Plant metabolites vary at different stages of their life cycle. Although it is well documented that environmental factors stimulate biosynthesis of secondary metabolites, the regulation by endogenous ...developmental cues remains poorly understood. The microRNA156 (miR156)-targeted SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) factors function as a major age cue in regulating developmental phase transition and flowering. We show here that the miR156-targeted SPL transcription factor plays an important role in the spatiotemporal regulation of sesquiterpene biosynthesis. In Arabidopsis thaliana, the miR156-SPL module regulates the formation of (E)-β-caryophyllene in the flowering stage through modulating expression of the sesquiterpene synthase gene TPS21. We demonstrated that SPL9 directly binds to TPS21 promoter and activates its expression. In the perennial fragrant herb Pogostemon cablin, the accumulation of patchouli oil, largely composed of sesquiterpenes dominated by (−)-patchoulol, is also age-regulated, and the SPL promotes biosynthesis of sesquiterpenes in elder plants by upregulating patchoulol synthase (PatPTS) gene expression. As miR156-SPLs are highly conserved in plants, our finding not only uncovers a molecular link between developmental timing and sesquiterpene production but also suggests a new strategy to engineer plants for accelerated growth with enhanced production of terpenoids.
The miR156-SPL module directly regulates expression of sesquiterpene synthase genes. This uncovers a molecular link between developmental timing and sesquiterpene production and suggests a new strategy to boost essential oil production in a shortened period of plant growth.
We show that a high key rate of Measurement-Device-Independent Quantum Key Distribution (MDIQKD) over asymmetric and unstable quantum channel can be obtained by full optimization and compensation. ...Employing a gradient optimization method, we make the full optimization taking both the global optimization for the 12 independent parameters and the joint constraints for statistical fluctuations. We present a loss-compensation method by monitoring the channel loss for an unstable channel. The numerical simulation shows that the method can produce high key rate for both the asymmetric channel and the unstable channel. Compared with the existing results of independent constraints, our result here improves the key rate by 1 to tens of times in typical experimental conditions.
•Olfactory defects in preclinical Alzheimer's disease (AD) can be targeted for effective therapies•Reduced presynaptic inhibitory transmissions in the olfactory bulb (OB) cause olfactory ...deficits•Increase in GABAA receptor activity rescues inhibitory transmission•Local GABAergic microcircuits in the OB are potential therapeutic targets for AD
Olfactory damage develops at the early stages of Alzheimer's disease (AD). While amyloid-β (Aβ) oligomers are shown to impair inhibitory circuits in the olfactory bulb (OB), its underlying mechanisms remain unclear. Here, we investigated the olfactory dysfunction due to impaired inhibitory transmission to mitral cells (MCs) of the OB in APP/PS1 mice. Using electrophysiological studies, we found that MCs exhibited increased spontaneous firing rates as early as 3 months, much before development of Aβ deposits in the brain. Furthermore, the frequencies but not amplitudes of MC inhibitory postsynaptic currents decreased markedly, suggesting that presynaptic GABA release is impaired while postsynaptic GABAA receptor responses remain intact. Notably, muscimol, a GABAA receptor agonist, improved odor identification and discrimination behaviors in APP/PS1 mice, reduced MC basal firing activity, and rescued inhibitory circuits along with reducing the Aβ burden in the OB. Our study links the presynaptic deficits of GABAergic transmission to olfactory dysfunction and subsequent AD development and implicates the therapeutic potential of maintaining local inhibitory microcircuits against early AD progression.
Gravity exploration is one of the most commonly used geophysical exploration methods, and it is widely used in the field of mineral resources' exploration and engineering survey benefited from its ...advantages of large exploration depth, economy, and high efficiency. Gravity and its gradient data reflect the different distribution characteristics of subsurface anomalous objects, and therefore, the single data inversion cannot achieve an accurate identification for the underground objects and suffer from stronger nonuniqueness problems. To accurately identify the location and distribution characteristics of subsurface objects, we first construct models to perform separate inversions of gravity and gravity gradient data, analyze the identification ability of different anomaly components, and then innovatively introduce a cross-gradient function for the joint inversion of two gravity tensor data, <inline-formula> <tex-math notation="LaTeX">{V}_{ {xx}} </tex-math></inline-formula> and <inline-formula> <tex-math notation="LaTeX">{V}_{ {yy}} </tex-math></inline-formula>. The results show that the method combines the advantages of these two components and reflects the horizontal position of the targeted bodies more accurately; meanwhile, the portrayal of the boundary is also closer to the real model. Finally, we apply the above method to the Vinton Dome, and the inversion results recover the accurate spatial location of the Vinton Dome. The practical application results show that the joint cross-gradient inversion of gravity and gravity gradient data is more efficient for spatial location trapping and boundary inscription of subsurface targeted bodies compared with the inversion of individual component.
Abstract
The sending-or-not-sending (SNS) protocol of the twin-field (TF) quantum key distribution (QKD) can tolerant large misalignment error and its key rate can exceed the linear bound of ...repeaterless QKD. The original SNS protocol and all variants of TF-QKD require perfect vacuum sources, but in the real world experiments there is no practical perfect vacuum source. Instead, experimenters use extremely weak sources to substitute vacuum sources, which may break the security of the protocol. Here we propose an SNS protocol with imperfect vacuum sources and give the non-asymptotic decoy-state analysis of this protocol. Our numerical simulation shows that when the imperfect vacuum sources are close to perfect vacuum sources, our protocol can obtain similar key rate as that with perfect vacuum sources. This is the first result that closes the potential security loophole due to imperfect vacuum of TF-QKD.
Quantum key distribution can provide unconditionally secure key exchange for remote users in theory. In practice, however, in most quantum key distribution systems, quantum hackers might steal the ...secure keys by observing the side channels in the emitted photons, such as the photon frequency spectrum, emission time, propagation direction, spatial angular momentum, and so on. It is hard to prevent such kinds of attacks because side channels may exist in many dimensions of the emitted photons. Here we report an experimental realization of a side-channel-secure quantum key distribution protocol which is not only measurement-device independent, but also immune to all side-channel attacks to the photons emitted from Alice's and Bob's labs. We achieve a secure key rate of 1.73×10^{-6} per pulse through 50 km fiber spools.
A novel and facile visible-light-mediated alkylation of indoles and nitroalkenes has been developed. In this protocol, rose bengal acts as a photosensitizer, and environmentally benign water was used ...as the green and efficient reaction medium. Indoles reacted smoothly with nitroalkenes under the irradiation of visible-light and generated corresponding 3-(2-nitroalkyl)indoles in moderate to good yields (up to 87%).
Abstract
The sending-or-not-sending (SNS) protocol is one of the most major variants of the twin-field (TF) quantum key distribution (QKD) protocol and has been realized in a 511-km field fiber, the ...farthest field experiment to date. In practice, however, all decoy-state methods have unavoidable source errors, and the source errors may be non-random, which compromises the security condition of the existing TF-QKD protocols. In this study, we present a general approach for efficiently calculating the SNS protocol’s secure key rate with source errors, by establishing the equivalent protocols through virtual attenuation and the tagged model. This makes the first result for TF QKD in practice where source intensity cannot be controlled exactly. Our method can be combined with the two-way classical communication method such as active odd-parity pairing to further improve the key rate. The numerical results show that if the intensity error is within a few percent, the key rate and secure distance only decrease marginally. The key rate of the recent SNS experiment in the 511-km field fiber is still positive using our method presented here, even if there is a $\pm 9.5\%$ intensity fluctuation. This shows that the SNS protocol is robust against source errors.
Robust twin-field QKD protocol through sending-or-not-sending is proposed, producing secure bits efficiently with intensity errors of source pulses.
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