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Abstract Fiber‐reinforced hydrogel composites are widely employed in many engineering applications, such as drug release, and flexible electronics, with more flexible mechanical properties than pure hydrogel materials. Comparing to the hydrogel strengthened by continuous fiber, the meta‐fiber reinforced hydrogel provides stronger individualized design ability of deformation patterns and tunable stiffness, especially for the elaborate applications in joint, cartilage, and organ. In this paper, a novel structure design strategy based on deep learning algorithm is proposed for hydrogel reinforced by meta‐fiber to achieve targeted mechanical properties, such as stress and displacement fields. A solid mechanic model for meta‐fiber reinforced hydrogel is first developed to construct the dataset of fiber distribution and the corresponding mechanical properties of the composite. Generative adversarial network (GAN) is then trained to characterize the relationship between stress or displacement field, and meta‐fiber distribution. The well‐trained GAN is implemented to design meta‐fiber reinforced hydrogel composite structure under specific operation conditions. The results show that the deep learning method may efficiently predict the structure of the hydrogel composite with satisfied confidence, and has great potential for applications in drug delivery and flexible electronics.

Photothermal therapy is a treatment method which used a material with a high conversion efficiency of field or biological synthetic material, using target recognition technology gathered near the cancer tissues after injected into human bodies, with near-infrared convert light energy into heat energy to kill cancer. Here reported the biocompatible use of gold nanorods(GRNs) as probes for cancer targeting in vitro. More specifically, this paper demonstrated a progressive synthesis approach in fabricating water-dispersible gold nanorods. These nanorods were prepared by replacing cetyltrimethylammonium bromide with a mixture of 15-polypeptide(15P) molecules, such that a variety of cell viability assays did not reveal any signals of toxicity in the treated cells. The samples size was estimated to be 70-80 nm; Dynamic light scattering reveals that the cores of the gold nanorods are protected from the outside environment by the 15-polypeptide. Photothermal treatment indicated that 15P-GNRs can stain tumor growth and devoted the pivotal steps in promoting of the use of ternary GNRs as a tumor targeting, more importantly, these results suggest that 15P-GNRs can serve as biocompatible synthetic material and multimodal platform for various bio-applications and the micelle-encapsulated nanoparticles formulation was able to target the tumor site directly. On the other hand, Photothermal therapy has great effect in killing cancer cell with near-infrared.

C. testosteroni is a research topic that can degrade steroid hormones into water and carbon dioxide through a series of enzymes in the body. Short-chain dehydrogenase (SDR) are a class of NAD (P) H-dependent oxidoreductases in C. testosteroni. Its main function is catalyzing the redox of the hydroxyl/ketone group of the hormone. In this paper, a SDR gene(SDRx) is cloned from C. testosteroni ATCC11996 and expressed. The polyclonal antibody was prepared and the SDRx gene knocked out by homologous recombination. Wild type and mutant C. testosteroni induced by testosterone, estradiol, estrone and estriol. The growth curves of the bacteria were measured by spectrophotometer. ELISA established the expression of SDRx protein, and high-performance liquid chromatography(HPLC) detected the contents of various hormones. The results show that the growth of wild type was faster than mutant type induced by testosterone. The concentration of SDRx is 0.318 mg/ml under testosterone induction. It has a great change in steroid hormones residue in culture medium measured by HPLC: Testosterone residue in the mutant type group was 42.4 % more than the wild type in culture medium. The same thing happens with induced by estrone. In summary, this SDRx gene involved in the degradation of testosterone and estradiol, and effects the growth of C. testosteroni.

Photothermal therapy has great significant as a new technology for cancer treatment without side effects. Especially with near-infrared laser as the driving force, which has shown a promising prospect in cancer treatment. However, its application is based on the development of near-infrared laser response of photothermal conversion nanomaterials. Nanogold materials have been studied for a long time as light sensitive materials. The main reason is the surface of the plasmon resonance effect can be adjusted by surface, size and structure, which could make them have excellent performance while absorbing the specific optical wavelength and completing energy convertion. We used the biocompatible gold nano-rods (GNRs) as probes for cancer targeting in order to introduce a progressive synthesis approach in fabricating water-dispersible gold nanorods. These nanorods were prepared by replacing cetyltrimethylammonium bromide with a mixture of 15-polypeptide(15P) molecules. The nano size was estimated about 70 - 80 nm by electron microscope. The result of dynamic light scattering showed that the cores of the gold nanorods were protected from the outside environment by the 15-polypeptide. Photothermal treatment indicated that 15P-GNRs could stain tumor growth and devote the pivotal steps in promoting cancer cell death with near-infrared laser irradiation. More importantly, these results proved that 15P-GNRs has good bio-compatiblility and can be considered as photothermal conversion material for targeting the ovarian tumor. [ABSTRACT FROM AUTHOR]

Conductive atomic force indentation (CAFI) was proposed to study the self-repair behaviour of the neuronal cell membrane here. CAFI was used to detect the changes of membrane potentials by performing the mechanical indentation on neurons with a conductive atomic force microscope. In the experiment, a special insulation treatment was made on the conductive probe, which turned out to be a conductive nanoelectrode, to implement the CAFI function. The mechanical properties of the neuronal cell membrane surface were tested and the membrane potential changes of neurons cultured in vitro were detected. The self-repair behaviour of the neuronal cell membrane after being punctured was investigated. The experiment results show that CAFI provides a new way for the study of self-repair behaviours of neuronal cell membranes and mechanical and electrical properties of living cells. [ABSTRACT FROM AUTHOR]

By simply running the reactions under air and solvent-free conditions using catalytic amounts of manganese dioxide, a practical and efficient N-alkylation method for a variety of sulfonamides and amines using alcohols as green alkylating reagents was developed. [ABSTRACT FROM AUTHOR]

The thermo dynamically unfavorable anaerobic dehydrogenative alcohol activation to aldehydes and hydridometal species is found to be the bottleneck in metal-catalyzed N-alkylations due to a general and unnoticed catalyst deactivation by amines/ amides. Thus, different from the anaerobic dehydrogenation process in borrowing hydrogen or hydrogen autotransfer reactions that require noble metal complexes or addition of capricious ligands for catalyst activation, the water-producing, exothermic, metal-catalyzed aerobic alcohol oxidation is thermodynamically more favorable and the most effective and advantageous aldehyde generation protocol. This leads to a general and advantageous air-promoted metal-catalyzed aerobic N-alkylation methodology that effectively uses many simpler, less expensive, more available, and ligand-free metal, catalysts that were inactive under typical anaerobic borrowing hydrogen conditions, avoiding the use of preformed metal complexes and activating ligands and the exclusive requirement of inert atmosphere protection. This aerobic method is quite general in substrate scope and tolerates various amides, amines, and alcohols, revealing its potentially broad utilities and interests in academy and industry- In contrast to the commonly accepted borrowing hydrogen mechanism, based on a thorough mechanistic study and supported by the related literature background, a new mechanism analogous to the relay race game that has never been proposed in metal-catalyzed N-alkylation reactions is presented. [ABSTRACT FROM AUTHOR]

Microwave irradiation was found to promote tetrabutylammonium fluoride catalyzed nucleophilic aromatic substitution of aryl fluorides and arylthiotrimethylsilanes, affording high yields of unsymmetrical diaryl thioethers efficiently under mild, transitionmetal-and base-free conditions. Microwave showed unusual improvement on the reaction in not only the conditions and reaction rate, but also in selectivity and substrate scope. [ABSTRACT FROM AUTHOR]