Thin-layer agar for detection of resistance to rifampicin, ofloxacin and kanamycin in Mycobacterium tuberculosis isolates

BACKGROUND: In low-income countries there is a great need for economical methods for testing the susceptibility of Mycobacterium tuberculosis to antibiotics. OBJECTIVE: To evaluate the thin-layer agar (TLA) for rapid detection of resistance to rifampicin (RMP), ofloxacin (OFX) and kanamycin (KM) in M. tuberculosis clinical isolates and to determine the sensitivity, specificity and time to positivity compared to the gold standard method. METHODS: One hundred and forty-seven clinical isolates of M. tuberculosis were studied. For the TLA method, a quadrant Petri plate containing 7H11 agar with RMP, OFX and KM was used. Results were compared to the Bactec MGIT960 for RMP and the proportion method for OFX and KM. RESULTS: The sensitivity and specificity for RMP and OFX were 100% and for KM they were 100% and 98.7%, respectively. The use of a TLA quadrant plate enables the rapid detection of resistance to the three anti-tuberculosis drugs RMP, OFX and KM in a median of 10 days. CONCLUSION: TLA was an accurate method for the detection of resistance in the three drugs studied. This faster method is simple to perform, providing an alternative method when more sophisticated techniques are not available in low-resource settings

Neutral heavy lepton production at next high energy e+e−e^+e^- linear colliders

The discovery potential for detecting new heavy Majorana and Dirac neutrinos at some recently proposed high energy $e^+e^-$ colliders is discussed. These new particles are suggested by grand unified theories and superstring-inspired models. For these models the production of a single heavy neutrino is shown to be more relevant than pair production when comparing cross sections and neutrino mass ranges. The process $e^+e^- \longrightarrow {\nu} e^{\pm} W^{\mp}$ is calculated including on-shell and off-shell heavy neutrino effects. We present a detailed study of cross sections and distributions that shows a clear separation between the signal and standard model contributions, even after including hadronization effects.Comment: 4 pages including 15 figures, 1 table. RevTex. Accepted in Physical Review

Modulation of tomato pericarp firmness through pH and calcium: Implications for the texture of fresh-cut fruit

The effect of pH and calcium on pericarp firmness and pectin solubility was investigated in tomato fruit (Lycopersicon esculentum Mill. ‘Tavira’). Pericarp disks were vacuum-infiltrated with 50mM CaCI₂ or with distilled water and incubated for 4 h in buffer solutions at pH 4.5 and 7.0, and subsequently stored at 2 ◦C for 5 days. CaCl2 treatment had a significant effect on firmness retention in disks from turning and ripe fruit. Pericarp disks from mature-green fruit infiltrated with CaCl2 were firmer than untreated tissue after a 4 h incubation period, but the effect of calcium did not persist during storage at 2 ◦C. pH had a significant effect on the firmness of pericarp disks excised from turning and ripe fruit, but not on mature-green tissue. Treatments at pH 7.0 caused a reduction of the softening rate in disks from turning and ripe fruit, but had no significant effect at the mature-green stage. Water-soluble pectins decreased significantly in mature-green and ripe pericarp tissue following treatment with CaCl2 at pH 7.0, suggesting that pH affects pectin dissolution. Firmness changes induced by pH and calcium after a 4 h incubation treatment were highly correlated with pectin dissolution. The results indicate that, besides calcium, pH contributes to textural changes in tomato fruit pericarp. Since wounding inflicted during processing and acidic solutions used to prevent enzymic browning and microbial growth are likely to acidify the apoplast of fresh-cut fruit, the ability to maintain an apoplastic pH near 7.0 can significantly contribute to enhanced firmness of fresh-cut fruit

Digital image processing and enhancement of gravity data as an aid to the definition of the structural framework of the north Tucano-Jatobá basins, Northeastern Brazil

Técnicas de processamento digital de imagens foram aplicadas a dados gravimétricos visando melhorar definição das principais feições estruturais na porção norte do Rift Recôncavo-Tucano-Jatobá. Os processamentos utilizados incluíram: (a) conversão de dados Bouguer e residual-Bouguer, no formato de grids, em imagens realçadas; (b) geração de composições falsa cor híbridas e (c) geração de modelos de elevação digital com visão em perspectiva. A análise integrada desse conjunto de dados permitiu reconhecer feições lineares e sutis variações espaciais nos dados gravimétricos, as quais foram associadas a unidades tectónicas no contexto do rift, tais como: plataformas em rampa, baixos e altos estruturais, horsts, grabens e falhas de borda.Digitally processed and enhanced gravity data in raster format were used to improve the definition of the main structural features in the northern part of the Reconcavo-Tucano-Jatoba Rift. Image processing techniques included: (a) conversion of Bouguer and residual-Bouguer gridded data into contrast-enhanced gray-level images; (b) generation of enhanced hybrid pseudo-color composites; and (c) generation of a gravity digital elevation model in perspective views. The integrated analysis of this dataset permitted the recognition of subtle trends and intensity-related spatial variations in gravity data, tentatively related to the following tectonic units of the RTJ Rift: ramp platforms, structural lows and highs, along-length horsts, grabens, faulted borders and extensional faults

Cultivares de arroz de terras altas, BRS-Primavera e Maravilha, no Estado de Mato Grosso, no período de 1997/98 a 1999/00: impacto econômico.

Devido aos melhores atributos, tal como a qualidade de grãos, as novas cultivares de arroz de terras altas, BRS-Primavera e Maravilha, com grãos tipo agulhinha, entraram no mercado e se expandiram rapidamente, principalmente no Estado de Mato Grosso, substituindo, em parte, as cultivares tradicionalmente utilizadas. Este fato suscitou o interesse em medir a dinâmica de adoção destas cultivares neste Estado, bem como seu impacto na produção e na renda dos produtores.bitstream/item/59067/1/Foco-57.pd

Physicochemical quality, macronutrients, and dietary fiber in apples from the protected geographical indication ‘Maçã de Alcobaça’, Portugal

Apple is a major fruit in the European diet. The range of cultivar types and origins diversify the nutritional composition of apples. Eight apple cultivars (Malus xdomestica Borkh. 'Casa Nova', 'Fuji', 'Galaxy', 'Golden Delicious', 'Granny Smith', 'Jonagored', 'Reinette', and 'Starking') with the " Maca de Alcobaca" Protected Geographical Indication (PGI), Portugal, were harvested at commercial maturity, stored for 3 to 3.5 months at 0 degrees C, and characterized at the edible stage for their nutritional composition. Fruit quality was assessed by color, soluble solids content, titratable acidity, pH, Thiault index and firmness. The concentration moisture, dry matter, carbohydrates, protein, fat, ash, and fiber defined the nutritional profile. 'Reinette' had highest soluble solids content, titratable acidity, carbohydrates, protein, ash, energy, dry matter. 'Granny Smith' had the lowest soluble solids and carbohydrates contents, dry matter and energy. 'Casa Nova', a traditional cultivar, had high fiber content. Energy content varied by more than 30%, lowest in 'Granny Smith' and highest in 'Reinette', and is strongly correlated with dry matter and soluble solids content. The cultivarspecific range of nutritional value provides a basis for market segmentation based on nutritional content.info:eu-repo/semantics/publishedVersio

Learning from conflict in higher education

Due to its structural complexity, and its openness to diversity, universities are proneto conflict, and invest an enormous amount of time and energy to reconcile divergent interests. Thus, conflict is an integral part of academic life, including the classroom, although in this latter case, it is seen as an uncomfortable issue. In fact, as teachers rarely assume that do not have control of their classes, as actually happens often, conflict in the classroom is a matter whose discussion tends to be avoided to not harm the personal and organizational image. As a result, teachers have little or no training to deal with these problems. Although students and teachers may differ on the extent and significance of inappropriate behaviors in the classroom, the extant literature on this issue indicates that there is some consensus on the fact that interpersonal conflicts often result from the interaction between students' "uncivilized" acts and teachers' negative approaches. This presentation focus on the crucial skills to deal constructively with these problematic situations, through two complementary directions. Firstly, we present the foundations of an intervention model for dealing with conflicts among students and between them and the teachers, in order to minimize the negative impact on relationships, and simultaneously take advantage of the learning potential of well managed conflicts, guiding its resolution for a solution-finding process. Secondly, we discuss the concept of "problem" as a central tool of a pedagogical strategy to stimulate learning from the resolution of didactically relevant cases, which are based on real situations taken from and similar to those that students will encounter in a professional context. These problems are always presented under the format of cognitive conflicts, and embedded in a specific context. Through a sequential approach, cognitive conflicts contribute to a meaningful learning that facilitates the acquisition of knowledge and the discovery of its applicability. A case in the field of management education to illustrate the method is presented and discussed in the framework of Problem-Based Learning (PBL) strategies.info:eu-repo/semantics/publishedVersio