Airborne and dust borne microorganisms in selected Polish libraries and archives

The aims of this work were to quantitatively and qualitatively study culturable fungi and bacteria in the air and settled dust in the storerooms of five Polish libraries and archives as well as to estimate the effect of water intrusion on the microbial air quality indoors. In all studied storerooms, the total bioaerosol concentrations at the workplaces ranged from 100 to 1000 cfu/m³. The most prevalent part of the storerooms’ bioaerosol consisted of bacteria, mainly Staphylococcus spp. and Micrococcus spp., followed by filamentous fungi. In four of the studied premises, fungal aerosol concentrations were below 100 cfu/m³. The only exception was observed in the fifth storeroom, which has been periodically flooded with rainwater and where significantly higher concentrations of fungal aerosol were measured. Among the identified fungal species, those of the genus Penicillium were the most numerous. Moreover, Trichothecium laxicephalum and Alternaria tenuis were present in all of the examined storerooms.     

Perchlorate in raw and drinking water sources in England and Wales

A well‐known use of perchlorate is as a rocket fuel propellant; however, more widespread uses include in munitions and fireworks, and it also occurs naturally. Perchlorate suppresses the thyroid, which can lead to a variety of adverse effects. It is a widespread contaminant in the United States, but limited occurrence data in the United Kingdom exist, and even less for drinking water. Monitoring of 20 raw and treated drinking water sites in England and Wales, covering four seasonal periods, showed that perchlorate is a low‐level background contaminant of raw and treated drinking water. Low concentrations (treated drinking water: <0.020–2.073 μg/L, mean 0.747 μg/L) were detected at every higher‐risk site. The concentrations were comparable in each of the four sampling exercises and no significant trends were apparent relating to the time of year, the type of risk or the method of chlorination. Limited data showed that removal by ion exchange and granular‐activated carbon may occur.     

Antioxidant properties of extracts from Ginkgo biloba leaves in meatballs

The aim was to determine the effect of Ginkgo leaf extracts on the stability of lipids and cholesterol in pork meatballs over 21 days of refrigerated storage. The antioxidants used were characterized by their antioxidant activity towards lipids and cholesterol. Extracts were prepared from green and yellow leaves from Ginkgo biloba L. trees. Water, acetone and ethanol were used as extractants. The extracts showed stabilizing effects on both lipid and cholesterol oxidation processes. The lipid oxidation process of pork meatballs was mostly inhibited by the aqueous and ethanolic extracts of the yellow leaves. Their antioxidant activity was higher than that of BHT. All the extracts had a stabilizing effect on cholesterol and most of them inhibited the formation of oxidized derivatives. The acetone and ethanol extracts of green leaves and the ethanol extract of yellow leaves inhibited the formation of cholesterol oxidation products formation most effectively.     

Synthesis of N,N′‐Disulfonylamidines from Sulfonamides and Alkynes by a Two‐Step,One‐Pot Reaction with Nonafluorobutanesulfonyl Azide

Nonafluorobutanesulfonyl azide is an advantageous alternative to triflyl azide for the efficient synthesis of sulfonyl azides from sulfonamides in terms of its higher reactivity, lower cost, and non‐hazardous nature. The reagent has proven its utility in a novel synthesis of N,N′‐disulfonylamidines from available sulfonamides by a copper‐catalyzed two‐step, one‐pot sequential process with added terminal alkynes.     

AN EXPERIMENTAL STUDY OF THE PRESSURE DROP IN FLUID FLOWS THROUGH WIRE GAUZES

Catalytic wire gauzes have been used for many years for ammonia oxidation. The flow and transfer properties of stacked gauzes, however, have not been sufficiently examined in the literature. This study presents an experimental program designed to characterize the pressure drops observed across stacked woven and knitted wire gauzes. This work generated an extensive database of measurements and reveals that each gauze requires its own correlation equation. Furthermore, previously published general models were not able to describe all four cases with high accuracy. After surveying the literature, we present some modifications to the models based on our collected experimental results.     

Enhanced and Long‐Lived Near‐Infrared Luminescence of Er3+ Ions in Lead Borate Glass‐Ceramics Containing PbWO4 Nanocrystals

Lead tungstate PbWO₄ nanocrystals in transparent lead borate glass‐ceramics containing Er³⁺ ions were fabricated. Luminescence spectra at about 1530 nm due to main ⁴I_13/2–⁴I_15/2 laser transition of Er³⁺ ions were examined for glass samples before and after heat treatment. Near‐infrared luminescence of Er³⁺ ions in glass‐ceramics is enhanced and long‐lived in comparison to precursor glasses. It suggests that the Er³⁺ ions are partially incorporated into PbWO₄ crystalline phase.     

What visual information do children and adults consider while switching between tasks? Eye-tracking investigation of cognitive flexibility development.

This study investigated the visual information that children and adults consider while switching or maintaining object-matching rules. Eye movements of 5- and 6-year-old children and adults were collected with two versions of the Advanced Dimensional Change Card Sort, which requires switching between shape- and color-matching rules. In addition to a traditional integrated version with bidimensional objects (e.g., a blue bear), participants were tested on a dissociated version with pairs of unidimensional objects as stimuli (e.g., a noncolored bear beside a blue patch) so that fixations on the relevant and irrelevant dimensions of the stimuli could be distinguished. The fixation times were differentially distributed depending on whether children had to switch or maintain matching rules. Trial type differences in fixation times were primarily observed for the cues and the relevant and irrelevant dimensions of the stimuli, whereas responses options were seldom fixated even by the youngest children. In addition, the shape modality of the stimulus was more fixated than the color modality whether or not shape was relevant. Finally, the fixation patterns were modulated by age. These results suggest that switch costs are more related to selection of the relevant dimension on the stimulus than to response selection and point to age-related differences in strategies underlying flexible behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hierarchically porous phenolic resin-based carbons obtained by block copolymer-colloidal silica templating and post-synthesis activation with carbon dioxide and water vapor

A series of hierarchically porous carbons was synthesized by self-assembly of polymeric carbon precursors and block copolymer template in the presence of tetraethyl orthosilicate (TEOS) and colloidal silica under acidic conditions. Resorcinol and formaldehyde were used as carbon precursors, poly(ethylene oxide)–poly(propylene oxide)–poly(ethylene oxide) triblock copolymer was employed as a soft template, and TEOS-generated silica and colloidal silica were used as hard templates. The carbon precursors were polymerized in hydrophilic domains of block copolymer, followed by carbonization and silica dissolution. This resulted in carbons possessing cylindrical (∼12 nm) and spherical (20 or 50 nm) mesopores created by thermal decomposition of the soft template and by the dissolution of colloidal silica, respectively; fine pores were also formed by the dissolution of the TEOS-generated silica (∼2 nm). A further increase in fine porosity was achieved by post-synthesis activation of the carbons with carbon dioxide and/or water vapor, which resulted in hierarchical carbons with a surface area and pore volume approaching 2800 m²/g and 6.0 cm³/g, respectively.