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We examine the hypothesis that internal dual-energy X-ray absorptiometry (DXA) structural variables measured at the femoral neck and trochanter cross sections will improve prediction of fractures at these sites in addition to areal BMD (aBMD). We present an analysis of the internal distribution of bone at the site of these fractures using baseline hip DXA measurement of 1151 participants, mean age (SD) 75 (3) years, in the 14.5-year Perth Longitudinal Study of Aging in Women. Structural differences at the femoral neck (FN) and trochanter (TR) cross sections were compared in 69 participants who went on to sustain femoral neck fracture (FNF) and 59 participants who went on to sustain trochanter fracture (TRF), on average 10 years later, to those who did not fracture. The new structural variables, in addition to aBMD and bone width (W), were Sigma (distribution of bone within scanned area) and Delta (distance between center-of-mineral mass and geometric center), which can be assessed by current DXA programs. At baseline, compared with nonfracture cases, FNF cases had a FNaBMD 7% lower, a FNWidth 3% higher and a FNDelta 29% higher, associated with reduced bone in the superior segment. In FNF Cox proportional hazard analysis, age (hazard ratio [HR 1.39]), total hip aBMD (THaBMD; 0.79), and Delta (1.70) were significant. Addition of FN Delta to the base case of THaBMD and age improved the C statistic from 0.62 to 0.69, p = 0.01. At baseline, TRF cases had a 15% lower TRaBMD with minor differences in Sigma (1%) and Width (2%). In TRF Cox analysis, neither addition of Sigma nor Width improved the model that included age and THaBMD as predictors and did not alter the C-statistic of 0.81. In conclusion, adding measurement of FN Delta, an assessment of superior sector bone loss, to hip aBMD and age substantially improved clinical FNF prediction in older women. [ABSTRACT FROM AUTHOR]

Deformation instability is a macroscopic and microscopic phenomenon of non-uniformity and unstable deformation of materials under stress loading conditions, and it is affected by the intrinsic characteristics of materials, the structural geometry of materials, stress state and environmental conditions. Whether deformation instability is positive and constructive or negative and destructive, it objectively affects daily life at all times and the deformation instability based on metal-bearing analysis in engineering design has always been the focus of attention. Currently, the literature on deformation instability in review papers mainly focuses on the theoretical analysis of deformation instability (instability criteria). However, there are a limited number of papers that comprehensively classify and review the subject from the perspectives of material characteristic response, geometric structure response, analysis method and engineering application. Therefore, this paper aims to provide a comprehensive review of the existing literature on metal deformation instability, covering its fundamental principles, analytical methods, and engineering practices. The phenomenon and definition of deformation instability, the principle and viewpoint of deformation instability, the theoretical analysis, experimental research and simulation calculation of deformation instability, and the engineering application and prospect of deformation instability are described. This will provide a reference for metal bearing analysis and deformation instability design according to material deformation instability, structural deformation instability and localization conditions of deformation instability, etc. From the perspective of practical engineering applications, regarding the key problems in researching deformation instability, using reverse thinking to deduce and analyze the characteristics of deformation instability is the main trend of future research. [ABSTRACT FROM AUTHOR]

Deformation instability is a macroscopic and microscopic phenomenon of non-uniformity and unstable deformation of materials under stress loading conditions, and it is affected by the intrinsic characteristics of materials, the structural geometry of materials, stress state and environmental conditions. Whether deformation instability is positive and constructive or negative and destructive, it objectively affects daily life at all times and the deformation instability based on metal-bearing analysis in engineering design has always been the focus of attention. Currently, the literature on deformation instability in review papers mainly focuses on the theoretical analysis of deformation instability (instability criteria). However, there are a limited number of papers that comprehensively classify and review the subject from the perspectives of material characteristic response, geometric structure response, analysis method and engineering application. Therefore, this paper aims to provide a comprehensive review of the existing literature on metal deformation instability, covering its fundamental principles, analytical methods, and engineering practices. The phenomenon and definition of deformation instability, the principle and viewpoint of deformation instability, the theoretical analysis, experimental research and simulation calculation of deformation instability, and the engineering application and prospect of deformation instability are described. This will provide a reference for metal bearing analysis and deformation instability design according to material deformation instability, structural deformation instability and localization conditions of deformation instability, etc. From the perspective of practical engineering applications, regarding the key problems in researching deformation instability, using reverse thinking to deduce and analyze the characteristics of deformation instability is the main trend of future research.

In this paper the geometrical characteristics and construction method of hex-tri reciprocal frame are studied. The naming rules of structural units, members and joints of hex-tri reciprocal frame are proposed. Based on the study of relationships between the structural geometrical parameters, the formulas for the joint coordinates of the structural unit are derived,and the calculating method for normalized direction vectors of the unit members is also developed. The geometry construction method of hex-tri reciprocal frame is established in this paper. By this method the whole structure is formed as an assembly of the units arranged in rings about the structural center. The influences of the diameter, the length and the binding length of the member on the rise of hex-tri reciprocal frame are analyzed by an example. If the rise of hex-tri reciprocal frame needs to be specified in the design, the values of the diameter, the length and the binding length of the structural member need to be coordinated to meet the design requirements.

The strength of tectonic deformation in tectonically complex regions, particularly multi-stage superimposed tectonic regions, can have a significant impact on shale gas preservation conditions. However, differential tectonic deformation has still not been quantitatively constrained, and its impact on the preservation conditions of shale gas is thus poorly understood in the northern Guizhou Province, southwest China. This study investigates the differential preservation conditions of marine shale gas in four eroded synclines (including Shixi, Daozhen, Zhongguan, and Fuyan Synclines) of the northern Guizhou Province. Interpretation of structures in field outcrops, geometry and kinematic analysis, and typical gas reservoir anatomy are combined to quantitatively explore the effect of superimposed deformation on the preservation conditions of shale gas. According to a set of new structural and kinematic constraints, the Riedel shear model for strike-slip faults is firstly conducted in the eroded synclines in the northern Guizhou Province, which innovatively established a linkage between detailed structural analysis and evaluation of shale-gas preservation conditions. We demonstrate that superimposing of deformations plays a role in differential accumulation in eroded synclines. The results indicate that (1) fault strike in the Shixi Syncline is more concentrated than Zhongguan and Fuyan Synclines, whereas fault strikes in the Zhongguan and Fuyan Synclines are more scattered. There is only one direction of maximum principal stress (σ 1) in the Shixi and Daozhen Synclines. There are two maximum principal stress directions (σ 1) in the Zhongguan and Fuyan Synclines. The Zhongguan and the Fuyan Synclines have tensional environments, whereas the Shixi and the Daozhen Syncline have compressional settings; (2) the formation dip angle, distance to a class II fracture, average detachment layer thickness, intensity of superimposed modifications, and interlimb angle may be positively correlated with gas content; (3) the progressive transformation pattern is established. These findings lay the foundation for the future research on the differential preservation mechanism of eroded synclines and may be useful for enhancing research on worldwide strike-slip faults controlling hydrocarbon accumulation. • Riedel shear model first adopted on shale-gas preservation in complex structure zone. • Superimposed deformation was clarified by new structural and kinematic constraints. • Differential shale-gas conceptual accumulation model on eroded synclines is built. • Strike-slip stepwise transformation model for shale-gas accumulation first stressed. [ABSTRACT FROM AUTHOR]

Many important public buildings have suffered significant damages due to terrorist attacks in the last few decades. This paper investigates the behavior of structures with steel plate shear wall lateral load resisting system under various blast loadings. A number of twenty steel frames with different heights and widths subjected to four different blast scenarios are modeled and analyzed in opensees software. The results showed that structures with steel plate shear wall systems subjected to blast loading have better behavior in high-rise structures than in low-rise structures in terms of drift and ductility ratio. The steel plate shear wall system exhibited shear-dominated, flexural-dominated, and shear-flexural behavior in low-rise, high-rise, and mid-rise structures, respectively. Besides, in mid-rise and high-rise structures, the roof's maximum horizontal acceleration occurs in free vibration, whereas in low-rise structures, this amount is experienced during loading. Furthermore, the maximum horizontal displacement of the roof occurs in free vibration, and as the number of stories increases, this amount will occur later. [ABSTRACT FROM AUTHOR]

The gold deposits in the Youjiang basin, totaling ​> ​25 Moz gold, have traditionally been thought to be of Carlin-type, particularly those with extensional structural geometries in the northern basin dominated by platform sedimentary sequences. However, the structural geometries, mineralization styles and alteration types for the Jinya, Gaolong and Nakuang gold deposits in the south-central part of the basin are remarkably similar to those of unequivocal orogenic gold deposits. Structural studies show that gold mineralization in the three gold deposits was controlled by tight "locked-up" anticlines with NW−SE- to E−W-trending and/or concomitant thrusts and/or shear zones, which resulted from NE−SW- to N–S-trending compression or transpression following the Early Triassic closure of the Paleo-Tethyan Ocean. Alteration zones in these deposits are dominated by silicification (quartz), sericitization, sulfidation and carbonation. Zoned pyrites in these deposits comprise Au-poor cores and invisible Au-bearing rims with minor external free gold. Euhedral to subhedral auriferous arsenopyrites also contribute to the gold budget. These features indicate that the three gold deposits are sediment-hosted orogenic gold deposits that contrast markedly with the Carlin-type gold deposits in the northern part of the Youjiang basin in terms of structural geometry and timing, mineralization style and nature of associated alteration. Although additional reliable ages using robust methodologies are still required, the older isotopic ages of the gold deposits in the south-central Youjiang basin are also consistent with earlier formation during transpression that predated extension during orogenic collapse, the period of formation of the Carlin-type gold deposits in the northern Youjiang basin. Image 1 • Gold deposits in south-central Youjiang basin hosted by tight anticlines/thrusts. • Gold deposits in south-central Youjiang basin belong to orogenic gold. • Orogenic gold deposits were related to Triassic intraplate shortening. [ABSTRACT FROM AUTHOR]

Summary: Analyses using newly developed structural measures of minimal model (aBMD, W, Sigma, Delta) in a Chinese female age-matched cohort of femoral neck fracture patients and non-fracture community controls resulted in improved fracture prediction, suggesting the usefulness of new variables, extending the value of widely available DXA technology. Introduction: We have developed a new approach to evaluate 2D femoral neck (FN) structure, the minimal model (MM). This model includes FNaBMD and FNWidth with two new internal structural measures, the standard deviation of normalized mineral mass projection profile distribution (FNSigma) and the displacement between center of mineral (CoM) mass and geometric center of mineral mass projection profile (FNDelta). Methods: Differences in these four structural measurements together with age, weight, and height were compared in the contralateral hip of 285 FN fracture Chinese female patients and 261 age-matched community controls. Structural variables were calculated from DXA equivalent 2D images obtained from QCT scans analyzed using Mindways Software. Results: Review of FN scanned profiles of fracture patients and controls identified substantial reduction in mineral mass in the superior segment of FN. Fracture participants were taller, weighed less, and had lower FNaBMD and larger FNDelta, due to a larger inferior displacement in the CoM, consistent with greater reduction in superior segment bone. Logistic regression identified increased height, reduced FNaBMD, increased FNDelta, and reduced FNSigma per SD as significant independent contributors to differentiating fracture from non-fracture. Area under ROC analysis identified significant improvement in discrimination with the addition of FNDelta and FNSigma to the model including age, height, weight, and FNaBMD (C statistic 0.87 and 0.84 respectively). Conclusions: These data extend previous data that identified the benefit of 2D FN internal structural information in discriminating those at increased future fracture risk from recently fractured individuals. These data support continuing investigation of MM analysis as a straightforward analytical approach adding value to DXA hip aBMD in predicting fracture risk. [ABSTRACT FROM AUTHOR]

The 13-km-long Sanshandao gold belt along the NNE-trending Sanshandao Fault has highly variable orogenic gold endowment along-strike. New thermochronological data from the small Cangshang gold deposit demonstrate similar degrees of uplift and exhumation rates as for larger deposits, negating selective preservation as the prime gold-endowment factor. The Haiyu, Sanshandao, Xiling, and Cangshang deposits, of variable gold endowment, lie adjacent to NE-ENE-trending jogs, similar to those at Jiaojia and Linglong, so these structures cannot be the prime control on gold mineralization. Ore-zones show a broad gentle northeast plunge, with the southwestern Cangshang and Xinli deposits being closest to the ground surface, and the northeastern Haiyu deposit being the deepest. Thus, preferential erosion of the shallower southwestern orebodies could be a factor affecting endowment. Another variable is the depth of drilling. At Haiyu-Sanshandao, gold mineralization is better developed on more gently dipping fault segments, consistent with a thrust component of oblique slip along them. Relative to the northeastern deposits, the Cangshang and Xinli deposits are located in areas where relatively shallow drilling has intersected ore zones on steeply dipping fault segments, indicating the potential for deeper drilling to intersect gold ore along deeper more gently dipping segments. Heterogeneous gold endowment is thus largely a formational factor related to the plunge of orebodies combined with the variable depth of drilling along the Sanshandao Fault. Over the entire Jiaodong gold province, there are equivalent-age mesozonal to epizonal orebodies, implicating their preservation at different crustal levels and thus increasing the province-scale gold endowment potential and probability of further exploration discoveries. [ABSTRACT FROM AUTHOR]

Most, if not all, orogenic gold deposits form during the late stages of deformation. In some cases, there is barren pre-mineralization hydrothermal alteration which may be part of a single progressive hydrothermal event or a temporally distinct event relative to deposition of gold. At the Huangjindong orogenic gold deposit in the Jiangnan Orogen of southern China, there are two phases of vein generation, the earlier of which is largely barren. Structural analysis, petrography, mineralogy, and in situ laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) gold mapping of different generations of gold-bearing sulfides reveal the relationship between different phases of hydrothermal alteration and quartz veins. Pre-existing barren and brittle quartz veins, which are controlled by tight folds and thrust faults, provide favorable competent hosts for later overprinting by gold-bearing ore-bearing fluids that infiltrated during ongoing reverse-sinistral fault movement. These overpressured fluids caused hydrofracturing to complete brecciation of segments of the earlier quartz veins and associated pre-existing breccias, with deposition of auriferous quartz-sulfide veins and breccia cements or matrices within them. Although fluid inclusion data are non-definitive, fluid pressure fluctuations are interpreted to have resulted in phase separation within the ore fluid which was primarily responsible for destabilization of gold complexes and deposition of native gold with other invisible gold-bearing ore-related sulfides formed by sulfidation reactions, in hydrofractures and breccia matrices. Thus, competent barren quartz veins in fold/thrust belts may locally host superimposed gold mineralization and provide favorable targets for gold resources. [ABSTRACT FROM AUTHOR]

Blue-color-emitting organic semiconductors are of significance for organic light-emitting diodes (OLEDs). In this study, through Suzuki coupling polymerization, three 1,4-naphthalene-based copolymers—namely, PNP(1,4)-PT, PNP(1,4)-TF, and PNP(1,4)-ANT—were designed and synthesized. The variation of comonomers, phenothiazine (PT), triphenylamine substituted fluorene (TF), and anthanthrene (ANT), effectively tuned the emitting color and device performance of poly(9-vinyl carbazole) (PVK)-based OLEDs. Especially, the polymer PNP(1,4)-TF, bearing perpendicular aryl side groups, showed a most twisted structural geometry, which enabled an ultra-high thermal stability and a best performance with blue emitting in PVK-host-based OLEDs. Overall, in this work, we demonstrate a promising blue-color-emitting polymer through structural geometry manipulation.

With very few exceptions, orogenic gold deposits formed in subduction-related tectonic settings in accretionary to collisional orogenic belts from Archean to Tertiary times. Their genesis, including metal and fluid source, fluid pathways, depositional mechanisms, and timing relative to regional structural and metamorphic events, continues to be controversial. However, there is now general agreement that these deposits formed from metamorphic fluids, either from metamorphism of intra-basinal rock sequences or de-volatilization of a subducted sediment wedge, during a change from a compressional to transpressional, less commonly transtensional, stress regime, prior to orogenic collapse. In the case of Archean and Paleoproterozoic deposits, the formation of orogenic gold deposits was one of the last events prior to cratonization. The late timing of orogenic gold deposits within the structural evolution of the host orogen implies that any earlier structures may be mineralized and that the current structural geometry of the gold deposits is equivalent to that at the time of their formation provided that there has been no significant post-gold orogenic overprint. Within the host volcano-sedimentary sequences at the province scale, world-class orogenic gold deposits are most commonly located in second-order structures adjacent to crustal scale faults and shear zones, representing the first-order ore-forming fluid pathways, and whose deep lithospheric connection is marked by lamprophyre intrusions which, however, have no direct genetic association with gold deposition. More specifically, the gold deposits are located adjacent to ∼10°–25° district-scale jogs in these crustal-scale faults. These jogs are commonly the site of arrays of ∼70° cross faults that accommodate the bending of the more rigid components, for example volcanic rocks and intrusive sills, of the host belts. Rotation of blocks between these accommodation faults causes failure of more competent units and/or reactivation and dilation of pre-existing structures, leading to deposit-scale focussing of ore-fluid and gold deposition. Anticlinal or antiformal fold hinges, particularly those of ‘locked-up’ folds with ∼30° apical angles and overturned back limbs, represent sites of brittle-ductile rock failure and provide one of the more robust parameters for location of orogenic gold deposits. In orogenic belts with abundant pre-gold granitic intrusions, particularly Precambrian granite-greenstone terranes, the boundaries between the rigid granitic bodies and more ductile greenstone sequences are commonly sites of heterogeneous stress and inhomogeneous strain. Thus, contacts between granitic intrusions and volcano-sedimentary sequences are common sites of ore-fluid infiltration and gold deposition. For orogenic gold deposits at deeper crustal levels, ore-forming fluids are commonly focused along strain gradients between more compressional zones where volcano-sedimentary sequences are thinned and relatively more extensional zones where they are thickened. World-class orogenic gold deposits are commonly located in the deformed volcano-sedimentary sequences in such strain gradients adjacent to triple-point junctions defined by the granitic intrusions, or along the zones of assembly of micro-blocks on a regional scale. These repetitive province to district-scale geometrical patterns of structures within the orogenic belts are clearly critical parameters in geology-based exploration targeting for orogenic gold deposits. [ABSTRACT FROM AUTHOR]

Surveying a monumental building damaged by the earthquake means to analyse its geometries, the structural elements, the connection still exist between the different parts, in order to define its state of conservation, to make structural analysis and to plan a proper project of restoration, consolidation, seismic improvement or addition of new elements. The survey of structural geometry represents the first necessary moment of building' knowledge investigation, to be performed after the securing of the building by the Firefighters or Civil Protection. How and by which instruments the geometric analysis are conducted depends on many factors, not always exclusively on the will of the experts involved in the restoration project, but more often dictated by political, technical, social or economic needs. The accurate geometrical survey is referred as fundamental operation even by national Directive for evaluation and earthquake risk reduction of cultural heritage (GU n. 24 - 29/01/2008 and 2011 updates), which defines guidelines for preventive interventions on built heritage in order to make the structures less vulnerable in case of earthquake. Nowadays, the wide use of tools and accurate surveying techniques makes it possible to achieve an adequate level of accuracy of information related to the buildings, overcoming the difficulties due to accessibility of the damaged structures. The geometrical survey of the Basilica of Santa Maria di Collemaggio in L'Aquila, was made by Politecnico di Milano starting from 2013, within the project "Ripartire da Collemaggio" (http:/www.ungiornoacollemaggio.it/content/2027), financed by Eniservizi. The basilica, an important symbol for the community of L'Aquila, was gravely damaged by the earthquake of 6th April 2009. The objective of Eni was to turn the restoration of the building in a re-birth moment for all the community. The knowledge step was aimed to plan a restoration project able of returning the basilica to a safe and full use. In the two years knowledge investigation steps (geometric survey, historical and stratigraphic analysis, materials investigation, structures and soils examination, in situ tests and numerical elaborations) was involved an interdisciplinary group of researchers from various Italian universities, Politecnico di Milano, Università La Sapienza in Rome and the University of L'Aquila, called to provide a scientific advice to the Soprintendenza ai Beni Architettonici e Paesaggistici per l'Abruzzo, project manager of the restoration step. In early 2016 the yard of restoration was opened and it is still on-going. The geometrical survey of the basilica was aim to investigate, measure and represent the exact geometry of the damaged structures and their three-dimensional complexity; the survey was planned choosing the tools and methods most appropriate in relation with the accessibility and safety of the structures, the operating ranges of acquisition and the level of detail required by the analysis and the project. This meant to integrate global and local surveying techniques, in order to cross relate data derived by different tools and to make the graphical restitution of the entire monumental complex: topography, laser scanning, photogrammetry, but also hands on instruments, at a scale of representation from 1:1 to 1:50. The laser scanner survey, registered in the accurate geomatics network, responded to the need to punctually investigate and interpret the geometrical configuration of different spaces of the Basilica, as well as its structural articulation, enabling a series of horizontal and vertical profiles, as requested by various experts involved in the diagnostic steps. HBIM model (Historical Building Information Modeling) of the entire basilica was primarily intended as a tool for stereotomic description of the building and its parts, following the constructive logic of each structural element; then it was used as a support tool for the restoration simulation, project, management and yard. To perform the division of the building in its constructive elements, sometimes it has been used stratigraphic methodologies and instruments of analysis. The entirety of the geometric and structural complexity of the basilica, was guarantee using sophisticated 3D software and drawing complex entities, integrated and stored in the parametric BIM logic. This process has allowed to accurately and timely represent the geometry of the structural elements, of the areas characterized by crushing, empties, variations of the masonry sections and out of plumbs. It is on the pillars of the nave that was focused the attention of survey: the will to preserve as much as possible the existing structures, in their material authenticity, required a careful analysis of each individual stone element of each pillar, investigated in its geometry, texture and state of conservation. The aim of the project was to ward a complete replacement of the pillars, preferring instead a removing and replacing intervention of only of the stone ashlars completely deteriorated and no longer recoverable, considering the question of structural safety as fundamental. The HBIM of the basilica had the primary function of connecting into one virtual space all the available data; that model has also been made as a tool for managing the restoration yard, supporting the computation of stone to buy, quarry and grossly slot, saving time on site. Different and complementary skills were used in every knowledge and restoration steps; the accurate analysis of the structures made it possible to plan a consolidation and restoration project as close as possible to the structural conception of the existing building, adding only the new structural elements necessary to increase the resistance and to guarantee the safety of the structures, also in case of new earthquake. The Italian Codice dei Beni culturali e del paesaggio (DL n.42/2004), at paragraph 4 of art. 29, states that the restoration includes structural improvements. For the restoration of Collemaggio the solutions chosen were the ones able to be more effective and, at the same time, less invasive, more respectful as possible of the sacredness of the architecture, its highest historical significance, the authenticity of the material and its cultural significance. The main principles and criteria of restoration were: maximum correspondence of conservation doctrine, with a focus on improving the structural characteristics compared to the seismic risk; exemplarity of the management practices of the restoration process; exemplarity of innovative techniques; transparency of all processes and accurate communication of cultural and scientific content. Despite of some inevitable compromises, the detailed knowledge of the building allowed to design punctual interventions, inserting new structures where the oldest were collapsed and consolidating damaged elements, in order to improve the global safety of the building but without modifying substantially the structural conception of the stratified basilica. [ABSTRACT FROM AUTHOR]

Due to unique reversible martensitic transformation, superelastic NiTi can be strained to several percents and fully recover upon unloading. It is well accepted that superelastic NiTi under primarily tensile deformation is localized rather than homogenous. In this paper, we examine the heterogeneous deformation of superelastic NiTi sheets with various aspect ratios (the ratio of gauge width to gauge length). For the specimens with aspect ratios lower than 2, the deformation at quasi-static loading condition is realized by the nucleation and propagation of a major transformation band. For the specimen with aspect ratio of 4, multiple transformation bands coexist at the loading rate as low as 1 × 10−4/s, and the geometry of the transformation band is no longer well-defined. Finite element analysis indicates that the transition of localized deformation mode is attributable to the enhanced stress biaxiality and stress heterogeneity with the increasing aspect ratio. [ABSTRACT FROM AUTHOR]

The Yao Shan complex, a massif near the southern segment of the Ailao Shan–Red River (ASRR) shear zone, bears important information on the structural framework of the massif and the kinematics of ductile shearing along the ASRR shear zone. In this contribution, structural, microstructural, quartz c-axis fabric, magnetic fabric, and geochronologic data are used to determine the structural framework of the Yao Shan massif and its tectonic implications for the ASRR shear zone. The Yao Shan complex is characterized by an overall linear A-type antiform that contains a core of high-grade metamorphic rocks with Palaeoproterozoic to Mesozoic protoliths and a mantle of Permo-Triassic low-grade rocks. Both the high-grade metamorphic core and low-grade Permo-Triassic rocks have experienced progressive ductile shearing. Anisotropy of magnetic susceptibility (AMS) results from 17 samples collected along the Xinjie–Pingbian section across the complex show that magnetic lineation (Kmax) and foliation (Kmax–Kint) are generally subparallel to the corresponding structural elements in the sheared rocks. The shape parameter E values of the magnetic ellipsoids are indicative of dominantly oblate and plane strain, but vary with protolith type and degree of strain among the various rock types. In agreement with the field and microstructural observations, the corrected degree of anisotropy (Pj) values reflect high shear strain in the core rocks and relatively low shear strain in the low-grade strata. A kinematic analysis based on structural and magnetic fabric data shows that both left- and right-lateral shear occurred during the deformation of the Yao Shan complex. Therefore, instead of being an element of the ASRR shear zone, the Yao Shan complex constitutes a crustal-scale inharmonic A-type fold with a fold axis parallel to the stretching lineation. Geochronologic data reveal that the folding occurred coevally with ductile shearing of the middle to lower crust between ca. 30 and 21 Ma. [ABSTRACT FROM PUBLISHER]

Summary: Many attempts have been made to improve the predictive ability of areal bone mineral density (aBMD) which integrates bone mass and area. The addition of an extra variable derived from the hip dual-energy X-ray (DXA) image TR_σ, which describes distribution of mass within the scanned area of the trochanter, improved prediction of 15-year hip fracture probability in elderly women. Introduction: Two-dimensional DXA imaging of the proximal femur to produce an aBMD is a clinically useful predictor of future fracture risk. Further analysis of the DXA image to produce an eight-variable hip structure analysis (Beck HSA) has been developed to improve understanding of structural factors determining hip bone strength at each of three proximal femur sites, the narrow femoral neck (NN), intertrochanter (TR) and shaft (S). Recently, data on four measurements derived from the currently used eight Beck HSA variables were used to capture population variation in bone structure at each site. These include two previously used variables, the localised aBMD and the sub-periosteal width (W) applying to 5-mm sections (at each sites), and two new variables, standard deviation of normalised mineral-mass projection profile distribution (σ), and displacement between centre-of-mineral mass and geometric centre-of-mineral mass of projection profile (δ). Methods: Using a cohort of 1159 women, mean baseline age 75, who sustained 139 hip fractures over 15 years, we determined whether these measures significantly improved 15-year hip fracture prediction compared to current approach utilising age and total hip aBMD. To describe the most parsimonious model for hip fracture risk prediction, the 12 base measures (4 from each site), total hip aBMD and age were evaluated in stepwise logistic regression models. Results: The final model included TR_σ, total hip aBMD and age and provided improved utility for hip fracture prediction compared to total hip aBMD and age alone (C-statistic 0.73 vs. 0.69, P = 0.009 and net reclassification improvement 0.164, P < 0.001, respectively). Conclusions: Addition of TR_σ to total hip aBMD and age substantially improved prediction of 15-year hip fracture risk in this cohort of elderly women. [ABSTRACT FROM AUTHOR]