bluuebunny/crossref_metadata_2025 huggingface dataset:
Climate Changes during the Holocene and their Impact on Hydrological Systems
Authors: Issar Arie S.
Published: December 2009

It is now widely accepted that increasing concentrations of greenhouse gases in the atmosphere are causing higher global atmospheric temperatures. However, there is still a great deal of uncertainty about the likely effects of such a temperature rise on climate, and even more about the impacts of climate change and variability on the world's hydrological regimes and socio-economic systems. Studying the effects of climate variability in the past can give clues as to possible future effects. This volume provides a comprehensive review of the effects of climate variability on hydrological and human systems in the Holocene (the last 10,000 years), in various parts of the world. The book concentrates on the regions bordering the Mediterranean Sea, western and central Europe, China, Japan, West and South Africa and the southwestern USA. This book will be of value to researchers and professionals in hydrology, climatology, geology and historical geography.
The Potential Distribution Theorem and Models of Molecular Solutions
Authors: Beck Tom L. , Paulaitis Michael E. , Pratt Lawrence R.
Published: December 2009

An understanding of statistical thermodynamic molecular theory is fundamental to the appreciation of molecular solutions. This complex subject has been simplified by the authors with down-to-earth presentations of molecular theory. Using the potential distribution theorem (PDT) as the basis, the text provides a discussion of practical theories in conjunction with simulation results. The authors discuss the field in a concise and simple manner, illustrating the text with useful models of solution thermodynamics and numerous exercises. Modern quasi-chemical theories that permit statistical thermodynamic properties to be studied on the basis of electronic structure calculations are given extended development, as is the testing of those theoretical results with ab initio molecular dynamics simulations. The book is intended for students taking up research problems of molecular science in chemistry, chemical engineering, biochemistry, pharmaceutical chemistry, nanotechnology and biotechnology.
Essentials of UMTS
Authors: Cox Christopher
Published: December 2009

The third generation (3G) cellular system UMTS is advanced, optimised and complex. The many existing books on UMTS attempt to explain all the intricacies of the system and as a result are large and equally complex. This book takes a different approach and explains UMTS in a concise, clear and readily understandable style. Written by a professional technical trainer, and based on training courses delivered on UMTS to telecommunication companies worldwide, Essentials of UMTS will enable you to grasp the key concepts quickly. It assumes no previous knowledge of mobile telecommunication theory, and is structured around the operation of the system, clearly setting out how the different components interact with each other, and how the system as a whole behaves. Engineers, project managers and marketing executives working for equipment manufacturers and network operators will find this concise guide to UMTS invaluable.
Next Generation Wireless LANs
Authors: Perahia Eldad , Stacey Robert
Published: December 2009

If you've been searching for a way to get up to speed quickly on IEEE 802.11n without having to wade through the entire standard, then look no further. This comprehensive overview describes the underlying principles, implementation details, and key enhancing features of 802.11n. A detailed discussion of the key throughput, robustness, and reliability enhancing features (such as MIMO, 40 MHz channels, and packet aggregation) is given, in addition to a clear summary of the issues surrounding legacy interoperability and coexistence. Advanced topics such as beamforming and fast link adaption are also covered. With numerous MAC and physical layer examples and simulation results included to highlight the benefits of the new features, this is an ideal reference for designers of WLAN equipment, and network managers whose systems adopt the new standard. It is also a useful distillation of 802.11n technology for graduate students and researchers in the field of wireless communication.
MicroRNAs
Authors: Altman Sidney , Ambros Victor R.
Published: December 2009

MicroRNAs (miRNAs) are RNA molecules, conserved by evolution, that regulate gene expressions and their discovery has revolutionised both basic biomedical research and drug discovery. Expression levels of MiRNAs have been found to vary between tissues and with developmental stages and hence evaluation of the global expression of miRNAs potentially provides opportunities to identify regulatory points for many different biological processes. This wide-ranging 2007 reference work, written by leading experts from both academia and industry, will be an invaluable resource for all those wishing to use miRNA techniques in their own research, from graduate students, post-docs and researchers in academia to those working in R&D in biotechnology and pharmaceutical companies who need to understand this emerging technology. From the discovery of miRNAs and their functions to their detection and role in disease biology, this volume uniquely integrates the basic science with industry application towards drug validation, diagnostic and therapeutic development.
The Ecology of Phytoplankton
Authors: Reynolds C. S.
Published: December 2009

Communities of microscopic plant life, or phytoplankton, dominate the Earth's aquatic ecosystems. This important new book by Colin Reynolds covers the adaptations, physiology and population dynamics of phytoplankton communities in lakes and rivers and oceans. It provides basic information on composition, morphology and physiology of the main phyletic groups represented in marine and freshwater systems and in addition reviews recent advances in community ecology, developing an appreciation of assembly processes, co-existence and competition, disturbance and diversity. Although focussed on one group of organisms, the book develops many concepts relevant to ecology in the broadest sense, and as such will appeal to graduate students and researchers in ecology, limnology and oceanography.
Human Biology of Afro-Caribbean Populations
Authors: Madrigal Lorena
Published: December 2009

A comprehensive study of the microevolution of Caribbean populations of African descent, this 2006 book reviews the conditions endured by the slaves during their passage and in the plantations and how these conditions may have affected their own health and that of their descendants. Providing an evolutionary framework for understanding the epidemiology of common modern-day diseases such as obesity, hypertension and diabetes, it also looks at infectious diseases and their effect on the genetic make-up of Afro-Caribbean populations. Also covered are population genetics studies that have been used to understand the microevolutionary pathways for various populations, and demographic characteristics including the relationships between migration, family type and fertility. Ending with a case study of the Afro-Caribbean population of Limón, Costa Rica, this book is an essential resource for researchers working in biological anthropology, demography, and epidemiology, and for those interested in the African diaspora in the New World.
The Cube-A Window to Convex and Discrete Geometry
Authors: Zong Chuanming
Published: December 2009

This tract has two purposes: to show what is known about the n-dimensional unit cubes and to demonstrate how Analysis, Algebra, Combinatorics, Graph Theory, Hyperbolic Geometry, Number Theory, can be applied to the study of them. The unit cubes, from any point of view, are among the most important and fascinating objects in an n-dimensional Euclidean space. However, our knowledge about them is still quite limited and many basic problems remain unsolved. In this Tract eight topics about the unit cubes are introduced: cross sections, projections, inscribed simplices, triangulations, 0/1 polytopes, Minkowski's conjecture, Furtwangler's conjecture, and Keller's conjecture. In particular the author demonstrates how deep analysis like log concave measure and the Brascamp-Lieb inequality can deal with the cross section problem, how Hyperbolic Geometry helps with the triangulation problem, how group rings can deal with Minkowski's conjecture and Furtwangler's conjecture, and how Graph Theory handles Keller's conjecture.
Theory of Remote Image Formation
Authors: Blahut Richard E.
Published: December 2009

This book was first published in 2004. In many applications, images, such as ultrasonic or X-ray signals, are recorded and then analyzed with digital or optical processors in order to extract information. Such processing requires the development of algorithms of great precision and sophistication. This book presents a unified treatment of the mathematical methods that underpin the various algorithms used in remote image formation. The author begins with a review of transform and filter theory. He then discusses two- and three-dimensional Fourier transform theory, the ambiguity function, image construction and reconstruction, tomography, baseband surveillance systems, and passive systems (where the signal source might be an earthquake or a galaxy). Information-theoretic methods in image formation are also covered, as are phase errors and phase noise. Throughout the book, practical applications illustrate theoretical concepts, and there are many homework problems. The book is aimed at graduate students of electrical engineering and computer science, and practitioners in industry.
Satisficing Games and Decision Making
Authors: Stirling Wynn C.
Published: December 2009

In our day-to-day lives we constantly make decisions which are simply 'good enough' rather than optimal. Most computer-based decision-making algorithms, on the other hand, doggedly seek only the optimal solution based on rigid criteria and reject any others. In this book, Professor Stirling outlines an alternative approach, using novel algorithms and techniques which can be used to find satisficing solutions. Building on traditional decision and game theory, these techniques allow decision-making systems to cope with more subtle situations where self and group interests conflict, perfect solutions can't be found and human issues need to be taken into account - in short, more closely modelling the way humans make decisions. The book will therefore be of great interest to engineers, computer scientists and mathematicians working on artificial intelligence and expert systems.
The Clinical Neuropsychiatry of Stroke
Authors: Robinson Robert G.
Published: December 2009

This second edition, published in 2006, covers the range of neuropsychiatric syndromes associated with stroke, including cognitive, emotional and behavioural disorders such as depression, anxiety and psychosis. There is growing recognition among a wide range of clinicians and allied healthcare staff that post-stroke neuropsychiatric syndromes are common and serious. Such complications can have a negative impact on recovery and even survival; however, there is now evidence suggesting that pre-emptive therapeutic intervention in high-risk patient groups can prevent the initial onset of the conditions. This opportunity for primary prevention marks a huge advance in the management of this patient population.
Neonatal Nutrition and Metabolism
Authors: Thureen Patti J.
Published: December 2009

Neonatal nutrition has a pivotal role in normal child development and is of even greater importance in the sick or premature neonate. This 2006 edition includes a comprehensive account of the basic science, metabolism and nutritional requirements of the neonate, and a greatly expanded number of chapters dealing in depth with clinical issues ranging from IUGR, intravenous feeding, nutritional therapies for inborn errors of metabolism, and care of the neonatal surgical patient. Evolving from these scientific and clinical aspects, the volume highlights the important long-term effects of fetal and neonatal growth on health in later life. In addition, there are very practical chapters on methods and techniques for assessing nutritional status, body composition, and evaluating metabolic function.
Viva Tutorials for Surgeons in Training
Authors: Adams Wendy , Bull Jonathan , Epstein Jonathan , Krishnan Anant , Menezes Leon , Modarai Bijan , Patterson Paul , Sahai Arun , Schizas Alexis
Published: December 2009

This book is designed specifically for candidates preparing for the MRCS Viva examination. The format of the exam has been used in the book's structure, with over 1000 questions to illustrate the key points of over 200 topics. The book has been divided into 6 main chapters corresponding to a viva 'station' in the exam. Each chapter begins with a check-list of the main topics and themes covered by the exam, and information is then subdivided logically within the chapter itself. Key 'pass-or-fail' concepts are covered, and in some cases, topics are covered in more detail than will be asked in the exam, so the candidate can be confident that they will be fully prepared.
Solar and Stellar Magnetic Activity
Authors: Schrijver C. J. , Zwaan C.
Published: December 2009

This timely volume provides the first comprehensive review and synthesis of current understanding of magnetic fields in the Sun and similar stars. Magnetic activity results in a wealth of phenomena - including starspots, non-radiatively heated outer atmospheres, activity cycles, deceleration of rotation rates, and even, in close binaries, stellar cannibalism - all of which are covered clearly and authoritatively. This book brings together for the first time recent results in solar studies and stellar studies. The result is an illuminating new view of stellar magnetic activity. Key topics include radiative transfer, convective simulations, dynamo theory, outer-atmospheric heating, stellar winds and angular momentum loss. Researchers are provided with a state-of-the-art review of this exciting field, and the pedagogical style and introductory material make the book an ideal and welcome introduction for graduate students.
Suspension Acoustics
Authors: Temkin Samuel
Published: December 2009

Originally published in 2005, this book is an introduction to the physics of suspensions of bubbles, droplets, and solid particles in both gases and fluids. Rather than treating each combination separately, a unified approach is used that permits most particle-fluid combination types to be discussed together. To do this, the book first presents a detailed discussion of the basic particle motions that small particles can sustain, paying particular attention to translations and pulsations, and to the thermal effects that occur as a result of those motions. The book then introduces the reader to the dynamics and thermodynamics of suspensions, with acoustic motions providing the main focus in the latter part of the book. The important acoustic problems of attenuation and dispersion are discussed from several fundamental perspectives. The book concludes with applications of acoustic techniques to the characterization and modification of suspensions by means of acoustic waves.
Origins of Life
Authors: Dyson Freeman
Published: December 2009

How did life on earth originate? Did replication or metabolism come first in the history of life? In this book, Freeman Dyson examines these questions and discusses the two main theories that try to explain how naturally occurring chemicals could organize themselves into living creatures. The majority view is that life began with replicating molecules, the precursors of modern genes. The minority belief is that random populations of molecules evolved metabolic activities before exact replication existed. Dyson analyzes both of these theories with reference to recent important discoveries by geologists and chemists. His main aim is to stimulate experiments that could help to decide which theory is correct. This second edition covers the enormous advances that have been made in biology and geology in the past and the impact they have had on our ideas about how life began. It is a clearly-written, fascinating book that will appeal to anyone interested in the origins of life.
Cerebrospinal fluid otorrhoea: a rare presentation of Langerhans' cell histiocytosis of the temporal bone
Authors: Vezina J-P , Audet N , Fradet G
Published: December 2009

Objective:

To report a case of Langerhans cell histiocytosis of the temporal bone presenting with cerebrospinal fluid fistula.

Patient:

A Caucasian woman presented to a tertiary care centre in Quebec, Canada, with a new onset of cerebrospinal fluid fistula. She had a significant destructive lesion of the temporal bone, and was diagnosed with Langerhans cell histiocytosis on biopsy.

Interventions:

The patient underwent surgical resection with reconstruction of the posterior fossa and tegmen. She suffered a relapse less than one year after surgery, and was finally treated with chemotherapy.

Main outcome and results:

The patient was free of disease at three-year follow up. No recurrence of the cerebrospinal fluid leak was observed after treatment.

Conclusion:

Langerhans cell histiocytosis of the temporal bone with intra-cranial involvement is rare in adults, with only two cases previously reported. Eleven paediatric cases have been reported. To our knowledge, this patient represents the first report of cerebrospinal fluid fistula as the initial presentation of the disease.
Immunity-mediated regulation of fecundity in the nematodeHeligmosomoides polygyrus– the potential role of mast cells
Authors: HASHIMOTO K. , UCHIKAWA R. , TEGOSHI T. , TAKEDA K. , YAMADA M. , ARIZONO N.
Published: December 2009

Previous studies have shown that host immunity regulates the fecundity of nematodes. The present study was aimed at clarifying the reversible nature of fecundity in response to changes of immunological status and to determine which effector cells are responsible for compromising fecundity inHeligmosomoides polygyrus. Enhanced fecundity was observed in immunocompromised SCID andnu/numice compared to those in the corresponding wild-type mice, with significantly fewer numbers of intrauterine eggs produced in the wild-type than in the immunodeficient mice. When 14-day-old adult worms from BALB/c mice were transplanted into naïve BALB/c mice, their fecundity increased significantly as early as 24 h post-transplantation, but not when they were transferred into immune mice, suggesting the plastic and reversible nature of fecundity in response to changes in host immunological status. In mast cell-deficientW/Wvmice, nematode fecundity was significantly higher than in mast cell-reconstitutedW/Wvor +/+ mice. The serum levels of the mast-cell protease mMCP1 were markedly increased in the wild-type as well as the mast cell-reconstitutedW/Wv, but not in theW/Wv, SCID, ornu/numice during infection. These findings raise the interesting possibility that certain activities of mast cells, either directly or indirectly, regulate parasite fecundity during infection.
The development of aspectual marking in child Mandarin Chinese
Authors: CHEN JIDONG , SHIRAI YASUHIRO
Published: December 2009

Cross-linguistic research on the development of tense-aspect marking has revealed a strong effect of lexical aspect. But the degree of this effect varies across languages. Explanation for this universal tendency and language-specific variation is still an open issue. This study investigates the early emergence and subsequent development of four grammatical aspect markers in Mandarin, -le(perfective),zai(progressive), -zhe(durative), and -guo(experiential), in the longitudinal speech data of four children acquiring Mandarin Chinese. It was found that the emergence of grammatical aspect marking generally follows the predictions of the aspect hypothesis, perfective -lepredominantly appearing with telic verbs, whereas progressivezaiis almost exclusively used with activity verbs. However, the typological features of Mandarin also affect the early uses of -le, which is used with stative predicates more frequently than predicted, and the input patterns play an important role in children's aspect marking. The results support a usage-based learning process in accord with a language-specific system of aspectual semantics, rather than a strong universal association of grammatical aspect and lexical aspect.
Death Is Just Not What It Used to Be
Authors: KIRKPATRICK JAMES N. , BEASLEY KARA D. , CAPLAN ARTHUR
Published: December 2009

It is said there are only two things in life that are certain: death and taxes … maybe only taxes.
Bioethics and Human Rights: Curb Your Enthusiasm
Authors: FENTON ELIZABETH , ARRAS JOHN D.
Published: December 2009

The call has been made for global bioethics. In an age of pandemics, international drug trials, and genetic technology, health has gone global, and bioethics must follow suit. George Annas is one among a number of thinkers to recommend that bioethics expand beyond its traditional domain of patient–physician interactions to encompass a broader range of health-related matters. Medicine, Annas argues, must “develop a global language and a global strategy that can help to improve the health of all of the world's citizens.” Individual countries cannot address global health issues, and culturally specific principles are inadequate for addressing global bioethics concerns. We will need a language and moral framework grounded in a foundation of universally shared, transcultural judgments about humankind that will also recognize moral pluralism. The claim has been made that such a foundation already exists in human rights, and that human rights should, therefore, be the new lingua franca of bioethics.
Moon meteoritic seismic hum: Steady state prediction
Authors: Lognonné Philippe , Le Feuvre Mathieu , Johnson Catherine L. , Weber Renee C.
Published: December 2009

We use three different statistical models describing the frequency of meteoroid impacts on Earth to estimate the seismic background noise due to impacts on the lunar surface. Because of diffraction, seismic events on the Moon are typically characterized by long codas, lasting 1 h or more. We find that the small but frequent impacts generate seismic signals whose codas overlap in time, resulting in a permanent seismic noise that we term the “lunar hum” by analogy with the Earth's continuous seismic background seismic hum. We find that the Apollo era impact detection rates and amplitudes are well explained by a model that parameterizes (1) the net seismic impulse due to the impactor and resulting ejecta and (2) the effects of diffraction and attenuation. The formulation permits the calculation of a composite waveform at any point on the Moon due to simulated impacts at any epicentral distance. The root‐mean‐square amplitude of this waveform yields a background noise level that is about 100 times lower than the resolution of the Apollo long‐period seismometers. At 2 s periods, this noise level is more than 1000 times lower than the low noise model prediction for Earth's microseismic noise. Sufficiently sensitive seismometers will allow the future detection of several impacts per day at body wave frequencies.
Chemically striking regions on Mars and Stealth revisited
Authors: Karunatillake Suniti , Wray James J. , Squyres Steven W. , Taylor G. Jeffrey , Gasnault Olivier , McLennan Scott M. , Boynton William , El Maarry M. R. , Dohm James M.
Published: December 2009

The Mars Odyssey Gamma Ray Spectrometer Suite has yielded global chemical information for Mars. In this work, we establish regions of unusual chemical composition relative to average Mars primarily on the basis of Ca, Cl, Fe, H, K, Si, and Th. Using data from Mars Odyssey; the Mars Exploration Rovers; the Mars Reconnaissance Orbiter Imaging; and 3.5 cm and 1.35 cm radar observations from Earth, we examine a chemically striking ≈2.E6 km2 region and find it to overlap significantly with a radar Stealth region on Mars. It is remarkably enriched in Cl and depleted in Fe and Si (along with minor variations in H, K, and Th) relative to average Mars. Surface dust observed at the two rover sites mixed with and indurated by Ca/Mg‐bearing sulfate salts would be a reasonable chemical and physical analog to meter‐scale depths. We describe potential scenarios that may have contributed to the unique properties of this region. The bulk dust component may be an air fall deposit of compositionally uniform dust as observed in situ. Hydrothermal acid fog reactions on the flanks of nearby volcanoes may have generated sulfates with subsequent deflation and transport. Alternatively, sulfates may have been produced by low‐temperature, regional‐scale activity of ground ice–driven brine and/or regional‐scale deposition of acidified H2O snowfall.
Introducing log‐kappa distributions for solar wind analysis
Authors: Leitner M. , Vörös Z. , Leubner M. P.
Published: December 2009

The one‐point probability density functions (PDFs) obtained from the Wind spacecraft observations of the magnitude of total magnetic field (B) and the solar wind quasi‐invariant (QI) are investigated at 1 AU during the years 1995 and 1998. It is known from previous studies that the distributions follow in a rather good approximation a lognormal distribution. This indicates that the underlying random multiplicative processes are skewed, the PDFs are nonsymmetric. The concept of kappa distributions generating PDF tails closer to the observed values is introduced. The skewness, characteristic for the multiplicative processes in the solar wind, is treated on the basis of log‐kappa distributions, introduced here for the first time. Normal and lognormal distributions are related in a similar way to each other as the kappa and log‐kappa distributions, although the statistics is based on extensive physics in the former and nonextensive physics in the latter cases. We show that log‐kappa PDFs describe the observed distributions in the solar wind more accurately than the lognormal PDFs. In particular, the tails of PDFs corresponding to extreme values of the considered parameters B and QI are better modeled in terms of the nonextensive approach. It indicates that, for the theoretical explanation of the complexity of multisource fluctuations present in 1 year solar wind magnetic and plasma data, both the extensive and the nonextensive physical description is needed. The variation of the values of kappa obtained from the log‐kappa fits can serve as a quantitative measure describing the changing balance between these two distinct physical processes during the solar cycle.
Delayed recovery of soil respiration after wetting of dry soil further reduces C losses from a Norway spruce forest soil
Authors: Muhr Jan , Borken Werner
Published: December 2009

This experiment investigated the effects of prolonged summer drought on soil respiration (SR) in a mountainous Norway spruce forest in south Germany. On three manipulation plots we excluded summer throughfall in the years of 2006/2007 and measured SR fluxes in comparison to three control plots. Using radiocarbon measurements we quantified the contribution of rhizosphere (RR) and heterotrophic respiration (HR) to total SR. In both manipulation years, mean CO2 emissions (±SE) from the throughfall exclusion (TE) plots were smaller than from the control plots with 5.7 t C ha−1 (±0.3) compared to 6.7 t C ha−1 (±0.2) in 2006 and 5.9 t C ha−1 (±0.3) compared to 7.0 t C ha−1 (±0.4) in 2007. Under control conditions, CO2 originated mainly from HR (60–95% of SR). Prolonged drought reduced HR, whereas RR was not affected or even increased slightly. Reduction of CO2 emissions on the TE plots was found up to 6 weeks after differences in matric potential conditions disappeared, possibly either because water repellency inhibited homogeneous rewetting of the organic horizons or because of severe damage to the microbial population. No evidence was found for the release of new, formerly protected substrates by preceding drought. Continuous measurements in 2008 (no manipulation) did not reveal increased CO2 emissions on the TE plots that could compensate for the reduction during the years 2006/2007. Based on our results, we postulate a negative feedback between increased frequency and magnitude of summer droughts and SR in Norway spruce stands.
Ambidextrous circular dichroism and circularly polarised luminescence from poly(9,9-di-n-decylfluorene) by terpene chirality transfer
Authors: Nakano Yoko , Liu Yang , Fujiki Michiya
Published: December 2009

Solvent chirality transfer using enantiomeric pairs of limonene andα-pinene allowed for the successful production of ambidextrous CD-/CPL-active polyfluorene aggregates from achiral polyfluorenes at 25 °C in a few minutes.
The influence of the antiferromagnetic boundary on the magnetic property of La2NiMnO6
Authors: Wang Xianjie , Sui Yu , Li Yao , Li Lu , Zhang Xingquan , Wang Yang , Liu Zhiguo , Su Wenhui , Tang Jinke
Published: December 2009

Polycrystalline La2NiMnO6 compounds were fabricated at different temperatures and their magnetic properties were investigated. Although the antiferromagnetic antisite disorder degree changes a little, the antiferromagnetic coupling intensity increases with increasing synthesized temperature. When La2NiMnO6 sample was cooled at 100 Oe from room temperature to 10 K, exchange bias was observed. Our results confirm that the exchange bias should originate from the coupling between the ferromagnetic La2NiMnO6 and antiferromagnetic antiphase boundaries.
On the asymptotic integration of a class of sublinear fractional differential equations
Authors: Băleanu Dumitru , Mustafa Octavian G.
Published: December 2009

We estimate the growth in time of the solutions to a class of nonlinear fractional differential equations D0+α(x−x0)=f(t,x) which includes D0+α(x−x0)=H(t)xλ with λ∊(0,1) for the case of slowly decaying coefficients H. The proof is based on the triple interpolation inequality on the real line and the growth estimate reads as x(t)=o(taα) when t→+∞ for 1>α>1−a>λ>0. Our result can be thought of as a noninteger counterpart of the classical Bihari asymptotic integration result for nonlinear ordinary differential equations. By a carefully designed example we show that in some circumstances such an estimate is optimal.
Volume of the set of unistochastic matrices of order 3 and the mean Jarlskog invariant
Authors: Dunkl Charles , Życzkowski Karol
Published: December 2009

A bistochastic matrix B of size N is called unistochastic if there exists a unitary U such that Bij=|Uij|2 for i,j=1,…,N. The set U3 of all unistochastic matrices of order N=3 forms a proper subset of the Birkhoff polytope, which contains all bistochastic (doubly stochastic) matrices. We compute the volume of the set U3 with respect to the flat (Lebesgue) measure and analytically evaluate the mean entropy of an unistochastic matrix of this order. We also analyze the Jarlskog invariant J, defined for any unitary matrix of order three, and derive its probability distribution for the ensemble of matrices distributed with respect to the Haar measure on U(3) and for the ensemble which generates the flat measure on the set of unistochastic matrices. For both measures the probability of finding |J| smaller than the value observed for the Cabbibo–Kobayashi–Maskawa matrix, which describes the violation of the CP parity, is shown to be small. Similar statistical reasoning may also be applied to the Maki–Nakagawa–Sakata matrix, which plays role in describing the neutrino oscillations. Some conjectures are made concerning analogous probability measures in the space of unitary matrices in higher dimensions.
Sound of carbon nanotube assemblies
Authors: Kozlov Mikhail E. , Haines Carter S. , Oh Jiyoung , Lima Marcio D. , Fang Shaoli
Published: December 2009

Strong thermo- and photoacoustic responses have been detected for aligned arrays of multiwalled carbon nanotube (MWNT) forests and solid drawn MWNT sheets. When heated using alternating current or a near-IR laser modulated in 100–20000Hz range, the nanotube assemblies generated loud, audible sound, with higher sound pressure being detected from the MWNT sheets. An evaluation of nonlinear distortions of the thermoacoustic signal revealed a highly peculiar behavior of the third and fourth harmonics produced from forests grown on silicon wafers. The peculiarities were especially pronounced for short forests and can be associated with the heat transfer from the MWNT layer to the substrate. For both types of nanotube assemblies, the acoustic signal’s amplitude varied with frequency approximately by the power low fp. The power factor p was found to be unexpectedly high for short forests probably due to heat loss to the substrate. The observed peculiarities can be used for the characterization of the prepared MWNT assemblies. The dependencies can also be helpful for evaluating the properties of thermal interfaces, in particular, those based on carbon nanotubes.
Internal friction and mode relaxation in a simple chain model
Authors: Fugmann S. , Sokolov I. M.
Published: December 2009

We consider the equilibrium relaxation properties of the end-to-end distance and of the principal components in a one-dimensional polymer chain model with nonlinear interaction between the beads. While for the single-well potentials these properties are similar to the ones of a Rouse chain, for the double-well interaction potentials, modeling internal friction, they differ vastly from the ones of the harmonic chain at intermediate times and intermediate temperatures. This minimal description within a one-dimensional model mimics the relaxation properties found in much more complex polymer systems. Thus, the relaxation time of the end-to-end distance may grow by orders of magnitude at intermediate temperatures. The principal components (whose directions are shown to coincide with the normal modes of the harmonic chain, whatever interaction potential is assumed) not only display larger relaxation times but also subdiffusive scaling.
Antibiotics in Respiratory Tract Infections — Communicating the NICE Guidance
Authors: Peet Danielle , Simon Chantal
Published: December 2009

Everybody regardless of age, ethnic background or socio-economic group has had at least one respiratory tract infection (RTI) in their lifetime and a quarter of the population will visit their GP with RTIs each year. Before antibiotics, secondary complications of usually self-limiting RTIs, such as pneumonia and quinsy, could be fatal. The discovery and development of penicillin by Fleming in the 1920's made antibiotics a lifesaver and they became increasingly prescribed for minor, usually self-limiting illness to prevent these complications. Over the years the cycle of medicalising self-limiting illness has continued. For example parents of children with otitis media are 30% more likely to attribute the improvement in the child to the antibiotics and not to their child's own immune system.
Regularization of linear and non-linear geophysical ill-posed problems with joint sparsity constraints
Authors: Gholami A. , Siahkoohi H. R.
Published: December 2009

In this paper, we deal with the solution of linear and non-linear geophysical ill-posed problems by requiring the solution to have sparse representations in two appropriate transformation domains, simultaneously. Geological structures are often smooth in properties away from sharp discontinuities (i.e. jumps in 1-D and edges in 2-D). Thus, an appropriate ‘regularizer’ function should be constructed so that recovers the smooth parts as well as the sharp discontinuities. Sparsity inversion techniques which require the solution to have a sparse representation with respect to a pre-selected basis or frames (e.g. wavelets), can recover the regions of smooth behaviour in model parameters well, but the solution suffers from the pseudo-Gibbs phenomenon, and is smoothed around discontinuities. On the other hand, requiring sparsity in Haar or finite-difference (FD) domain can lead to a solution without generating smoothed edges and the pseudo-Gibbs phenomenon. Here, we set up a regularizer function which can be benefited from the advantages of both wavelets and Haar/FD operators in representation of the solution. The idea allows capturing local structures with different smoothness in the model parameters and recovering smooth/constant pieces of the solution together with discontinuities. We also set up an information function without requiring the true model for selecting optimum wavelet and parameter β which controls the weight of the two sparsifying operators in the inverse algorithm.

For both linear and non-linear geophysical inverse problems, the performance of the method is illustrated with 1-D and 2-D synthetic examples and a field example from seismic traveltime tomography. In all of the examples tested, the proposed algorithm successfully estimated more credible and high-resolution models of the subsurface compared to those of the smooth and traditional sparse reconstructions.
Transcription profiling of eleven cytochrome P450s potentially involved in xenobiotic metabolism in the mosquito Aedes aegypti
Authors: Poupardin R. , Riaz M. A. , Vontas J. , David J. P. , Reynaud S.
Published: December 2009

Transcription profiles of 11 Aedes aegypti P450 genes from CYP6 and CYP9 subfamilies potentially involved in xenobiotic metabolism were investigated. Many genes were preferentially transcribed in tissues classically involved in xenobiotic metabolism including midgut and Malpighian tubules. Life‐stage transcription profiling revealed important variations amongst larvae, pupae, and adult males and females. Exposure of mosquito larvae to sub‐lethal doses of three xenobiotics induced the transcription of several genes with an induction peak after 48 to 72 h exposure. Several CYP genes were also induced by oxidative stress and one gene strongly responded to 20‐hydroxyecdysone. Overall, this study revealed that these P450s show different transcription profiles according to xenobiotic exposures, life stages or sex. Their putative chemoprotective functions are discussed.
Overlapping syndrome with familial partial lipodystrophy, Dunnigan variety and cardiomyopathy due to amino‐terminal heterozygous missense lamin A/C mutations
Authors: Subramanyam L , Simha V , Garg A
Published: December 2009

Subramanyam L, Simha V, Garg A. Overlapping syndrome with familial partial lipodystrophy, Dunnigan variety and cardiomyopathy due to amino‐terminal heterozygous missense lamin A/C mutations.

Familial partial lipodystrophy, Dunnigan variety (FPLD) is a well‐recognized autosomal dominant disorder due to heterozygous missense mutations in lamin A/C (LMNA) gene. Most of the FPLD patients harbor mutations in the C‐terminal of the lamin A/C and do not develop cardiomyopathy. On the other hand, affected subjects from three FPLD pedigrees with heterozygous R28W, R60G and R62G LMNA mutations in the amino‐terminal had associated cardiomyopathy presenting as premature onset of congestive heart failure, dilated cardiomyopathy and conduction system disturbances. We report three new FPLD pedigrees presenting with cardiomyopathy associated with heterozygous LMNA mutations in the amino‐terminal region. Two of them had previously reported R60G and R62G mutations and one has a novel D192V mutation. Affected subjects belonging to the pedigree with heterozygous R62G mutation had atrial fibrillation and required pacemaker implantation. The affected subjects from the other pedigrees with R60G and D192V mutations developed severe cardiomyopathy requiring defibrillator implantation and cardiac transplantation before 30 years of age in some and premature death in the fourth decade in others. Thus, our report provides further evidence of association of a multisystem dystrophy syndrome in FPLD patients harboring amino‐terminal mutations in LMNA. Increased understanding of the genotype–phenotype association might help devise clinical strategies aimed at preventing devastating manifestations of cardiomyopathy including heart failure, arrhythmias and sudden death. Furthermore, the underlying molecular mechanisms by which these amino‐terminal mutations cause lipodystrophy as well as cardiomyopathy remain to be understood.
Production and characterization of transgenic pigs expressing porcine CTLA4‐Ig
Authors: Phelps Carol J. , Ball Suyapa F. , Vaught Todd D. , Vance Amy M. , Mendicino Michael , Monahan Jeffrey A. , Walters Anneke H. , Wells Kevin D. , Dandro Amy S. , Ramsoondar Jagdeece J. , Cooper David K. C. , Ayares David L.
Published: December 2009

Phelps CJ, Ball SF, Vaught TD, Vance AM, Mendicino M, Monahan JA, Walters AH, Wells KD, Dandro AS, Ramsoondar JJ, Cooper DKC, Ayares DL. Production and characterization of transgenic pigs expressing porcine CTLA4‐Ig. Xenotransplantation 2009; 16: 477–485. © 2009 John Wiley & Sons A/S.

Abstract: Background:  Inhibition of the T‐cell‐mediated immune response is a necessary component of preventing rejection following xenotransplantation with pig α1,3‐galactosyltransferase gene‐knockout (GTKO) organs. Cytotoxic T lymphocyte‐associated antigen (CTLA4) is a co‐stimulatory molecule that inhibits T‐cell activity and may be useful in prolonging graft rejection.

Methods:  An expression vector was built containing the extracellular coding region of porcine (p) CTLA4 fused to the hinge and CH2/CH3 regions of human IgG1 (pCTLA4‐Ig). Pigs transgenic for pCTLA4‐Ig, on either a GTKO or wild‐type (WT) genetic background, were produced by nuclear transfer and characterized using Western blot analysis, immunofluorescence, ELISA, and necropsy.

Results:  Fifteen pCTLA4‐Ig‐transgenic piglets resulted from five pregnancies produced by nuclear transfer. All transgenic pigs exhibited robust expression of the pCTLA4‐Ig protein and most expressed the transgene in all organs analyzed, with significant levels in the blood as well. Despite initial good health, these pigs exhibited diminished humoral immunity, and were susceptible to infection, which could be managed for a limited time with antibiotics.

Conclusions:  Viable pigs exhibiting robust and ubiquitous expression of pCTLA4‐Ig were produced on both a WT and GTKO background. Expression of pCTLA4‐Ig resulted in acute susceptibility to opportunistic pathogens due at least in part to a significantly compromised humoral immune status. As this molecule is known to have immunosuppressive activity, high levels of pCTLA4‐Ig expression in the blood, as well as defective development related to exposure to pCTLA4‐Ig in utero, may contribute to this reduced immune status. Prophylactic treatment with antibiotics may promote survival of disease‐free transgenic pigs to a size optimal for organ procurement for transplantation. Additional genetic modifications and/or tightly regulated expression of pCTLA4Ig may reduce the impact of this transgene on the humoral immune system.
An infant with meningococcal arthritis of the hip
Authors: McMullan Brendan
Published: December 2009

Meningococcus is a well known cause of meningitis and septicaemia. It is less well known as a cause of arthritis. This case report describes an infant with meningococcal arthritis and with further discussion of the role of meningococcal serogroup W135 in disease, as well as current and future immunisation strategies.
Developing a methodology for assigning glycaemic index values to foods consumed across Europe
Authors: Aston L. M. , Jackson D. , Monsheimer S. , Whybrow S. , Handjieva‐Darlenska T. , Kreutzer M. , Kohl A. , Papadaki A. , Martinez J. A. , Kunova V. , Van Baak M. A. , Astrup A. , Saris W. H. M. , Jebb S. A. , Lindroos A. K.
Published: December 2009

There is growing evidence that the glycaemic index (GI) of the diet is important with respect to body weight and metabolic disease risk. However, research is limited by the paucity of GI values for commonly consumed carbohydrate‐rich foods in European countries. A new methodology has been developed for consistent assignment of GI values to foods across five European databases used in the Diogenes intervention study. GI values were assigned according to five decreasing levels of confidence (1)Measured valuesfor specific foods; (2)Published valuesfrom published sources; (3)Equivalent valueswhere published values for similar foods existed; (4)Estimated valuesassigned as one of three values representing low/medium/high GI ranges and (5)Nominal valuesassigned as 70, where no other value could be assigned with sufficient confidence. GI values were assigned to 5105 foods. In food records collected at baseline, the contribution to carbohydrate intake of foods assigned levels 1–2 ranged from 16% to 43% depending on country, and this increased to 53–81% including level 3 foods. The degree of confidence to assigned GI values differed across Europe. This standardized approach of assigning GI values will be made available to other researchers to facilitate further investigation into the effects of dietary GI on health.
Home Bias in Leveraged Buyouts*
Authors: Cornelius Peter , Juttmann Karlijn , Langelaar Broes
Published: December 2009

In this paper, we examine cross‐border investments in 2,260 portfolio companies by 102 buyout funds raised between 1995 and 2004. Using proprietary data compiled by AlpInvest Partners, we calculate the aggregate home bias of these funds as well as their home bias at the fund level. We find significant variation across funds. While UK‐based funds are on average least home‐biased, they show a high degree of intra‐European bias. In comparison, US funds are found to be least home‐biased in terms of inter‐regional acquisitions, with Europe being the most important destination for US buyout capital. Furthermore, we find that buyout funds tend to be less home‐biased than portfolio investors and, more specifically, mutual funds. This finding is consistent with the optimal ownership theory of the home bias, which predicts that foreign direct investment – as opposed to portfolio investment – represents the preferred choice of entry in countries where the quality of governance is perceived to be inferior, promoting insider ownership.
Soft Budget Constraints in EU Transition Economy Enterprises*
Authors: Moore Tomoe
Published: December 2009

Soft budget constraints (SBCs) can be said to exist in situations where governments rescue loss‐making firms in order to guarantee their survival by means of either a direct or an indirect injection of credit. The credit markets of the former socialist economies of Central and Eastern Europe were characterized, in general, by the syndrome of SBCs, whereby resources were often invested inefficiently. This paper empirically analyses the effect of joining the EU, where conditions for membership included the removal of SBCs, on restructuring the traditional financing methods for capital formation in EU transition economy enterprises. In the pre‐entry period, enterprises in the transition economies are found to be sensitive to credit in financing capital formation, exhibiting the prevalence of SBCs. However, the cost of capital becomes more important in the post‐entry period, which may be seen as a consequence of the reduced prevalence of SBCs, while market‐driven interest rates become more important in determining investment.