1,478 research outputs found

    Atomic and magnetic structures of (CuCl)LaNb2_2O7_7 and (CuBr)LaNb2_2O7_7: Density functional calculations

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    The atomic and magnetic structures of (CuXX)LaNb2_2O7_7 (XX=Cl and Br) are investigated using the density-functional calculations. Among several dozens of examined structures, an orthorhombic distorted 2×22\times 2 structure, in which the displacement pattern of XX halogens resembles the model conjectured previously based on the empirical information is identified as the most stable one. The displacements of XX halogens, together with those of Cu ions, result in the formation of XX-Cu-XX-Cu-XX zigzag chains in the two materials. The nearest-neighbor interaction within the zigzag chains are determined to be antiferromagnetic (AFM) for (CuCl)LaNb2_2O7_7 but ferromagnetic (FM) for (CuBr)LaNb2_2O7_7. On the other hand, the first two neighboring interactions between the Cu cations from adjacent chains are found to be AFM and FM respectively for both compounds. The magnitudes of all these in-plane exchange couplings in (CuBr)LaNb2_2O7_7 are evaluated to be about three times those in (CuCl)LaNb2_2O7_7. In addition, a sizable AFM inter-plane interaction is found between the Cu ions separated by two NbO6_6 octahedra. The present study strongly suggests the necessity to go beyond the square J1J2J_1-J_2 model in order to correctly account for the magnetic property of (CuX)X)LaNb2_2O7_7.Comment: 24 pages, 7 figure

    Formal Record of Mecopus hopei Rosenschöld, 1838 (Curculionidae: Conoderinae) in Taiwan

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    Abstract: Mecopus hopei Rosenschöld, 1838 is a common species in Taiwan. However, it has been frequently misspelled in Taiwanese records, leading to its omission from regional catalogs. In this study, we formally record M. hopei in Taiwan and provide dorsal habitus photos and barcode sequences to improve species identification

    Computing Thresholds of Linguistic Saliency

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    PACLIC 21 / Seoul National University, Seoul, Korea / November 1-3, 200

    Qubit Mapping Toward Quantum Advantage

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    Qubit Mapping is a pivotal stage in quantum compilation flow. Its goal is to convert logical circuits into physical circuits so that a quantum algorithm can be executed on real-world non-fully connected quantum devices. Qubit Mapping techniques nowadays still lack the key to quantum advantage, scalability. Several studies have proved that at least thousands of logical qubits are required to achieve quantum computational advantage. However, to our best knowledge, there is no previous research with the ability to solve the qubit mapping problem with the necessary number of qubits for quantum advantage in a reasonable time. In this work, we provide the first qubit mapping framework with the scalability to achieve quantum advantage while accomplishing a fairly good performance. The framework also boasts its flexibility for quantum circuits of different characteristics. Experimental results show that the proposed mapping method outperforms the state-of-the-art methods on quantum circuit benchmarks by improving over 5% of the cost complexity in one-tenth of the program running time. Moreover, we demonstrate the scalability of our method by accomplishing mapping of an 11,969-qubit Quantum Fourier Transform within five hours

    Preparation, characterization, and application of titanium nano-tube array in dye-sensitized solar cells

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    The vertically orientated TiO2 nanotube array (TNA) decorated with TiO2 nano-particles was successfully fabricated by electrochemically anodizing titanium (Ti) foils followed by Ti-precursor post-treatment and annealing process. The TNA morphology characterized by SEM and TEM was found to be filled with TiO2 nano-particles interior and exterior of the TiO2 nano-tubes after titanium (IV) n-butoxide (TnB) treatment, whereas TiO2 nano-particles were only found inside of TiO2 nano-tubes upon titanium tetrachloride (TiCl4) treatment. The efficiency in TNA-based DSSCs was improved by both TnB and TiCl4 treatment presumably due to the increase of dye adsorption

    Distributed Adaptive Attitude Synchronization of Multiple Spacecraft

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    This paper addresses the distributed attitude synchronization problem of multiple spacecraft with unknown inertia matrices. Two distributed adaptive controllers are proposed for the cases with and without a virtual leader to which a time-varying reference attitude is assigned. The first controller achieves attitude synchronization for a group of spacecraft with a leaderless communication topology having a directed spanning tree. The second controller guarantees that all spacecraft track the reference attitude if the virtual leader has a directed path to all other spacecraft. Simulation examples are presented to illustrate the effectiveness of the results.Comment: 13 pages, 11 figures. To appear in SCIENCE CHINA Technological Science

    Altered neuronatin expression in the rat dorsal root ganglion after sciatic nerve transection

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    <p>Abstract</p> <p>Background</p> <p>Several molecular changes occur following axotomy, such as gene up-regulation and down-regulation. In our previous study using Affymetrix arrays, it was found that after the axotomy of sciatic nerve, there were many novel genes with significant expression changes. Among them, neuronatin (Nnat) was the one which expression was significantly up-regulated. Nnat was identified as a gene selectively expressed in neonatal brains and markedly reduced in adult brains. The present study investigated whether the expression of Nnat correlates with symptoms of neuropathic pain in adult rats with transected sciatic nerve.</p> <p>Methods</p> <p>Western blotting, immunohistochemistry, and the Randall and Selitto test were used to study the protein content, and subcellular localization of Nnat in correlation with pain-related animal behavior.</p> <p>Results</p> <p>It was found that after nerve injury, the expression of Nnat was increased in total protein extracts. Unmyelinated C-fiber and thinly myelinated A-δ fiber in adult dorsal root ganglions (DRGs) were the principal sub-population of primary afferent neurons with distributed Nnat. The increased expression of Nnat and its subcellular localization were related to mechanical hyperalgesia.</p> <p>Conclusions</p> <p>The results indicated that there was significant correlation between mechanical hyperalgesia in axotomy of sciatic nerve and the increased expression of Nnat in C-fiber and A-δ fiber of adult DRG neurons.</p

    Pulmonary function change in patients with Sauropus androgynus-related obstructive lung disease 15 years later

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    Background/PurposeLittle is understood about the clinical course and prognosis of patients with Sauropus androgynus-related obstructive lung disease. The aim of this study was to investigate their clinical manifestations and pulmonary function change 15 years after the acute episode.MethodsA descriptive, observational study of patients with S androgynus-related obstructive lung disease, diagnosed 15 years ago, was conducted. We evaluated their pulmonary function and the Modified Medical Research Council (MMRC) dyspnea scale. Saint George’s Respiratory Questionnaire (SGRQ) was also performed. Age- and forced expiratory volume in one second (FEV1)-matched chronic obstructive pulmonary disease (COPD) patients were used as a reference group for comparison of clinical manifestations.ResultsTwenty-nine of 49 patients, diagnosed at our hospital 15 years ago, could be contacted. Four patients died and one patient was ventilator-dependent. Sixteen patients were willing to come to our hospital to have pulmonary function and questionnaire evaluation. The FEV1 of these patients declined only 1.6 ± 21.6 mL/year over a 15-year period. Meanwhile, the severity of their dyspnea and their health-related quality of life were better than age- and FEV1-matched COPD patients as shown by the MMRC dyspnea scale (1.4 ± 0.8 vs. 2.0 ± 1.0; p = 0.037) and symptom domain of the SGRQ (32.6 ± 18.4 vs. 43.5 ± 20.3; p = 0.006).ConclusionAfter an acute deterioration, patients with S androgynus-related obstructive lung disease had a stationary pulmonary function over a period of 15 years, and their clinical manifestations were less severe than age- and FEV1-matched COPD patients. A further study with a larger sample size may be needed to confirm these findings
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