21 research outputs found
Reproduction of Pratylenchus penetrans on various rotation crops in Quebec
La reproduction du nématode des lésions racinaires Pratylenchus penetrans a été évaluée en serre sur 12 cultures de rotation. La moutarde brune (Brassica juncea) a été la meilleure plante hôte et a augmenté de 17,2 fois la population initiale. Le soja (Glycine max), le millet japonais (Echinochloa frumentacea), le colza (B. napus), le sarrasin (Fagopyrum esculentum), la moutarde blanche (B. hirta), et le raygrass vivace (Lolium perenne) ont été également très efficaces à multiplier le nématode et n'étaient pas significativement différents du seigle (Secale cereale), une plante hôte standard favorable. Le millet d'Italie (Setaria italica), l'avoine (Avena sativa), le maïs (Zea mays), et le brome des prés (Bromus inermis) ont accru respectivement de 5,8, 5,7, 4,5 et 3,2 fois la population initiale mais de façon significativement moindre que le seigle. Le millet perlé fourrager (Pennisetum glaucum) a présenté le plus faible taux de multiplication, soit 0,4. Ces résultats nous indiquent que les cultures de rotation couramment recommandées sont favorables à l'accroissement des populations du P. penetrans dans le sol à l'exception du millet perlé fourrager. Cette culture annuelle a un bon potentiel comme culture de rotation dans la répression des populations du nématode des lésions racinaires au Québec.The reproduction of the root-lesion nematode Pratylenchus penetrans was assessed on 12 rotation crops under greenhouse conditions. Brown mustard (Brassica juncea) was the best host and increased the initial population by 17.2 times. Soybean (Glycine max), Japanese millet (Echinochloa frumentacea), rape (B. napus), buckwheat (Fagopyrum esculentum), white mustard (B. hirta), and perennial ryegrass (Lolium perenne) were also very efficient in multiplying the nematode and were not significantly different from rye (Secale cereale), a standard host crop. Foxtail millet (Setaria italica), oats (Avena sativa), corn (Zea mays), and bromegrass (Bromus inermis) increased the initial population by 5.8, 5.7, 4.5, and 3.2 times respectively, but significantly less than rye. Forage pearl millet (Pennisetum glaucum) was the poorest host with a reproduction rate of 0.4. These results indicate that most commonly recommended rotation crops are suitable for the build up of P. penetrans populations in the soil with the exception of forage pearl millet. This annual crop has a great potential as a rotation crop for controlling the root-lesion nematode in Quebec
Survey of plant-parasitic and entomopathogenic nematodes in vineyards of Quebec
Un inventaire des nématodes phytoparasites et entomopathogènes présents dans des vignobles du Québec a été réalisé dans les régions de l’Estrie et de la Montérégie, les deux principales régions productrices de vignes. Des échantillons de sol provenant de 13 vignobles ont été analysés pour la présence de nématodes phytoparasites et entomopathogènes. Six genres de nématodes phytoparasites ont été observés. Les genres les plus fréquemment retrouvés étaient Pratylenchus et Paratylenchus, lesquels ont été observés dans 85 % des échantillons de sol. Aucun spécimen du genre Xiphinema n’a été retrouvé dans les vignobles. La présence de nématodes entomopathogènes fut notée dans 85 % des vignobles échantillonnés. Des nématodes entomopathogènes de la famille des Steinernematidae ont été observés dans 11 vignobles et des Heterorhabditidae dans un seul vignoble. Tous les isolats de Steinermatidae ont été identifiés comme étant de l’espèce Steinernema carpocapsae.A survey of plant-parasitic and entomopathogenic nematodes associated with vineyards was undertaken in the Estrie and Montérégie regions, the two major grapevine-producing areas in Quebec. Soil samples from 13 sampled vineyards were analyzed for the occurrence of plant-parasitic and entomopathogenic nematodes. Six genera of plant-parasitic nematodes were observed. The most commonly encountered plant-parasitic nematode genera were Pratylenchus and Paratylenchus, both occurring in 85% of sampled vineyards. No Xiphinema sp. were observed in surveyed vineyards. Entomopathogenic nematodes were recovered from 85% of the samples. Heterorhabditid and steinernematid nematodes were isolated from one and 11 vineyards respectively. Steinernematid isolates were identified as Steinernema carpocapsae
Cellular automaton decoders of topological quantum memories in the fault tolerant setting
Active error decoding and correction of topological quantum codes—in particular the toric code—remains one of the most viable routes to large scale quantum information processing. In contrast, passive error correction relies on the natural physical dynamics of a system to protect encoded quantum information. However, the search is ongoing for a completely satisfactory passive scheme applicable to locally interacting two-dimensional systems. Here, we investigate dynamical decoders that provide passive error correction by embedding the decoding process into local dynamics. We propose a specific discrete time cellular-automaton decoder in the fault tolerant setting and provide numerical evidence showing that the logical qubit has a survival time extended by several orders of magnitude over that of a bare unencoded qubit. We stress that (asynchronous) dynamical decoding gives rise to a Markovian dissipative process. We hence equate cellular-automaton decoding to a fully dissipative topological quantum memory, which removes errors continuously. In this sense, uncontrolled and unwanted local noise can be corrected for by a controlled local dissipative process. We analyze the required resources, commenting on additional polylogarithmic factors beyond those incurred by an ideal constant resource dynamical decoder
Blueprint for a Scalable Photonic Fault-Tolerant Quantum Computer
Photonics is the platform of choice to build a modular, easy-to-network
quantum computer operating at room temperature. However, no concrete
architecture has been presented so far that exploits both the advantages of
qubits encoded into states of light and the modern tools for their generation.
Here we propose such a design for a scalable and fault-tolerant photonic
quantum computer informed by the latest developments in theory and technology.
Central to our architecture is the generation and manipulation of
three-dimensional hybrid resource states comprising both bosonic qubits and
squeezed vacuum states. The proposal enables exploiting state-of-the-art
procedures for the non-deterministic generation of bosonic qubits combined with
the strengths of continuous-variable quantum computation, namely the
implementation of Clifford gates using easy-to-generate squeezed states.
Moreover, the architecture is based on two-dimensional integrated photonic
chips used to produce a qubit cluster state in one temporal and two spatial
dimensions. By reducing the experimental challenges as compared to existing
architectures and by enabling room-temperature quantum computation, our design
opens the door to scalable fabrication and operation, which may allow photonics
to leap-frog other platforms on the path to a quantum computer with millions of
qubits.Comment: 38 pages, many figures. Comments welcom
Decoy peptide targeted to Toll-IL-1R domain inhibits LPS and TLR4-active metabolite morphine-3 glucuronide sensitization of sensory neurons
Accumulating evidence indicates that Toll-like receptor (TLR) signaling adapter protein interactions with Toll/Interleukin-1 Receptor (TIR) domains present in sensory neurons may modulate neuropathic pain states. Following ligand interaction with TLRs, TIR serves to both initiate intracellular signaling and facilitate recruitment of signaling adapter proteins to the intracytoplasmic domain. Although TLR TIR is central to a number of TLR signaling cascades, its role in sensory neurons is poorly understood. In this study we investigated the degree to which TLR TIR decoy peptide modified to include a TAT sequence (Trans-Activator of Transcription gene in HIV; TAT-4BB) affected LPS-induced intracellular calcium flux and excitation in sensory neurons, and behavioral changes due to TLR4 active metabolite, morphine-3-glucuronide (M3G) exposure in vivo. TAT-4BB inhibited LPS-induced calcium changes in a majority of sensory neurons and decreased LPS-dependent neuronal excitability in small diameter neurons. Acute systemic administration of the TAT-4BB reversed M3G-induced tactile allodynia in a dose-dependent manner but did not affect motor activity, anxiety or responses to noxious thermal stimulus. These data suggest that targeting TLR TIR domains may provide novel pharmacological targets to reduce or reverse TLR4-dependent pain behavior in the rodent
Challenges to the recognition and assessment of Alzheimer's disease in American Indians of the southwestern United States
Little is known about Alzheimer’s disease (AD) and related neurodegenerative diseases in American Indian (AI) populations. To provide appropriate health care to elder AIs, whose population is expected to increase dramatically during the next 50 years, it is imperative to attain a better understanding of the interaction of culture and disease in this underserved population. Raising awareness in the AI population regarding the nature of dementia as it compares to normal aging and the development of culturally appropriate instruments to detect and stage AD are essential for future health care efforts. Barriers restricting clinical service to this population include historical factors relating to access to health care, cultural beliefs regarding aging, demographic diversity of the population, competing epidemiologic risk factors, and lack of proper assessment tools for clinicians