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At present, the level of health literacy, social support, and care ability of dementia caregivers is not very high. Therefore, the purpose of this study was to construct a structural equation model to explore the relationship between health literacy, social support, and the care ability of dementia caregivers. It is hoped that the study will provide a theoretical basis for future intervention. We recruited 225 dementia patients and their caregivers from August 2018 to June 2019 at the Department of Geriatrics and Neurology. We issued a health literacy questionnaire, social support scale, and a care ability questionnaire. Statistical analyses were performed using SPSS 19.0 and SPSS Amos 23.0. The mean scores for health literacy, social support, and care ability were 13.93±4.18, 34.64±6.42, and 44.44±9.31, respectively. Health literacy was directly related to social support (path coefficient = 0.454). Social support was directly related to care ability (path coefficient = 0.293). Furthermore, health literacy was directly related to care ability (path coefficient = 0.561), while health literacy had indirect associations with care ability via social support (path coefficient = 0.133). This study showed that improving the health literacy of caregivers effectively improved their care ability, and that social support was important for the link between health literacy and care ability. Medical staff and family members can provide appropriate health education and social support according to the characteristics of caregivers to improve the care ability of caregivers, improve the quality of life of patients, and delay the disease process.

As one of the most important topics in control theory, robust stability for the systems plays a key role in many areas of science and industry. This paper discusses the robust stochastic stability ...

This paper investigates the problem of stochastic Cohen–Grossberg neural networks driven by G-Brownian motion (G-SCGNNs, in short). We establish the exponential synchronization of G-SCGNNs by applying inequality technique, kth vertex-G-Lyapunov functions, graph-theory and state feedback control technique. A concrete example is given to verify the obtained theory.

In this paper, we consider a class of impulsive stochastic differential equations driven by G-Brownian motion (IGSDEs, in short). In particular, we study the exponentially and quasi sure exponentia...

This paper studies the asymptotic behavior of the mild solution for a class of perturbed impulsive neutral stochastic functional differential equations driven by fractional Brownian motion in Hilbert space. We establish the conditions under which the mild solutions of perturbed impulsive neutral stochastic functional differential equation and the unperturbed one are close on finite time interval when the perturbation tends to zero. Moreover, we show the result holds on time interval whose length tends to infinity as the perturbation tends to zero. As an application, the asymptotic behavior of the mild solution for a class of perturbed impulsive neutral stochastic partial differential equations driven by fractional Brownian motion in Hilbert space is proposed to show the feasibility of the obtained result.

As one of the important hybrid models, stochastic fluid models (SFMs, in short) have many applications. In this work, we discuss a class of SFMs modulated by Markovian chain with lower and upper jumps, where the fluid level has a positive upper bound and a lower bound zero. The joint limiting distribution of the buffer level and the environment state is expressed by a series of differential equations. An example is give to illustrate the theory obtained.

Guanine-rich nucleic acid sequences have a high propensity to adopt non-B DNA secondary structures like G-quadruplexes. Sequences that could potentially form G-quadruplexes are widespread throughout the genome and found to be more prominent in biologically critical regions. They may play biological significant roles in telomere maintenance, as well as regulation of gene transcription, replication and recombination. G-quadruplex DNA is highly polymorphic. The study of G-quadruplex structures has attracted intense interests in the field of potential therapeutic targeting in human cancers. Structural uniqueness of G-quadruplex DNA can serve as specific recognition site for G-quadruplex interactive compounds. In Chapter 3, the structure of four-repeat Giardia telomeric sequence d[TAGGG(TAGGG)3], which differs from the human counterpart d[TAGGG(TTAGGG)3] only by one T deletion within the non-G linker in each repeat, was solved by NMR to explore the effect of loop length and sequence on the folding topology of G-quadruplexes. Two different intramolecular G-quadruplexes were found to coexist and interconvert in K+ solution. Recurrence of several structural elements in the observed structures suggests a “cut and paste” principle for the design and prediction of G-quadruplex topologies, for which different elements could be extracted from one G-quadruplex and inserted into another. The unique properties of G-quadruplex DNA compared to duplex DNA make them amenable for development of nanomaterials. In Chapter 4, Self-assembly of supramolecular G-wires, grown from the oligonucleotide d(GGGGTTGGGG), on graphene sheets were investigated. Atomic force microscope (AFM) and micro-Raman mappin results demonstrate for the first time that G-wires are well-ordered and preferentially oriented along the armchair direction of graphene. Such assembly could be further exploited for the development of graphene-based molecular device and biosensor. It can be envisioned that the development of the understanding of the thermodynamic properties and structural features of G-quadruplex DNA will endow new capabilities for structural nucleic acid nanotechnology. DOCTOR OF PHILOSOPHY (SPMS)

In this paper, we prove the existence and uniqueness of a solution for a class of multi-valued stochastic differential equations driven by G-Brownian motion (MSDEG) by means of the Yosida approximation method. Moreover, we set up an optimality principle of stochastic control problem and prove the value function of the control problem is the unique viscosity solution of a class of nonlinear partial differential variational inequalities.

In this paper, we establish the $p$-th moment exponential stability and quasi sure exponential stability of the solutions to impulsive stochastic differential equations driven by $G$-Brownian motion (IGSDEs in short) by means of $G$-Lyapunov function method. An example is presented to illustrate the efficiency of the obtained results.

In this paper, we prove the existence and uniqueness of a solution for a class of backward stochastic differential equations driven by G-Brownian motion with subdifferential operator by means of the Moreau–Yosida approximation method. Moreover, we give a probabilistic interpretation for the viscosity solutions of a kind of nonlinear variational inequalities. Copyright © 2017 John Wiley & Sons, Ltd.

This paper is concerned with p-moment stability of solutions to stochastic differential equations driven by G-Brownian motion (GSDEs) by means of the Lyapunov function and the Ito formula. An example is given to illustrate the effectiveness of the obtained results.

In this work, we discuss a kind of pantograph stochastic functional differential equations driven by G-Brownian motion (G-PSDEs, in short). When the coefficients satisfy local Lipschitz and generalized Lyapunov conditions, we establish existence, uniqueness, asymptotic boundedness and exponential stability of the solution for G-PSDEs.

In this note, we prove the existence and uniqueness of the solution for a class of reflected backward stochastic differential equations (RBSDEs in short) related to the subdifferential operator of a lower semi-continuous convex function, driven by Teugels martingales associated with a Levy process. Some known results are generalized and improved.

In this note, we prove the existence and uniqueness of a solution to stochastic differential equations driven by G-Brownian motion (GSDEs, for short) under global Caratheodory conditions by means of the successive approximation.

This paper deals with the controllability of a class of impulsive neutral stochastic functional differential inclusions with infinite delay in an abstract space. Sufficient conditions for the controllability are derived with the help of the fixed point theorem for discontinuous multi-valued operators due to Dhage. An example is provided to illustrate the obtained theory.

In this paper, we prove the existence of mild solutions for a class of impulsive neutral stochastic functional integro-differential equations with infinite delays in an abstract space by means of the Krasnoselskii-Schaefer type fixed point theorem.

In this paper, we prove the existence and uniqueness of the solution to a class of doubly perturbed neutral stochastic functional equations (DPNSFEs in short) under some non-Lipschitz conditions. The solution is constructed by successive approximation. Furthermore, we give the continuous dependence of the solution on the initial value by means of the corollary of Bihari inequality.

In this paper, a new class of generalized backward doubly stochastic differential equations (GBDSDEs in short) driven by Teugels martingales associated with Levy process and the integral with respect to an adapted continuous increasing process is investigated. We obtain the existence and uniqueness of solutions to these equations. A probabilistic interpretation for solutions to a class of stochastic partial differential integral equations (PDIEs in short) with a nonlinear Neumann boundary condition is given.

In this paper, we establish the existence and uniqueness of mild solutions for a class of semilinear integro-differential equations of fractional order with nonlocal initial conditions and delays in α-norm. And the main tool is the fixed point theorem due to Sadovskii. Some known results are generalized.

In this paper, a new class of backward doubly stochastic differential equations driven by Teugels martingales associated with a Lévy process satisfying some moment condition and an independent Brownian motion is investigated. We obtain the existence and uniqueness of solutions to these equations. A probabilistic interpretation for solutions to a class of stochastic partial differential integral equations is given.

In this paper, NaYF 4 nanocrystals and NH 4 Y 3 F 10 sub-microcrystals were prepared using a polyol method. After being annealed, NH 4 Y 3 F 10 can convert into YF 3 , which is a very efficient host matrix for upconversion. The structures of obtained NaYF 4 , NH 4 Y 3 F 10 and YF 3 samples are pure cubic phase, a mixture of cubic and hexagonal phase and pure orthorhombic phase, respectively. The size of obtained NaYF 4 nanocrystals is about 20 nm, and those of NH 4 Y 3 F 10 and YF 3 sub-microcrystals are both about 200 nm. When co-doped with Er 3+ and Yb 3+ , NaYF 4 and YF 3 samples can emit bright light under 978 nm excitation. Upconversion mechanisms in Yb 3+ /Er 3+ co-doped NaYF 4 and YF 3 samples were discussed.

The ZnO@ZnWO4:Eu3+ core–shell composites were prepared by a two-step hydrothermal method and the photoluminescence properties of the composites were studied in contrast to the corresponding hexagonal ZnO and monoclinic ZnWO4: Eu3+ nanocrystals prepared by the one-step hydrothermal method. The results demonstrate that in the nanocomposites the Eu3+ ions in the ZnWO4 phase occupy two symmetry sites, one a well-crystalline inner site and one a disordered surface site; while in the ZnWO4: Eu3+ nanocrystals, the local environments surrounding Eu3+ ions are relatively disordered for both the inner and the surface sites. This indicates that in the composites, the crystallinity of the ZnWO4 becomes better, which have positive influence on the improvement of photoluminescence. The temperature stabilities for both the emissions of ZnO and Eu3+ ions are improved in contrast to the pure ZnO or ZnWO4:Eu3+ nanocrystals.

In this paper, TiO 2 :Sm 3+ (0.75 mol%) nanoparticles doped with different amounts of Br − were prepared by an improved sol–gel method and were characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), VG ESCALAB MKIIX-ray photoelectron spectrometer (XPS) and ultraviolet–visible diffuse reflectance spectroscopy (UV–vis DRS). Their photoluminescence (PL) properties were investigated at room temperature. The emissions of 4 G 5/2 – 6 H J ( J =5/2, 7/2, 9/2) transitions of Sm 3+ ions were observed under the excitation wavelength at 350 nm and the emission intensity depended strongly on the doping amount of Br − . TiO 2 :Sm 3+ (0.75 mol%) nanoparticles doped with 1 mol% of Br − calcined at 700 °C exhibit highest intensity of luminescence, which is nearly three times than the undoped one. The mechanism of photoluminescence in the co-doped system was discussed.

In this work, the luminescence properties of samarium ions-doped titanium dioxide prepared by the sol–gel process were studied. A strong orange red emission (4G5/2−6H7/2 (orange) and 4G5/2–6H9/2 (red)) ascribed to the electron transitions in 4f5 configuration of Sm3+ ions was observed upon excitation into TiO2 host. The energy transfer from TiO2 to Sm3+ was verified and the relevant mechanism was discussed. In addition, the impacts of metal ion codopants upon the TiO2:Sm3+ luminescence properties were studied. The results indicated that the central excitation band shifted to blue in the bismuth-codoped materials (0.5–4% in molar ratio), while it shifted to red in the zirconium-codoped materials. Such materials may find applications in white light-emission diode (LED) and tunable solid lasers.

We report on a novel luminescent phenomenon in Gd2O2S : Er,Yb prepared by a solid-state reaction. After irradiation at 980 nm, the afterglow emission of Er 3+ is observed. X-ray diffraction, photoluminescent emission, long-lasting phosphorescence emission and decay curves were used to characterize the phosphor. It is found that the afterglow is improved with the co-doping of Ti 4+ and Mg 2+ . Also the upconversion luminescent spectrum of Er 3+ is changed. We ascribe this phenomenon to the change in the environment of activator ions. The phosphorescence properties of the sample are researched in detail. Due to the dependence of afterglow intensities on different irradiative powers, a possible two-step-absorption upconversion long-lasting phosphorescence mechanism is proposed. This kind of mechanism may overcome the shortcomings of the long persistent phosphors which are used for UV irradiation.

In this paper, we deal with reflected backward stochastic differential equations driven by Teugels martingales associated with L e ´vy process satisfying some moment condition and an independent Brownian motion. We derive the existence and uniqueness of solutions for these equations under Lipschitz condition on the coefficient via Snell envelope and the fixed point theorem.