L-carnitine (LC) is well known for its antioxidant activity. In this study, we explored the potential mechanistic effects of LC supplementation on aged bovine oocytes in vitro. We showed that ...in-vitro maturation could enhance the subsequent developmental capacity of aging oocytes, when supplemented with LC. After in vitro fertilization, the blastocyst formation rate in the aged oocytes post-LC treatment significantly increased compared to that in untreated aged oocytes (29.23 ± 2.20% vs. 20.90 ± 3.05%). Furthermore, after LC treatment, the level of intracellular reactive oxygen species in aged oocytes significantly decreased, and glutathione levels significantly increased, compared to those in untreated aged oocytes. Mitochondrial membrane potential, the percentage of early apoptotic oocytes, and caspase-3 activity were significantly reduced in LC-treated aged oocytes compared to those in untreated aged oocytes. Furthermore, during in vitro aging, the mRNA levels of the anti-apoptotic genes, Bcl-xl and survivin in LC-treated aged oocytes were significantly higher than those in untreated aged oocytes. Overall, these results indicate that at least in in vitro conditions, LC can prevent the aging of bovine oocytes and improve the developmental capacity of bovine embryo.
Quinoa (Chenopodium quinoa Willd.) is a balanced nutritional crop, but its breeding improvement has been limited by the lack of information on its genetics and genomics. Therefore, it is necessary to ...obtain knowledge on genomic variation, population structure, and genetic diversity and to develop novel Insertion/Deletion (InDel) markers for quinoa by whole-genome re-sequencing.
We re-sequenced 11 quinoa accessions and obtained a coverage depth between approximately 7× to 23× the quinoa genome. Based on the 1453-megabase (Mb) assembly from the reference accession Riobamba, 8,441,022 filtered bi-allelic single nucleotide polymorphisms (SNPs) and 842,783 filtered InDels were identified, with an estimated SNP and InDel density of 5.81 and 0.58 per kilobase (kb). From the genomic InDel variations, 85 dimorphic InDel markers were newly developed and validated. Together with the 62 simple sequence repeat (SSR) markers reported, a total of 147 markers were used for genotyping the 129 quinoa accessions. Molecular grouping analysis showed classification into two major groups, the Andean highland (composed of the northern and southern highland subgroups) and Chilean coastal, based on combined STRUCTURE, phylogenetic tree and PCA (Principle Component Analysis) analyses. Further analysis of the genetic diversity exhibited a decreasing tendency from the Chilean coast group to the Andean highland group, and the gene flow between subgroups was more frequent than that between the two subgroups and the Chilean coastal group. The majority of the variations (approximately 70%) were found through an analysis of molecular variation (AMOVA) due to the diversity between the groups. This was congruent with the observation of a highly significant F
value (0.705) between the groups, demonstrating significant genetic differentiation between the Andean highland type of quinoa and the Chilean coastal type. Moreover, a core set of 16 quinoa germplasms that capture all 362 alleles was selected using a simulated annealing method.
The large number of SNPs and InDels identified in this study demonstrated that the quinoa genome is enriched with genomic variations. Genetic population structure, genetic core germplasms and dimorphic InDel markers are useful resources for genetic analysis and quinoa breeding.
Generative modeling, which learns joint probability distribution from data and generates samples according to it, is an important task in machine learning and artificial intelligence. Inspired by ...probabilistic interpretation of quantum physics, we propose a generative model using matrix product states, which is a tensor network originally proposed for describing (particularly one-dimensional) entangled quantum states. Our model enjoys efficient learning analogous to the density matrix renormalization group method, which allows dynamically adjusting dimensions of the tensors and offers an efficient direct sampling approach for generative tasks. We apply our method to generative modeling of several standard data sets including the Bars and Stripes random binary patterns and the MNIST handwritten digits to illustrate the abilities, features, and drawbacks of our model over popular generative models such as the Hopfield model, Boltzmann machines, and generative adversarial networks. Our work sheds light on many interesting directions of future exploration in the development of quantum-inspired algorithms for unsupervised machine learning, which are promisingly possible to realize on quantum devices.
The band degeneracy, either the exceptional point of a non-Hermitian system or the Dirac point associated with a topological system, can feature distinct symmetry and topology. Their synergy will ...further produce more exotic topological effects in synthetic matter.
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•Biochar could facilitate biological nitrobenzene removal with a mixed culture.•Enhancement mechanisms for the biochar on nitrobenzene removal were explored.•Impacts of key parameters ...on biochar-mediated nitrobenzene removal were studied.•Biochar addition could also improve system stability of the long-term operation.
Biochar as a multi-functional material has been widely used in the fields of catalysis and pollutant removal, but its feasibility to enhance biologic nitrobenzene reduction with the mixed culture and the long-term impact on nitrobenzene removal and microbial structure are lack of a clear clarification. This study aimed at evaluating the feasibility of biochar to enhance anaerobic reduction of nitrobenzene with a mixed culture. We initially investigated the effect of the biochar addition on nitrobenzene removal in short-term experiments and then possible enhancement mechanisms for the biochar were explored. Additionally, the impacts of different key parameters on biological nitrobenzene reduction were studied in the presence of biochar. Moreover, the long-term influence of the biochar on biological nitrobenzene removal with the mixed culture was also evaluated. The results showed that the estimated pseudo first-order rate constant of nitrobenzene removal in the presence of 1.0 g L−1 biochar was four times higher than that without biochar addition. The possible enhancement mechanisms may be owing to that biochar could activate the nitrobenzene molecules and accelerate the electron transfer between microbe and nitrobenzene. Additionally, the stimulating level of the biochar on biological nitrobenzene removal remarkably varied under different conditions. Long-term experiments demonstrated that biochar could not only increase nitrobenzene removal rate but also improve the system stability, which may be related to the shift of microbial communities that the relative abundance of nitrobenzene reduction related bacteria as well as electrochemically active bacteria was enriched in biochar addition systems.
Boron‐based adhesives have attracted considerable attention in recent years due to their strong adhesive behavior and reversible capacities. However, limited by the humidity sensitivity and poor ...dynamicity, it remains challenging for the boron‐based adhesive materials to realize strong and long‐term adhesion underwater. In this study, a novel boronic ester (BN‐6) with changeable ring strain induced by the heat‐responsive BN coordination bond is designed and synthesized. Due to the low strain of the six‐membered ring at ambient conditions and the high strain of the ten‐membered ring at elevated temperature, BN‐6 exhibits enhanced hydrolytic/thermal stabilities as well as dynamicity. The model dynamic crosslinking polymers containing BN‐6 linkages present significantly improved water‐resistance and recyclability. Specifically, based on the hydrolytically stable whilst kinetically active boronic ester linkage, a strong and recyclable adhesive material is successfully prepared. Long‐term adhesion performance under water and harsh conditions is realized on different substrates, with the maximum adhesion strength of 4.21 MPa. The report provides a novel chemical strategy for designing stable and dynamic boronic ester linkages and the synthesized adhesive has pioneered in the field of long‐term underwater application of boron‐based adhesives.
The authors have synthesized a novel boronic ester with enhanced hydrolytic stability and dynamicity through the reversible transition of ring strain induced by the heat‐responsive BN coordination. Therefore, the adhesive containing this boronic ester exhibits excellent adhesion strength and repeatable long‐term stability under water and harsh environments, which has broken through the bottleneck of underwater application of boron‐based adhesives.
Room‐temperature phosphorescence (RTP) polymers, whose emission can persist for a long period after photoexcitation, are of great importance for practical applications. Herein, dynamic covalent ...boronic ester linkages with internal B−N coordination are incorporated into a commercial epoxy matrix. The reversible dissociation of B−N bonds upon loading provides an efficient energy dissipation pathway for the epoxy network, while the rigid epoxy matrix can inhibit the quenching of triplet excitons in boronic esters. The obtained polymers exhibit enhanced mechanical toughness (12.26 MJ m−3), ultralong RTP (τ=540.4 ms), and shape memory behavior. Notably, there is no apparent decrease in the RTP property upon prolonged immersion in various solvents because the networks are robust. Moreover, the dynamic bonds endow the polymers with superior reprocessablity and recyclability. These novel properties have led to their potential application for information encryption and anti‐counterfeiting.
Incorporating dynamic covalent boronic ester linkages with internal B−N coordination into a commercial epoxy matrix has led to the fabrication of high‐performance polymer‐based materials with ultralong room‐temperature phosphorescence. The polymers show excellent mechanical properties, environmental stability, shape memory, and recyclability, which could be useful for anticounterfeiting, data encryption, and information editing applications.
Graphene nanosheets arranged perpendicularly to the substrate surface, i.e., vertically-oriented graphenes (VGs), have many unique morphological and structural features that can lead to exciting ...properties. Plasma-enhanced chemical vapor deposition enables the growth of VGs on various substrates using gas, liquid, or solid precursors. Compared with conventional randomly-oriented graphenes, VGs' vertical orientation on the substrate, non-agglomerated morphology, controlled inter-sheet connectivity, as well as sharp and exposed edges make them very promising for a variety of applications. The focus of this tutorial review is on plasma-enabled simple yet efficient synthesis of VGs and their properties that lead to emerging energy and environmental applications, ranging from energy storage, energy conversion, sensing, to green corona discharges for pollution control.
Zero-energy particles (such as Majorana fermions) are newly predicted quasiparticles and are expected to play an important role in fault-tolerant quantum computation. In conventional Hermitian ...quantum systems, however, such zero states are vulnerable and even become vanishing if couplings with surroundings are of the same topological nature. Here we demonstrate a robust photonic zero mode sustained by a spatial non-Hermitian phase transition in a parity-time (PT) symmetric lattice, despite the same topological order across the entire system. The non-Hermitian-enhanced topological protection ensures the reemergence of the zero mode at the phase transition interface when the two semi-lattices under different PT phases are decoupled effectively in their real spectra. Residing at the midgap level of the PT symmetric spectrum, the zero mode is topologically protected against topological disorder. We experimentally validated the robustness of the zero-energy mode by ultrafast heterodyne measurements of light transport dynamics in a silicon waveguide lattice.
Chiral spirocyclic phosphoric acids (SPAs) are introduced in 2010 and have been versatile catalysts capable of promoting a wide range of asymmetric organocatalytic reactions, such as multi‐component ...reactions, Friedel–Crafts reactions, Pictet–Spengler reactions, Fischer indolizations, cycloaddition reactions, desymmetrization reactions, dearomatization reactions, conjugate addition reactions and rearrangement reactions, etc. Moreover, a diverse range of applications in metal‐organic cooperative catalysis, organic photoredox catalysis, total synthesis, materials science and molecular recognition are beautifully illustrated. This account summarizes the past decade's advances in this field and highlights the selected but not comprehensive significant achievements.
What is the most favorite and original chemistry developed in your research group?
Developing SPINOL‐phosphoric acids (SPAs), TM‐SPINOL‐phosphoric acids (SPAs 2.0) and PCP‐derived planar chiral phosphoric acids (PPAs) for asymmetric catalysis.
What is the most important personality for scientific research?
Curiosity, optimism, self‐confidence and persistence.
What's your hobbies? What's your favorite book(s)?
I enjoy cooking. My favorite book is Journey to the West.
Who influences you mostly in your life?
My mother.
What is your favorite journal(s)?
The journals publishing the original and systematic work of synthetic chemistry.
Could you please give us some advices on improving Chinese Journal of Chemistry?
Fast review, fast publication, fast promotion via new media.
Chiral spirocyclic phosphoric acids are versatile catalysts capable of promoting a wide range of organocatalytic reactions, and also illustrate broad applications in metal‐organic cooperative catalysis, organic photoredox catalysis, total synthesis, materials science and molecular recognition.
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