181 research outputs found
'Cand. Actinochlamydia clariae' gen. nov., sp. nov., a Unique Intracellular Bacterium Causing Epitheliocystis in Catfish (Clarias gariepinus) in Uganda
Background and Objectives: Epitheliocystis, caused by bacteria infecting gill epithelial cells in fish, is common among a large range of fish species in both fresh-and seawater. The aquaculture industry considers epitheliocystis an important problem. It affects the welfare of the fish and the resulting gill disease may lead to mortalities. In a culture facility in Kampala, Uganda, juveniles of the African sharptooth catfish (Clarias gariepinus) was observed swimming in the surface, sometimes belly up, showing signs of respiratory problems. Histological examination of gill tissues from this fish revealed large amounts of epitheliocysts, and also presence of a few Ichthyobodo sp. and Trichodina sp.
Methods and Results: Sequencing of the epitheliocystis bacterium 16S rRNA gene shows 86.3% similarity with Candidatus Piscichlamydia salmonis causing epitheliocystis in Atlantic salmon (Salmo salar). Transmission electron microscopy showed that the morphology of the developmental stages of the bacterium is similar to that of members of the family Chlamydiaceae. The similarity of the bacterium rRNA gene sequences compared with other chlamydia-like bacteria ranged between 80.5% and 86.3%. Inclusions containing this new bacterium have tubules/channels (termed actinae) that are radiating from the inclusion membrane and opening on the cell surface or in neighbouring cells.
Conclusions: Radiation of tubules/channels (actinae) from the inclusion membrane has never been described in any of the other members of Chlamydiales. It seems to be a completely new character and an apomorphy. We propose the name Candidatus Actinochlamydia clariae gen. nov., sp. nov. (Actinochlamydiaceae fam. nov., order Chlamydiales, phylum Chlamydiae) for this new agent causing epitheliocystis in African sharptooth catfish
Manipulation of room-temperature valley-coherent exciton-polaritons in atomically thin crystals by real and artificial magnetic fields
The WĂŒrzburg group acknowledges support by the state of Bavaria. C.S. acknowledges support by the European Research Commission (Project unLiMIt-2D). This work has been supported by the Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. F.E gratefully acknowledge the financial support by the German Federal Ministry of Education and Research via the funding â2D Nanomaterialien fĂŒr die Nanoskopie der Zukunftâ. Work of E.S. and A.K. was supported by foundation of Westlake University (Project No. 041020100118 ). E.S. acknowledges partial support from the Grant of the President of the Russian Federation for state support of young Russian scientists No. MK-2839.2019.2. A.K. acknowledges the Saint-Petersburg State University for the research grant ID 40847559. SK.W and T.T. acknowledge support from the Elemental Strategy Initiative conducted by the MEXT, Japan and the CREST (JPMJCR15F3), JST. S.T. acknowledges support by the NSF (DMR-1955668 and DMR-1838443). H.K. is supported via the Max Planck School of Photonics.Strong spin-orbit coupling and inversion symmetry breaking in transition metal dichalcogenide monolayers yield the intriguing effects of valley-dependent optical selection rules. As such, it is possible to substantially polarize valley excitons with chiral light and furthermore create coherent superpositions of K and Kâ polarized states. Yet, at ambient conditions dephasing usually becomes too dominant, and valley coherence typically is not observable. Here, we demonstrate that valley coherence is, however, clearly observable for a single monolayer of WSe2, if it is strongly coupled to the optical mode of a high quality factor microcavity. The azimuthal vector, representing the phase of the valley coherent superposition, can be directly manipulated by applying magnetic fields, and furthermore, it sensibly reacts to the polarization anisotropy of the cavity which represents an artificial magnetic field. Our results are in qualitative and quantitative agreement with our model based on pseudospin rate equations, accounting for both effects of real and pseudo-magnetic fields.PostprintPeer reviewe
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Green pigments are formed by mixing chlorogenic acid(Chl) and glycine under the alkaline condition. The analysis of the green solution by RP (Reversed Phase)-HPLC under the alkaline condition with a multi-channel detector revealed that the reaction products were composed of several components.On the other hand, the RP-HPLC pattern of the sample under the acidic condition indicated 2 peaks other than that of Chl. Surprisingly, molecular weight of each substance was determined by LC-MS analysis to be 355, which corresponds to the molecular weight for protonated ion of Chl. These findings suggest that the change of pH condition may result in the formation of Chl isomers
A global database of dissolved organic matter (DOM) concentration measurements in coastal waters (CoastDOM v1)
Measurements of dissolved organic carbon (DOC), nitrogen (DON), and phosphorus (DOP) con-centrations are used to characterize the dissolved organic matter (DOM) pool and are important components ofbiogeochemical cycling in the coastal ocean. Here, we present the first edition of a global database (CoastDOMv1; available at https://doi.org/10.1594/PANGAEA.964012, L\uf8nborg et al., 2023) compiling previously pub-lished and unpublished measurements of DOC, DON, and DOP in coastal waters. These data are complementedby hydrographic data such as temperature and salinity and, to the extent possible, other biogeochemical variables(e.g. chlorophyll a, inorganic nutrients) and the inorganic carbon system (e.g. dissolved inorganic carbon andtotal alkalinity). Overall, CoastDOM v1 includes observations of concentrations from all continents. However,most data were collected in the Northern Hemisphere, with a clear gap in DOM measurements from the SouthernHemisphere. The data included were collected from 1978 to 2022 and consist of 62 338 data points for DOC,20 356 for DON, and 13 533 for DOP. The number of measurements decreases progressively in the sequenceDOC > DON > DOP, reflecting both differences in the maturity of the analytical methods and the greater focuson carbon cycling by the aquatic science community. The global database shows that the average DOC concen-tration in coastal waters (average \ub1 standard deviation (SD): 182 \ub1 314 ÎŒmol C Lâ1; median: 103 ÎŒmol C Lâ1) is13-fold higher than the average coastal DON concentration (13.6 \ub1 30.4 ÎŒmol N Lâ1; median: 8.0 ÎŒmol N Lâ1),which is itself 39-fold higher than the average coastal DOP concentration (0.34 \ub1 1.11 ÎŒmol P Lâ1; median:0.18 ÎŒmol P Lâ1). This dataset will be useful for identifying global spatial and temporal patterns in DOM and willhelp facilitate the reuse of DOC, DON, and DOP data in studies aimed at better characterizing local biogeochem-ical processes; closing nutrient budgets; estimating carbon, nitrogen, and phosphorous pools; and establishing abaseline for modelling future changes in coastal waters
Properties of Îł-decaying isomers in the Sn 100 region populated in fragmentation of a Xe 124 beam
A systematic study was performed of microsecond Îł-decaying isomers around Sn100 produced in a fragmentation reaction of a Xe124 beam at 345 MeV/u at the Radioactive Ion Beam Factory of the RIKEN Nishina Center in Saitama, Japan. Half-lives of isomeric states in that region were remeasured allowing us to improve the currently available experimental information. Reduced transition probabilities were deduced and compared to shell-model calculations in various model spaces. The recently reported low-energy transitions in Rh92 and Ag96 were remeasured with improved precision. Additionally, experimental information on isomeric ratios, including five new ones, were extracted and compared to a previous experimental study and the sharp cutoff model of fragmentation reaction
An improved method to represent DEM uncertainty in glacial lake outburst flood propagation using stochastic simulations
ChemInform Abstract: Copper Mediated Defluorinative Allylic Alkylation of Difluorohomoallyl Alcohol Derivatives Directed to an Efficient Synthetic Method for (Z)-Fluoroalkene Dipeptide Isosteres.
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