Soliton propagation for a coupled Schrödinger equation describing Rossby waves

We study a coupled Schrödinger equation which is started from the Boussinesq equation of atmospheric gravity waves by using multiscale analysis and reduced perturbation method.For the coupled Schrödinger equation,we obtain the Manakov model of all-focusing,all-defocusing and mixed types by setting parameters value and apply the Hirota bilinear approach to provide the two-soliton and three-soliton solutions.Especially,we find that the all-defocusing type Manakov model admits bright-bright soliton solutions.Furthermore,we find that the all-defocusing type Manakov model admits bright-bright-bright soliton solutions.Therefrom,we go over how the free parameters affect the Manakov model’s allfocusing type’s two-soliton and three-soliton solutions’collision locations,propagation directions,and wave amplitudes.These findings are useful for setting a simulation scene in Rossby waves research.The answers we have found are helpful for studying physical properties of the equation in Rossby waves.

From model to alfalfa:Gene editing to obtain semidwarf and prostrate growth habits

Alfalfa(Medicago sativa L.)is a nutritious forage crop with wide ecological adaptability.The molecular breeding of alfalfa is restricted by its heterozygous tetraploid genome and the difficult genetic manipulation process.Under time and resource constraints,we applied a more convenient approach.We investigated two MtGA3ox genes,MtGA3ox1 and MtGA3ox2,of Medicago truncatula,a diploid legume model species,finding that MtGA3ox1 plays a major role in GA-regulated plant architecture.Mutation of neither gene affected nitrogenase activity.These results suggest that MtGA3ox1 can be used in semidwarf and prostrate alfalfa breeding.Based on the M.truncatula MtGA3ox1 sequence,MsGA3ox1 was cloned from alfalfa,and two knockout targets were designed.An efficient CRISPR/Cas9-based genome editing protocol was used to generate msga3ox1 mutants in alfalfa.We obtained three lines that carried mutations in all four alleles in the T0 generation.Fifteen clonal plants were vegetatively propagated from each transgenic line using shoot cuttings.The plant height and internode length of msga3ox1 null mutants were significantly decreased.The number of total lateral branches,leaf/stem ratio and crude protein content of aerial plant parts of msga3ox1 mutants were significantly increased.Thus,we obtained semi-dwarf and prostrate alfalfa by gene editing.

HMGB1 Inhibitor Effectively Alleviates Psoriasis-Like Lesions and Inflammatory Cytokines in K14-VEGF Transgenic Mice

Objective:Anti-high-mobility group box 1(HMGB1)is involved in the pathogenesis of many inflammatory and autoimmune diseases,including psoriasis.The present study aimed to investigate the therapeutic effects of HMGB1 monoclonal antibody(mAb)in keratin 14(K14)-vascular endothelial growth factor(VEGF)transgenic homozygous mice.Methods:Twelve VEGF transgenic mice were randomly divided into two groups of six mice each:the anti-HMGB1 mAb group and the immune complex(IC)mAb group.The mice underwent intraperitoneal injection of anti-HMGB1 mAb or IC mAb once every 2 days for a total of three treatments.Compare the lesions on the ears of the mice and evaluate the severity of the lesions using the baseline and clinical scores on the last day of treatment.The changes in psoriasis-like lesions,cellular infiltration of T cells,dendritic cells,and neutrophils were detected by hematoxylin-eosin staining and immunohistochemistry.The mRNA expression of the inflammatory cytokines,including interleukin(IL)-6,tumor necrosis factor-α,interferon-γ,and IL-17 in the lesions were assessed by real-time quantitative polymerase chain reaction.The number ofγδT cells in the lesions of two groups were detected by flow cytometry.Thet test was used to compare their differences.Results:The anti-HMGB1 mAb effectively ameliorated the clinical skin lesions.The clinical scores in the anti-HMGB1 mAb group were lower than those in the IC mAb group(6.00±0.52vs.10.83±0.48,P<0.001).Histopathologic changes and improvements in the K14-VEGF transgenic homozygous mice were evident after three treatments.The scores of mice in the anti-HMGB1 mAb group were significantly lower than those in the IC mAb group(3.25±0.71vs.6.95±0.83,P=0.0033).The average epidermal thickness in the anti-HMGB1 mAb group was reduced by about 45%when compared with that in the IC mAb group(32.15±7.08vs.64.69±7.93,P=0.0054).Moreover,anti-HMGB1 mAb also decreased the number of infiltrating CD3+T cells,myeloperoxidase-positive neutrophils,and CD11c+dendritic cells.The ratio of ear skinγδT cells was reduced in anti-HMGB1 mAb treated group.The mRNA expression of IL-6,tumor necrosis factor-α,interferon-γ,and IL-17 in the anti-HMGB1 mAb group were significantly reduced when compared with IC mAb group(0.36±0.070vs.1.98±0.62,P=0.0148;6.43±1.37vs.13.80±1.33,P=0.0006;2.62±0.83vs.7.77±1.32,P=0.0026;4.69±1.13vs.11.41±1.92,P=0.0054).Conclusion:HMGB1 blockade(anti-HMGB1 mAb)reduced leukocyte infiltration and suppressed inflammatory cytokine expression in this K14-VEGF transgenic mouse model,markedly reducing the severity of the psoriasis-like lesions.HMGB1 blockade might serve as a potential target for the treatment of psoriasis.

基于全息的某型喷嘴燃油雾化三维特性实验研究

采用离轴脉冲激光全息诊断技术,在发动机试车台上对某型号涡轮发动机喷嘴在常温常压及高温纯空气来流条件下的燃油雾化参数进行了实验测量,获得了雾化场空间结构特征、雾化粒子空间位置、数量分布以及索太尔平均直径分布等三维量化数据。实验结果表明,常温常压条件下,该型号喷嘴形成的雾化场呈空心圆锥体分布,雾化粒子集中分布在锥体表面,粒子直径多在60~80μm之间,随距喷嘴距离的增加,粒子直径减小且趋近一致,表现出均匀的雾化效果;喷射压力较低时,近喷嘴区域密集涡流环下游出现一个类似主流环的涡流环,随着喷射压力的增大,喷嘴附近涡流环数量减少,液膜波纹及细丝增多,下游没有观察到主流环;射流两侧的雾化结构呈现不完全对称分布。在800 K、5.5 kPa的高温纯空气来流作用的工况条件下,燃烧室内雾化粒子的平均直径减小至12μm左右,雾化质量得到明显改善。

Aqueous electrocatalytic N2 reduction under ambient conditions

Recently, the electrochemical N2 reduction reaction （NRR） in aqueous electrolytes at ambient temperature and pressure has demonstrated its unique advantages and potentials. The reactants are directly derived from gaseous N2 and water, which are naturally abundant, and NH3 production is important for fertilizers and other industrial applications. To improve the conversion yield and selectivity （mainly competing with water reduction）, electrocatalysts must be rationally designed to optimize the mass transport, chemisorption, and transduction pathways of protons and electrons. In this review, we summarize recent progress in the electrochemical NRR. Studies of electrocatalyst designs are summarized for different categories, including metal-based catalysts, metal oxide-derived catalysts, and hybrid catalysts. Strategies for enhancing the NRR performance based on the facet orientation, metal oxide interface, crystallinity, and nitrogen vacancies are presented. Additional system designs, such as lithium-nitrogen batteries, and the solvent effect are introduced. Finally, existing challenges and prospects are discussed.

Metal-Organic Framework Membranes and Membrane Reactors:Versatile Separations and Intensified Processes

Metal-organic frameworks are an emerging and fascinating category of porous solids that can be self-assembled with metal-based cations linked by organic molecules.The unique features of MOFs in porosity(or surface areas),together with their diversity for chemical components and architectures,make MOFs attractive candidates in many applications.MOF membranes represent a long-term endeavor to convert MOF crystals in the lab to potentially industry-available commodities,which,as a promising alternative to distillation,provide a bright future for energy-efficient separation technologies closely related with chemicals,the environment,and energy.The membrane reactor shows a typical intensified process strategy by combining the catalytic reaction with the membrane separation in one unit.This review highlights the recent process of MOF-based membranes and the importance of MOF-based membrane reactors in relative intensified chemical processes.

审计师声誉激励对公司税收激进行为的影响研究

选取我国A股上市公司2003年至2018年的数据为研究样本,实证检验了审计师声誉激励对上市公司税收激进行为的影响。研究发现:审计师声誉激励(事务所层面与签字审计师层面)与其客户的税收激进程度显著正相关,说明审计师在面对大客户时,更愿意帮助其掩盖税收激进行为。进一步研究表明,良好的内部控制环境和广泛的分析师关注可以有效缓解管理层以公谋私的代理问题,增强公司信息透明度,进而对审计师声誉激励与税收激进程度之间的正向关系起到一定的抑制作用。本文为审计师声誉激励与公司税收激进行为之间的关系提供了全新的经验证据,其结论为进一步强化纳税监管体系、完善审计服务市场和提高公司治理有效性提出了有益的启示。

具有膜-载体互锁型复合微结构的ZIF-L膜应用于H_(2)/CO_(2)分离

金属-有机骨架(MOF)膜在低能耗化工分离领域具有广阔应用前景.其关键在于膜的微结构设计,所面临重要挑战有:(1)如何降低膜层厚度以极大减小传质阻力;(2)如何调控膜的孔道取向以优化分子选择性传输;(3)如何强化晶界结构以最大程度减少缺陷流,进而实现高渗透率和高分离选择性.本文利用原位界面组装策略制备ZIF-L膜.通过调变配体浓度,可将膜层完全限制在载体孔隙内,形成高度取向的膜-载体互锁型复合微结构,膜表观厚度为零,充分满足了上述设计原则.ZIF-L膜的气体测试结果显示,其H_(2)/CO_(2)分离因子超过200,H_(2)渗透率达4000 GPU以上,性能位于工业应用目标区域(H_(2)渗透率>1000 GPU,H_(2)/CO_(2)分离因子>60),为迄今H_(2)/CO_(2)分离性能最优的ZIF-L膜.再者,这种具有膜-载体互锁型复合微结构的ZIF-L膜,展现出良好的机械稳定性.以硅橡胶垫反复刮擦膜表面,不会造成选择性下降.这为MOF膜的微结构设计提供了重要方向.