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Syrah must was co-inoculated with mixed cultures of Saccharomycesâ¯+â¯O. oeni/Lb. plantarum and Saccharomycesâ¯+â¯non-Saccharomycesâ¯+â¯O. oeni/Lb. plantarum to evaluate the effect on phenolics and sensory attributes. Reference wines were produced by S. cerevisiae. Malvidin-3-O-glucoside, flavan-3-ols, flavonols and phenolic acids were quantified using a RP-HPLC technique. Physicochemical characteristics and sensory attributes were measured. Total acidity and alcohol in mixed co-inoculations were different from reference wines. The concentration of l-malic acid was 7-times less in mixed co-inoculations. Mixed co-inoculations had ca. 1.3-times more malvidin-3-O-glucoside and phenolic acids than reference wines. Flavan-3-ols and flavonols were not different between mixed co-inoculations and reference wines. Acidity and astringency were least in mixed co-inoculations. Mouthfeel and bitterness least in S. cerevisiae wines. Tasters preferred mixed co-inoculated wines. Mixed co-inoculation is a strategy to contemplate for Syrah vinification but the modalities of inoculation need further investigation. Success depends on a suitable combination of yeast/bacteria and consideration of strain variation.
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Transgenic Bt maize expressing Cry insecticidal δ-endotoxins of Bacillus thuringiensis has been cultivated in South Africa for the control of Busseola fusca since 1998. Busseola fusca is resistant to Cry1Ab Bt maize at many localities throughout the maize production region. Pre-release evaluation (1994-1996) of the inherent susceptibility and post-release assessments (1998-2011) of resistance status of B. fusca focused on a limited number of pest populations. This study reports the current levels of susceptibility of 10 B. fusca populations evaluated between 2013 and 2017 and compared this data with previously reported data on the survival of this pest on Bt maize, including data of pre-release evaluations done during 1994 and 1995. Larval feeding bioassays in which plant tissue of maize events expressing either Cry1Ab or Cry1A.105+Cry2Ab2 (stacked event) proteins were conducted and survival and different life history parameters recorded. Results show a shift in levels of susceptibility of B. fusca to Bt maize. Pre-release evaluation of the single-gene event showed very low larval survival on Bt maize leaf tissue while studies 10 yr later and the current study reported survival of up to 40% and 100% on Cry1Ab maize, respectively. While no larvae completed their life cycle on the stacked event, higher LT50 values in this study indicate a shift in susceptibility of B. fusca to the stacked-gene event and highlight the importance of baseline information and monitoring of pest populations for their susceptibility to Bt maize.
Assuntos
Proteínas de Bactérias , Endotoxinas , Proteínas Hemolisinas , Mariposas , Animais , Toxinas de Bacillus thuringiensis , Feminino , Resistência a Inseticidas , Larva/crescimento & desenvolvimento , Masculino , Plantas Geneticamente Modificadas , África do Sul , Zea mays/genéticaRESUMO
Kei-apple (Dovyalis caffra) is an evergreen tree indigenous to Southern Africa. The fruit contains high concentrations of l-malic acid, ascorbic acid, and phenolic acids. Kei-apple juice was sequentially inoculated with Schizosaccharomyces pombe and Saccharomyces cerevisiae yeasts. A reference fermentation using only S. cerevisiae was included. The fermentation was monitored by recording mass loss. At the end of fermentation, twelve untrained judges conducted free choice aroma profiling on the fruit wines. The Kei-apple juice and wines were analysed for total titratable acidity, total soluble solids, pH, alcohol, l-malic acid, and phenolic acids. Total titratable acidity was ca. 70% lower in Kei-apple wines produced with S. pombe+S. cerevisiae than in Kei-apple juice. Kei-apple wines produced with S. pombe+S. cerevisiae showed substantially lower concentrations of l-malic acid than Kei-apple wines produced with S. cerevisiae only. Wines produced with S. cerevisiae only proved higher in phenolic acid concentrations than wines produced with S. pombe+S. cerevisiae. Chlorogenic acid was the most abundant phenolic acid measured in the Kei-apple wines, followed by protocatechuic acid. Judges described the Kei-apple wines produced with S. pombe+S. cerevisiae as having noticeable off-odours, while wines produced with S. cerevisiae were described as fresh and fruity. Kei-apple wines (S. pombe+S. cerevisiae and S. cerevisiae) were of comparable vegetative and organic character. Saccharomyces cerevisiae produced Kei-apple wine with increased caffeic, chlorogenic, protocatechuic, and sinapic acids, whereas S. pombe+S. cerevisiae produced Kei-apple wines with increased ferulic, and p-coumaric acids and low l-malic acid.
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Hidroxibenzoatos/análise , Malatos/análise , Saccharomyces cerevisiae/metabolismo , Salicaceae/microbiologia , Schizosaccharomyces/metabolismo , Vinho/análise , Vinho/microbiologia , Ácido Ascórbico/análise , Reatores Biológicos , Ácido Clorogênico/análise , Etanol/análise , Fermentação , Aromatizantes/análise , Frutas/química , Frutas/metabolismo , Odorantes/análiseRESUMO
Previous studies into third trophic level exposure of Chrysoperla spp. (Neuroptera: Chrysopidae) to Cry1Ab proteins produced by Bt crops yielded contradicting results. These contradictions were largely ascribed to differences in prey quality and exposure methods. In this study, we used healthy prey to expose lacewing larvae to Cry1Ab protein produced by Bt maize, and also determined the concentration of this protein at different trophic levels. Experiments were conducted in which Chrysoperla pudica (Navás) larvae were fed different diets which included aphids and healthy Bt-resistant Busseola fusca (Fuller) (Lepidoptera: Noctuidae) larvae feeding on Bt maize tissue. Lacewing larval and pupal development times as well as overall mortality were determined. The concentration of Cry1Ab protein in B. fusca larvae were fourfold reduced compared with that in leaf tissue and was below detection level in lacewing larvae. Survival to the pupal stage was higher than 96% in all treatments. Larval and pupal development periods did not differ significantly between treatments in which prey fed on Bt or non-Bt maize. This study showed feeding on healthy prey that consumed Cry1Ab protein has no adverse effect on the biology of C. pudica.
Assuntos
Bacillus thuringiensis/química , Proteínas de Bactérias/efeitos adversos , Endotoxinas/efeitos adversos , Proteínas Hemolisinas/efeitos adversos , Insetos/efeitos dos fármacos , Controle Biológico de Vetores , Plantas Geneticamente Modificadas/efeitos adversos , Zea mays/química , Animais , Afídeos/química , Bacillus thuringiensis/genética , Toxinas de Bacillus thuringiensis , Dieta , Insetos/crescimento & desenvolvimento , Larva/química , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Mariposas/química , Plantas Geneticamente Modificadas/química , Pupa/efeitos dos fármacos , Pupa/crescimento & desenvolvimento , Zea mays/genéticaRESUMO
The effect of temperature on the reproduction and development of Busseola fusca was studied under laboratory conditions. Single male-female pairs were confined to oviposition chambers kept at 15, 20, 26 and 30 ± 1°C and a 14L:10D photoperiod. Data on reproduction parameters were captured daily. Oviposition occurred at all the mentioned temperatures but no fertility was recorded at 30°C. The total number of eggs laid per female moth was between 300 and 400 and the optimum temperature for oviposition and fertility was between 20 and 26°C. Larval development was studied at five different temperature regimes, i.e. 15, 18, 20, 26 and 30 ± 1°C and a 14L:10D photoperiod. The most favourable temperature as well as the upper threshold temperature for larval development was between 26 and 30°C. Total development period was 152.6-52.6 days, respectively, at 15°C, and 26-30°C. The thermal constants for B. fusca was 99.50, 536.48, 246.25 and 893.66°D and lower temperature thresholds were 10.36, 8.14, 8.99 and 8.84°C, for completion of the egg, larval, pupal and egg-to-adult stages, respectively. Results on the thermal constants and lower and upper threshold temperatures of B. fusca can be used to predict the impact of climate change on the distribution and population growth of this pest.
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Mariposas/crescimento & desenvolvimento , Oviposição , Animais , Mudança Climática , Larva/genética , Óvulo/crescimento & desenvolvimento , Pupa/crescimento & desenvolvimento , Reprodução , TemperaturaRESUMO
Supported cobalt Fischer-Tropsch catalysts are characteristically nanoparticulate and the reduced SiC supported catalyst was found to contain both HCP and FCC polymorphs. This is reflected in the powder XRD patterns and generally there is a poor fit between the experimental and calculated diffractograms. This was ascribed to small crystallite sizes and the occurrence of disorder, manifested as peak broadening and peak shifts. Selected area electron diffraction data of suitably oriented cobalt catalyst grains on silicon carbide supports show non-periodic disorder in the zone axis orientations that contain the common (001) (HCP) and (111) (FCC) reciprocal lattice planes. Both FCC and HCP polymorphs are present in the same grains and these show disorder mainly in the HCP component. The disorder is further examined using high angle annular dark field (HAADF) scanning transmission electron microscopy at atomic resolution and the stacking sequences elucidated. Random sequences of mainly FCC are interrupted by HCP sequences and twin surfaces with reverse stacking sequences are also present. This study highlights the presence of significant disorder in cobalt catalyst grains confirmed by HAADF microscopy.
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Obesity is a global epidemic: it is estimated that the majority of the world's adults will be overweight or obese by 2030. It is therefore important to reverse trends towards increasing childhood obesity by interventions at the community level. Ensemble Prévenons l'obésité Des Enfants (EPODE, Together Let's Prevent Childhood Obesity) is a large-scale, coordinated, capacity-building approach for communities to implement effective and sustainable strategies to address this challenge. EPODE comprises four critical components: political commitment, public and private partnerships, community-based actions, and evaluation. The multi-stakeholder approach promoted through the EPODE methodology has already shown encouraging results in preventing childhood obesity in France and Belgium and has reduced the socioeconomic gap in obesity prevalence in France. The EPODE methodology has now been implemented in a number of countries worldwide, and provides a valuable model that may be applicable to other lifestyle-related diseases.
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iThemba Laboratory for Accelerator Based Science (iThemba LABS) is a multi-disciplinary accelerator facility. One of its main activities is the operation of a separated-sector cyclotron with a K-value of 200, which provides beams of various ion species. These beams are used for fundamental nuclear physics research in the intermediate energy region, radioisotope production, and medical physics applications. Due to the requirements of nuclear physics for new ion species and higher energies, the decision was made to install a copy of the so-called Grenoble test source (GTS) at iThemba LABS. In this paper, we will report on the experimental setup and the first results obtained with the GTS2 at iThemba LABS.
RESUMO
In brandy base wines, no sulphur dioxide is used and it therefore is ideal for the proliferation of lactic acid bacteria. As part of an extensive taxonomic survey within the ecological framework of South African vineyards and wineries, and the influence of naturally occurring lactic acid bacteria on the quality of wine and brandy, a total of 54 strains were isolated from grape juice and at different stages of brandy base wine production. The strains were identified using numerical analysis of total soluble cell protein patterns, 16S rRNA sequence analyses and polymerase chain reaction (PCR) using species-specific primers. The predominant species was Oenococcus oeni (22 strains), but Lactobacillus brevis (8 strains), Lactobacillus paracasei (8 strains) and Lactobacillus plantarum (6 strains) were also isolated frequently. Many of the O. oeni strains were isolated from brandy base wines after completion of spontaneous malolactic fermentation (MLF). The Lactobacillus spp. were isolated from all the different stages of brandy base wine production. Lb. plantarum was the dominant species in the juice, but disappeared during the later stages of production. However, Lactobacillus hilgardii, Lb. brevis and Lb. paracasei were also isolated from base wine after spontaneous MLF. Strains identified as Lactobacillus vermiforme were isolated during the alcoholic fermentation and after MLF have been completed. Total soluble cell protein patterns grouped O. oeni strains into two phenotypic groups. Two phenotypic clusters have also been identified for the Lb. brevis isolates. The Lb. paracasei isolates all grouped in one cluster. This is the first report of the presence of Lb. paracasei and Lb. vermiforme in brandy base wines. The presence of the Lactobacillus spp. could be correlated to the decrease in quality of the base wine and distillate, while O. oeni strains were found to have a more favourable influence on the quality of base wine and distillates. These results shed some light on the ecology and oenological influence of lactic acid bacteria (LAB) on the quality of South African brandy.
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DNA Bacteriano/análise , Microbiologia de Alimentos , Lactobacillus/classificação , Lactobacillus/isolamento & purificação , Vinho/microbiologia , DNA Bacteriano/genética , Fermentação , Filogenia , Reação em Cadeia da Polimerase/métodos , RNA Ribossômico 16S/análise , RNA Ribossômico 16S/genética , África do Sul , Especificidade da Espécie , Vinho/normasRESUMO
AIMS: In this study we determined the extent to which lactic acid bacteria (LAB) occurred in brandy base wines, their ability to catalyse the malolactic fermentation (MLF) and the effect of MLF on the quality of the base wine and the brandy distillate. METHODS AND RESULTS: Lactic acid bacteria were isolated and enumerated from grape juice, experimental and commercially produced brandy base wines. Spontaneous MLF occurred in approximately 50% of the commercial base wines. The occurrence of MLF had an influence on the quality of the base wines and the resulting distillates. In samples where MLF occurred there was a loss of fruitiness and in the intensity of aroma. Volatile compounds like iso-amyl acetate, ethyl acetate, ethyl caproate, 2-phenethyl acetate and hexyl acetate decreased in samples having undergone MLF, while ethyl lactate, acetic acid and diethyl succinate increased in the same samples. CONCLUSIONS: Spontaneous malolactic fermentation does occur in commercial brandy base wines and it has an influence on base wine and brandy quality. SIGNIFICANCE AND IMPACT OF THE STUDY: This study showed that MLF influences the quality of the base wine and the resulting distillate and with this in mind commercial base wine producers should be able to produce brandy of higher quality.
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Lactatos/metabolismo , Malatos/metabolismo , Vinho/microbiologia , Fermentação , Lactobacillus/isolamento & purificação , Lactobacillus/metabolismo , Odorantes , Streptococcaceae/isolamento & purificação , Streptococcaceae/metabolismo , Vitis/microbiologia , Vinho/normasRESUMO
Adenosine deaminase (ADA) exists as two isoenzymes, ADA(1) and ADA(2). It appears that the ADA(2) isoenzyme originates mainly from monocytes and macrophages. In tuberculous pleural effusions most of the ADA activity consists of ADA(2). The aim of this prospective study was to analyse ADA isoenzymes in the CSF of patients with meningitis to investigate whether the expected rise of the ADA(2) isoenzyme would occur in tuberculous meningitis. ADA isoenzyme analysis was performed on the CSF of 15 patients with tuberculous and 11 patients with bacterial meningitis by an automated kinetic enzyme coupled assay in the presence and absence of a specific ADA inhibitor. The ratio of ADA(2)/ADA(Total) was > 0.8 in 14/15 patients with tuberculous meningitis. In bacterial meningitis the ratio was > or =0.8 in 10/11 patients. The ADA(2) isoenzyme is the major contributor to increased ADA activity in the CSF of patients with tuberculous meningitis, probably reflecting the monocyte-macrophage origin of the ADA.
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Adenosina Desaminase/líquido cefalorraquidiano , Isoenzimas/líquido cefalorraquidiano , Tuberculose Meníngea/líquido cefalorraquidiano , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tuberculose Meníngea/enzimologiaRESUMO
Sulphuric acid in process effluent streams from an electrorefining copper plant was analysed with a sequential injection (SI) titration system using sodium hydroxide as titrant. In the proposed SI titration system a base titrant, acid analyte and base titrant zone were injected sequentially into a distilled water carrier stream in a holding coil and swept by flow reversal through a reaction coil to the detector. The base zones contained bromothymol blue as indicator and the endpoint was monitored spectrophotometrically at 620 nm. The influence of carrier stream flow rate, acid and base zone volumes and titrant concentration on the linear range of the method was studied to obtain an optimum. A linear relationship between peak width and logarithm of the acid concentration was obtained in the range 0.006-0.178 mol l(-1) of H(2)SO(4) for a NaOH concentration of 0.002 mol l(-1). The results obtained for the SI titration of process samples were in good agreement with a standard potentiometric method with an RSD<0.75% and a sample frequency of 23 samples h(-1).
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Two patients incurred barotrauma to the pharynx by the explosion of soft-drink bottles into their mouths. The resultant effects on the pharynx (and in one case on the right lung) are described and guidelines are laid down for the approach to and treatment of these injuries. Both patients recovered, with an acceptable cosmetic and functional result.
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Faringe/lesões , Acidentes Domésticos , Criança , Humanos , Masculino , Faringe/cirurgiaRESUMO
Intensive plasma exchange was performed with a continuous-flow centrifuge in 2 pregnant women severely immunized to the Rh(D) iso-antigen. Plasma exchange was started at 17 and 18 weeks of gestation and a total of 220 litres and 185 litres plasma was replaced with plasma protein fraction over a period of 14 and 12 weeks respectively. There was a marked lowering of the anti-D antibody concentration in one patient, and the expected increase in antibody level during pregnancy was prevented in the other. Serum IgG and IgA levels were decreased by the exchange, but the continuous hypogammaglobulinaemia had no adverse effects. The serum IgM concentration was also lowered, but plasma levels returned to normal between plasma exchange procedures. The successful outcome in both cases suggests that intensive plasma exchange may reduce fetal haemolysis and that it may be an useful adjunct to amniocentesis, intra-uterine transfusions and premature delivery in the prenatal management of haemolytic disease in newborn infants.
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Incompatibilidade de Grupos Sanguíneos/terapia , Troca Plasmática/métodos , Complicações Hematológicas na Gravidez/sangue , Sistema do Grupo Sanguíneo Rh-Hr/imunologia , Adulto , Feminino , Humanos , Recém-Nascido , Doenças do Recém-Nascido/sangue , GravidezRESUMO
A case of cardiac injury in which a missile penetrated the inferior surface of the left ventricle and lodged in the interventricular septum is described. This unusual location, plus the fact that a piece of shrapnel at high velocity quickly loses speed owing to its aerodynamic instability, becoming a low-velocity missle, possible contributed to saving the patient's life.