Self-calming of a random network of dendritic neurons

A network of neurons with dendritic dynamics is analyzed in this paper. Two stable regimes of the complete network can coexist under continuous weak stimulation: the oscillatory synchronized regime and the quiet regime, where all neurons stop firing completely. It is shown that a single control pulse can calm a single neuron as well as the whole network, and the network stays in the quiet regime as long as the weak stimulation is turned on. It is also demonstrated that the same control technique can be effectively used to calm a random Erdös–Renyi network of dendritic neurons. Moreover, it appears that the random network of dendritic neurons can evolve into the quiet regime without applying any external pulse-based control techniques.     

Analysis of insect triacylglycerols using liquid chromatography‐atmospheric pressure chemical ionization‐mass spectrometry

An HPLC non‐aqueous reversed‐phase separation system was adapted for analyzing insect triacylglycerols (TAG). The method uses two conventional Nova‐Pak C18 columns connected in series, for a total length of 45 cm. The mobile phase gradient is mixed from acetonitrile and 2‐propanol, and the flow rate is programmed from 1.0 to 0.7 mL/min. TAG are detected by atmospheric pressure chemical ionization‐mass spectrometry. The method ensures efficient separation of isomers and analysis of high‐molecular‐weight TAG with equivalent chain lengths up to 72. The method performance is demonstrated on analysis of TAG isolated from the fat body of the bumblebee Bombus lucorum.     

Increase in buildings sustainability by using renewable materials and energy

Sustainable development could be seen as indispensable condition for survival of civilization. Construction sector is a field with immediate need for reducing environmental impacts. Sustainability measures applied for buildings could produce very efficient results to the people. The paper provides the methods of construction sustainability increase by researching, developing, and applying the technologies which use renewable materials and energy. The paper analyzes the cases of both a solar eco house which was built of original prefabricated straw-bale panels and was designed to use direct solar energy; and an educational project promoting straw-bale construction and seeking to mitigate climate change. The project results have shown the need of spreading information on sustainable building methods to be accepted by wider society and to be applied to the construction industry. Monitoring of solar ecohouse has proved that direct solar energy gains are significant in reducing heating degree-days in 55°N latitude and in allowing to save half the energy needed for heating.     

Interaction of polydiallyldimethylammonium salts with iodine

The interaction between polydiallyldimethylammonium chloride (PDADMAC) and KI or KBr, followed by changes in conformation of macromolecules, coil compaction, and counterion exchange, was detected by means of turbidimetry and viscometry. In aqueous solutions at presence of KI, PDADMAC rapidly binds iodine by the formation of polymer–iodine complexes PDADMA I^? I_m (m ≤ 4). Spectrophotometric investigations of the interaction in water without KI prove the formation of complexes of polyquaternary ammonium chloride or bromide with iodine only via iodide. These ions can be generated in the polymer‐catalyzed hydrolysis reaction of iodine. By inducing hydrolysis of iodine and binding the eventually formed iodide, PDADMAC acts as an iodine acceptor with self‐strengthening capacity. For the sorption of gaseous iodine, the possibility of direct interaction of its dipoles with the charged groups of the polyelectrolyte is also reasoned. Polydiallyldimethylammonium halides were used to modify activated carbon and employed in a nuclear power station for treatment of outlet gases containing radioactive iodine. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2710–2716, 2006     

Detection of Salmonella spp., Yersinia enterocolitica,Listeria monocytogenes and Campylobacter spp. by real‐time multiplex PCR using amplicon DNA melting analysis and probe‐based assay

Syto9 and probe‐based multiplex real‐time PCR assays for simultaneous detection of a group of foodborne pathogens (named SYLC group), targeting Salmonella spp. (invA gene), Yersinia enterocolitica (ystA gene), Listeria monocytogenes (hly gene) and Campylobacter spp. (rrna gene), have been developed. The Syto9 assay generates amplicon DNA melting curve with four peaks of 86.5 ± 0.5, 84 ± 0.5, 81.5 ± 0.5 and 90.5 ± 0.5 °C corresponding Salmonella spp., Y. enterocolitica, L. monocytogenes and Campylobacter spp. targets, respectively. The sensitivities of the Syto9 and TaqMan assays in artificially inoculated chicken wing rinses were in a range of 3.2 × 10² to 3.1 × 10⁴ and 9.8 × 10² to 1.9 × 10⁴ colony‐forming units per millilitre, respectively, depending on the pathogen. All tested target strains (n = 100) were correctly detected by the both assays, whereas nontarget strains (n = 100) demonstrated no cross‐reactivity representing 100% specificity. The assays are suitable for application in qualitative and quantitative detection of SYLC group pathogens in food matrices.     

Structural,morphological, and magnetic characterization of bulk and thin films Y3Al5–xFexO12 (YAIG): From the perspective of aqueous sol–gel processing

An aqueous sol–gel method was used for the preparation of bulk Y₃Al_5–xFe_xO₁₂ (yttrium aluminum–iron garnet, YAIG) with the composition of x?=?0.0, 1.0, 2.0, 2.5, 3.0, 4.0, 5.0 and thin films with the composition of x?=?0, 3.0, 4.0, 5.0. The dip-coating technique was used for the preparation of Y₃Al_5–xFe_xO₁₂ films on a silicon (Si) substrate. The phase composition and surface morphology of both bulk and coatings were determined and compared. The synthesized powder samples were investigated by X-ray diffraction analysis, infrared spectroscopy, scanning electron microscopy, and Mössbauer spectroscopy. The data provide evidence that some sol–gel-derived powder specimens consist of magnetically ordered component, while others show paramagnetic behavior depending on the composition of the product. It was also shown that sol–gel processing route could be successfully used for the preparation of mixed-metal YAIG thin films.     

Lignin Structural Changes During Liquefaction in Acidified Ethylene Glycol

Abstract

Beech (Fagus Sylvatica) milled-wood lignin was used as a model substrate in a study of lignin-catalyzed liquefaction in the presence of p-toluene sulfonic acid monohydrate (PTSA) or sulphuric acid as the catalysts. The structural changes that lignin undergoes during the treatment were studied by NMR spectroscopy, FTIR, size-exclusion chromatography, and high-performance liquid chromatography. For the sulphuric acid-catalyzed liquefaction, it was shown that the greater hydronium ion concentration in the reaction mixture induced formation of more condensed structures compared to the ones obtained after PTSA-catalyzed liquefaction. In addition, lignin during the PTSA-catalyzed liquefaction suffered degradation and was functionalized by the ethylene glycol. Gradual introduction of the ethylene glycol moieties into the lignin structure formed a condensed lignin-based polymeric material with predominant aromatic hydroxyl groups. HPLC and NMR analysis of the liquefied lignin with low-molecular mass fraction confirmed the presence of lignin monomers and further conversion of initially identified products into the aliphatic, aromatic (syringyl- and guaiacyl-based) esters and acids.