Cobalt-catalyzed tunable carbon microstructures from halogenated SiC preceramic precursors

Carbide-derived carbons (CDCs) with highly graphitized domains, linear, oval-shaped, and barrel-like structures have been prepared from a silicon carbide preceramic precursor containing catalytic amounts of cobalt. The chlorination temperature as well as the amount of catalysts will determine the specific surface area, pore size, and morphology of the obtained carbons. At low chlorination temperature, an amorphous network with significant amount of double or single oxygenated bonds was obtained. At 700 and 800°C both linear graphitic domains and barrel-like carbon dominate the microstructure with an increased presence of microporosity. There barrel-like structures provided increased specific capacitance, although the high anisotropy of the structure compromises the energy density of the device. At 900°C, despite the disappearance of this cropped surface, the hierarchical pore distribution and low O content also induce an increase of the specific capacitance of the CDC samples regardless of their high percentage of micropores.     

On the use of double-skinned membranes to prevent chemical interaction between membranes and catalysts

This communication summarizes the use of double-skinned membranes for hydrogen separation in presence of TiO₂ based catalyst (PtReCe/TiO₂). The use of this type of membrane avoids the direct contact between catalyst particles and surface of the Pd-based hydrogen selective layer due to the presence of a mesoporous YSZ/γ-Al₂O₃ layer. The PdAg layer is protected by the mesoporous layer from direct contact with catalyst particles, avoiding erosion and possible chemical interactions. In comparison with a conventional PdAg membrane, the hydrogen flux of DS-membrane was observed not to be compromised during test carried out at 400 °C.     

A comparative assessment of thin-film photovoltaic production processes using the ELECTRE III method

The use of renewable energy sources for the production of electric power brings huge benefits both in terms of environmental protection as well as savings in non-renewable resources. Photovoltaic stands out from other renewable energy sources for its simplicity and the modularity of its energy conversion system. To date, the most highly developed technology for the construction of solar cells is one based on mono and polycrystalline silicon. An alternative production line is currently under development to produce, thin-film modules. There are currently a variety of processes and materials available to make thin-film cells but their relative costs and performance differ. Therefore, it would be useful to make a comparative evaluation of the different processes using a multiple criteria method.     

A 6 × 6 Cells Interconnection-Oriented Programmable Chip for CNN

The implementation of a versatile VLSI chip certainly represents an important step to improve the research on Cellular Neural Networks. In this paper a VLSI realization of the multi-chip oriented, the 6 × 6 Digitally Programmable Cellular Neural Network (6 × 6 DPCNN) chip, will be presented. This chip covers most of the available one-neighbourhood templates for image processing applications. Moreover, it can be easily interconnected to others to carry out very large CNN arrays. The designs and some measured results of a single chip and a multi-chip board (the 720 DPCNN System) will be shown.     

Compressive evaluation of mansory bricks produced with industrial byproduct aggregates

This study evaluates the effect upon the compressive strength of ceramic masonry bricks when industrial byproducts known as soot are added. The research includes an analysis of the granulometric properties of the constituent components, performed manually with ASTM C136-01 screens to determine particle size using apertures sized from large to small; an analysis by XRD of the mineralogical phases present; a compressive strength analysis performed using standard compression testing machinery; and a water absorption measurement calculated according to Colombian Technical Standard: 4017:2015—Methods for the Sampling and Testing of Masonry Elements and other Clay Products. Five trials were performed using different mixtures of clay and soot, at substitution rates of 20%, 30%, 40%, 50%, and 60%. These mixtures were prepared under identical conditions in order to ensure validity of the resulting comparisons. The results showed that bricks with 20%, 30%, 40%, and 50% added soot demonstrated superior structural strength compared to conventional units. Bricks incorporating 60% soot, however, were found to have lower strength and high porosity.     

Hydrogen production from methanol by oxidative steam reforming carried out in a membrane reactor

The aim of this work is to study from an experimental point of view the oxidative steam reforming of methanol by investigating the behaviour of a dense Pd/Ag membrane reactor (MR) in terms of methanol conversion as well as hydrogen production. The main parameters considered are the operating temperature and the O₂/CH₃OH feed ratio. This is a pioneer work in the application of MR to this kind of reaction, whose goal should be to produce a CO-free hydrogen stream suitable for hydrogen fuel cell applications. The experimental results show that the MR gives methanol conversions higher than traditional reactors (TRs) at each temperature investigated, confirming the good potential of the membrane reactor device for this interesting reaction system.     

Convergence for a family of discrete advection–reaction operators

We define a family of discrete Advection–reaction operators, denoted by $A_{a\lambda }$, which associate to a given scalar sequence $s=\left\{s_n\right\}$ the sequence given by $A_{a\lambda }\left(s\right)\equiv \left\{b_n\right\}$, where $b_n=a_{n?2}{s}_{n?1}+{\lambda }_n{s}_n$ for $n=1,2,\dots$. For $A_{a\lambda }$ we explicitly find their iterates and study their convergence properties. Finally, we show the relationship between the family of discrete operators with the continuous one dimensional advection–reaction equation.     

Identification of differentially expressed proteins in papillary thyroid carcinomas with V600E mutation of BRAF

BRAF, a serine/threonine kinase of the RAF family, is a downstream transducer of the RAS-regulated MAPK pathway. V600E mutation of BRAF protein is the most common genetic alteration occurring in papillary thyroid carcinomas and is prognostic of poor clinicopathological outcomes. Protein expression in the subclass of PTC bearing the BRAF(V600E) mutation was investigated by using 2-DE and MS/MS techniques and compared to that of matched normal thyroid tissues from seven patients. 2-D gel image analysis revealed that the expression of eight polypeptide spots, corresponding to five proteins, were significantly underexpressed in PTC bearing BRAF(V600E) mutation whereas 25 polypeptides, representing 19 distinct proteins, were significantly upregulated in tumour tissue, as compared to normal thyroid. Among the differentially expressed polypeptides, mitochondrial proteins, ROS-scavenger enzymes, apoptosis-related proteins as well as proteins involved in tumour cell proliferation were identified. Although dissimilarities between the present results and those previously reported can be ascribed to the use of different 2-DE techniques, the possibility that BRAF(V600E) mutation is responsible for changes in protein expression distinct from those induced by other oncogenes cannot be ruled out.     

Molecular Profiling and Novel Therapeutic Strategies for Mucosal Melanoma: A Comprehensive Review

Mucosal melanoma is a rare and aggressive subtype of melanoma. Unlike its cutaneous counterpart, mucosal melanoma has only gained limited benefit from novel treatment approaches due to the lack of actionable driver mutations and poor response to immunotherapy. Over the last years, whole-genome and exome sequencing techniques have led to increased knowledge on the molecular landscape of mucosal melanoma. Molecular studies have underlined noteworthy findings with potential therapeutic implications, including the presence of KIT mutations, which are potential targets of tyrosine kinase inhibitors currently in use in the clinic (imatinib), but also SF3B1 mutation, CDK4 amplifications, and CDKN2A gene deletions, which are presently under investigation in clinical trials. Recent results from a pooled analysis of patients with mucosal melanoma treated with immunotherapy have suggested that the combination of immune checkpoint inhibitors might improve survival outcomes in this subset of patients, as compared with single-agent immunotherapy. However, these results are not confirmed across different studies, and combo-immunotherapy correlates with a higher rate of adverse events. In this review, we describe the clinical, biological, and genetic features of mucosal melanoma. We also provide an update on the results of approved systemic treatment in this setting and overview the therapeutic strategies currently under investigation in clinical trials.