62 results on '"Yao, Heng"'
Search Results
2. Phylogenetic analyses of 41 Y-STRs and machine learning-based haplogroup prediction in the Qingdao Han population from Shandong province, Eastern China
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Guang-Yao Fan, De-Zhi Jiang, Yao-Heng Jiang, Wei Song, Ying-Yun He, and Nixon Austin Wuo
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Aging ,Physiology ,Epidemiology ,Public Health, Environmental and Occupational Health ,Genetics - Published
- 2023
3. First-principles study on electronic states of In2Se3/Au heterostructure controlled by strain engineering
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Sha Han, Cai-Juan Xia, Min Li, Xu-Mei Zhao, Guo-Qing Zhang, Lian-Bi Li, Yao-Heng Su, and Qing-Long Fang
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General Chemical Engineering ,General Chemistry - Abstract
The development of low-dimensional multifunctional devices has become increasingly important as the size of field-effect transistors decreases.
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- 2023
4. Interfacial electronic states and self-formed asymmetric Schottky contacts in polar α-In2Se3/Au contacts
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Sha Han, Cai-Juan Xia, Min Li, Xu-Mei Zhao, Guo-Qing Zhang, Lian-Bi Li, Yao-Heng Su, and Qing-Long Fang
- Abstract
In recent years, the two-dimensional (2D) semiconductor α-In2Se3 has great potential for applications in the fields of electronics and optoelectronics due to its spontaneous iron electrolysis properties. Through ab initio electronic structure calculations and quantum transport simulations, the interface properties and transport properties of α-In2Se3/Au contacts with different polarization directions are studied, and a two-dimensional α-In2Se3 asymmetric metal contact design is proposed. When α-In2Se3 is polarized upward, it forms an n-type Schottky contact with Au, while when α-In2Se3 is polarized downward, it forms a p-type Schottky contact with Au. More importantly, significant rectification effect is found in the asymmetric Au/α-In2Se3/Au field-effect transistor. The carrier transports under positive and negative bias voltages are found to be dominated by thermionic excitation and tunneling, respectively. These findings provide guidance for the further design of 2D α-In2Se3-based transistors.
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- 2023
5. study on the role and impact of digital art in helthcare environment and alsofocus on medical illustration
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Yao Heng and Khairul Azhar Mat Daud
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General Nursing ,Education - Abstract
Numerous clinical experts like to make their own clinical illustrations for use in introductions and distributions with the approach of advanced media, it has become simpler to create great quality illustrations in any event, for those with restricted imaginative abilities including the creator. The development of digital art has set out open doors for both the expert as well as the undeveloped artist. Wandering into digital art creation is conceivable utilizing reasonable digital gear with expansion of a couple of extras. This article portrays the writer's experience with making clinical illustrations utilizing computerized media and examines the advantages of the new innovation. A couple of helpful hints are likewise accommodated clinical experts who might be keen on investigating the choice of making their own illustrations utilizing computerized instruments.
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- 2022
6. Plastome-based Phylogenomic analyses provide insights into the germplasm resource diversity ofCibotiumin China
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Ri-Hong Jiang, Si-Qi Liang, Fei Wu, Li-Ming Tang, Bo Qin, Ying-Ying Chen, Yao-Heng Huang, Kai-Xiang Li, and Xian-Chun Zhang
- Abstract
Germplasm resource is the source of herbal medicine production. Cultivation of superior germplasm resources helps to resolve the serious conflict between long-term population persistence and growing market demand by producing materials with high quality consistently.Cibotium barometzis the original plant of cibotii rhizoma (“Gouji”), a traditional Chinese medicine used in the therapy of pain, weakness, and numbness of lower extremity. Long-history use ofCibotiumhas rendered wild populations of this species declined seriously in China. Without sufficient understanding of species and lineage diversity ofCibotium, it is difficult to propose a targeted conservation scheme at present, let alone selecting high-quality germplasm resources. In order to fill such a knowledge gap, this study sampledC. barometzand relative species throughout their distribution in China, performed genome skimming to obtain plastome data, and conducted phylogenomic analyses. We constructed a well-supported plastome phylogeny of ChineseCibotium, which showed that three species with significant genetic difference distributed in China, namelyC. barometz,C. cumingii, andC. sino-burmaense, a cryptic species endemic to NW Yunnan and adjacent region of NE Myanmar. Moreover, our results revealed two differentiated lineages ofC. barometzdistributed in the east and west side of a classic phylogeographic boundary that probably shaped by monsoons and landforms in China. We also evaluated the resolution of nine traditional barcode loci, and designed five new DNA barcodes based on the plastome data which can discriminate all these species and lineages of ChineseCibotiumaccurately. These novel findings integrated genetic basis will guide conservation planners and medicinal plant breeders to build systematic conservation plans and exploit germplasm resources ofCibotiumin China.
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- 2023
7. Interfacial Electronic States and Self-Formed Asymmetric Schottky Contacts in Polar In2se3/Au Contacts
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Qinglong Fang, Sha Han, Caijuan Xia, Min Li, Xumei Zhao, Guoqing Zhang, Lian-Bi Li, and Yao-Heng Su
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- 2023
8. The commensurate and incommensurate Haldane phases for the spin-1 bilinear-biquadratic model
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Yan-Wei Dai, Ai-Min Chen, Xi-Jing Liu, and Yao-Heng Su
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General Physics and Astronomy - Abstract
The commensurate and incommensurate Haldane phases for the spin-1 bilinear-biquadratic model are investigated using the infinite matrix product state algorithm. The bipartite entanglement entropy can detect a transition point between the two phases. In both phases, the entanglement spectrum shows the double degeneracy. We calculate the nonlocal order parameter of the bond-centered inversion in both phases, which rapidly approaches a saturation value -1 as the segment length increases. The nonlocal order parameter of the bond-centered inversion with a saturation value -1 and the nonzero value string order indicate that the Haldane phase is a symmetry-protected topological phase. To distinguish the commensurate and incommensurate Haldane phases, the transversal spin correlation and corresponding momentum distribution of the structure factor are analyzed. As a result, the transversal spin correlations exhibit different decay forms in both phases.
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- 2022
9. Camellia piloflora S. X. Yang. A. Habitat. B. Adaxial 2022, sp. nov
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Zhang, Qiong, Wu, Fang-Yuan, Huang, Yao-Heng, Ma, Jin-Lin, and Yang, Shi-Xiong
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Tracheophyta ,Magnoliopsida ,Theaceae ,Camellia piloflora ,Camellia ,Biodiversity ,Plantae ,Taxonomy ,Ericales - Abstract
Camellia piloflora S.X. Yang, sp. nov. (Figs. 1 & 2). Type:— CHINA. Guangxi: Debao County, in limestone tiankeng, elev. 400 m, 21 January 2022, S . X. Yang 6868 (holotype KUN1541642; isotypes KUN1544968, K). Diagnosis:— Camellia piloflora is most similar to C. debaoensis R.C. Hu & Y.Q. Liufu, but differs by its sepals puberulent abaxially (vs. glabrous), ovary and styles tomentose (vs. glabrous), filaments pubescent (vs. glabrous) and the outer filaments united for 1/2 (vs. 1/4) of their length from the base. Shrubs, 2−5 m tall; young branches yellowish brown or brown, glabrous, rarely subglabrous; terminal buds glabrous, rarely subglabrous. Leaves alternate; petiole 0.6–1.2 cm long, glabrous, rarely subglabrous; blade elliptic to oblong, 7–11 × 3.5–5.5 cm, thinly leathery, purplish red when young, adaxially dark green and glabrous, shiny, abaxially pale green, sparsely pubescent along midvein and scattered dark brown cork-warts, lateral veins 7−9 pairs, apex acuminate to caudate, margin shallowly serrate with the teeth 1.0−2.0 mm apart, base cuneate to broadly cuneate. Flowers subterminal or axillary, solitary or rarely 2−4 in clusters, 5.5–6.0 cm in diam. Pedicel ca. 2.0–5.0 mm long, glabrous. Bracteoles 4–5, yellowish-green, unequal, 1.0–3.0 × 2.0–4.0 mm, obtuse triangle, lunate to semiorbicular, lowermost bracteoles glabrous on both sides, uppermost ones pubescent on both sides, similar to sepals, margin ciliolate. Sepals 5 (–6), yellowish-green, semiorbicular, round-reniform to suborbicular, 6.0−10.0 × 8.0−14.0 mm, pubescent on both surfaces, margin narrow scarious and ciliate. Petals 8–10, in three whorls, pale yellow, orbicular to elliptic, 2.2−4.5 × 2.2−3.5 cm, pubescent on both surfaces, basally connate to each other and to the stamens for 7–10 mm. Stamens numerous, ca. 3.5 cm long, in 4−5 whorls, filament of the outer whorls basally connate into a tube for ca. 1/2 of the length, outside of the tube and base of the free part of filaments pubescent, filaments of the innermost whorl free, pubescent almost all their length. Ovary ovoid, ca. 6 mm in diam, densely pale yellow tomentose, 3 (–4)-loculed; styles single, 2.6 cm long, apically dividing into 3 (–4) arms of ca. 3–4 mm, basally 3/4 pubescent. Capsule oblate, yellowish green, ca. 6.0 cm in diam, pubescent, with 2 seeds per locule; pericarp ca. 1.0–2.0 mm thick when dry, splitting into 3 valves. Seeds dark brown, hemispherical or cuneate, pubescent. Phenology: —Flowering from January to February; fruiting from September to October. Etymology: —The specific epithet is derived from Latin, “ pilus ”, meaning a hair, and “ flos ”, meaning flower, to referring that the new species has hairy flowers, especially on sepals, petals, stamens and pistils. Vernacular name: —‘ ƚṯfiṯș ’ (mao hua jin hua cha) in Chinese pinyin. Distribution, habitat, and conservation status: — Camellia piloflora grows in the evergreen broad-leaved forests of limestone hills at elevation of 400– 650 m. Only three populations with less than 100 individuals have been found in and near its type locality. Due to the great commercial value, the number of this species may continue to shrink. The location of this species is not the natural reserve, thus can be destroyed by human activity. The area of occupancy is less than 10 km 2 (B2a) with three populations, and the area, extent and/or quality of habitat, and number of mature individuals are declined in future. Therefore, the new species is accessed to Critically Endangered (CR, B2ab (iii, v)), according to Guidelines for using the IUCN Red List Categories and Criteria (IUCN Standards and Petitions Committee 2019). Additional specimens examined (paratypes): — CHINA. Guangxi: Debao County, 30 November 2018, limestone tiankeng, elev. ca. 400 m, S .X. Yang & F.Y. Wu 5895–5901 (KUN); 6 March 2019, limestone tiankeng, elev. ca. 400 m, S .X. Yang & F.Y. Wu 5979–5982 (KUN); 8 March 2019, limestone hills, elev. ca. 650 m, S .X. Yang & F.Y. Wu 5983–5985 (KUN); 8 March 2019, limestone tiankeng, elev. ca. 550 m, S .X. Yang & F.Y. Wu 5986 (KUN); 15 September 2020, limestone tiankeng, elev. ca. 400 m, S .X. Yang, F.Y. Wu & P. M. Ye 6395-6397 (KUN); 16 September 2020, limestone tiankeng, elev. ca. 550 m, S .X. Yang, F.Y. Wu & P. M. Ye 6406–6409 (KUN); 21 January 2022, limestone tiankeng, elev. ca. 400 m, S .X. Yang & F.Y. Wu 6869–6871, 6880 (KUN)., Published as part of Zhang, Qiong, Wu, Fang-Yuan, Huang, Yao-Heng, Ma, Jin-Lin & Yang, Shi-Xiong, 2022, Camellia piloflora (Theaceae), a new yellow camellia from Guangxi, South China, pp. 179-184 in Phytotaxa 574 (2) on pages 179-180, DOI: 10.11646/phytotaxa.574.2.7, http://zenodo.org/record/7380906
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- 2022
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10. Camellia piloflora (Theaceae), a new yellow camellia from Guangxi, South China
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QIONG ZHANG, FANG-YUAN WU, YAO-HENG HUANG, JIN-LIN MA, and SHI-XIONG YANG
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Tracheophyta ,Magnoliopsida ,Theaceae ,Plant Science ,Biodiversity ,Plantae ,Ecology, Evolution, Behavior and Systematics ,Taxonomy ,Ericales - Abstract
Zhang, Qiong, Wu, Fang-Yuan, Huang, Yao-Heng, Ma, Jin-Lin, Yang, Shi-Xiong (2022): Camellia piloflora (Theaceae), a new yellow camellia from Guangxi, South China. Phytotaxa 574 (2): 179-184, DOI: 10.11646/phytotaxa.574.2.7, URL: http://dx.doi.org/10.11646/phytotaxa.574.2.7
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- 2022
11. Effect of chemical structure on dispersity of polycarboxylate superplasticiser in cement paste
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Ke Kai, Wang Yingbin, and Yao Heng
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Materials science ,Chemical structure ,Dispersity ,0211 other engineering and technologies ,02 engineering and technology ,Building and Construction ,01 natural sciences ,Cement paste ,010406 physical chemistry ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,021105 building & construction ,Side chain ,General Materials Science ,Acrylic acid - Abstract
This study examines the mechanism of adsorption–dispersion by superplasticisers with varying side chain density in cement paste. Acrylic acid was used to copolymerise with 2-methylprop-2-ene polyethylene glycol, using chain transfer agent to synthesise polycarboxylate ether superplasticisers (PCEs) with comparable main chain lengths and different side chain densities. Gel permeation chromatography, zeta potential, total organic carbon and fluidity tests were used to investigate the adsorption–dispersion of PCE samples in cement pastes with different amounts of tricalcium aluminate (C3A) additive. The results indicate: products with higher side chain densities also have correspondingly shorter main chains, which allows them to form conformations with comparable initial adsorption performance; with C3A added, samples with denser side chains performed better, and their resistance to adsorption became more prominent at higher C3A content.
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- 2020
12. In-vehicle alertness monitoring for older adults
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Yao, Heng, Motamedi, Sanaz, Giang, Wayne C. W., Kondyli, Alexandra, and Jain, Eakta
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H.5.2 ,FOS: Computer and information sciences ,I.5.4 ,Computer Vision and Pattern Recognition (cs.CV) ,Computer Science - Computer Vision and Pattern Recognition ,Computer Science - Human-Computer Interaction ,Human-Computer Interaction (cs.HC) - Abstract
Alertness monitoring in the context of driving improves safety and saves lives. Computer vision based alertness monitoring is an active area of research. However, the algorithms and datasets that exist for alertness monitoring are primarily aimed at younger adults (18-50 years old). We present a system for in-vehicle alertness monitoring for older adults. Through a design study, we ascertained the variables and parameters that are suitable for older adults traveling independently in Level 5 vehicles. We implemented a prototype traveler monitoring system and evaluated the alertness detection algorithm on ten older adults (70 years and older). We report on the system design and implementation at a level of detail that is suitable for the beginning researcher or practitioner. Our study suggests that dataset development is the foremost challenge for developing alertness monitoring systems targeted at older adults. This study is the first of its kind for a hitherto under-studied population and has implications for future work on algorithm development and system design through participatory methods., Comment: 12 pages, 14 figures, 6 tables
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- 2022
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13. Additional file 1 of MiRNA/mRNA network topology in hepatitis virus B-related liver cirrhosis reveals miR-20a-5p/340-5p as hubs initiating fibrosis
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Yao, Heng, Li, Peng, Xin, Jiaojiao, Liang, Xi, Jiang, Jing, Shi, Dongyan, Li, Jiang, Hassan, Hozeifa Mohamed, Chen, Xin, and Li, Jun
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Additional file 1. Supplemental Materials.
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- 2022
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14. Additional file 2 of MiRNA/mRNA network topology in hepatitis virus B-related liver cirrhosis reveals miR-20a-5p/340-5p as hubs initiating fibrosis
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Yao, Heng, Li, Peng, Xin, Jiaojiao, Liang, Xi, Jiang, Jing, Shi, Dongyan, Li, Jiang, Hassan, Hozeifa Mohamed, Chen, Xin, and Li, Jun
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Additional file 2. Supplemental Tables.
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- 2022
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15. The facilities and performance of TianQin laser ranging station
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Caishi Zhang, Tianquan Gao, Yuyan Cao, Zhongwei Fan, Honglin Fu, De-Feng Gu, Xida Han, Yutao Huang, Lin Kang, Ke Li, Ming Li, Rongwang Li, Yu-Qiang Li, Zhulian Li, Zun-Biao Li, Jun-Xiang Lian, Junchi Liu, Qi Liu, Sheng-Qian Liu, Yuan Liu, Jianwei Mei, Xiaoyu Pi, Cheng-Gang Shao, Ji Sun, Yu-Jie Tan, Yuhua Tang, Liang-Cheng Tu, Panpan Wang, Saijin Wang, Peiheng Wu, Qinglin Wu, Liang Xiong, Yao-Heng Xiong, Chao Xue, Yong Yan, Shan-Qing Yang, Hsien-Chi Yeh, Dongsheng Zhai, Haitao Zhang, Hongbo Zhang, Labao Zhang, Lihua Zhang, Hong-Chao Zhao, Guo-Dong Zhou, and Jun Luo
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Physics and Astronomy (miscellaneous) - Abstract
The TianQin Project is aiming at gravitational wave (GW) detection in space. TianQin GW observatory comprises three satellites orbiting on 1 × 105 km Earth orbits to form an equilateral-triangle constellation. In order to minimize the variations in arm lengths and breathing angles, the satellites must be launched and adjusted precisely into an optimized orbit. Therefore, satellite laser ranging must be used to enhance the precision of satellite orbit determination. To develop the capability of satellite laser ranging for TianQin’s orbit, the TianQin Laser Ranging Station has been designed and constructed to perform high-precision laser ranging for TianQin satellites and lunar laser ranging as well. Applying a 1064 nm Nd: YAG laser with 100 Hz repetition frequency, 80 pico-second pulse duration, and 2 × 2 array of superconducting nanowire single-photon detectors, we have obtained the laser echo signals from the five lunar retro-reflector arrays, and the measurement data have been packaged into 234 normal points (NPs), including a few data measured during the full-moon lunar phase. Each NP is calculated from continuous measurement for about ten minutes and the statistical error of the NPs is about 7 mm (1σ).
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- 2022
16. Quantum criticality in spin-1/2 anisotropic XY model with staggered Dzyaloshinskii–Moriya interaction
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Yao Heng Su, D.C. Liu, Zhongyu Wan, Ai Min Chen, and Pengfei Cheng
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Statistics and Probability ,Statistical and Nonlinear Physics - Published
- 2022
17. Additional file 7 of Predicted functional interactome of Caenorhabditis elegans and a web tool for the functional interpretation of differentially expressed genes
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Chen, Peng-Cheng, Ruan, Li, Jin, Jie, Tao, Yu-Tian, Xiao-Bao Ding, Zhang, Hai-Bo, Guo, Wen-Ping, Qiao-Lei Yang, Yao, Heng, and Chen, Xin
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education ,sense organs ,skin and connective tissue diseases ,humanities - Abstract
Additional file 7: Table S6. Annotations produced by DAVID for the transcriptionally changed genes.
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- 2020
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18. Additional file 1 of Predicted functional interactome of Caenorhabditis elegans and a web tool for the functional interpretation of differentially expressed genes
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Chen, Peng-Cheng, Ruan, Li, Jin, Jie, Tao, Yu-Tian, Xiao-Bao Ding, Zhang, Hai-Bo, Guo, Wen-Ping, Qiao-Lei Yang, Yao, Heng, and Chen, Xin
- Abstract
Additional file 1: Table S1. Number of protein-protein interactions and participating unique proteins from three databases.
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- 2020
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19. Additional file 6 of Predicted functional interactome of Caenorhabditis elegans and a web tool for the functional interpretation of differentially expressed genes
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Chen, Peng-Cheng, Ruan, Li, Jin, Jie, Tao, Yu-Tian, Xiao-Bao Ding, Zhang, Hai-Bo, Guo, Wen-Ping, Qiao-Lei Yang, Yao, Heng, and Chen, Xin
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ComputingMethodologies_PATTERNRECOGNITION - Abstract
Additional file 6: Table S5. Annotations produced by the GO enrichment analysis tool for the transcriptionally changed genes.
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- 2020
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20. Additional file 2 of Predicted functional interactome of Caenorhabditis elegans and a web tool for the functional interpretation of differentially expressed genes
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Chen, Peng-Cheng, Ruan, Li, Jin, Jie, Tao, Yu-Tian, Xiao-Bao Ding, Zhang, Hai-Bo, Guo, Wen-Ping, Qiao-Lei Yang, Yao, Heng, and Chen, Xin
- Abstract
Additional file 2: Table S2. Functional association evidence and computing methods.
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- 2020
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21. Additional file 3 of Predicted functional interactome of Caenorhabditis elegans and a web tool for the functional interpretation of differentially expressed genes
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Chen, Peng-Cheng, Ruan, Li, Jin, Jie, Tao, Yu-Tian, Xiao-Bao Ding, Zhang, Hai-Bo, Guo, Wen-Ping, Qiao-Lei Yang, Yao, Heng, and Chen, Xin
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Data_FILES - Abstract
Additional file 3: Table S3. Assessment of feature quality.
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- 2020
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22. Additional file 8 of Predicted functional interactome of Caenorhabditis elegans and a web tool for the functional interpretation of differentially expressed genes
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Chen, Peng-Cheng, Ruan, Li, Jin, Jie, Tao, Yu-Tian, Xiao-Bao Ding, Zhang, Hai-Bo, Guo, Wen-Ping, Qiao-Lei Yang, Yao, Heng, and Chen, Xin
- Abstract
Additional file 8: Table S7. Annotations produced by FIC/GSLA for the transcriptionally changed genes.
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- 2020
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23. Additional file 4 of Predicted functional interactome of Caenorhabditis elegans and a web tool for the functional interpretation of differentially expressed genes
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Chen, Peng-Cheng, Ruan, Li, Jin, Jie, Tao, Yu-Tian, Xiao-Bao Ding, Zhang, Hai-Bo, Guo, Wen-Ping, Qiao-Lei Yang, Yao, Heng, and Chen, Xin
- Abstract
Additional file 4: Figure S1. Receiver operating characteristic (ROC) curves of 36 feature values. Features with areas under the curve (AUC) above 0.6 were selected for use in the SVM model to predict functional interactions between genes.
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- 2020
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24. Effect of the anchoring groups on the switching behaviour of the dihydroazulene/vinylheptafulvene molecular junction with zigzag-edged graphene nanoribbons electrodes
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Cai-Juan Xia, Ai-Yun Yang, Jun Wang, Bo-Qun Zhang, Yao Heng Su, and Zhe-Yan Tu
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Molecular switch ,Materials science ,Oscillation ,Biophysics ,Anchoring ,Nanotechnology ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,0104 chemical sciences ,Zigzag ,Chemical physics ,Electrode ,Molecule ,Density functional theory ,Physical and Theoretical Chemistry ,0210 nano-technology ,Molecular Biology ,Graphene nanoribbons - Abstract
The switching behaviour of dihydroazulene/vinylheptafulvene molecule with different anchoring groups sandwiched between two zigzag-edged graphene nanoribbons (ZGNRs) electrodes is investigated by applying nonequilibrium Green's function formalism combined with first-principles density functional theory. The calculated results show that the anchoring groups play a significant role in determining the electronic transport properties and switching behaviour of the molecular junctions. A higher current switching ratio without any oscillation can be obtained for the molecular junctions with carbon atom anchoring group, which suggests that this system has a broader application in future logic and memory devices.
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- 2017
25. Making Virtual Reality Social
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Yao Heng, Fatemeh Tavassoli, Andrew Cordar, Jeffrey Wood, and Benjamin Lok
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Human–computer interaction ,Computer science ,Virtual reality - Published
- 2019
26. Switching characteristics of anthraquinone molecular devices based on graphene electrodes
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Zhang Ting-Ting, Cui Yan, Xia Cai-Juan, Tang Xiao-Jie, Hu Zhen-Yang, Zhang Bo-Qun, Su Yao-Heng, and Liu Yang
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chemistry.chemical_compound ,Materials science ,Graphene electrode ,chemistry ,General Physics and Astronomy ,Nanotechnology ,Anthraquinone - Abstract
With the development of microelectronics and the miniaturization of electronic devices, the use of molecular materials to construct various components in electronic circuits has become a most likely development trend. Compared with silicon-based semiconductor components, molecular electronic device has the advantages of small size, high integration, low energy consumption and fast response. In recent years, more and more molecules have been used to design molecular devices such as molecular diodes, molecular switches, molecular field effect transistors and molecular memories. In this paper, sandwich structure devices based on graphene nanoribbon electrodes are constructed. The first-principles calculation method combining density functional theory and non-equilibrium Green’s function is adopted to design the molecular devices with functional characteristics. The effects of redox reactions on the electrical transport properties of molecular devices are systematically discussed. The main research contents of this paper are as follows. The switching characteristics of an anthraquinone molecular device based on graphene electrode are studied. The zigzag-edge nanoribbons and armchair-edge graphene nanoribbons are selected as electrodes. Considering the two isomers of anthraquinone (HQ) and anthraquinone (AQ) molecules in the redox reaction, the double electrode molecular junction is constructed. The effects of redox reaction and electrode structure on the switching characteristics of anthraquinone molecular devices are discussed. It is found that the current in the HQ configuration is significantly greater than that in the AQ configuration, regardless of the zigzag-edge graphene electrode or the armchair-edge graphene electrode. That is, under the redox reaction, the anthraquinone molecules show significant switching characteristics. The switching ratio of zigzag-edge graphene electrode is selected to reach a maximum of 3125, and that of armchair-edge graphene electrode is selected to maximum of 1538. In addition, when the armchair-edge graphene is used as an electrode in the HQ configuration, the negative differential resistance is obviously between 0.7 and 0.9 V.
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- 2021
27. Electronic transport properties of a single chiroptical molecular switch with graphene nanoribbons electrodes
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Xiang-an Yan, Zhe-Yan Tu, Bo-Qun Zhang, Yao-Heng Su, and Cai-Juan Xia
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Molecular switch ,Materials science ,Graphene ,Nanotechnology ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,0104 chemical sciences ,Electronic, Optical and Magnetic Materials ,law.invention ,Zigzag ,law ,Chemical physics ,Electrode ,Molecule ,Density functional theory ,Electrical and Electronic Engineering ,0210 nano-technology ,Chirality (chemistry) ,Graphene nanoribbons - Abstract
Based on the nonequilibrium Green's function method and density functional theory calculations, we investigate the electronic transport properties of a single chiroptical molecular switch with two zigzag graphene nanoribbon electrodes. The molecule undergoing the switch can exhibit different chirality namely cis -isomer and trans -isomer by ultraviolet or visible irradiation. Theoretical results clearly reveal that these two isomers exhibit very different current – voltage characteristics, which can realize the switching behaviors when the molecule converts between cis -isomer and trans -isomer. Furthermore, the negative differential resistance behaviors also can be observed in these two isomers, suggesting potential applications of this type of junctions in future design of functional molecular devices.
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- 2016
28. Physical observable for one-dimensional the spin-1 Blume–Capel model
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Chunhuan Xiang, Honglei Wang, Yao Heng Su, and Ai Min Chen
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Statistics and Probability ,Quantum phase transition ,Physics ,Phase transition ,Schmidt decomposition ,Observable ,Quantum entanglement ,Condensed Matter Physics ,01 natural sciences ,010305 fluids & plasmas ,0103 physical sciences ,Statistical physics ,010306 general physics ,Critical exponent ,Scaling ,Matrix product state - Abstract
We carry out an extensive study, within the infinite matrix product state algorithm, one-dimensional spin-1 Blume–Capel model on the spin-chain and subject to a changeable external magnetic field. The phase transition points are obtained by investigating the behavior of physical observable and as well as exacting the critical exponent from the scaling relationship. The final results are achieved for the physical observable-quantum entanglement entropy, local order parameter and its scaling: the scaling relationship between quantum entanglement entropy and truncation dimension, the scaling of Schmidt decomposition coefficient λ m a x and truncation dimension, the critical exponent of local order parameter near the phase transition point is extracted with the scaling behavior for the model with exchange coupling γ = 0 . 6 . These techniques are an easy way to exact the critical exponent for quantum phase transitions.
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- 2020
29. Quantum phase transition and topological order scaling in spin-1 bond-alternating Heisenberg model with Dzyaloshinskii-Moriya interaction
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Dong-Chang Liu, Chun-Huan Xiang, Hong-Lei Wang, Jia Duan, Yao-Heng Su, and Ai-Min Chen
- Subjects
Physics ,Quantum phase transition ,Condensed matter physics ,Heisenberg model ,General Physics and Astronomy ,Topological order ,Scaling ,Spin-½ - Abstract
Quantum phase transitions are driven by quantum fluctuations due to the uncertainty principle in many-body physics. In quantum phase transitions, the ground-state changes dramatically. The quantum entanglement, specific heat, magnetization and other physical quantities diverge according to certain functions, and show specific scaling behaviors. In addition, there is a topological quantum phase transition beyond the conventional Landau-Ginzburg-Wilson paradigm, which is relevant to emergent phenomena in strongly correlated electron systems, with topological nonlocal order parameters as a salient feature. Thus, topological order is a new paradigm in the study of topological quantum phase transitions.To investigate competition mechanism of the different quantum spin interactions, in this paper, the one-dimensional spin-1 bond-alternating Heisenberg model with Dzyaloshinskii-Moriya (DM) interaction is considered. The DM interaction drives the quantum fluctuations resulting in a phase transition. By using the one-dimensional infinite matrix product state algorithm in tensor network representation, the quantum entanglement entropy and order parameters are calculated from the ground-state function. The numerical result shows that with the change of bond alternating strength, there is a quantum phase transition from the topological ordered Haldane phase to the local ordered dimer phase. Based on the von Neumann entropy and order parameter, the phase diagram of this model is obtained. There is a critical line that separates the Haldane and the dimer phase. The DM interaction inhibits the dimerization of the quantum spin system and finally breaks the fully dimerization. Due to the fact that the structurally symmetry of system is broken, the local dimer order exists in the whole parameter range when the bond-alternative strength parameter changes. The first derivative of the local dimer order behaves as a peak corresponding to the critical point. Furthermore, from the numerical scaling of the first derivative of dimer order and the non-local string order near the phase transition point, the characteristic critical exponents α and β are obtained, respectively. It shows that the characteristic critical exponent α decreases, and β increases gradually with the interaction strength of DM increasing. The resulting state i.e. the anti-symmetric anisotropic DM interaction produced by spin-orbit coupling, affects the critical properties of the system in the phase transition. This reveals that the competition mechanism of the quantum spin interaction, also provides some guidance for the future study of the critical behavior in topological quantum phase transition with the DM interaction.
- Published
- 2020
30. Quantum phase transition in the one-dimensional quantum Heisenberg XYZ model with Dzyaloshinskii–Moriya interaction
- Author
-
Honglei Wang, Ai Min Chen, Chunhuan Xiang, and Yao Heng Su
- Subjects
Physics ,Quantum phase transition ,Quantum discord ,Quantum limit ,Time-evolving block decimation ,Quantum entanglement ,Condensed Matter Physics ,01 natural sciences ,010305 fluids & plasmas ,Electronic, Optical and Magnetic Materials ,Quantum mechanics ,0103 physical sciences ,Quantum system ,Quantum algorithm ,010306 general physics ,Matrix product state - Abstract
We investigated the quantum phase transition occurred in one-dimensional quantum Heisenberg XYZ model with Dzyaloshinskii–Moriya interaction via the infinite matrix product state representation with the infinite time evolving block decimation method. Entanglement entropy and local order parameter in and near the transition point are given. Scaling relation plays crucial roles on identifying a quantum system with a physically different phase. The scaling relation of the entanglement entropy, local order parameter and finite correlation length with the truncation dimension are also obtained. All the interesting results give a theoretical justification for the high accuracy of infinite time evolved block decimation algorithm which works in the thermodynamical limit.
- Published
- 2017
31. Investigate into Variation Cashmere Fibers with Raman Spectra
- Author
-
Guo Qing Zhang, Xiang An Yan, Han Chen Liu, Li Wen Zhang, and Yao Heng Su
- Subjects
Materials science ,Aqueous solution ,Organic solvent ,General Engineering ,Analytical chemistry ,Fluorescence ,symbols.namesake ,chemistry.chemical_compound ,chemistry ,Impurity ,symbols ,Ultrasonic sensor ,Fiber ,Diethyl ether ,Raman spectroscopy - Abstract
There is much fluorescence for impurities on the variation cashmere fiber surface; the characteristic of the Raman spectrum is not obvious. Based on the orthogonal principle, variation cashmere fiber is purified by soaking in different component water/organic solvents, and cleaning with ultrasonic wave. Through measuring and analyzing the Raman spectrum, we confirm the optimal organic solvent system, soaking time and temperature for the cleanse technology of variation cashmere. The result shows that, the variation cashmere fiber is soaked in diethyl ether/aqueous organic solvent in the optimal condition, the Raman spectrum appears good peak-area ratio, and we get cleanest variation cashmere fiber.
- Published
- 2014
32. Global geometric entanglement and quantum phase transition in three-leg spin-3/2 Heisenberg tubes
- Author
-
Cai-Juan Xia, Sam Young Cho, Yao Heng Su, and Ai Min Chen
- Subjects
Quantum phase transition ,Physics ,Quantum Physics ,Quantum phases ,Quantum entanglement ,Condensed Matter Physics ,Squashed entanglement ,01 natural sciences ,Multipartite entanglement ,010305 fluids & plasmas ,Electronic, Optical and Magnetic Materials ,Quantum mechanics ,0103 physical sciences ,Quantum spin liquid ,W state ,010306 general physics ,Wave function - Abstract
Based on the tensor network representations, we have developed an efficient scheme to calculate the global geometric entanglement as a multipartite entanglement measure for the three-leg spin tubes. From the geometric entanglement, the phase diagram of a spin-3 / 2 isosceles triangle spin tube has been investigated varying the base interaction α. Two Berezinsky-Kosterlitz-Thouless phase transitions are estimated to be α c1 ≃ 0.68 and α c2 ≃ 3.85, respectively. Then, even though the spin tube is in gapless spin liquid phases for α < α c1 and α > α c2, the geometrical structure difference between the groundstate wavefunctions for the two regions is found to reflect the global geometric entanglement that contains bipartite and multipartite contributions. Further, the phase transition points from the von Neumann entropies and fidelity are consistent with that from the geometric entanglement. As a result, the global geometric entanglement can be used to explore a geometrical nature of quantum phases as well as an indicator for quantum phase transitions in many-body lattice systems.
- Published
- 2016
33. Palladium immobilized in the nanocages of SBA-16: An efficient and recyclable catalyst for Suzuki coupling reaction
- Author
-
Jian Sun, Honglei Yang, Jiantai Ma, Zongyan Ma, Fengwei Zhang, Haibo Wang, and Yao-heng Zhang
- Subjects
Materials science ,Catalyst support ,Inorganic chemistry ,chemistry.chemical_element ,General Chemistry ,Condensed Matter Physics ,Coupling reaction ,Catalysis ,Nanocages ,chemistry ,Suzuki reaction ,Chemical engineering ,Mechanics of Materials ,Heck reaction ,General Materials Science ,Mesoporous material ,Palladium - Abstract
A novel solid catalyst for coupling reaction has been successfully prepared by immobilizing palladium in the nanocages of the ethylenediamine-functionalized mesoporous material SBA-16. The structure and composition of the solid catalyst were characterized by N2 adsorption–desorption, XRD, TEM, FT-IR and TGA. These results revealed that Pd(II) was successfully embedded inside the nanocages of SBA-16. This catalyst afforded high activity (over 91% conversion) for the Suzuki coupling of various aryl bromides and phenyiboronic acids in ethanol solvent at 60 °C even at the loading of 0.5 mol% Pd. Moreover, the SBA-16-2 N-Pd(II) catalyst could be separated easily from reaction mixture and reused for ten times without obvious loss of catalytic activity, showing the superiority over the homogeneous catalysts in industrial applications.
- Published
- 2013
34. A new method for calculating the efficiency of transformer radiator
- Author
-
Zhao Shihua, Peng Ping, Qin Jia-yuan, Hu Hai-ning, Liu Yun, Xie Yao-heng, and He Shu-di
- Subjects
Load capacity ,Engineering ,business.industry ,law ,Electrical engineering ,Energy efficient transformer ,business ,Distribution transformer ,Transformer ,Automotive engineering ,Oil temperature ,law.invention - Abstract
At present, the factory often use transformer factory calculation method to calculate the top oil temperature rise, according to the calculated results, the allocation of a certain heat dissipating capacity of the radiator, so as to ensure to meet the standard requirements of the top oil temperature rise. Transformer after the operation, due to environmental factors, the radiator efficiency will be decreased to a certain extent, when the load is high, easy to appear the top oil temperature rise high phenomenon, thus affecting the normal operation of transformer. Therefore, based on the top oil temperature rise factory calculation method, proposes a calculating method of transformer radiator efficiency, it provided the basis for the evaluation of the load capacity of the transformer and the formulation of radiator repair plan.
- Published
- 2016
35. The scaling behavior for one-dimensional quantum two-spin and three-spin model
- Author
-
Honglei Wang, Chunhuan Xiang, Yao Heng Su, and Ai Min Chen
- Subjects
Physics ,Phase transition ,Time-evolving block decimation ,Hilbert space ,General Physics and Astronomy ,Observable ,01 natural sciences ,010305 fluids & plasmas ,symbols.namesake ,Quantum mechanics ,0103 physical sciences ,Spin model ,symbols ,Statistical physics ,010306 general physics ,Spin (physics) ,Scaling ,Matrix product state - Abstract
The scaling behavior of physical observable in the phase transition point for one-dimensional quantum two-spin and three-spin model is investigated by employing the infinite matrix product state representation with the infinite time evolving block decimation method. The analytical results, which are checked numerically finding excellent agreement for the model with central charge c = 4/5 , demonstrate that the scaling behavior with finite truncation dimension $ \chi$ in local Hilbert space can be employed to characterize the one-dimensional quantum spin model. Meanwhile, the infinite time evolving block decimation algorithm by the infinite matrix product state representation can be a quite accurate method to obtain the critical properties at continuous phase transition point.
- Published
- 2016
36. Pd immobilized on thiol-modified magnetic nanoparticles: A complete magnetically recoverable and highly active catalyst for hydrogenation reactions
- Author
-
Haibo Wang, Yu-Bin Zhang, Honglei Yang, Yao-heng Zhang, Fengwei Zhang, Jiantai Ma, Rong Li, and Jianrui Niu
- Subjects
Thermogravimetric analysis ,Materials science ,Inorganic chemistry ,chemistry.chemical_element ,General Chemistry ,Condensed Matter Physics ,Nanomaterials ,Catalysis ,X-ray photoelectron spectroscopy ,chemistry ,Yield (chemistry) ,Magnetic nanoparticles ,General Materials Science ,Inductively coupled plasma ,Palladium - Abstract
A palladium-based catalyst supported on thiol-modified superparamagnetic nanoparticles was successfully prepared by co-precipitation method. These magnetic nanomaterials were characterized by elemental analysis (EA), inductively coupled plasma (ICP), X-ray powder diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), fourier transform-infrared (FT-IR), thermogravimetric analysis (TGA) and vibrating sample magnetometry (VSM). The conversions of various aromatic nitro and unsaturated compounds can receive a really high yield with the existence of magnetic nanomaterials. The turn-over frequency (TOF) can be 66.46 h−1 in ethanol under a H2 atmosphere at room temperature. In this paper, the conversions of aromatic nitro bearing a variety of substituents were 93.56–100%, moreover, the catalyst afforded over 90% yield in the reducing unsaturated compounds. Another advantage is that the magnetite nanoparticles modified by thiol group can be separated just through the external magnetic force and can be reused atleast ten times without any significant loss in activity.
- Published
- 2012
37. Fano-Andreev transport and circulating currents in mesoscopic interferometers
- Author
-
Yao Heng Su and Sam Young Cho
- Subjects
Superconductivity ,Physics ,Mesoscopic physics ,Amplitude ,Condensed matter physics ,Condensed Matter::Superconductivity ,Quantum correlation ,Quasiparticle ,General Physics and Astronomy ,Condensed Matter::Mesoscopic Systems and Quantum Hall Effect ,Antiresonance ,Excitation ,Andreev reflection - Abstract
Quantum correlation and interference effects are investigated in mesoscopic interferometers connected to a normal metal and a superconductor. For quasiparticle excitation energies smaller than superconducting gap, a Fano-Andreev antiresonance for zero excitation energy is shown to be split into two zero-transmissions located at energies lower and higher than the Fano-Andreev antiresonance energy. For an excitation energy bigger than the gap, the higher energy antiresonance disappears for electron-like quasiparticle transport. In the presence of a superconductor interface potential Z, we find that the transport and the circulating currents normalized by their amplitudes for a clean interface have the same I(Z)-Z curve. We discuss a transition among the three types of normalized currents, which shows a characteristic transition diagram in association with the excitation energy. Also, as a demonstration of the existence of Andreev holes, we show that only the Andreev hole current can circulate along the interferometer loop.
- Published
- 2012
38. iTRAQ-based quantitative proteomic analysis reveals proteomic changes in leaves of cultivated tobacco (Nicotiana tabacum) in response to drought stress
- Author
-
Dahai Yang, Bai Ge, He Xie, Xiao Bingguang, Zhang Yihan, and Yao Heng
- Subjects
0106 biological sciences ,0301 basic medicine ,Proteomics ,Proteome ,Nicotiana tabacum ,Acclimatization ,Drought tolerance ,Biophysics ,Photosynthesis ,01 natural sciences ,Biochemistry ,Peptide Mapping ,Redox ,03 medical and health sciences ,chemistry.chemical_compound ,Gene Expression Regulation, Plant ,Tandem Mass Spectrometry ,Heat shock protein ,Botany ,Tobacco ,Heat shock ,Abscisic acid ,Molecular Biology ,Heat-Shock Proteins ,Plant Proteins ,Drought ,biology ,fungi ,food and beverages ,Cell Biology ,biology.organism_classification ,Droughts ,Plant Leaves ,030104 developmental biology ,iTRAQ ,chemistry ,Isotope Labeling ,Heat-Shock Response ,010606 plant biology & botany - Abstract
Drought is one of the most severe forms of abiotic stresses that threaten the survival of plants, including crops. In turn, plants dramatically change their physiology to increase drought tolerance, including reconfiguration of proteomes. Here, we studied drought-induced proteomic changes in leaves of cultivated tobacco (Nicotiana tabacum), a solanaceous plant, using the isobaric tags for relative and absolute quantitation (iTRAQ)-based protein labeling technology. Of identified 5570 proteins totally, drought treatment increased and decreased abundance of 260 and 206 proteins, respectively, compared with control condition. Most of these differentially regulated proteins are involved in photosynthesis, metabolism, and stress and defense. Although abscisic acid (ABA) levels greatly increased in drought-treated tobacco leaves, abundance of detected ABA biosynthetic enzymes showed no obvious changes. In contrast, heat shock proteins (HSPs), thioredoxins, ascorbate-, glutathione-, and hydrogen peroxide (H2O2)-related proteins were up- or down-regulated in drought-treated tobacco leaves, suggesting that chaperones and redox signaling are important for tobacco tolerance to drought, and it is likely that redox-induced posttranslational modifications play an important role in modulating protein activity. This study not only provides a comprehensive dataset on overall protein changes in drought-treated tobacco leaves, but also shed light on the mechanism by which solanaceous plants adapt to drought stress.
- Published
- 2015
39. Dimerized phase and entanglement in the one-dimensional spin-1 bilinear biquadratic model
- Author
-
Honglei Wang, Yao Heng Su, and Ai Min Chen
- Subjects
Condensed Matter::Quantum Gases ,Physics ,Phase transition ,Degenerate energy levels ,Time-evolving block decimation ,Von Neumann entropy ,Quantum entanglement ,Condensed Matter Physics ,Squashed entanglement ,Electronic, Optical and Magnetic Materials ,Quantum mechanics ,Condensed Matter::Strongly Correlated Electrons ,Wave function ,Matrix product state - Abstract
Dimerized phase and quantum entanglement are investigated in the one-dimensional spin-1 bilinear biquadratic model. Employing the infinite matrix product state representation, groundstate wavefunctions are numerically obtained by using the infinite time evolving block decimation method in the infinite lattice system. From a bipartite entanglement measure of the groundstates, i.e., von Neumann entropy, the phase transition points can be clearly extracted. Moreover, the even-bond and odd-bond von Neumann entropies show two different values in the spontaneous dimerized phase. It implies that the quantum entanglement can distinguish the two degenerate groundstates. Then, we define a dimer entropy in the spontaneous dimerized phase. Comparing to the dimer order parameter, the dimer entropy can play a role of a local order parameter to characterize the spontaneous dimerized phase.
- Published
- 2015
40. Is the Fano Antiresonance a Necessary Requirement for Circulating Currents in Mesoscopic Interferometers?
- Author
-
Yao Heng Su, Sam Young Cho, Ai Min Chen, and Taeseung Choi
- Subjects
Physics ,Interferometry ,Mesoscopic physics ,Condensed matter physics ,Astronomical interferometer ,General Physics and Astronomy ,Rectangular potential barrier ,Fano plane ,Condensed Matter::Mesoscopic Systems and Quantum Hall Effect ,Antiresonance ,Critical value ,Quantum tunnelling - Abstract
Coherent quantum tunneling effects on quantum interference are investigated in electron transport through a mesoscopic interferometer. An evanescent wave tunneling through a potential barrier in one arm can interfere with a propagating wave passing through the other arm of the interferometer. It is shown that, even for the same arm lengths, such a quantum interference can induce a circulating current, where Fano antiresonances do not occur in electron transmission. It is found that there exists a critical value of asymmetric arm lengths that gives rise to a Fano antiresonance in electron transmission for quantum interference between evanescent and propagating waves. We discuss the effects of Fano antiresonances originating from asymmetric arm lengths on circulating currents.
- Published
- 2010
41. The switching behaviors induced by torsion angle in a diblock co-oligomer molecule with tailoring graphene nanoribbon electrodes
- Author
-
Zhe-Yan Tu, Yao-Heng Su, Bo-Qun Zhang, Jun Wang, Cai-Juan Xia, and Ai-Yun Yang
- Subjects
Molecular switch ,Materials science ,Graphene ,Statistical and Nonlinear Physics ,Nanotechnology ,02 engineering and technology ,Dihedral angle ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,Oligomer ,0104 chemical sciences ,law.invention ,chemistry.chemical_compound ,chemistry ,law ,Chemical physics ,Electrode ,Molecule ,Density functional theory ,0210 nano-technology ,Graphene nanoribbons - Abstract
By applying first-principles method based on density functional theory combined with nonequilibrium Green’s function, we investigate the effect of torsion angle on the electronic transport properties in dipyrimidinyl–diphenyl co-oligomer molecular device with tailoring graphene nanoribbon electrodes. The results show that the torsion angle plays an important role on the electronic transport properties of the molecular device. When the torsion angle rotates from 0[Formula: see text] to 90[Formula: see text], the molecular devices exhibit very different current–voltage characteristics which can realize the on and off states of the molecular switch.
- Published
- 2018
42. Rectifying performances of oligo phenylene ethynylene molecular devices based on graphene electrodes
- Author
-
Cui Yan, Yang Ai-Yun, Xia Cai-Juan, Su Yao-Heng, Liu Yang, Chen Ai-Min, Zhang Bo-Qun, and Zhang Ting-Ting
- Subjects
Materials science ,business.industry ,General Physics and Astronomy ,Molecular electronics ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Acceptor ,0104 chemical sciences ,Rectification ,Electrode ,Optoelectronics ,Molecule ,Density functional theory ,0210 nano-technology ,business ,Graphene nanoribbons ,Voltage - Abstract
With the experimental advances in microscale fabrication technology, the designing of functional devices by using single molecules has become one of the most promising methods for the next generation of electronic devices. Molecular rectifier, as a basic component almost for any electronic device, has become a research hotspot in molecular electronics. Recently, one-dimensional graphene nanoribbons (GNRs) which cut off from the novel two-dimensional material-graphene were used as the electrodes for several molecular devices due to their unique electronic structures and transport characteristics. The GNRs have less serious contact problems than metallic electrode materials like gold. In this paper, we investigate the rectifying performances of oligo phenylene ethynylene molecular devices based on graphene electrodes by using the density-functional theory and the non-equilibrium Green's function method. The effect of functional group on the rectifying performances of molecular device is discussed. The results show that the functional group plays a significant role in determining the rectifying performances of oligo phenylene ethynylene molecular device. The rectifying ratio can be effectively tuned by the functional group: adding the donor group (NH2) can lead to the positive rectifying phenomenon, adding the acceptor group (NO2) can trigger the negative rectifying phenomenon, and simultaneously adding NH2 and NO2 groups can bring about an alternate phenomenon between positive and reverse rectifying . The physical mechanism of the rectifying behavior is explained based on the transmission spectra and molecular projected self-consistent Hamiltonian. The transmission spectra of four models (M1-M4) bias voltages in range from-1.0 V to 1.0 V are given. The main transmission peak of M1 for positive bias is similar to that for negative bias, resulting in a weak rectification ratio. However, for M2 and M3, the main transmission peaks for positive and negative bias are significantly different from each other, which shows obviously a rectifying behavior. For M4, the main transmission peak is higher for the bias of (0.44-0.83 V) and also for the bias (0.95-1.00 V), showing an alternate phenomenon between positive and reverse rectifying. The maximum rectification ratio reaches 2.71 by adding an acceptor group (NO2), which suggests that this system has attractive potential applications in future molecular circuit.
- Published
- 2018
43. Electronic Transport Properties of Diblock Co-Oligomer Molecule Devices Sandwiched between Nitrogen Doping Armchair Graphene Nanoribbon Electrodes *
- Author
-
Zhe-Yan Tu, Ai-Yun Yang, Cai-Juan Xia, Meng Ye, Bo-Qun Zhang, Yue Ma, and Yao-Heng Su
- Subjects
Materials science ,Graphene ,Nitrogen doping ,General Physics and Astronomy ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Oligomer ,law.invention ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,law ,0103 physical sciences ,Electrode ,Molecule ,010306 general physics ,0210 nano-technology - Published
- 2017
44. UnISIS: Laser Guide Star and Natural Guide Star Adaptive Optics System
- Author
-
Abhijit Chakraborty, Laird A. Thompson, Robert W. Leach, Robert A. Gruendl, Richard M. Castle, Yao Heng Xiong, and Scott W. Teare
- Subjects
Physics ,business.industry ,Strehl ratio ,Astronomy and Astrophysics ,Wavefront sensor ,Deformable mirror ,law.invention ,Primary mirror ,Telescope ,Laser guide star ,Optics ,Space and Planetary Science ,law ,Guide star ,business ,Adaptive optics - Abstract
UnISIS (University of Illinois Seeing Improvement System) is a versatile adaptive optics system mounted on a large optics bench at the coude focus of the Mount Wilson 2.5-m telescope. It was designed to have both laser guide star (LGS) and natural guide star (NGS) adaptive optics capabilities. The LGS side of the system relies on a pulsed UV laser with raw power of 30 W capable of creating an artificial laser star via Rayleigh scattering 18 km above the telescope. The LGS system can work at temporal response rates as high as 333 Hz-limited by the UV laser pulse rate-and the NGS system can work at rates up to 1.4 kHz. Each side of the system has its own highspeed wavefront sensor that runs separately, but in the LGS mode the NGS wavefront sensor is converted into a natural star tip-tilt sensor. The deformable mirror is conjugate to the telescope's primary mirror and has one of the most densely packed sets of actuators of any adaptive optics system currently in operation. This paper provides details of the UnISIS design and describes key updates we have made to the system. We show NGS AO-corrected images from the sky from the 900 nm z-band through the 2.12 mu m K(s) band. The highest NGS Strehl achieved to date is 0.67 at K(s) band.
- Published
- 2009
45. Quantum ground-state entanglement for spin-1/2 alternating Heisenberg model in one spatial dimension
- Author
-
Yao Heng Su, Chunhuan Xiang, and Honglei Wang
- Subjects
Quantum phase transition ,Physics ,Quantum discord ,Quantum mechanics ,General Physics and Astronomy ,Von Neumann entropy ,Quantum entanglement ,Squashed entanglement ,Amplitude damping channel ,Critical exponent ,Matrix product state - Abstract
Quantum entanglement for a one-dimensional quantum antiferromagnetic-ferromagnetic spin-1/2 alternating Heisenberg chain is investigated by employing the infinite matrix product state representation. The entanglement entropies for the model are shown and the peaks of the entropies tell us the quantum phase transitions happen when the control parameter crosses its critical value. Besides, spontaneous magnetization is given and the critical exponent is extracted from the data. Finally, a finite-entanglement scaling of the von Neumann entropy and finite-entanglement scaling exponent are given with different truncation dimension, from which the type of the transition and its conformal anomaly parameter c are obtained at the critical point.
- Published
- 2015
46. The entanglement entropy for quantum system in one spatial dimension
- Author
-
Honglei Wang, Longcong Chen, Bo Liang, and Yao Heng Su
- Subjects
Physics ,Quantum discord ,Quantum mechanics ,Quantum entanglement ,Condensed Matter Physics ,Squashed entanglement ,Amplitude damping channel ,Topological entropy in physics ,Multipartite entanglement ,Joint quantum entropy ,Quantum relative entropy ,Electronic, Optical and Magnetic Materials - Abstract
Ground-state entanglement entropies were investigated for the one-dimension quantum two- and three-spin interaction models, the four-state Potts model, and the XXZ model with uniaxial single-ion-type anisotropy, which were obtained on an infinite-size lattice in one spatial dimension. Thus we show that the entanglement, a key concept of quantum information science, is quantified by the ground-state entanglement entropy. The relationships between ground-state entanglement entropy and quantum phase transition was analyzed. These results were obtained using the infinite matrix product state algorithm which works in the thermodynamical limit.
- Published
- 2015
47. Research of regularity of throwing movement for solid particle on the Shaker’s screen
- Author
-
Yao Heng-shen, Zhang Ming-hong, and Du Jian
- Subjects
Inertial frame of reference ,Partial differential equation ,Heaviside step function ,Differential equation ,Plane (geometry) ,Applied Mathematics ,Mechanical Engineering ,Mathematical analysis ,Displacement (vector) ,symbols.namesake ,Mechanics of Materials ,Control theory ,symbols ,Shaker ,Throwing ,Mathematics - Abstract
by means of Delta-function & unit step function to express the force of solid particle on plane inertial shaker’s screen, an mathematical model of the differential equation type was set up and solved. According to analysis of the solution, the relation is given between the throw period & displacement with the parameters of shaker design & solid particle. The method of numerical value calculation & analysis for the relation is given too.
- Published
- 2002
48. Switching behaviors of butadienimine molecular devices sandwiched between graphene nanoribbons electrodes
- Author
-
Meng Ye, Yao-Heng Su, Bo-Qun Zhang, Zhe-Yan Tu, and Cai-Juan Xia
- Subjects
Materials science ,Physics and Astronomy (miscellaneous) ,business.industry ,General Engineering ,General Physics and Astronomy ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Electrode ,Optoelectronics ,0210 nano-technology ,business ,Graphene nanoribbons - Published
- 2017
49. Quantum entanglement and critical exponents in one-dimensional spin-1 bond-alternating XXZ chains
- Author
-
Wang Hong-Lei, Chen Ai-Min, Xiang Chun-Huan, and Su Yao-Heng
- Subjects
Physics ,Condensed matter physics ,General Physics and Astronomy ,Quantum entanglement ,Critical exponent ,Spin-½ - Abstract
The characterization of the quantum phase transition in a lowdimensional system has attracted a considerable amount of attention in quantum manybody systems. As one of the fundamental models in quantum magnetism, spin-1 models have richer phase diagrams and show more complex physical phenomena. In the spin-1 antiferromagnetic XXZ model, the Haldane phase and the Nel phase are the gapped topologic phases which cannot be characterized by the local order parameters. To characterize the nature in such phases, one has to calculate the non-local long range order parameters. Normally, the non-local order parameter in the topological phase is obtained from the extrapolation of finite-sized system in numerical study. However, it is difficult to extract the critical exponents with such an extrapolated non-local order parameter due to the numerical accuracy. In a recently developed tensor network representation, i.e., the infinite matrix product state (iMPS) algorithm, it was shown that the non-local order can be directly calculated from a very large lattice distance in an infinite-sized system rather than an extrapolated order parameter in a finite-sized system. Therefore, it is worthwhile using this convenient technique to study the non-local orders in the topological phases and characterize the quantum criticalities in the topological quantum phase transitions. In this paper, by utilizing the infinite matrix product state algorithm based on the tensor network representation and infinite time evolving block decimation method, the quantum entanglement, fidelity, and critical exponents of the topological phase transition are investigated in the one-dimensional infinite spin-1 bond-alternating XXZ Heisenberg model. It is found that there is always a local dimerization order existing in the whole parameter range when the bond-alternative strength parameter changes from 0 to 1. Also, due to the effect of the bond-alternating, there appears a quantum phase transition from the long-rang ordering topological Nel phase to the local ordering dimerization phase. The von Neumann entropy, fidelity per lattice site, and order parameters all give the same phase transition point at c = 0.638. To identify the type of quantum phase transition, the central charge c 0.5 is extracted from the ground state von Neumann entropy and the finite correlation length, which indicates that the phase transition belongs to the two-dimensional Ising universality class. Furthermore, it is found that the Nel order and the susceptibility of Nel order have power-law relations to |-c|. From the numerical fitting of the Nel order and its susceptibility, we obtain the characteristic critical exponents ' = 0.236 and ' = 0.838. It indicates that such critical exponents from our method characterize the nature of the quantum phase transition. Our critical exponents from the iMPS method can provide guidance for studying the properties of the phase transition in quantum spin systems.
- Published
- 2017
50. Gaussian phase transition and critical exponents in spin-1 bond-alternative Heisenberg chains
- Author
-
Yao Heng Su, Ai Min Chen, Cai-Juan Xia, Chunhuan Xiang, Jun Wang, and Honglei Wang
- Subjects
Statistics and Probability ,Quantum phase transition ,Phase transition ,Heisenberg model ,Statistical and Nonlinear Physics ,Quantum entanglement ,01 natural sciences ,010305 fluids & plasmas ,Quantum mechanics ,Quantum critical point ,0103 physical sciences ,Statistics, Probability and Uncertainty ,010306 general physics ,Critical exponent ,Critical dimension ,Matrix product state ,Mathematics - Abstract
The quantum Gaussian phase transition is investigated for the infinite spin-1 bond-alternative Heisenberg model in one spatial dimension. By using a tensor network representation with an infinite matrix product state approach, the ground state energy, bipartite entanglement entropy, non-local string order, and fidelity per lattice site are calculated to characterize the phase transition. At the quantum phase transition point, the scaling behavior of various physical observables with respect to the finite truncation dimension are discussed for the ground state wavefunctions. In addition, the central charge is extracted from the finite entanglement entropies and the finite correlation lengths. Furthermore, the various critical exponents of the string order are calculated. The characteristic critical exponents and the central charge determine the universality class of the phase transition.
- Published
- 2016
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