Bioinspired Nanocomposites: Ordered 2D Materials Within a 3D Lattice

Composites, materials composed of two or more materials—metallic, organic, or inorganic—usually exhibit the combined physical properties of their component materials. The result is a material that is superior to conventional monolithic materials. Advanced composites are used in a variety of industrial applications and therefore attract much scientific interest. Here the formation of novel carbon‐based nanocomposites is described via incorporation of graphene oxide (GO) into the crystal lattice of single crystals of calcite. Incorporation of a 2D organic material into single‐crystal lattices has never before been reported. To characterize the resulting nanocomposites, high‐resolution synchrotron powder X‐ray diffraction, electron microscopy, transmission electron microscopy, fluorescence microscopy and nanoindentation tests are employed. A detailed analysis reveals a layered distribution of GO sheets incorporated within the calcite host. Moreover, the optical and mechanical properties of the calcite host are altered when a carbon‐based nanomaterial is introduced into its lattice. Compared to pure calcite, the composite GO/calcite crystals exhibits lower elastic modulus and higher hardness. The results of this study show that the incorporation of a 2D material within a 3D crystal lattice is not only feasible but also can lead to the formation of hybrid crystals exhibiting new properties.     

Activity of carbon-fiber-supported Fe–Co catalysts in the CO<Subscript>2</Subscript> methanation reaction

The catalytic activity of Fe–Co catalysts applied on carbon fibers of various morphologies was studied in the CO₂ methanation reaction The catalysts produced by applying the active mass on the cleaned oxygenated or cleaned reduced carbon fibers exhibited a lower activity. It was demonstrated by the SEM method that an increase of the amount of oxygen-containing functional groups on the carrier surface has a negative influence on the catalytic activity of the samples in the methanation reaction and hinders the processes of metal nitrates adjoining the carrier surface and the reduction of the active mass during the synthesis of catalysts. The sample Fe: Co = 86: 14 applied on the non-modified cleaned carbon fibers (T ₆₅ = 390°C, with \({S_{C{H_4}}}\)) showed the greatest activity in the CO₂ methanation reaction.     

Oxidation of nitride layers formed on Ti-6Al-4V alloys by gas nitriding

Ti-6Al-4V alloys were nitrided through gas nitriding at 950 °C for 3 h in deoxygenated, atmospheric nitrogen gas. During nitriding, nitrogen reacted and diffused into the alloys to form Ti₂N and a meager amount of TiN in a Ti-N compound layer with a thickness of 20 μm to 25 μm. An α-Ti(N) diffusion layer with a thickness of 40 μm to 80 μm formed below this layer. A small amount of Al was dissolved at the top of the Ti-N compound layer because of the strong interaction of nitrogen with Ti and Al. Nitriding resulted in the dissolution of interstitial nitrogen and the formation of nitrides. Oxidation of the nitrided Ti-6Al-4V alloys initially resulted in the formation of a Ti-N-O layer, which later oxidized to TiO₂. Above 800 °C, the nitrided alloys oxidized rapidly, accompanied by microcracking of the TiO₂ surface layer.     

Age and Chronodisruption in Mouse Heart: Effect of the NLRP3 Inflammasome and Melatonin Therapy

Age and age-dependent inflammation are two main risk factors for cardiovascular diseases. Aging can also affect clock gene-related impairments such as chronodisruption and has been linked to a decline in melatonin synthesis and aggravation of the NF-κB/NLRP3 innate immune response known as inflammaging. The molecular drivers of these mechanisms remain unknown. This study investigated the impact of aging and NLRP3 expression on the cardiac circadian system, and the actions of melatonin as a potential therapy to restore daily rhythms by mitigating inflammaging. We analyzed the circadian expression and rhythmicity of clock genes in heart tissue of wild-type and NLRP3-knockout mice at 3, 12, and 24 months of age, with and without melatonin treatment. Our results support that aging, NLRP3 inflammasome, and melatonin affected the cardiac clock genes expression, except for Rev-erbα, which was not influenced by genotype. Aging caused small phase changes in Clock, loss of rhythmicity in Per2 and Rorα, and mesor dampening of Clock, Bmal1, and Per2. NLRP3 inflammasome influenced the acrophase of Clock, Per2, and Rorα. Melatonin restored the acrophase and the rhythm of clock genes affected by age or NLRP3 activation. The administration of melatonin re-established murine cardiac homeostasis by reversing age-associated chronodisruption. Altogether, these results highlight new findings about the effects aging and NLRP3 inflammasome have on clock genes in cardiac tissue, pointing to continuous melatonin as a promising therapy to placate inflammaging and restore circadian rhythm in heart muscle. Additionally, light microscopy analysis showed age-related morphological impairments in cardiomyocytes, which were less severe in mice lacking NLRP3. Melatonin supplementation preserved the structure of cardiac muscle fibers in all experimental groups.     

Role of amphiphilic organic additives in design of silica materials with ordered mesoporous structure

Journal of Porous Materials - Templated sol–gel synthesis of silica materials with hexagonally ordered mesoporous structure was realized in the presence of amphiphilic organic compounds (azo...     

Proton Conductive Membranes from Covalently Cross-Linked Poly(Acrylate)/Silica Interpenetrating Networks

The preparation of hybrid proton conductive membranes that comprise of covalently linked interpenetrating polymer and inorganic networks is reported. The hybrid membranes are synthesized via simultaneous photo-initiated polymerization and sol–gel processing. The simultaneous processing permeates fabrication of the membranes that comprises covalently cross-linked polymeric and inorganic networks. The membranes are characterized by attenuated total reflectance-Fourier transform infrared spectroscopy, scaning electron microsopy, thermogravimetric analysis, differential scanning calorimetry, in order to confirm their chemical composition, structure, and morphology. An addition of 3-methacryloxypropyl trimethoxysilane into the sol–gel composition allows the formation of covalent linkages between polymeric and inorganic networks, which facilitates a uniform distribution of the molecular components across the fabricated membranes. The incorporation of the silica network leads to an increase in water retention and proton conductivity of hybrid membranes as compared to their purely polymeric analogues.     

Diagnostic Neuro-Fuzzy System and Its Learning in Medical Data Mining Tasks in Conditions of Uncertainty about Numbers of Attributes and Diagnoses

Architecture and learning method for evolving diagnostic neuro-fuzzy-system for Medical Data Mining tasks in situation of uncertainty about quantities of attributes and diagnoses are proposed. Diagnostic neuro-fuzzy-system was approbated on data set, which present erosive ulcerous disease of the gastrointestinal tract and shown high quality of classification in condition of different quantity of input and output data.     

Link prediction of scientific collaboration networks based on information retrieval

Link prediction plays an important role in scientific collaboration networks, and can favourably affect the organization of international scientific projects. In this paper, a meta-path computed prediction (MPCP) algorithm for link prediction among scientists and publications is presented. The MPCP algorithm is based on a heterogeneous information network model composed of authors and keywords in articles retrieved from the Web of Science database. Two kinds of meta-paths are defined: Author to Author to Author (A-A-A) and Author to Direction to Author (A-D-A). By calculating A-A-A and A-D-A using the heterogeneous information network model, the predictive strength of the links can be computed. The overlap of the meta-paths is also taken into account. By restoring links and calculating the number of restored links with different standard values, similar results are achieved for (quantum communication and link prediction). The number of restored links decreases as a special threshold value increases. The experimental studies show that, for any threshold value up to 1, at least 50% of links are restored. The results presented in this paper verify that the algorithm is a feasible means of predicting collaboration among scientists.