598 research outputs found
The positive response in grape secondary metabolites under controlled stresses: a review
Grapevine is cultivated worldwide with great economic importance. In recent years, our knowledge of the physiological and molecular basis of berry quality regulation has substantially increased. Abiotic and biotic stresses, such as deficit irrigation, low temperature, light/UV and microbes, to a certain extent, could improve grape berry quality by enhancing flavor metabolites, colorization or aroma compounds. This review summarizes recent data related to the stress of grape berry development, with special emphasis on secondary metabolism and its response to stresses. A full understanding of how grape berry metabolism responds to different stresses is important to improve the biochemical qualities of grapes and resultant products, such as wine in practice
Single-photon-triggered quantum chaos
We demonstrate how to manipulate quantum chaos with a single photon in a
hybrid quantum device combining cavity QED and optomechanics. Specifically, we
show that this system changes between integrable and chaotic relying on the
photon-state of the injected field. This onset of chaos originates from the
photon-dependent chaotic threshold of the qubit-field coupling induced by the
optomechanical interaction. By deriving the Loschmidt Echo we observe clear
differences in the sensitivity to perturbations in the regular versus chaotic
regimes. We also present classical analog of this chaotic behavior, and find
good correspondence between chaotic quantum dynamics and classical physics. Our
work opens up a new route to achieve quantum manipulations, which are crucial
elements in engineering new types of on-chip quantum devices and quantum
information science.Comment: 11 pages, 4 figure
Deep Learning the Effects of Photon Sensors on the Event Reconstruction Performance in an Antineutrino Detector
We provide a fast approach incorporating the usage of deep learning for
evaluating the effects of photon sensors in an antineutrino detector on the
event reconstruction performance therein. This work is an attempt to harness
the power of deep learning for detector designing and upgrade planning. Using
the Daya Bay detector as a benchmark case and the vertex reconstruction
performance as the objective for the deep neural network, we find that the
photomultiplier tubes (PMTs) have different relative importance to the vertex
reconstruction. More importantly, the vertex position resolutions for the Daya
Bay detector follow approximately a multi-exponential relationship with respect
to the number of PMTs and hence, the coverage. This could also assist in
deciding on the merits of installing additional PMTs for future detector plans.
The approach could easily be used with other objectives in place of vertex
reconstruction
Controlling atomic spin-mixing via multiphoton transitions in a cavity
We propose to control spin-mixing dynamics in a gas of spinor atoms, via the
combination of two off-resonant Raman transition pathways, enabled by a common
cavity mode and a bichromatic pump laser. The mixing rate, which is
proportional to the synthesized spin-exchange interaction strength, and the
effective atomic quadratic Zeeman shift (QZS), can both be tuned by changing
the pump laser parameters. Quench and driving dynamics of the atomic collective
spin are shown to be controllable on a faster time scale than in existing
experiments based on inherent spin-exchange collision interactions. The results
we present open a promising avenue for exploring spin-mixing physics of atomic
ensembles accessible in current experiments.Comment: 4.5pages with appendices, 3 figure
Genome-wide investigation and expression analyses of the pentatricopeptide repeat protein gene family in foxtail millet
Orthologous relationships of the PPR genes between foxtail millet and those of other grass species. (TIF 5719Â kb
Foxtail Millet NF-Y Families: Genome-Wide Survey and Evolution Analyses Identified Two Functional Genes Important in Abiotic Stresses
It was reported that Nuclear Factor Y (NF-Y) genes were involved in abiotic stress in plants. Foxtail millet (Setaria italica), an elite stress tolerant crop, provided an impetus for the investigation of the NF-Y families in abiotic responses. In the present study, a total of 39 NF-Y genes were identified in foxtail millet. Synteny analyses suggested that foxtail millet NF-Y genes had experienced rapid expansion and strong purifying selection during the process of plant evolution. De novo transcriptome assembly of foxtail millet revealed 11 drought up-regulated NF-Y genes. SiNF-YA1 and SiNF-YB8 were highly activated in leaves and/or roots by drought and salt stresses. Abscisic acid (ABA) and H2O2 played positive roles in the induction of SiNF-YA1 and SiNF-YB8 under stress treatments. Transient luciferase (LUC) expression assays revealed that SiNF-YA1 and SiNF-YB8 could activate the LUC gene driven by the tobacco (Nicotiana tobacam) NtERD10, NtLEA5, NtCAT, NtSOD or NtPOD promoter under normal or stress conditions. Overexpression of SiNF-YA1 enhanced drought and salt tolerance by activating stress-related genes NtERD10 and NtCAT1 and by maintaining relatively stable relative water content (RWC) and contents of chlorophyll, superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and malondialdehyde (MDA) in transgenic lines under stresses. SiNF-YB8 regulated expression of NtSOD, NtPOD, NtLEA5 and NtERD10 and conferred relatively high RWC and chlorophyll contents and low MDA content, resulting in drought and osmotic tolerance in transgenic lines under stresses. Therefore, SiNF-YA1 and SiNF-YB8 could activate stress-related genes and improve physiological traits, resulting in tolerance to abiotic stresses in plants. All these results will facilitate functional characterization of foxtail millet NF-Ys in future studies
- …