A stereoselective method for the synthesis of axially chiral biaryl scaffolds by CH bond functionalization was accomplished using chiral sulfoxide both as the directing group enabling the ...regioselective activation of a CH bond and as the chiral auxiliary generating an asymmetric environment in the coordination sphere of the metal complex. We have demonstrated the directing ability of the p‐tolylsulfinyl group in promoting the Pd(II)‐catalyzed CH olefination of biphenyls.
The functionalization of 3-(difluoromethyl)pyridine has been developed via direct deprotonation of -CHF2 with a lithiated base and subsequent trapping with various electrophiles in THF. In situ ...quenching gives access to 3-pyridyl-CF2-SiMe2Ph as a new silylated compound, which can be postfunctionalized with a fluoride source to obtain a larger library of 3-(difluoroalkyl)pyridines that could not be accessed via direct deprotonation.
Research on radiation tolerant electronics has increased rapidly over the last few years, resulting in many interesting approaches to model radiation effects and design radiation hardened integrated ...circuits and embedded systems. This research is strongly driven by the growing need for radiation hardened electronics for space applications, high-energy physics experiments such as those on the large hadron collider at CERN, and many terrestrial nuclear applications, including nuclear energy and safety management. With the progressive scaling of integrated circuit technologies and the growing complexity of electronic systems, their ionizing radiation susceptibility has raised many exciting challenges, which are expected to drive research in the coming decade.After the success of the first Special Issue on Radiation Tolerant Electronics, the current Special Issue features thirteen articles highlighting recent breakthroughs in radiation tolerant integrated circuit design, fault tolerance in FPGAs, radiation effects in semiconductor materials and advanced IC technologies and modelling of radiation effects.
Social Security and Family Support Leroux, M.-L.; Pestieau, P.
The Canadian journal of economics,
February/février 2014, Letnik:
47, Številka:
1
Journal Article, Web Resource
Recenzirano
Odprti dostop
This paper shows how the role of the market, the state and the family in providing old-age support has evolved over time with changes in factors such as the reliability and the effectiveness of ...family support, the interest rate, the cost of public funds, and earning inequality. Agents with different productivity vote over the size of a Beveridgian pension system. When children assistance is certain, agents may rely exclusively on family and prefer no pension. However, when the size and the probability of family generosity decrease, social security is more likely to emerge. Cet article montre comment le rôle du marché, de l'état et de la famille dans l'aide aux personnes âgées a changé au cours du temps avec l'évolution de facteurs tels que la fiabilité et l'efficience de l'aide familiale, le taux d'intérêt, le coût des fonds publics, et les inégalités de revenus. Les agents qui ont des salaires différents votent sur la taille d'un régime de retraite à la Beveridge. Quand l'aide des enfants est assurée, les agents peuvent s'en remettre exclusivement à la famille et préférer ne pas avoir de régime de retraites. Cependant, quand la taille et la probabilité de l'aide familiale décroissent, un régime de retraites est davantage susceptible d'émerger.
Relying on a populace well-educated in family history based in ancestral genealogy, a robust national genomics sector has developed in Québec over the past decade-and-a-half. The same period roughly ...coincides with a fourfold increase in the number of individuals and organizations in the region self-identifying with a mixed-race form of indigeneity that is counter to existing Indigenous understandings of kinship and citizenship. This paper examines how recent efforts by genetic scientists, working on a multi-year research project on the ‘diversity’of the Québec gene pool, intervene in complex settler-Indigenous relations by redefining indigeneity according to the logics of ‘Native American DNA’. Specifically, I demonstrate how genetic scientists mobilize genes associated with Indigenous peoples in ways that support regional efforts to govern settler-Indigenous relations in favour of otherwise white settler claims to Indigenous lands.
We study the demand for Long Term Care (LTC hereafter) insurance in a setting where agents have state‐dependent preferences over both a daily life consumption good and LTC expenditures. We assume ...that dependency creates a demand for LTC expenditures while decreasing the marginal utility of daily life consumption, for any given consumption level. Agents optimize over their consumption of both goods as well as over the amount of LTC insurance (LTCI). We first show that some agents optimally choose not to insure themselves, while no agent wishes to buy complete insurance, in accordance with the so‐called LTCI puzzle. At equilibrium, the transfer received from the insurer covers only a fraction of the LTC expenditures. The demand for LTCI need not increase with income when preferences are non state‐dependent or insurance is actuarially unfair. Also, preferences have to be state‐dependent with no insurance bought to rationalize the empirical observation of a higher marginal utility at equilibrium when autonomous. Finally, focusing on iso‐elastic preferences, we recover the empirical observation that health/LTC expenditures are not very sensitive to income, and we show that LTCI as a fraction of income should decrease with income and then become nil above a threshold.
The palladium‐catalyzed silylcyanation of ynamides is described. This reaction is fully regioselective, delivering tetrasubstituted 2‐aminoacrylonitriles derivatives exclusively. Unexpectedly, the ...nature (aryl or alkyl) of the substituent located at the β‐position of the ynamide directly controls the stereoselectivity. The reaction tolerates a number of functional groups and can be considered as the first general access to fully substituted 2‐aminoacrylonitriles. Given the singular reactivity observed, a computational study was performed to shed light on the mechanism of this intriguing transformation. Relying on the specific reactivity of the newly installed vinylsilane functionality, the scope of 2‐aminoacrylonitriles has been enlarged by postfunctionalization.
Tetrasubstituted 2‐aminoacrylonitriles (α‐enaminonitriles) are underinvestigated building blocks due to the lack of methodologies to synthesize them in a controlled manner. A general access to these valuable scaffolds accompanied by mechanistic investigations and DFT calculations is described. This highly regio‐ and stereoselective strategy relies on the use of the first intermolecular silylcyanation of ynamides.
Soon after the discovery of polymeric vesicles (polymersomes), reports of their high membrane stability raised hopes for the development of next generation vesicles for drug delivery and diagnostic ...applications. Twenty-five years later, however, liposomes remain the only clinically tested colloidal vesicular formulations. To highlight the translational challenges faced by polymersomes, we critically reviewed a selection of polymersome formulations with a focus on their pharmacokinetic and pharmacodynamic aspects.
In this minireview, we discuss the progress of polymersome formulations towards clinical translation and highlight key opportunities and challenges.
Most motile and all non-motile (also known as primary) eukaryotic cilia possess microtubule-based axonemes that are assembled at the cell surface to form hair-like or more elaborate compartments ...endowed with motility and/or signaling functions. Such compartmentalized ciliogenesis depends on the core intraflagellar transport (IFT) machinery and the associated Bardet-Biedl syndrome complex (BBSome) for dynamic delivery of ciliary components. The transition zone (TZ), an ultrastructurally complex barrier or ‘gate’ at the base of cilia, also contributes to the formation of compartmentalized cilia. Yet, some ciliated protists do not have IFT components and, like some metazoan spermatozoa, use IFT-independent mechanisms to build axonemes exposed to the cytosol. Moreover, various ciliated protists lack TZ components, whereas Drosophila sperm surprisingly requires the activity of dynamically localized TZ proteins for cytosolic ciliogenesis. Here, we discuss the various ways eukaryotes use IFT and/or TZ proteins to generate the wide assortment of compartmentalized and cytosolic cilia observed in nature. Consideration of the different ciliogenesis pathways allows us to propose how three types of cytosol-exposed cilia (primary, secondary and tertiary), including cilia found in the human sperm proximal segment, are likely generated by evolutionary derivations of compartmentalized ciliogenesis.
In this minireview, Leroux and Avidor-Reiss discuss the various ways eukaryotes use intraflagellar transport and/or transition zone proteins to generate a wide assortment of compartmentalized and cytosolic cilia.
Organogels are semi-solid systems, in which an organic liquid phase is immobilized by a three-dimensional network composed of self-assembled, intertwined gelator fibers. Despite their majoritarily ...liquid composition, these systems demonstrate the appearance and rheological behaviour of solids. Investigative research pertaining to these systems has only picked up speed in the last few decades. Consequently, many burning questions regarding organogel systems, such as the specific molecular requirements guaranteeing gelation, still await definite answers. Nonetheless, the application of different organogel systems to various areas of interest has been quick to follow their discoveries. Unfortunately, their use in drug delivery is still quite limited by the scarce toxicology information available on organogelators, as well as by the few pharmaceutically-accepted solvents used in gel systems. This review aims at providing a global view of organogels, with special emphasis on the interplay between the gelator's structural characteristics and the ensuing intermolecular interactions. A subsequent focus is placed on the application of organogels as drug delivery platforms for active agent administration
via diverse routes such as transdermal, oral, and parenteral.
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