116,644 research outputs found
Chi-Yi Chen — Movimientos migratorios en Venezuela
No full textT. G. Chi-Yi Chen — Movimientos migratorios en Venezuela. In: Population, 24ᵉ année, n°3, 1969. p. 594
High T-g, melt processable copolyimides based on isomeric 3,3' and 4,4'-hydroquinone diphthalic anhydride (HQDPA)
No full textTo extend the upper operating temperature range of melt processable PIs, two series of end-capped copolyimides based on hydroquinone diphthalic anhydride (HQDPA) isomers were designed by varying the contents of appropriate diamines. Thus, copolyimides PI-(0a similar to 20a) based on 3,3'-HQDPA were prepared by varying the ratio of rigid 2-(4-aminophenyl)-5-aminobenzimidazole (BIA) and flexible 4,4'-oxydianiline (ODA). The resulting copolyimides demonstrated good properties, such as excellent solubility, high T-g ranging from 328 to 354 degrees C as determined by dynamic mechanical analyzer (DMA), besides, exhibited good thermal stability based on 5% weight loss temperature (T-5%) of 502-514 degrees C and low melt viscosity in the range of 291-935 Pa.s. Most importantly, PI-20a showed a good combination of low melt viscosity simultaneously with significantly high T-g (328 degrees C). Furthermore, this system was modified by copolymerization with different feed ratio of 4,4'-HQDPA isomer and produced another series PI-(20a similar to 20e), that exhibited high T-g in the range of 315-330 degrees C with T-5% of 502-543 degrees C and minimum complex viscosity in the range of 291-479 Pa.s. All PIs form tough and flexible films that have remarkable tensile strength and moduli in the range of 93-116 MPa and 3.7-4.7 GPa, respectively. (C) 2017 Elsevier Ltd. All rights reserved
Selective tumor cell death induced by irradiated riboflavin through recognizing DNA G-T mismatch
No full textRiboflavin (vitamin B2) has been thought to be a promising antitumoral agent in photodynamic therapy, though the further application of the method was limited by the unclear molecular mechanism. Our work reveals that riboflavin was able to recognize G-T mismatch specifically and induce singlestrand breaks in duplex DNA targets efficiently under irradiation. In the presence of riboflavin, the photo-irradiation could induce the death of tumor cells that are defective in mismatch repair system selectively, highlighting the G-T mismatch as potential drug target for tumor cells. Moreover, riboflavin is a promising leading compound for further drug design due to its inherent specific recognition of the G-T mismatch
Chen Chi Yi, Picouet Michel — Dinamica de la poblacion. Caso de Venezuela
No full textT. G. Chen Chi Yi, Picouet Michel — Dinamica de la poblacion. Caso de Venezuela. In: Population, 36ᵉ année, n°6, 1981. pp. 1199-1200
Phortica FLOCCIPES CAO & CHEN 2009, SP. NOV.
No full textPHORTICA FLOCCIPES CAO & CHEN SP. NOV. (FIGS 1, 8, 13–15) Material examined: Holotype male, CHINA: Dajiuhu, Shennongjia, Hubei, 3.viii.2005, H. W. Chen (SCAU, No. 120020). Paratypes: CHINA: four males, three females, same data as holotype except 3–5.viii.2005, H. Z. Cao, H. W. Chen, and M. F. Xu (one male and one female in KIZ; the rest in SCAU, Nos 120021–25); two males, two females, Miyaluo, Lixian, Sichuan, 8–10.ix.2005, M. F. Xu and H. L. Cao (SCAU, Nos 120026–29). Description: Male and female. Head: frons black, with grey pollinosity. Thorax: scutum almost black, with grey pollinose pattern. Scutellum black, with a pair of yellow patches submedially. Legs: hind tibiae with three black rings, three irregular rows of suberect setae on ventral surface, which are slightly shorter than tibia width (Fig. 2A), apically with one long curved seta (Fig. 2B). All fourth and fifth tarsomeres black, the rest grey-yellow. Male terminalia: cercus with two strong setae (Fig. 14). Surstylus medially protrudent, with two rows of about seven to eight prensisetae, apically round, with four prensisetae (Fig. 14). Paramere submedially with three small processes, two of them with sensillum, apically with one sensillum; basal process with fine sawteeth (Fig. 15). A KEY TO SPECIES OF THE PHORTICA HANI SPECIES COMPLEX (MALES) 1. Arista with only short dorsal branches; wing R 4+5 and M 1 veins nearly parallel; fifth sternite notched posteromedially; cercus ventrally with two to three long, strong setae; paramere with one spike-like process basally; aedeagus nearly membranous (Phortica hani complex)..........................................................................................2 2. Hindleg tibia lacking a long seta apically (males only known); surstylus with one prensiseta apically; basal spike-like process of paramere lacking fine sawteeth............................................................................... 3 – Hindleg tibia with a long seta apically; surstylus apically with two prensisetae at least; basal process of paramere with fine sawteeth.............................................................................................................................4 3. Surstylus apically truncate; cercus ventrally with three long setae......................................................................................................................................................... Phortica longicauda Cao & Chen sp. nov. – Surstylus apically pointed; cercus ventrally with two long setae......... Phortica longiseta Cao & Chen sp. nov. 4. Hindleg tibia apically with one row of short, scopiform setae on ventral surfaces (male only known); surstylus with two prensisetae apically.................................................................. Phortica panda Cao & Chen sp. nov. – Hindleg tibia lacking scopiform setae apically; surstylus with three prensisetae at least................................5 5. Hindleg tibiae with three black rings and two to three rows of suberect setae on ventral surface, lacking long setae on posteroventral surface; surstylus not covered by epandrium..................................................................6 – Hindleg tibiae with two rings, lacking fringe-like setae on ventral surface, with one row of long setae on posteroventral surface, surstylus covered by epandrium........................................................................... 7 6. Fringe-like setae of hindleg tibiae as long as 1.5¥ of tibia width; surstylus medially not protrudent, with two prensisetae.................................................................................................. Phortica hani (Zhang & Shi) – Fringe-like setae of hindleg tibiae shorter than tibia width; surstylus medially protrudent, with seven to eight prensisetae arranged in two rows.................................................. Phortica floccipes Cao & Chen sp. nov. 7. Scutellum orange-brown, black along margin; hindleg tibia basally to apically with one row of about 11 long setae on anteroventral surface which are about as long as the tibia width......................................................................................................................................................... Phortica hirtotibia Cao & Chen sp. nov. – Scutellum entirety blackish; hind tibiae distally with one row of about eight strong setae on anteroventral surface, most of which are shorter than the tibia width............................. Phortica pinguiseta Cao & Chen sp. nov. A KEY TO PHORTICA HANI SPECIES COMPLEX BASED ON ND2 AND COI SEQUENCES In the following key to seven species of the P. hani complex, character statuses at diagnostic sites were compared between a given pair of taxa. Each status depiction starts with a letter denoting its affiliated gene (N: ND2; C: COI), followed by a number (in subscript) indicating the site positions in the sequences of the affiliated gene, and then by the codon position of the site (in parentheses and in subscript), the nucleotide type (after a colon), and the corresponding amino acid type (after a slash, all shown by standard three-letter abbreviations). No character was found to diagnose between P. floccipes and P. panda based on their ND2 or COI sequences. 1. N 330 (3rd): A/Leu; N 627 (3rd): A/Leu; N 919 (1st): A/Met; C 204 (3rd): A/Val; C 534 (3rd): T/Arg; C 574 (1st): C/Leu; C 627 (3rd): T/Thr; C 705 (3rd): T/Phe; C819 (3rd):T/Tyr; C 894 (3rd): C/Asp; C1002 (3rd): A/Pro................................................................................2 – N330 (3rd): T/Phe; N627 (3rd): T/Phe; N919 (1st): G/Val; C204 (3rd): T/Val; C534 (3rd): A/Arg; C574 (1st): T/Leu; C627 (3rd): A/Thr; C705 (3rd): C/Phe; C819 (3rd): C/Tyr; C 894 (3rd): T/Asp; C1002 (3rd): G/Pro.............................................................................. 4 2. N292 (1st): G/Val; N605 (2nd): C/Thr; N996 (3rd): A/Met; C72 (3rd): C/Ala; C279 (3rd): T/Pro; C402 (3rd): C/Ile; C573 (3rd): T/Phe; C756 (3rd): T/Ile; C805 (1st): C/Leu; C1083 (3rd): C/Val; C1201 (1st): T/Leu; C1335 (3rd): T/Tyr........................................................................................................................................................... Phortica longiseta Cao & Chen sp. nov. – N 292 (1st): A/Met; N 605 (2nd): T/Ile; N 996 (3rd): T/Ile; C 72 (3rd): T/Ala; C 279 (3rd): C/Pro; C 402 (3rd): T/Ile; C 573 (3rd): C/Phe; C 756 (3rd): C/Ile; C805 (1st): T/Leu; C1083 (3rd): T/Val; C1201 (1st): C/Leu; C1335 (3rd): C/Tyr................................................................... 3 3. N144 (3rd): C/Asn; N333 (3rd): T/His; C1023 (3rd): A/Gly; C1089 (3rd): T/Ile........... Phortica pinguiseta Cao & Chen sp. nov. – N144 (3rd): T/Asn; N333 (3rd): C/His; C1023 (3rd): G/Gly; C1089 (3rd): C/Ile............ Phortica hirtotibia Cao & Chen sp. nov. 4. N441 (3rd): A/Lys; N444 (3rd): T/Pro; N795 (3rd): A/Gln; N810 (3rd): C/Asn; C201 (3rd): A/Met; C456 (3rd): T/Gly; C474 (3rd): A/Gly; C537 (3rd): A/Met; C 648 (3rd): C/Ser; C 747 (3rd): T/Phe............................................................................................................................................... Phortica floccipes Cao & Chen sp. nov. / Phortica panda Cao & Chen sp. nov. – N 441 (3rd): G/Lys; N 444 (3rd): C/Pro; N 795 (3rd): G/Gln; N 810 (3rd): T/Asn; C 201 (3rd): G/Met; C 456 (3rd): A/Gly; C 474 (3rd): G/Gly; C 537 (3rd): G/Met; C648 (3rd): T/Ser; C747 (3rd): C/Phe.....................................................................................................5 5. N405 (3rd): C/Ile; N 603 (3rd): C/Phe; N651 (3rd): C/Thr; N774 (3rd): T/Pro; N915 (3rd): T/Asn; C513 (3rd): C/Ala; C594 (3rd): T/Pro; C855 (3rd): G/Val; C1218 (3rd): A/Lys.................................................................................... Phortica hani (Zhang & Shi) – N405 (3rd): T/Ile; N 603 (3rd): T/Phe; N651 (3rd): T/Thr; N774 (3rd): A/Pro; N915 (3rd): C/Asn; C513 (3rd): T/Ala; C594 (3rd): G/Pro; C855 (3rd): T/Val; C 1218 (3rd): G/Lys............................................................... Phortica longicauda Cao & Chen sp. nov. Measurements: BL = 3.70 mm in holotype (range in four male and five female paratypes: 3.50–4.20); ThL = 1.75 mm (1.60–2.00); WL = 3.30 mm (3.05– 3.60); WW = 1.35 mm (1.30–1.75). Indices: arb = 3/0 (3–6/0), adf = 0.79 (0.53–0.79), flw = 1.64 (1.54–2.00), FW/HW = 0.50 (0.49–0.53), ch/o = 0.13 (0.12–0.14), prorb = 1.21 (1.00–1.33), rcorb = 0.52 (0.38–0.53), vb = 0.36 (0.32–0.59), dcl = 0.52 (0.49– 0.62), presctl = 0.44 (0.44–0.57), sctl = 1.05 (1.03– 1.07), sterno = 0.81 (0.65–0.94), orbito = 1.70 (1.46–1.67), dcp = 0.26 (0.19–0.30), sctlp = 0.87 (0.72– 0.96), C = 2.54 (2.57–3.24), 4c = 1.37 (1.07–1.26), 4v = 2.50 (2.25–2.65), 5x = 0.88 (0.68–1.10), ac = 2.25 (1.69–2.08), M = 0.65 (0.49–0.76), C3F = 0.56 (0.43– 0.60). Etymology: A combination of the Latin words floccus and pes, referring to the hindleg tibia with suberect setae. Distribution: China (Hubei, Sichuan). A KEY TO SPECIES OF THE PHORTICA HANI SPECIES COMPLEX (MALES) 1. Arista with only short dorsal branches; wing R 4+5 and M 1 veins nearly parallel; fifth sternite notched posteromedially; cercus ventrally with two to three long, strong setae; paramere with one spike-like process basally; aedeagus nearly membranous (Phortica hani complex)..........................................................................................2 2. Hindleg tibia lacking a long seta apically (males only known); surstylus with one prensiseta apically; basal spike-like process of paramere lacking fine sawteeth............................................................................... 3 – Hindleg tibia with a long seta apically; surstylus apically with two prensisetae at least; basal process of paramere with fine sawteeth.............................................................................................................................4 3. Surstylus apically truncate; cercus ventrally with three long setae......................................................................................................................................................... Phortica longicauda Cao & Chen sp. nov. – Surstylus apically pointed; cercus ventrally with two long setae......... Phortica longiseta Cao & Chen sp. nov. 4. Hindleg tibia apically with one row of short, scopiform setae on ventral surfaces (male only known); surstylus with two prensisetae apically.................................................................. Phortica panda Cao & Chen sp. nov. – Hindleg tibia lacking scopiform setae apically; surstylus with three prensisetae at least................................5 5. Hindleg tibiae with three black rings and two to three rows of suberect setae on ventral surface, lacking long setae on posteroventral surface; surstylus not covered by epandrium..................................................................6 – Hindleg tibiae with two rings, lacking fringe-like setae on ventral surface, with one row of long setae on posteroventral surface, surstylus covered by epandrium........................................................................... 7 6. Fringe-like setae of hindleg tibiae as long as 1.5¥ of tibia width; surstylus medially not protrudent, with two prensisetae.................................................................................................. Phortica hani (Zhang & Shi) – Fringe-like setae of hindleg tibiae shorter than tibia width; surstylus medially protrudent, with seven to eight prensisetae arranged in two rows.................................................. Phortica floccipes Cao & Chen sp. nov. 7. Scutellum orange-brown, black along margin; hindleg tibia basally to apically with one row of about 11 long setae on anteroventral surface which are about as long as the tibia width......................................................................................................................................................... Phortica hirtotibia Cao & Chen sp. nov. – Scutellum entirety blackish; hind tibiae distally with one row of about eight strong setae on anteroventral surface, most of which are shorter than the tibia width............................. Phortica pinguiseta Cao & Chen sp. nov.Published as part of He, Xiaofang, Gao, Jianjun, Cao, Huazhi, Zhang, Xiaolei & Chen, Hongwei, 2009, Taxonomy and molecular phylogeny of the Phortica hani species complex (Diptera: Drosophilidae), pp. 359-372 in Zoological Journal of the Linnean Society 157 (2) on pages 362-364, DOI: 10.1111/j.1096-3642.2009.00516.x, http://zenodo.org/record/468781
Effect of polyethylene interface on space charge formation
No full textThis paper reports the results of an investigation into the space charge formation and decay at different material interfaces. In particular, the influence of the interface between electrode and polymer or polymer and polymer on the space charge dynamics has been studied. Planar samples were subjected to high dc electric stresses for extended periods of time and space charge measurements taken using the pulsed electroacoustic (PEA) technique. It has been found that the types of interface between electrode and polymer play a significant role in determining the charge distribution in the insulation and that the interface between polymer and polymer acts as a potential barrier to electrons whilst allowing positive charge carriers through easily
Corrigendum to “General reduced vehicle model for simulating truck-bridge pier collisions” [Dev. Built. Environ. 16 (2023) 100233] (Developments in the Built Environment (2023) 16, (S2666165923001151), (10.1016/j.dibe.2023.100233))
No full textThe authors regret there were two errors in the authors' affiliation in the published article. First, the affiliation of the first author (Daogang Ou) should only be the School of Civil Engineering, Hunan University of Science and Technology, Xiangtan, 411201, China. Second, the corresponding author (Lin Chen) should have two affiliations; the first one should be: School of Civil Engineering, Hunan University of Science and Technology, Xiangtan, 411201, China; and the second one should be: Key Laboratory of Building Safety and Energy Efficiency of Ministry of Education, Hunan University, Changsha, 410082, China. The authors would like to apologise for any inconvenience caused
The circumference of a graph with no K3, t-minor
No full textIt was shown by Chen and Yu that every 3-connected planar graph G contains a cycle of length at least | G |log 3 2, where | G | denotes the number of vertices of G. Thomas made a conjecture in a more general setting: there exists a function β (t) > 0 for t ≥ 3, such that every 3-connected graph G with no K3, t-minor, t ≥ 3, contains a cycle of length at least | G |β (t). We prove that this conjecture is true with β (t) = log8 t t + 1 2. We also show that every 2-connected graph with no K2, t-minor, t ≥ 3, contains a cycle of length at least | G | / tt - 1. © 2006 Elsevier Inc. All rights reserved.preprin
Resonantly enhanced Faraday rotation in a microcoil current sensor
No full textA proof-of-principle experimental demonstration with theoretical modeling is presented for resonantly enhanced Faraday rotation in a microcoil current sensor. The recirculation of resonant light within the coil gives rise to an accumulated polarization rotation and thus improved responsivity. According to simulations, microcoil resonators with sharper resonances could offer significantly larger enhancements. This new type of current sensor has the potential to be ultrafast, compact, and low-cost
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