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关键词： Regularity   pseudo eigenfunctions   non-uniformly weighted Sobolev spaces  

摘要： We investigate a spectral Galerkin method for the two-dimensional fractional diffusion-reaction equations on a disk. We first prove regularity estimates of solutions in the weighted Sobolev space. Then we obtain optimal convergence orders of a spectral Galerkin method for the fractional diffusion-reaction equations in the L-2 and energy norm. We present numerical results to verify the theoretical analysis.

关键词： 量子力学  

ISBN: (纸本)9787311060411

摘要： 《量子力学》在基本原理和典型定态问题的叙述上比较详细，主要是希望能使读者对基本概念、基本原理有较全面和深入的理解。作者把自己在长期的教学中总结出来的学生容易接受、教师容易讲解的一些方法融入了教材，使得课程内容更易教、易学。《量子力学》可作为理工类各专业量子力学课程的教材，也可供其他专业和社会读者阅读。

关键词： exotic atom   relativistic mechanics  

摘要： Quantum solutions of the classical equation of relativistic mechanics have been found. A synthesis of classical and quantum physics can become a basic formalism for a second quantum revolution since the existence of quantum solutions of all of the equations of classical physics implies that macroscopic bodies, both of nonliving and living matter, under certain conditions can be quantum objects. This new direction of physics can find application in the development of nature-like technologies.

关键词： Nehari manifold   Variational method   Non-local Laplacian operators   Concentration–   compactness principle  

摘要： We deal with the existence and multiplicity of solutions for a non-local fractional system involving combined critical non-linearities. Some existence results are obtained by splitting the Nehari manifold and applying the Mountain-Pass theorem of Ambrosetti and Rabinowitz.

关键词： Brucellosis   Infectious disease modelling   Force of infection   Basic reproductive number  

摘要： Brucellosis is endemic in Tanzania. A cross-sectional study was conducted at 17 cattle farms in agro-pastoral areas in Tanzania to identify risk factors associated with the within-farm prevalence of bovine brucellosis and to quantitatively assess the infection dynamics through disease modelling. Cattle blood sampling and interviews with farmers using a structured questionnaire were conducted. A total of 673 serum samples were screened using the Rose-Bengal plate test (RBPT), and sero-positivity of RBPT-positive samples was confirmed using a competitive enzyme-linked immunosorbent assay. Zero-inflated binomial regression was performed for univariable and multivariable risk factor analyses of within-farm prevalence. Several susceptible-infectious (SI) models were compared based on deviance information criteria, and age-dependent force of infection (FOI) was measured using age-specific prevalence data for the 10 infection-positive farms. Using the diagnoses of cows on the 17 farms, the basic reproduction number, R0, was also calculated. The farm-level prevalence and animal-level adjusted prevalence were 58.8 % (10/17, 95 % confidence interval: 33.5-80.6 %) and 7.0 % (28/673, 95 % credible interval: 5.7-8.4 %), respectively. The risk factor for high within-farm prevalence was introduction of cattle from other herds. A mathematical model with constant FOI showed the annual probability of infection as 1.4 % (95 % credible interval: 1.0 %-2.0 %). The R0 was 1.07. The constant FOI could have been due to the predominant mode of infection being transmission of Brucella from contaminated aborted materials during grazing. Direct purchase of infected cattle could facilitate efficient transmission between susceptible animals through abortion.

关键词： Quantum dots   Vertical cavity surface emitting laser   Nonlinear dynamical system   Bifurcation map  

摘要： A symmetric model based on optically pumped quantum dot (QD) spin-polarized vertical cavity surface emitting lasers (spin-VCSELs) subject to mutual coupling is proposed. Compared with the conventional solitary model, more plentiful dynamical regimes associated with different dynamical regions are displayed visually by numerous bifurcation maps, and the detailed direct numerical simulations accurately reveal the dependence of dynamical behavior on external and internal parameters through introducing mutual coupling scheme. We then find that the roles played by the mutual coupling strength and delay time are remarkably significant in intensifying the regime of complex dynamical oscillation. Beyond that, the crucial effects of capture rate, gain parameter, linewidth enhancement factor and frequency detuning on determining the evolvement of dynamical behavior in the mutually coupled QD spin-VCSELs model are shown evidently in the plane of the optical pump intensity and polarization. Through a comprehensive investigation of the dynamical behavior dependent on key parameters, the dynamical mechanism expressed in the current model can be adjusted and even controlled well. Therefore, the involved efforts are enlightening and foresighted to promote a deeply research in the field of QD lasers-based expansion.

关键词： Quantum dots   Black Phosphorus Quantum Dots   Photodynamic Therapy   pH-response  

摘要： Black phosphorus quantum dots(BPQDs) have shown a good application prospect in the field of tumor therapy due to their photoelectric effect and good biodegradability. Due to the active endocytosis and fast metabolic efficiency of tumor cells, BPQDs are easy to be absorbed by tumor cells. However, this does not guarantee that BPQDs will be completely targeted to tumor cells, and normal cells will also absorb BPQDs. Because the cell membrane is negatively charged, BPQDs are also negatively charged and are not easily absorbed by cells under the action of electrostatic repulsion. Surface pegylation is the most common modification method of black phosphorus at present. However, surface pegylation can reduce the uptake of BPQDs by tumor cells. Positive PEG is also easy to be recognized and swallowed by the reticuloendothelial system. The inherent instability and poor tumor targeting of BPQDs under physiological conditions limit further research and clinical application. For this purpose, we selected cationic polymer polyethylenimine (PEI) to modify BPQDs and then added RGD peptides targeting tumor cells. An outer layer of negatively charged PEG+DMMA makes the nanosystem more stable . In the acidic environment of the tumor, the PEG layer has a charge reversal, and the positively charged PEI and the RGD polypeptide BPQDs targeted by the tumor cells are released into the tumor cells. It provides a new method for efficiently and accurately transporting BPQDs, a novel photosensitive nanomaterial, into tumor cells for photodynamic therapy.

关键词： 游泳教学   表象训练   心理训练   实践路径  

摘要： 表象训练是一种科学合理、切实可行的心理训练方法,我国引入该理念后,就将其广泛普及应用到体育教育领域当中,并且取得了不俗的成绩.本文主要阐述表象训练理论的基本内涵,并在游泳教学当中对其进行充分运用,明确其实际应用价值,同时从心理训练、游泳动作基础以及技术动作训练等诸多层面出发,对表象训练方法具备的核心价值进行深入探究,提出切实高效、科学可行的方案,从而制定出更加有效的实践策略,让游泳教学和表象训练融合的更加紧密,促进游泳教学的长效发展.以供参考和借鉴.

关键词： cytotoxicity   hemithioindigo   microtubule dynamics   photopharmacology   photoswitch  

摘要： We report the first cellular application of the emerging near-quantitative photoswitch pyrrole hemithioindigo, by rationally designing photopharmaceutical PHTub inhibitors of the cytoskeletal protein tubulin. PHTub s allow simultaneous visible-light imaging and photoswitching in live cells, delivering cell-precise photomodulation of microtubule dynamics, and photocontrol over cell cycle progression and cell death. This is the first acute use of a hemithioindigo photopharmaceutical for high-spatiotemporal-resolution biological control in live cells. It additionally demonstrates the utility of near-quantitative photoswitches, by enabling a dark-active design to overcome residual background activity during cellular photopatterning. This work opens up new horizons for high-precision microtubule research using PHTub s and shows the cellular applicability of pyrrole hemithioindigo as a valuable scaffold for photocontrol of a range of other biological targets.

关键词： Quantum chemistry  

摘要： Ever since the dawn of quantum mechanics, it has been recognized that molecular systems are intrinsically quantum and should be treated as such if a quantitativ