bluuebunny/crossref_metadata_2025_split huggingface dataset:
Paclitaxel induces apoptosis via caspase‐3 activation in human osteogenic sarcoma cells (U‐2 OS)
Authors: Lu K.‐H. , Lue K.‐H. , Chou M.‐C. , Chung J.‐G. 
Published: April 2005

AbstractPaclitaxel has been found to exhibit cytotoxic and antitumor activity. There is little information regarding the mechanisms of apoptotic‐inducing effect of paclitaxel on human osteogenic sarcoma U‐2 OS cells. Several key regulatory proteins are involved in the initiation of apoptosis. Caspase‐3 plays a direct role in proteolytic cleavage of cellular proteins responsible for progression to apoptosis. We examined the effect of paclitaxel on the cell cycle arrest and apoptosis in U‐2 OS cells using flow cytometric analysis and Western blotting. We also measured the inhibition of paclitaxel‐induced apoptosis and the caspase‐3 activity by the broad‐spectrum caspase inhibitor z‐VAD‐fmk on U‐2 OS cells. The increased levels of casapse‐3 were also confirmed by cDNA microarray. Our observations were: (1) paclitaxel treatment resulted in G2/M‐cycle arrest in U‐2 OS cells; (2) time and dose dependent apoptosis of U‐2 OS cells was induced by paclitaxel; (3) in U‐2 OS cells, z‐VAD‐fmk blocked the paclitaxel‐induced apoptosis and caspase‐3 activation. These results suggest that paclitaxel‐induced G2/M‐cycle arrest of the G2/M phase and apoptosis via a caspase‐3 pathway in U‐2 OS cells. © 2005 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.
One‐ and two‐strand posterior cruciate ligament reconstructions: Cyclic fatigue testing
Authors: Shearn Jason T. , Grood Edward S. , Noyes Frank R. , Levy Martin S. 
Published: April 2005

AbstractThis study examined how one‐ and two‐strand posterior cruciate ligament (PCL) reconstructions resist the return of posterior translation during repetitive knee cycling. The femoral attachment of the one‐strand graft and the anterior strand of the two‐strand (AD2) grafts were located within the anterior one‐third of the femoral PCL footprint. The second strand was placed within the middle third of the femoral footprint in one of three locations: middle–distal (MD), middle–middle (MM), or middle–proximal (MP). During repetitive knee cycling from 5° to 120° flexion with a 100 N posterior force, the intact knee had less than 1 mm of residual posterior translation after 2048 flexion–extension cycles. Under similar cyclic conditions, the AD2‐MM reconstruction achieved the most cycles before failure; however, this two‐strand configuration failed in less than 700 cycles. The other reconstructions, either one strand or two strand, failed in less than 350 cycles. The surface failure location for 19 of 25 graft strands was within the femoral one‐third of the strand. We concluded that one‐ and two‐strand reconstructions under moderate loading and a range of motion from 5° to 120° flexion have an unacceptably high cyclic failure rate suggesting modifications of the allowable postoperative knee flexion and loading. © 2005 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.
Kinetics of the Reaction of Ethyl Bromomalonate with Thiosulfate
Authors: Broach Wilson J. , Amis Edward S. 
Published: April 2005

The effect of changing the dielectric constant and the effect of changing the ionic strength on the reaction between thiosulfate ion and ethyl bromomalonate have been studied. The rates of the ion-molecule reaction could be accounted for on the basis of the simple second-order mechanism between the dipolar ester molecule and the thiosulfate ion represented by the equation C2H5OOCCHBrCOOC2H5+S2O3==C2H5OOCCH(S2O3)−COOC2H5+Br−and considering the change of ionic strength with extent of reaction to be secondary in importance.
The reactions of thiosulfate ion and ethyl bromomalonate was studied at 0.1°C and at 25°C. The specific reaction rates for this reaction conformed to the prediction of the Amis-Jaffe equations with respect to changing ionic strength and conformed to the Amis equation with respect to changing dielectric constant.
A Proposal for Fundamental Equations of Dynamics of Gases under High Stress (A Proposal for Statistical Mechanical Treatment of Systems Not in Thermal Equilibrium Associated with Transport Phenomena)
Authors: Koga Toyoki 
Published: April 2005

In order to derive the fundamental equations of gas dynamics which are valid for the flow at high shearing stress and low gas pressure, an attempt was made to eliminate the assumption that the state concerned departs only slightly from thermal equilibrium, as we frequently find phenomena which cannot be treated under this assumption.
First, the state of gas in an intermediate volume element was microscopically represented in terms of the quantities of transport. Considering their averages over an intermediate time interval, an attempt was made to find the statistical character of the system. In other words, under the assumption that the macroscopic observation is possible or that the macroscopic law can be established, it was shown that the Boltzmann-Planck method in a new sense is applicable to the present systems. The new distribution function thus derived, f=exp(α+Σβξcξ+ΣΣγξηcξcη+···) (where c denotes the velocity of a particle), should satisfy the Boltzmann-Maxwell equation. This can be shown by means of Kirkwood's verification accepted in some extended meaning.
In solving the B-M equation (hereafter, the B-M equation is the abbreviation of the Boltzmann-Maxwell equation) from this new standpoint, the stress components were taken together with mass density and velocity of mass motion as the independent variables in the zeroth approximation, although usually temperature is taken in place of stress. This method of treatment is analogous to that of Enskog and Chapman, although some important modifications are found in the latter half of the treatment. The fundamental equations of gas dynamics have been derived. Instead of viscosity and thermal conductivity, a new conception arises in the equations. That conception is conductivity of stress.
Millimeter Wave Spectra and Centrifugal Stretching Constants of the Methyl Halides
Authors: Thomas W. J. Orville , Cox J. T. , Gordy Walter 
Published: April 2005

High J transitions of the methyl halides have been measured and have been used to calculate accurate values for the centrifugal distortion constants.
The values obtained for BO, DJJ, and DJK are (in Mc/sec and kc/sec, respectively); CH3·F19, 25 536.11, 59.3, 445; CH3·Cl35, 13 292.86, 18.1, 198; CH3·Br79, 9568.20, 9.9, 128.3; CH3·Br81, 9531.82, 9.7, 127.4; CH3·I127, 7501.30, 6.28, 98.5.
The new DJJ value for CH3·Cl35 is in good agreement with the value of 18.4 kc/sec theoretically predicted by Chang and Dennison.
For all four molecules the DJJ constants were found to be in good agreement with those predicted from Kratzer's formula DJJ=4BO3/ω2,where ω is the vibrational frequency corresponding to the stretching of the carbon halogen bond.
Theory of the Interaction of Hindered Internal Rotation with Over-All Rotations. I. Symmetric Rotors: Methyl Silane
Authors: Kivelson Daniel 
Published: April 2005

An approximate theory of the interactions of hindered internal rotation with over-all rotations of symmetric rotors is given. This treatment considers the interdependence of hindered internal rotation and vibrations and their effect upon the rotational energy levels. The resulting expression for the frequencies of ΔK = 0, ΔJ = 1 transitions is ν=2J[Bv+Fv(m|1−cos3θ|m)+Gv(m|Πz2|m)+LvK(m|Πz|m)],where Bv, Fv, Gv, and Lv are constants independent of the rotational quantum numbers, m represents the basis that diagonalizes the Hamiltonian corresponding to pure internal rotation, πz is the internal angular momentum operator, and θ is the angle of internal rotation. Procedures for evaluating (m|1—cos3θ|m) and (m|πzn|m) in terms of a parameter α are given.
This theory has been applied to the J=0→1 transitions of methyl silane. The parameters Bv, Fv, Gv, and α were obtained empirically and were then used to calculate frequencies. The agreement between observed and calculated values was quite good. Furthermore, the anomalous ordering of the lines observed by Lide and Coles1 is explained by these calculations. Assuming a cosine potential, the barrier height V0 is proportional to the parameter α. The value of V0 was set at 558 cm-1±17 cm-1. The constant Bv, which is the rotational constant in the ground torsional state for the limiting case of V0=0, is 10985.79 Mc/sec and 9636.50 Mc/sec for CH3SiH3 and CH3SiD3, respectively.
Redetermination of the Crystal Structure of Lithium Sulfate Monohydrate Li2SO4·H2O
Authors: Larson Allen C. , Helmholz Lindsay 
Published: April 2005

The crystal structure of lithium sulfate monohydrate has been reinvestigated in order to determine the position of the hydrogen bonds and to check on the asymmetry of the sulfate group in this substance suggested by the earlier work of Zeigler.
A disposition of the hydrogen bonds in agreement with the proton magnetic resonance results has been found and the sulfate group has the configuration of a regular tetrahedron within the limits of error of our measurements. Our results are in agreement with Zeigler in most essentials.
Second Virial Coefficients of Gases Obeying a Modified Buckingham (Exp—Six) Potential
Authors: Rice William E. , Hirschfelder Joseph O. 
Published: April 2005

The second virial coefficient has been calculated for gases obeying a modified Buckingham potential, (Exp-Six), [open phi](r)=ε1−6/α[6αeα(1−r/rm)−(rmr)6].The results are tabulated over the temperature range kT / ε from 0.40 to 400, and for seven values of the parameter α, from 12 to 15. The treatment was entirely classical, and no corrections for quantum effects were made.
A separate paper will present the evaluation of the parameters for specific substances and applications of the results, together with applications of the calculated transport properties given in the preceding paper.
Occurrence of Natural p — n Junctions in Lead Selenide
Authors: Goldberg Arthur E. , Mitchell George R. 
Published: April 2005

Single crystals of PbSe were grown from melts in sealed quartz tubes. Except for a very narrow range of initial melt compositions, stoichiometric excesses of Pb or Se in the melt resulted in crystals that were wholly n or p type, respectively. Initial composition within the critical range yielded crystals showing both p and n regions.
The electrical resistivities were related to crystal compositions permitting the construction of the Pb-Se phase diagram in a narrow region about the compound PbSe. The invariant melting point for the system falls in the Se-rich region. This precludes the possibility of growing a crystal from a melt which is of stoichiometric composition throughout.
The Effect of Compression and of Hydrostatic Pressure on the Diffusion Anisotropy in Zinc
Authors: Liu T. , Drickamer H. G. 
Published: April 2005

Measurements have been made on the rate of self-diffusion in single crystals of zinc along the directions both parallel and perpendicular to the C axis. The effects of compression by an applied force and hydrostatic pressure up to 10 000 atmospheres on the rate of diffusion were studied. The self-diffusion coefficients of polycrystalline zinc were also measured under both atmospheric pressure and compression.
The rate of self-diffusion in single crystals of zinc was found always to be larger in the direction parallel to the C axis, while the enthalpy of activation was found always to be smaller in this direction. Both compression and hydrostatic pressure tend to reduce the rate of self-diffusion, the greater effect being observed in the direction parallel to the C axis. Compression perpendicular to the direction of diffusion gave essentially the same effect as compression in the direction of diffusion. The enthalpy of activation was found to be increased 30 percent by the application of a pressure of 8000 atmospheres and to be decreased slightly by compression. The anisotropy in the rate of diffusion was found to decrease with increased hydrostatic pressure. The self-diffusion coefficients of polycrystalline zinc were found to be intermediate between the values observed in the two directions (parallel and perpendicular to the C axis) in single crystals and to be closer in magnitude to the values observed in the direction perpendicular to the C axis.
The Thermal Conductivity of Organic Vapors. The Relationship between Thermal Conductivity and Viscosity, and the Significance of the Eucken Factor
Authors: Vines R. G. , Bennett L. A. 
Published: April 2005

The thermal conductivities of thirty-one polar and nonpolar organic vapors have been determined at pressures up to one atmosphere, over a temperature range from 40 to 160°C. The relation between thermal conductivity and viscosity is discussed in terms of the expression: K0MηCv0=f=ftransCvtrans+fintCvintCv0where, following a suggestion by Eucken, the ratio f is divided into separate components ftrans and fint, corresponding to the different rates of transfer of translational and ``internal'' (vibrational and rotational) energies.
Experimental values of f are not in accord with Eucken's original assumption that fint=1. For nonpolar vapors fint increases towards a high-temperature limit which is close to the theoretical value of 1.3. For polar vapors ftrans appears to be less than the theoretical value of 2.5, the decrease depending on the polar character of the molecule. These results are discussed with reference to energy exchanges occurring during collisions between complex molecules.
Vibrational Intensities in Diatomic Infrared Transitions. The Vibrational Matrix Elements for CO
Authors: Herman Robert C. , Shuler Kurt E. 
Published: April 2005

Second-order perturbation theory has been employed to obtain general formulas for the (rotationless) vibrational matrix elements of diatomic molecules in infrared transitions. The mechanical and electrical anharmonicities have been taken into account by expanding the potential function in a power series through quartic terms and the electric dipole moment through cubic terms in the internuclear separation. The formulas obtained in this manner are shown to be quite accurate for the fundamental and the first two overtones.
These expressions were then employed to evaluate the vibrational matrix elements for CO (1Σ+) up to v′=4 using the experimental integrated absorption coefficients as auxiliary data for the determination of the electric dipole moment expansion coefficients. A comparison of the vibrational matrix elements for CO involving the use of perturbed harmonic oscillator wave functions with those obtained using Morse wave functions with both linear and quadratic expansion of the electric dipole moment indicates that the Morse treatment is applicable through higher vibrational quantum numbers and higher transitions than the perturbation treatment. The comparison furthermore shows that the simple Morse expression with a linear expansion of the electric dipole moment yields vibrational matrix elements which would appear to be sufficiently accurate for many purposes.
The anharmonic oscillator wave functions obtained would also prove useful in the evaluation of vibrational matrix elements in electronic transitions if the array for the harmonic oscillator overlap integrals were extended through higher vibrational quantum numbers.
Generalization of the Radial Dilution Square Law in Ultracentrifugation
Authors: Trautman Rodes , Schumaker Verne 
Published: April 2005

The classical square law of radial dilution, which relates the concentration of a single component to the boundary position in the ultracentrifuge cell, has been examined and found to be valid for a single component as well as for a multicomponent system even though the sedimentation rates are dependent on concentration.
The square law has been generalized to give corrected concentrations without the necessity of determining boundary positions explicitly. A system of warped coordinates has been introduced to simplify this application of the square law. A special template and its use is described which incorporates both the warped coordinates and the baseline and which enables very rapid reading of areas from routine ultracentrifugal runs.
Scattering of High-Velocity Neutral Particles. III. Argon-Argon
Authors: Amdur I. , Mason E. A. 
Published: April 2005

Total collision cross sections have been measured for argon atoms, with energies between 700 and 2100 ev, scattered in room temperature argon. Results obtained with two detectors of different geometric aperture are shown to be in accord when allowance is made for beam shape, intensity distribution, and scattering to a detector which is narrower than the beam, in accordance with procedures previously used for helium scattered in helium.
Potential energy information derived from the cross sections may be represented by V(r)=1.36×10−9/r8.33 ergsfor values of r between 2.18A and 2.69A, and appears to be consistent with that derived from measurements of gaseous compressibility, viscosity, and crystal properties.
Reaction of Cyclohexane with Mercury-6(3P1) Atoms
Authors: Beck P. W. , Kniebes D. V. , Gunning H. E. 
Published: April 2005

An investigation has been made of the mercury-6(3P1)-photosensitized decomposition of cyclohexane at 29.30±0.01°C, under static conditions. The products of the reaction are hydrogen, bicyclohexyl, and cyclohexene, in order of decreasing importance. The mean quantum yields of cyclohexane disappearance, hydrogen formation, and cyclohexene formation were found to increase slightly with increasing substrate pressure; at 90-mm cyclohexane pressure, the values are 0.83, 0.43, and 0.03, respectively. Extrapolation to initial conditions of data on the variation of mean quantum yield with time at constant substrate pressure gave 0.55 for the initial quantum yield of hydrogen formation, and 0.17 for cyclohexene formation, independent of substrate pressure. From the foregoing initial quantum yield data, taken in conjunction with the stoichiometry of the reaction, a value of 0.93 was obtained for the initial quantum yield of cyclohexane consumption.
Absence of hexane, dodecanes, n-hexylcyclohexane, and low molecular weights products was taken as evidence of the stability of the cyclohexane ring during reaction.
The results of the investigation can be adequately accounted for by the following simple mechanism:(1) cyclo C6H12+Hg 6(3P1)→cyclo C6H11+H+Hg 6(1S0),(2) H+cyclo C6H12→H2+cyclo C6H11,(3) 2 cyclo C6H11→cyclo C6H10+cyclo C6H12,(4) 2 cyclo C6H11→bicyclo C12H22,(5) H+cyclo C6H10→cyclo C6H11.
Steps (1) to (4) describe the reaction under initial conditions.
From the initial quantum yield data the ratio k4/k3, the ratio of the rates of recombination to disproportionation for cyclohexyl radicals, was evaluated at 2.2. In short, recombination is approximately twice as fast as disproportionation for cyclohexyl radicals.
Hybridization and Ionic Character in the Hydrogen Chloride Molecule
Authors: Schatz Paul N. 
Published: April 2005

Hybridization in the HCl molecule has been studied in terms of an spd hybrid valence bond function including an ionic term (H+–Cl-). The results indicate that the quadrupole coupling constant for gaseous HCl (not known experimentally) may be of the order of 100 percent larger than the value reported for the solid. It is found that the quadrupole coupling constant depends principally on the amount of ionic character and does not distinguish among various possible hybridizations.
The sign of the dipole moment is discussed briefly.
Reduction of SrO by Methane
Authors: Moore George E. , Allison H. W. , Wolfstirn K. B. 
Published: April 2005

The reduction of SrO supported on purified platinum or nickel filaments was investigated over the range 1050 to 1700°K. Reduction is rapid, and at least part occurs in two major steps: (1) the methane dissociates, depositing carbon in the oxide, which (2) then reacts with SrO to give Sr and CO.
When SrO is supported on platinum filaments a major part of the Sr enters the platinum. This is far less pronounced in nickel supports. Possible significance for the oxide cathode is discussed. Calculations indicate that SrC2 may also be formed.
The Determination of the Potential Constants of SO2 from Centrifugal Distortion Effects
Authors: Kivelson Daniel 
Published: April 2005

The microwave spectrum of SO2 was reanalyzed with particular emphasis upon the effect of centrifugal distortion. It was possible to fit the rotational spectrum to within a mean deviation of ±0.23 Mc using the energy expression given by Kivelson and Wilson. The rotational constants so determined are a=60778.79 Mc, b=10318.10 Mc, and c=8799.96 Mc. The four distortion constants could not be uniquely determined directly from the rotational spectrum.
The sets of potential constants determined by Wilson and Polo were used to calculate distortion constants and these in turn used to calculate frequency shifts due to centrifugal distortion. These shifts are critically dependent upon the set of potential constants used. By choosing a set of potential constants compatible with the infrared spectrum which also yield distortion frequency shifts in accord with those obtained from a direct analysis of the rotational spectrum, a very sensitive determination of the potential constants may be made. The resulting force constants are: fd=10.006×105 dyne cm—1; fα/d02=0.7933×105 dyne cm—1; fdd=0.0236×105 dyne cm—; fdα/d0=0.189 dyne cm—.
The Photolysis of Ammonia at 1849A in a Flow System
Authors: McDonald C. C. , Kahn A. , Gunning H. E. 
Published: April 2005

An investigation has been made of the photolysis of ammonia at 1849A in a flow system at room temperature. The products of the reaction were found to be hydrazine, hydrogen, and nitrogen. The rate of decomposition of ammonia was independent of the linear flow rate but depended upon the ammonia pressure in the reaction zone. The fraction of ammonia decomposed which was recovered as hydrazine, while independent of ammonia pressure, increased markedly with increasing linear flow rate from zero in the static system to 0.84 at a linear flow rate of 1750 cm/sec.
It was found that the quantum yield of ammonia consumption under flow conditions was consistently higher by a factor of approximately two than for the static conditions at the same pressures.
A separate system was used to determine the extinction coefficient of ammonia at 1849A over the pressure range of the experiments. The value obtained was 1.21×103 liters-mole-1—cm—1.
A mechanism has been proposed which is in qualitative agreement with the observed facts.
Semiempirical Potential Energy Functions. I. The H2 and H2+ Diatomic Molecules
Authors: Frost Arthur A. , Musulin Boris 
Published: April 2005

After setting up certain theoretical criteria for a semiempirical potential energy function, two such functions for H2+ and H2 are constructed, the simplest of which has the form V=e-aR(e2R−b),where V is the potential energy with its zero corresponding to infinite separation. R is the internuclear distance, e the electronic charge, and a and b parameters. This function is used to correlate the experimental quantities: dissociation energy, equilibrium internuclear distance, force constant, third and fourth derivatives of V with respect to R, united atom energy, and critical distance.
A more complicated function is also presented which with one molecular parameter fixed by the dissociation energy is capable of then predicting internuclear distance and force constant.