Versatile Character Research Articles

Le vagabond et ses avatars chez Apollinaire

Passionate about mundane details and singular beings, Apollinaire deploys throughout his stories and novels quite a collection of mysterious and paradoxical characters. A central place in his collection is occupied by the wanderer which illustrates the propensity of the writer towards the occult and the picturesque, towards the anecdotal and the extraordinary. As a being always on the run he is sometimes associated with a bohemian spectator, jouisseur of the street and sometimes a marginal presence bordering on antisocial. Versatile character, the apollinarian wanderer does not refer to a specific social type. Wanderer, bohemian, chiffonnier, antique dealer, he has a rather metaphorical position that allows him to expose multiple identities at once. His multivalent nature makes it difficult for a true literary taxonomy. Always seeking innovation and surprise, Apollinaire was able to refine the ambivalence of the wanderer and often relates it to the image of the artist. Marginal and mystifying, the apollinarian wanderer is yet lacking any pejorative sense because its uniqueness is only a sign of originality. With its attractive heterogeneity, the apollinarian prose creates a vast and fine repertoire with a wanderer who is constantly redefining the concept of wandering. With its multiple facets, it actually becomes a living metaphor of a work that is looking through a hybrid and plural writing, mixing genres and composite images. Exploring the prose of Apollinaire, however, we can detect multiple lines of coherence that ultimately reveal a rich array of the wanderer. Despite the nature of the chameleonic apollinarian wanderer, our challenge is to analyze his literary metamorphoses and thus arrive at a definition that surprises in its many urban disguises.

Structural and electronic properties of GeTe under pressure: ab initio study

The versatile phase transition character and associated intriguing electronic properties of germanium telluride (GeTe) have attracted intense interests from both academic and industrial perspectives. At ambient pressure, GeTe falls into a rhombohedral structure. With hydrostatic pressure applied, the rhombohedral R3mH GeTe transforms into NaCl (B1) structure at 3·2 GPa, and at 34·3 GPa, it transforms into CsCl (B2) structure. Diverse phase transitions under pressure lead to significant modulations in energy band gaps, which is still not clear. The aim of this research is to investigate the energy band gap of GeTe under pressure. Using first principles calculations, the proposed research investigates the structural phase transition and corresponding electronic energy band behaviour of GeTe under pressure. From the energy band structure analysis, it was found that the B2 phase is metallic, while the B1 and R3mH phases possess a narrow band gap at the equilibrium state. With pressure applied, the insulating gaps of both structures close gradually under positive pressure and enlarge upon negative pressure. The novel aspect of this work is the modulation of energy band gaps by mechanical pressure. The predicted band gaps can change over a wide range, which suggests possible and efficient electronic property modulation using external pressure. Furthermore, these findings are helpful in predicting the structural stability and optical band gap associated performance in GeTe based advanced materials under pressure.

ON THE VERSATILITY OF VON WILLEBRAND FACTOR

Von Willebrand factor (VWF) is a large multimeric protein, the function of which has been demonstrated to be pivotal to the haemostatic system. Indeed, quantitative and/or qualitative abnormalities of VWF are associated with the bleeding disorder Von Willebrand disease (VWD). Moreover, increased plasma concentrations of VWF have been linked to an increased risk for thrombotic complications. In the previous decades, many studies have contributed to our understanding of how VWF is connected to the haemostatic system, particularly with regard to structure-function relationships. Interactive sites for important ligands of VWF (such as factor VIII, collagen, glycoprotein Ibα, integrin αIIbβ3 and protease ADAMTS13) have been identified, and mutagenesis studies have confirmed the physiological relevance of the interactions between VWF and these ligands. However, we have also become aware that VWF has a more versatile character than previously thought, given its potential role in various non-hemostatic processes, like intimal thickening, tumor cell apoptosis and inflammatory processes. In the presence review, a summary of our knowledge on VWF structure-function relationships is provided in the context of the “classical” haemostatic task of VWF and in perspective of pathological processes beyond haemostasis.

Cutaneous dendritic cells in allergic inflammation

The skin represents a physical barrier, which is capable of protecting the body from damaging invaders. Moreover, the skin operates as an active immunological organ, harbouring a complex network of dendritic cells (DCs), which serve as a bridge between innate and adaptive immunity. Equipped with specific pattern recognition receptors (PRRs), DCs are able to capture, process and present antigens to naïve T cells in the skin draining lymph nodes, thereby inducing adaptive antigen-specific immunity. However, the outcome of the immune response is shaped by numerous factors including the DC subtype, maturation state of DCs, composition of PRRs expressed by DCs, type of pathogen as well as factors in the microenvironment. Thus, cutaneous DC subtypes are known to contribute to both, peripheral tolerance and the generation of allergic skin inflammation. Identifying the underlying mechanisms is a challenging task in understanding DC biology. Based on their functional diversity, cutaneous DCs might represent promising therapeutic targets, with the potential of down-modulating pro-inflammatory immune responses and inducing tolerogenic pathways, thereby ensuring the maintenance of tissue homeostasis and restoring the balance of dysregulated immune reactions in the context of allergic skin diseases. In this review, we summarize the versatile character of DC subtypes in human skin and highlight their phenotypic characteristics and role in allergic skin inflammation. In addition, we discuss current therapeutic approaches for the management of inflammatory skin diseases such as atopic dermatitis with the main focus on strategies targeting DCs. We point towards potential challenges, benefits, risks and limitations for the treatment of patients.

Hydrogen species within the metals: Role of molecular hydrogen ion H2+

AbstractNovel mechanism of hydrogen interaction with transition metals via stepwise reversible dissociative ionization of H2 molecule is proposed instead of a commonly accepted dissociative adsorption. It involves ionization of H2 to molecular ion (H2+)ad on the outer surface of metal phase, its subsequent absorption and dissociation within the metal phase into (H+)ab ions, i.e., absorbed protons, as described by: H2⇄(H2+)ad+e− and (H2+)ad⇄(H2+)ab⇄2(H+)ab+e−. Absorption here is treated as adsorption on the inner surface of the tetrahedral and octahedral voids within metal lattice. The mechanism is based on the first principles and explains consistently the dependence of mechanical properties of metals on the amount of absorbed hydrogen as well as the mechanism of hydrogenation and hydrogen transport through the metals. The proposed dissociative ionization mechanism is well supported by thermodynamic and steric arguments. In the case of noble metals the presented mechanism carries versatile character as it is valid for both gaseous phase and aqueous solutions.

Highly efficient and straightforward functionalization of cellulose films with thiol-ene click chemistry

Three efficient and straightforward chemical pathways have been studied to functionalize solid cellulose substrates, involving for the first time alkoxysilane chemistry coupled with the photochemical version of the thiol-ene reaction. The success of the reactions was confirmed using FTIR-ATR spectroscopy and XPS analysis, but different grafting efficiencies were observed depending on the combination used. In a first route, ene-functionalized cellulose films were synthesized using vinyltrimethoxysilane as coupling agent, and were photochemically coupled with methylthioglycolate (MeGlySH). A very fast reaction rate was observed for this reaction during the first 5 min. In a second route, the opposite reaction was envisaged by clicking allylbutyrate on a thiol-functionalized cellulose surface, previously synthesized using 3-mercaptopryltrimethoxysilane as coupling agent. The success of the reaction was highlighted, but lower modification rates were observed. In a third route, a novel approach was successfully proposed for the grafting of thiol molecules on cellulose, based on the click derivatization of the molecule with alkoxysilane functions. Through this study, we expand the modular and versatile character of click chemistry to natural cellulosic substrates. But most importantly, these modification routes can be envisaged for the functionalization of other surfaces (i.e., metal alkoxides for instance) where alkoxysilane chemistry can be employed.

Crucial Role for Insertion Sequence Elements in Lactobacillus helveticus Evolution as Revealed by Interstrain Genomic Comparison

Lactobacillus helveticus is a versatile dairy bacterium found to possess heterogeneous genotypes depending on the ecosystem from which it was isolated. The recently published genome sequence showed the remarkable flexibility of its structure, demonstrated by a substantial level of insertion sequence (IS) element expansion in association with massive gene decay. To assess this diversity and examine the level of genome plasticity within the L. helveticus species, an array-based comparative genome hybridization (aCGH) experiment was designed in which 10 strains were analyzed. The aCGH experiment revealed 16 clusters of open reading frames (ORFs) flanked by IS elements. Four of these ORFs are associated with restriction/modification which may have played a role in accelerated evolution of strains in a commercially intensive ecosystem undoubtedly challenged through successive phage attack. Furthermore, analysis of the IS-flanked clusters demonstrated that the most frequently encountered ISs were also those most abundant in the genome (IS1201, ISL2, ISLhe1, ISLhe2, ISLhe65, and ISLhe63). These findings contribute to the overall viewpoint of the versatile character of IS elements and the role they may play in bacterial genome plasticity.

Polyethylene Nanocomposite Heat‐Sealants with a Versatile Peelable Character

Polyethylene Nanocomposite Heat‐Sealants with a Versatile Peelable Character

CLINIC-IMMUNOLOGICAL FEATURES OF CHRONIC RECURREN PURULENT INFECTIONS OF THE SKIN

The analysis of clinic-laboratory parameters of 73 patients with chronic purulent inflammatory diseases of the skin during the remission of the basic disease was carried out. At 31,5 % of patients in the samples from the pharynx S.aureus was revealed in diagnostically significant amount. Also in such patients accompanying chronic infections significantly more often were marked (р = 0,022), relative amount of B-lymphocytes and concentration of IgA in blood were decreased. Changes in the immunorgamme had a versatile character and concerned mainly humoral immunity.

Calcium croconate and calcium oxalato-croconate complexes with 2D and 3D crystal structures

Two novel complexes of calcium croconate Ca(μ 3-C 5O 5)(H 2O) 3 ( I) and calcium oxalato-croconate Ca 2(μ 4-C 5O 5)(μ 6-C 2O 4)(H 2O) ( II) have been synthesized by soft chemical routes and their crystal structures have been solved from single-crystal data. Croconates I and II crystallize in orthorhombic space groups Pbca and Pnma, respectively. Their crystal structures evidence the versatile character of the croconate anion in the framework design. The calcium croconate I displays a 2D structure with corrugated sheets formed by croconate dianions and eightfold coordinated calcium atoms within [Ca 2O 14] dimers. The sheets develop eight-member apertures made of four dimers and four croconate dianions. The structure of II displays a 3D open-framework built from layers connected to each other by croconate dianions. This arrangement generates rectangular cavities free of water molecules. Seven- and eightfold coordinated calcium atoms with oxalate dianions constitute the layers. In both structures, the connecting modes of croconates are unusual. The thermal behaviour study has demonstrated that II is stable until 380 °C.

Rigorous ADI‐FDTD analysis of left‐handed metamaterials in optimally‐designed EMC applications

PurposeThe paper seeks to investigate the precise time‐domain modelling and broadband performance optimisation of 3D EMC structures formed by composite left‐handed metamaterials.Design/methodology/approachA frequency‐dependent alternating‐direction implicit finite‐difference time‐domain method is introduced. Developing a class of multi‐directional curvilinear schemes for double‐negative media, the unconditionally stable algorithm forms robust lattice tessellations and provides advanced models complicated media interfaces. Moreover, the erroneous refractions at the metamaterial boundaries are systematically analysed through dynamic stencil configurations and powerful perfectly matched layer absorbers.FindingsThe paper finds that the proposed technique leads to convergent discretisations that resolve all propagation bandwidths and enhances the design of promising periodical devices loaded by substrates of thin wires and split‐ring resonators. Furthermore, its versatile character subdues dispersion deficiencies far beyond the usual stability criteria. Numerical validation, addressing various up‐to‐date EMC devices like coupled antennas, waveguides, high‐pass filters and absorber linings in test facilities, confirms the merits of the algorithm.Originality/valueThe novel methodology offers an advanced nodal control process which drastically suppresses the serious dispersion errors of existing approaches as time‐step exceeds the Courant limit. The resulting grids can support coarse resolutions, while the general curvilinear framework, along with the ADI rationale, allows the accurate approximation of demanding permittivity and permeability constitutive profiles. Hence, high accuracy and confined computational overhead are achieved without the need of laborious assumptions.

Experiences with IWRM in the Central Asia and Caucasus Regions

The Soviet period of the command system left a legacy of under-funded multilevel bureaucratic structure of water administration and planning for the Central Asia and Caucasus countries. The existing administrative system of water management is unable to cope with inter-sector, dynamic, and versatile character of current water management problems. Therefore, the situation calls for principles of integrated water resources management (IWRM) in the region. This paper presents some ideas about institutional reforms in water sector started in Central Asia and Caucasus regions. It describes the key IWRM principles and how these principles are being implemented into practice.

Catalysis by Hydrotalcites and Related Materials

AbstractFor Abstract see ChemInform Abstract in Full Text.

Catalysis by Hydrotalcites and Related Materials

Catalytic applications of Layered Double Hydroxides (LDH) or anionic clays have for a long time focused on the condensation reactions carried out with mixed oxides obtained by calcinations of Mg/Al LDH. However, the versatile character of materials prepared from these LDH exhibiting Lewis or Bronsted type basic sites has recently been underlined, and led us to contemplate extended applications in clean industrial processes. Moreover, due to their wide variety of compositions, LDH are also attractive precursors of multicomponent nanostructured catalysts. They give rise to supported metal catalysts whose metal support interaction and cooperation can be fine-tuned, as illustrated in pertinent case studies such as the hydrogenation of nitriles and the “one-pot” synthesis of methyl isobutyl ketone from acetone.

Religious Discourse and Cyberspace

This article explores the evolution and development of a typology of cyberspatial religious discourse over the course of a few years. The vast quantity of information published on the Net requires the creation of a typology in order to identify and classify the different approaches, attitudes, applications and functions of religion on and in cyberspace. The three different typologies indicate, on the one hand, the versatile character of cyberspace, and on the other hand, the ever-expanding nature of its perimeters. They show that cyberspatial discourse, religious or not, cannot be confined within restricted boundaries but must be perceived as a changeable and unforeseen structure, having the capacity to adapt itself according to the visions, fantasies, ingenuities and inventiveness of the users. They also suggest that despite the rhizomatic construction of cyberspace, the information published on the innumerable religious sites can be systematised in a ‘logical’ formation.

ON THE PERFORMANCE OF VARIABLE GEOMETRY MANIPULATORS: PART I – THREE DIMENSIONAL ORDER N FORMULATION

A relatively general formulation for studying dynamics and control of a novel multi-module mobile manipulator, with slewing as well as deployable links, is presented. The deployment character leads to several advantages including reduced coupling, fewer singular configurations and ease of obstacle avoidance. The three-dimensional, order N, Lagrangian approach accounts for interactions between orbital, librational, slew, deployment and elastic degrees of freedom. The versatile character of the formulation makes it applicable to a large class of manipulator systems of contemporary interest. Of particular significance is the order N property which promises considerable saving in computational cost.

Application of the versatile character of the tellurium atom for the synthesis of C-nucleoside analogues via sugar tellurides

Making use of the versatile character of the tellurium atom such as its radicophilicity, nucleophilicity and electrophilicity, D-ribofuranosyl, 2-deoxy-D-ribofuranosyl and D-glucosyl p-methoxyphenyl tellurides have been prepared. Under suitable conditions, the corresponding anomeric radical, anomeric cation and anomeric anion, respectively, are formed from the sugar tellurides. By the following coupling reactions of the anomeric radical and anomeric cation to electron-poor and electron-rich aromatics, respectively, the corresponding C-nucleoside analogues have been synthesized in moderate yields. The anomeric anion has also been trapped by an electrophile such as benzaldehyde.

A spatial habitat model for the marsh-breeding red-winged blackbird ( Agelaius phoeniceus L.) in coastal Lake Erie wetlands

A spatial model was developed to predict the distribution of a marsh-nesting bird species, red-winged blackbird ( Agelaius phoeniceus L.) in Lake Erie coastal wetlands. The study site was in two diked wetland basins in Ottawa County, Ohio, USA. Geographic Information System (GIS) was used for data handling, storage, analyzing and running the model. Nests of birds were located, and vegetation durability, vegetation height, vegetation density, water depth, open water and structural aspects of the study basins were quantified by low altitude aerial photography and extensive field work for ground truthing. Spatial variables such as distance to open water edge, distance to wetlands edge, and friction maps by spread over depth and stem density for simulating predator access to wetlands were generated using the GIS. Model variables and coefficients were determined using logistic regression. Vegetation durability, distance to open water and depth of water significantly ( P < 0.01) affected the nesting outcome. Results show that the probability of a bird nesting in a location within a marsh increased with increasing vegetation durability, water depth, and with decreasing distance to open water edge. Model verification and validation indicated that the model did not show any interspecific interactions or clumping of nest sites defined by behavioral constraints. Results were in accordance with the conclusions of previous studies looking at breeding success of red-winged blackbird. This study validated the processes affecting nest site selection of red-winged blackbirds with extensive data and statistical analyses. The methodology and versatile character of the GIS-based spatial model enables adaptations to any other marsh-nesting bird species and geographic area. Data needed for the model are relatively easy to obtain and the model provides micro-habitat scale results that can be used by wetland conservationists and managers.

Quantitative flow analysis around aquatic animals using laser sheet particle image velocimetry

Two alternative particle image velocimetry (PIV) methods have been developed, applying laser light sheet illumination of particle-seeded flows around marine organisms. Successive video images, recorded perpendicular to a light sheet parallel to the main stream, were digitized and processed to map the flow velocity in two-dimensional planes. In particle tracking velocimetry (PTV), displacements of single particles in two subsequent images were determined semi-automatically, resulting in flow diagrams consisting of non-uniformly distributed velocity vectors. Application of grid-cell averaging resulted in flow field diagrams with uniform vector distribution. In sub-image correlation PIV (SCPIV), repetitive convolution filtering of small sub-areas of two subsequent images resulted in automatic determination of cross-correlation peaks, yielding flow field diagrams with regularly spaced velocity vectors. In both PTV and SCPIV, missing values, caused by incomplete particle displacement information in some areas of the images or due to rejection of some erroneous vectors by the vector validation procedure, were interpolated using a two-dimensional spline interpolation technique. The resultant vector flow fields were used to study the spatial distribution of velocity, spatial acceleration, vorticity, strain and shear. These flow fields could also be used to test for flow in the third dimension by studying the divergence, and to detect the presence and location of vortices. The results offer detailed quantitative descriptions of the flow morphology and can be used to assess dissipated energy. The versatile character of the technique makes it applicable to a wide range of fluid mechanical subjects within biological research. So far it has been successfully applied to map the flow around swimming copepods, fish larvae and juvenile fish and the ventilation current of a tube-living shrimp.

Walter Gordy: some memories and impressions

With the death of Walter Gordy it was clear to many physicists and chemists, and especially to those who knew him as a person, that the world of radiospectroscopy and molecular physics had lost one of its more versatile and colourful characters. For something like thirty years he was the dominant figure in the quest for scientifically usable radio waves at the shortest possible wavelengths, an objective which he pursued with dramatic success and with relentless energy. For a more complete picture of the man, however, we must also look into the ways in which this energy was also directed into various other areas of physics and chemistry. A scientist’s first research, and how he or she describes it, can often give keys to the person’s general approach to scientific problems, and indeed can often show a pattern of interests to be sustained over a long period. This applies in some degree to Gordy, but an examination of his early work leaves us aware, not for the only time, that generalizations such as that above do not apply well to him. Beginning in 1934 and continuing through the remainder of that decade, Gordy’s early publications were of infra-red spectroscopic studies of liquids and solutions. The early work was associated with the names of E.K. Plyler and Dudley Williams, at the Physics Department of the University of North Carolina, and continued in the later part of this period when Gordy was at the Mary Hardin-Baylor College in Belton, Texas. Perhaps it was during this time that he, a Southerner by birth and to some extent by temperament, became what he once described to me as “a Texas fan”. The frontier spirit of that state no doubt suited his approach to science and to life. In some thirty papers up to 1941, Gordy’s work shows a strong awareness of chemical bonding and structure. Mostly this was in relation to molecular interactions in liquids, particularly hydrogen bonding, spectroscopic studies of which were becoming recognized [ 11 as a very direct means to new clear-cut