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We show conditional lower bounds for well-studied #P-hard problems: The number of satisfying assignments of a 2-CNF formula with n variables cannot be computed in time exp( o ( n )), and the same is true for computing the number of all independent sets in an n -vertex graph. The permanent of an n × n matrix with entries 0 and 1 cannot be computed in time exp( o ( n )). The Tutte polynomial of an n -vertex multigraph cannot be computed in time exp( o ( n )) at most evaluation points ( x , y ) in the case of multigraphs, and it cannot be computed in time exp( o ( n /poly log n )) in the case of simple graphs. Our lower bounds are relative to (variants of) the Exponential Time Hypothesis (ETH), which says that the satisfiability of n -variable 3-CNF formulas cannot be decided in time exp( o ( n )). We relax this hypothesis by introducing its counting version #ETH; namely, that the satisfying assignments cannot be counted in time exp( o ( n )). In order to use #ETH for our lower bounds, we transfer the sparsification lemma for d -CNF formulas to the counting setting.

Excited states in the $T_z=-1$ nucleus $^{70}$Kr have been populated using inelastic scattering of a radioactive $^{70}$Kr beam as well as one- and two-neutron removal reactions from $^{71,72}$Kr at intermediate beam energies. The level scheme of $^{70}$Kr was constructed from the observed $��$-ray transitions and coincidences. Tentative spin and parity assignments were made based on comparison with the mirror nucleus $^{70}$Se. A second $2^+$ state and a candidate for the corresponding $4^+_2$ state suggest shape coexistence in $^{70}$Kr. accepted Phys. Lett. B

We investigate low-lying fermion modes in SU(2) gauge theory at temperatures above the phase transition. Both staggered and overlap spectra reveal transitions from chaotic (random matrix) to integrable (Poissonian) behavior accompanied by an increasing localization of the eigenmodes. We show that the latter are trapped by local Polyakov loop fluctuations. Islands of such "wrong" Polyakov loops can therefore be viewed as defects leading to Anderson localization in gauge theories. We find strong similarities in the spatial profile of these localized staggered and overlap eigenmodes. We discuss possible interpretations of this finding and present a sparse random matrix model that reproduces these features. 11 pages, 23 plots in 11 figures; some comments and references added, some axis labels corrected; journal version

The s-process nucleosynthesis in Asymptotic giant branch (AGB) stars depends on the modeling of convective boundaries. We present models and s-process simulations that adopt a treatment of convective boundaries based on the results of hydrodynamic simulations and on the theory of mixing due to gravity waves in the vicinity of convective boundaries. Hydrodynamics simulations suggest the presence of convective boundary mixing (CBM) at the bottom of the thermal pulse-driven convective zone. Similarly, convection-induced mixing processes are proposed for the mixing below the convective envelope during third dredge-up (TDU), where the ${}^{13}{\rm{C}}$ pocket for the s process in AGB stars forms. In this work, we apply a CBM model motivated by simulations and theory to models with initial mass M = 2 and $M=3\,{M}_{\odot }$, and with initial metal content Z = 0.01 and Z = 0.02. As reported previously, the He-intershell abundances of ${}^{12}{\rm{C}}$ and ${}^{16}{\rm{O}}$ are increased by CBM at the bottom of the pulse-driven convection zone. This mixing is affecting the ${}^{22}\mathrm{Ne}$(α, n)${}^{25}\mathrm{Mg}$ activation and the s-process efficiency in the ${}^{13}{\rm{C}}$-pocket. In our model, CBM at the bottom of the convective envelope during the TDU represents gravity wave mixing. Furthermore, we take into account the fact that hydrodynamic simulations indicate a declining mixing efficiency that is already about a pressure scale height from the convective boundaries, compared to mixing-length theory. We obtain the formation of the ${}^{13}{\rm{C}}$-pocket with a mass of $\approx {10}^{-4}\,\,{M}_{\odot }$. The final s-process abundances are characterized by $0.36\lt [{\rm{s}}/\mathrm{Fe}]\lt 0.78$ and the heavy-to-light s-process ratio is $-0.23\lt [\mathrm{hs}/\mathrm{ls}]\lt 0.45$. Finally, we compare our results with stellar observations, presolar grain measurements and previous work.

Hippocampal activity patterns representing movement trajectories are reactivated in immobility and sleep periods, a process associated with memory recall, consolidation, and decision making. It is thought that only fixed, behaviorally relevant patterns can be reactivated, which are stored across hippocampal synaptic connections. To test whether some generalized rules govern reactivation, we examined trajectory reactivation following non-stereotypical exploration of familiar open-field environments. We found that random trajectories of varying lengths and timescales were reactivated, resembling that of Brownian motion of particles. The animals’ behavioral trajectory did not follow Brownian diffusion demonstrating that the exact behavioral experience is not reactivated. Therefore, hippocampal circuits are able to generate random trajectories of any recently active map by following diffusion dynamics. This ability of hippocampal circuits to generate representations of all behavioral outcome combinations, experienced or not, may underlie a wide variety of hippocampal-dependent cognitive functions such as learning, generalization, and planning.

International audience; SIRT1 regulates energy homeostasis by controlling the acetylation status and activity of a number of enzymes and transcriptional regulators. The fact that NAD(+) levels control SIRT1 activity confers a hypothetical basis for the design of new strategies to activate SIRT1 by increasing NAD(+) availability. Here we show that the deletion of the poly(ADP-ribose) polymerase-1 (PARP-1) gene, encoding a major NAD(+)-consuming enzyme, increases NAD(+) content and SIRT1 activity in brown adipose tissue and muscle. PARP-1(-)(/-) mice phenocopied many aspects of SIRT1 activation, such as a higher mitochondrial content, increased energy expenditure, and protection against metabolic disease. Also, the pharmacologic inhibition of PARP in vitro and in vivo increased NAD(+) content and SIRT1 activity and enhanced oxidative metabolism. These data show how PARP-1 inhibition has strong metabolic implications through the modulation of SIRT1 activity, a property that could be useful in the management not only of metabolic diseases, but also of cancer.

The aim of the Paper is to identify the types of short food supply chains (SFSCs), their spread today, and to demonstrate the advantages or disadvantages they provide, especially the logistical problems and solutions that can be identified in the chain. In order to achieve this goal, we carried out a review of international and Hungarian literature sources and secondary data. It can be stated that SFSCs can be a viable alternative to conventional supply chains pursuing a global distribution strategy. Establishing a restricted geographic range of supply provides several benefits to local producers, consumers and society. However, there are serious concerns about logistical costs and associated emissions. To overcome this, there is a need for compromises. The practical example we present shows that the use of conventional „less short” sales channels in the distribution mix is reasonable even in the case of local foods.