50,260 research outputs found
Motivations and strategies for a real revaluation of the Yuan.
Full text linkMost Western economists and policymakers agree that the Yuan is significantly undervalued and push for its quick nominal revaluation. This paper defends that many domestic and foreign factors could be responsible for the Yuan’s undervaluation, and the People’s bank of China (PBC) cannot optimally invest growing foreign exchange reserves. It provides a theoretical framework to discuss the optimal strategy associating a gradual nominal revaluation of the Yuan with higher inflation, and structural and macroeconomic policies to bring the real exchange rate to its equilibrium level. This strategy allows absorbing external imbalances while laying down the foundation for China’s long-term growth.Real revaluation; Yuan; Renminbi (RMB); foreign exchange reserves; external imbalance; macroeconomic adjustment measures.
畫答 / (意)畢方濟撰 ; 孫元化訂
No full textComprend : Shui da / (Yi) Bi fag ji zhuan ; Sun Yuan hua ding - 睡答 / (意)畢方濟撰 ; 孫元化訂Avec mode text
“CAN'T HELP MYSELF”: BODY, SOUL, MACHINE. The art by Sun Yuan and Peng Yu as a form of obsessive-compulsive disorder.
No full textreservedAnalisi dell'opera “Can't Help Myself”, realizzata nel 2016 dalla coppia di artisti cinesi Sun Yuan e Peng Yu. Partendo da una panoramica sulla carriera dei due artisti, con qualche riferimento allo sviluppo dell'arte contemporanea cinese, viene descritta la storia dietro la costruzione dell'opera insieme alle dichiarazioni della coppia. In seguito, un approfondimento sul contesto intorno all'opera vede un confronto tra le due mostre a cui è stata esposta (Tales Of Our Time a New York nel 2016 e la Biennale d'arte di Venezia del 2019). In conclusione, uno sguardo alla ricezione e alla critica, analizzando le molteplici interpretazioni sul significato, il fenomeno mediatico che ha fatto diventare quest'opera virale online e collegamenti con temi di attualità
Motivations and strategies for a real revaluation of the Yuan
Full text linkMost Western economists and policy makers agree that the Yuan is significantly undervalued and push the Chinese government for a large nominal revaluation of the Yuan. This paper, while surveying recent research on Chinese exchange rate policy, gives some new insights into this issue. Notably, this paper defends that China is not solely responsible for the Yuan’s undervaluation, the Chinese central bank cannot optimally invest an increasing amount of foreign currency reserves, and the Yuan’s nominal revaluation is not the only way to resolve the problem. After having analyzed the advantages and disadvantages of a nominal versus a real revaluation of the Yuan for the Chinese economy, I advocate and analyze, besides a modest nominal revaluation, a multitude of alternative policies to achieve a complete revaluation of the Yuan in real terms, which allows absorbing external disequilibrium while laying down the foundation for the long-term growth of the Chinese economy.Renminbi (RMB), revaluation of the Yuan, foreign exchange reserves, external disequilibrium, measures of macroeconomic adjustment.
Amynthas yuanjiangensis Sun & Jiang & Wu & Yuan & Qiu 2021, sp. nov.
No full textAmynthas yuanjiangensis Sun & Qiu, sp. nov. (Fig. 4) Type material. Holotype: One clitellate specimen (C-YN201102-01), China, Yunnan Province, Yuanjiang National Nature Reserve (23°39ʹ54ʺN, 101°46ʹ29ʺE), 2096 m asl, by the side of a ditch, under chestnut tree, yellow cinnamon soil; Jul. 16, 2011; J. B. Jiang, J. Sun, X. D. Lei, and H. W. Feng coll. Paratypes: A total of 55 specimens, as follows: One clitellate (C-YN201703-01), China, Yunnan Province, Yulong Snow Mountain Provincial Nature Reserve (27°12ʹ19.6ʺN, 100°16ʹ47.7ʺE), 1451 m asl; Aug. 2, 2017; J. B. Jiang, Y. Dong, Q. Zhao, and Z. Yuan coll. Nine clitellates (C-YN201713-06), China, Yunnan Province, Wuliangshan Nature Reserve (24°46ʹ22.9ʺN, 100°31ʹ12.4ʺE), 2158 m asl; Aug. 5, 2017; J. B. Jiang, Y. Dong, Q. Zhao, and Z. Yuan coll. Nine clitellates (C-YN201719-01), China, Yunnan Province, Dali City, Cangshan National Nature Reserve (25°46ʹ55.1ʺN, 100°05ʹ27.4ʺE), 2364 m asl; Aug. 6, 2017; J. B. Jiang, Y. Dong, Q. Zhao, and Z. Yuan coll. Four clitellates (C-YN201722-01), China, Yunnan Province, Dali City, Yunlong Tianchi National Nature Reserve (25°51ʹ42.1ʺN, 99°17ʹ00.7ʺE), 2621 m asl; Aug. 7, 2017; J. B. Jiang, Y. Dong, Q. Zhao, and Z. Yuan coll. Two clitellates (C-YN201735-08), China, Yunnan Province, Dehong Dai and Jingpo Autonomous Prefecture, Tongbiguan Provincial Nature Reserve (24°08ʹ56.3ʺN, 98°01ʹ31.0ʺE), 957 m asl; Aug. 11, 2017; J. B. Jiang, Y. Dong, Q. Zhao, and Z. Yuan coll. Two clitellates (C-YN201749-01), China, Yunnan Province, Yongdedaxueshan Nature Reserve (25°09ʹ03.1ʺN, 99°42ʹ31.4ʺE), 2122 m asl, 14 Aug. 2017; J. B. Jiang, Y. Dong, Q. Zhao, and Z. Yuan coll. One clitellate (C-YN201756-04), China, Yunnan Province, Lincang City, Nangunhe National Nature Reserve (23°38ʹ58.3ʺN, 99°20ʹ32.9ʺE), 1429 m asl; Aug. 16, 2017; J. B. Jiang, Y. Dong, Q. Zhao, and Z. Yuan coll. Two clitellates (C-YN201762-05), China, Yunnan Province, Lincang City, Nangunhe National Nature Reserve (23°18ʹ54.9ʺN, 99°13ʹ14.4ʺE), 2129 m asl; Aug. 17, 2017; J. B. Jiang, Y. Dong, Q. Zhao, and Z. Yuan coll. Nine clitellates and four aclitellates (C-YN201627-02), China, Yunnan Province, Pu’er City, Jingdong Yi Autonomous County (24°16ʹ09.5ʺ N, 100°45ʹ37.3ʺ E), 1860 m asl, in black sandy soil; Jul. 30, 2016; X. Gao, Y. F. Lu, J. Z. Jiang, J. Long coll. Two clitellates and three aclitellates (C-YN201703-01), China, Yunnan Province, Lijiang City, Yulong Snow Mountain Provincial Nature Reserve (27°12ʹ07.2ʺN, 100°16ʹ51.9ʺE), 3140 m asl, in yellow soil; Aug. 2, 2017; Z. Yuan, J. B. Jiang, Y. Dong, Q. Zhao coll. Four clitellates (C-YN201722-01), China, Yunnan Province, Dali City, Yunlong Tianchi National Nature Reserve (25°51ʹ30.7ʺN, 99°17ʹ03.7ʺE), 2621 m asl, in brown soil; Aug. 7, 2017; Z. Yuan, J. B. Jiang, Y. Dong, Q. Zhao coll. Six aclitellates (C-YN201756-04), China, Yunnan Province, Lincang City, Nangunhe National Nature Reserve (23°38ʹ49.0ʺN, 99°20ʹ36.6ʺE), 1429 m asl, in yellow cinnamon soil; Aug. 16, 2017; Z. Yuan, J. B. Jiang, Y. Dong, Q. Zhao coll. Two clitellates (C-YN201735-08), China, Yunnan Province, Dehong Dai and Jingpo Autonomous Prefecture, Tongbiguan Provincial Nature Reserve (24°08ʹ46.1ʺN, 98°01ʹ32.3ʺE), 957 m asl, in brown soil; Aug. 11, 2017; Z. Yuan, J. B. Jiang, Y. Dong, Q. Zhao coll. Two clitellates (C-YN201762-05), China, Yunnan Province, Lincang City, Nangunhe National Nature Reserve (23°18ʹ45.2ʺN, 99°13ʹ17.4ʺE), 2129 m asl, in brown soil; Aug. 17, 2017; Z. Yuan, J. B. Jiang, Y. Dong, Q. Zhao coll. The habitats of the paratypes were not recorded in detail. Etymology. The name yuanjiangensis is derived from the collection site (Yuanjiang National Nature Reserve) of the holotype. In Chinese, Amynthas yuanjiangensis is Kmũ Ḃḋ. Diagnosis. Medium-sized; four pairs of spermathecal pores in 5/6–8/9; each male pore on the top of a large raised pulvinate pad; no genital papillae in the spermathecal pore and male pore regions; prostate gland partially vestigial in 1/2 XVII–1/2 XIX, or developed; spermathecal diverticulum about ¾ as long as the main spermathecal axis, distal U dilated into a rod-shaped seminal chamber. Description. External characters: Preserved specimens yellowish-brown on dorsum, lacking pigment on ventrum. Mid-dorsal line pigmented. Dimensions 80–135 mm by 3.0–5.0 mm at clitellum; segments 82–110. Secondary annulations present in VI–XIII. Prostomium ¾ epilobous. First dorsal pore in 11/12. Clitellum annular, in XIV–XVI, gray-brown, smooth, swollen, no setae on the ventral side; dorsal pores absent but with vestiges on clitellum. Setae uniformly distributed, 22–30 at III, 30–36 at V, 32–36 at VIII, 38–48 at XX, 46–62 at XXV; 7–9/VII, 7–14/VIII between spermathecal pores, 7–12 between male pores; setal formula AA=1.0–1.2AB, ZZ=1.2–1.3ZY. Spermathecal pores four pairs in 5/6–8/9 (Fig. 4a, sp.p), ventrally separated by slightly more than 0.33 of circumference. Male pores in XVIII, ventrally separated by 0.25 of circumference, each on top of a large raised pulvinate pad, surrounded by two skin folds medially and one rhombus-shaped skin fold laterally in the holotype (Fig. 4a, mp), but no skin fold in paratypes. No genital papillae in male pore region. Female pore single, mid-ventral in XIV, elliptical. Internal characters: Septa 8/9–9/10 absent, 5/6–7/8 thickened and muscular, 10/11–14/15 thicker than those following. Dorsal blood vessel single, continuous onto pharynx; esophageal hearts 4 pairs in X–XIII, all developed. Gizzard bucket-like, in VIII–X; intestinal swelling in XV. Intestinal caeca between simple and complex, originating in XXVII and extending forward to 1/2XXIII, horn-shaped sacs; tiny incisions deeper on dorsal margin than on ventral margin in holotype (Fig. 4b); tiny incisions only on dorsal margin in paratypes C-YN201703-01, CYN201703 -01, C-YN201719-01, and C-YN201735-08. Male organs: testis sacs in X and XI; oval, developed, two lobes connected ventromedially in the first pair and separated ventromedially in the second pair; two pairs of seminal vesicles in XI and XII, first pair separated ventromedially, second pair connected with a slim tube; in holotype, left prostate gland located in 1/2 XVII–1/2 XIX and degenerated into a small and compact lobe, right prostate gland pachytic and developed (Fig. 4c), its duct in XVIII, U-shaped, stout ventrally; prostate glands vestigial in paratypes C-YN201703-01, C-YN201719-0, and C-YN201735-08, but developed in paratype C-YN201713-06; no visible accessory glands on XVIII. Spermathecae paired in VI–IX, about 2.7 mm long; spermathecal ampulla heart-shaped, 2.1 mm long; in holotype, diverticulum about 3/4 as long as the main spermathecal axis, distal 2/5 dilated into a rodshaped seminal chamber; in paratypes C-YN201703-01, C-YN201713-06, C-YN201722-01, and C-YN201735-08, diverticulum about 1/2 as long as the main spermathecal axis, distal 1/2–1/3 dilated into rod-shaped seminal chamber; in paratype C-YN201719-01, diverticulum about 2/5 as long as the main spermathecal axis, distal 1/3 dilated into rod-shaped seminal chamber; no nephridia on spermathecal ducts (Fig. 4d). Variation. The prostate glands are either degenerated or developed. DNA barcodes. GenBank accession numbers KF205466 (C-YN201102-01, holotype), MH 845539 (CYN201703 -01, paratype), MH 845531 (C-YN201713-06, paratype), MH 845522 (C-YN201719-01, paratype), MH 845514 (C-YN201722-01, paratype), MH 845487 (C-YN201735-08, paratype), MH 845470 (C-YN201749- 01, paratype), MH 845460 (C-YN201756-04, paratype), MH 845451 (C-YN201762-05, paratype), MH 837679 (C-YN201627-02, paratype), MH 845539 (C-YN201703-01, paratype), MH 845514 (C-YN201722-01, paratype), MH 845460 (C-YN201756-04, paratype), MH 845487 (C-YN201735-08, paratype), MH 845451 (C-YN201762-05, paratype). Remarks. A. yuanjiangensis sp. nov. keys to the Amynthas corticis -group (Sims & Easton, 1972), characterized by four spermathecal pores located intersegmentally in 5/6–8/9 and by holandry. By now, there are 109 species belonging into A. corticis -group totally (Nguyen et al. 2020a). The combined characters of medium-sized body, male pore on the top of a large raised pulvinate pad, no genital papillae in the spermathecal pore and male pore regions, intestinal caeca between simple and complex, prostate gland partially vestigial or developed, and rod-shaped spermathecal seminal chamber make this new species different from the species reported from China in A. corticis -group. This new species is similar to Amynthas fornicates (Gates, 1935) in medium-sized body, no genital papillae in the male pore region, and the arrangement of spermathecal pores. However, in A. yuanjiangensis sp. nov., the intestinal caeca are between simple and complex, the prostate glands are partially degenerated, and the spermathecal diverticulum shorter than the main spermathecal axis; however, in A. fornicates, the intestinal caeca are simple, the prostate glands are developed, and the spermathecal diverticulum is longer than the main spermathecal axis. A. yuanjiangensis sp. nov. is resemble Amynthas homochaetus (Chen, 1938) in the large raised pulvinate pad of male pore area, no genital papillae on spermathecal pore region and male pore region especially. But A. yuanjiangensis sp. nov. is clearly distinguished from A. homochaetus by the following characters: 1) the intestinal caeca in A. homochaetus are simple, but in this new species, they are between simple and complex; 2) the prostate glands in A. homochaetus are well developed, but in the new species, they are partially degenerated; 3) the seminal chambers in A. homochaetus are ovoid, but those in the new species are rod-shaped. Amynthas disperses Sun & Qiu, 2018 and A. yuanjiangensis sp. nov. have both been collected in several localities in South China, and share some characters (e.g. megium-sized body, the area of male pore porophore is bigger, partially vestigial prostate gland, and band- or rod-shaped seminal chamber), but they are different from each other in the following ways: 1) the first dorsal pore is located at 10/11 or 11/12 on A. disperses, but always at 11/ 12 in the new species; 2) small genital papillae are always present in the spermathecal pore and male pore region in A. disperses, but there are no genital papillae in the new species; 3) the intestinal caeca in A. disperses are simple, but those in this new species are between simple and complex; 4) the spermathecal diverticulum is about as long as the main spermathecal axis in A. disperses, but shorter than the main spermathecal axis in the new species.Published as part of Sun, Jing, Jiang, Ji-Bao, Wu, Juzhen, Yuan, Zhu & Qiu, Jiang-Ping, 2021, Three new widely distributed and polymorphic species of Amynthas earthworms (Oligochaeta, Clitellata, Megascolecidae) from South China, pp. 457-474 in Zootaxa 4938 (4) on pages 464-467, DOI: 10.11646/zootaxa.4938.4.5, http://zenodo.org/record/457494
Dataset for article - Effects of ammonia on propionate degradation and microbial community
No full textLi Y., Zhang Y., Kong X., Li L., Yuan Z., Dong R. and Sun Y. (2017) Effects of ammonia on propionate degradation and microbial community in digesters using propionate as a sole carbon source. Journal of Chemical Technology and Biotechnology. Accepted on 23 Feb 2017.
Fig 1. Propionic acid degradation performance of reactors.
Fig 2. Relative abundance of archaea 16S rRNA gene at the order level and genus level.
Fig 3. Relative abundance of bacteria 16S rRNA gene at the phylum level and class s level.
Table 2. Comparision of the dominant functional groups for propionate degradation and methane production.</span
Feasibility of Software-Based Duty Cycling of GPS for Trajectory-Based Services
No full textEnergy-efficient localization is increasingly important for many types of smartphone apps. The research community has argued that fixed duty cycling of GPS is not a good choice for trajectory-based services concerning route accuracy. In this paper, we describe the design and implementation of a highly accurate map matching and path construction algorithm. Furthermore, with thorough field experiments, we show that fixed duty cycling of a smartphone GPS receiver is a feasible approach for trajectory-based services, and it can achieve considerable energy conservation without sacrificing much route accuracy. When increasing the GPS sampling period beyond 120 seconds, it saves at least 78% energy in comparison to continuous GPS sampling, while the loss of route accuracy tends to be stable around 23%.Li, Xiaohan, Yuan, Fengpeng, & Lindqvist, Janne. (2016). Feasibility of Software-Based Duty Cycling of GPS for Trajectory-Based Services. In Proceedings of Consumer Communications & Networking Conference (CCNC2016-EdgeCom), Las Vegas, NV. http://ieeexplore.ieee.org/xpl/conhome.jsp?reload=true&punumber=1001153Peer reviewe
Ping jing guan cong shu /
No full textDouble leaves, oriental style, in case.Lanling Sun zhi xing yan yuan ban ; Wu Xian Zhu shi huai lu jia shu cang ban.Mode of access: Internet
Amynthas rusticanus Sun & Jiang & Wu & Yuan & Qiu 2021, sp. nov.
No full textAmynthas rusticanus Sun & Qiu, sp. nov. (Fig. 2) Type material. Holotype: One clitellate specimen (C-YN201108-02A), China, Yunnan Province, Xishuangbanna Dai Autonomous Prefecture, Mengla County (21°35ʹ03ʺN, 101°34ʹ58ʺE), 722m above sea level (asl), under fern and shrub, laterite; Jul. 20, 2011; J. B. Jiang, J. Sun, X. D. Lei, and H. W. Feng coll. Paratypes: A total of 29 specimens, as follows: Two clitellates (C-YN201108-02B), same collection details as holotype. One clitellate (C-YN201101-18), China, Yunnan Province, Yuanjiang National Nature Reserve (23°40ʹ09ʺN, 101°51ʹ05ʺ E), 854 m asl, under fruit trees (longan, mango, and plum), lateritic red soil; Jul. 16, 2011; J. B. Jiang, J. Sun, X. D. Lei, and H. W. Feng coll. One clitellate (C-YN201107-11), China, Yunnan Province, Xishuangbanna Dai Autonomous Prefecture, Mengla County (21°36ʹ21ʺN, 101°34ʹ54ʺE), 694 m asl, daisy under trees, laterite; Jul. 20, 2011; J. B. Jiang, J. Sun, X. D. Lei, and H. W. Feng coll. One clitellate (C-YN201109-10), China, Yunnan Province, Xishuangbanna Dai Autonomous Prefecture, Mengla County (21°24ʹ14ʺN, 101°37ʹ27ʺE), 722 m asl, in tropical primary forest, laterite; Jul. 20, 2011; J. B. Jiang, J. Sun, X. D. Lei, and H. W. Feng coll. Five clitellates (C-SC201009-08), China, Sichuan Province, Yibin City, Changning County, Mount Zhuji (28°22ʹ55.3ʺN, 104°52ʹ17.8ʺE), 311 m asl, under Metasequoia, red-yellow soil; Aug. 15, 2010; J. Sun, Z. W. Yi, and J. H. Yi coll. Two clitellates and two aclitellates (C-SCCZ2015003-04), China, Sichuan Province, Chongzhou City, Jinjiang County (30°40ʹ36ʺN, 103°40ʹ59ʺ E), 594 m asl, in secondary forest, red-yellow soil; Jun. 22, 2015; J. Sun, Z. W. Yi, and J. Yu coll. Two clitellates (C-YN201720-01), China, Yunnan Province, Dali City, Cangshan National Nature Reserve (25°46ʹ37.8ʺN, 100°05ʹ42.0ʺE), 2194 m asl, in brown soil; Aug. 6, 2017; Z. Yuan, J. B. Jiang, Y. Dong, Q. Zhao coll. Two clitellates (C-YN201735-10), China, Yunnan Province, Dehong Dai and Jingpo Autonomous Prefecture, Tongbiguan Provincial Nature Reserve (24°08ʹ46.1ʺN, 98°01ʹ32.3ʺE), 957 m asl, in yellow cinnamon soil, 11 Aug. 2017; Z. Yuan, J. B. Jiang, Y. Dong, Q. Zhao coll. Nine clitellates (C-YN201756-05), China, Yunnan Province, Lincang City, Nangunhe National Nature Reserve (23°38ʹ49.0″N, 99°20ʹ36.6ʺE), 1429 m asl, in brown soil; Aug. 16, 2017; Z. Yuan, J. B. Jiang, Y. Dong, Q. Zhao coll. Four clitellates (C-YN201730-03), China, Yunnan Province, Nujiang Lisu Autonomous Prefecture, Gaoligongshan National Nature Reserve (26°32ʹ31.5ʺN, 98°54ʹ50.4ʺE), 1867 m asl, in brown soil; Aug. 9, 2017; Z. Yuan, J. B. Jiang, Y. Dong, Q. Zhao coll. One clitellate (C-YN201752-01), China, Yunnan Province, Lincang City, Yongde Daxueshan National Nature Reserve (23°58ʹ14.9ʺN, 99°23ʹ57.8ʺE), 1572 m asl, in brown soil; Aug. 15, 2017; Z. Yuan, J. B. Jiang, Y. Dong, Q. Zhao coll. Two clitellates (C-YN201606- 03), China, Yunnan Province, Pu’er City, Jingdong Yi Autonomous County (24°25ʹ09.7ʺN, 100°52ʹ44.9ʺE), 1180 m asl, in brown soil; Jun. 11, 2016; X. Gao, Y. F. Lu, J. Z. Jiang, J. Long coll. Etymology. The species name is derived from the Latin word “ rustica ”, meaning rural, because the holotype was collected in a rural area of Yunnan Province, China. In Chinese, Amynthas rusticanus is ØTũḂḋ. Diagnosis. Small-sized; three pairs of spermathecal pores in 5/6–7/8, or two pairs of spermathecal pores in 5/6–6/7; male porophore resembles an oval pad, surrounded by 2–3 shallow skin folds; no genital papillae in the spermathecal pore and male pore regions; prostate gland developed in XVI–XX; spermathecal diverticulum shorter than the main spermathecal axis by ¼, stalk straight or twisted into two zigzags, distal ¼ dilated into a heart- or oval-shaped seminal chamber. Description. External characters: Preserved specimens light fuchsia before clitellum on dorsum, lacking pigment on the rest of the body. Dimensions 40–59 mm by 1.9–2.0 mm at clitellum; segments 91–92. No secondary annulations in any segment. Prostomium ½ epilobous. First dorsal pore in 12/13. Clitellum annular in XIV–0.17XVII in the holotype, XIV–XVI in paratype C-SCCZ2015003-04; smooth, swollen, no setae on the ventral side; dorsal pores absent on clitellum. Setae uniformly distributed, 34–46 on III, 46–60 on V, 50–60 on VIII, 46–48 on XX, 44–50 on XXV; 8–10 between male pores; setal formula AA=1.2–2.0AB, ZZ=1.7–2.0ZY. Spermathecal pores tiny, hard to locate; three pairs in 5/6–7/ 8 in holotype, rarely two pairs in 5/6–6/7 as in paratype C-SCCZ2015003-04; intersegmental, separated ventrally by about 0.33 of circumference (Fig. 2a, sp.p). In holotype, no genital papillae in spermathecal pore region; in paratype C-SCCZ2015003-04, one small genital papilla posterior and medial to each of the left spermathecal pores in VI and VII. Male pores in XVIII, separated ventrally by 0.33 of circumference, slightly elevated from the skin sheath; glandular raised porophore resembles an oval pad, surrounded by 2–3 shallow skin folds (Fig. 2a, mp). No genital papillae in the male pore region. Female pore single, mid-ventral on XIV, milk-white, elliptical. Internal characters: Septa 8/9–9/10 absent, 5/6–7/8 thickened and muscular, 10/11–13/14 thicker than those following. Dorsal blood vessel single, continuous onto pharynx; esophageal hearts 4 pairs in X–XIII, the first pair slimmer than the others. Gizzard ball-shaped, in VIII–X; intestinal swelling in XVI; intestinal caeca simple, originating in XXVII and extending forward to XXII, finger-shaped sacs, smooth on dorsal and ventral margins. Male organs: testis sacs in X and XI, oval, two lobes separated ventromedially; seminal vesicles in XI, XII, developed, left and right lobes connected ventromedially with a slim tube; prostate gland developed, in XVI–XX, its duct in XVIII, horizontally situated, stout and uniform (Fig. 2b); no visible accessory glands on XVIII. Spermathecae paired in VI–VIII in holotype, about 1.7 mm long; spermathecal ampulla peach-shaped, 0.5 mm long, duct long and straight, 1.2 mm long; diverticulum shorter than the main spermathecal axis by ¼, its stalk straight or twisted into two zigzags, distal ¼ dilated into a heart- or oval-shaped seminal chamber; no nephridia on spermathecal ducts. Variation. The configuration of spermathecae varies between two and three pairs, of which three pairs are the dominant group. DNA barcodes. GenBank accession numbers KF205471 (C-YN201108-02A, holotype), MF541643 (CYN201101 -18, paratype), MF541642 (C-YN201107-11, paratype), MF541641 (C-YN201109-10, paratype), MF541644 (C-SCCZ2015003-04, paratype), MH 845520 (C-YN201720-01, paratype), MH 845485 (C-YN201735- 10, paratype), MH 845459 (C-YN201756-05, paratype), MH 845505 (C-YN201730-03, paratype), MH 845441 (C- YN201752 -01, paratype), MH 837684 (C- YN201606 -03, paratype). Remarks. A. rusticanus sp. nov. was collected from 10 sites in two provinces in southeast China: Yunnan Province (Xishuangbanna, Yuanjiang National Nature Reserve, Cangshan National Nature Reserve, Tongbiguan Provincial Nature Reserve, Nangunhe National Nature Reserve, Gaoligongshan National Nature Reserve, Yongde Daxueshan National Nature Reserve, and Jingdong Yi Autonomous County) and Sichuan Province (Mount Zhuji and Jinjiang County). The new species keys to the Amynthas hawayanus -group (Sims & Easton 1972). The hawayanus group is characterized by six thecal spermathecae in 5/6–7/8 and by holandry. To date, the group comprises 64 species (Nguyen et al. 2020b). Within the A. hawayanus -group, the morphological character of A. rusticanus sp. nov. can be described as “mediocre” because of its small body size, no representative and stable genital papillae outside, with simple style intestinal caeca and developed prostate glands. However, A. rusticanus sp. nov. has a relatively breadth geographical distribution in Southwest China, which recommend us to look for species with a wide geographical range as well as relatively similar morphology characters for comparison. Amynthas gracilis (Kinberg, 1867) is meeting our requirement. A. gracilis is a cosmopolitan species, and had been reported in 9 provinces in China, including eight spots in Southwest China (Xu & Xiao 2011). A. rusticanus sp. nov. has some similarities to the cosmopolitan species A. gracilis. Considering the polymorphic nature of the new species, several previously described morphs of A. gracilis were selected for comparison: the Sichuan morph described by Chen (1931), the Taiwan morph described by Chang et al. (2009 a), the Burma morph described by Gates (1972), and the US morph described by Blakemore (2009) and Chang et al. (2016). The present new species is similar to A. gracilis in the following characters: 1) pigmentation is present dorsally and absent ventrally, regardless of the preserving fluid used; 2) the clitellum may not always occupy the exact boundaries of XIV–XVI, instead failing to reach the boundaries or extending beyond; 3) there are three pairs of spermathecal pores in 5/6–7/8; 4) the intestinal caeca are simple; 5) the spermathecal diverticulum has a small, ovate seminal chamber and slender stalk, except in the case of the US morph specimens from the National Museum of Natural History, Smithsonian Institution, Washington, DC (Chang et al. 2016); 6) the prostate glands are developed. However, there are several differences: 1) the new species is smaller than all morphs of A. gracilis; 2) the first dorsal pore is found in 12/ 13 in the new species, whereas in A. gracilis it is found in 10/11 or 11/ 12 in the Taiwan morph and the US morph from the Smithsonian Institution, or 10/ 11 in the Sichuan morph, the Burma morph, and the US morph from Brookfield (Blakemore 2009); 3) there are no setae on the clitellum of the new species, but a few setae are always present on the ventral side of segment XVI in the Sichuan and Burma morphs of A. gracilis; 4) there are no genital markings in the spermathecal pore region of the new species, but they are present in A. gracilis in the Burma morph (segment VI-IX) and the US morph from Brookfield; 5) the male porophores are elevated and surrounded by 2-3 shallow skin folds in the new species, but the male pore is on top of a whorl-like elevation in the Sichuan morph of A. gracilis; 6) there are no genital papillae in the male pore region of the new species, but one or more medial and postsetal genital papillae are present in the Sichuan, Taiwan, Burma, and US morphs of A. gracilis; 7) the spermathecal duct is obviously longer than the ampulla in the new species, whereas it is shorter than the ampulla in the Taiwan, Burma, and US morphs of A. gracilis. On the other hand, Blakemore (2009) reported that the US morph of A. gracilis, in rare cases, has only two pairs of spermathecal pores; in this characteristic, it differs from the Sichuan morph, Taiwan morph, and Burma morph, but is similar to the new species. However, Chang et al. (2016) checked the specimens of A. gracilis preserved in the National Museum of Natural History, Smithsonian Institution, Washington, DC, and found that the US morph has three pairs of spermathecal pores. Considering the spermathecal pores (three pairs in 5/6–7/8), simple intestinal caeca and long spermathecal duct, A. rusticanus sp. nov. is also similar to the Chinese endemic species Amynthas limpidus (Chen, 1938). However, they still have several differences: 1) A. rusticanus (length 40–59 mm by width 1.9–2.0 mm) is smaller than A. limpidus (150 mm by 6.0 mm) in body size; 2) the setae are moderate (34–46 on III, 46–60 on V, 50–60 on VIII, 46–48 on XX, 44–50 on XXV) in number in the new species, but extremely numerous (82 on III, 128 on VI, 142 on VII, 96 on XXV) in A. limpidus; 3) there are no genital papillae in the spermathecal and male pore regions in the new species, but several genital markings are present in A. limpidus; 4) the prostate gland is developed in the new species, but undeveloped (Chen used “very small” to describe it) on A. limpidus; 5) the spermathecal diverticulum is shorter than the main spermathecal axis in the new species, but slightly longer than the main pouch in A. limpidus. Amynthas carnosus (Goto & Hatai, 1899) also keys to the A. hawayanus -group and is very common in Sichuan Province (Xu & Xiao 2011), but it is not morphologically similar to the new species in having big body size (vs. small body size as length 40–59 mm by width 1.9–2.0 mm), two pairs of genital papillae on spermathecal pore region (vs. no genital papillae on spermathecal pore region predominantly), three pairs of genital papillae on male pore region (vs. no genital papillae on male pore region), and spermathecal diverticulum straight as well as half as long as the main spermathecal axis (vs. spermathecal diverticulum shorter than the main spermathecal axis by ¼, its stalk straight or twisted into two zigzags, and distal ¼ dilated into a heart- or oval-shaped seminal chamber). Besides, we have given a comparison of genetic similarity (Table 2). The P-distance result (0.18) shows A. rusticanus sp. nov. and A. carnosus are different species.Published as part of Sun, Jing, Jiang, Ji-Bao, Wu, Juzhen, Yuan, Zhu & Qiu, Jiang-Ping, 2021, Three new widely distributed and polymorphic species of Amynthas earthworms (Oligochaeta, Clitellata, Megascolecidae) from South China, pp. 457-474 in Zootaxa 4938 (4) on pages 458-461, DOI: 10.11646/zootaxa.4938.4.5, http://zenodo.org/record/457494
Turbulence decay in a supersonic boundary layer subjected to a transverse sonic jet
No full textThe turbulence state in a supersonic boundary layer subjected to a transverse sonic jet is studied by conducting direct numerical simulations. Turbulence statistics for two jet-to-cross-flow momentum flux ratios of 2.3 and 5.5 based on the previous simulation (Sun & Hu, J. Fluid Mech., vol. 850, 2018, pp. 551-583) are given and compared with a flat-plate boundary layer without a jet. The instantaneous and time-averaged flow features around the transverse jet in the supersonic boundary layer are analysed. It is found that, in the near-wall region, turbulence is suppressed significantly with increasing in the lateral boundary layer around the jet and the turbulence decay is retained in the downstream recovery region. The local boundary-layer thickness decreases noticeably in the lateral downstream of the jet. Analysis of the cross-flow streamlines reveals a double-expansion character in the vicinity of the jet, which involves the reattachment expansion related to the flow over the jet windward separation bubble and the jet lateral expansion related to the flow around the jet barrel shock. The double expansion leads to the turbulence decay in the jet lateral boundary layer and causes a slow recovery of the outer layer in the far-field boundary layer. A preliminary experiment based on the nanoparticle laser scattering technique is conducted and confirms the existence of the turbulence decay phenomenon.</p
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