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In this article, an adaptive fixed-time cascaded distributed control is proposed for bipolar DC microgrid (MG) to achieve current sharing and voltage regulation at fixed time while eliminating the accuracy deviation effect of time delay. Compared with parallel distributed control based on double information exchange, the proposed cascade controller releases space through local voltage compensation, simplifies the controller structure, and saves computational resources. In order to enhance the time delay resilience and regulation sensitivity of the cascade control, an additional intermediate variable information exchange and proportional control are introduced. Based on this, the fixed-time algorithm is introduced into the cascade control to realize the objective fixed-time convergence and an adaptive rule based on local information is designed to select the control gain to enhance practicality. In addition, the stability of the system is ensured by rigorous small-signal and Lyapunov stability analyses, the effects of various parameters on the dynamic performance are investigated, while convergence time bounds and time delay margins are obtained. Finally, the experimental validation of the bipolar DC MG shows that the proposed strategy achieves control objectives with the advantages of fast convergence and resistance to time delay.

The double deprotonation of 2-aminomethyl pyridine by rare-earth metal triamido complexes was found to be an alternative strategy to anchor dianionic iminopyridine on rare-earth metal centers with the morpholinyl group previously. To verify the generality of the protocol with different appendant donor groups, reactions of [(Me3Si)2N]3RE(μ-Cl)Li(THF)3with ether/thiotether-substituted 2-aminomethyl pyridine 2-(CH3DCH2CH2NHCH2)-6-R-C5H3N (D = O, R = H (1), Ph (2); D = S, R = H (3)) were performed, leading to the formation of ether/thioether-functionalized dianionic α-iminopyridine rare-earth metal amido complexes {μ-η2:σ1:κ1:κ1-2-[CH3ECH2CH2NCH]-6-R-C5H3N}2RE2[N(SiMe3)2]2(D = O, R = H, RE = Dy (4a), Y (4b), Er (4c), Yb (4d), Lu (4e), R = Ph, RE = Dy (5a), Y (5b), Er (5c), Lu (5d); D = S, R = H, RE = Y (6a), Er (6b), Lu (6c)). These results supported the ability of oxygen or sulfur coordination in promoting the double deprotonation of 2-aminomethyl pyridine to construct new iminopyridine rare-earth metal complexes in the dianionic form. Further examination of these rare-earth metal amido complexes displayed good catalytic activity for hydrophosphination of alkenes, affording anti-Markovnikov addition products under solvent-free conditions.

Background: Phosphorus is a macronutrient necessary for plant growth and development and its availability and efficient use affect crop yields. Leaves are the largest tissue that uses phosphorus in plants, and membrane phospholipids are the main source of cellular phosphorus usage. Results: Here we identify a key process for plant cellular phosphorus recycling mediated by membrane phospholipid hydrolysis during leaf senescence. Our results indicate that over 90% of lipid phosphorus, accounting for more than one-third of total cellular phosphorus, is recycled from senescent leaves before falling off the plants. Nonspecific phospholipase C4(NPC4) and phospholipase Dζ2(PLDζ2) are highly induced during leaf senescence, and knockouts of PLDζ2and NPC4decrease the loss of membrane phospholipids and delay leaf senescence. Conversely, overexpression of PLDζ2and NPC4accelerates the loss of phospholipids and leaf senescence, promoting phosphorus remobilization from senescent leaves to young tissues and plant growth. We also show that this phosphorus recycling process in senescent leaves mediated by membrane phospholipid hydrolysis is conserved in plants. Conclusions: These results indicate that PLDζ2- and NPC4-mediated membrane phospholipid hydrolysis promotes phosphorus remobilization from senescent leaves to growing tissues and that the phospholipid hydrolysis-mediated phosphorus recycling improves phosphorus use efficiency in plants.

With global climate change, the agricultural light-temperature potential productivity in the agro-pastoral ecotone has increased. This offers a good opportunity to develop agriculture in the agro-pastoral ecotone. However, the agro-pastoral ecotone is also an ecologically fragile area in which land degradation challenges agricultural development. As population grows and the need for food increases, the land carrying capacity of the agro-pastoral ecotone becomes insufficient, and the human–land relationship is not harmonious. Such conditions have limited the agricultural and rural development in the ecotone. The paper demonstrates how land engineering may improve land quality and support agricultural development in the ecotone based on studies at a research station established in 2015 in Yulin, Shaanxi Province, China. The studies target three factors: soil improvement, crop selection, and field management. The results show that: (1) The highest yield of crops planted on improved land is close to or even higher than that achieved under previous crop growth conditions. For instance, the corn yields can exceed 25%. (2) The potatoes grown on the improved land yield the highest gross income, reaching 67,200 yuan/ha. By way of land engineering, input costs can be balanced in 3–5 years. (3) As a result of land engineering, some villages in Yulin City have realized sustainable agricultural and even rural development, and promotion of this model will support the sustainable development of agriculture in the agro-pastoral ecotone.

For state-of-charge (SOC) estimation with high precision, moving horizon estimation (MHE) has recently emerged as a competitive alternative to various Kalman filters or observers due to its significantly improved accuracy and robustness. However, MHE demands considerably higher computational complexity, preventing its deployment on a low-cost embedded microcontroller. To address this challenge, we propose a fast moving horizon SOC estimation algorithm to retain the benefits of MHE at a vastly reduced computational cost. In particular, we consider joint SOC and parameter estimation for an SOC-dependent equivalent circuit model subject to model mismatch. The proposed fast joint MHE (jMHE) algorithm performs a fixed number of Gauss–Newton (GN) iterations to approximate the fully converged solution. At each iteration, the GN Hessian matrix is factorized by exploiting its block tridiagonal structure to construct computationally efficient forward–backward recursions. To further speed up computations, another fast jMHE algorithm wtih an Event-Triggered Relinearization strategy (jMHE-ETR) is proposed to avoid refactorizing the GN Hessian matrix at each iteration. Using experimental datasets under different operating conditions, it is verified on both laptop and Raspberry Pi microcontroller that compared to the conventional optimal MHE solved with an off-the-shelf solver, the proposed fast jMHE and jMHE-ETR algorithms both have a slight loss of performance (still significantly better than extended Kalman filtering) while reducing its computational cost by an order of magnitude.

Fast and on-site detection is important for an effective antigene-doping strategy. However, the current gene doping (GD) evaluation methods require sophisticated instruments and laborious procedures, limiting their field applications. This study proposes a CRISPR/Cas12a-based detection platform (termed CasGDP) combining CRISPR/Cas12a and multiplexed Recombinase Polymerase Amplification (RPA) for rapid evaluation of GD. CasGDP showed high specificity for identifying the putative target genes such as EPO, IGF-1, and GH-1. By using fluorescence as the readout, the method achieved a limit-of-detection of 0.1 nM and 1 aM for unamplified and amplified target plasmids, respectively. Additionally, an in vitro GD cell model was successfully established with the human EPOgene (hEPO). The results indicated that the hEPOgene transfection promoted the hEPOprotein expression. Furthermore, trace amounts of EPOtransgene spiked in human serum were efficiently measured by CasGDP with fluorescence- and lateral flow device (LFD)-based readouts in 40 min. Finally, we designed a multiplexed microfluidic device and realized simultaneous detection of the three transgenes via LFD embedded in the device. To our knowledge, this is the first work that combines the CRISPR-based system and multiplexed RPA for GD detection. We anticipate CasGDP to be widely used as a rapid, sensitive, and robust tool for GD evaluation.

Background: Skeletal muscle tissue engineering (SMTE) is of great significance in the study of skeletal muscle physiology and pathology, which could be used in skeletal muscle graft. The scientometric analysis of SMTE can help researchers to quickly understand the evolutive history, status, novelties, and trend of this field. Experiment: In this study, we performed a scientometric study that can be used to construct and visualize networks of SMTE by using VOSviewer. A total of 1384 documents published between 1994 and 2020were retrieved and analyzed. Results: Our results showed that number of publications in SMTE has increased slowly from 1994 to 2014 and has increased rapidly from 2015 to 2020. The geographical distribution of publications in term of total publications about SMTE is concentrated in Europe and the United States. The most productive institution was University of Michigan, while Harvard University and the University of Pittsburgh was ranked the second and third places. SMTE influenced a wide spectrum of disciplines including Biology and Medicine, and Physical Sciences. In addition, the research hotspot of SMTE were expanding from seed cells to the combination with advanced strategies (electrostatic spinning, bioprinting, and materials) for emulating the highly bionic engineered skeletal muscle tissues. Conclusions: This study provided a unique perspective for understand the history and trends of SMTE, which could help to promote the rapid development of the field.