407 research outputs found

    Micro-CT constitutes a valuable tool in assessing the impact of cordon constriction on the vascular morphology of grapevines

    Get PDF
    The impact of permanent cordon training systems on the vasculature of grapevines has to date, not been investigated in depth. This study used optical microscopy (stereo microscope) and X-ray microtomography (micro-CT) to quantify the morphological properties of the xylem conduits of cane samples collected from the distal region of cordons, which had been established using four different training techniques. These treatments included one system where the cordon was wrapped very tightly around the cordon wire, a practice that is common in Australia and some other countries. The study also used micro-CT to observe the cordons directly, providing clear insight into the effects of the training methods on the localised structure of the cordons themselves. While the cordons in this study were only four years old at the time of their scanning and 3D reconstruction, significant differences were found between the different training methods. At one of the two trial sites, cordons which were wrapped tightly around the cordon wire had a significantly lower xylem conduit volume in relation to total cordon volume than those which had been woven through a plastic clip system centred between parallel cordon wires. The xylem conduits of woven cordons, in turn, had a lower volume than those which had been trained on top of the cordon wire and secured in place with plastic ties. Cordons which had been wrapped tightly around the cordon wire also had significantly thinner vessels and fewer connections per unit volume between vessels than other treatments at this site, as well as a lower theoretical specific hydraulic conductivity (Ks). No definitive patterns of differences between treatments were observed in the morphological properties of cane samples, either by stereo microscope or micro-CT. The results of this study suggest that the choice of cordon training method may have a notable impact on the capacity of the xylem for normal hydraulic function. Training methods which constrict the vasculature of the cordon, in particular tightly wrapping the cordon around the cordon wire, may have long-term negative outcomes on cordon health and productivity.Patrick O, Brien, Roberta De Bei, and Cassandra Collin

    In vitro and in vivo inhibition of breast cancer cell growth by targeting the Hedgehog/GLI pathway with SMO (GDC-0449) or GLI (GANT-61) inhibitors.

    Get PDF
    Aberrant Hedgehog (Hh)/glioma-associated oncogene (GLI) signaling has been implicated in cancer progression. Here, we analyzed GLI1, Sonic Hedgehog (Shh) and NF-κB expression in 51 breast cancer (ductal carcinoma) tissues using immunohistochemistry. We found a positive correlation between nuclear GLI1 expression and tumor grade in ductal carcinoma cases. Cytoplasmic Shh staining significantly correlated with a lower tumor grade. Next, the in vitro effects of two Hh signaling pathway inhibitors on breast cancer cell lines were evaluated using the Smoothened (SMO) antagonist GDC-0449 and the direct GLI1 inhibitor GANT-61. GDC-0449 and GANT-61 exhibited the following effects: a) inhibited breast cancer cell survival; b) induced apoptosis; c) inhibited Hh pathway activity by decreasing the mRNA expression levels of GLI1 and Ptch and inhibiting the nuclear translocation of GLI1; d) increased/decreased EGFR and ErbB2 protein expression, reduced p21- Ras and ERK1/ERK2 MAPK activities and inhibited AKT activation; and e) decreased the nuclear translocation of NF-κB. However, GANT-61 exerted these effects more effectively than GDC-0449. The in vivo antitumor activities of GDC-0449 and GANT- 61 were analyzed in BALB/c mice that were subcutaneously inoculated with mouse breast cancer (TUBO) cells. GDC-0449 and GANT-61 suppressed tumor growth of TUBO cells in BALB/c mice to different extents. These findings suggest that targeting the Hh pathway using antagonists that act downstream of SMO is a more efficient strategy than using antagonists that act upstream of SMO for interrupting Hh signaling in breast cancer

    Infra-Red thermal image analysis for grapevines

    Get PDF
    Trabajo presentado en el 18th International Symposium of the Group of International Experts of vitivinicultural Systems for CoOperation (GIESCO 2013), celebrado en Oporto del 7 al 11 de julio de 2013.-- Número fuera de serie.Infrared thermal images (IRTI) have been used for grapevine research since the early 90’s. Even though its promising results in the assessment of canopy stomatal conductance and plant water status, from the beginning and recent research publications, it has not been fully applied on a commercial scale yet. It is believed that the bottleneck for this technology is the lack of reliable automation tools for IRTI analysis. Accurate and reliable automation technique s will allow the use of this technique to assess the spatial variability of physiological processes within the canopy using infrared cameras mounted on moving vehicles, drones, octocopters or robots. Automated analysis systems are requirement of The Vineyard of The Future initiative, which is an international effort to establis h fully monitored vineyards in the most prominent viticultural and winemaking areas in the world. In this work, a semi-automated IRTI analyses performed using a code written in MATLAB® for estimate dry and wet references excluding non-leaf temperatures was compared with evaporimeter (EvapoSensor, Skye Instruments Ltd, Powys, UK) measurements used to provide dry and wet references from IRTIs. Results obtained from this research (grapevines cv. Tempranillo) showed good and statistically significant correlations between temperatur e references obtained from IRTI analysis and measured values. This work constitutes one additional step forward to the implementation of thermal imaging as an automated routine technique for physiological vineyard assess ment from proximal sensing and unmanned aerial vehicles (UAV) platforms.The research leading to this report was supported by the Spanish project “STRESSIMAGING HPRN-CT-2002-00254” and Chilean projects CONICYT (Nº 79090035) and Programa de Investigación sobre Adaptación de la Agricultura al Cambio Climático - PIEI (Universidad de Talca).Peer Reviewe

    Combined treatment with inhibitors of ErbB Receptors and Hh signaling pathways is more effective than single treatment in reducing the growth of malignant mesothelioma both in vitro and in vivo

    Get PDF
    Malignant mesothelioma (MM) is a rare orphan aggressive neoplasia with low survival rates. Among the other signaling pathways, ErbB receptors and Hh signaling are deregulated in MM. Thus, molecules involved in these signaling pathways could be used for targeted therapy approaches. The aim of this study was to evaluate the effects of inhibitors of Hh- (GANT-61) and ErbB receptors (Afatinib)-mediated signaling pathways, when used alone or in combination, on growth, cell cycle, cell death and autophagy, modulation of molecules involved in transduction pathways, in three human MM cell lines of different histotypes. The efficacy of the combined treatment was also evaluated in a murine epithelioid MM cell line both in vitro and in vivo. This study demonstrated that combined treatment with two inhibitors counteracting the activation of two different signaling pathways involved in neoplastic transformation and progression, such as those activated by ErbB and Hh signaling, is more effective than the single treatments in reducing MM growth in vitro and in vivo. This study may have clinical implications for the development of targeted therapy approaches for MM

    Classification of smoke contaminated Cabernet Sauvignon berries and leaves based on chemical fingerprinting and machine learning algorithms

    Get PDF
    Wildfires are an increasing problem worldwide, with their number and intensity predicted to rise due to climate change. When fires occur close to vineyards, this can result in grapevine smoke contamination and, subsequently, the development of smoke taint in wine. Currently, there are no in-field detection systems that growers can use to assess whether their grapevines have been contaminated by smoke. This study evaluated the use of near-infrared (NIR) spectroscopy as a chemical fingerprinting tool, coupled with machine learning, to create a rapid, non-destructive in-field detection system for assessing grapevine smoke contamination. Two artificial neural network models were developed using grapevine leaf spectra (Model 1) and grape spectra (Model 2) as inputs, and smoke treatments as targets. Both models displayed high overall accuracies in classifying the spectral readings according to the smoking treatments (Model 1: 98.00%; Model 2: 97.40%). Ultraviolet to visible spectroscopy was also used to assess the physiological performance and senescence of leaves, and the degree of ripening and anthocyanin content of grapes. The results showed that chemical fingerprinting and machine learning might offer a rapid, in-field detection system for grapevine smoke contamination that will enable growers to make timely decisions following a bushfire event, e.g., avoiding harvest of heavily contaminated grapes for winemaking or assisting with a sample collection of grapes for chemical analysis of smoke taint markers

    Ozone response to emission changes: a modeling study during the MCMA-2006/MILAGRO Campaign

    Get PDF
    The sensitivity of ozone production to precursor emissions was investigated under five different meteorological conditions in the Mexico City Metropolitan Area (MCMA) during the MCMA-2006/MILAGRO field campaign using the gridded photochemical model CAMx driven by observation-nudged WRF meteorology. Precursor emissions were constrained by the comprehensive data from the field campaign and the routine ambient air quality monitoring network. Simulated plume mixing and transport were examined by comparing with measurements from the G-1 aircraft during the campaign. The observed concentrations of ozone precursors and ozone were reasonably well reproduced by the model. The effects of reducing precursor emissions on urban ozone production were performed for three representative emission control scenarios. A 50% reduction in VOC emissions led to 7 to 22 ppb decrease in daily maximum ozone concentrations, while a 50% reduction in NOx [NO subscript x] emissions leads to 4 to 21 ppb increase, and 50% reductions in both NOx [NO subscript x] and VOC emission decrease the daily maximum ozone concentrations up to 10 ppb. These results along with a chemical indicator analysis using the chemical production ratios of H2O2 [H subscript 2 O subscript 2] to HNO3 [HNO subscript 3] demonstrate that the MCMA urban core region is VOC-limited for all meteorological episodes, which is consistent with the results from MCMA-2003 field campaign; however the degree of the VOC-sensitivity is higher during MCMA-2006 due to lower VOCs, lower VOC reactivity and moderately higher NOx [NO subscript x] emissions. Ozone formation in the surrounding mountain/rural area is mostly NOx-limited [NO subscript x - limited], but can be VOC-limited, and the range of the NOx-limited [NO subscript x - limited] or VOC-limited areas depends on meteorology.United States. Dept. of Energy. Office of Biological and Environmental Research. Atmospheric Science Program (DE-FG02-05ER63980)National Science Foundation (U.S.). Atmospheric Chemistry Program (ATM-0528227)National Science Foundation (U.S.). Atmospheric Chemistry Program (ATM-810931)Mexico. Comisión Ambiental MetropolitanaMolina Center for Energy and the Environmen

    Effects of canopy management practices on grapevine bud fruitfulness

    Get PDF
    Published: 26 May 2020Background and aims: Bud fruitfulness is a key component of grapevine reproductive performance as it determines crop production for the following growing season. While canopy microclimate can impact bud fruitfulness, the effects of canopy management practices on bud fruitfulness are not well known. The objective of this study was to investigate the effects of common canopy management practices on bud fruitfulness and the relationships with shoot growth capacity, bud microclimate and bud carbohydrate level. Methods and results: Different canopy management practices, (shoot thinning, bunch thinning, leaf removal and lighter pruning) were applied to Semillon and Shiraz grapevines (Vitis vinifera L.). Light interception at the bud zone was measured after canopy management practices were applied. Bud fruitfulness at dormancy was assessed using bud dissection analysis. The number and size of inflorescence primordia, and the incidence of primary bud necrosis were recorded. The results were correlated with measurements of shoot growth capacity and carbohydrate content of buds and canes. Conclusions: Bud fruitfulness was mostly influenced by bud light interception, while the size of inflorescence primordia was positively correlated with shoot growth capacity and the carbohydrate level of buds. By altering canopy microclimate, canopy management practices can be used to manipulate bud fruitfulness and potentially bunch size. Significance and impact of the study: This study provides novel information on the impact of canopy management on grapevine bud fruitfulness and the size of inflorescence primordia. These findings can be used to make more informed vineyard management decisions for better yield control.Xiaoyi Wang, Stephen Lesefko, Roberta De Bei, Sigfredo Fuentes and Cassandra Collin

    Wine Terroir and the Soil Bacteria: An Amplicon Sequencing-Based Assessment of the Barossa Valley and Its Sub-Regions

    Get PDF
    A wines’ terroir, represented as wine traits with regional distinctiveness, is a reflection of both the biophysical and human-driven conditions in which the grapes were grown and wine made. Soil is an important factor contributing to the uniqueness of a wine produced by vines grown in specific conditions. Here, we evaluated the impact of environmental variables on the soil bacteria of 22 Barossa Valley vineyard sites based on the 16S rRNA gene hypervariable region 4. In this study, we report that both dispersal isolation by geographic distance and environmental heterogeneity (soil plant-available P content, elevation, rainfall, temperature, spacing between row and spacing between vine) contribute to microbial community dissimilarity between vineyards. Vineyards located in cooler and wetter regions showed lower beta diversity and a higher ratio of dominant taxa. Differences in soil bacterial community composition were significantly associated with differences in fruit and wine composition. Our results suggest that environmental factors affecting wine terroir, may be mediated by changes in microbial structure, thus providing a basic understanding of how growing conditions affect interactions between plants and their soil bacteria

    Optical one-way quantum computing with a simulated valence-bond solid

    Full text link
    One-way quantum computation proceeds by sequentially measuring individual spins (qubits) in an entangled many-spin resource state. It remains a challenge, however, to efficiently produce such resource states. Is it possible to reduce the task of generating these states to simply cooling a quantum many-body system to its ground state? Cluster states, the canonical resource for one-way quantum computing, do not naturally occur as ground states of physical systems. This led to a significant effort to identify alternative resource states that appear as ground states in spin lattices. An appealing candidate is a valence-bond-solid state described by Affleck, Kennedy, Lieb, and Tasaki (AKLT). It is the unique, gapped ground state for a two-body Hamiltonian on a spin-1 chain, and can be used as a resource for one-way quantum computing. Here, we experimentally generate a photonic AKLT state and use it to implement single-qubit quantum logic gates.Comment: 11 pages, 4 figures, 8 tables - added one referenc

    Non-invasive tools to detect smoke contamination in grapevine canopies, berries and wine: a remote sensing and machine learning modeling approach

    Get PDF
    Bushfires are becoming more frequent and intensive due to changing climate. Those that occur close to vineyards can cause smoke contamination of grapevines and grapes, which can affect wines, producing smoke-taint. At present, there are no available practical in-field tools available for detection of smoke contamination or taint in berries. This research proposes a non-invasive/in-field detection system for smoke contamination in grapevine canopies based on predictable changes in stomatal conductance patterns based on infrared thermal image analysis and machine learning modeling based on pattern recognition. A second model was also proposed to quantify levels of smoke-taint related compounds as targets in berries and wines using near-infrared spectroscopy (NIR) as inputs for machine learning fitting modeling. Results showed that the pattern recognition model to detect smoke contamination from canopies had 96% accuracy. The second model to predict smoke taint compounds in berries and wine fit the NIR data with a correlation coefficient (R) of 0.97 and with no indication of overfitting. These methods can offer grape growers quick, affordable, accurate, non-destructive in-field screening tools to assist in vineyard management practices to minimize smoke taint in wines with in-field applications using smartphones and unmanned aerial systems (UAS).Sigfredo Fuentes, Eden Jane Tongson, Roberta De Bei, Claudia Gonzalez Viejo, Renata Ristic, Stephen Tyerman, and Kerry Wilkinso
    corecore