Aims
The aim of this study was to determine the effects of unsaturated fatty acids on clinical plasmids.
Methods and Results
Two unsaturated fatty acids, linoleic acid (LA) and α‐linolenic acid (ALA) ...at final concentration 0, 0·03, 0·3 and 3 mmol l−1, respectively, were used to assess the effects on conjugative transfer of a mcr‐1‐harbouring plasmid pCSZ4 (IncX4) in conjugation experiment. The inhibitory mechanisms were analysed by molecular docking and the gene expression of virB11 was quantitated by qRT‐PCR. Target plasmid diversity was carried out by TrwD/VirB11 homology protein sequence prediction analysis. Our results showed that LA and ALA inhibit plasmid pCSZ4 transfer by binding to the amino acid residues (Phe124 and Thr125) of VirB11 with dose‐dependent effects. The expression levels of virB11 gene were also significantly inhibited by LA and ALA treatment. Protein homology analysis revealed a wide distribution of TrwD/VirB11‐like genes among over 37 classes of plasmids originated from both Gram‐negative and Gram‐positive bacteria.
Conclusions
This study demonstrates representing a diversity of plasmids that may be potentially inhibited by unsaturated fatty acids.
Significance and Impact of the Study
Our work reported here provides additional support for application of curbing the spread of multiple plasmids by unsaturated fatty acids.
The endosymbiont Wolbachia is known for manipulating host reproduction in selfish ways. However, the molecular mechanisms have not yet been investigated in embryos. Here, we found that Wolbachia had ...no effect on the number of deposited eggs in Tetranychus urticae Koch (Acari: Tetranychidae) but caused two types of reproductive manipulation: killing uninfected female embryos via cytoplasmic incompatibility (CI) and increasing the hatching ratio of infected female embryos. RNA sequencing analyses showed that 145 genes were differentially expressed between Wolbachia‐infected (WI) and Wolbachia‐uninfected (WU) embryos. Wolbachia infection down‐regulated messenger RNA (mRNA) expression of glutathione S‐transferase that could buffer oxidative stress. In addition, 1613 and 294 genes were identified as CI‐specific up‐/down‐regulated genes. Compared to WU and WI embryos, embryos of CI cross strongly expressed genes involved in transcription, translation, tissue morphogenesis, DNA damage and mRNA surveillance. In contrast, most of the genes associated with energy production and metabolism were down‐regulated in the CI embryos compared to the WU and WI embryos, which provides some clues as to the cause of death of CI embryos. These results identify several genes that could be candidates for explaining Wolbachia‐induced CI. Our data form a basis to help elucidate the molecular consequences of CI in embryos.
Wolbachia induced incomplete cytoplasmic incompatibility (CI) in spider mites.
The CI embryos up‐regulated more genes associated with transcription, translation, and DNA damage compared with Wolbachia‐infected (WI) and Wolbachia‐uninfected (WU) embryos.
The CI embryos developed more slowly during hatching and expressed fewer energy production and metabolism genes compared with WI and WU embryos.
•The flow boiling experiment are conducted in porous-wall (PW) microchannels.•The effect of mass flux, heat flux and vapor quality on microchannels are studied.•PW microchannels reduce the wall ...superheat for ONB and improve the CHF.•PW microchannels exhibit obvious heat transfer enhancement with pressure drop reduction.•The uniformity and stability of wall temperature are analyzed in PW microchannels.
In this work, we proposed a porous-wall (PW) microchannel heat sink, in which micro pin fin arrays were fabricated on sidewalls of rectangular microchannels by MEMS (Microelectrical Mechanical System) technique. High speed flow visualizations were performed simultaneously with heat transfer and pressure drop measurements to investigate the flow boiling characteristics of PW microchannel heat sink. Conventional rectangular (Rec) microchannel heat sink was also explored together as a comparison. Experiments were carried out with pure acetone liquid at inlet temperature of 30 °C, mass flux from 255 kg/(m2·s) to 843 kg/(m2·s), heat flux from 4 W/cm2 to 110 W/cm2 and the maximum vapor quality at the outlet of the channel was 0.88. Experimental results demonstrated that the PW microchannels reduce wall superheat of onset of nucleate boiling (ONB) and improve critical heat flux (CHF) compared to the Rec microchannels. Moreover, the PW microchannels show significant heat transfer enhancement, pressure drop reduction and mitigation of two-phase flow instability. The porous walls provide numerous nucleation sites and the intensive pin fins arrangements introduce significant wicking effect to maintain the liquid rewetting, which contribute to the above notable flow boiling enhancement.
A compositive synthesis of gel polymer electrolytes by blending poly(propylene carbonate) (PPC) into poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP) as a polymer host is proposed. The ...blending polymer is produced by a facile solution casting method and ester groups of PPC are successful introduced into PVDF-HFP. The gel polymer electrolyte displays an excellent ion conductivity of 1.18 × 10−3 S cm−1, broad electrochemical window up to 4.8 V (vs. Li/Li+) and outstanding electrochemical stability within rechargeable lithium batteries at room temperature. The improvement of ion conductivity is attributed to the decrease of polymer crystallizability and the increase of micro pores. The strategy of blending is promising for the modification of PVDF-HFP electrolyte and foreground application in next-generation solid energy conversion devices.
All-solid-state lithium batteries (ASSLIBs) employed inorganic solid electrolytes are attracting increasing interest for electrochemical energy storage devices due to their advantages of high safety, ...high energy density, wide operating temperature range and long cycle life. However, the large interfacial resistance originated from the insufficient solid-solid contact at electrolyte/electrode interface hinders the development of all-solid-state batteries. In addition, the interfacial compatibility and stability also greatly affect the electrochemical performance of batteries. This review summarizes the challenges and progress for the studies of interface problems in ASSLIBs. Based on the review, we attempt to propose alternative approaches to the issue and prospective developments of ASSLIBs.
•All-solid-state cells with inorganic electrolytes suffer from interface problems.•Challenges and recent progress of the interface problems are summarized.•Great effort is needed to enable solid batteries as viable energy storages.
Porous NiCo2O4 hetero-structure arrays on nickel foam are prepared by a facile hydrothermal method. The morphology of the arrays changes with the growth time. After hydrothermal synthesis for 8 h in ...combination with annealing treatment, the NiCo2O4 array presents a nanoflake–nanowire hetero-structure. The porous NiCo2O4 hetero-structure array exhibits the excellent pseudocapacitive properties in 2 M KOH, with a high capacitance of 891 F g−1 at 1 A g−1 and 619 F g−1 at 40 A g−1 before activation as well as excellent cycling stability. The specific capacitance can achieve a maximum of 1089 F g−1 at a current density of 2 A g−1, which can still retain 1058 F g−1 (97.2% retention) after 8000 cycles. The enhanced pseudocapacitive performances are mainly attributed to its unique hetero-structure which provides fast ion and electron transfer, large reaction surface area and good strain accommodation.
•Porous NiCo2O4 hetero-structure arrays on nickel foam were prepared by facile hydrothermal method.•The porous NiCo2O4 hetero-structure array exhibits excellent pseudocapacitive properties.•The specific capacitance achieves a maximum of 1089 F g−1 at a current density of 2 A g−1.•The specific capacitance can still retain 1058 F g−1 (97.2% retention) after 8000 cycles.
► In this paper, we attempt to address the poor kinetics of conversion reactions, the major drawback for it, by synchronously considering optimization design of electrode configuration and ...improvement of the lattice electronic conductivity of active materials. Results suggest Co-doped NiO nanoflake arrays electrode show high capacity, good cycling performance and rate capability. These can be attributed to the synthesis effect, coming from high electrode–electrolyte contact area, direct contact between each naonflake and current collector, fast Li+ diffusion and improvement of p-type conductivity of active materials.
Co-doped NiO nanoflake arrays with a cellular-like morphology are fabricated by low temperature chemical bath deposition. As anode material for lithium ion batteries (LIBs), the array film shows a capacity of 600mAhg−1 after 50 discharge/charge cycles at low current density of 100mAg−1, and it retains 471mAhg−1 when the current density is increased to 2Ag−1. Appropriate electrode configuration possesses some unique features, including high electrode–electrolyte contact area, direct contact between each naonflake and current collector, fast Li+ diffusion. The Co2+ partially substitutes Ni3+, resulting in an increase of holes concentration, and therefore improved p-type conductivity, which is useful to reduce charge transfer resistance during the charge/discharge process. The synergetic effect of these two parts can account for the improved electrochemical performance.
► We synthesize a hierarchically porous NiO film. ► The hierarchically porous NiO film possesses large surface area (196.8
m
2
g
−1). ► A specific capacitance of 200
F
g
−1 can be obtained at a ...discharging current of 20
A. ► 87% of capacitance is retained when the current density changes from 2 to 20
A
g
−1.
A hierarchically porous NiO film on nickel foam substrate is prepared by a facile ammonia-evaporation method. The self-assembled film possesses a structure consisting of NiO triangular prisms and randomly porous NiO nanoflakes. The pseudocapacitive behaviors of the porous NiO film are investigated by cyclic voltammograms and galvanostatic charge–discharge tests in 1
M KOH. The hierarchically porous NiO film exhibits a high discharge capacitance and excellent rate capability with 232
F
g
−1, 229
F
g
−1, 213
F
g
−1 and 200
F
g
−1 at 2, 4, 10, and 20
A
g
−1, respectively. The specific capacitance of 87% is maintained from 2
A
g
−1 to 20
A
g
−1. The porous NiO film also shows rather good cycling stability and exhibits a specific capacitance of 348
F
g
−1 after 4000 cycles.
Two-dimensional (2D) layered molybdenum ditelluride (MoTe2) crystals, featuring a low energy barrier in the crystalline phase transition and a sizable band gap close to that of silicon, are rapidly ...emerging with substantial potential and promise for future nanoelectronics. It has been challenging, however, to realize n-type MoTe2 field-effect transistors (FETs), thus complementary logic, because MoTe2 FETs mainly exhibit p-type behavior. Here, we report a dopant-free method for controlling polarity of MoTe2 FETs by modifying Schottky barriers at their MoTe2–metal contacts via thermal annealing. Upon annealing, MoTe2 FETs encapsulated by hexagonal boron nitride (h-BN) are consistently changed from hole to electron conduction, displaying an on/off current ratio of 105 or higher. When the MoTe2 channel is sandwiched between top and bottom h-BN thin layers (h-BN/MoTe2/h-BN FETs), higher field-effect mobility is attained, up to 48.1 cm2 V–1 s–1 (hole) and 52.4 cm2 V–1 s–1 (electron) before and after thermal annealing, respectively. The thermally controlled FET polarity change further enables high-performance MoTe2 monolithic complementary inverters with gain as high as 36, suggesting this simple and effectual approach may lead to compelling possibilities of rationally controlling transport polarity, on demand, in atomically thin transistors with metal contacts and their 2D integrated circuits.
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