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<p>Cell scratch test and Transwell were used to measure the migration abilities of HSVSMCs. NC = Negative control group, only control siRNA transfected; GAS5(-) = lncRNA-GAS5 knockdown group transfected with silence siRNA. <b>A:</b>Cell scratch test was used to measure the migration abilities of HSVSMCs. The results showed that the HSVSMCs have the best migration abilities in the first 24 hours. Values are mean±SE, N = 4. <b>B:</b> The migration abilities of HSVSMCs measured by Transwell. After transfected by lncRNA-GAS5 siRNA for 48 hours, the HSVSMCs were passage into the Transwell Inserts. Then 4 hours, 7 hours, 10 hours later, the migration HSVSMCs were photographed and counted, respectively. Knockdown of lncRNA-GAS5 expression promotes migration of HSVSMCs. Optical microscope images under 200x magnification. <b>C:</b> The migration abilities of HSVSMCs were reflected indirectly by the new migration cells counting with Transwell. Silencing of lncRNA-GAS5 expression increses migration ability of HSVSMCs. Values are mean±SE, N = 10; *, P<0.05.</p

WENO Computations and Pattern Stability

There are two separated parts of my thesis. The first part is about how to design robust unstructured weighted essentially non-oscillatory (WENO) schemes. The WENO schemes are a popular class of high order numerical methods for hyperbolic partial differential equations (PDEs). A major difficulty for unstructured WENO is how to design a robust WENO reconstruction procedure to deal with distorted local mesh geometries or degenerate cases when the mesh quality varies for complex domain geometry. We combine two different WENO reconstruction approaches to achieve a robust unstructured finite volume WENO reconstruction on complex mesh geometries. Numerical examples including both scalar and system cases are given to demonstrate stability and accuracy of the scheme. The second part is about computational biology. We studied the pattern solutions of several mathematical models, chematical cell movement, Zebrafish Dorsalventral patterning and tumor angiogenesis. The detailed dynamics, pattern structures and robustness of the nonlinear reaction-diffusion model of chemotactic cell movements [89] are discussed using high resolution numerical simulations. We show that the model can form network patterns similar to early blood vessel structures seen experimentally. The model solutions do not blow up in finite time, a property of other chemotaxis cell movement models. The reaction-diffusion system modeling the dorsal-ventral patterning during the zebrafish embryo development, developed in [128] has multiple steady state solutions. Seven steady state solutions are found by discretizing the boundary value problem using a finite difference scheme and solving the resulting polynomial system using algorithms from numerical algebraic geometry. The stability of each of these steady state solutions is studied by mathematical analysis and numerical simulations via a time marching approach. The results show that three of the seven steady state solutions are stable and the location of the organizer of a zebrafish embryo determines which stable steady state pattern the multi-stability system converges to. Numerical simulations also show that the system is robust with respect to the change of the organizer size. Similar approaches are applied to a more complicate free boundary problem on tumor growth. </p

Covalent/non-covalent recognition strategies for visualized sensing of trace organic amines

Precise, timely and visualized recognition of trace organic amines is of great significance for safeguarding human health, ecological environment, public security, etc., especially crucial for adopting appropriate disposition measures. For this purpose, great efforts have been made to finely design the optical probe structure which is the core of the specific recognition. Here, we proposed the recognition strategies based on either covalent nor non-covalent interactions to achieve the detection towards the targets with primary amine, tryptamine and ethylenediamine [1-2]. These sensing strategies exhibited ppb/nM level sensitivity, specific recognition without disturbance to the potential interferents, as well as rapid optical response within 1 s. Furthermore, by integrating the optical probe with the portable sensing chip, the sensing performances were verified to be capable for detecting the trace analytes in the complicated practical scenarios, providing a valuable reference for designing.</p

Engineering of plasmonic nanostructures for surface-enhanced Raman spectroscopic applications in liquid biopsy analysis

Diagnosis of cancer at early stages can significantly increase a patient’s survival rate and improve their quality of life. Tissue biopsy, considered as the clinically validated gold standard approach, has been applied to diagnose diseases and cancers. However, tissue biopsy faces a series of issues for wide practical utilizations, such as its invasive nature with associated risk and the difficulty of repeated sampling. Recently, liquid biopsy as an alternative candidate for clinical applications (e.g., early diagnosis) has been increasingly valued because it offers a non-invasive cancer screening option without having to obtain tumor tissue. It can be utilized in real-time to characterize the genetic landscape of cancerous lesions by analyzing specific disease-associated biomarkers from body fluids. Extensively studied biomarkers include circulating tumor-derived cells (CTCs), extracellular vesicles (EVs), circulating tumor nucleic acids (ctNAs, e.g., ctDNA, ctRNA) and proteins (e.g., cytokines). Nevertheless, the low levels of these circulating biomarkers against the background of plentiful non-targeted biomaterials pose technical challenges to traditional tools for accurate characterization and quantification. Therefore, there is an urgent demand to develop highly sensitive and specific approaches for probing the biomarkers of interest in a simple and rapid manner.  The overall aim of this thesis is to utilize surface-enhanced Raman scattering (SERS) spectroscopy as the main technique for detecting liquid biopsy biomarkers. The superior features of SERS include ultrasensitivity, high specificity, multiplexing capability, accessibility of molecular structure information, and photostability, which render it an ideal candidate for trace analysis and multi-component profiling.  Herein, to achieve highly sensitive and reliable SERS responses, the effort was first put into engineering novel nanostructures with controlled size, morphology, composition and surface charge, and exploring how these features influence SERS signal quality. Four types of nanostructures were rationally designed, synthesized and characterized by transmission electron microscopy (TEM), dynamic light scattering, UV-visible spectroscopy (UV-vis) and SERS. The optimal positively-charged nanostar with the highest SERS enhancement was considered the appropriate substrate for the analysis of negatively-charged targets.  We used positive nanostars to establish an analysis platform for intrinsically screening negatively charged small DNAs (e.g., the mutant BRAF V600E gene type). By integrating direct SERS measurement with polymerase chain reaction (PCR) and a statistical analysis method (principal component analysis-linear discriminate analysis, PCA-LDA), the mutant V600E gene was detected and discriminated from BRAF wild type (WT) gene in both cell line and human plasma samples. This demonstrates that a PCR/direct SERS strategy is capable to ultrasensitively and accurately detect DNA mutations in clinical application.  Crossing from a single biomolecule (a mutant DNA) to a macromolecule assembly, we applied the direct SERS strategy to analyze negatively-charged tumor-derived EVs. EVs represent a snapshot of the biocomponents of their parental cells. A combination of spectroscopic methods, including SERS, UV-vis, fluorescence excitation/emission and atomic force microscope-infrared spectroscopy (AFM-IR), was employed to characterize cancerous EVs. Their molecular profile based on different experimental variables (e.g., EV origin, isolation approach, and isolation batch) was explored via SERS and PCA-LDA discrimination. This assay delivers important information on EV spectroscopic profiling and arouses concerns on corresponding variations generated from different experimental settings.  As a direct SERS strategy cannot specifically aim at a target analyte and requires sample pre-treatment, we developed a specific indirect SERS approach by means of an antibody specific targeted towards a target molecule. We applied this approach to evaluate two disease-associated cytokines. This analysis was performed on a multi-layered fibrous polymer membrane using anionic, citrate-coated, spherical gold nanoparticle as the SERS substrate. This duplex sensing assay exhibited high sensitivity, great specificity and low cross-activity when two target cytokines were concurrently detected in phosphate-buffered saline and human serum, indicating its promising analysis capability for clinical samples.  One of the issues with nanoparticles in assays is their poor stability. We, therefore, encapsulated the negatively charged nanostars within a protective silica shell to improve their stability and functionalization capability. The synthesis and silica-encapsulation were optimized for better stability in high ionic strength environment. The silica encapsulated nanostars were then used as SERS nanotags to detect cancerous EVs. Their improved stability compared to the bare nanostars implies that the silica shell coating protects nanostars from the environmental triggers and the coated nanostars are qualified to be used to analyze liquid biopsy biomarkers from a complex biological sample.  In summary, this thesis re orts the development and application of a series of nano article SERS-based strategies to analyze biomarkers in liquid bio sies. These strategies offer more choices and information for real clinical application with desirable sensitivity and specificity. Surface charge-tunable nanostars have been found to play a critical role in SERS enhancement and its encapsulation within a silica shell achieved better stability for potential clinical applications. The proof-of-concept demonstrations of this thesis open the way to developing clinically relevant nanomaterial-based assay systems for circulating biomarkers analysis in liquid biopsy.</p

data

Scientific and practical identification and analysis of the differences in the spatial structure of metropolitan areas are of great significance to the long-term development of metropolitan areas and urban agglomerations. Because the current research focuses more on the external spatial structure of the metropolitan area and less on the internal spatial differences, this study is based on remote sensing data, POI data, and road vector data combined with a spatial clustering algorithm with location constraints. Multi-level analysis of spatial clustering and differences within the circle. Theresearch results show that compared with the traditional algorithm, spatial clustering with location constraints can identify the group structure within the metropolitan area to a large extent. At the same time, the single-factor and multi- factorclustering results show that the Changsha-Zhuzhou-Xiangtan metropolitan area currently has large internal spatial differences; Except for Changsha, Zhuzhou, and Xiangtan core urban areas, no apparent cluster structure has been formed. This study can well reflect the current heterogeneity of the internal spatial structure of the Chang-Zhu-Tan metropolitan area and provide a solid reference for the future developmentof the metropolitan area</p

Effects of Interfacial Termination, Oxidation, and Film Thickness on the Magnetic Anisotropy in Mn_2.25Co_0.75Ga_0.5Sn_0.5/MgO Heterostructures

Perpendicular magnetic anisotropy (PMA) is a determining factor for the realization of nonvolatile information storage devices with high efficiency and thermal stability. In this work, a new spin gapless semiconductor Mn2.25Co0.75Ga0.5Sn0.5 Heusler alloy with an inter-spin zero gap was first designed theoretically. The Mn2.25Co0.75Ga0.5Sn0.5 bulk was prepared successfully in experiment. The effects of interfacial termination, oxidation, and film thickness on the magnetic anisotropy of Mn2.25Co0.75Ga0.5Sn0.5/MgO (MCGS/MgO) heterostructures are investigated systematically by first-principles calculations. The results show that all the Mn­(A)­Mn­(C)­GaSn-, Mn­(A)­Mn­(C)­CoGaSn-, Mn­(B)­GaSnI-, and Mn­(B)­GaSnII-terminated MCGS/MgO heterostructures (called as AC1, AC2, BD1, and BD2 models, respectively) present PMA, which mainly derives from the interfacial and surficial MCGS layers. Furthermore, the PMA of MCGS/MgO heterostructures can be preserved in a large range of interfacial oxidization (up to ±50%). With MCGS thickness increasing from 5 to 16 monolayers, the PMA of MCGS/MgO heterostructures with an AC-type surface decreases significantly. However, the PMA of BD-type surface models is relatively robust to the thickness of the MCGS layer, and the magnetic anisotropy always points to the out-of-plane direction. Therefore, MCGS Heusler alloy is a new promising spin gapless semiconductor candidate for spintronics applications. The robust and tunable PMA in MCGS/MgO heterostructures offers the possibility for developing nonvolatile data memory devices

Table_1_Effects of Basic Psychological Needs on Resilience: A Human Agency Model.DOCX

Academic resilience refers to the ability to recover and achieve high academic outcomes despite environmental adversity in the academic setting. At the same time, self-determination theory (SDT) offers a human agency model to understand individuals' autonomy to achieve in various fields. The present longitudinal study explored the factors influencing resilience from the analytical framework of SDT to investigate how basic psychological needs strengthen students' resilience. A mediation model was proposed that resilience may mediate the relationship between basic psychological needs and academic performance. The results from 450 10th grade Chinese students showed that three basic psychological needs (i.e., autonomy, competence, and relatedness) facilitate academic resilience; academic resilience thus increases subsequent academic performance after controlling for previous test scores.</p

Super-resolution atomic microscopy using orbit angular momentum laser with temporal modulation

In this paper we propose a dark-state-based trapping strategy to break the optical diffraction limit for microscopy. We utilize a spatially dependent coupling field and a probe laser field with temporal and spatial modulation to interact with three-level atoms. The temporal modulation allows us to reduce the full width at half maximum (FWHM) of point spread function, and the spatial modulation help us obtain better spatial resolution than Gaussian beam. In addition, we also propose a proof-of-principle experiment protocol and discuss its feasibility

C–C Stretching Raman Spectra and Stabilities of Hydrocarbon Molecules in Natural Gas Hydrates: A Quantum Chemical Study

The presence of specific hydrocarbon gas molecules in various types of water cavities in natural gas hydrates (NGHs) are governed by the relative stabilities of these encapsulated guest molecule–water cavity combinations. Using molecular quantum chemical dispersion-corrected hybrid density functional computations, the interaction (Δ<i>E</i>_{host<i>‑</i>–guest}) and cohesive energies (Δ<i>E</i>_coh), enthalpies, and Gibbs free energies for the complexes of host water cages and hydrocarbon guest molecules are calculated at the ωB97X-D/6-311++G­(2d,2p) level of theory. The zero-point energy effect of Δ<i>E</i>_host–guest and Δ<i>E</i>_coh is found to be quite substantial. The energetically optimal host–guest combinations for seven hydrocarbon gas molecules (CH₄, C₂H₆, C₃H₆, C₃H₈, C₄H₈, i-C₄H₁₀, and <i>n</i>-C₄H₁₀) and various water cavities (D, ID, T, P, H, and I) in NGHs are found to be CH₄@D, C₂H₆@T, C₃H₆@T, C₃H₈@T, C₄H₈@T/P/H, i-C₄H₁₀@H, and <i>n</i>-C₄H₁₀@H, as the largest cohesive energy magnitudes will be obtained with these host–guest combinations. The stabilities of various water cavities enclosing hydrocarbon molecules are evaluated from the computed cohesive Gibbs free energies: CH₄ prefers to be trapped in a ID cage; C₂H₆ prefer T cages; C₃H₆ and C₃H₈ prefer T and H cages; C₄H₈ and i-C₄H₁₀ prefer H cages; and <i>n</i>-C₄H₁₀ prefer I cages. The vibrational frequencies and Raman intensities of the C–C stretching vibrational modes for these seven hydrocarbon molecules enclosed in each water cavity are computed. A blue shift results after the guest molecule is trapped from gas phase into various water cages due to the host–guest interactions between the water cage and hydrocarbon molecule. The frequency shifts to the red as the radius of water cages increases. The model calculations support the view that C–C stretching vibrations of hydrocarbon molecules in the water cavities can be used as a tool to identify the types of crystal phases and guest molecules in NGHs

A theoretical framework for the Hamiltonian of angular momentum optomechanical system

Photon carries linear momentum and angular momentum simultaneously. Within the light-matter interaction process, exchange of linear momentum results in optical forces, whereas exchange of angular momentum leads to optical torques. Use of optical forces (light pressure or damping) have been long and wide in quantum optomechanics, however, those of optical torque and optical angular momentum are not. Here we propose a theoretical framework based on optical angular momentum and optical torques to derive the Hamiltonians of cavity orbital and spin angular momentum optomechanical systems, respectively. Moreover, based on the method, we successfully obtain the Hamiltonian of the complex angular momentum optomechanical systems consisting of micro-cavity and several torsional oscillators, whose reflection coefficients are non-unit. Our results indicate the general applicability of our theoretical framework for the Hamiltonian of angular momentum optomechanical systems and extend the research scope of quantum optomechanics