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The biological adaptation of the human lineage to its environment is a recurring question in paleoanthropology. Particularly, how eco‐geographic factors (e.g., environmental temperature and humidity) have shaped upper airway morphology in hominins have been subject to continuing debate. Nasal shape is the result of many intertwined factors that include, but are not limited to, genetic drift, sexual selection, or adaptation to climate. A quantification of nasal airway (NA) morphological variation in modern human populations is crucial to better understand these multiple factors. In the present research, we study 195 in vivo CT scans of adult individuals collected in five different geographic areas (Chile, France, Cambodia, Russia, and South Africa). After segmentation of the nasal airway, we reconstruct 3D meshes that are analyzed with a landmark‐free geometric morphometrics method based on surface deformation. Our results highlight subtle but statistically significant morphological differences between our five samples. The two morphologically closest groups are France and Russia, whose NAs are longer and narrower, with an important protrusion of the supero‐anterior part. The Cambodian sample is the most morphologically distinct and clustered sample, with a mean NA that is wider and shorter. On the contrary, the Chilean sample form the most scattered cluster with the greatest intra‐population variation. The South African sample is morphologically close to the Cambodian sample, but also partially overlaps the French and Russian variation. Interestingly, we record no correlation between NA volume and geographic groups, which raises the question of climate‐related metabolic demands for oxygen consumption. The other factors of variation (sex and age) have no influence on the NA shape in our samples. However, NA volume varies significantly according both to sex and age: it is higher in males than in females and tends to increase with age. In contrast, we observe no effect of temperature or humidity on NA volume. Finally, we highlight the important influence of asymmetries related to nasal septum deviations in NA shape variation. [ABSTRACT FROM AUTHOR]

Despite the profound roles of surface deformation monitoring techniques in observing permafrost surface stability, predetermining the approximate location and time of possibly occurring severe permafrost degradation before applying these techniques is extremely necessary, but has received little attention. Taking the oil tank collapse accident in the Norilsk region as a case, we explored this concern by analyzing the permafrost deformation mechanisms and determining early surface deformation signals. Regarding this case, we firstly applied the Small Baseline Subset Interferometric Synthetic Aperture Radar (SBAS-InSAR) technique to obtain its permafrost surface deformation rate, then utilized a sine model to decompose its interannual deformation and seasonal deformation, and finally compared the relationship between the topographic slope and deformation rate. Based on experimental results, we reveal that when the annual average temperature continuously increases at a rate of 2 ° C/year for 2∼3 consecutive years, permafrost areas with relatively large topographic slopes (>15 ° ) are more prone to severe surface deformation during the summer thaw period. Therefore, this paper suggests that permafrost areas with large topographic slopes (>15 ° ) should be taken as the key surveillance areas, and that the appropriate monitoring time for employing surface deformation monitoring techniques should be the summer thawing period after a continuous increase in annual average temperature at a rate of 2 ° C/year for 2∼3 years. [ABSTRACT FROM AUTHOR]

In-situ monitoring system is absolutely necessary for a long-distance linear pipeline infrastructure in permafrost regions due to the complicated interaction between buried pipeline and its harsh permafrost environment. To study this complex problem, a comprehensive in-situ monitoring system has been designed and established along the China–Russia Crude Oil Pipeline (CRCOP), which is one of vital energy channels for importing crude oil from Russia to China. This monitoring system can record the meteorological data, ground temperature and water content within the permafrost foundation, vertical settlement of the oil pipe, ground surface deformation on the pipeline right-of-way (on-ROW), as well as the thaw bulb around the pipeline at four sites with different engineering geological conditions. In this paper, the layout and instrumentation of the whole monitoring system and monitoring methods are described in detail, and then the thermal regime of permafrost on-ROW and off-ROW and cooling performance of the mitigative measures on foundation soils are evaluated. Results show that heat dissipated from the CRCOP lead to the rapid degradation of permafrost on-ROW and produce different sizes of thaw bulb around the oil pipelines. The mitigative measures, including insulation layer, two-phase closed thermosyphon and U-shaped air-ventilated pipes, are effective to minimize permafrost degradation and ensure the thermal stability of permafrost foundation along the CRCOP. Some recommendations are proposed for future research and for the monitoring system to be improved. This monitoring system can provide multi-field data to clarify the interaction between pipeline and permafrost degradation under different geological conditions, and guide the design and maintenance of the buried warm pipeline in permafrost regions. • An in-situ monitoring system is set up along the CRCOP in permafrost regions. • The geological characteristics and layout of instrumentation at four monitoring sites are reported. • The integrated monitoring method for pipeline-permafrost interaction are presented. • Thermal effect of buried warm oil pipe on underlying permafrost is observed. • Cooling performance of the insulation layer, thermosyphon and U-shaped air-ventilated pipes is evaluated. [ABSTRACT FROM AUTHOR]

The results are presented of the first studies to be carried out on 4He retention under mechanical deformation of isoferroplatinum (Pt3Fe) from a unique placer deposit at the Konder and Uorgalan rivers and from indigenous shows of the alkaline-ultrabasic Konder Massif (Khabarovsk krai, Russia). It was found that the deformation of Pt3Fe of the Pm-3m cell resulted in structural transformations with the appearance of domains and subsequent conversion into native platinum (Pt, Fe) of the Fm-3m cell. [ABSTRACT FROM AUTHOR]

Methods of determining the total deformation modulus of frozen ground are analyzed. Published data and the results of more than 800 compression tests, conducted by the authors in the course of engineering research in different regions of the cryolithozone of Russia, are colligated. It is shown that GOST 25100-2011 and SP 25.13330.2012 specifications are inconsistent and there is no justification for subdividing frozen fine-disperse soils into plasto- and solid-frozen. Soils are given for including in the revised SP 'Foundation beds and foundations on permafrost' the requirement that foundation beds on frozen fine-disperse soils be reckoned in terms of both groups of limiting states - deformations and carrying capacity. Suggestions are given for determining the deformation modulus by means of compression tests. [ABSTRACT FROM AUTHOR]

We investigated the surface deformations of one of the strongest earthquakes in the Baikal rift zone occurred on April 04, 1950. This event gave an impulse to the development of seismological and seismotectonic researches in southern East Siberia though the event remained poorly studied. We established that the source of the M = 6.9 Mondy earthquake manifested on the surface as a rupture zone 5.4 km long and at least 0.6-1.7 km wide. The rupture zone comprises northern and southern segments trending WNW-ESE (nearly E-W) and NW-SE, respectively. The structural and geological observations testify to left-lateral slip along nearly E-W trending ruptures that is consistent with the recent solution of focal mechanism and previous geomorphologic observations. The open question concerns the vertical component of displacement as the direct records in the excavations show both normal and reverse offsets. The Mondy earthquake initiated the active development of thermokarst, which is expressed on the surface by subsidences and sinkholes spatially associated with the seismogenic ruptures. The melting of sporadic permafrost in the fracture zones and temporary streams contribute to a good state of preservation of the surface ruptures. Numerous neptunian dikes are revealed on the GPR profiles. Their formation is associated with both filling the blind seismogenic fractures and fall of sediments in the sinkholes. Some drawdowns associated with a subsidence as a result of ejected liquefied sand. Outside of the 1950 earthquake, at least two other rupturing palaeoevents occurred in the study area after 4628-5212 BP and 2968-3241 BP. The obtained results provided a basis for further investigations in the epicentral area of the 1950 earthquake in order to study the dynamics of the postseismic exogenous processes, search new surface ruptures east of the village of Mondy and constrain the recurrence interval of earthquakes along the Mondy fault. [ABSTRACT FROM AUTHOR]

Abstract: We present the results of tectonophysical reconstruction of natural stresses of the Earth''s crust in the Altai–Sayan mountain region using cataclastic analysis of fault slips and seismic data on the focal mechanisms of earthquakes. This method allows one to obtain the parameters of the total stress tensor by invoking additional data: generalized experimental data on the brittle fracture of rocks, seismic data on the released stress of strong earthquakes, and data on the topography and density of rocks. Results of the tectonophysical reconstruction of stresses showed significant inhomogeneity of the stress state, which is manifested not only in the variation of the strike and dip of the principal axes of the stress tensor, determining changes in the geodynamic regime of the Earth''s crust, but also in the close location of the regions of high and low isotropic tectonic pressure in relation to the lithostatic pressure. The variance of the ratio of tectonic pressure to lithostatic pressure is in the range of 0.59–1.31, with an average value for the region close to unity. This paper discusses internal or external mechanisms capable of generating the stress field obtained by the tectonophysical reconstruction. [Copyright &y& Elsevier]

The complex analysis of parameters characterizing the modern deformations of the Earth's crust and upper mantle in the territory of the Mongolia-Siberian Area is made. Directions of principal tension axes of stress-tensors, calculated with the use of earthquake source mechanisms have been taken as parameters of modern deformations at the level of the middle crust; directions of axes of horizontal strains in the geodesic network by the GPS data have been taken as such parameters at the level of the Earth's surface. The strain parameters for the mantle depths are the data on seismic anisotropy derived from the published sources about the results of studies on splitting of transversal waves from distant earthquakes. Seismic anisotropy is interpreted as the ordered orientation of olivine crystals, which appears with great strains resulting from the flow of the mantle material. It has been shown that directions of extensional strain axes (minimal compression) by geodesic and seismological data coincide with anisotropy directions in the upper mantle in the region whose median value is 310°-320°. The observed mechanical coupling of the crust and the upper mantle of the Mongolia-Siberian Mobile Area shows the participation of the lithospheric mantle in the formation of neotectonical structures and enables us to distinguish the principal processes determining the Late Cenozoic tectogenesis in this territory. One of the leading mechanisms for the neotectonical and modern deformations of the Mongolia-Siberian Region is the large-scale NW-SE material flow in the upper mantle causing both motion of the entire northern part of the continent and divergence of the Eurasia and the Amurian Plate. Lithospheric deformations in the western part of the region are related to collision-induced compression, while those in the central part are caused by interaction of these large-scale tectonic processes. [ABSTRACT FROM AUTHOR]

The article offers information concerning research and development in high-technology sectors of metallurgy industry at the Department of Metallurgy and Strength Physics at the Moscow Institute of Steel and Alloys in Moscow, Russia. Discussing solutions to important problems in the physics of deformation and fracture, it informs that new methods have been developed on the basis of the stochastic mesomechanics of deformation and fracture.

The article reports on the study that explores the deformation of the Northwestern Okhotsk plate in Russia. It suggests that the Eurasia (EU)-North America (NA) plate boundary zone across Northeast Asia still presents open questions within the plate tectonic paradigm. It indicates that the analysis of the fault geometry suggests a central block which is extruding faster bordered east and west by progressively slower extruding blocks until the OK plate boundary faults are encountered.

The article reports on the study that summarizes the field observations and structural data on the relative timing of deformational events in the Bilibino region of the Russian Arctic. It presents new geochronologic and thermochronologic data that help place more reliable age brackets on both deformation and magmatism across the region. It indicates that deformation began in the Late Jurassic, based on fossil ages of synorogenic clastic strata.

The design and foundation bed of the Rostral Columns are ascertained, the soils in their beds are analyzed, the settlement of the columns is calculated, the basic causes of column tilt are indicated, and future work on the beds and foundations is assessed. [ABSTRACT FROM AUTHOR]

Numerical modeling of fault zone evolution and related seismicity can provide an insight into the process of large earthquake occurrences in a complicated fault system. In this paper, we develop a three-dimensional finite-difference numerical model of stress-strain evolution in and around the Chuya and Kurai depressions of Gorny Altai, Russia, to understand the fault zone evolution and the observed distribution of earthquakes in the region. Unlike in previous studies, the process of seismo-tectonic deformations of this region is addressed in a three-dimensional formulation with an improved model of rock massif behavior. A new geometrical model is designed, which is based on the seismotectonic, paleoseismological studies, and high-resolution Space-Radar-Topography-Mission data. The mathematical model applied here represents a set of partial differential equations, which are based on the fundamental conservation laws and constitutive equations for elastic and inelastic deformations. The initial stress state of the model is due to the action of gravity forces. The model is activated by assigning different displacement fields at the model boundaries – strike-slip and GPS-based displacements. The modeling results illustrate the stages of fault zone development and are in satisfactory agreement with the field observations in the case of GPS-based boundary conditions, which has not been modeled yet. Modeled seismic process is associated with the development of a fault zone resulting from the loss of strength in the subsurface points where the inelastic strain exceeds a certain threshold. The areas of high-degree of inelastic strain localization and the modeled fault zone represent an en-echelon system of dextral strike slips and various types of shear bands. The modeled seismic process obeys the Gutenberg-Richter (frequency-magnitude) law. The number of earthquakes in the attenuation part of the rock massif fracture process follows the Omori (aftershock decay) law. • Finite-difference analysis of faulting and seismicity is performed. • New structural model of the Chuya-Kurai region is constructed. • Link is found between the inelastic deformation, fracture and seismicity of rock massif. • GPS-based boundary conditions are applied to the model and verified. • The model reproduces satisfactorily the field observations. [ABSTRACT FROM AUTHOR]