Giusti, Vittorio; He, Bin; Astolfi, Laura; Babiloni, Fabio

    2016-01-01

    The coordinated interactions between individuals are fundamental for the success of the activities in some professional categories. We reported on brain-to-brain cooperative interactions between civil pilots during a simulated flight. We demonstrated for the first time how the combination of neuroelectrical hyperscanning and intersubject connectivity could provide indicators sensitive to the humans' degree of synchronization under a highly demanding task performed in an ecological environment. Our results showed how intersubject connectivity was able to i) characterize the degree of cooperation between pilots in different phases of the flight, and ii) to highlight the role of specific brain macro areas in cooperative behavior. During the most cooperative flight phases pilots showed, in fact, dense patterns of interbrain connectivity, mainly linking frontal and parietal brain areas. On the contrary, the amount of interbrain connections went close to zero in the non-cooperative phase. The reliability of the interbrain connectivity patterns was verified by means of a baseline condition represented by formal couples, i.e. pilots paired offline for the connectivity analysis but not simultaneously recorded during the flight. Interbrain density was, in fact, significantly higher in real couples with respect to formal couples in the cooperative flight phases. All the achieved results demonstrated how the description of brain networks at the basis of cooperation could effectively benefit from a hyperscanning approach. Interbrain connectivity was, in fact, more informative in the investigation of cooperative behavior with respect to established EEG signal processing methodologies applied at a single subject level. PMID:27124558

  6. A study of methods to investigate nozzle boundary layer transition

    NASA Technical Reports Server (NTRS)

    Pauley, Laura L.

    1991-01-01

    To further investigate nozzle flow, numerical computations are employed. The computations produce complete flow velocity and temperature fields within the nozzle. As a check, these results can be compared with experimental data at the wall. Once an accurate numerical scheme has been validated, it can be used as a design tool to predict the performance of other nozzle designs without the cost of experimental testing. Typically, the numerical analysis assumes either a laminar boundary layer or a fully turbulent boundary layer which is steady and two-dimensional. Boundary layer transition is not considered. Computing both the completely laminar boundary layer and the completely turbulent boundary layer conditions gives the minimum and maximum wall heat flux possible for a specified geometry. When the experimental heat flux measurements lie between these two values, the nature of the boundary layer is unknown. The boundary layer may have transitioned from laminar to turbulent; three-dimensional structures may be present in the boundary layer, or the inlet flow conditions may not be correctly specified in the computation.

  7. CCD photometric study and period investigation of V508 Oph

    SciTech Connect

    Xiang, Fu-Yuan; Yu, Yun-Xia; Xiao, Ting-Yu

    2015-02-01

    In this paper, new CCD photometric observations of V508 Oph obtained in 2009 and 2010 at the Xinglong Observatory are presented. From the new observations, six new times of minimum light were derived. The light curves were analyzed by using the 2003 version of the Wilson–Devinney program. It is found that the asymmetric light curves can be modeled by a hot spot on the secondary component. The degree of overcontact is 15.4%, implying that the system is a shallow-contact binary. Combining the new times of minimum light with the photoelectric and CCD data compiled from the database, we investigate its orbital period. The results show that the orbital period may be undergoing multiple changes: a long-term decrease at a rate of dP/dt=−(1.502±0.063)×10{sup −7} days year{sup −1}, and a small periodic variation with a period of 24.27(±0.34) years. Since V508 Oph is an overcontact system and both components are late-type stars, we discuss the possible connection between the mass transfer, magnetic activity, the third body, and the orbital period changes.

  8. Investigating Cooperative Behavior in Ecological Settings: An EEG Hyperscanning Study

    PubMed Central

    Petti, Manuela; He, Eric J.; De Giusti, Vittorio; He, Bin; Astolfi, Laura; Babiloni, Fabio

    2016-01-01

    The coordinated interactions between individuals are fundamental for the success of the activities in some professional categories. We reported on brain-to-brain cooperative interactions between civil pilots during a simulated flight. We demonstrated for the first time how the combination of neuroelectrical hyperscanning and intersubject connectivity could provide indicators sensitive to the humans’ degree of synchronization under a highly demanding task performed in an ecological environment. Our results showed how intersubject connectivity was able to i) characterize the degree of cooperation between pilots in different phases of the flight, and ii) to highlight the role of specific brain macro areas in cooperative behavior. During the most cooperative flight phases pilots showed, in fact, dense patterns of interbrain connectivity, mainly linking frontal and parietal brain areas. On the contrary, the amount of interbrain connections went close to zero in the non-cooperative phase. The reliability of the interbrain connectivity patterns was verified by means of a baseline condition represented by formal couples, i.e. pilots paired offline for the connectivity analysis but not simultaneously recorded during the flight. Interbrain density was, in fact, significantly higher in real couples with respect to formal couples in the cooperative flight phases. All the achieved results demonstrated how the description of brain networks at the basis of cooperation could effectively benefit from a hyperscanning approach. Interbrain connectivity was, in fact, more informative in the investigation of cooperative behavior with respect to established EEG signal processing methodologies applied at a single subject level. PMID:27124558

  9. Biocompatibility of Ricinus communis polymer with addition of calcium carbonate compared to titanium. Experimental study in guinea pigs

    PubMed Central

    Graça, Yorgos Luiz Santos De Salles; Opolski, Ana Cristina; Barboza, Barbara Evelin Gonçalves; Erbano, Bruna Olandoski; Mazzaro, Caroline Cantalejo; Klostermann, Flávia Caroline; Sucharski, Enéas Eduardo; Kubrusly, Luiz Fernando

    2014-01-01

    Objective The aim of the present investigation was to determine whether the difference in inflammatory tissue reaction between the Riccinus communis (castor) polymer with calcium carbonate and the titanium implant is statistically significant. Methods Thirty-two Cavia porcellus were allocated into four groups of eight animals each. We implanted the two types of materials in the retroperitoneal space of all the animals. They were euthanized at 7, 20, 30 and 40 days after surgery, and an histological study of the samples was conducted. Results All implants showed characteristics of chronic inflammation regardless of the material and timepoint of evaluation. There was no statistically significant difference between Pm+CaCO3 and Ti with regard to the presence of granulation tissue, tissue congestion, histiocytes, lymphocytes, neutrophils, giant cells, and fibrosis (P> 0.05). Conclusion The castor oil polymer plus calcium carbonate implant was not statistically different from the titanium implant regarding inflammatory tissue reaction. PMID:25140479

  10. Building Effective Scientist-Teacher Partnerships: A Case Study Investigation

    NASA Astrophysics Data System (ADS)

    Walker, B. A.; Hall, M. K.; Regens, N. L.

    2005-12-01

    Scientist-teacher partnerships provide opportunities for scientists to become better educators and teachers to increase their science content knowledge, but few accounts exist about how partnerships evolve and why some succeed and others fail. We investigated these questions in the context of an NSF GK-12 program that pairs graduate and undergraduate science and math students (fellows) with K-12 teachers. Using a variety of data sources, we found several patterns that were influential across the majority of partnerships. Aligned, partnership-centered goals and expectations were most conducive to productive relationships. A desire and commitment to collaborate and a willingness to communicate openly were also essential. Differences in the rigidity and intensity of the K-12 and university schedules and working with multiple teachers made collaboration difficult due to lack of planning time. Mutual investment manifested itself in several ways among partnerships including collaboration on teaching, planning, and other classroom activities, exchange of resources, and exchange of constructive feedback. Fellows and teachers were most likely to invest themselves when they perceived that their contributions were invited and appreciated in and out of the classroom. In all cases, role ambiguity was a major barrier to partnership formation. Fellows employed numerous strategies to define their roles, but working collaboratively was possible only when roles were discussed and allowed to evolve. Fellows and teachers found it difficult to communicate directly about dissatisfaction. While each partnership was unique, these major patterns influencing the success of a partnership occur in many situations and thus appear transferable. Regardless of outcome, partners felt as though they benefited significantly from this experience. Our results may be applied to similar partnership programs to improve project design and enhance the sustainability of relationships between scientists and

  11. Investigation of the O+allyl addition/elimination reaction pathways from the OCH{sub 2}CHCH{sub 2} radical intermediate

    SciTech Connect

    FitzPatrick, Benjamin L.; Lau, K.-C.; Butler, Laurie J.; Lee, S.-H.; Lin, Jim Jr-Min

    2008-08-28

    These experiments study the preparation of and product channels resulting from OCH{sub 2}CHCH{sub 2}, a key radical intermediate in the O+allyl bimolecular reaction. The data include velocity map imaging and molecular beam scattering results to probe the photolytic generation of the radical intermediate and the subsequent pathways by which the radicals access the energetically allowed product channels of the bimolecular reaction. The photodissociation of epichlorohydrin at 193.3 nm produces chlorine atoms and c-OCH{sub 2}CHCH{sub 2} radicals; these undergo a facile ring opening to the OCH{sub 2}CHCH{sub 2} radical intermediate. State-selective resonance-enhanced multiphoton ionization (REMPI) detection resolves the velocity distributions of ground and spin-orbit excited state chlorine independently, allowing for a more accurate determination of the internal energy distribution of the nascent radicals. We obtain good agreement detecting the velocity distributions of the Cl atoms with REMPI, vacuum ultraviolet (VUV) photoionization at 13.8 eV, and electron bombardment ionization; all show a bimodal distribution of recoil kinetic energies. The dominant high recoil kinetic energy feature peaks near 33 kcal/mol. To elucidate the product channels resulting from the OCH{sub 2}CHCH{sub 2} radical intermediate, the crossed laser-molecular beam experiment uses VUV photoionization and detects the velocity distribution of the possible products. The data identify the three dominant product channels as C{sub 3}H{sub 4}O (acrolein)+H, C{sub 2}H{sub 4}+HCO (formyl radical), and H{sub 2}CO (formaldehyde)+C{sub 2}H{sub 3}. A small signal from C{sub 2}H{sub 2}O (ketene) product is also detected. The measured velocity distributions and relative signal intensities at m/e=27, 28, and 29 at two photoionization energies show that the most exothermic product channel, C{sub 2}H{sub 5}+CO, does not contribute significantly to the product branching. The higher internal energy onset of the

  12. Offpost operable unit remedial investigation/endangerment assessment/feasibility study, draft final work plan

    SciTech Connect

    1989-12-01

    This document presents the scope of work for additional data collection activities and interpretive reports to be performed in the off-post operable unit (OU) for preparation of: (1) Addendum to the final remedial investigation report; (2)` Revision of the draft final endangerment assessment/feasibility study. The plan is divided into the following sections: (1) Requirements for the RI addendum - technical approach and data collection program for the RI addendum - technical approach and data collection program for ground water, soil, sediment, biota, air; (2) Revision of the endagerment assessment - items that need to be reevaluated; (3) Revision of the feasibility study - evaluation of different media and ARAR`s development of remedial alternatives; (4) Schedule and description of deliverables. Appendix a contains a detailed approach for the 96th avenue risk assessment.

  13. Polyimide processing additives

    NASA Technical Reports Server (NTRS)

    Pratt, J. R.; St. Clair, T. L.; Burks, H. D.; Stoakley, D. M.

    1987-01-01

    A method has been found for enhancing the melt flow of thermoplastic polyimides during processing. A high molecular weight 422 copoly(amic acid) or copolyimide was fused with approximately 0.05 to 5 pct by weight of a low molecular weight amic acid or imide additive, and this melt was studied by capillary rheometry. Excellent flow and improved composite properties on graphite resulted from the addition of a PMDA-aniline additive to LARC-TPI. Solution viscosity studies imply that amic acid additives temporarily lower molecular weight and, hence, enlarge the processing window. Thus, compositions containing the additive have a lower melt viscosity for a longer time than those unmodified.

  14. Work plan addendum for the remedial investigation and feasibility study of the Salmon Site

    SciTech Connect

    1995-11-01

    This document is intended as an addendum to the Remedial Investigation and Feasibility Study (RI/FS) Work Plan for the Salmon Site (SS) (formerly the Tatum Dome Test Site) Lamar County, Mississippi. The original work plan - Remedial Investigation and Feasibility Study of the Tatum Dome Test Site, Lamar County, Mississippi (herein after called the Work Plan) was approved by the state of Mississippi in 1992 and was intended as the operative document for investigative activities at the Tatum Dome Test Site. Subsequent to the approval of the document a series of activities were undertaken under the auspices of the work plan. This document is organized in the same manner as the original work plan: (1) Introduction; (2) Site Background and History; (3) Initial Evaluation; (4) Data Quality Objectives; (5) RI/FS Tasks; (6) Project Schedule; (7) Project Management; and (8) Reference. This addendum will identify changes to the original work plan that are necessary because of additional information acquired at the SS. This document is not intended to replace the work plan, rather, it is intended to focus the remaining work in the context of additional site knowledge gained since the development of the original work plan. The U.S. Department of Energy (DOE) is conducting a focused and phased site characterization as a part, of the RI/FS. The RI/FS is the methodology under the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) for evaluating hazardous waste sites on the National Priorities List (NPL). The SS is not listed on the NPL, but DOE has voluntarily elected to conduct the evaluation of the SS in accordance with CERCLA.

  15. An Electron Microscopy Investigation of the Transient Stage Oxidation Products in an Fe-22Cr Alloy with Ce and La Additions Exposed to Dry Air at 1073 K (800 °C)

    SciTech Connect

    Jingxi Zhu; Laura Fernandez-Diaz; Gordon Holcomb; Paul Jablonski; Christopher Cowen; David Lauglin; and Sridhar Seetharaman

    2010-10-01

    In this study, the effects of Ce (270 ppm) and La (120 ppm) mischmetal additions on the transient oxidation of an Fe-22Cr alloy were investigated. The oxidation process was imaged in situ using a confocal scanning laser microscope. The oxidation microstructures were studied by scanning electron microscopy, energy dispersive X-ray analysis, and transmission electron microscopy with the help of focused ion beam in situ lift-out specimen preparation. The Ce and La, referred to as reactive elements, were found in nonmetallic inclusion particles in the forms of oxides, sulfides, and phosphates. An affected zone formed around rare earth (RE)-containing inclusion particles at the alloy free surface during the transient oxidation. This zone consisted of an internal Cr-oxide formed beneath the particle as well as a thinner external oxide scale on the surface compared with the surroundings. The relation of this microstructure to oxidation kinetics is discussed. With time, the RE elements diffused into the scale from the RE particles on the alloy surface during the high-temperature exposure. A diffusion mechanism is presented to describe these observations.

  16. Studies of photodynamic therapy: Investigation of physiological mechanisms and dosimetry

    NASA Astrophysics Data System (ADS)

    Woodhams, Josephine Helen

    Photodynamic therapy (PDT) is a treatment for a range of malignant and benign lesions using light activated photosensitising drugs in the presence of molecular oxygen. PDT causes tissue damage by a combination of processes involving the production of reactive oxygen species (in particular singlet oxygen). Since the PDT cytotoxic effect depends on oxygen, monitoring of tissue oxygenation during PDT is important for understanding the basic physiological mechanisms and dosimetry of PDT. This thesis describes the use of non-invasive, optical techniques based on visible light reflectance spectroscopy for the measurement of oxy- to deoxyhaemoglobin ratio or haemoglobin oxygen saturation (HbSat). HbSat was monitored at tissue sites receiving different light dose during aluminium disulphonated phthalocyanine (AIS2PC) PDT. Results are presented on real time PDT-induced changes in HbSat in normal tissue (rat liver) and experimental tumours, and its correlation with the final biological effect under different light regimes, including fractionated light delivery. It was found to some extent that changes in HbSat could indicate whether the tissue would be necrotic after PDT and it was concluded that online physiological dosimetry is feasible for PDT. The evaluation of a new photosensitiser for PDT called palladium-bacteriopheophorbide (WST09) has been carried out in normal and tumour tissue in vivo. WST09 was found to exert a strong PDT effect but was active only shortly after administration. WST09 produced substantial necrosis in colonic tumours whilst only causing a small amount of damage to the normal colon under certain conditions indicating a degree of selectivity. Combination therapy with PDT for enhancing the extent of PDT-induced damage has been investigated in vivo by using the photochemical internalisation (PCI) technique and Type 1 mechanism enhanced phototoxicity with indole acetic acid (IAA). PCI of gelonin using AIS2PC PDT in vivo after systemic administration of

  17. A mechanistic investigation on the formation and rearrangement of silaspiropentane: A theoretical study.

    PubMed

    Yildiz, Cem Burak; Azizoglu, Akin

    2016-07-01

    The formation of silaspiropentane from addition of singlet silacyclopropylidene 1 and silacyclopropylidenoid 8 to ethylene has been investigated separately at the B3LYP, X3LYP, WB97XD, and M05-2X theories using the 6-31+G(d,p) basis set. The silacycloproylidenoid addition follows a stepwise route. In contrast, a concerted mechanism occurs for silacyclopropylidene addition. Moreover, the intramolecular rearrangements of silaspiropentane 9 to methylenesilacyclobutane 11 and 2-silaallene + ethylene 12 have been studied extensively. The required energy barrier for the isomerization of 9 to 10 was determined to be 44.0 kcal mol(-1) at the B3LYP/6-31+G(d,p) level. After formation of 10, the rearrangement to methylenesilacyclobutane 12 is highly exergonic by -15.9 kcal mol(-1), which makes this reaction promising. However, the conversion of 9 to 11 is calculated to be quite endergonic, by 26.5 kcal mol(-1). PMID:27312710

  18. Physicochemical investigations and stability studies of amorphous gliclazide.

    PubMed

    Jondhale, Shital; Bhise, Satish; Pore, Yogesh

    2012-06-01

    Gliclazide (GLI), a poorly water-soluble antidiabetic, was transformed into a glassy state by melt quench technique in order to improve its physicochemical properties. Chemical stability of GLI during formation of glass was assessed by monitoring thin-layer chromatography, and an existence of amorphous form was confirmed by differential scanning calorimetry and X-ray powder diffractometry. The glass transition occurred at 67.5°C. The amorphous material thus generated was examined for its in vitro dissolution performance in phosphate buffer (pH 6.8). Surprisingly, amorphous GLI did not perform well and was unable to improve the dissolution characteristics compared to pure drug over entire period of dissolution studies. These unexpected results might be due to the formation of a cohesive supercooled liquid state and structural relaxation of amorphous form toward the supercooled liquid region which indicated functional inability of amorphous GLI from stability point of view. Hence, stabilization of amorphous GLI was attempted by elevation of T(g) via formation of solid dispersion systems involving comprehensive antiplasticizing as well as surface adsorption mechanisms. The binary and ternary amorphous dispersions prepared with polyvinylpyrrolidone K30 (as antiplasticizer for elevation of T (g)) and Aerosil 200® and/or Sylysia® 350 (as adsorbent) in the ratio of 1:1:1 (w/w) using kneading and spray-drying techniques demonstrated significant enhancement in rate and extent of dissolution of drug initially. During accelerated stability studies, ternary systems showed no significant reduction in drug dissolution performance over a period of 3 months indicating excellent stabilization of amorphous GLI. PMID:22382730

  19. [A STUDY INVESTIGATING THE FACTORS OF INTERNET ADDICTION].

    PubMed

    Puharić, Zrinka; Stašević, Ina; Ropac, Darko; Petričević, Nina; Jurišić, Irena

    2014-12-01

    The aim of the study was to explore the characteristics of Internet use among elementary school eighth-graders in the Bjelo- var-Bilogora County, to evaluate gender and sociodemographic differences, and to examine predictors for Internet addiction. The study included 437 (female 51%) eighth-graders, mean age 13.8 ± 0.5 years. An anonymous questionnaire was used to measure the participants' Internet use, the functions for which they used Internet, their parents' attitude towards the child's Internet use, and their signs of Internet addiction. Logistic regression was conducted to evaluate predictors for Internet addiction. The majority of children (71.5%) reported using Internet every day. Considering important risk factors of Internet addiction development, we found that 32% of children almost always stayed on-line longer than intended, 13% of boys and 4% of girls almost always neglected chores to spend more time on-line and 51.7% of children thought their life would be boring and uninteresting without the Internet. There was no significant difference between urban and rural students. In terms of the function for which they used the Internet, they were mostly engaged in on-line community/chat websites (70%), to listen to music and watch movies (81 %), and boys in gaming websites. Most of the students (43.4%) spent 1-2 hours daily on-line, 26.2% of students spent 3-4 hours on-line, and 9% spent more than 5 hours daily on-line. In conclusion, more public health preventive measures should be conducted to raise public awareness and concern about the negative effect of Internet use and Internet addiction, especially in the young population. PMID:26285469

  20. Surface modification of additive manufactured Ti6Al4V alloy with Ag nanoparticles: wettability and surface morphology study

    NASA Astrophysics Data System (ADS)

    Chudinova, E.; Surmeneva, M.; Koptioug, A.; Sharonova, A.; Loza, K.; Surmenev, R.

    2016-02-01

    In this work, the use of electrophoretic deposition to modify the surface of Ti6Al4V alloy fabricated via additive manufacturing technology is reported. Poly(vinylpyrrolidone) (PVP)-stabilized silver nanoparticles (AgNPs) had a spherical shape with a diameter of the metallic core of 100±20 nm and ζ -potential -15 mV. The AgNPs- coated Ti6Al4V alloy was studied in respect with its chemical composition and surface morphology, water contact angle, hysteresis, and surface free energy. The results of SEM microphotography analysis showed that the AgNPs were homogeneously distributed over the surface. Hysteresis and water contact angle measurements revealed the effect of the deposited AgNPs layer, namely an increased water contact angle and decreased contact angle hysteresis. However, the average water contact angle was 125° for PVP-stabilized-AgNPs-coated surface, whereas ethylene glycol gave the average contact angle of 17°. A higher surface energy is observed for AgNPs-coated Ti6Al4V surface (70.17 mN/m) compared with the uncoated surface (49.07 mN/m).

  1. Tropical Tropospheric Ozone from SHADOZ (Southern Hemisphere ADditional Ozonesondes) Network: A Project for Satellite Research, Process Studies, Education

    NASA Technical Reports Server (NTRS)

    Thompson, Anne M.; Witte, Jacquelyn C.; Oltmans, Samuel J.; Schmidlin, Francis J.; Coetzee, G. J. R.; Hoegger, Bruno; Kirchhoff, V. W. J. H.; Ogawa, Toshihiro; Kawakami, Shuji; Posny, Francoise

    2002-01-01

    The first climatological overview of total, stratospheric and tropospheric ozone in the southern hemisphere tropical and subtropics is based on ozone sounding data from 10 sites comprising the Southern Hemisphere Additional OZonesondes (SHADOZ) network. The period covered is 1998-2000. Observations were made over: Ascension Island; Nairobi, Kenya; Irene, South Africa; Reunion Island; Watukosek, Java; Fiji; Tahiti; American Samoa; San Cristobal, Galapagos; Natal, Brazil. Campaign data were collected on a trans-Atlantic oceanographic cruise and during SAFARI-2000 in Zambia. The ozone data, with simultaneous temperature profiles to approx. 7 hPa and relative humidity to approx. 200 hPa, reside at: . SHADOZ ozone time-series and profiles give a perspective on tropical total, stratospheric and tropospheric ozone. Prominent features are highly variable tropospheric ozone and a zonal wave-one pattern in total (and tropospheric) column ozone. Total, stratospheric and tropospheric column ozone amounts peak between August and November and are lowest between March and May. Tropospheric ozone variability over the Indian and Pacific Ocean displays influences of the Indian Ocean Dipole and convective mixing. Pollution transport from Africa and South America is a seasonal feature. Tropospheric ozone seasonality over the Atlantic Basin shows effects of regional subsidence and recirculation as well as biomass burning. Dynamical and chemical influences appear to be of comparable magnitude though model studies are needed to quantify this.

  2. Did the addition of concomitant chemotherapy to radiotherapy improve outcomes in hypopharyngeal cancer? A population-based study

    PubMed Central

    Hall, S.F.; Griffiths, R.

    2016-01-01

    Background For oncologists and for patients, no site-specific clinical trial evidence has emerged for the use of concurrent chemotherapy with radiotherapy (ccrt) over radiotherapy (rt) alone for cancer of the hypopharynx (hpc) or for other human papilloma virus–negative head-and-neck cancers. Methods This retrospective population-based cohort study using administrative data compared treatments over time (1990–2000 vs. 2000–2010), treatment outcomes, and outcomes over time in 1333 cases of hpc diagnosed in Ontario between January 1990 and December 2010. Results The incidence of hpc is declining; the use of ccrt that began in 2001 is increasing; and the 3-year overall survival for all patients remains poor at 34.6%. No difference in overall survival was observed in a comparison of patients treated in the decade before ccrt and of patients treated in the decade during the uptake of ccrt. Conclusions The addition of ccrt to the armamentarium of treatment options for oncologists treating head-and-neck patients did not improve outcomes for hpc at the population level. PMID:27536177

  3. Study of stability and thermodynamic properties of water-in-diesel nanoemulsion fuels with nano-Al additive

    NASA Astrophysics Data System (ADS)

    Mehta, Rakhi N.; More, Utkarsh; Malek, Naved; Chakraborty, Mousumi; Parikh, Parimal A.

    2015-11-01

    The present work addresses the formation of water-in-diesel (W/D) nanoemulsion by blending different percentages of water along with nano-Al additive in various propositions to enhance the combustion characteristics. The roles of various surfactants such as Sorbitan monooleate (Span 80), Triton X-100, Tetradecyltrimethylammonium bromide, and newly synthesized and characterized dicationic surfactants were discussed based upon their ability to stabilize the nanoemulsions. Surface active properties of the surfactants were determined by measuring their interfacial tension and subsequently by measuring the critical micelle concentration of the surfactants. Triton X-100 was found to be the most efficient surfactant for the current water-in-diesel nanoemulsion as it stabilized the suspensions for more than 8 h. Particle size analysis proved emulsion size to be in the order of nanometer, and zeta potential values were found to have neutral behavior at water-diesel interface. Experimental studies confirmed that that blends W/D [1 % (vol.) water] and W/DA [1 % (vol.) water, 0.1 % (wt.) nano-Al] were thermodynamically stable.

  4. A five-year study of the impact of nitrogen addition on methane uptake in alpine grassland

    PubMed Central

    Yue, Ping; Li, Kaihui; Gong, Yanming; Hu, Yukun; Mohammat, Anwar; Christie, Peter; Liu, Xuejun

    2016-01-01

    It remains unclear how nitrogen (N) deposition affects soil methane (CH4) uptake in semiarid and arid zones. An in situ field experiment was conducted from 2010 to 2014 to systematically study the effect of various N application rates (0, 10, 30, and 90 kg N ha−1 yr−1) on CH4 flux in alpine grassland in the Tianshan Mountains. No significant influence of N addition on CH4 uptake was found. Initially the CH4 uptake rate increased with increasing N application rate by up to 11.5% in 2011 and then there was gradual inhibition by 2014. However, the between-year variability in CH4 uptake was very highly significant with average uptake ranging from 52.9 to 106.6 μg C m−2 h−1 and the rate depended largely on seasonal variability in precipitation and temperature. CH4 uptake was positively correlated with soil temperature, air temperature and to a lesser extent with precipitation, and was negatively correlated with soil moisture and NO3−-N content. The results indicate that between-year variability in CH4 uptake was impacted by precipitation and temperature and was not sensitive to elevated N deposition in alpine grassland. PMID:27571892

  5. Addition of home-based cognitive retraining to treatment as usual in first episode schizophrenia patients: A randomized controlled study

    PubMed Central

    Hegde, Shantala; Rao, Shobini L.; Raguram, Ahalya; Gangadhar, Bangalore N.

    2012-01-01

    Objective: We examined the effectiveness of a 2-month-long home-based cognitive retraining program together with treatment as usual (TAU; psychoeducation and drug therapy) on neuropsychological functions, psychopathology, and global functioning in patients with first episode schizophrenia (FES) as well as on psychological health and perception of level of family distress in their caregivers. Materials and Methods: Forty-five FES patients were randomly assigned to either treatment group receiving home-based cognitive retraining along with TAU (n=22) or to control group receiving TAU alone (n=23). Patients and caregivers received psychoeducation. Patients and one of their caregivers were assessed for the above parameters at baseline, post-assessment (2 months) and at 6-months follow-up assessment. Results: Of the 45 patients recruited, 12 in the treatment group and 11 in the control group completed post-intervention and follow-up assessments. Addition of home-based cognitive retraining along with TAU led to significant improvement in neuropsychological functions of divided attention, concept formation and set-shifting ability, and planning. Effect sizes were large, although the sample size was small. Conclusions: Home-based cognitive retraining program has shown promise. However, further studies examining this program on a larger cohort with rigorous design involving independent raters are suggested. PMID:22556432

  6. A five-year study of the impact of nitrogen addition on methane uptake in alpine grassland.

    PubMed

    Yue, Ping; Li, Kaihui; Gong, Yanming; Hu, Yukun; Mohammat, Anwar; Christie, Peter; Liu, Xuejun

    2016-01-01

    It remains unclear how nitrogen (N) deposition affects soil methane (CH4) uptake in semiarid and arid zones. An in situ field experiment was conducted from 2010 to 2014 to systematically study the effect of various N application rates (0, 10, 30, and 90 kg N ha(-1) yr(-1)) on CH4 flux in alpine grassland in the Tianshan Mountains. No significant influence of N addition on CH4 uptake was found. Initially the CH4 uptake rate increased with increasing N application rate by up to 11.5% in 2011 and then there was gradual inhibition by 2014. However, the between-year variability in CH4 uptake was very highly significant with average uptake ranging from 52.9 to 106.6 μg C m(-2) h(-1) and the rate depended largely on seasonal variability in precipitation and temperature. CH4 uptake was positively correlated with soil temperature, air temperature and to a lesser extent with precipitation, and was negatively correlated with soil moisture and NO3(-)-N content. The results indicate that between-year variability in CH4 uptake was impacted by precipitation and temperature and was not sensitive to elevated N deposition in alpine grassland. PMID:27571892

  7. Dual-Mission Large Aircraft Feasibility Study and Aerodynamic Investigation

    NASA Technical Reports Server (NTRS)

    Mavris, Dimitri

    1997-01-01

    A Dual-Mission Large Aircraft, or DMLA, represents the possibility of a single aircraft capable of fulfilling both a Global Reach Aircraft (GRA) and Very Large Transport (VLT) roles. The DMLA, by combining the GRA and VLT into a single new aircraft, could possibly lower the aircraft manufacturer's production costs through the resulting increase in production quantity. This translates into lower aircraft acquisition costs, a primary concern for both the Air Force and commercial airlines. This report outlines the first steps taken in this study, namely the assessment of technical and economic feasibility of the DMLA concept. In the course of this project, specialized GRA and VLT aircraft were sized for their respective missions, using baseline conventional (i.e., lacking advanced enabling technologies) aircraft models from previous work for the Air Force's Wright Laboratory and NASA-Langley. DMLA baseline aircraft were then also developed, by first sizing the aircraft for the more critical of the two missions and then analyzing the aircraft's performance over the other mission. The resulting aircraft performance values were then compared to assess technical feasibility. Finally, the life-cycle costs of each aircraft (GRA, VLT, and DMLA) were analyzed to quantify economic feasibility. These steps were applied to both a two-engine aircraft set, and a four-engine aircraft set.

  8. Apheresis and intravenous immunoglobulins used in addition to conventional therapy to treat high-risk pregnant antiphospholipid antibody syndrome patients. A prospective study.

    PubMed

    Ruffatti, Amelia; Favaro, Maria; Hoxha, Ariela; Zambon, Alessandra; Marson, Piero; Del Ross, Teresa; Calligaro, Antonia; Tonello, Marta; Nardelli, Giovanni B

    2016-06-01

    Pregnant women with triple antibody positive antiphospholipid syndrome (APS) who have had thrombosis or a history of early, severe pregnancy complications are generally considered at high risk of pregnancy loss. The objectives of this study were to investigate the efficacy and safety of a relatively new treatment protocol used in addition to conventional therapy in high-risk pregnant patients affected with primary APS. The study's two inclusion criteria were: (1) the presence of triple antiphospholipid positivity, (2) previous thrombosis and/or a history of one or more early, severe pregnancy complications. Eighteen pregnancies occurring between 2002 and 2015 in 14 APS patients, (mean age 34.8±3.6 SD) were monitored. All 14 (100%) patients had triple antiphospholipid positivity. In addition, six of them (42.8%) had a history of thrombosis, four (28.6%) had one or more previous early and severe pregnancy complications, and four (30.8%) met both clinical study criteria. The study protocol included weekly plasmapheresis or immunoadsorption and fortnightly 1g/kg intravenous immunoglobulins. Seventeen of the pregnancies (94.4%) produced live neonates, all born between the 26th and 37th weeks of gestation (mean 33.1±3.5 SD). One female (5.5%), born prematurely at 24 weeks, died of sepsis a week after birth. There were two cases (11.1%) of severe pregnancy complications. No treatment side effects were registered. Given the high live birth rate and the safety associated to it, the study protocol described here could be taken into consideration by medical teams treating high-risk APS pregnant patients. PMID:27088752

  9. Seniors Falls Investigative Methodology (SFIM): A Systems Approach to the Study of Falls in Seniors

    ERIC Educational Resources Information Center

    Zecevic, Aleksandra A.; Salmoni, Alan W.; Lewko, John H.; Vandervoort, Anthony A.

    2007-01-01

    An in-depth understanding of human factors and human error is lacking in current research on seniors' falls. Additional knowledge is needed to understand why seniors are falling. The purpose of this article is to describe the adapting of the Integrated Safety Investigation Methodology (ISIM) (used for investigating transportation and industrial…

  10. The guanidine and benzoic acid (1:1) complex. The polarized vibrational studies and theoretical investigations

    NASA Astrophysics Data System (ADS)

    Drozd, M.; Dudzic, D.

    2015-03-01

    The structure of guanidinium benzoate was discovered by Silva et al. On the basis of these X-ray crystallographic studies the detailed DFT investigation are performed. According to this result the infrared spectrum for one theoretical molecule was calculated. On the basis of potential energy distribution (PED) analysis the clear-cut assignments of observed bands were performed. For the calculated molecule with energy minimum the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) were obtained. The energy difference between HOMO and LUMO was analyzed. According to theoretical calculations the direction of dipole moments (TDM) for bands observed in infrared spectra are analyzed. Verification of theoretical TDM behaviors is performed on the basis of experimental polarized specular reflection infrared spectra. The detailed assignments of observed bands is presented. Both theoretical and experimental spectra are compared. Crucial role of three different hydrogen bonds is studied in detail. Additionally, on the basis of differential scanning calorimetric study no phase transition was found in investigated crystal in the range 100-400 K.

  11. Column studies on transport of deicing additive benzotriazole in a sandy aquifer and a zerovalent iron barrier.

    PubMed

    Jia, Yu; Breedveld, Gijs D; Aagaard, Per

    2007-11-01

    Benzotriazole (BTA), a chemical with wide industrial applications, is a typical additive in deicer/anti-icer used at airport. To achieve a better understanding of the transport behaviour and environmental fate of BTA, laboratory column studies have been performed on subsoil samples from Oslo Airport, Gardermoen. To explore possibilities for aquifer remediation, BTA behaviour was also studied in a column of granular zerovalent iron (Fe(0)). The subsoil column study demonstrates a very limited retardation of BTA. Consecutive loadings of BTA of the subsoil column showed no change of the break-through curve (BTC) and complete desorption was observed. The sorption behaviour of BTA to metallic iron (Fe(0)) was rather complex. Considerable retardation was observed in the Fe(0) column and repeated BTA loading resulted in an earlier break-through. Between 20% and 50% of the input concentration was retained permanently in the iron (Fe(0)) column. The BTA sorption to metallic iron was found to be enhanced by chloride which lowered the break-through concentration (i.e the C/C(0) plateau). The fraction of BTA remaining in the iron column was found to vary with the flow rate, indicating a time dependant multilayer sorption mechanism. The steady increase in the amount of adsorbed BTA to the iron column during loading corresponds to a rather strong bonding of 4-15 BTA layers to the iron surface. A very slow desorption of BTA was observed; even after flushing with 753 pore volumes of BTA free water, 7.5% of the BTA remained in the column. A geochemical model was developed based on PHREEQC-2 to simulate the sorption and transport of BTA in the tested materials. The BTA sorption was modelled with Freundlich sorption isotherms, as earlier determined in batch experiments. A slight adjustment of the Freundlich parameters was required to fit the observed column break-through. However, our model was not able to simulate the long-term retainment of BTA in the granular iron columns. The

  12. Towards a phylogenetic generic classification of Thelypteridaceae: Additional sampling suggests alterations of neotropical taxa and further study of paleotropical genera.

    PubMed

    Almeida, Thaís Elias; Hennequin, Sabine; Schneider, Harald; Smith, Alan R; Batista, João Aguiar Nogueira; Ramalho, Aline Joseph; Proite, Karina; Salino, Alexandre

    2016-01-01

    Thelypteridaceae is one of the largest fern families, having about 950 species and a cosmopolitan distribution but with most species occurring in tropical and subtropical regions. Its generic classification remains controversial, with different authors recognizing from one up to 32 genera. Phylogenetic relationships within the family have not been exhaustively studied, but previous studies have confirmed the monophyly of the lineage. Thus far, sampling has been inadequate for establishing a robust hypothesis of infrafamilial relationships within the family. In order to understand phylogenetic relationships within Thelypteridaceae and thus to improve generic reclassification, we expand the molecular sampling, including new samples of Old World taxa and, especially, many additional neotropical representatives. We also explore the monophyly of exclusively or mostly neotropical genera Amauropelta, Goniopteris, Meniscium, and Steiropteris. Our sampling includes 68 taxa and 134 newly generated sequences from two plastid genomic regions (rps4-trnS and trnL-trnF), plus 73 rps4 and 72 trnL-trnF sequences from GenBank. These data resulted in a concatenated matrix of 1980 molecular characters for 149 taxa. The combined data set was analyzed using maximum parsimony and bayesian inference of phylogeny. Our results are consistent with the general topological structure found in previous studies, including two main lineages within the family: phegopteroid and thelypteroid. The thelypteroid lineage comprises two clades; one of these included the segregates Metathelypteris, Coryphopteris, and Amauropelta (including part of Parathelypteris), whereas the other comprises all segregates of Cyclosorus s.l., such as Goniopteris, Meniscium, and Steiropteris (including Thelypteris polypodioides, previously incertae sedis). The three mainly neotropical segregates were found to be monophyletic but nested in a broadly defined Cyclosorus. The fourth mainly neotropical segregate, Amauropelta

  13. Formation pathways of DMSO(2) in the addition channel of the OH-initiated DMS oxidation: A theoretical study.

    PubMed

    Ramírez-Anguita, Juan M; González-Lafont, Angels; Lluch, José M

    2009-07-15

    The production of dimethyl sulfoxide (DMSO) and dimethyl sulfone (DMSO(2)) in the dimethyl sulfide (DMS) degradation scheme initiated by the hydroxyl (OH) radical has been shown to be very sensitive to nitrogen oxides (NO(x)) levels. In the present work we have explored the potential energy surfaces corresponding to several reaction pathways which yield DMSO(2) from the CH(3)S(O)(OH)CH(3) adduct [including the formation of CH(3)S(O)(OH)CH(3) from the reaction of DMSO with OH] and the reaction channels that yield DMSO or/and DMSO(2) from the CH(3)S(O(2))(OH)CH(3) adduct are also studied. The formation of the CH(3)S(O(2))(OH)CH(3) adduct from CH(3)S(OH)CH(3) (DMS-OH) and O(2) was analyzed in our previous work. All these pathways due to the presence of NO(x) (NO and NO(2)) and also due to the reactions with O(2), OH and HO(2) are compared with the objective of inferring their kinetic relevance in the laboratory experiments that measure DMSO(2) (and DMSO) formation yields. In particular, our theoretical results clearly show the existence of NO(x)-dependent pathways leading to the formation of DMSO(2), which could explain some of these experimental results in comparison with experimental measurements carried out in NO(x)-free conditions. Our results indicate that the relative importance of the addition channel in the DMS oxidation process can be dependent on the NO(x) content of chamber experiments and of atmospheric conditions. PMID:19072765

  14. Addition of straw or sawdust to mitigate greenhouse gas emissions from slurry produced by housed cattle: a field incubation study.

    PubMed

    van der Weerden, Tony J; Luo, Jiafa; Dexter, Moira

    2014-07-01

    The use of housed wintering systems (e.g., barns) associated with dairy cattle farming is increasing in southern New Zealand. Typically, these wintering systems use straw or a woodmix as bedding material. Ammonia (NH) and greenhouse gas (GHG) emissions (nitrous oxide [NO] and methane [CH]) associated with storage of slurry + bedding material from wintering systems is poorly understood. A field incubation study was conducted to determine such emissions from stored slurry where bedding material (straw and sawdust) was added at two rates and stored for 7 mo. During the first 4 mo of storage, compared with untreated slurry, the addition of sawdust significantly reduced NH and CH emissions from 29 to 3% of the initial slurry nitrogen (N) content and from 0.5 to <0.01% of the initial slurry carbon (C) content. However, sawdust enhanced NO emissions to 0.7% of the initial slurry-N content, compared with <0.01% for untreated slurry. Straw generally had an intermediate effect. Extending the storage period to 7 mo increased emissions from all treatments. Ammonia emissions were inversely related to the slurry C:N ratio and total solid (TS) content, and CH emissions were inversely related to slurry TS content. Mitigation of GHG emissions from stored slurry can be achieved by reducing the storage period as much as possible after winter slurry collection, providing ground conditions allow access for land spreading and nutrient inputs match pasture requirements. Although adding bedding material can reduce GHG emissions during storage, increased manure volumes for carting and spreading need to be considered. PMID:25603082

  15. Effects of Additives and Impurity on the Adhesive Behavior of the NiAl(110)/Al2O3 (0001) Interface: An Ab Initio Study

    NASA Astrophysics Data System (ADS)

    Ozfidan, Isil; Chen, Kuiying; Fu, Ming

    2011-12-01

    Using ab initio density functional theory (DFT), the adhesive behavior of NiAl(110)/Al2O3(0001) interface in thermal barrier coatings was systematically studied with an emphasis on the effects of alloying additives and impurity elements. To reveal possible atomic-scale mechanisms, the separations between certain atoms at the interface, the electron localization function (ELF), and the electron density of states (DOS) are thoroughly investigated. First, effects of individual elements such as S, Pt, and Cr, and reactive elements (REs) Hf, Zr, and Y, on the work of separation, W sep, of the interface were examined. As expected, the segregation of S to the interface significantly degrades the adhesion, while the substitution of Pt for Ni adjacent to the interface does not enhance the W sep. Cr and RE addition to the interface individually result in a considerable increase of W sep. Second, the addition of Pt, Hf, and Cr to the S containing interface is shown to mitigate the detrimental effect of sulfur to some extent. Co doping the interface with a selected combination of (Pt, Hf), (Pt, Cr), (Cr, Hf), (Cr, Y), (Hf, Y), and (Y, Zr) was implemented to probe possible synergistic interactions between elements on W sep. Synergistic effects are detected on increasing W sep for (Hf, Y), (Hf, Zr) combinations. Co doping the interface with (Cr, Y) and (Cr, Hf), however, is found to weaken the adhesion. Through a detailed analysis of electronic structures in terms of ELF and DOS, four dominant bonds across the interface, RE-O, RE-Ni, Aloxide-Ni, and AlNiAl-O, are identified to play a decisive role in governing the adhesive strength of the interface.

  16. PILOT-SCALE STUDIES ON THE EFFECT OF BROMINE ADDITION ON THE EMISSIONS OF CHLORINATED ORGANIC COMBUSTION BY-PRODUCTS

    EPA Science Inventory

    The addition of brominated organic compounds to the feed of a pilot-scale incinerator burning chlorinated waste has been found previously, under some circumstances, to enhance emissions of volatile and semivolatile organic chlorinated products of incomplete combustion (PiCs) incl...

  17. Cultural Dimensions of Feedback at an Australian University: A Study of International Students with English as an Additional Language

    ERIC Educational Resources Information Center

    Warner, Richard; Miller, Julia

    2015-01-01

    International students with English as an additional language face transitional challenges when entering a new academic culture. One such challenge involves optimising feedback to help foster their academic development, bearing in mind that feedback is not a culturally neutral entity (Nazif, A., Biswas, D., & Hilbig, R. (2004-2005). Towards an…

  18. Metabolic studies of the Amaryllidaceous alkaloids galantamine and lycorine based on electrochemical simulation in addition to in vivo and in vitro models.

    PubMed

    Jahn, Sandra; Seiwert, Bettina; Kretzing, Sascha; Abraham, Getu; Regenthal, Ralf; Karst, Uwe

    2012-12-01

    Alkaloids from the plant family of Amaryllidaceae, such as galantamine (GAL) and lycorine (LYC), are known to exhibit numerous promising biological and pharmacological activities like antibacterial, antiviral or anti-inflammatory effects. Nonetheless, studies on the biotransformation pathway are rare for this substance class, unless approval for use as medication exists. While GAL has become a prescription drug used to alleviate and delay the symptoms of Alzheimer's disease, LYC exhibits potential antitumor properties. However, it has also been linked to toxic effects resulting in nausea and emesis. Whereas there are few publications available describing the metabolic pathway of GAL in animals and humans, the metabolism of LYC is unknown. Therefore, this study is concerned with the investigation of the oxidative metabolism of GAL and LYC, which was achieved by means of three different approaches: electrochemical (EC) simulation coupled on-line to liquid chromatography (LC) with electrospray mass spectrometric (ESI-MS) detection was applied in addition to in vivo experiments in beagle dog analyzing plasma (BP) and in vitro incubations with rat liver microsomes (RLM). This way, it should be investigated if electrochemistry can be used to predict the oxidative metabolism of alkaloids. For GAL, the EC model was capable of predicting most metabolites observed during microsomal and plasma studies, including N-demethylated, dehydrogenated and oxygenated products or a combination of these. LYC was found to be metabolized far less than GAL in the animal-based approaches, but several EC oxidation products were generated. Some principal metabolic routes could successfully be correlated for this alkaloid as well, comprising dehydrogenation, dehydration to ungeremine and oxygenation reactions. PMID:23176740

  19. Physiological and Proteomic Investigations to Study the Response of Tomato Graft Unions under Temperature Stress

    PubMed Central

    Muneer, Sowbiya; Ko, Chung Ho; Wei, Hao; Chen, Yuze; Jeong, Byoung Ryong

    2016-01-01

    Background Grafting is an established practice for asexual propagation in horticultural and agricultural crops. The study on graft unions has become of interest for horticulturists using proteomic and genomic techniques to observe transfer of genetic material and signal transduction pathways from root to shoot and shoot to root. Another reason to study the graft unions was potentially to observe resistance against abiotic stresses. Using physiological and proteomic analyses, we investigated graft unions (rootstock and scions) of tomato genotypes exposed to standard-normal (23/23 and 25/18°C day/night) and high-low temperatures (30/15°C day/night). Results Graft unions had varied responses to the diverse temperatures. High-low temperature, but not standard-normal temperature, induced the production of reactive oxygen species (ROS) in the form of H2O2 and O2-1 in rootstock and scions. However, the expression of many cell protection molecules was also induced, including antioxidant enzymes and their immunoblots, which also show an increase in their activities such as superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX). The graft interfaces thus actively defend against stress by modifying their physiological and proteomic responses to establish a new cellular homeostasis. As a result, many proteins for cellular defense were regulated in graft unions under diverse temperature, in addition to the regulation of photosynthetic proteins, ion binding/transport proteins, and protein synthesis. Moreover, biomass, hardness, and vascular transport activity were evaluated to investigate the basic connectivity between rootstock and scions. Conclusions Our study provides physiological evidence of the grafted plants’ response to diverse temperature. Most notably, our study provides novel insight into the mechanisms used to adapt the diverse temperature in graft unions (rootstock/scion). PMID:27310261

  20. An efficacy study on improving balance and gait in subacute stroke patients by balance training with additional motor imagery: a pilot study

    PubMed Central

    Bae, Young-Hyeon; Ko, YoungJun; Ha, HyunGeun; Ahn, So Yeon; Lee, WanHee; Lee, Suk Min

    2015-01-01

    [Purpose] The few studies conducted on subacute stroke patients have focused only on gait function improvement. This study therefore aimed to confirm the effect of balance training with additional motor imagery on balance and gait improvement in subacute stroke patients. [Subjects and Methods] Participants were divided into an experimental or control group. The experimental group received balance training for 20 minutes/day with mental imagery for 10 minutes/day, three days/week, for four weeks. The control group received only balance training for 30 minutes. Before and after the 12 sessions, balance and gait ability were assessed by the researcher and a physical therapist. [Results] After completion of the 4-week intervention, Berg Balance Scale, Timed Up and Go test, Functional Reach Test, and Four Square Step test scores significantly increased in the experimental group. In the control group, Berg Balance Scale and Functional Reach Test scores significantly improved. Changes in the Timed Up and Go test, Functional Reach Test, and Four Square Step Test scores after intervention were significantly higher in the experimental than in the control group. [Conclusion] Specific balance training with additional motor imagery may result in better rehabilitation outcomes of gait and balance ability than balance training alone. PMID:26644684

  1. Vildagliptin in addition to metformin improves retinal blood flow and erythrocyte deformability in patients with type 2 diabetes mellitus – results from an exploratory study

    PubMed Central

    2013-01-01

    Numerous rheological and microvascular alterations characterize the vascular pathology in patients with type 2 diabetes mellitus (T2DM). This study investigated effects of vildagliptin in comparison to glimepiride on retinal microvascular blood flow and erythrocyte deformability in T2DM. Fourty-four patients with T2DM on metformin monotherapy were included in this randomized, exploratory study over 24 weeks. Patients were randomized to receive either vildagliptin (50 mg twice daily) or glimepiride individually titrated up to 4 mg in addition to ongoing metformin treatment. Retinal microvascular blood flow (RBF) and the arteriolar wall to lumen ratio (WLR) were assessed using a laser doppler scanner. In addition, the erythrocyte elongation index (EI) was measured at different shear stresses using laserdiffractoscopy. Both treatments improved glycaemic control (p < 0.05 vs. baseline; respectively). While only slight changes in RBF and the WLR could be observed during treatment with glimepiride, vildagliptin significantly increased retinal blood flow and decreased the arterial WLR (p < 0.05 vs. baseline respectively). The EI increased during both treatments over a wide range of applied shear stresses (p < 0.05 vs. baseline). An inverse correlation could be observed between improved glycaemic control (HbA1c) and EI (r = −0.524; p < 0.0001) but not with the changes in retinal microvascular measurements. Our results suggest that vildagliptin might exert beneficial effects on retinal microvascular blood flow beyond glucose control. In contrast, the improvement in erythrocyte deformability observed in both treatment groups, seems to be a correlate of improved glycaemic control. PMID:23565740

  2. Segmentation and additive approach: A reliable technique to study noncovalent interactions of large molecules at the surface of single-wall carbon nanotubes.

    PubMed

    Torres, Ana M; Scheiner, Steve; Roy, Ajit K; Garay-Tapia, Andrés M; Bustamante, John; Kar, Tapas

    2016-08-01

    This investigation explores a new protocol, named Segmentation and Additive approach (SAA), to study exohedral noncovalent functionalization of single-walled carbon nanotubes with large molecules, such as polymers and biomolecules, by segmenting the entire system into smaller units to reduce computational cost. A key criterion of the segmentation process is the preservation of the molecular structure responsible for stabilization of the entire system in smaller segments. Noncovalent interaction of linoleic acid (LA, C18 H32 O2 ), a fatty acid, at the surface of a (10,0) zigzag nanotube is considered for test purposes. Three smaller segmented models have been created from the full (10,0)-LA system and interaction energies were calculated for these models and compared with the full system at different levels of theory, namely ωB97XD, LDA. The success of this SAA is confirmed as the sum of the interaction energies is in very good agreement with the total interaction energy. Besides reducing computational cost, another merit of SAA is an estimation of the contributions from different sections of the large system to the total interaction energy which can be studied in-depth using a higher level of theory to estimate several properties of each segment. On the negative side, bulk properties, such as HOMO-LUMO (highest occupied molecular orbital - lowest occupied molecular orbital) gap, of the entire system cannot be estimated by adding results from segment models. © 2016 Wiley Periodicals, Inc. PMID:27241227

  3. A Meta-Analysis of Cross Sectional Studies Investigating Language in Maltreated Children

    ERIC Educational Resources Information Center

    Lum, Jarrad A. G.; Powell, Martine; Timms, Lydia; Snow, Pamela

    2015-01-01

    Purpose: In this review article, meta-analysis was used to summarize research investigating language skills in maltreated children. Method: A systematic search of published studies was undertaken. Studies were included in the meta-analysis if they investigated language skills in groups comprising maltreated and nonmaltreated children. Studies were…

  4. Hanford waste-form release and sediment interaction: A status report with rationale and recommendations for additional studies

    SciTech Connect

    Serne, R.J. ); Wood, M.I. )

    1990-05-01

    This report documents the currently available geochemical data base for release and retardation for actual Hanford Site materials (wastes and/or sediments). The report also recommends specific laboratory tests and presents the rationale for the recommendations. The purpose of this document is threefold: to summarize currently available information, to provide a strategy for generating additional data, and to provide recommendations on specific data collection methods and tests matrices. This report outlines a data collection approach that relies on feedback from performance analyses to ascertain when adequate data have been collected. The data collection scheme emphasizes laboratory testing based on empiricism. 196 refs., 4 figs., 36 tabs.

  5. Effect of additives on distributions of lamellar structures in sheared polymer: a study of synchrotron small-angle x-ray scattering

    NASA Astrophysics Data System (ADS)

    Zhu, Peng-Wei; Edward, Graham; Nichols, Lance

    2009-12-01

    The effects of additives on the distributions of lamellar morphology and orientation in sheared isotactic polypropylene were investigated using the small beam of synchrotron small-angle x-ray scattering. The Cu-phthalocyanine can template the lamellar orientation even under low shear rates, whereas the ultramarine blue cannot. The surface contact is suggested to play a role in stabilizing the formation of oriented nuclei which subsequently direct the growth of oriented lamellae. The additives have no notable effects on the long spacing in the shear region. However, at high shear rates, they decrease the thickness of crystalline lamellae or increase the thickness of amorphous lamellae. Since the additives increase the degree of volume crystalline in the shear region, the number of crystalline lamellae should be increased. The results are helpful in designing and selecting suitable additives for controlling lamellar morphology and orientation.

  6. Evaluation of effect of addition of 2% chlorhexidine on the sealing ability of Biodentine: An in vitro study

    PubMed Central

    Suri, Navleen Kaur; Nikhil, Vineeta; Jha, Padmanabh; Jaiswal, Shikha

    2015-01-01

    Aim: To evaluate the effect of the addition of 2% chlorhexidine on the sealing ability of Biodentine. Materials and Methods: Forty-six extracted human premolar teeth with single canal and apical foramen were selected, cleaned, and decoronated to standardize the length of 17 mm. Canals were prepared using ProTaper rotary files till size F4. The samples were divided into 2 experimental groups of 20 samples each on the basis of absence/presence of 2% chlorhexidine in liquid: Group BM = Biodentine mixed with the provided liquid, Group BC = Biodentine mixed with 2% chlorhexidine in provided liquid. Three samples, each were assigned to control groups: Group BP (positive control) = No root end filling was placed, Group BN (negative control) = Root ends were filled as in Group BM, and entire external surface was coated with sticky wax. The samples were then evaluated for the apical sealing using fluid filtration method. Results: Results were analyzed using Student's t-test (P ≤ 0.05). Group BC showed the better sealing ability (3.06) as compared to Group BM (3.85). However, the difference was statistically insignificant (P > 0.05). Conclusion: Addition of 2% chlorhexidine to the liquid enhanced the sealing ability of Biodentine. PMID:26752844

  7. A feasibility study regarding the addition of a fifth control to a rotorcraft in-flight simulator

    NASA Technical Reports Server (NTRS)

    Turner, Simon; Andrisani, Dominick, II

    1992-01-01

    The addition of a large movable horizontal tail surface to the control system of a rotorcraft in-flight simulator being developed from a Sikorsky UH-60A Black Hawk Helicopter is evaluated. The capabilities of the control surface as a trim control and as an active control are explored. The helicopter dynamics are modeled using the Generic Helicopter simulation program developed by Sikorsky Aircraft. The effect of the horizontal tail on the helicopter trim envelope is examined by plotting trim maps of the aircraft attitude and controls as a function of the flight speed and horizontal tail incidence. The control power of the tail surface relative to that of the other controls is examined by comparing control derivatives extracted from the simulation program over the flight speed envelope. The horizontal tail's contribution as an active control is evaluated using an explicit model following control synthesis involving a linear model of the helicopter in steady, level flight at a flight speed of eighty knots. The horizontal tail is found to provide additional control flexibility in the longitudinal axis. As a trim control, it provides effective control of the trim pitch attitude at mid to high forward speeds. As an active control, the horizontal tail provides useful pitching moment generating capabilities at mid to high forward speeds.

  8. Green algal over cyanobacterial dominance promoted with nitrogen and phosphorus additions in a mesocosm study at Lake Taihu, China.

    PubMed

    Ma, Jianrong; Qin, Boqiang; Paerl, Hans W; Brookes, Justin D; Wu, Pan; Zhou, Jian; Deng, Jianming; Guo, Jinsong; Li, Zhe

    2015-04-01

    Enrichment of waterways with nitrogen (N) and phosphorus (P) has accelerated eutrophication and promoted cyanobacterial blooms worldwide. An understanding of whether cyanobacteria maintain their dominance under accelerated eutrophication will help predict trends and provide rational control measures. A mesocosm experiment was conducted under natural light and temperature conditions in Lake Taihu, China. It revealed that only N added to lake water promoted growth of colonial and filamentous cyanobacteria (Microcystis, Pseudoanabaena and Planktothrix) and single-cell green algae (Cosmarium, Chlorella, and Scenedesmus). Adding P alone promoted neither cyanobacteria nor green algae significantly. N plus P additions promoted cyanobacteria and green algae growth greatly. The higher growth rates of green algae vs. cyanobacteria in N plus P additions resulted in the biomass of green algae exceeding that of cyanobacteria. This indicates that further enrichment with N plus P in eutrophic water will enhance green algae over cyanobacterial dominance. However, it does not mean that eutrophication problems will cease. On the contrary, the risk will increase due to increasing total phytoplankton biomass. PMID:25516247

  9. Study of the effects of potassium addition to supported iron catalysts in the Fischer-Tropsch reaction

    SciTech Connect

    Miller, D.G.; Moskovits, M.

    1988-10-20

    The Fischer-Tropsch activity of supported iron catalysts prepared via electrochemical techniques has been evaluated as a function of potassium addition. Catalyst pretreatment in 0.09, 0.18, and 0.27 M K/sub 2/CO/sub 3/ solutions generated potassium levels of 1.7, 2.8, and 3.9 wt %, respectively. Pretreatment in 0.18 M KOH provided a catalyst with 2.3 wt% potassium and facilitated comparison of the effects of the basicity of the pretreatment solution upon catalyst activity. A maximum in catalyst activity and CO conversion was noted upon increasing K content, followed by a sharp decline in activity at potassium levels in excess of the maximum. The hydrogenation ability of the catalyst decreased, and a shift to higher molecular weight products was observed, with increasing potassium content. The type of pretreatment solution had little effect on the catalyst activity or the product selectivity.

  10. Meta-analysis of high-latitude nitrogen-addition and warming studies implies ecological mechanisms overlooked by land models

    DOE PAGESBeta

    Bouskill, N. J.; Riley, W. J.; Tang, J. Y.

    2014-12-11

    Accurate representation of ecosystem processes in land models is crucial for reducing predictive uncertainty in energy and greenhouse gas feedbacks with the climate. Here we describe an observational and modeling meta-analysis approach to benchmark land models, and apply the method to the land model CLM4.5 with two versions of belowground biogeochemistry. We focused our analysis on the aboveground and belowground responses to warming and nitrogen addition in high-latitude ecosystems, and identified absent or poorly parameterized mechanisms in CLM4.5. While the two model versions predicted similar soil carbon stock trajectories following both warming and nitrogen addition, other predicted variables (e.g., belowgroundmore » respiration) differed from observations in both magnitude and direction, indicating that CLM4.5 has inadequate underlying mechanisms for representing high-latitude ecosystems. On the basis of observational synthesis, we attribute the model–observation differences to missing representations of microbial dynamics, aboveground and belowground coupling, and nutrient cycling, and we use the observational meta-analysis to discuss potential approaches to improving the current models. However, we also urge caution concerning the selection of data sets and experiments for meta-analysis. For example, the concentrations of nitrogen applied in the synthesized field experiments (average = 72 kg ha-1 yr-1) are many times higher than projected soil nitrogen concentrations (from nitrogen deposition and release during mineralization), which precludes a rigorous evaluation of the model responses to likely nitrogen perturbations. Overall, we demonstrate that elucidating ecological mechanisms via meta-analysis can identify deficiencies in ecosystem models and empirical experiments.« less

  11. Understanding the investigators: a qualitative study investigating the barriers and enablers to the implementation of local investigator-initiated clinical trials in Ethiopia

    PubMed Central

    Franzen, Samuel R P; Chandler, Clare; Enquselassie, Fikre; Siribaddana, Sisira; Atashili, Julius; Angus, Brian; Lang, Trudie

    2013-01-01

    Objectives Clinical trials provide ‘gold standard’ evidence for policy, but insufficient locally relevant trials are conducted in low-income and middle-income countries. Local investigator-initiated trials could generate highly relevant data for national governments, but information is lacking on how to facilitate them. We aimed to identify barriers and enablers to investigator-initiated trials in Ethiopia to inform and direct capacity strengthening initiatives. Design Exploratory, qualitative study comprising of in-depth interviews (n=7) and focus group discussions (n=3). Setting Fieldwork took place in Ethiopia during March 2011. Participants Local health researchers with previous experiences of clinical trials or stakeholders with an interest in trials were recruited through snowball sampling (n=20). Outcome measures Detailed discussion notes were analysed using thematic coding analysis and key themes were identified. Results All participants perceived investigator-initiated trials as important for generating local evidence. System and organisational barriers included: limited funding allocation, weak regulatory and administrative systems, few learning opportunities, limited human and material capacity and poor incentives for conducting research. Operational hurdles were symptomatic of these barriers. Lack of awareness, confidence and motivation to undertake trials were important individual barriers. Training, knowledge sharing and experience exchange were key enablers to trial conduct and collaboration was unanimously regarded as important for improving capacity. Conclusions Barriers to trial conduct were found at individual, operational, organisational and system levels. These findings indicate that to increase locally led trial conduct in Ethiopia, system wide changes are needed to create a more receptive and enabling research environment. Crucially, the creation of research networks between potential trial groups could provide much needed practical

  12. Study on visible-light-curable polycarprolactone and poly(ethylene glycol) diacrylate for LCD-projected maskless additive manufacturing system

    NASA Astrophysics Data System (ADS)

    Cheng, Yih-Lin; Kao, Hao-Lun

    2015-09-01

    Photopolymers have been applied in many Additive Manufacturing (AM) systems and mostly are cured by UV light. Biodegradable photo-curable polymers are very limited and are not commercially available. DLP-projected maskless AM systems become more and more popular nowadays, but its working area is limited if the part resolution is required. For larger working envelope purpose, liquid crystal display (LCD) panel has great potentials, and LCD's resolution has been improved significantly in the past few years due to the smart phone application. Therefore, in this research, LCD panel is used to replace DLP for a maskless AM system to cure biodegradable materials, Polycarprolactone (PCL) and Poly(ethylene glycol) diacrylate (PEG-DA). Due to the characteristics of LCD panel, the material systems should be sensitive and photo-polymerized in visible-light range, particularly in RGB. In this study, various percentages of visiblelight photoinitiator, Irgacure 784, in the material systems were investigated. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were utilized to characterize cured biomaterials. Because of the use of photoinitiator, the biocompatibility of the cured materials was also concerned, and hence, MTT assay tests were performed. The preliminary tests of fabrication, using the LCD-projected maskless AM system, cured grid patterns to illustrate the feasibility. The visible-light-curable PCL and PEG-DA will be able to be adopted in tissue engineering scaffold applications in the future.

  13. Remedial investigation/feasibility study badger army ammunition plant Baraboo, Wisconsin. Volume 2. Feasibility study report

    SciTech Connect

    1994-08-01

    This Feasibility Study (FS) report for the Badger Army Ammunition Plant (BAAP) in Baraboo, Wisconsin, was prepared by ABB Environmental Services, Inc. (ABB-ES) as a component of Task Order 1 of Contract DAAAl5-91-D-OOO8 with the U.S. Army Environmental Center (USAEC). This report uses the results presented in the Final Remedial Investigation (RI) report (ABB-ES, 1993a) to develop and screen alternatives for remediation of contaminated media at BAAP. The purpose of this FS report is to develop, screen, and evaluate site-specific remedial alternatives to mitigate the impact of site-derived chemicals and ultimately provide protection of human health and the environment. Preferred alternatives for each site are included in this report. Based on previous environmental studies at BAAP, 11 potential hazardous waste sites were ranked according to potential contributions of hazardous chemicals to the environment. These sites were designated as Waste Management Areas because some of the sites contain multiple Solid Waste Management Units (SWMUs). The sites selected to undergo facility assessment and corrective actions are: the Propellant Burning Ground (including Landfill), Deterrent Burning Ground, existing Landfill, Settling Ponds and Spoils Disposal Area, Rocket Paste Area, Oleum Plant and Oleum Plant Pond, Nitroglycerine Pond, old Acid Area, new Acid Area, and Ballistics Pond. The USAEC added an 11th site, the Old Fuel Oil Tank, to the list in October 1989 after discovery of fuel-contaminated soils during excavation of a water line in the vicinity of the old fuel oil tank foundation.

  14. Remedial investigation/feasibility study badger army ammunition plant Baraboo, Wisconsin. Volume 1. Feasibility study report

    SciTech Connect

    1994-08-01

    This Feasibility Study (FS) report for the Badger Army Ammunition Plant (BAAP) in Baraboo, Wisconsin, was prepared by ABB Environmental Services, Inc. (ABB-ES) as a component of Task Order 1 of Contract DAAAl5-91-D-OOO8 with the U.S. Army Environmental Center (USAEC). This report uses the results presented in the Final Remedial Investigation (RI) report (ABB-ES, 1993a) to develop and screen alternatives for remediation of contaminated media at BAAP. The purpose of this FS report is to develop, screen, and evaluate site-specific remedial alternatives to mitigate the impact of site-derived chemicals and ultimately provide protection of human health and the environment. Preferred alternatives for each site are included in this report. Based on previous environmental studies at BAAP, 11 potential hazardous waste sites were ranked according to potential contributions of hazardous chemicals to the environment. These sites were designated as Waste Management Areas because some of the sites contain multiple Solid Waste Management Units (SWMUs). The sites selected to undergo facility assessment and corrective actions are: the Propellant Burning Ground (including Landfill), Deterrent Burning Ground, existing Landfill, Settling Ponds and Spoils Disposal Area, Rocket Paste Area, Oleum Plant and Oleum Plant Pond, Nitroglycerine Pond, old Acid Area, new Acid Area, and Ballistics Pond. The USAEC added an 11th site, the Old Fuel Oil Tank, to the list in October 1989 after discovery of fuel-contaminated soils during excavation of a water line in the vicinity of the old fuel oil tank foundation.

  15. Activity of the Human Rhinovirus 3C Protease Studied in Various Buffers, Additives and Detergents Solutions for Recombinant Protein Production

    PubMed Central

    Tufail, Soban; Ismat, Fouzia; Imran, Muhammad; Iqbal, Mazhar; Mirza, Osman; Rhaman, Moazur

    2016-01-01

    Proteases are widely used to remove affinity and solubility tags from recombinant proteins to avoid potential interference of these tags with the structure and function of the fusion partner. In recent years, great interest has been seen in use of the human rhinovirus 3C protease owing to its stringent sequence specificity and enhanced activity. Like other proteases, activity of the human rhinovirus 3C protease can be affected in part by the buffer components and additives that are generally employed for purification and stabilization of proteins, hence, necessitate their removal by tedious and time-consuming procedures before proteolysis can occur. To address this issue, we examined the effect of elution buffers used for common affinity based purifications, salt ions, stability/solubility and reducing agents, and detergents on the activity of the human rhinovirus 3C protease using three different fusion proteins at 4°C, a temperature of choice for purification of many proteins. The results show that the human rhinovirus 3C protease performs better at 4°C than the frequently used tobacco etch virus protease and its activity was insensitive to most of the experimental conditions tested. Though number of fusion proteins tested is limited, we expect that these finding will facilitate the use of the human rhinovirus 3C protease in recombinant protein production for pharmaceutical and biotechnological applications. PMID:27093053

  16. Activity of the Human Rhinovirus 3C Protease Studied in Various Buffers, Additives and Detergents Solutions for Recombinant Protein Production.

    PubMed

    Ullah, Raheem; Shah, Majid Ali; Tufail, Soban; Ismat, Fouzia; Imran, Muhammad; Iqbal, Mazhar; Mirza, Osman; Rhaman, Moazur

    2016-01-01

    Proteases are widely used to remove affinity and solubility tags from recombinant proteins to avoid potential interference of these tags with the structure and function of the fusion partner. In recent years, great interest has been seen in use of the human rhinovirus 3C protease owing to its stringent sequence specificity and enhanced activity. Like other proteases, activity of the human rhinovirus 3C protease can be affected in part by the buffer components and additives that are generally employed for purification and stabilization of proteins, hence, necessitate their removal by tedious and time-consuming procedures before proteolysis can occur. To address this issue, we examined the effect of elution buffers used for common affinity based purifications, salt ions, stability/solubility and reducing agents, and detergents on the activity of the human rhinovirus 3C protease using three different fusion proteins at 4°C, a temperature of choice for purification of many proteins. The results show that the human rhinovirus 3C protease performs better at 4°C than the frequently used tobacco etch virus protease and its activity was insensitive to most of the experimental conditions tested. Though number of fusion proteins tested is limited, we expect that these finding will facilitate the use of the human rhinovirus 3C protease in recombinant protein production for pharmaceutical and biotechnological applications. PMID:27093053

  17. Investigation of the effect of Ag addition on the critical current density of the high-temperature superconductor Nd1.85Ce0.15CuO4

    NASA Astrophysics Data System (ADS)

    Radhikesh Raveendran, N.; Vinod, K.; Amaladass, E. P.; Janaki, J.; Mani, Awadhesh

    2016-07-01

    We have synthesized a Nd1.85Ce0.15CuO4 + Ag composite system with the aim of studying the effect of Ag addition in the electron-doped system Nd1.85Ce0.15CuO4 on its superconducting and magnetic properties. Measurements of magnetization using a vibration sample magnetometer indicate a systematic increase in diamagnetic shielding upon Ag addition. A subsequent analysis of the critical current density using the Bean model indicates a small but significant increase in intra-grain critical current density upon Ag addition. From the study of the dependence of electrical resistivity on the temperature and electrical current, an increase in inter-granular critical current has also been evidenced upon Ag addition. These results correlate well with the earlier reports of a similar improvement in the properties on the hole-doped ceramic superconductor/Ag composites. Possible reasons for the enhancement of JC have been described and discussed. Magnetic characterization by AC susceptibility using a SQUID magnetometer has been presented for a representative composition, which enabled delineation of the inter- and intra-granular transitions.

  18. Meta-analysis of high-latitude nitrogen-addition and warming studies imply ecological mechanisms overlooked by land models

    DOE PAGESBeta

    Bouskill, N. J.; Riley, W. J.; Tang, J.

    2014-08-18

    Accurate representation of ecosystem processes in land models is crucial for reducing predictive uncertainty in energy and greenhouse gas feedbacks with the atmosphere. Here we describe an observational and modeling meta-analysis approach to benchmark land models, and apply the method to the land model CLM4.5 with two versions of belowground biogeochemistry. We focused our analysis on the above and belowground high-latitude ecosystem responses to warming and nitrogen addition, and identified mechanisms absent, or poorly parameterized in CLM4.5. While the two model versions predicted similar trajectories for soil carbon stocks following both types of perturbation, other variables (e.g., belowground respiration) differedmore » from the observations in both magnitude and direction, indicating the underlying mechanisms are inadequate for representing high-latitude ecosystems. The observational synthesis attribute these differences to missing representations of microbial dynamics, characterization of above and belowground functional processes, and nutrient competition. We use the observational meta-analyses to discuss potential approaches to improving the current models (e.g., the inclusion of dynamic vegetation or different microbial functional guilds), however, we also raise a cautionary note on the selection of data sets and experiments to be included in a meta-analysis. For example, the concentrations of nitrogen applied in the synthesized field experiments (average =72 kg ha-1 yr-1) are many times higher than projected soil nitrogen concentrations (from nitrogen deposition and release during mineralization), which preclude a rigorous evaluation of the model responses to nitrogen perturbation. Overall, we demonstrate here that elucidating ecological mechanisms via meta-analysis can identify deficiencies in both ecosystem models and empirical experiments.« less

  19. Multiple Stressors in Agricultural Streams: A Mesocosm Study of Interactions among Raised Water Temperature, Sediment Addition and Nutrient Enrichment

    PubMed Central

    Piggott, Jeremy J.; Lange, Katharina; Townsend, Colin R.; Matthaei, Christoph D.

    2012-01-01

    Changes to land use affect streams through nutrient enrichment, increased inputs of sediment and, where riparian vegetation has been removed, raised water temperature. We manipulated all three stressors in experimental streamside channels for 30 days and determined the individual and pair-wise combined effects on benthic invertebrate and algal communities and on leaf decay, a measure of ecosystem functioning. We added nutrients (phosphorus+nitrogen; high, intermediate, natural) and/or sediment (grain size 0.2 mm; high, intermediate, natural) to 18 channels supplied with water from a nearby stream. Temperature was increased by 1.4°C in half the channels, simulating the loss of upstream and adjacent riparian shade. Sediment affected 93% of all biological response variables (either as an individual effect or via an interaction with another stressor) generally in a negative manner, while nutrient enrichment affected 59% (mostly positive) and raised temperature 59% (mostly positive). More of the algal components of the community responded to stressors acting individually than did invertebrate components, whereas pair-wise stressor interactions were more common in the invertebrate community. Stressors interacted often and in a complex manner, with interactions between sediment and temperature most common. Thus, the negative impact of high sediment on taxon richness of both algae and invertebrates was stronger at raised temperature, further reducing biodiversity. In addition, the decay rate of leaf material (strength loss) accelerated with nutrient enrichment at ambient but not at raised temperature. A key implication of our findings for resource managers is that the removal of riparian shading from streams already subjected to high sediment inputs, or land-use changes that increase erosion or nutrient runoff in a landscape without riparian buffers, may have unexpected effects on stream health. We highlight the likely importance of intact or restored buffer strips, both

  20. Additive contributions of childhood adversity and recent stressors to inflammation at midlife: Findings from the MIDUS study.

    PubMed

    Hostinar, Camelia E; Lachman, Margie E; Mroczek, Daniel K; Seeman, Teresa E; Miller, Gregory E

    2015-11-01

    We examined the joint contributions of self-reported adverse childhood experiences (ACEs) and recent life events (RLEs) to inflammation at midlife, by testing 3 competing theoretical models: stress generation, stress accumulation, and early life stress sensitization. We aimed to identify potential mediators between adversity and inflammation. Participants were 1,180 middle-aged and older adults from the Midlife in the United States (MIDUS) Biomarker Project (M age = 57.3 years, SD = 11.5; 56% female). A composite measure of inflammation was derived from 5 biomarkers: serum levels of C-reactive protein, interleukin-6, fibrinogen, E-selectin, and ICAM-1. Participants provided self-report data regarding ACEs, RLEs, current lifestyle indices (cigarette smoking, alcohol consumption, physical exercise, waist circumference), current depressive symptoms, and demographic/biomedical characteristics. We also used indices of hypothalamic-pituitary-adrenocortical outflow (12-hr urinary cortisol) and sympathetic nervous system output (12-hr urinary norepinephrine and epinephrine). Analyses indicated that ACEs and RLEs were independently associated with higher levels of inflammation, controlling for each other's effects. Their interaction was not significant. The results were consistent with the hypothesis that associations between ACEs and inflammation were mediated through higher urinary norepinephrine output, greater waist circumference, smoking, and lower levels of exercise, whereas higher waist circumference and more smoking partially mediated the association between RLEs and inflammation. In support of the stress accumulation model, ACEs and RLEs had unique and additive contributions to inflammation at midlife, with no evidence of synergistic effects. Results also suggested that norepinephrine output and lifestyle indices may help explain how prior stressors foster inflammation at midlife. PMID:26389605

  1. Photometric Studies of Two Neglected Eclipsing Binaries AX Cassiopeia and V1107 Cassiopeia with Possibly Additional Companions

    NASA Astrophysics Data System (ADS)

    Yang, Yuangui; Li, Kai; Li, Qun; Dai, Haifeng

    2016-04-01

    New photometry for two eclipsing binaries, AX Cas and V1107 Cas, was carried out during the 2014-2015 observing season. With an updated version of the W-D program, photometric solutions were simultaneously derived from BV light curves. Results indicate that AX Cas is a semi-detached binary with a mass ratio of q=0.400(+/- 0.003) and a fill-out factor of {f}p=88.1(+/- 0.5)%, while V1107 Cas is a contact one with a mass ratio of q=0.667(+/- 0.003) and a degree of contact of f=11.3%(+/- 0.3%). Based on all collected times of light minimum together with newly observed data, we constructed the (O-C) curves for the two systems. From the period analysis, it is found that orbital period variations may evidently appear that show light-time effect. The modulated period and amplitude are {P}{mod}=17.63(+/- 0.17)\\quad {years} and A=0\\buildrel{{d}}\\over{.} 0133(+/- 0\\buildrel{{d}}\\over{.} 0016) for AX Cas and {P}{mod}=7.23(+/- 0.14)\\quad {years} and A=0\\buildrel{{d}}\\over{.} 0023(+/- 0\\buildrel{{d}}\\over{.} 0002) for V1107 Cas, respectively. From 26 EB/EW binaries with only cyclic variations, we derived the relation between periods and total masses, indicating that mass loss from the system occurs from the semi-detached configuration to the contact case. The cyclic oscillations for 22 sample stars (including AX Cas and V1107 Cas) may be attributed to third bodies. Additional companions could remove angular momentum from the central systems, which may play a key role in the evolutionary process.

  2. Were There "Additional Foreseeable Risks" in the SUPPORT Study? Lessons Not Learned from the ARDSnet Clinical Trials.

    PubMed

    Silverman, Henry J; Dreyfuss, Didier

    2015-01-01

    Even though the interventions were adapted from standard clinical practice, the way they were provided meant that the care given infants in the study was distinctly different from standard care, with different risk profiles. Parents should have been informed about those differences. PMID:25530226

  3. PILOT-SCALE STUDIES ON THE EFFECT OF BROMINE ADDITION ON THE EMISSIONS OF CHLORINATED ORGANIC COMBUSTION BY-PRODUCTS

    EPA Science Inventory

    The paper reports on a study to evaluate organic combustion by-product emissions while feeding varying amounts of bromine (Br) and chlorine (Cl) into a pilot-scale incinerator burning surrogate waste materials. (NOTE: Adding brominated organic compounds to a pilot-scale incinerat...

  4. Study of Two Graphic Symbol-Teaching Methods for Individuals with Physical Disabilities and Additional Learning Difficulties

    ERIC Educational Resources Information Center

    Emms, Laila; Gardner, Hilary

    2010-01-01

    The primary purpose of this study was to establish whether contrasting teaching methods had an effect on performance accuracy in the recall of graphic symbols. The secondary purpose was to establish whether the iconicity of symbols had an effect on performance accuracy. A direct symbol-teaching method and a contextual symbol-teaching method were…

  5. A study of tetrabromobisphenol A (TBBA) as a flame retardant additive for Li-ion battery electrolytes

    NASA Astrophysics Data System (ADS)

    Belov, Dmitry G.; Shieh, D. T.

    2014-02-01

    Electrochemical behavior and flammability of tetrabromobisphenol A (TBBA)-mixed electrolyte solutions are investigated using 1 mol L-1 LiPF6-EC:EMC (1:2 vol.%) with 0 wt.% (reference electrolyte) and 1-3 wt.% of TBBA. The cycling performance (at room and elevated temperature) and rate capability of the 18650 cell (LiMn2O4:Li(Ni1/3Co1/3Mn1/3)O2 (8:2)/Li4Ti5O12) cell containing TBBA-mixed electrolyte is similar to that of cell containing the reference electrolyte. A detailed analysis of the surface on both the anode and the cathode electrodes via X-ray photoelectron spectroscopy (XPS) indicated that the cathode electrode contains more Br components than the anode electrode. Within the first few cycles, on the positive electrode, we observe competing redox processes between the cathode material containing Mn and TBBA, which generate hydroxy radicals and other by-products. This process and the electrochemical reductive decomposition of TBBA to HBr, Br2 and bisphenole A are responsible for the increased flame retardant properties of the electrolyte containing TBBA. Safety tests were performed using an 18650 cell showed that even 1 wt.% of TBBA in the electrolyte significantly reduces cell flammability.

  6. Study on biodegradation of Mazut by newly isolated strain Enterobacter cloacae BBRC10061: improving and kinetic investigation

    PubMed Central

    2013-01-01

    Mazut as a source content of various hydrocarbons is hard to be degraded and its cracking could turn mazut into useful materials. Nevertheless degradation of mazut by routine methods is too expensive but application of indigenous microorganisms as biocatalysts could be effective and important to lower the costs and expand its consumption. Mazut biodegradation can be improved using various strategies; Therefore in this study newly isolated strain Enterobacter cloacae BBRC 10061 was used in a method of gradual addition of mazut into medium and its results were compared with simple addition method. To investigate degradation of mazut by BBRC 10061, influence of increase of mazut concentration was assayed based on gradual addition method. Also different kinetic models were used to evaluate kinetics of the process. Results showed that gradual addition method has been a beneficial technique for improvement of mazut degradation because bacterial induction to produce biosurfactant and essential enzymes for cracking mazut was higher during process. Although addition of more mazut increased the rate of biodegradation but percentage of degradation decreased. pH of medium decreased during biodegradation period while electric potential increased. Also the biodegradation kinetics was not fitted with the biokinetic models; therefore kinetics of biodegradation of mazut has to be studied by new models. PMID:23369455

  7. MO-G-BRF-09: Investigating Magnetic Field Dose Effects in Mice: A Monte Carlo Study

    SciTech Connect

    Rubinstein, A; Guindani, M; Followill, D; Melancon, A; Hazle, J; Court, L

    2014-06-15

    Purpose: In MRI-linac treatments, radiation dose distributions are affected by magnetic fields, especially at high-density/low-density interfaces. Radiobiological consequences of magnetic field dose effects are presently unknown; therefore, preclinical studies are needed to ensure the safe clinical use of MRI-linacs. This study investigates the optimal combination of beam energy and magnetic field strength needed for preclinical murine studies. Methods: The Monte Carlo code MCNP6 was used to simulate the effects of a magnetic field when irradiating a mouse-sized lung phantom with a 1.0cmx1.0cm photon beam. Magnetic field effects were examined using various beam energies (225kVp, 662keV[Cs-137], and 1.25MeV[Co-60]) and magnetic field strengths (0.75T, 1.5T, and 3T). The resulting dose distributions were compared to Monte Carlo results for humans with various field sizes and patient geometries using a 6MV/1.5T MRI-linac. Results: In human simulations, the addition of a 1.5T magnetic field caused an average dose increase of 49% (range:36%–60%) to lung at the soft tissue-to-lung interface and an average dose decrease of 30% (range:25%–36%) at the lung-to-soft tissue interface. In mouse simulations, the magnetic fields had no effect on the 225kVp dose distribution. The dose increases for the Cs-137 beam were 12%, 33%, and 49% for 0.75T, 1.5T, and 3.0T magnetic fields, respectively while the dose decreases were 7%, 23%, and 33%. For the Co-60 beam, the dose increases were 14%, 45%, and 41%, and the dose decreases were 18%, 35%, and 35%. Conclusion: The magnetic field dose effects observed in mouse phantoms using a Co-60 beam with 1.5T or 3T fields and a Cs-137 beam with a 3T field compare well with those seen in simulated human treatments with an MRI-linac. These irradiator/magnet combinations are suitable for preclinical studies investigating potential biological effects of delivering radiation therapy in the presence of a magnetic field. Partially funded by Elekta.

  8. Investigation of hemodynamics during cardiopulmonary bypass: A multiscale multiphysics fluid-structure-interaction study.

    PubMed

    Neidlin, Michael; Sonntag, Simon J; Schmitz-Rode, Thomas; Steinseifer, Ulrich; Kaufmann, Tim A S

    2016-04-01

    Neurological complications often occur during cardiopulmonary bypass (CPB). Hypoperfusion of brain tissue due to diminished cerebral autoregulation (CA) and thromboembolism from atherosclerotic plaque reduce the cerebral oxygen supply and increase the risk of perioperative stroke. To improve the outcome of cardiac surgeries, patient-specific computational fluid dynamic (CFD) models can be used to investigate the blood flow during CPB. In this study, we establish a computational model of CPB which includes cerebral autoregulation and movement of aortic walls on the basis of in vivo measurements. First, the Baroreflex mechanism, which plays a leading role in CA, is represented with a 0-D control circuit and coupled to the 3-D domain with differential equations as boundary conditions. Additionally a two-way coupled fluid-structure interaction (FSI) model with CA is set up. The wall shear stress (WSS) distribution is computed for the whole FSI domain and a comparison to rigid wall CFD is made. Constant flow and pulsatile flow CPB is considered. Rigid wall CFD delivers higher wall shear stress values than FSI simulations, especially during pulsatile perfusion. The flow rates through the supraaortic vessels are almost not affected, if considered as percentages of total cannula output. The developed multiphysic multiscale framework allows deeper insights into the underlying mechanisms during CPB on a patient-specific basis. PMID:26908181

  9. Investigation and macroscopic anatomical study of referred pain in patients with hip disease.

    PubMed

    Sakamoto, Junya; Morimoto, Yosuke; Ishii, Shun; Nakano, Jiro; Manabe, Yoshitaka; Okita, Minoru; Tsurumoto, Toshiyuki

    2014-02-01

    [Purpose] The aim of this study was to examine the incidence and patterns of referred pain in patients with hip disease, as well as the nerve distribution in the hip and knee joints of 2 cadavers. [Subjects and Methods] A total of 113 patients with hip joint disease were included in the investigation. The incidence of regional pain and referred pain patterns were evaluated before and after arthroplasty. Two cadavers were macroscopically observed to verify the nerve innervation of the hip and knee joints. [Results] Anterior knee pain was observed preoperatively in 13.3% (in resting) and 33.6% (in motion) of the patients, which was comparable with the incidence of greater trochanter pain. In addition, the preoperative incidence rates of knee pain in resting and motion markedly decreased postoperatively. Of note is the remarkable incidence of pain radiating to the ventral lower limb. An anteromedial innervation was determined in the cadavers by the articular branches of the obturator and femoral nerve, which supply small branches to the knee joints. [Conclusion] Our results suggest that the distribution of the incidence of pain among the patients with hip disease is diverse owing to the sensory distribution of the femoral and obturator nerves. PMID:24648632

  10. Does addition of `mud-pack and hot pool treatment' to patient education make a difference in fibromyalgia patients? A randomized controlled single blind study

    NASA Astrophysics Data System (ADS)

    Bağdatlı, Ali Osman; Donmez, Arif; Eröksüz, Rıza; Bahadır, Güler; Turan, Mustafa; Erdoğan, Nergis

    2015-12-01

    The aim of this randomized controlled single-blind study is to explore whether addition of mud-pack and hot pool treatments to patient education make a significant difference in short and mild term outcomes of the patients with fibromyalgia. Seventy women with fibromyalgia syndrome were randomly assigned to either balneotherapy with mud-pack and hot pool treatments (35) or control (35) groups. After randomization, five patients from balneotherapy group and five patients from control group were dropped out from the study with different excuses. All patients had 6-h patient education programme about fibromyalgia syndrome and were given a home exercise programme. The patients in balneotherapy group had heated pool treatment at 38 °C for 20 min a day, and mud-pack treatment afterwards on back region at 45 °C. Balneotherapy was applied on weekdays for 2 weeks. All patients continued to take their medical treatment. An investigator who was blinded to the intervention assessed all the patients before and after the treatment, at the first and the third months of follow-up. Outcome measures were FIQ, BDI and both patient's and physician's global assessments. Balneotherapy group was significantly better than control group at after the treatment and at the end of the first month follow-up assessments in terms of patient's and physician's global assessment, total FIQ score, and pain intensity, fatigue, non-refreshed awaking, stiffness, anxiety and depression subscales of FIQ. No significant difference was found between the groups in terms of BDI scores. It is concluded that patient education combined with 2 weeks balneotherapy application has more beneficial effects in patients with fibromyalgia syndrome as compared to patient education alone.

  11. Investigation of Inquiry-based Science Pedagogy among Middle Level Science Teachers: A Qualitative Study

    NASA Astrophysics Data System (ADS)

    Weiland, Sunny Minelli

    related to research question #2) What are preferred instructional strategies for implementation in middle level science classrooms? and topical sub-question #2) How do middle level science teachers structure instruction. The theme that emerged was needs of students. Analysis of the data revealed one theme related to research question #3) How do middle level science teachers perceive the relationship between science instruction and student learning? and topical sub-question #3) How do middle level science teachers view their role in relation to student learning? This theme is meaning making. Analysis of the data related to meaning making revealed two sub-themes of application and relationships. It is clear that middle level science teachers have a vision for inquiry-based science instruction, but implementation is inhibited by a variety of factors including curricular programming that is very broad and lacks depth, the scheduling of time and resources for science, and the absence of a clear model of inquiry-based instruction. In addition, only one participant referenced students investigating their own authentic questions and no participants reflected on the importance of students using evidence in their explanations of scientific phenomenon. Additionally, participants continually reflected on the needs of their students informing instructional practices, and it is wondered if there is a clear understanding among middle level teachers of how students learn science. Real world applications were recognized as important within science learning and the researcher questions whether teachers of science have adequate opportunities to explore real world application of science concepts throughout their careers in order to foster connections within the classroom. These findings support the need for strong, job-embedded professional development, the cultivation of learning communities dedicated to the investigation and implementation of inquiry-based science, the focusing of

  12. Dexamethasone as An Additive to Bupivacaine in Fascia Lliaca Compartment Block: A Prospective, Randomized and Double Blind Study

    PubMed Central

    Kumar N, Suresh; N, Kiran; Sebastian, Don; Gowda RM, Punith

    2014-01-01

    Background: Patients with fracture femur experience severe pain on movement during positioning for spinal anaesthesia. Fascia Iliaca Compartment Block (FICB) has been used effectively for providing analgesia during positioning of the patient for spinal anaesthesia. Aim: To test the hypothesis that, adding dexamethasone would significantly prolong the duration of Bupivacaine in FICB. Materials and Methods: Sixty patients aged 18 to 80 years posted for ORIF (Open Reduction and Internal Fixation) of fracture femur were included to receive FICB. This was a prospective, randomized, double blind study done at tertiary medical college hospital. Thirty patients received 38ml of 0.25 % bupivacaine with 2ml saline and another 30 patients received 38ml of 0.25 % bupivacaine with 2ml dexamethasone (8mg). Thirty minutes after FICB, patient satisfaction during positioning for spinal anesthesia was recorded. In the post-operative period, duration of analgesia and the total doses of rescue analgesics were recorded in both the groups. Results: Patients who received Bupivacaine with dexamethasone had significant prolongation of analgesia and required fewer doses of rescue analgesics as compared to patients who received Bupivacaine alone for FICB. However, the onset of analgesia, VAS scores and patient satisfaction during positioning for spinal anaesthesia were similar in both groups. Conclusion: Our study shows that adding Dexamethasone (8mg) to Bupivacaine for FICB significantly prolonged the duration of block and decreased the requirement of rescue analgesics as compared to patients who received Bupivacaine alone. FICB is relatively easy and safe to perform. In our study we did not encounter any complication while doing the procedures and also by adding dexamethasone. PMID:25302209

  13. Investigating the Facilitator's Role during the Lesson Study Process in High Schools

    ERIC Educational Resources Information Center

    Vaughn, Stephanie Michelle

    2012-01-01

    Lesson study, a teaching and learning strategy used in Japan, is a new area of consideration for teacher professional development in the United States. An important component of the lesson study process is the role of the facilitator. The intent of this study was to investigate the role of the facilitator in the lesson study process relative to…

  14. Epithelioid rhabdomyosarcoma: a clinicopathological study of seven additional cases supporting a distinctive variant with aggressive biological behaviour.

    PubMed

    Yu, Lin; Lao, I Weng; Wang, Jian

    2015-12-01

    We present our experience with seven cases of epithelioid rhabdomyosarcoma (RMS) to further characterise its clinicopathological features. There were five males and two females with ages ranging from 19 to 84 years (mean 56 years). Four tumours occurred in the somatic soft tissue, two in organs and one in the bone. The mean tumour size was 10.7 cm (range 3.5-15 cm). Histologically, six tumours were characterised by sheet-like growth of uniform epithelioid cells with large vesicular nuclei, prominent nucleoli, high mitotic activity and moderate to abundant amphophilic-to-eosinophilic cytoplasm. One tumour was composed of dyscohesive cells with rhabdoid appearance embedded in a myxoid matrix. Features suggestive of rhabdomyoblastic differentiation were absent. However, immunohistochemical study revealed skeletal muscle differentiation in all cases. Of note, focal expression of epithelial markers with co-expression of neuroendocrine markers was noted in five and three cases, respectively. Of six patients with follow-up, one experienced local recurrence and three developed metastases. To date, three patients have died of disease within 14 months. This study further demonstrates that epithelioid RMS represents a distinct variant of RMS with an aggressive behaviour. It may be misdiagnosed as poorly differentiated neuroendocrine carcinoma due to co-expression of epithelial and neuroendocrine markers. PMID:26517641

  15. Additional treatment of wastewater reduces endocrine disruption in wild fish--a comparative study of tertiary and advanced treatments.

    PubMed

    Baynes, Alice; Green, Christopher; Nicol, Elizabeth; Beresford, Nicola; Kanda, Rakesh; Henshaw, Alan; Churchley, John; Jobling, Susan

    2012-05-15

    Steroid estrogens are thought to be the major cause of feminization (intersex) in wild fish. Widely used wastewater treatment technologies are not effective at removing these contaminants to concentrations thought to be required to protect aquatic wildlife. A number of advanced treatment processes have been proposed to reduce the concentrations of estrogens entering the environment. Before investment is made in such processes, it is imperative that we compare their efficacy in terms of removal of steroid estrogens and their feminizing effects with other treatment options. This study assessed both steroid removal and intersex induction in adult and early life stage fish (roach, Rutilus rutilus). Roach were exposed directly to either secondary (activated sludge process (ASP)), tertiary (sand filtrated (SF)), or advanced (chlorine dioxide (ClO(2)), granular activated charcoal (GAC)) treated effluents for six months. Surprisingly, both the advanced GAC and tertiary SF treatments (but not the ClO(2) treatment) significantly removed the intersex induction associated with the ASP effluent; this was not predicted by the steroid estrogen measurements, which were higher in the tertiary SF than either the GAC or the ClO(2). Therefore our study highlights the importance of using both biological and chemical analysis when assessing new treatment technologies. PMID:22500691

  16. Theoretical study of the molecular force field and vibration analysis of the hydrogen cyanide addition compound with boron tribromide.

    PubMed

    Hase, Y

    2010-01-01

    An extensive HF, MP2, B3LYP and CCSD study of the molecular structure, force field and normal vibrations has been carried out for the hydrogen cyanide compound with boron tribromide. Most of the calculations agree that the HCN-BBr(3) molecule belongs to C(3v) point group and has a N-B length of 1.55-1.70 A and a N-B-Br angle of 103-105 degrees. These calculations also have estimated the missing low-wavenumber fundamentals in the 190 (nu(5)), 150 (nu(9)) and 105 cm(-1) (nu(10)) regions, instead of the supposed fundamentals at 207, 188 and 150 cm(-1), respectively, based on the combination bands. The quantum chemical force constants, by the B3LYP/6-31G and CCSD/3-21G calculations, have been adjusted by the scaling factors to reproduce the fundamentals in the literature [3] to include the bands below 200 cm(-1) proposed in this study. Normal coordinate analysis using the scaled force constants has been performed to interpret the molecular vibrations of four isotopic molecules, HCN-(10)BBr(3), HCN-(11)BBr(3), DCN-(10)BBr(3) and DCN-(11)BBr(3). PMID:19955013

  17. Theoretical study of the molecular force field and vibration analysis of the hydrogen cyanide addition compound with boron tribromide

    NASA Astrophysics Data System (ADS)

    Hase, Y.

    2010-01-01

    An extensive HF, MP2, B3LYP and CCSD study of the molecular structure, force field and normal vibrations has been carried out for the hydrogen cyanide compound with boron tribromide. Most of the calculations agree that the HCN-BBr 3 molecule belongs to C3v point group and has a N-B length of 1.55-1.70 Å and a N-B-Br angle of 103-105°. These calculations also have estimated the missing low-wavenumber fundamentals in the 190 ( ν5), 150 ( ν9) and 105 cm -1 ( ν10) regions, instead of the supposed fundamentals at 207, 188 and 150 cm -1, respectively, based on the combination bands. The quantum chemical force constants, by the B3LYP/6-31G and CCSD/3-21G calculations, have been adjusted by the scaling factors to reproduce the fundamentals in the literature [3] to include the bands below 200 cm -1 proposed in this study. Normal coordinate analysis using the scaled force constants has been performed to interpret the molecular vibrations of four isotopic molecules, HCN- 10BBr 3, HCN- 11BBr 3, DCN- 10BBr 3 and DCN- 11BBr 3.

  18. Investigation of Inquiry-based Science Pedagogy among Middle Level Science Teachers: A Qualitative Study

    NASA Astrophysics Data System (ADS)

    Weiland, Sunny Minelli

    related to research question #2) What are preferred instructional strategies for implementation in middle level science classrooms? and topical sub-question #2) How do middle level science teachers structure instruction. The theme that emerged was needs of students. Analysis of the data revealed one theme related to research question #3) How do middle level science teachers perceive the relationship between science instruction and student learning? and topical sub-question #3) How do middle level science teachers view their role in relation to student learning? This theme is meaning making. Analysis of the data related to meaning making revealed two sub-themes of application and relationships. It is clear that middle level science teachers have a vision for inquiry-based science instruction, but implementation is inhibited by a variety of factors including curricular programming that is very broad and lacks depth, the scheduling of time and resources for science, and the absence of a clear model of inquiry-based instruction. In addition, only one participant referenced students investigating their own authentic questions and no participants reflected on the importance of students using evidence in their explanations of scientific phenomenon. Additionally, participants continually reflected on the needs of their students informing instructional practices, and it is wondered if there is a clear understanding among middle level teachers of how students learn science. Real world applications were recognized as important within science learning and the researcher questions whether teachers of science have adequate opportunities to explore real world application of science concepts throughout their careers in order to foster connections within the classroom. These findings support the need for strong, job-embedded professional development, the cultivation of learning communities dedicated to the investigation and implementation of inquiry-based science, the focusing of

  19. Design of the SHAPE-2 study: the effect of physical activity, in addition to weight loss, on biomarkers of postmenopausal breast cancer risk

    PubMed Central

    2013-01-01

    Background Physical inactivity and overweight are two known risk factors for postmenopausal breast cancer. Former exercise intervention studies showed that physical activity influences sex hormone levels, known to be related to postmenopausal breast cancer, mainly when concordant loss of body weight was achieved. The question remains whether there is an additional beneficial effect of physical activity when weight loss is reached. The aim of this study is to investigate the effect attributable to exercise on postmenopausal breast cancer risk biomarkers, when equivalent weight loss is achieved compared with diet-induced weight loss. Design The SHAPE-2 study is a three-armed, multicentre trial. 243 sedentary, postmenopausal women who are overweight or obese (BMI 25–35 kg/m2) are enrolled. After a 4-6 week run-in period, wherein a baseline diet is prescribed, women are randomly allocated to (1) a diet group, (2) an exercise group or (3) a control group. The aim of both intervention groups is to lose an amount of 5–6 kg body weight in 10–14 weeks. The diet group follows an energy restricted diet and maintains the habitual physical activity level. The exercise group participates in a 16-week endurance and strength training programme of 4 hours per week. Furthermore, they are prescribed a moderate caloric restriction. The control group is asked to maintain body weight and continue the run-in baseline diet. Measurements include blood sampling, questionnaires, anthropometrics (weight, height, waist and hip circumference), maximal cycle exercise test (VO2peak), DEXA-scan (body composition) and abdominal MRI (subcutaneous and visceral fat). Primary outcomes are serum levels of oestradiol, oestrone, testosterone and sex hormone binding globulin (SHBG). Discussion This study will give insight in the potential attributable effect of physical activity on breast cancer risk biomarkers and whether this effect is mediated by changes in body composition, in postmenopausal

  20. From Addition to Multiplication ... and Back: The Development of Students' Additive and Multiplicative Reasoning Skills

    ERIC Educational Resources Information Center

    Van Dooren, Wim; De Bock, Dirk; Verschaffel, Lieven

    2010-01-01

    This study builds on two lines of research that have so far developed largely separately: the use of additive methods to solve proportional word problems and the use of proportional methods to solve additive word problems. We investigated the development with age of both kinds of erroneous solution methods. We gave a test containing missing-value…

  1. The Study on Thermal Expansion of Ceramic Composites with Addition of ZrW2O8

    NASA Astrophysics Data System (ADS)

    Dedova, E. S.; Shadrin, V. S.; Petrushina, M. Y.; Kulkov, S. N.

    2016-02-01

    The studies on structure, phase composition and thermal properties of (Al2O3 - 20 wt% ZrO2) - ZrW2O8 ceramic composites obtained using nanosized, initial powders were conducted. Homogeneously distributed white particles on the polished surface of composites were observed. Phase composition of the composites was represented with corundum, monoclinic ZrO2 and two modifications of ZrW2O8 (tetragonal and cubic). Linear thermal expansion coefficient values of the composites were determined. The difference in experimental and calculated coefficient of thermal expansion values for composites obtained may be attributed to phase transformations, features of the structure, internal stresses due to thermal expansion mismatch, which contribute significantly to thermal expansion of the ceramic composites.

  2. Literature review and need for additional study of surface-water quality in the Cuyahoga Valley National Recreation Area, Ohio

    USGS Publications Warehouse

    Childress, C.J.

    1984-01-01

    The Cuyahoga Valley National Recreation Area encompasses about 24 miles of the middle reach of the Cuyahoga River and parts of four major tributaries -- Furnace Run, Brandywine Creek, Chippewa Creek, and TInkers Creek. Water quality in this reach does not meet Ohio water-quality standards for dissolved oxygen, fecal bacteria, ammonia, and lead. Point sources of effluent contribute contaminants. On the basis of a review of scientific and technical literature, National Park Service management goals, and water-quality data collected by the U.S. Geological Survey, three subject areas for future study are suggested: (1) The dissolved oxygen regime, (2) chemical quality of base flow, and (3) quality of storm-water runoff.

  3. Additional perspectives on chronic kidney disease of unknown aetiology (CKDu) in Sri Lanka – lessons learned from the WHO CKDu population prevalence study

    PubMed Central

    2014-01-01

    The recent emergence of an apparently new form of chronic kidney disease of unknown aetiology (CKDu) has become a serious public health crisis in Sri Lanka. CKDu is slowly progressive, irreversible, and asymptomatic until late stages, and is not attributable to hypertension, diabetes, or other known aetiologies. In response to the scope and severity of the emerging CKDu health crisis, the Sri Lanka Ministry of Health and the World Health Organization initiated a collaborative research project from 2009 through 2012 to investigate CKDu prevalence and aetiology. The objective of this paper is to discuss the recently published findings of this investigation and present additional considerations and recommendations that may enhance subsequent investigations designed to identify and understand CKDu risk factors in Sri Lanka or other countries. PMID:25069485

  4. Electrofishing and the effects of depletion sampling on fish health: A review and recommendations for additional study

    USGS Publications Warehouse

    Panek, F.M.; Densmore, Christine L.

    2011-01-01

    Depletion sampling in combination with multiple-pass electrofishing is an important fisheries management tool for wadeable streams. This combination of techniques has been used routinely by federal and state fishery management agencies for several decades as a reliable means to obtain quantitative data on trout populations or to describe fish community structure. In this paper we review the effects of electrofishing on fish and discuss this within the context of depletion sampling and multiple exposures of fishes to electric fields. The multiple wave forms most commonly used in sampling (alternating current, direct current, and pulsed direct current) are discussed as well as electrofishing induced response, injury and physiological stress. Fish that survive electrofishing injuries are more likely to suffer short and long-term adverse effects to their behavior, health, growth, or reproduction. Of greatest concern are the native, non-target species that may be subjected to multiple electrical shocks during the course of a 3-pass depletion survey. These exposures and their effects on the non-target species warrant further study as do the overall effects of electrofishing on populations and community structure. 

  5. Drinking Hydrogen-Rich Water Has Additive Effects on Non-Surgical Periodontal Treatment of Improving Periodontitis: A Pilot Study

    PubMed Central

    Azuma, Tetsuji; Yamane, Mayu; Ekuni, Daisuke; Kawabata, Yuya; Kataoka, Kota; Kasuyama, Kenta; Maruyama, Takayuki; Tomofuji, Takaaki; Morita, Manabu

    2015-01-01

    Oxidative stress is involved in the pathogenesis of periodontitis. A reduction of oxidative stress by drinking hydrogen-rich water (HW) might be beneficial to periodontal health. In this pilot study, we compared the effects of non-surgical periodontal treatment with or without drinking HW on periodontitis. Thirteen patients (3 women, 10 men) with periodontitis were divided into two groups: The control group (n = 6) or the HW group (n = 7). In the HW group, participants consumed HW 4–5 times/day for eight weeks. At two to four weeks, all participants received non-surgical periodontal treatment. Oral examinations were performed at baseline, two, four and eight weeks, and serum was obtained at these time points to evaluate oxidative stress. At baseline, there were no significant differences in periodontal status between the control and HW groups. The HW group showed greater improvements in probing pocket depth and clinical attachment level than the control group at two, four and eight weeks (p < 0.05). The HW group also exhibited an increased serum level of total antioxidant capacity at four weeks, compared to baseline (p < 0.05). Drinking HW enhanced the effects of non-surgical periodontal treatment, thus improving periodontitis. PMID:26783840

  6. Study of Fluorine Addition Influence in the Dielectric Constant of Diamond-Like Carbon Thin Film Deposited by Reactive Sputtering

    NASA Astrophysics Data System (ADS)

    Trippe, S. C.; Mansano, R. D.

    The hydrogenated amorphous carbon films (a-C:H) or DLC (Diamond-Like Carbon) films are well known for exhibiting high electrical resistivity, low dielectric constant, high mechanical hardness, low friction coefficient, low superficial roughness and also for being inert. In this paper, we produced fluorinated DLC films (a-C:F), and studied the effect of adding CF4 on the above-mentioned properties of DLC films. These films were produced by a reactive RF magnetron sputtering system using a target of pure carbon in stable graphite allotrope. We performed measurements of electrical characteristic curves of capacitance as a function of applied tension (C-V) and current as a function of the applied tension (I-V). We showed the dielectric constant (k) and the resistivity (ρ) as functions of the CF4 concentration. On films with 65% CF4, we found that k = 2.7, and on films with 70% CF4, ρ = 12.3 × 1011 Ω cm. The value of the electrical breakdown field to films with 70% CF4 is 5.3 × 106 V/cm.

  7. Decomposition of the fluoroethylene carbonate additive and the glue effect of lithium fluoride products for the solid electrolyte interphase: an ab initio study.

    PubMed

    Okuno, Yukihiro; Ushirogata, Keisuke; Sodeyama, Keitaro; Tateyama, Yoshitaka

    2016-03-28

    Additives in the electrolyte solution of lithium-ion batteries (LIBs) have a large impact on the performance of the solid electrolyte interphase (SEI) that forms on the anode and is a key to the stability and durability of LIBs. We theoretically investigated effects of fluoroethylene carbonate (FEC), a representative additive, that has recently attracted considerable attention for the enhancement of cycling stability of silicon electrodes and the improvement of reversibility of sodium-ion batteries. First, we intensively examined the reductive decompositions by ring-opening, hydrogen fluoride (HF) elimination to form a vinylene carbonate (VC) additive and intermolecular chemical reactions of FEC in the ethylene carbonate (EC) electrolyte, by using density functional theory (DFT) based molecular dynamics and the blue-moon ensemble technique for the free energy profile. The results show that the most plausible product of the FEC reductive decomposition is lithium fluoride (LiF), and that the reactivity of FEC to anion radicals is found to be inert compared to the VC additive. We also investigated the effects of the generated LiF on the SEI by using two model systems; (1) LiF molecules distributed in a model aggregate of organic SEI film components (SFCs) and (2) a LiF aggregate interfaced with the SFC aggregate. DFT calculations of the former system show that F atoms form strong bindings with the Li atoms of multiple organic SFC molecules and play as a joint connecting them. In the latter interface system, the LiF aggregate adsorbs the organic SFCs through the F-Li bindings. These results suggest that LiF moieties play the role of glue in the organic SFC within the SEI film. We also examined the interface structure between a LiF aggregate and a lithiated silicon anode, and found that they are strongly bound. This strong binding is likely to be related to the effectiveness of the FEC additive in the electrolyte for the silicon anode. PMID:26948716

  8. Additional Routes to Staphylococcus aureus Daptomycin Resistance as Revealed by Comparative Genome Sequencing, Transcriptional Profiling, and Phenotypic Studies

    PubMed Central

    Song, Yang; Rubio, Aileen; Jayaswal, Radheshyam K.; Silverman, Jared A.; Wilkinson, Brian J.

    2013-01-01

    Daptomycin is an extensively used anti-staphylococcal agent due to the rise in methicillin-resistant Staphylococcus aureus, but the mechanism(s) of resistance is poorly understood. Comparative genome sequencing, transcriptomics, ultrastructure, and cell envelope studies were carried out on two relatively higher level (4 and 8 µg/ml−1) laboratory-derived daptomycin-resistant strains (strains CB1541 and CB1540 respectively) compared to their parent strain (CB1118; MW2). Several mutations were found in the strains. Both strains had the same mutations in the two-component system genes walK and agrA. In strain CB1540 mutations were also detected in the ribose phosphate pyrophosphokinase (prs) and polyribonucleotide nucleotidyltransferase genes (pnpA), a hypothetical protein gene, and in an intergenic region. In strain CB1541 there were mutations in clpP, an ATP-dependent protease, and two different hypothetical protein genes. The strain CB1540 transcriptome was characterized by upregulation of cap (capsule) operon genes, genes involved in the accumulation of the compatible solute glycine betaine, ure genes of the urease operon, and mscL encoding a mechanosensitive chanel. Downregulated genes included smpB, femAB and femH involved in the formation of the pentaglycine interpeptide bridge, genes involved in protein synthesis and fermentation, and spa encoding protein A. Genes altered in their expression common to both transcriptomes included some involved in glycine betaine accumulation, mscL, ure genes, femH, spa and smpB. However, the CB1541 transcriptome was further characterized by upregulation of various heat shock chaperone and protease genes, consistent with a mutation in clpP, and lytM and sceD. Both strains showed slow growth, and strongly decreased autolytic activity that appeared to be mainly due to decreased autolysin production. In contrast to previous common findings, we did not find any mutations in phospholipid biosynthesis genes, and it appears there

  9. Structural-functional characterization of the cathodic haemoglobin of the conger eel Conger conger: molecular modelling study of an additional phosphate-binding site.

    PubMed Central

    Pellegrini, Mariagiuseppina; Giardina, Bruno; Verde, Cinzia; Carratore, Vito; Olianas, Alessandra; Sollai, Luigi; Sanna, Maria T; Castagnola, Massimo; di Prisco, Guido

    2003-01-01

    The protein sequence data for the alpha- and beta-chains have been deposited in the SWISS-PROT and TrEMBL protein knowledgebase under the accession numbers P83479 and P83478 respectively. The Conger conger (conger eel) haemoglobin (Hb) system is made of three components, one of which, the so-called cathodic Hb, representing approx. 20% of the total pigment, has been purified and characterized from both a structural and functional point of view. Stripped Hb showed a reverse Bohr effect, high oxygen affinity and slightly low cooperativity in the absence of any effector. Addition of saturating GTP strongly influences the pH dependence of the oxygen affinity, since the reverse Bohr effect, observed under stripped conditions, is converted into a small normal Bohr effect. A further investigation of the GTP effect on oxygen affinity, carried out by fitting its titration curve, demonstrated the presence of two independent binding sites. Therefore, on the basis of the amino acid sequence of the alpha- and beta-chains, which have been determined, a computer modelling study has been performed. The data suggest that C. conger cathodic Hb may bind organic phosphates at two distinct binding sites located along the central cavity of the tetramer by hydrogen bonds and/or electrostatic interactions with amino acid residues of both chains, which have been identified. Among these residues, the two Lys-alpha(G6) (where the letter refers to the haemoglobin helix and the number to the amino acid position in the helix) appear to have a key role in the GTP movement from the external binding region to the internal central cavity of the tetrameric molecule. PMID:12646043

  10. 78 FR 60291 - Investigational Device Exemptions for Early Feasibility Medical Device Clinical Studies...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-01

    ...The Food and Drug Administration (FDA) is announcing the availability of the guidance entitled ``Investigational Device Exemptions (IDEs) for Early Feasibility Medical Device Clinical Studies, Including Certain First in Human (FIH) Studies.'' Through the approaches announced in this guidance, FDA intends to facilitate early feasibility studies of medical devices, using appropriate risk......

  11. Investigating the Effectiveness of Individualized Feedback to Rating Behavior--A Longitudinal Study

    ERIC Educational Resources Information Center

    Knoch, Ute

    2011-01-01

    The effectiveness of individualized feedback on rater behavior has been investigated in several previous studies (e.g. Elder, Knoch, Barkhuizen, & von Randow, 2005; Lunt, Morton, & Wigglesworth, 1994; O'Sullivan & Rignall, 2007; Wigglesworth, 1993). The findings of these studies are somewhat inconclusive. However, all of these studies investigated…

  12. A Longitudinal Investigation into L2 Learners' Cognitive Processes during Study Abroad

    ERIC Educational Resources Information Center

    Ren, Wei

    2014-01-01

    The present study longitudinally investigates the cognitive processes of advanced L2 learners engaged in a multimedia task that elicited status-equal and status-unequal refusals in English during their study abroad. Data were collected three times by retrospective verbal report from 20 Chinese learners who were studying abroad over the course of…

  13. An Investigation of the Internal Structure of the Biggs Study Process Questionnaire.

    ERIC Educational Resources Information Center

    Watkins, David; Hattie, John

    1980-01-01

    Results of an Australian study of the Biggs Study Process Questionnaire (SPQ) are presented. The purposes of the research were to: (1) re-examine the SPQ's internal consistency; (2) explore dimensionality of the SPQ scales; and (3) investigate validity of Bigg's model of the study process complex through factor analysis. (Author/GK)

  14. Evidence-Based Communication Practices for Children with Visual Impairments and Additional Disabilities: An Examination of Single-Subject Design Studies

    ERIC Educational Resources Information Center

    Parker, Amy T.; Grimmett, Eric S.; Summers, Sharon

    2008-01-01

    This review examines practices for building effective communication strategies for children with visual impairments, including those with additional disabilities, that have been tested by single-subject design methodology. The authors found 30 studies that met the search criteria and grouped intervention strategies to align any evidence of the…

  15. Non-additive response of blends of rice and potato starch during heating at intermediate water contents: A differential scanning calorimetry and proton nuclear magnetic resonance study.

    PubMed

    Bosmans, Geertrui M; Pareyt, Bram; Delcour, Jan A

    2016-02-01

    The impact of different hydration levels, on gelatinization of potato starch (PS), rice starch (RS) and a 1:1 blend thereof, was investigated by differential scanning calorimetry and related to nuclear magnetic resonance proton distributions of hydrated samples, before and after heating. At 20% or 30% hydration, the visual appearance of all samples was that of a wet powder, and limited, if any, gelatinization occurred upon heating. At 30% hydration, changes in proton distributions were observed and related to plasticization of amorphous regions in the granules. At 50% hydration, the PS-RS blend appeared more liquid-like than other hydrated samples and showed more pronounced gelatinization than expected based on additive behavior of pure starches. This was due to an additional mobile water fraction in the unheated PS-RS blend, originating from differences in water distribution due to altered stacking of granules and/or altered hydration of PS due to presence of cations in RS. PMID:26304387

  16. A planning study investigating dual-gated volumetric arc stereotactic treatment of primary renal cell carcinoma

    SciTech Connect

    Devereux, Thomas; Pham, Daniel; Kron, Tomas; Foroudi, Farshad; Supple, Jeremy; Siva, Shankar

    2015-04-01

    This is a planning study investigating the dosimetric advantages of gated volumetric-modulated arc therapy (VMAT) to the end-exhale and end-inhale breathing phases for patients undergoing stereotactic treatment of primary renal cell carcinoma. VMAT plans were developed from the end-inhale (VMATinh) and the end-exhale (VMATexh) phases of the breathing cycle as well as a VMAT plan and 3-dimensional conformal radiation therapy plan based on an internal target volume (ITV) (VMATitv). An additional VMAT plan was created by giving the respective gated VMAT plan a 50% weighting and summing the inhale and exhale plans together to create a summed gated plan. Dose to organs at risk (OARs) as well as comparison of intermediate and low-dose conformity was evaluated. There was no difference in the volume of healthy tissue receiving the prescribed dose for the planned target volume (PTV) (CI100%) for all the VMAT plans; however, the mean volume of healthy tissue receiving 50% of the prescribed dose for the PTV (CI50%) values were 4.7 (± 0.2), 4.6 (± 0.2), and 4.7 (± 0.6) for the VMATitv, VMATinh, and VMATexh plans, respectively. The VMAT plans based on the exhale and inhale breathing phases showed a 4.8% and 2.4% reduction in dose to 30 cm{sup 3} of the small bowel, respectively, compared with that of the ITV-based VMAT plan. The summed gated VMAT plans showed a 6.2% reduction in dose to 30 cm{sup 3} of the small bowel compared with that of the VMAT plans based on the ITV. Additionally, when compared with the inhale and the exhale VMAT plans, a 4% and 1.5%, respectively, reduction was observed. Gating VMAT was able to reduce the amount of prescribed, intermediate, and integral dose to healthy tissue when compared with VMAT plans based on an ITV. When summing the inhale and exhale plans together, dose to healthy tissue and OARs was optimized. However, gating VMAT plans would take longer to treat and is a factor that needs to be considered.

  17. Synthesis, biological investigation, calf thymus DNA binding and docking studies of the sulfonyl hydrazides and their derivatives

    NASA Astrophysics Data System (ADS)

    Murtaza, Shahzad; Shamim, Saima; Kousar, Naghmana; Tahir, Muhammad Nawaz; Sirajuddin, Muhammad; Rana, Usman Ali

    2016-03-01

    The present study describes the syntheses and biological investigations of sulfonyl hydrazides and their novel derivatives. The detailed investigations involved the characterization of the newly synthesized compounds using FTIR, NMR, mass spectrometry and by single crystal X-Ray diffraction (XRD) analysis techniques. The binding tendencies of these compounds with CT-DNA (calf thymus DNA) have been explored by electronic absorption (UV) spectroscopy and viscosity measurement. The binding constant (K) and Gibb's free energy (ΔG) values were also calculated accordingly. In addition, we also investigated the biological activities such as antioxidant, antibacterial, enzyme inhibition and DNA interactions. The antioxidant activity was assayed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity, while antibacterial activity was investigated against four bacterial strains (viz. Escherichia coli, Crynibacteria bovius, Staphylococcus auras and Bacillus antherasis) by employing the common disc diffusion method. Enzyme inhibition activity of the synthesized compounds was examined against butyrylcholinestrase. The results of enzyme inhibition activity and the DNA binding interaction studies were also collected through molecular docking program using computational analysis. Our study reveals that the newly synthesized compounds possess moderate to good biological activities.

  18. Feasibility Study of Ex Ovo Chick Chorioallantoic Artery Model for Investigating Pulsatile Variation of Arterial Geometry

    PubMed Central

    Nam, Kweon-Ho; Kim, Juho; Ra, Gicheol; Lee, Chong Hyun; Paeng, Dong-Guk

    2015-01-01

    Despite considerable research efforts on the relationship between arterial geometry and cardiovascular pathology, information is lacking on the pulsatile geometrical variation caused by arterial distensibility and cardiomotility because of the lack of suitable in vivo experimental models and the methodological difficulties in examining the arterial dynamics. We aimed to investigate the feasibility of using a chick embryo system as an experimental model for basic research on the pulsatile variation of arterial geometry. Optical microscope video images of various arterial shapes in chick chorioallantoic circulation were recorded from different locations and different embryo samples. The high optical transparency of the chorioallantoic membrane (CAM) allowed clear observation of tiny vessels and their movements. Systolic and diastolic changes in arterial geometry were visualized by detecting the wall boundaries from binary images. Several to hundreds of microns of wall displacement variations were recognized during a pulsatile cycle. The spatial maps of the wall motion harmonics and magnitude ratio of harmonic components were obtained by analyzing the temporal brightness variation at each pixel in sequential grayscale images using spectral analysis techniques. The local variations in the spectral characteristics of the arterial wall motion were reflected well in the analysis results. In addition, mapping the phase angle of the fundamental frequency identified the regional variations in the wall motion directivity and phase shift. Regional variations in wall motion phase angle and fundamental-to-second harmonic ratio were remarkable near the bifurcation area. In summary, wall motion in various arterial geometry including straight, curved and bifurcated shapes was well observed in the CAM artery model, and their local and cyclic variations could be characterized by Fourier and wavelet transforms of the acquired video images. The CAM artery model with the spectral

  19. Feasibility Study of Ex Ovo Chick Chorioallantoic Artery Model for Investigating Pulsatile Variation of Arterial Geometry.

    PubMed

    Nam, Kweon-Ho; Kim, Juho; Ra, Gicheol; Lee, Chong Hyun; Paeng, Dong-Guk

    2015-01-01

    Despite considerable research efforts on the relationship between arterial geometry and cardiovascular pathology, information is lacking on the pulsatile geometrical variation caused by arterial distensibility and cardiomotility because of the lack of suitable in vivo experimental models and the methodological difficulties in examining the arterial dynamics. We aimed to investigate the feasibility of using a chick embryo system as an experimental model for basic research on the pulsatile variation of arterial geometry. Optical microscope video images of various arterial shapes in chick chorioallantoic circulation were recorded from different locations and different embryo samples. The high optical transparency of the chorioallantoic membrane (CAM) allowed clear observation of tiny vessels and their movements. Systolic and diastolic changes in arterial geometry were visualized by detecting the wall boundaries from binary images. Several to hundreds of microns of wall displacement variations were recognized during a pulsatile cycle. The spatial maps of the wall motion harmonics and magnitude ratio of harmonic components were obtained by analyzing the temporal brightness variation at each pixel in sequential grayscale images using spectral analysis techniques. The local variations in the spectral characteristics of the arterial wall motion were reflected well in the analysis results. In addition, mapping the phase angle of the fundamental frequency identified the regional variations in the wall motion directivity and phase shift. Regional variations in wall motion phase angle and fundamental-to-second harmonic ratio were remarkable near the bifurcation area. In summary, wall motion in various arterial geometry including straight, curved and bifurcated shapes was well observed in the CAM artery model, and their local and cyclic variations could be characterized by Fourier and wavelet transforms of the acquired video images. The CAM artery model with the spectral

  20. Investigating the dopaminergic synapse in vivo. I. Molecular imaging studies in humans.

    PubMed

    Nikolaus, Susanne; Antke, Christina; Kley, Konstantin; Poeppel, Thorsten D; Hautzel, Hubertus; Schmidt, Daniela; Müller, Hans-Wilhelm

    2007-01-01

    Dopaminergic synaptic function may be assessed either at the presynaptic terminal or at the postsynaptic binding sites using molecular in vivo imaging methods. Apart from the density of binding sites, parameters such as alterations in dopamine synthesis, dopamine storage or dopamine release can be quantified either by application of specific radiotracers or by assessing the competition between the exogenous radioligand and endogenous dopamine. Investigations of humans in both clinical and experimental settings have yielded evidence that disturbances of dopaminergic function may be associated with numerous neurological and psychiatric conditions, among which are movement disorders, schizophrenia, attention-deficit hyperactivity disorder, depression and drug abuse. This article gives an overview of those studies, which so far have been performed on dopaminergic neurotransmission in humans using in vivo imaging methods. We focus on disease-related deficiencies within the functional entity of the dopaminergic synapse. Taken together, in vivo findings yield evidence of presynaptic dysfunctions in Parkinson's disease with decreases in striatal dopamine synthesis, dopamine storage, dopamine release and dopamine transporter binding. In contrast, 'Parkinson plus' syndromes (multiple system atrophy, progressive supranuclear palsy, corticobasal degeneration, dementia with Lewy bodies) are characterized by both pre- and postsynaptic deficiencies with reductions in striatal dopamine synthesis, dopamine storage, dopamine release, and dopamine transporter, as well as D, and D, receptor binding. In patients with Huntington's disease, postsynaptic dysfunctions with reductions of striatal D1 and D2 receptor binding have become apparent, whereas attention-deficit/ hyperactivity disorder is mainly characterized by presynaptic deficits with increases in dopamine transporter binding. Interestingly, findings are also consistent with respect to drug abuse: cocaine, amphetamine

  1. Integrating Multiple Subsurface Exploration Technologies in Slope Hydrogeologic Investigation: A Case Study in Taiwan

    NASA Astrophysics Data System (ADS)

    Lo, H.-C.; Hsu, S.-M.; Jeng, D.-I.; Ku, C.-Y.

    2009-04-01

    Taiwan is an island located at a tectonically active collision zone between the Eurasian Plate and the Pacific Plate. Also, the island is in the subtropical climate region with frequent typhoon events that are always accompanied by intense rainfalls within a short period of time. These seismic and climatic elements frequently trigger, directly or indirectly, natural disasters such as landslides on the island with casualties and property damages. Prompted by the urge for minimizing the detrimental effects of such natural disasters, Taiwan government has initiated and funded a series of investigations and studies aimed at better understanding the causes of the natural disasters that may lead to the formulation of more effective disaster contingency plans and possibly some forecasts system. The hydrogeology of a landslide site can help unveil the detention condition of storm water entering the aquifer system of the slope as well as its groundwater condition which, in turn, plays a critical role in slope stability. In this study, a hydrogeologic investigation employing a series of subsurface exploration technologies was conducted at an active landslide site in the vicinity of Hwa Yuan Village in northern Taiwan. The site, which covers an area of approximately 0.14 km2 (35 acres) and generally ranges between 25 to 36 degree in slope, was initially investigated with ground resistivity image profiling (RIP) and electrical logging in order to determine the lithology and possibly the water-bearing capacity of the geologic units beneath the slope surface. Subsequently, both acoustic and optical borehole loggings were then applied to identify potentially significant fracture features at depth and their hydrogeologic implications. In addition, flowmeter loggings and hydraulic packer tests were conducted to further characterize the hydrogeologic system of the site and quantitatively determine the hydraulic properties of major hydrogeologic units. According to the ground

  2. Five-year follow-up of patients with early stage breast cancer after a randomized study comparing additional treatment with viscum album (L.) extract to chemotherapy alone.

    PubMed

    Tröger, Wilfried; Zdrale, Zdravko; Stanković, Nikola; Matijašević, Miodrag

    2012-01-01

    Additional therapy with extracts of Viscum album [L.] (VaL) increases the quality of life of patients suffering from early stage breast cancer during chemotherapy. In the current study patients received chemotherapy, consisting of six cycles of cyclophosphamide, anthracycline, and 5-Fluoro-Uracil (CAF). Two groups also received one of two VaL extracts differing in their preparation as subcutaneous injection three times per week. A control group received CAF with no additional therapy. Six of 28 patients in one of the VaL groups and eight of 29 patients in the control group developed relapse or metastasis within 5 years. Subgroup analysis for hormone- and radiotherapy also showed no difference between groups. Additional VaL therapy during chemotherapy of early stage breast cancer patients appears not to influence the frequency of relapse or metastasis within 5 years. PMID:23150723

  3. Five-Year Follow-Up of Patients with Early Stage Breast Cancer After a Randomized Study Comparing Additional Treatment with Viscum Album (L.) Extract to Chemotherapy Alone

    PubMed Central

    Tröger, Wilfried; Ždrale, Zdravko; Stanković, Nikola; Matijašević, Miodrag

    2012-01-01

    Additional therapy with extracts of Viscum album [L.] (VaL) increases the quality of life of patients suffering from early stage breast cancer during chemotherapy. In the current study patients received chemotherapy, consisting of six cycles of cyclophosphamide, anthracycline, and 5-Fluoro-Uracil (CAF). Two groups also received one of two VaL extracts differing in their preparation as subcutaneous injection three times per week. A control group received CAF with no additional therapy. Six of 28 patients in one of the VaL groups and eight of 29 patients in the control group developed relapse or metastasis within 5 years. Subgroup analysis for hormone- and radiotherapy also showed no difference between groups. Additional VaL therapy during chemotherapy of early stage breast cancer patients appears not to influence the frequency of relapse or metastasis within 5 years. PMID:23150723

  4. Prospective study investigating transplacental transmission of equine piroplasmosis in thoroughbred foals in Trinidad.

    PubMed

    Sant, Candice; d'Abadie, Roger; Pargass, Indira; Basu, Asoke K; Asgarali, Zinora; Charles, Roxanne A; Georges, Karla C

    2016-08-15

    Equine piroplasmosis caused by Theileria equi and Babesia caballi is endemic in Trinidad and Tobago. Transmission occurs by ticks of the family Ixodidae. T. equi can also be transmitted transplacentally; however transplacental transmission of B. caballi is unknown. This study aims to investigate transplacental transmission of equine piroplasmosis from thoroughbred mares naturally infected via the tick vector. Whole blood and serum samples were collected from 117 mares in the fifth month of pregnancy. Blood samples were also collected from each of their foals (89 in total) within the first 36h of birth. Additionally, all foals were observed for clinical signs within 30days post - partum. All samples were examined microscopically for intra-erythrocytic piroplasms. Serum ELISA tests and PCR analysis on whole blood were performed to determine the presence of T. equi and B. caballi. Thirty-four (30.6%) mares and 14 (15.7%) of their foals were seropositive for T. equi. Twenty-seven (24.3%) mares were positive for T. equi by conventional (c) PCR. Real time (q) PCR analysis based on the ema - 1 gene revealed that seven (8%) foals were positive for T. equi. Eighty-nine (76.1%) mares and 38 (42.7%) foals were seropositive for B. caballi. Four (3.4%) mares were positive for B. caballi by cPCR. Three out of the four cPCR positive mares either had resorptions, or stillbirths for that pregnancy. From this study, there is strong evidence that transplacental transmission of B. caballi can occur leading to foetal losses. Six foals (7%) were positive for B. caballi by qPCR. Of these six, four were born to B. caballi seropositive mares. In this study a foal born of a T. equi seropositive mare was 55.7 times more likely to be serologically positive for T. equi than a foal born to a T. equi seronegative mare. Similarly a foal born of a B. caballi seropositive mare was 39.4 times more likely to be serologically positive for B. caballi than a foal born to a mare that was serologically

  5. Should the Dead Sea Be Sustainable?: Investigating Environmental Issues Using a Case Study

    ERIC Educational Resources Information Center

    Saunders, Cheston Andrew

    2016-01-01

    Many students leave the environmental science classroom with misconceptions centered on the availability of natural resources such as water. This article presents a case study where students assume the roles of various stakeholders and articulate their position on whether or not to pipe water from the Red Sea to the Dead Sea. Additionally,…

  6. An Exploratory Investigation of Online Forum Mediated Collaborative Learning of Speech Writing: A Case Study

    ERIC Educational Resources Information Center

    Lata, Pushp; Luhach, Suman

    2014-01-01

    Learning Management Systems (LMS) are being integrated in the curriculum by many educational institutions to extend teaching and learning beyond classroom. This paper is based on a case study exploring the integration of LMS Nalanda created on Moodle in Effective Public Speaking (EPS) classroom to give students an additional platform to practice,…

  7. Active mineral additives of sapropel ashes

    NASA Astrophysics Data System (ADS)

    Khomich, V. A.; Danilina, E. V.; Krivonos, O. I.; Plaksin, G. V.

    2015-01-01

    The goal of the presented research is to establish a scientific rational for the possibility of sapropel ashes usage as an active mineral additive. The research included the study of producing active mineral additives from sapropels by their thermal treatment at 850900 °C and afterpowdering, the investigation of the properties of paste matrix with an ash additive, and the study of the ash influence on the cement bonding agent. Thermogravimetric analysis and X-ray investigations allowed us to establish that while burning, organic substances are removed, clay minerals are dehydrated and their structure is broken. Sapropel ashes chemical composition was determined. An amorphous ash constituent is mainly formed from silica of the mineral sapropel part and alumosilicagels resulted from clay minerals decomposition. Properties of PC 400 and PC 500A0 sparopel ash additives were studied. Adding ashes containing Glenium plasticizer to the cement increases paste matrix strength and considerably reduces its water absorption. X-ray phase analysis data shows changes in the phase composition of the paste matrix with an ash additive. Ash additives produce a pozzolanic effect on the cement bonding agent. Besides, an ash additive due to the alumosilicagels content causes transformation from unstable calcium aluminate forms to the stable ones.

  8. WILCOX COUNTY, ALABAMA--A STUDY OF SOCIAL, ECONOMIC, AND EDUCATIONAL BANKRUPTCY. REPORT OF AN INVESTIGATION.

    ERIC Educational Resources Information Center

    BROADUS, JAMES; AND OTHERS

    THE REQUEST FOR THIS INVESTIGATION BY THE SPECIAL COMMITTEE OF THE NATIONAL EDUCATION ASSOCIATION COMMISSION ON PROFESSIONAL RIGHTS AND RESPONSIBILITIES RESULTED FROM THE FIRING OF NINE NEGRO TEACHERS IN WILCOX COUNTY. THE STUDY ITSELF IS MORE INCLUSIVE, INCORPORATING THE FINDINGS AND CONCLUSIONS OF SEPARATE STUDIES IN POVERTY, SCHOOL FINANCE,…

  9. Investigating Trainee Music Teachers' Beliefs on Musical Abilities and Learning: A Quantitative Study

    ERIC Educational Resources Information Center

    Biasutti, Michele

    2010-01-01

    This paper reports a study investigating trainee teachers' beliefs about music abilities and learning. The study employed two questionnaires: the "Music abilities beliefs questionnaire" (MABQ) and the "Music learning beliefs questionnaire" (MLBQ) which were specially designed to reveal the beliefs of trainee teachers of primary and secondary…

  10. Summer Study: A Two Part Investigation of the Impact of Exposure to Schooling on Achievement Growth.

    ERIC Educational Resources Information Center

    David, Jane Lisa

    This thesis is composed of two studies which look at the impact of exposure to schooling on achievement growth of children. Both use data from the National Follow Through Evaluation. The first study investigates the hypothesis that the difference in achievement growth between poor and non-poor children is greater during the summer months than…

  11. Mineral resources of the Sheep Mountain Wilderness study area and the Cucamonga Wilderness and additions, Los Angeles and San Bernardino counties, California

    USGS Publications Warehouse

    Evans, James G.; Pankraatz, Leroy; Ridenour, James; Schmauch, Steven W.; Zilka, Nicholas T.

    1977-01-01

    A mineral survey of the Sheep Mountain Wilderness study area and Cucamonga Wilderness area and additions by the U.S. Geological Survey and Bureau of Mines in 1975 covered about 66,500 acres (26,500 ha) of the San Bernardino and Angeles National Forests in southern California. The two study areas are separated by San Antonio Canyon. The mineral resource potential was evaluated through geological, geochemical, and geophysical studies by the Geological Survey and through evaluation of mines and prospects by the Bureau of Mines.

  12. Functional mapping of left parietal areas involved in simple addition and multiplication. A single-case study of qualitative analysis of errors.

    PubMed

    Della Puppa, Alessandro; De Pellegrin, Serena; Salillas, Elena; Grego, Alberto; Lazzarini, Anna; Vallesi, Antonino; Saladini, Marina; Semenza, Carlo

    2015-09-01

    All electrostimulation studies on arithmetic have so far solely reported general errors. Nonetheless, a classification of the errors during stimulation can inform us about underlying arithmetic processes. The present electrostimulation study was performed in a case of left parietal glioma. The patient's erroneous responses suggested that calculation was mainly applied for addition and a combination of retrieval and calculation was mainly applied for multiplication. The findings of the present single-case study encourage follow up with further data collection with the same paradigm. PMID:24646158

  13. Lab-scale impact test to investigate the pipe-soil interaction and comparative study to evaluate structural responses

    NASA Astrophysics Data System (ADS)

    Ryu, Dong-Man; Lee, Chi-Seung; Choi, Kwang-Ho; Koo, Bon-Yong; Song, Joon-Kyu; Kim, Myung-Hyun; Lee, Jae-Myung

    2015-07-01

    This study examined the dynamic response of a subsea pipeline under an impact load to determine the effect of the seabed soil. A laboratory-scale soil-based pipeline impact test was carried out to investigate the pipeline deformation/strain as well as the interaction with the soil-pipeline. In addition, an impact test was simulated using the finite element technique, and the calculated strain was compared with the experimental results. During the simulation, the pipeline was described based on an elasto-plastic analysis, and the soil was modeled using the Mohr-Coulomb failure criterion. The results obtained were compared with ASME D31.8, and the differences between the analysis results and the rules were specifically investigated. Modified ASME formulae were proposed to calculate the precise structural behavior of a subsea pipeline under an impact load when considering sand- and clay-based seabed soils.

  14. Electrophilic addition of astatine

    SciTech Connect

    Norseev, Yu.V.; Vasaros, L.; Nhan, D.D.; Huan, N.K.

    1988-03-01

    It has been shown for the first time that astatine is capable of undergoing addition reactions to unsaturated hydrocarbons. A new compound of astatine, viz., ethylene astatohydrin, has been obtained, and its retention numbers of squalane, Apiezon, and tricresyl phosphate have been found. The influence of various factors on the formation of ethylene astatohydrin has been studied. It has been concluded on the basis of the results obtained that the univalent cations of astatine in an acidic medium is protonated hypoastatous acid.

  15. Radionuclide disequilibria studies for investigating the integrity of potential nuclear waste disposal sites: subseabed studies.

    SciTech Connect

    Laul, J.C.; Thomas, C.W.; Petersen, M.R.; Perkins, R.W.

    1981-09-01

    This study of subseabed sediments indicates that natural radionuclides can be employed to define past long-term migration rates and thereby evaluate the integrity of potential disposal sites in ocean sediments. The study revealed the following conclusions: (1) the sedimentation rate of both the long and short cores collected in the North Pacific is 2.5 mm/1000 yr or 2.5 m/m.yr in the upper 3 meters; (2) the sedimentation rate has been rather constant over the last one million years; and (3) slow diffusive processes dominate within the sediment. Reworking of the sediment by physical processes or organisms is not observed.

  16. Power Analysis for Population-Based Longitudinal Studies Investigating Gene-Environment Interactions in Chronic Diseases: A Simulation Study

    PubMed Central

    Ma, Jinhui; Thabane, Lehana; Beyene, Joseph; Raina, Parminder

    2016-01-01

    Conventional methods for sample size calculation for population-based longitudinal studies tend to overestimate the statistical power by overlooking important determinants of the required sample size, such as the measurement errors and unmeasured etiological determinants, etc. In contrast, a simulation-based sample size calculation, if designed properly, allows these determinants to be taken into account and offers flexibility in accommodating complex study design features. The Canadian Longitudinal Study on Aging (CLSA) is a Canada-wide, 20-year follow-up study of 30,000 people between the ages of 45 and 85 years, with in-depth information collected every 3 years. A simulation study, based on an illness-death model, was conducted to: (1) investigate the statistical power profile of the CLSA to detect the effect of environmental and genetic risk factors, and their interaction on age-related chronic diseases; and (2) explore the design alternatives and implementation strategies for increasing the statistical power of population-based longitudinal studies in general. The results showed that the statistical power to identify the effect of environmental and genetic risk exposures, and their interaction on a disease was boosted when: (1) the prevalence of the risk exposures increased; (2) the disease of interest is relatively common in the population; and (3) risk exposures were measured accurately. In addition, the frequency of data collection every three years in the CLSA led to a slightly lower statistical power compared to the design assuming that participants underwent health monitoring continuously. The CLSA had sufficient power to detect a small (1

  17. A School-Based Study on Situational Interest of Investigative Study in Senior Physics

    ERIC Educational Resources Information Center

    Leung, Yat-yin

    2015-01-01

    This paper reports the findings from the interview data of a research aiming at studying how to trigger students' situational interest in physics and its implications on learning and teaching in the New Senior Secondary (NSS) physics curriculum. 49 students from a boys' school were invited to write one to three learning experiences in physics that…

  18. Effect of Ag addition on the thermal characteristics and structural evolution of Ag-Cu-Ni ternary alloy nanoclusters: Atomistic simulation study

    NASA Astrophysics Data System (ADS)

    Subbaraman, Ram; Sankaranarayanan, Subramanian K. R. S.

    2011-08-01

    Atomic-scale compositional variation in Ag contents across Ag-Cu-Ni alloy upon being subjected to repeated annealing cycles is shown to result in significant differences in the structure and the thermal stability of ternary alloy nanoclusters. Molecular dynamics (MD) simulations employing quantum Sutton-Chen potentials were used to investigate the effect of Ag addition on the thermal characteristics of Ag-Cu-Ni ternary alloy nanoclusters of 4-nm diameter. The initial configurations were generated using Monte Carlo simulations and comprise surface-segregated structures with the lowest surface energy component, Ag, occupying low coordination sites such as corners, edges, and faces. A compositional oscillation between the Cu and Ni atoms was observed for layers beneath the surface which transitions into a bulk alloy composition at the core. We find that the Cu-Ni binary alloys on being subjected to annealing schedules demonstrated an increase in thermal stability, as indicated by the increase in melting points. The annealed configurations of the Ag-Cu-Ni ternary alloy, on the other hand, showed a nonmonotonic behavior. For Ag compositions less than 20%, we observe an initial increase in melting point followed by a decrease in the third cycle. For higher Ag compositions (>20%), we observe a decrease in melting point with annealing; the rate of decrease is strongly correlated to the Ag composition in the alloy. Cu-Ni nanoclusters having 50% Cu showed a transition from an initial icosahedral to a cuboctahedron-like structure whereas Ag-rich Ag-Cu-Ni ternary alloys showed a transition from icosahedral to an amorphous structure. Compositional analysis based on radial distribution functions and density profiles indicate that these transitions were dependent on the distribution of the alloying elements in the nanocluster. Calculated root-mean-square displacements and diffusion coefficients indicate that the rate of mixing of Ag increases with Ag content in the Ag

  19. Changes in acral blood flux under local application of ropivacaine and lidocaine with and without an adrenaline additive: a double-blind, randomized, placebo-controlled study.

    PubMed

    Häfner, Hans-Martin; Schmid, Ute; Moehrle, Matthias; Strölin, Anke; Breuninger, Helmut

    2008-01-01

    Vascular effects of local anesthetics are especially important in dermatological surgery. In particular, adequate perfusion must be ensured in order to offset surgical manipulations during surgical interventions at the acra. However, the use of adrenaline additives appears fraught with problems when anesthesia affects the terminal vascular system, particularly during interventions at the fingers, toes, penis, outer ears, and tip of the nose. We studied skin blood flux at the fingerpads via laser Doppler flowmetry over the course of 24 hours in a prospective, double-blind, randomized, placebo-controlled study with 20 vascularly healthy test persons following Oberst's-method anesthetic blocks. In each case, 6 ml ropivacaine (7.5 mg/ml) (A), lidocaine 1% without an additive (B), and lidocaine 1% with an adrenaline additive (1:200,000) (C) was used respectively as a verum. Isotonic saline solution was injected as a placebo (D). Measurements were carried out with the aid of a computer simultaneously at D II and D IV on both hands. Administration of (A) led to increased blood flux (+155.2%); of (B) initially to a decrease of 27%; of (C) to a reduction of 55% which was reversible after 40 minutes and of (D) to no change.(A) resulted in sustained vasodilatation which was still demonstrable after 24 h. (B) had notably less vasodilative effect, although comparison with (D) clearly showed that (B) is indeed vasodilative. (C) resulted in only a passing decrease in perfusion; this was no longer measurable when checked after 6 and 24 h. This transient inadequacy of blood flux also appeared after administration of (D). These tests show that adrenaline additive in local anesthesia does not decrease blood flow more than 55% for a period of 16 min. Following these results an adrenaline additive can be safely used for anesthetic blocks at the acra in healthy persons. PMID:18334782

  20. Siloxane containing addition polyimides

    NASA Technical Reports Server (NTRS)

    Maudgal, S.; St. Clair, T. L.

    1984-01-01

    Addition polyimide oligomers have been synthesized from bis(gamma-aminopropyl) tetramethyldisiloxane and 3, 3', 4, 4'-benzophenonetetracarboxylic dianhydride using a variety of latent crosslinking groups as endcappers. The prepolymers were isolated and characterized for solubility (in amide, chlorinated and ether solvents), melt flow and cure properties. The most promising systems, maleimide and acetylene terminated prepolymers, were selected for detailed study. Graphite cloth reinforced composites were prepared and properties compared with those of graphite/Kerimid 601, a commercially available bismaleimide. Mixtures of the maleimide terminated system with Kerimid 601, in varying proportions, were also studied.