A new F-score gradient-based training rule for the linear model

Pattern Analysis and Applications - Delta rule is a standard, well-established approach to train perceptron recognition model. However, mean squared error, on which it is based, is not suitable...     

Silver content of wild-grown mushrooms from Northern Poland

Wild-grown and mostly edible species of higher mushrooms collected in 1989–1992 from the districts of Gdansk, Elblag and Pia (northern part of Poland) have been investigated with regard to their silver content. In total, 527 samples including 25 mushroom species of six families (Agaricaceae, Boletaceae, Cantharellaceae, Hygrophoraceae, Coprinaceae andRussulaceae) were examined. Among the fungi examined onlyAgaricus campestris andA. augustus were heavy bioaccumulating species and showed the highest concentrations of 35 mg Ag/kg dry weight (1.1–150) and 2.0–6.9 mg/kg, respectively. Silver concentrations exceeding 1.0 mg/kg dry weight were noted inBoletus aestivalis, Lepista nuda, L. personata, and in some specimens ofB. edulis, Leccinum scrabum, L. vulpinum, Cantharellus cibarius andCoprinus comatus.

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Silbergehalt in wildwachsenden Pilzen Nordpolens

Zusammenfassung Der Silbergehalt in wildwachsenden und vorwiegend eßbaren, auf dem Gebiet der Woiwodschaften Gdask, Elblag und Pia (Nordpolen) in den Jahren 1889–1992 gesammelten Pilzsorten wurde untersucht. Im ganzen wurden 527 Proben von 25 Arten der 6 Familien (Agaricaceae, Boletaceae, Cantharellaceae, Hygrophoraceae, Coprinaceae, Russuulaceae) zugehörenden Pilzen untersucht. Von diesen Pilzen waren nurAgaricus campestris undA. augustus stark bioanreichernde Arten mit höchsten Konzentrationen von 35 mg Ag/kg Trockenmasse (1.5–150) und 2.0–6.9 mg/kg. Eine Silberkonzentration von über 1.0 mg/kg Trockenmasse wurde inBoletus aestivalis, Lepista nuda, L. personata und in einigen Exemplaren vonB. edulis, Leccinum scrabum, L. vulpinum, Cantharellus cibarius undCoprinus comatus feststellt.

     

Influence of a photoinitiator on the photochemical stability of poly(methyl methacrylate) studied with fourier transform infrared spectroscopy

Fourier transform infrared (FTIR) spectroscopy was used to investigate the effect of a commercial photoinitiator [2,2‐dimethoxy‐2‐phenylacetophenone (DMPA); Irgacure 651, Ciba, Basel, Switzerland] incorporated into poly(methyl methacrylate) (PMMA). Pure PMMA and modified PMMA (containing 5% DMPA) films were exposed to a xenon lamp in air. Qualitative and quantitative analyses of the recorded FTIR absorption spectra were done. This allowed us to determine the differences in the course of polymer photooxidative degradation occurring in PMMA and PMMA doped with DMPA. We found that the initiator added to polymer film enhanced the efficiency of the formation of the photooxidized products containing functional groups of different types, which could be distinguished by mathematical treatment of the FTIR spectra. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Ultrasmall Co3O4 Nanocrystals Strongly Enhance Solar Water Splitting on Mesoporous Hematite

The synthesis of crystalline, nonagglomerated, and perfectly dispersible Co₃O₄ nanoparticles with an average size of 3–7 nm using a solvothermal reaction in tert‐butanol is reported. The very small size and high dispersibility of the Co₃O₄ nanoparticles allow for their homogeneous deposition on mesoporous hematite layers serving as the photoactive absorber in the light‐driven water splitting reaction. This surface treatment leads to a striking photocurrent increase. While the enhancement of hematite photoanode performance by cobalt oxides is known, the preformation and subsequent application of well‐defined cobalt oxide nanoparticles are novel and allow for the treatment of arbitrarily complex hematite morphologies. Photoelectrochemical and transient absorption spectroscopy studies show that this enhanced performance is due to the suppression of surface electron–hole recombination on time scales of milliseconds to seconds.     

A survey of research and studies on design

This review is based on two hundred responses to a questionnaire designed by the Design Methodology Unit, Department of Praxiology, Polish Academy of Sciences. On the basis of the replies it shows the state of research in design and the applied sciences.     

Effect of nanosilver on the photodegradation of poly(lactic acid)

The poly(lactic acid), PLA, mixed with nanosilver in solution easily forms nanocomposite in solid state (after solvent evaporation), which was proved by UV–Vis spectroscopy. This work focuses on photodegradation occurring in PLA films doped with nanosilver. The changes in chemical structure of photodegraded PLA has been determined using FTIR spectroscopy. Differential scanning calorimetry of UV‐irradiated PLA samples provided information on polymer glass transition and crystallization/melting processes. It was found that PLA alone is more sensitive to photodegradation than PLA/silver nanocomposites. The mechanism of nanocomposite photodegradation and effect of nanosilver was discussed. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40144.     

Magnetic Particles with Polymeric Shells Bearing Cholesterol Moieties Sensitize Breast Cancer Cells to Low Doses of Doxorubicin

One of the promising strategies for improvement of cancer treatment is application of a combination therapy. The aim of this study was to investigate the anticancer activity of nanoformulations containing doxorubicin and iron oxide particles covered with polymeric shells bearing cholesterol moieties. It was postulated that due to high affinity to cell membranes, particles comprising poly(cholesteryl acrylate) can sensitize cancer cells to doxorubicin chemotherapy. The performed analyses revealed that the developed systems are effective against the human breast cancer cell lines MCF-7 and MDA-MB-231 even at low doses of the active compound applied (0.5 µM). Additionally, high compatibility and lack of toxicity of the tested materials against human red blood cells, immune (monocytic THP-1) cells, and cardiomyocyte H9C2(2-1) cells was demonstrated. Synergistic effects observed upon administration of doxorubicin with polymer–iron oxide hybrids comprising poly(cholesteryl acrylate) may provide an opportunity to limit toxicity of the drug and to improve its therapeutic efficiency at the same time.     

The effect of germination process on the superoxide dismutase-like activity and thiamine,riboflavin and mineral contents of rapeseeds

Seeds of double low oilseed rape variety Mango (Brassica napus, var. oleifera) were subjected to a 7-day germination at 25 °C and 95% moisture content in darkness in a conditioning cabinet. The effects of the germination process on the superoxide dismutase-like activity (SOD-like activity), thiamine (vitamin B₁) and riboflavin (vitamin B₂) and minerals, such as Ca, Mg, Cu, Fe and Mn, were studied. Correlations between individual mineral contents, vitamin B₁ and B₂ contents, and the ability of phosphate buffered saline (PBS) extracts from germinated rapeseed to scavenge superoxide anion radicals in vitro were also investigated. SOD-like activity showed a gradual increase after the second day of germination, reaching a maximum level on the sixth day, and remained almost constant up to the end of the germination period. During germination, thiamine underwent a progressive decrease up to the sixth day, reaching a constant level between the sixth and the seventh day. In contrast, riboflavin content increased throughout the germination period up to the fifth day, and after that a constant level was observed. Levels of Ca and Mg were almost constant up to the fourth day and after that an increase of these minerals was observed. Cu and Mn increased during the germination process, and retentions of 33% and 22%, respectively, were observed at the end of germination. Fe content dropped after 1 day of germination and from there onward it started to increase gradually and an 18% retention was observed in 7-day germinated seeds. Positive correlations between SOD-like activity and riboflavin (r = 0.87), Cu (r = 0.74) and Mn (r = 0.87) were found during rapeseed germination.