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Let X-center dot= (X, D-X) be a pointed stable curve of topological type (gX, nX) over an algebraically closed field of characteristic p > 0. Under certain assumptions, we prove that, if X-center dot is component-generic, then the...
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Let X-center dot= (X, D-X) be a pointed stable curve of topological type (gX, nX) over an algebraically closed field of characteristic p > 0. Under certain assumptions, we prove that, if X-center dot is component-generic, then the first generalized Hasse-Witt invariant of every prime-to- p cyclic admissible covering of X-center dot attains maximum. This result generalizes a result of S. Nakajima concerning the ordinariness of prime-to- p cyclic etale coverings of smooth projective generic curves to the case of (possibly ramified) admissible coverings of (possibly singular) pointed stable curves. Moreover, we prove that, if X-center dot is an arbitrary pointed stable curve, then there exists a prime-to-p cyclic admissible covering of X-center dot whose first generalized Hasse-Witt invariant attains maximum. This result generalizes a result ofM. Raynaud concerning the new-ordinariness of prime-top cyclic etale coverings of smooth projective curves to the case of (possibly ramified) admissible coverings of (possibly singular) pointed stable curves. As applications, we obtain an anabelian formula for (g(X), n(X)), and prove that the field structures associated to inertia subgroups of marked points can be reconstructed group-theoretically from open continuous homomorphisms of admissible fundamental groups. Those results generalize A. Tamagawa's results concerning an anabelian formula for topological types and reconstructions of field structures associated to inertia subgroups of marked points of smooth pointed stable curves to the case of arbitrary pointed stable curves.
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Clavicipitoid fungi comprise three families, namely Clavicipitaceae, Cordycipitaceae, and Ophiocordycipitaceae. They are found worldwide and are specialized pathogens of invertebrate, plant and fungal hosts. Over the last decade, ...
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Clavicipitoid fungi comprise three families, namely Clavicipitaceae, Cordycipitaceae, and Ophiocordycipitaceae. They are found worldwide and are specialized pathogens of invertebrate, plant and fungal hosts. Over the last decade, morphology- and phylogeny-based studies on clavicipitoid fungi have increased. The latter have revealed that Polycephalomyces, Perennicordyceps and Pleurocordyceps consistently cluster together. These genera are currently considered as members of Ophiocordycipitaceae. Nonetheless, information with regard to their diversity and ecology remains sparse. To fill this gap, we collected 29 fresh specimens from insect and fungal substrates from tropical and subtropical evergreen forests in Thailand and southwestern China. We performed detailed morphological analyses and constructed photoplates for all isolated fungi. We used extensive taxon sampling and a dataset comprising internal transcribed spacer gene region (ITS), small subunit ribosomal RNA gene region (SSU), large subunit rRNA gene region (LSU), translation elongation factor 1-alpha gene region (TEF-1 alpha), RNA polymerase II largest subunit gene region (RPB1) and RNA polymerase II second largest subunit (RPB2) to infer order-, family and genus-level phylogenetic trees. Based on these biphasic analyses, we segregate Polycephalomyces, Perennicordyceps, and Pleurocordyceps from Ophiocordycipitaceae and introduce the new family Polycephalomycetaceae to accomodate these three genera. The majority of species in this family have a vast range of insect and fungal hosts. The sexual morph of Polycephalomycetaceae has stromatic ascomata, long stipes, thick peridium, and cylindrical secondary spores. The asexual morph is characterized by colonies on the host surface or synnemata with stipes on the host, one or two types of phialides, and cylindrical to fusiform conidia. We expand the number of taxa in the new family by introducing seven new species (Polycephalomyces albiramus, Perennicordyceps lutea, Pleurocordyceps parvicapitata, Pleurocordyceps lanceolatus, Pleurocordyceps nutansis, Pleurocordyceps heilongtanensis, Pleurocordyceps vitellina), nine new hosts, and one new combination (Perennicordyceps elaphomyceticola). The results herein hint at a high level of diversity for Polycephalomycetaceae. Future investigations focusing on obtaining additional collections and specimens from different geographical areas would help to reveal not only the extent of the group's diversity, but also resolve its deeper phylogenetic placement.
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The supramolecular reactions of tetrabromoterephthalic acid (H-2-TBTA) with a series of N-heterocycles afforded eight new complexes, namely, [(H-2-BTAH)(2)center dot(TBTA)center dot(H-2-TBTA)] (1), [(H-2-Bim)(2)center dot(TBTA)cen...
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The supramolecular reactions of tetrabromoterephthalic acid (H-2-TBTA) with a series of N-heterocycles afforded eight new complexes, namely, [(H-2-BTAH)(2)center dot(TBTA)center dot(H-2-TBTA)] (1), [(H-2-Bim)(2)center dot(TBTA)center dot(H-2-TBTA)center dot 2H(2)O] (2), [(H-8-HQ)(2)center dot(TBTA)center dot 3H(2)O] (3), [(5-NO2-phen) 2 center dot(H-2-TBTA)] (4), [(4,6-DHP)(2)center dot(H-2-TBTA)center dot 2H(2)O] (5), [(H-2-2,4-DMI)(2)center dot(TBTA)center dot(H-2-TBTA)(2)] (6), [(H-2-3,5-DMP)(2)center dot(TBTA)] (7), and [(H-4-CNpy) 2 center dot(TBTA)center dot(H-2-TBTA)] (8) (H-BTAH = 1H-benzotriazole, H-Bim = 1H-benzimidazole, 8-HQ = 8-hydroxyquinoline, 5-NO2-phen = 5-nitro-1,10-phenanthroline, 4,6-DHP = 4,6-dihydroxypyrimidine, H-2,4-DMI = 2,4-dimethylimidazole, H-3,5-DMP = 3,5-dimethylpyrazole, and 4-CNpy = 4-cyanopyridine), which have been prepared under mild and identical reaction conditions in a mixture of distilled water and ethanol. All the complexes were fully characterized using single crystal X-ray diffraction analysis, elemental analysis, infrared spectroscopy (IR), and thermogravimetric analysis (TGA). Combining the various N-containing ligands and the diversity of the hydrogen bonds, the eight crystals display amusing structural characteristics. Among these complexes, complex 3 forms a three-dimensional (3D) network through the C-H center dot center dot center dot Br bonds, while the O-H center dot center dot center dot Br bonds facilitate the 3D construction of compound 2. Complexes 4-8 generate 3D supramolecular structures by utilizing a large number of hydrogen bonds. In crystal 1, the pi-pi stacking interactions play an important part in the 3D network. The thermal stability of crystals 1-8 has been investigated by thermogravimetric analysis (TGA) of mass loss.
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Tumor-infiltrating myeloid cells (TIMs) are key regulators in tumor progression, but the similarity and distinction of their fundamental properties across different tumors remain elusive. Here, by performing a pan-cancer analysis ...
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Tumor-infiltrating myeloid cells (TIMs) are key regulators in tumor progression, but the similarity and distinction of their fundamental properties across different tumors remain elusive. Here, by performing a pan-cancer analysis of single myeloid cells from 210 patients across 15 human cancer types, we identified distinct features of TIMs across cancer types. Mast cells in nasopharyngeal cancer were found to be associated with better prognosis and exhibited an anti-tumor phenotype with a high ratio of TNF+/VEGFA(+) cells. Systematic comparison between cDC1- and cDC2-derived LAMP3(+) cDCs revealed their differences in transcription factors and external stimulus. Additionally, pro-angiogenic tumor-associated macrophages (TAMs) were characterized with diverse markers across different cancer types, and the composition of TIMs appeared to be associated with certain features of somatic mutations and gene expressions. Our results provide a systematic view of the highly heterogeneous TIMs and suggest future avenues for rational, targeted immunotherapies.
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A dysfunctional immune response in coronavirus disease 2019 (COVID-19) patients is a recurrent theme impacting symptoms and mortality, yet a detailed understanding of pertinent immune cells is not complete. We applied single-cell ...
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A dysfunctional immune response in coronavirus disease 2019 (COVID-19) patients is a recurrent theme impacting symptoms and mortality, yet a detailed understanding of pertinent immune cells is not complete. We applied single-cell RNA sequencing to 284 samples from 196 COVID-19 patients and controls and created a comprehensive immune landscape with 1.46 million cells. The large dataset enabled us to identify that different peripheral immune subtype changes are associated with distinct clinical features, including age, sex, severity, and disease stages of COVID-19. Severe acute respiratory syndrome coronavirus 2 (SARSCoV-2) RNA was found in diverse epithelial and immune cell types, accompanied by dramatic transcriptomic changes within virus-positive cells. Systemic upregulation of S100A8/A9, mainly by megakaryocytes and monocytes in the peripheral blood, may contribute to the cytokine storms frequently observed in severe patients. Our data provide a rich resource for understanding the pathogenesis of and developing effective therapeutic strategies for COVID-19.
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The supercritical CO2 (sCO(2)) Brayton cycle has the advantages of high efficiency, good flexibility and compact equipment, and is widely regarded as the ideal power cycle for the new generation concentrating solar power (CSP). Th...
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The supercritical CO2 (sCO(2)) Brayton cycle has the advantages of high efficiency, good flexibility and compact equipment, and is widely regarded as the ideal power cycle for the new generation concentrating solar power (CSP). The application scenario of the CSP determines that the unit's fast peak shaving capability must be considered. In this paper, a dynamic simulation model was developed for an indirect-heated 800 degrees C/550 degrees C sCO(2) CSP test plant, containing a particle heat storage system. The effects of control modes of heating power, cooling power, mass flow rate (m), turbine rotational speed and sCO(2) inventory on the system dynamic characteristics were researched. It was found that the control mode of changing particle/water mass flow rate had a significantly faster response speed than changing temperature. Using the turbine optimal rotational speed control mode could improve the net cycle efficiency from 15.30% to 16.12%, in a continuous linear load reduction process. The sCO(2) inventory control module played a crucial role in limiting the fluctuation of compressor inlet pressure. The regulation mode of changing m and turbine inlet temperature (T-4) synchronously and that of changing m with constant T-4 were all proved to achieve the goal of fast peak shaving well, but the latter one was safer, which could greatly limit the temperature change rate of sCO(2) and equipment in the fast peak shaving process. Our work not only offers an operation solution for the sCO(2) CSP test plant, but also gives guidance for the efficient, flexible and safe design of the third generation CSP plants.
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Impact indentation is believed to be an effective indication of low-velocity impact (LVI) damage for polymer matrix composites. However, it has been discovered that an indentation can partially rebound over time. Impact indentatio...
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Impact indentation is believed to be an effective indication of low-velocity impact (LVI) damage for polymer matrix composites. However, it has been discovered that an indentation can partially rebound over time. Impact indentation and its rebound behavior over a period of time are significantly affected by hygrothermal conditions, especially moisture absorption. Therefore, a good understanding of the moisture-dependent impact indentation and its rebound behavior is helpful for impact damage assessment for composites. In this paper, moisture effects are considered for both the intra-laminar transverse property model and the interlaminar interface model in the simulation of impact indentation. Then, in these two models, viscosities are introduced to represent the indentation rebound over time. In order to validate the proposed models, LVI experiments with different impact energies were conducted on dry and hygrothermal conditioned carbon fiber/epoxy matrix composite laminates. For the specimens, the initial depths of impact dents and their rebounds over time were measured. The specimens of hygrothermal conditions were found with deeper dents compared with dry ones under the same impact energy; and their rebounds were also more significant. These phenomena were explained by the fact that moisture softens epoxy in composite and meanwhile elevates its viscosity. This indentation and its rebound phenomenon were simulated in ABAQUS by considering the moisture effects and viscoelasticity with user-defined material subroutines. These experiments were simulated using the proposed models, and the numerical predictions conformed well with the experimental observations.
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Let p be a prime number and k either a finite field of characteristic p or a generalized sub-p-adic field. Let X-1 and X-2 be hyperbolic curves over k. In the present paper, we introduce a kind of morphism between X-1 and X-2 call...
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Let p be a prime number and k either a finite field of characteristic p or a generalized sub-p-adic field. Let X-1 and X-2 be hyperbolic curves over k. In the present paper, we introduce a kind of morphism between X-1 and X-2 called an almost open immersion, and give some group-theoretic an almost open immersion, and give some group-theoretic characterizations for the set of almost open immersions between X-1 and X-2 via their arithmetic fundamental groups. This result generalizes the Isom-version of Grothendieck's anabelian conjecture for curves over k which has been proven by S. Mochizuki and A. Tamagawa to the case of almost open immersions. (C) 2019 Elsevier Inc. All rights reserved.
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This paper is concerned with a nonlocal within-host viral infection model with general incidence in a spatially heterogeneous environment. We first establish the well-posedness, boundedness and asymp-totic compactness of this mode...
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This paper is concerned with a nonlocal within-host viral infection model with general incidence in a spatially heterogeneous environment. We first establish the well-posedness, boundedness and asymp-totic compactness of this model. The basic reproduction number R0 is defined by using the perturbation technique. Then we study global stability of the infection-free steady state and show that the system is uniformly persistent when R0 > 1. In addition, for a special incidence function, the existence, uniqueness and global stability of the infection steady state of this model are established. Finally, we present some examples and numerical simulations to illustrate the obtained results.
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Let (X, D-X) be a smooth pointed stable curve over an algebraically closed field kof characteristic p > 0. Suppose that (X, D-X) is generic. We give a necessary and sufficient condition for new-ordinariness of prime-to-pcyclic tam...
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Let (X, D-X) be a smooth pointed stable curve over an algebraically closed field kof characteristic p > 0. Suppose that (X, D-X) is generic. We give a necessary and sufficient condition for new-ordinariness of prime-to-pcyclic tame coverings of (X, D-X). This result generalizes a result of S. Nakajima concerning the ordinariness of prime-to-p cyclic etale coverings of generic curves to the case of tamely ramified coverings. (C) 2021 Elsevier Inc. All rights reserved.
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