RESUMO
The diversity of the bacterial community developed in different stages of two reverse osmosis (RO) water reclamation demonstration plants designed in a wastewater treatment plant (WWTP) in Tarragona (Spain) was characterized by applying 454-pyrosequencing of the 16S rRNA gene. The plants were fed by secondary treated effluent to a conventional pretreatment train prior to the two-pass RO system. Plants differed in the material used in the filtration process, which was sand in one demonstration plant and Scandinavian schists in the second plant. The results showed the presence of a highly diverse and complex community in the biofilms, mainly composed of members of the Betaproteobacteria and Bacteroidetes in all stages, with the presence of some typical wastewater bacteria, suggesting a feed water origin. Community similarities analyses revealed that samples clustered according to filter type, highlighting the critical influence of the biological supporting medium in biofilm community structure.
Assuntos
Bactérias/classificação , Biofilmes , Incrustação Biológica , Instalações de Eliminação de Resíduos , Purificação da Água/métodos , Bactérias/crescimento & desenvolvimento , Osmose , RNA Ribossômico 16S/genética , EspanhaRESUMO
OBJECTIVE: This study aimed at exploring the citation parameters of contact lenses articles published in the Ophthalmology thematic category of the Journal Citation Reports (JCR). METHODS: The Thompson Reuters Web of Science database was accessed to record bibliometric information and citation parameters of all journals listed under the Ophthalmology area of the 2011 JCR edition, including the journals with main publication interests in the contact lens field. In addition, the same database was used to unveil all contact lens-related articles published in 2011 in the same thematic area, whereupon differences in citation parameters between those articles published in contact lens and non-contact lens-related journals were explored. RESULTS: Significant differences in some bibliometric indicators such as half-life and overall citation count were found between contact lens-related journals (shorter half-life and fewer citations) and the median values for the Ophthalmology thematic area of the JCR. Visual examination of all Ophthalmology journals uncovered a total of 156 contact lens-related articles, published in 28 different journals, with 27 articles each for Contact Lens & Anterior Eye, Eye & Contact Lens, and Optometry and Vision Science. Significant differences in citation parameters were encountered between those articles published in contact lens and non-contact lens source journals. CONCLUSIONS: These findings, which disclosed contact lenses to be a fertile area of research, may be of interest to researchers and institutions. Differences in bibliometric indicators are of relevance to avoid unwanted bias when conducting between- and within-discipline comparisons of articles, journals, and researchers.
Assuntos
Lentes de Contato , Oftalmologia , Publicações Periódicas como Assunto , Bibliometria , HumanosRESUMO
Water recycling and reuse is of important value in water-using sectors like petrochemical industry. The aim of this research was to optimise the pre-treatment of petrochemical wastewater to undergo a further membrane treatment, with the final objective of water recycling within the same industry. Laboratory coagulation-flocculation tests prior to biological treatment were performed using Actiflo® Veolia commercial technology and an optimal coagulant dose of 30â¯mg/L ferric chloride was obtained. A bench-scale Moving Bed Biofilm Reactor (MBBR) system with two sequential reactors with working volumes of 5â¯L was filled with Z-carriers at 35% of their working volume. Organic loading rate (OLR) was varied from 0.2 to 3.25â¯kg/(m3 d) and the hydraulic retention time (HRT) ranged from 23.4â¯h to 4.5â¯h. High soluble chemical oxygen demand (sCOD) removals were obtained in stationary states (80-90%) and the calculated maximum sCOD that the system could degrade was 4.96⯱â¯0.01â¯kg/(m3 d) at 23⯱â¯2⯰C. Changes in feed composition did not decrease sCOD removals showing that MBBR is a robust technology and the coagulation-flocculation step could be by-passed. Further removal of total suspended solids (TSS) and turbidity from the MBBR effluent would be required before a reverse osmosis (RO) step could be performed. A biofilm-forming genus, Haliscomenobacter spp., and an oil degrading genus Flavobacterium spp. were found in all the attached biomass samples. Acinetobacter spp. was the major bacterial genera found in suspended biomass. Proteobacteria and Bacteroidetes were the major phyla detected in the carrier samples while Proteobacteria the main one detected in the suspended biomass. The lack of fungal annotated sequences in databases led to a major proportion of fungal sequences being categorized as unclassified Fungi. The results obtained indicate that MBBR is an appropriate technology for hydrocarbon-degrading microorganism growth and, thus, for petrochemical wastewater pre-treatment for water regeneration.
Assuntos
Biofilmes , Reatores Biológicos , Floculação , Eliminação de Resíduos Líquidos , Águas ResiduáriasRESUMO
PURPOSE: To determine the main current research interests of scientists working in the contact lens field. METHODS: All articles published in the 2011 issues of all journals included in the Journal Citation Reports subject category Ophthalmology were inspected to expose those papers related to the contact lens field. Information regarding source journal was obtained and authorship details were recorded to determine the top most prolific authors, institutions and countries. A comprehensive list of key words was compiled to generate a two-dimensional term map in which the frequency of occurrence of a particular term is defined by label size and the distance between two terms is an indication of the relatedness of these terms, based on their co-occurrences within groups of key words. Clusters of related terms were also identified. RESULTS: Visual examination of all articles uncovered a total of 156 papers, published in 28 different journals. Contact Lens & Anterior Eye, Eye & Contact Lens and Optometry and Vision Science had 27 articles each. The most prolific authors and institutions revealed the predominance of countries with long research tradition in the contact lens field. Ten different word clusters or areas of interest were identified, including both traditional, yet unresolved issues (e.g., comfort or dry eye), and the latest research efforts (e.g., myopia control). CONCLUSIONS: These findings, which revealed contact lenses to be a fertile area of research, may be of relevance to new researchers as well as to those interested in exploring the latest research trends in this scientific discipline.