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The Regional Natural Park of the Monts d'Ardèche, located in south-eastern France, became the Monts d’Ardèche UNESCO Global Geopark in September 2014. This territory possesses significant volcanic features dating from the Miocene to the late Pleistocene. The UNESCO Global Geopark label helped to formalize a long-standing partnership with the University of Clermont Auvergne which includes support for scientific research, establishing conservation and protection priorities, establishing geosites for the public and involvement of local people and communities in geotouristic initiatives. Here we focus on some peculiar geosites that allow us to question magmatic processes, eruptive dynamics, morphological evolution of landscapes, the chronology of eruptions, relationships between humans and volcanoes during the Pleistocene, and highlight the delicate alliance between economic pressures, heritage conservation, and scientific tourism.

Automorphisms and endomorphisms are actively used in various theoretical studies. In particular, the theoretical interest in the study of automorphisms is due to the possibility of representing elements of a group by automorphisms of a certain algebraic system. For example, in 1946, G. Birkhoff showed that each group is the group of all automorphisms of a certain algebra. In 1958, D. Groot published a work in which it was established that every group is a group of all automorphisms of a certain ring. It was established by M. M. Glukhov and G. V. Timofeenko: every finite group is isomorphic to the automorphism group of a suitable finitely defined quasigroup. In this paper, we study endomorphisms of certain finite groupoids with a generating set of $k$ elements and order $k + k^2$, which are not quasigroups and semigroups for $k>1$. A description is given of all endomorphisms of these groupoids as mappings of the support, and some structural properties of the monoid of all endomorphisms are established. It was previously established that every finite group embeds isomorphically into the group of all automorphisms of a certain suitable groupoid of order $ k + k^2$ and a generating set of $k$ elements. It is shown that for any finite monoid $G$ and any positive integer $k\geq|G|$ there will be a groupoid $S$ with a generating set of $k$ elements and order $k+k^2$ such that $G$ is isomorphic to some submonoid of the monoid of all endomorphisms of the groupoid $S$.

Abstract The viscosity of volcanic melts is a dominant factor in controlling the fluid dynamics of magmas and thereby eruption style. It can vary by several orders of magnitude, depending on temperature, chemical composition, and water content. The experimentally accessible temperature range is restricted by melt crystallization and gas exsolution. Therefore, modeling viscosity as a function of temperature and water content is central to physical volcanology. We present a model that describes these dependencies by combining a physically motivated equation for temperature dependence of viscosity and a glass transition temperature (Tg) model for the effects of water. The equation uses the viscosity at infinite temperature η∞, Tg, and the steepness factor m as fitting parameters. We investigate the effect of leaving η∞ free as a parameter and fixing its value, by fitting anhydrous viscosity data of 45 volcanic melts using the temperature dependent model. Both approaches describe experimental data well. Using a constant η∞ therefore provides a viable route for extrapolating viscosity from data restricted to small temperature intervals. Our model describes hydrous data over a wide compositional range of terrestrial magmas (26 data sets) with comparable or better quality than literature fits. With η∞ constrained, we finally apply our model to viscosities derived by differential scanning calorimetry and find—by comparing to viscometry based data and models—that this approach can be used to reliably describe the dependence of viscosity on temperature and water content. This introduces important implications for modeling the effects of nanostructure formation on viscosity.

The purpose of our study was to evaluate Magmas as a potential target in prostate cancer. In addition, we evaluated our synthetic Magmas inhibitor (BT#9) effects on prostate cancer and examined the molecular mechanism of BT#9. A cell viability assay showed that treatment with BT#9 caused a significant decrease in the viability of DU145 and PC3 prostate cancer cells with little effect on the viability of WPMY-1 normal prostate cells. Western blot proved that BT#9 downregulated the Magmas protein and caspase-3 activation. Flow cytometry studies demonstrated increased apoptosis and disturbed mitochondrial membrane potential. However, the main mode of cell death was caspase-independent necrosis, which was correlated with the accumulation of mitochondrial and intra-cellular Reactive Oxygen Species (ROS). Taken together, our data suggest Magmas is a potential molecular target for the treatment of prostate cancer and that Magmas inhibition results in ROS-dependent and caspase-independent necrotic cell death.

Prior research has shown how incorporating group theory into upper secondary school or undergraduate mathematics education may positively impact learners’ conceptual understanding of mathematics in general and algebraic concepts in particular. Despite a recently increasing number of empirical research into student learning of introductory group theory, the development of a concept inventory that allows for the valid assessment of a respective conceptual understanding constitutes a desideratum to date. In this article, we contribute to closing this gap: We present the development and evaluation of the Concept Inventory of Introductory Group Theory—the CI2GT. Its development is based on a modern mathematics education research perspective regarding students‘ conceptual mathematics understanding. For the evaluation of the CI2GT, we follow a contemporary conception of validity: We report on results from two consecutive studies to empirically justify that our concept inventory allows for a valid test score interpretation. On the one hand, we present N=9 experts‘ opinions on various aspects of our concept inventory. On the other hand, we administered the CI2GT to N=143 pre-service primary school teachers as a post-test after a two weeks course into introductory group theory. The data allow for a psychometric characterization of the instrument, both from classical and probabilistic test theory perspectives. It is shown that the CI2GT has good to excellent psychometric properties, and the data show a good fit to the Rasch model. This establishes a valuable new concept inventory for assessing students’ conceptual understanding of introductory group theory and, thus, may serve as a fruitful starting point for future research into student learning of abstract algebra.

In this paper, we present a novel concept for an abstract algebra course at the secondary school level. Against the backdrop of findings from mathematics education research, we discuss benefits that arise from teaching abstract algebra to secondary school students. We derive suitable content items as well as educational ideas on how to implement them into mathematics classrooms. We build on frameworks from mathematics education research to design a teaching-learning sequence that enables a beneficial learning trajectory across three units—the result is a coherent teaching concept that encompasses Magmas in a hands-on way. It can be used for either extra-curricular activities or advanced courses in mathematics classes, and can be of benefit for mathematics learners.

In the paper the families of finite semi-automata and reversible finite Mealy and Moore automata over finite magmas are defined and analyzed in detail. On the base of these models it is established that the set of finite quasigroups is the most acceptable subset of the set of finite magmas at resolving model problems in Cryptography, such as design of iterated hash functions and stream ciphers. Defined families of finite semi-automata and reversible finite automata over finite $T$-quasigroups are investigated in detail. It is established that in this case models time and space complexity for simulation of the functioning during one instant of automaton time can be much lower than in general case.

The purpose of this article is to analyze the philosophy of values developed by Cornelius Castoriadis from his theory of the imaginary institution of societies. By understanding the emergence of imaginary significations, it is possible to identify their manifestations through the representations, the affects and the intentions of individuals. In this context, values correspond to a series of significations that motivate the conduct of individuals. In fact, in a specific society, individuals believe in symbols that make sense for them. The presentation of the values does not reflect a moral project, but rather a socio-political construction that must be carefully described in order to identify the alteration of values over time. The article explores the way in which Castoriadis poses the problem of the persistence of past values with the risk of depending on established norms without being able to really transform them. In this perspective, Castoriadis refers to a fundamental value which is that of autonomy capable of questioning existing imaginaries.

The purpose of this article is to analyze the philosophy of values developed by Cornelius Castoriadis from his theory of the imaginary institution of societies. By understanding the emergence of imaginary significations, it is possible to identify their manifestations through the representations, the affects and the intentions of individuals. In this context, values correspond to a series of significations that motivate the conduct of individuals. In fact, in a specific society, individuals believe in symbols that make sense for them. The presentation of the values does not reflect a moral project, but rather a socio-political construction that must be carefully described in order to identify the alteration of values over time. The article explores the way in which Castoriadis poses the problem of the persistence of past values with the risk of depending on established norms without being able to really transform them. In this perspective, Castoriadis refers to a fundamental value which is that of autonomy capable of questioning existing imaginaries.

The purpose of this article is to analyze the philosophy of values developed by Cornelius Castoriadis from his theory of the imaginary institution of societies. By understanding the emergence of imaginary significations, it is possible to identify their manifestations through the representations, the affects and the intentions of individuals. In this context, values correspond to a series of significations that motivate the conduct of individuals. In fact, in a specific society, individuals believe in symbols that make sense for them. The presentation of the values does not reflect a moral project, but rather a socio-political construction that must be carefully described in order to identify the alteration of values over time. The article explores the way in which Castoriadis poses the problem of the persistence of past values with the risk of depending on established norms without being able to really transform them. In this perspective, Castoriadis refers to a fundamental value which is that of autonomy capable of questioning existing imaginaries.

Understanding the dynamics of the magmatic evolution of the interior of the Moon requires accurate knowledge of the viscosity (η) of lunar magmas at high pressure (P) and high temperature (T) conditions. Although the viscosities of terrestrial magmas are relatively well-documented, and their relation to magma composition well-studied, the viscosities of lunar titano-silicate melts are not well-known. Here, we present an experimentally measured viscosity dataset for three end member compositions, characterized by a wide range of titanium contents, at lunar-relevant pressure-temperature range of ∼1.1–2.4 GPa and 1830–2090 K. In situ viscometry using the falling sphere technique shows that the viscosity of lunar melts varies between ∼0.13 and 0.87 Pa-s depending on temperature, pressure and composition. Viscosity decreases with increasing temperature with activation energies for viscous flow of Ea = 201 kJ/mol and Ea = 106 kJ/mol for low-titanium (Ti) and high-Ti melts, respectively. Pressure is found to mildly increase the viscosity of these intermediate polymerized melts by a factor of ∼1.5 between 1.1 and 2.4 GPa. Viscosities of low-Ti and high-Ti magmas at their respective melting temperatures are very close. However at identical P-T conditions (∼1.3 GPa, ∼1840 K) low-Ti magmas are about a factor of three more viscous than high-Ti magmas, reflecting structural effects of Si and Ti on melt viscosity. Measured viscosities differ significantly from empirical models based on measurements of the viscosity of terrestrial basalts, with largest deviations observed for the most Ti-rich and Si-poor composition. Viscosity coefficients for these primitive lunar melts are found to be lower than those of common terrestrial basalts, giving them a high mobility throughout the lunar mantle and onto the surface of the Moon despite their Fe and Ti-rich compositions.

Epithelial ovarian cancer (EOC) constitutes 90% of ovarian cancers (OC) and is the eighth most common cause of cancer-related death in women. The cancer histologically and genetically is very complex having a high degree of tumour heterogeneity. The pathogenic variability in OC causes significant impediments in effectively treating patients, resulting in a dismal prognosis. Disease progression is predominantly influenced by the peritoneal tumour microenvironment rather than properties of the tumor and is the major contributor to prognosis. Standard treatment of OC patients consists of debulking surgery, followed by chemotherapy, which in most cases end in recurrent chemoresistant disease. This review discusses the different origins of high-grade serous ovarian cancer (HGSOC), the major sub-type of EOC. Tumour heterogeneity, genetic/epigenetic changes, and cancer stem cells (CSC) in facilitating HGSOC progression and their contribution in the circumvention of therapy treatments are included. Several new treatment strategies are discussed including our preliminary proof of concept study describing the role of mitochondria-associated granulocyte macrophage colony-stimulating factor signaling protein (Magmas) in HGSOC and its unique potential role in chemotherapy-resistant disease.

The ~1.88 Ga Vaasa Batholith in western Finland is a large granitoid area (8 000 km2) with gradational contacts against the garnet- and cordierite-bearing diatexite and metatexite migmatites of the Pohjanmaa Belt. It is located in the middle part of the Fennoscandian Shield and was formed during the Svecofennian orogeny (1.9–1.8 Ga). The Batholith area consists of porphyritic and even-grained granodiorite with smaller proportions of granite and pyroxene granitoid. The various phases in the Vaasa Batholith mainly grade into each other and usually contain relicts of Ca concretions and schists, biotite and garnet, locally resembling uniform diatexites. All the phases are peraluminous in composition. The Mg# of biotite in the granodiorites and pyroxene tonalites is high (50–60), in contrast to lower values in the granite (20–35). Orthopyroxene in the tonalite has an elevated Mg# value and Al2O3 concentration. In Harker diagrams, bulk composition of the tonalites, granodiorites and granites of the Vaasa Batholith evolves along the same path, but the metatexites are beyond or cutting the path. The textural, mineralogical and chemical continuity between the granodiorites of the Vaasa Batholith and the adjacent diatexites indicate that the Vaasa Batholith represents a magma layer formed by extensive in situ melting of the crust. The diatexites are mainly from the inhomogeneous magma, although they texturally grade to the metatexites. The Vaasa Batholith and adjacent diatexites are separated from the metatexites of the Pohjanmaa Belt by ‘magma interface’ (MI). The metatexites formed in a conduction heat flow zone above the MI. The Vaasa Batholith is an exceptional type example of the voluminous and diverse granitoids in Finland.

The 1630 Ma Jaala-Iitti complex is an example of bimodal rapakivi granite magmatism in which the interaction of granite and diabase magmas have led locally to hybridization. The dyke-like complex is situated at the northwestern margin of the Wiborg rapakivi batholith in southeastern Finland, cutting both the Proterozoic Svecofennian metamorphic crust and the Wiborg batholith. The complex consists mainly of non-hybridized compositionally homogeneous granites, i.e., hornblende granite and hornblende-quartz-feldspar porphyry which represent the felsic end-member (ca. 68 wt% SiO2) of the complex. The mafic end-member (ca. 51 wt% SiO2) is present as globules of disaggregated Fe-rich tholeiitic magma forming magmatic mafic enclaves (MMEs) and composite MMEs. Commonly MMEs and large (up to 2 metres in diameter) pillow-like MMEs show magma mixing and mingling characteristics. Hybrid rocks in the complex are monzogranitic and are characterized by (a) quartz grains and quartz aggregates (partially melted xenoliths) mantled by amphibole rims (ocellar texture) with occasional augite, (b) alkali feldspar megacrysts mantled by a micrographic plagioclase-quartz intergrowth, and (c) alkali feldspar megacrysts mantled by a plagioclase shell with occasional amphibole inclusions. These textures are also found in hybrid MMEs and especially in pillow-like MMEs. Alkali feldspar and quartz megacrysts in hybrid rocks are derived from partially crystallized felsic magma and from disaggregated rapakivi granite and granitoid xenoliths whereas in the MMEs the xenocrysts are solely derived from partially crystallized felsic magma. Disaggregation of the mafic magma to form MMEs and equilibration with the host have produced micro-enclaves and recrystallized borders of MMEs. Disaggregation of the mafic magma has also produced needle-like apatite crystals incorporated from the mafic magma into the hybrid magma; acicular apatite is typical in MMEs and pillow-like MMEs and is indicative of rapid crystallization. The mass-fraction of mafic magma (Xm) in the hybrid rock is up to 0.3. The Xm in hybrid MMEs and pillow-like MMEs varies from 0.4 to 0.9. The temperature difference between the two magmas probably caused convection that spread the disaggregated mafic magma throughout the postulated layered magma chamber. The injected mafic magma simultaneously mingled and mixed with the felsic magma which was superheated, assisting the chemical exchange. The interaction of hybrid MME magma with the hybrid magmas was possibly made more effective by diffusion of fluorine from the felsic magma into the mafic magma. The composition of minerals indicates intensive interaction of the mafic magma and the felsic host, with the temperature of equilibrium being in the range of 900° to 750°C. The crystallization of granites of the complex occurred between 850-650°C, with an oxygen fugacity parallel or slightly below the QFM buffer. Besides geochemical evidence, a hybrid origin for the rocks is also shown by the composition of Fe-Mg silicates. Pyroxenes, however, from the hybrid rocks and MMEs show disequilibrium having crystallized at various stages of the hybridization event. Mantling of the alkali feldspar megacrysts by micrographic plagioclase- quartz intergrowth and plagioclase shells has taken place at a temperature of 850° to 750°C at a pressure under 2 kbar. In the main part of the Wiborg batholith, any indication of large-scale hybridization between rapakivi and diabase magmas are lacking. A possible high velocity underplate beneath the batholith may have been a heat source for the partially crystallized rapakivi granite magma to produce corroded partially melted alkali feldspar megacrysts and the rapakivi texture without intensive magma mixing.