182 results on '"Weber WJ"'
Search Results
2. Electronic excitation induced amorphization in titanate pyrochlores: An ab initio molecular dynamics study
- Author
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Xiao, HY, Weber, WJ, Zhang, Y, Zu, XT, Li, S, Xiao, HY, Weber, WJ, Zhang, Y, Zu, XT, and Li, S
- Abstract
The response of titanate pyrochlores (A2Ti2O7, A = Y, Gd and Sm) to electronic excitation is investigated utilizing an ab initio molecular dynamics method. All the titanate pyrochlores are found to undergo a crystalline-to-amorphous structural transition under a low concentration of electronic excitations. The transition temperature at which structural amorphization starts to occur depends on the concentration of electronic excitations. During the structural transition, O2-like molecules are formed, and this anion disorder further drives cation disorder that leads to an amorphous state. This study provides new insights into the mechanisms of amorphization in titanate pyrochlores under laser, electron and ion irradiations.
- Published
- 2015
3. LISA Pathfinder: mission and status
- Author
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Antonucci, F, Armano, M, Audley, H, Auger, G, Benedetti, M, Binetruy, P, Boatella, C, Bogenstahl, J, Bortoluzzi, D, Bosetti, P, Caleno, M, Cavalleri, A, Cesa, M, Chmeissani, M, Ciani, G, Conchillo, A, Congedo, G, Cristofolini, I, Cruise, M, Danzmann, K, De Marchi, F, Diaz-Aguilo, M, Diepholz, I, Dixon, G, Dolesi, R, Dunbar, N, Fauste, J, Ferraioli, L, Fertin, D, Fichter, W, Fitzsimons, E, Freschi, M, Marin, AG, Marirrodriga, CG, Gerndt, R, Gesa, L, Gilbert, F, Giardini, D, Grimani, C, Grynagier, A, Guillaume, B, Guzmán, F, Harrison, I, Heinzel, G, Hewitson, M, Hollington, D, Hough, J, Hoyland, D, Hueller, M, Huesler, J, Jeannin, O, Jennrich, O, Jetzer, P, Johlander, B, Killow, C, Llamas, X, Lloro, I, Lobo, A, Maarschalkerweerd, R, Madden, S, Mance, D, Mateos, I, McNamara, PW, Mendes, J, Mitchell, E, Monsky, A, Nicolini, D, Nicolodi, D, Nofrarias, M, Pedersen, F, Perreur-Lloyd, M, Perreca, A, Plagnol, E, Prat, P, Racca, GD, Rais, B, Ramos-Castro, J, Reiche, J, Perez, JAR, Robertson, D, Rozemeijer, H, Sanjuan, J, Schleicher, A, Schulte, M, Shaul, D, Stagnaro, L, Strandmoe, S, Steier, F, Sumner, TJ, Taylor, A, Texier, D, Trenkel, C, Tombolato, D, Vitale, S, Wanner, G, Ward, H, Waschke, S, Wass, P, Weber, WJ, Zweifel, P, Gruppo Collegato di Trento, National Institute for Nuclear Physics ( INFN ), European Space Astronomy Centre, European Space Agency ( ESA ), Max-Planck-Institut für Gravitationsphysik, Universitat Hannover, AstroParticule et Cosmologie ( APC - UMR 7164 ), Centre National de la Recherche Scientifique ( CNRS ) -Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Observatoire de Paris-Université Paris Diderot - Paris 7 ( UPD7 ) -Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ), Centre National d'Etudes Spatiales ( CNES ), European Space Technology Centre, IFAE, Universitat Autònoma de Barcelona [Barcelona] ( UAB ), Department of Physics [Gainesville], University of Florida [Gainesville], ICE, Institut d'Estudis Espacials de Catalunya ( IEEC-CSIC ), School of Physics and Astronomy [Birmingham], University of Birmingham [Birmingham], EPSC, Astrium Ltd, Institut für Flugmechanik und Flugregelung, Department of Physics and Astronomy, University of Glasgow, Astrium GmbH, Institut für Geophysik [Zürich], Eidgenössische Technische Hochschule [Zürich] ( ETH Zürich ), Istituto di Fisica, NASA Goddard Space Flight Center ( GSFC ), European Space Operations Centre, Blackett Laboratory, Imperial College London, Institut für Theoretische Physik, Universität Zürich [Zürich] ( UZH ), NTE-SENER, Departament d'Enginyeria Electrònica [Barcelona], Istituto Nazionale di Fisica Nucleare (INFN), European Space Astronomy Centre (ESAC), Agence Spatiale Européenne = European Space Agency (ESA), Max-Planck-Institut für Gravitationsphysik ( Albert-Einstein-Institut ) (AEI), Max-Planck-Gesellschaft, AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Centre National d'Études Spatiales [Toulouse] (CNES), European Space Research and Technology Centre (ESTEC), Institut de Física d’Altes Energies [Barcelone] (IFAE), Universitat Autònoma de Barcelona (UAB), Department of Physics [Gainesville] (UF|Physics), University of Florida [Gainesville] (UF), Institut d'Estudis Espacials de Catalunya (IEEC-CSIC), SUPA School of Physics and Astronomy [Glasgow], Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), NASA Goddard Space Flight Center (GSFC), Universität Zürich [Zürich] = University of Zurich (UZH), National Institute for Nuclear Physics (INFN), European Space Agency (ESA), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), Universitat Autònoma de Barcelona [Barcelona] (UAB), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), Universität Zürich [Zürich] (UZH), Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)
- Subjects
Physics and Astronomy (miscellaneous) ,Physical Sciences ,[PHYS.GRQC]Physics [physics]/General Relativity and Quantum Cosmology [gr-qc] ,ComputingMilieux_MISCELLANEOUS ,[ PHYS.GRQC ] Physics [physics]/General Relativity and Quantum Cosmology [gr-qc] - Abstract
LISA Pathfinder, the second of the European Space Agency's Small Missions for Advanced Research in Technology (SMART), is a dedicated technology demonstrator for the joint ESA/NASA Laser Interferometer Space Antenna (LISA) mission. The technologies required for LISA are many and extremely challenging. This coupled with the fact that some flight hardware cannot be fully tested on ground due to Earth-induced noise led to the implementation of the LISA Pathfinder mission to test the critical LISA technologies in a flight environment. LISA Pathfinder essentially mimics one arm of the LISA constellation by shrinking the 5 million kilometre armlength down to a few tens of centimetres, giving up the sensitivity to gravitational waves, but keeping the measurement technology: the distance between the two test masses is measured using a laser interferometric technique similar to one aspect of the LISA interferometry system. The scientific objective of the LISA Pathfinder mission consists then of the first in-flight test of low frequency gravitational wave detection metrology. LISA Pathfinder is due to be launched in 2013 on-board a dedicated small launch vehicle (VEGA). After a series of apogee raising manoeuvres using an expendable propulsion module, LISA Pathfinder will enter a transfer orbit towards the first Sun-Earth Lagrange point (L1). After separation from the propulsion module, the LPF spacecraft will be stabilized using the micro-Newton thrusters, entering a 500 000 km by 800 000 km Lissajous orbit around L1. Science results will be available approximately 2 months after launch. © 2011 IOP Publishing Ltd.
- Published
- 2011
4. Upper limits to surface-force disturbances on LISA proof masses and the possibility of observing galactic binaries
- Author
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Carbone L (Carbone, Ludovico), Ciani G (Ciani, Giacomo), Dolesi R (Dolesi, Rita), Hueller M (Hueller, Mauro), Tombolato D (Tombolato, David), Vitale S (Vitale, Stefano), Weber WJ (Weber, William Joseph), Cavalleri A (Cavalleri, and Antonella)
- Published
- 2007
5. Thermal gradient-induced forces on geodesic reference masses for LISA
- Author
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Carbone L (Carbone, L.), Cavalleri A (Cavalleri, A.), Ciani G (Ciani, G.), Dolesi R (Dolesi, R.), Hueller M (Hueller, M.), Tombolato D (Tombolato, D.), Vitale S (Vitale, S.), Weber WJ (Weber, and W. J.)
- Published
- 2007
6. Molecular Dynamics Modeling of the Evolution of SiC Thermal Conductivity with Accumulation of Irradiation Damage
- Author
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Crocombette, Jp., Dumazer, G., Nguyen, Qh., Weber, Wj., Gao, F., CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and CEA-Direction de l'Energie Nucléaire (CEA-DEN)
- Subjects
[PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th] ,[PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex] - Abstract
International audience; SiC thermal conductivity is known to decrease under irradiation. To numerically model this effect, we studied the variation of the thermal conductivity of cubic SiC with the defect accumulation induced by displacement cascades. We use empirical potential of the Tersoff type in the framework of non-equilibrium molecular dynamics. The conductivity is found to decrease with dose in very good quantitative agreement with low temperature irradiation experiments. The results are analyzed in view of the amorphization states that are created by the cascade accumulation simulations. The decrease of the conductivity observed at lower doses is related to the creation of point defects. The calculated values are close to the smallest measured values after high temperature irradiation. A subsequent decrease takes place upon further cascade accumulation. It is characteristic of the amorphization of the material and is experimentally observed for low temperature irradiation only.
- Published
- 2007
7. Effects of Calcium and Sediment Concentrations on the Release of Metals and Nutrients from Dredge Spoil Dispersions
- Author
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Snitz, FL, primary, Weber, WJ, additional, Barney, JL, additional, and Posner, JC, additional
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8. Quantitative morphology of aluminum silicate nanoaggregates
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Wang, CM, Thevuthasan, S, Shutthanandan, V, Cavanagh, A, Walton, J, Jiang, W, Weber, WJ, Thomas, LE, Jian, J, Crosta, GF, Piqueras, J, Zypman, FR, Bonnell, DA, Shreve, AP, Crosta, G, Sung, C, Kang, B, Ospina, C, Stenhouse, P, Wang, CM, Thevuthasan, S, Shutthanandan, V, Cavanagh, A, Walton, J, Jiang, W, Weber, WJ, Thomas, LE, Jian, J, Crosta, GF, Piqueras, J, Zypman, FR, Bonnell, DA, Shreve, AP, Crosta, G, Sung, C, Kang, B, Ospina, C, and Stenhouse, P
- Abstract
Aluminum silicate nanoaggregates grown on organic multilayer templates were imaged by a transmission electron microscope. Images were processed by fractal and FOURIER analysis. The estimated mass fractal dimension suggested that aggregate formation was diffusion limited. Nonlinear filtering of FOURIER spectra, which included comparison with a model spectral density, yielded «enhanced power spectra». Some morphological descriptors were extracted from the latter. The main result, materials classification, was attained by a two-scale procedure. Some descriptors were related to the material properties such as nanoparticle size distribution and sharpness of aggregate boundaries
- Published
- 2003
9. Local Area Volume Change in Ion-Irradiated SiC Measured by Electron Energy Loss Spectroscopy
- Author
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Bae, I-T, primary, Zhang, Y, additional, and Weber, WJ, additional
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- 2010
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10. Strain- and Defect-Enhanced Cavity Formation and Au Precipitation at the Interfaces of a ZrO2/SiO2/Si Heterostructure
- Author
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Edmondson, P, primary, Wang, C, additional, Zhu, Z, additional, Namavar, F, additional, Weber, WJ, additional, and Zhang, Y, additional
- Published
- 2010
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11. Effect of selective coronary arteriography on myocardial blood flow in the intact dog
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Carson Rp, Wilson Ws, and Weber Wj
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medicine.medical_specialty ,Radioisotope Dilution Technique ,Time Factors ,Xenon ,Diatrizoate ,Blood Pressure ,Precordial examination ,Dogs ,Heart Rate ,Internal medicine ,medicine ,Animals ,Cardiac Output ,business.industry ,Angiocardiography ,General Medicine ,Coronary arteriography ,Blood flow ,Coronary Vessels ,Radiopaque agent ,medicine.anatomical_structure ,Regional Blood Flow ,Cardiology ,business ,Artery ,medicine.drug - Abstract
Changes in myocardial blood flow as measured with the Nenon-133 precordial clearance method were studied following selective coronary artery injection of Na-methylglucamine diatrizoate (Hypaque-M 75%). Measurements started 15 to 25 seconds after injection of the radiopaque agent showed a sub
- Published
- 1969
12. Solubilization rates of n-alkanes in micellar solutions of nonionic surfactants
- Author
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Prak, Djl, Abriola, Lm, Weber, Wj, Bocskay, Ka, and Kurt Pennell
13. SURFACTANT ENHANCED SOLUBILIZATION OF ENTRAPPED DODECANE IN SOIL COLUMNS
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Kurt Pennell, Abriola, Lm, Dekker, Tj, and Weber, Wj
14. Quantitative morphology of aluminum silicate nanoaggregates
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Crosta, G, Sung, C, Kang, B, Ospina, C, Stenhouse, P, Wang, CM, Thevuthasan, S, Shutthanandan, V, Cavanagh, A, Walton, J, Jiang, W, Weber, WJ, Thomas, LE, Jian, J, Crosta, GF, Piqueras, J, Zypman, FR, Bonnell, DA, Shreve, AP, Crosta, G, Sung, C, Kang, B, Ospina, C, and Stenhouse, P
- Subjects
classification ,CHIM/01 - CHIMICA ANALITICA ,SECS-S/02 - STATISTICA PER LA RICERCA SPERIMENTALE E TECNOLOGICA ,Electronic, Optical and Magnetic Material ,biomimetic growth ,Fourier analysi ,morphological descriptors ,INF/01 - INFORMATICA ,fractal geometry ,FIS/03 - FISICA DELLA MATERIA - Abstract
Aluminum silicate nanoaggregates grown on organic multilayer templates were imaged by a transmission electron microscope. Images were processed by fractal and FOURIER analysis. The estimated mass fractal dimension suggested that aggregate formation was diffusion limited. Nonlinear filtering of FOURIER spectra, which included comparison with a model spectral density, yielded «enhanced power spectra». Some morphological descriptors were extracted from the latter. The main result, materials classification, was attained by a two-scale procedure. Some descriptors were related to the material properties such as nanoparticle size distribution and sharpness of aggregate boundaries
- Published
- 2003
15. Nanoscale core-shell structure and recrystallization of swift heavy ion tracks in SrTiO 3 .
- Author
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Gupta AK, Zarkadoula E, Ziatdinov M, Kalinin SV, Paduri VR, Hachtel JA, Zhang Y, Trautmann C, Weber WJ, and Sachan R
- Abstract
It is widely accepted that the interaction of swift heavy ions with many complex oxides is predominantly governed by the electronic energy loss that gives rise to nanoscale amorphous ion tracks along the penetration direction. The question of how electronic excitation and electron-phonon coupling affect the atomic system through defect production, recrystallization, and strain effects has not yet been fully clarified. To advance the knowledge of the atomic structure of ion tracks, we irradiated single crystalline SrTiO
3 with 629 MeV Xe ions and performed comprehensive electron microscopy investigations complemented by molecular dynamics simulations. This study shows discontinuous ion-track formation along the ion penetration path, comprising an amorphous core and a surrounding few monolayer thick shell of strained/defective crystalline SrTiO3 . Using machine-learning-aided analysis of atomic-scale images, we demonstrate the presence of 4-8% strain in the disordered region interfacing with the amorphous core in the initially formed ion tracks. Under constant exposure of the electron beam during imaging, the amorphous part of the ion tracks readily recrystallizes radially inwards from the crystalline-amorphous interface under the constant electron-beam irradiation during the imaging. Cation strain in the amorphous region is observed to be significantly recovered, while the oxygen sublattice remains strained even under the electron irradiation due to the present oxygen vacancies. The molecular dynamics simulations support this observation and suggest that local transient heating and annealing facilitate recrystallization process of the amorphous phase and drive Sr and Ti sublattices to rearrange. In contrast, the annealing of O atoms is difficult, thus leaving a remnant of oxygen vacancies and strain even after recrystallization. This work provides insights for creating and transforming novel interfaces and nanostructures for future functional applications.- Published
- 2024
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16. The Evolution of Science and Regulation of Dietary Supplements: Past, Present, and Future.
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Coates PM, Bailey RL, Blumberg JB, El-Sohemy A, Floyd E, Goldenberg JZ, Gould Shunney A, Holscher HD, Nkrumah-Elie Y, Rai D, Ritz BW, and Weber WJ
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- Humans, Artificial Intelligence, Nutrigenomics, United States, Dietary Supplements history, Dietary Supplements standards
- Abstract
Dietary supplement use in the United States is widespread and increasing, especially among certain population groups, such as older Americans. The science surrounding dietary supplements has evolved substantially over the last few decades since their formal regulation in 1994. Much has been learned about the mechanisms of action of many dietary supplement ingredients, but the evidence on their health effects is still building. As is true of much nutrition research, there are many studies that point to health effects, but not all are at the level of scientific evidence (e.g., randomized controlled interventions), rigor, or quality needed for definitive statements of efficacy regarding clinical end points. New technologies and approaches are being applied to the science of dietary supplements, including nutrigenomics and microbiome analysis, data science, artificial intelligence (AI), and machine learning-all of which can elevate the science behind dietary supplements. Products can contain an array of bioactive compounds derived from foods as well as from medicinal plants, which creates enormous challenges in data collection and management. Clinical applications, particularly those aimed at providing personalized nutrition options for patients, have become more sophisticated as dietary supplements are incorporated increasingly into clinical practice and self-care. The goals of this article are to provide historical context for the regulation and science of dietary supplements, identify research resources, and suggest some future directions for science in this field., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2024
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17. Effect of Holstein genotype on ex-vivo interleukin-1β response to lipopolysaccharide (LPS), lipoteichoic acid (LTA) and heat-killed Gram-negative and Gram-positive bacteria.
- Author
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Brink AA, Weber WJ, Lippolis JD, Cole JB, Rendahl AK, Caixeta L, Godden SM, Seykora AJ, and Crooker BA
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- Female, Animals, Cattle, Staphylococcus aureus, Interleukin-1beta genetics, Hot Temperature, Teichoic Acids pharmacology, Gram-Negative Bacteria, Genotype, Lipopolysaccharides pharmacology, Escherichia coli
- Abstract
Effects of Holstein genotype on interleukin-1β response were assessed by ex-vivo stimulation of whole blood with lipopolysaccharide (LPS), lipoteichoic acid (LTA), or sonicated, heat-killed Gram-negative or Gram-positive bacteria. Holstein genotypes were unselected Holsteins (UH, n = 14) not subjected to selection pressures since the mid-1960s and contemporary Holsteins (CH, n = 13). Milk yield of UH and CH cows differ by more than 4500 kg/lactation. Whole blood was mixed with 0.01 µg LPS, 10 µg LTA or 2.5 × 10
6 CFU of sonicated, heat-killed E. coli, K. pneumoniae, S. marcescens, S. aureus, S. dysgalactiae, or S. uberis per mL of blood and incubated (4 h, 37 °C). Plasma IL-1β was quantified by ELISA and log10 -transformed concentrations analyzed with a multivariate linear mixed effects model. Responses to bacteria were greater than responses to LPS or LTA. Responses to LPS, LTA and the Gram-negative stimulants were greater in UH than in CH cows while responses to the Gram-positive bacteria did not differ between Holstein genotypes. In both genotypes, strong correlations were detected among IL-1β responses to the Gram-negative stimulants and to LTA. There were strong correlations among IL-1β responses to the Gram-positive bacteria in CH cows but only between S. aureus and S. dysgalactiae in UH cows. The IL-1β response to S. uberis was highly correlated with responses to all of the Gram-negative stimulants in CH cows but only with E. coli in the UH cows. The reduced immune response could make contemporary cows more susceptible to infection by Gram-negative bacteria. Results confirm selection practices since the mid-1960s have altered immune response in the Holstein, at least to Gram-negative bacteria, and validate the need for additional studies to further evaluate the impacts of these selection practices on immune function in contemporary Holsteins., Competing Interests: Declaration of Competing Interest The authors have not stated any conflicts of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)- Published
- 2023
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18. Effect of Holstein genotype on ex-vivo cytokine response to lipopolysaccharide (LPS) and lipoteichoic acid (LTA) during the periparturient period.
- Author
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Brink AA, Weber WJ, Lippolis JD, Cole JB, Godden SM, Seykora A, and Crooker BA
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- Animals, Cattle, Female, Genotype, Pathogen-Associated Molecular Pattern Molecules, Teichoic Acids pharmacology, Cytokines genetics, Lipopolysaccharides pharmacology
- Abstract
Effects of Holstein genotype on innate immune response were assessed with ex-vivo lipopolysaccharide (LPS) and lipoteichoic acid (LTA) stimulation of whole blood from unselected (UH, n = 10) and contemporary (CH, n = 11) Holsteins that differ in production by more than 4,500 kg/lactation. Blood was collected at -14, 7, 28, and 49 days in milk (DIM), mixed with a pathogen-associated molecular pattern (PAMP) molecule (0.01 or 1.0 µg LPS or 10 or 100 µg LTA per mL blood) and incubated (4 h, 37 °C). Plasma cytokines were quantified by ELISA, log
10 -transformed and analyzed by repeated measures with DIM as the repeated effect. Cytokine responses increased with PAMP dose and decreased as DIM increased. There was a genotype by LPS dose interaction for IL-1β as response to the low dose was greater in UH but did not differ between genotypes for the high dose. The IL-1β response was greater while the IL-6 response to LTA tended to be greater in UH than in CH cows. The more negative energy balance of CH cows did not impact genotype difference in cytokine responses. Results indicate selection since the mid-1960s has decreased ex-vivo, whole blood cytokine response of CH cows to LPS and to LTA., (Copyright © 2022. Published by Elsevier B.V.)- Published
- 2022
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19. Effect of Holstein genotype on immune response to an intramammary Escherichia coli challenge.
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Lippolis JD, Putz EJ, Reinhardt TA, Casas E, Weber WJ, and Crooker BA
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- Animals, Cattle, Escherichia coli, Female, Genotype, Immunity, Innate genetics, Interleukin-6 metabolism, Mammary Glands, Animal metabolism, Milk metabolism, Cattle Diseases metabolism, Escherichia coli Infections veterinary, Mastitis, Bovine microbiology
- Abstract
Selective breeding of US dairy cows since the mid-1960s has contributed to remarkable gains in milk yield per cow. This increased milk yield has been associated with an increase in health issues. Since 1964, the University of Minnesota has selectively bred a Holstein herd to maintain genetically static, unselected Holsteins (UH). Comparison of these UH cows with contemporary Holsteins (CH) has demonstrated that the UH cows not only produce less milk but also have fewer health concerns than their CH herdmates. The objective of this study was to determine the effects of Holstein genotype on innate immune response in an experimental intramammary Escherichia coli challenge model. Primiparous UH (n = 5) and CH (n = 7) cows received 430 cfu of E. coli strain P4 in 1 quarter. Blood and affected quarter milk samples were collected at 0, 0.25, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 7, 9, and 11 d relative to E. coli infusion. Rectal temperatures were recorded at each milking through d 4 of the experiment. Milk bacterial counts, somatic cell count and BSA concentrations, complete blood cell counts, rectal temperature, and serum and milk whey cytokine (IL-1β and IL-6) concentrations were used as metrics to determine infection severity. Longitudinal (repeated) data were analyzed using general linear models with PROC MIXED with day of study as the repeated effect. Whole blood transcriptomes were generated by RNA sequencing. Transcripts with a false discovery rate of P < 0.05 and a delta log
2 expression value greater than 0.7 or less than -0.7 were used for functional enrichment analysis. Bacterial counts were consistently greater in milk from CH than UH cows from d 0.25 through d 2.5. Milk somatic cell count increased within 6 h (d 0.25) after E. coli administration in CH and UH cows but did not differ between genotypes after d 1. Rectal body temperature peaked at d 1 in CH and UH cows but was greater in CH cows. Milk BSA, IL-1β, and IL-6 concentrations were greater in CH than UH cows after E. coli administration. Blood lymphocyte and neutrophil counts were decreased at 0.5 and 1 d in CH but not in UH cows. The number of differentially expressed transcripts at each of the postinfusion sampling times was consistently greater (4- to 90-fold) in CH than in UH cows. A key difference between the immune reaction of the 2 genotypes was that the immune response to E. coli was largely contained within the mammary gland of the UH cows but became more systemic in the CH cows. These data demonstrate that UH cows exerted more effective control of E. coli infused into the mammary gland and thus support the hypothesis that selection practices since the mid-1960s have resulted in CH cows with an immune system that is less effective in fighting intramammary infections. Identification of genetic factors associated with enhanced immune functions that differ between the UH and CH cows could contribute to efforts to reintroduce or enhance beneficial components that have been lost or reduced in the CH cows since the mid-1960s., (© 2022, The Authors. Published by Elsevier Inc. and Fass Inc. on behalf of the American Dairy Science Association®. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).)- Published
- 2022
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20. Tunable Chemical Disorder in Concentrated Alloys: Defect Physics and Radiation Performance.
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Zhang Y, Osetsky YN, and Weber WJ
- Abstract
The development of advanced structural alloys with performance meeting the requirements of extreme environments in nuclear reactors has been long pursued. In the long history of alloy development, the search for metallic alloys with improved radiation tolerance or increased structural strength has relied on either incorporating alloying elements at low concentrations to synthesize so-called dilute alloys or incorporating nanoscale features to mitigate defects. In contrast to traditional approaches, recent success in synthesizing multicomponent concentrated solid-solution alloys (CSAs), including medium-entropy and high-entropy alloys, has vastly expanded the compositional space for new alloy discovery. Their wide variety of elemental diversity enables tunable chemical disorder and sets CSAs apart from traditional dilute alloys. The tunable electronic structure critically lowers the effectiveness of energy dissipation via the electronic subsystem. The tunable chemical complexity also modifies the scattering mechanisms in the atomic subsystem that control energy transport through phonons. The level of chemical disorder depends substantively on the specific alloying elements, rather than the number of alloying elements, as the disorder does not monotonically increase with a higher number of alloying elements. To go beyond our knowledge based on conventional alloys and take advantage of property enhancement by tuning chemical disorder, this review highlights synergistic effects involving valence electrons and atomic-level and nanoscale inhomogeneity in CSAs composed of multiple transition metals. Understanding of the energy dissipation pathways, deformation tolerance, and structural stability of CSAs can proceed by exploiting the equilibrium and non-equilibrium defect processes at the electronic and atomic levels, with or without microstructural inhomogeneities at multiple length scales. Knowledge of tunable chemical disorder in CSAs may advance the understanding of the substantial modifications in element-specific alloy properties that effectively mitigate radiation damage and control a material's response in extreme environments, as well as overcome strength-ductility trade-offs and provide overarching design strategies for structural alloys.
- Published
- 2022
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21. Forming 4-Methylcatechol as the Dominant Bioavailable Metabolite of Intraruminal Rutin Inhibits p -Cresol Production in Dairy Cows.
- Author
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Guo Y, Weber WJ, Yao D, Caixeta L, Zimmerman NP, Thompson J, Block E, Rehberger TG, Crooker BA, and Chen C
- Abstract
Rutin, a natural flavonol glycoside, elicits its diverse health-promoting effects from the bioactivities of quercetin, its aglycone. While widely distributed in the vegetables and fruits of human diet, rutin is either absent or inadequate in common animal feed ingredients. Rutin has been supplemented to dairy cows for performance enhancement, but its metabolic fate in vivo has not been determined. In this study, plasma, urine, and rumen fluid samples were collected before and after the intraruminal dosing of 100 mg/kg rutin to 4 Holsteins, and then characterized by both targeted and untargeted liquid chromatography-mass spectrometry (LC-MS)-based metabolomic analysis. In plasma and urine, 4-methylcatechol sulfate was identified as the most abundant metabolite of rutin, instead of quercetin and its flavonol metabolites, and its concentration was inversely correlated with the concentration of p -cresol sulfate. In rumen fluid, the formation of 3,4-dihydroxyphenylacetic acid (DHPAA) and 4-methylcatechol after rapid degradation of rutin and quercetin concurred with the decrease of p -cresol and the increase of its precursor, 4-hydroxyphenylacetic acid. Overall, the formation of 4-methylcatechol, a bioactive microbial metabolite, as the dominant bioavailable metabolite of rutin and quercetin, could contribute to their beneficial bioactivities in dairy cows, while the decrease of p -cresol, a microbial metabolite with negative biological and sensory properties, from the competitive inhibition between microbial metabolism of rutin and tyrosine, has the potential to reduce environmental impact of dairy operations and improve the health of dairy cattle.
- Published
- 2021
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22. Ion irradiation induced strain and structural changes in LiTaO 3 perovskite.
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Zhang FX, Velisa G, Xue H, Sellami N, Trautmann C, Zhang Y, and Weber WJ
- Abstract
LiTaO
3 crystals irradiated with 3 MeV and 1.162 GeV Au ions were studied by single crystal x-ray diffraction and Raman scattering measurements. The maximum lattice strains after 3 MeV Au ion irradiation to a fluence of 1.2 × 1013 cm-2 were 1.2% and 0.6% along the c - and a -/ b -axes, respectively. Two effects were observed in 1.162 GeV Au ion irradiated samples: (i) the (0006) and (1120) Bragg peaks were split into doublets, which suggested a subtle structural change due to slight modification of chemical composition; and (ii) the pre-damaged 1.2% lattice strain along the c -axis was relaxed to 0.9% after subsequent irradiation with 1.162 GeV Au ions, while relaxation along the a - or b -axis was not obvious. A distinct change in the Raman spectrum of the 〈0001〉 oriented LiTaO3 crystals was observed after 1.162 GeV Au ion irradiation, but no obvious change was observed in the 〈1120〉 oriented samples or in 3 MeV Au ion irradiated samples. Strain and structural changes in crystalline LiTaO3 , with or without pre-existing defects, upon ion irradiation are delineated in its responding to inelastic ionization and elastic nuclear collisions., (© 2021 IOP Publishing Ltd.)- Published
- 2021
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23. Sensor Noise in LISA Pathfinder: In-Flight Performance of the Optical Test Mass Readout.
- Author
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Armano M, Audley H, Baird J, Binetruy P, Born M, Bortoluzzi D, Brandt N, Castelli E, Cavalleri A, Cesarini A, Cruise AM, Danzmann K, de Deus Silva M, Diepholz I, Dixon G, Dolesi R, Ferraioli L, Ferroni V, Fitzsimons ED, Flatscher R, Freschi M, García A, Gerndt R, Gesa L, Giardini D, Gibert F, Giusteri R, Grimani C, Grzymisch J, Guzman F, Harrison I, Hartig MS, Heinzel G, Hewitson M, Hollington D, Hoyland D, Hueller M, Inchauspé H, Jennrich O, Jetzer P, Johann U, Johlander B, Karnesis N, Kaune B, Killow CJ, Korsakova N, Lobo JA, Liu L, López-Zaragoza JP, Maarschalkerweerd R, Mance D, Martín V, Martin-Polo L, Martin-Porqueras F, Martino J, McNamara PW, Mendes J, Mendes L, Meshksar N, Monsky A, Nofrarias M, Paczkowski S, Perreur-Lloyd M, Petiteau A, Pivato P, Plagnol E, Ramos-Castro J, Reiche J, Rivas F, Robertson DI, Russano G, Sanjuan J, Slutsky J, Sopuerta CF, Steier F, Sumner T, Texier D, Thorpe JI, Vetrugno D, Vitale S, Wand V, Wanner G, Ward H, Wass PJ, Weber WJ, Wissel L, Wittchen A, and Zweifel P
- Abstract
We report on the first subpicometer interferometer flown in space. It was part of ESA's Laser Interferometer Space Antenna (LISA) Pathfinder mission and performed the fundamental measurement of the positional and angular motion of two free-falling test masses. The interferometer worked immediately, stably, and reliably from switch on until the end of the mission with exceptionally low residual noise of 32.0_{-1.7}^{+2.4} fm/sqrt[Hz], significantly better than required. We present an upper limit for the sensor performance at millihertz frequencies and a model for the measured sensitivity above 200 mHz.
- Published
- 2021
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24. Irradiation-Induced Extremes Create Hierarchical Face-/Body-Centered-Cubic Phases in Nanostructured High Entropy Alloys.
- Author
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Jiang L, Hu YJ, Sun K, Xiu P, Song M, Zhang Y, Boldman WL, Crespillo ML, Rack PD, Qi L, Weber WJ, and Wang L
- Abstract
A nanoscale hierarchical dual-phase structure is reported to form in a nanocrystalline NiFeCoCrCu high-entropy-alloy (HEA) film via ion irradiation. Under the extreme energy deposition and consequent thermal energy dissipation induced by energetic particles, a fundamentally new phenomenon is revealed, in which the original single-phase face-centered-cubic (FCC) structure partially transforms into alternating nanometer layers of a body-centered-cubic (BCC) structure. The orientation relationship follows the Nishiyama-Wasser-man relationship, that is, (011)
BCC || ( 1¯1¯1)FCC and [100]BCC || [ 11¯0]FCC . Simulation results indicate that Cr, as a BCC stabilizing element, exhibits a tendency to segregate to the stacking faults (SFs). Furthermore, the high densities of SFs and twin boundaries in each nanocrystalline grain serve to accelerate the nucleation and growth of the BCC phase during irradiation. By adjusting the irradiation parameters, desired thicknesses of the FCC and BCC phases in the laminates can be achieved. This work demonstrates the controlled formation of an attractive dual-phase nanolaminate structure under ion irradiation and provides a strategy for designing new derivate structures of HEAs., (© 2020 Wiley-VCH GmbH.)- Published
- 2020
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25. National Center for Complementary and Integrative Health Perspectives on Clinical Research Involving Natural Products.
- Author
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Weber WJ and Hopp DC
- Subjects
- Biological Products administration & dosage, Clinical Trials as Topic economics, Humans, National Center for Complementary and Integrative Health (U.S.) economics, Policy, United States, Biological Products adverse effects, Clinical Trials as Topic standards, Dietary Supplements adverse effects, National Center for Complementary and Integrative Health (U.S.) standards, Research Design standards
- Abstract
The sales of dietary supplements continue to increase year after year. Despite their use by a large percentage of Americans, there is little evidence for the vast majority of products regarding their safety or efficacy. National Center for Complementary and Integrative Health supports a broad range of research on dietary supplements, including clinical trials. Our experience with these trials has shaped our current policies and priorities for clinical research. This perspective outlines those policies and priorities that are shaping our investments going forward. SIGNIFICANCE STATEMENT: The sales of dietary supplements continue to increase year after year. Despite their use by a large percentage of Americans, there is little evidence for the vast majority of products regarding their safety or efficacy. National Center for Complementary and Integrative Health supports a broad range of research on dietary supplements, including clinical trials. Our experience with these trials has shaped our current policies and priorities for clinical research. This perspective outlines those policies and priorities that are shaping our investments going forward., (U.S. Government work not protected by U.S. copyright.)
- Published
- 2020
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- View/download PDF
26. Symmetry degeneration and room temperature ferroelectricity in ion-irradiated SrTiO 3 .
- Author
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Zhang FX, Xue H, Keum JK, Boulle A, Zhang Y, and Weber WJ
- Abstract
Polar phonon modes associated with room temperature ferroelectricity are observed in SrTiO
3 single crystals irradiated with Ti ions. Quantitative strain analysis reveals that irradiation-induced out-of-plane strain drives the centrosymmetric cubic SrTiO3 to a tetragonal-like structure in the maximum damaged region. Energy transfer from ions to electrons during ion irradiation yields defects in SrTiO3 that also plays an important role for the room temperature ferroelectricity. Different from thin film techniques, the ferroelectricity in the ion irradiated SrTiO3 can occur for much larger thicknesses, depending on the energy and type of ion., (© 2020 IOP Publishing Ltd.)- Published
- 2020
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27. Effects of anionic supplement source in prepartum negative dietary cation-anion difference diets on serum calcium, feed intake, and lactational performance of multiparous dairy cows.
- Author
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Caixeta LS, Weber WJ, Johnson DM, Faser J, Visser BM, and Crooker BA
- Subjects
- Animals, Anions administration & dosage, Diet veterinary, Dietary Supplements analysis, Female, Parity, Random Allocation, Animal Feed analysis, Anions metabolism, Calcium blood, Cattle physiology, Eating, Lactation
- Abstract
Incidence of subclinical hypocalcemia in early postpartum dairy cows continues to be an animal welfare concern and an economic burden for producers. Feeding prepartum negative dietary cation-anion difference (DCAD) diets produces metabolic acidosis, which supports mobilization of bone calcium and reduces the incidence of hypocalcemia. Achieving a sufficient degree of metabolic acidosis without reducing dry matter intake (DMI) can be difficult. This study compared the ability of MegAnion (MA; Origination O2D Inc., Maplewood, MN), a new DCAD supplement designed to be more palatable than typical anionic salt sources, and another palatable commercial DCAD product, SoyChlor (SC; Landus Cooperative, Ralston, IA), to reduce urine pH (a surrogate for metabolic acidosis) without reducing prepartum DMI. A secondary objective was to assess the effect of these anionic supplements on postpartum serum calcium concentrations and DMI. Prepartum multiparous Holstein (HO) and crossbred (XX) cows were blocked by breed and expected calving date and randomly assigned within breed to total mixed rations (TMR) with MA or SC and DCAD values of -215 mEq/kg of DM. Cows (n = 56; 15 MA-HO, 12 SC-HO, 15 MA-XX, 14 SC-XX) consumed the treatment TMR for at least 19 d and completed the 28 d in milk (DIM) phase of the study. Urine and blood samples were collected weekly and at 1, 2, and 3 DIM. Data were analyzed as a randomized block design by repeated measures with week or DIM as the repeated effect. Prepartum urine pH decreased from 8.15 ± 0.27 before treatment to 6.12 ± 0.14 during treatment, was not affected by anionic supplement, and increased immediately after calving when all cows consumed the same early-lactation TMR. Prepartum serum calcium concentrations were not affected (2.34 vs. 2.33 ± 0.02 mmol/L) by treatment, whereas nonesterified fatty acids were lower (86 vs. 120 ± 10 mmol/L) and insulin was greater (215 vs. 174 ± 10 pmol/L) in cows fed MA than in cows fed SC. These differences are supported by the numerically greater prepartum DMI (1.2 kg/d) and energy balance (1.8 Mcal/d) of cows fed MA. However, pre- and postpartum DMI and other production variables, including body weight, body condition score, milk yield, and energy balance, were not affected by treatment. This lack of difference indicates that MA provides another effective source of anionic salts for diets designed to reduce urine pH and induce metabolic acidosis in prepartum dairy cows., (Copyright © 2020 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)
- Published
- 2020
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28. Analysis of the accuracy of actuation electronics in the laser interferometer space antenna pathfinder.
- Author
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Armano M, Audley H, Baird J, Born M, Bortoluzzi D, Cardines N, Castelli E, Cavalleri A, Cesarini A, Cruise AM, Danzmann K, de Deus Silva M, Dixon G, Dolesi R, Ferraioli L, Ferroni V, Fitzsimons ED, Freschi M, Gesa L, Giardini D, Gibert F, Giusteri R, Grimani C, Grzymisch J, Harrison I, Hartig MS, Heinzel G, Hewitson M, Hollington D, Hoyland D, Hueller M, Inchauspé H, Jennrich O, Jetzer P, Karnesis N, Kaune B, Killow CJ, Korsakova N, López-Zaragoza JP, Maarschalkerweerd R, Mance D, Martín V, Martin-Polo L, Martino J, Martin-Porqueras F, Mateos I, McNamara PW, Mendes J, Mendes L, Meshksar N, Nofrarias M, Paczkowski S, Perreur-Lloyd M, Petiteau A, Pivato P, Plagnol E, Ramos-Castro J, Reiche J, Rivas F, Robertson DI, Russano G, Slutsky J, Sopuerta CF, Sumner T, Texier D, Ten Pierick J, Thorpe JI, Vetrugno D, Vitale S, Wanner G, Ward H, Wass PJ, Weber WJ, Wissel L, Wittchen A, and Zweifel P
- Abstract
The Laser Interferometer Space Antenna Pathfinder (LPF) main observable, labeled Δg, is the differential force per unit mass acting on the two test masses under free fall conditions after the contribution of all non-gravitational forces has been compensated. At low frequencies, the differential force is compensated by an applied electrostatic actuation force, which then must be subtracted from the measured acceleration to obtain Δg. Any inaccuracy in the actuation force contaminates the residual acceleration. This study investigates the accuracy of the electrostatic actuation system and its impact on the LPF main observable. It is shown that the inaccuracy is mainly caused by the rounding errors in the waveform processing and also by the random error caused by the analog to digital converter random noise in the control loop. Both errors are one order of magnitude smaller than the resolution of the commanded voltages. We developed a simulator based on the LPF design to compute the close-to-reality actuation voltages and, consequently, the resulting actuation forces. The simulator is applied during post-processing the LPF data.
- Published
- 2020
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29. Interpreting nanovoids in atom probe tomography data for accurate local compositional measurements.
- Author
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Wang X, Hatzoglou C, Sneed B, Fan Z, Guo W, Jin K, Chen D, Bei H, Wang Y, Weber WJ, Zhang Y, Gault B, More KL, Vurpillot F, and Poplawsky JD
- Abstract
Quantifying chemical compositions around nanovoids is a fundamental task for research and development of various materials. Atom probe tomography (APT) and scanning transmission electron microscopy (STEM) are currently the most suitable tools because of their ability to probe materials at the nanoscale. Both techniques have limitations, particularly APT, because of insufficient understanding of void imaging. Here, we employ a correlative APT and STEM approach to investigate the APT imaging process and reveal that voids can lead to either an increase or a decrease in local atomic densities in the APT reconstruction. Simulated APT experiments demonstrate the local density variations near voids are controlled by the unique ring structures as voids open and the different evaporation fields of the surrounding atoms. We provide a general approach for quantifying chemical segregations near voids within an APT dataset, in which the composition can be directly determined with a higher accuracy than STEM-based techniques.
- Published
- 2020
- Full Text
- View/download PDF
30. Local structure of Ni 80 X 20 (X: Cr, Mn, Pd) solid-solution alloys and its response to ion irradiation.
- Author
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Zhang FX, Tong Y, Velisa G, Bei H, Weber WJ, and Zhang Y
- Abstract
The local structure of Ni
80 X20 (X: Cr, Mn, Pd) solid-solution alloys was investigated with x-ray absorption and total scattering x-ray diffraction methods. Atomic pair distribution function (PDF) analysis indicated that the local lattice distortion is strongly relevant to the atomic size mismatch, and the local lattice distortion in Ni80 Pd20 alloy is obviously larger than that in other solid-solution alloys. The bond length of different atomic pairs was derived from the fitting of extended x-ray absorption fine structure spectra. Quantitative analysis of the local bonding environment in Ni80 Cr20 during Ni ion irradiation suggested that Cr atoms tend to form clusters in Ni80 Cr20 with the increase of ion dose.- Published
- 2020
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- View/download PDF
31. Effect of Holstein genotype on innate immune and metabolic responses of heifers to lipopolysaccharide (LPS) administration.
- Author
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Cousillas-Boam G, Weber WJ, Benjamin A, Kahl S, Heins BJ, Elsasser TH, Kerr DE, and Crooker BA
- Subjects
- Animals, Female, Fibroblasts drug effects, Interleukin-6 administration & dosage, Interleukin-6 pharmacology, Interleukin-8 administration & dosage, Interleukin-8 pharmacology, Cattle genetics, Cattle immunology, Genotype, Immunity, Innate genetics, Lipopolysaccharides toxicity
- Abstract
Heifers (n = 4/genotype) from unselected (stable genotype since 1964, UH) and contemporary (CH) Holsteins that differed in milk yield (6,200 and 11,100 kg milk/305 d) were used to assess the impact of selection on innate immune and acute-phase response to an endotoxin (lipopolysaccharide; LPS). Jugular catheters were implanted 24 h before LPS administration. Blood samples were collected at -1, -0.5, 0, 1, 2, 3, 4, 6, 8, and 24 h relative to iv administration of 0.5 μg LPS/kg BW. Rectal body temperature (BT) was determined at these sampling times and at 5 and 7 h. Dermal biopsies were collected after the 24 h blood sample and processed to isolate fibroblasts. Plasma was analyzed for tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), serum amyloid A (SAA), xanthine oxidase (XO), and nitrate + nitrite (NOx), cortisol, glucose, and IGF-1 content. Isolated fibroblasts were exposed to IL-1β or LPS and IL-6 and IL-8 content of culture media determined. Exposure to LPS increased BTs and plasma concentrations of TNF-α, IL-6 SAA, XO, cortisol, and glucose (P < 0.05) in both genotypes. Plasma concentrations of TNF-α, XO, NOx, and glucose did not differ (P > 0.25) between the genotypes, but IL-6 and SAA concentrations were reduced (P < 0.05) in CH relative to UH heifers while cortisol and IGF-1 concentrations tended (P < 0.08) to be reduced in CH heifers. After 36 h exposure to LPS, concentrations of IL-6 were greater (P < 0.05) in culture media from incubations of CH than UH fibroblasts but concentrations of IL-8 did not differ between genotypes. There was a trend (P = 0.08) for IL-8 concentrations to be reduced in media from CH fibroblasts exposed to IL-1β for 24 h but IL-6 concentrations did not differ between genotypes. Results indicate 50 yr of selection has reduced the robustness of the innate immune and acute-phase response to LPS in the contemporary Holstein heifer., (Copyright © 2019 Elsevier Inc. All rights reserved.)
- Published
- 2020
- Full Text
- View/download PDF
32. LISA Pathfinder Performance Confirmed in an Open-Loop Configuration: Results from the Free-Fall Actuation Mode.
- Author
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Armano M, Audley H, Baird J, Binetruy P, Born M, Bortoluzzi D, Castelli E, Cavalleri A, Cesarini A, Cruise AM, Danzmann K, de Deus Silva M, Diepholz I, Dixon G, Dolesi R, Ferraioli L, Ferroni V, Fitzsimons ED, Freschi M, Gesa L, Gibert F, Giardini D, Giusteri R, Grimani C, Grzymisch J, Harrison I, Hartig MS, Heinzel G, Hewitson M, Hollington D, Hoyland D, Hueller M, Inchauspé H, Jennrich O, Jetzer P, Karnesis N, Kaune B, Korsakova N, Killow CJ, Lobo JA, Liu L, López-Zaragoza JP, Maarschalkerweerd R, Mance D, Meshksar N, Martín V, Martin-Polo L, Martino J, Martin-Porqueras F, Mateos I, McNamara PW, Mendes J, Mendes L, Nofrarias M, Paczkowski S, Perreur-Lloyd M, Petiteau A, Pivato P, Plagnol E, Ramos-Castro J, Reiche J, Robertson DI, Rivas F, Russano G, Slutsky J, Sopuerta CF, Sumner T, Texier D, Thorpe JI, Vetrugno D, Vitale S, Wanner G, Ward H, Wass PJ, Weber WJ, Wissel L, Wittchen A, and Zweifel P
- Abstract
We report on the results of the LISA Pathfinder (LPF) free-fall mode experiment, in which the control force needed to compensate the quasistatic differential force acting on two test masses is applied intermittently as a series of "impulse" forces lasting a few seconds and separated by roughly 350 s periods of true free fall. This represents an alternative to the normal LPF mode of operation in which this balancing force is applied continuously, with the advantage that the acceleration noise during free fall is measured in the absence of the actuation force, thus eliminating associated noise and force calibration errors. The differential acceleration noise measurement presented here with the free-fall mode agrees with noise measured with the continuous actuation scheme, representing an important and independent confirmation of the LPF result. An additional measurement with larger actuation forces also shows that the technique can be used to eliminate actuation noise when this is a dominant factor.
- Published
- 2019
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33. Effect of bovine genotype on innate immune response of heifers to repeated lipopolysaccharide (LPS) administration.
- Author
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Boam GC, Weber WJ, Benjamin A, Kahl S, Allen Bridges G, Elsasser TH, Kerr D, and Crooker BA
- Subjects
- Animals, Cattle genetics, Cattle Diseases immunology, Dairying, Female, Genotype, Inflammation immunology, Lipopolysaccharides administration & dosage, Lipopolysaccharides immunology, Pilot Projects, Cattle immunology, Immunity, Innate genetics
- Abstract
This pilot study provides a preliminary assessment of the impact of genotype on acute innate immune pro-inflammatory, metabolic and endocrine responses to repeated lipopolysaccharide (LPS) administered to growing heifers. Heifers (n = 4/genotype) were from unselected (stable milk yield since 1964, UH) or contemporary (CH) Holstein cows that differed in milk yield (6200 vs 11,100 kg milk/305 d) or from contemporary Black Angus (CA) cows bred to contemporary Red Angus bulls. Heifers were challenged with iv administration of 0.5 μg LPS/kg body weight on day 1 (Challenge 1) and d 5 (Challenge 2) of study to assess endotoxin tolerance. Plasma was collected at -1, -0.5, 0, 1, 2, 3, 4, 6, 8, and 24 h relative to each LPS administration. Rectal body temperature (BT) was measured before each blood sampling and at 5 and 7 h. Data were analyzed by repeated measures with sampling time as the repeated effect. Each genotype had at least one pro-inflammatory response that indicated it might have a more robust response than the other genotypes. The CH heifers had a greater TNF-α response, UH heifers had greater IL-6 and XO responses and CA heifers had greater BT and SAA response to LPS than the other genotypes. There was a genotype by time by interaction as cortisol peaked earlier in CH and UH than in CA heifers. Glucose response was less in CA and insulin response was greater in CH heifers. Endotoxin tolerance to LPS was evident as pro-inflammatory, cortisol, glucose and insulin responses were less during Challenge 2 than during Challenge 1. Differences among genotypes during Challenge 1 were eliminated during Challenge 2 except for the greater SAA response in CA heifers and indicate the potential for differential impacts of genotype on the development of endotoxin tolerance. Specific reasons for these effects of genotype are not clear from these data but the results support the hypothesis for differential innate immune signaling among these bovine genotypes., (Copyright © 2019 Elsevier B.V. All rights reserved.)
- Published
- 2019
- Full Text
- View/download PDF
34. Thermal stability and irradiation response of nanocrystalline CoCrCuFeNi high-entropy alloy.
- Author
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Zhang Y, Tunes MA, Crespillo ML, Zhang F, Boldman WL, Rack PD, Jiang L, Xu C, Greaves G, Donnelly SE, Wang L, and Weber WJ
- Abstract
Grain growth and phase stability of a nanocrystalline face-centered cubic (fcc) Ni
0.2 Fe0.2 Co0.2 Cr0.2 Cu0.2 high-entropy alloy (HEA), either thermally- or irradiation-induced, are investigated through in situ and post-irradiation transmission electron microscopy (TEM) characterization. Synchrotron and lab x-ray diffraction measurements are carried out to determine the microstructural evolution and phase stability with improved statistics. Under in situ TEM observation, the fcc structure is stable at 300 °C with a small amount of grain growth from 15.8 to ∼20 nm being observed after 1800 s. At 500 °C, however, some abnormal growth activities are observed after 1400 s, and secondary phases are formed. Under 3 MeV Ni room temperature ion irradiation up to an extreme dose of nearly 600 displacements per atom, the fcc phase is stable and the average grain size increases from 15.6 to 25.2 nm. Grain growth mechanisms driven by grain rotation, grain boundary curvature, and disorder are discussed.- Published
- 2019
- Full Text
- View/download PDF
35. Pragmatic clinical trials offer unique opportunities for disseminating, implementing, and sustaining evidence-based practices into clinical care: Proceedings of a workshop.
- Author
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Tuzzio L, Larson EB, Chambers DA, Coronado GD, Curtis LH, Weber WJ, Zatzick DF, and Meyers CM
- Subjects
- Education organization & administration, Evidence-Based Practice trends, Humans, Information Dissemination methods, National Institutes of Health (U.S.) organization & administration, Program Evaluation methods, Research Design trends, United States, Evidence-Based Practice methods, Pragmatic Clinical Trials as Topic
- Abstract
The National Institutes of Health (NIH) Health Care Systems (HCS) Research Collaboratory hosted a workshop to explore challenges and strategies for the dissemination, implementation, and sustainability of findings from pragmatic clinical trials (PCTs) embedded in HCS. PCTs are designed to assess the impact of interventions delivered in usual or real-world conditions and leverage existing infrastructure to answer important clinical questions. The goal of the workshop was to discuss strategies for conducting impactful future PCTs that bridge the gap between evidence, practice, and policy. This paper summarizes presentations about how to design and conduct PCTs embedded in HCS and use dissemination and implementation strategies during the planning and conduct of projects, emphasizing the ever-changing world of care delivery and the need for pragmatic trial operations to adapt at various levels of operation., (Copyright © 2019 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2019
- Full Text
- View/download PDF
36. QuanTP: A Software Resource for Quantitative Proteo-Transcriptomic Comparative Data Analysis and Informatics.
- Author
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Kumar P, Panigrahi P, Johnson J, Weber WJ, Mehta S, Sajulga R, Easterly C, Crooker BA, Heydarian M, Anamika K, Griffin TJ, and Jagtap PD
- Subjects
- Animals, High-Throughput Nucleotide Sequencing, Humans, Mass Spectrometry, Computational Biology methods, Data Analysis, Gene Expression Profiling methods, Proteomics methods, Software
- Abstract
Next-generation sequencing technologies, coupled to advances in mass-spectrometry-based proteomics, have facilitated system-wide quantitative profiling of expressed mRNA transcripts and proteins. Proteo-transcriptomic analysis compares the relative abundance levels of transcripts and their corresponding proteins, illuminating discordant gene product responses to perturbations. These results reveal potential post-transcriptional regulation, providing researchers with important new insights into underlying biological and pathological disease mechanisms. To carry out proteo-transcriptomic analysis, researchers require software that statistically determines transcript-protein abundance correlation levels and provides results visualization and interpretation functionality, ideally within a flexible, user-friendly platform. As a solution, we have developed the QuanTP software within the Galaxy platform. The software offers a suite of tools and functionalities critical for proteo-transcriptomics, including statistical algorithms for assessing the correlation between single transcript-protein pairs as well as across two cohorts, outlier identification and clustering, along with a diverse set of results visualizations. It is compatible with analyses of results from single experiment data or from a two-cohort comparison of aggregated replicate experiments. The tool is available in the Galaxy Tool Shed through a cloud-based instance and a Docker container. In all, QuanTP provides an accessible and effective software resource, which should enable new multiomic discoveries from quantitative proteo-transcriptomic data sets.
- Published
- 2019
- Full Text
- View/download PDF
37. Lattice Distortion and Phase Stability of Pd-Doped NiCoFeCr Solid-Solution Alloys.
- Author
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Zhang F, Tong Y, Jin K, Bei H, Weber WJ, and Zhang Y
- Abstract
In the present study, we have revealed that (NiCoFeCr)
100- x Pdx ( x = 1, 3, 5, 20 atom%) high-entropy alloys (HEAs) have both local- and long-range lattice distortions by utilizing X-ray total scattering, X-ray diffraction, and extended X-ray absorption fine structure methods. The local lattice distortion determined by the lattice constant difference between the local and average structures was found to be proportional to the Pd content. A small amount of Pd-doping (1 atom%) yields long-range lattice distortion, which is demonstrated by a larger (200) lattice plane spacing than the expected value from an average structure, however, the degree of long-range lattice distortion is not sensitive to the Pd concentration. The structural stability of these distorted HEAs under high-pressure was also examined. The experimental results indicate that doping with a small amount of Pd significantly enhances the stability of the fcc phase by increasing the fcc-to-hcp transformation pressure from ~13.0 GPa in NiCoFeCr to 20-26 GPa in the Pd-doped HEAs and NiCoFeCrPd maintains its fcc lattice up to 74 GPa, the maximum pressure that the current experiments have reached.- Published
- 2018
- Full Text
- View/download PDF
38. Sculpting Nanoscale Functional Channels in Complex Oxides Using Energetic Ions and Electrons.
- Author
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Sachan R, Zarkadoula E, Ou X, Trautmann C, Zhang Y, Chisholm MF, and Weber WJ
- Abstract
The formation of metastable phases has attracted significant attention because of their unique properties and potential functionalities. In the present study, we demonstrate the phase conversion of energetic-ion-induced amorphous nanochannels/tracks into a metastable defect fluorite in A
2 B2 O7 structured complex oxides by electron irradiation. Through in situ electron irradiation experiments in a scanning transmission electron microscope, we observe electron-induced epitaxial crystallization of the amorphous nanochannels in Yb2 Ti2 O7 into the defect fluorite. This energetic-electron-induced phase transformation is attributed to the coupled effect of ionization-induced electronic excitations and local heating, along with subthreshold elastic energy transfers. We also show the role of ionic radii of A-site cations (A = Yb, Gd, and Sm) and B-site cations (Ti and Zr) in facilitating the electron-beam-induced crystallization of the amorphous phase to the defect-fluorite structure. The formation of the defect-fluorite structure is eased by the decrease in the difference between ionic radii of A- and B-site cations in the lattice. Molecular dynamics simulations of thermal annealing of the amorphous phase nanochannels in A2 B2 O7 draw parallels to the electron-irradiation-induced crystallization and confirm the role of ionic radii in lowering the barrier for crystallization. These results suggest that employing guided electron irradiation with atomic precision is a useful technique for selected area phase formation in nanoscale printed devices.- Published
- 2018
- Full Text
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39. Local structure and defects in ion irradiated KTaO 3 .
- Author
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Zhang FX, Xi J, Zhang Y, Tong Y, Xue H, Huang R, Trautmann C, and Weber WJ
- Abstract
The modification of the local structure in cubic perovskite KTaO
3 irradiated with 3 MeV and 1.1 GeV Au ions is studied by Raman and x-ray absorption spectroscopy, complemented by density functional theory (DFT) calculations. In the case of irradiation with 3 MeV Au ions where displacement cascade processes are dominant, the Ta L3 -edge x-ray absorption measurements suggest that a peak corresponding to the Ta-O bonds in the TaO6 octahedra splits, which is attributed to the formation of TaK antisite defects that are coupled with oxygen vacancies, VO . This finding is consistent with the DFT calculations. Under irradiation with 1.1 GeV ions, the intense ionization and electronic energy deposition lead to a blue shift and an intensity reduction of active Raman bands. In the case of sequential irradiations, extended x-ray absorption fine structure measurements reveal a decrease in concentration of coupled TaK -VO defects under subsequent irradiation with 1.1 GeV Au ions.- Published
- 2018
- Full Text
- View/download PDF
40. Improving atomic displacement and replacement calculations with physically realistic damage models.
- Author
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Nordlund K, Zinkle SJ, Sand AE, Granberg F, Averback RS, Stoller R, Suzudo T, Malerba L, Banhart F, Weber WJ, Willaime F, Dudarev SL, and Simeone D
- Abstract
Atomic collision processes are fundamental to numerous advanced materials technologies such as electron microscopy, semiconductor processing and nuclear power generation. Extensive experimental and computer simulation studies over the past several decades provide the physical basis for understanding the atomic-scale processes occurring during primary displacement events. The current international standard for quantifying this energetic particle damage, the Norgett-Robinson-Torrens displacements per atom (NRT-dpa) model, has nowadays several well-known limitations. In particular, the number of radiation defects produced in energetic cascades in metals is only ~1/3 the NRT-dpa prediction, while the number of atoms involved in atomic mixing is about a factor of 30 larger than the dpa value. Here we propose two new complementary displacement production estimators (athermal recombination corrected dpa, arc-dpa) and atomic mixing (replacements per atom, rpa) functions that extend the NRT-dpa by providing more physically realistic descriptions of primary defect creation in materials and may become additional standard measures for radiation damage quantification.
- Published
- 2018
- Full Text
- View/download PDF
41. Beyond the Required LISA Free-Fall Performance: New LISA Pathfinder Results down to 20 μHz.
- Author
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Armano M, Audley H, Baird J, Binetruy P, Born M, Bortoluzzi D, Castelli E, Cavalleri A, Cesarini A, Cruise AM, Danzmann K, de Deus Silva M, Diepholz I, Dixon G, Dolesi R, Ferraioli L, Ferroni V, Fitzsimons ED, Freschi M, Gesa L, Gibert F, Giardini D, Giusteri R, Grimani C, Grzymisch J, Harrison I, Heinzel G, Hewitson M, Hollington D, Hoyland D, Hueller M, Inchauspé H, Jennrich O, Jetzer P, Karnesis N, Kaune B, Korsakova N, Killow CJ, Lobo JA, Lloro I, Liu L, López-Zaragoza JP, Maarschalkerweerd R, Mance D, Meshksar N, Martín V, Martin-Polo L, Martino J, Martin-Porqueras F, Mateos I, McNamara PW, Mendes J, Mendes L, Nofrarias M, Paczkowski S, Perreur-Lloyd M, Petiteau A, Pivato P, Plagnol E, Ramos-Castro J, Reiche J, Robertson DI, Rivas F, Russano G, Slutsky J, Sopuerta CF, Sumner T, Texier D, Thorpe JI, Vetrugno D, Vitale S, Wanner G, Ward H, Wass PJ, Weber WJ, Wissel L, Wittchen A, and Zweifel P
- Abstract
In the months since the publication of the first results, the noise performance of LISA Pathfinder has improved because of reduced Brownian noise due to the continued decrease in pressure around the test masses, from a better correction of noninertial effects, and from a better calibration of the electrostatic force actuation. In addition, the availability of numerous long noise measurement runs, during which no perturbation is purposely applied to the test masses, has allowed the measurement of noise with good statistics down to 20 μHz. The Letter presents the measured differential acceleration noise figure, which is at (1.74±0.05) fm s^{-2}/sqrt[Hz] above 2 mHz and (6±1)×10 fm s^{-2}/sqrt[Hz] at 20 μHz, and discusses the physical sources for the measured noise. This performance provides an experimental benchmark demonstrating the ability to realize the low-frequency science potential of the LISA mission, recently selected by the European Space Agency.
- Published
- 2018
- Full Text
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42. Effects of chemical alternation on damage accumulation in concentrated solid-solution alloys.
- Author
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Ullah MW, Xue H, Velisa G, Jin K, Bei H, Weber WJ, and Zhang Y
- Abstract
Single-phase concentrated solid-solution alloys (SP-CSAs) have recently gained unprecedented attention due to their promising properties. To understand effects of alloying elements on irradiation-induced defect production, recombination and evolution, an integrated study of ion irradiation, ion beam analysis and atomistic simulations are carried out on a unique set of model crystals with increasing chemical complexity, from pure Ni to Ni
80 Fe20 , Ni50 Fe50 , and Ni80 Cr20 binaries, and to a more complex Ni40 Fe40 Cr20 alloy. Both experimental and simulation results suggest that the binary and ternary alloys exhibit higher radiation resistance than elemental Ni. The modeling work predicts that Ni40 Fe40 Cr20 has the best radiation tolerance, with the number of surviving Frenkel pairs being factors of 2.0 and 1.4 lower than pure Ni and the 80:20 binary alloys, respectively. While the reduced defect mobility in SP-CSAs is identified as a general mechanism leading to slower growth of large defect clusters, the effect of specific alloying elements on suppression of damage accumulation is clearly demonstrated. This work suggests that concentrated solid-solution provides an effective way to enhance radiation tolerance by creating elemental alternation at the atomic level. The demonstrated chemical effects on defect dynamics may inspire new design principles of radiation-tolerant structural alloys for advanced energy systems.- Published
- 2017
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43. Local Structure and Short-Range Order in a NiCoCr Solid Solution Alloy.
- Author
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Zhang FX, Zhao S, Jin K, Xue H, Velisa G, Bei H, Huang R, Ko JYP, Pagan DC, Neuefeind JC, Weber WJ, and Zhang Y
- Abstract
Multielement solid solution alloys are intrinsically disordered on the atomic scale, and many of their advanced properties originate from the local structural characteristics. The local structure of a NiCoCr solid solution alloy is measured with x-ray or neutron total scattering and extended x-ray absorption fine structure (EXAFS) techniques. The atomic pair distribution function analysis does not exhibit an observable structural distortion. However, an EXAFS analysis suggests that the Cr atoms are favorably bonded with Ni and Co in the solid solution alloys. This short-range order (SRO) may make an important contribution to the low values of the electrical and thermal conductivities of the Cr-alloyed solid solutions. In addition, an EXAFS analysis of Ni ion irradiated samples reveals that the degree of SRO in NiCoCr alloys is enhanced after irradiation.
- Published
- 2017
- Full Text
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44. Hepatic mRNA expression for genes related to somatotropic axis, glucose and lipid metabolisms, and inflammatory response of periparturient dairy cows treated with recombinant bovine somatotropin.
- Author
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Silva PRB, Weber WJ, Crooker BA, Collier RJ, Thatcher WW, and Chebel RC
- Subjects
- Animals, Cattle, Fatty Acids, Nonesterified blood, Female, Lactation, Lipid Metabolism, Liver metabolism, Milk metabolism, RNA, Messenger metabolism, Glucose metabolism, Growth Hormone blood
- Abstract
Objectives of this experiment were to evaluate the effects of recombinant bovine somatotropin (rbST) treatment of periparturient dairy cows on hepatic mRNA expression for genes related to the somatotropic axis, insulin, glucose, and lipid metabolism, inflammation, and oxidative stress. Holstein cows were enrolled in the experiment at 253 ± 3 d of gestation and assigned to 1 of 3 treatments: untreated control (n = 53), 87.5 mg of rbST (n = 56; rbST87.5), and 125 mg of rbST (n = 57; rbST125). Cows in the rbST87.5 and rbST125 treatments received weekly injections of rbST from -21 to 28 d relative to calving. A subsample of cows (control = 20, rbST87.5 = 20, rbST125 = 20) was randomly selected for collection of liver samples according to expected calving date, BCS, and previous lactation 305-d mature equivalent milk yield. Only cows that had liver sampled at -21 ± 3, -7 ± 3, and 7 ± 3 d relative to calving were used in the current experiment. Blood, sampled weekly from -28 to 21 d relative to calving, was used to determine the concentrations of growth hormone, insulin-like growth factor 1, insulin, cortisol, fatty acids, β-hydroxybutyrate, glucose, haptoglobin, and tumor necrosis factor-α. Liver samples were used to determine hepatic mRNA expression of 50 genes. Treatment with rbST increased growth hormone concentrations during the postpartum period (control = 9.0 ± 0.7, rbST87.5 = 15.3 ± 1.0, rbST125 = 18.5 ± 1.3 ng/mL) and increased insulin-like growth factor 1 concentrations during the prepartum period (control = 107.4 ± 7.2, rbST87.5 = 126.9 ± 6.6, rbST125 = 139.4 ± 6.9 ng/mL). Control cows had greater postpartum concentrations of β-hydroxybutyrate (control = 776.4 ± 64.0, rbST87.5 = 628.4 ± 59.7, rbST125 = 595.4 ± 60.9 µmol/L) than rbST cows. The rbST87.5 and rbST125 treatments upregulated the hepatic mRNA expression for somatotropic axis genes (GHR, GHR1A, IGF1, IGFBP3, and SOCS2) on d -7 relative to calving and upregulated the mRNA expression for SOCS2 on d 7. On d -7, rbST87.5 and rbST125 treatments increased mRNA expression for genes involved in hepatic lipid transport (ANGPTL4, APOA5, APOB100, and SCARB1) and downregulated mRNA expression for PPARD, which is involved in lipid storage. On d 7, rbST tended to upregulate the mRNA expression for genes involved in gluconeogenesis (PCK1) and fatty acid β-oxidation (ACOX1), and downregulated the mRNA expression for genes involved in inflammation (TNFRSF1A, ICAM1, CXCL1, MYD88, HIF1A, IL1RN, NFKBIA, and SOCS3) and oxidative stress (XBP1). Administration of rbST during the periparturient period may improve liver function and health by increasing hepatic capacity for gluconeogenesis and lipid transport and by reducing inflammation and oxidative stress., (Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)
- Published
- 2017
- Full Text
- View/download PDF
45. Charge-Induced Force Noise on Free-Falling Test Masses: Results from LISA Pathfinder.
- Author
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Armano M, Audley H, Auger G, Baird JT, Binetruy P, Born M, Bortoluzzi D, Brandt N, Bursi A, Caleno M, Cavalleri A, Cesarini A, Cruise M, Danzmann K, de Deus Silva M, Diepholz I, Dolesi R, Dunbar N, Ferraioli L, Ferroni V, Fitzsimons ED, Flatscher R, Freschi M, Gallegos J, García Marirrodriga C, Gerndt R, Gesa L, Gibert F, Giardini D, Giusteri R, Grimani C, Grzymisch J, Harrison I, Heinzel G, Hewitson M, Hollington D, Hueller M, Huesler J, Inchauspé H, Jennrich O, Jetzer P, Johlander B, Karnesis N, Kaune B, Killow CJ, Korsakova N, Lloro I, Liu L, López-Zaragoza JP, Maarschalkerweerd R, Madden S, Mance D, Martín V, Martin-Polo L, Martino J, Martin-Porqueras F, Mateos I, McNamara PW, Mendes J, Mendes L, Moroni A, Nofrarias M, Paczkowski S, Perreur-Lloyd M, Petiteau A, Pivato P, Plagnol E, Prat P, Ragnit U, Ramos-Castro J, Reiche J, Romera Perez JA, Robertson DI, Rozemeijer H, Rivas F, Russano G, Sarra P, Schleicher A, Slutsky J, Sopuerta C, Sumner TJ, Texier D, Thorpe JI, Trenkel C, Vetrugno D, Vitale S, Wanner G, Ward H, Wass PJ, Wealthy D, Weber WJ, Wittchen A, Zanoni C, Ziegler T, and Zweifel P
- Abstract
We report on electrostatic measurements made on board the European Space Agency mission LISA Pathfinder. Detailed measurements of the charge-induced electrostatic forces exerted on free-falling test masses (TMs) inside the capacitive gravitational reference sensor are the first made in a relevant environment for a space-based gravitational wave detector. Employing a combination of charge control and electric-field compensation, we show that the level of charge-induced acceleration noise on a single TM can be maintained at a level close to 1.0 fm s^{-2} Hz^{-1/2} across the 0.1-100 mHz frequency band that is crucial to an observatory such as the Laser Interferometer Space Antenna (LISA). Using dedicated measurements that detect these effects in the differential acceleration between the two test masses, we resolve the stochastic nature of the TM charge buildup due to interplanetary cosmic rays and the TM charge-to-force coupling through stray electric fields in the sensor. All our measurements are in good agreement with predictions based on a relatively simple electrostatic model of the LISA Pathfinder instrument.
- Published
- 2017
- Full Text
- View/download PDF
46. Strain effects on oxygen vacancy energetics in KTaO 3 .
- Author
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Xi J, Xu H, Zhang Y, and Weber WJ
- Abstract
Due to lattice mismatch between epitaxial films and substrates, in-plane strain fields are produced in the thin films, with accompanying structural distortions, and ion implantation can be used to controllably engineer the strain throughout the film. Because of the strain profile, local defect energetics are changed. In this study, the effects of in-plane strain fields on the formation and migration of oxygen vacancies in KTaO
3 are investigated using first-principles calculations. In particular, the doubly positive charged oxygen vacancy (V) is studied, which is considered to be the main charge state of the oxygen vacancy in KTaO3 . We find that the formation energies for oxygen vacancies are sensitive to in-plane strain and oxygen position. The local atomic configuration is identified, and strong relaxation of local defect structure is mainly responsible for the formation characteristics of these oxygen vacancies. Based on the computational results, formation-dependent site preferences for oxygen vacancies are expected to occur under epitaxial strain, which can result in orders of magnitude differences in equilibrium vacancy concentrations on different oxygen sites. In addition, all possible migration pathways, including intra- and inter-plane diffusions, are considered. In contrast to the strain-enhanced intra-plane diffusion, the diffusion in the direction normal to the strained plane is impeded under the epitaxial strain field. These anisotropic diffusion processes can further enhance site preferences.- Published
- 2017
- Full Text
- View/download PDF
47. Enhancing radiation tolerance by controlling defect mobility and migration pathways in multicomponent single-phase alloys.
- Author
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Lu C, Niu L, Chen N, Jin K, Yang T, Xiu P, Zhang Y, Gao F, Bei H, Shi S, He MR, Robertson IM, Weber WJ, and Wang L
- Abstract
A grand challenge in material science is to understand the correlation between intrinsic properties and defect dynamics. Radiation tolerant materials are in great demand for safe operation and advancement of nuclear and aerospace systems. Unlike traditional approaches that rely on microstructural and nanoscale features to mitigate radiation damage, this study demonstrates enhancement of radiation tolerance with the suppression of void formation by two orders magnitude at elevated temperatures in equiatomic single-phase concentrated solid solution alloys, and more importantly, reveals its controlling mechanism through a detailed analysis of the depth distribution of defect clusters and an atomistic computer simulation. The enhanced swelling resistance is attributed to the tailored interstitial defect cluster motion in the alloys from a long-range one-dimensional mode to a short-range three-dimensional mode, which leads to enhanced point defect recombination. The results suggest design criteria for next generation radiation tolerant structural alloys.
- Published
- 2016
- Full Text
- View/download PDF
48. Evidence-Based Evaluation of Complementary Health Approaches for Pain Management in the United States.
- Author
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Nahin RL, Boineau R, Khalsa PS, Stussman BJ, and Weber WJ
- Subjects
- Acupuncture Therapy, Humans, Massage, United States, Back Pain therapy, Chronic Pain therapy, Complementary Therapies methods, Evidence-Based Medicine methods, Neck Pain therapy, Pain Management methods
- Abstract
Although most pain is acute and resolves within a few days or weeks, millions of Americans have persistent or recurring pain that may become chronic and debilitating. Medications may provide only partial relief from this chronic pain and can be associated with unwanted effects. As a result, many individuals turn to complementary health approaches as part of their pain management strategy. This article examines the clinical trial evidence for the efficacy and safety of several specific approaches-acupuncture, manipulation, massage therapy, relaxation techniques including meditation, selected natural product supplements (chondroitin, glucosamine, methylsulfonylmethane, S-adenosylmethionine), tai chi, and yoga-as used to manage chronic pain and related disability associated with back pain, fibromyalgia, osteoarthritis, neck pain, and severe headaches or migraines., (Copyright © 2016 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.)
- Published
- 2016
- Full Text
- View/download PDF
49. Color-center production and recovery in electron-irradiated magnesium aluminate spinel and ceria.
- Author
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Costantini JM, Lelong G, Guillaumet M, Weber WJ, Takaki S, and Yasuda K
- Abstract
Single crystals of magnesium aluminate spinel (MgAl2O4) with (1 0 0) or (1 1 0) orientations and cerium dioxide or ceria (CeO2) were irradiated by 1.0 MeV and 2.5 MeV electrons in a high-fluence range. Point-defect production was studied by off-line UV-visible optical spectroscopy after irradiation. For spinel, regardless of both crystal orientation and electron energy, two characteristic broad bands centered at photon energies of 5.4 eV and 4.9 eV were assigned to F and F(+) centers (neutral and singly ionized oxygen vacancies), respectively, on the basis of available literature data. No clear differences in color-center formation were observed for the two crystal orientations. Using calculations from displacement cross sections by elastic collisions, these results are consistent with a very large threshold displacement energy (200 eV) for oxygen atoms at room temperature. A third very broad band centered at 3.7 eV might be attributed either to an oxygen hole center (V-type center) or an F2 dimer center (oxygen di-vacancy). The onset of recovery of these color centers took place at 200 °C with almost full bleaching at 600 °C. Activation energies (~0.3-0.4 eV) for defect recovery were deduced from the isochronal annealing data by using a first-order kinetics analysis. For ceria, a sub-band-gap absorption feature, which peaked at ~3.1 eV, was recorded for 2.5 MeV electron irradiation only. Assuming a ballistic process, we suggest that the latter defect might result from cerium atom displacement on the basis of computed cross sections.
- Published
- 2016
- Full Text
- View/download PDF
50. Sub-Femto-g Free Fall for Space-Based Gravitational Wave Observatories: LISA Pathfinder Results.
- Author
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Armano M, Audley H, Auger G, Baird JT, Bassan M, Binetruy P, Born M, Bortoluzzi D, Brandt N, Caleno M, Carbone L, Cavalleri A, Cesarini A, Ciani G, Congedo G, Cruise AM, Danzmann K, de Deus Silva M, De Rosa R, Diaz-Aguiló M, Di Fiore L, Diepholz I, Dixon G, Dolesi R, Dunbar N, Ferraioli L, Ferroni V, Fichter W, Fitzsimons ED, Flatscher R, Freschi M, García Marín AF, García Marirrodriga C, Gerndt R, Gesa L, Gibert F, Giardini D, Giusteri R, Guzmán F, Grado A, Grimani C, Grynagier A, Grzymisch J, Harrison I, Heinzel G, Hewitson M, Hollington D, Hoyland D, Hueller M, Inchauspé H, Jennrich O, Jetzer P, Johann U, Johlander B, Karnesis N, Kaune B, Korsakova N, Killow CJ, Lobo JA, Lloro I, Liu L, López-Zaragoza JP, Maarschalkerweerd R, Mance D, Martín V, Martin-Polo L, Martino J, Martin-Porqueras F, Madden S, Mateos I, McNamara PW, Mendes J, Mendes L, Monsky A, Nicolodi D, Nofrarias M, Paczkowski S, Perreur-Lloyd M, Petiteau A, Pivato P, Plagnol E, Prat P, Ragnit U, Raïs B, Ramos-Castro J, Reiche J, Robertson DI, Rozemeijer H, Rivas F, Russano G, Sanjuán J, Sarra P, Schleicher A, Shaul D, Slutsky J, Sopuerta CF, Stanga R, Steier F, Sumner T, Texier D, Thorpe JI, Trenkel C, Tröbs M, Tu HB, Vetrugno D, Vitale S, Wand V, Wanner G, Ward H, Warren C, Wass PJ, Wealthy D, Weber WJ, Wissel L, Wittchen A, Zambotti A, Zanoni C, Ziegler T, and Zweifel P
- Abstract
We report the first results of the LISA Pathfinder in-flight experiment. The results demonstrate that two free-falling reference test masses, such as those needed for a space-based gravitational wave observatory like LISA, can be put in free fall with a relative acceleration noise with a square root of the power spectral density of 5.2±0.1 fm s^{-2}/sqrt[Hz], or (0.54±0.01)×10^{-15} g/sqrt[Hz], with g the standard gravity, for frequencies between 0.7 and 20 mHz. This value is lower than the LISA Pathfinder requirement by more than a factor 5 and within a factor 1.25 of the requirement for the LISA mission, and is compatible with Brownian noise from viscous damping due to the residual gas surrounding the test masses. Above 60 mHz the acceleration noise is dominated by interferometer displacement readout noise at a level of (34.8±0.3) fm/sqrt[Hz], about 2 orders of magnitude better than requirements. At f≤0.5 mHz we observe a low-frequency tail that stays below 12 fm s^{-2}/sqrt[Hz] down to 0.1 mHz. This performance would allow for a space-based gravitational wave observatory with a sensitivity close to what was originally foreseen for LISA.
- Published
- 2016
- Full Text
- View/download PDF
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