Magma sources involved in the 2002 Nyiragongo eruption, as inferred from an InSAR analysis

International audienceOn 17 January 2002, Nyiragongo volcano erupted along a 20 km-long fracture network extending from the volcano to the city of Goma. The event was captured by InSAR data from the ERS-2 and RADARSAT-1 satellites. A combination of 3D numerical modeling and inversions is used to analyze these displacements. Using Akaike Information Criteria, we determine that a model with two subvertical dikes is the most likely explanation for the 2002 InSAR deformation signal. A first, shallow dike, 2 km high, is associated with the eruptive fissure, and a second, deeper dike, 6 km high and 40 km long, lies about 3 km below the city of Goma. As the deep dike extends laterally for 20 km beneath the gas-rich Lake Kivu, the interaction of magma and dissolved gas should be considered as a significant hazard for future eruptions. A likely scenario for the eruption is that the magma supply to a deep reservoir started ten months before the eruption, as indicated by LP events and tremor. Stress analysis indicates that the deep dike could have triggered the injection of magma from the lake and shallow reservoir into the eruptive dike. The deep dike induced the opening of the southern part of this shallow dike, to which it transmitted magma though a narrow dike. This model is consistent with the geochemical analysis, the lava rheology and the pre- and post-eruptive seismicity. We infer low overpressures (1-10 MPa) for the dikes. These values are consistent with lithostatic crustal stresses close to the dikes and low magma pressure. As a consequence, the dike direction is probably not controlled by stresses but rather by a reduced tensile strength, inherited from previous rift intrusions. The lithostatic stresses indicate that magmatic activity is intense enough to relax tensional stresses associated with the rift extension

Effect of thiosulphate as electron acceptor on glucose and xylose oxidation by Thermoanaerobacter finnii and Thermoanaerobacter sp. isolated from oil field water

#Thermoanaerobacter finnii fermente le glucose et le xylose en lactate, acétate, H2, CO2 et éthanol qui est le produit majeur du métabolisme. Une autre bactérie du genre #Thermoanaerobacter isolée d'une eau de gisement pétrolier produit des quantités aussi importantes d'éthanol que de lactate à partir de ces sucres. L'oxydation du glucose et du xylose par ces deux micro-organismes est complètement modifiée en présence de thiosulfate puisque, dans ces conditions, l'acétate devient le produit majeur du métabolisme des sucres. Cette modification du métabolisme amène à de meilleurs rendements cellulaires et à un meilleur taux de croissance bactérienne lorsque le thiosulfate est utilisé comme accepteur d'électrons. Une plus grande production d'acétate en présence de thiosulfate indique que les bactéries testées récupèrent plus d'énergie des phosphorylations liées au substrat. Ces modifications observées sur le métabolisme des sucres en présence de thiosulfate nous amènent à tenir compte plus précisément du rôle que peut jouer cet accepteur d'électrons dans l'oxydation de la matière organique dans les sources chaudes riches en sulfate sulfuré ou les eaux de gisements pétroliers. (Résumé d'auteur

Sheared sheet intrusions as mechanism for lateral flank displacement on basaltic volcanoes: Applications to Réunion Island volcanoes

International audienceField work carried out on the Piton des Neiges volcano (Réunion Island) suggests that the injection of magma along detachments could trigger flank failure by conjugate opening and shear displacement. We use 3-D numerical models to compare the ability of purely opened sheet intrusions, sheared sheet intrusions, and normal faults to induce flank displacement on basaltic volcanoes. We assume that shear stress change on fractures results from stress anisotropy of the host rock under gravity. Exploring a large range of stress anisotropies, fracture dips, and fracture depth over length ratios, we determine that the amount of shear displacement is independent of the proximity to the ground surface. Sheared sheet intrusions are the most efficient slip medium on volcanoes. Consequently, the largest flank displacement is induced by the longest, deepest sheared intrusion dipping closest to 45° in a host rock with the highest stress anisotropy. Using our model in a forward way, we provide shear and normal displacements for buried fractures. Applying the model to a pile of sills at the Piton des Neiges volcano, we determine that the mean shear displacement caused by each intrusion was 3.7 m, leading to a total of a 180–260 m of lateral displacement for the 50 m high pile of sills. Using our model in an inverse way, we formulate a decision tree to determine some fracture characteristics and the host rock stress anisotropy from ratios of maximum surface displacements. This procedure provides a priori models, which can be used to bound the parameter space before it is explored through a formal inversion. Applying the decision tree to the 1.4 m coeruptive flank displacement recorded at Piton de la Fournaise in 2007, we find that it probably originated from a shallow eastward dipping subhorizontal normal fault

Трупоспалення чернелів-руського черняхівського могильника

Розглянуто матеріали комплексів із кремаціями чернелів-руського могильника черняхівської культури.В статье рассмотрены материалы комплексов с кремациями чернелив-русского могильника черняховской культуры (Западное Подолье), который относится к категории могильников с доминированием ингумаций, что выделяет его среди биритуальных могильников черняховской культуры. Из 288 исследованных погребений черняховской культуры — только две кремации (погребения 44 и 240), что составляет менее 1 % погребений могильника. Кроме того, в могильнике выявлены ритуально нарушенные ингумации, в заполнении могильных ям которых зафиксированы остатки кремаций, что, возможно, связано с сожжением эксгумированных частей этих ингумаций.The article views the materials from the assemblages with cremations in the burial ground Cherneliv-Rus of Chernyakhivska culture (Western Podillya). Cherneliv-Rus burial ground belongs to the category of burial grounds with inhumation prevailed and stands out against the biritual burial grounds of Chernyakhivska culture. There are only two cremations among 288 excavated burials of Chernyakhivska culture (burials 44 and 240). It comprises less than 1% of burials on the burial ground. The latter includes also ritually disturbed inhumations with the remains of cremations in the fi ll of burial pits, which could be related with the burning of exhumated parts of these inhumations

Економічні засади покращення інвестиційного клімату України

Розглянуто тенденцію основних прямих та непрямих інвестицій в країну за певний період та виявлено основну низку системних вад економіко - правового середовища, які заважають припливу іноземних інвестицій. Представлені можливі шляхи покращення інвестиційного клімату України.Considered the main trend of direct and indirect investment in the country for a certain period and found a number of major systemic defects economic and legal environment that hinder foreign investment. Courtesy of the main factors that affect the volume of investment, presents possible ways of improving the investment climate in Ukraine

Український тижневик «Наше слово» (Варшава) як оригінальне джерело вивчення передумов і перебігу примусового переселення українців Польщі в 1944-1947 рр.

Висвітлені передумови й перебіг примусового переселення українців Польщі в 1944-1947 рр. через призму інтерпретації популярного поміж української національної меншини в Польщі тижневика «Наше слово» («НС») й оригінального джерела, що має пізнавальну та академічну цінність. Розділена історична пам’ять українців і поляків на зазначені події посилює інтерес до української періодичної преси в Польщі.Освещены предпосылки и ход принудительного переселения украинцев Польши в 1944-1947 гг. через призму интерпретации популярного среди украинского национального меньшинства в Польше еженедельника «Наше слово» («НС») и оригинального источника, имеющего познавательную и академическую ценность. Разделенная историческая память украинцев и поляков на данное событие усиливает интерес к украинской периодической прессе в Польше.Highlights the prerequisites and course forced Ukrainian migration in Poland 1944-1947 through the prism of popular interpretation among the Ukrainian national minority in the Polish weekly «Our word» («OW») and the original source, which has cognitive and academic value. Split the historical memory of Ukrainian and Polish this event enhances interest in the Ukrainian press in Poland

Genome Analysis of the Anaerobic Thermohalophilic Bacterium Halothermothrix orenii

Halothermothirx orenii is a strictly anaerobic thermohalophilic bacterium isolated from sediment of a Tunisian salt lake. It belongs to the order Halanaerobiales in the phylum Firmicutes. The complete sequence revealed that the genome consists of one circular chromosome of 2578146 bps encoding 2451 predicted genes. This is the first genome sequence of an organism belonging to the Haloanaerobiales. Features of both Gram positive and Gram negative bacteria were identified with the presence of both a sporulating mechanism typical of Firmicutes and a characteristic Gram negative lipopolysaccharide being the most prominent. Protein sequence analyses and metabolic reconstruction reveal a unique combination of strategies for thermophilic and halophilic adaptation. H. orenii can serve as a model organism for the study of the evolution of the Gram negative phenotype as well as the adaptation under thermohalophilic conditions and the development of biotechnological applications under conditions that require high temperatures and high salt concentrations

Isolation and characterization of a new CO-utilizing strain, Thermoanaerobacter thermohydrosulfuricus subsp. carboxydovorans, isolated from a geothermal spring in Turkey

A novel anaerobic, thermophilic, Gram-positive, spore-forming, and sugar-fermenting bacterium (strain TLO) was isolated from a geothermal spring in Ayaş, Turkey. The cells were straight to curved rods, 0.4–0.6 μm in diameter and 3.5–10 μm in length. Spores were terminal and round. The temperature range for growth was 40–80°C, with an optimum at 70°C. The pH optimum was between 6.3 and 6.8. Strain TLO has the capability to ferment a wide variety of mono-, di-, and polysaccharides and proteinaceous substrates, producing mainly lactate, next to acetate, ethanol, alanine, H2, and CO2. Remarkably, the bacterium was able to grow in an atmosphere of up to 25% of CO as sole electron donor. CO oxidation was coupled to H2 and CO2 formation. The G + C content of the genomic DNA was 35.1 mol%. Based on 16S rRNA gene sequence analysis and the DNA–DNA hybridization data, this bacterium is most closely related to Thermoanaerobacter thermohydrosulfuricus and Thermoanaerobacter siderophilus (99% similarity for both). However, strain TLO differs from Thermoanaerobacter thermohydrosulfuricus in important aspects, such as CO-utilization and lipid composition. These differences led us to propose that strain TLO represents a subspecies of Thermoanaerobacter thermohydrosulfuricus, and we therefore name it Thermoanaerobacter thermohydrosulfuricus subsp. carboxydovorans

History of the International Organization for Biological Control Global Working Group on Mass Rearing and Quality Assurance

The International Organization for Biological Control Global Working Group on Mass Rearing and Quality Assurance (MRQA) was established in 1980 as the Working Group on Quality Control (WGQC) to assure success of insect mass rearing for pest management that was being developed in the 1950s and 1960s. Due mostly to the efforts of WGQC, quality control became institutionalized in several insect mass rearing facilities during the 1980s. After addressing autocidal control programs, the WGQC concentrated on entomophagous insects, especially testing the quality of commercial biological control products. Universal Implementation of Quality Control for Mass-Reared Arthropods was finally achieved in the 1990s, having encompassed all aspects from insect production to field application and evaluation. This increased scope prompted a name change from WGQC to Arthropod Mass Rearing and Quality Control (AMRQC). Subsequently, the scope of the Working Group was expanded again and it was renamed MRQA to include a range of applications for mass-reared beneficial invertebrates. The geographic range of MRQA recently was extended beyond North and South America and Europe to include India. This expansion continued as insects for food and feed, networking and instruction, and legal and ethical issues were added to the most recent workshop held in Mexico. Thus, the MRQA continues to evolve as additional invertebrate organisms are mass produced for both established and novel applications