Enhancing nitrification in vertical flow constructed wetland utilizing a passive air pump

Nitrification of simulated secondary effluent solution using a variant of the vertical flow bed constructed wetland was studied. In this system oxygen required for the nitrification process is supplied by a passive air pump. The passive air pump is based on a fill and draw cycle, where oxygen depleted air is removed from the system while fresh air is introduced. Each volume of effluent drained is displaced by an equal volume of fresh air. Spatial and temporal oxygen distribution in the system as a function of drained effluent volume was investigated. Experimental results of nitrification and the corresponding oxygen consumption show good agreement with theoretical calculations based on physico–chemical considerations. Observations show that while oxygen distribution within the media was found to be non-uniform at the beginning of each cycle, it approached more uniform distribution with time. The latter resulted mainly from diffusion of oxygen in the gaseous phase.     

Filial therapy with Chinese parents: Effects on parental empathic interactons, parental acceptance of child and parental stress.

Determined the effectiveness of a 10-wk filial therapy training model as an intervention method for Chinese parents living in the US. Results of the analyses of covariance reveal that the Chinese parents in the experimental group had a significant increase in their level of empathic interactions with their children; a significant increase in their attitude of acceptance toward their children; and a significant reduction in their level of stress related to parenting. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mechanical properties and microstructure of boron-alloyed steel 19 MnB 4

Microalloying elements are useful to achieve maximum improvements of the mechanical properties in boron alloyed steels supposedly because they form precipitates with nitrogen and carbon to protect boron from precipitation. On the other hand, they are most useful for austenitic grain refinement and for the generation of the required minimum austenitic grain size (MAGS). A second heat treatment (700°C 9h/air) before quenching the Jominy samples is only efficient in a certain range of austenitic grain size. No increase of hardenability is observed above a certain plateau austenitic grain size (PAGS) for each steel group. A minimum austenitic grain size (MAGS) is required to achieve maximum strength. Boron can only improve the hardenability and tensile properties, if the austenitic grain size before martensitic transformation is optimal. Titanium appears to be the most effective element to prevent boron precipitation. The hardenability, yield and impact strength of the steel group B–AI–Ti is good, especially for sample 44.     

Ambulatory blood pressure and heart rate in healthy male paramedics during a workday and a nonworkday.

[Correction Notice: An erratum for this article was reported in Vol 11(3) of Health Psychology (see record 2008-10739-001). On page 52, the sentence "For example, the paramedics stood 16.44 times more while home than while at the station" should read "For example, the paramedics stood more while home than while at the station."] Compared ambulatory blood pressure (BP) and heart rate (HR) in 30 White male paramedics (aged 20–43 yrs) during a 24-hr workday and a 24-hr nonworkday. During the 24-hr period as a whole, there were no BP differences between the workday and the nonworkday, but HR was higher during the nonworkday than during the workday. Systolic BP (SBP) recorded in the ambulance on the workday was elevated 9.8 mm Hg, compared with SBP recorded in a car on the nonworkday; it was also 7.2 mm Hg higher at the scene of an accident and at the hospital than during nonworkday activities. Ratings of moods in diaries indicated that paramedics felt more unhappiness, stress, and sadness and less feelings of pleasantness at work than at home. Rather than being elevated for the entire 24-hr period, work BP seemed to reflect the relatively high stress associated with specific situations in the work of a paramedic. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A rose is a REEZ: The two-cycles model of phonology assembly in reading English.

The authors propose a model of phonological assembly that postulates a multilinear representation that segregates consonants and vowels in different planes. This representation determines the online process of assembly: Consonants and vowels are derived in 2 consecutive cycles that differ in their automaticity. The model's temporal properties resolve critical contradictions in the phonological processing literature. Its claims are further supported by a series of English-masking and English-priming experiments demonstrating that the contributions of consonants and vowels depend on target exposure duration and differ in their susceptibility to digit load. One methodological implication of the model is that regularity effects are not necessary evidence for assembly. This claim is supported by naming studies showing that vowel assembly requires long target durations, but short target durations permit consonant assembly despite null evidence for vowels. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Deviation of residual stress patterns in 52 100 bearing steel due to inherent microstructural transformations after rolling contact

A previous publication proved empirically that residual stresses in 52 100 bearing steel are caused mainly by microstructural transformations during rolling contact. It also introduced a model estimating the magnitude of residual stresses resulting from microstructural transformations. The results from this model prompted this study because the model showed a discrepancy between the measured results and the magnitude of the estimated residual stresses derived from the model. This study uses metallurgical analysis and modeling to explain why the measured and estimated magnitudes of residual stresses did not coincide. Metallurgical analysis explains the roles of retained austenite transformation and martensite decay in the ultimate magnitude of residual stresses at the surface of the bearing balls after rolling contact. The model estimates the magnitude of expected residual stresses due to martensite decay and suggests the number of cycles that bearing balls can operate under the beneficial effects of compressive residual stresses without spalling.     

Biobehavioral perspectives on hypertension.

The variables that influence blood pressure (BP) and hypertension include family history, personality, and stress (natural disasters, culture and urbanization, occupational stress, prolonged illness, experimentally induced stress, response to stress in individuals with a family history of hypertension, and Type A behavior). Other factors such as obesity, physical activity, dietary sodium, caffeine, and alcohol, are also noted. The major nonpharmacologic approaches to treatment of hypertension involve modification of physical risk factors (sodium restriction, weight loss, reduced caffeine and alcohol, physical training, drug adherence) and behavioral treatment methods (direct regulation of BP with biofeedback, regulation of sympathetic nervous activity, relaxation, and stress management). These methods are appraised, and suggestions are offered on improving the quality of treatment research in selection of patients and initial assessments, BP assessment, maintenance and follow-up, and generalization of treatment effects. (127 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Role of muscle tension in personality theory.

The relationship of muscle tension to personality is reviewed through the 19th century to the present. Although the methods of measurement are often only indirectly related to one another certain trends emerge. Skeletal muscle tension tends to be high: in the hyperactive person during emotional stress, in psychotic and neurotic groups, and particularly in disorders in which anxiety is the major concomitant. The mechanism of symptom specificity, whereby a particular muscle develops symptoms due to its constant state of sustained contraction, is also discussed. (3 p. ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

X-ray absorption near-edge structure analysis of arsenic species for application to biological environmental samples

Arsenic is an element that is ubiquitous in the environment and is known to form compounds with toxic, even carcinogenic properties. Arsenic toxicity is a function of its chemical form (species). Identification of arsenic species is necessary to accurately determine the transformation and fate of arsenicals as well as the actual risk posed by arsenic contamination. We report X-ray absorption near-edge structure (XANES) measurements of 16 biologically important arsenic compounds. Solid and aqueous standards were studied for differences in XANES spectral features, white line positions, stability during exposure to the beam, and stability between two beam exposures separated by 48 h. Samples containing As(III) (11870.0-11871.7+/-0.5 eV) and As(V) (11872.6-11875.3+/-0.5 eV) were easily distinguished by white line energies and could be further subdivided into a total of seven groups. Valuable examples include As(III)-sulfur compounds (11870.0+/-0.5 eV), arsenobetaine and arsenocholine (11872.6+/-0.5 eV), and a dimethyl arsinyl riboside (11873.3+/-0.5 eV). A growing number of environmental and biological studies use X-ray absorption spectroscopy (XAS) results to complement their more traditional analyses. Results provided here are intended to help make XAS more accessible to new users interested in the study of arsenic in the environment.     

Untersuchungen des Trauben- und Weinaromas

The free aroma compounds of wines were isolated by liquid-liquid extraction with a mixture of trichlorofluoromethane/dichloromethane whereas the enrichment of glycosidically bound aroma components was carried out by adsorption on XAD and subsequent elution with various solvents. The glycosidic compounds were liberated enzymatically byβ-glucosidases. The extracts were analysed by gas chromatography. In 92 wines of the varieties Riesling, Weißburgunder, Silvaner and Ruländer of three vintages (1989, 1990, 1991), from different regions and wine producers 160 free aroma compounds were quantitatively determined. By use of statistical analysis the components were reduced to 23 significant aroma constituents. Analytical characterization of the investigated grape varieties was possible with these components. Terpene compounds, unsaturated C₆-alcohols and some components of the amino acid metabolism were especially typical for the varietal character. Using 18 glycosidically bound aroma substances it could be shown that these components can also contribute significantly to the characterization of grape varieties where monoterpenes and norisoprenoids play an important role. Computing at the same time free and glycosidically bound aroma components in discriminant analysis the characterization of neutral grape varieties (Silvaner, Ruländer, Weissburgunder) can be considerably improved.