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转折的时代:2018年网络幻想文学阅读札记
Get PDF2018年幻想文学有诸多新象:一是随着新世代读者和写手的登场,带来更为轻松活泼的形式;二是老作家的自我挑战,部分老作家对流行的模式和套路有所反思;三是新文体和新模式的开拓,尤其是在网络社交平台的影响下,部分作品借鉴直播、聊天软件、影视剧等,进一步打破虚实界限,拓展网络文学的新形式;此外还有读者群的分化,出现多元的小众阅读趣味。在具有开拓性的创新之作外,更多的则是模式化、套路化作品,这或许是转折的另一重意义,即幻想文学乃至网络文学应从注重数量转向质量的经营,幻想文学不是虚无主义的逋逃薮,应从社会矛盾的想象性解决转向对现实问题的叩击和回应
新时代推进国家统一进程的战略蓝图
Get PDF1月2日,中共中央总书记、国家主席、中央军委主席习近平在《告台湾同胞书》发表40周年纪念会上的重要讲话,全面阐述了祖国大陆立足新时代、在民族复兴伟大征程中推进祖国和平统一的重大政策主张。习近平总书记在即将迎来中华人民共和国成立70周年的重要时刻,在《告台湾同胞书》发表40周年之际,在中国特色社会主义进入新时代、中华民族迈向伟大复兴的征程中,在国际形势
当前台湾地区“台独”组织类型研究
Get PDF当前台湾岛内的\"台独\"组织众多。本文通过对\"台独\"下定义,按照组织发展的世代、属性、主张、功能、表现形式和在\"统独\"光谱中的位置来进行了细致的划分。通过定义和类型划分的研究,力图通过对\"台独\"组织进行全面的认识,在理论上为后续研究奠定基础,在现实中为制定相关政策提供依据
非齐次不可压MHD方程的正则性与能量耗散
Get PDF本文主要研究定义在T~3上的非齐次不可压MHD方程弱解的能量局部方程;证明在Besov空间中,解的正则性足以保证总能量的平衡.本文的估计方法是Feireisl的估计方法的一个变形.国家自然科学基金(批准号:11271305和11531010)资助项
A Müntz-Collocation Spectral Method for Weakly Singular Volterra Integral Equations
Get PDFAbstract(#br)In this paper we propose and analyze a fractional Jacobi-collocation spectral method for the second kind Volterra integral equations (VIEs) with weakly singular kernel ( x - s ) - μ , 0 < μ < 1 . First we develop a family of fractional Jacobi polynomials, along with basic approximation results for some weighted projection and interpolation operators defined in suitable weighted Sobolev spaces. Then we construct an efficient fractional Jacobi-collocation spectral method for the VIEs using the zeros of the new developed fractional Jacobi polynomial. A detailed convergence analysis is carried out to derive error estimates of the numerical solution in both L ∞ - and weighted L 2 -norms. The main novelty of the paper is that the..
Weak-strong uniqueness for the Navier–Stokes–Poisson equations
Get PDFAbstract(#br)This paper is devoted to study the weak-strong uniqueness property of compressible Navier–Stokes–Poisson system. By means of relative entropy method, we prove the result that the weak solution coincides with the strong solution, emanating from the same initial data, as long as the latter exists
部分完全二部图与完全三部图的厚度关系
Get PDF图的厚度是指将该图分解为平面生成子图的最小数,它是衡量一个图可平面性的关键指标之一,研究一个图的厚度至关重要,在超大规模集成电路和网络设计中有着重要应用.在已知的一部分图类的厚度的精确值结果的基础上,研究了部分完全二部图与完全三部图的厚度关系,得到了K1,n,n+1与Kn+1,n+1、K1,n,n+2与Kn+1,n+2、K2,n,n+2与Kn+2,n+2厚度相等的结果.国家自然科学基金(11401430
平面及球面嵌入图α-定向的flip-距离
No full text为研究平面嵌入图的给定出度序列的定向问题,Felsner引入了α-定向及flip变换,并进一步证明了一个平面嵌入图的所有α-定向在flip变换下构成一个分配格.本文中给出平面嵌入图的一个α-定向可由另一个α-定向通过一系列flip变换而得到的一个充分必要条件.与之平行,证明了球面嵌入图的任意两个α-定向均可通过一系列flip变换而相互得到.最后,给出了所需最少flip变换的数目.国家自然科学基金(11471273,11561058
Interplay between Lefty and Nodal signaling is essential for the organizer and axial formation in amphioxus embryos
Get PDFAbstract(#br)The organizer is an essential signaling center required for axial formation during vertebrate embryonic development. In the basal chordate amphioxus, the dorsal blastopore lip of the gastrula has been proposed to be homologous to the vertebrate organizer. Lefty is one of the first genes to be expressed in the organizer. The present results show that Lefty overexpression abolishes the organizer; the embryos were severely ventralized and posteriorized, and failed to develop anterior and dorsal structures. In Lefty knockouts the organizer is enlarged, and anterior and dorsal structures are expanded. Different from Lefty morphants in vertebrates, amphioxus Lefty mutants also exhibited left-right defects. Inhibition of Nodal with SB505124 partially rescued the effects of Lefty loss-of-function on morphology. In addition, while SB505124 treatment blocked Lefty expression in the cleavage stages of amphioxus embryos, activation of Nodal signaling with Activin protein induced ectopic Lefty expression at these stages. These results show that the interplay between Lefty and Nodal signaling plays an essential role in the specification of the amphioxus organizer and axes
Exposure to low-level metalaxyl impacts the cardiac development and function of zebrafish embryos.
Get PDFMetalaxyl is an anilide pesticide that is widely used to control plant diseases caused by Peronosporales species. In order to study the toxic effects, zebrafish embryos were exposed to metalaxyl at nominal concentrations of 5, 50 and 500 ng/L for 72 hr, and the cardiac development and functioning of larvae were observed. The results showed that metalaxyl exposure resulted in increased rates of pericardial edema, heart hemorrhage and cardiac malformation. The distance between the sinus venosus and bulbus arteriosus, stroke volume, cardiac output and heart rate were significantly increased in larvae exposed to 50 and 500 ng/L metalaxyl compared to solvent control larvae. Significant upregulation in the transcription of tbx5, gata4 and myh6 was observed in the 50 and 500 ng/L treatments, and that of nkx2.5 and myl7 was observed in the 5, 50 and 500 ng/L groups. These disturbances may be related to cardiac developmental and functional defects in the larvae. The activity of Na+/K+-ATPase and Ca2+-ATPase was significantly increased in zebrafish embryos exposed to 500 ng/L metalaxyl, and the mRNA levels of genes related to ATPase (atp2a11, atp1b2b, and atp1a3b) (in the 50 and 500 ng/L groups) and calcium channels (cacna1ab) (in the 500 ng/L group) were significantly downregulated; these changes might be associated with heart arrhythmia and functional failure