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1

Isoscalar E0, E1, and E2 strength in Ca-40  

E-print Network

The giant resonance region from 10 particles at small angles including 0 degrees. Strength corresponding to 97 +/- 11%, 108 +/- 12%, and 62 + 10-20 % of the isoscalar E0, E2, and E1 sum rules, respectively, was identified with centroids of 19...

Youngblood, David H.; Lui, YW; Clark, HL.

2001-01-01

2

Identification of mixed-symmetry one- and two-phonon states in 94Mo  

NASA Astrophysics Data System (ADS)

?-spectroscopy of low-lying low-spin states of the near-spherical nucleus 94Mo is reported. Photon scattering experiments and ??-coincidence measurements of ?-radiation following the ?-decay of 94Tc nuclei produced in the 94Mo(p,n) reaction and following the 91Zr(?,n)94Mo reaction were performed. We measured level energies, spin and parity quantum numbers, branching ratios, multipole mixing ratios, and lifetimes for low-spin states, which are high above yrast. The mixed-symmetry (MS)2+ one-quadrupole phonon excitation and the (MS)1+ and 3+ two-phonon states are identified from measured M1 and E2 transition strengths. We observed ?-transitions between MS states and the E2/M1 multipole mixing ratios of the F-vector 1+?21+,22+ transitions were measured. The data support the two-phonon character of the 1+MS state.

Pietralla, N.; Fransen, C.; von Brentano, P.; Kneissl, U.; Pitz, H. H.

2000-07-01

3

Energy distribution of the E1-transition strengths in the 46Ti nucleus  

NASA Astrophysics Data System (ADS)

The structure of levels of the 46Ti nucleus is studied by means of the nonselective reaction 45Sc( p, ?) at proton energies ranging between 1.2 and 3.1 MeV. Spin-parity assignments for 46Ti states of excitation energies up to 5.5 MeV are obtained by using the method of averaged resonances. Radiative strength functions for E1 transitions populating these states are determined. The resulting data are compared with predictions of various models.

Fedorets, I. D.; Ratkevich, S. S.

2008-08-01

4

First experimental evidence for two-phonon octupole-?-vibrational excitations in deformed nuclei  

NASA Astrophysics Data System (ADS)

Systematic nuclear resonance fluorescence experiments, including model independent parity determinations, provided evidence for enhanced E1 excitations near 2.5 MeV excitation energy in the deformed nuclei 150Nd, 160Gd, and 162,164Dy. The corresponding J?=1- states are interpreted as two-phonon excitations due to the coupling of octupole (J=3-,K=1) and quadrupole ? vibrations (J=2+,K=2). The results can be explained in the framework of the sdf interacting-boson-approximation model and the dynamic collective model describing octupole vibrations and their coupling to quadrupole vibrations in deformed nuclei.

Kneissl, U.; Zilges, A.; Margraf, J.; Bauske, I.; von Brentano, P.; Friedrichs, H.; Heil, R. D.; Herzberg, R.-D.; Pitz, H. H.; Schlitt, B.; Wesselborg, C.

1993-10-01

5

New probe of M1 and E1 strengths in GDR regions  

NASA Astrophysics Data System (ADS)

The M1 strengths (or level density of 1+ states) are of importance for estimation of interaction strengths between neutrinos and nuclei for the study of the supernova neutrino-process. In 1957, Agodi predicted theoretically angular distribution of neutrons emitted from states excited via dipole transitions with linearly polarized gamma-ray beam at the polar angle of ?=90° should be followed by a simple function, a + b cos(2?), where ?, is azimuthal angel. However, this theoretical prediction has not been verified over the wide mass region except for light nuclei as deuteron. We have measured neutron angular distributions with (polarized gamma, n) reactions on Au, Nal, and Cu. We have verified the Agodi's prediction for the first time over the wide mass region. This suggests that (polarized gamma, n) reactions may be useful tools to study M1 strengths in giant resonance regions.

Hayakawa, T.; Ogata, K.; Miyamoto, S.; Mochizuki, T.; Horikawa, K.; Amano, S.; Imazaki, K.; Li, D.; Izawa, Y.; Chiba, S.

2014-05-01

6

New probe of M1 and E1 strengths in GDR regions  

SciTech Connect

The M1 strengths (or level density of 1{sup +} states) are of importance for estimation of interaction strengths between neutrinos and nuclei for the study of the supernova neutrino-process. In 1957, Agodi predicted theoretically angular distribution of neutrons emitted from states excited via dipole transitions with linearly polarized gamma-ray beam at the polar angle of ?=90° should be followed by a simple function, a + b cos(2?), where ?, is azimuthal angel. However, this theoretical prediction has not been verified over the wide mass region except for light nuclei as deuteron. We have measured neutron angular distributions with (polarized gamma, n) reactions on Au, Nal, and Cu. We have verified the Agodi's prediction for the first time over the wide mass region. This suggests that (polarized gamma, n) reactions may be useful tools to study M1 strengths in giant resonance regions.

Hayakawa, T. [Japan Atomic Energy Agency and National Astronomical Observatory in Japan (Japan); Ogata, K. [RCNP, Osaka University (Japan); Miyamoto, S.; Mochizuki, T.; Horikawa, K.; Amano, S. [University of Hyogo (Japan); Imazaki, K.; Li, D.; Izawa, Y. [Institute for Laser Technology (Japan); Chiba, S. [Tokyo Institute of Technology (Japan)

2014-05-02

7

Stokes suppression and supercontinuum generation by differential two-phonon excitation.  

PubMed

Stimulated Raman scattering driven by differential coupling of two phonon modes has been demonstrated. These phonon modes are coherently and strongly coupled by external fields via two-phonon excitation at the first Brillouin zone boundary. Up to 11th order of sidebands and a supercontinuum covering entire visible region have been observed. The original Stokes and anti-Stokes lines by the single-phonon stimulated Raman scattering were significantly suppressed. PMID:25401797

Nishioka, Hajime

2014-11-01

8

Fast two-phonon relaxation process between the Landau levels of graphene on different polar substrates  

NASA Astrophysics Data System (ADS)

Within the frame of Huang-Rhys's lattice relaxation model, we theoretically investigate the carrier relaxation mediated by two-phonon processes, which consists in polar surface optical phonon and longitudinal acoustic phonon emission between the Landau levels of graphene on different polar substrates. This two-phonon relaxation process is very fast within the picosecond scale and may seriously hinder the carrier multiplication based on effective Auger processes. Moreover, the polarizability of the polar substrate plays an important role in determining the relaxation time. These results could be helpful in designing graphene-based photoelectric and photodetector devices.

Wang, Zi-Wu; Liu, Lei; Li, Zhi-Qing

2014-11-01

9

Electromagnetically induced transparency from two-phonon processes in quadratically coupled membranes  

SciTech Connect

We describe how electromagnetically induced transparency can arise in quadratically coupled optomechanical systems. Due to quadratic coupling, the underlying optical process involves a two-phonon process in an optomechanical system, and this two-phonon process makes the mean displacement, which plays the role of atomic coherence in traditional electromagnetically induced transparency (EIT), zero. We show how the fluctuation in displacement can play a role similar to atomic coherence and can lead to EIT-like effects in quadratically coupled optomechanical systems. We show how such effects can be studied using the existing optomechanical systems.

Huang, Sumei; Agarwal, G. S. [Department of Physics, Oklahoma State University, Stillwater, Oklahoma 74078 (United States)

2011-02-15

10

Changes in rotational characters of one- and two-phonon $?$-vibrational bands in $^{105}$Mo  

E-print Network

The $\\gamma$ vibration is the most typical low-lying collective motion prevailing the nuclear chart. But only few one-phonon rotational bands in odd-$A$ nuclei have been known. Furthermore, two-phonon states, even the band head, have been observed in a very limited number of nuclides not only of odd-$A$ but even-even. Among them, that in $^{105}$Mo is unique in that Coriolis effects are expected to be stronger than in $^{103}$Nb and $^{105}$Nb on which theoretical studies were reported. Then the purpose of the present work is to study $^{105}$Mo paying attention to rotational character change of the one-phonon and two-phonon bands. The particle-vibration coupling model based on the cranking model and the random-phase approximation is used to calculate the vibrational states in rotating odd-$A$ nuclei. The present model reproduces the observed yrast zero-phonon and one-phonon bands well. Emerging general features of the rotational character change from low spin to high spin are elucidated. In particular, the reason why the one-phonon band does not exhibit signature splitting is clarified. The calculated collectivity of the two-phonon states, however, is located higher than observed.

Masayuki Matsuzaki

2014-10-21

11

Radiative lifetimes and band oscillator strengths for metal oxides. II - SiO E 1 Sigma /+/-X 1 Sigma /+/  

NASA Technical Reports Server (NTRS)

Use of an electron-beam phase-shift apparatus to obtain the radiative lifetimes for vibrational levels of the SiO E 1 Sigma (+) state. It is found that the radiative lifetimes for the vibrational transitions of the E-X band are independent of the vibrational upper state. The measured phase shifts yield cascade free lifetimes of 10.5 plus or minus 1.1 nsec for v' from 1 to 7. Spectroscopic data from Elander and Lagerqvist (1971) were used to calculate potential curves by the Klein-Dunham procedure, and Franck-Condon factors and r-centroids for the transition were computed.

Elander, N.; Smith, W. H.

1973-01-01

12

Analysis of two-phonon infrared spectral features of gallium arsenide and indium phosphide by first-principles calculations  

NASA Astrophysics Data System (ADS)

We perform a self-consistent calculation based on density functional perturbation theory to analyze the infrared spectral features of GaAs and InP arising from two-phonon processes. The features are identified and assigned the critical points in the first Brillouin zone. Distribution of the critical points is investigated. The analysis demonstrates that collections of phonons of wave vectors around symmetry points and along symmetry lines are responsible for strong infrared features in two-phonon processes.

Lin, Huang-Hsiang; Chung, Pei-Kang; Yen, Shun-Tung

2014-12-01

13

Significance of an external magnetic field on two-phonon processes in gated lateral semiconductor quantum dots  

NASA Astrophysics Data System (ADS)

Theoretical and numerical calculations of two-phonon processes on gated lateral semiconductor quantum dots (QDs) are outlined. A heterostructure made with two laterally coupled QDs, in the presence of an external magnetic field, has been employed in order to study the electron scattering rate due to two-phonon processes. The formalism is based on the acoustic phonon modes via the unscreened deformation potential and the piezoelectric interaction whenever the crystal lattice lacks a center of inversion symmetry. The rates are calculated by using second order perturbation theory. The strong dependence of the scattering rate on the external magnetic field, lattice temperature and QDs separation distance is presented.

Stavrou, V. N.; Veropoulos, G. P.

2014-08-01

14

Relaxation times of the two-phonon processes with spin-flip and spin-conserving in quantum dots  

SciTech Connect

We perform a theoretical investigation on the two-phonon processes of the spin-flip and spin-conserving relaxation in quantum dots in the frame of the Huang-Rhys' lattice relaxation model. We find that the relaxation time of the spin-flip is two orders of magnitude longer than that of the spin-conserving, which is in agreement with previous experimental measurements. Moreover, the opposite variational trends of the relaxation time as a function of the energy separation for two-phonon processes are obtained in different temperature regime. The relaxation times display the oscillatory behaviors at the demarcation point with increasing magnetic field, where the energy separation matches the optical phonon energy and results in the optical phonon resonance. These results are useful in understanding the intraband levels' relaxation in quantum dots and could be helpful in designing photoelectric and spin-memory devices.

Wang, Zi-Wu, E-mail: zwwang@semi.ac.cn [Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparing Technology, Department of Physics, Tianjin University, Tianjin 300072 (China); Liu, Lei [Suzhou Institute of Nano-Tech and Nano-Bionics, CAS, Suzhou 215125 (China); Li, Shu-Shen [Institute of Semiconductor, CAS, Beijing 100083 (China)

2014-04-07

15

Rotational character change of the one-phonon and two-phonon $\\gamma$ vibration in odd-$A$ nuclei  

E-print Network

\\item[Background] The $\\gamma$ vibration is the most typical low-lying collective motion prevailing the nuclear chart. But only few one-phonon rotational bands in odd-$A$ nuclei have been known. Furthermore, two-phonon states, even the band head, have been observed in a very limited number of nuclides not only of odd-$A$ but even-even. \\item[Purpose] Among them, that in $^{105}$Mo is unique in that Coriolis effects are expected to be stronger than in $^{103}$Nb and $^{105}$Nb on which theoretical studies were reported. Then the purpose of the present work is to study $^{105}$Mo paying attention to rotational character change of the one-phonon and two-phonon bands in comparison with the present author's previous studies on $^{103}$Nb and $^{105}$Nb. \\item[Method] The particle-vibration coupling model based on the cranking model and the random-phase approximation is used to calculate the vibrational states in rotating odd-$A$ nuclei. \\item[Results] The present model reproduces the observed yrast zero-phonon and...

Matsuzaki, Masayuki

2014-01-01

16

Two-neutrino double-beta decay to excited one- and two-phonon states  

NASA Astrophysics Data System (ADS)

The two-neutrino double-beta (2???) decay to excited final states is discussed in the framework of the quasiparticle random-phase approximation (QRPA). The excited states are assumed to have the structure of one or two QRPA phonons. The 2??? decay of 76Se and 136Ba, as well as some electromagnetic observables, are discussed as an application of the present formalism. The calculations have been performed using realistic nucleon-nucleon interaction and explicit summation over the virtual states of the intermediate nucleus. It is found that contrary to the decay to the ground state, the decay rate to the excited states is only very weakly dependent upon the strength of the particle-particle channel of the two-body interaction. This makes these decays more independent of the parametrization of the residual interaction and thus attractive in view of comparison with experimental data.

Civitarese, O.; Suhonen, J.

1994-08-01

17

Generalized two phonon theory  

Microsoft Academic Search

Recent laser experiments and theoretical discussions of coherent two photon transient phenomena have prompted us to develop a generalized theory for the case of anN+2 level quantum system interacting with two optical fields. New perturbation solutions, derived from an effective two level Hamiltonian, are presented in the form of a continued fraction expansion where the leading term agrees with earlier

Axel Schenzle; Richard G. Brewer

1978-01-01

18

Oscillator Strengths and Predissociation Rates for Rydberg Transitions in 12C16O, 13C16O, and 13C18O Involving the E 1?, B 1?+, and W 1? States  

NASA Astrophysics Data System (ADS)

One of the processes controlling the interstellar CO abundance and the ratio of its isotopologues is photodissociation. Accurate oscillator strengths and predissociation rates for Rydberg transitions are needed for modeling this process. We present results on absorption from the E 1?-X 1?+ (1-0) and B 1?+-X 1?+ (6-0) bands at 1051 and 1002 Å, respectively, and the vibrational progression W 1?-X 1?+ (v'-0) bands with v'=0-3 at 972, 956, 941, and 925 Å, respectively. The corresponding spectra were acquired at the high resolution (R~30,000) SU5 beam line at the Super ACO Synchrotron in Orsay, France. Spectra were obtained for the 12C16O, 13C 16O, and 13C18O isotopologues. These represent the most complete set of measurements available. Comparison is made with earlier results, both empirical and theoretical. While earlier determinations of oscillator strengths based on absorption from synchrotron radiation tend to be somewhat smaller than ours, the suite of measurements from a variety of techniques agree for the most part, considering the mutual uncertainties. For the bands studied here, their relative weakness, or their significant line widths arising from predissociation, minimizes potential problems from large optical depths at line center in absorption measurements. Predissociating line widths could generally be extracted from the spectra thanks to the profile simulations used in the analysis. In many cases, these simulations allowed us to consider e and f parity levels separately and to determine the dependence of the width on rotational quantum number, J. Our results are consistent with earlier determinations, especially the widths inferred from laser experiments.

Eidelsberg, M.; Sheffer, Y.; Federman, S. R.; Lemaire, J. L.; Fillion, J. H.; Rostas, F.; Ruiz, J.

2006-08-01

19

Generation of Coherent Phonons in a CdTe Single Crystal Using an Ultrafast Two-Phonon Laser-Excitation Process  

NASA Astrophysics Data System (ADS)

The detection-energy dependence of a coherent phonon in a (001) CdTe crystal, generated by ultrashort laser pulses with the center energy transparent or opaque to the sample, is investigated using a spectrally resolved pump-probe method. At the excitation in the transparent region, the detection-energy dependence of the phonon amplitude has two peaks at the energy shifted by one times the phonon energy of CdTe from the center energy of the probe pulses. On the other hand, the amplitude in the opaque region shows two peaks at the energy shifted by about two times the phonon energy. This difference occurs even though the observed energies of the coherent phonons in both regions are the same as that of the longitudinal optical phonon of CdTe. The energy shifts in the detection-energy dependence imply that the emission and absorption of one phonon and two phonons in the transparent and opaque regions, respectively, are implicated in coherent phonon generation. In this study, the detection-energy dependence is examined from the viewpoint of the third-order nonlinear susceptibility based on the impulsive stimulated Raman scattering process under nonresonant and resonant conditions.

Mizoguchi, K.; Morishita, R.; Oohata, G.

2013-02-01

20

Generation of coherent phonons in a CdTe single crystal using an ultrafast two-phonon laser-excitation process.  

PubMed

The detection-energy dependence of a coherent phonon in a (001) CdTe crystal, generated by ultrashort laser pulses with the center energy transparent or opaque to the sample, is investigated using a spectrally resolved pump-probe method. At the excitation in the transparent region, the detection-energy dependence of the phonon amplitude has two peaks at the energy shifted by one times the phonon energy of CdTe from the center energy of the probe pulses. On the other hand, the amplitude in the opaque region shows two peaks at the energy shifted by about two times the phonon energy. This difference occurs even though the observed energies of the coherent phonons in both regions are the same as that of the longitudinal optical phonon of CdTe. The energy shifts in the detection-energy dependence imply that the emission and absorption of one phonon and two phonons in the transparent and opaque regions, respectively, are implicated in coherent phonon generation. In this study, the detection-energy dependence is examined from the viewpoint of the third-order nonlinear susceptibility based on the impulsive stimulated Raman scattering process under nonresonant and resonant conditions. PMID:25166406

Mizoguchi, K; Morishita, R; Oohata, G

2013-02-15

21

Shear Strength  

NSDL National Science Digital Library

Dr. John Atkinson, of the University of the West of England, developed a site for undergraduate students wanting to learn more about soil classification. His site addresses issues such as: shear strength, peak strength, and residual strength testing. Filled with charts, diagrams, statistics, the information is pertinent and easily understood by almost any audience.

Atkinson, John

2008-10-07

22

Strength Testing.  

ERIC Educational Resources Information Center

Postural deviations resulting from strength and flexibility imbalances include swayback, scoliosis, and rounded shoulders. Screening tests are one method for identifying strength problems. Tests for the evaluation of postural problems are described, and exercises are presented for the strengthening of muscles. (JN)

Londeree, Ben R.

1981-01-01

23

Transitional ? strength in Cd isotopes  

NASA Astrophysics Data System (ADS)

The level densities and ?-ray strength functions of 105,106,111,112Cd have been extracted from particle-? coincidence data using the Oslo method. The level densities are in very good agreement with known levels at low excitation energy. The ?-ray strength functions display no strong enhancement for low ? energies. However, more low-energy strength is apparent for 105,106Cd than for 111,112Cd. For ? energies above ?4 MeV, there is evidence for some extra strength, similar to what has been previously observed for the Sn isotopes. The origin of this extra strength is unclear; it might be due to E1 and M1 transitions originating from neutron skin oscillations or the spin-flip resonance, respectively.

Larsen, A. C.; Ruud, I. E.; Bürger, A.; Goriely, S.; Guttormsen, M.; Görgen, A.; Hagen, T. W.; Harissopulos, S.; Nyhus, H. T.; Renstrøm, T.; Schiller, A.; Siem, S.; Tveten, G. M.; Voinov, A.; Wiedeking, M.

2013-01-01

24

26 CFR 1.367(e)-1 - Distributions described in section 367(e)(1).  

Code of Federal Regulations, 2010 CFR

...Revenue 4 2010-04-01 2010-04-01 false Distributions described in section 367(e)(1). 1.367(e)-1 Section 1.367(e)-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED)...

2010-04-01

25

Gene coding for the E1 endoglucanase  

DOEpatents

The gene encoding Acidothermus cellulolyticus E1 endoglucanase is cloned and expressed in heterologous microorganisms. A new modified E1 endoglucanase enzyme is produced along with variants of the gene and enzyme. The E1 endoglucanase is useful for hydrolyzing cellulose to sugars for simultaneous or later fermentation into alcohol. 6 figs.

Thomas, S.R.; Laymon, R.A.; Himmel, M.E.

1996-07-16

26

Gene coding for the E1 endoglucanase  

DOEpatents

The gene encoding Acidothermus cellulolyticus E1 endoglucanase is cloned and expressed in heterologous microorganisms. A new modified E1 endoglucanase enzyme is produced along with variants of the gene and enzyme. The E1 endoglucanase is useful for hydrolyzing cellulose to sugars for simultaneous or later fermentation into alcohol.

Thomas, Steven R. (Denver, CO); Laymon, Robert A. (Littleton, CO); Himmel, Michael E. (Littleton, CO)

1996-01-01

27

Strength Reduction via SSAPRE  

Microsoft Academic Search

We present techniques that allow strength reduction to be performed concurrently with partial redundancy elimination in the SSAPRE framework. By sharing the characteristics inherent to SSAPRE, the resulting strength reduction algorithm exhibits many interesting attributes. We compare various aspects of the new strength reduction algorithm with previous strength reduction algorithms. We also outline and discuss our implementation of the closely

Robert Kennedy; Fred C. Chow; Peter Dahl; Shin-ming Liu; Raymond Lo; Mark Streich

1998-01-01

28

26 CFR 1.367(e)-1 - Distributions described in section 367(e)(1).  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Distributions described in section 367(e)(1...Corporation § 1.367(e)-1 Distributions described in section 367(e)(1...corporation (distributing corporation) on a distribution of stock or securities of a...

2011-04-01

29

Flexibility and Muscular Strength.  

ERIC Educational Resources Information Center

This definition of flexibility and muscular strength also explores their roles in overall physical fitness and focuses on how increased flexibility and muscular strength can help decrease or eliminate lower back pain. (CB)

Liemohn, Wendell

1988-01-01

30

Strength Training for Girls.  

ERIC Educational Resources Information Center

Strength training can be fun, safe, and appropriate for young girls and women and is an important component of any fitness program when combined with appropriate cardiovascular and flexibility activities. Concerns and misconceptions regarding girls' strength training are discussed, presenting general principles of strength training for children…

Connaughton, Daniel; Connaughton, Angela; Poor, Linda

2001-01-01

31

Strength of Human Pulleys  

Microsoft Academic Search

The length, breaking strength, and tensile strength of each of the annular fibro-osseous pulleys of digital flexor sheath in ten fresh human cadaver specimens were measured. The first annular pulley and the fourth annular pulley were found to be the strongest, while the second annular pulley was the weakest. The design of artificial pulleys should reproduce the strength of the

PAUL R. MANSKE; PEGGY A. LESKER

1977-01-01

32

Homology Modelling of Human E1 Ubiquitin Activating Enzyme  

PubMed Central

Human E1 is a key player in protein ubiquitination, however the E1 structure is not available. In this paper, we describe the derivation of a human E1 structure using molecular modelling based on the crystal structure of S. cerevisiae E1 and M. Musculus E1. Key interactions between our E1 model and ubiquitin are also discussed. PMID:20396627

Brahemi, Ghali; Burger, Angelika M.; Westwell, Andrew D.; Brancale, Andrea

2010-01-01

33

Adenovirus E1B 19-kilodalton protein overcomes the cytotoxicity of E1A proteins.  

PubMed Central

Infection with adenovirus mutants carrying either point mutations or deletions in the coding region for the 19-kDa E1B gene product (19K protein) causes degradation of host cell and viral DNAs (deg phenotype) and enhanced cytopathic effect (cyt phenotype). Therefore, one function of the E1B 19K protein is to protect nuclear DNA integrity and preserve cytoplasmic architecture during productive adenovirus infection. When placed in the background of a virus incapable of expressing a functional E1A gene product, however, E1B 19K gene mutations do not result in the appearance of the cyt and deg phenotypes. This demonstrated that expression of the E1A proteins was responsible for inducing the appearance of the cyt and deg phenotypes. By constructing a panel of viruses possessing E1A mutations spanning each of the three E1A conserved regions in conjunction with E1B 19K gene mutations, we mapped the induction of the cyt and deg phenotypes to the amino-terminal region of E1A. Viruses that fail to express conserved region 3 (amino acids 140 to 185) and/or 2, (amino acids 121 to 185) or nonconserved sequences between conserved regions 2 and 1 of E1A (amino acids 86 to 120) were still capable of inducing cyt and deg. This indicated that activities associated with these regions, such as transactivation and binding to the product of the retinoblastoma susceptibility gene, were dispensable for induction of E1A-dependent cytotoxic effects. In contrast, deletion of sequences in the amino terminus of E1A (amino acids 22 to 107) resulted in extragenic suppression of the cyt and deg phenotypes. Therefore, a function affected by deletion of amino acids 22 to 86 of E1A is responsible for exerting cytotoxic effects in virally infected cells. Furthermore, transient high-level expression of the E1A region using a cytomegalovirus promoter plasmid expression vector was sufficient to induce the cyt and deg phenotypes, demonstrating that E1A expression alone is sufficient to exert these cytotoxic effects and that other viral gene products are not involved. Finally, placing E1A expression under the control of a strong promoter did not alter the requirement for E1B in the transformation of primary cells. One possibility is that the E1B 19K protein is required to overcome the cytotoxic effects of E1A protein expression and thereby enable primary cells to become transformed. Images PMID:1851867

White, E; Cipriani, R; Sabbatini, P; Denton, A

1991-01-01

34

Strength Modeling Report  

NASA Technical Reports Server (NTRS)

Strength modeling is a complex and multi-dimensional issue. There are numerous parameters to the problem of characterizing human strength, most notably: (1) position and orientation of body joints; (2) isometric versus dynamic strength; (3) effector force versus joint torque; (4) instantaneous versus steady force; (5) active force versus reactive force; (6) presence or absence of gravity; (7) body somatotype and composition; (8) body (segment) masses; (9) muscle group envolvement; (10) muscle size; (11) fatigue; and (12) practice (training) or familiarity. In surveying the available literature on strength measurement and modeling an attempt was made to examine as many of these parameters as possible. The conclusions reached at this point toward the feasibility of implementing computationally reasonable human strength models. The assessment of accuracy of any model against a specific individual, however, will probably not be possible on any realistic scale. Taken statistically, strength modeling may be an effective tool for general questions of task feasibility and strength requirements.

Badler, N. I.; Lee, P.; Wong, S.

1985-01-01

35

Alumina fiber strength improvement  

NASA Technical Reports Server (NTRS)

The effective fiber strength of alumina fibers in an aluminum composite was increased to 173,000 psi. A high temperature heat treatment, combined with a glassy carbon surface coating, was used to prevent degradation and improve fiber tensile strength. Attempts to achieve chemical strengthening of the alumina fiber by chromium oxide and boron oxide coatings proved unsuccessful. A major problem encountered on the program was the low and inconsistent strength of the Dupont Fiber FP used for the investigation.

Pepper, R. T.; Nelson, D. C.

1982-01-01

36

P a g e | 1 RECORDS MANAGEMENT  

E-print Network

P a g e | 1 RECORDS MANAGEMENT POLICY University Policy No: IM7700 Classification: Information authorities, responsibilities, and accountabilities for Records Management. DEFINITIONS 2.00 Access includes program or any other mechanism that produces records. 6.00 Records Management means the application

Pedersen, Tom

37

Time-dependent density-functional studies on strength functions in neutron-rich nuclei  

E-print Network

The electric dipole (E1) strength functions have been systematically calculated based on the time-dependent density functional theory (TDDFT), using the finite amplitude method and the real-time approach to the TDDFT with pairing correlations. The low-energy E1 strengths in neutron-rich isotopes show peculiar behaviors, such as sudden enhancement and reduction, as functions of the neutron numbers.They seem to be due to the interplay between the neutron shell effect and the deformation effect.

Shuichiro Ebata; Tsunenori Inakura; Takashi Nakatsukasa

2013-02-08

38

Genetic polymorphism in CYP2E1: Population distribution of CYP2E1 activity.  

PubMed

Cytochrome P-450 2E1 (CYP2E1) is a key enzyme in the metabolic activation of a variety of toxicants including nitrosamines, benzene, vinyl chloride, and halogenated solvents such as trichloroethylene. CYP2E1 is also one of the enzymes that metabolizes ethanol to acetaldehyde, and is induced by recent ethanol ingestion. There is evidence that interindividual variability in the expression and functional activity of this cytochrome (CYP) may be considerable. Genetic polymorphisms in CYP2E1 were identified and linked to altered susceptibility to hepatic cirrhosis induced by ethanol and esophageal and other cancers in some epidemiological studies. Therefore, it is important to evaluate how such polymorphisms affect CYP2E1 function and whether it is possible to construct a population distribution of CYP2E1 activity based upon the known effects of these polymorphisms and their frequency in the population. This analysis is part of the genetic polymorphism database project described in the lead article in this series and followed the approach described in that article (Ginsberg et al., 2009, this issue). Review of the literature found that there are a variety of CYP2E1 variant alleles but the functional significance of these variants is still unclear. Some, but not all, studies suggest that several upstream 5' flanking mutations affect gene expression and response to inducers such as ethanol or obesity. None of the coding-region variants consistently affects enzyme function. Part of the reason for conflicting evidence regarding genotype effect on phenotype may be due to the wide variety of exposures such as ethanol or dietary factors and physiological factors including body weight or diabetes that modulate CYP2E1 expression. In conclusion, evidence is too limited to support the development of a population distribution of CYP2E1 enzyme activity based upon genotypes. Health risk assessments may best rely upon data reporting interindividual variability in CYP2E1 function for input into physiologically based pharmacokinetic (PBPK) models involving CYP2E1 substrates. PMID:20183527

Neafsey, Pat; Ginsberg, Gary; Hattis, Dale; Johns, Douglas O; Guyton, Kathryn Z; Sonawane, Babasaheb

2009-01-01

39

Impact of E1 and Cre on Adenovirus Vector Amplification: Developing MDCK CAV-2-E1 and E1-Cre Transcomplementing Cell Lines  

PubMed Central

Adenovirus vectors have been extensively studied through the manipulation of viral genome. However, little attention is being paid to their producer cell-lines; cells are selected according to virus yields, neglecting the expression profile of transcomplementing gene products underlying cell performance. This work evaluates the impact of E1 (E1A and E1B) and Cre recombinase levels in the production of E1-deleted and helper-dependent canine adenovirus type 2 (CAV-2) vectors using MDCK cells. E1A and E1B gene expression and Cre activity were evaluated in different cell clones and compared with the corresponding cell productivity and susceptibility to oxidative stress injury. CAV-2 production was proportional to E1A expression (the highest levels of E1A corresponding to productivities of 3000–5000 I.P./cell), while E1B prolonged host cell viability after infection, conferring protection against apoptosis. Cre recombinase counteracted E1B anti-apoptotic properties, however viral production was maintained under high levels of Cre. Yet, Cre recombinase side effects can be reduced using cell lines with lower Cre-activities, without compromising the excision efficiency of helper vector packaging signal. These results highlight the influence of transcomplementing gene products on CAV-2 producer cell line performance, and the ability to express high levels of E1A and E1B as an important feature for cell line establishment and high adenovirus titers. PMID:23565229

Fernandes, Paulo; Santiago, Virgínia M.; Rodrigues, Ana F.; Tomás, Hélio; Kremer, Eric J.; Alves, Paula M.; Coroadinha, Ana S.

2013-01-01

40

Impact of E1 and Cre on adenovirus vector amplification: developing MDCK CAV-2-E1 and E1-Cre transcomplementing cell lines.  

PubMed

Adenovirus vectors have been extensively studied through the manipulation of viral genome. However, little attention is being paid to their producer cell-lines; cells are selected according to virus yields, neglecting the expression profile of transcomplementing gene products underlying cell performance. This work evaluates the impact of E1 (E1A and E1B) and Cre recombinase levels in the production of E1-deleted and helper-dependent canine adenovirus type 2 (CAV-2) vectors using MDCK cells. E1A and E1B gene expression and Cre activity were evaluated in different cell clones and compared with the corresponding cell productivity and susceptibility to oxidative stress injury. CAV-2 production was proportional to E1A expression (the highest levels of E1A corresponding to productivities of 3000-5000 I.P./cell), while E1B prolonged host cell viability after infection, conferring protection against apoptosis. Cre recombinase counteracted E1B anti-apoptotic properties, however viral production was maintained under high levels of Cre. Yet, Cre recombinase side effects can be reduced using cell lines with lower Cre-activities, without compromising the excision efficiency of helper vector packaging signal. These results highlight the influence of transcomplementing gene products on CAV-2 producer cell line performance, and the ability to express high levels of E1A and E1B as an important feature for cell line establishment and high adenovirus titers. PMID:23565229

Fernandes, Paulo; Santiago, Virgínia M; Rodrigues, Ana F; Tomás, Hélio; Kremer, Eric J; Alves, Paula M; Coroadinha, Ana S

2013-01-01

41

The Strength of Vulnerability  

ERIC Educational Resources Information Center

Many aspects of our work with at-risk children are spiritual by nature. A whole generation of at-risk children are crying out and asking hard questions. Although we certainly will not have all the answers, a shared experience of the very vulnerability of our human condition can turn this into a strength for us and our children. The authors propose…

Gilliam, Bobby; Franklin, John Travis

2004-01-01

42

Crew Strength Training  

NSDL National Science Digital Library

In this activity, learners will train to develop upper and lower body strength in their muscles and bones by performing body-weight squats and push-ups. Learners perform the exercises over time (week or month) and record and graph their observations. This activity simulates how astronauts must participate in strength training prior to missions in order to compensate for the weakening of muscles and bones in the reduced gravity environment of space. An embedded video on this page showcases the activity. Learners can complete this activity as part of NASA's Fit Explorer Challenge, in which learners train like astronauts, set goals, track their progress, and accumulate points to progress through Exploration Levels and earn certificates.

Center, Nasa J.

2012-06-26

43

CYP2E1 and Oxidative Liver Injury by Alcohol  

PubMed Central

Ethanol-induced oxidative stress appears to play a major role in mechanisms by which ethanol causes liver injury. Many pathways have been suggested to contribute to the ability of ethanol to induce a state of oxidative stress. One central pathway appears to be the induction of cytochrome P450 2E1 (CYP2E1) by ethanol. CYP2E1 metabolizes and activates many toxicological substrates, including ethanol, to more reactive, toxic products. Levels of CYP2E1 are elevated under a variety of physiological and pathophysiological conditions, and after acute and chronic alcohol treatment. CYP2E1 is also an effective generator of reactive oxygen species such as the superoxide anion radical and hydrogen peroxide, and in the presence of iron catalysts, produces powerful oxidants such as the hydroxyl radical. This Review Article summarizes some of the biochemical and toxicological properties of CYP2E1, and briefly describes the use of cell lines developed to constitutively express CYP2E1 in assessing the actions of CYP2E1. Possible therapeutic implications for treatment of alcoholic liver injury by inhibition of CYP2E1 or CYP2E1-dependent oxidative stress will be discussed, followed by some future directions which may help to understand the actions of CYP2E1 and its role in alcoholic liver injury. PMID:18078827

Lu, Yongke; Cederbaum, Arthur I.

2008-01-01

44

Prepubescent Strength Training. Some Considerations.  

ERIC Educational Resources Information Center

Under the careful supervision of a trained fitness professional, the benefits of prepubescent strength training (improved strength, power, muscular endurance, bone density) outweigh the risks (acute and chronic musculoskeletal injuries). (CB)

Priest, Joe W.; Holshouser, Richard S.

1987-01-01

45

Strength Training and Children's Health.  

ERIC Educational Resources Information Center

Provides an overview of the potential health benefits of strength training for children, discussing the role of strength training in preventing sports-related injuries and highlighting design considerations for such programs. The focus is on musculoskeletal adaptations to strength training that are observable in healthy children. Guidelines for…

Faigenbaum, Avery D.

2001-01-01

46

Strength of Rewelded Inconel 718  

NASA Technical Reports Server (NTRS)

Inconel 718, nickel-based alloy used extensively for high-temperature structural service, welded repeatedly without detriment to its strength. According to NASA report, tests show 12 repairs on same weld joint do not adversely affect ultimate tensile strenth, yield strength, fatigue strength, metallurgical grain structures, or ability of weld joint to respond to post weld heat treatments.

Bayless, E.; Lovoy, C. V.; Mcllwain, M. C.; Munafo, P.

1982-01-01

47

Water's Hydrogen Bond Strength  

E-print Network

Water is necessary both for the evolution of life and its continuance. It possesses particular properties that cannot be found in other materials and that are required for life-giving processes. These properties are brought about by the hydrogen bonded environment particularly evident in liquid water. Each liquid water molecule is involved in about four hydrogen bonds with strengths considerably less than covalent bonds but considerably greater than the natural thermal energy. These hydrogen bonds are roughly tetrahedrally arranged such that when strongly formed the local clustering expands, decreasing the density. Such low density structuring naturally occurs at low and supercooled temperatures and gives rise to many physical and chemical properties that evidence the particular uniqueness of liquid water. If aqueous hydrogen bonds were actually somewhat stronger then water would behave similar to a glass, whereas if they were weaker then water would be a gas and only exist as a liquid at sub-zero temperatures. The overall conclusion of this investigation is that water's hydrogen bond strength is poised centrally within a narrow window of its suitability for life.

Martin Chaplin

2007-06-10

48

[The strength of fragile].  

PubMed

Chronic disorder not only modifies the patient's health status; it affects the body relationship and its potential; it decreases its power to act, changes its relation to time, to its relatives, in shortcut it affects all dimensions of the relationship with oneself, with others, and the world. However, if we assume that a patient cannot be reduced to his/her illness but must always be treated with the respect of a person, we also understand how chronic and debilitating disease affects both freedom (or autonomy) and perfectibility (or creativity). By analyzing the different forms of freedom of the patient, this paper intends to rehabilitate the fragile own strength which is fortitude. It manifests itself in attitudes and virtues such as gentleness, patience, attention to the present, hope, power of thought. It also intends to show that it is supporting fragile and allowing them to develop their own way of acting and living as humanity became intelligent and creative. PMID:24721121

Lagrée, J

2015-02-01

49

CYP2E1 autoantibodies in liver diseases  

PubMed Central

Autoimmune reactions involving cytochrome P4502E1 (CYP2E1) are a feature of idiosyncratic liver injury induced by halogenated hydrocarbons and isoniazid, but are also detectable in about one third of the patients with advanced alcoholic liver disease (ALD) and chronic hepatitis C (CHC). In these latter the presence of anti-CYP2E1 auto-antibodies is an independent predictor of extensive necro-inflammation and fibrosis and worsens the recurrence of hepatitis following liver transplantation, indicating that CYP2E1-directed autoimmunity can contribute to hepatic injury. The molecular characterization of the antigens recognized by anti-CYP2E1 auto-antibodies in ALD and CHC has shown that the targeted conformational epitopes are located in close proximity on the molecular surface. Furthermore, these epitopes can be recognized on CYP2E1 expressed on hepatocyte plasma membranes where they can trigger antibody-mediated cytotoxicity. This does not exclude that T cell-mediated responses against CYP2E1 might also be involved in causing hepatocyte damage. CYP2E1 structural modifications by reactive metabolites and molecular mimicry represent important factors in the breaking of self-tolerance against CYP2E1 in, respectively, ALD and CHC. However, genetic or acquired interferences with the mechanisms controlling the homeostasis of the immune system are also likely to contribute. More studies are needed to better characterize the impact of anti-CYP2E1 autoimmunity in liver diseases particularly in relation to the fact that common metabolic alterations such as obesity and diabetes stimulates hepatic CYP2E1 expression. PMID:25462068

Sutti, Salvatore; Rigamonti, Cristina; Vidali, Matteo; Albano, Emanuele

2014-01-01

50

Study of gamma-ray strength functions  

SciTech Connect

The use of gamma-ray strength function systematics to calculate neutron capture cross sections and capture gamma-ray spectra is discussed. The ratio of the average capture width, GAMMA/sub ..gamma../-bar, to the average level spacing, D/sub obs/, both at the neutron separation energy, can be derived from such systematics with much less uncertainty than from separate systematics for values of GAMMA/sub ..gamma../-bar and D/sub obs/. In particular, the E1 gamma-ray strength function is defined in terms of the giant dipole resonance (GDR). The GDR line shape is modeled with the usual Lorentzian function and also with a new energy-dependent, Breit-Wigner (EDBW) function. This latter form is further parameterized in terms of two overlapping resonances, even for nuclei where photonuclear measurements do not resolve two peaks. In the mass ranges studied, such modeling is successful for all nuclei away from the N = 50 closed neutron shell. Near the N = 50 shell, a one-peak EDBW appears to be more appropriate. Examples of calculated neutron capture excitation functions and capture gamma-ray spectra using the EDBW form are given for target nuclei in the mass-90 region and also in the Ta-Au mass region. 20 figures.

Gardner, D.G.; Gardner, M.A.; Dietrich, F.S.

1980-08-07

51

Strength and Conditioning for Judo  

Microsoft Academic Search

summary For elite judo athletes and recre- ational judo athletes alike, sport- specific strength and conditioning is essential in the prevention of in- juries and for enhancing perfor- mance. This article offers sugges- tions for judo athletes and coaches for the development of strength and conditioning programs specific to the requirements of their sport.

John Amtmann; Adam Cotton

2005-01-01

52

Do You Have the Strength?  

NSDL National Science Digital Library

In this activity, students squeeze a tennis ball to demonstrate the strength of the human heart. Working in teams, they think of ways to keep the heart beating if the natural mechanism were to fail. The goal of this activity is to get students to understand the strength and resilience of the heart.

Integrated Teaching and Learning Program and Laboratory, University of Colorado at Boulder

2012-04-21

53

Resolvin E1 Regulates ADP Activation of Human Platelets  

PubMed Central

Objective Resolvin E1 (RvE1) is an eicosapentaenoic acid (EPA)-derived specialized pro-resolving mediator generated during resolution of acute inflammation. RvE1 exhibits potent organ-protective actions in vivo and acts on specific cell types including platelets. Here, we investigated the ability of RvE1 to regulate adenosine diphosphate (ADP) activation of platelets via specific receptors because RvE1 reduces platelet aggregation with certain agonists including ADP. Methods and Results RvE1 (0.1nM–100nM) incubated with platelets gave reduced ADP-stimulated P-selectin mobilization (IC50 ~1.6×10?12 M) and polymerized actin content compared to control platelets. RvE1 (1–100nM) did not stimulate or block intracellular calcium mobilization. Using a new P2Y12-?-arrestin-coupled cell system, ADP-activated P2Y12 with an EC50 of 5×10?6 M and RvE1 did not directly stimulate P2Y12 or block ADP-P2Y12 signals. In this system, another eicosanoid LTE4 (EC50 1.3×10?11 M) dose dependently activated P2Y12. When recombinant P2Y12-expressing cells were transiently transfected with an RvE1 receptor, human ChemR23 (present on human platelets), addition of RvE1 (0.1nM-10.0nM) blocked ADP signals (IC50 ~1.6×10?11 M) in P2Y12-ChemR23-expressing cells compared to mock transfections. Conclusions These results demonstrate that RvE1’s regulatory actions (i.e reducing ADP-stimulated P-selectin mobilization and actin polymerization) are hChemR23-dependent. Moreover, they document specific platelet actions of RvE1 selectively engaged with ADP-activated platelets that illuminate a new cellular mechanism and impact of omega-3 EPA that may contribute to both resolution of vascular inflammation and ADP-dependent platelet activation relevant in pathologic cardiovascular events. PMID:20702811

Fredman, Gabrielle; Van Dyke, Thomas E.; Serhan, Charles N.

2010-01-01

54

E1 strength of the subthreshold 3/2 + state in 15O studied by Coulomb excitation  

NASA Astrophysics Data System (ADS)

The radiative width of the 3/2+ state at 6.793 MeV in 15O has been experimentally determined to be ??=0.95+0.60-0.95 eV by intermediate-energy Coulomb excitation. Our result independently supports the recent studies which point to a minor contribution of this state to the astrophysical rate of the 14N(p,?)15O reaction in the CNO-cycle hydrogen burning in massive stars.

Yamada, K.; Motobayashi, T.; Akiyoshi, H.; Aoi, N.; Fülöp, Zs.; Gomi, T.; Higurashi, Y.; Imai, N.; Iwasa, N.; Iwasaki, H.; Iwata, Y.; Kobayashi, H.; Kurokawa, M.; Liu, Z.; Minemura, T.; Ozawa, S.; Sakurai, H.; Serata, M.; Shimoura, S.; Takeuchi, S.; Teranishi, T.; Yanagisawa, Y.; Yoshida, K.; Ishihara, M.

2004-01-01

55

CYP2E1 hydroxylation of aniline involves negative cooperativity.  

PubMed

CYP2E1 plays a role in the metabolic activation and elimination of aniline, yet there are conflicting reports on its mechanism of action, and hence relevance, in aniline metabolism. Based on our work with similar compounds, we hypothesized that aniline binds two CYP2E1 sites during metabolism resulting in cooperative reaction kinetics and tested this hypothesis through rigorous in vitro studies. The kinetic profile for recombinant CYP2E1 demonstrated significant negative cooperativity based on a fit of data to the Hill equation (n=0.56). Mechanistically, the data were best explained through a two-binding site cooperative model in which aniline binds with high affinity (K(s)=30 ?M) followed by a second weaker binding event (K(ss)=1100 uM) resulting in a threefold increase in the oxidation rate. Binding sites for aniline were confirmed by inhibition studies with 4-methylpyrazole. Inhibitor phenotyping experiments with human liver microsomes validated the central role for CYP2E1 in aniline hydroxylation and indicated minor roles for CYP2A6 and CYP2C9. Importantly, inhibition of minor metabolic pathways resulted in a kinetic profile for microsomal CYP2E1 that replicated the preferred mechanism and parameters observed with the recombinant enzyme. Scaled modeling of in vitro CYP2E1 metabolism of aniline to in vivo clearance, especially at low aniline levels, led to significant deviations from the traditional model based on non-cooperative, Michaelis-Menten kinetics. These findings provide a critical mechanistic perspective on the potential importance of CYP2E1 in the metabolic activation and elimination of aniline as well as the first experimental evidence of a negatively cooperative metabolic reaction catalyzed by CYP2E1. PMID:24345333

Hartman, Jessica H; Knott, Katie; Miller, Grover P

2014-02-01

56

EFFECT OF METHACRYLONITRILE ON CYTOCHROME P-450 2E1 (CYP2E1) EXPRESSION IN MALE F344 RATS  

Microsoft Academic Search

Tissue-specific induction of cytochrome P-450s (CYP) followed by increased in situ bioactivation may contribute to chemical-induced site-specific toxicity. In rats, methacrylonitrile (MAN) is metabolized by cytochrome P-450 2E1 (CYP2E1) to acetone, which is eliminated along with parent MAN in breath. Gavage administration of MAN to rats causes olfactory epithelial damage and liver enlargement. It was hypothesized that treatment of rats

Hongbing Wang; Brian Chanas; Burhan I. Ghanayem

2002-01-01

57

TOT: the association strength heuristic  

E-print Network

Three experiments were conducted to examine the effect of association strength on TOT (tip-of-the-tongue states) and recall. Two hundred nineteen undergraduate students studied pictures and names of 24 imaginary animals that were presented on a...

Choi, Hyun

2005-11-01

58

Effect of solar wind pressure pulses on the size and strength of the auroral oval  

E-print Network

Effect of solar wind pressure pulses on the size and strength of the auroral oval A. Boudouridis, E. [1] It has recently been found that solar wind dynamic pressure changes can dramatically affect solar wind dynamic pressure increases on the location, size, and intensity of the auroral oval using

Lummerzheim, Dirk

59

Weld width indicates weld strength  

NASA Technical Reports Server (NTRS)

Width of butt weld in 2219-T87 aluminum has been found to be more reliable indicator of weld strength than more traditional parameters of power input and cooling rate. Yield stress and ultimate tensile strength tend to decrease with weld size. This conclusion supports view of many professional welders who give priority to weld geometry over welding energy or cooling rate as indicator of weld quality.

Nunes, A. C. J.; Novak, H. L.; Mcllwain, M. C.

1982-01-01

60

Polymer Welding: Strength Through Entanglements  

E-print Network

Large-scale simulations of thermal welding of polymers are performed to investigate the rise of mechanical strength at the polymer-polymer interface with the welding time. The welding process is in the core of integrating polymeric elements into devices as well as in thermal induced healing of polymers; processes that require development of interfacial strength equal to that of the bulk. Our simulations show that the interfacial strength saturates at the bulk shear strength much before polymers diffuse by their radius of gyration. Along with the strength increase, the dominant failure mode changes from chain pullout at the interface to chain scission as in the bulk. Formation of sufficient entanglements across the interface, which we track using a Primitive Path Analysis is required to arrest catastrophic chain pullout at the interface. The bulk response is not fully recovered until the density of entanglements at the interface reaches the bulk value. Moreover, the increase of interfacial strength before saturation is proportional to the number of interfacial entanglements between chains from opposite sides.

Ting Ge; Flint Pierce; Dvora Perahia; Gary S. Grest; Mark O. Robbins

2012-11-29

61

DprE1, a new taxonomic marker in mycobacteria.  

PubMed

Among the species of the Mycobacterium genus, more than 50 have been recognized as human pathogens. In spite of the different diseases caused by mycobacteria, the interspecies genetic similarity ranges from 94% to 100%, and for some species, this value is higher than in other bacteria. Consequently, it is important to understand the relationships existing among mycobacterial species. In this context, the possibility to use Mycobacterium tuberculosis dprE1 gene as new phylogenetic/taxonomic marker has been explored. The dprE1 gene codes for the target of benzothiazinones, belonging to a very promising class of antitubercular drugs. Mutations in cysteine 387 of DprE1 are responsible for benzothiazinone resistance. The DprE1 tree, obtained with 73 amino acid sequences of mycobacterial species, revealed that concerning the benzothiazinone sensitivity/resistance, it is possible to discriminate two clusters. To validate it, a concatamer obtained from the amino acid sequences of nine mycobacterial housekeeping genes was performed. The concatamer revealed that there is no separation between the benzothiazinone-susceptible and benzothiazinone-resistant species; consequently, this parameter is not linked to the phylogeny. DprE1 tree might represent a good taxonomic marker for the assignment of a mycobacterial isolate to a species. Moreover, the concatamer represents a good reference phylogeny for the Mycobacterium genus. PMID:24024613

Incandela, Maria Loreto; Perrin, Elena; Fondi, Marco; de Jesus Lopes Ribeiro, Ana Luisa; Mori, Giorgia; Moiana, Alessia; Gramegna, Maurizio; Fani, Renato; Riccardi, Giovanna; Pasca, Maria Rosalia

2013-11-01

62

Observation of large scissors resonance strength in actinides.  

PubMed

The orbital M1 scissors resonance has been measured for the first time in the quasicontinuum of actinides. Particle-? coincidences are recorded with deuteron and (3)He-induced reactions on (232)Th. The residual nuclei (231,232,233)Th and (232,233) Pa show an unexpectedly strong integrated strength of B(M1)=11-15?(n)(2) in the E(?)=1.0-3.5 MeV region. The increased ?-decay probability in actinides due to scissors resonance is important for cross-section calculations for future fuel cycles of fast nuclear reactors and may also have an impact on stellar nucleosynthesis. PMID:23215072

Guttormsen, M; Bernstein, L A; Bürger, A; Görgen, A; Gunsing, F; Hagen, T W; Larsen, A C; Renstrøm, T; Siem, S; Wiedeking, M; Wilson, J N

2012-10-19

63

Acetaldehyde and parkinsonism: role of CYP450 2E1  

PubMed Central

The present review update the relationship between acetaldehyde (ACE) and parkinsonism with a specific focus on the role of P450 system and CYP 2E1 isozyme particularly. We have indicated that ACE is able to enhance the parkinsonism induced in mice by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, a neurotoxin able to damage the nigrostriatal dopaminergic pathway. Similarly diethyldithiocarbamate, the main metabolite of disulfiram, a drug widely used to control alcoholism, diallylsulfide (DAS) and phenylisothiocyanate also markedly enhance the toxin-related parkinsonism. All these compounds are substrate/inhibitors of CYP450 2E1 isozyme. The presence of CYP 2E1 has been detected in the dopamine (DA) neurons of rodent Substantia Nigra (SN), but a precise function of the enzyme has not been elucidated yet. By treating CYP 2E1 knockout (KO) mice with the neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, the SN induced lesion was significantly reduced when compared with the lesion observed in wild-type animals. Several in vivo and in vitro studies led to the conclusion that CYP 2E1 may enhance the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine toxicity in mice by increasing free radical production inside the dopaminergic neurons. ACE is a good substrate for CYP 2E1 enzyme as the other substrate-inhibitors and by this way may facilitate the susceptibility of dopaminergic neurons to toxic events. The literature suggests that ethanol and/or disulfiram may be responsible for toxic parkinsonism in human and it indicates that basal ganglia are the major targets of disulfiram toxicity. A very recent study reports that there are a decreased methylation of the CYP 2E1 gene and increased expression of CYP 2E1 mRNA in Parkinson's disease (PD) patient brains. This study suggests that epigenetic variants of this cytochrome contribute to the susceptibility, thus confirming multiples lines of evidence which indicate a link between environmental toxins and PD. PMID:23801948

Vaglini, Francesca; Viaggi, Cristina; Piro, Valentina; Pardini, Carla; Gerace, Claudio; Scarselli, Marco; Corsini, Giovanni Umberto

2013-01-01

64

Mean-field analysis of ground-state and low-lying electric dipole strength in C22  

NASA Astrophysics Data System (ADS)

Properties of neutron-rich C22 are studied using the mean-field approach with Skyrme energy density functionals. Its weak binding and large total reaction cross section, which are suggested by recent experiments, are simulated by modifying the central part of Skyrme potential. Calculating E1 strength distribution by using the random-phase approximation, we investigate developments of low-lying electric dipole (E1) strength and the contribution of core excitations of C20. As the neutron Fermi level approaches the zero-energy threshold (?F?-1 MeV), we find that the low-lying E1 strength exceeds the energy-weighted cluster sum rule, which indicates the importance of core excitations with the 1d5/2 orbit.

Inakura, T.; Horiuchi, W.; Suzuki, Y.; Nakatsukasa, T.

2014-06-01

65

The Adenovirus E1A Proteins Induce Apoptosis, which is Inhibited by the E1B 19-kDa and Bcl2 Proteins  

Microsoft Academic Search

Cooperation between the adenovirus E1A and E1B oncogenes is required for transformation of primary quiescent rodent cells. Although expression of E1A alone will stimulate cell proliferation sufficient to initiate transformed focus formation, proliferation fails to be sustained and foci degenerate. Coexpression of either the 19-kDa or 55-kDa E1B oncoproteins with E1A permits high-frequency transformation by overcoming this cytotoxic response. Without

Lakshmi Rao; Michael Debbas; Peter Sabbatini; David Hockenbery; Stanley Korsmeyer; Eileen White

1992-01-01

66

SOME RELATIONSHIPS OF ISOMETRIC STRENGTH, ISOTONIC STRENGTH, AND ANTHROPOMETRIC MEASURES  

Microsoft Academic Search

The purpose of this study was to investigate the relationship between isometric strength scores, the ability to lift weights before and after a weight training programme, and selected anthropometric measurements in untrained men. The subjects significantly increased the amount of weight they could handle in the training exercises, but there was no accompanying increase in the isometric tension they could

PHILIP J. RASCH; WILLIAM R. PIEKSOX

1963-01-01

67

Multi-Laboratory Validation of Estrone (E1) ELISA Methods  

EPA Science Inventory

This project is a round-robin evaluation of commercially available Enzyme-Linked Immunosorbent Assay (ELISA) technology to quantitatively or qualitatively measure the hormone estrone (E1) in combined animal feeding operation (CAFO) receiving streams. ELISA is meant to be a simpl...

68

EXPRESSION OF ENDOGLUCANASE E1 IN TRANSGENIC DUCKWEED LEMNA MINOR  

Technology Transfer Automated Retrieval System (TEKTRAN)

Transgenic duckweed (Lemna minor) that expresses Acidothermus cellulolyticus E1 endoglucanase was generated using Agrobacterium-mediated transformation. Out of 15 independent transgenic lines, 1 line with the highest CMC-degrading activity was selected for further studies. The 2-week-old transgeni...

69

Design and implementation of Ethernet and E1 protocol convertor  

Microsoft Academic Search

Ethernet is widely used in social life. It has become an important infrastructure in the information society. Ethernet over synchronous digital hierarchy (SDH) is regarded as an economical and efficient scheme in the long-distance Ethernet interconnection. This paper considered the design of the Ethernet to E1 protocol converter, based on the frame granularity scheme which takes into account of miniaturization,

Dewei Yang; Hua Wang; Jingming Kuang; Yuquan Wang

2010-01-01

70

Measuring the strength of mice.  

PubMed

Kondziela devised the inverted screen test and published it in 1964. It is a test of muscle strength using all four limbs. Most normal mice easily score maximum on this task; it is a quick but insensitive gross screen, and the weights test described in this article will provide a finer measure of muscular strength. There are also several strain gauge-based pieces of apparatus available commercially that will provide more graded data than the inverted screen test, but their cost may put them beyond the reach of many laboratories which do not specialize in strength testing. Hence in 2000 a cheap and simple apparatus was devised by the author. It consists of a series of chain links of increasing length, attached to a "fur collector" a ball of fine wire mesh sold for preventing limescale build up in hard water areas. An accidental observation revealed that mice could grip these very tightly, so they proved ideal as a grip point for a weight-lifting apparatus. A common fault with commercial strength meters is that the bar or other grip feature is not thin enough for mice to exert a maximum grip. As a general rule, the thinner the wire or bar, the better a mouse can grip with its small claws. This is a pure test of strength, although as for any test motivational factors could potentially play a role. The use of scale collectors, however, seems to minimize motivational problems as the motivation appears to be very high for most normal young adult mice. PMID:23770643

Deacon, Robert M J

2013-01-01

71

Cavernous auto-injection therapy with prostaglandin E1.  

PubMed

During 1990-1992, 176 consecutive patients (aged 18-83 years, mean 53 years) with erectile dysfunction were personally investigated by the author in the private office setting at Eira Hospital. Pharmacotesting with 20 micrograms prostaglandin was positive in 89 of 138 patients (64%) tested. Eleven per cent of the patients complained of pain during erection. Of 131 patients, who initially were offered auto-injections as a primary treatment modality, 99 (76%) began the therapy. Seventy-four per cent of the patients continued auto-injections after three months. The overall efficacy of prostaglandin E1 to induce adequate erections for sexual intercourse was estimated to be 71%. One prolonged erection without medical intervention and no penile fibrotic lesions were recorded. In conclusion, cavernous auto-injection therapy with prostaglandin E1 is a well accepted, effective and safe treatment alternative in psychogenic as well as organic impotence. Every impotent patient should be informed of this therapy. PMID:8291874

Nisén, H

1993-01-01

72

On the strength of glass  

NASA Astrophysics Data System (ADS)

Glass has been ignored by most of the structural engineering community because of its brittle nature. Glass is an indispensable material in optical systems and sometimes safety, even human safety, depends upon optical glass elements to behave in a structurally reliable manner. One such occasion is to accommodate survey cameras in transport-class aircraft. Fortunately, glass has reliable structural properties and the methods for structural analysis and testing for glass have been well developed. Unfortunately, the glass suppliers have not chosen to publish the appropriate strength properties for many of their glasses. This paper describes the physics of the strength of glass and the engineering application of that physics to an airborne survey aircraft for the safety of its inhabitants.

Hatheway, Alson E.

2013-09-01

73

Skill, strength, handedness, and fatigue.  

PubMed

Thirty male subjects, 20 of whom were self-classified left-handers and 10 right-handers, were tested on a grip-strength task and a handwriting task with each hand, both under normal conditions and in a situation of induced experimental fatigue. On the basis of questionnaire scores, the left-handers were sub-divided into two groups comprising the 10 most left-handed and the 10 least left-handed subjects. The test of grip strength showed a small but significant deterioration in performance of both hands from fatigue. With the handwriting task, a similar significantly adverse effect of fatigue was recorded for all groups as well as a large significant difference in performance between the preferred and nonpreferred hands under normal conditions, which decreased under fatigue. An explanation of these differential effects is discussed in terms of the greater efficiency of the preferred hand in the highly developed skill of handwriting. PMID:15132940

Provins, K A; Magliaro, J

1989-06-01

74

Physical Strength and Job Performance  

NSDL National Science Digital Library

Created by David Lane of Rice University, this case study aims to answer the question, "How does one select employees to perform physically demanding jobs?" It examines the relationship between isometric strength tests and job performance for one hundred forty-seven workers. The author has structured the lesson to provide a background, methods and procedures, univariate statistics, scatter plots, correlations, regression and raw data. Some of the main concepts include: correlation, linear regression, multiple regression.

Lane, David M.

75

Strength Scaling in Fiber Composites  

NASA Technical Reports Server (NTRS)

A research program was initiated to study and isolate the factors responsible for scale effects in the tensile strength of graphite/epoxy composite laminates. Four layups were chosen with appropriate stacking sequences so as to highlight individual and interacting failure modes. Four scale sizes were selected for investigation including full scale size, 3/4, 2/4, and 1/4, with n = to 4, 3, 2, and 1, respectively. The full scale specimen sizes was 32 piles thick as compared to 24, 16, and 8 piles for the 3/4, 2/4, and 1/4 specimen sizes respectively. Results were obtained in the form of tensile strength, stress-strain curves and damage development. Problems associated with strength degradation with increasing specimen sizes are isolated and discussed. Inconsistencies associated with strain measurements were also identified. Enhanced x ray radiography was employed for damage evaluation, following step loading. It was shown that fiber dominated layups were less sensitive to scaling effects compared to the matrix dominated layups.

Kellas, Sotiris; Morton, John

1990-01-01

76

Mesenchymal Stem Cell Durotaxis Depends on Substrate Stiffness Gradient Strength  

PubMed Central

Mesenchymal stem cells (MSCs) respond to niche elasticity, which varies between and within tissues. Stiffness gradients result from pathological conditions but also occur through normal variation, e.g. muscle. MSCs undergo directed migration even in response to shallow stiffness gradients before differentiating. More refined gradients of both stiffness range and strength are needed to better understand mechanical regulation of migration in normal and disease pathologies. We describe polyacrylamide stiffness gradient fabrication using three distinct systems that generate stiffness gradients of physiological (1 Pa/µm), pathological (10 Pa/µm), and step (? 100Pa/um) strength spanning physiologically relevant stiffness for most soft tissue, i.e. 1–12 kPa. MSCs migrated to the stiffest region for each gradient. Time-lapse microscopy revealed that migration velocity scaled directly with gradient strength. Directed migration was reduced in the presence of the contractile agonist lysophosphatidic acid (LPA) and cytoskeletal-perturbing drugs nocodazole and cytochalasin; LPA- and nocodazole-treated cells remained spread and protrusive, while cytochalasin-treated cells did not. Untreated and nocodazole-treated cells spread in a similar manner, but nocodazole-treated cells had greatly diminished traction forces. These data suggest that actin is required for migration whereas microtubules are required for directed migration. The data also imply that in vivo, MSCs may have a more significant contribution to repairs in stiffer regions where they may preferentially accumulate. PMID:23390141

Vincent, Ludovic G.; Choi, Yu Suk; Alonso-Latorre, Baldomero; del Álamo, Juan C.; Engler, Adam J.

2013-01-01

77

B(E1) rates in {sup 229}Ra and traces of octupole correlations at the upper border of the A=225 island  

SciTech Connect

The introduction of the fast timing {beta}{gamma}{gamma}(t) method at ISOLDE (CERN) has opened the heavy actinide region to lifetime measurements down to tenths of picoseconds, providing a direct experimental means of measuring the E1 rates. Recently, this method has been successfully applied to {sup 229}Ra, located at the border of the A=225 island of octupole deformation. In the light of the new results, structural similarities are established between {sup 229}Ra and its N=141 isotone {sup 231}Th, investigated with the same technique. The comparison shows that some collective aspects of both nuclei are related, but that the strength of the E1 transitions presents interesting differences. The collective B(E1) rates are also discussed in comparison with neighboring nuclei in the upper border of the island of octupole deformation at A=225.

Fraile, L. M.; Borge, M. J. G. [Instituto de Estructura de la Materia, CSIC, Serrano 113 bis, E-28006 Madrid (Spain); Aas, A. J.; Hageboe, E. [Department of Chemistry, Univ. of Oslo, P.O. Box 1033, Blindern, N-0315 Oslo (Norway); Fogelberg, B.; Mach, H. [Department of Neutron Research, Univ. of Uppsala, S-61182 Nykoeping (Sweden); Garcia-Raffi, L. M.; Martinez, T.; Rubio, B.; Tain, J. L. [Instituto de Fisica Corpuscular, CSIC-Univ. Valencia, E-46100 Burjassot (Spain); Grant, I. S. [The Schuster Laboratory, Univ. of Manchester, Manchester M13 9PL (United Kingdom); Gulda, K.; Kurcewicz, W. [Department of Physics, Univ. of Warsaw, Pl-00 681 Warsaw (Poland); Loevhoeiden, G. [Department of Physics, Univ. of Oslo, P.O. Box 1048, Blindern, N-0316 Oslo (Norway); Tengblad, O. [Instituto de Estructura de la Materia, CSIC, Serrano 113 bis, E-28006 Madrid (Spain); EP Division, CERN, CH-1211 Geneva 23 (Switzerland); Thorsteinsen, T. F. [Department of Physics, Univ. of Bergen, N-5000 Bergen (Norway)

1999-11-16

78

Inert strength of pristine silica glass fibers  

SciTech Connect

Silica glass fibers have been produced and tested under ultra high vacuum (UHV) conditions to investigate the inert strength of pristine fibers in absence of reactive agents. Analysis of the coefficient of variation in diameter ({upsilon}{sub d}) vs the coefficient of variation of breaking strength ({upsilon}{sub {sigma}}) does not adequately explain the variation of breaking stress. Distribution of fiber tensile strength data suggests that the inert strength of such fibers is not single valued and that the intrinsic strength is controlled by defects in the glass. Furthermore, comparison of room temperature UHV data with LN{sub 2} data indicates that these intrinsic strengths are not temperature dependent.

Smith, W.L.; Michalske, T.A.

1993-11-01

79

{gamma}-strength functions in {sup 60}Ni from two-step cascades following proton capture  

SciTech Connect

The two-step cascade method previously used in neutron-capture experiments is now applied to a proton-capture reaction. The spectrum of two-step cascades populating the first 2{sup +} level of {sup 60}Ni has been measured with the {sup 59}Co(p,2{gamma}){sup 60}Ni reaction. The simulation technique used for the spectrum analysis allows one to reveal the range of possible shapes of both E1 and M1 {gamma}-strength functions. The low-energy enhancement previously observed in {sup 3}He-induced reactions is seen to appear in M1 strength functions of {sup 60}Ni.

Voinov, A.; Grimes, S. M.; Brune, C. R.; Massey, T. N.; Schiller, A. [Department of Physics and Astronomy, Ohio University, Athens, Ohio 45701 (United States); Guttormsen, M.; Larsen, A. C.; Siem, S. [Department of Physics, University of Oslo, N-0316 Oslo (Norway)

2010-02-15

80

RP-1 delivered to E-1 Test Stand  

NASA Technical Reports Server (NTRS)

NASA John C. Stennis Space Center employee Dustan Ladner (left) assists tanker driver David Velasco in transferring RP-1 fuel to a 20,000-gallon underground tank at the E-1 Test Stand during a March 30 delivery. The rocket propellant will be used for testing Aerojet AJ26 rocket engines beginning this summer. Stennis is testing the engines for Orbital Sciences Corporation, which has partnered with NASA to provide eight supply missions to the International Space Station through 2015. The partnership is part of NASA's Commercial Orbital Transportation Services initiative to work closer with companies to provide commercial space transport once the space shuttle is retired later this year.

2010-01-01

81

> ml -m E[1 _..!-]2 >ml -mflg m1.  

E-print Network

> ml - m E[1 _..!-]2 i i=O m >ml -mflg m1. It follows that E[r] > m(E[IpsI] - flgm1). Since Vl-l is just some subset of R then E[N] ~ E[r] and mE[psI] > m(E[IpsI] - fig m1). Solving for E[lpsl] we get E[IpsI] m1. The lower bound holds because psI ::; IpsI for every table. 0 Corollary

Rosin, Paul

82

Dielectric strength of parylene HT  

SciTech Connect

The dielectric strength of parylene HT (PA-HT) films was studied at room temperature in a wide thickness range from 500?nm to 50??m and was correlated with nano- and microstructure analyses. X-ray diffraction and polarized optical microscopy have revealed an enhancement of crystallization and spherulites development, respectively, with increasing the material thickness (d). Moreover, a critical thickness d{sub C} (between 5 and 10??m) is identified corresponding to the beginning of spherulite developments in the films. Two distinct behaviors of the dielectric strength (F{sub B}) appear in the thickness range. For d???d{sub C}, PA-HT films exhibit a decrease in the breakdown field following a negative slope (F{sub B}???d{sup ?0.4}), while for d?strength (F{sub B}???10 MV/cm) is obtained. A model of spherulite development in PA-HT films with increasing the thickness is proposed. The decrease in F{sub B} above d{sub C} is explained by the spherulites development, whereas its increase below d{sub C} is induced by the crystallites growth. An annealing of the material shows both an enhancement of F{sub B} and an increase of the crystallites and spherulites dimensions, whatever the thickness. The breakdown field becomes thickness-independent below d{sub C} showing a strong influence of the nano-scale structural parameters. On the contrary, both nano- and micro-scale structural parameters appear as influent on F{sub B} for d???d{sub C}.

Diaham, S., E-mail: sombel.diaham@laplace.univ-tlse.fr; Bechara, M.; Locatelli, M.-L.; Khazaka, R. [Université de Toulouse, UPS, INPT, LAPLACE, 118 route de Narbonne-Bât. 3R3, F-31062 Toulouse Cedex 9 (France); CNRS, LAPLACE, F-31062 Toulouse (France); Tenailleau, C. [Université de Toulouse, UPS, Laboratoire CIRIMAT/LCMIE, 118 route de Narbonne-Bât. 2R1, F-31062 Toulouse Cedex 9 (France); Kumar, R. [Speciality Coating Systems, Inc. (SCS), Cookson Electronics, 7645 Woodland Drive, Indianapolis, Indiana 46278 (United States)

2014-02-07

83

Joint strength in RCS frames  

E-print Network

. 2 Specimen 2. . . . . . . 4. 5. 2. 3 Specimen 3 4. 5. 2. 4 Specimen 4, 4. 6 PREDICTED FAILURE MECHANISMS (CONTINUOUS BEAM DIRECTION) . . 4. 6. 1 ASCE Design Equations (ASCE 1994) 4 6, 1. 1 Joint Panel Shear 4. 6. 1. 2 Vertical Bearing . 4. 6... Vertical Bearing. 4. 6. 4 Beam Failure Mechanism. Page 4. 6. 5 Column Failure Mechanism 4. 6. 6 Predicted Failure Mechanisms 4. 7 JOINT STRENGTH PREDICTIONS (DISCONTINUOUS BEAM DIRECTION). 5. RESPONSE 5. 1 INTRODUCTION . . 5. 2. GENERAL BEHAVIOR 5...

Kirby, Cynthia Dawn

1998-01-01

84

46 CFR 177.1020 - Strength.  

Code of Federal Regulations, 2011 CFR

46 Shipping 7 2011-10-01 2011-10-01 false Strength...100 GROSS TONS) CONSTRUCTION AND ARRANGEMENT Window Construction and Visibility § 177.1020 Strength. Each window, port hole, and its means of attachment to...

2011-10-01

85

46 CFR 177.1020 - Strength.  

Code of Federal Regulations, 2010 CFR

46 Shipping 7 2010-10-01 2010-10-01 false Strength...100 GROSS TONS) CONSTRUCTION AND ARRANGEMENT Window Construction and Visibility § 177.1020 Strength. Each window, port hole, and its means of attachment to...

2010-10-01

86

46 CFR 177.1020 - Strength.  

Code of Federal Regulations, 2013 CFR

46 Shipping 7 2013-10-01 2013-10-01 false Strength...100 GROSS TONS) CONSTRUCTION AND ARRANGEMENT Window Construction and Visibility § 177.1020 Strength. Each window, port hole, and its means of attachment to...

2013-10-01

87

46 CFR 177.1020 - Strength.  

Code of Federal Regulations, 2012 CFR

46 Shipping 7 2012-10-01 2012-10-01 false Strength...100 GROSS TONS) CONSTRUCTION AND ARRANGEMENT Window Construction and Visibility § 177.1020 Strength. Each window, port hole, and its means of attachment to...

2012-10-01

88

14 CFR 31.27 - Strength.  

Code of Federal Regulations, 2014 CFR

...and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: MANNED FREE BALLOONS Strength Requirements § 31.27 Strength. (a) The structure must be able to support limit loads without...

2014-01-01

89

14 CFR 31.27 - Strength.  

Code of Federal Regulations, 2012 CFR

...and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: MANNED FREE BALLOONS Strength Requirements § 31.27 Strength. (a) The structure must be able to support limit loads without...

2012-01-01

90

14 CFR 31.27 - Strength.  

Code of Federal Regulations, 2010 CFR

...and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: MANNED FREE BALLOONS Strength Requirements § 31.27 Strength. (a) The structure must be able to support limit loads without...

2010-01-01

91

14 CFR 31.27 - Strength.  

Code of Federal Regulations, 2013 CFR

...and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: MANNED FREE BALLOONS Strength Requirements § 31.27 Strength. (a) The structure must be able to support limit loads without...

2013-01-01

92

14 CFR 31.27 - Strength.  

Code of Federal Regulations, 2011 CFR

...and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: MANNED FREE BALLOONS Strength Requirements § 31.27 Strength. (a) The structure must be able to support limit loads without...

2011-01-01

93

Strength distribution in commercial silicon carbide materials  

NASA Technical Reports Server (NTRS)

Four-point flexural strength testing has been conducted in order to establish the baseline strength and reliability of four different commercial SiC types, in conjunction with reliable Weibull modulus values. Average strength of the samples ranged from 380 to 482 MPa at room temperature and 307 to 470 MPa at 1370 C. The strength scatter reflects the effect of flaw variability, which must be minimized to improve reliability in sintered SiC.

Dutta, Sunil

1988-01-01

94

PREDICTING TIE STRENGTH WITH SOCIAL MEDIA  

E-print Network

PREDICTING TIE STRENGTH WITH SOCIAL MEDIA Eric Gilbert & Karrie Karahalios University of Illinois #12;casey leslielucas kevin #12;The strength of a tie is a (probably linear) combination of the amount characterize the tie. -- Granovetter TIE STRENGTH concept & impact STRONG TIES are the people you really trust

Karahalios, Karrie G.

95

Maximal Strength Testing in Healthy Children  

Microsoft Academic Search

Strength training has become an accepted method of con- ditioning in children. However, there is concern among some observers that maximal strength testing may be inappropri- ate or potentially injurious to children. The purpose of this study was to evaluate the safety and efficacy of 1 repetition maximum (1RM) strength testing in healthy children. Thirty- two girls and 64 boys

AVERY D. FAIGENBAUM; LAURIE A. MILLIKEN; WAYNE L. WESTCOTT

2003-01-01

96

Strength of composite lattice structures  

NASA Astrophysics Data System (ADS)

This research investigates the strength of composite latticed cylindrical and conical shells under axial compressive loads. The latticed structures are composed of circumferential and helical members, whose cross-sections are rectangular. This research examines the failure modes of both cylindrical and conical composite latticed shells. New design constraints to achieve weight efficient structures with high failure loads is presented. Two main failure modes, general buckling as a shell and excessive shear stress in the members, are considered. The main emphasis is placed on the effects of geometrical configuration of the structure and the manufacturing process. In order to automate the fabrication process and to minimize manufacturing costs, filament winding was chosen as the method of construction. Numerical results are obtained by finite element analysis which are compared with experimental solutions. The motivation of the present work is to find the optimal winding pattern which filament winding can be easily applied and still provides the highest strength to weight ratio. The final result of this research includes the numerical and experimental analysis of composite latticed cylindrical and conical shells via filament-winding. This work should provide a comprehensive understanding of composite latticed structures that will be useful in preliminary design of such structures.

Hou, An

97

Nondestructive Determination of Bond Strength  

NASA Technical Reports Server (NTRS)

Although many nondestructive techniques have been applied to detect disbonds in adhesive joints, no absolutely reliable nondestructive method has been developed to detect poor adhesion and evaluate the strength of bonded joints prior to the present work which used nonlinear ultrasonic methods to investigate adhesive bond cure conditions. Previously, a variety of linear and nonlinear ultrasonic methods with water coupling had been used to study aluminum-adhesive-aluminum laminates, prepared under different adhesive curing conditions, for possible bond strength determination. Therefore, in the course of this research effort, a variety of finite-amplitude experimental methods which could possibly differentiate various cure conditions were investigated, including normal and oblique incidence approaches based on nonlinear harmonic generation as well as several non-collinear two-wave interaction approaches. Test samples were mechanically scanned in various ways with respect to the focus of a transmitting transducer operated at several variable excitation frequencies and excitation levels. Even when powerful sample-related resonances were exploited by means of a frequency scanning approach, it was very difficult to isolate the nonlinear characteristics of adhesive bonds. However, a multi-frequency multi-power approach was quite successful and reliable. Ultrasonic tone burst signals at increasing power levels, over a wide frequency range, were transmitted through each bond specimen to determine its excitation dependent nonlinear harmonic resonance behavior. Relative amplitude changes were observed particularly in the higher harmonic spectral data and analyzed using a local displacement and strain analysis in the linear approximation. Two analysis approaches of the excitation-dependent data at specific resonances were found to be quite promising. One of these approaches may represent a very robust algorithm for classifying an adhesive bond as being properly cured or not. Another approach, in addition to differentiation between various cure conditions, may even provide information with respect to the bond strength. Several technical papers were published during the course of this research and a summary is presented in the Ph.D. dissertation of Tobias P. Berndt, a graduate student financially supported by this NASA Grant.

2000-01-01

98

Decrease in grip strength induced by simultaneous bilateral exertion with reference to finger strength  

Microsoft Academic Search

Voluntary maximum isometric grip strength was measured under the conditions of simultaneous bilateral and separate unilateral exertion on 16 male and 8 female subjects. Strengths of each finger and surface electromyograms of finger flexors in the forearm were recorded concurrently with grip strength recording. The Following results were obtained: (1) Grip strength and integrated EMG of both arms were significantly

TATSUYUKI OHTSUKI

1981-01-01

99

Determination of the dividing strength and its relation to the concrete strength in lightweight aggregate concrete  

Microsoft Academic Search

As concrete is considered to be a composite material consisting of mortar and coarse aggregate, its strength depends on the mortar strength and coarse aggregate strength. During the strength development stage of a lightweight aggregate concrete, a critical condition, under which the type of stress distribution changes, occurs as the values of the modulus of elasticity of the lightweight aggregate

H. J. Chen; T. Yen; T. P. Lia; Y. L. Huang

1999-01-01

100

The Strengths Assessment Inventory: Reliability of a New Measure of Psychosocial Strengths for Youth  

ERIC Educational Resources Information Center

A new measure, the Strengths Assessment Inventory-Youth self-report (SAI-Y), was recently developed to assess the strengths of children and adolescents between the ages of 10 and 18 years. The SAI-Y differs from similar measures in that it provides a comprehensive assessment of strengths that are intrinsic to the individual as well as strengths

Brazeau, James N.; Teatero, Missy L.; Rawana, Edward P.; Brownlee, Keith; Blanchette, Loretta R.

2012-01-01

101

Oscillator strengths for OII ions  

NASA Technical Reports Server (NTRS)

Oscillator strengths between various doublet states of OII ions are calculated in which extensive multi-configuration wave functions are used. The lower levels for the transitions are of the 2p(3) D(2)o and 2p(3) 2po states, and the upper levels are 2p(4), 3s, and 3d states. The results, which are estimated to have errors of less than 10% for individual transitions, agree quite well with the beam foil experiments, as well as with the calculations by use of the non-closed shell many electron theory (NCMET). The agreement with the rocket measurements is also good except for the 538/581 A pair, in which the 538 A line is believed to be blend with the other stronger quartet line. However, a comparison with the recent branching ratio measurement indicates that discrepances between the present calculation and th experiment do exist for certain transistions.

Ho, Y. K.; Henry, J. W.

1983-01-01

102

Strength of Welded Aircraft Joints  

NASA Technical Reports Server (NTRS)

This investigation is a continuation of work started in 1928 and described in NACA-TR-348 which shows that the insertion of gusset plates was the most satisfactory way of strengthening a joint. Additional tests of the present series show that joints of this type could be improved by cutting out the portion of the plate between the intersecting tubes. T and lattice joints in thin-walled tubing 1 1/2 by 0.020 inch have somewhat lower strengths than joints in tubing of greater wall thickness because of failure by local buckling. In welding the thin-walled tubing, the recently developed "carburizing flux" process was found to be the only method capable of producing joints free from cracks. The "magnetic powder" inspection was used to detect cracks in the joints and flaws in the tubing.

Brueggeman, W C

1937-01-01

103

Metabolism of prostaglandins A1 and E1 in man.  

PubMed Central

To investigate the in vivo whole blood metabolic clearance rates and sites of metabolism of prostaglandins A1 and E1 in man, constant infusions of the tritiated compounds were administered to normal subjects and to patients undergoing cardiac catheterization. The whole blood metabolic clearance rate of [3H]prostaglandin A1 in eight men was 5,003 +/- 864 liters/day (SD) or 2,546 +/- 513 liters/day per m2 (SD). Nonradioactive prostaglandin A1 was similarly infused in two subjects, and the metabolic clearance rates were determined, utilizing a specific radioimmunoassay. The clearance rates with this method correlated closely with those determined by the isotope infusions. Extraction studies of prostaglandin A1 showed that pulmonary, splanchnic, renal, and extremity perfusions resulted in 8.1 +/- 4.1, 56.1 +/- 10.1, 50.3 +/- 3.4, and 34.4 +/- 5.9% (SEM) removal, respectively. With [3H]=prostaglandin E1, the whole blood metabolic clearance rate was determined from the pulmonary artery concentration in three patients and averaged 4,832 +/- 1,518 liters/day (SD) or 2,686 +/- 654 liters/day per m2 (SD). Pulmonary extraction was 67.8 +/- 6.8% (SEM) and extremity removal averaged 6.6 +/- 4.9% (SEM). These results indicate that A prostaglandins are metabolized by several organs, such as the liver and kidney, and possibly by intravascular pathways as well. In man, the E prostaglandins are primarily metabolized by the lung, but extraction is not complete and approximately one-third may escape lung metabolism. Thus, these findings suggest that both E and A prostaglandins in the venous circulation may reach the systemic circulation in man. PMID:1202078

Golub, M; Zia, P; Matsuno, M; Horton, R

1975-01-01

104

Improved Plant-based Production of E1 endoglucanase Using Potato: Expression Optimization and Tissue Targeting  

SciTech Connect

Optimization of Acidothermus cellulolyticus endoglucanase (E1) gene expression in transgenic potato (Solanum tuberosum L.) was examined in this study, where the E1 coding sequence was transcribed under control of a leaf specific promoter (tomato RbcS-3C) or the Mac promoter (a hybrid promoter of mannopine synthase promoter and cauliflower mosaic virus 35S promoter enhancer region). Average E1 activity in leaf extracts of potato transformants, in which E1 protein was targeted by a chloroplast signal peptide and an apoplast signal peptide were much higher than those by an E1 native signal peptide and a vacuole signal peptide. E1 protein accumulated up to 2.6% of total leaf soluble protein, where E1 gene was under control of the RbcS-3C promoter, alfalfa mosaic virus 5-untranslated leader, and RbcS-2A signal peptide. E1 protein production, based on average E1 activity and E1 protein accumulation in leaf extracts, is higher in potato than those measured previously in transgenic tobacco bearing the same transgene constructs. Comparisons of E1 activity, protein accumulation, and relative mRNA levels showed that E1 expression under control of tomato RbcS-3C promoter was specifically localized in leaf tissues, while E1 gene was expressed in both leaf and tuber tissues under control of Mac promoter. This suggests dual-crop applications in which potato vines serve as enzyme production `bioreactors' while tubers are preserved for culinary applications.

Dai, Ziyu; Hooker, Brian S.; Anderson, Daniel B.; Thomas, S R.

2000-06-01

105

Serum autoantibodies against cytochrome P450 2E1 (CYP2E1) predict severity of necroinflammation of recurrent hepatitis C.  

PubMed

We previously reported that autoantibodies against cytochrome P4502E1 (CYP2E1) are frequent in patients with chronic hepatitis C. As autoimmune reactions are increasingly detected after orthotopic liver transplantation (OLT), this study investigates prevalence and significance of anti-CYP2E1 autoantibodies in 46 patients with post-OLT recurrent hepatitis C. IgG against recombinant human CYP2E1 above the control threshold was detected in 19 out 46 (41%) sera collected immediately before OLT and in 15 out 46 (33%) sera collected at the time of the 12 months follow-up liver biopsy. Although anti-CYP2E1 reactivity was not modified by OLT, the patients with persistently elevated anti-CYP2E1 IgG (n = 12; 26%) showed significantly higher prevalence of recurrent hepatitis with severe necroinflammation and fibrosis than those persistently negative or positive only either before or after OLT. Moreover, the probability of developing severe necroinflammation was significantly higher in persistently anti-CYP2E1-positive subjects. Multivariate regression and Cox analysis confirmed that the persistence of anti-CYP2E1 IgG, together with a history of acute cellular rejection and donor age >50 years, was an independent risk factor for developing recurrent hepatitis C with severe necroinflammation. We propose that autoimmune reactions involving CYP2E1 might contribute to hepatic damage in a subgroup of transplanted patients with recurrent hepatitis C. PMID:19191768

Rigamonti, C; Vidali, M; Donato, M F; Sutti, S; Occhino, G; Ivaldi, A; Arosio, E; Agnelli, F; Rossi, G; Colombo, M; Albano, E

2009-03-01

106

Microscopic nature of the photon strength function: stable and unstable Ni and Sn isotopes  

E-print Network

The pygmy-dipole resonances and photon strength functions in stable and unstable Ni and Sn isotopes are calculated within the microscopic self-consistent version of the extended theory of finite fermi systems which includes the QRPA and phonon coupling effects and uses the known Skyrme forces SLy4. The pygmy dipole resonance in $^{72}Ni$ is predicted with the mean energy of 12.4 MeV and the energy-weighted sum rule exhausting 25.6\\% of the total strength. The microscopically obtained photon E1 strength functions are used to calculate nuclear reaction properties, i.e the radiative neutron capture cross section, gamma-ray spectra, and average radiative widths. Our main conclusion is that in all these quantities it is necessary to take the phonon coupling effects into account.

Oleg Achakovskiy; Alexander Avdeenkov; Stephane Goriely; Sergei Kamerdzhiev; Siegfried Krewald; Dmitriy Voitenkov

2014-10-16

107

Nucleus accumbens and impulsivity Koray Basar a,c,e,1  

E-print Network

Nucleus accumbens and impulsivity Koray Basar a,c,e,1 , Thibaut Sesia b,c,e,1 , Henk Groenewegen d . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 537 3. Impulsivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 538 3.1. Attentional/reflection impulsivity

108

A p300\\/CBP-associated factor that competes with the adenoviral oncoprotein E1A  

Microsoft Academic Search

The adenoviral oncoprotein E1A induces progression through the cell cycle by binding to the products of the p300\\/CBP and retinoblastoma gene families. A new cellular p300\\/CBP-associated factor (P\\/CAF) having intrinsic histone acetylase activity has been identified that competes with E1A. Exogenous expression of P\\/CAF in HeLa cells inhibits cell-cycle progression and counteracts the mitogenic activity of E1A. E1A disturbs the

Xiang-Jiao Yang; Vasily V. Ogryzko; Jun-Ichi Nishikawa; Bruce H. Howard; Yoshihiro Nakatani

1996-01-01

109

Fracture strength of silicon solar cells  

NASA Technical Reports Server (NTRS)

A test program was developed to determine the nature and source of the flaw controlling the fracture of silicon solar cells and to provide information regarding the mechanical strength of cells. Significant changes in fracture strengths were found in seven selected in-process wafer-to-cell products from a manufacturer's production line. The fracture strength data were statistically analyzed and interpreted in light of the exterior flaw distribution of the samples.

Chen, C. P.

1979-01-01

110

Strength of Silicon Wafers: Fracture Mechanics Approach  

SciTech Connect

This paper describes a model to predict mechanical strength distribution of silicon wafers. A generalized expression, based on a multimodal Weibull distribution, is proposed to describe the strength of a brittle material with surface, edge, and bulk flaws. The specific case of a cast, unpolished photovoltaic (PV) wafer is further analyzed. Assuming that surface microcracks constitute the dominant mechanism of wafer breakage, this model predicts the strength distribution of PV silicon that matches well the experimental results available in the literature.

Rupnowski, P.; Sopori, B.

2009-01-01

111

26 CFR 1.1402(e)-1A - Application of regulations under section 1402(e).  

Code of Federal Regulations, 2010 CFR

...Revenue 12 2010-04-01 2010-04-01 false Application of regulations under section 1402(e). 1.1402(e)-1A Section 1.1402(e)-1A Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED)...

2010-04-01

112

Dynamic TCP Acknowledgement and Other Stories about e/(e-1)  

E-print Network

Dynamic TCP Acknowledgement and Other Stories about e/(e-1) #3; Anna R. Karlin y Claire Kenyon z demonstrate that a number of online algorithms which have optimal competitive ratios of e=(e 1), including], and a randomized online algorithm that achieves a competitive ratio of e=(e 1) (which is about 1.58) in the limit

Kenyon, Claire

113

Accelerated Strength Testing of Thermoplastic Composites  

NASA Technical Reports Server (NTRS)

Constant ramp strength tests on unidirectional thermoplastic composite specimens oriented in the 90 deg. direction were conducted at constant temperatures ranging from 149 C to 232 C. Ramp rates spanning 5 orders of magnitude were tested so that failures occurred in the range from 0.5 sec. to 24 hrs. (0.5 to 100,000 MPa/sec). Below 204 C, time-temperature superposition held allowing strength at longer times to be estimated from strength tests at shorter times but higher temperatures. The data indicated that a 50% drop in strength might be expected for this material when the test time is increased by 9 orders of magnitude. The shift factors derived from compliance data applied well to the strength results. To explain the link between compliance and strength, a viscoelastic fracture model was investigated. The model, which used compliance as input, was found to fit the strength data only if the critical fracture energy was allowed to vary with temperature reduced stress rate. This variation in the critical parameter severely limits its use in developing a robust time-dependent strength model. The significance of this research is therefore seen as providing both the indication that a more versatile acceleration method for strength can be developed and the evidence that such a method is needed.

Reeder, J. R.; Allen, D. H.; Bradley, W. L.

1998-01-01

114

Strength properties of separators in alkaline solutions  

SciTech Connect

Battery separator non-wovens that were coated with regenerated cellulose via the viscose process were subjected to storage in 40% potassium hydroxide (KOH) over a two month period. Samples were periodically checked for wet MD tensile strength. The test showed that among the non-wovens, the polyamide retained about 93% of its initial tensile strength whereas polyvinyl alcohol and cellulosic non-wovens retained only 55% and 35%, respectively. Adding a viscose coating to the non-wovens improved tensile strength retention by 20--25% for the polyvinyl alcohol and cellulosic materials. The viscose-coated polyamide retained more than 98% of its initial tensile strength.

Danko, T. [Viskase Corp., Chicago, IL (United States)

1996-11-01

115

Imparting strength and toughness to brittle composites  

NASA Technical Reports Server (NTRS)

Appropriate intermittent coatings of fibers can produce areas of low and high toughness in brittle composites. Experiments using silicon vacuum grease (SVG) and polyurethane varnish (PUV) coatings that achieve weakly and strongly bonded interfaces are described. Tensile strength and edge-crack fracture toughness for both SVG and PUV coatings were plotted against the percentage coating (C). Both coating materials maintain tensile strengths in the order of the rule of mixture strength values up to a large C. It is suggested that both materials produce similar coated interfacial shear strengths while producing different effects on toughness.

Atkins, A. G.

1974-01-01

116

Development of strength in solidifying aluminium alloys  

SciTech Connect

Quantitative measurements of the strength development in the mushy-zone during solidification have been obtained in two commercial Al-Si alloys, AlSi7Mg and AlSi11Mg, an AlCu4 alloy and an AlMg5 alloy with a vane method. The results show that the material does not have any strength prior to dendrite coherency, confirming that the dendrites are free-floating and independent. Grain refining the AlSi7Mg and AlCu4 alloy postpones strength development, and strength increases slowly in the grain refined AlCu4 alloy. Adding Sr to the AlSi7Mg alloy postpones dendrite coherency and strength develops more slowly. Fading is observed to change the strength back towards that of the unmodified alloy with time. Adding 1% Si to the AlMg5 alloy postpones dendrite coherency, but the strength increases rapidly and makes the strength of the AlMg5Si1 alloy converge towards that of the AlMg5 alloy at increasing solid fractions. Strength develops very slowly in the AlSi11Mg alloy. The results are shown to be related to the size and morphology of the growing dendrites.

Dahle, A.K.; Arnberg, L. [Norwegian Univ. of Science and Technology, Trondheim (Norway). Dept. of Metallurgy] [Norwegian Univ. of Science and Technology, Trondheim (Norway). Dept. of Metallurgy

1997-02-01

117

E1-forbidden transition rates in ions of astrophysical interest  

NASA Astrophysics Data System (ADS)

Transition rates in atomic systems may appear to be of little importance in steady-state plasmas that are observed at great distances from Earth. However, some of the transition rates compete with collision rates, and in these cases certain line intensity ratios are affected and can serve as remote indicators of density. In the low-density environments of stellar coronae and planetary nebulae, the transition rates of interest are mostly spin-forbidden E1 decays, higher-multipole order transitions (M1, E2, M2, M3), and hyperfine-induced transitions. On Earth, measurements of the long upper level lifetimes of these atomic systems require the use of ion traps. A fair number of test cases with lifetimes in the range from nanoseconds to many seconds have been treated successfully, and the evolution of calculations along with the experimental progress is notable. A new generation of cold ion traps is expected to extend the atomic lifetime measurements on multiply charged ions into the range of many minutes.

Träbert, E.

2014-11-01

118

Specimen shape and size effect on the compressive strength of higher strength concrete  

SciTech Connect

The specimen size and shape effects on the compressive strength of higher strength concrete were investigated on different sized cylinders having constant length-to-diameter ratio (l/d), different sized cubes, and cylinders with various l/d for 40, 60, and 75 MPa compressive strength levels. The apparent strength values of 75 mm diameter cylinder and 75 and 100mm cube specimens were lower than those of the larger specimens used. Also, the compressive strength was determined to be insignificantly affected by changing l/d as the strength of concrete increases.

Tokyay, M. [Middle East Technical Univ., Ankara (Turkey). Civil Engineering Dept.] [Middle East Technical Univ., Ankara (Turkey). Civil Engineering Dept.; Oezdemir, M. [ERG Construction Co., Ankara (Turkey)] [ERG Construction Co., Ankara (Turkey)

1997-08-01

119

Strength Development and Motor-Sports Improvement.  

ERIC Educational Resources Information Center

This document examines the effects of strength-development programs on the improvement of motor skills and sports competencies. Part one defines various terms used throughout the development studies. Part two discusses the mixed results of experiments involving speed of movement as the motor item indicative of strength development. Part three…

Clarke, H. Harrison, Ed.

1974-01-01

120

The genetic architecture of maize stalk strength  

Technology Transfer Automated Retrieval System (TEKTRAN)

Stalk strength is an important trait in maize (Zea mays L.). Strong stalks reduce lodging and maximize harvestable yield. Studies show rind penetrometer resistance (RPR), or the force required to pierce a stalk rind with a spike, is a valid approximation of strength. We measured RPR across 4,892 rec...

121

The Strengths Revolution: A Positive Psychology Perspective  

ERIC Educational Resources Information Center

Christopher Peterson received the Circle of Courage Award and made the following address in a symposium on "The Strength-Based Revolution" at Wayne State University in Detroit, Michigan (Peterson & Brendtro, 2008). Dr. Peterson shared personal reflections on the strengths movement, which is transforming youth development. His presentation shows…

Peterson, Christopher

2013-01-01

122

Enhancement of dielectric strength in nanocomposites  

Microsoft Academic Search

In this paper, we report the dielectric breakdown properties of a nanocomposite, a potential electrical insulation material for cryogenic high voltage applications. The material is composed of a high molecular weight polyvinyl alcohol and nanosized in situ synthesized titanate particles. The dielectric breakdown strengths of the filled material samples, measured in liquid nitrogen, indicate a significant increase in their strengths

Enis Tuncer; Isidor Sauers; David Randy James; Alvin R. Ellis; Mariappan Parans Paranthaman; Amit Goyal; Karren Leslie More

2007-01-01

123

Scaling strength in human simulation models  

Microsoft Academic Search

Introduction: Simulating human movement, with multi-body models, enables virtual experiments that are too difficult, costly or dangerous to perform in reality. When simulation models are used for subject specific goals, like planning a rehabilitation intervention, it is important that they are based on subject-specific data. Therefore, accurate strength scaling, accounting for subject specific differences, is required. Unfortunately, current strength scaling

Annegarn J; Rasmussen J; Savelberg HHCM; Verdijk LB; Meijer K

124

Optimizing header strength utilizing finite element analyses  

Microsoft Academic Search

Finite element techniques have been successfully applied as a design tool in the optimization of high strength headers for pyrotechnic-driven actuators. These techniques have been applied to three aspects of the design process of a high strength header. The design process was a joint effort of experts from several disciplines including design engineers, material scientists, test engineers, manufacturing engineers, and

S. N. Burchett

1986-01-01

125

14 CFR 23.627 - Fatigue strength.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Fatigue strength. 23.627 Section 23.627...Design and Construction § 23.627 Fatigue strength. The structure must be...concentration where variable stresses above the fatigue limit are likely to occur in normal...

2010-01-01

126

14 CFR 23.627 - Fatigue strength.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 2012-01-01 false Fatigue strength. 23.627 Section 23.627...Design and Construction § 23.627 Fatigue strength. The structure must be...concentration where variable stresses above the fatigue limit are likely to occur in normal...

2012-01-01

127

14 CFR 23.627 - Fatigue strength.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Fatigue strength. 23.627 Section 23.627...Design and Construction § 23.627 Fatigue strength. The structure must be...concentration where variable stresses above the fatigue limit are likely to occur in normal...

2013-01-01

128

14 CFR 23.627 - Fatigue strength.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 2011-01-01 false Fatigue strength. 23.627 Section 23.627...Design and Construction § 23.627 Fatigue strength. The structure must be...concentration where variable stresses above the fatigue limit are likely to occur in normal...

2011-01-01

129

Effect of reinforcement corrosion on bond strength  

Microsoft Academic Search

The effect of reinforcement corrosion on the bond strength between steel and concrete was investigated. The bond behaviour of reinforced concrete elements, including the ultimate bond strength, free-end slip, and the modes of failure in precracking, cracking and postcracking stages was studied. Also, the effect of different crack widths and the rib profile degradation for various degrees of corrosion on

Abdullah A. Almusallam; Ahmad S. Al-Gahtani; Abdur Rauf Aziz; Rasheeduzzafar

1996-01-01

130

Giant monopole strength in Ni-58  

E-print Network

The strength distribution of the giant monopole resonance in Ni-58 has been measured from E-x = 10 to 35 MeV using small-angle scattering of 240-MeV alpha particles. E0 strength corresponding to 74(-12)(+22)% of the E0 EWSR was found between E...

Lui, YW; Clark, HL; Youngblood, David H.

2000-01-01

131

Strength enhancement process for prealloyed powder superalloys  

NASA Technical Reports Server (NTRS)

A technique involving superplastic processing and high pressure autoclaving was applied to a nickel base prealloyed powder alloy. Tensile strengths as high as 2865 MN/sq m at 480 C were obtained with as-superplastically deformed material. Appropriate treatments yielding materials with high temperature tensile and stress rupture strengths were also devised.

Waters, W. J.; Freche, J. C.

1977-01-01

132

Strength and Fatigue Life of Wire Rope  

Microsoft Academic Search

A method is presented that predicts the fatigue life of a large diameter wire rope, from test data for small diameter rope. Dimensional analysis and the technique of interpolation and extrapolation are employed. The method is applied first to study size effects on the breaking strength of wire ropes and then to predict fatigue strength. Results are compared with experimental

Chi-Hui Chien; Raymond A. LeClair; George A. Costello

1988-01-01

133

Testing Spaghetti's Strength, or Lots of Pastabilities.  

ERIC Educational Resources Information Center

Describes a classroom activity that explores the strength of spaghetti. Provides students an opportunity to explore a common substance in a scientific way; measure the strength of various sizes and amounts of spaghetti; gather, record, and translate quantitative data; use calculators; and present data. (YDS)

McDuffie, Thomas E., Jr.

2000-01-01

134

Adolescents' Self-Perceptions of Their Strengths.  

ERIC Educational Resources Information Center

Adolescents in New Zealand (492 boys and 468 girls) completed a 22-item scale concerning their self-perceived strengths. Parent, peer, and school attachment, part-time work, and number of physical activities in which they were involved (NPAs) were central for boys. Girls' strengths were best predicted by parent attachment and NPAs. (TJH)

Williams, Sheila; McGee, Rob

1991-01-01

135

SIZE EFFECT ON COMPRESSIVE STRENGTH OF CONCRETE  

Microsoft Academic Search

It is important to consider an effect of a member size when estimating the ultimate strength of a concrete member loaded for all types of loading conditions. As well known as size effect, the strength of a member tends to decrease when the member sizes increase. Therefore, due to the recent increased interest in the topic of size effect of

J. K. Kim

136

Specimen shape and size effect on the compressive strength of higher strength concrete  

Microsoft Academic Search

The specimen size and shape effects on the compressive strength of higher strength concrete were investigated on different sized cylinders having constant length-to-diameter ratio (ld), different sized cubes, and cylinders with various ld for 40, 60, and 75 MPa compressive strength levels. The apparent strength values of 75mm diameter cylinder and 75 and 100mm cube specimens were lower than those

M. Tokyay; M. Özdemir

1997-01-01

137

Factors which affect fatigue strength of fasteners  

SciTech Connect

Axial load cycling fatigue tests of threaded fasteners are useful in determining fastener fatigue failure or design properties. By using appropriate design factors between the failure and design fatigue strengths, such tests are used to establish fatigue failure and design parameters of fasteners for axial and bending cyclic load conditions. This paper reviews the factors which influence the fatigue strength of low Alloy steel threaded fasteners, identifies those most significant to fatigue strength, and provides design guidelines based on the direct evaluation of fatigue tests of threaded fasteners. Influences on fatigue strength of thread manufacturing process (machining and rolling of threads), effect of fastener membrane and bending stresses, thread root radii, fastener sizes, fastener tensile strength, stress relaxation, mean stress, and test temperature are discussed.

Skochko, G.W.; Herrmann, T.P.

1992-11-01

138

Factors which affect fatigue strength of fasteners  

NASA Astrophysics Data System (ADS)

Axial load cycling fatigue tests of threaded fasteners are useful in determining fastener fatigue failure or design properties. By using appropriate design factors between the failure and design fatigue strengths, such tests are used to establish fatigue failure and design parameters of fasteners for axial and bending cyclic load conditions. This paper reviews the factors which influence the fatigue strength of low alloy steel threaded fasteners, identifies those most significant to fatigue strength, and provides design guidelines based on the direct evaluation of fatigue tests of threaded fasteners. Influences on fatigue strength of thread manufacturing process (machining and rolling of threads), effect of fastener membrane and bending stresses, thread root radii, fastener sizes, fastener tensile strength, stress relaxation, mean stress, and test temperature are discussed.

Skochko, G. W.; Herrmann, T. P.

1992-11-01

139

The character strengths of class clowns  

PubMed Central

Class clowns traditionally were studied as a type concept and identified via sociometric procedures. In the present study a variable-centered approach was favored and class clown behaviors were studied in the context of character strengths, orientations to happiness and satisfaction with life. A sample of 672 Swiss children and adolescents filled in an 18 item self-report instrument depicting class clown behaviors. A hierarchical model of class clown behaviors was developed distinguishing a general factor and the four positively correlated dimensions of “identified as a class clown,” “comic talent,” “disruptive rule-breaker,” and “subversive joker.” Analysis of the general factor showed that class clowns were primarily male, and tended to be seen as class clowns by the teacher. Analyses of the 24 character strengths of the VIA-Youth (Park and Peterson, 2006) showed that class clowns were high in humor and leadership, and low in strengths like prudence, self-regulation, modesty, honesty, fairness, perseverance, and love of learning. An inspection of signature strengths revealed that 75% of class clowns had humor as a signature strength. Furthermore, class clown behaviors were generally shown by students indulging in a life of pleasure, but low life of engagement. The four dimensions yielded different character strengths profiles. While all dimensions of class clowns behaviors were low in temperance strengths, the factors “identified as the class clown” and “comic talent” were correlated with leadership strengths and the two negative factors (“disruptive rule-breaker,” “subversive joker”) were low in other directed strengths. The disruptive rule breaking class clown was additionally low in intellectual strengths. While humor predicted life satisfaction, class clowning tended to go along with diminished satisfaction with life. It is concluded that different types of class clowns need to be kept apart and need different attention by teachers. PMID:25324796

Ruch, Willibald; Platt, Tracey; Hofmann, Jennifer

2014-01-01

140

The character strengths of class clowns.  

PubMed

Class clowns traditionally were studied as a type concept and identified via sociometric procedures. In the present study a variable-centered approach was favored and class clown behaviors were studied in the context of character strengths, orientations to happiness and satisfaction with life. A sample of 672 Swiss children and adolescents filled in an 18 item self-report instrument depicting class clown behaviors. A hierarchical model of class clown behaviors was developed distinguishing a general factor and the four positively correlated dimensions of "identified as a class clown," "comic talent," "disruptive rule-breaker," and "subversive joker." Analysis of the general factor showed that class clowns were primarily male, and tended to be seen as class clowns by the teacher. Analyses of the 24 character strengths of the VIA-Youth (Park and Peterson, 2006) showed that class clowns were high in humor and leadership, and low in strengths like prudence, self-regulation, modesty, honesty, fairness, perseverance, and love of learning. An inspection of signature strengths revealed that 75% of class clowns had humor as a signature strength. Furthermore, class clown behaviors were generally shown by students indulging in a life of pleasure, but low life of engagement. The four dimensions yielded different character strengths profiles. While all dimensions of class clowns behaviors were low in temperance strengths, the factors "identified as the class clown" and "comic talent" were correlated with leadership strengths and the two negative factors ("disruptive rule-breaker," "subversive joker") were low in other directed strengths. The disruptive rule breaking class clown was additionally low in intellectual strengths. While humor predicted life satisfaction, class clowning tended to go along with diminished satisfaction with life. It is concluded that different types of class clowns need to be kept apart and need different attention by teachers. PMID:25324796

Ruch, Willibald; Platt, Tracey; Hofmann, Jennifer

2014-01-01

141

Neural network analysis of strength and ductility of welding alloys for high strength low  

E-print Network

Neural network analysis of strength and ductility of welding alloys for high strength low alloy There are considerable demands for the development of weld metals for high strength low alloy steels. To assist in meeting such demands, a neural network was trained and tested on a set of data obtained on weld metals

Cambridge, University of

142

Practical Estimates of Tensile Strength and Hoek-Brown Strength Parameter m i of Brittle Rocks  

Microsoft Academic Search

By applying the Griffith stress criterion of brittle failure, one can find that the uniaxial compressive strength (sigmac) of rocks is eight times the value of the uniaxial tensile strength (sigmat). The Griffith strength ratio is smaller than what is normally measured for rocks, even with the consideration of crack closure. The reason is that Griffith's theories address only the

M. Cai

2010-01-01

143

A developmental timer regulates degradation of cyclin E1 at the midblastula transition during Xenopus embryogenesis.  

PubMed Central

We have analyzed cyclin E1, a protein that is essential for the G1/S transition, during early development in Xenopus embryos. Cyclin E1 was found to be abundant in eggs, and after fertilization, until the midblastula transition (MBT) when levels of cyclin E1 protein, and associated kinase activity, were found to decline precipitously. Our results suggest that the reduced level of the cyclin E1 protein detected after the MBT does not occur indirectly as a result of degradation of the maternally encoded cyclin E1 mRNA. Instead, the stability of cyclin E1 protein appears to play a major role in reduction of cyclin E1 levels at this time. Cyclin E1 protein was found to be stable during the cleavage divisions but degraded with a much shorter half-life after the MBT. Activation of cyclin E1 protein turnover occurs independent of cell cycle progression, does not require ongoing protein synthesis, and is not triggered as a result of the ratio of nuclei to cytoplasm in embryonic cells that initiates the MBT. We therefore propose that a developmental timing mechanism measures an approximately 5-hr time period, from the time of fertilization, and then allows activation of a protein degradative pathway that regulates cyclin E1. Characterization of the timer suggests that it might be held inactive in eggs by a mitogen-activated protein kinase signal transduction pathway. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 PMID:8700885

Howe, J A; Newport, J W

1996-01-01

144

Geometry and gravity influences on strength capability  

NASA Technical Reports Server (NTRS)

Strength, defined as the capability of an individual to produce an external force, is one of the most important determining characteristics of human performance. Knowledge of strength capabilities of a group of individuals can be applied to designing equipment and workplaces, planning procedures and tasks, and training individuals. In the manned space program, with the high risk and cost associated with spaceflight, information pertaining to human performance is important to ensuring mission success and safety. Knowledge of individual's strength capabilities in weightlessness is of interest within many areas of NASA, including workplace design, tool development, and mission planning. The weightless environment of space places the human body in a completely different context. Astronauts perform a variety of manual tasks while in orbit. Their ability to perform these tasks is partly determined by their strength capability as demanded by that particular task. Thus, an important step in task planning, development, and evaluation is to determine the ability of the humans performing it. This can be accomplished by utilizing quantitative techniques to develop a database of human strength capabilities in weightlessness. Furthermore, if strength characteristics are known, equipment and tools can be built to optimize the operators' performance. This study examined strength in performing a simple task, specifically, using a tool to apply a torque to a fixture.

Poliner, Jeffrey; Wilmington, Robert P.; Klute, Glenn K.

1994-01-01

145

Method and apparatus for determining tensile strength  

DOEpatents

A method and apparatus for determining the statistical distribution of apparent tensile strength of rock, the size effect with respect to tensile strength, as well as apparent deformation modulus of both intact and fractured or jointed rock. The method is carried out by inserting a plug of deformable material, such as rubber, in an opening of a specimen to be tested. The deformable material is loaded by an upper and lower platen until the specimen ruptures, whereafter the tensile strength is calculated based on the parameters of the test specimen and apparatus.

Ratigan, Joe L. (Rapid City, SD)

1984-01-01

146

Modeling strength data for CREW CHIEF  

NASA Technical Reports Server (NTRS)

The Air Force has developed CREW CHIEF, a computer-aided design (CAD) tool for simulating and evaluating aircraft maintenance to determine if the required activities are feasible. CREW CHIEF gives the designer the ability to simulate maintenance activities with respect to reach, accessibility, strength, hand tool operation, and materials handling. While developing the CREW CHIEF, extensive research was performed to describe workers strength capabilities for using hand tools and manual handling of objects. More than 100,000 strength measures were collected and modeled for CREW CHIEF. These measures involved both male and female subjects in the 12 maintenance postures included in CREW CHIEF. The data collection and modeling effort are described.

Mcdaniel, Joe W.

1990-01-01

147

Obi-Wan Adobe: Engineering for Strength  

NSDL National Science Digital Library

Students conduct an experiment to determine how varying the composition of a construction material affects its strength. They make several adobe bricks with differing percentages of sand, soil, fibrous material and water. They test the bricks for strength by dropping them onto a concrete surface from progressively greater heights. Students graph the experiment results and use what they learn to design their own special mix that maximizes the bricks' strength. During the course of the experiment, students learn about variables (independent, dependent, control) and the steps of the engineering design process.

Integrated Teaching And Learning Program

148

Critical role of cytochrome P450 2E1 (CYP2E1) in the development of high fat-induced nonalcoholic steatohepatitis  

PubMed Central

Background & Aims Ethanol-inducible cytochrome P450 2E1 (CYP2E1) activity contributes to oxidative stress. However, CYP2E1 may have an important role in the pathogenesis of high-fat mediated nonalcoholic steatohepatitis (NASH). Thus, the role of CYP2E1 in high-fat mediated NASH development was evaluated. Methods Male wild-type (WT) and Cyp2e1-null mice were fed a low-fat diet (LFD, 10% energy-derived) or high-fat diet (HFD, 60% energy-derived) for 10 weeks. Liver histology and tissue homogenates were examined for various parameters of oxidative stress and inflammation. Results Liver histology showed that only WT mice fed a HFD developed NASH despite increased steatosis in both WT and Cyp2e1-null mice fed HFD. Markers of oxidative stress such as elevated CYP2E1 activity and protein amounts, lipid peroxidation, protein carbonylation, nitration, and glycation with increased phospho-JNK were all markedly elevated only in the livers of HFD-fed WT mice. Furthermore, while the levels of inflammation markers osteopontin and F4/80 were higher in HFD-fed WT mice, TNF? and MCP-1 contents were lower compared to the corresponding LFD-fed WT. Finally, only HFD-fed WT mice exhibited increased insulin resistance and impaired glucose tolerance. Conclusions These data suggest that CYP2E1 is critically important in NASH development by promoting oxidative/nitrosative stress, protein modifications, inflammation and insulin resistance. PMID:22668639

Abdelmegeed, Mohamed A.; Banerjee, Atrayee; Yoo, Seong-Ho; Jang, Sehwan; Gonzalez, Frank J.; Song, Byoung-Joon

2012-01-01

149

Systematics of low-lying E1 and M1 excitations in heavy nuclei from photon scattering experiments  

NASA Astrophysics Data System (ADS)

The results of systematic nuclear resonance fluorescence experiments on heavy deformed and spherical nuclei at the bremsstrahlung facility of the Stuttgart Dynamitron accelerator are reported. The investigation of the fragmentation of the orbital M1 scissors mode in deformed odd-mass nuclei has been continued with high-precision measurements on 166Ho and 163Dy, revealing a lot of weak excitations distributed over the energy range 1.5-4 MeV. The investigation of the (2+?3-) two-phonon excitations in the Sn isotopic chain shows a very harmonic coupling of the phonons. The results for both, the even-even and the odd-mass Sn isotopes are in good agreement with QPM calculations.

Pitz, H. H.; Bauwens, F.; Belic, D.; Bryssinck, J.; von Brentano, P.; Fransen, C.; De Frenne, D.; Govor, L.; Herzberg, R.-D.; Jacobs, E.; Kneissl, U.; Kohstall, C.; Linnemann, A.; Maser, H.; Matschinsky, P.; Nord, A.; Pietralla, N.; Ponomarev, V. Yu.; Scheck, M.; Stedile, F.; Werner, V.

2000-07-01

150

Improved plant-based production of E1 endoglucanase using potato: expression optimization and tissue targeting  

Microsoft Academic Search

Optimization of Acidothermus cellulolyticus endoglucanase (E1) gene expression in transgenic potato (Solanum tuberosum L.) was examined in this study, where the E1 coding sequence was transcribed under control of a leaf specific promoter (tomato RbcS-3C) or the Mac promoter (a hybrid promoter of mannopine synthase promoter and cauliflower mosaic virus 35S promoter enhancer region). Average E1 activity in leaf extracts

Ziyu Dai; Brian S. Hooker; Daniel B. Anderson; Steven R. Thomas

2000-01-01

151

Nutritional Supplements for Strength Power Athletes  

NASA Astrophysics Data System (ADS)

Over the last decade research involving nutritional supplementation and sport performance has increased substantially. Strength and power athletes have specific needs to optimize their performance. Nutritional supplementation cannot be viewed as a replacement for a balanced diet but as an important addition to it. However, diet and supplementation are not mutually exclusive, nor does one depend on the other. Strength and power athletes have four general areas of supplementation needs. First, strength athletes need supplements that have a direct effect on performance. The second group of supplements includes those that promote recovery. The third group comprises the supplements that enhance immune function. The last group of supplements includes those that provide energy or have a direct effect on the workout. This chapter reviews the key supplements needed to optimize the performance and training of the strength athlete.

Wilborn, Colin

152

Crew Strength Training - Duration: 2:56.  

NASA Video Gallery

Train to develop your upper and lower body strength in your muscles and bones by performing body-weight squats and push-ups.The Train Like an Astronaut project uses the excitement of exploration to...

153

On the nature of spall strength  

NASA Astrophysics Data System (ADS)

The nature of spall strength during dynamic loading is considered. The spall strength is shown not to be a material constant. When a primary pulse of duration t moves at velocity c, any fracture event is bounded by a strained layer of thickness s ? ct. In this case, elastic displacement u transforms into irreversible plastic opening ? ? u. The fields of ?f( t) are determined for structureless, plastic, and grain-boundary spallation. The theoretical strength ?f/ E ? 0.1 can be approached during mirror fracture in strong shock waves. When the spall strength is lower by several orders of magnitude, the spallation microrelief is rough and the structural processes characteristic of static fracture are also revealed.

Shtremel', M. A.

2014-04-01

154

High strength concrete provides joint protection  

SciTech Connect

This paper reports on a joint fill material applied on the 24-in. pipe used by Iroquois Gas Transmission Project for its 26-mile Long Island Sound crossing which provides effective joint protection. The 3.35-in. joint fill, made of high instant strength concrete, met stringent requirements for both strength and weight coating, and is environmentally clean to protect the sensitive marine ecosystem. The offshore section, from Bridgeport, Conn., to Long Island, was laid by McDermott, Inc. The high instant strength concrete supplied joint strength and protection during the laying operation, and on the barge itself, where pipe joints are most vulnerable to damage. With joint fill density the same as the concrete already on the pipe, the submerged weight was uniform along the entire length of the marine line, for an essentially seamless coating.

Pool, P. (Offshore Joint Services, Houston, TX (US))

1991-12-01

155

[Muscular strength: an indicator of nutritional status].  

PubMed

A hand dynamometer was used to measure muscle strength in 207 patients admitted to the Gastroenterology service of a general hospital. Validation of international standards in a normal population of both sexes and different ages revealed that our normals perform at the 25% percentile of international values. Results were correlated with other measurements of nutritional status, namely anthropometric measurements, serum albumin level and tuberculin test. Compared to normals, muscle strength was significantly (p < 0.01) lower in patients with body mass index under 19, cutaneous tricipital folding < 85%, brachial circumference < 85%, and serum albumin < 3.5 g/dl. No difference in muscle strength between tuberculin positive or negative subjects was observed. None of the nutritional parameter was helpful to predict complications in patients submitted to surgery. Thus, muscle strength is a useful parameter to evaluate nutritional status but, similar to other measurements, is not predictive of surgical complications. PMID:1341789

Hirsch, S; de la Maza, M P; Obaldía, N; Espinoza, J; Hübner, C; Petermann, M; Bunout, D

1992-06-01

156

Multiscale strength homogenization : application to shale nanoindentation  

E-print Network

Shales are one of the most encountered materials in sedimentary basins. Because of their highly heterogeneous nature, their strength prediction for oil and gas exploitation engineering has long time been an enigma. In this ...

Gathier, Benjamin

2008-01-01

157

Fatigue Strength of Airplane and Engine Materials  

NASA Technical Reports Server (NTRS)

This report was undertaken to give a brief summary of the laws governing the fatigue stresses and of the most important strength coefficients necessary for the correct dimensioning of the structural members.

Matthaes, Kurt

1934-01-01

158

7 CFR 29.2555 - Strength.  

Code of Federal Regulations, 2011 CFR

...REGULATIONS TOBACCO INSPECTION Standards Official Standard Grades for Kentucky and Tennessee Fire-Cured and Foreign-Grown Fire-Cured Tobacco (u.s. Types 22, 23, and Foreign Type 96) § 29.2555 Strength. The stress a...

2011-01-01

159

7 CFR 29.2555 - Strength.  

Code of Federal Regulations, 2010 CFR

...REGULATIONS TOBACCO INSPECTION Standards Official Standard Grades for Kentucky and Tennessee Fire-Cured and Foreign-Grown Fire-Cured Tobacco (u.s. Types 22, 23, and Foreign Type 96) § 29.2555 Strength. The stress a...

2010-01-01

160

Methodology to assay CYP2E1 mixed function oxidase catalytic activity and its induction  

PubMed Central

The cytochrome P450 mixed function oxidase enzymes are the major catalysts involved in drug metabolism. There are many forms of P450. CYP2E1 metabolizes many toxicologically important compounds including ethanol and is active in generating reactive oxygen species. Since several of the contributions in the common theme series “Role of CYP2E1 and Oxidative/Nitrosative Stress in the Hepatotoxic Actions of Alcohol” discuss CYP2E1, this methodology review describes assays on how CYP2E1 catalytic activity and its induction by ethanol and other inducers can be measured using substrate probes such as the oxidation of para-nitrophenol to para-nitrocatechol and the oxidation of ethanol to acetaldehyde. Approaches to validate that a particular reaction e.g. oxidation of a drug or toxin is catalyzed by CYP2E1 or that induction of that reaction is due to induction of CYP2E1 are important and specific examples using inhibitors of CYP2E1, anti-CYP2E1 IgG or CYP2E1 knockout and knockin mice will be discussed. PMID:25454746

Cederbaum, Arthur I.

2014-01-01

161

The measurement of isokinetic fingers flexion strength  

Microsoft Academic Search

Objective. To investigate the feasibility of using isokinetic dynamometry for measuring the dynamic strength of the fingers flexors.Subjects. Sixteen healthy women aged 19–52.Design. Flexion strength was measured isometrically using a Jamar dynamometer and isokinetically using a special attachment which was harnessed to a KinCom 125 dynamometer. In the series comprising the dynamic measurements, the elements of contraction mode (concentric vs

Zeevi Dvir

1997-01-01

162

IMPACT STRENGTH OF GLASS AND GLASS CERAMIC  

SciTech Connect

Strength of glass and glass ceramic was measured with a bar impact technique. High-speed movies show regions of tensile and compressive failure. The borosilicate glass had a compressive strength of at least 2.2 GPa, and the glass ceramic at least 4 GPa. However, the BSG was much stronger in tension than GC. In ballistic tests, the BSG was the superior armor.

Bless, S.; Tolman, J. [Institute for Advanced Technology, University of Texas at Austin, Austin, TX 78759 (United States)

2009-12-28

163

Shoulder Strength After Open Versus Arthroscopic Stabilization  

Microsoft Academic Search

Background: With current techniques, the main difference between arthroscopic and open shoulder stabilization is the violation of the subscapularis tendon. No studies have looked at strength differences of internal and external rotation between these groups.Hypothesis: Internal rotation strength deficits will exist in patients having undergone an open shoulder stabilization procedure compared with an arthroscopic one.Study Design: Piggy-back randomized controlled trial;

Laurie A. Hiemstra; Treny M. Sasyniuk; Nicholas G. H. Mohtadi; Gordon H. Fick

2008-01-01

164

Rayleigh-Taylor Growth with Material Strength  

Microsoft Academic Search

We compare the theory of steady-state Rayleigh-Taylor growth with material strength with 2-D hydrodynamic simulations and experiments on the Omega laser at LLE, U. Rochester. There is both a critical wavelength below which perturbations do not grow, and a critical initial amplitude below which perturbations do not grow. Because material strength makes a difference only at shorter wavelengths, our experiments

Stephen Pollaine; Bruce Remington; Thomas Lorenz; John Edwards; Jeff Colvin; Karnig Mikaelian

2002-01-01

165

Enhancement of dielectric strength in nanocomposites  

SciTech Connect

In this Letter, we report the dielectric breakdown properties of a nano-composite, which is a potential electrical insulation material for cryogenic high voltage applications. The material is composed of a high molecular weight polyvinyl alcohol and nano-sized, {\\em in-situ} fabricated titanate particles. The dielectric breakdown strengths of the filled materials, measured at liquid nitrogen environment, indicate a significant increase of the strength compared to unfilled polyvinyl alcohol. Nanometer sized particles can be adopted as voltage stabilization additive.

Tuncer, Enis [ORNL; Sauers, Isidor [ORNL; James, David Randy [ORNL; Ellis, Alvin R [ORNL; Paranthaman, Mariappan Parans [ORNL; Goyal, Amit [ORNL; More, Karren Leslie [ORNL

2007-01-01

166

Effect of Die Strength and Work Piece Strength on the Wear of Hot Forging Dies  

NASA Astrophysics Data System (ADS)

The effect of the strength ratio extracted from an Archard model for wear is used to describe the wear rates expected in hot forging dies. In the current study, the strength ratio is the strength of the hot forging die to the strength of the work piece. Three hot forging die steels are evaluated. The three die steels are FX, 2714, and WF. To determine the strength of the forging die, a continuous function has been developed that describes the yield strength of three die steels for temperatures from 600 to 700 °C and for times up to 20 h (i.e., tempering times of up to 20 h). The work piece material is assumed to be AISI 1045. Based on the analysis, the wear resistance of WF should be superior and FX should be slightly better than 2714. Decreasing the forging temperature increases the strength ratio, because the strength of the die surface increases faster than the flow strength of AISI 1045. The increase in the strength ratio indicates a decrease in the expected wear rate.

Levy, B. S.; Van Tyne, C. J.

2015-01-01

167

Shear strength of metal-sapphire contacts  

NASA Technical Reports Server (NTRS)

The shear strength of polycrystalline Ag, Cu, Ni, and Fe contacts on clean (0001) sapphire has been studied in ultrahigh vacuum. Both clean metal surfaces and surfaces exposed to O2, Cl2, and C2H4 were used. The results indicate that there are two sources of strength of Al2O3-metal contacts: an intrinsic one that depends on the particular clean metal in contact with Al2O3 and an additional one due to intermediate films. The shear strength of the clean metal contacts correlated directly with the free energy of oxide formation for the lowest metal oxide, in accord with the hypothesis that a chemical bond is formed between metal cations and oxygen anions in the sapphire surface. Contacts formed by metals exposed to chlorine exhibited uniformly low shear strength indicative of van der Waals bonding between chlorinated metal surfaces and sapphire. Contacts formed by metals exposed to oxygen exhibited enhanced shear strength, in accord with the hypothesis that an intermediate oxide layer increases interfacial strength.

Pepper, S. V.

1976-01-01

168

Upper extremity injuries associated with strength training.  

PubMed

Most injuries sustained during strength training are mild strains that resolve with appropriate rest. More severe injuries include traumatic shoulder dislocations, tendon ruptures of the pectoralis major, biceps, and triceps; stress fractures of the distal clavicle, humerus, radius, and ulna; traumatic fractures of the distal radius and ulna in adolescent weightlifters; and compressive and stretch neuropathies. These more severe injuries are usually the result of improperly performing a strength training exercise. Educating athletes regarding proper strength-training techniques serves to reverse established injury patterns and to prevent these injuries in the first place. Recognizing the association of anabolic steroid use to several of the injury patterns further reinforces the need for medical specialists to counsel athletes against their use. With the increasing use of supplements such as creatine, the incidence and nature of strength-training injuries may change further. Greater emphasis on the competitive performance of younger athletes undoubtedly will generate enthusiasm for strength training at earlier ages in both sexes. The importance of proper supervision of these young athletes by knowledgeable persons will increase. As the popularity of strength training grows, there will be ample opportunity to continue to catalog the injury patterns associated with this activity. PMID:11494836

Haupt, H A

2001-07-01

169

[Measuring the handgrip strength of geriatric patients].  

PubMed

The handgrip strength of geriatric patients can be measured when the patient is hospitalized. This article elaborates on the intrinsic and extrinsic factors which have a direct or indirect influence on handgrip strength. For the best results the tests need to be taken in the best circumstances with attention to individual differences and the age of the patient. Handgrip strength as determination of biological vitality is a key concept. Besides the physical characteristics there are many psychological factors (cognition, psyching-up, test attitude…) influencing the results. These are barely mentioned or not mentioned at all in the usual procedures. Research of handgrip strength testing theories is mostly focused on young, healthy adults and less on elderly patients. The main goal of this article is stimulating experimental research on the measurement of handgrip strength with elderly people and involving them more actively with the procedure. It is not enough to acquire insight in function and predicting characteristics of handgrip strength. Next to the aiming for the best test performance is 'working interactively with elderly patients' a goal on itself in the modern vision of health care. PMID:24827615

Kerckhofs, A G M; Vandewoude, M F J; Mudde, A N

2014-09-01

170

Microscopic model for the two-phonon Raman spectra of alkali halides  

NASA Astrophysics Data System (ADS)

The second-order Raman-scattering (SORS) cross section of alkali halides has been evaluated by using the Buckingham expansion for the induced polarizability. This ab initio approach leads to a microscopic expression of the SORS cross section without free parameters. The first two nonzero contributions of the expansion, namely, the dipole-induced dipole (DID) coming from the first-order dressed polarizability and the BTQ (second-dipole hyperpolarizability × dipole propagator × effective charge) coming from the second-dipole-quadrupole polarizability, have been considered. The short-range contribution to the induced polarizability coming from the electronic overlap has not been included in the present work. The SORS spectra are expressed in terms of the dynamical quantities of the crystal (eigenvectors and eigenfrequencies) and in terms of some bare ionic susceptibilities, namely, the ions' bare polarizabilities ?+ and ?- and the second-dipole-quadrupole bare polarizabilities B+ and B-. As an example the results are shown in the case of KBr. Considerations on the long-range nature of the DID spectrum and on the short-range nature of the BTQ spectrum are made. The relative weights of the two contributions to the SORS in the whole class of alkali halides are also discussed.

Gallo, P.; Mazzacurati, V.; Ruocco, G.; Signorelli, G.

1993-05-01

171

Probable Level Densities and Radiative Strength Functions of Dipole gamma-Transitions in 57Fe Compound Nucleus  

E-print Network

From the published results of experimental research of 56Fe(n,2gamma) reaction carried out in Budapest, the values of the most probable densities of cascade intermediate levels with 1/2, 3/2 spin and radiative strength functions of cascade E1 and M1 transitions in 57Fe compound nucleus have been determined. These results correspond to analogous data for other nuclei studied by us and contradict to predictions of conventional models.

A. M. Sukhovoj; V. A. Khitrov; Li Chol; Pham Dinh Khang; Vuong Huu Tan; Nguyen Xuan Hai

2005-08-09

172

Notched Strength Allowables and Inplane Shear Strength of AS4/VRM-34 Textile Laminates  

NASA Technical Reports Server (NTRS)

Notched and unnotched strength allowables were developed for a textile composite to provide input data to analytical structural models based on the Pultruded Rod Stiffened Efficient Unitized Structure (PRSEUS) concept. Filled-hole tensile strength, filled-hole compressive strength, and inplane shear strength along stitch lines have been measured. The material system evaluated in this study is based on warp-knitted preforms of AS4 carbon fibers and VRM-34 epoxy resin, which have been processed via resin infusion and oven curing. All specimens were tested in as-fabricated (dry) condition. Filled-hole strengths were evaluated with and without through-thickness stitching. The effects of scaling on filled-hole tensile strength were evaluated by testing specimens in two widths, but with identical width / hole-diameter ratios. Inplane shear specimens were stitched in two configurations, and two specimen thicknesses were tested for each stitch configuration.

Grenoble, Ray W.; Johnston, William M.

2013-01-01

173

The effect of mineral bond strength and adsorbed water on fault gouge frictional strength  

USGS Publications Warehouse

Recent studies suggest that the tendency of many fault gouge minerals to take on adsorbed or interlayer water may strongly influence their frictional strength. To test this hypothesis, triaxial sliding experiments were conducted on 15 different single-mineral gouges with various water-adsorbing affinities. Vacuum dried samples were sheared at 100 MPa, then saturated with water and sheared farther to compare dry and wet strengths. The coefficients of friction, ?, for the dry sheet-structure minerals (0.2-0.8), were related to mineral bond strength, and dropped 20-60% with the addition of water. For non-adsorbing minerals (? = 0.6-0.8), the strength remained unchanged after saturation. These results confirm that the ability of minerals to adsorb various amounts of water is related to their relative frictional strengths, and may explain the anomalously low strength of certain natural fault gouges.

Morrow, C.A.; Moore, D.E.; Lockner, D.A.

2000-01-01

174

Residual strength of hybrid-fiber-reinforced high-strength concrete after exposure to high temperatures  

Microsoft Academic Search

Residual strengths of high-strength concrete (HSC) and hybrid-fiber-reinforced high-strength concrete (HFRHSC) after exposure to high temperatures were investigated in the paper. The results showed that normal HSC is prone to spalling after exposure to high temperatures, and its first spalling occurs when the temperature approaches 400 °C. For HSC reinforced by high melting point fibers, the first spalling occurs when

Bing Chen; Juanyu Liu

2004-01-01

175

Relation between hand grip strength, respiratory muscle strength and spirometric measures in male nursing home residents.  

PubMed

Adverse-outcomes related to sarcopenia are mostly mentioned as physical disability. As the other skeletal muscles, respiratory muscles may also be affected by sarcopenia. Respiratory muscle strength is known to affect pulmonary functions. Therefore, we aimed to investigate the relations between extremity muscle strength, respiratory muscle strengths and spirometric measures in a group of male nursing home residents. Among a total of 104 male residents, residents with obstructive measures were excluded and final study population was composed of 62 residents. Mean age was 70.5?±?6.7 years, body mass index: 27.7?±?5.3?kg/m2 and dominant hand grip strength: 29.7?±?6.5?kg. Hand grip strength was positively correlated with maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) (r?=?0.35, p?strength; among spirometric measures only parameter significantly related to grip strength was peak cough flow (PCF). The association of PCF with grip strength disappeared when MIP alone or "MIP and MEP" were included in the regression analysis. In the latter case, PCF was significantly associated only with MIP. We found peripheric muscle strength be associated with MIP and PCF but not with MEP or any other spirometric parameters. The relation between peripheral muscle strength and PCF was mediated by MIP. Our findings suggest that sarcopenia may affect inspiratory muscle strength earlier or more than the expiratory muscle strength. Sarcopenia may cause decrease in PCF in the elderly, which may stand for some common adverse respiratory complications. PMID:24993454

Bahat, Gulistan; Tufan, Asli; Ozkaya, Hilal; Tufan, Fatih; Akpinar, Timur Selçuk; Akin, Sibel; Bahat, Zumrut; Kaya, Zuleyha; Kiyan, Esen; Erten, Nilgün; Karan, Mehmet Akif

2014-09-01

176

Practical Estimates of Tensile Strength and Hoek–Brown Strength Parameter m i of Brittle Rocks  

Microsoft Academic Search

By applying the Griffith stress criterion of brittle failure, one can find that the uniaxial compressive strength (?c) of rocks is eight times the value of the uniaxial tensile strength (?t). The Griffith strength ratio is smaller than what is normally measured for rocks, even with the consideration of crack closure.\\u000a The reason is that Griffith’s theories address only the

M. Cai

2010-01-01

177

Influence of mix proportions and curing conditions on tensile splitting strength of high strength concretes  

Microsoft Academic Search

The effect of the composition of high strength concretes with low water to binder ratio and silica fume on the development\\u000a of splitting tensile strength was studied. A statistical approach was employed to develop formulation which could adequately\\u000a describe the relations between splitting tensile strength and the concrete composition, when cured in two different regimes:\\u000a water curing at 20°C and

K. Kovler; I. Schamban; S. Igarashi; A. Bentur

1999-01-01

178

Level densities and radiative strength functions  

NASA Astrophysics Data System (ADS)

This paper presents a summary of the latest results from experiments performed at the Oslo Cyclotron. The Oslo group has developed a technique to extract simultaneously the level density and radiative strength function from primary ?-ray spectra. A small (pygmy) resonance in the radiative strength function has been observed at around 3 MeV in several deformed rare earth nuclei. This resonance is shown to be of M1 character and the origin is thought to be the scissors mode. This resonance vanishes for the spherical Sm nuclei, as expected, since the scissors mode is dependent on deformation. Experiments performed in Oslo found the resonance in Dy isotopes to be twice as wide as the width extracted in an indirect way by comparing simulations with two-step cascade spectra from neutron capture experiments. In 116,117Sn an increase in the slope of the radiative strength function around E? = 4.5 MeV indicates the onset of resonance-like structures in both nuclei, resulting in a significant enhancement of the radiative strength functions compared to standard models in the energy region 4.5strength function below 4 MeV which has been observed in Fe, Mo, V, and Sc isotopes. The level density and radiative strength function of 96Mo have been reanalyzed, and the enhanced ? strength for E?<3-4 MeV is confirmed. This enhancement is presently not understood and remains a challenge for theoretical models.

Siem, S.; Agvaanluvsan, U.; Bü; rger, A.; Guttormsen, M.; Larsen, A. C.; Mitchell, G.; Nyhus, H. T.; Chankova, R.; Rekstad, J.; Schiller, A.; Syed, N. U. H.; Toft, H. K.; Tveten, G. M.; Voinov, A.

2009-01-01

179

Shear Strength Behavior of Human Trabecular Bone  

PubMed Central

The shear strength of human trabecular bone may influence overall bone strength under fall loading conditions and failure at bone-implant interfaces. Here, we sought to compare shear and compressive yield strengths of human trabecular bone and elucidate the underlying failure mechanisms. We analyzed 54 specimens (5-mm cubes), all aligned with the main trabecular orientation and spanning four anatomic sites, 44 different cadavers, and a wide range of bone volume fraction (0.06–0.38). Micro-CT-based non-linear finite element analysis was used to assess the compressive and shear strengths and the spatial distribution of yielded tissue; the tissue-level constitutive model allowed for kinematic non-linearity and yielding with strength asymmetry. We found that the computed values of both the shear and compressive strengths depended on bone volume fraction via power law relations having an exponent of 1.7 (R2=0.95 shear; R2=0.97 compression). The ratio of shear to compressive strengths (mean ± SD, 0.44 ± 0.16) did not depend on bone volume fraction (p=0.24) but did depend on microarchitecture, most notably the intra-trabecular standard deviation in trabecular spacing (R2=0.23, p<0.005). For shear, the main tissue-level failure mode was tensile yield of the obliquely oriented trabeculae. By contrast, for compression, specimens having low bone volume fraction failed primarily by large-deformation-related tensile yield of horizontal trabeculae and those having high bone volume failed primarily by compressive yield of vertical trabeculae. We conclude that human trabecular bone is generally much weaker in shear than compression at the apparent level, reflecting different failure mechanisms at the tissue level. PMID:22884967

Sanyal, Arnav; Gupta, Atul; Bayraktar, Harun H.; Kwon, Ronald Y.; Keaveny, Tony M.

2012-01-01

180

Corticospinal adaptations and strength maintenance in the immobilized arm following 3 weeks unilateral strength training.  

PubMed

Cross-education strength training has being shown to retain strength and muscle thickness in the immobilized contralateral limb. Corticospinal mechanisms have been proposed to underpin this phenomenon; however, no transcranial magnetic stimulation (TMS) data has yet been presented. This study used TMS to measure corticospinal responses following 3 weeks of unilateral arm training on the contralateral, immobilize arm. Participants (n = 28) were randomly divided into either immobilized strength training (Immob + train) immobilized no training (Immob) or control. Participants in the immobilized groups had their nondominant arm rested in a sling, 15 h/day for 3 weeks. The Immob + train group completed unilateral arm curl strength training, while the Immob and control groups did not undertake training. All participants were tested for corticospinal excitability, strength, and muscle thickness of both arms. Immobilization resulted in a group x time significant reduction in strength, muscle thickness and corticospinal excitability for the untrained limb of the Immob group. Conversely, no significant change in strength, muscle thickness, or corticospinal excitability occurred in the untrained limb of the Immob + train group. These results provide the first evidence of corticospinal mechanisms, assessed by TMS, underpinning the use of unilateral strength training to retain strength and muscle thickness following immobilization of the contralateral limb. PMID:22429184

Pearce, A J; Hendy, A; Bowen, W A; Kidgell, D J

2013-12-01

181

49 CFR 230.28 - Higher shearing strength of rivets.  

Code of Federal Regulations, 2010 CFR

...DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Boilers and Appurtenances Strength of Materials § 230.28 Higher shearing strength of rivets. A higher shearing strength may be used for rivets when...

2010-10-01

182

49 CFR 230.26 - Tensile strength of shell plates.  

Code of Federal Regulations, 2010 CFR

...DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Boilers and Appurtenances Strength of Materials § 230.26 Tensile strength of shell plates. When the tensile strength of steel or wrought-iron shell...

2010-10-01

183

49 CFR 230.27 - Maximum shearing strength of rivets.  

Code of Federal Regulations, 2010 CFR

...DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Boilers and Appurtenances Strength of Materials § 230.27 Maximum shearing strength of rivets. The maximum shearing strength of rivets per square...

2010-10-01

184

30 CFR 75.1431 - Minimum rope strength.  

Code of Federal Regulations, 2010 CFR

...STANDARDS-UNDERGROUND COAL MINES Hoisting and Mantrips Wire Ropes § 75.1431 Minimum rope strength. At installation, the nominal strength...manufacturer's published catalog strength) of wire ropes used for hoisting shall meet the minimum rope...

2010-07-01

185

30 CFR 56.19021 - Minimum rope strength.  

Code of Federal Regulations, 2013 CFR

...METAL AND NONMETAL MINES Personnel Hoisting Wire Ropes § 56.19021 Minimum rope strength. At installation, the nominal strength...manufacturer's published catalog strength) of wire ropes used for hoisting shall meet the minimum rope...

2013-07-01

186

30 CFR 75.1431 - Minimum rope strength.  

Code of Federal Regulations, 2011 CFR

...STANDARDS-UNDERGROUND COAL MINES Hoisting and Mantrips Wire Ropes § 75.1431 Minimum rope strength. At installation, the nominal strength...manufacturer's published catalog strength) of wire ropes used for hoisting shall meet the minimum rope...

2011-07-01

187

30 CFR 57.19021 - Minimum rope strength.  

Code of Federal Regulations, 2011 CFR

...METAL AND NONMETAL MINES Personnel Hoisting Wire Ropes § 57.19021 Minimum rope strength. At installation, the nominal strength...manufacturer's published catalog strength) of wire ropes used for hoisting shall meet the minimum rope...

2011-07-01

188

30 CFR 57.19021 - Minimum rope strength.  

Code of Federal Regulations, 2012 CFR

...METAL AND NONMETAL MINES Personnel Hoisting Wire Ropes § 57.19021 Minimum rope strength. At installation, the nominal strength...manufacturer's published catalog strength) of wire ropes used for hoisting shall meet the minimum rope...

2012-07-01

189

30 CFR 56.19021 - Minimum rope strength.  

Code of Federal Regulations, 2010 CFR

...METAL AND NONMETAL MINES Personnel Hoisting Wire Ropes § 56.19021 Minimum rope strength. At installation, the nominal strength...manufacturer's published catalog strength) of wire ropes used for hoisting shall meet the minimum rope...

2010-07-01

190

30 CFR 56.19021 - Minimum rope strength.  

Code of Federal Regulations, 2011 CFR

...METAL AND NONMETAL MINES Personnel Hoisting Wire Ropes § 56.19021 Minimum rope strength. At installation, the nominal strength...manufacturer's published catalog strength) of wire ropes used for hoisting shall meet the minimum rope...

2011-07-01

191

30 CFR 57.19021 - Minimum rope strength.  

Code of Federal Regulations, 2013 CFR

...METAL AND NONMETAL MINES Personnel Hoisting Wire Ropes § 57.19021 Minimum rope strength. At installation, the nominal strength...manufacturer's published catalog strength) of wire ropes used for hoisting shall meet the minimum rope...

2013-07-01

192

30 CFR 56.19021 - Minimum rope strength.  

Code of Federal Regulations, 2014 CFR

...METAL AND NONMETAL MINES Personnel Hoisting Wire Ropes § 56.19021 Minimum rope strength. At installation, the nominal strength...manufacturer's published catalog strength) of wire ropes used for hoisting shall meet the minimum rope...

2014-07-01

193

30 CFR 77.1431 - Minimum rope strength.  

Code of Federal Regulations, 2012 CFR

...UNDERGROUND COAL MINES Personnel Hoisting Wire Ropes § 77.1431 Minimum rope strength. At installation, the nominal strength...manufacturer's published catalog strength) of wire ropes used for hoisting shall meet the minimum rope...

2012-07-01

194

30 CFR 75.1431 - Minimum rope strength.  

Code of Federal Regulations, 2014 CFR

...STANDARDS-UNDERGROUND COAL MINES Hoisting and Mantrips Wire Ropes § 75.1431 Minimum rope strength. At installation, the nominal strength...manufacturer's published catalog strength) of wire ropes used for hoisting shall meet the minimum rope...

2014-07-01

195

30 CFR 77.1431 - Minimum rope strength.  

Code of Federal Regulations, 2013 CFR

...UNDERGROUND COAL MINES Personnel Hoisting Wire Ropes § 77.1431 Minimum rope strength. At installation, the nominal strength...manufacturer's published catalog strength) of wire ropes used for hoisting shall meet the minimum rope...

2013-07-01

196

30 CFR 77.1431 - Minimum rope strength.  

Code of Federal Regulations, 2011 CFR

...UNDERGROUND COAL MINES Personnel Hoisting Wire Ropes § 77.1431 Minimum rope strength. At installation, the nominal strength...manufacturer's published catalog strength) of wire ropes used for hoisting shall meet the minimum rope...

2011-07-01

197

30 CFR 56.19021 - Minimum rope strength.  

Code of Federal Regulations, 2012 CFR

...METAL AND NONMETAL MINES Personnel Hoisting Wire Ropes § 56.19021 Minimum rope strength. At installation, the nominal strength...manufacturer's published catalog strength) of wire ropes used for hoisting shall meet the minimum rope...

2012-07-01

198

30 CFR 57.19021 - Minimum rope strength.  

Code of Federal Regulations, 2014 CFR

...METAL AND NONMETAL MINES Personnel Hoisting Wire Ropes § 57.19021 Minimum rope strength. At installation, the nominal strength...manufacturer's published catalog strength) of wire ropes used for hoisting shall meet the minimum rope...

2014-07-01

199

30 CFR 57.19021 - Minimum rope strength.  

Code of Federal Regulations, 2010 CFR

...METAL AND NONMETAL MINES Personnel Hoisting Wire Ropes § 57.19021 Minimum rope strength. At installation, the nominal strength...manufacturer's published catalog strength) of wire ropes used for hoisting shall meet the minimum rope...

2010-07-01

200

30 CFR 75.1431 - Minimum rope strength.  

Code of Federal Regulations, 2012 CFR

...STANDARDS-UNDERGROUND COAL MINES Hoisting and Mantrips Wire Ropes § 75.1431 Minimum rope strength. At installation, the nominal strength...manufacturer's published catalog strength) of wire ropes used for hoisting shall meet the minimum rope...

2012-07-01

201

30 CFR 75.1431 - Minimum rope strength.  

Code of Federal Regulations, 2013 CFR

...STANDARDS-UNDERGROUND COAL MINES Hoisting and Mantrips Wire Ropes § 75.1431 Minimum rope strength. At installation, the nominal strength...manufacturer's published catalog strength) of wire ropes used for hoisting shall meet the minimum rope...

2013-07-01

202

30 CFR 77.1431 - Minimum rope strength.  

Code of Federal Regulations, 2014 CFR

...UNDERGROUND COAL MINES Personnel Hoisting Wire Ropes § 77.1431 Minimum rope strength. At installation, the nominal strength...manufacturer's published catalog strength) of wire ropes used for hoisting shall meet the minimum rope...

2014-07-01

203

30 CFR 77.1431 - Minimum rope strength.  

Code of Federal Regulations, 2010 CFR

...UNDERGROUND COAL MINES Personnel Hoisting Wire Ropes § 77.1431 Minimum rope strength. At installation, the nominal strength...manufacturer's published catalog strength) of wire ropes used for hoisting shall meet the minimum rope...

2010-07-01

204

High-Strength Bolt Corrosion Fatigue Life Model and Application  

PubMed Central

The corrosion fatigue performance of high-strength bolt was studied. Based on the fracture mechanics theory and the Gerberich-Chen formula, the high-strength bolt corrosion fracture crack model and the fatigue life model were established. The high-strength bolt crack depth and the fatigue life under corrosion environment were quantitatively analyzed. The factors affecting high-strength bolt corrosion fatigue life were discussed. The result showed that the high-strength bolt corrosion fracture biggest crack depth reduces along with the material yield strength and the applied stress increases. The material yield strength was the major factor. And the high-strength bolt corrosion fatigue life reduced along with the increase of material strength, the applied stress or stress amplitude. The stress amplitude influenced the most, and the material yield strength influenced the least. Low bolt strength and a low stress amplitude level could extend high-strength bolt corrosion fatigue life. PMID:25152916

Hui-li, Wang; Si-feng, Qin

2014-01-01

205

78 FR 15597 - Special Conditions: GE Aviation CT7-2E1 Turboshaft Engine Model  

Federal Register 2010, 2011, 2012, 2013, 2014

...regulations in effect on the date of...the GE CT7-2E1 engine model is up to...CT7-2E1 turboshaft engine model meets the...regulations in effect on the date of...representative installation of the engine when...

2013-03-12

206

Oxidative stress mediated toxicity exerted by ethanol-inducible CYP2E1  

SciTech Connect

Induction of CYP2E1 by ethanol is one of the central pathways by which ethanol generates a state of oxidative stress in hepatocytes. To study the biochemical and toxicological actions of CYP2E1, our laboratory established HepG2 cell lines which constitutively overexpress CYP2E1 and characterized these cells with respect to ethanol toxicity. Addition of ethanol or an unsaturated fatty acid such as arachidonic acid or iron was toxic to the CYP2E1-expressing cells but not control cells. This toxicity was associated with elevated lipid peroxidation and could be prevented by antioxidants and inhibitors of CYP2E1. Apoptosis occurred in the CYP2E1-expressing cells exposed to ethanol, arachidonic acid, or iron. Removal of GSH caused a loss of viability in the CYP2E1-expressing cells even in the absence of added toxin or pro-oxidant. This was associated with mitochondrial damage and decreased mitochondrial membrane potential. Low concentrations of iron and arachidonic acid synergistically interacted with CYP2E1 to produce cell toxicity, suggesting these nutrients may act as priming or sensitizing agents to alcohol-induced liver injury. Surprisingly, CYP2E1-expressing cells had elevated GSH levels, due to transcriptional activation of glutamate cysteine ligase. Similarly, levels of catalase, alpha-, and microsomal glutathione transferase were also increased, suggesting that upregulation of these antioxidant genes may reflect an adaptive mechanism to remove CYP2E1-derived oxidants. Using co-cultures, interaction between CYP2E1-derived diffusible mediators to activate collagen production in hepatic stellate cells was found. While it is likely that several mechanisms contribute to alcohol-induced liver injury, the linkage between CYP2E1-dependent oxidative stress, mitochondrial injury, stellate cell activation, and GSH homeostasis may contribute to the toxic action of ethanol on the liver. HepG2 cell lines overexpressing CYP2E1 may be a valuable model to characterize the biochemical and toxicological properties of CYP2E1.

Wu Defeng [Department of Pharmacology and Biological Chemistry, Box 1603, Mount Sinai School of Medicine, One Gustave L. Levy Place, New York, NY 10029 (United States); Cederbaum, Arthur I. [Department of Pharmacology and Biological Chemistry, Box 1603, Mount Sinai School of Medicine, One Gustave L. Levy Place, New York, NY 10029 (United States)]. E-mail: arthur.cederbaum@mssm.edu

2005-09-01

207

Distinct Features of Cap Binding by eIF4E1b Proteins  

PubMed Central

eIF4E1b, closely related to the canonical translation initiation factor 4E (eIF4E1a), cap-binding protein is highly expressed in mouse, Xenopus and zebrafish oocytes. We have previously characterized eIF4E1b as a component of the CPEB mRNP translation repressor complex along with the eIF4E-binding protein 4E-Transporter, the Xp54/DDX6 RNA helicase and additional RNA-binding proteins. eIF4E1b exhibited only very weak interactions with m7GTP-Sepharose and, rather than binding eIF4G, interacted with 4E-T. Here we undertook a detailed examination of both Xenopus and human eIF4E1b interactions with cap analogues using fluorescence titration and homology modeling. The predicted structure of eIF4E1b maintains the ? + ? fold characteristic of eIF4E proteins and its cap-binding pocket is similarly arranged by critical amino acids: Trp56, Trp102, Glu103, Trp166, Arg112, Arg157 and Lys162 and residues of the C-terminal loop. However, we demonstrate that eIF4E1b is 3-fold less well able to bind the cap than eIF4E1a, both proteins being highly stimulated by methylation at N7 of guanine. Moreover, eIF4E1b proteins are distinguishable from eIF4E1a by a set of conserved amino acid substitutions, several of which are located near to cap-binding residues. Indeed, eIF4E1b possesses several distinct features, namely, enhancement of cap binding by a benzyl group at N7 position of guanine, a reduced response to increasing length of the phosphate chain and increased binding to a cap separated by a linker from Sepharose, suggesting differences in the arrangement of the protein's core. In agreement, mutagenesis of the amino acids differentiating eIF4E1b from eIF4E1a reduces cap binding by eIF4E1a 2-fold, demonstrating their role in modulating cap binding. PMID:25463438

Kubacka, Dorota; Miguel, Ricardo Núñez; Minshall, Nicola; Darzynkiewicz, Edward; Standart, Nancy; Zuberek, Joanna

2015-01-01

208

Distinct Features of Cap Binding by eIF4E1b Proteins.  

PubMed

eIF4E1b, closely related to the canonical translation initiation factor 4E (eIF4E1a), cap-binding protein is highly expressed in mouse, Xenopus and zebrafish oocytes. We have previously characterized eIF4E1b as a component of the CPEB mRNP translation repressor complex along with the eIF4E-binding protein 4E-Transporter, the Xp54/DDX6 RNA helicase and additional RNA-binding proteins. eIF4E1b exhibited only very weak interactions with m(7)GTP-Sepharose and, rather than binding eIF4G, interacted with 4E-T. Here we undertook a detailed examination of both Xenopus and human eIF4E1b interactions with cap analogues using fluorescence titration and homology modeling. The predicted structure of eIF4E1b maintains the ?+? fold characteristic of eIF4E proteins and its cap-binding pocket is similarly arranged by critical amino acids: Trp56, Trp102, Glu103, Trp166, Arg112, Arg157 and Lys162 and residues of the C-terminal loop. However, we demonstrate that eIF4E1b is 3-fold less well able to bind the cap than eIF4E1a, both proteins being highly stimulated by methylation at N(7) of guanine. Moreover, eIF4E1b proteins are distinguishable from eIF4E1a by a set of conserved amino acid substitutions, several of which are located near to cap-binding residues. Indeed, eIF4E1b possesses several distinct features, namely, enhancement of cap binding by a benzyl group at N(7) position of guanine, a reduced response to increasing length of the phosphate chain and increased binding to a cap separated by a linker from Sepharose, suggesting differences in the arrangement of the protein's core. In agreement, mutagenesis of the amino acids differentiating eIF4E1b from eIF4E1a reduces cap binding by eIF4E1a 2-fold, demonstrating their role in modulating cap binding. PMID:25463438

Kubacka, Dorota; Miguel, Ricardo Núñez; Minshall, Nicola; Darzynkiewicz, Edward; Standart, Nancy; Zuberek, Joanna

2015-01-30

209

?-? stacking, spin density and magnetic coupling strength.  

PubMed

The ?-? stacking interaction, one of the main intermolecular forces, sometimes leads to amazing magnetic properties. Although the concept has been raised that spin density is one of the main factors that contribute to the magnetic coupling strength in intermolecular magnetic coupling systems, it has not been confirmed either experimentally or theoretically to date. Herein we present a study on the magnetostructural data of seven unpublished Cu(II) complexes and ten reported radicals. It is confirmed for the first time that the spin density on short contact atoms is a major factor that contributes to the ?-? stacking magnetic coupling strength. Based on the reported data to date, when the short contact distance is larger than the default contact radius, medium or relatively strong magnetic coupling strength could be obtained only if the spin density on the short contact atoms is greater than 0.1350; when the C···C short contact is less than the default contact radius of 3.4 Å, but not less than 3.351 Å, and the spin density is less than 0.1, neither medium nor strong magnetic coupling strength could be observed. Further, when the short contact distance decreases with a temperature drop, the spin densities on the relevant short contact atoms increase. In the complexes reported the small spin densities on the relevant short contact atoms are the major factors that result in the weak ?-? magnetic coupling strength. PMID:24005474

Chi, Yan-Hui; Shi, Jing-Min; Li, Hong-Nan; Wei, Wei; Cottrill, Ethan; Pan, Ning; Chen, Hu; Liang, Yuan; Yu, Li; Zhang, Yi-Quan; Hou, Chao

2013-11-28

210

(Finite) statistical size effects on compressive strength  

PubMed Central

The larger structures are, the lower their mechanical strength. Already discussed by Leonardo da Vinci and Edmé Mariotte several centuries ago, size effects on strength remain of crucial importance in modern engineering for the elaboration of safety regulations in structural design or the extrapolation of laboratory results to geophysical field scales. Under tensile loading, statistical size effects are traditionally modeled with a weakest-link approach. One of its prominent results is a prediction of vanishing strength at large scales that can be quantified in the framework of extreme value statistics. Despite a frequent use outside its range of validity, this approach remains the dominant tool in the field of statistical size effects. Here we focus on compressive failure, which concerns a wide range of geophysical and geotechnical situations. We show on historical and recent experimental data that weakest-link predictions are not obeyed. In particular, the mechanical strength saturates at a nonzero value toward large scales. Accounting explicitly for the elastic interactions between defects during the damage process, we build a formal analogy of compressive failure with the depinning transition of an elastic manifold. This critical transition interpretation naturally entails finite-size scaling laws for the mean strength and its associated variability. Theoretical predictions are in remarkable agreement with measurements reported for various materials such as rocks, ice, coal, or concrete. This formalism, which can also be extended to the flowing instability of granular media under multiaxial compression, has important practical consequences for future design rules. PMID:24733930

Weiss, Jérôme; Girard, Lucas; Gimbert, Florent; Amitrano, David; Vandembroucq, Damien

2014-01-01

211

(Finite) statistical size effects on compressive strength.  

PubMed

The larger structures are, the lower their mechanical strength. Already discussed by Leonardo da Vinci and Edmé Mariotte several centuries ago, size effects on strength remain of crucial importance in modern engineering for the elaboration of safety regulations in structural design or the extrapolation of laboratory results to geophysical field scales. Under tensile loading, statistical size effects are traditionally modeled with a weakest-link approach. One of its prominent results is a prediction of vanishing strength at large scales that can be quantified in the framework of extreme value statistics. Despite a frequent use outside its range of validity, this approach remains the dominant tool in the field of statistical size effects. Here we focus on compressive failure, which concerns a wide range of geophysical and geotechnical situations. We show on historical and recent experimental data that weakest-link predictions are not obeyed. In particular, the mechanical strength saturates at a nonzero value toward large scales. Accounting explicitly for the elastic interactions between defects during the damage process, we build a formal analogy of compressive failure with the depinning transition of an elastic manifold. This critical transition interpretation naturally entails finite-size scaling laws for the mean strength and its associated variability. Theoretical predictions are in remarkable agreement with measurements reported for various materials such as rocks, ice, coal, or concrete. This formalism, which can also be extended to the flowing instability of granular media under multiaxial compression, has important practical consequences for future design rules. PMID:24733930

Weiss, Jérôme; Girard, Lucas; Gimbert, Florent; Amitrano, David; Vandembroucq, Damien

2014-04-29

212

Role of CYP2E1 in thioacetamide-induced mouse hepatotoxicity.  

PubMed

Previous experiments showed that treatment of mice and rats with thioacetamide (TAA) induced liver cell damage, fibrosis and/or cirrhosis, associated with increased oxidative stress and activation of hepatic stellate cells. Some experiments suggest that CYP2E1 may be involved in the metabolic activation of TAA. However, there is no direct evidence on the role of CYP2E1 in TAA-mediated hepatotoxicity. To clarify this, TAA-induced hepatotoxicity was investigated using Cyp2e1-null mice. Male wild-type and Cyp2e1-null mice were treated with TAA (200 mg/kg of body weight, single, i.p.) at 6 weeks of age, and hepatotoxicity examined 24 and 48 h after TAA treatment. Relative liver weights of Cyp2e1-null mice were significantly different at 24 h compared to wild-type mice (p<0.01). Serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) in Cyp2e1-null mice were significantly different at both time points compared to wild-type mice (p<0.01). Histopathological examination showed Cyp2e1-null mice represented no hepatototoxic lesions, in clear contrast to severe centriobular necrosis, inflammation and hemorrhage at both time points in wild-type mice. Marked lipid peroxidation was also only limited to wild-type mice (p<0.01). Similarly, TNF-alpha, IL-6 and glutathione peroxidase mRNA expression in Cyp2e1-null mice did not significantly differ from the control levels, contrasting with the marked alteration in wild-type mice (p<0.01). Western blot analysis further revealed no increase in iNOS expression in Cyp2e1-null mice. These results reveal that CYP2E1 mediates TAA-induced hepatotoxicity in wild-type mice as a result of increased oxidative stress. PMID:18374380

Kang, Jin Seok; Wanibuchi, Hideki; Morimura, Keiichirou; Wongpoomchai, Rawiwan; Chusiri, Yaowares; Gonzalez, Frank J; Fukushima, Shoji

2008-05-01

213

Resveratrol Downregulates Cyp2e1 and Attenuates Chemically Induced Hepatocarcinogenesis in SD Rats  

PubMed Central

Cyp2e1 plays an important role in chemically induced hepatocarcinogenesis. Resveratrol (REV) is known to prevent diethylnitrosamine (DEN)-induced hepatocarcinogenesis, but its effects on this process induced by DEN and 2-acetylaminofluorene (2-AAF) and the role of Cyp2e1 remain unclear. In this study, glutathione S-transferase placental form (GST-P)-positive foci were used as a marker of hepatocarcinogenesis. REV or diallyl disulfide (DADS, an inhibitor of Cyp2e1) significantly reduced both the area and number of GST-P-positive foci induced by DEN and 2-AAF. Treatment with REV or DADS also markedly decreased the expression of Cyp2e1 in the rat liver. By immunohistochemical staining of serial liver sections, we found that the expression of Cyp2e1 in GST-P-positive foci showed three distinct patterns: decreased in GST-P foci, increased in GST-P foci when compared with surrounding liver tissue and mixed type. The number of GST-P foci with increased Cyp2e1 expression was greater than the number of GST-P foci with decreased Cyp2e1. Protein levels of GST-P and Cyp2e1 were also higher in foci compared with surrounding liver tissue. REV or DADS significantly reduced the expression of GST-P and Cyp2e1 in both foci and surrounding liver tissue. Taken together, these results suggested that REV has a significant inhibitory effect on chemically induced hepatocarcinogenesis, which may be attributed to downregulation of Cyp2e1. PMID:24526811

Wu, Xiongfei; Li, Chenggang; Xing, Guozhen; Qi, Xinming; Ren, Jin

2013-01-01

214

Mechanical properties of high-strength concrete  

NASA Astrophysics Data System (ADS)

This report summarizes an experimental program conducted to investigate production techniques and mechanical properties of high strength concrete in general and to provide recommendations for using these concretes in manufacturing precast/prestressed bridge girders. Test variables included total amount and composition of cementitious material (portland cement, fly ash, and silica fume), type and brand of cement, type of silica fume (dry densified and slurry), type and brand of high-range water-reducing admixture, type of aggregate, aggregate gradation, maximum aggregate size, and curing. Tests were conducted to determine the effects of these variables on changes in compressive strength and modulus of elasticity over time, splitting tensile strength, modulus of rupture, creep, shrinkage, and absorption potential (as an indirect indicator of permeability). Also investigated were the effects of test parameters such as mold size, mold material, and end condition. Over 6,300 specimens were cast from approximately 140 mixes over a period of 3 years.

Mokhtarzadeh, Alireza

215

Development of high strength, high temperature ceramics  

NASA Technical Reports Server (NTRS)

Improvement in the high-pressure turbopumps, both fuel and oxidizer, in the Space Shuttle main engine were considered. The operation of these pumps is limited by temperature restrictions of the metallic components used in these pumps. Ceramic materials that retain strength at high temperatures and appear to be promising candidates for use as turbine blades and impellers are discussed. These high strength materials are sensitive to many related processing parameters such as impurities, sintering aids, reaction aids, particle size, processing temperature, and post thermal treatment. The specific objectives of the study were to: (1) identify and define the processing parameters that affect the properties of Si3N4 ceramic materials, (2) design and assembly equipment required for processing high strength ceramics, (3) design and assemble test apparatus for evaluating the high temperature properties of Si3N4, and (4) conduct a research program of manufacturing and evaluating Si3N4 materials as applicable to rocket engine applications.

Hall, W. B.

1982-01-01

216

CHARACTERIZATION OF TENSILE STRENGTH OF GLOVEBOX GLOVES  

SciTech Connect

A task was undertaken to compare various properties of different glovebox gloves, having various compositions, for use in gloveboxes at the Savannah River Site (SRS). One aspect of this project was to determine the tensile strength (TS) of the gloves. Longitudinal tensile samples were cut from 15 different gloves and tensile tested. The stress, load, and elongation at failure were determined. All of the gloves that are approved for glovebox use and listed in the glovebox procurement specification met the tensile and elongation requirements. The Viton{reg_sign} compound gloves are not listed in the specification, but exhibited lower tensile strengths than permissible based on the Butyl rubber requirements. Piercan Polyurethane gloves were the thinnest samples and exhibited the highest tensile strength of the materials tested.

Korinko, P.; Chapman, G.

2012-02-29

217

Strength function under the absorbing boundary condition  

NASA Astrophysics Data System (ADS)

The strength function of the linear response by the external field is calculated in the formalism of the absorbing boundary condition (ABC). The dipole excitation of a schematic two-body system is treated in the present study. The extended completeness relation, which is assumed on the analogy of the formulation in the complex scaling method (CSM), is applied to the calculation of the strength function. The calculation of the strength function is successful in the present formalism and hence, the extended completeness relation seems to work well in the ABC formalism. The contributions from the resonance and the non-resonant continuum is also analyzed according to the decomposition of the energy levels in the extended completeness relation.

Iwasaki, M.; Otani, R.; Ito, M.

2014-12-01

218

U-groove aluminum weld strength improvement  

NASA Technical Reports Server (NTRS)

Though butt-welds are among the most preferred joining methods in aerostructures, their strength dependence on inelastic mechanics is generally the least understood. This study investigated experimental strain distributions across a thick aluminum U-grooved weld and identified two weld process considerations for improving the multipass weld strength. The extreme thermal expansion and contraction gradient of the fusion heat input across the groove tab thickness produces severe peaking which induces bending under uniaxial loading. The filler strain-hardening deceased with increasing filler pass sequence, producing the weakest welds on the last pass side. Current welding schedules unknowingly compound these effects which reduce the weld strength. A de-peaking index model was developed to select filler pass thicknesses, pass numbers, and sequences to improve de-peaking in the welding process. Intent is to combine the strongest weld pass side with the peaking induced bending tension to provide a more uniform stress and stronger weld under axial tensile loading.

Verderaime, V.; Vaughan, R.

1995-01-01

219

U-Groove aluminum weld strength improvement  

NASA Technical Reports Server (NTRS)

Though butt-welds are among the most preferred joining methods in aerostructures, their strength dependence on inelastic mechanics is generally the least understood. This study investigated experimental strain distributions across a thick aluminum U-grooved weld and identified two weld process considerations for improving the multipass weld strength. The extreme thermal expansion and contraction gradient of the fusion heat input across the groove tab thickness produces severe peaking, which induces bending under uniaxial loading. The filler strain-hardening decreased with increasing filler pass sequence, producing the weakest welds on the last pass side. Current welding schedules unknowingly compound these effects which reduce the weld strength. A depeaking index model was developed to select filler pass thicknesses, pass numbers, and sequences to improve depeaking in the welding process. The intent is to combine the strongest weld pass side with the peaking induced bending tension to provide a more uniform stress and stronger weld under axial tensile loading.

Verderaime, V.; Vaughan, R.

1996-01-01

220

Strength and conditioning practices in rowing.  

PubMed

There is limited published research on the practices of strength and conditioning (S &C) coaches in Great Britain. Information about training program design would be useful in developing models of good practice and ecologically valid intervention studies. The aim of this research was to quantify the training practices of coaches responsible for the S&C of rowing athletes. A questionnaire was developed that consisted of 6 sections: (a) personal details, (b) physical testing, (c) strength and power development, (d) flexibility development, (e) unique aspects of the program, and (f) any further relevant comments regarding the athletes prescribed training program. Twenty-two rowing and 10 S&C coaches with an average of 10.5 ± 7.2 years' experience agreed to complete the questionnaire. Approximately, 34% coached rowers of Olympic standard, 34% coached national standard, 3% coached regional standard, 19% coached club standard, and 10% coached university standard rowers. All coaches agreed that strength training enhanced rowing performance and the majority (74%) indicated that athletes' strength trained 2-3 times a week. Almost all coaches (94%) reported their rowers performed strength training, with 81% using Olympic lifting, and 91% employing a periodized training model. The clean (63%) and squat (27%) were rated the most important prescribed exercises. Approximately 50% of coaches used plyometrics such as depth jumps, box drills, and standing jumps. Ninety-four percent indicated they conducted physical testing on their rowers, typically assessing cardiovascular endurance (80%), muscular power (70%), muscular strength (70%), and anaerobic capacity (57%). This research represents the only published survey to date on the S&C practices in rowing within Great Britain. PMID:21311351

Gee, Thomas I; Olsen, Peter D; Berger, Nicolas J; Golby, Jim; Thompson, Kevin G

2011-03-01

221

Making High-Tensile-Strength Amalgam Components  

NASA Technical Reports Server (NTRS)

Structural components made of amalgams can be made to have tensile strengths much greater than previously known to be possible. Amalgams, perhaps best known for their use in dental fillings, have several useful attributes, including room-temperature fabrication, corrosion resistance, dimensional stability, and high compressive strength. However, the range of applications of amalgams has been limited by their very small tensile strengths. Now, it has been discovered that the tensile strength of an amalgam depends critically on the sizes and shapes of the particles from which it is made and, consequently, the tensile strength can be greatly increased through suitable choice of the particles. Heretofore, the powder particles used to make amalgams have been, variously, in the form of micron-sized spheroids or flakes. The tensile reinforcement contributed by the spheroids and flakes is minimal because fracture paths simply go around these particles. However, if spheroids or flakes are replaced by strands having greater lengths, then tensile reinforcement can be increased significantly. The feasibility of this concept was shown in an experiment in which electrical copper wires, serving as demonstration substitutes for copper powder particles, were triturated with gallium by use of a mortar and pestle and the resulting amalgam was compressed into a mold. The tensile strength of the amalgam specimen was then measured and found to be greater than 10(exp 4) psi (greater than about 69 MPa). Much remains to be done to optimize the properties of amalgams for various applications through suitable choice of starting constituents and modification of the trituration and molding processes. The choice of wire size and composition are expected to be especially important. Perusal of phase diagrams of metal mixtures could give insight that would enable choices of solid and liquid metal constituents. Finally, whereas heretofore, only binary alloys have been considered for amalgams, ternary additions to liquid or solid components should be considered as means to impart desired properties to amalgams.

Grugel, Richard

2008-01-01

222

Effect of status epilepticus and antiepileptic drugs on CYP2E1 brain expression.  

PubMed

P450 metabolic enzymes are expressed in the human and rodent brain. Recent data support their involvement in the pathophysiology of epilepsy. However, the determinants of metabolic enzyme expression in the epileptic brain are unclear. We tested the hypothesis that status epilepticus (SE) or exposure to phenytoin or phenobarbital affects brain expression of the metabolic enzyme CYP2E1. SE was induced in C57BL/6J mice by systemic kainic acid. Brain CYP2E1 expression was evaluated 18-24h after severe SE by immunohistochemistry. Co-localization with neuronal nuclei (NEUN), glial fibrillary acidic protein (GFAP) and CD31 was determined by confocal microscopy. The effect of phenytoin, carbamazepine and phenobarbital on CYP2E1 expression was evaluated in vivo or by using organotypic hippocampal cultures in vitro. CYP2E1 expression was investigated in brain resections from a cohort of drug-resistant epileptic brain resections and human endothelial cultures (EPI-EC). Immunohistochemistry showed an increase of CYP2E1 expression limited to hippocampal CA2/3 and hilar neurons after severe SE in mice. CYP2E1 expression was also observed at the astrocyte-vascular interface. Analysis of human brain specimens revealed CYP2E1 expression in neurons and vascular endothelial cells (EC). CYP2E1 was expressed in cultured human EC and over-expressed by EPI-EC. When analyzing the effect of drug exposure on CYP2E1 expression we found that, in vivo or in vitro, ethanol increased CYP2E1 levels in the brain and liver. Treatment with phenytoin induced localized CYP2E1 expression in the brain whereas no significant effects were exerted by carbamazepine or phenobarbital. Our data indicate that the effect of acute SE on brain CYP2E1 expression is localized and cell specific. Exposure to selected anti-epileptic drugs could play a role in determining CYP2E1 brain expression. Additional investigation is required to fully reproduce the culprits of P450 enzyme expression as observed in the human epileptic brain. PMID:25280786

Boussadia, B; Ghosh, C; Plaud, C; Pascussi, J M; de Bock, F; Rousset, M C; Janigro, D; Marchi, N

2014-10-01

223

Advances in paediatric strength assessment: changing our perspective on strength development  

Microsoft Academic Search

Our knowledge of the age and sex associated changes in strength during childhood and adolescence is relatively limited compared to other physiological parameters. However, those studies available on the age and sex associated change in strength are relatively consistent, especially for the lower limbs. Caution must be taken when transferring this knowledge to other muscle joints as the development in

Mark De Ste Croix

2007-01-01

224

Burst Strength of Tubing and Casing Based on Twin Shear Unified Strength Theory  

PubMed Central

The internal pressure strength of tubing and casing often cannot satisfy the design requirements in high pressure, high temperature and high H2S gas wells. Also, the practical safety coefficient of some wells is lower than the design standard according to the current API 5C3 standard, which brings some perplexity to the design. The ISO 10400: 2007 provides the model which can calculate the burst strength of tubing and casing better than API 5C3 standard, but the calculation accuracy is not desirable because about 50 percent predictive values are remarkably higher than real burst values. So, for the sake of improving strength design of tubing and casing, this paper deduces the plastic limit pressure of tubing and casing under internal pressure by applying the twin shear unified strength theory. According to the research of the influence rule of yield-to-tensile strength ratio and mechanical properties on the burst strength of tubing and casing, the more precise calculation model of tubing-casing's burst strength has been established with material hardening and intermediate principal stress. Numerical and experimental comparisons show that the new burst strength model is much closer to the real burst values than that of other models. The research results provide an important reference to optimize the tubing and casing design of deep and ultra-deep wells. PMID:25397886

Lin, Yuanhua; Deng, Kuanhai; Sun, Yongxing; Zeng, Dezhi; Liu, Wanying; Kong, Xiangwei; Singh, Ambrish

2014-01-01

225

Effect of conditioning temperature on the strength and permeability of normal- and high-strength concrete  

Microsoft Academic Search

In order to evaluate the effect of the conditioning temperature on strength and permeability properties of concrete a series of compressive, indirect tensile and permeability tests were performed on concretes (designed to have 28-day compressive strengths of 40 and 100 N\\/mm2) conditioned at temperatures of 85 and 105 °C. The results show that, for both the normal- (NSC) and the

D. R. Gardner; R. J. Lark; B. Barr

2005-01-01

226

Method for producing high dielectric strength microvalves  

DOEpatents

A microvalve having a cast-in-place and lithographically shaped mobile, polymer monolith for fluid flow control in microfluidic devices and method of manufacture. The microvalve contains a porous fluorinated polymer monolithic element whose pores are filled with an electrically insulating, high dielectric strength fluid, typically a perfluorinated liquid. This combination provides a microvalve that combines high dielectric strength with extremely low electrical conductivity. These microvalves have been shown to have resistivities of at least 100 G.OMEGA. and are compatible with solvents such as water at a pH between 2.7 and 9.0, 1-1 propanol, acetonitrile, and acetone.

Kirby, Brian J. (San Francisco, CA); Reichmuth, David S. (Oakland, CA); Shepodd, Timothy J. (Livermore, CA)

2006-04-04

227

Structure-strength relations in mammalian tendon.  

PubMed Central

The stress-strain relations in mammalian tendon are analyzed in terms of the structure and mechanics of its constituents. The model considers the tensile and bending strength of the collagen fibers, the tensile strength of the elastin fibers, and the interaction between the matrix and the collagen fibers. The stress-strain relations are solved through variational considerations by assuming that the fibermaxtrix interactions can be modeled as beam on elastic foundation. The tissue thus modeled is a hyperelastic material. It is further shown that on the basis of the model, the dominant parameters to the tendon's behavior can be evaluated from simple tensile tests. PMID:728528

Lanir, Y

1978-01-01

228

Size effect on flexural, splitting tensile, and torsional strengths of high-strength concrete  

SciTech Connect

This paper presents the results of an investigation into the size effect on flexural, splitting tensile, and torsional strengths of high-strength concrete (HSC) with normal aggregate (crushed limestone) and lightweight aggregate (sintered fly ash). The Bazant`s size effect law gives a very good fit to the flexural strengths of both normal and lightweight aggregate HSC measured from beams of different sizes. As observed in the size effect curve, the fracture behavior of the lightweight HSC seems more brittle than that of the normal HSC. Linear elastic fracture mechanics may still be less applicable to HSC in the normal size range than nonlinear fracture mechanics. A reverse size effect is observed in the prism splitting tensile strengths of both normal and light-weight HSC and possible mechanisms of the reverse size effect are discussed. The torsional strength of the lightweight HSC appears to have a stronger size dependency than that of the normal HSC.

Zhou, F.P.; Balendran, R.V.; Jeary, A.P. [City Univ. of Hong Kong (Hong Kong). Dept. of Building and Construction] [City Univ. of Hong Kong (Hong Kong). Dept. of Building and Construction

1998-12-01

229

Candida albicans Modulates Host Defense by Biosynthesizing the Pro-Resolving Mediator Resolvin E1  

PubMed Central

Candida albicans is an opportunistic fungal pathogen of humans that resides commensally on epithelial surfaces, but can cause inflammation when pathogenic. Resolvins are a class of anti-inflammatory lipids derived from omega-3 polyunsaturated fatty acids (PUFA) that attenuate neutrophil migration during the resolution phase of inflammation. In this report we demonstrate that C. albicans biosynthesizes resolvins that are chemically identical to those produced by human cells. In contrast to the trans-cellular biosynthesis of human Resolvin E1 (RvE1), RvE1 biosynthesis in C. albicans occurs in the absence of other cellular partners. C. albicans biosynthesis of RvE1 is sensitive to lipoxygenase and cytochrome P450 monoxygenase inhibitors. We show that 10nM RvE1 reduces neutrophil chemotaxis in response to IL-8; 1nM RvE1 enhanced phagocytosis of Candida by human neutrophils, as well as intracellular ROS generation and killing, while having no direct affect on neutrophil motility. In a mouse model of systemic candidiasis, RvE1 stimulated clearance of the fungus from circulating blood. These results reveal an inter-species chemical signaling system that modulates host immune functions and may play a role in balancing host carriage of commensal and pathogenic C. albicans. PMID:18091990

Haas-Stapleton, Eric J.; Lu, Yan; Hong, Song; Arita, Makoto; Favoreto, Silvio; Nigam, Santosh; Serhan, Charles N.; Agabian, Nina

2007-01-01

230

Adenovirus E1A specifically blocks SWI/SNF-dependent transcriptional activation.  

PubMed Central

Expression of the adenovirus E1A243 oncoprotein in Saccharomyces cerevisiae produces a slow-growth phenotype with accumulation of cells in the G1 phase of the cell cycle. This effect is due to the N-terminal and CR1 domains of E1A243, which in rodent cells are involved in triggering cellular transformation and also in binding to the cellular transcriptional coactivator p300. A genetic screen was undertaken to identify genes required for the function of E1A243 in S. cerevisiae. This screen identified SNF12, a gene encoding the 73-kDa subunit of the SWI/SNF transcriptional regulatory complex. Mutation of genes encoding known members of the SWI/SNF complex also led to loss of E1A function, suggesting that the SWI/SNF complex is a target of E1A243. Moreover, expression of E1A in wild-type cells specifically blocked transcriptional activation of the INO1 and SUC2 genes, whose activation pathways are distinct but have a common requirement for the SWI/SNF complex. These data demonstrate a specific functional interaction between E1A and the SWI/SNF complex and suggest that a similar interaction takes place in rodent and human cells. PMID:8816487

Miller, M E; Cairns, B R; Levinson, R S; Yamamoto, K R; Engel, D A; Smith, M M

1996-01-01

231

Suppression of mutations in two Saccharomyces cerevisiae genes by the adenovirus E1A protein.  

PubMed Central

The protein products of the adenoviral E1A gene are implicated in a variety of transcriptional and cell cycle events, involving interactions with several proteins present in human cells, including parts of the transcriptional machinery and negative regulators of cell division such as the Rb gene product and p107. To determine if there are functional homologs of E1A in Saccharomyces cerevisiae, we have developed a genetic screen for mutants that depend on E1A for growth. The screen is based on a colony color sectoring assay which allows the identification of mutants dependent on the maintenance and expression of an E1A-containing plasmid. Using this screen, we have isolated five mutants that depend on expression of the 12S or 13S cDNA of E1A for growth. A plasmid shuffle assay confirms that the plasmid-dependent phenotype is due to the presence of either the 12S or the 13S E1A cDNA and that both forms of E1A rescue growth of all mutants equally well. The five mutants fall into two classes that were named web1 and web2 (for "wants E1A badly"). Plasmid shuffle assays with mutant forms of E1A show that conserved region 1 (CR1) is required for rescue of the growth of the web1 and web2 E1A-dependent yeast mutants, while the N-terminal 22 amino acids are only partially required; conserved region 2 (CR2) and the C terminus are dispensable. The phenotypes of mutants in both the web1 and the web2 groups are due to a single gene defect, and the yeast genes that fully complement the mutant phenotypes of both groups were cloned. The WEB1 gene sequence encodes a 1,273-amino-acid protein that is identical to SEC31, a protein involved in the budding of transport vesicles from the endoplasmic reticulum. The WEB2 gene encodes a 1,522-amino-acid protein with homology to nucleic acid-dependent ATPases. Deletion of either WEB1 or WEB2 is lethal. Expression of E1A is not able to rescue the lethality of either the web1 or the web2 null allele, implying allele-specific mutations that lead to E1A dependence. PMID:7760818

Zieler, H A; Walberg, M; Berg, P

1995-01-01

232

Suppression of mutations in two Saccharomyces cerevisiae genes by the adenovirus E1A protein.  

PubMed

The protein products of the adenoviral E1A gene are implicated in a variety of transcriptional and cell cycle events, involving interactions with several proteins present in human cells, including parts of the transcriptional machinery and negative regulators of cell division such as the Rb gene product and p107. To determine if there are functional homologs of E1A in Saccharomyces cerevisiae, we have developed a genetic screen for mutants that depend on E1A for growth. The screen is based on a colony color sectoring assay which allows the identification of mutants dependent on the maintenance and expression of an E1A-containing plasmid. Using this screen, we have isolated five mutants that depend on expression of the 12S or 13S cDNA of E1A for growth. A plasmid shuffle assay confirms that the plasmid-dependent phenotype is due to the presence of either the 12S or the 13S E1A cDNA and that both forms of E1A rescue growth of all mutants equally well. The five mutants fall into two classes that were named web1 and web2 (for "wants E1A badly"). Plasmid shuffle assays with mutant forms of E1A show that conserved region 1 (CR1) is required for rescue of the growth of the web1 and web2 E1A-dependent yeast mutants, while the N-terminal 22 amino acids are only partially required; conserved region 2 (CR2) and the C terminus are dispensable. The phenotypes of mutants in both the web1 and the web2 groups are due to a single gene defect, and the yeast genes that fully complement the mutant phenotypes of both groups were cloned. The WEB1 gene sequence encodes a 1,273-amino-acid protein that is identical to SEC31, a protein involved in the budding of transport vesicles from the endoplasmic reticulum. The WEB2 gene encodes a 1,522-amino-acid protein with homology to nucleic acid-dependent ATPases. Deletion of either WEB1 or WEB2 is lethal. Expression of E1A is not able to rescue the lethality of either the web1 or the web2 null allele, implying allele-specific mutations that lead to E1A dependence. PMID:7760818

Zieler, H A; Walberg, M; Berg, P

1995-06-01

233

Iron and CYP2E1-dependent oxidative stress and toxicity.  

PubMed

Iron plays a critical role in catalyzing the formation of potent oxidants. Increases in iron content enhance oxidative stress, whereas removal of iron deceases such stress. An association between iron and alcoholic liver injury has been proposed. The ability of iron to modulate the biochemical and toxicologic actions of cytochrome P450 2E1 (CYP2E1) has been evaluated by using isolated microsomes and intact liver cells. The ability of different iron complexes to stimulate microsomal lipid peroxidation and hydroxyl radical production during reduced form of nicotinamide adenine dinucleotide phosphate (NADPH)- and reduced form of nicotinamide adenine dinucleotide (NADH)-dependent electron transfer has been characterized. Certain iron complexes have been shown to be effective in promoting lipid peroxidation; others are better catalysts of hydroxyl radical production as a complex pattern has been found. Reactive oxygen production, lipid peroxidation, and interaction with iron chelates have been shown to be enhanced with microsomes isolated from ethanol-treated rats with elevated levels of CYP2E1. This increase was prevented by anti-CYP2E1 immunoglobulin (Ig)G or chemical inhibitors of CYP2E1. Thus, in the presence of iron complexes, microsomes enriched in CYP2E1 are especially reactive in generation of reactive oxygen species. To assess the toxicologic significance of this iron-CYP2E1 interaction, iron (ferric-nitrilotriacetate) was added to HepG2 cells, which were engineered to express the human CYP2E1. Ferric-nitrilotriacetate produced a greater toxicity in the CYP2E1-expressing HepG2 cells than that in control HepG2 cells. This enhanced, synergistic toxicity was blocked by antioxidants and inhibitors of CYP2E1. Mitochondrial membrane potential and ATP levels were decreased, and damage to the mitochondria played a critical role in the CYP2E1-plus-iron-dependent toxicity. These results support the suggestion that low concentrations of iron and polyunsaturated fatty acids can act as priming or sensitizing factors for CYP2E1-induced injury in HepG2 cells and hepatocytes. Such interactions may play a role in alcohol-induced liver injury. PMID:12957295

Cederbaum, Arthur I

2003-06-01

234

Mutation of E1? gene in a female patient with pyruvate dehydrogenase deficiency due to rapid degradation of E1 protein  

Microsoft Academic Search

Summary A mutation of an insertion of 4 bp in the gene for the a subunit of pyruvate dehydrogenase (E1a) was found in a female with pyruvate dehydrogenase deficiency due to the rapid degradation of a and ß subunit proteins of pyruvate dehydrogenase. This mutation caused a frameshift that altered the amino acid sequence and created a premature stop codon.

M. Ito; A. H. M. M. Huq; E. Naito; T. Saijo; E. Takeda; Y. Kuroda

1992-01-01

235

Practical Estimates of Tensile Strength and Hoek-Brown Strength Parameter m i of Brittle Rocks  

NASA Astrophysics Data System (ADS)

By applying the Griffith stress criterion of brittle failure, one can find that the uniaxial compressive strength (?c) of rocks is eight times the value of the uniaxial tensile strength (?t). The Griffith strength ratio is smaller than what is normally measured for rocks, even with the consideration of crack closure. The reason is that Griffith’s theories address only the initiation of failure. Under tensile conditions, the crack propagation is unstable so that the tensile crack propagation stress (?cd)t and the peak tensile strength ?t are almost identical to the tensile crack initiation stress (?ci)t. On the other hand, the crack growth after crack initiation is stable under a predominantly compressive condition. Additional loading is required in compression to bring the stress from the crack initiation stress ?ci to the peak strength ?c. It is proposed to estimate the tensile strength of strong brittle rocks from the strength ratio of R = {{?_{text{c}} }/{left| {?_{text{t} } right|}}} = 8{{?_{text{c}} }/{?_{text{ci} }}}. The term {{?_{text{c}} }/{?_{text{ci} }}} accounts for the difference of crack growth or propagation in tension and compression in uniaxial compression tests. {{?c }/{?_{ci }}} depends on rock heterogeneity and is larger for coarse grained rocks than for fine grained rocks. ?ci can be obtained from volumetric strain measurement or acoustic emission (AE) monitoring. With the strength ratio R determined, the tensile strength can be indirectly obtained from left| {?_{text{t}} } right| = {{?_{text{c}} }/R} = {{?_{text{ci}} }/8}. It is found that the predicted tensile strengths using this method are in good agreement with test data. Finally, a practical estimate of the Hoek-Brown strength parameter m i is presented and a bi-segmental or multi-segmental representation of the Hoek-Brown strength envelope is suggested for some brittle rocks. In this fashion, the rock strength parameters like ?t and m i, which require specialty tests such as direct tensile (or Brazilian) and triaxial compression tests for their determination, can be reasonably estimated from uniaxial compression tests.

Cai, M.

2010-03-01

236

Oscillator strengths and transition probabilities from the Breit-Pauli R-matrix method: Ne IV  

NASA Astrophysics Data System (ADS)

The atomic parameters-oscillator strengths, line strengths, radiative decay rates (A), and lifetimes-for fine structure transitions of electric dipole (E1) type for the astrophysically abundant ion Ne IV are presented. The results include 868 fine structure levels with n? 10, l? 9, and 1/2?J? 19/2 of even and odd parities, and the corresponding 83,767 E1 transitions. The calculations were carried out using the relativistic Breit-Pauli R-matrix method in the close coupling approximation. The transitions have been identified spectroscopically using an algorithm based on quantum defect analysis and other criteria. The calculated energies agree with the 103 observed and identified energies to within 3% or better for most of the levels. Some larger differences are also noted. The A-values show good to fair agreement with the very limited number of available transitions in the table compiled by NIST, but show very good agreement with the latest published multi-configuration Hartree-Fock calculations. The present transitions should be useful for diagnostics as well as for precise and complete spectral modeling in the soft X-ray to infra-red regions of astrophysical and laboratory plasmas.

Nahar, Sultana N.

2014-09-01

237

Dielectric strength of sulfur hexafluoride upon condensation  

SciTech Connect

The behavior of sulfur hexafluoride in a sealed high-voltage device has been modeled for cooling to the condensation point of the insulating medium. The temperature dependences of the breakdown voltages of sulfur hexafluoride have been investigated for several interelectrode separations. The dielectric strength has been shown to decrease upon condensation with formation of a bridge of boiling liquid phase between the electrodes.

Antonov, A.V.; Lyapin, A.G.; Popkov, V.I.

1983-01-01

238

Structure and Strength in Causal Induction  

ERIC Educational Resources Information Center

We present a framework for the rational analysis of elemental causal induction--learning about the existence of a relationship between a single cause and effect--based upon causal graphical models. This framework makes precise the distinction between causal structure and causal strength: the difference between asking whether a causal relationship…

Griffiths, Thomas L.; Tenenbaum, Joshua B.

2005-01-01

239

Innovative Degree Programs Matched to City Strengths  

ERIC Educational Resources Information Center

In recent years, IUPUI has steadily acquired a considerable national reputation as an up-and-coming university. Some of the reasons for this recognition include the RISE Initiative and the large number of innovative degree programs recently started at IUPUI based on campus strengths and the priorities of the city of Indianapolis. Some specific…

Sukhatme, Uday

2011-01-01

240

Got LEGO Bricks? Children with Spatial Strengths  

ERIC Educational Resources Information Center

Individuals with spatial strengths have preferences for visual ideation, holistic reasoning, and innovation. With the emphasis on verbal skills, American schools rarely provide opportunities for children to excel in these areas. Standardized assessments used to judge achievement do not value reflective thinking and innovation; therefore, students…

Mann, Rebecca

2013-01-01

241

Compacted Soil Liner Interface Strength Importance  

E-print Network

Case Study Compacted Soil Liner Interface Strength Importance Timothy D. Stark, F.ASCE1 ; Hangseok interface is not the geomembrane (GM)/compacted low-permeability soil liner (LPSL) but a soil­soil interface placing the cover soil from bottom to top. DOI: 10.1061/(ASCE)GT.1943-5606 .0000556. © 2012 American

242

Strength Training. A Key to Athletic Training.  

ERIC Educational Resources Information Center

Characteristics of an effective strength training program are analyzed and descriptions are offered of different kinds of weight training activities. Comparisons are made between concentric, isometric, eccentric, and isokinetic training methods. The fundamentals and techniques of an exemplary training program are outlined and the organization and…

Whiteside, Patricia W.

243

Considerations on strength of intact sedimentary rocks  

Microsoft Academic Search

This study presents the results of laboratory testing of sedimentary rocks under point loading as well as in uniaxial and triaxial compression. From the statistical analysis of the data, different conversion factors relating uniaxial compressive and point loading strength were determined for soft to strong rocks. Additionally, the material constant mi, an input parameter for the Hoek and Brown failure

G Tsiambaos; N Sabatakakis

2004-01-01

244

Physical Property Measurements: Unconfined Compressive Strength (UCS)  

NSDL National Science Digital Library

This site, by the Colorado School of Mines, addresses the properties of a measurement technique called unconfined compression strength (UCS). Along with defining the technique, the website shows different experiments, pictures and diagrams associated with UCS. This well organized work will be a valuable asset for any geology or engineering classroom.

Ozdemir, Levent

2008-09-17

245

THE PROOFTHEORETIC STRENGTH OF THE DUSHNIKMILLER THEOREM  

E-print Network

THE PROOF­THEORETIC STRENGTH OF THE DUSHNIK­MILLER THEOREM FOR COUNTABLE LINEAR ORDERS Rodney G that the Dushnik­Miller Theorem for countable linear order­ ings (stating that any countable linear ordering has theorem of ``ordinary'' mathematics by trying to prove the axiom from the theorem (over a weaker ``base

246

ROOM TEMPERATURE STRENGTH DEGRADATION OF OPTICAL FIBERS  

E-print Network

ROOM TEMPERATURE STRENGTH DEGRADATION OF OPTICAL FIBERS C. R. Kurkjian, H. H. Yuce Bell of elevated temperatures and at room temperature. Using these data we show that accelerated testing can be used to predict ambient temperature behavior. An activation energy of '90 kJ.mo11 describes the shift

Matthewson, M. John

247

Predicting maximal grip strength using hand circumference  

Microsoft Academic Search

The objective of this study was to analyze the correlations between anthropometric data and maximal grip strength (MGS) in order to establish a simple model to predict “normal” MGS. Randomized bilateral measurement of MGS was performed on a homogeneous population of 100 subjects. MGS was measured according to a standardized protocol with three dynamometers (Jamar, Myogrip and Martin Vigorimeter) for

Ke Li; David J. Hewson; Jacques Duchêne; Jean-Yves Hogrel

2010-01-01

248

Nuclear threshold effects and neutron strength functions  

NASA Astrophysics Data System (ADS)

The present work is devoted to study of spectroscopic aspects, in terms of neutron strength function, for the threshold effects with non-light nuclei. Relations to the neutron strength functions of the anomal effects observed at threshold of neutron analogue channel, in deuteron stripping reactions on A ? 90 mass target nuclei and in nucleon mirror reactions with A ? 30 nuclei, are established. It is proved that these threshold effects follow the mass dependance of the neutron strength functions. The connection between threshold effects and neutron strength functions, proves that the threshold effects are related to spectroscopy of ancestral zero-energy neutron particle resonance. One can conclude the threshold effects depend not only on penetration factors of opening neutron channel, as in Cusp Theory, but also on Multichannel Reaction Dynamics as well as on Spectroscopy of neutron threshold state. The present study is based on Reduced Scattering Matrix, describing the effect of invisible threshold channel on open observed ones. The determining role of Nuclear Reaction Dynamics, Quasiresonant Scattering and Spectroscopy of Neutron Threshold State, on threshold effects is evinced.

Comisel, H.; Hategan, C.; Wolter, H. H.

2010-07-01

249

Determinants of eggshell strength in endangered raptors  

Microsoft Academic Search

We compared eggshell strength in a group of falcon taxa including the peregrine falcon (Falco peregrinus peregrinus), the red shaheen falcon (F. peregrinus babylonicus), the saker falcon (F. cherrug), the gyr falcon (F. rusticolus) and some interspecific and intraspecific hybrids. Our results showed that smaller falcons (o1,000 g) of the peregrine group have eggshells that are significantly softer ( x

Aurora M. Castilla; Anthony Herrel; Stefan Van Dongen; Naoki Furio; Juan José Negro

2009-01-01

250

Giant monopole resonance strength in Si-28  

E-print Network

The giant resonance region in Si-28 was studied with inelastic scattering of 240 MeV alpha particles at small angles including 0 degrees. The giant resonance peak extended from E-x=12 MeV to 35 MeV and E0 strength corresponding to 54 +/- 6...

Youngblood, David H.; Clark, HL; Lui, YW.

1998-01-01

251

Predicting tie strength with social media  

Microsoft Academic Search

Social media treats all users the same: trusted friend or total stranger, with little or nothing in between. In reality, rela- tionships fall everywhere along this spectrum, a topic social science has investigated for decades under the theme of tie strength. Our work bridges this gap between theory and practice. In this paper, we present a predictive model that maps

Eric Gilbert; Karrie Karahalios

2009-01-01

252

Psychrophilic anaerobic treatment of low strength wastewaters  

Microsoft Academic Search

Psychrophilic (2 to 20°C) anaerobic treatment of low strength synthetic and malting wastewater was investigated using a single and hvo module expanded granular sludge bed (EGSB) reactor system. The chemical oxygen demand (COD) removal efftciencies found in the experiments exceeded 90% in the single module reactor at an organic loading rate up to 12g COD dm?3’ day?1 and a HRT

Salih Rebac; Jules B. van Lier; Piet Lens; Alfons J. M. Stams; Freddy Dekkers; Koen Th. M. Swinkels; Gatze Lettinga

1999-01-01

253

Strength and durability of lightweight concrete  

Microsoft Academic Search

Two lightweight aggregate concretes, SLWC35 and SLWC50, of 35 and 50 MPa 28 day cube compressive strength were cast. The concrete specimens made with lightweight coarse aggregates and a dune sand were continuously cured in water for one or 7 days and then exposed to predominantly hot and humid seaside ambient conditions containing air-borne salts. After 7 days of initial

M. N Haque; H Al-Khaiat; O Kayali

2004-01-01

254

Oscillator strength of instantaneous diatomic sodium molecules  

NASA Astrophysics Data System (ADS)

We introduce definitely the notion of instantaneous molecules, real or fictitious, in spite of its utilization in certain fields of the supraconductivity, genetics and advanced medical research. Calculation of the oscillator strength of instantaneous sodium diatomic molecules gives [ f mol]Na 2( i)=6,86. This method is transposable at lithium and other Ia elements.

Perny, G.

1991-12-01

255

The Brittle Strength of Orthotropic Materials  

Microsoft Academic Search

A phenomenological fracture condition is proposed for ortho tropic brittle materials. It contains nine material parameters and can account for widely differing compressive and tensile strengths in various directions. The proposed fracture condition is devel oped, purely on formal grounds, by borrowing features of the Mises-Schleicher isotropic yield condition and Hill's orthotropic yield condition. Comparison with experimental data on a

Oscar Hoffman

1967-01-01

256

Silicon nitride having a high tensile strength  

DOEpatents

A silicon nitride ceramic comprising: a) inclusions no greater than 25 microns in length, b) agglomerates no greater than 20 microns in diameter, and c) a surface finish of less than about 8 microinches, said ceramic having a four-point flexural strength of at least about 900 MPa.

Pujari, Vimal K. (Northboro, MA); Tracey, Dennis M. (Medfield, MA); Foley, Michael R. (Oxford, MA); Paille, Norman I. (Oxford, MA); Pelletier, Paul J. (Millbury, MA); Sales, Lenny C. (Grafton, MA); Willkens, Craig A. (Sterling, MA); Yeckley, Russell L. (Oakham, MA)

1996-01-01

257

Al Roy: The First Modern Strength Coach  

ERIC Educational Resources Information Center

This article presents a historical perspective through the story of Alvin Roy, the first modern strength coach. Roy went against the common belief in the 1950s that weight lifting made athletes slow and bulky. When the football coaches at Istrouma High School in Baton Rouge, Louisiana, allowed him to set up and supervise a weight-training program,…

Todd, Terry

2008-01-01

258

Pranayama increases grip strength without lateralized effects.  

PubMed

The present study was conducted to determine whether breathing through a particular nostril has a lateralized effect on hand grip strength. 130 right hand dominant, school children between 11 and 18 yrs of age were randomly assigned to 5 groups. Each group had a specific yoga practice in addition to the regular program for a 10 day yoga camp. The practices were: (1) right-, (2) left-, (3) alternate- nostril breathing (4), breath awareness and (5) practice of mudras. Hand grip strength of both hands was assessed initially and at the end of 10 days for all 5 groups. The right-, left- and alternate-nostril breathing groups had a significant increase in grip strength of both hands, ranging from 4.1% to 6.5%, at the end of the camp though without any lateralization effect. The breath awareness and mudra groups showed no change. Hence the present results suggest that yoga breathing through a particular nostril, or through alternate nostrils increases hand grip strength of both hands without lateralization. PMID:9142556

Raghuraj, P; Nagarathna, R; Nagendra, H R; Telles, S

1997-04-01

259

Educating industrial-strength software engineers  

Microsoft Academic Search

A roadmap is proposed for integrating trends in software technology and product development into a graduate curriculum in software engineering. We contend that the causal relationship between building model solutions and developing products from these solutions, provides a sound basis for industrial strength software engineering. We illustrate the impact of modern software technology on the two fundamental, complementary sets of

Jorge L. Díaz-Herrera; Gerald M. Powell

1998-01-01

260

Prediction of the interplanetary magnetic field strength  

Microsoft Academic Search

A new model of the coronal and interplanetary magnetic field can predict both the interplanetary magnetic field strength and its polarity from measurements of the photospheric magnetic field. The model includes the effects of the large-scale horizontal electric currents flowing in the inner corona, of the warped heliospheric current sheet in the upper corona, and of volume currents flowing in

Xuepu Zhao; J. Todd Hoeksema

1995-01-01

261

568. Comparison of Antigen-Specific Immune Responses Elicited by Recombinant Simian Adenoviral Vectors with Deletions in Either E1, or E1\\/E3, or E1\\/E4 Regions  

Microsoft Academic Search

Replication-defective adenoviral vectors based on human serotype 5 (H5) have emerged as very effective vaccine carriers. However, the neutralizing antibodies to AdH5 vector by previous natural infections will very likely impair its vaccine efficacy. Therefore, our lab developed replication-defective simian adenoviral C7 vectors to circumvent interference by pre-existing immunity to human AdH5. Early regions of AdH5 genome, including E1, E3,

Yan Zhi; Gary P. Kobinger; Heather Jordan; Guangping Gao; James M. Wilson

2004-01-01

262

Tie Strength in Question & Answer on Social Network Sites  

E-print Network

Tie Strength in Question & Answer on Social Network Sites Katrina Panovich, Robert C. Miller, David with opportunities to better observe this process. In this paper, we relate question answering to tie strength of tie strength in question answers. We used previous research on tie strength in social media

263

Study on strength, elastic modulus of artifical lightweight aggregate concrete  

NASA Astrophysics Data System (ADS)

Aggregate strength of artificial lightweight concrete and concrete used with this artificial lightweight aggregate can be expected to have nearly the same strength as normal weight concrete. An experimental study of properties of concrete strength and correlation between compressive and tensile and flexural strengths and elastic modulus of its concrete was made.

Kakizaki, M.

1982-04-01

264

Assessing the Strengths of Mental Health Consumers: A Systematic Review  

ERIC Educational Resources Information Center

Strengths assessments focus on the individual's talents, abilities, resources, and strengths. No systematic review of strengths assessments for use within mental health populations has been published. The aims of this study were to describe and evaluate strengths assessments for use within mental health services. A systematic review identified 12…

Bird, Victoria J.; Le Boutillier, Clair; Leamy, Mary; Larsen, John; Oades, Lindsay G.; Williams, Julie; Slade, Mike

2012-01-01

265

Aluminum Rayleigh Taylor Strength Measurements and Calculations  

SciTech Connect

A traditional approach to the study of material strength has been revitalized at the Russian Federal Nuclear Center (VNIIEF). Rayleigh Taylor strength experiments have long been utilized to measure the material response of metals at high pressure and strain rates. A modulated (sinusoidal or sawtooth perturbation) surface is shocklessly (quasi-isentropically) accelerated by a high explosive (HE) driver, and radiography is used to measure the perturbation amplitude as a function of time. The Aluminum T-6061 targets are designed with several sets of two-dimensional sawtooth perturbations machined on the loading surface. The HE driver was designed to reach peak pressures in the range of 200 to 300 kbar and strain rates in the range of 10{sup 4} - 10{sup 6} s{sup -1}. The standard constitutive strength models, Steinberg-Guinan (SG) [1], Steinberg-Lund (SL) [2], Preston-Tonks-Wallace (PTW) [3], Johnson-Cooke (JC) [4], and Mechanical Threshold Stress (MTS) [5], have been calibrated by traditional techniques: (Hopkinson-Bar, Taylor impact, flyer plate/shock-driven experiments). The VNIIEF experimental series accesses a strain rate regime not attainable using traditional methods. We have performed a detailed numerical study with a two-dimensional Arbitrary Lagrangian Eulerian hydrodynamics computer code containing several constitutive strength models to predict the perturbation growth. Results show that the capabilities of the computational methodology predict the amplitude growth to within 5 percent of the measured data, thus validating both the code and the strength models under the given conditions and setting the stage for credible future design work using different materials.

Lindquist, M J; Cavallo, R M; Lorenz, K T; Pollaine, S M; Remington, B A; Raevsky, V A

2007-01-10

266

26 CFR 301.6511(e)-1 - Special rules applicable to manufactured sugar.  

Code of Federal Regulations, 2014 CFR

...Special rules applicable to manufactured sugar. 301.6511(e)-1 Section 301...Special rules applicable to manufactured sugar. (a) Use as livestock feed and for...accrues as of the date the manufactured sugar, or article manufactured...

2014-04-01

267

26 CFR 301.6511(e)-1 - Special rules applicable to manufactured sugar.  

Code of Federal Regulations, 2013 CFR

...Special rules applicable to manufactured sugar. 301.6511(e)-1 Section 301...Special rules applicable to manufactured sugar. (a) Use as livestock feed and for...accrues as of the date the manufactured sugar, or article manufactured...

2013-04-01

268

26 CFR 301.6511(e)-1 - Special rules applicable to manufactured sugar.  

Code of Federal Regulations, 2012 CFR

...Special rules applicable to manufactured sugar. 301.6511(e)-1 Section 301...Special rules applicable to manufactured sugar. (a) Use as livestock feed and for...accrues as of the date the manufactured sugar, or article manufactured...

2012-04-01

269

26 CFR 1.263(e)-1 - Expenditures in connection with certain railroad rolling stock.  

Code of Federal Regulations, 2011 CFR

...Expenditures in connection with certain railroad rolling stock. 1.263(e)-1...Expenditures in connection with certain railroad rolling stock. (a) Allowance of...with the rehabilitation of a unit of railroad rolling stock (as defined in...

2011-04-01

270

26 CFR 1.263(e)-1 - Expenditures in connection with certain railroad rolling stock.  

Code of Federal Regulations, 2012 CFR

...Expenditures in connection with certain railroad rolling stock. 1.263(e)-1...Expenditures in connection with certain railroad rolling stock. (a) Allowance of...with the rehabilitation of a unit of railroad rolling stock (as defined in...

2012-04-01

271

26 CFR 1.263(e)-1 - Expenditures in connection with certain railroad rolling stock.  

Code of Federal Regulations, 2014 CFR

...Expenditures in connection with certain railroad rolling stock. 1.263(e)-1...Expenditures in connection with certain railroad rolling stock. (a) Allowance of...with the rehabilitation of a unit of railroad rolling stock (as defined in...

2014-04-01

272

26 CFR 1.263(e)-1 - Expenditures in connection with certain railroad rolling stock.  

Code of Federal Regulations, 2013 CFR

...Expenditures in connection with certain railroad rolling stock. 1.263(e)-1...Expenditures in connection with certain railroad rolling stock. (a) Allowance of...with the rehabilitation of a unit of railroad rolling stock (as defined in...

2013-04-01

273

26 CFR 1.263(e)-1 - Expenditures in connection with certain railroad rolling stock.  

Code of Federal Regulations, 2010 CFR

...Expenditures in connection with certain railroad rolling stock. 1.263(e)-1...Expenditures in connection with certain railroad rolling stock. (a) Allowance of...with the rehabilitation of a unit of railroad rolling stock (as defined in...

2010-04-01

274

26 CFR 1.1031(e)-1 - Exchange of livestock of different sexes.  

Code of Federal Regulations, 2013 CFR

...false Exchange of livestock of different sexes. 1.1031(e)-1 Section 1.1031...1 Exchange of livestock of different sexes. Section 1031(e) provides that livestock of different sexes are not property of like kind....

2013-04-01

275

26 CFR 1.1031(e)-1 - Exchange of livestock of different sexes.  

Code of Federal Regulations, 2012 CFR

...false Exchange of livestock of different sexes. 1.1031(e)-1 Section 1.1031...1 Exchange of livestock of different sexes. Section 1031(e) provides that livestock of different sexes are not property of like kind....

2012-04-01

276

26 CFR 1.1031(e)-1 - Exchange of livestock of different sexes.  

Code of Federal Regulations, 2011 CFR

...false Exchange of livestock of different sexes. 1.1031(e)-1 Section 1.1031...1 Exchange of livestock of different sexes. Section 1031(e) provides that livestock of different sexes are not property of like kind....

2011-04-01

277

26 CFR 1.1031(e)-1 - Exchange of livestock of different sexes.  

Code of Federal Regulations, 2014 CFR

...false Exchange of livestock of different sexes. 1.1031(e)-1 Section 1.1031...1 Exchange of livestock of different sexes. Section 1031(e) provides that livestock of different sexes are not property of like kind....

2014-04-01

278

26 CFR 1.1397E-1 - Qualified zone academy bonds.  

Code of Federal Regulations, 2010 CFR

...Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Empowerment Zone Employment Credit § 1.1397E-1 Qualified zone academy bonds. (a) Overview. In general,...

2010-04-01

279

26 CFR 1.1031(e)-1 - Exchange of livestock of different sexes.  

Code of Federal Regulations, 2010 CFR

...true Exchange of livestock of different sexes. 1.1031(e)-1 Section 1.1031...1 Exchange of livestock of different sexes. Section 1031(e) provides that livestock of different sexes are not property of like kind....

2010-04-01

280

Predissociation in the E 1 , v1 state of the six natural isotopomers  

E-print Network

shielding and penetration effects3 and the E 1 , v 1 state was shown to play a prominent role. Against- trophysics perspective this state plays an important role in the photodissociation induced isotopic

Cacciani, Patrice

281

Natural history of the E1-like superfamily: implication for adenylation, sulfur transfer and ubiquitin conjugation  

PubMed Central

The E1-like superfamily is central to ubiquitin (Ub) conjugation, biosynthesis of cysteine, thiamine and MoCo and several secondary metabolites. Yet, its functional diversity and evolutionary history is not well-understood. We develop a natural classification of this superfamily and use it to decipher the major adaptive trends occurring in the evolution of the E1-like superfamily. Within the Rossmann fold, E1-like proteins are closest to NAD(P)/FAD-dependent dehydrogenases and S-AdoMet-dependent methyltransferases. Hence, their phosphotransfer activity is an independent catalytic “invention” with respect to such activities seen in other Rossmannoid folds. Sequence and structure analysis reveals a striking diversity of residues and structures involved in adenylation, sulfotransfer and substrate-binding between different E1-like families, allowing us to predict previously uncharacterized functional adaptations. E1-like proteins are fused to several previously undetected domains, such as a predicted sulfur transfer domain containing a novel superfamily of the TATA-binding protein fold, different types of catalytic domains, a novel winged helix-turn-helix domain and potential adaptor domains related to Ub conjugation. Based on these fusions we develop a generalized model for the linking of E1 catalyzed adenylation/thiolation with further down-stream reactions. This is likely to involve a dynamic interplay between the E1 active sites and diverse fused C-terminal domains. We also predict participation of E1-like domains in previously uncharacterized bacterial secondary metabolism pathways, new cysteine biosynthesis systems, such as those associated with archaeal O-phosphoseryl tRNA, metal-sulfur cluster assembly (e.g. in nitrogen fixation) and Ub-conjugation. Evolutionary reconstructions suggest that the last universal common ancestor (LUCA) contained a single E1-like domain possessing both phosphotransfer and thiolating activities and participating in multiple sulfotransfer reactions. The E1-like superfamily subsequently expanded to include 26 families clustering into three major radiations. These are broadly involved in ubiquitin activation, cofactor and cysteine biosynthesis, and biosynthesis of secondary metabolites. In light of this we present evidence that in eukaryotes other E1-like enzymes, such as Urm1, were independently recruited for Ubl conjugation, probably functioning without conventional E2-like enzymes. PMID:19089947

Burroughs, A. Maxwell; Iyer, Lakshminarayan M.; Aravind, L.

2009-01-01

282

Influence of Lactobacillus E1 on the storage stability in emulsion immobilization  

Microsoft Academic Search

A coacervation method with double emulsion strategy (w\\/o\\/w) was used to prepare immobilized Lactobacillus E1. Diatomite was chosen as the carrier for bacteria. Sodium alginate, dextrin and gelatin were used as protective solutes\\u000a for the preservation of Lactobacillus E1 and their effects on the storage viability during storage were discussed. The influence of storage temperature on the\\u000a storage viability was

Xin Sun; Xiguang Chen; Chengsheng Liu; Dongsu Cha; Hongni Peng

2009-01-01

283

Structure-function analysis of hepatitis C virus envelope glycoproteins E1 and E2.  

PubMed

Hepatitis C virus (HCV) is the leading cause of chronic liver disease in humans. The envelope proteins of HCV are potential candidates for vaccine development. The absence of three-dimensional (3D) structures for the functional domain of HCV envelope proteins [E1.E2] monomer complex has hindered overall understanding of the virus infection, and also structure-based drug design initiatives. In this study, we report a 3D model containing both E1 and E2 proteins of HCV using the recently published structure of the core domain of HCV E2 and the functional part of E1, and investigate immunogenic implications of the model. HCV [E1.E2] molecule is modeled by using aa205-319 of E1 to aa421-716 of E2. Published experimental data were used to further refine the [E1.E2] model. Based on the model, we predict 77 exposed residues and several antigenic sites within the [E1.E2] that could serve as vaccine epitopes. This study identifies eight peptides which have antigenic propensity and have two or more sequentially exposed amino acids and 12 singular sites are under negative selection pressure that can serve as vaccine or therapeutic targets. Our special interest is 285FLVGQLFTFSPRRHW299 which has five negatively selected sites (L286, V287, G288, T292, and G303) with three of them sequential and four amino acids exposed (F285, L286, T292, and R296). This peptide in the E1 protein maps to dengue envelope vaccine target identified previously by our group. Our model provides for the first time an overall view of both the HCV envelope proteins thereby allowing researchers explore structure-based drug design approaches. PMID:25245635

Nayak, Aparajita; Pattabiraman, Nagarajan; Fadra, Numrah; Goldman, Radoslav; Kosakovsky Pond, Sergei L; Mazumder, Raja

2014-10-15

284

Impact of resolvin e1 on murine neutrophil phagocytosis in type 2 diabetes.  

PubMed

Diabetic complications involve inflammation-mediated microvascular and macrovascular damage, disruption of lipid metabolism, glycosylation of proteins, and abnormalities of neutrophil-mediated events. Resolution of inflamed tissues to health and homeostasis is an active process mediated by endogenous lipid agonists, including lipoxins and resolvins. This proresolution system appears to be compromised in type 2 diabetes (T2D). The goal of this study was to investigate unresolved inflammation in T2D. Wild-type (WT) and genetically engineered mice, including T2D mice (db/db), transgenic mice overexpressing the human resolvin E1 (RvE1) receptor (ERV1), and a newly bred strain of db/ERV1 mice, were used to determine the impact of RvE1 on the phagocytosis of Porphyromonas gingivalis in T2D. Neutrophils were isolated and incubated with fluorescein isothiocyanate-labeled P. gingivalis, and phagocytosis was measured in a fluorochrome-based assay by flow cytometry. Mitogen-activated protein kinase (MAPK) (p42 and p44) and Akt (Thr308 and Ser473) phosphorylation was analyzed by Western blotting. The mouse dorsal air pouch model was used to evaluate the in vivo impact of RvE1. Results revealed that RvE1 increased the neutrophil phagocytosis of P. gingivalis in WT animals but had no impact in db/db animals. In ERV1-transgenic and ERV1-transgenic diabetic mice, phagocytosis was significantly increased. RvE1 decreased Akt and MAPK phosphorylation in the transgenic animals. In vivo dorsal air pouch studies revealed that RvE1 decreases neutrophil influx into the pouch and increases neutrophil phagocytosis of P. gingivalis in the transgenic animals; cutaneous fat deposition was reduced, as was macrophage infiltration. The results suggest that RvE1 rescues impaired neutrophil phagocytosis in obese T2D mice overexpressing ERV1. PMID:25486994

Herrera, Bruno S; Hasturk, Hatice; Kantarci, Alpdogan; Freire, Marcelo O; Nguyen, Olivia; Kansal, Shevali; Van Dyke, Thomas E

2015-02-01

285

The E1-E2 center in gallium arsenide is the divacancy.  

PubMed

Based on defect energy levels computed from first-principles calculations, it is shown the E1-E2 center in irradiated GaAs cannot be due to an isolated arsenic vacancy. The only simple intrinsic defect with levels compatible with E1 and E2 is the divacancy. The arsenic monovacancy is reassigned to the E3 center in irradiated GaAs. These new assignments are shown to reconcile a number of seemingly contradictory experimental observations. PMID:25634829

Schultz, Peter A

2015-02-25

286

Chlormethiazole inhibition of cytochrome P450 2E1 as assessed by chlorzoxazone hydroxylation in humans  

Microsoft Academic Search

Chlormethiazole is a sedative and anticonvulsive drug used in the treatment of alcohol withdrawal. Because it had been reported that chlormethiazole inhibits the alcohol-inducible cytochrome P450 2E1 in rat liver, we investigated the in vivo and in vitro effect of this drug on cytochrome P450 2E1 in human beings. The activity of this cytochrome was assessed using chlorzoxazone as a

AC Gebhardt; D Lucas; J Menez; HK Seitz

1997-01-01

287

The adenovirus E1A oncoprotein recruits the cellular TRRAP\\/GCN5 histone acetyltransferase complex  

Microsoft Academic Search

The adenovirus E1A oncoprotein stimulates cell growth and inhibits differentiation by deregulating the normal transcription program via interaction with positive and negative cellular effectors. E1A associates with transcriptional regulatory complexes containing p400 and TRRAP involved in chromatin remodeling and decondensation. TRRAP is a component of three distinct human histone acetyltransferase (HAT) complexes: the TIP60 complex and complexes containing GCN5 or

Steven E Lang; Patrick Hearing

2003-01-01

288

Transcriptional control by adenovirus E1A conserved region 3 via p300\\/CBP  

Microsoft Academic Search

The human adenovirus type 5 (HAdV-5) E1A 13S oncoprotein is a potent regulator of gene expression and is used extensively as a model for transcriptional activation. It possesses two inde- pendent transcriptional activation domains located in the N-terminus\\/conserved region (CR) 1 and CR3. The protein acetyltransferase p300 was previously identified by its association with the N-terminus\\/ CR1 portion of E1A

Peter Pelka; Jailal N. G. Ablack; Joseph Torchia; Andrew S. Turnell; Roger J. A. Grand; Joe S. Mymryk

2009-01-01

289

CYP2E1-dependent elevation of serum cholesterol, triglycerides, and hepatic bile acids by isoniazid  

SciTech Connect

Isoniazid is the first-line medication in the prevention and treatment of tuberculosis. Isoniazid is known to have a biphasic effect on the inhibition–induction of CYP2E1 and is also considered to be involved in isoniazid-induced hepatotoxicity. However, the full extent and mechanism of involvement of CYP2E1 in isoniazid-induced hepatotoxicity remain to be thoroughly investigated. In the current study, isoniazid was administered to wild-type and Cyp2e1-null mice to investigate the potential toxicity of isoniazid in vivo. The results revealed that isoniazid caused no hepatotoxicity in wild-type and Cyp2e1-null mice, but produced elevated serum cholesterol and triglycerides, and hepatic bile acids in wild-type mice, as well as decreased abundance of free fatty acids in wild-type mice and not in Cyp2e1-null mice. Metabolomic analysis demonstrated that production of isoniazid metabolites was elevated in wild-type mice along with a higher abundance of bile acids, bile acid metabolites, carnitine and carnitine derivatives; these were not observed in Cyp2e1-null mice. In addition, the enzymes responsible for bile acid synthesis were decreased and proteins involved in bile acid transport were significantly increased in wild-type mice. Lastly, treatment of targeted isoniazid metabolites to wild-type mice led to similar changes in cholesterol, triglycerides and free fatty acids. These findings suggest that while CYP2E1 is not involved in isoniazid-induced hepatotoxicity, while an isoniazid metabolite might play a role in isoniazid-induced cholestasis through enhancement of bile acid accumulation and mitochondria ?-oxidation. -- Highlights: ? Isoniazid metabolites were elevated only in wild-type mice. ? Isoniazid caused no hepatotoxicity in wild-type and Cyp2e1-null mice. ? Isoniazid elevated serum cholesterol and triglycerides, and hepatic bile acids. ? Bile acid transporters were significantly decreased in isoniazid-treated mice.

Cheng, Jie; Krausz, Kristopher W. [Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States)] [Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States); Li, Feng; Ma, Xiaochao [Department of Pharmacology, Toxicology and Therapeutics, The University of Kansas Medical Center, 4089 KLSIC, MS 1018, 3901 Rainbow Boulevard, Kansas City, KS 66160 (United States)] [Department of Pharmacology, Toxicology and Therapeutics, The University of Kansas Medical Center, 4089 KLSIC, MS 1018, 3901 Rainbow Boulevard, Kansas City, KS 66160 (United States); Gonzalez, Frank J., E-mail: fjgonz@helix.nih.gov [Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States)

2013-01-15

290

Functional processing and secretion of Chikungunya virus E1 and E2 glycoproteins in insect cells  

PubMed Central

Background Chikungunya virus (CHIKV) is a mosquito-borne, arthrogenic Alphavirus that causes large epidemics in Africa, South-East Asia and India. Recently, CHIKV has been transmitted to humans in Southern Europe by invading and now established Asian tiger mosquitoes. To study the processing of envelope proteins E1 and E2 and to develop a CHIKV subunit vaccine, C-terminally his-tagged E1 and E2 envelope glycoproteins were produced at high levels in insect cells with baculovirus vectors using their native signal peptides located in CHIKV 6K and E3, respectively. Results Expression in the presence of either tunicamycin or furin inhibitor showed that a substantial portion of recombinant intracellular E1 and precursor E3E2 was glycosylated, but that a smaller fraction of E3E2 was processed by furin into mature E3 and E2. Deletion of the C-terminal transmembrane domains of E1 and E2 enabled secretion of furin-cleaved, fully processed E1 and E2 subunits, which could then be efficiently purified from cell culture fluid via metal affinity chromatography. Confocal laser scanning microscopy on living baculovirus-infected Sf21 cells revealed that full-length E1 and E2 translocated to the plasma membrane, suggesting similar posttranslational processing of E1 and E2, as in a natural CHIKV infection. Baculovirus-directed expression of E1 displayed fusogenic activity as concluded from syncytia formation. CHIKV-E2 was able to induce neutralizing antibodies in rabbits. Conclusions Chikungunya virus glycoproteins could be functionally expressed at high levels in insect cells and are properly glycosylated and cleaved by furin. The ability of purified, secreted CHIKV-E2 to induce neutralizing antibodies in rabbits underscores the potential use of E2 in a subunit vaccine to prevent CHIKV infections. PMID:21762510

2011-01-01

291

Shape and size effects on the compressive strength of high-strength concrete  

Microsoft Academic Search

In this paper we investigate the influence of the shape and of the size of the specimens on the compressive strength of high-strength concrete. We use cylinders and cubes of different sizes for performing stable stress–strain tests. The tests were performed at a single axial strain rate, 10? 6 s? 1. This value was kept constant throughout the experimental program. Our

J. R. del Viso; J. R. Carmona; G. Ruiz

2008-01-01

292

The effect of electrically induced strength training on triceps brachii strength in untrained females  

Microsoft Academic Search

Twenty?seven apparently healthy females volunteered for a study to compare the effect of neuro?muscular electrical stimulation (NMES) (N = 7), traditional isotonic weight training (N =9) and NMES combined with isotonic weight training (N =11) on triceps brachii strength. Strength was measured isotonically (1?RM) and isometrically (MVIC). The NMES group received NMES 3 times per week. The Weight and Weight\\/NMES

Kami N. Prince; Lawrence A. Golding; Richard D. Tandy

1998-01-01

293

Effects of end conditions on compressive strength and static elastic modulus of very high strength concrete  

Microsoft Academic Search

The use of bonded and unbonded caps in testing very high strength concrete cylinders has been investigated experimentally. A hundred and ninety-two concrete cylinder specimens of 150-mm diameter and 300-mm height were cast and tested using packing with softboard, neat cement paste, neoprene pad and sulfur mortar. The design strength level of 75–100 MPa was achieved using water-cementitious material ratios

Mehmet Geso?lu; Erhan Güneyisi; Turan Özturan

2002-01-01

294

Effect of Lack of Penetration on the fatigue strength of high strength steel butt weld  

Microsoft Academic Search

Fatigue tests are performed to evaluate the fatigue strength of high strength steel containing partial penetration butt weld\\u000a and full penetration butt weld. The influence of the unwelded ligament (Lack of Penetration) in the partial penetration welds\\u000a on the fatigue life is analyzed for various LOP sizes. For full penetration welds, the fatigue crack initiated at the weld\\u000a toe and

Sungho Kim; Keunchan Jin; Wan Sung; Soowoo Nam

1994-01-01

295

Rock strength under confined shock conditions  

SciTech Connect

This report addresses the laboratory measurements of the static strength of rock needed to simulate the response of rock to an underground explosion. The approach is to identify the variables that affect the strength of rock and to discuss each effect in terms of the underlying processes that cause it. Most of the report is the result of a literature review, although some new analyses and concepts are presented. Attention is directed at three basic rock types: low porosity brittle rock such as granodiorite, high porosity brittle rock such as volcanic tuff, and a rock that may be ductile under the relevant conditions, salt. These three rock types are sufficiently different that somewhat different constitutive laws may have to be used to model their behavior.

Scholz, C.H.

1982-10-01

296

High Strength, Molecularly Thin Nanoparticle Membranes  

NASA Astrophysics Data System (ADS)

The unique strength observed in molecular thin films consisting of assemblies of nanoparticles encoded with short organic chains opens an intriguing new realm of controllable materials. Here the fundamental mechanisms underlying this unique mechanical strength are probed by molecular dynamics simulations. Using nanoparticles encoded with short hydrocarbon chains, we show that the mechanical response and failure of single nanoparticle thick membranes depend on subtle changes of the coating. Extremely high moduli were observed in agreement with experiment. We calculate Young's modulus for the membrane system based on properties of the individual components and find that ligand end-group interactions explain the observed changes in mechanical properties. Specifically, for dodecanethiol chains on 6 nm diameter gold cores, Young's modulus is 2.5 GPa for CH3 terminated chains and increases by 50% when end groups are replaced by COOH.

Salerno, K. Michael; Bolintineanu, Dan S.; Lane, J. Matthew D.; Grest, Gary S.

2014-12-01

297

Strength of Footing with Punching Shear Preventers  

PubMed Central

The punching shear failure often governs the strength of the footing-to-column connection. The punching shear failure is an undesirable failure mode, since it results in a brittle failure of the footing. In this study, a new method to increase the strength and ductility of the footing was proposed by inserting the punching shear preventers (PSPs) into the footing. The validation and effectiveness of PSP were verified through a series of experimental studies. The nonlinear finite element analysis was then performed to demonstrate the failure mechanism of the footing with PSPs in depth and to investigate the key parameters that affect the behavior of the footing with PSPs. Finally, the design recommendations for the footing with PSPs were suggested. PMID:25401141

Lee, Sang-Sup; Moon, Jiho; Park, Keum-Sung; Bae, Kyu-Woong

2014-01-01

298

Strength of footing with punching shear preventers.  

PubMed

The punching shear failure often governs the strength of the footing-to-column connection. The punching shear failure is an undesirable failure mode, since it results in a brittle failure of the footing. In this study, a new method to increase the strength and ductility of the footing was proposed by inserting the punching shear preventers (PSPs) into the footing. The validation and effectiveness of PSP were verified through a series of experimental studies. The nonlinear finite element analysis was then performed to demonstrate the failure mechanism of the footing with PSPs in depth and to investigate the key parameters that affect the behavior of the footing with PSPs. Finally, the design recommendations for the footing with PSPs were suggested. PMID:25401141

Lee, Sang-Sup; Moon, Jiho; Park, Keum-Sung; Bae, Kyu-Woong

2014-01-01

299

On the Ultimate Strength of Condensed Matter  

NASA Astrophysics Data System (ADS)

This and an accompanying paper track a range of thresholds for the response of condensed matter under loading in compression, from the ambient state to the point at which the material bond strength is overcome and it becomes warm dense matter. The threshold considered here is the weak shock limit that differentiates weak- from strong shock dynamic loading. This work examines this threshold and shows a correlation with the theoretical strength of the material. The structure of the shock that evolves has steady and unsteady phases that sweep different regions in a target in differing manners. This is put in context with scale to show it as a transit to a hydrodynamic regime. Limits on the applicability of solid mechanics are discussed in relation to the mechanisms observed.

Bourne, Neil K.

2014-07-01

300

Cryogenic evaluation of epoxy bond strength  

NASA Astrophysics Data System (ADS)

The purpose of the work presented here was to determine methods of optimizing the adhesion of a particular epoxy (CTD-101K, Composite Technology Development Inc.) to a particular nickel-based alloy substrate (Incoloy ® 908, Inco Alloys International) for cryogenic applications. Initial efforts were focused on surface preparation of the substrate material via various mechanical and chemical cleaning techniques. Test samples, fabricated to simulate the conduit-to-insulation interface, were put through a mock heat treat and vacuum/pressure impregnation process. Samples were compression/shear load tested to compare the bond strengths at room temperature and liquid nitrogen temperature. The resulting data indicate that acid etching creates a higher bond strength than the other tested techniques and that the bond formed is stronger at cryogenic temperatures than at room temperature. A description of the experiment along with the resulting data is presented here.

Albritton, N.; Young, W.

301

Cryogenic insulation strength and bond tester  

NASA Technical Reports Server (NTRS)

A method and apparatus for testing the tensile strength and bonding strength of sprayed-on foam insulation attached to metal cryogenic fuel tanks is described. A circular cutter is used to cut the insulation down to the surface of the metal tank to form plugs of the insulation for testing in situ on the tank. The apparatus comprises an electromechanical pulling device powered by a belt battery pack. The pulling device comprises a motor driving a mechanical pulling structure comprising a horizontal shaft connected to two bell cracks which are connected to a central member. When the lower end of member is attached to a fitting, which in turn is bonded to a plug, a pulling force is exerted on the plug sufficient to rupture it. The force necessary to rupture the plug or pull it loose is displayed as a digital read-out.

Schuerer, P. H.; Ehl, J. H.; Prasthofer, W. P. (inventors)

1985-01-01

302

Preventing Strength Loss of Unbleached Kraft Pulp  

SciTech Connect

Kraft pulp fibers lose inter-fiber bonding ability when they are dried during the manufacture of paper. Adverse environmental consequences of this loss include (a) limitations on the number of times that kraft fibers can be recycled, (b) reduced paper strength, sometimes making it necessary to use heavier paper or paperboard to meet product strength requirements, increasing the usage of raw materials, (c) decreased rates of paper production in cases where the fiber furnish has been over-refined in an attempt to regain inter-fiber bonding ability. The present study is the first of its type to focus on unbleached kraft fibers, which are a main ingredient of linerboard for corrugated containers. About 90 million tons of unbleached kraft fiber are used worldwide every year for this purpose.

Martin Hubbe; Richard Venditti; John Heitmann

2003-04-16

303

Dynamic strength of tantalum under impact  

NASA Astrophysics Data System (ADS)

Two sets of plane impact experiments were carried out on tantalum targets (1-2 mm thick): shock re-shock and shock-rarefaction. Some of the experiments were with and some without a LiF window. VISAR diagnostics was used to measure free surface velocity or particle velocity. The VISAR information was utilized to study the equation of state and dynamic strength of tantalum under compression and tension. The Hugoniot pressures in the experiments were roughly 6, 13, and 34 GPa. Coupling between 1d hydrodynamic simulation and a calibrated Zerilli-Armstrong model reproduces the experimental results fairly well. Spall strength extracted from pull back velocity yields a relatively high value of 6.3-6.5 GPa with negligible pressure dependence.

Glam, B.; Werdiger, M.; Horovitz, Y.; Moshe, E.; Pistinner, S. L.

2014-05-01

304

The failure strengths of perfect diamond crystals  

NASA Technical Reports Server (NTRS)

Finite elasticity analysis is extended to the 110 direction, where off axis strain symmetry is not present, and the third order elastic data are obtained for diamond. The compressive yield strengths of perfect diamond crystals loaded in the 100, 110, and 111 directions are predicted to be 2.2, 5.6, and 2.8 Mbars, respectively, while the corresponding tensile fracture strengths are 1.0, 0.5, and 0.5 Mbars. From these results and from Hertz theory it is predicted that ring fracture of spherically tipped diamonds pressed against a flat will occur at pressures of 1.8-1.9 Mbars, substantially below the yield pressure (above 3 Mbars). Modification of the tip shape leads to a predicted increase in the pressure at which fracture occurs.

Whitlock, J.; Ruoff, A. L.

1981-01-01

305

Strength of Polysilicon for MEMS Devices  

SciTech Connect

The safe, secure and reliable application of Microelectromechanical Systems (MEMS) devices requires knowledge about the distribution in material and mechanical properties of the small-scale structures. A new testing program at Sandia is quantifying the strength distribution using polysilicon samples that reflect the dimensions of critical MEMS components. The strength of polysilicon fabricated at Sandia's Microelectronic Development Laboratory was successfully measured using samples 2.5 microns thick, 1.7 microns wide with lengths between 15 and 25 microns. These tensile specimens have a freely moving hub on one end that anchors the sample to the silicon die and allows free rotation. Each sample is loaded in uniaxial tension by pulling laterally with a flat tipped diamond in a computer-controlled Nanoindenter. The stress-strain curve is calculated using the specimen cross section and gage length dimensions verified by measuring against a standard in the SEM.

Buchheit, Thomas E.; LaVan, David A.

1999-07-20

306

Nanoconfinement and the strength of biopolymers.  

PubMed

This review examines size effects observed in the mechanical strength of biopolymers that are organized in microstructures such as fibrils, layered composites, or particle nanocomposites. We review the most important aspects that connect nanoconfinement of basic material constituents at critical length scales to the mechanical performance of the entire material system: elastic modulus, strength, extensibility, and robustness. We outline theoretical and computational analysis as well as experimentation by emphasizing two strategies found in abundant natural materials: confined fibrils as part of fibers and confined mineral platelets that transfer load through a biopolymer interface in nanocomposites. We also discuss the application of confinement as a mechanism to tailor specific material properties in biological systems. PMID:23654307

Giesa, Tristan; Buehler, Markus J

2013-01-01

307

Elasticity and Strength of Biomacromolecular Crystals: Lysozyme  

NASA Technical Reports Server (NTRS)

The static Young modulus, E = 0.1 to 0.5 GPa, the crystal critical strength (sigma(sub c)) and its ratio to E,sigma(sub c)/E is approximately 10(exp 3), were measured for the first time for non cross-linked lysozyme crystals in solution. By using a triple point bending apparatus, we also demonstrated that the crystals were purely elastic. Softness of protein crystals built of hard macromolecules (26 GPa for lysozyme) is explained by the large size of the macromolecules as compared to the range of intermolecular forces and by the weakness of intermolecular bonds as compared to the peptide bond strength. The relatively large reported dynamic elastic moduli (approximately 8 GPa) from resonance light scattering should come from averaging over the moduli of intracrystalline water and intra- and intermolecular bonding.

Holmes, A. M.; Witherow, W. K.; Chen, L. Q.; Chernov, A. A.

2003-01-01

308

Cytochrome p450 2E1 polymorphisms and the risk of gastric cardia cancer  

PubMed Central

AIM: Genetic polymorphisms of drug-metabolizing enzymes have recently been shown to affect susceptibility to chemical carcinogenesis. Cytochrome P450 2E1 (CYP2E1) enzyme catalyzes the metabolism of many procarcinogens, such as N-nitrosamines and related compounds. The gene coding for this enzyme is polymorphic and thus may play a role in gastric cardia cancer (GCC) etiology. In this hospital-based case-control study, we evaluate the relationship between genetic polymorphisms of CYP2E1 and the risk of GCC. METHODS: The study subjects comprised 159 histologically confirmed GCC cases identified via hospital cancer registry and surgical records at five hospitals in Fuzhou, Fujian Province, China, between April and November 2001. Controls were 192 patients admitted to the same hospitals for nonmalignant conditions. The genotypes of CYP2E1 were detected by a PCR-based RFLP assay. The odds ratios were estimated by logistic regression analyses and were adjusted for potential confounding factors. RESULTS: The distribution of three genotypes of CYP2E1 in GCC cases and controls was significantly different (?2 = 16.04, P<0.01). The frequency of the CYP2E1 (c1/c1) genotype in GCC cases and controls was 60.4% and 40.1%, respectively. The CYP2E1 (c1/c1) genotype was associated with an increased risk for GCC (the adjusted (OR) was 2.37, 95% confidence interval (CI): 1.52-3.70). Subjects who carried the CYP2E1 (c1/c1) genotype and were habitual smokers were at a significantly higher risk of developing GCC (OR = 4.68, 95%CI: 2.19-10.04) compared with those who had the CYP2E1 (c1/c2 or c2/c2) genotype and did not smoke. CONCLUSION: These results suggest that the CYP2E1 genotype may influence individual susceptibility to development of GCC, and that the risk increases significantly in smokers. PMID:15793883

Cai, Lin; Zheng, Zong-Li; Zhang, Zuo-Feng

2005-01-01

309

CYP2E1 potentiates binge alcohol-induced gut leakiness, steatohepatitis and apoptosis  

PubMed Central

Ethanol-inducible cytochrome P450 2E1 (CYP2E1) contributes to increased oxidative stress and steatosis in chronic alcohol-exposure models. However, its role in binge ethanol-induced gut leakiness and hepatic injury is unclear. This study was aimed to investigate the role of CYP2E1 in binge alcohol-induced gut leakiness and the mechanisms of steatohepatitis. Female wild-type (WT) and Cyp2e1-null mice were treated with three doses of binge ethanol (WT-EtOH or Cyp2e1-null-EtOH) (6 g/kg oral gavage at 12-h intervals) or dextrose (negative control). Intestinal histology of only WT-EtOH exhibited epithelial alteration and blebbing of lamina propria while liver histology obtained at 6 h after the last ethanol dose showed elevated steatosis with scattered inflammatory foci. These were accompanied by increased levels of serum endotoxin, hepatic enterobacteria and triglycerides. All these changes including the intestinal histology and hepatic apoptosis, determined by TUNEL assay, were significantly reversed when WT-EtOH mice were treated with the specific inhibitor of CYP2E1 chlormethiazole and the antioxidant N-acetyl-cysteine, both of which suppressed the oxidative markers including intestinal CYP2E1. WT-EtOH also exhibited elevated amounts of serum TNF-?, hepatic cytokines, CYP2E1 and lipid peroxidation with decreased levels of mitochondrial superoxide dismutase and suppressed aldehyde dehydrogenase 2 activity. Increased hepatocyte apoptosis with elevated levels of pro-apoptotic proteins and decreased levels of active (phosphorylated) p-AKT, p-AMPK and peroxisome proliferator-activated receptor-alpha (PPAR-?), all of which are involved in fat metabolism and inflammation, were observed in WT-EtOH. These changes were significantly attenuated in the corresponding Cyp2e1-null-EtOH mice. These data indicate that both intestinal and hepatic CYP2E1 induced by binge alcohol seem critical in the binge alcohol-mediated increased nitroxidative stress, gut leakage, endotoxemia, and altered fat metabolism, and inflammation, contributing to hepatic apoptosis and steatohepatitis. PMID:24064383

Abdelmegeed, Mohamed A.; Banerjee, Atrayee; Jang, Sehwan; Yoo, Seong-Ho; Yun, Jun-Won; Gonzalez, Frank J.; Keshavarzian, Ali; Song, Byoung-Joon

2013-01-01

310

Factors Influencing the Fatigue Strength of Materials  

NASA Technical Reports Server (NTRS)

A number of factors are considered which influence the static and fatigue strength of materials under practical operating conditions as contrasted with the relations obtaining under conditions of the usual testing procedure. Such factors are interruptions in operation, periodically fluctuating stress limits and mean stresses with periodic succession of several groups and stress states, statistical changes and succession of stress limits and mean stresses, frictional corrosion at junctures, and notch effects.

Bollenrath, F

1941-01-01

311

Isometric strength and occupational muscle disorders  

Microsoft Academic Search

Summary  In two longitudinal studies, initial muscle strength and endurance of the shoulderforearm muscles were related to deterioration of shoulder-neck-arm disorders after one year. Group I (n=32) worked in the automobile industry assembling car motors. Their work was performed when standing and walking, and implied varied postures and exertion of external forces. Group II (n=96) worked in the electronics industry assembling

Åsa Kilbom

1988-01-01

312

Isometric exercise, isometric strength and anthropometric measurements  

Microsoft Academic Search

Summary  \\u000a1. \\u000a29 young adult male subjects practiced 15 sec. of maximal isometric contractions of the elbow flexors three times a day, 5 days a week, for 5 weeks. They achieved greater increases in strength than have been claimed for a single two-thirds maximal contraction once a day, although the latter has been said to provide the maximal stimulus for

Philip J. Rasch; William R. Pierson

1963-01-01

313

Residual strength of thin panels with cracks  

NASA Astrophysics Data System (ADS)

The previous design philosophies involving safe life, fail-safe and damage tolerance concepts become inadequate for assuring the safety of aging aircraft structures. For example, the failure mechanism for the Aloha Airline accident involved the coalescence of undetected small cracks at the rivet holes causing a section of the fuselage to peel open during flight. Therefore, the fuselage structure should be designed to have sufficient residual strength under worst case crack configurations and in-flight load conditions. Residual strength is interpreted as the maximum load carrying capacity prior to unstable crack growth. Internal pressure and bending moment constitute the two major components of the external loads on the fuselage section during flight. Although the stiffeners in the form of stringers, frames and tear straps sustain part of the external loads, the significant portion of the load is taken up by the skin. In the presence of a large crack in the skin, the crack lips bulge out with considerable yielding; thus, the geometric and material nonlinearities must be included in the analysis for predicting residual strength. Also, these nonlinearities do not permit the decoupling of in-plane and out-of-plane bending deformations. The failure criterion combining the concepts of absorbed specific energy and strain energy density addresses the aforementioned concerns. The critical absorbed specific energy (local toughness) for the material is determined from the global specimen response and deformation geometry based on the uniaxial tensile test data and detailed finite element modeling of the specimen response. The use of the local toughness and stress-strain response at the continuum level eliminates the size effect. With this critical parameter and stress-strain response, the finite element analysis of the component by using STAGS along with the application of this failure criterion provides the stable crack growth calculations for residual strength predictions.

Madenci, Erdogan

1994-12-01

314

Shear adhesion strength of aligned electrospun nanofibers.  

PubMed

Inspiration from nature such as insects' foot hairs motivates scientists to fabricate nanoscale cylindrical solids that allow tens of millions of contact points per unit area with material substrates. In this paper, we present a simple yet robust method for fabricating directionally sensitive shear adhesive laminates. By using aligned electrospun nylon-6, we create dry adhesives, as a succession of our previous work on measuring adhesion energies between two single free-standing electrospun polymer fibers in cross-cylinder geometry, randomly oriented membranes and substrate, and peel forces between aligned fibers and substrate. The synthetic aligned cylindrical solids in this study are electrically insulating and show a maximal Mode II shear adhesion strength of 27 N/cm(2) on a glass slide. This measured value, for the purpose of comparison, is 270% of that reported from gecko feet. The Mode II shear adhesion strength, based on a commonly known "dead-weight" test, is 97-fold greater than the Mode I (normal) adhesion strength of the same. The data indicate a strong shear binding on and easy normal lifting off. Anisotropic adhesion (Mode II/Mode I) is pronounced. The size and surface boundary effects, crystallinity, and bending stiffness of fibers are used to understand these electrospun nanofibers, which vastly differ from otherwise known adhesive technologies. The anisotropic strength distribution is attributed to a decreasing fiber diameter and an optimized laminate thickness, which, in turn, influences the bending stiffness and solid-state "wettability" of points of contact between nanofibers and surface asperities. PMID:25105533

Najem, Johnny F; Wong, Shing-Chung; Ji, Guang

2014-09-01

315

The strength of hard-rock pillars  

Microsoft Academic Search

Observations of pillar failures in Canadian hard-rock mines indicate that the dominant mode of failure is progressive slabbing and spalling. Empirical formulas developed for the stability of hard-rock pillars suggest that the pillar strength is directly related to the pillar width-to-height ratio and that failure is seldom observed in pillars where the width-to-height ratio is greater than 2. Two-dimensional finite

C. d. Martin; W. g. Maybee

2000-01-01

316

Sex Differences in Tibial Bone Strength  

NASA Technical Reports Server (NTRS)

We have used an instrument (MRTA or Mechanical Response Tissue Analyzer) that measures bending stiffness (EI) non-Invasively to evaluate the strength of the tibia, a long bone in the weightbearing skeleton highly vulnerable to mineral loss during space flight. In healthy men, we found asymmetry in EI consistent with the bone's support function (L greater than R). In this study, we analyzed EI in women and compared the results to those in men.

Arnaud, Sara B.; Hutchinson, T. M.; Torikoshi, S.; Hutchinson, K. J.; Hargens, Alan R.; Steele, C. R.

1995-01-01

317

Oscillator strengths for ionized iron and manganese  

NASA Technical Reports Server (NTRS)

The observed strengths of interstellar absorption lines of Fe II and Mn II in the spectra of alpha Vir, beta Cen, pi Sco, and zeta Oph along with laboratory f values of some of these lines between 2343 and 2606 A have been used to determine curves of growth for these ions and the f-values of ten lines of Fe II and three lines of Mn II between 1055 and 1261 A. The Fe and Mn abundances are derived.

De Boer, K. S.; Pottasch, S. R.; Morton, D. C.; York, D. G.

1974-01-01

318

Residual strength of thin panels with cracks  

NASA Technical Reports Server (NTRS)

The previous design philosophies involving safe life, fail-safe and damage tolerance concepts become inadequate for assuring the safety of aging aircraft structures. For example, the failure mechanism for the Aloha Airline accident involved the coalescence of undetected small cracks at the rivet holes causing a section of the fuselage to peel open during flight. Therefore, the fuselage structure should be designed to have sufficient residual strength under worst case crack configurations and in-flight load conditions. Residual strength is interpreted as the maximum load carrying capacity prior to unstable crack growth. Internal pressure and bending moment constitute the two major components of the external loads on the fuselage section during flight. Although the stiffeners in the form of stringers, frames and tear straps sustain part of the external loads, the significant portion of the load is taken up by the skin. In the presence of a large crack in the skin, the crack lips bulge out with considerable yielding; thus, the geometric and material nonlinearities must be included in the analysis for predicting residual strength. Also, these nonlinearities do not permit the decoupling of in-plane and out-of-plane bending deformations. The failure criterion combining the concepts of absorbed specific energy and strain energy density addresses the aforementioned concerns. The critical absorbed specific energy (local toughness) for the material is determined from the global specimen response and deformation geometry based on the uniaxial tensile test data and detailed finite element modeling of the specimen response. The use of the local toughness and stress-strain response at the continuum level eliminates the size effect. With this critical parameter and stress-strain response, the finite element analysis of the component by using STAGS along with the application of this failure criterion provides the stable crack growth calculations for residual strength predictions.

Madenci, Erdogan

1994-01-01

319

Atomic Oscillator Strengths In The Vacuum Ultraviolet  

NASA Astrophysics Data System (ADS)

Transitionsin singly-ionized and doubly-ionized iron-group elements give rise to prominent emission lines from a wide variety of astrophysical objects. Although the database of experimental oscillator strengths of Fe II has also been greatly extended by the FERRUM project, few experimental oscillator strengths are available in the region below 1600 Å, where many levels that give rise to emission lines at longer wavelengths have their dominant decays. The established way to measure accurate oscillator strengths for atomic lines combines the measurement of a lifetime of an upper energy level with a separate measurement of the branching fractions of all the lines emitted from that level. This technique relies on being able to observe all the spectral lines emitted by the upper level, which range down to Ly-? or below for many fluorescence lines. We have developed techniques to measure branching fractions in the vacuum ultraviolet using our 10.7-m normal incidence grating spectrograph. For this we use phosphor image plates as replacements for the photographic plates previously used on this instrument. Image plates are sensitive to wavelengths from the X-ray region to 2200 Å, and have a linear intensity response with a dynamic range of at least 10000. We have recorded spectra of iron-neon hollow cathode and Penning discharges, using a deuterium standard lamp for radiometric calibration. We will present the first measurements of oscillator strengths using this technique. We are also investigating methods of radiometric calibration below 1150 Å using hollow cathode standard lamps. This will enable us to measure branching ratios down to 800 Å or below. This work is partially funded by NASA under the inter-agency agreement W-10,255.

Nave, Gillian; Sansonetti, C. J.; Szabo, C. I.

2008-05-01

320

Effective adhesion strength of specifically bound vesicles  

E-print Network

A theoretical approach has been undertaken in order to model the thermodynamic equilibrium of a vesicle adhering to a flat substrate. The vesicle is treated in a canonical description with a fixed number of sites. A finite number of these sites are occupied by mobile ligands that are capable of interacting with a discrete number of receptors immobilized on the substrate. Explicit consideration of the bending energy of the vesicle shape has shown that the problem of the vesicle shape can be decoupled from the determination of the optimum allocation of ligands over the vesicle. The allocation of bound and free ligands in the vesicle could be determined as a function of the size of the contact zone, the ligand-receptor binding strength and the concentration of the system constituents. Several approximate solutions for different regions of system parameters are determined and in particular, the distinction between receptor-dominated equilibria and ligand-dominated equilibria is found to be important. The crossover between these two types of solutions is found to occur at a critical size of the contact zone. The presented approach enables the calculation of the effective adhesion strength of the vesicle and thus permits meaningful comparisons with relevant experiments as well as connecting the presented model with the proven success of the continuum approach for modeling the shapes of adhering vesicles. The behavior of the effective adhesion strength is analyzed in detail and several approximate expressions for it are given.

Ana-Suncana Smith; Udo Seifert

2005-02-15

321

Ordering design tasks based on coupling strengths  

NASA Technical Reports Server (NTRS)

The design process associated with large engineering systems requires an initial decomposition of the complex system into modules of design tasks which are coupled through the transference of output data. In analyzing or optimizing such a coupled system, it is essential to be able to determine which interactions figure prominently enough to significantly affect the accuracy of the system solution. Many decomposition approaches assume the capability is available to determine what design tasks and interactions exist and what order of execution will be imposed during the analysis process. Unfortunately, this is often a complex problem and beyond the capabilities of a human design manager. A new feature for DeMAID (Design Manager's Aid for Intelligent Decomposition) will allow the design manager to use coupling strength information to find a proper sequence for ordering the design tasks. In addition, these coupling strengths aid in deciding if certain tasks or couplings could be removed (or temporarily suspended) from consideration to achieve computational savings without a significant loss of system accuracy. New rules are presented and two small test cases are used to show the effects of using coupling strengths in this manner.

Rogers, James L., Jr.; Bloebaum, Christina L.

1994-01-01

322

Ordering Design Tasks Based on Coupling Strengths  

NASA Technical Reports Server (NTRS)

The design process associated with large engineering systems requires an initial decomposition of the complex system into modules of design tasks which are coupled through the transference of output data. In analyzing or optimizing such a coupled system, it is essential to be able to determine which interactions figure prominently enough to significantly affect the accuracy of the system solution. Many decomposition approaches assume the capability is available to determine what design tasks and interactions exist and what order of execution will be imposed during the analysis process. Unfortunately, this is often a complex problem and beyond the capabilities of a human design manager. A new feature for DeMAID (Design Manager's Aid for Intelligent Decomposition) will allow the design manager to use coupling strength information to find a proper sequence for ordering the design tasks. In addition, these coupling strengths aid in deciding if certain tasks or couplings could be removed (or temporarily suspended) from consideration to achieve computational savings without a significant loss of system accuracy. New rules are presented and two small test cases are used to show the effects of using coupling strengths in this manner.

Rogers, J. L.; Bloebaum, C. L.

1994-01-01

323

Surface bond strength in nickel based alloys.  

PubMed

Bonding of ceramic to the alloy is essential for the longevity of porcelain fused to metal restorations. Imported alloys used now a days in processing them are not economical. So this study was conducted to evaluate and compare the bond strength of ceramic material to nickel based cost effective Nonferrous Materials Technology Development Center (NFTDC), Hyderabad and Heraenium S, Heraeus Kulzer alloy. An Instron testing machine, which has three-point loading system for the application of load onto the specimen was utilized for analyzing bond strength of both alloys. Student t test was conducted and t value obtained was 0.644, and the mean value of flexural bond strength of indigenous alloy is 81.75 with standard deviation of 12.25 and of imported alloy is 84.42 with standard deviation of 10.35, indicating that there was no significant difference between the two alloys. Due to ever increasing cost of imported non-precious alloy the need for a cost-effective replacement was fulfilled by indigenous NFTDC alloy. PMID:24431791

Ramesh, Ganesh; Padmanabhan, T V; Ariga, Padma; Joshi, Shalini; Bhuminathan, S; Vijayaraghavan, Vasantha

2013-12-01

324

Strength of a bifurcated H bond  

PubMed Central

Macromolecules are characterized by their particular arrangement of H bonds. Many of these interactions involve a single donor and acceptor pair, such as the regular H-bonding pattern between carbonyl oxygens and amide H+s four residues apart in ?-helices. The H-bonding potential of some acceptors, however, leads to the phenomenon of overcoordination between two donors and one acceptor. Herein, using isotope-edited Fourier transform infrared measurements and density functional theory (DFT) calculations, we measured the strength of such bifurcated H bonds in a transmembrane ?-helix. Frequency shifts of the 13C=18O amide I mode were used as a reporter of the strength of the bifurcated H bond from a thiol and hydroxyl H+ at residue i + 4. DFT calculations yielded very similar frequency shifts and an energy of ?2.6 and ?3.4 kcal/mol for the thiol and hydroxyl bifurcated H bonds, respectively. The strength of the intrahelical bifurcated H bond is consistent with its prevalence in hydrophobic environments and is shown to significantly impact side-chain rotamer distribution. PMID:24591597

Feldblum, Esther S.; Arkin, Isaiah T.

2014-01-01

325

Bacterial cellulose gels with high mechanical strength.  

PubMed

A composite structure was formed between polyethylene glycol diacrylate (PEGDA) and bacterial cellulose (BC) gels swollen in polyethylene glycol (PEG) as a solvent (BC/PEG gel) to improve the mechanical strength of the gels. The mechanical strength under compression and the rheostatic properties of the gels were evaluated. The compression test results indicated that the mechanical strength of the gels depended on the weight percent of cross-linked PEGDA in the gel, the chain length between the cross-linking points, and the cross-linking density of PEGDA polymers. The PEGDA polymers around the cellulose fibers were resistant to pressure; thus, the BC/PEG-PEGDA gel was stronger than the BC/PEG gel under compression. The results of transmittance measurements and thermomechanical analysis showed that the rheostatic properties of the gels were retained even after composite structure formation. BC/PEG-PEGDA gels, which are expected to be biocompatible, may be useful for clinical applications as a soft material. PMID:25492172

Numata, Yukari; Sakata, Tadanori; Furukawa, Hidemitsu; Tajima, Kenji

2015-02-01

326

Polymerization shrinkage influences microtensile bond strength.  

PubMed

Shrinkage results from a complex spatial strain network, producing movements within materials. The purpose of this study was to test whether microtensile bond strength (microTBS) of a light-curing resin composite to enamel depends on distance to the center of the curing mass. Labial surfaces of bovine incisors were ground flat, divided into 2 groups (n = 8), acid-etched, and coated with an unfilled resin bond. A resin-based composite was placed in one increment (group A) or separately at gingival, central, and incisal sites (group B), and light-cured. Teeth were sectioned, yielding stick-shaped specimens assigned to one of 9 groups according to distance to incisal edge of restoration (NDistanc). Microtensile bond strength was transformed to percentages of its maximum values within each tooth (PMPa). Comparisons within groups showed (group A) that mean PMPa decreased from central to gingival and from central to incisal (p < 0.01). Comparisons between groups showed that mean PMPa was significantly lower in group A compared with group B, only at gingival and incisal sites. Microtensile bond strength significantly decreased as the distance increased to the center of the curing mass. PMID:17314253

Cabrera, E; de la Macorra, J C

2007-03-01

327

U-Groove Aluminum Weld Strength Improvement  

NASA Technical Reports Server (NTRS)

Though butt-welds are among the most preferred joining methods in aerostructures, their strength dependence on inelastic mechanics is generally the least understood. This study investigated experimental strain distributions across a thick aluminum U-grooved weld and identified two weld process considerations for improving the multipass weld strength. One is the source of peaking in which the extreme thermal expansion and contraction gradient of the fusion heat input across the groove tab thickness produces severe angular distortion that induces bending under uniaxial loading. The other is the filler strain hardening decreasing with increasing filler pass sequences, producing the weakest welds on the last weld pass side. Both phenomena are governed by weld pass sequences. Many industrial welding schedules unknowingly compound these effects, which reduce the weld strength. A depeaking index model was developed to select filler pass thickness, pass numbers, and sequences to improve depeaking in the welding process. The result was to select the number and sequence of weld passes to reverse the peaking angle such as to combine the strongest weld pass side with the peaking induced bending tension component side to provide a more uniform stress and stronger weld under axial tensile loading.

Verderaime, V.; Vaughan, R.

1997-01-01

328

ZERODUR: bending strength data for etched surfaces  

NASA Astrophysics Data System (ADS)

In a continuous effort since 2007 a considerable amount of new data and information has been gathered on the bending strength of the extremely low thermal expansion glass ceramic ZERODUR®. By fitting a three parameter Weibull distribution to the data it could be shown that for homogenously ground surfaces minimum breakage stresses exist lying much higher than the previously applied design limits. In order to achieve even higher allowable stress values diamond grain ground surfaces have been acid etched, a procedure widely accepted as strength increasing measure. If surfaces are etched taking off layers with thickness which are comparable to the maximum micro crack depth of the preceding grinding process they also show statistical distributions compatible with a three parameter Weibull distribution. SCHOTT has performed additional measurement series with etch solutions with variable composition testing the applicability of this distribution and the possibility to achieve further increase of the minimum breakage stress. For long term loading applications strength change with time and environmental media are important. The parameter needed for prediction calculations which is combining these influences is the stress corrosion constant. Results from the past differ significantly from each other. On the basis of new investigations better information will be provided for choosing the best value for the given application conditions.

Hartmann, Peter; Leys, Antoine; Carré, Antoine; Kerz, Franca; Westerhoff, Thomas

2014-07-01

329

Selective replication of E1B55K-deleted adenoviruses depends on enhanced E1A expression in cancer cells  

Microsoft Academic Search

E1B55K-deleted dl1520 could selectively replicate in cancer cells and has been used in clinical trials as an antitumor agent. The mechanism of virus selective replication in cancer cells, including a possible role of p53, is unclear. Studies with established cancer cell lines have demonstrated that some cancer cells are resistant to dl1520 replication, regardless of the p53 status. Hep3B cells

X Zheng; X-M Rao; C L Snodgrass; K M McMasters; H S Zhou

2006-01-01

330

Two Mutations Impair the Stability and Function of Ubiquitin-Activating Enzyme (E1)  

PubMed Central

Protein ubiquitination plays critical roles in the regulation of multiple cellular processes including cell proliferation, signal transduction, oncogenesis and hypoxic response. TS20 is a Balb3T3-derived cell line in which ubiquitination is inhibited by restrictive temperature. While TS20 has been used to elucidate the degradation of many important proteins including p53, p27, HIF-1? and ornithine decarboxylase, the molecular basis of its temperature sensitivity has not been fully determined. We cloned full-length E1 cDNA from TS20. Sequencing analysis revealed two point mutations (nt736G to A and nt2313G to C) that lead to substitution of aa189A to T and aa714W to C, respectively. Transient transfection assays revealed that mutant E1 was less stable than its wild-type counterpart, and restrictive temperature (39°C) accelerated its degradation. Under permissive temperature, reverting aa714C to W significantly improved E1 stability and activity. Under restrictive temperature, reverting of both substitutions was required to fully restore E1 stability. Similar results were observed when the mutants were expressed in non-TS20 cells, indicating the mutations are sufficient for its temperature sensitive degradation observed in TS20 cells. Functionally, reverting aa714C to W was sufficient to facilitate the monoubiquitination of H2A and to support TS20 growth at 39°C. It also significantly improved the ubiquitination-dependent disposal of HIF-1?. Our data conclusively demonstrate that mutations introgenic to UVBE1 cause E1 instability, which leads to deficiency of E1 function. Our data establish the molecular basis for unambiguous interpretation of experimental data based on TS20 cells, and provide new insight into the structural determinants of E1 stability. PMID:21678405

Lao, Taotao; Chen, Shuyang; Sang, Nianli

2011-01-01

331

Osteogenic gene expression of murine osteoblastic (MC3T3-E1) cells under cyclic tension  

NASA Astrophysics Data System (ADS)

Low-level laser therapy (LLLT) can promote cell proliferation. The remodeling ability of the tension side of orthodontic teeth affects post-orthodontic stability. The purpose of the present study was to investigate the osteogenic effects of LLLT on osteoblast-like cells treated with a simulated tension system that provides a mechanical tension regimen. Murine osteoblastic (MC3T3-E1) cells were cultured in a Flexcell strain unit with programmed loads of 12% elongation at a frequency of 0.5?Hz for 24 and 48?h. The cultured cells were treated with a low-level diode laser using powers of 5?J and 10?J. The proliferation of MC3T3-E1 cells was determined using the Alamar Blue assay. The expression of osteogenic genes (type I collagen (Col-1), osteopontin (OPN), osteocalcin (OC), osteoprotegerin (OPG), receptor activator of nuclear factor kappa B ligand (RANKL), bone morphologic protein (BMP-2), and bone morphologic protein (BMP-4)) in MC3T3-E1 cells was analyzed using reverse transcription polymerase chain reaction (RT-PCR). The data were analyzed using one-way analysis of variance. The proliferation rate of tension-cultured MC3T3-E1 cells under 5?J and 10?J LLLT increased compared with that of the control group (p < 0.05). Prominent mineralization of the MC3T3-E1 cells was visible using a von Kossa stain in the 5?J LLLT group. Osteogenic genes (Col-1, OC, OPG and BMP-2) were significantly expressed in the MC3T3-E1 cells treated with 5?J and 10?J LLLT (p < 0.05). LLLT in tension-cultured MC3T3-E1 cells showed synergistic osteogenic effects, including increases in cell proliferation and Col-1, OPN, OC, OPG and BMP-2 gene expression. LLLT might be beneficial for bone remodeling on the tension side of orthodontics.

Kao, C. T.; Chen, C. C.; Cheong, U.-I.; Liu, S. L.; Huang, T. H.

2014-08-01

332

The adenovirus E1A protein overrides the requirement for cellular ras in initiating DNA synthesis.  

PubMed Central

The adenovirus E1A protein can induce cellular DNA synthesis in growth-arrested cells by interacting with the cellular protein p300 or pRb. In addition, serum- and growth factor-dependent cells require ras activity to initiate DNA synthesis and recently we have shown that Balb/c 3T3 cells can be blocked in either early or late G1 following microinjection of an anti-ras antibody. In this study, the E1A 243 amino acid protein is shown through microinjection not only to shorten the G0 to S phase interval but, what is more important, to override the inhibitory effects exerted by the anti-ras antibody in either early or late G1. Specifically, whether E1A is co-injected with anti-ras into quiescent cells or injected 18 h following a separate injection of anti-ras after serum stimulation, it efficiently induces cellular DNA synthesis in cells that would otherwise be blocked in G0/G1. Moreover, injection of a mutant form of E1A that can no longer associate with p300 is just as efficient as wild-type E1A in stimulating DNA synthesis in cells whose ras activity has been neutralized by anti-ras. The results presented here show that E1A is capable of overriding the requirement of cellular ras activity in promoting the entry of cells into S phase. Moreover, the results suggest the possibility that pRb and/or pRb-related proteins may function in a ras-dependent pathway that enables E1A to achieve this activity. Images PMID:7813447

Stacey, D W; Dobrowolski, S F; Piotrkowski, A; Harter, M L

1994-01-01

333

The adenovirus E1A protein overrides the requirement for cellular ras in initiating DNA synthesis.  

PubMed

The adenovirus E1A protein can induce cellular DNA synthesis in growth-arrested cells by interacting with the cellular protein p300 or pRb. In addition, serum- and growth factor-dependent cells require ras activity to initiate DNA synthesis and recently we have shown that Balb/c 3T3 cells can be blocked in either early or late G1 following microinjection of an anti-ras antibody. In this study, the E1A 243 amino acid protein is shown through microinjection not only to shorten the G0 to S phase interval but, what is more important, to override the inhibitory effects exerted by the anti-ras antibody in either early or late G1. Specifically, whether E1A is co-injected with anti-ras into quiescent cells or injected 18 h following a separate injection of anti-ras after serum stimulation, it efficiently induces cellular DNA synthesis in cells that would otherwise be blocked in G0/G1. Moreover, injection of a mutant form of E1A that can no longer associate with p300 is just as efficient as wild-type E1A in stimulating DNA synthesis in cells whose ras activity has been neutralized by anti-ras. The results presented here show that E1A is capable of overriding the requirement of cellular ras activity in promoting the entry of cells into S phase. Moreover, the results suggest the possibility that pRb and/or pRb-related proteins may function in a ras-dependent pathway that enables E1A to achieve this activity. PMID:7813447

Stacey, D W; Dobrowolski, S F; Piotrkowski, A; Harter, M L

1994-12-15

334

Structural Dissection of a Gating Mechanism Preventing Misactivation of Ubiquitin by NEDD8’s E1  

SciTech Connect

Post-translational covalent modification by ubiquitin and ubiquitin-like proteins (UBLs) is a major eukaryotic mechanism for regulating protein function. In general, each UBL has its own E1 that serves as the entry point for a cascade. The E1 first binds the UBL and catalyzes adenylation of the UBL's C-terminus, prior to promoting UBL transfer to a downstream E2. Ubiquitin's Arg 72, which corresponds to Ala72 in the UBL NEDD8, is a key E1 selectivity determinant: swapping ubiquitin and NEDD8 residue 72 identity was shown previously to swap their E1 specificity. Correspondingly, Arg190 in the UBA3 subunit of NEDD8's heterodimeric E1 (the APPBP1-UBA3 complex), which corresponds to a Gln in ubiquitin's E1 UBA1, is a key UBL selectivity determinant. Here, we dissect this specificity with biochemical and X-ray crystallographic analysis of APPBP1-UBA3-NEDD8 complexes in which NEDD8's residue 72 and UBA3's residue 190 are substituted with different combinations of Ala, Arg, or Gln. APPBP1-UBA3's preference for NEDD8's Ala72 appears to be indirect, due to proper positioning of UBA3's Arg190. By contrast, our data are consistent with direct positive interactions between ubiquitin's Arg72 and an E1's Gln. However, APPBP1-UBA3's failure to interact with a UBL having Arg72 is not due to a lack of this favorable interaction, but rather arises from UBA3's Arg190 acting as a negative gate. Thus, parallel residues from different UBL pathways can utilize distinct mechanisms to dictate interaction selectivity, and specificity can be amplified by barriers that prevent binding to components of different conjugation cascades.

Souphron,J.; Waddell, M.; Paydar, A.; Tokgöz-Gromley, Z.; Roussel, M.; Schulman, B.

2008-01-01

335

Multifactorial Comparative Proteomic Study of Cytochrome P450 2E1 Function in Chronic Alcohol Administration  

PubMed Central

With the use of iTRAQ technique, a multifactorial comparative proteomic study can be performed. In this study, to obtain an overview of ethanol, CYP2E1 and gender effects on liver injury and gain more insight into the underlying molecular mechanism, mouse liver proteomes were quantitatively analyzed using iTRAQ under eight conditions including mice of different genders, wild type versus CYP2E1 knockout, and normal versus alcohol diet. A series of statistical and bioinformatic analyses were explored to simplify and clarify multifactorial comparative proteomic data. First, with the Principle Component analysis, six proteins, CYP2E1, FAM25, CA3, BHMT, HIBADH and ECHS1, involved in oxidation reduction, energy and lipid metabolism and amino acid metabolism, were identified as the most differentially expressed gene products across all of the experimental conditions of our chronic alcoholism model. Second, hierarchical clustering analysis showed CYP2E1 knockout played a primary role in the overall differential protein expression compared with ethanol and gender factors. Furthermore, pair-wise multiple comparisons have revealed that the only significant expression difference lied in wild-type and CYP2E1 knockout mice both treated with ethanol. Third, K-mean clustering analysis indicated that the CYP2E1 knockout had the reverse effect on ethanol induced oxidative stress and lipid oxidation. More importantly, IPA analysis of proteomic data inferred that the gene expressions of two upstream regulators, NRF2 and PPAR?, regulated by chronic alcohol feeding and CYP2E1 knockout, are involved in ethanol induced oxidative stress and lipid oxidation. The present study provides an effectively comprehensive data analysis strategy to compare multiple biological factors, contributing to biochemical effects of alcohol on the liver. The mass spectrometry proteomics data have been deposited to the ProteomeXchange with data set identifier of PXD000635. PMID:24658151

Wang, Yuan; Kou, Yan; Wang, Xiaodong; Cederbaum, Arthur; Wang, Rong

2014-01-01

336

Structural Dissection of a Gating Mechanism Preventing Misactivation of Ubiquitin by NEDD8’s E1  

PubMed Central

Post-translational covalent modification by ubiquitin and ubiquitin-like proteins (UBLs) is a major eukaryotic mechanism for regulating protein function. In general, each UBL has its own E1 that serves as the entry point for a cascade. The E1 first binds the UBL and catalyzes adenylation of the UBL’s C-terminus, prior to promoting UBL transfer to a downstream E2. Ubiquitin’s Arg 72, which corresponds to Ala72 in the UBL NEDD8, is a key E1 selectivity determinant: swapping ubiquitin and NEDD8 residue 72 identity was shown previously to swap their E1 specificity. Correspondingly, Arg190 in the UBA3 subunit of NEDD8’s heterodimeric E1 (the APPBP1-UBA3 complex), which corresponds to a Gln in ubiquitin’s E1 UBA1, is a key UBL selectivity determinant. Here, we dissect this specificity with biochemical and X-ray crystallographic analysis of APPBP1-UBA3-NEDD8 complexes in which NEDD8’s residue 72 and UBA3’s residue 190 are substituted with different combinations of Ala, Arg, or Gln. APPBP1-UBA3’s preference for NEDD8’s Ala72 appears to be indirect, due to proper positioning of UBA3’s Arg190. By contrast, our data are consistent with direct positive interactions between ubiquitin’s Arg72 and an E1’s Gln. However, APPBP1-UBA3’s failure to interact with a UBL having Arg72 is not due to a lack of this favorable interaction, but rather arises from UBA3’s Arg190 acting as a negative gate. Thus, parallel residues from different UBL pathways can utilize distinct mechanisms to dictate interaction selectivity, and specificity can be amplified by barriers that prevent binding to components of different conjugation cascades. PMID:18652489

2008-01-01

337

Cement bond strengths of titanium plates.  

PubMed

The success of the oral rehabilitation of implant patients depends not only on the osseointegration of implant fixtures but also on maintaining the integrity of the connection of prosthetic superstructures to these fixtures. It was an objective of the present study to evaluate and compare cement bond strengths among rolled (R), cast (C) and metal-injection-molded (M) commercially pure titanium plates which were bonded with Panavia 21 (Kuraray) and Imperva (Shofu) cements. Two plates (15x5x1 mm) of each R, C, and M were lap-jointed (lap length: 5 mm). The joints were stored in 37 degrees C distilled water for 24 h, followed by tensile tests with an INSTRON system under 1 mm/min crosshead speed. It was found that the bond strength of R with Panavia 21 (PAN) was 5.31 (SD:1.5) MPa and 2.30 (0.83) MPa with Imperva (IMP) cement. These were improved by applying an alloy primer to 7.08 (1.31) MPa and 6.72 (1.63) MPa, respectively. Using PAN with primer application, C and M samples showed bond strengths of 7.99 (1.31) and 7.20 (2.50) MPa, while they were 5.83 (2.15) and 6.79 (2.09) MPa using IMP with primer. There was a significant difference (p<0.01) between PAN and IMP cements for C samples. Additionally, samples were pre-oxidized at 100 degrees C in air for 10 min. Bond strengths of PAN with the primer were 5.69 (2.25), 9.14 (1.28), and 5.60 (3.13) MPa for R, C, and M sample groups. If the cement with the primer was applied immediately after the polishing (instead of pre-oxidized surfaces), bond strengths were improved to 9.14 (1.78) for R, 9.29 (1.85) for C, and 9.36 (1.81) MPa for M sample group. At p<0.05 level, there was a significant difference between surface pre-condition of R and M, but no significance with C. PMID:12883175

Ito, Michio; Nagasawa, Sakae; Yoshida, Takamitsu; Kamijo, Kuni; Khabbaz, Zahra; Oshida, Yoshiki

2003-01-01

338

Adenovirus E1B 19-Kilodalton Protein Modulates Innate Immunity through Apoptotic Mimicry  

PubMed Central

ABSTRACT Cells that undergo apoptosis in response to chemical or physical stimuli repress inflammatory reactions, but cells that undergo nonapoptotic death in response to such stimuli lack this activity. Whether cells dying from viral infection exhibit a cell death-type modulatory effect on inflammatory reactions is unknown. We compared the effects on macrophage inflammatory responses of cells dying an apoptotic or a nonapoptotic death as a result of adenoviral infection. The results were exactly opposite to the predictions from the conventional paradigm. Cells dying by apoptosis induced by infection with an adenovirus type 5 (Ad5) E1B 19-kilodalton (E1B 19K) gene deletion mutant did not repress macrophage NF-?B activation or cytokine responses to proinflammatory stimuli, whereas cells dying a nonapoptotic death from infection with E1B 19K-competent, wild-type Ad5 repressed these macrophage inflammatory responses as well as cells undergoing classical apoptosis in response to chemical injury. The immunorepressive, E1B 19K-related cell death activity depended upon direct contact of the virally infected corpses with responder macrophages. Replacement of the viral E1B 19K gene with the mammalian Bcl-2 gene in cis restored the nonapoptotic, immunorepressive cell death activity of virally infected cells. These results define a novel function of the antiapoptotic, adenoviral E1B 19K protein that may limit local host innate immune inflammation during accumulation of virally infected cells at sites of infection and suggest that E1B 19K-deleted, replicating adenoviral vectors might induce greater inflammatory responses to virally infected cells than E1B 19K-positive vectors, because of the net effect of their loss-of-function mutation. IMPORTANCE We observed that cells dying a nonapoptotic cell death induced by adenovirus infection repressed macrophage proinflammatory responses while cells dying by apoptosis induced by infection with an E1B 19K deletion mutant virus did not repress macrophage proinflammatory responses and enhanced some cytokine responses. Our results define a new function of the antiapoptotic, adenoviral protein E1B 19K, which we have termed “apoptotic mimicry.” Our studies suggest the possibility that the presence or absence of this E1B 19K function could alter the immunological outcome of both natural and therapeutic adenoviral infections. For example, emerging, highly immunopathogenic adenovirus serotypes might induce increased host inflammatory responses as a result of altered E1B 19K function or expression. It is also possible that engineered variations in E1B 19K expression/function could be created during adenovirus vector design that would increase the therapeutic efficacy of replicating adenovirus vectors for vaccines or oncolytic viral targeting of neoplastic cells. PMID:24352454

Grigera, Fernando; Ucker, David S.; Cook, James L.

2014-01-01

339

Antigenic structure of envelope glycoprotein E1 of hog cholera virus.  

PubMed Central

Envelope glycoprotein E1 (gp51 to gp54) is the most antigenic protein of hog cholera virus or classical swine fever virus (CSFV). Four antigenic domains, A to D, have been mapped on E1 with a panel of monoclonal antibodies (MAbs) raised against CSFV strain Brescia. The boundaries of these domains have been established by extensive studies on binding of MAbs to transiently expressed deletion mutants of E1 (P. A. van Rijn, E. J. de Meijer, H. G. P. van Gennip, and R. J. M. Moormann, J. Gen. Virol. 74:2053-2060, 1993). In this study, we used neutralizing MAbs of domains A, B, and C to isolate MAb-resistant mutants (MAR mutants) of CSFV strain Brescia and Chinese vaccine strain ("C"). The E1 genes of MAR mutants were cloned in a eukaryotic expression vector, and the effects of MAR mutations on epitopes were studied with a panel of 19 MAbs by immunostaining of COS1 cells transiently expressing these mutant E1s. Except for the MAR mutation Cys-->Arg at position 792, which abolished binding of all MAbs of domains A and D, amino acid substitutions affected only MAbs belonging to the same domain as the MAb used to select the MAR mutant. However, a MAR mutation in a particular domain did not per se abolish binding of all MAbs recognizing that domain. Furthermore, MAR mutants possessed conservative as well as nonconservative amino acid substitutions. To investigate the significance of a secondary structure for the binding of MAbs, all cysteine residues in the N-terminal antigenic part of E1 were mutated to serine. We found that the cysteines at positions 693 and 737 were essential for binding by MAbs of domains B and C, whereas those at positions 792, 818, 828, and 856 appeared to be essential for the binding of most MAbs of domains A and D. These results fully comply with the previously proposed two-unit structure of the N-terminal half of E1. One unit consists of antigenic domains B and C, whereas the other unit consists of the highly conserved domain A and domain D. We conclude that the first six cysteines are critical for the correct folding of E1. A model of the antigenic structure of E1 is presented and discussed. Images PMID:7514680

van Rijn, P A; Miedema, G K; Wensvoort, G; van Gennip, H G; Moormann, R J

1994-01-01

340

Resolvin E1 reduces hepatic fibrosis in mice with Schistosoma japonicum infection.  

PubMed

The aim of this study was to investigate whether resolvin E1 (RvE1) protects against hepatic fibrosis in a murine model of liver fibrosis induced by Schistosoma japonicum infection. A total of 30 pathogen-free Kunming mice were randomly and equally divided into three groups: Control (uninfected, untreated), model (infected, untreated) and RvE1 intervention (infected, RvE1-treated; 100 ng daily). The mice were infected with Schistosoma japonicum by inoculating the abdominal skin with 20±2 cercariae to induce models of liver fibrosis. The area and numbers of the granulomas in the livers were assessed through histopathology after 70 days of treatment. The levels of tumor necrosis factor (TNF)-? and interferon (IFN)-? were evaluated in the serum by enzyme-linked immunosorbent assay (ELISA). The expression levels of TNF-? were detected in the hepatic tissue by reverse transcription-polymerase chain reaction and western blot analysis. The activity levels of alanine aminotransferase and aspartate aminotransferase were determined in the serum by ELISA. The expression levels of laminin (LN), hyaluronic acid (HA), procollagen type III (PC-III) and type IV collagen (IV-C) were detected in the serum by radioimmunoassays. The results revealed that the mean area of the granulomas was smaller in the RvE1 intervention group compared with that in the model group. Following RvE1 treatment, the serum levels of TNF-? were lower than those in the model group, while the serum levels of IFN-? were higher compared with those in the model group. The expression levels of TNF-? were lower in the hepatic tissue following RvE1 treatment compared with those in the model group. The indicators of liver fibrosis, the levels of LN, HA, PC-III and IV-C in the serum, were lower following RvE1 treatment than those in the model group. In conclusion, RvE1 treatment may reduce the growth of granulomas, thereby slowing the process of hepatic fibrosis, and this effect may be the result of anti-inflammatory and immune system adjustment. PMID:24926330

Qiu, Wenhong; Guo, Kaiwen; Yi, Luyang; Gong, Yeli; Huang, Lixia; Zhong, Wei

2014-06-01

341

Resolvin E1 reduces hepatic fibrosis in mice with Schistosoma japonicum infection  

PubMed Central

The aim of this study was to investigate whether resolvin E1 (RvE1) protects against hepatic fibrosis in a murine model of liver fibrosis induced by Schistosoma japonicum infection. A total of 30 pathogen-free Kunming mice were randomly and equally divided into three groups: Control (uninfected, untreated), model (infected, untreated) and RvE1 intervention (infected, RvE1-treated; 100 ng daily). The mice were infected with Schistosoma japonicum by inoculating the abdominal skin with 20±2 cercariae to induce models of liver fibrosis. The area and numbers of the granulomas in the livers were assessed through histopathology after 70 days of treatment. The levels of tumor necrosis factor (TNF)-? and interferon (IFN)-? were evaluated in the serum by enzyme-linked immunosorbent assay (ELISA). The expression levels of TNF-? were detected in the hepatic tissue by reverse transcription-polymerase chain reaction and western blot analysis. The activity levels of alanine aminotransferase and aspartate aminotransferase were determined in the serum by ELISA. The expression levels of laminin (LN), hyaluronic acid (HA), procollagen type III (PC-III) and type IV collagen (IV-C) were detected in the serum by radioimmunoassays. The results revealed that the mean area of the granulomas was smaller in the RvE1 intervention group compared with that in the model group. Following RvE1 treatment, the serum levels of TNF-? were lower than those in the model group, while the serum levels of IFN-? were higher compared with those in the model group. The expression levels of TNF-? were lower in the hepatic tissue following RvE1 treatment compared with those in the model group. The indicators of liver fibrosis, the levels of LN, HA, PC-III and IV-C in the serum, were lower following RvE1 treatment than those in the model group. In conclusion, RvE1 treatment may reduce the growth of granulomas, thereby slowing the process of hepatic fibrosis, and this effect may be the result of anti-inflammatory and immune system adjustment. PMID:24926330

QIU, WENHONG; GUO, KAIWEN; YI, LUYANG; GONG, YELI; HUANG, LIXIA; ZHONG, WEI

2014-01-01

342

Cross-Inhibition of Chikungunya Virus Fusion and Infection by Alphavirus E1 Domain III Proteins  

PubMed Central

Alphaviruses are small enveloped RNA viruses that include important emerging human pathogens, such as chikungunya virus (CHIKV). These viruses infect cells via a low-pH-triggered membrane fusion reaction, making this step a potential target for antiviral therapies. The E1 fusion protein inserts into the target membrane, trimerizes, and refolds to a hairpin-like conformation in which the combination of E1 domain III (DIII) and the stem region (DIII-stem) pack against a core trimer composed of E1 domains I and II (DI/II). Addition of exogenous DIII proteins from Semliki Forest virus (SFV) has been shown to inhibit E1 hairpin formation and SFV fusion and infection. Here we produced and characterized DIII and DI/II proteins from CHIKV and SFV. Unlike SFV DIII, both core trimer binding and fusion inhibition by CHIKV DIII required the stem region. CHIKV DIII-stem and SFV DIII-stem showed efficient cross-inhibition of SFV, Sindbis virus, and CHIKV infections. We developed a fluorescence anisotropy-based assay for the binding of SFV DIII-stem to the core trimer and used it to demonstrate the relatively high affinity of this interaction (Kd [dissociation constant], ?85 nM) and the importance of the stem region. Together, our results support the conserved nature of the key contacts of DIII-stem in the alphavirus E1 homotrimer and describe a sensitive and quantitative in vitro assay for this step in fusion protein refolding. PMID:23637415

Sánchez-San Martín, Claudia; Nanda, Soumya; Zheng, Yan; Fields, Whitney

2013-01-01

343

2-Carboxyquinoxalines Kill Mycobacterium tuberculosis through Noncovalent Inhibition of DprE1.  

PubMed

Phenotypic screening of a quinoxaline library against replicating Mycobacterium tuberculosis led to the identification of lead compound Ty38c (3-((4-methoxybenzyl)amino)-6-(trifluoromethyl)quinoxaline-2-carboxylic acid). With an MIC99 and MBC of 3.1 ?M, Ty38c is bactericidal and active against intracellular bacteria. To investigate its mechanism of action, we isolated mutants resistant to Ty38c and sequenced their genomes. Mutations were found in rv3405c, coding for the transcriptional repressor of the divergently expressed rv3406 gene. Biochemical studies clearly showed that Rv3406 decarboxylates Ty38c into its inactive keto metabolite. The actual target was then identified by isolating Ty38c-resistant mutants of an M. tuberculosis strain lacking rv3406. Here, mutations were found in dprE1, encoding the decaprenylphosphoryl-d-ribose oxidase DprE1, essential for biogenesis of the mycobacterial cell wall. Genetics, biochemical validation, and X-ray crystallography revealed Ty38c to be a noncovalent, noncompetitive DprE1 inhibitor. Structure-activity relationship studies generated a family of DprE1 inhibitors with a range of IC50's and bactericidal activity. Co-crystal structures of DprE1 in complex with eight different quinoxaline analogs provided a high-resolution interaction map of the active site of this extremely vulnerable target in M. tuberculosis. PMID:25427196

Neres, João; Hartkoorn, Ruben C; Chiarelli, Laurent R; Gadupudi, Ramakrishna; Pasca, Maria Rosalia; Mori, Giorgia; Venturelli, Alberto; Savina, Svetlana; Makarov, Vadim; Kolly, Gaelle S; Molteni, Elisabetta; Binda, Claudia; Dhar, Neeraj; Ferrari, Stefania; Brodin, Priscille; Delorme, Vincent; Landry, Valérie; de Jesus Lopes Ribeiro, Ana Luisa; Farina, Davide; Saxena, Puneet; Pojer, Florence; Carta, Antonio; Luciani, Rosaria; Porta, Alessio; Zanoni, Giuseppe; De Rossi, Edda; Costi, Maria Paola; Riccardi, Giovanna; Cole, Stewart T

2014-12-01

344

Polymorphisms of E1 and GIGANTEA in wild populations of Lotus japonicus.  

PubMed

In plants, timing of flowering is an essential factor that controls the survival rates of descendants. The circadian clock genes E1 and GIGANTEA (GI) play a central role in transmitting signals to flowering locus T (FT) in leguminous plants. Lotus japonicus is a wild Japanese species that ranges from northern Hokkaido to the southern Ryukyus and exhibits a wide range in terms of the time between seeding and first flowering. In this study, we first identified LjGI and analyzed polymorphisms of LjE1 and LjGI among wild populations covering the entire distribution range of this species in Japan. LjGI had a coding sequence (CDS) length of 3495 bp and included 14 exons. The homologies of DNA and amino acid sequences between LjGI and GmGI were 89 and 88% (positive rate was 92%), respectively. LjE1 harbored five nucleic acid changes in a 552 bp CDS, all of which were nonsynonymous; four of the changes were located in the core function area. LjE1 alleles exhibited partial north-south differentiation and non-neutrality. In contrast, the LjGI harbored one synonymous and one nonsynonymous change. Thus, our study suggests that LjE1 may be involved in the control of flowering times, whereas LjGI may be under strong purifying selection. PMID:25117507

Wakabayashi, Tomomi; Oh, Hana; Kawaguchi, Masayoshi; Harada, Kyuya; Sato, Shusei; Ikeda, Hajime; Hiroaki, Setoguchi

2014-11-01

345

Activation of the human beta interferon gene by the adenovirus type 12 E1B gene  

SciTech Connect

The transcription of endogenous beta interferon mRNA was activated in human embryo kidney (HEK) cells infected with adenovirus 12 (Ad12) but was activated only inefficiently or not at all in HEK cells infected with Ad5 and rc-1 (Ad5 dl312 containing the Ad12 E1A region). The analysis with Ad12 mutants showed that Ad12 E1B products, especially the 19K protein, were important for the expression of the endogenous beta interferon gene and Ad12 E1A products were not involved in the expression. The expression of exogeneously transfected pIFN-CAT (a hybrid plasmid having the human beta interferon promoter fused with the CAT gene) was activated in HEK and chicken embryo fibroblast (CEF) cells infected with either Ad12 or Ad5. The analysis of cotransfection of CEF cells with pIFN-CAT and plasmids containing fragments of Ad12 or Ad5 DNA showed that Ad12 or Ad5 E1B (possibly the 19K protein) was and E1A was not involved in the expression of the exogenous pIFN-CAT.

Shiroki, K.; Toth, M.

1988-01-01

346

Expression and Characterization of Acidothermus celluloyticus E1 Endoglucanase in Transgenic Duckweed Lemna minor 8627  

SciTech Connect

Endoglucanase E1 from Acidothermus cellulolyticus was expressed cytosolically under control of the cauliflower mosaic virus 35S promoter in transgenic duckweed, Lemna minor 8627 without any obvious observable phenotypic effects on morphology or rate of growth. The recombinant enzyme co-migrated with the purified catalytic domain fraction of the native E1 protein on western blot analysis, revealing that the cellulose-binding domain was cleaved near or in the linker region. The duckweed-expressed enzyme was biologically active and the expression level was up to 0.24% of total soluble protein. The endoglucanase activity with carboxymethylcellulose averaged 0.2 units mg protein{sup -1} extracted from fresh duckweed. The optimal temperature and pH for E1 enzyme activity were about 80 C and pH 5, respectively. While extraction with HEPES (N-[2-hydroxyethyl]piperazine-N{prime}-[2-ethanesulfonic acid]) buffer (pH 8) resulted in the highest recovery of total soluble proteins and E1 enzyme, extraction with citrate buffer (pH 4.8) at 65 C enriched relative amounts of E1 enzyme in the extract. This study demonstrates that duckweed may offer new options for the expression of cellulolytic enzymes in transgenic plants.

Sun, Y.; Cheng, J. J.; Himmel, M. E.; Skory, C. D.; Adney, W. S.; Thomas, S. R.; Tisserat, B.; Nishimura, Y.; Yamamoto, Y. T.

2007-01-01

347

Identification of a novel human papillomavirus type 16 E1 gene variant with potentially reduced oncogenicity.  

PubMed

The human papillomavirus (HPV) 16 genome has been studied extensively, although no study has focused on the E1 gene that is implicated in viral DNA replication. After analyzing the E1 region of HPV 16 genomes in 429 cervical samples, 11.2% were found to contain a 63 nucleotides duplication in this region. Sequence analysis of the E6 and the E7 regions has shown that all samples containing this duplication were related to E6-G350 variant of the HPV 16 (Chi square test, P = 0.0012). A comparison of cervical lesion severity of the examinees having regular or variant E1 genes has shown that the variant group had a significantly (Fischer's exact test, P = 0.0401) lower percentage of high grade disease cases, suggesting that this particular duplication might reduce the oncogenic potential of HPV 16, and also might clarify the differences of E6-G350 variant oncogenicity observed in European populations. Albeit, a decreased incidence of high grade cervical lesions can be linked to the prevalence of multiple HPV infection, the additional decrease of those cases with the variant E1 gene versus those without (10.5% and 18.6%, respectively) can only be ascribed to the effect of this particular HPV variant. Further research is needed to clarify the biology of these HPV 16 E1 variants. PMID:19040290

Sabol, Ivan; Matovina, Mihaela; Gasperov, Nina Milutin; Grce, Magdalena

2008-12-01

348

Estimation of the value and localization of possible systematic errors in determination of level density and radiative strength functions from the (n,2gamma) -reaction  

E-print Network

Systematic error in determination of the absolute intensities of the two-step gamma-cascades after the thermal neutron capture and its influence on the value and localization of extracted from (n,2gamma)-reaction probable level densities and radiative strength functions of dipole gamma-transitions have been analysed. It was found that this error in limits of its possible magnitude cannot change made earlier conclusions about the radiative strength functions of E1- and M1- transitions at Egamma ~ 3 MeV and level density of heavy nucleus below ~0.5Bn.

V. A. Khitrov; Li Chol; A. M. Sukhovoj

2004-04-23

349

INFLUENCE OF STRENGTH AND FLEXIBILITY TRAINING, COMBINED OR ISOLATED, ON STRENGTH AND FLEXIBILITY GAINS.  

PubMed

The aim of this study was to analyze the strength and flexibility gains after 12 weeks of strength and flexibility training, isolated or combined. Twenty-eight trained women (mean ± SD age = 46 ± 6.52 years; body mass = 56.8 ± 5.02 kg; height = 162 ± 5.58 cm) were randomly divided into four groups: strength training (ST) (n = 7), flexibility training (FLEX) (n = 7), combination of strength and flexibility (ST + FLEX) (n = 7), and combination of flexibility and strength (FLEX + ST) (n = 7). All groups were assessed pre- and post-training for the Sit-and-Reach test, goniometry, and ten repetition maximum (10RM) in bench press and leg press exercises. The training protocol for all groups included training sessions on alternate days, and was composed of eight exercises performed at periodized intensities. The flexibility training consisted of dynamic stretching performed for a total duration of 60 minutes. The results demonstrated significant strength gains in all groups in the leg press exercise (FLEX p = 0.0187; ST p = 0.0001; FLEX + ST p = 0.0034; ST + FLEX p = 0.0021). All groups except the FLEX improved in bench press strength (FLEX p = 0.1757; ST p = 0.0001; FLEX + ST p = 0.0017; ST + FLEX p = 0.0035). Statistical analyses did not show significant differences between groups; however, effect sizes demonstrated slightly different treatment effects for each group. Largest treatment effects were calculated for the ST group (Leg press: 2.72; bench press: 1.25) and the lowest effects in the FLEX group (leg press: .41; bench press: -.06). Both combination groups demonstrated lower effect sizes for both leg press and bench press as compared to the ST group. No significant differences in flexibility were seen in any group, in any of the comparisons (p > 0.05). In conclusion, these findings suggest that combining strength and flexibility training is not detrimental to flexibility development; however, combined training may slightly reduce strength development, with little influence of order in which these exercises are performed. PMID:25268286

Leite, Thalita; de Souza Teixeira, Arlindo; Saavedra, Francisco; Leite, Richard Diego; Rhea, Matthew R; Simão, Roberto

2014-09-29

350

Heterogeneous deformation and mechanical strength of materials - Approach to the theoretical strength  

NASA Astrophysics Data System (ADS)

Grain size in polycrystalline materials was changed from larger than phi 10 mum to smaller than phi 10 nm, and the effects of both grain size and strain rate on the strength has been investigated from a view point of heterogeneous deformation. Grains of phi10 nm or less in size were obtained by crystallization of amorphous alloys. The experimental results are summarized as follows: (a) Heterogeneous deformation is effectively suppressed when grain size decreases smaller than about phi0.1 mum. As a result, the strength remarkably increases in this grain size range, and takes the maximum value when grains of phi10 nm in size are homogeneously formed, (b) When grain size becomes smaller than phi10 nm, those ultrafine grains are embedded into the amorphous matrix, and the strength decreases with increasing volume fraction of amorphous phase. (c) Heterogeneous deformation is also effectively suppressed by increasing strain rate in general as well as decreasing grain size. The maximum strength obtained experimentally is compared with the theoretical strengths estimated under various conditions.

Fujita, H.; Fujita, N.

2002-01-01

351

Design Project Design for an Elementary Strength  

NSDL National Science Digital Library

Our goal is to enable deeper learning by undergraduate engineering students via experience with an open-ended design project. In addition to knowledge, comprehension, and application, engineering design requires students to analyze and synthesize. Furthermore, students must practice divergent thinking to explore the entire design space, which is an immensely important skill for developing creative and effective solutions. Learning design via a team-based design project promotes cognitive skills, social skills, management skills, and positive personal traits. Design and development of an open ended design project is discussed. The team-based project progresses over approximately ten weeks in an elementary strength of materials course. This provides a significant design experience for engineering students that helps bridge the gap between the first-year engineering design course and the capstone design project that engineering students typically do in their senior year. The project requires student teams to: work together, apply standards, create a conceptual design, select appropriate materials, identify applied loading scenarios, perform the design analysis, check design calculations from another team, create design drawings, estimate the cost, and write a design report. In order to accomplish all this in a course like strength of materials, which is laden with analysis, the project must be well organized and accompanied with web-based tools. This paper discusses design of the design project, course content that is beyond the traditional strength of materials course coverage, and development of web-based tools that make this possible. The web-based tools provide guidance on: the design process with interactive examples, analysis and simulation, materials properties and selection, administering team projects (for instructors), working team projects (for students), as well as environmental, economical, social, and ethical issues.

Lissenden, Cliff; Miller, Andrew; Salamon, Nicholas

2011-06-09

352

Regulation of the effects of CYP2E1-induced oxidative stress by JNK signaling  

PubMed Central

The generation of excessive amounts of reactive oxygen species (ROS) leads to cellular oxidative stress that underlies a variety of forms of hepatocyte injury and death including that from alcohol. Although ROS can induce cell damage through direct effects on cellular macromolecules, the injurious effects of ROS are mediated largely through changes in signal transduction pathways such as the mitogen-activated protein kinase c-Jun N-terminal kinase (JNK). In response to alcohol, hepatocytes have increased levels of the enzyme cytochrome P450 2E1 (CYP2E1) which generates an oxidant stress that promotes the development of alcoholic steatosis and liver injury. These effects are mediated in large part through overactivation of JNK that alters cell death pathways. Targeting the JNK pathway or its downstream effectors may be a useful therapeutic approach to the oxidative stress generated by CYP2E1 in alcoholic liver disease. PMID:25462060

Schattenberg, Jörn M.; Czaja, Mark J.

2014-01-01

353

E1A-induced immortalization of rat type II alveolar epithelial cells.  

PubMed

Using a retroviral vector expressing the adenoviral 12S E1A gene product the authors have immortalized rat type II alveolar epithelial cells. For a period of time, the immortalized cells retain many of the ultrastructural characteristics of type II cells in situ, including the presence of lamellar bodies. By 250 days in culture, however, neither lamellar bodies, SP-A, nor a phospholipid profile characteristic of surfactant were present. The cell bind the lectin Maclura pomifera and stably express cytokeratins and the E1A gene product. The cell line also has a diploid karyotype, exhibits contact inhibition of growth, and does not grow in soft agar. E1A-immortalized cell lines should prove useful as models for study of certain aspects of type II alveolar epithelial cell function. PMID:8886757

Pasternack, M; Floerchinger, C S; Hunninghake, G W

1996-01-01

354

Isoscalar giant resonance strength in (24)Mg  

E-print Network

PHYSICAL REVIEW C 80, 064318 (2009) Isoscalar giant resonance strength in 24Mg D. H. Youngblood, Y.-W. Lui, X. F. Chen,* and H. L. Clark Cyclotron Institute, Texas A&M University, College Station, Texas 77843, USA (Received 13 November 2009... for the individual 0556-2813/2009/80(6)/064318(5) 064318-1 ?2009 The American Physical Society YOUNGBLOOD, LUI, CHEN, AND CLARK PHYSICAL REVIEW C 80, 064318 (2009) 24Mg(?,?') E?=240 MeV 0 10 20 30 40 0 20 40 60 0 20 40 60 0 20 40 60 Ex(MeV) d2...

Youngblood, David H.; Lui, Y. -W; Chen, X. F.; Clark, H. L.

2009-01-01

355

Electromagnetic Dipole Strength in Transitional Nuclei  

E-print Network

Electromagnetic dipole absorption cross-sections of transitional nuclei with large-amplitude shape fluctuations are calculated in a microscopic way by introducing the concept of Instantaneous Shape Sampling. The concept bases on the slow shape dynamics as compared to the fast dipole vibrations. The elctromagnetic dipole strength is calculated by means of RPA for the instantaneous shapes, the probability of which is obtained by means of IBA. Very good agreement with the experimental absorption cross sections near the nucleon emission threshold is obtained.

S. Q. Zhang; I. Bentley; S. Brant; F. Dönau; S. Frauendorf; B. Kämpfer; R. Schwengner; A. Wagner

2008-08-19

356

Hydrodynamic compressibility of high-strength ceramics  

SciTech Connect

In this study we have developed the techniques to investigate the hydrodynamic response of high-strength ceramics by mixing these powders with copper powder, preparing compacts, and performing shock compression tests on these mixtures. Hydrodynamics properties of silicon carbide, titanium diboride, and boron carbide to 30 GPa were examined by this method, and hydrodynamic compression data for these ceramics have been determined. We have concluded, however, that the measurement method is sensitive to sample preparation and uncertainties in shock wave measurements. Application of the experimental technique is difficult and further efforts are needed.

Grady, D.E.

1993-08-01

357

Boron aluminum crippling strength shows improvement  

NASA Technical Reports Server (NTRS)

Results are presented from an experimental program directed toward improving boron aluminum crippling strength. Laminate changes evaluated were larger filament diameter, improved processing, shape changes, adding steel-aluminum cross plies, reduced filament volume in corners, adding boron aluminum angle plies, and using titanium interleaves. Filament diameter and steel-aluminum cross plies have little effect on crippling. It is shown that better processing combined with appropriate shape changes improved crippling over 50 percent at both room temperature and 600 F. Tests also show that crippling improvements ranging from 20 to 40 percent are achieved using angle plies and titanium interleaves.

Otto, O. R.; Bohlmann, R. E.

1974-01-01

358

Protective claddings for high strength chromium alloys  

NASA Technical Reports Server (NTRS)

The application of a Cr-Y-Hf-Th alloy as a protective cladding for a high strength chromium alloy was investigated for its effectiveness in inhibiting nitrogen embrittlement of a core alloy. Cladding was accomplished by a combination of hot gas pressure bonding and roll cladding techniques. Based on bend DBTT, the cladding alloy was effective in inhibiting nitrogen embrittlement of the chromium core alloy for up to 720 ks (200hours) in air at 1422 K (2100 F). A significant increase in the bend DBTT occurred with longer time exposures at 1422 K or short time exposures at 1589 K (2400 F).

Collins, J. F.

1971-01-01

359

SIZE DEPENDENCE OF FLEXURAL STRENGTH AND FATIGUE STRENGTH OF PAVEMENT CONCRETE  

NASA Astrophysics Data System (ADS)

The size effect on flexural fatigue strength of concrete was experime ntally investigated. For this purpose, specimens of two sizes were prepared: 150mm x 150mm x 530mm (span=450mm) and 200mm x 450mm x 1800mm (span=1350mm). The stress levels were set at 70%, 80% and 90% of the compressive strength. Experimental results showed that the number of loading cycles at failure increased with the enlargement of specimens. Based on a fracture mechanics approach, with a stress level of 70%, this dependence of flexural fatigue strength on size was explained by the difference in the stress distributions in the sections of small and large sized specimens. A te nsion softening stress region was formed in the section of the small specimen, whereas elastic stress was produced over the full section in the large specimen.

Yoshimoto, Toru; Sato, Ryoichi

360

Effect of recycled coarse aggregate on concrete compressive strength  

Microsoft Academic Search

The effect of recycled coarse aggregate on concrete compressive strength was investigated based on the concrete skeleton theory.\\u000a For this purpose, 30 mix proportions of concrete with target cube compressive strength ranging from 20 to 60 MPa were cast\\u000a with normal coarse aggregate and recycled coarse aggregate from different strength parent concretes. Results of 28-d test\\u000a show that the strength

Zhenshuang Wang; Lijiu Wang; Zhenglong Cui; Mei Zhou

2011-01-01

361

Climate strength: a new direction for climate research  

Microsoft Academic Search

Climate strength was conceptualized within D. Chan's (1998) discussion of compositional models and the concept of culture strength from the organizational culture literature. Climate strength was opera- tionalized in terms of within-group variability in climate perceptions—the less within-group variability, the stronger the climate. The authors studied climate strength in the context of research linking employee service climate perceptions to customer

Benjamin Schneider; Amy Nicole Salvaggio; Montse Subirats

2002-01-01

362

Strength of magnesia-core crown with different body porcelains.  

PubMed

The diametral strengths of magnesia-core crowns made with different body porcelains, Will-Ceram, Crystar, Ceramco II, and Vita VMK 68, were measured. The results were compared to the diametral strengths of aluminous-core crowns and Renaissance crowns. A one-way analysis of variance showed that there were no significant differences in the strengths of magnesia-core crowns or the aluminous-core crowns, but the Renaissance crown strengths were significantly lower. PMID:8507332

Liu, C C; O'Brien, W J

1993-01-01

363

Strength and conditioning practices of United States high school strength and conditioning coaches.  

PubMed

This study describes the results of a survey of the practices of high school strength and conditioning (HS S&C) coaches. Thirty-eight of 128 (29.7%) HS S&C coaches, who were surveyed, responded. This survey examines background information, physical testing, flexibility development, speed development, agility development, plyometrics, strength/power development and program design, nutrition, and injury frequency. High school strength and conditioning coaches average 14.78 years in the profession, and 89% of the survey respondents were certified by the National Strength and Conditioning Association. Coaches assess an average of 5.83 different parameters of fitness, with strength as well as power being the most common parameters assessed. Coaches tested an average of 3.86 times a year with an average of 8.51 specific tests per testing session. All HS S&C coaches used a variety of flexibility development strategies using dynamic stretching more frequently than static. Thirty-six of 38 (95%) coaches follow a periodization model, 37 of 38 (97.4%) coaches indicated that their athletes used Olympic-style lifts, and 37 of 37 (100%) coaches responding to this question used plyometric training with their athletes. The squat and its variations, as well as the Olympic-style lifts and its variations, were most frequently identified as the most important exercises prescribed. All coaches use speed development and agility training strategies with their athletes. This survey examined a variety of other practices and provides detailed information about these practices at the high school level. Coaches are encouraged to review the strength and conditioning practices described in this survey and identify and implement the ideas that may improve their practices. PMID:19826308

Duehring, Michael D; Feldmann, Christina R; Ebben, William P

2009-11-01

364

Attitude Strength: An Extra-Content Aspect of Attitude.  

ERIC Educational Resources Information Center

Attitude strength is considered as an extra-content aspect of attitude. A model of the relationship of attitude strength to attitude direction and behavior proposes that attitude strength is comprised of three dimensions that moderate the relationship between attitude direction and behavior. The dimensions are parallel to the tripartite dimensions…

Alwitt, Linda F.

365

Size effect on compressive strength of reactive powder concrete  

Microsoft Academic Search

In this paper the coefficient and law of the size effect of RPC were studied through experiments and theoretical analysis. The size-effect coefficients for the compressive strength of RPC are deduced through experiments. They indicate that RPC without fiber behaves quite the same as normal or high strength concrete. The size effect on compressive strength is more prominent in RPC

Ming-zhe AN; Li-jun ZHANG; Quan-xin YI

2008-01-01

366

Quantitative assessment and training of isometric cervical extension strength  

Microsoft Academic Search

The purpose of this study was to evaluate the reliability and variability of repeated measurements of isometric cervical extension strength and determine the effect of 10 weeks of dynamic variable resistance cervical ex tension training on isometric cervical extension strength. Seventy-three subjects (age, 29 ± 12 years [mean ± SD]) completed isometric cervical extension strength tests on 4 separate days

Scott H. Leggett; James E. Graves; Michael L. Pollock; Michael Shank; David M. Carpenter; Bryon Holmes; Michael Fulton

1991-01-01

367

Strengths-Based Education: Probing Its Limits. The Cutting Edge  

ERIC Educational Resources Information Center

Except for Timothy Hodges and James Harter's restrained research summary, the feature articles in this issue are evangelical in their praise of strengths-based education. It is, they assure us, a major innovation. English teacher Alexis Onishi writes that StrengthsQuest, a specific strengths-based approach, will have "a lifelong impact on how…

Clabaugh, Gary K.

2005-01-01

368

Cohesive Strength of Gas-hydrate-bearing Marine Sediments  

Microsoft Academic Search

We examine the relationship between gas hydrate saturation and the cohesive strength of marine sediments in a variety of continental margin settings. The cohesive strength (cohesion) is a fundamental physical property controlling sediment resistance to compressive failure. The cohesion (Co), is typically defined by the uncompressive rock strength and the friction angle, but it can also be related to the

A. E. Cook; D. Goldberg

2005-01-01

369

Testing the Shear Strength of Gummy Bear Mountain  

NSDL National Science Digital Library

Students do background reading from the text on physical weathering and the components of shear strength. Students write hypotheses about the shear strength of different sizes and shapes of gummy candy. The students then uses simple experiments to demonstrate and test the shear strength of the candy types.

Keen-Zebert, Amanda

370

Autism Severity and Muscle Strength: A Correlation Analysis  

ERIC Educational Resources Information Center

The current study examined the relationship between muscle strength, as measured by hand grip strength, and autism severity, as measured by the Childhood Autism Rating Scale (CARS). Thirty-seven (37) children with a diagnosis of autism spectrum disorder (ASD) were evaluated using the CARS and then tested for hand muscle strength using a hand grip…

Kern, Janet K.; Geier, David A.; Adams, James B.; Troutman, Melissa R.; Davis, Georgia; King, Paul G.; Young, John L.; Geier, Mark R.

2011-01-01

371

Measures of Strength and Fitness for Older Populations.  

ERIC Educational Resources Information Center

The overall strength of the musculature does not require testing of large numbers of muscle groups and can be accomplished from three or four tests. Small batteries of strength tests have been devised to predict total strength. The best combination of tests for males are thigh flexors, leg extensors, arm flexors, and pectoralis major. The battery…

Osness, Wayne H.; Hiebert, Lujean M.

372

Bond Strength of Polymer Lightweight Aggregate Tayfun Uygunoglu,1  

E-print Network

Bond Strength of Polymer Lightweight Aggregate Concrete Tayfun Uygunoglu,1 Witold Brostow,2 Osman lightweight concrete (PLC), pull-out test for bond strength and compressive strength tests were performed properties of lightweight PC were investigated with inclusion of pumice lightweight aggregate in maximum size

North Texas, University of

373

Some characteristics of high strength fiber reinforced lightweight aggregate concrete  

Microsoft Academic Search

The effect of polypropylene and steel fibers on high strength lightweight aggregate concrete is investigated. Sintered fly ash aggregates were used in the lightweight concrete; the fines were partially replaced by fly ash. The effects on compressive strength, indirect tensile strength, modulus of rupture, modulus of elasticity, stress–strain relationship and compression toughness are reported. Compared to plain sintered fly ash

O Kayali; M. N Haque; B Zhu

2003-01-01

374

Strength of Si Wafers with Microcracks: A Theoretical Model (Poster)  

SciTech Connect

A new analytical expression that takes into account the surface, edge, and bulk properties of a wafer has been proposed to describe the strength of the brittle materials. A new proposed fracture-mechanics numerical simulation successfully predicted the strength of the cast silicon wafers. It has been shown that the predicted wafer strength distribution agrees well with the available experimental results.

Rupnowski, P.; Sopori, B.

2008-05-01

375

Low-energy behavior of E 2 strength functions  

NASA Astrophysics Data System (ADS)

Electric quadrupole strength functions have been deduced from averages of a large number of E 2 transition strengths calculated within the shell model for the nuclides 94Mo and 95Mo. These strength functions are at variance with phenomenological approximations as provided by the Reference Input Parameter Library RIPL-3 for calculations of reaction rates on the basis of the statistical model.

Schwengner, R.

2014-12-01

376

HELIOSPHERIC MODULATION STRENGTH DURING THE NEUTRON MONITOR ERA  

E-print Network

HELIOSPHERIC MODULATION STRENGTH DURING THE NEUTRON MONITOR ERA I. G. USOSKIN1, K. ALANKO2, K modulation strength . Convoluting these spectra with the specific yield function of a neutron monitor, we this relation, we calculate the modulation strength using the actually recorded neutron monitor count rates. We

Usoskin, Ilya G.

377

NDT measurements for the prediction of 28-day compressive strength  

Microsoft Academic Search

A procedure is proposed for the prediction of the compressive strength of concrete based on the use of NDT measurements. Prior to formwork removal, electrical resistivity can be assessed and based on an electrical resistivity versus compressive strength correlation curve, the strength of concrete can be estimated. This procedure ensures, for example, that the formwork is only removed when the

Rui Miguel Ferreira; Said Jalali

2010-01-01

378

Drained Shear Strength Parameters for Analysis of Landslides  

E-print Network

Drained Shear Strength Parameters for Analysis of Landslides Timothy D. stark'; Hangseok choi2;and of drained shear strength parameters for analysis of landslides. In particular, the importance, existence for landslide analyses, empirical relationships for the drained residual and fully softened strengths

379

FURTHER PREDICTIONS ABOUT WELD METAL STRENGTH 6.1 INTRODUCTION  

E-print Network

CHAPTER 6 FURTHER PREDICTIONS ABOUT WELD METAL STRENGTH 6.1 INTRODUCTION In general, when the yield strength of a weld as the sum of the products of the volume fractions of the three principal be taken into account. In Chapter 5, it was shown that the strength of a weld can be factorised

Cambridge, University of

380

Magnetic Element Meridional Flow: Dependence on Strength  

NASA Astrophysics Data System (ADS)

Meridional Flow (MF) speeds are only on the order of 10-20 m/s. For this reason, MF is the most difficult transport velocity to measure. However, these velocities can be measured by tracking the motion of small magnetic elements on the surface of the sun and averaging over a Carrington Rotation (CR). Magnetograms obtained by the HMI instrument aboard SDO are turned into maps of the magnetic features. Strips from these maps, taken 8 hours apart, are then cross-correlated to determine the distances in latitude and longitude that flux elements have moved, thus producing MF and differential rotation velocities as functions of latitude. Averaging the MFs obtained for every 8 hour separation over a 27-day CR produces a MF profile for that CR. This process was repeated for data with varying magnetic element strength. Results show that the MF is more complex than previously thought. It varies with the strength of the magnetic elements. The MF is slower for the stronger flux elements. This is consistent with stronger flux elements being anchored deeper in the Sun's surface shear layer where the MF is slower. New Surface Flux Transport and Solar Dynamo models should reproduce solar conditions while including these variations.

Rightmire, Lisa; Hathaway, D.

2011-05-01

381

Magnetic field strength of active region filaments  

NASA Astrophysics Data System (ADS)

Aims: We study the vector magnetic field of a filament observed over a compact active region neutral line. Methods: Spectropolarimetric data acquired with TIP-II (VTT, Tenerife, Spain) of the 10 830 Å spectral region provide full Stokes vectors that were analyzed using three different methods: magnetograph analysis, Milne-Eddington inversions, and PCA-based atomic polarization inversions. Results: The inferred magnetic field strengths in the filament are around 600-700 G by all these three methods. Longitudinal fields are found in the range of 100-200 G whereas the transverse components become dominant, with fields as high as 500-600 G. We find strong transverse fields near the neutral line also at photospheric levels. Conclusions: Our analysis indicates that strong (higher than 500 G, but below kG) transverse magnetic fields are present in active region filaments. This corresponds to the highest field strengths reliably measured in these structures. The profiles of the helium 10 830 Å lines observed in this active region filament are dominated by the Zeeman effect.

Kuckein, C.; Centeno, R.; Martínez Pillet, V.; Casini, R.; Manso Sainz, R.; Shimizu, T.

2009-07-01

382

Abstract spatial reasoning as an autistic strength.  

PubMed

Autistic individuals typically excel on spatial tests that measure abstract reasoning, such as the Block Design subtest on intelligence test batteries and the Raven's Progressive Matrices nonverbal test of intelligence. Such well-replicated findings suggest that abstract spatial processing is a relative and perhaps absolute strength of autistic individuals. However, previous studies have not systematically varied reasoning level--concrete vs. abstract--and test domain--spatial vs. numerical vs. verbal, which the current study did. Autistic participants (N?=?72) and non-autistic participants (N?=?72) completed a battery of 12 tests that varied by reasoning level (concrete vs. abstract) and domain (spatial vs. numerical vs. verbal). Autistic participants outperformed non-autistic participants on abstract spatial tests. Non-autistic participants did not outperform autistic participants on any of the three domains (spatial, numerical, and verbal) or at either of the two reasoning levels (concrete and abstract), suggesting similarity in abilities between autistic and non-autistic individuals, with abstract spatial reasoning as an autistic strength. PMID:23533615

Stevenson, Jennifer L; Gernsbacher, Morton Ann

2013-01-01

383

Abstract Spatial Reasoning as an Autistic Strength  

PubMed Central

Autistic individuals typically excel on spatial tests that measure abstract reasoning, such as the Block Design subtest on intelligence test batteries and the Raven’s Progressive Matrices nonverbal test of intelligence. Such well-replicated findings suggest that abstract spatial processing is a relative and perhaps absolute strength of autistic individuals. However, previous studies have not systematically varied reasoning level – concrete vs. abstract – and test domain – spatial vs. numerical vs. verbal, which the current study did. Autistic participants (N?=?72) and non-autistic participants (N?=?72) completed a battery of 12 tests that varied by reasoning level (concrete vs. abstract) and domain (spatial vs. numerical vs. verbal). Autistic participants outperformed non-autistic participants on abstract spatial tests. Non-autistic participants did not outperform autistic participants on any of the three domains (spatial, numerical, and verbal) or at either of the two reasoning levels (concrete and abstract), suggesting similarity in abilities between autistic and non-autistic individuals, with abstract spatial reasoning as an autistic strength. PMID:23533615

Stevenson, Jennifer L.; Gernsbacher, Morton Ann

2013-01-01

384

Determinants of eggshell strength in endangered raptors.  

PubMed

We compared eggshell strength in a group of falcon taxa including the peregrine falcon (Falco peregrinus peregrinus), the red shaheen falcon (F. peregrinus babylonicus), the saker falcon (F. cherrug), the gyr falcon (F. rusticolus) and some interspecific and intraspecific hybrids. Our results showed that smaller falcons (<1,000 g) of the peregrine group have eggshells that are significantly softer (x=13.3 N) and thinner (x=0.26 mm) (n=107 eggs) than larger falcons (>1,000 g) of the gyr-saker group (x=20.8 N and 0.39 mm, respectively, n=81 eggs). We found a significant positive correlation between egg hardness and eggshell thickness. Linear mixed models showed that clutches from heavier females consisted of larger and harder eggs with thicker shells and thicker egg membranes. Eggs produced by older females and eggs laid later in the laying sequence were relatively smaller and softer and had relatively thin egg membranes and eggshells. Individual females, irrespective of their age, contributed significantly to the observed variation in egg strength. Egg size and hardness of hybrid eggs were similar to that of the pure species suggesting that hybridization does not affect eggshell hardness or thickness. Our study provides quantitative evidence of several factors, other than levels of contamination, which may affect eggshell thickness and hardness in falcons. PMID:19267399

Castilla, Aurora M; Herrel, Anthony; Van Dongen, Stefan; Furio, Naoki; Negro, Juan José

2009-04-01

385

Contribution of CYP2E1 to N-methyl-2-pyrrolidone metabolism.  

PubMed

The involvement of cytochrome P450 2E1 (CYP2E1) in the metabolism of N-methyl-2-pyrrolidone (NMP) was studied with three experimental approaches: in the rat, in vitro in human microsomes, and in human volunteers. NMP was administered dermally (40 mg/kg) to OFA rats to examine the influence of CYP2E1 inhibition (5 mg/kg diethyldithiocarbamate, DETC, 30 min before) and CYP2E1 induction (after 4 days of fasting). The main NMP metabolite 5-hydroxy- N-methylpyrrolidone (5HNMP) in the urine fractions collected during the following 48 h was analysed by gas chromatography-mass spectrometry. CYP2E1 inhibition led to a statistically significant retardation of 5HNMP excretion in urinary fractions collected during the first 12 h. In the group of fasted rats, a two-fold increase of CYP2E1 activity was observed in comparison with the control group. During the first 6 h after dermal administration of NMP to fasted rats, about 33% of the dose was excreted in urine versus 22% in controls. In vitro, NMP (15 mM) was incubated (up to120 min) with human liver microsomes and the formation of 5HNMP followed Michaelis-Menten kinetics with V(max) of 1.1 nmol/min per mg protein and K(m) of 2.4 mM. The formation of 5HNMP was inhibited by 35% in the presence of a monoclonal antibody against CYP2E1, but not by CYP1A2 antibody. In a dermal application experiment, 12 humans volunteers were exposed by means of a dermal patch to 300 mg NMP; five urine fractions were collected during the 48 h following the onset of application in order to measure the major metabolites 5HNMP and 2-hydroxymethylsuccinimide (2HMSI). Before NMP application, a blood sample was collected for the quantification of CYP2E1 mRNA in peripheral blood lymphocytes (PBLs). The mean dermal absorption of NMP was 67.9%. The highest amount of 5HNMP was excreted in urine in the fraction collected between 6-12 h (12.6% of dose), while 2HMSI peaked in fractions 12-24 h and 36-48 h (3.3 and 3.2% of dose, respectively). A significant relationship was found between CYP2E1 mRNA content in PBLs and the amount of both the metabolites excreted in urine within 24 h ( r(2)=0.54, P<0.01). It is concluded that CYP2E1 is involved in the first steps of NMP metabolism in the rat and, to a lesser extent, in humans. Since large variations in CYP2E1 activity exist in the human population (at least 5-fold range), it seems justified to take into account the activity of this enzyme in an individual for an accurate interpretation of biological monitoring of exposure to NMP when relying on 5HNMP and/or 2HMSI determination in urine. PMID:12734639

Ligocka, Danuta; Lison, Dominique; Haufroid, Vincent

2003-05-01

386

Effects of binder strength and aggregate size on the compressive strength and void ratio of porous concrete  

Microsoft Academic Search

To test the influence of binder strength, porous concretes with 4 binder strengths between 30.0–135.0 MPa and 5 void ratios between 15%–35% were tested. The results indicated that for the same aggregate, the rates of strength reduction due to the increases in void ratio were the same for binders with different strengths. To study the influence of aggregate size, 3

P. Chindaprasirt; S. Hatanaka; N. Mishima; Y. Yuasa; T. Chareerat

2009-01-01

387

In vitro biomimetic construction of hydroxyapatite-porcine acellular dermal matrix composite scaffold for MC3T3-E1 preosteoblast culture.  

PubMed

The application of porous hydroxyapatite-collagen (HAp-Collagen) as a bone tissue engineering scaffold is hindered by two main problems: its high cost and low initial strength. As a native 3-dimenssional collagen framework, purified porcine acellular dermal matrix (PADM) has been successfully used as a skin tissue engineering scaffold. Here we report its application as a matrix for the preparation of HAp to produce a bone tissue scaffold through a biomimetic chemical process. The HAp-PADM scaffold has two-level pore structure, with large channels (?100??m in diameter) inherited from the purified PADM microstructure and small pores (<100?nm in diameter) formed by self-assembled HAp on the channel surfaces. The obtained HAp-PADM scaffold (S15D) has a compressive elastic modulus as high as 600?kPa. The presence of HAp in sample S15D reduces the degradation rate of PADM in collagenase solution at 37°C. After 7 day culture of MC3T3-E1 pre-osteroblasts, MTT data show no statistically significant difference on pure PADM framework and HAp-PADM scaffold (p?>?0.05). Because of its high strength and nontoxicity, its simple preparation method, and designable and tailorable properties, the HAp-PADM scaffold is expected to have great potential applications in medical treatment of bone defects. PMID:20964580

Zhao, Hongshi; Wang, Guancong; Hu, Shunpeng; Cui, Jingjie; Ren, Na; Liu, Duo; Liu, Hong; Cao, Chengbo; Wang, Jiyang; Wang, Zhonglin

2011-03-01

388

77 FR 42677 - Special Conditions: General Electric CT7-2E1 Turboshaft Engine  

Federal Register 2010, 2011, 2012, 2013, 2014

...certification basis for CT7- 2E1 engine model is up to and including...standards are (1) Section A33.4, Airworthiness Limitations Section...Instruction manual for installing and operating the engine, paragraph (b)(4) Amendments 1-25. The...

2012-07-20

389

26 CFR 301.6230(e)-1 - Tax matters partner required to furnish names.  

Code of Federal Regulations, 2014 CFR

...2014-04-01 2014-04-01 false Tax matters partner required to furnish names. ...General § 301.6230(e)-1 Tax matters partner required to furnish names. ...administrative proceeding is mailed to the tax matters partner with respect to any...

2014-04-01

390

26 CFR 301.6230(e)-1 - Tax matters partner required to furnish names.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Tax matters partner required to furnish names. ...General § 301.6230(e)-1 Tax matters partner required to furnish names. ...administrative proceeding is mailed to the tax matters partner with respect to any...

2012-04-01

391

26 CFR 301.6230(e)-1 - Tax matters partner required to furnish names.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Tax matters partner required to furnish names. ...General § 301.6230(e)-1 Tax matters partner required to furnish names. ...administrative proceeding is mailed to the tax matters partner with respect to any...

2011-04-01

392

26 CFR 301.6230(e)-1 - Tax matters partner required to furnish names.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Tax matters partner required to furnish names. ...General § 301.6230(e)-1 Tax matters partner required to furnish names. ...administrative proceeding is mailed to the tax matters partner with respect to any...

2013-04-01

393

26 CFR 301.6230(e)-1 - Tax matters partner required to furnish names.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Tax matters partner required to furnish names. ...General § 301.6230(e)-1 Tax matters partner required to furnish names. ...administrative proceeding is mailed to the tax matters partner with respect to any...

2010-04-01

394

EXPRESSION AND CHARACTERIZATION OF ACIDOTHERMUS CELLULOLYTICUS E1 ENDOGLUCANASE IN TRANSGENIC DUCKWEED LEMNA MINOR 8627  

Technology Transfer Automated Retrieval System (TEKTRAN)

Endoglucanase E1 from Acidothermus cellulolyticus was expressed cytosolically under control of the cauliflower mosaic virus 35S promoter in transgenic duckweed, Lemna minor 8627. The selected transgenic duckweed line Cel25IX-15 generated using Agrobacterium-mediated transformation exhibited no phen...

395

Accretion Disk Turbulence By CHARLES F. GAMM I E 1;2  

E-print Network

Accretion Disk Turbulence By CHARLES F. GAMM I E 1;2 1 Isaac Newton Institute, 20 Clarkson Rd)r @ @r ` 1 r\\Omega @ @r (r 2 W rOE ) \\Gamma ø\\Omega ' \\Gamma â?? \\Sigma W ; (1.1) here\\Omega j orbital

Gammie, Charles F.

396

The effect of prostaglandin E1 analog misoprostol on chronic cyclosporin nephrotoxicity.  

PubMed

Cyclosporin A has markedly improved graft survival in transplant patients but its side effects, such as renal toxicity and hypertension, pose management problems in transplant recipients. This toxicity has been attributed to prostaglandin inhibition. Concurrent administration of misoprostol (a prostaglandin E1 analog) prevents chronic cyclosporin A-induced nephrotoxicity but not hypertension in rats. PMID:8301454

John, E G; Fornell, L C; Radhakrishnan, J; Anutrakulchai, S; Jonasson, O

1993-11-01

397

E-1 Dynamic Fluid-Flow Model Update: EASY/ROCETS Enhancement and Model Development Support  

NASA Technical Reports Server (NTRS)

This report documents the research conducted to update computer models for dynamic fluid flow simulation of the E-1 test stand subsystems at te NASA John C. Stennis Space Center.Work also involved significant upgrades to the capabilities of EASY/ROCKETS library through the inclusion of the NIST-12 thermodynamic property database and development of new control system modules.

Follett, Randolph F.; Taylor, Robert P.

1998-01-01

398

I-E-1 WORM GENOMIC DNA PREP I. GROWING THE WORMS  

E-print Network

I-E-1 WORM GENOMIC DNA PREP I. GROWING THE WORMS 1. Chunk worms onto a large DNA plates which have off worms with H20 after plate is close to or has starved and place in glass conical tube. 3. Wash worms twice with H20 to get rid of bacteria, and then transfer to an eppendorf tube. 4. Rinse worms

Bridgman, Paul C.

399

Study of molecular mechanism of Prostaglandin E1 in inhibiting coronary heart disease.  

PubMed

Prostaglandin E1 has been used clinically for improving heart diseases. In this study, we examined the effect of Prostaglandin E1 on blood lipid levels, heart protein and genes expression in coronary heart disease (CHD) rats. Female rats were fed either a control diet or hypercholesterolemic diet for 14 weeks. The feeding of a hypercholesterolemic diet (HCD) increased the serum TC, TG, and LDL-c levels, decreased the serum HDL-c, E2, P, FSH, LH and PRL levels in CHD rats. In addition, The feeding of a HCD diet markedly increased the content of serum TXA2, TXB2, and decreased the content of serum PGI2, and PGI2/TXA2, 6-Keto PGF1a. Furthermore, the feeding of a hypercholesterolemic diet markedly increased expression levels of myocardium Fas and Caspase-3 protein and mRNA levels, vascular endothelial growth factor and basic fibroblast growth factor mRNA, and decreased RyR2 mRNA in CHD rats. The feeding of Prostaglandin E1 for 14 weeks significantly reversed these abnormal biochemical indexes in rats. These findings suggest that Prostaglandin E1 play a obvious heart protective effect. The mechanisms may be related to restraining the excessive activation of Fas and Caspase-3 protein and modulating some gene expressions associated with CHD. PMID:24146100

Liu, H J; Ma, J W; Qiao, Z Y; Xu, B

2013-12-01

400

CYP2E1 is not involved in early alcohol-induced liver injury  

E-print Network

CYP2E1 is not involved in early alcohol-induced liver injury HIROSHI KONO,1 BLAIR U. BRADFORD,1 alcohol-induced liver injury. Am. J. Physiol. 277 (Gastrointest. Liver Physiol. 40): G1259­ G1267, 1999- induced liver injury (ALI) research. Much of what has been learned to date involves inhibitors

Omiecinski, Curtis

401

Lecture 15 Simulated Annealing and Genetic Algorithm Weinan E1,2  

E-print Network

Lecture 15 Simulated Annealing and Genetic Algorithm Weinan E1,2 and Tiejun Li2 1 Department, tieli@pku.edu.cn No.1 Science Building, 1575 #12;Introduction Simulated Annealing Genetic Algorithm Outline Introduction Simulated Annealing Genetic Algorithm #12;Introduction Simulated Annealing Genetic

Li, Tiejun

402

Phyllanthus urinaria extract attenuates acetaminophen induced hepatotoxicity: involvement of cytochrome P450 CYP2E1.  

PubMed

Acetaminophen is a commonly used drug for the treatment of patients with common cold and influenza. However, an overdose of acetaminophen may be fatal. In this study we investigated whether mice, administered intraperitoneally with a lethal dose of acetaminophen, when followed by oral administration of Phyllanthus urinaria extract, may be prevented from death. Histopathological analysis of mouse liver sections showed that Phyllanthus urinaria extract may protect the hepatocytes from acetaminophen-induced necrosis. Therapeutic dose of Phyllanthus urinaria extract did not show any toxicological phenomenon on mice. Immunohistochemical staining with the cytochrome P450 CYP2E1 antibody revealed that Phyllanthus urinaria extract reduced the cytochrome P450 CYP2E1 protein level in mice pre-treated with a lethal dose of acetaminophen. Phyllanthus urinaria extract also inhibited the cytochrome P450 CYP2E1 enzymatic activity in vitro. Heavy metals, including arsenic, cadmium, mercury and lead, as well as herbicide residues were not found above their detection limits. High performance liquid chromatography identified corilagin and gallic acid as the major components of the Phyllanthus urinaria extract. We conclude that Phyllanthus urinaria extract is effective in attenuating the acetaminophen induced hepatotoxicity, and inhibition of cytochrome P450 CYP2E1 enzyme may be an important factor for its therapeutic mechanism. PMID:19386480

Hau, Desmond Kwok Po; Gambari, Roberto; Wong, Raymond Siu Ming; Yuen, Marcus Chun Wah; Cheng, Gregory Yin Ming; Tong, Cindy Sze Wai; Zhu, Guo Yuan; Leung, Alexander Kai Man; Lai, Paul Bo San; Lau, Fung Yi; Chan, Andrew Kit Wah; Wong, Wai Yeung; Kok, Stanton Hon Lung; Cheng, Chor Hing; Kan, Chi Wai; Chan, Albert Sun Chi; Chui, Chung Hin; Tang, Johnny Cheuk On; Fong, David Wang Fun

2009-08-01

403

PRESIDENTIAL TASK FORCE SUSTAINING THE ACADEMIC PRIORITIES OF STFX 2013-2018 Pa g e | 1  

E-print Network

to serve best the goals of the University. What programs or units, academic or non-academic, administrativePRESIDENTIAL TASK FORCE SUSTAINING THE ACADEMIC PRIORITIES OF STFX 2013-2018 Pa g e | 1 a Presidential Task Force to identify and recommend avenues for sustaining the academic priorities

404

A&S 6/28/12 Form E-1-A for Boston College Undergraduate Programs  

E-print Network

in other disciplines in the liberal arts (literature, theology, music, dance, philosophy) and to applyA&S 6/28/12 Form E-1-A for Boston College Undergraduate Programs Program: Art History 1) Have of art in its entirety from pre-history to the present. 2) Ability to identify the medium, chronological

Huang, Jianyu

405

F i g u r e 1 : In QCD a confining flux tube forms  

E-print Network

Page 1 r F i g u r e 1 : In QCD a confining flux tube forms between distant static charges. The Hall D program is designed to verify this fundamental new feature of chromodynamics. q q /r F i g u r e 2 :Model­independent spectrum of the glue (flux tube) of Figure 1. ground state transverse phonon

406

Microcracking and engineering properties of high-strength concrete  

NASA Astrophysics Data System (ADS)

An X-ray technique was used to study internal microcracking. Two classification systems were developed to analyze the microcracks: bond-mortar crack analysis and simple-combined crack analysis. Internal microcracks were observed at four strain levels. The observed microcracking mechanism is related to the failure mode in uniaxial compression. The results of the mechanical properties study are presented including data on compressive strength, strength gain with age, specimen size effect, static modulus of elasticity, Poisson's ratio, modulus of rupture, tensile splitting strength, unit weight, and drying effect on compressive and flexural strength of normal- and high-strength concretes.

Carrasquillo, R. L.

1980-02-01

407

Chlormethiazole inhibition of cytochrome P450 2E1 as assessed by chlorzoxazone hydroxylation in humans.  

PubMed

Chlormethiazole is a sedative and anticonvulsive drug used in the treatment of alcohol withdrawal. Because it had been reported that chlormethiazole inhibits the alcohol-inducible cytochrome P450 2E1 in rat liver, we investigated the in vivo and in vitro effect of this drug on cytochrome P450 2E1 in human beings. The activity of this cytochrome was assessed using chlorzoxazone as a probe. The 6-hydroxychlorzoxazone-chlorzoxazone blood concentration ratio, reflecting the cytochrome P450 2E1 activity, was determined in 10 controls and in 24 alcoholic patients who had entered a hospital for detoxification. Alcoholic patients were administered either chlormethiazole (1.3-2.3 g/d) or chlorazepate (100-300 mg/d) as a sedative. Cytochrome P450 2E1 activity was significantly increased in alcoholic patients treated with chlorazepate (1.16 +/- 0.40 vs. 0.27 +/- 0.03, P < .05). In contrast, chlormethiazole treatment inhibited chlorzoxazone hydroxylation almost totally (0.046 +/- 0.03, P < .001). After 7-14 days of ethanol withdrawal, alcoholic patients treated with chlorazepate had ratio values similar to those of controls (0.31 +/- 0.05), whereas values from alcoholic patients treated with chlormethiazole remained low (0.049 +/- 0.01) even though chlormethiazole doses were gradually decreased. Pharmacokinetic studies in controls showed that chlormethiazole-mediated inhibition was present even when chlormethiazole was not detectable in the blood. In addition, the effect of chlormethiazole on cytochrome P450 2E1 was studied in vitro using human liver microsomes. Dixon plot analyses showed a noncompetitive inhibition (Ki = 12 micromol/L). These data clearly show that chlormethiazole is an efficient inhibitor of chlorzoxazone metabolism and thus of cytochrome P450 2E1 activity in human beings. Because cytochrome P450 2E1 induction after chronic ethanol consumption has detrimental effects on the liver through free radical formation, treatment of alcohol detoxification with chlormethiazole may be beneficial. PMID:9328319

Gebhardt, A C; Lucas, D; Ménez, J F; Seitz, H K

1997-10-01

408

Strength Development: Using Functional Isometrics in an Isotonic Strength Training Program.  

ERIC Educational Resources Information Center

A study was made to determine if a combination of functional isometrics and standard isotonic training would be superior to a standard isotonic program in an instructional setting. The results provide support for functional isometrics as an enhancement where achievement of maximum strength is the goal. (Author/MT)

Jackson, Allen; And Others

1985-01-01

409

Influence of steel fibres on strength and ductility of normal and lightweight high strength concrete  

Microsoft Academic Search

This paper presents the results of a series of experiments conducted to investigate the effectiveness of fibre inclusion in the improvement of mechanical performance of concrete with regard to concrete type and specimen size. Lightweight aggregate concrete and limestone aggregate concrete with and without steel fibres were used in the study. The compressive strength of the concrete mixes varied between

R. V Balendran; F. P Zhou; A Nadeem; A. Y. T Leung

2002-01-01

410

High strength cast aluminum alloy development  

NASA Astrophysics Data System (ADS)

The goal of this research was to understand how chemistry and processing affect the resulting microstructure and mechanical properties of high strength cast aluminum alloys. Two alloy systems were investigated including the Al-Cu-Ag and the Al-Zn-Mg-Cu systems. Processing variables included solidification under pressure (SUP) and heat treatment. This research determined the range in properties that can be achieved in BAC 100(TM) (Al-Cu micro-alloyed with Ag, Mn, Zr, and V) and generated sufficient property data for design purposes. Tensile, stress corrosion cracking, and fatigue testing were performed. CuAl2 and Al-Cu-Fe-Mn intermetallics were identified as the ductility limiting flaws. A solution treatment of 75 hours or longer was needed to dissolve most of the intermetallic CuAl 2. The Al-Cu-Fe-Mn intermetallic was unaffected by heat treatment. These results indicate that faster cooling rates, a reduction in copper concentration and a reduction in iron concentration might increase the ductility of the alloy by decreasing the size and amount of the intermetallics that form during solidification. Six experimental Al-Zn-Mg-Cu series alloys were produced. Zinc concentrations of 8 and 12wt% and Zn/Mg ratios of 1.5 to 5.5 were tested. Copper was held constant at 0.9%. Heat treating of the alloys was optimized for maximum hardness. Al-Zn-Mg-Cu samples were solution treated at 441°C (826°F) for 4 hours before ramping to 460°C (860°F) for 75 hours and then aged at 120°C (248°F) for 75 hours. X-ray diffraction showed that the age hardening precipitates in most of these alloys was the T phase (Mg32Zn 31.9Al17.1). Tensile testing of the alloys showed that the best mechanical properties were obtained in the lowest alloy condition. Chilled Al-8.2Zn-1.4Mg-0.9Cu solidified under pressure resulted in an alloy with a yield strength of 468MPa (68ksi), tensile strength of 525MPa (76ksi) and an elongation of 9%.

Druschitz, Edward A.

411

Explosive Strength Imbalances in Professional Basketball Players  

PubMed Central

Context: Despite the high rate of lower limb injuries in basketball players, studies of the dominant-limb effect in elite athletes often neglect injury history. Objective: To determine lower limb explosive-strength asymmetries in professional basketball players compared with junior basketball players and control participants. Design: Cohort study. Setting: Academic medical institution. Patients or Other Participants: 15 professional basketball players, 10 junior basketball players, and 20 healthy men. Main Outcome Measure(s): We performed an isokinetic examination to evaluate the knee extensor (Ext) and flexor (Fl) concentric peak torque at 60°·s?1 and 240°·s?1 and (Fl only) eccentric peak torque at 30°·s?1 and 120°·s?1. Functional evaluation included countermovement jump, countermovement jump with arms, 10-m sprint, single-leg drop jump, and single-leg, 10-second continuous jumping. Variables were compared among groups using analysis of variance or a generalized linear mixed model for bilateral variables. Results: The 2 groups of basketball players demonstrated better isokinetic and functional performances than the control group did. No differences in functional or relative isokinetic variables were noted between professional and junior basketball players. Professional players with a history of knee injury failed to reach normal knee extensor strength at 60°·s?1. Knee Ext (60°·s?1) and Fl (eccentric 120°·s?1) torque values as well as 10-second continuous jumping scores were higher in those professional players without a history of knee injury than those with such a history. Compared with the group without a history of knee injury, the group with a history of knee injury maintained leg asymmetry ratios greater than 10% for almost all isokinetic variables and more than 15% for unilateral functional variables. Conclusions: The relative isokinetic and functional performances of professional basketball players were similar to those of junior players, with no dominant-side effect. A history of knee injury in the professional athlete, however, was reflected in bilateral isokinetic and functional asymmetries and should be considered in future studies of explosive strength. PMID:19180217

Schiltz, Marc; Lehance, Cédric; Maquet, Didier; Bury, Thierry; Crielaard, Jean-Michel; Croisier, Jean-Louis

2009-01-01

412

Factors Contributing to Chronic Ankle Instability: A Strength Perspective  

PubMed Central

Objective: To examine the concept of dynamic ankle stability and closely critique the relevant research over the past 50+ years focusing on strength as it relates to those with chronic ankle instability (CAI). Data Sources: We reviewed the literature regarding the assessment of strength related to CAI. We searched MEDLINE and ISI Web of Science from 1950 through 2001 using the key words functional ankle instability, chronic ankle instability, strength, ankle stability, chronic ankle dysfunction, and isokinetics. Data Synthesis: An overview of dynamic stability in the ankle is established, followed by a comprehensive discussion involving the variables used to assess ankle strength. Additionally, a historical look at deficits in muscular stability leading to CAI is provided, and a compilation of numerous contemporary approaches examining strength as it relates to CAI is presented. Conclusions/Recommendations: Although strength is an important consideration during ankle rehabilitation, deficits in ankle strength are not highly correlated with CAI. More contemporary approaches involving the examination of reciprocal muscle-group ratios as a measure of strength have recently been investigated and offer an insightful, albeit different, avenue for future exploration. Evidence pertaining to the effects of strength training on those afflicted with CAI is lacking, including what, if any, implication strength training has on the various measures of ankle strength. PMID:12937561

Kaminski, Thomas W.; Hartsell, Heather D.

2002-01-01

413

Anthropometry and strength relationship: male-female differences.  

PubMed

Based upon 303 students from the Complutense University at Madrid (100 males and 203 females), aged between 21 and 29 years, the results of nine anthropometric measurements and four strength tests were evaluated. Males and females were analyzed separately in order to determine whether the relationship of body typology to physical performance varies according to gender. Regarding strength, maximum gender differences were observed for pulling strength (females: 53% of male values), followed by hand grip (59%) and vertical jump (66%). In general, correlations among variables were significant (anthropometric, strength, and anthropometric/strength). Principal component analysis revealed, that for women the vertical jump could be interpretated as more dependent on trunk length than on height or body size. Body size was relevant with respect to static strength. For males the vertical jump appeared to be more related to longitudinal dimensions than for females, while static strength had more to do with body mass (weight) than with body size (height). PMID:9569979

Fuster, V; Jerez, A; Ortega, A

1998-03-01

414

Chimeric Derivatives of Hepatitis B Virus Core Particles Carrying Major Epitopes of the Rubella Virus E1 Glycoprotein  

PubMed Central

Three variants of the major rubella virus (RV) E1 protein virus-neutralizing epitope from position 214 to 285 were exposed on the hepatitis B virus (HBV) C-terminally truncated core (HBc?) in a virus-like particle (VLP) vector and were produced in Escherichia coli. All three chimeras demonstrated VLPs in bacterial cell lysates, but only HBc?-E1(245-285) demonstrated the correct VLP structure after purification. The other chimeras, HBc?-E1(214-285) and HBc?-E1(214-240), appeared after purification as non-VLP aggregates of 100 to 900 nm in diameter according to dynamic light scattering data. All three variants possessed the intrinsic antigenic activity of RV E1, since they were recognized by natural human anti-RV E1 antibodies and induced an anti-RV E1 response in mice. HBc?-E1(214-240) and HBc?-E1(245-285) can be regarded as prototypes for a putative RV vaccine because they were able to induce antibodies recognizing natural RV E1 protein in RV diagnostic kits. PMID:24006140

Skrastina, Dace; Petrovskis, Ivars; Petraityte, Rasa; Sominskaya, Irina; Ose, Velta; Liekni?a, Ilva; Bogans, Janis; Sasnauskas, Kestutis

2013-01-01

415

Unreinforced sheeting material offers strength, chemical resistance  

SciTech Connect

The ability of multiple application structural or sheeting Teflon polytetrafluoroethylene (PTFE) material to function in severe chemical and mechanical environments at extreme temperatures garnered it a 1995 Chemical Processing Vaaler Award. The 100% Teflon PTFE resin yields sheeting with high levels of tear and tensile strength and a flex life that allows it to be used without additional support. The resin provides chemical resistance, heat sealability, simple fabrication, and rugged construction. The material functions in temperatures to 500 degrees F and has found many uses in the chemical industry like chemical tank covers, drop-in tank liners, flue gas barriers in non-metallic expansion joints, gasketing, pump diaphragms, insulating jacketing and pipe lagging, protective suiting materials, inflatable liners for chemical service, heat-sealed insulation jackets for severe chemical service and many others.

NONE

1995-10-01

416

Cobalt--For strength and color  

USGS Publications Warehouse

Cobalt is a shiny, gray, brittle metal that is best known for creating an intense blue color in glass and paints. It is frequently used in the manufacture of rechargeable batteries and to create alloys that maintain their strength at high temperatures. It is also one of the essential trace elements (or "micronutrients") that humans and many other living creatures require for good health. Cobalt is an important component in many aerospace, defense, and medical applications and is a key element in many clean energy technologies. The name cobalt comes from the German word kobold, meaning goblin. It was given this name by medieval miners who believed that troublesome goblins replaced the valuable metals in their ore with a substance that emitted poisonous fumes when smelted. The Swedish chemist Georg Brandt isolated metallic cobalt-the first new metal to be discovered since ancient times-in about 1735 and identified some of its valuable properties.

Boland, Maeve A.; Kropschot, S.J.

2011-01-01

417

Biomineral Structure and Strength of Barnacle Exoskeletons  

NASA Astrophysics Data System (ADS)

Studying the construction of organic-inorganic compound structures through biomineralization is potentially very useful. During biomineral formation, organisms restructure naturally occurring minerals in conjunction with their own organically produced minerals to create new structures. While there is extensive knowledge about material properties and structure of the raw minerals themselves, insight into how specific biomineral structures and compounds contribute to an object's mechanical properties is lacking. In this study, the exoskeletons of barnacles from the genus Balanus were examined, both for their physical structure (how they're put together) and for their mechanical properties (strength, hardness, and elasticity). Scanning electron microscopy produced close-up, detailed images of the inner shell structure to determine what type of structure barnacles build during exoskeleton formation. Energy dispersive x-ray spectroscopy was used to map the elemental components of the shells. Nanoindentation tested the mechanical properties of these mapped structures to determine how certain characteristics of the exoskeleton contribute to its mechanical properties.

Swift, Nathan

2011-03-01

418

High strength air-dried aerogels  

DOEpatents

A method for the preparation of high strength air-dried organic aerogels. The method involves the sol-gel polymerization of organic gel precursors, such as resorcinol with formaldehyde (RF) in aqueous solvents with R/C ratios greater than about 1000 and R/F ratios less than about 1:2.1. Using a procedure analogous to the preparation of resorcinol-formaldehyde (RF) aerogels, this approach generates wet gels that can be air dried at ambient temperatures and pressures. The method significantly reduces the time and/or energy required to produce a dried aerogel compared to conventional methods using either supercritical solvent extraction. The air dried gel exhibits typically less than 5% shrinkage.

Coronado, Paul R.; Satcher, Jr., Joe H.

2012-11-06

419

Attempt to control the interfacial strength  

SciTech Connect

Composites consisting of a B2 iron aluminide matrix and 40 vol.% of TiB{sub 2} particles were processed by liquid phase sintering. In order to encourage segregation of B or Ti at the FeAl/TiB{sub 2} interfaces, the iron aluminide matrix was microalloyed with B or Ti, respectively. Additions of Ti degraded the mechanical properties. However, for composites microalloyed with B, room temperature flexure tests show slight increases in the maximum strength (from 1250 to 1380 MPa) and the fracture toughness. Interfacial segregation of B may have contributed to this result. Significantly improved processing of the composites would be required in order to verify the effect of B conclusively. 15 refs., 6 figs., 2 tabs.

Schneibel, J.H. [Oak Ridge National Lab., TN (United States); Subramanian, R. [Westinghouse Power Generation, Orlando, FL (United States)

1997-11-01

420

Welding High Strength Modern Line Pipe Steel  

NASA Astrophysics Data System (ADS)

The effect of modern mechanized girth welding on high strength line pipe has been investigated. The single cycle grain coarsened heat affected zone in three grade 690 line pipe steels and a grade 550 steel has been simulated using a Gleeble thermo-mechanical simulator. The continuous cooling transformation diagrams applicable to the grain coarsened heat affected zone resulting from a range of heat inputs applicable to modern mechanized welding have been established by dilatometry and metallography. The coarse grained heat affected zone was found to transform to lath martensite, bainite, and granular bainite depending on the cooling rate. The impact toughness of the steels was measured using Charpy impact toughness and compared to the toughness of the grain coarsened heat affected zone corresponding to a welding thermal cycle. The ductile to brittle transition temperature was found to be lowest for the steel with the highest hardenability. The toughness resulting from three different thermal cycles including a novel interrupted intercritically reheated grain coarsened (NTR ICR GC HAZ) that can result from dual torch welding at fast travel speed and close torch spacing have been investigated. All of the thermally HAZ regions showed reduced toughness that was attributed to bainitic microstructure and large effective grain sizes. Continuous cooling transformation diagrams for five weld metal chemistries applicable to mechanized pulsed gas metal arc welding of modern high strength pipe steel (SMYS>550 MPa) have been constructed. Welds at heat inputs of 1.5 kJmm-1 and 0.5 kJmm-1 have been created for simulation and analysis. Dilatometric analysis was performed on weld metal specimens cut from single pass 1.5 kJmm-1 as deposited beads. The resulting microstructures were found to range from martensite to polygonal ferrite. There is excellent agreement between the simulated and as deposited weld metal regions. Toughness testing indicates improved energy absorption at -20 °C with increased cooling time.

Goodall, Graeme Robertson

421

Strength and failure of cemented granular matter  

NASA Astrophysics Data System (ADS)

Cemented granular materials (CGMs) consist of densely packed solid particles and a pore-filling solid matrix sticking to the particles. We use a sub-particle lattice discretization method to investigate the particle-scale origins of strength and failure properties of CGMs. We show that jamming of the particles leads to highly inhomogeneous stress fields. The stress probability density functions are increasingly wider for a decreasing matrix volume fraction, the stresses being more and more concentrated in the interparticle contact zones with an exponential distribution as in cohesionless granular media. Under uniaxial loading, pronounced asymmetry can occur between tension and compression both in strength and in the initial stiffness as a result of the presence of bare contacts (with no matrix interposed) between the particles. Damage growth is analyzed by considering the evolution of stiffness degradation and the number of broken bonds in the particle phase. A brutal degradation appears in tension as a consequence of brittle fracture in contrast to the more progressive nature of damage growth in compression. We also carry out a detailed parametric study in order to assess the combined influence of the matrix volume fraction and particle-matrix adherence. Three regimes of crack propagation can be distinguished corresponding to no particle damage, particle abrasion and particle fragmentation, respectively. We find that particle damage scales well with the relative toughness of the particle-matrix interface with respect to the particle toughness. This relative toughness is a function of both matrix volume fraction and particle-matrix adherence and it appears therefore to be the unique control parameter governing transition from soft to hard behavior.

Topin, V.; Delenne, J.-Y.; Radja?, F.; Brendel, L.; Mabille, F.

2007-08-01

422

Oscillator strengths and lifetimes in Ge XXI  

NASA Astrophysics Data System (ADS)

We have calculated energy splittings of 53 fine-structure levels as well as oscillator strengths and radiative decay rates for all electric-dipole-allowed and intercombination transitions among the (1s22s22p6)3s2(1S), 3s3p(1,3Po), 3s3d(1,3D), 3s4s(1,3S), 3s4p(1,3Po), 3s4d(1,3D), 3s4f(1,3Fo), 3p2(1S,3P,1D), 3p3d(1,3Po,1,3Do,1,3Fo), 3p4s(1,3Po) and 3d2(1S,3P,1D,3F,1G) states of Ge XXI, using extensive configuration-interaction (CI) wavefunctions, obtained with the CIV3 computer code of Hibbert. The important relativistic effects in intermediate coupling are incorporated by means of the Breit-Pauli Hamiltonian. In order to keep our calculated energy splittings as close as possible to the experimental values, we have made small adjustments to the diagonal elements of the Hamiltonian matrices. Our excitation energies, including their ordering, are in excellent agreement with the available experimental results. The enormous mixing among several fine-structure levels makes it very difficult to identify them correctly with the result that their positions in the calculation of Ivanova et al are interchanged compared to our results and the experimental values. From our transition probabilities, we have also calculated radiative lifetimes of some fine-structure levels. Our calculated oscillator strengths and the lifetimes are found to be in good agreement with the other available theoretical results. In this calculation, we also predict new data for several fine-structure levels where no other theoretical and/or experimental results are available.

Gupta, G. P.; Msezane, A. Z.

2008-03-01

423

Comparative study of Weibull characteristic strength and mean strength of GPCs to confirm the minimum number of samples needed for confident strength reporting.  

PubMed

This short communication determines the strength of two glass polyalkenoate cements that differ from each other through the composition of their glass phase. Sample sets of n=5, 10, 20 and 30 were formulated and tested in biaxial flexure. The derived mean for each sample set was compared against the Weibull characteristic strength. The mean and corresponding characteristic strength show a maximum percentage difference 10.1%, and the 95% confidence intervals calculated from the mean data encompass the corresponding characteristic strength down to a sample set of n=5. This suggests that, for brittle materials such as glass polyalkenoate cements, it is acceptable to test only five samples of each material in biaxial flexure and the resultant 95% confidence intervals will encompass the corresponding Weibull characteristic strength of the material. PMID:25553555

Mehrvar, Cina; Curran, Declan J; Alhalawani, Adel M F; Boyd, Daniel; Towler, Mark

2015-03-01

424

Intestinal CYP2E1: A mediator of alcohol-induced gut leakiness  

PubMed Central

Chronic alcohol use can result in many pathological effects including alcoholic liver disease (ALD). While alcohol is necessary for the development of ALD, only 20–30% of alcoholics develop alcoholic steatohepatitis (ASH) with progressive liver disease leading to cirrhosis and liver failure (ALD). This suggests that while chronic alcohol consumption is necessary it is not sufficient to induce clinically relevant liver damage in the absence of a secondary risk factor. Studies in rodent models and alcoholic patients show that increased intestinal permeability to microbial products like endotoxin play a critical role in promoting liver inflammation in ALD pathogenesis. Therefore identifying mechanisms of alcohol-induced intestinal permeability is important in identifying mechanisms of ALD and for designing new avenues for therapy. Cyp2e1 is a cytochrome P450 enzyme that metabolizes alcohol has been shown to be upregulated by chronic alcohol use and to be a major source of oxidative stress and liver injury in alcoholics and in animal and in vitro models of chronic alcohol use. Because Cyp2e1 is also expressed in the intestine and is upregulated by chronic alcohol use, we hypothesized it could play a role in alcohol-induced intestinal hyperpermeability. Our in vitro studies with intestinal Caco-2 cells and in mice fed alcohol showed that circadian clock proteins CLOCK and PER2 are required for alcohol-induced permeability. We also showed that alcohol increases Cyp2e1 protein and activity but not mRNA in Caco-2 cells and that an inhibitor of oxidative stress or siRNA knockdown of Cyp2e1 prevents the increase in CLOCK or PER2 proteins and prevents alcohol-induced hyperpermeability. With our collaborators we have also shown that Cyp2e1 knockout mice are resistant to alcohol-induced gut leakiness and liver inflammation. Taken together our data support a novel Cyp2e1-circadian clock protein mechanism for alcohol-induced gut leakiness that could provide new avenues for therapy of ALD. PMID:25462064

Forsyth, Christopher B.; Voigt, Robin M.; Keshavarzian, Ali.

2014-01-01

425

Hamstrings strength imbalance in professional football (soccer) players in Australia.  

PubMed

The aim of this study was to describe the isokinetic thigh muscle strength profile of professional male football players in Australia. Concentric (60° and 240°/second) and eccentric (30° and 120°/second) hamstrings and quadriceps isokinetic strength was measured with a HUMAC NORM dynamometer. The primary variables were bilateral concentric and eccentric hamstring and quadriceps peak torque ratios, concentric hamstring-quadriceps peak torque ratios, and mixed ratios (eccentric hamstring 30°/second ÷ concentric quadriceps 240°/second). Hamstring strength imbalance was defined as deficits in any two of: bilateral concentric hamstring peak torque ratio < 0.86, bilateral eccentric hamstring peak torque ratio < 0.86, concentric hamstring-quadriceps ratio < 0.47, mixed ratio < 0.80. Fifty-five strength tests involving 42 players were conducted. Ten players (24%) were identified as having hamstring strength imbalance. Athletes with strength imbalance had significantly reduced concentric and eccentric bilateral hamstring peak torque ratios at all angular velocities tested; and reduced eccentric quadriceps peak torque (30°/second) in their stance leg, compared to those without strength imbalance. Approximately one in four players had preseason hamstring strength imbalance; and all strength deficits were observed in the stance leg. Concentric and eccentric hamstrings strength imbalance may impact in-season football performance, and could have implications for the future risk of injury. PMID:25426513

Ardern, Clare L; Pizzari, Tania; Wollin, Martin; Webster, Kate E

2014-11-25

426

Age and grip strength predict hand dexterity in adults.  

PubMed

In the scientific literature, there is much evidence of a relationship between age and dexterity, where increased age is related to slower, less nimble and less smooth, less coordinated and less controlled performances. While some suggest that the relationship is a direct consequence of reduced muscle strength associated to increased age, there is a lack of research that has systematically investigated the relationships between age, strength and hand dexterity. Therefore, the aim of this study was to examine the associations between age, grip strength and dexterity. 107 adults (range 18-93 years) completed a series of hand dexterity tasks (i.e. steadiness, line tracking, aiming, and tapping) and a test of maximal grip strength. We performed three phases of analyses. Firstly, we evaluated the simple relationships between pairs of variables; replicating the existing literature; and found significant relationships of increased age and reduced strength; increased age and reduced dexterity, and; reduced strength and reduced dexterity. Secondly, we used standard Multiple Regression (MR) models to determine which of the age and strength factors accounted for the greater variance in dexterity. The results showed that both age and strength made significant contributions to the data variance, but that age explained more of the variance in steadiness and line tracking dexterity, whereas strength explained more of the variance in aiming and tapping dexterity. In a third phase of analysis, we used MR analyses to show an interaction between age and strength on steadiness hand dexterity. Simple Slopes post-hoc analyses showed that the interaction was explained by the middle to older aged adults showing a relationship between reduced strength and reduced hand steadiness, whereas younger aged adults showed no relationship between strength and steadiness hand dexterity. The results are discussed in terms of how age and grip strength predict different types of hand dexterity in adults. PMID:25689161

Martin, Jason A; Ramsay, Jill; Hughes, Christopher; Peters, Derek M; Edwards, Martin G

2015-01-01

427

Strength development of high-strength ductile concrete incorporating Metakaolin and PVA fibers.  

PubMed

The mechanical properties of high-strength ductile concrete (HSDC) have been investigated using Metakaolin (MK) as the cement replacing material and PVA fibers. Total twenty-seven (27) mixes of concrete have been examined with varying content of MK and PVA fibers. It has been found that the coarser type PVA fibers provide strengths competitive to control or higher than control. Concrete with coarser type PVA fibers has also refined microstructure, but the microstructure has been undergone with the increase in aspect ratio of fibers. The microstructure of concrete with MK has also more refined and packing of material is much better with MK. PVA fibers not only give higher stiffness but also showed the deflection hardening response. Toughness Index of HSDC reflects the improvement in flexural toughness over the plain concrete and the maximum toughness indices have been observed with 10% MK and 2% volume fraction of PVA fibers. PMID:24707202

Nuruddin, Muhammad Fadhil; Khan, Sadaqat Ullah; Shafiq, Nasir; Ayub, Tehmina

2014-01-01

428

Strength Development of High-Strength Ductile Concrete Incorporating Metakaolin and PVA Fibers  

PubMed Central

The mechanical properties of high-strength ductile concrete (HSDC) have been investigated using Metakaolin (MK) as the cement replacing material and PVA fibers. Total twenty-seven (27) mixes of concrete have been examined with varying content of MK and PVA fibers. It has been found that the coarser type PVA fibers provide strengths competitive to control or higher than control. Concrete with coarser type PVA fibers has also refined microstructure, but the microstructure has been undergone with the increase in aspect ratio of fibers. The microstructure of concrete with MK has also more refined and packing of material is much better with MK. PVA fibers not only give higher stiffness but also showed the deflection hardening response. Toughness Index of HSDC reflects the improvement in flexural toughness over the plain concrete and the maximum toughness indices have been observed with 10% MK and 2% volume fraction of PVA fibers. PMID:24707202

Nuruddin, Muhammad Fadhil; Shafiq, Nasir

2014-01-01

429

PP2A-B55? Antagonizes Cyclin E1 Proteolysis and Promotes its Dysregulation in Cancer  

PubMed Central

Cyclin E1 regulates the initiation of S phase in cellular division. However, in many cancers cyclin E1 is aberrantly overexpressed and this molecular phenotype correlates with increased tumor aggressiveness and poor patient survival. The molecular cause(s) of cyclin E1 abnormalities in cancers is poorly understood. Here, we show cyclin E1 overexpression in cancer is promoted by dysregulation of the protein phosphatase PP2A-B55?. PP2A-B55? targets the N- and C-terminal phosphodegrons of cyclin E1 for dephosphorylation, thus protecting it from degradation mediated by the SCFFbxw7 ubiquitin ligase. Augmented B55? expression stabilizes cyclin E1 and promotes its overexpression in cancer-derived cell lines and breast tumors. Conversely, B55? ablation enforces the degradation of cyclin E1 and inhibits cancer cell proliferation in vitro and tumor formation in vivo. Therefore, PP2A-B55? promotes cyclin E1 overexpression by antagonizing its degradation and its inhibition could represent a therapeutic mechanism for abrogating cyclin E1 function in cancers. PMID:24509904

Tan, YingMeei; Sun, Dahui; Jiang, Weijian; Klotz-Noack, Kathleen; Vashisht, Ajay A.; Wohlschlegel, James; Widschwendter, Martin; Spruck, Charles

2014-01-01

430

The DprE1 enzyme, one of the most vulnerable targets of Mycobacterium tuberculosis.  

PubMed

The re-emergence of tuberculosis in recent years led the World Health Organization (WHO) to launch the Stop TB Strategy program. Beside repurposing the existing drugs and exploring novel molecular combinations, an essential step to face the burden of tuberculosis will be to develop new drugs by identifying vulnerable bacterial targets. Recent studies have focused on decaprenylphosphoryl-D-ribose oxidase (DprE1) of Mycobacterium tuberculosis, an essential enzyme involved in cell wall metabolism, for which new promising molecules have proved efficacy as antitubercular agents. This review summarizes the state of the art concerning DprE1 in terms of structure, enzymatic activity and inhibitors. This enzyme is emerging as one of the most vulnerable target in M. tuberculosis. PMID:24037308

Riccardi, Giovanna; Pasca, Maria Rosalia; Chiarelli, Laurent Roberto; Manina, Giulia; Mattevi, Andrea; Binda, Claudia

2013-10-01

431

Nicotinamide N-Oxidation by CYP2E1 in Human Liver Microsomes  

PubMed Central

Excess nicotinamide, a form of vitamin B3, is metabolized through two enzymatic systems and eventually excreted from the body. The first system starts with the methylation of nicotinamide by nicotinamide N-methyltransferase, which can subsequently be oxidized by aldehyde oxidase. The second enzymatic system oxidizes nicotinamide to nicotinamide N-oxide. It is located in the endoplasmic reticulum of hepatocytes but the precise enzyme is unknown. We have used human liver microsomes in combination with selective cytochrome P450 inhibitors, specific substrates, and antibodies to identify CYP2E1 as the main activity producing nicotinamide N-oxide. Our results suggest the potential use of nicotinamide N-oxide as a biomarker of CYP2E1 activity from urine or blood samples. PMID:23418369

Real, Alexander Michael; Hong, Shangyu

2013-01-01

432

The effect of carbohydrate mouth rinse on maximal strength and strength endurance  

Microsoft Academic Search

It has been previously reported that carbohydrate (CHO) mouth rinse can improve exercise performance. The proposed mechanism\\u000a involves increased activation of brain regions believed to be responsible for reward\\/motivation and motor control. Since strength-related\\u000a performance is affected by central drive to the muscles, it seems reasonable to hypothesize that the positive CNS response\\u000a to oral CHO sensing may counteract the

Vitor S. Painelli; Bruno Gualano; Serena Del-Favero; Fabiana B. Benatti; Carlos Ugrinowitsch; Valmor Tricoli; Antonio H. Lancha

433

Strength of the Spontaneously Emitted Collective Aperiodic Magnetic Field Fluctuations in the Reionized Early Intergalactic Medium  

NASA Astrophysics Data System (ADS)

Nonmagnetized, fully ionized plasmas spontaneously emit aperiodic turbulent magnetic field fluctuations. Its fluctuation intensities are dominated by the contribution from a recently discovered collective, damped mode, which modifies the earlier estimate of the total magnetic field strength in a thermal nonrelativistic electron-proton plasma to |\\delta B|=24\\beta _e^{1/4}(gn_em_ec^2)^{1/2} G, where g denotes the plasma parameter and ? e the thermal electron velocity in units of the speed of light, in the case of no collisional damping. Accounting for simultaneous viscous damping reduces the estimate to |?B|eq = 2305g(nemec 2)1/2 G, depending only on the plasma parameter g and the electron density ne . For the unmagnetized intergalactic medium, immediately after the reionization onset the field strengths from this mechanism are about 6.8 × 10-13 G for no collisional damping and 1.5 × 10-16 G for viscous damping. Maximum spatial scales of 1015 cm of the emitted aperiodic fluctuations in cosmic voids are possible.

Schlickeiser, R.; Felten, T.

2013-11-01

434

Biochemical and genetic studies of four patients with pyruvate dehydrogenase E1? deficiency  

Microsoft Academic Search

We report studies of four patients with pyruvate dehydrogenase complex (PDH) deficiency caused by mutations in the E1? subunit.\\u000a Two unrelated male patients presented with Leigh syndrome and a R263G missense mutation in exon 8. This mutation has previously\\u000a been described in males with the same phenotype. The two other patients had different novel mutations: (1) an 8-bp deletion\\u000a at

Cécile Marsac; Chantal Benelli; Isabelle Desguerre; Monique Diry; Françoise Fouque; Linda De Meirleir; Gérard Ponsot; Sara Seneca; Florence Poggi; Jean-Marie Saudubray; Marie-Thérèse Zabot; Daniel Fontan; Willy Lissens

1997-01-01

435

Simvastatin Promotes Osteoblast Differentiation and Mineralization in MC3T3-E1 Cells  

Microsoft Academic Search

The cholesterol-lowering drug, simvastatin, is a pro-drug of a potent 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor and inhibits cholesterol synthesis in humans and animals. In addition, the bone effects of statins including simvastatin are being studied. We assessed the effects of simvastatin on osteoblastic differentiation in nontransformed osteoblastic cells (MC3T3-E1) and rat bone marrow cells. Simvastatin enhanced alkaline phosphatase (ALP) activity

Toyonobu Maeda; Ayako Matsunuma; Tetsuya Kawane; Noboru Horiuchi

2001-01-01

436

Stimulatory effect of daidzein in osteoblastic MC3T3-E1 cells  

Microsoft Academic Search

Daidzein is a natural isoflavone found in Leguminosae. The effect of daidzein on osteoblastic MC3T3-E1 cells was investigated. Cells were cultured in a serum-free medium for 48 hr in the presence of daidzein (10?7–10?5 M). Daidzein (10?6 and 10?5 M) caused a significant elevation of protein content, alkaline phosphatase activity, and DNA content in cells; those increases were about 1.4-,

Emi Sugimoto; Masayoshi Yamaguchi

2000-01-01

437

Induction of Calcification in MC3T3-E1 Cells by Inorganic Polyphosphate  

Microsoft Academic Search

Relatively large amounts of inorganic polyphosphate [poly(P)] (400 ?M) have been found in normal osteoblasts. The effect of poly(P) with an average chain length of 65 phosphate residues on cell calcification was therefore investigated with the use of MC3T3-E1 cells. Expression of both osteopontin and osteocalcin was induced by poly(P) (0.1 ~ 1 mM), and cells treated with poly(P) were

Y. Kawazoe; T. Shiba; R. Nakamura; A. Mizuno; K. Tsutsumi; T. Uematsu; M. Yamaoka; M. Shindoh; T. Kohgo

2004-01-01

438

Selective allylic hydroxylation of acyclic terpenoids by CYP154E1 from Thermobifida fusca YX  

PubMed Central

Summary Allylic alcohols are valuable precursors in the synthesis of pharmaceutical intermediates, agrochemicals and natural products. Regioselective oxidation of parental alkenes is a challenging task for chemical catalysts and requires several steps including protection and deprotection. Many cytochrome P450 enzymes are known to catalyse selective allylic hydroxylation under mild conditions. Here, we describe CYP154E1 from Thermobifida fusca YX that enables this type of oxidation. Several acyclic terpenoids were tested as possible substrates for CYP154E1, and the regio- and chemoselectivity of their oxidation was investigated. Using a previously established bioinformatics approach we identified position 286 in the active site of CYP154E1 which is putatively involved in substrate binding and thereby might have an effect on enzyme selectivity. To tune regio- and chemoselectivity of the enzyme three mutants at position 286 were constructed and used for substrate oxidation. All formed products were analysed with GC–MS and identified using chemically synthesised authentic samples and known compounds as references. Best regioselectivity towards geraniol and nerol was observed with the wild type enzyme mainly leading to 8-hydroxy derivatives (8-hydroxygeraniol or 8-hydroxynerol) with high selectivity (100% and 96% respectively). Highest selectivities during the oxidation of geranylacetone and nerylacetone were observed with the following variants: V286F led mainly to 7-hydroxygeranylacetone (60% of the total product) and V286A produced predominantly 12-hydroxynerylacetone (75% of total product). Thus, CYP154E1 and its mutants expand the tool-box for allylic hydroxylation in synthetic chemistry. PMID:24991288

Kriening, Sebastian; Busch, Alexandrine; Seifert, Alexander; Pleiss, Jürgen; Laschat, Sabine

2014-01-01

439

Inhibition of cytochrome P4502E1 by chlormethiazole attenuated acute ethanol-induced fatty liver.  

PubMed

Cytochrome P4502E1 (CYP2E1) has been demonstrated to play crucial roles in chronic ethanol-induced fatty liver, while its role in acute ethanol-induced fatty liver remains unclear. The current study was designed to evaluate the effects of chlormethiazole (CMZ), a specific inhibitor of CYP2E1, on acute ethanol-induced fatty liver, and to explore the mechanisms. Mice were pretreated with single dose of CMZ (50mg/kg body weight) by intraperitoneal injection or equal volume of saline, and then exposed to three doses of ethanol (5g/kg body weight, 25%, w/v) by gavage with 12h intervals. The mice were sacrificed at 4h after the last ethanol dosing. It was found that CMZ significantly attenuated acute ethanol-induced increase of the hepatic and serum triglyceride levels, and reduced fat droplets accumulation in mice liver. Acute ethanol-induced increase of the hepatic malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE) levels (two biomarkers for oxidative stress) and decrease of glutathione (GSH) level was significantly suppressed by CMZ. CMZ also suppressed ethanol-induced decline of serum adiponectin level, but did not significantly affect the serum tumor necrosis factor-? (TNF-?) and ethanol levels. Furthermore, a significant decline of p62 protein level was observed in CMZ/ethanol group mice liver compared with that of the ethanol group mice. However, acute ethanol-induced increase of peroxisome proliferator-activated receptor ? (PPAR-?) protein level was suppressed by CMZ, while the protein levels of sterol regulatory element-binding protein-1c (SREBP-1) and diacylglycerol acyltransferase 2 (DGAT2) were not significantly affected by ethanol or CMZ. Collectively, the results of the current study demonstrated that CMZ could effectively attenuate acute ethanol-induced fatty liver possibly by suppressing oxidative stress and adiponectin decline, and activating autophagy, which suggest that CYP2E1 might also play important roles in acute ethanol-induced fatty liver. PMID:25162931

Chen, Yang-Yang; Zhang, Cui-Li; Zhao, Xiu-Lan; Xie, Ke-Qin; Zeng, Tao

2014-08-24

440

Mouse Spermatocytes Express CYP2E1 and Respond to Acrylamide Exposure  

PubMed Central

Metabolism of xenobiotics by cytochrome P450s (encoded by the CYP genes) often leads to bio-activation, producing reactive metabolites that interfere with cellular processes and cause DNA damage. In the testes, DNA damage induced by xenobiotics has been associated with impaired spermatogenesis and adverse effects on reproductive health. We previously reported that chronic exposure to the reproductive toxicant, acrylamide, produced high levels of DNA damage in spermatocytes of Swiss mice. CYP2E1 metabolises acrylamide to glycidamide, which, unlike acrylamide, readily forms adducts with DNA. Thus, to investigate the mechanisms of acrylamide toxicity in mouse male germ cells, we examined the expression of the CYP, CYP2E1, which metabolises acrylamide. Using Q-PCR and immunohistochemistry, we establish that CYP2E1 is expressed in germ cells, in particular in spermatocytes. Additionally, CYP2E1 gene expression was upregulated in these cells following in vitro acrylamide exposure (1 µM, 18 h). Spermatocytes were isolated and treated with 1 µM acrylamide or 0.5 µM glycidamide for 18 hours and the presence of DNA-adducts was investigated using the comet assay, modified to detect DNA-adducts. Both compounds produced significant levels of DNA damage in spermatocytes, with a greater response observed following glycidamide exposure. A modified comet assay indicated that direct adduction of DNA by glycidamide was a major source of DNA damage. Oxidative stress played a small role in eliciting this damage, as a relatively modest effect was found in a comet assay modified to detect oxidative adducts following glycidamide exposure, and glutathione levels remained unchanged following treatment with either compound. Our results indicate that the male germ line has the capacity to respond to xenobiotic exposure by inducing detoxifying enzymes, and the DNA damage elicited by acrylamide in male germ cells is likely due to the formation of glycidamide adducts. PMID:24788432

Nixon, Belinda J.; Katen, Aimee L.; Stanger, Simone J.; Schjenken, John E.; Nixon, Brett; Roman, Shaun D.

2014-01-01

441

Strength and conditioning practices of National Hockey League strength and conditioning coaches.  

PubMed

This study describes the results of a survey of the practices of National Hockey League strength and conditioning (NHL S&C) coaches. The response rate was 76.6% (23 of 30). This survey examines (a) background information, (b) physical testing, (c) flexibility development, (d) speed development, (e) plyometrics, (f) strength/power development, (g) unique aspects, and (h) comments. Results indicate, in part, that coaches assess an average of 7.2 parameters of fitness, with tests of strength and power being the most common. All coaches used a variety of flexibility-development strategies. Results reveal that 21 of 23 (91.3%) of NHL S&C coaches follow a periodization model (PM). Of the coaches who follow a PM, 21 of 21 (100%) indicated that their athletes used Olympic-style lifts, and 21 of 21 coaches (100%) trained athletes with plyometric exercises. For those who used plyometrics with their athletes, 17 of 21 (80.1%) reported no plyometric-related injuries in the past year. Coaches who report they did not follow a PM also did not use Olympic-style lifts, plyometrics, or speed development strategies, such as assisted, resisted, or interval training, with their athletes. Finally, coaches reported that the squat and their variations, as well at the Olympic-style lifts and its variations, were most frequently used with their athletes. The survey serves as a review, as well as a source of applied information and new ideas. PMID:15574099

Ebben, William P; Carroll, Ryan M; Simenz, Christopher J

2004-11-01

442

Strength and conditioning practices of Major League Baseball strength and conditioning coaches.  

PubMed

This study describes the results of a survey of the practices of Major League Baseball strength and conditioning (MLB S&C) coaches. The response rate was 70.0% (21 of 30). This survey examines (a) background information, (b) physical testing, (c) flexibility development, (d) speed development, (e) plyometrics, (f) strength/power development, (g) unique aspects, and (h) comments. Results indicate, in part, that coaches assess an average of 3.6 parameters of fitness, with body composition testing being the most commonly assessed parameter. All coaches use a variety of flexibility development strategies. All coaches use speed development strategies, with form running drills being the most common. Twenty of 21 (95.2%) coaches employ plyometric exercises with their athletes. Eighteen of 21 (85.7%) of MLB S&C coaches follow a periodization model (PM). Five of 21 coaches (23.8%) indicated that their athletes use Olympic-style lifts. The squat and its variations and the lunge and its variations were most frequently identified as the first and second most important exercises used to train the athletes. This survey provides detailed information about strength and conditioning practices at the most competitive level of baseball and serves as a review, as well as a source of applied information and new ideas. PMID:16095401

Ebben, William P; Hintz, Marilyn J; Simenz, Christopher J

2005-08-01

443

Strength and conditioning practices of National Football League strength and conditioning coaches.  

PubMed

This article describes the results of a survey of the practices of National Football League strength and conditioning (NFL S&C) coaches. The response rate was 87% (26 of 30). This survey examines survey participant (a) background information, (b) physical testing, (c) flexibility development, (d) speed development, (e) plyometrics, (f) strength/power development, (g) unique aspects, and (h) comments. Results reveal that 18 of 26 (69%) NFL S&C coaches follow a periodization model (PM). Of these coaches, 14 of 16 (88%) who responded to the question reported their athletes used Olympic-style lifts, and 17 of 18 coaches (94%) employed plyometric exercises. Coaches who reported following a PM tested an average of 9.8 variables of fitness, which is an average of 3.55 times per year. Seven of 26 (27%) NFL S&C coaches did not follow a PM (NPM). Five of 7 (71%) of these coaches reported following "high-intensity training" (HIT) principles. None of these coaches reported using Olympic-style lifts. Two of 7 (29%) reported using plyometrics. NFL S&C coaches who follow an NPM reported testing an average of 2.12 variables of fitness, which is an average of 2 times per year. A variety of other strength and conditioning practices were examined. PMID:11708706

Ebben, W P; Blackard, D O

2001-02-01

444

Impact strength on fiber-reinforced hybrid composite  

NASA Astrophysics Data System (ADS)

Acrylonitrile-Butadiene-Styrene (ABS) has been well known composite in automotive players to have light weight with high impact strength material compared to sheet metal material which has high impact strength but heavy in weight. In this project, the impact strength properties of fabricated pure ABS were compared to the eight samples of hybrid ABS composite with different weight percentages of short fibers and particle sizes of ground rubber. The objective was to improve the impact strength in addition of short fibers and ground rubber particles. These samples were then characterized using an un-notched Izod impact test. Results show that the increasing of filler percentage yielded an adverse effect on the impact strength of the hybrid composite. The effect of the ground rubber particulate sizes however are deemed to be marginal than the effect of varying filler percentage based on the collected impact strength data from all physically tested hybrid composites.

Firdaus, S. M.; Nurdina; Azmil Ariff, M.

2013-12-01

445

A probability model for the strength of carbon nanotubes  

NASA Astrophysics Data System (ADS)

A longstanding controversy exists on the form of the probability distribution for the strength of carbon nanotubes: is it Weibull, lognormal, or something else? We present a theory for CNT strength through integration of weakest link scaling, flaw statistics, and brittle fracture. The probability distribution that arises exhibits multiple regimes, each of which takes the form of a Weibull distribution. Our model not only gives a possible resolution to the debate but provides a way to attain reliable estimates of CNT strength for materials design from practical-sized (non-asymptotic) data sets of CNT strength. Last, the model offers an explanation for the severe underestimation of CNT strength from strength tests of CNT bundles.

Xu, X. Frank; Jie, Yuxin; Beyerlein, Irene J.

2014-07-01

446

Compressive Strength of Stainless-Steel Sandwiches at Elevated Temperatures  

NASA Technical Reports Server (NTRS)

Experimental results are presented from crippling tests of stainless-steel sandwich specimens in the temperature range from 80 F to 1,200 F. The specimens included resistance-welded 17-7 PH stainless-steel sandwiches with single-corrugated cores, type 301 stainless-steel sandwiches with double-corrugated cores, and brazed 17-7 PH stainless-steel sandwiches with honeycomb cores. The experimental strengths are compared with predicted buckling and crippling strengths. The crippling strengths were predicted from the calculated maximum strength of the individual plate elements of the sandwiches and from a correlation procedure which gives the elevated-temperature crippling strength when the experimental room-temperature crippling strengths are known. Photographs of some of the tested specimens are included to show the modes of failure.

Mathauser, Eldon E.; Pride, Richard A.

1959-01-01

447

Effects of 6-Hydroxyflavone on Osteoblast Differentiation in MC3T3-E1 Cells  

PubMed Central

Osteoblast differentiation plays an essential role in bone integrity. Isoflavones and some flavonoids are reported to have osteogenic activity and potentially possess the ability to treat osteoporosis. However, limited information concerning the osteogenic characteristics of hydroxyflavones is available. This study investigates the effects of various hydroxyflavones on osteoblast differentiation in MC3T3-E1 cells. The results showed that 6-hydroxyflavone (6-OH-F) and 7-hydroxyflavone (7-OH-F) stimulated ALP activity. However, baicalein and luteolin inhibited ALP activity and flavone showed no effect. Up to 50??M of each compound was used for cytotoxic effects study; flavone, 6-OH-F, and 7-OH-F had no cytotoxicity on MC3T3-E1 cells. Moreover, 6-OH-F activated AKT and serine/threonine kinases (also known as protein kinase B or PKB), extracellular signal-regulated kinases (ERK 1/2), and the c-Jun N-terminal kinase (JNK) signaling pathways. On the other hand, 7-OH-F promoted osteoblast differentiation mainly by activating ERK 1/ 2 signaling pathways. Finally, after 5 weeks of 6-OH-F induction, MC3T3-E1 cells showed a significant increase in the calcein staining intensity relative to merely visible mineralization observed in cells cultured in the osteogenic medium only. These results suggested that 6-OH-F could activate AKT, ERK 1/2, and JNK signaling pathways to effectively promote osteoblastic differentiation. PMID:24795772

Wu, Yu-Wei; Yeh, Shauh-Der; Lin, Yu-Hsaing; Tsai, Yu-Hui

2014-01-01

448

A simple technique for early in vivo electroporation of E1 chick embryos  

PubMed Central

Background The amenability of the chick embryo to a variety of manipulations has made it an ideal experimental model organism for over 100 years. The ability to manipulate gene function via in ovo electroporations has further revolutionized its value as an experimental model in the last 1½ decades. Although in ovo electroporations are simple to conduct in embryos ? E2, in ovo electroporations at early E1 stages have proven to be technically challenging due to the tissue damage and embryonic lethality such electroporations produce. Results and Conclusions Here we report our success with in vivo microelectroporations of E1 embryos as young as Hamburger-Hamilton Stage 4 (HH4). We provide evidence that such electroporations can be varied in size and can be spatially targeted. They cause minimal disruption of tissue size, 3-dimensional morphology, cell survival, proliferation and cell-fate specification. Our paradigm is easily adapted to a variety of experimental conditions since it does not depend upon the presence of a lumen to enclose the DNA solution during electroporation. It is thus compatible with the in vivo examination of E1 morphogenetic events (e.g., neural tube closure) where preservation of 3-dimensional morphology is critical. PMID:22274994

Brown, Charmaine Y.; Eom, Dae Seok; Amarnath, Smita; Agarwala, Seema

2012-01-01

449

HOXA7 stimulates human hepatocellular carcinoma proliferation through cyclin E1/CDK2.  

PubMed

HOX genes are transcription factors that control morphogenesis, organogenesis and differentiation. Increasing evidence suggests that HOX genes play a role in hepatocellular carcinoma (HCC) progression; however few studies have defined the functional roles and mechanisms of action. In the present study, we used siRNA and forced-expression in multiple cell lines to define the role of HOXA7 in the regulation of proliferation of HCC in vitro and in vivo. Knockdown of endogenous HOXA7 decreased the proliferation of HepG2 and QGY-7703 cells. These changes were not associated with significant changes in cyclin D1 and CDK4. However, downregulation of HOXA7 significantly reduced cyclin E1 and CDK2 protein levels. Conversely, overexpression of HOXA7 in QSG-7701 cells stimulated proliferation and increased cyclin E1 and CDK2 protein levels. Our results confirmed that HOXA7 promoted cell proliferation, and these changes were mediated by cyclin E1/CDK2. These observations contribute to our understanding of the important roles of HOXA7 in HCC development and progression and HOXA7 could be a promising molecular target for the development of new diagnostic and therapeutic strategies for HCC. PMID:25501982

Li, Yuehui; Yang, Xiao Hui; Fang, Shu Juang; Qin, Chang Fei; Sun, Rui Li; Liu, Zhao Yang; Jiang, Bin Yuan; Wu, Xiang; Li, Guancheng

2015-02-01

450

Contribution of CYP2E1 polymorphism to aging in the mechanical workshop workers.  

PubMed

Aging is attributed to both genetic and environmental factors. Occupational exposure is one of the environmental factors with potential genotoxic effects. Researchers try to determine factors involved in genetic damages at hazards exposure that could accelerate aging. Cytochrome P450 2E1 (CYP2E1) gene contributes in activation and detoxification of the environmental hazards. This polymorphism plays an important role in susceptibility of inter-individuals to DNA damage at the occupational exposure. The current study evaluated the possible influence of this gene polymorphism in aging by genomic damages through the biomarkers alterations of micronuclei (MN), comet tail length and telomere length shortening at the exposure. In this study, buccal cells were collected from the oral cavity of exposed workers and non-exposed controls. The CYP2E1 genotypes were detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The wild genotype significantly affected MN frequency (p?=?0.007) and relative telomere length (p?=?0.047) in the older group of workers. It was concluded that the interaction of gene polymorphism and exposure enhances DNA damage and accelerates aging consequently. PMID:23193996

Eshkoor, Sima Ataollahi; Ismail, Patimah; Rahman, Sabariah Abd; Adon, Mohd Yusoff; Devan, R Vasu

2013-05-01

451

Shear bond strength of resin composite bonded with two adhesives: Influence of Er: YAG laser irradiation distance  

PubMed Central

Background: Dental surfaces prepared with different Er:YAG laser distance may have different characteristics compared with those prepared with conventional instruments. The aim of this study was to investigate the effect of Er:YAG laser irradiation distance from enamel and dentin surfaces on the shear bond strength of composite with self-etch and etch and rinse bonding systems compared with conventional preparation method. Materials and Methods: Two hundred caries-free human third molars were randomly divided into twenty groups (n = 10). Ten groups were designated for enamel surface (E1-E10) and ten for dentin surface (D1-D10). Er: YAG laser (2940 nm) was used on the E1-E8 (240 mJ, 25 Hz) and D1-D8 (140 mJ, 30 Hz) groups at four different distances of 0.5 (standard), 2, 4 and 11 mm. Control groups (E9, E10, D9 and D10) were ground with medium grit diamond bur. The enamel and dentin specimens were divided into two subgroups that were bonded with either Single Bond or Clearfil SE Bond. Resin composite (Z100) was dispensed on prepared dentin and enamel. The shear bond strengths were tested using a universal testing machine. Data were analyzed by SPSS12 statistical software using three way analysis of variance, Tukey and independent t-test. P < 0.05 was considered as significant. Results: There was a significant difference between enamel and dentin substrates (P < 0.001) and between lased and un-lased groups; the un-lased group had significantly higher bond strength (P < 0.001). Shear bond strength increased significantly with an increase in the laser irradiation distance (P < 0.05) on enamel surfaces (in both bonding agent subgroups) and on dentin surfaces (in the Single Bond subgroup). Conclusion: Laser irradiation decreases shear bond strength. Irradiation distance affects shear bond strength and increasing the distance would decrease the negative effects of laser irradiation. PMID:25540665

Shirani, Farzaneh; Birang, Reza; Malekipour, Mohammad Reza; Hourmehr, Zahra; Kazemi, Shantia

2014-01-01

452

OPTIMUM DESIGN OF ULTRAHIGH STRENGTH NANOLAYERED COMPOSITES  

SciTech Connect

This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). Refinement of the microstructure in metallic multilayers from the micrometer-scale to the nanometer-scale often results in a break down of the classical Hall-Petch model relating strength to the microstructural length scale. The critical length scale at which this behavior breaks down is investigated both experimentally and theoretically. Using transmission electron microscopy and nanoindentation, we evaluated the microstructure and mechanical properties of Cu/Cr, Cu./Ni, and Cu/Nb multilayers that had different shear moduli mismatch between layers and lattice misfit strain between layers. Two-dimensional maps showing layer thickness and grain size ranges over which different deformation mechanisms operate were constructed using dislocation theory. The deformation mechanisms responsible for the breakdown of Hall-Petch behavior are discussed. By correlating the deformation mechanism maps with the experimental data, we show that these maps serve as guidelines for interpreting the scale-dependent deformation mechanisms in multilayers. Atomistic simulation was also used to evaluate the interaction between interfaces and glide dislocations to provide atomic scale insights into the deformation mechanisms.

H. KUNG; ET AL

2000-10-01

453

Simulation studies for surfaces and materials strength  

NASA Technical Reports Server (NTRS)

Computer simulation studies were conducted to investigate materials properties. All the calculations were carried out using atomic level simulation techniques which are based on semiempirical or model functions. During this project, functions with varying degrees of complexity were derived and employed in simulations. Investigations include covalently bonded materials as well as systems involving metal atoms. For small clusters calculated results provided information on various energy- and structure-related properties along with vibrational characteristics. Also, energy barriers for configurational transitions were calculated for selected cases. Simulation calculations for surfaces produced new results in areas related to surface energies, reconstructions and relaxations, surface defects, surface stresses as well as adsorption and nucleation processes. Simulations were also performed on bulk materials. Calculated results provided an atomic level understanding on energetics and structures of point defects, crystal stability, elastic properties, and materials strength for various systems. Calculations involving polymeric materials include studies of polar polymer melts and polymer/solid interfaces. Simulations employing specially developed codes provided significant information about energetics and conformational characteristics of different polymeric chains.

Halicioglu, Timur; Smith, Grant D.

1994-01-01

454

Predicting maximal grip strength using hand circumference.  

PubMed

The objective of this study was to analyze the correlations between anthropometric data and maximal grip strength (MGS) in order to establish a simple model to predict "normal" MGS. Randomized bilateral measurement of MGS was performed on a homogeneous population of 100 subjects. MGS was measured according to a standardized protocol with three dynamometers (Jamar, Myogrip and Martin Vigorimeter) for both dominant and non-dominant sides. Several anthropometric data were also measured: height; weight; hand, wrist and forearm circumference; hand and palm length. Among these data, hand circumference had the strongest correlation with MGS for all three dynamometers and for both hands (0.789 and 0.782 for Jamar; 0.829 and 0.824 for Myogrip; 0.663 and 0.730 for Vigorimeter). In addition, the only anthropometric variable systematically selected by a stepwise multiple linear regression analysis was also hand circumference. Based on this parameter alone, a predictive regression model presented good results (r(2) = 0.624 for Jamar; r(2) = 0.683 for Myogrip and r(2) = 0.473 for Vigorimeter; all adjusted r(2)). Moreover a single equation was predictive of MGS for both men and women and for both non-dominant and dominant hands. "Normal" MGS can be predicted using hand circumference alone. PMID:20708427

Li, Ke; Hewson, David J; Duchêne, Jacques; Hogrel, Jean-Yves

2010-12-01

455

Photophoretic Strength on Chondrules. 2. Experiment  

NASA Astrophysics Data System (ADS)

Photophoretic motion can transport illuminated particles in protoplanetary disks. In a previous paper, we focused on the modeling of steady state photophoretic forces based on the compositions derived from tomography and heat transfer. Here, we present microgravity experiments which deviate significantly from the steady state calculations of the first paper. The experiments on average show a significantly smaller force than predicted with a large variation in absolute photophoretic force and in the direction of motion with respect to the illumination. Time-dependent modeling of photophoretic forces for heat-up and rotation shows that the variations in strength and direction observed can be well explained by the particle reorientation in the limited experiment time of a drop tower experiment. In protoplanetary disks, random rotation subsides due to gas friction on short timescales and the results of our earlier paper hold. Rotation has a significant influence in short duration laboratory studies. Observing particle motion and rotation under the influence of photophoresis can be considered as a basic laboratory analog experiment to Yarkovsky and YORP effects.

Loesche, Christoph; Teiser, Jens; Wurm, Gerhard; Hesse, Alexander; Friedrich, Jon M.; Bischoff, Addi

2014-09-01

456

On Strength at Yield in Condensed Matter  

NASA Astrophysics Data System (ADS)

This paper concerns the lower of a range of thresholds that control the response of condensed matter under loading in compression, from the ambient laboratory state to the point at which the bond strength is overcome and warm dense matter is formed. One oft-used term is yield stress and its variation with the rise time of the loading pulse are considered in this first paper. This threshold shows a correlation between the length scale swept by the rise of the pulse and the defect distribution within the target for a range of materials. Strain rate is also a useful term that reflects the evolution of the stress state within a target but must be defined for a particular volume element containing a particular defect distribution to reflect continuum conditions acting within and thus applies to a defined length scale within a target. This overview of behavior suggests concepts borrowed from rate-independent plasticity have served the community well but that to advance it may be necessary to use viscoplastic concepts in constitutive descriptions for the future.

Bourne, Neil K.

2014-10-01

457

Strength in Cognitive Self-Regulation  

PubMed Central

Failures in self-regulation are predictive of adverse cognitive, academic and vocational outcomes, yet the interplay between cognition and self-regulation failure remains elusive. Two experiments tested the hypothesis that lapses in self-regulation, as predicted by the strength model, can be induced in individuals using cognitive paradigms and whether such failures are related to cognitive performance. In Experiments 1, the stop-signal task (SST) was used to show reduced behavioral inhibition after performance of a cognitively demanding arithmetic task, but only in people with low arithmetic accuracy, when compared with SST performance following a simple discrimination task. Surprisingly, and inconsistently with existing models, subjects rapidly recovered without rest or glucose. In Experiment 2, depletions of both go-signal reaction times and response inhibition were observed when a simple detection task was used as a control. These experiments provide new evidence that cognitive self-regulation processes are influenced by cognitive performance, and subject to improvement and recovery without rest. PMID:23596430

Barutchu, Ayla; Carter, Olivia; Hester, Robert; Levy, Neil

2013-01-01

458

Investigation of factors influencing stalk strength in sorghum  

E-print Network

, and crushing. Stalk diameter was correlated with crushing strength, suggesting a possible need to normalize crushing values to a common stalk diameter. Cloninger et al. (1970) found that crushing strength, rind thickness, and weight of 5. 1 cm sections gave... method for predicting lodging resistance. Twumasi-Afriyie and Hunter (1982) evaluated several methods for determining stalk quality in maize. Their results supported the use of crushing strength, stalk breaking force, and weight of 5, 1 cm stalk...

Richie, William Eldridge

2012-06-07

459

Patterns and Correlates of Muscle Strength Loss in Older Women  

Microsoft Academic Search

Background: The aging process is associated with progressive declines in muscle strength, resulting in functional disability and reduced quality of life. Objective: The purpose of this epidemiological study was to examine the age-related loss of grip strength both cross-sectionally and longitudinally and the risk factors associated with the decline in muscle strength in a large population of community-living older women

Kimberly Y. Z. Forrest; Joseph M. Zmuda; Jane A. Cauley

2007-01-01

460

Functional outcomes of strength training in spastic cerebral palsy  

Microsoft Academic Search

Objective: To determine clinical effectiveness of strength training in children with spastic cerebral palsy.Design: Prospective before and after trial in which subjects participated in a 6-week strength training program. All received before and after isometric strength evaluation of eight muscle groups in both lower extremities with a hand-held dynamometer, 3-D gait analysis at free and fast speeds, administration of the

Diane L. Damiano; Mark F. Abel

1998-01-01

461

Bending strength studies on hot-pressed silicon carbide  

NASA Technical Reports Server (NTRS)

The 4-point bending strength of 4 grades of hot-pressed SiC was determined at different temperatures. With a transgranular mode of fracture the values for bending strength are retained up to high temperatures. For intergranular fracture the decrease of strength is governed by subcritical crack growth. The intergranular fracture is caused by a high content of silicate glassy phase at the grain boundaries of hot-pressed SiC.

Kriegesmann, J.

1984-01-01

462

Ultrahigh strength of dislocation-free Ni3Al nanocubes.  

PubMed

Individual Ni(3) Al nanocubes under pressure are investigated by comparing the compressive strength of both dislocation-free and irradiated Ni(3) Al nanocubes. The results are dicussed in light of the size-dependent and size-independent strength of face-centered cubic (fcc) nanocrystals in the framework of dislocation nucleation at free surfaces. This study sheds more light on the understanding of fundamental deformation mechanisms and size-affected strength in dislocation-free metallic nanocrystals. PMID:22454244

Maaß, Robert; Meza, Lucas; Gan, Bin; Tin, Sammy; Greer, Julia R

2012-06-25

463

Interaction of Adenovirus E1A with the HHV8 Promoter of Latent Genes: E1A Proteins are Able to Activate the HHV-8 LANAp in MV3 Reporter Cells  

PubMed Central

Human herpesvirus 8 (HHV-8) is associated with Kaposi’s sarcoma, body cavity-based lymphoma, and Castleman’s disease. Adenoviral (Ad) E1A proteins regulate the activity of cellular and viral promoters/enhancers and transcription factors and can suppress tumorigenicity of human cancers. As (i) HHV-8 and Ad may co-exist in immunocompromised patients and (ii) E1A might be considered as therapeutic transgene for HHV-8-associated neoplasms we investigated whether the promoter of the latency-associated nuclear antigen (LANAp) controlling expression of vCyclin, vFLIP, and LANA proteins required for latent type infection is regulated by E1A. Transfection experiments in MV3 melanoma cells revealed activation of the LANAp by Ad5 E1A constructs containing an intact N terminus (aa 1-119). In particular, an Ad12 E1A mutant, Spm2, lacking six consecutive alanine residues in the “spacer” region activated the HHV-8 promoter about 15-fold compared to vector controls. In summary, we report the activation of the LANAp by E1A as a novel interaction of E1A with a viral promoter. These data may have relevance for the management of viral infections in immunocompromised patients. A role for E1A as a therapeutic in this context remains to be defined. PMID:19440465

Koehler-Hansner, Karin; Flore, Ornella; Opalka, Bertram; Hengge, Ulrich R

2008-01-01

464

Interaction of Adenovirus E1A with the HHV8 Promoter of Latent Genes: E1A Proteins are Able to Activate the HHV-8 LANAp in MV3 Reporter Cells.  

PubMed

Human herpesvirus 8 (HHV-8) is associated with Kaposi's sarcoma, body cavity-based lymphoma, and Castleman's disease. Adenoviral (Ad) E1A proteins regulate the activity of cellular and viral promoters/enhancers and transcription factors and can suppress tumorigenicity of human cancers. As (i) HHV-8 and Ad may co-exist in immunocompromised patients and (ii) E1A might be considered as therapeutic transgene for HHV-8-associated neoplasms we investigated whether the promoter of the latency-associated nuclear antigen (LANAp) controlling expression of vCyclin, vFLIP, and LANA proteins required for latent type infection is regulated by E1A. Transfection experiments in MV3 melanoma cells revealed activation of the LANAp by Ad5 E1A constructs containing an intact N terminus (aa 1-119). In particular, an Ad12 E1A mutant, Spm2, lacking six consecutive alanine residues in the "spacer" region activated the HHV-8 promoter about 15-fold compared to vector controls. In summary, we report the activation of the LANAp by E1A as a novel interaction of E1A with a viral promoter. These data may have relevance for the management of viral infections in immunocompromised patients. A role for E1A as a therapeutic in this context remains to be defined. PMID:19440465

Koehler-Hansner, Karin; Flore, Ornella; Opalka, Bertram; Hengge, Ulrich R

2008-01-01

465

The Strength of the Metal. Aluminum Oxide Interface  

NASA Technical Reports Server (NTRS)

The strength of the interface between metals and aluminum oxide is an important factor in the successful operation of devices found throughout modern technology. One finds the interface in machine tools, jet engines, and microelectronic integrated circuits. The strength of the interface, however, should be strong or weak depending on the application. The diverse technological demands have led to some general ideas concerning the origin of the interfacial strength, and have stimulated fundamental research on the problem. Present status of our understanding of the source of the strength of the metal - aluminum oxide interface in terms of interatomic bonds are reviewed. Some future directions for research are suggested.

Pepper, S. V.

1984-01-01