University of Houston

About: University of Houston is a education organization based out in Houston, Texas, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 23074 authors who have published 53903 publications receiving 1641968 citations.

The Nature of Phonological Awareness: Converging Evidence From Four Studies of Preschool and Early Grade School Children.

Abstract: Significant controversy exists about the nature of phonological awareness, a causal variable in reading acquisition. In 4 studies that included 202 5- to 6-year-old children studied longitudinally for 3 years, 123 2- to 5-year-old children, 38 4-year-old children studied longitudinally for 2 years, and 826 4- to 7-year-old children, the authors examined the relation of sensitivity to rhyme with other forms of phonological awareness. Rhyme sensitivity was indistinguishable from phonemic awareness, segmental awareness, and global phonological sensitivity in younger children. Rhyme sensitivity was distinguishable, although highly correlated, with these phonological skills in older children. Rhyme sensitivity was highly predictive of these other phonological skills. Children’s sensitivity to different linguistic units seems best conceptualized as a single underlying ability.

Detecting Stealthy False Data Injection Using Machine Learning in Smart Grid

Abstract: Aging power industries, together with the increase in demand from industrial and residential customers, are the main incentive for policy makers to define a road map to the next-generation power system called the smart grid. In the smart grid, the overall monitoring costs will be decreased, but at the same time, the risk of cyber attacks might be increased. Recently, a new type of attacks (called the stealth attack) has been introduced, which cannot be detected by the traditional bad data detection using state estimation. In this paper, we show how normal operations of power networks can be statistically distinguished from the case under stealthy attacks. We propose two machine-learning-based techniques for stealthy attack detection. The first method utilizes supervised learning over labeled data and trains a distributed support vector machine (SVM). The design of the distributed SVM is based on the alternating direction method of multipliers, which offers provable optimality and convergence rate. The second method requires no training data and detects the deviation in measurements. In both methods, principal component analysis is used to reduce the dimensionality of the data to be processed, which leads to lower computation complexities. The results of the proposed detection methods on IEEE standard test systems demonstrate the effectiveness of both schemes.

Marine peloids; a product of bacterially induced precipitation of calcite

Abstract: High-magnesian calcite peloids are a common constituent of cemented marine carbonate accumulations. They are abundant and well developed within both isolated microcavities and surface crusts. The nuclei of marine peloids are composed of fossil bacterial clumps encased within anhedral, submicron- to micron-sized, high-magnesian calcite crystals. The marine peloids are similar to silt-sized particles found in travertine deposits that also are composed of fossil bacterial clumps and their surrounding calcite coronas. These similarities include size (20-60 mu m), a cloudy brown nucleus, and rims of clear euhedral crystals. In addition, previous studies have established the presence of fatty acids of bacterial origin within peloidal deposits, and enriched stable isotopic signatures have been interpreted as recording organic fractionation concomitant with calcite precipitation. These characteristics all indicate that the nuclei of many peloids originate as calcite precipitates within and around clumps of bacteria and that this precipitation was induced by the vital activity of bacterial colonies.

Regulation of Drosophila life span by olfaction and food-derived odors

Abstract: Smell is an ancient sensory system present in organisms from bacteria to humans. In the nematode Caeonorhabditis elegans, gustatory and olfactory neurons regulate aging and longevity. Using the fruit fly, Drosophila melanogaster, we showed that exposure to nutrient-derived odorants can modulate life span and partially reverse the longevity-extending effects of dietary restriction. Furthermore, mutation of odorant receptor Or83b resulted in severe olfactory defects, altered adult metabolism, enhanced stress resistance, and extended life span. Our findings indicate that olfaction affects adult physiology and aging in Drosophila, possibly through the perceived availability of nutritional resources, and that olfactory regulation of life span is evolutionarily conserved.

Cardiorespiratory fitness, body composition, and all-cause and cardiovascular disease mortality in men.

Abstract: Background: Cardiorespiratory fitness and body fatness are both related to health, but their interrelation to all-cause and cardiovascular disease (CVD) mortality is unknown. Objective: We examined the health benefits of leanness and the hazards of obesity while simultaneously considering cardiorespiratory fitness. Design: This was an observational cohort study. We followed 21925 men, aged 30-83 y, who had a body-composition assessment and a maximal treadmill exercise test. There were 428 deaths (144 from CVD, 143 from cancer, and 141 from other causes) in an average of 8 y of follow-up (176742 man-years). Results: After adjustment for age, examination year, cigarette smoking, alcohol intake, and parental history of ischemic heart disease, unfit (low cardiorespiratory fitness as determined by maximal exercise testing), lean men had double the risk of all-cause mortality of fit, lean men (relative risk: 2.07: 95% Cl: 1.16, 3.69; P = 0.01). Unfit, lean men also had a higher risk of all-cause and CVD mortality than did men who were fit and obese. We observed similar results for fat and fat-free mass in relation to mortality. Unfit men had a higher risk of all-cause and CVD mortality than did fit men in all fat and fat-free mass categories. Similarly, unfit men with low waist girths (<87 cm) had greater risk of all-cause mortality than did fit men with high waist girths (≥99 cm). ). Conclusions: The health benefits of leanness are limited to fit men, and being fit may reduce the hazards of obesity.