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181.

In this work, a photobioreactor with microalgae biofilm was proposed to enhance CO2 biofixation and protein production using nickel foam with the modified surface as the carrier for immobilizing microalgae cells. The results demonstrated that, compared with microalgae suspension, microalgae biofilm lowered mass transfer resistance and promoted mass transfer efficiency of CO2 from the bubbles into the immobilized microalgae cells, enhancing CO2 biofixation and protein production. Moreover, parametric studies on the performance of the photobioreactor with microalgae biofilm were also conducted. The results showed that the photobioreactor with microalgae biofilm yielded a good performance with the CO2 biofixation rate of 4465.6 µmol m−3 s−1, the protein concentration of effluent liquid of 0.892 g L−1, and the protein synthesis rate of 43.11 g m−3 h−1. This work will be conducive to the optimization design of microalgae culture system for improving the performance of the photobioreactor.

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182.
<正>Epigenetics refers to how chromatin-associated factors and reversible chromatin modifications maintain DNA-based programs by regulating the chromatin structure (Strahl and Allis,2000).In recent years,genome sequencing studies of cancer have shown that genes encoding epigenetic factors are commonly mutated in cancer(Garraway and Lander,2013).Dys regulated,or mutant,epigenetic factors influence tumorigenesis progression (Dawson and Kouzarides,  相似文献   
183.
Severe fever with thrombocytopenia syndrome(SFTS) is an emerging hemorrhagic fever disease caused by SFTSV, a newly discovered phlebovirus that is named after the disease. Currently, no effective vaccines or drugs are available for use against SFTSV infection, as our understanding of the viral pathogenesis is limited. Bortezomib(PS-341), a dipeptideboronic acid analog, is the first clinically approved proteasome inhibitor for use in humans. In this study, the antiviral efficacy of PS-341 against SFTSV infection was tested in human embryonic kidney HEK293 T(293 T) cells. We employed four different assays to analyze the antiviral ability of PS-341 and determined that PS-341 inhibited the proliferation of SFTSV in 293 T cells under various treatment conditions. Although PS-341 did not affect the virus absorption, PS-341 treatment within a non-toxic concentration range resulted in a significant reduction of progeny viral titers in infected cells.Dual-luciferase reporter assays and Western blot analysis revealed that PS-341 could reverse the SFTSV-encoded nonstructural protein(NS) mediated degradation of retinoic acid-inducible gene-1(RIG-I), thereby antagonizing the inhibitory effect of NSs on interferons and blocking virus replication. In addition, we observed that inhibition of apoptosis promotes virus replication. These results indicate that targeting of cellular interferon pathways and apoptosis during acute infection might serve as the bases of future therapeutics for the treatment of SFTSV infections.  相似文献   
184.
Liu  Xi  Ding  Li  Yuan  Jing  Liao  Jian  Duan  Lian  Wang  Wenfei  Tan  Weiguo  Yu  Weiye  Zhou  Boping  Chen  Xinchun  Yang  Zheng 《中国病毒学》2019,34(3):334-337
<正>Dear Editor,H7 N9 is a recently identified subtype of influenza A virus that caused a major outbreak in humans in China in 2013.According to the latest data provided by the Chinese Center for Disease Control and Prevention(http://www.moh.gov.cn/zwgk/yqbb3/ejlist.shtml, updated on October 31, 2018),the mortality rate of H7 N9 infections in China amounts to  相似文献   
185.
<正>Dear Editor,Noroviruses are positive-sense, single-stranded RNA viruses belonging to Caliciviridae and account for more than 50%of all acute gastroenteritis (AGE) outbreaks worldwide and cause an estimated 200,000 deaths per year among children\5 years of age, primarily in developing countries (Hall et al. 2012; Glass et al. 2009). The norovirus genome contains three open reading frames (ORFs).  相似文献   
186.
Tao  Z. H.  Dong  H. M.  Duan  Y. F.  Huang  F.  Liu  J. L. 《Plasmonics (Norwell, Mass.)》2019,14(4):839-843
Plasmonics - We investigate on the terahertz (THz) plasmons of hole gas in monolayer MoS2 in the presence of spin-orbit interactions (SOIs) under the random phase approximation. The study shows...  相似文献   
187.
Transition metal layered oxides have been the dominant cathodes in lithium‐ion batteries, and among them, high‐Ni ones (LiNixMnyCozO2; x ≥ 0.7) with greatly boosted capacity and reduced cost are of particular interest for large‐scale applications. The high Ni loading, on the other hand, raises the critical issues of surface instability and poor rate performance. The rational design of synthesis leading to layered LiNi0.7Mn0.15Co0.15O2 with greatly enhanced rate capability is demonstrated, by implementing a quenching process alternative to the general slow cooling. In situ synchrotron X‐ray diffraction, coupled with surface analysis, is applied to studies of the synthesis process, revealing cooling‐induced surface reconstruction involving Li2CO3 accumulation, formation of a Li‐deficient layer and Ni reduction at the particle surface. The reconstruction process occurs predominantly at high temperatures (above 350 °C) and is highly cooling‐rate dependent, implying that surface reconstruction can be suppressed through synthetic control, i.e., quenching to improve the surface stability and rate performance of the synthesized materials. These findings may provide guidance to rational synthesis of high‐Ni cathode materials.  相似文献   
188.
Aims Elevated anthropogenic nitrogen (N) deposition could alter N status in temperate steppe. However, threshold observations of N status change from N limit to N saturation by far are not conclusive in these ecosystems. Research on the natural abundance of15N (δ15N) could greatly help provide integrated information about ecosystem N status. The goal of this study was to investigate the suitability of measurements of δ15N of major ecosystem N pools and several key species, plant15N fractionation, together with key vegetation and soil indicators in response to N fertilization as a tool to identify the N status in a temperate steppe in Inner Mongolia.  相似文献   
189.
The mechanism on of how salinity affects seed fatty acids accumulation remains unclear in halophytes. The present results revealed that the content of total unsaturated fatty acids in black seeds was higher than in brown seeds in the euhalophyte Suaeda salsa under controlled saline conditions. Salinity (200?mM NaCl) significantly increased the total oil content, unsaturated acid/saturated acid ratio, and content of α-linolenic acid (C18:3) (ALA), especially in brown seeds. The most abundant fatty acid in dimorphic seeds is linoleic acid (C18:2) (>70%). It appears that more ALA accumulated in brown seeds compared to black seeds. The enzyme activity of omega-3 fatty acid desaturase (ω-3 FAD) in brown seeds was much higher than that in black seeds, but salinity had no significant effect on the activity of ω-3 FAD in both brown and black seeds. The relative expression of SsFAD7 was increased by salinity, and the value in brown seeds was much higher than that in black seeds. This means salinity can, salinity can improve the quantity of fatty acids in dimorphic seeds of S. salsa, and the enzyme of ω-3 FAD and SsFAD7 may involve in the accumulation of ALA in dimorphic seeds under salinity.  相似文献   
190.
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