224,979 research outputs found
New source for L-iditol and taxanes
Get PDFWe describe the first report of the recovery of L-iditol and Taxane from an angiosperm- Yunnanopilia longistaminata (W.Z.Li) C.Y.Wu et D.Z.Li (Opiliaceae). Two taxane compounds and L-iditol were isolated from the tender burgeon of Yunnanopilia longistaminata, and their structure were identified as Taxayunnansin B, Taxumairol E and L-iditol on the basis of NMR and MS spectrum, respectively. It is a new plant source for L-iditol and taxanes
Facile syntheses of l-beta-haloalanine derivatives from l-cysteine or l-cystine
No full textl-beta-Haloalanines are physiologically active unnatural amino acids and they are useful intermediates for the synthesis of natural and unnatural amino acids, S-linked glycopeptides, and lanthionines. In general l-beta-haloalanines were prepared predominantly from l-serine via functional group transformation. Here we reported an alternative approach for the preparation of l-beta-haloalanines via halogenation of protected l-cysteine esters which was obtained from l-cysteine or l-cystine, respectively. The mercapto group of protected l-cysteine esters was efficiently transformed to halo groups by triphenylphosphine/N-halosuccinimides. It has been proved to be a versatile desulfurization strategy via this functional group transformation
Bp. François Liu (Liou) l
No full textBp. François Liu (Liou) l 劉錦方, Vicar apostolic of Fenyang 汾陽.https://digitalcommons.whitworth.edu/album07/1141/thumbnail.jp
Bp. François Liu (Liou) l
No full textAutographed picture given to Fr. Paul Gilson. Bp. François Liu (Liou) l 劉錦方, Vicar apostolic of Fenyang 汾陽.https://digitalcommons.whitworth.edu/album07/1171/thumbnail.jp
Effects of Rate Adaption on the Throughput of Random Ad Hoc Networks
No full textThe capacity of wireless ad hoc networks has been studied in an excellent treatise by Gupta and Kumar [1], assuming a fixed transmission rate. By contrast, in this treatise we investigate the achievable throughput improvement of rate adaptation in the context of random ad hoc networks, which have been studied in conjunction with a fixed transmission rate in [1]. Our analysis shows that rate adaptation has the potential of improving the achievable throughput compared to fixed rate transmission, since rate adaptation mitigates the effects of link quality fluctuations. However, even perfect rate control fails to change the scaling law of the per-node throughput result given in [1], regardless of the absence or presence of shadow fading. This result is confirmed in the context of specific adaptive modulation aided design examples
Gautieria mianjin Kun L. Yang, Xiao Liu & Zhu L. Yang 2023, sp. nov.
No full textGautieria mianjin Kun L. Yang, Xiao Liu & Zhu L. Yang, sp. nov. (Figs. 1 and 2) Mycobank No.: MB847194 Etymology: —The epithet refers to a kind of traditional Chinese food, named “mianjin”. Mianjin is made from gluten, irregularly subglobose and honeycomb-like in shape, and has a thin film on surface present when raw, easily broken when cooked, sharing a strong resemblance to the basidioma of this fungus. Diagnosis: — Gautieria mianjin is similar and close to G. xinjianensis, but differs from the latter by its subglobose to broadly ellipsoid basidiospores mainly measured 11–14×10–12 μm with 10–14 longitudinal ribs. Type: — China, Gansu Province, Gannan Tibetan Autonomous Prefecture, Lintan County, Yeliguan Town, 34°55′ N, 103°39′ E, on soil in temperate forests dominated by plants of Larix and Picea, altitude 2600 m, October 11, 2022, Xiao Liu 001 (HKAS126926, holotype!; Kun-Long Yang’s private herbarium HTBM0250, isotype!). Basidioma with pleasant aroma, emergent, irregularly subglobose, 2.5–5 cm in diameter. Peridium practically absent. Gleba brain-like to honeycomb-like; tramal plates 400–500 μm thick, milky white (C 4 M 3 Y 2 K 0), slightly gelatinous, covered with sandy yellow (C 0 M 10 Y 50 K 10), earthy yellow (C 10 M 40 Y 70 K 10) to mummy brown (C 0 M 50 Y 70 K 40) spore mass; columella indistinct, very slender and sometimes the same thick as the tramal plates, emanating from the base and frequently branching; locules irregularly shaped, labyrinthine. Basal rhizomorph whitish (C 0 M 1 Y 5 K 0). Basidiospores subglobose to broadly ellipsoid, light brown (C 30 M 40 Y 60 K 0) in KOH, with 10–14 longitudinal ribs, sometimes branching or with cross veins in between, (10) 11–14 (16) [12.24 ± 1.20] × (9.5) 10–12 (13) [10.96 ± 0.77] μm, Q = (1.00) 1.04–1.24 (1.26) and Q m = 1.12 ± 0.07 including ribs, (9) 10–12 (15) [11.53 ± 1.36] × (8) 9–10 (11) [9.33 ± 0.69] μm, Q = (1.05) 1.15–1.33 (1.43) and Q m = 1.23 ± 0.10 excluding ribs; apiculus 1–2 (2.5) [1.88 ± 0.42] × 1.5–2 [1.92 ± 0.24] μm. Basidia not observed. Cystidia not observed. Tramal hyphae composed of 2–8 μm wide interwoven filamentous hyphae, frequently branching, not or slightly gelatinized. Clamps absent in all parts of basidioma. Habitat: —Growing in small groups on soil in temperate forests dominated by trees of Larix and Picea. Currently known from northwestern China (Gansu Province, and probably also Xinjiang Uygur Autonomous Region according to the ITS sequence of “Uncultured fungus” (Fig. 1) in Du et al. 2019).Published as part of Yang, Kun L., Yang, Zhu L., Zhang, Ming, Wang, Geng-Shen & Liu, Xiao, 2023, Gautieria mianjin (Gomphales, Basidiomycota), a new species of false truffle from China, pp. 119-129 in Phytotaxa 594 (2) on page 123, DOI: 10.11646/phytotaxa.594.2.3, http://zenodo.org/record/789236
A Subband-Selective Broadband GSC with Cosine-Modulated Blocking Matrix
Get PDFIn this paper, a novel subband-selective generalized sidelobe canceller (GSC) for partially adaptive broadband beamforming is proposed. The columns of the blocking matrix are derived from a prototype vector by cosine-modulation, and the broadside constraint is incorporated by imposing zeros on the prototype vector appropriately. These columns constitute a series of bandpass filters, which select signals with specific angles of arrival and frequencies. This results in highpass-type bandlimited spectra of the blocking matrix outputs, which is further exploited by subbands decomposition and suitably discarding the low-pass subbands prior to running independent unconstrained adaptive filters in each non-redundant subband. By these steps, the computational complexity of a GSC implementation is greatly reduced compared to fully adaptive GSC schemes, while performance is comparable or even enhanced due to subband decorrelation in both spatial and temporal domains
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