A circle graph is the intersection graph of a family of chords on a circle. There is no known characterization of circle graphs by forbidden induced subgraphs that do not involve the notions of local equivalence or pivoting operations. We characterize circle graphs by a list of minimal forbidden induced subgraphs when the graph belongs to one of the following classes: linear domino graphs, P4-t...

In this note, we prove that all 2× 2 monotone grid classes are finitely based, i.e., defined by a finite collection of minimal forbidden permutations. This follows from a slightly more general result about certain 2× 2 having two monotone cells in the same row.

Few investigations have focused on the potential uses of artisanal gold (Au) mine tailings, despite fact that mining activity contributes to environmental issues such as greenhouse gas. Mineralogical characterizations tailings in Miyove (Baradega and Masogwe) Rwanda were investigated for utilization a source valuable gold, using centrifugal separation technique. Results X-ray diffraction analys...

The Alto Quixaba pegmatite, Seridó region, northeastern Brazil, is a 60 degrees/80 degrees SW-trending subvertical dike discordantly intruded into biotite schists of the Upper Neoproterozoic Seridó Formation. It has three distinct mineralogical and textural zones, besides a replacement body that cuts the pegmatite at its central portion and in which occur, among other gem minerals, colored elba...

The purpose of this paper was to evaluate the possible use of three types of pharmaceutical grades of phyllosilicates as pharmaceutical excipients. Seven samples (two smectites, three palygorskites, and two sepiolites) were studied. A complete mineralogical and chemical characterization of each material was made and powder texture was established by image analysis of scanning electron micrograp...

[1] Mineralogical composition and pore fluid pressure are the crucial controls for mechanical stability of watersaturated sediments. Their in situ measurements were undertaken in earthquake-triggered slope deposits in Lake Lucerne (Switzerland) in addition to geophysical characterization and laboratory index properties, shear and consolidation experiments on core. Two lithological units were id...

The focus of the article is on characterization low-grade Chilisai phosphorites through a comprehensive analysis their physicochemical properties. structure this deposit was studied using modern instrumental methods, including chemical and energy-dispersive analysis, IR-Fourier spectroscopy, X-ray diffraction mineralogical analysis. According to results material composition nodular determined, ...

Let k be a natural number. We introduce k-threshold graphs. We show that there exists anO(n) algorithm for the recognition of k-threshold graphs for each natural number k. k-Threshold graphs are characterized by a finite collection of forbidden induced subgraphs. For the case k = 2 we characterize the partitioned 2threshold graphs by forbidden induced subgraphs. We introduce restricted, and spe...

Additive manufacturing (AM) has the potential to create geometrically complex parts that require a high degree of customization, using less material and producing less waste. Recent studies have shown that AM can be an economically viable option for use by the industry, yet there are some inherent challenges associated with AM for wider acceptance. The lack of standards in AM impedes its use fo...

We introduce a new hereditary class of graphs, the dominant-matching graphs, and we characterize it in terms of forbidden induced subgraphs.