Catechol-O-methyltransferase-deficient mice exhibit sexually dimorphic changes in catecholamine levels and behavior

Catechol-O-methyltransferase (COMT) is one of the major mammalian enzymes involved in the metabolic degradation of catecholamines and is considered a candidate for several psychiatric disorders and symptoms, including the psychopathology associated with the 22q11 microdeletion syndrome. By means of homologous recombination in embryonic stem cells, a strain of mice in which the gene encoding the COMT enzyme has been disrupted was produced. The basal concentrations of brain catecholamines were measured in the striatum, frontal cortex, and hypothalamus of adult male and female mutants. Locomotor activity, anxiety-like behaviors, sensorimotor gating, and aggressive behavior also were analyzed. Mutant mice demonstrated sexually dimorphic and region-specific changes of dopamine levels, notably in the frontal cortex. In addition, homozygous COMT-deficient female (but not male) mice displayed impairment in emotional reactivity in the dark/light exploratory model of anxiety. Furthermore, heterozygous COMT-deficient male mice exhibited increased aggressive behavior. Our results provide conclusive evidence for an important sex- and region-specific contribution of COMT in the maintenance of steady-state levels of catecholamines in the brain and suggest a role for COMT in some aspects of emotional and social behavior in mice.     

On the Black-Box Complexity of Sperner’s Lemma

We present several results on the complexity of various forms of Sperner’s Lemma in the black-box model of computing. We give a deterministic algorithm for Sperner problems over pseudo-manifolds of arbitrary dimension. The query complexity of our algorithm is linear in the separation number of the skeleton graph of the manifold and the size of its boundary. As a corollary we get an deterministic query algorithm for the black-box version of the problem 2D-SPERNER, a well studied member of Papadimitriou’s complexity class PPAD. This upper bound matches the deterministic lower bound of Crescenzi and Silvestri. The tightness of this bound was not known before. In another result we prove for the same problem an lower bound for its probabilistic, and an lower bound for its quantum query complexity, showing that all these measures are polynomially related. Research supported by the European Commission IST Integrated Project Qubit Application (QAP) 015848, the OTKA grants T42559 and T46234, and by the ANR Blanc AlgoQP grant of the French Research Ministry.     

Hybrid Recommender System Using Systolic Tree for Pattern Mining

A recommender system is an approach performed by e-commerce for increasing smooth users’ experience. Sequential pattern mining is a technique of data mining used to identify the co-occurrence relationships by taking into account the order of transactions. This work will present the implementation of sequence pattern mining for recommender systems within the domain of e-commerce. This work will execute the Systolic tree algorithm for mining the frequent patterns to yield feasible rules for the recommender system. The feature selection's objective is to pick a feature subset having the least feature similarity as well as highest relevancy with the target class. This will mitigate the feature vector's dimensionality by eliminating redundant, irrelevant, or noisy data. This work presents a new hybrid recommender system based on optimized feature selection and systolic tree. The features were extracted using Term Frequency-Inverse Document Frequency (TF-IDF), feature selection with the utilization of River Formation Dynamics (RFD), and the Particle Swarm Optimization (PSO) algorithm. The systolic tree is used for pattern mining, and based on this, the recommendations are given. The proposed methods were evaluated using the MovieLens dataset, and the experimental outcomes confirmed the efficiency of the techniques. It was observed that the RFD feature selection with systolic tree frequent pattern mining with collaborative filtering, the precision of 0.89 was achieved.     

On the Hitting Times of Quantum Versus Random Walks

The hitting time of a classical random walk (Markov chain) is the time required to detect the presence of—or equivalently, to find—a marked state. The hitting time of a quantum walk is subtler to define; in particular, it is unknown whether the detection and finding problems have the same time complexity. In this paper we define new Monte Carlo type classical and quantum hitting times, and we prove several relationships among these and the already existing Las Vegas type definitions. In particular, we show that for some marked state the two types of hitting time are of the same order in both the classical and the quantum case. Then, we present new quantum algorithms for the detection and finding problems. The complexities of both algorithms are related to the new, potentially smaller, quantum hitting times. The detection algorithm is based on phase estimation and is particularly simple. The finding algorithm combines a similar phase estimation based procedure with ideas of Tulsi from his recent theorem (Tulsi A.: Phys. Rev. A 78:012310 2008) for the 2D grid. Extending his result, we show that we can find a unique marked element with constant probability and with the same complexity as detection for a large class of quantum walks—the quantum analogue of state-transitive reversible ergodic Markov chains. Further, we prove that for any reversible ergodic Markov chain P, the quantum hitting time of the quantum analogue of P has the same order as the square root of the classical hitting time of P. We also investigate the (im)possibility of achieving a gap greater than quadratic using an alternative quantum walk. In doing so, we define a notion of reversibility for a broad class of quantum walks and show how to derive from any such quantum walk a classical analogue. For the special case of quantum walks built on reflections, we show that the hitting time of the classical analogue is exactly the square of the quantum walk.     

EXPLOITATION PROCEDURE BASED ON EIGENVECTOR REVISITED: THE CONCEPT OF WEIGHTED PREFERENCE FLOWS IN MULTICRITERIA OUTRANKING ANALYSIS

The outranking analysis has been frequently used to deal with the complex decisions involving qualitative criteria and imprecise data. So far, various versions of ELECTRE have been proposed for ranking alternatives in the outranking analysis. Among others, ELECTRE III has been widely used. A distillation procedure using a qualification index is proposed to rank alternatives from the fuzzy outranking relation. A weakness of ELECTRE III, however, is to involve the arbitrariness in the selection of the discrimination threshold function for the distillation procedure.

On the other hand, various variants of PROMETHEE has also been proposed for the outranking analysis. PROMETHEE intends to be simple and easy to understand. A deficiency of PROMETHEE is that it does not take discordance into account when the outranking relation matrix is constructed.

This note revisits an exploitation procedure based on eigenvector using the “weighted” preference in-and out-flows of each alternative in the outranking analysis. The basic idea is that it should be better to outrank a “strong” alternative than a “weak” one and, conversely, it is less serious to be outranked by a “strong” alternative than by a “weak” one in a PROMETHEE context. It has a completely different interpretation with the AHP (Analytic Hierarchy Process) since the components of the fuzzy (valued) outranking relation matrix are neither ratios nor reciprocal as in the AHP.     

Study of the feasibility of involving male student volunteers in case holding in an urban tuberculosis programme

AIMS: To investigate the effect of the angiotensin converting enzyme inhibitor, benazepril, on pulmonary function. METHODS: We investigated the influence of benazepril, on lung function and the interaction with inhaled salbutamol (0.1 to 6.6 mg) and histamine (0.03 to 30.69 g l-1) in normal subjects. Benazepril 20 mg, salbutamol 8 mg, propranolol 160 mg, and placebo were given orally once daily over 10 days. RESULTS: On day 8, there was no difference in the area under the salbutamol dose-response curves between benazepril, placebo and oral salbutamol (P > 0.05), propranolol shifted the curves to the right (P < 0.05). On day 10, histamine challenge resulted in following PD35sGaw values (geometric mean and 95% CI): with placebo 1.02 (0.95-1.09) g l-1, benazepril 1.04 (0.99-1.08), salbutamol 1.19 (1.13-1.25), propranolol 0.57 (0.50-0.65). CONCLUSIONS: Benazepril had no influence on baseline lung function, caused no interaction with inhaled salbutamol and the bronchial response to histamine was similar to placebo. However, our findings in normal subjects cannot be extrapolated automatically to asthmatics.     

Preparation and characterization of bismuth rare earth tungstate (BiREWO6) dielectric ceramics

BiREWO₆[RE=La, Nd, Pr, Sm, Gd, Dy, Tb, Yb, Y] ceramics have been prepared by the conventional solid-state ceramic route. The sintered samples are characterized by X-ray diffraction and SEM methods. The ceramics have high dielectric constants in the range 25–55 depending on the rare earth element. The dielectric losses of these ceramics increase with increase in the frequency and with increase in the rare earth crystal radii.     

Synthesis of urea-pyridyl ligand functionalized mesoporous silica hybrid material for hydrophobic and hydrophilic drug delivery application

In this work, we propose the synthesis of urea-pyridyl (UPy) ligand functionalized mesoporous silica hybrid material as novel and effective drug delivery system for loading/release of both hydrophobic and hydrophilic drugs. For the synthesis of UPy ligand functionalized mesoporous silica hybrid material, the combination of sol–gel co-condensation technique and post silica surface modification method were adapted. The prepared UPy ligand functionalized mesoporous silica hybrid (UPy-MSH) material was characterized by X-ray diffraction, Fourier-transform infrared, N₂ adsorption–desorption analysis. The material morphology and mesopore channels were observed by scanning and transmission electron microscopic analyses. The content of modified organic ligand functionalities present in the UPy-MSH material surface was determined by thermogravimetric analysis. The hydrophilic anticancer drug, 5-Fluorouracil and the hydrophobic anti-inflammatory drug, Ibuprofen was used as a model drugs to determine the loading and pH-responsive release efficiency of the synthesized UPy-MSH material under different pH (pH 7.4 and 5.0) conditions, respectively. In addition, the biocompatibility of the UPy-MSH material was evaluated on MDA-MB-231 cells. The experimental results depicted that the synthesized UPy-MSH material is biocompatible and has high drug loading capacity, selective and controlled release of specific drug with respect to the pH condition.     

Arsenic speciation and identification of monomethylarsonous acid and monomethylthioarsonic acid in a complex matrix

Anion-exchange chromatography was utilized for speciation of arsenite (As(III)), arsenate (As(V)), dimethylarsinic acid (DMA(V)), monomethylarsonic acid (MMA(V)), monomethylarsonous acid (MMA(III)), and the new As species monomethylthioarsonic acid (MMTA), using inductively coupled plasma mass spectrometric (ICPMS) detection. MMA(III) and MMTA were identified for the first time in freeze-dried carrot samples that were collected over 25 years ago as part of a joint U.S. EPA, U.S. FDA, and USDA study on trace elements in agricultural crops. The discovery of MMA(III) and MMTA in terrestrial foods necessitated the analytical characterization of synthetic standards of both species, which were used for standard addition in carrot extracts. The negative ion mode, high-resolution electrospray mass spectrometry (HR-ESI-MS) data produced molecular ions of m/z 122.9418 and 154.9152 for MMA(III) and MMTA, respectively. However, ESI-MS was not sensitive enough to directly identify MMA(III) and MMTA in the carrot extracts. Therefore, to further substantiate the identification of MMA(III) and MMTA, two additional separations using an Ion-120 column were developed using the more sensitive ICPMS detection. The first separation used 20 mM tetramethylammonium hydroxide at pH 12.2 with MMA(III) eluting in less than 7 min. In the second separation, MMTA eluted at 11.2 min by utilizing 40 mM ammonium carbonate at pH 9.0. Oxidation of MMA(III) and MMTA to MMA(V) with hydrogen peroxide was observed for standards and carrot extracts alike. Several samples of carrots collected from local markets in 2006 were also analyzed and found to contain low levels of inorganic arsenic species.