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Neuronal SIRT1 Regulates Metabolic and Reproductive Function and the Response to Caloric Restriction.
Sirt1 is an NAD-dependent, class III deacetylase that functions as a cellular energy sensor. In addition to its well-characterized effects in peripheral tissues, emerging evidence suggests that neuronal Sirt1 activity plays a role in the central regulation of energy balance and glucose metabolism. In this study, we generated mice expressing an enzymatically inactive form (N-MUT) or wild-type (WT) SIRT1 (N-OX) in mature neurons. N-OX male and female mice had impaired glucose tolerance, and N-MUT female, but not male, mice had improved glucose tolerance compared with that of WT littermates. Furthermore, glucose tolerance was improved in all mice with caloric restriction (CR) but was greater in the N-OX mice, who had better glucose tolerance than their littermates. At the reproductive level, N-OX females had impaired estrous cycles, with increased cycle length and more time in estrus. LH and progesterone surges were absent on the evening of proestrus in the N-OX mice, suggesting a defect in spontaneous ovulation, which was confirmed by the ovarian histology revealing fewer corpora lutea. Despite this defect, the mice were still fertile when mated to WT mice on the day of proestrus, indicating that the mice could respond to normal pheromonal or environmental cues. When subjected to CR, the N-OX mice went into diestrus arrest earlier than their littermates. Together, these results suggested that the overexpression of SIRT1 rendered the mice more sensitive to the metabolic improvements and suppression of reproductive cycles by CR, which was independent of circadian rhythms
Role of the exchange and correlation potential into calculating the x-ray absorption spectra of half-metallic alloys: the case of Mn and Cu K-edge XANES in CuMnM (M = Al, Sn, In) Heusler alloys
This work reports a theoretical study of the x-ray absorption near-edge
structure spectra at both the Cu and the Mn K-edge in several CuMnM (M= Al,
Sn and In) Heusler alloys. Our results show that {\it ab-initio} single-channel
multiple-scattering calculations are able of reproducing the experimental
spectra. Moreover, an extensive discussion is presented concerning the role of
the final state potential needed to reproduce the experimental data of these
half-metallic alloys. In particular, the effects of the cluster-size and of the
exchange and correlation potential needed in reproducing all the experimental
XANES features are discussed.Comment: 15 pages, 5 figure
Discrimination and visualization of ELM types based on a probabilistic description of inter-ELM waiting times
Discrimination and visualization of different observed classes of edge-localized plasma instabilities (ELMs), using advanced data analysis techniques has been considered. An automated ELM type classifier which effectively incorporates measurement uncertainties is developed herein and applied to the discrimination of type I and type III ELMs in a set of carbon-wall JET plasmas. The approach involves constructing probability density functions (PDFs) for inter-ELM waiting times and global plasma parameters and then utilizing an effective similarity measure for comparing distributions: the Rao geodesic distance (GD). It is demonstrated that complete probability distributions of plasma parameters contain significantly more information than the measurement values alone, enabling effective discrimination of ELM type
Micropile Foundations in Karst: Static and Dynamic Testing Variability
Development of a major industrial facility required support of large loads from machine foundations. The site was underlain by highly variable karstic limestone conditions, which resulted in irregular depths to rock, very soft residual soil layers, and potential for voids in the rock and soil matrix. Foundation mats on micropiles were selected for support of the machines. The benefits associated with the micropiles were the speed of installation, and relative cost and schedule savings. Two load tests were performed before the start of micropile installation. One of these tests failed prematurely. A third test, performed during the initial stages of construction, also failed prematurely. Pile Driving Analyzer (PDA) testing of micropiles was used to investigate the capacity and variability of production piles that were already installed. The authors believe this may be the first application of the PDA technology to estimate the carrying capacity of micropiles bonded into rock. Because of the lack of previous experience in this application of PDA testing, suitable testing procedures needed to be developed in the field to reduce the potential for damage of the production micropiles, and to assess the accuracy of the tests. The results of the testing program showed that PDA testing may provide very accurate estimates of the capacity of micropiles bonded into rock. This paper discusses the techniques used for PDA testing of the micropiles, and compares the results of the PDA tests to the data from static load tests. The paper also contains a brief discussion on the site conditions, and the effect of the construction methods on the measured capacity of the micropiles and their variability
Partitioning qubits in hypergraph product codes to implement logical gates
The promise of high-rate low-density parity check (LDPC) codes to substantially reduce the overhead of fault-tolerant quantum computation depends on constructing efficient, fault-tolerant implementations of logical gates on such codes. Transversal gates are the simplest type of fault-tolerant gate, but the potential of transversal gates on LDPC codes has hitherto been largely neglected. We investigate the transversal gates that can be implemented in hypergraph product codes, a class of LDPC codes. Our analysis is aided by the construction of a symplectic canonical basis for the logical operators of hypergraph product codes, a result that may be of independent interest. We show that in these codes transversal gates can implement Hadamard (up to logical SWAP gates) and control-Z on all logical qubits. Moreover, we show that sequences of transversal operations, interleaved with error correction, allow implementation of entangling gates between arbitrary pairs of logical qubits in the same code block. We thereby demonstrate that transversal gates can be used as the basis for universal quantum computing on LDPC codes, when supplemented with state injection
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