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Ultrasonic energy—biological investigations and medical applications
considerable interest to the physicist ot engineer working with ultrasonic waves, and the fundamentals of each topic are well described by the author. The book is written principally for students in the first two years of an honours physics course, and discussions are therefore not solely in terms of acoustic or ultrasonic waves, examples being drawn also from optics, and from The treatment is electromagnetics. mainly theoretical, but the mathematical arguments are at a fairly elementary level and should not cause difficulties to most readers. This book might well be found useful by the engineer particularly engaged in work on ultrasonic systems who wishes to extend his understanding of certain general physical fundamentals. For example, his formal training will frequently not have included any reference to diffraction, yet his understanding of the field produced by an ultrasonic radiator will indeed be superficial if he is not acquainted with certain general principles underlying all diffraction phenomena. Again, he may wish to study certain important principles of dispersion. in order to understand the distortion of an ultrasonic pulse. Particular emphasis is placed by the author on Fourier methods. and this again will be found useful by the reader interested in the frequency spectrum of an ultrasonic pulse, or the application of the Fourier transform to diffraction from a source. As the author remarks “most of the topics will not be strange to a university physics student: the emphasis here is on the strong line of common thought which goes through them.” This line of common thought will be of interest to someone concerned with the production and propagation of ultrasonic waves; he should therefore find this book interesting and useful in broadening his understanding of basic ideas. M. REDWOOD
Ultrasound-Physical. Chemical and Biological Effects /IV 1. E. E/‘piner, trtrw.rfkom I/W Russitur hr. F. L. Sin&tit., Con.s//lran~.s Bwcw//, Nc,I~~ Yotk ( 1964). 371 pp. $22.50. This English edition of a book already known to some is a welcome addition to the literature of the biophysics of ultrasound. The author, Isaac El’piner. is already well known for his experimental studies on the degradation of biological polymers by ultrasonic waves. From the foreword it is plain that hc has also had advice from other distinguished Russian colleagues in the field. The first third of the book is devoted to an authoritative exposition of the physics of ultrasonic energy, particularly sonically induced lrittd
cavitation and its attendant phenomena such as sonoluminescence. The chapters on the chemical effects of cavitation are. as would be expected, fully developed and those on the chemical effects of ultrasound on biological polymers particularly useful. Two chapters are devoted to describing the changes induced in living systems by ultrasonic fields and a final chapter discusses briefly biological sonography and gives extremely brief references to the investigation of molecular structure by sound. The book is especially valuable for the very comprehensive lists of references given at the end of each chapter. Unfortunately, these. with few exceptions, do not extend beyond 1960: this is true mainly of the more biological chapters. No theory of the various effects of ultrasound in biological systems such as living cells is put forward with any clarity. It would be difficult for those new to this field to decide from this book which of the physical effects in a sound field is considered the important one in producing changes even in isolated systems. The general trend of the book therefore reflects the incoherent state of this held up to about 1960. However, where much of the work already done was being reviewed it would have been expected that a greater attempt to correlate the phenomena would have to be made. Part of the trouble arises from the overwhelming importance given to the chemical effects of cavitation. This is seen clearly on page 30 where ultrasonic effects are divided into four groups. Each of these groups is a chemical effect ; in the gas phase, in bubble liquid interface, free radical formation, and theeffect of shock waves. Barely mentioned are the inactivation of enzymes or degradation of DNA and proteins by heat or mechanical stress induced by oscillations or streaming in inhomogeneous sound fields, which must be taken into account, particularly in non-cavitating fields. In considering the effects of ultrasound in living cells the author uses the results of intense and cavitating sound fields for explaining the biological effects of less intense and non-cavitating fields. For instance, an overwhelming mass of experiment in the field of microbiology is concerned with the use of intense ultrasound IO release enzymes from the cells by disintegrating them into fine fragments. This is described fairly fully and rather uncritically. While it is extremely important to the technology of enzymology it has little to add to our understanding the mechanisms of the biological effects of ultrasound. Here, too. it is difficult to make any comparisons of the various effects described because the actual physical parameters of the sound fields used in this work are either unknown or not described. Some difficulty here may arise from a basic difference of outlook. It was apparent to
the reviewer in private conversation that many Russian microbiologists do not accept the importance given to studies on isolated cell components in Europe and U.S.A.. that is to the approach becoming morphology.” known as “analytical Certainly Chapters 9 and IO should serve to convince the author’s colleagues of the value of this approach and in particular of the important role that ultrasonics plays in this rapidly growing held. Even with these shortcomings this is ;I valuable book as an introduction to the field to those not already engaged in it. To those already working in this field the book will serve as the best available source of references and the subject matter will be a constant reminder 01 work yet to be done before we understand how sound wavjes produce changes in biological systems as diverse as the human brain on the one hand LIIKI micro-organisms such as bacteria and virusi s on the other.
Marine 7-two/gt/
bioacoustics
/>,I,
Wi//ir/rrr
.V.
( &d.), Prrgc/rmn ( 1964).
This book constitutes the proceedings 01 a symposium held at the Lerner Marine Laboratory. Bimini. Bahamas, in April, 1963. It includes the text of the formal presentations as well ad a transcription of the general discussion. Though not organized in a fashion which would lend itself to being used as a textbook. it is essential reading for anyone directly concerned with this field. Topics include of underwater apparatus description (acoustic, electronic and television). the occurrence of various underwater so~~nds, sound production and reception by various marine animals, topics in physical mechanisms, hearing acuity in tishes. echo location by cetaceans, and dolphin communication. Some of this material is not elsewhere available, and this book supplies a convenient compendium of these rather diverse papers. the second of these Incidentally. symposia is scheduled to be held at the American Museum of Natural History in New York in April 1966. and a second volume should follow. I<. 5. M(‘K,\‘,
Ultrasonic energy-Biological investigations and medical applications />.I, Eli;rrhrtfl
Kelly (Ed. ). Utrir.oxit,v of’ Pwxv, Urbma, 1llitroi.v. U.S.A. ( 1965). 387 pp., $12.50. In June 1962 the University of Illinois held a conference on medical and biological ultrasonics. This book is the ouIllinois
come. lt contains the papers and discussions, carefully edited and beautifully illustrated. Of the 26 chapters, eight deal with diagnosis, four with ultrasound surgery and five with the biological effects of ultrasound on tissues at all intensities. The remainder cover physical medicine and the effects on liver, malignant cells, the neurovascular system and the ear. As most of the world’s experts in ultrasonics attended the conference, the book has authority: good editing and production give it clarity: but the three years’ delay in publishing makes many of the papers out of date: the paper on scanning techniques is an example. And there are only a handful of references after 1962. This is a pity because although most of the material has been published elsewhere, there exists no comparable summary of medical ultrasonics. Newcomers to ultrasonics in the last three years would have found this book invaluable as an introductory textbook.
Principles of electronics in medical research hy D. W. Hill. Butterworth, London 1965. 288 pp., 61s. 6d. The rapid growth of electronic applications in medicine and biology has left many doctors using techniques with which they are not as familiar as they would like to be. The function of electronic equipment must be known in order to assess any possible source of error in a measurement and to understand its interrelationship with an experiment, particularly with more complex equipment such as data processing and computation. The medical scientist therefore needs a book which explains the basic principles of electrcnics and relates them to familiar applications. This book is written for medical doctors and others who are responsible for electronics staff but who do not require a detailed knowledge of electronics. The subject matter for this purpose is well chosen with perhaps a few notable omissions such as photocells and microwaves. The main difficulty in writing this type of book is in achieving a reasonable compromise between an adequate level of presentation, which might be difficult for the average reader to follow and a simple approach which only succeeds in imparting superficial information. An author is therefore open to criticism in that he may err in either direction and in this case the author has perhaps favoured the simplified approach. For instance, switching circuits, a basic subject of modern electronics, are dealt with in II pages so that sketchy descriptions have had to be used. There is a danger that statements of fact may
be misleading through omission, as in the explanation of negative feedback which does not mention alternative systems and leaves the reader with the impression that one effect of negative feedback is to increase the input impedance. Explanations of a.c. interference fail because of insufficient detail and would have been better left at the elementary level. The chapter on semiconductors is very well done, with sufficient detail at a level which the intelligent reader could follow. The principles of electronics do not change with the method of application so any advantage of this book over the conventional elementary textbook in electronics would be in linking these principles with applications in medical research. This is done to a certain extent but often applications are mentioned and referred to, rather than using them when The last explaining the principles. chapter on transducers is more in line with this approach and will be of particular interest to the medical reader. The publishers are to be commended in associating the figures with the text. The references quoted are mostly to applications and not to recommend textbooks for further reading which would have been most useful. The book is very readable and the medical doctor should obtain from it a better general understanding of electronics. He should, however, appreciate the amount of information engineers might obtain from a similar book “Medicine for engineers” in 300 pages. W. .I. PERKINS
Pulse, digital and switching waveforms by J. Millman and H. Taub. McGraw-Hill ( 1965). 958 pp., 120s. An excellent book for the student and a useful reference book; each chapter is plentifully supplied with prcblems for the student so that it could form a good textbook in a lecture course on this subject. The authors have generally succeeded in giving an understanding of the circuit design performance, introducing sufficient theory to permit the necessary design calculations, but without attempting to derive the basic formulae quoted from semiconductor physics theory; the reader is expected to have some knowledge of Laplace transBoth transistor and form theory. thermionic valve circuits are treated, with the main emphasis on the semiconductor circuit design. The first three chapters are devoted to basic network theorems and passive circuits: input and output impedances of “fed-back” amplifiers; equivalent circuits of transistors and valves; RC and RLC shaping circuits under pulse, step
and ramp function excitation: pulse transformers and delay lines, including nanosecond coaxial cable transformers. These chapters are all very good with the exception of lumped delay lines to which no reference is made until later on in the book. Also the case of the deterioration of pulse shape on transmission through a long cable has been omitted. Chapters 4 and 5 treat wideband amplifiers, including the “distributed thermionic valve” type an3 various inductive compensated circuits, but one important omission is a treatment of amplifiers with a high degree of negative feedback, to give gain stability and linearity combined with moderate bandwidth. The next chapters deal with low-speed switching of diodes, transistors and valves with application to clipping, comparator, clamping and switching circuits: there is no adequate discussion of the effect of collector resistance on comparator circuits. Chapter 9 is an excellent introduction to Boolean algebra and the concept of logic circuits whilst Chapters IO and 11 deal with binary and monostable circuits. The circuit descriptions in these last two chapters tend to be rather too lengthy with the important relations of circuit memory and input trigger pulse duration not being clearly outlined. Again, the essential addition of a self-starting feature to a crosscoupled free-running transistor multivibrator has been relegated to one of the problems. The next two chapters give an excellent and up-to-date survey of negative resistance devices and circuits, including tunnel diodes, various p-n-p-n devices and avalanche transistors. There follow chapters on voltage and current timebase generators but I would have preferred some better discussion on current feedback in current timebase generators; blocking oscillators are then described. There follows a very good survey of sampling gates, including diode bridges, FET and double emitter transistors for use in chopper d.c. amplifiers and such applications as the sampling oscilloCounting, timing, synchronizascope. tion and frequency division are then adequately covered. The book finishes by one of its best chapters on the switching of diodes and transient transistors with the charge control concept being described. Thus, to conclude, this book gives a complete coverage of the subject, and is easy to read. In a few places the description is too lengthy and may obscure the Howmore important characteristics. ever, this book can be thoroughly recommended both for student study and for an up-to-date reference book on this important and rapidly expanding field of electronics. F. H. M’ELLS
ULTRASONI~S/AprI’~ I966
105
Ultrasound-Physical. Chemical and Biological Effects /IV 1. E. E/‘piner, trtrw.rfkom I/W Russitur hr. F. L. Sin&tit., Con.s//lran~.s Bwcw//, Nc,I~~ Yotk ( 1964). 371 pp. $22.50. This English edition of a book already known to some is a welcome addition to the literature of the biophysics of ultrasound. The author, Isaac El’piner. is already well known for his experimental studies on the degradation of biological polymers by ultrasonic waves. From the foreword it is plain that hc has also had advice from other distinguished Russian colleagues in the field. The first third of the book is devoted to an authoritative exposition of the physics of ultrasonic energy, particularly sonically induced lrittd
cavitation and its attendant phenomena such as sonoluminescence. The chapters on the chemical effects of cavitation are. as would be expected, fully developed and those on the chemical effects of ultrasound on biological polymers particularly useful. Two chapters are devoted to describing the changes induced in living systems by ultrasonic fields and a final chapter discusses briefly biological sonography and gives extremely brief references to the investigation of molecular structure by sound. The book is especially valuable for the very comprehensive lists of references given at the end of each chapter. Unfortunately, these. with few exceptions, do not extend beyond 1960: this is true mainly of the more biological chapters. No theory of the various effects of ultrasound in biological systems such as living cells is put forward with any clarity. It would be difficult for those new to this field to decide from this book which of the physical effects in a sound field is considered the important one in producing changes even in isolated systems. The general trend of the book therefore reflects the incoherent state of this held up to about 1960. However, where much of the work already done was being reviewed it would have been expected that a greater attempt to correlate the phenomena would have to be made. Part of the trouble arises from the overwhelming importance given to the chemical effects of cavitation. This is seen clearly on page 30 where ultrasonic effects are divided into four groups. Each of these groups is a chemical effect ; in the gas phase, in bubble liquid interface, free radical formation, and theeffect of shock waves. Barely mentioned are the inactivation of enzymes or degradation of DNA and proteins by heat or mechanical stress induced by oscillations or streaming in inhomogeneous sound fields, which must be taken into account, particularly in non-cavitating fields. In considering the effects of ultrasound in living cells the author uses the results of intense and cavitating sound fields for explaining the biological effects of less intense and non-cavitating fields. For instance, an overwhelming mass of experiment in the field of microbiology is concerned with the use of intense ultrasound IO release enzymes from the cells by disintegrating them into fine fragments. This is described fairly fully and rather uncritically. While it is extremely important to the technology of enzymology it has little to add to our understanding the mechanisms of the biological effects of ultrasound. Here, too. it is difficult to make any comparisons of the various effects described because the actual physical parameters of the sound fields used in this work are either unknown or not described. Some difficulty here may arise from a basic difference of outlook. It was apparent to
the reviewer in private conversation that many Russian microbiologists do not accept the importance given to studies on isolated cell components in Europe and U.S.A.. that is to the approach becoming morphology.” known as “analytical Certainly Chapters 9 and IO should serve to convince the author’s colleagues of the value of this approach and in particular of the important role that ultrasonics plays in this rapidly growing held. Even with these shortcomings this is ;I valuable book as an introduction to the field to those not already engaged in it. To those already working in this field the book will serve as the best available source of references and the subject matter will be a constant reminder 01 work yet to be done before we understand how sound wavjes produce changes in biological systems as diverse as the human brain on the one hand LIIKI micro-organisms such as bacteria and virusi s on the other.
Marine 7-two/gt/
bioacoustics
/>,I,
Wi//ir/rrr
.V.
( &d.), Prrgc/rmn ( 1964).
This book constitutes the proceedings 01 a symposium held at the Lerner Marine Laboratory. Bimini. Bahamas, in April, 1963. It includes the text of the formal presentations as well ad a transcription of the general discussion. Though not organized in a fashion which would lend itself to being used as a textbook. it is essential reading for anyone directly concerned with this field. Topics include of underwater apparatus description (acoustic, electronic and television). the occurrence of various underwater so~~nds, sound production and reception by various marine animals, topics in physical mechanisms, hearing acuity in tishes. echo location by cetaceans, and dolphin communication. Some of this material is not elsewhere available, and this book supplies a convenient compendium of these rather diverse papers. the second of these Incidentally. symposia is scheduled to be held at the American Museum of Natural History in New York in April 1966. and a second volume should follow. I<. 5. M(‘K,\‘,
Ultrasonic energy-Biological investigations and medical applications />.I, Eli;rrhrtfl
Kelly (Ed. ). Utrir.oxit,v of’ Pwxv, Urbma, 1llitroi.v. U.S.A. ( 1965). 387 pp., $12.50. In June 1962 the University of Illinois held a conference on medical and biological ultrasonics. This book is the ouIllinois
come. lt contains the papers and discussions, carefully edited and beautifully illustrated. Of the 26 chapters, eight deal with diagnosis, four with ultrasound surgery and five with the biological effects of ultrasound on tissues at all intensities. The remainder cover physical medicine and the effects on liver, malignant cells, the neurovascular system and the ear. As most of the world’s experts in ultrasonics attended the conference, the book has authority: good editing and production give it clarity: but the three years’ delay in publishing makes many of the papers out of date: the paper on scanning techniques is an example. And there are only a handful of references after 1962. This is a pity because although most of the material has been published elsewhere, there exists no comparable summary of medical ultrasonics. Newcomers to ultrasonics in the last three years would have found this book invaluable as an introductory textbook.
Principles of electronics in medical research hy D. W. Hill. Butterworth, London 1965. 288 pp., 61s. 6d. The rapid growth of electronic applications in medicine and biology has left many doctors using techniques with which they are not as familiar as they would like to be. The function of electronic equipment must be known in order to assess any possible source of error in a measurement and to understand its interrelationship with an experiment, particularly with more complex equipment such as data processing and computation. The medical scientist therefore needs a book which explains the basic principles of electrcnics and relates them to familiar applications. This book is written for medical doctors and others who are responsible for electronics staff but who do not require a detailed knowledge of electronics. The subject matter for this purpose is well chosen with perhaps a few notable omissions such as photocells and microwaves. The main difficulty in writing this type of book is in achieving a reasonable compromise between an adequate level of presentation, which might be difficult for the average reader to follow and a simple approach which only succeeds in imparting superficial information. An author is therefore open to criticism in that he may err in either direction and in this case the author has perhaps favoured the simplified approach. For instance, switching circuits, a basic subject of modern electronics, are dealt with in II pages so that sketchy descriptions have had to be used. There is a danger that statements of fact may
be misleading through omission, as in the explanation of negative feedback which does not mention alternative systems and leaves the reader with the impression that one effect of negative feedback is to increase the input impedance. Explanations of a.c. interference fail because of insufficient detail and would have been better left at the elementary level. The chapter on semiconductors is very well done, with sufficient detail at a level which the intelligent reader could follow. The principles of electronics do not change with the method of application so any advantage of this book over the conventional elementary textbook in electronics would be in linking these principles with applications in medical research. This is done to a certain extent but often applications are mentioned and referred to, rather than using them when The last explaining the principles. chapter on transducers is more in line with this approach and will be of particular interest to the medical reader. The publishers are to be commended in associating the figures with the text. The references quoted are mostly to applications and not to recommend textbooks for further reading which would have been most useful. The book is very readable and the medical doctor should obtain from it a better general understanding of electronics. He should, however, appreciate the amount of information engineers might obtain from a similar book “Medicine for engineers” in 300 pages. W. .I. PERKINS
Pulse, digital and switching waveforms by J. Millman and H. Taub. McGraw-Hill ( 1965). 958 pp., 120s. An excellent book for the student and a useful reference book; each chapter is plentifully supplied with prcblems for the student so that it could form a good textbook in a lecture course on this subject. The authors have generally succeeded in giving an understanding of the circuit design performance, introducing sufficient theory to permit the necessary design calculations, but without attempting to derive the basic formulae quoted from semiconductor physics theory; the reader is expected to have some knowledge of Laplace transBoth transistor and form theory. thermionic valve circuits are treated, with the main emphasis on the semiconductor circuit design. The first three chapters are devoted to basic network theorems and passive circuits: input and output impedances of “fed-back” amplifiers; equivalent circuits of transistors and valves; RC and RLC shaping circuits under pulse, step
and ramp function excitation: pulse transformers and delay lines, including nanosecond coaxial cable transformers. These chapters are all very good with the exception of lumped delay lines to which no reference is made until later on in the book. Also the case of the deterioration of pulse shape on transmission through a long cable has been omitted. Chapters 4 and 5 treat wideband amplifiers, including the “distributed thermionic valve” type an3 various inductive compensated circuits, but one important omission is a treatment of amplifiers with a high degree of negative feedback, to give gain stability and linearity combined with moderate bandwidth. The next chapters deal with low-speed switching of diodes, transistors and valves with application to clipping, comparator, clamping and switching circuits: there is no adequate discussion of the effect of collector resistance on comparator circuits. Chapter 9 is an excellent introduction to Boolean algebra and the concept of logic circuits whilst Chapters IO and 11 deal with binary and monostable circuits. The circuit descriptions in these last two chapters tend to be rather too lengthy with the important relations of circuit memory and input trigger pulse duration not being clearly outlined. Again, the essential addition of a self-starting feature to a crosscoupled free-running transistor multivibrator has been relegated to one of the problems. The next two chapters give an excellent and up-to-date survey of negative resistance devices and circuits, including tunnel diodes, various p-n-p-n devices and avalanche transistors. There follow chapters on voltage and current timebase generators but I would have preferred some better discussion on current feedback in current timebase generators; blocking oscillators are then described. There follows a very good survey of sampling gates, including diode bridges, FET and double emitter transistors for use in chopper d.c. amplifiers and such applications as the sampling oscilloCounting, timing, synchronizascope. tion and frequency division are then adequately covered. The book finishes by one of its best chapters on the switching of diodes and transient transistors with the charge control concept being described. Thus, to conclude, this book gives a complete coverage of the subject, and is easy to read. In a few places the description is too lengthy and may obscure the Howmore important characteristics. ever, this book can be thoroughly recommended both for student study and for an up-to-date reference book on this important and rapidly expanding field of electronics. F. H. M’ELLS
ULTRASONI~S/AprI’~ I966
105