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An EMS (ethy methanesulfonate)-induced lethal etiolated (le) mutant obtained from the rice variety Zhongjian 100 was characterized by lethal etiolated phenotypes, with significantly reduced levels of chlorophyll a, chlorophyll b, total chlorophyll, and carotenoids. Additionally, the mutant displayed a significantly decreased number of chloroplast grana, along with irregular and less-stacked grana lamellae. The le mutant showed markedly diminished root length, root surface area, and root volume compared with the wild type. It also exhibited significantly lower catalase activity and total protein content, while peroxidase activity was significantly higher. Using the map-based cloning method, we successfully mapped the LE gene to a 48-kb interval between markers RM16107 and RM16110 on rice chromosome 3. A mutation (from T to C) was identified at nucleotide position 692 bp of LOC_Os03g59640 (ChlD), resulting in a change from leucine to proline. By crossing HM133 (a pale green mutant with a single-base substitution of A for G in exon 10 of ChlD subunit) with a heterozygous line of le (LEle), we obtained two plant lines heterozygous at both the LE and HM133 loci. Among 15 transgenic plants, 3 complementation lines displayed normal leaf color with significantly higher total chlorophyll, chlorophyll a, and chlorophyll b contents. The mutation in le led to a lethal etiolated phenotype, which has not been observed in other ChlD mutants. The mutation in the AAA+ domain of ChlD disrupted the interaction of ChlDle with ChlI as demonstrated by a yeast two-hybrid assay, leading to the loss of ChlD function and hindering chlorophyll synthesis and chloroplast development. Consequently, this disruption is responsible for the lethal etiolated phenotype in the mutant.

Alzheimer’s disease is known as one of the “top ten killers in the world”. Due to lack of effective therapy at present， early pathological changes have captivated widespread attention. Axonal transport dysfunction has been reported as an early pathological feature of many neurodegenerative diseases. However， multiple factors can cause axonal transport dysfunction. In this article， the relationship between axonal transport dysfunction caused by kinesins， microtubules and mitochondria and Alzheimer’s disease was discussed， aiming to provide new ideas for the prevention and treatment of Alzheimer’s disease by in-depth study on axonal transport mechanism of neure.

Internal calibration measures the changes in amplitude and phase of a system during imaging via the calibration loop built in Synthetic Aperture Radar (SAR). Internal calibration is also an important factor to improve the radiation accuracy of the radar. In this study, a novel wireless internal calibration method with auxiliary antenna is presented, considering that the traditional scheme is inefficient, as the calibration loop cannot cover the path from the TR (Transmitter-Receiver) output to the antenna radiator. The calibration loop also results in a complicated and heavy network. The principle and model of the new method is given, and the TR performance and system transfer function calibration approach are deduced. In addition, error analysis is conducted. The simulation results show that TR amplitude calibration errors caused by the rod of auxiliary antenna are at a 10–3 dB level, and phase calibration errors are obtained from the simulation curve in the paper; transfer function amplitude calibration errors are less than 0.1 dB, and phase calibration errors are not sensitive to the bias of the rod. Finally, the simulation results based on typical parameters of spaceborne SAR and the individual TR calibration experiments confirm the availability and feasibility of this novel method.

Alzheimer's disease (AD) is the most common form of dementia and a significant social and economic burden. Estrogens can exert neuroprotective effects and may contribute to the prevention, attenuation, or even delay in the onset of AD; however, long-term estrogen therapy is associated with harmful side effects. Thus, estrogen alternatives are of interest for countering AD. Naringin, a phytoestrogen, is a key active ingredient in the traditional Chinese medicine Drynaria. Naringin is known to protect against nerve injury induced by amyloid beta-protein (Aβ) 25–35, but the underlying mechanisms of this protection are unclear. To investigate the mechanisms of naringin neuroprotection, we observed the protective effect on Aβ25–35-injured C57BL/6J mice's learning and memory ability and hippocampal neurons. Then, an Aβ25–35 injury model was established with adrenal phaeochromocytoma (PC12) cells. We examined the effect of naringin treatment on Aβ25–35-injured PC12 cells and its relationship with estrogen receptor (ER), phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT), and glycogen synthase kinase (GSK)-3β signaling pathways. Estradiol (E2) was used as a positive control for neuroprotection. Naringin treatment resulted in improved learning and memory ability, the morphology of hippocampal neurons, increased cell viability, and reduced apoptosis. We next examined the expression of ERβ, p-AKT (Ser473, Thr308), AKT, p-GSK-3β (Ser9), GSK-3β, p-Tau (Thr231, Ser396), and Tau in PC12 cells treated with Aβ25–35 and either naringin or E2, with and without inhibitors of the ER, PI3K/AKT, and GSK-3β pathways. Our results demonstrated that naringin inhibits Aβ25–35-induced Tau hyperphosphorylation by modulating the ER, PI3K/AKT, and GSK-3β signaling pathways. Furthermore, the neuroprotective effects of naringin were comparable to those of E2 in all treatment groups. Thus, our results have furthered our understanding of naringin's neuroprotective mechanisms and indicate that naringin may comprise a viable alternative to estrogen therapy. [ABSTRACT FROM AUTHOR]

The reaction and separation sections are the keys to the methanol-to-olefins (MTO) chemical processes, and they should be optimized to reduce the cost of production. This work develops a framework for the simultaneous design and optimization of the reaction and distillation sections. An optimization model with shortcut and rigorous methods combined is established for distillation columns to improve accuracy and efficiency. With the auxiliary devices and the selection of utilities considered, the reaction and distillation sections are integrated to maximize profits. The genetic algorithm targets the optimal parameters, including the catalyst's coke content and reaction temperature, each column's operating pressure, and the allocation of utilities and auxiliary devices. For the studied MTO process, the optimal reaction temperature and catalyst's coke content were identified to be 496 °C and 7.8%, respectively. The maximum profit is 15.3% greater than that identified with only the separation section optimized, and the minimum total annual cost (TAC) of the separation section is 3.73% less. [ABSTRACT FROM AUTHOR]