MACROMOLECULAR AND AROMATIC CHARACTER INFLUENCE OF SBR ON THE RHEOLOGICAL PROPERTIES OF WELL CEMENT SLURRIES

Ensuring the rheological properties of the latex-based cement slurries in steam EOR is indispensable. Ca(OH)2 is produced after cement/water reaction and the macromolecules tend to disturb the hydration process, after the latex demulsification, by covering the cement particle. The free water decreases due to the high hydrophilicity of demulsified SBR, where final gel values increased up to 67%. The slump diameter was decreased exponentially by increasing the latex content limiting the workability. SBR-modified slurries presented a Pseudoplastic non-Newtonian flow behavior and the plastic viscosity decreases gradually, while the yield stress values registered a progressive increment by adding SBR till 10%

Comparing the Bacterial Diversity of Acute and Chronic Dental Root Canal Infections

This study performed barcoded multiplex pyrosequencing with a 454 FLX instrument to compare the microbiota of dental root canal infections associated with acute (symptomatic) or chronic (asymptomatic) apical periodontitis. Analysis of samples from 9 acute abscesses and 8 chronic infections yielded partial 16S rRNA gene sequences that were taxonomically classified into 916 bacterial species-level operational taxonomic units (OTUs) (at 3% divergence) belonging to 67 genera and 13 phyla. The most abundant phyla in acute infections were Firmicutes (52%), Fusobacteria (17%) and Bacteroidetes (13%), while in chronic infections the dominant were Firmicutes (59%), Bacteroidetes (14%) and Actinobacteria (10%). Members of Fusobacteria were much more prevalent in acute (89%) than in chronic cases (50%). The most abundant/prevalent genera in acute infections were Fusobacterium and Parvimonas. Twenty genera were exclusively detected in acute infections and 18 in chronic infections. Only 18% (n = 165) of the OTUs at 3% divergence were shared by acute and chronic infections. Diversity and richness estimators revealed that acute infections were significantly more diverse than chronic infections. Although a high interindividual variation in bacterial communities was observed, many samples tended to group together according to the type of infection (acute or chronic). This study is one of the most comprehensive in-deep comparisons of the microbiota associated with acute and chronic dental root canal infections and highlights the role of diverse polymicrobial communities as the unit of pathogenicity in acute infections. The overall diversity of endodontic infections as revealed by the pyrosequencing technique was much higher than previously reported for endodontic infections

O uso de lágrimas artificiais em pacientes com glaucoma: um estudo retrospectivo e comparativo

PURPOSE: To evaluate the need for artificial tears by glaucoma patients under topical hypotensive treatment and to identify risk factors associated with it. METHODS: The charts of 175 glaucoma patients under medical treatment and 175 age-matched controls were reviewed. Age, gender, use of artificial tears, number of glaucoma medications used, and duration of treatment were recorded. RESULTS: Significantly more glaucoma patients (n=92; 52.6%) used artificial tears compared to age-matched controls (n=31; 17.7%) (p<0.001). Significantly more females (n=81; 39%) than males (n=42; 28.9%) used artificial tears (p=0.036). When the whole population was analyzed, female gender (OR=1.63) and the presence of glaucoma (OR= 5.14) were risk factors for the use of artificial tears (p<0.05). When the glaucoma population was analyzed, female gender (OR=2.57), number of medications &gt;2 (OR=1.92), and duration of treatment &gt;5 years (OR=2.93) were risk factors for the use of artificial tears (p<0.05). CONCLUSIONS: Topical treatment with antiglaucoma medication is a risk factor for the use of artificial tears. Female gender and long-term treatment of glaucoma with two or more medications were aggravating factors for the need for artificial tears.OBJETIVO: Avaliar a necessidade do uso de lágrimas artificiais por pacientes com glaucoma recebendo tratamento medicamentoso e identificar fatores de risco associados ao seu uso. MÉTODOS: Os prontuários de 175 pacientes com glaucoma sob tratamento medicamentoso e de 175 controles pareados por idade foram revistos. Os seguintes dados foram registrados: idade, sexo, uso de lágrimas artificiais, número de medicações antiglaucomatosas e duração do tratamento do glaucoma. RESULTADOS: Um número significativamente maior de pacientes com glaucoma (n=92; 52,6%) usava lágrimas artificiais em relação ao grupo controle (n=31; 17,7%) (p<0,001). Um número significativamente maior de mulheres (n=81; 39%) usava lágrimas artificias em relação aos homens (n=42; 28,9%) (p=0,036). Quando a população foi analisada como um todo, sexo feminino (OR=1,63) e presença de glaucoma (OR=5,14) foram fatores de risco para o uso de lágrimas artificiais (p<0,05). Quando apenas a população de glaucomatosos foi analisada, número de medicações &gt;2 (OR=1,92) e duração do tratamento &gt;5 anos (OR=2,93) foram fatores de risco para o uso de lágrimas artificiais (p<0,05). CONCLUSÕES: O tratamento com colírios antiglaucomatosos é um fator de risco para o uso de lágrimas artificiais. Sexo feminino e tratamento a longo prazo com duas ou mais medicações são fatores de risco adicionais para o uso de lágrimas artificiais.6

Metaphor-related figurative language comprehension in clinical populations : a critical review

This paper aims to critically review current studies with respect to definitions, methods, and results on the comprehension of metaphor, metonymy, idioms, and proverbs under the following clinical conditions: aphasia, Alzheimer’s disease, autism, brain injuries, specific language impairment, and Williams Syndrome. A comprehensive search of experimental psycholinguistic research was conducted using EBSCOhost, PsychInfo, PUBMED, and Web of Science databases. Thirty-eight studies met the review inclusion criteria. Results point to deficits in figurative language comprehension in all conditions considered, lack of clear definitions of the phenomena investigated, and varied methods throughout the sample. Patients’ difficulties are attributed to multiple factors, such as a lack of Theory of Mind, executive dysfunctions, and poor semantic knowledge. The study of nonliteral aspects of language comprehension in clinical populations reveals a range of disparate impairments. There was no specific feature about metaphor-related phenomena identified that could, on its own, account for the difficulty some populations have to understand figurative language. Rather, metaphor-related language comprehension difficulties are often part of pragmatic, linguistic, and/or cognitive impairments

In vitro screening by phototoxic properties of Eugenia uniflora L., Momordica charantia L., Mentha arvensis L. and Turnera ulmifolia L.

Ethanol extracts of Mentha arvensis L., Momordica charantia L., Turnera ulmifolia L. and Eugenia uniflora L. were screened for light – activated antibacterial activity against strains of Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. Triplicate assays were conducted with and without exposure to UV-A radiation to test for light-activated or light-enhanced activity. Only the ethanol extract of E. uniflora and M. charantia showed antibacterial activity against an E. coli strain when exposed to UV-A light. The results represent a first report of the light-mediated antimicrobial activity of E. uniflora and M. charantia and suggest that phytochemical investigations may be warranted.Extratos etanólicos de Mentha arvensis L., Momordica Charantia L., Turnera ulmifolia L. e Eugenia uniflora L. foram avaliados quanto a sua atividade antibacteriana ativada pela luz contra linhagens de Staphylococcus aureus, Escherichia coli e Pseudomonas aeruginosa. Experimentos em triplicata foram conduzidos com e sem exposição à radiação UV-A para verificar a presença de atividade antibacteriana ativada ou aumentada pela luz. Apenas os extratos etanólicos de E. uniflora e M. charantia apresentaram atividade contra uma linhagem de E. coli quando exposta à luz UV-A . Os resultados representam o primeiro relato de atividade antimicrobiana mediada pela luz de E. uniflora e M. charantia.Palavras-chave

Seasonal Botanical Composition and Available Forage of Natural Grasslands in the Southeastern Range Region of Rio Grande Do Sul, Brazil

The objective of the study was to verify the influence of climatic seasons on botanical composition and on available dry matter of grasslands in the physiographic region known as Serra do Sudeste (Southeastern Range), RS, Brazil. The climate is Cfb according to Koëppen`s classification. The experiment was conducted in two natural grasslands submitted to two pre-experimental stocking rates [area 1: 0.65 AU ha-1 (normal grazing); area 2: over 2.0 AU ha-1 (overgrazing); AU: Animal Unit = 500kg live weight]. Stocking rates throughout the experimental period (June 1996–July 1997) were 0.4 and 0.65 AU ha-1, over winter and the other seasons, respectively. The evaluations were made at the end of each season, using the Botanal package. There was a short forage supply over late autumn/early winter. The two species groupings warm-season grasses (70–78% of total dry matter) and broad leaves (18– 24%) were the main components of the vegetation in the lower layer of the two grasslands. Warm-season grasses had their participation slightly increased during the warmer seasons. The pre-experimental overgrazing of area 2 favoured the contribution of the minor groups cool-season grasses, warm-season legumes and cool-season legumes