52 research outputs found
The localisation of acids, sugars, potassium and calcium in developing grape berries
Grape berries (Vitis vinifera cv. Chardonnay) were divided into four concentric zones in order to follow the developmental changes in the concentrations of malate, tartrate, glucose, fructose, potassium and calcium within the skin and the fruit flesh. Green berries showed a definite malate gradient, increasing in concentration from the skin towards the seeds; tartaric acid, on the other hand, was highest in concentration at the periphery and lowest in the berry center. With progressing maturity, the ratio between the tartrate concentration in the skin and the corresponding values in the berry core decreased, whereas the reverse was true for malate. In the ripe berry an acid gradient could also be found in the axial direction, decreasing from the pedicel towards the stylar scar. Before the onset of ripening, the highest glucose and fructose concentrations were observed in the skin and the berry center. The accumulation of these sugars in the pulp began without any apparent lag phase at a rate of about 2 mg/ berry · d. After veraison, the highest concentrations were found in the fruit core and the tissue below the peripheral vascular bundles. Both potassium and calcium were mainly localized near the peripheral and central vascular bundles. The potassium content increased during the entire period of berry development at a constant rate of 0.04 mg/berry · d, whereas calcium accumulation stopped about 30 d after anthesis. At this time, the calcium content was approximately 0.1 mg/berry
Stable Longitudinal Quality of Life in the SERVE Trial Among Adults With Transposition of the Great Arteries and a Systemic Right Ventricle.
Adults with a transposition anatomy and a systemic right ventricle (RV) face long-term complications that may impact their quality of life (QoL). Few data are available regarding the QoL in this patient group and its evolution over time.
This study was performed in the SERVE trial's (identifier: NCT03049540) prospective cohort of patients (n = 100) with congenitally corrected transposition of the great arteries (TGA) or dextro-TGA after the atrial switch procedure and a longitudinal follow-up of 3 years. We aimed to describe the longitudinal QoL levels and their predictors. QoL was assessed using the Linear Analog Scale. QoL parameters were collected at baseline, after 12 months, and after 36 months, together with clinical parameters and a questionnaire assessing general self-efficacy (GSE).
The mean QoL on the Linear Analog Scale was 79.1 ± 13.6 at baseline, 75.5 ± 14.8 at 1 year, and 79.2 ± 13.6 at 3-year follow-up (P = 0.900). No significant differences in QoL were observed between congenitally corrected TGA or dextro-TGA patients. Cardiopulmonary exercise testing maximum work rate and maximum oxygen uptake, New York Heart Association class, end-diastolic RV volumes, N-terminal pro-B-type natriuretic peptide concentration, and GSE showed significant correlations with QoL levels. Multivariable regression analysis identified GSE value and New York Heart Association class (r <sup>2</sup> = 0.283, P < 0.001) as independent predictors of QoL at baseline.
Patients with a systemic RV reported a stable good QoL during 3 years of follow-up. Exercise capacity and self-efficacy were the only independent predictors of QoL.
NCT03049540
Decreased clinical performance in TGA-ASO patients after RVOT interventions; a multicenter European collaboration.
In patients with transposition of the great arteries and an arterial switch operation (TGA-ASO) right ventricular outflow tract (RVOT) obstruction is a common complication requiring one or more RVOT interventions.
We aimed to assess cardiopulmonary exercise capacity and right ventricular function in patients stratified for type of RVOT intervention.
TGA-ASO patients (≥16 years) were stratified by type of RVOT intervention. The following outcome parameters were included: predicted (%) peak oxygen uptake (peak VO2), tricuspid annular plane systolic excursion (TAPSE), tricuspid Lateral Annular Systolic Velocity (TV S'), right ventricle (RV)-arterial coupling (defined as TAPSE/RV systolic pressure ratio), and N-terminal proBNP (NT-proBNP).
447 TGA patients with a mean age of 25.0 (interquartile range (IQR) 21-29) years were included. Patients without previous RVOT intervention (n = 338, 76%) had a significantly higher predicted peak VO2 (78.0 ± 17.4%) compared to patients with single approach catheter-based RVOT intervention (73.7 ± 12.7%), single approach surgical RVOT intervention (73.8 ± 28.1%), and patients with multiple approach RVOT intervention (66.2 ± 14.0%, p = 0.021). RV-arterial coupling was found to be significantly lower in patients with prior catheter-based and/or surgical RVOT intervention compared to patients without any RVOT intervention (p = 0.029).
TGA patients after a successful arterial switch repair have a decreased exercise capacity. A considerable amount of TGA patients with either catheter or surgical RVOT intervention perform significantly worse compared to patients without RVOT interventions
Bounding global aerosol radiative forcing of climate change
Aerosols interact with radiation and clouds. Substantial progress made over the past 40 years in observing, understanding, and modeling these processes helped quantify the imbalance in the Earth's radiation budget caused by anthropogenic aerosols, called aerosol radiative forcing, but uncertainties remain large. This review provides a new range of aerosol radiative forcing over the industrial era based on multiple, traceable, and arguable lines of evidence, including modeling approaches, theoretical considerations, and observations. Improved understanding of aerosol absorption and the causes of trends in surface radiative fluxes constrain the forcing from aerosol-radiation interactions. A robust theoretical foundation and convincing evidence constrain the forcing caused by aerosol-driven increases in liquid cloud droplet number concentration. However, the influence of anthropogenic aerosols on cloud liquid water content and cloud fraction is less clear, and the influence on mixed-phase and ice clouds remains poorly constrained. Observed changes in surface temperature and radiative fluxes provide additional constraints. These multiple lines of evidence lead to a 68% confidence interval for the total aerosol effective radiative forcing of -1.6 to -0.6 W m−2, or -2.0 to -0.4 W m−2 with a 90% likelihood. Those intervals are of similar width to the last Intergovernmental Panel on Climate Change assessment but shifted toward more negative values. The uncertainty will narrow in the future by continuing to critically combine multiple lines of evidence, especially those addressing industrial-era changes in aerosol sources and aerosol effects on liquid cloud amount and on ice clouds
Isoprene nitrates drive new particle formation in Amazon’s upper troposphere
New particle formation (NPF) in the tropical upper troposphere is a globally important source of atmospheric aerosols1-4. It is known to occur over the Amazon basin, but the nucleation mechanism and chemical precursors have yet to be identified2. Here we present comprehensive in situ aircraft measurements showing that extremely low-volatile oxidation products of isoprene, particularly certain organonitrates, drive NPF in the Amazonian upper troposphere. The organonitrates originate from OH-initiated oxidation of isoprene from forest emissions in the presence of nitrogen oxides from lightning. Nucleation bursts start about 2 h after sunrise in the outflow of nocturnal deep convection, producing high aerosol concentrations of more than 50,000 particles cm-3. We report measurements of characteristic diurnal cycles of precursor gases and particles. Our observations show that the interplay between biogenic isoprene, deep tropical convection with associated lightning, oxidation photochemistry and the low ambient temperature uniquely promotes NPF. The particles grow over time, undergo long-range transport and descend through subsidence to the lower troposphere, in which they can serve as cloud condensation nuclei (CCN) that influence the Earth's hydrological cycle, radiation budget and climate1,4-8
Berry Flesh and Skin Ripening Features in Vitis vinifera as Assessed by Transcriptional Profiling
Background
Ripening of fleshy fruit is a complex developmental process involving the differentiation of tissues with separate functions. During grapevine berry ripening important processes contributing to table and wine grape quality take place, some of them flesh- or skin-specific. In this study, transcriptional profiles throughout flesh and skin ripening were followed during two different seasons in a table grape cultivar ‘Muscat Hamburg’ to determine tissue-specific as well as common developmental programs.
Methodology/Principal Findings
Using an updated GrapeGen Affymetrix GeneChip® annotation based on grapevine 12×v1 gene predictions, 2188 differentially accumulated transcripts between flesh and skin and 2839 transcripts differentially accumulated throughout ripening in the same manner in both tissues were identified. Transcriptional profiles were dominated by changes at the beginning of veraison which affect both pericarp tissues, although frequently delayed or with lower intensity in the skin than in the flesh. Functional enrichment analysis identified the decay on biosynthetic processes, photosynthesis and transport as a major part of the program delayed in the skin. In addition, a higher number of functional categories, including several related to macromolecule transport and phenylpropanoid and lipid biosynthesis, were over-represented in transcripts accumulated to higher levels in the skin. Functional enrichment also indicated auxin, gibberellins and bHLH transcription factors to take part in the regulation of pre-veraison processes in the pericarp, whereas WRKY and C2H2 family transcription factors seems to more specifically participate in the regulation of skin and flesh ripening, respectively.
Conclusions/Significance
A transcriptomic analysis indicates that a large part of the ripening program is shared by both pericarp tissues despite some components are delayed in the skin. In addition, important tissue differences are present from early stages prior to the ripening onset including tissue-specific regulators. Altogether, these findings provide key elements to understand berry ripening and its differential regulation in flesh and skin.This study was financially supported by GrapeGen Project funded by Genoma España within a collaborative agreement with Genome Canada. The authors also thank The Ministerio de Ciencia e Innovacion for project BIO2008-03892 and a bilateral collaborative grant with Argentina (AR2009-0021). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewe
Parâmetros fitotécnicos e condições microclimáticas para videira vinífera conduzida sob dupla poda sequencial
A qualidade do vinho depende da qualidade da uva produzida. As condições microclimáticas incidentes no período de crescimento e desenvolvimento da videira, especialmente na fase do estabelecimento do fruto até a colheita, afetam a qualidade do fruto. A dinâmica da água no solo tem papel importante sobre a qualidade do mosto produzido à vinificação. Em São Paulo, nas bacias de maior concentração atual da vitivinicultura ocorre um período chuvoso que se estende de novembro a fevereiro, que alcança grande parte das variedades da região em fase de crescimento e maturação da baga, o que afeta negativamente a qualidade da uva e do vinho, na maioria das safras. Por outro lado, nas mesmas regiões ocorre um período mais favorável, que é o outono/inverno com potencial de soma térmica promissor para o crescimento da videira e com incidência de um longo período de baixa pluviometria, que vai de abril a outubro. Um experimento foi conduzido, objetivando estudar o cultivo da videira nas duas estações microclimáticas descritas. Avaliou-se a composição físico-química do fruto e a condições microclimáticas para maturação da baga da videira, de 2008 a 2010. Os resultados mostraram que as variedades de videira estudas desenvolveram maior potencial de qualidade da baga, quando cultivada no período de outono-inverno, sendo o efeito mais marcante sobre Vitis vinifera.The wine quality depends on the quality grapes produced. Actual micrometeorological conditions occurring in the time frame of grapevine growth and development will impact berry quality, especially from berry set to the harvest. Soil-water dynamics plays an important role on the quality grape must achieved at the vinification. In the São Paulo State (Brasil) in the regions of greatest clustering of vintners, there is a marked rainy time-frame from November to February, which matches with the vine time-cycle when the majority of grape varieties are in the berry set to berry maturation bracket, which negatively affects the grape and wine quality in most of the harvests. In contrast, for the same region there is more favorable condition in the autumn/winter time, which has a promise heat summation for proper grape growing, characterized by a long time-frame of low pluviometric rate (April to October). An experiment was conducted aiming at study the cultivation o grapevines in both described ''climatic windows''�. Physico-chemical composition of and microclimatic conditions for berry maturation during 2008 to 2010 were analysed. Results showed that the studied grape varieties developed better berry quality potential when cultivated in the autumn/winter time and this effect was more pronounced for Vitis vinifera
Maturação dos cachos da videira 'Rubi' quando submetida a diferentes épocas de anelamento do tronco
Structural studies of glycoprotein sorting and processing complexes in the early secretory pathway [Elektronisk resurs]
The secretory pathway of a eukaryotic cell exerts a stringently regulated quality control system for the correct folding and transport of newly synthesised proteins and their subsequent transfer to their final destinations. While this pathway has been mostly studied in yeast, it has become increasingly clear that aberrations in its function are the main causes of a range of human disorders, and we are still in the process of gathering knowledge of the underlying molecular structures and mechanisms of the disease-causing agents in order to fully understand their impact. ERGIC-53, Erv41p and Ktr4p are all membrane anchored proteins involved in the transport or processing of glycoproteins, and form the main focus of this thesis. We have used X-ray crystallography and small-angle X-ray scattering, together with complementary biophysical and biochemical methods, to provide detailed descriptions of these proteins. The human glycoprotein transporter ERGIC-53 is responsible for the export of specific cargo proteins, which it binds in the endoplasmic reticulum (ER) and releases in the ER-Golgi intermediate compartment whilst cycling between the two organelles. Association of ERGIC-53 with the co-transporter MCFD2 is required for the transport of a subset of cargo proteins. ERGIC-53 is only able exert its function when present within the cell as a hexamer, but the details regulating its oligomeric state are still debated, and the structure of the hexameric protein remains unknown. We show that the oligomerisation of ERGIC-53 is independent of disulfide-bond formation and, based on small-angle X-ray scattering experiments, propose two alternative shapes describing the structure of the soluble lumenal part of the protein in its hexameric state. Erv41p is a glycoprotein transporter found in complex with its homologue Erv46p in yeast, and, similarly to ERGIC-53, the complex governs the export of cargo proteins from the ER to the Golgi apparatus, as well as the retrieval of escaped proteins back towards the ER. We have determined the structure of the soluble domain of Erv41p by X-ray crystallography, and show that the protein is comprised of a twisted β-sandwich. With almost the entirety of the concave face of Erv41p being negatively charged, this could be the site of interaction with its cargo or another interaction partner. One cargo protein that has recently been revealed to be transported by the Erv41p/Erv46p- complex is Ktr4p, a protein localised to the Golgi apparatus. Ktr4p is a member of a protein family associated with glycoprotein processing. The structures of the Ktr4p apo-protein and its complex with GDP were determined by X-ray crystallography and show that the protein is comprised of a central β-sheet surrounded by α-helices, and that it belongs to the GT-A fold class of glycosyltransferases In addition, we have biochemically characterised the protein's function and show that it indeed possesses mannosyltransferase activity
Delineation of Microdefects in Silicon Substrates by Chromium-Free Preferential Etching Solutions and Laser Scattering Tomography
Chromium-free preferential etching techniques in combination with light optical microscopy were compared with the non-destructive Laser Scattering Tomography (LST) for the evaluation of crystal defect densities in Czochralski substrates grown under different conditions. Dichromate containing etching solutions (original Secco etch and dilute Secco etch) were included into the study as reference. The chromium-free etching solutions with high etch rates comprised mixtures of nitric, hydrofluoric and acetic acid with water (JEITA 1, MEMC). Those with low etch rates consisted of mixtures of nitric and acetic or propanoic acid with hydrogen peroxide which form peracetic or perpropanoic acid (Organic Peracid Etches). OPE solutions provide improved discrimination of different types of defects and work also on highly doped substrates. As a general result, it turned out that the defect densities determined by the preferential etching solutions applied were significantly higher than those evaluated by LST. Relatively close to the LST defect densities are those determined by original Secco etch for larger etch pits.</jats:p
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