Investigation of TDNA plugin events throughout transgenic grain

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Herein, we disclose an NHC-catalyzed aerobic oxidation of unactivated aldimines for the synthesis of amides via umpolung of imines proceeding through an aza-Breslow intermediate. We have developed an eco-friendly method for the conversion of imines to amides by using molecular oxygen in air as the sole oxidant and dimethyl carbonate (DMC) as a green solvent under mild reaction conditions. Broad substrate scope, high yields and gram scale syntheses expand the practicality of the developed method.As one of the most common marine sponges in tropical and subtropical oceans, the sponges of the genus Agelas, have emerged as unique and yet under-investigated pools for discovery of natural products with fabulous molecular diversity and myriad interesting biological activities. The present review highlights the chemical structure and biological activity of 355 compounds that have been isolated and characterized from the members of Agelas sponges, over the period of about five decades (from 1971 to November 2021). For a better understanding, these numerous compounds are firstly classified and presented according to their carbon skeleton as well as their biosynthetic origins. Relevant summaries focusing on the source organism and the associated bioactivity of these compounds belonging to different chemical classes are also provided. This review highlights sponges of the genus Agelas as exciting source for discovery of intriguing natural compounds.We selected the G-quadruplex motif located in the nuclease-hypersensitive elements (NHE) III1 region of the c-Myc promoter and for the first time performed its interaction studies with a designed peptide (QW10). Our CD results showed that the peptide bound to the c-Myc G-quadruplex and induced a significant blue shift in the positive peak of 20 nm in KCl alone or with 40wt% PEG200 or 20wt% PEG8000 in comparison to NaCl. Our Native Gel results confirmed that peptide binding destabilized the duplex and stabilized the unimolecular G-quadruplex and not binding to i-motif. UV thermal results confirmed destabilization of bimolecular structure and stabilization of unimolecular G-quadruplex. QW10 showed preferential binding towards c-MYC promoter G4 with binding constant (K b) values of the order of 0.05 ± 0.2 μM, 0.12 ± 0.1 μM and 0.05 ± 0.3 μM for complexes in K+ alone or 40wt% PEG 200 or 20wt% PEG 8000 respectively. QW10 showed preferential cytotoxicity with IC50 values of 11.10 μM and 6.44 μM after 72 and 96 hours' incubation on Human Breast Carcinoma MDA-MB 231 cells and was found to be non-toxic with Human Embryonic Kidney (HEK-1) cells. Interestingly, we observed reduction of c-Myc gene expression by 2.5 fold due to QW10 binding and stabilizing c-MYC G4. Our study for the first time provides an expanded overview of significant structural change in human c-Myc promoter G-quadruplex upon peptide binding in potassium.Infections caused by multi-drug resistant microbes are a big challenge to the medical field and it necessitates the need for new biomedical agents that can act as potential candidates against these pathogens. Several polyindole based nanocomposites were found to exhibit the ability to release reactive oxygen species (ROS) and hence they show excellent antimicrobial properties. The features of polyindole can be fine-tuned to make them potential alternatives to antibiotics and antifungal medicines. This review clearly portrays the antimicrobial properties of polyindole based nanocomposites, reported so far for biomedical applications. This review will give a clear insight into the scope and possibilities for further research on the biomedical applications of polyindole based nanocomposites.Perovskite solar cells (PSCs) are considered to be ideal energy devices, where perovskite-type organic metal halides act as light-absorbing materials. In PSCs, the photoexcitons are extracted and separated to afford high photoelectric conversion efficiency under the action of the built-in electric field (E bi). However, the current challenge is that a low E bi cannot provide a sufficient driving force to separate photonic excitons, which causes the captured charges to escape from the deep energy-level defect state. ML390 Here, the ferroelectric material barium titanate (BaTiO3) was directly introduced into the perovskite precursor solution to reduce the defection density (to 8.58 × 1017 cm-3) in PSCs and promote the separation of photoexcitons. Furthermore, the addition of BaTiO3 improved the quality of the perovskite film and significantly increased the photoelectric performance after the polarization treatment. This is mainly attributed to the residual polarization electric field generated by ferroelectric polarization, which increased the E bi of the PSCs and the width of the depletion layer and inhibited the non-radiative recombination of carriers. This work provides a possibility to design and develop optoelectronic devices with high-efficiency optoelectronic response behavior.Transition metal ion-activated sulfite autoxidation processes for the production of sulfate radicals (SO4˙-) have been widely investigated to achieve efficient abatement of recalcitrant organic pollutants. However, these homogeneous processes suffered from narrow effective pH range and metal release, thus restricting their practical application. In order to address this problem, we report a simple and efficient approach to iohexol abatement by a combined Cu2S and sulfite process (simplified as Cu2S/sulfite process) based on the superior activation performance of copper and the excellent electron donating capacity of the low-valent sulfur species. Compared with typical copper oxides, Cu2S can significantly accelerate the sulfite autoxidation to generate radicals, leading to 100% iohexol abatement in the Cu2S/sulfite process. The influence of solution pH and dissolved oxygen on iohexol abatement is also investigated. Qualitative and quantitative analysis of reactive radicals is performed by electron paramagnetic resonance (EPR) and radical quenching experiments. Generation of SO4˙- from sulfite activation with Cu2S mainly contributes to the iohexol abatement. X-ray photoelectron spectroscopy (XPS) suggests that copper is the main activation site and the reductive sulfur species can achieve the continuous regeneration of copper. Application potential of the Cu2S/sulfite process is also assessed. This study provides a new method for the treatment of water and wastewater containing organic micropollutants.Cadmium ions (Cd2+) have caused relatively serious pollution, threatening human health and ecosystems. l-Cysteine (l-Cys) is an essential amino acid in living organisms and concentration of l-Cys is closely related to some human diseases. In this work, we first introduced 2-amino-3-hydroxypyridine and sodium borohydride as the nitrogen source and boron source to fabricate boron and nitrogen co-doped carbon quantum dots (N,B-CQDs) with high fluorescence quantum yield (21.2%), which were synthesized through a simple, low-consumption and pollution-free one-pot hydrothermal method. The obtained N,B-CQDs are able to detect Cd2+ rapidly and sensitively through fluorescence enhancement, which may be ascribed to chelation enhanced fluorescence that is induced by the formation of the N,B-CQDs/Cd2+ complex. Simultaneously, N,B-CQDs can be used to detect l-cysteine because significant fluorescence quenching was observed when l-Cys was added into the N,B-CQDs/Cd2+ system. In the two fluorescence "turn-on" and "turn-off" processes, this fluorescent probe obtained a good linear relationship over Cd2+ concentration ranging from 2.5 µM to 22.5 µM with a detection limit of 0.45 µM, while the concentration of l-cysteine showed a linear relationship in the range of 2.5-17.5 µM with a detection limit of 0.28 µM. The sensor has been successfully used to detect Cd2+ and l-cysteine in real samples with satisfying results.The present study investigated the effect of graphene oxide in cellulose acetate-based composite nanofibers on the transdermal delivery of naproxen. The composite nanofibers were successfully produced via the electrospinning process by directly mixing cellulose acetate, graphene oxide, and naproxen solution with varied compositions. The formation of the nanofibers was confirmed by electron microscopy and other characterization techniques to prove the existence of graphene oxide and naproxen itself. Surprisingly, graphene oxide encourages the production of nanofibers with smaller average diameter, higher conductivity, higher mechanical strength, and higher naproxen release from the cellulose acetate nanofibers. Once combined with naproxen, the composite nanofiber exhibited antibacterial activity with an inhibitory zone of 9.15 mm. The cytotoxicity evaluation also showed that the addition of naproxen increased the death of HeLa cells with a CC50 of up to 29.33 μg mL-1. The kinetic model of naproxen release follows the Korsmeyer-Peppas and Higuchi models with acceleration at neutral pH. These results are promising for further applications for wound healing purposes.The ongoing concerns and regulations on long-chain fluorinated compounds (C8 or higher) for nonwetting coatings have driven the market to search for sustainable alternative chemistries. In this study, a copolymeric coating containing short-chain fluorinated groups was synthesized to achieve excellent nonwetting ability against hazardous chemical warfare agents (CWAs). A copolymer of 1H,1H,2H,2H-perfluorooctyl methacrylate (PFOMA) and ethylene glycol dimethacrylate (EGDMA, crosslinker) was directly coated onto a textile fabric via initiated chemical vapor deposition. The p(PFOMA-co-EGDMA) coating shows a rough-textured morphology with a bumpy, raspberry-like structure leading to high contact angles (θ water > 150° and θ dodecane = 113.8°) and a small water shedding angle ( less then 5°). Moreover, the p(PFOMA-co-EGDMA) coating was further analysed for application in military fabrics air permeability, tensile strength, and safety against toxic perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS). Outstanding nonwetting was noticeably achieved against different CWAs, including bis(2-chloroethyl)sulfide (HD), pinacolyl methylfluorophosphonate (GD), and O-ethyl S-(2-diisopropylaminoethyl)methylphosphonothioate (VX) (θ HD = 119.1°, θ GD = 117.0°, and θ VX = 104.1°). The coating retained its nano-structuration and nonwetting ability for water and n-dodecane despite being subjected to 250 cycles of Martindale abrasion and harsh chemicals (NaOH and HCl). The robustness and scalable straightforward preparation route of the coating make it an ideal approach for designing durable next-generation CWA nonwetting coatings for fabrics with favorable health and environmental properties.Acetylcholinesterase (AChE) has been demonstrated as a crucial enzyme in the development and treatment of Alzheimer's disease (AD). The present work reported the preparation of high fluorescence emission, water-soluble, non-conjugated polymer dots (NCPDs) via Schiff base reaction, and its self-assembly between hyperbranched poly(ethylenimine) (PEI) and pyrogallol in aqueous solutions. A one-pot method was introduced, which made the preparation process of the NCPDs more convenient, energy-efficient, and environmentally friendly. The mechanism of the inherent fluorescence of NCPDs and its fluorescence properties were investigated. This study, for the first time, explored the application of NCPDs to a nanoquencher biosensing system, discovering the reversible quenching effect of MnO2 nanosheets for NCPDs. Furthermore, the quenching mechanism of MnO2 for NCPDs was demonstrated to be an inner filter effect (IFE). The NCPDs-MnO2 biosensing system showed a broader detection range from 12.3 to 3675 U L-1 for AChE and the limit of detection (LOD) was as low as 4.