Characterization of activated sludge flocs by confocal laser scanning microscopy and image analysis

In this study we present a new approach to determine volumes, heterogeneity factors, and compositions of the bacterial population of activated sludge flocs by 3D confocal imaging. After staining the fresh flocs with fluorescein-isothiocyanate, 75 stacks of images (containing approx. 3000 flocs) were acquired with a confocal laser scanning microscope. The self-developed macro 3D volume and surface determination for the KS 400 software package combined the images of one stack to a 3D image and calculated the real floc volume and surface. We determined heterogeneity factors like the ratio of real floc surface to the surface of a sphere with the respective volume and the fractal dimension (D(f)). According to their significant influence on floc integrity and quality, we also investigated the chemical composition of flocs and quantified their bacterial population structure by using group-specific rRNA-targeted probes for fluorescence in situ hybridization. By a settling experiment we enriched flocs with poor settling properties and determined the above-mentioned parameters. This approach revealed shifts in floc volume, heterogeneity, and bacterial and chemical composition according to the settling quality of the flocs.     

Mercury levels in lichens from different host trees around a chlor-alkali plant in New Brunswick,Canada

Mercury concentrations were determined in the epiphytic lichen Hypogymnia physodes along five transects starting from a chlor-alkali plant located at Dalhousie, New Brunswick, a landfill site and a nearby electricity generating station. Lichen samples were collected from white birch (Betula papyrifera) and spruce (Picea sp.) or balsam fir (Abies balsamea). Average lichen background mercury values were 0.088+/-0.005 microg/g from white birch and 0.148+/-0.046 microg/g from spruce trees, with a detection limit of 0.05 microg/g. The chlor-alkali plant and a power plant were identified, respectively, as a major source and a minor source of elevated mercury levels in lichens. At 125 m north-west of the New Brunswick Power plant, 0.28 microg/g Hg were found in Hypogymnia physodes from spruce trees, while at 250 m west (downwind) of the chlor-alkali plant, 3.66 microg/g of mercury were determined. High values, 0.98 microg/g in lichens from spruce trees and 0.79 microg/g in lichen samples from white birch were also measured at 125 m south of the chlor-alkali plant and decreased exponentially with distance. The sphere of influence of the chlor-alkali plant with respect to mercury deposition was estimated to extend 2.4-3.4 km from the plant. The mercury concentrations in Hypogymnia physodes collected from white birch were significantly lower than the concentrations in the same lichen from spruce trees in areas with elevated levels of mercury, but not in areas with low mercury levels. The magnitude of this difference dropped with distance from the source.     

Predicting future clinical adjustment from treatment outcome and process variables.

General issues relating to the use of outcome and process data from the treatment of antisocial children to predict future childhood adjustment are examined. For outcome measures, it was assumed that variables based on direct observation of child behavior would provide a better predictor of long-term adjustment than would ratings by participant adults. Long-term adjustment measures consisted of police arrest and out-of-home placement data collected 2 years after treatment termination. Observation data collected at termination predicted future police arrest, but parent and teacher ratings did not. It was also hypothesized that measures of the processes thought to produce the changes in child antisocial behavior would serve as predictors of future adjustment. The data supported this hypothesis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Composition and antimalarial activity in vitro of volatile components of Lippia multiflora

The essential oil of Lippia multiflora was prepared by hydrodistillation of leaves and stalks and characterized by GC and mass spectroscopy. The oil was tested for antimalarial activity on in vitro cultures of Plasmodium falciparum (FcB1-Columbia chloroquine-resistant strain and F32-Tanzania chloroquine-sensitive strain). The dilutions inhibiting the in vitro growth of the parasite by 50% 24 and 72 hr after administration of the essential oil to the parasite culture were 1/12,000 and 1/21,000, respectively. When tested on a highly synchronized culture, the essential oil inhibited growth mostly at the trophozoite-schizont step, indicating a potential effect on the first nuclear division of the parasite.     

Picture cues and exhaustive search facilitate very young children's memory for location.

Conducted 3 experiments to examine the effects of picture cues and exhaustive search on very young children's memory for the location of hidden objects. In Exp I, 64 2-yr-olds' performance was examined with control and exhaustive search procedures in spatial-only and spatial- and picture-cue conditions. In Exp II, 32 2-yr-olds' performance with the same 2 search procedures was examined in a cue condition that eliminated spatial information. In Exp III, 64 2- and 3-yr-olds' performance with the control and exhaustive search procedures was examined in 2 array conditions that also eliminated spatial information. All experiments confirmed that even 2-yr-olds use picture cues to encode and search for the location of hidden objects. It was also found that while 2-yr-olds' delayed response performance was improved by exhaustive search procedures, this was not true for 3-yr-olds. Apparently, more complete search strategies contribute to the developmental change in young children's localization performance. (10 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Rules for neuropsychological diagnosis: Classification of brain function in older children.

A system of rules based on neuropsychological test data and the 2nd author's 4 methods of inference (level of performance, right–left differences, patterns of performance, and pathognomonic signs) was developed for classifying 3 samples (19 Ss each) of 9–14 yr old children as normal, learning disabled, or brain damaged. The 37 rules used a 4-point scaled scoring system with 0 representing adequate performance, 3 indicating distinctly abnormal performance, and 1 and 2 indicating intermediate performance. The rules system classified children into the 3 groups (normal, learning disabled, and brain damaged) with 73.3% accuracy. Although in need of replication, results indicate that the rules system is sensitive to neuropsychological differences between these groups and represents a set of initial guidelines for differentiating among normal, brain-damaged, and learning disabled children. Results also support the contention that learning disability often represents a degree of cerebral dysfunction that is frequently undetected by neurological examination but that can be reliably measured by neuropsychological tests. (9 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Some effects of testing methodology on children's cross-modal performance.

Tested 40 41-57 mo old children on the number of trials they took to learn the identical form-discrimination problem given in either visual or tactual modalities in either "held" (E gave S the reward) or "platform" (S himself picked up the reward) conditions. It appears that when testing methodology is equated in the 2 modalities, cross-modal transfer of a simple form discrimination is not asymmetrical, but rather is equivalent to the transfer from the tactual to the visual modality. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Pyrrole‐Assisted and Easy Oxidation of Cyclic α‐Amino Acid‐ Derived Diketopiperazines under Mild Conditions

A new procedure for the aerobic oxidation of α‐amino acids acylated by pyrrole‐carboxylic acid with triplet dioxygen is introduced. The reaction is general for a variety of pyrrole‐amino acid derivatives and represents a very practical and controllable method for the selective preparation of α‐hydroperoxy‐ or α‐hydroxy‐α‐amino acid diketopiperazines with molecular dioxygen. Furthermore, the non‐catalyzed direct oxidation of amino acid derivatives at the α‐position with molecular dioxygen represents a fundamental question.     

Bendability of advanced high strength steels—A new evaluation procedure

The significant lightweight engineering potential of advanced high strength steels (AHSS) is limited by its moderate formability and altered failure behavior compared to mild steel grades. Especially bendability is crucial in automotive applications. The failure phenomena and underlying damage mechanisms in small curvature bending of AHSS are revealed in this work. A new characterization approach based on optical strain measurement is presented to comprehensively identify the failure stages, critical strains and bending angles in a user-independent manner. The novel approach is generalized and broadly applicable. Thus it gives a prerequisite for improved and material specific industrial process design in future.