NASA Astrophysics Data System (ADS)
Bruggeman, M.; Baeten, P.; De Boeck, W.; Carchon, R.
1996-02-01
Neutron coincidence counting is commonly used for the non-destructive assay of plutonium bearing waste or for safeguards verification measurements. A major drawback of conventional coincidence counting is related to the fact that a valid calibration is needed to convert a neutron coincidence count rate to a 240Pu equivalent mass ( 240Pu eq). In waste assay, calibrations are made for representative waste matrices and source distributions. The actual waste however may have quite different matrices and source distributions compared to the calibration samples. This often results in a bias of the assay result. This paper presents a new neutron multiplicity sensitive coincidence counting technique including an auto-calibration of the neutron detection efficiency. The coincidence counting principle is based on the recording of one- and two-dimensional Rossi-alpha distributions triggered respectively by pulse pairs and by pulse triplets. Rossi-alpha distributions allow an easy discrimination between real and accidental coincidences and are aimed at being measured by a PC-based fast time interval analyser. The Rossi-alpha distributions can be easily expressed in terms of a limited number of factorial moments of the neutron multiplicity distributions. The presented technique allows an unbiased measurement of the 240Pu eq mass. The presented theory—which will be indicated as Time Interval Analysis (TIA)—is complementary to Time Correlation Analysis (TCA) theories which were developed in the past, but is from the theoretical point of view much simpler and allows a straightforward calculation of deadtime corrections and error propagation. Analytical expressions are derived for the Rossi-alpha distributions as a function of the factorial moments of the efficiency dependent multiplicity distributions. The validity of the proposed theory is demonstrated and verified via Monte Carlo simulations of pulse trains and the subsequent analysis of the simulated data.
Characterizations of double pulsing in neutron multiplicity and coincidence counting systems
Koehler, Katrina E.; Henzl, Vladimir; Croft, Stephen; ...
2016-06-29
Passive neutron coincidence/multiplicity counters are subject to non-ideal behavior, such as double pulsing and dead time. It has been shown in the past that double-pulsing exhibits a distinct signature in a Rossi-alpha distribution, which is not readily noticed using traditional Multiplicity Shift Register analysis. But, it has been assumed that the use of a pre-delay in shift register analysis removes any effects of double pulsing. Here, we use high-fidelity simulations accompanied by experimental measurements to study the effects of double pulsing on multiplicity rates. By exploiting the information from the double pulsing signature peak observable in the Rossi-alpha distribution, themore » double pulsing fraction can be determined. Algebraic correction factors for the multiplicity rates in terms of the double pulsing fraction have been developed. We also discuss the role of these corrections across a range of scenarios.« less
Nuclear instrumentation in VENUS-F
NASA Astrophysics Data System (ADS)
Wagemans, J.; Borms, L.; Kochetkov, A.; Krása, A.; Van Grieken, C.; Vittiglio, G.
2018-01-01
VENUS-F is a fast zero power reactor with 30 wt% U fuel and Pb/Bi as a coolant simulator. Depending on the experimental configuration, various neutron spectra (fast, epithermal, and thermal islands) are present. This paper gives a review of the nuclear instrumentation that is applied for reactor control and in a large variety of physics experiments. Activation foils and fission chambers are used to measure spatial neutron flux profiles, spectrum indices, reactivity effects (with positive period and compensation method or the MSM method) and kinetic parameters (with the Rossi-alpha method). Fission chamber calibrations are performed in the standard irradiation fields of the BR1 reactor (prompt fission neutron spectrum and Maxwellian thermal neutron spectrum).
Neutron noise measurements at the Delphi subcritical assembly
DOE Office of Scientific and Technical Information (OSTI.GOV)
Szieberth, M.; Klujber, G.; Kloosterman, J. L.
2012-07-01
The paper presents the results and evaluations of a comprehensive set of neutron noise measurements on the Delphi subcritical assembly of the Delft Univ. of Technology. The measurements investigated the effect of different source distributions (inherent spontaneous fission and {sup 252}Cf) and the position of the detectors applied (both radially and vertically). The evaluation of the measured data has been performed by the variance-to-mean ratio (VTMR, Feynman-{alpha}), the autocorrelation (ACF, Rossi-{alpha}) and the cross-correlation (CCF) methods. The values obtained for the prompt decay constant show a strong bias, which depends both on the detector position and on the source distribution.more » This is due to the presence of higher modes in the system. It has been observed that the {alpha} value fitted is higher when the detector is close to the boundary of the core or to the {sup 252}Cf point-source. The higher alpha-modes have also been observed by fitting functions describing two alpha-modes. The successful set of measurement also provides a good basis for further theoretical investigations including the Monte Carlo simulation of the noise measurements and the calculation of the alpha-modes in the Delphi subcritical assembly. (authors)« less
Baeten; Bruggeman; Paepen; Carchon
2000-03-01
The non-destructive quantification of transuranic elements in nuclear waste management or in safeguards verifications is commonly performed by passive neutron assay techniques. To minimise the number of unknown sample-dependent parameters, Neutron Multiplicity Counting (NMC) is applied. We developed a new NMC-technique, called Time Interval Correlation Spectroscopy (TICS), which is based on the measurement of Rossi-alpha time interval distributions. Compared to other NMC-techniques, TICS offers several advantages.
Reactivity measurements using the Zolotukhin-Mogilner Method
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
2015-07-01
The zero count probability method (also called Zolotukhin-Mogilner Method, after its inventors) is a method for measuring the reactivity in nuclear reactors, being a competitor of the [more well-known in the West] Feynman-alpha Method and the Rossi-alpha Method. The modus operandi of this method is using the detector channels where there was no counting at all in order to calculate reactor parameters. In deep subcriticality few models have been tested and this work tries out the Zolotukhin-Mogilner Method in one of such scenarios: measurements will be made in environments below -3,5 k pcm in the zero-potency water-moderated reactor IPEN/MB-01 whichmore » is fuelled by UO{sub 2} enriched by 4.3%. These extremely low reactivity environments are required because the chance of no counts on the detector must be significant: otherwise, the method would demand a large time of acquisition of data. Besides that, the method is very simple and straightforward. One of the advantages of this method is that it needs very little data reduction, since the essential data is directly given by the measuring apparatus. The detection will be in charge of modern BF{sub 3} detectors. It will be assumed that, in these deep subcritical systems, the function K{sub eff} = f(N-Nkp) has a linear portion in its first part, resulting of the decomposition of it in a Taylor series. The value of alpha is related to the reactivity ρ with linear dependency. The results will be compared with recent studies of the two main methods described above. Presented for the first time in the 60's, this tool has seen little use in the west hemisphere. This work shows its use in the measurements of the nuclear reactor IPEN/MB-01, as well as the code developed for its employment. It will be the first time this method is used in the south hemisphere. (authors)« less
Advances in the computation of the Sjöstrand, Rossi, and Feynman distributions
Talamo, A.; Gohar, Y.; Gabrielli, F.; ...
2017-02-01
This study illustrates recent computational advances in the application of the Sjöstrand (area), Rossi, and Feynman methods to estimate the effective multiplication factor of a subcritical system driven by an external neutron source. The methodologies introduced in this study have been validated with the experimental results from the KUKA facility of Japan by Monte Carlo (MCNP6 and MCNPX) and deterministic (ERANOS, VARIANT, and PARTISN) codes. When the assembly is driven by a pulsed neutron source generated by a particle accelerator and delayed neutrons are at equilibrium, the Sjöstrand method becomes extremely fast if the integral of the reaction rate frommore » a single pulse is split into two parts. These two integrals distinguish between the neutron counts during and after the pulse period. To conclude, when the facility is driven by a spontaneous fission neutron source, the timestamps of the detector neutron counts can be obtained up to the nanosecond precision using MCNP6, which allows obtaining the Rossi and Feynman distributions.« less
NASA Astrophysics Data System (ADS)
Trahan, Alexis Chanel
New nondestructive assay techniques are sought to better characterize spent nuclear fuel. One of the NDA instruments selected for possible deployment is differential die-away self-interrogation (DDSI). The proposed DDSI approach for spent fuel assembly assay utilizes primarily the spontaneous fission and (alpha, n) neutrons in the assemblies as an internal interrogating radiation source. The neutrons released in spontaneous fission or (alpha,n) reactions are thermalized in the surrounding water and induce fission in fissile isotopes, thereby creating a measurable signal from isotopes of interest that would be otherwise difficult to measure. The DDSI instrument employs neutron coincidence counting with 3He tubes and list-mode-based data acquisition to allow for production of Rossi-alpha distributions (RADs) in post-processing. The list-mode approach to data collection and subsequent construction of RADs has expanded the analytical possibilities, as will be demonstrated throughout this thesis. One of the primary advantages is that the measured signal in the form of a RAD can be analyzed in its entirety including determination of die-away times in different time domains. This capability led to the development of the early die-away method, a novel leakage multiplication determination method which is tested throughout the thesis on different sources in simulation space and fresh fuel experiments. The early die-away method is a robust, accurate, improved method of determining multiplication without the need for knowledge of the (alpha,n) source term. The DDSI technique and instrument are presented along with the many novel capabilities enabled by and discovered through RAD analysis. Among the new capabilities presented are the early die-away method, total plutonium content determination, and highly sensitive missing pin detection. Simulation of hundreds of different spent and fresh fuel assemblies were used to develop the analysis algorithms and the techniques were tested on a variety of spontaneous fission-driven fresh fuel assemblies at Los Alamos National Laboratory and the BeRP ball at the Nevada National Security Site. The development of the new, improved analysis and characterization methods with the DDSI instrument makes it a viable technique for implementation in a facility to meet material control and safeguards needs.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Geslot, Benoit; Pepino, Alexandra; Blaise, Patrick
A pile noise measurement campaign has been conducted by the CEA in the VENUS-F reactor (SCK-CEN, Mol Belgium) in April 2011 in the reference critical configuration of the GUINEVERE experimental program. The experimental setup made it possible to estimate the core kinetic parameters: the prompt neutron decay constant, the delayed neutron fraction and the generation time. A precise assessment of these constants is of prime importance. In particular, the effective delayed neutron fraction is used to normalize and compare calculated reactivities of different subcritical configurations, obtained by modifying either the core layout or the control rods position, with experimental onesmore » deduced from the analysis of measurements. This paper presents results obtained with a CEA-developed time stamping acquisition system. Data were analyzed using Rossi-α and Feynman-α methods. Results were normalized to reactor power using a calibrated fission chamber with a deposit of Np-237. Calculated factors were necessary to the analysis: the Diven factor was computed by the ENEA (Italy) and the power calibration factor by the CNRS/IN2P3/LPC Caen. Results deduced with both methods are consistent with respect to calculated quantities. Recommended values are given by the Rossi-α estimator, that was found to be the most robust. The neutron generation time was found equal to 0.438 ± 0.009 μs and the effective delayed neutron fraction is 765 ± 8 pcm. Discrepancies with the calculated value (722 pcm, calculation from ENEA) are satisfactory: -5.6% for the Rossi-α estimate and -2.7% for the Feynman-α estimate. (authors)« less
NASA Astrophysics Data System (ADS)
Kaplan, Alexis C.; Henzl, Vladimir; Menlove, Howard O.; Swinhoe, Martyn T.; Belian, Anthony P.; Flaska, Marek; Pozzi, Sara A.
2014-11-01
As a part of the Next Generation Safeguards Initiative Spent Fuel project, we simulate the response of the Differential Die-away Self-Interrogation (DDSI) instrument to determine total elemental plutonium content in an assayed spent nuclear fuel assembly (SFA). We apply recently developed concepts that relate total plutonium mass with SFA multiplication and passive neutron count rate. In this work, the multiplication of the SFA is determined from the die-away time in the early time domain of the Rossi-Alpha distributions measured directly by the DDSI instrument. We utilize MCNP to test the method against 44 pressurized water reactor SFAs from a simulated spent fuel library with a wide dynamic range of characteristic parameters such as initial enrichment, burnup, and cooling time. Under ideal conditions, discounting possible errors of a real world measurement, a root mean square agreement between true and determined total Pu mass of 2.1% is achieved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Klain, Kimberly L.
The behavior of symmetrical coupled-core systems has been extensively studied, yet there is a dearth of research on asymmetrical systems due to the increased complexity of the analysis of such systems. In this research, the multipoint kinetics method is applied to asymmetrical zeropower, subcritical, bare metal reactor systems. Existing research on asymmetrical reactor systems assumes symmetry in the neutronic coupling; however, it will be shown that this cannot always be assumed. Deep subcriticality adds another layer of complexity and requires modification of the multipoint kinetics equations to account for the effect of the external neutron source. A modified set ofmore » multipoint kinetics equations is derived with this in mind. Subsequently, the Rossi-alpha equations are derived for a two-region asymmetrical reactor system. The predictive capabilities of the radiation transport code MCNP6 for neutron noise experiments are shown in a comparison to the results of a series of Rossi-alpha measurements performed by J. Mihalczo utilizing a coupled set of symmetrical bare highly-enriched uranium (HEU) cylinders. The ptrac option within MCNP6 can generate time-tagged counts in a cell (list-mode data). The list-mode data can then be processed similarly to measured data to obtain values for system parameters such as the dual prompt neutron decay constants observable in a coupled system. The results from the ptrac simulations agree well with the historical measured values. A series of case studies are conducted to study the effects of geometrical asymmetry in the coupling between two bare metal HEU cylinders. While the coupling behavior of symmetrical systems has been reported on extensively, that of asymmetrical systems remains sparse. In particular, it appears that there has been no previous research in obtaining the coupling time constants for asymmetrically-coupled systems. The difficulty in observing such systems is due in part to the inability to determine the individual coupling coefficients from measurement: unlike the symmetrical cases, only the product of the values can be obtained. A method is proposed utilizing MCNP6 tally ratios to separate the coupling coefficients for such systems. This work provides insight into the behavior of asymmetrically-coupled systems as the separation distance between the two cores is changed and also as the asymmetry is increased. As the asymmetry increases, both the slower and the faster observable prompt neutron decay constants increase in magnitude. The coupling time constants are determined from the measured decay constants. As the separation distance increases, both coupling coefficients decrease as expected. Based on these findings, an effective computational method utilizing MCNP6 and the Rossialpha technique can be applied to the prediction of asymmetrical coupled system measurements.« less
Characterization of Ignition and Combustion Properties of Nanowire-based Energetics
2013-07-23
Sannia, A. Cincotti, G. Cao, Chem. Eng. Sci. 54 (15–16) (1999) 3053–3061. [4] C. Rossi, K. Zhang, D. Esteve, P. Alphonse , P. Tailhades, C. Vahlas, J...94 (5) (2003) 2923–2929. [30] K. Zhang, C. Rossi, G.A.A. Rodriguez, C. Tenail- leau, P. Alphonse , Appl. Phys. Lett. 91 (11) (2007) 113117/1–113117/3...Pister, Smart Mater. Struct. 10(6), 1145 (2001). 8C. Rossi, K. Zhang, D. Esteve, P. Alphonse , P. Tailhades, and C. Vahlas, J. Microelectromech. Syst. 16
Rossi and high-energy astronomy
NASA Astrophysics Data System (ADS)
Clark, George W.
2012-03-01
The contributions of Bruno Rossi to high-energy astronomy began in Italy in the 1930s with investigations concerning the nature of cosmic rays in theory and in hands-on experiments at the universities of Florence and Padua. Recent discoveries had cast doubt on Robert Millikan's idea that the primary cosmic rays are gamma rays created in the production of the elements by fusion of hydrogen atoms in interstellar space. Rossi entered the field with a prediction published in 1930 of a difference between the intensity of cosmic rays from the east and the west that would occur if the primary cosmic rays were charged particles of one sign. In the same year he invented the first practical electronic coincidence circuit, which he used in a series of fundamental particle experiments and in an unsuccessful attempt to detect an east-west effect at Florence. Expecting by theory that the effect would be greater at high altitude near the equator, he took his experiment to Eritrea in 1934 where his measurements demonstrated that the primary cosmic rays are predominantly positive particles. In the report of his expedition he also described his discovery of extensive cosmic-ray air showers. After WWII and his work at Los Alamos, Rossi resumed his cosmic-ray research, now at MIT, in a new style best described in his own words: ``Now I had the responsibility of an entire group, and what mattered was no longer my own work, but the work of the group.'' He suggested the new methods of ``density sampling'' and ``fast timing'' for air shower studies, and promoted their application in numerous experiments on the nature and origins of the highest energy cosmic rays. In 1959 he initiated and participated as a consultant in the work of Riccardo Giacconi that led to the discovery of the first x-ray star, Sco X-1, and the development of the first imaging x-ray telescopes. At MIT, members of the Rossi Cosmic Ray Group took the early steps in gamma-ray astronomy, first with balloon experiments that set lower and lower limits on the intensity of primary gamma rays, and then with the satellite experiments led by William Kraushaar that discovered the galactic and extra-galactic components of cosmic gamma rays. After Sco X-1, Rossi focused his efforts on exploring the solar wind and the interplanetary plasma while leaving his younger colleagues to pursue the new field of extra-solar x-ray astronomy with balloon, rocket, and satellite experiments.
Interview of Professor Lucio Rossi about the First Beam
None
2017-12-09
Lucio Rossi: Head of the Magnets, Cryostats and Superconductors Group, CERN Questions asked : 1. What does it take to start up the LHC machine? 2. What's the plan for 1st injection day? 3. How do you feel about this?
Takeet, Michael I; Oyewusi, Adeoye J; Abakpa, Simon A V; Daramola, Olukayode O; Peters, Sunday O
2017-03-01
Adequate knowledge of the genetic diversity among Babesia species infecting dogs is necessary for a better understanding of the epidemiology and control of canine babesiosis. Hence, this study determined the genetic diversity among the Babesia rossi detected in dogs presented for routine examination in Veterinary Hospitals in Abeokuta, Nigeria. Blood were randomly collected from 209 dogs. Field-stained thin smears were made and DNA extracted from the blood. Partial region of the 18S small subunit ribosomal RNA (rRNA) gene was amplified, sequenced and analysed. Babesia species was detected in 16 (7.7%) of the dogs by microscopy. Electrophoresed PCR products from 39 (18.66%) dogs revealed band size of 450 bp and 2 (0.95%) dogs had band size of 430 bp. The sequences obtained from 450 bp amplicon displayed homology of 99.74% (387/388) with partial sequences of 18S rRNA gene of Babesia rossi in the GeneBank. Of the two sequences that had 430 bp amplicon, one was identified as T. annulata and second as T. ovis. A significantly (p<0.05) higher prevalence of B. rossi was detected by PCR compared to microscopy. The mean PCV of Babesia infected dogs was significantly (p<0.05) lower than non-infected dogs. Phylogenetic analysis revealed minimal diversity among B. rossi with the exception of one sequence that was greatly divergent from the others. This study suggests that more than one genotype of B. rossi may be in circulation among the dog population in the study area and this may have potential implication on clinical outcome of canine babesiosis.
Leon Van Speybroeck Wins Astrophysics Bruno Rossi Prize
NASA Technical Reports Server (NTRS)
2002-01-01
Leon Van Speybroeck of the Harvard-Smithsonian Center for Astrophysics in Cambridge Massachusetts was awarded the 2002 Bruno Rossi Prize of the High-Energy Astrophysics Division of the American Astronomy Society. The Rossi Prize is an arnual recognition of significant contributions in high-energy astrophysics in honor of the Massachusetts Institute of Technology's late Professor Bruno Rossi, an authority on cosmic ray physics and a pioneer in the field of x-ray astronomy. Van Speybroeck, who led the effort to design and make the x-ray mirrors for NASA's premier Chandra X-Ray Observatory, was recognized for a career of stellar achievements in designing precision x-ray optics. As Telescope Scientist for Chandra, he has worked for more than 20 years with a team that includes scientists and engineers from the Harvard-Smithsonian, NASA's Marshall Space Flight Center, TRW, Inc., Huhes-Danbury (now B.F. Goodrich Aerospace), Optical Coating Laboratories, Inc., and Eastman-Kodak on all aspects of the x-ray mirror assembly that is the heart of the observatory.
Molecular characterization of Babesia species in wild animals and their ticks in Turkey.
Orkun, Ömer; Karaer, Zafer
2017-11-01
To date, no study has investigated Babesia ecology in wild boars, hares or foxes in Turkey. This study aimed to determine and characterize Babesia spp. in wild animals and their ticks. We identified a novel Babesia genotype and four known Babesia species in wild animals and their ticks. We detected Babesia spp. molecularly in hares for the first time. In addition, we identified B. vulpes in foxes for the first time in Turkey. The presence of B. rossi, B. crassa and B. occultans was also revealed in ticks collected from wild boars and hares. This is only the second report of B. rossi in ticks outside of Africa and suggests that B. rossi is circulating in ticks in Turkey. Therefore B. rossi poses a significant threat to domestic dogs. Here we demonstrate the role of wild animals in the life cycle of Babesia species in Turkey and contribute to Babesia ecological and taxonomic information. Copyright © 2017 Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Krieger, G L
1976-06-01
W (the average energy to form an ion pair) for 5.4 MeV /sup 241/Am alpha particles in a Rossi-type tissue equivalent (T.E.) gas, argon and methane was determined to an accuracy better than 0.2% using a new automated data handling system. A vibrating reed electrometer and current digitizer were used to measure the current produced by completely stopping the alpha particles in a large cylindrical ionization chamber. A multichannel analyzer, operating in a slow multiscalar mode, was used to store pulses from the current digitizer. The dwell time, on the order of 60 minutes per channel, was selected with anmore » external timer gate. Current measurements were made at reduced pressures (approximately 200 torr) to reduce ion-recombination. The average current, over many repeated measurements, was compared to the current produced in nitrogen and its previously published W-value of 36.39 +- 0.04 eV/ion pair. The resulting W-values were (in eV/ion pair): 26.29 +- 0.05 for argon, 29.08 +- 0.03 for methane and 30.72 +- 0.04 for T.E. gas, which had an analyzed composition of 64.6% methane, 32.4% CO/sub 2/, and 2.7% nitrogen. Although the methane and argon values agree within 0.1% with previously published values, the value for T.E. is 1.2% lower than the single previously reported value.« less
Measuring and Modeling Cosmic Ray Showers with an MBL System: An Undergraduate Project.
ERIC Educational Resources Information Center
Jackson, David P.; Welker, Matthew T.
2001-01-01
Describes a novel method for inducing and measuring cosmic ray showers using a low-cost, microcomputer-based laboratory system. Uses low counting-rate radiation monitors in the reproduction of Bruno Rossi's classic experiment. (Contains 16 references.) (Author/YDS)
Ayuso, Robert; Foley, Nora K.; Brown, C. Erwin
1987-01-01
The present study of fluid inclusions and lead isotopes was done to understand better the nature and possible source of the mineralizing solutions for both vertical and gash veins and the possible origin of the lead and zinc mineralization. Large deposits of essentially syngenetic sphalerite with minor to trace galena occur in the Proterozoic rocks of this region (e.g., Balmat-Edwards, New York). Although none of these deposits are known in the immediate vicinity of Rossie veins, the possibility that Rossie veins contain remobilized metals from these older deposits was considered.
Egg parasitoid of Saccharosydne subandina (Hemiptera: Delphacidae) in Neuquen, Argentina
USDA-ARS?s Scientific Manuscript database
Saccharosydne subandina Remes Lenicov & Rossi Batiz is a recently described planthopper from Argentina which is known to feed on garlic, rye, and pampas grass (de Remes-Lenicov & Rossi-Batiz 2010). During a trip to Neuquén Province in February 2007, we noticed a heavy infestation of pampas grass, Co...
An Intimate Portrait of Evaluation Mentorship under Peter H. Rossi
ERIC Educational Resources Information Center
Chen, Huey T.
2007-01-01
The author grew up in Taiwan and in 1995 enrolled in Kent State University's PhD program in sociology. Early in his doctoral career at Kent State, he took a program evaluation course offered by Irwin Deutscher. The textbook he used in the class was Peter Rossi and Walter Williams's 1972 book, "Evaluating Social Programs: Theory, Practice, and…
The Impact of Nanotechnology Energetics on the Department of Defense by 2035
2010-02-17
Kaili Zhang, Daniel Esteve, Pierre Alphonse , Philippe Tailhades and Constantin Vahlas. “Nano-Energetic Materials for MEMS: A Review.” Journal of...on impact and the energetic compounds react. 16 Rossi, Carole, Kaili Zhang, Daniel Esteve, Pierre Alphonse , Philippe Tailhades and Constantin Vahlas...Rossi, Carole, Kaili Zhang, Daniel Esteve, Pierre Alphonse , Philippe Tailhades and Constantin Vahlas. “Nano-Energetic Materials for
Oyamada, Maremichi; Davoust, Bernard; Boni, Mickaël; Dereure, Jacques; Bucheton, Bruno; Hammad, Awad; Itamoto, Kazuhito; Okuda, Masaru; Inokuma, Hisashi
2005-01-01
Babesia and Hepatozoon infections of dogs in a village of eastern Sudan were analyzed by using a single PCR and sequencing. Among 78 dogs, 5 were infected with Babesia canis rossi and 2 others were infected with B. canis vogeli. Thirty-three dogs were positive for Hepatozoon. Hepatozoon canis was detected by sequence analysis. PMID:16275954
Oyamada, Maremichi; Davoust, Bernard; Boni, Mickaël; Dereure, Jacques; Bucheton, Bruno; Hammad, Awad; Itamoto, Kazuhito; Okuda, Masaru; Inokuma, Hisashi
2005-11-01
Babesia and Hepatozoon infections of dogs in a village of eastern Sudan were analyzed by using a single PCR and sequencing. Among 78 dogs, 5 were infected with Babesia canis rossi and 2 others were infected with B. canis vogeli. Thirty-three dogs were positive for Hepatozoon. Hepatozoon canis was detected by sequence analysis.
Normal and Differential SAR Interferometry
2007-02-01
incorporating the use of a rough DEM. [ Adragna 1995]. The same technique is also used for flat Earth removal, and for differential Interferometry (Chap..5...available at http://www.estec.esa.nl/confannoun/99b02/index.html Massonnet, D., K. Feigi, M. Rossi, and F. Adragna , 1994. Radar Interferometric Mapping...of Deformation in the Year After the Landers Earthquake, Nature, Vol. 369, pp. 227-230 Massonnet, D., M. Rossi, C. Carmona, F. Adragna , G. Peltzer
Moments in the Life of a Scientist
NASA Astrophysics Data System (ADS)
Rossi, Bruno
1990-08-01
Bruno Rossi has long been an influential figure in diverse areas of physics and in this volume he presents a fascinating account of his life and work as an experimental physicist. He discusses his scientific contributions, from experiments that played a major role in establishing the nature and properties of cosmic rays to those establishing the existence of a solar wind and others that laid the foundations of X-ray astronomy. Rossi provides close insight into his actual experiences as a scientist and the motivations that gave direction to his research, and he recounts the beginning of very significant stages in high energy physics and space research. He writes evocatively of the many places where he worked--of Florence, Arcetri, Padua, and Venice, of the mountains of Colorado and the deserts of New Mexico. His narrative also provides insight into the life of a Jewish family in fascist Italy. The text is accompanied by photographs taken throughout Rossi's career.
NASA Astrophysics Data System (ADS)
Bonolis, Luisa
2014-01-01
Bruno Rossi is considered one of the fathers of modern physics, being also a pioneer in virtually every aspect of what is today called high-energy astrophysics. At the beginning of 1930s he was the pioneer of cosmic ray research in Italy, and, as one of the leading actors in the study of the nature and behavior of the cosmic radiation, he witnessed the birth of particle physics and was one of the main investigators in this fields for many years. While cosmic ray physics moved more and more towards astrophysics, Rossi continued to be one of the inspirers of this line of research. When outer space became a reality, he did not hesitate to leap into this new scientific dimension. Rossi's intuition on the importance of exploiting new technological windows to look at the universe with new eyes, is a fundamental key to understand the profound unity which guided his scientific research path up to its culminating moments at the beginning of 1960s, when his group at MIT performed the first in situ measurements of the density, speed and direction of the solar wind at the boundary of Earth's magnetosphere, and when he promoted the search for extra-solar sources of X rays. A visionary idea which eventually led to the breakthrough experiment which discovered Scorpius X-1 in 1962, and inaugurated X-ray astronomy.
Reymond, Claire E; Lloyd, Alicia; Kline, David I; Dove, Sophie G; Pandolfi, John M
2013-01-01
The combination of global and local stressors is leading to a decline in coral reef health globally. In the case of eutrophication, increased concentrations of dissolved inorganic nitrogen (DIN) and phosphorus (DIP) are largely attributed to local land use changes. From the global perspective, increased atmospheric CO2 levels are not only contributing to global warming but also ocean acidification (OA). Both eutrophication and OA have serious implications for calcium carbonate production and dissolution among calcifying organisms. In particular, benthic foraminifera precipitate the most soluble form of mineral calcium carbonate (high-Mg calcite), potentially making them more sensitive to dissolution. In this study, a manipulative orthogonal two-factor experiment was conducted to test the effects of dissolved inorganic nutrients and OA on the growth, respiration and photophysiology of the large photosymbiont-bearing benthic foraminifer, Marginopora rossi. This study found the growth rate of M. rossi was inhibited by the interaction of eutrophication and acidification. The relationship between M. rossi and its photosymbionts became destabilized due to the photosymbiont's release from nutrient limitation in the nitrate-enriched treatment, as shown by an increase in zooxanthellae cells per host surface area. Foraminifers from the OA treatments had an increased amount of Chl a per cell, suggesting a greater potential to harvest light energy, however, there was no net benefit to the foraminifer growth. Overall, this study demonstrates that the impacts of OA and eutrophication are dose dependent and interactive. This research indicates an OA threshold at pH 7.6, alone or in combination with eutrophication, will lead to a decline in M. rossi calcification. The decline in foraminifera calcification associated with pollution and OA will have broad ecological implications across their ubiquitous range and suggests that without mitigation it could have serious implications for the future of coral reefs. © 2012 Blackwell Publishing Ltd.
Human Immunodeficiency Virus (HIV) Infections; Strain and Type Variations; Diagnosis and Prevention.
1992-10-26
Scarlatti et al. 1992 (41) 1 1 Arendrup et al. 1992 (42) SIVsm/monkey 7 0 Zhang et al. manuscript (43) B) Sequential samples: serum collected >6 months...983-990. 1991. 12. Scarlatti , G, Lombardi, V, Plebani, A, Principi, N, Chiara, V, Ferraris, G, Bucceri, A, Feny6, E M, Wigzell, H, Rossi, P, and...envelope glycoprotein gp125 of human immunodeficiency virus type2. Manuscript. M2. Scarlatti , G, Albert, J, Rossi, P, Hodara, V, Biraghi, P, Muggiasca
Transforming Graph Data for Statistical Relational Learning
2012-10-01
Jordan, 2003), PLSA (Hofmann, 1999), ? Classification via RMN (Taskar et al., 2003) or SVM (Hasan, Chaoji, Salem , & Zaki, 2006) ? Hierarchical...dimensionality reduction methods such as Principal 407 Rossi, McDowell, Aha, & Neville Component Analysis (PCA), Principal Factor Analysis ( PFA ), and...clustering algorithm. Journal of the Royal Statistical Society. Series C, Applied statistics, 28, 100–108. Hasan, M. A., Chaoji, V., Salem , S., & Zaki, M
History of Chandra X-Ray Observatory
2002-01-23
Leon Van Speybroeck of the Harvard-Smithsonian Center for Astrophysics in Cambridge Massachusetts was awarded the 2002 Bruno Rossi Prize of the High-Energy Astrophysics Division of the American Astronomy Society. The Rossi Prize is an arnual recognition of significant contributions in high-energy astrophysics in honor of the Massachusetts Institute of Technology's late Professor Bruno Rossi, an authority on cosmic ray physics and a pioneer in the field of x-ray astronomy. Van Speybroeck, who led the effort to design and make the x-ray mirrors for NASA's premier Chandra X-Ray Observatory, was recognized for a career of stellar achievements in designing precision x-ray optics. As Telescope Scientist for Chandra, he has worked for more than 20 years with a team that includes scientists and engineers from the Harvard-Smithsonian, NASA's Marshall Space Flight Center, TRW, Inc., Huhes-Danbury (now B.F. Goodrich Aerospace), Optical Coating Laboratories, Inc., and Eastman-Kodak on all aspects of the x-ray mirror assembly that is the heart of the observatory.
2005-01-01
in Brazil. J Med Virol 59: 527–535. 7. Lopez N, Padula P, Rossi C, Lazaro ME, Franze-Fernandez MT, 1996. Genetic identification of a new hantavirus...177: 529–538. 10. Toro J, Vega JD, Khan AS, Mills JN, Padula P, Terry W, Yadon Z, Valderrama R, Ellis BA, Pavletic C, Cerda R, Zaki S, Wun- Ju S, Meyer...Chile, 1997. Emerg Infect Dis 4: 687–694. 11. Padula PJ, Rossi CM, Della Valle MO, Martinez PV, Colavecchia SB, Edelstein A, Miguel SD, Rabinovich RD
Matjila, Paul Tshepo; Leisewitz, Andrew L; Jongejan, Frans; Bertschinger, Henk J; Penzhorn, Barend L
2008-10-20
Blood specimens from wild dogs (n=301) were obtained from De Wildt Cheetah and Wildlife Centre (Pretoria) and five game reserves (4 in the North-West Province and 1 in Limpopo Province), South Africa. Specimens were screened for Babesia, Theileria, Hepatozoon and Ehrlichia/Anaplasma species using PCR and Reverse Line Blot (RLB) assays. Positive results were obtained in 18 (6%) wild dogs. Sixteen specimens were found positive for Babesia rossi and two dogs were Hepatozoon sp. positive. It appears that these tick-borne pathogens are not widely distributed in wild dog populations.
DOE Office of Scientific and Technical Information (OSTI.GOV)
McKenzie, IV, George Espy; Goda, Joetta Marie; Grove, Travis Justin
This paper examines the comparison of MCNP® code’s capability to calculate kinetics parameters effectively for a thermal system containing highly enriched uranium (HEU). The Rossi-α parameter was chosen for this examination because it is relatively easy to measure as well as easy to calculate using MCNP®’s kopts card. The Rossi-α also incorporates many other parameters of interest in nuclear kinetics most of which are more difficult to precisely measure. The comparison looks at two different nuclear data libraries for comparison to the experimental data. These libraries are ENDF/BVI (.66c) and ENDF/BVII (.80c).
Comparison of the X-Ray and Radio Light Curves of Quasar PKS 1510--089
NASA Technical Reports Server (NTRS)
Aller, M. F.; Marscher, A. P.; Marchenko-Jorstad, S. G.; McHardy, I. M.; Aller, H. D.
1998-01-01
We present results for the X-ray-bright superluminal AGN PKS 1510-089 (z=0.36) monitored weekly with the Rossi X-Ray Timing Explorer for the past four years in order to study the origin of X-ray emission from this extremely variable blazer. These RXTE data are compared with weekly cm-band flux and polarization observations from the Michigan Diameter telescope, to identify correlated activity and associated frequency-dependent time delays for constraining X-ray emission models; and bimonthly 7mm VLBA total and linearly polarized intensity imaging to identify temporal associations between X-ray events and the ejection of superluminal components and disturbances in the magnetic field, to test if the X-ray energy release is related to changes in the inner jet flow. Both the X-ray (2-20 keV) and radio flux are highly variable on timescales of weeks. The VLBA mas structure is dominated by a bright core with a weak jet; both the ejection of very fast superluminal knots and changes in the fractional polarization and EVPA of the core on timescales of one to four months are identified. Two outbursts in 1997 are well-resolved in both the centimeter and X-ray bands. Both the strong temporal association and the similar outburst shape support a causal relation, and a discrete cross-correlation analysis identifies that the X-ray lags the radio by 16 days during the bursts. Starting in 1998 the behavior changes: the correlation is weaker with the X-ray possibly leading the radio by six days. During the full time window there is a correlation between bands as expected if the radio photons are upscattered to X-ray energies. The time correlations and difference between the flat X-ray spectral index (0.0 <= alpha <= 0.5 where F(sub v) is proportional to v(exp -alpha)), and the mm-wave synchrotron spectrum (alpha = 0.8) are discussed within the framework of viable SSC models.
Prefazione al secondo volume di GERBERTVS
NASA Astrophysics Data System (ADS)
Sigismondi, Costantino
The act of the symposium Gerbertus Magister et Pastor held in Rome on May 2, 2011 and dedicated to the studies and to the activities of Gerbert of Aurillac, scientist, astronomer and pope. Here are presented the papers of Flavio G. Nuvolone, Paolo Rossi on historical subjects: Gerbert and king Lotarius, and the relationships between Gerbert and the Empire, with the choice of the name Sylvester. Finally Maurizio Chirri presents a study on the sources of the Geometry written by Gerbert, which contains also some astronomical methods as usual in the treatises of that epoch.
Schoeman, J P; Herrtage, M E
2007-12-01
This prospective, cross-sectional, interventional study was designed to determine the association between the hormones of the pituitary-adrenal and pituitary-thyroid axes and other clinical parameters with the blood glucose perturbations in dogs with naturally occurring Babesia canis rossi babesiosis. Thirty-six dogs with canine babesiosis were studied. Blood samples were obtained from the jugular vein in each dog prior to treatment at admission to hospital and serum endogenous adrenocorticotrophic hormone (ACTH), pre-ACTH cortisol, thyroxine, free thyroxine and TSH concentrations were measured. Immediately thereafter each dog was injected intravenously with 5 microg/kg of ACTH (tetracosactrin). A 2nd blood sample was taken 1 hour later for serum post-ACTH cortisol measurement. Three patient groups were recruited: hypoglycaemic dogs (glucose < 3.3 mmol/l, n = 12); normoglycaemic dogs (glucose 3.3-5.5 mmol/l, n = 12); hyperglycaemic dogs (glucose > 5.5 mmol/l, n = 12). Basal and post-ACTH serum cortisol concentrations were significantly higher in hypoglycaemic dogs, whereas body temperature, serum thyroxine and free thyroxine were significantly lower in hypoglycaemic dogs. Haematocrit was significantly lower in both hypo-and hyperglycaemic dogs compared with normoglycaemic dogs. Low blood glucose concentrations were significantly associated with high basal and post-ACTH cortisol concentrations and with low serum thyroxine and free thyroxine concentrations in dogs suffering from B. canis rossi babesiosis.
Rossi X-Ray Timing Explorer All-Sky Monitor Localization of SGR 1627-41
NASA Astrophysics Data System (ADS)
Smith, Donald A.; Bradt, Hale V.; Levine, Alan M.
1999-07-01
The fourth unambiguously identified soft gamma repeater (SGR), SGR 1627-41, was discovered with the BATSE instrument on 1998 June 15. Interplanetary Network (IPN) measurements and BATSE data constrained the location of this new SGR to a 6° segment of a narrow (19") annulus. We present two bursts from this source observed by the All-Sky Monitor (ASM) on the Rossi X-Ray Timing Explorer. We use the ASM data to further constrain the source location to a 5' long segment of the BATSE/IPN error box. The ASM/IPN error box lies within 0.3 arcmin of the supernova remnant G337.0-0.1. The probability that a supernova remnant would fall so close to the error box purely by chance is ~5%.
Energy Spectra and High Frequency Oscillations in 4U 0614+091
NASA Technical Reports Server (NTRS)
Ford, E. C.; Kaaret, P.; Chen, K.; Tavani, M.; Barret, D.; Bloser, P.; Grindlay, J.; Harmon, B. A.; Paciesas, W. S.; Zhang, S. N.
1997-01-01
We investigate the behavior of the high frequency quasi-periodic oscillations (QPOs) in 4U 0614+091, combining timing and spectral analysis of RXTE (Rossi X-ray Timing Explorer) observations. The energy spectrum of the source can be described by a power law plus a blackbody component. The blackbody has a variable temperature (kT approximately 0.8 to 1.4 keV) and accounts for 10 to 25% of the total energy flux. The power law flux and photon index also vary (F approximately 0.8 to 1.6 x 10(exp -9) erg/sq cm.s and alpha approximately 2.0 to 2.8 respectively). We find a robust correlation of the frequency of the higher frequency QPO with the flux of the blackbody. The source follows the same relation even in observations separated by several months. The QPO frequency does not have a similarly unique correlation with the total flux or the flux of the power law component. The RMS amplitudes of the higher frequency QPO rise with energy but are consistent with a constant for the lower frequency QPO. These results may be interpreted in terms of a beat frequency model for the production of the high frequency QPOs.
XTE J1946+274: An Enigmatic X-Ray Pulsar
NASA Technical Reports Server (NTRS)
Wilson, Colleen A.; Finger, Mark H.; Coe, M. J.; Negueruela, Ignacio; Six, N. Frank (Technical Monitor)
2002-01-01
XTE J1946+274 = GRO J1944+26 is a 15.8-s X-ray pulsar discovered simultaneously by the Rossi X-ray Timing Explorer (RXTE) and the Burst and Transient Source Experiment (BATSE) in September 1998. Follow-up optical/IR observations resulted in the discovery of a Be star companion. Our pulse timing analysis of BATSE and RXTE data indicates that the orbital period is approximately 169 days. Since its discovery in 1998, XTE J1946+274 has undergone 13 outbursts. These outbursts axe not regularly spaced. They occur approximately twice per orbit and are not locked in orbital phase, unlike most Be/X-ray transient systems. A possible explanation for this is a global-one armed oscillation or density perturbation propagating rapidly in the Be star's disk. We will investigate radial velocity variations in the central peak of the H-alpha line to look for evidence of such a perturbation. From 2001 March-September, we regularly monitored XTE J1946+274 with the RXTE PCA. We will demonstrate that the spectrum appears to be varying with orbital phase, based on the 2001 and 1998 RXTE PCA observations. We will also present histories of pulsed frequency and flux.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Levine, Alan M.; Bradt, Hale V.; Chakrabarty, Deepto
2011-09-01
We present the results of a systematic search in {approx}14 years of Rossi X-ray Timing Explorer All-Sky Monitor (ASM) data for evidence of periodicities. Two variations of the commonly used Fourier analysis search method have been employed to significantly improve upon the sensitivity achieved by Wen et al. in 2006, who also searched for periodicities in ASM data. In addition, the present search is comprehensive in terms of sources studied and frequency range covered, and has yielded the detection of the signatures of the orbital periods of eight low-mass X-ray binary systems and of ten high-mass X-ray binaries not listedmore » in the tables of Wen et al. Orbital periods, epochs, signal amplitudes, modulation fractions, and folded light curves are given for each of these systems. Seven of the orbital periods are the most precise reported to date. In the course of this work, the 18.545 day orbital period of IGR J18483-0311 was co-discovered, and the first detections in X-rays were made of the {approx}3.9 day orbital period of LMC X-1 and the {approx}3.79 hr orbital period of 4U 1636-536. The results inform future searches for orbital and other periodicities in X-ray binaries.« less
Genetics Home Reference: multiple myeloma
... percent of cancers of the blood and blood-forming tissues, and between one and two percent of ... Jurado M, Landi S, Rossi AM, Lesueur F, Marques H, Dudziński M, Wątek M, Moreno V, Orciuolo E, ...
Genetics Home Reference: atelosteogenesis type 2
... 49-53. Review. Citation on PubMed or Free article on PubMed Central Rossi A, Superti-Furga A. Mutations in the diastrophic dysplasia sulfate transporter (DTDST) gene (SLC26A2): 22 novel mutations, mutation review, associated skeletal ...
Bruno Rossi and the Racial Laws of Fascist Italy
NASA Astrophysics Data System (ADS)
Bonolis, Luisa
2011-03-01
Bruno Rossi (1905-1993), one of the giants of 20th-century physics, was a pioneer in cosmic-ray physics and virtually every other aspect of high-energy astrophysics. His scientific career began at the University of Florence in 1928 and continued at the University of Padua until 1938, when the Fascist anti-Semitic racial laws were passed in Italy. He was dismissed from his professorship and was forced to emigrate, as described in unpublished letters and documents that display the international character of physics and physicists. His young bride Nora Lombroso, his love of physics, and the solidarity of the physics community gave him the courage to begin a new life in Copenhagen, Manchester, and in the New World at the University of Chicago, Cornell University, Los Alamos, and after the Second World War at the Massachusetts Institute of Technology where he became the center of a worldwide research network.
Bonolis, Luisa
2014-07-01
During the 1920s and 1930s, Italian physicists established strong relationships with scientists from other European countries and the United States. The career of Bruno Rossi, a leading personality in the study of cosmic rays and an Italian pioneer of this field of research, provides a prominent example of this kind of international cooperation. Physics underwent major changes during these turbulent years, and the traditional internationalism of physics assumed a more institutionalized character. Against this backdrop, Rossi's early work was crucial in transforming the study of cosmic rays into a branch of modern physics. His friendly relationships with eminent scientists--notably Enrico Fermi, Walther Bothe, Werner Heisenberg, Hans Bethe, and Homi Bhabha--were instrumental both for the exchange of knowledge about experimental practices and theoretical discussions, and for attracting the attention of physicists such as Arthur Compton, Louis Leprince-Ringuet, Pierre Auger and Patrick Blackett to the problem of cosmic rays. Relying on material from different archives in Europe and the United States, this case study aims to provide a glimpse of the intersection between national and international dimensions during the 1930s, at a time when the study of cosmic rays was still very much in its infancy, strongly interlaced with nuclear physics, and full of uncertain, contradictory, and puzzling results. Nevertheless, as a source of high-energy particles it became a proving ground for testing the validity of the laws of quantum electrodynamics, and made a fundamental contribution to the origins of particle physics.
Identification of Tick-Borne Pathogens in Ticks Feeding on Humans in Turkey
Orkun, Ömer; Karaer, Zafer; Çakmak, Ayşe; Nalbantoğlu, Serpil
2014-01-01
Background The importance of tick-borne diseases is increasing all over the world, including Turkey. The tick-borne disease outbreaks reported in recent years and the abundance of tick species and the existence of suitable habitats increase the importance of studies related to the epidemiology of ticks and tick-borne pathogens in Turkey. The aim of this study was to investigate the presence of and to determine the infection rates of some tick-borne pathogens, including Babesia spp., Borrelia burgdorferi sensu lato and spotted fever group rickettsiae in the ticks removed from humans in different parts of Ankara. Methodology/Principal Findings A total of 169 ticks belonging to the genus Haemaphysalis, Hyalomma, Ixodes and Rhipicephalus were collected by removing from humans in different parts of Ankara. Ticks were molecularly screened for Babesia spp., Borrelia burgdorferi sensu lato and spotted fever group rickettsiae by PCR and sequencing analysis. We detected 4 Babesia spp.; B. crassa, B. major, B. occultans and B. rossi, one Borrelia spp.; B. burgdorferi sensu stricto and 3 spotted fever group rickettsiae; R. aeschlimannii, R. slovaca and R. hoogstraalii in the tick specimens analyzed. This is the report showing the presence of B. rossi in a region that is out of Africa and in the host species Ha. parva. In addition, B. crassa, for which limited information is available on its distribution and vector species, and B. occultans, for which no conclusive information is available on its presence in Turkey, were identified in Ha. parva and H. marginatum, respectively. Two human pathogenic rickettsia species (R. aeschlimannii and R. slovaca) were detected with a high prevalence in ticks. Additionally, B. burgdorferi sensu stricto was detected in unusual tick species (H. marginatum, H. excavatum, Hyalomma spp. (nymph) and Ha. parva). Conclusions/Significance This study investigates both the distribution of several tick-borne pathogens affecting humans and animals, and the presence of new tick-borne pathogens in Turkey. More epidemiological studies are warranted for B. rossi, which is very pathogenic for dogs, because the presented results suggest that B. rossi might have a wide distribution in Turkey. Furthermore, we recommend that tick-borne pathogens, especially R. aeschlimannii, R. slovaca, and B. burgdorferi sensu stricto, should be taken into consideration in patients who had a tick bite in Turkey. PMID:25101999
Identification of tick-borne pathogens in ticks feeding on humans in Turkey.
Orkun, Ömer; Karaer, Zafer; Çakmak, Ayşe; Nalbantoğlu, Serpil
2014-08-01
The importance of tick-borne diseases is increasing all over the world, including Turkey. The tick-borne disease outbreaks reported in recent years and the abundance of tick species and the existence of suitable habitats increase the importance of studies related to the epidemiology of ticks and tick-borne pathogens in Turkey. The aim of this study was to investigate the presence of and to determine the infection rates of some tick-borne pathogens, including Babesia spp., Borrelia burgdorferi sensu lato and spotted fever group rickettsiae in the ticks removed from humans in different parts of Ankara. A total of 169 ticks belonging to the genus Haemaphysalis, Hyalomma, Ixodes and Rhipicephalus were collected by removing from humans in different parts of Ankara. Ticks were molecularly screened for Babesia spp., Borrelia burgdorferi sensu lato and spotted fever group rickettsiae by PCR and sequencing analysis. We detected 4 Babesia spp.; B. crassa, B. major, B. occultans and B. rossi, one Borrelia spp.; B. burgdorferi sensu stricto and 3 spotted fever group rickettsiae; R. aeschlimannii, R. slovaca and R. hoogstraalii in the tick specimens analyzed. This is the report showing the presence of B. rossi in a region that is out of Africa and in the host species Ha. parva. In addition, B. crassa, for which limited information is available on its distribution and vector species, and B. occultans, for which no conclusive information is available on its presence in Turkey, were identified in Ha. parva and H. marginatum, respectively. Two human pathogenic rickettsia species (R. aeschlimannii and R. slovaca) were detected with a high prevalence in ticks. Additionally, B. burgdorferi sensu stricto was detected in unusual tick species (H. marginatum, H. excavatum, Hyalomma spp. (nymph) and Ha. parva). This study investigates both the distribution of several tick-borne pathogens affecting humans and animals, and the presence of new tick-borne pathogens in Turkey. More epidemiological studies are warranted for B. rossi, which is very pathogenic for dogs, because the presented results suggest that B. rossi might have a wide distribution in Turkey. Furthermore, we recommend that tick-borne pathogens, especially R. aeschlimannii, R. slovaca, and B. burgdorferi sensu stricto, should be taken into consideration in patients who had a tick bite in Turkey.
Relativistically Skewed Iron Emission and Disk Reflection in Galactic Microquasar XTE J1748-288
NASA Technical Reports Server (NTRS)
Miller, J. M.; Fox, D. W.; DiMatteo, T.; Wijnands, R.; Belloni, T.; Kouveliotou, C.; Lewin, W. H. G.
2000-01-01
We report evidence for an Fe K-alpha fluorescence line feature in the Very High, High, and Low state X-ray spectra of the galactic microquasar XTE JI748-288 during its June 1998 outburst. Spectral analyses were made on observations spread across the outburst, gathered with the Rossi X-ray Timing Explorer. Gaussian line. disk emission line, relativistic disk emission line, and disk reflection models are fit to the data. In the Very High State, the line profile is strongly redshifted and consistent with emission from the innermost radius of a maximally rotating Kerr black hole, 1.235 R(sub g). The line profile is less redshifted in the High State, but increasingly prominent. In the Low State, the line profile is very strong and centered af approx. 6.7 keV; disk line emission models constrain the inner edge of the disk to fluctuate between approx.20 and approx.59 R(sub g). We trace the disk reflection fraction across the full outburst of this source, and find well-constrained fractions below those observed in AGN in the Very High and High States, but consistent with other galactic sources in the Low State. We discuss the possible implications for black hole X-ray binary system dynamics and accretion flow geometry.
Improved synthesis of 3 alpha, 7 alpha, 12 alpha, 24 = xi-tetrahydroxy-5 beta-cholestan-26-oic acid.
Batta, A K; Tint, G S; Dayal, B; Shefer, S; Salen, G
1982-06-01
This paper describes three simple and short methods for the conversion of cholic acid into cholylaldehyde with protected hydroxyl groups. The first method involves lithium aluminum hydride reduction of the tetrahydropyranyl ether of methyl cholate and oxidation of the resulting primary alcohol with pyridinium chlorochromate. The second method employs diborane for the reduction of the -COOH group to the -CH2OH group, while the third method involves the reduction of 3 alpha, 7 alpha, 12 alpha-triformyloxy-5 beta-cholan-24-oic acid (as the acid chloride) directly into 3 alpha, 7 alpha, 12 alpha-triformyloxy-5 beta-cholan-24-al with TMA-ferride (tetramethylammonium hydridoirontetracarbonyl). The aldehyde obtained by any of the above methods underwent smooth Reformatsky reaction with ethyl alpha-bromopropionate to yield 3 alpha, 7 alpha, 12 alpha, 24 xi-tetrahydroxy-5 beta-cholestan-26-oic acid.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Trahan, Alexis Chanel
New nondestructive assay techniques are sought to better characterize spent nuclear fuel. One of the NDA instruments selected for possible deployment is differential die-away self-interrogation (DDSI). The proposed DDSI approach for spent fuel assembly assay utilizes primarily the spontaneous fission and (α, n) neutrons in the assemblies as an internal interrogating radiation source. The neutrons released in spontaneous fission or (α,n) reactions are thermalized in the surrounding water and induce fission in fissile isotopes, thereby creating a measurable signal from isotopes of interest that would be otherwise difficult to measure. The DDSI instrument employs neutron coincidence counting with 3He tubesmore » and list-mode-based data acquisition to allow for production of Rossi-alpha distributions (RADs) in post-processing. The list-mode approach to data collection and subsequent construction of RADs has expanded the analytical possibilities, as will be demonstrated throughout this thesis. One of the primary advantages is that the measured signal in the form of a RAD can be analyzed in its entirety including determination of die-away times in different time domains. This capability led to the development of the early die-away method, a novel leakage multiplication determination method which is tested throughout the thesis on different sources in simulation space and fresh fuel experiments. The early die-away method is a robust, accurate, improved method of determining multiplication without the need for knowledge of the (α,n) source term. The DDSI technique and instrument are presented along with the many novel capabilities enabled by and discovered through RAD analysis. Among the new capabilities presented are the early die-away method, total plutonium content determination, and highly sensitive missing pin detection. Simulation of hundreds of different spent and fresh fuel assemblies were used to develop the analysis algorithms and the techniques were tested on a variety of spontaneous fission-driven fresh fuel assemblies at Los Alamos National Laboratory and the BeRP ball at the Nevada National Security Site. The development of the new, improved analysis and characterization methods with the DDSI instrument makes it a viable technique for implementation in a facility to meet material control and safeguards needs.« less
Micieli, Giuseppe; Martignoni, Emilia; Sandrini, Giorgio; Bono, Giorgio; Nappi, Giuseppe
Summary This paper traces the development of research and healthcare models in the field of cerebrovascular disorders at the C. Mondino National Institute of Neurology in Pavia, Italy. It starts with a description of the original experiences of Ottorino Rossi and his thesis on atherosclerosis which date back to the beginning of the last century; it then illustrates the connections between his seminal essay and the future directions followed by research in this institute, through to the development of one of the first stroke units in Italy. In this context, we examine a large range of scientific approaches, many related to cerebrovascular diseases (such as headaches) and autonomic disorders, and some of their biological and physiological markers. The originality of an approach also based on tools of advanced technology, including information technology, is emphasised, as is the importance of passion and perseverance in the pursuit of extraordinary results in what is an extremely complex and difficult field. PMID:21729590
NASA Technical Reports Server (NTRS)
Deutschmann, Julie; Bar-Itzhack, Itzhack
1997-01-01
Traditionally satellite attitude and trajectory have been estimated with completely separate systems, using different measurement data. The estimation of both trajectory and attitude for low earth orbit satellites has been successfully demonstrated in ground software using magnetometer and gyroscope data. Since the earth's magnetic field is a function of time and position, and since time is known quite precisely, the differences between the computed and measured magnetic field components, as measured by the magnetometers throughout the entire spacecraft orbit, are a function of both the spacecraft trajectory and attitude errors. Therefore, these errors can be used to estimate both trajectory and attitude. This work further tests the single augmented Extended Kalman Filter (EKF) which simultaneously and autonomously estimates spacecraft trajectory and attitude with data from the Rossi X-Ray Timing Explorer (RXTE) magnetometer and gyro-measured body rates. In addition, gyro biases are added to the state and the filter's ability to estimate them is presented.
Monitoring X-Ray Emission from X-Ray Bursters
NASA Technical Reports Server (NTRS)
Halpern, Jules P.; Kaaret, Philip
1999-01-01
The scientific goal of this project was to monitor a selected sample of x-ray bursters using data from the All-Sky Monitor (ASM) on the Rossi X-Ray Timing Explorer together with data from the Burst and Transient Source Experiment (BATSE) on the Compton Gamma-Ray Observatory to study the long-term temporal evolution of these sources in the x-ray and hard x-ray bands. The project was closely related to "Long-Term Hard X-Ray Monitoring of X-Ray Bursters", NASA project NAG5-3891, and and "Hard x-ray emission of x-ray bursters", NASA project NAG5-4633, and shares publications in common with both of these. The project involved preparation of software for use in monitoring and then the actual monitoring itself. These efforts have lead to results directly from the ASM data and also from Target of Opportunity Observations (TOO) made with the Rossi X-Ray Timing Explorer based on detection of transient hard x-ray outbursts with the ASM and BATSE.
The Attentional Boost Effect with Verbal Materials
ERIC Educational Resources Information Center
Mulligan, Neil W.; Spataro, Pietro; Picklesimer, Milton
2014-01-01
Study stimuli presented at the same time as unrelated targets in a detection task are better remembered than stimuli presented with distractors. This attentional boost effect (ABE) has been found with pictorial (Swallow & Jiang, 2010) and more recently verbal materials (Spataro, Mulligan, & Rossi-Arnaud, 2013). The present experiments…
Populations of Bactrocera oleae (Diptera: Tephritidae) and Its Parasitoids in Himalayan Asia
USDA-ARS?s Scientific Manuscript database
For a biological control program against olive fruit fly, Bactrocera oleae Rossi, olives were collected in the Himalayan foothills (China, Nepal, India, and Pakistan) to discover new natural enemies. Wild olives, Olea europaea ssp. cuspidata (Wall ex. G. Don), were sparsely distributed and fly-infes...
Populations of Bactrocera oleae (Diptera: Tephritidae) and Its Parasitoids in Himalayan Asia
USDA-ARS?s Scientific Manuscript database
For a biological control program against olive fruit fly, Bactrocera oleae Rossi, olives were collected in the Himalayan foothills (China, Nepal, India, and Pakistan) to discover new natural enemies. Wild olives, Olea europaea ssp. cuspidata (Wall ex. G. Don), were sparsely distributed and fly-infe...
The Multileveled Regulation of the Human Cholinesterase Genes and Their Protein Products
1993-09-30
s that are involved in binding and penetration of ligands. In essence , binding affinity consists of ligand penetration in addition to its binding to...J. Cell Biol. 110, 715-719. Rotundo RL, Jasmin BJ, Lee RK, Rossi SG (1992) Compartmentalization of acetylcholinesterase mENA and protein expression
Moments in the Life of a Scientist
NASA Astrophysics Data System (ADS)
Rossi, Bruno
2008-07-01
List of plates; Foreword; Preface; Prehistory; 1. Arcetri (1928-32); 2. Padua, Copenhagen, Manchester; 3. Physics of elementary particles in the Age of Innocence (1939-46); 4. Los Alamos (1943-46); 5. Cosmic rays at MIT (1946- ); 6. Physics in space; Postscript; As for me … Nora Rossi; Index.
Evidence for Doppler-Shifted Iron Emission Lines in Black Hole Candidate 4U 1630-47
NASA Technical Reports Server (NTRS)
Cui, Wei; Chen, Wan; Zhang, Shuang Nan
2000-01-01
We report the first detection of a pair of correlated the X-ray spectrum of black hole candidate 4U 1630-47 outburst, based on Rossi X-Ray Timing Explorer (RXTE) emission lines in during its 1996 observations of the source. At the peak plateau of the outburst, the emission lines are detected, centered mostly at approx. 5.7 and approx. 7.7 keV, respectively, while the line energies exhibit random variability approx. 5%. Interestingly, the lines move in a concerted manner to keep their separation roughly constant. The lines also vary greatly in strength, but with the lower energy line always much stronger than the higher energy one. The measured equivalent width ranges from approx. 50 to approx. 270 eV for the former, and from insignificant detection to approx. 140 eV for the latter; the two are reasonably correlated. The correlation between the lines implies a causal connection; perhaps they share a common origin. Both lines may arise from a single K & alpha; line of highly ionized iron that is Doppler shifted either in a Keplerian accretion disk or in a bipolar outflow or even both. In both scenarios, a change in the line energy might simply reflect a change in the ionization state of line-emitting matter. We discuss the implication of the results and also raise some questions about such interpretations.
Relativistic Iron Emission and Disk Reflection in Galactic Microquasar XTE J1748-288
NASA Technical Reports Server (NTRS)
Miller, J. M.; Fox, D. W.; Matteo, T. DI; Wijnands, R.; Belloni, T.; Pooley, D.; Kouveliotou, C.; Lewin, W. H. G.
2001-01-01
We report evidence for an Fe K(alpha) fluorescence line feature and disk reflection in the very high, high-, and low-state X-ray spectra of the Galactic microquasar XTE J1748-288 during its 1998 June outburst. Spectral analyses are made on data gathered throughout the outburst by the Rossi X-Ray Timing Explorer Proportional Counter Array. Gaussian line, relativistic disk emission line, and ionized disk reflection models are fitted to the data. In the very high state the line profile appears strongly redshifted, consistent with disk emission from the innermost stable orbits around a maximally rotating Kerr black hole. In the high state the line profile is less redshifted and increasingly prominent. The low-state line profile is very strong (approx. 0.5 keV equivalent width) and centered at 6.7 +/- 0.10 keV; disk line emission model fits indicate that the inner edge of the disk fluctuates between approx. 20Rg and approx. 100Rg in this state. The disk reflection fraction is traced through the outburst; reflection from an ionized disk is preferred in the very high and high states, and reflection from a relatively neutral disk is preferred in the low state. We discuss the implications of our findings for the binary system dynamics and accretion flow geometry in XTE J1748-288.
Relativistic Iron Emission and Disk Reflection in Galactic Microquasar XTE J1748-288
NASA Technical Reports Server (NTRS)
Miller, J. M.; Fox, D. W.; DiMatteo, T.; Wijnands, R.; Belloni, T.; Pooley, D.; Kouveliotou, C.; Lewin, W. H. G.
2001-01-01
We report evidence for an Fe K-alpha fluorescence line feature and disk reflection in the very high, high-, and low-state X-ray spectra of the Galactic microquasar XTE J1748 - 288 during its 1998 June outburst. Spectral analyses are made on data gathered throughout the outburst by the Rossi X-Ray Timing Explorer Proportional Counter Array. Gaussian line, relativistic disk emission line, and ionized disk reflection models are fitted to the data. In the very high state the line profile appears strongly redshifted, consistent with disk emission from the innermost stable orbits around a maximally rotating Kerr black hole. In the high state the line profile is less redshifted and increasingly prominent. The low-state line profile is very strong (approx. 0.5 keV equivalent width) and centered at 6.7 +/- 0.10 keV; disk line emission model fits indicate that the inner edge of the disk fluctuates between approx. 20R(sub g) and - approx. 100R(sub g) in this state. The disk reflection fraction is traced through the outburst; reflection from an ionized disk is preferred in the very high and high states, and reflection from a relatively neutral disk is preferred in the low state. We discuss the implications of our findings for the binary system dynamics and accretion flow geometry in XTE J1748 - 288.
XTE J1946+274 = GRO J1944+26: An Enigmatic Be/X-ray Binary
NASA Technical Reports Server (NTRS)
Wilson, Colleen A.; Finger, Mark H.; Coe, M. J.; Negueruela, Ignacio; Six, N. Frank (Technical Monitor)
2002-01-01
XTE J1946+274 = GRO J1944+26 is a 15.8-s Be/X-ray pulsar discovered simultaneously in 1998 September with the, Burst and Transient Source Experiment (BATSE) on the Compton Gamma Ray Observatory (CGRO) and the All-Sky Monitor (ASM) on the Rossi X-ray Timing Explorer (RXTE). Pulse timing analysis yielded an orbital period of 169.2 days, a moderate eccentricity of 0.33, and implied a mass function of 9.7 solar mass. We observed evidence for an accretion disk, a correlation between measured spin-up rate and flux, which was fitted to obtain a distance estimate of 9.2 +/- 1.0 kpc. XTE J1946+274 remained active from 1998 September - 2001 July, undergoing 13 outbursts that were not locked in orbital phase. Comparing RXTE PCA observations from the initial bright outburst in 1998 and the last pair of outburst in 2001, we found energy and intensity dependent pulse profile variations in both outbursts and hardening spectra with increasing intensity during the fainter 2001 outbursts. In 2001 July, optical H(alpha) observations indicate a density perturbation appeared in the Be disk as the X-ray outbursts ceased. We propose that the equatorial plane of the Be star is inclined with respect to the orbital plane in this system and that this inclination may produce the unusual outburst behavior of the system.
USDA-ARS?s Scientific Manuscript database
The mobility of olive fruit fly, Bactrocera oleae (Rossi), late third instars before pupation, teneral adults before flight, and mature adults restricted from flight was studied under mulches in greenhouse cage tests, in horizontal pipes, vertical bottles and pipes filled with sand, and by observati...
USDA-ARS?s Scientific Manuscript database
The olive fruit fly, Bactrocera oleae, is a highly significant pest in olive growing countries whose control may be enhanced by the use of genetically-modified strains, especially for sterile insect technique programs. To improve and expand this technology, piggyBac-mediated germline transformation ...
ERIC Educational Resources Information Center
Berk, Richard A.
2007-01-01
Peter Rossi's reputation was built on a pragmatic and careful approach to research practice. He cared most about facts: getting the facts right, and then communicating those facts in an earthy, accessible, and witty manner. At the same time, Pete had a brash interpersonal style and a taste for taking on some of the most controversial policy…
A Temperature-Dependent Phase-Field Model for Phase Separation and Damage
NASA Astrophysics Data System (ADS)
Heinemann, Christian; Kraus, Christiane; Rocca, Elisabetta; Rossi, Riccarda
2017-07-01
In this paper we study a model for phase separation and damage in thermoviscoelastic materials. The main novelty of the paper consists in the fact that, in contrast with previous works in the literature concerning phase separation and damage processes in elastic media, in our model we encompass thermal processes, nonlinearly coupled with the damage, concentration and displacement evolutions. More particularly, we prove the existence of "entropic weak solutions", resorting to a solvability concept first introduced in Feireisl (Comput Math Appl 53:461-490, 2007) in the framework of Fourier-Navier-Stokes systems and then recently employed in Feireisl et al. (Math Methods Appl Sci 32:1345-1369, 2009) and Rocca and Rossi (Math Models Methods Appl Sci 24:1265-1341, 2014) for the study of PDE systems for phase transition and damage. Our global-in-time existence result is obtained by passing to the limit in a carefully devised time-discretization scheme.
Remote Sensing Data Analytics for Planetary Science with PlanetServer/EarthServer
NASA Astrophysics Data System (ADS)
Rossi, Angelo Pio; Figuera, Ramiro Marco; Flahaut, Jessica; Martinot, Melissa; Misev, Dimitar; Baumann, Peter; Pham Huu, Bang; Besse, Sebastien
2016-04-01
Planetary Science datasets, beyond the change in the last two decades from physical volumes to internet-accessible archives, still face the problem of large-scale processing and analytics (e.g. Rossi et al., 2014, Gaddis and Hare, 2015). PlanetServer, the Planetary Science Data Service of the EC-funded EarthServer-2 project (#654367) tackles the planetary Big Data analytics problem with an array database approach (Baumann et al., 2014). It is developed to serve a large amount of calibrated, map-projected planetary data online, mainly through Open Geospatial Consortium (OGC) Web Coverage Processing Service (WCPS) (e.g. Rossi et al., 2014; Oosthoek et al., 2013; Cantini et al., 2014). The focus of the H2020 evolution of PlanetServer is still on complex multidimensional data, particularly hyperspectral imaging and topographic cubes and imagery. In addition to hyperspectral and topographic from Mars (Rossi et al., 2014), the use of WCPS is applied to diverse datasets on the Moon, as well as Mercury. Other Solar System Bodies are going to be progressively available. Derived parameters such as summary products and indices can be produced through WCPS queries, as well as derived imagery colour combination products, dynamically generated and accessed also through OGC Web Coverage Service (WCS). Scientific questions translated into queries can be posed to a large number of individual coverages (data products), locally, regionally or globally. The new PlanetServer system uses the the Open Source Nasa WorldWind (e.g. Hogan, 2011) virtual globe as visualisation engine, and the array database Rasdaman Community Edition as core server component. Analytical tools and client components of relevance for multiple communities and disciplines are shared across service such as the Earth Observation and Marine Data Services of EarthServer. The Planetary Science Data Service of EarthServer is accessible on http://planetserver.eu. All its code base is going to be available on GitHub, on https://github.com/planetserver References: Baumann, P., et al. (2015) Big Data Analytics for Earth Sciences: the EarthServer approach, International Journal of Digital Earth, doi: 10.1080/17538947.2014.1003106. Cantini, F. et al. (2014) Geophys. Res. Abs., Vol. 16, #EGU2014-3784. Gaddis, L., and T. Hare (2015), Status of tools and data for planetary research, Eos, 96, dos: 10.1029/2015EO041125. Hogan, P., 2011. NASA World Wind: Infrastructure for Spatial Data. Technical report. Proceedings of the 2nd International Conference on Computing for Geospatial Research & Applications ACM. Oosthoek, J.H.P, et al. (2013) Advances in Space Research. doi: 10.1016/j.asr.2013.07.002. Rossi, A. P., et al. (2014) PlanetServer/EarthServer: Big Data analytics in Planetary Science. Geophysical Research Abstracts, Vol. 16, #EGU2014-5149.
Porcu, Patrizia; O'Buckley, Todd K; Alward, Sarah E; Marx, Christine E; Shampine, Lawrence J; Girdler, Susan S; Morrow, A Leslie
2009-01-01
The 3alpha,5alpha- and 3alpha,5beta-reduced derivatives of progesterone, deoxycorticosterone, dehydroepiandrosterone and testosterone enhance GABAergic neurotransmission and produce inhibitory neurobehavioral and anti-inflammatory effects. Despite substantial information on the progesterone derivative (3alpha,5alpha)-3-hydroxypregnan-20-one (3alpha,5alpha-THP, allopregnanolone), the physiological significance of the other endogenous GABAergic neuroactive steroids has remained elusive. Here, we describe the validation of a method using gas chromatography-mass spectrometry to simultaneously identify serum levels of the eight 3alpha,5alpha- and 3alpha,5beta-reduced derivatives of progesterone, deoxycorticosterone, dehydroepiandrosterone and testosterone. The method shows specificity, sensitivity and enhanced throughput compared to other methods already available for neuroactive steroid quantification. Administration of pregnenolone to rats and progesterone to women produced selective effects on the 3alpha,5alpha- and 3alpha,5beta-reduced neuroactive steroids, indicating differential regulation of their biosynthetic pathways. Pregnenolone administration increased serum levels of 3alpha,5alpha-THP (+1488%, p<0.001), (3alpha,5alpha)-3,21-dihydroxypregnan-20-one (3alpha,5alpha-THDOC, +205%, p<0.01), (3alpha,5alpha)-3-hydroxyandrostan-17-one (3alpha,5alpha-A, +216%, p<0.001), (3alpha,5alpha,17beta)-androstane-3,17-diol (3alpha,5alpha-A-diol, +190%, p<0.01). (3alpha,5beta)-3-hydroxypregnan-20-one (3alpha,5beta-THP) and (3alpha,5beta)-3-hydroxyandrostan-17-one (3alpha,5beta-A) were not altered, while (3alpha,5beta)-3,21-dihydroxypregnan-20-one (3alpha,5beta-THDOC) and (3alpha,5beta,17beta)-androstane-3,17-diol (3alpha,5beta-A-diol) were increased from undetectable levels to 271+/-100 and 2.4+/-0.9 pg+/-SEM, respectively (5/8 rats). Progesterone administration increased serum levels of 3alpha,5alpha-THP (+1806%, p<0.0001), 3alpha,5beta-THP (+575%, p<0.001), 3alpha,5alpha-THDOC (+309%, p<0.001). 3alpha,5beta-THDOC levels were increased by 307%, although this increase was not significant because this steroid was detected only in 3/16 control subjects. Levels of 3alpha,5alpha-A, 3alpha,5beta-A and pregnenolone were not altered. This method can be used to investigate the physiological and pathological role of neuroactive steroids and to develop biomarkers and new therapeutics for neurological and psychiatric disorders.
USDA-ARS?s Scientific Manuscript database
Despite the peer review process, it sometimes happens that scientific papers are published that give misleading or incorrect conclusions. Scientists with the USDA-ARS Soil and Water Management Research Unit, Bushland, Texas, found that a paper on soil water sensors published in an engineering journa...
USDA-ARS?s Scientific Manuscript database
The olive fruit fly, Bactrocera oleae (Rossi) (Diptera: Tephritidae) is an important pest of olives which is worldwide distributed and responsible for economic losses of approximately US$800 million per year. Since the 2000s both economical and environmental concerns have raised interested in clas...
USDA-ARS?s Scientific Manuscript database
The invasive olive fruit fly Bactrocera oleae (Rossi) (Diptera: Tephritidae) likely originated in sub-Saharan Africa, where the wild olive Olea europaea cuspidata L. (Wall. ex G. Don) is found and from which the domesticated olive O. europaea europaea L. was derived. Following the path of olive cult...
2010-11-01
Microscopy measurements on operating Pentacene Thin Film Transistor Rossi (Brazil) Organic Vertical Field Effect Transistor using DPIF as organic...Conductors and Related Quantum Matter Oral Session OSC7 12:00-12:20 12:20-12:40 Zulkifli (Malaysia) In-situ imaging of Structural Inhomogeneity and Local Jc
Marital dissolution: an economic analysis.
Hunter, K A
1984-01-01
A longitudinal analysis of factors affecting marital dissolution in the United States is presented using data from the Coleman-Rossi Retrospective Life History. Factors considered include labor force participation of both spouses, wage growth, size of family unit, age at marriage, and educational status. The study is based on the economic analysis approach developed by Gary S. Becker and others.
2008-04-01
Gray, A.; Tolentino, A.; Jagusztyn, N.; Stilson, F.; Klein, R.; Willis , T.; Rossi, M.; Redden, E.; Elliott, L. Guiding Principles for Tactile...7290 1 COMMANDANT USAADASCH ATTN ATSA CD ATTN AMSRD ARL HR ME DR HAWLEY 5800 CARTER RD FT BLISS TX 79916-3802 NO. OF COPIES
Coefficient Alpha Bootstrap Confidence Interval under Nonnormality
ERIC Educational Resources Information Center
Padilla, Miguel A.; Divers, Jasmin; Newton, Matthew
2012-01-01
Three different bootstrap methods for estimating confidence intervals (CIs) for coefficient alpha were investigated. In addition, the bootstrap methods were compared with the most promising coefficient alpha CI estimation methods reported in the literature. The CI methods were assessed through a Monte Carlo simulation utilizing conditions…
A method to reproduce alpha-particle spectra measured with semiconductor detectors.
Timón, A Fernández; Vargas, M Jurado; Sánchez, A Martín
2010-01-01
A method is proposed to reproduce alpha-particle spectra measured with silicon detectors, combining analytical and computer simulation techniques. The procedure includes the use of the Monte Carlo method to simulate the tracks of alpha-particles within the source and in the detector entrance window. The alpha-particle spectrum is finally obtained by the convolution of this simulated distribution and the theoretical distributions representing the contributions of the alpha-particle spectrometer to the spectrum. Experimental spectra from (233)U and (241)Am sources were compared with the predictions given by the proposed procedure, showing good agreement. The proposed method can be an important aid for the analysis and deconvolution of complex alpha-particle spectra. Copyright 2009 Elsevier Ltd. All rights reserved.
Zhang, Zhiyong; Yuan, Ke-Hai
2016-06-01
Cronbach's coefficient alpha is a widely used reliability measure in social, behavioral, and education sciences. It is reported in nearly every study that involves measuring a construct through multiple items. With non-tau-equivalent items, McDonald's omega has been used as a popular alternative to alpha in the literature. Traditional estimation methods for alpha and omega often implicitly assume that data are complete and normally distributed. This study proposes robust procedures to estimate both alpha and omega as well as corresponding standard errors and confidence intervals from samples that may contain potential outlying observations and missing values. The influence of outlying observations and missing data on the estimates of alpha and omega is investigated through two simulation studies. Results show that the newly developed robust method yields substantially improved alpha and omega estimates as well as better coverage rates of confidence intervals than the conventional nonrobust method. An R package coefficientalpha is developed and demonstrated to obtain robust estimates of alpha and omega.
Shedding a New Light on the Universe: An Information and Activity Booklet. Grades 9-12.
ERIC Educational Resources Information Center
Masetti, Maggie
This activity booklet is divided into two parts. Part One presents basic information about the electromagnetic spectrum and multiwavelength astronomy with an emphasis on X-ray astronomy. Part Two describes X-ray detectors at a more advanced level. An introduction to the Rossi X-ray Timing Explorer (RXTE) and its contributions to science is…
ERIC Educational Resources Information Center
Cardon, Peter W.
2010-01-01
Instructors of intercultural business communication courses inevitably face the challenge of providing cross-cultural experiences in the classroom, and students are eager to have real exposure to other cultures. One way of simulating the feel of entering another culture is through films. As Mallinger and Rossy (2003) state, films are a "uniquely…
Examining the Effects of School-Provided E-Readers on Middle School Students' Reading Ability
ERIC Educational Resources Information Center
Brown, H. Quincy
2016-01-01
Nationwide, the increasing popularity of e-books is undeniable; sales of e-books increased an astounding 4,456% over a 5-year period. Researchers, Miranda, Johnson, and Rossi-Williams, determined that e-readers have a positive impact on students' desire to read. This study attempted to determine if the use of institution issued e-readers would…
Why is Southern African canine babesiosis so virulent? An evolutionary perspective.
Penzhorn, Barend L
2011-04-13
Canine babesiosis is a common, highly virulent disease in Southern Africa with even pups and juveniles being severely affected. This contrasts with bovine babesiosis, for example, where host, parasite and vector co-evolved and young animals develop immunity after infection without showing clinical signs. Babesia rossi, the main causative organism of canine babesiosis in sub-Saharan Africa, was first described from a side-striped jackal (Canis adustus) in Kenya. Although data are meagre, there is evidence that indigenous African canids, such as jackals and wild dogs (Lycaon pictus), can harbour the parasite without showing untoward effects. Dogs are not indigenous to Africa. The vast majority of dogs presented at veterinary facilities in South Africa represent recently introduced European, Asian or American breeds. The contention is that B. rossi is a new challenge to which these dogs have not adapted. With intensive treatment of clinical cases, natural selection is effectively negated and the status quo will probably be maintained indefinitely. It is postulated that Babesia vogeli, which frequently results in unapparent infections or mild manifestations in dogs, represents or is closely related to the ancestral form of the canine parasite, possibly originating from wolves (Canis lupus).
Why is Southern African canine babesiosis so virulent? An evolutionary perspective
2011-01-01
Canine babesiosis is a common, highly virulent disease in Southern Africa with even pups and juveniles being severely affected. This contrasts with bovine babesiosis, for example, where host, parasite and vector co-evolved and young animals develop immunity after infection without showing clinical signs. Babesia rossi, the main causative organism of canine babesiosis in sub-Saharan Africa, was first described from a side-striped jackal (Canis adustus) in Kenya. Although data are meagre, there is evidence that indigenous African canids, such as jackals and wild dogs (Lycaon pictus), can harbour the parasite without showing untoward effects. Dogs are not indigenous to Africa. The vast majority of dogs presented at veterinary facilities in South Africa represent recently introduced European, Asian or American breeds. The contention is that B. rossi is a new challenge to which these dogs have not adapted. With intensive treatment of clinical cases, natural selection is effectively negated and the status quo will probably be maintained indefinitely. It is postulated that Babesia vogeli, which frequently results in unapparent infections or mild manifestations in dogs, represents or is closely related to the ancestral form of the canine parasite, possibly originating from wolves (Canis lupus). PMID:21489239
Experience Gained From Launch and Early Orbit Support of the Rossi X-Ray Timing Explorer (RXTE)
NASA Technical Reports Server (NTRS)
Fink, D. R.; Chapman, K. B.; Davis, W. S.; Hashmall, J. A.; Shulman, S. E.; Underwood, S. C.; Zsoldos, J. M.; Harman, R. R.
1996-01-01
this paper reports the results to date of early mission support provided by the personnel of the Goddard Space Flight Center Flight Dynamics Division (FDD) for the Rossi X-Ray Timing Explorer (RXTE) spacecraft. For this mission, the FDD supports onboard attitude determination and ephemeris propagation by supplying ground-based orbit and attitude solutions and calibration results. The first phase of that support was to provide launch window analyses. As the launch window was determined, acquisition attitudes were calculated and calibration slews were planned. postlaunch, these slews provided the basis for ground determined calibration. Ground determined calibration results are used to improve the accuracy of onboard solutions. The FDD is applying new calibration tools designed to facilitate use of the simultaneous, high-accuracy star observations from the two RXTE star trackers for ground attitude determination and calibration. An evaluation of the performance of these tools is presented. The FDD provides updates to the onboard star catalog based on preflight analysis and analysis of flight data. The in-flight results of the mission support in each area are summarized and compared with pre-mission expectations.
{alpha}+{sup 6,8}He resonant scattering and exotic structures in {sup 10,12}Be
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ito, Makoto; Itagaki, Naoyuki
2008-05-21
The {alpha}+{sup 6}He low-energy reactions and the structural changes of {sup 10}Be in the microscopic {alpha}+{alpha}+2N model are studied by the generalized two-center cluster model with the Kohn-Hulthen-Kato variation method. It is found that, in the inelastic scattering to the {alpha}+{sup 6}He(2{sub 1}{sup +}) channel, characteristic enhancements are expected as the results of the parity-dependent non-adiabatic dynamics. The similar method is applied to the resonant scattering of {alpha}+{sup 8}He, and the coupling with the compound configurations of {alpha}+{alpha}+4N are discussed.
Chen, Jian; Luo, Bi; Qi, Zhu; Huo, Pei-Dan; Zhang, Quan-Sheng; Wang, Hong
2010-06-01
This study was aimed to establish a method of PCR combination with PCR-RFLP for detecting the South-East Asian (SEA) deletion type alpha-thalassemia 1 and non-deletion mutation of Hb Constant Spring (CS), and to investigate the application value of this method. For the members of the families with alpha-thalassemia, SEA deletion mutation was detected by PCR, then the HbCS point mutation was screened by PCR-RFLP. The results indicated that 15 carriers with alpha-thalassemia (--(SEA)/) were found in 19 members from 7 families, and 2 families with genotype of --(SEA)/alpha(CS)alpha were screened out successfully. It is concluded that the PCR combination with PCR-RFLP is a simple, rapid, and reliable method for screening HbH disease with genotype of --(SEA)/alpha(CS)alpha.
Polynomial complexity despite the fermionic sign
NASA Astrophysics Data System (ADS)
Rossi, R.; Prokof'ev, N.; Svistunov, B.; Van Houcke, K.; Werner, F.
2017-04-01
It is commonly believed that in unbiased quantum Monte Carlo approaches to fermionic many-body problems, the infamous sign problem generically implies prohibitively large computational times for obtaining thermodynamic-limit quantities. We point out that for convergent Feynman diagrammatic series evaluated with a recently introduced Monte Carlo algorithm (see Rossi R., arXiv:1612.05184), the computational time increases only polynomially with the inverse error on thermodynamic-limit quantities.
Assessing Post Conflict State Building Efforts
2013-03-01
Develop a global partnership for development Target: Develop further an open, rule-based, predictable, non-discriminatory trading and finance system...Beginner’s Guide to Nation-Building (Santa Monica, CA: Rand Corporation ), 2007, xvii. 15 Samuel Berger, Brent Scowcroft, and William L. Nash, “In...The Beginner’s Guide, xxi. 25 Richard A. Berk and Peter H. Rossi, Thinking About Program Evaluation 2, (Thousand Oaks, CA: Sage Publications, 1999
Quasi-periodic Pulse Amplitude Modulation in the Accreting Millisecond Pulsar IGR J00291+5934
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bult, Peter; Doesburgh, Marieke van; Klis, Michiel van der
We introduce a new method for analyzing the aperiodic variability of coherent pulsations in accreting millisecond X-ray pulsars (AMXPs). Our method involves applying a complex frequency correction to the time-domain light curve, allowing for the aperiodic modulation of the pulse amplitude to be robustly extracted in the frequency domain. We discuss the statistical properties of the resulting modulation spectrum and show how it can be correlated with the non-pulsed emission to determine if the periodic and aperiodic variability are coupled processes. Using this method, we study the 598.88 Hz coherent pulsations of the AMXP IGR J00291+5934 as observed with themore » Rossi X-ray Timing Explorer and XMM-Newton . We demonstrate that our method easily confirms the known coupling between the pulsations and a strong 8 mHz quasi-periodic oscillation (QPO) in XMM-Newton observations. Applying our method to the RXTE observations, we further show, for the first time, that the much weaker 20 mHz QPO and its harmonic are also coupled with the pulsations. We discuss the implications of this coupling and indicate how it may be used to extract new information on the underlying accretion process.« less
Quasi-Periodic Pulse Amplitude Modulation in the Accreting Millisecond Pulsar IGR J00291+5934
NASA Technical Reports Server (NTRS)
Bult, Peter; van Doesburgh, Marieke; van der Klis, Michiel
2017-01-01
We introduce a new method for analyzing the a periodic variability of coherent pulsations in accreting millisecond X-ray pulsars (AMXPs). Our method involves applying a complex frequency correction to the time-domain lightcurve, allowing for the aperiodic modulation of the pulse amplitude to be robustly extracted in the frequency domain. We discuss the statistical properties of the resulting modulation spectrum and show how it can be correlated with the non-pulsed emission to determine if the periodic and a periodic variability are coupled processes. Using this method, we study the 598.88 Hz coherent pulsations of the AMXP IGR J00291+5934 as observed with the Rossi X-ray Timing Explorer and XMM-Newton. We demonstrate that our method easily confirms the known coupling between the pulsations and a strong 8 mHz quasi-periodic oscillation (QPO) in XMM-Newton observations. Applying our method to the RXTE observations, we further show, for the first time, that the much weaker 20 mHz QPO and its harmonic are also coupled with the pulsations. We discuss the implications of this coupling and indicate how it may be used to extract new information on the underlying accretion process.
Tick-borne haemoparasites and Anaplasmataceae in domestic dogs in Zambia.
Qiu, Yongjin; Kaneko, Chiho; Kajihara, Masahiro; Ngonda, Saasa; Simulundu, Edgar; Muleya, Walter; Thu, May June; Hang'ombe, Mudenda Bernard; Katakura, Ken; Takada, Ayato; Sawa, Hirofumi; Simuunza, Martin; Nakao, Ryo
2018-05-01
Tick-borne diseases (TBDs), including emerging and re-emerging infectious diseases, are important threats to human and animal health worldwide. Indeed, the number of reported human and animal infectious cases of novel TBD agents has increased in recent decades. However, TBDs tend to be neglected, especially in resource-limited countries that often have limited diagnostic capacity. The aim of this molecular survey was to detect and characterise tick-borne pathogens (Babesia, Theileria, and Hepatozoon parasites and Anaplasmataceae bacteria) in domestic dogs in Zambia. In total, 247 canine peripheral blood samples were collected in Lusaka, Mazabuka, Monze, and Shangombo. Conventional PCR to detect the selected pathogens was performed using DNA extracted from canine blood. One hundred eleven samples were positive for protozoa and 5 were positive for Anaplasmataceae. Sequencing of thirty-five randomly selected protozoa-positive samples revealed the presence of Babesia rossi, Babesia vogeli, and Hepatozoon canis 18S rDNA. Based on these sequences, a multiplex PCR system was developed to yield PCR products with different amplicons, the size of which depended on the parasite species; thus, each species could be identified without the need for sequence analysis. Approximately 40% of dogs were positive for H. canis. In particular, the positive rate (75.2%) of H. canis infection was significantly higher in Shangombo than in other sampling sites. Multiplex PCR assay detected B. rossi and B. vogeli infections in five and seven dogs, respectively, indicating that this approach is useful for detecting parasites with low prevalence. Sequencing analysis of gltA and groEL genes of Anaplasmataceae revealed that two and one dogs in Lusaka were infected with Anaplasma platys and Ehrlichia canis, respectively. The data indicated that Zambian dogs were infected with multiple tick-borne pathogens such as H. canis, B. rossi, B. vogeli, A. platys, E. canis and uncharacterized Ehrlichia sp. Since some of these parasites are zoonotic, concerted efforts are needed to raise awareness of, and control, these tick-borne pathogens. Copyright © 2018 Elsevier GmbH. All rights reserved.
Methods for the synthesis and polymerization of .alpha.,.alpha.'-dihalo-p-xylenes
Ferraris, John P.; Neef, Charles J.
2002-07-30
The present invention describes an improved method for the polymerization of .alpha.,.alpha.-dihalo-p-xylene's such as the .alpha.,.alpha.'-dihalo-2-methoxy-5-(2-ethylhexyloxy)-xylene's. The procedure for synthesis is based on the specific order of addition of reagents and the use of an anionic initiator that allows control of the molecular weight of the polymer. The molecular weight control allows processability of the polymer which is important for its utility in applications including in light-emitting-diodes, field effect transistors and photovoltaic devices.
Method for detecting the presence of prostate cancer
Karin, Michael; Luo, Jun-Li; Tan, Wei
2010-04-13
The present invention relates to compositions and methods for cancer diagnosis, treatment and drug screening. In particular, the present invention provides compositions and methods for targeting the nuclear translocation of IkB kinase-.alpha. (IKK.alpha.) and the IKK.alpha.-mediated suppression of Maspin expression observed in metastatic prostate cancer cells.
NASA Astrophysics Data System (ADS)
Grigoryan, Artyom M.; John, Aparna; Agaian, Sos S.
2017-03-01
2-D quaternion discrete Fourier transform (2-D QDFT) is the Fourier transform applied to color images when the color images are considered in the quaternion space. The quaternion numbers are four dimensional hyper-complex numbers. Quaternion representation of color image allows us to see the color of the image as a single unit. In quaternion approach of color image enhancement, each color is seen as a vector. This permits us to see the merging effect of the color due to the combination of the primary colors. The color images are used to be processed by applying the respective algorithm onto each channels separately, and then, composing the color image from the processed channels. In this article, the alpha-rooting and zonal alpha-rooting methods are used with the 2-D QDFT. In the alpha-rooting method, the alpha-root of the transformed frequency values of the 2-D QDFT are determined before taking the inverse transform. In the zonal alpha-rooting method, the frequency spectrum of the 2-D QDFT is divided by different zones and the alpha-rooting is applied with different alpha values for different zones. The optimization of the choice of alpha values is done with the genetic algorithm. The visual perception of 3-D medical images is increased by changing the reference gray line.
Zhang, Zhiyong; Yuan, Ke-Hai
2015-01-01
Cronbach’s coefficient alpha is a widely used reliability measure in social, behavioral, and education sciences. It is reported in nearly every study that involves measuring a construct through multiple items. With non-tau-equivalent items, McDonald’s omega has been used as a popular alternative to alpha in the literature. Traditional estimation methods for alpha and omega often implicitly assume that data are complete and normally distributed. This study proposes robust procedures to estimate both alpha and omega as well as corresponding standard errors and confidence intervals from samples that may contain potential outlying observations and missing values. The influence of outlying observations and missing data on the estimates of alpha and omega is investigated through two simulation studies. Results show that the newly developed robust method yields substantially improved alpha and omega estimates as well as better coverage rates of confidence intervals than the conventional nonrobust method. An R package coefficientalpha is developed and demonstrated to obtain robust estimates of alpha and omega. PMID:29795870
Jha, Vishwajeet; Kondekar, Nagendra B; Kumar, Pradeep
2010-06-18
A novel and general method for asymmetric synthesis of both syn/anti-1,3-amino alcohols is described. The method uses proline-catalyzed sequential alpha-aminoxylation/ alpha-amination and Horner-Wadsworth-Emmons (HWE) olefination of aldehydes as the key step. By using this method, a short synthesis of a bioactive molecule, (R)-1-((S)-1-methylpyrrolidin-2-yl)-5-phenylpentan-2-ol, is also accomplished.
The Search for Quality by Management in Service-Related Industry Today
1988-09-05
service delivery. Rossy, Gerard L. ’The Executive’s Role in Ethics: The View from Business and Industry.* Healthcare Executive 2 (September/October...to study and compare: h-spitality, pharmaceutical, and healthcare . The hospitality industry was identified due to the dependence upon the consumer. If...only regulatory requirements, but a social obligation. The healthcare industry was chosen due to the need for quality, the increased competition, and
Annual Surveillance Summary: Klebsiella Infections in the Military Health System (MHS), 2015
2017-03-01
EDC-TR-190-2017 By Kristen Rossi and Uzo Chukwuma EpiData Center Department Prepared March 2017 Approved for public release. Distribution is...treatments to combat them, resulting in wide-ranging global public health implications.4 Furthermore, bacteria with carbapenem-resistant genes...Prepared March 2017 EpiData Center Department NMCPHC-EDC-TR-190-2017 In 2001, Jones et al. reported that nosocomial infections account for more than
Normal and Differential SAR Interferometry
2005-02-01
incorporating the use of a rough DEM. [ Adragna 1995]. The same technique is also used for flat Earth removal, and for differential interferometry (Cap.5...and F. Adragna , 1994. Radar Interferometric Mapping of Deformation in the Year After the Landers Earthquake, Nature, Vol. 369, pp. 227-230 Massonnet...D., M. Rossi, C. Carmona, F. Adragna , G. Peltzer, K. Feigi, and T. Rabaute, 1993. The Displacement Field of the Landers Earthquake Mapped by Radar
A Species Distribution Modeling Informed Conservation Assessment of Bog Spicebush
2016-09-14
small populations, or establishing new popu- lations to increase the metapopulation structure within clusters of popula- tions. These outplanting data...fire suppression, and flooding (e.g., due to beaver activity) on vege- tation composition and structure . This effort used vegetation and disturb- ance...Suppression to Prescription. Tall Timbers Research Station, Tallahassee, FL, pp 70–81. Godefroid, S., C. Piazza, G. Rossi, S. Buord, A. D. Stevens, R
NASA Technical Reports Server (NTRS)
1995-01-01
In this photograph, Sandra Rossi user her NASA-developed prosthesis for the first time. Derived from foam insulation technology used to protect the Space Shuttle External Tank from excessive heat, FAB/CAD, a subsidiary of the Harshberger Prosthetic and Orthotic Center, utilized the technology to replace the heavy, fragile plaster they used to produce master molds for prosthetics. The new material was lighter, cheaper and easier to manufacture than plaster, resulting in lower costs to the customer.
Temporal Variations of Strength and Location of the South Atlantic Anomaly as Measured by RXTE
NASA Technical Reports Server (NTRS)
Wilms, Jorn; Felix, Furst; Rothschild, Richard E.; Pottschmidt, Katja; Smith, David M.; Lingenfelter, Richard
2009-01-01
The evolution of the particle background at an altitude of approx.540km during the time interval between 1996 and 2007 is studied using the particle monitor of the High Energy X-ray Timing Experiment on board NASA's Rossi X-ray Timing Explorer. A special emphasis of this study is the location and strength of the South Atlantic Anomaly (SAA). The size and strength of the SAA are anti-correlated with the the 10.7 cm radio flux of the Sun, which leads the SAA strength by approx.1 year reflecting variations in solar heating of the upper atmosphere. The location of the SAA is also found to drift westwards with an average drift rate of about 0.3deg/yr following the drift of the geomagnetic field configuration. Superimposed to this drift rate are irregularities, where the SAA suddenly moves eastwards and where furthermore the speed of the drift changes. The most prominent of these irregularities is found in the second quarter of 2003 and another event took place in 1999. We suggest that these events are previously unrecognized manifestations of the geomagnetic jerks of the Earth's magnetic field. Key words: space radiation environment, South Atlantic Anomaly, radiation monitors, Rossi X-ray Timing Explorer
Detection of alpha radiation in a beta radiation field
Mohagheghi, Amir H.; Reese, Robert P.
2001-01-01
An apparatus and method for detecting alpha particles in the presence of high activities of beta particles utilizing an alpha spectrometer. The apparatus of the present invention utilizes a magnetic field applied around the sample in an alpha spectrometer to deflect the beta particles from the sample prior to reaching the detector, thus permitting detection of low concentrations of alpha particles. In the method of the invention, the strength of magnetic field required to adequately deflect the beta particles and permit alpha particle detection is given by an algorithm that controls the field strength as a function of sample beta energy and the distance of the sample to the detector.
Kellie, John F; Higgs, Richard E; Ryder, John W; Major, Anthony; Beach, Thomas G; Adler, Charles H; Merchant, Kalpana; Knierman, Michael D
2014-07-23
A robust top down proteomics method is presented for profiling alpha-synuclein species from autopsied human frontal cortex brain tissue from Parkinson's cases and controls. The method was used to test the hypothesis that pathology associated brain tissue will have a different profile of post-translationally modified alpha-synuclein than the control samples. Validation of the sample processing steps, mass spectrometry based measurements, and data processing steps were performed. The intact protein quantitation method features extraction and integration of m/z data from each charge state of a detected alpha-synuclein species and fitting of the data to a simple linear model which accounts for concentration and charge state variability. The quantitation method was validated with serial dilutions of intact protein standards. Using the method on the human brain samples, several previously unreported modifications in alpha-synuclein were identified. Low levels of phosphorylated alpha synuclein were detected in brain tissue fractions enriched for Lewy body pathology and were marginally significant between PD cases and controls (p = 0.03).
Selective flow path alpha particle detector and method of use
Orr, Christopher Henry; Luff, Craig Janson; Dockray, Thomas; Macarthur, Duncan Whittemore
2002-01-01
A method and apparatus for monitoring alpha contamination are provided in which ions generated in the air surrounding the item, by the passage of alpha particles, are moved to a distant detector location. The parts of the item from which ions are withdrawn can be controlled by restricting the air flow over different portions of the apparatus. In this way, detection of internal and external surfaces separately, for instance, can be provided. The apparatus and method are particularly suited for use in undertaking alpha contamination measurements during the commissioning operations.
Giroussi, S; Voulgaropoulos, A; Ayiannidis, A K; Golimowski, J; Janicki, M
1995-12-22
A selective and sensitive voltammetric method for the determination of cobalt in vegetable animal foodstuffs is developed. The method is based on the use of alpha-benzil dioxime (alpha-BD) as a chelating agent for differential pulse adsorptive stripping voltammetry (DPASV) and is free from zinc interferences. The influence of pH, time and alpha-BD concentration on the peak resolution and height are discussed. The method was successfully applied in some typical vegetable animal foodstuffs with R.S.D. < 6%.
Offenberg, John H; Lewis, Charles W; Lewandowski, Michael; Jaoui, Mohammed; Kleindienst, Tadeusz E; Edney, Edward O
2007-06-01
An organic tracer method, recently proposed for estimating individual contributions of toluene and alpha-pinene to secondary organic aerosol (SOA) formation, was evaluated by conducting a laboratory study where a binary hydrocarbon mixture, containing the anthropogenic aromatic hydrocarbon, toluene, and the biogenic monoterpene, alpha-pinene, was irradiated in air in the presence of NO(x) to form SOA. The contributions of toluene and alpha-pinene to the total SOA concentration, calculated using the organic tracer method, were compared with those obtained with a more direct 14C content method. In the study, SOA to SOC ratios of 2.07 +/- 0.08 and 1.41 +/- 0.04 were measured for toluene and (alpha-pinene SOA, respectively. The individual tracer-based SOA contributions of 156 microg m(-3) for toluene and 198 microg m(-)3 for alpha-pinene, which together accounted for 82% of the gravimetrically determined total SOA concentration, compared well with the 14C values of 182 and 230 microg m(-3) measured for the respective SOA precursors. While there are uncertainties associated with the organic tracer method, largely due to the chemical complexity of SOA forming chemical mechanisms, the results of this study suggest the organic tracer method may serve as a useful tool for determining whether a precursor hydrocarbon is a major SOA contributor.
XTE J1946+274 = GRO J1944+26: An Enigmatic Be/X-Ray Binary
NASA Technical Reports Server (NTRS)
Wilson, Colleen A.; Finger, Mark H.; Coe, M. J.; Negueruela, Ignacio
2003-01-01
XTE J1946+274 = GRO J1944+26 is a 15.8 s Be/X-ray pulsar discovered simultaneously in 1998 September with the Burst and Transient Source Experiment (BATSE) on the Compton Gamma Ray Observatory (CGRO) and the All-Sky Monitor (ASM) on the Rossi X-Ray Timing Explorer (RXTE). Here we present new results from BATSE and RXTE including a pulse timing analysis, spectral analysis, and evidence for an accretion disk. Our pulse timing analysis yielded an orbital period of 169.2 days, a moderate eccentricity 0.33, and implied a mass function of 9.7 solar masses. We observed evidence for an accretion disk, a correlation between measured spin-up rate and flux, which was fitted to obtain a distance estimate of 9.5 +/- 2.9 kpc. XTE J1946+274 remained active from 1998 September to 2001 July, undergoing 13 outbursts that were not locked in orbital phase. Comparing RXTE Proportional Counter Array observations from the initial bright outburst in 1998 and the last pair of outbursts in 2001, we found energy and intensity-dependent pulse profile variations in both outbursts and hardening spectra with increasing intensity during the fainter 2001 outbursts. In 2001 July, optical H alpha observations indicated that a density perturbation appeared in the Be disk as the X-ray outbursts ceased. We propose that the equatorial plane of the Be star is inclined with respect to the orbital plane in this system and that this inclination may be a factor in the unusual outburst behavior of the system.
The Faint "Heartbeats" of IGR J17091-3624: An Exceptional Black Hole Candidate
NASA Technical Reports Server (NTRS)
Altamirano, D.; Belloni, T.; Linares, M.; VanDerKlis, M.; Wunands, R.; Curran, P. A.; Kalamkar, M.; Stiele, H.; Motta, S.; Munoz-Darias, T.;
2011-01-01
We report on the first 180 days of Rossi X-Ray Timing Explorer observations of the outburst of the black hole candidate IGR Jl7091-3624. This source exhibits a broad variety of complex light curve patterns including periods of strong flares alternating with quiet intervals. Similar patterns in the X-ray light curves have been seen in the (up to now) unique black hole system GRS 1915+105. In the context of the variability classes defined by Belloni et al. for GRS 1915+105, we find that JGR J17091-3624 shows the nu, rho, alpha, lambda, Beta, and mu classes as well as quiet periods which resemble the chi class, all occurring at 2-60 keY count rate levels which can be 10-50 times lower than observed in GRS 1915+\\05. The so-called rho class "heartbeats" occur as fast as every few seconds and as slow as approx 100 s, tracing a loop in the hardness-intensity diagram which resembles that previously seen in GRS 1915+\\05. However, while GRS 1915+105 traverses this loop clockwise, IGR Jl7091-3624 does so in the opposite sense. We briefly discuss our findings in the context of the models proposed for GRS 1915+105 and find that either all models requiring near Eddington luminosities for GRS 1915+105-like variability fail, or IGR Il7091-3624 lies at a distance well in excess of 20 kpc, or it harbors one of the least massive black holes known( <3 solar M).
Kurosaki, Hiromu; Mueller, Rebecca J.; Lambert, Susan B.; ...
2016-07-15
An alternate method of preparing actinide alpha counting sources was developed in place of electrodeposition or lanthanide fluoride micro-precipitation. The method uses lanthanide hydroxide micro-precipitation to avoid the use of hazardous hydrofluoric acid. Lastly, it provides a quicker, simpler, and safer way of preparing actinide alpha counting sources in routine, production-type laboratories that process many samples daily.
Timing and Spectral Study of 4U 1538-52
NASA Technical Reports Server (NTRS)
Clark, George W.
2000-01-01
Improved orbital parameters of the high-mass binary X-ray pulsar 4U 1538-52 have been derived from high count rate data obtained from the Rossi X-Ray Timing Explorer. Pulse-timing analysis yields an eccentricity of 0.174 +/- 0.015, a periastron at 64 deg +/- 9 deg, and evidence of orbital decay with prime-P(sub orb)/P(sub orb) = (-2.9 +/- 2.1) x 10(exp -6)/yr.
2017-03-01
REPORT DOCUMENTATION PAGE Form Approved OMB No. 0704-0188 The public reporting burden for this collection of information is estimated to average 1...AUTHOR(S) Keith Hauret and Dr. Bruce Jones (Army Public Health Center) Cindy Bush, Steve Rossi, and Melissa Richardson (contractors for the Armed Forces...ORGANIZATION NAME(S) AND ADDRESS(ES) Army Public Health Center, Clinical Public Health and Epidemiology Directorate, Injury Prevention Division; Aberdeen
1995-01-01
In this photograph, Sandra Rossi user her NASA-developed prosthesis for the first time. Derived from foam insulation technology used to protect the Space Shuttle External Tank from excessive heat, FAB/CAD, a subsidiary of the Harshberger Prosthetic and Orthotic Center, utilized the technology to replace the heavy, fragile plaster they used to produce master molds for prosthetics. The new material was lighter, cheaper and easier to manufacture than plaster, resulting in lower costs to the customer.
2017-06-29
Accurate Virus Quantitation Using a Scanning Transmission Electron Microscopy (STEM) Detector in a Scanning Electron Microscope Candace D Blancett1...L Norris2, Cynthia A Rossi4 , Pamela J Glass3, Mei G Sun1,* 1 Pathology Division, United States Army Medical Research Institute of Infectious...Diseases (USAMRIID), 1425 Porter Street, Fort Detrick, Maryland, 21702 2Biostatistics Division, United States Army Medical Research Institute of
Toward Meaningful Military Compensation Reform: Research in Support of DoD’s Review
2014-01-01
CARE INFRASTRUCTURE AND TRANSPORTATION INTERNATIONAL AFFAIRS LAW AND BUSINESS NATIONAL SECURITY POPULATION AND AGING PUBLIC SAFETY SCIENCE AND...have highlighted the advantages of a hybrid plan for achieving these objectives. For example, the Defense Science Board Task Force on Human...Compensation, as well as the input of Patricia Mulcahy. We are grateful to Joel Sitrin, Chief Actuary , and Peter Rossi and Peter Zouras of the DoD Office of
2012-11-28
Simulation Sciences Branch, United States Army Research Laboratory , Aberdeen Proving Ground, Maryland, United States of America Abstract To identify...culture and may support filovirus stock standardization for medical countermeasure development. Citation: Kugelman JR, Lee MS, Rossi CA, McCarthy SE...support filovirus stock standardization for medical countermeasure development. 15. SUBJECT TERMS 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF
Itoh, Y; Tsuji, K; Tanaka, N; Yamada, M; Nakanishi, M; Ishihara, M; Kobayashi, M
1983-01-01
Thrombolytic therapy with Urokinase (UK) has often been successful but it is very difficult to determine the effective dosage of UK. It is reported that after UK administration, plasmin fibrinolytic activity was immediately inhibited by alpha 2-Plasmin inhibitor (alpha 2-PI). In this study, we used UK on patients with myoma to prevent the occurrence of thrombosis after operation and the initial decrease in alpha 2-PI activities following UK administration was investigated to determine the minimum effective dosage of UK required to suppress alpha 2-PI. An attempt was also made to measure UK activity in blood by means of chromogenic substrate S-2444, and in some cases by administering 60,000 I.U. UK, alpha 1-Antitrypsin (alpha 1-AT), alpha 2-Macroglobulin (alpha 2-M), Antithrombin III (AT III) and Plasminogen (Plg) were measured at the same time. The results were as follows: 1) By the drip infusion method. In all doses, alpha 2-PI and UK activity showed no remarkable change. 2) By the one shot method. a) A decrease in alpha 2-PI was observed following both 48,000 and 60,000 I.U. UK administration. It was noted that in the case of 48,000 I.U. UK, alpha 2-PI showed the lowest level, 60% of the pre-administration level. b) UK activity showed a gradual increase in the case of 60,000 I.U. UK only and large changes in the other cases. c) alpha 1-AT, alpha 2-M, AT III and Plg produced no remarkable changes. This indicated that the effective dosage of UK for suppressing alpha 2-PI was at least 48,000 I.U. UK with the one shot method, and alpha 2-PI is a reliable indicator of the effectiveness of UK therapy.
Reverse-phase HPLC analysis of human alpha crystallin.
Swamy, M S; Abraham, E C
1991-03-01
A rapid and highly sensitive reverse-phase HPLC (RP-HPLC) method was used to separate crystallin subunits from human alpha crystallin. Three distinct peaks were separated; by electrophoretic and immunological analyses the first and second peaks were identified as alpha B and alpha A respectively. On the other hand, peak 3 appeared to be a modified form of alpha crystallin. The ratio of alpha A and alpha B proteins was 3:1 in 1 day old lenses which gradually changed to 2:1 in 17 year old lenses and to 1:1 in the 50 and 82 year old whole lenses and 82 year old lens cortex, with a concomitant increase in the modified alpha, suggesting that alpha A subunits are relatively more involved in aggregation. Analysis of the 82 year old lens nucleus also supported this conclusion. The RP-HPLC analysis of the HMW aggregate fraction showed substantial enrichment of the modified alpha. The alpha A and alpha B subunits independently reassociated to form polymeric alpha crystallin whereas the modified alpha reassociated to form HMW aggregates as shown by molecular sieve HPLC. Hence it appears that the HMW aggregate peak was constituted by modified alpha crystallin. Only in the peak 3 material the 280 nm absorbance was about 2-fold higher than what was expected from the actual protein content. The data suggest that the changes induced by post-translational modifications may have some role in the formation of modified alpha. The present RP-HPLC method is useful in separating these modified alpha from the unmodified alpha A and alpha B subunits.
An Efficient Algorithm for the Detection of Infrequent Rapid Bursts in Time Series Data
NASA Astrophysics Data System (ADS)
Giles, A. B.
1997-01-01
Searching through data for infrequent rapid bursts is a common requirement in many areas of scientific research. In this paper, we present a powerful and flexible analysis method that, in a single pass through the data, searches for statistically significant bursts on a set of specified short timescales. The input data are binned, if necessary, and then quantified in terms of probabilities rather than rates or ratios. Using a measure-like probability makes the method relatively count rate independent. The method has been made computationally efficient by the use of lookup tables and cyclic buffers, and it is therefore particularly well suited to real-time applications. The technique has been developed specifically for use in an X-ray astronomy application to search for millisecond bursts from black hole candidates such as Cyg X-1. We briefly review the few observations of these types of features reported in the literature, as well as the variety of ways in which their statistical reliability was challenged. The developed technique, termed the burst expectation search (BES) method, is illustrated using some data simulations and archived data obtained during ground testing of the proportional counter array (PCA) experiment detectors on the Rossi X-Ray Timing Explorer (RXTE). A potential application for a real-time BES method on board RXTE is also examined.
Wickering, Ellis; Gaspard, Nicolas; Zafar, Sahar; Moura, Valdery J; Biswal, Siddharth; Bechek, Sophia; OʼConnor, Kathryn; Rosenthal, Eric S; Westover, M Brandon
2016-06-01
The purpose of this study is to evaluate automated implementations of continuous EEG monitoring-based detection of delayed cerebral ischemia based on methods used in classical retrospective studies. We studied 95 patients with either Fisher 3 or Hunt Hess 4 to 5 aneurysmal subarachnoid hemorrhage who were admitted to the Neurosciences ICU and underwent continuous EEG monitoring. We implemented several variations of two classical algorithms for automated detection of delayed cerebral ischemia based on decreases in alpha-delta ratio and relative alpha variability. Of 95 patients, 43 (45%) developed delayed cerebral ischemia. Our automated implementation of the classical alpha-delta ratio-based trending method resulted in a sensitivity and specificity (Se,Sp) of (80,27)%, compared with the values of (100,76)% reported in the classic study using similar methods in a nonautomated fashion. Our automated implementation of the classical relative alpha variability-based trending method yielded (Se,Sp) values of (65,43)%, compared with (100,46)% reported in the classic study using nonautomated analysis. Our findings suggest that improved methods to detect decreases in alpha-delta ratio and relative alpha variability are needed before an automated EEG-based early delayed cerebral ischemia detection system is ready for clinical use.
NASA Astrophysics Data System (ADS)
Shen, Wenxian
2017-09-01
This paper is concerned with the stability of transition waves and strictly positive entire solutions of random and nonlocal dispersal evolution equations of Fisher-KPP type with general time and space dependence, including time and space periodic or almost periodic dependence as special cases. We first show the existence, uniqueness, and stability of strictly positive entire solutions of such equations. Next, we show the stability of uniformly continuous transition waves connecting the unique strictly positive entire solution and the trivial solution zero and satisfying certain decay property at the end close to the trivial solution zero (if it exists). The existence of transition waves has been studied in Liang and Zhao (2010 J. Funct. Anal. 259 857-903), Nadin (2009 J. Math. Pures Appl. 92 232-62), Nolen et al (2005 Dyn. PDE 2 1-24), Nolen and Xin (2005 Discrete Contin. Dyn. Syst. 13 1217-34) and Weinberger (2002 J. Math. Biol. 45 511-48) for random dispersal Fisher-KPP equations with time and space periodic dependence, in Nadin and Rossi (2012 J. Math. Pures Appl. 98 633-53), Nadin and Rossi (2015 Anal. PDE 8 1351-77), Nadin and Rossi (2017 Arch. Ration. Mech. Anal. 223 1239-67), Shen (2010 Trans. Am. Math. Soc. 362 5125-68), Shen (2011 J. Dynam. Differ. Equ. 23 1-44), Shen (2011 J. Appl. Anal. Comput. 1 69-93), Tao et al (2014 Nonlinearity 27 2409-16) and Zlatoš (2012 J. Math. Pures Appl. 98 89-102) for random dispersal Fisher-KPP equations with quite general time and/or space dependence, and in Coville et al (2013 Ann. Inst. Henri Poincare 30 179-223), Rawal et al (2015 Discrete Contin. Dyn. Syst. 35 1609-40) and Shen and Zhang (2012 Comm. Appl. Nonlinear Anal. 19 73-101) for nonlocal dispersal Fisher-KPP equations with time and/or space periodic dependence. The stability result established in this paper implies that the transition waves obtained in many of the above mentioned papers are asymptotically stable for well-fitted perturbation. Up to the author’s knowledge, it is the first time that the stability of transition waves of Fisher-KPP equations with general time and space dependence is studied.
Numerical solution of a spatio-temporal gender-structured model for hantavirus infection in rodents.
Bürger, Raimund; Chowell, Gerardo; Gavilán, Elvis; Mulet, Pep; Villada, Luis M
2018-02-01
In this article we describe the transmission dynamics of hantavirus in rodents using a spatio-temporal susceptible-exposed-infective-recovered (SEIR) compartmental model that distinguishes between male and female subpopulations [L.J.S. Allen, R.K. McCormack and C.B. Jonsson, Bull. Math. Biol. 68 (2006), 511--524]. Both subpopulations are assumed to differ in their movement with respect to local variations in the densities of their own and the opposite gender group. Three alternative models for the movement of the male individuals are examined. In some cases the movement is not only directed by the gradient of a density (as in the standard diffusive case), but also by a non-local convolution of density values as proposed, in another context, in [R.M. Colombo and E. Rossi, Commun. Math. Sci., 13 (2015), 369--400]. An efficient numerical method for the resulting convection-diffusion-reaction system of partial differential equations is proposed. This method involves techniques of weighted essentially non-oscillatory (WENO) reconstructions in combination with implicit-explicit Runge-Kutta (IMEX-RK) methods for time stepping. The numerical results demonstrate significant differences in the spatio-temporal behavior predicted by the different models, which suggest future research directions.
Marwah, Ashok; Marwah, Padma; Lardy, Henry
2005-09-25
17alpha-Methyltestosterone (MT) is used to manipulate the gender of a variety of fish species. A high performance liquid chromatography (HPLC) internal standard method for the determination of 17alpha-methyltestosterone in fish feed using 3beta-methoxy-17beta-hydroxyandrost-5-en-7-one as internal standard (IS) has been developed. The method has been validated for the quantitation of MT in fish feed using 245 nm UV absorbance as the parent wavelength and 255 nm as a qualifier wavelength. The method was validated in the concentration range of 15.0-120 mg/kg of 17alpha-methyltestosterone in fish feed. Method was also found to be suitable for other feeds.
Inhibition of HIF-2.alpha. heterodimerization with HIF1.beta. (ARNT)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bruick, Richard K.; Caldwell, Charles G.; Frantz, Doug E.
2017-09-12
Provided is a method of inhibiting heterodimerization of HIF-2.alpha. to HIF1.beta. (ARNT) comprising binding certain small molecules to the HIF-2.alpha. PAS-B domain cavity but not to HIF1.alpha. and inhibiting HIF-2.alpha. heterodimerization to HIF1.beta. (ARNT) but not inhibiting HIF1.alpha. heterodimerization to HIF1.beta. (ARNT). Those certain small molecules are also referenced synonymously as HIF2-HDI and HIF2.alpha. heterodimerization inhibitors and also simply as certain small molecules.
2007-10-31
equation of ultrafine particles , or (JP-8) fuel vapor, whose dominant radial transfer mechanisms are Brownian motion and turbulent dispersion is given in...Deposition of ultrafine particles at carinal ridges of the upper bronchial airways. Aerosol Science and Technology 38, 991-1000. Comer, J.K...from studies of ultrafine particles . Environmental Health Perspectives 113, 823-839. Ritchie, G., Still, K., Rossi III, J., Bekkedal, M., Bobb, A. and
Malheiro, Ricardo; Casal, Susana; Cunha, Sara C; Baptista, Paula; Pereira, José Alberto
2016-01-01
The olive fly, Bactrocera oleae (Rossi), is a monophagous pest that displays an oviposition preference among cultivars of olive (Olea europaea L.). To clarify the oviposition preference, the olive leaf volatiles of three olive cultivars (Cobrançosa, Madural and Verdeal Transmontana) were assessed by headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC/MS) at six different periods of olive fruit maturation and degrees of infestation. A total of 39 volatiles were identified, mainly esters and alcohols, with a minor percentage of aldehydes, ketones and terpenic compounds, including sesquiterpenes. At sampling dates with higher degrees of infestation, cv. Cobrançosa had, simultaneously, significantly lower infestation degrees and higher volatile amounts than the other two cultivars, with a probable deterrent effect for oviposition. The green leaf volatiles (GLVs) (Z)-3-hexen-1-ol and (Z)-3-hexen-1-ol acetate) were the main compounds identified in all cultivars, together with toluene. The abundance of GLVs decreased significantly throughout maturation, without significant differences among cultivars, while toluene showed a general increase and positive correlation with olive fly infestation levels. The results obtained could broaden our understanding of the roles of various types and amounts of olive volatiles in the environment, especially in olive fly host selection and cultivar preference. Copyright © 2015 Elsevier Ltd. All rights reserved.
FULL SPECTRAL SURVEY OF ACTIVE GALACTIC NUCLEI IN THE ROSSI X-RAY TIMING EXPLORER ARCHIVE
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rivers, Elizabeth; Markowitz, Alex; Rothschild, Richard, E-mail: erivers@ucsd.edu
2013-08-01
We have analyzed spectra for all active galactic nuclei (AGNs) in the Rossi X-ray Timing Explorer archive. We present long-term average values of absorption, Fe line equivalent width (EW), Compton reflection, and photon index, and calculate fluxes and luminosities in the 2-10 keV band for 100 AGN with sufficient brightness and overall observation time to yield high-quality spectral results. We compare these parameters across the different classifications of Seyferts and blazars. Our distributions of photon indices for Seyfert 1s and 2s are consistent with the idea that Seyferts share a common central engine; however, our distributions of Compton reflection humpmore » strengths do not support the classical picture of absorption by a torus and reflection off a Compton-thick disk with type depending only on inclination angle. We conclude that a more complex reflecting geometry such as a combined disk and torus or clumpy torus is likely a more accurate picture of the Compton-thick material. We find that Compton reflection is present in {approx}85% of Seyferts and by comparing Fe line EW's to Compton reflection hump strengths we have found that on average 40% of the Fe line arises in Compton thick material; however, this ratio was not consistent from object to object and did not seem to be dependent on optical classification.« less
SPECTRAL SURVEY OF X-RAY BRIGHT ACTIVE GALACTIC NUCLEI FROM THE ROSSI X-RAY TIMING EXPLORER
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rivers, Elizabeth; Markowitz, Alex; Rothschild, Richard, E-mail: erivers@ucsd.edu
2011-03-15
Using long-term monitoring data from the Rossi X-ray Timing Explorer (RXTE), we have selected 23 active galactic nuclei (AGNs) with sufficient brightness and overall observation time to derive broadband X-ray spectra from 3 to {approx}>100 keV. Our sample includes mainly radio-quiet Seyferts, as well as seven radio-loud sources. Given the longevity of the RXTE mission, the greater part of our data is spread out over more than a decade, providing truly long-term average spectra and eliminating inconsistencies arising from variability. We present long-term average values of absorption, Fe line parameters, Compton reflection strengths, and photon indices, as well as fluxesmore » and luminosities for the hard and very hard energy bands, 2-10 keV and 20-100 keV, respectively. We find tentative evidence for high-energy rollovers in three of our objects. We improve upon previous surveys of the very hard X-ray energy band in terms of accuracy and sensitivity, particularly with respect to confirming and quantifying the Compton reflection component. This survey is meant to provide a baseline for future analysis with respect to the long-term averages for these sources and to cement the legacy of RXTE, and especially its High Energy X-ray Timing Experiment, as a contributor to AGN spectral science.« less
USDA-ARS?s Scientific Manuscript database
A report is given on a new industrial method for the determination of the activity or strength of commercial alpha-amylase at a sugarcane factory or refinery, as well as a recommendation. At the present time, the activities or strengths of commercial alpha-amylases cannot be directly compared becau...
Rapid detection of α-thalassaemia variants using droplet digital PCR.
Lee, T-Y; Lai, M-I; Ramachandran, V; Tan, J A M A; Teh, L-K; Othman, R; Hussein, N H; George, E
2016-08-01
Alpha thalassaemia is a highly prevalent disease globally and is a well-known public health problem in Malaysia. The deletional forms of the mutation are the most common forms found in alpha thalassaemia. The three most common deletional alpha thalassaemia found in this region include --(SEA) deletion, -α(3.7) rightward and -α(4.2) leftward deletions. The prevalence rate of triplication alpha cases such as ααα(anti3.7) and ααα(anti4.2) is not known in Malaysia although it plays a role in exacerbating the clinical phenotypes in beta thalassaemia carriers. Recently, there have been more reported cases of rare alpha thalassaemia mutations due to the advancement of molecular techniques involved in thalassaemia detections. Therefore, it is essential to develop a new method which allows the detection of different alpha thalassaemia mutations including the rare ones simultaneously and accurately. The purpose of this study was to design an assay for the detection of triplications, common and rare deletional alpha thalassaemia using droplet digital PCR (ddPCR). This is a quantitative detection method to measure the changes of copy number which can detect deletions, duplications and triplications of the alpha globin gene simultaneously. In conclusion, ddPCR is an alternative method for rapid detection of alpha thalassaemia variants in Malaysia. © 2016 John Wiley & Sons Ltd.
Measurement of alpha particle energy using windowless electret ion chambers.
Dua, S K; Kotrappa, P; Srivastava, R; Ebadian, M A; Stieff, L R
2002-10-01
Electret ion chambers are inexpensive, lightweight, robust, commercially available, passive, charge-integrating devices for accurate measurement of different ionizing radiations. In an earlier work a chamber of dimensions larger than the range of alpha particles having aluminized Mylar windows of different thickness was used for measurement of alpha radiation. Correlation between electret mid-point voltage, alpha particle energy, and response was developed and it was shown that this chamber could be used for estimating the effective energy of an unknown alpha source. In the present study, the electret ion chamber is used in the windowless mode so that the alpha particles dissipate their entire energy inside the volume, and the alpha particle energy is determined from the first principles. This requires that alpha disintegration rate be accurately known or measured by an alternate method. The measured energies were within 1 to 4% of the true values for different sources (230Th, 237Np, 239Pu, 241Am, and 224Cm). This method finds application in quantitative determination of alpha energy absorbed in thin membrane and, hence, the absorbed dose.
Steiper, Michael E; Wolfe, Nathan D; Karesh, William B; Kilbourn, Annelisa M; Bosi, Edwin J; Ruvolo, Maryellen
2006-07-01
The alpha-globin genes are implicated in human resistance to malaria, a disease caused by Plasmodium parasites. This study is the first to analyze DNA sequences from a novel alpha-globin-type gene in orangutans, a species affected by Plasmodium. Phylogenetic methods show that the gene is a duplication of an alpha-globin gene and is located 5' of alpha-2 globin. The alpha-globin-type gene is notable for having four amino acid replacements relative to the orangutan's alpha-1 and alpha-2 globin genes, with no synonymous differences. Pairwise K(a)/K(s) methods and likelihood ratio tests (LRTs) revealed that the evolutionary history of the alpha-globin-type gene has been marked by either neutral or positive evolution, but not purifying selection. A comparative analysis of the amino acid replacements of the alpha-globin-type gene with human hemoglobinopathies and hemoglobin structure showed that two of the four replaced sites are members of the same molecular bond, one that is crucial to the proper functioning of the hemoglobin molecule. This suggested an adaptive evolutionary change. Functionally, this locus may result in a thalassemia-like phenotype in orangutans, possibly as an adaptation to combat Plasmodium.
Bayesian meta-analysis of Cronbach's coefficient alpha to evaluate informative hypotheses.
Okada, Kensuke
2015-12-01
This paper proposes a new method to evaluate informative hypotheses for meta-analysis of Cronbach's coefficient alpha using a Bayesian approach. The coefficient alpha is one of the most widely used reliability indices. In meta-analyses of reliability, researchers typically form specific informative hypotheses beforehand, such as 'alpha of this test is greater than 0.8' or 'alpha of one form of a test is greater than the others.' The proposed method enables direct evaluation of these informative hypotheses. To this end, a Bayes factor is calculated to evaluate the informative hypothesis against its complement. It allows researchers to summarize the evidence provided by previous studies in favor of their informative hypothesis. The proposed approach can be seen as a natural extension of the Bayesian meta-analysis of coefficient alpha recently proposed in this journal (Brannick and Zhang, 2013). The proposed method is illustrated through two meta-analyses of real data that evaluate different kinds of informative hypotheses on superpopulation: one is that alpha of a particular test is above the criterion value, and the other is that alphas among different test versions have ordered relationships. Informative hypotheses are supported from the data in both cases, suggesting that the proposed approach is promising for application. Copyright © 2015 John Wiley & Sons, Ltd.
Labeled ALPHA4BETA2 ligands and methods therefor
Mukherjee, Jogeshwar; Pichika, Ramaiah; Potkin, Steven; Leslie, Frances; Chattopadhyay, Sankha
2013-02-19
Contemplated compositions and methods are employed to bind in vitro and in vivo to an .alpha.4.beta.2 nicotinic acetylcholine receptor in a highly selective manner. Where such compounds are labeled, compositions and methods employing such compounds can be used for PET and SPECT analysis. Alternatively, and/or additionally contemplated compounds can be used as antagonists, partial agonists or agonists in the treatment of diseases or conditions associated with .alpha.4.beta..beta.2 dysfunction.
Dynamic radioactive particle source
Moore, Murray E; Gauss, Adam Benjamin; Justus, Alan Lawrence
2012-06-26
A method and apparatus for providing a timed, synchronized dynamic alpha or beta particle source for testing the response of continuous air monitors (CAMs) for airborne alpha or beta emitters is provided. The method includes providing a radioactive source; placing the radioactive source inside the detection volume of a CAM; and introducing an alpha or beta-emitting isotope while the CAM is in a normal functioning mode.
Functional and genomic analyses of alpha-solenoid proteins.
Fournier, David; Palidwor, Gareth A; Shcherbinin, Sergey; Szengel, Angelika; Schaefer, Martin H; Perez-Iratxeta, Carol; Andrade-Navarro, Miguel A
2013-01-01
Alpha-solenoids are flexible protein structural domains formed by ensembles of alpha-helical repeats (Armadillo and HEAT repeats among others). While homology can be used to detect many of these repeats, some alpha-solenoids have very little sequence homology to proteins of known structure and we expect that many remain undetected. We previously developed a method for detection of alpha-helical repeats based on a neural network trained on a dataset of protein structures. Here we improved the detection algorithm and updated the training dataset using recently solved structures of alpha-solenoids. Unexpectedly, we identified occurrences of alpha-solenoids in solved protein structures that escaped attention, for example within the core of the catalytic subunit of PI3KC. Our results expand the current set of known alpha-solenoids. Application of our tool to the protein universe allowed us to detect their significant enrichment in proteins interacting with many proteins, confirming that alpha-solenoids are generally involved in protein-protein interactions. We then studied the taxonomic distribution of alpha-solenoids to discuss an evolutionary scenario for the emergence of this type of domain, speculating that alpha-solenoids have emerged in multiple taxa in independent events by convergent evolution. We observe a higher rate of alpha-solenoids in eukaryotic genomes and in some prokaryotic families, such as Cyanobacteria and Planctomycetes, which could be associated to increased cellular complexity. The method is available at http://cbdm.mdc-berlin.de/~ard2/.
Grahn, E; Holm, S E; Ekedahl, C; Roos, K
1983-07-01
The interference between alpha-streptococcal strains obtained from patients with repeated tonsillitis and a collection of group A streptococcal strains were studied. For this purpose three in vitro methods were designed and compared. The results obtained by a simple plating technique suitable for screening purposes were found to correlate well with those using more laborious techniques. In a limited scale some of the alpha- and beta-streptococcal combinations were tested under in vivo conditions using a tissue cage model allowing repeated sampling. In most instances agreement between the results of the in vitro and in vivo methods was registered. Several alpha-strains having inhibitory capacity to the majority of a collection of group A streptococci belonging to different serotypes were found, but also alpha-strains with an inhibitory activity restricted to few group A isolates within a certain serotype. Also beta-streptococcal strains with growth inhibiting activity towards some alpha-strains were found. As the methods were chosen to eliminate many of the unspecific inhibitory factors and the beta-hemolytic test strains showed a pattern of inhibition that varied for each of the reference alpha-strains the activity is most likely attributed to bacteriocin-like substances.
Scaleable catalytic asymmetric Strecker syntheses of unnatural alpha-amino acids.
Zuend, Stephan J; Coughlin, Matthew P; Lalonde, Mathieu P; Jacobsen, Eric N
2009-10-15
Alpha-amino acids are the building blocks of proteins and are widely used as components of medicinally active molecules and chiral catalysts. Efficient chemo-enzymatic methods for the synthesis of enantioenriched alpha-amino acids have been developed, but it is still a challenge to obtain non-natural amino acids. Alkene hydrogenation is broadly useful for the enantioselective catalytic synthesis of many classes of amino acids, but it is not possible to obtain alpha-amino acids bearing aryl or quaternary alkyl alpha-substituents using this method. The Strecker synthesis-the reaction of an imine or imine equivalent with hydrogen cyanide, followed by nitrile hydrolysis-is an especially versatile chemical method for the synthesis of racemic alpha-amino acids. Asymmetric Strecker syntheses using stoichiometric amounts of a chiral reagent have been applied successfully on gram-to-kilogram scales, yielding enantiomerically enriched alpha-amino acids. In principle, Strecker syntheses employing sub-stoichiometric quantities of a chiral reagent could provide a practical alternative to these approaches, but the reported catalytic asymmetric methods have seen limited use on preparative scales (more than a gram). The limited utility of existing catalytic methods may be due to several important factors, including the relatively complex and precious nature of the catalysts and the requisite use of hazardous cyanide sources. Here we report a new catalytic asymmetric method for the syntheses of highly enantiomerically enriched non-natural amino acids using a simple chiral amido-thiourea catalyst to control the key hydrocyanation step. This catalyst is robust, without sensitive functional groups, so it is compatible with aqueous cyanide salts, which are safer and easier to handle than other cyanide sources; this makes the method adaptable to large-scale synthesis. We have used this new method to obtain enantiopure amino acids that are not readily prepared by enzymatic methods or by chemical hydrogenation.
Methods for producing silicon carbide fibers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Garnier, John E.; Griffith, George W.
Methods of producing silicon carbide fibers. The method comprises reacting a continuous carbon fiber material and a silicon-containing gas in a reaction chamber at a temperature ranging from approximately 1500.degree. C. to approximately 2000.degree. C. A partial pressure of oxygen in the reaction chamber is maintained at less than approximately 1.01.times.10.sup.2 Pascal to produce continuous alpha silicon carbide fibers. Continuous alpha silicon carbide fibers and articles formed from the continuous alpha silicon carbide fibers are also disclosed.
VRPD Novel Combinatory Approaches to Repair Visual System After Optic Nerve Damage
2015-05-01
At 4 and 8 weeks after injury, retinas were immunostained with an antibody against beta III tubulin (TUJ1) to estimate RGC survival. The degree of...Optic chiasm presentation of Semaphorin6D in the context of Plexin-A1 and Nr- CAM promotes retinal axon midline crossing. Neuron 74, 676–690. Leaver...for Nr- CAM in the patterning of binocular visual pathways. Neuron 50, 535–547. Williams, S.E., Mann, F., Erskine, L., Sakurai, T., Wei, S., Rossi, D.J
2017-09-01
MDS Myelodysplastic syndrome and acute myeloid leukemia has been reported in patients previously treated with anti-CD20 based RIT for non-hodgkin’s...RR, Rossi A, Jhaveri K, Feldman EJ, Leonard JP. Therapy-related myelodysplastic syndrome and acute myeloid leukemia following initial treatment with... syndrome and acute myelogenous leukemia in patients treated with ibritumomab tiuxetan radioimmunotherapy. J Clin Oncol. 2007 Sep 20;25(27):4285-92. 119
The Effects of Noise on Performance
1989-06-01
Performance" by C. S. Harris in W. D. Ward (Ed.) Proceedings of the International Congress on Noise as a Public Health Problem (EPA 550/9-73-008), 1973, U.S...141a duration tracking for primary task. Suggestion 35 at 1-9s Intervals Secondary task-response ot addivity for secondary 55 time task decrement. 95...In G. Rossi (Ed.) Pro eedings of the Fourth International Congress on Noise as a Public Health Problem, Vol- 2. Milan: Centro Ricerche e Studi
Photon-Enhanced Electron Attachment Processes in Discharge-Opening Switches.
1987-02-01
period from 15 August 1983 through Auget 4 By: M. J. Rossi, H. Helm, and D. C. Lorents MAY 2 699 Prepared for: U.S. ARMY RESEARCH OFFICE P.O. Box 12211...A.. - .. Research Triangle Park, NC 27709 Attention: Dr. R. Gunther and Dr. D. Skatrud Contract No. DAAG29-83-K-01 13 SRI Project PYU-6261 Approved...iDENTIFICATION NUMBER ORGANIZATION (if applicable) J.S. Army Research office [________A -X e3 Ot-03 SC. ADDRESS (City, State. and ZIP Code) 10 SOURCE OF
Microscopic Control of Semiconductor Interface Reactivity.
1986-01-10
Phys. Rev. B 28, and references therein. 4889 (1983). 60 Bisi. C. Calandra, L. Braicovich, I. Abbati, G. Rossi, 1. Lindau, 13A. Hiraki , K. Shuto, S. Kim...under grant No. DMR-8020164 and we gratefully acknowledge the cheerful support of its staff. REFERENCES 1. A. Hiraki , M. A. Nicolet, and J. W. Mayer...Appl. Phys. Lett. 18, 178 (1971); T. Narusawa, S. Komiya, and A. Hiraki , Appl. Phys. Lett. 20, 278 (1972). 2. A. Cros, J. Derrien, and F. Salvan, Surf
Miller, M.
2011-01-01
The article discusses the latest developments in the barite or baryte industry, particularly in the U.S., as of June 2011. It claims that the bulk of barites production in the country comes from four mines in Nevada, including the Big Ledge Mine, the Rossi Mine and the Greystone Mine. It cites that barite is mainly used as a weighting agent in natural gas and oil field drilling muds. Barite is also utilized as filler, extender or weighting agent in such products as paints, plastics and rubber.
Bayesian Meta-Analysis of Cronbach's Coefficient Alpha to Evaluate Informative Hypotheses
ERIC Educational Resources Information Center
Okada, Kensuke
2015-01-01
This paper proposes a new method to evaluate informative hypotheses for meta-analysis of Cronbach's coefficient alpha using a Bayesian approach. The coefficient alpha is one of the most widely used reliability indices. In meta-analyses of reliability, researchers typically form specific informative hypotheses beforehand, such as "alpha of…
Xanthanolides and xanthane epoxide derivatives from Xanthium strumarium.
Mahmoud, A A
1998-12-01
From the aerial parts of Xanthium strumarium, three new xanthanolide and xanthane-type sesquiterpenoids, 11alpha,13-dihydroxanthatin, 4beta,5beta-epoxyxanthatin-1alpha,4alpha-endoperoxide, and 1beta,4beta,4alpha,5alpha-diepoxyxanth-11(13)-en-12-oic acid have been isolated, together with seven known compounds. The structures were determined by spectroscopic methods, particularly high resolution 1D, 2D NMR spectroscopy and NOE experiments.
Review of chemical separation techniques applicable to alpha spectrometric measurements
NASA Astrophysics Data System (ADS)
de Regge, P.; Boden, R.
1984-06-01
Prior to alpha-spectrometric measurements several chemical manipulations are usually required to obtain alpha-radiating sources with the desired radiochemical and chemical purity. These include sampling, dissolution or leaching of the elements of interest, conditioning of the solution, chemical separation and preparation of the alpha-emitting source. The choice of a particular method is dependent on different criteria but always involves aspects of the selectivity or the quantitative nature of the separations. The availability of suitable tracers or spikes and modern high resolution instruments resulted in the wide-spread application of isotopic dilution techniques to the problems associated with quantitative chemical separations. This enhanced the development of highly elective methods and reagents which led to important simplifications in the separation schemes. The chemical separation methods commonly used in connection with alpha-spectrometric measurements involve precipitation with selected scavenger elements, solvent extraction, ion exchange and electrodeposition techniques or any combination of them. Depending on the purpose of the final measurement and the type of sample available the chemical separation methods have to be adapted to the particular needs of environment monitoring, nuclear chemistry and metrology, safeguards and safety, waste management and requirements in the nuclear fuel cycle. Against the background of separation methods available in the literature the present paper highlights the current developments and trends in the chemical techniques applicable to alpha spectrometry.
NASA Technical Reports Server (NTRS)
Shaposhnikov, Nickolai; Titarchuk, Lev
2006-01-01
We present timing and spectral analysis of approx. 2.2 Ms of Rossi X-ray Time Explorer (RXTE) archival data from Cyg X-1. Using the generic Comptonization model we reveal that the spectrum of Cyg X-1 consists of three components: a thermal seed photon spectrum, a Comptonized part of the seed photon spectrum and the iron line. We find a strong correlation between 0.1-20 Hz frequencies of quasiperiodic oscillations (QPOs) and the spectral power-law index. Presence of two spectral phases (states) are clearly seen in the data when the spectral indices saturate at low and high values of QPO frequencies. This saturation effect was discovered earlier in a number of black hole candidate (BHC) sources and now we strongly confirm this phenomenon in Cyg X-1. In the soft state this index- QPO frequency correlation shows a saturation of the photon index Gamma approx. 2.1 at high values of the low frequency upsilon(sub L). The saturation level of Gamma approx. 2.1 is the lowest value found yet in BHCs. The bolometric luminosity does not show clear correlation with the index. We also show that Fe K(sub alpha) emission line strength (equivalent width, EW) correlates with the QPO frequency. EW increases from 200 eV in the low/hard state to 1.5 keV in the high/soft state. The revealed observational correlations allow us to propose a scenario for the spectral transition and iron line formation which occur in BHC sources. We also present the spectral state (the power-law index) evolution for eight years of Cyg X-1 observations by RXTE.
Methods for constraining fine structure constant evolution with OH microwave transitions.
Darling, Jeremy
2003-07-04
We investigate the constraints that OH microwave transitions in megamasers and molecular absorbers at cosmological distances may place on the evolution of the fine structure constant alpha=e(2)/ variant Planck's over 2pi c. The centimeter OH transitions are a combination of hyperfine splitting and lambda doubling that can constrain the cosmic evolution of alpha from a single species, avoiding systematic errors in alpha measurements from multiple species which may have relative velocity offsets. The most promising method compares the 18 and 6 cm OH lines, includes a calibration of systematic errors, and offers multiple determinations of alpha in a single object. Comparisons of OH lines to the HI 21 cm line and CO rotational transitions also show promise.
Functional and Genomic Analyses of Alpha-Solenoid Proteins
Fournier, David; Palidwor, Gareth A.; Shcherbinin, Sergey; Szengel, Angelika; Schaefer, Martin H.; Perez-Iratxeta, Carol; Andrade-Navarro, Miguel A.
2013-01-01
Alpha-solenoids are flexible protein structural domains formed by ensembles of alpha-helical repeats (Armadillo and HEAT repeats among others). While homology can be used to detect many of these repeats, some alpha-solenoids have very little sequence homology to proteins of known structure and we expect that many remain undetected. We previously developed a method for detection of alpha-helical repeats based on a neural network trained on a dataset of protein structures. Here we improved the detection algorithm and updated the training dataset using recently solved structures of alpha-solenoids. Unexpectedly, we identified occurrences of alpha-solenoids in solved protein structures that escaped attention, for example within the core of the catalytic subunit of PI3KC. Our results expand the current set of known alpha-solenoids. Application of our tool to the protein universe allowed us to detect their significant enrichment in proteins interacting with many proteins, confirming that alpha-solenoids are generally involved in protein-protein interactions. We then studied the taxonomic distribution of alpha-solenoids to discuss an evolutionary scenario for the emergence of this type of domain, speculating that alpha-solenoids have emerged in multiple taxa in independent events by convergent evolution. We observe a higher rate of alpha-solenoids in eukaryotic genomes and in some prokaryotic families, such as Cyanobacteria and Planctomycetes, which could be associated to increased cellular complexity. The method is available at http://cbdm.mdc-berlin.de/~ard2/. PMID:24278209
Imaging alpha particle detector
Anderson, David F.
1985-01-01
A method and apparatus for detecting and imaging alpha particles sources is described. A conducting coated high voltage electrode (1) and a tungsten wire grid (2) constitute a diode configuration discharge generator for electrons dislodged from atoms or molecules located in between these electrodes when struck by alpha particles from a source (3) to be quantitatively or qualitatively analyzed. A thin polyester film window (4) allows the alpha particles to pass into the gas enclosure and the combination of the glass electrode, grid and window is light transparent such that the details of the source which is imaged with high resolution and sensitivity by the sparks produced can be observed visually as well. The source can be viewed directly, electronically counted or integrated over time using photographic methods. A significant increase in sensitivity over other alpha particle detectors is observed, and the device has very low sensitivity to gamma or beta emissions which might otherwise appear as noise on the alpha particle signal.
Imaging alpha particle detector
Anderson, D.F.
1980-10-29
A method and apparatus for detecting and imaging alpha particles sources is described. A dielectric coated high voltage electrode and a tungsten wire grid constitute a diode configuration discharge generator for electrons dislodged from atoms or molecules located in between these electrodes when struck by alpha particles from a source to be quantitatively or qualitatively analyzed. A thin polyester film window allows the alpha particles to pass into the gas enclosure and the combination of the glass electrode, grid and window is light transparent such that the details of the source which is imaged with high resolution and sensitivity by the sparks produced can be observed visually as well. The source can be viewed directly, electronically counted or integrated over time using photographic methods. A significant increase in sensitivity over other alpha particle detectors is observed, and the device has very low sensitivity to gamma or beta emissions which might otherwise appear as noise on the alpha particle signal.
Misdaq, M A; Aitnouh, F; Khajmi, H; Ezzahery, H; Berrazzouk, S
2001-08-01
A Monte Carlo computer code for determining detection efficiencies of the CR-39 and LR-115 II solid-state nuclear track detectors (SSNTD) for alpha-particles emitted by the uranium and thorium series inside different natural material samples was developed. The influence of the alpha-particle initial energy on the SSNTD detection efficiencies was investigated. Radon (222Rn) and thoron (220Rn) alpha-activities per unit volume were evaluated inside and outside the natural material samples by exploiting data obtained for the detection efficiencies of the SSNTD utilized for the emitted alpha-particles, and measuring the resulting track densities. Results obtained were compared to those obtained by other methods. Radon emanation coefficients have been determined for some of the considered material samples.
Konzen, Kevin; Brey, Richard
2012-05-01
²²²Rn (radon) and ²²⁰Rn (thoron) progeny are known to interfere with determining the presence of long-lived transuranic radionuclides, such as plutonium and americium, and require from several hours up to several days for conclusive results. Methods are proposed that should expedite the analysis of air samples for determining the amount of transuranic radionuclides present using low-resolution alpha spectroscopy systems available from typical alpha continuous air monitors (CAMs) with multi-channel analyzer (MCA) capabilities. An alpha spectra simulation program was developed in Microsoft Excel visual basic that employed the use of Monte Carlo numerical methods and serial-decay differential equations that resembled actual spectra. Transuranic radionuclides were able to be quantified with statistical certainty by applying peak fitting equations using the method of least squares. Initial favorable results were achieved when samples containing radon progeny were decayed 15 to 30 min, and samples containing both radon and thoron progeny were decayed at least 60 min. The effort indicates that timely decisions can be made when determining transuranic activity using available alpha CAMs with alpha spectroscopy capabilities for counting retrospective air samples if accompanied by analyses that consider the characteristics of serial decay.
Dahl, Jeffrey H; van Breemen, Richard B
2010-09-15
A rapid liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay was developed for the measurement of urinary 8-iso-prostaglandin F(2alpha) (8-iso-PGF(2alpha)), a biomarker of lipid peroxidation. Because urine contains numerous F(2) prostaglandin isomers, each with identical mass and similar mass spectrometric fragmentation patterns, chromatographic separation of 8-iso-PGF(2alpha) from its isomers is necessary for its quantitative analysis using MS/MS. We were able to achieve this separation using an isocratic LC method with a run time of less than 9min, which is at least threefold faster than previous methods, while maintaining sensitivity, accuracy, precision, and reliability. The limits of detection and quantitation were 53 and 178pg/ml urine, respectively. We compared our method with a commercially available affinity purification and enzyme immunoassay kit and found both assays to be in agreement. Despite the high sensitivity of the enzyme immunoassay method, it is more expensive and has a narrower dynamic range than LC-MS/MS. Our method was optimized for rapid measurement of 8-iso-PGF(2alpha) in urine, and it is ideally suited for clinical sample analysis. 2010 Elsevier Inc. All rights reserved.
Malheiro, R; Casal, S; Pinheiro, L; Baptista, P; Pereira, J A
2018-02-21
The olive fly, Bactrocera oleae (Rossi) (Diptera: Tephritidae), is a key-pest in the main olives producing areas worldwide, and displays distinct preference to different olive cultivars. The present work intended to study oviposition preference towards three Portuguese cultivars (Cobrançosa, Madural, and Verdeal Transmontana) at different maturation indexes. Multiple oviposition bioassays (multiple-choice and no-choice) were conducted to assess cultivar preference. No-choice bioassays were conducted to assess the influence of different maturation indexes (MI 2; MI 3, and MI 4) in single cultivars. The longevity of olive fly adults according to the cultivar in which its larvae developed was also evaluated through survival assays. Cultivar and maturation are crucial aspects in olive fly preference. Field and laboratory assays revealed a preference towards cv. Verdeal Transmontana olives and a lower susceptibility to cv. Cobrançosa olives. A higher preference was observed for olives at MI 2 and MI 3. The slower maturation process in cv. Verdeal Transmontana (still green while the other cultivars are reddish or at black stage) seems to have an attractive effect on olive fly females, thus increasing its infestation levels. Olive fly adults from both sexes live longer if emerged from pupae developed from cv. Verdeal Transmontana fruits and live less if emerged from cv. Cobrançosa. Therefore, olive cultivar and maturation process are crucial aspects in olive fly preference, also influencing the longevity of adults.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Suhara, Tadahiro; Kanada-En'yo, Yoshiko
Structures of excited states in {sup 14}C are investigated with a method of {beta}-{gamma} constraint antisymmetrized molecular dynamics in combination with the generator coordinate method. Various excited states with the developed 3{alpha}-cluster core structures are suggested in positive- and negative-parity states. In the positive-parity states, triaxial deformed and linear-chain structures are found to construct excited bands. Interestingly, {sup 10}Be+{alpha} correlation is found in the cluster states above the {sup 10}Be+{alpha} threshold energy.
THE SPIN OF THE BLACK HOLE 4U 1543-47
DOE Office of Scientific and Technical Information (OSTI.GOV)
Morningstar, Warren R.; Miller, Jon M., E-mail: wmorning@umich.edu, E-mail: jonmm@umich.edu
2014-10-01
We present a new analysis of Rossi X-Ray Timing Explorer observations of the 2002 outburst of the transient X-ray nova 4U 1543-47. We focus on observations in the high/soft state, and attempt to measure the ''spin'' of the black hole by simultaneously fitting the thermal disk continuum and by modeling the broadened iron k-shell emission lines and additional blurred reflection features. Previous works have found that use of these methods individually returns contradictory values for the dimensionless spin parameter a {sub *} = cJ/GM {sup 2}. We find that when used in conjunction with each other, a moderate spin ismore » obtained (a{sub ∗}=0.43{sub −0.31}{sup +0.22}) that is actually consistent with both other values within errors. We discuss limitations of our analysis, systematic uncertainties, and implications of this measurement, and compare our result to those previously claimed for 4U 1543-47.« less
Vázquez-Iglesias, Lorena; Estefanell-Ucha, Borja; Barcia-Castro, Leticia; Páez de la Cadena, María; Álvarez-Chaver, Paula; Ayude-Vázquez, Daniel; Rodríguez-Berrocal, Francisco Javier
2017-01-01
Clostridium septicum produces a number of diseases in human and farm animals which, in most of the cases, are fatal without clinical intervention. Alpha toxin is an important agent and the unique lethal virulent factor produced by Clostridium septicum. This toxin is haemolytic, highly lethal and necrotizing activities but is being used as an antigen to develop animal vaccines. The aim of this study was to isolate the alpha toxin of Clostridium septicum and produce highly specific antibodies against it. In this work, we have developed a simple and efficient method for alpha toxin purification, based on electroelution that can be used as a time-saving method for purifying proteins. This technique avoids contamination by other proteins that could appear during other protein purification techniques such chromatography. The highly purified toxin was used to produce polyclonal antibodies. The specificity of the antibodies was tested by western blot and these antibodies can be applied to the quantitative determination of alpha toxin by slot blot.
Estefanell-Ucha, Borja; Barcia-Castro, Leticia; Páez de la Cadena, María; Álvarez-Chaver, Paula; Ayude-Vázquez, Daniel; Rodríguez-Berrocal, Francisco Javier
2017-01-01
Clostridium septicum produces a number of diseases in human and farm animals which, in most of the cases, are fatal without clinical intervention. Alpha toxin is an important agent and the unique lethal virulent factor produced by Clostridium septicum. This toxin is haemolytic, highly lethal and necrotizing activities but is being used as an antigen to develop animal vaccines. The aim of this study was to isolate the alpha toxin of Clostridium septicum and produce highly specific antibodies against it. In this work, we have developed a simple and efficient method for alpha toxin purification, based on electroelution that can be used as a time-saving method for purifying proteins. This technique avoids contamination by other proteins that could appear during other protein purification techniques such chromatography. The highly purified toxin was used to produce polyclonal antibodies. The specificity of the antibodies was tested by western blot and these antibodies can be applied to the quantitative determination of alpha toxin by slot blot. PMID:28652930
Sakamoto, Masaki; Uchihara, Toshiki; Nakamura, Ayako; Mizutani, Toshio; Mizusawa, Hidehiro
2005-10-01
Alpha-synuclein (alphaS) and ubiquitin (Ub) are shared constituents of glial cytoplasmic inclusions (GCIs) and Lewy bodies (LBs), both composed of fibrillary structures. Staining profiles of GCIs were investigated with triple immunofluorescence involving immunostaining for alphaS and Ub, both amplified with catalyzed reporter deposition, and a fluorochrome, thiazin red (TR) that has an affinity to fibrillary structures. After observation for the triple-fluorescent images, the sections were subsequently stained with the Gallyas-Braak method. Sections of putamen, cerebellar white matter and motor cortex from patients suffering from multiple system atrophy (MSA) with varying duration of the disease (4-15 years) were quantified for these staining profiles of Gallyas-positive GCIs. Although most of GCIs were positive for Ub and variably positive for alphaS, they were consistently negative for TR. The result was opposite in LBs in Lewy body disease with variable affinity to TR, suggesting that the construction of GCIs is different from that of LBs. These four staining features (alphaS, Ub, TR and Gallyas) alone failed to exhibit apparent correlation with disease duration, lesion site or severity of degeneration as reported previously. The fraction of alphaS-negative and Ub-positive GCIs, however, linearly increased along the disease progression, while that of alphaS-positive and Ub-negative GCIs decreased in contrast. This reciprocal change suggests that alphaS immunoreactivity in GCIs is being replaced by Ub immunoreactivity during the disease progression, which resulted in the ultimate predominance of alphaS-negative and Ub-positive GCIs in the most advanced case. Interestingly, this predominance of alphaS-negative and Ub-positive GCIs was a feature of motor cortex, where degeneration usually remains mild in spite of robust appearance of Gallyas-positive GCIs. Another fraction, alphaS-positive and Ub-positive GCIs were frequent in cerebellar white matter, suggesting that GCI evolution is heterogeneous and dependent also on area examined. Progressive accumulation of Ub with concomitant disappearance of alphaS epitope and their colocalization, partly shared with LBs, may represent a process of GCI formation, possibly linked to an aspect of degeneration in MSA.
Method for using a yeast alpha-amylase promoter
Gao, Johnway; Skeen, Rodney S.; Hooker, Brian S.; Anderson, Daniel B.
2003-04-22
The present invention provides the promoter clone discovery of an alpha-amylase gene of a starch utilizing yeast strain Schwanniomyces castellii. The isolated alpha-amylase promoter is an inducible promoter, which can regulate strong gene expression in starch culture medium.
Kotkar, Shriram P; Chavan, Vilas B; Sudalai, Arumugam
2007-03-15
A novel and highly enantioselective method for the synthesis of gamma-amino-alpha,beta-unsaturated esters via tandem alpha-amination-Horner-Wadsworth-Emmons (HWE) olefination of aldehydes is described. The one-pot assembly has been demonstrated for the construction of functionalized chiral 2-pyrrolidones, subunits present in several alkaloids. [structure: see text
Principles of gross alpha and beta radioactivity detection in water.
Semkow, T M; Parekh, P P
2001-11-01
A simultaneous detection of gross alpha and beta radioactivity was studied using gas proportional counting. This measurement is a part of a method mandated by US Environmental Protection Agency to screen for alpha and beta radioactivity in drinking water. Responses of a gas proportional detector to alpha and beta particles from several radionuclides were determined in drop and electroplated geometries. It is shown that, while the alpha radioactivity can be measured accurately in the presence of beta radioactivity, the opposite is not typically true due to alpha-to-beta crosstalk. The crosstalk, originating from the emission of conversion and Auger electrons as well as x rays, is shown to be dependent primarily on the particular alpha-decay scheme while the dependence on alpha energy is small but negligible. It was measured at 28-35% for 241Am, 22-24% for 230Th, and 4.9-6.5% for 239Pu. For 210Po, the crosstalk of 1.2-1.6% was observed mostly due to energy retardation. A method of reducing the crosstalk to a <3% level is proposed by absorbing the atomic electrons in a 6.2 mg cm(-2) Al absorber, at the same time decreasing the beta efficiency by 16-31%.
[Building immune microsphere against tumor necrosis factor-alpha (TNF-alpha)].
Wang, Qin; Wu, Xiongfei; Wang, Junxia; Liu, Hong; Li, Lian; Jin, Xiyu
2005-12-01
We have constructed the immune microsphere against tumor necrosis factor-alpha (TNF-alpha) prospectively, hoping to establish the experiment groundwork in more researches which could be used in specific elimination of the TNF-alpha by blood purification method for the future. The recombinant human tumor necrosis factor-alpha monoclonal antibody (rHTNF-alpha McAb) was wrapped on the polystyrene microsphere (PSM) carrier connecting poly-L-lysine (PLL) beforehand. They were earmarked by the fluorescein isothiocyanate (FITC) respectively. The packing conditions were examined using the inversted and fluorescence microscopes and the spectrophotometer. The results showed that the best conditions for wrapping were 20 degrees C, pH9.5 and 60 minutes. The PLL content was not changed in the washing fluid after coating, which indicated the wrapping was quite firm. At the same temperature and same coating time, the rHTNF-alpha McAb coated on the PLL was obviously substantial when the concentration of glutaraldehyde solution was 0.2%. The findings demonstrated that the built immune microsphers can be used as a novel adsorption material. This method is simple and economic, and it offers a new approach to the related studies.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Smales, A.A.; Airey, L.; Woodward, J.
1950-06-01
Consideration has been given to the problem of separating and estimating uranium, polonium, and other alpha emitters (in order to provide analytical methods for their routine determination in conformily with the draft agreement on the Harwell effluent). Uranium may be ether extracted from solutions of ammonium nitrate as salting out agent at pHl with an efficiency of 98 to 99%. The deposition of polonium on silver foil is a specific method for this element and under prescribed conditions similar extraction efficiencies may be obtained. An adequate separation from all other alpha emitters'' is obtained and methods for the estimation ofmore » these are discussed. A comprehensive scheme involving a preliminary activity concentration step has been elaborated. Uranium, polonium, and the majority of the other alpha emitters'' are precipitated as their tannin complexes at pH8 using calcium hydroxide, the calcium-tannin complex acting as a carrier. That part of the activity remaining in solution is determined as in the total activity method, previously described. From the solution of the precipitate, polonium is first separated by electrodeposition, and then uranium by ether extraction in the presence of ammonium nitrate. The majority of the other alpha emitters'' still in the aqueous ammonium nitrate solution are collected on a second calcium-tannin precipitate, while the small part remaining in solution after this operation is obtained by direct evaporation. (auth)« less
NASA Technical Reports Server (NTRS)
Buehler, Martin G. (Inventor); Nixon, Robert H. (Inventor); Soli, George A. (Inventor); Blaes, Brent R. (Inventor)
1995-01-01
A method for predicting the SEU susceptibility of a standard-cell D-latch using an alpha-particle sensitive SRAM, SPICE critical charge simulation results, and alpha-particle interaction physics. A technique utilizing test structures to quickly and inexpensively characterize the SEU sensitivity of standard cell latches intended for use in a space environment. This bench-level approach utilizes alpha particles to induce upsets in a low LET sensitive 4-k bit test SRAM. This SRAM consists of cells that employ an offset voltage to adjust their upset sensitivity and an enlarged sensitive drain junction to enhance the cell's upset rate.
Toward unbiased determination of the redshift evolution of Lyman-alpha forest clouds
NASA Technical Reports Server (NTRS)
Lu, Limin; Zuo, Lin
1994-01-01
The possibility of using D(sub A), the mean depression of a quasar spectrum due to Ly-alpha forest absorption, to study the number density evolution of the Ly-alpha forest clouds is examined in some detail. Current D(sub A) measurements are made against a continuum that is a power-law extrapolation from the continuum longward of Ly-alpha emission. Compared to the line-counting approach, the D(sub A)-method has the advantage that the D(sub A) measurements are not affected by line-blending effects. However, we find using low-redshift quasar spectra obtained with the Hubble Space Telescope (HST), where the true continuum in the Ly-alpha forest can be estimated fairly reliably because of the much lower density of the Ly-alpha forest lines, that the extrapolated continuum often deviates systematically from the true continuum in the forest region. Such systematic continuum errors introduce large errors in the D(sub A) measurements. The current D(sub A) measurements may also be significantly biased by the possible presence of the Gunn-Peterson absorption. We propose a modification to the existing D(sub A)-method, namely, to measure D(sub A) against a locally established continuum in the Ly-alpha forest. Under conditions that the quasar spectrum has good resolution and S/N to allow for a reliable estimate of the local continuum in the Ly-alpha forest, the modified D(sub A) measurements should be largely free of the systematic uncertainties suffered by the existing D(sub A) measurements. We also introduce a formalism based on the work of Zuo (1993) to simplify the application of the D(sub A)-method(s) to real data. We discuss the merits and limitations of the modified D(sub A)-method, and conclude that it is a useful alternative. Our findings that the extrapolated continuum from longward of Ly-alpha emission often deviates systematically from the true continuum in the Ly-alpha forest present a major problem in the study of the Gunn-Peterson absorption.
Method of making nanocrystalline alpha alumina
Siegel, Richard W.; Hahn, Horst; Eastman, Jeffrey A.
1992-01-01
Method of making selected phases of nanocrystalline ceramic materials. Various methods of controlling the production of nanocrystalline alpha alumina and titanium oxygen phases are described. Control of the gas atmosphere and use of particular oxidation treatments give rise to the ability to control the particular phases provided in the aluminum/oxygen and titanium/oxygen system.
NASA Astrophysics Data System (ADS)
Yuliasmi, S.; Pardede, T. R.; Nerdy; Syahputra, H.
2017-03-01
Oil palm midrib is one of the waste generated by palm plants containing 34.89% cellulose. Cellulose has the potential to produce microcrystalline cellulose can be used as an excipient in tablet formulations by direct compression. Microcrystalline cellulose is the result of a controlled hydrolysis of alpha cellulose, so the alpha cellulose extraction process of oil palm midrib greatly affect the quality of the resulting microcrystalline cellulose. The purpose of this study was to compare the microcrystalline cellulose produced from alpha cellulose extracted from oil palm midrib by two different methods. Fisrt delignization method uses sodium hydroxide. Second method uses a mixture of nitric acid and sodium nitrite, and continued with sodium hydroxide and sodium sulfite. Microcrystalline cellulose obtained by both method was characterized separately, including organoleptic test, color reagents test, dissolution test, pH test and determination of functional groups by FTIR. The results was compared with microcrystalline cellulose which has been available on the market. The characterization results showed that microcrystalline cellulose obtained by first method has the most similar characteristics to the microcrystalline cellulose available in the market.
Orr, Christopher Henry; Luff, Craig Janson; Dockray, Thomas; Macarthur, Duncan Whittemore
2002-01-01
The apparatus and method provide techniques for effectively implementing alpha and/or beta and/or gamma monitoring of items or locations as desired. Indirect alpha monitoring by detecting ions generated by alpha emissions, in conjunction with beta and/or gamma monitoring is provided. The invention additionally provides for screening of items prior to alpha monitoring using beta and/or gamma monitoring, so as to ensure that the alpha monitoring apparatus is not contaminated by proceeding direct to alpha monitoring of a heavily contaminated item or location. The invention provides additional versatility in the emission forms which can be monitored, whilst maintaining accuracy and avoiding inadvertent contamination.
Vilaivan, Tirayut; Bhanthumnavin, Worawan
2010-02-11
Organocatalytic asymmetric alpha-oxidation and amination reactions of carbonyl compounds are highly useful synthetic methodologies, especially in generating chiral building blocks that previously have not been easily accessible by traditional methods. The concept is relatively new and therefore the list of new catalysts, oxidizing and aminating reagents, as well as new substrates, are expanding at an amazing rate. The scope of this review includes new reactions and catalysts, mechanistic aspects and synthetic applications of alpha-oxidation, hydroxylation, aminoxylation, amination, hydrazination, hydroxyamination and related alpha-heteroatom functionalization of aldehydes, ketones and related active methylene compounds published during 2005-2009.
Shankar, Manoharan; Priyadharshini, Ramachandran; Gunasekaran, Paramasamy
2009-08-01
An image analysis-based method for high throughput screening of an alpha-amylase mutant library using chromogenic assays was developed. Assays were performed in microplates and high resolution images of the assay plates were read using the Virtual Microplate Reader (VMR) script to quantify the concentration of the chromogen. This method is fast and sensitive in quantifying 0.025-0.3 mg starch/ml as well as 0.05-0.75 mg glucose/ml. It was also an effective screening method for improved alpha-amylase activity with a coefficient of variance of 18%.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Breuker, M.S.; Braun, J.E.
This paper presents a detailed evaluation of the performance of a statistical, rule-based fault detection and diagnostic (FDD) technique presented by Rossi and Braun (1997). Steady-state and transient tests were performed on a simple rooftop air conditioner over a range of conditions and fault levels. The steady-state data without faults were used to train models that predict outputs for normal operation. The transient data with faults were used to evaluate FDD performance. The effect of a number of design variables on FDD sensitivity for different faults was evaluated and two prototype systems were specified for more complete evaluation. Good performancemore » was achieved in detecting and diagnosing five faults using only six temperatures (2 input and 4 output) and linear models. The performance improved by about a factor of two when ten measurements (three input and seven output) and higher order models were used. This approach for evaluating and optimizing the performance of the statistical, rule-based FDD technique could be used as a design and evaluation tool when applying this FDD method to other packaged air-conditioning systems. Furthermore, the approach could also be modified to evaluate the performance of other FDD methods.« less
A comparison of lidar inversion methods for cirrus applications
NASA Technical Reports Server (NTRS)
Elouragini, Salem; Flamant, Pierre H.
1992-01-01
Several methods for inverting the lidar equation are suggested as means to derive the cirrus optical properties (beta backscatter, alpha extinction coefficients, and delta optical depth) at one wavelength. The lidar equation can be inverted in a linear or logarithmic form; either solution assumes a linear relationship: beta = kappa(alpha), where kappa is the lidar ratio. A number of problems prevent us from calculating alpha (or beta) with a good accuracy. Some of these are as follows: (1) the multiple scattering effect (most authors neglect it); (2) an absolute calibration of the lidar system (difficult and sometimes not possible); (3) lack of accuracy on the lidar ratio k (taken as constant, but in fact it varies with range and cloud species); and (4) the determination of boundary condition for logarithmic solution which depends on signal to noise ration (SNR) at cloud top. An inversion in a linear form needs an absolute calibration of the system. In practice one uses molecular backscattering below the cloud to calibrate the system. This method is not permanent because the lower atmosphere turbidity is variable. For a logarithmic solution, a reference extinction coefficient (alpha(sub f)) at cloud top is required. Several methods to determine alpha(sub f) were suggested. We tested these methods at low SNR. This led us to propose two new methods referenced as S1 and S2.
NASA Astrophysics Data System (ADS)
Barret, D.; Olive, J.-F.; Miller, M. Coleman
2005-11-01
Using all available archival data from the Rossi X-ray Timing Explorer (RXTE), we follow the frequency of the kilo-Hz QPOs in three low luminosity neutron star low mass X-ray binaries; namely 4U 1636-536, 4U 1608-522, and 4U 1735-44. Following earlier work by Barret et al. (2005a,b), we focus our analysis on the lower kilo-Hz QPO, for which we study the dependency of its quality factor (Q=\
Commission 20: Position and Motion of Minor Planets, Comets and Satellites
NASA Astrophysics Data System (ADS)
Valsecchi, Giovanni B.; Fernandez, Julio; Bowell, Edward L. G.; Arlot, Jean-Eudes; Bowell, Edward L. G.; Chernetenko, Yulia A.; Chesley, Steven R.; Lazzaro, Daniela; Lemaitre, Anne; Marsden, Brian G.; Muinonen, Karri; Rickman, Hans; Tholen, David J.; Yoshikawa, Makoto
2007-12-01
A total of 16 among the new IAU members have asked to join Commission 20; they are: Jerome Berthier, Nicholas J. Cooper, Marco Delbò, Romina P. Di Sisto, Michael W. Evans, Tetsuharu Fuse, Ludmila Hudkova, Yurij N. Krugly, Elena N. Polyakhova, Zhanna Pozhalova, Alessandro Rossi, Qi Rui, Jonathan D. Shanklin, Slawomira E. Szutowicz, Gino Tuccari and Hong-Suh Yim. Moreover, two requests to join the Commission have been received by astronomers that are already IAU members: Peter De Cat and Ricardo A. Gil-Hutton.
1985-06-01
in Appendix G. The symbols used in Appendix G are the same as those used in the geologic maps by Rossi and Semenza (1965a). Figures 11 and 12 in...the 1963 slide. Their interpretations are presented as Figures 15 through 22 ’ ’ ■ M .i i . 20. The symbols used for the units on these...Weber, E. 1964. Die Katastrophe von Vaiont in Oberitalien, Wasser -und Energiewirtschaft. Vol. 56, No. 2/3, pp. 61-69. Weiss, V. E. H. 1964. Vajont
Consolidated RXTE Observing Grants on Observation of Neutron Stars and Black Holes in Binaries
NASA Technical Reports Server (NTRS)
Prince, Thomas A.; Vaughan, Brian A.
1998-01-01
This final report is a study of neutron stars and black holes in binaries. The activities focused on observation made with the Rossi X-ray Timing Explorer. The following areas were covered: long term observations of accreting binary pulsars with the All-Sky Monitor (ASM); observations of Centaurus X-3 with the Proportional Counter Array (PCA) and the High-Energy X-ray Timing Experiment (HEXTE); observations of accreting pulsars with the PCA and HEXTE; studies of quasi-periodic oscillations (QPO); and investigations of accreting black-hole candidates.
Five-Body Cluster Structure of the Double-{Lambda} Hypernucleus {sub {Lambda}{Lambda}}{sup 11}Be
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hiyama, E.; Kamimura, M.; Yamamoto, Y.
2010-05-28
Energy levels of the double {Lambda} hypernucleus, {sub {Lambda}{Lambda}}{sup 11}Be are calculated within the framework of a {alpha}{alpha}n{Lambda}{Lambda} five-body model. Interactions between constituent particles are determined so as to reproduce reasonably the observed low-energy properties of the {alpha}{alpha}, {alpha}{alpha}n nuclei and the existing data for {Lambda}-binding energies of the {alpha}{Lambda}, {alpha}{alpha}{Lambda}, {alpha}n{Lambda}, and {alpha}{alpha}n{Lambda} systems. An effective {Lambda}{Lambda} interaction is constructed so as to reproduce, within the {alpha}{Lambda}{Lambda} three-body model, the B{sub {Lambda}{Lambda}}of {sub {Lambda}{Lambda}}{sup 6}He, which was extracted from the emulsion experiment, the NAGARA event. With no adjustable parameters for the {alpha}{alpha}n{Lambda}{Lambda} system, B{sub {Lambda}{Lambda}}of the ground and boundmore » excited states of {sub {Lambda}{Lambda}}{sup 11}Be are calculated with the Gaussian expansion method. The Hida event, recently observed at KEK-E373 experiment, is interpreted as an observation of the ground state of the {sub {Lambda}{Lambda}}{sup 11}Be.« less
Development of a method which discriminates between endogenous and exogenous beta-boldenone.
Blokland, M H; van Rossum, H J; Sterk, S S; van Ginkel, L A; Stephany, R W
2007-03-14
One potential explanation for the presence of beta-boldenone in calf urine is contamination of the sample with feces containing beta-boldenone. It has been demonstrated that after oral and intramuscular administration of beta-boldenone esters, several metabolites are formed and excreted in urine. One of the (minor) metabolites is 6beta-hydroxy-17alpha-boldenone. This paper describes an analytical method that can discriminate between unconjugated boldenone, its glucuronide- and sulphate-conjugates, 6beta-hydroxy-17alpha/beta-boldenone and coprostanol, a marker for fecal contamination. The method was applied to all samples suspected to contain boldenone within the Dutch National Residue Control Plan. Approximately 10,000 samples of urine were screened (LC-MS) in 2004-2005 by VWA-East, one of the official Dutch control laboratories, from which 261 samples were suspected to contain boldenone. These samples were all analyzed for their conjugation state, 6beta-hydroxy-17alpha/beta-boldenone and for the presence of coprostanol. Alfa-boldenone, the major metabolite in bovine urine after boldenone-ester administration, was found in a large number of these samples. The presence of alpha-boldenone was proven also to be a result of fecal contamination. None of the samples tested contained residues of the metabolite 6beta-hydroxy-17alpha/beta-boldenone. Not finding this metabolite indicates that the origin of alpha-boldenone-conjugates is endogenous. The results confirm that the presence of unconjugated beta-boldenone and alpha-boldenone conjugates next to alpha-boldenone are no indicators for illegal administration of boldenone-esters. No indications were obtained that conjugated beta-boldenone can be of endogenous origin.
Silicon carbide fibers and articles including same
Garnier, John E; Griffith, George W
2015-01-27
Methods of producing silicon carbide fibers. The method comprises reacting a continuous carbon fiber material and a silicon-containing gas in a reaction chamber at a temperature ranging from approximately 1500.degree. C. to approximately 2000.degree. C. A partial pressure of oxygen in the reaction chamber is maintained at less than approximately 1.01.times.10.sup.2 Pascal to produce continuous alpha silicon carbide fibers. Continuous alpha silicon carbide fibers and articles formed from the continuous alpha silicon carbide fibers are also disclosed.
2007-07-01
primary and secondary alpha in micrographs and thus to correlate microstructural features and texture data [3- 6 ]. For instance, Germain, et al. [3, 4 ...Following electropolishing , the sample was mounted 7/3/2007 6 on the tilting stage inside an XL30 field-emission-gun scanning-electron-microscope (FEG...AFRL-RX-WP-TP-2008-4338 A COUPLED EBSD/EDS METHOD TO DETERMINE THE PRIMARY–AND SECONDARY–ALPHA TEXTURES IN TITANIUM ALLOYS WITH DUPLEX
Van Boven, M; Leyssen, T; Busson, R; Holser, R; Cokelaere, M; Flo, G; Decuypere, E
2001-09-01
The isolation and identification of two pinitol alpha-D-galactosides from jojoba meal are described. The products were isolated by a combination of preparative HPLC on silica gel and TLC on amino silica gel and were identified by MS, NMR spectroscopy, and chemical derivatization as 5-O-(alpha-D-galactopyranosyl)-3-O-methyl-D-chiro-inositol or 5-alpha-D-galactopyranosyl-D-pinitol and 2-O-(alpha-D-galactopyranosyl)-3-O-methyl-D-chiro-inositol or 2-alpha-D-galactopyranosyl-D-pinitol. The same preparative HPLC method on silica gel allowed a new simmondsin derivative to be isolated and identified as 4,5-didemethyl-4-O-alpha-D-glucopyranosylsimmondsin mainly by NMR spectroscopy and high-resolution mass spectrometry.
Synthesis of peptide .alpha.-thioesters
Camarero, Julio A [Livermore, CA; Mitchell, Alexander R [Livermore, CA; De Yoreo, James J [Clayton, CA
2008-08-19
Disclosed herein is a new method for the solid phase peptide synthesis (SPPS) of C-terminal peptide .alpha. thioesters using Fmoc/t-Bu chemistry. This method is based on the use of an aryl hydrazine linker, which is totally stable to conditions required for Fmoc-SPPS. When the peptide synthesis has been completed, activation of the linker is achieved by mild oxidation. The oxidation step converts the acyl-hydrazine group into a highly reactive acyl-diazene intermediate which reacts with an .alpha.-amino acid alkylthioester (H-AA-SR) to yield the corresponding peptide .alpha.-thioester in good yield. A variety of peptide thioesters, cyclic peptides and a fully functional Src homology 3 (SH3) protein domain have been successfully prepared.
Alpha voltaic batteries and methods thereof
NASA Technical Reports Server (NTRS)
Jenkins, Phillip (Inventor); Scheiman, David (Inventor); Castro, Stephanie (Inventor); Raffaelle, Ryne P. (Inventor); Wilt, David (Inventor); Chubb, Donald (Inventor)
2011-01-01
An alpha voltaic battery includes at least one layer of a semiconductor material comprising at least one p/n junction, at least one absorption and conversion layer on the at least one layer of semiconductor layer, and at least one alpha particle emitter. The absorption and conversion layer prevents at least a portion of alpha particles from the alpha particle emitter from damaging the p/n junction in the layer of semiconductor material. The absorption and conversion layer also converts at least a portion of energy from the alpha particles into electron-hole pairs for collection by the one p/n junction in the layer of semiconductor material.
Unified studies of the structure changes and the nuclear reactions in {sup 10}Be
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ito, Makoto
2006-08-14
The {alpha}+6He low-energy reactions and the structural changes of 10Be in the microscopic {alpha}+{alpha}+N+N model are studied by the generalized two-center cluster model with the Kohn-Hulthen-Kato variation method. It is found that, in the inelastic scattering to the {alpha}+{sup 6}He(2{sub 1}{sup +}) channel, characteristic enhancements are expected as the results of the parity-dependent non-adiabatic dynamics. The reaction mechanism in breakup of 10Be into the {alpha}+6He continuum is also discussed.
Flavonoids from the flowers of Aesculus hippocastanum.
Dudek-Makuch, Marlena; Matławska, Irena
2011-01-01
The flavonoids, kaempferol derivatives: 3-O-alpha-arabinofuranoside, 3-O-beta-glucopyranoside, 3-O-alpha-rhamnopyranoside, 3-O-alpha-rhamnopyranosyl (1 --> 6)-O-beta-glucopyranoside and quercetin derivatives: 3-O-alpha-arabinofuranoside, 3-O-beta-glucopyranoside, 3-O-alpha-rhamnopyranosyl (1 --> 6)-O-beta-glucopyranoside, were isolated from the flowers of Aesculus hippocastanum and identified. The structures of these compounds were confirmed by a chemical analysis and spectrophotometric methods (UV, 1H-, 13C-NMR, ESI-MS). The presence of free aglycones: kaempferol and quercetin was confirmed chromatographically by comparison with standards.
The effect of particle size on the dehydration/rehydration behaviour of lactose.
Crisp, J L; Dann, S E; Edgar, M; Blatchford, C G
2010-05-31
Ethanolic suspensions of spray dried and micronized alpha lactose monohydrate (L(alpha)xH(2)O) with average particle size between 3 and 200 microm, have been prepared and their dehydration behaviour was investigated by (13)C CP-MASNMR spectroscopy. Sub-micron lactose suspension prepared by a novel high pressure homogenisation method has been compared with the standard ethanolic suspensions of (L(alpha).H(2)O prepared by reflux or static room temperature methods. In all cases, suspensions were shown to contain the stable anhydrous form of lactose ((L(alpha)(S)). Several approaches were employed to remove ethanol from these suspensions and the resulting dry lactose powders were then analysed by FT-IR, PXRD and SEM to evaluate the effect of drying procedure on type and distribution of lactose polymorphs and particle size. For samples with mean particle size greater than 1 microm, the stable anhydrous polymorphic form of lactose was retained on removal of the ethanol, although differences in the morphology and particle size of the crystals were apparent depending on method of suspension formation. Sub-micron (L(alpha)(S), while stable in dry conditions, has been shown to be less stable to atmospheric water vapour than (L(alpha)(S) with particle size between 3 and 200 microm. Copyright (c) 2010 Elsevier B.V. All rights reserved.
Method for high specific bioproductivity of .alpha.,.omega.-alkanedicarboxylic acids
Mobley, David Paul; Shank, Gary Keith
2000-01-01
This invention provides a low-cost method of producing .alpha.,.omega.-alkanedicarboxylic acids. Particular bioconversion conditions result in highly efficient conversion of fatty acid, fatty acid ester, or alkane substrates to diacids. Candida tropicalis AR40 or similar yeast strains are grown in a medium containing a carbon source and a nitrogen source at a temperature of 31.degree. C. to 38.degree. C., while additional carbon source is continuously added, until maximum cell growth is attained. Within 0-3 hours of this point, substrate is added to the culture to initiate conversion. An .alpha.,.omega.-alkanedicarboxylic acid made according to this method is also provided.
Cueto-Rojas, H F; Pérez, N O; Pérez-Sánchez, G; Ocampo-Juárez, I; Medina-Rivero, E
2010-04-15
Interferon-alpha 2b (IFN-alpha 2b) is a recombinant therapeutic cytokine produced as inclusion bodies using a strain of Escherichia coli as expression system. After fermentation and recovery, it is necessary to know the amount of recombinant IFN-alpha 2b, in order to determine the yield and the load for solubilization, and chromatographic protein purification steps. The present work details the validation of a new short run-time and fast sample-preparation method to quantify IFN-alpha 2b in inclusion bodies using Reversed Phase-Ultra Performance Liquid Chromatography (RP-UPLC). The developed method demonstrated an accuracy of 100.28%; the relative standard deviations for method precision, repeatability and inter-day precision tests were found to be 0.57%, 1.54% and 1.83%, respectively. Linearity of the method was assessed in the range of concentrations from 0.05 mg/mL to 0.5 mg/mL, the curve obtained had a determination coefficient (r(2)) of 0.9989. Detection and quantification limits were found to be 0.008 mg/mL and 0.025 mg/mL, respectively. The method also demonstrated robustness for changes in column temperature, and specificity against host proteins and other recombinant protein expressed in the same E. coli strain. Copyright 2010 Elsevier B.V. All rights reserved.
Device and method for accurately measuring concentrations of airborne transuranic isotopes
McIsaac, Charles V.; Killian, E. Wayne; Grafwallner, Ervin G.; Kynaston, Ronnie L.; Johnson, Larry O.; Randolph, Peter D.
1996-01-01
An alpha continuous air monitor (CAM) with two silicon alpha detectors and three sample collection filters is described. This alpha CAM design provides continuous sampling and also measures the cumulative transuranic (TRU), i.e., plutonium and americium, activity on the filter, and thus provides a more accurate measurement of airborne TRU concentrations than can be accomplished using a single fixed sample collection filter and a single silicon alpha detector.
Device and method for accurately measuring concentrations of airborne transuranic isotopes
McIsaac, C.V.; Killian, E.W.; Grafwallner, E.G.; Kynaston, R.L.; Johnson, L.O.; Randolph, P.D.
1996-09-03
An alpha continuous air monitor (CAM) with two silicon alpha detectors and three sample collection filters is described. This alpha CAM design provides continuous sampling and also measures the cumulative transuranic (TRU), i.e., plutonium and americium, activity on the filter, and thus provides a more accurate measurement of airborne TRU concentrations than can be accomplished using a single fixed sample collection filter and a single silicon alpha detector. 7 figs.
Orr, Christopher Henry; Luff, Craig Janson; Dockray, Thomas; Macarthur, Duncan Whittemore; Bounds, John Alan; Allander, Krag
2002-01-01
The apparatus and method provide techniques through which both alpha and beta emission determinations can be made simultaneously using a simple detector structure. The technique uses a beta detector covered in an electrically conducting material, the electrically conducting material discharging ions generated by alpha emissions, and as a consequence providing a measure of those alpha emissions. The technique also offers improved mountings for alpha detectors and other forms of detectors against vibration and the consequential effects vibration has on measurement accuracy.
Crompton, Anita J; Gamage, Kelum A A; Bell, Steven; Wilson, Andrew P; Jenkins, Alex; Trivedi, Divyesh
2017-11-29
In this work, a robust stand-off alpha detection method using the secondary effects of alpha radiation has been sought. Alpha particles ionise the surrounding atmosphere as they travel. Fluorescence photons produced as a consequence of this can be used to detect the source of the alpha emissions. This paper details experiments carried out to detect this fluorescence, with the focus on photons in the ultraviolet C (UVC) wavelength range (180-280 nm). A detector, UVTron R9533 (Hamamatsu, 325-6, Sunayama-cho, Naka-ku, Hamamatsu City, Shizuoka Pref., 430-8587, Japan), designed to detect the UVC emissions from flames for fire alarm purposes, was tested in various gas atmospheres with a 210 Po alpha source to determine if this could provide an avenue for stand-off alpha detection. The results of the experiments show that this detector is capable of detecting alpha-induced air fluorescence in normal indoor lighting conditions, as the interference from daylight and artificial lighting is less influential on this detection system which operates below the UVA and UVB wavelength ranges (280-315 nm and 315-380 nm respectively). Assuming a standard 1 r 2 drop off in signal, the limit of detection in this configuration can be calculated to be approximately 240 mm, well beyond the range of alpha-particles in air, which indicates that this approach could have potential for stand-off alpha detection. The gas atmospheres tested produced an increase in the detector count, with xenon having the greatest effect with a measured 52% increase in the detector response in comparison to the detector response in an air atmosphere. This type of alpha detection system could be operated at a distance, where it would potentially provide a more cost effective, safer, and faster solution in comparison with traditional alpha detection methods to detect and characterise alpha contamination in nuclear decommissioning and security applications.
Crompton, Anita J.; Wilson, Andrew P.; Jenkins, Alex; Trivedi, Divyesh
2017-01-01
In this work, a robust stand-off alpha detection method using the secondary effects of alpha radiation has been sought. Alpha particles ionise the surrounding atmosphere as they travel. Fluorescence photons produced as a consequence of this can be used to detect the source of the alpha emissions. This paper details experiments carried out to detect this fluorescence, with the focus on photons in the ultraviolet C (UVC) wavelength range (180–280 nm). A detector, UVTron R9533 (Hamamatsu, 325-6, Sunayama-cho, Naka-ku, Hamamatsu City, Shizuoka Pref., 430-8587, Japan), designed to detect the UVC emissions from flames for fire alarm purposes, was tested in various gas atmospheres with a 210Po alpha source to determine if this could provide an avenue for stand-off alpha detection. The results of the experiments show that this detector is capable of detecting alpha-induced air fluorescence in normal indoor lighting conditions, as the interference from daylight and artificial lighting is less influential on this detection system which operates below the UVA and UVB wavelength ranges (280–315 nm and 315–380 nm respectively). Assuming a standard 1r2 drop off in signal, the limit of detection in this configuration can be calculated to be approximately 240 mm, well beyond the range of alpha-particles in air, which indicates that this approach could have potential for stand-off alpha detection. The gas atmospheres tested produced an increase in the detector count, with xenon having the greatest effect with a measured 52% increase in the detector response in comparison to the detector response in an air atmosphere. This type of alpha detection system could be operated at a distance, where it would potentially provide a more cost effective, safer, and faster solution in comparison with traditional alpha detection methods to detect and characterise alpha contamination in nuclear decommissioning and security applications. PMID:29186051
Method of and apparatus for measuring the mean concentration of thoron and/or radon in a gas mixture
Lucas, Henry
1990-01-01
A method of and an apparatus for detecting and accurately measuring the mean concentrations of .sup.222 Rn and .sup.220 Tn in a gas mixture, such as the ambient atmosphere in a mine, is provided. The apparatus includes an alpha target member which defines at least one operative target surface and which is preferably fabricated from a single piece of an alpha particle sensitive material. At least one portion of the operative target surface is covered with an alpha particle filter. The uncovered and filter covered operative surface is exposed to the gas mixture containing the .sup.222 Rn and .sup.220 Tn. In the radioactive decay series of these isotopes the maximum kinetic energy emitted by the alpha decay of .sup.222 Rn is about 1.1 MeV less than the maximum kinetic energy emitted by the alpha decay of a .sup.220 Tn. The alpha particle filter has a predetermined mass per unit area of the covered portion of the operative target surface that prevents penetration of alpha particles which originate from .sup.222 Rn decay, but which allows passage therethrough of the maximum kinetic energy alpha particles from .sup.220 Tn decay. Thus, a count of the alpha particle tracks in the uncovered portion of the target member is proportional to the mean concentration of sum of .sup.222 Rn and .sup.220 Tn in the gas mixture, while the count of alpha tracks in the target member under the filter is proportional to the concentration of only the .sup.220 Tn in the gas mixture.
Liver alpha-amylase gene expression as an early obesity biomarker.
Mojbafan, Marzieh; Afsartala, Zohreh; Amoli, Mahsa M; Mahmoudi, Mahdi; Yaghmaei, Parichehreh; Larijani, Bagher; Ebrahim-Habibi, Azadeh
2017-04-01
Obesity is a major health problem worldwide, for which preventive and therapeutic means are still needed. Alpha-amylase is a digestive enzyme whose inhibition has been targeted as a potential anti-obesity strategy. However, alpha-amylase gene expression has not been particularly attended to, and in contrast with pancreatic and salivary amylases, fewer studies have focused on liver alpha-amylase. The present study aimed at investigating the expression of alpha-amylase gene in obese and normal mice at RNA and protein level as well as acarbose effect on this gene expression in hepatocyte cell culture. Control and case groups were fed by normal mouse pellet and high-fat diet respectively, during 8 weeks. After this period, serum biochemical parameters including glucose, cholesterol, triglycerides, AST, ALT and alpha-amylase were assayed. Liver alpha-amylase gene was analyzed by real time PCR, and liver enzyme was assayed with Bernfeld and ELISA methods Hepatocyte cell culture derived from both group were also treated by acarbose and alpha-amylase activity and gene expression was analyzed by above mentioned methods. All biochemical factors showed an increase in obese mice, but the increase in ALT and AST were not statistically significant. Alpha-amylase levels were also increased in obese mice, both at RNA and protein level, while a decrease was seen in obese mice derived hepatocytes after acarbose treatment. Elevated liver alpha-amylase levels may be indicative of initial stages of obesity and the use of acarbose could be considered as a treatment of obesity which could be potentially effective at multiple levels. Copyright © 2016. Published by Elsevier Urban & Partner Sp. z o.o.
Rossi-Arnaud, Clelia; Spataro, Pietro; Marques, Valeria R S; Longobardi, Emiddia
2015-03-01
Previous studies have indicated that pointing toward to-be-remembered visuospatial patterns enhances short-term memory (STM) when the presentation of pointing and no-pointing trials is mixed (Chum et al., 2007; Dodd & Shumborski, 2009; Rossi-Arnaud et al., 2012). By contrast, when presentation is blocked, pointing has inhibitory effects on memory (Dodd & Shumborski, 2009; Rossi-Arnaud et al., 2012). In the present study, we demonstrated that pointing has different effects on short-term recollection- and familiarity-based judgments, depending on the length of the visuospatial patterns (5- vs. 7-item arrays) and the interval between the encoding and test phases (2 vs. 5 s). More specifically, pointing decreased the accuracy of recollection-based judgments for 5-item arrays, but not for 7-item arrays (this negative effect did not interact with interval length). In contrast, pointing facilitated familiarity-based judgments when the interval between the study and test phases was 5 s, but not when it was 2 s (this positive effect did not interact with pattern length). We proposed that the negative effects might be accounted for by the simultaneous recruitment of attention resources in the planning and execution of pointing movements. As a consequence, executive resources are diverted from the primary memory task, resulting in a less efficient use of attention-demanding retrieval strategies, like chunking. By contrast, the positive effects on familiarity judgments might reflect the unitization of the to-be-remembered items into a single shape. (PsycINFO Database Record (c) 2015 APA, all rights reserved).
NASA Astrophysics Data System (ADS)
Marchi, Susanna; Guidotti, Diego; Ricciolini, Massimo; Petacchi, Ruggero
2016-11-01
Insect dynamics depend on temperature patterns, and therefore, global warming may lead to increasing frequencies and intensities of insect outbreaks. The aim of this work was to analyze the dynamics of the olive fruit fly, Bactrocera oleae (Rossi), in Tuscany (Italy). We profited from long-term records of insect infestation and weather data available from the regional database and agrometeorological network. We tested whether the analysis of 13 years of monitoring campaigns can be used as basis for prediction models of B. oleae infestation. We related the percentage of infestation observed in the first part of the host-pest interaction and throughout the whole year to agrometeorological indices formulated for different time periods. A two-step approach was adopted to inspect the effect of weather on infestation: generalized linear model with a binomial error distribution and principal component regression to reduce the number of the agrometeorological factors and remove their collinearity. We found a consistent relationship between the degree of infestation and the temperature-based indices calculated for the previous period. The relationship was stronger with the minimum temperature of winter season. Higher infestation was observed in years following warmer winters. The temperature of the previous winter and spring explained 66 % of variance of early-season infestation. The temperature of previous winter and spring, and current summer, explained 72 % of variance of total annual infestation. These results highlight the importance of multiannual monitoring activity to fully understand the dynamics of B. oleae populations at a regional scale.
Marchi, Susanna; Guidotti, Diego; Ricciolini, Massimo; Petacchi, Ruggero
2016-11-01
Insect dynamics depend on temperature patterns, and therefore, global warming may lead to increasing frequencies and intensities of insect outbreaks. The aim of this work was to analyze the dynamics of the olive fruit fly, Bactrocera oleae (Rossi), in Tuscany (Italy). We profited from long-term records of insect infestation and weather data available from the regional database and agrometeorological network. We tested whether the analysis of 13 years of monitoring campaigns can be used as basis for prediction models of B. oleae infestation. We related the percentage of infestation observed in the first part of the host-pest interaction and throughout the whole year to agrometeorological indices formulated for different time periods. A two-step approach was adopted to inspect the effect of weather on infestation: generalized linear model with a binomial error distribution and principal component regression to reduce the number of the agrometeorological factors and remove their collinearity. We found a consistent relationship between the degree of infestation and the temperature-based indices calculated for the previous period. The relationship was stronger with the minimum temperature of winter season. Higher infestation was observed in years following warmer winters. The temperature of the previous winter and spring explained 66 % of variance of early-season infestation. The temperature of previous winter and spring, and current summer, explained 72 % of variance of total annual infestation. These results highlight the importance of multiannual monitoring activity to fully understand the dynamics of B. oleae populations at a regional scale.
TWELVE AND A HALF YEARS OF OBSERVATIONS OF CENTAURUS A WITH THE ROSSI X-RAY TIMING EXPLORER
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rothschild, R. E.; Markowitz, A.; Rivers, E.
2011-05-20
The Rossi X-ray Timing Explorer (RXTE) has observed the nearest radio galaxy, Centaurus A (Cen A), in 13 intervals from 1996 August to 2009 February over the 3-200 keV band. Spectra accumulated over the 13 intervals were well described with an absorbed power law and an iron line. Cutoff power laws and Compton reflection from cold matter did not provide a better description. For the 2009 January observation, we set a lower limit on the cutoff energy at over 2 MeV. The power spectral density function was generated from RXTE/All Sky Monitor and Proportional Counter Array data as well asmore » an XMM-Newton long look, and clear evidence for a break at 18{sup +18}{sub -7} days (68% conf.) was seen. Given Cen A's high black hole mass and very low value of L{sub X}/L{sub Edd}, the break was a factor of 17{sup +36}{sub -13} times higher than the break frequency predicted by the McHardy et al. relation, which was empirically derived for a sample of objects, which are radio-quiet and accreting at relatively high values of L{sub bol}/L{sub Edd}. We have interpreted our observations in the context of a clumpy molecular torus. The variability characteristics and the broadband spectral energy distribution, when compared to Seyferts, imply that the bright hard X-ray continuum emission may originate at the base of the jet, yet from behind the absorbing line-of-sight material, in contrast to what is commonly observed from blazars.« less
NASA Astrophysics Data System (ADS)
Runnova, A. E.; Zhuravlev, M. O.; Khramova, M. V.; Pysarchik, A. N.
2017-04-01
We study the appearance, development and depression of the alpha-rhythm in human EEG data during a psychophysiological experiment by stimulating cognitive activity with the perception of ambiguous object. The new method based on continuous wavelet transform allows to estimate the energy contribution of various components, including the alpha rhythm, in the general dynamics of the electrical activity of the projections of various areas of the brain. The decision-making process by observe ambiguous images is characterized by specific oscillatory alfa-rhytm patterns in the multi-channel EEG data. We have shown the repeatability of detected principles of the alpha-rhythm evolution in a data of group of 12 healthy male volunteers.
Efficacy of alpha-chlorhydrin in sewer rat control.
Andrews, R. V.; Belknap, R. W.
1983-01-01
A single application of the male chemosterilant, alpha-chlorhydrin, to a problem sewer rat infestation resulted in reductions of rat numbers and distribution which was comparable to effects of warfarin baiting methods. Rat numbers were reduced by more than 85% by both methods. More rapid mortality and recruitment were evident for warfarin effects; the alpha-chlorhydrin treated population had a longer lag phase of growth so that reinfestation of sewer habitat to pre-treatment numbers, and distribution over a 40 square block area, required approximately 1.5-2 times longer after alpha-chlorhydrin treatment when compared with warfarin treatment. Comparisons of changes in rat densities in infested sewers following the two treatments indicate that recovery of warfarin treated populations is achieved by reproductive recruitment followed by dispersal while alpha-chlorhydrin treated populations recover by slower immigration and later reproductive recruitment. Alpha-chlorohydrin should be a useful addition to a limited arsenal of rat control agents because of its specificity for the Norway rat, its single dose effectiveness as a toxicant-chemosterilant, and its short environmental half-life. PMID:6644013
NASA Astrophysics Data System (ADS)
Carlsohn, Elisabet; Ångström, Jonas; Emmett, Mark R.; Marshall, Alan G.; Nilsson, Carol L.
2004-05-01
Chemical cross-linking of proteins is a well-established method for structural mapping of small protein complexes. When combined with mass spectrometry, cross-linking can reveal protein topology and identify contact sites between the peptide surfaces. When applied to surface-exposed proteins from pathogenic organisms, the method can reveal structural details that are useful in vaccine design. In order to investigate the possibilities of applying cross-linking on larger protein complexes, we selected the urease enzyme from Helicobacter pylori as a model. This membrane-associated protein complex consists of two subunits: [alpha] (26.5 kDa) and [beta] (61.7 kDa). Three ([alpha][beta]) heterodimers form a trimeric ([alpha][beta])3 assembly which further associates into a unique dodecameric 1.1 MDa complex composed of four ([alpha][beta])3 units. Cross-linked peptides from trypsin-digested urease complex were analyzed by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) and molecular modeling. Two potential cross-linked peptides (present in the cross-linked sample but undetectable in [alpha], [beta], and native complex) were assigned. Molecular modeling of urease [alpha][beta] complex and trimeric urease units ([alpha][beta])3 revealed a linkage site between the [alpha]-subunit and the [beta]-subunit, and an internal cross-linkage in the [beta]-subunit.
Li, Minyong; Xia, Lin
2007-11-01
In the present report, a novel series of 1-indanone alpha(1)-adrenoceptor antagonists were designed and synthesized based on 3D-pharmacophore model. Their in vitro alpha(1)-adrenoceptor antagonistic assay showed that three compounds (2a, 2m, and 2o) had similar or improved alpha(1)-adrenoceptor antagonistic activities relative to the positive control prazosin. Based on these results, a three-dimensional quantitative structure-activity relationship study was performed using a Self-Organizing Molecular Field Analysis method to provide insight for the future development of alpha(1)-adrenoceptor antagonists.
Hinchliffe, Edward; Rudge, James; Reed, Paul
2016-07-01
Measurement of vitamin A (retinol) and E (alpha-tocopherol) in UK clinical laboratories is currently performed exclusively by high-performance liquid chromatography with ultraviolet detection. We investigated whether retinol and alpha-tocopherol could be measured simultaneously by liquid chromatography tandem mass spectrometry. Serum samples (100 μL) were extracted using Isolute + Supported Liquid Extraction plates. Chromatography was performed on a Phenomenex Kinetex Biphenyl 2.6 μm, 50 × 2.1 mm column, and liquid chromatography tandem mass spectrometry on a Waters Acquity TQD. Injection-to-injection time was 4.3 min. The assay was validated according to published guidelines. Patient samples were used to compare liquid chromatography tandem mass spectrometry and high-performance liquid chromatography with ultraviolet detection methods. For retinol and alpha-tocopherol, respectively, the assay was linear up to 6.0 and 80.0 μmol/L, and lower limit of quantification was 0.07 and 0.26 μmol/L. Intra and interassay imprecision were within desirable analytical specifications. Analysis of quality control material aligned to NIST SRM 968e, and relative spiked recovery from human serum, both yielded results within 15% of target values. Method comparison with high-performance liquid chromatography with ultraviolet detection methodology demonstrated a negative bias for retinol and alpha-tocopherol by the liquid chromatography tandem mass spectrometry method. Analysis of United Kingdom National External Quality Assurance Scheme samples yielded mean bias from the target value of +3.0% for retinol and -11.2% for alpha-tocopherol. We have developed a novel, high-throughput method for extraction of retinol and alpha-tocopherol from human serum followed by simultaneous quantitation by liquid chromatography tandem mass spectrometry. The method offers a rapid, sensitive, specific and cost-effective alternative to high-performance liquid chromatography with ultraviolet detection methodology, and is suitable for routine clinical monitoring of patients predisposed to fat-soluble vitamin malabsorption. © The Author(s) 2015.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Maxwell, S.; Jones, V.
2009-05-27
A new rapid separation method that allows separation and preconcentration of actinides in urine samples was developed for the measurement of longer lived actinides by inductively coupled plasma mass spectrometry (ICP-MS) and short-lived actinides by alpha spectrometry; a hybrid approach. This method uses stacked extraction chromatography cartridges and vacuum box technology to facilitate rapid separations. Preconcentration, if required, is performed using a streamlined calcium phosphate precipitation. Similar technology has been applied to separate actinides prior to measurement by alpha spectrometry, but this new method has been developed with elution reagents now compatible with ICP-MS as well. Purified solutions are splitmore » between ICP-MS and alpha spectrometry so that long- and short-lived actinide isotopes can be measured successfully. The method allows for simultaneous extraction of 24 samples (including QC samples) in less than 3 h. Simultaneous sample preparation can offer significant time savings over sequential sample preparation. For example, sequential sample preparation of 24 samples taking just 15 min each requires 6 h to complete. The simplicity and speed of this new method makes it attractive for radiological emergency response. If preconcentration is applied, the method is applicable to larger sample aliquots for occupational exposures as well. The chemical recoveries are typically greater than 90%, in contrast to other reported methods using flow injection separation techniques for urine samples where plutonium yields were 70-80%. This method allows measurement of both long-lived and short-lived actinide isotopes. 239Pu, 242Pu, 237Np, 243Am, 234U, 235U and 238U were measured by ICP-MS, while 236Pu, 238Pu, 239Pu, 241Am, 243Am and 244Cm were measured by alpha spectrometry. The method can also be adapted so that the separation of uranium isotopes for assay is not required, if uranium assay by direct dilution of the urine sample is preferred instead. Multiple vacuum box locations may be set-up to supply several ICP-MS units with purified sample fractions such that a high sample throughput may be achieved, while still allowing for rapid measurement of short-lived actinides by alpha spectrometry.« less
Morvan, F; Rayner, B; Imbach, J L; Thenet, S; Bertrand, J R; Paoletti, J; Malvy, C; Paoletti, C
1987-01-01
This paper describes for the first time the synthesis of alpha-oligonucleotides containing the four usual bases. Two unnatural hexadeoxyribonucleotides: alpha-[d(CpApTpGpCpG)] and alpha-[d(CpGpCpApTpG)], consisting only of alpha-anomeric nucleotide units, were obtained by an improved phosphotriester method, in solution. Starting material was the four base-protected alpha-deoxyribonucleosides 3a-d. Pyrimidine alpha-deoxynucleosides 3a and 3b were prepared by self-anomerization reactions followed by selective deprotection of sugar hydroxyles, while the two purine alpha-deoxynucleosides 3c and 3d were prepared by glycosylation reactions. In the case of guanine alpha-nucleoside derivative a supplementary base-protecting group: N,N-diphenylcarbamoyl was introduced on O6-position in order to avoid side-reactions during oligonucleotide assembling. The hexadeoxynucleotide alpha-[d(CpApTpGpCpG)] was tested as substrate of selected endo- and exonucleases. In conditions where the natural corresponding beta-hexamer was completely degradated by nuclease S1 and calf spleen phosphodiesterase, the alpha-oligonucleotide remained almost intact. PMID:3575096
Nicoletti, I; Corradini, C; Cogliandro, E; Cavazza, A
1999-08-01
This paper reports the results of a study carried out to develop a simple, rapid and sensitive method for the separation, identification and quantitative measurement of alpha-hydroxy acids in commercial cosmetics using high-performance liquid chromatography (HPLC). This method is successfully applied to the simultaneous identification and quantitative determination of glycolic, lactic, malic, tartaric and citric acids employing a reversed phase narrow-bore column under isocratic condition and UV detection. The method is validated by determining the precision of replicate analyses and accuracy by analyzing samples with and without adding know amount of the alpha-hydroxy acids. The procedure is suitable for routine analyses of commercial cosmetics.
Newton-like methods for Navier-Stokes solution
NASA Astrophysics Data System (ADS)
Qin, N.; Xu, X.; Richards, B. E.
1992-12-01
The paper reports on Newton-like methods called SFDN-alpha-GMRES and SQN-alpha-GMRES methods that have been devised and proven as powerful schemes for large nonlinear problems typical of viscous compressible Navier-Stokes solutions. They can be applied using a partially converged solution from a conventional explicit or approximate implicit method. Developments have included the efficient parallelization of the schemes on a distributed memory parallel computer. The methods are illustrated using a RISC workstation and a transputer parallel system respectively to solve a hypersonic vortical flow.
Morphological characterization of the AlphaA- and AlphaB-crystallin double knockout mouse lens
Boyle, Daniel L; Takemoto, Larry; Brady, James P; Wawrousek, Eric F
2003-01-01
Background One approach to resolving some of the in vivo functions of alpha-crystallin is to generate animal models where one or both of the alpha-crystallin gene products have been eliminated. In the single alpha-crystallin knockout mice, the remaining alpha-crystallin may fully or partially compensate for some of the functions of the missing protein, especially in the lens, where both alphaA and alphaB are normally expressed at high levels. The purpose of this study was to characterize gross lenticular morphology in normal mice and mice with the targeted disruption of alphaA- and alphaB-crystallin genes (alphaA/BKO). Methods Lenses from 129SvEvTac mice and alphaA/BKO mice were examined by standard scanning electron microscopy and confocal microscopy methodologies. Results Equatorial and axial (sagittal) dimensions of lenses for alphaA/BKO mice were significantly smaller than age-matched wild type lenses. No posterior sutures or fiber cells extending to the posterior capsule of the lens were found in alphaA/BKO lenses. Ectopical nucleic acid staining was observed in the posterior subcapsular region of 5 wk and anterior subcapsular cortex of 54 wk alphaA/BKO lenses. Gross morphological differences were also observed in the equatorial/bow, posterior and anterior regions of lenses from alphaA/BKO mice as compared to wild mice. Conclusion These results indicated that both alphaA- and alphaB-crystallin are necessary for proper fiber cell formation, and that the absence of alpha-crystallin can lead to cataract formation. PMID:12546709
A Multicomponent UV Analysis of ["alpha"]- and ["beta"]-Acids in Hops
ERIC Educational Resources Information Center
Egts, Haley; Durben, Dan J.; Dixson, John A.; Zehfus, Micheal H.
2012-01-01
A method is presented for the determination of ["alpha"]- and ["beta"]-acids (humulones and lupulones) in a hops sample using a multicomponent UV spectroscopic analysis of a methanolic hop extract. When compared with standard methods, this lab can be considered "greener" because it uses smaller volumes of safer solvents (methanol instead of…
Lowe, J.B.; Lennon, G.; Rouquier, S.; Giorgi, D.; Kelly, R.J.
1998-09-15
The gene encoding GDP-L-fucose: {beta}-D-Galactoside 2-{alpha}-Lfucosyltransferase has been cloned, and a mutation in this gene has been found to be responsible for an individual being a non-secretor. 30 figs.
This report summarizes the development and validation of an improved method for the Determination of Gross Alpha and Gross Beta Activity in Flowback and Produced Waters from Hydraulic Fracturing Operations (FPWHFO). Flowback and produced waters are characterized by high concentra...
Lowe, John B.; Lennon, Gregory; Rouquier, Sylvie; Giorgi, Dominique; Kelly, Robert J.
1998-01-01
The gene encoding GDP-L-fucose: .beta.-D-Galactoside 2-.alpha.-L-fucosyltransferase has been cloned, and a mutation in this gene has been found to be responsible for an individual being a non-secretor.
Does preprocessing change nonlinear measures of heart rate variability?
Gomes, Murilo E D; Guimarães, Homero N; Ribeiro, Antônio L P; Aguirre, Luis A
2002-11-01
This work investigated if methods used to produce a uniformly sampled heart rate variability (HRV) time series significantly change the deterministic signature underlying the dynamics of such signals and some nonlinear measures of HRV. Two methods of preprocessing were used: the convolution of inverse interval function values with a rectangular window and the cubic polynomial interpolation. The HRV time series were obtained from 33 Wistar rats submitted to autonomic blockade protocols and from 17 healthy adults. The analysis of determinism was carried out by the method of surrogate data sets and nonlinear autoregressive moving average modelling and prediction. The scaling exponents alpha, alpha(1) and alpha(2) derived from the detrended fluctuation analysis were calculated from raw HRV time series and respective preprocessed signals. It was shown that the technique of cubic interpolation of HRV time series did not significantly change any nonlinear characteristic studied in this work, while the method of convolution only affected the alpha(1) index. The results suggested that preprocessed time series may be used to study HRV in the field of nonlinear dynamics.
Yu, L; Ishida, T; Ozawa, K; Akutsu, H; Horiike, K
2001-03-01
Two distinct forms of acetate kinase were purified to homogeneity from a sulfate-reducing bacterium Desulfovibrio vulgaris Miyazaki F. The enzymes were separated from the soluble fraction of the cells on anion exchange columns. One acetate kinase (AK-I) was a homodimer (alpha(S)(2)) and the other (AK-II) was a heterodimer (alpha(S)alpha(L)). On SDS-PAGE, alpha(L) and alpha(S) subunits migrated as bands of 49.3 and 47.8 kDa, respectively, but they had an identical N-terminal amino acid sequence. A rapid HPLC method was developed to directly measure ADP and ATP in assay mixtures. Initial velocity data for AK-I and AK-II were collected by this method and analyzed based on a random sequential mechanism, assuming rapid equilibrium for the substrate binding steps. All kinetic parameters for both the forward acetyl phosphate formation and the reverse ATP formation catalyzed by AK-I and AK-II were successfully determined. The two enzymes showed similar kinetic properties in Mg(2+) requirement, pH-dependence and magnitude of kinetic parameters. These results suggest that two forms of acetate kinase are produced to finely regulate the enzyme function by post-translational modifications of a primary gene product in Desulfovibrio vulgaris.
Ołdziej, S; Czaplewski, C; Liwo, A; Chinchio, M; Nanias, M; Vila, J A; Khalili, M; Arnautova, Y A; Jagielska, A; Makowski, M; Schafroth, H D; Kaźmierkiewicz, R; Ripoll, D R; Pillardy, J; Saunders, J A; Kang, Y K; Gibson, K D; Scheraga, H A
2005-05-24
Recent improvements in the protein-structure prediction method developed in our laboratory, based on the thermodynamic hypothesis, are described. The conformational space is searched extensively at the united-residue level by using our physics-based UNRES energy function and the conformational space annealing method of global optimization. The lowest-energy coarse-grained structures are then converted to an all-atom representation and energy-minimized with the ECEPP/3 force field. The procedure was assessed in two recent blind tests of protein-structure prediction. During the first blind test, we predicted large fragments of alpha and alpha+beta proteins [60-70 residues with C(alpha) rms deviation (rmsd) <6 A]. However, for alpha+beta proteins, significant topological errors occurred despite low rmsd values. In the second exercise, we predicted whole structures of five proteins (two alpha and three alpha+beta, with sizes of 53-235 residues) with remarkably good accuracy. In particular, for the genomic target TM0487 (a 102-residue alpha+beta protein from Thermotoga maritima), we predicted the complete, topologically correct structure with 7.3-A C(alpha) rmsd. So far this protein is the largest alpha+beta protein predicted based solely on the amino acid sequence and a physics-based potential-energy function and search procedure. For target T0198, a phosphate transport system regulator PhoU from T. maritima (a 235-residue mainly alpha-helical protein), we predicted the topology of the whole six-helix bundle correctly within 8 A rmsd, except the 32 C-terminal residues, most of which form a beta-hairpin. These and other examples described in this work demonstrate significant progress in physics-based protein-structure prediction.
Thermal diffusivity of alpha-mercuric iodide
NASA Astrophysics Data System (ADS)
Burger, A.; Morgan, S. H.; Henderson, D. O.; Silberman, E.; Nason, D.
1991-01-01
The thermal diffusivity and its anisotropy is measured along the principal axes of tetragonal alpha-HgI2 semiconductor single crystals grown from vapor. The experiments are carried out using the flash pulse method. The results show that alpha(100-line-type) = 0.00370 sq cm/s + or - 3 percent and alpha(001-line-type = 0.00103 sq cm/s + or - 10 percent. Necessary corrections are made for the experimental variables of heat losses and finite pulse duration in the data analysis.
Relating to monitoring ion sources
Orr, Christopher Henry; Luff, Craig Janson; Dockray, Thomas; Macarthur, Duncan Whittemore; Bounds, John Alan
2002-01-01
The apparatus and method provide techniques for monitoring the position on alpha contamination in or on items or locations. The technique is particularly applicable to pipes, conduits and other locations to which access is difficult. The technique uses indirect monitoring of alpha emissions by detecting ions generated by the alpha emissions. The medium containing the ions is moved in a controlled manner frog in proximity with the item or location to the detecting unit and the signals achieved over time are used to generate alpha source position information.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Puglia, S. M. R.; Lamia, L.; Romano, S.
2010-08-12
In this work the analysis of the {sup 10}B(23p, {alpha}){sup 7}Be and {sup 11}B(p, {alpha}){sup 8}Be reactions, studied via the indirect Trojan Horse Method (THM), is discussed. In the astrophysical context of light nuclei LiBeB depletion, the above mentioned reactions are the main responsible for the destruction of boron in the stellar interior. The THM application allows their investigation in the astrophysically relevant energy region, around the Gamow Peak ({approx_equal}10 keV), overcoming the problems due to the presence of the Coulomb barrier and electron screening effect. The experimental procedure and the preliminary results are shown.
Montgomery, Jill D; Hensler, Heather R; Jacobson, Lisa P; Jenkins, Frank J
2008-07-01
The aim of the present study was to determine if the Alpha DigiDoc RT system would be an effective method of quantifying immunohistochemical staining as compared with a manual counting method, which is considered the gold standard. Two readers were used to count 31 samples by both methods. The results obtained using the Bland-Altman for concordance deemed no statistical difference between the 2 methods. Thus, the Alpha DigiDoc RT system is an effective, low cost method to quantify immunohistochemical data.
Etnier, David A.; Parker, Charles R.; Baxter, John T.; Long, Todd M.
2010-01-01
Twenty-nine species of caddisflies in the genus Agapetus Curtis in eastern and central North America are reviewed. Twelve are described as new species: Agapetus aphallus (known only from females); Agapetus baueri, Agapetus flinti, Agapetus harrisi, Agapetus hesperus, Agapetus ibis, Agapetus kirchneri, Agapetus meridionalis, Agapetus pegram, Agapetus ruiteri, Agapetus stylifer, and Agapetus tricornutus. Agapetus rossi Denning 1941 is recognized as a junior subjective synonym of Agapetus walkeri (Betten and Mosely 1940), new synonym. A key to males is provided, and species’ distributions are mapped.
Burst Oscillations: A New Spin on Neutron Stars
NASA Technical Reports Server (NTRS)
Strohmayer, Tod
2007-01-01
Observations with NASA's Rossi X-ray Timing Explorer (RXTE) have shown that the X-ray flux during thermonuclear X-ray bursts fr-om accreting neutron stars is often strongly pulsed at frequencies as high as 620 Hz. We now know that these oscillations are produced by spin modulation of the thermonuclear flux from the neutron star surface. In addition to revealing the spin frequency, they provide new ways to probe the properties and physics of accreting neutron stars. I will briefly review our current observational and theoretical understanding of these oscillations and discuss what they are telling us about neutron stars.
NASA Technical Reports Server (NTRS)
Harmon, B. A.; Finger, M. H.; McCollough, M. L.; Zhang, S. N.; Paciesas, W. S.; Wilson, C. A.
1999-01-01
The x-ray transient XTE Jl550-564 (IAUC 7008) was detected in Burst and Transient Source Experiment (BATSE) data beginning on Jan. 21. As of Jan. 23. the one-day averaged flux was 300 mCrab (+/- 20 percent, 20-100 keV), with a hard spectrum (power-law photon-number index -2.3 +/- 0.2). This is a reflare in hard x-rays, following the primary outburst in 1998 Sept.-Oct. (IAUC 7010). The source has been active in soft x-rays (2-12 keV) since about Dec. 18, according to observations by the Rossi X-ray Timing Explorer ASM.
Use of /sup 3/He/sup + +/ ICRF minority heating to simulate alpha particle heating
Post, D.E. Jr.; Hwang, D.Q.; Hovey, J.
1983-11-16
It is an object of the present invention to provide a better understanding of alpha particle behavior in a magnetically confined, energetic plasma. Another object of the present invention is to provide an improved means and method for studying and measuring the energy distribution of heated alpha particles in a confined plasma. Yet another object of the present invention is to permit detailed analysis of energetic alpha particle behavior in a magnetically confined plasma for use in near term fusion reactor experiments. A still further object of the present invention is to simulate energetic alpha particle behavior in a deuterium-tritium plasma confined in a fusion reactor without producing the neutron activation associated with the thus produced alpha particles.
Yanagawa, K; Takeda, H; Matsumiya, T; Takasaki, M
1999-05-01
alpha-Tocopherol (alpha-Toc), a lipophilic phenolic antioxidant that is localized mainly in the biomembrane, protects cells against oxidation-associated cytotoxicity by prevention of membrane lipid peroxidation, maintenance of the redox balance intracellular thiols and stabilization of the membrane structure. We investigated the age-related changes in redox dynamics of alpha-Toc in plasma and erythrocyte membrane of an elderly (66 weeks old) and young group (10 weeks old). Total, alpha-, beta + gamma-, delta-Toc and alpha-tocopherolquinone (alpha-TocQ) in plasma and erythrocyte membrane were determined by high-performance liquid chromatography (HPLC) with a series of multiple coulometric working electrodes (CWE). Rat venous blood sample was divided into plasma and erythrocyte layers by centrifugation, and then erythrocyte membrane sample was prepared according to the method of Dodge et al. under a stream of nitrogen. In plasma, total and alpha-Toc concentrations were increased, and beta + gamma-, delta-Toc and alpha-TocQ concentrations were decreased age-dependently. In the erythrocyte membrane, total, alpha-TocQ concentrations and three fractions of tocopherols decreased age-dependently. Also, a decrease in the alpha-TocQ/alpha-Toc ratio in erythrocyte membrane was observed in the elderly group. These findings suggest that the alpha-Toc uptake in erythrocyte membrane and utilization rate of alpha-Toc in erythrocyte membrane decline age-dependently. This decline may promote membrane lipid peroxidation. alpha-Toc redox dynamics in erythrocyte membrane were useful to investigate the pathophysiology of aging mechanisms related to oxidative stress.
Soil water retention and maximum capillary drive from saturation to oven dryness
Morel-Seytoux, Hubert J.; Nimmo, John R.
1999-01-01
This paper provides an alternative method to describe the water retention curve over a range of water contents from saturation to oven dryness. It makes two modifications to the standard Brooks and Corey [1964] (B-C) description, one at each end of the suction range. One expression proposed by Rossi and Nimmo [1994] is used in the high-suction range to a zero residual water content. (This Rossi-Nimmo modification to the Brooks-Corey model provides a more realistic description of the retention curve at low water contents.) Near zero suction the second modification eliminates the region where there is a change in suction with no change in water content. Tests on seven soil data sets, using three distinct analytical expressions for the high-, medium-, and low-suction ranges, show that the experimental water retention curves are well fitted by this composite procedure. The high-suction range of saturation contributes little to the maximum capillary drive, defined with a good approximation for a soil water and air system as HcM = ∫0∞ Krwdhc , where krw is relative permeability (or conductivity) to water and hc is capillary suction, a positive quantity in unsaturated soils. As a result, the modification suggested to describe the high-suction range does not significantly affect the equivalence between Brooks-Corey (B-C) and van Genuchten [1980] parameters presented earlier. However, the shape of the retention curve near “natural saturation” has a significant impact on the value of the capillary drive. The estimate using the Brooks-Corey power law, extended to zero suction, will exceed that obtained with the new procedure by 25 to 30%. It is not possible to tell which procedure is appropriate. Tests on another data set, for which relative conductivity data are available, support the view of the authors that measurements of a retention curve coupled with a speculative curve of relative permeability as from a capillary model are not sufficient to accurately determine the (maximum) capillary drive. The capillary drive is a dynamic scalar, whereas the retention curve is of a static character. Only measurements of infiltration rates with time can determine the capillary drive with precision for a given soil.
Lee, Sandra W W; Clement, Naomi; Tang, Natalie; Atiomo, William
2014-12-01
To evaluate the current provision and outcome of community-based education (CBE) in UK medical schools. An online survey of UK medical school websites and course prospectuses and a systematic review of articles from PubMed and Web of Science were conducted. Articles in the systematic review were assessed using Rossi, Lipsey and Freeman's approach to programme evaluation. Publications from November 1998 to 2013 containing information related to community teaching in undergraduate medical courses were included. Out of the 32 undergraduate UK medical schools, one was excluded due to the lack of course specifications available online. Analysis of the remaining 31 medical schools showed that a variety of CBE models are utilised in medical schools across the UK. Twenty-eight medical schools (90.3%) provide CBE in some form by the end of the first year of undergraduate training, and 29 medical schools (93.5%) by the end of the second year. From the 1378 references identified, 29 papers met the inclusion criteria for assessment. It was found that CBE mostly provided advantages to students as well as other participants, including GP tutors and patients. However, there were a few concerns regarding the lack of GP tutors' knowledge in specialty areas, the negative impact that CBE may have on the delivery of health service in education settings and the cost of CBE. Despite the wide variations in implementation, community teaching was found to be mostly beneficial. To ensure the relevance of CBE for 'Tomorrow's Doctors', a national framework should be established, and solutions sought to reduce the impact of the challenges within CBE. This is the first study to review how community-based education is currently provided throughout Medical Schools in the UK. The use of Rossi, Lipsey and Freeman's method of programme evaluation means that the literature was analysed in a consistent and comprehensive way. However, a weakness is that data from the online survey was obtained from online medical school prospectuses. This means the data may be incomplete or out of date. Data in the literature review may also be skewed by publication bias. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Lee, Sandra W W; Clement, Naomi; Tang, Natalie; Atiomo, William
2014-01-01
Objective To evaluate the current provision and outcome of community-based education (CBE) in UK medical schools. Design and data sources An online survey of UK medical school websites and course prospectuses and a systematic review of articles from PubMed and Web of Science were conducted. Articles in the systematic review were assessed using Rossi, Lipsey and Freeman's approach to programme evaluation. Study selection Publications from November 1998 to 2013 containing information related to community teaching in undergraduate medical courses were included. Results Out of the 32 undergraduate UK medical schools, one was excluded due to the lack of course specifications available online. Analysis of the remaining 31 medical schools showed that a variety of CBE models are utilised in medical schools across the UK. Twenty-eight medical schools (90.3%) provide CBE in some form by the end of the first year of undergraduate training, and 29 medical schools (93.5%) by the end of the second year. From the 1378 references identified, 29 papers met the inclusion criteria for assessment. It was found that CBE mostly provided advantages to students as well as other participants, including GP tutors and patients. However, there were a few concerns regarding the lack of GP tutors’ knowledge in specialty areas, the negative impact that CBE may have on the delivery of health service in education settings and the cost of CBE. Conclusions Despite the wide variations in implementation, community teaching was found to be mostly beneficial. To ensure the relevance of CBE for ‘Tomorrow's Doctors’, a national framework should be established, and solutions sought to reduce the impact of the challenges within CBE. Strengths and limitations of this study This is the first study to review how community-based education is currently provided throughout Medical Schools in the UK. The use of Rossi, Lipsey and Freeman's method of programme evaluation means that the literature was analysed in a consistent and comprehensive way. However, a weakness is that data from the online survey was obtained from online medical school prospectuses. This means the data may be incomplete or out of date. Data in the literature review may also be skewed by publication bias. PMID:25448625
NASA Astrophysics Data System (ADS)
Rossi, Federico; Adessi, Alessandra; De Philippis, Roberto
2016-04-01
Biological soil crusts (BSCs) are complex communities commonly constituting organo-mineral layers in arid and semiarid environment having a major influence on these ecosystems (Belnap and Lange, 2001). They have high tolerance towards a-biotic stresses and fluctuations in moisture, illumination, salinity and nutrients. The plasticity exhibited by BSCs is hugely contributed by the presence of the extracellular polymeric matrix (EPM) that is synthesized by crustal organisms, notably cyanobacteria and microalgae. This polysaccharidic net plays key roles in biofilm relations with the surrounding constrained environment. Notably, EPM concurs in coping with water scarcity, freezing and salt stress; increases biolayers stability against erosion, and is involved in nutrient provision (Rossi and De Philippis, 2015). We conducted several investigations in a research area located in the Inner Mongolian desert (Inner Mongolia, China) where BSCs were induced over different sites through inoculation-based techniques performed in different years. Our studies were aimed at determining the role of EPM in BSC development and survival in such a hyper-arid system. This presentation will report the results concerning the role of EPM in water capture from non-rainfall sources, water maintenance at the topsoil, and in water infiltrability, the latter being a factor with important ecological implications. In additions we investigated the role of the matrix as a source of carbon for the crustal heterotrophs. Furthermore, EPM was extracted with methods optimized in our lab, aiming at removing tightly bound fractions and loosely bound fractions from BSCs having different ages. The fractions were analyzed in terms of monosaccharidic composition, and molecular weight (MW) distribution. We show how the relative amounts of uronic acids increase in the EPM with the age of the crusts, implying advantages for the community-water relations. In addition, we observed significant differences in MW distribution between EPM fractions and in relation to the age of the crusts, hinting at distinct roles of the same fractions within the crust system. References • Belnap, J., Lange, O.L. (Eds.), 2001. Biological soil crusts: structure, function, and management, Ecological studies. Springer, New York. • Rossi, F., De Philippis, R., 2015. Role of Cyanobacterial Exopolysaccharides in Phototrophic Biofilms and in Complex Microbial Mats. Life 5, 1218-1238. doi:10.3390/life5021218
2013-01-01
Background Nowadays long-lasting insecticidal mosquito nets (LNs) are frequently used around the world to protect people against malaria vectors. As they contain insecticide, laboratory control is needed to check whether the content of the active ingredient follows the conditions of the manufacturer and also if the active ingredient is still present after some time of use. For this purpose, an analytical method had to be developed. The fact that LNs include a range of polymers for the yarn and use coated or incorporated technologies for the active ingredient, it is a challenge to find only one analytical method determining the active ingredient in LNs, which takes into account both impregnation technologies. Some methods are provided by international organizations but are limited by the determination of only one pesticide per method. The aim of this study was to optimize a short time extraction method for deltamethrin and alpha-cypermethrin from coated and incorporated mosquito nets and also to detect both insecticides in one analytical run, using gas chromatography with electron capture detection (GC-μECD). Methods Based on the literature, the most suitable solvent and the adequate extraction process for the insecticides used for net making were identified and adapted for the new multi-residue method. Results The validation data of the multi-residue method to determine deltamethrin and alpha-cypermethrin in mosquito nets by GC-μECD are given. Depending on the concentration of the active ingredient spiked on the nets, the mean recovery for alpha-cypermethrin ranged between 86% and 107% with a relative standard deviation below 3.5%. For deltamethrin it ranged between 90% and 108% with a relative standard deviation also below 3.5%. The limit of detection is 0.009 g.a.i/kg of net (0.3 mg a.i./m2 of net) both for alpha-cypermethrin and deltamethrin. Conclusions Data obtained are excellent. A 30 minutes reflux extraction method with xylene was developed to determine alpha-cypermethrin and deltamethrin in long-lasting insecticidal mosquito nets (LNs) by gas chromatography with electron capture detection (GC-μECD). The method can be easily extended to others pyrethroid used for mosquito net treatment. This paper also presents an overview of the studies dealing with pesticide determination in mosquito nets. PMID:23514225
Kugland, Nathan; Doeppner, Tilo; Glenzer, Siegfried; Constantin, Carmen; Niemann, Chris; Neumayer, Paul
2015-04-07
A method is provided for characterizing spectrometric properties (e.g., peak reflectivity, reflection curve width, and Bragg angle offset) of the K.alpha. emission line reflected narrowly off angle of the direct reflection of a bent crystal and in particular of a spherically bent quartz 200 crystal by analyzing the off-angle x-ray emission from a stronger emission line reflected at angles far from normal incidence. The bent quartz crystal can therefore accurately image argon K.alpha. x-rays at near-normal incidence (Bragg angle of approximately 81 degrees). The method is useful for in-situ calibration of instruments employing the crystal as a grating by first operating the crystal as a high throughput focusing monochromator on the Rowland circle at angles far from normal incidence (Bragg angle approximately 68 degrees) to make a reflection curve with the He-like x-rays such as the He-.alpha. emission line observed from a laser-excited plasma.
Screening of a thiamine-auxotrophic yeast for alpha-ketoglutaric acid overproduction.
Zhou, Jingwen; Zhou, Haiyan; Du, Guocheng; Liu, Liming; Chen, Jian
2010-09-01
To obtain a thiamine-auxotrophic yeast strain that overproduces alpha-ketoglutaric acid (alpha-KG) from glycerol and to investigate nutrient effects on alpha-KG production. Yeast strain WSH-Z06, a thiamine auxotroph that gave high yields of alpha-KG from glycerol, was obtained by screening for ampicillin/kanamycin resistance and thiamine auxotrophy. The strain was identified as Yarrowia lipolytica based on physiological, chemical, and phylogenetic analysis. The ability of the strain to convert glycerol to alpha-KG was analysed by investigating the effects of nutritional factors, including thiamine, riboflavin, nitrogen sources, and calcium ion. Thiamine and calcium ion concentration had the greatest effect on alpha-KG accumulation. Under optimal conditions, a yield of 39.2 g l(-1)alpha-KG was obtained from 100 g l(-1) glycerol, with 16.84 g l(-1) pyruvate as a by-product. The current work provides a method for screening for an alpha-KG overproducer. Nutrients have a significant impact on alpha-KG production in the yeast strain presented here. The alpha-KG-overproducing yeast strain Y. lipolytica WSH-Z06 is a promising parent strain for further metabolic engineering to lower by-product accumulation and accelerate glycerol utilization.
Seiler, Ralph L.
2007-01-01
Ground water is the major source of drinking water in the Carson River Basin, California and Nevada. Previous studies have shown that uranium and gross-alpha radioactivities in ground water can be greater than U.S. Environmental Protection Agency Maximum Contaminant Levels, particularly in the Carson Desert, Churchill County, Nevada. Studies also have shown that the primary source of the gross-alpha radioactivity and alpha-emitting radionuclides in ground water is the dissolution of uranium-rich granitic rocks and basin-fill sediments that have their origins in the Sierra Nevada. However, ground water sampled from some wells in the Carson Desert had gross-alpha radioactivities greater than could be accounted for by the decay of dissolved uranium. The occurrence of polonium-210 (Po-210) was hypothesized to explain the higher than expected gross-alpha radioactivities. This report documents and describes the study design, field and analytical methods, and data used to determine whether Po-210 is the source of excess gross-alpha radioactivity in ground water underlying the Carson Desert in and around Fallon, Nevada. Specifically, this report presents: 1) gross alpha and uranium radioactivities for 100 wells sampled from June to September 2001; and 2) pH, dissolved oxygen, specific conductance, and Po-210 radioactivity for 25 wells sampled in April and June 2007. Results of quality-control samples for the 2007 dataset are also presented.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ma, Hongwei; Shen, Jianfeng; Shi, Min
Graphical abstract: . The as-obtained ({alpha}-MnO{sub 2}) nanomaterials could act as an adsorbent to remove Conge red. More significantly, the nanomaterials are nontoxic and environmentally friendly though a biological MTT assay experiment. Plots of the capacity to remove Conge red with time by the commercial and new-prepared {alpha}-MnO{sub 2}. Inset shows absorption of Congo Red with time by new-prepared rod-clusters {alpha}-MnO{sub 2} (0, 10, 20, 40 and 60 min, respectively). Highlights: {yields} Nanostructured {alpha}-MnO{sub 2} was prepared through a template-free hydrothermal method. {yields} The obtained {alpha}-MnO{sub 2} could act as effective adsorbents to remove organic dyes. {yields} The obtained adsorbentsmore » are environmentally friendly. -- Abstract: In this paper, nanostructured MnO{sub 2} materials were successfully prepared through a simple and template-free hydrothermal method. X-ray diffraction pattern indicates that the as-prepared nanomaterials are {alpha}-MnO{sub 2}. Transmission Electron Microscopy and Scanning Electron Microscopy images demonstrate that nanostructured rod-clusters {alpha}-MnO{sub 2} could be evolved from the nanorods. Brunauer-Emmett-Teller (BET) surface area measurement was employed to characterize the surface property. Moreover, the as-obtained ({alpha}-MnO{sub 2}) nanomaterials could act as an efficient adsorbent to remove Congo Red and Methlylene Blue. More significantly, the nanomaterials are nontoxic and environmentally friendly via biological methylthiazolyldiphenyltetrazoliumbromide assay experiments. Its nontoxic and enhanced adsorbability properties guarantee their safe applications in environmental protection and industrial aspects.« less
ERIC Educational Resources Information Center
Zhang, Zhiyong; Yuan, Ke-Hai
2016-01-01
Cronbach's coefficient alpha is a widely used reliability measure in social, behavioral, and education sciences. It is reported in nearly every study that involves measuring a construct through multiple items. With non-tau-equivalent items, McDonald's omega has been used as a popular alternative to alpha in the literature. Traditional estimation…
ERIC Educational Resources Information Center
Zhang, Zhiyong; Yuan, Ke-Hai
2016-01-01
Cronbach's coefficient alpha is a widely used reliability measure in social, behavioral, and education sciences. It is reported in nearly every study that involves measuring a construct through multiple items. With non-tau-equivalent items, McDonald's omega has been used as a popular alternative to alpha in the literature. Traditional estimation…
neutrons to thermal energies. US 2,573,069 METHOD AND APPARATUS FOR MEASURING STRONG ALPHA EMITTERS - Segrà ¨, E. G.; October 30, 1951 (to the U.S. Atomic Energy Commission) This patent describes an apparatus and method for the determination of the strength of a strong alpha emitter. The apparatus is so
ERIC Educational Resources Information Center
Raykov, Tenko; Marcoulides, George A.
2015-01-01
A direct approach to point and interval estimation of Cronbach's coefficient alpha for multiple component measuring instruments is outlined. The procedure is based on a latent variable modeling application with widely circulated software. As a by-product, using sample data the method permits ascertaining whether the population discrepancy…
Alpha Training: A Technique for Changing Behavior in Children and Adults.
ERIC Educational Resources Information Center
Matthews, Doris B.
Several counseling methods have attempted to help individuals change their behavior patterns. Techniques that teach control of the internal functions of the mind, body, and emotions are designed to allow the individual to reach his/her potential. Alpha training is one such method that is concerned with a brain wave pattern yielding an alert,…
Improving Alpha Spectrometry Energy Resolution by Ion Implantation with ICP-MS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dion, Michael P.; Liezers, Martin; Farmer, Orville T.
2015-01-01
We report results of a novel technique using an Inductively Coupled Plasma Mass Spectrometer (ICP-MS) as a method of source preparation for alpha spectrometry. This method produced thin, contaminant free 241Am samples which yielded extraordinary energy resolution which appear to be at the lower limit of the detection technology used in this research.
FcepsilonRI-alpha siRNA inhibits the antigen-induced activation of mast cells.
Safaralizadeh, Reza; Soheili, Zahra-Soheila; Deezagi, Abdolkhaleg; Pourpak, Zahra; Samiei, Shahram; Moin, Mostafa
2009-12-01
FcepsilonRI, The high affinity receptor for IgE plays a critical role in triggering the allergic reactions. It is responsible for inducing mast cell degranulation and deliberation of allergy mediators when it is aggregated by allergen and IgE complexes. FcepsilonRI on the mast cells consists of three subunits; alpha chain directly binds IgE, beta chain and dimmer of gamma chains together mediate intracellular signaling. Cross-linking of IgE-bound FcepsilonRI on the surface of mast cells and basophils by the multivalent antigen induces release of chemical mediators. The present in vitro study was designed to investigate the effect of synthetic FcepsilonRI-alpha siRNA on the antigen-induced activation of MC/9 cells. MC/9 cells which are murine mast cells were transfected by FcepsilonRI-alpha siRNA and negative control siRNA. After 6 h, anti-DNP (Dinitrophenyl) IgE was used for the cells sensitization. Then the cells were challenged with Dinitrophenyl-Human Serum Albumin (DNP-HSA) for mast cell degranulation induction before collection of supernatants. The amount of mRNA and protein expression was measured by Real Time PCR and western blot analysis, respectively. Determination of the expression rate of FcepsilonRI-alpha on cell surface was achieved by flow cytometry. ELISA and spectrophotometry methods were used subsequently for measuring the effects of FcepsilonRI-alpha siRNA on antigen-induced histamine and beta-hexosaminidase release. FcepsilonRI-alpha siRNA treated cells showed significant decrease in FcepsilonRI-alpha mRNA and protein expression in comparison to control cells. FcepsilonRI-mediated mast cell release of beta-hexosaminidase and histamine were also inhibited. In this study it was shown that FcepsilonRI-alpha siRNA could suppress FcepsilonRI-alpha expression and inhibited degranulation and histamine release in antigen-stimulated MC/9 cells. In conclusion, knock-down of FcepsilonRI-alpha by siRNA could be a promising method for inhibition of the mast cell-mediated allergic reactions.
Indo, Y; Glassberg, R; Yokota, I; Tanaka, K
1991-01-01
In our previous study of eight glutaric acidemia type II (GAII) fibroblast lines by using [35S]methionine labeling and immunoprecipitation, three of them had a defect in the synthesis of the alpha-subunit of electron transfer flavoprotein (alpha-ETF) (Ikeda et al. 1986). In one of them (YH1313) the labeling of the mature alpha-ETF was barely detectable, while that of the precursor (p) was stronger. In another (YH605) no synthesis of immunoreactive p alpha-ETF was detectable. In the third cell line (YH1391) the rate of variant p alpha-ETF synthesis was comparable to normal, but its electrophoretic mobility was slightly faster than normal. In the present study, the northern blot analysis revealed that all three mutant cell lines contained p alpha-ETF mRNA and that their size and amount were comparable to normal. In immunoblot analysis, both alpha- and beta-ETF bands were barely detectable in YH1313 and YH605 but were detectable in YH1391 in amounts comparable to normal. Sequencing of YH1313 p alpha-ETF cDNA via PCR identified a transversion of T-470 to G. We then devised a simple PCR method for the 119-bp section (T-443/G-561) for detecting this mutation. In the upstream primer, A-466 was artificially replaced with C, to introduce a BstNI site into the amplified copies in the presence of G-470 from the variant sequence. The genomic DNA analysis using this method demonstrated that YH1313 was homozygous for T----G-470 transversion. It was not detected either in two other alpha-ETF-deficient GAII or in seven control cell lines. The alpha-ETF cDNA sequence in YH605 was identical to normal. Images Figure 1 Figure 2 Figure 3 Figure 5 PMID:1882842
Shi, YingWu; Zhang, Xuebing; Lou, Kai
2013-01-01
Endophytic microorganisms reside within plant tissues and have often been found to promote plant growth. In this study, endophytic microorganisms were isolated from the roots, stems, leaves, and seeds of healthy drunken horse grass, Achnatherum inebrians (Hance) Keng (Poales: Poaceae), through the use of a grinding separation method and identified by a dual approach of morphological and physiological observation and 16S rRNA gene-based (for bacteria) and internal transcribed sequence-based (for fungi) molecular identification. The endophytes were then inoculated into liquid media for fermentation, and their crude extracts were employed for insecticidal activity tests using slide disc immersion and nebulization methods. A total of 89 bacteria species, which were classified into eight genera, Bacillus, Pseudomonas, Actinomyces, Corynebacterium, Acinetobacter, Sphingomonas, Paenibacillus, and Phyllobacterium, and two fungi, Claviceps and Chaetomium, were isolated. Of these species, isolates Streptomyces albus (Rossi-Doria) Waksman and Henrici (Actinomycetales: Streptomycetaceae) (GA) and Claviceps purpurea (Fr.) Tul. (Hypocreales: Clavicipitaceae) (PF-2) were shown to produce mortality rates of more than 90% in the cotton aphid, Aphis gossypii Glover (Hemiptera: Aphididae), after first and second screenings. The isolates PF-2 and GA associated with A. inebrians had significant insecticidal activities towards A. gossypii Glover (Hemiptera: Aphididae) and may provide a new biological resource for exploring a new microbial insecticide. PMID:24784492
DOE Office of Scientific and Technical Information (OSTI.GOV)
Talamo, Alberto; Gohar, Yousry
2016-06-01
This report describes different methodologies to calculate the effective neutron multiplication factor of subcritical assemblies by processing the neutron detector signals using MATLAB scripts. The subcritical assembly can be driven either by a spontaneous fission neutron source (e.g. californium) or by a neutron source generated from the interactions of accelerated particles with target materials. In the latter case, when the particle accelerator operates in a pulsed mode, the signals are typically stored into two files. One file contains the time when neutron reactions occur and the other contains the times when the neutron pulses start. In both files, the timemore » is given by an integer representing the number of time bins since the start of the counting. These signal files are used to construct the neutron count distribution from a single neutron pulse. The built-in functions of MATLAB are used to calculate the effective neutron multiplication factor through the application of the prompt decay fitting or the area method to the neutron count distribution. If the subcritical assembly is driven by a spontaneous fission neutron source, then the effective multiplication factor can be evaluated either using the prompt neutron decay constant obtained from Rossi or Feynman distributions or the Modified Source Multiplication (MSM) method.« less
Amphipathic Alpha-Helical Peptide Compositions as Antiviral Agents
NASA Technical Reports Server (NTRS)
Frank, Curtis W. (Inventor); Cheong, Kwang Ho (Inventor); Glenn, Jeffrey (Inventor); Cho, Nam-Joon (Inventor)
2014-01-01
The invention features methods and compositions that exploit the ability of amphipathic alpha-helical (AH) peptides to cause disruption of lipid-containing vesicles, such as enveloped viruses, in a size-dependent manner.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, Young Sun; Beers, Timothy C.; Prieto, Carlos Allende
We present a method for the determination of [{alpha}/Fe] ratios from low-resolution (R = 2000) SDSS/SEGUE stellar spectra. By means of a star-by-star comparison with degraded spectra from the ELODIE spectral library and with a set of moderately high-resolution (R = 15, 000) and medium-resolution (R = 6000) spectra of SDSS/SEGUE stars, we demonstrate that we are able to measure [{alpha}/Fe] from SDSS/SEGUE spectra (with S/N>20/1) to a precision of better than 0.1 dex, for stars with atmospheric parameters in the range T{sub eff} = [4500, 7000] K, log g = [1.5, 5.0], and [Fe/H] = [-1.4, +0.3], over themore » range [{alpha}/Fe] = [-0.1, +0.6]. For stars with [Fe/H] <-1.4, our method requires spectra with slightly higher signal-to-noise to achieve this precision (S/N>25/1). Over the full temperature range considered, the lowest metallicity star for which a confident estimate of [{alpha}/Fe] can be obtained from our approach is [Fe/H] {approx}-2.5; preliminary tests indicate that a metallicity limit as low as [Fe/H] {approx}-3.0 may apply to cooler stars. As a further validation of this approach, weighted averages of [{alpha}/Fe] obtained for SEGUE spectra of likely member stars of Galactic globular clusters (M15, M13, and M71) and open clusters (NGC 2420, M67, and NGC 6791) exhibit good agreement with the values of [{alpha}/Fe] from previous studies. The results of the comparison with NGC 6791 imply that the metallicity range for the method may extend to {approx}+0.5.« less
Ahonen, Emily Q; Watson, Dennis P; Adams, Erin L; McGuire, Alan
2017-01-01
Detailed descriptions of implementation strategies are lacking, and there is a corresponding dearth of information regarding methods employed in implementation strategy development. This paper describes methods and findings related to the alpha testing of eLearning modules developed as part of the Housing First Technical Assistance and Training (HFTAT) program's development. Alpha testing is an approach for improving the quality of a product prior to beta (i.e., real world) testing with potential applications for intervention development. Ten participants in two cities tested the modules. We collected data through (1) a structured log where participants were asked to record their experiences as they worked through the modules; (2) a brief online questionnaire delivered at the end of each module; and (3) focus groups. The alpha test provided useful data related to the acceptability and feasibility of eLearning as an implementation strategy, as well as identifying a number of technical issues and bugs. Each of the qualitative methods used provided unique and valuable information. In particular, logs were the most useful for identifying technical issues, and focus groups provided high quality data regarding how the intervention could best be used as an implementation strategy. Alpha testing was a valuable step in intervention development, providing us an understanding of issues that would have been more difficult to address at a later stage of the study. As a result, we were able to improve the modules prior to pilot testing of the entire HFTAT. Researchers wishing to alpha test interventions prior to piloting should balance the unique benefits of different data collection approaches with the need to minimize burdens for themselves and participants.
Crans, Gerald G; Shuster, Jonathan J
2008-08-15
The debate as to which statistical methodology is most appropriate for the analysis of the two-sample comparative binomial trial has persisted for decades. Practitioners who favor the conditional methods of Fisher, Fisher's exact test (FET), claim that only experimental outcomes containing the same amount of information should be considered when performing analyses. Hence, the total number of successes should be fixed at its observed level in hypothetical repetitions of the experiment. Using conditional methods in clinical settings can pose interpretation difficulties, since results are derived using conditional sample spaces rather than the set of all possible outcomes. Perhaps more importantly from a clinical trial design perspective, this test can be too conservative, resulting in greater resource requirements and more subjects exposed to an experimental treatment. The actual significance level attained by FET (the size of the test) has not been reported in the statistical literature. Berger (J. R. Statist. Soc. D (The Statistician) 2001; 50:79-85) proposed assessing the conservativeness of conditional methods using p-value confidence intervals. In this paper we develop a numerical algorithm that calculates the size of FET for sample sizes, n, up to 125 per group at the two-sided significance level, alpha = 0.05. Additionally, this numerical method is used to define new significance levels alpha(*) = alpha+epsilon, where epsilon is a small positive number, for each n, such that the size of the test is as close as possible to the pre-specified alpha (0.05 for the current work) without exceeding it. Lastly, a sample size and power calculation example are presented, which demonstrates the statistical advantages of implementing the adjustment to FET (using alpha(*) instead of alpha) in the two-sample comparative binomial trial. 2008 John Wiley & Sons, Ltd
Maragou, Niki C; Rosenberg, Erwin; Thomaidis, Nikolaos S; Koupparis, Michael A
2008-08-15
A novel LC-ESI-MS method for the simultaneous determination of four of the most significant estrogenic compounds naturally occurring in beer, 8-prenylnaringenin (8-PN), zearalenone (ZON), alpha-zearalenol (alpha-ZOL) and beta-zearalenol (beta-ZOL) which requires minimal sample preparation was developed using a chemometric approach. Experimental design was applied to assess the effects of the LC-ESI-MS parameters (mobile phase flow rate, drying gas flow, nebuliser pressure and capillary potential) on the obtained signal and to optimize the values in order to provide maximum sensitivity and detectability. The proposed method is simple, consisting only of degassing the beer and diluting with water (1:1, v/v) before injection. Comparison between the two internal standards used, zearalanone (ZAN) and 4,2'-dihydroxychalcone (4,2'-DHC), showed that ZAN performs better as internal standard not only for the mycotoxins but for 8-PN as well, giving lower % RSDs. Under inter-day conditions mean recoveries were 107% for ZON, 87.8% for alpha-ZOL, 72.8% for beta-ZOL, and 77.5% for 8-PN. The corresponding % RSDs ranged between 5.0 and 8.0. The method limits of detection were 1.3, 1.4, 1.0 and 0.8 ng mL(-1) for ZON, alpha-ZOL, beta-ZOL and 8-PN, respectively. The method was applied to 15 beer samples obtained from local supermarkets and the concentration of the phytoestrogen 8-PN in beer ranged between <0.8 and 38.6 ng mL(-1), while neither ZON nor its metabolites, alpha-ZOL and beta-ZOL, were detected.
Polarimetry of the HI Lyman-alpha for coronal magnetic field diagnostics
NASA Technical Reports Server (NTRS)
Fineschi, Silvano; Hoover, Richard B.; Zukic, Muamer; Kim, Jongmin; Walker, Arthur B. C., Jr.; Baker, Phillip, C.
1993-01-01
We discuss and analyze the possible sources of observational and instrumental uncertainty that can be encountered in measuring magnetic fields of the solar corona through polarimetric observations of the Hanle effect of the coronal Ly-alpha line. The Hanle effect is the modification of the linear polarization of a resonantly scattered line, due to the presence of a magnetic field. Simulated observations are used to examine how polarimetric measurements of this effect are affected by the line-of-sight integration, the electron collisions, and the Ly-alpha geocorona. We plan to implement the coronal magnetic field diagnostics via the Ly-alpha Hanle effect using an all-reflecting Ly-alpha coronagraph/polarimeter (Ly-alphaCoPo) which employs reflecting multilayer mirrors, polarizers, and filters. We discuss here the requirements for such an instrument, and analyze the sources of instrumental uncertainty for polarimetric observations of the coronal Ly-alpha Hanle effect. We conclude that the anticipated polarization signal from the corona and the expected performance of the Ly-alphaCoPo instrument are such that the Ly-alpha Hanle effect method for coronal field diagnostics is feasible.
Fluorescent nuclear track detectors for alpha radiation microdosimetry.
Kouwenberg, J J M; Wolterbeek, H T; Denkova, A G; Bos, A J J
2018-06-07
While alpha microdosimetry dates back a couple of decades, the effects of localized energy deposition of alpha particles are often still unclear since few comparative studies have been performed. Most modern alpha microdosimetry studies rely for large parts on simulations, which negatively impacts both the simplicity of the calculations and the reliability of the results. A novel microdosimetry method based on the Fluorescent Nuclear Track Detector, a versatile tool that can measure individual alpha particles at sub-micron resolution, yielding accurate energy, fluence and dose rate measurements, was introduced to address these issues. Both the detectors and U87 glioblastoma cell cultures were irradiated using an external Am241 alpha source. The alpha particle tracks measured with a Fluorescent Nuclear Track Detector were used together with high resolution 3D cell geometries images to calculate the nucleus dose distribution in the U87 glioblastoma cells. The experimentally obtained microdosimetry parameters were thereafter applied to simulations of 3D U87 cells cultures (spheroids) with various spatial distributions of isotopes to evaluate the effect of the nucleus dose distribution on the expected cell survival. The new experimental method showed good agreement with the analytically derived nucleus dose distributions. Small differences (< 5%) in the relative effectiveness were found for isotopes in the cytoplasm and on the cell membrane versus external irradiation, while isotopes located in the nucleus or on the nuclear membrane showed a substantial increase in relative effectiveness (33 - 51%). The ease-of-use, good accuracy and use of experimentally derived characteristics of the radiation field make this method superior to conventional simulation-based microdosimetry studies. Considering the uncertainties found in alpha radionuclide carriers in-vivo and in-vitro, together with the large contributions from the relative biological effectiveness and the oxygen enhancement ratio, it is expected that only carriers penetrating or surrounding the cell nucleus will substantially benefit from microdosimetry.
An overview of targeted alpha therapy with 225Actinium and 213Bismuth.
Morgenstern, Alfred; Apostolidis, Christos; Kratochwil, Clemens; Sathekge, Mike; Krolicki, Leszek; Bruchertseifer, Frank
2018-05-01
Recent reports of the remarkable therapeutic efficacy of 225Ac-labeled PSMA-617 for therapy of metastatic castration-resistant prostate cancer have underlined the clinical potential of targeted alpha therapy. This review describes methods for the production of 225Ac and its daughter nuclide 213Bi and summarizes the current clinical experience with both alpha emitters with particular focus on recent studies of targeted alpha therapy of bladder cancer, brain tumors, neuroendocrine tumors and prostate cancer. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
A history of nuclear transmutations by natural alpha particles
NASA Astrophysics Data System (ADS)
Leone, Matteo
2005-11-01
A systematic account of the use of alpha particles up to the 1930s for promoting the disintegration of atoms is here provided. As will be shown, a number of different radium family alpha sources were used in the experiments that led to the discoveries of the proton (Rutherford E 1919 Phil. Mag. 37 581-7) and neutron (Chadwick J 1932 Nature 129 312). The reasons leading to the employment of a particular alpha particle source, as well as the relationship between these sources and the available methods of recording, will be closely addressed.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Haslam, J J; Wall, M A; Johnson, D L
We have measured and modeled the change in electrical resistivity due to partial transformation to the martensitic {alpha}{prime}-phase in a {delta}-phase Pu-Ga matrix. The primary objective is to relate the change in resistance, measured with a 4-probe technique during the transformation, to the volume fraction of the {alpha}{prime} phase created in the microstructure. Analysis by finite element methods suggests that considerable differences in the resistivity may be anticipated depending on the orientational and morphological configurations of the {alpha}{prime} particles. Finite element analysis of the computed resistance of an assembly of lenticular shaped particles indicates that series resistor or parallel resistormore » approximations are inaccurate and can lead to an underestimation of the predicted amount of {alpha}{prime} in the sample by 15% or more. Comparison of the resistivity of a simulated network of partially transformed grains or portions of grains suggests that a correction to the measured resistivity allows quantification of the amount of {alpha}{prime} phase in the microstructure with minimal consideration of how the {alpha}{prime} morphology may evolve. It is found that the average of the series and parallel resistor approximations provide the most accurate relationship between the measured resistivity and the amount of {alpha}{prime} phase. The methods described here are applicable to any evolving two-phase microstructure in which the resistance difference between the two phases is measurable.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Aushev, A A; Barinov, S P; Vasin, M G
2015-06-30
We present the results of employing the alpha-spectrometry method to determine the characteristics of porous materials used in targets for laser plasma experiments. It is shown that the energy spectrum of alpha-particles, after their passage through porous samples, allows one to determine the distribution of their path length in the foam skeleton. We describe the procedure of deriving such a distribution, excluding both the distribution broadening due to statistical nature of the alpha-particle interaction with an atomic structure (straggling) and hardware effects. The fractal analysis of micro-images is applied to the same porous surface samples that have been studied bymore » alpha-spectrometry. The fractal dimension and size distribution of the number of the foam skeleton grains are obtained. Using the data obtained, a distribution of the total foam skeleton thickness along a chosen direction is constructed. It roughly coincides with the path length distribution of alpha-particles within a range of larger path lengths. It is concluded that the combined use of the alpha-spectrometry method and fractal analysis of images will make it possible to determine the size distribution of foam skeleton grains (or pores). The results can be used as initial data in theoretical studies on propagation of the laser and X-ray radiation in specific porous samples. (laser plasma)« less
Gray, Rachael; Canfield, Paul; Rogers, Tracey
2005-09-01
Blood protein analysis including total serum protein and albumin by chemical methods, fibrinogen estimation and serum protein electrophoresis (SPE) was performed on the leopard seal, Hydrurga leptonyx. The most commonly observed SPE pattern was eight fractions designated albumin, alpha(1a), alpha(1b), alpha(2a), alpha(2b), beta(1), beta(2) and gamma-globulin. Significantly higher total serum protein and albumin concentrations, as determined by chemical methods, and significantly higher alpha(2)-globulin concentrations, determined by SPE, were seen in free-ranging male seals compared to females, whilst significantly higher beta-globulin concentrations were seen in female seals. Season of sampling influenced fibrinogen and beta(2)-globulin concentrations, whereas there were no significant differences in any protein concentrations with moult status. Qualitative comparison of SPE traces of leopard seals in Antarctica with "sick" individuals in NSW, Australia revealed obvious differences, as did quantitative comparison of protein concentrations where differences in alpha(1), alpha(2), beta(1), beta(2), and gamma-globulin concentrations were seen. These findings suggest that SPE is a useful tool for investigating serum proteins in the leopard seal, with applications for the investigation of "sick" individuals and the assessment of variation in homeostasis. This technique could also be used to identify the presence of environmental stressors, subclinical disease and physiological variation within specific seal populations.
NMR solution structure of the mitochondrial F1beta presequence from Nicotiana plumbaginifolia.
Moberg, Per; Nilsson, Stefan; Ståhl, Annelie; Eriksson, Anna-Carin; Glaser, Elzbieta; Mäler, Lena
2004-03-05
We have isolated, characterized and determined the three-dimensional NMR solution structure of the presequence of ATPsynthase F1beta subunit from Nicotiana plumbaginifolia. A general method for purification of presequences is presented. The method is based on overexpression of a mutant precursor containing a methionine residue introduced at the processing site, followed by CNBr-cleavage and purification of the presequence on a cation-exchange column. The F1beta presequence, 53 amino acid residues long, retained its native properties as evidenced by inhibition of in vitro mitochondrial import and processing at micromolar concentrations. CD spectroscopy revealed that the F1beta presequence formed an alpha-helical structure in membrane mimetic environments such as SDS and DPC micelles (approximately 50% alpha-helix), and in acidic phospholipid bicelles (approximately 60% alpha-helix). The NMR solution structure of the F1beta presequence in SDS micelles was determined on the basis of 518 distance and 21 torsion angle constraints. The structure was found to contain two helices, an N-terminal amphipathic alpha-helix (residues 4-15) and a C-terminal alpha-helix (residues 43-53), separated by a largely unstructured 27 residue long internal domain. The N-terminal amphipathic alpha-helix forms the putative Tom20 receptor binding site, whereas the C-terminal alpha-helix is located upstream of the mitochondrial processing peptidase cleavage site.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Siman, W; Kappadath, S
2014-06-01
Purpose: Some common methods to solve for deadtime are (1) dual-source method, which assumes two equal activities; (2) model fitting, which requires multiple acquisitions as source decays; and (3) lossless model, which assumes no deadtime loss at low count rates. We propose a new analytic alternative solution to calculate deadtime for paralyzable gamma camera. Methods: Deadtime T can be calculated analytically from two distinct observed count rates M1 and M2 when the ratio of the true count rates alpha=N2/N1 is known. Alpha can be measured as a ratio of two measured activities using dose calibrators or via radioactive decay. Knowledgemore » of alpha creates a system with 2 equations and 2 unknowns, i.e., T and N1. To verify the validity of the proposed method, projections of a non-uniform phantom (4GBq 99mTc) were acquired in using Siemens SymbiaS multiple times over 48 hours. Each projection has >100kcts. The deadtime for each projection was calculated by fitting the data to a paralyzable model and also by using the proposed 2-acquisition method. The two estimates of deadtime were compared using the Bland-Altmann method. In addition, the dependency of uncertainty in T on uncertainty in alpha was investigated for several imaging conditions. Results: The results strongly suggest that the 2-acquisition method is equivalent to the fitting method. The Bland-Altman analysis yielded mean difference in deadtime estimate of ∼0.076us (95%CI: -0.049us, 0.103us) between the 2-acquisition and model fitting methods. The 95% limits of agreement were calculated to be -0.104 to 0.256us. The uncertainty in deadtime calculated using the proposed method is highly dependent on the uncertainty in the ratio alpha. Conclusion: The 2-acquisition method was found to be equivalent to the parameter fitting method. The proposed method offers a simpler and more practical way to analytically solve for a paralyzable detector deadtime, especially during physics testing.« less
Persianinov, L S; Chernukha, E A
1975-01-01
The authors had performed comperative studies of the effect of the induction of abortion in late pregnancy according to the medical indications by intra-amniotic injection of 20% hypertonic NaCl saline in 26 pregnant patients, of 25 mg prostaglandin F2alpha with 6 hours' intervals in 25 patients, a single dose injection of 40 mg PGF2alpha in 27 cases and single dose injection of 2,5 mg 15-me-PGF2alpha given to 25 patients. The highest success rate was obtained with the single dose injection of 2,5 mg 15-me-PGF2alpha and the lowest success rate was obtained with 25 mg prostaglandin F2alpha with 6 hours' intervals. Despite of rather high procentage of success rate in using the hypertonic NaCl saline, this method is more dangerous in the moment of the injection of saline and complications during the abortion (water intoxication, necrosis of tissue, coagulation defects and other). The most frequently incountered side-effects in using PGs were vomiting and diarhea. Histologic examinations of the placenta revealed massive bleedings, at frequency rate being the same for prostaglandins and the hypertonic saline. The degree of isoimmunisation was lower with prostaglandins than with hypertonic NaCl saline, despite of the late dates of pregnancy termination. The intro-amniotic injection of the small volume solution of 15-me-PGF2alpha or PGF2alpha is more simpler and easier from the technical point of view than any methodic recommended for using saline and at the same time it is more effective.
Hirata, Keiko; Shimamura, Yasuhiro; Suzuki, Keiko; Sadamasu, Yuki; Ito, Koichi
2005-12-01
We have developed an analytical method for components of alpha-glucosyltransferase-treated stevia, a food additive product. Suitable conditions to separate additional sugar from alpha-glucosyltransferase-treated stevia by using glucoamylase were found (55 degrees C for 3 hr with 250 U of glucoamylase in 10 mL of reaction solution). By solid-phase extraction using a C18 cartridge column, polysaccharides were excluded from the sample, and the glycosides and sugar obtained after hydrolysis with glucoamylase were separated on another C18 cartridge column. The glycosides and sugar contents were determined by HPLC. By this method, additional sugar was detected in all of three product samples tested and the sugar was glucose. The contents of glucose and total glycosides (minus unreacted glycoside) were 25-42% and 35.7-52.5%, respectively. In alpha-glucosyltransferase-treated stevia, the sum of total glycosides and glucose amounted to 77.5-80.4% of the total and their recoveries from samples from which polysaccharide had been excluded by C18 cartridge column processing were over 85%. The contents of alpha-glucosyltransferase-treated stevia obtained by multiplying the sugar content by the coefficient (0.9) for hydrolysis and converting on dry weight basis were all over 80.0% and met the standard set by the Japan Food Additives Association.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Takahashi, Hiromitsu; Sakurai, Soki; Makishima, Kazuo, E-mail: hirotaka@hep01.hepl.hiroshima-u.ac.jp
To investigate the physics of mass accretion onto weakly magnetized neutron stars (NSs), 95 archival Rossi X-Ray Timing Explorer data sets of an atoll source 4U 1608-522, acquired over 1996-2004 in the so-called upper-banana state, were analyzed. The object meantime exhibited 3-30 keV luminosity in the range of {approx}< 10{sup 35}-4 x 10{sup 37} erg s{sup -1}, assuming a distance of 3.6 kpc. The 3-30 keV Proportional Counter Array spectra, produced one from each data set, were represented successfully with a combination of a soft and a hard component, the presence of which was revealed in a model-independent manner bymore » studying spectral variations among the observations. The soft component is expressed by the so-called multi-color disk model with a temperature of {approx}1.8 keV, and is attributed to the emission from an optically thick standard accretion disk. The hard component is a blackbody (BB) emission with a temperature of {approx}2.7 keV, thought to be emitted from the NS surface. As the total luminosity increases, a continuous decrease is observed in the ratio of the BB luminosity to that of the disk component. This property suggests that it gradually becomes difficult for the matter flowing through the accretion disk to reach the NS surface, presumably forming outflows driven by the increased radiation pressure. On timescales of hours to days, the overall source variability was found to be controlled by two independent variables: the mass accretion rate and the innermost disk radius, which changes both physically and artificially.« less
THE LIGHT CURVE OF HERCULES X-1 AS OBSERVED BY THE ROSSI X-RAY TIMING EXPLORER
DOE Office of Scientific and Technical Information (OSTI.GOV)
Leahy, D. A.; Igna, Ciprian, E-mail: leahy@ucalgary.ca
2011-07-20
Analysis of the light curve of Hercules X-1 using the full set of archival observations of Hercules X-1 by the Rossi X-Ray Timing Explorer/Proportional Counter Array (RXTE/PCA) is reported. The observations cover time periods that Her X-1 is in main high, short high, and low states, and an anomalous low state (ALS). They include over 1.4 Ms of net exposure time. We present 35 day and orbital phase folded light curves of the count rates and softness ratios, showing the range of behaviors of Her X-1 with the high sensitivity of the RXTE/PCA. New phenomena are uncovered and previous phenomenamore » are seen in greater detail. For both main high and short high states, the fraction of time in dips is found to be a function of orbital phase and of 35 day phase. It increases steadily with orbital phase past orbital phase 0.3 and is higher at the start and end of both main high and short high states. It is higher for short high state (62%) than for main high state (28%). The normal low state data and ALS data are compared: the low state count rate is {approx}twice as high as for ALS data. The 2-4 keV to 9-20 keV softness ratio changes smoothly with orbital phase for low states and ALSs, and is indistinguishable between the two, yet very different than for the high states. This supports models for which the cause of the ALS is changed disk geometry that prevents a direct line of sight from neutron star to observer at all 35 day phases.« less
NASA Astrophysics Data System (ADS)
Maselli, A.; Capitanio, F.; Feroci, M.; Massa, F.; Massaro, E.; Mineo, T.
2018-04-01
We investigate some key aspects of the "heartbeat" variability consisting of series of bursts with a slow rise and a fast decay, thus far detected only in GRS 1915+105, IGR J17091-3624, and MXB 1730-335. A previous analysis based on BeppoSAX data of GRS 1915+105 revealed a hard-X delay (HXD), that is a lag of the burst rise at higher energies with respect to lower ones; this leads to narrower pulse widths, w, at higher energies. We here use some light curves of Rossi-XTE observations of GRS 1915+105 for a deeper analysis of this effect and search for its presence in those extracted from some IGR J17091-3624 and MXB 1730-335 observations performed with the same satellite. Our results show that, at variance with GRS 1915+105, no HXD is evident in the light curves of MXB 1730-335 and only a marginal HXD may be argued for IGR J17091-3624. For GRS 1915+105 we find a decreasing trend of the pulse width with energy following a power law w = A ṡ E-s with an index s ≈ 0.8. Furthermore, we confirm the increase of the HXD with the recurrence time Trec of the bursts in each series that was already found in previous works using BeppoSAX data. Based on a spectral analysis of these three sources we conclude that the differences highlighted in the properties of the "heartbeat" variability are probably related to the different accreting compact object and the eventual presence of a corona in these binary interacting systems.
Role of constant value of surface diffuseness in alpha decay half-lives of superheavy nuclei
NASA Astrophysics Data System (ADS)
Dehghani, V.; Alavi, S. A.; Benam, Kh.
2018-05-01
By using WKB method and considering deformed Woods-Saxon nuclear potential, deformed Coulomb potential, and centrifugal potential, the alpha decay half-lives of 68 superheavy alpha emitters have been calculated. The effect of the constant value of surface diffuseness parameter in the range of 0.1 ≤ a ≤ 0.9 (fm) on the potential barrier, tunneling probability, assault frequency, and alpha decay half-lives has been investigated. Significant differences were observed for alpha decay half-lives and decay quantities in this range of surface diffuseness. Good agreement between calculated half-lives with fitted surface diffuseness parameter a = 0.54 (fm) and experiment was observed.
Tricarico, J M; Abney, M D; Galyean, M L; Rivera, J D; Hanson, K C; McLeod, K R; Harmon, D L
2007-03-01
Three experiments were conducted to examine the effects of an Aspergillus oryzae extract containing alpha-amylase activity on performance and carcass characteristics of finishing beef cattle. In Exp. 1, 120 crossbred steers were used in a randomized complete block design to evaluate the effects of roughage source (alfalfa hay vs. cottonseed hulls) and supplemental alpha-amylase at 950 dextrinizing units (DU)/kg of DM. Significant roughage source x alpha-amylase interactions (P < 0.05) were observed for performance. In steers fed cottonseed hulls, supplemental alpha-amylase increased ADG through d 28 and 112 and tended (P < 0.15) to increase ADG in all other periods. The increases in ADG were related to increased DMI and efficiency of gain during the initial 28-d period but were primarily related to increased DMI as the feeding period progressed. Supplemental alpha-amylase increased (P = 0.02) the LM area across both roughage sources. In Exp. 2, 96 crossbred heifers were used in a randomized complete block design with a 2 x 3 factorial arrangement of treatments to evaluate the effects of corn processing (dry cracked vs. high moisture) and supplemental alpha-amylase concentration (0, 580, or 1,160 DU/kg of DM). Alpha-amylase supplementation increased DMI (P = 0.05) and ADG (P = 0.03) during the initial 28 d on feed and carcass-adjusted ADG (P = 0.04) across corn processing methods. Longissimus muscle area was greatest (quadratic effect, P = 0.04), and yield grade was least (quadratic effect, P = 0.02) in heifers fed 580 DU of alpha-amylase/kg of DM across corn processing methods. In Exp. 3, 56 crossbred steers were used in a randomized complete block design to evaluate the effects of supplemental alpha-amylase (930 DU/kg of DM) on performance when DMI was restricted to yield a programmed ADG. Alpha-amylase supplementation did not affect performance when DMI was restricted. We conclude that dietary alpha-amylase supplementation of finishing beef diets may result in increased ADG through increased DMI under certain dietary conditions and that further research is warranted to explain its mode of action and interactions with dietary ingredients.
McGrath, J C; Naghadeh, M A; Pediani, J D; Mackenzie, J F; Daly, C J
1999-01-01
alpha-Adrenoceptor blocker drugs are commonly used in the clinical (non-surgical) treatment of BPH. alpha1-adrenoceptors were originally sub-divided using agonists but, subsequently, were sub-divided using only antagonists in ligand-ligand interactions, which did not require agonists at all. Ultimately, proof that adrenoceptors are functional receptors for the natural ligands, noradrenaline and adrenaline, requires that agonists be used. The earlier excitement engendered by finding varying agonist potency series in different tissues has not been revisited to place it in the context of current concepts of alpha1-adrenoceptor subtypes. This review will consider the advantages and limitations of different agonists for the study of alpha1-adrenoceptor subtypes including 'extreme' examples where the archetypal alpha1-adrenoceptor agonist phenylephrine activates alpha2-adrenoceptors and others where UK14304, often the alpha2-adrenoceptor agonist of choice, activates alpha1-adrenoceptors. New work will also be presented showing the interaction between agonists and the fluorescent alpha1-adrenoceptor antagonist QAPB. This introduces the novel point of view of studying the displacement of antagonists by agonists. Possible errors in antagonist classification arising from complexity in the actions of agonists and the recently developed method of fluorescent ligand binding on isolated living human prostatic smooth muscle cells will be discussed.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Epstein, N.; Than, K.A. Culp, K.M.
Alpha-thalassemia (alpha-thal) is characterized by the absence or reduction in synthesis of the alpha-globin chain due to either deletions or other abnormalities involving the alpha-globin genes located on the short arm of chromosome 16. The diploid cells have four alpha chain genes. The deletion of one, two, three or all four of these genes could result in mild to a complete alpha chain deficiency known as the Hydrops fetalis syndrome or alpha-thal-1, which causes fetal death. It is important to develop a sensitive test to detect carriers of alpha-thal-1 trait for genetic counseling. It has recently been observed that themore » presence of minute amounts of zeta-globin chains (0.01-1%) could serve as a biological marker of alpha-thal carriers. Because high sensitivity is required, we constructed a monoclonal antibody-based immunoassay which can be analyzed either by colorimetric or fluorimetric methods. By testing blood samples from individuals of Southeast Asian ancestry, we were able to show that various forms and combinations of deletions or inactivations of two or three alpha-globin genes results in alpha-thalassemia conditions that have elevated levels of the zeta-chain. Sensitivity achieved in these tests was < 0.1% zeta chain, or as low as 5 ng zeta-chain. Data correlate with results from reversed phase HPLC.« less
Radon Diffusion Measurement in Polyethylene based on Alpha Detection
NASA Astrophysics Data System (ADS)
Rau, Wolfgang
2011-04-01
We present a method to measure the diffusion of Radon in solid materials based on the alpha decay of the radon daughter products. In contrast to usual diffusion measurements which detect the radon that penetrates a thin barrier, we let the radon diffuse into the material and then measure the alpha decays of the radon daughter products in the material. We applied this method to regular and ultra high molecular weight poly ethylene and find diffusion lengths of order of mm as expected. However, the preliminary analysis shows significant differences between two different approaches we have chosen. These differences may be explained by the different experimental conditions.
Activating STAT3 Alpha for Promoting Healing of Neurons
NASA Technical Reports Server (NTRS)
Conway, Greg
2008-01-01
A method of promoting healing of injured or diseased neurons involves pharmacological activation of the STAT3 alpha protein. Usually, injured or diseased neurons heal incompletely or not at all for two reasons: (1) they are susceptible to apoptosis (cell death); and (2) they fail to engage in axogenesis that is, they fail to re-extend their axons to their original targets (e.g., muscles or other neurons) because of insufficiency of compounds, denoted neurotrophic factors, needed to stimulate such extension. The present method (see figure) of treatment takes advantage of prior research findings to the effect that the STAT3 alpha protein has anti-apoptotic and pro-axogenic properties.
Kennelly, E J; Flynn, T J; Mazzola, E P; Roach, J A; McCloud, T G; Danford, D E; Betz, J M
1999-10-01
The novel alkaloid thalictroidine (1), as well as the known alkaloids taspine (2), magnoflorine (3), anagyrine (4), baptifoline (5), 5,6-dehydro-alpha-isolupanine (6), alpha-isolupanine (7), lupanine (8), N-methylcytisine (9), and sparteine (10), were identified from an extract of Caulophyllum thalictroides rhizomes. N-Methylcytisine exhibited teratogenic activity in the rat embryo culture (REC), an in vitro method to detect potential teratogens. The structure of 1 was elucidated using various spectroscopic methods, primarily by NMR techniques. Thalictroidine, anagyrine, and alpha-isolupanine were not teratogenic in the REC at tested concentrations. Taspine (2) showed high embryotoxicity, but no teratogenic activity, in the REC.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Larbouret, Christel; Robert, Bruno; Linard, Christine
2007-11-15
Purpose: Tumor necrosis factor-{alpha} (TNF-{alpha}) enhances radiotherapy (RT) killing of tumor cells in vitro and in vivo. To overcome systemic side effects, we used a bispecific antibody (BsAb) directed against carcinoembryonic antigen (CEA) and TNF-{alpha} to target this cytokine in a CEA-expressing colon carcinoma. We report the evaluation of this strategy in immunocompetent CEA-transgenic mice. Methods and Materials: The murine CEA-transfected colon carcinoma MC-38 was used for all experiments. In vitro, clonogenic assays were performed after RT alone, TNF-{alpha} alone, and RT plus TNF-{alpha}. In vivo, the mice were randomly assigned to treatment groups: control, TNF-{alpha}, BsAb, BsAb plus TNF-{alpha},more » RT, RT plus TNF-{alpha}, and RT plus BsAb plus TNF-{alpha}. Measurements of endogenous TNF-{alpha} mRNA levels and evaluation of necrosis (histologic evaluation) were assessed per treatment group. Results: In vitro, combined RT plus TNF-{alpha} resulted in a significant decrease in the survival fraction at 2 Gy compared with RT alone (p < 0.00001). In vivo, we observed a complete response in 5 (50%) of 10, 2 (20%) of 10, 2 (18.2%) of 11, and 0 (0%) of 12 treated mice in the RT plus BsAb plus TNF-{alpha}, RT plus TNF-{alpha}, RT alone, and control groups, respectively. This difference was statistically significant when TNF-{alpha} was targeted with the BsAb (p = 0.03). The addition of exogenous TNF-{alpha} to RT significantly increased the endogenous TNF-{alpha} mRNA level, particularly when TNF-{alpha} was targeted with BsAb (p < 0.01). The percentages of necrotic area were significantly augmented in the RT plus BsAb plus TNF-{alpha} group. Conclusion: These results suggest that targeting TNF-{alpha} with the BsAb provokes RT curability in a CEA-expressing digestive tumor syngenic model and could be considered as a solid rationale for clinical trials.« less
Analysis of Decentralized Variable Structure Control for Collective Search by Mobile Robots
DOE Office of Scientific and Technical Information (OSTI.GOV)
Feddema, J.; Goldsmith, S.; Robinett, R.
1998-11-04
This paper presents an analysis of a decentralized coordination strategy for organizing and controlling a team of mobile robots performing collective search. The alpha-beta coordination strategy is a family of collective search algorithms that allow teams of communicating robots to implicitly coordinate their search activities through a division of labor based on self-selected roIes. In an alpha-beta team. alpha agents are motivated to improve their status by exploring new regions of the search space. Beta a~ents are conservative, and reiy on the alpha agents to provide advanced information on favorable regions of the search space. An agent selects its currentmore » role dynamically based on its current status value relative to the current status values of the other team members. Status is determined by some function of the agent's sensor readings, and is generally a measurement of source intensity at the agent's current location. Variations on the decision rules determining alpha and beta behavior produce different versions of the algorithm that lead to different global properties. The alpha-beta strategy is based on a simple finite-state machine that implements a form of Variable Structure Control (VSC). The VSC system changes the dynamics of the collective system by abruptly switching at defined states to alternative control laws . In VSC, Lyapunov's direct method is often used to design control surfaces which guide the system to a given goal. We introduce the alpha-beta aIgorithm and present an analysis of the equilibrium point and the global stability of the alpha-beta algorithm based on Lyapunov's method.« less
Analysis of decentralized variable structure control for collective search by mobile robots
NASA Astrophysics Data System (ADS)
Goldsmith, Steven Y.; Feddema, John T.; Robinett, Rush D., III
1998-10-01
This paper presents an analysis of a decentralized coordination strategy for organizing and controlling a team of mobile robots performing collective search. The alpha- beta coordination strategy is a family of collective search algorithms that allow teams of communicating robots to implicitly coordinate their search activities through a division of labor based on self-selected roles. In an alpha- beta team, alpha agents are motivated to improve their status by exploring new regions of the search space. Beta agents are conservative, and rely on the alpha agents to provide advanced information on favorable regions of the search space. An agent selects its current role dynamically based on its current status value relative to the current status values of the other team members. Status is determined by some function of the agent's sensor readings, and is generally a measurement of source intensity at the agent's current location. Variations on the decision rules determining alpha and beta behavior produce different versions of the algorithm that lead to different global properties. The alpha-beta strategy is based on a simple finite-state machine that implements a form of Variable Structure Control (VSC). The VSC system changes the dynamics of the collective system by abruptly switching at defined states to alternative control laws. In VSC, Lyapunov's direct method is often used to design control surfaces which guide the system to a given goal. We introduce the alpha- beta algorithm and present an analysis of the equilibrium point and the global stability of the alpha-beta algorithm based on Lyapunov's method.
alpha-decay half-lives and Q{sub a}lpha values of superheavy nuclei
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dong Jianmin; Graduate University of Chinese Academy of Sciences, Beijing 100049; School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000
2010-06-15
The alpha-decay half-lives of recently synthesized superheavy nuclei (SHN) are investigated by employing a unified fission model (UFM) where a new method to calculate the assault frequency of alpha emission is used. The excellent agreement with the experimental data indicates the UFM is a useful tool to investigate these alpha decays. It is found that the alpha-decay half-lives become more and more insensitive to the Q{sub a}lpha values as the atomic number increases on the whole, which is favorable for us to predict the half-lives of SHN. In addition, a formula is proposed to compute the Q{sub a}lpha values formore » the nuclei with Z>=92 and N>=140 with a good accuracy, according to which the long-lived SHN should be neutron rich. Several weeks ago, two isotopes of a new element with atomic number Z=117 were synthesized and their alpha-decay chains have been observed. The Q{sub a}lpha formula is found to work well for these nuclei, confirming its predictive power. The experimental half-lives are well reproduced by employing the UFM with the experimental Q{sub a}lpha values. This fact that the experimental half-lives are compatible with experimental Q{sub a}lpha values supports the synthesis of a new element 117 and the experimental measurements to a certain extent.« less
Nakano, Sachie; Tsukimura, Takahiro; Togawa, Tadayasu; Ohashi, Toya; Kobayashi, Masahisa; Takayama, Katsuyoshi; Kobayashi, Yukuharu; Abiko, Hiroshi; Satou, Masatsugu; Nakahata, Tohru; Warnock, David G; Sakuraba, Hitoshi; Shibasaki, Futoshi
2015-01-01
We developed an immunochromatography-based assay for detecting antibodies against recombinant α-galactosidase A proteins in serum. The evaluation of 29 serum samples from Fabry patients, who had received enzyme replacement therapy with agalsidase alpha and/or agalsidase beta, was performed by means of this assay method, and the results clearly revealed that the patients exhibited the same level of antibodies against both agalsidase alpha and agalsidase beta, regardless of the species of recombinant α-galactosidase A used for enzyme replacement therapy. A conventional enzyme-linked immunosorbent assay supported the results. Considering these, enzyme replacement therapy with agalsidase alpha or agalsidase beta would generate antibodies against the common epitopes in both agalsidase alpha and agalsidase beta. Most of the patients who showed immunopositive reaction exhibited classic Fabry phenotype and harbored gene mutations affecting biosynthesis of α-galactosidase A. As immunochromatography is a handy and simple assay system which can be available at bedside, this assay method would be extremely useful for quick evaluation or first screening of serum antibodies against agalsidase alpha or agalsidase beta in Fabry disease with enzyme replacement therapy.
Feasibility of eyes open alpha power training for mental enhancement in elite gymnasts.
Dekker, Marian K J; van den Berg, Berber R; Denissen, Ad J M; Sitskoorn, Margriet M; van Boxtel, Geert J M
2014-01-01
This study focuses on a novel, easy to use and instruction-less method for mental training in athletes. Previous findings suggest that particular mental capacities are needed for achieving peak performance; including attentional control, focus, relaxation and positive affect. Electroencephalography (EEG) alpha brain activity has been associated with neural inhibition during processes of selective attention, for improving efficiency in information processing. Here we hypothesised that eyes open alpha power training by music teaches athletes to (1) learn to self-regulate their brain activity, and (2) learn to increase their baseline alpha power, herewith improving mental capacities such as focusing the allocation of attention. The study was double-blind and placebo-controlled. Twelve elite gymnasts were either given eyes open alpha power training or random beta power training (controls). Results indicate small improvements in sleep quality, mental and physical shape. In our first attempt at getting a grip on mental capacities in athletes, we think this novel training method can be promising. Because gymnastics is one of the most mentally demanding sports, we value even small benefits for the athlete and consider them indicative for future research.
Impact of parental relationships in maximum lod score affected sib-pair method.
Leutenegger, Anne-Louise; Génin, Emmanuelle; Thompson, Elizabeth A; Clerget-Darpoux, Françoise
2002-11-01
Many studies are done in small isolated populations and populations where marriages between relatives are encouraged. In this paper, we point out some problems with applying the maximum lod score (MLS) method (Risch, [1990] Am. J. Hum. Genet. 46:242-253) in these populations where relationships exist between the two parents of the affected sib-pairs. Characterizing the parental relationships by the kinship coefficient between the parents (f), the maternal inbreeding coefficient (alpha(m), and the paternal inbreeding coefficient (alpha(p)), we explored the relationship between the identity by descent (IBD) vector expected under the null hypothesis of no linkage and these quantities. We find that the expected IBD vector is no longer (0.25, 0.5, 0.25) when f, alpha(m), and alpha(p) differ from zero. In addition, the expected IBD vector does not always follow the triangle constraints recommended by Holmans ([1993] Am. J. Hum. Genet. 52:362-374). So the classically used MLS statistic needs to be adapted to the presence of parental relationships. We modified the software GENEHUNTER (Kruglyak et al. [1996] Am. J. Hum. Genet. 58: 1347-1363) to do so. Indeed, the current version of the software does not compute the likelihood properly under the null hypothesis. We studied the adapted statistic by simulating data on three different family structures: (1) parents are double first cousins (f=0.125, alpha(m)=alpha(p)=0), (2) each parent is the offspring of first cousins (f=0, alpha(m)=alpha(p)=0.0625), and (3) parents are related as in the pedigree from Goddard et al. ([1996] Am. J. Hum. Genet. 58:1286-1302) (f=0.109, alpha(m)=alpha(p)=0.0625). The appropriate threshold needs to be derived for each case in order to get the correct type I error. And using the classical statistic in the presence of both parental kinship and parental inbreeding almost always leads to false conclusions. Copyright 2002 Wiley-Liss, Inc.
Modeling individualized coefficient alpha to measure quality of test score data.
Liu, Molei; Hu, Ming; Zhou, Xiao-Hua
2018-05-23
Individualized coefficient alpha is defined. It is item and subject specific and is used to measure the quality of test score data with heterogenicity among the subjects and items. A regression model is developed based on 3 sets of generalized estimating equations. The first set of generalized estimating equation models the expectation of the responses, the second set models the response's variance, and the third set is proposed to estimate the individualized coefficient alpha, defined and used to measure individualized internal consistency of the responses. We also use different techniques to extend our method to handle missing data. Asymptotic property of the estimators is discussed, based on which inference on the coefficient alpha is derived. Performance of our method is evaluated through simulation study and real data analysis. The real data application is from a health literacy study in Hunan province of China. Copyright © 2018 John Wiley & Sons, Ltd.
Analysis of radon and thoron progeny measurements based on air filtration.
Stajic, J M; Nikezic, D
2015-02-01
Measuring of radon and thoron progeny concentrations in air, based on air filtration, was analysed in order to assess the reliability of the method. Changes of radon and thoron progeny activities on the filter during and after air sampling were investigated. Simulation experiments were performed involving realistic measuring parameters. The sensitivity of results (radon and thoron concentrations in air) to the variations of alpha counting in three and five intervals was studied. The concentration of (218)Po showed up to be the most sensitive to these changes, as was expected because of its short half-life. The well-known method for measuring of progeny concentrations based on air filtration is rather unreliable and obtaining unrealistic or incorrect results appears to be quite possible. A simple method for quick estimation of radon potential alpha energy concentration (PAEC), based on measurements of alpha activity in a saturation regime, was proposed. Thoron PAEC can be determined from the saturation activity on the filter, through beta or alpha measurements. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Wang, Jinzhao; Zeng, Su; Wang, Danhua; Hu, Gongyun
2009-05-01
A simple pre-column derivatization-high performance liquid chromatographic (HPLC) method was established for the determination of optical purity of alpha-phenylethylamine. The enantiomers of alpha-phenylethylamine were derivatized with 2,3,4,6-tetra-O-acetyl-beta-D-glucopyranosyl isothiocyanate (GITC). The resulted diastereoisomers were separated on an Agilent Zorbax C18 column (250 mm x 4.6 mm, 5 microm) with a mobile phase of methanol-phosphate buffer (1.36 g/L aqueous solution of potassium dihydrogen phosphate, adjusted to pH 3.0 with concentrated phosphoric acid) (58:42, v/v). The flow rate was set at 1.0 mL/min and the detection wavelength was set at 241 nm. The method was linear from 0.15 - 15.0 mg/L for both enantiomers. The limit of detection and the limit of quantification were 0.05 mg/L and 0.15 mg/L, respectively. The relative standard deviations (RSDs) of inter- and intra-day determination were below 0.5%. The method is easy to handle, accurate, and suitable for the quality control of the optical purity of alpha-phenylethylamine.
NASA Technical Reports Server (NTRS)
Gibson, J. S.; Rosen, I. G.
1985-01-01
In the optimal linear quadratic regulator problem for finite dimensional systems, the method known as an alpha-shift can be used to produce a closed-loop system whose spectrum lies to the left of some specified vertical line; that is, a closed-loop system with a prescribed degree of stability. This paper treats the extension of the alpha-shift to hereditary systems. As infinite dimensions, the shift can be accomplished by adding alpha times the identity to the open-loop semigroup generator and then solving an optimal regulator problem. However, this approach does not work with a new approximation scheme for hereditary control problems recently developed by Kappel and Salamon. Since this scheme is among the best to date for the numerical solution of the linear regulator problem for hereditary systems, an alternative method for shifting the closed-loop spectrum is needed. An alpha-shift technique that can be used with the Kappel-Salamon approximation scheme is developed. Both the continuous-time and discrete-time problems are considered. A numerical example which demonstrates the feasibility of the method is included.
NASA Technical Reports Server (NTRS)
Gibson, J. S.; Rosen, I. G.
1987-01-01
In the optimal linear quadratic regulator problem for finite dimensional systems, the method known as an alpha-shift can be used to produce a closed-loop system whose spectrum lies to the left of some specified vertical line; that is, a closed-loop system with a prescribed degree of stability. This paper treats the extension of the alpha-shift to hereditary systems. As infinite dimensions, the shift can be accomplished by adding alpha times the identity to the open-loop semigroup generator and then solving an optimal regulator problem. However, this approach does not work with a new approximation scheme for hereditary control problems recently developed by Kappel and Salamon. Since this scheme is among the best to date for the numerical solution of the linear regulator problem for hereditary systems, an alternative method for shifting the closed-loop spectrum is needed. An alpha-shift technique that can be used with the Kappel-Salamon approximation scheme is developed. Both the continuous-time and discrete-time problems are considered. A numerical example which demonstrates the feasibility of the method is included.
Internal consistency of the self-reporting questionnaire-20 in occupational groups
Santos, Kionna Oliveira Bernardes; Carvalho, Fernando Martins; de Araújo, Tânia Maria
2016-01-01
ABSTRACT OBJECTIVE To assess the internal consistency of the measurements of the Self-Reporting Questionnaire (SRQ-20) in different occupational groups. METHODS A validation study was conducted with data from four surveys with groups of workers, using similar methods. A total of 9,959 workers were studied. In all surveys, the common mental disorders were assessed via SRQ-20. The internal consistency considered the items belonging to dimensions extracted by tetrachoric factor analysis for each study. Item homogeneity assessment compared estimates of Cronbach’s alpha (KD-20), the alpha applied to a tetrachoric correlation matrix and stratified Cronbach’s alpha. RESULTS The SRQ-20 dimensions showed adequate values, considering the reference parameters. The internal consistency of the instrument items, assessed by stratified Cronbach’s alpha, was high (> 0.80) in the four studies. CONCLUSIONS The SRQ-20 showed good internal consistency in the professional categories evaluated. However, there is still a need for studies using alternative methods and additional information able to refine the accuracy of latent variable measurement instruments, as in the case of common mental disorders. PMID:27007682
Spacecraft attitude and velocity control system
NASA Technical Reports Server (NTRS)
Paluszek, Michael A. (Inventor); Piper, Jr., George E. (Inventor)
1992-01-01
A spacecraft attitude and/or velocity control system includes a controller which responds to at least attitude errors to produce command signals representing a force vector F and a torque vector T, each having three orthogonal components, which represent the forces and torques which are to be generated by the thrusters. The thrusters may include magnetic torquer or reaction wheels. Six difference equations are generated, three having the form ##EQU1## where a.sub.j is the maximum torque which the j.sup.th thruster can produce, b.sub.j is the maximum force which the j.sup.th thruster can produce, and .alpha..sub.j is a variable representing the throttling factor of the j.sup.th thruster, which may range from zero to unity. The six equations are summed to produce a single scalar equation relating variables .alpha..sub.j to a performance index Z: ##EQU2## Those values of .alpha. which maximize the value of Z are determined by a method for solving linear equations, such as a linear programming method. The Simplex method may be used. The values of .alpha..sub.j are applied to control the corresponding thrusters.
Fujimura, Tatsuya; Takahagi, Yoichi; Shigehisa, Tamotsu; Nagashima, Hiroshi; Miyagawa, Shuji; Shirakura, Ryota; Murakami, Hiroshi
2008-09-01
The objective of the present study was to isolate alpha 1,3-galactosyltransferase (GalGT)-gene double knockout (DKO) cells using a novel simple method of cell selection method. To obtain GalGT-DKO cells, GalGT-gene single knockout (SKO) fetal fibroblast cells were cultured for three to nine passages and GalGT-null cells were separated using a biotin-labeled IB4 lectin attached to streptavidin-coated magnetic beads. After 15-17 days of additional cultivation, seven GalGT-DKO cell colonies were obtained from a total of 2.5 x 10(7) GalGT-SKO cells. A total of 926 somatic nuclear transferred embryos reconstructed with the DKO cells were transferred into eight recipient pigs, producing four farrowed, three liveborns, and six stillborns. Absence of GalGT gene in the cloned pigs was confirmed by PCR and Southern blotting. Flow cytometric analysis revealed that alphaGal antigens were not present in the cells of the cloned DKO pigs.
X-ray Spectra and Pulse Frequency Changes in SAX J2103.5+4545
NASA Technical Reports Server (NTRS)
Baykal, A.; Stark, M. J.; Swank, J. H.; White, Nicholas E. (Technical Monitor)
2002-01-01
The November 1999 outburst of the transient pulsar SAX J2103.5+4545 was monitored with the large area detectors of the Rossi X-Ray Timing Explorer until the pulsar faded after a year. The 358 s pulsar was spun up for 150 days, at which point the flux dropped quickly by a factor of approximately 7, the frequency saturated and, as the flux continued to decline, a weak spin-down began. The pulses remained strong during the decay and the spin-up/flux correlation can be fit to the Ghosh and Lamb derivations for the spin-up caused by accretion from a thin, pressure-dominated disk, for a distance approximately 3.2 kpc and a surface magnetic field approximately 1.2 x 10(exp 13) Gauss. During the bright spin-up part of the outburst, the flux was subject to strong orbital modulation, peaking approximately 3 days after periastron of the eccentric 12.68 day orbit, while during the faint part, there was little orbital modulation. The X-ray spectra were typical of accreting pulsars, describable by a cut-off power-law, with an emission line near the 6.4 keV of Kappa(sub alpha) fluorescence from cool iron. The equivalent width of this emission did not share the orbital modulation, but nearly doubled during the faint phase, despite little change in the column density. The outburst could have been caused by an episode of increased wind from a Be star, such that a small accretion disk is formed during each periastron passage. A change in the wind and disk structure apparently occurred after 5 months such that the accretion rate was no longer modulated or the diffusion time was longer. The distance estimate implies the X-ray luminosity observed was between 1 X 10(exp 36) ergs s(exp -1) and 6 x 10(exp 34) ergs s(exp -1), with a small but definite correlation of the intrinsic power-law spectral index.
Shielding of manned space vehicles against protons and alpha particles
NASA Technical Reports Server (NTRS)
Alsmiller, R. G., Jr.; Santoro, R. T.; Barish, J.; Claiborne, H. C.
1972-01-01
The available information on the shielding of manned space vehicles against protons and alpha particles is summarized. The emphasis is placed on shielding against Van Allen belt protons and against solar-flare protons and alpha particles, but information on shielding against galactic cosmic rays is also presented. The approximation methods for use by nonexperts in the space shielding field are those that are standard in the space shielding literature.
A Bayesian sequential design using alpha spending function to control type I error.
Zhu, Han; Yu, Qingzhao
2017-10-01
We propose in this article a Bayesian sequential design using alpha spending functions to control the overall type I error in phase III clinical trials. We provide algorithms to calculate critical values, power, and sample sizes for the proposed design. Sensitivity analysis is implemented to check the effects from different prior distributions, and conservative priors are recommended. We compare the power and actual sample sizes of the proposed Bayesian sequential design with different alpha spending functions through simulations. We also compare the power of the proposed method with frequentist sequential design using the same alpha spending function. Simulations show that, at the same sample size, the proposed method provides larger power than the corresponding frequentist sequential design. It also has larger power than traditional Bayesian sequential design which sets equal critical values for all interim analyses. When compared with other alpha spending functions, O'Brien-Fleming alpha spending function has the largest power and is the most conservative in terms that at the same sample size, the null hypothesis is the least likely to be rejected at early stage of clinical trials. And finally, we show that adding a step of stop for futility in the Bayesian sequential design can reduce the overall type I error and reduce the actual sample sizes.
Reduced Fragment Diversity for Alpha and Alpha-Beta Protein Structure Prediction using Rosetta.
Abbass, Jad; Nebel, Jean-Christophe
2017-01-01
Protein structure prediction is considered a main challenge in computational biology. The biannual international competition, Critical Assessment of protein Structure Prediction (CASP), has shown in its eleventh experiment that free modelling target predictions are still beyond reliable accuracy, therefore, much effort should be made to improve ab initio methods. Arguably, Rosetta is considered as the most competitive method when it comes to targets with no homologues. Relying on fragments of length 9 and 3 from known structures, Rosetta creates putative structures by assembling candidate fragments. Generally, the structure with the lowest energy score, also known as first model, is chosen to be the "predicted one". A thorough study has been conducted on the role and diversity of 3-mers involved in Rosetta's model "refinement" phase. Usage of the standard number of 3-mers - i.e. 200 - has been shown to degrade alpha and alpha-beta protein conformations initially achieved by assembling 9-mers. Therefore, a new prediction pipeline is proposed for Rosetta where the "refinement" phase is customised according to a target's structural class prediction. Over 8% improvement in terms of first model structure accuracy is reported for alpha and alpha-beta classes when decreasing the number of 3- mers. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
USDA-ARS?s Scientific Manuscript database
A report is given on a new industrial method for the determination of carry-over alpha-amylase activity in raw and refined sugars, as well as a recommendation. In recent years, there has been increased concern over carry-over activity of mostly high temperature (HT) and very high temperature (VHT) s...
Treatment of solid tumors by interstitial release of recoiling short-lived alpha emitters
NASA Astrophysics Data System (ADS)
Arazi, L.; Cooks, T.; Schmidt, M.; Keisari, Y.; Kelson, I.
2007-08-01
A new method utilizing alpha particles to treat solid tumors is presented. Tumors are treated with interstitial radioactive sources which continually release short-lived alpha emitting atoms from their surface. The atoms disperse inside the tumor, delivering a high dose through their alpha decays. We implement this scheme using thin wire sources impregnated with 224Ra, which release by recoil 220Rn, 216Po and 212Pb atoms. This work aims to demonstrate the feasibility of our method by measuring the activity patterns of the released radionuclides in experimental tumors. Sources carrying 224Ra activities in the range 10-130 kBq were used in experiments on murine squamous cell carcinoma tumors. These included gamma spectroscopy of the dissected tumors and major organs, Fuji-plate autoradiography of histological tumor sections and tissue damage detection by Hematoxylin-Eosin staining. The measurements focused on 212Pb and 212Bi. The 220Rn/216Po distribution was treated theoretically using a simple diffusion model. A simplified scheme was used to convert measured 212Pb activities to absorbed dose estimates. Both physical and histological measurements confirmed the formation of a 5-7 mm diameter necrotic region receiving a therapeutic alpha-particle dose around the source. The necrotic regions shape closely corresponded to the measured activity patterns. 212Pb was found to leave the tumor through the blood at a rate which decreased with tumor mass. Our results suggest that the proposed method, termed DART (diffusing alpha-emitters radiation therapy), may potentially be useful for the treatment of human patients.
Chen, Yen-Ling; Shih, Chi-Jen; Ferrance, Jerome; Chang, Ya-Sian; Chang, Jan-Gowth; Wu, Shou-Mei
2009-02-13
A gold nanoparticle-filled capillary electrophoresis method combined with three multiplex polymerase chain reactions (PCRs) was established for simultaneous diagnosis of five common alpha-thalassemia deletions, including the -alpha(3.7) deletion, -alpha(4.2) deletion, Southeast Asian (--(SEA)), Filipino (--(FIL)) and Thai (--(THAI)) deletions. Gold nanoparticles (GNPs) were used as a pseudostationary phase to improve the resolution between DNA fragments in a low-viscosity polymer. To achieve the best CE separation, several parameters were evaluated for optimizing the separation conditions, including the capillary coating, the concentrations of polymer sieving matrix, the sizes and concentrations of GNPs, the buffer concentrations, and the pH. The final CE method for separating a 200-base pair (bp) DNA ladder and alpha-thalassemia deletions used a DB-17 capillary, 0.6% poly(ethylene oxide) (PEO) prepared in a mixture of GNP(32nm) solution and glycine buffer (25mM, pH 9.0) (80:20, v/v) as the sieving matrix with 1microM YO-PRO-1 for fluorescence detection; the applied voltage was -10kV (detector at anode side) and the separation temperature was 25 degrees C. Under these optimal conditions, 15 DNA fragments with sizes ranging from 0.2kb to 3.0kb were resolved within 11.5min. The RSDs of migration times were less than 2.81%. A total of 21 patients with alpha-thalassemia deletions were analyzed using this method, and all results showed good agreement with those obtained by gel electrophoresis.
Detection and characterization of a new metabolite of 17alpha-methyltestosterone.
Pozo, Oscar J; Van Eenoo, Peter; Deventer, Koen; Lootens, Leen; Van Thuyne, Wim; Parr, Maria K; Schänzer, Wilhelm; Sancho, Juan V; Hernández, Felix; Meuleman, Philip; Leroux-Roels, Geert; Delbeke, Frans T
2009-11-01
The misuse of the anabolic steroid methyltestosterone is currently routinely monitored in doping control laboratories by gas chromatography-mass spectrometry (GC-MS) of two of its metabolites: 17alpha-methyl-5beta-androstane-3alpha,17beta-diol and 17alpha-methyl-5alpha-androstane-3alpha,17beta-diol. Because of the absence of any easy ionizable moiety, these metabolites are poorly detectable using liquid chromatography-tandem mass spectrometry (LC-MS/MS) with electrospray ionization (ESI). In this study, the metabolism of methyltestosterone has been reinvestigated by the use of a precursor ion scan method in LC-ESI-MS/MS. Two metabolites have been detected using this method. Both compounds have been confirmed in postadministration urine samples of an urokinase plasminogen activator-severe combined immunodeficiency (uPA-SCID) mouse with humanized liver and were characterized by LC-MS/MS and GC-MS using both quadrupole and time of flight analyzers. From the detailed study of the fragmentation, these metabolites were proposed to be epimethyltestosterone and a dehydrogenated compound. Epimethyltestosterone has previously been described as a minor metabolite, whereas the occurrence of the oxidized metabolite has not been reported. Comparison with the synthesized reference revealed that the structure of the dehydrogenated metabolite is 6-ene-epimethyltestosterone. A selected reaction monitoring method including three transitions for each metabolite has been developed and applied to samples from an excretion study and to samples declared positive after GC-MS analysis. 6-Ene-epimethyltestosterone was found in all samples, showing its applicability in the detection of methyltestosterone misuse.
A method of evaluating quantitative magnetospheric field models by an angular parameter alpha
NASA Technical Reports Server (NTRS)
Sugiura, M.; Poros, D. J.
1979-01-01
The paper introduces an angular parameter, termed alpha, which represents the angular difference between the observed, or model, field and the internal model field. The study discusses why this parameter is chosen and demonstrates its usefulness by applying it to both observations and models. In certain areas alpha is more sensitive than delta-B (the difference between the magnitude of the observed magnetic field and that of the earth's internal field calculated from a spherical harmonic expansion) in expressing magnetospheric field distortions. It is recommended to use both alpha and delta-B in comparing models with observations.
An {alpha}-cluster model for {sub {Lambda}}{sup 9}Be spectroscopy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Filikhin, I. N., E-mail: ifilikhin@nccu.edu; Suslov, V. M.; Vlahovic, B.
An {alpha}-cluster model is applied to study low-lying spectrum of the {sub {Lambda}}{sup 9}Be hypernucleus. The three-body {alpha}{alpha}{Lambda} problem is numerically solved by the Faddeev equations in configuration space using phenomenological pair potentials. We found a set of the potentials that reproduces experimental data for the ground state (1/2{sup +}) binding energy and excitation energy of the 5/2{sup +} and 3/2{sup +} states, simultaneously. This set includes the Ali-Bodmer potential of the version 'e' for {alpha}{alpha} and modified Tang-Herndon potential for {alpha}{Lambda} interactions. The spin-orbit {alpha}{Lambda} interaction is given by modified Scheerbaum potential. Low-lying energy levels are evaluated applying amore » variant of the analytical continuation method in the coupling constant. It is shown that the spectral properties of {sub {Lambda}}{sup 9}Be can be classified as an analog of {sup 9}Be spectrum with the exception of several 'genuine hypernuclear states'. This agrees qualitatively with previous studies. The results are compared with experimental data and new interpretation of the spectral structure is discussed.« less
Novel oligorhamnosides from the stem bark of Cleistopholis glauca.
Seidel, V; Bailleul, F; Waterman, P G
2000-01-01
A reinvestigation of the stem bark of Cleistopholis glauca yielded 14 compounds, of which seven were either novel or had not been previously reported from this species. These were identified as the farnesane sesquiterpene methyl-(2E,6E)-10-oxo-3,7, 11-trimethyl-dodeca-2,6-dienoate (1); the azaanthracene alkaloid cleistopholine (4); two partially acetylated oligorhamnoside derivatives, 1-O-dodecanyl-2,3, 4-tri-O-acetyl-alpha-rhamnopyranosyl-(1-->3)-2, 4-di-O-acetyl-alpha-rhamnopyranosyl-(1-->3)-4-O-acetyl-alpha-rhamnopy ranosyl-(1-->4)-alpha-rhamnopyranoside (6) and 1-O-dodecanyl-2, 4-di-O-acetyl-alpha-rhamnopyranosyl-(1-->3)-2, 4-di-O-acetyl-alpha-rhamnopyranosyl-(1-->3)-4-O-acetyl-alpha-rhamnopy ranosyl-(1-->4)-alpha-rhamnopyranoside (8), for which the trivial names cleistetroside-7 and cleistetroside-6 were assigned, respectively; the dihydrobenzofuran neolignan rel-(2alpha, 3beta)-7-O-methylcedrusin (12); and the flavonoids dihydroquercetin (13) and quercetin (14). Structure assignments of all compounds were established by spectroscopic methods and comparison with published data. The chemosystematic significance of the occurrence of the isolated components is mentioned. Compounds 1, 6, and 8 are novel natural products.
The effect of alpha-tocopherol on the oxidation and free radical decay in irradiated UHMWPE.
Oral, Ebru; Rowell, Shannon L; Muratoglu, Orhun K
2006-11-01
We developed a radiation cross-linked ultra-high molecular weight polyethylene (UHMWPE) stabilized with alpha-tocopherol (Vitamin E) as a bearing material in total joint replacements. The stabilizing effect of alpha-tocopherol on free radical reactions in UHMWPE is not well understood. We investigated the effect of alpha-tocopherol on the oxidation and transformation of residual free radicals during real-time aging of alpha-tocopherol-doped, irradiated UHMWPE (alphaTPE) and irradiated UHMWPE (control). Samples were aged at 22 degrees C (room temperature) in air, at 40 degrees C in air and at 40 degrees C in water for 7 months. During the first month, alphaTPE showed some oxidation at the surface, which stayed constant thereafter. Control exhibited substantial oxidation in the subsurface region, which increased with time. The alkyl/allyl free radicals transformed to oxygen centered ones in both materials; this transformation occurred faster in alpha-TPE. In summary, the real-time oxidation behavior of alpha-TPE was consistent with that observed using accelerated aging methods. This new UHMWPE is oxidation resistant and is expected to maintain its properties in the long term.
Fast X-Ray Timing: A Window into the Strong-Field Regime
NASA Technical Reports Server (NTRS)
Strohmayer, Tod
2010-01-01
The dynamical time-scales in the vicinity of neutron star surfaces and black hole horizons are in the millisecond range. Over the past decade, timing signatures on such scales, either quasi-periodic oscillations (QPOs) and/or coherent pulsations, have been discovered and studied from both neutron stars and black holes with NASA's Rossi X-ray Timing Explorer, Although theoretical interpretations are still hotly debated, these timing properties almost certainly reflect the dynamics of matter in regions dominated by relativistic gravity. I will survey our current understanding of these timing properties, with a focus on how they might he used as probes of fundamental physics.
1984-01-01
TISSUE-EQUIVALENT ION CHAMBER GM - GEIGER-MUELLER COUNTER TE-GM - DIFFERENCE BETWEEN TE AND GM DATA MICRODOSE - MICRODOSIMETRY USING 0.5" ROSSI COUNTER...KERMA 4.26+8 1979 APRO NE-213+PR NEUTRON KERMA 4.26+8 1979 WWD NE-213 NEUTRON KERMA 3.10+8 > 550 KEV 1980 DREO MICRODOSE NEUTRON KERMA 4.32+8 1979...APRD GM GAMMA KERMA 3.86+7 1979 WWD NE-213 GAMMA KERMA 4.34+7 > 450 KEV 1980 DREO MICRODOSE GAMMA KERMA 3.90+7 76 1979 APRD TE TOTAL KERMA 4.50+8 50 c.c
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dasgupta-Schubert, N.; Reyes, M. A.; Tamez, V. A.
2009-04-20
Alpha decay is one of the two main decay modes of the heaviest nuclei, (SHE), and constitutes one of the dominant decay modes of highly neutron deficient medium mass nuclei ('exotics'). Thus identifying and characterizing the alpha decay chains form a crucial part of the identification of SHE. We report the extension of the previously developed method for the detailed and systematic investigation of the reliability of the three main extant analytical formulae of alpha decay half-lives: the generalized liquid drop model based formula of Royer et al. (FR), the Sobiczewski modified semi-empirical Viola-Seaborg formula (VSS) and the recent phenomenologicalmore » formula of Sobiczewski and Parkhomenko (SP)« less
[Study on chemical constituents from the roots and rhizomes of Sinopodophyllum emodi].
Sun, Yan-Jun; Li, Zhan-Lin; Chen, Hong; Zhou, Wei; Hua, Hui-Ming
2012-10-01
To investigate the chemical constituents in the roots and rhizomes of Sinopodophyllum emodi. The compounds were isolated by many different chromatographic methods such as silica gel, Sephadex LH-20, and ODS column. Their structures were identified by their physicochemical properties and spectrascopic data. Nine compounds were isolated and identified as isopicrodeoxypodophyllotoxin(I), 3beta-hydroxy-7alpha-methoxy-24beta-ethyl-cholest-5-ene(II), 5alpha, 8alpha-epidioxy-(22E,24R)-erg-osta-6,22-dien-3beta-ol(III), 7beta-hydroxysitosterol (IV), beta-sitosterol (V), daucosterol (VI), alpha-glyceryl palmitate (VII), alpha-D-glucose (VIII), 5-hydromethyl furaldehyde (IX). Compounds I - IV, VII - IX are obtained from this genus for the first time.
Spectral relationships between kicked Harper and on-resonance double kicked rotor operators
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lawton, Wayne; Mouritzen, Anders S.; Wang Jiao
2009-03-15
Kicked Harper operators and on-resonance double kicked rotor operators model quantum systems whose semiclassical limits exhibit chaotic dynamics. Recent computational studies indicate a striking resemblance between the spectra of these operators. In this paper we apply C*-algebra methods to explain this resemblance. We show that each pair of corresponding operators belongs to a common rotation C*-algebra B{sub {alpha}}, prove that their spectra are equal if {alpha} is irrational, and prove that the Hausdorff distance between their spectra converges to zero as q increases if {alpha}=p/q with p and q coprime integers. Moreover, we show that corresponding operators in B{sub {alpha}}more » are homomorphic images of mother operators in the universal rotation C*-algebra A{sub {alpha}} that are unitarily equivalent and hence have identical spectra. These results extend analogous results for almost Mathieu operators. We also utilize the C*-algebraic framework to develop efficient algorithms to compute the spectra of these mother operators for rational {alpha} and present preliminary numerical results that support the conjecture that their spectra are Cantor sets if {alpha} is irrational. This conjecture for almost Mathieu operators, called the ten Martini problem, was recently proven after intensive efforts over several decades. This proof for the almost Mathieu operators utilized transfer matrix methods, which do not exist for the kicked operators. We outline a strategy, based on a special property of loop groups of semisimple Lie groups, to prove this conjecture for the kicked operators.« less
Numerical simulation of the flow about the F-18 HARV at high angle of attack
NASA Technical Reports Server (NTRS)
Murman, Scott M.
1994-01-01
This report summarizes research done over the past two years as part of NASA Grant NCC 2-729. This research has been aimed at validating numerical methods for computing the flow about the complete F-18 HARV at alpha = 30 deg and alpha = 45 deg. At 30 deg angle of attack, the flow about the F-18 is dominated by the formation, and subsequent breakdown, of strong vortices over the wing leading-edge extensions (LEX). As the angle of attack is increased to alpha = 45 deg, the fuselage forebody of the F-18 contains significant laminar and transitional regions which are not present at alpha = 30 deg. Further, the flow over the LEX at alpha = 45 deg is dominated by an unsteady shedding in time, rather than strong coherent vortices. This complex physics, combined with the complex geometry of a full aircraft configuration, provides a challenge for current computational fluid dynamics (CFD) techniques. The following sections present the numerical method and grid generation scheme that was used, a review of prior research done to numerically model the F-18 HARV, and a discussion of the current research. The current research is broken into two main topics: the effect of engine-inlet mass-flow rate on the F-18 vortex breakdown position, and the results using a refined F-18 computational model to compute the flow at alpha = 30 deg and alpha = 45 deg.
Numerical simulation of the flow about the F-18 HARV at high angle of attack
NASA Technical Reports Server (NTRS)
Murman, Scott M.
1995-01-01
This research has been aimed at validating numerical methods for computing the flow about the complete F-18 HARV at alpha = 30 deg and alpha = 45 deg. At 30 deg angle of attack, the flow about the F-18 is dominated by the formation, and subsequent breakdown, of strong vortices over the wing leading-edge extensions (LEX). As the angle of attack is increased to alpha = 45 deg, the fuselage forebody of the F-18 contains significant laminar and transitional regions which are not present at alpha = 30 deg. Further, the flow over the LEX at alpha = 45 deg is dominated by an unsteady shedding in time, rather than strong coherent vortices. This complex physics, combined with the complex geometry of a full-aircraft configuration, provides a challenge for current computational fluid dynamics (CFD) techniques. The following sections present the numerical method and grid generation scheme that was used, a review of prior research done to numerically model the F-18 HARV, and a discussion of the current research. The current research is broken into three main topics; the effect of engine-inlet mass-flow rate on the F-18 vortex breakdown position, the results using a refined F-18 computational model to compute the flow at alpha = 30 deg and alpha = 45 deg, and research done using the simplified geometry of an ogive-cylinder configuration to investigate the physics of unsteady shear-layer shedding. The last section briefly summarizes the discussion.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Chun-Chieh; Department of Medical Imaging and Radiological Science, Chang Gung University School of Medicine, Taoyuan, Taiwan; Lai, Chyong-Huey
Purpose: To study the prognostic value of the human papillomavirus (HPV) genotypes in cervical cancer patients undergoing radiotherapy. Patients and Methods: A total of 1,010 patients with cervical cancer after radiotherapy between 1993 and 2000 were eligible for this study. The HPV genotypes were determined by a genechip, which detects 38 types of HPV. The patient characteristics and treatment outcomes were analyzed using the Cox regression hazard model and classification and regression tree decision tree method. Results: A total of 25 genotypes of HPV were detected in 992 specimens (98.2%). The leading 8 types were HPV16, 58, 18, 33, 52,more » 39, 31, and 45. These types belong to two high-risk HPV species: alpha-7 (HPV18, 39, 45) and alpha-9 (HPV16, 31, 33, 52, 58). Three HPV-based risk groups, which were independent of established prognostic factors, such as International Federation of Gynecology and Obstetrics stage, age, pathologic features, squamous cell carcinoma antigen, and lymph node metastasis, were associated with the survival outcomes. The high-risk group consisted of the patients without HPV infection or the ones infected with the alpha-7 species only. Patients co-infected with the alpha-7 and alpha-9 species belonged to the medium-risk group, and the others were included in the low-risk group. Conclusion: The results of the present study have confirmed the prognostic value of HPV genotypes in cervical cancer treated with radiotherapy. The different effect of the alpha-7 and alpha-9 species on the radiation response deserves additional exploration.« less
Gharesi-Fard, Behrouz; Zolghadri, Jaleh; Kamali-Sarvestani, Eskandar
2008-03-01
Considering the deleterious role of T helper1 (Th1) cells in pregnancy outcome, a successful treatment for recurrent spontaneous abortion (RSA) should be able to make a significant shift away from Th1 responses. Although paternal leukocyte immunization has been used for treatment of RSA for years, because of methodological differences there is no consensus on the mechanism of action and effectiveness of this method. Twenty-five Iranian non-pregnant women with RSA and 16 non-pregnant control women with at least two successful pregnancies were included in this study. All cases were followed up after leukocyte therapy for pregnancy outcome. Mononuclear cells from women were co-cultured with the husband's mononuclear cells before and after immunotherapy. The levels of tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) were checked on culture supernatant by enzyme-linked immunosorbent assay method. The mean concentration of TNF-alpha was significantly higher in patients compared with that in normal controls (P=0.0001). After immunotherapy, the TNF-alpha level was only significantly decreased in women with successful outcome (P=0.0001). Immunotherapy also induced a significant reduction in the IFN-gamma level (P=0.009). The results of this investigation confirm the role of TNF-alpha in RSA and propose the assessment of TNF-alpha production as a valuable prognostic parameter for the prediction of abortion after leukocyte therapy.
Rapid determination of 210Po in water samples
DOE Office of Scientific and Technical Information (OSTI.GOV)
Maxwell, Sherrod L.; Culligan, Brian K.; Hutchison, Jay B.
2013-08-02
A new rapid method for the determination of 210Po in water samples has been developed at the Savannah River National Laboratory (SRNL) that can be used for emergency response or routine water analyses. If a radiological dispersive device (RDD) event or a radiological attack associated with drinking water supplies occurs, there will be an urgent need for rapid analyses of water samples, including drinking water, ground water and other water effluents. Current analytical methods for the assay of 210Po in water samples have typically involved spontaneous auto-deposition of 210Po onto silver or other metal disks followed by counting by alphamore » spectrometry. The auto-deposition times range from 90 minutes to 24 hours or more, at times with yields that may be less than desirable. If sample interferences are present, decreased yields and degraded alpha spectrums can occur due to unpredictable thickening in the deposited layer. Separation methods have focused on the use of Sr Resin, often in combination with 210Pb analysis. A new rapid method for 210Po in water samples has been developed at the Savannah River National Laboratory (SRNL) that utilizes a rapid calcium phosphate co-precipitation method, separation using DGA Resin (N,N,N,N-tetraoctyldiglycolamide extractant-coated resin, Eichrom Technologies or Triskem-International), followed by rapid microprecipitation of 210Po using bismuth phosphate for counting by alpha spectrometry. This new method can be performed quickly with excellent removal of interferences, high chemical yields and very good alpha peak resolution, eliminating any potential problems with the alpha source preparation for emergency or routine samples. A rapid sequential separation method to separate 210Po and actinide isotopes was also developed. This new approach, rapid separation with DGA Resin plus microprecipitation for alpha source preparation, is a significant advance in radiochemistry for the rapid determination of 210Po.« less
NASA Astrophysics Data System (ADS)
Kim, Bong-Sik
Three dimensional (3D) Navier-Stokes-alpha equations are considered for uniformly rotating geophysical fluid flows (large Coriolis parameter f = 2O). The Navier-Stokes-alpha equations are a nonlinear dispersive regularization of usual Navier-Stokes equations obtained by Lagrangian averaging. The focus is on the existence and global regularity of solutions of the 3D rotating Navier-Stokes-alpha equations and the uniform convergence of these solutions to those of the original 3D rotating Navier-Stokes equations for large Coriolis parameters f as alpha → 0. Methods are based on fast singular oscillating limits and results are obtained for periodic boundary conditions for all domain aspect ratios, including the case of three wave resonances which yields nonlinear "2½-dimensional" limit resonant equations for f → 0. The existence and global regularity of solutions of limit resonant equations is established, uniformly in alpha. Bootstrapping from global regularity of the limit equations, the existence of a regular solution of the full 3D rotating Navier-Stokes-alpha equations for large f for an infinite time is established. Then, the uniform convergence of a regular solution of the 3D rotating Navier-Stokes-alpha equations (alpha ≠ 0) to the one of the original 3D rotating NavierStokes equations (alpha = 0) for f large but fixed as alpha → 0 follows; this implies "shadowing" of trajectories of the limit dynamical systems by those of the perturbed alpha-dynamical systems. All the estimates are uniform in alpha, in contrast with previous estimates in the literature which blow up as alpha → 0. Finally, the existence of global attractors as well as exponential attractors is established for large f and the estimates are uniform in alpha.
Development of Bioorthogonally Degradable Linkers and Polymers Using alpha-Azidoethers
NASA Astrophysics Data System (ADS)
Rajagopalan, Chandrasekhar Ramasubramanian
Degradable polymers have gained a lot of attention in recent years for applications in biotechnology and medicine. External control over polymer degradation can be obtained by incorporating functional groups that cleave in the presence of triggers that would normally be absent in biological environments, i.e. are bioorthogonal. This thesis explores the use of chemically cleavable alpha-azidoethers as a new method to obtain external control over the degradation behavior of polymers. My first goal is to illustrate the potential of alpha-azidoethers toward developing cleavable linkers. We have studied the relationship between alpha-azidoether structure and hydrolytic stability, to prepare linkers that withstand background hydrolytic cleavage until they are exposed to the cleaving trigger. The cleavage kinetics of the alpha-azidoether functional group was quantified. In addition to the conventionally used tris(2-carboxyethyl)phosphine (TCEP), dihydrolipoic acid (DHLA), a previously unexplored, biocompatible reducing agent, was also evaluated as a cleaving trigger. Based on these results, we have proposed design rules for utilizing alpha-azidoethers as cleavable linkers in applications that require bioorthogonal control over linker cleavage. Secondly, the alpha-azidoether cleavable linker chemistry was implemented into the development of polymeric materials. Two different types of polymers were developed. Polyamides incorporating alpha-azidoethers along the backbone were synthesized, and their physical properties and chemically triggered degradation behavior were characterized. The degradation timescale of these polymers can be tuned simply by manipulating the concentration of the externally applied chemical trigger. The alpha-azidoether functional group was then utilized to develop a unique triggered-release polymeric adhesive for potential applications in dental adhesive formulations. A methacrylamide-phosphonate adhesive monomer incorporating an alpha-azidoether group was designed and synthesized. The monomer was polymerized to adhere polymer-composite substrates. Adhesion strength was quantified, and on-demand release of bonded substrates was demonstrated using DHLA as a trigger. The results presented here shed some light on the scope, advantages and drawbacks of utilizing alpha-azidoethers to develop new types of cleavable linkers and degradable polymers. In principle, the triggered degradation method described here could be incorporated into polymers with different chemical structures, to develop a variety of materials that offer an external control over degradation.
McClintock, Jennifer L; Ceresa, Brian P
2010-07-01
PURPOSE. The goal of this study was to determine the molecular mechanism by which transforming growth factor-alpha (TGF-alpha) is a more potent activator of epidermal growth factor receptor (EGFR)-mediated corneal wound healing than epidermal growth factor (EGF). METHODS. Telomerase immortalized human corneal epithelial (hTCEpi) cells and primary human corneal epithelial cells were tested for their ability to migrate in response to EGF and TGF-alpha. In parallel, the endocytic trafficking of the EGFR in response to these same ligands was examined using indirect immunofluorescence, immunoblots, and radioligand binding. RESULTS. TGF-alpha, compared with EGF, is a more potent activator of corneal epithelial cell migration. Although both TGF-alpha and EGF were able to induce EGFR internalization and phosphorylation, only those receptors that were stimulated with EGF progressed to lysosomal degradation. EGFRs stimulated with TGF-alpha recycled back to the plasma membrane, where they could be reactivated with ligand. CONCLUSIONS. This study reveals that EGFR-mediated cell migration is limited by ligand-stimulated downregulation of the EGFR. This limitation can be overcome by treating cells with TGF-alpha because TGF-alpha stimulates EGFR endocytosis, but not degradation. After internalization of the TGF-alpha/EGFR complex, EGFR recycles back to the plasma membrane, where it can be restimulated. This sequence of events provides the receptor multiple opportunities for stimulation. Thus, stimulation with TGF-alpha prolongs EGFR signaling compared with EGF.
Yazawa, S; Kochibe, N; Nishimura, T; Shima, C; Takai, I; Adachi, M; Asao, T; Hada, T; Enoki, Y; Juneja, L R
1998-09-01
A new method for determination of alpha1,6fucosyltransferase activity has been described. Recently, the disialyl-biantennary undecasaccharide was prepared in high yield from egg yolk [(1996), Carbohydr Lett 2: 137-42]. By treatment of this oligosaccharide with neuraminidase and beta-galactosidase, we readily obtained an asialo-agalacto-biantennary heptasaccharide (GlcNAcbeta 1,2Manalpha1,6[GlcNAcbeta1,2Manalpha1,3]Manbeta1 ,4GlcNAcbeta1,4GlcNAc). Using this asialo-agalacto-oligosaccharide as an acceptor, fucosyltransferases from human plasma and extracts of various human hepatoma cell lines were assayed in the presence of GDP-[3H]fucose. The reaction mixture was applied to a column of GlcNAc-binding, Psathyrella velutina lectin coupled gel. All the fucosylated acceptor were bound to the column which was eluted with 50 mM GlcNAc. Structural analyses revealed that only the innermost GlcNAc residue of the acceptor was fucosylated through an alpha1,6-linkage, and the oligosaccharide prepared could be used as a specific acceptor for alpha1,6fucosyltransferase. The present method was used to screen plasma alpha1,6fucosyltransferase in several patient groups, and significantly elevated activities were found in samples from patients with liver diseases, including chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma.
McDonald, Mark; Malone, Edward; McBride, John
2010-01-01
A novel and rapid method was developed and validated for the confirmation of endogenous and synthetic hormones in animal serum using LC/MS/MS. Detection of 17 beta-estradiol and beta-testosterone below the respective European Union-recommended levels of 0.1 and 0.5 microg/L was achieved, as was a required performance level of 0.1 microg/L for 17 alpha-estradiol and 0.5 microg/L for 17 alpha-testosterone, medroxyprogesterone-17-acetate, and progesterone. The method was established with dilution of serum followed by ion-exchange SPE, LC separation and MS detection with electrospray ionization, selected reaction monitoring, and positivelnegative switching. Two characteristic transitions were monitored for each analyte. The method was applied to bovine, ovine, porcine, equine, and avian samples and validated according to European Commission Decision 2002/657/EC and accepted for ISO/IEC 17025:2005 accreditation. An extended calibration curve allows naturally occurring levels of endogenous hormones to be quantified. Recoveries ranged from 97.3% for 17 alpha-testosterone to 102.0% for 17 alpha-estradiol. The decision limit CCalpha ranged from 0.02 microg/L for 17 alpha- and beta-estradiol to 0.12 microg/L for progesterone. Detection capability CCbeta ranged from 0.03 microg/L for 17 a-estradiol to 0.20 microg/L for progesterone.
Disposable cartridge extraction of retinol and alpha-tocopherol from fatty samples.
Bourgeois, C F; Ciba, N
1988-01-01
A new approach is proposed for liquid/solid extraction of retinol and alpha-tocopherol from samples, using a disposable kieselguhr cartridge. The substitution of the mixture methanol-ethanol-n-butanol (4 + 3 + 1) for methanol in the alkaline hydrolysis solution makes it now possible to process fatty samples. Methanol is necessary to solubilize the antioxidant ascorbic acid, and a linear chain alcohol such as n-butanol is necessary to reduce the size of soap micelles so that they can penetrate into the kieselguhr pores. In comparisons of the proposed method with conventional methods on mineral premixes and fatty feedstuffs, recovery and accuracy are at least as good by the proposed method. Advantages are increased rate of determinations and the ability to hydrolyze and extract retinol and alpha-tocopherol together from the same sample.
Isotopic analysis of uranium in natural waters by alpha spectrometry
Edwards, K.W.
1968-01-01
A method is described for the determination of U234/U238 activity ratios for uranium present in natural waters. The uranium is coprecipitated from solution with aluminum phosphate, extracted into ethyl acetate, further purified by ion exchange, and finally electroplated on a titanium disc for counting. The individual isotopes are determined by measurement of the alpha-particle energy spectrum using a high resolution low-background alpha spectrometer. Overall chemical recovery of about 90 percent and a counting efficiency of 25 percent allow analyses of water samples containing as little as 0.10 ?g/l of uranium. The accuracy of the method is limited, on most samples, primarily by counting statistics.
EEG alpha spindle measures as indicators of driver fatigue under real traffic conditions.
Simon, Michael; Schmidt, Eike A; Kincses, Wilhelm E; Fritzsche, Martin; Bruns, Andreas; Aufmuth, Claus; Bogdan, Martin; Rosenstiel, Wolfgang; Schrauf, Michael
2011-06-01
The purpose of this study is to show the effectiveness of EEG alpha spindles, defined by short narrowband bursts in the alpha band, as an objective measure for assessing driver fatigue under real driving conditions. An algorithm for the identification of alpha spindles is described. The performance of the algorithm is tested based on simulated data. The method is applied to real data recorded under real traffic conditions and compared with the performance of traditional EEG fatigue measures, i.e. alpha-band power. As a highly valid fatigue reference, the last 20 min of driving from participants who aborted the drive due to heavy fatigue were used in contrast to the initial 20 min of driving. Statistical analysis revealed significant increases from the first to the last driving section of several alpha spindle parameters and among all traditional EEG frequency bands, only of alpha-band power; with larger effect sizes for the alpha spindle based measures. An increased level of fatigue over the same time periods for drop-outs, as compared to participants who did not abort the drive, was observed only by means of alpha spindle parameters. EEG alpha spindle parameters increase both fatigue detection sensitivity and specificity as compared to EEG alpha-band power. It is demonstrated that alpha spindles are superior to EEG band power measures for assessing driver fatigue under real traffic conditions. Copyright © 2011 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.
Glycosidases induced in Aspergillus tamarii. Mycelial alpha-D-galactosidases.
Civas, A; Eberhard, R; Le Dizet, P; Petek, F
1984-01-01
Two alpha-D-galactosidases (alpha-D-galactoside galactohydrolase, EC 3.2.1.22) produced by Aspergillus tamarii were purified from the mycelial extract by a procedure including chromatography on hydroxyapatite, DEAE-cellulose and ECTEOLA-cellulose. Each of these enzymes showed a single protein band corresponding to the alpha-D-galactosidase activity when examined by polyacrylamide-gel electrophoresis. They catalysed the hydrolysis of o-nitrophenyl alpha-D-galactoside, melibiose, raffinose and stachyose, but did not attack the galactomannans. Their Mr values were respectively 265000 +/- 5000 and 254000 +/- 5000 by the method of Hedrick & Smith [(1968) Arch. Biochem. Biophys. 126, 155-164]. Polyacrylamide-gel electrophoresis in the presence of sodium dodecyl sulphate in each case showed a single protein band, with Mr 88000 and 77500 respectively. The purified enzymes contained carbohydrate, consisting of N-acetylglucosamine, mannose, glucose and galactose in the estimated molar proportions of 1:9:5:8 in alpha-galactosidase I. Images Fig. 1. PMID:6331398
Ping, Jian; Chen, Hong-Yun; Yang, Zhou; Yang, Cheng; Xu, Lie-Ming
2014-03-01
To observe the effect of Yiguan Decoction (YGD) on differentiation of bone marrow mesenchymal stem cells (BMSCs) into hepatocyte-like cells in vitro. Rat BMSCs were isolated using whole bone marrow adherent method. The properties of BMSCs were identified by analyzing the expression of surface cytokines by flow cytometry. The third passage cells were differentiated into fat cells to identify their features. BMSCs were incubated with hepatocyte growth factor (HGF) plus fibroblast growth factor 4 (FGF4) or YGD containing serum YGD for 21 days. The mRNA expression of alpha-fetoprotein (alphaAFP), albumin (Alb), and hepatocyte nuclear factor 4alpha (HNF4alpha) were detected by real time PCR. Expression of AFP and cytokeratin 18 (CK18) protein was detected by cell immunofluorescence. Glycogen synthesis was observed using periodic acid-Schiff stain (PAS). CK18, Wnt 3alpha, and alphacatenin protein expressions were detected by Western blot. High expression of CD90, CD29, and CD44, and low expression of CD34 and CD11b were observed in BMSCs isolated by whole bone mar- row adherent method, and numerous lipid droplets were observed in BMSCs using oil red O staining. Both YGD containing serum and growth factor stimulated the expression levels of Alb, AFP, HNF4alpha mRNA and CK18 protein. The down-regulated expression of Wnt 3alpha and beta-catenin could be detected at 21 days after induction. The synthesized glycogen granule could be seen. Down-regulated Wnt 3alpha and beta-catenin expression could also be observed. YGD could induce the differentiation of rat BMSCs into hepatocyte-like cells, which was related to down-regulating Wnt/beta-catenin signal pathway.
USDA-ARS?s Scientific Manuscript database
An LC-MS/MS method was developed and validated to determine 7alpha-OH cholesterol in liver microsome. This method was convenient and fast with high specificity and sensitivity. Briefly, a gradient elution was performed on a Synergi polar-C18 column (50 x 4.6mm i.d., 3microm). The mobile phase (cons...
Hight, Darren; Voss, Logan J; Garcia, Paul S; Sleigh, Jamie
2017-01-01
Oscillations in the electroencephalogram (EEG) at the alpha frequency (8-12 Hz) are thought to be ubiquitous during surgical anesthesia, but the details of how this oscillation responds to ongoing changes in volatile anesthetic concentration have not been well characterized. It is not known how often alpha oscillations are absent in the clinical context, how sensitively alpha frequency and power respond to changes in anesthetic concentration, and what effect increased age has on alpha frequency. Bipolar EEG was recorded frontally from 305 patients undergoing surgery with sevoflurane or desflurane providing general anesthesia. A new method of detecting the presence of alpha oscillations based on the stability of the rate of change of the peak frequency in the alpha range was developed. Linear concentration-response curves were fitted to assess the sensitivity of alpha power and frequency measures to changing levels of anesthesia. Alpha oscillations were seen to be inexplicably absent in around 4% of patients. Maximal alpha power increased with increasing volatile anesthetic concentrations in half of the patients, and decreased in the remaining patients. Alpha frequency decreased with increasing anesthetic concentrations in near to 90% of patients. Increasing age was associated with decreased sensitivity to volatile anesthesia concentrations, and with decreased alpha frequency, which sometimes transitioned into the theta range (5-7 Hz). While peak alpha frequency shows a consistent slowing to increasing volatile concentrations, the peak power of the oscillation does not, suggesting that frequency might be more informative of depth of anesthesia than traditional power based measures during volatile-based anesthesia. The alpha oscillation becomes slower with increasing age, even when the decreased anesthetic needs of older patients were taken into account.
Tang, Shenjie; Xiao, Heping; Fan, Yihu; Wu, Furong; Zhang, Zhongshun; Li, Hong; Yang, Yan
2002-06-01
OBJECTIVE To investigate the characteristics and clinical value of serum tumor necrosis factor-alpha (TNF-alpha) and its receptor (sTNF-R), interleukin-1beta(IL-1beta) and its receptor(IL-1R), interleukin-6(IL-6) and its receptor(IL-6R) in patients with pulmonary tuberculosis, and to evaluate their role in the immunopathogenesis of tuberculosis. METHODS The serum levels of TNF-alpha, sTNF-R Iota IL-1beta,IL-1R, IL-6 and IL-6R were measured using the sandwich ABC-ELISA method in 41 cases of active tuberculosis, 21 cases of inactive tuberculosis and 20 normal controls. The serum levels of the cytokines in 17 cases of active tuberculos is were followed. RESULTS The serum levels of TNF-alpha sTNF-RIota IL-1beta,IL-1R, IL-6 IL-6R and the TNF-alpha/sTNF-RIota ratio were significantly higher in both the active and the inactive tuberculosis groups than those in normal controls (P <0.01 approximately 0.05). The TNF-alpha sTNF-R Iota IL-1 beta, IL-1R, IL-6 IL-6R levels and the TNF-alpha/sTNF-R Iota ratio in the active tuberculosis group were significantly higher than those in the inactive tuberculosis(P <0.01 approximately 0.05). The serum levels of TNF-alpha sTNF-R Iota, IL-1beta and IL-6 and the TNF-alpha,/sTNF-R Iota ratio were significantly lower in cavernous tuberculosis than those in non- cavernous tuberculosis (P < 0.01 approximately 0.05). After 2 months' antituberculosis treatment, the serum levels of TNF-alpha,sTNF-R Iota IL-1 beta, IL-1R,IL-6, IL-6R and the TNF-alpha/sTNF-R Iota ratio in 15(15/17) cases were significantly lower than those before treatment(P < 0.01 approximately 0.05). CONCLUSIONS TNF-alpha, IL-1 beta, IL-6 and their receptors may be involved in the immunopathogenesis of tuberculosis. Measuring the serum levels of proinflammatory cytokines and their receptors may be useful in evaluating the activity, the clinical pattern, and the prognosis of the disease and monitoring the clinical effect of antituberculous therapy.
Growth and Characterization of alpha-PbO for Room Temperature Radiation Detection
NASA Astrophysics Data System (ADS)
Ford, Erin Leigh
A global trading structure and high throughput of shipping containers into ports around the world increases the chance of nuclear terrorism via cargo containers. Harmless radioactive sources confuse and impede detection of the materials that pose a real threat, making spectroscopy difficult and requiring detectors with high resolution. The current methods that are used to check containers in ports have security flaws, and only 5% of all shipping containers are checked. The development of semiconductor gamma-ray detectors is one of the protocols being advanced to alleviate this risk because they can function at room temperature and they are cost effective, easily produced, and have high resolution. This dissertation has addressed the current lack of "perfect" room temperature detector materials by investigating alpha-PbO, a novel material in this field. This includes the development of a growth process for alpha-PbO thin films, as well as its structural and performance characterization as a detector material. Because we intend alpha-PbO to be a photoconductive detector, it should have certain properties. A photoconductive detector consists of a highly resistive material with a voltage bias across it. It absorbs incident gamma-rays, creating electron-hole pairs that provide a signal. To function well, it must have a high atomic number and a high density in order to absorb high-energy photons via the photoelectric effect. It should also have a large resistivity and a wide band gap to avoid large leakage currents at room temperature. Finally, it must have good charge carrier transport properties and detector resolution in order to be able to determine the characteristic energy peaks of the radiation-emitting source. We chose alpha-PbO because it has a very high Z and a very high density and a band gap in the correct range. It also has a rich history of use as a photoconductor that reaches back to the 1950s. Numerous methods have been used to grow thin films of alpha-PbO. However, rarely are those films single phase or highly oriented. Pulsed laser deposition provides a method to grow epitaxial thin films of alpha-PbO. The structure of the grown films was characterized using X-ray diffraction 2θ-o scans, rocking curves, and reciprocal space mapping. Feedback from a parameterized study of the structural characterization enabled optimization of the growth process to improve the quality of the thin films. The methods used for the optical measurement of alpha-PbO films included absorption spectroscopy and ellipsometry. Determination of the spectral absorption coefficient was achieved by transmission spectroscopy and reflection spectroscopy via a PerkinElmer Lambda 950 UV-Vis spectrophotometer. Study of the electronic and transport properties of alpha-PbO is important in order to understand how the material will behave as a radiation detector. Spectral photoconductivity was measured to ensure that alpha-PbO's response to light was large enough for it to be a useful detector material and to confirm the band gap measurements. In the field of detector materials, the mutau-product is commonly used as a figure of merit because it enables a measurement of the trapping length of the charge carriers within the detector. Many's equation, which is a derivation of the photocurrent with respect to the applied voltage across a wide band gap semiconductor, is one of the methods used to determine the mutau-product. The photocurrent voltage measurements were obtained from the 0.5 V to 80 V range. This data was difficult to fit with Many's equation over that whole range. Higher voltages displayed deviation from ideal behavior due to the contact effects, but at the lower voltages the data were unaffected. Fits to the lower voltage range, from 0.5 V to 10 V, yielded mutau = 6.8 x 10-4 cm2/V. Room temperature photoconductors will ultimately be used to detect gamma-rays; however, thin films do not have enough stopping power to absorb the total energy of a gamma-ray. Therefore, we study the alpha-PbO detector response to radiation in the form of alpha particles because they are large, charged, and relatively easy to stop. SRIM calculation estimated that alpha particles have a range of up to 16 mum in alpha-PbO. The initial long-duration film growth yielded films that were ˜ 8 mum thick. Therefore, a full energy peak from alpha particles was not seen in alpha-PbO. We did see a shoulder protruding out of the noise peak due to the charge carriers that were created before the alpha particles escaped the detector volume. (Abstract shortened by UMI.)
Microwave sintering of sol-gel derived abrasive grain
Plovnick, Ross; Celikkaya, Ahmet; Blake, Rodger D.
1997-01-01
A method is provided for making microwave-sintered, free flowing alpha alumina-based ceramic abrasive grain, under conditions effective to couple microwaves with calcined alpha alumina-based abrasive gain precursor and sinter it at a temperature of at least about 1150.degree. C.
NASA Astrophysics Data System (ADS)
Cantini, Federico; Pio Rossi, Angelo; Orosei, Roberto; Baumann, Peter; Misev, Dimitar; Oosthoek, Jelmer; Beccati, Alan; Campalani, Piero; Unnithan, Vikram
2014-05-01
MARSIS is an orbital synthetic aperture radar for both ionosphere and subsurface sounding on board ESA's Mars Express (Picardi et al. 2005). It transmits electromagnetic pulses centered at 1.8, 3, 4 or 5 MHz that penetrate below the surface and are reflected by compositional and/or structural discontinuities in the subsurface of Mars. MARSIS data are available as a collection of single orbit data files. The availability of tools for a more effective access to such data would greatly ease data analysis and exploitation by the community of users. For this purpose, we are developing a database built on the raster database management system RasDaMan (e.g. Baumann et al., 1994), to be populated with MARSIS data and integrated in the PlanetServer/EarthServer (e.g. Oosthoek et al., 2013; Rossi et al., this meeting) project. The data (and related metadata) are stored in the db for each frequency used by MARSIS radar. The capability of retrieving data belonging to a certain orbit or to multiple orbit on the base of latitute/longitude boundaries is a key requirement of the db design, allowing, besides the "classical" radargram representation of the data, and in area with sufficiently hight orbit density, a 3D data extraction, subset and analysis of subsurface structures. Moreover the use of the OGC WCPS (Web Coverage Processing Service) standard can allow calculations on database query results for multiple echoes and/or subsets of a certain data product. Because of the low directivity of its dipole antenna, MARSIS receives echoes from portions of the surface of Mars that are distant from nadir and can be mistakenly interpreted as subsurface echoes. For this reason, methods have been developed to simulate surface echoes (e.g. Nouvel et al., 2004), to reveal the true origin of an echo through comparison with instrument data. These simulations are usually time-consuming, and so far have been performed either on a case-by-case basis or in some simplified form. A code for parallel computing has been developed and tested on a Tier 0 class HPC cluster computer located at CINECA, Bologna, Italy, to produce accurate simulations for the entire MARSIS dataset. Although the necessary computational resources have not yet been secured, through the HPC cluster at Jacobs University in Bremen it was possible to simulate a significant subset of orbits covering the area of the Medusae Fossae Formation (MFF), a seeimingly soft, easily eroded deposit that extends for nearly 1,000 km along the equator of Mars (e.g. Watters et al., 2007; Carter et al., 2009). Besides the MARSIS data, simulation of MARSIS surface clutter signal are included in the db to further improve its scientific value. Simulations will be available throught the project portal to end users/scientists and they will eventually be provided in the PSA/PDS archives. References: Baumann, P. On the management of multidimensional discrete data. VLDB J. 4 (3), 401-444, Special Issue on Spatial Database Systems, 1994. Carter, L. M., Campbell, B. A., Watters, T. R., Phillips, R. J., Putzig, N. E., Safaeinili, A., Plaut, J., Okubo, C., Egan, A. F., Biccari, D., Orosei, R. (2009). Shallow radar (SHARAD) sounding observations of the Medusae Fossae Formation, Mars. Icarus, 199(2), 295-302. Nouvel, J.-F., Herique, A., Kofman, W., Safaeinili, A. 2004. Radar signal simulation: Surface modeling with the Facet Method. Radio Science 39, 1013. Oosthoek, J.H.P, Flahaut J., Rossi, A. P., Baumann, P., Misev, D., Campalani, P., Unnithan, V. (2013) PlanetServer: Innovative Approaches for the Online Analysis of Hyperspectral Satellite Data from Mars, Advances in Space Research. DOI: 10.1016/j.asr.2013.07.002 Picardi, G., and 33 colleagues 2005. Radar Soundings of the Subsurface of Mars. Science 310, 1925-1928. Rossi, A. P., Baumann, P., Oosthoek, J., Beccati, A., Cantini, F., Misev, D. Orosei, R., Flahaut, J., Campalani, P., Unnithan, V. (2014),Geophys. Res. Abs., Vol. 16, #EGU2014-5149, this meeting. Watters, T. R., Campbell, B., Carter, L., Leuschen, C. J., Plaut K., Picardi, G., Orosei R., Safaenili, A., Clifford, S. M., Farrell, W. M., Ivanov, A. B., Phillips, R. J., Stofan, E. R. (2007) Radar Sounding of the Medusae Fossae Formation Mars: Equatorial Ice or Dry, Low-Density Deposits?. Science 318, 1125.
Chan, Steven; Raynor, Geoffrey Stephen; Shwarts, Erik; Shanahan, Meghan; Landman, Adam B
2016-01-01
Background There are over 165,000 mHealth apps currently available to patients, but few have undergone an external quality review. Furthermore, no standardized review method exists, and little has been done to examine the consistency of the evaluation systems themselves. Objective We sought to determine which measures for evaluating the quality of mHealth apps have the greatest interrater reliability. Methods We identified 22 measures for evaluating the quality of apps from the literature. A panel of 6 reviewers reviewed the top 10 depression apps and 10 smoking cessation apps from the Apple iTunes App Store on these measures. Krippendorff’s alpha was calculated for each of the measures and reported by app category and in aggregate. Results The measure for interactiveness and feedback was found to have the greatest overall interrater reliability (alpha=.69). Presence of password protection (alpha=.65), whether the app was uploaded by a health care agency (alpha=.63), the number of consumer ratings (alpha=.59), and several other measures had moderate interrater reliability (alphas>.5). There was the least agreement over whether apps had errors or performance issues (alpha=.15), stated advertising policies (alpha=.16), and were easy to use (alpha=.18). There were substantial differences in the interrater reliabilities of a number of measures when they were applied to depression versus smoking apps. Conclusions We found wide variation in the interrater reliability of measures used to evaluate apps, and some measures are more robust across categories of apps than others. The measures with the highest degree of interrater reliability tended to be those that involved the least rater discretion. Clinical quality measures such as effectiveness, ease of use, and performance had relatively poor interrater reliability. Subsequent research is needed to determine consistent means for evaluating the performance of apps. Patients and clinicians should consider conducting their own assessments of apps, in conjunction with evaluating information from reviews. PMID:26863986
El Raziky, Maissa; Fathalah, Waleed Fouad; Zakaria, Zeinab; Eldeen, Hadeel Gamal; Abul-Fotouh, Amr; Salama, Ahmed; Awad, Abubakr; Esmat, Gamal; Mabrouk, Mahasen
2016-05-01
Despite the appearance of new oral antiviral drugs, pegylated interferon (PEG-IFN)/RBV may remain the standard of care therapy for some time, and several viral and host factors are reported to be correlated with therapeutic effects. This study aimed to reveal the independent variables associated with failure of sustained virological response (SVR) to PEG-IFN alpha-2a versus PEG-IFN alpha-2b in treatment of naive chronic hepatitis C virus (HCV) Egyptian patients using both statistical methods and data mining techniques. This retrospective cohort study included 3,235 chronic hepatitis C patients enrolled in a large Egyptian medical center: 1,728 patients had been treated with PEG-IFN alpha-2a plus ribavirin (RBV) and 1,507 patients with PEG-IFN alpha-2b plus RBV between 2007 and 2011. Both multivariate analysis and Reduced Error Pruning Tree (REPTree)-based model were used to reveal the independent variables associated with treatment response. In both treatment types, alpha-fetoprotein (AFP) >10 ng/mL and HCV viremia >600 × 10(3) IU/mL were the independent baseline variables associated with failure of SVR, while male gender, decreased hemoglobin, and thyroid-stimulating hormone were the independent variables associated with good response (P < 0.05). Using REPTree-based model showed that low AFP was the factor of initial split (best predictor) of response for either PEG-IFN alpha-2a or PEG-IFN alpha-2b (cutoff value 8.53, 4.89 ng/mL, AUROC = 0.68 and 0.61, P = 0.05). Serum AFP >10 ng/mL and viral load >600 × 10(3) IU/mL are variables associated with failure of response in both treatment types. REPTree-based model could be used to assess predictors of response.
Eriksson, Hannah K; Nordström, Jakob; Gabrysch, Katja; Hailer, Nils P; Lazarinis, Stergios
2018-05-01
Measuring alpha-defensin concentrations in synovial fluid may help to diagnose periprosthetic joint infection (PJI). There are two commercially available methods for measuring alpha-defensin in synovial fluid: the enzyme-linked immunosorbent assay-based Synovasure® alpha-defensin immunoassay, which gives a numeric readout within 24 hours, and the Synovasure lateral flow test, which gives a binary readout within 20 minutes. There is no compilation of the existing literature to support the use of one of these two tests over the other. Does the immunoassay or the lateral flow test have better diagnostic value (sensitivity and specificity) in diagnosing PJI? We followed PRISMA guidelines and identified all studies on alpha-defensin concentration in synovial fluid as a PJI diagnostic marker, indexed to April 14, 2017, in PubMed, JSTOR, Google Scholar, and OVID databases. The search retrieved 1578 records. All prospective and retrospective studies on alpha-defensin as a PJI marker (PJI classified according to the criteria of the Musculoskeletal Infection Society) after THA or TKA were included in the analysis. All studies used only one of the two commercially available test methods, but none of them was comparative. After excluding studies with overlapping patient populations, four studies investigating the alpha-defensin immunoassay and three investigating the lateral flow test remained. Alpha-defensin immunoassay studies included 482 joints and lateral flow test studies included 119. The quality of the trials was assessed according to the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. The heterogeneity among studies was evaluated by the I index, indicating that the heterogeneity of the included studies was low. Pooled sensitivity, specificity, positive and negative likelihood ratios, and receiver operating curves were calculated for each method and compared with each other. The alpha-defensin immunoassay had superior overall diagnostic value compared with the lateral flow test (area under the curve, 0.98 versus 0.75) with higher sensitivity (96% [90%-98%] versus 71% [55%-83%], p < 0.001), but no difference in specificity with the numbers available (96% [93%-97%] versus 90% [81%-95%], p = 0.060). Measurement of alpha-defensin in synovial fluid is a valuable complement to existing diagnostic criteria, and the immunoassay test detects PJI more accurately than the lateral flow test. The lateral flow test has lower sensitivity, making it difficult to rule out infection, but its relatively high specificity combined with the advantage of a quick response time can make it useful to rule in infection perioperatively. Level III, diagnostic study.
Measurement of the {sup 12}C({alpha},{gamma}){sup 16}O reaction at TRIAC
DOE Office of Scientific and Technical Information (OSTI.GOV)
Makii, H.; Miyatake, H.; Wakabayashi, Y.
2012-11-12
We have measured the {gamma}-ray angular distribution of the {sup 12}C({alpha},{gamma}){sup 16}O reaction at TRIAC (Tokai Radioactive Ion Accelerator Complex) to accurately determine the E1 and E2 cross sections. In this experiment, we used high efficiency anti-Compton NaI(T1) spectrometers to detect a {gamma}-ray from the reaction with large S/N ratio, intense pulsed {alpha}-beams to discriminate true event from background events due to neutrons from {sup 13}C({alpha},n){sup 16}O reaction with a time-of-flight (TOF) method. We succeeded in removing a background events due to neutrons and clearly detected {gamma}-ray from the {sup 12}C({alpha}{gamma}){sup 16}O reaction with high statistics.
Nakano, Sachie; Tsukimura, Takahiro; Togawa, Tadayasu; Ohashi, Toya; Kobayashi, Masahisa; Takayama, Katsuyoshi; Kobayashi, Yukuharu; Abiko, Hiroshi; Satou, Masatsugu; Nakahata, Tohru; Warnock, David G.; Sakuraba, Hitoshi; Shibasaki, Futoshi
2015-01-01
We developed an immunochromatography-based assay for detecting antibodies against recombinant α-galactosidase A proteins in serum. The evaluation of 29 serum samples from Fabry patients, who had received enzyme replacement therapy with agalsidase alpha and/or agalsidase beta, was performed by means of this assay method, and the results clearly revealed that the patients exhibited the same level of antibodies against both agalsidase alpha and agalsidase beta, regardless of the species of recombinant α-galactosidase A used for enzyme replacement therapy. A conventional enzyme-linked immunosorbent assay supported the results. Considering these, enzyme replacement therapy with agalsidase alpha or agalsidase beta would generate antibodies against the common epitopes in both agalsidase alpha and agalsidase beta. Most of the patients who showed immunopositive reaction exhibited classic Fabry phenotype and harbored gene mutations affecting biosynthesis of α-galactosidase A. As immunochromatography is a handy and simple assay system which can be available at bedside, this assay method would be extremely useful for quick evaluation or first screening of serum antibodies against agalsidase alpha or agalsidase beta in Fabry disease with enzyme replacement therapy. PMID:26083343
Automated astatination of biomolecules – a stepping stone towards multicenter clinical trials
Aneheim, Emma; Albertsson, Per; Bäck, Tom; Jensen, Holger; Palm, Stig; Lindegren, Sture
2015-01-01
To facilitate multicentre clinical studies on targeted alpha therapy, it is necessary to develop an automated, on-site procedure for conjugating rare, short-lived, alpha-emitting radionuclides to biomolecules. Astatine-211 is one of the few alpha-emitting nuclides with appropriate chemical and physical properties for use in targeted therapies for cancer. Due to the very short range of the emitted α-particles, this therapy is particularly suited to treating occult, disseminated cancers. Astatine is not intrinsically tumour-specific; therefore, it requires an appropriate tumour-specific targeting vector, which can guide the radiation to the cancer cells. Consequently, an appropriate method is required for coupling the nuclide to the vector. To increase the availability of astatine-211 radiopharmaceuticals for targeted alpha therapy, their production should be automated. Here, we present a method that combines dry distillation of astatine-211 and a synthesis module for producing radiopharmaceuticals into a process platform. This platform will standardize production of astatinated radiopharmaceuticals, and hence, it will facilitate large clinical studies focused on this promising, but chemically challenging, alpha-emitting radionuclide. In this work, we describe the process platform, and we demonstrate the production of both astaine-211, for preclinical use, and astatine-211 labelled antibodies. PMID:26169786
Tumour necrosis factor-alpha polymorphism as one of the complex inherited factors in pemphigus.
Torzecka, Jolanta Dorota; Narbutt, Joanna; Sysa-Jedrzejowska, Anna; Borowiec, Maciej; Ptasinska, Anetta; Woszczek, Grzegorz; Kowalski, Marek L
2003-01-01
The aim of our study was to analyse a significance of tumour necrosis factor (TNF)-alpha promoter gene polymorphisms in relation to the HLA-DR locus in genetic predisposition to pemphigus. TNF-alpha gene polymorphisms in position -238 and -308 were identified using a modified polymerase chain reaction-restriction fragment length polymorphism method in 53 patients with pemphigus (38 with pemphigus vulgaris, 15 with pemphigus foliaceus) and 87 healthy controls. The HLA-DRB1 locus was typed using the polymerase chain reaction SSO method in all the patients and 152 population controls. Carriers of the TNF-alpha polymorphic -308 A allele were found to be more frequent in the pemphigus foliaceus group in comparison with the control group (odds ratio (OR) = 8.12; p = 0.0005). A significant association between HLA-DRB1*04 (OR = 3.86; pcor = 0.0001) and DRB1*14 (OR = 8.4; pcor = 0.0001) and pemphigus vulgaris was found. In this group of patients a decreased frequency of HLA-DRB1*07 (OR = 0.08; pcor = 0.006) was also identified. We have shown for the first time a positive association of TNF-alpha polymorphism in position -308 with pemphigus foliaceus. PMID:14760938
Tumour necrosis factor-alpha polymorphism as one of the complex inherited factors in pemphigus.
Torzecka, Jolanta Dorota; Narbutt, Joanna; Sysa-Jedrzejowska, Anna; Borowiec, Maciej; Ptasinska, Anetta; Woszczek, Grzegorz; Kowalski, Marek L
2003-10-01
The aim of our study was to analyse a significance of tumour necrosis factor (TNF)-alpha promoter gene polymorphisms in relation to the HLA-DR locus in genetic predisposition to pemphigus. TNF-alpha gene polymorphisms in position -238 and -308 were identified using a modified polymerase chain reaction-restriction fragment length polymorphism method in 53 patients with pemphigus (38 with pemphigus vulgaris, 15 with pemphigus foliaceus) and 87 healthy controls. The HLA-DRB1 locus was typed using the polymerase chain reaction SSO method in all the patients and 152 population controls. Carriers of the TNF-alpha polymorphic -308 A allele were found to be more frequent in the pemphigus foliaceus group in comparison with the control group (odds ratio (OR) = 8.12; p = 0.0005). A significant association between HLA-DRB1*04 (OR = 3.86; pcor = 0.0001) and DRB1*14 (OR = 8.4; pcor = 0.0001) and pemphigus vulgaris was found. In this group of patients a decreased frequency of HLA-DRB1*07 (OR = 0.08; pcor = 0.006) was also identified. We have shown for the first time a positive association of TNF-alpha polymorphism in position -308 with pemphigus foliaceus.
Alpha-beta coordination method for collective search
Goldsmith, Steven Y.
2002-01-01
The present invention comprises a decentralized coordination strategy called alpha-beta coordination. The alpha-beta coordination strategy is a family of collective search methods that allow teams of communicating agents to implicitly coordinate their search activities through a division of labor based on self-selected roles and self-determined status. An agent can play one of two complementary roles. An agent in the alpha role is motivated to improve its status by exploring new regions of the search space. An agent in the beta role is also motivated to improve its status, but is conservative and tends to remain aggregated with other agents until alpha agents have clearly identified and communicated better regions of the search space. An agent can select its role dynamically based on its current status value relative to the status values of neighboring team members. Status can be determined by a function of the agent's sensor readings, and can generally be a measurement of source intensity at the agent's current location. An agent's decision cycle can comprise three sequential decision rules: (1) selection of a current role based on the evaluation of the current status data, (2) selection of a specific subset of the current data, and (3) determination of the next heading using the selected data. Variations of the decision rules produce different versions of alpha and beta behaviors that lead to different collective behavior properties.
NASA Astrophysics Data System (ADS)
van Soest, M. C.; Monteleone, B. D.; Boyce, J. W.; Hodges, K.
2009-12-01
Since its development (e.g. Zeitler et al., 1987, Lippolt et al., 1994, Farley et al., 1996, Wolf et al., 1996) as a viable low temperature thermochronological method (U-Th)/He dating of apatite has become a popular and widely applied low temperature thermochronometer. The method has been applied with success to a great variety of geological problems, and the fundamental parameters of the method: the bulk diffusion parameters of helium in apatite, and the calculated theoretical helium stopping distance in apatite used to correct the ages for the effects of alpha ejection appear sound. However, the development of the UV laser microprobe technique for the (U-Th)/He method (Boyce et al., 2006) allows for in-situ testing of the helium bulk diffusion parameters (Farley, 2000) and can provide a direct measurement of the alpha ejection distance in apatite. So, with the ultimate goal of further developing the in-situ (U-Th)/He dating method and micro-analytical depth profiling techniques to constrain cooling histories in natural grains, we conducted a helium depth profiling study of induced diffusion and natural alpha ejection profiles in Durango apatite. For the diffusion depth profiling, a Durango crystal was cut in slabs oriented parallel and perpendicular to the crystal c-axis. The slabs were polished and heated using different temperature and time schedules to induce predictable diffusion profiles based on the bulk helium diffusion parameters in apatite. Depth profiling of the 4He diffusion profiles was done using an ArF excimer laser. The measured diffusion depth profiles at 350°, 400°, and 450° C coincide well with the predicted bulk diffusion curves, independent of slab orientation, but the 300° C profiles consistently deviate significantly. The possible cause for this deviation is currently being investigated. Alpha ejection profiling was carried out on crystal margins from two different Durango apatite crystals, several faces from each crystal were analyzed to evaluate the potential effects of crystallographic orientation on alpha ejection. The results from both crystals were very reproducible irrespective of crystal surface used and confirm the findings of Monteleone et al. (2008) that the measured alpha ejection profiles deviate significantly from and are shorter than the calculated theoretical average value. Efforts are currently underway to better constrain the measured alpha ejection distance and measure alpha ejection profiles in apatite crystals other than Durango apatite. References: Boyce, J. et al. (2006) GCA 70, pp. 3031-3039. Farley, K. et al. (1996) GCA 60, pp. 4223-4229. Farley, K. (2006) JGR SE 105, p. 2903-2914. Lippolt, H. et al. (1994) Chem Geol 112, pp. 179-191. Monteleone, B. et al. (2008) Eos Trans AGU, 89 Fall Meeting V53B-2162. Wolf, R. et al. (1996) GCA 60, pp. 4231-4240. Zeitler, P. et al. (1987) GCA 51, pp. 2865-2868.
Chanton, Jeffrey P; Powelson, David K; Abichou, Tarek; Fields, Dana; Green, Roger
2008-11-01
The quantification of methane oxidation is one of the major uncertainties in estimating CH4 emissions from landfills. Stable isotope methods provide a useful field approach for the quantification of methane oxidation in landfill cover soils. The approach relies upon the difference between the isotopic composition of oxidized gas at the location of interest and anaerobic zone CH4 and knowledge of alpha(ox), a term that describes the isotopic fractionation of the methanotrophic bacteria in their discrimination against (13)CH4. Natural variability in alpha(0x) in different landfill soils and the effect of temperature and other environmental factors on this parameter are not well defined. Therefore, standard determinations of alpha(ox), batch incubations of landfill cover soils with CH4, were conducted to determine alpha(ox) under a variety of conditions. When these results were combined with those of previous landfill incubation studies, the average alpha(ox) at 25 degrees C was 1.022 +/- 0.0015. alpha(ox) decreased with increasing temperature (-0.00039 alpha(ox) degrees C(-1)) overthe temperature range of 3-35 degrees C. alpha(ox) was found to be higher when determined after CH4-free storage and declined following CH4 pretreatment. alpha(ox) declined nonlinearly with increasing methane oxidation rate, Vmax.
NASA Astrophysics Data System (ADS)
Yamamoto, Seiichi; Kawaguchi, Wataru
2018-06-01
For precise distribution measurements of alpha particles, a high-resolution alpha particle imaging detector is required. Although combining a thin scintillator with a silicon photomultiplier (Si-PM) array is a promising method for achieving high resolution, the spatial resolution is limited. Reducing the size of the Si-PM array is a possible approach to improving the spatial resolution of the alpha particle imaging detector. Consequently, we employed a 1 mm channel size Si-PM array combined with a thin ZnS(Ag) sheet to form an alpha particle imaging detector and evaluated the performance. For the developed alpha particle imaging detector, an Si-PM array with 1 mm x 1 mm channel size arranged 8 x 8 was optically coupled to a ZnS(Ag) sheet with a 1-mm-thick light guide between them. The size of the alpha particle imaging detector was 9.5 mm x 9.5 mm. The spatial resolution of the developed alpha particle imaging detector was 0.14 mm FWHM, and the energy resolution was 74% FWHM for 5.5 MeV alpha particles. The uniformity of the imaging detector at the central part of the field of view (FOV) was ±4.7%. The background count rate was 0.06 counts/min. We obtained various high-resolution phantom images for alpha particles with the developed system. We conclude that the developed imaging detector is promising for high-resolution distribution measurements of alpha particles.
Two Strategies for Microbial Production of an Industrial Enzyme-Alpha-Amylase
NASA Technical Reports Server (NTRS)
Bernhardsdotter, Eva C. M. J.; Garriott, Owen; Pusey, Marc L.; Ng, Joseph D.
2003-01-01
Extremophiles are microorganisms that thrive in, from an anthropocentric view, extreme environments including hot springs, soda lakes and arctic water. This ability of survival at extreme conditions has rendered extremophiles to be of interest in astrobiology, evolutionary biology as well as in industrial applications. Of particular interest to the biotechnology industry are the biological catalysts of the extremophiles, the extremozymes, whose unique stabilities at extreme conditions make them potential sources of novel enzymes in industrial applications. There are two major approaches to microbial enzyme production. This entails enzyme isolation directly from the natural host or creating a recombinant expression system whereby the targeted enzyme can be overexpressed in a mesophilic host. We are employing both methods in the effort to produce alpha-amylases from a hyperthermophilic archaeon (Thermococcus) isolated from a hydrothermal vent in the Atlantic Ocean, as well as from alkaliphilic bacteria (Bacillus) isolated from a soda lake in Tanzania. Alpha-amylases catalyze the hydrolysis of internal alpha-1,4-glycosidic linkages in starch to produce smaller sugars. Thermostable alpha-amylases are used in the liquefaction of starch for production of fructose and glucose syrups, whereas alpha-amylases stable at high pH have potential as detergent additives. The alpha-amylase encoding gene from Thermococcus was PCR amplified using carefully designed primers and analyzed using bioinformatics tools such as BLAST and Multiple Sequence Alignment for cloning and expression in E.coli. Four strains of Bacillus were grown in alkaline starch-enriched medium of which the culture supernatant was used as enzyme source. Amylolytic activity was detected using the starch-iodine method.
Fusion of Scores in a Detection Context Based on Alpha Integration.
Soriano, Antonio; Vergara, Luis; Ahmed, Bouziane; Salazar, Addisson
2015-09-01
We present a new method for fusing scores corresponding to different detectors (two-hypotheses case). It is based on alpha integration, which we have adapted to the detection context. Three optimization methods are presented: least mean square error, maximization of the area under the ROC curve, and minimization of the probability of error. Gradient algorithms are proposed for the three methods. Different experiments with simulated and real data are included. Simulated data consider the two-detector case to illustrate the factors influencing alpha integration and demonstrate the improvements obtained by score fusion with respect to individual detector performance. Two real data cases have been considered. In the first, multimodal biometric data have been processed. This case is representative of scenarios in which the probability of detection is to be maximized for a given probability of false alarm. The second case is the automatic analysis of electroencephalogram and electrocardiogram records with the aim of reproducing the medical expert detections of arousal during sleeping. This case is representative of scenarios in which probability of error is to be minimized. The general superior performance of alpha integration verifies the interest of optimizing the fusing parameters.
Laser scattering method applied to determine the concentration of alfa 1-antitrypsin
NASA Astrophysics Data System (ADS)
Riquelme, Bibiana D.; Foresto, Patricia; Valverde, Juana R.; Rasia, Rodolfo J.
2000-04-01
An optical method has been developed to find (alpha) 1- antitrypsin unknown concentrations in human serum samples. This method applies light scattering properties exhibited by initially formed enzyme-inhibitor complexes and uses the curves of aggregation kinetics. It is independent of molecular hydrodynamics. Theoretical approaches showed that scattering properties of transient complexes obey the Rayleigh-Debie conditions. Experiments were performed on the Trypsin/(alpha) 1-antitrypsin system. Measurements were performed in newborn, adult and pregnant sera containing (alpha) 1-antitrypsin in the Trypsin excess region. The solution was excite by a He-Ne laser beam. SO, the particles formed during the reaction are scattering centers for the interacting light. The intensity of the scattered light at 90 degrees from incident beam depends on the nature of those scattering centers. Th rate of increase in scattered intensity depends on the variation in size and shape of the scatterers, being independent of its original size. Peak values of the first derivative linearly correlate with the concentration of (alpha) 1-antitrypsin originally present in the sample. Results are displayed 5 minutes after the initiation of the experimental process. Such speed is of great importance in the immuno-biochemistry determinations.
Evaluation of maternal serum alpha-foetoprotein assay using dry blood spot samples.
González, C; Guerrero, J M; Elorza, F L; Molinero, P; Goberna, R
1988-02-01
The quantification of alpha-foetoprotein in dry blood spots from pregnant women was evaluated, using a conventional radioimmunoassay (RIA) with a monospecific antibody. The stability of alpha-foetoprotein in dry blood spots on filter paper was evaluated with respect to mailing, distances travelled, and the existence of high summer temperatures in our region. The results obtained show that the blood alpha-foetoprotein is stable on dry filter spots sent by mail and is stable for up to four weeks at 4, 25 and 37 degrees C. The analytical method used has a minimal detectable concentration of 10 +/- 1.9 international kilo-units/l. Both inter- and intra-assay variabilities are smaller than 10% and this method can provide results comparable with those of conventional serum assays. Results from dry blood spots and serum samples (the latter analysed by both RIA and two-site enzyme immunoassay) exhibited a good correlation (r = 0.98 and r = 0.97, p less than 0.001). The design of the assay and the nature of the samples make this method suitable for a screening programmes for the antenatal detection of open neural tube defects.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Habermehl, Scott D.
Described methods are useful for depositing a silicon carbide film including Alpha-SiC at low temperatures (e.g., below about 1400.degree. C.), and resulting multi-layer structures and devices. A method includes introducing a chlorinated hydrocarbon gas and a chlorosilicon gas into a reaction chamber, and reacting the chlorinated hydrocarbon gas with the chlorosilicon gas at a temperature of less than about 1400.degree. C. to grow the silicon carbide film. The silicon carbide film so-formed includes Alpha-SiC.
Cortical Alpha Activity in Schizoaffective Patients
Moeini, Mahdi; Khaleghi, Ali; Mohammadi, Mohammad Reza; Zarafshan, Hadi; Fazio, Rachel L.; Majidi, Hamid
2017-01-01
Objective: Electrophysiological studies have identified abnormal oscillatory activities in the cerebral cortex in schizophrenia and mood disorders. Biological and pathophysiological evidence suggests specific deficits in serotonin (5-HT) receptor function in schizoaffective disorder (SA), a clinical syndrome with characteristics of both schizophrenia and bipolar disorder. This study investigated alpha oscillations in patients with SA. Method: Electroencephalography was used to measure ongoing and evoked alpha oscillations in 38 adults meeting Diagnostic and Statistical Manual of Mental Disorders–Fourth Edition (DSM–IV) criteria for SA, and in 39 healthy controls. Results: Spontaneous alpha power of the participants with SA was significantly lower than that of healthy participants [F (1, 75) = 8.81, P < 0.01]. Evoked alpha activity was also decreased in SA compared to controls [F (1, 75) = 5.67, P = 0.025]. Conclusion: A strong reduction of alpha power in the posterior regions may reflect abnormality in the thalamocortical circuits. It is shown that hypoxia and reduced cerebral blood flow is associated with reduced alpha activity among different regions of the brain. Therefore, it can be concluded that greatly decreased alpha activity, particularly in centro-parietal and occipital regions, is related to SA symptoms such as hallucinations. PMID:28496495
Cortical Alpha Activity in Schizoaffective Patients.
Moeini, Mahdi; Khaleghi, Ali; Mohammadi, Mohammad Reza; Zarafshan, Hadi; Fazio, Rachel L; Majidi, Hamid
2017-01-01
Objective: Electrophysiological studies have identified abnormal oscillatory activities in the cerebral cortex in schizophrenia and mood disorders. Biological and pathophysiological evidence suggests specific deficits in serotonin (5-HT) receptor function in schizoaffective disorder (SA), a clinical syndrome with characteristics of both schizophrenia and bipolar disorder. This study investigated alpha oscillations in patients with SA. Method: Electroencephalography was used to measure ongoing and evoked alpha oscillations in 38 adults meeting Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition (DSM-IV) criteria for SA, and in 39 healthy controls. Results: Spontaneous alpha power of the participants with SA was significantly lower than that of healthy participants [F (1, 75) = 8.81, P < 0.01]. Evoked alpha activity was also decreased in SA compared to controls [F (1, 75) = 5.67, P = 0.025]. Conclusion : A strong reduction of alpha power in the posterior regions may reflect abnormality in the thalamocortical circuits. It is shown that hypoxia and reduced cerebral blood flow is associated with reduced alpha activity among different regions of the brain. Therefore, it can be concluded that greatly decreased alpha activity, particularly in centro-parietal and occipital regions, is related to SA symptoms such as hallucinations.
Evaluation of pGL1-TNF-alpha therapy in combination with radiation
NASA Technical Reports Server (NTRS)
Li, J.; Andres, M. L.; Fodor, I.; Nelson, G. A.; Gridley, D. S.
1998-01-01
Long-term control of high-grade brain tumors is rarely achieved with current therapeutic regimens. In this study a new plasmid-based human tumor necrosis factor-alpha (TNF-alpha) expression vector was synthesized (pGL1-TNF-alpha) and evaluated together with radiation in the aggressive, rapidly growing C6 rat glioma model. pGL1-TNF-alpha was successfully transfected into C6 cells in vitro using a cationic polyamine method. Expression was detected up to 7 days and averaged 0.4 ng of TNF-alpha in the culture medium from 1x10(5) cells. The expressed protein was biologically functional, as evidenced by growth inhibition of L929, a TNF-alpha-susceptible cell line. Using fluorescence-labeled monoclonal antibodies and laser scanning cytometry, we confirmed that both the P55 and P75 receptors for TNF-alpha were present on the C6 cell membrane. However, the receptors were present at low density and P55 was expressed more than the P75 receptor. These findings were in contrast to results obtained with TNF-alpha-susceptible L929 cells. Tests in athymic mice showed that pGL1-TNF-alpha administered intratumorally 16-18 h before radiation (each modality given three times) significantly inhibited C6 tumor progression (P<0.05). This effect was more than additive, because pGL1-TNF-alpha alone did not slow tumor growth and radiation alone had little effect on tumor growth. These results indicate that pGL1-TNF-alpha has potential to augment the antitumor effects of radiation against a tumor type that is virtually incurable.
Currently there are no standard radioanalytical methods applicable to the initial phase of a radiological emergency, for the early identification and quantification of alpha emitting radionuclides. Of particular interest are determinations of the presence and concentration of is...
Expression of GDNF and GFR alpha 1 in mouse taste bud cells.
Takeda, Masako; Suzuki, Yuko; Obara, Nobuko; Uchida, Nobuhiko; Kawakoshi, Kentaro
2004-11-01
GDNF (glial cell line-derived neurotrophic factor) affects the survival and maintenance of central and peripheral neurons. Using an immunocytochemical method, we examined whether the taste bud cells in the circumvallate papillae of normal mice expressed GDNF and its GFR alpha 1 receptor. Using double immunostaining for either of them and NCAM, PGP 9.5, or alpha-gustducin, we additionally sought to determine what type of taste bud cells expressed GDNF or GFR alpha 1, because NCAM is reported to be expressed in type-III cells, PGP 9.5, in type-III and some type-II cells, and alpha-gustducin, in some type-II cells. Normal taste bud cells expressed both GDNF and GFR alpha 1. The percentage of GDNF-immunoreactive cells among all taste bud cells was 31.63%, and that of GFR alpha 1-immunoreactive cells, 83.21%. Confocal laser scanning microscopic observations after double immunostaining showed that almost none of the GDNF-immunoreactive cells in the taste buds were reactive with anti-NCAM or anti-PGP 9.5 antibody, but could be stained with anti-alpha-gustducin antibody. On the other hand, almost all anti-PGP 9.5- or anti-alpha-gustducin-immunoreactive cells were positive for GFR alpha 1. Thus, GDNF-immunoreactive cells did not include type-III cells, but type-II cells, which are alpha-gustducin-immunoreactive; on the other hand, GFR alpha 1-immunoreactive cells included type-II and -III cells, and perhaps type-I cells. We conclude that GDNF in the type-II cells may exert trophic actions on type-I, -II, and -III taste bud cells by binding to their GFR alpha 1 receptors.
Uzé, G; Lutfalla, G; Bandu, M T; Proudhon, D; Mogensen, K E
1992-05-15
A murine interferon (IFN) alpha/beta receptor was cloned from the IFN-sensitive L1210 cell line on the basis of its homology with the human receptor. A combination of methods that includes the screening of random-primed and oligo(dT)-primed cDNA libraries and polymerase chain reactions with a single-side specificity was used. At the amino acid level, the murine IFN-alpha/beta shows 46% identity with its human counterpart. Both human WISH cells presenting a low sensitivity to mouse IFN and a murine L1210 mutant subline that does not express the receptor have been stably transfected with the murine IFN-alpha/beta receptor. Whereas transfected human cells became sensitive to a limited number of mouse IFN-alpha/beta subtypes, the transfected murine L1210 mutant was found to be fully complemented and became sensitive to all mouse IFN-alpha/beta subtypes tested, including those that were not active on transfected human cells. These results strongly suggest that the receptor described here is implicated in the mediation of the activities of all murine IFN-alpha/beta subtypes.
Edelstein, P H; Pasiecznik, K A; Yasui, V K; Meyer, R D
1982-01-01
Thirty-three strains of Legionella spp., 29 of which were L. pneumophila, were tested for their susceptibilities to erythromycin (EM), rosaramicin, tylosin, mycinamicin I (Sch-27897), and mycinamicin II (Sch-27896). Testing was performed using an agar dilution method with two different types of media: buffered charcoal yeast extract medium supplemented with 0.1% alpha-ketoglutarate (BCYE alpha) and filter-sterilized yeast extract medium with 0.1% alpha-ketoglutarate (BYE alpha). The minimal inhibitory concentrations (MICs) of the drugs tested relative to the MICs of erythromycin were: rosaramicin, MIC approximately equal to 0.2 EM MIC; tylosin, MIC approximately equal to 2 EM MIC; mycinamicin I, MIC approximately equal to 0.5 EM MIC; and mycinamicin II, MIC approximately equal to EM MIC. Both types of media caused equivalent partial inactivation of the macrolides which was apparently due entirely to pH effect. MICs on BCYE alpha were one to five times more than those observed on BYE alpha; this may be due to poorer growth on BYE alpha. PMID:7125633
Large Scale EOF Analysis of Climate Data
NASA Astrophysics Data System (ADS)
Prabhat, M.; Gittens, A.; Kashinath, K.; Cavanaugh, N. R.; Mahoney, M.
2016-12-01
We present a distributed approach towards extracting EOFs from 3D climate data. We implement the method in Apache Spark, and process multi-TB sized datasets on O(1000-10,000) cores. We apply this method to latitude-weighted ocean temperature data from CSFR, a 2.2 terabyte-sized data set comprising ocean and subsurface reanalysis measurements collected at 41 levels in the ocean, at 6 hour intervals over 31 years. We extract the first 100 EOFs of this full data set and compare to the EOFs computed simply on the surface temperature field. Our analyses provide evidence of Kelvin and Rossy waves and components of large-scale modes of oscillation including the ENSO and PDO that are not visible in the usual SST EOFs. Further, they provide information on the the most influential parts of the ocean, such as the thermocline, that exist below the surface. Work is ongoing to understand the factors determining the depth-varying spatial patterns observed in the EOFs. We will experiment with weighting schemes to appropriately account for the differing depths of the observations. We also plan to apply the same distributed approach to analysis of analysis of 3D atmospheric climatic data sets, including multiple variables. Because the atmosphere changes on a quicker time-scale than the ocean, we expect that the results will demonstrate an even greater advantage to computing 3D EOFs in lieu of 2D EOFs.
Yoo, Changhee; Do, Hyun-Ah; Jeong, In Gab; Park, Hongzoo; Hwang, Jung-Jin; Hong, Jun Hyuk; Cho, Jin Seon; Choo, Myong-Soo; Ahn, Hanjong; Kim, Choung-Soo
2010-09-01
Dendritic cells (DCs) are potent antigen-presenting cells. OK432 (Picibanil) was introduced as a potent stimulator of DC maturation in combination with prostaglandin-E(2) and interferon-alpha. We compared the efficacy of a DC-prostate cancer vaccine using early-mature DCs stimulated with OK432, PGE2 and INF-alpha (OPA) with that of vaccines using other methods. On days 3 or 7 of DC culture, TNF-alpha (T), TNF-alpha and LPS (TL) or OPA were employed as maturation stimulators. DU145 cells subjected to heat stress were hybridized with mature DCs using polyethyleneglycol. T cells were sensitized by the hybrids, and their proliferative and cytokine secretion activities and cytotoxicity were measured. The yields of early-mature DCs were higher, compared to yields at the conventional maturation time (P<0.05). In the early maturation setting, the mean fusion ratios, calculated from the fraction of dual-positive cells, were 13.3%, 18.6%, and 39.9%, respectively (P=0.051) in the T only, TL, and OPA-treated groups. The function of cytotoxic T cells, which were sensitized with the hybrids containing DCs matured early with OPA, was superior to that using other methods. The antitumor effects of DC-DU145 hybrids generated with DCs subjected to early maturation with the OPA may be superior to that of the hybrids using conventional maturation methods.
McDowell, W J; Farrar, D T; Billings, M R
1974-12-01
A method for the determination of uranium and plutonium by a combined high-resolution liquid scintillation-solvent extraction method is presented. Assuming a sample count equal to background count to be the detection limit, the lower detection limit for these and other alpha-emitting nuclides is 1.0 dpm with a Pyrex sample tube, 0.3 dpm with a quartz sample tube using present detector shielding or 0.02 d.p.m. with pulse-shape discrimination. Alpha-counting efficiency is 100%. With the counting data presented as an alpha-energy spectrum, an energy resolution of 0.2-0.3 MeV peak half-width and an energy identification to +/-0.1 MeV are possible. Thus, within these limits, identification and quantitative determination of a specific alpha-emitter, independent of chemical separation, are possible. The separation procedure allows greater than 98% recovery of uranium and plutonium from solution containing large amounts of iron and other interfering substances. In most cases uranium, even when present in 10(8)-fold molar ratio, may be quantitatively separated from plutonium without loss of the plutonium. Potential applications of this general analytical concept to other alpha-counting problems are noted. Special problems associated with the determination of plutonium in soil and water samples are discussed. Results of tests to determine the pulse-height and energy-resolution characteristics of several scintillators are presented. Construction of the high-resolution liquid scintillation detector is described.
Method for conversion of .beta.-hydroxy carbonyl compounds
Lilga, Michael A.; White, James F.; Holladay, Johnathan E.; Zacher, Alan H.; Muzatko, Danielle S.; Orth, Rick J.
2010-03-30
A process is disclosed for conversion of salts of .beta.-hydroxy carbonyl compounds forming useful conversion products including, e.g., .alpha.,.beta.-unsaturated carbonyl compounds and/or salts of .alpha.,.beta.-unsaturated carbonyl compounds. Conversion products find use, e.g., as feedstock and/or end-use chemicals.
Frontal alpha asymmetry and sexually motivated states.
Prause, Nicole; Staley, Cameron; Roberts, Verena
2014-03-01
Anterior alpha asymmetry of electroencephalographic (EEG) signals has been suggested to index state approach (or avoidance) motivation. This model has not yet been extended to high approach-motivation sexual stimuli, which may represent an important model of reward system function. Sixty-five participants viewed a neutral and a sexually motivating film while their EEG was recorded, and reported their sexual feelings after each film. Greater alpha power in the left hemisphere during sexually motivated states was evident. A positive relationship between self-reported mental sexual arousal and alpha asymmetry was identified, where coherence between these indicators was higher in women. Notably, coherence was stronger when mental versus physical sexual arousal was rated. Alpha asymmetry appears to offer a new method for further examining this novel coherence pattern across men and women. Copyright © 2014 Society for Psychophysiological Research.
Is Coefficient Alpha Robust to Non-Normal Data?
Sheng, Yanyan; Sheng, Zhaohui
2011-01-01
Coefficient alpha has been a widely used measure by which internal consistency reliability is assessed. In addition to essential tau-equivalence and uncorrelated errors, normality has been noted as another important assumption for alpha. Earlier work on evaluating this assumption considered either exclusively non-normal error score distributions, or limited conditions. In view of this and the availability of advanced methods for generating univariate non-normal data, Monte Carlo simulations were conducted to show that non-normal distributions for true or error scores do create problems for using alpha to estimate the internal consistency reliability. The sample coefficient alpha is affected by leptokurtic true score distributions, or skewed and/or kurtotic error score distributions. Increased sample sizes, not test lengths, help improve the accuracy, bias, or precision of using it with non-normal data. PMID:22363306
Kajiyama, Tetsuto; Kobayashi, Hisatoshi; Taguchi, Tetsushi; Kataoka, Kazunori; Tanaka, Junzo
2004-01-01
The development of synthetic biodegradable polymers, such as poly(alpha-hydroxy acid), is particularly important for constructing medical devices, including scaffolds and sutures, and has attracted growing interest in the biomedical field. Here, we report a novel approach to preparing high molecular weight poly(malic acid) (HMW--PMA) as a biodegradable and bioabsorbable water-soluble polymer. We investigated in detail the reaction conditions for the simple direct polycondensation of l-malic acid, including the reaction times, temperatures, and catalysts. The molecular weight of synthesized alpha,beta-PMA is dependent on both the reaction temperature and time. The optimum reaction condition to obtain alpha,beta-PMA by direct polycondensation using tin(II) chloride as a catalyst was thus determined to be 110 degrees C for 45 h with a molecular weight of 5300. The method for alpha,beta-PMA synthesis established here will facilitate production of alpha,beta-PMA of various molecular weights, which may have a potential utility as biomaterials.
Ray, M A; Graham, A J; Lee, M; Perry, R H; Court, J A; Perry, E K
2005-08-01
The cholinergic system has been implicated in the development of autism on the basis of neuronal nicotinic acetylcholine receptor (nAChR) losses in cerebral and cerebellar cortex. In the present study, the first to explore nAChRs in the thalamus in autism, alpha4, alpha7 and beta2 nAChR subunit expression in thalamic nuclei of adult individuals with autism (n=3) and age-matched control cases (n=3) was investigated using immunochemical methods. Loss of alpha7- and beta2- (but not alpha4-) immunoreactive neurons occurred in the paraventricular nucleus (PV) and nucleus reuniens in autism. Preliminary results indicated glutamic acid decarboxylase immunoreactivity occurred at a low level in PV, co-expressed with alpha7 in normal and autistic cases and was not reduced in autism. This suggested loss of neuronal alpha7 in autism is not caused by loss of GABAergic neurons. These findings indicate nicotinic abnormalities that occur in the thalamus in autism which may contribute to sensory or attentional deficits.
MEASUREMENTS OF AIRBORNE CONCENTRATIONS OF RADON AND THORON DECAY PRODUCTS.
Chalupnik, S; Skubacz, K; Urban, P; Wysocka, M
2017-11-01
Liquid scintillation counting (LSC) is a measuring technique, broadly applied in environmental monitoring of radionuclides. One of the possible applications of LSC is the measurement of radon and thoron decay products. But this method is suitable only for grab sampling. For long-term measurements a different technique can be applied-monitors of potential alpha energy concentration (PAEC) with thermoluminescent detectors (TLD). In these devices, called Alfa-2000 sampling probe, TL detectors (CaSO4:Dy) are applied for alpha particles counting. Three independent heads are placed over the membrane filter in a dust sampler's microcyclone. Such solution enables simultaneous measurements of PAEC and dust content. Moreover, the information which is stored in TLD chips is the energy of alpha particles, not the number of counted particles. Therefore, the readout of TL detector shows directly potential alpha energy, with no dependence on equilibrium factor, etc. This technique, which had been used only for radon decay products measurements, was modified by author to allow simultaneous measurements of radon and thoron PAEC. The LSC method can be used for calibration of portable radon decay products monitors. The LSC method has the advantage to be an absolute one, the TLD method to measure directly the (dose relevant) deposited energy. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Holmberg, H; Danielsson, D; Hardie, J; Krook, A; Whiley, R
1985-01-01
In recent years several groups have used serological methods to demonstrate pneumococcal capsular antigens in sputum. In the present study 123 strains of alpha-hemolytic streptococci (including 97 strains from sputum or pharyngeal specimens) were tested for cross-reactions with a polyvalent antipneumococcal serum (Omniserum). Representatives of the following species were included: Streptococcus bovis, S. equinus, S. intermedius, S. lactis, S. milleri, S. mitis, S. mutans, S. sobrinus, S. salivarius, S. sanguis, S. suis, and Aerococcus viridans. Serological reactions were detected by direct immunofluorescence, immunoelectroosmophoresis, and latex agglutination. Fifteen (12%) of the strains gave positive reactions by all three methods. Positive reactions were also observed with another 32 strains (26%) with two of the methods, whereas 37 strains (30%) gave positive reactions by just one technique. Altogether 84 (68%) strains gave positive reactions with one or more of the methods. Latex agglutination gave positive reactions with 26 (21%) strains compared with 57 (46%) in immunofluorescence and 63 (51%) in immunoelectroosmophoresis. Absorption of the antiserum with one alpha-hemolytic strain reduced but did not entirely eliminate the cross-reactions with five tested strains. These findings indicate a potential risk of cross-reactions with polyvalent antipneumococcal serum in tests carried out on sputa or other specimens which may be contaminated with alpha-hemolytic streptococci. PMID:3889046
Layer cathode methods of manufacturing and materials for Li-ion rechargeable batteries
Kang, Sun-Ho [Naperville, IL; Amine, Khalil [Downers Grove, IL
2008-01-01
A positive electrode active material for lithium-ion rechargeable batteries of general formula Li.sub.1+xNi.sub..alpha.Mn.sub..beta.A.sub..gamma.O.sub.2 and further wherein A is Mg, Zn, Al, Co, Ga, B, Zr, or Ti and 0
Innovative procedure for the determination of gross-alpha/gross-beta activities in drinking water.
Wisser, S; Frenzel, E; Dittmer, M
2006-03-01
An alternative sample preparation method for the determination of gross-alpha/beta activity concentrations in drinking water is introduced in this paper. After the freeze-drying of tap water samples, determination by liquid scintillation counting can be applied utilizing alpha/beta separation. It has been shown that there is no adsorption or loss of solid radionuclides during the freeze-drying procedure. However, the samples have to be measured quickly after the preparation since the ingrowth of daughter isotopes negatively effects the measurement. The limits of detection for gross-alpha and gross-beta activity are in the range 25-210 mBq/l, respectively, for a measurement time of only 8-9 h.
Solvability conditions for dendritic growth in the boundary-layer model with capillary anisotropy
NASA Technical Reports Server (NTRS)
Langer, J. S.; Hong, D. C.
1986-01-01
This paper is concerned primarily with the development of an analytic approach to the theory of steady-state velocity selection in the boundary-layer model of dendritic solidification. The two-dimensional version of this model with a fourfold crystalline anisotropy alpha in the surface tension is considered. By extending a WKB method introduced in an earlier paper, the alpha dependence of the selected growth rate is determined in the limit of small alpha; and this rate is studied for large alphas in the limit in which the dimensionless undercooling approaches unity. Portions of the paper are devoted to a reinterpretation of the mathematical structure of the solvability condition in problems of this kind.
Evaluation of a new portable glucose meter designed for the use in cats.
Zini, E; Moretti, S; Tschuor, F; Reusch, C E
2009-09-01
Portable blood glucose meters (PBGMs) are useful in the management of diabetes mellitus in cats. In the present study we compared the performance of two PBGMs: the AlphaTRAK (Abbott Animal Health, Maidenhead, England) specifically developed for dogs and cats, and the Ascensia ELITE (Bayer HealthCare, Zurich, Switzerland) developed for humans. Quality parameters, including precision and accuracy, were better for the AlphaTRAK meter compared to Ascensia ELITE. While the AlphaTRAK meter results did not differ from the reference method, results from the Ascensia ELITE were significantly (P<0.001) lower. The superior performance of the AlphaTRAK meter supports its use to monitor blood glucose levels in cats.
NASA Astrophysics Data System (ADS)
Masruri; Farid Rahman, Mohamad; Nurkam Ramadhan, Bagus
2016-02-01
Alpha-pinene was isolated in high purity from turpentine oil harvested from Pinus merkusii plantation. The recent investigation on selective oxidation of alpha-pinene using potassium permanganate was undertaken under acidic conditions. The result taught the selective oxidation of alpha-pinene in acidic using potassium permanganate lead to the formation of 2-(3-acetyl-2,2-dimethylcyclobutyl)acetaldehyde or pinon aldehyde. The study method applied reaction in various different buffer conditions i.e. pH 3, 4, 5, and 6, respectively, and each reaction product was monitored using TLC every hour. Product determination was undertaken on spectrometry basis such as infrared, ultra violet-visible, gas chromatography- and liquid chromatography-mass spectrometry.
Refined Estimates of Carbon Abundances for Carbon-Enhanced Metal-Poor Stars
NASA Astrophysics Data System (ADS)
Rossi, S.; Placco, V. M.; Beers, T. C.; Marsteller, B.; Kennedy, C. R.; Sivarani, T.; Masseron, T.; Plez, B.
2008-03-01
We present results from a refined set of procedures for estimation of the metallicities ([Fe/H]) and carbon abundance ratios ([C/Fe]) based on a much larger sample of calibration objects (on the order of 500 stars) then were available to Rossi et al. (2005), due to a dramatic increase in the number of stars with measurements obtained from high-resolution analyses in the past few years. We compare results obtained from a new calibration of the KP and GP indices with that obtained from a custom set of spectral synthesis based on MOOG. In cases where the GP index approaches saturation, it is clear that only spectral synthesis achieve reliable results.
El Montasser, Ghassen; Ajmi, Ahdi Noomen; Nguyen, Duc Khuong
2018-01-01
This article revisits the carbon dioxide (CO 2 ) emissions-GDP causal relationships in the Middle Eastern and North African (MENA) countries by employing the Rossi (Economet Theor 21:962-990, 2005) instability-robust causality test. We show evidence of significant causality relationships for all considered countries within the instability context, whereas the standard Granger causality test fails to detect causal links in any direction, except for Egypt, Iran, and Morocco. An important policy implication resulting from this robust analysis is that the income is not affected by the cuts in the CO 2 emissions for only two MENA countries, the UAE and Syria.
Millisecond Oscillations in X-ray Binaries
NASA Astrophysics Data System (ADS)
van der Klis, M.
The first millisecond X-ray variability phenomena from accreting compact objects have recently been discovered with the Rossi X-ray Timing Explorer. Three new phenomena are observed from low-mass X-ray binaries containing low-magnetic-field neutron stars: millisecond pulsations, burst oscillations, and kilohertz quasi-periodic oscillations. Models for these new phenomena involve the neutron star spin and orbital motion close around the neutron star, and rely explicitly on our understanding of strong gravity and dense matter. I review the observations of these new neutron-star phenomena and some possibly related phenomena in black-hole candidates, and describe the attempts to use these observations to perform measurements of fundamental physical interest in these systems.
NASA Astrophysics Data System (ADS)
Ovesná, Jaroslava; Demnerová, Kateřina; Pouchová, Vladimíra
Modern agriculture and the food industry are under constant pressure to produce healthier, tastier and cheaper food, while at the same time maintaining and improving safety standards. Consequently, these industries are all the time demanding still better, more efficient genotypes of crop species and farm animals suited to a wide range of usages. Farmers, in particular, are calling for species that are more resistant to disease, that have improved adaptation to stress, and that facilitate simpler farming systems while also increasing yield and productivity. At the same time, scientists believe that such animal and crop varieties could provide a source of food for poor countries and, thereby, help to prevent, and ultimately eliminate, third-world malnutrition (Biotechnology Industry Organization, 2008; Monastra & Rossi, 2003; Herdt, 2006).
2013-01-01
Background Cerebrospinal fluid (CSF) sodium concentration increases during migraine attacks, and both CSF and vitreous humor sodium increase in the rat migraine model. The Na,K-ATPase is a probable source of these sodium fluxes. Since Na,K-ATPase isoforms have different locations and physiological roles, our objective was to establish which alpha isoforms are present at sites where sodium homeostasis is disrupted. Methods Specific Na,K-ATPase alpha isoforms were identified in rat tissues by immunohistochemistry at the blood-CSF barrier at the choroid plexus, at the blood-CSF-trigeminal barrier at the meninges, at the blood-retina barrier, and at the blood-aqueous barrier at the ciliary body. Calcitonin gene-related peptide (CGRP), occludin, or von Willibrand factor (vWF) were co-localized with Na,K-ATPase to identify trigeminal nociceptor fibers, tight junctions, and capillary endothelial cells respectively. Results The Na,K-ATPase alpha-2 isoform is located on capillaries and intensely at nociceptive trigeminal nerve fibers at the meningeal blood-CSF-trigeminal barrier. Alpha-1 and −3 are lightly expressed on the trigeminal nerve fibers but not at capillaries. Alpha-2 is expressed at the blood-retina barriers and, with alpha-1, at the ciliary body blood aqueous barrier. Intense apical membrane alpha-1 was associated with moderate cytoplasmic alpha-2 expression at the choroid plexus blood-CSF barrier. Conclusion Na,K-ATPase alpha isoforms are present at the meningeal, choroid plexus, and retinal barriers. Alpha-2 predominates at the capillary endothelial cells in the meninges and retinal ganglion cell layer. PMID:23497725
Influence of pH and method of crystallization on the solid physical form of indomethacin.
Dubbini, Alessandra; Censi, Roberta; Martena, Valentina; Hoti, Ela; Ricciutelli, Massimo; Malaj, Ledjan; Di Martino, Piera
2014-10-01
The purpose of this study was to investigate the effect of pH and method of crystallization on the solid physical form of indomethacin (IDM). IDM, a non steroidal anti-inflammatory drug poorly soluble in water, underwent two different crystallization methods: crystallization by solvent evaporation under reduced pressure at 50.0°C (method A), and crystallization by cooling of solution from 50.0 to 5.0°C (method B). In both cases, several aqueous ethanolic solutions of IDM of different pHs were prepared. pHs were adjusted by adding acidic solutions (HCl 2M) or alkali (NaOH or NH4OH 2M) to an aqueous ethanolic solution of IDM. Thus, several batches were recovered after crystallization. The chemical stability of IDM was verified through (1)H NMR and mass spectroscopy (FIA-ESI-MS), that revealed that IDM degraded in strong alkali media (pH ≥ 12). Crystals obtained under different crystallization conditions at pHs of 1.0, 4.5, 7.0, 8.0, 10.0 and chemically stable were thus characterized for crystal habit by scanning electron microscopy, for thermal behaviour by differential scanning calorimetry, and thermogravimetry, and for solid state by X-ray powder diffractometry. Under the Method A, IDM always crystallized into pure metastable alpha form when solutions were acidified or alkalized respectively with HCl and NH4OH. On the contrary, in presence of NaOH, IDM crystallized under a mixture of alpha and sodium trihydrate form, because the presence of the sodium counter ion orientates the crystallization towards the formation of the trihydrate salt. Under the method B, at pH of 1.0, IDM crystallized under the alpha form; at pH 4.5, IDM crystallized under the form alpha in presence of some nuclei of gamma form; at pH 7.0, 8.0, and 10.0 for NH4OH, IDM crystallized under the most stable polymorph gamma form, whereas in presence of NaOH, a mix of alpha, and salt forms was formed whatever the pH of the solution. Copyright © 2014 Elsevier B.V. All rights reserved.
Luminescence imaging of water during alpha particle irradiation
NASA Astrophysics Data System (ADS)
Yamamoto, Seiichi; Komori, Masataka; Koyama, Shuji; Toshito, Toshiyuki
2016-05-01
The luminescence imaging of water using the alpha particle irradiation of several MeV energy range is thought to be impossible because this alpha particle energy is far below the Cerenkov-light threshold and the secondary electrons produced in this energy range do not emit Cerenkov-light. Contrary to this consensus, we found that the luminescence imaging of water was possible with 5.5 MeV alpha particle irradiation. We placed a 2 MBq of 241Am alpha source in water, and luminescence images of the source were conducted with a high-sensitivity, cooled charge-coupled device (CCD) camera. We also carried out such imaging of the alpha source in three different conditions to compare the photon productions with that of water, in air, with a plastic scintillator, and an acrylic plate. The luminescence imaging of water was observed from 10 to 20 s acquisition, and the intensity was linearly increased with time. The intensity of the luminescence with the alpha irradiation of water was 0.05% of that with the plastic scintillator, 4% with air, and 15% with the acrylic plate. The resolution of the luminescence image of water was better than 0.25 mm FWHM. Alpha particles of 5.5 MeV energy emit luminescence in water. Although the intensity of the luminescence was smaller than that in air, it was clearly observable. The luminescence of water with alpha particles would be a new method for alpha particle detection and distribution measurements in water.
Wang, Hui; Bi, Xiaohui; Xu, Lei; Li, Yirong
2017-01-01
Background Rheumatoid factor causes positive interference in multiple immunoassays. Recently, negative interference has also been found in immunoassays in the presence of rheumatoid factor. The chemiluminescent microparticle immunoassay is widely used to determine serum alpha-fetoprotein. However, it is not clear whether the presence of rheumatoid factor in the serum causes interference in the chemiluminescent microparticle immunoassay of alpha-fetoprotein. Methods Serum alpha-fetoprotein was determined using the ARCHITECT alpha-fetoprotein assay. The estimation of alpha-fetoprotein recovery was carried out in samples prepared by diluting high-concentration alpha-fetoprotein serum with rheumatoid factor-positive or rheumatoid factor-negative serum. Paramagnetic microparticles coated with hepatitis B surface antigen-anti-HBs complexes were used to remove rheumatoid factor from the serum. Results The average recovery of alpha-fetoprotein was 88.4% and 93.8% in the rheumatoid factor-positive and rheumatoid factor-negative serum samples, respectively. The recovery of alpha-fetoprotein was significantly lower in the rheumatoid factor-positive serum samples than in the rheumatoid factor-negative serum samples. In two of five rheumatoid factor-positive samples, a large difference was found (9.8%) between the average alpha-fetoprotein recoveries in the serially diluted and initial recoveries. Fourteen rheumatoid factor-positive serum samples were pretreated with hepatitis B surface antigen-anti-HBs complex-coated paramagnetic microparticles. The alpha-fetoprotein concentrations measured in the pretreated samples increased significantly. Conclusions It was concluded that the alpha-fetoprotein chemiluminescent microparticle immunoassay is susceptible to interference by rheumatoid factor, leading to significantly lower results. Eliminating the incidence of negative interference from rheumatoid factor should be an important goal for immunoassay providers. In the meantime, laboratorians must remain alert to the negative interference by rheumatoid factor, and in some cases, pretreat rheumatoid factor-positive samples with blocking or absorbing reagents.
Felger, Jennifer C.; Cole, Steve W.; Pace, Thaddeus W. W.; Hu, Fang; Woolwine, Bobbi J.; Doho, Gregory H.; Raison, Charles L.; Miller, Andrew H.
2012-01-01
Background Interferon (IFN)-alpha treatment for infectious disease and cancer causes high rates of depression and fatigue, and has been used to investigate the impact of inflammatory cytokines on brain and behavior. However, little is known about the transcriptional impact of chronic IFN-alpha on immune cells in vivo and its relationship to IFN-alpha-induced behavioral changes. Methods Genome-wide transcriptional profiling was performed on peripheral blood mononuclear cells from 21 patients with chronic hepatitis C either awaiting IFN-alpha therapy (n=10) or at 12 weeks of IFN-alpha treatment (n=11). Results Significance analysis of microarray data identified 252 up-regulated and 116 down-regulated gene transcripts. Of up-regulated genes, 2'-5'-oligoadenylate synthetase 2 (OAS2), a gene linked to chronic fatigue syndrome (CFS), was the only gene that was differentially expressed in patients with IFN-alpha-induced depression/fatigue, and correlated with depression and fatigue scores at 12 weeks (r=0.80, p=0.003 and r=0.70, p=0.017, respectively). Promoter-based bioinformatic analyses linked IFN-alpha-related transcriptional alterations to transcription factors involved in myeloid differentiation, IFN-alpha signaling, AP1 and CREB/ATF pathways, which were derived primarily from monocytes and plasmacytoid dendritic cells. IFN-alpha-treated patients with high depression/fatigue scores demonstrated up-regulation of genes bearing promoter motifs for transcription factors involved in myeloid differentiation, IFN-alpha and AP1 signaling, and reduced prevalence of motifs for CREB/ATF, which has been implicated in major depression. Conclusions Depression and fatigue during chronic IFN-alpha administration were associated with alterations in the expression (OAS2) and transcriptional control (CREB/ATF) of genes linked to behavioral disorders including CFS and major depression, further supporting an immune contribution to these diseases. PMID:22152193
Zhu, Shengming; Wang, Yanping; Zheng, Hong; Cheng, Jingqiu; Lu, Yanrong; Zeng, Yangzhi; Wang, Yu; Wang, Zhu
2009-04-01
This study sought to clone Chinese Banna minipig inbred-line (BMI) alpha1,3-galactosyltransferase (alpha1,3-GT) gene and construct its recombinant eukaryotic expression vector. Total RNA was isolated from BMI liver. Full length cDNA of alpha1,3-GT gene was amplified by RT-PCR and cloned into pMD18-T vector to sequence. Subsequently, alpha1,3-GT gene was inserted into pEGFP-N1 to construct eukaryotic expression vector pEGFP-N1-GT. Then the reconstructed plasmid pEGFP-N1-GT was transiently transfected into human lung cancer cell line A549. The expression of alpha1,3-GT mRNA in transfected cells was detected by RT-PCR. FITC-BS-IB4 lectin was used in the direct immunofluorescence method, which was performed to observe the alpha-Gal synthesis function of BMI alpha1,3-GT in transfected cells. The results showed that full length of BMI alpha1,3-GT cDNA was 1116 bp. BMI alpha1,3-GT cDNA sequence was highly homogenous with those of mouse and bovine, and was exactly the same as the complete sequence of those of swine, pEGFP-N1-GT was confirmed by enzyme digestion and PCR. The expression of alpha1,3-GT mRNA was detected in A549 cells transfected by pEGFP-N1-GT. The expression of alpha-Gal was observed on the membrane of A549 cells transfected by pEGFP-N1-GT. Successful cloning of BMI alpha1,3-GT cDNA and construction of its eukaryotic expression vector have established a foundation for further research and application of BMI alpha1,3-GT in the fields of xenotransplantation and immunological therapy of cancer.
[Studies on chemical constituents of Illicium simonsii].
Shang, Xiao-Ya; Guo, Miao-Ru; Zhao, Cong-Wei; Li, Shuai
2008-11-01
To study the chemical constituents from the active fractions against HIV in vitro, a crude ethanolic extract of Illicium simonsii. The compounds were isolated with column chromatography methods. MS and NMR spectroscopic methods were used to determine the structures of the compounds. Seven compounds were isolated from the active fractions against HIV in vitro of the 90% ethanol extract and their structures were elucidated as (+)-catechin (1), (-)-epicatechin (2), (+)-catechin 3-O-alpha-L-rhamnopyranoside (3), kaempferol 3-O-alpha-L-rhamnopyranoside (4), quercetin 3-O-alpha-L-rhamnopyranoside (5), erigeside C (6) and daucosterol (7). Seven compounds were isolated from this plant for the first time, but none of them exhibited active against HIV in vitro. Compounds 3 and 6 were isolated from this genus for the first time.
Assault frequency and preformation probability of the {alpha} emission process
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, H. F.; Royer, G.; Li, J. Q.
2011-08-15
A study of the assault frequency and preformation factor of the {alpha}-decay description is performed from the experimental {alpha}-decay constant and the penetration probabilities calculated from the generalized liquid-drop model (GLDM) potential barriers. To determine the assault frequency a quantum-mechanical method using a harmonic oscillator is introduced and leads to values of around 10{sup 21} s{sup -1}, similar to the ones calculated within the classical method. The preformation probability is around 10{sup -1}-10{sup -2}. The results for even-even Po isotopes are discussed for illustration. While the assault frequency presents only a shallow minimum in the vicinity of the magic neutronmore » number 126, the preformation factor and mainly the penetrability probability diminish strongly around N=126.« less
Electronic Properties of DNA-Based Schottky Barrier Diodes in Response to Alpha Particles.
Al-Ta'ii, Hassan Maktuff Jaber; Periasamy, Vengadesh; Amin, Yusoff Mohd
2015-05-21
Detection of nuclear radiation such as alpha particles has become an important field of research in recent history due to nuclear threats and accidents. In this context; deoxyribonucleic acid (DNA) acting as an organic semiconducting material could be utilized in a metal/semiconductor Schottky junction for detecting alpha particles. In this work we demonstrate for the first time the effect of alpha irradiation on an Al/DNA/p-Si/Al Schottky diode by investigating its current-voltage characteristics. The diodes were exposed for different periods (0-20 min) of irradiation. Various diode parameters such as ideality factor, barrier height, series resistance, Richardson constant and saturation current were then determined using conventional, Cheung and Cheung's and Norde methods. Generally, ideality factor or n values were observed to be greater than unity, which indicates the influence of some other current transport mechanism besides thermionic processes. Results indicated ideality factor variation between 9.97 and 9.57 for irradiation times between the ranges 0 to 20 min. Increase in the series resistance with increase in irradiation time was also observed when calculated using conventional and Cheung and Cheung's methods. These responses demonstrate that changes in the electrical characteristics of the metal-semiconductor-metal diode could be further utilized as sensing elements to detect alpha particles.
BOOTSTRAPPING THE CORONAL MAGNETIC FIELD WITH STEREO: UNIPOLAR POTENTIAL FIELD MODELING
DOE Office of Scientific and Technical Information (OSTI.GOV)
Aschwanden, Markus J.; Sandman, Anne W., E-mail: aschwanden@lmsal.co
We investigate the recently quantified misalignment of {alpha}{sub mis} {approx} 20{sup 0}-40{sup 0} between the three-dimensional geometry of stereoscopically triangulated coronal loops observed with STEREO/EUVI (in four active regions (ARs)) and theoretical (potential or nonlinear force-free) magnetic field models extrapolated from photospheric magnetograms. We develop an efficient method of bootstrapping the coronal magnetic field by forward fitting a parameterized potential field model to the STEREO-observed loops. The potential field model consists of a number of unipolar magnetic charges that are parameterized by decomposing a photospheric magnetogram from the Michelson Doppler Imager. The forward-fitting method yields a best-fit magnetic field modelmore » with a reduced misalignment of {alpha}{sub PF} {approx} 13{sup 0}-20{sup 0}. We also evaluate stereoscopic measurement errors and find a contribution of {alpha}{sub SE} {approx} 7{sup 0}-12{sup 0}, which constrains the residual misalignment to {alpha}{sub NP} {approx} 11{sup 0}-17{sup 0}, which is likely due to the nonpotentiality of the ARs. The residual misalignment angle, {alpha}{sub NP}, of the potential field due to nonpotentiality is found to correlate with the soft X-ray flux of the AR, which implies a relationship between electric currents and plasma heating.« less
Mccleary, Barry V
2014-01-01
AOAC Official Methods 2009.01 and 2011.25 have been modified to allow removal of resistant maltodextrins produced on hydrolysis of various starches by the combination of pancreatic alpha-amylase and amyloglucosidase (AMG) used in these assay procedures. The major resistant maltodextrin, 6(3),6(5)-di-alpha-D-glucosyl maltopentaose, is highly resistant to hydrolysis by microbial alpha-glucosidases, isoamylase, pullulanase, pancreatic, bacterial and fungal alpha-amylase and AMG. However, this oligosaccharide is hydrolyzed by the mucosal alpha-glucosidase complex of the pig small intestine (which is similar to the human small intestine), and thus must be removed in the analytical procedure. Hydrolysis of these oligosaccharides has been by incubation with a high concentration of a purified AMG at 60 degrees C. This incubation results in no hydrolysis or loss of other resistant oligosaccharides such as FOS, GOS, XOS, resistant maltodextrins (e.g., Fibersol 2) or polydextrose. The effect of this additional incubation with AMG on the measured level of low molecular weight soluble dietary fiber (SDFS) and of total dietary fiber in a broad range of samples is reported. Results from this study demonstrate that the proposed modification can be used with confidence in the measurement of dietary fiber.
Kim, Sung-Jo
2010-06-01
In addition to regulating body weight, leptin is also recognized for its role in the regulation of immune function and inflammation. The purpose of this study was to investigate the effect of leptin on Prevotella (P.) intermedia lipopolysaccharide (LPS)-induced tumor necrosis factor (TNF)-alpha production in differentiated THP-1 cells, a human monocytic cell line. LPS from P. intermedia ATCC 25611 was prepared by the standard hot phenol-water method. THP-1 cells were incubated in the medium supplemented with phorbol myristate acetate to induce differentiation into macrophage-like cells. The amount of TNF-alpha and interleukin-8 secreted into the culture medium was determined by enzyme-linked immunosorbent assay (ELISA). TNF-alpha and Ob-R mRNA expression levels were determined by semi-quantitative reverse transcription-polymerase chain reaction analysis. Leptin enhanced P. intermedia LPS-induced TNF-alpha production in a dose-dependent manner. Leptin modulated P. intermedia LPS-induced TNF-alpha expression predominantly at the transcriptional level. Effect of leptin on P. intermedia LPS-induced TNF-alpha production was not mediated by the leptin receptor. The ability of leptin to enhance P. intermedia LPS-induced TNF-alpha production may be important in the establishment of chronic lesion accompanied by osseous tissue destruction observed in inflammatory periodontal disease.
Cohen, A B; Gruenke, L D; Craig, J C; Geczy, D
1977-01-01
alpha-1-Antitrypsin is a serum protein that inhibits many proteolytic enzymes. Recently, it was suggested that the alpha-1-antitrypsin-trypsin complex is an acyl ester analogous to the acyl intermediate that forms between trypsin and its substrates. In previous work we showed that the alpha-1-antitrypsin-trypsin complex can be split at high pH, releasing a component of alpha-1-antitrypsin. This component had a new carboxyl-terminal lysine, and it had lost a peptide of about 4000 daltons. In order to determine whether the alpha-1-antitrypsin is bound to trypsin through the new carboxy-terminal lysine, as would be expected if the above hypothesis is correct, we split the complex in the presence of 18OH-. When the new carboxy-terminal lysine was cleaved with carboxypeptidase B, singly labeled, doubly labeled, and unlabeled lysine were recovered. These data support the hypothesis that the alpha-1-antitrypsin-trypsin complex is an acyl ester or a tetrahedral precursor that is transformed into the acyl ester form at high pH. If other enzymes are bound by a similar mechanism, the methods used may be useful in determining which amino acids on alpha-1-antitrypsin bind covalently to each enzyme. PMID:303770
Liu, B; Zhang, Q; Li, Y
1997-12-01
This paper introduces a method to determine the volume activity concentration of alpha and/or beta artificial radionuclides in the environment and radon/thoron progeny background-compensation based on a Si surface-barrier detector. By measuring the alpha peak counts of 218Po and 214Po in two time intervals, the activity concentration of 218Po, 214Pb and 214Bi aerosol particles were determined; meanwhile, the total beta count of 214Pb and 214Bi aerosols was also calculated from their decay scheme. With the average equilibrium factor of thoron progeny in general environment, the alpha and beta counts of thoron progeny were approximately evaluated by 212Po alpha peak counts. The alpha count of transuranic aerosols was determined by subtracting the trail counts of radon/thoron progeny alpha peaks. The total count of beta artificial radionuclides was determined by subtracting the beta counts of radon/thoron progeny aerosol particles. In our preliminary experiments, if the radon progeny concentration is less than 15 Bq m(-3), the lower limit of detection of transuranics concentration is less than 0.1 Bq m(-3). Even if the radon progeny concentration is as high as 75 Bq m(-3), the lower limit of detection of total beta activity concentration of artificial nuclides aerosols is less than 1 Bq m(-3).
In situ temperature measurement of. alpha. -mercuric iodide by reflection spectroscopy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nason, D.; Burger, A.
1991-12-30
Crystal face temperatures of single crystals of {alpha}-HgI{sub 2} growing in transparent ampules by physical vapor transport have been measured, {ital in} {ital situ}, by a novel, noncontact method which may be called reflectance spectroscopy thermometry. The method is based on the temperature dependence of the energy of the free-exciton peak as detected with a low-energy reflected beam. As presently configured, the accuracy is {plus minus}1.5 {degree}C for a slowly varying surface temperature. The method has potential for noncontact temperature measurement in some systems for which pyrometry is unsatisfactory.
Synthesis of alpha-amino acids
Davis, Jr., Jefferson W.
1983-01-01
A method for synthesizing alpha amino acids proceeding through novel intermediates of the formulas: R.sub.1 R.sub.2 C(OSOCl)CN, R.sub.1 R.sub.2 C(Cl)CN and [R.sub.1 R.sub.2 C(CN)O].sub.2 SO wherein R.sub.1 and R.sub.2 are each selected from hydrogen monovalent substituted and unsubstituted hydrocarbon radicals of 1 to 12 carbon atoms. The use of these intermediates allows the synthesis steps to be exothermic and results in an overall synthesis method which is faster than the synthesis methods of the prior art.
Synthesis of alpha-amino acids
Davis, J.W. Jr.
1983-01-25
A method is described for synthesizing alpha amino acids proceeding through novel intermediates of the formulas: R[sub 1]R[sub 2]C(OSOCl)CN, R[sub 1]R[sub 2]C(Cl)CN and [R[sub 1]R[sub 2]C(CN)O][sub 2]SO wherein R[sub 1] and R[sub 2] are each selected from hydrogen monovalent substituted and unsubstituted hydrocarbon radicals of 1 to 10 carbon atoms. The use of these intermediates allows the synthesis steps to be exothermic and results in an overall synthesis method which is faster than the synthesis methods of the prior art. No Drawings
Synthesis of alpha-amino acids
Davis, Jr., Jefferson W.
1983-01-01
A method for synthesizing alpha amino acids proceding through novel intermediates of the formulas: R.sub.1 R.sub.2 C(OSOCl)CN, R.sub.1 R.sub.2 C(Cl)CN and [R.sub.1 R.sub.2 C(CN)O].sub.2 SO wherein R.sub.1 and R.sub.2 are each selected from hydrogen monovalent substituted and unsubstituted hydrocarbon radicals of 1 to 10 carbon atoms. The use of these intermediates allows the synthesis steps to be exothermic and results in an overall synthesis method which is faster than the snythesis methods of the prior art.
Synthesis of alpha-amino acids
Davis, Jr., Jefferson W.
1983-01-01
A method for synthesizing alpha amino acids proceding through novel intermediates of the formulas: R.sub.1 R.sub.2 C(OSOCl)CN, R.sub.1 R.sub.2 C(Cl)CN and [R.sub.1 R.sub.2 C(CN)O].sub.2 SO wherein R.sub.1 and R.sub.2 are each selected from hydrogen monovalent substituted and unsubstituted hydrocarbon radicals of 1 to 12 carbon atoms. The use of these intermediates allows the synthesis steps to be exothermic and results in an overall synthesis method which is faster than the synthesis methods of the prior art.
Bell, Iris R.; Brooks, Audrey J.; Howerter, Amy; Jackson, Nicholas; Schwartz, Gary E.
2011-01-01
Introduction Homeopathic pathogenetic trials usually rely on symptom self report measures. Adding objective biomarkers could enhance detection of subtle initial remedy effects. The present feasibility study examined electroencephalographic (EEG) effects of repeated olfactory administration of two polycrest remedies. Methods College student volunteers (ages 18–30, both sexes) from an introductory psychology course were screened for good health and relatively elevated Sulphur OR Pulsatilla symptom scores on the Homeopathic Constitutional Type Questionnaire. Subjects underwent a series of 3 once-weekly double-blind sessions during which they repeatedly sniffed the remedy matched to their CTQ type and solvent controls. Each remedy was given in a 6c, 12c, and 30c potency, one potency per week, in randomly assigned order. Solvent controls included both plain distilled water and a water-ethanol (95%) solution. All sniff test solutions were further diluted just prior to laboratory sessions (0.5 ml test solution in 150 ml distilled water). Within a session, remedies and control solvents were administered via 2-second sniffs (8 sniffs of each of 4 different succussion levels for the potency in randomized order). Primary outcome variable was relative EEG power (alpha 1 8–10 hertz; alpha 2 10–12 hertz) averaged over 19 electrode sites, including all succussions for a given potency. Results Mixed-effect models revealed significant main effects for remedy type (Sulphur>Pulsatilla) in both alpha bands, controlling for gender, baseline resting EEG alpha, and solvent control responses. Additional analyses showed significant non-linear interactions between dilution and time (weekly session) in alpha 2 for both remedies and alpha 1 for Sulphur. Conclusion EEG alpha offers an objective biomarker of remedy effects for future studies and potential method for distinguishing time-dependent effects of specific remedies and remedy potencies from one another. PMID:21962194
Engl, Tobias; Makarević, Jasmina; Relja, Borna; Natsheh, Iyad; Müller, Iris; Beecken, Wolf-Dietrich; Jonas, Dietger; Blaheta, Roman A
2005-01-01
Background Tumor development remains one of the major obstacles following organ transplantation. Immunosuppressive drugs such as cyclosporine and tacrolimus directly contribute to enhanced malignancy, whereas the influence of the novel compound mycophenolate mofetil (MMF) on tumor cell dissemination has not been explored. We therefore investigated the adhesion capacity of colon, pancreas, prostate and kidney carcinoma cell lines to endothelium, as well as their beta1 integrin expression profile before and after MMF treatment. Methods Tumor cell adhesion to endothelial cell monolayers was evaluated in the presence of 0.1 and 1 μM MMF and compared to unstimulated controls. beta1 integrin analysis included alpha1beta1 (CD49a), alpha2beta1 (CD49b), alpha3beta1 (CD49c), alpha4beta1 (CD49d), alpha5beta1 (CD49e), and alpha6beta1 (CD49f) receptors, and was carried out by reverse transcriptase-polymerase chain reaction, confocal microscopy and flow cytometry. Results Adhesion of the colon carcinoma cell line HT-29 was strongly reduced in the presence of 0.1 μM MMF. This effect was accompanied by down-regulation of alpha3beta1 and alpha6beta1 surface expression and of alpha3beta1 and alpha6beta1 coding mRNA. Adhesion of the prostate tumor cell line DU-145 was blocked dose-dependently by MMF. In contrast to MMF's effects on HT-29 cells, MMF dose-dependently up-regulated alpha1beta1, alpha2beta1, alpha3beta1, and alpha5beta1 on DU-145 tumor cell membranes. Conclusion We conclude that MMF possesses distinct anti-tumoral properties, particularly in colon and prostate carcinoma cells. Adhesion blockage of HT-29 cells was due to the loss of alpha3beta1 and alpha6beta1 surface expression, which might contribute to a reduced invasive behaviour of this tumor entity. The enhancement of integrin beta1 subtypes observed in DU-145 cells possibly causes re-differentiation towards a low-invasive phenotype. PMID:15644133
Termination of pregnancy by extraamniotic prostaglandins and the synergistic action of oxytocin.
Embrey, M P; Hillier, K; Mahendran, P
1973-01-01
This study determines the efficacy of extraamniotic administration of prostaglandins E2 and F2alpha (PGE2 and PGF2alpha) in abortion induction. The method consists of introducing a Foley catheter (14 gauge) through the cervix with the aid of a speculum so that the inflated balloon lies just within the internal os. The balloon volume varies from 30 ml at 12 weeks to 40 ml at 16 weeks gestation and over. Following an initial test dose, a fully effective dose of 200 mcg PGE2 or 750 mcg PGF2alpha is instilled for diffusion into the extraovular space; this dose is repeated at 2 hourly intervals. An automatic pump may also be used to administer the PG. The pattern of uterine contractility with this method is similar to that seen with intravenous therapy. Of 163 consecutive cases analyzed, 144 (88%) achieved abortions within 36 hours, 72% aborted within 24 hours and 94% within 48 hours. Mean abortion time was 22.2 hours. No significant difference was seen in the success rate or abortion time between 21 patients in their 1st trimester of pregnancy and 142 patients in the 2nd trimester. In primigravidas, abortion (within 36 hours) was successful in 87% of the cases; mean abortion time was 24.0 hours. Multigravidas had higher success rate (90%) and shorter mean abortion time (20.4 hours). Comparison of results obtained separately with PGF2alpha and PGE2 shows the superiority of PGE2. Of 93 patients receiving PGF2alpha, 85% aborted within 36 hours (mean abortion time, 24.9 hours). Of 70 PGE2-treated patients, 93% aborted within 36 hours (p=.01) (mean abortion time, 19.4 hours). When parity was considered, PGE2 came out superior again over PGF2alpha. In primigravidas, only 84% of PGF2alpha-treated patients had abortion within 36 hours compared to 90% for PGE2-treated patients. In multigravidas, the success rates at 36 hours were 86% for PGF2alpha and 95% for PGE2. Side effects were minimal. In another trial, intravenous oxytocin was used in addition to extraamniotic PG, resulting in a very substantial decrease in mean abortion time. This method is a simple, effective abortion technique which can be carried out in most cases on a 24-hour basis.
NASA Technical Reports Server (NTRS)
Chiu, Y. T.; Hilton, H. H.
1977-01-01
Exact closed-form solutions to the solar force-free magnetic-field boundary-value problem are obtained for constant alpha in Cartesian geometry by a Green's function approach. The uniqueness of the physical problem is discussed. Application of the exact results to practical solar magnetic-field calculations is free of series truncation errors and is at least as economical as the approximate methods currently in use. Results of some test cases are presented.
NASA Astrophysics Data System (ADS)
Daftardar-Gejji, Varsha; Jafari, Hossein
2005-01-01
Adomian decomposition method has been employed to obtain solutions of a system of fractional differential equations. Convergence of the method has been discussed with some illustrative examples. In particular, for the initial value problem: where A=[aij] is a real square matrix, the solution turns out to be , where E([alpha]1,...,[alpha]n),1 denotes multivariate Mittag-Leffler function defined for matrix arguments and Ai is the matrix having ith row as [ai1...ain], and all other entries are zero. Fractional oscillation and Bagley-Torvik equations are solved as illustrative examples.
Role of IL-10 -1082, IFN-gamma +874, and TNF-alpha -308 genes polymorphisms in suicidal behavior.
Omrani, Mir Davood; Bushehri, Behzad; Bagheri, Morteza; Salari-Lak, Shaker; Alipour, Azize; Anoshae, Mohamad-Reza; Massomi, Reza
2009-01-01
In this study, it was determined whether the IL-10 -1082, IFN-gamma +874, and TNF-alpha -308 polymorphisms were associated with suicidal behavior. One hundred forty five patients with suicidal behavior and 160 normal individuals were genotyped for IL-10 -1082, IFN-gamma +874, and TNF-alpha -308 polymorphisms using ASO-PCR method. TNF-alpha -308 G/G genotype has been increased in males with completed suicide behavior versus control group (p value = 0.017). IL-10 -1082 A/A genotype is higher in both male and female suicide completed groups (p value = 0.017). IFN-gamma (+874) A/A genotype was significantly higher in males with completed suicide behavior versus normal male control (p value = 0.027). It can be concluded that IL-10, IFN-gamma, and TNF-alpha polymorphisms may play a role in suicidal behavior.
Nemoto, Tetsuhiro; Kakei, Hiroyuki; Gnanadesikan, Vijay; Tosaki, Shin-Ya; Ohshima, Takashi; Shibasaki, Masakatsu
2002-12-11
The catalytic asymmetric epoxidation of alpha,beta-unsaturated amides using Sm-BINOL-Ph3As=O complex was succeeded. Using 5-10 mol % of the asymmetric catalyst, a variety of amides were epoxidized efficiently, yielding the corresponding alpha,beta-epoxy amides in up to 99% yield and in more than 99% ee. Moreover, the novel one-pot tandem process, one-pot tandem catalytic asymmetric epoxidation-Pd-catalyzed epoxide opening process, was developed. This method was successfully utilized for the efficient synthesis of beta-aryl alpha-hydroxy amides, including beta-aryllactyl-leucine methyl esters. Interestingly, it was found that beneficial modifications on the Pd catalyst were achieved by the constituents of the first epoxidation, producing a more suitable catalyst for the Pd-catalyzed epoxide opening reaction in terms of chemoselectivity.
Investigation of the triple-α reaction in a full three-body approach
Nguyen, N. B.; Nunes, F. M.; Thompson, I. J.
2013-05-22
Here, the triple-alpha reaction is the key to our understanding about the nucleosynthesis and the observed abundance of 12C in stars. The theory of this process is well established at high temperatures but rather ambiguous in the low temperature regime where measurements are impossible. Develop a new three-body method, which tackles properly the scattering boundary condition for three charged particles and takes into account both the resonant and the non-resonant reaction mechanisms on the same footing, to compute the triple-alpha reaction rate at low temperatures. Methods: We combine the R-matrix expansion, the R-matrix propagation method, and the screening technique inmore » the hyperspherical harmonics basis. Both the 2 + 1 bound state and the 0 + 2 resonant state in 12C are well reproduced. We also study the cluster structure of these states. We calculate the triple-alpha reaction rate for T = 0.01 - 0.1 GK. In conclusion, we obtain the same rate as NACRE for temperatures above 0.07 GK, but the new rate is largely enhanced at lower temperatures (≈ 10 12 at 0.02 GK). The differences are caused by the direct capture contribution to the reaction when three alpha particles can not reach the resonant energies.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Xu, Yanni; Lai, Fangfang; Xu, Yang
2011-11-04
Highlights: Black-Right-Pointing-Pointer Using an ABCA1p-LUC HepG2 cell line, we found that MPA upregulated ABCA1 expression. Black-Right-Pointing-Pointer MPA induced ABCA1 and LXR{alpha} protein expression in HepG2 cells. Black-Right-Pointing-Pointer PPAR{gamma} antagonist GW9662 markedly inhibited MPA-induced ABCA1 and LXR{alpha} protein expression. Black-Right-Pointing-Pointer The effect of MPA upregulating ABCA1 was due mainly to activation of the PPAR{gamma}-LXR{alpha}-ABCA1 pathway. -- Abstract: ATP-binding cassette transporter A1 (ABCA1) promotes cholesterol and phospholipid efflux from cells to lipid-poor apolipoprotein A-I and plays an important role in atherosclerosis. In a previous study, we developed a high-throughput screening method using an ABCA1p-LUC HepG2 cell line to find upregulators of ABCA1.more » Using this method in the present study, we found that mycophenolic acid (MPA) upregulated ABCA1 expression (EC50 = 0.09 {mu}M). MPA upregulation of ABCA1 expression was confirmed by real-time quantitative reverse transcription-PCR and Western blot analysis in HepG2 cells. Previous work has indicated that MPA is a potent agonist of peroxisome proliferator-activated receptor gamma (PPAR{gamma}; EC50 = 5.2-9.3 {mu}M). Liver X receptor {alpha} (LXR{alpha}) is a target gene of PPAR{gamma} and may directly regulate ABCA1 expression. Western blot analysis showed that MPA induced LXR{alpha} protein expression in HepG2 cells. Addition of PPAR{gamma} antagonist GW9662 markedly inhibited MPA-induced ABCA1 and LXR{alpha} protein expression. These data suggest that MPA increased ABCA1 expression mainly through activation of PPAR{gamma}. Thus, the effects of MPA on upregulation of ABCA1 expression were due mainly to activation of the PPAR{gamma}-LXR{alpha}-ABCA1 signaling pathway. This is the first report that the antiatherosclerosis activity of MPA is due to this mechanism.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vogelius, Ivan R., E-mail: vogelius@gmail.com; Bentzen, Soren M.
Purpose: To present a novel method for meta-analysis of the fractionation sensitivity of tumors as applied to prostate cancer in the presence of an overall time factor. Methods and Materials: A systematic search for radiation dose-fractionation trials in prostate cancer was performed using PubMed and by manual search. Published trials comparing standard fractionated external beam radiation therapy with alternative fractionation were eligible. For each trial the {alpha}/{beta} ratio and its 95% confidence interval (CI) were extracted, and the data were synthesized with each study weighted by the inverse variance. An overall time factor was included in the analysis, and itsmore » influence on {alpha}/{beta} was investigated. Results: Five studies involving 1965 patients were included in the meta-analysis of {alpha}/{beta}. The synthesized {alpha}/{beta} assuming no effect of overall treatment time was -0.07 Gy (95% CI -0.73-0.59), which was increased to 0.47 Gy (95% CI -0.55-1.50) if a single highly weighted study was excluded. In a separate analysis, 2 studies based on 10,808 patients in total allowed extraction of a synthesized estimate of a time factor of 0.31 Gy/d (95% CI 0.20-0.42). The time factor increased the {alpha}/{beta} estimate to 0.58 Gy (95% CI -0.53-1.69)/1.93 Gy (95% CI -0.27-4.14) with/without the heavily weighted study. An analysis of the uncertainty of the {alpha}/{beta} estimate showed a loss of information when the hypofractionated arm was underdosed compared with the normo-fractionated arm. Conclusions: The current external beam fractionation studies are consistent with a very low {alpha}/{beta} ratio for prostate cancer, although the CIs include {alpha}/{beta} ratios up to 4.14 Gy in the presence of a time factor. Details of the dose fractionation in the 2 trial arms have critical influence on the information that can be extracted from a study. Studies with unfortunate designs will supply little or no information about {alpha}/{beta} regardless of the number of subjects enrolled.« less
Abe, Masayuki; Ito, Yoshihiko; Oyunzul, Luvsandorj; Oki-Fujino, Tomomi; Yamada, Shizuo
2009-04-01
Saw palmetto extract (SPE), used widely for the treatment of benign prostatic hyperplasia (BPH) has been shown to bind alpha(1)-adrenergic, muscarinic and 1,4-dihydropyridine (1,4-DHP) calcium channel antagonist receptors. Major constituents of SPE are lauric acid, oleic acid, myristic acid, palmitic acid and linoleic acid. The aim of this study was to investigate binding affinities of these fatty acids for pharmacologically relevant (alpha(1)-adrenergic, muscarinic and 1,4-DHP) receptors. The fatty acids inhibited specific [(3)H]prazosin binding in rat brain in a concentration-dependent manner with IC(50) values of 23.8 to 136 microg/ml, and specific (+)-[(3)H]PN 200-110 binding with IC(50) values of 24.5 to 79.5 microg/ml. Also, lauric acid, oleic acid, myristic acid and linoleic acid inhibited specific [(3)H]N-methylscopolamine ([(3)H]NMS) binding in rat brain with IC(50) values of 56.4 to 169 microg/ml. Palmitic acid had no effect on specific [(3)H]NMS binding. The affinity of oleic acid, myristic acid and linoleic acid for each receptor was greater than the affinity of SPE. Scatchard analysis revealed that oleic acid and lauric acid caused a significant decrease in the maximal number of binding sites (B(max)) for [(3)H]prazosin, [(3)H]NMS and (+)-[(3)H]PN 200-110. The results suggest that lauric acid and oleic acid bind noncompetitively to alpha(1)-adrenergic, muscarinic and 1,4-DHP calcium channel antagonist receptors. We developed a novel and convenient method of determining 5alpha-reductase activity using LC/MS. With this method, SPE was shown to inhibit 5alpha-reductase activity in rat liver with an IC(50) of 101 microg/ml. Similarly, all the fatty acids except palmitic acid inhibited 5alpha-reductase activity, with IC(50) values of 42.1 to 67.6 microg/ml. In conclusion, lauric acid, oleic acid, myristic acid, and linoleic acid, major constituents of SPE, exerted binding activities of alpha(1)-adrenergic, muscarinic and 1,4-DHP receptors and inhibited 5alpha-reductase activity.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen Yuhchyau; Hyrien, Ollivier; Williams, Jacqueline
2005-05-01
Purpose: To explore the application of interleukin (IL)-1{alpha} and IL-6 measurements in the predictive diagnostic testing for symptomatic radiation pneumonitis (RP). Methods and materials: In a prospective protocol investigating RP and cytokines, IL-1{alpha} and IL-6 values were analyzed by enzyme-linked immunosorbent assay from serial weekly blood samples of patients receiving chest radiation. We analyzed sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) over selected threshold values for both cytokines in the application to diagnostic testing. Results: The average coefficient of variation was 51% of the weekly mean IL-1{alpha} level and 39% of the weekly mean IL-6 value.more » Interleukin 1{alpha} and IL-6 became positively correlated with time. Specificity for both cytokines was better than sensitivity. IL-6 globally outperformed IL-1{alpha} in predicting RP, with higher PPV and NPV. Conclusions: Our data demonstrate the feasibility of applying IL-1{alpha} and IL-6 measurements of blood specimens to predict RP. Interleukin-6 measurements offer stronger positive predictive value than IL-1{alpha}. This application might be further explored in a larger sample of patients.« less
Uzé, G; Lutfalla, G; Bandu, M T; Proudhon, D; Mogensen, K E
1992-01-01
A murine interferon (IFN) alpha/beta receptor was cloned from the IFN-sensitive L1210 cell line on the basis of its homology with the human receptor. A combination of methods that includes the screening of random-primed and oligo(dT)-primed cDNA libraries and polymerase chain reactions with a single-side specificity was used. At the amino acid level, the murine IFN-alpha/beta shows 46% identity with its human counterpart. Both human WISH cells presenting a low sensitivity to mouse IFN and a murine L1210 mutant subline that does not express the receptor have been stably transfected with the murine IFN-alpha/beta receptor. Whereas transfected human cells became sensitive to a limited number of mouse IFN-alpha/beta subtypes, the transfected murine L1210 mutant was found to be fully complemented and became sensitive to all mouse IFN-alpha/beta subtypes tested, including those that were not active on transfected human cells. These results strongly suggest that the receptor described here is implicated in the mediation of the activities of all murine IFN-alpha/beta subtypes. Images PMID:1533935
Ultra-Performance Liquid Chromatographic Determination of Tocopherols and Retinol in Human Plasma
Bell, Edward C.; John, Mathew; Hughes, Rodney J.; Pham, Thu
2014-01-01
A rapid, selective and sensitive ultra-performance liquid chromatography method has been developed for the detection and quantification of tocopherols and retinol in human plasma. Alpha-tocopherol, gamma-tocopherol and retinol are assayed using fluorescence detection. Excitation/emission wavelengths are 295/330 nm and 325/470 nm for the analysis of both tocopherols and retinol, respectively. Retinol acetate is employed as the internal standard. The reversed-phase method incorporates gradient elution with a mobile phase consisting of methanol and acetonitrile. Separation of vitamin compounds is achieved using a bridged ethyl hybrid C18 column. The retention times for retinol, retinol acetate, gamma-tocopherol and alpha-tocopherol are 1.6, 1.8, 3.9 and 4.3 min, respectively. The limits of quantification for retinol, gamma-tocopherol and alpha-tocopherol were 0.02, 0.02 and 0.1 µg/mL, respectively. The assay method is suitable for the analysis of tocopherols and retinol in human plasma. The method may be applied following the ingestion of foods fortified with these fat-soluble vitamins. PMID:24170122
DOE Office of Scientific and Technical Information (OSTI.GOV)
Orazov, Marat; Davis, Mark E.
The present disclosure is directed to methods and composition used in the preparation of alpha-hydroxy carboxylic acids and esters from higher sugars using a tandem catalyst system comprising retro-aldol catalysts and Lewis acid catalysts. In some embodiments, these alpha-hydroxy carboxylic acids may be prepared from pentoses and hexoses. The retro-aldol and Lewis catalysts may be characterized by their respective ability to catalyze a 1,2-carbon shift reaction and a 1,2-hydride shift reaction on an aldose or ketose substrate.
Relativistic scattered wave calculations on UF6
NASA Technical Reports Server (NTRS)
Case, D. A.; Yang, C. Y.
1980-01-01
Self-consistent Dirac-Slater multiple scattering calculations are presented for UF6. The results are compared critically to other relativistic calculations, showing that the results of all molecular orbital calculations are in qualitative agreement, as measured by energy levels, population analyses, and spin-orbit splittings. A detailed comparison is made to the relativistic X alpha(RX alpha) method of Wood and Boring, which also uses multiple scattering theory, but incorporates relativistic effects in a more approximate fashion. For the most part, the RX alpha results are in agreement with the present results.
USDA-ARS?s Scientific Manuscript database
This study investigated the compositional characteristics and shelf-life of Njangsa seed oil (NSO). Oil from Njangsa had a high polyunsaturated fatty acid (PUFA) content of which alpha eleosteric acid (alpha-ESA), an unusual conjugated linoleic acid was the most prevalent (about 52%). Linoleic acid...
USDA-ARS?s Scientific Manuscript database
Starch, glycogen, maltooligosaccharides, and other alpha-1,4- and alpha-1,6-linked glucose carbohydrates exclusive of resistant starch are collectively termed "dietary starch." This nutritionally important fraction is increasingly measured for use in diet formulation for animals, as it can have posi...
NASA Technical Reports Server (NTRS)
Guiot, R.; Wunnenberg, H.
1980-01-01
The methods by which aerodynamic coefficients are determined and discussed. These include: calculations, wind tunnel experiments and experiments in flight for various prototypes of the Alpha Jet. A comparison of obtained results shows good correlation between expectations and in-flight test results.
Beta-alanine/alpha-ketoglutarate aminotransferase for 3-hydroxypropionic acid production
Jessen, Holly Jean [Chanhassen, MN; Liao, Hans H [Eden Prairie, MN; Gort, Steven John [Apple Valley, MN; Selifonova, Olga V [Plymouth, MN
2011-10-04
The present disclosure provides novel beta-alanine/alpha ketoglutarate aminotransferase nucleic acid and protein sequences having increased biological activity. Also provided are cells containing such enzymes, as well as methods of their use, for example to produce malonyl semialdehyde and downstream products thereof, such as 3-hydroxypropionic acid and derivatives thereof.
EEG Alpha and Beta Activity in Normal and Deaf Subjects.
ERIC Educational Resources Information Center
Waldron, Manjula; And Others
Electroencephalogram and task performance data were collected from three groups of young adult males: profoundly deaf Ss who signed from an early age, profoundly deaf Ss who only used oral (speech and speedreading) methods of communication, and normal hearing Ss. Alpha and Beta brain wave patterns over the Wernicke's area were compared across…
Beta-alanine/alpha-ketoglutarate aminotransferase for 3-hydroxypropionic acid production
Jessen, Holly Jean; Liao, Hans H; Gort, Steven John; Selifonova, Olga V
2014-11-18
The present disclosure provides novel beta-alanine/alpha ketoglutarate aminotransferase nucleic acid and protein sequences having increased biological activity. Also provided are cells containing such enzymes, as well as methods of their use, for example to produce malonyl semialdehyde and downstream products thereof, such as 3-hydroxypropionic acid and derivatives thereof.
Granado-Lorencio, F; Herrero-Barbudo, C; Blanco-Navarro, I; Pérez-Sacristán, B
2010-06-01
Our aim was to assess the suitability of ultra-high performance liquid chromatography (UHPLC) for the simultaneous determination of biomarkers of vitamins A (retinol, retinyl esters), E (alpha- and gamma-tocopherol), D (25-OH-vitamin D), and the major carotenoids in human serum to be used in clinical practice. UHPLC analysis was performed on HSS T3 column (2.1 x 100 mm; 1.8 microm) using gradient elution and UV-VIS detection. The system allows the simultaneous determination of retinol, retinyl palmitate, 25-OH-vitamin D, alpha- and gamma-tocopherol, lutein plus zeaxanthin, alpha-carotene, beta-carotene, alpha- and beta-cryptoxanthin and lycopene. The method showed a good linearity over the physiological range with an adequate accuracy in samples from quality control programs. Suitability of the method in clinical practice was tested by analyzing samples (n = 286) from patients. In conclusion, UHPLC constitutes a reliable approach for nutrient/biomarker profiling allowing the rapid, simultaneous and low-cost determination of vitamins A, E, and D (including vitamers and ester forms) and the major carotenoids in clinical practice.
NASA Astrophysics Data System (ADS)
Schulz, Anke; Trage, Claudia; Schwarz, Helmut; Kroh, Lothar W.
2007-05-01
A new method is presented which allows the simultaneous detection of various [alpha]-dicarbonyl compounds generated in the course of the nonenzymatic browning reaction initiated by thermal treatment of l-ascorbic acid, namely: glyoxal, methylglyoxal, diacetyl, 3-deoxy-l-pentosone, and l-threosoneE 3-Deoxy-l-threosone was successfully identified as a new C4-[alpha]-dicarbonyl structure for the first time in the degradation of Vitamin C by application of this non-chromatographic mass spectrometric approach. Moreover, a more detailed elucidation of the mechanistic scenario with respect to the oxidative and nonoxidative pathways is presented by using dehydro-l-ascorbic acid and 2,3-diketo-l-gulonic acid instead of l-ascorbic acid as a starting material. Furthermore, the postulated pathways are corroborated with the aid of 13C-isotopic labeling studies. The investigations were extended to baby food, and the successful detection of [alpha]-dicarbonyl compounds characteristic for Vitamin C degradation proved the matrix tolerance of the introduced method.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shestermanov, K.E.; Vasiliev, A.N; /Serpukhov, IHEP
2005-12-01
A precise measurement of the angle {alpha} in the CKM triangle is very important for a complete test of Standard Model. A theoretically clean method to extract {alpha} is provided by B{sup 0} {yields} {rho}{pi} decays. Monte Carlo simulations to obtain the BTeV reconstruction efficiency and to estimate the signal to background ratio for these decays were performed. Finally the time-dependent Dalitz plot analysis, using the isospin amplitude formalism for tre and penguin contributions, was carried out. It was shown that in one year of data taking BTeV could achieve an accuracy on {alpha} better than 5{sup o}.
Kurudirek, Murat; Aksakal, Oğuz; Akkuş, Tuba
2015-11-01
A direct method has been used for the first time, to compute effective atomic numbers (Z eff) of water, air, human tissues, and some organic and inorganic compounds, for total electron proton and alpha particle interaction in the energy region 10 keV-1 GeV. The obtained values for Z eff were then compared to those obtained using an interpolation procedure. In general, good agreement has been observed for electrons, and the difference (%) in Z eff between the results of the direct and the interpolation method was found to be <10 % for all materials, in the energy range from 10 keV to 1 MeV. More specifically, results of the two methods were found to agree well (Dif. <10 %) for air, calcium fluoride, kapton polyimide film, paraffin wax and plastic scintillator in the entire energy region with respect to the total electron interaction. On the other hand, values for Z eff calculated using both methods for protons and alpha particles generally agree with each other in the high-energy region above 10 MeV.
Ghaedi, Mehrorang; Asadpour, Enayat; Vafaie, Azam
2006-01-01
A simple and accurate micellanized spectrophotometric method for determination of trace amounts of Cr(III) ion in tab and top water and a synthetic mixture has been described. The micellar method is based on effect of organized molecular assemblies such as micelles in spectrophotometric measurement due to their effect on the systems of interest. The ability of micellar system in solubilizing of sparingly soluble ligand or complexes has been used for increasing figures of merit of an analytical method. Due to solubility increasing in aqueous media requirement for a primary extraction can be eliminated. Using the alpha-benzoin oxime (alpha-BO) spectrophotometric determination of Cr(III) ion has been performed and results are compared. The spectrophotometric determination of Cr(III) ion using alpha-BO in the presence of non-ionic surfactant Triton X-100 has been performed. The influence of type and amount of surfactant, pH, complexation time and amount of ligand were examined. Finally, the repeatability, accuracy and the effect of interfering ions on the determination of Cr(III) ion was evaluated. The proposed methods successfully with recovery yield of almost 100% have been applied to the rapid and simple determination of Cr(III) ion in the real samples. There is a good agreement between methods and atomic absorption spectrometry. The Beers law is obeyed over the concentration range of 0.1-13.7 microg mL(-1) for micellar media. The detection limit is 0.8 ng mL(-1). The molar absorptivity of complex is 5350 L mol(-1) cm(-1).
Ab initio electronic structure of the progestogen norethisterone and its 5 alpha-derivatives.
Kubli-Garfias, Carlos; Vázquez, Ricardo; Cooney, Austin J; Larrea, Fernando
2002-11-01
The steroid 17 alpha-ethynyl-19-nor-4-androsten-17 beta-ol, 3-one (Norethisterone; NET) and its 5 alpha-dihydro (5 alpha-NET), 3 alpha- and 3 beta-tetrahydro derivatives (3 alpha,5 alpha- and 3 beta,5 alpha-NET), were comparatively studied by the ab initio quantum mechanics theory. Additionally, 5 alpha-androstan-3 beta,17 beta-diol (ADIOL) was also studied. The Hartree-Fock method and the 6-31G(*) basis set were used to obtain the lowest energy conformation, geometries, electronic structure and physicochemical properties of the steroids. The results showed bond distances and valence angles similar among all steroids, but some differences in dihedral angles in the A-B-ring system were observed. The electronic structure analysis showed that NET has both frontier orbitals that is, the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) located at the C4-C5 pi-bond. In A-ring reduced derivatives, the HOMO was found at the 17 beta-OH and ethynyl groups. In the case of 5 alpha-NET, the LUMO was confined to the A-ring and its C3 carbonyl group while the two NET tetrahydro-reduced derivatives showed the LUMO at the 17 beta-OH and ethynyl groups. The energy changes of the rotational barrier of the 17 beta-OH group suggest that its movement is somewhat restricted by the 17 alpha-ethynyl group. Interestingly both groups at C17 form a single electrostatic potential with high electronic density. On the other side, the 19-nor condition increases the A-ring mobility. However, the 3 beta-OH group of 3 beta,5 alpha-NET may rotate without significant energy differences as compared to the same group in ADIOL. The electronic structure of NET and its A-ring reduced derivatives explains in some extent their interaction with androgen and progesterone receptors as well as their selectivity for the estrogen alpha-receptor.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yamashita, S.; Masubuchi, Y.; Nakazawa, Y.
2012-10-15
Slight enhancement of saturation magnetization to 219 A m{sup 2} kg{sup -1} was observed from 199 A m{sup 2} kg{sup -1} for the original {alpha}-Fe on the intermediate nitrided mixture of '{alpha} Prime Prime -Fe{sub 16}N{sub 2}' with residual {alpha}-Fe among the low temperature ammonia nitridation products under 5 T magnetic field at room temperature. The value changed not linearly against the yield as had been expected. Crystal structure refinement indicated that the phase similar to {alpha} Prime Prime -Fe{sub 16}N{sub 2} had deviations on its lattice constants and positional parameters, compared to previously reported values for {alpha} Prime Primemore » -Fe{sub 16}N{sub 2}. Spin-polarized total energy calculations were performed using the projector-augmented wave method as implemented in the Vienna ab-initio simulation package (VASP) to calculate magnetic moment on the refined crystal structure of the intermediate '{alpha} Prime Prime -Fe{sub 16}N{sub 2}'. The calculations supported the observed magnetization enhancement in the intermediate nitridation product. - Graphical abstract: Crystal structural parameters slightly change in the intermediate nitrided '{alpha} Prime Prime -Fe{sub 16}N{sub 2}' from those in {alpha} Prime Prime -Fe{sub 16}N{sub 2} to show the magnetization maxima in the mixture of '{alpha} Prime Prime -Fe{sub 16}N{sub 2}' and the residual {alpha}-F. Highlights: Black-Right-Pointing-Pointer Larger magnetization was observed than the value of Fe{sub 16}N{sub 2} on its intermediate nitrided mixture with residual {alpha}-Fe. Black-Right-Pointing-Pointer The enhancement was related to the crystal structural deviation from Fe{sub 16}N{sub 2} on the intermediate nitride. Black-Right-Pointing-Pointer It was supported by spin-polarized total energy calculation using the deviated structure.« less
NASA Technical Reports Server (NTRS)
Srinivasan, R.; Daw, M. S.; Noebe, R. D.; Mills, M. J.
2003-01-01
Ni-44at.% Al and Ni-50at.% single crystals were tested in compression in the hard (001) orientations. The dislocation processes and deformation behavior were studied as a function of temperature, strain and strain rate. A slip transition in NiAl occurs from alpha(111) slip to non-alphaaaaaaaaaaa9111) slip at intermediate temperatures. In Ni-50at.% Al single crystal, only alpha(010) dislocations are observed above the slip transition temperature. In contrast, alpha(101)(101) glide has been observed to control deformation beyond the slip transition temperature in Ni-44at.%Al. alpha(101) dislocations are observed primarily along both (111) directions in the glide plane. High-resolution transmission electron microscopy observations show that the core of the alpha(101) dislocations along these directions is decomposed into two alpha(010) dislocations, separated by a distance of approximately 2nm. The temperature window of stability for these alpha(101) dislocations depends upon the strain rate. At a strain rate of 1.4 x 10(exp -4)/s, lpha(101) dislocations are observed between 800 and 1000K. Complete decomposition of a alpha(101) dislocations into alpha(010) dislocations occurs beyond 1000K, leading to alpha(010) climb as the deformation mode at higher temperature. At lower strain rates, decomposition of a alpha(101) dislocations has been observed to occur along the edge orientation at temperatures below 1000K. Embedded-atom method calculations and experimental results indicate that alpha(101) dislocation have a large Peieris stress at low temperature. Based on the present microstructural observations and a survey of the literature with respect to vacancy content and diffusion in NiAl, a model is proposed for alpha(101)(101) glide in Ni-44at.%Al, and for the observed yield strength versus temperature behavior of Ni-Al alloys at intermediate and high temperatures.
Infection and exposure to vector-borne pathogens in rural dogs and their ticks, Uganda.
Proboste, Tatiana; Kalema-Zikusoka, Gladys; Altet, Laura; Solano-Gallego, Laia; Fernández de Mera, Isabel G; Chirife, Andrea D; Muro, Jesús; Bach, Ester; Piazza, Antonio; Cevidanes, Aitor; Blanda, Valeria; Mugisha, Lawrence; de la Fuente, José; Caracappa, Santo; Millán, Javier
2015-06-05
In rural parts of Africa, dogs live in close association with humans and livestock, roam freely, and usually do not receive prophylactic measures. Thus, they are a source of infectious disease for humans and for wildlife such as protected carnivores. In 2011, an epidemiological study was carried out around three conservation areas in Uganda to detect the presence and determine the prevalence of vector-borne pathogens in rural dogs and associated ticks to evaluate the risk that these pathogens pose to humans and wildlife. Serum samples (n = 105), blood smears (n = 43) and blood preserved on FTA cards (n = 38) and ticks (58 monospecific pools of Haemaphysalis leachi and Rhipicephalus praetextatus including 312 ticks from 52 dogs) were collected from dogs. Dog sera were tested by indirect immunofluorescence to detect the presence of antibodies against Rickettsia conorii and Ehrlichia canis. Antibodies against R. conorii were also examined by indirect enzyme immunoassay. Real time PCR for the detection of Rickettsia spp., Anaplasmataceae, Bartonella spp. and Babesia spp. was performed in DNA extracted from FTA cards and ticks. 99% of the dogs were seropositive to Rickettsia spp. and 29.5% to Ehrlichia spp. Molecular analyses revealed that 7.8% of the blood samples were infected with Babesia rossi, and all were negative for Rickettsia spp. and Ehrlichia spp. Ticks were infected with Rickettsia sp. (18.9%), including R. conorii and R. massiliae; Ehrlichia sp. (18.9%), including E. chaffeensis and Anaplasma platys; and B. rossi (1.7%). Bartonella spp. was not detected in any of the blood or tick samples. This study confirms the presence of previously undetected vector-borne pathogens of humans and animals in East Africa. We recommend that dog owners in rural Uganda be advised to protect their animals against ectoparasites to prevent the transmission of pathogens to humans and wildlife.
Batiz, M. F. Rossi; Marino de Remes Lenicov, A. M.; Hagedorn, Henry
2014-01-01
Abstract The five immature stages of the planthopper Lacertinella australis (Remes Lenicov and Rossi Batiz) (Hemiptera: Delphacidae: Saccharosydnini) are described and illustrated. The main characters that allowed us to distinguish the various stages were body size, number of tarsomeres and metatibial spines, and number of teeth on the spur. New biological data based on laboratory rearing and field observations showed that L. australis can carry out its biological cycle successfully on the graminaceous pampas grass ( Cortaderia spp. Stapf (Poales: Poaceae)). In addition, the efficient rearing in captivity, the high survivorship registered, and overwintering only on this host plant suggests that L. australis is a potential biocontrol agent of this invasive graminaceous weed. This study provides information about the immature stages , including a key for their identification, based on laboratory reared specimens and field observations. Resumen Se describen e ilustran las cinco etapas inmaduras de la especie de Saccharisydnini Lacertinella australis (Remes Lenicov and Rossi Batiz) (Hemiptera: Delphacidae). Los principales caracteres que permitieron distinguir las diferentes etapas fueron: tamaño corporal, número de espinas en los tarsómeros y metatibia y número de dientes en el espolón tibial. Nuevos datos biológicos, basados en la cría de laboratorio y observaciones de campo, mostraron que L. australis puede realizar su ciclo biológico exitosamente en la graminácea cortadera ( Cortaderia spp. Stapf (Poales: Poaceae)). Además, la eficiente crianza en cautive-rio y la alta supervivencia registrada en esta planta hospedera, sugieren que L. australis podría ser usada como un potencial agente de control biológico de esta maleza invasora. Este estudio proporciona informa-ción sobre las etapas inmaduras, incluyendo una clave para su identificación, basada en individuos provenientes de la cría de laboratorio y de campo. PMID:25199992
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dasgupta-Schubert, N.; Reyes, M.A.
2007-11-15
The predictive accuracy of the generalized liquid drop model (GLDM) formula for alpha-decay half-lives has been investigated in a detailed manner and a variant of the formula with improved coefficients is proposed. The method employs the experimental alpha half-lives of the well-known alpha standards to obtain the coefficients of the analytical formula using the experimental Q{sub {alpha}} values (the DSR-E formula), as well as the finite range droplet model (FRDM) derived Q{sub {alpha}} values (the FRDM-FRDM formula). The predictive accuracy of these formulae was checked against the experimental alpha half-lives of an independent set of nuclei (TEST) that span approximatelymore » the same Z, A region as the standards and possess reliable alpha spectroscopic data, and were found to yield good results for the DSR-E formula but not for the FRDM-FRDM formula. The two formulae were used to obtain the alpha half-lives of superheavy elements (SHE) and heavy nuclides where the relative accuracy was found to be markedly improved for the FRDM-FRDM formula, which corroborates the appropriateness of the FRDM masses and the GLDM prescription for high Z, A nuclides. Further improvement resulted, especially for the FRDM-FRDM formula, after a simple linear optimization over the calculated and experimental half-lives of TEST was used to re-calculate the half-lives of the SHE and heavy nuclides. The advantage of this optimization was that it required no re-calculation of the coefficients of the basic DSR-E or FRDM-FRDM formulae. The half-lives for 324 medium-mass to superheavy alpha decaying nuclides, calculated using these formulae and the comparison with experimental half-lives, are presented.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Silvaggi,N.; Zhang, C.; Lu, Z.
2006-01-01
Carbohydrate-deficient glycoprotein syndrome type 1a (CDG-1a) is a congenital disease characterized by severe defects in nervous system development. It is caused by mutations in alpha -phosphomannomutase (of which there are two isozymes, {alpha}-PMM1 and {alpha}-PPM2). Here we report the X-ray crystal structures of human {alpha}-PMM1 in the open conformation, with and without the bound substrate, {alpha}-D-mannose 1-phosphate. {alpha}-PMM1, like most Haloalkanoic Acid Dehalogenase Superfamily (HADSF) members, consists of two domains, the cap and core, which open to bind substrate and then close to provide a solvent exclusive environment for catalysis. The substrate phosphate group is observed at a positively chargedmore » site of the cap domain, rather than at the core domain phosphoryl-transfer site defined by the D19 nucleophile and Mg{sup 2+} cofactor. This suggests that substrate binds first to the cap and then is swept into the active site upon cap closure. The orientation of the acid/base residue D21 suggests that {alpha}-PMM uses a different method of protecting the aspartylphosphate from hydrolysis than the HADSF member {beta}-phosphoglucomutase. It is hypothesized that the electrostatic repulsion of positive charges at the interface of the cap and core domains stabilizes {alpha}-PMM1 in the open conformation, and that the negatively charged substrate binds to the cap, thereby facilitating its closure over the core domain. The two isozymes {alpha}-PMM1 and {alpha}-PMM2 are shown to have a conserved active-site structure and to display similar kinetic properties. Analysis of the known mutation sites in the context of the structures reveals the genotype-phenotype relationship underlying CDG-1a.« less
Legraverend, C; Antonson, P; Flodby, P; Xanthopoulos, K G
1993-01-01
The promoter region of the mouse CCAAT-Enhancer Binding Protein (C/EBP alpha) gene is capable of directing high levels of expression of reporter constructs in various cell lines, albeit even in cells that do not express their endogenous C/EBP alpha gene. To understand the molecular mechanisms underlying this ubiquitous expression, we have characterized the promoter region of the mouse C/EBP alpha gene by a variety of in vitro and in vivo methods. We show that three sites related in sequence to USF, BTE and C/EBP binding sites and present in promoter region -350/+3, are recognized by proteins from rat liver nuclear extracts. The sequence of the C/EBP alpha promoter that includes the USF binding site is also capable of forming stable complexes with purified Myc+Max heterodimers and mutation of this site drastically reduces transcription of C/EBP alpha promoter luciferase constructs both in liver and non liver cell lines. In addition, we identify three novel protein-binding sites two of which display similarity to NF-1 and a NF kappa B binding sites. The region located between nucleotides -197 and -178 forms several heat-stable complexes with liver nuclear proteins in vitro which are recognized mainly by antibodies specific for C/EBP alpha. Furthermore, transient expression of C/EBP alpha and to a lesser extent C/EBP beta expression vectors, results in transactivation of a cotransfected C/EBP alpha promoter-luciferase reporter construct. These experiments support the notion that the C/EBP alpha gene is regulated by C/EBP alpha but other C/EBP-related proteins may also be involved. Images PMID:8493090
TNF-alpha-308G>A polymorphism and the risk of familial CAD in a Pakistani population.
Hussain, Sabir; Iqbal, Tahir; Javed, Qamar
2015-01-01
A case-control and trio-families study was performed to establish a potential association between TNF-alpha gene promoter SNPs at -308 and -238, and occurrence of CAD in a Pakistani population. In the first phase, 150 patients and 150 controls were enrolled in the case-control association study. In the second phase, heritability of susceptible alleles was investigated from 88 trio-families with CAD affected offspring. Biochemical analysis of lipids and hs-CRP was carried out spectrophotometrically, while serum TNF-alpha concentrations were determined by enzyme-linked immunosorbent assay. Genotyping of the TNF-alpha SNPs were determined by PCR-RFLP method. Elevated serum TNF-alpha and hs-CRP were observed from CAD vs. controls (P<0.0001; for both). The evaluation of TNF-alpha-308G>A polymorphism in case-control study revealed that the said SNP was significantly associated with the increased risk of CAD. The findings demonstrated a significant link between the TNF-alpha variant allele A at -308 and CAD (P=0.0035), whereas the -238 SNP was not associated with the disease. Haplotype A-G of the TNF-alpha gene at -308G>A and -238G>A showed higher frequency in the patient group compared with controls (P<0.05). Moreover, data showed preferential transmission of the disease susceptible allele A at TNF-alpha-308 from parent to affected offspring in a trio-family study (P<0.0001). The current research leads to conclusion that the TNF-alpha-308G>A polymorphism is associated with CAD in the study population. Furthermore, for the first time, we showed that the TNF-alpha-308A allele was significantly associated with the familial CAD in our high risk population. Copyright © 2014. Published by Elsevier Inc.
NASA Technical Reports Server (NTRS)
Tamma, Kumar K.; D'Costa, Joseph F.
1991-01-01
This paper describes the evaluation of mixed implicit-explicit finite element formulations for hyperbolic heat conduction problems involving non-Fourier effects. In particular, mixed implicit-explicit formulations employing the alpha method proposed by Hughes et al. (1987, 1990) are described for the numerical simulation of hyperbolic heat conduction models, which involves time-dependent relaxation effects. Existing analytical approaches for modeling/analysis of such models involve complex mathematical formulations for obtaining closed-form solutions, while in certain numerical formulations the difficulties include severe oscillatory solution behavior (which often disguises the true response) in the vicinity of the thermal disturbances, which propagate with finite velocities. In view of these factors, the alpha method is evaluated to assess the control of the amount of numerical dissipation for predicting the transient propagating thermal disturbances. Numerical test models are presented, and pertinent conclusions are drawn for the mixed-time integration simulation of hyperbolic heat conduction models involving non-Fourier effects.
Joseph, T K; Kartha, C P
1982-01-01
Centring of spectacle lenses is much neglected field of ophthalmology. The prismatic effect caused by wrong centring results in a phoria on the eye muscles which in turn causes persistent eyestrain. The theory of visual axis, optical axis and angle alpha is discussed. Using new methods the visual axis and optical axis of 35 subjects were measured. The results were computed for facial asymmetry, parallax error, angle alpha and also decentration for near vision. The results show that decentration is required on account of each of these factors. Considerable correction is needed in the vertical direction, a fact much neglected nowadays; and vertical decentration results in vertical phoria which is more symptomatic than horizontal phorias. Angle Alpha was computed for each of these patients. A new devise called 'The Kerala Decentration Meter' using the pinhole method for measuring the degree of decentration from the datum centre of the frame, and capable of correcting all the factors described above, is shown with diagrams.
Karsonova, A V; Shulzhenko, A E; Karaulov, A V
2014-01-01
Study of features of NK-cell response to the effect of recombinant IFN-alpha in complex with evaluation of the ability to synthesize inherent IFN-alpha in patients with frequently recurrent herpes simplex (FRHS). 48 patients with genital (n = 31), labial (n = 10) and mixed localization (n = 7) FRHS diagnosis were observed. 31 healthy donors composed the control group. MC were cultivated in the presence of a recombinant human IFN-alpha2b at the concentration of 10, 100 and 1000 U/ml for 24 hours. NK-cell response to the effect of IFN-alpha was evaluated after 24 hours using flow cytometry by degranulation reaction and in the NK-activity test. IFN-alpha synthesis was evaluated in HSV-1, HSV-2 and Newcastle disease virus stimulated cell supernatants by EIA method. Patients with FRHS were established to be a heterogeneous group by parameters in the IFN-alpha/NK-cell cytotoxicity system. 2 types of NK-cell response to the stimulation by recombinant IFN-alpha were identified. Type A is characterized by a decrease of NK-cell response to IFN-alpha in the remission phase and does not have this defect in the exacerbation phase. Synthesis of inherent IFN-alpha in response to viral inductors for type A was comparable with the response in healthy donors in both phases. On the contrary type B having normal sensitivity of NK-cells to IFN-alpha in the remission phase is characterized by a decrease of this parameter in the exacerbation phase for more than 3 times. Synthesis of inherent IFN-alpha in response to viral inductors during type B is increased in the remission phase and decreased in the exacerbation phase. During immune-correcting therapy of FRHS a personalized approach taking into account features of NK-cell response to IFN-alpha is necessary, because types A and B have principal differences by cytotoxicity parameters of NK-cells and their change under the effect of IFN-alpha, as well as by parameters of IFN-alpha synthesis in response to viral inductors at various phases of the clinical process.
Wyatt, Amy R.; Kumita, Janet R.; Farrawell, Natalie E.; Dobson, Christopher M.; Wilson, Mark R.
2015-01-01
Alpha-2-macroglobulin is an abundant secreted protein that is of particular interest because of its diverse ligand binding profile and multifunctional nature, which includes roles as a protease inhibitor and as a molecular chaperone. The activities of alpha-2-macroglobulin are typically dependent on whether its conformation is native or transformed (i.e. adopts a more compact conformation after interactions with proteases or small nucleophiles), and are also influenced by dissociation of the native alpha-2-macroglobulin tetramer into stable dimers. Alpha-2-macroglobulin is predominately present as the native tetramer in vivo; once purified from human blood plasma, however, alpha-2-macroglobulin can undergo a number of conformational changes during storage, including transformation, aggregation or dissociation. We demonstrate that, particularly in the presence of sodium chloride or amine containing compounds, freezing and/or lyophilization of alpha-2-macroglobulin induces conformational changes with functional consequences. These conformational changes in alpha-2-macroglobulin are not always detected by standard native polyacrylamide gel electrophoresis, but can be measured using bisANS fluorescence assays. Increased surface hydrophobicity of alpha-2-macroglobulin, as assessed by bisANS fluorescence measurements, is accompanied by (i) reduced trypsin binding activity, (ii) increased chaperone activity, and (iii) increased binding to the surfaces of SH-SY5Y neurons, in part, via lipoprotein receptors. We show that sucrose (but not glycine) effectively protects native alpha-2-macroglobulin from denaturation during freezing and/or lyophilization, thereby providing a reproducible method for the handling and long-term storage of this protein. PMID:26103636
García-Sesnich, Jocelyn N; Flores, Mauricio Garrido; Ríos, Marcela Hernández; Aravena, Jorge Gamonal
2017-01-01
Context: Stress is defined as an alteration of an organism's balance in response to a demand perceived from the environment. Diverse methods exist to evaluate physiological response. A noninvasive method is salivary measurement of cortisol and alpha-amylase. A growing body of evidence suggests that the regular practice of Yoga would be an effective treatment for stress. Aims: To determine the Kundalini Yoga (KY) effect, immediate and after 3 months of regular practice, on the perception of psychological stress and the salivary levels of cortisol and alpha-amylase activity. Settings and Design: To determine the psychological perceived stress, levels of cortisol and alpha-amylase activity in saliva, and compare between the participants to KY classes performed for 3 months and a group that does not practice any type of yoga. Subjects and Methods: The total sample consisted of 26 people between 18 and 45-year-old; 13 taking part in KY classes given at the Faculty of Dentistry, University of Chile and 13 controls. Salivary samples were collected, enzyme-linked immunosorbent assay was performed to quantify cortisol and kinetic reaction test was made to determine alpha-amylase activity. Perceived Stress Scale was applied at the beginning and at the end of the intervention. Statistical Analysis Used: Statistical analysis was applied using Stata v11.1 software. Shapiro–Wilk test was used to determine data distribution. The paired analysis was fulfilled by t-test or Wilcoxon signed-rank test. T-test or Mann–Whitney's test was applied to compare longitudinal data. A statistical significance was considered when P < 0.05. Results: KY practice had an immediate effect on salivary cortisol. The activity of alpha-amylase did not show significant changes. A significant decrease of perceived stress in the study group was found. Conclusions: KY practice shows an immediate effect on salivary cortisol levels and on perceived stress after 3 months of practice. PMID:28546677
DOE Office of Scientific and Technical Information (OSTI.GOV)
O'Hara, Matthew J.; Addleman, R. Shane
Radioactive contamination in the environment, be it from accidental or intentional release, can create an urgent need to assess water and food supplies, the environment, and monitor human health. Alpha-emitting radionuclides represent the most ionizing, and therefore the most damaging, form of radiation when internalized. Additionally, because of its ease of energy attenuation in solids or liquids, alpha emissions cannot be reliably monitored using non-destructive means. In the event of such an emergency, rapid and efficient methods will be needed to screen scores of samples (food, water, and human excreta) within a short time window. Unfortunately, the assay of alpha-emittingmore » radionuclides using traditional radioanalytical methods is typically labor intensive and time consuming. The creation of analytical counting sources typically requires a series of chemical treatment steps to achieve well performing counting sources. In an effort to devise radioanalytical methods that are fast, require little labor, and minimize the use of toxic or corrosive agents, researchers at PNNL have evaluated magnetite (Fe3O4) nanoparticles as extracting agents for alpha-emitting radionuclides from chemically unmodified aqueous systems. It is demonstrated that bare magnetic nanoparticles exhibit high affinity for representative α-emitting radionuclides (241Am and 210Po) from representative aqueous matrices: river and ground water. Furthermore, use of the magnetic properties of these materials to concentrate the sorbed analyte from the bulk aqueous solution has been demonstrated. The nanoparticle concentrate can be either directly dispensed into scintillation cocktail, or first dissolved and then added to scintillation cocktail as a solution for alpha emission assay by liquid scintillation analysis. Despite the extreme quench caused by the metal oxide suspensions, the authors have demonstrated that quench correction features available on modern liquid scintillation analyzers can be employed to assure that quench-induced analytical biases can be avoided.« less
2013-01-01
Background Intraoperative detection of 18F-FDG-avid tissue sites during 18F-FDG-directed surgery can be very challenging when utilizing gamma detection probes that rely on a fixed target-to-background (T/B) ratio (ratiometric threshold) for determination of probe positivity. The purpose of our study was to evaluate the counting efficiency and the success rate of in situ intraoperative detection of 18F-FDG-avid tissue sites (using the three-sigma statistical threshold criteria method and the ratiometric threshold criteria method) for three different gamma detection probe systems. Methods Of 58 patients undergoing 18F-FDG-directed surgery for known or suspected malignancy using gamma detection probes, we identified nine 18F-FDG-avid tissue sites (from amongst seven patients) that were seen on same-day preoperative diagnostic PET/CT imaging, and for which each 18F-FDG-avid tissue site underwent attempted in situ intraoperative detection concurrently using three gamma detection probe systems (K-alpha probe, and two commercially-available PET-probe systems), and then were subsequently surgical excised. Results The mean relative probe counting efficiency ratio was 6.9 (± 4.4, range 2.2–15.4) for the K-alpha probe, as compared to 1.5 (± 0.3, range 1.0–2.1) and 1.0 (± 0, range 1.0–1.0), respectively, for two commercially-available PET-probe systems (P < 0.001). Successful in situ intraoperative detection of 18F-FDG-avid tissue sites was more frequently accomplished with each of the three gamma detection probes tested by using the three-sigma statistical threshold criteria method than by using the ratiometric threshold criteria method, specifically with the three-sigma statistical threshold criteria method being significantly better than the ratiometric threshold criteria method for determining probe positivity for the K-alpha probe (P = 0.05). Conclusions Our results suggest that the improved probe counting efficiency of the K-alpha probe design used in conjunction with the three-sigma statistical threshold criteria method can allow for improved detection of 18F-FDG-avid tissue sites when a low in situ T/B ratio is encountered. PMID:23496877
Nielen, Michel W F; Rutgers, Paula; van Bennekom, Eric O; Lasaroms, Johan J P; van Rhijn, J A Hans
2004-03-05
The origin, i.e. natural occurrence or illegal treatment, of findings of 17alpha-boldenone (alpha-Bol) and 17beta-boldenone (beta-Bol) in urine and faeces of cattle is under debate within the European Union. A liquid chromatographic positive ion electrospray tandem mass spectrometric method is presented for the confirmatory analysis of 17beta-boldenone, 17alpha-boldenone and an important metabolite/precursor androsta-1,4-diene-3,17-dione (ADD), using deuterium-labelled 17beta-boldenone (beta-Bol-d3) as internal standard. Detailed sample preparation procedures were developed for a variety of sample matrices such as bovine urine, faeces, feed and skin swab samples. The method was validated as a quantitative confirmatory method according to the latest EU guidelines and shows good precision, linearity and accuracy data, and CCalpha and CCbeta values of 0.1-0.3 and 0.4-1.0 ng/ml, respectively. Currently, the method has been successfully applied to suspect urine samples for more than a year, and occasionally to faeces, feed and swab samples as well. Results obtained from untreated and treated animals are given and their impact on the debate about the origin of residues of 17beta-boldenone is critically discussed. Finally, preliminary data about the degree of conjugation of boldenone residues are presented and a simple procedure for discrimination between residues from abuse versus natural origin is proposed.
Cope, S. Joseph; Hayes, Robert B.
2018-03-01
Radon ( 222Rn) and thoron ( 220Rn) progeny (primarily bismuth and polonium) are known interferents when rapid evaluation of transuranic content on air filters is of interest. These complexities stem from the overlapping energies of the progeny alpha particles onto the transuranic region of interest (3–5.5 MeV) where naturally-occurring alpha emitters can overwhelm the spectra. Due to the immediacy of the alpha counting methods employed, coupled with the half-life of thoron progeny dominated by 212Pb (t 1/2=10.6 h), a conservative transuranic activity estimate with rigorous uncertainty is being sought. A successful transuranic activity estimation method will incorporate any thoron progenymore » present on the filter providing 95% confidence decision levels in which a filter may be evaluated for emergency response applications. Twenty-three pairs of samples of various duration having no transuranic content were taken over a 2-mo period. The resulting filters were counted in a time series before non-linear least squares decay curve fitting was applied to the decay profile. For the samples considered, a transuranic activity estima-tor decision level was determined at 0.2 Bq for the given geographic location and months analyzed. In conclusion, validation of this method for other seasonal and geographic regions could provide enhanced emergency response capability when the presence of transuranic activity is suspected.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cope, S. Joseph; Hayes, Robert B.
Radon ( 222Rn) and thoron ( 220Rn) progeny (primarily bismuth and polonium) are known interferents when rapid evaluation of transuranic content on air filters is of interest. These complexities stem from the overlapping energies of the progeny alpha particles onto the transuranic region of interest (3–5.5 MeV) where naturally-occurring alpha emitters can overwhelm the spectra. Due to the immediacy of the alpha counting methods employed, coupled with the half-life of thoron progeny dominated by 212Pb (t 1/2=10.6 h), a conservative transuranic activity estimate with rigorous uncertainty is being sought. A successful transuranic activity estimation method will incorporate any thoron progenymore » present on the filter providing 95% confidence decision levels in which a filter may be evaluated for emergency response applications. Twenty-three pairs of samples of various duration having no transuranic content were taken over a 2-mo period. The resulting filters were counted in a time series before non-linear least squares decay curve fitting was applied to the decay profile. For the samples considered, a transuranic activity estima-tor decision level was determined at 0.2 Bq for the given geographic location and months analyzed. In conclusion, validation of this method for other seasonal and geographic regions could provide enhanced emergency response capability when the presence of transuranic activity is suspected.« less
MOLECULAR SIEVES ADSORB IODINE-131 FROM AIR
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wahlgren, M.A.; Meinke, W.W.
1957-09-01
Consideration has been given to the problem of separating and estimating U, Po, nnd other alpha emitters (in order to provide analytical methods for their routine determination in conformity with the draft agreement on the Harwell effluent). Uranium may be ether extracted from solutions of NH/sub 4/NO/sub 3/ as salting out agent at pH1 with an efficiency of 98 to 99%. The deposition of Po on Ag foil is a specific method for this element and under prescribed conditions similar extraction efficiencies may be obtained. An adequate separation from all "other alpha emitters" is obtained and methods for the estimationmore » of these are discussed. A comprehensive scheme involving a preliminary activity concentration step has been elaborated. U, Po, and the majority of the "other alpha emitters" are precipitated as their tannin complexes at pH8 using Ca(OH)/sub 2/, the calcium-tannin complex acting as a carrier. That part of the activity remaining in solution is determined as in the total activity method, previously described. From the solution of the precipitate, Po is first separated by electrodeposition, and then U by ether extraction in the presence of NH/sub 4/NO/sub 3/. The majority of the "other alpha emitters" still in the aqueous NH/sub 4/NO/sub 3/ solution are collected on a second calcium-tannin precipitate, while the small part remaining in solution after this operation is obtained by direct evaporation. (auth)« less
NASA Astrophysics Data System (ADS)
Neish, Calum S.; Martin, Ian L.; Davies, Martin; Henderson, Robert M.; Edwardson, J. Michael
2003-08-01
We have developed an atomic force microscopy (AFM)-based method for the determination of the subunit architecture of ionotropic receptors, and tested the method using the GABAA receptor as a model system. The most common form of the GABAA receptor probably consists of 2alpha1-, 2beta2- and 1gamma2-subunits. We show here that the arrangement of subunits around the central Cl- ion channel can be deduced by AFM of receptors tagged with subunit-specific antibodies. Transfection of cells with DNA encoding alpha1-, beta2- and gamma2-subunits resulted in the production of receptors containing all three subunits, as judged by both immunoblot analysis and the binding of [3H]-Ro15-1788, a specific radioligand for the GABAA receptor. A His6-tag on the alpha1-subunit was used to purify the receptor from membrane fractions of transfected cells. After incubation with anti-His6 immunoglobulin G, some receptors became tagged with either one or two antibody molecules. AFM analysis of complexes containing two bound antibodies showed that the most common angle between the two tags was 135°, close to the value of 144° expected if the two alpha-subunits are separated by a third subunit. This method is applicable to the complete elucidation of the subunit arrangement around the GABAA receptor rosette, and can also be applied to other ionotropic receptors.
Canella, Richard Prazeres; Adam, Guilherme Pradi; de Castillo, Roberto André Ulhôa; Codonho, Daniel; Ganev, Gerson Gandhi; de Vicenzi, Luiz Fernando
2016-01-01
Objective To correlate the angles between the acetabulum and the proximal femur in symptomatic patients with femoroacetabular impingement (FAI), using computed tomography (CT). Methods We retrospectively evaluated 103 hips from 103 patients, using multislice CT to measure the acetabular age, acetabular version (in its supraequatorial portion and in its middle third), femoral neck version, cervical-diaphyseal and alpha angles and the acetabular depth. For the statistical analysis, we used the Pearson correlation coefficient. Results There were inverse correlations between the following angles: (1) acetabular coverage versus alpha angle (p = 0.019); (2) acetabular version (supraequatorial) versus alpha angle (p = 0.049). For patients with femoral anteversion lower than 15 degrees: (1) acetabular version (supraequatorial) versus alpha angle (p = 0.026); (2) acetabular version (middle third) versus alpha angle (p = 0.02). For patients with acetabular version (supraequatorial) lower than 10 degrees: (1) acetabular version (supraequatorial) versus alpha angle (p = 0.004); (2) acetabular version (middle third) versus alpha angle (p = 0.009). Conclusion There was a statistically significant inverse correlation between the acetabular version and alpha angles (the smaller the acetabular anteversion angle was, the larger the alpha angle was) in symptomatic patients, thus supporting the hypothesis that FAI occurs when cam and pincer findings due to acetabular retroversion are seen simultaneously, and that the latter alone does not cause FAI, which leads to overdiagnosis in these cases. PMID:27069890
Structural Studies of Human Pyruvate Dehydrogenase
NASA Technical Reports Server (NTRS)
Ciszak, Ewa; Korotchkina, Lioubov G.; Dominiak, Paulina; Sidhu, Sukhdeep; Patel, Mulchand S.; Curreri, Peter A. (Technical Monitor)
2002-01-01
Human pyruvate dehydrogenase (E1) catalyzes the irreversible decarboxylation of pyruvate in the presence of Mg(2+) and thiamin pyrophosphate (TPP) followed by the rate-limiting reductive acetylation of the lipoyl moiety linked to dihydrolipoamide acetyltransferase. The three-dimensional structure of human E1 is elucidated using the methods of macromolecular X-ray crystallography. The structure is an alpha, alpha', beta and beta' tetramer with the protein units being in the tetrahedral arrangement. Each 361-residue alpha-subunit and 329-residue beta-subunit is composed of a beta-sheet core surrounded by alpha-helical domains. Each subunit is in extensive contact with all the three subunits involving TPP and magnesium cofactors, and potassium ions. The two binding sites for TPP are at the alpha-beta' and alpha'-beta interfaces, each involving a magnesium ion and Phe6l, His63, Tyr89, and Met200 from the alpha-subunit (or alpha'-subunit), and Met81 Phe85, His128 from the beta-subunit (or beta'-subunit). K+ ions are nestled between two beta-sheets and the end of an alpha-helix in each beta-subunit, where they are coordinated by four carbonyl oxygen groups from Ile12, Ala160, Asp163, and Asnl65, and a water molecule. The catalytic C2 carbon of thiazolium ring in this structure forms a 3.2 A contact with a water molecule involved in a series of H-bonds with other water molecules, and indirectly with amino acids including those involved in the catalysis and regulation of the enzyme.
A New Approach for Alpha Radiography by Triple THGEM using Monte Carlo Simulation and Measurement
NASA Astrophysics Data System (ADS)
Khezripour, S.; Negarestani, A.; Rezaie, M. R.
2018-05-01
In this research, alpha imaging in Self Quenching Streamer (SQS) mode is investigated using a triple Thick Gas Electron Multiplier (THGEM) detector by Monte Carlo method and experimental data. First, a semi-empirical equation is derived to represent the relation between the SQS voltage and the alpha energy in every hole of the triple THGEM. The accuracy of this equation is tested and confirmed by a high degree of consistency. Secondly, the images of objects that are irradiated by Am-241 alpha source (5.49 MeV) are recorded by a CMOS camera using triple THGEM detector in the SQS mode. The resolution of images in this paper is a function of the exposure time. For an alpha source with 150 kBq activity, an optimal time interval for exposure is about 30 sec. For exposure time less or more than 30 sec, the images are incomplete and ambiguous, respectively. The overall objective of this work is to facilitate the alpha radiography in nuclear imaging through a triple THGEM without any amplifier or complicated electrical equipment.
Singh, G; Kapoor, I P S; Singh, Pratibha; de Heluani, Carola S; de Lampasona, Marina P; Catalan, Cesar A N
2010-04-01
The phytoconstituents of essential oil and ethanol oleoresin of fresh and dry rhizomes of turmeric (Curcuma longa Linn.) were analyzed by GC-MS. The major constituents were aromatic-turmerone (24.4%), alpha-turmerone (20.5%) and beta-turmerone (11.1%) in fresh rhizome and aromatic-turmerone (21.4%), alpha-santalene (7.2%) and aromatic-curcumene (6.6%) in dry rhizome oil. Whereas, in oleoresins, the major components were alpha-turmerone (53.4%), beta-turmerone (18.1%) and aromatic-turmerone (6.2%) in fresh and aromatic-turmerone (9.6%), alpha-santalene (7.8%) and alpha-turmerone (6.5%) in dry rhizome. Results showed that alpha-turmerone, a major component in fresh rhizomes is only minor one in dry rhizomes. Also, the content of beta-turmerone in dry rhizomes is less than a half amount found in fresh rhizomes. The antioxidant properties have been assessed by various lipid peroxidation assays as well as DPPH radical scavenging and metal chelating methods. The essential oil and ethanol oleoresin of fresh rhizomes have higher antioxidant properties as compared dry ones. 2010 Elsevier Ltd. All rights reserved.
O'Donnell, R G; Mitchell, P I; Priest, N D; Strange, L; Fox, A; Henshaw, D L; Long, S C
1997-08-18
Concentrations of plutonium-239, plutonium-240, strontium-90 and total alpha-emitters have been measured in children's teeth collected throughout Great Britain and Ireland. The concentrations of plutonium and strontium-90 were measured in batched samples, each containing approximately 50 teeth, using low-background radiochemical methods. The concentrations of total alpha-emitters were determined in single teeth using alpha-sensitive plastic track detectors. The results showed that the average concentrations of total alpha-emitters and strontium-90 were approximately one to three orders of magnitude greater than the equivalent concentrations of plutonium-239,240. Regression analyses indicated that the concentrations of plutonium, but not strontium-90 or total alpha-emitters, decreased with increasing distance from the Sellafield nuclear fuel reprocessing plant-suggesting that this plant is a source of plutonium contamination in the wider population of the British Isles. Nevertheless, the measured absolute concentrations of plutonium (mean = 5 +/- 4 mBq kg-1 ash wt.) were so low that they are considered to present an insignificant radiological hazard.
Hunt, J G; Watchman, C J; Bolch, W E
2007-01-01
Absorbed fraction (AF) calculations to the human skeletal tissues due to alpha particles are of interest to the internal dosimetry of occupationally exposed workers and members of the public. The transport of alpha particles through the skeletal tissue is complicated by the detailed and complex microscopic histology of the skeleton. In this study, both Monte Carlo and chord-based techniques were applied to the transport of alpha particles through 3-D microCT images of the skeletal microstructure of trabecular spongiosa. The Monte Carlo program used was 'Visual Monte Carlo--VMC'. VMC simulates the emission of the alpha particles and their subsequent energy deposition track. The second method applied to alpha transport is the chord-based technique, which randomly generates chord lengths across bone trabeculae and the marrow cavities via alternate and uniform sampling of their cumulative density functions. This paper compares the AF of energy to two radiosensitive skeletal tissues, active marrow and shallow active marrow, obtained with these two techniques.
Equatorial Layered Deposits in Arabia Terra, Mars: Facies and Process Variability
NASA Astrophysics Data System (ADS)
Pondrelli, M.; Rossi, A.; van Gasselt, S.; Le Deit, L.; Glamoclija, M.; Cavalazzi, B.; Franchi, F.; Fueten, F.; Hauber, E.; Zegers, T.
2012-12-01
Genetic mechanisms proposed to explain Equatorial Layered Deposits (ELDs) formation include subglacial volcanism, aeolian/airfall, lacustrine, lacustrine/volcanic and spring-fed deposition. ELDs have been frequently shown to consist of sulfates (e.g. Gendrin et al., 2005) that might form as a response to evaporation in a playa environment (Hoefen et al., 2003) or during spring precipitation (e.g. Allen and Oehler, 2008; Rossi et al., 2008). The importance of groundwater-dominated hydrological systems was proposed to explain the formation of light-toned deposits in Meridiani Planum and Arabia Terra (e.g. Andrews-Hanna et al. 2007). Additionally, fluid expulsion processes have been invoked to explain the formation of mounds within the light-toned deposits in Arabia Terra (Allen and Oehler, 2008; Rossi et al., 2008; Pondrelli et al., 2011). Potential for habitable conditions of both playa and spring-related settings (Cavalazzi et al., 2007; Glamoclija et al., 2011) coupled with the high preservation potential within sulfates (Panieri et al., 2010), make these deposits a good candidate to understand the potential past habitability of the planet. In order to investigate ELDs genesis, an area in the vicinity of Firsoff crater, where ELDs are present within and outside the craters, was selected for geological mapping and analysis of the landforms and their association using the available dataset, including CRISM in order to infer ELDs composition. Within Firsoff crater, ELDs form a bulge that can be estimated to be at least a few hundred meters thick, while, outside the craters, ELDs form flat-lying deposits. Although heavily eroded by wind and carved by yardangs, several morphologies within the ELDs in the craters seem to be depositional, which would exclude that the entire Firsoff basin had been originally filled by ELDs. Within craters, ELDs consist of roughly meter thick layers draping and onlapping the substratum. They appear affected by polygonal patterns with no evidence of sedimentary structures. Polyhydrated sulfates have been detected. At places, ELDs appear to be linked to and possibly sourced from tectonically controlled lineaments. Large cone-shaped mounds (100 to 500 m) are situated locally on top of ELDs. They consist of boulders embedded in a matrix, and about one-third of them display an orifice at their top. Outside of the craters, ELDs show large-scale cross stratification associated to duneforms, which suggests an aeolian origin possibly associated to playa deposits. We distinguish between fluid expulsion ELDs forming within the crater and aeolian ELDs outside and possibly inside the craters. Fluid expulsion ELDs would result from groundwater upwelling and following evaporitic precipitation, whereas aeolian ELDs would result from reworking and redeposition of the spring ELDs. References Allen and Oehler (2008), Astrobiology, 8, 1093-1112. Andrews-Hanna et al. (2007), Nature, 446, 163-166. Cavalazzi et al. (2007), Sed. Geol., 200, 73-88. Gendrin et al. (2005), Science, 307, 1587. Glamoclija et al. (2011), Geomicrob. J., 29, 733-751. Hoefen et al. (2003), Science, 302, 627-630. Panieri et al. (2010), Geobiology, 8, 101-111. Pondrelli et al. (2011), EPSL, 304, 511-519. Rossi et al. (2008), JGR, 113(8).
NASA Astrophysics Data System (ADS)
Arling, J.-H.; Gerhardt, M.; Gößling, C.; Gehre, D.; Klingenberg, R.; Kröninger, K.; Nitsch, C.; Quante, T.; Rohatsch, K.; Tebrügge, J.; Temminghoff, R.; Theinert, R.; Zatschler, S.; Zuber, K.
2017-11-01
The COBRA collaboration searches for neutrinoless double beta-decay (0νββ-decay) using CdZnTe semiconductor detectors with a coplanar-grid readout and a surrounding guard-ring structure. The operation of the COBRA demonstrator at the Gran Sasso underground laboratory (LNGS) indicates that alpha-induced lateral surface events are the dominant source of background events. By instrumenting the guard-ring electrode it is possible to suppress this type of background. In laboratory measurements this method achieved a suppression factor of alpha-induced lateral surface events of 5300+2660-1380, while retaining (85.3 ±0.1%) of gamma events occurring in the entire detector volume. This suppression is superior to the pulse-shape analysis methods used so far in COBRA by three orders of magnitude.
A review of the alpha-1 foundation: its formation, impact, and critical success factors.
Walsh, John W; Snider, Gordon L; Stoller, James K
2006-05-01
Patient-advocacy organizations have proliferated because they can be an effective method to advance research and clinical care for those with the index condition, and can produce substantial benefits for the affected community, especially when the condition is uncommon. To clarify critical success factors in organizing a patient-advocacy organization and to provide a blueprint for others, including the respiratory-care advocacy community, this report examines features of one highly successful organization, the Alpha-1 Foundation, which is committed to helping those with the genetic condition alpha-1 antitrypsin deficiency. Features of the Alpha-1 Foundation that underlie its success include: consistently creating partnerships with key stakeholders, including the scientific and clinical communities, government, and pharmaceutical manufacturers; bringing passion to the cause (eg, by assuring that organizational leadership is provided by individuals affected by alpha-1 antitrypsin deficiency); and developing strategic business partnerships, as with a company that administers alpha-1 antitrypsin treatment (so-called intravenous augmentation therapy) and employs individuals with alpha-1 antitrypsin deficiency. Funds allocated by the company help to underwrite the foundation's research-funding commitment. The foundation also recruits and retains talent, including alpha-1 patients, to leadership roles (eg, on the board of directors) and has a voluntary group of committed scientists and clinicians. We believe that attention to these factors can help assure the success of patient-advocacy groups.
Sufficient and necessary condition of separability for generalized Werner states
DOE Office of Scientific and Technical Information (OSTI.GOV)
Deng Dongling; Chen Jingling
2009-02-15
In a celebrated paper [Optics Communications 179, 447, 2000], A.O. Pittenger and M.H. Rubin presented for the first time a sufficient and necessary condition of separability for the generalized Werner states. Inspired by their ideas, we generalized their method to a more general case. We obtain a sufficient and necessary condition for the separability of a specific class of N d-dimensional system (qudits) states, namely special generalized Werner state (SGWS): W{sup [d{sup N}]}(v)=(1-v)(I{sup (N)})/(d{sup N}) +v|{psi}{sub d}{sup N}><{psi}{sub d}{sup N}|, where |{psi}{sub d}{sup N}>={sigma}{sub i=0}{sup d-1}{alpha}{sub i}|i...i> is an entangled pure state of N qudits system and {alpha}{sub i} satisfiesmore » two restrictions: (i) {sigma}{sub i=0}{sup d-1}{alpha}{sub i}{alpha}{sub i}*=1; (ii) Matrix 1/d (I{sup (1)}+T{sigma}{sub i{ne}}{sub j}{alpha}{sub i}|i>
Continuous extraovular administration of prostaglandin F2alpha for midtrimester abortion.
Lauersen, N H; Wilson, K H
1974-09-15
Midtrimester abortion was successfully induced in 74 of 76 patients by a continuous extraovular administration of (PGF2alpha) prostaglandin F2alpha via a constant-infusion pump. 2 patients in the 13th-14th weeks of gestation failed to abort despite good uterine activity. The mean abortion time for successful inductions was 16.21 hours. Parous patients aborted somewhat faster than nulliparous patients, but the difference was not statistically significant. All patients were monitored throughout the abortion procedure, and uterine activity was calculated and analyzed. Uterine activity developed within 15 minutes of PGF2alpha instillation and showed the characteristic uterine response to PGs with a sharp rise in intrauterine tonus. The gastrointestinal side effects in this series were much less than those reported for intraamniotic instillation of PG, and there was good patient tolerance of the procedure. The main complication of extraovular administration of PGF2alpha for midtrimester abortion was endometritis, which occurred in 7 patients. The patients who developed endometritis had, as a group, longer abortion times (mean=28 hours). 3 patients with severe preeclampsia and intrauterine death in the third trimester also had successfully induced labor with extraovular administration of PGF2alpha. The method of PGF2alpha administration in the series was found to have a high success rate, good patient tolerance, and fewer side effects than when abortion was induced by intraamniotic instillation of PGF2alpha.
Toda, Tatsushi
2009-11-01
Hypoglycosylation and reduced laminin-binding activity of alpha-dystroglycan are common characteristics of dystroglycanopathy, which is a group of congenital and limb-girdle muscular dystrophies. We previously identified the genes for Fukuyama congenital muscular dystrophy (FCMD) and muscle-eye-brain disease (MEB). FCMD, caused by a mutation in the fukutin gene, is a severe form of dystroglycanopathy. Knock-in mice carrying the founder retrotransposal insertion exhibited hypoglycosylated alpha-dystroglycan; however, no signs of muscular dystrophy were observed. More sensitive methods detected minor levels of intact alpha-dystroglycan, and solid-phase assays determined laminin binding levels to be approximately 50% of normal. In contrast, intact alpha-dystroglycan is undetectable in the dystrophic Large mouse, and laminin-binding activity is markedly reduced. These data indicate that a small amount of intact alpha-dystroglycan is sufficient to maintain muscle cell integrity in knock-in mice, suggesting that the treatment of dystroglycanopathies might not require the full recovery of glycosylation. Transfer of fukutin into knock-in mice restored glycosylation of alpha-dystroglycan. Transfer of LARGE produced laminin-binding forms of alpha-dystroglycan in both knock-in mice and the POMGnT1 mutant mouse. These data suggest that even partial restoration of alpha-dystroglycan glycosylation and laminin-binding activity by replacing or augmenting glycosylation-related genes might effectively deter dystroglycanopathy progression and thus provide therapeutic benefits.
Chen, Xiaowen; Zhao, Luqian; Qin, Hongran; Zhao, Meijia; Zhou, Yirui; Yang, Shuqiang; Su, Xu; Xu, Xiaohua
2014-05-01
The aim of this work was to develop a method to provide rapid results for humans with internal radioactive contamination. The authors hypothesized that valuable information could be obtained from gas proportional counter techniques by screening urine samples from potentially exposed individuals rapidly. Recommended gross alpha and beta activity screening methods generally employ gas proportional counting techniques. Based on International Standards Organization (ISO) methods, improvements were made in the evaporation process to develop a method to provide rapid results, adequate sensitivity, and minimum sample preparation and operator intervention for humans with internal radioactive contamination. The method described by an American National Standards Institute publication was used to calibrate the gas proportional counter, and urine samples from patients with or without radionuclide treatment were measured to validate the method. By improving the evaporation process, the time required to perform the assay was reduced dramatically. Compared with the reference data, the results of the validation samples were very satisfactory with respect to gross-alpha and gross-beta activities. The gas flow proportional counting method described here has the potential for radioactivity monitoring in the body. This method was easy, efficient, and fast, and its application is of great utility in determining whether a sample should be analyzed by a more complicated method, for example radiochemical and/or γ-spectroscopy. In the future, it may be used commonly in medical examination and nuclear emergency treatment.Health Phys. 106(5):000-000; 2014.
Influence of solvents on the habit modification of alpha lactose monohydrate single crystals
NASA Astrophysics Data System (ADS)
Parimaladevi, P.; Srinivasan, K.
2013-02-01
Restricted evaporation of solvent method was adopted for the growth of alpha lactose monohydrate single crystals from different solvents. The crystal habits of grown crystals were analysed. The form of crystallization was confirmed by powder x-ray diffraction analysis. Thermal behaviour of the grown crystals was studied by using differential scanning calorimetry.
Non-linear vacuum polarization in strong fields
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gyulassy, M.
1981-07-01
The Wichmann-Kroll formalism for calculating the vacuum polarization density to first order in ..cap alpha.. but to all orders in Z..cap alpha.. is derived. The most essential quantity is shown to be the electrons Green's function in these calculations. The method of constructing that Green's function in the field of finite radius nuclei is then presented.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Oliveira Lopes, Carlos; Callera, Fernando, E-mail: fcallera@gmail.com
Purpose: To investigate the effect of radiotherapy (RT) on serum levels of interleukin-2 (IL-2), IL-4, IL-5, IL-6, tumor necrosis factor alpha (TNF-{alpha}), macrophage inflammatory protein-1-alpha (MIP-1-{alpha}) and leukemia inhibitory factor (LIF) in patients with prostate cancer. Methods and Materials: Forty eight patients with prostate cancer received three-dimensional conformal blocking radiation therapy with a linear accelerator. IL-2, IL-4, IL-5, IL-6, TNF-{alpha}, MIP-1-{alpha}, and LIF levels were measured by the related immunoassay kit 1 day before the beginning of RT and during RT at days 15 and 30. Results: The mean IL-2 values were elevated before and during the RT in contrastmore » with those of IL-4, IL-5, IL-6, TNF-{alpha}, MIP-1-{alpha}, and LIF, which were within the normal range under the same conditions. Regarding markers IL-2, IL-4, IL-5, TNF-{alpha}, MIP-1-{alpha}, and LIF, comparisons among the three groups (before treatment and 15 and 30 days during RT) did not show significant differences. Although values were within the normal range, there was a significant rise in IL-6 levels at day 15 of RT (p = 0.0049) and a decline at day 30 to levels that were similar to those observed before RT. Conclusions: IL-6 appeared to peak after 15 days of RT before returning to pre-RT levels. In contrast, IL-2, IL-4, IL-5, TNF-{alpha}, MIP-1-{alpha}, and LIF levels were not sensitive to irradiation. The increased levels of IL-6 following RT without the concurrent elevation of other cytokines involved in the acute phase reaction did not suggest a classical inflammatory response to radiation exposure. Further studies should be designed to elucidate the role of IL-6 levels in patients with prostate cancer treated with RT.« less
Nogae, C; Makino, N; Hata, T; Nogae, I; Takahashi, S; Suzuki, K; Taniguchi, N; Yanaga, T
1995-10-01
We investigated the effects of pretreatment with interleukin (IL)-1 alpha on the expression of manganous (Mn) superoxide dismutase (SOD) mRNA and reperfusion-induced arrhythmias and the size of myocardial infarct in rats. Male Wistar rats received 10 mg intraperitoneal injections of human recombinant IL-1 alpha. Their hearts were thereafter isolated at 6, 12, 24, 36 h. A Northern analysis showed that Mn-SOD mRNA was mainly expressed in the heart and slightly in kidney, but not in any other organs. The expression of Mn-SOD mRNA peaked at 6 h after the injection of IL-1 alpha. The Mn-SOD protein content was most increased 12 h after injection. In the isolated heart model, the rats were pretreated with IL-1 alpha 24 h earlier and their hearts were perfused by the Langendorff method. After 20 min of ischemia which was induced by a ligation of a coronary artery, reperfusion-induced arrhythmias were observed. There were no significant differences in the incidence of ventricular arrhythmias between the IL-1 alpha pretreated and the untreated hearts. IL-1 alpha pretreatment significantly reduced the mean duration of the ventricular arrhythmias and also delayed the onset of arrhythmias. The effect of IL-1 alpha pretreatment was also investigated in a 30-min model of ischemia followed by a 3-min reperfusion in anesthetized rats. The infarct size expressed as a percentage of the area at risk was significantly reduced in the IL-1 alpha pretreated hearts compared with the untreated hearts. The left ventricular systolic pressure increased significantly in rat hearts pretreated with IL-1 alpha. Our results therefore showed that the pretreatment with IL-1 alpha induced the overexpression of Mn-SOD mRNA in the rat hearts and also suggested that pretreatment with IL-1 alpha 24 h before ischemia reduced the risk of ischemia-reperfusion injury.
Reduction of Radon Progeny in Indoor Air.
1986-03-01
arises from indoor radon is due * 4 to inhalation of the short-lived radon daughters Ra-A, Ra-B, and Ra-C. These decay products are formed from the alpha...concentrations of radon daughters 40 ’ in an air sample from the gross alpha counting of a filter 50 ’ in accordance with the modified Tsivoglou method. 60 ’ 70...8217 The modified Tsivoglou method may be found in " Measurement 80 ’ of Radon Daughters in Air," Health Physics, 23, : pp7S3-789 90 ’ (19). 95 100 The
NASA Technical Reports Server (NTRS)
Freier, P. S.; Atwater, T. W.
1985-01-01
A determination of primary energy is required in order to study the energy dependence of meson multiplicity in A-A collisions in cosmic rays. Various procedures which estimate the energy of a primary nucleus from its interaction were investigated. An average of two methods were used, one using the pions and wounded protons and the other using spectator protons and alpha particles. The high P sub T tail observed for Z = 2 fragments requires a modification of the latter method.
NASA Astrophysics Data System (ADS)
Yoshida, J.; Kinbara, S.; Mishina, A.; Nakazawa, K.; Soe, M. K.; Theint, A. M. M.; Tint, K. T.
2017-03-01
A new scanning system named "Vertex picker" has been developed to rapid collect alpha decay events, which are calibration sources for the range-energy relation in nuclear emulsion. A computer-controlled optical microscope scans emulsion layers exhaustively, and a high-speed and high-resolution camera takes their micrographs. A dedicated image processing picks out vertex-like shapes. Practical operations of alpha decay search were demonstrated by emulsion sheets of the KEK-PS E373 experiment. Alpha decays of nearly 28 events were detected in eye-check work on a PC monitor per hour. This yield is nearly 20 times more effective than that by the conventional eye-scan method. The speed and quality is acceptable for the coming new experiment, J-PARC E07.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ji, Long; Zhang, Shu; Chen, YuPeng
We report on a study of GS 1826-238 using all available Rossi X-Ray Timing Explorer observations, concentrating on the behavior of the hard X-rays during type-I bursts. We find a hard X-ray shortage at 30-50 keV prompted by the shower of soft X-rays coming from type-I bursts. This shortage happens with a time delay after the peak of the soft flux of 3.6 ± 1.2 s. The behavior of hard X-rays during bursts indicates cooling and reheating of the corona, during which a large amount of energy is required. We speculate that this energy originates from the feedback of themore » type-I bursts to the accretion process, resulting in a rapid temporary increase of the accretion rate.« less
The Successful Synergy of Swift and Fermi/GBM in Magnetars
NASA Technical Reports Server (NTRS)
Kouveliotou, Chryssa
2011-01-01
The magnetar rate of discovery has increased dramatically in the last decade. Five sources were discovered in the last three years alone as a result of the very efficient synergy among three X- and .gamma-ray instruments on NASA satellites: the Swift/Burst Alert Telescope (BAT), the Fermi/Gamma ray Burst Monitor (GBM), and the Rossi X-Ray Timing Explorer; RXTE/Proportional Counter Array (PCA). To date, there are approx. 25 magnetar candidates, of which two are (one each) in the Large and Small Magellanic Cloud and the rest reside on the Galactic plane of our Milky Way. I will discuss here the main properties of the Magnetar Population and the common projects that can be achieved with the synergy of Swift and GBM.
Delta-ray Production in MCNP 6.2.0
NASA Astrophysics Data System (ADS)
Anderson, C.; McKinney, G.; Tutt, J.; James, M.
Secondary electrons in the form of delta-rays, also referred to as knock-on electrons, have been a feature of MCNP for electron and positron transport for over 20 years. While MCNP6 now includes transport for a suite of heavy-ions and charged particles from its integration with MCNPX, the production of delta-rays was still limited to electron and positron transport. In the newest release of MCNP6, version 6.2.0, delta-ray production has now been extended for all energetic charged particles. The basis of this production is the analytical formulation from Rossi and ICRU Report 37. This paper discusses the MCNP6 heavy charged-particle implementation and provides production results for several benchmark/test problems.
Accreting Millisecond Pulsars: Neutron Star Masses and Radii
NASA Technical Reports Server (NTRS)
Strohmayer, Tod
2004-01-01
High amplitude X-ray brightness oscillations during thermonuclear X-ray bursts were discovered with the Rossi X-ray Timing Explorer (RXTE) in early 1996. Spectral and timing evidence strongly supports the conclusion that these oscillations are caused by rotational modulation of the burst emission and that they reveal the spin frequency of neutron stars in low mass X-ray binaries. The recent discovery of X-ray burst oscillations from two accreting millisecond pulsars has confirmed this basic picture and provided a new route to measuring neutron star properties and constraining the dense matter equation of state. I will briefly summarize the current observational understanding of accreting millisecond pulsars, and describe recent attempts to determine the mass and radius of the neutron star in XTE J1814-338.
A NON-PRE DOUBLE-PEAKED BURST FROM 4U 1636-536: EVIDENCE FOR BURNING FRONT PROPAGATION
NASA Technical Reports Server (NTRS)
Bhattacharyya, Sudip; Strohmayer, Tod E.
2005-01-01
We analyse Rossi X-ray Timing Explorer (RXTE) Proportional Counter Array (PCA) data of a double-peaked burst from the low mass X-ray binary (LMXB) 4U 1636-536 that shows no evidence for photospheric radius expansion (PRE). We find that the X-ray emitting area on the star increases with time as the burst progresses, even though the photosphere does not expand. We argue that this is a strong indication of thermonuclear flame spreading on the stellar surface during such bursts. We propose a model for such double-peaked bursts, based on thermonuclear flame spreading, that can qualitatively explain their essential features, as well as the rarity of these bursts.
Catching Up on State Transitions in Cygnus X-1
NASA Technical Reports Server (NTRS)
Boeck, Moritz; Hanke, Manfred; Wilms, Joern; Pirner, Stefan; Grinberg, Victoria; Markoff, Sera; Pottschmidt, Katja; Nowak, Michael A.; Pooley, Guy
2008-01-01
In 2005 February we observed Cygnus X-1 over a period of 10 days quasi-continuously with the Rossi X-ray Timing Explorer and the Ryle telescope. We present the results of the spectral and timing analysis on a timescale of 90 min and show that the behavior of Cyg X-1 is similar to that found during our years long monitoring campaign. As a highlight we present evidence for a full transition from the hard to the soft state that happened during less than three hours. The observation provided a more complete picture of a state transition than before, especially concerning the evolution of the time lags, due to unique transition coverage and analysis with high time resolution.
Equol an isoflavonoid: potential for improved prostate health, in vitro and in vivo evidence
2011-01-01
Background To determine: in vitro binding affinity of equol for 5alpha-dihydrotestosterone (5alpha-DHT), in vitro effects of equol treatment in human prostate cancer (LNCap) cells, and in vivo effects of equol on rat prostate weight and circulating levels of sex steroid hormones. Methods First, in vitro equol binding affinity for 5alpha-DHT was determined using 14C5alpha-DHT combined with cold 5alpha-DHT (3.0 nM in all samples). These steroids were incubated with increasing concentrations of equol (0-2,000 nM) and analyzed by Sephadex LH-20 column chromatography. 14C5alpha-DHT peak/profiles were determined by scintillation counting of column fractions. Using the 14C5alpha-DHT peak (0 nM equol) as a reference standard, a binding curve was generated by quantifying shifts in the 14C5alpha-DHT peaks as equol concentrations increased. Second, equol's in vitro effects on LNCap cells were determined by culturing cells (48 hours) in the presence of increasing concentrations of dimethyl sulfoxide (DMSO) (vehicle-control), 5alpha-DHT, equol or 5alpha-DHT+equol. Following culture, prostate specific antigen (PSA) levels were quantified via ELISA. Finally, the in vivo effects of equol were tested in sixteen male Long-Evans rats fed a low isoflavone diet. From 190-215 days, animals received 0.1cc s.c. injections of either DMSO-control vehicle (n = 8) or 1.0 mg/kg (body weight) of equol (in DMSO) (n = 8). At 215 days, body and prostate weights were recorded, trunk blood was collected and serum assayed for luteinizing hormone (LH), 5alpha-DHT, testosterone and 17beta-estradiol levels. Results Maximum and half maximal equol binding to 5alpha-DHT occurred at approximately 100 nM and 4.8 nM respectively. LNCap cells cultured in the presence of 5alpha-DHT significantly increased PSA levels. However, in the presence of 5alpha-DHT+equol, equol blocked the significant increases in PSA levels from LNCap cells. In vivo equol treatment significantly decreased rat prostate weights and serum 5alpha-DHT levels but did not alter LH, testosterone, and estradiol levels. Conclusions Equol administration appears to have potential beneficial effects for prostate health and other 5alpha-DHT mediated disorders. Equol administration: reduces PSA levels from LNCap cells under 5alpha-DHT stimulation, decreases rat prostate size, decreases serum 5alpha-DHT levels and androgen hormone action, while not altering other circulating sex steroids or LH levels. PMID:21232127
AlphaSpace: Fragment-Centric Topographical Mapping To Target Protein–Protein Interaction Interfaces
2016-01-01
Inhibition of protein–protein interactions (PPIs) is emerging as a promising therapeutic strategy despite the difficulty in targeting such interfaces with drug-like small molecules. PPIs generally feature large and flat binding surfaces as compared to typical drug targets. These features pose a challenge for structural characterization of the surface using geometry-based pocket-detection methods. An attractive mapping strategy—that builds on the principles of fragment-based drug discovery (FBDD)—is to detect the fragment-centric modularity at the protein surface and then characterize the large PPI interface as a set of localized, fragment-targetable interaction regions. Here, we introduce AlphaSpace, a computational analysis tool designed for fragment-centric topographical mapping (FCTM) of PPI interfaces. Our approach uses the alpha sphere construct, a geometric feature of a protein’s Voronoi diagram, to map out concave interaction space at the protein surface. We introduce two new features—alpha-atom and alpha-space—and the concept of the alpha-atom/alpha-space pair to rank pockets for fragment-targetability and to facilitate the evaluation of pocket/fragment complementarity. The resulting high-resolution interfacial map of targetable pocket space can be used to guide the rational design and optimization of small molecule or biomimetic PPI inhibitors. PMID:26225450
Mikkelsen, Lise Munch; Hernáiz, María José; Martín-Pastor, M; Skrydstrup, Troels; Jiménez-Barbero, Jesús
2002-12-18
The conformational properties of the C-glycosyl analogue of the core trisaccharide alpha-D-Man-(1 --> 3)-[alpha-D-Man-(1 --> 6)]-D-Man in solution have been carefully analyzed by a combination of NMR spectroscopy and time-averaged restrained molecular dynamics. It has been found that both the alpha-1,3- and the alpha-1,6-glycosidic linkages show a major conformational averaging. Unusual Phi ca. 60 degrees orientations for both Phi torsion angles are found. Moreover, a major conformational distinction between the natural compound and the glycomimetic affects to the behavior of the omega(16) torsion angle around the alpha-1 --> 6-linkage. Despite this increased flexibility, the C-glycosyl analogue is recognized by three mannose binding lectins, as shown by NMR (line broadening, TR-NOE, and STD) and surface plasmon resonance (SPR) methods. Moreover, a process of conformational selection takes place, so that these lectins probably bind the glycomimetic similarly to the way they recognize the natural analogue. Depending upon the architecture and extension of the binding site of the lectin, loss or gain of binding affinity with respect to the natural analogue is found.
Influence of amorphous content on compaction behaviour of anhydrous alpha-lactose.
Ziffels, S; Steckel, H
2010-03-15
Modified lactoses are widely used as filler-binders in direct compression of tablets. Until today, little about the compaction behaviour of anhydrous alpha-lactose is known. In this study, a new method to prepare anhydrous alpha-lactose from alpha-lactose monohydrate by desiccation with heated ethanol was evaluated and the influence of amorphous content in the lactose powder prior to modification on powder properties, compaction behaviour and storage stability was determined. The modification process led to anhydrous alpha-lactose with decreased bulk and tapped density, increased flow rate and significantly higher specific surface area. Due to the higher specific surface area, the compaction behaviour of the anhydrous alpha-lactose was found to be significantly better than the compaction behaviour of powder blends consisting of alpha-lactose monohydrate and amorphous lactose. An influence of the amorphous content prior to modification could be observed only at higher compaction forces. In general, tablets of modified powders needed longer time to disintegrate directly after compression. However, the storage stability of modified tablets was found to be better compared to the amorphous-crystalline tablets which were influenced by storage conditions, initial crushing strength as well as amorphous content due to the re-crystallization of amorphous lactose during storage. 2009 Elsevier B.V. All rights reserved.
Integrin distributions in renal cell carcinomas of various grades of malignancy.
Korhonen, M.; Laitinen, L.; Ylänne, J.; Koukoulis, G. K.; Quaranta, V.; Juusela, H.; Gould, V. E.; Virtanen, I.
1992-01-01
We studied 41 renal cell carcinomas, classified according to histologic grades G1 through G3, by indirect immunofluorescence microscopy using a panel of monoclonal antibodies (MAb) against various integrin subunits, and the basement membrane (BM) components laminin and collagen type IV. Selected cases also were immunostained using the avidin-biotin-complex method. The alpha 3 and beta 1 integrin subunits were detected in tumor cells of all the carcinomas. All G1 carcinomas, like normal tubular epithelial cells, expressed the alpha 6 subunit, whereas it was lacking in 20% and 40% of G2 and G3 carcinomas, respectively. Furthermore, when alpha 6 was expressed, a lack of basally polarized organization of the subunit, coupled with disorganization of the BM components, correlated with histologic grade. Another feature that appeared to characterize the more anaplastic tumors was their high level (80%) of the alpha v subunit expression as compared with its absence in the G1 carcinomas. Stromal myofibroblasts, identified by double-labeling with anti-myosin, were often characterized by the expression of the alpha 1, alpha 3, alpha 5 and beta 1 subunits. These results indicate that changes in integrin expression in renal cell carcinomas may be correlated with their degree of histologic malignancy. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:1443050
Patterns of cortisol and alpha-amylase reactivity to psychosocial stress in maltreated women
Mielock, Alyssa S.; Morris, Matthew C.; Rao, Uma
2016-01-01
Background Childhood maltreatment can trigger enduring changes in major stress response systems, particularly in the context of major depressive disorder (MDD). However, the relative impact of maltreatment versus MDD on hypothalamic-pituitary-adrenal axis and sympathetic-adrenal-medullary system stress reactivity is not well understood. Method This study examined salivary cortisol and alpha-amylase responses to the Trier Social Stress Test (TSST) in 26 maltreated (15 with current MDD) and 26 non-maltreated (17 with current MDD) women. Results Maltreated women showed greater anticipatory cortisol reactivity during the TSST protocol compared to non-maltreated women. Maltreated women also showed rapid deceleration in cortisol levels. Whereas non-maltreated women showed initial declines in alpha-amylase levels but rapidly increasing alpha-amylase levels during the TSST protocol, maltreated women did not exhibit changes in alpha-amylase levels during the TSST protocol. Contrary to expectation, MDD did not impact cortisol or alpha-amylase responses. Limitations The present study is limited by retrospective report of childhood maltreatment, cross-sectional design, and modest sample sizes. Conclusions These findings suggest that childhood maltreatment plays a greater role driving alterations in cortisol and alpha-amylase stress reactivity than MDD. Understanding the biological embedding of maltreatment is critical for elucidating mechanisms linking these experiences to risk for negative mental and physical health outcomes. PMID:27875756
Ancient roots for polymorphism at the HLA-DQ. alpha. locus in primates
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gyllensten, U.B.; Erlich, H.A.
1989-12-01
The genes encoding the human histocompatibility antigens (HLA) exhibit a remarkable degree of polymorphism as revealed by immunologic and molecular analyses. This extensive sequence polymorphism either may have been generated during the lifetime of the human species or could have arisen before speciation and been maintained in the contemporary human population by selection or, possibly, by genetic drift. These two hypotheses were examined using the polymerase chain reaction method to amplify polymorphic sequences from the DQ{alpha} locus, as well as the DX{alpha} locus, an homologous but nonexpressed locus, in a series of primates that diverged at known times. In general,more » the amino acid sequence of a specific human DQ{alpha} allelic type is more closely related to its chimpanzee or gorilla counterpart than to other human DQ{alpha} alleles. Phylogenetic analysis of the silent nucleotide position changes shows that the similarity of allelic types between species is due to common ancestry rather than convergent evolution. Thus, most of the polymorphism at the DQ{alpha} locus in the human species was already present at least 5 million years ago in the ancestral species that gave rise to the chimpanzee, gorilla, and human lineages. However, one of the DQ{alpha} alleles may have arisen after speciation by recombination between two ancestral alleles.« less
NASA Technical Reports Server (NTRS)
Mcintosh, P. S.
1975-01-01
Solar activity during the period October 28, 1964 through August 27, 1965 is presented in the form of charts for each solar rotation constructed from observations made with the chromospheric H-alpha spectra line. These H-alpha synoptic charts are identical in format and method of construction to those published for the period of Skylab observations. The sunspot minimum marking the start of Solar Cycle 20 occurred in October, 1964; therefore, charts represent solar activity during the first year of this solar cycle.
Mozhaev, V V; Sergeeva, M V; Belova, A B; Khmelnitsky, Y L
1990-03-25
Inactivation of alpha-chymotrypsin in aqueous solutions of alcohols and diols proceeds both reversibly and irreversibly. Reversible loss of the specific enzyme activity results from conformational changes (unfolding) of the enzyme detected by fluorescence spectroscopy. Multipoint covalent attachment to the matrix of polyacryl-amide gel by copolymerization method stabilizes alpha-chymotrypsin from denaturation by alcohols, the stabilizing effect increasing with the number of bonds between the protein and the support. Immobilization protects the enzyme also from irreversible inactivation by organic solvents resulting from bimolecular aggregation and autolysis.
Steroid determination in fish plasma using capillary electrophoresis.
Bykova, Liliya; Archer-Hartmann, Stephanie A; Holland, Lisa A; Iwanowicz, Luke R; Blazer, Vicki S
2010-09-01
A capillary separation method that incorporates pH-mediated stacking is employed for the simultaneous determination of circulating steroid hormones in plasma from Perca flavescens (yellow perch) collected from natural aquatic environments. The method can be applied to separate eight steroid standards: progesterone, 17alpha,20beta-dihydroxypregn-4-en-3-one, 17alpha-hydroxyprogesterone, testosterone, estrone, 11-ketotestosterone, ethynyl estradiol, and 17beta-estradiol. Based on screening of plasma, the performance of the analytical method was determined for 17alpha,20beta-dihydroxypregn-4-en-3-one, testosterone, 11-ketotestosterone, and 17beta-estradiol. The within-day reproducibility in migration time for these four steroids in aqueous samples was < or =2%. Steroid quantification was accomplished using a calibration curve obtained with external standards. Plasma samples from fish collected from the Choptank and Severn Rivers, Maryland, USA, stored for up to one year were extracted with ethyl acetate and then further processed with anion exchange and hydrophobic solid phase extraction cartridges. The recovery of testosterone and 17beta-estradiol from yellow perch plasma was 84 and 85%, respectively. Endogenous levels of testosterone ranged from 0.9 to 44 ng/ml, and when detected 17alpha,20beta-dihydroxypregn-4-en-3-one ranged from 5 to 34 ng/ml. The reported values for testosterone correlated well with the immunoassay technique. Endogenous concentrations of 17beta-estradiol were < or =1.7 ng/ml. 11-Ketotestosterone was not quantified because of a suspected interferant. Higher levels of 17alpha,20beta-dihydroxypregn-4-en-3-one were found in male and female fish in which 17beta-estradiol was not detected. Monitoring multiple steroids can provide insight into hormonal fluctuations in fish. Copyright 2010 SETAC.
Alpha Rhythms in Audition: Cognitive and Clinical Perspectives
Weisz, Nathan; Hartmann, Thomas; Müller, Nadia; Lorenz, Isabel; Obleser, Jonas
2011-01-01
Like the visual and the sensorimotor systems, the auditory system exhibits pronounced alpha-like resting oscillatory activity. Due to the relatively small spatial extent of auditory cortical areas, this rhythmic activity is less obvious and frequently masked by non-auditory alpha-generators when recording non-invasively using magnetoencephalography (MEG) or electroencephalography (EEG). Following stimulation with sounds, marked desynchronizations can be observed between 6 and 12 Hz, which can be localized to the auditory cortex. However knowledge about the functional relevance of the auditory alpha rhythm has remained scarce so far. Results from the visual and sensorimotor system have fuelled the hypothesis of alpha activity reflecting a state of functional inhibition. The current article pursues several intentions: (1) Firstly we review and present own evidence (MEG, EEG, sEEG) for the existence of an auditory alpha-like rhythm independent of visual or motor generators, something that is occasionally met with skepticism. (2) In a second part we will discuss tinnitus and how this audiological symptom may relate to reduced background alpha. The clinical part will give an introduction into a method which aims to modulate neurophysiological activity hypothesized to underlie this distressing disorder. Using neurofeedback, one is able to directly target relevant oscillatory activity. Preliminary data point to a high potential of this approach for treating tinnitus. (3) Finally, in a cognitive neuroscientific part we will show that auditory alpha is modulated by anticipation/expectations with and without auditory stimulation. We will also introduce ideas and initial evidence that alpha oscillations are involved in the most complex capability of the auditory system, namely speech perception. The evidence presented in this article corroborates findings from other modalities, indicating that alpha-like activity functionally has an universal inhibitory role across sensory modalities. PMID:21687444
Terdale, Santosh S; Dagade, Dilip H; Patil, Kesharsingh J
2007-12-06
Data on osmotic coefficients have been obtained for a binary aqueous solution of two drugs, namely, promazine hydrochloride (PZ) and chlorpromazine hydrochloride (CPZ) using a vapor pressure osmometer at 298.15 K. The observed critical micelle concentration (cmc) agrees excellently with the available literature data. The measurements are extended to aqueous ternary solutions containing fixed a concentration of alpha-cyclodextrin (alpha-CD) of 0.1 mol kg(-1) and varied concentrations (approximately 0.005-0.2 mol kg(-1)) of drugs at 298.15 K. It has been found that the cmc values increase by the addition of alpha-CD. The mean molal activity coefficients of the ions and the activity coefficient of alpha-CD in binary as well as ternary solutions were obtained, which have been further used to calculate the excess Gibbs free energies and transfer Gibbs free energies. The lowering of the activity coefficients of ions and of alpha-CD is attributed to the existence of host-guest (inclusion)-type complex equilibria. It is suggested that CPZ forms 2:1 and 1:1 complexed species with alpha-CD, while PZ forms only 1:1 complexed species. The salting constant (ks) values are determined at 298.15 K for promazine-alpha-CD and chlorpromazine-alpha-CD complexes, respectively, by following the method based on the application of the McMillan-Mayer theory of virial coefficients to transfer free energy data. It is noted that the presence of chlorine in the drug molecule imparts better complexing capacity, the effect of which gets attenuated as a result of hydrophobic interaction. The results are discussed from the point of view of associative equilibria before the cmc and complexed equilibria for binary and ternary solutions, respectively.
Quantification of active principles and pigments in leaf extracts of Isatis tinctoria by HPLC/UV/MS.
Mohn, Tobias; Potterat, Olivier; Hamburger, Matthias
2007-02-01
An HPLC method has been developed and validated for the quantification of the pharmacologically active principles tryptanthrin (1), 1,3-dihydro-3-[(4-hydroxy-3,5-dimethoxyphenyl)methylene]-2 H-indol-2-one (indolinone) (3), indirubin (4), alpha-linolenic acid (2), and indigo (5), an isomer of indirubin, in extracts from the traditional anti-inflammatory plant Isatis tinctoria (woad). The chromatographic separation was performed on a C-18 column with a linear gradient of acetonitrile in water containing 0.1% formic acid. The method combines UV and electrospray MS detection in the positive ion mode for the detection of the alkaloids, with a switch to the negative mode for the analysis of alpha-linolenic acid. The method was applied to the analysis of woad extracts obtained by supercritical fluid (SFE) CO2 extraction, and by pressurized liquid extraction (PLE) with dichloromethane and methanol, respectively. While the highest concentration of alpha-linolenic acid was found in the SFE extract (7.43%), the concentrations of tryptanthrin , indolinone, indirubin and indigo were the highest in the dichloromethane extract (0.30, 0.035, 2.48 and 0.84%, respectively). Compound 3 was not detected in the methanolic extract and only traces of compounds 1, 4 and 5 and low amount of alpha-linolenic acid (0.39%) were present in this extract.
Force-free magnetic fields - The magneto-frictional method
NASA Technical Reports Server (NTRS)
Yang, W. H.; Sturrock, P. A.; Antiochos, S. K.
1986-01-01
The problem under discussion is that of calculating magnetic field configurations in which the Lorentz force j x B is everywhere zero, subject to specified boundary conditions. We choose to represent the magnetic field in terms of Clebsch variables in the form B = grad alpha x grad beta. These variables are constant on any field line so that each field line is labeled by the corresponding values of alpha and beta. When the field is described in this way, the most appropriate choice of boundary conditions is to specify the values of alpha and beta on the bounding surface. We show that such field configurations may be calculated by a magneto-frictional method. We imagine that the field lines move through a stationary medium, and that each element of magnetic field is subject to a frictional force parallel to and opposing the velocity of the field line. This concept leads to an iteration procedure for modifying the variables alpha and beta, that tends asymptotically towards the force-free state. We apply the method first to a simple problem in two rectangular dimensions, and then to a problem of cylindrical symmetry that was previously discussed by Barnes and Sturrock (1972). In one important respect, our new results differ from the earlier results of Barnes and Sturrock, and we conclude that the earlier article was in error.
Preparation of alpha-emitting nuclides by electrodeposition
NASA Astrophysics Data System (ADS)
Lee, M. H.; Lee, C. W.
2000-06-01
A method is described for electrodepositing the alpha-emitting nuclides. To determine the optimum conditions for plating plutonium, the effects of electrolyte concentration, chelating reagent, current, pH of electrolyte and the time of plating on the electrodeposition were investigated on the base of the ammonium oxalate-ammonium sulfate electrolyte containing diethyl triamino pentaacetic acid. An optimized electrodeposition procedure for the determination of plutonium was validated by application to environmental samples. The chemical yield of the optimized method of electrodeposition step in the environmental sample was a little higher than that of Talvitie's method. The developed electrodeposition procedure in this study was applied to determine the radionuclides such as thorium, uranium and americium that the electrodeposition yields were a little higher than those of the conventional method.
Yang, Jian-Yi; Peng, Zhen-Ling; Yu, Zu-Guo; Zhang, Rui-Jie; Anh, Vo; Wang, Desheng
2009-04-21
In this paper, we intend to predict protein structural classes (alpha, beta, alpha+beta, or alpha/beta) for low-homology data sets. Two data sets were used widely, 1189 (containing 1092 proteins) and 25PDB (containing 1673 proteins) with sequence homology being 40% and 25%, respectively. We propose to decompose the chaos game representation of proteins into two kinds of time series. Then, a novel and powerful nonlinear analysis technique, recurrence quantification analysis (RQA), is applied to analyze these time series. For a given protein sequence, a total of 16 characteristic parameters can be calculated with RQA, which are treated as feature representation of protein sequences. Based on such feature representation, the structural class for each protein is predicted with Fisher's linear discriminant algorithm. The jackknife test is used to test and compare our method with other existing methods. The overall accuracies with step-by-step procedure are 65.8% and 64.2% for 1189 and 25PDB data sets, respectively. With one-against-others procedure used widely, we compare our method with five other existing methods. Especially, the overall accuracies of our method are 6.3% and 4.1% higher for the two data sets, respectively. Furthermore, only 16 parameters are used in our method, which is less than that used by other methods. This suggests that the current method may play a complementary role to the existing methods and is promising to perform the prediction of protein structural classes.
Study on peak shape fitting method in radon progeny measurement.
Yang, Jinmin; Zhang, Lei; Abdumomin, Kadir; Tang, Yushi; Guo, Qiuju
2015-11-01
Alpha spectrum measurement is one of the most important methods to measure radon progeny concentration in environment. However, the accuracy of this method is affected by the peak tailing due to the energy losses of alpha particles. This article presents a peak shape fitting method that can overcome the peak tailing problem in most situations. On a typical measured alpha spectrum curve, consecutive peaks overlap even their energies are not close to each other, and it is difficult to calculate the exact count of each peak. The peak shape fitting method uses combination of Gaussian and exponential functions, which can depict features of those peaks, to fit the measured curve. It can provide net counts of each peak explicitly, which was used in the Kerr method of calculation procedure for radon progeny concentration measurement. The results show that the fitting curve fits well with the measured curve, and the influence of the peak tailing is reduced. The method was further validated by the agreement between radon equilibrium equivalent concentration based on this method and the measured values of some commercial radon monitors, such as EQF3220 and WLx. In addition, this method improves the accuracy of individual radon progeny concentration measurement. Especially for the (218)Po peak, after eliminating the peak tailing influence, the calculated result of (218)Po concentration has been reduced by 21 %. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Weaver, Charles L; Schott, Robert J; Prelas, Mark A; Wisniewski, Denis A; Rothenberger, Jason B; Lukosi, Eric D; Oh, Kyuhak
2018-02-01
Radiation damage is a significant concern with both alphavoltaic and betavoltaic cells because their performance degrades, especially with high-energy - (>200keV) beta and alpha particles. Indirect excitation methods, such as the Photon Intermediate Direct Energy Conversion (PIDEC) framework, can protect the transducer from radiation. A nuclear battery using a 90 Sr beta source was constructed by the author's research group, which demonstrated the radiation resistance of a PIDEC cell driven by beta particles (PIDECβ cell). Use of alpha sources to drive nuclear batteries would appear to be much more attractive than beta sources due to higher potential power density. However, they are also subject to higher rates of radiation damage. This paper describes the successful incorporation of alpha particles into the PIDEC framework using the alpha emitter 210 Po to form a PIDECα cell. The PIDECα cell transducer was exposed to alpha particles for over one year without experiencing adverse effects from radiation damage. Copyright © 2017 Elsevier Ltd. All rights reserved.
Effect of humidity on solid-state isomerization of various kinds of lactose during grinding.
Otsuka, M; Ohtani, H; Otsuka, K; Kaneniwa, N
1993-01-01
The effect of humidity on isomerization during grinding of alpha-monohydrate, alpha-anhydrate and beta-anhydrate of lactose was investigated. Samples were ground in an agate centrifugal ball mill at 270 rev min-1 at room temperature (21 degrees C) and at 5 and 60% relative humidity. Crystallinity of the ground lactose was measured by Hermans' method from the powder X-ray diffraction profiles. The alpha- and beta-lactose content of the ground lactose was measured by using angular rotation spectrophotometry. The crystalline lactose samples were transformed into noncrystalline solids by mechanical stress during grinding. After grinding, the adsorbed water content of all ground lactose samples increased, and the isomerized amount increased with increase of the water content during grinding at 5 and 60% relative humidity. The results suggest that the isomerization rate of alpha-monohydrate during grinding may depend on the crystallinity, but those of alpha- and beta-anhydrate depend on the content of adsorbed water.
Data traffic reduction schemes for sparse Cholesky factorizations
NASA Technical Reports Server (NTRS)
Naik, Vijay K.; Patrick, Merrell L.
1988-01-01
Load distribution schemes are presented which minimize the total data traffic in the Cholesky factorization of dense and sparse, symmetric, positive definite matrices on multiprocessor systems with local and shared memory. The total data traffic in factoring an n x n sparse, symmetric, positive definite matrix representing an n-vertex regular 2-D grid graph using n (sup alpha), alpha is equal to or less than 1, processors are shown to be O(n(sup 1 + alpha/2)). It is O(n(sup 3/2)), when n (sup alpha), alpha is equal to or greater than 1, processors are used. Under the conditions of uniform load distribution, these results are shown to be asymptotically optimal. The schemes allow efficient use of up to O(n) processors before the total data traffic reaches the maximum value of O(n(sup 3/2)). The partitioning employed within the scheme, allows a better utilization of the data accessed from shared memory than those of previously published methods.
Bruce, M C; Galinski, M R; Barnwell, J W; Snounou, G; Day, K P
1999-10-01
Allelic diversity at the Plasmodium vivax merozoite surface protein-3alpha (PvMsp-3alpha) locus was investigated using a combined polymerase chain reaction/restriction fragment length polymorphism (PCR/RFLP) protocol. Symptomatic patient isolates from global geographic origins showed a high level of polymorphism at the nucleotide level. These samples were used to validate the sensitivity, specificity, and reproducibility of the PCR/RFLP method. It was then used to investigate PvMsp3alpha diversity in field samples from children living in a single village in a malaria-endemic region of Papua New Guinea, with the aim of assessing the usefulness of this locus as an epidemiologic marker of P. vivax infections. Eleven PvMsp-3alpha alleles were distinguishable in 16 samples with single infections, revealing extensive parasite polymorphism within this restricted area. Multiple infections were easily detected and accounted for 5 (23%) of 22 positive samples. Pairs of samples from individual children provided preliminary evidence for high turnover of P. vivax populations.
Displacement chromatography on cyclodextrin silicas. IV. Separation of the enantiomers of ibuprofen.
Farkas, G; Irgens, L H; Quintero, G; Beeson, M D; al-Saeed, A; Vigh, G
1993-08-13
A displacement chromatographic method has been developed for the preparative separation of the enantiomers of ibuprofen using a beta-cyclodextrin silica stationary phase. The retention behavior of ibuprofen was studied in detail: the log k' vs. polar organic modifier concentration, the log k' vs. pH, the log k' vs. buffer concentration and the log k' vs. 1/T relationships; also, the alpha vs. polar organic modifier concentration, the alpha vs. pH, the alpha vs. buffer concentration and the log alpha vs. 1/T relationships have been determined in order to find the carrier solution composition which results in maximum chiral selectivity and sufficient, but not excessive solute retention (1 < k' < 30). 4-tert.-Butylcyclohexanol, a structurally similar but more retained compound than ibuprofen, was selected as displacer for the separation. Even with an alpha value as small as 1.08, good preparative chiral separations were observed both in the displacement mode and in the overloaded elution mode, up to a sample load of 0.5 mg.
NASA Astrophysics Data System (ADS)
Campbell, John L.; Ganly, Brianna; Heirwegh, Christopher M.; Maxwell, John A.
2018-01-01
Multiple ionization satellites are prominent features in X-ray spectra induced by MeV energy alpha particles. It follows that the accuracy of PIXE analysis using alpha particles can be improved if these features are explicitly incorporated in the peak model description when fitting the spectra with GUPIX or other codes for least-squares fitting PIXE spectra and extracting element concentrations. A method for this incorporation is described and is tested using spectra recorded on Mars by the Curiosity rover's alpha particle X-ray spectrometer. These spectra are induced by both PIXE and X-ray fluorescence, resulting in a spectral energy range from ∼1 to ∼25 keV. This range is valuable in determining the energy-channel calibration, which departs from linearity at low X-ray energies. It makes it possible to separate the effects of the satellites from an instrumental non-linearity component. The quality of least-squares spectrum fits is significantly improved, raising the level of confidence in analytical results from alpha-induced PIXE.
The Effect of Alpha-Lipoic Acid on Mitochondrial Superoxide and Glucocorticoid-Induced Hypertension
Ong, Sharon L. H.; Vohra, Harpreet; Zhang, Yi; Sutton, Matthew; Whitworth, Judith A.
2013-01-01
Aims. To examine the effect of alpha-lipoic acid, an antioxidant with mitochondrial superoxide inhibitory properties, on adrenocorticotrophic hormone- (ACTH-HT) and dexamethasone-induced hypertensions (DEX-HT) in rats and if any antihypertensive effect is mediated via mitochondrial superoxide inhibition. Methods. In a prevention study, rats received ground food or alpha-lipoic-acid-laced food (10 mg/rat/day) for 15 nights. Saline, adrenocorticotrophic hormone (ACTH, 0.2 mg/kg/day), or dexamethasone (DEX, 10 μg/rat/day) was injected subcutaneously from day 5 to day 11. In a reversal study, rats received alpha-lipoic-acid-laced food 4 days after commencement of saline or DEX. Tail-cuff systolic blood pressure (SBP) was measured second daily. Kidney mitochondrial superoxide was examined using (MitoSOX) Red (MitoSOX) via flow cytometry. Results. SBP was increased by ACTH (P < 0.0005) and DEX (P < 0.0005). Alpha-lipoic acid alone did not alter SBP. With alpha-lipoic acid pretreatment, SBP was increased by ACTH (P′ < 0.005) but not by DEX. Alpha-lipoic partially prevented ACTH-HT (P′ < 0.0005) and fully prevented DEX-HT (P′ < 0.0005) but failed to reverse DEX-HT. ACTH and DEX did not increase MitoSOX signal. In ACTH-hypertensive rats, high-dose alpha-lipoic acid (100 mg/rat/day) did not decrease SBP further but raised MitoSOX signal (P < 0.001), suggesting prooxidant activity. Conclusion. Glucocorticoid-induced hypertension in rats is prevented by alpha-lipoic acid via mechanisms other than mitochondrial superoxide reduction. PMID:23533693
NASA Astrophysics Data System (ADS)
Garcia, Timothy Richard
Pyroprocessing is a method of using high-temperature molten salts and electric fields to separate and collect fuel isotopes of used nuclear fuel. It has been has been tested in the U.S. at Idaho National Laboratory as a key step in closing the nuclear fuel cycle. One technical problem with the pyroprocessing method is a lack of knowledge regarding the actinide concentrations in the salt bath during operation, since on-line techniques for measuring these concentrations are not presently available. 4H-SiC Schottky diode detectors can potentially fulfill this need. Such detectors would operate in contact with the molten salt, and measure concentrations via alpha-particle spectroscopy. This work seeks to fabricate and characterize 4H-SiC Schottky diode detectors at high temperature, model the alpha particle spectrum expected in a molten salt, and model the operation of the detectors to confirm the physics of operation is as expected. In this work, 4H-SiC Schottky diode detectors were fabricated at OSU Nanotech West. After fabrication, these detectors were characterized using both I-V curves and Am-241 alpha-particle energy spectra. All measurements were made as a function of temperature, from room temperature up to 500°C. The average energy required to create an electron-hole pair was observed to decrease with an increase of temperature, due to a decrease of both the 4H-SiC bandgap and non-linear energy loss terms. Furthermore, the FWHM of the spectra was observed to be dependent on the leakage current at a certain temperature, and not dependent on the temperature itself. Secondly, the alpha particle energy spectrum in the pyroprocessing environment was modeled using SRIM. The molten salt was modeled in 3 different geometries, with or without a protective cover material on top of the detector. Due to the loss of alpha-particle energy in the molten salt itself, a high-energy alpha emitter may completely cover the spectrum from a lower-energy alpha emitter. Each of the geometries simulated showed a different sensitivity to the lower-energy alpha emitter. Regardless of which geometry was modeled, it was observed that it is possible to measure both the emission energy of the alpha particles, as well as the concentration of the alpha emitter in the liquid. Lastly, Sentaurus TCAD was used to simulate the detection of alpha-particle charge collection in situations that are relevant to the molten salt alpha particle energy spectra. The effect of electric field negation was investigated, as well as velocity saturation. Finally, the dependence of charge recombination on temperature, alpha particle energy, and angle of incidence was investigated. These simulations captured the measurements performed at room temperature. With changed angle of incidence, the change in the amount of charge collected was less than 1 percent, indicating a weak dependence. Also, the amount of charge lost to Auger recombination was seen to increase with temperature. This disagrees with observations from experiment, indicating that the temperature dependence of one or more parameters of the model may not be accurate.
Metal catalyzed synthesis of hyperbranched ethylene and/or .alpha.-olefin polymers
Sen, Ayusman; Kim, Jang Sub; Pawlow, James H.; Murtuza, Shahid; Kacker, Smita; Wojcinski, III, Louis M.
2001-01-01
Oily hyperbranched polymers derived from ethylene, propylene, butene and/or a C.sub.5 -C.sub.24 .alpha.-olefin, and a method for their synthesis, are disclosed. The polymers have non-regular microstructures and are characterized by a ratio ({character pullout})of methyl hydrogens centered around 0.85 ppm on the 1H-NMR spectra of the polymers relative to total aliphatic hydrogens of from about 0.40 to about 0.65 for polymers derived from ethylene or butene, and a ratio ({character pullout})of from greater than 0.50 to about 0.65 for polymers derived from propylene. A method for grafting hyperbranched polymers derived from ethylene, propylene, butene and/or a C.sub.5 -C.sub.24 .alpha.-olefin onto aromatic rings in organic molecules and polymers, and the resulting grafted materials, are also disclosed. The hyperbranched polymers and grafted materials are useful, for example, as lubricants and lubricant additives.
Partial Accretion in the Propeller Stage of Low-mass X-Ray Binary Aql X-1
NASA Astrophysics Data System (ADS)
Güngör, C.; Ekşi, K. Y.; Göğüş, E.; Güver, T.
2017-10-01
Aql X-1 is one of the most prolific low-mass X-ray binary transients (LMXBTs) showing outbursts almost annually. We present the results of our spectral analyses of Rossi X-Ray Timing Explorer/proportional counter-array observations of the 2000 and 2011 outbursts. We investigate the spectral changes related to the changing disk-magnetosphere interaction modes of Aql X-1. The X-ray light curves of the outbursts of LMXBTs typically show phases of fast rise and exponential decay. The decay phase shows a “knee” where the flux goes from the slow-decay to the rapid-decay stage. We assume that the rapid decay corresponds to a weak propeller stage at which a fraction of the inflowing matter in the disk accretes onto the star. We introduce a novel method for inferring, from the light curve, the fraction of the inflowing matter in the disk that accretes onto the neutron star depending on the fastness parameter. We determine the fastness parameter range within which the transition from the accretion to the partial propeller stage is realized. This fastness parameter range is a measure of the scale height of the disk in units of the inner disk radius. We applied the method to a sample of outbursts of Aql X-1 with different maximum flux and duration times. We show that different outbursts with different maximum luminosity and duration follow a similar path in the parameter space of accreted/inflowing mass flux fraction versus fastness parameter.
AN EMPIRICAL METHOD FOR IMPROVING THE QUALITY OF RXTE HEXTE SPECTRA
DOE Office of Scientific and Technical Information (OSTI.GOV)
Garcia, Javier A.; Steiner, James F.; McClintock, Jeffrey E.
2016-03-01
We have developed a correction tool to improve the quality of Rossi X-ray Timing Explorer (RXTE) High Energy X-ray Timing Experiment (HEXTE) spectra by employing the same method we used earlier to improve the quality of RXTE Proportional Counter Array (PCA) spectra. We fit all of the hundreds of HEXTE spectra of the Crab individually to a simple power-law model, some 37 million counts in total for Cluster A and 39 million counts for Cluster B, and we create for each cluster a combined spectrum of residuals. We find that the residual spectrum of Cluster A is free of instrumental artifacts while that of Clustermore » B contains significant features with amplitudes ∼1%; the most prominent is in the energy range 30–50 keV, which coincides with the iodine K edge. Starting with the residual spectrum for Cluster B, via an iterative procedure we created the calibration tool hexBcorr for correcting any Cluster B spectrum of interest. We demonstrate the efficacy of the tool by applying it to Cluster B spectra of two bright black holes, which contain several million counts apiece. For these spectra, application of the tool significantly improves the goodness of fit, while affecting only slightly the broadband fit parameters. The tool may be important for the study of spectral features, such as cyclotron lines, a topic that is beyond the scope of this paper.« less
Falliner, A; Hahne, H J; Hedderich, J; Brossmann, J; Hassenpflug, J
2004-04-01
To define which sonographic section planes relative to the acetabular inlet plane will produce analyzable images with the methods of Graf and Terjesen. Anatomical specimens of infant hip joints were investigated in a water bath using the methods of Graf and Terjesen. Acetabular position was varied in defined increments with respect to the ultrasound beam. The alpha angles and the femoral head coverage (FHC) were measured. To obtain images analyzable by the two methods, the ultrasound beam had to intersect with the acetabular inlet plane at defined angles. The acetabular notch had to be anteriorly rotated from the ultrasound beam plane by at least 20 degrees. Beam entry within a 50 degrees sector posterior to the perpendicular on the inlet plane resulted in analyzable images. The stepwise multiple linear regression analysis showed that alpha angles and FHC were much affected by the coronal-plane transducer tilt. The fact that caudal tilts of the transducer are associated with reduced alpha angles and FHC values should be kept in mind in clinical ultrasound investigations. It is recommended that the transducer should be put on the greater trochanter perpendicular to the transverse axis of the body.
Ultra-performance liquid chromatographic determination of tocopherols and retinol in human plasma.
Bell, Edward C; John, Mathew; Hughes, Rodney J; Pham, Thu
2014-10-01
A rapid, selective and sensitive ultra-performance liquid chromatography method has been developed for the detection and quantification of tocopherols and retinol in human plasma. Alpha-tocopherol, gamma-tocopherol and retinol are assayed using fluorescence detection. Excitation/emission wavelengths are 295/330 nm and 325/470 nm for the analysis of both tocopherols and retinol, respectively. Retinol acetate is employed as the internal standard. The reversed-phase method incorporates gradient elution with a mobile phase consisting of methanol and acetonitrile. Separation of vitamin compounds is achieved using a bridged ethyl hybrid C18 column. The retention times for retinol, retinol acetate, gamma-tocopherol and alpha-tocopherol are 1.6, 1.8, 3.9 and 4.3 min, respectively. The limits of quantification for retinol, gamma-tocopherol and alpha-tocopherol were 0.02, 0.02 and 0.1 µg/mL, respectively. The assay method is suitable for the analysis of tocopherols and retinol in human plasma. The method may be applied following the ingestion of foods fortified with these fat-soluble vitamins. © The Author [2013]. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Optimisation of nasal swab analysis by liquid scintillation counting.
Dai, Xiongxin; Liblong, Aaron; Kramer-Tremblay, Sheila; Priest, Nicholas; Li, Chunsheng
2012-06-01
When responding to an emergency radiological incident, rapid methods are needed to provide the physicians and radiation protection personnel with an early estimation of possible internal dose resulting from the inhalation of radionuclides. This information is needed so that appropriate medical treatment and radiological protection control procedures can be implemented. Nasal swab analysis, which employs swabs swiped inside a nostril followed by liquid scintillation counting of alpha and beta activity on the swab, could provide valuable information to quickly identify contamination of the affected population. In this study, various parameters (such as alpha/beta discrimination, swab materials, counting time and volume of scintillation cocktail etc) were evaluated in order to optimise the effectiveness of the nasal swab analysis method. An improved nasal swab procedure was developed by replacing cotton swabs with polyurethane-tipped swabs. Liquid scintillation counting was performed using a Hidex 300SL counter with alpha/beta pulse shape discrimination capability. Results show that the new method is more reliable than existing methods using cotton swabs and effectively meets the analysis requirements for screening personnel in an emergency situation. This swab analysis procedure is also applicable to wipe tests of surface contamination to minimise the source self-absorption effect on liquid scintillation counting.
NASA Astrophysics Data System (ADS)
Ali, Nouruddin W.; Abdelwahab, Nada S.; Abdelkawy, M.; Emam, Aml A.
2016-02-01
A pharmaceutically marketed mixture of Yohimbine, Alpha-tocopheryl acetate, Niacin, and Caffeine co-formulated as a promising therapy for erectile dysfunction. Simultaneous determination of the aforementioned pharmaceutical formulation without prior separation steps was applied using mean centering of ratio spectra and triple divisor spectrophotometric methods. Mean centering of ratio spectra method depended on using the mean centered ratio spectra in three successive steps which eliminated the derivative steps and so the signal to noise ratio was improved. The absorption spectra of the prepared solutions were measured in the wavelength range of 215-300 nm in the concentration ranges of 1-15, 3-15, 1-20, and 3-15 μg mL- 1 for Yohimbine, Alpha-tocopheryl acetate, Niacin, and Caffeine, respectively. The amplitudes of the mean centered third ratio spectra were measured at 250 nm and 268 nm for Yohimbine and Alpha-tocopheryl acetate, respectively and at peak to peak 272-273 and 262-263 nm for Niacin and Caffeine, respectively. In triple divisor method each drug in the quaternary mixture was determined by dividing the spectrum of the quaternary mixture by a standard spectrum of a mixture containing equal concentrations of the other three drugs. First derivative of these ratio spectra was obtained where determination could be achieved without any interference from the other three drugs. Amplitudes of 1-15, 3-15, 1-15, and 3-15 μg mL- 1 were used for selective determination of Yohimbine, Alpha-tocopheryl acetate, Niacin, and Caffeine, respectively. Laboratory prepared mixtures were analyzed by the developed novel methods to investigate their selectivity also, Super Act® capsules were successfully analyzed to ensure absence of interference from additives. The developed methods were validated according to the ICH guidelines. The proposed methods were statistically compared with each other and with the reported methods; using student t-test, F-test, and one way ANOVA, where no significant difference was found with respect to accuracy and precision.
Ashley, Ryan L; Arreguin-Arevalo, J Alejandro; Nett, Terry M
2009-01-01
Background Classically, progesterone has been thought to act only through the well-known genomic pathway involving hormone binding to nuclear receptors and subsequent modulation of gene expression. However, there is increasing evidence for rapid, non-genomic effects of progesterone in a variety of mammalian tissues and it is possible that a membrane PR (mPR) is causing these events. We recently isolated and characterized an ovine mPR referred to as mPR-alpha, distinct from the nuclear PR. Based on predicted structural analysis, the ovine mPR-alpha possesses seven transmembrane domains typical of G protein-coupled receptors. Despite the homology to other reported mPRs, information pertaining to the steroid binding characteristics of the ovine mPR-alpha was lacking. Additionally, the ovine mPR-alpha transcript has been identified in the hypothalamus, pituitary, uterus, ovary and corpus luteum, yet changes in expression of the ovine mPR-alpha in these tissues were not known. Consequently, the purpose of this work was to determine the steroid binding characteristics of the ovine mPR-alpha and to investigate possible changes in expression of the ovine mPR-alpha in reproductive tissues throughout the estrous cycle. Methods Binding studies were performed using crude membrane fractions from CHO cells expressing the mPR-alpha. Using quantitative Real-time PCR we determined the expression pattern of mRNA for the ovine mPR-alpha during the ovine estrous cycle in tissues known to express the mPR-alpha. Jugular blood samples were also collected and analyzed for serum concentrations of P4 to ensure ewes were at the appropriate stage of their cycle. Results Only progesterone, 20alpha-hydroxyprogesterone and 17alpha-hydroxyprogesterone were able to displace binding of 3H-P4 (P < 0.001) to membrane fractions from CHO cells expressing ovine mPR-alpha. The average B-max and Kd values for three separate experiments were 624 +/- 119 fmol/micro gram protein and 122 +/- 50 nM, respectively. Significant changes in expression of mRNA for the mPR-alpha during the estrous cycle were noted in the corpus luteum and uterus. Conclusion The mPR-alpha specifically binds progestins and its expression was correlated to progesterone secretion during the ovine estrous cycle. Results from the present studies suggest that mPR-alpha may have an important physiological role during the ovine estrous cycle. PMID:19432978
Al Darwish, R; Staudacher, A H; Li, Y; Brown, M P; Bezak, E
2016-11-01
In targeted radionuclide therapy, regional tumors are targeted with radionuclides delivering therapeutic radiation doses. Targeted alpha therapy (TAT) is of particular interest due to its ability to deliver alpha particles of high linear energy transfer within the confines of the tumor. However, there is a lack of data related to alpha particle distribution in TAT. These data are required to more accurately estimate the absorbed dose on a cellular level. As a result, there is a need for a dosimeter that can estimate, or better yet determine the absorbed dose deposited by alpha particles in cells. In this study, as an initial step, the authors present a transmission dosimetry design for alpha particles using A549 lung carcinoma cells, an external alpha particle emitting source (radium 223; Ra-223) and a Timepix pixelated semiconductor detector. The dose delivery to the A549 lung carcinoma cell line from a Ra-223 source, considered to be an attractive radionuclide for alpha therapy, was investigated in the current work. A549 cells were either unirradiated (control) or irradiated for 12, 1, 2, or 3 h with alpha particles emitted from a Ra-223 source positioned below a monolayer of A549 cells. The Timepix detector was used to determine the number of transmitted alpha particles passing through the A549 cells and DNA double strand breaks (DSBs) in the form of γ-H2AX foci were examined by fluorescence microscopy. The number of transmitted alpha particles was correlated with the observed DNA DSBs and the delivered radiation dose was estimated. Additionally, the dose deposited was calculated using Monte Carlo code SRIM. Approximately 20% of alpha particles were transmitted and detected by Timepix. The frequency and number of γ-H2AX foci increased significantly following alpha particle irradiation as compared to unirradiated controls. The equivalent dose delivered to A549 cells was estimated to be approximately 0.66, 1.32, 2.53, and 3.96 Gy after 12, 1, 2, and 3 h irradiation, respectively, considering a relative biological effectiveness of alpha particles of 5.5. The study confirmed that the Timepix detector can be used for transmission alpha particle dosimetry. If cross-calibrated using biological dosimetry, this method will give a good indication of the biological effects of alpha particles without the need for repeated biological dosimetry which is costly, time consuming, and not readily available.
ERIC Educational Resources Information Center
Dwyer, Tammy J.; Fillo, Jeremiah D.
2006-01-01
The analytical system to teach the subtleties of assaying alpha-dicarbonyl compounds in wine is described. Spectrophotometry is determined to be minimally useful in the experiment where the GC-MS (methyglyoxal) method proved to be ideal to confirm that the compounds analyzed in the wine samples were indeed the glyoxals based on the formation of…
Hashimoto, Tetsuo; Sanada, Yukihisa; Uezu, Yasuhiro
2004-05-01
A delayed coincidence method, time-interval analysis (TIA), has been applied to successive alpha- alpha decay events on the millisecond time-scale. Such decay events are part of the (220)Rn-->(216)Po ( T(1/2) 145 ms) (Th-series) and (219)Rn-->(215)Po ( T(1/2) 1.78 ms) (Ac-series). By using TIA in addition to measurement of (226)Ra (U-series) from alpha-spectrometry by liquid scintillation counting (LSC), two natural decay series could be identified and separated. The TIA detection efficiency was improved by using the pulse-shape discrimination technique (PSD) to reject beta-pulses, by solvent extraction of Ra combined with simple chemical separation, and by purging the scintillation solution with dry N(2) gas. The U- and Th-series together with the Ac-series were determined, respectively, from alpha spectra and TIA carried out immediately after Ra-extraction. Using the (221)Fr-->(217)At ( T(1/2) 32.3 ms) decay process as a tracer, overall yields were estimated from application of TIA to the (225)Ra (Np-decay series) at the time of maximum growth. The present method has proven useful for simultaneous determination of three radioactive decay series in environmental samples.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Khodam-Mohammadi, A.; Monshizadeh, M.
We give a review of the existence of Taub-NUT/bolt solutions in Einstein Gauss-Bonnet gravity with the parameter {alpha} in six dimensions. Although the spacetime with base space S{sup 2}xS{sup 2} has a curvature singularity at r=N, which does not admit NUT solutions, we may proceed with the same computations as in the CP{sup 2} case. The investigation of thermodynamics of NUT/bolt solutions in six dimensions is carried out. We compute the finite action, mass, entropy, and temperature of the black hole. Then the validity of the first law of thermodynamics is demonstrated. It is shown that in NUT solutions allmore » thermodynamic quantities for both base spaces are related to each other by substituting {alpha}{sup CP{sup k}}=[(k+1)/k]{alpha}{sup S{sup 2}}{sup xS{sup 2}}{sup x...S{sub k}{sup 2}}. So, no further information is given by investigating NUT solutions in the S{sup 2}xS{sup 2} case. This relation is not true for bolt solutions. A generalization of the thermodynamics of black holes to arbitrary even dimensions is made using a new method based on the Gibbs-Duhem relation and Gibbs free energy for NUT solutions. According to this method, the finite action in Einstein Gauss-Bonnet is obtained by considering the generalized finite action in Einstein gravity with an additional term as a function of {alpha}. Stability analysis is done by investigating the heat capacity and entropy in the allowed range of {alpha}, {lambda}, and N. For NUT solutions in d dimensions, there exists a stable phase at a narrow range of {alpha}. In six-dimensional bolt solutions, the metric is completely stable for B=S{sup 2}xS{sup 2} and is completely unstable for the B=CP{sup 2} case.« less