Numerical reconstruction of the spatial component in the source term of a time-fractional diffusion equation

In this article, we are concerned with the analysis on the numerical reconstruction of the spatial component in the source term of a time-fractional diffusion equation. This ill-posed problem is solved through a stabilized nonlinear minimization system by an appropriately selected Tikhonov regularization. The existence and the stability of the optimization system are demonstrated. The nonlinear optimization problem is approximated by a fully discrete scheme, whose convergence is established under a novel result verified in this study that the $H^1$-norm of the solution to the discrete forward system is uniformly bounded. The iterative thresholding algorithm is proposed to solve the discrete minimization, and several numerical experiments are presented to show the efficiency and the accuracy of the algorithm.Comment: 17 pages, 2 figures, 2 table

Medicinal Plants in the Northwestern China and Their Medicinal Uses

The Northwestern China is a typical arid and semi-arid region of inner Asia, where some important medicinal species such as Angelica sinensis, Radix astragali, Radix codonopsis, Radix et rhizoma rhei, Radix glycyrrhizae, Lycium barbarum L are found and grew in the mountains areas, or desert areas. Among them, A. sinensis, R. astragali and R. glycyrrhizae are frequently used in traditional Chinese medicines and herbal prescriptions, thus encouraged many researchers to investigate and develop them. Our purpose is to provide a review of recent advances about three typical medicinal plants of A. sinensis, Astragalus membranaceus and R. glycyrrhizae in Northwestern China, mainly referring to botanical identity, chemical constituents, pharmacological studies, application in formulation, safety and cultivation practices. That will provide some valuable information for the further study and development of medicinal plants in Northwestern China

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Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/88118/1/24749_ftp.pd

Biofunctional chitosan–biopolymer composites for biomedical applications

In light of escalating biomedical demands across diverse diseases, there arises a pressing need for the development of sophisticated biocompatible materials exhibiting augmented biological functionality. Chitosan, a cationic polyelectrolyte copolymer of natural origin, distinguishes itself through its extraordinary biological properties, positioning it as a promising starting material to develop versatile biomedical materials. Tremendous attention has been directed towards the creation of high-performance biocomposites, achieved through the strategic manipulation of chitosan’s structure or its derivative, along with the amalgamation of other biopolymers. This comprehensive review intricately explores recent advancements in chitosan-based biofunctional materials, delving into formulations involving various biopolymers including polysaccharides and proteins. It places specific emphasis on the progress in chitosan chemistry and materials development, encompassing particles, hydrogels, aerogels, membranes, films, and sponges. Also, this review critically evaluates the development and functional properties of biofunctional chitosan–biopolymer composite materials, spotlighting interactions, both dynamic covalent and noncovalent, and their pivotal roles in materials formation. These interactions may either be inherent or realized through chemical modification such as “Click” chemistry, polymer grafts, mussel-inspired chemistry, and selective oxidation. Furthermore, the text illustrates the current and potential biomedical applications of these biofunctional composite materials, spanning from wound dressing to tissue engineering (skin, bone, cartilage, and nerve), the controlled release and targeted delivery of drugs/bioactive compounds, biosensing, and 3D printing. Additionally, it addresses critical challenges within the field, posits potential solutions, and provides a forward-looking perspective on the future directions of functional biomaterials and design strategies

Insights into the hierarchical structure and digestion rate of alkali-modulated starches with different amylose contents

Combined analytical techniques were used to explore the effects of alkali treatment on the multi-scale structure and digestion behavior of starches with different amylose/amylopectin ratios. Alkali treatment disrupted the amorphous matrix, and partial lamellae and crystallites, which weakened starch molecular packing and eventually enhanced the susceptibility of starch to alkali. Stronger alkali treatment (0.5% w/w) made this effect more prominent and even transformed the dual-phase digestion of starch into a triple-phase pattern. Compared with high-amylose starch, regular maize starch, which possesses some unique structure characteristics typically as pores and crystallite weak points, showed evident changes of hierarchical structure and in digestion rate. Thus, alkali treatment has been demonstrated as a simple method to modulate starch hierarchical structure and thus to realize the rational development of starch-based food products with desired digestibility