17 research outputs found
The Use of Models to Predict the Presence and Aggressiveness of Prostate Cancer on Prostate Biopsy
Contagion émotionnelle chez l'humain : étude de la transmission des émotions positives via les odeurs endogÚnes et exogÚnes véhiculées par le corps
Chez lâĂȘtre humain lâodeur du corps dâun individu semble ĂȘtre porteuse dâinformations de nature trĂšs variĂ©e Ă son sujet, et ces molĂ©cules une fois captĂ©es par dâautres individus semblent causer des effets Ă la fois cognitifs et physiologiques chez ces derniers. La littĂ©rature montre que les individus sont capables de collecter des informations sur des traits constants ainsi que sur des Ă©tats transitoires dâune personne, en Ă©tant exposĂ©s Ă son odeur uniquement, et ceci de maniĂšre non consciente. Parmi les Ă©tats internes transitoires Ă©tant communiquĂ©s via le sens olfactif, un facteur a rĂ©cemment Ă©tĂ© lâobjet dâĂ©tudes prometteuses : les odeurs corporelles semblent Ă©galement ĂȘtre porteuses d'informations sur les Ă©motions ressenties par la personne qui les Ă©met. Ces Ă©tudes se sont concentrĂ©es sur le cas des Ă©motions nĂ©gatives, mettant de cĂŽtĂ© les Ă©tats positifs pourtant porteurs de bĂ©nĂ©fices majeurs pour les individus, les groupes, et la sociĂ©tĂ©. Outre ces lacunes, une autre zone dâombre prend forme lorsque lâon sâintĂ©resse Ă un facteur allant souvent de pair avec nos odeurs corporelles naturelles : les odeurs exogĂšnes. LâĂȘtre humain se parfume depuis lâantiquitĂ© et ces odeurs rajoutĂ©es par-dessus notre odeur endogĂšne peuvent, logiquement, interagir avec celle-ci. Le but de cette thĂšse a Ă©tĂ© de tenter dâĂ©claircir ces zones dâombres multiples pour comprendre si une transmission des Ă©tats Ă©motionnels positifs via le sens olfactif existait chez lâhumain, et quelle potentielle modulation le parfum pouvait avoir sur celle-ci. Pour cela, nous avons mis en place dans une premiĂšre Ă©tude un paradigme expĂ©rimental chez des « donneurs », de qui nous avons collectĂ© les odeurs corporelles pendant quâils ressentaient des Ă©motions positives ou non, puis les avons fait sentir dans un deuxiĂšme temps Ă des « receveurs », chez qui nous avons effectuĂ© des mesures physiologiques, verbales, et comportementales. Nos rĂ©sultats montrent que cette transmission semble ĂȘtre possible et quâil sâagirait mĂȘme non seulement dâune transmission mais dâune « contagion », des indices de lâaffect positif des donneurs Ă©tant retrouvĂ©s chez les receveurs aprĂšs exposition aux odeurs des premiers. Dans une deuxiĂšme Ă©tude, nous avons testĂ© cette fois-ci une mĂ©thode potentiellement plus efficace et Ă©cologique dâinduire des Ă©motions : via rĂ©alitĂ© virtuelle. Les rĂ©sultats de lâĂ©tude 1 nâont pas Ă©tĂ© rĂ©pliquĂ©s, ce qui nous a fait prendre conscience de la nature subtile et hautement dĂ©pendante du contexte de ces signaux chimiques. Nous avons alors dĂ©cidĂ© dâaugmenter encore le niveau de « rĂ©alisme » en menant une troisiĂšme Ă©tude faite Ă domicile. Dans cette Ă©tude les donneurs et receveurs vivaient sous le mĂȘme toit en tant que colocataires ou couples, ce qui nous a permis dâexplorer lâimpact de la nature de la relation liant les deux partenaires communicants, ainsi que des niveaux de sociabilitĂ© de ceux-ci. La derniĂšre Ă©tude est une preuve de concept et rend compte du dĂ©veloppement mĂ©thodologique dâun outil pour mieux Ă©tudier les bases chimiques liĂ©es Ă ce type de communication, via la captation par des polymĂšres des molĂ©cules odorantes au niveau du cou et des aisselles de participants, par la suite analysĂ©s en GC-MS. Dans les trois premiĂšres Ă©tudes le faisceau dâĂ©vidences pointe vers un effet non perturbateur du parfum sur la communication chimique des Ă©motions positives, avec mĂȘme pour certaines mesures verbales un potentiel synergique du parfum et de lâodeur corporelle positive qui mettrait en avant des caractĂ©ristiques de cette derniĂšre. Finalement, un papier hybride mĂȘlant opinion, revue de la littĂ©rature et prĂ©sentant Ă©galement quelques donnĂ©es expĂ©rimentales, sâintĂ©resse aux multiples dĂ©fis et obstacles que doit surmonter le domaine de la communication chimique chez lâhumain, dont tous ont Ă©tĂ© rencontrĂ©s au cours de cette thĂšse, et certaines pistes de rĂ©flexion ainsi que des perspectives sont abordĂ©es.In humans, the smell of an individual's body seems to carry a wide variety of information about them, and these molecules once caught by other individuals, whether relatives or strangers, seem to cause both cognitive and physiological effects in them. The scientific literature shows that individuals are able to gather information about another person's persistent traits as well as transient states by being exposed to their scent alone, and this in a non-conscious way. Among the transient internal states that can be communicated via the olfactory sense, one factor has recently been the subject of promising studies: body odors also seem to carry information about the emotions felt by the person emitting them. Inappropriately, these studies have been focused on negative emotions, leaving aside positive states, despite the fact that they carry major benefits for individuals, groups, as well as for society at large. In addition to these shortcomings, another literature gap is found when one looks at a factor that often goes hand in hand with our natural body odors: exogenous odors. Humans have been perfuming themselves directly (on the skin) and indirectly (via clothing or ambient scents) since antiquity and these odors added on top of our endogenous odor can, logically, interact with it. The aim of this thesis was to try to clarify these multiple gaps in the literature, in order to understand if a transmission of positive emotional states via the olfactory sense existed in humans, and what potential modulation perfume could have on it. To this end, in a first study, we set up an experimental paradigm with "donors", from whom we collected body odors while they were feeling positive emotions or not, and then in a second step we exposed âreceiversâ to these odors, in whom we carried out physiological, verbal, and behavioral measurements. Our results show that this transmission of positive states seems possible in humans and that it is not only a transmission but rather a "contagion", because indices of the positive affect of the donors are found in the receivers when the latter are exposed to the odors of the former. In a second study, we repeated the same experimental design, this time testing a potentially more effective and ecologically valid method to induce emotions: via virtual reality. The results of the first study were not replicated, which made us even more aware of the subtle and highly context-dependent nature of these chemical signals. To better understand this, we decided to further increase the level of "realism" by conducting a third study which participants did at-home. In this study the donors and receivers both lived under the same roof, as either roommates or couples, which allowed us to better understand the impact of the nature of the relationship between the two communicating partners, as well as of their level of sociability. The last study is a proof of concept and reports on the methodological development of a device to better study the chemical bases underlying this type of communication, via the polymer capture of odorant molecules on the necks and armpits of participants, subsequently analyzed in GC-MS. In the first three studies, the sum of results points to a non-disruptive effect of perfume on the chemical communication of positive emotions, with even for some verbal measures, a synergistic potential of perfume and positive body odor that would highlight characteristics of the latter. Finally, a hybrid paper mixing opinion, literature review, and also presenting some experimental data, focuses on the multiple challenges and obstacles that the field of chemical communication in humans has to overcome, all of which have been encountered during this thesis, as well as gives some insights and perspectives for the future
MallarmeÌ's children: symbolism and the renewal of experience
In a narrative gracefully combining intellectual and cultural history, Richard Cåndida Smith unfolds the legacy of Stéphane Mallarmé (1842-1898), the poet who fathered the symbolist movement in poetry and art. The symbolists found themselves in the midst of the transition to a world in which new media devoured cultural products and delivered them to an ever-growing public. Their goal was to create and oversee a new elite culture, one that elevated poetry by removing it from a direct relationship to experience. Instead, symbolist poetry was dedicated to exploring discourse itself, and its practitioners to understanding how language shapes consciousness.Cåndida Smith investigates the intellectual context in which symbolists came to view artistic practice as a form of knowledge. He relates their work to psychology, especially the ideas of William James, and to language and the emergence of semantics. Through the lens of symbolism, he focuses on a variety of subjects: sexual liberation and the erotic, anarchism, utopianism, labor, and women's creative role. Paradoxically, the symbolists' reconfiguration of elite culture fit effectively into the modern commercial media. After Mallarmé was rescued from obscurity, symbolism became a valuable commodity, exported by France to America and elsewhere in the market-driven turn-of-the-century world. Mallarmé's Children traces not only how poets regarded their poetry and artists their art but also how the public learned to think in new ways about cultural work and to behave differently as a result
Asymmetric Mannich Synthesis of 뱉Amino Esters by Anion-Binding Catalysis
We
report a scalable, one-pot Mannich route to enantioenriched
α-amino esters by direct reaction of α-chloroglycine ester
as a practical imino ester surrogate. The reaction is promoted by
a chiral aminothiourea, which is proposed to operate cooperatively
by generating an iminium ion by chloride abstraction and an enolate
by deprotonation, followed by highly stereoselective CâC bond
formation between both reactive intermediates associated non-covalently
within the catalyst framework
Molecular and physiological logics of the pyruvate-induced response of a novel transporter in Bacillus subtilis
At the heart of central carbon metabolism, pyruvate is a pivotal metabolite in all living cells. Bacillus subtilis is able to excrete pyruvate as well as to use it as the sole carbon source. We herein reveal that ysbAB (renamed pftAB), the only operon specifically induced in pyruvate-grown B. subtilis cells, encodes a heterooligomeric membrane complex which operates as a facilitated transport system specific for pyruvate, thereby defining a novel class of transporter. We demonstrate that the LytST two-component system is responsible for the induction of pftAB in the presence of pyruvate by binding of the LytT response regulator to a palindromic region upstream of pftAB. We show that both glucose and malate, the preferred carbon sources for B. subtilis, trigger the binding of CcpA upstream of pftAB, which results in its catabolite repression. However, an additional CcpA-independent mechanism represses pftAB in the presence of malate. Screening a genome-wide transposon mutant library, we find that an active malic enzyme replenishing the pyruvate pool is required for this repression. We next reveal that the higher the influx of pyruvate, the stronger the CcpA-independent repression of pftAB, which suggests that intracellular pyruvate retroinhibits pftAB induction via LytST. Such a retroinhibition challenges the rational design of novel nature-inspired sensors and synthetic switches but undoubtedly offers new possibilities for the development of integrated sensor/controller circuitry. Overall, we provide evidence for a complete system of sensors, feed-forward and feedback controllers that play a major role in environmental growth of B. subtilis. [br/]
IMPORTANCE Pyruvate is a small-molecule metabolite ubiquitous in living cells. Several species also use it as a carbon source as well as excrete it into the environment. The bacterial systems for pyruvate import/export have yet to be discovered. Here, we identified in the model bacterium Bacillus subtilis the first import/export system specific for pyruvate, PftAB, which defines a novel class of transporter. In this bacterium, extracellular pyruvate acts as the signal molecule for the LytST two-component system (TCS), which in turn induces expression of PftAB. However, when the pyruvate influx is high, LytST activity is drastically retroinhibited. Such a retroinhibition challenges the rational design of novel nature-inspired sensors and synthetic switches but undoubtedly offers new possibilities for the development of integrated sensor/controller circuitry
Crystal Growth and First Crystallographic Characterization of Mixed Uranium(IV)âPlutonium(III) Oxalates
The mixed-actinide uraniumÂ(IV)âplutoniumÂ(III)
oxalate single crystals (NH<sub>4</sub>)<sub>0.5</sub>[Pu<sup>III</sup><sub>0.5</sub>U<sup>IV</sup><sub>0.5</sub>(C<sub>2</sub>O<sub>4</sub>)<sub>2</sub>·H<sub>2</sub>O]·<i>n</i>H<sub>2</sub>O (<b>1</b>) and (NH<sub>4</sub>)<sub>2.7</sub>Pu<sup>III</sup><sub>0.7</sub>U<sup>IV</sup><sub>1.3</sub>(C<sub>2</sub>O<sub>4</sub>)<sub>5</sub>·<i>n</i>H<sub>2</sub>O (<b>2</b>) have been prepared by the diffusion of different ions through membranes
separating compartments of a triple cell. UVâvis, Raman, and
thermal ionization mass spectrometry analyses demonstrate the presence
of both uranium and plutonium metal cations with conservation of the
initial oxidation state, U<sup>IV</sup> and Pu<sup>III</sup>, and
the formation of mixed-valence, mixed-actinide oxalate compounds.
The structure of <b>1</b> and an average structure of <b>2</b> were determined by single-crystal X-ray diffraction and
were solved by direct methods and Fourier difference techniques. Compounds <b>1</b> and <b>2</b> are the first mixed uraniumÂ(IV)âplutoniumÂ(III)
compounds to be structurally characterized by single-crystal X-ray
diffraction. The structure of <b>1</b>, space group <i>P</i>4/<i>n</i>, <i>a</i> = 8.8558(3) Ă
, <i>b</i> = 7.8963(2) Ă
, <i>Z</i> = 2, consists of
layers formed by four-membered rings of the two actinide metals occupying
the same crystallographic site connected through oxalate ions. The
actinide atoms are nine-coordinated by oxygen atoms from four bidentate
oxalate ligands and one water molecule, which alternates up and down
the layer. The single-charged cations and nonbonded water molecules
are disordered in the same crystallographic site. For compound <b>2</b>, an average structure has been determined in space group <i>P</i>6/<i>mmm</i> with <i>a</i> = 11.158(2)
Ă
and <i>c</i> = 6.400(1) Ă
. The honeycomb-like
framework [Pu<sup>III</sup><sub>0.7</sub>U<sup>IV</sup><sub>1.3</sub>(C<sub>2</sub>O<sub>4</sub>)<sub>5</sub>]<sup>2.7â</sup> results
from a three-dimensional arrangement of mixed (U<sub>0.65</sub>Pu<sub>0.35</sub>)ÂO<sub>10</sub> polyhedra connected by five bis-bidentate
Ό<sup>2</sup>-oxalate ions in a trigonal-bipyramidal configuration
Crystal Growth and First Crystallographic Characterization of Mixed Uranium(IV)âPlutonium(III) Oxalates
The mixed-actinide uraniumÂ(IV)âplutoniumÂ(III)
oxalate single crystals (NH<sub>4</sub>)<sub>0.5</sub>[Pu<sup>III</sup><sub>0.5</sub>U<sup>IV</sup><sub>0.5</sub>(C<sub>2</sub>O<sub>4</sub>)<sub>2</sub>·H<sub>2</sub>O]·<i>n</i>H<sub>2</sub>O (<b>1</b>) and (NH<sub>4</sub>)<sub>2.7</sub>Pu<sup>III</sup><sub>0.7</sub>U<sup>IV</sup><sub>1.3</sub>(C<sub>2</sub>O<sub>4</sub>)<sub>5</sub>·<i>n</i>H<sub>2</sub>O (<b>2</b>) have been prepared by the diffusion of different ions through membranes
separating compartments of a triple cell. UVâvis, Raman, and
thermal ionization mass spectrometry analyses demonstrate the presence
of both uranium and plutonium metal cations with conservation of the
initial oxidation state, U<sup>IV</sup> and Pu<sup>III</sup>, and
the formation of mixed-valence, mixed-actinide oxalate compounds.
The structure of <b>1</b> and an average structure of <b>2</b> were determined by single-crystal X-ray diffraction and
were solved by direct methods and Fourier difference techniques. Compounds <b>1</b> and <b>2</b> are the first mixed uraniumÂ(IV)âplutoniumÂ(III)
compounds to be structurally characterized by single-crystal X-ray
diffraction. The structure of <b>1</b>, space group <i>P</i>4/<i>n</i>, <i>a</i> = 8.8558(3) Ă
, <i>b</i> = 7.8963(2) Ă
, <i>Z</i> = 2, consists of
layers formed by four-membered rings of the two actinide metals occupying
the same crystallographic site connected through oxalate ions. The
actinide atoms are nine-coordinated by oxygen atoms from four bidentate
oxalate ligands and one water molecule, which alternates up and down
the layer. The single-charged cations and nonbonded water molecules
are disordered in the same crystallographic site. For compound <b>2</b>, an average structure has been determined in space group <i>P</i>6/<i>mmm</i> with <i>a</i> = 11.158(2)
Ă
and <i>c</i> = 6.400(1) Ă
. The honeycomb-like
framework [Pu<sup>III</sup><sub>0.7</sub>U<sup>IV</sup><sub>1.3</sub>(C<sub>2</sub>O<sub>4</sub>)<sub>5</sub>]<sup>2.7â</sup> results
from a three-dimensional arrangement of mixed (U<sub>0.65</sub>Pu<sub>0.35</sub>)ÂO<sub>10</sub> polyhedra connected by five bis-bidentate
Ό<sup>2</sup>-oxalate ions in a trigonal-bipyramidal configuration
Crystal Growth and First Crystallographic Characterization of Mixed Uranium(IV)âPlutonium(III) Oxalates
The mixed-actinide uraniumÂ(IV)âplutoniumÂ(III)
oxalate single crystals (NH<sub>4</sub>)<sub>0.5</sub>[Pu<sup>III</sup><sub>0.5</sub>U<sup>IV</sup><sub>0.5</sub>(C<sub>2</sub>O<sub>4</sub>)<sub>2</sub>·H<sub>2</sub>O]·<i>n</i>H<sub>2</sub>O (<b>1</b>) and (NH<sub>4</sub>)<sub>2.7</sub>Pu<sup>III</sup><sub>0.7</sub>U<sup>IV</sup><sub>1.3</sub>(C<sub>2</sub>O<sub>4</sub>)<sub>5</sub>·<i>n</i>H<sub>2</sub>O (<b>2</b>) have been prepared by the diffusion of different ions through membranes
separating compartments of a triple cell. UVâvis, Raman, and
thermal ionization mass spectrometry analyses demonstrate the presence
of both uranium and plutonium metal cations with conservation of the
initial oxidation state, U<sup>IV</sup> and Pu<sup>III</sup>, and
the formation of mixed-valence, mixed-actinide oxalate compounds.
The structure of <b>1</b> and an average structure of <b>2</b> were determined by single-crystal X-ray diffraction and
were solved by direct methods and Fourier difference techniques. Compounds <b>1</b> and <b>2</b> are the first mixed uraniumÂ(IV)âplutoniumÂ(III)
compounds to be structurally characterized by single-crystal X-ray
diffraction. The structure of <b>1</b>, space group <i>P</i>4/<i>n</i>, <i>a</i> = 8.8558(3) Ă
, <i>b</i> = 7.8963(2) Ă
, <i>Z</i> = 2, consists of
layers formed by four-membered rings of the two actinide metals occupying
the same crystallographic site connected through oxalate ions. The
actinide atoms are nine-coordinated by oxygen atoms from four bidentate
oxalate ligands and one water molecule, which alternates up and down
the layer. The single-charged cations and nonbonded water molecules
are disordered in the same crystallographic site. For compound <b>2</b>, an average structure has been determined in space group <i>P</i>6/<i>mmm</i> with <i>a</i> = 11.158(2)
Ă
and <i>c</i> = 6.400(1) Ă
. The honeycomb-like
framework [Pu<sup>III</sup><sub>0.7</sub>U<sup>IV</sup><sub>1.3</sub>(C<sub>2</sub>O<sub>4</sub>)<sub>5</sub>]<sup>2.7â</sup> results
from a three-dimensional arrangement of mixed (U<sub>0.65</sub>Pu<sub>0.35</sub>)ÂO<sub>10</sub> polyhedra connected by five bis-bidentate
Ό<sup>2</sup>-oxalate ions in a trigonal-bipyramidal configuration
Local Structure, Dynamics, and the Mechanisms of Oxide Ionic Conduction in Bi<sub>26</sub>Mo<sub>10</sub>O<sub>69</sub>
We
report the results of a computational and experimental study
into the stabilized fluorite-type ÎŽ-Bi<sub>2</sub>O<sub>3</sub>-related phase Bi<sub>26</sub>Mo<sub>10</sub>O<sub>69</sub> aimed
at clarifying the local and average structure, for which two distinct
models have previously been proposed, and the oxide ionic diffusion
mechanism, for which three distinct models have previously been proposed.
Concerning the structure, we propose a new model in which some molybdenum
atoms have higher coordination numbers than 4; that is, some MoO<sub>5</sub> trigonal bipyramids coexist with MoO<sub>4</sub> tetrahedra.
This accounts for the additional oxygen required to achieve the nominal
composition (a tetrahedron-only model gives Bi<sub>26</sub>Mo<sub>10</sub>O<sub>68</sub>) without invoking a previously proposed unbonded
interstitial site, which we found to be energetically unfavorable.
All these MoO<sub><i>x</i></sub> units are rotationally
disordered above a first-order transition at 310 °C, corresponding
to a first-order increase in conductivity. Concerning oxide ionic
diffusion above that transition temperature, we found excellent agreement
between the results of ab initio molecular dynamics simulations and
quasielastic neutron scattering experiments. Our results indicate
a mechanism related to that proposed by Holmes et al. (<i>Chem.
Mater.</i> <b>2008</b>, <i>20</i>, 3638), with
the role previously assigned to partially occupied interstitial oxygen
sites played instead by transient but stable MoO<sub>5</sub> trigonal
bipyramids and with more relaxed requirements in terms of the orientation
and timing of the diffusive jumps