bluuebunny/crossref_metadata_2025 huggingface dataset:
Resource Letter BE-1 on Biomedical Engineering
Authors: Johnson Curtis C.
Published: August 2005

Prepared at the request of the AAPT Committee on Resource Letters. This is one of a series of Resource Letters on various topics, intended to guide college physicists to literature and other teaching aids that may help them improve course content in specified fields of physics. No Resource Letter is meant to be exhaustive and complete. In time, there may be more than one letter on some of the main subjects of interest. Comments and suggestions concerning the content and arrangement of letters as well as suggestions for future topics will be welcomed and should be addressed to Professor Joel E. Gordon, Chairman, AAPT Committee on Resource Letters, Department of Physics, Amherst College, Amherst, Mass. 01002.

Notation: The letter E after an item indicates elementary level, useful principally for high school and introductory college use; the letter I indicates intermediate (junior, senior) level; and the letter A indicates advanced material, principally suited for senior, graduate level. An asterisk (*) indicates items particularly recommended for introductory study.
Science for the Nonscience Major—Problem and Partial Prescription
Authors: Priestley Herbert
Published: August 2005

After a brief review of the need for some experience in science for the nonscience major and a listing of what appear to be desirable objectives for that experience, details are given of a course which has been offered for the past four years.
The Electric Dipole Moment of a Moving Magnetic Dipole
Authors: Fisher George P.
Published: August 2005

The fact that a magnetic dipole μ moving with velocity βc has an electric dipole moment p = β×μ/c has made periodic appearance in the literature but the importance of this fact and its general utility have not been given sufficient expression. It is the purpose of this paper to show how to derive the equation p=β×/c and then to use it for a simple description of the atomic spin-orbit interaction.
Science Education: A Case for Astronomy
Authors: Wentzel Donat G.
Published: August 2005

An astronomy course can demonstrate to the nonscientist that science is a human endeavor, involving social judgments and philosophical implications as well as established facts.
Transverse Vibrations of Linear and Layer Lattices
Authors: Kothari L. S. , Ghatak A. K. , Bala Shashi
Published: August 2005

In this communication we have shown that in the harmonic approximation, the transverse vibrations of a one-dimensional linear lattice, as also of a two-dimensional lattice (with particle displacements normal to the plane), can only be explained by introducing angular forces. The study on vibrations of a two-dimensional hexagonal lattice has been applied to the graphite lattice, and the calculated values of the specific heat have been compared with the experimental data.
West European Scientific Museums: A Survey
Authors: Albergotti J. C.
Published: August 2005

A descriptive list of some of the scientific museums of interest to physicists in France, Great Britain, Italy, The Netherlands, Switzerland, and West Germany.
A Wavepacket Generator for Demonstrating the Complementarity Rule
Authors: Cooke James H. , Bates Kenneth N.
Published: August 2005

We describe an inexpensive demonstrator which produces electrical wavepackets of variable length. The packets contain from one to sixteen 1-MHz waves. Students may make a Fourier analysis of the packets with ordinary AM radios. They will discover dramatically different spectra, confirming the complementarity rule between packet length and bandwidth, ΔxΔk≳1.
Specific Heat and Debye-Waller (Lamb-Mössbauer) Factor for a Finite One-Dimensional Lattice
Authors: Khatri D. S. , Kothari L. S.
Published: August 2005

It is shown that the Debye-Waller factor (or Lamb-Mössbauer factor) for a finite one-dimensional lattice is nonzero (it is zero for an infinite one-dimensional lattice) and experimental situations can exist when elastic neutron scattering or recoilless emission or absorption of γ rays may be observed in polymers. Specific heat of finite linear lattices is also worked out. It is found that the conditions under which one may replace the sum over lattice modes by an integration without introducing much error in the calculation of the Debye-Waller factor are entirely different from similar conditions in the case of specific heat.
New Instruction with an Old Interferometer
Authors: Abbott Hilton , Johnson Fred T. , Licata Raymond , Oliver Philip
Published: August 2005

This paper describes how a particular implementation of Fourier spectroscopy can be used as an educational instrument to (1) demonstrate graphically the Fourier transform nature of Fraunhofer diffraction and (2) introduce basic concepts of coherent optics at a simple and economic level.
Simple Computer Programs in Introductory Geometrical Optics
Authors: Merrill John R.
Published: August 2005

This note reports some applications of time-shared computers to introductory geometrical optics. Three programs are introduced which are written in the Dartmouth College form of the language BASIC. The first program illustrates simple thin lens theory calculations. The second program traces rays through a thick lens system by using Snell's law at every interface. The third program traces rays through a medium in which the index of refraction is a continuous function of position. The third program illustrates mirage and looming phenomena. All the programs have been used in second-semester physics courses; often the students write better forms of the programs.
A Variable Coeficient of Restitution Experiment on a Linear Air Track
Authors: Gruebel R. , Dennis J. , Choate L.
Published: August 2005

A system consisting of two pendula attached to an air cart is mathematically analyzed, and the coefficient of restitution is shown to pass through a deep minimum. The solution to the small angle equation of motion is transcendental and provides an exercise in graphical methods for the beginning mechanics student.
Theory for a Unidirectional Interferometric Test of Special Relativity
Authors: Weinberger H. , Mossel M.
Published: August 2005

An early criticism of the experimental background of special relativity theory was that the Michelson-Morley experiment was bidirectional in the moving frame. This experiment did not require that the velocity of light is constant in all Galilean frames, but only that the average to-and-fro velocities are constant. These objections were removed with the experimental verification of the time dilation effect predicted by relativity theory. It is coneptually simple to devise a unidirectional ether drift experiment based on a measure of fringe shifts. The experiment could not be performed in Michelson's time because of the large coherence lengths required for the observation of the fringe shifts. For an interference arrangement similar to that used to produce Young's fringes, a coherence length greater than a meter is required in order to observe a displacement of 0.01 fringes. Such coherence lengths are available today from continuous wave lasers.
A Course in Biophysics: An Integration of Physics, Chemistry, and Biology
Authors: Giancoli Douglas C.
Published: August 2005

An interdisciplinary course for advanced undergraduates in the physical and biological sciences is described. The goal is to understand a living cell from the most basic standpoint possible. Starting at the subatomic level, the basic knowledge of twentieth-century physics is utilized to understand the structure and function of atoms, simple molecules, and eventually macromolecules, cellular organelles, and the many processes occurring within a cell. The ideas of physics, chemistry, and molecular biology are all essential to the course, which leads to a unified view of the sciences.
Fourier Analysis and Spatial Filtering
Authors: Brown Judith C.
Published: August 2005

The theory of Fourier analysis and spatial filtering is developed in a form suitable for inclusion in the undergraduate curriculum. Applications to Babinet's principle and to the Rayleigh criterion of resolution are discussed. A number of useful laboratory experiments are described.
Coherent Scattering of Sound Waves by Isotopic Impurities in a Crystal Lattice
Authors: Allen Kenneth R. , Powell John D.
Published: August 2005

An infinite crystal containing a single plane of isotopic impurities is considered, and by using the Green's function technique, the amplitudes of sound waves scattered by the plane are calculated in the first Born approximation. The scattered waves are shown to be plane waves reflected and transmitted at well-defined angles. Similarities and differences with the corresponding electromagnetic case are noted and discussed.
Second-Order Pressure Distribution in an Acoustic Normal Mode in a Rectangular Cavity
Authors: Ingard Uno , Galehouse Daniel C.
Published: August 2005

The second-order (time independent) pressure distribution in a standing sound wave in a rectangular cavity is shown to produce a static deformation of the surface of a liquid that partially fills the cavity. Projection of this surface deformation provides a simple means of visualization of acoustic normal modes in a cavity.
Self-Rectification in Diodes and the Second Law of Thermodynamics
Authors: McFee Richard
Published: August 2005

Does a diode rectify its own thermally induced voltage fluctuations? If so, it will act like a miniature battery in violation of the second law of thermodynamics. Although early theoretical computations indicated that self-rectification could occur, no experimental confirmation followed. In 1960 Van Kampen published an analysis which demonstrated that the self-rectification voltage should be zero. His analysis is reviewed here, where it is found to imply another closely related effect, not self-rectification, which could be in conflict with the second law. This hypothetical effect arises from the quantization of charge and can in theory be seen at very low temperatures (50 millidegrees) and small diode capacitance (0.01 pF).
The Epistemological Basis of Einstein's, Podolsky's, and Rosen's Objection to Quantum Theory
Authors: Reisler Donald L.
Published: August 2005

The Einstein-Podolsky-Rosen paradox continues to be the center of great controversey and illumination within quantum theory. In this paper we examine Einstein's scientific epistemology in order to discover the basis for his objections to quantum theory. Then we discuss the consequences and implications of this for the EPR paradox and the quantum mechanical method of state representation.
Satellite Orbit Paradox: A General View
Authors: Blitzer Leon
Published: August 2005

The satellite orbit paradox is examined from the viewpoint of energy considerations, with no restrictions as to the physical character or direction of the perturbing force. Application is made to three diverse phenomena, in which the paradox is the common link: (i) the increase in speed of a satellite subject to atmospheric drag, (ii) the librational motion of a 24-h equatorial satellite, and (iii) the secular increase in the length of the month.
Relativistic Thermodynamics
Authors: Callen Herbert , Horwitz Gerald
Published: August 2005

The generalization of thermodynamics to special relativity is discussed, with emphasis on the thermodynamic rather than the relativistic aspects of the problem. We demonstrate and stress the fundamental role of the enthalpy in confined systems. We agree with the generally accepted Ott conclusion that heat flux appears larger to a moving observer (but other results may be equivalent if interpreted appropriately). The transformation law of the temperature is subject to choice. The simplest relativistic generalization of thermodynamics, which we describe, leads naturally to the choice of a Lorentz invariant temperature. There are also compelling heuristic reasons for adopting this definition, which we strongly favor. However it has been conventional to couple this generalization of thermodynamics with a further generalization, adopting the center-of-mass momentum as an independent thermodynamic variable. This has led to other choices of transformation laws of heat and temperature. We believe that this second generalization is unnatural from the thermodynamic point of view, despite its apparent relativistic elegance. The center-of-mass momentum is not an appropriate thermodynamic variable. The number of microstates of a system is not dependent on its state of motion relative to an observer, so that the implied dependence of entropy on momentum is a misleading formalism.
Three Experiments in Friction for the Introductory Laboratory
Authors: Fox Geoffrey T.
Published: August 2005

One experiment involving sliding friction and two experiments concerned with fluid friction are described. All three require an absolute minimum of equipment and yet are very useful for the simulation of real physics research. Because friction is given little attention in most introductory textbooks the experiments can be in the nature of discoveries rather than verifications.
Time-of-Flight Experiments in Molecular Motion and Electron-Atom Collision Kinematics
Authors: Donnelly Denis P. , Pearl John C. , Zorn Jens C.
Published: August 2005

A set of experiments for an undergraduate laboratory which demonstrate the relationship between velocity, mass, and temperature in a gas is described. The experimental method involves time-of-flight measurements on atoms excited to metastable states by electron impact. Effects resulting from recoil in the electron-atom collision can also be observed. A suitable apparatus for conducting the experiments is described.
Local Observables in Quantum Theory
Authors: Hestenes David , Gürtler Richard
Published: August 2005

The Pauli theory of electrons is formulated in the language of multivector calculus. The advantages of this approach are demonstrated in an analysis of local observables. Planck's constant is shown to enter the theory only through the magnitude of the spin. Further, it is shown that, when obtained as a limiting case of the Pauli theory, the Schrödinger theory describes a particle with constant local spin. An important consequence of this result is the realization that the usual interpretations of the Dirac and Schrödinger theories are mutually inconsistent in certain details.
The First Law of Elasticity
Authors: Girill T. R.
Published: August 2005

During the decades immediately after its discovery, the Boyle-Mariotte gas law was formulated in terms of pneumatic “springs,” subsumed by Hooke under his own stress-strain relation, and generally regarded as a law of elasticity. The subsequent historical development of Boyle's principle, and that of the concept of elasticity with which it is no longer associated, provide thought-provoking test cases for Thomas Kuhn's notions of paradigm and puzzle solving in physics.
Superradiance in Radiatively Coupled Tuning Forks
Authors: Lama W. L. , Jodoin R. , Mandel L.
Published: August 2005

The effect of superradiance in the decay of coupled harmonic oscillators has been demonstrated in some simple experiments with two tuning forks and resonators. The results show the theoretically predicted shortening and lengthening of the decay times according as the oscillators are initially in phase or in antiphase. When the initial phase difference is π/2, the decay times appear to be unaffected by the coupling of the oscillators.
An Electrical Analog Computer for Poets
Authors: Bruels Mark C.
Published: August 2005

The question of whether to present the non-physics major with a direct current experiment beyond Ohms law and series and parallel laws has a pleasant solution. Construction of an analog computer for multiplication and division from common rheostats and student-assembled voltmeters leads to a firm grasp of basic series and parallel laws in d.c. circuits.
Green Functions and Perturbation Theory
Authors: Silvert William
Published: August 2005

We show a pedagogically useful way of deriving both stationary and time-dependent perturbation theory from the field-theoretical Hartree-Fock approximation. The calculation clearly shows how the contributions of real and virtual processes differ.
Astronomically Determined Dates and Alignments
Authors: Winkler Louis
Published: August 2005

This is a tutorial article concerned with problems related to dates and, geometrical alignments determined from astronomical considerations. The mathematical problems often arise in connection with attempts to specifiy days of the year in the past or in connection with ancient edifices. In this way the solutions are of interest to anthropologists, archeologists, art historians, folklorists, historians, and astronomy enthusiasts. While the methods of solution presented are general, specific problems are also employed for illustrative purposes. Some problems involve the famous ancient edifices of Abu Simbel, Cheops' Pyramid, and Stonehenge, and bright celestial objects such as the Sun, Sirius, and the Pleiades. Solutions depend on a knowledge of spherical trigonometry and basic astronomy, and often involve the phenomenon of the precession of the Earth's spin axis. Effects of precession are described geometrically and algebraically.
Introductory Quantum Mechanics with the Computer
Authors: Merrill John R.
Published: August 2005

This paper presents a way to use a computer in the teaching of introductory, stationary state, Schrödinger quantum mechanics. The method is based upon an easily explained computer method; a 20-line program in BASIC is presented to implement the strategy. Not only is this numerical technique completely general for all one-dimensional and all spherically symmetric, three-dimensional problems, but also it allows the student to be introduced to topics of interest such as asymptotic solutions. Several examples of the use of the computer technique are presented.
Electron Energy Eigenvalues in an Infinite One-Dimensional Type-AB Alloy
Authors: Wu Chu Tzu , Schwensfeir R. J.
Published: August 2005

The transfer-matrix method is used to derive the characteristic equation for electron energy eigenvalues in a generalized infinite one-dimensional binary alloy. The alloy is divided into unit cells and subcells so that the method used is independent of the shape of the potential barriers. Application of the technique to a type-AB one-dimensional alloy represented by an infinite chain of two kinds of square potential barriers gives the energy eigenvalue equation for this case explicitly and for the first time. The formalism is also shown to give the Kronig-Penney result for a chain of identical square potentials.
Emission of Radio-Frequency Waves from Plasmas
Authors: Bekefi G. , Brown Sanborn C.
Published: August 2005

Observations of the radio-frequency emission from extraterrestrial plasmas and plasmas produced in the laboratory are described, and various attempts at interpretation of the results are reviewed. Estimates are made of the probable loss of radiant energy from plasmas in proposed thermonuclear reactors.
Vibrations of a Lattice Including Defects: Laboratory Demonstrations Using Electrical Analogs
Authors: Scott P. L.
Published: August 2005

Simple inexpensive electrical analogs are described that illustrate the qualitative and quantitative behavior of wave motion on a one-dimensional monatomic lattice, a diatomic lattice, and on a lattice containing a defect.
Thermodynamic Description of Materials at High Pressures
Authors: Davis R. O.
Published: August 2005

A technique is presented for deriving the caloric equation of state for materials at high pressures. An incomplete equation of state, giving pressure as a function of density and energy, is used as input to a partial differential equation for entropy. The incomplete equation of state is usually inferred from shock-wave experiments. The entropy equation can be solved, provided sufficient initial data are available. The technique is illustrated by two examples, a polytropic gas and a Mie-Gruneisen-type material.
An Electrostatic Oscillator Experiment
Authors: Martin D. H. , Longbrake R. L.
Published: August 2005

An experiment involving a conducting sphere that oscillates between two electrodes is described. Theory is presented that predicts a linear relationship between frequency and applied voltage for the system, regardless of electrode configuration. Data taken for several geometries is in good agreement with this theory. Some properties of the oscillator system, including its desirable characteristics as a high voltage voltmeter, are discussed.
The Hamiltonian of Quantum Electronics
Authors: Savolainen J. , Stenholm S.
Published: August 2005

This paper discusses the quantization of electromagnetic fields interacting with nonrelativistic atoms and molecules in the dipole approximation. Quantizing the field variables D and H and taking the interaction density −ε0−1P·D, we obtain a quantum theory corresponding to classical electrodynamics with no free currents and the induced dipole moments as the only sources of the radiation field. The resulting equations are found to agree with those Power and Zienau obtained from causality requirements. A comparison with the conventional approach is given.
Particle Tracks in Cellulose Nitrate
Authors: Pilcher V. E. , Jones C. C. , Ellmers G. R.
Published: August 2005

A simple procedure for observing alpha particle tracks in cellulose nitrate is described with emphasis on qualitative understanding of the underlying principles. The technique is shown to be feasible for use in the undergraduate nuclear laboratory as well as offering a variety of possibilities for independent student investigations at very low cost. The results of a Rutherford scattering experiment are included as an example of the type of measurements for which this detector can be used.
The Magnetic Field as a Mechanism to Preserve Relativistic Momentum
Authors: Dewan Edmond M.
Published: August 2005

A thought-experimental approach is given to the definition of the magnetic field as a force arising from the need to conserve relativistic momentum. Mechanical and electromagnetic analogies are compared to illustrate the mechanisms of momentum transfer from field or stress energy to kinetic energy of a particle.
Even and Odd Spectra of One-Dimensional Symmetrical Potential. I. Schrödinger Theory
Authors: Ronveaux André
Published: August 2005

The discrete spectrum of a one-dimensional symmetrical potential is studied within the framework of the Schrödinger theory using the variable phase approach. Separate Riccati equations characterizing the even and odd spectra are given, and the two lower states are defined by transcendental inequalities. Possible extension to a nonsymmetrical potential is also indicated and some numerical results are checked for a solvable potential of infinite range.
A Simple Demonstration of Flux Quantization in Superconductors
Authors: Vandervorst S. , Hermans F. , Lambert M. H.
Published: August 2005

An indium film containing ̃2×106 holes is used, together with a standard magnetometer, to demonstrate the quantization of flux in superconductors.
Uncertainty Relations for Nonsimultaneous Measurements
Authors: Levy-Leblond Jean-Marc
Published: August 2005

The usual Heisenberg uncertainty relations are generalized to the case of nonsimultaneous measurements of position and momentum. The product of the corresponding uncertainties is bounded from below by a quantity depending on the dynamics of the system (the potential), and which may be lower than ħ/2 and even vanish. The case of two successive measurements of momentum and position is also treated, and one recovers the standard phenomenon of spreading of the wave packet. Whereas the case of an arbitrary potential can only be treated to lowest orders in the lime delay, a complete solution is given for the harmonic oscillator.
A Remark on Maxwell's Displacement Current
Authors: Mello P. A.
Published: August 2005

One usually derives Ampere's law by taking the curl of the magnetic field given by the law of Biot and Savartfor a volume distribution of currents J. In the derivation, one drops a term that contains ∇ · J, in order to treat stationary processes. It is shown that if that term is kept one gets, for ∇ × H, a term which is the usual conduction current J plus a second term similar to Maxwell's displacement current, present even outside the current distribution J. That extra term is δD0/δt, where D0 = ε0E0 and E0 is the instantaneous Coulomb field produced by the charges in question.
A Useful Device for Illustrating the Lorentz Transformations
Authors: Cortini Giulio
Published: August 2005

A graphical representation is proposed as a teaching device which can be useful in order to obtain a good intuitive grasp of the physical meaning of the Lorentz transformations. The connection between the time dilation and the desynchronization of clocks is particularly discussed.
Note on Current Conservation, Charge, and Flux Integrals
Authors: Deser S.
Published: August 2005

The distinctions between the notions of conserved current, conserved charge, and flux integral forms for charge are illustrated.
A Special Class of Ideal Quantum Gases
Authors: Huang Y. K.
Published: August 2005

This essay is motivated to add a useful note to the contemporary literature of ideal gases. For brevity, a new description is given for a special class of ideal quantum gases (the “qsuper ideal gases”) which are characterized here by two compact equations of state. Within such a framework all fundamental properties of these gases are readily expressed in terms of two constants known as the state indices. In order to test our results of deduction, six typical examples are given with comparable numerical values. While all the examples must otherwise have resort to statistical calculations, our evaluation for them turns out to be straightforward as well as heuristic.
Poincaré's Rendiconti Paper on Relativity. Part III
Authors: Schwartz H. M.
Published: August 2005

This is the concluding part of a modernized rendition of Poincaré's Rendiconti paper on relativity, of which the first two parts appeared in the November 1971 and June 1972 issues of this Journal. It covers the last section of that paper, in which Poincaré develops in masterful, even if incomplete, fashion, a generalization of Newtonian gravitational theory, involving retarded action-at-a-distance interaction that is covariant under the Lorentz group. As the first such attempt it is of obvious historical significance. In addition, just as the first two parts, so this part, too, contains material of independent interest to the historian of the genesis of special relativity.
Image Location and Magnification in Holography
Authors: Givens M. Parker
Published: August 2005

A method is presented for determining the location and magnification of images formed by holographic reconstruction. The method is based upon the similarity between a hologram and a zone plate. An undergraduate student familiar with introductory optics should be able to understand the method presented.
Weighing in the Physics Laboratory: A Thorough Study of a Simple Measurement
Authors: Meyer Stuart L.
Published: August 2005

A simple weighing experiment was performed by beginning freshman students as a first introduction to measurement. Harking back to the historical antecedents of weighing, coins were weighed using two balances of different precisions. The analysis proceeded to increasing levels of sophistication to elucidate various concepts involving distributions, resolutions, standard deviation, standard deviation of a mean, and confidence in the existence of an observed effect.
Resource Letter TQE-1: Tests of Quantum Electrodynamics
Authors: Sternheim Morton M.
Published: August 2005

Prepared at the request of the AAPT Committee on Resource Letters. This is one of a series of Resource Letters on different topics, intended to guide college physicists to some of the literature and other teaching aids that may help them improve course contents in specified fields of physics. No Resource Letter is meant to be exhaustive and complete; in time there may be more than one letter on some of the main subjects of interest. Comments and suggestions concerning the content and arrangement of letters as well as suggestions for future topics will be welcomed. Please send such communications to Professor Arthur Quinton, Chairman, Resource Letter Committee, Department of Physics, University of Massachusetts, Amherst, Massachusetts 01002 (current address until Fall of 1973: Prof. Arthur Quinton, Department of Nuclear Physics, Australian National University, Box 4 P. O., Canberra ACT, Australia 2600).

Notation: The letter E after an item indicates elementary level, useful principally for high school and introductory college use; the letter I indicates intermediate (junior, senior) level; and the letter A indicates advanced material, principally suited for senior, graduate level. An asterisk (*) indicates items particularly recommended for introductory study.

Reprints: When ordering, request Resource Letter TQE-1, enclose 25 cents per copy (not in stamps) together with a stamped and self-addressed envelope, to Arnold A. Strassenberg, Executive Officer, American Association of Physics Teachers, Drawer A-W, State University of New York, Stony Brook, New York 11790.
Theorem on the Reality of the Electromagnetic Potentials
Authors: Ingraham R. L.
Published: August 2005

The Bohm-Aharanov effect reminds us that the EM potentials have a certain physical reality even in a fieldfree region if that (multiply connected) region encloses nonzero flux. We prove a theorem which isolates for any such vector field the physically significant, gauge-independent component. Application to “hydrodynamical” quantum mechanics and to the macroscopic quantum states exemplified in superconductivity shows that such curl-less potentials are responsible for nonzero angular momentum, which is another aspect of their physical reality.
Computer Solutions to a Realistic “One-Dimensional” Schrödinger Equation
Authors: Bolemon Jay S.
Published: August 2005

An important technique for teaching introductory wave mechanics is provided by the numerical calculation of stationary state solutions of the Schrödinger equation. Realistic problems in wave mechanics that do not require sophisticated computer techniques are very valuable for the instruction of undergraduates. In the central-field model for atoms, the calculation of electron states reduces to the solution of a one-dimensional differential equation whose numerical solutions are no more difficult to obtain than those for a finite square well. A method used by our students is discussed in this paper for the calculation of the electron wavefunctions in a central-field potential. By working this problem, students obtain meaningful results that give them insight into the theory of atomic structure. Results of their experience are included, and possibilities of extending this example are discussed.
Eigenvalues and Eigenvectors of Angular Momentum Operator Jx without the Theory of Rotations
Authors: Narducci Lorenzo M. , Orszag Miguel
Published: August 2005

We propose an algebraic diagonalization procedure for the angular momentum matrix Jx which is based on the introduction of a suitable generating function. The consideration of the analytic properties of the generating function leads to the eigenvalues of the problem. The coefficients of the power series expansion of this function generate the components of the eigenvectors of Jx. This procedure provides the beginning student of quantum mechanics with an alternative derivation of the eigenvalue spectrum of the angular momentum.
Acoustics for Music Majors—A Laboratory Course
Authors: McDonald Perry F.
Published: August 2005

This article gives brief descriptions of several of the laboratory experiments which have been incorporated into an acoustics course for music majors. These include studies of the vibratory motion and sound generation of musical sound sources, the nature, speed, and pitch of sound, spectrum analysis of musical sounds, electronic synthesis of musical sounds, recording techniques, and the conventional sound experiments normally included in a nonscience physics course.
Physicists and the Elementary Schools—New Strategies for an Old Problem
Authors: Paldy Lester G.
Published: August 2005

Most elementary schools in the United States have inadequate science programs. Despite the existence of excellent curriculum projects that have been developed to provide appropriate laboratory experiences for children, the number of teachers who are poorly prepared to teach science is so large that it will be impossible to use old mechanisms to provide refresher training. An example is given of the way in which a university physics department, supported by the National Science Foundation, has attempted to provide a new model for establishing a working relationship with the elementary schools in its vicinity and has assisted in the introduction of science materials in 425 classrooms.
Elementary Physics Course Presented over Television
Authors: Wager Alan T.
Published: August 2005

The practical aspects of presenting a course in physics by television are discussed.
Anniversaries in 1958 of Interest to Physicists
Authors: Barr E. Scott
Published: August 2005

During the year 1958 there will be one bicentennial, six sesquicentennials, and fourteen centennials of the birth or death of persons of interest to physicists. Brief biographical sketches of these persons are given here.
Problems in the Physics of Meteors
Authors: Öpik E. J.
Published: August 2005

Some basic notions of the physics of meteors are illustrated and recent developments are pointed out. Values of the efficiency of meteor radiation in visible light, formulas for the calculation of meteor masses, tables for the ionizing efficiency, depth of penetration of the ions, and the selectivity of radar observations with respect to velocity are given. The importance of initial penetration of the high velocity ions in determining the radius of the ionizing column, and the selectivity of radar observations, biased against velocities exceeding 50 km/sec, are pointed out. The dust ball nature of visual meteors is described. The insignificant share of nickel-iron in meteoric populations is stressed. Systematic errors in correlating meteor decelerations with atmospheric densities are described.
On the Classical Mechanics of the Internal Rotation of Molecules
Authors: Lin Chun C.
Published: August 2005

The classical solution is given for a symmetric rotor which in addition to the three degrees of freedom corresponding to the over-all rotation has also a degree of freedom for internal rotation about the axis of symmetry. The case of free internal rotation and hindered torsion with a potential barrier of the form 12 V0(1 − cosnα) are discussed. It is found that the classical dipole radiation frequency of a symmetric-top molecule is not affected by the internal rotation.
Speed of Straight Waves in a Ripple Tank
Authors: Clark Clifton Bob
Published: August 2005

The appropriate hydrodynamic relations are developed in a manner that utilizes mathematics which is no more complicated than the expression for the total derivative of a function of more than one variable. Expressions for the speed of propagation are obtained in two cases; first the surface tension is neglected, then it is taken into account. The equation for the trajectories of the particles of water is obtained.
Modern Electronics for the General Student
Authors: Greenslade Thomas B.
Published: August 2005

I have spent a fair proportion of my teaching career working with nonscience college students, showing them something of my world and connecting with their own experiences. One unusual course I developed is Modern Electronics, an alternative to the typical courses offered these students. In the hope that other teachers of introductory physics want to try this approach, I will share my motivations and some of the details of this course.
Association between the Pharmacokinetics and In Vivo Therapeutic Efficacy of Sulfadoxine-Pyrimethamine in Malawian Children
Authors: Dzinjalamala Fraction K. , Macheso Allan , Kublin James G. , Taylor Terrie E. , Barnes Karen I. , Molyneux Malcolm E. , Plowe Christopher V. , Smith Peter J.
Published: August 2005

Sulfadoxine-pyrimethamine (SP) has been widely used in recent years to treat acute uncomplicated
Plasmodium falciparum
malaria. Risk factors for SP therapeutic failure include young age, subtherapeutic SP concentrations, and resistance-conferring genetic mutations in parasite target enzymes. A substantial proportion of patients are able to clear genetically highly resistant
P. falciparum
genotypes. To determine whether blood SP concentrations independently affect the patient's ability to clear resistant genotypes, we compared SP pharmacokinetics of cases of adequate clinical and parasitological response (ACPR) with cases of treatment failure (TF). When patients with ACPR and TF were compared, mean values were similar for the day 3 blood pyrimethamine (205 ng/ml versus 172 ng/ml;
P
= 0.25) and estimated maximum sulfadoxine (79 ± 6.52 versus 69 ± 6.27 μg/ml;
P
= 0.60) concentrations, for sulfadoxine terminal-phase elimination half-lives (7.15 versus 6.41 days;
P
= 0.42), and for the extents of sulfadoxine absorption (areas under the concentration-time curve of 932 ± 100 versus 888 ± 78.9 μg day ml
−1
;
P
= 0.72). Among patients infected with the quintuple resistant parasites, day 3 blood pyrimethamine concentrations were higher in those who cleared the infection than in those who did not (305 ± 35.4 versus 228 ± 21.7 ng/ml;
P
= 0.037). Within this subgroup, this finding remained significant after adjusting for endogenous folate levels, age, site, and resistance-conferring mutations (odds ratio: 1.011 [1.003 to 1.024];
P
= 0.018). However, as a subgroup analysis, our biologically plausible observation that higher blood pyrimethamine concentrations enhance the ability of patients to clear resistant
P. falciparum
should be interpreted with caution and needs further validation.
Candidate Sulfonated and Sulfated Topical Microbicides: Comparison of Anti-Human Immunodeficiency Virus Activities and Mechanisms of Action
Authors: Scordi-Bello Irini A. , Mosoian Arevik , He Cejiang , Chen Yiban , Cheng Yang , Jarvis Gary A. , Keller Marla J. , Hogarty Kathleen , Waller Donald P. , Profy Albert T. , Herold Betsy C. , Klotman Mary E.
Published: August 2005

Poly(styrene 4-sulfonate), cellulose sulfate, polymethylenehydroquinone, and PRO 2000 are sulfated or sulfonated polymers (SPs) under development as topical microbicides. They are presumed to work through similar mechanisms of action, although to date there has been no extensive comparison of their anti-human immunodeficiency virus activities. To determine whether any of these candidate microbicides offers a potential advantage, their in vitro activities, mechanisms of action, stabilities in biological secretions, and toxicities were compared. All four compounds were found to be active against X4, R5, and dualtropic primary isolates and against X4 and R5 laboratory-adapted strains in CD4
+
T cells, macrophages, and single-coreceptor cell lines. Our single-cycle experiments using pseudotyped virus suggest that all four SPs function at the binding and entry stages of the viral life cycle but differ in degree of postentry effect. Surface plasmon resonance analyses demonstrate that SPs bind to X4 and R5 monomeric glycoprotein 120 with similar high binding affinities. When mixed with cervicovaginal lavage fluid, SPs maintain inhibitory activity at concentrations achievable in formulations.
Pharmacodynamics of Polymyxin B against
Pseudomonas aeruginosa
Authors: Tam Vincent H. , Schilling Amy N. , Vo Giao , Kabbara Samer , Kwa Andrea L. , Wiederhold Nathan P. , Lewis Russell E.
Published: August 2005

Despite limited data, polymyxin B (PB) is increasingly used clinically as the last therapeutic option for multidrug-resistant (MDR) gram-negative bacterial infections. We examined the in vitro pharmacodynamics of PB against four strains of
Pseudomonas aeruginosa
. Clonal relatedness of the strains was assessed by random amplification of polymorphic DNA. Time-kill studies over 24 h were performed with approximately 10
5
and 10
7
CFU/ml of bacteria, using PB at 0, 0.25, 0.5, 1, 2, 4, 8, and 16× MIC. Dose fractionation studies were performed using an in vitro hollow-fiber infection model (HFIM) against a wild-type and a MDR strain. Approximately 10
5
CFU/ml of bacteria were exposed to placebo and three regimens (every 8 h [q8h], q12h, and q24h) simulating the steady-state unbound PB pharmacokinetics resulting from a daily dose of 2.5 mg/kg of body weight and 20 mg/kg (8 times the clinical dose). Samples were obtained over 4 days to quantify PB concentrations, total bacterial population, and subpopulation with reduced PB susceptibility (>3× MIC). The bactericidal activity of PB was concentration dependent, but killing was significantly reduced with a high inoculum. In HFIM studies, a significant reduction in bacterial load was seen at 4 h in all active regimens, but selective amplification of the resistant subpopulation(s) was apparent at 24 h with the clinical dose (both strains). Regrowth was eventually observed in all dosing regimens with the MDR strain, but its occurrence was prevented in the wild-type strain by using 8 times the clinical dose (regardless of dosing intervals). Our results suggested that the bactericidal activity of PB was concentration dependent and appeared to be related to the ratio of the area under the concentration-time curve to the MIC.
Pharmacological Properties of a New Antimalarial Bisthiazolium Salt, T3, and a Corresponding Prodrug, TE3
Authors: Nicolas Olivier , Margout Delphine , Taudon Nicolas , Wein Sharon , Calas Michèle , Vial Henri J. , Bressolle Françoise M. M.
Published: August 2005

A new approach to malarial chemotherapy based on quaternary ammonium that targets membrane biogenesis during intraerythrocytic
Plasmodium falciparum
development has recently been developed. To increase the bioavailability, nonionic chemically modified prodrugs were synthesized. In this paper, the pharmacological properties of a bisthiazolium salt (T3) and its bioprecursor (TE3) were studied. Their antimalarial activities were determined in vitro against the growth of
P. falciparum
and in vivo against the growth of
P. vinckei
in mice. Pharmacokinetic evaluations were performed after T3 (1.3 and 3 mg/kg of body weight administered intravenously; 6.4 mg/kg administered intraperitoneally) and TE3 (1.5 and 3 mg/kg administered intravenously; 12 mg/kg administered orally) administrations to rats. After intraperitoneal administration, very low doses offer protection in a murine model of malaria (50% efficient dose [ED
50
] of 0.2 to 0.25 mg/kg). After oral administration, the ED
50
values were 13 and 5 mg/kg for T3 and TE3, respectively. Both compounds exerted antimalarial activity in the low nanomolar range. After TE3 administration, rapid prodrug-drug conversion occurred; the mean values of the pharmacokinetic parameters for T3 were as follows: total clearance, 1 liter/h/kg; steady-state volume of distribution, 14.8 liters/kg; and elimination half-life, 12 h. After intravenous administration, T3 plasma concentrations increased in proportion to the dose. The absolute bioavailability was 72% after intraperitoneal administration (T3); it was 15% after oral administration (TE3). T3 plasma concentrations (8 nM) 24 h following oral administration of TE3 were higher than the 50% inhibitory concentrations for the most chloroquine-resistant strains of
P. falciparum
(6.3 nM).
Risk Factors for Acquisition of Multidrug-Resistant
Pseudomonas aeruginosa
Producing SPM Metallo-β-Lactamase
Authors: Nouér Simone Aranha , Nucci Marcio , de-Oliveira Márcia P. , Pellegrino Flávia Lúcia Piffano Costa , Moreira Beatriz Meurer
Published: August 2005

To evaluate risk factors for colonization or infection due to multidrug-resistant
Pseudomonas aeruginosa
(MDRPa) carrying the
bla
SPM
gene (SPM-MRDPa) among hospitalized patients, we undertook a case control study at a 480-bed, tertiary-care university hospital. Two different case definitions were used. In the first definition, a case patient (SPM case patient) was defined as a patient who had at least one isolate of SPM-MDRPa (14 patients). In the second, a case patient (non-SPM case patient) was defined as a patient who had at least one isolate of non-SPM-MDRPa (18 patients). For each case patient, we selected two controls, defined as a patient colonized and/or infected by a non-MDRPa isolate during the same study period and with the closest duration of hospitalization until the isolation of
P. aeruginosa
as cases. The use of quinolones was the single independent predictor of colonization and/or infection by
bla
SPM
MDRPa (odds ratrio [OR] = 14.70, 95% confidence interval [95% CI] = 1.70 to 127.34,
P
= 0.01), whereas the use of cefepime was the single predictor of colonization and/or infection by non-
bla
SPM
MDRPa (OR = 8.50, 95% CI = 1.51 to 47.96,
P
= 0.01). The main risk factor for MDRPa was a history of antibiotics usage. Stratification of risk factor analysis by a precise mechanism of resistance led us to identify a specific antibiotic, a quinolone, as a predictor for SPM-MDRPa.
Effect of Recombinant Murine Granulocyte Colony-Stimulating Factor with or without Fluoroquinolone Therapy on Mixed-Infection Abscesses in Mice
Authors: Stearne Lorna E. T. , Vonk Alieke G. , Kullberg Bart Jan , Gyssens Inge C.
Published: August 2005

The aim of the study was to determine if immunomodulation of host defense with recombinant murine granulocyte colony-stimulating factor (G-CSF) improves the efficacy of trovafloxacin or moxifloxacin in abscesses containingBacillus fragilisATCC 23745 and differentEscherichia colistrains varying in virulence. Treatment of mice inoculated with 107CFUB. fragilisand 105CFU low-virulenceE. coliwith either trovafloxacin (150 mg/kg/day every 24 hours, days 3 to 7) or moxifloxacin (96 mg/kg/day every 12 hours, days 3 to 7), significantly reduced the number ofB. fragilisto 6.9 ± 0.35 and 5.8 ± 0.10 and that ofE. colito 4.9 ± 0.09 and 4.2 ± 0.07 log CFU/abscess for trovafloxacin and moxifloxacin, respectively, compared to controls (B. fragilis8.7 andE. coli7.4 log CFU/abscess) on day 8. Also, moxifloxacin was more potent than trovafloxacin. Addition of G-CSF prophylaxis (1 μg once on day −1) or therapy (1 μg/day on days 3 to 7) to fluoroquinolone treatment did not improve the efficacy of fluoroquinolone therapy alone. The effect of moxifloxacin with or without G-CSF prophylaxis on abscesses with a virulent hemolyticE. colistrain was also studied. In moxifloxacin-treated mice, 75% survived infection compared to 10% of controls. Combining moxifloxacin with G-CSF prophylaxis significantly decreased survival (30%) compared to moxifloxacin alone. In addition, G-CSF prophylaxis resulted in a threefold (E. coli) to 100-fold (B. fragilis) increased outgrowth in the abscesses of surviving mice. In conclusion, the addition of G-CSF to a fluoroquinolone is not advisable since, depending on the virulence of theE. colistrains, this might detrimentally influence the outcome of therapy.