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Protoplasting refers to the isolation of protoplasts from plant material. These protoplasts are cells bound only by their plasma membranes following the removal of their cell walls. In grapevine research, protoplasting efforts and successes have been reported from 1985 onwards, but recent research has shown a renewed focus on grapevine-derived protoplasts, particularly due to the possibility of using protoplasts in applications such as gene-editing approaches. Grapevine species are generally considered recalcitrant to manipulation in culture and have also proven recalcitrant with regards to protoplasting and particularly in the regeneration of plants from protoplasts. This review will highlight the important milestones in grapevine protoplasting while outlining the current efforts to establish grapevine protoplasting as a routine technique. [ABSTRACT FROM AUTHOR]

The Daya Bay, Double Chooz and RENO experiments recently observed a significant distortion in their detected reactor antineutrino spectra, being at odds with the current predictions. Although such a result suggests to revisit the current reactor antineutrino spectra modeling, an alternative scenario, which could potentially explain this anomaly, is explored in this letter. Using an appropriate statistical method, a study of the Daya Bay experiment energy scale is performed. While still being in agreement with the γ calibration data and B 12 measured spectrum, it is shown that a O ( 1 % ) deviation of the energy scale reproduces the distortion observed in the Daya Bay spectrum, remaining within the quoted calibration uncertainties. Potential origins of such a deviation, which challenge the energy calibration of these detectors, are finally discussed. [ABSTRACT FROM AUTHOR]

The dagger nematode, Xiphinema index, is considered a major pest in grape growing countries. Xiphinema index is especially important because of its ability to transmit Grapevine fanleaf virus when feeding on grapevine roots. This paper provides a comprehensive and updated review of the classification, genetics and biology of Xiphinema index, and its relationship with grapevine fanleaf virus. Current control measures, as well as past and present efforts to breed resistant grapevine rootstocks, are presented. [ABSTRACT FROM AUTHOR]

nther-derived pre-embryogenic masses (PEMs) of callus, established via suspension cultures, were encapsulated to form synthetic seeds suitable for cryopreservation. The synchronised suspension culture proliferation necessitated the optimisation of plant growth regulators for different cultivars. The growth phase and density of the culture were also important as well as the exposure of cells to vitrification solution containing 0.75 M sucrose with 0.1 M CaCl and 2.0 % sodium alginate (pH 5.7). Pre-treatment of the encapsulated cells for 2 d with Nitsch and Nitsch (NN) medium containing 0.75 M sucrose solution followed by dehydration for 4 h in a laminar flow box provided maximum cell viability, which varied from 0 to 40 %. The embryo proliferation from the cryopreserved beads involved warming them and then transfer to NN medium containing glutamine (50 mg dm) and activated charcoal (2.5 %). The maximum number of embryos obtained was 31-53 per bead. Subculture into the same medium induced secondary embryogenesis, which was initiated from the meristematic region, radicle, and root cap. Proliferation and maturation of secondary embryos was faster than of primary embryos. No phenotypic variation or abnormal structures compared to the control were observed in the regenerated plantlets. [ABSTRACT FROM AUTHOR]

The annihilations of WIMPs can lead to the production of very-high energy (VHE) γ-rays in the final state. These VHE γ- rays may be detected by Imaging Atmospheric Cherenkov Telescopes (IACTs) like the H.E.S.S. instrument. We review here the search for such annihilations towards the Galactic Center and the Canis Major overdensity. Constraints on the velocity-weighted cross-sections ⟨σv⟩ of WIMPs are computed within the framework of supersymmetric and Kaluza-Klein extensions of the Standard Model of Particle Physics. [ABSTRACT FROM AUTHOR]

Rare-event search experiments located on-surface, such as short-baseline reactor neutrino experiments, are often limited by muon-induced background events. Highly efficient muon vetos are essential to reduce the detector background and to reach the sensitivity goals. We demonstrate the feasibility of deploying organic plastic scintillators at sub-Kelvin temperatures. For the NUCLEUS experiment, we developed a cryogenic muon veto equipped with wavelength shifting fibers and a silicon photo multiplier operating inside a dilution refrigerator. The achievable compactness of cryostat-internal integration is a key factor in keeping the muon rate to a minimum while maximizing coverage. The thermal and light output properties of a plastic scintillation detector were examined. We report first data on the thermal conductivity and heat capacity of the polystyrene-based scintillator UPS-923A over a wide range of temperatures extending below one Kelvin. The light output was measured down to 0.8 K and observed to increase by a factor of 1.61 ± 0.05 compared to 300 K. The development of an organic plastic scintillation muon veto operating in sub-Kelvin temperature environments opens new perspectives for rare-event searches with cryogenic detectors at sites lacking substantial overburden. [ABSTRACT FROM AUTHOR]

Coherent elastic neutrino-nucleus scattering (CE ν NS), detected for the first time more than 40 years after its prediction, represents an experimental challenge because of its signature: a single nuclear recoil with energy in the range of 10 eV to a few 10's keV on average. One of the main features of CE ν NS is its cross section, around two orders of magnitude higher compared with the inverse β decay. BASKET (Bolometers At Sub keV Energy Threshold) project aims at investigating cryogenic calorimeters for the CE ν NS detection, able to maintain the background level below the expected signature while being operated in above ground conditions in close vicinity to a nuclear reactor. The main requirements for such detectors are a low enough energy threshold of O(10 eV), and a fast signal rise time in the range of 0.1–1 ms to achieve good timing resolution and hence good mitigation of pile-up events. In this article, we report on the first tests of a prototype detector coupling a Li 2 WO 4 crystal to a magnetic metallic calorimeter (MMC) thermal sensor. [ABSTRACT FROM AUTHOR]

The NUCLEUS experiment aims at measuring the coherent elastic scattering of nuclear reactor antineutrinos off nuclei using cryogenic calorimeters. Operating at an overburden of 3 m.w.e., muon-induced backgrounds are expected to be dominant. It is therefore essential to develop an efficient muon veto, with a detection efficiency of more than 99 %. This will be realized in NUCLEUS through a compact cube assembly of plastic scintillator panels. In order to prevent a large unshielded area where the cryostat intersects the shielding arrangement without unnecessarily increasing the induced detector dead time, a novel concept has been investigated, featuring a plastic scintillator-based active muon veto operating inside the NUCLEUS cryostat at sub-Kelvin temperatures. The verification of the key physical aspects of this cryogenic muon veto detector led to the first reported measurements of organic plastic scintillators at sub-Kelvin temperatures. The functionality of the principal scintillation process of organic plastic scintillators at these temperatures has been confirmed. On the basis of these findings, a disk-shape plastic scintillator equipped with wavelength shifting fibers and a silicon photomultiplier to guide and detect the scintillation light has been developed. The NUCLEUS cryogenic muon veto will be the first of its kind to be operated at sub-Kelvin temperatures. [ABSTRACT FROM AUTHOR]

The use of High Purity Germanium detectors operated in ionization mode at cryogenic temperatures is investigated as an external background mitigation solution for bolometers used in rare-event search experiments. A simple experimental setup, running a 52-g Li 2 WO 4 bolometer sandwiched in-between two 2-cm thick High Purity Germanium cylindrical detectors in a dry cryostat, shows promising rejection to environmental gammas and atmospheric muons backgrounds. The acquired data are used together with a Monte Carlo simulation of the setup to extract the main contributions to the external backgrounds expected in an above ground experiment, such as e.g. current and future experimental efforts targeting the detection of coherent elastic neutrino-nucleus scattering at reactor facilities. Based on all these results, a 4 π coverage similar veto system achieving a O (10 keV) energy threshold is expected to achieve a ≳ 73% and a ≳ 92% rejection power for gamma-like and muon-like events, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Vagus nerve stimulation of afferents is used as an adjunctive treatment for drug-resistant epilepsy and depression. In addition, anti-inflammatory properties of vagus nerve stimulation have been reported in various experimental models of inflammation but not in colitis. These effects are thought to be mediated via peripheral release of acetylcholine from the vagus and subsequent activation of macrophages. Our aim was to evaluate in rats the anti-inflammatory effects of chronic vagus nerve stimulation on colonic inflammation. Colitis was induced by intracolonic instillation of trinitrobenzene sulfonic acid. Vagus nerve stimulation (left cervical) was performed in freely moving animals 3h per day for five consecutive days. Assessment of colonic inflammation was obtained using physiological (e.g. body weight, temperature and locomotor activity) parameters, macroscopical (area of lesions), histological, and biological parameters (e.g. myeloperoxidase activity, cytokine and cytokine-related mRNAs), both at the level of the damaged colon and the colon immediately above. A global multivariate index of colitis was then generated for a better characterization of colonic inflammation. Vagus nerve stimulation reduced the degree of body weight loss and inflammatory markers as observed above the lesion by histological score and myeloperoxidase quantification. This anti-inflammatory effect was also demonstrated by the improvement of the multivariate index of colitis. These data argue for an anti-inflammatory role of vagus nerve stimulation chronically performed in freely moving rats with colitis and provide potential therapeutic applications for patients with inflammatory bowel diseases. [Copyright &y& Elsevier]

• 3D nanostructuration of nanoporous membrane-electrodes allows a pre-concentration of mercury by passive adsorption. • Hg(II) sensors showed a good mercury recovery in mineral and ground waters. • Results in superficial waters pointed to Hg(II) instabilities when dissolved organic carbon content was superior to 3.5 mg/L. • streaming potential experiment was found efficient to fully characterize grafted charged polymer chains inside nanochannels. Poly-4-vinylpyridine grafted poly(vinylidene difluoride) (P4VP-g-PVDF) nanoporous polymer electrodes were found to be sensitive for Hg(II) analysis. The fabrication and characterization of functionalized nanoporous membrane-electrodes by FESEM and FTIR are presented. Functionalized nanopore charge state versus a large range of pH (1–10) was investigated by registering the streaming potential. This isoelectric point is achieved at the pKa of P4VP (pH = 5). Mercury adsorption at solid-liquid interface obeys a Langmuir law. A protocol for accurate Hg(II) analysis at ppb level was established. Calibration curves were performed and different real water samples (mineral water, ground water, surface water) were spiked and analyzed. The resulting sensor is intended to be integrated into existing systems or used standalone as portable devices. A first generation prototype exhibiting its own integrated potentiostat, its software and set of membrane-electrode pads is presented. [ABSTRACT FROM AUTHOR]

Detarium microcarpum is an African tree which is widely used as a folk medicine and food. A methanol extract from the leaves as well as its hexane, dichloromethane, ethyl acetate and n-butanol fractions were evaluated for their total phenolic content and radical scavenging activities. Additionally, a pre-column DPPH-HPLC assay was performed to screen and identify the compounds responsible for the antioxidant properties of the extract. Results indicated that the methanol extract contained a substantial amount of phenolic compounds with a value of 51.7 ± 0.2 mg gallic acid equivalent/g. It also exerted potent radical scavenging activities in both DPPH and ORAC assays, with respective values of 937 ± 16 and 2247 ± 63 μmol trolox equivalent/g. Its ethyl acetate and n-butanol fractions were shown to possess the highest TPC and radical scavenging activities. Pre-column DPPH-HPLC experiments led to the direct detection of five potential radical scavenging compounds which were identified as gallic acid, quercetin 3,7- O-dirhamnoside, myricetin 3- O-rhamnoside, quercetin 3- O-glucoside and quercetin 3- O-rhamnoside. All of them were confirmed to exert potent radical scavenging activities using common DPPH spectrophotometric assay. These findings revealed that D. microcarpum leaves possess potent antioxidant activity and could be recommended as a nutraceutical resource. Additionally, the identified bioactive compounds can be considered as appropriate markers for quality control. [ABSTRACT FROM AUTHOR]

Cell suspension cultures of Vitis vinifera cv. Dauphine berries were used to study the response to the vascular pathogen, Eutypa lata, in comparison with a biological control agent, Trichoderma atroviride, that was previously shown to be effective in pruning wound protection. The expression of genes coding for enzymes of the phenylpropanoid pathway and pathogenesis-related (PR) proteins was profiled over a 48-h period using quantitative reverse transcriptase PCR. The cell cultures responded to elicitors of both fungi with a hypersensitive-like response that lead to a decrease in cell viability. Similar genes were triggered by both the pathogen and biocontrol agent, but the timing patterns and magnitude of expression was dependent on the specific fungal elicitor. Culture filtrates of both fungi caused upregulation of phenylalanine ammonia-lyase ( PAL), 4-coumaroyl Co-A ligase ( CCo-A) and stilbene synthase ( STS), and a downregulation of chalcone synthase ( CHS) genes. The pathogen filtrate caused a biphasic pattern in the upregulation of PAL and STS genes which was not observed in cells treated with filtrates of the biocontrol agent. Analytical assays showed significantly higher total phenolic content and chitinolytic enzyme activity in the cell cultures treated with the T. atroviride filtrate compared to the pathogen filtrate. These results corresponded well to the higher expression of PAL and chitinase class IV genes. The response of the cell cultures to T. atroviride filtrate provides support for the notion that the wound protection by the biocontrol agent at least partially relies on the induction of grapevine resistance mechanisms. [ABSTRACT FROM AUTHOR]

The High-energy Stereoscopic System (H.E.S.S.) is an array of atmospheric Cherenkov telescopes dedicated to GeV-TeV \gamma ray astronomy. Four 12 meter diameter telescopes (CT) are currently in operation and a fifth 28 meter diameter telescope (LCT) should be completed by 2011. This will lower the system's energy threshold in stereoscopy down to \approx50 GeV. Concurrently, the LCT will also be used to detect monoscopic lower energy showers without a coincident detection on the smaller telescopes. This is made possible thanks to the higher sensitivity and the faster electronics of the LCT. But lowering the L1 trigger conditions on the LCT results in a larger number of spurious background detections the reduction of which motivates the second level trigger system of the LCT. An efficient L2 selection algorithm was designed based on intensive off line simulations of air shower images from different background events and their morphological differences as seen by the LCT. The present contribution reports on the flexible and reconfigurable hardware solution designed for the L2 trigger, and on the real-time implementation of the proposed L2 algorithm. [ABSTRACT FROM PUBLISHER]

Abstract: HESS is an array of atmospheric Cherenkov telescopes dedicated to GeV–TeV γ-ray astronomy. The original array has been in operation since the beginning of 2004. It is composed of four 12-m diameter telescopes. The installation of a fifth 28-m diameter telescope is being completed. This telescope will operate both in stereoscopic mode and in monoscopic mode i.e. without a coincident detection on the smaller telescopes. A second-level trigger system is needed to suppress spurious triggers of the 28-m telescope when operated in monoscopic mode. This paper gives the motivation and principle of the second-level trigger. The principle of operation is illustrated by an example algorithm. The hardware implementation of the second level trigger system of HESS phase 2 is described and its expected performances are then evaluated. [Copyright &y& Elsevier]

Background and Aims: Carotenoids and chlorophylls perform a number of essential roles in plants making their accurate quantification important to a variety of studies. We aimed to develop an extraction protocol to accurately determine the photosynthetic pigments in grapevine leaf and berry tissue, specifically focusing on limiting the degradation of these pigments. Methods and Results: An extraction protocol for grapevine leaf and berry tissue was systematically optimised by identifying a number of critical parameters. Extracted pigments were analysed using Reversed Phase-High Performance Liquid Chromatography (RP-HPLC). Specific parameters that were optimised included avoiding freeze-drying the material; the volume of acetone and the time required to extract all the pigments from the tissue; the addition of 0.1% (v/v) N-ethyldiisopropylamine to berry extracts to minimise pigment degradation during the extraction procedure; and avoiding concentration of the extracts that otherwise resulted in differential degradation of pigments. Additionally, the method of extraction and normalisation with an internal standard was adapted and improved for accuracy. The optimised protocol was validated using authentic standards and its utility shown by analysing the pigment content of berries and leaves at different growth stages. Conclusions: A method has been developed that is able to extract and accurately quantify, by means of HPLC profiling, the levels of photosynthetic pigments from grape berries and leaves. The method avoided any degradation of the pigments during the extraction and was applicable to both berries and leaves in different stages of growth and development, indicating its general usefulness to vegetative and reproductive organs, even if their metabolic states are very different. Significance of Study: The divergence of methods used for photosynthetic pigment analysis in plants, each with specific advantages and disadvantages were considered and used to optimise a number of parameters in a single method that proved to be applicable to plant organs in different developmental stages. The method is fast, applicable to vegetative and reproductive grapevine tissues, avoids degradation of pigments and ensures maximum accuracy when quantifying these important pigments. [ABSTRACT FROM AUTHOR]