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Seismic imaging has been continuously advancing since the early days of computer revolution in the 1970s. Practical imaging during this time was carried out only in two dimensions using simplified wave equations on poststack data. Subsequently, in the early 1980s algorithm improvements in wave equation migration after the introduction of one-way phase shift methods and two-way reverse time migration occurred. Concurrently, improvements in ray-based Kirchhoff migration emerged after the introduction of eikonal and wavefront reconstruction solvers for calculation of travel times. In the late 1980s, 3D prestack Kirchhoff migration began to be used. By the early 1990s, 3D wave equation poststack migration began to be used and was followed shortly by implementation of wave equation prestack migration. After the turn of the century, 3D prestack reverse time migration became practical, and a few years later VTI, TTI, and orthorhombic rheology were introduced into the imaging.

Foliar application of nutrient fertilizers is standard practice in agricul- tural environments, and has been shown to increase crop yield and quality more efficiently and economically than soil-based fertilizers. The adsorption of macro- and micro-nutrients through the upper epidermis of leaves is largely species dependent; reliant upon pene- tration through the cuticle and stomata, and also upon the plant’s ability to translocate the nutrient. Herein we describe a method to observe nitrate (NO3) uptake at the adaxial leaf surface to deter- mine the efficacy of foliar fertilizers. We use Raman microspectro- scopy as a sensitive approach to monitor NO3 associated vibrational modes, complemented by ion probe measurements and measurements of leaf nutrient status using flame atomic absorption spectroscopy. The results show that NO3 uptake can be observed down to concentrations as low as 15 mM using Raman microspectro- scopy over a defined surface area, and that the rate of uptake can also be quantified using this approach. These observations could also infer information regarding the transport of other ions present in nitrate salts, such as calcium (Ca), via the indirect monitoring of NO3- specific bands. We believe that Raman microspectroscopy pro- vides a novel method for monitoring nutrient movement throughout plant tissue, and provides a potential tool for nutrient screening.

Botrytis cinerea (Grey mould) is a necrotrophic fungus infecting over 230 plant species worldwide. It can cause major pre- and post-harvest diseases of many agronomic and horticultural crops. Botrytis cinerea causes annual economic losses of 10–100 billion US dollars worldwide and instability in the food supply (Jin and Wu, 2015). Grey mould losses, either at the farm gate or later in the food chain, could be reduced with improved knowledge of inoculum availability during production. In this paper, we report on the ability to monitor Botrytis spore concentration in glasshouse tomato production ahead of symptom development on plants. Using a light weight and portable air sampler (microtitre immunospore trap) it was possible to quantify inoculum availability within hours. Also, this study investigated the spatial aspect of the pathogen with an increase of B. cinerea concentration in bio-aerosols collected in the lower part of the glasshouse (0.5 m) and adjacent to the trained stems of the tomato plants. No obvious relationship was observed between B. cinerea concentration and the internal glasshouse environmental parameters of temperature and relative humidity. However the occurrence of higher outside wind speeds did increase the prevalence of B. cinerea conidia in the cropping environment of a vented glasshouse. Knowledge of inoculum availability at time periods when the environmental risk of pathogen infection is high should improve the targeted use and effectiveness of control inputs.

Health care reform has been a prominent issue in American politics for the past century. With the exception of the passage of Medicare and Medicaid legislation in 1965, Congress has not significantly reformed health care legislation in recent history. One attempt at reform, the case of Bill Clinton's National Health Security Act (HSA), stands out. HSA was "one of the most comprehensive domestic policy proposals made by an American president in this (20th) century,"1 one of the longest-lasting (1993-1996) and most intense policy debates, and it led scholars to conclude that the media played a role in its eventual failure.2Researchers generally confirmed the public's perception that, with only 44 percent of Americans thinking that the media were doing a "good job" of covering the issue in September 1993 and only 32 percent thinking so in August 1994, "the media flunked the job."3 Reporters affected the result by failing to provide the public with the quality of information that, as Gans puts it, is necessary for the proper functioning of society.4 Journalists treated the debate like they tend to treat elections, focusing on "tactics over issues, attack over advocacy, and scandal over substance."5Yet the media had another chance. With health care expenditures rising from $714 billion in 1990 to more than $2.2 trillion in 2007,6 health care was a central election issue in 2008 and a priority for President Obama. And while the issue got off to a slow start-Pew reported that only 7 percent of news coverage was devoted to it in mid-June 20097-health care accounted for a third of all news coverage in August8 and was one of Americans' most closely followed issues throughout the fall.9 This was true despite the public perception of low-quality news coverage. For, just as in 1993, public comprehension fell as coverage rose: 63 percent of Americans said the issue was hard to understand in July 2009, and 67 percent said so in September. Moreover, Americans regarded coverage to be defined by conflict.10While such allegations would be alarming about any news coverage, they are especially discouraging if true about health care reform. Because reform could affect Americans of every age, state and tax bracket, it is likely that citizens would attempt to inform themselves of the issues, form an opinion on the proposed legislation, and finally voice their opinion in a process that leads to the ideal of participatory government.11 As Tuchman put it, "The news media set the frame in which citizens discuss public events and the debate necessarily depends on the information available."12 The question, then, is if newspapers in 2009 and 2010 provided citizens with the type of news needed to make informed decisions, or, to the contrary, followed the lead of the 1993 press coverage. To answer this question, the authors applied news framing theory to analyze how three elite newspapers covered the 14-month health care debate and sought to further framing and policy research by also investigating sourcing, the change in frames and sources over time and the source-frame relationship.Literature ReviewJournalists frame events, actors and issues "through the use of selection, emphasis, exclusion, and elaboration."13 News frames can highlight and legitimize particular aspects of reality while marginalizing others,14 and scholars have found that frames can shape citizens' support of various policies.15Scholars have recognized and defined certain generic frames that are applicable to different news topics.16 Perhaps the best regarded is the issue frame, because it is based on "hard news" and substantive information that "is presumably important to citizens' ability to understand and respond to the world of public affairs."17 An issue-framed story includes the core facts of who's involved, what's involved and what's at stake. It puts information in context and explains its history or implications.18While arguably allowing the media to fulfill their social responsibility best, the issue frame may not be a popular choice of market-driven journalism because it's costly and perceived as failing to attract readers who seek human-interest, emotional news. …

Prospecting demands positive future orientation, hope, sometimes not even knowing what it is you might discover. We were hopeful prospectors on our first LEED project, not exactly sure what we might strike. We sought silver sustainability for the University of New Mexico (UNM) College of Education Building (COE); what we discovered was even more precious and rare, platinum. Getting there entailed chipping away at each sustainable LEED credit until we hit pay dirt, the first publicly-funded and second LEED Platinum building in New Mexico. Gregory T. Hicks & Associates P.C. Architects was contracted by UNM to design a LEED Silver Certified building for its new COE Administration and Classroom Building, Phase 1. All new, state-funded buildings in New Mexico must achieve a minimum LEED Silver certification as mandated by Governor's Executive Order. Two of our staff, Jim MacGillivray and Jay Davis, are LEED APs, and our Principal, Gregory T. Hicks, has taken several USGBC courses, but this being our f...

A semiempirical procedure is developed for the calculation of the dispersion of refractive index, polarizability, and dielectric permeability which are treated as complex quantities. A good agreement between calculated and observed values of refractive indices is obtained for all substances treated. The previously determined values for the static polarizability agree with the present results for the contribution of the electronic motion to the polarizability, this contribution being about the same for both the liquid and gaseous states of hydrogen, oxygen, and water. The value obtained for the static polarizability of liquid water is about 2.8 fold greater than the results of previous calculations; it is conjectured that most of the contribution is due to atomic and molecular motions.

Codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae), is a worldwide pest of apple and pear. Due to the severity of codling moth in agroecosystems, it is a quarantine pest in countries where it is not considered an established species. Detection of codling moth infestations in exports intended for these countries is crucial to the U.S. apple industry. Tests were conducted on infrared thermoimaging that demonstrate detection of infestation by codling moth larva in apples. The system is dependent on subtle but significant differences in surface temperature between infested or entry sites and nearby uninfested sites. Because the imaging data are digital, computer programs can be used to rapidly and effectively sort infested fruits from the packing line.

Integrin alpha4beta1 plays an important role in inflammatory processes by regulating the migration of leukocytes into inflamed tissues. Previously, we identified BIO5192 [2(S)-{[1-(3,5-dichloro-benzenesulfonyl)-pyrrolidine-2(S)-carbonyl]-amino}-4-[4-methyl-2(S)-(methyl-{2-[4-(3-o-tolyl-ureido)-phenyl]-acetyl}-amino)-pentanoylamino]-butyric acid], a highly selective and potent (K(D) of 9 pM) small molecule inhibitor of alpha4beta1. Although BIO5192 is efficacious in various animal models of inflammatory disease, high doses and daily treatment of the compound are needed to achieve a therapeutic effect because of its relatively short serum half-life. To address this issue, polyethylene glycol modification (PEGylation) was used as an approach to improve systemic exposure. BIO5192 was PEGylated by a targeted approach in which derivatizable amino groups were incorporated into the molecule. Two sites were identified that could be modified, and from these, five PEGylated compounds were synthesized and characterized. One compound, 2a-PEG (K(D) of 19 pM), was selected for in vivo studies. The pharmacokinetic and pharmacodynamic properties of 2a-PEG were dramatically improved relative to the unmodified compound. The PEGylated compound was efficacious in a rat model of experimental autoimmune encephalomyelitis at a 30-fold lower molar dose than the parent compound and required only a once-a-week dosing regimen compared with a daily treatment for BIO5192. Compound 2a-PEG was highly selective for alpha4beta1. These studies demonstrate the feasibility of PEGylation of alpha4beta1-targeted small molecules with retention of activity in vitro and in vivo. 2a-PEG, and related compounds, will be valuable reagents for assessing alpha4beta1 biology and may provide a new therapeutic approach to treatment of human inflammatory diseases.

The UK team from Shrewsbury School performed very well in this year's International Young Physicists' Tournament and learnt a lot of physics in the process. This article describes the format of the competition and the team's approach.

Integrin alpha 4 beta 1 plays an important role in inflammatory processes by regulating the migration of lymphocytes into inflamed tissues. Here we evaluated the biochemical, pharmacological, and pharmacodynamic properties and efficacy in experimental autoimmune encephalomyelitis (EAE), a model of multiple sclerosis, of two types of alpha 4 beta 1 inhibitors, the anti-rat alpha 4 monoclonal antibody TA-2 and the small molecule inhibitor BIO5192 [2(S)-[[1-(3,5-dichloro-benzenesulfonyl)-pyrrolidine-2(S)-carbonyl]-amino]-4-[4-methyl-2(S)-(methyl-[2-[4-(3-o-tolyl-ureido)-phenyl]-acetyl]-amino)-pentanoylamino]-butyric acid]. TA-2 has been extensively studied in rats and provides a benchmark for assessing function. BIO5192 is a highly selective and potent (KD of

Since 1999, government guidance in child protection has been issued which embodies a shift in practice and philosophy, sometimes expressed in the word ‘refocusing’. School staff have never found child protection easy, but these shifts in policy and practice put particular demands on them. Steve Adams identifies these demands and the ways in which they differ from previous child protection expectations on schools. He sees real problems for schools in the new guidance, but also suggests ways in which they may work positively with at least some of the changes.

The ideas of quantum mechanics are challenging for students. The quantum bomb thought experiment described here shows how the existence of other possible worlds can affect outcomes in the real world as a result of quantum interference.

We have used chemical cross-linking to identify sequences in integrin alpha4beta1 that are involved in its interactions with ligands. A recently described leucine-aspartic acid-valine (LDV)-based small molecule inhibitor of alpha4beta1 (BIO-1494), that contained a single reactive amino group for targeting the cross-linking, was used for these studies. The specificity of the interaction was defined by (i) the ability to block the interaction with a competitive inhibitor lacking the reactive group, (ii) the absolute requirement of divalent cations for cross-linking, and (iii) the lack of cross-linking to the functionally related integrin alpha4beta7. With ANB-NOS as the cross-linker, only the beta1 chain was labeled with BIO-1494, while with the more flexible cross-linker DSS both the alpha4 and beta1 chains were modified. Similar results were obtained when cross-linking was performed on K562 cells expressing alpha4beta1 but not on K562 cells expressing alpha2beta1. The site of cross-linking on the beta1 chain was localized by CNBr peptide mapping within residues 130-146, a region that contains the putative metal binding site DXSXS and for which analogous data had been generated with RGD binding to integrin alphaIIbbeta3. The striking similarity between the data we generated for an LDV ligand and published data for the RGD family supports the notion of a common ligand binding pocket formed by both integrin chains. The cross-linking strategy developed here should serve as a useful tool for studying alpha4beta1 function.

To prepare students for the 21st century, educators must reexamine their educational paradigms and look far into the future. An Information Age audit might be a good way to start.

(1990). Child Self-protection: Concerns About Classroom Approaches. Pastoral Care in Education: Vol. 8, No. 3, pp. 3-6.

Asthma, a chronic inflammatory disease of the airways, is a significant burden on our healthcare system. There is high unmet need for treatments directed towards the underlying causes of the disease. The cell surface integrin VLA-4 (very late antigen-4; alpha4beta1; CD49d/CD29) plays an important role in the trafficking of white blood cells to sites of inflammation and represents an exciting target for the development of novel anti-inflammatory drugs for the treatment of asthma. Here, we review our efforts to use rational design to identify potent, selective inhibitors of VLA-4. We describe the discovery of a series of potent VLA-4 inhibitors through the addition of a novel N-terminal organic cap to a tetrapeptide VLA-4 binding motif 4-((N'-2-methylphenyl)uriedo)phenylacetyl-Leu-Asp-Val-Pro ; Kd = 70 pM), and rationalize their structure-activity relationships using 3D-QSAR. Also, we show our rational peptidomimetic design strategy using "template hopping" from the gpIIb/IIIa integrin antagonist field, and also a novel virtual screening strategy. Two series have been developed, one that has high selectivity for the activated over the non-activated state of the receptor, and the other which is non-selective inhibiting both activated and non-activated VLA-4. Both series are highly selective for VLA-4 versus against other integrin family members. These inhibitors show promise in the treatment of asthma, based upon efficacy in a sheep model of asthma, where they inhibit both the early and late-phase responses to asthma and also block hypersensitivity.

Integrin alpha4beta1 mediates leukocyte recruitment, activation, mediator release, and apoptosis inhibition, and it plays a central role in inflammatory pathophysiology. High-affinity, selective inhibitors of alpha4beta1, based on the Leu-Asp-Val (LDV) sequence from the alternatively spliced connecting segment-1 (CS-1) peptide of cellular fibronectin, are described that employ a novel N-terminal peptide "cap" strategy. One inhibitor, BIO-1211, was approximately 10(6)-fold more potent than the starting peptide and exhibited tight-binding properties (koff = 1.4 x 10(-4) s-1, KD = 70 pM), a remarkable finding for a noncovalent, small-molecule inhibitor of a protein receptor. BIO-1211 was also 200-fold selective for the activated form of alpha4beta1, and it stimulated expression of ligand-induced epitopes on the integrin beta1 subunit, a property consistent with occupancy of the receptor's ligand-binding site. Pretreatment of allergic sheep with a 3-mg nebulized dose of BIO-1211 inhibited early and late airway responses following antigen challenge and prevented development of nonspecific airway hyperresponsiveness to carbachol. These results show that highly selective and potent small-molecule antagonists can be identified to integrins with primary specificity for peptide domains other than Arg-Gly-Asp (RGD); they confirm the generality of integrins as small molecule targets; and they validate alpha4beta1 as a therapeutic target for asthma.

Boltzmann is one of the most interesting of the late nineteenth century physicists and is without doubt one of the most important. His work in kinetic theory and statistical thermodynamics laid the foundations for many of the major developments of twentieth century physics and it is a great pity that there are few English language biographies. Carlo Cercignani is Professor of Theoretical Mechanics at the Politecnico di Milano and is well equipped to describe and comment upon Boltzmann's theories - his own research includes applications of the Boltzmann equation. This book is published by OUP and reminds me of Abraham Pais's excellent scientific biographies of Bohr and Einstein (also OUP). In fact I suspect the intention was to conform to the style and standards set by those books. To this end Boltzmann's physics is the centrepiece of the story and subtle technical details are discussed in the main body of the text (albeit with a minimum of mathematics). However, there are substantial appendices in which some of the main results (e.g. the H-theorem) are derived. I am not convinced that this division has been entirely successful since the author seems so eager to get to grips with fine detail that the broad sweep of Boltzmann's ideas is not always clearly explained, and a reader lacking a foundation in statistical thermodynamics will struggle to follow the points being made. However, there is a great deal of interest here and the book is one I am sure I shall return to many times in the future. In fact it is probably more suited for reference than for reading - the author's English style is often rather awkward and some passages are a struggle, but the content and organization are good and there is plenty of exciting physics. The main part of the book begins with a short biography, but the next eight chapters deal with different aspects of his physics. The final chapters discuss his philosophy, his contemporaries and the influence of his ideas on twentieth century developments. There is an amusing postscript which is a translation of Boltzmann's own account of a trip to California: 'A German Professor's Journey into Eldorado'. I couldn't help feeling that the light-hearted self-aware character who wrote this funny little travel story seemed totally different from the character I had been reading about in the rest of the book. But then Boltzmann's suicide in Duino in 1906 also jars and it is obvious that we are dealing with a complex and multi-faceted man, a genius with just a touch of paranoia who was prone to bouts of deep depression. For the reader who has studied statistical mechanics the arguments about irreversibilty and the status of the H-theorem and the second law are fascinating. The comparison of Boltzmann and Gibbs (who gave a more generalized version of some of Boltzmann's results and whose work seems to have been accepted much more rapidly than Boltzmann's) is also interesting. The arguments with Mach and the energeticists are well known but worth reviewing - it is hard to believe that scientists and philosophers can fight so passionately over the status of their ideas; it perhaps helps to explain why so many Austrian intellectuals of that era took their own lives. In fact it has been suggested that the conflict about atoms (whether they are real, as Boltzmann seems to have believed, or merely abstract mathematical models, as claimed by Oswald and Mach) was one of the pressures that drove Boltzmann over the edge in 1906. However, what I found most interesting was reading about the way Boltzmann dealt with continuous energy distributions by introducing a mathematical process of quantization in order to derive his main results. This technique was adopted and adapted by Planck in order to derive the famous formula for the spectrum of black-body radiation, and by Einstein for the photon theory of light. In fact the development of quantum theory seems to have relied on methods first used by Boltzmann some 20 years earlier. This link is explained very clearly. I was also surprised to learn that Boltmann's philosophy of science pre-empted the ideas of Thomas Kuhn, and the author quotes a number of passages that make some of Kuhn's work sound like plagiarism! It is ironic that, as Boltzmann lost hope and hanged himself, Einstein had already published a paper on Brownian motion that established the reality of atoms - the energeticists were about to concede defeat. Boltzmann's discoveries and speculations are startlingly modern and he is without doubt one of the pioneers of the twentieth century revolution in physics. As we approach the twenty-first century this book will go some way toward cementing that reputation.

Situational Awareness (SA) is critical to maintain aimraft safety. To verify the SA associated with aircraft symbology, a procedure was developed and has been included in MIL-STD1787C. The procedure i,s based on a decision tree for selecting the SA measure that is most appropriate under the test conditions. The procedure and a review of the recommended measures of SA are included in this paper The recommended measures include: China Lake SA (CLSA), Crew Situational Awareness (CSA), the Situational Awareness Global Assessment Technique (SAGAT), Situational Awareness Probe (SAP), Situational Awareness Rating Technique (SART), Situational Awareness Supervisory Rating Form (SASRF), and the Situational Awareness Subjective Workload Dominance (SA SWORD). This review includes: a general description of each measure; a discussion of its strengths and limitations; its requirements for data collection, reduction, and analysis; and sources of further information.

This is one of eight student guides for the SLIPP course (Supported Learning in Physics Project) and is intended for semi-independent study by post-16 students preparing for A-level, AS-level and GNVQ science and engineering. In common with other books in this series it uses student-centred experiments set in important everyday contexts to teach basic principles. The central idea in the SLIPP scheme is that students can study on their own or in small groups at a pace that suits them under the general guidance of a class or individual tutor. Following a brief introduction the four main chapters lead students through: flow in a central heating system; moving fluids through pipes; laminar and turbulent flow; and flow in open channels. Each chapter opens with a 'Ready to Study Test', contains a fair amount of theory, a large number of suggested investigations and activities, plenty of good questions with clear detailed answers, a checklist of achievements and a glossary. On completing the unit there is a separate 'Exit Test' administered via tutors (but unavailable to me as I write this review). This was my first direct contact with the SLIPP scheme, and if all the units contain as many good ideas as this one I will be purchasing the entire set of books and stealing various investigations to fit into my normal teaching. In this respect the book is an excellent departmental resource and something that can be passed to particular students either to extend their experience or to support their own project work. I was particularly pleased by the wide range of approaches to the measurement of flow rates and the clear experimental guidance provided for the investigations. There is a freshness about this approach which is very appealing, but there are also some serious drawbacks with this book, particularly when it is considered as a student guide. In many places I felt the organization was poor and would confuse the student. New ideas are mentioned and left floating (e.g. the mention of a gas meter on p 22 implies that we are about to find out how one works, but it doesn't reappear), or questions are asked before the relevant theory has been covered (e.g. in the section on pp 85 - 87 concerning the Pitot static tube - how can students answer Q27 and Q28 before they read the theory that follows them?). The authors also seemed uncomfortable mixing theory (e.g. electromagnetic induction or the Hall effect) with experiments, and the two do not fit easily together - I think they needed clearer segregation. They also wanted to give some historical background and human interest, so there are little vignettes on Faraday or Boltzmann but again these may confuse the student (e.g. between pp 54 and 56 we meet balanced and unbalanced Wheatstone bridges, feedback loops, a differential amplifier, a biography of Wheastone, some vaguely relevant but superficial comments about the invention of telegraphy, Chladni plates and semiconductors...!). The level is also rather variable, with a considerable mathematical competence assumed for the theory and data processing whilst there is an implication that the book will still be of use for weaker students. I am not convinced this will be the case. I also found the placing and labelling of figures a problem, often having to think quite hard to work out what they showed or why they were relevant (the circuit diagram on p 54 will mean very little to the vast majority of students - it involves two separate feedback circuits, neither of which is explained). I should also mention a major error in physics that appears in the important section on the Hall effect: magnetic and electric fields seem to have been confused on p 32, so that the explanation and derivation of the Hall voltage are nonsense). Overall I think this book is seriously flawed in its organization and would have benefited from more careful checking and trialling. This is a great pity because the content, as I have already said, is interesting and exciting, and a good student who can carefully pick his or her way through it would learn a lot from the experience, not least the hands-on feel of 'real' scientific investigation. It will still be useful for teachers and bright students, but I suspect most of its intended users will find significant parts of it hard going.

The authors begin their prologue with the pertinent question, `Does the world really need another book about Richard Feynman'. My immediate response was `No' because Mehra ( The Beat of a Different Drum) has given a biography for the physicist, Gleick ( Genius) has given a detailed general biography accessible to the interested layperson, and Feynman himself has given an insight to his mischievous and precocious pranks with his two volumes of anecdotes ( Surely You're Joking, Mr Feynman! and What Do You Care What Other People Think?), a gentle but accurate introduction to his science and philosophy in QED and The Character of Physical Law and, of course, the wonderful three-volume set of Lectures on Physics. There are others too, but these stand out. Unlike Feynman's approach to physics, which allowed for all possible histories to contribute to the final process, this book traces a single history in strict chronological order. It is very conventional. It also seemed very familiar; there were very few stories about Feynman I had not read before, and here they are retold rather than reinterpreted, the early chapters in particular seeming to rely heavily on Mehra's book, the later ones drawing more widely but reiterating many of Feynman's own anecdotes. Alongside the biography there are some clear and concise explanations of the physics. These are generally very good indeed. I thought the discussion of the absorber theory, developed by Wheeler and Feynman in the 1940s, was particularly well done, and the final chapter, on `Physics after Feynman', really did give a feel for the impact of this man's work on physics at the most fundamental and universal level. There are a few black and white photographs of Feynman in the centre of the book and a couple of sketches elsewhere (including, of course, some Feynman diagrams) but I was disappointed not to see a picture of the famous Feynman van (especially since the author made a pilgrimmage to see it while in Pasadena). Each chapter ends with a list of references and there is a short bibliography at the end of the book. In some ways I was disappointed with the book. It added nothing to my knowledge of Feynman, and little to my appreciation of his work. Feynman is certainly one of my heroes in physics, and this book was an excuse for some hero worship, which is in its own way fine, but I don't think it really got under the skin of the man. It is certainly well written, an easy and enjoyable read, but it takes all existing stories at face value and is totally uncritical. It does capture the excitement and adventure of A Life in Science (its subtitle) and is the sort of book to fire up the imagination of a sixth-former who has heard something about this eccentric genius and wants to learn a little more, but if you've read the books listed earlier you will find nothing new here. Having said that, I must of course add that I devoured the book in three days, and if you are looking for an easy diversion to remind you what a wonderful physicist Feynman was, then this can be enjoyed like easy-listening music.

Einstein's Mirror is a companion to the authors' highly successful book, The Quantum Universe. In it Hey and Walters have adopted a similar approach with the clear intention of providing a broadly accessible survey of relativistic physics. The book is well illustrated with photographs and line drawings and covers the development, experimental tests and implications of both the special and general theories. The book divides roughly into three parts: the first four chapters deal with the relativity of space-time and motion (time dilation, length contraction, velocity addition etc); the next three explore the consequences of mass - energy equivalence (E = mc2, fission and fusion etc) with a lengthy digression on how Dirac's relativistic quantum theory of the electron led to the prediction of antimatter and the theoretical description of spin; and the next three chapters discuss the equivalence principle, the development of general relativity and its implications for cosmology. There is also a final chapter on 'Relativity and Science Fiction' which is interesting, but to my mind slightly uncomfortable in the context of the rest of the book. The appendix includes simple derivations of time dilation, velocity addition and mass increase with velocity and there is also a chronology and useful glossary. This book differs from The Quantum Universe in two major ways: whereas quantum theory was developed by the pantheon of twentieth century physicists, relativity (especially the general theory) was created almost single-handedly by Einstein; and where quantum theory is directly relevant to our everyday lives through electronic technology, relativity has few applications outside the rather esoteric worlds of particle physics and cosmology. Einstein's central role means that the book is partly biographical although every opportunity is taken to link Einstein's own ideas to those of his predecessors and contemporaries. This works well, although sometimes the historical context is developed to such an extent that you could forget you are reading a book about relativity. The chapter on E = mc2, for example, begins by discussing caloric, phlogiston and the early development of thermodynamics before considering mass - energy equivalence through an interesting thought experiment that is analysed more carefully in the appendix. The lack of everyday examples of relativistic effects is more of a problem because it was the emphasis on applications that helped distinguish The Quantum Universe from other popular books about quantum mechanics. For this reason Einstein's Mirror is not so distinct, reminding me of earlier books like Einstein's Universe by Nigel Calder, although it is better illustrated and includes an excellent selection of quotes and anecdotes. There are also some informative 'boxes' explaining particular topics such as the Michelson - Morley experiment, the Global Positioning System and radio astronomy. Most of the quotes used were already familiar but it is good to see so many of the best ones collected here. The book is aimed at final-year students in school, undergraduates in science subjects and general readers with an interest in science, and it is certainly accessible to them. It is well-paced, logically structured and an easy and interesting read, although there are a few passages where rather a lot is assumed on behalf of the reader - for example, I doubt whether the following passage, about the Higgs mechanism, will mean a great deal to most sixth formers: 'The key to understanding these interactions was a symmetry known as 'gauge invariance'. A better name for this symmetry would be 'phase invariance', since the symmetry arises because of the freedom for all the matter fields in these theories to be multiplied by an arbitrary space-time dependent phase with no change in the resulting physics.' Einstein's Mirror gives an excellent background to Einstein's life and ideas, and special and general relativity are set in a human and historical context. It will certainly appeal to its intended readers but will be of most value to those who already have some idea about the concepts involved.

Jim Breithaupt's A-level text has been substantially revised and developed to cover all the essential physics in the A-level core and in several of the more popular options (especially materials, astronomy, turning points and particle physics). It also includes useful subsections on electronics and communications. The book is organized into six major sections (mechanics, materials, fields, waves, electricity and inside the atom) and special topics and applications enter naturally in the context of relevant basic ideas. In addition there is a useful final section on skills in physics including essential mathematics, laboratory practice and communications skills. There is a large bank of questions (with numerical answers) arranged into `short questions' at the end of each topic and extra multiple choice and long questions at the end of each of the major sections. There are also some comprehension exercises. The book's main aim is to take students from GCSE to A-level but is also suitable for AS-level, GNVQ, IB and Scottish Highers and SYS examinations. There is a companion volume, `Explaining Physics at A-Level', whlch deals with more of the optional topics and gives a more detailed treatment of key compulsory topics `for those aiming at the top grade'. Having said this, I feel that the level of treatment in this book would be no impediment to the ambitions of these `high-achievers' and would be a useful stand-alone textbook for mixed ability A-level classes. The presentation is attractive, with full colour used throughout and the text supported by many cartoons and sketches and some photographs. Equations are highlighted and there are helpful summaries at the end of each topic. There is a great deal of information in the book and the price is that the text is densely packed with little space on the page; this could be a problem for weaker students. Also, the pace within each topic is rather unrelenting, and although the text is divided into subsections there is little room for alternative explanations and analogies - often new material is presented in a clear but rather matter-of-fact way that runs straight into algebraic or numerical examples. I would also have preferred to see the many experimental examples segregated from the main text so that they can be found more easily or skipped if not required. One advantage of the dense format and the use of thin pages is that this 550 page book is considerably more portable than many of its competitors which do not attempt to include optional material. It is certainly an option worth considering, either as a general reference to be kept at home, or as a text to use alongside experimental work in class, and it seems good value for money.

Critically ill hospital patients were fed enteral formulas containing different fat substrates. Seven patients received formula X, which contained 28 g of structured triglycerides and menhaden oil to provide 7.6 g of medium-chain fatty acids, 2.5 g linoleic acid, 1.3 g eicosapentaenoic acid, and 0.4 g docosahexaenoic acid per 1000 mL of formula. Six patients received formula Y consisting of 36.8 g of medium-chain triglycerides and corn and soy oils providing 14.3 g medium-chain fatty acids and 11.7 g linoleic acid per 1000 mL. Feeding of formula X increased plasma total phospholipid levels of eicosapentaenoic acid on days 7 and 14 and docosahexaenoic acid levels on day 14. Plasma levels of linoleic acid were reduced in formula-X-fed in comparison to formula-Y-fed patients, whereas arachidonic acid was maintained in both groups during feeding. As a result of these changes, the patients receiving formula X had decreased ratios of arachidonic acid:eicosapentaenoic acid in plasma. Formula Y feeding did not alter eicosapentaenoic acid and docosahexaenoic acid levels in the plasma. In the erythrocyte, formula X feeding resulted in a threefold increase in eicosapentaenoic acid from mean baseline levels of 0.4 +/- 0.4% to a mean value of 1.2 +/- 0.9% at day 7. The formula X feeding decreased linoleic acid levels on days 7 and 14, whereas levels of arachidonic acid and docosahexaenoic acid remained constant. Formula Y feeding did not affect any of the parameters measured for erythrocytes.(ABSTRACT TRUNCATED AT 250 WORDS)

Westminster School, London, UK A few weeks ago David Thomson, J J Thomson's grandson, presented a Friday evening discourse at the Royal Institution. In it he traced the development of JJT's life from his early studies at Owen's College in Manchester, on to Trinity College Cambridge, his work under Rayleigh at the Cavendish, and his succession as Professor of Experimental Physics in 1884 (a post he passed on to Rutherford in 1919). These were years of heroic discoveries that shaped 20th century physics. Looking around the lecture theatre at all the bow-ties and dinner jackets, it must have been rather similar on 30 April 1897 when JJT delivered his famous discourse on 'Cathode Rays' in which he cautiously but confidently announced that his own results together with those of other experimenters (Lenard in particular): `....seem to favour the hypothesis that the carriers of the charges are smaller than the atoms of hydrogen.' In this issue articles by Leif Gerward and Christopher Cousins, and by Isobel Falconer explore the historical and philosophical context of that discovery. The sound-bites to history in many A-level courses have JJT as both the hero who single-handedly discovered the electron and the rather naive Victorian scientist who thought the atom was a plum pudding. It is valuable to see how Thomson's work pulled the threads of many experiments together and to realize that he may have been first to the post because of a difference in the philosophical approach to cathode rays in Britain compared to Europe. Experimental data must always be interpreted, and divergent philosophies can lead to quite different conclusions. The electron was, of course, the first subatomic particle to be identified. Christine Sutton's article looks at how 20th century discoveries reveal Nature's mysterious habit of repeating successful patterns---electrons for example have very close relations, the muon and the tau---but why? Perhaps the answer will come from the theoreticians. One of the greatest of these was Paul Dirac, a marvellously reticent man with an eye for mathematical beauty. David Miller, one of the winners of William Waldegrave's 'Higgs Challenge' in 1993, shows how Dirac constructed his famous equation, and how it describes the behaviour of the electron and its neutrino and led to the prediction of antimatter and the explanation of spin. He draws an interesting parallel between Dirac's negative energy electrons and the contemporary development of solid state physics. G P Thomson, JJ's son, also got in on the act: father got the Nobel Prize (1906) for showing the electron is a particle and son (1937) won it for showing it also behaves like a wave! This has had a profound impact both on the interpretation and experimental testing of quantum theory and in the way we use electrons. Electron waves are essential to understand solid state physics and wave-like properties are fundamental to the behaviour of many electronic devices. But it is not just in physics and electronics that the electron has been revolutionary, and John Squire's article reviews the use of the electron microscope in biology. Having crossed the border into biology (as so many physicists have done this century) it should be pointed out that electron physics also caused a paradigm shift in chemistry. Electronic structure made the Periodic Table comprehensible and led to a theory of bonding that accounts for the mechanical, electrical and optical properties of many materials. This is described in Peter Hughes's article. Which brings me back to JJT and those sound-bites, and the Royal Institution for that matter.... On 10 March 1905 JJT gave another of his Friday Evening Discourses. This one was called 'The Structure of the Atom'. In it he developed a model suggested by Lord Kelvin, in which negative corpuscles arrange themselves in a stable configuration within a sphere of positively charged fluid. This is the infamous `plum pudding'. There is not room to go into detail here, but he showed mathematically and using a 2D magnetic model that the electrons would arrange themselves in a series of shells which he identified with the periods in the Periodic Table and linked to reactivity. He discussed electronegativity and showed how it would increase along each period (as it does). He suggested transmutation of the elements by a rearrangement of the positive fluid and even considered electrostatic conditions which might result in fission or fusion (remember, this is long before the alpha scattering experiments of Geiger and Marsden). Even covalent and ionic bonding and crystalline structures were included, with atomic valence directions corresponding to lines of symmetry in the electron arrangement inside the atom. It is a shame that the `plum pudding model' gets such shabby treatment, and perhaps a comment on the distorted view of the history of physics we pass on to our students by ignoring the context and background to important discoveries.

The modification of the terminal ionizable charges of an immunogenic peptide, HEL (46-61), was found to greatly increase the immunogenicity of the peptide. The modified peptide had 100- to 1000-fold enhanced activity in both in vitro and in vivo T cell assays. The mechanism of the enhancement was investigated by determining the binding affinities to I-Ak as well as circular dichroism (CD) studies. The native and enhanced peptides had indistinguishable binding affinities, as well as similar kinetics. The CD studies revealed that in aqueous solution, neither peptide had any detectable helicity; however, the addition of trifluoroethanol did result in significant helicity; with the two peptides being indistinguishable. These same modifications were also shown to enhance other immunogenic peptides if they contained a basic carboxy-terminal amino acid residue. Thus, by modifying the termini of T cell epitopes, their immunogenicity can be dramatically increased, but the molecular basis for this enhancement is still unclear.