Ex-vacuo nuclear reaction analysis of deuterium

International Nuclear Information System (INIS)

Lee, S.R.; Doyle, B.L.

1989-01-01

A novel technique for performing in-air d( 3 He, p) nuclear reaction analysis of deuterium using external 3 He ion beams ranging in energy from 0.3-2.0 MeV is presented. Variable on-target beam energies for the depth profiling of deuterium are obtained by varying the transmission distance of the external 3 He beam in air. The ex-vacuo nuclear reaction analysis (XNRA) apparatus is described, and unique aspects and limitations of in-air depth profiling of deuterium using the d( 3 He, p) reaction are discussed. Example analyses where XNRA has been used for the multidimensional measurement of deuterium in fusion reactor components are presented in order to illustrate the advantages of XNRA for deuterium. These advantages include nondestructive analysis of large targets, efficient depth profiling via variable air gap energy tuning, and rapid analysis of numerous samples in the absence of vacuum cycling. (orig.)

Comparative Analysis of Clinical Samples Showing Weak Serum Reaction on AutoVue System Causing ABO Blood Typing Discrepancies.

Science.gov (United States)

Jo, Su Yeon; Lee, Ju Mi; Kim, Hye Lim; Sin, Kyeong Hwa; Lee, Hyeon Ji; Chang, Chulhun Ludgerus; Kim, Hyung Hoi

2017-03-01

ABO blood typing in pre-transfusion testing is a major component of the high workload in blood banks that therefore requires automation. We often experienced discrepant results from an automated system, especially weak serum reactions. We evaluated the discrepant results by the reference manual method to confirm ABO blood typing. In total, 13,113 blood samples were tested with the AutoVue system; all samples were run in parallel with the reference manual method according to the laboratory protocol. The AutoVue system confirmed ABO blood typing of 12,816 samples (97.7%), and these results were concordant with those of the manual method. The remaining 297 samples (2.3%) showed discrepant results in the AutoVue system and were confirmed by the manual method. The discrepant results involved weak serum reactions (serum reactions, samples from patients who had received stem cell transplants, ABO subgroups, and specific system error messages. Among the 98 samples showing ≤1+ reaction grade in the AutoVue system, 70 samples (71.4%) showed a normal serum reaction (≥2+ reaction grade) with the manual method, and 28 samples (28.6%) showed weak serum reaction in both methods. ABO blood tying of 97.7% samples could be confirmed by the AutoVue system and a small proportion (2.3%) needed to be re-evaluated by the manual method. Samples with a 2+ reaction grade in serum typing do not need to be evaluated manually, while those with ≤1+ reaction grade do.

Herpes simplex encephalitis: MRI findings in two cases confirmed by polymerase chain reaction assay

Energy Technology Data Exchange (ETDEWEB)

Lee, J.W.; Kim, I.O.; Kim, W.S.; Yeon, K.M. [Dept. of Radiology and the Institute of Radiation Medicine, Seoul National University Hospital, Seoul (Korea); Lee, H.-J.; Hwang, Y.S. [Dept. of Paediatrics, Seoul National University College of Medicine, Seoul (Korea)

2001-09-01

Herpes simplex virus (HSV) type I causes a fulminant necrotising meningoencephalitis distinguished from other encephalitides by its focal and often haemorrhagic nature. Specific antiviral therapy with acyclovir can significantly improve the prognosis. We present MRI findings of two cases of herpes simplex encephalitis (HSE) confirmed by PCR analysis, focusing on the serial changes after acyclovir therapy: gyral swelling, high signal intensity on T2-weighted images in the subfrontal region, temporal lobe and insula in the initial stage, then regional extension with enhancement and haemorrhage despite appropriate acyclovir therapy, and finally encephalomalacia and brain atrophy. (orig.)

Herpes simplex encephalitis: MRI findings in two cases confirmed by polymerase chain reaction assay

International Nuclear Information System (INIS)

Lee, J.W.; Kim, I.O.; Kim, W.S.; Yeon, K.M.; Lee, H.-J.; Hwang, Y.S.

2001-01-01

Herpes simplex virus (HSV) type I causes a fulminant necrotising meningoencephalitis distinguished from other encephalitides by its focal and often haemorrhagic nature. Specific antiviral therapy with acyclovir can significantly improve the prognosis. We present MRI findings of two cases of herpes simplex encephalitis (HSE) confirmed by PCR analysis, focusing on the serial changes after acyclovir therapy: gyral swelling, high signal intensity on T2-weighted images in the subfrontal region, temporal lobe and insula in the initial stage, then regional extension with enhancement and haemorrhage despite appropriate acyclovir therapy, and finally encephalomalacia and brain atrophy. (orig.)

Safety confirmation study of TRUEX solvent by accelerating rate calorimeter (ARC)

International Nuclear Information System (INIS)

Sato, Yoshihiko; Hirumachi, Suguru; Takeda, Shinso; Kanazawa, Yoshito; Sasaya, Shinji

1999-02-01

In order to confirm the engineering safety on the TRUEX solvent (mixed solvent of CMPO/TBP/n-dodecane) for separating the transuranics from high-level activity liquid waste in advanced nuclear fuel recycling technological R and D, thermal behavior and pressure behavior in heating PUREX solvent (mixed solvent of 30% TBP-n-dodecane), TRUEX solvent and in the exothermic reaction of TRUEX solvent etc. and nitric acid in sealed adiabatic system which was severer condition than actual plant were measured by using accelerating rate calorimeter (ARC). The Arrhenius parameters (activation energy and frequency factor) which are necessary for the evaluation of reaction rate was examined from the measurement data in ARC. Analytical method and analysis condition of reaction products were examined in order to clarify chemical form of reaction products in exothermic reaction between solvent and nitric acid in ARC, and the qualitative evaluation was carried out. Main results are shown in the following. 1) TBP, CMPO, n-dodecane and 10 M nitric acid hardly exothermed in the simple substance. 2) On the solvent phase after the solvent contacted with 10 M nitric acid and the equilibrium has been attained (single-phase sample), the heat quantity per unit sample weight of the TRUEX solvent tended to be bigger than that of the PUREX solvent when heat quantity was evaluated in ARC. However, on the mixed sample of solvent and 10 M nitric acid enclosed in a sample container simultaneously (two phase system sample), the heat quantity per unit solvent weight was almost equivalent for PUREX solvent and TRUEX solvent. 3) The kinetic analysis was carried out, and on the TBP-10 M nitric acid single-phase sample, the activation energy of the reaction was evaluated to be 118 kJ/mol. Its activation energy was approximately equal to 112 kJ/mol by Nichols. The reaction rate constant was calculated, and it was shown that reaction rate constants of PUREX solvent-10 M nitric acid single-phase sample and

A confirmative clinimetric analysis of the 36-item Family Assessment Device.

Science.gov (United States)

Timmerby, Nina; Cosci, Fiammetta; Watson, Maggie; Csillag, Claudio; Schmitt, Florence; Steck, Barbara; Bech, Per; Thastum, Mikael

2018-02-07

The Family Assessment Device (FAD) is a 60-item questionnaire widely used to evaluate self-reported family functioning. However, the factor structure as well as the number of items has been questioned. A shorter and more user-friendly version of the original FAD-scale, the 36-item FAD, has therefore previously been proposed, based on findings in a nonclinical population of adults. We aimed in this study to evaluate the brief 36-item version of the FAD in a clinical population. Data from a European multinational study, examining factors associated with levels of family functioning in adult cancer patients' families, were used. Both healthy and ill parents completed the 60-item version FAD. The psychometric analyses conducted were Principal Component Analysis and Mokken-analysis. A total of 564 participants were included. Based on the psychometric analysis we confirmed that the 36-item version of the FAD has robust psychometric properties and can be used in clinical populations. The present analysis confirmed that the 36-item version of the FAD (18 items assessing 'well-being' and 18 items assessing 'dysfunctional' family function) is a brief scale where the summed total score is a valid measure of the dimensions of family functioning. This shorter version of the FAD is, in accordance with the concept of 'measurement-based care', an easy to use scale that could be considered when the aim is to evaluate self-reported family functioning.

Development of LEAP-JET code for sodium-water reaction analysis. Validation by sodium-water reaction tests (SWAT-1R)

International Nuclear Information System (INIS)

Seino, Hiroshi; Hamada, Hirotsugu

2004-03-01

The sodium-water reaction event in an FBR steam generator (SG) has influence on the safety, economical efficiency, etc. of the plant, so that the selection of design base leak (DBL) of the SG is considered as one of the important matters. The clarification of the sodium-water reaction phenomenon and the development of an analysis model are necessary to estimate the sodium-water reaction event with high accuracy and rationality in selecting the DBL. The reaction jet model is pointed out as a part of the necessary improvements to evaluate the overheating tube rupture of large SGs, since the behavior of overheating tube rupture is largely affected by the reaction jet conditions outside the tube. Therefore, LEAP-JET has been developed as an analysis code for the simulation of sodium-water reactions. This document shows the validation of the LEAP-JET code by the Sodium-Water Reaction Test (SWAT-1R). The following results have been obtained: (1) The reaction rate constant, K, is estimated at between 0.001≤K≤0.1 from the LEAP-JET analysis of the SWAT-1R data. (2) The analytical results on the high-temperature region and the behaviors of reaction consumption (Na, H 2 O) and products (H 2 , NaOH, Na 2 O) are considered to be physically reasonable. (3) The LEAP-JET analysis shows the tendency of overestimation in the maximum temperature and temperature distribution of the reaction jet. (4) In the LEAP-JET analysis, the numerical calculation becomes unstably, especially in the mesh containing quite small sodium mass. Therefore, it is necessary to modify the computational algorism to stabilize it and obtain the optimum value of K in sodium-water reactions. (author)

An Attributional Analysis of Reactions to Negative Emotions.

Science.gov (United States)

Karasawa, Kaori

1995-01-01

Three studies examined observers' attributions and reactions to negative emotional displays, as well as expressers' expectations about others' reactions. Analysis revealed that people attribute others' negative emotions equally to situational factors and dispositions, whereas their own emotions are attributed to the situation more than to…

The first experimental confirmation of the fractional kinetics containing the complex-power-law exponents: Dielectric measurements of polymerization reactions

Science.gov (United States)

Nigmatullin, R. R.; Arbuzov, A. A.; Salehli, F.; Giz, A.; Bayrak, I.; Catalgil-Giz, H.

2007-01-01

For the first time we achieved incontestable evidence that the real process of dielectric relaxation during the polymerization reaction of polyvinylpyrrolidone (PVP) is described in terms of the fractional kinetic equations containing complex-power-law exponents. The possibility of the existence of the fractional kinetics containing non-integer complex-power-law exponents follows from the general theory of dielectric relaxation that has been suggested recently by one of the authors (R.R.N). Based on the physical/geometrical meaning of the fractional integral with complex exponents there is a possibility to develop a general theory of dielectric relaxation based on the self-similar (fractal) character of the reduced (averaged) microprocesses that take place in the mesoscale region. This theory contains some essential predictions related to existence of the non-integer power-law kinetics and the results of this paper can be considered as the first confirmation of existence of the kinetic phenomena that are described by fractional derivatives with complex-power-law exponents. We want to stress here that with the help of a new complex fitting function for the complex permittivity it becomes possible to describe the whole process for real and imaginary parts simultaneously throughout the admissible frequency range (30 Hz-13 MHz). The fitting parameters obtained for the complex permittivity function for three temperatures (70, 90 and 110 °C) confirm in general the picture of reaction that was known qualitatively before. They also reveal some new features, which improve the interpretation of the whole polymerization process. We hope that these first results obtained in the paper will serve as a good stimulus for other researches to find the traces of the existence of new fractional kinetics in other relaxation processes unrelated to the dielectric relaxation. These results should lead to the reconsideration and generalization of irreversibility and kinetic phenomena that

Performance Confirmation Plan

International Nuclear Information System (INIS)

Lindner, E.N.

2000-01-01

As described, the purpose of the Performance Confirmation Plan is to specify monitoring, testing, and analysis activities for evaluating the accuracy and adequacy of the information used to determine that performance objectives for postclosure will be met. This plan defines a number of specific performance confirmation activities and associated test concepts in support of the MGR that will be implemented to fulfill this purpose. In doing so, the plan defines an approach to identify key factors and processes, predict performance, establish tolerances and test criteria, collect data (through monitoring, testing, and experiments), analyze these data, and recommend appropriate action. The process of defining which factors to address under performance confirmation incorporates input from several areas. In all cases, key performance confirmation factors are those factors which are: (1) important to safety, (2) measurable and predictable, and (3) relevant to the program (i.e., a factor that is affected by construction, emplacement, or is a time-dependent variable). For the present version of the plan, performance confirmation factors important to safety are identified using the principal factors from the RSS (CRWMS M and O 2000a) (which is derived from TSPA analyses) together with other available performance assessment analyses. With this basis, key performance confirmation factors have been identified, and test concepts and test descriptions have been developed in the plan. Other activities are also incorporated into the performance confirmation program outside of these key factors. Additional activities and tests have been incorporated when they are prescribed by requirements and regulations or are necessary to address data needs and model validation requirements relevant to postclosure safety. These other activities have been included with identified factors to construct the overall performance confirmation program

Performance Confirmation Plan

International Nuclear Information System (INIS)

Lindner, E.N.

2000-01-01

As described, the purpose of the Performance Confirmation Plan is to specify monitoring, testing, and analysis activities for evaluating the accuracy and adequacy of the information used to determine that performance objectives for postclosure will be met. This plan defines a number of specific performance confirmation activities and associated test concepts in support of the MGR that will be implemented to fulfill this purpose. In doing so, the plan defines an approach to identify key factors and processes, predict performance, establish tolerances and test criteria, collect data (through monitoring, testing, and experiments), analyze these data, and recommend appropriate action. The process of defining which factors to address under performance confirmation incorporates input from several areas. In all cases, key performance confirmation factors are those factors which are: (1) important to safety, (2) measurable and predictable, and (3) relevant to the program (i.e., a factor that i s affected by construction, emplacement, or is a time-dependent variable). For the present version of the plan, performance confirmation factors important to safety are identified using the principal factors from the RSS (CRWMS M and O 2000a) (which is derived from TSPA analyses) together with other available performance assessment analyses. With this basis, key performance confirmation factors have been identified, and test concepts and test descriptions have been developed in the plan. Other activities are also incorporated into the performance confirmation program outside of these key factors. Additional activities and tests have been incorporated when they are prescribed by requirements and regulations or are necessary to address data needs and model validation requirements relevant to postclosure safety. These other activities have been included with identified factors to construct the overall performance confirmation program

Reactions of acid bisphosphonodithioates with nitriles

International Nuclear Information System (INIS)

Kutyrev, G.A.; Korolev, O.S.; Yarkova, E.G.; Cherkasov, R.A.; Pudovik, A.N.

1986-01-01

The reactions of acid bisphosphonodithioates with aceto- and benzo-nitriles go with the intermediate formation of a 1:1 adduct, which breaks down into a thioamide and a cyclic trithiopyrophosphonate. The stability of the latter falls with the lengthening of the carbon chain in the original thiophosphorus reactant. A detailed analysis of IR and NMR spectra is given to confirm these results

Specifications for surface reaction analysis apparatus

International Nuclear Information System (INIS)

Teraoka, Yuden; Yoshigoe, Akitaka

2001-03-01

A surface reaction analysis apparatus was installed at the JAERI soft x-ray beamline in the SPring-8 as an experimental end-station for the study of surface chemistry. The apparatus is devoted to the study concerning the influence of translational kinetic energy of incident molecules to chemical reactions on solid surfaces with gas molecules. In order to achieve the research purpose, reactive molecular scattering experiments and photoemission spectroscopic measurements using synchrotron radiation are performed in that apparatus via a supersonic molecular beam generator, an electron energy analyzer and a quadrupole mass analyzer. The detail specifications for the apparatus are described in this report. (author)

Numerical Analysis of Microwave Heating on Saponification Reaction

Science.gov (United States)

Huang, Kama; Jia, Kun

2005-01-01

Currently, microwave is widely used in chemical industry to accelerate chemical reactions. Saponification reaction has important applications in industry; some research results have shown that microwave heating can significantly accelerate the reaction [1]. But so far, no efficient method has been reported for the analysis of the heating process and design of an efficient reactor powered by microwave. In this paper, we present a method to study the microwave heating process on saponification reaction, where the reactant in a test tube is considered as a mixture of dilute solution. According to the preliminary measurement results, the effective permittivity of the mixture is approximately the permittivity of water, but the conductivity, which could change with the reaction, is derived from the reaction equation (RE). The electromagnetic field equation and reaction equation are coupled by the conductivity. Following that, the whole heating processes, which is described by Maxwell's equations, the reaction equation and heat transport equation (HTE), is analyzed by finite difference time domain (FDTD) method. The temperature rising in the test tube are measured and compared with the computational results. Good agreement can be seen between the measured and calculated results.

Analysis of diffusivity of the oscillating reaction components in a microreactor system

Directory of Open Access Journals (Sweden)

Martina Šafranko

2017-01-01

Full Text Available When performing oscillating reactions, periodical changes in the concentrations of reactants, intermediaries, and products take place. Due to the mentioned periodical changes of the concentrations, the information about the diffusivity of the components included into oscillating reactions is very important for the control of the oscillating reactions. Non-linear dynamics makes oscillating reactions very interesting for analysis in different reactor systems. In this paper, the analysis of diffusivity of the oscillating reaction components was performed in a microreactor, with the aim of identifying the limiting component. The geometry of the microreactor microchannel and a well defined flow profile ensure optimal conditions for the diffusion phenomena analysis, because diffusion profiles in a microreactor depend only on the residence time. In this paper, the analysis of diffusivity of the oscillating reaction components was performed in a microreactor equipped with 2 Y-shape inlets and 2 Y-shape outlets, with active volume of V = 4 μL at different residence times.

Use of palivizumab and infection control measures to control an outbreak of respiratory syncytial virus in a neonatal intensive care unit confirmed by real-time polymerase chain reaction.

LENUS (Irish Health Repository)

O'Connell, K

2011-04-01

Respiratory syncytial virus (RSV) is a potentially life-threatening infection in premature infants. We report an outbreak involving four infants in the neonatal intensive care unit (NICU) of our hospital that occurred in February 2010. RSV A infection was confirmed by real-time polymerase chain reaction. Palivizumab was administered to all infants in the NICU. There were no additional symptomatic cases and repeat RSV surveillance confirmed that there was no further cross-transmission within the unit. The outbreak highlighted the infection control challenge of very high bed occupancy in the unit and the usefulness of molecular methods in facilitating detection and management.

PERFORMANCE CONFIRMATION IN-SITU INSTRUMENTATION

International Nuclear Information System (INIS)

N.T. Raczka

2000-01-01

The purpose of this document is to identify and analyze the types of in-situ instruments and methods that could be used in support of the data acquisition portion of the Performance Confirmation (PC) program at the potential nuclear waste repository at Yucca Mountain. The PC program will require geomechanical , geophysical, thermal, and hydrologic instrumentation of several kinds. This analysis is being prepared to document the technical issues associated with each type of measurement during the PC period. This analysis utilizes the ''Performance Confirmation Input Criteria'' (CRWMS M andO 1999a) as its starting point. The scope of this analysis is primarily on the period after the start of waste package emplacement and before permanent closure of the repository, a period lasting between 15 and 300 years after last package emplacement (Stroupe 2000, Attachment 1, p. 1). The primary objectives of this analysis are to: (1) Review the design criteria as presented in the ''Performance Confirmation Input Criteria'' (CRWMS M andO 1999a). The scope of this analysis will be limited to the instrumentation related to parameters that require continuous monitoring of the conditions underground. (2) Preliminary identification and listing of the data requirements and parameters as related to the current repository layout in support of PC monitoring. (3) Preliminary identification of methods and instrumentation for the acquisition of the required data. Although the ''Performance Confirmation Input Criteria'' (CRWMS M andO 1999a) defines a broad range of data that must be obtained from a variety of methods, the focus of this analysis is on instrumentation related to the performance of the rock mass and the formation of water in the repository environment, that is obtainable from in-situ observation, testing, and monitoring

Structural parameter identifiability analysis for dynamic reaction networks

DEFF Research Database (Denmark)

Davidescu, Florin Paul; Jørgensen, Sten Bay

2008-01-01

method based on Lie derivatives. The proposed systematic two phase methodology is illustrated on a mass action based model for an enzymatically catalyzed reaction pathway network where only a limited set of variables is measured. The methodology clearly pinpoints the structurally identifiable parameters...... where for a given set of measured variables it is desirable to investigate which parameters may be estimated prior to spending computational effort on the actual estimation. This contribution addresses the structural parameter identifiability problem for the typical case of reaction network models....... The proposed analysis is performed in two phases. The first phase determines the structurally identifiable reaction rates based on reaction network stoichiometry. The second phase assesses the structural parameter identifiability of the specific kinetic rate expressions using a generating series expansion...

Isothermal reaction calorimetry as a tool for kinetic analysis

International Nuclear Information System (INIS)

Zogg, Andreas; Stoessel, Francis; Fischer, Ulrich; Hungerbuehler, Konrad

2004-01-01

Reaction calorimetry has found widespread application for thermal and kinetic analysis of chemical reactions in the context of thermal process safety as well as process development. This paper reviews the most important reaction calorimetric principles (heat-flow, heat-balance, power-compensation, and Peltier principle) and their applications in commercial or scientific devices. The discussion focuses on the different dynamic behavior of the main calorimetric principles during an isothermal reaction measurement. Examples of available reaction calorimeters are further compared considering their detection limit, time constant as well as temperature range. In a second part, different evaluation methods for the isothermally measured calorimetric data are reviewed and discussed. The methods will be compared, focusing especially on the fact that reaction calorimetric data always contains additional informations not directly related to the actual chemical reaction such as heat of mixing, heat of phase-transfer/change processes or simple measurement errors. Depending on the evaluation method applied such disturbances have a significant influence on the calculated reaction enthalpies or rate constants

Verification of cold nuclear fusion reaction, (1)

International Nuclear Information System (INIS)

Yoshida, Zenko; Aratono, Yasuyuki; Hirabayashi, Takakuni

1991-01-01

Can cold nuclear fusion reaction occur as is expected? If it occurs, what extent is its reaction probability? At present after 2 years elapsed since its beginning, the clear solution of these questions is not yet obtained. In many reaction systems employing different means, the experiments to confirm the cold nuclear fusion reaction have been attempted. In order to confirm that the nuclear fusion reaction of deuterium mutually has occurred, the neutrons, He-3, protons, tritium or generated heat, which were formed by the reaction and released from the system, are measured. Since it is considered that the frequency of the occurrence at normal temperature of the reaction is very low, it is necessary to select the most suitable method upon evaluating the limit of detection peculiar to the measuring methods. The methods of measuring neutrons, protons, gamma ray and generated heat, and the reaction systems by electrolytic process and dry process are explained. The detection of plural kinds of the reaction products and the confirmation of synchronism of signals are important. (K.I.)

Confirmation of identity and detection limit in neutron activation analysis

International Nuclear Information System (INIS)

Yustina Tri Handayani; Slamet Wiyuniati; Tulisna

2010-01-01

Neutron Activation Analysis (NAA) based on neutron capture by nuclides. Of the various possibilities of radionuclides that occur, radionuclides and gamma radiation which provides the identity of the element were analyzed and the best sensitivity should be determined. Confirmation for elements in sediment samples was done theoretically and experimentally. The result of confirmation shows that Al, V, Cr K, Na, Ca and Zn were analyzed based on radionuclides of Al-28, V-52, Cr-51 , K-42, Na-24, Ca-48, Zn-65. Elements of Mg, Mn, Fe, Co were analyzed based on radionuclides of Mg-27, Mn-56, Fe-59, Co-60 through peak which the highest value of combined probability of radiation emission and efficiency. Cu can be analyzed through Cu-64 or Cu-66, but the second is more sensitive. Detection limit is determined at a certain measurement conditions carried out by a laboratory. Detection limit in the NAA is determined based on the Compton continue area by Curie method. The detection limit of Al, V, Ca, Mg, Mn, As, K, Na, Mg, Ce, Co, Cr, Fe, La, Sc, and Zn in sediment samples are 240, 27, 4750, 2600, 21, 3.3 , 75, 1.4, 1.8, 0.5, 2.7, 29, 1, 0.05, and 37 ppm. Analysis of Cu in sediments which concentrations of 98.6 ppm, Cu-66 is not detected. Tests using pure standard solutions of Cu obtained detection limit of 0.12 µg, or 7.9 ppm in samples of 15 mg. In general, the detection limit obtained was higher than the detection limit of the reference, it was caused by the differences in the sample matrix and analytical conditions. (author)

Analysis of acoustic data from UK sodium/water reaction test facilities

International Nuclear Information System (INIS)

Rowley, R.; Mcknight, J.A.; Airey, J.

1990-01-01

This paper describes acoustic measurements made during a number of sodium/water reaction experiments in the UK. The tests have included water and steam injections through both realistic (fatigue crack) defects and machined orifices and have covered a range of experimental conditions including those appropriate to the inlet and outlet regions of the EFR steam generators. Injection rates were typically in the range 0.1 to 30 g/s. Where possible, gas injections were also included in the test programme for comparison, since it is anticipated that a practical SGU acoustic leak detection system would include a facility for gas injections to allow system calibration, and to confirm transmission properties within the SGU. The test sections were instrumented with accelerometers on waveguides and in some cases included an under-sodium microphone situated about 300mm above the reaction zone. Tape recordings were made during the tests and used for detailed analysis off-line, although an audible output from one of the acoustic channels was used to monitor the progress of the injections and provide information for the rig operators. A comparison of the signal amplitudes measured during the experiments with typical reactor background noise was made and an estimate of the detection sensitivity of an acoustic monitoring system was deduced. 3 refs, 5 figs, 1 tab

Substance abusers' personality disorders and staff members' emotional reactions

Directory of Open Access Journals (Sweden)

Hesse Morten

2008-04-01

Full Text Available Abstract Background Previous research has indicated that aggressive behaviour and DSM-IV cluster B personality disorders (PD may be associated with professionals' emotional reactions to clients, and that cluster C PD may be associated with positive emotional reactions. Methods Staff members recruited from workshops completed a self-report inventory of emotional reactions to patients, the Feeling Word Checklist-58, and substance abusers completed a self-report of DSM-IV personality disorder, the DSM-IV and ICD-10 Personality Disorder Questionnaire. Correlational analysis and multiple regression analysis was used to assess the associations between personality disorders and emotional reations. Results Cluster B disorder features were associated with feeling distance to patients, and cluster C disorder features were associated with feeling helpful towards patients. Cluster A disorders had no significant impact on emotional reactions. Conclusion The findings confirm clinical experiences that personality disorder features in patients with substance abuse have an impact on staff members reactions to them. These reactions should be considered in supervision of staff, and in treatment models for patients with co-morbid personality disorders and substance abuse.

Nonimmediate hypersensitivity reactions to iodinated contrast media.

Science.gov (United States)

Gómez, Enrique; Ariza, Adriana; Blanca-López, Natalia; Torres, Maria J

2013-08-01

To provide a detailed analysis of the latest findings on the mechanisms underlying the nonimmediate reactions to iodinated contrast media and comment on the recent advances in diagnosis, focusing on the roles of the skin test, drug provocation test (DPT), and lymphocyte transformation test (LTT). Several studies have reported new findings supporting an important role for T-lymphocytes in the nonimmediate reactions to iodinated contrast media. The LTT has been used as an in-vitro tool for diagnosis, but with variable results. However, the inclusion of autologous monocyte-derived dendritic cells as professional antigen-presenting cells has improved the sensitivity of this test. Regarding in-vivo diagnosis, although skin testing has been routine, it has now been shown that its sensitivity and negative predictive value are low. Recent studies have demonstrated that the DPT is a well tolerated and useful procedure that is necessary to confirm the diagnosis of nonimmediate hypersensitivity reactions to iodinated contrast media. Nonimmediate reactions to contrast media are usually T-cell mediated. Diagnosis is based on skin testing, although its sensitivity and negative predictive value are not optimal. Consequently, drug provocation testing is often needed to confirm the diagnosis and also to seek alternative contrast media that can be tolerated.

Nonlinear analysis of a reaction-diffusion system: Amplitude equations

Energy Technology Data Exchange (ETDEWEB)

Zemskov, E. P., E-mail: zemskov@ccas.ru [Russian Academy of Sciences, Dorodnicyn Computing Center (Russian Federation)

2012-10-15

A reaction-diffusion system with a nonlinear diffusion term is considered. Based on nonlinear analysis, the amplitude equations are obtained in the cases of the Hopf and Turing instabilities in the system. Turing pattern-forming regions in the parameter space are determined for supercritical and subcritical instabilities in a two-component reaction-diffusion system.

Dose Volume Histogram analysis for rectum and urethral reaction of prostate cancer

International Nuclear Information System (INIS)

Yanagi, Takeshi; Tsuji, Hiroshi; Kamada, Tadashi; Tsujii, Hirohiko

2005-01-01

The aim of this study is to evaluate the clinically relevant parameters for rectum and urethral reaction using DVH (dose volume histogram) in carbon ion radiotherapy of prostate cancer. In this year, we studied the urinary reaction mainly. 35 patients with prostate cancer were treated with carbon ion beams between June 1995 and December 1997. The applied dose was escalated from 54.0 GyE to 72.0 GyE in fixed 20 fractions. Clinical urinary reaction and rectum reaction were reviewed using Radiation Therapy Oncology Group (RTOG) scoring system for acute reactions, RTOG/European Organization for Research and Treatment of Cancer (EORTC) scoring system for late reactions. Taking the ROI (region of interest) for DVH of urethra, we used surrogate one that was derived from the observation of MR images. 35 patients were analyzed for acute urinary reaction and 34 for late urinary reaction in the study of this year. DVH analysis suggested difference among the grades for acute and late reactions. These analysis appears to be a useful tool for predicting the urinary reactions. (author)

Primary ovary choriocarcinoma: individual DNA polymorphic analysis as a strategy to confirm diagnosis and treatment

Directory of Open Access Journals (Sweden)

Fernando Nalesso

2013-04-01

Full Text Available Primary choriocarcinoma of the ovary is rare. Furthermore, this tumor can arise from gestational tissue or pure germ cells of the ovary, with the latter resulting in non-gestational choriocarcinoma. While the clinical characteristics and histology of both tumor types are identical, differentiation of these tumors is necessary for effective treatment. One strategy for the differentiation of these tumors types is to assay for the presence of paternal DNA. Accordingly, in the present case, a patient with primary choriocarcinoma of the ovary with a non-gestational origin was confirmed by DNA analysis. The patient subsequently exhibited an excellent response to chemotherapy, and following surgery, achieved complete remission. A pathological analysis of surgical specimens further confirmed the absence of tumor.

Reaction mechanism of reductive decomposition of FGD gypsum with anthracite

International Nuclear Information System (INIS)

Zheng, Da; Lu, Hailin; Sun, Xiuyun; Liu, Xiaodong; Han, Weiqing; Wang, Lianjun

2013-01-01

Highlights: • The reaction mechanism was different if the molar ratio of C/CaSO 4 was different. • The yield of CaO rises with an increase in temperature. • The optimal ratio of C/CaSO 4 = 1.2:1. • The decomposition process is mainly apparent solid–solid reaction with liquid-phase involved. - Abstract: The process of decomposition reaction between flue gas desulfurization (FGD) gypsum and anthracite is complex, which depends on the reaction conditions and atmosphere. In this study, thermogravimetric analysis with Fourier transform infrared spectroscopy (TGA-FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and the experiment in a tubular reactor were used to characterize the decomposition reaction in a nitrogen atmosphere under different conditions. The reaction mechanism analysis showed that the decomposition reaction process and mechanism were different when the molar proportion of C/CaSO 4 was changed. The experiment results showed that appropriate increase in the C/CaSO 4 proportion and higher temperatures were suitable for the formation of the main production of CaO, which can help us to understand the solid state reaction mechanism better. Via kinetic analysis of the reaction between anthracite and FGD gypsum under the optimal molar ratio of C/CaSO 4 , the mechanism model of the reaction was confirmed and the decomposition process was a two-step reaction which was in accordance with apparent solid–solid reaction

High throughput reaction screening using desorption electrospray ionization mass spectrometry.

Science.gov (United States)

Wleklinski, Michael; Loren, Bradley P; Ferreira, Christina R; Jaman, Zinia; Avramova, Larisa; Sobreira, Tiago J P; Thompson, David H; Cooks, R Graham

2018-02-14

We report the high throughput analysis of reaction mixture arrays using methods and data handling routines that were originally developed for biological tissue imaging. Desorption electrospray ionization (DESI) mass spectrometry (MS) is applied in a continuous on-line process at rates that approach 10 4 reactions per h at area densities of up to 1 spot per mm 2 (6144 spots per standard microtiter plate) with the sprayer moving at ca. 10 4 microns per s. Data are analyzed automatically by MS using in-house software to create ion images of selected reagents and products as intensity plots in standard array format. Amine alkylation reactions were used to optimize the system performance on PTFE membrane substrates using methanol as the DESI spray/analysis solvent. Reaction times can be screening of processes like N -alkylation and Suzuki coupling reactions as reported herein. Products and by-products were confirmed by on-line MS/MS upon rescanning of the array.

Physiological environment induce quick response - slow exhaustion reactions

Directory of Open Access Journals (Sweden)

Noriko eHiroi

2011-09-01

Full Text Available In vivo environments are highly crowded and inhomogeneous, which may affect reaction processes in cells. In this study we examined the effects of intracellular crowding and an inhomogeneity on the behavior of in vivo reactions by calculating the spectral dimension (ds, which can be translated into the reaction rate function. We compared estimates of anomaly parameters obtained from Fluorescence Correlation Spectroscopy (FCS data with fractal dimensions derived from Transmission Electron Microscopy (TEM image analysis. FCS analysis indicated that the anomalous property was linked to physiological structure. Subsequent TEM analysis provided an in vivo illustration; soluble molecules likely percolate between intracellular clusters, which are constructed in a self-organizing manner. We estimated a cytoplasmic spectral dimension ds to be 1.39 ± 0.084. This result suggests that in vivo reactions initially run faster than the same reactions in a homogeneous space; this conclusion is consistent with the anomalous character indicated by FCS analysis. We further showed that these results were compatible with our Monte-Carlo simulation in which the anomalous behavior of mobile molecules correlates with the intracellular environment, leading to description as a percolation cluster, as demonstrated using TEM analysis. We confirmed by the simulation that the above-mentioned in vivo like properties are different from those of homogeneously concentrated environments. Additionally, simulation results indicated that crowding level of an environment might affect diffusion rate of reactant. Such knowledge of the spatial information enables us to construct realistic models for in vivo diffusion and reaction systems.

Development of blow down and sodium-water reaction jet analysis codes-Validation by sodium-water reaction tests (SWAT-1R)

International Nuclear Information System (INIS)

Hiroshi Seino; Akikazu Kurihara; Isao Ono; Koji Jitsu

2005-01-01

Blow down analysis code (LEAP-BLOW) and sodium-water reaction jet analysis code (LEAP-JET) have been developed in order to improve the evaluation method on sodium-water reaction event in the steam generator (SG) of a sodium cooled fast breeder reactor (FBR). The validation analyses by these two codes were carried out using the data of Sodium-Water Reaction Test (SWAT-1R). The following main results have been obtained through this validation: (1) The calculational results by LEAP-BLOW such as internal pressure and water flow rate show good agreement with the results of the SWAT- 1R test. (2) The LEAP-JET code can qualitatively simulate the behavior of sodium-water reaction. However, it is found that the code has tendency to overestimate the maximum temperature of the reaction jet. (authors)

Large-leak sodium-water reaction analysis for steam generators

International Nuclear Information System (INIS)

Sakano, K.; Shindo, Y.; Hori, M.

1975-01-01

The guillotine rupture of 4 tubes is assumed as a design basis regarding the large-leak sodium-water reaction in the system of the MONJU steam generator. Three kinds of analyses were performed with the view to showing the integrity of the steam generator system on the reaction. The first one is the analysis of the initial pressure spike, assuming the initial guillotine rupture of 1 tube. The analysis was performed by utilizing one-dimensional sphere-cylinder model code SWAC-7 and two-dimensional axisymmetric code PISCES 2DL. The second one is the analysis of the secondary peak pressure and its propagation in the system, assuming the instantaneous guillotine rupture of 4 tubes. The third one is the analysis of the dynamic deformation of the steam generator shell. The integrity of the steam generator system was shown by the analyses. (author)

Large-leak sodium-water reaction analysis for steam generators

Energy Technology Data Exchange (ETDEWEB)

Sakano, K; Shindo, Y; Hori, M

1975-07-01

The guillotine rupture of 4 tubes is assumed as a design basis regarding the large-leak sodium-water reaction in the system of the MONJU steam generator. Three kinds of analyses were performed with the view to showing the integrity of the steam generator system on the reaction. The first one is the analysis of the initial pressure spike, assuming the initial guillotine rupture of 1 tube. The analysis was performed by utilizing one-dimensional sphere-cylinder model code SWAC-7 and two-dimensional axisymmetric code PISCES 2DL. The second one is the analysis of the secondary peak pressure and its propagation in the system, assuming the instantaneous guillotine rupture of 4 tubes. The third one is the analysis of the dynamic deformation of the steam generator shell. The integrity of the steam generator system was shown by the analyses. (author)

Outcome of polymerase chain reaction (PCR) analysis in 100 suspected cases of infectious uveitis.

Science.gov (United States)

Kharel Sitaula, Ranju; Janani, M K; Madhavan, H N; Biswas, Jyotirmay

2018-01-10

Polymerase chain reaction (PCR) analysis is an important tool in the diagnosis of infectious uveitis. A retrospective, interventional study of PCR analysis of ocular fluid in suspected infectious uveitis cases between January 2014 to July 2016 was done. Nested, real-time and broad range PCR was performed for detection of the genome of Mycobacterium tuberculosis, herpes virus family, Chikungunya virus, Toxoplasma gondii, fungus, eubacterium and propionibacterium acne. Total of 100 cases included, mean age was 39.2 ± 15.4 years. Uveitis was unilateral in 82% and granulomatous in 40%. Mean visual acuity at the initial visit and final visit was 0.73 logMar and 0.63 logMar respectively. PCR analysis confirmed the clinical diagnosis in 70.1% patients. The sensitivity, specificity, positive predictive value and negative predictive value of PCR analysis was 90.2%, 93.9%, 93.9% and 90.2% respectively. The quantitative value of real-time M. tb. Positive PCR ranged from 32c/ml to 2722 c/ml. PCR assay is an accurate technique with high sensitivity and specificity to diagnose the DNA genome in infectious uveitis.

Redox reaction characteristics of riboflavin: a fluorescence spectroelectrochemical analysis and density functional theory calculation.

Science.gov (United States)

Chen, Wei; Chen, Jie-Jie; Lu, Rui; Qian, Chen; Li, Wen-Wei; Yu, Han-Qing

2014-08-01

Riboflavin (RF), the primary redox active component of flavin, is involved in many redox processes in biogeochemical systems. Despite of its wide distribution and important roles in environmental remediation, its redox behaviors and reaction mechanisms in hydrophobic sites remain unclear yet. In this study, spectroelectrochemical analysis and density functional theory (DFT) calculation were integrated to explore the redox behaviors of RF in dimethyl sulfoxide (DMSO), which was used to create a hydrophobic environment. Specifically, cyclic voltafluorometry (CVF) and derivative cyclic voltafluorometry (DCVF) were employed to track the RF concentration changing profiles. It was found that the reduction contained a series of proton-coupled electron transfers dependent of potential driving force. In addition to the electron transfer-chemical reaction-electron transfer process, a disproportionation (DISP1) process was also identified to be involved in the reduction. The redox potential and free energy of each step obtained from the DFT calculations further confirmed the mechanisms proposed based on the experimental results. The combination of experimental and theoretical approaches yields a deep insight into the characteristics of RF in environmental remediation and better understanding about the proton-coupled electron transfer mechanisms. Copyright © 2014 Elsevier B.V. All rights reserved.

Analysis of transfer reactions: determination of spectroscopic factors

Energy Technology Data Exchange (ETDEWEB)

Keeley, N. [CEA Saclay, Dept. d' Astrophysique, de Physique des Particules de Physique Nucleaire et de l' Instrumentation Associee (DSM/DAPNIA/SPhN), 91- Gif sur Yvette (France); The Andrzej So an Institute for Nuclear Studies, Dept. of Nuclear Reactions, Warsaw (Poland)

2007-07-01

An overview of the most popular models used for the analysis of direct reaction data is given, concentrating on practical aspects. The 4 following models (in order of increasing sophistication): the distorted wave born approximation (DWBA), the adiabatic model, the coupled channels born approximation, and the coupled reaction channels are briefly described. As a concrete example, the C{sup 12}(d,p)C{sup 13} reaction at an incident deuteron energy of 30 MeV is analysed with progressively more physically sophisticated models. The effect of the choice of the reaction model on the spectroscopic information extracted from the data is investigated and other sources of uncertainty in the derived spectroscopic factors are discussed. We have showed that the choice of the reaction model can significantly influence the nuclear structure information, particularly the spectroscopic factors or amplitudes but occasionally also the spin-parity, that we wish to extract from direct reaction data. We have also demonstrated that the DWBA can fail to give a satisfactory description of transfer data but when the tenets of the theory are fulfilled DWBA can work very well and will yield the same results as most sophisticated models. The use of global rather than fitted optical potentials can also lead to important differences in the extracted spectroscopic factors.

[Adverse reaction caused by rabies vaccine in China: a Meta-analysis].

Science.gov (United States)

Zhang, X R; Wu, Z G; Zhang, W S

2017-06-10

Objective: To conduct a Meta-analysis on the rate of adverse reaction related to rabies vaccine, so as to provide reference for rabies vaccine immunization in China. Methods: We electronically searched databases including CNKI, VIP information resource integration service platform, WanFang Data, CBM, PubMed and The Cochrane Library, to collect studies on Chinese people who had received full rabies vaccination and recording all the adverse reactions, from January 2000 to July 2016. Inclusion and exclusion criteria were strictly followed. Meta-analysis for the adverse reaction rate was performed using the R software. Results: A total of 29 related papers had met the inclusion criteria, with no publication bias noticed. A total number of 11 020 cases had adverse reactions, among all the 94 222 respondents, with an incidence of adverse reactions as 1.04 % -47.78 % . The overall incidence rate of adverse reaction was 9.82 % (95 %CI : 7.58 % -12.72 % ). A combined local adverse reaction rate appeared as 12.05 % (95 % CI : 9.26 % -15.69 % ). The systemic adverse reaction rate was 9.06 % (95 %CI : 7.07 % -11.61 % ). The overall adverse reaction rate on aqueous vaccine was 32.39 % (95 %CI : 21.88 % -47.94 % ). Combined adverse reaction rate of freeze dried vaccine appeared as 8.65 % (95 %CI : 4.54 % -16.51 % ). Significant differences were seen between both groups ( P rabies vaccination was higher than the systemic adverse reaction rate. The adverse reaction rate of aqueous rabies vaccine was higher than that of freeze dried rabies vaccine. Our results suggested that the aqueous vaccine should gradually be eliminated.

LC-ESI/MS/MS method for rapid screening and confirmation of 44 exogenous anabolic steroids in human urine.

Science.gov (United States)

Jeon, Byoung Wook; Yoo, Hye Hyun; Jeong, Eun Sook; Kim, Ho Jun; Jin, Changbae; Kim, Dong Hyun; Lee, Jaeick

2011-09-01

A sensitive and rapid method based on liquid chromatography-triple-quadrupole tandem mass spectrometry (LC-MS/MS) with electrospray ionization (ESI) has been developed and validated for the screening and confirmation of 44 exogenous anabolic steroids (29 parent steroids and 15 metabolites) in human urine. The method involves an enzymatic hydrolysis, liquid-liquid extraction, and detection by LC-MS/MS. A triple-quadrupole mass spectrometer was operated in positive ESI mode with selected reaction monitoring (SRM) mode for the screening and product ion scan mode for the confirmation. The protonated molecular ions were used as precursor ions for the SRM analysis and product ion scan. The intraday and interday precisions of the target analytes at concentrations of the minimum required performance levels for the screening were 2-14% and 2-15%, respectively. The limits of detection for the screening and confirmation method were 0.1-10 ng/mL and 0.2-10 ng/mL, respectively, for 44 steroids. This method was successfully applied to analysis of urine samples from suspected anabolic steroid abusers.

Positron annihilation investigation and nuclear reaction analysis of helium and oxygen-implanted zirconia

International Nuclear Information System (INIS)

Grynszpan, R.I.; Saude, S.; Anwand, W.; Brauer, G.

2005-01-01

Since irradiation affects in-service properties of zirconia, we investigated the fluence dependence on production and thermal stability of defects induced by helium and oxygen-ion implantation in single crystals of yttria-fully-stabilized zirconia. In either case, depth profiling by slow positron implantation spectroscopy (SPIS) detects a distribution of vacancy-type defects peaking at 60% of the projected ion range R p . Owing to the saturation of positron-trapping occurring for low fluences, which depends on the ion mass, we could estimate a critical size of clusters ranging from 0.4 to 1.6 nm. The lack of SPIS-evidence of an open-volume excess at R p is explained by the presence of over-pressurized gas bubbles. This assumption is confirmed by Nuclear Reaction Analysis of 3 He concentration profiles, which shows that helium remains partly trapped at R p , even after annealing above 400 o C

Mass spectrometric confirmation criterion for product-ion spectra generated in flow-injection analysis. Environmental application

NARCIS (Netherlands)

Geerdink, R.B.; Niessen, W.M.A.; Brinkman, U.A.T.

2001-01-01

The suitability of a confirmation criterion recently recommended in the Netherlands for gas chromatography with mass spectrometric detection (GC-MS), was evaluated for flow-injection analysis (FIA) with atmospheric pressure chemical ionisation MS-MS detection. The main feature of the criterion is

TRANSIT TIMING OBSERVATIONS FROM KEPLER. II. CONFIRMATION OF TWO MULTIPLANET SYSTEMS VIA A NON-PARAMETRIC CORRELATION ANALYSIS

International Nuclear Information System (INIS)

Ford, Eric B.; Moorhead, Althea V.; Morehead, Robert C.; Fabrycky, Daniel C.; Steffen, Jason H.; Carter, Joshua A.; Fressin, Francois; Holman, Matthew J.; Ragozzine, Darin; Charbonneau, David; Lissauer, Jack J.; Rowe, Jason F.; Borucki, William J.; Bryson, Stephen T.; Burke, Christopher J.; Caldwell, Douglas A.; Welsh, William F.; Allen, Christopher; Batalha, Natalie M.; Buchhave, Lars A.

2012-01-01

We present a new method for confirming transiting planets based on the combination of transit timing variations (TTVs) and dynamical stability. Correlated TTVs provide evidence that the pair of bodies is in the same physical system. Orbital stability provides upper limits for the masses of the transiting companions that are in the planetary regime. This paper describes a non-parametric technique for quantifying the statistical significance of TTVs based on the correlation of two TTV data sets. We apply this method to an analysis of the TTVs of two stars with multiple transiting planet candidates identified by Kepler. We confirm four transiting planets in two multiple-planet systems based on their TTVs and the constraints imposed by dynamical stability. An additional three candidates in these same systems are not confirmed as planets, but are likely to be validated as real planets once further observations and analyses are possible. If all were confirmed, these systems would be near 4:6:9 and 2:4:6:9 period commensurabilities. Our results demonstrate that TTVs provide a powerful tool for confirming transiting planets, including low-mass planets and planets around faint stars for which Doppler follow-up is not practical with existing facilities. Continued Kepler observations will dramatically improve the constraints on the planet masses and orbits and provide sensitivity for detecting additional non-transiting planets. If Kepler observations were extended to eight years, then a similar analysis could likely confirm systems with multiple closely spaced, small transiting planets in or near the habitable zone of solar-type stars.

TRANSIT TIMING OBSERVATIONS FROM KEPLER. II. CONFIRMATION OF TWO MULTIPLANET SYSTEMS VIA A NON-PARAMETRIC CORRELATION ANALYSIS

Energy Technology Data Exchange (ETDEWEB)

Ford, Eric B.; Moorhead, Althea V.; Morehead, Robert C. [Astronomy Department, University of Florida, 211 Bryant Space Sciences Center, Gainesville, FL 32611 (United States); Fabrycky, Daniel C. [UCO/Lick Observatory, University of California, Santa Cruz, CA 95064 (United States); Steffen, Jason H. [Fermilab Center for Particle Astrophysics, P.O. Box 500, MS 127, Batavia, IL 60510 (United States); Carter, Joshua A.; Fressin, Francois; Holman, Matthew J.; Ragozzine, Darin; Charbonneau, David [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Lissauer, Jack J.; Rowe, Jason F.; Borucki, William J.; Bryson, Stephen T.; Burke, Christopher J.; Caldwell, Douglas A. [NASA Ames Research Center, Moffett Field, CA 94035 (United States); Welsh, William F. [Astronomy Department, San Diego State University, San Diego, CA 92182-1221 (United States); Allen, Christopher [Orbital Sciences Corporation/NASA Ames Research Center, Moffett Field, CA 94035 (United States); Batalha, Natalie M. [Department of Physics and Astronomy, San Jose State University, San Jose, CA 95192 (United States); Buchhave, Lars A., E-mail: eford@astro.ufl.edu [Niels Bohr Institute, Copenhagen University, DK-2100 Copenhagen (Denmark); Collaboration: Kepler Science Team; and others

2012-05-10

We present a new method for confirming transiting planets based on the combination of transit timing variations (TTVs) and dynamical stability. Correlated TTVs provide evidence that the pair of bodies is in the same physical system. Orbital stability provides upper limits for the masses of the transiting companions that are in the planetary regime. This paper describes a non-parametric technique for quantifying the statistical significance of TTVs based on the correlation of two TTV data sets. We apply this method to an analysis of the TTVs of two stars with multiple transiting planet candidates identified by Kepler. We confirm four transiting planets in two multiple-planet systems based on their TTVs and the constraints imposed by dynamical stability. An additional three candidates in these same systems are not confirmed as planets, but are likely to be validated as real planets once further observations and analyses are possible. If all were confirmed, these systems would be near 4:6:9 and 2:4:6:9 period commensurabilities. Our results demonstrate that TTVs provide a powerful tool for confirming transiting planets, including low-mass planets and planets around faint stars for which Doppler follow-up is not practical with existing facilities. Continued Kepler observations will dramatically improve the constraints on the planet masses and orbits and provide sensitivity for detecting additional non-transiting planets. If Kepler observations were extended to eight years, then a similar analysis could likely confirm systems with multiple closely spaced, small transiting planets in or near the habitable zone of solar-type stars.

Transit Timing Observations from Kepler: II. Confirmation of Two Multiplanet Systems via a Non-parametric Correlation Analysis

Energy Technology Data Exchange (ETDEWEB)

Ford, Eric B.; /Florida U.; Fabrycky, Daniel C.; /Lick Observ.; Steffen, Jason H.; /Fermilab; Carter, Joshua A.; /Harvard-Smithsonian Ctr. Astrophys.; Fressin, Francois; /Harvard-Smithsonian Ctr. Astrophys.; Holman, Matthew J.; /Harvard-Smithsonian Ctr. Astrophys.; Lissauer, Jack J.; /NASA, Ames; Moorhead, Althea V.; /Florida U.; Morehead, Robert C.; /Florida U.; Ragozzine, Darin; /Harvard-Smithsonian Ctr. Astrophys.; Rowe, Jason F.; /NASA, Ames /SETI Inst., Mtn. View /San Diego State U., Astron. Dept.

2012-01-01

We present a new method for confirming transiting planets based on the combination of transit timing variations (TTVs) and dynamical stability. Correlated TTVs provide evidence that the pair of bodies are in the same physical system. Orbital stability provides upper limits for the masses of the transiting companions that are in the planetary regime. This paper describes a non-parametric technique for quantifying the statistical significance of TTVs based on the correlation of two TTV data sets. We apply this method to an analysis of the transit timing variations of two stars with multiple transiting planet candidates identified by Kepler. We confirm four transiting planets in two multiple planet systems based on their TTVs and the constraints imposed by dynamical stability. An additional three candidates in these same systems are not confirmed as planets, but are likely to be validated as real planets once further observations and analyses are possible. If all were confirmed, these systems would be near 4:6:9 and 2:4:6:9 period commensurabilities. Our results demonstrate that TTVs provide a powerful tool for confirming transiting planets, including low-mass planets and planets around faint stars for which Doppler follow-up is not practical with existing facilities. Continued Kepler observations will dramatically improve the constraints on the planet masses and orbits and provide sensitivity for detecting additional non-transiting planets. If Kepler observations were extended to eight years, then a similar analysis could likely confirm systems with multiple closely spaced, small transiting planets in or near the habitable zone of solar-type stars.

Confirmation of a blocked amino terminus of sulfhydryl oxidase

International Nuclear Information System (INIS)

Janolino, V.G.; Morrison-Rowe, S.J.; Swaisgood, H.E.

1990-01-01

The isolation of sulfhydryl oxidase from bovine milk in a suitably pure form for sequencing was carried out by transient covalent affinity chromatography of diafiltered whey using cysteinylsuccinamidopropyl-glass as matrix. The glutathione-eluted proteins were separated by SDS-PAGE. By radiolabeling the affinity chromatography-purified enzyme with [ 14 C]iodoacetate before subjecting to SDS-PAGE, the sulfhydryl oxidase band was identified, because sulfhydryl oxidase is known to be inactivated by alkylation of one sulfhydryl group per mole. The results confirmed that sulfhydryl oxidase corresponds to the 85 (± 5)-kDa band observed on SDS-PAGE. The protein band corresponding to radiolabeled sulfhydryl oxidase was recovered from SDS-PAGE gels by electrophoretic elution and by electroblotting on polyvinylidene difluoride membrane and subjected to gas phase sequencing. Precautions were taken during electrophoretic elution to prevent reactions that result in N-terminal blocking. Both methods of protein recovery yielded negative results when subjected to sequence analysis indicating that the N-terminus of sulfhydryl oxidase is blocked

Thermodynamically consistent Bayesian analysis of closed biochemical reaction systems

Directory of Open Access Journals (Sweden)

Goutsias John

2010-11-01

Full Text Available Abstract Background Estimating the rate constants of a biochemical reaction system with known stoichiometry from noisy time series measurements of molecular concentrations is an important step for building predictive models of cellular function. Inference techniques currently available in the literature may produce rate constant values that defy necessary constraints imposed by the fundamental laws of thermodynamics. As a result, these techniques may lead to biochemical reaction systems whose concentration dynamics could not possibly occur in nature. Therefore, development of a thermodynamically consistent approach for estimating the rate constants of a biochemical reaction system is highly desirable. Results We introduce a Bayesian analysis approach for computing thermodynamically consistent estimates of the rate constants of a closed biochemical reaction system with known stoichiometry given experimental data. Our method employs an appropriately designed prior probability density function that effectively integrates fundamental biophysical and thermodynamic knowledge into the inference problem. Moreover, it takes into account experimental strategies for collecting informative observations of molecular concentrations through perturbations. The proposed method employs a maximization-expectation-maximization algorithm that provides thermodynamically feasible estimates of the rate constant values and computes appropriate measures of estimation accuracy. We demonstrate various aspects of the proposed method on synthetic data obtained by simulating a subset of a well-known model of the EGF/ERK signaling pathway, and examine its robustness under conditions that violate key assumptions. Software, coded in MATLAB®, which implements all Bayesian analysis techniques discussed in this paper, is available free of charge at http://www.cis.jhu.edu/~goutsias/CSS%20lab/software.html. Conclusions Our approach provides an attractive statistical methodology for

Relation of expansion due to alkali silica reaction to the degree of reaction measured by SEM image analysis

International Nuclear Information System (INIS)

Haha, M. Ben; Gallucci, E.; Guidoum, A.; Scrivener, K.L.

2007-01-01

Scanning Electron Microscopy Image Analysis (SEM-IA) was used to quantify the degree of alkali silica reaction in affected microbars, mortar and concrete prisms. It was found that the degree of reaction gave a unique correlation with the macroscopic expansion for three different aggregates, stored at three temperatures and with two levels of alkali. The relationships found for the concretes and the mortars overlap when normalised by the aggregate content. This relationship seems to be linear up to a critical reaction degree which coincides with crack initiation within the reactive aggregates

Theoretical and experimental studies of N and SF2 reaction

International Nuclear Information System (INIS)

Yu Shuqin; Zhou Xiaoguo

2000-02-01

In this paper, free radical reaction of N+SF 2 induced by dc discharge in N 2 and SF 6 system was examined. Although the NS + (m/z = 46) ion signals were detected, NS + is not the spectral carrier from obtained REMPI spectra analysis. Ab initio quantum calculation shows that NSF is the main product of N + SF 2 . It is confirmed from this calculation that NS + obtained in experiment was produced by multiphoton ionization and dissociation of NSF which is real product of N + SF 2 reaction. (author)

Derivatization reactions in the gas—liquid chromatographic analysis of drugs in biological fluids

NARCIS (Netherlands)

Hulshoff, A.; Lingeman, H.

1984-01-01

Alkylation, acylation, silylation and other derivatization reactions applied to the gas chromatographic analysis of drugs in biological matrices are reviewed. Reaction conditions are discussed in relation to reaction mechanisms. Detector-oriented labelling of drugs, and derivatization with chiral

Carpatizine, a novel bridged oxazine derivative generated by non-enzymatic reactions.

Science.gov (United States)

Fu, Peng; MacMillan, John B

2017-06-27

Carpatizine (1), a new bridged oxazine derivative, was isolated from a marine-derived Streptomyces strain SNE-011. The structure was fully determined by spectroscopic analysis, ECD calculations and chemical methods. A plausible non-enzymatic reaction mechanism from daryamide D leading to carpatizine was presented, which was confirmed by chemical transformation.

Stability Analysis of a Reaction-Diffusion System Modeling Atherogenesis

KAUST Repository

Ibragimov, Akif; Ritter, Laura; Walton, Jay R.

2010-01-01

This paper presents a linear, asymptotic stability analysis for a reaction-diffusionconvection system modeling atherogenesis, the initiation of atherosclerosis, as an inflammatory instability. Motivated by the disease paradigm articulated by Ross

Nuclear reaction analysis of hydrogen in materials: Principals and applications

International Nuclear Information System (INIS)

Lanford, W.A.

1991-01-01

Analysis for hydrogen in materials is difficult by most traditional analytic methods. Because hydrogen has no Auger transitions, no X-ray transitions, does not neutron activate, and does not backscatter ions, it is invisible in analytical methods based on these effects. In addition, since hydrogen is a universal contaminant in vacuum systems, techniques based on mass spectrometry are difficult unless extreme measures are taken to reduce hydrogen backgrounds. Because of this situation, methods have been developed for analyzing for hydrogen in solid materials based on nuclear reactions between bombarding ions and hydrogen atoms (protons) in the samples. The nuclear reaction methods are now practiced at laboratories around the world. The basic principals of nuclear reaction analysis will be briefly presented. This method will be illustrated by applications to problems ranging from basic physics, to geology, to materials science, and to art history and archeology

Analysis by nuclear reactions and activations. A current bibliography

International Nuclear Information System (INIS)

Bujdoso, E.

2001-01-01

A current bibliography based on INIS Atomindex with 78 references on Analysis by nuclear reactions and activations has been prepared for year 1998. References are arranged by first authors' name. (N.T.)

Molecular Confirmation of Salmonella typhimuriumin Poultry from Kathmandu Valley

Directory of Open Access Journals (Sweden)

Sanjeev Kumar Adhikari

2018-05-01

Full Text Available A prevalence study was carried to isolate Salmonella typhimurium from blood (n= 50 and gut samples (n=100 of poultry in Kathmandu valley during early 2016. Salmonella typhimurium bacteria isolated in the selective media were biochemically confirmed based on Bergey’s Manual. Two sets of oligonucleotide primers-the genus specific 16S rRNA and the organism specific invA were employed for molecular level confirmation by the Polymerase Chain Reaction (PCR assay. The amplified fragments in 1% agarose gel observed at 406bp and 285bp, respectively confirmed the isolates to be Salmonella typhimurium. Of 150 samples tested, Salmonella typhimurium were isolated from 49 samples, among which nine were from blood (18% and forty from the gut (40%. The present result indicated an alarmingly high level of Salmonella typhimurium, which can result inzoonotic infection in humans owing to increased contact with poultry and consumption of poultry products in the Kathmandu valley.

The hydroxylation of passive oxide films on X-70 steel by dissolved hydrogen studied by nuclear reaction analysis, Auger electron spectroscopy, X-ray photoelectron spectroscopy and secondary ion mass spectroscopy

International Nuclear Information System (INIS)

Zhang Chunsi; Luo Jingli; Munoz-Paniagua, David; Norton, Peter R.

2006-01-01

Dissolved hydrogen is known to reduce the corrosion resistance of a passive oxide film on iron and its alloys, especially towards pitting corrosion. Electrochemical techniques have been used to show that the passive films are changed by dissolved hydrogen in an alloy substrate, but direct confirmation of the chemical and compositional profiles and changes has been missing. In this paper we report the direct profiling and compositional analysis of the 4 nm passive film on X-70 steel by Auger electron spectroscopy (AES), secondary ion mass spectrometry (SIMS), X-ray photoelectron spectroscopy (XPS) and nuclear reaction analysis (NRA) while hydrogen (deuterium) is charged into the alloy samples from the reverse, unpassivated side. The only route for D to the passive film is therefore by dissolution and diffusion. We show that the original duplex structure of the passive film is converted to a more continuous film containing hydroxyl groups, by reaction with the dissolved hydrogen. This conversion of the oxide ions to hydroxyl groups can lead to more rapid reaction and replacement with (e.g.) Cl - , which is known to enhance pitting. These results are entirely consistent with previous electrochemical studies and provide the first direct confirmation of models on the formation and role of hydroxyl groups derived from these earlier studies

Performance Confirmation Data Acquisition System

International Nuclear Information System (INIS)

D.W. Markman

2000-01-01

The purpose of this analysis is to identify and analyze concepts for the acquisition of data in support of the Performance Confirmation (PC) program at the potential subsurface nuclear waste repository at Yucca Mountain. The scope and primary objectives of this analysis are to: (1) Review the criteria for design as presented in the Performance Confirmation Data Acquisition/Monitoring System Description Document, by way of the Input Transmittal, Performance Confirmation Input Criteria (CRWMS M and O 1999c). (2) Identify and describe existing and potential new trends in data acquisition system software and hardware that would support the PC plan. The data acquisition software and hardware will support the field instruments and equipment that will be installed for the observation and perimeter drift borehole monitoring, and in-situ monitoring within the emplacement drifts. The exhaust air monitoring requirements will be supported by a data communication network interface with the ventilation monitoring system database. (3) Identify the concepts and features that a data acquisition system should have in order to support the PC process and its activities. (4) Based on PC monitoring needs and available technologies, further develop concepts of a potential data acquisition system network in support of the PC program and the Site Recommendation and License Application

Samarium ion exchanged montmorillonite for high temperature cumene cracking reaction

International Nuclear Information System (INIS)

Binitha, N.N.

2009-01-01

Full text: Nano material Montmorillonite clay is cation exchanged with samarium and its catalytic influence in cumene cracking reaction is investigated. Effect of exchange with sodium ions on further exchange with samarium ions is also noted. Acidity measurements are done using TPD of ammonia. The retention of basic structure is proved from FTIR spectra and XRD patterns. Elemental analysis result shows that samarium exchange has occurred, which is responsible for the higher catalytic activity. Surface area and pore volume remains more or less unaffected upon exchange. Thermogravimetric analysis indicates the enhanced thermal stability on exchanging. Cumene cracking reaction is carried out at atmospheric pressure in a fixed bed glass reactor at 673 K. The predominance of Bronsted acidity is confirmed from high selectivity to benzene. (author)

Comparison of a conventional and nested PCR for diagnostic confirmation and genotyping of Orientia tsutsugamushi.

Science.gov (United States)

Janardhanan, Jeshina; Prakash, John Antony Jude; Abraham, Ooriapadickal C; Varghese, George M

2014-05-01

A nested polymerase chain reaction (PCR) targeting the 56-kDa antigen gene is currently the most commonly used molecular technique for confirmation of scrub typhus and genotyping of Orientia tsutsugamushi. In this study, we have compared the commonly used nested PCR (N-PCR) with a single-step conventional PCR (C-PCR) for amplification and genotyping. Eschar samples collected from 24 patients with scrub typhus confirmed by IgM enzyme-linked immunosorbent assay were used for DNA extraction following which amplifications were carried out using nested and C-PCR methods. The amplicons were sequenced and compared to other sequences in the database using BLAST. Conventional PCR showed a high positivity rate of 95.8% compared to the 75% observed using N-PCR. On sequence analysis, the N-PCR amplified region showed more variation among strains than the C-PCR amplified region. The C-PCR, which is more economical, provided faster and better results compared to N-PCR. Copyright © 2014 Elsevier Inc. All rights reserved.

Stability analysis of non-autonomous reaction-diffusion systems: the effects of growing domains

KAUST Repository

Madzvamuse, Anotida; Gaffney, Eamonn A.; Maini, Philip K.

2009-01-01

By using asymptotic theory, we generalise the Turing diffusively-driven instability conditions for reaction-diffusion systems with slow, isotropic domain growth. There are two fundamental biological differences between the Turing conditions on fixed and growing domains, namely: (i) we need not enforce cross nor pure kinetic conditions and (ii) the restriction to activator-inhibitor kinetics to induce pattern formation on a growing biological system is no longer a requirement. Our theoretical findings are confirmed and reinforced by numerical simulations for the special cases of isotropic linear, exponential and logistic growth profiles. In particular we illustrate an example of a reaction-diffusion system which cannot exhibit a diffusively-driven instability on a fixed domain but is unstable in the presence of slow growth. © Springer-Verlag 2009.

Stability analysis of non-autonomous reaction-diffusion systems: the effects of growing domains

KAUST Repository

Madzvamuse, Anotida

2009-08-29

By using asymptotic theory, we generalise the Turing diffusively-driven instability conditions for reaction-diffusion systems with slow, isotropic domain growth. There are two fundamental biological differences between the Turing conditions on fixed and growing domains, namely: (i) we need not enforce cross nor pure kinetic conditions and (ii) the restriction to activator-inhibitor kinetics to induce pattern formation on a growing biological system is no longer a requirement. Our theoretical findings are confirmed and reinforced by numerical simulations for the special cases of isotropic linear, exponential and logistic growth profiles. In particular we illustrate an example of a reaction-diffusion system which cannot exhibit a diffusively-driven instability on a fixed domain but is unstable in the presence of slow growth. © Springer-Verlag 2009.

Theoretical Research on the Mechanism of the Dimerization Reactions of Alkyl Ketene

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Zhiguo Zhang

2013-01-01

Full Text Available A quantum chemical method was employed to investigate the mechanism of dimerization reactions of alkyl ketene. All the geometric configurations of the stationary points on the reactions path were optimized with Gaussian03 employing density functional theory at the B3LYP/6-311G++(d, p level by energy gradient technique. The transition states were also investigated through synchronous transit method, and its reasonability was confirmed by using frequency analysis and intrinsic reaction coordinate analysis. The results can be summed up as follows: according to the frontier orbital theory, the dimerization reaction (3 to generate four-membered carbon cyclic product P3 is forbidden. Two different dimerization processes of alkyl ketene are all concerted but nonsynchronous, taking place through twisted four-membered cyclic transition states. The activation energies were calculated to be 34.54 and 61.73 kJ/mol, respectively for the two ketene dimerization processes. Calculation results satisfactorily explained the experimental facts.

Generic Model-Based Tailor-Made Design and Analysis of Biphasic Reaction Systems

DEFF Research Database (Denmark)

Anantpinijwatna, Amata

systems have a broad range of application, such as the manufacture of petroleum based chemicals, pharmaceuticals, and agro-bio products. Major considerations in the design and analysis of biphasic reaction systems are physical and chemical equilibria, kinetic mechanisms, and reaction rates. The primary...... contribution of this thesis is the development of a systematic modelling framework for the biphasic reaction system. The developed framework consists of three modules describing phase equilibria, reactions and mass transfer, and material balances of such processes. Correlative and predictive thermodynamic......Biphasic reaction systems are composed of immiscible aqueous and organic liquid phases where reactants, products, and catalysts are partitioned. These biphasic conditions point to novel synthesis paths, higher yields, and faster reactions, as well as facilitate product separation. The biphasic...

Recovery Act. Direct Confirmation of Commercial Geothermal Resources in Colorado Using Remote Sensing and On-Site Exploration, Testing, and Analysis

Energy Technology Data Exchange (ETDEWEB)

Foley, Paul [Pagosa Verde LLC, Pagosa Springs, CO (United States); Skeehan, Kirsten [Pagosa Verde LLC, Pagosa Springs, CO (United States); Smith, Jerome [Pagosa Verde LLC, Pagosa Springs, CO (United States); Mink, Roy [Pagosa Verde LLC, Pagosa Springs, CO (United States); Geohydro, Mink [Pagosa Verde LLC, Pagosa Springs, CO (United States)

2016-02-16

Report on the confirmation of Commercial Geothermal Resources in Colorado describing the on site testing and analysis to confirm remote sensing identified potential resources. A series of thermal gradient wells were drilled in the Pagosa Springs region and the data collected is analyzed within.

Can Technical Analysis Signals Detect Price Reactions Around Earnings Announcement?: Evidence from Indonesia

OpenAIRE

Dedhy Sulistiawan; Jogiyanto Hartono

2014-01-01

This study examines whether technical analysis signals can detect price reactions before and after earnings announcement dates in Indonesian stock market. Earnings announcements produce reactions, both before and after the announcements. Informed investors may use private information before earnings announcements (Christophe, Ferri and Angel, 2004; Porter, 1992). Using technical analysis signals, this study expects that retail investors (uninformed investors) can detect preannouncements react...

Multifractal scaling analysis of autopoisoning reactions over a rough surface

International Nuclear Information System (INIS)

Chaudhari, Ajay; Yan, Ching-Cher Sanders; Lee, S.-L.

2003-01-01

Decay type diffusion-limited reactions (DLR) over a rough surface generated by a random deposition model were performed. To study the effect of the decay profile on the reaction probability distribution (RPD), multifractal scaling analysis has been carried out. The dynamics of these autopoisoning reactions are controlled by the two parameters in the decay function, namely, the initial sticking probability (P ini ) of every site and the decay rate (m). The smaller the decay rate, the narrower is the range of α values in the α-f(α) multifractal spectrum. The results are compared with the earlier work of DLR over a surface of diffusion-limited aggregation (DLA). We also considered here the autopoisoning reactions over a smooth surface for comparing our results, which show clearly how the roughness affects the chemical reactions. The q-τ(q) multifractal curves for the smooth surface are linear whereas those for the rough surface are nonlinear. The range of α values in the case of a rough surface is wider than that of the smooth surface

Reaction path analysis of sodium-water reaction phenomena in support of chemical reaction model development

International Nuclear Information System (INIS)

Kikuchi, Shin; Ohshima, Hiroyuki; Hashimoto, Kenro

2011-01-01

Computational study of the sodium-water reaction at the gas (water) - liquid (sodium) interface has been carried out using ab initio (first-principle) method. A possible reaction channel has been identified for the stepwise OH bond dissociations of a single water molecule. The energetics including the binding energy of a water molecule to the sodium surface, the activation energies of the bond cleavages, and the reaction energies, have been evaluated, and the rate constants of the first and second OH bond-breakings have been compared. The results are used as the basis for constructing the chemical reaction model used in a multi-dimensional sodium-water reaction code, SERAPHIM, being developed by JAEA toward the safety assessment of the steam generator (SG) in a sodium-cooled fast reactor (SFR). (author)

Analysis of reaction products formed in the gas phase reaction of E,E-2,4-hexadienal with atmospheric oxidants: Reaction mechanisms and atmospheric implications

Science.gov (United States)

Colmenar, I.; Martin, P.; Cabañas, B.; Salgado, S.; Martinez, E.

2018-03-01

An analysis of reaction products for the reaction of E,E-2,4-hexadienal with chlorine atoms (Cl) and OH and NO3 radicals has been carried out at the first time with the aim of obtaining a better understanding of the tropospheric reactivity of α,β-unsaturated carbonyl compounds. Fourier Transform Infrared (FTIR) spectroscopy and Gas Chromatography-Mass Spectrometry with a Time of Flight detector (GC-TOFMS) were used to carry out the qualitative and/or quantitative analyses. Reaction products in gas and particulate phase were observed from the reactions of E,E-2,4- hexadienal with all oxidants. E/Z-Butenedial and maleic anhydride were the main products identified in gas phase. E-butenedial calculated molar yield ranging from 4 to 10%. A significant amount of multifunctional compounds (chloro and hydroxy carbonyls) was identified. These compounds could be formed in particulate phase explaining the ∼90% of unaccounted carbon in gas phase. The reaction with Cl atoms in the presence of NOx with a long reaction time gave Peroxy Acetyl Nitrate (PAN) as an additional product, which is known for being an important specie in the generation of the photochemical smog. Nitrated compounds were the major organic products from the reaction with the NO3 radical. Based on the identified products, the reaction mechanisms have been proposed. In these mechanisms a double bond addition of the atmospheric oxidant at C4/C5 of E,E-2,4-hexadienal is the first step for tropospheric degradation.

Integrating reaction and analysis: investigation of higher-order reactions by cryogenic trapping

Directory of Open Access Journals (Sweden)

Skrollan Stockinger

2013-09-01

Full Text Available A new approach for the investigation of a higher-order reaction by on-column reaction gas chromatography is presented. The reaction and the analytical separation are combined in a single experiment to investigate the Diels–Alder reaction of benzenediazonium-2-carboxylate as a benzyne precursor with various anthracene derivatives, i.e. anthracene, 9-bromoanthracene, 9-anthracenecarboxaldehyde and 9-anthracenemethanol. To overcome limitations of short reaction contact times at elevated temperatures a novel experimental setup was developed involving a cooling trap to achieve focusing and mixing of the reactants at a defined spot in a fused-silica capillary. This trap functions as a reactor within the separation column in the oven of a gas chromatograph. The reactants are sequentially injected to avoid undefined mixing in the injection port. An experimental protocol was developed with optimized injection intervals and cooling times to achieve sufficient conversions at short reaction times. Reaction products were rapidly identified by mass spectrometric detection. This new approach represents a practical procedure to investigate higher-order reactions at an analytical level and it simultaneously provides valuable information for the optimization of the reaction conditions.

Analysis and characterization of heavy residues produced in 129Xe + natSn reactions between 8 and 25 AMeV

International Nuclear Information System (INIS)

Moisan, J.

2008-06-01

Studies with the INDRA multidetector of the 129 Xe + nat Sn reactions showed the unexpected existence of heavy fragments with a charge as large as Z=70. The charges of Xe and Sn are 54 and 50 respectively. Reactions between nuclei with a charge product greater than 2700 are dominated by deep inelastic collisions. For Xe + Sn the product is exactly 2700. After these observations, 129 Xe + nat Sn reactions at 8, 12, 15, 20 and 25 AMeV have been done. It will then be possible to clarify if the heavy residues are formed by an incomplete fusion, massive transfers occurring in deep inelastic collisions or a very asymmetric fission of a compound system. This work will present experimental results obtained by the analysis of these experiments. We will show that heavy residues are formed with a production cross-section of 10 -2 mb. Angular distributions show that the residues can be produced by an incomplete fusion of the projectile and the target. The study of the products in coincidence with the residues shows that a compound system was formed, followed by a fission producing the residue and a lighter fragment. The comparison with a phenomenological model, HIPSE, confirms that the model is valid at these energies

Shortening Isolation of Patients With Suspected Tuberculosis by Using Polymerase Chain Reaction Analysis

DEFF Research Database (Denmark)

Fløe, Andreas; Hilberg, Ole; Thomsen, Vibeke Østergaard

2015-01-01

Background. Isolation of patients suspected for pulmonary tuberculosis is guided by serial sputum smears. This can result in isolation for days for patients with noncontagious tuberculosis. To determine whether a single sample negative for Mycobacterium tuberculosis complex at polymerase chain...... reaction (PCR) can guide isolation. Methods. We retrospectively evaluated sputum samples analyzed for M. tuberculosis complex at the International Reference Laboratory of Mycobacteriology, Copenhagen, Denmark in 2002–2011. We selected culture-confirmed tuberculosis cases with ≥3 samples within 14 days...... before or after the initial culture-positive sample. We repeated the process for those with ≥2 samples within 28 days. The primary outcome was PCR-negative, smear-positive patients. Results. We included 53 533 sputum samples from 20 928 individuals; 1636 had culture-confirmed tuberculosis. Of these, 856...

Analysis of partial and total inelasticities obtained from inclusive reactions

International Nuclear Information System (INIS)

Bellandi, J.; Covolan, R.; Costa, C.G.; Montanha, J.; Mundim, L.M.

1994-01-01

An independent analysis of model for energetic dependence on inelasticity is presented, from experimental data of pp → c X (c = π +- , Κ +- , p +- ) type inclusive reactions. 6 refs., 2 figs., 1 tab

Development of the Performance Confirmation Program at Yucca Mountain, Nevada

International Nuclear Information System (INIS)

G.D. LeCain; D. Barr; D. Weaver; R. Snell; S.W. Goodin; F.D. Hansen

2006-01-01

The Yucca Mountain Performance Confirmation program consists of tests, monitoring activities, experiments, and analyses to evaluate the adequacy of assumptions, data, and analyses that form the basis of the conceptual and numerical models of flow and transport associated with a proposed radioactive waste repository at Yucca Mountain, Nevada. The Performance Confirmation program uses an eight-stage risk-informed, performance-based approach. Selection of the Performance Confirmation activities (a parameter and a test method) for inclusion in the Performance Confirmation program was done using a risk-informed performance-based decision analysis. The result of this analysis and review was a Performance Confirmation base portfolio that consists of 20 activities. The 20 Performance Confirmation activities include geologic, hydrologic, and construction/engineering testing. Several of the activities were initiated during site characterization and are ongoing. Others activities will commence during construction and/or post emplacement and will continue until repository closure

Derivation of the reduced reaction mechanisms of ozone depletion events in the Arctic spring by using concentration sensitivity analysis and principal component analysis

Directory of Open Access Journals (Sweden)

L. Cao

2016-12-01

Full Text Available The ozone depletion events (ODEs in the springtime Arctic have been investigated since the 1980s. It is found that the depletion of ozone is highly associated with an auto-catalytic reaction cycle, which involves mostly the bromine-containing compounds. Moreover, bromide stored in various substrates in the Arctic such as the underlying surface covered by ice and snow can be also activated by the absorbed HOBr. Subsequently, this leads to an explosive increase of the bromine amount in the troposphere, which is called the “bromine explosion mechanism”. In the present study, a reaction scheme representing the chemistry of ozone depletion and halogen release is processed with two different mechanism reduction approaches, namely, the concentration sensitivity analysis and the principal component analysis. In the concentration sensitivity analysis, the interdependence of the mixing ratios of ozone and principal bromine species on the rate of each reaction in the ODE mechanism is identified. Furthermore, the most influential reactions in different time periods of ODEs are also revealed. By removing 11 reactions with the maximum absolute values of sensitivities lower than 10 %, a reduced reaction mechanism of ODEs is derived. The onsets of each time period of ODEs in simulations using the original reaction mechanism and the reduced reaction mechanism are identical while the maximum deviation of the mixing ratio of principal bromine species between different mechanisms is found to be less than 1 %. By performing the principal component analysis on an array of the sensitivity matrices, the dependence of a particular species concentration on a combination of the reaction rates in the mechanism is revealed. Redundant reactions are indicated by principal components corresponding to small eigenvalues and insignificant elements in principal components with large eigenvalues. Through this investigation, aside from the 11 reactions identified as

Thermogravimetric analysis of the beryllium/steam reaction

Energy Technology Data Exchange (ETDEWEB)

Druyts, Frank E-mail: fdruyts@sckcen.be; Iseghem, Pierre van

2000-11-01

In view of the safety assessment of new fusion reactor designs, kinetic data are needed on the beryllium/steam reaction. Therefore, thermogravimetric analysis was used to determine the reactivity of beryllium in steam as a function of temperature, irradiation history and porosity of the samples. To this purpose, reference unirradiated S-200 VHP beryllium samples were compared with specimens irradiated in the BR2 reactor up to fast neutron fluences (E>1 MeV) of respectively 1.6x10{sup 21} n cm{sup -2} (resulting in a helium content of 300 appm He and a theoretical density of 99.9%) and 4x10{sup 22} n cm{sup -2} (21000 appm He, 97.2% theoretical density). Kinetics were parabolic for all tested beryllium types at 600 deg. C. At 700 deg. C, kinetics were parabolic for the unirradiated and irradiated 99.9% dense beryllium, and accelerating/linear for the irradiated 97.2% material. At 800 deg. C, all samples showed accelerating/linear behaviour. There was no influence of porosity on the reaction rate of beryllium in steam within the limited investigated density range, except at 700 deg. C, where the measured reaction rate for the irradiated 97.2% dense samples is an order of magnitude higher than for the irradiated 99.9% dense specimens.

Use of deuteron-induced nuclear reactions for quantitative surface analysis

International Nuclear Information System (INIS)

Simpson, J.C.B.; Earwaker, L.G.

1986-01-01

A summary of the basic features of nuclear reaction analysis is given; particular emphasis is placed on quantitative light element determination using (d,p) and (d,α) reactions. The experimental apparatus is also described, with reference to the 3MV Dynamitron accelerator at the University of Birmingham Radiation Centre. Finally, a set of standard (d, p) spectra for the elements Z=3 to Z=17, using 2 MeV incident deuterons, is included together with examples of the more useful of the (d,α) spectra. (orig.)

Phi-value analysis of a linear, sequential reaction mechanism: theory and application to ion channel gating.

Science.gov (United States)

Zhou, Yu; Pearson, John E; Auerbach, Anthony

2005-12-01

We derive the analytical form of a rate-equilibrium free-energy relationship (with slope Phi) for a bounded, linear chain of coupled reactions having arbitrary connecting rate constants. The results confirm previous simulation studies showing that Phi-values reflect the position of the perturbed reaction within the chain, with reactions occurring earlier in the sequence producing higher Phi-values than those occurring later in the sequence. The derivation includes an expression for the transmission coefficients of the overall reaction based on the rate constants of an arbitrary, discrete, finite Markov chain. The results indicate that experimental Phi-values can be used to calculate the relative heights of the energy barriers between intermediate states of the chain but provide no information about the energies of the wells along the reaction path. Application of the equations to the case of diliganded acetylcholine receptor channel gating suggests that the transition-state ensemble for this reaction is nearly flat. Although this mechanism accounts for many of the basic features of diliganded and unliganded acetylcholine receptor channel gating, the experimental rate-equilibrium free-energy relationships appear to be more linear than those predicted by the theory.

Study of the (d,α) reactions on the nuclei 10B, 11B, 12C, and 13C and the reaction 13C(p,α)10B and their microscopic and semicroscopic analysis

International Nuclear Information System (INIS)

Abd el-Kariem, S.E.S.

1984-01-01

In the framework of a systematic analysis of many-particle transfer reactions on light nuclei in the present thesis the two-particle transfer reactions of the type (d,α) on the nucleus 10 B at Esub(d) = 16 MeV and on the nuclei 11 B, 12 C and 13 C at Esub(d) = 24 MeV as well as the three-particle transfer reaction 13 C(p,α) 10 B at eight incident energies between 16 and 45 MeV have been studied. In the case of the residual nuclei 10 B and 11 B transitions up to an excitation energy Esub(x) approx.= 7.5 respectively approx.= 9,0 MeV, in the case of the residual nuclei 8 Be and 9 Be transitions up to Esub(x) approx.= 17 respectively 2.5 MeV were evaluated. Under the assumption that the studied reactions behave as direct one-stage transfer processes the measurement results were analyzed in the framework of the DWBA theory in zero-range approximation. The parameters for the optical potentials used in the DWBA calculations were taken from literature and partly modified by fitting to the angular distributions of the reactions studied here. Microscopic and semimicroscopic calculations were performed. In the semimicroscopic calculations the spectroscopic amplitudes calculated microscopically or in SU(3) approximation were used together with a cluster form factor, in the other case with a microscopically calculated form factor. For the residual nucleus for some higher excited states results on spin, parity, and isospin could be partly obtained, partly confirmed. (orig./HSI) [de

NUCLEAR MAGNETIC RESONANCE THE GELLED PRODUCT OF CANNIZZARO REACTION

Directory of Open Access Journals (Sweden)

Lilia Fernández-Sánchez

2015-03-01

Full Text Available The paper presents the nuclear magnetic resonance (NMR of proton 1H, carbon 13C and two dimensional spectrums, product of a green organic synthesis of redox on the Cannizzaro reaction. The product was reported as a tribochemical gel (heterogeneous mixture and confirmed by Infrared Spectroscopy IR, X-ray and scanning electron microscope (SEM. The results in this paper confirm its structure through various techniques of NMR and evaluate the content of sodium benzoate and benzyl alcohol in the spectroscopy sample, examining the values of the integrals on 1H NMR signals. The result of analysis indicates that benzyl alcohol (dispersed phase is in 33.44% mol in comparison with sodium benzoate content (continuous phase. These results confirm that the gel structure over time loses the dispersed phase of the benzyl alcohol producing a xerogel.

Stochastic analysis of complex reaction networks using binomial moment equations.

Science.gov (United States)

Barzel, Baruch; Biham, Ofer

2012-09-01

The stochastic analysis of complex reaction networks is a difficult problem because the number of microscopic states in such systems increases exponentially with the number of reactive species. Direct integration of the master equation is thus infeasible and is most often replaced by Monte Carlo simulations. While Monte Carlo simulations are a highly effective tool, equation-based formulations are more amenable to analytical treatment and may provide deeper insight into the dynamics of the network. Here, we present a highly efficient equation-based method for the analysis of stochastic reaction networks. The method is based on the recently introduced binomial moment equations [Barzel and Biham, Phys. Rev. Lett. 106, 150602 (2011)]. The binomial moments are linear combinations of the ordinary moments of the probability distribution function of the population sizes of the interacting species. They capture the essential combinatorics of the reaction processes reflecting their stoichiometric structure. This leads to a simple and transparent form of the equations, and allows a highly efficient and surprisingly simple truncation scheme. Unlike ordinary moment equations, in which the inclusion of high order moments is prohibitively complicated, the binomial moment equations can be easily constructed up to any desired order. The result is a set of equations that enables the stochastic analysis of complex reaction networks under a broad range of conditions. The number of equations is dramatically reduced from the exponential proliferation of the master equation to a polynomial (and often quadratic) dependence on the number of reactive species in the binomial moment equations. The aim of this paper is twofold: to present a complete derivation of the binomial moment equations; to demonstrate the applicability of the moment equations for a representative set of example networks, in which stochastic effects play an important role.

Ion beam analysis - development and application of nuclear reaction analysis methods, in particular at a nuclear microprobe

International Nuclear Information System (INIS)

Sjoeland, K.A.

1996-11-01

This thesis treats the development of Ion Beam Analysis methods, principally for the analysis of light elements at a nuclear microprobe. The light elements in this context are defined as having an atomic number less than approx. 13. The work reported is to a large extent based on multiparameter methods. Several signals are recorded simultaneously, and the data can be effectively analyzed to reveal structures that can not be observed through one-parameter collection. The different techniques are combined in a new set-up at the Lund Nuclear Microprobe. The various detectors for reaction products are arranged in such a way that they can be used for the simultaneous analysis of hydrogen, lithium, boron and fluorine together with traditional PIXE analysis and Scanning Transmission Ion Microscopy as well as photon-tagged Nuclear Reaction Analysis. 48 refs

Automatized Assessment of Protective Group Reactivity: A Step Toward Big Reaction Data Analysis.

Science.gov (United States)

Lin, Arkadii I; Madzhidov, Timur I; Klimchuk, Olga; Nugmanov, Ramil I; Antipin, Igor S; Varnek, Alexandre

2016-11-28

We report a new method to assess protective groups (PGs) reactivity as a function of reaction conditions (catalyst, solvent) using raw reaction data. It is based on an intuitive similarity principle for chemical reactions: similar reactions proceed under similar conditions. Technically, reaction similarity can be assessed using the Condensed Graph of Reaction (CGR) approach representing an ensemble of reactants and products as a single molecular graph, i.e., as a pseudomolecule for which molecular descriptors or fingerprints can be calculated. CGR-based in-house tools were used to process data for 142,111 catalytic hydrogenation reactions extracted from the Reaxys database. Our results reveal some contradictions with famous Greene's Reactivity Charts based on manual expert analysis. Models developed in this study show high accuracy (ca. 90%) for predicting optimal experimental conditions of protective group deprotection.

Reactivity of Single-Walled Carbon Nanotubes in the Diels-Alder Cycloaddition Reaction: Distortion-Interaction Analysis along the Reaction Pathway.

Science.gov (United States)

Li, Yingzi; Osuna, Sílvia; Garcia-Borràs, Marc; Qi, Xiaotian; Liu, Song; Houk, Kendall N; Lan, Yu

2016-08-26

Diels-Alder cycloaddition is one of the most powerful tools for the functionalization of single-walled carbon nanotubes (SWCNTs). Density functional theory at the B3-LYP level of theory has been used to investigate the reactivity of different-diameter SWCNTs (4-9,5) in Diels-Alder reactions with 1,3-butadiene; the reactivity was found to decrease with increasing SWCNT diameter. Distortion/interaction analysis along the whole reaction pathway was found to be a better way to explore the reactivity of this type of reaction. The difference in interaction energy along the reaction pathway is larger than that of the corresponding distortion energy. However, the distortion energy plots for these reactions show the same trend. Therefore, the formation of the transition state can be determined from the interaction energy. A lower interaction energy leads to an earlier transition state, which indicates a lower activation energy. The computational results also indicate that the original distortion of the SWCNTs leads to an increase in the reactivity of the SWCNTs. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A New Way to Confirm Planet Candidates

Science.gov (United States)

Kohler, Susanna

2016-05-01

What was the big deal behind the Kepler news conference yesterday? Its not just that the number of confirmed planets found by Kepler has more than doubled (though thats certainly exciting news!). Whats especially interesting is the way in which these new planets were confirmed.Number of planet discoveries by year since 1995, including previous non-Kepler discoveries (blue), previous Kepler discoveries (light blue) and the newly validated Kepler planets (orange). [NASA Ames/W. Stenzel; Princeton University/T. Morton]No Need for Follow-UpBefore Kepler, the way we confirmed planet candidates was with follow-up observations. The candidate could be validated either by directly imaging (which is rare) or obtaining a large number radial-velocity measurements of the wobble of the planets host star due to the planets orbit. But once Kepler started producing planet candidates, these approaches to validation became less feasible. A lot of Kepler candidates are small and orbit faint stars, making follow-up observations difficult or impossible.This problem is what inspired the development of whats known as probabilistic validation, an analysis technique that involves assessing the likelihood that the candidates signal is caused by various false-positive scenarios. Using this technique allows astronomers to estimate the likelihood of a candidate signal being a true planet detection; if that likelihood is high enough, the planet candidate can be confirmed without the need for follow-up observations.A breakdown of the catalog of Kepler Objects of Interest. Just over half had previously been identified as false positives or confirmed as candidates. 1284 are newly validated, and another 455 have FPP of1090%. [Morton et al. 2016]Probabilistic validation has been used in the past to confirm individual planet candidates in Kepler data, but now Timothy Morton (Princeton University) and collaborators have taken this to a new level: they developed the first code thats designed to do fully

Coupled-reaction-channel analysis of the (d,6Li) reaction on 24Mg and 26Mg to low-lying states

International Nuclear Information System (INIS)

Oelert, W.

1986-01-01

Experimental spectroscopic factors of the alpha-transfer reaction on nuclei of the sd-shell show rather strong inconsistencies and scatter much more strongly than explainable by the quoted errors. The poorer the quality of agreement between experimental and theoretical angular distribution shapes, the more inconsistent the comparison of spectroscopic factors either between different experiments or between theory and experiment. In view of the strong deformation of nuclei in the lower part of the sd-shell, higher-order reaction mechanisms are expected. A coupled-reaction-channel analysis for the transitions to the 0 + , 2 + , and 4 + states of the ground-state bands in 20 Ne and 22 Ne excited via the (d, 6 Li) reaction yields good agreement between experimental and theoretical angular distribution shapes as well as spectroscopic information. (orig.)

Analysis of the Sodium-Water Reaction Phenomena by Small Water/Steam Leaks

International Nuclear Information System (INIS)

Jeong, J-Y; Kim, T-J; Kim, J-M; Kim, B-H; Park, N-C

2006-01-01

One of the important problems to be solved in the design and construction of a sodium cooled fast reactor is to confirm the safety and reliability of the steam generator which transfers the heat from the sodium to the water. Sodium-water reaction events may occur when material faults such as a pinhole or cracks occur in the heat transfer tube wall. When such a leak occurs, evaporating water or superheated steam enters through a small leak into the sodium. The surface of this steam jet reacts with the surrounding sodium. Due to turbulence, sodium and particles of the reaction products are drawn at a high velocity into the jet. Impingement of these particles on an adjacent tube is followed by a combined process of a corrosion and erosion which results in a local weakening of the affected tube. If there is no reliable detection available in time, wastage will ultimately result in an additional leak in the adjacent tube. Therefore, it is very significant to predict these phenomena quantitatively from the view of designing a steam generator and its leak detection systems. The objective of this study is a basic investigating of the sodium-water reaction phenomena by small water/steam leaks

Sodium/water reaction detection confirmation and location with time domain beam former

International Nuclear Information System (INIS)

Cornu, C.

1997-01-01

The CEA studied the validity of a time beamforming method for the detection and location of Sodium/water reaction in steam generators of breeder reactors. In the context of the RCM, we apply this method on recorded data during a water injection in Sodium in ASB loop, artificially mixed with PFR background. Despite the severity of experiment conditions (the signal to noise ratio is between -6 and -24 dB). We show that the employed method completed with a low frequency pass band filter allows us to locate the injection with a precision of 30% of the diameter of the loop. Using the method in the course of time allows us to coarsely locate the start time and the duration of the leak. The good functioning of the method is however perturbed by uncertainty about the wave celebrity in the sodium about wave propagation in waves guides that are mounted with the sensors and in the structure of the loop. (author). 1 ref., 8 figs

An unexpected reaction pathway in the synthesis of the ABCE framework of strychnine-type alkaloids - A multidisciplinary study

Science.gov (United States)

Šoral, Michal; Markus, Jozef; Doháňošová, Jana; Šoralová, Stanislava; Dvoranová, Dana; Chyba, Andrej; Moncol, Ján; Berkeš, Dušan; Liptaj, Tibor

2017-01-01

Acid-catalyzed cyclization of spirocyclic 1‧-benzyl-2‧-(prop-2-en-1-yl)spiro[indole-3,3‧-pyrrolidine]-5‧-one (1) was performed. The pentacyclic product of Povarov-like imino-Diels-Alder reaction was isolated in high yield instead of expected tetracyclic aza-Prins intermediate. The unusual exotic alkaloid-type structure of the resulting molecule 2 was unambiguously confirmed by a detailed NMR analysis using a set of 2D NMR spectra including an INADEQUATE experiment. The relative configuration of 2 was predicted from the synthesis mechanism and DFT geometry calculations and independently confirmed using NOESY and residual dipolar coupling (RDC) assisted NMR analysis in stretched crosslinked polystyrene gels. The reversibility of the cycloaddition in aprotic solvents was observed. A new reaction pathway yielding a rare 6-5-5-5 tetracyclic spiroindoline 3 was suggested. The relative configuration within the tetracyclic framework was ultimately proved using Single-crystal X-ray diffraction analysis of compound 4.

Regression analysis of a chemical reaction fouling model

International Nuclear Information System (INIS)

Vasak, F.; Epstein, N.

1996-01-01

A previously reported mathematical model for the initial chemical reaction fouling of a heated tube is critically examined in the light of the experimental data for which it was developed. A regression analysis of the model with respect to that data shows that the reference point upon which the two adjustable parameters of the model were originally based was well chosen, albeit fortuitously. (author). 3 refs., 2 tabs., 2 figs

Parametric sensitivity analysis for biochemical reaction networks based on pathwise information theory.

Science.gov (United States)

Pantazis, Yannis; Katsoulakis, Markos A; Vlachos, Dionisios G

2013-10-22

Stochastic modeling and simulation provide powerful predictive methods for the intrinsic understanding of fundamental mechanisms in complex biochemical networks. Typically, such mathematical models involve networks of coupled jump stochastic processes with a large number of parameters that need to be suitably calibrated against experimental data. In this direction, the parameter sensitivity analysis of reaction networks is an essential mathematical and computational tool, yielding information regarding the robustness and the identifiability of model parameters. However, existing sensitivity analysis approaches such as variants of the finite difference method can have an overwhelming computational cost in models with a high-dimensional parameter space. We develop a sensitivity analysis methodology suitable for complex stochastic reaction networks with a large number of parameters. The proposed approach is based on Information Theory methods and relies on the quantification of information loss due to parameter perturbations between time-series distributions. For this reason, we need to work on path-space, i.e., the set consisting of all stochastic trajectories, hence the proposed approach is referred to as "pathwise". The pathwise sensitivity analysis method is realized by employing the rigorously-derived Relative Entropy Rate, which is directly computable from the propensity functions. A key aspect of the method is that an associated pathwise Fisher Information Matrix (FIM) is defined, which in turn constitutes a gradient-free approach to quantifying parameter sensitivities. The structure of the FIM turns out to be block-diagonal, revealing hidden parameter dependencies and sensitivities in reaction networks. As a gradient-free method, the proposed sensitivity analysis provides a significant advantage when dealing with complex stochastic systems with a large number of parameters. In addition, the knowledge of the structure of the FIM can allow to efficiently address

Statistical analysis of activation and reaction energies with quasi-variational coupled-cluster theory

Science.gov (United States)

Black, Joshua A.; Knowles, Peter J.

2018-06-01

The performance of quasi-variational coupled-cluster (QV) theory applied to the calculation of activation and reaction energies has been investigated. A statistical analysis of results obtained for six different sets of reactions has been carried out, and the results have been compared to those from standard single-reference methods. In general, the QV methods lead to increased activation energies and larger absolute reaction energies compared to those obtained with traditional coupled-cluster theory.

Surface reactivity and layer analysis of chemisorbed reaction films in ...

Indian Academy of Sciences (India)

Administrator

Surface reactivity and layer analysis of chemisorbed reaction films in ... in the nitrogen environment. Keywords. Surface reactivity ... sium (Na–K) compounds in the coating or core of the ..... Barkshire I R, Pruton M and Smith G C 1995 Appl. Sur.

The value of routine polymerase chain reaction analysis of intraocular fluid specimens in the diagnosis of infectious posterior uveitis.

Science.gov (United States)

Scheepers, Marius A; Lecuona, Karin A; Rogers, Graeme; Bunce, Catey; Corcoran, Craig; Michaelides, Michel

2013-01-01

To assess the value of routine polymerase chain reaction (PCR) analysis on intraocular fluid from patients presenting with a first episode of suspected active infectious posterior uveitis in a population with a high prevalence of human immunodeficiency virus infection. Retrospective, interventional case series. Participants. 159 consecutive patients presenting at a tertiary care hospital over a five-year period. PCR analysis was performed for cytomegalovirus, varicella zoster virus, herpes simplex virus types 1 and 2, Toxoplasma gondii, and Mycobacterium tuberculosis. PCR analysis confirmed the initial clinical diagnosis in 55 patients (35%) and altered the initial clinical diagnosis in 36 patients (23%). The clinical diagnosis prior to PCR testing was nonspecific (uncertain) in 51 patients (32%), with PCR providing a definitive final diagnosis in 20 of these patients (39%); necrotizing herpetic retinopathy and ocular toxoplasmosis were particularly difficult to diagnose correctly without the use of PCR analysis. The clinical phenotype alone was unreliable in diagnosing the underlying infectious cause in a quarter of patients in this study. Since the outcome of incorrectly treated infective uveitis can be blinding, PCR analysis of ocular fluids is recommended early in the disease even in resource poor settings.

Determination and theoretical analysis of the differential cross sections of the 2H(d,p) reaction at energies and detection angles suitable for NRA (Nuclear Reaction Analysis)

International Nuclear Information System (INIS)

Paneta, V.; Axiotis, M.; Lagoyannis, A.; Gastis, P.; Kokkoris, M.; Vlastou, R.; Kontos, A.; Mayer, M.; Misaelides, P.; Perdikakis, G.

2014-01-01

The accurate determination of deuteron depth profile presents a strong analytical challenge for all the principal IBA (Ion Beam Analysis) techniques. As far as NRA (Nuclear Reaction Analysis) is concerned, the 2 H(d,p) reaction, seems to be a promising candidate, especially in the case of complex matrices, or for the study of deep-implanted deuteron layers. In the present work differential cross-section values for the 2 H(d,p) reaction have been determined at 140, 160 and 170 degrees, for E d (lab) = 900-1600 keV, with an energy step of 50 keV, using a well-characterized, thin C:D target deposited on a polished Si wafer. The detection system consisted of 3 silicon surface barrier (SSB) detectors (thickness of 1000 μm) placed at a distance of about 11-13 cm from the target, at the appropriate angles. The experimental results were analyzed using the R-matrix calculations code AZURE. The results, in graphical and tabular form, will soon be available to the scientific community through IBANDL

iADRs: towards online adverse drug reaction analysis.

Science.gov (United States)

Lin, Wen-Yang; Li, He-Yi; Du, Jhih-Wei; Feng, Wen-Yu; Lo, Chiao-Feng; Soo, Von-Wun

2012-12-01

Adverse Drug Reaction (ADR) is one of the most important issues in the assessment of drug safety. In fact, many adverse drug reactions are not discovered during limited pre-marketing clinical trials; instead, they are only observed after long term post-marketing surveillance of drug usage. In light of this, the detection of adverse drug reactions, as early as possible, is an important topic of research for the pharmaceutical industry. Recently, large numbers of adverse events and the development of data mining technology have motivated the development of statistical and data mining methods for the detection of ADRs. These stand-alone methods, with no integration into knowledge discovery systems, are tedious and inconvenient for users and the processes for exploration are time-consuming. This paper proposes an interactive system platform for the detection of ADRs. By integrating an ADR data warehouse and innovative data mining techniques, the proposed system not only supports OLAP style multidimensional analysis of ADRs, but also allows the interactive discovery of associations between drugs and symptoms, called a drug-ADR association rule, which can be further developed using other factors of interest to the user, such as demographic information. The experiments indicate that interesting and valuable drug-ADR association rules can be efficiently mined.

Efficient Isomerization of Glucose to Fructose over Zeolites in Consecutive Reactions in Alcohol and Aqueous Media

DEFF Research Database (Denmark)

Shunmugavel, Saravanamurugan; Paniagua, Marta; Melero, Juan A

2013-01-01

glucose isomerization to fructose and subsequent reaction with methanol to form methyl fructoside (step 1), followed by hydrolysis to re-form fructose after water addition (step 2). NMR analysis with (13)C-labeled sugars confirmed this reaction pathway. Conversion of glucose for 1 h at 120 °C with H......-USY (Si/Al = 6) gave a remarkable 55% yield of fructose after the second reaction step. A main advantage of applying alcohol media and a catalyst that combines Brønsted and Lewis acid sites is that glucose is isomerized to fructose at low temperatures, while direct conversion to industrially important...

(MIRC) reaction w

Indian Academy of Sciences (India)

Sudesh Kumari

eco-friendly solvents, high yields and easy work-up procedure. Keywords. Ethylene glycol; 4-hydroxycoumarin; ... ability and also compatibility with most organic and inorganic compounds. Because of these properties it is ..... phenyl amino)-2H-chromen-2-one (8a) was isolated from the reaction mixture to confirm the ...

[Incidence rate of adverse reaction/event by Qingkailing injection: a Meta-analysis of single rate].

Science.gov (United States)

Ai, Chun-ling; Xie, Yan-ming; Li, Ming-quan; Wang, Lian-xin; Liao, Xing

2015-12-01

To systematically review the incidence rate of adverse drug reaction/event by Qingkailing injection. Such databases as the PubMed, EMbase, the Cochrane library, CNKI, VIP WanFang data and CBM were searched by computer from foundation to July 30, 2015. Two reviewers independently screened literature according to the inclusion and exclusion criteria, extracted data and cross check data. Then, Meta-analysis was performed by using the R 3.2.0 software, subgroup sensitivity analysis was performed based on age, mode of medicine, observation time and research quality. Sixty-three studies involving 9,793 patients with Qingkailing injection were included, 367 cases of adverse reactions/events were reported in total. The incidence rate of adverse reaction in skin and mucosa group was 2% [95% CI (0.02; 0.03)]; the digestive system adverse reaction was 6% [95% CI(0.05; 0.07); the injection site adverse reaction was 4% [95% CI (0.02; 0.07)]. In the digestive system as the main types of adverse reactions/events, incidence of children and adults were 4.6% [0.021 1; 0.097 7] and 6.9% [0.053 5; 0.089 8], respectively. Adverse reactions to skin and mucous membrane damage as the main performance/event type, the observation time > 7 days and ≤ 7 days incidence of 3% [0.012 9; 0.068 3] and 1.9% [0.007 8; 0.046 1], respectively. Subgroup analysis showed that different types of adverse reactions, combination in the incidence of adverse reactions/events were higher than that of single drug, the difference was statistically significant (P reactions occur, and clinical rational drug use, such as combination, age and other fators, and the influence factors vary in different populations. Therefore, clinical doctors for children and the elderly use special care was required for a clear and open spirit injection, the implementation of individualized medication.

Confirmation of the definitive structure of Fleishmann's lactone by NMR

International Nuclear Information System (INIS)

Figueroa Villar, Jose Daniel

1993-01-01

The reaction between 4-hydroxy-6-methyl-pyrone and ethyl-acetic-acetate produces a compound known since the beginning of the century, named Fleishman lactone in honor to its discover. The structure of this compound has been the aim of several researches due to its similarity with several poly-pyrones which are important in synthesis of important products. This work presents the accurate determination of the structure of the Fleishman lactone. The methodology is presented as well as confirmation tests

Multilayer Network Analysis of Nuclear Reactions

Science.gov (United States)

Zhu, Liang; Ma, Yu-Gang; Chen, Qu; Han, Ding-Ding

2016-08-01

The nuclear reaction network is usually studied via precise calculation of differential equation sets, and much research interest has been focused on the characteristics of nuclides, such as half-life and size limit. In this paper, however, we adopt the methods from both multilayer and reaction networks, and obtain a distinctive view by mapping all the nuclear reactions in JINA REACLIB database into a directed network with 4 layers: neutron, proton, 4He and the remainder. The layer names correspond to reaction types decided by the currency particles consumed. This combined approach reveals that, in the remainder layer, the β-stability has high correlation with node degree difference and overlapping coefficient. Moreover, when reaction rates are considered as node strength, we find that, at lower temperatures, nuclide half-life scales reciprocally with its out-strength. The connection between physical properties and topological characteristics may help to explore the boundary of the nuclide chart.

ACT-XN: Revised version of an activation calculation code for fusion reactor analysis. Supplement of the function for the sequential reaction activation by charged particles

International Nuclear Information System (INIS)

Yamauchi, Michinori; Sato, Satoshi; Nishitani, Takeo; Konno, Chikara; Hori, Jun-ichi; Kawasaki, Hiromitsu

2007-09-01

The ACT-XN is a revised version of the ACT4 code, which was developed in the Japan Atomic Energy Research Institute (JAERI) to calculate the transmutation, induced activity, decay heat, delayed gamma-ray source etc. for fusion devices. The ACT4 code cannot deal with the sequential reactions of charged particles generated by primary neutron reactions. In the design of present experimental reactors, the activation due to sequential reactions may not be of great concern as it is usually buried under the activity by primary neutron reactions. However, low activation material is one of the important factors for constructing high power fusion reactors in future, and unexpected activation may be produced through sequential reactions. Therefore, in the present work, the ACT4 code was newly supplemented with the calculation functions for the sequential reactions and renamed the ACT-XN. The ACT-XN code is equipped with functions to calculate effective cross sections for sequential reactions and input them in transmutation matrix. The FISPACT data were adopted for (x,n) reaction cross sections, charged particles emission spectra and stopping powers. The nuclear reaction chain data library were revised to cope with the (x,n) reactions. The charged particles are specified as p, d, t, 3 He(h) and α. The code was applied to the analysis of FNS experiment for LiF and Demo-reactor design with FLiBe, and confirmed that it reproduce the experimental values within 15-30% discrepancies. In addition, a notice was presented that the dose rate due to sequential reaction cannot always be neglected after a certain period cooling for some of the low activation material. (author)

The impact of meningococcal polymerase chain reaction testing on laboratory confirmation of invasive meningococcal disease.

LENUS (Irish Health Repository)

Drew, Richard J

2012-03-01

Laboratory methods of diagnosis were examined for 266 children with invasive meningococcal disease. Seventy-five (36%) of 207 cases with bloodstream infection had both positive blood culture and blood meningococcal polymerase chain reaction (PCR), 130 (63%) negative blood culture and positive blood PCR, and 2 (1%) had positive blood culture and negative blood PCR. Sixty-three percent of cases were diagnosed by PCR alone.

A comparison of approximation techniques for variance-based sensitivity analysis of biochemical reaction systems

Directory of Open Access Journals (Sweden)

Goutsias John

2010-05-01

Full Text Available Abstract Background Sensitivity analysis is an indispensable tool for the analysis of complex systems. In a recent paper, we have introduced a thermodynamically consistent variance-based sensitivity analysis approach for studying the robustness and fragility properties of biochemical reaction systems under uncertainty in the standard chemical potentials of the activated complexes of the reactions and the standard chemical potentials of the molecular species. In that approach, key sensitivity indices were estimated by Monte Carlo sampling, which is computationally very demanding and impractical for large biochemical reaction systems. Computationally efficient algorithms are needed to make variance-based sensitivity analysis applicable to realistic cellular networks, modeled by biochemical reaction systems that consist of a large number of reactions and molecular species. Results We present four techniques, derivative approximation (DA, polynomial approximation (PA, Gauss-Hermite integration (GHI, and orthonormal Hermite approximation (OHA, for analytically approximating the variance-based sensitivity indices associated with a biochemical reaction system. By using a well-known model of the mitogen-activated protein kinase signaling cascade as a case study, we numerically compare the approximation quality of these techniques against traditional Monte Carlo sampling. Our results indicate that, although DA is computationally the most attractive technique, special care should be exercised when using it for sensitivity analysis, since it may only be accurate at low levels of uncertainty. On the other hand, PA, GHI, and OHA are computationally more demanding than DA but can work well at high levels of uncertainty. GHI results in a slightly better accuracy than PA, but it is more difficult to implement. OHA produces the most accurate approximation results and can be implemented in a straightforward manner. It turns out that the computational cost of the

Reaction kinetic analysis of reactor surveillance data

Energy Technology Data Exchange (ETDEWEB)

Yoshiie, T., E-mail: yoshiie@rri.kyoto-u.ac.jp [Research Reactor Institute, Kyoto University, Kumatori-cho, Sennan-gun, Osaka-fu 590-0494 (Japan); Kinomura, A. [Research Reactor Institute, Kyoto University, Kumatori-cho, Sennan-gun, Osaka-fu 590-0494 (Japan); Nagai, Y. [The Oarai Center, Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313 (Japan)

2017-02-15

In the reactor pressure vessel surveillance data of a European-type pressurized water reactor (low-Cu steel), it was found that the concentration of matrix defects was very high, and a large number of precipitates existed. In this study, defect structure evolution obtained from surveillance data was simulated by reaction kinetic analysis using 15 rate equations. The saturation of precipitation and the growth of loops were simulated, but it was not possible to explain the increase in DBTT on the basis of the defect structures. The sub-grain boundary segregation of solutes was discussed for the origin of the DBTT increase.

Status of CONRAD, a nuclear reaction analysis tool

International Nuclear Information System (INIS)

Saint Jean, C. de; Habert, B.; Litaize, O.; Noguere, G.; Suteau, C.

2008-01-01

The development of a software tool (CONRAD) was initiated at CEA/Cadarache to give answers to various problems arising in the data analysis of nuclear reactions. This tool is then characterized by the handling of uncertainties from experimental values to covariance matrices for multi-group cross sections. An object oriented design was chosen allowing an easy interface with graphical tool for input/output data and being a natural framework for innovative nuclear models (Fission). The major achieved developments are a data model for describing channels, nuclear reactions, nuclear models and processes with interface to classical data formats, theoretical calculations for the resolved resonance range (Reich-Moore) and unresolved resonance range (Hauser-Feshbach, Gilbert-Cameron,...) with nuclear model parameters adjustment on experimental data sets and a Monte Carlo method based on conditional probabilities developed to calculate properly covariance matrices. The on-going developments deal with the experimental data description (covariance matrices) and the graphical user interface. (authors)

Numerical Analysis Of Hooke Jeeves-Runge Kutta To Determine Reaction Rate Equation In Pyrrole Polymerization

International Nuclear Information System (INIS)

Gunawan, Indra; Sulistyo, Harry; Rochmad

2001-01-01

The numerical analysis of Hooke Jeeves Methods combined with Runge Kutta Methods is used to determine the exact model of reaction rate equation of pyrrole polymerization. Chemical polymerization of pyrrole was conducted with FeCI 3 / pyrrole solution at concentration ratio of 1.62 mole / mole and 2.18 mole / mole with varrying temperature of 28, 40, 50, and 60 o C. FeCl 3 acts as an oxidation agent to form pyrrole cation that will polymerize. The numerical analysis was done to examine the exact model of reaction rate equation which is derived from reaction equation of initiation, propagation, and termination. From its numerical analysis, it is found that the pyrrole polymerization follows third order of pyrrole cation concentration

Design of the US-CRBRP sodium/water reaction pressure relief system

International Nuclear Information System (INIS)

Kruger, G.B.; Murdock, T.B.; Rodwell, E.; Sane, J.O.

1976-01-01

Protection against intermediate sodium system overpressure from the sodium/water reaction associated with large leaks within the CRBRP Steam Generators is provided by the sodium/water reaction pressure relief system (SWRPRS). This system consists of rupture disks connected to the intermediate sodium piping adjacent to the inlet to the superheater and outlet from the evaporator modules. The rupture discs relieve into piping that leads to reaction produce separator tanks, which in turn are vented to a centrifugal separator and flare stack arranged to burn hydrogen gas exhausting into the atmosphere. Analyses have been conducted using the TRANSWRAP Computer Code to predict the system pressures and flow rates during the large leak event. Experimental tests to be conducted in the large leak test rig (LLTR) will be used to confirm the analysis techniques used in the design

Waste analysis plan for confirmation or completion of Tank Farms backlog waste designation

International Nuclear Information System (INIS)

1993-08-01

This waste analysis plan satisfies the requirements of Item 3 of Ecology Order 93NM-201 as amended per the Settlement Agreement. Item 3 states: ''Within forty (40) calendar days of receipt of this Order, the US Department of Energy Richland Operations (DOE-RL) and Westinghouse Hanford Company (WHC) shall provide Ecology with a plan for review and approval detailing the established criteria and procedures for waste inspection, segregation, sampling, designation, and repackaging of all containers reported in item number-sign 1. The report shall include sampling plan criteria for different contaminated media, i.e., soils, compactable waste, high-efficiency particular air (HEPA) filters, etc., and a schedule for completing the work within the time allowed under this Order.'' Item 3 was amended per the Settlement Agreement as follows: ''In addition to the waste inspection plans for the ''unknowns'' previously provided and currently being supplemented, DOE-RL and WHC shall provide a draft waste analysis plan for the containers reported in Item 1 of the Order to Ecology by July 12, 1993. A final, DOE-RL approved waste analysis plan shall be submitted to Ecology by September 1, 1993, for Ecology's written approval by September 15, 1993.'' Containers covered by the Order, Settlement Agreement, and this waste analysis plan consist of all those reported under Item 1 of the Order, less any containers that have been identified in unusual occurrences reported by Tank Farms. This waste analysis plan describes the procedures that will be undertaken to confirm or to complete designation of the solid waste identified in the Order

CONFIRMATION OF HOT JUPITER KEPLER-41b VIA PHASE CURVE ANALYSIS

International Nuclear Information System (INIS)

Quintana, Elisa V.; Rowe, Jason F.; Caldwell, Douglas A.; Christiansen, Jessie L.; Jenkins, Jon M.; Morris, Robert L.; Smith, Jeffrey C.; Thompson, Susan E.; Barclay, Thomas; Howell, Steve B.; Borucki, William J.; Sanderfer, Dwight T.; Still, Martin; Ciardi, David R.; Demory, Brice-Olivier; Klaus, Todd C.; Fulton, Benjamin J.; Shporer, Avi

2013-01-01

We present high precision photometry of Kepler-41, a giant planet in a 1.86 day orbit around a G6V star that was recently confirmed through radial velocity measurements. We have developed a new method to confirm giant planets solely from the photometric light curve, and we apply this method herein to Kepler-41 to establish the validity of this technique. We generate a full phase photometric model by including the primary and secondary transits, ellipsoidal variations, Doppler beaming, and reflected/emitted light from the planet. Third light contamination scenarios that can mimic a planetary transit signal are simulated by injecting a full range of dilution values into the model, and we re-fit each diluted light curve model to the light curve. The resulting constraints on the maximum occultation depth and stellar density combined with stellar evolution models rules out stellar blends and provides a measurement of the planet's mass, size, and temperature. We expect about two dozen Kepler giant planets can be confirmed via this method.

Repository performance confirmation

International Nuclear Information System (INIS)

Hansen, Francis D.

2011-01-01

Repository performance confirmation links the technical bases of repository science and societal acceptance. This paper explores the myriad aspects of what has been labeled performance confirmation in U.S. programs, which involves monitoring as a collection of distinct activities combining technical and social significance in radioactive waste management. This paper is divided into four parts: (1) A distinction is drawn between performance confirmation monitoring and other testing and monitoring objectives; (2) A case study illustrates confirmation activities integrated within a long-term testing and monitoring strategy for Yucca Mountain; (3) A case study reviews compliance monitoring developed and implemented for the Waste Isolation Pilot Plant; and (4) An approach for developing, evaluating and implementing the next generation of performance confirmation monitoring is presented. International interest in repository monitoring is exhibited by the European Commission Seventh Framework Programme 'Monitoring Developments for Safe Repository Operation and Staged Closure' (MoDeRn) Project. The MoDeRn partners are considering the role of monitoring in a phased approach to the geological disposal of radioactive waste. As repository plans advance in different countries, the need to consider monitoring strategies within a controlled framework has become more apparent. The MoDeRn project pulls together technical and societal experts to assimilate a common understanding of a process that could be followed to develop a monitoring program. A fundamental consideration is the differentiation of confirmation monitoring from the many other testing and monitoring activities. Recently, the license application for Yucca Mountain provided a case study including a technical process for meeting regulatory requirements to confirm repository performance as well as considerations related to the preservation of retrievability. The performance confirmation plan developed as part of the

Partial wave analysis of the 18O(p,α0)15N reaction

International Nuclear Information System (INIS)

Wild, L.W.J.; Spicer, B.M.

1979-01-01

A partial wave analysis of the differential cross sections for the 18 O(p,α 0 ) 15 N reaction has been carried out applying the formalism of Blatt and Biedenharn (1952), made specific for this reaction. The differential cross sections, measured at 200 keV intervals from 6.6 to 10.4 MeV bombarding energy, were subjected to least-squares fitting to this specific analytic expression. Two resonances were given by the analysis, the 19 F states being at 14.71+-0.07 MeV (1/2 - ) and 14.80 + 0.07 MeV (1/2) +

Broadly reactive pan-paramyxovirus reverse transcription polymerase chain reaction and sequence analysis for the detection of Canine distemper virus in a case of canine meningoencephalitis of unknown etiology

Science.gov (United States)

Schatzberg, Scott J.; Li, Qiang; Porter, Brian F.; Barber, Renee M.; Claiborne, Mary Kate; Levine, Jonathan M.; Levine, Gwendolyn J.; Israel, Sarah K.; Young, Benjamin D.; Kiupel, Matti; Greene, Craig; Ruone, Susan; Anderson, Larry; Tong, Suxiang

2016-01-01

Despite the immunologic protection associated with routine vaccination protocols, Canine distemper virus (CDV) remains an important pathogen of dogs. Antemortem diagnosis of systemic CDV infection may be made by reverse transcription polymerase chain reaction (RT-PCR) and/or immunohistochemical testing for CDV antigen; central nervous system infection often requires postmortem confirmation via histopathology and immunohistochemistry. An 8-month-old intact male French Bulldog previously vaccinated for CDV presented with multifocal neurologic signs. Based on clinical and postmortem findings, the dog’s disease was categorized as a meningoencephalitis of unknown etiology. Broadly reactive, pan-paramyxovirus RT-PCR using consensus-degenerate hybrid oligonucleotide primers, combined with sequence analysis, identified CDV amplicons in the dog’s brain. Immunohistochemistry confirmed the presence of CDV antigens, and a specific CDV RT-PCR based on the phosphoprotein gene identified a wild-type versus vaccinal virus strain. This case illustrates the utility of broadly reactive PCR and sequence analysis for the identification of pathogens in diseases with unknown etiology. PMID:19901287

Thermal analysis experiment for elucidating sodium-water chemical reaction mechanism in steam generator of sodium-cooled fast reactor

International Nuclear Information System (INIS)

Kikuchi, Shin; Kurihara, Akikazu; Ohshima, Hiroyuki

2012-01-01

For the purpose of elucidating the mechanism of the sodium-water surface reaction in a steam generator of sodium-cooled fast reactors, kinetic study of the sodium (Na)-sodium hydroxide (NaOH) reaction has been carried out by using Differential Thermal Analysis (DTA) technique. The parameters, including melting points of Na and NaOH, phase transition temperature of NaOH, Na-NaOH reaction temperature, and decomposition temperature of sodium hydride (NaH) have been identified from DTA curves. Based on the measured reaction temperature, rate constant of sodium monoxide (Na 2 O) generation was obtained. Thermal analysis results indicated that Na 2 O generation at the secondary overall reaction should be considered during the sodium-water reaction. (author)

Dynamic screening in solar and stellar nuclear reactions

Energy Technology Data Exchange (ETDEWEB)

Daeppen, W. [Department of Physics and Astronomy, University of Southern California, Los Angeles, CA (United States); Mussack, K. [Los Alamos National Laboratory, XTD-2, Los Alamos, NM (United States)

2012-02-15

In the hot, dense plasma of solar and stellar interiors, Coulomb potentials are screened, resulting in increased nuclear reaction rates. Although Salpeter's approximation for static screening is widely accepted and used in stellar modeling, the question of screening in nuclear reactions was revisited in the 1990s. In particular the issue of dynamic effects was raised by Shaviv and Shaviv, who applied the techniques of molecular dynamics to the conditions in the Sun's core in order to numerically determine the effect of screening. By directly calculating the motion of ions and electrons due to Coulomb interactions, the simulations are used to compute the effect of screening without the mean-field assumption inherent in Salpeter's approximation. In the last few years, the USC group has first reproduced Shaviv and Shaviv's numerical analysis of the screening energy, showing an effect of dynamic screening. When the consequence for the reaction-rate was computed, a rather surprising resulted, which is contrary to that from static screening theory. Our calculations showed that dynamic screening does not significantly change the reaction rate from that of the bare Coulomb potential. If this can be independently confirmed, then the effects of dynamic screening are highly relevant and should be included in stellar nuclear reaction rates (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Dynamical structure analysis of crystalline-state reaction and elucidation of chemical reactivity in crystalline environment

International Nuclear Information System (INIS)

Ohashi, Yuji

2010-01-01

It was found that a chiral alkyl group bonded to the cobalt atom in a cobalt complex crystal was racemized with retention of the single crystal form on exposure to visible light. Such reactions, which are called crystalline-state reactions, have been found in a variety of cobalt complex crystals. The concept of reaction cavity was introduced to explain the reaction rate quantitatively and the chirality of the photo-product. The new diffractometers and detectors were made for rapid data collection. The reaction mechanism was also elucidated using neutron diffraction analysis. The unstable reaction intermediates were analyzed using cryo-trapping method. The excited-state structures were obtained at the equilibrium state between ground and excited states. (author)

Confirmation of the absolute configuration of (−)-aurantioclavine

KAUST Repository

Behenna, Douglas C.; Krishnan, Shyam; Stoltz, Brian M.

2011-01-01

We confirm our previous assignment of the absolute configuration of (-)-aurantioclavine as 7R by crystallographically characterizing an advanced 3-bromoindole intermediate reported in our previous synthesis. This analysis also provides additional

Synthesis, optimization and structural characterization of a chitosan-glucose derivative obtained by the Maillard reaction.

Science.gov (United States)

Gullón, Beatriz; Montenegro, María I; Ruiz-Matute, Ana I; Cardelle-Cobas, Alejandra; Corzo, Nieves; Pintado, Manuela E

2016-02-10

Chitosan (Chit) was submitted to the Maillard reaction (MR) by co-heating a solution with glucose (Glc). Different reaction conditions as temperature (40, 60 and 80 °C), Glc concentration (0.5%, 1%, and 2%, w/v), and reaction time (72, 52 and 24h) were evaluated. Assessment of the reaction extent was monitored by measuring changes in UV absorbance, browning and fluorescence. Under the best conditions, 2% (w/v) of Chit, 2% (w/v) of Glc at 60°C and 32 h of reaction time, a chitosan-glucose (Chit-Glc) derivative was purified and submitted to structural characterization to confirm its formation. Analysis of its molecular weight (MW) and the degree of substitution (DS) was carried out by HPLC-Size Exclusion Chromatography (SEC) and a colloid titration method, respectively. FT-IR and (1)H NMR were also used to analyze the functional groups and evaluate the introduction of Glc into the Chit molecule. According to our objectives, the results obtained in this work allowed to better understand the key parameters influencing the MR with Chit as well as to confirm the successful introduction of Glc into the Chit molecule obtaining a Chit-Glc derivative with a DS of 64.76 ± 4.40% and a MW of 210.37 kDa. Copyright © 2015 Elsevier Ltd. All rights reserved.

Reaction time for trimolecular reactions in compartment-based reaction-diffusion models

Science.gov (United States)

Li, Fei; Chen, Minghan; Erban, Radek; Cao, Yang

2018-05-01

Trimolecular reaction models are investigated in the compartment-based (lattice-based) framework for stochastic reaction-diffusion modeling. The formulae for the first collision time and the mean reaction time are derived for the case where three molecules are present in the solution under periodic boundary conditions. For the case of reflecting boundary conditions, similar formulae are obtained using a computer-assisted approach. The accuracy of these formulae is further verified through comparison with numerical results. The presented derivation is based on the first passage time analysis of Montroll [J. Math. Phys. 10, 753 (1969)]. Montroll's results for two-dimensional lattice-based random walks are adapted and applied to compartment-based models of trimolecular reactions, which are studied in one-dimensional or pseudo one-dimensional domains.

Hydrogen release from irradiated elastomers measured by Nuclear Reaction Analysis

Energy Technology Data Exchange (ETDEWEB)

Jagielski, J., E-mail: jacek.jagielski@itme.edu.pl [Institute for Electronic Materials Technology, Wolczynska 133, 01-926 Warszawa (Poland); National Centre for Nuclear Research, A. Soltana 7, 05-400 Swierk/Otwock (Poland); Ostaszewska, U. [Institute for Engineering of Polymer Materials & Dyes, Division of Elastomers & Rubber Technology, Harcerska 30, 05-820 Piastow (Poland); Bielinski, D.M. [Technical University of Lodz, Institute of Polymer & Dye Technology, Stefanowskiego 12/16, 90-924 Lodz (Poland); Grambole, D. [Institute of Ion Beam Physics and Materials Research, Helmholtz Zentrum Dresden Rossendorf, PO Box 51 01 19, D-01314 Dresden (Germany); Romaniec, M.; Jozwik, I.; Kozinski, R. [Institute for Electronic Materials Technology, Wolczynska 133, 01-926 Warszawa (Poland); Kosinska, A. [National Centre for Nuclear Research, A. Soltana 7, 05-400 Swierk/Otwock (Poland)

2016-03-15

Ion irradiation appears as an interesting method of modification of elastomers, especially friction and wear properties. Main structural effect caused by heavy ions is a massive loss of hydrogen from the surface layer leading to its smoothening and shrinking. The paper presents the results of hydrogen release from various elastomers upon irradiation with H{sup +}, He{sup +} and Ar{sup +} studied by using Nuclear Reaction Analysis (NRA) method. The analysis of the experimental data indicates that the hydrogen release is controlled by inelastic collisions between ions and target electrons. The last part of the study was focused on preliminary analysis of mechanical properties of irradiated rubbers.

Oral lichenoid reaction to tobacco | Panta | Pan African Medical ...

African Journals Online (AJOL)

A differential diagnosis of lichen planus, oral lichenoid reaction and discoid lupus erythematosis were considered. On microscopic examination, there was focal perivascular infiltrate and plasma cells in the connective tissue. After correlating clinically, a diagnosis of "lichenoid reaction" was confirmed. Oral lichenoid ...

Metabolic control analysis of biochemical pathways based on a thermokinetic description of reaction rates

DEFF Research Database (Denmark)

Nielsen, Jens Bredal

1997-01-01

Metabolic control analysis is a powerful technique for the evaluation of flux control within biochemical pathways. Its foundation is the elasticity coefficients and the flux control coefficients (FCCs). On the basis of a thermokinetic description of reaction rates it is here shown...... that the elasticity coefficients can be calculated directly from the pool levels of metabolites at steady state. The only requirement is that one thermodynamic parameter be known, namely the reaction affinity at the intercept of the tangent in the inflection point of the curve of reaction rate against reaction...... of the thermokinetic description of reaction rates to include the influence of effecters. Here the reaction rate is written as a linear function of the logarithm of the metabolite concentrations. With this type of rate function it is shown that the approach of Delgado and Liao [Biochem. J. (1992) 282, 919-927] can...

Isobaric Tags for Relative and Absolute Quantitation-Based Proteomic Analysis of Patent and Constricted Ductus Arteriosus Tissues Confirms the Systemic Regulation of Ductus Arteriosus Closure.

Science.gov (United States)

Hong, Haifa; Ye, Lincai; Chen, Huiwen; Xia, Yu; Liu, Yue; Liu, Jinfen; Lu, Yanan; Zhang, Haibo

2015-08-01

We aimed to evaluate global changes in protein expression associated with patency by undertaking proteomic analysis of human constricted and patent ductus arteriosus (DA). Ten constricted and 10 patent human DAs were excised from infants with ductal-dependent heart disease during surgery. Using isobaric tags for relative and absolute quantitation-based quantitative proteomics, 132 differentially expressed proteins were identified. Of 132 proteins, voltage-gated sodium channel 1.3 (SCN3A), myosin 1d (Myo1d), Rho GTPase activating protein 26 (ARHGAP26), and retinitis pigmentosa 1 (RP1) were selected for validation by Western blot and quantitative real-time polymerase chain reaction analyses. Significant upregulation of SCN3A, Myo1d, and RP1 messenger RNA, and protein levels was observed in the patent DA group (all P ≤ 0.048). ARHGAP26 messenger RNA and protein levels were decreased in patent DA tissue (both P ≤ 0.018). Immunohistochemistry analysis revealed that Myo1d, ARHGAP26, and RP1 were specifically expressed in the subendothelial region of constricted DAs; however, diffuse expression of these proteins was noted in the patent group. Proteomic analysis revealed global changes in the expression of proteins that regulate oxygen sensing, ion channels, smooth muscle cell migration, nervous system, immune system, and metabolism, suggesting a basis for the systemic regulation of DA patency by diverse signaling pathways, which will be confirmed in further studies.

Ambient Mechanochemical Solid-State Reactions of Carbon Nanotubes and Their Reactions via Covalent Coordinate Bond in Solution

Science.gov (United States)

Kabbani, Mohamad A.

In its first part, this thesis deals with ambient mechanochemical solid-state reactions of differently functionalized multiple walled carbon nanotubes (MWCNTs) while in its second part it investigates the cross-linking reactions of CNTs in solution via covalent coordinate bonds with transitions metals and carboxylate groups decorating their surfaces. In the first part a series of mechanochemical reactions involving different reactive functionalities on the CNTs such as COOH/OH, COOH/NH2 and COCl/OH were performed. The solid-state unzipping of CNTs leading to graphene formation was confirmed using spectroscopic, thermal and electron microscopy techniques. The non-grapheme products were established using in-situ quadruple mass spectroscopy. The experimental results were confirmed by theoretical simulation calculations using the 'hot spots' protocol. The kinetics of the reaction between MWCNT-COOH and MWCNT-OH was monitored using variable temperature Raman spectroscopy. The low activation energy was discussed in terms of hydrogen bond mediated proton transfer mechanism. The second part involves the reaction of MWCNTII COOH with Zn (II) and Cu (II) to form CNT metal-organic frame (MOFs) products that were tested for their effective use as counter-electrodes in dyes sensitized solar cells (DSSC). The thesis concludes by the study of the room temperature reaction between the functionalized graphenes, GOH and G'-COOH followed by the application of compressive loads. The 3D solid graphene pellet product ( 0.6gm/cc) is conductive and reflective with a 35MPa ultimate strength as compared to 10MPa strength of graphite electrode ( 2.2gm/cc).

System of gait analysis based on ground reaction force assessment

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František Vaverka

2015-12-01

Full Text Available Background: Biomechanical analysis of gait employs various methods used in kinematic and kinetic analysis, EMG, and others. One of the most frequently used methods is kinetic analysis based on the assessment of the ground reaction forces (GRF recorded on two force plates. Objective: The aim of the study was to present a method of gait analysis based on the assessment of the GRF recorded during the stance phase of two steps. Methods: The GRF recorded with a force plate on one leg during stance phase has three components acting in directions: Fx - mediolateral, Fy - anteroposterior, and Fz - vertical. A custom-written MATLAB script was used for gait analysis in this study. This software displays instantaneous force data for both legs as Fx(t, Fy(t and Fz(t curves, automatically determines the extremes of functions and sets the visual markers defining the individual points of interest. Positions of these markers can be easily adjusted by the rater, which may be necessary if the GRF has an atypical pattern. The analysis is fully automated and analyzing one trial takes only 1-2 minutes. Results: The method allows quantification of temporal variables of the extremes of the Fx(t, Fy(t, Fz(t functions, durations of the braking and propulsive phase, duration of the double support phase, the magnitudes of reaction forces in extremes of measured functions, impulses of force, and indices of symmetry. The analysis results in a standardized set of 78 variables (temporal, force, indices of symmetry which can serve as a basis for further research and diagnostics. Conclusions: The resulting set of variable offers a wide choice for selecting a specific group of variables with consideration to a particular research topic. The advantage of this method is the standardization of the GRF analysis, low time requirements allowing rapid analysis of a large number of trials in a short time, and comparability of the variables obtained during different research measurements.

Meta-analysis to obtain a scale of psychological reaction after perinatal loss: focus on miscarriage

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Annsofie Adolfsson

2011-03-01

Full Text Available Annsofie Adolfsson1,21School of Life Sciences, University of Skövde, 2Department of Obstetrics and Gynecology, Skaraborg Hospital, Skövde, SwedenAbstract: Pregnancy has different meanings to different women depending upon their circumstances. A number of qualitative studies have described the experience of miscarriage by women who had desired to carry their pregnancy to full term. The aim of this meta-analysis was to identify a scale of psychological reaction to miscarriage. Meta-analysis is a quantitative approach for reviewing articles from scientific journals through statistical analysis of findings from individual studies. In this review, a meta-analytic method was used to identify and analyze psychological reactions in women who have suffered a miscarriage. Different reactions to stress associated with the period following miscarriage were identified. The depression reaction had the highest average, weighted, unbiased estimate of effect (d+ = 0.99 and was frequently associated with the experience of perinatal loss. Psychiatric morbidity was found after miscarriage in 27% of cases by a diagnostic interview ten days after miscarriage. The grief reaction had a medium d+ of 0.56 in the studies included. However, grief after miscarriage differed from other types of grief after perinatal loss because the parents had no focus for their grief. The guilt is greater after miscarriage than after other types of perinatal loss. Measurement of the stress reaction and anxiety reaction seems to be difficult in the included studies, as evidenced by a low d+ (0.17 and 0.16, respectively. It has been recommended that grief after perinatal loss be measured by an adapted instrument called the Perinatal Grief Scale Short Version.Keywords: psychological, perinatal loss, pregnancy, depression 

Reaction trajectory revealed by a joint analysis of protein data bank.

Science.gov (United States)

Ren, Zhong

2013-01-01

Structural motions along a reaction pathway hold the secret about how a biological macromolecule functions. If each static structure were considered as a snapshot of the protein molecule in action, a large collection of structures would constitute a multidimensional conformational space of an enormous size. Here I present a joint analysis of hundreds of known structures of human hemoglobin in the Protein Data Bank. By applying singular value decomposition to distance matrices of these structures, I demonstrate that this large collection of structural snapshots, derived under a wide range of experimental conditions, arrange orderly along a reaction pathway. The structural motions along this extensive trajectory, including several helical transformations, arrive at a reverse engineered mechanism of the cooperative machinery (Ren, companion article), and shed light on pathological properties of the abnormal homotetrameric hemoglobins from α-thalassemia. This method of meta-analysis provides a general approach to structural dynamics based on static protein structures in this post genomics era.

Reaction trajectory revealed by a joint analysis of protein data bank.

Directory of Open Access Journals (Sweden)

Zhong Ren

Full Text Available Structural motions along a reaction pathway hold the secret about how a biological macromolecule functions. If each static structure were considered as a snapshot of the protein molecule in action, a large collection of structures would constitute a multidimensional conformational space of an enormous size. Here I present a joint analysis of hundreds of known structures of human hemoglobin in the Protein Data Bank. By applying singular value decomposition to distance matrices of these structures, I demonstrate that this large collection of structural snapshots, derived under a wide range of experimental conditions, arrange orderly along a reaction pathway. The structural motions along this extensive trajectory, including several helical transformations, arrive at a reverse engineered mechanism of the cooperative machinery (Ren, companion article, and shed light on pathological properties of the abnormal homotetrameric hemoglobins from α-thalassemia. This method of meta-analysis provides a general approach to structural dynamics based on static protein structures in this post genomics era.

Thermodynamic analysis of dust sulphation reactions

Energy Technology Data Exchange (ETDEWEB)

Yang Yongxiang; Jokilaakso, A.

1997-12-31

Sulphation reactions of metal oxides with SO{sub 2} and O. or SO{sub 3} play significant roles in sulphation roasting of sulphide and oxide minerals as well as in desulphurisation process of combustion gases. In metallurgical waste-heat boilers for sulphide smelting, the sulphation of the oxidic flue dust in the atmosphere containing sulphur oxides is an unavoidable process, and the sulphation reactions have to be guided in a controlled way in the proper parts of the gas handling equipment. In this report, some thermodynamic analyses were conducted for the oxide sulphation reactions in relation to sulphide smelting processes. The phase stability of Me-S-O systems especially for oxides - sulphates equilibrium was studied under different thermodynamic conditions of gas compositions and temperatures. The sulphate stability was analysed for an example of gas compositions in the copper flash smelter of Outokumpu Harjavalta Metals Oy, in relation to temperature. In the report, most of the information was from literature. Moreover, a number of thermodynamic computations were carried out with the HSC program, and the constructed phase stability diagrams were compared with those from the literature whenever possible. The maximum temperatures for stable sulphates under normal operating conditions of the waste-heat boilers in sulphide smelting processes were obtained. This report will serve as the basis for the kinetic studies of the sulphation reactions and the sulphation reaction modelling in pyrometallurgical processes. (orig.) SULA 2 Programme. 36 refs.

Theoretical analysis of thermal molten metal-water reactions

International Nuclear Information System (INIS)

Schwalbe, W.

1982-01-01

In experiments with greater masses (kg-scale) two extreme cases had been oberved during the course of reaction when hot melt reacted with a vaporizable cooler liquid. Relatively mild hot interactions with slow pressure build-up and small pressure peak in the reaction volume often occurred but there were also some very violent reactions (steam explosions) where a remarkable portion of thermal energy had been transformed into mechanical energy with high pressure peaks. For the two types of reactions overall models for water as a coolant are developed here. Based on calculations and on comparisons with corresponding experiments it is shown that a relatively mild course of reaction can be explained by a fragmentation of the melt under following violent evaporation of the cooling medium. Pressures only with small reaction volumes up to the MPa range can be found in these reactions. The calculations, for example of Bird and Millington, showed a pressure maximum of 1 MPa after 170 ms of the start of the reaction; this agrees very well with the result of the experiment of 1.08 MPa. (orig./GL) [de

Dehydriding and rehydriding reactions of LiBH4

International Nuclear Information System (INIS)

Orimo, S.; Nakamori, Y.; Kitahara, G.; Miwa, K.; Ohba, N.; Towata, S.; Zuettel, A.

2005-01-01

Structural differences in LiBH 4 before and after the melting reaction at approximately 550-bar K were investigated to clarify the experimental method for the confirmation of reversible dehydriding and rehydriding reactions. Since the long-range order of LiBH 4 begins to disappear after the melting reaction was achieved, investigation of the atomistic vibrations of the [BH 4 ]-anion in LiBH 4 was found to be effective for the confirmation of the reversibility. In the present study, LiBH 4 was successively dehydrided (decomposed) into LiH and B under 1-bar MPa of hydrogen at 873-bar K, and then rehydrided (recombined) into LiBH 4 under 35-bar MPa of hydrogen at the same temperature (873-bar K). The temperatures at the beginning and ending of the dehydriding reaction are lowered, by approximately 30-bar K, for LiBH 4 substituted (or mixed) with Mg (atomic ratio of Li:Mg=9:1) as compared to those for LiBH 4 alone. This is similar to the tendency exhibited by LiNH 2

Antiadenoviral effects of N-chlorotaurine in vitro confirmed by quantitative polymerase chain reaction methods

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Eiichi Uchio

2010-11-01

Full Text Available Eiichi Uchio1, Hirotoshi Inoue1, Kazuaki Kadonosono21Department of Ophthalmology, Fukuoka University School of Medicine, Fukuoka, Japan; 2Department of Ophthalmology, Yokohama City University Medical Center, Yokohama, JapanPurpose: Adenoviral keratoconjunctivitis is recognized as one of the major pathogens of ophthalmological nosocomial infection worldwide. N-Chlorotaurine (Cl–HN–CH2–CH2–SO3H, NCT is the N-chloro derivative of the amino acid taurine, which is an oxidant produced by human granulocytes and monocytes during inflammatory reactions. Using conventional viral plaque assay, it was previously shown that NCT causes inactivation of several human adenovirus (HAdV serotypes. In this study, we evaluated the antiadenoviral effect of NCT by quantitative polymerase chain reaction (PCR methods.Methods: A549 cells were used for viral cell culture, and HAdV serotypes 3, 4, 8, 19, and 37 were used. After calculating 50% cytotoxic concentration (CC50 of NCT by MTS (3-(4,5-dimethylthiazol-2-yl-5-(3-carboxymethoxyphenyl-2-(4-sulfophenyl-2H-tetrazolium method, HAdV was cultured with NCT for 7 days, and extracted adenoviral DNA was quantitatively measured by real-time PCR.Results: A statistically significant (P < 0.05 dose-dependent inhibition was indicated for all serotypes except HAdV type 4 (HAdV4, which was maximally inhibited by only ~50%. Among the serotypes, NCT was particularly effective against HAdV8, HAdV19a, and HAdV37. The 50% effective concentration (EC50 obtained by real-time PCR of NCT ranged between 49 and 256 µM. EC50 of NCT against HAdV3 was slightly higher than that against serotypes of species D. The selective index (CC50/EC50 ranged between 41 and 60 except for HAdV4 (11.5.Conclusions: These results show that NCT has an antiviral effect against most serotypes of human HAdV inducing keratoconjunctivitis, indicating its possible therapeutic use.Keywords: adenovirus, N-chlorotaurine, epidemic keratoconjunctivitis, antiviral

MALDI MS-based Composition Analysis of the Polymerization Reaction of Toluene Diisocyanate (TDI) and Ethylene Glycol (EG).

Science.gov (United States)

Ahn, Yeong Hee; Lee, Yeon Jung; Kim, Sung Ho

2015-01-01

This study describes an MS-based analysis method for monitoring changes in polymer composition during the polyaddition polymerization reaction of toluene diisocyanate (TDI) and ethylene glycol (EG). The polymerization was monitored as a function of reaction time using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI TOF MS). The resulting series of polymer adducts terminated with various end-functional groups were precisely identified and the relative compositions of those series were estimated. A new MALDI MS data interpretation method was developed, consisting of a peak-resolving algorithm for overlapping peaks in MALDI MS spectra, a retrosynthetic analysis for the generation of reduced unit mass peaks, and a Gaussian fit-based selection of the most prominent polymer series among the reconstructed unit mass peaks. This method of data interpretation avoids errors originating from side reactions due to the presence of trace water in the reaction mixture or MALDI analysis. Quantitative changes in the relative compositions of the resulting polymer products were monitored as a function of reaction time. These results demonstrate that the mass data interpretation method described herein can be a powerful tool for estimating quantitative changes in the compositions of polymer products arising during a polymerization reaction.

Theoretical Study on Regioselectivity of the Diels-Alder Reaction between 1,8-Dichloroanthracene and Acrolein.

Science.gov (United States)

Sultan, Mujeeb A; Karama, Usama; Almansour, Abdulrahman I; Soliman, Saied M

2016-09-23

A theoretical study of the regioselectivity of the Diels-Alder reaction between 1,8-dichloroanthracene and acrolein is performed using DFT at the B3LYP/6-31G(d,p) level of theory. The FMO analysis, global and local reactivity indices confirmed the reported experimental results. Potential energy surface analysis showed that the cycloadditions (CAs) favor the formation of the anti product. These results are in good agreement with the reported results obtained experimentally where the anti is the major product.

Applications of the photo-nuclear reaction data for activation analysis

International Nuclear Information System (INIS)

Odsuren, M.; Khuukhenkhuu, G.; Turbold, A.; Davaa, S.; Baatarkhuu, D.

2015-01-01

In the relative method of activation analysis by continuum wide spectrum gamma-rays the same isotope is usually used for standard reference element and sample material in connection with different dependence of the reaction cross sections on the irradiation beam energy. But, in practice suitable isotopes for reference element are not always available. So, in this paper, we suggest a new method for photo-activation analysis in which is used the correction factor. This factor takes into account the difference in the photo-nuclear reaction cross section dependence on the gamma-ray energy for standard reference isotope and sample elements. The correction factor is determined by three methods of experimental, theoretical and TALYS evaluation. Pure metal foils of Au, Cu and Mo were irradiated by bremsstrahlung gamma-rays on the electron cyclic accelerator Microtron MT-22 at the Nuclear Research Center, National University of Mongolia. Gamma spectra of the activated metal foils were measured by HP-Ge detector to obtain element contents in the samples. It was shown that experimental results with correction factors are satisfactorily in agreement with real values of the element contents in the samples

Software news and update PyFrag - Streamlining your reaction path analysis

NARCIS (Netherlands)

van Zeist, W.-J.; Fonseca Guerra, C.; Bickelhaupt, F.M.

2008-01-01

The PyFrag program (released as PyFrag2007.01) is a "wrap-around" for the Amsterdam Density Functional (ADF) package and facilitates the extension of the fragment analysis method implemented in ADF along an entire potential energy surface. The purpose is to make analyses of reaction paths and other

Reaction Decoder Tool (RDT): extracting features from chemical reactions.

Science.gov (United States)

Rahman, Syed Asad; Torrance, Gilliean; Baldacci, Lorenzo; Martínez Cuesta, Sergio; Fenninger, Franz; Gopal, Nimish; Choudhary, Saket; May, John W; Holliday, Gemma L; Steinbeck, Christoph; Thornton, Janet M

2016-07-01

Extracting chemical features like Atom-Atom Mapping (AAM), Bond Changes (BCs) and Reaction Centres from biochemical reactions helps us understand the chemical composition of enzymatic reactions. Reaction Decoder is a robust command line tool, which performs this task with high accuracy. It supports standard chemical input/output exchange formats i.e. RXN/SMILES, computes AAM, highlights BCs and creates images of the mapped reaction. This aids in the analysis of metabolic pathways and the ability to perform comparative studies of chemical reactions based on these features. This software is implemented in Java, supported on Windows, Linux and Mac OSX, and freely available at https://github.com/asad/ReactionDecoder : asad@ebi.ac.uk or s9asad@gmail.com. © The Author 2016. Published by Oxford University Press.

Lab-on-a-chip based total-phosphorus analysis device utilizing a photocatalytic reaction

Science.gov (United States)

Jung, Dong Geon; Jung, Daewoong; Kong, Seong Ho

2018-02-01

A lab-on-a-chip (LOC) device for total phosphorus (TP) analysis was fabricated for water quality monitoring. Many commercially available TP analysis systems used to estimate water quality have good sensitivity and accuracy. However, these systems also have many disadvantages such as bulky size, complex pretreatment processes, and high cost, which limit their application. In particular, conventional TP analysis systems require an indispensable pretreatment step, in which the fluidic analyte is heated to 120 °C for 30 min to release the dissolved phosphate, because many phosphates are soluble in water at a standard temperature and pressure. In addition, this pretreatment process requires elevated pressures of up to 1.1 kg cm-2 in order to prevent the evaporation of the heated analyte. Because of these limiting conditions required by the pretreatment processes used in conventional systems, it is difficult to miniaturize TP analysis systems. In this study, we employed a photocatalytic reaction in the pretreatment process. The reaction was carried out by illuminating a photocatalytic titanium dioxide (TiO2) surface formed in a microfluidic channel with ultraviolet (UV) light. This pretreatment process does not require elevated temperatures and pressures. By applying this simplified, photocatalytic-reaction-based pretreatment process to a TP analysis system, greater degrees of freedom are conferred to the design and fabrication of LOC devices for TP monitoring. The fabricated LOC device presented in this paper was characterized by measuring the TP concentration of an unknown sample, and comparing the results with those measured by a conventional TP analysis system. The TP concentrations of the unknown sample measured by the proposed LOC device and the conventional TP analysis system were 0.018 mgP/25 mL and 0.019 mgP/25 mL, respectively. The experimental results revealed that the proposed LOC device had a performance comparable to the conventional bulky TP analysis

ANALYSIS OF A POSSIBLE REDUCTION IN ENERGY CONSUMPTION IN WATER ELECTROLYSIS REACTION

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Aurel George POPESCU

2013-05-01

Full Text Available It was experimentally observed that the electrolysis reaction continues a short period of time - time torelax c - after the cell power supply is interrupted. This paper presents an analysis of transient phenomenaoccurring and pr opose technical solutions

A novel CYBB mutation with the first genetically confirmed case of ...

African Journals Online (AJOL)

A case of a child with chronic granulomatous disease (CGD) presenting with recurrent mycobacterial infections and invasive Aspergillus fumigatus disease is described. Genetic analysis confirmed X-linked CGD with a novel mutation in exon 10 of the CYBB gene – the first South African report of genetically confirmed CGD.

Phylogenetic analysis and DNA-based species confirmation in Anopheles (Nyssorhynchus.

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Peter G Foster

Full Text Available Specimens of neotropical Anopheles (Nyssorhynchus were collected and identified morphologically. We amplified three genes for phylogenetic analysis-the single copy nuclear white and CAD genes, and the COI barcode region. Since we had multiple specimens for most species we were able to test how well the single or combined genes were able to corroborate morphologically defined species by placing the species into exclusive groups. We found that single genes, including the COI barcode region, were poor at confirming species, but that the three genes combined were able to do so much better. This has implications for species identification, species delimitation, and species discovery, and we caution that single genes are not enough. Higher level groupings were partially resolved with some well-supported groupings, whereas others were found to be either polyphyletic or paraphyletic. There were examples of known groups, such as the Myzorhynchella Section, which were poorly supported with single genes but were well supported with combined genes. From this we can infer that more sequence data will be needed in order to show more higher-level groupings with good support. We got unambiguously good support (0.94-1.0 Bayesian posterior probability from all DNA-based analyses for a grouping of An. dunhami with An. nuneztovari and An. goeldii, and because of this and because of morphological similarities we propose that An. dunhami be included in the Nuneztovari Complex. We obtained phylogenetic corroboration for new species which had been recognised by morphological differences; these will need to be formally described and named.

Confirmation Of Super Heavy Element Production In 48Ca Induced Fusion Reactions A Handshake Of Physics And Chemistry For Element 112

International Nuclear Information System (INIS)

Hofmann, S.; Ackermann, D.; Burkhard, H. G.; Heinz, S.; Hessberger, F. P.; Khuyagbaatar, J.; Kindler, B.; Kojouharov, I.; Lommel, B.; Mann, R.; Muenzenberg, G.; Schoett, H. J.; Sulignano, B.; Antalic, S.; Saro, S.; Streicher, B.; Venhart, M.; Yeremin, A. V.; Comas, V. F.; Heredia, J. A.

2008-01-01

The production of 283 112 in 48 Ca induced nuclear reactions was investigated using physical and chemical separation techniques. In the reaction 48 Ca on 238 U, four events were registered at the SHIP velocity filter. The mean atomic mass of the evaporation residues (EVR)

Assumption-free analysis of quantitative real-time polymerase chain reaction (PCR) data

NARCIS (Netherlands)

Ramakers, Christian; Ruijter, Jan M.; Deprez, Ronald H. Lekanne; Moorman, Antoon F. M.

2003-01-01

Quantification of mRNAs using real-time polymerase chain reaction (PCR) by monitoring the product formation with the fluorescent dye SYBR Green I is being extensively used in neurosciences, developmental biology, and medical diagnostics. Most PCR data analysis procedures assume that the PCR

RSA prediction of high failure rate for the uncoated Interax TKA confirmed by meta-analysis.

Science.gov (United States)

Pijls, Bart G; Nieuwenhuijse, Marc J; Schoones, Jan W; Middeldorp, Saskia; Valstar, Edward R; Nelissen, Rob G H H

2012-04-01

In a previous radiostereometric (RSA) trial the uncoated, uncemented, Interax tibial components showed excessive migration within 2 years compared to HA-coated and cemented tibial components. It was predicted that this type of fixation would have a high failure rate. The purpose of this systematic review and meta-analysis was to investigate whether this RSA prediction was correct. We performed a systematic review and meta-analysis to determine the revision rate for aseptic loosening of the uncoated and cemented Interax tibial components. 3 studies were included, involving 349 Interax total knee arthroplasties (TKAs) for the comparison of uncoated and cemented fixation. There were 30 revisions: 27 uncoated and 3 cemented components. There was a 3-times higher revision rate for the uncoated Interax components than that for cemented Interax components (OR = 3; 95% CI: 1.4-7.2). This meta-analysis confirms the prediction of a previous RSA trial. The uncoated Interax components showed the highest migration and turned out to have the highest revision rate for aseptic loosening. RSA appears to enable efficient detection of an inferior design as early as 2 years postoperatively in a small group of patients.

Theoretical Study on Regioselectivity of the Diels-Alder Reaction between 1,8-Dichloroanthracene and Acrolein

Directory of Open Access Journals (Sweden)

Mujeeb A. Sultan

2016-09-01

Full Text Available A theoretical study of the regioselectivity of the Diels-Alder reaction between 1,8-dichloroanthracene and acrolein is performed using DFT at the B3LYP/6-31G(d,p level of theory. The FMO analysis, global and local reactivity indices confirmed the reported experimental results. Potential energy surface analysis showed that the cycloadditions (CAs favor the formation of the anti product. These results are in good agreement with the reported results obtained experimentally where the anti is the major product.

Verification of the model of predisposition in triathlon – structural model of confirmative factor analysis

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Lenka Kovářová

2012-09-01

Full Text Available BACKGROUND: The triathlon is a combination of three different types of sport – swimming, cycling, and running. Each of these requires different top level predispositions and complex approach to talent selection is a rather difficult process. Attempts to identify assumptions in the triathlon have so far been specific and focused only on some groups of predispositions (physiology, motor tests, and psychology. The latest studies missed the structural approach and were based on determinants of sport performance, theory of sports training and expert assessment. OBJECTIVE: The aim of our study was to verify the model of predisposition in the short triathlon for talent assessment of young male athletes age 17–20 years. METHODS: The research sample consisted of 55 top level triathletes – men, who were included in the Government supported sports talent programme in the Czech Republic at the age of 17–20 years. We used a confirmative factor analysis (FA and Path diagram to verify the model, which allow us to explain mutual relationships among observed variables. For statistical data processing we used a structure equating modeling (SEM by software Lisrel L88. RESULTS: The study confirms best structural model for talent selection in triathlon at the age of 17–20 years old men, which composed seventeen indicators (tests and explained 91% of all cross-correlations (Goodness of Fit Index /GFI/ 0.91, Root Mean Square Residual /RMSR/ 0.13. Tests for predispositions in triathlons were grouped into five items, three motor predispositions (swimming, cycling and running skills, aerobic and psychological predispositions. Aerobic predispositions showed the highest importance to the assumptions to the general factor (1.00; 0. Running predispositions were measured as a very significant factor (–0.85; 0.28 which confirms importance of this critical stage of the race. Lower factor weight showed clusters of swimming (–0.61; 0.63 and cycling (0.53; 0

Analysis of the potential geochemical reactions in the Enceladus' hydrothermal environment

Science.gov (United States)

Ramirez-Cabañas, A. K.; Flandes, A.

2017-12-01

Enceladus is the sixth largest moon of Saturn and differs from its other moons, because of its cryovolcanic geysers that emanate from its south pole. The instruments of the Cassini spacecraft reveal different compounds in the gases and the dust of the geysers, such as salts (sodium chloride, sodium bicarbonate and/or sodium carbonate), as well as silica traces (Postberg et al., 2008, 2009) that could be the result of a hydrothermal environment (Hsu et al., 2014, Sekine et al., 2014). By means of a thermodynamic analysis, we propose and evaluate potential geochemical reactions that could happen from the interaction between the nucleus surface and the inner ocean of Enceladus. These reactions may well lead to the origin of the compounds found in the geysers. From this analysis, we propose that, at least, two minerals must be present in the condritic nucleus of Enceladus: olivines (fayalite and fosterite) and feldspar (orthoclase and albite). Subsequently, taking as reference the hydrothermal processes that take place on Earth, we propose the different stages of a potential hydrothermal scenario for Enceladus.

A Systematic Approach for the Design and Analysis of Reaction-Separation Systems with Recycle

DEFF Research Database (Denmark)

Gani, Rafiqul; Jimenez, Edgar Ramirez

2004-01-01

This paper presents a methodology for a systematic model-based analysis and the results obtained from it for an integrated design and analysis of reaction-separation systems with recycle. The methodology (systematic approach) consists of three stages where stage 1 identifies the limiting values...

Pathway confirmation and flux analysis of central metabolic pathways in Desulfovibrio vulgaris Hildenborough using Gas Chromatography-Mass Spectrometry and Fourier Transform-Ion Cyclotron Resonance Mass Spectrometry

International Nuclear Information System (INIS)

Tang, Yinjie; Pingitore, Francesco; Mukhopadhyay, Aindrila; Phan, Richard; Hazen, Terry C.; Keasling, Jay D.

2007-01-01

Flux distribution in central metabolic pathways of Desulfovibrio vulgaris Hildenborough was examined using 13C tracer experiments. Consistent with the current genome annotation and independent evidence from enzyme activity assays, the isotopomer results from both GC-MS and Fourier Transform-Ion Cyclotron Resonance mass spectrometry (FT-ICR MS) indicate the lack of oxidatively functional TCA cycle and an incomplete pentose phosphate pathway. Results from this study suggest that fluxes through both pathways are limited to biosynthesis. The data also indicate that >80 percent of the lactate was converted to acetate and the reactions involved are the primary route of energy production (NAD(P)H and ATP production). Independent of the TCA cycle, direct cleavage of acetyl-CoA to CO and 5,10-methyl-THF also leads to production of NADH and ATP. Although the genome annotation implicates a ferredoxin-dependent oxoglutarate synthase, isotopic evidence does not support flux through this reaction in either the oxidative or reductive mode; therefore, the TCA cycle is incomplete. FT-ICR MS was used to locate the labeled carbon distribution in aspartate and glutamate and confirmed the presence of an atypical enzyme for citrate formation suggested in previous reports (the citrate synthesized by this enzyme is the isotopic antipode of the citrate synthesized by the (S)-citrate synthase). These findings enable a better understanding of the relation between genome annotation and actual metabolic pathways in D. vulgaris, and also demonstrate FT-ICR MS as a powerful tool for isotopomer analysis, overcoming problems in both GC-MS and NMR spectroscopy

Analysis of the effects of reaction parameters upon the molecular weight of an aromatic poly(hydrazide) through experimental design

International Nuclear Information System (INIS)

Gomes, Dominique; Pinto, Jose Carlos; Borges, Cristiano P.; Nunes, Suzana P.

2001-01-01

Samples of an aromatic poly(hydrazide) were synthesized through low temperature solution polycondensation reactions. Monomers were characterized by nuclear magnetic resonance (NMR) and thermal analysis. The polymer material was characterized by intrinsic viscosity measurements and by NMR. The thermal behavior of the polymer samples was studied by thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC). The effect of various factors that influence the course of the polymerization reaction, such as concentration of monomer and electrolyte (LiCl) in the reaction medium, purity of the monomers, reaction temperature and reaction time, were investigated. Reaction conditions were then optimized in order to allow the preparation of high molecular weight polymer resins. Values of intrinsic viscosity obtained for the poly(hydrazide) in N-methyl-2-pyrrolidone were as high as 1.51 dL/g. (author)

Characterization of materials eliciting foreign body reaction in stapled human gastrointestinal anastomoses.

Science.gov (United States)

Lim, C B B; Goldin, R D; Darzi, A; Hanna, G B

2008-08-01

Staples are made of titanium, which elicits minimal tissue reaction. The authors have encountered foreign body reaction associated with stapled human gastrointestinal anastomoses, although the literature has no reports of this. The aim of this study was to identify the refractile foreign materials causing this reaction. Histological sections were taken from 14 gastrointestinal specimens from patients with a history of a stapled anastomosis within the specimen excised. These were reviewed by light and polarization microscopy. Scanning electron microscopy and energy dispersive X-ray analysis were carried out on these sections, staples and stapler cartridges used for gastrointestinal surgery. Foreign bodies rich in fluorine were found in three patients, and those rich in carbon in 12. Other elements identified included oxygen, calcium, sodium, potassium, magnesium, aluminium and silicon. One specimen was found to contain titanium with no surrounding foreign body reaction. Stapler cartridges contained carbon, oxygen, fluorine, calcium, sodium, potassium, magnesium, aluminium, silicon and traces of titanium. Staples were composed of pure titanium with some fibrous material on the surface containing elements found in stapler cartridges. The presence of foreign body reaction was confirmed in stapled human gastrointestinal anastomoses. The source of refractile materials eliciting this reaction was the stapler cartridges. (c) 2008 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.

Stationary patterns in star networks of bistable units: Theory and application to chemical reactions.

Science.gov (United States)

Kouvaris, Nikos E; Sebek, Michael; Iribarne, Albert; Díaz-Guilera, Albert; Kiss, István Z

2017-04-01

We present theoretical and experimental studies on pattern formation with bistable dynamical units coupled in a star network configuration. By applying a localized perturbation to the central or the peripheral elements, we demonstrate the subsequent spreading, pinning, or retraction of the activations; such analysis enables the characterization of the formation of stationary patterns of localized activity. The results are interpreted with a theoretical analysis of a simplified bistable reaction-diffusion model. Weak coupling results in trivial pinned states where the activation cannot propagate. At strong coupling, a uniform state is expected with active or inactive elements at small or large degree networks, respectively. A nontrivial stationary spatial pattern, corresponding to an activation pinning, is predicted to occur at an intermediate number of peripheral elements and at intermediate coupling strengths, where the central activation of the network is pinned, but the peripheral activation propagates toward the center. The results are confirmed in experiments with star networks of bistable electrochemical reactions. The experiments confirm the existence of the stationary spatial patterns and the dependence of coupling strength on the number of peripheral elements for transitions between pinned and retreating or spreading fronts in forced network configurations (where the central or periphery elements are forced to maintain their states).

Bifurcation Analysis of Gene Propagation Model Governed by Reaction-Diffusion Equations

Directory of Open Access Journals (Sweden)

Guichen Lu

2016-01-01

Full Text Available We present a theoretical analysis of the attractor bifurcation for gene propagation model governed by reaction-diffusion equations. We investigate the dynamical transition problems of the model under the homogeneous boundary conditions. By using the dynamical transition theory, we give a complete characterization of the bifurcated objects in terms of the biological parameters of the problem.

Serpentinization reaction pathways: implications for modeling approach

Energy Technology Data Exchange (ETDEWEB)

Janecky, D.R.

1986-01-01

Experimental seawater-peridotite reaction pathways to form serpentinites at 300/sup 0/C, 500 bars, can be accurately modeled using the EQ3/6 codes in conjunction with thermodynamic and kinetic data from the literature and unpublished compilations. These models provide both confirmation of experimental interpretations and more detailed insight into hydrothermal reaction processes within the oceanic crust. The accuracy of these models depends on careful evaluation of the aqueous speciation model, use of mineral compositions that closely reproduce compositions in the experiments, and definition of realistic reactive components in terms of composition, thermodynamic data, and reaction rates.

Cumulative BRCA mutation analysis in the Greek population confirms that homogenous ethnic background facilitates genetic testing.

Science.gov (United States)

Tsigginou, Alexandra; Vlachopoulos, Fotios; Arzimanoglou, Iordanis; Zagouri, Flora; Dimitrakakis, Constantine

2015-01-01

Screening for BRCA 1 and BRCA 2 mutations has long moved from the research lab to the clinic as a routine clinical genetic testing. BRCA molecular alteration pattern varies among ethnic groups which makes it already a less straightforward process to select the appropriate mutations for routine genetic testing on the basis of known clinical significance. The present report comprises an in depth literature review of the so far reported BRCA 1 and BRCA 2 molecular alterations in Greek families. Our analysis of Greek cumulative BRCA 1 and 2 molecular data, produced by several independent groups, confirmed that six recurrent deleterious mutations account for almost 60 % and 70 % of all BRCA 1 and 2 and BRCA 1 mutations, respectively. As a result, it makes more sense to perform BRCA mutation analysis in the clinic in two sequential steps, first conventional analysis for the six most prevalent pathogenic mutations and if none identified, a second step of New Generation Sequencing-based whole genome or whole exome sequencing would follow. Our suggested approach would enable more clinically meaningful, considerably easier and less expensive BRCA analysis in the Greek population which is considered homogenous.

Interfacial reactions in intermetallic matrix composites

International Nuclear Information System (INIS)

Cantrell, L.B.; Clevenger, E.M.; Perepezko, J.H.

1993-01-01

The thermal stability of advanced composites is dominated by the behavior of internal interfaces. Analysis of these internal interfaces often involves consideration of at least ternary order phase equilibria. Limited thermodynamic data exists for ternary and higher order systems. However, a combined approach based upon the use of binary data to estimate ternary phase equilibria and experimentally determined reaction pathways is effective in the analysis of interface reactions in composite systems. In blended powder samples, thermal analysis was used to find possible reaction temperatures, while X-ray analysis, EDS, and EPMA of diffusion couples were used to assess interdiffusion reaction pathways. The approach is illustrated by compatibility studies between TiAl and TiSi 2 at 1,100 C, and in-situ reactions between B 4 C and TiAl at 1300 C where multiple reaction sequences have been analyzed to provide guidance for the design of in-situ reaction processing of composites

Mining chemical reactions using neighborhood behavior and condensed graphs of reactions approaches.

Science.gov (United States)

de Luca, Aurélie; Horvath, Dragos; Marcou, Gilles; Solov'ev, Vitaly; Varnek, Alexandre

2012-09-24

This work addresses the problem of similarity search and classification of chemical reactions using Neighborhood Behavior (NB) and Condensed Graphs of Reaction (CGR) approaches. The CGR formalism represents chemical reactions as a classical molecular graph with dynamic bonds, enabling descriptor calculations on this graph. Different types of the ISIDA fragment descriptors generated for CGRs in combination with two metrics--Tanimoto and Euclidean--were considered as chemical spaces, to serve for reaction dissimilarity scoring. The NB method has been used to select an optimal combination of descriptors which distinguish different types of chemical reactions in a database containing 8544 reactions of 9 classes. Relevance of NB analysis has been validated in generic (multiclass) similarity search and in clustering with Self-Organizing Maps (SOM). NB-compliant sets of descriptors were shown to display enhanced mapping propensities, allowing the construction of better Self-Organizing Maps and similarity searches (NB and classical similarity search criteria--AUC ROC--correlate at a level of 0.7). The analysis of the SOM clusters proved chemically meaningful CGR substructures representing specific reaction signatures.

Optimizing Nuclear Reaction Analysis (NRA) using Bayesian Experimental Design

International Nuclear Information System (INIS)

Toussaint, Udo von; Schwarz-Selinger, Thomas; Gori, Silvio

2008-01-01

Nuclear Reaction Analysis with 3 He holds the promise to measure Deuterium depth profiles up to large depths. However, the extraction of the depth profile from the measured data is an ill-posed inversion problem. Here we demonstrate how Bayesian Experimental Design can be used to optimize the number of measurements as well as the measurement energies to maximize the information gain. Comparison of the inversion properties of the optimized design with standard settings reveals huge possible gains. Application of the posterior sampling method allows to optimize the experimental settings interactively during the measurement process.

Analysis of trace gases at ppb levels by proton transfer reaction mass spectrometry (PTR-MS)

International Nuclear Information System (INIS)

Lindinger, W.; Hansel, A.

1996-01-01

A proton transfer reaction mass spectrometry (PTR-MS) system has been developed which allows for on-line measurements of trace gas components with concentrations as low as 1 ppb. The method is based on reactions of H 3 O + ions, which perform non-dissociative proton transfer to most of the common organic trace constituents but do not react with any of the components present in clean air. Examples of medical information obtained by means of breath analysis, of environmental trace analysis, and examples in the field of food chemistry demonstrate the wide applicability of the method. (Authors)

Factors associated with child sexual abuse confirmation at forensic examinations

Directory of Open Access Journals (Sweden)

Welington dos Santos Silva

Full Text Available Abstract The aim of this study is identify potential factors associated with child sexual abuse confirmation at forensic examinations. The forensic files of children under 12 years of age reporting sexual abuse at the Nina Rodrigues Institute of Forensic Medicine in Salvador, Bahia, Brazil between January 2008 and December 2009 were reviewed. A multivariate analysis was conducted to identify factors associated with finding evidence of sexual abuse in forensic examinations. The proportion of cases confirmed by the forensic physician based on material evidence was 10.4%. Adjusted analysis showed that the variables place of birth, type of abuse reported, family relationship between the child and the perpetrator, and the interval between the reported abuse and the forensic examination were not independently associated with finding forensic evidence of sexual abuse. A report of penetration was associated with a five-fold greater likelihood of confirmation, while the victim being 10-11 years of age was associated with a two-fold of abuse confirmation than younger children. These findings should be taken into consideration when drawing up guidelines for the multidisciplinary evaluation of children suspected of being victims of sexual abuse and in deciding whether to refer the child for forensic examination.

Steady-state isotopic transient kinetic analysis investigation of CO-O2 and CO-NO reactions over a commercial automotive catalyst

International Nuclear Information System (INIS)

Oukaci, R.; Blackmond, D.G.; Goodwin, J.G. Jr.; Gallaher, G.R.

1992-01-01

In this paper, steady-state isotopic transient kinetic analysis (SSITKA) is used to study two model reactions, CO oxidation and CO-NO reactions, on a typical formulation of a three-way auto-catalyst. Under steady-state conditions, abrupt switches in the isotopic composition of CO ( 12 C 16 O/ 13 C 18 O) were carried out to produce isotopic transients in both labeled reactants and products. Along with the determination of the average surface lifetimes and concentrations of reaction intermediates, an analysis of the transient responses along the carbon reaction pathway indicated that the distribution of active sites for the formation of CO 2 was bimodal for both reactions. Furthermore, relatively few surface sites contributed to the overall reaction rate

Compositional analysis of silicon nitride films on Si and GaAs by backscattering spectrometry and nuclear resonance reaction analysis

International Nuclear Information System (INIS)

Kumar, Sanjiv; Raju, V.S.

2004-01-01

This paper describes the application of proton and α-backscattering spectrometry for the determination of atomic ratio of Si to N in 1100-5000 A silicon nitride films on Si and GaAs. The conventional α-Rutherford backscattering spectrometry is suitable for the analysis of films on Si; it is rather inadequate for films on GaAs due to higher background from the substrate. It is shown that these films can be analysed by 14 N(α,α) 14 N scattering with 3.5 MeV α-particles. Proton elastic scattering with enhanced cross sections for 28 Si(p,p) 28 Si and 14 N(p,p) 14 N scatterings, is also suitable for analysing films on GaAs. However, the analysis of films on Si by this technique is difficult due to interferences between the signals of Si from the film and the substrate. In addition, the hydrogen content in films is determined by 1 H( 19 F,αγ) 16 O nuclear reaction analysis using the resonance at 6.4 MeV. The combination of backscattering spectrometry with nuclear reaction analysis provides compositional analysis of ternary Si 1-(x+y) N x H y films

Sedation for pediatric radiological procedures: analysis of potential causes of sedation failure and paradoxical reactions

International Nuclear Information System (INIS)

Karian, V.E.; Burrows, P.E.; Connor, L.; Zurakowski, D.; Mason, K.P.

1999-01-01

Background. Sedation for diagnostic imaging and interventional radiologic procedures in pediatrics has greatly increased over the past decade. With appropriate patient selection and monitoring, serious adverse effects are infrequent, but failure to sedate and paradoxical reactions do occur. Objective. The purpose of this study was to determine, among patients undergoing sedation for radiologic procedures, the incidence of sedation failure and paradoxical reaction to pentobarbital and to identify potentially correctable causes. Materials and methods. Records of 1665 patients who were sedated in the radiology department from 1 November 1997 to 1 July 1998 were reviewed. Patients failing sedation or experiencing paradoxical reaction were compared with respect to sex, age group, diagnosis, scan type, time of day, NPO status, use of IV contrast and type of sedation agent using the Fisher exact test, Pearson chi-square, analysis of variance (ANOVA), the Student t-test, and logistic regression. Results. Data analysis revealed a sedation failure rate of 1 % and paradoxical reaction rate of 1.2 %. Stepwise multiple logistic regression revealed that the only significant independent multivariate predictor of failure was the need for the administration of a combination of pentobarbital, fentanyl, and midazolam IV. Conclusion. The low rate of sedation failure and paradoxical reactions to pentobarbital was near optimal and probably cannot be improved with the currently available sedatives. (orig.)

Sedation for pediatric radiological procedures: analysis of potential causes of sedation failure and paradoxical reactions

Energy Technology Data Exchange (ETDEWEB)

Karian, V.E.; Burrows, P.E.; Connor, L. [Dept. of Radiology, Children' s Hospital, Boston, MA (United States); Zurakowski, D. [Dept. of Biostatistics, Children' s Hospital, Boston, MA (United States); Mason, K.P. [Dept. of Anesthesiology, Children' s Hospital, Boston, MA (United States)

1999-11-01

Background. Sedation for diagnostic imaging and interventional radiologic procedures in pediatrics has greatly increased over the past decade. With appropriate patient selection and monitoring, serious adverse effects are infrequent, but failure to sedate and paradoxical reactions do occur. Objective. The purpose of this study was to determine, among patients undergoing sedation for radiologic procedures, the incidence of sedation failure and paradoxical reaction to pentobarbital and to identify potentially correctable causes. Materials and methods. Records of 1665 patients who were sedated in the radiology department from 1 November 1997 to 1 July 1998 were reviewed. Patients failing sedation or experiencing paradoxical reaction were compared with respect to sex, age group, diagnosis, scan type, time of day, NPO status, use of IV contrast and type of sedation agent using the Fisher exact test, Pearson chi-square, analysis of variance (ANOVA), the Student t-test, and logistic regression. Results. Data analysis revealed a sedation failure rate of 1 % and paradoxical reaction rate of 1.2 %. Stepwise multiple logistic regression revealed that the only significant independent multivariate predictor of failure was the need for the administration of a combination of pentobarbital, fentanyl, and midazolam IV. Conclusion. The low rate of sedation failure and paradoxical reactions to pentobarbital was near optimal and probably cannot be improved with the currently available sedatives. (orig.)

Molecular-dynamics analysis of mobile helium cluster reactions near surfaces of plasma-exposed tungsten

Energy Technology Data Exchange (ETDEWEB)

Hu, Lin; Maroudas, Dimitrios, E-mail: maroudas@ecs.umass.edu [Department of Chemical Engineering, University of Massachusetts, Amherst, Massachusetts 01003-9303 (United States); Hammond, Karl D. [Department of Chemical Engineering, University of Missouri, Columbia, Missouri 65211 (United States); Wirth, Brian D. [Department of Nuclear Engineering, University of Tennessee, Knoxville, Tennessee 37996 (United States)

2015-10-28

We report the results of a systematic atomic-scale analysis of the reactions of small mobile helium clusters (He{sub n}, 4 ≤ n ≤ 7) near low-Miller-index tungsten (W) surfaces, aiming at a fundamental understanding of the near-surface dynamics of helium-carrying species in plasma-exposed tungsten. These small mobile helium clusters are attracted to the surface and migrate to the surface by Fickian diffusion and drift due to the thermodynamic driving force for surface segregation. As the clusters migrate toward the surface, trap mutation (TM) and cluster dissociation reactions are activated at rates higher than in the bulk. TM produces W adatoms and immobile complexes of helium clusters surrounding W vacancies located within the lattice planes at a short distance from the surface. These reactions are identified and characterized in detail based on the analysis of a large number of molecular-dynamics trajectories for each such mobile cluster near W(100), W(110), and W(111) surfaces. TM is found to be the dominant cluster reaction for all cluster and surface combinations, except for the He{sub 4} and He{sub 5} clusters near W(100) where cluster partial dissociation following TM dominates. We find that there exists a critical cluster size, n = 4 near W(100) and W(111) and n = 5 near W(110), beyond which the formation of multiple W adatoms and vacancies in the TM reactions is observed. The identified cluster reactions are responsible for important structural, morphological, and compositional features in the plasma-exposed tungsten, including surface adatom populations, near-surface immobile helium-vacancy complexes, and retained helium content, which are expected to influence the amount of hydrogen re-cycling and tritium retention in fusion tokamaks.

Field theory of propagating reaction-diffusion fronts

International Nuclear Information System (INIS)

Escudero, C.

2004-01-01

The problem of velocity selection of reaction-diffusion fronts has been widely investigated. While the mean-field limit results are well known theoretically, there is a lack of analytic progress in those cases in which fluctuations are to be taken into account. Here, we construct an analytic theory connecting the first principles of the reaction-diffusion process to an effective equation of motion via field-theoretic arguments, and we arrive at results already confirmed by numerical simulations

Combined analysis of data from two granddaughter designs: A simple strategy for QTL confirmation and increasing experimental power in dairy cattle

Directory of Open Access Journals (Sweden)

Blümel Jürgen

2003-05-01

Full Text Available Abstract A joint analysis of five paternal half-sib Holstein families that were part of two different granddaughter designs (ADR- or Inra-design was carried out for five milk production traits and somatic cell score in order to conduct a QTL confirmation study and to increase the experimental power. Data were exchanged in a coded and standardised form. The combined data set (JOINT-design consisted of on average 231 sires per grandsire. Genetic maps were calculated for 133 markers distributed over nine chromosomes. QTL analyses were performed separately for each design and each trait. The results revealed QTL for milk production on chromosome 14, for milk yield on chromosome 5, and for fat content on chromosome 19 in both the ADR- and the Inra-design (confirmed within this study. Some QTL could only be mapped in either the ADR- or in the Inra-design (not confirmed within this study. Additional QTL previously undetected in the single designs were mapped in the JOINT-design for fat yield (chromosome 19 and 26, protein yield (chromosome 26, protein content (chromosome 5, and somatic cell score (chromosome 2 and 19 with genomewide significance. This study demonstrated the potential benefits of a combined analysis of data from different granddaughter designs.

Pyrrole PMOs, incorporating new N-heterocyclic compounds on an ethene-PMO through Diels–Alder reactions

International Nuclear Information System (INIS)

Esquivel, Dolores; De Canck, Els; Jiménez-Sanchidrián, César; Romero-Salguero, Francisco J.; Van Der Voort, Pascal

2014-01-01

The ethenylene bridges on the walls of an ethenylene-bridged periodic mesoporous organosilica were successfully modified with a variety of pyrrole derivatives – pyrrole, methylpyrrole, dimethylpyrrole, trimethylpyrrole and 1-phenylpyrrole – through Diels–Alder reactions. X-ray diffraction measurements and N 2 adsorption–desorption analysis confirmed the preservation of the ordering and mesoporosity of the parent material as well as the decoration of the pores with the surface Diels–Alder adducts. Moreover, other techniques such as DRIFT, 13 C and 29 Si nuclear magnetic resonances revealed the formation of the surface N-heterocyclic compounds at the parent ethenylene sites. - Highlights: • Chemical modification of the double bonds on an ethene-PMO through the Diels–Alder reaction. • A family of pyrrole derivatives act as dienes in the Diels–Alder reaction. • Well-ordering and mesoporosity are retained after the post-functionalization. • N-containing compounds on the surface of ethene-PMO are present after the Diels–Alder reaction

Pyrrole PMOs, incorporating new N-heterocyclic compounds on an ethene-PMO through Diels–Alder reactions

Energy Technology Data Exchange (ETDEWEB)

Esquivel, Dolores; De Canck, Els [Center for Ordered Materials, Organometallics and Catalysis, Department of Inorganic and Physical Chemistry, Ghent University, Krijgslaan 281-S3, 9000 Ghent (Belgium); Jiménez-Sanchidrián, César [Department of Organic Chemistry, Nanochemistry and Fine Chemistry Research Institute (IUIQFN), Faculty of Sciences, University of Córdoba, Campus de Rabanales, Marie Curie Building, Ctra. Nnal. IV, km 396, 14071 Córdoba (Spain); Romero-Salguero, Francisco J., E-mail: qo2rosaf@uco.es [Department of Organic Chemistry, Nanochemistry and Fine Chemistry Research Institute (IUIQFN), Faculty of Sciences, University of Córdoba, Campus de Rabanales, Marie Curie Building, Ctra. Nnal. IV, km 396, 14071 Córdoba (Spain); Van Der Voort, Pascal, E-mail: pascal.vandervoort@ugent.be [Center for Ordered Materials, Organometallics and Catalysis, Department of Inorganic and Physical Chemistry, Ghent University, Krijgslaan 281-S3, 9000 Ghent (Belgium)

2014-11-14

The ethenylene bridges on the walls of an ethenylene-bridged periodic mesoporous organosilica were successfully modified with a variety of pyrrole derivatives – pyrrole, methylpyrrole, dimethylpyrrole, trimethylpyrrole and 1-phenylpyrrole – through Diels–Alder reactions. X-ray diffraction measurements and N{sub 2} adsorption–desorption analysis confirmed the preservation of the ordering and mesoporosity of the parent material as well as the decoration of the pores with the surface Diels–Alder adducts. Moreover, other techniques such as DRIFT, {sup 13}C and {sup 29}Si nuclear magnetic resonances revealed the formation of the surface N-heterocyclic compounds at the parent ethenylene sites. - Highlights: • Chemical modification of the double bonds on an ethene-PMO through the Diels–Alder reaction. • A family of pyrrole derivatives act as dienes in the Diels–Alder reaction. • Well-ordering and mesoporosity are retained after the post-functionalization. • N-containing compounds on the surface of ethene-PMO are present after the Diels–Alder reaction.

Preparation of nano-aluminum and studies on thermo-reaction properties

International Nuclear Information System (INIS)

Wei Sheng; Wang Chaoyang; Huang Yong; Wu Weidong; Tang Yongjian; Wei Jianjun

2002-01-01

The author presents the fabrication of nano-aluminum powders by evaporation-condensation method. The thermo gravimetric-differential scanning calorimetry technique is used to characterize the thermo-reaction properties between nano-aluminum powders and N 2 or Ar. The experiment results confirm the different thermo-reaction properties between block- and nano-aluminum

Applications of Nuclear Reaction Analysis for Semiconductor Industry

International Nuclear Information System (INIS)

Wei Luncun

2003-01-01

Many thin film samples used in the semiconductor industry contain C, N and O. The detection limits and accuracy obtained by Rutherford Backscattering Spectroscopy (RBS) measurement are limited due to the small cross section values. High energy non-Rutherford backscattering is often used to enhance the sensitivities. But non-Rutherford cross section values are irregular and can not be calculated as normal Rutherford backscattering values. It is also difficult to find an appropriate energy window that for all these elements, and high-energy ions are needed. In this paper, the Nuclear Reaction Analysis (NRA) method is used to simultaneously measure C, N and O. several applications in the semiconductor research, development, and manufacturing areas are presented

Analysis of agility, reaction time and balance variables at badminton players aged 9-14 years

Directory of Open Access Journals (Sweden)

Seydi Ahmet Ağaoğlu

2017-12-01

Full Text Available Aim: The aim of this study was investigated agility, static and dynamic balance and reaction time variables of badminton players aged between 9-14 and relate with among variables. Material and Methods: In Samsun, 19 males (sport age, 3.42±1.64 years and 12 females (3.00±1.28 years active badminton players were voluntarily participated in who are in 9-14 ages range. Agility was measured by “T” test, CSMI-Tecnobody Pk-252 isokinetic balance system measuring instrument was used to test static balance and dynamic balance and Mozart Lafayette reaction measuring instrument was used to test visual and auditory reaction times of players. Spearman correlation analysis was applied so as to correlation analysis. The level of significance was taken as p<0.05. Results: For female athletes, a positive relation was determined between the agility and the perimeter (mm used (r=0.727; p<0.01 through the static balance measure double foot and eyes are open. For male athletes, a positive relation was determined between the visual reaction time and the perimeter (mm used (r=0.725; p<0.01 through the static balance measure dominant foot and eyes are open. For male and female athletes were not found any correlation between reaction time and dynamic balance. Conclusion: It was determined that audio (ears and visual (eyes reaction time was effective on balance. While badminton players are closed eyes, audio sensors are more influence on balance test through measure dominant foot.

Analysis of reaction products of food contaminants and ingredients: bisphenol A diglycidyl ether (BADGE) in canned foods.

Science.gov (United States)

Coulier, Leon; Bradley, Emma L; Bas, Richard C; Verhoeckx, Kitty C M; Driffield, Malcolm; Harmer, Nick; Castle, Laurence

2010-04-28

Bisphenol A diglycidyl ether (BADGE) is an epoxide that is used as a starting substance in the manufacture of can coatings for food-contact applications. Following migration from the can coating into food, BADGE levels decay and new reaction products are formed by reaction with food ingredients. The significant decay of BADGE was demonstrated by liquid chromatographic (LC) analysis of foodstuffs, that is, tuna, apple puree, and beer, spiked with BADGE before processing and storage. Life-science inspired analytical approaches were successfully applied to study the reactions of BADGE with food ingredients, for example, amino acids and sugars. An improved mass balance of BADGE was achieved by selective detection of reaction products of BADGE with low molecular weight food components, using a successful combination of stable isotopes of BADGE and analysis by LC coupled to fluorescence detection (FLD) and high-resolution mass spectrometric (MS) detection. Furthermore, proteomics approaches showed that BADGE also reacts with peptides (from protein digests in model systems) and with proteins in foods. The predominant reaction center for amino acids, peptides, and proteins was cysteine.

Analysis of the consequences of 'thermite' reaction

International Nuclear Information System (INIS)

Yorio, Daniel; Cincotta, Daniel O.; Camacho, Esteban F.; Bruno, Hernan R.; Boero, Norma L.

1999-01-01

The mixture of Al-U 3 O 8 is not in a state of chemical equilibrium, and at temperatures of between 850 degree C and 1000 degree C, it reacts exo thermally. This is known, in corresponding bibliography, as a 'Thermite reaction'. This mixture is used in the manufacturing of the plate-type fuel used in research reactors. It has been pointed out that the release of energy caused by this type of reactions might represent a risk in case of accidents in this type of reactor. Conclusions, in general, tend to indicate that no such risk exists, although no concrete assurance is given that this is the case, and this fact, therefore, leaves room for doubt. The objective of this paper is to provide an in-depth study of what happens to a fuel plate when it is subjected to thermite reaction. We will, furthermore, analyze the consequences of the release of energy generated by this type of reaction within the core of the reactor, clearly defining the problem for this type of fuel and this kind of reactor

Evidence for fluctuations in statistical model cross sections from the study of {sup 27}Al(d,{alpha}) {sup 25}Mg reaction; Mise en evidence des fluctuations de sections efficaces du modele statistique par l'etude de la reaction {sup 27}Al(d,{alpha}) {sup 25}Mg

Energy Technology Data Exchange (ETDEWEB)

Papineau born Heller, L [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1965-06-01

A complete set of experimental data has been obtained for the reaction {sup 27}Al(d, {alpha}){sup 25}Mg for excitation energies in the compound nucleus {sup 29}Si between 19.7 and 27.4 MeV, in order to compare with the theoretical predictions of the statistical model of nuclear reactions including fluctuations. Numerical calculations of the theoretical cross sections were made and contributions to methods of analysis of fluctuating excitation functions are given. The results confirm strong evidence for statistical fluctuations in nuclear cross sections. (author) [French] On a obtenu un ensemble complet de donnees experimentales de la reaction {sup 27}Al(d, {alpha}){sup 25}Mg pour des energies d'excitation du noyau compose {sup 29}Si comprises entre 19,7 et 27,4 MeV, permettant la comparaison avec les previsions theoriques du modele statistique des reactions nucleaires dans sa version complete comprenant les fluctuations. Des calculs numeriques de sections efficaces theoriques ont ete effectues et des contributions ont ete apportees aux methodes d'analyse de fonctions d'excitation presentant des fluctuations. Les resultats ont clairement confirme l'existence de fluctuations statistiques de sections efficaces. (auteur)

Synthesis and characterization of an octaimidazolium-based polyhedral oligomeric silsesquioxanes ionic liquid by an ion-exchange reaction.

Science.gov (United States)

Tan, Jinglin; Ma, Depeng; Sun, Xingrong; Feng, Shengyu; Zhang, Changqiao

2013-04-07

Preparation of POSS-min-DS, an octaimidazolium-based polyhedral oligomeric silsesquioxanes (POSS) room temperature ionic liquid, by an ion-exchange reaction between POSS and sodium dodecyl sulfate was reported. Octaimidazolium-based POSS was synthesized with more than 98% yield within 3 h. POSS-min-DS and octaimidazolium-based POSS were confirmed by (1)H, (13)C, and (29)Si NMR, FT-IR and elemental analysis.

Quantitative Analysis of Homogeneous Electrocatalytic Reactions at IDA Electrodes: The Example of [Ni(PPh2NBn2)2]2+

Energy Technology Data Exchange (ETDEWEB)

Liu, Fei; Parkinson, B. A.; Divan, Ralu; Roberts, John; Liang, Yanping

2016-12-01

Interdigitated array (IDA) electrodes have been applied to study the EC’ (electron transfer reaction followed by a catalytic reaction) reactions and a new method of quantitative analysis of IDA results was developed. In this new method, currents on IDA generator and collector electrodes for an EC’ mechanism are derived from the number of redox cycles and the contribution of non-catalytic current. And the fractions of bipotential recycling species and catalytic-active species are calculated, which helps understanding the catalytic reaction mechanism. The homogeneous hydrogen evolution reaction catalyzed by [Ni(PPh2NBn2)2]2+ (where PPh2NBn2 is 1,5-dibenzyl-3,7-diphenyl-1,5-diaza-3,7-diphosphacyclooctane) electrocatalyst was examined and analyzed with IDA electrodes. Besides, the existence of reaction intermediates in the catalytic cycle is inferred from the electrochemical behavior of a glassy carbon disk electrodes and carbon IDA electrodes. This quantitative analysis of IDA electrode cyclic voltammetry currents can be used as a simple and straightforward method for determining reaction mechanism in other catalytic systems as well.

Quantitative Analysis of Homogeneous Electrocatalytic Reactions at IDA Electrodes: The Example of [Ni(PPh2NBn2)2]2+

International Nuclear Information System (INIS)

Liu, Fei; Parkinson, B.A.; Divan, Ralu; Roberts, John; Liang, Yanping

2016-01-01

Interdigitated array (IDA) electrodes have been applied to study the EC’ (electron transfer reaction followed by a catalytic reaction) reactions and a new method of quantitative analysis of IDA results was developed. In this new method, currents on IDA generator and collector electrodes for an EC’ mechanism are derived from the number of redox cycles and the contribution of non-catalytic current. And the fractions of bipotential recycling species and catalytic-active species are calculated, which helps understanding the catalytic reaction mechanism. The homogeneous hydrogen evolution reaction catalyzed by [Ni(P Ph 2 N Bn 2 ) 2 ] 2+ (where P Ph 2 N Bn 2 is 1,5-dibenzyl-3,7-diphenyl-1,5-diaza-3,7-diphosphacyclooctane) electrocatalyst was examined and analyzed with IDA electrodes. Besides, the existence of reaction intermediates in the catalytic cycle is inferred from the electrochemical behavior of a glassy carbon disk electrodes and carbon IDA electrodes. This quantitative analysis of IDA electrode cyclic voltammetry currents can be used as a simple and straightforward method for determining reaction mechanism in other catalytic systems as well.

Confirmation of a novel siadenovirus species detected in raptors: partial sequence and phylogenetic analysis.

Science.gov (United States)

Kovács, Endre R; Benko, Mária

2009-03-01

Partial genome characterisation of a novel adenovirus, found recently in organ samples of multiple species of dead birds of prey, was carried out by sequence analysis of PCR-amplified DNA fragments. The virus, named as raptor adenovirus 1 (RAdV-1), has originally been detected by a nested PCR method with consensus primers targeting the adenoviral DNA polymerase gene. Phylogenetic analysis with the deduced amino acid sequence of the small PCR product has implied a new siadenovirus type present in the samples. Since virus isolation attempts remained unsuccessful, further characterisation of this putative novel siadenovirus was carried out with the use of PCR on the infected organ samples. The DNA sequence of the central genome part of RAdV-1, encompassing nine full (pTP, 52K, pIIIa, III, pVII, pX, pVI, hexon, protease) and two partial (DNA polymerase and DBP) genes and exceeding 12 kb pairs in size, was determined. Phylogenetic tree reconstructions, based on several genes, unambiguously confirmed the preliminary classification of RAdV-1 as a new species within the genus Siadenovirus. Further study of RAdV-1 is of interest since it represents a rare adenovirus genus of yet undetermined host origin.

Continuous optical measurement system of hemolysis during a photosensitization reaction using absorption spectrum

Science.gov (United States)

Hamada, R.; Ogawa, E.; Arai, T.

2018-02-01

To investigate hemolysis phenomena during a photosensitization reaction with the reaction condition continuously and simultaneously for a safety assessment of hemolysis side effect, we constructed an optical system to measure blood sample absorption spectrum during the reaction. Hemolysis degree might be under estimated in general evaluation methods because there is a constant oxygen pressure assumption in spite of oxygen depression take place. By investigating hemoglobin oxidation and oxygen desorption dynamics obtained from the contribution of the visible absorption spectrum and multiple regression analysis, both the hemolysis phenomena and its oxygen environment might be obtained with time. A 664 nm wavelength laser beam for the reaction excitation and 475-650 nm light beam for measuring the absorbance spectrum were arranged perpendicularly crossing. A quartz glass cuvette with 1×10 mm in dimensions for the spectrum measurement was located at this crossing point. A red blood cells suspension medium was arranged with low hematocrit containing 30 μg/ml talaporfin sodium. This medium was irradiated up to 40 J/cm2 . The met-hemoglobin, oxygenatedhemoglobin, and deoxygenated-hemoglobin concentrations were calculated by a multiple regression analysis from the measured spectra. We confirmed the met-hemoglobin concentration increased and oxygen saturation decreased with the irradiation time, which seems to indicate the hemolysis progression and oxygen consumption, respectively. By using our measuring system, the hemolysis progression seems to be obtained with oxygen environment information.

[Rapid screening and confirmation of 205 pesticide residues in rice by QuEChERS and liquid chromatography-mass spectrometry].

Science.gov (United States)

Chen, Xi; Cheng, Lei; Qu, Shichao; Huang, Daliang; Liu, Jiacheng; Cui, Han; Jia, Yanbo; Ji, Mingshan

2015-10-01

A method for rapid screening and confirmation of 205 pesticide residues in rice was developed by combining QuEChERS and high performance liquid chromatography-triple quadrupole-linear ion trap mass spectrometry (LC-Q-TRAP/MS). The rice samples were extracted with acetonitrile, and then cleaned up with primary secondary amine (PSA), anhydrous magnesium sulfate (MgSO4) and C18 adsorbent. Finally, the samples were detected by LC-Q-TRAP/MS in multiple reaction monitoring with information-dependent acquisition of enhanced product ion (MRM-IDA-EPI) mode followed with database searching. A total of 205 pesticide residues were confirmed by retention times, ion pairs and the database searching using EPI library, and quantified by external standard method. All the pesticides showed good linearities with linear correlation coefficients all above 0.995. The limits of quantification (LOQs) for the 205 pesticides were 0.5-10.0 μg/kg. The average recoveries of the 205 pesticides ranged from 62.4% to 127.1% with the relative standard deviations (RSDs) of 1.0% - 20.0% at spiked levels of 10 μg/kg and 50 μg/kg, and only 20 min were needed for the analysis of an actual rice sample. In brief, the method is fast, accurate and highly sensitive, and is suitable for the screening and confirmation of pesticide residues in rice.

Global Controllability of Chemical Reactions

OpenAIRE

Drexler, Dániel András; Tóth, János

2015-01-01

Controllability of chemical reactions is an important problem in chemical engineering science. In control theory, analysis of the controllability of linear systems is well-founded, however the dynamics of chemical reactions is usually nonlinear. Global controllability properties of chemical reactions are analyzed here based on the Lie-algebra of the vector fields associated to elementary reactions. A chemical reaction is controllable almost everywhere if all the reaction rate coefficients can...

Cintichem modified process - {sup 99}Mo precipitation step: application of statistical analysis tools over the reaction parameters

Energy Technology Data Exchange (ETDEWEB)

Teodoro, Rodrigo; Dias, Carla R.B.R.; Osso Junior, Joao A., E-mail: jaosso@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Fernandez Nunez, Eutimio Gustavo [Universidade de Sao Paulo (EP/USP), SP (Brazil). Escola Politecnica. Dept. de Engenharia Quimica

2011-07-01

Precipitation of {sup 99}Mo by {alpha}-benzoin oxime ({alpha}-Bz) is a standard precipitation method for molybdenum due the high selectivity of this agent. Nowadays, statistical analysis tools have been employed in analytical systems to prove its efficiency and feasibility. IPEN has a project aiming the production of {sup 99}Mo by the fission of {sup 235}U route. The processing uses as the first step the precipitation of {sup 99}Mo with {alpha}-Bz. This precipitation step involves many key reaction parameters. The aim of this work is based on the development of the already known acidic route to produce {sup 99}Mo as well as the optimization of the reactional parameters applying statistical tools. In order to simulate {sup 99}Mo precipitation, the study was conducted in acidic media using HNO{sub 3}, {alpha}Bz as precipitant agent and NaOH /1%H{sub 2}O{sub 2} as dissolver solution. Then, a Mo carrier, KMnO{sub 4} solutions and {sup 99}Mo tracer were added to the reaction flask. The reactional parameters ({alpha}-Bz/Mo ratio, Mo carrier, reaction time and temperature, and cooling reaction time before filtration) were evaluated under a fractional factorial design of resolution V. The best values of each reactional parameter were determined by a response surface statistical planning. The precipitation and recovery yields of {sup 99}Mo were measured using HPGe detector. Statistical analysis from experimental data suggested that the reactional parameters {alpha}-Bz/Mo ratio, reaction time and temperature have a significant impact on {sup 99}Mo precipitation. Optimization statistical planning showed that higher {alpha}Bz/Mo ratios, room temperature, and lower reaction time lead to higher {sup 99}Mo yields. (author)

Stability Analysis of a Reaction-Diffusion System Modeling Atherogenesis

KAUST Repository

Ibragimov, Akif

2010-01-01

This paper presents a linear, asymptotic stability analysis for a reaction-diffusionconvection system modeling atherogenesis, the initiation of atherosclerosis, as an inflammatory instability. Motivated by the disease paradigm articulated by Ross, atherogenesis is viewed as an inflammatory spiral with a positive feedback loop involving key cellular and chemical species interacting and reacting within the intimal layer of muscular arteries. The inflammatory spiral is initiated as an instability from a healthy state which is defined to be an equilibrium state devoid of certain key inflammatory markers. Disease initiation is studied through a linear, asymptotic stability analysis of a healthy equilibrium state. Various theorems are proved, giving conditions on system parameters guaranteeing stability of the health state, and a general framework is developed for constructing perturbations from a healthy state that exhibit blow-up, which are interpreted as corresponding to disease initiation. The analysis reveals key features that arterial geometry, antioxidant levels, and the source of inflammatory components (through coupled third-kind boundary conditions or through body sources) play in disease initiation. © 2010 Society for Industrial and Applied Mathematics.

Detection and quantification of Renibacterium salmoninarum DNA in salmonid tissues by real-time quantitative polymerase chain reaction analysis

Science.gov (United States)

Chase, D.M.; Elliott, D.G.; Pascho, R.J.

2006-01-01

Renibacterium salmoninarum is an important salmonid pathogen that is difficult to culture. We developed and assessed a real-time, quantitative, polymerase chain reaction (qPCR) assay for the detection and enumeration of R. salmoninarum. The qPCR is based on TaqMan technology and amplifies a 69-base pair (bp) region of the gene encoding the major soluble antigen (MSA) of R. salmoninarum. The qPCR assay consistently detected as few as 5 R. salmoninarum cells per reaction in kidney tissue. The specificity of the qPCR was confirmed by testing the DNA extracts from a panel of microorganisms that were either common fish pathogens or reported to cause false-positive reactions in the enzyme-linked immunosorbent assay (ELISA). Kidney samples from 38 juvenile Chinook salmon (Oncorhynchus tshawytscha) in a naturally infected population were examined by real-time qPCR, a nested PCR, and ELISA, and prevalences of R. salmoninarum detected were 71, 66, and 71%, respectively. The qPCR should be a valuable tool for evaluating the R. salmoninarum infection status of salmonids.

Simplified method of ''push-pull'' test data analysis for determining in situ reaction rate coefficients

International Nuclear Information System (INIS)

Haggerty, R.; Schroth, M.H.; Istok, J.D.

1998-01-01

The single-well, ''''push-pull'''' test method is useful for obtaining information on a wide variety of aquifer physical, chemical, and microbiological characteristics. A push-pull test consists of the pulse-type injection of a prepared test solution into a single monitoring well followed by the extraction of the test solution/ground water mixture from the same well. The test solution contains a conservative tracer and one or more reactants selected to investigate a particular process. During the extraction phase, the concentrations of tracer, reactants, and possible reaction products are measured to obtain breakthrough curves for all solutes. This paper presents a simplified method of data analysis that can be used to estimate a first-order reaction rate coefficient from these breakthrough curves. Rate coefficients are obtained by fitting a regression line to a plot of normalized concentrations versus elapsed time, requiring no knowledge of aquifer porosity, dispersivity, or hydraulic conductivity. A semi-analytical solution to the advective-dispersion equation is derived and used in a sensitivity analysis to evaluate the ability of the simplified method to estimate reaction rate coefficients in simulated push-pull tests in a homogeneous, confined aquifer with a fully-penetrating injection/extraction well and varying porosity, dispersivity, test duration, and reaction rate. A numerical flow and transport code (SUTRA) is used to evaluate the ability of the simplified method to estimate reaction rate coefficients in simulated push-pull tests in a heterogeneous, unconfined aquifer with a partially penetrating well. In all cases the simplified method provides accurate estimates of reaction rate coefficients; estimation errors ranged from 0.1 to 8.9% with most errors less than 5%

Confirmation of the absolute configuration of (−)-aurantioclavine

KAUST Repository

Behenna, Douglas C.

2011-04-01

We confirm our previous assignment of the absolute configuration of (-)-aurantioclavine as 7R by crystallographically characterizing an advanced 3-bromoindole intermediate reported in our previous synthesis. This analysis also provides additional support for our model of enantioinduction in the palladium(II)-catalyzed oxidative kinetic resolution of secondary alcohols. © 2010 Elsevier Ltd. All rights reserved.

Analysis of the fuel influence in obtaining HAp by combustion reaction

International Nuclear Information System (INIS)

Santos, T.L.; Leite, A.M.D.; Viana, K.M.S.

2016-01-01

The search for new materials for biomedical applications has led to investigation of the calcium phosphate bioceramics, and in particular hydroxyapatite (HAp), being a material similar to bone tissue, with excellent biocompatibility and high osteoconduction, enabling bone regeneration which allows the use at implants and prostheses. The synthesis of the nanometric HAp by combustion reaction enables obtaining the nanometric HAp with a more similar structure biological apatite as possible. This work aims to synthesize HAp by combustion reaction using two different routes of synthesis, first, using urea as fuel and the second using glycine, after this, evaluate the influence of fuels used in the microstructure of the hydroxyapatite obtained. The HAp obtained was characterized by: XRD, FTIR and SEM. Through analysis of the results, there is the synthesis conditions used that glycine has performed more favorable to obtaining HAp. (author)

Modelling and simulation of a transketolase mediated reaction: Sensitivity analysis of kinetic parameters

DEFF Research Database (Denmark)

Sayar, N.A.; Chen, B.H.; Lye, G.J.

2009-01-01

In this paper we have used a proposed mathematical model, describing the carbon-carbon bond format ion reaction between beta-hydroxypyruvate and glycolaldehyde to synthesise L-erythrulose, catalysed by the enzyme transketolase, for the analysis of the sensitivity of the process to its kinetic...

Modeling and analysis of liquid deuterium-water reactions

International Nuclear Information System (INIS)

Taleyarkhan, R.P.

1995-01-01

This Presentation highlights the following: Overview of LD 2 -water reactions their connections to research reactors with cold sources; some key features and ingredients of vapor explosions in general; Examination of results of 1970 experiment at Grenoble Nuclear Research Center; Thermodynamic evaluations of energetics of explosive LD 2 -D 2 O reactions. This presentation concentrates only on the technical aspects of LD 2 /LH 2 - water reactions; it is not intended to draw/imply safety-related conclusions for research reactors

Comparative Analysis of Clinical Samples Showing Weak Serum Reaction on AutoVue System Causing ABO Blood Typing Discrepancies

OpenAIRE

Jo, Su Yeon; Lee, Ju Mi; Kim, Hye Lim; Sin, Kyeong Hwa; Lee, Hyeon Ji; Chang, Chulhun Ludgerus; Kim, Hyung-Hoi

2016-01-01

Background ABO blood typing in pre-transfusion testing is a major component of the high workload in blood banks that therefore requires automation. We often experienced discrepant results from an automated system, especially weak serum reactions. We evaluated the discrepant results by the reference manual method to confirm ABO blood typing. Methods In total, 13,113 blood samples were tested with the AutoVue system; all samples were run in parallel with the reference manual method according to...

Resonance search on πN reaction

International Nuclear Information System (INIS)

Sugahara, Ryuhei

1974-01-01

Present status of the study on resonance state is reviewed. Among various problems on the resonance state, the inelastic decay of baryon resonance and boson resonance are described in this paper. Experimental data on N → N eta with bubble chambers are few. An experimental results by using a counter shows enhancement around 1.8 GeV in the relation between cross section and energy. Some bubble chamber experiment also shows enhancement around 1.6 GeV. The spin and parity analyses for 1000 events are required. Data on N → Nω show enhancement at 1.76 GeV. The effective mass distribution on N → delta ++ (1236)π + π - shows enhancement around 2.0 GeV. Study on the boson resonance has been made, but still ambiguity remains. Effective mass distribution on the reaction π + d → pspπ + π - π 0 shows a peak of ω 1664 . The assignment of spin and parity by Matthews et al. is not in agreement with that by Kenyon et al. therefore confirmation by other experiment is necessary. A few experiment show peaks at 1.4 and 1.7 GeV in the effective mass distribution of (rho 0 rho 0 ) in the reaction anti pp → 3π + π - . Confirmation is also required. Deviation was found in the effective mass distribution of (ωπ + π - ) in anti pp → 3π + π - π 0 reaction, and ωπ + π - decay was seen in π + d → psp2π + 2π - π 0 reaction. (Kato, T.)

Large scale international replication and meta-analysis study confirms association of the 15q14 locus with myopia. The CREAM consortium

NARCIS (Netherlands)

Verhoeven, Virginie J. M.; Hysi, Pirro G.; Saw, Seang-Mei; Vitart, Veronique; Mirshahi, Alireza; Guggenheim, Jeremy A.; Cotch, Mary Frances; Yamashiro, Kenji; Baird, Paul N.; Mackey, David A.; Wojciechowski, Robert; Ikram, M. Kamran; Hewitt, Alex W.; Duggal, Priya; Janmahasatian, Sarayut; Khor, Chiea-Chuen; Fan, Qiao; Zhou, Xin; Young, Terri L.; Tai, E.-Shyong; Goh, Liang-Kee; Li, Yi-Ju; Aung, Tin; Vithana, Eranga; teo, Yik-Ying; Tay, Wanting; Sim, Xueling; Rudan, Igor; Hayward, Caroline; Wright, Alan F.; Polasek, Ozren; Campbell, Harry; Wilson, James F.; Fleck, Brian W.; Nakata, Isao; Yoshimura, Nagahisa; Yamada, Ryo; Matsuda, Fumihiko; Ohno-Matsui, Kyoko; Nag, Abhishek; McMahon, George; St Pourcain, Beate; Lu, Yi; Rahi, Jugnoo S.; Cumberland, Phillippa M.; Bhattacharya, Shomi; Simpson, Claire L.; Atwood, Larry D.; Li, Xiaohui; Raffel, Leslie J.; Murgia, Federico; Portas, Laura; Despriet, Dominiek D. G.; van Koolwijk, Leonieke M. E.; Wolfram, Christian; Lackner, Karl J.; Tönjes, Anke; Mägi, Reedik; Lehtimäki, Terho; Kähönen, Mika; Esko, Tõnu; Metspalu, Andres; Rantanen, Taina; Pärssinen, Olavi; Klein, Barbara E.; Meitinger, Thomas; Spector, Timothy D.; Oostra, Ben A.; Smith, Albert V.; de Jong, Paulus T. V. M.; Hofman, Albert; Amin, Najaf; Karssen, Lennart C.; Rivadeneira, Fernando; Vingerling, Johannes R.; Eiríksdóttir, Guðný; Gudnason, Vilmundur; Döring, Angela; Bettecken, Thomas; Uitterlinden, André G.; Williams, Cathy; Zeller, Tanja; Castagné, Raphaële; Oexle, Konrad; van Duijn, Cornelia M.; Iyengar, Sudha K.; Mitchell, Paul; Wang, Jie Jin; Höhn, René; Pfeiffer, Norbert; Bailey-Wilson, Joan E.; Stambolian, Dwight; Wong, Tien-Yin; Hammond, Christopher J.; Klaver, Caroline C. W.

2012-01-01

Myopia is a complex genetic disorder and a common cause of visual impairment among working age adults. Genome-wide association studies have identified susceptibility loci on chromosomes 15q14 and 15q25 in Caucasian populations of European ancestry. Here, we present a confirmation and meta-analysis

Studies in the reaction dynamics of beam-gas chemiluminescent reactions

International Nuclear Information System (INIS)

Prisant, M.G.

1984-01-01

This thesis develops techniques for the analysis and interpretation of data obtained from beam-gas chemiluminescence experiments. These techniques are applied to experimental studies of atom transfer reactions of the type A + BC → AB + C. A procedure is developed for determining the product rotational alignment in the center-of-mass frame from polarization measurements of chemiluminescent atom-diatom exchange reactions under beam-gas conditions. Knowledge of a vector property of a reaction, such as product alignment, provides information on the disposition of angular momentum by a chemical reaction. Fluorescence polarization and hence product alignment are measured for two prototype reactions. The reaction of metastable calcium atoms with hydrogen-chloride gas yields highly aligned calcium-chloride product which exhibits little variation of alignment with vibrational state. The reaction of ground-state calcium with fluorine gas yields moderately aligned product which shows strong variation of alignment with vibration. A multi-surface direct-interaction model is developed to interpret product alignment and population data. The predictions of this model for the reaction of calcium with fluorine show reasonable agreement with experiment

Study of the He3 breakup reaction and the triton production spectra at 283 MeV

International Nuclear Information System (INIS)

Hussain Obid, R.

1988-01-01

The breakup of He3 ions at 94MeV/nucleon was studied in inclusive experiments on nuclei ranging from C12 to Pb208, and in coincidence experiments (γd) and (γt) on an A127 target. The inclusive spectra of protons and deuterons show an important contribution of the He3 breakup reaction to the reaction cross section (80%). Analysis of the dependence as a function of A confirms a peripheral mechanism. The coincidence experiment gives a proportion of inelastic breakup in the inclusive cross section of 40 %. Examination of triton spectra reveals that at 94 MeV the dominant reaction is not breakup transfer as at lower energies, but charge exchange. The spectra peak at energies of 20MeV, compatible with the excitation of a mixture of L=1 and L=2 states. The variation of the cross section following an A 1/3 law indicates a peripheral mechanism for the (He3,t) reaction too. The (γ-t) coincidence reaction showing residual nucleus production near the target nucleus reinforces this result [fr

Development of analysis model for mid and long-term effects of sodium water reaction event in LMR

International Nuclear Information System (INIS)

Eoh, Jae Hyuk; Sim, Yoon Sub; Kim, Seong O; Kim, Yeon Sik; Kim, Eui Kwang; Wi, Myung Hwan

2002-04-01

The Sodium-Water Reaction(SWR) is important in the design consideration of a LMR steam generator. To develop the analysis code for long-term effects of SWR, investigation on the characteristics of various SWR analysis code and the assessment of an analysis model for long term effects were performed. In an event of SWR, pressure spikes of wave propagation occur at its initial stage and last for a very short time, and then bulk motion of fluid and reaction products is progressed and lasts for a long time. In a case SWR occurs, a number of hydrogen bubbles produced and sodium is entrained into the bubbles through the gas-liquid bubble interfaces by evaporation or diffusion. The partial pressure of the sodium in a hydrogen bubble is determined as a function of the bubble size, temperature, and pressure, and is rapidly decreased as its size increased. From this, it can be considered that the bulk motion in the later phase of SWR is an axial motion caused by expansion of a single-phase hydrogen gas bubble produced by a reaction in the vicinity of the leak site. Through this investigation, a preliminary simple analysis model for long-term effects of SWR was set up and sensitivity study using the system design parameters such as pressure and temperature of IHTS for KALIMER was performed. Also, a simpler analysis model using the cover gas pressure change related to the production of a hydrogen bubble in a steam generator was developed from the analyses results. These simple analysis models of the reaction site and the pressure behavior with hydrogen production can be used to develop the mid and long-term analysis code for SWR in the KALIMER steam generator design

Evaluation of reactor induced (n,p) reactions for activation analysis of titanium in geological materials

Energy Technology Data Exchange (ETDEWEB)

Espinosa Garcia, R; Cohen, I M [Comision Nacional de Energia Atomica, Buenos Aires (Argentina)

1984-05-01

The possibilities of reactor induced (n,p) reactions as a tool for neutron activation analysis of titanium in geological samples are discussed. The interference of calcium and scandium is experimentally evaluated. Results for Ti, Ca and Sc in GSP-1 and PCC-1 standard rocks are presented. Based on the experimental values, it is concluded that the /sup 47/Ti(n,p)/sup 47/Sc reaction is the most favourable for titanium determination. 11 refs.

Silica functionalized Cu(II) acetylacetonate Schiff base complex: An efficient catalyst for the oxidative condensation reaction of benzyl alcohol with amines

Science.gov (United States)

Anbarasu, G.; Malathy, M.; Karthikeyan, P.; Rajavel, R.

2017-09-01

Silica functionalized Cu(II) acetylacetonate Schiff base complex via the one pot reaction of silica functionalized 3-aminopropyltriethoxysilane with acetyl acetone and copper acetate has been reported. The synthesized material was well characterized by analytical techniques such as FT-IR, UV-DRS, XRD, SEM-EDX, HR-TEM, EPR, ICP-AES and BET analysis. The characterization results confirmed the grafting of Cu(II) Schiff base complex on the silica surface. The catalytic activity of synthesized silica functionalized Cu(II) acetylacetonate Schiff base complex was evaluated through the oxidative condensation reaction of benzyl alcohol to imine.

Utilization of thin-layer chromatography for confirmational sampling during remedial excavation

International Nuclear Information System (INIS)

Burton, P.J.

1996-01-01

Thin-layer chromatography (TLC) is a simple, efficient, inexpensive, and accurate method of chemical analysis. This method is applicable to field testing for confirming the limits of excavation during excavation of petroleum, oil, and/or lubricant (POL) contamination. Traditionally, excavation at contaminated sites suffers from a time delay due to the need to obtain laboratory confirmation of the limits of excavation. All suspected contaminated material is removed for stockpiling or remediation. The remaining soils need to be sampled to confirm that no contaminated material remains in the excavation. The site scientist collects samples and sends them out for analysis at a certified laboratory. The laboratory requires, even for a rush order, several days to analyze the samples. This time delay interferes with the efficiency of the operation. The excavations either have to be left open (which is a safety hazard) or reopened if additional material must be excavated. TLC samples can be collected and analyzed in several hours allowing for a short turnaround time for analytical results. The TLC method can be easily performed by a technician. Results of a case study from a subarctic Alaskan site will be reported. Simple operational TLC procedures will be shared. The equipment required for TLC analysis will be outlined. Correlation data between TLC and laboratory analysis will be presented

Applications of nuclear reaction analysis for determining hydrogen and deuterium distribution in metals

International Nuclear Information System (INIS)

Altstetter, C.J.

1981-01-01

The use of ion beams for materials analysis has made a successful transition from the domain of the particle physicist to that of the materials scientist. The subcategory of this field, nuclear reaction analysis, is just now undergoing the transition, particularly in applications to hydrogen in materials. The materials scientist must locate the nearest accelerator, because now he will find that using it can solve mysteries that do not yield to other techniques. 9 figures

Analysis of Brownian Dynamics Simulations of Reversible Bimolecular Reactions

KAUST Repository

Lipková, Jana

2011-01-01

A class of Brownian dynamics algorithms for stochastic reaction-diffusion models which include reversible bimolecular reactions is presented and analyzed. The method is a generalization of the λ-bcȳ model for irreversible bimolecular reactions which was introduced in [R. Erban and S. J. Chapman, Phys. Biol., 6(2009), 046001]. The formulae relating the experimentally measurable quantities (reaction rate constants and diffusion constants) with the algorithm parameters are derived. The probability of geminate recombination is also investigated. © 2011 Society for Industrial and Applied Mathematics.

Reaction theories for N* excitations in πN and γN reactions

International Nuclear Information System (INIS)

Lee, T.S.H.

1996-01-01

The importance of developing reaction theories for investigating N* physics is illustrated in an analysis of pion photoproduction on the nucleon. It is shown that the γN ↔ Δ transition amplitudes predicted by the constituent quark model are in agreement with the values extracted from the γN → πN data only when the contributions from the reaction mechanisms calculated using a dynamical approach are taken into account in the analysis

The improvement of the heat transfer model for sodium-water reaction jet code

International Nuclear Information System (INIS)

Hashiguchi, Yoshirou; Yamamoto, Hajime; Kamoshida, Norio; Murata, Shuuichi

2001-02-01

For confirming the reasonable DBL (Design Base Leak) on steam generator (SG), it is necessary to evaluate phenomena of sodium-water reaction (SWR) in an actual steam generator realistically. The improvement of a heat transfer model on sodium-water reaction (SWR) jet code (LEAP-JET ver.1.40) and application analysis to the water injection tests for confirmation of propriety for the code were performed. On the improvement of the code, the heat transfer model between a inside fluid and a tube wall was introduced instead of the prior model which was heat capacity model including both heat capacity of the tube wall and inside fluid. And it was considered that the fluid of inside the heat exchange tube was able to treat as water or sodium and typical heat transfer equations used in SG design were also introduced in the new heat transfer model. Further additional work was carried out in order to improve the stability of the calculation for long calculation time. The test calculation using the improved code (LEAP-JET ver.1.50) were carried out with conditions of the SWAT-IR·Run-HT-2 test. It was confirmed that the SWR jet behavior on the result and the influence to the result of the heat transfer model were reasonable. And also on the improved code (LEAP-JET ver.1.50), user's manual was revised with additional I/O manual and explanation of the heat transfer model and new variable name. (author)

Characterising Complex Enzyme Reaction Data.

Directory of Open Access Journals (Sweden)

Handan Melike Dönertaş

Full Text Available The relationship between enzyme-catalysed reactions and the Enzyme Commission (EC number, the widely accepted classification scheme used to characterise enzyme activity, is complex and with the rapid increase in our knowledge of the reactions catalysed by enzymes needs revisiting. We present a manual and computational analysis to investigate this complexity and found that almost one-third of all known EC numbers are linked to more than one reaction in the secondary reaction databases (e.g., KEGG. Although this complexity is often resolved by defining generic, alternative and partial reactions, we have also found individual EC numbers with more than one reaction catalysing different types of bond changes. This analysis adds a new dimension to our understanding of enzyme function and might be useful for the accurate annotation of the function of enzymes and to study the changes in enzyme function during evolution.

Structure of fungal oxyluciferin, the product of the bioluminescence reaction.

Science.gov (United States)

Purtov, K V; Osipova, Z M; Petushkov, V N; Rodionova, N S; Tsarkova, A S; Kotlobay, A A; Chepurnykh, T V; Gorokhovatsky, A Yu; Yampolsky, I V; Gitelson, J I

2017-11-01

The structure of fungal oxyluciferin was determined, the enzymatic bioluminescence reaction under substrate saturation conditions with discrete monitoring of formed products was conducted, and the structures of the end products of the reaction were established. On the basis of these studies, the scheme of oxyluciferin degradation to the end products was developed. The structure of fungal oxyluciferin was confirmed by counter synthesis.

Collection of human reaction times and supporting health related data for analysis of cognitive and physical performance

Directory of Open Access Journals (Sweden)

Petr Brůha

2018-04-01

Full Text Available Smoking, excessive drinking, overeating and physical inactivity are well-established risk factors decreasing human physical performance. Moreover, epidemiological work has identified modifiable lifestyle factors, such as poor diet and physical and cognitive inactivity that are associated with the risk of reduced cognitive performance. Definition, collection and annotation of human reaction times and suitable health related data and metadata provides researchers with a necessary source for further analysis of human physical and cognitive performance. The collection of human reaction times and supporting health related data was obtained from two groups comprising together 349 people of all ages - the visitors of the Days of Science and Technology 2016 held on the Pilsen central square and members of the Mensa Czech Republic visiting the neuroinformatics lab at the University of West Bohemia. Each provided dataset contains a complete or partial set of data obtained from the following measurements: hands and legs reaction times, color vision, spirometry, electrocardiography, blood pressure, blood glucose, body proportions and flexibility. It also provides a sufficient set of metadata (age, gender and summary of the participant's current life style and health to allow researchers to perform further analysis. This article has two main aims. The first aim is to provide a well annotated collection of human reaction times and health related data that is suitable for further analysis of lifestyle and human cognitive and physical performance. This data collection is complemented with a preliminarily statistical evaluation. The second aim is to present a procedure of efficient acquisition of human reaction times and supporting health related data in non-lab and lab conditions. Keywords: Reaction time, Health related data, Cognitive and physical performance, Chronic disease, Data acquisition, Data collection, Software for data collection

The browning value changes and spectral analysis on the Maillard reaction product from glucose and methionine model system

Science.gov (United States)

Al-Baarri, A. N.; Legowo, A. M.; Widayat

2018-01-01

D-glucose has been understood to provide the various effect on the reactivity in Maillard reaction resulting in the changes in physical performance of food product. Therefore this research was done to analyse physical appearance of Maillard reaction product made of D-glucose and methionine as a model system. The changes in browning value and spectral analysis model system were determined. The glucose-methionine model system was produced through the heating treatment at 50°C and RH 70% for 24 hours. The data were collected for every three hour using spectrophotometer. As result, browning value was elevated with the increase of heating time and remarkably high if compare to the D-glucose only. Furthermore, the spectral analysis showed that methionine turned the pattern of peak appearance. As conclusion, methionine raised the browning value and changed the pattern of spectral analysis in Maillard reaction model system.

Comparing transfusion reaction rates for various plasma types: a systematic review and meta-analysis/regression.

Science.gov (United States)

Saadah, Nicholas H; van Hout, Fabienne M A; Schipperus, Martin R; le Cessie, Saskia; Middelburg, Rutger A; Wiersum-Osselton, Johanna C; van der Bom, Johanna G

2017-09-01

We estimated rates for common plasma-associated transfusion reactions and compared reported rates for various plasma types. We performed a systematic review and meta-analysis of peer-reviewed articles that reported plasma transfusion reaction rates. Random-effects pooled rates were calculated and compared between plasma types. Meta-regression was used to compare various plasma types with regard to their reported plasma transfusion reaction rates. Forty-eight studies reported transfusion reaction rates for fresh-frozen plasma (FFP; mixed-sex and male-only), amotosalen INTERCEPT FFP, methylene blue-treated FFP, and solvent/detergent-treated pooled plasma. Random-effects pooled average rates for FFP were: allergic reactions, 92/10 5 units transfused (95% confidence interval [CI], 46-184/10 5 units transfused); febrile nonhemolytic transfusion reactions (FNHTRs), 12/10 5 units transfused (95% CI, 7-22/10 5 units transfused); transfusion-associated circulatory overload (TACO), 6/10 5 units transfused (95% CI, 1-30/10 5 units transfused); transfusion-related acute lung injury (TRALI), 1.8/10 5 units transfused (95% CI, 1.2-2.7/10 5 units transfused); and anaphylactic reactions, 0.8/10 5 units transfused (95% CI, 0-45.7/10 5 units transfused). Risk differences between plasma types were not significant for allergic reactions, TACO, or anaphylactic reactions. Methylene blue-treated FFP led to fewer FNHTRs than FFP (risk difference = -15.3 FNHTRs/10 5 units transfused; 95% CI, -24.7 to -7.1 reactions/10 5 units transfused); and male-only FFP led to fewer cases of TRALI than mixed-sex FFP (risk difference = -0.74 TRALI/10 5 units transfused; 95% CI, -2.42 to -0.42 injuries/10 5 units transfused). Meta-regression demonstrates that the rate of FNHTRs is lower for methylene blue-treated compared with FFP, and the rate of TRALI is lower for male-only than for mixed-sex FFP; whereas no significant differences are observed between plasma types for allergic reactions, TACO

Effects of alpha-amylase reaction mechanisms on analysis of resistant-starch contents.

Science.gov (United States)

Moore, Samuel A; Ai, Yongfeng; Chang, Fengdan; Jane, Jay-lin

2015-01-22

This study aimed to understand differences in the resistant starch (RS) contents of native and modified starches obtained using two standard methods of RS content analysis: AOAC Method 991.43 and 2002.02. The largest differences were observed in native potato starch, cross-linked wheat distarch phosphate, and high-amylose corn starch stearic-acid complex (RS5) between using AOAC Method 991.43 with Bacillus licheniformis α-amylase (BL) and AOAC Method 2002.02 with porcine pancreatic α-amylase (PPA). To determine possible reasons for these differences, we hydrolyzed raw-starch granules with BL and PPA with equal activity at pH 6.9 and 37°C for up to 84 h and observed the starch granules displayed distinct morphological differences after the hydrolysis. Starches hydrolyzed by BL showed erosion on the surface of the granules; those hydrolyzed by PPA showed pitting on granule surfaces. These results suggested that enzyme reaction mechanisms, including the sizes of the binding sites and the reaction patterns of the two enzymes, contributed to the differences in the RS contents obtained using different methods of RS analysis. Copyright © 2014 Elsevier Ltd. All rights reserved.

Synthesis by the Pechini method and reaction combustion for the preparation of TiO2: a comparative analysis

International Nuclear Information System (INIS)

Almeida, E.P.; Ribeiro, P.C.; Freitas, N.L.; Lira, H.L.; Costa, A.C.F.M. da; Kiminami, R.H.G.A.

2009-01-01

The aim of this work is to prepare TiO 2 powder by Pechini and combustion reaction methods. A comparative analysis between the structural and morphological results obtained by the two methods was investigated. The powders were characterized by X-ray diffractions (XRD), infrared analysis, nitrogen adsorption (BET) and particle size distribution. The results from XRD show that the powders prepared by Pechini method and by combustion reaction using aniline as fuel, present anatase as major phase and traces of rutile phase. The values of crystallite size and surface area from BET were: 30 e 44 nm; 6.2 e 4.4 m 2 /g, for the powders prepared by Pechini and combustion reaction, respectively. The values of particle size were: 21.9 e 5.3 μm, for the powders prepared by Pechini and combustion reaction, respectively. The Pechini method was more suitable to obtain powders with irregular agglomerates, in the block shape with particles bonded softly and small crystallite size. (author)

Reaction kinetics of polybutylene terephthalate polycondensation reaction

NARCIS (Netherlands)

Darda, P. J.; Hogendoorn, J. A.; Versteeg, G. F.; Souren, F.

2005-01-01

The kinetics of the forward polycondensation reaction of polybutylene terephthalate (PBT) has been investigated using thermogravimetric analysis (TGA). PBT - prepolymer with an initial degree of polymerization of 5.5 was used as starting material. The PBT prepolymer was prepared from dimethyl

Component Analysis of Sweet BV and Clinical Trial on Antibody Titer and Allergic Reactions

Directory of Open Access Journals (Sweden)

Ki Rok, Kwon

2006-06-01

Full Text Available Objectives : The aim of this study was to observe prevention of allergic reactions of Sweet Bee Venom (removing enzyme components from Bee Venom. Methods : Content analysis of Sweet Bee Venom and Bee Venom was rendered using HPLC method and characterization of Anti-Sweet Bee Venom in Rabbit Serum. Clinical observation was conducted for inducement of allergic responses to Sweet BV. Results : 1. Analyzing melittin content using HPLC, Sweet BV contained 34.9% more melittin than Bee venom pharmacopuncture at same concentration. 2. Observing chromatogram of HPLC, removal of the enzyme was successfully rendered on Sweet BV. 3. The anti-serum of Sweet BV showed high titers against melittin and bee venom and relatively low titer against phospholipase A2. 4. After conducting approximately 3,000 cases of Sweet BV administration, not a single case of generalized anaphylatic reaction occurred in clinical observation. 5. Mild compared to the bee venom pharmacopuncture, Sweet BV showed some acute hypersensitive reactions of edema, itchiness, and aching locally. 6. Sweet BV was administered on six patients with previous history of suffering from generalized acute hypersensitive reactions with the bee venom. None of the patients showed allergic reactions with Sweet BV, suggesting it can effectively prevent anaphylatic shock which may occur after the bee venom pharmacopuncture procedure. Conclusion : Summarizing above results, Sweet Bee Venom appears to be an effective measurement against allergic reactions from the bee venom pharmacopuncture especially against anaphylatic shock.

Three-dimensional TDHF calculation for reactions of unstable nuclei

Energy Technology Data Exchange (ETDEWEB)

Kim, Ka-Hae; Otsuka, Takaharu [Tokyo Univ. (Japan). Dept. of Physics; Bonche, P.

1998-07-01

The fusion is studied for reactions between a stable and an unstable nuclei with neutron skin. The reactions {sup 16,28}O+{sup 40}Ca and {sup 16}O+{sup 16,28}O are taken as examples, and the three-dimensional time-dependent Hartree-Fock method with the full Skyrme interaction is used. It is confirmed that the fusion cross section in low-energy region is sensitive to the interaction used in the calculation. (author)

Biomass pyrolysis and combustion integral and differential reaction heats with temperatures using thermogravimetric analysis/differential scanning calorimetry.

Science.gov (United States)

Shen, Jiacheng; Igathinathane, C; Yu, Manlu; Pothula, Anand Kumar

2015-06-01

Integral reaction heats of switchgrass, big bluestem, and corn stalks were determined using thermogravimetric analysis/differential scanning calorimetry (TGA/DSC). Iso-conversion differential reaction heats using TGA/DSC pyrolysis and combustion of biomass were not available, despite reports available on heats required and released. A concept of iso-conversion differential reaction heats was used to determine the differential reaction heats of each thermal characteristics segment of these materials. Results showed that the integral reaction heats were endothermic from 30 to 700°C for pyrolysis of switchgrass and big bluestem, but they were exothermic for corn stalks prior to 587°C. However, the integral reaction heats for combustion of the materials followed an endothermic to exothermic transition. The differential reaction heats of switchgrass pyrolysis were predominantly endothermic in the fraction of mass loss (0.0536-0.975), and were exothermic for corn stalks (0.0885-0.850) and big bluestem (0.736-0.919). Study results provided better insight into biomass thermal mechanism. Published by Elsevier Ltd.

[Confirming Indicators of Qualitative Results by Chromatography-mass Spectrometry in Biological Samples].

Science.gov (United States)

Liu, S D; Zhang, D M; Zhang, W; Zhang, W F

2017-04-01

Because of the exist of complex matrix, the confirming indicators of qualitative results for toxic substances in biological samples by chromatography-mass spectrometry are different from that in non-biological samples. Even in biological samples, the confirming indicators are different in various application areas. This paper reviews the similarities and differences of confirming indicators for the analyte in biological samples by chromatography-mass spectrometry in the field of forensic toxicological analysis and other application areas. These confirming indicators include retention time （RT）, relative retention time （RRT）, signal to noise （S/N）, characteristic ions, relative abundance of characteristic ions, parent ion-daughter ion pair and abundance ratio of ion pair, etc. Copyright© by the Editorial Department of Journal of Forensic Medicine.

High-throughput DNA methylation analysis in anorexia nervosa confirms TNXB hypermethylation.

Science.gov (United States)

Kesselmeier, Miriam; Pütter, Carolin; Volckmar, Anna-Lena; Baurecht, Hansjörg; Grallert, Harald; Illig, Thomas; Ismail, Khadeeja; Ollikainen, Miina; Silén, Yasmina; Keski-Rahkonen, Anna; Bulik, Cynthia M; Collier, David A; Zeggini, Eleftheria; Hebebrand, Johannes; Scherag, André; Hinney, Anke

2018-04-01

Patients with anorexia nervosa (AN) are ideally suited to identify differentially methylated genes in response to starvation. We examined high-throughput DNA methylation derived from whole blood of 47 females with AN, 47 lean females without AN and 100 population-based females to compare AN with both controls. To account for different cell type compositions, we applied two reference-free methods (FastLMM-EWASher, RefFreeEWAS) and searched for consensus CpG sites identified by both methods. We used a validation sample of five monozygotic AN-discordant twin pairs. Fifty-one consensus sites were identified in AN vs. lean and 81 in AN vs. population-based comparisons. These sites have not been reported in AN methylation analyses, but for the latter comparison 54/81 sites showed directionally consistent differential methylation effects in the AN-discordant twins. For a single nucleotide polymorphism rs923768 in CSGALNACT1 a nearby site was nominally associated with AN. At the gene level, we confirmed hypermethylated sites at TNXB. We found support for a locus at NR1H3 in the AN vs. lean control comparison, but the methylation direction was opposite to the one previously reported. We confirm genes like TNXB previously described to comprise differentially methylated sites, and highlight further sites that might be specifically involved in AN starvation processes.

Analyses for experiment on sodium-water reaction temperature by the CHAMPAGNE code

International Nuclear Information System (INIS)

Yoshioka, Naoki; Kishida, Masako; Yamada, Yumi

2000-03-01

In this work, analyses on sodium-water reaction temperature in the new SWAT-1(SWAT-1R) test were completed by the CHAMPAGNE code in order to understand void and velocity distribution in sodium system, which was difficult to be measured in experiments. The application method of the RELAP5/Mod2 code was investigated to LMFBR steam generator (SG) blow down analysis, too. The following results were obtained. (1) Analyses on sodium-water reaction temperature in the SWAT-1R test. 1) Analyses were carried out for the SWAT-1R test under the condition water leak rate 600 g/s by treating the pressure loss coefficient, the interface friction coefficient and the coefficient related to reaction rate as parameters. The effect and mechanism of each parameter on the shape of reaction zone were well understood by these analyses. 2) The void and velocity distribution in sodium system were estimated by use of the most suitable parameters. These analytical results are expected to be useful for planning of the SWAT-1R test and evaluation of test result. (2) Investigation of the RELAP5/Mod2 code. 1) The items to be improved in the RELAP5/Mod2 code were clarified to apply this code to the FBR SG blow down analysis. 2) One of these items was an addition of the shell-side (sodium-side) model. A sodium-side model was designed and added to the RELAP5/Mod2 code. Test calculations were carried out by this improved code and the basic function of this code was confirmed. (author)

Automated Prediction of Catalytic Mechanism and Rate Law Using Graph-Based Reaction Path Sampling.

Science.gov (United States)

Habershon, Scott

2016-04-12

In a recent article [ J. Chem. Phys. 2015 , 143 , 094106 ], we introduced a novel graph-based sampling scheme which can be used to generate chemical reaction paths in many-atom systems in an efficient and highly automated manner. The main goal of this work is to demonstrate how this approach, when combined with direct kinetic modeling, can be used to determine the mechanism and phenomenological rate law of a complex catalytic cycle, namely cobalt-catalyzed hydroformylation of ethene. Our graph-based sampling scheme generates 31 unique chemical products and 32 unique chemical reaction pathways; these sampled structures and reaction paths enable automated construction of a kinetic network model of the catalytic system when combined with density functional theory (DFT) calculations of free energies and resultant transition-state theory rate constants. Direct simulations of this kinetic network across a range of initial reactant concentrations enables determination of both the reaction mechanism and the associated rate law in an automated fashion, without the need for either presupposing a mechanism or making steady-state approximations in kinetic analysis. Most importantly, we find that the reaction mechanism which emerges from these simulations is exactly that originally proposed by Heck and Breslow; furthermore, the simulated rate law is also consistent with previous experimental and computational studies, exhibiting a complex dependence on carbon monoxide pressure. While the inherent errors of using DFT simulations to model chemical reactivity limit the quantitative accuracy of our calculated rates, this work confirms that our automated simulation strategy enables direct analysis of catalytic mechanisms from first principles.

Ureaplasma parvum and Mycoplasma genitalium are found to be significantly associated with microscopy-confirmed urethritis in a routine genitourinary medicine setting.

Science.gov (United States)

Cox, Ciara; McKenna, James P; Watt, Alison P; Coyle, Peter V

2016-09-01

Inflammation of the urethra defined by an excess of polymorphonuclear leukocytes in the absence of sexually transmitted Chlamydia trachomatis and Neisseria gonorrhoeae is called non-chlamydial non-gonococcal urethritis (NCNGU). Although Mycoplasma genitalium is now recognised as causing a sexually transmitted infection, the clinical significance of the other Mollicute species is less clear. This study used specific real-time quantitative polymerase chain reaction assays to detect and quantify four Mollicute species, M. genitalium, M. hominis, Ureaplasma urealyticum and U. parvum, in urine specimens from men with and without NCNGU. A total of 165 urine specimens from male patients attending a genitourinary medicine clinic were eligible for the study, with microscopy-confirmed (≥5 polymorphonuclear leukocytes in urethral swab) NCNGU in 75 (45.5%) and non-confirmed NCNGU in 90 (54.5%). Chi-squared statistical analysis indicated a significantly higher prevalence of U. parvum (17.3% vs. 5.6%; p = 0.03) and M. genitalium (12% vs. 0%; p < 0.001) in NCNGU. In a subset analysis, M. genitalium was also significantly (p = 0.03) higher in men who have sex with men (MSM; 13.5%) compared to non-MSM (3.1%). No significant associations were reported for U. urealyticum and M. hominis In conclusion, this study supports a clinically significant role in NGNCU for both U. parvum and M. genitalium. © The Author(s) 2015.

Plutonian Moon confirmed

Science.gov (United States)

In late February, two separate observations confirmed the 1978 discovery by U.S. Naval Observatory scientist James W. Christy of a moon orbiting the planet Pluto. According to the U.S. Naval Observatory, these two observations were needed before the International Astronomical Society (IAS) would officially recognize the discovery.Two types of observations of the moon, which was named Charon after the ferryman in Greek mythology who carried the dead to Pluto's realm, were needed for confirmation: a transit, in which the moon passes in front of Pluto, and an occultation, in which the moon passes behind the planet. These two phenomena occur only during an 8-year period every 124 years that had been calculated to take place during 1984-1985. Both events were observed in late February.

Two reactions method for accurate analysis by irradiation with charged particles

International Nuclear Information System (INIS)

Ishii, K.; Sastri, C.S.; Valladon, M.; Borderie, B.; Debrun, J.L.

1978-01-01

In the average stopping power method the formula error itself was negligible but systematic errors could be introduced by the stopping power data used in this formula. A method directly derived from the average stopping power method, but based on the use of two nuclear reactions, is described here. This method has a negligible formula error and does not require the use of any stopping power or range data: accurate and 'self-consistent' analysis by irradiation with charged particles is then possible. (Auth.)

Global sensitivity analysis in stochastic simulators of uncertain reaction networks.

Science.gov (United States)

Navarro Jimenez, M; Le Maître, O P; Knio, O M

2016-12-28

Stochastic models of chemical systems are often subjected to uncertainties in kinetic parameters in addition to the inherent random nature of their dynamics. Uncertainty quantification in such systems is generally achieved by means of sensitivity analyses in which one characterizes the variability with the uncertain kinetic parameters of the first statistical moments of model predictions. In this work, we propose an original global sensitivity analysis method where the parametric and inherent variability sources are both treated through Sobol's decomposition of the variance into contributions from arbitrary subset of uncertain parameters and stochastic reaction channels. The conceptual development only assumes that the inherent and parametric sources are independent, and considers the Poisson processes in the random-time-change representation of the state dynamics as the fundamental objects governing the inherent stochasticity. A sampling algorithm is proposed to perform the global sensitivity analysis, and to estimate the partial variances and sensitivity indices characterizing the importance of the various sources of variability and their interactions. The birth-death and Schlögl models are used to illustrate both the implementation of the algorithm and the richness of the proposed analysis method. The output of the proposed sensitivity analysis is also contrasted with a local derivative-based sensitivity analysis method classically used for this type of systems.

Global sensitivity analysis in stochastic simulators of uncertain reaction networks

KAUST Repository

Navarro, María

2016-12-26

Stochastic models of chemical systems are often subjected to uncertainties in kinetic parameters in addition to the inherent random nature of their dynamics. Uncertainty quantification in such systems is generally achieved by means of sensitivity analyses in which one characterizes the variability with the uncertain kinetic parameters of the first statistical moments of model predictions. In this work, we propose an original global sensitivity analysis method where the parametric and inherent variability sources are both treated through Sobol’s decomposition of the variance into contributions from arbitrary subset of uncertain parameters and stochastic reaction channels. The conceptual development only assumes that the inherent and parametric sources are independent, and considers the Poisson processes in the random-time-change representation of the state dynamics as the fundamental objects governing the inherent stochasticity. A sampling algorithm is proposed to perform the global sensitivity analysis, and to estimate the partial variances and sensitivity indices characterizing the importance of the various sources of variability and their interactions. The birth-death and Schlögl models are used to illustrate both the implementation of the algorithm and the richness of the proposed analysis method. The output of the proposed sensitivity analysis is also contrasted with a local derivative-based sensitivity analysis method classically used for this type of systems.

Kinetic study of the annealing reactions in Cu-Ni-Fe alloys

International Nuclear Information System (INIS)

Donoso, E.

2014-01-01

The thermal aging of a Cu-45Ni-4Fe, Cu-34Ni-11Fe and Cu-33Ni-22Fe alloys tempered from 1173 K have been studied from Differential Scanning Calorimetry (DSC) and microhardness measurements. The analysis of DSC curves, from room temperature to 950 K, shows the presence of one exothermic reaction associated to the formation of FeNi 3 phase nucleating from a modulate structure, and one endothermic peak attributed to dissolution of this phase. Kinetic parameters were obtained using the usual Avrami-Erofeev equation, modified Kissinger method and integrated kinetic functions. Microhardness measurements confirmed the formation and dissolution of the FeNi 3 phase. (Author)

Modular verification of chemical reaction network encodings via serializability analysis

Science.gov (United States)

Lakin, Matthew R.; Stefanovic, Darko; Phillips, Andrew

2015-01-01

Chemical reaction networks are a powerful means of specifying the intended behaviour of synthetic biochemical systems. A high-level formal specification, expressed as a chemical reaction network, may be compiled into a lower-level encoding, which can be directly implemented in wet chemistry and may itself be expressed as a chemical reaction network. Here we present conditions under which a lower-level encoding correctly emulates the sequential dynamics of a high-level chemical reaction network. We require that encodings are transactional, such that their execution is divided by a “commit reaction” that irreversibly separates the reactant-consuming phase of the encoding from the product-generating phase. We also impose restrictions on the sharing of species between reaction encodings, based on a notion of “extra tolerance”, which defines species that may be shared between encodings without enabling unwanted reactions. Our notion of correctness is serializability of interleaved reaction encodings, and if all reaction encodings satisfy our correctness properties then we can infer that the global dynamics of the system are correct. This allows us to infer correctness of any system constructed using verified encodings. As an example, we show how this approach may be used to verify two- and four-domain DNA strand displacement encodings of chemical reaction networks, and we generalize our result to the limit where the populations of helper species are unlimited. PMID:27325906

The kinetics of substitution reaction of oxydiacetate and ...

Indian Academy of Sciences (India)

molar ratio 1:1 and the ternary complex Cu(R)B were recorded to confirm that ... tion, the values of the rate constants were determined. Figure 2. .... Table 4. The free enthalpy of activation values for the substitution reaction of CuODA with bipy.

Study of some direct reactions at 00 in 18O+26Mg and 18O+12C systems

International Nuclear Information System (INIS)

Payet, J.

1984-01-01

Direct transfer reactions induced by a 18 O beam on 12 C and 26 Mg targets, have been studied at the MP tandem (Orsay) with an experimental set up giving the possibility to have angular distributions up to 0 0 . Transfer reactions to discrete levels were analysed in the D.W.B.A. framework. This analysis confirms the interest as a spectroscopic tool of this 0 0 measurements. The ( 18 O, 16 O) and ( 18 O, 20 Ne) reactions were observed up to 40 MeV excitation energy. A diffractionnal model, including the one step direct transfer hypothesis, gives a qualitative agreement with the angular distributions and the energy spectra. A parametrization of a specific small angles development of the transfer amplitudes does not give good results with physical values for the parameters. 32 refs [fr

The Mechanical and Reaction Behavior of PTFE/Al/Fe2O3 under Impact and Quasi-Static Compression

Directory of Open Access Journals (Sweden)

Jun-yi Huang

2017-01-01

Full Text Available Quasi-static compression and drop-weight test were used to characterize the mechanical and reaction behavior of PTFE/Al/Fe2O3 composites. Two kinds of PTFE/Al/Fe2O3 composites were prepared with different mass of PTFE, and the reaction phenomenon and stress-strain curves were recorded; the residuals after reaction were analyzed by X-ray diffraction (XRD. The results showed that, under quasi-static compression condition, the strength of the materials is increased (from 37.1 Mpa to 77.2 Mpa with the increase of PTFE, and the reaction phenomenon occurred only in materials with high PTFE content. XRD analysis showed that the reaction between Al and Fe2O3 was not triggered with identical experimental conditions. In drop-weight tests, PTFE/Al/Fe2O3 specimens with low PTFE content were found to be more insensitive by high-speed photography, and a High Temperature Metal Slag Spray (HTMSS phenomenon was observed in both kinds of PTFE/Al/Fe2O3 composites, indicating the existence of thermite reaction, which was confirmed by XRD. In PTFE/Al/Fe2O3 system, the reaction between PTFE and Al precedes the reaction between Al and Fe2O3.

Theoretical analysis of consecutive reactions in adiabatic stirred tank reactors

International Nuclear Information System (INIS)

Jo, Byung Wook; Kim, Sun Il; Hong, Won Hae; Cha, Wol Suk; Kim, Soong Pyung; Kim, Jung Gyu

1990-01-01

By mathematical model for the case of the consecutive first-order exothermic reaction in an adiabatic CSTR, the effects of the system parameter i. e. relative residence time, heat of reaction and thermal sensitivity of reaction rate constant, on the concentration profile of the intermediate product of a consecutive reaction were obtained as follows. For fixed values of the ratio of the reaction rate constants t 1 / t 2 , the ratio of the correponding system parameter α where α>1 and the sensitivities of the reaction rate constants S1 and S2, the maximum value of the intermediate production dimensionless concentration increases with increase in the values of the relative energy parameter E1 and E2 and it decreases with a decrease in E1 and E2. For fixed values of the ratio of the reaction rate constants t 1 / t 2 , the ratio of the corresponding system parameter α where α 1 and t 2 and it increases with a decrease in S1 and S2. For fixed values of the ratio of the reaction rate constants t 1 / t 2 , the ratio of the corresponding system parameters α where α=1 and the relative energy parameters E1 and E2, the maximum value of the intermediate product dimensionless is constant with either increase or decrease in the sensitivities of the reaction rate constants S1 and S2. (Author)

Tuberculin skin testing: Spectrum of adverse reactions.

Science.gov (United States)

Praveen, Ramar; Bahuguna, Amit; Dhadwal, Bhumesh Singh

2015-01-01

Tuberculin skin testing (TST) is one of the primary diagnostic modalities recommended by the World Health Organization (WHO) and the National Institute for Health and Care Excellence (NICE) study conducted in the United Kingdom (UK) for diagnosing tuberculosis (TB). Even after acceptance as a diagnostic modality and stern standardization, TST has its own flaws that include a spectrum of adverse reactions. We report a series of cases with a spectrum of adverse reactions occurring with a higher frequency than present in the available evidence. The study has some demerits such as being a retrospective one with interobserver variation and lack of histopathological confirmation. The observation is presented to accentuate the fact that adverse reactions are not a rarity and that further studies are required to establish the cause and exact incidence of the same.

Experimental and numerical analysis of the combustor for a cogeneration system based on the aluminum/water reaction

International Nuclear Information System (INIS)

Milani, Massimo; Montorsi, Luca; Paltrinieri, Fabrizio; Stefani, Matteo

2014-01-01

Highlights: • Aluminum reaction with water is studied as a technology for hydrogen production. • A test rig is developed for the analysis of aluminum/water reaction. • The system is the core component of a cogeneration plant for hydrogen/power production. • The interaction of liquid aluminum jet and water steam stream is investigated. • The main capabilities of the injection system are assessed. - Abstract: The paper focuses on the design of the experimental apparatus aimed at analyzing the performance of the combustion chamber of a cogeneration system based on the reaction of liquid aluminum and water steam. The cogeneration system exploits the heat released by the oxidation of aluminum with water for super-heating the vapor of a steam cycle and simultaneously producing hydrogen. The only by-product is alumina, which in a closed loop can be recycled back and transformed again into aluminum. Therefore, aluminum is used as an energy carrier to transport the energy from the alumina reduction plant to the location of the proposed system. The water is also used in a closed loop since the amount of water produced employing the hydrogen obtained by the proposed system corresponds to the oxidizing water for the Al/H 2 O reaction. This study investigates the combustor where the liquid aluminum–steam reaction takes place. In particular, the design of the combustion chamber and the interaction between the liquid aluminum jet and the water steam flow are evaluated using a numerical and an experimental approach. The test rig is specifically designed for the analysis of the liquid aluminum injection in a slightly super-heated steam stream. The first experiments are carried out to verify the correct behavior of the test rig. Thermography is employed to qualitatively assess the steam entrainment of the liquid aluminum jet. Finally, the experimental measurements are compared with the multi-dimension multi-phase flow simulations in order to estimate the influence of

Chemical reaction of hexagonal boron nitride and graphite nanoclusters in mechanical milling systems

Energy Technology Data Exchange (ETDEWEB)

Muramatsu, Y.; Grush, M.; Callcott, T.A. [Univ. of Tennessee, Knoxville, TN (United States)] [and others

1997-04-01

Synthesis of boron-carbon-nitride (BCN) hybrid alloys has been attempted extensively by many researchers because the BCN alloys are considered an extremely hard material called {open_quotes}super diamond,{close_quotes} and the industrial application for wear-resistant materials is promising. A mechanical alloying (MA) method of hexagonal boron nitride (h-BN) with graphite has recently been studied to explore the industrial synthesis of the BCN alloys. To develop the MA method for the BCN alloy synthesis, it is necessary to confirm the chemical reaction processes in the mechanical milling systems and to identify the reaction products. Therefore, the authors have attempted to confirm the chemical reaction process of the h-BN and graphite in mechanical milling systems using x-ray absorption near edge structure (XANES) methods.

Chemical reaction of hexagonal boron nitride and graphite nanoclusters in mechanical milling systems

International Nuclear Information System (INIS)

Muramatsu, Y.; Grush, M.; Callcott, T.A.

1997-01-01

Synthesis of boron-carbon-nitride (BCN) hybrid alloys has been attempted extensively by many researchers because the BCN alloys are considered an extremely hard material called open-quotes super diamond,close quotes and the industrial application for wear-resistant materials is promising. A mechanical alloying (MA) method of hexagonal boron nitride (h-BN) with graphite has recently been studied to explore the industrial synthesis of the BCN alloys. To develop the MA method for the BCN alloy synthesis, it is necessary to confirm the chemical reaction processes in the mechanical milling systems and to identify the reaction products. Therefore, the authors have attempted to confirm the chemical reaction process of the h-BN and graphite in mechanical milling systems using x-ray absorption near edge structure (XANES) methods

Humidity independent mass spectrometry for gas phase chemical analysis via ambient proton transfer reaction.

Science.gov (United States)

Zhu, Hongying; Huang, Guangming

2015-03-31

In this work, a humidity independent mass spectrometric method was developed for rapid analysis of gas phase chemicals. This method is based upon ambient proton transfer reaction between gas phase chemicals and charged water droplets, in a reaction chamber with nearly saturate humidity under atmospheric pressure. The humidity independent nature enables direct and rapid analysis of raw gas phase samples, avoiding time- and sample-consuming sample pretreatments in conventional mass spectrometry methods to control sample humidity. Acetone, benzene, toluene, ethylbenzene and meta-xylene were used to evaluate the analytical performance of present method. The limits of detection for benzene, toluene, ethylbenzene and meta-xylene are in the range of ∼0.1 to ∼0.3 ppbV; that of benzene is well below the present European Union permissible exposure limit for benzene vapor (5 μg m(-3), ∼1.44 ppbV), with linear ranges of approximately two orders of magnitude. The majority of the homemade device contains a stainless steel tube as reaction chamber and an ultrasonic humidifier as the source of charged water droplets, which makes this cheap device easy to assemble and facile to operate. In addition, potential application of this method was illustrated by the real time identification of raw gas phase chemicals released from plants at different physiological stages. Copyright © 2015 Elsevier B.V. All rights reserved.

Development of fast reactor containment safety analysis code, CONTAIN-LMR. (3) Improvement of sodium-concrete reaction model

International Nuclear Information System (INIS)

Kawaguchi, Munemichi; Doi, Daisuke; Seino, Hiroshi; Miyahara, Shinya

2015-01-01

A computer code, CONTAIN-LMR, is an integrated analysis tool to predict the consequence of severe accident in a liquid metal fast reactor. Because a sodium-concrete reaction behavior is one of the most important phenomena in the accident, a Sodium-Limestone Concrete Ablation Model (SLAM) has been developed and installed into the original CONTAIN code at Sandia National Laboratories (SNL) in the U.S. The SLAM treats chemical reaction kinetics between the sodium and the concrete compositions mechanistically using a three-region model, containing a pool (sodium and reaction debris) region, a dry (boundary layer (B/L) and dehydrated concrete) region, and a wet (hydrated concrete) region, the application is limited to the reaction between sodium and limestone concrete. In order to apply SLAM to the reaction between sodium and siliceous concrete which is an ordinary structural concrete in Japan, the chemical reaction kinetics model has been improved to consider the new chemical reactions between sodium and silicon dioxide. The improved model was validated to analyze a series of sodium-concrete experiments which were conducted in Japan Atomic Energy Agency (JAEA). It has been found that relatively good agreement between calculation and experimental results is obtained and the CONTAIN-LMR code has been validated with regard to the sodium-concrete reaction phenomena. (author)

Study of 207Tl126 Produced in Deep-Inelastic Reactions

Directory of Open Access Journals (Sweden)

Wilson E.

2014-03-01

Full Text Available Deep-inelastic collisions of a 208Pb beam on a 208Pb target were performed using the ATLAS accelerator at Argonne National Laboratory. The Gammasphere detector array was used for the detection of prompt and delayed gamma-rays of the reaction products.207Tl is one proton away from the 208Pb doubly-magic nucleus. Its low-energy level structure is dominated by the single proton-hole states πs1/2−1, πd3/2−1 and πh11/2−1. The 11/2− state is isomeric with T1/2 = 1.33(11 s. The reaction partner of 207Tl is 209Bi, which has arelatively well established level scheme compared to 207Tl. Cross-coincidences between these two nuclei were used to confirm or establish levels above the 11/2− isomeric state in 207Tl. These states are obtained via breaking of the neutron core. Angular correlation analysis was performed on known transitions in 208Pb, proving the applicability of this method for multipolarity assignment.

Analysis of reaction schemes using maximum rates of constituent steps

Science.gov (United States)

Motagamwala, Ali Hussain; Dumesic, James A.

2016-01-01

We show that the steady-state kinetics of a chemical reaction can be analyzed analytically in terms of proposed reaction schemes composed of series of steps with stoichiometric numbers equal to unity by calculating the maximum rates of the constituent steps, rmax,i, assuming that all of the remaining steps are quasi-equilibrated. Analytical expressions can be derived in terms of rmax,i to calculate degrees of rate control for each step to determine the extent to which each step controls the rate of the overall stoichiometric reaction. The values of rmax,i can be used to predict the rate of the overall stoichiometric reaction, making it possible to estimate the observed reaction kinetics. This approach can be used for catalytic reactions to identify transition states and adsorbed species that are important in controlling catalyst performance, such that detailed calculations using electronic structure calculations (e.g., density functional theory) can be carried out for these species, whereas more approximate methods (e.g., scaling relations) are used for the remaining species. This approach to assess the feasibility of proposed reaction schemes is exact for reaction schemes where the stoichiometric coefficients of the constituent steps are equal to unity and the most abundant adsorbed species are in quasi-equilibrium with the gas phase and can be used in an approximate manner to probe the performance of more general reaction schemes, followed by more detailed analyses using full microkinetic models to determine the surface coverages by adsorbed species and the degrees of rate control of the elementary steps. PMID:27162366

Confirmation of the Dominant Defect Mechanism in Amorphous In-Zn-O Through the Application of In Situ Brouwer Analysis

Energy Technology Data Exchange (ETDEWEB)

Moffitt, Stephanie L. [Materials Science and Engineering Department, Northwestern University, Evanston Illinois 60208; Adler, Alexander U. [Materials Science and Engineering Department, Northwestern University, Evanston Illinois 60208; Gennett, Thomas [National Renewable Energy Laboratory, Golden Colorado 80401; Ginley, David S. [National Renewable Energy Laboratory, Golden Colorado 80401; Perkins, John D. [National Renewable Energy Laboratory, Golden Colorado 80401; Mason, Thomas O. [Materials Science and Engineering Department, Northwestern University, Evanston Illinois 60208; Zhou, X. -D.

2015-04-08

The dominant point defect mechanism of amorphous (a-) indium zinc oxide (IZO) was probed through in situ electrical characterization of sputtered a-IZO thin films in response to changes in oxygen partial pressure (pO2) at 300 degrees C. The results yielded a power law dependence of conductivity (s) versus pOinline image of ~-1/6. This experimental method, known as Brouwer analysis, confirms doubly-charged oxygen vacancies as the dominant defect species in a-IZO. The success of this study suggests that Brouwer analysis is a viable method for studying the defect mechanisms of amorphous oxides.

Measurement of pion polarizability and chiral anomaly in Primakoff reactions at COMPASS

Energy Technology Data Exchange (ETDEWEB)

Nagel, Thiemo; Friedrich, Jan Michael; Gerassimov, Sergei; Grabmueller, Stefanie; Haas, Florian; Ketzer, Bernhard; Konorov, Igor; Kuhn, Roland; Neubert, Sebastian; Paul, Stephan; Weitzel, Quirin [TU Muenchen, Physik-Department E18 (Germany); Dinkelbach, Anna-Maria [Prueftechnik Alignment Systems, Ismaning (Germany)

2008-07-01

In a pilot run in 2004, the COMPASS experiment at CERN observed the scattering of negative pions of 190 GeV/c off various nuclear targets, measuring soft processes. Primakoff reactions, i.e. interactions between the beam particle and a quasi-real photon from the Coulomb field of the nucleus, are used to study the physics of strong interaction at small momentum transfer. The inverse Compton scattering reaction {pi}{sup -}+Z{yields}{pi}{sup -}+{gamma}+Z gives access to the polarizabilities anti {alpha}{sub {pi}} and anti {beta}{sub {pi}} of the beam pion, which may be used to test chiral pertubation theory. Under the assumption of anti {alpha}{sub {pi}}+ anti {beta}{sub {pi}}=0 a preliminary result has been extracted which is in agreement with calculations of {chi}PT. The {pi}{sup 0} production reaction {pi}{sup -}+Z{yields}{pi}{sup -}+{pi}{sup 0}+Z permits determination of the F{sup 3{pi}} coupling constant of the {gamma}{yields}3{pi} vertex, a measurement crucial for the confirmation of the chiral anomaly hypothesis. Here, the current status of analysis will be shown.

Malonic acid concentration as a control parameter in the kinetic analysis of the Belousov-Zhabotinsky reaction under batch conditions.

Science.gov (United States)

Blagojević, Slavica M; Anić, Slobodan R; Cupić, Zeljko D; Pejić, Natasa D; Kolar-Anić, Ljiljana Z

2008-11-28

The influence of the initial malonic acid concentration [MA]0 (8.00 x 10(-3) sulfuric acid (1.00 mol dm(-3)) and cerium sulfate (2.50 x 10(-3) mol dm(-3)) on the dynamics and the kinetics of the Belousov-Zhabotinsky (BZ) reactions was examined under batch conditions at 30.0 degrees C. The kinetics of the BZ reaction was analyzed by the earlier proposed method convenient for the examinations of the oscillatory reactions. In the defined region of parameters where oscillograms with only large-amplitude relaxation oscillations appeared, the pseudo-first order of the overall malonic acid decomposition with a corresponding rate constant of 2.14 x 10(-2) min(-1) was established. The numerical results on the dynamics and kinetics of the BZ reaction, carried out by the known skeleton model including the Br2O species, were in good agreement with the experimental ones. The already found saddle node infinite period (SNIPER) bifurcation point in transition from a stable quasi-steady state to periodic orbits and vice versa is confirmed by both experimental and numerical investigations of the system under consideration. Namely, the large-amplitude relaxation oscillations with increasing periods between oscillations in approaching the bifurcation points at the beginning and the end of the oscillatory domain, together with excitability of the stable quasi-steady states in their vicinity are obtained.

Collaborative ring trial of the papaya endogenous reference gene and its polymerase chain reaction assays for genetically modified organism analysis.

Science.gov (United States)

Wei, Jiaojun; Li, Feiwu; Guo, Jinchao; Li, Xiang; Xu, Junfeng; Wu, Gang; Zhang, Dabing; Yang, Litao

2013-11-27

The papaya (Carica papaya L.) Chymopapain (CHY) gene has been reported as a suitable endogenous reference gene for genetically modified (GM) papaya detection in previous studies. Herein, we further validated the use of the CHY gene and its qualitative and quantitative polymerase chain reaction (PCR) assays through an interlaboratory collaborative ring trial. A total of 12 laboratories working on detection of genetically modified organisms participated in the ring trial and returned test results. Statistical analysis of the returned results confirmed the species specificity, low heterogeneity, and single-copy number of the CHY gene among different papaya varieties. The limit of detection of the CHY qualitative PCR assay was 0.1%, while the limit of quantification of the quantitative PCR assay was ∼25 copies of haploid papaya genome with acceptable PCR efficiency and linearity. The differences between the tested and true values of papaya content in 10 blind samples ranged from 0.84 to 6.58%. These results indicated that the CHY gene was suitable as an endogenous reference gene for the identification and quantification of GM papaya.

Neutron transfer reactions in the fp-shell region

International Nuclear Information System (INIS)

Mahgoub, Mahmoud

2008-01-01

Neutron transfer reactions were used to study the stability of the magic number N=28 near 56 Ni. On one hand the one-neutron pickup (d,p) reaction was used for precision spectroscopy of single-particle levels in 55 Fe. On the other hand we investigated the two-neutron transfer mechanism into 56 Ni using the pickup reaction 58 Ni(vectorp,t) 56 Ni. In addition the reliability of inverse kinematics reactions at low energy to study exotic nuclei was tested by the neutron transfer reactions t( 40 Ar,p) 42 Ar and d( 54 Fe,p) 55 Fe using tritium and deuterium targets, respectively, and by comparing the results with those of the normal kinematics reactions. The experimental data, differential cross-section and analyzing powers, are compared to DWBA and coupled channel calculations utilizing the code CHUCK3. By performing the single-neutron stripping reaction (vectord,p) on 54 Fe the 1f 7/2 shell in the ground state configuration was found to be partly broken. The instability of the 1f 7/2 shell and the magic number N=28 was confirmed once by observing a number of levels with J π = 7/2 - at low excitation energies, which should not be populated if 54 Fe has a closed 1f 7/2 shell, and also by comparing our high precision experimental data with a large scale shell model calculation using the ANTOINE code [5]. Calculations including a partly broken 1f 7/2 shell show better agreement with the experiment. The instability of the 1f 7/2 shell was confirmed also by performing the two-neutron pick-up reaction (vectorp,t) on 58 Ni to study 56 Ni, where a considerable improvement in the DWBA calculation was observed after considering 1f 7/2 as a broken shell. To prove the reliability of inverse kinematics transfer reactions at low energies (∝ 2 AMeV), the aforementioned single-neutron transfer reaction (d,p) was repeated using a beam of 54 Fe ions and a deuteron target. From this inverse kinematics experiment we were able to reproduce the absolute cross-section and angular

CLASSIFICATION OF THE MGR PERFORMANCE CONFIRMATION DATA ACQUISITION/MONITORING SYSTEM

International Nuclear Information System (INIS)

J.A. Ziegler

1999-01-01

The purpose of this analysis is to document the Quality Assurance (QA) classification of the Monitored Geologic Repository (MGR) performance confirmation data acquisition/monitoring system structures, systems and components (SSCs) performed by the MGR Safety Assurance Department. This analysis also provides the basis for revision of YMP/90-55Q, Q-List (YMF 1998). The Q-List identifies those MGR SSCs subject to the requirements of DOE/RW-0333PY ''Quality Assurance Requirements and Description'' (QARD) (DOE 1998)

Uranium analysis in urine by inductively coupled plasma dynamic reaction cell mass spectrometry

Energy Technology Data Exchange (ETDEWEB)

Ejnik, John W. [Northern Michigan University, Chemistry Department, Marquette, MI (United States); Todorov, Todor I.; Mullick, Florabel G.; Centeno, Jose A. [Armed Forces Institute of Pathology (AFIP), Division of Biophysical Toxicology, Washington, DC (United States); Squibb, Katherine; McDiarmid, Melissa A. [University of Maryland, School of Medicine, Baltimore, MD (United States)

2005-05-01

Urine uranium concentrations are the best biological indicator for identifying exposure to depleted uranium (DU). Internal exposure to DU causes an increased amount of urine uranium and a decreased ratio of {sup 235}U/{sup 238}U in urine samples, resulting in measurements that vary between 0.00725 and 0.002 (i.e., natural and depleted uranium's {sup 235}U/{sup 238}U ratios, respectively). A method based on inductively coupled plasma dynamic reaction cell mass spectrometry (ICP-DRC-MS) was utilized to identify DU in urine by measuring the quantity of total U and the {sup 235}U/{sup 238}U ratio. The quantitative analysis was achieved using {sup 233}U as an internal standard. The analysis was performed both with and without the reaction gas oxygen. The reaction gas converted ionized {sup 235}U{sup +} and {sup 238}U{sup +} into {sup 235}UO{sub 2}{sup +} (m/z=267) and {sup 238}UO{sub 2}{sup +} (m/z=270). This conversion was determined to be over 90% efficient. A polyatomic interference at m/z 234.8 was successfully removed from the {sup 235}U signal under either DRC operating conditions (with or without oxygen as a reaction gas). The method was validated with 15 urine samples of known uranium compositions. The method detection limit for quantification was determined to be 0.1 pg U mL{sup -1} urine and an average coefficient of variation (CV) of 1-2% within the sample measurements. The method detection limit for determining {sup 235}U/{sup 238}U ratio was 3.0 pg U mL{sup -1} urine. An additional 21 patient samples were analyzed with no information about medical history. The measured {sup 235}U/{sup 238}U ratio within the urine samples correctly identified the presence or absence of internal DU exposure in all 21 patients. (orig.)

Scaling analysis in modeling transport and reaction processes a systematic approach to model building and the art of approximation

CERN Document Server

Krantz, William B

2007-01-01

This book is unique as the first effort to expound on the subject of systematic scaling analysis. Not written for a specific discipline, the book targets any reader interested in transport phenomena and reaction processes. The book is logically divided into chapters on the use of systematic scaling analysis in fluid dynamics, heat transfer, mass transfer, and reaction processes. An integrating chapter is included that considers more complex problems involving combined transport phenomena. Each chapter includes several problems that are explained in considerable detail. These are followed by several worked examples for which the general outline for the scaling is given. Each chapter also includes many practice problems. This book is based on recognizing the value of systematic scaling analysis as a pedagogical method for teaching transport and reaction processes and as a research tool for developing and solving models and in designing experiments. Thus, the book can serve as both a textbook and a reference boo...

Benchmark calculations of thermal reaction rates. I - Quantal scattering theory

Science.gov (United States)

Chatfield, David C.; Truhlar, Donald G.; Schwenke, David W.

1991-01-01

The thermal rate coefficient for the prototype reaction H + H2 yields H2 + H with zero total angular momentum is calculated by summing, averaging, and numerically integrating state-to-state reaction probabilities calculated by time-independent quantum-mechanical scattering theory. The results are very carefully converged with respect to all numerical parameters in order to provide high-precision benchmark results for confirming the accuracy of new methods and testing their efficiency.

A detailed study of the amorphisation reaction in NiMo alloys by diffraction and scattering methods

International Nuclear Information System (INIS)

Rose, P.

1995-01-01

X-ray and neutron diffraction and neutron small angle scattering (SAS) measurements have been made on NiMo specimens prepared by mechanical alloying (MA). We have extended our earlier studies and measured a new series of MA treated NiMo samples. Molybdenum scatters X-rays more strongly than nickel, but with neutrons, the reverse is the case. Analysis of the X-ray and neutron diffraction patterns together, therefore provides an accurate measurement of the consumption of both constituents in the reaction. The diffraction data on the new samples confirm that the consumption of the parent crystalline materials follows an exponential dependence with the time of MA treatment and also provides evidence of a ''delayed start'' to the reaction. This is consistent with an initial period of mixing of the constituents before the onset of (atomic) interdiffusion and amorphisation. The neutron SAS experiments have been made on Ni 47.7 Mo 52.3 MA treated specimens, which can be ''contrast-matched'' to reduce the scattering from the external surfaces of the powder grains. The new neutron SAS data confirm the presence of fractal surfaces between the alloy constituents, for samples in the early stages of the MA process. (orig.)

A study of the accelerated zircaloy-4 oxidation reaction with H2O/H2 mixture gas

International Nuclear Information System (INIS)

Kim, Y. S.; Cho, I. J.

2001-01-01

A study of the Zircaloy-4 reaction with H 2 O/H 2 mixture gas is carried out by using TGA (Thermo Gravimetric Apparatus) to estimate the hydrogen embrittlement which can possibly cause catastrophic nuclear fuel rod failure. Reaction rates are measured as a function of H 2 /H 2 O. In the experiments reaction temperature is set at 500 .deg. C and total pressure of the mixture gas is maintained at 1 atm. Experimental results reveal that hydriding and oxidation reaction are competing. In early stage, hydriding kinetics is faster than oxidation, however, oxidant in H 2 O forms oxide on the surface as steam environment is maintained, thus, this growing oxide begins to protect the zirconium base metal against hydrogen permeation. In this second stage, the total kinetic rate follows enhanced oxidation kinetics. In the final stage, it is observed that the oxide is broken down and massive hydriding takes place through the mechanical defects in the oxide, whose kinetics is similar to pure hydriding kinetics. These results are confirmed by SEM and EDX analysis along with hydrogen concentration measurements

Calcium hydroxide silylation reaction with trimethylchlorosilane

Directory of Open Access Journals (Sweden)

Novoselnov Anatoliy A.

2016-01-01

Full Text Available The silylation reaction of a calcium hydroxide with a trimethylchlorosilane is studied as a silylation model by the gas-liquid chromatography. The silylation process is divided into three stages. A material balance of these stages is calculated. The schemes of the reactions at each stage of the process are proposed. The modified calcium hydroxide obtained at three repetitive stages of the silylation reaction has been investigated by the x-ray phase analysis, IR spectroscopy, thermal analysis, electron microscopy in a combination with the elemental analysis. It has been determined that at the first stage of the interaction the processes of the trimethylchlorosilane hydrolysis and of the hydrolysis products condensation dominate, and at the same time an adsorption process of the trimethylchlorosilane and its derivatives starts. Further, the hydrolysis of the trimethylchlorosilane by the «new» portions of a water formed in the reaction of a calcium hydroxide with a hydrogen chloride takes place, simultaneously the secondary reactions of the Si-O-Ca – ties’ formation and cleavage occur including as a silylation-desilylation dynamic equilibrium process.

Calibration and Confirmation in Geophysical Models

Science.gov (United States)

Werndl, Charlotte

2016-04-01

For policy decisions the best geophysical models are needed. To evaluate geophysical models, it is essential that the best available methods for confirmation are used. A hotly debated issue on confirmation in climate science (as well as in philosophy) is the requirement of use-novelty (i.e. that data can only confirm models if they have not already been used before. This talk investigates the issue of use-novelty and double-counting for geophysical models. We will see that the conclusions depend on the framework of confirmation and that it is not clear that use-novelty is a valid requirement and that double-counting is illegitimate.

Kinetics of the high temperature oxygen exchange reaction on 238PuO2 powder

International Nuclear Information System (INIS)

Whiting, Christofer E.; Du, Miting; Felker, L. Kevin; Wham, Robert M.; Barklay, Chadwick D.; Kramer, Daniel P.

2015-01-01

Oxygen exchange reactions performed on PuO 2 suggest the reaction is influenced by at least three mechanisms: an internal chemical reaction, surface mobility of active species/defects, and surface exchange of gaseous oxygen with lattice oxygen. Activation energies for the surface mobility and internal chemical reaction are presented. Determining which mechanism is dominant appears to be a complex function including at least specific surface area and temperature. Thermal exposure may also impact the oxygen exchange reaction by causing reductions in the specific surface area of PuO 2 . Previous CeO 2 surrogate studies exhibit similar behavior, confirming that CeO 2 is a good qualitative surrogate for PuO 2 , in regards to the oxygen exchange reaction. Comparison of results presented here with previous work on the PuO 2 oxygen exchange reaction allows complexities in the previous work to be explained. These explanations allowed new conclusions to be drawn, many of which confirm the conclusions presented here. - Highlights: • PuO 2 Oxygen exchange kinetics can be influenced by at least 3 different mechanisms. • An internal chemical reaction controls the rate at high temperature and large SSA. • Surface mobility and surface exchange influence rate at lower temperatures and SSA. • Exchange temperatures may alter SSA and make data difficult to interpret.

Investigation of Na-CO2 Reaction with Initial Reaction in Various Reacting Surface

International Nuclear Information System (INIS)

Kim, Hyun Su; Park, Gunyeop; Kim, Soo Jae; Park, Hyun Sun; Kim, Moo Hwan; Wi, Myung-Hwan

2015-01-01

The reaction products that cause oxidation and erosion are threaten the heat transfer tubes so that it is necessary to investigate Na-CO 2 reaction according to various experimental parameter. Unlike SWR, Na-CO 2 reaction is more complex to deal with reaction kinetics. Since a comprehensive understanding of Na-CO 2 reaction mechanism is crucial for the safety analysis, the reaction phenomenon under the various conditions was investigated. The current issue is to make a database for developing computational code for CO 2 gas leak situation because it is experimentally difficult to analyze the actual accident situation. Most studies on Na-CO 2 interaction reports that chemical reaction is getting vigorous as temperature increased and reactivity is sensitive as temperature change between 400 .deg. C and 600 .deg. C. Therefore, temperature range is determined based on the operating condition (450 - 500 .deg. C) of KALIMER-600 employed as supercritical CO 2 brayton cycle energy conversion system for Na-CO 2 heat exchanger. And next parameter is sodium surface area which contact between sodium and CO 2 when CO 2 is injected into sodium pool in the accident situation. So, the fundamental surface reaction is experimentally studied in the range of 8 - 12cm 2 . Additionally, it has been reported in recent years that CO 2 Flow rate affects reactivity less significantly and CO 2 flow rate is assumed that 5 SLPM (standard liter per minute) is suitable as a basis for a small leakage. The finally selected control parameters is sodium temperature and reacting surface area with constant CO 2 flow rate. Na-CO 2 reaction test is performed for investigating risk of potential accident which contacts with liquid sodium and CO 2 . Amount of reaction is saturated as time passed because of kept a balance between production of solid phase reaction products and amount of diffusivity. These results contribute to make a database for the SFR safety analysis and additional experiments are needed

Scattering and transfer reactions with heavy ions

International Nuclear Information System (INIS)

Hussein, M.S.

From the elastic scattering analysis the input parameters are found for the inelastic scattering analysis and the transfer reactions of the heavy ion reactions. The main theme reported is the likeness and conection among these processes. (L.C.) [pt

Measurement and analysis of $\\alpha$ particle induced reactions on yttrium

CERN Document Server

Singh, N L; Chintalapudi, S N

2000-01-01

Excitation functions for /sup 89/Y[( alpha ,3n); ( alpha ,4n); ( alpha , p3n); ( alpha , alpha n); ( alpha , alpha 2n)] reactions were measured up to 50 MeV using stacked foil activation technique and HPGe gamma ray spectroscopy method. The experimental data were compared with calculations considering equilibrium as well as preequilibrium reactions according to the hybrid model of Blann (ALICE/90). For ( alpha , xnyp) type of reactions, the precompound contributions are described by the model. There seems to be indications of direct inelastic scattering effects in ( alpha , alpha xn) type of reactions. To the best of our knowledge, the excitation functions for ( alpha ,4n), ( alpha , p3n), ( alpha , alpha n) and ( alpha , alpha 2n) reactions were measured for the first time. (23 refs).

Measurement and analysis of alpha particle induced reactions on yttrium

Energy Technology Data Exchange (ETDEWEB)

Singh, N.L.; Gadkari, M.S. [Baroda Univ. (India). Dept. of Physics; Chintalapudi, S.N. [IUC-DAEF Calcutta Centre, Calcutta (India)

2000-05-01

Excitation functions for {sup 89}Y[({alpha},3n);({alpha},4n);({alpha},p3n);({alpha},{alpha}n);({alpha},{alpha}2n)] reactions were measured up to 50 MeV using stacked foil activation technique and HPGe gamma ray spectroscopy method. The experimental data were compared with calculations considering equilibrium as well as preequilibrium reactions according to the hybrid model of Blann (ALICE/90). For ({alpha},xnyp) type of reactions, the precompound contributions are described by the model. There seems to be indications of direct inelastic scattering effects in ({alpha},{alpha}xn) type of reactions. To the best of our knowledge, the excitation functions for ({alpha},4n), ({alpha},p3n), ({alpha},{alpha}n) and ({alpha},{alpha}2n) reactions were measured for the first time. (orig.)

Molecular cloning and characteristic analysis of a thioredoxin from ...

African Journals Online (AJOL)

Sequence comparison and phylogenetic tree analysis confirmed NmTrx as a distinct member of thioredoxin. Real-time quantitative polymerase chain reaction (PCR) revealed a significantly higher expression of NmTrx transcript in the adult stage compared with the egg and oncomiracidium stages. In the egg and adult ...

Analysis of reaction cross-section production in neutron induced fission reactions on uranium isotope using computer code COMPLET.

Science.gov (United States)

Asres, Yihunie Hibstie; Mathuthu, Manny; Birhane, Marelgn Derso

2018-04-22

This study provides current evidence about cross-section production processes in the theoretical and experimental results of neutron induced reaction of uranium isotope on projectile energy range of 1-100 MeV in order to improve the reliability of nuclear stimulation. In such fission reactions of 235 U within nuclear reactors, much amount of energy would be released as a product that able to satisfy the needs of energy to the world wide without polluting processes as compared to other sources. The main objective of this work is to transform a related knowledge in the neutron-induced fission reactions on 235 U through describing, analyzing and interpreting the theoretical results of the cross sections obtained from computer code COMPLET by comparing with the experimental data obtained from EXFOR. The cross section value of 235 U(n,2n) 234 U, 235 U(n,3n) 233 U, 235 U(n,γ) 236 U, 235 U(n,f) are obtained using computer code COMPLET and the corresponding experimental values were browsed by EXFOR, IAEA. The theoretical results are compared with the experimental data taken from EXFOR Data Bank. Computer code COMPLET has been used for the analysis with the same set of input parameters and the graphs were plotted by the help of spreadsheet & Origin-8 software. The quantification of uncertainties stemming from both experimental data and computer code calculation plays a significant role in the final evaluated results. The calculated results for total cross sections were compared with the experimental data taken from EXFOR in the literature, and good agreement was found between the experimental and theoretical data. This comparison of the calculated data was analyzed and interpreted with tabulation and graphical descriptions, and the results were briefly discussed within the text of this research work. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Low-Energy Nuclear Reactions of Protons in Host Metals at Picometre Distance

International Nuclear Information System (INIS)

Heinrich Hora; George H. Miley; Jak C. Kelly

2000-01-01

A review is given for the explanation of the measurements of Miley (et al.) of a fully reproducible generation of nuclei of the whole periodic table by protons in host metals during a several-weeks reaction. Similar low-energy nuclear reactions (LENR) were observed by other groups. The fact that the heavy nuclides are not due to pollution can be seen from the fact that such very rare elements as thulium and terbium were detected by unique K-shell X-ray spectra. The nuclear reaction energy goes into the heavy nuclei as measured from much bigger traces in CR39 than from alphas. The fact that any reaction of the protons results in stable daughter nuclei is confirmed by the fact that the highest energy gain is resulting with stable reaction products. This has been explained in Ref. 2, and the energy gain for the heavy element generation by a compound reaction was discussed. The explanation is based on the model of the authors from 1989 to assume free motion of the protons contrary to localized crystalline states. A relation of the reaction time U on distance d of the reacting nuclei by a power law with an exponent 34.8 was derived. Based on few reproducible D-D reactions, a reaction time near the range of megaseconds and a reaction distance of nanometers was concluded. A splendid confirmation of the picometre-megasecond reactions was achieved by Li (et al.) from his direct quantum mechanical calculations of the hot fusion D-T reactions based on a one-step selective resonance tunneling model. Li (et al.) were able for the first time to derive the cross sections of the hot fusion. Li's application to picometre distance showed megasecond reaction times with no neutron or gamma emission. Because of the imaginary part in the Schroedinger potential, the problem of the level width is reduced by damping

A mathematical analysis of Prx2-STAT3 disulfide exchange rate constants for a bimolecular reaction mechanism.

Science.gov (United States)

Langford, Troy F; Deen, William M; Sikes, Hadley D

2018-03-22

Appreciation of peroxiredoxins as the major regulators of H 2 O 2 concentrations in human cells has led to a new understanding of redox signaling. In addition to their status as the primary reducers of H 2 O 2 to water, the oxidized peroxiredoxin byproduct of this reaction has recently been shown capable of participation in H 2 O 2 -mediated signaling pathways through disulfide exchange reactions with the transcription factor STAT3. The dynamics of peroxidase-transcription factor disulfide exchange reactions have not yet been considered in detail with respect to how these reactions fit into the larger network of competing reactions in human cells. In this study, we used a kinetic model of oxidation and reduction reactions related to H 2 O 2 metabolism in the cytosol of human cells to study the dynamics of peroxiredoxin-2 mediated oxidation of the redox-regulated transcription factor STAT3. In combination with previously reported experimental data, the model was used to estimate the rate coefficient of a biomolecular reaction between Prx2 and STAT3 for two sets of assumptions that constitute lower and upper bound cases. Using these estimates, we calculated the relative rates of the reaction of oxidized peroxiredoxin-2 and STAT3 and other competing reactions in the cytosol. These calculations revealed that peroxiredoxin-2-mediated oxidation of STAT3 likely occurs at a much slower rate than competing reactions in the cytosol. This analysis suggests the existence of more complex mechanisms, potentially involving currently unknown protein-protein recognition partners, which facilitate disulfide exchange reactions between peroxiredoxin-2 and STAT3. Copyright © 2018 Elsevier Inc. All rights reserved.

Analysis of a Buchwald-Hartwig amination: reaction for pharmaceutical production

DEFF Research Database (Denmark)

Christensen, Henrik

The Buchwald-Hartwig amination reaction is widely used in the production of N-arylated amines in the pharmaceutical industry. The reaction is betweenan aryl halogen and a primary or secondary amine in the presence of a base and a homogeneous catalyst giving the desired N-arylated amine. Due to mild...... is to increase the understanding of the chem­ical reaction mechanisms and kinetics for the Buchwald-Hartwig amination reaction. Also, to develop methods for application of these mechanisms and kinetics to optimize and scale up an organic synthesis to an industrial phar­maceutical production. The Buchwald...

Analysis of a Buckwald-Hartwig amination: reaction for pharmaceutical production

DEFF Research Database (Denmark)

Christensen, Henrik; Kiil, Søren; Dam-Johansen, Kim

The Buchwald-Hartwig amination reaction is widely used in the production of N-arylated amines in the pharmaceutical industry. The reaction is betweenan aryl halogen and a primary or secondary amine in the presence of a base and a homogeneous catalyst giving the desired N-arylated amine. Due to mild...... is to increase the understanding of the chem­ical reaction mechanisms and kinetics for the Buchwald-Hartwig amination reaction. Also, to develop methods for application of these mechanisms and kinetics to optimize and scale up an organic synthesis to an industrial phar­maceutical production. The Buchwald...

On the graph and systems analysis of reversible chemical reaction networks with mass action kinetics

NARCIS (Netherlands)

Rao, Shodhan; Jayawardhana, Bayu; Schaft, Arjan van der

2012-01-01

Motivated by the recent progresses on the interplay between the graph theory and systems theory, we revisit the analysis of reversible chemical reaction networks described by mass action kinetics by reformulating it using the graph knowledge of the underlying networks. Based on this formulation, we

A miniature CSTR cascade for continuous flow of reactions containing solids

OpenAIRE

Mo, Yiming; Jensen, Klavs F

2016-01-01

Continuous handling of solids creates challenges for realizing continuous production of pharmaceuticals and fine chemicals. We present a new miniature continuous stirred-tank reactor (CSTR) cascade to handle solid-forming reactions in flow. Single-phase residence time distribution (RTD) measurements of the CSTR cascade reveal nearly ideal CSTR mixing behavior of the individual units. Consistency of experimental and predicted conversions of a Diels–Alder reaction further confirms the CSTR perf...

High-pressure synthesis of rhombohedral α-AgGaO{sub 2} via direct solid state reaction

Energy Technology Data Exchange (ETDEWEB)

Akhtar, Meysam [Department of Physics and Astronomy, University of Louisville, 102 Natural Science Building, Louisville, KY 40292 (United States); Menon, Madhu [Center for Computational Sciences, University of Kentucky, 325 McVey Hall, Lexington, KY 40506 (United States); Sunkara, Mahendra [Conn Center for Renewable Energy Research, University of Louisville, Ernst Hall Room 102A, Louisville, KY 40292 (United States); Sumanasekera, Gamini [Department of Physics and Astronomy, University of Louisville, 102 Natural Science Building, Louisville, KY 40292 (United States); Conn Center for Renewable Energy Research, University of Louisville, Ernst Hall Room 102A, Louisville, KY 40292 (United States); Durygin, Andriy [Center for the Study of Matter at Extreme Conditions, Florida International University, VH 140, University Park, Miami, FL 33199 (United States); Jasinski, Jacek B., E-mail: jacek.jasinski@louisville.edu [Conn Center for Renewable Energy Research, University of Louisville, Ernst Hall Room 102A, Louisville, KY 40292 (United States)

2015-08-25

Highlights: • Direct synthesis of α-AgGaO{sub 2} via a solid state reaction of Ag{sub 2}O and Ga{sub 2}O{sub 3} powders. • Utilizing high pressure diamond anvil cell to facilitate solid state reaction. • Experimental and theoretical study of vibrational modes for α-AgGaO{sub 2}. • Extensive characterization of synthesized α-AgGaO{sub 2} samples. • GGA + U formalism-based DFT calculations of electronic structure and band gap in α-AgGaO{sub 2}. - Abstract: In this work, we demonstrate the application of high pressure conditions to enable the direct synthesis of α-AgGaO{sub 2} via a solid state reaction of Ag{sub 2}O and Ga{sub 2}O{sub 3}. Synthesis experiments were carried out at pressures and temperatures up to ∼10 GPa and ∼600 °C, respectively, using a resistively-heated diamond anvil cell. Thus synthesized α-AgGaO{sub 2} samples were characterized and their chemical composition and crystal structure were confirmed. In particular, electron diffraction confirmed the rhombohedral delafossite crystal structure of the synthesized AgGaO{sub 2} and its corresponding lattice parameters of a = 2.99 Å and c = 18.43 Å. The vibrational modes analysis was also conducted using a combination of ab initio density functional theory (DFT) and Raman spectroscopy. This analysis yielded good agreement between the calculated Raman-active modes and experimental Raman data. Finally, the application of the GGA + U formalism-based on DFT to calculate the electronic band structure of α-AgGaO{sub 2} provided a more realistic theoretical band gap value than those reported previously.

EXPERIMENTAL CONFIRMATION FOR SELECTION OF IRRADIATION REGIMENS FOR INTRAPERITONEAL PHOTODYNAMIC THERAPY WITH PORPHYRIN AND PHTHALOCYANINE PHOTOSENSITIZERS

Directory of Open Access Journals (Sweden)

A. A. Pankratov

2017-01-01

Full Text Available Optimized irradiation regimens for intraperitoneal photodynamic therapy with porphyrin and phthalocyanine photosensitizers are determined in in vitro and in vivo studies.The experimental  study on НЕр2 cell line showed that reduce of power density for constant  light dose increased significantly the efficacy of photodynamic therapy (the reduce of power density from 20-80 mW/cm2 to 10 mW/cm2 had the same results (90% cell death for half as much concentration of the photosensitizer.The obtained results were confirmed in vivo in mice with grafted tumor S-37. For light dose of 90 J/cm2  and power density of 25 mW/cm2 none of animals in the experimental  group had total resorption of the tumor. For the same light dose and decrease  of power density to 12 mW/cm2  total tumor resorption was achieved in 34% of animals, 66% of animals died from phototoxic  shock. For twofold decrease  of light dose – to 45 J/cm2  with the same low-intensity power density (12 mW/cm2 we managed total tumor resorption in 100% of animals.In the following studies of optimized irradiation regimen for intrapleural photodynamic therapy the reaction of intact peritoneum of rats on photodynamic exposure was assessed and optimized parameters of laser irradiation, which did not cause necrosis and intense inflammatory reaction of peritoneum, were determined – light dose of 10 J/cm2  with power density of mW/cm2.Thus, the reasonability for use of low-intensity regimens of irradiation for intraperitoneal photodynamic therapy was confirmed experimentally with possibility of high efficacy of treatment without inflammatory reactions of peritoneum.

Department of Nuclear Reaction - Overview

International Nuclear Information System (INIS)

Budzanowski, A.

2002-01-01

a Ph.D. thesis of M. Wojcik. The Random Matrix Theory was successfully applied to the analysis of behaviour of the complex systems like human brain and stock exchange. It was found that the dynamics of the financial correlations can be treated by the matrix representation in analogy to the collective states in nuclear systems. Shell model calculations extended to the continuum were performed for neutron-rich oxygen and fluorine isotopes. Calculations were made for mirror decays 17 N(β + ) 17 F and 17 N(β - ) 17 O. Influence of the dd μ and dt μ resonance states on the rate of thermofusion reactions was estimated. New experiments performed by the KEK-RIKEN-RAL confirmed the predicted by us effect of the difference in deuteron fussion in condensed ortho-D 2 and para-D 2 . Studies of the pion-pion interaction above resonance region were performed. Both soft (nonperturbative) and hard (perturbative) processes were studied. It was shown that the assumption of Regge factorization leads to a good description of the total cross section data for π + π + and π - π - scattering. The onset of pQCD effects was carefully analysed. We have published over 50 papers in respectable international journals. Our staff member participated to 30 international conferences. Our main collaboration partners were: JINR (Dubna), FZ Juelich, BNL Brookhaven, GSI Darmstadt and University of Lund as well as Jagiellonian University and Technical University of Mining and Metallurgy (Cracow). (author)

Confirmation of molecular formulas of metallic complexes through X-ray fluorescence quantitative analysis

International Nuclear Information System (INIS)

Filgueiras, C.A.L.; Marques, E.V.; Machado, R.M.

1984-01-01

X-ray fluorescence spectrophotometry was employed to determined the metal content in a series of five transition element complexes (Mn, Ti, Zn, V). The results confirmed the molecular formulas of these complexes, already proposed on the basis of elemental microanalysis, solution condutimetry and other analytical methods. (C.L.B.) [pt

Analysis of gas absorption to a thin liquid film in the presence of a zero-order chemical reaction

Science.gov (United States)

Rajagopalan, S.; Rahman, M. M.

1995-01-01

The paper presents a detailed theoretical analysis of the process of gas absorption to a thin liquid film adjacent to a horizontal rotating disk. The film is formed by the impingement of a controlled liquid jet at the center of the disk and subsequent radial spreading of liquid along the disk. The chemical reaction between the gas and the liquid film can be expressed as a zero-order homogeneous reaction. The process was modeled by establishing equations for the conservation of mass, momentum, and species concentration and solving them analytically. A scaling analysis was used to determine dominant transport processes. Appropriate boundary conditions were used to solve these equations to develop expressions for the local concentration of gas across the thickness of the film and distributions of film height, bulk concentration, and Sherwood number along the radius of the disk. The partial differential equation for species concentration was solved using the separation of variables technique along with the Duhamel's theorem and the final analytical solution was expressed using confluent hypergeometric functions. Tables for eigenvalues and eigenfunctions are presented for a number of reaction rate constants. A parametric study was performed using Reynolds number, Ekman number, and dimensionless reaction rate as parameters. At all radial locations, Sherwood number increased with Reynolds number (flow rate) as well as Ekman number (rate of rotation). The enhancement of mass transfer due to chemical reaction was found to be small when compared to the case of no reaction (pure absorption), but the enhancement factor was very significant when compared to pure absorption in a stagnant liquid film. The zero-order reaction processes considered in the present investigation included the absorption of oxygen in aqueous alkaline solutions of sodiumdithionite and rhodium complex catalyzed carbonylation of methanol. Present analytical results were compared to previous theoretical

Exploring conditions for the enhancement of acene semiconductors through the use of the Diels-alder reaction

Science.gov (United States)

Qualizza, Brittni A.

This dissertation demonstrates the application of SAMs to the surface of acene crystals, specifically of tetracene and rubrene, using the Diels-Alder reaction. The second chapter details preliminary reaction results and two analytical methods which were employed to confirm adsorption of the dienophile on the surface of single crystals, tetracene and rubrene. These were mass spectrometry and X-ray photoelectron spectroscopy (XPS). Mass spectrometry experiments distinguish the chemical identity of adduct on the crystals and also it discerned chemi- and physisorbed molecules from one another. XPS was used to prove face selectivity of the reaction by the detection of dichloromaleic anhydride. From a mechanistic standpoint, this system demonstrated unusual steric effects: the reaction of one face of the tetracene crystal was virtually inert, while another face was facile. The dienophiles' steric bulk was also expected to play critical role for these confined systems, however analysis of surface data was hindered by the relative lack of corresponding solution kinetic data. While the rate of anthracene's reaction has been studied extensively with a range of dienophiles and tetracene/pentacene has been studied theoretically (with limited experimental reports), an expansive report was generated to aid in future interpretations of acene systems. These kinetic results constitute chapter three.

Fabrication of a pen-shaped portable biochemical reaction system based on magnetic bead manipulation

International Nuclear Information System (INIS)

Shikida, Mitsuhiro; Inagaki, Noriyuki; Okochi, Mina; Honda, Hiroyuki; Sato, Kazuo

2011-01-01

A pen-shaped platform that is similar to a mechanical pencil is proposed for producing a portable reaction system. A reaction unit, as the key component in the system, was produced by using a heat shrinkable tube. A mechanical pencil supplied by Mitsubishi Pencil Co. Ltd was used as the pen-shaped platform for driving the reaction cylinder. It was actuated using an inchworm motion. We confirmed that the magnetic beads were successfully manipulated in the droplet in the cylinder-shaped reaction units. (technical note)

Catalytic Upgrading of Biomass-Derived Compounds via C-C Coupling Reactions. Computational and Experimental Studies of Acetaldehyde and Furan Reactions in HZSM-5

Energy Technology Data Exchange (ETDEWEB)

Liu, Cong [Argonne National Lab. (ANL), Argonne, IL (United States); Evans, Tabitha J. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Cheng, Lei [Argonne National Lab. (ANL), Argonne, IL (United States); Nimlos, Mark R. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Mukarakate, Calvin [National Renewable Energy Lab. (NREL), Golden, CO (United States); Robichaud, David J. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Assary, Rajeev S. [Argonne National Lab. (ANL), Argonne, IL (United States); Curtiss, Larry A. [Argonne National Lab. (ANL), Argonne, IL (United States)

2015-10-02

These catalytic C–C coupling and deoxygenation reactions are essential for upgrading of biomass-derived oxygenates to fuel-range hydrocarbons. Detailed understanding of mechanistic and energetic aspects of these reactions is crucial to enabling and improving the catalytic upgrading of small oxygenates to useful chemicals and fuels. Using periodic density functional theory (DFT) calculations, we have investigated the reactions of furan and acetaldehyde in an HZSM-5 zeolite catalyst, a representative system associated with the catalytic upgrading of pyrolysis vapors. Comprehensive energy profiles were computed for self-reactions (i.e., acetaldehyde coupling and furan coupling) and cross-reactions (i.e., acetaldehyde + furan) of this representative mixture. Major products proposed from the computations are further confirmed using temperature controlled mass spectra measurements. Moreover, the computational results show that furan interacts with acetaldehyde in HZSM-5 via an alkylation mechanism, which is more favorable than the self-reactions, indicating that mixing furans with aldehydes could be a promising approach to maximize effective C–C coupling and dehydration while reducing the catalyst deactivation (e.g., coke formation) from aldehyde condensation.

A female Viking warrior confirmed by genomics.

Science.gov (United States)

Hedenstierna-Jonson, Charlotte; Kjellström, Anna; Zachrisson, Torun; Krzewińska, Maja; Sobrado, Veronica; Price, Neil; Günther, Torsten; Jakobsson, Mattias; Götherström, Anders; Storå, Jan

2017-12-01

The objective of this study has been to confirm the sex and the affinity of an individual buried in a well-furnished warrior grave (Bj 581) in the Viking Age town of Birka, Sweden. Previously, based on the material and historical records, the male sex has been associated with the gender of the warrior and such was the case with Bj 581. An earlier osteological classification of the individual as female was considered controversial in a historical and archaeological context. A genomic confirmation of the biological sex of the individual was considered necessary to solve the issue. Genome-wide sequence data was generated in order to confirm the biological sex, to support skeletal integrity, and to investigate the genetic relationship of the individual to ancient individuals as well as modern-day groups. Additionally, a strontium isotope analysis was conducted to highlight the mobility of the individual. The genomic results revealed the lack of a Y-chromosome and thus a female biological sex, and the mtDNA analyses support a single-individual origin of sampled elements. The genetic affinity is close to present-day North Europeans, and within Sweden to the southern and south-central region. Nevertheless, the Sr values are not conclusive as to whether she was of local or nonlocal origin. The identification of a female Viking warrior provides a unique insight into the Viking society, social constructions, and exceptions to the norm in the Viking time-period. The results call for caution against generalizations regarding social orders in past societies. © 2017 The Authors American Journal of Physical Anthropology Published by Wiley Periodicals, Inc.

Predictors of chronic ankle instability: Analysis of peroneal reaction time, dynamic balance and isokinetic strength.

Science.gov (United States)

Sierra-Guzmán, Rafael; Jiménez, Fernando; Abián-Vicén, Javier

2018-05-01

Previous studies have reported the factors contributing to chronic ankle instability, which could lead to more effective treatments. However, factors such as the reflex response and ankle muscle strength have not been taken into account in previous investigations. Fifty recreational athletes with chronic ankle instability and 55 healthy controls were recruited. Peroneal reaction time in response to sudden inversion, isokinetic evertor muscle strength and dynamic balance with the Star Excursion Balance Test and the Biodex Stability System were measured. The relationship between the Cumberland Ankle Instability Tool score and performance on each test was assessed and a backward multiple linear regression analysis was conducted. Participants with chronic ankle instability showed prolonged peroneal reaction time, poor performance in the Biodex Stability System and decreased reach distance in the Star Excursion Balance Test. No significant differences were found in eversion and inversion peak torque. Moderate correlations were found between the Cumberland Ankle Instability Tool score and the peroneal reaction time and performance on the Star Excursion Balance Test. Peroneus brevis reaction time and the posteromedial and lateral directions of the Star Excursion Balance Test accounted for 36% of the variance in the Cumberland Ankle Instability Tool. Dynamic balance deficits and delayed peroneal reaction time are present in participants with chronic ankle instability. Peroneus brevis reaction time and the posteromedial and lateral directions of the Star Excursion Balance Test were the main contributing factors to the Cumberland Ankle Instability Tool score. No clear strength impairments were reported in unstable ankles. Copyright © 2018 Elsevier Ltd. All rights reserved.

Effects of self-schema elaboration on affective and cognitive reactions to self-relevant information.

Science.gov (United States)

Petersen, L E; Stahlberg, D; Dauenheimer, D

2000-02-01

The basic assumption of the integrative self-schema model (ISSM; L.-E. Petersen, 1994; L.-E. Petersen, D. Stahlberg, & D. Dauenheimer, 1996; D. Stahlberg, L.-E. Petersen, & D. Dauenheimer, 1994, 1999) is that self-schema elaboration (schematic vs. aschematic) affects reactions to self-relevant information. This assumption is based on the idea that schematic dimensions occupy a more central position in the cognitive system than aschematic dimensions. In the first study, this basic prediction could be clearly confirmed: The results showed that schematic dimensions possessed stronger cognitive associations with other self-relevant cognitions as well as a higher resistance to change than aschematic dimensions did. In the second study, the main assumptions of the ISSM concerning the affective and cognitive reactions to self-relevant feedback were tested: The ISSM proposes that, on schematic dimensions, reactions to self-relevant feedback will most likely follow principles of self-consistency theory, whereas on aschematic dimensions positive feedback should elicit the most positive reactions that self-enhancement theory would predict. The experimental results clearly confirmed the hypotheses derived from the ISSM for affective reactions. Cognitive reactions, however, were in line with self-consistency principles and were not modified by the elaboration of the self-schema dimension involved.

Heavy ion transfer reactions

International Nuclear Information System (INIS)

Weisser, D.C.

1977-06-01

To complement discussions on the role of γ rays in heavy ion induced reactions, the author discusses the role played by particle detection. Transfer reactions are part of this subject and are among those in which one infers the properties of the residual nucleus in a reaction by observing the emerging light nucleus. Inelastic scattering ought not be excluded from this subject, although no particles are transferred, because of the role it plays in multistep reactions and in fixing O.M. parameters describing the entrance channel of the reaction. Heavy ion transfer reaction studies have been under study for some years and yet this research is still in its infancy. The experimental techniques are difficult and the demands on theory rigorous. One of the main products of heavy ion research has been the thrust to re-examine the assumptions of reaction theory and now include many effects neglected for light ion analysis. This research has spurred the addition of multistep processes to simple direct processes and coupled channel calculations. (J.R.)

Particle spectra and correlations in sulfur-nucleus reactions at 200 GeV per nucleon

International Nuclear Information System (INIS)

Alber, T.

1995-08-01

In this work the production of negatively charged particles and two-particle correlations in nucleus-nucleus reactions at high energies are studied. The range of the acceptance of experiment NA35 at the CERN-SPS was increased in 1990 by adding a large volume Time Projection Chamber downstream of the streamer chamber. The analysis of the data taken during the run period 1991 shows that such a detector faces no basic problems when operated in a high multiplicity experiment. The scenario of particle production in sulfur-nucleus reactions is studied via the measurement of rapidity and transverse momentum distributions which show good agreement with the results from other data-sets of the same experiment. The width of the rapidity distribution is only a little narrower than observed in nucleon-nucleon collisions and is in contradiction to the assumption of a static source with isotropic particle emission. The shape of the transverse momentum distribution indicates an effective temperature at freeze-out of about 150 MeV. The analysis of the two-particle correlation benefits particularly from the high statistics collected for different reactions in different phase-space regions. This allows a differential analysis of the correlation function for the different components of the momentum difference in various regions of rapidity and transverse momentum. It is recalled that for an expanding source the experimentally obtained radius parameters are not a direct measure of the geometrical size of the source but measure a so-called region of homogeneity. This expectation is also confirmed by a microscopic simulation of the reaction. The experimental results for the radius parameters support such a description of the particle production mechanism in terms of an expanding source. (orig.)

Neutron transfer reactions in the fp-shell region

Energy Technology Data Exchange (ETDEWEB)

Mahgoub, Mahmoud

2008-06-26

Neutron transfer reactions were used to study the stability of the magic number N=28 near {sup 56}Ni. On one hand the one-neutron pickup (d,p) reaction was used for precision spectroscopy of single-particle levels in {sup 55}Fe. On the other hand we investigated the two-neutron transfer mechanism into {sup 56}Ni using the pickup reaction {sup 58}Ni((vector)p,t){sup 56}Ni. In addition the reliability of inverse kinematics reactions at low energy to study exotic nuclei was tested by the neutron transfer reactions t({sup 40}Ar,p){sup 42}Ar and d({sup 54}Fe,p){sup 55}Fe using tritium and deuterium targets, respectively, and by comparing the results with those of the normal kinematics reactions. The experimental data, differential cross-section and analyzing powers, are compared to DWBA and coupled channel calculations utilizing the code CHUCK3. By performing the single-neutron stripping reaction ((vector)d,p) on {sup 54}Fe the 1f{sub 7/2} shell in the ground state configuration was found to be partly broken. The instability of the 1f{sub 7/2} shell and the magic number N=28 was confirmed once by observing a number of levels with J{sup {pi}} = 7/2{sup -} at low excitation energies, which should not be populated if {sup 54}Fe has a closed 1f{sub 7/2} shell, and also by comparing our high precision experimental data with a large scale shell model calculation using the ANTOINE code [5]. Calculations including a partly broken 1f{sub 7/2} shell show better agreement with the experiment. The instability of the 1f{sub 7/2} shell was confirmed also by performing the two-neutron pick-up reaction ((vector)p,t) on {sup 58}Ni to study {sup 56}Ni, where a considerable improvement in the DWBA calculation was observed after considering 1f{sub 7/2} as a broken shell. To prove the reliability of inverse kinematics transfer reactions at low energies ({proportional_to} 2 AMeV), the aforementioned single-neutron transfer reaction (d,p) was repeated using a beam of {sup 54}Fe ions and a

Detailed analysis of allergic cutaneous reactions to spinal cord stimulator devices

Directory of Open Access Journals (Sweden)

Chaudhry ZA

2013-08-01

Full Text Available Zeshan Ahmed Chaudhry,1 Umer Najib,2 Zahid H Bajwa,3 W Carl Jacobs,4 Javed Sheikh,5 Thomas T Simopoulos61Department of Diagnostic and Interventional Neuroradiology, Massachusetts General Hospital/Harvard Medical School, Boston, MA, USA; 2Department of Neurology, Robert C Byrd Health Sciences Center of West Virginia University, Morgantown, WV, USA; 3Boston Headache Institute, Waltham, MA, USA; 4Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA; 5Department of Medicine, Allergy and Immunology, 6Department of Anesthesia, Beth Israel Deaconess Medical Center, Brookline, MA, USAAbstract: The use of spinal cord stimulation (SCS devices to treat chronic, refractory neuropathic pain continues to expand in application. While device-related complications have been well described, inflammatory reactions to the components of these devices remain underreported. In contrast, hypersensitivity reactions associated with other implanted therapies, such as endovascular and cardiac rhythm devices, have been detailed. The purpose of this case series is to describe the clinical presentation and course of inflammatory reactions as well as the histology of these reactions. All patients required removal of the entire device after developing inflammatory reactions over a time course of 1–3 months. Two patients developed a foreign body reaction in the lead insertion wound as well as at the implantable pulse generator site, with histology positive for giant cells. One patient developed an inflammatory dermatitis on the flank and abdomen that resolved with topical hydrocortisone. “In vivo” testing with a lead extension fragment placed in the buttock resulted in a negative reaction followed by successful reimplantation of an SCS device. Inflammatory reactions to SCS devices can manifest as contact dermatitis, granuloma formation, or foreign body reactions with giant cell formation. Tissue diagnosis is essential, and

Analysis of the nucleon-nucleus reactions by the quantum molecular dynamics

International Nuclear Information System (INIS)

Chiba, Satoshi; Niita, Koji; Maruyama, Toshiki; Fukahori, Tokio; Takada, Hiroshi; Iwamoto, Akira

1995-01-01

The quantum molecular dynamics + statistical decay model has been applied to analyze the nucleon-induced nuclear reactions in the energy range from 50 to 3 GeV in order to verify its applicability to light-ion induced nuclear reactions. It was found that the present approach could give a quantitative description of various cross sections such as (p,p'), (p,n), (n,p) reactions from a wide range of targets and also target-like isotope production cross sections from p+Fe reaction, showing its basic ability as a tool for the study of intermediate energy nuclear reactions and nuclear data evaluation. (author)

Free Energy Contribution Analysis Using Response Kernel Approximation: Insights into the Acylation Reaction of a Beta-Lactamase.

Science.gov (United States)

Asada, Toshio; Ando, Kanta; Bandyopadhyay, Pradipta; Koseki, Shiro

2016-09-08

A widely applicable free energy contribution analysis (FECA) method based on the quantum mechanical/molecular mechanical (QM/MM) approximation using response kernel approaches has been proposed to investigate the influences of environmental residues and/or atoms in the QM region on the free energy profile. This method can evaluate atomic contributions to the free energy along the reaction path including polarization effects on the QM region within a dramatically reduced computational time. The rate-limiting step in the deactivation of the β-lactam antibiotic cefalotin (CLS) by β-lactamase was studied using this method. The experimentally observed activation barrier was successfully reproduced by free energy perturbation calculations along the optimized reaction path that involved activation by the carboxylate moiety in CLS. It was found that the free energy profile in the QM region was slightly higher than the isolated energy and that two residues, Lys67 and Lys315, as well as water molecules deeply influenced the QM atoms associated with the bond alternation reaction in the acyl-enzyme intermediate. These facts suggested that the surrounding residues are favorable for the reactant complex and prevent the intermediate from being too stabilized to proceed to the following deacylation reaction. We have demonstrated that the free energy contribution analysis should be a useful method to investigate enzyme catalysis and to facilitate intelligent molecular design.

Deformation behaviour of {gamma}+{alpha}{sub 2} Ti aluminide processed through reaction synthesis

Energy Technology Data Exchange (ETDEWEB)

Gupta, R.K., E-mail: rohitkumar_gupta@vssc.gov.in [Vikram Sarabhai Space Centre, ISRO, Trivandrum, Kerala 695 022 (India); Pant, Bhanu [Vikram Sarabhai Space Centre, ISRO, Trivandrum, Kerala 695 022 (India); Kumar, Vinod [SAIL-RDCIS, Ranchi (India); Agarwala, Vijaya [Indian Institute of Technology, Roorkee 247 667 (India); Sinha, P.P. [Vikram Sarabhai Space Centre, ISRO, Trivandrum, Kerala 695 022 (India)

2013-01-01

{gamma}+{alpha}{sub 2} titanium aluminide alloys made through reaction synthesis have been used for deformation study. Hot isothermal compression test is carried out to study the deformation characteristics of the alloys using Gleeble thermomechanical simulator. Three alloys based on Ti48Al2Cr2Nb0.1B (at%) are tested at different temperatures and at different strain rates. True stress-true strain plots are analyzed along with analysis of tested specimens. Tested specimens are observed under optical and electron microscopes. Presence of various deformation morphologies and phases were confirmed. Microhardness evaluation and transmission electron microscopic examination are used to confirm the presence of different phases. It is found that dynamic recrystallization is mainly playing role in deformation of these alloys. Presence of dynamically recrystallized (DRX) grains and lamellar microstructures is confirmed at the intergranular area and inside the grains, respectively. A nucleation model is suggested for DRX and lamellar grain nucleation during deformation. Attempt has been made to quantify the presence of various phases through optical microscopy. Hot workability map is also suggested on the basis of microstructural and visual observation of compression tested specimens.

Amazing variational approach to chemical reactions

OpenAIRE

Fernández, Francisco M.

2009-01-01

In this letter we analyse an amazing variational approach to chemical reactions. Our results clearly show that the variational expressions are unsuitable for the analysis of empirical data obtained from chemical reactions.

Theoretical considerations of Flow Injection Analysis in the Absence of Chemical Reactions

DEFF Research Database (Denmark)

Andersen, Jens Enevold Thaulov

2000-01-01

The fundamental mechanism of flow injection analysis (FIA) is assumed to be simple dissusion and the response of the detector is included in a model description that provide information about the shape of the FIA peak in terms of, basically, five parameters. Two of the five parameters are associa...... that any deviation from the features of the present model and the results of a tentative chemical reaction with one of the test compounds, is related to chemical kinetics.......The fundamental mechanism of flow injection analysis (FIA) is assumed to be simple dissusion and the response of the detector is included in a model description that provide information about the shape of the FIA peak in terms of, basically, five parameters. Two of the five parameters...

Influence of irradiation on reaction products of nitrite in foodstuffs

International Nuclear Information System (INIS)

Mirna, A.; Rau, G.

1982-01-01

Nitro alkanes and nitrolic acids are formed in foods by nitrosation reactions with nitrite. Among TEA-responsive compounds nitrolic acid behave to irradiation similar to N-nitrosamines. Some substances, extracted from spices, especially garlic, are also detectable by GC/TEA-chromatogramms of meat products and of reaction products from spices with nitrite show retention times not always clearly differentiated from those of NDMA, NDEA, NPIP and NPYR, respectively. Additional confirmation of such TEA positive compounds, therefore, is necessary. (orig.) [de

Synthesis and electrocatalytic activity towards oxygen reduction reaction of gold-nanostars

OpenAIRE

Oyunbileg G; Batnyagt G; Enkhsaruul B; T Takeguchi

2018-01-01

The oxygen reduction reaction (ORR) is a characteristic reaction which determines the performance of fuel cells which convert a chemical energy into an electrical energy. Aims of this study are to synthesize Au-based nanostars (AuNSs) and determine their preliminary electro-catalytic activities towards ORR by a rotating-disk electrode method in alkaline electrolyte. The images obtained from a scanning electron microscope (SEM) and a transmission electron microscope (TEM) analyses confirm the ...

Study of the (p,d3He) reaction as a quasi-free reaction process

International Nuclear Information System (INIS)

Cowley, A.A.; Roos, P.G.; Chant, N.S.; Woody, R. III; Holmgren, H.D.; Goldberg, D.A.

1976-11-01

The (p,d 3 He) reaction on 6 Li, 7 Li, 9 Be, and 12 C has been investigated in conjunction with studies of the (p,pα) reaction on the same targets. Coincident data for all four targets were obtained at a bombarding energy of 100 MeV for numerous angle pairs in order to test the reaction mechanism. Comparisons of the (p,d 3 He) data to both (p,pα) data and distorted wave impulse approximation calculations (DWIA) indicate a dominance of the direct quasi-free reaction process (p + alpha yields d + 3 He). The absolute alpha-particle spectroscopic factors extracted using DWIA analysis are in agreement with the values obtained in the (p,pα) reaction

[Pulmonary reaction after furazidin (Furagin). Case report].

Science.gov (United States)

Zielonka, T M; Demkow, U; Kuś, J

1997-05-01

For the first time in Poland we present the case of pulmonary reaction to furazidin which is by chemical structure closely related to nitrofurantoin. 63 years old woman presented generalized symptoms of acute hypersensitivity reaction induced by furazidin as well as features of chronic pulmonary fibrosis. After few months of treatment with this drug patients complained of weight loss, dyspnea on effort, non-productive cough, chills and fever. Radiological and functional evaluation of respiratory system confirmed features of lung fibrosis. Drug provocation test was positive. In vitro furazidin in low concentrations stimulated proliferation of patient's lymphocytes. After cessation of treatment we have observed rapid improvement of clinical, radiological, biochemical and functional parameters.

Stochastic simulation of biological reactions, and its applications for studying actin polymerization.

Science.gov (United States)

Ichikawa, Kazuhisa; Suzuki, Takashi; Murata, Noboru

2010-11-30

Molecular events in biological cells occur in local subregions, where the molecules tend to be small in number. The cytoskeleton, which is important for both the structural changes of cells and their functions, is also a countable entity because of its long fibrous shape. To simulate the local environment using a computer, stochastic simulations should be run. We herein report a new method of stochastic simulation based on random walk and reaction by the collision of all molecules. The microscopic reaction rate P(r) is calculated from the macroscopic rate constant k. The formula involves only local parameters embedded for each molecule. The results of the stochastic simulations of simple second-order, polymerization, Michaelis-Menten-type and other reactions agreed quite well with those of deterministic simulations when the number of molecules was sufficiently large. An analysis of the theory indicated a relationship between variance and the number of molecules in the system, and results of multiple stochastic simulation runs confirmed this relationship. We simulated Ca²(+) dynamics in a cell by inward flow from a point on the cell surface and the polymerization of G-actin forming F-actin. Our results showed that this theory and method can be used to simulate spatially inhomogeneous events.

Stochastic simulation of biological reactions, and its applications for studying actin polymerization

International Nuclear Information System (INIS)

Ichikawa, Kazuhisa; Suzuki, Takashi; Murata, Noboru

2010-01-01

Molecular events in biological cells occur in local subregions, where the molecules tend to be small in number. The cytoskeleton, which is important for both the structural changes of cells and their functions, is also a countable entity because of its long fibrous shape. To simulate the local environment using a computer, stochastic simulations should be run. We herein report a new method of stochastic simulation based on random walk and reaction by the collision of all molecules. The microscopic reaction rate P r is calculated from the macroscopic rate constant k. The formula involves only local parameters embedded for each molecule. The results of the stochastic simulations of simple second-order, polymerization, Michaelis–Menten-type and other reactions agreed quite well with those of deterministic simulations when the number of molecules was sufficiently large. An analysis of the theory indicated a relationship between variance and the number of molecules in the system, and results of multiple stochastic simulation runs confirmed this relationship. We simulated Ca 2+ dynamics in a cell by inward flow from a point on the cell surface and the polymerization of G-actin forming F-actin. Our results showed that this theory and method can be used to simulate spatially inhomogeneous events

Structural analysis of CuO / CeO2-based catalytic materials intended for PROX reaction: Part I

International Nuclear Information System (INIS)

Neiva, L.S.; Simoes, A.N.; Bispo, A.; Ribeiro, M.A.; Gama, L.

2011-01-01

This work relates the synthesis process of CuO/CeO 2 catalytic materials by a combustion reaction method as well as it introduces a structural analysis of the developed material, this structural analysis had as main focus to evaluate the influence of the doping substance (CuO) when being incorporated in the hostess matrix structure that is CeO 2 . The CuO/CeO catalytic materials developed in this work are destined to preferential oxidation of CO reaction (PROX). The developed materials were characterized by XRD, SEM and textural complete analysis by the BET method. According to the results, the CuO incorporation changed crystallinity of the structure of the catalytic materials. On the other hand, the morphologic and textural characteristics did not showed significant differences regarding the presence of the doping substance (CuO) in the structure of the developed materials. The porosity of the structures of the developed catalytic materials belongs to the type macroporous. (author)

Bayesian inversion analysis of nonlinear dynamics in surface heterogeneous reactions.

Science.gov (United States)

Omori, Toshiaki; Kuwatani, Tatsu; Okamoto, Atsushi; Hukushima, Koji

2016-09-01

It is essential to extract nonlinear dynamics from time-series data as an inverse problem in natural sciences. We propose a Bayesian statistical framework for extracting nonlinear dynamics of surface heterogeneous reactions from sparse and noisy observable data. Surface heterogeneous reactions are chemical reactions with conjugation of multiple phases, and they have the intrinsic nonlinearity of their dynamics caused by the effect of surface-area between different phases. We adapt a belief propagation method and an expectation-maximization (EM) algorithm to partial observation problem, in order to simultaneously estimate the time course of hidden variables and the kinetic parameters underlying dynamics. The proposed belief propagation method is performed by using sequential Monte Carlo algorithm in order to estimate nonlinear dynamical system. Using our proposed method, we show that the rate constants of dissolution and precipitation reactions, which are typical examples of surface heterogeneous reactions, as well as the temporal changes of solid reactants and products, were successfully estimated only from the observable temporal changes in the concentration of the dissolved intermediate product.

Depressurization accident analysis of MPBR by PBRSIM with chemical reaction model

International Nuclear Information System (INIS)

No, Hee Cheon; Kadak, A. C.

2002-01-01

The simple model for natural circulation is implemented into PBR S IM to provide air inlet velocity from the containment air space. For the friction and form loss only the pebble region is considered conservatively modeling laminar flow through a packed bed. For the chemical reaction model of PBR S IM the oxidation rate is determined as the minimum value of three mechanisms estimated at each time step: oxygen mass flow rate entering the bottom of the reflector, oxidation rate by kinetics, and oxygen mass flow rate arriving at the graphite surface by diffusion. Oxygen mass flux arriving at the graphite surface by diffusion is estimated based on energy-mass analogy. Two types of exothermic chemical reaction are considered: (C + zO 2 → xCO + yCO 2 ) and (2CO + O 2 2CO 2 ). The heterogeneous and homogeneous chemical reaction rates by kinetics are determined by INEEL and Bruno correlations, respectively. The instantaneous depressurization accident of MPBR is simulated using PBR S IM with chemical model. The air inlet velocity is initially rapidly dropped within 10 hr and reaches a saturation value of about 1.5cm/s. The oxidation rate by the diffusion process becomes lower than that by the chemical kinetics above 600K. The maximum pebble bed temperatures without and with chemical reaction reach the peak values of 1560 and 1617 .deg. C at 80 hr and 92 hr, respectively. As the averaged temperatures in the bottom reflector and the pebble bed regions increase with time, (C+1/2O2 ->CO) reaction becomes dominant over (C+O 2 →CO 2 ) reaction. Also, the CO generated by (C+1/2O 2 →CO) reaction will be consumed by (2CO+O 2 →2CO 2 ) reaction and the energy homogeneously generated by this CO depletion reaction becomes dominant over the heterogeneous reaction

On-line Analysis of Catalytic Reaction Products Using a High-Pressure Tandem Micro-reactor GC/MS.

Science.gov (United States)

Watanabe, Atsushi; Kim, Young-Min; Hosaka, Akihiko; Watanabe, Chuichi; Teramae, Norio; Ohtani, Hajime; Kim, Seungdo; Park, Young-Kwon; Wang, Kaige; Freeman, Robert R

2017-01-01

When a GC/MS system is coupled with a pressurized reactor, the separation efficiency and the retention time are directly affected by the reactor pressure. To keep the GC column flow rate constant irrespective of the reaction pressure, a restrictor capillary tube and an open split interface are attached between the GC injection port and the head of a GC separation column. The capability of the attached modules is demonstrated for the on-line GC/MS analysis of catalytic reaction products of a bio-oil model sample (guaiacol), produced under a pressure of 1 to 3 MPa.

Sensitive inexpensive spectrophotometric and spectrofluorimetric analysis of ezogabine, levetiracetam and topiramate in tablet formulations using Hantzsch condensation reaction

Science.gov (United States)

Ibrahim, F. A.; El-Yazbi, A. F.; Wagih, M. M.; Barary, M. A.

2017-09-01

Two highly sensitive, simple and selective spectrophotometric and spectrofluorimetric assays have been investigated for the analysis of ezogabine, levetiracetam and topiramate in their pure and in pharmaceutical dosage forms. The suggested methods depend on the condensation of the primary amino-groups in the three drugs with acetylacetone and formaldehyde according to Hantzsch reaction yielding highly fluorescent yellow colored dihydropyridine derivatives. The reaction products of ezogabine, levetiracetam and topiramate were measured spectrophotometrically at 418, 390 and 380 nm or spectrofluorimetrically at λem/ex of 495/425 nm, 490/415 nm and 488/410 nm, respectively. Various experimental conditions have been carefully studied to maximize the reaction yield. At the optimum reaction conditions, the calibration curves were rectilinear over the concentration ranges of 8-25, 60-180 and 80-200 μg/mL spectrophotometrically and 0.02-0.2, 0.2-1.2 and 0.2-1.5 μg/mL spectrofluorimetrically for ezogabine, levetiracetam and topiramate, respectively with good correlation coefficients. The suggested methods were applied successfully for the analysis of ezogabine, levetiracetam and topiramate in their commercial tablets with high percentage recoveries and negligible interference from various excipients in pharmaceutical dosage forms. The results were statistically analyzed and showed the absence of any significant difference between both developed and published methods. The procedures were validated and evaluated by the ICH guidelines revealing good reproducibility and accuracy. Therefore, the two proposed methods may be considered of high interest for practical and reliable analysis of ezogabine, levetiracetam and topiramate in pharmaceutical dosage forms.

Security analysis with improved design of post-confirmation mechanism for quantum sealed-bid auction with single photons

Science.gov (United States)

Zhang, Ke-Jia; Kwek, Leong-Chuan; Ma, Chun-Guang; Zhang, Long; Sun, Hong-Wei

2018-02-01

Quantum sealed-bid auction (QSA) has been widely studied in quantum cryptography. For a successful auction, post-confirmation is regarded as an important mechanism to make every bidder verify the identity of the winner after the auctioneer has announced the result. However, since the auctioneer may be dishonest and collude with malicious bidders in practice, some potential loopholes could exist. In this paper, we point out two types of collusion attacks for a particular post-confirmation technique with EPR pairs. And it is not difficult to see that there exists no unconditionally secure post-confirmation mechanism in the existing QSA model, if the dishonest participants have the ability to control multiparticle entanglement. In the view of this, we note that some secure implementation could exist if the participants are supposed to be semi-quantum, i.e., they can only control single photons. Finally, two potential methods to design post-confirmation mechanism are presented in this restricted scenario.

Reaction parameters for controlled sonosynthesis of gold nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Gonzalez M, A. L. [Universidad Autonoma del Estado de Mexico, Facultad de Quimica, Paseo Colon esq. Paseo Tollocan s/n, 50120 Toluca, Estado de Mexico (Mexico); Cabrera L, L. I. [UNAM-UAEM, Centro Conjunto de Investigacion en Quimica Sustentable, Km 14.5 Carretera Toluca-Atlacomulco, 50200 San Cayetano-Toluca, Estado de Mexico (Mexico)

2015-07-01

The synthesis of gold nanoparticles by sonochemical technique has been previously performed with excellent results. The synthesis has been carried out in the presence of citric acid, a strong reducing agent, which allows the nucleation and growth of gold nanoparticles, at the same time that controls particle size. In this work we report the use of sodium tartrate as a mild reducing agent that allows a better understanding of the effect of the reaction parameters during gold nanoparticle synthesis. A conventional sonication bath (37 k Hz) was used for the sonochemical synthesis. This work focuses on the reaction temperature effect and the effect of sodium tartrate concentration. It was confirmed that particle size, and particle morphology is dependent of these two reaction parameters. Equally, colloidal stabilization was related to reaction temperature and sodium tartrate concentration. It was also determined that Ostwald ripening takes place during sonochemical reaction under our conditions, allowing to understand the mechanism that takes place during synthesis. Gold nanoparticles with main particle size of 17 nm were achieved by this method. Characterization techniques used: Fourier transform infrared spectra (Ftir), X-ray diffraction and Atomic Force Microscope was used in order to determine particle size of the synthetic product of reaction M10c by tapping mode. (Author)

Reaction parameters for controlled sonosynthesis of gold nanoparticles

International Nuclear Information System (INIS)

Gonzalez M, A. L.; Cabrera L, L. I.

2015-01-01

The synthesis of gold nanoparticles by sonochemical technique has been previously performed with excellent results. The synthesis has been carried out in the presence of citric acid, a strong reducing agent, which allows the nucleation and growth of gold nanoparticles, at the same time that controls particle size. In this work we report the use of sodium tartrate as a mild reducing agent that allows a better understanding of the effect of the reaction parameters during gold nanoparticle synthesis. A conventional sonication bath (37 k Hz) was used for the sonochemical synthesis. This work focuses on the reaction temperature effect and the effect of sodium tartrate concentration. It was confirmed that particle size, and particle morphology is dependent of these two reaction parameters. Equally, colloidal stabilization was related to reaction temperature and sodium tartrate concentration. It was also determined that Ostwald ripening takes place during sonochemical reaction under our conditions, allowing to understand the mechanism that takes place during synthesis. Gold nanoparticles with main particle size of 17 nm were achieved by this method. Characterization techniques used: Fourier transform infrared spectra (Ftir), X-ray diffraction and Atomic Force Microscope was used in order to determine particle size of the synthetic product of reaction M10c by tapping mode. (Author)

Comparison of techniques for the determination of conversion during suspension polymerization reactions

Directory of Open Access Journals (Sweden)

J. C. Santos

2008-06-01

Full Text Available The determination of conversion during suspension polymerization reactions is not an easy task due to the heterogeneity of the reaction medium and the tendency of particles to agglomerate rapidly when stirring is stopped. Usually, bulk polymerization in ampoules is employed to study the kinetics of suspension polymerization reactions. In this work, a comparison of different techniques for the determination of conversion during suspension polymerization reactions is presented. Results showed a good agreement between the conversion obtained by gravimetry during styrene suspension polymerization and on-line conversion monitoring data using fiber-optic based Raman Spectroscopy. Nevertheless, the polymerization rate of styrene bulk polymerization carried out in ampoules was higher than the real reaction rate of styrene suspension polymerization due to slightly higher reaction temperatures. Simulation results using the experimental temperature data in a mathematical model confirmed these results.

Population-Based Analysis of Histologically Confirmed Melanocytic Proliferations Using Natural Language Processing.

Science.gov (United States)

Lott, Jason P; Boudreau, Denise M; Barnhill, Ray L; Weinstock, Martin A; Knopp, Eleanor; Piepkorn, Michael W; Elder, David E; Knezevich, Steven R; Baer, Andrew; Tosteson, Anna N A; Elmore, Joann G

2018-01-01

Population-based information on the distribution of histologic diagnoses associated with skin biopsies is unknown. Electronic medical records (EMRs) enable automated extraction of pathology report data to improve our epidemiologic understanding of skin biopsy outcomes, specifically those of melanocytic origin. To determine population-based frequencies and distribution of histologically confirmed melanocytic lesions. A natural language processing (NLP)-based analysis of EMR pathology reports of adult patients who underwent skin biopsies at a large integrated health care delivery system in the US Pacific Northwest from January 1, 2007, through December 31, 2012. Skin biopsy procedure. The primary outcome was histopathologic diagnosis, obtained using an NLP-based system to process EMR pathology reports. We determined the percentage of diagnoses classified as melanocytic vs nonmelanocytic lesions. Diagnoses classified as melanocytic were further subclassified using the Melanocytic Pathology Assessment Tool and Hierarchy for Diagnosis (MPATH-Dx) reporting schema into the following categories: class I (nevi and other benign proliferations such as mildly dysplastic lesions typically requiring no further treatment), class II (moderately dysplastic and other low-risk lesions that may merit narrow reexcision with skin biopsies, performed on 47 529 patients, were examined. Nearly 1 in 4 skin biopsies were of melanocytic lesions (23%; n = 18 715), which were distributed according to MPATH-Dx categories as follows: class I, 83.1% (n = 15 558); class II, 8.3% (n = 1548); class III, 4.5% (n = 842); class IV, 2.2% (n = 405); and class V, 1.9% (n = 362). Approximately one-quarter of skin biopsies resulted in diagnoses of melanocytic proliferations. These data provide the first population-based estimates across the spectrum of melanocytic lesions ranging from benign through dysplastic to malignant. These results may serve as a foundation for future

Sarcoidal granulomatous reaction due to tattoos: report of two cases*

Science.gov (United States)

Valbuena, Martha Cecilia; Franco, Victoria Eugenia; Sánchez, Lorena; Jiménez, Héctor David

2017-01-01

Numerous infectious, inflammatory and neoplastic complications secondary to tattoo placement have been reported in the literature. Within inflammatory complications sarcoidal granulomatous reactions have been described. We report two cases, a 55-year-old woman with yellowish infiltrated plaques on bilateral ciliary region, 16 years after the placement of a permanent tattoo in the eyebrows, and a 20-year-old tattoo artist who developed orange papules on 3 of his tattoos. Histopathology in both cases confirmed diagnosis of sarcoidal granulomatous reaction due to tattoo pigment. PMID:29267473

Sarcoidal granulomatous reaction due to tattoos: report of two cases.

Science.gov (United States)

Valbuena, Martha Cecilia; Franco, Victoria Eugenia; Sánchez, Lorena; Jiménez, Héctor David

2017-01-01

Numerous infectious, inflammatory and neoplastic complications secondary to tattoo placement have been reported in the literature. Within inflammatory complications sarcoidal granulomatous reactions have been described. We report two cases, a 55-year-old woman with yellowish infiltrated plaques on bilateral ciliary region, 16 years after the placement of a permanent tattoo in the eyebrows, and a 20-year-old tattoo artist who developed orange papules on 3 of his tattoos. Histopathology in both cases confirmed diagnosis of sarcoidal granulomatous reaction due to tattoo pigment.

Studies of heavy-ion reactions and transuranic nuclei

International Nuclear Information System (INIS)

Schroeder, W.U.; Huizenga, J.R.

1991-08-01

The development of the ''cold-fusion'' episode is reviewed. Ongoing studies of compound-nucleus formation and decay via the neutron multiplicity distribution confirm the validity of conventional statistical theory. The excitation energy partition in near-barrier damped 58 Ni + 208 Pb collisions is found to be largely independent of the direction of net mass transfer, supporting a diffusion-like nucleon-exchange mechanism. Exclusive experiments on the heavy reaction systems 197 Au + 208 Pb and 209 Bi + 136 Xe in the Fermi-energy domain have revealed important new insights into the reaction mechanism, which is found to be dominated by damped, binary processes. The effectiveness of the neutron multiplicity as an impact-parameter filter is demonstrated. It is shown that very-heavy-ion reactions lead to transient nuclear systems with temperatures in excess of τ = 6 MeV and transfer of large, aligned spins to reaction fragments. The first measurements of neutrons in coincidence with kinematically identified reaction fragments provide evidence for the binary, sequential character of dissipative collisions in the Fermi-energy domain. Also for the first time, a full event characterization was achieved for nuclear reactions in terms of neutrons and charged particles. Technical information on this experiment is provided. First results yield strong evidence for dominantly binary primary reaction dynamics of even highly dissipative 209 Bi + (28MeV/u) 136 Xe collisions, associated with several intermediate-mass fragments

Meta-analysis identifies 29 additional ulcerative colitis risk loci, increasing the number of confirmed associations to 47

DEFF Research Database (Denmark)

Anderson, Carl A; Boucher, Gabrielle; Lees, Charlie W

2011-01-01

Genome-wide association studies and candidate gene studies in ulcerative colitis have identified 18 susceptibility loci. We conducted a meta-analysis of six ulcerative colitis genome-wide association study datasets, comprising 6,687 cases and 19,718 controls, and followed up the top association...... signals in 9,628 cases and 12,917 controls. We identified 29 additional risk loci (P associated loci to 47. After annotating associated regions using GRAIL, expression quantitative trait loci data and correlations with non-synonymous SNPs, we...... identified many candidate genes that provide potentially important insights into disease pathogenesis, including IL1R2, IL8RA-IL8RB, IL7R, IL12B, DAP, PRDM1, JAK2, IRF5, GNA12 and LSP1. The total number of confirmed inflammatory bowel disease risk loci is now 99, including a minimum of 28 shared association...

[Disappearance of residual disease confirmed by RT-PCR following induction chemotherapy in two hypoplastic leukemia patients with t(8;21)].

Science.gov (United States)

Sawada, M; Tsurumi, H; Yamada, T; Hara, T; Oyama, M; Moriwaki, H

1999-04-01

Reverse transcriptase-polymerase chain reaction (RT-PCR) methods often detect the AML1/MTG8 fusion transcript even in acute myelogenous leukemia (AML) patients with t(8;21) who have been in long-term remission. We encountered 2 hypoplastic leukemia patients with t(8;21) who achieved cytogenetic remission with short-term conventional chemotherapy. Patient 1 was a 42-year-old woman. Chromosomal analysis detected t(8;21) (q22;q22) and PCR analysis (35 cycles PCR amplification; detection limit 1 x 10(-5) cells) detected the AML1/MTG8 fusion transcript. Complete remission was obtained with 1 course of chemotherapy consisting of low-dose cytarabine (20 mg x 14 days) and etoposide (50 mg x 14 days). After 2 courses of consolidation chemotherapy consisting of conventional-dose cytarabine and mitoxantrone, the RT-PCR findings were negative for the AML1/MTG8 fusion transcript. Patient 2 was a 67-year-old man. Cytogenetic analysis detected t(8;21) (q22;q22), and was positive for the AML1/MTG8 fusion transcript. After 2 courses of induction chemotherapy comprising low-dose cytarabine (20 mg x 14 days) and etoposide (50 mg x 14 days), and 3 courses of conventional consolidation chemotherapy, RT-PCR analysis confirmed the disappearance of the AML1/MTG8 fusion transcript.

Polymerase chain reaction amplification and cloning of immunogenic protein NAD-dependent beta hydroxybutyryl CoA dehydrogenase gene of Clostridium chauvoei

Directory of Open Access Journals (Sweden)

Saroj K. Dangi

2014-10-01

Full Text Available Aim: The present study was aimed at polymerase chain reaction (PCR amplification and cloning of NAD-dependent betahydroxybutyryl coenzyme A dehydrogenase (BHBD gene of Clostridium chauvoei. Materials and Methods: C. chauvoei was cultured and confirmed by 16-23S rDNA spacer region primers. The primers for nad-bhbd gene of C. chauvoei were designed to aid in cloning into pRham-N-His SUMO-Kan vector, and nad-bhbd gene was amplified by PCR. The amplified nad-bhbd gene was purified and cloned into pRham-N-His SUMO-Kan expression vector. The recombinant plasmid was transformed into E. cloni 10 G cells and the clone was confirmed by colony PCR using the pRham-SUMO-NAD-For and pRham-SUMO-NAD-Rev primers and also by sequencing. Results: PCR amplification of nad-bhbd gene yielded a product length of 844 base pairs which was cloned into pRham-NHis SUMO-Kan vector followed by transformation into E. cloni 10G chemically competent cells. The recombinant clones were characterized by colony PCR, sequencing, followed by basic local alignment search tool (BLAST analysis to confirm the insert. Conclusions: Immunogenic protein NAD- dependent BHBD of C. chauvoei was cloned and the recombinant clones were confirmed by colony PCR and sequencing analysis.

FY 1998 report on the result of R and D projects by local consortiums. Rare metal recovery and resourcing of residual slags from metal plating wastes and aluminum dross by continuous thermit reaction (CTR) system; 1998 nendo CTR (Continuous Termit Reaction) System ni yoru aluminium dross to mekki surajji kara no energy less, rare metal kaisei process to sono slag no saishigenka seika hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-03-01

The R and D project has been implemented for treating metal plating wastes (sludge) and aluminum dross in a melting furnace operated in a reducing atmosphere, in order to make the wastes harmless and recover the rare metals by the thermit reactions. The theoretical analysis of the powder properties has produced the desired powder pretreatment conditions, such as drying/firing conditions, mixing ratio and composition, forming conditions, and characteristics of the formed articles. For recovering the useful metals, it is confirmed that the thermit reactions proceed efficiently in a high-temperature melting furnace operated in a reducing atmosphere, and the molten metals are easily separated from the molten slag. It is also confirmed that the formed article allows separation of the metals from the residual slag more easily than the mixed powder. For the design of the continuous thermit reaction (CTR) system, it is investigated whether the products and other discharged substances can be safely handled and effectively utilized, and the control/instrumentation systems and others are established after setting the conditions for, e.g., sludge drying/firing in air, powder mixing/crushing, briquette production, and flow of the thermit reactions in a reducing atmosphere. (NEDO)

On the rejection-based algorithm for simulation and analysis of large-scale reaction networks

Energy Technology Data Exchange (ETDEWEB)

Thanh, Vo Hong, E-mail: vo@cosbi.eu [The Microsoft Research-University of Trento Centre for Computational and Systems Biology, Piazza Manifattura 1, Rovereto 38068 (Italy); Zunino, Roberto, E-mail: roberto.zunino@unitn.it [Department of Mathematics, University of Trento, Trento (Italy); Priami, Corrado, E-mail: priami@cosbi.eu [The Microsoft Research-University of Trento Centre for Computational and Systems Biology, Piazza Manifattura 1, Rovereto 38068 (Italy); Department of Mathematics, University of Trento, Trento (Italy)

2015-06-28

Stochastic simulation for in silico studies of large biochemical networks requires a great amount of computational time. We recently proposed a new exact simulation algorithm, called the rejection-based stochastic simulation algorithm (RSSA) [Thanh et al., J. Chem. Phys. 141(13), 134116 (2014)], to improve simulation performance by postponing and collapsing as much as possible the propensity updates. In this paper, we analyze the performance of this algorithm in detail, and improve it for simulating large-scale biochemical reaction networks. We also present a new algorithm, called simultaneous RSSA (SRSSA), which generates many independent trajectories simultaneously for the analysis of the biochemical behavior. SRSSA improves simulation performance by utilizing a single data structure across simulations to select reaction firings and forming trajectories. The memory requirement for building and storing the data structure is thus independent of the number of trajectories. The updating of the data structure when needed is performed collectively in a single operation across the simulations. The trajectories generated by SRSSA are exact and independent of each other by exploiting the rejection-based mechanism. We test our new improvement on real biological systems with a wide range of reaction networks to demonstrate its applicability and efficiency.

Severe reactions to iodinated contrast agents: is anaphylaxis responsible?

International Nuclear Information System (INIS)

Dewachter, P.; Mouton-Faivre, C.

2001-01-01

The etiology of severe reactions following injection of iodinated contrast agent is the subject of controversy. No consensus has been established regarding the management of patients at risk, risk factors and pre-medication because in most cases published no diagnostic exploration has been carried out on patients who have experienced a severe reaction. Diagnosis of drug anaphylaxis is based on clinical history, proof of mediator release and drug specific IgE antibodies (when the technique is available) or cutaneous tests (when direct technique is not available). This approach has been adopted for etiologic diagnosis of 5 clinical cases of severe anaphylactoid reactions (including one death) following the injection of ionic and non ionic contrast agents. Clinical symptoms, biology and cutaneous tests are consistent with anaphylaxis. Any patient who has had a severe anaphylactoid reaction following injection of a contrast agent should undergo an allergology assessment to confirm the diagnosis and identify the culprit contrast agent. Indeed, no pre-medication has proved efficient for the prevention of subsequent allergic reactions. (author)

Partial wave analysis of KKPI system in D and E/IOTA region

International Nuclear Information System (INIS)

Chung, S.U.; Fernow, R.; Kirk, H.

1985-01-01

A partial wave analysis and a Dalitz plot analysis of high-statistics data from reaction π - p → K + K/sub S/π - n at 8.0 GeV/c show that the D(1285) is a J/sup PG/ = 1 ++ state and the E(1420) a J/sup PG/ = 0 -+ state both with a substantial deltaπ decay mode. The 1 ++ K*anti K wave exhibits a rapid rise near threshold but no evidence of a resonance in the E region. The assignment of J/sup PG/ = O -+ to the E is confirmed from a Dalitz-plot analysis of the reaction pp → K + K/sub S/π - X 0 . 11 refs., 5 figs

Passivity analysis for uncertain BAM neural networks with time delays and reaction-diffusions

Science.gov (United States)

Zhou, Jianping; Xu, Shengyuan; Shen, Hao; Zhang, Baoyong

2013-08-01

This article deals with the problem of passivity analysis for delayed reaction-diffusion bidirectional associative memory (BAM) neural networks with weight uncertainties. By using a new integral inequality, we first present a passivity condition for the nominal networks, and then extend the result to the case with linear fractional weight uncertainties. The proposed conditions are expressed in terms of linear matrix inequalities, and thus can be checked easily. Examples are provided to demonstrate the effectiveness of the proposed results.

Kinetics of the high temperature oxygen exchange reaction on {sup 238}PuO{sub 2} powder

Energy Technology Data Exchange (ETDEWEB)

Whiting, Christofer E., E-mail: chris.whiting@udri.udayton.edu [University of Dayton – Research Institute, 300 College Park, Dayton, OH 45469-0172 (United States); Du, Miting; Felker, L. Kevin; Wham, Robert M. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831 (United States); Barklay, Chadwick D.; Kramer, Daniel P. [University of Dayton – Research Institute, 300 College Park, Dayton, OH 45469-0172 (United States)

2015-12-15

Oxygen exchange reactions performed on PuO{sub 2} suggest the reaction is influenced by at least three mechanisms: an internal chemical reaction, surface mobility of active species/defects, and surface exchange of gaseous oxygen with lattice oxygen. Activation energies for the surface mobility and internal chemical reaction are presented. Determining which mechanism is dominant appears to be a complex function including at least specific surface area and temperature. Thermal exposure may also impact the oxygen exchange reaction by causing reductions in the specific surface area of PuO{sub 2}. Previous CeO{sub 2} surrogate studies exhibit similar behavior, confirming that CeO{sub 2} is a good qualitative surrogate for PuO{sub 2}, in regards to the oxygen exchange reaction. Comparison of results presented here with previous work on the PuO{sub 2} oxygen exchange reaction allows complexities in the previous work to be explained. These explanations allowed new conclusions to be drawn, many of which confirm the conclusions presented here. - Highlights: • PuO{sub 2} Oxygen exchange kinetics can be influenced by at least 3 different mechanisms. • An internal chemical reaction controls the rate at high temperature and large SSA. • Surface mobility and surface exchange influence rate at lower temperatures and SSA. • Exchange temperatures may alter SSA and make data difficult to interpret.

Possibility of analysis using RBS, PIXE and nuclear reaction on the electrostatic Pelletron accelerator 5SDH-2

International Nuclear Information System (INIS)

Nguyen The Nghia; Bui Van Loat; Le Hong Khiem

2011-01-01

The electrostatic Pelletron accelerator 5SDH-2 is installing at Hanoi University of Sciences. This accelerator will be the first tandem electrostatic accelerator installed in Vietnam. The schematic structure, principle of operation of the machine and its application for analysis using Rutherford Back Scattering (RBS), Particle-Induced X-ray Emission (PIXE) and Nuclear Reaction Analysis (NRA) will be presented. (author)

Analysis of charged particle induced reactions for beam monitor applications

Energy Technology Data Exchange (ETDEWEB)

Surendra Babu, K. [IOP, Academia Sinica, Taipe, Taiwan (China); Lee, Young-Ouk [Nuclear Data Evaluation Laboratory, Korea Atomic Energy Research Institute (Korea, Republic of); Mukherjee, S., E-mail: smukherjee_msuphy@yahoo.co.in [Department of Physics, Faculty of Science, M.S. University of Baroda, Vadodara 390 002 (India)

2012-07-15

The reaction cross sections for different residual nuclides produced in the charged particle (p, d, {sup 3}He and {alpha}) induced reactions were calculated and compared with the existing experimental data which are important for beam monitoring and medical diagnostic applications. A detailed literature compilation and comparison were made on the available data sets for the above reactions. These calculations were carried out using the statistical model code TALYS up to 100 MeV, which contains Kalbach's latest systematic for the emission of complex particles and complex particle-induced reactions. All optical model calculations were performed by ECIS-03, which is built into TALYS. The level density, optical model potential parameters were adjusted to get the better description of experimental data. Various pre-equilibrium models were used in the present calculations with default parameters.

The Reaction Mechanism and Rate Constants in the Radiolysis of Fe2+-Cu2+ Solutions

DEFF Research Database (Denmark)

Bjergbakke, Erling; Sehested, Knud; Rasmussen, O. Lang

1976-01-01

Pulse radiolysis and gamma radiolysis have been used to study the reaction mechanism in the radiolysis of aqueous solutions of Fe2+ and Cu2+. A reaction scheme has been developed and confirmed by computation of the corresponding complete set of differential equations. The rate constants for some ...... 10^{8}$ and $1.3\\times 10^{8}\\ {\\rm mol}^{-1}\\ {\\rm sec}^{-1}$ in pH 2.1 H2 SO4 and HClO4, respectively.......Pulse radiolysis and gamma radiolysis have been used to study the reaction mechanism in the radiolysis of aqueous solutions of Fe2+ and Cu2+. A reaction scheme has been developed and confirmed by computation of the corresponding complete set of differential equations. The rate constants for some...... of the reactions have been determined at different pH's. $k_{{\\rm Cu}^{+}+{\\rm O}_{2}}=4.6\\times 10^{5}$ and $1.0\\times 10^{6}\\ {\\rm mol}^{-1}\\ {\\rm sec}^{-1}$, $k_{{\\rm Cu}^{+}+{\\rm Fe}^{3+}}=5.5\\times 10^{6}$ and $1.3\\times 10^{7}\\ {\\rm mol}^{-1}\\ {\\rm sec}^{-1}$, $k_{{\\rm Cu}({\\rm III)}+{\\rm Fe}^{2+}}=3.3\\times...

Induction and Confirmation Theory: An Approach based on a Paraconsistent Nonmonotonic Logic

Directory of Open Access Journals (Sweden)

Ricardo Sousa Silvestre

2011-05-01

Full Text Available This paper is an effort to realize and explore the connections that exist between nonmonotonic logic and confirmation theory. We pick up one of the most wide-spread nonmonotonic formalisms – default logic – and analyze to what extent and under what adjustments it could work as a logic of induction in the philosophical sense. By making use of this analysis, we extend default logic so as to make it able to minimally perform the task of a logic of induction, having as a result a system which we believe has interesting properties from the standpoint of theory of confirmation. It is for instance able to represent chains of inductive rules as well as to reason paraconsistently on the conclusions obtained from them. We then use this logic to represent some traditional ideas concerning confirmation theory, in particular the ones proposed by Carl Hempel in his classical paper "Studies in the Logic of Confirmation" of 1945 and the ones incorporated in the so-called abductive and hy-pothetico-deductive models.

Reformulation and solution of the master equation for multiple-well chemical reactions.

Science.gov (United States)

Georgievskii, Yuri; Miller, James A; Burke, Michael P; Klippenstein, Stephen J

2013-11-21

We consider an alternative formulation of the master equation for complex-forming chemical reactions with multiple wells and bimolecular products. Within this formulation the dynamical phase space consists of only the microscopic populations of the various isomers making up the reactive complex, while the bimolecular reactants and products are treated equally as sources and sinks. This reformulation yields compact expressions for the phenomenological rate coefficients describing all chemical processes, i.e., internal isomerization reactions, bimolecular-to-bimolecular reactions, isomer-to-bimolecular reactions, and bimolecular-to-isomer reactions. The applicability of the detailed balance condition is discussed and confirmed. We also consider the situation where some of the chemical eigenvalues approach the energy relaxation time scale and show how to modify the phenomenological rate coefficients so that they retain their validity.

Parallel replica dynamics method for bistable stochastic reaction networks: Simulation and sensitivity analysis

Science.gov (United States)

Wang, Ting; Plecháč, Petr

2017-12-01

Stochastic reaction networks that exhibit bistable behavior are common in systems biology, materials science, and catalysis. Sampling of stationary distributions is crucial for understanding and characterizing the long-time dynamics of bistable stochastic dynamical systems. However, simulations are often hindered by the insufficient sampling of rare transitions between the two metastable regions. In this paper, we apply the parallel replica method for a continuous time Markov chain in order to improve sampling of the stationary distribution in bistable stochastic reaction networks. The proposed method uses parallel computing to accelerate the sampling of rare transitions. Furthermore, it can be combined with the path-space information bounds for parametric sensitivity analysis. With the proposed methodology, we study three bistable biological networks: the Schlögl model, the genetic switch network, and the enzymatic futile cycle network. We demonstrate the algorithmic speedup achieved in these numerical benchmarks. More significant acceleration is expected when multi-core or graphics processing unit computer architectures and programming tools such as CUDA are employed.

Parallel replica dynamics method for bistable stochastic reaction networks: Simulation and sensitivity analysis.

Science.gov (United States)

Wang, Ting; Plecháč, Petr

2017-12-21

Stochastic reaction networks that exhibit bistable behavior are common in systems biology, materials science, and catalysis. Sampling of stationary distributions is crucial for understanding and characterizing the long-time dynamics of bistable stochastic dynamical systems. However, simulations are often hindered by the insufficient sampling of rare transitions between the two metastable regions. In this paper, we apply the parallel replica method for a continuous time Markov chain in order to improve sampling of the stationary distribution in bistable stochastic reaction networks. The proposed method uses parallel computing to accelerate the sampling of rare transitions. Furthermore, it can be combined with the path-space information bounds for parametric sensitivity analysis. With the proposed methodology, we study three bistable biological networks: the Schlögl model, the genetic switch network, and the enzymatic futile cycle network. We demonstrate the algorithmic speedup achieved in these numerical benchmarks. More significant acceleration is expected when multi-core or graphics processing unit computer architectures and programming tools such as CUDA are employed.

Measurement and analysis of cross sections for (p,x) reactions on natural molybdenum

International Nuclear Information System (INIS)

Challan, M. B.; Comsan, M.N.H.; Abou-Zeid, M.A.

2006-01-01

Excitation functions (EFs) for the reactions n atMo(p,x) 92m Nb, and n atMo(p,x) 94 , 95m , 95g , 96 m, +g , 99m Tc up to 18 MeV from threshold have been measured employing the stacked foil activation technique, and using high resolution HPGe gamma spectrometry. Utilizing the simultaneous measurement of the excitation function of n atCu(p,x) 62 Zn, n atCu(p,x) 63 Zn, n atCu(p,x) 65 Zn, and n atTi(p,x) 48 V monitor reactions. The theoretical analysis of the EFs has been done using both the semi-classical as well as quantum mechanical codes which include compound nucleus and pre-equilibrium (PE) emission into consideration. In general, theoretical calculations agree well with the experimental data. Effect of various free parameters used in the calculations has also been discussed. A significant contribution of pre-equilibrium component has been observed at these energies

Analysis and protease-catalysed synthesis of sucrose alkanoate regioisomers

DEFF Research Database (Denmark)

Lie, Aleksander

2014-01-01

The aims of the presented research were to develop quantifiable methods for reversed-phase high-performance liquid chromatography analysis of sucrose alkanoate regioisomers and to investigate the activity and regioisomeric distribution in the biocatalytic esterification of sucrose with vinyl laur...... in the reaction mixture appeared to be catalysed by the presence of aluminosilicate molecular sieves in the reaction medium. Mass spectrometry analysis of sucrose laurate product confirmed the molecular mass.......The aims of the presented research were to develop quantifiable methods for reversed-phase high-performance liquid chromatography analysis of sucrose alkanoate regioisomers and to investigate the activity and regioisomeric distribution in the biocatalytic esterification of sucrose with vinyl...... laurate in DMF using serine proteases and a metalloprotease. A broad range of elution strategies for the chromatographic analysis of sucrose alkanoate regioisomers was systematically investigated using design of experiments strategies and statistical and multivariate analysis and modelling. Efficiency...

Investigation of Na-CO{sub 2} Reaction with Initial Reaction in Various Reacting Surface

Energy Technology Data Exchange (ETDEWEB)

Kim, Hyun Su; Park, Gunyeop; Kim, Soo Jae; Park, Hyun Sun; Kim, Moo Hwan [POSTECH, Pohang (Korea, Republic of); Wi, Myung-Hwan [KAERI, Daejeon (Korea, Republic of)

2015-10-15

The reaction products that cause oxidation and erosion are threaten the heat transfer tubes so that it is necessary to investigate Na-CO{sub 2} reaction according to various experimental parameter. Unlike SWR, Na-CO{sub 2} reaction is more complex to deal with reaction kinetics. Since a comprehensive understanding of Na-CO{sub 2} reaction mechanism is crucial for the safety analysis, the reaction phenomenon under the various conditions was investigated. The current issue is to make a database for developing computational code for CO{sub 2} gas leak situation because it is experimentally difficult to analyze the actual accident situation. Most studies on Na-CO{sub 2} interaction reports that chemical reaction is getting vigorous as temperature increased and reactivity is sensitive as temperature change between 400 .deg. C and 600 .deg. C. Therefore, temperature range is determined based on the operating condition (450 - 500 .deg. C) of KALIMER-600 employed as supercritical CO{sub 2} brayton cycle energy conversion system for Na-CO{sub 2} heat exchanger. And next parameter is sodium surface area which contact between sodium and CO{sub 2} when CO{sub 2} is injected into sodium pool in the accident situation. So, the fundamental surface reaction is experimentally studied in the range of 8 - 12cm{sup 2}. Additionally, it has been reported in recent years that CO{sub 2} Flow rate affects reactivity less significantly and CO{sub 2} flow rate is assumed that 5 SLPM (standard liter per minute) is suitable as a basis for a small leakage. The finally selected control parameters is sodium temperature and reacting surface area with constant CO{sub 2} flow rate. Na-CO{sub 2} reaction test is performed for investigating risk of potential accident which contacts with liquid sodium and CO{sub 2}. Amount of reaction is saturated as time passed because of kept a balance between production of solid phase reaction products and amount of diffusivity. These results contribute to make a

The analysis of magnesium oxide hydration in three-phase reaction system

Energy Technology Data Exchange (ETDEWEB)

Tang, Xiaojia; Guo, Lin; Chen, Chen; Liu, Quan; Li, Tie; Zhu, Yimin, E-mail: ntp@dlmu.edu.cn

2014-05-01

In order to investigate the magnesium oxide hydration process in gas–liquid–solid (three-phase) reaction system, magnesium hydroxide was prepared by magnesium oxide hydration in liquid–solid (two-phase) and three-phase reaction systems. A semi-empirical model and the classical shrinking core model were used to fit the experimental data. The fitting result shows that both models describe well the hydration process of three-phase system, while only the semi-empirical model right for the hydration process of two-phase system. The characterization of the hydration product using X-Ray diffraction (XRD) and scanning electron microscope (SEM) was performed. The XRD and SEM show hydration process in the two-phase system follows common dissolution/precipitation mechanism. While in the three-phase system, the hydration process undergo MgO dissolution, Mg(OH){sub 2} precipitation, Mg(OH){sub 2} peeling off from MgO particle and leaving behind fresh MgO surface. - Graphical abstract: There was existence of a peeling-off process in the gas–liquid–solid (three-phase) MgO hydration system. - Highlights: • Magnesium oxide hydration in gas–liquid–solid system was investigated. • The experimental data in three-phase system could be fitted well by two models. • The morphology analysis suggested that there was existence of a peel-off process.

Generalized eczematous reaction after fractional carbon dioxide laser therapy for tattoo allergy.

Science.gov (United States)

Meesters, Arne A; De Rie, Menno A; Wolkerstorfer, Albert

2016-12-01

Allergic tattoo reactions form a therapeutically difficult entity. Treatment with conventional quality-switched lasers does not completely remove the allergenic particles and may lead to generalized hypersensitivity reactions. Recently, ablative fractional laser therapy was introduced as a treatment for allergic tattoo removal. We present two cases of allergic reactions to red tattoo ink treated with 10,600-nm fractional CO 2 laser. At the end of treatment, almost complete removal of red ink accompanied by a significant reduction of symptoms was observed in the first patient, whereas the second patient developed an acute generalized eczematous reaction after five treatments. These findings confirm that ablative fractional laser therapy is capable of significant removal of tattoo ink in an allergic tattoo reaction. However, it implies a risk of generalized hypersensitivity reactions. To our knowledge, this is the first case of a generalized hypersensitivity reaction following treatment of tattoo allergy with the fractional CO 2 laser.

Insights into the mechanisms on chemical reactions: reaction paths for chemical reactions

International Nuclear Information System (INIS)

Dunning, T.H. Jr.; Rosen, E.; Eades, R.A.

1987-01-01

We report reaction paths for two prototypical chemical reactions: Li + HF, an electron transfer reaction, and OH + H 2 , an abstraction reaction. In the first reaction we consider the connection between the energetic terms in the reaction path Hamiltonian and the electronic changes which occur upon reaction. In the second reaction we consider the treatment of vibrational effects in chemical reactions in the reaction path formalism. 30 refs., 9 figs

Investigation of structural properties associated with alkali-silica reaction by means of macro- and micro-structural analysis

International Nuclear Information System (INIS)

Mo Xiangyin; Fournier, Benoit

2007-01-01

Structural properties associated with alkali-silica reaction were systematically investigated by means of macro-structural accelerated mortar prism expansion levels testing, combined with micro-structural analysis. One part of this study is to determine the reactivity of the aggregate by means of accelerated mortar bar tests, and also to evaluate perlite aggregate constituents, especially the presence of deleterious components and find main causes of the alkali-silica reaction, which was based on the petrographic studies by optical microscope and the implication of X-ray diffraction on the aggregate. Results implied that the aggregate was highly alkali-silica reactive and the main micro-crystalline quartz-intermediate character and matrix that is mainly composed of chalcedony are potentially suitable for alkali-silica reaction. The other part is to study the long-term effect of lithium salts against alkali-silica reaction by testing accelerated mortar prism expansion levels. The macro-structural results were also consistent with the micro-structural mechanisms of alkali-silica reaction of mortar prisms containing this aggregate and the effect of chemical admixtures by means of the methods of scanning electron microscope-X-ray energy-dispersive spectroscopy and X-ray diffraction. It was indicated by these techniques that lithium salts, which were introduced into concrete containing reactive aggregate at the mixing stage, suppressed the alkali-silica reaction by producing non-expansive crystalline materials

The thermospheric auroral red line polarization: confirmation of detection and first quantitative analysis

Directory of Open Access Journals (Sweden)

Moen Joran

2013-01-01

Full Text Available The thermospheric atomic oxygen red line is among the brightest in the auroral spectrum. Previous observations in Longyearbyen, Svalbard, indicated that it may be intrinsically polarized, but a possible contamination by light pollution could not be ruled out. During the winter 2010/2011, the polarization of the red line was measured for the first time at the Polish Hornsund polar base without contamination. Two methods of data analysis are presented to compute the degree of linear polarization (DoLP and angle of linear polarization (AoLP: one is based on averaging and the other one on filtering. Results are compared and are in qualitative agreement. For solar zenith angles (SZA larger than 108° (with no contribution from Rayleigh scattering, the DoLP ranges between 2 and 7%. The AoLP is more or less aligned with the direction of the magnetic field line, in agreement with the theoretical predictions of Bommier et al. (2010. However, the AoLP values range between ±20° around this direction, depending on the auroral conditions. Correlations between the polarization parameters and the red line intensity I were considered. The DoLP decreases when I increases, confirming a trend observed during the observations in Longyearbyen. However, for small values of I, DoLP varies within a large range of values, while for large values of I, DoLP is always small. The AoLP also varies with the red line intensity, slightly rotating around the magnetic field line.

CERN confirms LHC schedule

CERN Document Server

2003-01-01

The CERN Council held its 125th session on 20 June. Highlights of the meeting included confirmation that the LHC is on schedule for a 2007 start-up, and the announcement of a new organizational structure in 2004.

Public reactions in Norway to radioactive fallout

International Nuclear Information System (INIS)

Weisaeth, L.; Toennessen, A.

1995-01-01

Surveys carried out on representative samples of the adult Norwegian population in May/June 1986 and June 1993 have shed light on psychological responses to the Chernobyl disaster from a distant population. The data from 1986 confirm the impression from the first weeks following the disaster of an information crisis with a public discontented with the information and guidance provided by the authorities. Sex, age, educational level, general threat perception and previous mental health were factors associated with information and reaction variables and may help to identify groups with characteristic response patterns. A consistent finding has been the stronger reactions in women. The development from 1986 to 1993 is discussed: the findings are discussed in the context of a coping model for dealing with stressful events. (Author)

The measurements of parity violation in resonant neutron-capture reactions

International Nuclear Information System (INIS)

Sharapov, E.I.; Popov, Y.P.; Wender, S.A.; Seestrom, S.J.; Bowman, C.D.; Postma, H.; Gould, C.R.; Wasson, A.

1990-01-01

The study of parity violation in total (n,γ) cross sections on 139 La and 117 Sn targets was performed at the LANSCE pulsed neutron source using longitudinally polarized neutrons and a BaF 2 detector. The effect of parity nonconservation in the 139 La(n,γ) reaction for the resonance at E n =0.73 eV was confirmed. New results for p-wave resonances in the 117 Sn(n, γ) reaction were obtained. A comparison between the capture and transmission techniques is presented. 12 refs., 5 figs., 1 tab

Accelerated Sensitivity Analysis in High-Dimensional Stochastic Reaction Networks.

Science.gov (United States)

Arampatzis, Georgios; Katsoulakis, Markos A; Pantazis, Yannis

2015-01-01

Existing sensitivity analysis approaches are not able to handle efficiently stochastic reaction networks with a large number of parameters and species, which are typical in the modeling and simulation of complex biochemical phenomena. In this paper, a two-step strategy for parametric sensitivity analysis for such systems is proposed, exploiting advantages and synergies between two recently proposed sensitivity analysis methodologies for stochastic dynamics. The first method performs sensitivity analysis of the stochastic dynamics by means of the Fisher Information Matrix on the underlying distribution of the trajectories; the second method is a reduced-variance, finite-difference, gradient-type sensitivity approach relying on stochastic coupling techniques for variance reduction. Here we demonstrate that these two methods can be combined and deployed together by means of a new sensitivity bound which incorporates the variance of the quantity of interest as well as the Fisher Information Matrix estimated from the first method. The first step of the proposed strategy labels sensitivities using the bound and screens out the insensitive parameters in a controlled manner. In the second step of the proposed strategy, a finite-difference method is applied only for the sensitivity estimation of the (potentially) sensitive parameters that have not been screened out in the first step. Results on an epidermal growth factor network with fifty parameters and on a protein homeostasis with eighty parameters demonstrate that the proposed strategy is able to quickly discover and discard the insensitive parameters and in the remaining potentially sensitive parameters it accurately estimates the sensitivities. The new sensitivity strategy can be several times faster than current state-of-the-art approaches that test all parameters, especially in "sloppy" systems. In particular, the computational acceleration is quantified by the ratio between the total number of parameters over the

Accelerated Sensitivity Analysis in High-Dimensional Stochastic Reaction Networks.

Directory of Open Access Journals (Sweden)

Georgios Arampatzis

Full Text Available Existing sensitivity analysis approaches are not able to handle efficiently stochastic reaction networks with a large number of parameters and species, which are typical in the modeling and simulation of complex biochemical phenomena. In this paper, a two-step strategy for parametric sensitivity analysis for such systems is proposed, exploiting advantages and synergies between two recently proposed sensitivity analysis methodologies for stochastic dynamics. The first method performs sensitivity analysis of the stochastic dynamics by means of the Fisher Information Matrix on the underlying distribution of the trajectories; the second method is a reduced-variance, finite-difference, gradient-type sensitivity approach relying on stochastic coupling techniques for variance reduction. Here we demonstrate that these two methods can be combined and deployed together by means of a new sensitivity bound which incorporates the variance of the quantity of interest as well as the Fisher Information Matrix estimated from the first method. The first step of the proposed strategy labels sensitivities using the bound and screens out the insensitive parameters in a controlled manner. In the second step of the proposed strategy, a finite-difference method is applied only for the sensitivity estimation of the (potentially sensitive parameters that have not been screened out in the first step. Results on an epidermal growth factor network with fifty parameters and on a protein homeostasis with eighty parameters demonstrate that the proposed strategy is able to quickly discover and discard the insensitive parameters and in the remaining potentially sensitive parameters it accurately estimates the sensitivities. The new sensitivity strategy can be several times faster than current state-of-the-art approaches that test all parameters, especially in "sloppy" systems. In particular, the computational acceleration is quantified by the ratio between the total number of

Nuclear reactions as structure probes

International Nuclear Information System (INIS)

Fernandez, Bernard; Cugnon, Joseph; Roussel-Chomaz, Patricia; Sparenberg, Jean-Marc; Oliveira Santos, Francois de; Bauge, Eric; Poves, Alfredo; Keeley, Nicholas; Simenel, Cedric; Avez, Benoit; Lacroix, Denis; Baye, Daniel; Cortina-Gil, Dolores; Pons, Alexandre

2007-09-01

This publication gathers courses which aim at giving a view on new experiments which are performed by using radioactive beams, notably low intensity beams, in different accelerators, and allow the structure of very exotic nuclei to be characterized. Experimental as well as theoretical aspects are thus addressed. The contributions propose: a brief history of nuclear reactions and of instruments used to study them from the discovery of nucleus to the DWBA (Distorted Wave Born Approximation); an overview of nuclear reactions; experimental techniques; the theory of collisions at low energy; resonant elastic scattering, inelastic scattering and astrophysical reactions; to probe nuclear structure with nucleons; shell model and spectroscopic factors; analysis of transfer reactions and determination of spectroscopic factors; microscopic approaches of nuclear dynamics; theoretical aspects of dissociation reactions; experimental aspects of knockout reactions; research in oenology with the chemical characterisation of defective ageing of dry white wines

Comprehensive genetic analysis of early host body reactions to the bioactive and bio-inert porous scaffolds.

Directory of Open Access Journals (Sweden)

Tomo Ehashi

Full Text Available To design scaffolds for tissue regeneration, details of the host body reaction to the scaffolds must be studied. Host body reactions have been investigated mainly by immunohistological observations for a long time. Despite of recent dramatic development in genetic analysis technologies, genetically comprehensive changes in host body reactions are hardly studied. There is no information about host body reactions that can predict successful tissue regeneration in the future. In the present study, porous polyethylene scaffolds were coated with bioactive collagen or bio-inert poly(2-methacryloyloxyethyl phosphorylcholine-co-n-butyl methacrylate (PMB and were implanted subcutaneously and compared the host body reaction to those substrates by normalizing the result using control non-coat polyethylene scaffold. The comprehensive analyses of early host body reactions to the scaffolds were carried out using a DNA microarray assay. Within numerous genes which were expressed differently among these scaffolds, particular genes related to inflammation, wound healing, and angiogenesis were focused upon. Interleukin (IL-1β and IL-10 are important cytokines in tissue responses to biomaterials because IL-1β promotes both inflammation and wound healing and IL-10 suppresses both of them. IL-1β was up-regulated in the collagen-coated scaffold. Collagen-specifically up-regulated genes contained both M1- and M2-macrophage-related genes. Marked vessel formation in the collagen-coated scaffold was occurred in accordance with the up-regulation of many angiogenesis-inducible factors. The DNA microarray assay provided global information regarding the host body reaction. Interestingly, several up-regulated genes were detected even on the very bio-inert PMB-coated surfaces and those genes include inflammation-suppressive and wound healing-suppressive IL-10, suggesting that not only active tissue response but also the inert response may relates to these genetic

Comprehensive Genetic Analysis of Early Host Body Reactions to the Bioactive and Bio-Inert Porous Scaffolds

Science.gov (United States)

Ehashi, Tomo; Takemura, Taro; Hanagata, Nobutaka; Minowa, Takashi; Kobayashi, Hisatoshi; Ishihara, Kazuhiko; Yamaoka, Tetsuji

2014-01-01

To design scaffolds for tissue regeneration, details of the host body reaction to the scaffolds must be studied. Host body reactions have been investigated mainly by immunohistological observations for a long time. Despite of recent dramatic development in genetic analysis technologies, genetically comprehensive changes in host body reactions are hardly studied. There is no information about host body reactions that can predict successful tissue regeneration in the future. In the present study, porous polyethylene scaffolds were coated with bioactive collagen or bio-inert poly(2-methacryloyloxyethyl phosphorylcholine-co-n-butyl methacrylate) (PMB) and were implanted subcutaneously and compared the host body reaction to those substrates by normalizing the result using control non-coat polyethylene scaffold. The comprehensive analyses of early host body reactions to the scaffolds were carried out using a DNA microarray assay. Within numerous genes which were expressed differently among these scaffolds, particular genes related to inflammation, wound healing, and angiogenesis were focused upon. Interleukin (IL)-1β and IL-10 are important cytokines in tissue responses to biomaterials because IL-1β promotes both inflammation and wound healing and IL-10 suppresses both of them. IL-1β was up-regulated in the collagen-coated scaffold. Collagen-specifically up-regulated genes contained both M1- and M2-macrophage-related genes. Marked vessel formation in the collagen-coated scaffold was occurred in accordance with the up-regulation of many angiogenesis-inducible factors. The DNA microarray assay provided global information regarding the host body reaction. Interestingly, several up-regulated genes were detected even on the very bio-inert PMB-coated surfaces and those genes include inflammation-suppressive and wound healing-suppressive IL-10, suggesting that not only active tissue response but also the inert response may relates to these genetic regulations. PMID:24454803

Complement activation in leprosy: a retrospective study shows elevated circulating terminal complement complex in reactional leprosy.

Science.gov (United States)

Bahia El Idrissi, N; Hakobyan, S; Ramaglia, V; Geluk, A; Morgan, B Paul; Das, P Kumar; Baas, F

2016-06-01

Mycobacterium leprae infection gives rise to the immunologically and histopathologically classified spectrum of leprosy. At present, several tools for the stratification of patients are based on acquired immunity markers. However, the role of innate immunity, particularly the complement system, is largely unexplored. The present retrospective study was undertaken to explore whether the systemic levels of complement activation components and regulators can stratify leprosy patients, particularly in reference to the reactional state of the disease. Serum samples from two cohorts were analysed. The cohort from Bangladesh included multi-bacillary (MB) patients with (n = 12) or without (n = 46) reaction (R) at intake and endemic controls (n = 20). The cohort from Ethiopia included pauci-bacillary (PB) (n = 7) and MB (n = 23) patients without reaction and MB (n = 15) patients with reaction. The results showed that the activation products terminal complement complex (TCC) (P ≤ 0·01), C4d (P ≤ 0·05) and iC3b (P ≤ 0·05) were specifically elevated in Bangladeshi patients with reaction at intake compared to endemic controls. In addition, levels of the regulator clusterin (P ≤ 0·001 without R; P < 0·05 with R) were also elevated in MB patients, irrespective of a reaction. Similar analysis of the Ethiopian cohort confirmed that, irrespective of a reaction, serum TCC levels were increased significantly in patients with reactions compared to patients without reactions (P ≤ 0·05). Our findings suggests that serum TCC levels may prove to be a valuable tool in diagnosing patients at risk of developing reactions. © 2016 British Society for Immunology.

Automatic simplification of systems of reaction-diffusion equations by a posteriori analysis.

Science.gov (United States)

Maybank, Philip J; Whiteley, Jonathan P

2014-02-01

Many mathematical models in biology and physiology are represented by systems of nonlinear differential equations. In recent years these models have become increasingly complex in order to explain the enormous volume of data now available. A key role of modellers is to determine which components of the model have the greatest effect on a given observed behaviour. An approach for automatically fulfilling this role, based on a posteriori analysis, has recently been developed for nonlinear initial value ordinary differential equations [J.P. Whiteley, Model reduction using a posteriori analysis, Math. Biosci. 225 (2010) 44-52]. In this paper we extend this model reduction technique for application to both steady-state and time-dependent nonlinear reaction-diffusion systems. Exemplar problems drawn from biology are used to demonstrate the applicability of the technique. Copyright © 2014 Elsevier Inc. All rights reserved.

Reactions of uranium hexafluoride photolysis products

Science.gov (United States)

Lyman, John L.; Laguna, Glenn; Greiner, N. R.

1985-01-01

This paper confirms that the ultraviolet photolysis reactions of UF6 in the B band spectral region is simple bond cleavage to UF5 and F. The photolysis products may either recombine to UF6 or the UF5 may dimerize, and ultimately polymerize, to solid UF5 particles. We use four methods to set an upper limit for the rate constant for recombination of krUF6 and UF5 after laser photolysis of the UF6 gas sample.

Screening and confirmation criteria for hormone residue analysis using liquid chromatography accurate mass time-of-flight, Fourier transform ion cyclotron resonance and orbitrap mass spectrometry techniques

NARCIS (Netherlands)

Nielen, M.W.F.; Engelen, M.C. van; Zuiderent, R.; Ramaker, R.

2007-01-01

An emerging trend is recognised in hormone and veterinary drug residue analysis from liquid chromatography tandem mass spectrometry (LC/MS/MS) based screening and confirmation towards accurate mass alternatives such as LC coupled with time-of-flight (TOF), Fourier transform ion cyclotron resonance

Mechanical stimulated reaction of metal/polymer mixed powders; Kinzoku/kobunshi kongo funmatsu no kikaiteki reiki hanno

Energy Technology Data Exchange (ETDEWEB)

Tobita, M.; Sakakibara, A.; Takemoto, Y. [Okayama University, Okayama (Japan). Faculty of Engineering; Iwabu, H. [Kurare Co. Ltd., Osaka (Japan)

1999-12-15

Mechanical grinding (MG) with mechanically stimulated reaction was performed on metal/polymer mixed powders. The starting materials used in this study were the metals of Mg, Ti and Mg{sub 2}Ni powders, arid polymer of PTFE, PVC and PE powders. The MG process was investigated using XRD, IR, SEM and TEM. According to XRD results, magnesium fluoride (MgF{sub 2}, TiF{sub 2}) and chloride (MgCl{sub 2}) were detected from MG products of the Mg/PTFE, Ti/PTFE and Mg/PVC blending systems, respectively. Explosive reaction was found during MG of both Mg/PTFE and Ti/PTFE. It was also confirmed by XRD results that the production of MgF{sub 2} had already been formed just before the explosive reaction in Mg/PTFE system. It was found from IR analysis that C-C single bond in the polymers, not only both in PTFE and PVC but also in PE, changed to double bond C=C. Hydrogen produced due to decomposition of PE on blending Mg{sub 2}Ni/PE was absorbed into C-Mg{sub 2}Ni-H as amorphous solutes. These mechanically stimulated reaction was powerful method for decomposition of engineering plastics. (author)

Quinine-Promoted, Enantioselective Boron-Tethered Diels-Alder Reaction by Anomeric Control of Transition State Conformation.

Science.gov (United States)

Scholl, Katie; Dillashaw, John; Timpy, Evan; Lam, Yu-Hong; DeRatt, Lindsey; Benton, Tyler R; Powell, Jacqueline P; Houk, Kendall N; Morgan, Jeremy B

2018-05-01

Diels-Alder reactions of tethered vinyl-metal species offer the opportunity to fashion highly functionalized diol intermediates for synthesis. We have developed the first enantioselective boron-tethered Diels-Alder reaction using quinine as a chiral promoter. Quinine recovery, enantioselectivity enhancement, and manipulation of the cyclohexene core are also investigated. DFT modeling calculations confirm the role of quinine as a bidentate ligand enhancing reaction rates. The enantioselectivity of the cycloaddition is proposed to originate from a boron-centered anomeric effect.

Nanoscale studies of cement chemistry with 15N resonance reaction analysis

International Nuclear Information System (INIS)

Schweitzer, Jeffrey S.; Livingston, Richard A.; Rolfs, Claus; Becker, Hans-Werner; Kubsky, Stefan; Spillane, Timothy; Castellote, Marta; Viedma, Paloma G. de

2005-01-01

Analyses of materials with ion beams have proven to be a valuable technique for describing the spatial distributions of specific elements in host materials. We have applied this technique using the 15 N(p, αγ) 12 C reaction to study the time dependence of the chemical reactions involved in the curing of cement. By using the Dynamitron Tandem accelerator at the Ruhr Universitaet, Bochum, Germany, we have been able to achieve a few nanometer spatial resolution at the surface of cement grains and to study the hydrogen distributions to a depth of about 2 μm. By applying a technique for stopping the chemical reactions at arbitrary times, the time dependence of the chemical reactions involving specific components of cement can be investigated. In addition, the effects of additives on the chemical reactions have been studied, as have materials that are components of concrete

Functional data analysis on ground reaction force of military load carriage increment

Science.gov (United States)

Din, Wan Rozita Wan; Rambely, Azmin Sham

2014-06-01

Analysis of ground reaction force on military load carriage is done through functional data analysis (FDA) statistical technique. The main objective of the research is to investigate the effect of 10% load increment and to find the maximum suitable load for the Malaysian military. Ten military soldiers age 31 ± 6.2 years, weigh 71.6 ± 10.4 kg and height of 166.3 ± 5.9 cm carrying different military load range from 0% body weight (BW) up to 40% BW participated in an experiment to gather the GRF and kinematic data using Vicon Motion Analysis System, Kirstler force plates and thirty nine body markers. The analysis is conducted in sagittal, medial lateral and anterior posterior planes. The results show that 10% BW load increment has an effect when heel strike and toe-off for all the three planes analyzed with P-value less than 0.001 at 0.05 significant levels. FDA proves to be one of the best statistical techniques in analyzing the functional data. It has the ability to handle filtering, smoothing and curve aligning according to curve features and points of interest.

SWAAM-LT: The long-term, sodium/water reaction analysis method computer code

International Nuclear Information System (INIS)

Shin, Y.W.; Chung, H.H.; Wiedermann, A.H.; Tanabe, H.

1993-01-01

The SWAAM-LT Code, developed for analysis of long-term effects of sodium/water reactions, is discussed. The theoretical formulation of the code is described, including the introduction of system matrices for ease of computer programming as a general system code. Also, some typical results of the code predictions for available large scale tests are presented. Test data for the steam generator design with the cover-gas feature and without the cover-gas feature are available and analyzed. The capabilities and limitations of the code are then discussed in light of the comparison between the code prediction and the test data

Development of a novel fingerprint for chemical reactions and its application to large-scale reaction classification and similarity.

Science.gov (United States)

Schneider, Nadine; Lowe, Daniel M; Sayle, Roger A; Landrum, Gregory A

2015-01-26

Fingerprint methods applied to molecules have proven to be useful for similarity determination and as inputs to machine-learning models. Here, we present the development of a new fingerprint for chemical reactions and validate its usefulness in building machine-learning models and in similarity assessment. Our final fingerprint is constructed as the difference of the atom-pair fingerprints of products and reactants and includes agents via calculated physicochemical properties. We validated the fingerprints on a large data set of reactions text-mined from granted United States patents from the last 40 years that have been classified using a substructure-based expert system. We applied machine learning to build a 50-class predictive model for reaction-type classification that correctly predicts 97% of the reactions in an external test set. Impressive accuracies were also observed when applying the classifier to reactions from an in-house electronic laboratory notebook. The performance of the novel fingerprint for assessing reaction similarity was evaluated by a cluster analysis that recovered 48 out of 50 of the reaction classes with a median F-score of 0.63 for the clusters. The data sets used for training and primary validation as well as all python scripts required to reproduce the analysis are provided in the Supporting Information.

Kinetics and Mechanisms of Calcite Reactions with Saline Waters

Energy Technology Data Exchange (ETDEWEB)

Gorman, Brian P [Colorado School of Mines, Golden, CO (United States)

2015-09-02

Project Description: The general objective of the proposed research is to determine the kinetics and mechanisms of calcite reactions with saline waters over a wide range of saline water composition, pCO₂, and modest ranges in T and P. This will be accomplished by studying both reaction rates and solubility from changes in solution chemistry, and making nanoscale observations of calcite precipitate surface morphology and composition at the micro-to-nano-scale to provide an understanding of controlling reaction mechanisms and pathways. The specific objectives necessary to reach the general objective are: a) determination of how pCO₂, Ca²⁺, ionic strength and “foreign” ions influence reaction rates; and b) investigate the influence of these parameters on apparent kinetic solubility from dissolution and precipitation reactions. This information will clearly be central to the construction of reliable reaction-transport models to predict reservoir and formation response to increased CO₂ in saline waters. This program was initially collaborative with John Morse at Texas A&M, however his passing shortly after the beginning of this program resulted in abbreviated research time and effort. Summary of Results: Early studies using electron microscopy and spectroscopy indicated that carbonate precipitation from natural seawater (NSW) conditions onto aragonite substrates was mediated by a surface amorphous calcium carbonate layer. It was hypothesized that this ACC layer (observed after < 5days reaction time) was responsible for the abnormal reaction kinetics and also served as a metastable seed layer for growth of epitaxial aragonite. Further studies of the ACC formation mechanism indicated a strong dependence on the Mg concentration in solution. Subsequent studies at shorter times (10 hrs) on calcite substrates and in a wide range of supersaturation conditions did not indicate any ACC layer. Instead, an epitaxial layer by layer

Compositional analysis of sulfated polysaccharides from sea cucumber (Stichopus japonicus) released by autolysis reaction.

Science.gov (United States)

Song, Shuang; Wu, Sufeng; Ai, Chunqing; Xu, Xin; Zhu, Zhenjun; Cao, Chunyang; Yang, Jingfeng; Wen, Chengrong

2018-07-15

Autolysis is not only a major reason for postharvest quality deterioration of sea cucumber, but also a promising alternative for exogenous protease to produce peptides or polysaccharides. However, little has been known about the effects of autolysis on bioactive polysaccharides of sea cucumber. Concerning the quality and safety of sea cucumber products involved autolysis reaction, the present study focused on the chemical composition of sulfated polysaccharides (SPs) released by autolysis reaction. Chemical analysis indicated that after 3-day autolysis 63% of sulfated polysaccharides were liberated but with protein chains at their reducing ends. Then the composition of SP obtained by autolysis (A-SP) was compared with that of total SPs (T-SP) via a series of analysis techniques, including FTIR, 1 H NMR, HPLC and mass spectroscopy. As indicated by the results, fucan to fucosylated chondroitin sulfate ratio was found high in A-SP compared to T-SP, fucan with a lower molecular weight was the major fraction in A-SP, and the di-sulfated Fuc residue observed in T-SP was absent in A-SP. To conclude, A-SP differed greatly from T-SP in the chemical composition, suggesting possible changes on their bioactivities. Copyright © 2018. Published by Elsevier B.V.

Low-Energy Nuclear Reactions Resulting as Picometer Interactions with Similarity to K-Shell Electron Capture

Science.gov (United States)

Hora, H.; Miley, G. H.; Li, X. Z.; Kelly, J. C.; Osman, F.

2006-02-01

Since the appeal by Brian Josephson at the meeting of the Nobel Laureates July 2004, it seems to be indicated to summarize the following serious, reproducible and confirmed observations on reactions of protons or deuterons incorporated in host metals such as palladium. Some reflections to Rutherford's discovery of nuclear physics, the Cockroft-Oliphant discovery of anomalous low-energy fusion reactions and the chemist Hahn's discovery of fission had to be included. Using gaseous atmosphere or discharges between palladium targets, rather significant results were seen e.g. from the "life after death" heat production of such high values per host atom that only nuclear reactions can be involved. This supports the earlier evaluation of neutron generation in fully reversible experiments with gas discharges hinting that a reasonable screening effect - preferably in the swimming electron layer - may lead to reactions at nuclear distances d of picometers with reaction probability times U of about megaseconds similar to the K-shell capture radioactivity. Further electrolytic experiments led to low-energy nuclear reactions (LENR) where the involvement of pollution could be excluded from the appearance of very seldom rare earth elements. A basically new theory for DD cross-sections is used to confirm the picometer-megasecond reactions of cold fusion. Other theoretical aspects are given from measured heavy element distributions similar to the standard abundance distribution, SAD, in the Universe with consequences on endothermic heavy nuclei generation, magic numbers and to quark-gluon plasmas.

Low-energy nuclear reactions resulting as parametric interactions with similarity to K-shell electron capture

International Nuclear Information System (INIS)

Hora, H.; Miley, G.H.; Li, X.Z.; Kelly, J.C.; Osman, F.

2006-01-01

Since the appeal by Brian Josephson at the meeting of the Nobel Laureates July 2004, it seems to be indicated to summarize the following serious, reproducible and confirmed observations on reactions of protons of deuterons incorporated in host metals such as palladium. Some reflections to Rutherford's discovery of nuclear physics, the Cockcroft Oliphant discovery of anomalous low-energy fusion reactions and the chemist Hahn's discovery of fission had to be included. Using gaseous atmosphere or discharges between palladium targets, rather significant results were seen e.g. from the 'life after death' heat production of such high values per host atom that only nuclear reactions can be involved. This supports the earlier evaluation of neutron generation in fully reversible experiments with gas discharges hinting that a reasonable screening effect - preferably in the swimming electron layer - may lead to reactions at nuclear distances d of pico-meters with reaction probability times U of about mega-seconds similar to the K-shell capture radioactivity. Further electrolytic experiments led to low-energy nuclear reactions (LENR) where the involvement of pollution could be excluded from the appearance of very seldom rare earth elements. A basically new theory for DD cross-sections is used to confirm the pico-meter- mega-second reactions of cold fusion. Other theoretical aspects are given from measured heavy element distributions similar to the standard abundance distribution, SAD, in the Universe with consequences on endothermic heavy nuclei generation, magic numbers and to quark-gluon plasmas. (authors)

Consequence analysis of IWTS metal water reactions (Fauske and Associates report 99-35)

International Nuclear Information System (INIS)

DUNCAN, D.R.

1999-01-01

The report describes the consequences of postulated thermally unstable conditions in the IWTS knock out pot. The consequence analysis shows that both the knock out pot and particulate bed will stay intact, and that releases will be minor. Reaction rate limitations prevent knock out pot pressure and/or temperature from even approaching values that would threaten structural integrity. Source term calculations based on a particle bed with a homogeneous mixture of metal and oxide particles yield a release above the K Basin pool of about 12 grams

Immediate and delayed cutaneous reactions to radiocontrast media.

Science.gov (United States)

Brockow, Knut

2012-01-01

Hypersensitivity reactions to contrast media (CM) are frequent causes of anaphylaxis and drug exanthemas. Adverse events after CM exposure are classified into immediate (≤1 h) and non-immediate reactions (>1 h), with differing mechanisms. In the majority of patients with immediate reactions, IgE-mediated allergy cannot be demonstrated, and the underlying mechanism remains unknown. However, recent data have provided evidence for skin test positivity and/or specific IgE in some patients. T cell-mediated hypersensitivity is the responsible mechanism for the majority of non-immediate skin eruptions. These insights have consequences for diagnosis and prevention. Skin testing evolves to be a useful tool for diagnosis of CM allergy. Skin tests have been employed to confirm this hypersensitivity. Previous reactors have an increased risk to develop new reactions upon repeated exposure; however, other risk factors are poorly defined. The use of skin tests for the selection of a 'safe' CM is under investigation with promising results. In vitro tests to search for CM-specific cell activation include flow cytometric approaches, lymphocyte cultures and construction of cell lines and hybridomas. Premedication of previous reactors is common practice among radiologists; however, breakthrough reactions are a concern, and physicians should not rely on the efficacy of pharmacological premedication. Copyright © 2012 S. Karger AG, Basel.

The French methodology for EBS confirmation and demonstration

International Nuclear Information System (INIS)

Plas, F.; Voinis, S.; Mayer, S.

2007-01-01

The December 30, 1991 French Waste Act entrusted ANDRA, the French national agency for radioactive waste management, with the task of assessing the feasibility of deep geological disposal of high- and medium-level long-lived waste (HLW and ILW, respectively C-waste and B-waste types in French) plus spent fuel (CU in French). In that context, the 'Dossier 2005 Argile' submitted by ANDRA presents the feasibility assessment - with regard to the technical capacity to accommodate all wastes, to reversibility, and to safety - of a radioactive waste disposal in a clay formation studied at the Meuse/Haute-Marne URL. This report was built upon an iterative approach between site characterisation, design, modelling, phenomenological analysis and safety analysis, in which two principles always guided the elaboration of the safety case: the principle of robustness - repository components must maintain their functionality given reasonable solicitations, taking into account uncertainties on the nature and level of these solicitations; and the principle of demonstrability - safety must be verified without requiring complex demonstrations, and based on multiple lines of evidence/argument (numerical simulation, qualitative arguments such as use of natural analogues, experiments and technological demonstrators). In that respect, the EBS definition, demonstration and confirmation of design is a part of the overall safety case. The 'Dossier 2005 Argile' was submitted to three independent peer reviews. The aim. of this article is to present the methodology that ANDRA implemented in the context of 'Dossier 2005 Argile' for defining, demonstrating and confirming the EBS design as well as the future programme with respect with the new Act of 28 June 2006. (author)

Variation in reaction norms: Statistical considerations and biological interpretation.

Science.gov (United States)

Morrissey, Michael B; Liefting, Maartje

2016-09-01

Analysis of reaction norms, the functions by which the phenotype produced by a given genotype depends on the environment, is critical to studying many aspects of phenotypic evolution. Different techniques are available for quantifying different aspects of reaction norm variation. We examine what biological inferences can be drawn from some of the more readily applicable analyses for studying reaction norms. We adopt a strongly biologically motivated view, but draw on statistical theory to highlight strengths and drawbacks of different techniques. In particular, consideration of some formal statistical theory leads to revision of some recently, and forcefully, advocated opinions on reaction norm analysis. We clarify what simple analysis of the slope between mean phenotype in two environments can tell us about reaction norms, explore the conditions under which polynomial regression can provide robust inferences about reaction norm shape, and explore how different existing approaches may be used to draw inferences about variation in reaction norm shape. We show how mixed model-based approaches can provide more robust inferences than more commonly used multistep statistical approaches, and derive new metrics of the relative importance of variation in reaction norm intercepts, slopes, and curvatures. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

Single-Atom Catalysts of Precious Metals for Electrochemical Reactions.

Science.gov (United States)

Kim, Jiwhan; Kim, Hee-Eun; Lee, Hyunjoo

2018-01-10

Single-atom catalysts (SACs), in which metal atoms are dispersed on the support without forming nanoparticles, have been used for various heterogeneous reactions and most recently for electrochemical reactions. In this Minireview, recent examples of single-atom electrocatalysts used for the oxygen reduction reaction (ORR), hydrogen oxidation reaction (HOR), hydrogen evolution reaction (HER), formic acid oxidation reaction (FAOR), and methanol oxidation reaction (MOR) are introduced. Many density functional theory (DFT) simulations have predicted that SACs may be effective for CO 2 reduction to methane or methanol production while suppressing H 2 evolution, and those cases are introduced here as well. Single atoms, mainly Pt single atoms, have been deposited on TiN or TiC nanoparticles, defective graphene nanosheets, N-doped covalent triazine frameworks, graphitic carbon nitride, S-doped zeolite-templated carbon, and Sb-doped SnO 2 surfaces. Scanning transmission electron microscopy, extended X-ray absorption fine structure measurement, and in situ infrared spectroscopy have been used to detect the single-atom structure and confirm the absence of nanoparticles. SACs have shown high mass activity, minimizing the use of precious metal, and unique selectivity distinct from nanoparticle catalysts owing to the absence of ensemble sites. Additional features that SACs should possess for effective electrochemical applications were also suggested. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Numerical analysis for Darcy-Forchheimer flow in presence of homogeneous-heterogeneous reactions

Directory of Open Access Journals (Sweden)

Muhammad Ijaz Khan

Full Text Available A mathematical study is presented to investigate the influences of homogeneous and heterogeneous reactions in local similar flow caused by stretching sheet with a non-linear velocity and variable thickness. Porous medium effects are characterized by using Darcy-Forchheimer porous-media. A simple isothermal model of homogeneous-heterogeneous reactions is used. The multiphysical boundary value problem is dictated by ten thermophysical parameters: ratio of mass diffusion coefficients, Prandtl number, local inertia coefficient parameter, inverse Darcy number, shape parameter, surface thickness parameter, Hartman number, Homogeneous heat reaction, strength of homogeneous-heterogeneous reactions and Schmidt number. Resulting systems are computed by Runge-Kutta-Fehlberg method. Different shapes of velocity are noticed for n > 1 and n < 1. Keywords: Homogeneous-heterogeneous reactions, Non Darcy porous medium, Variable sheet thickness, Homogeneous heat reaction with stoichiometric coefficient, Runge-Kutta-Fehlberg method

Vaccine effectiveness against medically attended laboratory-confirmed influenza in Japan, 2011-2012 Season.

Directory of Open Access Journals (Sweden)

Motoi Suzuki

Full Text Available The objective of this study was to estimate influenza vaccine effectiveness (VE against medically attended, laboratory-confirmed influenza during the 2011-2012 season in Japan using a test-negative case-control study design. The effect of co-circulating non-influenza respiratory viruses (NIRVs on VE estimates was also explored. Nasopharyngeal swab samples were collected from outpatients with influenza-like illnesses (ILIs in a community hospital in Nagasaki, Japan. Thirteen respiratory viruses (RVs, including influenza A and B, were identified from the samples using a multiplex polymerase chain reaction. The difference in VE point estimates was assessed using three different controls: ILI patients that tested negative for influenza, those that tested negative for all RVs, and those that tested positive for NIRVs. The adjusted VE against medically attended, laboratory-confirmed influenza using all influenza-negative controls was 5.3% (95% confidence interval [CI], -60.5 to 44.1. The adjusted VEs using RV-negative and NIRV-positive controls were -1.5% (95% CI, -74.7 to 41 and 50% (95% CI, -43.2 to 82.5, respectively. Influenza VE was limited in Japan during the 2011-2012 season. Although the evidence is not conclusive, co-circulating NIRVs may affect influenza VE estimates in test-negative case-control studies.

Study of reactions for the production of uranium titrafluoride and uranium hexafluoride

International Nuclear Information System (INIS)

Guzella, M.F.R.

1985-01-01

The main production processes of uranium hexafluoride in pilot plants and industrial facilities are described. The known reactions confirmed in laboratory experiments that lead to Uf 6 or other intermediate fluorides are discussed. For the purpose of determining a thermodinamically feasible reaction involving the sulfur hexafluoride as fluorinating agent, a mock-up facility was designed and constructed as a part of the R and D work planned at the CDTN (Nuclebras Center for Nuclear Technology Development). IN the uranium tatrafluoride synthesis employing U 3 O 8 and SF 6 several experimental parameters are studied. The reaction time, gasflow, temperature and stoechiometic relations among reagents are described in detail. (Author) [pt

Incidental Risk of Type 2 Diabetes Mellitus among Patients with Confirmed and Unconfirmed Prediabetes.

Directory of Open Access Journals (Sweden)

Kimberly D Brunisholz

Full Text Available To determine the risk of type 2 diabetes (T2DM diagnosis among patients with confirmed and unconfirmed prediabetes (preDM relative to an at-risk group receiving care from primary care physicians over a 5-year period.Utilizing data from the Intermountain Healthcare (IH Enterprise Data Warehouse (EDW from 2006-2013, we performed a prospective analysis using discrete survival analysis to estimate the time to diagnosis of T2DM among groups.Adult patients who had at least one outpatient visit with a primary care physician during 2006-2008 at an IH clinic and subsequent visits through 2013. Patients were included for the study if they were (a at-risk for diabetes (BMI ≥ 25 kg/m2 and one additional risk factor: high risk ethnicity, first degree relative with diabetes, elevated triglycerides or blood pressure, low HDL, diagnosis of gestational diabetes or polycystic ovarian syndrome, or birth of a baby weighing >9 lbs; or (b confirmed preDM (HbA1c ≥ 5.7-6.49% or fasting blood glucose 100-125 mg/dL; or (c unconfirmed preDM (documented fasting lipid panel and glucose 100-125 mg/dL on the same day.Of the 33,838 patients who were eligible for study, 57.0% were considered at-risk, 38.4% had unconfirmed preDM, and 4.6% had confirmed preDM. Those with unconfirmed and confirmed preDM tended to be Caucasian and a greater proportion were obese compared to those at-risk for disease. Patients with unconfirmed and confirmed preDM tended to have more prevalent high blood pressure and depression as compared to the at-risk group. Based on the discrete survival analyses, patients with unconfirmed preDM and confirmed preDM were more likely to develop T2DM when compared to at-risk patients.Unconfirmed and confirmed preDM are strongly associated with the development of T2DM as compared to patients with only risk factors for disease.

Electro-deposition of Pd on Carbon paper and Ni foam via surface limited redox-replacement reaction for oxygen reduction reaction

International Nuclear Information System (INIS)

Modibedi, Remegia M.; Mathe, Mkhulu K.; Motsoeneng, Rapelang G.; Khotseng, Lindiwe E.; Ozoemena, Kenneth I.; Louw, Eldah K.

2014-01-01

Pd nanostructured catalysts were electrodeposited by surface-limited redox replacement reactions using the electrochemical atomic layer deposition technique. Carbon paper and Ni foam were used as substrates for the electrodeposition of the metal. Supported nanostructured Pd electrodes were characterized using electrochemical methods and scanning electron microscopy. Carbon paper and Ni foam produced good quality deposits with some agglomeration on Ni foam. The EDX profiles confirmed the presence of Pd particles. Cyclic voltammograms of the electrodeposited Pd on substrates showed features characteristic of polycrystalline Pd electrodes. In the acidic electrolyte a very weak oxygen reduction reaction (ORR) activity was observed on Pd/Carbon paper electrode when compared to Pd/Ni foam electrode. The Pd/Ni foam electrode showed improved ORR activity in alkaline medium

Ambulatory Measurement of Ground Reaction Forces

NARCIS (Netherlands)

Veltink, Peter H.; Liedtke, Christian; Droog, Ed

2004-01-01

The measurement of ground reaction forces is important in the biomechanical analysis of gait and other motor activities. It is the purpose of this study to show the feasibility of ambulatory measurement of ground reaction forces using two six degrees of freedom sensors mounted under the shoe. One

Chemical boundary layers in CVD II. Reversible reactions

NARCIS (Netherlands)

Croon, de M.H.J.M.; Giling, L.J.

1990-01-01

In addition to irreversible reactions, which were treated in part I, reversible reactions in the gas phase have beenstudied using the concept of the chemical boundary layer. The analysis is given for the situations in which either the forwardor the back reaction is dominant. Two conceptual models

The effect of moderators on the reactions of hot hydrogen atoms with methane

CERN Document Server

Estrup, Peder J.

1960-01-01

The reaction of recoil tritium with methane has been examined in further detail. The previous hypothesis that this system involves a hot displacement reaction of high kinetic energy hydrogen to give CH$_{3}$T, CH$_{2}$T and HT is confirmed. The effect of moderator on this process is studied by the addition of noble gases. As predicted these gases inhibit the hot reaction action, their efficiency in this respect being He > Ne > A > Se. The data are quantitatively in accord with a theory of hot atom kinetics. The mechanism of the hot displacement process is briefly discussed.

Correlations between energy and mass partition in the damped reaction 165Ho+74Ge at Elab=8.5 MeV/nucleon

International Nuclear Information System (INIS)

Toke, J.; Planeta, R.; Schroeder, W.U.; Huizenga, J.R.

1991-01-01

Data from a kinematical coincidence experiment on the damped reaction 165 Ho+ 74 Ge at 8.5 MeV/nucleon have been reanalyzed. Although the new analysis confirms the presence of some correlations between the excitation-energy division and the mass asymmetry, the magnitude of these correlations is found to be significantly smaller than that previously reported. Proton-neutron symmetry of the mechanism of heat generation through nucleon exchange is revealed and a possible acceptor-donor asymmetry of this mechanism is discussed

Determination of transport and reaction swarm coefficients from the analysis of complex transient pulses from the pulsed Townsend experiment

International Nuclear Information System (INIS)

Bekstein, A; De Urquijo, J; Rodríguez-Luna, J C; Juárez, A M; Ducasse, O

2012-01-01

We present in this paper the interpretation and analysis of transient pulses from a pulsed Townsend experiment by solving the continuity equations of the charged carriers (electrons and ions) involved in the avalanche. The set of second order partial differential equations is solved by SIMAV, a simulator designed specifically for the pulsed Townsend avalanche. Complex situations involving processes such as electron detachment, ion-molecule reactions, Penning ionization and secondary electron emission from ion impact at the cathode, virtually impossible to solve analytically, are discussed here to illustrate the capability of the simulator to help explain the various reaction processes involved in the avalanche, and also to derive some of the transport and reaction coefficients.

Bacteriologically confirmed tuberculosis in children

International Nuclear Information System (INIS)

Ozere, I.; Sele, A.; Ozolina, A.

2005-01-01

Tuberculosis in children and adults is a growing problem with important public health implications. In Latvia the incidence of tuberculosis (TB) in children up to age 14 has increased from 7,1 per 100000 in 1992 to 28,8 per 100000 in 2003. The diagnosis of TB is confirmed by isolation and identification of M. tuberculosis (MT) from clinical specimen. Confirmation of the disease, however, is difficult in children due to poor bacilli excretion and even under the best circumstances only about 30-40% of pediatric TB cases are proved bacteriologically. Of the 370 pediatric TB cases diagnosed between January 1, 2001 and December 1, 2003 in Latvia, 53 (14,3%) were confirmed bacteriologically. The clinical, radiological, immunological and anamnestic features of confirmed TB can serve as cornerstones for diagnosing of TB, when culture is not available. Objective To evaluate the sensitivity of diagnostic criteria of TB, clinical and radiological manifestation of TB and drug susceptibility of MT isolated also. Methods All consecutive children (53 in total) up to age 14 diagnosed with bacteriologically confirmed TB during 01.01.2001. -01.12.2003. were prospectively evaluated for reasons mentioned above. Results Of the 53 children identified all but one had respiratory tract TB. 17(32,1 %) children were under 4 years of age, 9 (17%) children were 5-9 years old, but 27 (50,9%) patients were 10-14 years old. During evaluation data on TB source case were found in addition in 13 children and total TB contact history was positive in 37 (69,8%) patients. All clinical and radiographical forms of respiratory tract TB were diagnosed. The most common encountered forms were intrathoracic adenopathy in 10 (18,9%) cases and TB pneumonia in 6 (11,3%) cases in children aged 10-14 years. lnthrathoracic adenopathy associated with segmental parenchymal lesion was the most common form in children under 4 years of age -7 (13,2%) cases respectively. Conclusions 1. The clinical and radiological

Hypersensitivity reactions to anticancer agents: Data mining of the public version of the FDA adverse event reporting system, AERS

Directory of Open Access Journals (Sweden)

Sakaeda Toshiyuki

2011-10-01

Full Text Available Abstract Background Previously, adverse event reports (AERs submitted to the US Food and Drug Administration (FDA database were reviewed to confirm platinum agent-associated hypersensitivity reactions. The present study was performed to confirm whether the database could suggest the hypersensitivity reactions caused by anticancer agents, paclitaxel, docetaxel, procarbazine, asparaginase, teniposide, and etoposide. Methods After a revision of arbitrary drug names and the deletion of duplicated submissions, AERs involving candidate agents were analyzed. The National Cancer Institute Common Terminology Criteria for Adverse Events version 4.0 was applied to evaluate the susceptibility to hypersensitivity reactions, and standardized official pharmacovigilance tools were used for quantitative detection of signals, i.e., drug-associated adverse events, including the proportional reporting ratio, the reporting odds ratio, the information component given by a Bayesian confidence propagation neural network, and the empirical Bayes geometric mean. Results Based on 1,644,220 AERs from 2004 to 2009, the signals were detected for paclitaxel-associated mild, severe, and lethal hypersensitivity reactions, and docetaxel-associated lethal reactions. However, the total number of adverse events occurring with procarbazine, asparaginase, teniposide, or etoposide was not large enough to detect signals. Conclusions The FDA's adverse event reporting system, AERS, and the data mining methods used herein are useful for confirming drug-associated adverse events, but the number of co-occurrences is an important factor in signal detection.

Performance confirmation data acquisition system

International Nuclear Information System (INIS)

McAffee, D.A.; Raczka, N.T.

1997-01-01

As part of the Viability Assessment (VA) work, this QAP-3-9 document presents and evaluates a comprehensive set of viable concepts for collecting Performance Confirmation (PC) related data. The concepts include: monitoring subsurface repository air temperatures, humidity levels and gaseous emissions via the subsurface ventilation systems, and monitoring the repository geo-technical parameters and rock mass from bore-holes located along the perimeter main drifts and throughout a series of human-rated Observation Drifts to be located in a plane 25 meters above the plane of the emplacement drifts. A key element of this document is the development and analysis of a purposed multi-purpose Remote Inspection Gantry that would provide direct, real-time visual, thermal, and radiological monitoring of conditions inside operational emplacement drifts and close-up observations of in-situ Waste Packages. Preliminary finite-element analyses are presented that indicate the technological feasibility of operating an inspection gantry inside the operational emplacement drifts for short inspection missions lasting 2--3 hours. Overall reliability, availability, and maintainability of the PC data collection concepts are discussed. Preliminary concepts for PC data collection network are also provided

Performance confirmation data acquisition system

Energy Technology Data Exchange (ETDEWEB)

McAffee, D.A.; Raczka, N.T. [Yucca Mountain Project, Las Vegas, NV (United States)

1997-12-31

As part of the Viability Assessment (VA) work, this QAP-3-9 document presents and evaluates a comprehensive set of viable concepts for collecting Performance Confirmation (PC) related data. The concepts include: monitoring subsurface repository air temperatures, humidity levels and gaseous emissions via the subsurface ventilation systems, and monitoring the repository geo-technical parameters and rock mass from bore-holes located along the perimeter main drifts and throughout a series of human-rated Observation Drifts to be located in a plane 25 meters above the plane of the emplacement drifts. A key element of this document is the development and analysis of a purposed multi-purpose Remote Inspection Gantry that would provide direct, real-time visual, thermal, and radiological monitoring of conditions inside operational emplacement drifts and close-up observations of in-situ Waste Packages. Preliminary finite-element analyses are presented that indicate the technological feasibility of operating an inspection gantry inside the operational emplacement drifts for short inspection missions lasting 2--3 hours. Overall reliability, availability, and maintainability of the PC data collection concepts are discussed. Preliminary concepts for PC data collection network are also provided.

Quantification, confirmation and screening capability of UHPLC coupled to triple quadrupole and hybrid quadrupole time-of-flight mass spectrometry in pesticide residue analysis.

Science.gov (United States)

Grimalt, Susana; Sancho, Juan V; Pozo, Oscar J; Hernández, Félix

2010-04-01

The potential of three mass spectrometry (MS) analyzers (triple quadrupole, QqQ; time of flight, TOF; and quadrupole time of flight, QTOF) has been investigated and compared for quantification, confirmation and screening purposes in pesticide residue analysis of fruit and vegetable samples. For this purpose, analytical methodology for multiresidue determination of 11 pesticides, taken as a model, has been developed and validated in nine food matrices for the three mass analyzers coupled to ultra high pressure liquid chromatography. In all cases, limits of quantification around 0.01 mg/kg were reached, fulfilling the most restrictive case of baby-food analysis. Regarding absolute sensitivity, the lower limits of detection were obtained, as expected, for QqQ (100 fg), whereas slightly higher limits (300 fg) were obtained for both TOF and QTOF. Confirmative capacity of each analyzer was studied for each analyte based on the identification points (IPs) criterion, useful for a comprehensive comparison. QTOF mass analyzer showed the highest confirmatory capacity, although QqQ normally led to sufficient number of IPs, even at lower concentration levels. The potential of TOF MS was also investigated for screening purposes. To this aim, around 50 commercial fruits and vegetables samples were analyzed, searching for more than 400 pesticides. TOF MS proved to be an attractive analytical tool for rapid detection and reliable identification of a large number of pesticides thanks to the full spectrum acquisition at accurate mass with satisfactory sensitivity. This process is readily boosted when combined with specialized software packages, together with theoretical exact mass databases. Several pesticides (e.g. carbendazim in citrus and indoxacarb in grape) were detected in the samples. Further unequivocal confirmation of the identity was performed using reference standards and/or QTOF MS/MS experiments. Copyright 2010 John Wiley & Sons, Ltd.

Sugarcane bagasse gasification: Global reaction mechanism of syngas evolution

International Nuclear Information System (INIS)

Ahmed, I.I.; Gupta, A.K.

2012-01-01

Highlights: ► Gasification of sugarcane bagasse has been investigated using a semi batch reactor. ► Global reaction mechanism combining pyrolysis and gasification reactions is presented. ► High flow rates of syngas supported fragmentation and secondary reactions. ► CO flow rate increased at higher heating rates at the expense of CO 2 production. ► At high temperatures merger between pyrolysis and char gasification occurs. -- Abstract: Steam gasification of sugarcane bagasse has been investigated. A semi batch reactor with a fixed amount of sugarcane bagasse sample placed in steady flow of high temperature steam at atmospheric pressure has been used. The gasification of bagasse was examined at reactor and steam temperatures of 800, 900 and 1000 °C. The evolution of syngas flow rate and chemical composition has been monitored. The evolution of chemical composition and total flow rate of the syngas has been used to formulate a global reaction mechanism. The mechanism combines pyrolysis reaction mechanisms from the literature and steam gasification/reforming reactions. Steam gasification steps include steam–hydrocarbons reforming, char gasification and water gas shift reactions. Evidence of fragmentation, secondary ring opening reactions and tertiary reactions resulting in formation of gaseous hydrocarbons is supported by higher flow rates of syngas and hydrogen at high heating rates and high reactor temperatures. Increase in carbon monoxide flow rate at the expense of carbon dioxide flow rate with the increase in reactor temperature has been observed. This increase in the ratio of CO/CO 2 flow rate confirms the production of CO and CO 2 from the competing reaction routes. At 1000 °C gasification a total merging between the pyrolysis step and the char gasification step has been observed. This is attributed to acceleration of char gasification reactions and acceleration of steam–hydrocarbons reforming reactions. These hydrocarbons are the precursors to

[Electromagnetic studies of nuclear structure and reactions

International Nuclear Information System (INIS)

1992-01-01

The experimental goals are focused on developing an understanding of strong interactions and the structure of hadronic systems by determination of the electromagnetic response; these goals will be accomplished through coincidence detection of final states. Nuclear modeling objectives are to organize and interpret the data through a consistent description of a broad spectrum of reaction observables; calculations are performed in a nonrelativistic diagrammatic framework as well as a relativistic QHD approach. Work is described according to the following arrangement: direct knockout reactions (completion of 16 O(e,e'p), 12 C(e,e'pp) progress, large acceptance detector physics simulations), giant resonance studies (intermediate-energy experiments with solid-state detectors, the third response function in 12 C(e,e'p 0 ) and 16 O(e,e'p 0 ), comparison of the 12 C(e, e'p 0 ) and 16 O(e,e'p 3 ) reactions, quadrupole strength in the 16 O(e,e'α 0 ) reaction, quadrupole strength in the 12 C(e,e'α) reaction, analysis of the 12 C(e,e'p 1 ) and 16 O(e,e'p 3 ) angular distributions, analysis of the 40 Ca(e,e'x) reaction at low q, analysis of the higher-q 12 C(e,e'x) data from Bates), models of nuclear structure (experimental work, Hartree-Fock calculations, phonon excitations in spherical nuclei, shell model calculations, variational methods for relativistic fields), and instrumentation development efforts (developments at CEBAF, CLAS contracts, BLAST developments)

Charge exchange (p,n) reactions to the isobaric analog states of high Z nuclei: 73< or =Z< or =92

International Nuclear Information System (INIS)

Hansen, L.F.; Grimes, S.M.; Poppe, C.H.; Wong, C.

1983-01-01

Differential cross sections have been measured for the (p,n) reaction to the isobaric analog states of 181 Ta, 197 Au, 209 Bi, 232 Th, and 238 U at an incident energy of 27 MeV. Because of the importance of collective effects in this mass region, coupled-channel calculations have been carried out in the analysis of the data. Optical potentials obtained from the Lane model for the charge exchange reaction have been used in the simultaneous analysis of coupled proton and neutron channels. The sensitivity of the calculations to the different couplings between the levels and to the magnitude of the isovector potentials, V 1 and W 1 , is discussed. The good agreement obtained between the measured and calculated (p,n) angular distributions to the analog state confirms the validity of the Lane formalism for high-Z nuclei (Z> or =50). Elastic neutron differential cross sections inferred from the coupled-channel analysis are compared with measurements available in the literature in the energy range 7--8 MeV. The results of these calculations agree with the measured values as well as the results of calculations made using global neutron optical potential parameters optimized to fit neutron data

Nuclear reaction analysis (NRA) for trace element detection

Energy Technology Data Exchange (ETDEWEB)

Doebeli, M. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Noll, K. [Bern Univ. (Switzerland)

1997-09-01

Ion beam induced nuclear reactions can be used to analyse trace element concentrations in materials. The method is especially suited for the detection of light contaminants in heavy matrices. (author) 3 figs., 2 refs.

Laboratory Processes for Confirmation of Lymphogranuloma Venereum Infection During a 2015 Investigation of a Cluster of Cases in the United States.

Science.gov (United States)

Kersh, Ellen N; Pillay, Allan; de Voux, Alex; Chen, Cheng

2017-11-01

In September 2015, the Centers for Disease Control and Prevention were notified of a suspected outbreak investigation of lymphogranuloma venereum (LGV) cases by the Michigan Department of Health and Human Services. The Centers for Disease Control and Prevention offered support with a laboratory-developed polymerase chain reaction test for LGV. This note describes the laboratory workflow and procedures used for the laboratory confirmation of LGV infection.

Clonality assessment of lymphoproliferative lesions using the polymerase chain reaction: An analysis of two methods

Directory of Open Access Journals (Sweden)

Nikhil Moorchung

2011-01-01

Full Text Available Background: Lymphoid malignancies are a heterogeneous group of disorders which may be difficult to differentiate from reactive proliferations even after immunohistochemistry. Polymerase chain reaction (PCR is believed to be a good adjunct tool for diagnosis. Materials and Methods: We examined 24 cases of neoplastic and non-neoplastic lymphoproliferative lesions in this study and evaluated the PCR as an additional tool in the confirmation of the diagnosis. Two different PCR methodologies were evaluated. Results: In the evaluation of the T-cell PCR, it was seen that the correlation using both the commercial kits and the custom-synthesized primers was highly significant at a P value of 0.05. Conclusions: Both the methods showed an excellent concordance for T-cell γ gene rearrangements, However, the same was not seen in the B-cell receptor rearrangements. This may be because of the small sample size or the inability of consensus V primers to recognize complementary DNA sequences in all of the V segments.

Principal component analysis of biometric traits to reveal body confirmation in local hill cattle of Himalayan state of Himachal Pradesh, India.

Science.gov (United States)

Verma, Deepak; Sankhyan, Varun; Katoch, Sanjeet; Thakur, Yash Pal

2015-12-01

In the present study, biometric traits (body length [BL], heart girth [HG], paunch girth (PG), forelimb length (FLL), hind limb length (HLL), face length, forehead width, forehead length, height at hump, hump length (HL), hook to hook distance, pin to pin distance, tail length (TL), TL up to switch, horn length, horn circumference, and ear length were studied in 218 adult hill cattle of Himachal Pradesh for phenotypic characterization. Morphological and biometrical observations were recorded on 218 hill cattle randomly selected from different districts within the breeding tract. Multivariate statistics and principal component analysis are used to account for the maximum portion of variation present in the original set of variables with a minimum number of composite variables through Statistical software, SAS 9.2. Five components were extracted which accounted for 65.9% of variance. The first component explained general body confirmation and explained 34.7% variation. It was represented by significant loading for BL, HG, PG, FLL, and HLL. Communality estimate ranged from 0.41 (HL) to 0.88 (TL). Second, third, fourth, and fifth component had a high loading for tail characteristics, horn characteristics, facial biometrics, and rear body, respectively. The result of component analysis of biometric traits suggested that indigenous hill cattle of Himachal Pradesh are small and compact size cattle with a medium hump, horizontally placed short ears, and a long tail. The study also revealed that factors extracted from the present investigation could be used in breeding programs with sufficient reduction in the number of biometric traits to be recorded to explain the body confirmation.

Component Analysis of Sweet BV and Clinical Trial on Antibody Titer and Allergic Reactions

OpenAIRE

Ki Rok, Kwon; Suk Ho, Choi; Bae Chun Cha

2006-01-01

Objectives : The aim of this study was to observe prevention of allergic reactions of Sweet Bee Venom (removing enzyme components from Bee Venom). Methods : Content analysis of Sweet Bee Venom and Bee Venom was rendered using HPLC method and characterization of Anti-Sweet Bee Venom in Rabbit Serum. Clinical observation was conducted for inducement of allergic responses to Sweet BV. Results : 1. Analyzing melittin content using HPLC, Sweet BV contained 34.9% more melittin than Bee venom ...

Culture confirmation of tuberculosis cases in Birmingham, UK.

Science.gov (United States)

Hayer, Kalbir S; Sitch, Alice J; Dedicoat, Martin; Wood, Annette L

2013-10-01

The proportion of culture-confirmed tuberculosis (TB) cases in Birmingham had gradually decreased to less than 65% in 2008. Reasons for this were unclear, therefore this study assessed diagnostic methods used for confirming TB and reviewed factors involved in positive culture. A cross-sectional study was carried out. A list of notified TB cases for Birmingham in those aged 16 y and over in 2009 was collated. Where no positive culture was recorded, further data were collected from hospital databases and case notes. Of 449 TB cases, 419 (93%) had samples taken for culture testing. Of all cases, 309 (69%) were confirmed by culture testing; of those receiving culture testing, 73% were confirmed. Pulmonary TB was identified as a predictor of positive culture in both the unadjusted and adjusted analyses: odds ratio (OR) 2.05, 95% confidence interval (CI) 1.32-3.19, and OR 2.32, 95% CI 1.29-4.17, respectively. Gender, age, ethnicity, UK born, and treatment delay were not significantly associated with positive culture. Of 140 cases not confirmed by culture, 129 (92%) had their diagnosis supported by at least one other test. The vast majority of TB cases had microbiological specimens taken to help confirm the disease. Furthermore, culture confirmation rates in Birmingham were meeting national targets in 2009. However culture confirmation rates were significantly lower in extrapulmonary TB, therefore further work is suggested in this group. The role of other investigations (e.g. interferon-gamma release assay (IGRA), Mantoux) is unclear. Further collaboration between clinicians, histopathologists, and microbiologists is advised to ensure samples are sent appropriately and culture confirmation is optimized.

Investigation of the 10B(n,t) reaction cross-section in the subthreshold energy region

International Nuclear Information System (INIS)

Kornilov, N.V.; Balitskij, A.V.; Baryba, V.Ya.; Druzhnin, V.I.; Kagalenko, A.B.; Kharitonov, A.K.

1991-01-01

The 10 B(n,t) reaction cross-section has been measured at incident neutron energies of 0.025 eV, 420 KeV and 5 MeV. A detailed description of the experimental technique and the Monte Carlo simulation is given. It was confirmed that the cross-section of this reaction in the subthreshold region is non-zero. The recommended value of the 10 B(n,t) reaction cross-section at thermal is 8.5±2.0 mb. (author). 16 refs, 3 figs

Analysis of ping-pong reaction mechanisms by positional isotope exchange. Application to galactose-1-phosphate uridyltransferase

International Nuclear Information System (INIS)

Hester, L.S.; Raushel, F.M.

1987-01-01

A new positional isotope exchange method has been developed that can be used for the analysis of enzyme-catalyzed reactions which have ping-pong kinetic mechanisms. The technique can be used to measure the relative rates of ligand dissociation from enzyme-product complexes. Enzyme is incubated with the labeled substrate and an excess of the corresponding unlabeled product. The partitioning of the enzyme-product complex back toward free enzyme is determined from the rate of positional isotope exchange within the original labeled substrate. The partitioning of the enzyme-product complex forward toward free enzyme is determined from the rate of formation of totally unlabeled substrate. It has been shown that the ratio of the two rates provides a lower limit for the release of product from the enzyme-product complex. The technique has been applied to the reaction catalyzed by galactose-1-phosphate uridyltransferase. The lower limit for the release of glucose 1-phosphate from the uridyl-enzyme relative to the maximal velocity of the reverse reaction was determined to be 3.4 +/- 0.5

Test analysis and research on static choice reaction ability of commercial vehicle drivers

Science.gov (United States)

Zhang, Lingchao; Wei, Lang; Qiao, Jie; Tian, Shun; Wang, Shengchang

2017-03-01

Drivers' choice reaction ability has a certain relation with safe driving. It has important significance to research its influence on traffic safety. Firstly, the paper uses a choice reaction detector developed by research group to detect drivers' choice reaction ability of commercial vehicles, and gets 2641 effective samples. Then by using mathematical statistics method, the paper founds that average reaction time from accident group has no difference with non-accident group, and then introduces a variance rate of reaction time as a new index to replace it. The result shows that the test index choice reaction errors and variance rate of reaction time have positive correlations with accidents. Finally, according to testing results of the detector, the paper formulates a detection threshold with four levels for helping transportation companies to assess commercial vehicles drivers.

Genetic polymorphisms of the IL6 and NOD2 genes are risk factors for inflammatory reactions in leprosy.

Science.gov (United States)

Sales-Marques, Carolinne; Cardoso, Cynthia Chester; Alvarado-Arnez, Lucia Elena; Illaramendi, Ximena; Sales, Anna Maria; Hacker, Mariana de Andréa; Barbosa, Mayara Garcia de Mattos; Nery, José Augusto da Costa; Pinheiro, Roberta Olmo; Sarno, Euzenir Nunes; Pacheco, Antonio Guilherme; Moraes, Milton Ozório

2017-07-01

The pathways that trigger exacerbated immune reactions in leprosy could be determined by genetic variations. Here, in a prospective approach, both genetic and non-genetic variables influencing the amount of time before the development of reactional episodes were studied using Kaplan-Meier survival curves, and the genetic effect was estimated by the Cox proportional-hazards regression model. In a sample including 447 leprosy patients, we confirmed that gender (male), and high bacillary clinical forms are risk factors for leprosy reactions. From the 15 single nucleotide polymorphisms (SNPs) at the 8 candidate genes genotyped (TNF/LTA, IFNG, IL10, TLR1, NOD2, SOD2, and IL6) we observed statistically different survival curves for rs751271 at the NOD2 and rs2069845 at the IL6 genes (log-rank p-values = 0.002 and 0.023, respectively), suggesting an influence on the amount of time before developing leprosy reactions. Cox models showed associations between the SNPs rs751271 at NOD2 and rs2069845 at IL6 with leprosy reactions (HRGT = 0.45, p = 0.002; HRAG = 1.88, p = 0.0008, respectively). Finally, IL-6 and IFN-γ levels were confirmed as high, while IL-10 titers were low in the sera of reactional patients. Rs751271-GT genotype-bearing individuals correlated (p = 0.05) with lower levels of IL-6 in sera samples, corroborating the genetic results. Although the experimental size may be considered a limitation of the study, the findings confirm the association of classical variables such as sex and clinical forms with leprosy, demonstrating the consistency of the results. From the results, we conclude that SNPs at the NOD2 and IL6 genes are associated with leprosy reactions as an outcome. NOD2 also has a clear functional pro-inflammatory link that is coherent with the exacerbated responses observed in these patients.

Substrate-Coated Illumination Droplet Spray Ionization: Real-Time Monitoring of Photocatalytic Reactions

Science.gov (United States)

Zhang, Hong; Li, Na; Zhao, Dandan; Jiang, Jie; You, Hong

2017-09-01

Real-time monitoring of photocatalytic reactions facilitates the elucidation of the mechanisms of the reactions. However, suitable tools for real-time monitoring are lacking. Herein, a novel method based on droplet spray ionization named substrate-coated illumination droplet spray ionization (SCI-DSI) for direct analysis of photocatalytic reaction solution is reported. SCI-DSI addresses many of the analytical limitations of electrospray ionization (ESI) for analysis of photocatalytic-reaction intermediates, and has potential for both in situ analysis and real-time monitoring of photocatalytic reactions. In SCI-DSI-mass spectrometry (MS), a photocatalytic reaction occurs by loading sample solutions onto the substrate-coated cover slip and by applying UV light above the modified slip; one corner of this slip adjacent to the inlet of a mass spectrometer is the high-electric-field location for launching a charged-droplet spray. After both testing and optimizing the performance of SCI-DSI, the value of this method for in situ analysis and real-time monitoring of photocatalytic reactions was demonstrated by the removal of cyclophosphamide (CP) in TiO2/UV. Reaction times ranged from seconds to minutes, and the proposed reaction intermediates were captured and identified by tandem mass spectrometry. Moreover, the free hydroxyl radical (·OH) was identified as the main radicals for CP removal. These results show that SCI-DSI is suitable for in situ analysis and real-time monitoring of CP removal under TiO2-based photocatalytic reactions. SCI-DSI is also a potential tool for in situ analysis and real-time assessment of the roles of radicals during CP removal under TiO2-based photocatalytic reactions. Graphical Abstract[Figure not available: see fulltext.

Analysis of n+165Ho and 169Tm reactions

International Nuclear Information System (INIS)

Young, P.G.; Arthur, E.D.; Philis, C.; Nagel, P.; Collin, M.

1982-09-01

Experimental data for neutron-induced reactions on 165 Ho and 169 Tm have been theoretically analyzed in preparation for calculations on the unstable isotopes of Tm. A set of deformed optical model parameters was determined from measurements of s- and p-wave neutron strength functions, total cross sections, elastic angular distributions, and 16-MeV proton scattering to the 165 Ho ground and first excited states. The parameters for the 165 Ho and 169 Tm nuclei were linked by means of an isospin term in the real and imaginary well depths, together with adjustment of the ν 2 and ν 4 deformation parameters based on systematics in this mass region. Transmission coefficients from this analysis were used in Hauser-Feshbach statistical model calculations of the 169 Tm(n,ν) cross section as well as the 169 Tm(n,2n) and (n,3n) cross sections to 23 MeV, after application of suitable preequilibrium corrections. The results of these calculations are in good agreement with most of the available experimental data on 165 Ho and 169 Tm

Novel Chiral Bis-Phosphoramides as Organocatalysts for Tetrachlorosilane-Mediated Reactions

Directory of Open Access Journals (Sweden)

Sergio Rossi

2017-12-01

Full Text Available The formation of novel chiral bidentate phosphoroamides structures able to promote Lewis base-catalyzed Lewis acid-mediated reactions was investigated. Two different classes of phosphoroamides were synthetized: the first class presents a phthalic acid/primary diamine moiety, designed with the aim to perform a self-assembly recognition process through hydrogen bonds; the second one is characterized by the presence of two phosphoroamides as side arms connected to a central pyridine unit, able to chelate SiCl4 in a 2:1 adduct. These species were tested as organocatalysts in the stereoselective allylation of benzaldehyde and a few other aromatic aldehydes with allyl tributyltin in the presence of SiCl4 with good results. NMR studies confirm that only pyridine-based phosphoroamides effectively coordinate tetrachlorosilane and may lead to the generation of a self-assembled entity that would act as a promoter of the reaction. Although further work is necessary to clarify and confirm the formation of the hypothesized adduct, the study lays the foundation for the design and the synthesis of chiral supramolecular organocatalysts.

Low-energy nuclear reactions resulting as parametric interactions with similarity to K-shell electron capture

Energy Technology Data Exchange (ETDEWEB)

Hora, H. [University of New South Wales, Sydney 2052 (Australia); Miley, G.H. [Fusion Studies Laboratory, University of Illinois, Urbana, lL 61801 (United States); Li, X.Z. [Physics Department, Tsinghua University, Beijing 100084 (China); Kelly, J.C. [School of Physics, Sydney University, Sydney 2006 (Australia); Osman, F. [University of Western Sydney, Penrith-Soutti, NSW 1791 (Australia)

2006-07-01

Since the appeal by Brian Josephson at the meeting of the Nobel Laureates July 2004, it seems to be indicated to summarize the following serious, reproducible and confirmed observations on reactions of protons of deuterons incorporated in host metals such as palladium. Some reflections to Rutherford's discovery of nuclear physics, the Cockcroft Oliphant discovery of anomalous low-energy fusion reactions and the chemist Hahn's discovery of fission had to be included. Using gaseous atmosphere or discharges between palladium targets, rather significant results were seen e.g. from the 'life after death' heat production of such high values per host atom that only nuclear reactions can be involved. This supports the earlier evaluation of neutron generation in fully reversible experiments with gas discharges hinting that a reasonable screening effect - preferably in the swimming electron layer - may lead to reactions at nuclear distances d of pico-meters with reaction probability times U of about mega-seconds similar to the K-shell capture radioactivity. Further electrolytic experiments led to low-energy nuclear reactions (LENR) where the involvement of pollution could be excluded from the appearance of very seldom rare earth elements. A basically new theory for DD cross-sections is used to confirm the pico-meter- mega-second reactions of cold fusion. Other theoretical aspects are given from measured heavy element distributions similar to the standard abundance distribution, SAD, in the Universe with consequences on endothermic heavy nuclei generation, magic numbers and to quark-gluon plasmas. (authors)

Measurement and analysis of the reaction π-p→π-π+n at 63 GeV incident momentum

International Nuclear Information System (INIS)

Peters, S.C.A.

1980-01-01

The measurement and analysis of the reaction π - p→π - π + n at 63.2 GeV incident momentum is described. The aim of the experiment was to measure the s-dependence of the production mechanism and to search for high spin resonances in the ππ system. (Auth.)

Automatic NMR-based identification of chemical reaction types in mixtures of co-occurring reactions.

Science.gov (United States)

Latino, Diogo A R S; Aires-de-Sousa, João

2014-01-01

The combination of chemoinformatics approaches with NMR techniques and the increasing availability of data allow the resolution of problems far beyond the original application of NMR in structure elucidation/verification. The diversity of applications can range from process monitoring, metabolic profiling, authentication of products, to quality control. An application related to the automatic analysis of complex mixtures concerns mixtures of chemical reactions. We encoded mixtures of chemical reactions with the difference between the (1)H NMR spectra of the products and the reactants. All the signals arising from all the reactants of the co-occurring reactions were taken together (a simulated spectrum of the mixture of reactants) and the same was done for products. The difference spectrum is taken as the representation of the mixture of chemical reactions. A data set of 181 chemical reactions was used, each reaction manually assigned to one of 6 types. From this dataset, we simulated mixtures where two reactions of different types would occur simultaneously. Automatic learning methods were trained to classify the reactions occurring in a mixture from the (1)H NMR-based descriptor of the mixture. Unsupervised learning methods (self-organizing maps) produced a reasonable clustering of the mixtures by reaction type, and allowed the correct classification of 80% and 63% of the mixtures in two independent test sets of different similarity to the training set. With random forests (RF), the percentage of correct classifications was increased to 99% and 80% for the same test sets. The RF probability associated to the predictions yielded a robust indication of their reliability. This study demonstrates the possibility of applying machine learning methods to automatically identify types of co-occurring chemical reactions from NMR data. Using no explicit structural information about the reactions participants, reaction elucidation is performed without structure elucidation of

Automatic NMR-based identification of chemical reaction types in mixtures of co-occurring reactions.

Directory of Open Access Journals (Sweden)

Diogo A R S Latino

Full Text Available The combination of chemoinformatics approaches with NMR techniques and the increasing availability of data allow the resolution of problems far beyond the original application of NMR in structure elucidation/verification. The diversity of applications can range from process monitoring, metabolic profiling, authentication of products, to quality control. An application related to the automatic analysis of complex mixtures concerns mixtures of chemical reactions. We encoded mixtures of chemical reactions with the difference between the (1H NMR spectra of the products and the reactants. All the signals arising from all the reactants of the co-occurring reactions were taken together (a simulated spectrum of the mixture of reactants and the same was done for products. The difference spectrum is taken as the representation of the mixture of chemical reactions. A data set of 181 chemical reactions was used, each reaction manually assigned to one of 6 types. From this dataset, we simulated mixtures where two reactions of different types would occur simultaneously. Automatic learning methods were trained to classify the reactions occurring in a mixture from the (1H NMR-based descriptor of the mixture. Unsupervised learning methods (self-organizing maps produced a reasonable clustering of the mixtures by reaction type, and allowed the correct classification of 80% and 63% of the mixtures in two independent test sets of different similarity to the training set. With random forests (RF, the percentage of correct classifications was increased to 99% and 80% for the same test sets. The RF probability associated to the predictions yielded a robust indication of their reliability. This study demonstrates the possibility of applying machine learning methods to automatically identify types of co-occurring chemical reactions from NMR data. Using no explicit structural information about the reactions participants, reaction elucidation is performed without structure

Constant rate thermal analysis of a dehydrogenation reaction

Czech Academy of Sciences Publication Activity Database

Perejon, A.; Perez-Maqueda, L. A.; Sanchez-Jimenez, P.E.; Criado, J. M.; Murafa, Nataliya; Šubrt, Jan

2016-01-01

Roč. 6, č. 84 (2016), s. 81454-81460 ISSN 2046-2069 Institutional support: RVO:61388980 Keywords : solid-state reaction s * hydrogen storage properties * milled magnesium hydride Subject RIV: CA - Inorganic Chemistry Impact factor: 3.108, year: 2016

Tuberculin purified protein derivative (PPD) immunoassay as an in vitro alternative assay for identity and confirmation of potency.

Science.gov (United States)

Ho, Mei M; Kairo, Satnam K; Corbel, Michael J

2006-01-01

Tuberculin purified protein derivative (PPD) currently can only be standardised by delayed hypersensitivity skin reactions in sensitised guinea pigs. An in vitro dot blot immunoassay was developed for both identity and confirmation of potency estimation of PPD. Polyclonal antibodies (mainly IgG) were generated and immunoreacted with human, bovine and, to lesser extent, avian PPD preparations. Combining size exclusion chromatography (FPLC-SEC) and dot blot immunoassay, the results showed that PPD preparations were mixtures of very heterogeneous tuberculoproteins ranging in size from very large aggregates to very small degraded molecules. All individual fractions of PPD separated by size were immunoreactive, although those of the largest molecular sizes appeared the most immunoreactive in this in vitro dot blot immunoassay. This method is very sensitive and specific to tuberculoproteins and can be an in vitro alternative for the in vivo intradermal skin assay which uses guinea pigs for identity of PPD preparations. Although the capacity of PPD to elicit cell-mediated immune responses on intradermal testing has to be confirmed by in vivo assay, the dot blot immunoassay offers a rapid, sensitive and animal-free alternative to in vivo testing for confirming the identity of PPD preparations with appropriate potencies. This alternative assay would be particularly useful for national regulatory laboratories for confirming the data of manufacturers and thus reducing the use of animals.

FINANCIAL MARKET REACTIONS TO INTERNATIONAL MERGERS & ACQUISITIONS IN THE BREWING INDUSTRY: AN EVENT STUDY ANALYSIS

OpenAIRE

Heyder, Matthias; Ebneth, Oliver; Theuvsen, Ludwig

2008-01-01

Cross-border acquisitions have been the growing trend in recent years in the world brewing industry, giving brewers the opportunity to enhance their degree of internationalization and market share remarkably. This study employs event study analysis to examine 31 mergers and acquisitions among leading European brewing groups. Differences regarding financial market reactions can be determined within the European peer group. Managerial implications as well as future research propositions conclud...

Synthesis and reactions of C-phosphanylated thiazol-2-thiones.

Science.gov (United States)

Begum, I; Schnakenburg, G; Streubel, R

2016-02-21

The facile regioselective synthesis of the P(iii) substituted thiazol-2-thione 2 is presented. Reaction of 2 with hydrogenperoxide-urea, elemental sulfur and selenium resulted in P(v) chalcogenide thiazol-2-thiones 3-5. All compounds were characterized using (31)P, (1)H, (13)C NMR, IR and elemental analyses and, additionally, by the single-crystal X-ray diffraction technique. Oxidative desulfurization of the 5-phosphinoylated thiazol-2-thione 3 using hydrogenperoxide led to the first C-phosphanoyl substituted thiazolium salt (6). Deprotonation of 6 and in situ reaction with the cyclooctadiene rhodium(i) chloride dimer yielded thiazol-2-ylidene rhodium(i) complex 7 which was confirmed by NMR spectroscopy and ESI-MS spectrometry.

Pooled analysis of the CONFIRM Registries: outcomes in renal disease patients treated for peripheral arterial disease using orbital atherectomy.

Science.gov (United States)

Lee, Michael S; Yang, Tae; Adams, George L; Mustapha, Jihad; Das, Tony

2014-08-01

Patients with renal disease typically have severely calcified peripheral arterial disease. As a result, this population may have worse clinical outcomes following endovascular intervention compared to patients without renal insufficiency. Clinical trials typically exclude this patient population. Analysis of the CONFIRM I-III registries revealed 1105 patients with renal disease (1777 lesions) and 1969 patients without renal disease (2907 lesions) who underwent orbital atherectomy. This subanalysis compared the composite procedural complication rate including dissection, perforation, slow flow, vessel closure, spasm, embolism, and thrombus formation in patients with and without renal disease. Patients with renal disease had a higher prevalence of diabetes (Patherectomy resulted in similar low rates of procedural complications in the renal disease group compared with the non-renal disease group despite more unfavorable baseline clinical and lesion characteristics in the renal disease group.

Vibratory Reaction Unit for the Rapid Analysis of Proteins and Glycochains

Directory of Open Access Journals (Sweden)

Yukie Sasakura

2007-01-01

Full Text Available A protein digestion system using immobilized enzymes for protein identification and glycochain analyses has been developed, and a vibration reaction unit for micro-scale sample convection on an enzyme-immobilized solid surface was constructed. BSA as a model substrate was digested by this unit, and was successfully identified by mass spectrometry (MS analyses. Compared to the conventional liquid-phase digestion, the reaction unit increased the number of matched peptides from 9 to 26, protein score from 455 to 1247, and sequence coverage from 21% to 48%. Glycopeptidase F (NGF, an enzyme that cleaves N-glycans from glycoproteins, was also immobilized and used to remove the glycochains from human immunoglobulin G (IgG. Trypsin and NGF were immobilized on the same solid surface and used to remove glycochains from IgG in single-step. Glycochains were labeled with fluorescent reagent and analyzed by HPLC. Several peaks corresponding to the glycochains of IgG were detected. These results suggested that the single-step digestion system, by immobilized multiple enzymes (trypsin and NGF would be effective for the rapid structural analysis of glycoproteins.Abbreviations: BSA: bovine serum albumin; MS: mass spectrometry; NGF: glycopeptidase F; IgG: immunoglobulin G; PTM: post-translational modification; HPLC: high-performance liquid chromatography; PBS: phosphate-buffered saline; EDTA: ethylenediaminetetraacetic acid; DTT: dithiothreitol; RT: retention time; ABOE: p-aminobenzoic acid octyl ester; PDMS: polydimethylsiloxane; ArgC: endoprotease Arginine C.

Multipole decomposition analysis of the 27Al, 90Zr, 208Pb(p, n) reactions at 295 MeV

International Nuclear Information System (INIS)

Wakasa, T.; Greenfield, M.B.; Koori, N.; Okihana, A.; Hatanaka, K.

1996-01-01

Differential cross sections at θ lab between 0 and 15 and the polarization transfer D NN at zero degrees for the 27 Al, 90 Zr, 208 Pb(p,n) reactions are measured at a bombarding energy of 295 MeV. A multipole decomposition (MD) technique is applied to extract L=0, L=1, and L≥2 contributions to the cross sections. The summed Gamow-Teller strength B(GT) is compared with shell-model calculations for the 27 Al(p,n) and 90 Zr(p,n) reactions. The usefulness of the polarization transfer observable in the MD analysis is discussed. (orig.)

Study on reaction mechanism by analysis of kinetic energy spectra of light particles and formation of final products

Science.gov (United States)

Giardina, G.; Mandaglio, G.; Nasirov, A. K.; Anastasi, A.; Curciarello, F.; Fazio, G.

2018-05-01

The sensitivity of reaction mechanism in the formation of compound nucleus (CN) by the analysis of kinetic energy spectra of light particles and of reaction products are shown. The dependence of the P CN fusion probability of reactants and W sur survival probability of CN against fission at its deexcitation on the mass and charge symmetries in the entrance channel of heavy-ion collisions, as well as on the neutron numbers is discussed. The possibility of conducting a complex program of investigations of the complete fusion by reliable ways depends on the detailed and refined methods of experimental and theoretical analyses.

Synthesis of Citric-Acrylate Oligomer and its in-Situ Reaction with Chrome Tanned Collagen (hide powder)

International Nuclear Information System (INIS)

Haroun, A.A.; Masoud, R.A.; Bronco, S.; Ciardelli, F.

2005-01-01

The purpose of this study was to formulate the new combined system of acrylic and citric acids, which has been prepared by free radical polymerization and esterification reaction at the same time to form citric acrylate (CAC) oligomer through ester linkage and low molecular weight (Mw 2241), in compared with polyacrylic acid. The chemical structure and the reaction mechanism of this oligomer were confirmed by different spectroscopic tools (1 H , 13 C-NMR, ATR-IR), gel permeation chromatography and thermogravimetric analysis (TGA/DTA). The problem of the effect of the masking agents in the chrome tanning of the collagen and the pickling of the hide has been approached from the study of the hydrothermal and mechanical properties, using this new eco-friendly oligomer, which was carried out in-situ treated/grafted chrome tanned collagen (hide powder), and pickled hide. The microemulsion grafting copolymerization of (CAC) using 2.2-azo-bis isobutyronitrile (ABIN), via direct coupling reaction, onto the chrome tanned collagen showed that the free amino groups of the collagen were considered to be a potential site for the in-situ reaction with (CAC) oligomer. Also, using of citric-acrylate (CAC) oligomer, during chrome tanning of leather, instead of the traditional strong acids (sulfuric, hydrochloric and formic) resulted in significant improvement in chrome exhaustion and physical properties

Scrapping of student bursaries confirmed.

Science.gov (United States)

Longhurst, Chris

2016-07-27

Student bursaries for nurses will be scrapped from next year, the government has confirmed. Undergraduate nursing and midwifery students in England will now face tuition fees and student loans from August 2017.

Unimolecular and collisionally induced ion reactions

International Nuclear Information System (INIS)

Beynon, J.H.; Boyd, R.K.

1978-01-01

The subject is reviewed under the following headings: introduction (mass spectroscopy and the study of fragmentation reactions of gaseous positive ions); techniques and methods (ion sources, detection systems, analysis of ions, data reduction); collision-induced reactions of ions and unimolecular fragmentations of metastable ions; applications (ion structure, energetic measurements, analytical applications, other applications). 305 references. (U.K.)

Supramolecular hydrogel formation between chitosan and hydroxypropyl β-cyclodextrin via Diels-Alder reaction and its drug delivery.

Science.gov (United States)

Zhang, Mengke; Wang, Jinpeng; Jin, Zhengyu

2018-07-15

Chitosan-cyclodextrin hydrogel (CFCD) was prepared via Diels-Alder reaction between furfural functionalized chitosan (CF) and N-maleoyl alanine functionalized hydroxypropyl β-cyclodextrin (HPCD-AMI) in aqueous media without any catalyst or initiator. The CF and HPCD-AMI were confirmed by Fourier transform infrared spectroscopy and 1 H nuclear magnetic resonance spectroscopy. The resultant CFCD hydrogel was characterized in terms of thermal peripteries, microstructure, rheology behavior, and swelling capacity. The rheology analysis found that the storage modulus G' ranged from 1pa to 1200pa as the degree of furfural substitute on chitosan increased from 2.6% to 28.3%, indicating the hydrogel strength can be tuned readily by reaction stoichiometry. The swelling behaviors proved that CFCD hydrogel was pH-responsive with low swelling capacity, which would be preferable for drug delivery. Drug adsorption analysis showed the introduction of cyclodextrin into CFCD hydrogels promoted drug adsorption capacity. In addition, methyl orange cumulative release in PBS buffer was only 48.85% after 24h, suggesting CFCD hydrogel had good sustained release capacity on the loaded drug. Copyright © 2018 Elsevier B.V. All rights reserved.

Simultaneous Nuclear Reaction Analysis of Boron and Phosphorus in Thin Borophosphosilicate Glass Films Using (α,p) Reactions

International Nuclear Information System (INIS)

Walsh, D.S.; Doyle, B.L.

1999-01-01

A method combining (α,p) NRA and ellipsometry has been developed for measuring the Boron and Phosphorus content of borophosphosilicate glass (BPSG) used for interlevel dielectrics in integrated circuits. Yields from the 31 P(α,p 0 ) 34 S (Q = 0.63 MeV) and 10 B(α,p 0 ) 13 C (Q = 4.06 MeV) reactions are coupled with ellipsometry thickness measurements to calculate the average atomic percent of B and P in the film. Due to the relatively low Q value of the 31 P(α,p 0 ) 34 S reaction and the thickness range of the glass films (le 1.2 micrometers) they analyze, fairly high energy alpha particles, and Mylar range foils on the detector are required. Alpha energy, detector angle and range foil thickness were determined by reaction yields and the need to separate the yield peaks of interest from competing (α,p) reactions and backscattered alphas. They have determined that 6.0 MeV incident alphas with a detector angle of 135degree and about 100 micrometers of Mylar range foil are optimum for the system. The yield for the 10 B(α,p 0 ) 13 C reaction is quite constant in the energy range of interest (approximately 5.8 to 6 MeV) but the yield for the 31 P(α,p 0 ) 34 S is not. Consequently, a simple conversion from standard BPSG reference samples (independently quantified by ICP mass spectrometry) is adequate to calculate a film's %B content. The %P calculation is more complex, involving a three-dimensional fit of the P yield data and measured film thickness to the film %P content. This fit is based upon yield data from a matrix of standard film samples. The technique is sensitive to 0.1% with an accuracy of ±3 to ±10% depending on the sample. This measurement method is used routinely at Sandia National Laboratories in support of their fabrication process lines

Reaction list for charged-particle-induced nuclear reactions: Z = 1 to Z = 98 (H to Cf), July 1973--September 1974

International Nuclear Information System (INIS)

McGowan, F.K.; Milner, W.T.

1975-01-01

This Reaction List for charged-particle-induced nuclear reactions has been prepared from the journal literature for the period from July 1973 through September 1974. Each published experimental paper is listed under the target nucleus in the nuclear reaction with a brief statement of the type of data in the paper. The nuclear reaction is denoted by A(a,b)B, where the mass of a is greater than or equal to (one nucleon mass). There is no restriction on energy. Nuclear reactions involving mesons in the outgoing channel are not included. Theoretical papers which treat directly with the analysis of nuclear reaction data and results are included in the Reaction List. The cutoff date for literature was September 30, 1974. (U.S.)

Combined steam and carbon dioxide reforming of methane and side reactions: Thermodynamic equilibrium analysis and experimental application

International Nuclear Information System (INIS)

Jang, Won-Jun; Jeong, Dae-Woon; Shim, Jae-Oh; Kim, Hak-Min; Roh, Hyun-Seog; Son, In Hyuk; Lee, Seung Jae

2016-01-01

Highlights: • Selected variables have a significant influence on yields of synthesis gas. • (CO_2 + H_2O)/CH_4 affects the temperature which can achieve the maximum conversion. • Coke is formed at low temperatures even with excess oxidizing agent. • The occurrence of RWGS becomes critical in real chemical reactions. • Equilibrium conversions are maintained for 500 h without detectable deactivation. - Abstract: Thermodynamic equilibrium analysis of the combined steam and carbon dioxide reforming of methane (CSCRM) and side reactions was performed using total Gibbs free energy minimization. The effects of (CO_2 + H_2O)/CH_4 ratio (0.9–2.9), CO_2:H_2O ratio (3:1–1:3), and temperature (500–1000 °C) on the equilibrium conversions, yields, coke yield, and H_2/CO ratio were investigated. A (CO_2 + H_2O)/CH_4 ratio greater than 1.2, a CO_2:H_2O ratio of 1:2.1, and a temperature of at least 850 °C are preferable reaction conditions for the synthesis gas preparation in the gas to liquid process. Simulated conditions were applied to the CSCRM reaction and the experimental data were compared with the thermodynamic equilibrium results. The thermodynamic equilibrium results were mostly consistent with the experimental data, but the reverse water gas shift reaction rapidly occurred in the real chemical reaction and under excess oxidizing agent conditions. In addition, a long-term stability test (under simulated conditions) showed that the equilibrium conversion was maintained for 500 h and that the coke formation on the used catalyst was not observed.

Compilation and R-matrix analysis of Big Bang nuclear reaction rates

International Nuclear Information System (INIS)

Descouvemont, Pierre; Adahchour, Abderrahim; Angulo, Carmen; Coc, Alain; Vangioni-Flam, Elisabeth

2004-01-01

We use the R-matrix theory to fit low-energy data on nuclear reactions involved in Big Bang nucleosynthesis. Special attention is paid to the rate uncertainties which are evaluated on statistical grounds. We provide S factors and reaction rates in tabular and graphical formats

O-Methylisourea Can React with the α-Amino Group of Lysine: Implications for the Analysis of Reactive Lysine.

Science.gov (United States)

Hulshof, Tetske G; Rutherfurd, Shane M; Sforza, Stefano; Bikker, Paul; van der Poel, Antonius F B; Hendriks, Wouter H

2017-02-01

The specificity of O-methylisourea (OMIU) to bind to the ε-amino group of Lys, an important supposition for the OMIU-reactive Lys analysis of foods, feeds, ingredients, and digesta, was investigated. Crystalline l-Lys incubated under standard conditions with OMIU resulted in low homoarginine recoveries. The reaction of OMIU with the α-amino group of Lys was confirmed by MS analysis, with double derivatized Lys being identified. None of the changes in reaction conditions (OMIU pH, OMIU to Lys ratio, and reaction time) with crystalline l-Lys resulted in 100% recovery of homoarginine. The average free Lys content in ileal digesta of growing pigs and broilers was found to be 13% of total Lys, which could result in a significant underestimation of the reactive Lys content. The reaction of OMIU with α-amino groups may necessitate analysis of free Lys to accurately quantify reactive lysine in samples containing a large proportion of Lys with a free α-amino group.

Mechanistic Insight into the Dehydro-Diels-Alder Reaction of Styrene-Ynes.

Science.gov (United States)

Kocsis, Laura S; Kagalwala, Husain N; Mutto, Sharlene; Godugu, Bhaskar; Bernhard, Stefan; Tantillo, Dean J; Brummond, Kay M

2015-12-04

The Diels-Alder reaction represents one of the most thoroughly studied and well-understood synthetic transformations for the assembly of six-membered rings. Although intramolecular dehydro-Diels-Alder (IMDDA) reactions have previously been employed for the preparation of naphthalene and dihydronaphthalene substrates, low yields and product mixtures have reduced the impact and scope of this reaction. Through the mechanistic studies described within, we have confirmed that the thermal IMDDA reaction of styrene-ynes produces a naphthalene product via loss of hydrogen gas from the initially formed cycloadduct, a tetraenyl intermediate. Alternatively, the dihydronaphthalene product is afforded from the same tetraenyl intermediate via a radical isomerization process. Moreover, we have identified conditions that can be used to achieve efficient, high-yielding, and selective IMDDA reactions of styrene-ynes to form either naphthalene or dihydronaphthalene products. The operational simplicity and retrosynthetic orthogonality of this method for the preparation of naphthalenes and dihydronaphthalenes makes this transformation appealing for the synthesis of medicinal and material targets. The mechanistic studies within may impact the development of other thermal transformations.

Effect of magnetic field on the zero valent iron induced oxidation reaction

International Nuclear Information System (INIS)

Kim, Dong-hyo; Kim, Jungwon; Choi, Wonyong

2011-01-01

Highlights: → We investigate the zero valent iron induced oxidation in the presence of magnetic field. → The oxidative degradation of 4-chlorophenol is enhanced by the magnetic field. → ESR measurement confirms that more OH radicals are generated in the presence of magnetic field. → The magnetic field affects the mass transfer of O 2 and the recombination of radicals. - Abstract: The magnetic field (MF) effect on the zero valent iron (ZVI) induced oxidative reaction was investigated for the first time. The degradation of 4-chlorophenol (4-CP) in the ZVI system was employed as the test oxidative reaction. MF markedly enhanced the degradation of 4-CP with the concurrent production of chlorides. The consumption of dissolved O 2 by ZVI reaction was also enhanced in the presence of MF whereas the competing reaction of H 2 production from proton reduction was retarded. Since the ZVI-induced oxidation is mainly driven by the in situ generated hydroxyl radicals, the production of OH radicals was monitored by the spin trap method using electron spin resonance (ESR) spectroscopy. It was confirmed that the concentration of trapped OH radicals was enhanced in the presence of MF. Since both O 2 and Fe 0 are paramagnetic, the diffusion of O 2 onto the iron surface might be accelerated under MF. The magnetized iron can attract oxygen on itself, which makes the mass transfer process faster. As a result, the surface electrochemical reaction between Fe 0 and O 2 can be accelerated with the enhanced production of OH radicals. MF might retard the recombination of OH radicals as well.

Kinematic relations in heavy-ion reactions

International Nuclear Information System (INIS)

Gippner, P.; Kalpakchieva, R.

1988-01-01

The present work gives a short overview of the non-relativistic kinematics of nuclear reactions derived on the basis of the conservation laws of energy and linear momentum. Section 2 contains kinematic relations valid for two-body reactions, sections 3 makes use of these relations to describe sequential fission as a special case of reactions with three particles in the exit channel. It is the aim of this work to comprise the kinematic formulae essential for planning of experiments, data analysis and critical examination of the obtained results. (author)

Continuum spectra in light-ion reactions

Energy Technology Data Exchange (ETDEWEB)

Tamura, T.; Udagawa, T. [Texas Univ., Austin (USA). Dept. of Physics; Ikegami, H.; Muraoka, M [eds.

1980-01-01

Recent developments in the use of multi-step direct reaction method, to fit continuum cross sections of light-ion reactions, are reviewed. There has been a long-standing difficulty in reproducing sufficiently large (p, p') continuum cross section, but it has now been all but removed. It will be discussed in some detail, how this was achieved. Analyses of very recent data on analyzing powers in the continuum of (p, p') and (p, ..cap alpha..) reactions will also be discussed. Finally, analysis of the breakup of h into d and p will be presented.

Nanoscale studies of cement chemistry with {sup 15}N resonance reaction analysis

Energy Technology Data Exchange (ETDEWEB)

Schweitzer, Jeffrey S. [University of Connecticut, Department of Physics, Unit 3046, Storrs, CT 06269-3046 (United States)]. E-mail: schweitz@phys.uconn.edu; Livingston, Richard A. [Federal Highway Administration, HRDI-05, 6300 Georgetown Pike McLean, VA 22101 (United States); Rolfs, Claus [Institut fuer Physik mit Ionenstrahlen, Ruhr-Universitaet, Bochum Universitaetsstr. 150, Gebaeude NB 3, 44780 Bochum (Germany); Becker, Hans-Werner [Institut fuer Physik mit Ionenstrahlen, Ruhr-Universitaet, Bochum Universitaetsstr. 150, Gebaeude NB 3, 44780 Bochum (Germany); Kubsky, Stefan [Institut fuer Physik mit Ionenstrahlen, Ruhr-Universitaet, Bochum Universitaetsstr. 150, Gebaeude NB 3, 44780 Bochum (Germany); Spillane, Timothy [University of Connecticut, Department of Physics, Unit 3046, Storrs, CT 06269-3046 (United States); Castellote, Marta [Institute of Construction Science ' Eduardo Torroja' (CSIC), Serrano Galvache no. 4, 28033 Madrid (Spain); Viedma, Paloma G. de [Institute of Construction Science ' Eduardo Torroja' (CSIC), Serrano Galvache no. 4, 28033 Madrid (Spain)

2005-12-15

Analyses of materials with ion beams have proven to be a valuable technique for describing the spatial distributions of specific elements in host materials. We have applied this technique using the {sup 15}N(p, {alpha}{gamma}){sup 12}C reaction to study the time dependence of the chemical reactions involved in the curing of cement. By using the Dynamitron Tandem accelerator at the Ruhr Universitaet, Bochum, Germany, we have been able to achieve a few nanometer spatial resolution at the surface of cement grains and to study the hydrogen distributions to a depth of about 2 {mu}m. By applying a technique for stopping the chemical reactions at arbitrary times, the time dependence of the chemical reactions involving specific components of cement can be investigated. In addition, the effects of additives on the chemical reactions have been studied, as have materials that are components of concrete.

Cross-cultural analysis of teacher confirmation, student motivation, classroom emotion and emotional interest in China, Korea and Japan

OpenAIRE

Shen, Tingting

2016-01-01

This study investigates the relationship between teacher confirmation and student motivation across three cultures: China, Korea, and Japan and studies how classroom emotion and emotional interest influence this relationship in three different countries. Students in China (n=718), Korea (n=362), and Japan (n=350) completed questionnaires assessing their perceived teacher confirmation, student motivation, classroom emotion and emotional interest. Results of these samples indicate that teacher ...

Induction and Confirmation Theory: An Approach based on a Paraconsistent Nonmonotonic Logic

Directory of Open Access Journals (Sweden)

Ricardo Sousa Silvestre

2010-12-01

Full Text Available This paper is an effort to realize and explore the connections that exist between nonmonotonic logic and confirmation theory. We pick up one of the most wide-spread nonmonotonic formalisms – default logic – and analyze to what extent and under what adjustments it could work as a logic of induction in the philosophical sense. By making use of this analysis, we extend default logic so as to make it able to minimally perform the task of a logic of induction, having as a result a system which we believe has interesting properties from the standpoint of theory of confirmation. It is for instance able to represent chains of inductive rules as well as to reason paraconsistently on the conclusions obtained from them. We then use this logic to represent some traditional ideas concerning confirmation theory, in particular the ones proposed by Carl Hempel in his classical paper “Studies in the Logic of Confirmation” of 1945 and the ones incorporated in the so-called abductive and hy-pothetico-deductive models.

α -induced reactions on 115In: Cross section measurements and statistical model analysis

Science.gov (United States)

Kiss, G. G.; Szücs, T.; Mohr, P.; Török, Zs.; Huszánk, R.; Gyürky, Gy.; Fülöp, Zs.

2018-05-01

Background: α -nucleus optical potentials are basic ingredients of statistical model calculations used in nucleosynthesis simulations. While the nucleon+nucleus optical potential is fairly well known, for the α +nucleus optical potential several different parameter sets exist and large deviations, reaching sometimes even an order of magnitude, are found between the cross section predictions calculated using different parameter sets. Purpose: A measurement of the radiative α -capture and the α -induced reaction cross sections on the nucleus 115In at low energies allows a stringent test of statistical model predictions. Since experimental data are scarce in this mass region, this measurement can be an important input to test the global applicability of α +nucleus optical model potentials and further ingredients of the statistical model. Methods: The reaction cross sections were measured by means of the activation method. The produced activities were determined by off-line detection of the γ rays and characteristic x rays emitted during the electron capture decay of the produced Sb isotopes. The 115In(α ,γ )119Sb and 115In(α ,n )Sb118m reaction cross sections were measured between Ec .m .=8.83 and 15.58 MeV, and the 115In(α ,n )Sb118g reaction was studied between Ec .m .=11.10 and 15.58 MeV. The theoretical analysis was performed within the statistical model. Results: The simultaneous measurement of the (α ,γ ) and (α ,n ) cross sections allowed us to determine a best-fit combination of all parameters for the statistical model. The α +nucleus optical potential is identified as the most important input for the statistical model. The best fit is obtained for the new Atomki-V1 potential, and good reproduction of the experimental data is also achieved for the first version of the Demetriou potentials and the simple McFadden-Satchler potential. The nucleon optical potential, the γ -ray strength function, and the level density parametrization are also

Kinetics Analysis of Synthesis Reaction of Struvite With Air-Flow Continous Vertical Reactors

Science.gov (United States)

Edahwati, L.; Sutiyono, S.; Muryanto, S.; Jamari, J.; Bayuseno, dan A. P.

2018-01-01

Kinetics reaction is a knowledge about a rate of chemical reaction. The differential of the reaction rate can be determined from the reactant material or the formed material. The reaction mechanism of a reactor may include a stage of reaction occurring sequentially during the process of converting the reactants into products. In the determination of reaction kinetics, the order of reaction and the rate constant reaction must be recognized. This study was carried out using air as a stirrer as a medium in the vertical reactor for crystallization of struvite. Stirring is one of the important aspects in struvite crystallization process. Struvite crystals or magnesium ammonium phosphate hexahydrates (MgNH4PO4·6H2O) is commonly formed in reversible reactions and can be generated as an orthorhombic crystal. Air is selected as a stirrer on the existing flow pattern in the reactor determining the reaction kinetics of the crystal from the solution. The experimental study was conducted by mixing an equimolar solution of 0.03 M NH4OH, MgCl2 and H3PO4 with a ratio of 1: 1: 1. The crystallization process of the mixed solution was observed in an inside reactor at the flow rate ranges of 16-38 ml/min and the temperature of 30°C was selected in the study. The air inlet rate was kept constant at 0.25 liters/min. The pH solution was adjusted to be 8, 9 and 10 by dropping wisely of 1 N KOH solution. The crystallization kinetics was examined until the steady state of the reaction was reached. The precipitates were filtered and dried at a temperature for subsequent material characterization, including Scanning Electron Microscope (SEM) and XRD (X-Ray diffraction) method. The results show that higher flow rate leads to less mass of struvite.

Real-time polymerase chain reaction for diagnosing infectious mononucleosis in pediatric patients: A systematic review and meta-analysis.

Science.gov (United States)

Jiang, Sha-Yi; Yang, Jing-Wei; Shao, Jing-Bo; Liao, Xue-Lian; Lu, Zheng-Hua; Jiang, Hui

2016-05-01

In this meta-analysis, we evaluated the diagnostic role of Epstein-Barr virus deoxyribonucleic acid detection and quantitation in the serum of pediatric and young adult patients with infectious mononucleosis. The primary outcome of this meta-analysis was the sensitivity and specificity of Epstein-Barr virus (EBV) deoxyribonucleic acid (DNA) detection and quantitation using polymerase chain reaction (PCR). A systematic review and meta-analysis was performed by searching for articles that were published through September 24, 2014 in the following databases: Medline, Cochrane, EMBASE, and Google Scholar. The following keywords were used for the search: "Epstein-Barr virus," "infectious mononucleosis," "children/young adults/infant/pediatric," and "polymerase chain reaction or PCR." Three were included in this analysis. We found that for detection by PCR, the pooled sensitivity for detecting EBV DNA was 77% (95%CI, 66-86%) and the pooled specificity for was 98% (95%CI, 93-100%). Our findings indicate that this PCR-based assay has high specificity and good sensitivity for detecting of EBV DNA, indicating it may useful for identifying patients with infectious mononucleosis. This assay may also be helpful to identify young athletic patients or highly physically active pediatric patients who are at risk for a splenic rupture due to acute infectious mononucleosis. © 2015 Wiley Periodicals, Inc.

Modeling chemical reactions for drug design.

Science.gov (United States)

Gasteiger, Johann

2007-01-01

Chemical reactions are involved at many stages of the drug design process. This starts with the analysis of biochemical pathways that are controlled by enzymes that might be downregulated in certain diseases. In the lead discovery and lead optimization process compounds have to be synthesized in order to test them for their biological activity. And finally, the metabolism of a drug has to be established. A better understanding of chemical reactions could strongly help in making the drug design process more efficient. We have developed methods for quantifying the concepts an organic chemist is using in rationalizing reaction mechanisms. These methods allow a comprehensive modeling of chemical reactivity and thus are applicable to a wide variety of chemical reactions, from gas phase reactions to biochemical pathways. They are empirical in nature and therefore allow the rapid processing of large sets of structures and reactions. We will show here how methods have been developed for the prediction of acidity values and of the regioselectivity in organic reactions, for designing the synthesis of organic molecules and of combinatorial libraries, and for furthering our understanding of enzyme-catalyzed reactions and of the metabolism of drugs.

Selective enrichment of volatiles confirmed

Science.gov (United States)

de Pater, Imke

2018-05-01

Hydrogen sulfide gas is detected above Uranus's main cloud deck, confirming the prevalence of H2S ice particles as the main cloud component and a strongly unbalanced nitrogen/sulfur ratio in the planet's deep atmosphere.

A case of leucism in the burrowing owl Athene cunicularia (Aves: Strigiformes with confirmation of species identity using cytogenetic analysis

Directory of Open Access Journals (Sweden)

Denise M Nogueira

2011-02-01

Full Text Available Leucism is an inherited disorder, characterized by the lack of pigments in part or all of the body, normal coloration of the eyes and, in birds, in naked parts such as the bill and legs. This kind of disorder is sometimes erroneously designated as albinism or partial albinism. In this study, we present a case of leucism in a wild owl. The studied individual presented completely white plumage, light-yellow coloration of legs and bill and normal coloration of eyes. According to morphological features, this owl is a specimen of burrowing owl, Athene cunicularia (Molina, 1782. To confirm the species identity, we used cytogenetic analyses for karyotypic determination, comparing it to the previously described one in the literature. We also studied a captive female of A. cunicularia to complement the species karyotype, which was described in the literature based only on a single male. The karyotype of the leucistic owl individual was compatible with the previously published one for A. cunicularia, confirming the bird was a male specimen. Cytogenetic analysis of the captive female showed that the W sex chromosome is metacentric and comparable to the seventh pair in size. This is the first description of a case of leucism in A. cunicularia for South America. Long-term studies are needed in the Neotropical region to evaluate survival and breeding success in leucistic birds.

Continuous-flow retro-Diels-Alder reaction: an efficient method for the preparation of pyrimidinone derivatives.

Science.gov (United States)

Nekkaa, Imane; Palkó, Márta; Mándity, István M; Fülöp, Ferenc

2018-01-01

The syntheses of various pyrimidinones as potentially bioactive products by means of the highly controlled continuous-flow retro-Diels-Alder reaction of condensed pyrimidinone derivatives are presented. Noteworthy, the use of this approach allowed us to rapidly screen a selection of conditions and quickly confirm the viability of preparing the desired pyrimidinones in short reaction times. Yields typically higher than those published earlier using conventional batch or microwave processes were achieved.

Study of reactions for the obtention of uranium tetrafluoride and hexafluoride

International Nuclear Information System (INIS)

Guzella, M.F.R.

1984-01-01

Based on an exhaustive bibliographical review, the main production processes of uranium hexafluoride in pilot plants and industrial facilities are described. The known reactions, confirmed in laboratory experiments, that lead to UF 6 or other intermediate fluorides, are presented and discussed. In order to determine a new thermodinamically feasible reaction involving the sulfur hexafluoride as fluorinating agent, a mock-up facility was designed and constructed as part of the R and D work planned at CDTN (NUCLEBRAS Center for Nuclear Technology Development, MG - Brazil). For the UF 4 synthesis employing U 3 O 8 and SF 6 , several experimental parameters were studied. The reaction time, gas flow, temperature and stoichiometric relations among reagents are described in detail. Suggestions for further investigations regarding this new reagent are made. (Author) [pt

Typewriting rate as a function of reaction time.

Science.gov (United States)

Hayes, V; Wilson, G D; Schafer, R L

1977-12-01

This study was designed to determine the relationship between reaction time and typewriting rate. Subjects were 24 typists ranging in age from 19 to 39 yr. Reaction times (.001 sec) to a light were recorded for each finger and to each alphabetic character and three punctuation marks. Analysis of variance yielded significant differences in reaction time among subjects and fingers. Correlation between typewriting rate and average reaction time to the alphabetic characters and three punctuation marks was --.75. Correlation between typewriting rate and the difference between the reaction time of the hands was --.42. Factors influencing typewriting rate may include reaction time of the fingers, difference between the reaction time of the hands, and reaction time to individual keys on the typewriter. Implications exist for instructional methodology and further research.

Evaluation of the LTQ-Orbitrap mass spectrometer for the analysis of polymerase chain reaction products.

Science.gov (United States)