Effects from log-yard stormwater runoff on the microalgae Scenedesmus subspicatus: intra-storm magnitude and variability

This paper describes the effects posed by stormwater runoff from an industrial log-yard on the microalgae Scenedesmus subspicatus. The effects of stormwater runoff sampled during two rain events were determined by exposing S. subspicatus cells to different concentrations (% v:v) of each sample. The effects were measured as the percentage change in growth rates in relation to a control culture after exposure times of 24, 48, 72 and 96 h. The runoff from the first rain event had no negative effects to S. subspicatus, posing in most cases growth stimulation, whereas the runoff from the second rain event inhibited algae growth. Differences in runoff physico-chemical characteristics combined with the hydrological factors of each rain event explained these opposite effects. The hypothesis of toxic first flush phenomenon was confirmed in the second rain event on the basis of normalized inhibitory effects and runoff volume. It was found that 42, 51 and 50% of the inhibitory effects during exposures of 24, 48 and 72 h were associated with the initial 4% of the total discharged volume. The fact that negative effects were observed in the two runoff events analyzed, raises concern about the potential environmental threats posed by runoff originated from wood-based industrial areas during the entire hydrological year.     

Nitrification of industrial and domestic saline wastewaters in moving bed biofilm reactor and sequencing batch reactor

Nitrification of saline wastewaters was investigated in bench-scale moving-bed biofilm reactors (MBBR). Wastewater from a chemical industry and domestic sewage, both treated by the activated sludge process, were fed to moving-bed reactors. The industrial wastewater contained 8000 mg Cl(-)/L and the salinity of the treated sewage was gradually increased until that level. Residual substances present in the treated industrial wastewater had a strong inhibitory effect on the nitrification process. Assays to determine inhibitory effects were performed with the industrial wastewater, which was submitted to ozonation and carbon adsorption pretreatments. The latter treatment was effective for dissolved organic carbon (DOC) removal and improved nitrification efficiency. Nitrification percentage of the treated domestic sewage was higher than 90% for all tested chloride concentrations up to 8000 mg/L. Results obtained in a sequencing batch reactor (SBR) were consistent with those attained in the MBBR systems, allowing tertiary nitrification and providing adequate conditions for adaptation of nitrifying microorganisms even under stressing and inhibitory conditions.     

Integrating natural language understanding with document structure analysis

Document understanding, the interpretation of a document from its image form, is a technology area which benefits greatly from the integration of natural language processing with image processing. We have developed a prototype of an Intelligent Document Understanding System (IDUS) which employs several technologies: image processing, optical character recognition, document structure analysis and text understanding in a cooperative fashion. This paper discusses those areas of research during development of IDUS where we have found the most benefit from the integration of natural language processing and image processing: document structure analysis, optical character recognition (OCR) correction, and text analysis. We also discuss two applications which are supported by IDUS: text retrieval and automatic generation of hypertext links     

Review of Existential—phenomenological perspectives in psychology.

Reviews the book, Existential — phenomenological perspectives in psychology edited by Ronald S. Valle and Steen Hailing (1989). This collection shows careful selection and editing by the two editors. Each of the articles is well-written, admirably clear, and articulate. The authors have succeeded in making the tenants of phenomenology accessible to those who do not have prior knowledge, however, the content is also of interest to people who are already familiar with the basics, but who wish to see phenomenological research in action. As such, the book could well serve as a text for an undergraduate or graduate level course entitled "existential-phenomenological perspectives in psychology", or as an adjunct text for a course which looks more broadly at various theoretical and methodological positions within the discipline. The editors have thoughtfully compiled the index with a view to the use of the book as a reference. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sensitivity loss and adaptation within the short-wavelength cone pathway

Two-color increment threshold data are used to develop a model of sensitivity control in short-wavelength detection. The model includes two sites of compressive nonlinearity. The first site has the characteristics of the S cones. Their output combines antagonistically with signals from the L and M cones at a second (blue/yellow opponent) stage. The response nonlinearities were examined by measuring thresholds for a 420-nm probe presented at the onset of flashed fields of 420-nm, 520-nm, and 580-nm light. Adaptive mechanisms of multiplication and subtraction were identified by presenting probe and flash on steady backgrounds of varying intensity. Adaptation partially restores the sensitivity lost to response compression.     

Characterization of highly hydrophobic coatings deposited onto pre-oxidized silicon from water dispersible organosilanes

The formation and quality of highly hydrophobic coatings deposited from water dispersible organosilanes onto pre-oxidized single crystal silicon were studied using atomic force microscopy, ellipsometry, dynamic contact angle measurements and electrochemical impedance spectroscopy (EIS). Highly hydrophobic films of a commercially available water dispersible silane and two different cationic alkoxysilanes were prepared by dip coating. It was found using atomic force microscopy that, in general, the structure of these highly hydrophobic films is a continuous film with some particulates attributed to bulk polymerization of the precursor molecule in water. Film defects were quantified using EIS by the value of charge transfer resistance at the hydrofluoric acid/silicon interface. Potential applications of this type of coatings include reduction/elimination of stiction in micro-electromechanical systems, contact printing in materials microfabrication, inhibition of corrosion and oxidation, prevention of water wetting, lubrication and protein adsorption.     

Theoretical and experimental studies of a bi-metallic heat switch for space applications

This work presents theoretical and experimental studies on a passively actuated bi-metallic heat switch for space applications. The working principle of the heat switch is based on the differential thermal expansion of distinct metals. Analytical one-dimensional and two-dimensional heat conduction models are developed to predict the thermal resistance of the heat switch, which is a function of temperature. A non-dimensional parametric analysis is performed in order to study how the design parameters affect the total thermal resistance of the heat switch. The theoretical models are also compared with experimental data obtained from a prototype of the heat switch. The agreement between theory and experiments is good.     

Windows on comprehension: Reading comprehension processes as revealed by two think-aloud procedures.

To address methodological questions regarding use of the think-aloud (TA) procedure and theoretical questions regarding the roles of prior knowledge and strategy use in reading comprehension, 24 college students each read 3 passages in 3 different presentation modes (marked TA, unmarked TA, and control) and answered essay comprehension questions. There was no effect of presentation mode on essay scores. TA comments were coded into 4 categories, 2 of which were significantly correlated with comprehension scores for marked but not unmarked passages. The authors conclude that the marked procedure elicited more veridical protocols. A second coding and analysis of the marked protocols showed that students who scored high on the comprehension test were more likely to have made many TA comments reflecting a "knowledge-transforming" approach to the text. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Signaturen durch elektronische Agenten

Elektronische Agenten können auf sämtlichen Stufen elektronischer Geschäftsprozesse eingesetzt werden, wodurch die Transaktionskosten gesenkt und der elektronische Geschäftsverkehr insgesamt beschleunigt und vereinfacht wird (vgl. [30], S. 548).