Characterization of Blue Agave Bagasse (BAB) as Raw Material for Bioethanol Production Processes by Gravimetric,Thermal, Chromatographic,X-ray Diffraction,Microscopy, and Laser Light Scattering Techniques

A detailed characterization of the main types of blue agave bagasse (BAB) obtained from the four largest tequila factories in the State of Jalisco (Mexico) is presented here. After milling/sieving the agave bagasses, two particle size fractions were identified, one rich in fibers and the other consisting of dust/fine particles. Both fractions were analyzed to determine the content of cellulose, hemicellulose, lignin, organic-soluble compounds, absorbed remaining sugars, minerals, and organic matter. After detailed analyses of both fractions by wet, thermal (thermo-gravimetric analysis (TGA)/differential thermo-gravimetric analysis (DTA)), and other methods (high-performance liquid chromatography (HPLC), microscopy, particle size by laser diffraction light scattering, and crystallinity by X-ray diffraction), a moderate-to-intensive method was devised for further processing the fibrous fraction, which had a high crystalline cellulose content, as well as for its subsequent enzymatic saccharification under well-defined moderate conditions. Alternative processing options were also devised for the dust/fine particle fraction, which has a moderate crystalline cellulose that is rich in adsorbed sugars and that has a high mineral matter content.     

Scanning isoelectric focusing of cholera enterotoxin in polyacrylamide gels

Scanning isoelectric focusing has been employed for continuous monitoring of the isoelectric spectrum of highly purified cholera enterotoxin in 4% polyacrylamide gels containing 2% ampholytes pH 3–10. The resolution obtained by this technique is of high order because at no instance during focusing interruption of current occurs and thus diffusion of the isolated protein moieties is suppressed. An added aspect of scanning isoelectric focusing was that it allowed estimation of the minimal focusing time of cholera enterotoxin. Thus under the standard assay procedure, the main basic component of cholera enterotoxin was focused in 5800 sec, while the other at least 3 minor acidic and anodic components were focused in approximately 19000 sec. Focusing of cholera enterotoxin in the presence of 6m urea allowed the visualization of 5 well defined and about equal components. The proteinaceous nature of the observed peaks was verified by scanning at wavelengths other than 280 nm, staining of gels for protein, and varying the concentration of the enterotoxin. The design of scanning isoelectric focusing equipment is presented. Reproducibility, economy of sample, and ampholytes and simplicity of experimental technique were some of the features of this apparatus. The resolution of scanning isoelectric focusing was found to be superior to that of ordinary disc and SDS gel electrophoresis.     

Evaluation of an endo-β-mannanase produced by Streptomyces ipomoea CECT 3341 for the biobleaching of pine kraft pulps

An endo-beta-mannanase (EC 3.2.1.78) from Streptomyces ipomoea CECT 3341 was purified and applied to the biobleaching of pine kraft pulps. The maximum level of endo-beta-mannanase activity (0.6 units ml(-1)) was achieved after 4 days of growth in a medium containing locust bean gum and yeast extract. Zymograms revealed mannanase bands (Man) with high and low electrophoretic mobility on the second and seventh days of incubation (Man1, Man3) and three bands of high, medium and low mobility from the third to sixth days of growth (Man1, Man2, Man3). Although these exhibited different molecular masses, their amino-terminal sequences were identical. The action of proteases detected in the culture supernatant could be responsible for such events, suggesting that only one endo-beta-mannanase is produced by S. ipomoea. The purified Man3 exhibited a molecular mass of 40 kDa, an isoelectric point of 4.0 and an optimal temperature and pH reaction of 55 degrees C and 7.5, respectively. It was strongly inhibited by Ag+, Hg2+, Al3+ and Fe3+, and was strongly activated by Mn2+. The ability of the purified endo-beta-mannanase to improve the bleachability of pine kraft pulp, when applied with alkaline extraction, was demonstrated by an increase in the pulp brightness (1.7%, using the International Standards Organisation's test) and an absence of variations in the viscosity values. A relationship between the increase in pulp brightness and the presence of manganese in the pulps could be established.     

Spatial, seasonal and diel distribution patterns of two species of mojarras (Pisces: Gerreidae) in a Mexican tropical coastal lagoon

Spatial, seasonal and diel distribution patterns were analysed over a 2‐year period for Diapterus auratus and Eucinostomus melanopterus in Pueblo Viejo lagoon, a tropical coastal lagoon in Veracruz, Mexico. A total of 216 samples were collected with 329 individuals of D. auratus and 170 of E. melanopterus. Diapterus auratus individuals were captured throughout a wider range of environmental conditions, and consequently its spatial niche breadth was significantly greater (P < 0.001) than that of E. melanopterus. In general, more individuals were captured at localities with submerged vegetation (Ruppia maritima), with 70% for D. auratus and 87.2% for E. melanopterus, although only the latter species showed significant spatial differences. A spatial segregation influenced by distance from the lagoon inlet and salinity was observed between the species. It is considered that this segregation may allow resource partitioning and minimize interspecific competition. A relatively low niche overlap (4.9%) was observed for the two species. Seasonal capture peaks of D. auratus were related to rainfall and the productivity pattern in the lagoon system. Seasonal fluctuations in monthly mean number of D. auratus were correlated with preceding variations in local rainfall (r = 0.86, P < 0.02). Moreover, seasonal capture peaks of D. auratus coincided with ecosystem primary production peaks. Although E. melanopterus exhibited no significant seasonal differences, its maximum numbers also coincided with an ecosystem primary production peak and recruitment patterns. In 24‐h cycle analysis, both species were captured mainly around mid‐day, with minor peaks at dawn and/or at dusk. Generally, few individuals were collected during hours of darkness. It was proposed that diel abundance variation of gerreids might be related to both light penetration in the water column and feeding activity. Food availability within Pueblo Viejo lagoon appears to be an important factor influencing fish abundance.     

Molecular phylogenetics at the population/species interface in cave spiders of the southern Appalachians (Araneae:Nesticidae:Nesticus)

This paper focuses on the relationship between population genetic structure and speciation mechanisms in a monophyletic species group of Appalachian cave spiders (Nesticus). Using mtDNA sequence data gathered from 256 individuals, I analyzed patterns of genetic variation within and between populations for three pairs of closely related sister species. Each sister-pair comparison involves taxa with differing distributional and ecological attributes; if these ecological attributes are reflected in basic demographic differences, then speciation might proceed differently across these sister taxa comparisons. Both frequency-based and gene tree analyses reveal that the genetic structure of the Nesticus species studied is characterized by similar and essentially complete population subdivision, regardless of differences in general ecology. These findings contrast with results of prior genetic studies of cave-dwelling arthropods that have typically revealed variation in population structure corresponding to differences in general ecology. Species fragmentation through both extrinsic and intrinsic evolutionary forces has resulted in discrete, perhaps independent, populations within morphologically defined species. Large sequence divergence values observed between populations suggest that this independence may extend well into the past. These patterns of mtDNA genealogical structure and divergence imply that species as morphological lineages are currently more inclusive than basal evolutionary or phylogenetic units, a suggestion that has important implications for the study of speciation mechanisms.      

Controversies Regarding the Psychometric Properties of the Brief COPE: The Case of the Brazilian-Portuguese Version “COPE Breve”

The Brief Coping Orientation to Problems Experienced (COPE) inventory investigates the different ways in which people respond to stressful situations. Knowledge is lacking regarding the coping strategies and styles of people in developing countries, including Brazil. This study aimed to adapt and validate the Brief COPE to Brazilian Portuguese (named COPE Breve) by focusing on dispositional coping. For the cross-cultural adaptation, the original Brief COPE in English (28 items grouped into 14 subscales) was adapted according to a universalistic approach, following these steps: translation, synthesis, back-translation, analysis by an expert panel, and pretest with 30 participants. Then, 237 adults from the community health service responded to the COPE Breve. Psychometric analyses included reliability and exploratory factor analysis. Most of the 14 subscales from the original Brief COPE exhibited problems related to internal consistency. A Velicer''s minimum average partial test (MAP) was performed and pointed out 3 factors. Exploratory factor analysis produced a revised 20-item version with a 3-factor solution: religion and positive reframing, distraction and external support. The psychometric properties of the COPE Breve with three factors were appropriate. Limitations of this study as well as suggestions for future studies are presented. The COPE Breve should be used in Brazilian clinics and investigations, but divergences in its psychometrics should be further explored in other contexts.     

Characterization of human chromosomal DNA sequences which replicate autonomously in Saccharomyces cerevisiae.

We have characterised two restriction fragments, isolated from a "shotgun" collection of human DNA, which function as autonomously replicating sequences (ARSs) in Saccharomyces cerevisiae. Functional domains of these fragments have been defined by subcloning and exonuclease (BAL 31) deletion analysis. Both fragments contain two spatially distinct domains. One is essential for high frequency transformation and is termed the Replication Sequence (RS) domain, the other, termed the Replication Enhancer (RE) domain, has no inherent replication competence but is essential for ensuring maximum function of the RS domain. The nucleotide sequence of these domains reveals several conserved sequences one of which is strikingly similar to the yeast ARS consensus sequence.     

Interleukin-23 is critical for full-blown expression of a non-autoimmune destructive arthritis and regulates interleukin-17A and RORγt in γδ T cells

Introduction  

Interleukin (IL)-23 is essential for the development of various experimental autoimmune models. However, the role of IL-23 in non-autoimmune experimental arthritis remains unclear. Here, we examined the role of IL-23 in the non-autoimmune antigen-induced arthritis (AIA) model. In addition, the regulatory potential of IL-23 in IL-17A and retinoic acid-related orphan receptor gamma t (RORγt) expression in CD4⁺ and TCRγδ⁺ T cells was evaluated systemically as well as at the site of inflammation.