Seaweeds as a reservoir for diverse Vibrio parahaemolyticus populations in Japan

Gastroenteritis caused by Vibrio parahaemolyticus has recently been associated with foods prepared with seaweeds, but little is known about the bacterium's abundance and diversity among seaweeds in coastal environment. Therefore, we determined its phenotypic and genotypic diversity in relation to its seasonal abundance in seawater and seaweed samples from three areas of Kii Channel, Japan during June 2003 to May 2004. Isolates were obtained by selective enrichment of samples and detection of V. parahaemolyticus by colony hybridization with a species-specific probe. A total of 128 isolates comprising 16 from each source in each season were characterized by serotyping and ribotyping. V. parahaemolyticus was more abundant in seaweeds (3,762 isolates) than in water samples (2,238 isolates). Twenty and 17 serotypes were found among the selected seaweed and seawater isolates, respectively. Cluster analysis revealed 19, 11, 7 and 9 ribotypes during summer, autumn, winter and spring, respectively. Seaweeds supported a diverse V. parahaemolyticus population throughout the year and thus seaweeds are a reservoir for the organism. However, V. parahaemolyticus occurrence had positive correlation with water temperature and its abundance in seaweeds was at least 50 times higher during summer than in winter.     

Mechanical properties of aramid fiber reinforced polymer confined laminated bamboo lumber column under cyclic loading

European Journal of Wood and Wood Products - This paper explores the effect of using fiber-reinforced polymer (FRP) wrap on the hysteresis curve, skeleton curve, bearing capacity, stiffness and...     

Syngas production from ethanol dry reforming using Cu-based perovskite catalysts promoted with rare earth metals

This paper reports about the production of syngas from dry reforming of ethanol (EDR) upon LaCuO₃ and CeCuO₃ catalysts that were prepared by using citrate sol-gel method. EDRs were run with fresh catalyst at each varied variable and 42 L/g_cat/h of feed in a tubular reactor under atmospheric pressure. At equal feed pressure of reactants, steady state CO₂ conversion increased exponentially from 700 to 800 °C while H₂ and CO yields were increasing differently in sigmoid trend rendering H₂/CO ratios to drop linearly from 1.7 to 1.0. However, these reaction results except the latter are otherwise when ethanol-CO₂ ratio was increased (reducing CO₂ pressure) at 750 °C. A minimum H₂/CO ratio was evidenced at the ethanol-CO₂ ratio of 1.48. LaCuO₃ catalyst was more superior in producing syngas owing to its relatively low reduction temperature, high surface area and crystallinity, many active sites, good surface morphology and many C–O, C–H and hydroxyl groups.     

On universal transfer learning

In transfer learning the aim is to solve new learning tasks using fewer examples by using information gained from solving related tasks. Existing transfer learning methods have been used successfully in practice and PAC analysis of these methods have been developed. But the key notion of relatedness between tasks has not yet been defined clearly, which makes it difficult to understand, let alone answer, questions that naturally arise in the context of transfer, such as, how much information to transfer, whether to transfer information, and how to transfer information across tasks. In this paper, we look at transfer learning from the perspective of Algorithmic Information Theory/Kolmogorov complexity theory, and formally solve these problems in the same sense Solomonoff Induction solves the problem of inductive inference. We define universal measures of relatedness between tasks, and use these measures to develop universally optimal Bayesian transfer learning methods. We also derive results in AIT that are interesting by themselves. To address a concern that arises from the theory, we also briefly look at the notion of Kolmogorov complexity of probability measures. Finally, we present a simple practical approximation to the theory to do transfer learning and show that even these are quite effective, allowing us to transfer across tasks that are superficially unrelated. The latter is an experimental feat which has not been achieved before, and thus shows the theory is also useful in constructing practical transfer algorithms.     

Effects of feedback control on chaotic convection in fluid-saturated porous media

Thermal convective instability in a fluid-saturated porous layer heated from below and cooled from above is investigated theoretically using dynamical systems approach. A feedback control strategy with an array of sensors situated at the top plate of the fluid layer is adopted. The Galerkin truncated approximation is employed to derive a low dimensional Lorenz-like model. It is shown that suppression or enhancement of chaotic convection is possible via feedback control.     

确定不均匀温度作用下梁柱塑性轴力-弯矩承载力曲线的简化方法

受约束钢杆,当暴露在火中时,会产生作用力,并将梁或柱的反应转化为梁-柱反应。通过轴力-弯矩承载力曲线(P-M曲线)确定梁-柱的极限承载力。规范推荐使用平均温度来确定高温下的P-M曲线。该假定适用于钢材温度均匀的情况,如:4面都暴露于火中的柱,但不能用于1、2或3面暴露于火中的柱,因为截面上存在温差。温差导致P-M曲线严重歪曲,基于均匀温度假定的承载力曲线不能用于确定这类梁-柱的极限承载力。调整均匀温度作用下塑性P-M曲线,以考虑温差引起的形状变化。首先,计算横截面上的温度;然后,通过调整基于平均温度的P-M曲线计算扭曲的P-M曲线。用算例演示了该方法在设计中的应用,结果表明,该方法适用于确定不均匀温度作用下梁-柱的极限承载力。     

Memory bandwidth analysis of hierarchical multiprocessors usingmodel decomposition and steady-state flow analysis

For memory bandwidth analysis, researchers generally discard requests that are not accepted during a memory cycle. This assumption simplifies the analysis and produces negligible discrepancies with actual results for a system with a non-hierarchical interconnection network. However, the assumption, “the requests that are not occupied during a memory cycle are discarded,” cannot be used for a multiprocessor system with a hierarchical interconnection network (HIN), because the error introduced assumption can be several orders of magnitude higher than the actual bandwidth. An improved analytical model to determine the bandwidth of a HIN-based system is presented     

Error analysis of digital phase measurement of distorted waves

An analysis of errors associated with the digital measurement of phase angle between two signals, one of which may be distorted by a harmonic, is presented. All the results were found by running a simulation program on a VAX 11/780 computer. The results are very useful for the users of the phase meters. This technique may introduce large errors for some particular types of input waves. The main purpose of this work is to explain how large the error could be under certain conditions on the input waves     

Intraoperative pacemaker dysfunction caused by the use of electrocautery during a total hip arthroplasty

PURPOSE: To evaluate if there is a seasonal pattern to the incidence of endogenous uveitis in south-western Finland with special reference to acute anterior uveitis. METHODS: The incidence rates per month of the 414 new uveitis cases from years 1980-82 and 1988 in the district of Turku University Hospital were calculated. The months of the year were grouped into warm (June to September), transitional (April, May, October, November), and cold (December to March) seasons based on the mean air temperature of the months in Turku. RESULTS: We observed a statistically significant increase in the incidence of all uveitis cases in the warm and transitional seasons compared with the cold season (p=0.030 and p=0.008 respectively). A similar seasonal trend was found among anterior uveitis cases, but not among the intermediate, posterior or panuveitis cases. The incidence of acute anterior uveitis cases was higher in the transitional than in the cold season (p=0.025). No seasonal variation of the incidence was found in the subgroup of acute anterior uveitis where ankylosing spondylitis had been confirmed (p=0.70). CONCLUSION: The present data suggests that there is seasonal variation of the incidence of uveitis in south-western Finland.     

An empirical study of dynamic properties of an individual carbon nanotube electron source system

In this paper we present an empirical study of some dynamic properties of an individual carbon nanotube (CNT) field emission electron source system. We propose a circuit model that represents the CNT cathode to anode diode as a capacitor in parallel with a voltage-controlled variable resistor. The transient response of the CNT electron source system to the falling edge of a voltage step input was evaluated. For input voltages below the threshold voltage for field emission, the nanotube loop is effectively open and the circuit response is consistent with a discharging capacitor. On the other hand, for input voltages above field emission threshold, the nanotube loop conducts and now the capacitor discharges to a certain extent through the nanotube loop as well. Field emission current versus voltage data also shows that the resistance across the CNT cathode to anode diode varies as a function of applied voltage. Below turn-on voltage, the diode behaves as an open circuit (4 TΩ at the ammeter noise floor). Above turn-on voltage, resistance falls exponentially, as expected from the Fowler–Nordheim equation for cold field emission current. Experimental current–voltage data is presented for a simple emitter array consisting of two CNTs with equal lengths. Despite the similarity in their lengths the turn-on voltages of the nanotubes varied significantly, viz. 26 V versus 109 V. This large difference in the turn-on voltages can be attributed to tip imperfections. For advanced array applications such as high-throughput parallel e-beam lithography, in which precise dose control is necessary, the diode circuit model will be useful for controlling individually addressed nanotubes to account for dissimilar field emission properties. The model may also be applied to optimize the design of a SEM incorporating a single CNT electron source.