Glucose-sensitive holographic sensors for monitoring bacterial growth

A glucose sensor comprising a reflection hologram incorporated into a thin, acrylamide hydrogel film bearing the cis-diol binding ligand, 3-acrylamidophenylboronic acid (3-APB), is described. The diffraction wavelength (color) of the hologram changes as the polymer swells upon binding cis-diols. The effect of various concentrations of glucose, a variety of mono- and disaccharides, and the alpha-hydroxy acid, lactate, on the holographic response was investigated. The sensor displayed reversible changes in diffraction wavelength as a function of cis-diol concentration, with the sensitivity of the system being dependent on the cis-diol tested. The effect of varying 3-APB concentration in the hydrogel on the holographic response to glucose was investigated, and maximum sensitivity was observed at a functional monomer concentration of 20 mol %. The potential for using this holographic sensor to detect real-time changes in bacterial cell metabolism was demonstrated by monitoring the germination and subsequent vegetative growth of Bacillus subtilis spores.     

Does Local Television News Coverage Cultivate Fatalistic Beliefs About Cancer Prevention?

Many U.S. adults hold fatalistic beliefs about cancer prevention despite evidence that a large proportion of cancer deaths are preventable. We report findings from two studies that assess the plausibility of the claim that local television (TV) news cultivates fatalistic beliefs about cancer prevention. Study 1 features a content analysis of an October 2002 national sample of local TV and newspaper coverage about cancer. Study 2 describes an analysis of the 2005 Annenberg National Health Communication Survey (ANHCS). Overall, findings are consistent with the claim that local TV news coverage may promote fatalistic beliefs about cancer prevention. We conclude with a discussion of study implications for cultivation theory and the knowledge gap hypothesis and suggest foci for future research.     

Large-Scale Tracing of Ground Water with Sulfur Hexafluoride

Sulfur hexafluoride (SF6) was injected into a 9 km reach of the Santa Ana River in Orange County, CA, over a period of two weeks. The entire flow of this river, which averaged 2.8 m3 s?1, percolated into the ground in the field area. The tracer was monitored at wells near the river to determine subsurface flow patterns and flow times with an accuracy much greater than could be achieved using numerical simulations of ground-water flow. During the experiment, SF6 effectively tagged 3.7 × 106 m3 of water. The tracer plume was mapped in the subsurface for 18 months and indicates that linear ground-water velocities averaged about 2 km year?1. The tracer reached two wells adjacent to the river (about 200 m away) within three weeks, giving evidence that SF6 was not retarded significantly relative to the ground-water flow. This is in agreement with previous laboratory experiments.     

Consider Multiple Solutions

Design teams rarely consider multiple solution ideas before committing to one. They often forget that an even better idea could be just around the corner, and consider alternative ideas only when they don't like the current one. Using sketchboarding, design studio, or a combination of these two techniques can let teams quickly ideate over many solutions. They then have a chance to arrive at a solution that no one individual had thought of.     

Role of outcome conflict in dual-task interference.

The traditional explanation for dual-task interference is that tasks compete for scarce processing resources. Another possible explanation is that the outcome of the processing required for one task conflicts with the processing required for the other task (e.g., cross talk). To explore the contribution of outcome conflict to task interference, we manipulated the relatedness of the tasks. In Experiment 1, subjects searched concurrently for names of boys in one channel and names of cities in another channel. Responses were significantly delayed when nontarget on one channel belonged to, or was even just related to, the category designated as the target for the other channel. No comparable effects were found when the tasks were performed in isolation. Thus, the difficulty of the individual tasks is not the only determinant of how much they will interfere when combined, and there must be substantial interactions between processes carrying out the two tasks. In Experiment 2 subjects searched one channel for specific target letters and another channel for specific target digits. The nontargets in a channel were either from the same alphanumeric category as the targets for that channel or from the opposite category (i.e., the category of the targets for the other channel). It was found that although between-category search was more efficient than within-category search in single tasks, it was less efficient in dual tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

用于精确焊接的智能视觉系统

通过与其它传感技术的对比,简要分析了激光视觉在焊接生产中得到成功应用的原因。分析了早期激光视觉系统的特征和当时面临的挑战。介绍了Servo-Robot激光视觉的关键技术和已取得的显著进步,阐述了集成激光视觉的移动式便携焊接机器人和激光视觉在焊缝质量检测中的应用。展望了激光视觉系统的未来和智能视觉在提高机器人性能方面发展的显著进步,包括改进机器人人工示教、离线编程及视觉辅助机器人示教。     

Randomized trial of a gatekeeper program for suicide prevention: 1-year impact on secondary school staff.

Gatekeeper-training programs, designed to increase identification and referral of suicidal individuals, are widespread but largely untested. A group-based randomized trial with 32 schools examined impact of Question, Persuade, Refer (QPR) training on a stratified random sample of 249 staff with 1-year average follow-up. To test QPR impact, the authors introduced and contrasted 2 models of gatekeeper-training effects in a population: gatekeeper surveillance and gatekeeper communication. Intent-to-treat analyses showed that training increased self-reported knowledge (effect size [ES] = 0.41), appraisals of efficacy (ES = 1.22), and service access (ES = 1.07). Training effects varied dramatically. Appraisals increased most for staff with lowest baseline appraisals, and suicide identification behaviors increased most for staff already communicating with students about suicide and distress. Consistent with the communication model, increased knowledge and appraisals were not sufficient to increase suicide identification behaviors. Also consistent with the communication model were results from 2,059 8th and 10th graders surveyed showing that fewer students with prior suicide attempts endorsed talking to adults about distress. Skill training for staff serving as "natural gatekeepers" plus interventions that modify students' help-seeking behaviors are recommended to supplement universal gatekeeper training. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Evidence for terror management theory II: The effects of mortality salience on reactions to those who threaten or bolster the cultural worldview.

Three experiments were conducted to test the hypothesis, derived from terror management theory, that reminding people of their mortality increases attraction to those who consensually validate their beliefs and decreases attraction to those who threaten their beliefs. In Study 1, subjects with a Christian religious background were asked to form impressions of Christian and Jewish target persons. Before doing so, mortality was made salient to half of the subjects. In support of predictions, mortality salience led to more positive evaluations of the in-group member (the Christian) and more negative evaluations of the out-group member (the Jew). In Study 2, mortality salience led to especially negative evaluations of an attitudinally dissimilar other, but only among subjects high in authoritarianism. In Study 3, mortality salience led to especially positive reactions to someone who directly praised subjects' cultural worldviews and especially negative reactions to someone who criticized them. The implications of these findings for understanding in-group favoritism, prejudice, and intolerance of deviance are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)