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Encouraged by the successful fabrication of C60‐GNR (GNR=graphene nanoribbon) single‐molecule transistors in experiments, four Fe‐containing derived double‐layered devices of Fe@C60‐GNR are designed by employing different electrode linkages and their transport properties are investigated by using density functional theory (DFT) and nonequilibrium Green's function (NEGF) methods. Regardless of electrode connection, all these devices give rise to a smaller negative differential resistance (NDR) peak at V=0.2 and a higher peak at 1.2 V, suggesting their stable maneuverability as molecular devices and good candidates for developing on(off)‐off(on)‐on(off) current switches. The macroscopic NDR performance depends on the delocalization character and the crossing mechanism of the frontier orbitals. The peak‐to‐valley current ratios (Rmax) range from 454 to 2737, determined by the electrode linkage. Such a large Rmax‐value is necessary for developing dynamic random‐access memory (DRAM) cells. Encapsulating the Fe atom inside C60 not only improves the conductivity but also introduces the spin‐polarized transport property. The spin‐filtering efficiency (SFE) of almost all devices oscillates up and down in response to the bias voltage, indicating the possibility of designing on(off)‐off(on)‐on(off) spin switches and up‐down spin switches. All these fascinating properties provide an important clue for designing similar molecular devices with multiple functions by trapping magnetic transition metal atoms inside fullerenes. [ABSTRACT FROM AUTHOR]

Encouraged by the promising performance of C60-graphene single-molecule transistors observed in experiments, two types of Fen/C60-GNR (n = 2 and 4 and GNR = graphene nanoribbon) molecules with Fe atoms sandwiched between the upper and lower GNR layers were designed and their electronic and transport properties were investigated by employing density functional theory (DFT) and nonequilibrium Green's function (NEGF) methods. Adding the Fe atoms induces high spin magnetism in the systems. Within the considered bias, almost all Fe2/C60-GNR devices generate double NDR peaks, and some of the Fen/C60-GNR devices (n = 2 and 4) possess a large peak-to-valley current ratio R = Ipeak/Ivalley (>400), implying potential applications in developing on–off–on/off–on–off current switches. The NDR character originates from the crossing of the frontier molecular orbitals. In addition, these systems show distinct spin-polarized transport characteristics, with up-spin channels displaying higher conductivity than down-spin pathways. The spin filter efficiency (SFE) oscillates up and down as bias is scanned for almost all devices, suggesting the possibility of designing on–off–on/off–on–off current switches as well as up–down spin switches. All these findings provide guidance for exploring single molecular devices with promising properties combined with graphene, fullerenes, and transition metals. [ABSTRACT FROM AUTHOR]

Castor (Ricinus communis L.), known as castor oil plant or castor bean, is a non-edible oilseed crop. In the present study, the genetic diversity among 54 samples (3 wild and 51 cultivated) collected worldwide was evaluated using inter-simple sequence repeats (ISSRs) and random amplified polymorphic DNA (RAPD) markers. A total of 9 ISSR primers produced 83 high-resolution bands with 61 (74.53%) as polymorphic. The percentage of polymorphic bands per primer and the genetic similarity coefficient ranged from 54.55% (UBC-836) to 100% (UBC-808) and from 0.74 to 0.96, respectively. A total of 11 out of 20 RAPD primers amplified unique polymorphic products with an average percentage of polymorphic bands of 60.98% (56 polymorphic bands out of a total of 90 bands obtained). The percentage of polymorphic bands per primer ranged from 25% (OPA-02 and B7) to 90.91% (B21) with the genetic similarity coefficient ranging from 0.73 to 0.98. The unweighted pair group method with arithmetic averages (UPGMA) dendrogram using two molecular markers divided 54 castor genotypes into three groups. Furthermore, based on morphological data, all 54 castor varieties were grouped into three main clusters. The genetic diversity analysis based on two molecular makers showed that most varieties from China were closely related to each other with three varieties (GUANGDONGwild, ZHEJIANGWild, and HANNANWild) belonging to a wild group separated from most of the cultivated castor samples from China, India, France, and Jordan. These results suggested that the cultivated castor contains a narrow genetic base. Accordingly, we recommend that wild castor genetic resources be introduced for breeding novel castor varieties. Furthermore, the Vietnam, Malaysia, Indonesia, and Nigeria accessions were clustered into the same group. The results of principal coordinate analysis (PCoA) and UPGMA cluster analysis were consistent with each other. The findings of this study are important for future breeding studies of castor.

In recent years, with the use of mobile phone APPs, more and more people like to use tourism APPs when traveling, and the tourism industry also enters a new era of wireless tourism. College students are a huge tourist group. This paper will summarize an APP suitable for students’ tourism through the analysis of tourism APPs and tourist groups. This APP will make travel plans based on the student’s time, including travel time, travel residence, travel strategy, travel expenses, tour groups, etc. It also includes working with schools and local police to keep students safe. There should be such an APP for student travel to make it convenient for students to travel, enrich their university experience, and make student travel safer and more convenient.

Background: There is an unmet need for a reliable method of airway management for patients in the lateral position. This prospective randomized controlled two-center study was designed to evaluate the feasibility of intubation using a flexible fiberoptic bronchoscope in the lateral position during surgery. Methods: Seventy-two patients scheduled for elective nonobstetric surgery in the lateral decubitus position requiring tracheal intubation under general anesthesia at Lishui Central Hospital of Zhejiang Province and Jiaxing First Hospital of Zhejiang Province from April 1, 2015, to September 30, 2015, were enrolled in this study. Patients were randomly assigned to the supine position group (Group S, n = 38) and the lateral position group (Group L, n = 34). Experienced anesthetists performed tracheal intubation with a fiberoptic bronchoscope after general anesthesia. The time required for intubation, intubation success rates, and hemodynamic changes was recorded. Between-group differences were assessed using the Student's t-test, Mann–Whitney U-test, or Chi-square test. Results: The median total time to tracheal intubation was significantly longer in Group S (140.0 [135.8, 150.0] s) compared to Group L (33.0 [24.0, 38.8] s) (P < 0.01). The first-attempt intubation success rate was significantly higher in Group L (97%) compared to Group S (16%). Hemodynamic changes immediately after intubation were more exaggerated in Group S compared to Group L (P = 0.02). Conclusion: Endotracheal intubation with a flexible fiberoptic bronchoscope may be an effective and timesaving technique for patients in the lateral position. Trial Registration: Chinese Clinical Trial Register, ChiCTR-IIR-16007814; http://www.chictr.org.cn/showproj.aspx?proj=13183.