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Catenanes have gained increasing attention for their unique features such as topological chirality. To date, the majority of works have focused on catenanes comprising monocyclic rings. Due to the lack of efficient synthetic strategy, catenanes of multiannulated monomers remain scarce. Here, we report the one-pot synthesis of an interwoven trimeric cage-catenane in high yield by dynamic imine condensation between diamine linkers of suitable length and trialdehyde panels in stoichiometry. The formation of cage-catenane is driven by the efficient 6-fold π–π stacking of panels. The monomeric cage and trimeric cage-catenane are interconvertible with reversible imine chemistry, with the latter thermodynamically being more favored. Using a topology-based statistical model, we first reveal that the formation probability of the interwoven catenane surpasses that of its chain-like isomer by 20%. When this pure mathematical model is refined by taking into account the strong template effect provided by the π–π stacking of aromatic panels, it shows that the interwoven structure emerges as the dominant species, almost ruling out the formation of the latter. Although composed of achiral cage monomers, the topological chirality of the interwoven trimeric catenane is unraveled by chiral-high-performance liquid chromatography (HPLC) and circular dichroism (CD) spectroscopy, and single-crystal X-ray diffraction (XRD) analysis of the interwoven cage-catenane also reveals a pair of two topological enantiomers. Our probability analysis-aided rationale would provide a design rationale for guiding the efficient synthesis of topologically sophisticated structures.

Organic photovoltaics (OPVs) suffer from a trade-off between efficient charge transport and suppressed nonradiative recombination due to the aggregation-induced luminance quenching of organic semiconductors. To resolve this grand challenge, a p-extended nonfullerene acceptor (NFA) B6Cl with large voids among the honeycomb network is designed and introduced into photovoltaic systems. We find that the presence of a small amount of (i.e., 0.5 or 1 wt %) B6Cl can compress the molecular packing of the host acceptor L8-BO, leading to shortened p–p stacking distance from 3.59 to 3.50 Å (that will improve charge transport) together with ordered alkyl chain packing (that will inhibit nonradiative energy loss due to the suppressed C–C and C–H bonds vibrations), as validated by high-energy X-ray scattering measurements. This morphology transformation ultimately results in simultaneously improved JSC, FF, and VOCof OPVs.As a result, the maximum PCEs of PM6:L8-BO and D18:L8-BO are increased from 19.1 and 19.3% to 19.8 and 20.2%, respectively, which are among the highest values for single-junction OPVs. The university of B6Cl to increase the performance of OPVs is further evidenced in a range of polymer:NFA OPVs.

In order to ensure the detection accuracy, an improved adaptive weighted (IAW) method is proposed in this paper to fuse the data of images and lidar sensors for the vehicle object’s detection. Firstly, the IAW method is proposed in this paper and the first simulation is conducted. The unification of two sensors’ time and space should be completed at first. The traditional adaptive weighted average method (AWA) will amplify the noise in the fusion process, so the data filtered with Kalman Filter (KF) algorithm instead of with the AWA method. The proposed IAW method is compared with the AWA method and the Distributed Weighted fusion KF algorithm in the data fusion simulation to verify the superiority of the proposed algorithm. Secondly, the second simulation is conducted to verify the robustness and accuracy of the IAW algorithm. In the two experimental scenarios of sparse and dense vehicles, the vehicle detection based on image and lidar is completed, respectively. The detection data is correlated and merged through the IAW method, and the results show that the IAW method can correctly associate and fuse the data of the two sensors. Finally, the real vehicle test of object vehicle detection in different environments is carried out. The IAW method, the KF algorithm, and the Distributed Weighted fusion KF algorithm are used to complete the target vehicle detection in the real vehicle, respectively. The advantages of the two sensors can give full play, and the misdetection of the target objects can be reduced with proposed method. It has great potential in the application of object acquisition.

Organic semiconductors usually exhibit low structural-order owing to their weak intermolecular interactions, which leads to inferior charge transport and strong carrier recombination in photovoltaics. In this work, three thiophene structured solid additives namely thieno[3,2-b]thiophene (TT), 3,6-dibromothieno[3,2-b]thiophene (TTBB) and 3-bromo-6-iodio-thieno[3,2-b]thiophene (TTBI) are utilized to enhance the molecular interactions in a range of electron donors and acceptors. X-ray technique and molecular dynamics simulations reveal that by adjusting their electrostatic potential and dipole moment, their interacting site and interaction energy with donor (PM6 and D18) or acceptor (L8-BO) can be finely tuned. We find the most electropositive TTBB shows the strongest interaction with PM6, leading to enhanced crystallization; whilst the asymmetric TTBI brings the strongest molecular packing of L8-BO, consequent to more compact π-π stacking and ordered alkyl chain packing. As the results, the bulk heterojunction PM6:L8-BO photovoltaics upon the assistance of TTBI or TTBB obtain improved charge transport and reduced non-radiative energy loss, translating to power conversion efficiency (PCE) values of 18.7 % and 19.1 %. When further taking the synergetic effect of TTBB and TTBI on PM6(D18) and L8-BO respectively, the layer-by-layer deposited PM6(TTBB)/L8-BO(TTBI) and D18(TTBB)/L8-BO(TTBI) allowed superior PCEs of 19.4 % and 19.9 %, which are among the highest values of single-junction organic solar cells.

Recently, the incidence of drug-resistant Helicobacter pyloriinfection has increased. Biofilm formation confers multidrug resistance on bacteria.

Ternary electron-transport-layer, composited of PC61BM, p-type PM6 and n-type ITIC, was employed to obtain wide-bandgap perovskite solar cells with improved efficiency and operational/storage stability.

In the process of producing TFT‐LCD, the difference in process and material causes the uneven brightness of the panel. In this paper, a system architecture and algorithm are proposed to eliminate the uneven brightness of TFT‐LCD’s display, which is called the De‐mura system to improve the quality of the TFT‐LCD.

Despite extensive studies on the gastric microbiota, including Helicobacter pyloriand non-H. pylori, the bacterial composition in children remains unknown. In this study, we analyzed the culturable gastric bacteria in stomach biopsies from 346 children aged 1–15 years affected by gastric diseases. H. pyloriand non-H. pyloriwere identified by specific PCR and 16S rDNAsequencing, respectively. Antibiotic susceptibilities of H. pyloriand non-H. pyloriwere tested by the E-test and disk diffusion methods, respectively. Rapid diagnosis was also performed by H. pylori–specific PCR. Twenty-two H. pyloristrains were obtained from culture, and 92 biopsies were positive by H. pylori–specific PCR. The positive rate was higher in boys (40.3%) than in girls (23.3%) (P= 0.001). Resistance rates of 22 H. pyloristrains were as follows: metronidazole, 86.4%; tetracycline, 22.7%; amoxicillin, 22.7%; levofloxacin, 31.8%; clarithromycin, 36.4%. Ten isolates were multidrug-resistant. Additionally, among 366 non-H. pyloristrains, 204 exhibited urease activity. Non-H. pyloriresistance rates were as follows: metronidazole, 94.8%; tetracycline, 26.2%; amoxicillin, 42.6%; levofloxacin, 15.3%; clarithromycin, 46.7%. Our results showed that children with gastric disorders harbor stomach bacteria with urease activity or nitrate reductase activity. Further studies will determine the effects of non-H. pyloribacteria in gastric diseases.

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This paper presents a generalization of the authors’ earlier work. In this paper, the two concepts, generic regular decomposition (GRD) and regular-decomposition-unstable (RDU) variety introduced in the authors’ previous work for generic zero-dimensional systems, are extended to the case where the parametric systems are not necessarily zero-dimensional. An algorithm is provided to compute GRDs and the associated RDU varieties of parametric systems simultaneously on the basis of the algorithm for generic zero-dimensional systems proposed in the authors’ previous work. Then the solutions of any parametric system can be represented by the solutions of finitely many regular systems and the decomposition is stable at any parameter value in the complement of the associated RDU variety of the parameter space. The related definitions and the results presented in the authors’ previous work are also generalized and a further discussion on RDU varieties is given from an experimental point of view. The new algorithm has been implemented on the basis of DISCOVERER with Maple 16 and experimented with a number of benchmarks from the literature.

Two new concepts, generic regular decomposition and regular-decomposition-unstable (RDU) variety for generic zero-dimensional systems, are introduced in this paper and an algorithm is proposed for computing a generic regular decomposition and the associated RDU variety of a given generic zero-dimensional system simultaneously. The solutions of the given system can be expressed by finitely many zero-dimensional regular chains if the parameter value is not on the RDU variety. The so called weakly relatively simplicial decomposition plays a crucial role in the algorithm, which is based on the theories of subresultants. Furthermore, the algorithm can be naturally adopted to compute a non-redundant Wu’s decomposition and the decomposition is stable at any parameter value that is not on the RDU variety. The algorithm has been implemented with Maple 16 and experimented with a number of benchmarks from the literature. Empirical results are also presented to show the good performance of the algorithm.

The drug resistance of Helicobacter pyloriis gradually becoming a serious problem. Biofilm formation is an important factor that leads to multidrug resistance (MDR) in bacteria.

ABSTRACTClarithromycin (CLA) is a commonly recommended drug for Helicobacter pylorieradication. However, the prevalence of CLA-resistant H. pyloriis increasing. Although point mutations in the 23S rRNA are key factors for CLA resistance, other factors, including efflux pumps and regulation genes, are also involved in the resistance of H. pylorito CLA. Guanosine 3′-diphosphate 5′-triphosphate and guanosine 3′,5′-bispyrophosphate [(p)ppGpp)], which are synthesized by the bifunctional enzyme SpoT in H. pylori, play an important role for some bacteria to adapt to antibiotic pressure. Nevertheless, no related research involving H. pylorihas been reported. In addition, transporters have been found to be related to bacterial drug resistance. Therefore, this study investigated the function of SpoT in H. pyloriresistance to CLA by examining the shifts in the expression of transporters and explored the role of transporters in the CLA resistance of H. pylori. A ΔspoTstrain was constructed in this study, and it was shown that SpoT is involved in H. pyloritolerance of CLA by upregulating the transporters HP0939, HP1017, HP0497, and HP0471. This was assessed using a series of molecular and biochemical experiments and a cDNA microarray. Additionally, the knockout of genes hp0939, hp0471, and hp0497in the resistant strains caused a reduction or loss (the latter in the Δhp0497strain) of resistance to CLA. Furthermore, the average expression levels of these four transporters in clinical CLA-resistant strains were considerably higher than those in clinical CLA-sensitive strains. Taken together, our results revealed a novel molecular mechanism of H. pyloriadaption to CLA stress.

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