1,060 research outputs found

    Tetra-O-4-methyl­phenyl­sulfonyl­penta­erythritol

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    In the title mol­ecule (systematic name: methane­tetra­yltetra­methyl­ene tetra-p-toluene­sulfonate), C33H36O12S4, the central C atom and the S atoms exhibit distorted tetra­hedral configurations. The aromatic rings in opposite arms are nearly parallel to each other, with a dihedral angle of 10.26 (8) or 3.45 (9)°. The mol­ecules are linked into a two-dimensional network parallel to the bc plane by weak C—H⋯O hydrogen bonds, π–π [centroid–centroid distance = 3.5806 (12) Å] and S—O⋯π [O⋯centroid = 3.1455 (15) Å and S—O⋯centroid = 122.41 (7)°] inter­molecular inter­actions. Intramolecular C—H⋯O hydrogen bonds are also present

    Uplift, Climate and Biotic Changes at the Eocene-Oligocene Transition in Southeast Tibet

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    The uplift history of southeastern Tibet is crucial to understanding processes driving the tectonic evolution of the Tibetan Plateau and surrounding areas. Underpinning existing palaeoaltimetric studies has been regional mapping based in large part on biostratigraphy that assumes a Neogene modernisation of the highly diverse, but threatened, Asian biota. Here, with new radiometric dating and newly-collected plant fossil archives, we quantify the surface height of part of Tibet’s southeastern margin of Tibet in the latest Eocene (~34 Ma) to be ~3 km and rising, possibly attaining its present elevation (3.9 km) in the early Oligocene. We also find that the Eocene-Oligocene transition in southeastern Tibet witnessed leaf size diminution and a floral composition change from sub-tropical/warm temperate to cool temperate, likely reflective of both uplift and secular climate change, and that by the latest Eocene floral modernization on Tibet had already taken place implying modernization was deeply-rooted in the Paleogene

    Zinc-blende and wurtzite GaAs quantum dots in nanowires studied using hydrostatic pressure

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    We report both zinc-blende (ZB) and wurtzite (WZ) crystal phase self-assembled GaAs quantum dots (QDs) embedding in a single GaAs/AlGaAs core-shell nanowires (NWs). Optical transitions and single-photon characteristics of both kinds of QDs have been investigated by measuring photoluminescence (PL) and time-resolved PL spectra upon application of hydrostatic pressure. We find that the ZB QDs are of direct band gap transition with short recombination lifetime (~1 ns) and higher pressure coefficient (75-100 meV/GPa). On the contrary, the WZ QDs undergo a direct-to-pseudodirect bandgap transition as a result of quantum confinement effect, with remarkably longer exciton lifetime (4.5-74.5 ns) and smaller pressure coefficient (28-53 meV/GPa). These fundamentally physical properties are further examined by performing state-of-the-art atomistic pseudopotential calculations

    Streptomyces sparsus, sp. nov., a novel member of the genus Streptomyces from saline and alkaline soil in China

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    Salt and alkaline-tolerant actinomycete strain, YIM 90018T, was isolated from a saline and alkaline soil sample collected from Qinghai, China, and was then subjected to polyphasic taxonomy. Aerial hyphae of strain YIM 90018T were not produced on almost tested media except YIM 82# agar. Vegetative hyphae were abundant, developed well, and not fragmented. Straight or flexuous (Rectiflexibiles) spore chains. The strain grew well at 25% of MgCl2.6H2O and pH 10. All of these characters consistently assign the strain YIM 90018T to known species of the genus Streptomyces. Based on phylogenetic analysis of 16S rDNA, DNA-DNA hybridization, phenotypic characters and comparison with known species of the genus, strain YIM 90018T can be differentiated from all the validly described Streptomyces species. A novel species, Streptomyces sparsus sp. nov. is proposed. The type strain of the new species is YIM 90018T (CCTCC AA204019= DSM 41858T)

    Probing two driven double quantum dots strongly coupled to a cavity

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    We experimentally and theoretically study a driven hybrid circuit quantum electrodynamics (cQED) system beyond the dispersive coupling regime. Treating the cavity as part of the driven system, we develop a theory applicable to such strongly coupled and to multi-qubit systems. The fringes measured for a single driven double quantum dot (DQD)-cavity setting and the enlarged splittings of the hybrid Floquet states in the presence of a second DQD are well reproduced with our model. This opens a path to study Floquet states of multi-qubit systems with arbitrarily strong coupling and reveals a new perspective for understanding strongly driven hybrid systems.Comment: 9 pages, 6 figure

    Streptomyces hainanensis sp nov., a novel member of the genus Streptomyces

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    A novel isolate belonging to the genus Streptomyces, strain YIM 47672(T), was obtained from soil from Hainan, an island in China. The characterization of this isolate was performed by using a polyphasic approach. The strain formed long spore chains in the aerial mycelia. The cell wall contained L-diaminopimelic acid, traces of meso-diaminopimelic acid and glycine. Whole-cell hydrolysates contained galactose and xylose. The phospholipid was of type II. The 16S rRNA gene sequence similarities for YIM 47672(T) with respect to the most closely related type strains of species of the genus Streptomyces were less than 96.3%. Therefore strain YIM 47672(T) represents a novel member of the genus Streptomyces, for which the name Streptomyces hainanensis sp. nov. is proposed. The type strain is YIM 47672 (T) (=CCTCC AA 205017(T) = DSM 41 900(T))

    Emerging tick-borne infections in mainland China: an increasing public health threat

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    Since the beginning of the 1980s, 33 emerging tick-borne agents have been identified in mainland China, including eight species of spotted fever group rickettsiae, seven species in the family Anaplasmataceae, six genospecies in the complex Borrelia burgdorferi sensu lato, 11 species of Babesia, and the virus causing severe fever with thrombocytopenia syndrome. In this Review we have mapped the geographical distributions of human cases of infection. 15 of the 33 emerging tick-borne agents have been reported to cause human disease, and their clinical characteristics have been described. The non-specific clinical manifestations caused by tick-borne pathogens present a major diagnostic challenge and most physicians are unfamiliar with the many tick-borne diseases that present with non-specific symptoms in the early stages of the illness. Advances in and application of modern molecular techniques should help with identification of emerging tick-borne pathogens and improve laboratory diagnosis of human infections. We expect that more novel tick-borne infections in ticks and animals will be identified and additional emerging tick-borne diseases in human beings will be discovered

    Yersinia pseudotuberculosis Exploits CD209 Receptors for Promoting Host Dissemination and Infection

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    Yersinia pseudotuberculosis is a Gram-negative enteropathogen and causes gastrointestinal infections. It disseminates from gut to mesenteric lymph nodes (MLNs), spleen, and liver of infected humans and animals. Although the molecular mechanisms for dissemination and infection are unclear, many Gram-negative enteropathogens presumably invade the small intestine via Peyer's patches to initiate dissemination. In this study, we demonstrate that Y. pseudotuberculosis utilizes its lipopolysaccharide (LPS) core to interact with CD209 receptors, leading to invasion of human dendritic cells (DCs) and murine macrophages. These Y. pseudotuberculosis CD209 interactions result in bacterial dissemination to MLNs, spleens, and livers of both wild-type and Peyer's patch-deficient mice. The blocking of the Y. pseudotuberculosis CD209 interactions by expression of 0-antigen and with oligosaccharides reduces infectivity. Based on the well-documented studies in which HIV-CD209 interaction leads to viral dissemination, we therefore propose an infection route for Y. pseudotuberculosis where this pathogen, after penetrating the intestinal mucosal membrane, hijacks the Y. pseudotuberculosis CD209 interaction antigen-presenting cells to reach their target destinations, MLNs, spleens, and livers.Peer reviewe

    Towards a global One Health index: a potential assessment tool for One Health performance

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    BACKGROUND: A One Health approach has been increasingly mainstreamed by the international community, as it provides for holistic thinking in recognizing the close links and inter-dependence of the health of humans, animals and the environment. However, the dearth of real-world evidence has hampered application of a One Health approach in shaping policies and practice. This study proposes the development of a potential evaluation tool for One Health performance, in order to contribute to the scientific measurement of One Health approach and the identification of gaps where One Health capacity building is most urgently needed. METHODS: We describe five steps towards a global One Health index (GOHI), including (i) framework formulation; (ii) indicator selection; (iii) database building; (iv) weight determination; and (v) GOHI scores calculation. A cell-like framework for GOHI is proposed, which comprises an external drivers index (EDI), an intrinsic drivers index (IDI) and a core drivers index (CDI). We construct the indicator scheme for GOHI based on this framework after multiple rounds of panel discussions with our expert advisory committee. A fuzzy analytical hierarchy process is adopted to determine the weights for each of the indicators. RESULTS: The weighted indicator scheme of GOHI comprises three first-level indicators, 13 second-level indicators, and 57 third-level indicators. According to the pilot analysis based on the data from more than 200 countries/territories the GOHI scores overall are far from ideal (the highest score of 65.0 out of a maximum score of 100), and we found considerable variations among different countries/territories (31.8–65.0). The results from the pilot analysis are consistent with the results from a literature review, which suggests that a GOHI as a potential tool for the assessment of One Health performance might be feasible. CONCLUSIONS: GOHI—subject to rigorous validation—would represent the world’s first evaluation tool that constructs the conceptual framework from a holistic perspective of One Health. Future application of GOHI might promote a common understanding of a strong One Health approach and provide reference for promoting effective measures to strengthen One Health capacity building. With further adaptations under various scenarios, GOHI, along with its technical protocols and databases, will be updated regularly to address current technical limitations, and capture new knowledge. GRAPHICAL ABSTRACT: [Image: see text] SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s40249-022-00979-9
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