Serotonin Promotes Serum Albumin Interaction with the Monomeric Amyloid β Peptide

Prevention of amyloid β peptide (Aβ) deposition via facilitation of Aβ binding to its natural depot, human serum albumin (HSA), is a promising approach to preclude Alzheimer’s disease (AD) onset and progression. Previously, we demonstrated the ability of natural HSA ligands, fatty acids, to improve the affinity of this protein to monomeric Aβ by a factor of 3 (BBRC, 510(2), 248–253). Using plasmon resonance spectroscopy, we show here that another HSA ligand related to AD pathogenesis, serotonin (SRO), increases the affinity of the Aβ monomer to HSA by a factor of 7/17 for Aβ₄₀/Aβ₄₂, respectively. Meanwhile, the structurally homologous SRO precursor, tryptophan (TRP), does not affect HSA’s affinity to monomeric Aβ, despite slowdown of the association and dissociation processes. Crosslinking with glutaraldehyde and dynamic light scattering experiments reveal that, compared with the TRP-induced effects, SRO binding causes more marked changes in the quaternary structure of HSA. Furthermore, molecular docking reveals distinct structural differences between SRO/TRP complexes with HSA. The disintegration of the serotonergic system during AD pathogenesis may contribute to Aβ release from HSA in the central nervous system due to impairment of the SRO-mediated Aβ trapping by HSA.     

Analysis of thermal processes in piezoceramic actuator

An analytical expression has been derived to calculate the temperature in the bulk of a piezoelectric cell and on its surface with allowance made for the distributed heat release. It is experimentally shown that the temperature at the center of actuator exceeds the temperature on its surface by 10–40°C and reaches 50–140°C under specific loads of 50–100 W/cm³. The reason for this is that up to 25–45% of the supplied energy is transformed into heat. It is established that the main cause of actuator failure is electric breakdown and exfoliation of passive ceramic layers.     

Excitation of the uranyl ion in U(IV) oxidation with xenon difluoride in frozen aqueous sulfuric acid solutions: III. Effect of solvent deuteration

The effect of the solvent deuteration on the reaction of U(IV) with XeF₂ in solutions of H₂SO₄ in H₂O and D₂SO₄ in D₂O, occurring in the course of heating these solutions after their quick cooling (10–15 K s^?1) to 77 K, was examined. The effect is manifested in essentially different temperature dependences of the chemiluminescence accompanying the oxidation of U(IV) with XeF₂. The results obtained are interpreted within the framework of the concept that the low-temperature reaction of U(IV) with XeF₂ is catalyzed by the juvenile surface of crystal hydrates of sulfuric and deuterosulfuric acids, formed in the course of low-temperature phase transitions. The isotope effect is due to different kinetics of the phase transitions in solutions of H₂SO₄ in H₂O and D₂SO₄ in D₂O. In the course of crystallization of supercooled H₂SO₄ solutions, depending on the mode of temperature variation, either one or two eutectics appreciably differing in the physical properties are formed. In the course of crystallization of supercooled solutions of D₂SO₄ in D₂O, one stable eutectic is formed in each sample, and its characteristics depend on the thermal history of the sample. The eutectics melt in the course of heating of the frozen solution at temperatures differing by only 3–4 K.     

Extending constraint logic programming for temporal reasoning

In recent years, several constraint‐based temporal reasoning frameworks have been proposed. They consider temporal points or intervals as domain elements linked by temporal constraints. Temporal reasoning in these systems is based on constraint propagation. In this paper, we argue that a language based on constraint propagation can be a suitable tool for expressing and reasoning about temporal problems. We concentrate on Constraint Logic Programming (CLP) which is a powerful programming paradigm combining the advantages of Logic Programming and the efficiency of constraint solving. However, CLP presents some limitations in dealing with temporal reasoning. First, it uses an “arc consistency” propagation algorithm which is embedded in the inference engine, cannot be changed by the user, and is too weak in many temporal frameworks. Second, CLP is not able to deal with qualitative temporal constraints. We present a general meta CLP architecture which maintains the advantages of CLP, but overcomes these two main limitations. Each architectural level is a finite domain constraint solver(CLP(FD)) that reasons about constraints of the underlying level. Based on this conceptual architecture, we extend the CLP(FD)language and we specialize the extension proposed on Vilain and Kautz’sPoint Algebra, on Allen’s Interval Algebra and on the STP framework by Dechter, Meiri and Pearl. In particular, we show that we can cope effectively with disjunctive constraints even in an interval‐based framework. This revised version was published online in June 2006 with corrections to the Cover Date.     

基于LabMap的卡尔曼滤波器的应用

LabMap是自动控制领域的一种软件中间件,本文利用它的虚拟寄存器直接在中间件层面实现了卡尔曼滤波算法,而不改变分布式系统的其它构件.实验证明该卡尔曼滤波能在一定程度上去除辅助驾驶系统中速度信号的噪声.     

Belief revision via Lamarckian evolution

We present a system for performing belief revision in a multi-agent environment. The system is called GBR (Genetic Belief Revisor) and it is based on a genetic algorithm. In this setting, different individuals are exposed to different experiences. This may happen because the world surrounding an agent changes over time or because we allow agents exploring different parts of the world. The algorithm permits the exchange of chromosomes from different agents and combines two different evolution strategies, one based on Darwin’s and the other on Lamarck’s evolutionary theory. The algorithm therefore includes also a Lamarckian operator that changes the memes of an agent in order to improve their fitness. The operator is implemented by means of a belief revision procedure that, by tracing logical derivations, identifies the memes leading to contradiction. Moreover, the algorithm comprises a special crossover mechanism for memes in which a meme can be acquired from another agent only if the other agent has “accessed” the meme, i.e. if an application of the Lamarckian operator has read or modified the meme. Experiments have been performed on the η-queen problem and on a problem of digital circuit diagnosis. In the case of the η-queen problem, the addition of the Lamarckian operator in the single agent case improves the fitness of the best solution. In both cases the experiments show that the distribution of constraints, even if it may lead to a reduction of the fitness of the best solution, does not produce a significant reduction. Evelina Lamma, Ph.D.: She is Full Professor at the University of Ferrara. She got her degree in Electrical Engineering at the University of Bologna in 1985, and her Ph.D. in Computer Science in 1990. Her research activity centers on extensions of logic programming languages and artificial intelligence. She was coorganizers of the 3rd International Workshop on Extensions of Logic Programming ELP92, held in Bologna in February 1992, and of the 6th Italian Congress on Artificial Intelligence, held in Bologna in September 1999. Currently, she teaches Artificial Intelligence and Fondations of Computer Science. Fabrizio Riguzzi, Ph.D.: He is Assistant Professor at the Department of Engineering of the University of Ferrara, Italy. He received his Laurea from the University of Bologna in 1995 and his Ph.D. from the University of Bologna in 1999. He joined the Department of Engineering of the University of Ferrara in 1999. He has been a visiting researcher at the University of Cyprus and at the New University of Lisbon. His research interests include: data mining (and in particular methods for learning from multirelational data), machine learning, belief revision, genetic algorithms and software engineering. Luís Moniz Pereira, Ph.D.: He is Full Professor of Computer Science at Departamento de Informática, Universidade Nova de Lisboa, Portugal. He received his Ph.D. in Artificial Intelligence from Brunel University in 1974. He is the director of the Artificial Intelligence Centre (CENTRIA) at Universidade Nova de Lisboa. He has been elected Fellow of the European Coordinating Committee for Artificial Intelligence in 2001. He has been a visiting Professor at the U. California at Riverside, USA, the State U. NY at Stony Brook, USA and the U. Bologna, Italy. His research interests include: knowledge representation, reasoning, learning, rational agents and logic programming.     

Kinetics and Mechanism of Thermal Decomposition of Dinitramide

Kinetics of the thermal decomposition of dinitramide (HDN) in aqueous solutions and of NH₄N(NO₂)₂ (ADN) and KN(NO₂)₂ (KDN) in sulfuric acid, nitric acid and anhydrous acetic acid solutions was studied. The species N(NO₂)₋₂, HN(NO₂)₂ and H₂N(NO₂) were established to take part in the decomposition over a wide range of the medium acidity. Kinetic regularities of their thermal decomposition were determined. The role of the decomposition of dinitramide at the initial and self-acceleration stages of the decomposition of ADN was determined. The most likely mechanism of the decomposition of dinitramide, N(NO₂)₋₂ and H₂N(NO₂)₊₂ was proposed.     

Use of smoothing splines and rapid Fourier transformation for constructing periodic differentiable approximations of discrete signals

A method of thinning out voltage and current discrete signals for electromagnetic alternating current systems using smoothing splines followed by use of rapid Fourier transformation in order to obtain periodic differentiable approximations is used. It is shown that use of some splines may be regarded as a method of smoothing by frequency windows. __________ Translated from Izmeritel’naya Tekhnika, No. 7, pp. 26–29, July, 2006.     

Magnetic crystallographic anisotropy of Fe/GaAs(100) epitaxial films

An investigation was made of the anisotropic properties of Fe films obtained by molecular-beam epitaxy on GaAs(100) substrates. It is shown that at thicknesses t=40–50 Å the Fe films begin to exhibit cubic magnetic anisotropy. At thicknesses t>100 Å the first constant of cubic anisotropy K₁ has values similar to those for “bulk” Fe single crystals. Films of intermediate thickness 50<t<100 Å possess both isotropic and anisotropic phases. Pis’ma Zh. Tekh. Fiz. 25, 88–95 (January 26, 1999)