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Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In mixedwood boreal forests of western Canada, stands classified as 'pure deciduous' by forest inventories sometimes contain a few large white spruce (Picea glauca (Moench) Voss) trees among or emerging from the canopy. These trees are important as regeneration seed sources and for habitat structure. Neither their abundance nor the characteristics of stands in which they occur have previously been quantified. Of 275 'pure aspen' stands in northeastern Alberta, 19.6% contained at least one such spruce detectable in an aerial photograph. These trees were found in stands across the range of sampled canopy heights, densities, age classes, and stand sizes and were often present in the interior of stands, not just on the perimeter. The frequency of 3 ha cells containing at least one spruce was related to (i) stand shape and size, (ii) amount of mature white spruce in adjacent forest, (iii) canopy height, (iv) stand age, and (v) stand density. We conclude that such trees are relatively abundant and widely distributed within the boreal mixedwood forests of Alberta. There is presently no provision to maintain this landscape element within managed forests. More information is needed to determine if or how they should be considered in forest management planning. Dans la foret boreale mixte de l'Ouest canadien, il arrive que les peuplements classes comme << feuillus purs >> dans les inventories forestiers contiennent quelques grosses tiges d'epinette blanche (Picea glauca (Moench) Voss) qui font partie ou emergent de la canopee. Ces arbres sont importants comme source de graines pour la regeneration et pour la structure de (habitat. Toutefois, leur abundance et les caracteristiques des peuplements dans lesquels ils sont presents n'ont jamais ete quantifiees. Parmi 275 << peupleraies pures >> du nord-est de (Alberta, 19,6 % contenaient au moms une telle epinette detectable a partir de photographies aeriennes. Ces arbres ont ete detectes dans des peuplements couvrant toute la gamme de hauteurs de canopee, de densites, de classes d'age et de tailles de peuplement echantillonnees; ils etaient souvent presents a finterieur des peuplements et non seulement en peripherie. La frequence des cellules de 3 ha a contenant au moms une epinette a ete reliee a (i) la forme et la taille du peuplement, (ii) la quantite d'epinettes blanches matures dans la foret adjacente, (iii) la hauteur de la canopee, (iv) Page du peuplement et (v) la density du peuplement. Nous concluons que de tels arbres sont relativement abondants et largement distrbbues dans la foret boreale mixte de l'Alberta. Il n'y a presentement aucune mesure visant a maintenir cet element du paysage dans les foress amenagees. Plus de renseignements sont necessaires pour determiner si ou comment ces arbres devraient etre consideres dans la planification de l'amenagement forestier. [Traduit par la Redaction], Introduction In the boreal mixedwood forests of western Canada, the canopies of upland mesic sites are dominated by some combination of Populus species (typically trembling aspen, Populus tremuloides Michx., but [...]

Ceftriaxone sodium is a widely used antimicrobial, which is only available as a lyophilized powder. The presence of methods for evaluating the quality of this product is very important and helps to ensure its effectiveness, in addition to contributing to the fight against bacterial resistance. Therefore, a clean and sustainable high-performance liquid chromatography (HPLC) method has been developed for evaluating ceftriaxone stability in pharmaceutical product. A Zorbax SB C18 (150 × 4.6 mm, 5 μm) column was maintained at 25°C; the mobile phase consisted of purified water acidified with 0.2% orthophosphoric acid and ethanol (87: 13, v/v) at a flow rate of 0.9 mL min−1. The detection wavelength was set at 260 nm. The method was linear over a concentration range of 20–120 μg mL−1, precise with relative standard deviations <2%, robust in the event of minor changes to the original method conditions, accurate with recovery between 98% and 102% and specific to degradation products. The retention time for ceftriaxone sodium was ~4.6 minutes. This work shows an ecologically correct option by HPLC method for the evaluation of ceftriaxone sodium in pharmaceutical product, as well as its stability, which addresses the requirements of the current green and sustainable analytical chemistry. [ABSTRACT FROM AUTHOR]

Background: Ceftriaxone sodium, an antimicrobial used in parenteral form, does not have a microbiological method by turbidimetry described in the literature. For drugs from antimicrobial class, the existence of a microbiological method for assessing their potency is essential. Not only are the results from the physical-chemical methods enough, but microbiological analyzes are also necessary. Objective and Methods: Thus, this paper reports the development and validation of an efficient, accurate, reproducible, fast, and low-cost microbiological assay by turbidimetry to quantify ceftriaxone sodium in powder for injection. Water was used as the diluent to prepare the ceftriaxone solutions. BHI broth as used as culture media for the growth of the S. aureus ATCC 6538 at 9%. Results: The method was linear in the range of 100–196 mg/mL, selective against the sample adjuvants and the forced degradation test, precise (intraday RSD 4.53%, interday RSD 3.85% and between analysts tcalculated 0.14<2.23 tcritical), accurate with recovery of 100.33% and robust against minor changes in the volume of culture medium used, wavelength, incubation time, and inoculum concentration. Conclusions and Highlights: The turbidimetric method developed in this paper is a convenient and valuable alternative to the routine quality control of ceftriaxone sodium in powder for injection, since it allows a reliable quantification and can be used to complement the physical-chemical analysis. [ABSTRACT FROM AUTHOR]

Ceftriaxone sodium is a third-generation semi-synthetic antibiotic belonging to the class of cephalosporins. Is administered only by parenteral route and has the ability to cross the blood-brain barrier. It has bactericidal action; its main activity is related to the Gram-negative bacteria, being also able to act against Gram-negative bacilli resistant to the first- and second-generation cephalosporins. The present study presents a survey of the characteristics, properties and analytical methods used for the determination of ceftriaxone sodium, for the gathering of data searches were carried out in scientific articles in the world literature, as well as in the official compendia. It is necessary to create awareness about the importance of developing effective and reliable analytical methods for quality control and consequently for conducting pharmacokinetic, bioavailability, bioequivalence studies as well as for the therapeutic monitoring of this drug. Most of the methods found use high-performance liquid chromatography, but also methods that use absorption spectroscopy ultraviolet, infrared spectroscopy, spectrofluorimetry and microbiological methods have been presented. A discussion was presented highlighting the need to develop new ecological methods using less toxic solvents, rapid analysis and miniaturization of the samples. [ABSTRACT FROM AUTHOR]

Diabetes mellitus (DM) is considered a public health problem. The initial treatment consists of improving the lifestyle and making changes in the diet. When these changes are not enough, the use of medication becomes necessary. The metformin aims to reduce the hepatic production of glucose and is the preferred treatment for type 2. The objective is to survey the characteristics and properties of metformin, as well as hold a discussion on the existing analytical methods to green chemistry and their impacts for both the operator and the environment. For the survey, data searches were conducted by scientific papers in the literature as well as in official compendium. The characteristics and properties are shown, also, methods using liquid chromatography techniques, titration, absorption spectrophotometry in the ultraviolet and the infrared region. Most of the methods presented are not green chemistry oriented. It is necessary the awareness of everyone involved in the optimization of the methods applied through the implementation of green chemistry to determine the metformin. [ABSTRACT FROM AUTHOR]

In mixedwood boreal forests of western Canada, stands classified as “pure deciduous” by forest inventories sometimes contain a few large white spruce (Picea glauca (Moench) Voss) trees among or emerging from the canopy. These trees are important as regeneration seed sources and for habitat structure. Neither their abundance nor the characteristics of stands in which they occur have previously been quantified. Of 275 “pure aspen” stands in northeastern Alberta, 19.6% contained at least one such spruce detectable in an aerial photograph. These trees were found in stands across the range of sampled canopy heights, densities, age classes, and stand sizes and were often present in the interior of stands, not just on the perimeter. The frequency of 3 ha cells containing at least one spruce was related to (i) stand shape and size, (ii) amount of mature white spruce in adjacent forest, (iii) canopy height, (iv) stand age, and (v) stand density. We conclude that such trees are relatively abundant and widely distributed within the boreal mixedwood forests of Alberta. There is presently no provision to maintain this landscape element within managed forests. More information is needed to determine if or how they should be considered in forest management planning. [ABSTRACT FROM AUTHOR]

This study presents the first black spruce, balsam fir and larch tree ring width chronologies from Labrador. It uses a multi-species perspective to study the radial growth response of alpine treeline species in the Mealy Mountains to local and regional climate variables using bootstrapped correlation analysis. The radial growth response of black and white spruce trees is positively sensitive to growing season air temperatures and sea surface temperatures (SSTs) in the vicinity of the Grand Banks. Moisture originating from warm SSTs in the adjacent Labrador Sea appears to affect moisture-sensitive white spruce and balsam fir trees negatively in the Mealy Mountains. Comparative analysis of 4 tree-ring time series indicates that periods of larch sawfly outbreaks have occurred in the Mealy Mountains and that these events exert a significant amount of influence on the radial growth of larch trees in the Mealy Mountains. These inferred periods of insect infestations coincide with others reported in Quebec. Growing season (June-September) temperature is reconstructed for the Mealy Mountains using merged spruce tree ring width chronologies (1847-2004). The reconstruction is in accordance with other reconstructions at regional and hemispheric scales. The sensitivity of spruce trees to local temperature and precipitation is unstable throughout the period of instrumental record due to moisture effects. Further, spruce trees in the Mealy Mountains show evidence of divergence from air temperatures over the last several decades. [ABSTRACT FROM AUTHOR]