Salt stress can significantly affect plant growth and agricultural productivity. Receptor-like kinases (RLKs) are believed to play essential roles in plant growth, development, and responses to ...abiotic stresses. Here, we identify a receptor-like cytoplasmic kinase, salt tolerance receptor-like cytoplasmic kinase 1 (STRK1), from rice (Oryza sativa) that positively regulates salt and oxidative stress tolerance. Our results show that STRK1 anchors and interacts with CatC at the plasma membrane via palmitoylation. CatC is phosphorylated mainly at Tyr-210 and is activated by STRK1. The phosphorylation mimic form CatCY210D exhibits higher catalase activity both in vitro and in planta, and salt stress enhances STRK1-mediated tyrosine phosphorylation on CatC. Compared with wild-type plants, STRK1-overexpressing plants exhibited higher catalase activity and lower accumulation of H2O2 as well as higher tolerance to salt and oxidative stress. Our findings demonstrate that STRK1 improves salt and oxidative tolerance by phosphorylating and activating CatC and thereby regulating H2O2 homeostasis. Moreover, overexpression of STRK1 in rice not only improved growth at the seedling stage but also markedly limited the grain yield loss under salt stress conditions. Together, these results offer an opportunity to improve rice grain yield under salt stress.
In recent years, α‐imino rhodium carbene complexes derived by ring‐opening of N‐sulfonyl‐1,2,3‐triazoles have attracted much attention from organic chemists. Many transformations of these species ...have been reported that involve, in most cases, nucleophilic attack at the carbene center of the α‐imino rhodium carbene, facilitating the synthesis of a wide range of novel and useful compounds, particularly heterocycles. This Minireview mainly focuses on advances in the transformation of N‐sulfonyl‐1,2,3‐triazoles during the past two years.
In recent years, α‐imino rhodium carbene complexes derived from N‐sulfonyl‐1,2,3‐triazoles have attracted much attention for their application in the synthesis of heterocycles and related species. In most cases, ring‐opening of the triazole to afford the α‐imino rhodium carbene is followed by nucleophilic attack at the carbene center to afford a wide range of useful compounds.
Perovskite Light‐emitting diodes (PeLEDs) have emerged as a promising technique for future high‐definition displays due to their outstanding electroluminescent characters. However, the development of ...blue PeLEDs toward practical applications is seriously hindered by their inferior performance, which mainly arises from the detrimental halide ionic behavior and thus severe nonradiative recombination in mixed‐halide blue perovskite materials. Herein, efficient sky‐blue PeLEDs featuring spectrally stable emission at 483 nm are realized by employing bifunctional passivators of Lewis‐base benzoic acid anions and alkali metal cations to simultaneously passivate the under‐coordinated lead atoms and suppress halide ion migration. A decent external quantum efficiency (EQE) of 16.58% and a maximum EQE of 18.65% are achieved, which is further boosted to 28.82% through the optical outcoupling enhancement. This work demonstrates unique insight into the generality and individuality of this category of benzoates and puts forward a feasible guidance in choosing appropriate additives for efficient perovskite materials.
Defect passivation and the suppression of halide ion migration are simultaneously achieved in mixed‐halide perovskite materials via the incorporation of bifunctional additives containing Lewis‐base group and alkali metal ions. Efficient sky‐blue perovskite light‐emitting diodes achieve an external quantum efficiency of 16.58%, which is further boosted to 28.82% by the optical outcoupling enhancement.
Twitter, a popular microblogging social networking site, allows individuals to communicate by sending short messages of up to 140 characters. Although it enables people to be in constant contact, its ...value in educational context is less clear. This paper is the first to examine empirical studies of using Twitter in teaching and learning over 10 years from 2006 to 2015, with the aim of understanding whether its implementation would benefit students or not. We identified a total of 51 eligible publications, and reported the analysis in four major categories: (a) the profile of studies, (b) the specific ways in which Twitter was employed in education, (c) the impacts on interactions, and (d) the impacts on students' learning outcomes. The findings reveal that Twitter was most commonly used for communication and assessment purposes. Although Twitter shows promise in improving interactions among learners and teachers, causality between Twitter use and learning performance remains to be conclusively established. Currently, the most beneficial use of Twitter is probably that of a “push” technology – such as the instructor sending important course information, homework assignments and test deadlines to students, as well as that of a platform for peer interaction. Many challenges still exist in using Twitter for teaching and learning. Based on our review of the literature, we proposed five guidelines that could help promote the educational value of Twitter use. We also identified several limitations of previous studies, and offered suggestions for future work.
•This review is the first to examine empirical studies of using Twitter in teaching and learning over 10 years.•Using Twitter could possibly improve learning outcomes, especially as a “push” technology and a peer interaction platform.•Using Twitter could facilitate content communication and peer interaction.•Challenges exist, such as students' unfamiliarity, distraction, and privacy.
The increased global demand for plastic materials has led to severe plastic waste pollution, particularly to the marine environment. This critical issue affects both sea life and human beings since ...microplastics can enter the food chain and cause several health impacts. Plastic recycling, chemical treatments, incineration and landfill are apparently not the optimum solutions for reducing plastic pollution. Hence, this review presents two newly identified environmentally friendly approaches, plastic biodegradation and bioplastic production using algae, to solve the increased global plastic waste. Algae, particularly microalgae, can degrade the plastic materials through the toxins systems or enzymes synthesized by microalgae itself while using the plastic polymers as carbon sources. Utilizing algae for plastic biodegradation has been critically reviewed in this paper to demonstrate the mechanism and how microplastics affect the algae. On the other hand, algae-derived bioplastics have identical properties and characteristics as petroleum-based plastics, while remarkably being biodegradable in nature. This review provides new insights into different methods of producing algae-based bioplastics (e.g., blending with other materials and genetic engineering), followed by the discussion on the challenges and further research direction to increase their commercial feasibility.
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•Marine plastic pollution endangers and affects aquatic wildlife and their habitat.•Interaction between algal enzymes and plastic polymers triggers biodegradation.•Bioplastics can be made using protein- and carbohydrate-based polymers from algae.•Production of polymers from algae can be enhanced through genetic engineering.•Conventional plastics could be fully replaced by algal bioplastics in the future.
A giant electrocaloric effect (ECE) near room temperature is reported in a lead‐free bulk inorganic material. By tuning Ba(ZrxTi1–x)O3 compositions which also exhibit relaxor ferroelectric response ...to near the invariant critical point, the Ba(ZrxTi1–x)O3 bulk ceramics at x ∼ 0.2 exhibit a large adiabatic temperature drop of 4.5 K, a large isothermal entropy change of 8 J kg−1 K−1, and a large EC coefficient (|ΔTc/ΔE| = 0.52 × 10−6 KmV−1 and ΔS/ΔE = 0.93 × 10−6 J m kg−1 K−1 V−1) over a 30 K temperature range. These properties added together indicate a general solution of the electrocaloric materials with high performance for practical cooling applications.
A giant electrocaloric effect (ECE), i.e., a large adiabatic temperature drop (ΔTc) with a high electrocaloric coefficient (ΔTc/ΔE), is demonstrated in a modified lead‐free ferroelectric ceramic, BaTiO3, over a broad temperature range near the invariant critical point (ICP). Multiphase coexistence near ICP provides a larger entropy change compared with that of a pure ferroelectric–paraelectric transition. When coupled with the relaxor behavior, this leads to the observed giant ECE in BZT (x = 0.2) over a broad temperature range
The inflammation is the protective response of the body against various harmful stimuli; however, the aberrant and inappropriate activation tends to become harmful. The acute inflammatory response ...tends to resolved once the offending agent is subside but this acute response becomes chronic in nature when the body is unable to successfully neutralized the noxious stimuli. This chronic inflammatory microenvironment is associated with the release of various pro-inflammatory and oncogenic mediators such as nitric oxide (NO), cytokines IL-1β, IL-2, interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α), growth factor, and chemokines. These mediators make the inflammatory microenvironment more vulnerable toward tumorigenesis. The pro-inflammatory mediators released during the chronic inflammation tends to induce several molecular signaling cascades such as nuclear factor kappa B, MAPKinase, nuclear factor erythroid 2-related factor 2, phosphoinositide-3-kinase, Janus kinases/STAT, Wnt/B-catenin, and cyclic AMP response element binding protein. The immune system and its components have a pleiotropic effect on inflammation and cancer progression. Immune components such as T cells, natural killer cells, macrophages, and neutrophils either inhibit or enhance tumor initiation depending on the type of tumor and immune cells involved. Tumor-associated macrophages and tumor-associated neutrophils are pro-tumorigenic cells highly prevalent in inflammation-mediated tumors. Similarly, presence of T regulatory (Treg) cells in an inflammatory and tumor setting suppresses the immune system, thus paving the way for oncogenesis. However, Treg cells also inhibit autoimmune inflammation. By contrast, cytotoxic T cells and T helper cells confer antitumor immunity and are associated with better prognosis in patients with cancer. Cytotoxic T cells inflict a direct cytotoxic effect on cells expressing oncogenic markers. Currently, several anti-inflammatory and antitumor therapies are under trials in which these immune cells are exploited. Adoptive cell transfer composed of tumor-infiltrating lymphocytes has been tried for the treatment of tumors after their
expansion. Mediators released by cells in a tumorigenic and inflammatory microenvironment cross talk with nearby cells, either promoting or inhibiting inflammation and cancer. Recently, several cytokine-based therapies are either being developed or are under trial to treat such types of manifestations. Monoclonal antibodies directed against TNF-α, VEGF, and IL-6 has shown promising results to ameliorate inflammation and cancer, while direct administration of IL-2 has been shown to cause tumor regression.
Circular RNAs, a novel class of endogenous noncoding RNAs, are characterized by their covalently closed loop structures without a 5' cap or a 3' Poly A tail. Although the mechanisms of circular RNAs' ...generation and function are not fully clear, recent research has shown that circular RNAs may function as potential molecular markers for disease diagnosis and treatment and play an important role in the initiation and progression of human diseases, especially in tumours. This review summarizes some information about categories, biogenesis, functions at the molecular level, properties of circular RNAs and the possibility of circular RNAs as biomarkers in cancers.
Gold catalysis is often the key step in the synthesis of natural products, and is a powerful tool for tandem or domino reaction processes. Both gold salts and complexes are among the most powerful ...soft Lewis acids for electrophilic activation of carbon–carbon multiple bonds toward a variety of nucleophiles. The core of these reactions relies on the interaction between gold catalysts and π-bonds of alkenes, alkynes, and allenes. Activation of functional groups by gold complexes provides a useful and important method for facilitating many different organic transformations with high atom efficiency. Although they are highly strained, methylenecyclopropanes (MCPs) and vinylidenecyclopropanes (VDCPs) are readily accessible molecules that have served as useful building blocks in organic synthesis. Because of their unique structural and electronic properties, significant developments have been made in the presence of transition metal catalysts such as nickel, rhodium, palladium, and ruthenium during the past decades. However, less attention has been paid to the gold-catalyzed chemistry of MCPs and VDCPs. In this Account, we describe gold-catalyzed chemical transformations of MCPs and VDCPs developed both in our laboratory and by other researchers. Chemists have demonstrated that MCPs and VDCPs have amphiphilic properties. When MCPs or VDCPs are activated by a gold catalyst, subsequent nucleophilic attack by other reagents or ring-opening (ring-expansion) of the cyclopropane moiety will occur. However, the C–C double bonds of MCPs and VDCPs can also serve as nucleophilic reagents while more electrophilic reagents are present and activated by gold catalyst, and then further cascade reactions take place as triggered by the release of ring strain of cyclopropane. Based on this strategy, both our group and others have found some interesting gold-catalyzed transformations in recent years. These transformations of MCPs and VDCPs can produce a variety of polycyclic and heterocyclic structures, containing different sized skeletons. Moreover, we have carried out some isotopic labeling experiments and computational studies for mechanistic investigation. These reactions always give the desired products with high level control of chemo-, regio-, and diastereoselectivities, making them highly valuable for the synthesis of natural products and to the pharmaceutical industry and medicine in general.
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