Dehalogenation of polychlorinated biphenyls and polybrominated diphenyl ethers using a hybrid bioinorganic catalyst

The environmentally prevalent polybrominated diphenyl ether (PBDE) #47 and polychlorinated biphenyls (PCBs) #28 and #118 were challenged for 24 hours with a novel biomass-supported Pd catalyst (Bio-Pd(0)). Analysis of the products via GC-MS revealed the Bio-Pd(0) to cause the challenged compounds to undergo stepwise dehalogenation with preferential loss of the least sterically hindered halogen atom. A mass balance for PCB #28 showed that it is degraded to three dichlorobiphenyls (33.9%), two monochlorobiphenyls (12%), and biphenyl (30.7%). The remaining mass was starting material. In contrast, while PCB #118 underwent degradation to yield five tetra- and five trichlorinated biphenyls, no less chlorinated products or biphenyl were detected, and the total mass of degraded products was 0.3%. Although the Bio-Pd(0) material was developed for treatment of PCBs, a mass balance for PBDE #47 showed that the biocatalyst could prove a potentially useful method for treatment of PBDEs. Specifically, 10% of PBDE #47 was converted to identifiable lower brominated congeners, predominantly the tribrominated PBDE #17 and the dibrominated PBDE #4, 75% remained intact, while 15% of the starting mass was unaccounted for.     

Queen number, queen cycling and queen loss: the evolution of complex multiple queen societies in the social wasp genus Ropalidia

Complex, highly integrated societies have evolved from simpler societies repeatedly, and the social insects provide an excellent model system for understanding increasing complexity and integration. In the paper wasps, large societies, known as swarm-founding, have evolved repeatedly from smaller societies, known as independent-founding. Swarm-founding colonies have many more queens than independent-founding colonies, which should dramatically reduce relatedness, posing a challenge to cooperation. However, in each instance, swarm-founding species have also evolved a cyclical pattern of queen reduction which elevates relatedness despite high queen numbers. The genus Ropalidia provides an excellent system in which to study the transition to swarm-founding because it has both independent and swarm-founding species. We studied the Australian independent-founding wasp Ropalidia revolutionalis to better understand the evolution of multiple queens and their periodic reductions in swarm-founding wasps. Using microsatellite genetic markers we genotyped queens, workers and brood from 37 colonies and found that while most colonies had a single queen, three of the colonies had multiple queens at or immediately prior to the time of collection. An additional seven colonies had had multiple co-occurring queens earlier in the season. We also found that colonies experienced many queen losses, and that founding queens were gradually lost until they were replaced by a new cohort of daughter queens in many colonies. This pattern is similar to the periodic reductions and replacements in swarm-founding wasps and suggests that multiple queens and queen cycling evolved relatively early in the shift to swarm-founding in Ropalidia.Communicated by R. Page     

Scenes from a restaurant: Privacy regulation in stressful situations

Stress results when an individual has less control over an environment or a situation than is desired. One way of regaining control and reducing stress is to regulate privacy by screening the self from spatial, visual or acoustical invasion. This study examined the use of architectural features to regulate privacy under hypothetical situations that are likely to generate low, moderate and high stress, comparing the seating choices of males and females in a variety of dining scenarios in a restaurant. In more stressful circumstances such as those associated with a job interview, participants chose restaurant seating bounded by more architectural features than they did in more relaxed dining situations such as dining with friends. Males and females appeared to be different in their responses to moderate and high stress situations. These results have implications for designers of secondary settings where stressful interactions are likely to take place.     

Removal of Hg2+ ions by adsorption using (TiO2@MnO2)-NPs nanocomposite

Journal of Material Cycles and Waste Management - Waste water contaminated with inorganic mercury is considered a serious environmental problem, mainly due to the hazardous effects this contaminant...     

Competing probabilistic models for catch-effort relationships in wildlife censuses

Two probabilistic models are presented for describing the chance that an animal is captured during a wildlife census, as a function of trapping effort. The models in turn are used to propose relationships between sampling intensity and catch-per-unit-effort (C.P.U.E.) that were field tested on small mammal populations. Capture data suggests a model of diminishing C.P.U.E. with increasing levels of trapping intensity. The catch-effort model is used to illustrate optimization procedures in the design of mark-recapture experiments for censusing wild populations.     

A knowledge network to promote the use and valorization of wild food plants in the Pantanal and Cerrado,Brazil

Regional Environmental Change - The conservation and use of wild food plants should include local people in the decision-making process, and many countries have done so. However, interacting with...     

LED irradiated photo-Fenton for the removal of estrogenic activity and endocrine disruptors from wastewater treatment plant effluent

Environmental Science and Pollution Research - The goal of this work was to evaluate the performance of the LED irradiated photo-Fenton process on the removal of (i) estrogenic activity and (ii)...     

Protective effect of gamma-oryzanol against manganese-induced toxicity in Drosophila melanogaster

Environmental Science and Pollution Research - Manganese (Mn) is an essential element that, in excess, seems to be involved in the development of different neurodegenerative conditions....     

An HPLC method development for the assessment of degradation products of anthraquinone dye

The behavior of metsulfuron-methyl and its residues in an artificial pond was studied using a ¹⁴C isotopic tracer technique. Throughout the experimental period, the majority of metsulfuron-methyl residues were sustained in the pond water. Furthermore, the metsulfuron-methyl residues were just found in the surface layer of the sediment, and the transfer distance of these residues had only reached 9?C12 cm by the end of the experiment. The extract residues of metsulfuron-methyl in sediment were slightly higher than those of the bound residues (BR) during the initial experiment stage, while the BR dominated the surface sediment after 45 days. Finally, the metsulfuron-methyl residues could be combined with humus in the surface sediment, and the distribution of metsulfuron-methyl residues in fulvic acid was significantly higher than that in humic acid.