bluuebunny/crossref_metadata_2025 huggingface dataset:
Water
Authors: Freeman Ray
Published: November 2023

In spite of the amazing abundance of chemical information offered by NMR, it might still be argued that the most important sample is water, since the vast majority of medical applications focus on the proton signal from water in the human body. Water gives one of the strongest signals in the liquid phase, being 110 molar in protons. Historically, water seemed the natural choice to the Stanford group for their first NMR experiments (rather surprisingly, the Harvard group decided to go out and buy a sample of paraffin wax from the local hardware store). In the days when scientists built their own NMR spectrometers, water was the obvious choice for locating an NMR response for the first time. Even today, if something has gone seriously wrong with a high resolution spectrometer and the resonance condition has been lost, any fresh search for the correct field usually focuses on the proton signal from water, or on the deuterium signal from heavy water.
Measurement of coupling constants
Authors: Freeman Ray
Published: November 2023

Vicinal spin-spin coupling constants have proved to be of key importance for the determination of molecular conformation in solution. The foundation of all such studies is the Karplus equation1·2 which relates the three-bond coupling constant to the dihedral angle ø.
Social relationships within the community
Authors: Boesch Christophe , Boesch-Achermann Hedwige
Published: November 2023

Forest scene: One day in March 83, Malibu and Poupé e, two friends and both in oestrus, attracted all the males and led the whole crowd on their foraging trip. The desirable females regularly climbed in trees to rest, thus provoking high tension between the males. At 10.30, as they approached another tree, hostility arose again between alpha Brutus and Schubert. Macho immediately joined forces with Schubert. Both young males, their hair standing on end, faced Brutus and screamed at the top of their voices. Brutus had to choose between chasing them or remaining close to the females. Rousseau, another young male, bobbed and hoohed ten meters away without making it clear whom he was supporting. Falstaff, the senior male, approached Brutus in what looked like an attempt to quieten him. Brutus stretched his hand towards Falstaff, and Schubert had now to face both. Falstaff barked at him and Brutus chased Schubert and Macho up the big aerial roots of a Uapaca tree. Macho, farther away from Brutus, displayed above him. Schubert waited for Brutus to return to the females that had not moved and looked indifferent.
The origins of ecological diversity
Authors: Schluter Dolph
Published: November 2023

Adaptive radiation is the evolution of ecological diversity within a rapidly multiplying lineage. It is the differentiation of a single ancestor into an array of species that inhabit a variety of environments and that differ in traits used to exploit those environments. It includes the origin of new species and the evolution of ecological differences between them. It is regarded as the hallmark of adaptive evolution and may well be the most common syndrome in the origin and proliferation of taxa. The most dramatic living examples of adaptive radiation, such as the Galapagos finches (Fig. 1.1), the Hawaiian silverswords (Fig. 1.2), and the East African cichlid fishes (Fig. 1.3), rank with the dinosaur extinctions and the origin of our own species among the most celebrated events in the history of life.
The progress of adaptive radiation
Authors: Schluter Dolph
Published: November 2023

Does a recognizable progression exist in adaptive radiation or is each radiation unique? The idea of a characteristic sequence of events common to many radiations is appealing but has been little tested. One possibility proposed a number of times is that there should be a widespread trend toward greater niche specialization. Another is that the rate of morphological evolution should be highest early in a radiation and then decline steadily through time as species diversity builds. In this chapter I explore these and several other hypothesized trends using comparative and historical sources of data. This inquiry is necessarily descriptive, but its ultimate purpose is to establish whether there are regular features of ecological diversification that a complete theory of adaptive radiation eventually must explain.
Divergence and species interactions
Authors: Schluter Dolph
Published: November 2023

Interspecific competition for resources was regarded by the early naturalists as the second major cause of phenotypic differentiation in adaptive radiation. Under this view depletion of shared resources drives species to exploit new types, where they come under the influence of contrasting selection pressures. Lack (1947) was a strong proponent of this view. Interspecific competition was an important part of his overall interpretation of the extraordinary morphological variety of the Galapagos finches. His demonstration that the small and medium ground finches, which differ greatly in beak size where they occur together but converge in phenotype when present alone, remains among the most frequently cited examples of competition-induced divergence in phenotype. It pursuaded most naturalists of the time.
Collagen XII
Authors: Ricard-Blum Sylvie , Dublet * Bernard , der Rest Michel van
Published: November 2023

Collagen XII was discovered in a search at the nucleic acid level for an analogue of collagen IX in extracellular matrices containing collagen I [14, 49, 52]. Identified by screening a cDNA library constructed from tendon fibroblast mRNA [991], the corresponding pepsin-resistant fragments were isolated from embryonic chick tendons [921] and bovine periodontal ligament [953, 981]. Two collagen XII-like proteins, called TL-A and TL-B, were isolated from bovine skin and turned out to correspond to collagens XII, and XIV respectively [937, 1185]. The chick collagen XII molecule has also been designated as fibrochimerin [1045].
Systems with boundaries: compartments
Authors: Williams R J P , Silva J J R Fraústo Da
Published: November 2023

In the previous chapters of this book we have analysed the variables of unlimited chemical systems: percentage composition (in terms of components), temperature and pressure, but we have not considered the size or shape of any system we observe. In effect we have often drawn hypothetical boundaries around liquids and solids or considered gases in containers to separate them from a passive environment with which only energy (heat) could be exchanged (see Fig. 5.2), but we did not ask if any consequences stemmed from the existence of real boundaries or from the limitation of their volumes.
Change and its control
Authors: Williams R J P , Silva J J R Fraústo Da
Published: November 2023

In Chapters 1-6 we have described systems in equilibrium (stable) or in stationary states, where changes are not possible or so slow that they can be disregarded. We have also described systems in which there is fixed cyclic motion within stationary states. In Chapter 7 the discussion was extended to small amounts of materials in separated compartments at local equilibrium and included the effects of fields.
The evolution of man and his chemistry
Authors: Williams R J P , Silva J J R Fraústo Da
Published: November 2023

In this chapter we describe the latest great step in evolution, that to human beings (Table 15.1 and Fig. 15.1) which stresses the increase in differentiation based on the number of cell types. In fair part humans are animals, but they have two very distinctive features.
Heterogeneities in macroparasite infections: patterns and processes
Authors: Wilson K , ørnstad O N Bj , Dobson A P , Merler S , Poglayen G , Randolph S E , Read A F , Skorping A
Published: November 2023

Exhaustive empirical surveys have shown that, almost without exception, macroparasites (parasitic helminths and arthropods) are aggregated across their host populations, with most individuals harbouring low numbers of parasites, but a few individuals playing host to many (Shaw and Dobson 1995). Heterogeneities such as these are generated by variation between individuals in their exposure to parasite infective stages and by differences in their susceptibility once an infectious agent has been encountered. Experimental studies have shown that the extent of spatial aggregation in the infective stage distribution is reflected in the level of parasite aggregation across hosts (Keymer and Anderson 1979). Moreover, in the absence of any heterogeneity in exposure, even small differences in susceptibility between hosts can rapidly produce non-random, aggregated distributions of parasites (Anderson and May 1978). What is unclear at present, is the relative significance of these different mechanisms, and the importance of interactions between mechanisms in accentuating individual differences in parasite loads. Mathematical models that examine these problems rapidly become intractable (Grenfell et al. 1995), while experimental studies and computer simulations also become rather complex.
Evaluation of methods to design safer chemicals
Authors: Anastas Paul T , Warner John C
Published: November 2023

The methods to design safer chemicals are based on an analysis of how the molecular structure works in achieving its function, versus its ability to cause harm to human health and the environment. It is through the manipulation of the structure, such that the efficacy of function is maximized while the intrinsic hazard of a substance is minimized. that the design of a safer chemical is achieved. There is a common saying among designers of everything from automobiles to furniture to appliances; ‘form follows function’. This statement is as true at the molecular level as it is at the macro level.

The question therefore becomes. what is the function one wants to accomplish? This was a straightforward question prior to the time when society became aware of the unforeseen consequences of some chemical products. If one wanted to create a certain shade of red dye. then a molecular structure could be and was created to produce that red dye. rr one wanted to create an effective pesticide, then a molecular structure could be generated to serve that function, and so on. The problem as we know it now is not that the solution was incorrect, it was that the question was incorrect and/or incomplete.
Future trends in green chemistry
Authors: Anastas Paul T , Warner John C
Published: November 2023

The future of green chemistry is as broad as the future of chemistry as a whole and is therefore difficult to predict or summarize. Just as chemistry has always been a journey rather than a conclusion, green chemistry is also based on the premise that continual improvement, discovery, and innovation is the path towards the perfect goal of environmentally benign.

In this context there are, however, some areas of research that pose both a scientific challenge to chemists and have the potential for dramatic benefits as green chemistry alternatives to the current state of science.

While there have been notable advances in recent years, oxidation chemistry has had the mixed blessing of being both one of the most essential and one of the most polluting chemical technologies. It is certainly essential because oxidative transformations have been the basis of much of the necessary functionalization of fundamental chemical building blocks. Since the chemical industry currently relies almost exclusively on petroleum-based feedstocks, which are of course in their nearly fully reduced state, it is oxidation chemistry that allows these feedstocks to become the chemical products ultimately used by the consumer.
Regulation of gene transcription by hormones
Authors: Helmreich Ernst J M
Published: November 2023

Water-soluble hormones, growth factors, and cytokines must bind first to cell-surface receptors, but lipophilic, fat-soluble hormones can pass through the membrane lipid bilayer. Once inside the cell, they are recognized by diffusible receptor proteins which bring them to the nucleus where they control gene transcription. Thus, regulation of gene transcription by lipophilic hormones seems quite simple. There is, in principle, no need for transducers, linkers, and adaptors for transmission of a signal.
Regulation of the cell cycle
Authors: Helmreich Ernst J M
Published: November 2023

Cells have universal programmes to control growth, proliferation, and death. One of these programmes is the cell cycle which controls cell division. Progression through the cycle is controlled by external and internal signals. The cell cycle has a S phase, in which DNA is replicated, and an M phase, a mitotic phase, in which the replicated genetic information is divided into equal parts and passed on to the daughter cells. The interval between the S phase and the M phase in the cycle, in the right-handed direction of the clock, is the G2 phase, followed by the interval between the M phase and the next S phase, which is the G1 phase (Fig. 12.1; for more information, see ref. 1). However, in some cases, cited by Kim Nasmyth, biochemical and structural transitions of the cell-cycle machinery do not coincide with the cell-cycle phases to which they are assigned.
Loss of developmental controls in cancer
Authors: Helmreich Ernst J M
Published: November 2023

What we have considered up to this point, may have created the impression that only deregulation and dysfunctions of cellular proliferation cause cancer. Of course this is not true. Reactivation of developmental programmes operative in the embryo and the emergence of immature cell types play an important role in the genesis of tumours.
Psychobiological perspectives on early reactions to traumatic events
Authors: Shalev Arieh Y
Published: November 2023

The neurobiology of human responses to extreme events involves mechanisms related to bodily survival, learned conditioning, autobiographical memory-formation and complex, socially modulated, adaptation to change. The breadth of the topic is revealed by examining the time frames of some of the typical responses. These extend from fragments of seconds (for defence reflexes, such as auditory startle), several seconds (for sympathetic activation), tens of minutes (for activation of the hypothalamic-pituitary-adrenal axis), hours (for early gene expression), days (for memory consolidation) and months (for permanent changes in the central nervous system; Post, 1992).
Parkinson’s Disease and Related Disorders
Authors: Peterson Kendra
Published: November 2023

Palliative care for Parkinson’s disease (PD) is a poorly developed area of care. We do not understand the needs of Parkinson patients close to death and how best to meet these. Although many patients die of other diseases, almost certainly PD itself contributes to terminal decline in others. Despite this lack of knowledge it is possible to define where care can be improved. Knowledge of drug treatment is helpful, as is being aware of the multiplicity of problems of Parkinsonian patients in decline. A multidisciplinary approach is often the best way to address these needs and involvement of the palliative care team should be considered. There is an opportunity for further research to quantify and describe patients’ problems close to death to help deliver a better quality of care to endstage Parkinson patients.
Nausea and Vomiting
Authors: Mercadante Sebastiano
Published: November 2023

Nausea is an unpleasant sensation of the need to vomit and is associated with autonomic symptoms, including pallor, cold sweats, tachycardia, and diarrhea. It may occur without retching or vomiting and as a result of various stimuli. Although the neural pathways that mediate nausea are not known, evidence suggests that they are the same pathways that mediate vomiting. Different neurologic diseases may produce a disturbance in central control of gut motility, resulting in gastrointestinal syndromes such as vomiting or intestinal pseudo-obstruction with or without gastric stasis. There are no accepted treatment guidelines. The pharmacologic treatment of nausea and vomiting usually involves established drugs chosen and rotated as necessary on a trial basis. Many classes of medications have been employed as antiemetics.
Acute Confusional State
Authors: Bosisio Augusto Caraceni Marco
Published: November 2023

Confusion is one of the most prevalent symptoms in palliative care. Different etiologies such as primary CNS disorders, systemic diseases, and exogenous intoxication or drug withdrawal may converge in a final common pathway probably involving the cholinergic system of the brain stem. Clinically, the differential diagnosis includes dementia and conditions that can lead to delirium in advanced medical illness, and in the difficulties of managing this complex clinical syndrome for relatively prolonged periods of time at the end of life.
Respiratory Symptoms
Authors: KaIub-Wittemer Gian Domenico Borasio D
Published: November 2023

Dyspnea is a frequent symptom in neurologic disorders, especially neuromuscular disease. Careful assessment of the underlying cause is paramount. Like pain, ‘total dyspnea’ includes physical, psychosocial, and spiritual aspects. Drug and non-drug measures are equally important in the management of dyspnea. In neuromuscular patients, non-invasive ventilation is an excellent palliative measure for symptoms of chronic hypoventilation, while invasive ventilation should be restricted to selected cases. Other respiratory symptoms that can be efficiently palliated through appropriate medication include death rattle and cough. Management options for thick mucous secretions in patients with diaphragmatic weakness are still insufficient and further research is required.
Stomatitis
Authors: Rousseau PauI
Published: November 2023

Stomatitis is a painful and debilitating oral mucosal inflammation that reduces quality of life and precipitates and/or contributes to malnutrition, dehydration, an inability to communicate, and depression. The most significant risk factors for stomatitis are pre-existing oral or dental disease;l-3 medication use; infection; malnutrition; xerostomia; age older than 65 years or younger than 20 years; self-care deficits; exposure to additional oral stressors such as alcohol and tobacco;l,2 and sensitization to dyes. However, preventive measures are available to help preclude the development of stomatitis, including regular oral care and non-alcohol mouthwashes, but Upon examination, diffuse mucosal erythema was noted throughout the oral cavity without any observable discrete lesions. A preliminary diagnosis of a viral stomatitis versus aphthous stomatitis was made, and a generic non-alcoholic mouthwash was prescribed. After three days, the oral pain was significantly worse, and Mr D returned to his physician. Examination still revealed diffuse erythema. How-ever, his physician wondered about an atypical fungal stomatitis secondary to prior methylprednisolone use, and prescribed nystatin, 5 ml four times daily to swish and swallow. Within three days, Mr D was feeling better and able to eat and drink, the mucosal erythema was abating, and the diagnosis of fungal stomatitis was clinically confirmed.
Psychological Aspects
Authors: sloan Richard
Published: November 2023

The diagnosis of a neurological illness and its aftermath can have profound effects on all those involved-patients, their families, and also the health-care professionals looking after them. Patients’ reactions can vary from acceptance through naive ambivalence to abject horror. Dealing with the emotional reactions of patients has been highlighted as one of the most stressful areas for oncologists.l The same is likely to be true for progressive neurological
The Biological Chemistry of Magnesium: Phosphate Metabolism
Authors: Fraústo da Silva J J R , Williams R J P
Published: November 2023

Magnesium in biological chemistry is a Cinderella element: we know its hidden power and personality only indirectly since we are unable to label and follow it in a sensitive manner. Analysis in situ by X-ray fluorescence using the electron microscope is difficult since the element is light and present in the millimolar range; a very useful radioactive isotope is not available; there are few good spectroscopic tools (contrast calcium); even atomic absorption spectral methods need care because of the interference by phosphate with which magnesium is usually associated in cells.
Zinc: Lewis acid catalysis and regulation
Authors: Fraústo da Silva J J R , Williams R J P
Published: November 2023

At the beginning of each chapter on a given metal in living organisms we should have in mind the question as to why and how it has been selected for its particular tasks. In the present case the question itself has three parts: (1) why use zinc rather than another metal ion? (2) why use a metal ion at all since zinc is only an acid catalyst comparable to the proton? and (3) how has zinc been combined in order to use its properties optimally? As we stressed in Chapter 6, there are certain advantageous properties of metal ions both in their binding strengths and their rates of exchange of ligands which make them a potential source of chemically and hence biologically interesting selective properties. Zinc, Zn2+, is the case in point here. Its most obvious distinction is its highly concentrated charge since it is a small ion (radius 0.65 A).
Rearrangements of mitochondrial DNA
Authors: Schon Eric A
Published: November 2023

Both mitochondrial division and mtDNA replication are unrelated to the cell cycle or to the timing of nuclear DNA replication. Thus, a dividing cell has the potential to donate a variable number of organelles and genomes to its daughter cells, a phenomenon termed mitotic segregation. This process becomes important clinically if a patient is heteroplasmic, that is, he or she harbours two populations of mtDNA—normal mtDNAs and mutated mtDNAs causing a mitochondrial disease. Because of mitotic segregation, the phenotypic expression of a pathogenic mtDNA mutation may vary both in time (during development or over the course of a life-span) and in space (among tissues or cells).
Pathogenic mitochondrial DNA mutations in genes that encode respiratory chain subunits
Authors: Howell Neil
Published: November 2023

It has been 20 years since the publication of the sequence of the human mitochondrial genome1 and more than 10 years since the ‘dawn’ of studies on mitochondrial genetic diseases. With regard to the topic of this review, pathogenic mtDNA mutations in protein-encoding genes, ‘volume’ has greatly exceeded ‘space’. This is not a physical riddle, but the welcome reality of the current state of research. That is, the literature on such mtDNA mutations is now so large (and getting larger), that no single review of reasonable length can adequately summarize and critically evaluate the results.
Mouse models of mitochondrial disease
Authors: Graff Caroline , Larsson Nils-GÖran
Published: November 2023

Mitochondrial DNA has proved refractive to genetic engineering providing a major obstacle to creating animal models of mitochondrial DNA disease. Mitochondrial DNA (mtDNA) is located in the matrix enclosed by double membranes and there is as yet no method for introducing and stably maintaining foreign DNA in mitochondria. Most mouse models have therefore been generated by nuclear gene targeting (Table 15.1). However, it has recently been shown that it is possible to introduce isolated mitochondria into mouse embryos (Table 15.1).
Boundary-organized biomineralization
Authors: Mann Stephen
Published: November 2023

One key aspect of the biological control of mineralization is the partitioning of space either within or outside the cell by organic structures. We refer to this process as boundary-organized biomineralization. Because the enclosed environments are spatially defined and chemically separated from the general biochemical activity of the cellsthey have several important functions, including:
Multiple Sclerosis
Authors: Matthews Bryan , Rice-Oxley Margaret
Published: November 2023

For someone recently diagnosed with MS, or who lives with someone affected by MS, there are enormous new demands placed upon them, both physical and psychological. What has caused the illness? How will it affect their life? What can be done to alleviate the symptoms? Though much information on MS is available, there is a dearth of reliable advice that is based on proper medical research. For the sufferer, the conflicting and unreliable advice available can be a source of great confusion and frustration. As a new edition of a highly acclaimed book on this illness, Multiple Sclerosis: the facts explains in a clear and accessible manner, the symptoms, diagnosis, possible causes of multiple sclerosis, and lifecourse. In recent years there has been much controversy over new treatments such as Interferon, and the possible benefits of some alternative treatments. The new edition has been brought fully up to date and discusses the latest treatment options, including the latest results from trials of Interferon. A book that will be invaluable for those suffering from MS and those caring for them.
Masculine mothers in moderate collusion
Authors: Ulfstrand Staffan
Published: November 2023

The song of the hyena is one of the most magical of all the nightly sounds on the savannah. ‘Song’ is not an exaggeration, as hyenas can sing wonderful arias with clear, full alto voices and poignant expressiveness. Occasionally, these hyena songs are reminiscent of Mozart’s Queen of the Night.
At Home
Authors: Lee Elizabeth
Published: November 2023

David Williams lived his whole life in the Lake District. When he was sixty-five he developed a cancer of the bladder and was sent from his local hospital to a great specialist centre in Manchester where he received the finest treatment available. He was there for four weeks. His GP visited him when he came home and his first words to her were, ‘Oh doctor, thank God I’m home. You won’t send me away again will you?’ Of course she didn’t. Rather than die in the ward of a hospital in Manchester, he was able to live his last months at home surrounded by the lakes and mountains that he had always loved.
Common Symptoms and Their Treatment
Authors: Lee Elizabeth
Published: November 2023

This chapter will give a guide to the common symptoms experienced in terminal illness and outline the current mainstays of treatment. Most patients will suffer from one or more distressing symptoms and some are very common—anxiety, sleeplessness and depression, for example. Others, like bed sores and constipation, can often be prevented if certain precautions are taken. The symptoms relevant to most patients and carers are considered first, and then further common symptoms will be discussed. Use them for reference. My aim is both to give practical advice that will help you recognize and manage the conditions yourself, and to look at the medical treatment currently available.
Brain imaging studies in childhood-onset schizophrenia
Authors: Gogtay Nitin , Rapoport Judith L
Published: November 2023

Converging evidence indicates that serious childhood psychiatric disorders reflect subtle abnormalities of brain development. Clinical and neuropsychological studies indicate abnormal brain function in child psychiatric populations (Goodman 1994) and childhood psychiatric disorders are strongly associated with neurological and neurodevelopmental disorders (Rutter et al. 1970). With the advent of non-invasive brain MRI methodology, imaging data can now be safely acquired for pediatric populations. Interpretation of these data is substantiated by preclinical studies on the organization and function of neural circuits in the developing brain, and the molecular mediators of these changes.
Structural and functional brain abnormalities in first-episode schizophrenia
Authors: Sharma Tonmoy , Kumari Veena
Published: November 2023

Abundant evidence implicates abnormalities in almost all cortical and subcortical regions at least to some degree in schizophrenia. Understanding features of brain abnormalities in the first-episode (FE) psychosis is important for furthering our knowledge of the brain basis of schizophrenia. The FE is a crucial stage in the course of the disorder; it represents a transition from a premorbid to a morbid state and provides a valuable starting point for prospective and longitudinal studies.
Music and mathematics: an overview
Authors: Wollenberg Susan
Published: November 2023

The invitation to write an introduction to this collection offered a welcome opportunity to reflect on some of the historical, scientific, and artistic approaches that have been developed in the linking of mathematics and music. The two have traditionally been so closely connected that it is their separation that elicits surprise. During the late sixteenth and early seventeenth centuries when music began to be recognized more as an art and to be treated pedagogically as language and analysed in expressive terms, it might have been expected to lose thereby some of its scientific connotations; yet in fact the science of music went on to develop with renewed impetus.
Heterogeneous Domain Decomposition for Compressible Flows
Authors: Quarteroni A , Stolcis L
Published: November 2023

The motion of fluid flows is described by systems of non-linear partial differential equations, expressing the conservation principles of mass, momentum, and energy. From a physical point of view, the knowledge of the values of velocity and other physical quantities is sufficient for the description of fluid flows. The choice of the physical model to be employed has a great influence not only on the type of flow solution but also on the computational time needed to obtain it by numerical methods. Furthermore, each physical model has a certain range of validity and needs to be chosen according to the particular physical problem under investigation.
An Upwind Scheme for Magnetohydrodynamics
Authors: Powell K G , Roe P L , Myong R S , Gombosi T , Zeeuw D De
Published: November 2023

The governing equations of ideal magnetohydrodynamics (MHD) describe the physics of a conducting fluid in which the following assumptions hold: where ρ, V, τ and L are, respectively, characteristic density, speed, time and length scales for the problem, c is the speed of light, and ϵand σ represent the dielectric constant and conductivity of the fluid.
A Method to Obtain von Neumann Stability Conditions for the Convection-Diffusion Equation
Authors: Wesseling P
Published: November 2023

For the computation of time-dependent incompressible flows, the pressure-correction method is widely used. For the velocity prediction step something very close to the convection-diffusion equation is solved, and von Neumann stability analysis boils down to von Neumann stability analysis for the convection-diffusion equation, which is the topic of this paper. From now on, by stability we will mean stability in the sense of von Neumann, i.e. non-growth of Fourier components in the frozen coefficients case on an infinite domain.
Preconditioners for High Speed Flows 1n Aerospace Engineering
Authors: Hadcock K J , Xu X , Dubuc L , Richards B E
Published: November 2023

Progress is being made in numerically predicting complex three-dimensional viscous flows applicable to the external aerodynamics of aircraft flight at transonic, supersonic and hypersonic speeds influenced by the combined features of larger and faster computing resources at lower relative cost. Progress requires the development of improved algorithms which can effectively use the new computer architectures. The lower costs in high performance computing come mainly from the introduction of massively parallel processors (MPPs) with distributed memory architectures and code developments for industry need to respond to this trend. For viscous flows or flow unsteadiness, gains in efficiency are possible by using implicit time stepping [1] or Newton’s method [2]. Implicit methods generally have higher storage requirements which favours the distributed memory architecture approach.
A Krylov Preconditioner used Across the Time
Authors: Choquet R
Published: November 2023

In the past, some research has been done to solve compressible Navier Stokes equations by means of an implicit method. For two-dimensional structured meshes, Lerat[5] defined an implicit or centred method and obtained better performance than explicit methods for solving steady Euler problems. His scheme was unconditionally stable and allowed large time steps. Each time step led to an easy tridiagonal linear system to be solved. Also in the context of structured meshes a different approach was made in [4]. The authors considered the flow solver as a black box and applied an implicit scheme in time. In this context, the efficiency of the implicit method is less effective since non-symmetric linear problems have to be solved. An incomplete GMRES method was used to solve each linear system. Fast computation of the solution was obtained for the unsteady test case. But the author did not consider the error committed at each time step by the incomplete resolution of the linear system. Here, in the framework of unstructured meshes, we will consider the scheme as a black box and we will apply an implicit method when the problem is considered stiff, i.e. when an explicit method is “running badly”. In this context we describe a class of preconditioners for the GMRES method and we apply it to the linear systems arising from the implicit resolution of the compressible Navier-Stokes equations.
Modelling Natural Ventilation Using Computational Fluid Dynamics
Authors: Cook M , Lomas K , Howarth A , Crane M
Published: November 2023

Buildings must be provided with adequate ventilation. Environmental concerns, along with demands for energy efficiency are prompting designers to investigate natural ventilation as an alternative to mechanical ventilation or full air conditioning. One form of natural ventilation is displacement ventilation in which fresh air enters the room at low level, is drawn upwards in thermal plumes produced by equipment and occupants, and is then exhausted through high-level openings. This flow causes stratification where warm, stale air rises above fresh, ambient air. It is the layer of warm, buoyant air that drives the flow through the openings.
Tracking the Development of Vortex Flow Structures using Vortex Particle-in-Cell Methods
Authors: Doorly D J , Liu C H
Published: November 2023

A number of procedures for solving the Navier Stokes equations using the vorticity velocity formulation on an Eulerian grid have been developed, for example [1, 2].
An Adapted Newton Method for the Turbulent k—є Equations
Authors: Drexlerand1 M , Rollett2 J S
Published: November 2023

In this paper we present an adapted version of Newton’s Method in multidimensions and use it as a global solver for the turbulent k −ϵ equations. A symmetric duct serves as the test case for different Reynolds numbers. We give a geometrical interpretation of both the original and the adapted Newton’s Method in multiple dimensions. A convergence analysis is presented that shows linear conv rgence for Newton’s Method if the Jacobian is perturbed. Given this result, modelling the inlet corner points is discussed.
Simulation of Gas-particle Flow by Lattice Gas Methods
Authors: Filippova O , Hänel D
Published: November 2023

Particle-gas flow over rigid surfaces causes deposition of particles on the surface, resulting in a formation of porous or rigid layers. These layers change the form of the original bodies and therefore the flow field which influences the next particle deposition. Such surface effects determine essentially the efficiency of fibrous filters as used in many branches of industry. Analysis of the flow in real filters is nearly impossible due to the complex, mostly unknown geometry. But by reducing the problem to flow around a few periodically’ arranged obstacles some of the most essential effects and properties can be analyzed. The fluid flow is characterized by small speeds and small dimensions, resulting in small values of the Reynolds number.
Evaluation of the WAF Method for Kinematic and Dynamic Atmospheric Modelling Problems
Authors: Nikiforakis N , Toro E F
Published: November 2023

High-resolution, Riemann-problem-based (Godunov-type) methods have been used extensively and with great success in many scientific disciplines dealing with inert or reactive fluid flow problems. These offer conservative discretisations, exhibit no spurious oscillations near steep field gradients while maintaining at least second order accuracy in smoothly varying parts of the flow. Attractive such a package may be, yet this class of methods has not found its way into atmospheric flows.
Fluctuation Splitting Schemes for the Euler Equations on Quadrilateral Grids
Authors: van der weide E , Deconinck H
Published: November 2023

Over recent years, multi-dimensional upwind schemes for the Euler equations on 2D unstructured grids composed of triangles have come to maturity, as reviewed by Deconinck and Paillere [1] in this volume. However common experience indicates that quadrilaterals are to be preferred above triangles in stretched layers for which they are both more accurate and more economical. Ideally, triangles and quadrilaterals should be combined in hybrid grids, offering the best properties of both, geometric flexibility for triangles and optimal anisotropic stretching for quadrilaterals. The present paper makes a step in this direction by discussing the extension of the fluctuation splitting approach to grids composed of quadrilaterals.
Weather
Authors: Hoskins Brian
Published: November 2023

When we talk about the weather, we are referring to wind, rain, sunshine, frost and so on. The weatherman or woman on the television might stand in front of a chart like that in Fig. l(a) and forecast what the weather will be tomorrow. The weather map in Fig. l(a) shows lines of equal sea-level pressure drawn every Smb from 960mb to 1024mb (the unit mb will be defined later). Land H mark low-and high-pressure centres. Weather fronts are marked in bold with rounded bumps for the warm front and jagged bumps for the cold front. The little circles with symbols around them show the local weather. In particular the flags show the direction of the wind and the number of tail feathers indicates the strength. The dots show the rainfall with three dots being very heavy. The satellite image is a picture of the heat being given off rather than the light reflected. High cloud is cold and is shown as white. The ocean surface is warmer than the land surface at this time of year and so it shows as darker. The deep cloud swirls around the intense low pressure system. This storm gave intense winds and rainfall over the UK and has become known as the Burns Day storm.
Square Roots and Seventeengons
Authors: Kirwan Frances
Published: November 2023

This masterclass concerns a very old problem in mathematics which goes back to the ancient Greeks and was not solved until the nineteenth century; indeed, as we shall see, even today some questions remain unanswered. The solution involves some beautiful algebra which is often covered in second or third year university courses, but the problem itself is geometric and easy to explain. Since the earliest days of mathematics people have constructed geometric shapes using the most basic tools of geometry: a straight-edge for drawing straight lines and a pair of compasses for drawing circles (or, in their more primitive forms, any straight object and a drawing implement attached to a piece of string). The ancient Greeks (who were very sophisticated mathematicians) were particularly skilled at this; they were able to construct all sorts of different shapes using only these implements. They also invented much more complicated mechanisms to enable them to perform a wider range of constructions, but they preferred if possible to use a straight-edge and compasses alone.
Dynamics of Dinosaurs
Authors: Sewell Michael
Published: November 2023

We begin with some brief biological information, to make this account selfcontained and to serve as a background for the subsequent mathematics. Dinosaurs were a particular subclass of reptiles. Many were essentially land animals, and included the largest such which have ever lived. The following are examples. Diplodocus could be 27 metres long, which is 1½ times longer than a cricket pitch, and with a head about the size of a rhinocero’s head. It is shown in Fig. 1, fielding for the Reading University Academic Staff Cricket Club at mid-on (approximately), a position sometimes selected by the captain for Senior Lecturers whose fleetness of foot has become suspect. Its skeleton dominates the entrance hall of The Natural History Museum in London.
Water Waves
Authors: Wood Winifred
Published: November 2023

Imagine you are standing by a pond on a still day. There is not a breath of wind and the water surface is absolutely flat. You pick up a large stone and heave it into the water. You know what will happen -the stone makes a splash at the place where it enters the water and then small waves travel out from that place in concentric circles as in Fig. 1.
Malingering and illness deception
Authors: Halligan Peter W , Bass Christopher , Oakley David A
Published: November 2023

Despite a rich and turbulent history spanning several centuries, malingering continues to be a controversial and neglected clinical condition that has significant implications for medical, social, legal and insurance interests. Estimates of malingering - the wilful, intentional attempt to simulate or exaggerate illness in the pursuit of a consciously desired end - vary greatly, despite the fact that malingering is believed to contribute substantially to fraudulent health care and social welfare costs. There is little consensus about what would constitute a coherent assessment of malingering, and base rates have been difficult to establish. Malingering remains a difficult attribution to make not least since it falls outside the remit of the formal psychiatric classifications. Labelling a person as a malingerer however, has significant medico-legal, personal and economic ramifications for both subject and accuser. Viewed in this way, malingering is not so much illness behaviour in search of a disease, as the manifestation of a conflict between personal and social values. The aim of this book is to effect an integration of the different medical, forensic, neuropsychological, legal and social perspectives. The book provides an overview of progress in disparate fields relevant to the subject, including how recent social and neuroscience findings regarding volition, intentional states and theory of mind may have implications for informing detection, management and ultimately its explanation.
The nature of chronic pain: a clinical and legal challenge
Authors: Main Chris J
Published: November 2023

In cases of personal injury, in which litigation is involved, claimants need to prove they have been injured. In cases of chronic pain, this can be particularly problematic since pain is a subjective sen sation. Pain may be claimed in terms of self-report or may be inferred on the basis of observation of pain behaviour, but its legitimacy may be challenged. Given the difficulties of pursuing litigation it seems probable that total fabrication is rare, but the issue of exaggeration is frequently raised, particularly if there is considered to be a mismatch between the nature of the injury and the presenting symptoms or if the pain-associated disability is considered to be ‘excessive’. Unfortunately scientific studies have demonstrated a relatively weak relationship among these parameters, even in non-litigants and a degree of inconsistency in symptom presentation is not uncommon, particularly in distressed patients.
Animal models of stroke: implications for genetic studies of human stroke
Authors: Rubattu Speranza , Gigante Bruna , Stanzione Rosita , Volpe Massimo
Published: November 2023

Stroke represents a multifactorial and polygenic trait, resulting from a complex interaction between the genetic background and several environmental determinants (Rubattu et al. 2000).
Familial cerebral arteriovenous malformations
Authors: Labauge Pierre
Published: November 2023

Hereditary cerebral arteriovenous malformations mainly include hereditary haemorrhagic telangectasia (HHT) and familial cavernomas. Both of them belong to the group of capillary malformations. Familial cerebral arteriovenous or venous malformations have not been yet reported.
Investigating a patient with stroke for genetic causes
Authors: Markus Hugh S
Published: November 2023

Most cases of stroke have a multi-factorial pathogenesis. In such cases, although a genetic predisposition may be a risk factor in individual patients, identifying the underlying genetic basis is usually impossible, and is clinically not relevant. In contrast in a minority of stroke patients, abnormalities in a single gene are primarily responsible for the stroke.
Decision analysis of strategies to deal with non-compliance with TB treatment
Authors: Costa João G Q
Published: November 2023

Non-compliance in tuberculosis (TB) treatment is a major cause of concern because it increases the chance of drug resistance and of spreading the disease to others. Non-compliance requires resources that would not be used if the patient had followed the treatment. A patient who abandons the treatment and eventually comes back to start a new treatment has to be enrolled in a longer and more expensive drug scheme. In this way, the resources consumed in the first treatment are wasted and new resources have to be spent on the same patient. One of the reasons why the World Health Organization (WHO) supports DOT (directly observed treatment) is the increase in compliance achieved by this strategy, but DOT has been questioned as not feasible in many contexts.
The economic evaluation of HAI
Authors: Plowman Rosalind
Published: November 2023

Economic evaluation is concerned with the assessment of the costs and consequences of alternative practices, thus enabling the comparison of alternative interventions in order to obtain the maximum health gain for a given expenditure, or the lowest expenditure for a given health gain (Drummond et al. 1987).
Economics of animal health: implications for public health
Authors: Riviere-Cinnamond Ana
Published: November 2023

The past decade has witnessed an increase in emerging and re-emerging disease incidence. Bovine spongiform encephalopathy (BSE), severe acute respiratory syndrome (SARS), avian influenza (AI) and others have made the headlines of many newspapers. The population is therefore increasingly aware of the links and risks existing between animals and humans.
Trade and infectious disease outbreaks: ensuring public health without compromising free trade
Authors: Narasimhan Vasant
Published: November 2023

In today’s increasingly interconnected global economy, nations exchange goods and information with terrific speed while people travel with greater frequency and over longer distances. Nations depend now more than ever on international trade and tourism to be key components of their economies. In 2000, the World Trade Organization (WTO) estimated US$5.47 trillion in international merchandise trade and that 1.5 billion air travellers people travelled to other nations (World Trade Organization 2001). In addition to expanding trade and travel, however, the global economy has increased the potential speed and scale of infectious disease movement by destroying geographic containment. The potential now exists for a variety of infectious agents to spread via goods or people to new regions, with serious human health consequences.