Modelling the Evolution and Spread of HIV Immune Escape Mutants.

During infection with human immunodeficiency virus (HIV), immune pressure from cytotoxic T-lymphocytes (CTLs) selects for viral mutants that confer escape from CTL recognition. These escape variants can be transmitted between individuals where, depending upon their cost to viral fitness and the CTL responses made by the recipient, they may revert. The rates of within-host evolution and their concordant impact upon the rate of spread of escape mutants at the population level are uncertain. Here we present a mathematical model of within-host evolution of escape mutants, transmission of these variants between hosts and subsequent reversion in new hosts. The model is an extension of the well-known SI model of disease transmission and includes three further parameters that describe host immunogenetic heterogeneity and rates of within host viral evolution. We use the model to explain why some escape mutants appear to have stable prevalence whilst others are spreading through the population. Further, we use it to compare diverse datasets on CTL escape, highlighting where different sources agree or disagree on within-host evolutionary rates. The several dozen CTL epitopes we survey from HIV-1 gag, RT and nef reveal a relatively sedate rate of evolution with average rates of escape measured in years and reversion in decades. For many epitopes in HIV, occasional rapid within-host evolution is not reflected in fast evolution at the population level.

Toward 'Complexics' as a transdiscipline

The proposed transdisciplinary field of ‘complexics’ would bring together allcontemporary efforts in any specific disciplines or by any researchersspecifically devoted to constructing tools, procedures, models and conceptsintended for transversal application that are aimed at understanding andexplaining the most interwoven and dynamic phenomena of reality. Our aimneeds to be, as Morin says, not “to reduce complexity to simplicity, [but] totranslate complexity into theory”.New tools for the conception, apprehension and treatment of the data ofexperience will need to be devised to complement existing ones and toenable us to make headway toward practices that better fit complexictheories. New mathematical and computational contributions have alreadycontinued to grow in number, thanks primarily to scholars in statisticalphysics and computer science, who are now taking an interest in social andeconomic phenomena.Certainly, these methodological innovations put into question and againmake us take note of the excessive separation between the training receivedby researchers in the ‘sciences’ and in the ‘arts’. Closer collaborationbetween these two subsets would, in all likelihood, be much moreenergising and creative than their current mutual distance. Humancomplexics must be seen as multi-methodological, insofar as necessarycombining quantitative-computation methodologies and more qualitativemethodologies aimed at understanding the mental and emotional world ofpeople.In the final analysis, however, models always have a narrative runningbehind them that reflects the attempts of a human being to understand theworld, and models are always interpreted on that basis.

Toward 'Complexics' as a transdiscipline

The proposed transdisciplinary field of ‘complexics’ would bring together allcontemporary efforts in any specific disciplines or by any researchersspecifically devoted to constructing tools, procedures, models and conceptsintended for transversal application that are aimed at understanding andexplaining the most interwoven and dynamic phenomena of reality. Our aimneeds to be, as Morin says, not “to reduce complexity to simplicity, [but] totranslate complexity into theory”.New tools for the conception, apprehension and treatment of the data ofexperience will need to be devised to complement existing ones and toenable us to make headway toward practices that better fit complexictheories. New mathematical and computational contributions have alreadycontinued to grow in number, thanks primarily to scholars in statisticalphysics and computer science, who are now taking an interest in social andeconomic phenomena.Certainly, these methodological innovations put into question and againmake us take note of the excessive separation between the training receivedby researchers in the ‘sciences’ and in the ‘arts’. Closer collaborationbetween these two subsets would, in all likelihood, be much moreenergising and creative than their current mutual distance. Humancomplexics must be seen as multi-methodological, insofar as necessarycombining quantitative-computation methodologies and more qualitativemethodologies aimed at understanding the mental and emotional world ofpeople.In the final analysis, however, models always have a narrative runningbehind them that reflects the attempts of a human being to understand theworld, and models are always interpreted on that basis.

The maximum voltage drop in an on-chip power distribution network: analysis of square, triangular and hexagonal power pad arrangements

A mathematical model of the voltage drop which arises in on-chip power distribution networks is used to compare the maximum voltage drop in the case of different geometric arrangements of the pads supplying power to the chip. These include the square or Manhattan power pad arrangement, which currently predominates, as well as equilateral triangular and hexagonal arrangements. In agreement with the findings in the literature and with physical and SPICE models, the equilateral triangular power pad arrangement is found to minimize the maximum voltage drop. This headline finding is a consequence of relatively simple formulas for the voltage drop, with explicit error bounds, which are established using complex analysis techniques, and elliptic functions in particular.

Fraseologia espanyola d'origen llatí i motiu grecorromà

Proyecto realizado en la Universidad de Lleida entre 2003 i 2006. El objetivo principal de este trabajo es vislumbrar la génesis y la evolución de unidades fraseológicas que proceden del latín y de las que utilizan algún motivo grecorromano para su creación. Una de las razones por las que se ha elegido este tipo de fraseologismos es que se remontan a una época bastante bien conocida de la historia de nuestro pueblo, circunstancia que permitirá desarrollar el segundo objetivo, a saber: conocer qué aspectos de la sociedad y la cultura clásicas han sido seleccionados por los antiguos y por los hispanohablantes para la formación de una expresión figurada, así como sacar a la luz las posibles causas que han motivado esta elección. La inclusión de estos dos grupos de unidades –el de las que proceden directamente del latín y el de las que se han basado, ya en plena época romance, en un motivo de la cultura clásica– nos posibilita la consecución de un tercer objetivo: saber si en ambos pueblos (grecorromano e hispano) han llamado la atención los mismos aspectos de la realidad (y de idéntico modo) para la cristalización de unidades fraseológicas. Las hipótesis de partida eran que, en español, debiera darse tanto la perduración o recreación de unidades latinas y griegas, como la creación de nuevas unidades referidas a aspectos culturales de Grecia y Roma; y que el número de estas unidades debiera ser elevado, puesto que el latín es la lengua de la que deriva el español y la cultura grecorromana es la base de la nuestra. Para el establecimiento del corpus definitivo se han elaborado dos corpora de fraseologismos y refranes (sobre el español y el latín), que han sido debidamente comparados hasta llegar establecer unas 20.000 unidades de origen latino y unas 3.000 de origen clásico .

Two different 3D biogeochemical models for the NW mediterranean sea: validation with Meris data and intercomparison

Report for the scientific sojourn carried out at the University of New South Wales from February to June the 2007. Two different biogeochemical models are coupled to a three dimensional configuration of the Princeton Ocean Model (POM) for the Northwestern Mediterranean Sea (Ahumada and Cruzado, 2007). The first biogeochemical model (BLANES) is the three-dimensional version of the model described by Bahamon and Cruzado (2003) and computes the nitrogen fluxes through six compartments using semi-empirical descriptions of biological processes. The second biogeochemical model (BIOMEC) is the biomechanical NPZD model described in Baird et al. (2004), which uses a combination of physiological and physical descriptions to quantify the rates of planktonic interactions. Physical descriptions include, for example, the diffusion of nutrients to phytoplankton cells and the encounter rate of predators and prey. The link between physical and biogeochemical processes in both models is expressed by the advection-diffusion of the non-conservative tracers. The similarities in the mathematical formulation of the biogeochemical processes in the two models are exploited to determine the parameter set for the biomechanical model that best fits the parameter set used in the first model. Three years of integration have been carried out for each model to reach the so called perpetual year run for biogeochemical conditions. Outputs from both models are averaged monthly and then compared to remote sensing images obtained from sensor MERIS for chlorophyll.

Estudi del sistema de constructes en dones víctimes de violència de gènere

Mitjançant les seves experiències, els éssers humans aprenen a construir significats amb els quals donar sentit i organitzar l’entorn físic i social en què es troben immersos. No accedeixen a una realitat vertadera i única sinó que són possibles múltiples construccions de la realitat. Per tant, és necessari elaborar hipòtesis sobre un mateix, els altres i l'entorn. Aquestes hipòtesis personals estan constituïdes per dimensions de significat o constructes, que consisteixen en la captació d’una diferència o en un contrast; implica percebre una discrepància, que s’expressarà en dos pols oposats. Per exemple, construir el significat “fort” implica diferenciar-lo del significat “feble”; a partir d’aquesta dimensió “fort–feble” s'organitzen les experiències classificant-les al llarg d’aquest continuum. Els constructes s’integren en una xarxa constituïnt un sistema. L’experiència clínica evidencia sovint que dones maltractades no reconeixen la violència de gènere. L’experiència d’abús ha de ser detectada, construïda i integrada dins del món dels significats, és a dir, dels constructes, per ser identificada com a tal. Per exemple, és necessari construir la noció d’agressor i de víctima per poder posicionar-hi a un mateix i als altres. L’objectiu d’aquest estudi és explorar el sistema de constructes en dones que pateixen o han patit violència de gènere, centrant-se en la construcció personal de l’abús per identificar els seus constructes i detectar possibles motius que bloquegin el trencament de la relació amb el maltractador o altres possibles solucions. La mostra està constituïda per 36 dones, amb un rang d’edat situat entre els 18 i els 72 anys. La mitjana d’edat es troba al voltant dels 45 anys. La durada d’aquest estudi és de març de 2006 a març de 2007.

Temperament in Bach’s Well-tempered clavier: a historical survey and a new evaluation according to dissonance theory

After a historical survey of temperament in Bach’s Well-Tempered Clavier by Johann Sebastian Bach, an analysis of the work has been made by applying a number of historical good temperaments as well as some recent proposals. The results obtained show that the global dissonance for all preludes and fugues in major keys can be minimized using the Kirnberger II temperament. The method of analysis used for this research is based on the mathematical theories of sensory dissonance, which have been developed by authors such as Hermann Ludwig Ferdinand von Helmholtz, Harry Partch, Reinier Plomp, Willem J. M. Levelt and William A. Sethares

L’impacte de les institucions internacionals sobre la Unió Europea: presa de decisions, integració i europeïtzació

Projecte de recerca elaborat a partir d’una estada a la Center for European Integration de la Freie Universität Berlin, Alemania, entre 2007 i 2009. El tema central del projecte consisteix en la descripció matemàtica de processos espai-temporals mitjançant la teoria dels Continuous-Time Random Walks. L'aportació més significativa del nostre treball en aquest camp consisteix en considerar per primera vegada la interacció entre diversos processos actuant de manera acoblada, ja que fins ara els models existents es limitaven a l'estudi de processos individuals o independents. Aquesta idea fa possible, per exemple, plantejar un sistema de transport en l'espai i a la vegada un procés de reacció (una reacció química, per exemple), i estudiar estadísticament com cada un pot alterar el comportament de l'altre. Això suposa un salt qualitatiu important en la descripció de processos de reacció-dispersió, ja que els nostres models permeten incorporar patrons de dispersió i comportaments temporals (cicles de vida) força realistes en comparació amb els models convencionals. Per tal de completar aquest treball teòric ha estat necessari també desenvolupar algunes eines numèriques (models de xarxa) per facilitar la implementació dels models. En la vessant pràctica, hem aplicat aquestes idees al cas de la dinàmica entre virus i el sistema immunològic que té lloc quan es produeix una infecció a l'organisme. Diferents estudis experimentals portats a terme els últims anys mostren com la resposta immunològica dels organismes superiors presenta una dinàmica temporal força complexa (per exemple, en el cas de la resposta programada). Per aquest motiu, les nostres tècniques matemàtiques són d'especial utilitat per a l'anàlisi d'aquests sistemes. Finalment, altres possibles aplicacions dels models, com ara l'estudi d'invasions biològiques, també han estat considerades.

La construcció del funcionari. Un estudi de cas : INSS Barcelona

El treballador públic és sotmès, des que comença la seva particular relació laboral, a un món fortament estructurat i amb una cultura, unes característiques i un tarannà propis i particulars. És en aquest procés que les forces socialitzadores del seu lloc de treball, juntament amb les del món exterior, el van formant com a treballador públic, fins al punt que es pot parlar del funcionari com d'una construcció. Això produeix una manera de veure i entendre el món laboral molt diferent de la que es té en l'empresa privada. Així, les aptituds, les actituds, les maneres de fer, les dèries i les manies només tenen sentit dins el seu entorn, que ell mateix comprèn com a totalment diferent. L'oposició com a ritual de pas, la socialització secundària, la percepció de l'alteritat, el qui és l'altre, el quan i el perquè, i els trets de la seva cultura - el temps, el treball, la normativa són algunes de les claus estudiades en aquest treball que ens ajuden a comprendre el perquè i el com d'aquesta construcció.

Análisis del comportamiento de los resultados en 'full' y 'direct costing'

In this paper we perform a mathematical analyse of profits and losses indirect and full costing. They are compared in different situations, mainlythe utilisation of productive capacity and the existence of beginninginventories. Direct costing was conceived as a system of cost accountingwhich would show profits as a function of sales. In full costing profitsdepend on available combinations of sales, production, costs of beginninginventories, etc., and information displayed in financial statements displayappears incongruent. Differences in profits with full and direct costingincrease when full costing allocates fixed costs according to normalproduction, in some cases differences, and financial statements would showmore incongruent performance. It is concluded about the importance thatprofit and loss statement expresses profits in both costing systems.

La caverna de Josep Palau i Fabre (1952-1969): teatre versus al·legoria filosòfica per a representar i impedir el final tràgic i fosc del lluminós art de pensar.

What is the use of performing the myth of the cave from book VII of the Republic by Plato? Josep Palau i Fabre, considers that, in Plato's dialogues, the speakers are mere instruments at the service of his dialectical goal. The aim of this article is to show how, by turning the myth into a tragedy and also by relying on Heraclitus's conflict or war of opposites, the playwright succeeds in favoring a sort of thought which is not one-sided or univocal. On the contrary, in Palau i Fabre's La Caverna, the tragic hero, that is, the released prisoner transformed by the light of Reality and finally killed by his "cavemates" -after having been imprisoned again and having tried to rescue them from their ignorance or shadows-, still leaves to them his powerful experience of the agonistikos thought, which might bear fruit in their life to come.

La caverna de Josep Palau i Fabre (1952-1969): teatro versus alegoría filosófica para representar e impedir el final trágico y sombrío del luminoso arte de pensar.

What is the use of performing the myth of the cave from book VII of the Republic by Plato? Josep Palau i Fabre, considers that, in Plato's dialogues, the speakers are mere instruments at the service of his dialectical goal. The aim of this article is to show how, by turning the myth into a tragedy and also by relying on Heraclitus's conflict or war of opposites, the playwright succeeds in favoring a sort of thought which is not one-sided or univocal. On the contrary, in Palau i Fabre's La Caverna, the tragic hero, that is, the released prisoner transformed by the light of Reality and finally killed by his "cavemates" -after having been imprisoned again and having tried to rescue them from their ignorance or shadows-, still leaves to them his powerful experience of the agonistikos thought, which might bear fruit in their life to come.

Greek misogynist tradition in Andreas Capellanus's De amore

The title of this brief article quite clearly illustrates its aims and evident limitations. In principle, a search for a Greek basis of the misogynist content of Andreas Capellanus's De amore is likely to lead researchers to focus on analysis of the sources -Greek sources, of course. However, there is no doubt that Ovid, the most frequently quoted ancient author, in this case the structural source, above all his Ars Amatoria, Remedia Amoris and Heroides, which is quite logical in light of the remarkable presence and influence of Ovid's works throughout that time. There was also a good knowledge of the works of Cicero, Virgil, Horace and Juvenal. However, other classical authors, even the Greeks -those who were known then-, were undoubtedly read in the schools, but the knowledge of their works was certainly superficial. Furthermore, given the scholastic method followed in De amore, it would be absurd not to consider the use of many quotations that appeared in the Compendia and in handbooks of religious instruction.

Complexitat i fenomen (socio)linguístic

Intermediate phenomena of reality present particular characteristics of systemic self-organization, multilevel interrelations, recursivity, emergence of new «objects» with properties different from those of the elements that form them, and evolutionary dynamics, that probably need the formulation of new theoretical concepts and different paradigm principles. The sciences or perspectives of complexity, or the «complex» thinking, try to respond adequately to this complexity of reality. This approach adopts a multidimensional, integrated and dynamic view of reality: the world is made up of overlapping levels of different elements which produce new properties or new organizations at higher levels. If we conceive what we call languages as simple and decontextualized objects, we can understand some of the more mechanical aspects but we will ignore their conditions of existence, functionality, maintenance, variation, change and extinction.