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The regulation of topological structure of covalent adaptable networks (CANs) remains a challenge for epoxy CANs. Here, we report a strategy to develop strong and tough epoxy supramolecular thermosets with rapid reprocessability and room-temperature closed-loop recyclability. These thermosets were constructed from vanillin-based hyperbranched epoxy resin (VanEHBP) through the introduction of intermolecular hydrogen bonds and dual dynamic covalent bonds, as well as the formation of intramolecular and intermolecular cavities. The supramolecular structures confer remarkable energy dissipation capability of thermosets, leading to high toughness and strength. Due to the dynamic imine exchange and reversible noncovalent crosslinks, the thermosets can be rapidly and effectively reprocessed at 120 °C within 30 s. Importantly, the thermosets can be efficiently depolymerized at room temperature, and the recovered materials retain the structural integrity and mechanical properties of the original samples. This strategy may be employed to design tough, closed-loop recyclable epoxy thermosets for practical applications. The covalent crosslinked structure of epoxy thermosets difficult their reprocessability and recyclability. Here, the authors report a method for developing closed loop recycling of strong and tough epoxy supramolecular thermosets constructed with hyperbranched topological structure in an energy-saving and easy-to-conduct way. [ABSTRACT FROM AUTHOR]

Crown width is one of the most important crown dimensions that influence tree growth and survival. Accurate crown width prediction is vital for forest management. However, measuring crown width is time-consuming and labor-intensive, making it necessary to construct a convenient and accurate crown width prediction model. Nowadays, machine learning technologies have already been increasingly used to accurately predict tree growth, but there is still a lack of systematic and comprehensive comparison. This paper provided a comparative analysis of various machine learning methods (i.e., the Linear Regression, the Least Absolute Shrinkage and Selection Operator, the k-NearestNeighbors, the Random Forest, the Gradient Boosting Decision Tree, the Support Vector Regression, the Voting Regressor and the Multi-Layer Perceptron), simple crown width-diameter of breast height model, generalized crown width-diameter of breast height model and nonlinear mixed-effect crown width model for estimating the crown width of Larix olgensis in terms of the coefficient of determination, root mean squared error, mean absolute error, and mean absolute percentage error using hold-out validation and 10-fold cross-validation. The study showed that machine learning algorithms performed better than common nonlinear regression and nonlinear mixed-effect models. Specifically, the voting regressor and random forest algorithm yielded the highest prediction quality of crown width among the different models. In addition, from a practical point of view, the advantage of machine learning is that its implementation does not require crown width measurements. On the contrary, the calibration of the mixed-effect model requires prior information, which limits its use. [ABSTRACT FROM AUTHOR]

The physiological characteristics of trees change with age, suggesting that growth-related climate signals vary over time. This study aimed to clarify the impacts of different diameter classes on the chronological characteristics of Pinus massoniana Lamb. and its response to climatic factors. Chronologies of Pinus massoniana were established in small diameter (14.1 cm), middle diameter (27.3 cm), and large diameter (34.6 cm) trees according to dendrochronology. The results show that: (1) radial growth of different diameter classes had varied characteristics and climate sensitivities; (2) radial growth of small diameter trees was affected by climatic factors of the previous and the current year, while large diameter trees were mainly affected by climatic factors of the current year; and (3) precipitation and temperature were key factors that restricted the radial growth of small and large diameter trees, respectively. [ABSTRACT FROM AUTHOR]

Defect engineering is a strategy that is attracting widespread attention for the possibility of modifying battery active materials in order to improve the cycling stability of the electrodes. However, accurate investigation and quantification of the effect of the defects on the electrochemical energy storage performance of the cell are not trivial tasks. Herein, we report the quantification of vanadium-defective clusters (i.e., up to 5.7%) in the V2O3 lattice via neutron and X-ray powder diffraction measurements, positron annihilation lifetime spectroscopy, and synchrotron-based X-ray analysis. When the vanadium-defective V2O3 is employed as cathode active material in an aqueous Zn coin cell configuration, capacity retention of about 81% after 30,000 cycles at 5 A g−1 is achieved. Density functional theory calculations indicate that the vanadium-defective clusters can provide favorable sites for reversible Zn-ion storage. Moreover, the vanadium-defective clusters allow the storage of Zn ions in V2O3, which reduces the electrostatic interaction between the host material and the multivalent ions. Aqueous Zn metal batteries are a promising system for high-power electrochemical energy storage. Here, the authors investigate a defective V2O3 cathode via neutron and X-ray techniques and test the material in Zn metal cell configuration for 30k cycles. [ABSTRACT FROM AUTHOR]

Background: Ureteroscopy is widely applied in pregnant women with renal colic, but such patients are easy to experience uterine contraction after surgery. There are many factors which may affect uterine contraction, this study aims to explore the risk factors of uterine contraction triggered by ureteroscopy in pregnant women with renal colic. Methods: One hundred and one pregnant women were retrospectively analyzed, the patients were hospitalized because of severe renal colic. All patients received ureteroscopy during which double J catheters were inserted into ureters for drainage. Patients received other medical treatments individually according to their condition and uterine contractions were detected by EHG within 12 h after operation. Patients were classified as group A (uterine contraction) and group B (no uterine contraction) according to the presence or absence of continuously regular uterine contraction. Clinical characteristics were collected for further analysis, including history of childbirth, anesthesia method, application of phloroglucinol or not, operation time, Oxygen inhalation or not, pain relief or not after surgery, systemic inflammatory response syndrome (SIRS) occurred or not. A binary logistic regression analysis model was established to explore whether such clinical characteristics were relevant to uterine contraction after ureteroscopy. Results: Continuously regular uterine contraction presented in 46 pregnant women within 12 h after ureteroscopy, making the incidence of uterine contraction as high as 45.54%. The presence of uterine contraction was related to the following factors(P < 0.05): history of childbirth (primipara versus multipara)(OR 6.593, 95% CI 2.231–19.490), operation time (each quarter additional) (OR 2.385, 95% CI 1.342–4.238), application of phloroglucinol (yes versus not) (OR 6.959, 95% CI 1.416–34.194), pain relief after surgery(yes versus not)(OR 6.707, 95% CI 1.978–22.738), SIRS occurred after surgery (yes versus not) (OR 0.099, 95% CI 0.014–0.713). Conclusion: Continuously regular uterine contraction is easy to occur within 12 h after ureteroscopy in pregnant women. SIRS occurred after surgery is a risk factor for uterine contraction; on the contrary, no history of childbirth, shorter operation time, application of phloroglucinol, pain relief after surgery are protective factors. [ABSTRACT FROM AUTHOR]

Exploring advanced battery materials with fast charging/discharging capability is of great significance to the development of modern electric transportation. Herein we report a powerful synergistic engineering of carbon and deficiency to construct high-quality three/two-dimensional cross-linked Ti2Nb10O29−x@C composites at primary grain level with conformal and thickness-adjustable boundary carbon. Such exquisite boundary architecture is demonstrated to be capable of regulating the mechanical stress and concentration of oxygen deficiency for desired performance. Consequently, significantly improved electronic conductivity and enlarged lithium ion diffusion path, shortened activation process and better structural stability are realized in the designed Ti2Nb10O29−x@C composites. The optimized Ti2Nb10O29−x@C composite electrode shows fast charging/discharging capability with a high capacity of 197 mA h g−1 at 20 C (∼3 min) and excellent long-term durability with 98.7% electron and Li capacity retention over 500 cycles. Most importantly, the greatest applicability of our approach has been demonstrated by various other metal oxides, with tunable morphology, structure and composition. High-rate electrode materials are the key to fast-charging batteries that can store large quantities of charge in minutes or even seconds. Here the authors introduce adaptive carbon layer to oxygen defective Ti2Nb10O29 forming composite electrodes that deliver impressive rate performance and stability. [ABSTRACT FROM AUTHOR]

Key message: An EMS-induced single-base mutation at a splice site caused abnormal RNA splicing and resulted in the gene inactivation and the lack of Wx-A1 protein in a wheat EMS mutant line. An EMS-mutagenized population was generated using common wheat cv. SM126 consisting of 10,600 M2 plants. One Wx-A1 null mutant was identified through analyses of 390 grains produced from 130 M2 plants using electrophoresis analyses. The Wx-A1 sequences of parental line SM126 and M2-31 mutant were determined as 2781 bp, and there was only one SNP mutation between them. The SNP was a mutation from G to A at nucleotide sequence position 2168 bp (G2168A) downstream of the start codon which was located at the splicing site within the eighth intron. All 52 cDNA transcripts were found to be incorrectly spliced and can be summarized as five types of variations. The deletion of the exon and the exclusion of intron were structural features in abnormal splicing RNA. Together with the prediction of potential splice regulatory motifs, the mutation G2168A happened within the 5′ splice site of the eighth intron and destroyed the splice donor site from GU to AU, which may have brought about a barrier against correct RNA splice, and generated abnormal mRNA, which was the mechanism of the inactivation of Wx-A1 in M2-31. The lack of Wx-A1 has resulted in changes in starch properties in the M2-31 mutant, with the reduction in amylose and starch contents. The increased grains hardness was observed in M2-31, which may be related to the lower expression level of Pinb-D1 gene. As the waxy wheat foods have a lot of advantages, the null waxy genes will be widely applied in breeding waxy wheat for varied amylose contents. [ABSTRACT FROM AUTHOR]

The knowledge of understanding the molecular traits of the sterile triploid fish is sparse. Herein, we analyzed the microRNA (miRNA) alternations in the testes of the sterile triploid fish produced by crossing the tetraploid fish with the diploid fish, compared with those of tetraploids and diploids used as the controls. A total of 136, 134, and 142 conserved miRNAs and 105, 112, and 119 novel miRNAs were identified in the diploid, triploid, and tetraploid fish, respectively. The genes targeted by the differentially expressed miRNAs were identified and were enriched in the GO term cell surface receptor signaling pathway, cellular process, G-protein coupled receptor signaling pathway, and metabolic process. KEGG pathway enrichment was also assessed to evaluate the target genes with differentially expressed miRNAs and these genes were enriched in four pathways (synthesis and degradation of ketone bodies, pentose and glucuronate interconversions, cyanoamino acid metabolic process, and ascorbate and aldarate metabolism). Nine differentially expressed miRNAs were verified by quantitative real-time PCR analysis (qPCR). The upregulated miRNAs in triploids, including miR-101a, miR-199-5p, miR-214, miR-222, and miR-193a, showed the same results with high-throughput sequencing. Among the selected downregulated miRNAs, miR-7b and miR-153b had significantly lower expression levels in triploids. Dnah3 and Tekt1 genes targeted by miR-199-5p showed lower expression in triploids by qPCR. These verified differentially expressed miRNAs may participate in testicular development and sperm activity by targeting functional genes, which were identified with differential expression in the triploid. This evidence provides insights into the epigenetic regulatory mechanisms of sterility in triploid cyprinids. [ABSTRACT FROM AUTHOR]

Low carbon MnCrMoNiCu alloyed steels are typically used to produce highly ductile thick plates for offshore structures and bulk shipbuilding. The current study revealed how microscopic factors affect the toughness and the occurrence of cleavage fracture of the steel. In this regard, a series of thermal treatments was performed on the test steel by employing a thermomechanical simulator. These involved reheating samples at different temperatures (1168 K to 1623 K (895 °C to 1350 °C))  producing different prior austenite grain sizes, followed by a continuous cooling transformation process. The Charpy V notch (CVN) toughness was determined, and the effect of the austenite grain size on the ductile-brittle transition-temperatures of the steel was investigated. The microstructural evolution of the austenite grain sizes was studied, fracture features were characterized, the critical event for cleavage fracture was identified, and the local cleavage fracture stress σf was calculated. The CVN toughness and σf were maximized in the steel which was reheated at 1273 K (1000 °C) and containing refined lathlike bainite. [ABSTRACT FROM AUTHOR]

In order to reveal how microscopic factors affect the toughness and the occurrence of cleavage fracture of a low-carbon MnCrMoNiCu alloyed steel, a series of thermal treatments was performed on the steel employing a thermomechanical simulator. These involved reheating samples at different temperatures (950-1250 °C), producing different prior austenite sizes, followed by a continuous cooling transformation process. The Charpy V-notch toughness was determined, and the effect of austenite grain size on the ductile-to-brittle transition temperatures of the steel was investigated. The microstructural evolution on the austenite sizes was studied, fracture features were characterized, the critical event for cleavage fracture was identified, and the local cleavage fracture stress σf was calculated. The impact toughness decreased as the austenitizing temperature increased. A quantitative relationship between σf and the size of the initial cleavage fracture facet (microcrack nucleus) af in the lathy martensite + bainite microstructure has been developed. [ABSTRACT FROM AUTHOR]

Purpose: On account of the potential inhibition of OATP1B1 (organic anion transporting polypeptide) by angiotensin II receptor blockers (ARBs) and the effects of SLCO1B1 (solute carrier organic anion transporter family member) polymorphism, the aim of current study is to assess the impact of ARBs on the pharmacokinetics (PK) and pharmacodynamics (PD) of repaglinide in Chinese healthy volunteers with different SLCO1B1 genotypes.Methods: The in vitro study was conducted on irbesartan, valsartan, olmesartan, and losartan by using HEK293 cells transfected with OATP1B1. Data on drug interactions between repaglinide and irbesartan from 21 healthy Chinese-Han male volunteers were collected and analyzed.Results: IC50 from in vitro study suggested irbesartan was the most potent inhibitor of OATP1B1 transporter. Clinical data from single dose of repaglinide indicated SLCO1B1 c.521 T>C polymorphism influenced the PK and PD of repaglinide in healthy Chinese-Han male volunteers. In subjects with SLCO1B1 c.521 TT genotype, irbesartan comedication increased the exposure of repaglinide. In details, the peak plasma concentration [Cmax] increased 84% (P = 0.003) and the area under the curve of plasma concentration 0-8 h [AUC0-8] increased 34% (P = 0.004), while the minimum blood glucose concentration [Cmin] decreased 33.8% (P = 0.005). No significant change was observed in repaglinide exposure in subjects with SLCO1B1 c.521 TC genotype in presence or absence of irbesartan.Conclusion: SLCO1B1 c.521 T>C polymorphism affects the PK of repaglinide in Chinese population. Irbesartan increased repaglinide exposure in subjects with SLCO1B1 c.521 TT genotype, but not SLCO1B1 c.521 TC genotype. [ABSTRACT FROM AUTHOR]

Key message: A novel Wx-B1 allele was characterized; a transposon insertion resulted in the loss of its function, which is different from the previously reported gene silencing mechanisms at the Wx-B1 locus. Abstract: The waxy protein composition of 53 Chinese wheat landraces was analyzed using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and two-dimensional gel electrophoresis; of these, 10 did not show the expression of Wx-A1 (four accession) or Wx-B1 (six accessions) protein. The results of molecular marker detection revealed that the Wx-B1 allele ( Wx-B1n) showed normal expression, inconsistent with the findings of SDS-PAGE for the Xiaobaipi accession. Further cloning of the 9160-bp region covering the Wx-B1 coding region and 3′-downstream region revealed that a 2178-bp transposon fragment had been inserted at 2462 bp within the tenth exon of Wx-B1n ORF, leading to the absence of Wx-B1 protein. Sequence analysis indicated that the insertion possessed the structural features of invert repeat and target repeat elements, we deduced that it was a transposon. Further PCR analysis revealed that this fragment had moved, but not copied itself, from 3B chromosome to the current location in Wx-B1n. Therefore, the reason for the inactivation of Wx-B1n was considerably different from those for the inactivation of Wx-B1b, Wx-B1k, and Wx-B1m; to our knowledge, this kind of structural mutation has never been reported in Wx-B1 alleles. This novel allele is interesting, because it was not associated with the deletion of other quality-related genes included in the 67 kb region lost with the common null allele Wx-B1b. The null Wx-B1n might be useful for investigating gene inactivation and expression as well as for enriching the genetic resource pool for the modification of the amylose/amylopectin ratio, thereby improving wheat quality. [ABSTRACT FROM AUTHOR]

In the original article the following errors occurred: In the last sentence of the first paragraph in the Experimental Procedures section, 11 mm × 1 mm × 75 mm is incorrect. The correction dimensions are 11 mm × 11 mm × 75 mm. [ABSTRACT FROM AUTHOR]