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A Compendium of Urinary Biomarkers Indicative of Glomerular Podocytopathy
It is well known that glomerular podocyte injury and loss are present in numerous nephropathies and that the pathophysiologic consecution of disease hinges upon the fate of the podocyte. While multiple factors play a hand in glomerulopathy progression, basic logic lends that if one monitors the podocyte's status, that may reflect the status of disease. Recent investigations have focused on what one can elucidate from the noninvasive collection of urine, and have proven that certain, specific biomarkers of podocytes can be readily identified via varying techniques. This paper has brought together all described urinary biomarkers of podocyte injury and is made to provide a concise summary of their utility and testing in laboratory and clinical theatres. While promising in the potential that they hold as tools for clinicians and investigators, the described biomarkers require further comprehensive vetting in the form of larger clinical trials and studies that would give their value true weight. These urinary biomarkers are put forth as novel indicators of glomerular disease presence, disease progression, and therapeutic efficacy that in some cases may be more advantageous than the established parameters/measures currently used in practice
Early Stage Cavitation Erosion within Ceramics: An Experimental Investigation
Six ceramic material types were considered within an experimental investigation to identify the erosion damages mechanisms resulting from cavitation exposure. These materials were a Y-TZP type of zirconia, different commercially available silicon nitrides, a high purity
alumina and an hardened high nitrogen stainless steel. An ultrasonic transducer was utilised to produce cavitation conditions and the configuration was “static specimen method” using a 5mm diameter probe, 20kHz and 50μm of amplitude. The exposure times were periods from
15 seconds to 2 hours. Experimental methods employed to characterise wear mechanisms were light microscopy,
scanning light interferometry, scanning electronic microscopy. It was found that the zirconia and silicon nitrides demonstrated evidence of local pseudoplastic
deformation or depression prior to more pronounced erosion damages by fracture. Zirconia showed evidence of delayed surface changes when the sample is at rest stored in air
possibly by spontaneous phase transformation after the completion of the erosion tests. Alumina showed evidence of brittle surface fracture and negligible or no pseudo-plastic deformation. All wear mechanisms are discussed and the materials are ranked in terms of cavitation resistance performance
Distruzione etnonazionalista della società: il caso della Bosnia
La comprensione dell'identità etnonazionale delle diverse comunità
nell'Europa Centrale ed Orientale è specifica in quanto determinata soprattutto
dall'appartenenza culturale dei vari gruppi etnici, legata in un modo
speciale alle origini confessionali e a quelle linguistiche, che in molti casi trascende
i confini degli stati in questione. Il caso della Bosnia ed Erzegovina è stato scelto perché dimostra in modo
più trasparente la forza devastatrice dell'etnonazionalismo. Se si poteva mettere
in questione l'esistenza dei presupposti per l'integrazione dei popoli
jugoslavi in varie forme di comunità culturale, economica o politica, la Bosnia
ed Erzegovina non poteva essere definita creazione artificiale o di compromesso
da parte di diverse volontà politiche considerato che era una società
altamente integrata
Constituting the Social Basis of the EU: Reflections from the European Margins
The article addresses significant aspects of the constitution of the European Union’s social basis from the broader perspective of a European space under construction. The specific point of view regards the process of Europeanization through enlargement to the post-socialist Eastern and South European countries, and conditionality as its main instrument. In the light of the five-year moratorium proposed by the Juncker Commission in 2015, the process is examined particularly from its margins by considering the case of Bosnia and Herzegovina (BiH), i.e. the last country in the ‘Western Balkans’, together with Kosovo, that is not yet a candidate for EU membership. The analysis aims to shed light on two different and conflictual forms of agency: first, the institution building process through accession procedures; second, social dissent patterns and citizens’ mobilization in Bosnia and Herzegovina. The purpose is to analyze if and how these diverse agencies cross borders and soften boundaries to constitute an emerging European society. A constant methodological concern of this study is if and how an ethnography of the process may contribute to the analysis of European integration in its complex, non-linear and often contradictory nature (Kauppi 2013
Advanced discontinuous integral-equation schemes for the versatile electromagnetic analysis of complex structures
Premi Extraordinari de Doctorat, promoció 2018-2019. Àmbit de les TICLes Equacions Integrals superficials més importants són l'Equació de Camp Elèctric (EFIE), per a l'anàlisi de la dispersió electromagnètica d'objectes conductors perfectes (PEC), i la formulació Poggio–Miller–Chang–Harrington–Wu–Tsai (PMCHWT), orientada a l'anàlisi d'objectes homogenis penetrables. Ambdues són normalment discretitzades, amb el Mètode dels Moments (MoM), amb funcions base div-conformes, dependents de les arestes del mallat. Les discretitzacions div-conformes de les formulacions EFIE i PMCHWT representen esquemes conformes; és a dir, amb solucions convergents a dins de l'espai físic de corrents.
Tanmateix, les implementations MoM div-conformes requereixen que el mallat sigui conforme geomètricament, amb cada parell de triangles adjacents compartint només una aresta. El desenvolupament d'esquemes div-conformes per a objectes compostos amb línies al llarg de les quals tres o més regions hi intersecten, esdevé molt incòmoda perquè cal definir condicions de continuïtat especials en aquestes línies d'intersecció. A més, els mallats que resulten de la juxtaposició de subdominis independentment mallats són típicament no-conformes geomètricament i per tant no aptes per a l'anàlisi div-conforme convencional en Mètode dels Moments. En aquesta Tesi, es tracta l'anàlisi robusta, precisa i versàtil de la dispersió electromagnètica d'objectes conductors o penetrables amb forma arbitrària i d'objectes compostos amb línies d'intersecció entre differents regions, ja sigui amb mallats conformes com no-conformes. Amb aquest objectiu, fem ús de la formulació d'equació integral EFIE–PMCHWT, la qual resulta de l'aplicació de les formulacions EFIE o PMCHWTal llarg de superfícies de contorn, respectivament, incloent regions conductores o separant regions penetrables. Els esquemes proposats en aquesta Tesi es basen en el desenvolupament dels corrents amb conjunts de funcions base discontínues a través de les arestes del mallat i dependents només dels triangles del mallat. Aquesta estratègia dóna lloc a integrals de contorn amb Kernels hypersingulars, que maneguem mitjançant el testeig de les equacions amb funcions de testeig especialment dissenyades, definides fora de les triangulacions de la superfície de contorn, a dins de la regió a on els camps són zero d'acord amb al Teorema d'Equivalència superficial. Les nostres implementacions de la formulació EFIE-PMCHWT, dependents només de triangles, mostren millor precisió respecte dels esquemes continus convencionals en l'anàlisi d'objectes angulosos a on el modelatge acurat del comportament dels camps singulars és d'importància cabdal. A més, els nostres esquemes mostren en general una gran flexibilitat en l'anàlisi d'objectes compostos amb línies d'intersecció entre regions ja que no hi cal el modelatge especial dels corrents. Finalment, les implementacions proposades poden abordar l'anàlisi d'objectes amb forma arbitrària, totalment homogenis o homogenis a trossos, i amb mallats geomètricament no-conformes.The most prominent surface integral equations, the electric field integral equation (EFIE) used for the scattering analysis of perfectly electrically conducting (PEC) targets and the Poggio–Miller–Chang–Harrington–Wu–Tsai (PMCHWT) formulation commonly utilized for the analysis of homogeneous penetrable objects, are usually discretized, in the context of method of moments (MoM), with edge-based divergence-conforming basis functions.
Divergence-conforming discretizations of the EFIE and PMCHWT formulations excel asconforming schemes, hence with converging solutions in the physical space of currents.
However, the divergence-conforming MoM implementations require the underlying mesh to be geometrically conformal, with pairs of adjacent facets sharing a single edge. Thedevelopment of divergence-conforming schemes for composite objects with junctions, viz.boundary lines where more than two regions intersect, becomes somewhat awkward because of the definition of special continuity conditions at junctions. Moreover, the meshes arising from the juxtaposition of independently meshed subdomains in the modular design of complex objects are typically nonconformal and thus not suitable for conventional divergence-conforming MoM schemes.
In this thesis, we address the robust, accurate and versatile scattering analysis of PEC and penetrable objects with arbitrary shape and composite objects with junctions meshed with conformal or nonconformal meshes. For this purpose, we employ the EFIE–PMCHWT integral-equation formulation, which follows from the application of the EFIE or PMCHWT formulations over boundary surfaces, respectively, enclosing PEC regions or separating penetrable regions. The proposed schemes rely on the expansion of the corrents with the facet-based, discontinuous-across-edges basis functions. This choice gives rise to boundary integrals with hypersingular kernels, which we handle by testing the equations with well-suited testing functions defined off the boundary tessellation, inside the region where, in light of the surface equivalence principle, the fields must be zero. Our facet-based EFIE-PMCHWT implementations exhibit improved accuracy when compared with the conventional continuous schemes in the analysis of sharp-edged targets where the accurate modelling of singular fields is of great importance. Moreover, our schemes manifest in general great flexibility in the analysis of composite objects with junctions as the special modelling of currents at junctions is not required. Finally, the proposed implementations can handle geometrically nonconformal meshes when applied to piecewise (or fully) homogeneous arbitrarily shaped objects.Postprint (published version
Constituting the Social Basis of the EU: Reflections from the European Margins
The article addresses significant aspects of the constitution of the European Union’s social basis from the broader perspective of a European space under construction. The specific point of view regards the process of Europeanization through enlargement to the post-socialist Eastern and South European countries, and conditionality as its main instrument. In the light of the five-year moratorium proposed by the Juncker Commission in 2015, the process is examined particularly from its margins by considering the case of Bosnia and Herzegovina (BiH), i.e. the last country in the ‘Western Balkans’, together with Kosovo, that is not yet a candidate for EU membership. The analysis aims to shed light on two different and conflictual forms of agency: first, the institution building process through accession procedures; second, social dissent patterns and citizens’ mobilization in Bosnia and Herzegovina. The purpose is to analyze if and how these diverse agencies cross borders and soften boundaries to constitute an emerging European society. A constant methodological concern of this study is if and how an ethnography of the process may contribute to the analysis of European integration in its complex, non-linear and often contradictory nature (Kauppi 2013
Temporality of the Impossible:exploring the multifaceted process of preparation of complex pieces from the late 20th and 21st centuries
Temporality of the Impossible is a research project about my artistic practice on performing late 20th- and 21st-century solo violin repertoire with multi-dimensional difficulties. Within this repertoire, I focused on pieces that, despite minute-detailed annotations in the score, intentionally escape the extreme fixity that they at first glance seem to be designed to achieve. As such, they impose a novel approach to the interface between performer, instrument, notation, movement, and sound, and thus demand redefining of performance practice and practicing. The challenges begin from the notation and range over destabilased sonic identity of the instrument, extreme combinations and successions of techniques, challenging meanings of physical actions and gestures, and going as far as using the non-linear passing of time and using performance space as part of the musical material. With these kinds of challenges as a starting point, the sounding outcome of each of these pieces can greatly vary from one performance to another. The following thesis is an account of the process, in which my explorations aimed to reexamine, deconstruct, and reconfigure understandings and approaches to the interpretation and performance practice of a classically trained violinist in relation to this chosen repertoire. Through the process of deconstructing and unlearning, I had to develop methodologies that facilitated learning how to retain, navigate, and channel surplus amounts of information which was often contradictory. My main aim was to establish ways that would allow for embodiment of potentials of all the material of the piece individually, rather than fixing one interpretation during the preparation process and thus imposing undesired hierarchy between the material. In this way, the material could continue to evolve and organically build the interpretation always anew in the moment of the performance, according to the design of the pieces. Accepting this continuous process as the necessary tool of the performative vocabulary in the pieces and its protean nature was a significant part of the research. The research outcomes presented here include recordings of performances alongside a detailed account of the process leading to performance. Both the performances and the methodology can feed into current thought on performance practice, and the methodologies could be adopted by other violinists dealing with works from late 20th- and 21st-century solo violin repertoire.
Tangential-normal surface testing for the nonconforming discretization of the electric-field integral equation
©2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.Nonconforming implementations of the electric-field integral equation (EFIE), based on the facet-oriented monopolar-RWG set, impose no continuity constraints in the expansion of the current between adjacent facets. These schemes become more versatile than the traditional edge-oriented schemes, based on the RWG set, because they simplify the management of junctions in composite objects and allow the analysis of nonconformal triangulations. Moreover, for closed moderately small conductors with edges and corners, they show improved accuracy with respect to the conventional RWG-discretization. However, they lead to elaborate numerical schemes because the fields are tested inside the body, near the boundary surface, over volumetric subdomains attached to the surface meshing. In this letter, we present a new nonconforming discretization of the EFIE that results from
testing with RWG functions over pairs of triangles such that one triangle matches one facet of the surface triangulation and the other one is oriented perpendicularly, inside the body. This “tangential-normal” testing scheme, based on surface integrals, simplifies considerably the matrix generation when compared to the volumetrically tested approaches.Peer ReviewedPostprint (author's final draft
CENP-C unwraps the human CENP-A nucleosome through the H2A C-terminal tail
Centromeres are defined epigenetically by nucleosomes containing the histone H3 variant CENP-A, upon which the constitutive centromere-associated network of proteins (CCAN) is built. CENP-C is considered to be a central organizer of the CCAN. We provide new molecular insights into the structure of human CENP-A nucleosomes, in isolation and in complex with the CENP-C central region (CENP-C-CR), the main CENP-A binding module of human CENP-C. We establish that the short alpha N helix of CENP-A promotes DNA flexibility at the nucleosome ends, independently of the sequence it wraps. Furthermore, we show that, in vitro, two regions of human CENP-C (CENP-C-CR and CENP-C-motif) both bind exclusively to the CENP-A nucleosome. We find CENP-C-CR to bind with high affinity due to an extended hydrophobic area made up of CENP-A(V)(532) and CENP-A(V)(533). Importantly, we identify two key conformational changes within the CENP-A nucleosome upon CENP-C binding. First, the loose DNA wrapping of CENP-A nucleosomes is further exacerbated, through destabilization of the H2A C-terminal tail. Second, CENP-C-CR rigidifies the N-terminal tail of H4 in the conformation favoring H4(K20) monomethylation, essential for a functional centromere
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