Carnivore fecal chemicals suppress feeding by Alpine goats (Capra hircus)

The efficacy of carnivore and ungulate fecal chemicals in suppressing the feeding behavior of Alpine goats (Capra hircus) was examined. In the first four experiments, goats were offered food covered with paper strips treated with fecal extracts of the Bengal tiger, Siberian tiger, African lion, and brown bear, respectively; food covered with solvent-treated and untreated (plain) papers served as controls in each experiment. Goats made fewer head entries into, and ate less food from, buckets containing fecal extracts. In the fifth experiment, goats were offered food covered with paper strips treated with fecal extracts of the puma, Dorcas gazelle, white-bearded gnu, and conspecifics; food covered with solvent-treated and plain papers again served as controls. The amounts of food consumed from buckets containing puma, gazelle, gnu, and solvent treatments were statistically indistinguishable, but less food was consumed from them than from buckets containing the goat-scented or plain papers. No significant differences among treatments were detected with respect to head entries. Field experiments are needed on the use of predator-derived chemicals to reduce damage by goats to vegetation.     

Precursor system of liquid crystalline phase containing propolis microparticles for the treatment of periodontal disease: development and characterization

Precursor systems of liquid crystalline phase were prepared using the surfactant PPG-5-Ceteth-20, isopropyl myristate, and water; gelatin microparticles containing propolis were then added into these systems. Homogeneity of dispersion, the in-system microparticle morphology, and sedimentation behavior of each formulation were evaluated. The rheological and mechanical properties (hardness, compressibility, and adhesiveness), the work of syringing, and the propolis release profile were also evaluated. All the formulations exhibited pseudoplastic flow and thixotropy, and they displayed storage modulus, loss modulus, dynamic viscosity, and loss tangent that depended on temperature, frequency, and composition. Mechanical properties varied significantly among the formulations being affected by changes in the composition and temperature. Raising the concentration of surfactant and adding propolis microparticles significantly decreased the work of syringing. The drug release was non-Fickian (anomalous) and there was no significant difference between the tested systems in the times required for 10%, 30%, and 50% release of the initial drug loading.     

Sulphur poisoning of palladium catalysts used for methane combustion: effect of the support

Four different supported palladium catalysts (using alumina, silica, zirconia and titania as supports), prepared by incipient wetness impregnation, were tested as catalysts for methane oxidation in presence of sulphur dioxide. The catalyst supported on zirconia showed the best performance, whereas the silica-supported one showed the fastest deactivation. Temperature-programmed desorption experiments of the poisoned catalysts suggest that SO(2) adsorption capacity of the support plays a key role in the catalyst poisoning. In order to study the effect of promoters, expected to improve the thermal stability and thioresistance of the catalyst, commercial zirconia modified by yttrium and lantane was tested as supports. It was found that the presence of these promoters does not improve the performance of the zirconia-supported catalyst. A deactivation model -- considering two different active sites (fresh and poisoning), pseudo-first order dependence on methane concentration and poisoning rate depending on sulphur concentration and fraction of non-poisoned palladium -- was used for modelling the deactivation behaviour.     

Developing Smart Grids Based on GPRS and ZigBee Technologies Using Queueing Modeling–Based Optimization Algorithm

Smart metering systems have become widespread around the world. RF mesh communication systems have contributed to the creation of smarter and more reliable power systems. This paper presents an algorithm for positioning GPRS concentrators to attain delay constraints for a ZigBee‐based mesh network. The proposed algorithm determines the number and placement of concentrators using integer linear programming and a queueing model for the given mesh network. The solutions given by the proposed algorithm are validated by verifying the communication network performance through simulations.     

Premature graduation of children in child restraint systems: an observational study

This study investigated the use and misuse of child restraint systems (CRS) in Flanders (Belgium). Observations were conducted at a random sample of primary school and recreation areas. In total 1376 children were observed. A logistic regression model was constructed in order to determine the variables involved. The parameter-estimates of this model have shown that children are more often restrained when the driver buckles up, the ride takes less than 1h, the children are younger, the children sit in the front seat of the car, a recreational area is the destination of the trip and there are less than five children in the car. Also premature graduation to CRS was analysed. More than half of the children are not appropriately restrained, according to their age, weight or height. Improper shoulder belt use (putting the shoulder belt behind the back or under the arm) was observed in 8.99% of the children being restrained with high back booster seats, in 32.73% of the children being restrained with backless booster seats and finally in 19.07% of the children being restrained with seat belts. The risk of incorrectly using the shoulder belt increases when children are prematurely graduated in a CRS. The results are discussed in the light of other studies on this matter.     

Electron Holes in G-Quadruplexes: The Role of Adenine Ending Groups

The study deals with four-stranded DNA structures (G-Quadruplexes), known to undergo ionization upon direct absorption of low-energy UV photons. Combining quantum chemistry calculations and time-resolved absorption spectroscopy with 266 nm excitation, it focuses on the electron holes generated in tetramolecular systems with adenine groups at the ends. Our computations show that the electron hole is placed in a single guanine site, whose location depends on the position of the adenines at the 3′ or 5′ ends. This position also affects significantly the electronic absorption spectrum of (G⁺)^● radical cations. Their decay is highly anisotropic, composed of a fast process (<2 µs), followed by a slower one occurring in ~20 µs. On the one hand, they undergo deprotonation to (G-H2)^● radicals and, on the other, they give rise to a reaction product absorbing in the 300–500 nm spectral domain.     

Preparation and thermal behavior of random poly(butylene terephthalate/azelate) copolyesters

Poly(butylene terephthalate), poly(butylene azelate), and poly(butylene terephthalate/butylene azelate) random copolymers of various compositions were synthesized in bulk using the well‐known two‐stage polycondensation procedure, and characterized in terms of chemical structure and molecular weight. The thermal behavior was examined by thermogravimetric analysis and differential scanning calorimetry. As far as the thermal stability is concerned, it was found to be rather similar for all copolymers and homopolymers investigated. All the copolymers were found to be partially crystalline, and the main effect of copolymerization was a lowering in the amount of crystallinity and a decrease of melting temperature with respect to pure homopolymers. Flory's equation was found to describe the T_m–composition data and permitted to calculate the melting temperatures (T^°_m ) and the heats of fusion (ΔH_u) of both the completely crystalline homopolymers. Owing to the high crystallization rate, the glass transition was observable only for the copolymers containing from 30 to 70 mol % of the terephthalate units; even though the samples cannot be frozen in a completely amorphous state, the data obtained confirmed that the introduction of the aromatic units gave rise to an increase of T_g, due to a chain stiffening. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 2694–2702, 1999     

Vitamins in brewing: presence and influence of thiamine and riboflavin on wort fermentation

Thiamine and riboflavin vitamers are present in a wide range of foods including beer. These vitamers play critical roles in a variety of enzymatic complexes and can promote and maintain metabolism. Currently, the presence and role of these vitamers in the malting and brewing industry have not been widely explored. This research investigated the effects of various fermentation conditions that may lead to the variations in the vitamin content in beer observed by previous researchers. The present research found that during fermentation, the thiamine content of wort is quickly utilized within the first 6 h of a standard fermentation and the uptake of this vitamin is not affected by increases in wort gravity. While no significant changes were observed in extracellular phosphorylated vitamers of thiamine, both free thiamine and thiamine diphosphate accumulated intracellularly during the wort fermentation. Meanwhile extracellular riboflavin vitamers were only poorly utilized during beer fermentations, however flavin mononucleotide rapidly accumulated intracellularly and more so under aerobic conditions. When yeast was exposed to an all‐malt high‐gravity wort, the thiamine or riboflavin utilization was not affected. However, thiamine utilization was reduced in adjunct‐driven high‐gravity worts. Notwithstanding the lowered thiamine uptake under high‐gravity conditions; there were some minor improvements in fermentation performance and yeast viability. The addition of thiamine to an all‐malt wort did appear to enhance yeast viability, both under normal and high‐gravity conditions. Copyright © 2016 The Institute of Brewing & Distilling