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A loop-mediated isothermal amplification (LAMP) technique has been widely used in detecting the nucleic acid of various pathogenic bacteria. In this study, a set of four LAMP primers was designed to specifically test Anaplasma bovis. The LAMP assay was performed at 62°C for 60min in a water bath. The specificity was confirmed by amplifying A. bovis isolate, while no cross reaction was observed with other five pathogens (Anaplasma bovis, Anaplasma phagocytophilum, Theileria luwenshuni, Babesia motasi and Schistosoma japonicum). The sensitivity of LAMP was 5×100copies/μL, 100 times more than that of conventional PCR (5×102copies/μL). Of 120 blood DNA extracted from sheep and goats field samples, 81 (67.5%), 22 (18.3%) and 43 (35.8%) were positively detected by LAMP, conventional PCR and nested PCR, respectively. The findings indicated that the developed LAMP assay is a new convenient tool for rapid and cost-effective detection of A. bovis.

Background Hemotropic mycoplasmas (hemoplasmas) are emerging zoonotic pathogens with a worldwide distribution that can cause mild to severe hemolytic anemia, icterus, ill-thrift, infertility, and poor weight gain. However, understanding of the molecular epidemiology of hemoplasmas (Mycoplasma ovis and ‘Candidatus Mycoplasma haemovis’) is limited in sheep and goats, and the hemoplasma strain/species/variant ‘Candidatus M. haemovis’ was poorly studied throughout the world and had never been detected in China until now. Thus, the aim of the present study was to determine the molecular prevalence of hemoplasmas, including M. ovis and ‘Candidatus M. haemovis’ in sheep and goats from seven provinces and one autonomous region of China. Methods A total of 1364 blood samples were collected from sheep and goats in seven provinces and one autonomous region of China. All blood samples were tested for hemoplasmas (M. ovis and ‘Candidatus M. haemovis’) by nested PCR amplification based on 16S rRNA gene. Positive specimens underwent nucleotide sequencing and phylogenetic analysis. Results Overall, 610 specimens (44.7%, 610/1364) were shown to be hemoplasmas (M. ovis and ‘Candidatus M. haemovis’) -positive by nested PCR amplification based on 16S rRNA gene. The prevalence in goats was 44.1% (379/860), and 45.8% (231/504) in sheep, while that in grazing small ruminants was 54.4% (396/728) and 33.6% (214/636) in house feeding small ruminants. Sequencing of the nearly complete 16S rRNA gene was successful for the 103 randomly selected positive specimens from different farms in different sampling sites of China. Among them, analysis of the 16S rRNA gene sequences identified M. ovis (n = 56) and ‘Candidatus M. haemovis’ (n = 47). Two (KU983740 and KU983746) of the four novel genotypes obtained in this study were closely related to M. ovis, while the other two genotypes (KU983748 and KU983749) had high identity with ‘Candidatus M. haemovis’. Remarkably, the genotype (KU983740) of M. ovis in sheep and goats in this study fell in a clade with two human hemoplasmas from USA (KF313922 and GU230144) and shared 99.8%–99.9% with them. Conclusions In this study, ‘Candidatus M. haemovis’ was first detected in Chinese sheep and goats and hemoplasmas (M. ovis and ‘Candidatus M. haemovis’) are highly prevalent, and widely distributed in China. Electronic supplementary material The online version of this article (doi:10.1186/s12917-017-1062-z) contains supplementary material, which is available to authorized users.

In this paper, the grouping aggaregation problem of multi-robot in simple environment is studied. The grouping algorithm and aggregation algorithm are mainly discussed. Based on K-means clustering algorithm, a grouping control algorithm that can determine the number of groups and complete the grouping task autonomously was designed. Aiming at the problem of aggregation, three kinds of aggregation algorithms are proposed. Taking the center aggregation control as an example, the cooperation and control of each group of robots are studied. Finally, the simulation results of MATLAB show that the multi-robot grouping and aggregation algorithm is effective.

Simian foamy viruses (SFV) are complex retroviruses that are ubiquitous in nonhuman primates (NHP) and are zoonotically transmitted to humans, presumably through NHP saliva, by licking, biting, and other behaviors. We have studied SFV in free-ranging rhesus macaques in Bangladesh. It has been previously shown that SFV in immunocompetent animals replicates to detectable levels only in superficial epithelial cells of the oral mucosa, although latent proviruses are found in most, if not all, tissues. In this study, we compare DNA sequences from latent SFV proviruses found in blood cells of 30 Bangladesh rhesus macaques to RNA sequences of transcriptionally active SFV from buccal swabs obtained from the same animals. Viral strains, defined by differences in SFV gag sequences, from buccal mucosal specimens overlapped with those from blood samples in 90% of animals. Thus, latent proviruses in peripheral blood mononuclear cells (PBMC) are, to a great extent, representative of viruses likely to be transmitted to other hosts. The level of SFV RNA in buccal swabs varied greatly between macaques, with increasing amounts of viral RNA in older animals. Evidence of APOBEC3-induced mutations was found in gag sequences derived from the blood and oral mucosa.

Simian foamy viruses (SVF) are ubiquitous in nonhuman primates (NHP). SFV can be zoonotically transmitted to humans who either work with or live commensally with NHP. We analyzed the blood of 45 Bangladeshi performing monkey owners (an ethnic group called the Bedey) for SFV infection. Surprisingly, a PCR assay failed to detect SFV infection in any of these participants. This is in contrast to our previously reported infection rate of about 5% among Bangladeshi villagers.

This study investigates ultra-deep adsorptive desulfurization (ADS) from light-irradiated diesel fuel over supported TiO2–CeO2 adsorbents. A 30-fold higher desulfurization capacity of 95 mL of fuel per gram of adsorbent (mL-F/g-sorb) or 1.143 mg of sulfur per gram of adsorbent (mg-S/g-sorb) was achieved from light-irradiated fuel over the original low-sulfur fuel containing about 15 ppm by weight (ppmw) of sulfur. The sulfur species on spent TiO2–CeO2/MCM-48 adsorbent was identified by sulfur K-edge XANES as sulfones and the adsorption selectivity to different compounds tested in a model fuel decreases in the order of indole > dibenzothiophenesulfone ≫ dibenzothiophene > 4-methyldibenzothiophene > benzothiophene > 4,6-dimethyldibenzothiophene > phenanthrene > 2-methylnaphthalene ∼ fluorene > naphthalene. The results suggest that during ADS of light-irradiated fuel, the original sulfur species were chemically transformed to sulfones, resulting in the significant increase in desulfurization capacity. For di...

National Natural Science Foundation of China [21003109, 51108424]; program for Changjiang Scholars and Innovative Research Team in Chinese Universities [IRT0980]; program for Zhejiang Leading Team of Science and Technology Innovation [2009R50020]; Opening-foundation of State Key Laboratory Physical Chemistry and Solid Surfaces, Xiamen University, China [201311]; Science Foundation of Zhejiang Normal University [KJ20120028]

SummaryThe transcription factor HIF1A is a key mediator of the cellular response to hypoxia. Despite the importance of HIF1A in homeostasis and various pathologies, little is known about how it regulates RNA polymerase II (RNAPII). We report here that HIF1A employs a specific variant of the Mediator complex to stimulate RNAPII elongation. The Mediator-associated kinase CDK8, but not the paralog CDK19, is required for induction of many HIF1A target genes. HIF1A induces binding of CDK8-Mediator and the super elongation complex (SEC), containing AFF4 and CDK9, to alleviate RNAPII pausing. CDK8 is dispensable for HIF1A chromatin binding and histone acetylation, but it is essential for binding of SEC and RNAPII elongation. Global analysis of active RNAPII reveals that hypoxia-inducible genes are paused and active prior to their induction. Our results provide a mechanistic link between HIF1A and CDK8, two potent oncogenes, in the cellular response to hypoxia.

Significance A novel approach for ultra-deep desulfurization of diesel fuel was proposed, in which the original fuel was treated by light irradiation before adsorptive desulfurization (ADS) over the TiO2–CeO2/MCM-48 adsorbent under ambient conditions. A superior capacity of 95 cm3-fuel/g-adsorbent (32 times higher than that of the original fuel) was achieved. The promoting effect of light irradiation was likely through in situ peroxides generation in fuel under visible light/sunlight, which may oxidize organosulfur to form strongly adsorbed sulfones over the adsorbent.

In this work, an inexpensive and commercially available bentonite was modified by sulfuric acid and explored as the new type of support to immobilize tetraethylenepentamine (TEPA) for CO2 capture from flue gas. By applying sulfuric acid treatment, the textural properties, in particular, pore volume and surface area of bentonite, were significantly improved. Bentonite treated with 6 M sulfuric acid (Ben_H2SO4_6M) can reach a pore volume of 0.77 cc/g from that of the parent bentonite of 0.15 cc/g. With the maximum TEPA loading of 50 wt % onto the Ben_H2SO4_6M sorbent, the maximum CO2 breakthrough sorption capacity reached 130 mg of CO2/g of sorbent at 75 °C under a dry condition. With an addition of moisture to the simulated flue gas, the CO2 sorption capacity can be further improved to 190 mg of CO2 at 18 vol% of moisture addition sorbent due to the bicarbonate formation under a wet condition. The TEPA/Ben_H2SO4_6M sorbents show a good regenerability and thermal stability below 130 °C. The high CO2 sorptio...

A series of molecular basket sorbents consisting of SBA-15 loaded with different amounts of polyethylenimine (PEI) have been systematically studied, focusing on their characterization by small angle X-ray scattering (SAXS), N 2 physisorption, scanning electron microscopy (SEM), and thermogravimetric analysis (TGA) and their CO 2 sorption properties. The meso-structure of SBA-15 was retained after PEI loading. When the PEI loading was no more than 50 wt.%, PEI was dispersed and filled inside the pore channels of SBA-15. Higher PEI loading resulted in a part of the loaded PEI coating on the external surface of the SBA-15 particles and thus caused the agglomeration. The effects of sorption temperature and PEI loading on the CO 2 capacity of the PEI/SBA-15 sorbents were examined over a fixed-bed flow system using a model flue gas. The relationship between the sorption performance and the sorbent structure has been discussed. CO 2 diffusion in the PEI bulk may play a crucial role for determining the CO 2 sorption capacity and sorption/desorption rate at low temperature. With the increase of the sorption temperature, CO 2 diffusion can be accelerated and more amine sites may be exposed and accessible for CO 2 sorption. As a result, the sorption capacity increases. However, at further higher temperature, e.g., 100 °C, the sorption capacity decreases due to the dominant desorption. In addition, the sorption behavior of SBA-15 and PEI-50/SBA-15 at high CO 2 pressures (up to 50 bars) has been studied. The results showed that CO 2 sorption over PEI/SBA-15 occurs mainly via chemisorption even under pressurized conditions.

In recent years, tick-borne diseases like anaplasmosis have become widespread worldwide threatening the health of both human and animals. Dogs play an important role in the epidemiology of several zoonotic tick-borne pathogens by acting as reservoirs. In this study, the status of Anaplasma phagocytophilum, A. platys, A. bovis and A. ovis infection were assessed in dogs in Henan, China, with PCR and phylogenetic analyses. Nested PCRs on 243 blood samples collected from dogs from different sampling sites revealed that thirty-three (13.6%) dogs were positive for one or more pathogens. The prevalence of Anaplasma spp. in stray dogs was 40.7% (24/59), which was much higher than that of pet dogs (4.0%, 7/175). The prevalence for A. ovis, A. bovis and A. phagocytophilum was 6.2%, 4.1% and 0.4%, respectively and mixed-infection of these three pathogens was found in only one stray dog (prevalence, 0.4%). None of the dogs was positive for A. platys. Phylogenetic analyses classified A. phagocytophilum into two distinct groups (East Asia and south Africa group, Europe and America group), whereas A. ovis and A. bovis showed a general classification into two groups (cluster 1 and cluster 2), respectively. The isolate (KX190783) of A. ovis from a stray dog fell in a clade with a human isolate from Cyprus (FJ460443) and shared 99.8% similarity with it. To the best of our knowledge, this study is the first report to identify A. bovis and A. ovis DNA in dogs in China and the mixed-infection of the three Anaplasma spp. (A. phagocytophilum, A. bovis and A. ovis) in dogs.

In this paper, a modulation strategy based on zero-sequence voltage injection is proposed for module multilevel converter (MMC). By the proposed method, the remaining capacitor voltages not vary and the line-to-line voltages are balanced. This method is easy to be implemented by adjusting the voltage injection coefficient when SM fault occurs. The coefficient of injected zero-sequence voltage is designed by the number and position of the fault submodules (SMs) and the fault-tolerant capability of this method are also discussed. The effectiveness and advantages of proposed method are confirmed with simulation and experiment.

Theileria spp. and Anaplasma spp., which are important tick-borne pathogens (TBPs), impact the health of humans and animals in tropical and subtropical areas. Theileria and Anaplasma co-infections are common in sheep and goats. Following alignment of the relevant DNA sequences, two primer sets were designed to specifically target the Theileria spp. 18S rRNA and Anaplasma spp. 16S rRNA gene sequences. Genomic DNA from the two genera was serially diluted tenfold for testing the sensitivities of detection of the primer sets. The specificities of the primer sets were confirmed when DNA from Anaplasma and Theileria (positive controls), other related hematoparasites (negative controls) and ddH 2 O were used as templates. Fifty field samples were also used to evaluate the utility of single PCR and duplex PCR assays, and the detection results were compared with those of the PCR methods previously published. An optimized duplex PCR assay was established from the two primer sets based on the relevant genes from the two TBPs, and this assay generated products of 298-bp ( Theileria spp.) and 139-bp ( Anaplasma spp.). The detection limit of the assay was 29.4 × 10 −3 ng per μl, and there was no cross-reaction with the DNA from other hematoparasites. The results showed that the newly developed duplex PCR assay had an efficiency of detection (P > 0.05) similar to other published PCR methods. In this study, a duplex PCR assay was developed that can simultaneously identify Theileria spp. and Anaplasma spp. in sheep and goats. This duplex PCR is a potentially valuable assay for epidemiological studies of TBPs in that it can detect cases of mixed infections of the pathogens.

Nucleotide substitutions among some new genotypes of E. bieneusi from this study versus the reported genotype BEB6 (EU 153584). (DOC 132 kb)

In this work, we conducted a study on temperature-programmed desorption (TPD) of CO 2 over molecular basket sorbent (MBS) consisting of polyethylenimine (PEI) immobilized in mesoporous silica SBA-15. A series of MBS sorbents with different PEI loadings in SBA-15 have been studied for CO 2 -TPD to gain an insight into the fundamental characteristics of CO 2 sorption/desorption mechanism. Effects of sorption temperature, sorption time, and PEI molecular weight on the CO 2 sorption capacity and desorption behavior of 50 wt% PEI/SBA-15 sorbent were also examined. The results show that two PEI layers, i.e., the exposed PEI layer and the inner bulky PEI layer may exist in PEI/SBA-15 sorbents, and their proportions vary with PEI loading and sorption temperature. Consequently, a two-layer model for CO 2 sorption over PEI/SBA-15 sorbent is proposed, which rationalizes the sorption results with consideration of CO 2 sorption kinetics and thermodynamics. It was also found that CO 2 sorption capacity decreases with increasing PEI molecular weight, which may be mainly attributed to the decrease of primary amine content and the increase of tertiary amine content as well as increased interactions between polymeric chains in the PEI molecules.

In this paper, a solid molecular basket sorbent, 50 wt% PEI/SBA-15, was studied for CO(2) capture from gas streams with low CO(2) concentration under ambient conditions. The sorbent was able to effectively and selectively capture CO(2) from a gas stream containing 1% CO(2) at 75 °C, with a breakthrough and saturation capacity of 63.1 and 66.7 mg g(-1), respectively, and a selectivity of 14 for CO(2)/CO and 185 for CO(2)/Ar. The sorption performance of the sorbent was influenced greatly by the operating temperature. The CO(2)-TPD study showed that the sorbent could be regenerated under mild conditions (50-110 °C) and was stable in the cyclic operations for at least 20 cycles. Furthermore, the possibility for CO(2) capture from air using the PEI/SBA-15 sorbent was studied by FTIR and proved by TPD. A capacity of 22.5 mg g(-1) was attained at 75 °C via a TPD method using a simulated air with 400 ppmv CO(2) in N(2).

We previously identified a region of recurrent amplification on chromosome 22q11.21 in a subset of primary lung adenocarcinomas. Here we show that CRKL, encoding for an adaptor protein, is amplified and overexpressed in non–small cell lung cancer (NSCLC) cells that harbor 22q11.21 amplifications. Overexpression of CRKL in immortalized human airway epithelial cells promoted anchorage-independent growth and tumorigenicity. Oncogenic CRKL activates the SOS1-RAS-RAF-ERK and SRC-C3G-RAP1 pathways. Suppression of CRKL in NSCLC cells that harbor CRKL amplifications induced cell death. Overexpression of CRKL in epidermal growth factor receptor (EGFR)-mutant cells induces resistance to gefitinib by activating extracellular signal–regulated kinase and AKT signaling. We identified CRKL amplification in an EGFR inhibitor–treated lung adenocarcinoma that was not present before treatment. These observations demonstrate that CRKL overexpression induces cell transformation, credential CRKL as a therapeutic target for a subset of NSCLC that harbor CRKL amplifications, and implicate CRKL as an additional mechanism of resistance to EGFR-directed therapy. Significance: These studies credential CRKL as an oncogene in a subset of NSCLC. Overexpression of CRKL induces cell transformation and resistance to epidermal growth factor receptor inhibitor treatment and suggest that therapeutic interventions targeting CRKL may confer a clinical benefit in a defined subset of NSCLCs. Cancer Discovery; 1(7); 608–25. ©2011 AACR. Read the Commentary on this article by Ladanyi, p. 560 This article is highlighted in the In This Issue feature, p. 539

A series of hierarchical porous TS-1 zeolites had been successfully synthesized using cheap tetrapropylammonium bromide as microporous template and carbon material from sucrose carbonization as mesoporous template. The samples were characterized by powder X-ray diffraction, UV–Vis spectroscopy, FT-infrared spectroscopy, N 2 physical adsorption–desorption, scanning and transmission electron microscopy techniques. The catalytic performances of the obtained materials were investigated via the oxidation of both small and bulky molecular sulfur compounds (thiophene and benzothiophene) using H 2 O 2 as oxidant. The mesopores or macropores system is clearly demonstrated by N 2 adsorption–desorption isotherm, scanning and transmission electron microscopy images. Moreover, the hierarchical pores correspond well with the framework structure of the carbon template trapped in TS-1 crystals, which confirms the template effect of the carbon material from sucrose carbonization. The reaction results show that hierarchical porous TS-1 zeolites not only give high removal rates of small molecular thiophene, but also exhibit high activities in oxidation of bulky benzothiophene, which are superior to TS-1.

A solid oxide fuel cell with a nickel-yttria stabilized zirconia cermet anode and a porous lanthanum strontium manganite cathode was used to generate electrical power directly from anaerobic digester gas and commercial diesel steam reformate. A diesel reformer was combined with the solid oxide fuel cell system in a single operating unit to convert diesel to electricity. To model anaerobic digester gas (ADG), a fuel gas mixture was prepared based on analytical data on real ADG from a local water cleaning facility. Electrochemical performance characterization involved power generation across a variety of external loads to characterize open circuit potential, maximum power densities and limiting current densities. The effects of anode poisoning from of sulfur compounds and their removal from the ADG fuel were studied.

This study was performed to elucidate the influence of sulfur on the carbon deposition in steam reforming of liquid hydrocarbons over CeO 2 –Al 2 O 3 supported Ni and Rh catalysts at 800 °C. The characteristics of the carbon deposits on the used catalysts after the reactions without and with sulfur were investigated by temperature-programmed oxidation (TPO), transmission electron microscopy (TEM), scanning transmission X-ray microscopy (STXM), temperature-programmed hydrogenation (TPH), X-ray absorption near edge structure (XANES), and scanning electron microscopy (SEM). Though abundant carbon deposits can accumulate on the pure CeO 2 –Al 2 O 3 support due to fuel thermal cracking, the addition of Ni or Rh metal greatly reduced the carbon deposition in the sulfur-free reaction. The presence of sulfur increased the carbon deposition on both catalysts, which has a much more significant impact for the Ni catalyst. Carbon XANES study on the used catalysts revealed that graphitic carbon was dominant in the presence of sulfur, while oxidized carbon species (quinone-like carbon, carboxyl and carbonate) prevailed without sulfur. Meanwhile, the formation of carboxyl and carbonate more dramatically dropped on the Ni catalyst than that on the Rh catalyst. Our results strongly suggest that (I) the presence of sulfur can suppress carbon gasification and promote the formation of graphitic carbon on reforming catalysts due mainly to its poisoning effect on metals, and (II) Rh catalyst possesses stronger capability to maintain carbon gasification activity than Ni catalyst in the presence of sulfur.

Three strains BQ, BJ, and BS utilizing benzoic acid as the sole carbon source were achieved from Yichang City, Hubei Province, China, through selective enrichment and domestication. Both BQ and BJ were primarily identified as Acinetobacter. spp while BS was Geotrichum. spp. After three domestications, the removal rates of BQ, BJ, and BS to chemical oxygen demand (COD) value of benzoic acid were 62.41%, 94.44%, and 43.34%, respectively. The strains were mixed cultured, and the degradation rates of strains to benzoic acid at different temperature, pH and benzoic acid concentration were determined. The results show that the optimum degradation conditions about strains were pH 7.0, temperature 30 °C, and aerobic with 1 500 mg/L of concentration of benzoic acid. In this condition, the COD removal rate of strains to benzoic acid reached 84.93%.

Wormlike/lamellar microporous carbons were prepared by using long alkyl chain primary amine hydrochloride as the template and resorcinol/formaldehyde as the carbon source under highly acidic conditions. The template can be eliminated by high temperature treatment under an inert atmosphere. The obtained carbon materials were characterized by N2 adsorption-desorption, transmission electron microscopy, thermogravimetry and scanning electron microscopy. The results show that dodecylamine hydrochloride surfactant can be used as the template of wormlike micropores structure while octadecylamine hydrochloride results in both lamellar and wormlike micropores. The obtained carbon materials have the similar pore size in the range of 0.5∼0.59 nm, but with various morphologies such as monolith, spheres, and coralline. The microporous carbon obtained from dodecylamine hydrochloride surfactant shows good adsorption performance to remove the refractory sulfur compounds and nitrogen-containing compounds in fuel.

Mesoporous molecular sieve Ti-HMS, which possesses uniform wormlike structure and high specific surface area, was used as the support of anti-inflammatory drug ibuprofen. The samples before and after charging with ibuprofen were characterized using X-ray diffraction, UV–visible and thermal gravimetry. The loading amount and release rates on Ti-HMS with different titanium content and pore size were investigated systematically. It has been shown that Ti-HMS can adsorb ibuprofen and be used in drug delivery system. With the increase of framework titanium content, the loading amount of ibuprofen increases. The larger pore size also facilitates the loading and release of ibuprofen.

A diversity of strategies is evolved by RNA viruses to manipulate the host translation machinery in order to create an optimal environment for viral replication and progeny production. One of the common viral targets is the α subunit of eukaryotic initiation factor 2 (eIF-2α). In this report, we show that phosphorylation of eIF-2α was severely suppressed in human and animal cells infected with the coronavirus infectious bronchitis virus (IBV). To understand whether this suppression is through inhibition of protein kinase R (PKR), the double-stranded-RNA-dependent kinase that is one of the main kinases responsible for phosphorylation of eIF-2α, cells infected with IBV were analyzed by Western blotting. The results showed that the level of phosphorylated PKR was greatly reduced in IBV-infected cells. Overexpression of IBV structural and nonstructural proteins (nsp) demonstrated that nsp2 is a weak PKR antagonist. Furthermore, GADD34, a component of the protein phosphatase 1 (PP1) complex, which dephosphorylates eIF-2α, was significantly induced in IBV-infected cells. Inhibition of the PP1 activity by okadaic acid and overexpression of GADD34, eIF-2α, and PKR, as well as their mutant constructs in virus-infected cells, showed that these viral regulatory strategies played a synergistic role in facilitating coronavirus replication. Taken together, these results confirm that IBV has developed a combination of two mechanisms, i.e., blocking PKR activation and inducing GADD34 expression, to maintain de novo protein synthesis in IBV-infected cells and, meanwhile, to enhance viral replication.

Carbon materials were prepared using mesoporous silica HMS with different pore sizes as the hard templates and water-soluble phenolic resin as the carbon source. The obtained materials were characterized by powder X-ray diffraction, transmission electron microscopy and N2 physical adsorption, and were used in adsorptive desulfurization. It has been shown that the carbon material prepared using HMS with larger pore size (>3 nm) presented uniform wormlike mesopore of 2.3 nm and large BET surface area (1903 m2/g). The mesoporous carbon was an excellent adsorbent to remove the refractory sulfur compound in diesel, especially dibenzothiophene and 4, 6-dimethyldibenzothiophene.

Because of gravitational differentiation of multi-phase fluids, gas-water flow is usually stratified in highly inclined or horizontal gas wells. By using electrode arrays to scan flowing fluids, electromagnetic tomography can identify the flow patterns of mixed fluid from the different electrical properties of gas and water. The responses for different gas-water interface locations were calculated and then physical measurements were undertaken. We compared the results of the numerical simulation with the experimental data, and found that the response characteristics were consistent in the circumstances of uniform physical fields and stratified flows. By analyzing the signal characteristics, it is found that, with the change of the interface location, the response curves showed “steps” whose position and width were decided by the location of fluid interface. The measurement accuracy of this method depended on the vertical distance between adjacent electrodes. The results showed that computer simulation can simulate the measurement of the electromagnetic tomography accurately, so the physical experiment can be replaced.

A new generation of "molecular basket" sorbents (MBS) has been developed by the optimum combination of the nanoporous material and CO(2)/H(2)S-philic polymer sorbent to increase the accessible sorption sites for CO(2) capture from flue gas (Postdecarbonization), and for CO(2) and H(2)S separation from the reduced gases, such as synthesis gas, reformate (Predecarbonization), natural gas, coal/biomass gasification gas, and biogas. The sorption capacity of 140 mg of CO(2)/g of sorb was achieved at 15 kPa CO(2) partial pressure, which shows superior performance in comparison with other known sorbents. In addition, an exceptional dependence of MBS sorption performance on temperature for CO(2) and H(2)S was found and discussed at a molecular level via the computational chemistry approach. On the basis of the fundamental understanding of MBS sorption characteristics, an innovative sorption process was proposed and demonstrated at the laboratory scale for removing and recovering CO(2) and H(2)S, respectively, from a model gas. The present study provides a new approach for development of the novel CO(2)/H(2)S sorbents and may have a major impact on the advance of science and technology for CO(2)/H(2)S capture and separation from various gases.

The influence of ceria and nickel addition to alumina-supported Rh catalyst for steam reforming of propane at low temperatures has been studied by preparing and examining 2 wt%Rh/Al 2 O 3 , 2 wt%Rh/20 wt%CeO 2 –Al 2 O 3 , and 2 wt%Rh–5 wt%Ni/20 wt%CeO 2 –Al 2 O 3 . TPR characterization showed that adding ceria makes rhodium oxide easier to reduce and the presence of rhodium also makes ceria easier to reduce through Rh–Ce interaction, whereas the addition of Ni makes Rh 2 O 3 and ceria more difficult to reduce, likely due to Rh–Ni and Ce–Ni interactions. Adding ceria and nickel significantly improved the catalytic activity of Rh catalyst for propane conversion at 475 °C. Kinetic study at different temperatures (450–650 °C) indicated that the addition of ceria and Ni can greatly increase the propane reforming rates by lowering the activation energies from 67.6–68.8 kJ/mol for 2Rh/Al to 50.1–50.4 kJ/mol for 2Rh/20CeAl and to 42.1–42.5 kJ/mol for 2Rh5Ni/20CeAl. The feed steam/carbon molar ratios corresponding to maximum reaction rates at 475 °C increased from 2.0 for 2Rh/Al to 3.0 for 2Rh/20CeAl and 4.5 for 2Rh5Ni/20CeAl catalyst. A kinetic equation based on Langmuir–Hinshelwood model best fitting the experimental data was applied for the propane steam reforming over the Rh-based catalysts. Kinetic results at different partial pressures of propane and steam revealed that the addition of ceria could enhance the steam and propane adsorption, while the addition of Ni could significantly promote the propane adsorption, probably through working with Rh as propane adsorption sites.

Multiphase flow in an oil well is a dynamic phenomenon of inhomogeneous medium, which should be studied in a nonlinear way. This paper presents an electromagnetic measurement method based on the electrical property differences between oil, gas and water to scan, inverse and show the distribution and condition of multiphase flow. Both numerical simulation and physical experiments have proved that clear images could be obtained by this way.

A series of sorbents with a linear polyethylenimine (PEI) supported on the mesoporous molecular sieves, including MCM-41, MCM-48 and SBA-15, have been prepared and used to remove H2S from a model gas containing 0.40 v% of H2S and 20 v% H2 in N2 gas. The sorption was conducted in a fixed-bed system at a temperature range of 22–75 °C, a GHSV range of 337–1,011 h−1 and atmospheric pressure. The effects of the operating temperature, GHSV, the amount of PEI loading and the different molecular sieve supports were studied. A reduction in the temperature and GHSV improves the sorption performance of the supported PEI sorbents. A synergetic effect of the SBA−15 support and PEI on the H2S sorption performance was observed. Loading 50 wt% PEI on SBA-15 gave the best breakthrough capacity, while loading 65 wt% PEI on SBA-15 had the highest saturation capacity. The mesoporous molecular sieve with large pore size and three-dimensional channel structure favors increasing the kinetic capacity of the supported PEI sorbent. In addition, the developed sorbents can be regenerated easily at mild conditions (temperature range of 75–100 °C) and have excellent regenerability and stability. The results indicate that the mesoporous-molecular-sieve-supported polymer sorbents are promising for removing H2S from hydrogen gas streams.

Summary Shugoshin 1 (Sgo1) functions as a protector of centromeric cohesion of sister chromatids in higher eukaryotes. Here, we provide evidence for a previously unrecognized role for Sgo1 in centriole cohesion. Sgo1 depletion via RNA interference induces the formation of multiple centrosome-like structures in mitotic cells that result from the separation of paired centrioles. Sgo1 +/− mitotic murine embryonic fibroblasts display split centrosomes. Localization study of two major endogenous splice variants of Sgo1 indicates that the smaller variant, sSgo1, is found at the centrosome in interphase and at spindle poles in mitosis. sSgo1 interacts with Plk1 and its spindle pole localization is Plk1 dependent. Centriole splitting induced by Sgo1 depletion or expression of a dominant negative mutant is suppressed by ectopic expression of sSgo1 or by Plk1 knockdown. Our studies strongly suggest that sSgo1 plays an essential role in protecting centriole cohesion, which is partly regulated by Plk1.

We have previously reported that polysaccharides extracted from Pyracantha fortuneana (Maxim.) Li (P. fortuneana) lowered the oxidative stress and inhibited the inflammatory responses in mice. Our present study aims to determine the effects of Selenium enriched P. fortuneana polysaccharides (Se-PFPs) against carbon tetrachloride (CCl 4 )-induced liver injury in a mouse model. Our results displayed that CCl4 remarkably elevated the levels of alanine transferase (ALT), aspartate transaminase (AST), lactic dehydrogenase (LDH), cholesterol, triglycerides in serum. However, similar to BP treatment, supplementation of mice with Se-PFPs resulted in reversal of ALT, AST, LDH, cholesterol, triglycerides in serum. Contrary to CCl 4 , supplementation of mice with Se-PFPs elevated the activities of superoxide dismutase (SOD), glutathione peroxidase (GPx) and levels of glutathione (GSH) in liver. Furthermore, Se-PFPs treatment increased the expression of GPx and catalase (CAT) at mRNA and protein levels in liver which were decreased in CCl 4 group. Contrary to CCl 4 , Se-PFPs supplement decreased the levels of thiobarbituric acid reactive substances (TBAR) and H 2 O 2 , which served as lipid peroxidation biomarker. Our study indicates that Se-PFPs administration is effective in attenuating CCl 4 -induced liver injury. The mechanism underlying this effect may be attributed to the reduction of oxidative stress and inflammation in the liver by Se-PFPs through up-regulation of the antioxidant system. Our study suggests that Se-PFPs might be a potential dietary agent in the prevention of hepatic damage.

Decomposition methods of the Suzuki-Trotter type of various orders have been derived in different fields. Applying them both to classical ordinary differential equations (ODEs) and quantum systems allows to judge their effectiveness and gives new insights for many body quantum mechanics where reference data are scarce. Further, based on data for 6 × 6 system we conclude that sampling with sign (minus-sign problem) is probably detrimental to the accuracy of fermionic simulations with determinant algorithms.

Viruses depend heavily on host cells for replication and exploit the host translation machinery for its gene expression using various unorthodox translation mechanisms. According to the conventional scanning model, only the 5'-proximal gene in the viral RNA is accessible to the ribosomes whereas other genes are silent. In this study, we use a model plant RNA virus, Hibiscus chlorotic ringspot virus (HCRSV), to investigate various translation mechanisms involved in regulation of the expression of internal genes. The 3'-end 1.2kb region of HCRSV genomic and subgenomic RNAs were shown to encode four polypeptides of 38, 27, 25 and 22.5kDa. Mutagenesis studies revealed that a CUG codon ((2570)CUG) is the initiation codon for p27, the longest of the three co-C-terminal products (p27, p25 and p22.5), and translation of p25 and p22.5 was initiated at (2603)AUG and (2666)AUG, respectively. Translation initiation of the p27 expression at the (2570)CUG codon regulates the expression of p38, the viral coat protein through a leaky scanning mechanism and mutational analysis of an upstream open reading frame (ORF) demonstrated that initiation of the p27 expression at this CUG codon (instead of an AUG) may play a role in maintaining the ratio of p27 and p38. In addition, a previously identified internal ribosome entry site was shown to control the expression of p27 and p38 in the subgenomic RNA 2.

Mesoporous molecular sieves containing iron sites with different dispersions and environments were studied for the partial oxidation of methane and the epoxidation of propylene. The tetrahedral Fe(III) sites incorporated inside the framework of SBA-15 showed higher HCHO selectivity under a similar CH4 conversion than the oligomeric FeOx clusters located in the mesopores in the partial oxidation of CH4 by O2. HCHO selectivity of the FeOx clusters in SBA-15 could be improved by the modification with either an acidic group (e.g., phosphate) or an alkali metal ion, which increased the dispersion or changed the local coordination environment of iron species. The catalyst containing FePO4 clusters formed by the modification with phosphate exhibited the best catalytic performances for HCHO formation. This catalyst also showed uniquely high selectivities to HCHO and CH3OH as N2O was used as the oxidant for the partial oxidation of CH4. For the epoxidation of propylene to propylene oxide (PO), the modification of the FeOx/SBA-15 with an alkali metal salt typified by KCl was effective. Among many SBA-15-supported transition metal oxides modified by KCl, the KCl-FeOx/SBA-15 showed the best catalytic performances for the epoxidation of propylene by N2O. The comparative studies using N2O and O2 as the oxidant revealed that N2O was necessary for PO formation over the KCl-FeOx/SBA-15 catalyst.

Alkali metal salt (KCl)-modified Fe-MFI and Fe-MCM-41 containing iron species in different locations have been studied for the epoxidation of propylene with nitrous oxide. In the allylic oxidation of propylene without modification, the samples with iron species in the framework positions showed slightly higher activity for the formation of acrolein and allyl alcohol. After modification with KCl, propylene oxide (PO) became the main product. Significant differences in PO formation activity were observed between the samples containing iron in different locations. For the Fe-MFI and the Fe-MCM-41 prepared by the direct hydrothermal (DHT) method, in which iron was located mainly in the framework position, much lower activity was obtained after KCl modification. In contrast, the Fe-MFI after steam treatment and the Fe-MCM-41 prepared by template ion-exchange (TIE) and conventional impregnation methods, which contained extra-framework iron species (e.g., FeO x clusters), exhibited higher PO formation activity after modification. A PO selectivity of 80% could be achieved at a propylene conversion of 3.3% over the KCl-modified Fe-MCM-41 prepared by the TIE or the impregnation method at 598 K (time on stream, 70 min). The modification with KCl increased the dispersion of the extra-framework iron species. Consequently, highly dispersed extra-framework iron species, probably in tetrahedral coordination, are proposed for the epoxidation of propylene with nitrous oxide.

Sgo1 is an evolutionarily conserved protein that functions as a protector of centromeric cohesin during mitosis. Recent studies show that Sgo1 is kinetochorelocalized and required for accurate segregation of mitotic chromosomes because depletion of Sgo1 in mammalian cells results in precocious initiation of anaphase and mis-segregation of chromosomes. Through analysis of GFP fusion proteins, we observe that two major isoforms of human Sgo1 exhibit entirely different subcellular localization patterns. The short isoform of Sgo1 (sSgo1) that lacks exon 6 does not localize to kinetochores during any stages of the cell cycle. Instead, it is enriched at mitotic spindles. On the other hand, the longer isoform of Sgo1 primarily localizes to kinetochores during G(2) phase and mitotic prophase, metaphase, and anaphase. During late mitosis, Sgo1 does not appear to be associated with kinetochores. Intriguingly, the longer isoform of Sgo1 forms discrete foci during S phase, some of which are apparently in the nucleoli. However, a majority of these foci colocalize with CREST, a kinetochore antigen, indicating that Sgo1 is loaded onto kinetochores during or immediately after DNA replication. Together, our studies suggest that different isoforms of Sgo1 may play distinct roles during the cell cycle and that Sgo1 may have an interphase function as well.

Programmed frameshifting is one of the translational recoding mechanisms that read the genetic code in alternative ways. This process is generally programmed by signals at defined locations in a specific mRNA. In this study, we report the identification of hepta- and octo-uridine stretches as sole signals for programmed +1 and -1 ribosomal frameshifting during translation of severe acute respiratory syndrome coronavirus (SARS-CoV) ORF 3a variants. SARS-CoV ORF 3a encodes a minor structural protein of 274 amino acids. Over the course of cloning and expression of the gene, a mixed population of clones with six, seven, eight and nine T stretches located 14 nt downstream of the initiation codon was found. In vitro and in vivo expression of clones with six, seven and eight Ts, respectively, showed the detection of the full-length 3a protein. Mutagenesis studies led to the identification of the hepta- and octo-uridine stretches as slippery sequences for efficient frameshifting. Interestingly, no stimulatory elements were found in the sequences upstream or downstream of the slippage site. When the hepta- and octo-uridine stretches were used to replace the original slippery sequence of the SARS-CoV ORF 1a and 1b, efficient frameshift events were observed. Furthermore, the efficiencies of frameshifting mediated by the hepta- and octo-uridine stretches were not affected by mutations introduced into a downstream stem-loop structure that totally abolish the frameshift event mediated by the original slippery sequence of ORF 1a and 1b. Taken together, this study identifies the hepta- and octo-uridine stretches that function as sole elements for efficient +1 and -1 ribosomal frameshift events.

Evaluation of: Daniels MJ, Wang Y, Lee M, Venkitaraman AR: Abnormal cytokinesis in cells deficient in the breast cancer susceptibility protein BRCA2. Science 306, 876–879 (2004). Cytokinesis is the division of the cytoplasm of a parent cell into daughter cells after nuclear division. Cytokinesis failure is often accompanied by the generation of cells with an unstable tetraploidy content, which predisposes the cells to develop aneuploidy and malignancies. A recent study by Venkitaraman’s group demonstrates that BRCA2, a breast cancer susceptibility gene product, also functions in mediating normal cytokinesis. Similar to the subcellular localization of Aurora kinase, BRCA2 is present at the cleavage furrow and the midbody during late mitosis. Deficiency in BRCA2 function results in cytokinesis failure, which is associated with abnormal localization of myosin II, a key protein essential for the formation of the cleavage furrow. This study is of significance as it shows for the first time that BRCA2 has a function in controlling mitotic exit, deregulation of which contributes to gross genomic instabilities in daughter cells.

To ensure sister chromatids to be equally transmitted to daughter cells, it is imperative that physical association of sister chromatids is maintained during S, G2, and early mitosis until the onset of anaphase. Cohesion of sister chromatids in eukaryotes is largely achieved by the cohesin complex. In vertebrates, cohesin molecules are dissociated from chromosome arms but not from centromeres during prophase by the so-called prophase pathway. Although it remains unclear what is the molecular basis by which centromeric cohesin is retained, a flurry of recent studies have shed light on a family of proteins named Shugoshin (Sgo) that are evolutionarily conserved across eukaryotes. Sgo1 functions as a protector of centromeric cohesin during meiosis in yeast and during mitosis in high eukaryotes. Suppression of Sgo1 function results in premature separation of sister chromatids in both meiosis and mitosis. The discovery of members of the Sgo family may help to explain how centromeric cohesin is protected from dissociation from DNA until the onset of anaphase. Given the importance of chromosome cohesion in the maintenance of genomic stability, further characterization of Sgo1 and related molecules may also open up new avenues of research for developing new strategies for cancer intervention.

The coordination structures of vanadium and iron introduced into MCM-41, a typical mesoporous silica, by both direct hydrothermal synthesis (DHT) and template–ion exchange (TIE) methods have been studied by X-ray absorption spectroscopy (XANES and EXAFS). Vanadium is tetrahedrally coordinated with oxygen in V-MCM-41 prepared by both methods but the location of vanadium is probably different; vanadium is mainly incorporated inside the framework of MCM-41 by the DHT method as the content is lower than approximately 1 wt%, while the vanadyl tetrahedra are probably dispersed on the wall surface of MCM-41 over the samples by the TIE method. In the case of Fe-MCM-41, the DHT method results in iron atoms mainly in tetrahedral coordination and isolated from each other in the framework of MCM-41. However, aggregated iron oxides with iron in octahedral coordination are mainly observed in the TIE samples. The V-MCM-41 by the TIE method shows better catalytic performances than that by the DHT method in the partial oxidation of methane to formaldehyde with oxygen. However, the Fe-MCM-41 by the DHT method exhibits remarkably higher methane conversion and formaldehyde selectivity than that by the TIE method.