Activity-Induced Remodeling of Olfactory Bulb Microcircuits Revealed by Monosynaptic Tracing

The continued addition of new neurons to mature olfactory circuits represents a remarkable mode of cellular and structural brain plasticity. However, the anatomical configuration of newly established circuits, the types and numbers of neurons that form new synaptic connections, and the effect of sensory experience on synaptic connectivity in the olfactory bulb remain poorly understood. Using in vivo electroporation and monosynaptic tracing, we show that postnatal-born granule cells form synaptic connections with centrifugal inputs and mitral/tufted cells in the mouse olfactory bulb. In addition, newly born granule cells receive extensive input from local inhibitory short axon cells, a poorly understood cell population. The connectivity of short axon cells shows clustered organization, and their synaptic input onto newborn granule cells dramatically and selectively expands with odor stimulation. Our findings suggest that sensory experience promotes the synaptic integration of new neurons into cell type-specific olfactory circuits

Lawson criterion for ignition exceeded in an inertial fusion experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion

A Constitutional Economics Perspective on Soft Paternalism

Using a framework that distinguishes short-term consumer preferences, individual reflective preferences and political preferences, we discuss from a constitutional economics perspective whether individuals find it in their common constitutional interest to endow representatives and bureaucrats with the competence to impose soft paternalist policies. The focus is specifically on soft paternalist policies, because these often work with non-transparent 'nudges' that are considered as manipulative in some contributions to the literature. We show that those soft paternalist policies that are manipulative indeed collide with three criteria of consumer sovereignty, reflective sovereignty and citizen sovereignty that can be argued to represent common constitutional interest of citizens. On the other hand, we argue that the set of paternalist policies that is deemed acceptable on the constitutional level is restricted to non-manipulative instruments, and their application as government policies is limited to cases with stable and very homogenous preferences. However, we also argue that competitive markets are capable of supplying many mechanisms that allow individuals to cope with problems in their decision-making processes on a private level.In diesem Papier wird untersucht, ob und in welchem Umfang paternalistische politische Maßnahmen gerechtfertigt werden können, sofern diese nicht mit klaren Regeln arbeiten, sondern Schwachpunkte individueller Entscheidungsprozesse nutzen, wie sie aus der Verhaltensökonomik bekannt sind. Die zur Beurteilung herangezogenen Kriterien sind aus der verfassungsökonomischen Theorie abgeleitet. Im Ergebnis zeigt sich, dass der sogenannte 'weiche' Paternalismus nur in sehr seltenen Fällen verallgemeinerbaren Interessen der Bürger entspricht, nämlich dann, wenn seine Instrumente vollständig transparent und nicht manipulativ sind, sowie die Entscheidungsautonomie des Einzelnen gewahrt bleibt

Flexible Conversion Ratio Fast Reactor Systems Evaluation Final Report

Project DE-FC07-06ID14733Executive Summary: The goal of this project is to develop the conceptual designs of fast flexible conversion ratio reactors using lead and liquid salt coolants and to compare the results with a gascooled fast reactor developed in an MIT NERI project and a sodium-cooled reactor under development at ANL. To maintain the scope of the study manageable within the 2-year time frame and funding constraints, core designs that fit in the same reactor plant were executed for two limiting conversion ratios: (1) near zero, to transmute legacy waste and (2) near unity, to operate in a sustainable closed cycle. To reap the benefits of economy of scale, a large power rating of 2400MWt was set as the target thermal power for both reactor designs. In addition, the achievement of inherent reactor shutdown in unprotected accidents (without scram) was set as a desirable goal.United States. Dept. of Energy (Award DE-FC07-06ID14733

Thioredoxin is required for S-nitrosation of procaspase-3 and the inhibition of apoptosis in Jurkat cells

S-nitrosation is a posttranslational, oxidative addition of NO to cysteine residues of proteins that has been proposed as a cGMP-independent signaling pathway [Hess DT, Matsumoto A, Kim SO, Marshall HE, Stamler JS (2005) Nat Rev Mol Cell Biol 6:150–166]. A paradox of S-nitrosation is that only a small set of reactive cysteines are modified in vivo despite the promiscuous reactivity NO exhibits with thiols, precluding the reaction of free NO as the primary mechanism of S-nitrosation. Here we show that a specific transnitrosation reaction between procaspase-3 and thioredoxin-1 (Trx) occurs in cultured human T cells and prevents apoptosis. Trx participation in catalyzing transnitrosation reactions in cells may be general because this protein has numerous protein–protein interactions and plays a key role in cellular redox homeostasis [Powis G, Montfort WR (2001) Annu Rev Pharmacol Toxicol 41:261–295], nitrosothiol content in cells [Haendeler J, Hoffmann J, Tischler V, Berk BC, Zeiher AM, Dimmeler S (2002) Nat Cell Biol 4:743–749], and antiapoptotic signaling