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821.
822.
Glucose biofuel cells (GBFCs) are highly promising power sources for implantable biomedical and consumer electronics because they provide a high energy density and safety. However, it remains a great challenge to combine their high power density with reliable long‐term stability. In this study, a novel GBFC design based on the enzyme biocatalysts glucose dehydrogenase, diaphorase, and bilirubin oxidase immobilized in rolled‐up titanium nanomembranes is reported. The setup delivers a maximum areal power density of ≈3.7 mW cm?2 and a stable power output of ≈0.8 mW cm?2. The power discharges over 452 h, which is considerably longer than reported previously. These results demonstrate that the GBFC design is in principle a feasible and effective approach to solve the long‐term discharge challenge for implantable biomedical device applications.  相似文献   
823.
824.
The main goal of vital pulp therapy (VPT) is to preserve the vitality of the pulp tissue, even when it is exposed due to bacterial invasion, iatrogenic mechanical preparation, or trauma. The type of new dentin formed as a result of VPT can differ in its cellular origin, its microstructure, and its barrier function. It is generally agreed that the new dentin produced by odontoblasts (reactionary dentin) has a tubular structure, while the dentin produced by pulp cells (reparative dentin) does not or has less. Thus, even VPT aims to maintain the vitality of the pulp. It does not regenerate the dentin pulp complex integrity. Therefore, many studies have sought to identify new therapeutic strategies to successfully regenerate the dentin pulp complex. Among them is a Wnt protein-based strategy based on the fact that Wnt proteins seem to be powerful stem cell factors that allow control of the self-renewal and proliferation of multiple adult stem cell populations, suitable for homeostasis maintenance, tissue healing, and regeneration promotion. Thus, this review outlines the different agents targeting the Wnt signaling that could be applied in a tooth environment, and could be a potential therapy for dentin pulp complex and bone regeneration.  相似文献   
825.
This paper is intended as one of a series on processes of decoration of pottery, and is a discussion of modeled treatment, where and how it is successful decoratively and from the point of view of practicality. The process of modeling with coils in low relief is given in detail. Vigorous pattern is used if the glazes are to be matt because of the thicker nature of the glaze which will obliterate subtlety in the modeling. Delicate pattern is used under thinner and more fluid glazes. Formulas are given for one series of vivid colors of a matt glaze and for a treatment of transparent, rather neutral glazes, on a clay red-orange in color.  相似文献   
826.
A 3D printing approach to design and produce cellular scaffolds with a precise tunable pore architecture, in terms of size, fraction, and interconnectivity is reported. Different metallic inks are formulated by mixing hydrogel with Ti–6Al–4V atomized powders of various sizes. After 3D printing by direct-ink writing (DIW) followed by debinding and sintering, the fraction and size of macropores ( D > 100 μm , designed by computer-aided design (CAD)) and micropores ( D < 10 μm , remaining after sintering), the roughness and the microstructure are determined by high-resolution X-ray tomography and electron microscopy, and correlated to the initial powder size. It is shown that playing with initial powder size allows designing different pore architectures, from interconnected micropores to fully dense filaments. These phenomena are combined with a multi-inks DIW approach to fabricate architectured structures with graded microporosity. This new route is promising for the production of functional materials, such as biomedical scaffolds or implants, with tunable osseointegration, stiffness, and strength. The micropores could also be loaded with active molecules and positioned according to release needs.  相似文献   
827.
828.
Alcohol dehydrogenases (ADH) are important tools for generating chiral α-hydroxyketones. Previously, only the ADH of Thauera aromatica was known to convert cyclic α-diketones with appropriate preference. Here, we extend the spectrum of suitable enzymes by three alcohol dehydrogenases from Citrifermentans bemidjiense (CibADH), Deferrisoma camini (DecADH), and Thauera phenylacetica (ThpADH). Of these, DecADH is characterized by very high thermostability; CibADH and ThpADH convert α-halogenated cyclohexanones with increased activity. Otherwise, however, the substrate spectrum of all four ADHs is highly conserved. Structural considerations led to the conclusion that conversion of diketones requires not only the expansion of the active site into a large binding pocket, but also the circumferential modification of almost all amino acid residues that form the first shell of the binding pocket. The constellation appears to be overall highly specific for the relative positioning of the carbonyl functions and the size of the C-ring.  相似文献   
829.
830.
Thieno[2,3-d][1,2,3]thiadiazole-6-carboxylates 3 belong to a new group of plant protecting agents as highly potent inducers of systemic acquired resistance (SAR). In order to obtain an enhanced basis set for structure activity relationship studies several modifications of the heteroaromatic core were performed by introduction of various substituents. One approach utilizing metallation techniques led to several 5-substituted derivatives 4a – h of the title compound. Using the chloro-compound 5 obtained via this route the ability to undergo nucleophilic substitution reactions was investigated, representing a complementary strategy towards derivatives 6a – c .  相似文献   
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