550 research outputs found
Does our Past have a Motivational Effect? Our Reasons for Acting: Sartreâs Philosophy of Action
The goal of my paper is to consider how one chooses oneâs own action. First, I will try to understand how both his past and his environment can condition someone's action. According to Sartre, we can act without being determined by our past which is always separated from us. It will be important to understand how such a process is possible. Is man completely free to act? Then I will raise the question of our reasons for acting in order to show that reasons do not pre-exist in the world. Motives are always motives for an agent who gives them meaning. They never condition the action completely. By his project, the agent reveals some reasons to act and these reasons have a value only in relation to the project adopted by the agent. Therefore, we can say that everyone is condemned to be free
Subversive subservience' : a comparative study of the responses of Tiyo Soga and Mpambani Mzimba to the Scottish missionary enterprise
Bibliography: leaves 240-253.My thesis is that early African Christians engaged in critical dialogue with their missionary counterparts in a variety of ways and forms which served to challenge and enrich the Christianization process in South Africa, eventually giving rise to the emergence of African Christianity and theologies. My aim is to show that African Christians talked back in the long conversation with the European missionaries, ""a conversation full of arguments of words and images."" ĂÂč Early African Christians used various strategies and ways of responding to the missionary encounter ranging from overt to covert forms of resistance and negotiation. These were related to conditions on the ground. African Christian responses thus contradict any assertion of total conformity to the colonial missionary praxis. The classics debate at Lovedale, for instance, reveals that despite the apparent conformity and obedience to orthodoxy at the official level there was an awareness of ambivalence at a secondary (hidden) level. It is this awareness rather than the obvious ambivalence that is crucial to us
Agir dans lâangoisse ou par habitude ? La libertĂ© de lâagent dans la philosophie existentialiste de Sartre
Lâangoisse est une expĂ©rience de la libertĂ©. Elle est angoisse devant lâavenir et angoisse devant le passĂ©. LâĂȘtre humain vit les possibilitĂ©s dâagir comme sĂ©parĂ©es de lui par un nĂ©ant. On pourrait alors penser que certaines actions ont acquis un statut dâhabitude, que leur rĂ©itĂ©ration est facilitĂ©e par lâexpĂ©rience. Sartre ne pense pas lâhabitude en tant que telle. Avec lâexemple du joueur invĂ©tĂ©rĂ© qui essaie dâarrĂȘter de jouer, cet article tente dâune part de montrer une limite de la conceptualisation sartrienne. Dâautre part, en essayant de rĂ©inscrire cette analyse dans la perspective du projet originel, il sâagit de pointer vers la difficultĂ© pour un agent de changer de projet. Il apparaĂźt donc que lâexercice de la libertĂ© est vertigineux mais pas absolu
Nouveaux matériaux fluorescents pour diodes électroluminescentes organiques (OLEDs) émettant dans le proche infrarouge
Les diodes Ă©lectroluminescentes organiques (organic light-emitting diodes : OLEDs) sont des dispositifs Ă©lectroluminescents utilisant la fluorescence des molĂ©cules organiques comme mĂ©canisme dâĂ©mission de lumiĂšre. Bien que le phĂ©nomĂšne dâĂ©lectroluminescence organique soit connu depuis 1953, les dispositifs OLED nâont pas suscitĂ© un grand engouement au niveau de la recherche scientifique avant le dĂ©but des annĂ©es 1990. La faible viabilitĂ© de ces dispositifs, nĂ©cessitant alors une forte tension de fonctionnement pour de faibles performances, a grandement limitĂ© leur utilisation. Il faut attendre les travaux de Tang et Van Slyke en 1987 et le dĂ©veloppement des structures multicouches pour que la OLED puisse ĂȘtre perçue comme une vĂ©ritable alternative aux dispositifs inorganiques. Depuis, de nombreuses innovations ont permis dâobtenir des OLED efficaces dans le domaine du visible. Cependant, de nouvelles perspectives dâutilisation de la OLED dans le proche infrarouge (near infrared : NIR) comme la vision nocturne, les biosenseurs ou encore la photochimie, nĂ©cessitent le dĂ©veloppement Ă la fois dâĂ©metteurs performants dans le proche infrarouge et de nouvelles stratĂ©gies de conception. Les Ă©metteurs NIR sont gĂ©nĂ©ralement trĂšs peu efficaces puisque les mĂ©canismes de dĂ©sexcitation par relaxation vibrationnelle sont favorisĂ©s, ce qui les rend alors peu Ă©missifs. De plus, ils sont souvent trĂšs sensibles aux interactions intermolĂ©culaires, notamment Ă lâĂ©tat solide, ce qui limite leurs performances lorsquâils sont utilisĂ©s dans des OLEDs. Le dĂ©veloppement de OLEDs NIR prĂ©sente donc un vĂ©ritable challenge au vu de ces considĂ©rations.
Pour rĂ©pondre Ă cette demande, des molĂ©cules organiques prĂ©sentant une forte Ă©mission dans le NIR ont tout dâabord Ă©tĂ© synthĂ©tisĂ©es. DiffĂ©rentes stratĂ©gies de conception ont Ă©tĂ© mises en place afin de rĂ©duire les phĂ©nomĂšnes de relaxation vibrationnelle et dâagrĂ©gation dans ces molĂ©cules, tout en prĂ©sentant une forte Ă©mission dans le NIR. En utilisant conjointement un Ă©metteur dĂ©rivĂ© de cyanine pyrrolopyrrole complexĂ©e au difluorure de bore (BCPP-F2) avec un matĂ©riau prĂ©sentant un phĂ©nomĂšne de fluorescence retardĂ©e activĂ© thermiquement (thermally activated delayed fluorescence : TADF), une OLED montrant une efficacitĂ© quantique externe (EQE) de 5.3% Ă 790 nm a Ă©tĂ© fabriquĂ©e.----------Abstract Organic light-emitting diodes (OLEDs) are electroluminescent devices that use the fluorescence of organic molecules as a light-emitting mechanism. Although the phenomenon of organic electroluminescence has been known since 1953, OLED devices did not generate a great excitement in scientific research before the beginning of the 1990s. The poor performance of OLEDs, requiring high voltage and possessing low efficiencies, greatly limited their use. However, with the work of Tang and Van Slyke in 1987 and the development of multilayer structures, OLEDs started to be considered as a viable alternative to inorganic devices. Significant innovations have been made to obtain highly efficient OLED devices in the visible. Nevertheless, the use of OLEDs in the near infrared region (NIR) for applications such as night vision, biosensors or photochemistry, requires the development of NIR emitters and new architecture for OLEDs. NIR emitters are generally very inefficient due to non-radiative decay processes. Moreover, they are very sensitive to intermolecular interactions, particularly in the solid state, that limit their performance when used in OLEDs. Therefore, the development of NIR OLEDs remains an important challenge.
To meet this challenge, organic molecules, having a high emission in the NIR region, were synthesized. In order to obtain a strong NIR emission, different design strategies have been exploited to reduce the vibrational relaxation and aggregation. By using a BF2 pyrrolopyrrole cyanine complex (BCPP-F2) with a thermally activated delayed fluorescence (TADF) material, an OLED showing an external quantum efficiency (EQE) of 4.8% at 790 nm has been obtained.
Then, in order to shift the emission of the emitters towards higher wavelengths, the fluorine groups on the boron have been replaced by phenyl groups. The molecule (BCPP-Ph) showed an emission at 835 nm but exhibits a lower thermal stability. An OLED showing an EQE of 1% at wavelengths above 800 nm has been made.
Finally, curcuminoid derivatives were synthetized (CMB-F and CMB-Ph). These molecules have been targeted for their potential as TADF emitters and have shown a strong NIR emission. The effect of polarity and concentration on the emission of the emitters were studied, showing a strong positive solvatochromism consistent with charge-transfer states in TADF molecule
Comprendre Pourquoi JâAgis: Le Sens de lâAction en PremiĂšre Personne
In lieu of an abstract, here is a brief excerpt of the content:
"'De deux choses lâune : ou [la personne qui agit] est une personne, elle demeure la meÌme, et ses actes expliquent entieÌrement ce quâelle est ; ou ses actes peuvent toujours eÌtre interrogeÌs comme des eÌveÌnements du monde, et elle nâest jamais la meÌme quâelle-meÌme. Car inversement, lâacte est dâautant plus un vrai acte (et non un simple eÌveÌnement naturel du monde) quâil ne surgit pas de ce que sont les choses, mais change la face du monde. Il est lui-meÌme cette face changeÌe du monde' [Francis Wolff, Dire le monde].
Telle est lâantinomie de la relation de lâagent aÌ son action que deÌcrit Francis Wolff dans le troisieÌme chapitre de Dire le monde.Pour penser lâaction, il faut concevoir dans le meÌme mouvement un agent qui soit la cause de lâaction sans que cette action soit lâeffet de ce quâest lâagent. La solution que Francis Wolff fournit aÌ lâantinomie, dans le quatrieÌme chapitre de Dire le monde, repose sur le « je » et sur le concept de « jâagis ». Il ne sâagit pas ici dâen faire le commentaire, mais de trouver dans cette reÌsolution une source dâinspiration pour envisager la conscience de lâagent lorsquâil agit.
PrĂ©sentation : rationalitĂ© pratique et motivation morale dans lâĂ©thique des vertus et lâĂ©thique « existentielle »
Dans le prĂ©cĂ©dent numĂ©ro de Philonsorbonne, une premiĂšre partie du dossier « RationalitĂ© pratique et motivation morale » avait Ă©tĂ© publiĂ©e. Il sâagissait de rendre compte des travaux menĂ©s dans le cadre du projet unissant deux centres de recherches : le Centre de Philosophie Contemporaine de lâUniversitĂ© Paris 1 PanthĂ©on-Sorbonne et lâInstituto de Filosofia Pratica de lâUniversidade da Beira Interior au Portugal. Le projet intitulĂ© « RationalitĂ© pratique, jugement et motivation morale » a pu..
Severe episodes of extra cellular dehydration : an atypical adult presentation of cystic fibrosis
Cystic fibrosis (CF) is usually diagnosed during childhood by respiratory or gastro-intestinal symptoms. Hyponatremic hypochloremic dehydration with metabolic alkalosis is a rare but typical presentation of CF in infants. In contrast, only 3 cases have been described in adults. We report a case of CF in a 33-year-old Caucasian female presenting with a severe sodium and chloride depletion caused by inappropriate sweating. She experienced three episodes of severe dehydration before the diagnosis was suspected. Sweat chloride test was pathological and mild pulmonary involvement was found on CT scan. AF508 mutation and a rare mutation (3849+40 A/G) on the intron 19 of CFTR gene were found. Interestingly, our patient has a heterozygote twin sister, carrier of the same mutations of CFTR gene who also developed CF but with a different phenotype. We suspect modifier genes to be implicated in the differences observed between the two phenotypes. We discuss the physiopathology of electrolyte disturbance and review the other similar adults cases
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