bluuebunny/crossref_metadata_2025 huggingface dataset:
Challenging the Control of Knowledge in Colonial India: Political Ideas in the Work of S. R. Ranganathan
Authors: Roe George
Published: September 2010

Ranganathan's relevance for today is enhanced by a consideration of the political contexts and contradictions in his work. Identification with the Indian independence movement was central to his library theory. Ranganathan's pioneering work of the 1930s challenged the ideological structures of colonial rule, advocating libraries and librarians as agents of a national political awakening, especially amongst the rural poor. In doing so, Ranganathan laid claim to be the heir of the Enlightenment 'universal library' and even suggests the possible role of libraries in creating 'organic' intellectuals amongst the poor. However, the potential to spread mass self-education across India was lost through Ranganathan's simultaneous reliance on the state to deliver social reforms from above. This contradictory approach caused theoretical problems for him following Indian independence. Ranganathan saw the new state as the embodiment of the people, and yet the government did not deliver the scale of library development that Ranganathan needed to fulfil his work. Ranganathan became politically disorientated and marginalized within India. Lacking an organic link to a mass social movement, his ideas became increasingly abstract and obscure.
T. J. Wise and the City Librarian: Bibliographical Research — 1917 Style
Authors: Duckett Bob
Published: September 2010

During the course of 1917, there was an energetic correspondence between Thomas James Wise of London, who was preparing to publish a bibliography of the Brontë family, and Butler Wood, City Librarian of Bradford and Bibliographic Secretary of the Brontë Society. Wise, who compiled many bibliographies, came to rely on Wood's knowledge of sources and people for the publications, newspapers, and information he needed. The bibliography was prepared to a high standard and required that every source be checked. This correspondence gives a graphic insight into how bibliographic research was undertaken in the days before formal interlibrary lending and electronic databases. In particular, it demonstrates the value of personal knowledge and contacts, the shortcomings of the British Museum Library, and the international nature of such a venture.
The Architecture of the English Domestic Library, 1600–1700
Authors: Gwynn Lucy
Published: September 2010

The seventeenth century saw the dramatic growth of book collections, as books became a desirable commodity. The ruling classes used books to strengthen their political, social and intellectual hegemony, and the reading and collection of books was perceived as indicative of a range of virtues. At the same time, English society was increasingly receptive to new architectural ideas from the continent, and building and furnishing houses was a popular way of expressing morality and magnificence. This article identifies the relationship between patterns of reading, and the arrangement and architectural setting of book collections. Private libraries were a relative innovation, and the variety of approaches to accommodating them within the home often reflects the personal implications was conducted in the same terms used to debate the worth of reading and knowledge, and architectural display was a useful means of advertising an educated persona. The use of architectural style is also examined, since different motifs and stylistic approaches were attributed with different meanings, which related to shared ideas about knowledge, and its place within society.
Sixteenth-Century Private Book Inventories and Some Problems Related to their Analysis
Authors: Rial Benito
Published: September 2010

The first part of this paper sketches the interest that has been growing since the nineteenth century in private book inventories. It also examines the two primary ways in which book inventory studies have been undertaken: with the examination of a relevant single private book inventory or of a wide range of them. The second part of the paper examines some of the relevant obstacles to the correct identification and interpretation of sixteenth-century inventoried books. Such obstacles often result from categorizing and analysing private book inventories on the basis of received criteria and ignoring the differences between book inventory and book possession, book possession and book reading, and reading and text. This paper examines the problems in the formation and study of sixteenth-century private book inventories by focusing on Spanish examples. Such examples illustrate obstacles to the correct identification and interpretation of sixteenth-century inventoried books. The paper's general considerations are, nevertheless, equally applicable to other European sixteenth-century book inventories.
Cellular regulation of blood coagulation: a model for venous stasis
Authors: Campbell James E. , Brummel-Ziedins Kathleen E. , Butenas Saulius , Mann Kenneth G.
Published: September 2010

We have adapted the corn-trypsin inhibitor whole-blood model to include EA.hy926 as an endothelium surrogate to evaluate the vascular modulation of blood coagulation initiated by relipidated recombinant tissue factor (rTf) and a cellular Tf surrogate, lipopolysaccharide (LPS)-stimulated THP1 cells (LPS-THP-1). Compared with bare tubes, EA.hy926 with rTf decreased the rate of thrombin formation, ITS accumulation, and the production of fibrinopeptide A. These phenomena occurred with increased rates of factor Va (fVa) inactivation by cleavages at R506 and R306. Thus, EA.hy926 provides thrombin-dependent protein C activation and APC fVa inactivation. Comparisons of rTf with LPS-THP-1 showed that the latter gave reduced rates for TAT formation but equivalent fibrinopeptide A, and fV activation/inactivation. In the presence of EA.hy926, the reverse was obtained; with the surrogate endothelium and LPS-THP-1 the rates of TAT generation, fibrinopeptide release, and fV activation were almost doubled, whereas cleavage at R306 was equivalent. These observations suggest cooperativity between the 2 cell surrogates. These data suggest that the use of these 2 cell lines provides a reproducible quasi-endothelial quasi-inflammatory cytokine-stimulated monocyte system that provides a method to evaluate the variations in blood phenotype against the background of stable inflammatory cell activator and a stable vascular endothelial surrogate.
Near-saturated and complete genetic linkage map of black spruce (Picea mariana)
Authors: Kang Bum-Yong , Mann Ishminder K , Major John E , Rajora Om P
Published: September 2010

Background

Genetic maps provide an important genomic resource for understanding genome organization and evolution, comparative genomics, mapping genes and quantitative trait loci, and associating genomic segments with phenotypic traits. Spruce (Picea) genomics work is quite challenging, mainly because of extremely large size and highly repetitive nature of its genome, unsequenced and poorly understood genome, and the general lack of advanced-generation pedigrees. Our goal was to construct a high-density genetic linkage map of black spruce (Picea mariana, 2n = 24), which is a predominant, transcontinental species of the North American boreal and temperate forests, with high ecological and economic importance.

Results

We have developed a near-saturated and complete genetic linkage map of black spruce using a three-generation outbred pedigree and amplified fragment length polymorphism (AFLP), selectively amplified microsatellite polymorphic loci (SAMPL), expressed sequence tag polymorphism (ESTP), and microsatellite (mostly cDNA based) markers. Maternal, paternal, and consensus genetic linkage maps were constructed. The maternal, paternal, and consensus maps in our study consistently coalesced into 12 linkage groups, corresponding to the haploid chromosome number (1n = 1x = 12) of 12 in the genus Picea. The maternal map had 816 and the paternal map 743 markers distributed over 12 linkage groups each. The consensus map consisted of 1,111 markers distributed over 12 linkage groups, and covered almost the entire (> 97%) black spruce genome. The mapped markers included 809 AFLPs, 255 SAMPL, 42 microsatellites, and 5 ESTPs. Total estimated length of the genetic map was 1,770 cM, with an average of one marker every 1.6 cM. The maternal, paternal and consensus genetic maps aligned almost perfectly.

Conclusion

We have constructed the first high density to near-saturated genetic linkage map of black spruce, with greater than 97% genome coverage. Also, this is the first genetic map based on a three-generation outbred pedigree in the genus Picea. The genome length in P. mariana is likely to be about 1,800 cM. The genetic maps developed in our study can serve as a reference map for various genomics studies and applications in Picea a nd Pinaceae.
Neisseria meningitidis rifampicin resistant strains: analysis of protein differentially expressed
Authors: Neri Arianna , Mignogna Giuseppina , Fazio Cecilia , Giorgi Alessandra , Schininà Maria Eugenia , Stefanelli Paola
Published: September 2010

Background

Several mutations have been described as responsible for rifampicin resistance in Neisseria meningitidis. However, the intriguing question on why these strains are so rare remains open. The aim of this study was to investigate the protein content and to identify differential expression in specific proteins in two rifampicin resistant and one susceptible meningococci using two-dimensional electrophoresis (2-DE) combined with mass spectrometry.

Results

In our experimental conditions, able to resolve soluble proteins with an isoelectric point between 4 and 7, twenty-three proteins have been found differentially expressed in the two resistant strains compared to the susceptible. Some of them, involved in the main metabolic pathways, showed an increased expression, mainly in the catabolism of pyruvate and in the tricarboxylic acid cycle. A decreased expression of proteins belonging to gene regulation and to those involved in the folding of polypeptides has also been observed. 2-DE analysis showed the presence of four proteins displaying a shift in their isoelectric point in both resistant strains, confirmed by the presence of amino acid changes in the sequence analysis, absent in the susceptible.

Conclusions

The analysis of differentially expressed proteins suggests that an intricate series of events occurs in N. meningitidis rifampicin resistant strains and the results here reported may be considered a starting point in understanding their decreased invasion capacity. In fact, they support the hypothesis that the presence of more than one protein differentially expressed, having a role in the metabolism of the meningococcus, influences its ability to infect and to spread in the population. Different reports have described and discussed how a drug resistant pathogen shows a high biological cost for survival and that may also explain why, for some pathogens, the rate of resistant organisms is relatively low considering the widespread use of a particular drug. This seems the case of rifampicin resistant meningococci.
Identification of new polymorphic regions and differentiation of cultivated olives (Olea europaea L.) through plastome sequence comparison
Authors: Mariotti Roberto , Cultrera Nicolò GM , Díez Concepcion Muñoz , Baldoni Luciana , Rubini Andrea
Published: September 2010

Background

The cultivated olive (Olea europaea L.) is the most agriculturally important species of the Oleaceae family. Although many studies have been performed on plastid polymorphisms to evaluate taxonomy, phylogeny and phylogeography of Olea subspecies, only few polymorphic regions discriminating among the agronomically and economically important olive cultivars have been identified. The objective of this study was to sequence the entire plastome of olive and analyze many potential polymorphic regions to develop new inter-cultivar genetic markers.

Results

The complete plastid genome of the olive cultivar Frantoio was determined by direct sequence analysis using universal and novel PCR primers designed to amplify all overlapping regions. The chloroplast genome of the olive has an organisation and gene order that is conserved among numerous Angiosperm species and do not contain any of the inversions, gene duplications, insertions, inverted repeat expansions and gene/intron losses that have been found in the chloroplast genomes of the genera Jasminum and Menodora, from the same family as Olea.

The annotated sequence was used to evaluate the content of coding genes, the extent, and distribution of repeated and long dispersed sequences and the nucleotide composition pattern. These analyses provided essential information for structural, functional and comparative genomic studies in olive plastids. Furthermore, the alignment of the olive plastome sequence to those of other varieties and species identified 30 new organellar polymorphisms within the cultivated olive.

Conclusions

In addition to identifying mutations that may play a functional role in modifying the metabolism and adaptation of olive cultivars, the new chloroplast markers represent a valuable tool to assess the level of olive intercultivar plastome variation for use in population genetic analysis, phylogenesis, cultivar characterisation and DNA food tracking.
Social support and Quality of Life: a cross-sectional study on survivors eight months after the 2008 Wenchuan earthquake
Authors: Ke Xiong , Liu Chaojie , Li Ningxiu
Published: September 2010

Background

The 2008 Wenchuan earthquake resulted in extensive loss of life and physical and psychological injuries for survivors. This research examines the relationship between social support and health-related quality of life for the earthquake survivors.

Methods

A multistage cluster sampling strategy was employed to select participants from 11 shelters in nine counties exposed to different degrees of earthquake damage, for a questionnaire survey. The participants were asked to complete the Short Form 36 and the Social Support Rating Scale eight months after the earthquake struck. A total of 1617 participants returned the questionnaires. The quality of life of the survivors (in the four weeks preceding the survey) was compared with that of the general population in the region. Multivariate logistic regression analysis and canonical correlation analysis were performed to determine the association between social support and quality of life.

Results

The earthquake survivors reported poorer quality of life than the general population, with an average of 4.8% to 19.62% reduction in scores of the SF-36 (p < 0.001). The multivariate logistic regression analysis showed that those with stronger social support were more likely to have better quality of life. The canonical correlation analysis found that there was a discrepancy between actual social support received and perceived social support available, and the magnitude of this discrepancy was inversely related to perceived general health (rs = 0.467), and positively related to mental health (rs = 0.395).

Conclusion

Social support is associated with quality of life in the survivors of the earthquake. More attention needs to be paid to increasing social support for those with poorer mental health.
Hypoxic regulation of cytoglobin and neuroglobin expression in human normal and tumor tissues
Authors: Emara Marwan , Turner A Robert , Allalunis-Turner Joan
Published: September 2010

Background

Cytoglobin (Cygb) and neuroglobin (Ngb) are recently identified globin molecules that are expressed in vertebrate tissues. Upregulation of Cygb and Ngb under hypoxic and/or ischemic conditions in vitro and in vivo increases cell survival, suggesting possible protective roles through prevention of oxidative damage. We have previously shown that Ngb is expressed in human glioblastoma multiforme (GBM) cell lines, and that expression of its transcript and protein can be significantly increased after exposure to physiologically relevant levels of hypoxia. In this study, we extended this work to determine whether Cygb is also expressed in GBM cells, and whether its expression is enhanced under hypoxic conditions. We also compared Cygb and Ngb expression in human primary tumor specimens, including brain tumors, as well as in human normal tissues. Immunoreactivity of carbonic anhydrase IX (CA IX), a hypoxia-inducible metalloenzyme that catalyzes the hydration of CO2 to bicarbonate, was used as an endogenous marker of hypoxia.

Results

Cygb transcript and protein were expressed in human GBM cells, and this expression was significantly increased in most cells following 48 h incubation under hypoxia. We also showed that Cygb and Ngb are expressed in both normal tissues and human primary cancers, including GBM. Among normal tissues, Cygb and Ngb expression was restricted to distinct cell types and was especially prominent in ductal cells. Additionally, certain normal organs (e.g. stomach fundus, small bowel) showed distinct regional co-localization of Ngb, Cygb and CA IX. In most tumors, Ngb immunoreactivity was significantly greater than that of Cygb. In keeping with previous in vitro results, tumor regions that were positively stained for CA IX were also positive for Ngb and Cygb, suggesting that hypoxic upregulation of Ngb and Cygb also occurs in vivo.

Conclusions

Our finding of hypoxic up-regulation of Cygb/Ngb in GBM cell lines and human tumor tissues suggests that these globin molecules may be part of the repertoire of defense mechanisms that allow cancer cells to survive in hypoxic microenvironments.
Focusing on optic tectum circuitry through the lens of genetics
Authors: Nevin Linda M , Robles Estuardo , Baier Herwig , Scott Ethan K
Published: September 2010

The visual pathway is tasked with processing incoming signals from the retina and converting this information into adaptive behavior. Recent studies of the larval zebrafish tectum have begun to clarify how the 'micro-circuitry' of this highly organized midbrain structure filters visual input, which arrives in the superficial layers and directs motor output through efferent projections from its deep layers. The new emphasis has been on the specific function of neuronal cell types, which can now be reproducibly labeled, imaged and manipulated using genetic and optical techniques. Here, we discuss recent advances and emerging experimental approaches for studying tectal circuits as models for visual processing and sensorimotor transformation by the vertebrate brain.
An arthropod cis-regulatory element functioning in sensory organ precursor development dates back to the Cambrian
Authors: Ayyar Savita , Negre Barbara , Simpson Pat , Stollewerk Angelika
Published: September 2010

Background

An increasing number of publications demonstrate conservation of function of cis-regulatory elements without sequence similarity. In invertebrates such functional conservation has only been shown for closely related species. Here we demonstrate the existence of an ancient arthropod regulatory element that functions during the selection of neural precursors. The activity of genes of theachaete-scute(ac-sc) family endows cells with neural potential. An essential, conserved characteristic of proneural genes is their ability to restrict their own activity to single or a small number of progenitor cells from their initially broad domains of expression. This is achieved through a process called lateral inhibition. A regulatory element, the sensory organ precursor enhancer (SOPE), is required for this process. First identified inDrosophila, the SOPE contains discrete binding sites for four regulatory factors. The SOPE of theDrosophila asensegene is situated in the 5' UTR.

Results

Through a manual comparison of consensus binding site sequences we have been able to identify a SOPE in UTR sequences ofasense-like genes in species belonging to all four arthropod groups (Crustacea, Myriapoda, Chelicerata and Insecta). The SOPEs of the spiderCupiennius saleiand the insectTribolium castaneumare shown to be functional in transgenicDrosophila. This would place the origin of this regulatory sequence as far back as the last common ancestor of the Arthropoda, that is, in the Cambrian, 550 million years ago.

Conclusions

The SOPE is not detectable by inter-specific sequence comparison, raising the possibility that other ancient regulatory modules in invertebrates might have escaped detection.
Presenilin-1 regulates induction of hypoxia inducible factor-1α: altered activation by a mutation associated with familial Alzheimer's disease
Authors: De Gasperi Rita , Sosa Miguel A Gama , Dracheva Stella , Elder Gregory A
Published: September 2010

Background

Mutations in presenilin-1 (Psen1) cause familial Alzheimer's disease (FAD). Both hypoxia and ischemia have been implicated in the pathological cascade that leads to amyloid deposition in AD. Here we investigated whether Psen1 might regulate hypoxic responses by modulating induction of the transcription factor hypoxia inducible factor 1-α (HIF-1α).

Results

In fibroblasts that lack Psen1 induction of HIF-1α was impaired in response to the hypoxia mimetic cobalt chloride, as well as was induction by insulin and calcium chelation. Reintroduction of human Psen1 using a lentiviral vector partially rescued the responsiveness of Psen1-/- fibroblasts to cobalt chloride induction. HIF-1α induction did not require Psen1's associated γ-secretase activity. In addition, the failure of insulin to induce HIF-1α was not explicable on the basis of failed activation of the phosphatidylinositol 3-kinase (PI3K/Akt) pathway which activated normally in Psen1-/- fibroblasts. Rather we found that basal levels of HIF-1α were lower in Psen1-/- fibroblasts and that the basis for lower constitutive levels of HIF-1α was best explained by accelerated HIF-1α degradation. We further found that Psen1 and HIF-1α physically interact suggesting that Psen1 may protect HIF-1α from degradation through the proteasome. In fibroblasts harboring the M146V Psen1 FAD mutation on a mouse Psen1 null background, metabolic induction of HIF-1α by insulin was impaired but not hypoxic induction by cobalt chloride. Unlike Psen1-/- fibroblasts, basal levels of HIF-1α were normal in FAD mutant fibroblasts but activation of the insulin-receptor pathway was impaired. Interestingly, in Psen1-/- primary neuronal cultures HIF-1α was induced normally in response to cobalt chloride but insulin induction of HIF-1α was impaired even though activation of the PI3K/Akt pathway by insulin proceeded normally in Psen1-/- neuronal cultures. Basal levels of HIF-1α were not significantly different in Psen1-/- neurons and HIF-1α levels were normal in Psen1-/- embryos.

Conclusions

Collectively these studies show that Psen1 regulates induction of HIF-1α although they indicate that cell type specific differences exist in the effect of Psen1 on induction. They also show that the M146V Psen1 FAD mutation impairs metabolic induction of HIF-1α, an observation that may have pathophysiological significance for AD.
Dynamic instability of genomic methylation patterns in pluripotent stem cells
Authors: Ooi Steen KT , Wolf Daniel , Hartung Odelya , Agarwal Suneet , Daley George Q , Goff Stephen P , Bestor Timothy H
Published: September 2010

Background

Genomic methylation patterns are established during gametogenesis, and perpetuated in somatic cells by faithful maintenance methylation. There have been previous indications that genomic methylation patterns may be less stable in embryonic stem (ES) cells than in differentiated somatic cells, but it is not known whether different mechanisms of de novo and maintenance methylation operate in pluripotent stem cells compared with differentiating somatic cells.

Results

In this paper, we show that ablation of the DNA methyltransferase regulator DNMT3L (DNA methyltransferase 3-like) in mouse ES cells renders them essentially incapable of de novo methylation of newly integrated retroviral DNA. We also show that ES cells lacking DNMT3L lose DNA methylation over time in culture, suggesting that DNA methylation in ES cells is the result of dynamic loss and gain of DNA methylation. We found that wild-type female ES cells lose DNA methylation at a much faster rate than do male ES cells; this defect could not be attributed to sex-specific differences in expression of DNMT3L or of any DNA methyltransferase. We also found that human ES and induced pluripotent stem cell lines showed marked but variable loss of methylation that could not be attributed to sex chromosome constitution or time in culture.

Conclusions

These data indicate that DNA methylation in pluripotent stem cells is much more dynamic and error-prone than is maintenance methylation in differentiated cells. DNA methylation requires DNMT3L in stem cells, but DNMT3L is not expressed in differentiating somatic cells. Error-prone maintenance methylation will introduce unpredictable phenotypic variation into clonal populations of pluripotent stem cells, and this variation is likely to be much more pronounced in cultured female cells. This epigenetic variability has obvious negative implications for the clinical applications of stem cells.
Nonidentifiability of the Two-State Markovian Arrival Process
Authors: Ramírez-Cobo Pepa , Lillo Rosa E. , Wiper Michael P.
Published: September 2010

In this paper we consider the problem of identifiability for the two-state Markovian arrival process (MAP2). In particular, we show that the MAP2is not identifiable, providing the conditions under which two different sets of parameters induce identical stationary laws for the observable process.
Recovering a Piecewise Constant Volatility from Perpetual Put Option Prices
Authors: Lu Bing
Published: September 2010

In this paper we present a method to recover a time-homogeneous piecewise constant volatility from a finite set of perpetual put option prices. The whole calculation process of the volatility is decomposed into easy computations in many fixed disjoint intervals. In each interval, the volatility is obtained by solving a system of nonlinear equations.
The Continuous-Time Ehrenfest Process in Term Structure Modelling
Authors: Kaplun A.
Published: September 2010

In this paper, a finite-state mean-reverting model for the short rate, based on the continuous-time Ehrenfest process, will be examined. Two explicit pricing formulae for zero-coupon bonds will be derived in the general and special symmetric cases. Its limiting relationship to the Vasicek model will be examined with some numerical results.
An Almost-Sure Renewal Theorem for Branching Random Walks on the Line
Authors: Meiners Matthias
Published: September 2010

In the present paper an almost-sure renewal theorem for branching random walks (BRWs) on the real line is formulated and established. The theorem constitutes a generalization of Nerman's theorem on the almost-sure convergence of Malthus normed supercritical Crump-Mode-Jagers branching processes counted with general characteristic and Gatouras' almost-sure renewal theorem for BRWs on a lattice.
Poisson Approximation of the Number of Cliques in Random Intersection Graphs
Authors: Rybarczyk Katarzyna , Stark Dudley
Published: September 2010

A random intersection graphG(n,m,p) is defined on a setVofnvertices. There is an auxiliary setWconsisting ofmobjects, and each vertexv∈Vis assigned a random subset of objectsWv⊆Wsuch thatw∈Wvwith probabilityp, independently for allv∈Vand allw∈W. Given two verticesv1,v2∈V, we setv1∼v2if and only ifWv1∩Wv2≠ ∅. We use Stein's method to obtain an upper bound on the total variation distance between the distribution of the number ofh-cliques inG(n,m,p) and a related Poisson distribution for any fixed integerh.
Phases in the Diffusion of Gases via the Ehrenfest URN Modelx
Authors: Balaji Srinivasan , Mahmoud Hosam , Tong Zhang
Published: September 2010

The Ehrenfest urn is a model for the diffusion of gases between two chambers. Classic research deals with this system as a Markovian model with a fixed number of balls, and derives the steady-state behavior as a binomial distribution (which can be approximated by a normal distribution). We study the gradual change for an urn containingn(a very large number) balls from the initial condition to the steady state. We look at the status of the urn afterkndraws. We identify three phases ofkn: the growing sublinear, the linear, and the superlinear. In the growing sublinear phase the amount of gas in each chamber is normally distributed, with parameters that are influenced by the initial conditions. In the linear phase a different normal distribution applies, in which the influence of the initial conditions is attenuated. The steady state is not a good approximation until a certain superlinear amount of time has elapsed. At the superlinear stage the mix is nearly perfect, with a nearly perfect symmetrical normal distribution in which the effect of the initial conditions is completely washed away. We give interpretations for how the results in different phases conjoin at the ‘seam lines’. In fact, these Gaussian phases are all manifestations of one master theorem. The results are obtained via martingale theory.
Mixture Representations of Inactivity Times of Conditional Coherent Systems and their Applications
Authors: Zhang Zhengcheng
Published: September 2010

In this paper we obtain several mixture representations of the reliability function of the inactivity time of a coherent system under the condition that the system has failed at timet(> 0) in terms of the reliability functions of inactivity times of order statistics. Some ordering properties of theinactivity timesof coherent systems with independent and identically distributed components are obtained, based on the stochastically ordered coefficient vectors between systems.
Limit of the Transport Capacity of a Dense Wireless Network
Authors: Ganti Radha Krishna , Haenggi Martin
Published: September 2010

It is known that the transport capacity of a dense wireless ad hoc network with n nodes scales like √n. We show that the transport capacity divided by √n approaches a nonrandom limit with probability 1 when the nodes are uniformly distributed on the unit square. To show the existence of the limit, we prove that the transport capacity under the protocol model is a subadditive Euclidean functional and use the machinery of subadditive functions in the spirit of Steele.
Analysis of a bimetallic slab in non-isothermal flow
Authors: Turan E , Ecder A
Published: September 2010

The main object of this study is to investigate a fluid—structure interaction problem using Newton—Krylov techniques. As a test problem, a bimetallic slab exposed to a non-isothermal flow field is selected. If the metals on the body have different coefficients of thermal expansion, then the structure deflects in the case of a temperature change. In this study, natural convection is the reason for the temperature gradient on the slab. Solution of incompressible Navier—Stokes equations are weakly coupled with the linearized quasi-static thermoelasticity problem. The Stream function—vorticity approach is used to analyse the governing equations of the flow problem and finite differences are used for discretization. The finite-element method is preferred to solve the deflection of the solid which is modelled with plane strain assumption. Matrix-free methodology is utilized in the Newton—Krylov solver. The inexact Newton method is employed along with preconditioned Generalized Minimum RESidual as the linear solver. Domain decomposition is utilized both to ease the solution of the deformed flow geometry and to separate both physics. Several computations are performed for various Rayleigh numbers and various results are presented.
A new effective method to predict the permanent deformation of plane plates subjected to underwater shock loading
Authors: Li L-J , Jiang W-K
Published: September 2010

Theoretical analysis of the shock loading acting on a plane plate is performed for an underwater explosion. An effective new numerical method is used to simulate the plate plastic permanent deformation based on the shock loading acting on the plate. During the numerical simulation, only the structure domain is modelled and gas bubble reloading is ignored, and so computation efficiency is highly improved. The numerical results are modified based on the distribution of shock energy during the underwater explosion, and the modified numerical results are in good agreement with the experimental results.
Free vibration analysis of functionally graded thin annular sector plates using the differential quadrature method
Authors: Mirtalaie S H , Hajabasi M A
Published: September 2010

In this article, the differential quadrature method (DQM) is used to study the free vibration of functionally graded (FG) thin annular sector plates. The material properties of the FG-plate are assumed to vary continuously through the thickness, according to the power-law distribution. The governing differential equations of motion are derived based on the classical plate theory and solved numerically using DQM. The natural frequencies of thin FG annular sector plates under various combinations of clamped, free, and simply supported boundary conditions are presented for the first time. To ensure the accuracy of the method, the natural frequencies of a pure metallic plate are calculated and compared with those existing in the literature for the homogeneous plate. In this case, the result shows very good agreement. For the FG-plates, the effects of boundary conditions, volume fraction exponent, and variation of Poisson's ratio on the free vibrational behaviour of the plate are studied.
Modal synthesis of belt-rib structures
Authors: Hasse A , Zuest I , Campanile L F
Published: September 2010

In contrast to conventional mechanisms, compliant mechanisms exploit structural flexibility to produce controllable large deformations. Belt-rib airfoils are shape-adaptable lightweight structures based on this idea. A belt-rib structure originally consists of a deformable closed shell (belt) whose kinematic degrees of freedom are constrained by inner stiffeners called spokes. Using standard spoke elements, the possible profile changes of the airfoil are limited.

The purpose of the work reported in the current article is to define an inner stiffening structure based on numerical topology optimization in order to realize arbitrary profile changes. A ground structure with moveable connection points within the external belt represents the set of possible topologies and shapes. A new modal objective function for the synthesis of compliant mechanisms with selective compliance is introduced. The optimization problem is approached by using genetic algorithms.

The applicability of the current procedure is validated by a profile shape adaptation example. For this purpose, an initial profile shape and a target profile shape are defined. The outcome of the procedure is a complex inner stiffening structure, which fulfils the imposed requirements. The solution is validated by modal analysis based on an finite-element model. Furthermore, the structural behaviour is experimentally investigated.
Optimizing piezoelectric panel speakers using the simulated annealing algorithm
Authors: Bai M R , Tsai Y K
Published: September 2010

This article focuses on the optimization of piezoelectric panel speakers. Two piezoelectric ceramic plates serve to excite the diaphragm in the speaker. In light of an optimization procedure, the optimal position on the diaphragm to mount the piezoelectric ceramic plates is determined. A finite-element model is established using the energy method, where the electrical system, mechanical system, and acoustic loading of the transducer are considered as a coupled system. The simulated annealing algorithm is exploited to attain a design that enables low fundamental resonance frequency and high acoustic output. Experiments were conducted to verify the numerical model. The experimental results were in good agreement with the numerical prediction, in which the performance of the optimized configuration was found to be significantly improved over the non-optimal design.
Analysis of the Nominal Load Effects on Gear Load Capacity Using the Finite-Element Method
Authors: Atanasovska I , Mitrović R , Momĉilović D , Subic A
Published: September 2010

This research investigates the effects of the nominal load value on load distribution of simultaneously meshing gear teeth pairs, and on the involute gear load capacity. The research results presented in this article confirm that the nominal load value has a significant influence on the gear load capacity calculations. However, this influence is generally neglected in standard gear calculations, which can result in oversized gear dimensions. This can lead to inadequate gear designs in practice due to increased demand for reduced gear size and weight in modern machinery. The article provides a detailed description of the iterative numerical method developed in this research to support the modelling and analysis of load distribution in meshed gears using the finite-element method.
Epidemiology and aetiology of C4–6 disease
Authors: Bradbury Andrew W
Published: September 2010

Although our understanding of chronic venous insufficiency (CVI) has improved, many important questions remain unanswered. Ensuring that patients are appropriately referred for specialist assessment and then receive evidence-based, cost-effective treatment continues to be challenging. The lifetime of risk of chronic venous ulceration (CVU) is around 1% with approximately 10% ulcers being open at any one time. The incidence skin changes disease is about 10 times greater (10%). However, many of the studies upon which these estimates are based are old and/or methodologically flawed. There is reason to believe that the incidence, prevalence and characteristics of CVI/CVU may have changed considerably over the last 10–20 years and that future change is likely. Further cross-sectional and longitudinal epidemiological studies are required to establish the size and nature of the health-care need going forward in developed and increasingly developing countries. CVI culminating CVU is primarily the result of sustained ambulatory venous hypertension, which in turn arises from superficial and/or deep venous reflux with or without deep vein obstruction. However, there are many other elements to this complex condition, for example, microvascular dysfunction; calf muscle pump efficiency; dermal inflammation; disordered fibroblast function and matrix production; failure of epithelialization; congenital and acquired thrombophilia; malnutrition, obesity and diet; and bacterial colonization. None of the currently available treatment modalities is entirely satisfactory and novel therapies based upon a clearer understanding of the disease at the psychological, genetic, mechanical, microvascular and microscopic level are required.
Investigation of the patient with a venous ulcer
Authors: Mcaree B J , Berridge D C
Published: September 2010

This review concentrates on the investigation of the patient with venous ulceration with a view to presenting current best practice. The aim is to maximize benefit for patients and their medical team by directing appropriate investigation leading to optimized results in the treatment of this highly prevalent, quality of life reducing and socioeconomically costly condition.
Pharmacological treatment in patients with C4, C5 and C6 venous disease
Authors: Gohel M S , Davies A H
Published: September 2010

Background

A range of surgical, endovenous, physical and medical treatments are available for patients with chronic venous disease. The aim of this review was to evaluate the evidence for pharmacological agents used for the treatment of chronic venous disease.

Methods

A literature search was performed using Pubmed, Embase, Cochrane and Google Scholar databases. The initial search terms ‘varicose vein’, ‘venous ulcer’, ‘venous disease’ and ‘lipodermatosclerosis’ were used to identify relevant clinical studies of pharmacotherapy in patients with chronic venous disease (C4–C6).

Results

A huge range of naturally occurring and synthetic drugs have been studied in patients with chronic venous disease. For patients with C4 venous disease, micronized purified flavonoid fraction (MPFF), oxerutin, rutosides and calcium dobesilate may reduce venous symptoms and oedema. MPFF and pentoxifylline have been shown to improve venous ulcer healing when used in addition to multilayer compression bandaging. The clinical benefits of other medications remain unproven. Reliability of meta-analyses was limited by study heterogeneity, small sample sizes and lack of long-term follow-up.

Conclusions

In prospective randomized studies, MPFF (Daflon®), other flavonoid derivatives and pentoxifylline have demonstrated clinical benefits in patients with C4–C6 venous disease. Pharmacotherapy should be part of a range of treatment options in the modern management of patients with chronic venous disorders.
From lymph to fat: complete reduction of lymphoedema
Authors: Brorson H
Published: September 2010

Liposuction for late-stage lymphoedema remains a controversial technique. While it is clear that conservative therapies such as combined decongestive therapy (CDT) and controlled compression therapy (CCT) should be tried in the first instance, options for the treatment of late-stage lymphoedema that is not responding to treatment is not so clear. Liposuction has been used for many years to treat lipodystrophy. Some results have been far from optimal; however, improvements in technique, patient preparation and patient follow-up have led to a greater and a wider acceptance of liposuction as a treatment for lymphoedema. This paper outlines the benefits of using liposuction and presents the evidence to support its use.
The need for a National Service Framework for leg ulcers
Authors: Bulbulia R A , Poskitt K R
Published: September 2010

Leg ulcers are common and costly to treat, and the quality of care provided to patients with this condition varies widely across the UK. The introduction of specialized community-based leg ulcer clinics in Gloucestershire has been associated with increased ulcer healing rates and decreased rates of ulcer recurrence, but this model of care has not been widely replicated. One way of ending this ‘postcode lottery’ is to produce a National Service Framework for leg ulcers, with the aim of delivering high-quality evidence-based care via such clinics under the supervision of local consultant vascular surgeons. Existing National Service Frameworks cover a range of common conditions that are, like leg ulceration, associated with significant morbidity, disability and resource use. These documents aim to raise quality and decrease regional variations in health care across the National Health Service, and leg ulceration fulfils all the necessary criteria for inclusion in a National Service Framework. Centrally defined standards of care for patients with leg ulceration, and the reorganization and restructuring of local services to allow the accurate assessment and treatment of such patients are required. Without a National Service Framework to drive up the quality of care across the country, the treatment of patients with leg ulcers will remain suboptimal for the majority of those who suffer from this common and debilitating condition.
Cranial hydatid abscess
Authors: Zahed Hossain Md , Mizanur Rahman Md , Mohammad Badruddoza Shah
Published: September 2010

A woman of age 20 years presented with a tender cystic swelling over the right temporal region, with proptosis of the right eye and purulent discharge from the right ear. A computed tomography scan revealed a mixed density lesion involving both extra- and intracranial spaces, which was not enhanced with contrast. Following an operation, histopathology revealed the structure to be a hydatid abscess (infected hydatid cyst).
Acute undifferentiated febrile illness in adult hospitalized patients: the disease spectrum and diagnostic predictors – an experience from a tertiary care hospital in South India
Authors: Chrispal Anugrah , Boorugu Harikishan , Gopinath Kango Gopal , Chandy Sara , Prakash John Antony Jude , Thomas Elsa Mary , Abraham Asha Mary , Abraham O C , Thomas Kurien
Published: September 2010

Local prevalences of individual diseases influence the prioritization of the differential diagnoses of a clinical syndrome of acute undifferentiated febrile illness (AFI). This study was conducted in order to delineate the aetiology of AFI that present to a tertiary hospital in southern India and to describe disease-specific clinical profiles. An 1-year prospective, observational study was conducted in adults (age >16 years) who presented with an undifferentiated febrile illness of duration 5–21 days, requiring hospitalization. Blood cultures, malarial parasites and febrile serology (acute and convalescent), in addition to clinical evaluations and basic investigations were performed. Comparisons were made between each disease and the other AFIs. A total of 398 AFI patients were diagnosed with: scrub typhus (47.5%); malaria (17.1%); enteric fever (8.0%); dengue (7.0%); leptospirosis (3.0%); spotted fever rickettsiosis (1.8%); Hantavirus (0.3%); alternate diagnosis (7.3%); and unclear diagnoses (8.0%). Leucocytosis, acute respiratory distress syndrome, aseptic meningitis, mild serum transaminase elevation and hypoalbuminaemia were independently associated with scrub typhus. Normal leukocyte counts, moderate to severe thrombocytopenia, renal failure, splenomegaly and hyperbilirubinaemia with mildly elevated serum transaminases were associated with malaria. Rash, overt bleeding manifestations, normal to low leukocyte counts, moderate to severe thrombocytopenia and significantly elevated hepatic transaminases were associated with dengue. Enteric fever was associated with loose stools, normal to low leukocyte counts and normal platelet counts. It is imperative to maintain a sound epidemiological database of AFIs so that evidence-based diagnostic criteria and treatment guidelines can be developed.
Structural basis for recognition ofS-adenosylhomocysteine by riboswitches
Authors: Edwards Andrea L. , Reyes Francis E. , Héroux Annie , Batey Robert T.
Published: September 2010

S-adenosyl-(L)-homocysteine (SAH) riboswitches are regulatory elements found in bacterial mRNAs that up-regulate genes involved in theS-adenosyl-(L)-methionine (SAM) regeneration cycle. To understand the structural basis of SAH-dependent regulation by RNA, we have solved the structure of its metabolite-binding domain in complex with SAH. This structure reveals an unusual pseudoknot topology that creates a shallow groove on the surface of the RNA that binds SAH primarily through interactions with the adenine ring and methionine main chain atoms and discriminates against SAM through a steric mechanism. Chemical probing and calorimetric analysis indicate that the unliganded RNA can access bound-like conformations that are significantly stabilized by SAH to direct folding of the downstream regulatory switch. Strikingly, we find that metabolites bearing an adenine ring, including ATP, bind this aptamer with sufficiently high affinity such that normal intracellular concentrations of these compounds may influence regulation of the riboswitch.