Diagnostic test evaluation of a nasal flow monitor for obstructive sleep apnea detection in sleep apnea research

In this diagnostic test evaluation of a nasal flow monitoring device for obstructive sleep apnea (OSA), 34 patients referred for polysomnography were studied at home for three consecutive nights with the monitor. The mean age of subjects (+/-SD) was 41.9+/-10.3 years, and their mean apnea-hypopnea index (AHI) was 31.5+/-27.2. The difference between the average AHI from three nights at home on the monitor and the polysomnogram (PSG) result was 1.8+/-17.1. The area under the receiver operating characteristic curve (AUC) for PSG AHI > or = 10 was .96. With a threshold AHI of 18 on the flow monitor, sensitivity was .92, specificity .86, positive predictive value .96, and negative predictive value .75. For detecting severe OSA (AHI > or = 30), the AUC was .85. With knowledge of appropriate thresholds and the pretest risk of OSA, the flow monitor can be used to detect or exclude OSA for sleep-related research, as well as to identify severe cases needing priority for further evaluation.     

Examples of real world engineering ethics problems

Nine examples are presented illustrating the kinds of problems encountered in actual practice by conscientious engineers. These cases are drawn fom the records of the IEEE Ethics Committee, and from the experience of the ethics help-line initiated recently by the Online Ethics Center for Engineering and Science. They range from situations in which companies try to cheat one another to those in which human health and safety are jeopardized. In one case, an engineer learned that even a quiet resignation can prove very costly in a personal sense. Some ways in which professional societies might make ethical practice of engineering somewhat easier are mentioned. An carlier, shorter version of this paper was presented at the International Conference on Ethics in Engineering and Computer Science, Case Western Reserve University, Cleveland, March 21–24, 1999, and can be accessed on line at http://onlineethics.org/cases/unger.html. In all cases described in this paper, the names of individuals and organizations have been suppressed or fictionalized. Professor Unger was Chairman of the IEEE (Institute of Electrical and Electronics Engineers) Ethics Committee (1997–1998).     

Red-hot: How colour and semantic temperature processing interact in a Stroop-like paradigm

Temperature concepts and colour are commonly associated (i.e., red is “hot” and blue is “cold”), although their direction of influence (unidirectional, bidirectional) is unknown. Semantic Stroop effects, whereby words like fire influence colour categorization, suggest automatic semantic processing influences colour processing. The experiential framework of language comprehension indicates abstract concepts like temperature words simulate concrete experiences in their representation, where expressions like “red-hot” suggest colour processing influences conceptual processing. Participants categorized both colour (Experiment 1: red, blue; Experiment 2: red, green, blue) and word-meaning with matched lists of hot and cold meaning words in each colour. In Experiments 1 and 2, semantic categorization showed congruency effects across hot and cold words, while colour categorization showed facilitation only with hot words in Experiment 2. This asymmetry reflects a more consistent influence of colour categorization on semantic categorization than the reverse, suggesting experiential grounding effects may be more robust than the effects of semantic processing on colour processing.     

When words and space collide: Spatial attention interacts with lexical access during word recognition

Recent research has suggested an important role for spatial attention in reading, however the nature of this influence is unclear. Further, it has been shown that intention to engage in linguistic processing can enhance lexical processing. Therefore, we developed a novel paradigm to examine the impact of spatial attention on primed and unprimed lexical processing. In a lexical decision task, targets were preceded by a cue to lexical access and spatial location simultaneously. Results indicated that on spatially valid trials, the lexical cuing effect was large and word processing was enhanced, suggesting that spatial attention influences lexical access. On spatially invalid trials, lexical cuing effects were significantly decreased, resulting in a spatial cuing by lexical cuing interaction. Results from this experiment provide evidence that spatial attention interacts with lexical access during word processing. This novel paradigm provides a new avenue for exploring the relations between spatial attention and reading processes.     

Stressful life events and predictors of post-traumatic growth among high-risk early emerging adults

Stressful life events (SLEs) may elicit positive psychosocial change among youth, referred to as post-traumatic growth (PTG). We assessed types of SLEs experienced, degree to which participants reported PTG, and variables predicting PTG across 24 months among a sample of high-risk, ethnically diverse, early emerging adults. Participants were recruited from alternative high schools (n = 564; mean age = 16.8; 65% Hispanic). Multi-level regression models were constructed to examine the impact of environmental (SLE quantity, severity) and personal factors (hedonic ability, perceived stress, developmental stage, future time orientation) on a composite score of PTG. The majority of participants reported that positive changes resulted from their most life-altering SLE of the past two years. Predictors of PTG included fewer SLEs, less general stress, having a future time perspective, and greater identification with the developmental stage of emerging adulthood. Findings suggest intervention targets to foster positive adaptation among early emerging adults who experience frequent SLEs.     

The Role of Co-Occurrence Statistics in Developing Semantic Knowledge

The organization of our knowledge about the world into an interconnected network of concepts linked by relations profoundly impacts many facets of cognition, including attention, memory retrieval, reasoning, and learning. It is therefore crucial to understand how organized semantic representations are acquired. The present experiment investigated the contributions of readily observable environmental statistical regularities to semantic organization in childhood. Specifically, we investigated whether co-occurrence regularities with which entities or their labels more reliably occur together than with others (a) contribute to relations between concepts independently and (b) contribute to relations between concepts belonging to the same taxonomic category. Using child-directed speech corpora to estimate reliable co-occurrences between labels for familiar items, we constructed triads consisting of a target, a related distractor, and an unrelated distractor in which targets and related distractors consistently co-occurred (e.g., sock-foot), belonged to the same taxonomic category (e.g., sock-coat), or both (e.g., sock-shoe). We used an implicit, eye-gaze measure of relations between concepts based on the degree to which children (N = 72, age 4–7 years) looked at related versus unrelated distractors when asked to look for a target. The results indicated that co-occurrence both independently contributes to relations between concepts and contributes to relations between concepts belonging to the same taxonomic category. These findings suggest that sensitivity to the regularity with which different entities co-occur in children's environments shapes the organization of semantic knowledge during development. Implications for theoretical accounts and empirical investigations of semantic organization are discussed.     

A family member's job loss as a risk factor for smoking among adolescents.

Life events are associated with an increased likelihood of adolescent smoking. This study examined a family member's job loss as a predictor of smoking initiation over a 1-year period. Southern California students completed surveys in 6th and 7th grade. Of the 2,168 students, 252 (12%) reported that an adult in the household had lost a job within the past 6 months. Controlling for demographic, socioeconomic. educational, and parenting characteristics. 6th-grade never-smokers who reported a job loss were significantly more likely to have tried smoking by 7th grade and to have smoked in the past 30 days. Job loss for a household member is a risk factor for adolescents' involvement in problem behaviors such as smoking.