No abstract

No abstract

BackgroundAnaplasmosis is caused by obligate intracellular bacteria in the genus Anaplasma. These bacterial pathogens are transmitted by ticks and impact both human and animal health. This study was conducted to determine the prevalence and molecular characterization of Anaplasma spp. in ruminants sampled in Xinjiang, northwest China.MethodsA survey was performed in August 2012 in rural areas of six counties in Xinjiang province. A total of 250 blood samples from ruminants were collected and tested for the presence of Anaplasma spp. by PCR. Positive samples were genetically characterized based on the 16S rRNA and msp4 genes.ResultsThe results showed a high prevalence of Anaplasma spp. in ruminants, with at least three different Anaplasma species detected (A. phagocytophilum, A. bovis and A. ovis). The mean prevalence of single infection with each species was 17.6% (A. phagocytophilum), 4.8% (A. bovis) and 40.5% (A. ovis). Coinfection occurred in 20 (8.0%) animals. Phylogenetic analysis of the 16S rRNA gene of A. bovis and A. phagocytophilum revealed a higher degree of genetic diversity for the latter. The results for A. ovis showed genotypic variation among geographic regions in China. In addition, a closely related isolate to the canine pathogen A. platys was identified in ruminants.ConclusionsThis survey revealed a high prevalence of Anaplasma sp. infections in sheep and cattle in the northwestern border regions of China, indicating the potential risk of transboundary disease.

Ag-hollandite nanofibers were synthesized through a simple hydrothermal process by oxidizing Mn(NO 3 ) 2 with AgMnO 4 in aqueous solution. The temperature was found to play an essential role in determining both the crystalline structure and the morphology of the Ag-hollandite materials, whereas the AgMnO 4 /Mn(NO 3 ) 2 molar ratio affected only the morphology of the product. Ag-hollandite nanofibers with diameters of 20-40 nm and lengths of 0.5-4 µm were prepared at 160 °C and a 2/3 AgMnO 4 / Mn(NO 3 ) 2 molar ratio. X-ray photoelectron spectroscopy surface analysis revealed that the silver species presented as Ag + and the average oxidation state of manganese was 3.9. More promisingly, the Aghollandite nanofibers showed quite high catalytic performance for ethanol oxidation, with ethanol conversion of 75% and acetaldehyde selectivity of 95% at 230 °C for 200 h time-on-stream. The high activity, selectivity, and stability were attributed to the stable presence of Ag + species and the unique morphology of the Ag-hollandite nanofibers.

Dimethyl ether (DME) carbonylation to methyl acetate (MA) was comparatively investigated over HZSM-35 and mordenite (HMOR) zeolites. The HZSM-35 catalyst showed rather high selectivity and stability without obvious deactivation for 32 h on-stream at 473 K with a MA yield of *11%. On the other hand, the HMOR catalyst showed similar initial activity, but the yield of MA rapidly decreased to only 5% after 20 h on-stream. It was further revealed that the deposition rate of coke over the HZSM-35 catalyst was much lower than that on the HMOR zeolite, indicating that the formation rate of coke was strongly dependent on the pore sizes of the zeolites. The pore structure of HZSM-35 having a one-dimensional channel 10 member-ring (10-MR) and a perpendicularly intersected one-dimensional 8 member-ring (8-MR) channel effectively limited the formation of aromatic compounds which act as the precursors of coke.

Background Anaplasma spp. are tick-transmitted bacteria that infect a wide variety of wild and domestic animals. These pathogens exhibit a high degree of biological diversity, broad geographical distribution, and represent a serious threat to veterinary and public health worldwide.ResultsA novel Anaplasma species was identified in Haemaphysalis qinghaiensis (Ixodidae) in northwestern China and was molecularly characterized by comparison of 16S rRNA, gltA, and groEL gene sequences. Of the 414 samples tested, 24 (5.8%) were positive for this Anaplasma species. On the basis of the 16S rRNA gene, this organism has been found to be closely related to and exhibit the highest sequence similarity with A. capra (99.8–99.9%) that was identified in goats and humans in northern China, but was distinct from other known Anaplasma species. Sequence analysis of the gltA and groEL genes revealed that this Anaplasma species was distinct from A. capra considering the lower sequence identity (88.6–88.7% for gltA and 90.6–91.0% for groEL) and a divergent phylogenetic position. Therefore, we described this Anaplasma species as A. capra-like bacteria.ConclusionsThe present study reports a potential novel Anaplasma species closely related to A. capra in H. qinghaiensis in northwestern China. The zoonotic potential of A. capra-like bacteria needs to be further determined.

No abstract

Methanol selective oxidation to methyl formate was investigated over ReO x /CeO 2 catalysts in terms of Re loading and reaction mechanism. It was found that Re loading with monolayer dispersion on ceria exhibited promising reaction rate of methanol of 16 mmol g cat.-1 h -1 and methyl formate selectivity of about 90% at 513 K. The surface reaction of methanol, formaldehyde, and methyl formate over the ReO x /CeO 2 catalyst was investigated by in situ Fourier transform infrared spectroscopy and it was revealed that the formate species, formed by the oxidation of adsorbed -OCH 3 species, could act as the key reaction intermediate, which further reacted with gaseous methanol to form methyl formate and/or decompose into CO and CO 2 , depending on the reaction temperature.