TFL1-, AP1- and LFY-like genes are known to be key regulators of inflorescence development. However, it remains to be tested whether the evolutionary modifications of inflorescence morphology result ...from shifts in their expression patterns.
We compared the spatiotemporal expression patterns of CorTFL1, CorAP1 and CorLFY in six closely related Cornus species that display four types of closed inflorescence morphology using quantitative real-time polymerase chain reaction (qRT-PCR) and RNA in situ hybridization. Character mapping on the phylogeny was conducted to identify evolutionary changes and to assess the correlation between changes in gene expression and inflorescence morphology.
Results demonstrated variation of gene expression patterns among species and a strong correlation between CorTFL1 expression and the branch index of the inflorescence type. Evolutionary changes in CorTFL1 and CorAP1 expression co-occurred on the phylogeny with the morphological changes underpinning inflorescence divergence.
The study found a clear correlation between the expression patterns of CorTFL1 and CorAP1 and the inflorescence architecture in a natural system displaying closed inflorescences. The results suggest a role for the alteration in CorTFL1 and CorAP1 expression during the evolutionary modification of inflorescences in Cornus. We propose that a TFL1-like and AP1-like gene-based model may explain variation of closed inflorescences in Cornus and other lineages.
Low-temperature severely affects the growth and development of chrysanthemum which is one kind of ornamental plant well-known and widely used in the world. Lysine crotonylation is a recently ...identified post-translational modification (PTM) with multiple cellular functions. However, lysine crotonylation under low-temperature stress has not been studied.
Proteome-wide and lysine crotonylation of chrysanthemum at low-temperature was analyzed using TMT (Tandem Mass Tag) labeling, sensitive immuno-precipitation, and high-resolution LC-MS/MS. The results showed that 2017 crotonylation sites were identified in 1199 proteins. Treatment at 4 °C for 24 h and - 4 °C for 4 h resulted in 393 upregulated proteins and 500 downregulated proteins (1.2-fold threshold and P < 0.05). Analysis of biological information showed that lysine crotonylation was involved in photosynthesis, ribosomes, and antioxidant systems. The crotonylated proteins and motifs in chrysanthemum were compared with other plants to obtain orthologous proteins and conserved motifs. To further understand how lysine crotonylation at K136 affected APX (ascorbate peroxidase), we performed a site-directed mutation at K136 in APX. Site-directed crotonylation showed that lysine decrotonylation at K136 reduced APX activity, and lysine complete crotonylation at K136 increased APX activity.
In summary, our study comparatively analyzed proteome-wide and crotonylation in chrysanthemum under low-temperature stress and provided insights into the mechanisms of crotonylation in positively regulated APX activity to reduce the oxidative damage caused by low-temperature stress. These data provided an important basis for studying crotonylation to regulate antioxidant enzyme activity in response to low-temperature stress and a new research ideas for chilling-tolerance and freezing-tolerance chrysanthemum molecular breeding.
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•Photoelectric co-excited ferroelectric artificial synapse is reported.•Bi2FeMnO6 of R3c phase is reported for the first time with ferroelectricity.•The neural network based on ...Bi2FeMnO6 synapse achieves 98.80% handwritten digit recognition accuracy.
Photoelectric synapse is a new type of artificial synapse that combines light pulse excitation and electrical pulse excitation, and is an important component for the development of neuromorphic hardware. In this work, the Bi2FeMnO6 ferroelectric artificial synapse with optoelectronic response is reported. It can generate an excitatory post-synaptic current through ultraviolet light irradiation and then modulate the excitatory post-synaptic current through ferroelectric polarization, thereby realizing a photo-ferroelectric dual-control synapse. A training method based on ultraviolet excitation and ferroelectric enhancement is proposed, which greatly reduced the number of training pulses and increased the plasticity of the synapse. The optimized spike scheme based on ferroelectricity is proposed, which made the synapse have very linear weight adjustment function. This synapse is used to build a convolutional neural network, which can achieve 98.80% recognition accuracy on the MNIST dataset. In addition, the ferroelectricity and multi-level resistive switching effect of synapse have also been reported.
Barium titanate (BaTiO3) and Bismuth ferrite (BiFeO3) have been investigated for many years. Both of them have good electrical properties in the application of industries such as flexible displays, ...actuators, transducers, flexible memory, multilayer ceramic capacitors, etc. Moreover, BiFeO3 is a room temperature multiferroic material that adds a halo to it. Although there are some shortcomings compared with some properties of lead-based ceramics, environmental friendly materials will be the future trend. The solid solution of BaTiO3 and BiFeO3 exactly meets this requirement. There are many reports related to it, but there are few systemic articles focused on it. So, this review recalls the progress of binary ferroelectric material: BaTiO3–BiFeO3 ceramic, especially in the field of ferroelectric, piezoelectric, energy-storage properties. Furthermore, the preparation approaches to functional ceramics are also illustrated here. Finally, we deliver a summary of this material.
In the case of dielectric energy storage devices, excessive pursuit of giant electric fields means greater exposure to high temperatures and insulation damage risk. Ferroelectric thin film devices ...offer opportunities for energy storage needs under finite electric fields due to their intrinsically large polarization and the advantage of small size. Herein, we designed the capacitor's dielectric layer by doping barium titanate Ba (1-x) Ce x TiO 3 (BCTO). The addition of highly charged ions Ce 3+ induce cell shrinkage thus further optimizing the ferroelectric polarization. Accordingly, the capacitor with Au/BCTO/Au structure integrated directly on silicon substrate showed excellent energy storage performance ( W rec ≈ 92.6 J/cm 3 and η ≈ 86.5%) under only 1961 kV/cm. In addition, we significantly increased the electrical breakdown strength from 1726 kV/cm to 3426 kV/cm by adjusting the Ba 0.95 Ce 0.05 TiO 3 film thickness, thus achieving ultra-high energy storage density (107.9 J/cm 3 ). The results expand the application prospects of silicon-based ferroelectric capacitors for energy storage at low electric field strength.
HfO2 thin film is deposited on p-Si substrates by RF magnetron sputtering apparatus and annealed at 750 °C for 10 min with O2 atmosphere. Spectral analysis shows that HfO2 thin films have good ...transmittance to light, especially ultraviolet band. The HfO2 layers belong monoclinic phase and its thickness is about 50 nm. In the Au/HfO2/p-Si structure, photodiode characteristics were studied at room temperature and compared with the light current generated under white light, the response current generated under ultraviolet light is more prominent. The photocurrent reaches 80 μA and the repeatable response of device under 23.5 mW/cm2 ultraviolet illuminating is stable. It's found that the working mechanism of this photodiode could have three different states: the majority carrier stacking state of reverse bias, the majority carrier depletion state of forward bias with dark condition and the minority carrier inversion state of forward bias with ultraviolet illumination. The device also has a high damage threshold and its photocurrent is still not saturated at bias 8 V, indicating that it can be applied as a new type of UV detector.
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•A photodiode with an Au/HfO2/p-Si structure is fabricated.•The photocurrent increases with the intensity of ultraviolet light, with a maximum of 80 μA.•This photodiode also has a high damage threshold and its photocurrent is still unsaturated at an 8 V bias.
Coronavirus disease 2019 (COVID-19) is a novel and lethal infectious disease, posing a threat to global health security. The number of cases has increased rapidly, but no data concerning kidney ...transplant (KTx) recipients infected with COVID-19 are available. To present the epidemiological, clinical, and therapeutic characteristics of KTx recipients infected with COVID-19, we report on a case series of five patients who were confirmed as having COVID-19 through nucleic acid testing (NAT) from January 1, 2020 to February 28, 2020. The most common symptoms on admission to hospital were fever (five patients, 100%), cough (five patients, 100%), myalgia or fatigue (three patients, 60%), and sputum production (three patients, 60%); serum creatinine or urea nitrogen levels were slightly higher than those before symptom onset. Four patients received a reduced dose of maintenance immunosuppressive therapy during hospitalization. As of March 4, 2020 NAT was negative for COVID-19 in three patients twice in succession, and their computed tomography scans showed improved images. Although greater patient numbers and long-term follow-up data are needed, our series demonstrates that mild COVID-19 infection in KTx recipients can be managed using symptomatic support therapy combined with adjusted maintenance immunosuppressive therapy.
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