In-depth search focused on furans, lactones, volatile phenols, and acetals as potential age markers of Madeira wines by comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry combined with solid phase microextraction

The establishment of potential age markers of Madeira wine is of paramount significance as it may contribute to detect frauds and to ensure the authenticity of wine. Considering the chemical groups of furans, lactones, volatile phenols, and acetals, 103 volatile compounds were tentatively identified; among these, 71 have been reported for the first time in Madeira wines. The chemical groups that could be used as potential age markers were predominantly acetals, namely, diethoxymethane, 1,1-diethoxyethane, 1,1-diethoxy-2-methyl-propane, 1-(1-ethoxyethoxy)-pentane, trans-dioxane and 2-propyl-1,3-dioxolane, and from the other chemical groups, 5-methylfurfural and cis-oak-lactone, independently of the variety and the type of wine. GC × GC-ToFMS system offers a more useful approach to identify these compounds compared to previous studies using GC−qMS, due to the orthogonal systems, that reduce coelution, increase peak capacity and mass selectivity, contributing to the establishment of new potential Madeira wine age markers. Remarkable results were also obtained in terms of compound identification based on the organized structure of the peaks of structurally related compounds in the GC × GC peak apex plots. This information represents a valuable approach for future studies, as the ordered-structure principle can considerably help the establishment of the composition of samples. This new approach provides data that can be extended to determine age markers of other types of wines.

The Predation of Artemia Nauplii by the Larvae of the Amazon River Prawn, Macrobrachium amazonicum (Heller, 1862), is Affected by Prey Density, Time of Day, and Ontogenetic Development

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Dispersion of Seeds of Tree Species by the Leaf-Cutting Ant Acromyrmex subterraneus molestans (Hymenoptera: Formicidae) in Vicosa, Minas Gerais State, Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relationships between physical, morphological, and physiological characteristics of seeds developed at different positions of the ear of two maize (Zea mays L.) hybrids

Maize seeds developed at different portions of the ear of two hybrids (one, a large seeded, and the other a small seeded hybrid) were compared as to physical positions, morphological, and physiological characteristics viewing to gain information to be used during seed conditioning. The number of positions in the ear were 10, starting at the proximal and ending at the distal end. For the sake of simplification, the data were combined to refer to seeds of the proximal, the central and the distal sectors of an ear. Measurements made of the seeds as to shape (length, width, and thickness) and as to size (1,000 seeds weight) indicated that the round seeds growing at the distal sector are significantly smaller (mainly when thickness is considered) and lighter than those growing at the proximal sector. on the other hand, determinations of the physiological quality indicated that the round-proximal and the central seeds are equivalent and both significantly superior to the round-distal ones, Considering these significant differences as to size, shape, and physiological quality, a proposition of suppressing part of the round-distal from the totallity of the round seeds during the operations of seed conditioning is made.

Influence of the temperature in germination of seeds of jabuticaba tree

A jabuticabeira (Myrciaria spp.) é uma fruteira originada do centro-Sul do Brasil e apresenta tipos diferentes. É uma árvore de tamanho médio, com tendência a formar copa com grande número de ramos desde pouco acima do solo. Uma característica considerada como limitante para a cultura comercial dessa frutífera é o grande período juvenil, aconselhando-se então produzir bons porta-enxertos de pés-francos e enxertar as variedades desejadas, ou ainda por outros processos vegetativos. Objetivando-se avaliar a influência da temperatura na germinação de sementes de três clones de jabuticabeira, realizou-se um experimento em condições de laboratório. Observou-se que há influência da temperatura na porcentagem de germinação, sendo que, nas mais baixas temperaturas (15ºC e 20ºC), foi verificada uma maior porcentagem de germinação para os três clones em estudo. Quando do uso da temperatura de 35ºC, dois clones tiveram apenas 8% de germinação, enquanto, para o outro, foi verificado 35%. Estes dados mostram a possibilidade de ocorrência de variabilidade entre clones de jabuticabeira.

Genetic diversity of three size classes of seeds of Eucalyptus globulus ssp. globulus

Variation in seed size is often observed in samples of eucalypt seeds and this leads to heterogeneous populations of plants, principally through variation in the early stages of plant development. It follows that samples of seeds more uniform in size could produce more uniform populations of plants. In studies of Eucalyptus globulus ssp. globulus it was of interest to determine whether or not the genetic diversity within a population, through the use of isozyme markers, was altered in the subpopulations developed from seeds of different size classes. A commercial sample of seed was separated by seed size into three subpopulations and the percentage germination and mean fresh weight of the seedlings were determined. Proteins extracted from leaves of the seedlings were separated by electrophoresis and tested for activity of eight different enzymes. These eight enzymes showed activity at 20 loci and mean genetic diversity and fixation index were determined using 13 of these loci. The subpopulation of the smallest seeds contained a greater proportion of abnormal seeds and had a lower percentage germination and plant weight compared to the other subpopulations. No significant differences were found in the number of alleles per locus, percentage of polymorphic loci, mean heterozygosity. The major part of the endogamy, indicated by F statistic, was found within the subpopulations: F-(IS) = 0.518; F-(ST) = 0.010 and F(IT) = 0.523. We conclude that the use of seeds of uniform size will lead to more uniform germination and plant growth without alteration in overall genetic diversity.

Genetic and environmental factors that affect the best time of Thoroughbred horses in Brazil

On the basis of information provided by the Brazilian Association of Race Horse Breeders, we analysed the racing performance of 947 Thoroughbred horses in races held from 1985 to 1992. The performance was evaluated using the best, time of the animals. The variance component was obtained by the derivative-free restricted maximum likelihood method, and the model used contained fixed effects of the racing month and year, sex, race track, track condition, animal age, number of competitors in race, and distance, and the random animal effect. The low heritability estimate obtained (0.12) indicates that selection based on animal phenotypic value must induce small genetic changes in this trail.

Effect of application time of APF and NaF gels on microhardness and fluoride uptake of in vitro enamel caries

Purpose : To evaluate the effect of time of fluoride application gel, acidulated or neutral, on in vitro enamel resistance to demineralization and fluoride uptake. Materials and Methods: One hundred and ninety-two human enamel blocks were used in this study and 144 were treated with fluoride gel, acidulated or neutral, for I or 4 minutes. Ninety-six blocks treated with fluoride and 24 control blocks were submitted to a high cariogenic challenge. After the pH-cycling, enamel demineralization was assessed by surface and cross-sectional microhardness. Fluoride in the enamel blocks was also determined after removing an enamel layer by etching acid. Results: Acidulated fluoride gel formed more fluoride in enamel than neutral gel (P < 0.05), and it was also more efficient in reducing the demineralization of the enamel blocks submitted to a cariogenic challenge than the neutral one (P < 0.05). It was found that the time of application was significant in terms of fluoride uptake, but it did not render the enamel more resistant to dernineralization.

pH, Calcium Ion Release, and Setting Time of an Experimental Mineral Trioxide Aggregate-based Root Canal Sealer

Introduction: An experimental mineral trioxide aggregate sealer (MTAS) has been developed for use as a root canal sealer. The aim of this study was to evaluate the setting time, pH, and calcium ion release of MTAS compared with white Portland cement (CPB-40; Votorantin Cimentos, Camargo Correa SA, Pedro Leopoldo, MG, Brazil), white MTA Angelus (MTA; Angelus, Londrina, PR, Brazil), and AH Plus (Dentsply DeTrey, Konstanz, Germany). Methods: For the evaluation of setting time, each material was analyzed using Gilmore-type needles. Polyethylene tubes with the materials were immersed in distilled water for the measurement of pH (digital pH meter) and calcium release (atomic absorption spectrophotometry). The evaluations were performed at 3, 6, 12, 24, and 48 hours and 7, 14, and 28 days. Data were analyzed by analysis of variance and the Tukey test at 5% significance level. Results: MTAS showed higher calcium release at all experimental periods, a greater increase in pH up to 48 hours and the longest setting time. Conclusions: MTAS presented favorable properties for its indication as a root canal sealer. (J Endod 2011;37:844-846)

A Case Study: The Effect of Visitors on Two Captive Pumas With Respect to the Time of the Day

This study analyzed the effects of noise levels and number of visitors on the behaviors of a mother puma and her daughter in a zoo environment with respect to the time of day. The study monitored visitation (noise and number) over two 1-week periods (4 weeks between periods) and frequency of various puma behaviors (videorecorded). The study analyzed videotaped behavior of the pumas based on the time of day and visitors number and noise levels. There was a direct association of puma behaviors with visitors number and noise levels. The daughter puma was the most affected and behavioral changes of both pumas correlated more strongly with the noise level than the number of visitors. The noise level and number of visitors affected the behavior of the mother and her daughter only in the morning. The results of this study indicate that both noise level and number of visitors affected these pumas but revealed the noise as predominant. Moreover, the response of these pumas to visitors depended on the time of the day.

Advantages of using nested collision induced dissociation/post-source decay with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry: sequencing of novel peptides from wasp venom

We have examined the applicability of the 'nested' collision induced dissociation/post-source decay (CID/PSD) method to the sequencing of novel peptides from solitary wasps which have neurotoxic venom for paralyzing other insects. The CID/PSD spectrum of a ladder peptide derived from an exopeptidase digest was compared with that of the intact peptide. The mass peaks observed only in the CID/PSD spectrum of a ladder peptide were extracted as C-terminal fragment ions. Assignment of C-terminal fragment ions enabled calculation of N-terminal fragment masses, leading to differentiation between N-terminal fragment ions and internal fragment ions. This methodology allowed rapid and sensitive identification by removing ambiguity in the assignment of the fragment ions, and proved useful for sequencing unknown peptides, in particular those available as natural products with a limited supply. Copyright (C) 2000 John Wiley & Sons, Ltd.

Seed deposition patterns and the survival of seeds and seedlings of the palm Euterpe edulis

The seed deposition pattern created by a seed disperser is one of the components of the efficiency of a species as seed disperser, and ultimately may influence the recruitment of a plant species. In this study, we used the seeds of a bird-dispersed forest palm, Euterpe edulis, to investigate the effects of two distinct seed deposition patterns created by birds that defecate (clumped pattern) and regurgitate seeds (loose-clumped pattern) on the survival of seeds experimentally set in an E. edulis-rich site, and of seedlings grown under shade-house conditions. The study was conducted in the lowland forest of Parque Estadual Intervales, SE Brazil. Clumped and loose-clumped seeds were equally preyed upon by rodents and insects. Although clumped and isolated seedlings had the same root weight after 1 year, the isolated seedlings survived better and presented more developed shoots, suggesting intraspecific competition among clumped seedlings. Our results indicate that animals that deposit E. edulis seeds in faecal clumps (e.g. cracids, tapirs) are less efficient seed dispersers than those that regurgitate seeds individually (e.g. trogons, toucans). Intraspecific competition among seedlings growing from faecal clumps is a likely process preventing the occurrence of clumps of adult palms. (C) 2001 Editions scientifiques et medicales Elsevier SAS.