Hierarchical CuO/ZnO “corn-like” architecture for photocatalytic hydrogen generation

Novel high efficient photocatalyst is the key for photocatalytic hydrogen generation from water splitting. In this study, a novel hierarchical CuO/ZnO “corn-like” architecture was designed and synthesized via a combination of hydrothermal and photodeposition method. The as-prepared nanostructured materials was shown to effectively generate hydrogen in the mixture of methanol and water (v/v = 1:10). This is because the hierarchical CuO/ZnO “corn-like” architecture: 1) greatly enhances the light utilization rate due to its special architecture, 2) enlarges the specific surface area, providing more reaction sites and promoting mass transfer, 3) promotes the photogenerated electrons transfer from ZnO to CuO, achieving the anti-recombination effect of electrons and holes, and 4) avoids the photocorrosion of ZnO to improve the stability of ZnO as a catalyst during water splitting. Moreover, the novel hierarchical CuO/ZnO “corn-like” architecture is easily recovered for reuse.     

Enhanced thermal stability of biomedical thermoplastic polyurethane with the addition of cellulose nanocrystals

Freeze‐dried cellulose nanocrystals (CNCs) were dispersed in the thermoplastic polyurethane [Pellethane 2363‐55D (P55D)] by a solvent casting method to fabricate CNC‐reinforced nanocomposites. This study demonstrated that the addition of small amounts (1–5 wt %) of CNCs to P55D increased the thermal degradation temperature while maintaining a similar stiffness, strength, and elongation of the neat P55D. CNC additions to P55D did not alter the glass‐transition temperature, but the onset decomposition temperature was shifted from 286 to 327°C when 1 wt % CNCs was dispersed in the matrix. The higher onset decomposition temperature was attributed to the formation of hydrogen bonds between the hydroxyl groups on the CNC surface and urethane groups in the hard block of P55D. The ultimate tensile strength and strain to failure (ε_f) of the nanocomposites were minimally affected by additions up to 5 wt % CNCs, whereas the elastic modulus was increased by about 70%. The observation that ε_f was unchanged with the addition of up to 5 wt % CNCs suggested that the flow/sliding of the hard blocks and chains were not hindered by the presence of the CNCs during plastic deformation. The ramifications of this study was that CNC additions resulted in wider processing temperatures of P55D for various biomedical devices while maintaining a similar stiffness, strength, and elongation. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41970.     

Tissue-level segmentation and tracking of cells in growing plant roots

With the spread of systems approaches to biological research, there is increasing demand for methods and tools capable of extracting quantitative measurements of biological samples from individual and time-based sequences of microscope images. To this end, we have developed a software tool for tissue level segmentation and automatic tracking of a network of cells in confocal images of the roots of the model plant Arabidopsis thaliana. The tool implements a novel hybrid technique, which is a combination of the recently developed Network Snakes technique and MCMC-based particle filters and incorporates automatic initialisation of the network snakes. A novel method of evaluation of network-structured multi-target tracking is also presented, and is used to evaluate the developed tracking framework for accuracy and robustness against several timelapse sequences of Arabidopsis roots. Evaluation results are presented, along with a comparison between the results of the component techniques and the hybrid approach. The results show that the hybrid approach performed consistently well at all levels of complexity and better than the component methods alone.     

Nonlinear control techniques for an atomic force microscope system

Two nonlinear control techniques are proposed for an atomic force microscope system. Initially, a learning-based control algorithm is developed for the microcantilever-sample system that achieves asymptotic cantilever tip tracking for periodic trajectories. Specifically, the control approach utilizes a learning-based feedforward term to compensate for periodic dynamics and high-gain terms to account for non-periodic dynamics. An adaptive control algorithm is then developed to achieve asymptotic cantilever tip tracking for bounded tip trajectories despite uncertainty throughout the system parameters. Simulation results are provided to illttstrate the efficacy and performance of the control strategies.     

Neural correlates of sexual arousal in homosexual and heterosexual men.

Men exhibit much higher levels of genital and subjective arousal to sexual stimuli containing their preferred sex than they do to stimuli containing only the nonpreferred sex. This study used event-related functional magnetic resonance imaging to investigate how this category-specific pattern would be reflected in the brains of homosexual (n = 11) and heterosexual (n = 11) men. Comparisons of activation to preferred sexual stimuli, nonpreferred sexual stimuli, and sports stimuli revealed large networks correlated with sexual arousal, spanning multiple cortical and subcortical areas. Both homosexual and heterosexual men exhibited category-specific arousal in brain activity. Within the amygdala, greater preference-related activity was observed in homosexual men, but it is unclear whether this is a cause or a consequence of their sexuality. In a subsequent analysis of regions hypothesized to support arousal, both participant groups demonstrated widespread increases in evoked activity for preferred stimuli. Aggregate data from these regions produced significant differences between stimulus types in 16 out of 22 participants. Significant activational differences matched reported sexual orientation in 15 of these 16 participants, representing an advance in psychophysiological measures of arousal. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Improving condom use intentions and behavior by changing perceived partner norms: An evaluation of condom promotion videos for college students.

Objective: To examine the effectiveness of 2 condom promotion videotapes on self-efficacy, intentions, and behavior. Design: Two hundred twenty college students completed social-cognitive and behavioral measures and were then randomly assigned to receive one of two 30-min condom promotion videotapes (male or female student presenters) or to a wait-list control condition. Participants who watched 1 of the videotapes completed immediate posttest measures, and 85% of participants completed a 4-month follow-up. Main Outcome Measures: Self-efficacy for condom use, intentions to use condoms, use of condom during last sex, and consistent condom use over the last month. Results: Participants who received either video reported greater self-efficacy to refuse to have unprotected sex and intentions than controls at follow-up. Individuals who received either video were more likely than controls to report using a condom during last sex with a regular partner, and those who watched the female presenter were more likely to report consistent condom use. Conclusion: Participants benefited in terms of self-efficacy and intentions from receiving either video, but both men and women benefited more in terms of condom use behavior from receiving the female video. Future research is needed to determine whether opposite-sex speaker videos could be beneficial with a larger (and more sexually active) sample and whether these effects are maintained over time. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Ethnic pride and self-control related to protective and risk factors: Test of the theoretical model for the strong African American families program.

Objective. To test a theoretical model of how ethnic pride and self-control are related to risk and protective factors. Design. A community sample of 670 African American youth (mean age = 11.2 years) were interviewed in households. Main Outcome Measures. Measures of cigarette smoking, alcohol use, and sexual behavior (lifetime to past month). Results. Structural modeling analyses indicated parenting was related to self-control and self-esteem, and racial socialization was related to ethnic pride. Self-control and self-esteem variables were related to levels of deviance-prone attitudes and to perceptions of engagers in, or abstainers from, substance use and sexual behavior. The proximal factors (behavioral willingness, resistance efficacy, and peer behavior) had substantial relations to the criterion variables. Participant gender and parental education also had several paths in the model. Results were generally similar for the 2 outcome behaviors. Conclusions. In this population, self-esteem and self-control are related to parenting approaches and have pathways to attitudes and social perceptions that are significant factors for predisposing to, or protecting against, early involvement in substance use and sexual behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Exploring aspects of cell intelligence with artificial reaction networks

The Artificial Reaction Network (ARN) is a Cell Signalling Network inspired connectionist representation belonging to the branch of A-Life known as Artificial Chemistry. Its purpose is to represent chemical circuitry and to explore computational properties responsible for generating emergent high-level behaviour associated with cells. In this paper, the computational mechanisms involved in pattern recognition and spatio-temporal pattern generation are examined in robotic control tasks. The results show that the ARN has application in limbed robotic control and computational functionality in common with Artificial Neural Networks. Like spiking neural models, the ARN can combine pattern recognition and complex temporal control functionality in a single network, however it offers increased flexibility. Furthermore, the results illustrate parallels between emergent neural and cell intelligence.     

Adapting wave-front algorithms to efficiently utilize systems with deep communication hierarchies

Large-scale systems increasingly exhibit a differential between intra-chip and inter-chip communication performance especially in hybrid systems using accelerators. Processor-cores on the same socket are able to communicate at lower latencies, and with higher bandwidths, than cores on different sockets either within the same node or between nodes. A key challenge is to efficiently use this communication hierarchy and hence optimize performance. We consider here the class of applications that contains wave-front processing. In these applications data can only be processed after their upstream neighbors have been processed. Similar dependencies result between processors in which communication is required to pass boundary data downstream and whose cost is typically impacted by the slowest communication channel in use. In this work we develop a novel hierarchical wave-front approach that reduces the use of slower communications in the hierarchy but at the cost of additional steps in the parallel computation and higher use of on-chip communications. This tradeoff is explored using a performance model. An implementation using the reverse-acceleration programming model on the petascale Roadrunner system demonstrates a 27% performance improvement at full system-scale on a kernel application. The approach is generally applicable to large-scale multi-core and accelerated systems where a differential in communication performance exists.     

KISTCM: knowledge discovery system for traditional Chinese medicine

Objective: Traditional Chinese Medicine (TCM) provides an alternative method for achieving and maintaining good health. Due to the increasing prevalence of TCM and the large volume of TCM data accumulated though thousands of years, there is an urgent need to efficiently and effectively explore this information and its hidden rules with knowledge discovery in database (KDD) techniques. This paper describes the design and development of a knowledge discovery system for TCM as well as the newly proposed KDD techniques integrated in this system.