The Unity of the Virtues in a Missionary Key

The thesis of the unity of the virtues—one must possess all of the virtues to possess even one of them—was upheld in different forms by Plato, Aristotle, Augustine, and Aquinas. However, contemporary moralists almost universally decry this thesis as distorting the nature of virtue as it is materialized in the lives and actions of ordinary people. Unfortunately, academic discourse regarding the unity of the virtues has tended to be either entirely theoretical or narrowly limited to particular individuals or groups as “test cases” regarding the validity of the thesis. It is both significant and reinvigorating, therefore, that in his apostolic exhortation, , Pope Francis evokes the thesis of the unity Evangelii gaudium of the virtues as pivotal to the task of evangelization. The purpose of the current essay is to reevaluate the merit and practical applicability of the unity of the virtues in light of the “missionary option” as proposed by Pope Francis

Subtype-specific plasticity of inhibitory circuits in motor cortex during motor learning.

Motor skill learning induces long-lasting reorganization of dendritic spines, principal sites of excitatory synapses, in the motor cortex. However, mechanisms that regulate these excitatory synaptic changes remain poorly understood. Here, using in vivo two-photon imaging in awake mice, we found that learning-induced spine reorganization of layer (L) 2/3 excitatory neurons occurs in the distal branches of their apical dendrites in L1 but not in the perisomatic dendrites. This compartment-specific spine reorganization coincided with subtype-specific plasticity of local inhibitory circuits. Somatostatin-expressing inhibitory neurons (SOM-INs), which mainly inhibit distal dendrites of excitatory neurons, showed a decrease in axonal boutons immediately after the training began, whereas parvalbumin-expressing inhibitory neurons (PV-INs), which mainly inhibit perisomatic regions of excitatory neurons, exhibited a gradual increase in axonal boutons during training. Optogenetic enhancement and suppression of SOM-IN activity during training destabilized and hyperstabilized spines, respectively, and both manipulations impaired the learning of stereotyped movements. Our results identify SOM inhibition of distal dendrites as a key regulator of learning-related changes in excitatory synapses and the acquisition of motor skills

Resonance enhanced turbulent transport

The effect of oscillatory shear flows on turbulent transport of passive scalar fields is studied by numerical computations based on the results provided by E. Kim [Physics of Plasmas 13, 022308 (2006)] . Turbulent diffusion is found to depend crucially on the competition between suppression due to shearing and enhancement due to resonances, depending on the characteristic time and length scales of shear flow and turbulence. Enhancements in transport occur for turbulence with finite memory time either due to Doppler or parametric resonances. Scalings of turbulence amplitude and transport are provided in different parameter spaces. The results suggest that oscillatory shear flows are not only less efficient in regulating turbulence, but also can enhance the value of turbulent diffusion, accelerating turbulent transport

Happy lottery winners and lottery-ticket bias

Ministry of Education, Singapore under its Academic Research Funding Tier