Long latency evoked potentials in a case of corpus callosum agenesia

Following monoaural stimulation, long latency auditory evoked potentials (LLAEPs) recorded from contralateral temporal areas have a shorter latency and larger amplitude than those recorded from the ipsilateral temporal areas. This observation agrees with the operational model drawn up in 1967 by Kimura, which assumes that only anatomically prevailing crossed auditory pathways are active during dichotic hearing, while direct pathways are inhibited. The inputs may then be conveyed to the contralateral cortex, from where they finally reach the ipsilateral temporal areas by means of interhemispheric commissures. It is this mechanism which may underline the right ear advantage for verbal stimuli and the left ear advantage for melodies observed when administering dichotic listening tasks. With the aim of verifying this hypothesis, we recorded temporal LLAEPs in a 21 year-old woman suffering from complex partial seizures, whose CT scan and MRI showed corpus callosum agenesia. Our data support the hypothesis that ipsilateral pathways are greatly inhibited by the contralateral pathways, and therefore auditory stimuli can be supposed to reach the contralateral auditory cortex from where they are transferred through the corpus callosum to the ipsilateral auditory cortex.     

Purely neural,rule-based diagnostic systems. II. Uncertain reasoning

This article describes neural mechanisms for carrying out forms of uncertain reasoning that are frequently applied in diagnostic problem-solving. These include various sorts of causal and probabilistic reasoning, as well as the updating of certainty measures. the control and synchronization functions that are needed to schedule these inferential processes are carried out by a neural network, too. A concluding section is devoted to discussing the role of learning in neural diagnostic systems. © 1995 John Wiley & Sons, Inc.     

带热浸铝涂层MANET Ⅱ马氏体钢的氢渗透性能研究

在300～450℃温度范围内,分别在氢气相和液态铅锂合金相中,开展了带热浸铝涂层MANET Ⅱ马氏体钢的氢渗透性能研究.结果表明,实验所得到的氢渗透率减低因子(PRF),在气相中为620～263,在液态铅锂合金相中为45～30.但仍然没有满足DEMO聚变堆的设计要求.涂层的自修复效应在400 ℃以上是明显和有效的.从渗透通量与样品上游氢压的关系来看,涂层使得表面效应对渗透过程的影响很大.在上游小流量及在液态铅锂合金中鼓泡充氢可以导致渗透通量升高.扫描电镜和能谱分析(SEM-EDS)的结果表明,样品表面被液态铅锂合金所浸润的部分出现微裂纹,而未浸润部分没有出现微裂纹.微裂纹很肤浅,仅仅影响涂层的最外表面薄层,没有贯穿整个渗铝层而到达基体.未浸润表面的Al/O原子比约为2/3,浸润表面约为1/1,表明液态铅锂合金对渗铝层表面的Al2O3薄层造成了损伤.总的看来,造成氢渗透阻挡层性能退化的原因,是涂层外表面与液态铅锂合金相互作用,以及涂层在升、降温过程中产生热应力释放.     

Local buckling loads of sandwich panels made with laminated faces

The paper is devoted to assessing the optimal arrangements of hybrid laminated faces of sandwich panels in order to maximize local buckling loads corresponding to the wrinkling of compressed faces. The analysis is carried out by modelling compressed faces as thin unsymmetric laminates resting on elastic two-parameter foundations. The First-order Shear Deformation Theory, in conjunction with the Rayleigh-Ritz method, has been used to evaluate buckling loads of simply supported flat laminates subjected to in-plane biaxial compression and shear forces. A numerical investigation is intended to support evidence for the influence of laminate parameters (fibre orientation, geometrical dimensions) and foundation parameters (modulus of subgrade reaction and shear modulus); obtained results are reported and discussed in the paper.     

Relativized perfect zero knowledge is not BPP

In this paper we further study the complexity of zero-knowledge interactive proofs. We prove that there is an oracle A such that there is a language L which is recognizable by a two round, perfect zero-knowledge interactive proof relative to A, but such that L BPP^A. This gives interesting implications for what can be demonstrated about zero-knowledge interactive proofs using standard methods.     

Discovery of novel anticancer compounds based on a quinoxalinehydrazine pharmacophore

Quinoxalinehydrazines represent a novel class of compounds with excellent potency in a panel of cancer cell lines. A prototype compound, SC144, showed significant in vivo efficacy in mice xenograft models of human breast cancer cells. The subsequent structure-activity relationship study resulted in the discovery of SC161 with better potency in cancer cell lines. Further exploring the possible conformational space by a 10 ns molecular dynamics simulation as presented herein, resulted in various pharmacophore orientations. The trajectory analysis indicated that in most of the simulation time, the molecule stays favorably in a compact planarlike orientation. We therefore built a pharmacophore model based on the cluster containing the highest number of frames to represent the most probable orientation. The model was used to screen a subset of our small molecule database containing 350,000 compounds. We selected 35 compounds for the initial cytotoxicity screen. Seventeen compounds belonging to oxadiazolopyrazine and quinoline class displayed cytotoxicity in various cancer cell lines. Five of them, compounds 2, 6, 15, 16, and 19, all bearing an oxadiazolopyrazine scaffold, showed IC(50) values <3 muM in certain tumor cell lines. The most potent compound, 2, showed IC(50) values <2 muM in HCT116 p53(+/+), HCT116 p53(-/-), and HEY cells, and 8 muM in NIH3T3 cells. This study shows that conformational sampling of a lead small molecule followed by representative pharmacophore model development is an efficient approach for the rational design of novel anticancer agents with similar or better potency than the original lead but with different physicochemical properties.     

The ITER EC H&CD upper launcher: Structural system

After approval of the preliminary design of the ITER EC H&CD Upper Launcher, ECHUL-CA, a consortium of several European research institutes, was founded to pool resources for approaching the final design. At the end of 2011 the consortium has signed a 2 years contract with F4E to go ahead with the work on the launcher. The contract deals with design work on both the port plug, forming the structural system, and the mm-wave-system, which injects the RF-power into the plasma. Within the period of this contract all components being part of the Tritium confinement, of which the closure plate, the support flange, the diamond windows and the waveguide feed-throughs are the most outstanding ones, will get the status of the final design.Important steps to be done for the structural system are the optimization of the mechanical behavior of the launcher, leading to minimum deflections of the port plug during plasma disruptions and optimum seismic resistance. To reduce the effect of halo currents it was decided to recess the first wall of 100 mm compared to the regular blanket tangent. This recess requires substantial changes of the cooling system and the thermo-hydraulic design of the launcher. Also the layout of the shielding arrangement and the integration of the mm-wave system need significant revision. Moreover manufacturing aspects and enhanced remote handling capability are taken into account.For the final design also quality aspects must be considered; thus the design is elaborated with respect to applicable codes and standards, material specifications, risk analyses and the RAMI (reliability, availability, maintainability and inspectability) analysis to guarantee maximum performance of the device.This paper outlines the present status of the structural system of the EC H&CD upper launcher and represents the most recent steps towards its final design.     

The European contribution to the development and validation activities for the design of IFMIF lithium facility

The International Fusion Materials Irradiation Facility (IFMIF) is an accelerator-driven intense neutron source where candidate materials for fusion reactors will be tested and validated. The high energy neutron flux is produced by means of two deuteron beams (total current of 250 mA, energy of 40 MeV) that strikes a liquid lithium target circulating in a lithium loop of IFMIF plant. The European (EU) contribution to the development of the lithium facility comprises five procurement packages, as follow: (1) participation to the experimental activities of the EVEDA lithium test loop in Oarai (Japan); (2) study aimed at evaluating the corrosion and erosion phenomena, promoted by lithium, for structural fusion reference materials like AISI 316L and Eurofer; (3) design and validation of the lithium purification method with the aim to provide input data for the design of the purification system of IFIMF lithium loop; (4) design and validation of the remote handling (RH) procedures for the refurbishment/replacement of the EU concept of IFMIF target assembly including the design of the remote handling tools; (5) the engineering design of the European target assembly for IFMIF and the safety and RAMI analyses for the entire IFMIF lithium facility.The paper gives an overview of the status of the activities and of the main outcomes achieved so far.     

How Important Are Genes to Achieve Longevity?

Several studies on the genetics of longevity have been reviewed in this paper. The results show that, despite efforts and new technologies, only two genes, APOE and FOXO3A, involved in the protection of cardiovascular diseases, have been shown to be associated with longevity in nearly all studies. This happens because the genetic determinants of longevity are dynamic and depend on the environmental history of a given population. In fact, population-specific genes are thought to play a greater role in the attainment of longevity than those shared between different populations. Hence, it is not surprising that GWAS replicated associations of common variants with longevity have been few, if any, as these studies pool together different populations. An alternative way might be the study of long-life families. This type of approach is proving to be an ideal resource for uncovering protective alleles and associated biological signatures for healthy aging phenotypes and exceptional longevity.