Molecular cloning and characterization of a gene encoding the proline transporter protein in common bean(Phaseolus vulgaris L.)

As a typical compatible solute, proline is accumulated in plants under environmental stresses. Proline transporter(Pro T) plays an important role in proline distribution between plant organs. Using a candidate gene approach, we cloned a c DNA sequence for Pro T from common bean(Phaseolus vulgaris L.) and designated the gene Pv Pro T. The deduced amino acid sequence of Pv Pro T showed high similarity to Bet/Pro T proteins from other leguminous plants, and the highest similarity was observed with mothbean(Vigna aconitifolia L.) Vu Pro T.Relative quantification of the m RNA level of Pv Pro T using real-time PCR analysis showed that the Pv Pro T transcript level was higher in leaves than in stems and roots of common bean plants subjected to drought and salt stress. Under 20%(w/w) PEG-6000 treatment,drought-resistant plants expressed a higher level of Pv Pro T transcripts than droughtsensitive plants. Although heterologous expression of Pv Pro T in the Escherichia coli mutant mkh13 showed that Pv Pro T exhibited uptake activities for proline and betaine, no betaine content was detected in the common bean. These findings suggest that Pv Pro T plays an important role in the transportation of proline in common bean plants exposed to drought and salt stress.

Contrasting Transport Performance of Electron-and Hole-Doped Epitaxial Graphene for Quantum Resistance Metrology

Epitaxial graphene grown on silicon carbide(Si C/graphene)is a promising solution for achieving a highprecision quantum Hall resistance standard.Previous research mainly focused on the quantum resistance metrology of n-type Si C/graphene,while a comprehensive understanding of the quantum resistance metrology behavior of graphene with different doping types is lacking.Here,we fabricated both n-and p-type Si C/graphene devices via polymer-assisted molecular adsorption and conducted systematic magneto-transport measurements in a wide parameter space of carrier density and temperature.It is demonstrated that n-type devices show greater potential for development of quantum resistance metrology compared with p-type devices,as evidenced by their higher carrier mobility,lower critical magnetic field for entering quantized Hall plateaus,and higher robustness of the quantum Hall effect against thermal degeneration.These discrepancies can be reasonably attributed to the weaker scattering from molecular dopants for n-type devices,which is further supported by the analyses on the quantum interference effect in multiple devices.These results enrich our understanding of the charged impurity on electronic transport performance of graphene and,more importantly,provide a useful reference for future development of graphene-based quantum resistance metrology.

Gene expression of vascular endothelial growth factor A and hypoxic adaptation in Tibetan pig

Background： Vascular endothelial growth factor A （VEGFA） can induce endothelial cell proliferation, promote cell migration, and inhibit apoptosis. These processes play key roles in physiological blood vessel formation and pathological angiogenesis. Methods： In this study, we examined VEGFA gene expression in the heart, liver, and kidney of Tibetan pigs （-I-P）, Yorkshire pigs that migrated to high altitudes （YH）, and Yorkshire pigs that lived at low altitudes （YL）. We used PCR and Sanger sequencing to screen for single nucleotide polymorphisms （SNPs） in 5＇-flanking DNA and exons of the VEGFA gene. Quantitative real-time PCR and western blots were used to measure expression levels and PCR products were sequenced. Results： Results showed that the VEGFA mRNA and protein expression in heart, liver and kidney of TP was higher than that in YH and YL. In addition, the mRNA sequence of the pig VEGFA gene was conserved among pig breeds, and only five SNPs were found in the 5＇-flanking region of the VEGFA gene, the allele frequency distributions of the 5 SNPs were not significantly different between the TP, Yorkshire （YL）, and Diannan small-ear （DN） pig populations. Conclusion： In conclusion, the Tibetan pig showed high tissues, which suggests that the VEGFA gene may play a levels of VEGFA gene expression in several hypoxic major functional role in hypoxic adaptation.

胡154区长4＋5油层组水淹层解释方法研究

注水开发是提高岩性油气层采收率的一种有效方法,后期井网加密调整更是为了动用剩余油,进一步提高油藏采收率的有效方法.但由于长期的注水开发,部分储层已经水淹或者严重水淹,由于注入水进入地层,导致地层水矿化度变得复杂,不同水淹层测井曲线形态呈现多样性,解释难度非常大.经过对胡154区长4＋5油层组水淹层特征研究,总结出3种水淹层解释方法：新老井电阻率对比法、测井曲线形态法、电阻率曲线重构法.2017年通过3种方法综合应用,胡154区长4＋5油层组加密调整井解释符合率达92.2%,取得了较好的应用效果.

Vapor deposition of aluminium oxide into N-rich mesoporous carbon framework as a reversible sulfur host for lithium-sulfur battery cathode

Restraining the shuttle effects of lithium polysulfides is the key to improve the cycling reversibility and stability of lithium-sulfur(Li-S)batteries for which design of robust sulfur hosts has been regarded as the most effective strategy.In this work,we report a new type of hybrid sulfur host which is composed of Al_(2)O_(3) homogenously decorated in nitrogen-rich mesoporous carbon framework(NMC-Al_(2)O_(3)).The NMC-Al_(2)O_(3) hybrid host features a poly-dispersed spherical morphology and a mesoporous configuration with high surface area and large pore volume that can accommodate a high sulfur content up to 73.5 wt.%.As a result,the fabricated NMC-Al_(2)O_(3)-S cathode exhibits all-round improvements in electrochemical properties in term of capacities(1,212 mAh·g^(-1)at 0.2 C;755 mAh·g^(-1)at 2 C),cycling charge-discharge reversibility(sustainably 100%efficiencies)and stability(1,000 cycles with only 0.023%capacity decay per cycle at 0.5 C).By contrast,the Al_(2)O_(3)-free NMC-S cathode shows both decreased capacities and rapidly descending Coulombic efficiencies during cycling.Density functional theory(DFH")calculations further reveal that the implanted Al_(2)O_(3) can greatly enhance the chemical adsorption and catalytic conversion for various lithium polysulfides and thereby effectively prevent the polysulfide shuttling and significantly improve the utilizability,reversibility and stability of sulfur cathode.

Nanocapsules of oxalate oxidase for hyperoxaluria treatment

Enzyme therapeutics have great potential for the treatment of systemic disorders such as urolithiasis and nephrocalcinosis, which are caused by the excessive accumulation of oxalate. However, exogenous enzymes have short half-lives in vivo and elicit high immunogenicity, which largely limit the therapeutic outcomes. Herein, we report a delivery strategy whereby therapeutic enzymes are encapsulated within a thin zwitterionic polymer shell to form enzyme nanocapsules. The strategy is exemplified by the encapsulation of oxalate oxidase （OxO） for the treatment of hyperoxaluria, because as-synthesized OxO nanocapsules have a prolonged blood circulation half-life and elicit reduced immunogenicity. Our design of enzyme nanocapsules that enable the systemic delivery of therapeutic enzymes can be extended to various biomedical applications.

Hierarchical Manganese Oxide/Carbon Nanocomposites for Supercapacitor Electrodes

有装载的层次毛孔结构和可控制的 MnO2 的 MnO2/carbon nanocomposites 用一个自我限制的生长方法被综合了。这被 KMnO4 的氧化还原作用反应与包含层次毛孔的牺牲的碳底层完成。唯一的毛孔结构允许 nanocomposites 的合成，悦耳的 MnO2 装载直到 83 wt.% 。nanocomposites 的特定的电容增加了， MnO2 装载；在另一方面，电气化学的阻抗光谱学测量的传导性与增加装载的 MnO2 减少了。装载的 MnO2 的优化与高特定的电容和优秀的率能力导致了 nanocomposites。这个工作提供将为应用的一个大变化便于高效的 supercapacitor 材料的设计和制造的重要基本理解。

羧基双齿结构连接二氧化钛与NH2-MIL-101(Fe):一种共轭效应引发的高效可见光光催化平台

经过数十年的深入研究,半导体光催化技术已经发展成为一种处理废水的高效技术.TiO2由于其低成本、无毒、可循环性和高稳定性成为光催化降解污染物的最有前途的半导体光催化材料之一.金属有机骨架具有较大的比表面积,可调节的孔径,较多的活性位点和稳定化学性质.将铁基金属有机骨架材料通过羧基双齿结构锚定在TiO2表面是一种增强异质结结构稳定的方法.此外,靠近锚定部分的羧基双齿结构具有较强的吸电子效应,会从Fe-MOFs中拉出电子密度并注入TiO2中.羧基双齿螯合结构可以连接供体和受体,使分子内的电荷从供体向TiO2的迁移能力增强并产生共轭效应.本文使用羧基双齿结构可控的将NH2-MIL-101(Fe)锚定到TiO2空心纳米球表面,TiO2和NH2-MIL-101(Fe)之间的共轭效应有效地提升了光生电子从NH2-MIL-101(Fe)向TiO2的转移能力.同时,引入的带尾结构缩短了复合物的带隙并提升了复合物(TiO2@NH2-MIL-101(Fe))的光催化性能.

Phosphorylcholine polymer nanocapsules prolong the circulation time and reduce the immunogenicity of therapeutic proteins

Protein therap34 wherein therapeutic proteins are delivered to treat disorders, is considered the safest and most direct approach for treating diseases. However, its applications are highly limited by the paucity of efficient strategies for delivering proteins and the rapid clearance of therapeutic proteins in vivo after their administration. Here, we demonstrate a novel strategy that can significantly prolong the circulation time of therapeutic proteins as well as minimize their immunogenicity. This is achieved by encapsulating individual protein molecules with a thin layer of crosslinked phosphorylcholine polymer that resists protein adsorption. Through extensive cellular studies, we demonstrate that the crosslinked phosphorylcholine polymer shell effectively prevents the encapsulated protein from being phagocytosed by macrophages, which play an essential role in the clearance of nanoparfides in vivo. Moreover, the polymer shell prevents the encapsulated protein from being identified by immune cells. As a result, immune responses against the therapeutic protein are effectively suppressed. This work describes a feasible method to prolong the circulation time and reduce the immunogenicity of therapeutic proteins, which may promote the development and application of novel protein therapies in the treatment of diverse diseases.

Frequency-modulated continuous waves controlled by space-time-coding metasurface with nonlinearly periodic phases

The rapid development of space-time-coding metasurfaces(STCMs)offers a new avenue to manipulate spatial electromagnetic beams,waveforms,and frequency spectra simultaneously with high efficiency.To date,most studies are primarily focused on harmonic generations and independent controls of finite-order harmonics and their spatial waves,but the manipulations of continuously temporal waveforms that include much rich frequency spectral components are still limited in both theory and experiment based on STCM.Here,we propose a theoretical framework and method to generate frequency-modulated continuous waves(FMCWs)and control their spatial propagation behaviors simultaneously via a novel STCM with nonlinearly periodic phases.Since the carrier frequency of FMCW changes with time rapidly,we can produce customized time-varying reflection phases at will by the required FMCW under the illumination of a monochromatic wave.More importantly,the propagation directions of the time-varying beams can be controlled by encoding the metasurface with different initial phase gradients.A programmable STCM prototype with a full-phase range is designed and fabricated to realize reprogrammable FMCW functions,and experimental results show good agreement with the theoretical analyses.

Synthesis of Monodisperse CexZr1-xO2 Nanocrystals and the Size-Dependent Enhancement of Their Properties

Monodisperse Ce1 ? x Zr x O2 nanocrystals 用一条简单二阶段的途径被综合了；调整使用的先锋的比率，盖住使用的代理人的数量，反应时间和温度在他们的作文，结构和尺寸上负担得起精确控制。氧存储能力的尺寸依赖者改进和氧存储和版本的动力学被观察。系统的研究被进行以便理解这些性质的尺寸依赖者改进。这个工作向重要卓见提供进合成和多部件 nanocrystals 的基本理解应用的一个大变化。

Synthesis of Protein Nano-Conjugates for Cancer Therapy

一个真核细胞的房间包含调整它的细胞的功能的几千蛋白质；交付功能的蛋白质进房间修正细胞的功能为各种各样的疾病的治疗保持大诺言，特别癌症。在这上下文， ribonuclease (RNase ) ，毁坏核糖核酸酸(RNA ) 的酶，为癌症有大潜力治疗。然而，它的治疗学的申请被无所不在的细胞内部的 RNase 禁止者被差的细胞内部的交货效率和抑制妨碍。在这工作，由设计和综合 RNase nano 结合由在 situ 原子转移基聚合(ATRP ) ，我们表明简单溶液到地址两挑战。与本国的 RNase 相比， nano 结合展览显著地提高了细胞内部的交货效率，禁止者抵抗，和 cytotoxicity 的近五倍的增加。这个工作为癌症治疗和另外的应用为治疗学的蛋白质的交货提供一个新奇平台。

Efficient Synthesis of PbTe Nanoparticle Networks

The synthesis of semiconductor nanocrystalline networks using weak capping ligands in aqueous media has been demonstrated.Carbohydrates,includingβ-cyclodextrin,D-(+)-glucose,D-glucosamine,lactobionic acid,sucrose,and starch were chosen as weak ligands to facilitate the formation of PbTe nanoparticle networks.The nanoparticle size,ranging from 5 nm to 30 nm,can be tuned by manipulating the temperature and concentration.Through a similar strategy,more complicated nanostructures including carbohydrate spheres@PbTe core-shell structures and Te@carbohydrate@PbTe multilayered submicron cables have been fabricated.This is a general approach which can be easily extended to the fabrication of other semiconductor networks,including PbSe and Bi2Te3 using carbohydrates and ethylenediaminetetraacetic acid(EDTA),respectively,as ligands.

Confined growth of Li4Ti5O12 nanoparticles in nitrogendoped mesoporous graphene fibers for high-performance lithium-ion battery anodes

Nanomaterials with electrochemical activity are always suffering from aggregations, particularly during the high-temperature synthesis processes, which will lead to decreased energy-storage performance. Here, hierarchically structured lithium titanate/nitrogen-doped porous graphene fiber nanocomposites were synthesized by using confined growth of Li4Ti5O12 （LTO） nanoparticles in nitrogen-doped mesoporous graphene fibers （NPGF）. NPGFs with uniform pore structure are used as templates for hosting LTO precursors, followed by high-temperature treatment at 800 ~C under argon （Ar）. LTO nanoparticles with size of several nanometers are successfully synthesized in the mesopores of NPGFs, forming nanostructured LTO/NPGF composite fibers. As an anode material for lithium-ion batteries, such nanocomposite architecture offers effective electron and ion transport, and robust structure. Such nanocomposites in the electrodes delivered a high reversible capacity （164 mAh.g-1 at 0.3 C）, excellent rate capability （102 mAh-g-1 at 10 C）, and long cycling stability.

Prolonging the plasma circulation of proteins by nano- encapsulation with phosphorylcholine-based polymer

Short in vivo circulation is a major hindrance to the widespread adoption of protein therapeutics. Protein nanocapsules generated by encapsulating proteins with a thin layer of phosphorylcholine-based polymer via a two-step encapsulation process exhibited significantly prolonged plasma half-life. Furthermore, by constructing nanocapsules with similar sizes but different surface charges and chemistry, we demonstrated a generic strategy for prolonging the plasma half-life of therapeutic proteins. In an in vitro experiment, four types of bovine serum albumin （BSA） nanocapsules were incubated with fetal bovine serum （FBS） in phosphate buffer saline （PBS）; the cell uptake by HeLa cells was monitored to systematically evaluate the characteristics of the surface chemistry during drculation. Single positron emission tomography-computed tomography （SPECT） was employed to allow real-time observation of the BSA nanoparticle distribution in vivo, as well as quantification of the plasma concentration after intravenous administration. This study offers a practical method for translating a broad range of proteins for clinical use.

Nitrogen-rich carbon spheres made by a continuous spraying process for high-performance supercapacitors

Supercapacitors have high power densities, high efficiencies, and long cycling lifetimes; however, to enable their wider use, their energy densities must be significantly improved. The design and synthesis of improved carbon materials with better capacitance, rate performance, and cycling stability has emerged as the main theme of supercapacitor research. Herein, we report a facile synthetic method to prepare nitrogen-rich carbon particles based on a continuous aerosol- spraying process. The method yields particles that have high surface areas, a uniform microporous structure, and are highly N-doped, resulting in a synergism that enables the construction of supercapacitors with high energy and power density for use in both aqueous and commercial organic electrolytes. Furthermore, we have used density functional theory calculations to show that the improved performance is due to the enhanced wettability and ion adsorption interactions at the carbon/electrolyte interface that result from nitrogen doping. These findings provide new insights into the role of heteroatom doping in the capacitance enhancement of carbon materials; in addition, our method offers an efficient route for large-scale production of doped carbon.

Systemic delivery of microRNA for treatment of brain ischemia

Brain ischemia is the second leading cause of death and the third leading cause of disability in the world.Systemic delivery of microRNA,a class of molecules that regulate the expression of cellular proteins associated with angiogenesis,cell growth,proliferation and differentiation,holds great promise for the treatment of brain ischemia.However,their therapeutic efficacy has been hampered by poor delivery efficiency of microRNA.We report herein a platform technology based on microRNA nanocapsules,which enables their effective delivery to the disease sites in the brain.Exemplified by microRNA-21,intravenous injection of the nanocapsules into a rat model of cerebral ischemia could effectively ameliorate the infarct volume,neurological deficit and histopathological severity.