Automated Parallelization of Discrete State-Space Generation

We consider the problem of generating a large state-space in a distributed fashion. Unlike previously proposed solutions that partition the set of reachable states according to a hashing function provided by the user, we explore heuristic methods that completely automate the process. The first step is an initial random walk through the state space to initialize a search tree, duplicated in each processor. Then, the reachability graph is built in a distributed way, using the search tree to assign each newly found state to classes assigned to the available processors. Furthermore, we explore two remapping criteria that attempt to balance memory usage or future workload, respectively. We show how the cost of computing the global snapshot required for remapping will scale up for system sizes in the foreseeable future. An extensive set of results is presented to support our conclusions that remapping is extremely beneficial.     

Hybrid photocatalytic membranes embedding decatungstate for heterogeneous photooxygenation

The incorporation of decatungstate in polymeric membranes provides new heterogeneous photocatalysts for the oxidation of organic substrates under oxygen atmosphere at 25 °C. Photocatalytic membranes have been prepared yielding polymeric films with a high thermal, chemical and mechanical stability (PVDF, PDMS, Hyflon). Surface spectroscopy techniques including transmittance and reflectance UV-Vis and FT-IR have been used to assess the photocatalyst integrity within the polymeric support. Catalyst screening has been performed under both homogeneous and heterogeneous photooxygenation conditions. The photocatalyst activity has been evaluated in terms of the substrate conversion, turnover numbers, and recycling experiments. A membrane induced selectivity behavior has been evidenced by comparison with homogeneous oxidations.     

EDEN: An Intelligent Software Environment for Diagnosis of Discrete-Event Systems

A software environment, called EDEN, that prototypes a recent approach to model-based diagnosis of discrete-event systems, is presented. The environment integrates a specification language, called SMILE, a model base, and a diagnostic engine. SMILE enables the user to create libraries of models and systems, which are permanently stored in the model base, wherein both final and intermediate results of the diagnostic sessions are hosted as well. Given the observation of a physical system gathered during its reaction to an external event, the diagnostic engine performs the a posteriori reconstruction of all the possible evolutions of the system over time and, then, draws candidate diagnoses out of them. The diagnostic method is described using a simplified example within the domain of power transmission networks. Strong points of the method include compositional modeling, support for model update, ability to focus on any sub-system, amenability to parallel execution, management of multiple faults, and broad notions of system and observation.     

剃齿刀的磨削

一直以来，齿轮热处理后的精加工一般采用磨削或珩磨这两项工艺，但剃齿加工工艺仍有现实意义。首先，剃齿总费用仅是磨削总费用的一部分；其次，剃齿加工所用循环时间要短得多，这就意味着剃齿加工投入的资金和必需的机床要少很多。另外，还要考虑到齿轮加工不可能都采用磨削加工，有些精度不高的齿轮不需要磨削加工，比如带台肩的齿轮，汽车的倒挡齿轮与一、二挡齿轮，所有农业机械的齿轮以及低速的传动齿轮。     

Symbolic computation of strongly connected components and fair cycles using saturation

The computation of strongly connected components (SCCs) in discrete-state models is a critical step in formal verification of LTL and fair CTL properties, but the potentially huge number of reachable states and SCCs constitutes a formidable challenge. We consider the problem of computing the set of states in SCCs or terminal SCCs in an asynchronous system. We employ the idea of saturation, which has shown clear advantages in symbolic state-space exploration (Ciardo et al. in Softw Tools Technol Transf 8(1):4–25, 2006; Zhao and Ciardo in Proceedings of 7th international symposium on automated technology for verification and analysis, pp 368–381, 2009), to improve two previously proposed approaches. We use saturation to speed up state exploration when computing each SCC in the Xie-Beerel algorithm, and we compute the transitive closure of the transition relation using a novel algorithm based on saturation. Furthermore, we show that the techniques we developed are also applicable to the computation of fair cycles. Experimental results indicate that the improved algorithms using saturation achieve a substantial speedup over previous BFS algorithms. In particular, with the new transitive closure computation algorithm, up to 10¹⁵⁰ SCCs can be explored within a few seconds.     

I2-Imidazoline Ligand CR4056 Improves Memory,Increases ApoE Expression and Reduces BBB Leakage in 5xFAD Mice

Recent evidence suggests that I2-imidazoline ligands have neuroprotective properties in animal models of neurodegeneration, such as Alzheimer’s disease (AD). We recently demonstrated that the I2-ligand BU224 reversed memory impairments in AD transgenic mice and this effect was not because of reductions in amyloid-β (Aβ) deposition. In this study, our aim was to determine the therapeutic potential of the powerful analgesic I2-imidazoline ligand CR4056 in the 5xFAD model of AD, since this ligand has been proven to be safely tolerated in humans. Sub-chronic oral administration of CR4056 (30 mg/kg for 10 days) led to an improvement in recognition memory in 6-month-old 5xFAD mice, but not in wild-type littermates, without affecting Aβ levels or deposition. Our results also revealed a change in the profile of microglia by CR4056, resulting in a suppression of pro-inflammatory activated microglia, but increased the density of astrocytes and the expression of ApoE, which is mainly produced by these glial cells. In addition, CR4056 restored fibrinogen extravasation, affecting the distribution of markers of astrocytic end feet in blood vessels. Therefore, these results suggest that CR4056 protects against Aβ-mediated neuroinflammation and vascular damage, and offers therapeutic potential at any stage of AD.     

Perception of Host Plant Volatiles in Hyalesthes obsoletus: Behavior, Morphology, and Electrophysiology

The Palearctic planthopper Hyalesthes obsoletus is the natural vector of the grapevine yellow disease Bois noir. Grapevine is an occasional host plant of this polyphagous planthopper. To deepen our knowledge of the role of plant volatile organic compounds for H. obsoletus host plant searching, we carried out behavioral, morphological, and electrophysiological studies. We tested the attraction of H. obsoletus to nettle, field bindweed, hedge bindweed, chaste tree, and grapevine by using a Y-shaped olfactometer. The results showed a significant attraction of male H. obsoletus to chaste tree, and of the females to nettle. Male H. obsoletus were repelled by odor from hedge bindweed. Ultrastructural studies of the antennae showed at least two types of olfactory sensilla at the antennal pedicel: plaque organs and trichoid sensilla. Volatile organic compounds from nettle and chaste tree were collected, and the extracts were analyzed by coupling gas-chromatography to both mass-spectrometry and electroantennography. The volatile organic compounds that elicited electrophysiological responses in male and female antennae were identified. These findings are discussed with respect to behavior of H. obsoletus males and females in the field.