595 research outputs found

    Universal Reconfiguration of Facet-Connected Modular Robots by Pivots: The O(1) Musketeers

    Get PDF
    We present the first universal reconfiguration algorithm for transforming a modular robot between any two facet-connected square-grid configurations using pivot moves. More precisely, we show that five extra "helper" modules ("musketeers") suffice to reconfigure the remaining n modules between any two given configurations. Our algorithm uses O(n^2) pivot moves, which is worst-case optimal. Previous reconfiguration algorithms either require less restrictive "sliding" moves, do not preserve facet-connectivity, or for the setting we consider, could only handle a small subset of configurations defined by a local forbidden pattern. Configurations with the forbidden pattern do have disconnected reconfiguration graphs (discrete configuration spaces), and indeed we show that they can have an exponential number of connected components. But forbidding the local pattern throughout the configuration is far from necessary, as we show that just a constant number of added modules (placed to be freely reconfigurable) suffice for universal reconfigurability. We also classify three different models of natural pivot moves that preserve facet-connectivity, and show separations between these models

    Use of Computer Experiments to Study the Current Collected by Cylindrical Langmuir Probes

    Get PDF
    A particle-in-cell simulation has been developed to study the behaviour of ions in the surroundings of a negatively biased cylindrical Langmuir probe. Here, we report our findings on the transition between radial and orbital behaviour observed by means of the aforementioned code. The influence of the ion to electron temperature ratio on the transition for different dimensionless probe radius is discussed. Two different behaviours have been found for small and large probe radii

    Determination of genes involved in heat resistance response of Cronobacter sakazakii

    Get PDF
    Cronobacter sakazakii is considered an emerging opportunistic pathogen causing meningitis, septicaemia and enterocilitis in neonates, related to the use of contaminated Powdered Infant Formula (PIF). C. sakazakii has an unusual surviving ability under dry conditions and has been suggested to be one of the most thermotolerant members of the Enterobacteriaceae. It is necessary to understand the molecular mechanisms underlying the thermal resistance of C. sakazakii and may ultimately be useful in the development of control strategies in PIF factories. In the current study, a transposon mutagenesis approach was used to identify the genes involved in heat resistance. A total of 23 mutants were found corresponding to 12 different defective genes. Heat resistance of selected mutants were determined with the use of the thermoresistometer Mastia. Only 2 mutants had a greater sensitivity to heat compared with the heat resistance of the wild type. Genes identified to be involved in the cellular response to thermal treatments were Ribosome maturation protein RimP and Outer membrane Porin L (OmpL). The results suggest that the novo protein synthesis, and the use of cysteine for the formation of disulfide bonds for stabilization of proteins against denaturation during thermal treatments are key processes in the resistance against heat stress.The financial support of this research was provided by the Ministry of Science and Technology of the Spanish Government and European Regional Development Fund (ERDF) through Project AGL‐ 2010‐19775. J.P Huertas is grateful to the Spanish Ministry of Science and Innovation for his fellowship (BES‐2011‐046580). We acknowledge the funding received by Food for Health, Ireland under the grant number CC20080001 by Enterprise Ireland

    Influence of Environmental and Productive Factors on the Biodiversity of Lactic Acid Bacteria Population from Sheep Milk

    Get PDF
    Milk is a typical and satisfactory medium for the growth of lactic acid bacteria (LAB). These microorganisms are of vital importance in the quality of the milk since they contribute to its preservation and give differential organoleptic properties to the final product. Furthermore, LABs can act as biocontrol agents in the dairy industry by inhibiting the growth of undesirable bacteria present in milk and by improving the quality of dairy products such as cheese. In this context, knowing the transfer routes used by LABs from the livestock environment to the milk is of great importance within the dairy industry. Therefore, the objectives of the present study were to expand the knowledge of the LAB population present in the milk of Manchego ewe by means of DNA sequencing techniques and to evaluate the possible transfers of LAB species based on the management of each dairy farm. Samples of bulk tank milk, air (from the milking parlour and from the livestock housing), animal feed and teat surface (taken from 10 sheep per farm) were collected in 12 traditional livestock farms in Castilla-La Mancha (Spain), where each farm presented differences regarding their farming practices. A mixed-effects model was used to evaluate the effects of livestock practices on the distribution of LAB species. Results showed that the vast majority of species identified in the milk had an isolate that was also found in other matrices, which could indicate a microbial transference via the livestock environment to the milk. In addition, the mixed model showed that the factors that positively influence the LAB count were the low-line milking system and the daily use of acid detergent in cleaning the milking machine

    Improvement In Diagnosis And Treat-to-target Management Of Hyperuricemia In Gout: Results From The Gema-2 Transversal Study On Practice

    Get PDF
    The objective of the study was to evaluate changes regarding main European League Against Rheumatism (EULAR) recommendations on diagnosis and treatment of gout compared to a previous assessment. The GEMA-2 (Gout Evaluation and MAnagement) is a transversal assessment of practice for gout by rheumatologists. Main outcome variables were improvement of the previous GEMA assessment regarding the rate of crystal-proven diagnosis and that reaching therapeutic serum urate target below 6 mg/dl at last visit. Other management variables (prophylaxis, treatment of flares, lifestyle change advice) were also evaluated along with general characteristics. The sample was powered to include at least 483 patients for up to 50% change. Data on management of 506 patients were retrieved from 38 out of 41 rheumatology units that participated in the previous GEMA audit. Crystal-proved diagnosis rate increased from 26% to 32% (31% improvement) and was higher in gout-dedicated practices; ultrasonography contributed to diagnosis in less than 1% of cases. Therapeutic serum urate at last visit improved from 41% to 64% of all patients (66% of patients on urate-lowering medications), in any case over 50% improvement from the previous assessment. The use of any urate-lowering medication available was not prescribed as per label dosing in patients who failed to achieve target serum urate. Clinical inertia to increase doses of either allopurinol or febuxostat was still present in clinical practice. Over 50% improvement in targeting therapeutic serum urate has been observed, but clinical inertia is still present. Diagnosis is still mostly clinically based, ultrasonography not being commonly contributive. Menarini Espaa

    GluN2A NMDA Receptor Enhancement Improves Brain Oscillations, Synchrony, and Cognitive Functions in Dravet Syndrome and Alzheimer's Disease Models.

    Get PDF
    NMDA receptors (NMDARs) play subunit-specific roles in synaptic function and are implicated in neuropsychiatric and neurodegenerative disorders. However, the in vivo consequences and therapeutic potential of pharmacologically enhancing NMDAR function via allosteric modulation are largely unknown. We examine the in vivo effects of GNE-0723, a positive allosteric modulator of GluN2A-subunit-containing NMDARs, on brain network and cognitive functions in mouse models of Dravet syndrome (DS) and Alzheimer's disease (AD). GNE-0723 use dependently potentiates synaptic NMDA receptor currents and reduces brain oscillation power with a predominant effect on low-frequency (12-20 Hz) oscillations. Interestingly, DS and AD mouse models display aberrant low-frequency oscillatory power that is tightly correlated with network hypersynchrony. GNE-0723 treatment reduces aberrant low-frequency oscillations and epileptiform discharges and improves cognitive functions in DS and AD mouse models. GluN2A-subunit-containing NMDAR enhancers may have therapeutic benefits in brain disorders with network hypersynchrony and cognitive impairments

    Death kinetics of Escherichia coli in goat milk and Bacillus licheniformis in cloudberry jam treated by ohmic heating

    Get PDF
    In recent years, the world’s food industry has focused increasing attention on electrical techniques of food processing. Ohmic heating is one of these techniques that can be considered as a high temperature short time and a purely bulk heating method, having potential applications in processes such as blanching, evaporation and pasteurization in the food industry. However such technology would have to assure the microbiological safety obtained by the conventional cooking methods. Concerning this, the influence of heat treatment by ohmic and conventional technology on death kinetic parameters (D and z values) of Escherichia coli ATCCÂź 25922 was studied in goat milk. In ohmic treatment lower D values were obtained (D60ÂșC = 4.2 min, D63ÂșC = 1.9 min, D65ÂșC = 0.86 min) as compared to conventional treatment (D63ÂșC = 3.9 min, D65ÂșC = 3.5, D67ÂșC = 2.8 min, D75ÂșC = 1.5 min). The increase of temperature required for a ten fold decrease in D value was also lower in the ohmic inactivation (z = 8.4 ÂșC) comparing with the conventional inactivation (z = 23.1 ÂșC). The death kinetics for Bacillus licheniformis ATCCÂź 14580 spores in cloudberry jam were also studied under both types of heat inactivation (ohmic and conventional) and similar conclusions were drawn for the D values; lower D values were also obtained for ohmic treatment (D70ÂșC = 57.1 min, D75ÂșC = 25.2 min, D80ÂșC = 7.2 min) as compared to conventional treatment (D70ÂșC = 85.3 min, D75ÂșC = 51.0, D80ÂșC = 18.1 min, D85ÂșC = 6.0 min, D90ÂșC = 1.6 min). However, between the z values obtained for those treatments (z ohmic = 11.1 ÂșC and z conventional = 11.4 ÂșC) the differences were not significant. In general the results of present work indicate that the ohmic heating provides quicker death kinetics. This opens the perspective for shorter, less aggressive treatments

    New symmetrical quinazoline derivatives selectively induce apoptosis in human cancer cells

    Get PDF
    In the search of new symmetrical derivatives with anticancer activity, we have looked for novel compounds able to induce a selective proapoptotic mechanism in cancer cells. The potential antitumoral activity of several quinazoline derivatives was evaluated in vitro examining their cytotoxic effects against human breast, colon and bladder cancer cell lines. The IC(50) value of the compounds that showed cytotoxic activity was calculated. These compounds were tested for their ability to induce caspase-3 activation and nuclear chromatin degradation. Non-tumoral human cell lines were used to test the selectivity of the cytotoxic compounds against cancer cells. Several compounds showed no cytotoxicity in these cell lines. Finally, JRF12 (2,4-dibenzylaminoquinazoline) was chosen as the best candidate and its mechanism of action was studied in more detail. A time dependent evaluation of apoptosis was performed in the three cancer cell lines, followed by an evaluation of the cell cycle regulation involvement that showed a decrease of cells in G(1) phase and increase of cells in G(2) phase before cell death. 2,4-dibenzylaminoquinazoline treatment produces few changes in the expression of genes as evaluated by using oligonucleotide microarrays and Q-RT-PCR assays. In conclusion, 2,4-dibenzylaminoquinazoline is a promising anticancer drug showing cytostatic and apoptotic effects mainly in a transcription independent manner

    Measuring retail trade using card transactional data

    Get PDF
    En este trabajo se presenta un Índice de Comercio Minorista (ICM) de alta dimensionalidad construido para España, estimado a partir del uso de datos masivos. La informaciĂłn utilizada se corresponde con la que surge de las transacciones con tarjetas de crĂ©dito y de dĂ©bito de los clientes de BBVA en terminales de punto de venta (TPV) españoles. Los Ă­ndices obtenidos son robustos cuando se comparan con los que publica el Instituto Nacional de EstadĂ­stica (INE), tanto para el conjunto de España como para las distintas regiones y los diferentes canales de distribuciĂłn. Dando un paso mĂĄs, se calculan los Ă­ndices mensuales por provincias y por sectores (informaciĂłn no publicada por el INE) y se construye un Ă­ndice general diario. A partir de este Ășltimo Ă­ndice, se analizan ademĂĄs las pautas de consumo en alta frecuencia a travĂ©s de un modelo estructural de series temporalesIn this paper we present a high-dimensionality Retail Trade Index (RTI) constructed to nowcast the retail trade sector economic performance in Spain, using Big Data sources and techniques. The data are the footprints of BBVA clients from their credit or debit card transactions at Spanish point of sale (PoS) terminals. The resulting indexes have been found to be robust when compared with the Spanish RTI, regional RTI (Spain’s autonomous regions), and RTI by retailer type (distribution classes) published by the National Statistics Institute (INE). We also went one step further, computing the monthly indexes for the provinces and sectors of activity and the daily general index, by obtaining timely, detailed information on retail sales. Finally, we analyzed the high-frequency consumption dynamics using BBVA retailer behavior and a structural time series mode
    • 

    corecore